/* C++ Parser. Copyright (C) 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc. Written by Mark Mitchell . This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GCC; see the file COPYING. If not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "config.h" #include "system.h" #include "coretypes.h" #include "tm.h" #include "dyn-string.h" #include "varray.h" #include "cpplib.h" #include "tree.h" #include "cp-tree.h" #include "c-pragma.h" #include "decl.h" #include "flags.h" #include "diagnostic.h" #include "toplev.h" #include "output.h" /* The lexer. */ /* Overview -------- A cp_lexer represents a stream of cp_tokens. It allows arbitrary look-ahead. Methodology ----------- We use a circular buffer to store incoming tokens. Some artifacts of the C++ language (such as the expression/declaration ambiguity) require arbitrary look-ahead. The strategy we adopt for dealing with these problems is to attempt to parse one construct (e.g., the declaration) and fall back to the other (e.g., the expression) if that attempt does not succeed. Therefore, we must sometimes store an arbitrary number of tokens. The parser routinely peeks at the next token, and then consumes it later. That also requires a buffer in which to store the tokens. In order to easily permit adding tokens to the end of the buffer, while removing them from the beginning of the buffer, we use a circular buffer. */ /* A C++ token. */ typedef struct cp_token GTY (()) { /* The kind of token. */ ENUM_BITFIELD (cpp_ttype) type : 8; /* If this token is a keyword, this value indicates which keyword. Otherwise, this value is RID_MAX. */ ENUM_BITFIELD (rid) keyword : 8; /* Token flags. */ unsigned char flags; /* The value associated with this token, if any. */ tree value; /* The location at which this token was found. */ location_t location; } cp_token; /* The number of tokens in a single token block. Computed so that cp_token_block fits in a 512B allocation unit. */ #define CP_TOKEN_BLOCK_NUM_TOKENS ((512 - 3*sizeof (char*))/sizeof (cp_token)) /* A group of tokens. These groups are chained together to store large numbers of tokens. (For example, a token block is created when the body of an inline member function is first encountered; the tokens are processed later after the class definition is complete.) This somewhat ungainly data structure (as opposed to, say, a variable-length array), is used due to constraints imposed by the current garbage-collection methodology. If it is made more flexible, we could perhaps simplify the data structures involved. */ typedef struct cp_token_block GTY (()) { /* The tokens. */ cp_token tokens[CP_TOKEN_BLOCK_NUM_TOKENS]; /* The number of tokens in this block. */ size_t num_tokens; /* The next token block in the chain. */ struct cp_token_block *next; /* The previous block in the chain. */ struct cp_token_block *prev; } cp_token_block; typedef struct cp_token_cache GTY (()) { /* The first block in the cache. NULL if there are no tokens in the cache. */ cp_token_block *first; /* The last block in the cache. NULL If there are no tokens in the cache. */ cp_token_block *last; } cp_token_cache; /* Prototypes. */ static cp_token_cache *cp_token_cache_new (void); static void cp_token_cache_push_token (cp_token_cache *, cp_token *); /* Create a new cp_token_cache. */ static cp_token_cache * cp_token_cache_new (void) { return ggc_alloc_cleared (sizeof (cp_token_cache)); } /* Add *TOKEN to *CACHE. */ static void cp_token_cache_push_token (cp_token_cache *cache, cp_token *token) { cp_token_block *b = cache->last; /* See if we need to allocate a new token block. */ if (!b || b->num_tokens == CP_TOKEN_BLOCK_NUM_TOKENS) { b = ggc_alloc_cleared (sizeof (cp_token_block)); b->prev = cache->last; if (cache->last) { cache->last->next = b; cache->last = b; } else cache->first = cache->last = b; } /* Add this token to the current token block. */ b->tokens[b->num_tokens++] = *token; } /* The cp_lexer structure represents the C++ lexer. It is responsible for managing the token stream from the preprocessor and supplying it to the parser. */ typedef struct cp_lexer GTY (()) { /* The memory allocated for the buffer. Never NULL. */ cp_token * GTY ((length ("(%h.buffer_end - %h.buffer)"))) buffer; /* A pointer just past the end of the memory allocated for the buffer. */ cp_token * GTY ((skip (""))) buffer_end; /* The first valid token in the buffer, or NULL if none. */ cp_token * GTY ((skip (""))) first_token; /* The next available token. If NEXT_TOKEN is NULL, then there are no more available tokens. */ cp_token * GTY ((skip (""))) next_token; /* A pointer just past the last available token. If FIRST_TOKEN is NULL, however, there are no available tokens, and then this location is simply the place in which the next token read will be placed. If LAST_TOKEN == FIRST_TOKEN, then the buffer is full. When the LAST_TOKEN == BUFFER, then the last token is at the highest memory address in the BUFFER. */ cp_token * GTY ((skip (""))) last_token; /* A stack indicating positions at which cp_lexer_save_tokens was called. The top entry is the most recent position at which we began saving tokens. The entries are differences in token position between FIRST_TOKEN and the first saved token. If the stack is non-empty, we are saving tokens. When a token is consumed, the NEXT_TOKEN pointer will move, but the FIRST_TOKEN pointer will not. The token stream will be preserved so that it can be reexamined later. If the stack is empty, then we are not saving tokens. Whenever a token is consumed, the FIRST_TOKEN pointer will be moved, and the consumed token will be gone forever. */ varray_type saved_tokens; /* The STRING_CST tokens encountered while processing the current string literal. */ varray_type string_tokens; /* True if we should obtain more tokens from the preprocessor; false if we are processing a saved token cache. */ bool main_lexer_p; /* True if we should output debugging information. */ bool debugging_p; /* The next lexer in a linked list of lexers. */ struct cp_lexer *next; } cp_lexer; /* Prototypes. */ static cp_lexer *cp_lexer_new_main (void); static cp_lexer *cp_lexer_new_from_tokens (struct cp_token_cache *); static int cp_lexer_saving_tokens (const cp_lexer *); static cp_token *cp_lexer_next_token (cp_lexer *, cp_token *); static cp_token *cp_lexer_prev_token (cp_lexer *, cp_token *); static ptrdiff_t cp_lexer_token_difference (cp_lexer *, cp_token *, cp_token *); static cp_token *cp_lexer_read_token (cp_lexer *); static void cp_lexer_maybe_grow_buffer (cp_lexer *); static void cp_lexer_get_preprocessor_token (cp_lexer *, cp_token *); static cp_token *cp_lexer_peek_token (cp_lexer *); static cp_token *cp_lexer_peek_nth_token (cp_lexer *, size_t); static inline bool cp_lexer_next_token_is (cp_lexer *, enum cpp_ttype); static bool cp_lexer_next_token_is_not (cp_lexer *, enum cpp_ttype); static bool cp_lexer_next_token_is_keyword (cp_lexer *, enum rid); static cp_token *cp_lexer_consume_token (cp_lexer *); static void cp_lexer_purge_token (cp_lexer *); static void cp_lexer_purge_tokens_after (cp_lexer *, cp_token *); static void cp_lexer_save_tokens (cp_lexer *); static void cp_lexer_commit_tokens (cp_lexer *); static void cp_lexer_rollback_tokens (cp_lexer *); static inline void cp_lexer_set_source_position_from_token (cp_lexer *, const cp_token *); static void cp_lexer_print_token (FILE *, cp_token *); static inline bool cp_lexer_debugging_p (cp_lexer *); static void cp_lexer_start_debugging (cp_lexer *) ATTRIBUTE_UNUSED; static void cp_lexer_stop_debugging (cp_lexer *) ATTRIBUTE_UNUSED; /* Manifest constants. */ #define CP_TOKEN_BUFFER_SIZE 5 #define CP_SAVED_TOKENS_SIZE 5 /* A token type for keywords, as opposed to ordinary identifiers. */ #define CPP_KEYWORD ((enum cpp_ttype) (N_TTYPES + 1)) /* A token type for template-ids. If a template-id is processed while parsing tentatively, it is replaced with a CPP_TEMPLATE_ID token; the value of the CPP_TEMPLATE_ID is whatever was returned by cp_parser_template_id. */ #define CPP_TEMPLATE_ID ((enum cpp_ttype) (CPP_KEYWORD + 1)) /* A token type for nested-name-specifiers. If a nested-name-specifier is processed while parsing tentatively, it is replaced with a CPP_NESTED_NAME_SPECIFIER token; the value of the CPP_NESTED_NAME_SPECIFIER is whatever was returned by cp_parser_nested_name_specifier_opt. */ #define CPP_NESTED_NAME_SPECIFIER ((enum cpp_ttype) (CPP_TEMPLATE_ID + 1)) /* A token type for tokens that are not tokens at all; these are used to mark the end of a token block. */ #define CPP_NONE (CPP_NESTED_NAME_SPECIFIER + 1) /* Variables. */ /* The stream to which debugging output should be written. */ static FILE *cp_lexer_debug_stream; /* Create a new main C++ lexer, the lexer that gets tokens from the preprocessor. */ static cp_lexer * cp_lexer_new_main (void) { cp_lexer *lexer; cp_token first_token; /* It's possible that lexing the first token will load a PCH file, which is a GC collection point. So we have to grab the first token before allocating any memory. */ cp_lexer_get_preprocessor_token (NULL, &first_token); c_common_no_more_pch (); /* Allocate the memory. */ lexer = ggc_alloc_cleared (sizeof (cp_lexer)); /* Create the circular buffer. */ lexer->buffer = ggc_calloc (CP_TOKEN_BUFFER_SIZE, sizeof (cp_token)); lexer->buffer_end = lexer->buffer + CP_TOKEN_BUFFER_SIZE; /* There is one token in the buffer. */ lexer->last_token = lexer->buffer + 1; lexer->first_token = lexer->buffer; lexer->next_token = lexer->buffer; memcpy (lexer->buffer, &first_token, sizeof (cp_token)); /* This lexer obtains more tokens by calling c_lex. */ lexer->main_lexer_p = true; /* Create the SAVED_TOKENS stack. */ VARRAY_INT_INIT (lexer->saved_tokens, CP_SAVED_TOKENS_SIZE, "saved_tokens"); /* Create the STRINGS array. */ VARRAY_TREE_INIT (lexer->string_tokens, 32, "strings"); /* Assume we are not debugging. */ lexer->debugging_p = false; return lexer; } /* Create a new lexer whose token stream is primed with the TOKENS. When these tokens are exhausted, no new tokens will be read. */ static cp_lexer * cp_lexer_new_from_tokens (cp_token_cache *tokens) { cp_lexer *lexer; cp_token *token; cp_token_block *block; ptrdiff_t num_tokens; /* Allocate the memory. */ lexer = ggc_alloc_cleared (sizeof (cp_lexer)); /* Create a new buffer, appropriately sized. */ num_tokens = 0; for (block = tokens->first; block != NULL; block = block->next) num_tokens += block->num_tokens; lexer->buffer = ggc_alloc (num_tokens * sizeof (cp_token)); lexer->buffer_end = lexer->buffer + num_tokens; /* Install the tokens. */ token = lexer->buffer; for (block = tokens->first; block != NULL; block = block->next) { memcpy (token, block->tokens, block->num_tokens * sizeof (cp_token)); token += block->num_tokens; } /* The FIRST_TOKEN is the beginning of the buffer. */ lexer->first_token = lexer->buffer; /* The next available token is also at the beginning of the buffer. */ lexer->next_token = lexer->buffer; /* The buffer is full. */ lexer->last_token = lexer->first_token; /* This lexer doesn't obtain more tokens. */ lexer->main_lexer_p = false; /* Create the SAVED_TOKENS stack. */ VARRAY_INT_INIT (lexer->saved_tokens, CP_SAVED_TOKENS_SIZE, "saved_tokens"); /* Create the STRINGS array. */ VARRAY_TREE_INIT (lexer->string_tokens, 32, "strings"); /* Assume we are not debugging. */ lexer->debugging_p = false; return lexer; } /* Returns nonzero if debugging information should be output. */ static inline bool cp_lexer_debugging_p (cp_lexer *lexer) { return lexer->debugging_p; } /* Set the current source position from the information stored in TOKEN. */ static inline void cp_lexer_set_source_position_from_token (cp_lexer *lexer ATTRIBUTE_UNUSED , const cp_token *token) { /* Ideally, the source position information would not be a global variable, but it is. */ /* Update the line number. */ if (token->type != CPP_EOF) input_location = token->location; } /* TOKEN points into the circular token buffer. Return a pointer to the next token in the buffer. */ static inline cp_token * cp_lexer_next_token (cp_lexer* lexer, cp_token* token) { token++; if (token == lexer->buffer_end) token = lexer->buffer; return token; } /* TOKEN points into the circular token buffer. Return a pointer to the previous token in the buffer. */ static inline cp_token * cp_lexer_prev_token (cp_lexer* lexer, cp_token* token) { if (token == lexer->buffer) token = lexer->buffer_end; return token - 1; } /* nonzero if we are presently saving tokens. */ static int cp_lexer_saving_tokens (const cp_lexer* lexer) { return VARRAY_ACTIVE_SIZE (lexer->saved_tokens) != 0; } /* Return a pointer to the token that is N tokens beyond TOKEN in the buffer. */ static cp_token * cp_lexer_advance_token (cp_lexer *lexer, cp_token *token, ptrdiff_t n) { token += n; if (token >= lexer->buffer_end) token = lexer->buffer + (token - lexer->buffer_end); return token; } /* Returns the number of times that START would have to be incremented to reach FINISH. If START and FINISH are the same, returns zero. */ static ptrdiff_t cp_lexer_token_difference (cp_lexer* lexer, cp_token* start, cp_token* finish) { if (finish >= start) return finish - start; else return ((lexer->buffer_end - lexer->buffer) - (start - finish)); } /* Obtain another token from the C preprocessor and add it to the token buffer. Returns the newly read token. */ static cp_token * cp_lexer_read_token (cp_lexer* lexer) { cp_token *token; /* Make sure there is room in the buffer. */ cp_lexer_maybe_grow_buffer (lexer); /* If there weren't any tokens, then this one will be the first. */ if (!lexer->first_token) lexer->first_token = lexer->last_token; /* Similarly, if there were no available tokens, there is one now. */ if (!lexer->next_token) lexer->next_token = lexer->last_token; /* Figure out where we're going to store the new token. */ token = lexer->last_token; /* Get a new token from the preprocessor. */ cp_lexer_get_preprocessor_token (lexer, token); /* Increment LAST_TOKEN. */ lexer->last_token = cp_lexer_next_token (lexer, token); /* Strings should have type `const char []'. Right now, we will have an ARRAY_TYPE that is constant rather than an array of constant elements. FIXME: Make fix_string_type get this right in the first place. */ if ((token->type == CPP_STRING || token->type == CPP_WSTRING) && flag_const_strings) { tree type; /* Get the current type. It will be an ARRAY_TYPE. */ type = TREE_TYPE (token->value); /* Use build_cplus_array_type to rebuild the array, thereby getting the right type. */ type = build_cplus_array_type (TREE_TYPE (type), TYPE_DOMAIN (type)); /* Reset the type of the token. */ TREE_TYPE (token->value) = type; } return token; } /* If the circular buffer is full, make it bigger. */ static void cp_lexer_maybe_grow_buffer (cp_lexer* lexer) { /* If the buffer is full, enlarge it. */ if (lexer->last_token == lexer->first_token) { cp_token *new_buffer; cp_token *old_buffer; cp_token *new_first_token; ptrdiff_t buffer_length; size_t num_tokens_to_copy; /* Remember the current buffer pointer. It will become invalid, but we will need to do pointer arithmetic involving this value. */ old_buffer = lexer->buffer; /* Compute the current buffer size. */ buffer_length = lexer->buffer_end - lexer->buffer; /* Allocate a buffer twice as big. */ new_buffer = ggc_realloc (lexer->buffer, 2 * buffer_length * sizeof (cp_token)); /* Because the buffer is circular, logically consecutive tokens are not necessarily placed consecutively in memory. Therefore, we must keep move the tokens that were before FIRST_TOKEN to the second half of the newly allocated buffer. */ num_tokens_to_copy = (lexer->first_token - old_buffer); memcpy (new_buffer + buffer_length, new_buffer, num_tokens_to_copy * sizeof (cp_token)); /* Clear the rest of the buffer. We never look at this storage, but the garbage collector may. */ memset (new_buffer + buffer_length + num_tokens_to_copy, 0, (buffer_length - num_tokens_to_copy) * sizeof (cp_token)); /* Now recompute all of the buffer pointers. */ new_first_token = new_buffer + (lexer->first_token - old_buffer); if (lexer->next_token != NULL) { ptrdiff_t next_token_delta; if (lexer->next_token > lexer->first_token) next_token_delta = lexer->next_token - lexer->first_token; else next_token_delta = buffer_length - (lexer->first_token - lexer->next_token); lexer->next_token = new_first_token + next_token_delta; } lexer->last_token = new_first_token + buffer_length; lexer->buffer = new_buffer; lexer->buffer_end = new_buffer + buffer_length * 2; lexer->first_token = new_first_token; } } /* Store the next token from the preprocessor in *TOKEN. */ static void cp_lexer_get_preprocessor_token (cp_lexer *lexer ATTRIBUTE_UNUSED , cp_token *token) { bool done; /* If this not the main lexer, return a terminating CPP_EOF token. */ if (lexer != NULL && !lexer->main_lexer_p) { token->type = CPP_EOF; token->location.line = 0; token->location.file = NULL; token->value = NULL_TREE; token->keyword = RID_MAX; return; } done = false; /* Keep going until we get a token we like. */ while (!done) { /* Get a new token from the preprocessor. */ token->type = c_lex_with_flags (&token->value, &token->flags); /* Issue messages about tokens we cannot process. */ switch (token->type) { case CPP_ATSIGN: case CPP_HASH: case CPP_PASTE: error ("invalid token"); break; default: /* This is a good token, so we exit the loop. */ done = true; break; } } /* Now we've got our token. */ token->location = input_location; /* Check to see if this token is a keyword. */ if (token->type == CPP_NAME && C_IS_RESERVED_WORD (token->value)) { /* Mark this token as a keyword. */ token->type = CPP_KEYWORD; /* Record which keyword. */ token->keyword = C_RID_CODE (token->value); /* Update the value. Some keywords are mapped to particular entities, rather than simply having the value of the corresponding IDENTIFIER_NODE. For example, `__const' is mapped to `const'. */ token->value = ridpointers[token->keyword]; } else token->keyword = RID_MAX; } /* Return a pointer to the next token in the token stream, but do not consume it. */ static cp_token * cp_lexer_peek_token (cp_lexer* lexer) { cp_token *token; /* If there are no tokens, read one now. */ if (!lexer->next_token) cp_lexer_read_token (lexer); /* Provide debugging output. */ if (cp_lexer_debugging_p (lexer)) { fprintf (cp_lexer_debug_stream, "cp_lexer: peeking at token: "); cp_lexer_print_token (cp_lexer_debug_stream, lexer->next_token); fprintf (cp_lexer_debug_stream, "\n"); } token = lexer->next_token; cp_lexer_set_source_position_from_token (lexer, token); return token; } /* Return true if the next token has the indicated TYPE. */ static bool cp_lexer_next_token_is (cp_lexer* lexer, enum cpp_ttype type) { cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (lexer); /* Check to see if it has the indicated TYPE. */ return token->type == type; } /* Return true if the next token does not have the indicated TYPE. */ static bool cp_lexer_next_token_is_not (cp_lexer* lexer, enum cpp_ttype type) { return !cp_lexer_next_token_is (lexer, type); } /* Return true if the next token is the indicated KEYWORD. */ static bool cp_lexer_next_token_is_keyword (cp_lexer* lexer, enum rid keyword) { cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (lexer); /* Check to see if it is the indicated keyword. */ return token->keyword == keyword; } /* Return a pointer to the Nth token in the token stream. If N is 1, then this is precisely equivalent to cp_lexer_peek_token. */ static cp_token * cp_lexer_peek_nth_token (cp_lexer* lexer, size_t n) { cp_token *token; /* N is 1-based, not zero-based. */ my_friendly_assert (n > 0, 20000224); /* Skip ahead from NEXT_TOKEN, reading more tokens as necessary. */ token = lexer->next_token; /* If there are no tokens in the buffer, get one now. */ if (!token) { cp_lexer_read_token (lexer); token = lexer->next_token; } /* Now, read tokens until we have enough. */ while (--n > 0) { /* Advance to the next token. */ token = cp_lexer_next_token (lexer, token); /* If that's all the tokens we have, read a new one. */ if (token == lexer->last_token) token = cp_lexer_read_token (lexer); } return token; } /* Consume the next token. The pointer returned is valid only until another token is read. Callers should preserve copy the token explicitly if they will need its value for a longer period of time. */ static cp_token * cp_lexer_consume_token (cp_lexer* lexer) { cp_token *token; /* If there are no tokens, read one now. */ if (!lexer->next_token) cp_lexer_read_token (lexer); /* Remember the token we'll be returning. */ token = lexer->next_token; /* Increment NEXT_TOKEN. */ lexer->next_token = cp_lexer_next_token (lexer, lexer->next_token); /* Check to see if we're all out of tokens. */ if (lexer->next_token == lexer->last_token) lexer->next_token = NULL; /* If we're not saving tokens, then move FIRST_TOKEN too. */ if (!cp_lexer_saving_tokens (lexer)) { /* If there are no tokens available, set FIRST_TOKEN to NULL. */ if (!lexer->next_token) lexer->first_token = NULL; else lexer->first_token = lexer->next_token; } /* Provide debugging output. */ if (cp_lexer_debugging_p (lexer)) { fprintf (cp_lexer_debug_stream, "cp_lexer: consuming token: "); cp_lexer_print_token (cp_lexer_debug_stream, token); fprintf (cp_lexer_debug_stream, "\n"); } return token; } /* Permanently remove the next token from the token stream. There must be a valid next token already; this token never reads additional tokens from the preprocessor. */ static void cp_lexer_purge_token (cp_lexer *lexer) { cp_token *token; cp_token *next_token; token = lexer->next_token; while (true) { next_token = cp_lexer_next_token (lexer, token); if (next_token == lexer->last_token) break; *token = *next_token; token = next_token; } lexer->last_token = token; /* The token purged may have been the only token remaining; if so, clear NEXT_TOKEN. */ if (lexer->next_token == token) lexer->next_token = NULL; } /* Permanently remove all tokens after TOKEN, up to, but not including, the token that will be returned next by cp_lexer_peek_token. */ static void cp_lexer_purge_tokens_after (cp_lexer *lexer, cp_token *token) { cp_token *peek; cp_token *t1; cp_token *t2; if (lexer->next_token) { /* Copy the tokens that have not yet been read to the location immediately following TOKEN. */ t1 = cp_lexer_next_token (lexer, token); t2 = peek = cp_lexer_peek_token (lexer); /* Move tokens into the vacant area between TOKEN and PEEK. */ while (t2 != lexer->last_token) { *t1 = *t2; t1 = cp_lexer_next_token (lexer, t1); t2 = cp_lexer_next_token (lexer, t2); } /* Now, the next available token is right after TOKEN. */ lexer->next_token = cp_lexer_next_token (lexer, token); /* And the last token is wherever we ended up. */ lexer->last_token = t1; } else { /* There are no tokens in the buffer, so there is nothing to copy. The last token in the buffer is TOKEN itself. */ lexer->last_token = cp_lexer_next_token (lexer, token); } } /* Begin saving tokens. All tokens consumed after this point will be preserved. */ static void cp_lexer_save_tokens (cp_lexer* lexer) { /* Provide debugging output. */ if (cp_lexer_debugging_p (lexer)) fprintf (cp_lexer_debug_stream, "cp_lexer: saving tokens\n"); /* Make sure that LEXER->NEXT_TOKEN is non-NULL so that we can restore the tokens if required. */ if (!lexer->next_token) cp_lexer_read_token (lexer); VARRAY_PUSH_INT (lexer->saved_tokens, cp_lexer_token_difference (lexer, lexer->first_token, lexer->next_token)); } /* Commit to the portion of the token stream most recently saved. */ static void cp_lexer_commit_tokens (cp_lexer* lexer) { /* Provide debugging output. */ if (cp_lexer_debugging_p (lexer)) fprintf (cp_lexer_debug_stream, "cp_lexer: committing tokens\n"); VARRAY_POP (lexer->saved_tokens); } /* Return all tokens saved since the last call to cp_lexer_save_tokens to the token stream. Stop saving tokens. */ static void cp_lexer_rollback_tokens (cp_lexer* lexer) { size_t delta; /* Provide debugging output. */ if (cp_lexer_debugging_p (lexer)) fprintf (cp_lexer_debug_stream, "cp_lexer: restoring tokens\n"); /* Find the token that was the NEXT_TOKEN when we started saving tokens. */ delta = VARRAY_TOP_INT(lexer->saved_tokens); /* Make it the next token again now. */ lexer->next_token = cp_lexer_advance_token (lexer, lexer->first_token, delta); /* It might be the case that there were no tokens when we started saving tokens, but that there are some tokens now. */ if (!lexer->next_token && lexer->first_token) lexer->next_token = lexer->first_token; /* Stop saving tokens. */ VARRAY_POP (lexer->saved_tokens); } /* Print a representation of the TOKEN on the STREAM. */ static void cp_lexer_print_token (FILE * stream, cp_token* token) { const char *token_type = NULL; /* Figure out what kind of token this is. */ switch (token->type) { case CPP_EQ: token_type = "EQ"; break; case CPP_COMMA: token_type = "COMMA"; break; case CPP_OPEN_PAREN: token_type = "OPEN_PAREN"; break; case CPP_CLOSE_PAREN: token_type = "CLOSE_PAREN"; break; case CPP_OPEN_BRACE: token_type = "OPEN_BRACE"; break; case CPP_CLOSE_BRACE: token_type = "CLOSE_BRACE"; break; case CPP_SEMICOLON: token_type = "SEMICOLON"; break; case CPP_NAME: token_type = "NAME"; break; case CPP_EOF: token_type = "EOF"; break; case CPP_KEYWORD: token_type = "keyword"; break; /* This is not a token that we know how to handle yet. */ default: break; } /* If we have a name for the token, print it out. Otherwise, we simply give the numeric code. */ if (token_type) fprintf (stream, "%s", token_type); else fprintf (stream, "%d", token->type); /* And, for an identifier, print the identifier name. */ if (token->type == CPP_NAME /* Some keywords have a value that is not an IDENTIFIER_NODE. For example, `struct' is mapped to an INTEGER_CST. */ || (token->type == CPP_KEYWORD && TREE_CODE (token->value) == IDENTIFIER_NODE)) fprintf (stream, " %s", IDENTIFIER_POINTER (token->value)); } /* Start emitting debugging information. */ static void cp_lexer_start_debugging (cp_lexer* lexer) { ++lexer->debugging_p; } /* Stop emitting debugging information. */ static void cp_lexer_stop_debugging (cp_lexer* lexer) { --lexer->debugging_p; } /* The parser. */ /* Overview -------- A cp_parser parses the token stream as specified by the C++ grammar. Its job is purely parsing, not semantic analysis. For example, the parser breaks the token stream into declarators, expressions, statements, and other similar syntactic constructs. It does not check that the types of the expressions on either side of an assignment-statement are compatible, or that a function is not declared with a parameter of type `void'. The parser invokes routines elsewhere in the compiler to perform semantic analysis and to build up the abstract syntax tree for the code processed. The parser (and the template instantiation code, which is, in a way, a close relative of parsing) are the only parts of the compiler that should be calling push_scope and pop_scope, or related functions. The parser (and template instantiation code) keeps track of what scope is presently active; everything else should simply honor that. (The code that generates static initializers may also need to set the scope, in order to check access control correctly when emitting the initializers.) Methodology ----------- The parser is of the standard recursive-descent variety. Upcoming tokens in the token stream are examined in order to determine which production to use when parsing a non-terminal. Some C++ constructs require arbitrary look ahead to disambiguate. For example, it is impossible, in the general case, to tell whether a statement is an expression or declaration without scanning the entire statement. Therefore, the parser is capable of "parsing tentatively." When the parser is not sure what construct comes next, it enters this mode. Then, while we attempt to parse the construct, the parser queues up error messages, rather than issuing them immediately, and saves the tokens it consumes. If the construct is parsed successfully, the parser "commits", i.e., it issues any queued error messages and the tokens that were being preserved are permanently discarded. If, however, the construct is not parsed successfully, the parser rolls back its state completely so that it can resume parsing using a different alternative. Future Improvements ------------------- The performance of the parser could probably be improved substantially. Some possible improvements include: - The expression parser recurses through the various levels of precedence as specified in the grammar, rather than using an operator-precedence technique. Therefore, parsing a simple identifier requires multiple recursive calls. - We could often eliminate the need to parse tentatively by looking ahead a little bit. In some places, this approach might not entirely eliminate the need to parse tentatively, but it might still speed up the average case. */ /* Flags that are passed to some parsing functions. These values can be bitwise-ored together. */ typedef enum cp_parser_flags { /* No flags. */ CP_PARSER_FLAGS_NONE = 0x0, /* The construct is optional. If it is not present, then no error should be issued. */ CP_PARSER_FLAGS_OPTIONAL = 0x1, /* When parsing a type-specifier, do not allow user-defined types. */ CP_PARSER_FLAGS_NO_USER_DEFINED_TYPES = 0x2 } cp_parser_flags; /* The different kinds of declarators we want to parse. */ typedef enum cp_parser_declarator_kind { /* We want an abstract declartor. */ CP_PARSER_DECLARATOR_ABSTRACT, /* We want a named declarator. */ CP_PARSER_DECLARATOR_NAMED, /* We don't mind, but the name must be an unqualified-id. */ CP_PARSER_DECLARATOR_EITHER } cp_parser_declarator_kind; /* A mapping from a token type to a corresponding tree node type. */ typedef struct cp_parser_token_tree_map_node { /* The token type. */ ENUM_BITFIELD (cpp_ttype) token_type : 8; /* The corresponding tree code. */ ENUM_BITFIELD (tree_code) tree_type : 8; } cp_parser_token_tree_map_node; /* A complete map consists of several ordinary entries, followed by a terminator. The terminating entry has a token_type of CPP_EOF. */ typedef cp_parser_token_tree_map_node cp_parser_token_tree_map[]; /* The status of a tentative parse. */ typedef enum cp_parser_status_kind { /* No errors have occurred. */ CP_PARSER_STATUS_KIND_NO_ERROR, /* An error has occurred. */ CP_PARSER_STATUS_KIND_ERROR, /* We are committed to this tentative parse, whether or not an error has occurred. */ CP_PARSER_STATUS_KIND_COMMITTED } cp_parser_status_kind; /* Context that is saved and restored when parsing tentatively. */ typedef struct cp_parser_context GTY (()) { /* If this is a tentative parsing context, the status of the tentative parse. */ enum cp_parser_status_kind status; /* If non-NULL, we have just seen a `x->' or `x.' expression. Names that are looked up in this context must be looked up both in the scope given by OBJECT_TYPE (the type of `x' or `*x') and also in the context of the containing expression. */ tree object_type; /* The next parsing context in the stack. */ struct cp_parser_context *next; } cp_parser_context; /* Prototypes. */ /* Constructors and destructors. */ static cp_parser_context *cp_parser_context_new (cp_parser_context *); /* Class variables. */ static GTY((deletable (""))) cp_parser_context* cp_parser_context_free_list; /* Constructors and destructors. */ /* Construct a new context. The context below this one on the stack is given by NEXT. */ static cp_parser_context * cp_parser_context_new (cp_parser_context* next) { cp_parser_context *context; /* Allocate the storage. */ if (cp_parser_context_free_list != NULL) { /* Pull the first entry from the free list. */ context = cp_parser_context_free_list; cp_parser_context_free_list = context->next; memset (context, 0, sizeof (*context)); } else context = ggc_alloc_cleared (sizeof (cp_parser_context)); /* No errors have occurred yet in this context. */ context->status = CP_PARSER_STATUS_KIND_NO_ERROR; /* If this is not the bottomost context, copy information that we need from the previous context. */ if (next) { /* If, in the NEXT context, we are parsing an `x->' or `x.' expression, then we are parsing one in this context, too. */ context->object_type = next->object_type; /* Thread the stack. */ context->next = next; } return context; } /* The cp_parser structure represents the C++ parser. */ typedef struct cp_parser GTY(()) { /* The lexer from which we are obtaining tokens. */ cp_lexer *lexer; /* The scope in which names should be looked up. If NULL_TREE, then we look up names in the scope that is currently open in the source program. If non-NULL, this is either a TYPE or NAMESPACE_DECL for the scope in which we should look. This value is not cleared automatically after a name is looked up, so we must be careful to clear it before starting a new look up sequence. (If it is not cleared, then `X::Y' followed by `Z' will look up `Z' in the scope of `X', rather than the current scope.) Unfortunately, it is difficult to tell when name lookup is complete, because we sometimes peek at a token, look it up, and then decide not to consume it. */ tree scope; /* OBJECT_SCOPE and QUALIFYING_SCOPE give the scopes in which the last lookup took place. OBJECT_SCOPE is used if an expression like "x->y" or "x.y" was used; it gives the type of "*x" or "x", respectively. QUALIFYING_SCOPE is used for an expression of the form "X::Y"; it refers to X. */ tree object_scope; tree qualifying_scope; /* A stack of parsing contexts. All but the bottom entry on the stack will be tentative contexts. We parse tentatively in order to determine which construct is in use in some situations. For example, in order to determine whether a statement is an expression-statement or a declaration-statement we parse it tentatively as a declaration-statement. If that fails, we then reparse the same token stream as an expression-statement. */ cp_parser_context *context; /* True if we are parsing GNU C++. If this flag is not set, then GNU extensions are not recognized. */ bool allow_gnu_extensions_p; /* TRUE if the `>' token should be interpreted as the greater-than operator. FALSE if it is the end of a template-id or template-parameter-list. */ bool greater_than_is_operator_p; /* TRUE if default arguments are allowed within a parameter list that starts at this point. FALSE if only a gnu extension makes them permissible. */ bool default_arg_ok_p; /* TRUE if we are parsing an integral constant-expression. See [expr.const] for a precise definition. */ bool integral_constant_expression_p; /* TRUE if we are parsing an integral constant-expression -- but a non-constant expression should be permitted as well. This flag is used when parsing an array bound so that GNU variable-length arrays are tolerated. */ bool allow_non_integral_constant_expression_p; /* TRUE if ALLOW_NON_CONSTANT_EXPRESSION_P is TRUE and something has been seen that makes the expression non-constant. */ bool non_integral_constant_expression_p; /* TRUE if we are parsing the argument to "__offsetof__". */ bool in_offsetof_p; /* TRUE if local variable names and `this' are forbidden in the current context. */ bool local_variables_forbidden_p; /* TRUE if the declaration we are parsing is part of a linkage-specification of the form `extern string-literal declaration'. */ bool in_unbraced_linkage_specification_p; /* TRUE if we are presently parsing a declarator, after the direct-declarator. */ bool in_declarator_p; /* TRUE if we are presently parsing a template-argument-list. */ bool in_template_argument_list_p; /* TRUE if we are presently parsing the body of an iteration-statement. */ bool in_iteration_statement_p; /* TRUE if we are presently parsing the body of a switch statement. */ bool in_switch_statement_p; /* TRUE if we are parsing a type-id in an expression context. In such a situation, both "type (expr)" and "type (type)" are valid alternatives. */ bool in_type_id_in_expr_p; /* If non-NULL, then we are parsing a construct where new type definitions are not permitted. The string stored here will be issued as an error message if a type is defined. */ const char *type_definition_forbidden_message; /* A list of lists. The outer list is a stack, used for member functions of local classes. At each level there are two sub-list, one on TREE_VALUE and one on TREE_PURPOSE. Each of those sub-lists has a FUNCTION_DECL or TEMPLATE_DECL on their TREE_VALUE's. The functions are chained in reverse declaration order. The TREE_PURPOSE sublist contains those functions with default arguments that need post processing, and the TREE_VALUE sublist contains those functions with definitions that need post processing. These lists can only be processed once the outermost class being defined is complete. */ tree unparsed_functions_queues; /* The number of classes whose definitions are currently in progress. */ unsigned num_classes_being_defined; /* The number of template parameter lists that apply directly to the current declaration. */ unsigned num_template_parameter_lists; } cp_parser; /* The type of a function that parses some kind of expression. */ typedef tree (*cp_parser_expression_fn) (cp_parser *); /* Prototypes. */ /* Constructors and destructors. */ static cp_parser *cp_parser_new (void); /* Routines to parse various constructs. Those that return `tree' will return the error_mark_node (rather than NULL_TREE) if a parse error occurs, unless otherwise noted. Sometimes, they will return an ordinary node if error-recovery was attempted, even though a parse error occurred. So, to check whether or not a parse error occurred, you should always use cp_parser_error_occurred. If the construct is optional (indicated either by an `_opt' in the name of the function that does the parsing or via a FLAGS parameter), then NULL_TREE is returned if the construct is not present. */ /* Lexical conventions [gram.lex] */ static tree cp_parser_identifier (cp_parser *); /* Basic concepts [gram.basic] */ static bool cp_parser_translation_unit (cp_parser *); /* Expressions [gram.expr] */ static tree cp_parser_primary_expression (cp_parser *, cp_id_kind *, tree *); static tree cp_parser_id_expression (cp_parser *, bool, bool, bool *, bool); static tree cp_parser_unqualified_id (cp_parser *, bool, bool, bool); static tree cp_parser_nested_name_specifier_opt (cp_parser *, bool, bool, bool, bool); static tree cp_parser_nested_name_specifier (cp_parser *, bool, bool, bool, bool); static tree cp_parser_class_or_namespace_name (cp_parser *, bool, bool, bool, bool, bool); static tree cp_parser_postfix_expression (cp_parser *, bool); static tree cp_parser_parenthesized_expression_list (cp_parser *, bool, bool *); static void cp_parser_pseudo_destructor_name (cp_parser *, tree *, tree *); static tree cp_parser_unary_expression (cp_parser *, bool); static enum tree_code cp_parser_unary_operator (cp_token *); static tree cp_parser_new_expression (cp_parser *); static tree cp_parser_new_placement (cp_parser *); static tree cp_parser_new_type_id (cp_parser *); static tree cp_parser_new_declarator_opt (cp_parser *); static tree cp_parser_direct_new_declarator (cp_parser *); static tree cp_parser_new_initializer (cp_parser *); static tree cp_parser_delete_expression (cp_parser *); static tree cp_parser_cast_expression (cp_parser *, bool); static tree cp_parser_pm_expression (cp_parser *); static tree cp_parser_multiplicative_expression (cp_parser *); static tree cp_parser_additive_expression (cp_parser *); static tree cp_parser_shift_expression (cp_parser *); static tree cp_parser_relational_expression (cp_parser *); static tree cp_parser_equality_expression (cp_parser *); static tree cp_parser_and_expression (cp_parser *); static tree cp_parser_exclusive_or_expression (cp_parser *); static tree cp_parser_inclusive_or_expression (cp_parser *); static tree cp_parser_logical_and_expression (cp_parser *); static tree cp_parser_logical_or_expression (cp_parser *); static tree cp_parser_question_colon_clause (cp_parser *, tree); static tree cp_parser_assignment_expression (cp_parser *); static enum tree_code cp_parser_assignment_operator_opt (cp_parser *); static tree cp_parser_expression (cp_parser *); static tree cp_parser_constant_expression (cp_parser *, bool, bool *); /* Statements [gram.stmt.stmt] */ static void cp_parser_statement (cp_parser *, bool); static tree cp_parser_labeled_statement (cp_parser *, bool); static tree cp_parser_expression_statement (cp_parser *, bool); static tree cp_parser_compound_statement (cp_parser *, bool); static void cp_parser_statement_seq_opt (cp_parser *, bool); static tree cp_parser_selection_statement (cp_parser *); static tree cp_parser_condition (cp_parser *); static tree cp_parser_iteration_statement (cp_parser *); static void cp_parser_for_init_statement (cp_parser *); static tree cp_parser_jump_statement (cp_parser *); static void cp_parser_declaration_statement (cp_parser *); static tree cp_parser_implicitly_scoped_statement (cp_parser *); static void cp_parser_already_scoped_statement (cp_parser *); /* Declarations [gram.dcl.dcl] */ static void cp_parser_declaration_seq_opt (cp_parser *); static void cp_parser_declaration (cp_parser *); static void cp_parser_block_declaration (cp_parser *, bool); static void cp_parser_simple_declaration (cp_parser *, bool); static tree cp_parser_decl_specifier_seq (cp_parser *, cp_parser_flags, tree *, int *); static tree cp_parser_storage_class_specifier_opt (cp_parser *); static tree cp_parser_function_specifier_opt (cp_parser *); static tree cp_parser_type_specifier (cp_parser *, cp_parser_flags, bool, bool, int *, bool *); static tree cp_parser_simple_type_specifier (cp_parser *, cp_parser_flags, bool); static tree cp_parser_type_name (cp_parser *); static tree cp_parser_elaborated_type_specifier (cp_parser *, bool, bool); static tree cp_parser_enum_specifier (cp_parser *); static void cp_parser_enumerator_list (cp_parser *, tree); static void cp_parser_enumerator_definition (cp_parser *, tree); static tree cp_parser_namespace_name (cp_parser *); static void cp_parser_namespace_definition (cp_parser *); static void cp_parser_namespace_body (cp_parser *); static tree cp_parser_qualified_namespace_specifier (cp_parser *); static void cp_parser_namespace_alias_definition (cp_parser *); static void cp_parser_using_declaration (cp_parser *); static void cp_parser_using_directive (cp_parser *); static void cp_parser_asm_definition (cp_parser *); static void cp_parser_linkage_specification (cp_parser *); /* Declarators [gram.dcl.decl] */ static tree cp_parser_init_declarator (cp_parser *, tree, tree, bool, bool, int, bool *); static tree cp_parser_declarator (cp_parser *, cp_parser_declarator_kind, int *, bool *); static tree cp_parser_direct_declarator (cp_parser *, cp_parser_declarator_kind, int *); static enum tree_code cp_parser_ptr_operator (cp_parser *, tree *, tree *); static tree cp_parser_cv_qualifier_seq_opt (cp_parser *); static tree cp_parser_cv_qualifier_opt (cp_parser *); static tree cp_parser_declarator_id (cp_parser *); static tree cp_parser_type_id (cp_parser *); static tree cp_parser_type_specifier_seq (cp_parser *); static tree cp_parser_parameter_declaration_clause (cp_parser *); static tree cp_parser_parameter_declaration_list (cp_parser *); static tree cp_parser_parameter_declaration (cp_parser *, bool, bool *); static void cp_parser_function_body (cp_parser *); static tree cp_parser_initializer (cp_parser *, bool *, bool *); static tree cp_parser_initializer_clause (cp_parser *, bool *); static tree cp_parser_initializer_list (cp_parser *, bool *); static bool cp_parser_ctor_initializer_opt_and_function_body (cp_parser *); /* Classes [gram.class] */ static tree cp_parser_class_name (cp_parser *, bool, bool, bool, bool, bool, bool); static tree cp_parser_class_specifier (cp_parser *); static tree cp_parser_class_head (cp_parser *, bool *, tree *); static enum tag_types cp_parser_class_key (cp_parser *); static void cp_parser_member_specification_opt (cp_parser *); static void cp_parser_member_declaration (cp_parser *); static tree cp_parser_pure_specifier (cp_parser *); static tree cp_parser_constant_initializer (cp_parser *); /* Derived classes [gram.class.derived] */ static tree cp_parser_base_clause (cp_parser *); static tree cp_parser_base_specifier (cp_parser *); /* Special member functions [gram.special] */ static tree cp_parser_conversion_function_id (cp_parser *); static tree cp_parser_conversion_type_id (cp_parser *); static tree cp_parser_conversion_declarator_opt (cp_parser *); static bool cp_parser_ctor_initializer_opt (cp_parser *); static void cp_parser_mem_initializer_list (cp_parser *); static tree cp_parser_mem_initializer (cp_parser *); static tree cp_parser_mem_initializer_id (cp_parser *); /* Overloading [gram.over] */ static tree cp_parser_operator_function_id (cp_parser *); static tree cp_parser_operator (cp_parser *); /* Templates [gram.temp] */ static void cp_parser_template_declaration (cp_parser *, bool); static tree cp_parser_template_parameter_list (cp_parser *); static tree cp_parser_template_parameter (cp_parser *); static tree cp_parser_type_parameter (cp_parser *); static tree cp_parser_template_id (cp_parser *, bool, bool, bool); static tree cp_parser_template_name (cp_parser *, bool, bool, bool, bool *); static tree cp_parser_template_argument_list (cp_parser *); static tree cp_parser_template_argument (cp_parser *); static void cp_parser_explicit_instantiation (cp_parser *); static void cp_parser_explicit_specialization (cp_parser *); /* Exception handling [gram.exception] */ static tree cp_parser_try_block (cp_parser *); static bool cp_parser_function_try_block (cp_parser *); static void cp_parser_handler_seq (cp_parser *); static void cp_parser_handler (cp_parser *); static tree cp_parser_exception_declaration (cp_parser *); static tree cp_parser_throw_expression (cp_parser *); static tree cp_parser_exception_specification_opt (cp_parser *); static tree cp_parser_type_id_list (cp_parser *); /* GNU Extensions */ static tree cp_parser_asm_specification_opt (cp_parser *); static tree cp_parser_asm_operand_list (cp_parser *); static tree cp_parser_asm_clobber_list (cp_parser *); static tree cp_parser_attributes_opt (cp_parser *); static tree cp_parser_attribute_list (cp_parser *); static bool cp_parser_extension_opt (cp_parser *, int *); static void cp_parser_label_declaration (cp_parser *); /* Utility Routines */ static tree cp_parser_lookup_name (cp_parser *, tree, bool, bool, bool, bool); static tree cp_parser_lookup_name_simple (cp_parser *, tree); static tree cp_parser_maybe_treat_template_as_class (tree, bool); static bool cp_parser_check_declarator_template_parameters (cp_parser *, tree); static bool cp_parser_check_template_parameters (cp_parser *, unsigned); static tree cp_parser_simple_cast_expression (cp_parser *); static tree cp_parser_binary_expression (cp_parser *, const cp_parser_token_tree_map, cp_parser_expression_fn); static tree cp_parser_global_scope_opt (cp_parser *, bool); static bool cp_parser_constructor_declarator_p (cp_parser *, bool); static tree cp_parser_function_definition_from_specifiers_and_declarator (cp_parser *, tree, tree, tree); static tree cp_parser_function_definition_after_declarator (cp_parser *, bool); static void cp_parser_template_declaration_after_export (cp_parser *, bool); static tree cp_parser_single_declaration (cp_parser *, bool, bool *); static tree cp_parser_functional_cast (cp_parser *, tree); static tree cp_parser_save_member_function_body (cp_parser *, tree, tree, tree); static tree cp_parser_enclosed_template_argument_list (cp_parser *); static void cp_parser_save_default_args (cp_parser *, tree); static void cp_parser_late_parsing_for_member (cp_parser *, tree); static void cp_parser_late_parsing_default_args (cp_parser *, tree); static tree cp_parser_sizeof_operand (cp_parser *, enum rid); static bool cp_parser_declares_only_class_p (cp_parser *); static bool cp_parser_friend_p (tree); static cp_token *cp_parser_require (cp_parser *, enum cpp_ttype, const char *); static cp_token *cp_parser_require_keyword (cp_parser *, enum rid, const char *); static bool cp_parser_token_starts_function_definition_p (cp_token *); static bool cp_parser_next_token_starts_class_definition_p (cp_parser *); static bool cp_parser_next_token_ends_template_argument_p (cp_parser *); static bool cp_parser_nth_token_starts_template_argument_list_p (cp_parser *, size_t); static enum tag_types cp_parser_token_is_class_key (cp_token *); static void cp_parser_check_class_key (enum tag_types, tree type); static void cp_parser_check_access_in_redeclaration (tree type); static bool cp_parser_optional_template_keyword (cp_parser *); static void cp_parser_pre_parsed_nested_name_specifier (cp_parser *); static void cp_parser_cache_group (cp_parser *, cp_token_cache *, enum cpp_ttype, unsigned); static void cp_parser_parse_tentatively (cp_parser *); static void cp_parser_commit_to_tentative_parse (cp_parser *); static void cp_parser_abort_tentative_parse (cp_parser *); static bool cp_parser_parse_definitely (cp_parser *); static inline bool cp_parser_parsing_tentatively (cp_parser *); static bool cp_parser_committed_to_tentative_parse (cp_parser *); static void cp_parser_error (cp_parser *, const char *); static void cp_parser_name_lookup_error (cp_parser *, tree, tree, const char *); static bool cp_parser_simulate_error (cp_parser *); static void cp_parser_check_type_definition (cp_parser *); static void cp_parser_check_for_definition_in_return_type (tree, int); static void cp_parser_check_for_invalid_template_id (cp_parser *, tree); static bool cp_parser_non_integral_constant_expression (cp_parser *, const char *); static bool cp_parser_diagnose_invalid_type_name (cp_parser *); static int cp_parser_skip_to_closing_parenthesis (cp_parser *, bool, bool, bool); static void cp_parser_skip_to_end_of_statement (cp_parser *); static void cp_parser_consume_semicolon_at_end_of_statement (cp_parser *); static void cp_parser_skip_to_end_of_block_or_statement (cp_parser *); static void cp_parser_skip_to_closing_brace (cp_parser *); static void cp_parser_skip_until_found (cp_parser *, enum cpp_ttype, const char *); static bool cp_parser_error_occurred (cp_parser *); static bool cp_parser_allow_gnu_extensions_p (cp_parser *); static bool cp_parser_is_string_literal (cp_token *); static bool cp_parser_is_keyword (cp_token *, enum rid); /* Returns nonzero if we are parsing tentatively. */ static inline bool cp_parser_parsing_tentatively (cp_parser* parser) { return parser->context->next != NULL; } /* Returns nonzero if TOKEN is a string literal. */ static bool cp_parser_is_string_literal (cp_token* token) { return (token->type == CPP_STRING || token->type == CPP_WSTRING); } /* Returns nonzero if TOKEN is the indicated KEYWORD. */ static bool cp_parser_is_keyword (cp_token* token, enum rid keyword) { return token->keyword == keyword; } /* Issue the indicated error MESSAGE. */ static void cp_parser_error (cp_parser* parser, const char* message) { /* Output the MESSAGE -- unless we're parsing tentatively. */ if (!cp_parser_simulate_error (parser)) { cp_token *token; token = cp_lexer_peek_token (parser->lexer); c_parse_error (message, /* Because c_parser_error does not understand CPP_KEYWORD, keywords are treated like identifiers. */ (token->type == CPP_KEYWORD ? CPP_NAME : token->type), token->value); } } /* Issue an error about name-lookup failing. NAME is the IDENTIFIER_NODE DECL is the result of the lookup (as returned from cp_parser_lookup_name). DESIRED is the thing that we hoped to find. */ static void cp_parser_name_lookup_error (cp_parser* parser, tree name, tree decl, const char* desired) { /* If name lookup completely failed, tell the user that NAME was not declared. */ if (decl == error_mark_node) { if (parser->scope && parser->scope != global_namespace) error ("`%D::%D' has not been declared", parser->scope, name); else if (parser->scope == global_namespace) error ("`::%D' has not been declared", name); else error ("`%D' has not been declared", name); } else if (parser->scope && parser->scope != global_namespace) error ("`%D::%D' %s", parser->scope, name, desired); else if (parser->scope == global_namespace) error ("`::%D' %s", name, desired); else error ("`%D' %s", name, desired); } /* If we are parsing tentatively, remember that an error has occurred during this tentative parse. Returns true if the error was simulated; false if a messgae should be issued by the caller. */ static bool cp_parser_simulate_error (cp_parser* parser) { if (cp_parser_parsing_tentatively (parser) && !cp_parser_committed_to_tentative_parse (parser)) { parser->context->status = CP_PARSER_STATUS_KIND_ERROR; return true; } return false; } /* This function is called when a type is defined. If type definitions are forbidden at this point, an error message is issued. */ static void cp_parser_check_type_definition (cp_parser* parser) { /* If types are forbidden here, issue a message. */ if (parser->type_definition_forbidden_message) /* Use `%s' to print the string in case there are any escape characters in the message. */ error ("%s", parser->type_definition_forbidden_message); } /* This function is called when a declaration is parsed. If DECLARATOR is a function declarator and DECLARES_CLASS_OR_ENUM indicates that a type was defined in the decl-specifiers for DECL, then an error is issued. */ static void cp_parser_check_for_definition_in_return_type (tree declarator, int declares_class_or_enum) { /* [dcl.fct] forbids type definitions in return types. Unfortunately, it's not easy to know whether or not we are processing a return type until after the fact. */ while (declarator && (TREE_CODE (declarator) == INDIRECT_REF || TREE_CODE (declarator) == ADDR_EXPR)) declarator = TREE_OPERAND (declarator, 0); if (declarator && TREE_CODE (declarator) == CALL_EXPR && declares_class_or_enum & 2) error ("new types may not be defined in a return type"); } /* A type-specifier (TYPE) has been parsed which cannot be followed by "<" in any valid C++ program. If the next token is indeed "<", issue a message warning the user about what appears to be an invalid attempt to form a template-id. */ static void cp_parser_check_for_invalid_template_id (cp_parser* parser, tree type) { ptrdiff_t start; cp_token *token; if (cp_lexer_next_token_is (parser->lexer, CPP_LESS)) { if (TYPE_P (type)) error ("`%T' is not a template", type); else if (TREE_CODE (type) == IDENTIFIER_NODE) error ("`%s' is not a template", IDENTIFIER_POINTER (type)); else error ("invalid template-id"); /* Remember the location of the invalid "<". */ if (cp_parser_parsing_tentatively (parser) && !cp_parser_committed_to_tentative_parse (parser)) { token = cp_lexer_peek_token (parser->lexer); token = cp_lexer_prev_token (parser->lexer, token); start = cp_lexer_token_difference (parser->lexer, parser->lexer->first_token, token); } else start = -1; /* Consume the "<". */ cp_lexer_consume_token (parser->lexer); /* Parse the template arguments. */ cp_parser_enclosed_template_argument_list (parser); /* Permanently remove the invalid template arguments so that this error message is not issued again. */ if (start >= 0) { token = cp_lexer_advance_token (parser->lexer, parser->lexer->first_token, start); cp_lexer_purge_tokens_after (parser->lexer, token); } } } /* If parsing an integral constant-expression, issue an error message about the fact that THING appeared and return true. Otherwise, return false, marking the current expression as non-constant. */ static bool cp_parser_non_integral_constant_expression (cp_parser *parser, const char *thing) { if (parser->integral_constant_expression_p) { if (!parser->allow_non_integral_constant_expression_p) { error ("%s cannot appear in a constant-expression", thing); return true; } parser->non_integral_constant_expression_p = true; } return false; } /* Check for a common situation where a type-name should be present, but is not, and issue a sensible error message. Returns true if an invalid type-name was detected. */ static bool cp_parser_diagnose_invalid_type_name (cp_parser *parser) { /* If the next two tokens are both identifiers, the code is erroneous. The usual cause of this situation is code like: T t; where "T" should name a type -- but does not. */ if (cp_lexer_next_token_is (parser->lexer, CPP_NAME) && cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_NAME) { tree name; /* If parsing tentatively, we should commit; we really are looking at a declaration. */ /* Consume the first identifier. */ name = cp_lexer_consume_token (parser->lexer)->value; /* Issue an error message. */ error ("`%s' does not name a type", IDENTIFIER_POINTER (name)); /* If we're in a template class, it's possible that the user was referring to a type from a base class. For example: template struct A { typedef T X; }; template struct B : public A { X x; }; The user should have said "typename A::X". */ if (processing_template_decl && current_class_type) { tree b; for (b = TREE_CHAIN (TYPE_BINFO (current_class_type)); b; b = TREE_CHAIN (b)) { tree base_type = BINFO_TYPE (b); if (CLASS_TYPE_P (base_type) && dependent_type_p (base_type)) { tree field; /* Go from a particular instantiation of the template (which will have an empty TYPE_FIELDs), to the main version. */ base_type = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (base_type); for (field = TYPE_FIELDS (base_type); field; field = TREE_CHAIN (field)) if (TREE_CODE (field) == TYPE_DECL && DECL_NAME (field) == name) { error ("(perhaps `typename %T::%s' was intended)", BINFO_TYPE (b), IDENTIFIER_POINTER (name)); break; } if (field) break; } } } /* Skip to the end of the declaration; there's no point in trying to process it. */ cp_parser_skip_to_end_of_statement (parser); return true; } return false; } /* Consume tokens up to, and including, the next non-nested closing `)'. Returns 1 iff we found a closing `)'. RECOVERING is true, if we are doing error recovery. Returns -1 if OR_COMMA is true and we found an unnested comma. */ static int cp_parser_skip_to_closing_parenthesis (cp_parser *parser, bool recovering, bool or_comma, bool consume_paren) { unsigned paren_depth = 0; unsigned brace_depth = 0; if (recovering && !or_comma && cp_parser_parsing_tentatively (parser) && !cp_parser_committed_to_tentative_parse (parser)) return 0; while (true) { cp_token *token; /* If we've run out of tokens, then there is no closing `)'. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EOF)) return 0; token = cp_lexer_peek_token (parser->lexer); /* This matches the processing in skip_to_end_of_statement. */ if (token->type == CPP_SEMICOLON && !brace_depth) return 0; if (token->type == CPP_OPEN_BRACE) ++brace_depth; if (token->type == CPP_CLOSE_BRACE) { if (!brace_depth--) return 0; } if (recovering && or_comma && token->type == CPP_COMMA && !brace_depth && !paren_depth) return -1; if (!brace_depth) { /* If it is an `(', we have entered another level of nesting. */ if (token->type == CPP_OPEN_PAREN) ++paren_depth; /* If it is a `)', then we might be done. */ else if (token->type == CPP_CLOSE_PAREN && !paren_depth--) { if (consume_paren) cp_lexer_consume_token (parser->lexer); return 1; } } /* Consume the token. */ cp_lexer_consume_token (parser->lexer); } } /* Consume tokens until we reach the end of the current statement. Normally, that will be just before consuming a `;'. However, if a non-nested `}' comes first, then we stop before consuming that. */ static void cp_parser_skip_to_end_of_statement (cp_parser* parser) { unsigned nesting_depth = 0; while (true) { cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If we've run out of tokens, stop. */ if (token->type == CPP_EOF) break; /* If the next token is a `;', we have reached the end of the statement. */ if (token->type == CPP_SEMICOLON && !nesting_depth) break; /* If the next token is a non-nested `}', then we have reached the end of the current block. */ if (token->type == CPP_CLOSE_BRACE) { /* If this is a non-nested `}', stop before consuming it. That way, when confronted with something like: { 3 + } we stop before consuming the closing `}', even though we have not yet reached a `;'. */ if (nesting_depth == 0) break; /* If it is the closing `}' for a block that we have scanned, stop -- but only after consuming the token. That way given: void f g () { ... } typedef int I; we will stop after the body of the erroneously declared function, but before consuming the following `typedef' declaration. */ if (--nesting_depth == 0) { cp_lexer_consume_token (parser->lexer); break; } } /* If it the next token is a `{', then we are entering a new block. Consume the entire block. */ else if (token->type == CPP_OPEN_BRACE) ++nesting_depth; /* Consume the token. */ cp_lexer_consume_token (parser->lexer); } } /* This function is called at the end of a statement or declaration. If the next token is a semicolon, it is consumed; otherwise, error recovery is attempted. */ static void cp_parser_consume_semicolon_at_end_of_statement (cp_parser *parser) { /* Look for the trailing `;'. */ if (!cp_parser_require (parser, CPP_SEMICOLON, "`;'")) { /* If there is additional (erroneous) input, skip to the end of the statement. */ cp_parser_skip_to_end_of_statement (parser); /* If the next token is now a `;', consume it. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON)) cp_lexer_consume_token (parser->lexer); } } /* Skip tokens until we have consumed an entire block, or until we have consumed a non-nested `;'. */ static void cp_parser_skip_to_end_of_block_or_statement (cp_parser* parser) { unsigned nesting_depth = 0; while (true) { cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If we've run out of tokens, stop. */ if (token->type == CPP_EOF) break; /* If the next token is a `;', we have reached the end of the statement. */ if (token->type == CPP_SEMICOLON && !nesting_depth) { /* Consume the `;'. */ cp_lexer_consume_token (parser->lexer); break; } /* Consume the token. */ token = cp_lexer_consume_token (parser->lexer); /* If the next token is a non-nested `}', then we have reached the end of the current block. */ if (token->type == CPP_CLOSE_BRACE && (nesting_depth == 0 || --nesting_depth == 0)) break; /* If it the next token is a `{', then we are entering a new block. Consume the entire block. */ if (token->type == CPP_OPEN_BRACE) ++nesting_depth; } } /* Skip tokens until a non-nested closing curly brace is the next token. */ static void cp_parser_skip_to_closing_brace (cp_parser *parser) { unsigned nesting_depth = 0; while (true) { cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If we've run out of tokens, stop. */ if (token->type == CPP_EOF) break; /* If the next token is a non-nested `}', then we have reached the end of the current block. */ if (token->type == CPP_CLOSE_BRACE && nesting_depth-- == 0) break; /* If it the next token is a `{', then we are entering a new block. Consume the entire block. */ else if (token->type == CPP_OPEN_BRACE) ++nesting_depth; /* Consume the token. */ cp_lexer_consume_token (parser->lexer); } } /* Create a new C++ parser. */ static cp_parser * cp_parser_new (void) { cp_parser *parser; cp_lexer *lexer; /* cp_lexer_new_main is called before calling ggc_alloc because cp_lexer_new_main might load a PCH file. */ lexer = cp_lexer_new_main (); parser = ggc_alloc_cleared (sizeof (cp_parser)); parser->lexer = lexer; parser->context = cp_parser_context_new (NULL); /* For now, we always accept GNU extensions. */ parser->allow_gnu_extensions_p = 1; /* The `>' token is a greater-than operator, not the end of a template-id. */ parser->greater_than_is_operator_p = true; parser->default_arg_ok_p = true; /* We are not parsing a constant-expression. */ parser->integral_constant_expression_p = false; parser->allow_non_integral_constant_expression_p = false; parser->non_integral_constant_expression_p = false; /* We are not parsing offsetof. */ parser->in_offsetof_p = false; /* Local variable names are not forbidden. */ parser->local_variables_forbidden_p = false; /* We are not processing an `extern "C"' declaration. */ parser->in_unbraced_linkage_specification_p = false; /* We are not processing a declarator. */ parser->in_declarator_p = false; /* We are not processing a template-argument-list. */ parser->in_template_argument_list_p = false; /* We are not in an iteration statement. */ parser->in_iteration_statement_p = false; /* We are not in a switch statement. */ parser->in_switch_statement_p = false; /* We are not parsing a type-id inside an expression. */ parser->in_type_id_in_expr_p = false; /* The unparsed function queue is empty. */ parser->unparsed_functions_queues = build_tree_list (NULL_TREE, NULL_TREE); /* There are no classes being defined. */ parser->num_classes_being_defined = 0; /* No template parameters apply. */ parser->num_template_parameter_lists = 0; return parser; } /* Lexical conventions [gram.lex] */ /* Parse an identifier. Returns an IDENTIFIER_NODE representing the identifier. */ static tree cp_parser_identifier (cp_parser* parser) { cp_token *token; /* Look for the identifier. */ token = cp_parser_require (parser, CPP_NAME, "identifier"); /* Return the value. */ return token ? token->value : error_mark_node; } /* Basic concepts [gram.basic] */ /* Parse a translation-unit. translation-unit: declaration-seq [opt] Returns TRUE if all went well. */ static bool cp_parser_translation_unit (cp_parser* parser) { while (true) { cp_parser_declaration_seq_opt (parser); /* If there are no tokens left then all went well. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EOF)) break; /* Otherwise, issue an error message. */ cp_parser_error (parser, "expected declaration"); return false; } /* Consume the EOF token. */ cp_parser_require (parser, CPP_EOF, "end-of-file"); /* Finish up. */ finish_translation_unit (); /* All went well. */ return true; } /* Expressions [gram.expr] */ /* Parse a primary-expression. primary-expression: literal this ( expression ) id-expression GNU Extensions: primary-expression: ( compound-statement ) __builtin_va_arg ( assignment-expression , type-id ) literal: __null Returns a representation of the expression. *IDK indicates what kind of id-expression (if any) was present. *QUALIFYING_CLASS is set to a non-NULL value if the id-expression can be used as the operand of a pointer-to-member. In that case, *QUALIFYING_CLASS gives the class that is used as the qualifying class in the pointer-to-member. */ static tree cp_parser_primary_expression (cp_parser *parser, cp_id_kind *idk, tree *qualifying_class) { cp_token *token; /* Assume the primary expression is not an id-expression. */ *idk = CP_ID_KIND_NONE; /* And that it cannot be used as pointer-to-member. */ *qualifying_class = NULL_TREE; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); switch (token->type) { /* literal: integer-literal character-literal floating-literal string-literal boolean-literal */ case CPP_CHAR: case CPP_WCHAR: case CPP_STRING: case CPP_WSTRING: case CPP_NUMBER: token = cp_lexer_consume_token (parser->lexer); return token->value; case CPP_OPEN_PAREN: { tree expr; bool saved_greater_than_is_operator_p; /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* Within a parenthesized expression, a `>' token is always the greater-than operator. */ saved_greater_than_is_operator_p = parser->greater_than_is_operator_p; parser->greater_than_is_operator_p = true; /* If we see `( { ' then we are looking at the beginning of a GNU statement-expression. */ if (cp_parser_allow_gnu_extensions_p (parser) && cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE)) { /* Statement-expressions are not allowed by the standard. */ if (pedantic) pedwarn ("ISO C++ forbids braced-groups within expressions"); /* And they're not allowed outside of a function-body; you cannot, for example, write: int i = ({ int j = 3; j + 1; }); at class or namespace scope. */ if (!at_function_scope_p ()) error ("statement-expressions are allowed only inside functions"); /* Start the statement-expression. */ expr = begin_stmt_expr (); /* Parse the compound-statement. */ cp_parser_compound_statement (parser, true); /* Finish up. */ expr = finish_stmt_expr (expr, false); } else { /* Parse the parenthesized expression. */ expr = cp_parser_expression (parser); /* Let the front end know that this expression was enclosed in parentheses. This matters in case, for example, the expression is of the form `A::B', since `&A::B' might be a pointer-to-member, but `&(A::B)' is not. */ finish_parenthesized_expr (expr); } /* The `>' token might be the end of a template-id or template-parameter-list now. */ parser->greater_than_is_operator_p = saved_greater_than_is_operator_p; /* Consume the `)'. */ if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) cp_parser_skip_to_end_of_statement (parser); return expr; } case CPP_KEYWORD: switch (token->keyword) { /* These two are the boolean literals. */ case RID_TRUE: cp_lexer_consume_token (parser->lexer); return boolean_true_node; case RID_FALSE: cp_lexer_consume_token (parser->lexer); return boolean_false_node; /* The `__null' literal. */ case RID_NULL: cp_lexer_consume_token (parser->lexer); return null_node; /* Recognize the `this' keyword. */ case RID_THIS: cp_lexer_consume_token (parser->lexer); if (parser->local_variables_forbidden_p) { error ("`this' may not be used in this context"); return error_mark_node; } /* Pointers cannot appear in constant-expressions. */ if (cp_parser_non_integral_constant_expression (parser, "`this'")) return error_mark_node; return finish_this_expr (); /* The `operator' keyword can be the beginning of an id-expression. */ case RID_OPERATOR: goto id_expression; case RID_FUNCTION_NAME: case RID_PRETTY_FUNCTION_NAME: case RID_C99_FUNCTION_NAME: /* The symbols __FUNCTION__, __PRETTY_FUNCTION__, and __func__ are the names of variables -- but they are treated specially. Therefore, they are handled here, rather than relying on the generic id-expression logic below. Grammatically, these names are id-expressions. Consume the token. */ token = cp_lexer_consume_token (parser->lexer); /* Look up the name. */ return finish_fname (token->value); case RID_VA_ARG: { tree expression; tree type; /* The `__builtin_va_arg' construct is used to handle `va_arg'. Consume the `__builtin_va_arg' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the opening `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Now, parse the assignment-expression. */ expression = cp_parser_assignment_expression (parser); /* Look for the `,'. */ cp_parser_require (parser, CPP_COMMA, "`,'"); /* Parse the type-id. */ type = cp_parser_type_id (parser); /* Look for the closing `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Using `va_arg' in a constant-expression is not allowed. */ if (cp_parser_non_integral_constant_expression (parser, "`va_arg'")) return error_mark_node; return build_x_va_arg (expression, type); } case RID_OFFSETOF: { tree expression; bool saved_in_offsetof_p; /* Consume the "__offsetof__" token. */ cp_lexer_consume_token (parser->lexer); /* Consume the opening `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Parse the parenthesized (almost) constant-expression. */ saved_in_offsetof_p = parser->in_offsetof_p; parser->in_offsetof_p = true; expression = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/false, /*non_constant_p=*/NULL); parser->in_offsetof_p = saved_in_offsetof_p; /* Consume the closing ')'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); return expression; } default: cp_parser_error (parser, "expected primary-expression"); return error_mark_node; } /* An id-expression can start with either an identifier, a `::' as the beginning of a qualified-id, or the "operator" keyword. */ case CPP_NAME: case CPP_SCOPE: case CPP_TEMPLATE_ID: case CPP_NESTED_NAME_SPECIFIER: { tree id_expression; tree decl; const char *error_msg; id_expression: /* Parse the id-expression. */ id_expression = cp_parser_id_expression (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, /*template_p=*/NULL, /*declarator_p=*/false); if (id_expression == error_mark_node) return error_mark_node; /* If we have a template-id, then no further lookup is required. If the template-id was for a template-class, we will sometimes have a TYPE_DECL at this point. */ else if (TREE_CODE (id_expression) == TEMPLATE_ID_EXPR || TREE_CODE (id_expression) == TYPE_DECL) decl = id_expression; /* Look up the name. */ else { decl = cp_parser_lookup_name_simple (parser, id_expression); /* If name lookup gives us a SCOPE_REF, then the qualifying scope was dependent. Just propagate the name. */ if (TREE_CODE (decl) == SCOPE_REF) { if (TYPE_P (TREE_OPERAND (decl, 0))) *qualifying_class = TREE_OPERAND (decl, 0); return decl; } /* Check to see if DECL is a local variable in a context where that is forbidden. */ if (parser->local_variables_forbidden_p && local_variable_p (decl)) { /* It might be that we only found DECL because we are trying to be generous with pre-ISO scoping rules. For example, consider: int i; void g() { for (int i = 0; i < 10; ++i) {} extern void f(int j = i); } Here, name look up will originally find the out of scope `i'. We need to issue a warning message, but then use the global `i'. */ decl = check_for_out_of_scope_variable (decl); if (local_variable_p (decl)) { error ("local variable `%D' may not appear in this context", decl); return error_mark_node; } } } decl = finish_id_expression (id_expression, decl, parser->scope, idk, qualifying_class, parser->integral_constant_expression_p, parser->allow_non_integral_constant_expression_p, &parser->non_integral_constant_expression_p, &error_msg); if (error_msg) cp_parser_error (parser, error_msg); return decl; } /* Anything else is an error. */ default: cp_parser_error (parser, "expected primary-expression"); return error_mark_node; } } /* Parse an id-expression. id-expression: unqualified-id qualified-id qualified-id: :: [opt] nested-name-specifier template [opt] unqualified-id :: identifier :: operator-function-id :: template-id Return a representation of the unqualified portion of the identifier. Sets PARSER->SCOPE to the qualifying scope if there is a `::' or nested-name-specifier. Often, if the id-expression was a qualified-id, the caller will want to make a SCOPE_REF to represent the qualified-id. This function does not do this in order to avoid wastefully creating SCOPE_REFs when they are not required. If TEMPLATE_KEYWORD_P is true, then we have just seen the `template' keyword. If CHECK_DEPENDENCY_P is false, then names are looked up inside uninstantiated templates. If *TEMPLATE_P is non-NULL, it is set to true iff the `template' keyword is used to explicitly indicate that the entity named is a template. If DECLARATOR_P is true, the id-expression is appearing as part of a declarator, rather than as part of an expression. */ static tree cp_parser_id_expression (cp_parser *parser, bool template_keyword_p, bool check_dependency_p, bool *template_p, bool declarator_p) { bool global_scope_p; bool nested_name_specifier_p; /* Assume the `template' keyword was not used. */ if (template_p) *template_p = false; /* Look for the optional `::' operator. */ global_scope_p = (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false) != NULL_TREE); /* Look for the optional nested-name-specifier. */ nested_name_specifier_p = (cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, check_dependency_p, /*type_p=*/false, /*is_declarator=*/false) != NULL_TREE); /* If there is a nested-name-specifier, then we are looking at the first qualified-id production. */ if (nested_name_specifier_p) { tree saved_scope; tree saved_object_scope; tree saved_qualifying_scope; tree unqualified_id; bool is_template; /* See if the next token is the `template' keyword. */ if (!template_p) template_p = &is_template; *template_p = cp_parser_optional_template_keyword (parser); /* Name lookup we do during the processing of the unqualified-id might obliterate SCOPE. */ saved_scope = parser->scope; saved_object_scope = parser->object_scope; saved_qualifying_scope = parser->qualifying_scope; /* Process the final unqualified-id. */ unqualified_id = cp_parser_unqualified_id (parser, *template_p, check_dependency_p, declarator_p); /* Restore the SAVED_SCOPE for our caller. */ parser->scope = saved_scope; parser->object_scope = saved_object_scope; parser->qualifying_scope = saved_qualifying_scope; return unqualified_id; } /* Otherwise, if we are in global scope, then we are looking at one of the other qualified-id productions. */ else if (global_scope_p) { cp_token *token; tree id; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's an identifier, and the next token is not a "<", then we can avoid the template-id case. This is an optimization for this common case. */ if (token->type == CPP_NAME && !cp_parser_nth_token_starts_template_argument_list_p (parser, 2)) return cp_parser_identifier (parser); cp_parser_parse_tentatively (parser); /* Try a template-id. */ id = cp_parser_template_id (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, declarator_p); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) return id; /* Peek at the next token. (Changes in the token buffer may have invalidated the pointer obtained above.) */ token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_NAME: return cp_parser_identifier (parser); case CPP_KEYWORD: if (token->keyword == RID_OPERATOR) return cp_parser_operator_function_id (parser); /* Fall through. */ default: cp_parser_error (parser, "expected id-expression"); return error_mark_node; } } else return cp_parser_unqualified_id (parser, template_keyword_p, /*check_dependency_p=*/true, declarator_p); } /* Parse an unqualified-id. unqualified-id: identifier operator-function-id conversion-function-id ~ class-name template-id If TEMPLATE_KEYWORD_P is TRUE, we have just seen the `template' keyword, in a construct like `A::template ...'. Returns a representation of unqualified-id. For the `identifier' production, an IDENTIFIER_NODE is returned. For the `~ class-name' production a BIT_NOT_EXPR is returned; the operand of the BIT_NOT_EXPR is an IDENTIFIER_NODE for the class-name. For the other productions, see the documentation accompanying the corresponding parsing functions. If CHECK_DEPENDENCY_P is false, names are looked up in uninstantiated templates. If DECLARATOR_P is true, the unqualified-id is appearing as part of a declarator, rather than as part of an expression. */ static tree cp_parser_unqualified_id (cp_parser* parser, bool template_keyword_p, bool check_dependency_p, bool declarator_p) { cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_NAME: { tree id; /* We don't know yet whether or not this will be a template-id. */ cp_parser_parse_tentatively (parser); /* Try a template-id. */ id = cp_parser_template_id (parser, template_keyword_p, check_dependency_p, declarator_p); /* If it worked, we're done. */ if (cp_parser_parse_definitely (parser)) return id; /* Otherwise, it's an ordinary identifier. */ return cp_parser_identifier (parser); } case CPP_TEMPLATE_ID: return cp_parser_template_id (parser, template_keyword_p, check_dependency_p, declarator_p); case CPP_COMPL: { tree type_decl; tree qualifying_scope; tree object_scope; tree scope; /* Consume the `~' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the class-name. The standard, as written, seems to say that: template struct S { ~S (); }; template S::~S() {} is invalid, since `~' must be followed by a class-name, but `S' is dependent, and so not known to be a class. That's not right; we need to look in uninstantiated templates. A further complication arises from: template void f(T t) { t.T::~T(); } Here, it is not possible to look up `T' in the scope of `T' itself. We must look in both the current scope, and the scope of the containing complete expression. Yet another issue is: struct S { int S; ~S(); }; S::~S() {} The standard does not seem to say that the `S' in `~S' should refer to the type `S' and not the data member `S::S'. */ /* DR 244 says that we look up the name after the "~" in the same scope as we looked up the qualifying name. That idea isn't fully worked out; it's more complicated than that. */ scope = parser->scope; object_scope = parser->object_scope; qualifying_scope = parser->qualifying_scope; /* If the name is of the form "X::~X" it's OK. */ if (scope && TYPE_P (scope) && cp_lexer_next_token_is (parser->lexer, CPP_NAME) && (cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_OPEN_PAREN) && (cp_lexer_peek_token (parser->lexer)->value == TYPE_IDENTIFIER (scope))) { cp_lexer_consume_token (parser->lexer); return build_nt (BIT_NOT_EXPR, scope); } /* If there was an explicit qualification (S::~T), first look in the scope given by the qualification (i.e., S). */ if (scope) { cp_parser_parse_tentatively (parser); type_decl = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, /*type_p=*/false, /*check_dependency=*/false, /*class_head_p=*/false, declarator_p); if (cp_parser_parse_definitely (parser)) return build_nt (BIT_NOT_EXPR, TREE_TYPE (type_decl)); } /* In "N::S::~S", look in "N" as well. */ if (scope && qualifying_scope) { cp_parser_parse_tentatively (parser); parser->scope = qualifying_scope; parser->object_scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; type_decl = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, /*type_p=*/false, /*check_dependency=*/false, /*class_head_p=*/false, declarator_p); if (cp_parser_parse_definitely (parser)) return build_nt (BIT_NOT_EXPR, TREE_TYPE (type_decl)); } /* In "p->S::~T", look in the scope given by "*p" as well. */ else if (object_scope) { cp_parser_parse_tentatively (parser); parser->scope = object_scope; parser->object_scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; type_decl = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, /*type_p=*/false, /*check_dependency=*/false, /*class_head_p=*/false, declarator_p); if (cp_parser_parse_definitely (parser)) return build_nt (BIT_NOT_EXPR, TREE_TYPE (type_decl)); } /* Look in the surrounding context. */ parser->scope = NULL_TREE; parser->object_scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; type_decl = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, /*type_p=*/false, /*check_dependency=*/false, /*class_head_p=*/false, declarator_p); /* If an error occurred, assume that the name of the destructor is the same as the name of the qualifying class. That allows us to keep parsing after running into ill-formed destructor names. */ if (type_decl == error_mark_node && scope && TYPE_P (scope)) return build_nt (BIT_NOT_EXPR, scope); else if (type_decl == error_mark_node) return error_mark_node; /* [class.dtor] A typedef-name that names a class shall not be used as the identifier in the declarator for a destructor declaration. */ if (declarator_p && !DECL_IMPLICIT_TYPEDEF_P (type_decl) && !DECL_SELF_REFERENCE_P (type_decl)) error ("typedef-name `%D' used as destructor declarator", type_decl); return build_nt (BIT_NOT_EXPR, TREE_TYPE (type_decl)); } case CPP_KEYWORD: if (token->keyword == RID_OPERATOR) { tree id; /* This could be a template-id, so we try that first. */ cp_parser_parse_tentatively (parser); /* Try a template-id. */ id = cp_parser_template_id (parser, template_keyword_p, /*check_dependency_p=*/true, declarator_p); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) return id; /* We still don't know whether we're looking at an operator-function-id or a conversion-function-id. */ cp_parser_parse_tentatively (parser); /* Try an operator-function-id. */ id = cp_parser_operator_function_id (parser); /* If that didn't work, try a conversion-function-id. */ if (!cp_parser_parse_definitely (parser)) id = cp_parser_conversion_function_id (parser); return id; } /* Fall through. */ default: cp_parser_error (parser, "expected unqualified-id"); return error_mark_node; } } /* Parse an (optional) nested-name-specifier. nested-name-specifier: class-or-namespace-name :: nested-name-specifier [opt] class-or-namespace-name :: template nested-name-specifier [opt] PARSER->SCOPE should be set appropriately before this function is called. TYPENAME_KEYWORD_P is TRUE if the `typename' keyword is in effect. TYPE_P is TRUE if we non-type bindings should be ignored in name lookups. Sets PARSER->SCOPE to the class (TYPE) or namespace (NAMESPACE_DECL) specified by the nested-name-specifier, or leaves it unchanged if there is no nested-name-specifier. Returns the new scope iff there is a nested-name-specifier, or NULL_TREE otherwise. If IS_DECLARATION is TRUE, the nested-name-specifier is known to be part of a declaration and/or decl-specifier. */ static tree cp_parser_nested_name_specifier_opt (cp_parser *parser, bool typename_keyword_p, bool check_dependency_p, bool type_p, bool is_declaration) { bool success = false; tree access_check = NULL_TREE; ptrdiff_t start; cp_token* token; /* If the next token corresponds to a nested name specifier, there is no need to reparse it. However, if CHECK_DEPENDENCY_P is false, it may have been true before, in which case something like `A::B::C' may have resulted in a nested-name-specifier of `A::', where it should now be `A::B::'. So, when CHECK_DEPENDENCY_P is false, we have to fall through into the main loop. */ if (check_dependency_p && cp_lexer_next_token_is (parser->lexer, CPP_NESTED_NAME_SPECIFIER)) { cp_parser_pre_parsed_nested_name_specifier (parser); return parser->scope; } /* Remember where the nested-name-specifier starts. */ if (cp_parser_parsing_tentatively (parser) && !cp_parser_committed_to_tentative_parse (parser)) { token = cp_lexer_peek_token (parser->lexer); start = cp_lexer_token_difference (parser->lexer, parser->lexer->first_token, token); } else start = -1; push_deferring_access_checks (dk_deferred); while (true) { tree new_scope; tree old_scope; tree saved_qualifying_scope; bool template_keyword_p; /* Spot cases that cannot be the beginning of a nested-name-specifier. */ token = cp_lexer_peek_token (parser->lexer); /* If the next token is CPP_NESTED_NAME_SPECIFIER, just process the already parsed nested-name-specifier. */ if (token->type == CPP_NESTED_NAME_SPECIFIER) { /* Grab the nested-name-specifier and continue the loop. */ cp_parser_pre_parsed_nested_name_specifier (parser); success = true; continue; } /* Spot cases that cannot be the beginning of a nested-name-specifier. On the second and subsequent times through the loop, we look for the `template' keyword. */ if (success && token->keyword == RID_TEMPLATE) ; /* A template-id can start a nested-name-specifier. */ else if (token->type == CPP_TEMPLATE_ID) ; else { /* If the next token is not an identifier, then it is definitely not a class-or-namespace-name. */ if (token->type != CPP_NAME) break; /* If the following token is neither a `<' (to begin a template-id), nor a `::', then we are not looking at a nested-name-specifier. */ token = cp_lexer_peek_nth_token (parser->lexer, 2); if (token->type != CPP_SCOPE && !cp_parser_nth_token_starts_template_argument_list_p (parser, 2)) break; } /* The nested-name-specifier is optional, so we parse tentatively. */ cp_parser_parse_tentatively (parser); /* Look for the optional `template' keyword, if this isn't the first time through the loop. */ if (success) template_keyword_p = cp_parser_optional_template_keyword (parser); else template_keyword_p = false; /* Save the old scope since the name lookup we are about to do might destroy it. */ old_scope = parser->scope; saved_qualifying_scope = parser->qualifying_scope; /* Parse the qualifying entity. */ new_scope = cp_parser_class_or_namespace_name (parser, typename_keyword_p, template_keyword_p, check_dependency_p, type_p, is_declaration); /* Look for the `::' token. */ cp_parser_require (parser, CPP_SCOPE, "`::'"); /* If we found what we wanted, we keep going; otherwise, we're done. */ if (!cp_parser_parse_definitely (parser)) { bool error_p = false; /* Restore the OLD_SCOPE since it was valid before the failed attempt at finding the last class-or-namespace-name. */ parser->scope = old_scope; parser->qualifying_scope = saved_qualifying_scope; /* If the next token is an identifier, and the one after that is a `::', then any valid interpretation would have found a class-or-namespace-name. */ while (cp_lexer_next_token_is (parser->lexer, CPP_NAME) && (cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_SCOPE) && (cp_lexer_peek_nth_token (parser->lexer, 3)->type != CPP_COMPL)) { token = cp_lexer_consume_token (parser->lexer); if (!error_p) { tree decl; decl = cp_parser_lookup_name_simple (parser, token->value); if (TREE_CODE (decl) == TEMPLATE_DECL) error ("`%D' used without template parameters", decl); else cp_parser_name_lookup_error (parser, token->value, decl, "is not a class or namespace"); parser->scope = NULL_TREE; error_p = true; /* Treat this as a successful nested-name-specifier due to: [basic.lookup.qual] If the name found is not a class-name (clause _class_) or namespace-name (_namespace.def_), the program is ill-formed. */ success = true; } cp_lexer_consume_token (parser->lexer); } break; } /* We've found one valid nested-name-specifier. */ success = true; /* Make sure we look in the right scope the next time through the loop. */ parser->scope = (TREE_CODE (new_scope) == TYPE_DECL ? TREE_TYPE (new_scope) : new_scope); /* If it is a class scope, try to complete it; we are about to be looking up names inside the class. */ if (TYPE_P (parser->scope) /* Since checking types for dependency can be expensive, avoid doing it if the type is already complete. */ && !COMPLETE_TYPE_P (parser->scope) /* Do not try to complete dependent types. */ && !dependent_type_p (parser->scope)) complete_type (parser->scope); } /* Retrieve any deferred checks. Do not pop this access checks yet so the memory will not be reclaimed during token replacing below. */ access_check = get_deferred_access_checks (); /* If parsing tentatively, replace the sequence of tokens that makes up the nested-name-specifier with a CPP_NESTED_NAME_SPECIFIER token. That way, should we re-parse the token stream, we will not have to repeat the effort required to do the parse, nor will we issue duplicate error messages. */ if (success && start >= 0) { /* Find the token that corresponds to the start of the template-id. */ token = cp_lexer_advance_token (parser->lexer, parser->lexer->first_token, start); /* Reset the contents of the START token. */ token->type = CPP_NESTED_NAME_SPECIFIER; token->value = build_tree_list (access_check, parser->scope); TREE_TYPE (token->value) = parser->qualifying_scope; token->keyword = RID_MAX; /* Purge all subsequent tokens. */ cp_lexer_purge_tokens_after (parser->lexer, token); } pop_deferring_access_checks (); return success ? parser->scope : NULL_TREE; } /* Parse a nested-name-specifier. See cp_parser_nested_name_specifier_opt for details. This function behaves identically, except that it will an issue an error if no nested-name-specifier is present, and it will return ERROR_MARK_NODE, rather than NULL_TREE, if no nested-name-specifier is present. */ static tree cp_parser_nested_name_specifier (cp_parser *parser, bool typename_keyword_p, bool check_dependency_p, bool type_p, bool is_declaration) { tree scope; /* Look for the nested-name-specifier. */ scope = cp_parser_nested_name_specifier_opt (parser, typename_keyword_p, check_dependency_p, type_p, is_declaration); /* If it was not present, issue an error message. */ if (!scope) { cp_parser_error (parser, "expected nested-name-specifier"); parser->scope = NULL_TREE; return error_mark_node; } return scope; } /* Parse a class-or-namespace-name. class-or-namespace-name: class-name namespace-name TYPENAME_KEYWORD_P is TRUE iff the `typename' keyword is in effect. TEMPLATE_KEYWORD_P is TRUE iff the `template' keyword is in effect. CHECK_DEPENDENCY_P is FALSE iff dependent names should be looked up. TYPE_P is TRUE iff the next name should be taken as a class-name, even the same name is declared to be another entity in the same scope. Returns the class (TYPE_DECL) or namespace (NAMESPACE_DECL) specified by the class-or-namespace-name. If neither is found the ERROR_MARK_NODE is returned. */ static tree cp_parser_class_or_namespace_name (cp_parser *parser, bool typename_keyword_p, bool template_keyword_p, bool check_dependency_p, bool type_p, bool is_declaration) { tree saved_scope; tree saved_qualifying_scope; tree saved_object_scope; tree scope; bool only_class_p; /* Before we try to parse the class-name, we must save away the current PARSER->SCOPE since cp_parser_class_name will destroy it. */ saved_scope = parser->scope; saved_qualifying_scope = parser->qualifying_scope; saved_object_scope = parser->object_scope; /* Try for a class-name first. If the SAVED_SCOPE is a type, then there is no need to look for a namespace-name. */ only_class_p = template_keyword_p || (saved_scope && TYPE_P (saved_scope)); if (!only_class_p) cp_parser_parse_tentatively (parser); scope = cp_parser_class_name (parser, typename_keyword_p, template_keyword_p, type_p, check_dependency_p, /*class_head_p=*/false, is_declaration); /* If that didn't work, try for a namespace-name. */ if (!only_class_p && !cp_parser_parse_definitely (parser)) { /* Restore the saved scope. */ parser->scope = saved_scope; parser->qualifying_scope = saved_qualifying_scope; parser->object_scope = saved_object_scope; /* If we are not looking at an identifier followed by the scope resolution operator, then this is not part of a nested-name-specifier. (Note that this function is only used to parse the components of a nested-name-specifier.) */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_NAME) || cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE) return error_mark_node; scope = cp_parser_namespace_name (parser); } return scope; } /* Parse a postfix-expression. postfix-expression: primary-expression postfix-expression [ expression ] postfix-expression ( expression-list [opt] ) simple-type-specifier ( expression-list [opt] ) typename :: [opt] nested-name-specifier identifier ( expression-list [opt] ) typename :: [opt] nested-name-specifier template [opt] template-id ( expression-list [opt] ) postfix-expression . template [opt] id-expression postfix-expression -> template [opt] id-expression postfix-expression . pseudo-destructor-name postfix-expression -> pseudo-destructor-name postfix-expression ++ postfix-expression -- dynamic_cast < type-id > ( expression ) static_cast < type-id > ( expression ) reinterpret_cast < type-id > ( expression ) const_cast < type-id > ( expression ) typeid ( expression ) typeid ( type-id ) GNU Extension: postfix-expression: ( type-id ) { initializer-list , [opt] } This extension is a GNU version of the C99 compound-literal construct. (The C99 grammar uses `type-name' instead of `type-id', but they are essentially the same concept.) If ADDRESS_P is true, the postfix expression is the operand of the `&' operator. Returns a representation of the expression. */ static tree cp_parser_postfix_expression (cp_parser *parser, bool address_p) { cp_token *token; enum rid keyword; cp_id_kind idk = CP_ID_KIND_NONE; tree postfix_expression = NULL_TREE; /* Non-NULL only if the current postfix-expression can be used to form a pointer-to-member. In that case, QUALIFYING_CLASS is the class used to qualify the member. */ tree qualifying_class = NULL_TREE; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Some of the productions are determined by keywords. */ keyword = token->keyword; switch (keyword) { case RID_DYNCAST: case RID_STATCAST: case RID_REINTCAST: case RID_CONSTCAST: { tree type; tree expression; const char *saved_message; /* All of these can be handled in the same way from the point of view of parsing. Begin by consuming the token identifying the cast. */ cp_lexer_consume_token (parser->lexer); /* New types cannot be defined in the cast. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in casts"; /* Look for the opening `<'. */ cp_parser_require (parser, CPP_LESS, "`<'"); /* Parse the type to which we are casting. */ type = cp_parser_type_id (parser); /* Look for the closing `>'. */ cp_parser_require (parser, CPP_GREATER, "`>'"); /* Restore the old message. */ parser->type_definition_forbidden_message = saved_message; /* And the expression which is being cast. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); expression = cp_parser_expression (parser); cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Only type conversions to integral or enumeration types can be used in constant-expressions. */ if (parser->integral_constant_expression_p && !dependent_type_p (type) && !INTEGRAL_OR_ENUMERATION_TYPE_P (type) /* A cast to pointer or reference type is allowed in the implementation of "offsetof". */ && !(parser->in_offsetof_p && POINTER_TYPE_P (type)) && (cp_parser_non_integral_constant_expression (parser, "a cast to a type other than an integral or " "enumeration type"))) return error_mark_node; switch (keyword) { case RID_DYNCAST: postfix_expression = build_dynamic_cast (type, expression); break; case RID_STATCAST: postfix_expression = build_static_cast (type, expression); break; case RID_REINTCAST: postfix_expression = build_reinterpret_cast (type, expression); break; case RID_CONSTCAST: postfix_expression = build_const_cast (type, expression); break; default: abort (); } } break; case RID_TYPEID: { tree type; const char *saved_message; bool saved_in_type_id_in_expr_p; /* Consume the `typeid' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the `(' token. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Types cannot be defined in a `typeid' expression. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in a `typeid\' expression"; /* We can't be sure yet whether we're looking at a type-id or an expression. */ cp_parser_parse_tentatively (parser); /* Try a type-id first. */ saved_in_type_id_in_expr_p = parser->in_type_id_in_expr_p; parser->in_type_id_in_expr_p = true; type = cp_parser_type_id (parser); parser->in_type_id_in_expr_p = saved_in_type_id_in_expr_p; /* Look for the `)' token. Otherwise, we can't be sure that we're not looking at an expression: consider `typeid (int (3))', for example. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* If all went well, simply lookup the type-id. */ if (cp_parser_parse_definitely (parser)) postfix_expression = get_typeid (type); /* Otherwise, fall back to the expression variant. */ else { tree expression; /* Look for an expression. */ expression = cp_parser_expression (parser); /* Compute its typeid. */ postfix_expression = build_typeid (expression); /* Look for the `)' token. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); } /* `typeid' may not appear in an integral constant expression. */ if (cp_parser_non_integral_constant_expression(parser, "`typeid' operator")) return error_mark_node; /* Restore the saved message. */ parser->type_definition_forbidden_message = saved_message; } break; case RID_TYPENAME: { bool template_p = false; tree id; tree type; /* Consume the `typename' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the optional `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* Look for the nested-name-specifier. */ cp_parser_nested_name_specifier (parser, /*typename_keyword_p=*/true, /*check_dependency_p=*/true, /*type_p=*/true, /*is_declaration=*/true); /* Look for the optional `template' keyword. */ template_p = cp_parser_optional_template_keyword (parser); /* We don't know whether we're looking at a template-id or an identifier. */ cp_parser_parse_tentatively (parser); /* Try a template-id. */ id = cp_parser_template_id (parser, template_p, /*check_dependency_p=*/true, /*is_declaration=*/true); /* If that didn't work, try an identifier. */ if (!cp_parser_parse_definitely (parser)) id = cp_parser_identifier (parser); /* If we look up a template-id in a non-dependent qualifying scope, there's no need to create a dependent type. */ if (TREE_CODE (id) == TYPE_DECL && !dependent_type_p (parser->scope)) type = TREE_TYPE (id); /* Create a TYPENAME_TYPE to represent the type to which the functional cast is being performed. */ else type = make_typename_type (parser->scope, id, /*complain=*/1); postfix_expression = cp_parser_functional_cast (parser, type); } break; default: { tree type; /* If the next thing is a simple-type-specifier, we may be looking at a functional cast. We could also be looking at an id-expression. So, we try the functional cast, and if that doesn't work we fall back to the primary-expression. */ cp_parser_parse_tentatively (parser); /* Look for the simple-type-specifier. */ type = cp_parser_simple_type_specifier (parser, CP_PARSER_FLAGS_NONE, /*identifier_p=*/false); /* Parse the cast itself. */ if (!cp_parser_error_occurred (parser)) postfix_expression = cp_parser_functional_cast (parser, type); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) break; /* If the functional-cast didn't work out, try a compound-literal. */ if (cp_parser_allow_gnu_extensions_p (parser) && cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN)) { tree initializer_list = NULL_TREE; bool saved_in_type_id_in_expr_p; cp_parser_parse_tentatively (parser); /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* Parse the type. */ saved_in_type_id_in_expr_p = parser->in_type_id_in_expr_p; parser->in_type_id_in_expr_p = true; type = cp_parser_type_id (parser); parser->in_type_id_in_expr_p = saved_in_type_id_in_expr_p; /* Look for the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Look for the `{'. */ cp_parser_require (parser, CPP_OPEN_BRACE, "`{'"); /* If things aren't going well, there's no need to keep going. */ if (!cp_parser_error_occurred (parser)) { bool non_constant_p; /* Parse the initializer-list. */ initializer_list = cp_parser_initializer_list (parser, &non_constant_p); /* Allow a trailing `,'. */ if (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)) cp_lexer_consume_token (parser->lexer); /* Look for the final `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); } /* If that worked, we're definitely looking at a compound-literal expression. */ if (cp_parser_parse_definitely (parser)) { /* Warn the user that a compound literal is not allowed in standard C++. */ if (pedantic) pedwarn ("ISO C++ forbids compound-literals"); /* Form the representation of the compound-literal. */ postfix_expression = finish_compound_literal (type, initializer_list); break; } } /* It must be a primary-expression. */ postfix_expression = cp_parser_primary_expression (parser, &idk, &qualifying_class); } break; } /* If we were avoiding committing to the processing of a qualified-id until we knew whether or not we had a pointer-to-member, we now know. */ if (qualifying_class) { bool done; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); done = (token->type != CPP_OPEN_SQUARE && token->type != CPP_OPEN_PAREN && token->type != CPP_DOT && token->type != CPP_DEREF && token->type != CPP_PLUS_PLUS && token->type != CPP_MINUS_MINUS); postfix_expression = finish_qualified_id_expr (qualifying_class, postfix_expression, done, address_p); if (done) return postfix_expression; } /* Keep looping until the postfix-expression is complete. */ while (true) { if (idk == CP_ID_KIND_UNQUALIFIED && TREE_CODE (postfix_expression) == IDENTIFIER_NODE && cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_PAREN)) /* It is not a Koenig lookup function call. */ postfix_expression = unqualified_name_lookup_error (postfix_expression); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_OPEN_SQUARE: /* postfix-expression [ expression ] */ { tree index; /* Consume the `[' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the index expression. */ index = cp_parser_expression (parser); /* Look for the closing `]'. */ cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'"); /* Build the ARRAY_REF. */ postfix_expression = grok_array_decl (postfix_expression, index); idk = CP_ID_KIND_NONE; /* Array references are not permitted in constant-expressions (but they are allowed in offsetof). */ if (!parser->in_offsetof_p && cp_parser_non_integral_constant_expression (parser, "an array reference")) postfix_expression = error_mark_node; } break; case CPP_OPEN_PAREN: /* postfix-expression ( expression-list [opt] ) */ { bool koenig_p; tree args = (cp_parser_parenthesized_expression_list (parser, false, /*non_constant_p=*/NULL)); if (args == error_mark_node) { postfix_expression = error_mark_node; break; } /* Function calls are not permitted in constant-expressions. */ if (cp_parser_non_integral_constant_expression (parser, "a function call")) { postfix_expression = error_mark_node; break; } koenig_p = false; if (idk == CP_ID_KIND_UNQUALIFIED) { /* We do not perform argument-dependent lookup if normal lookup finds a non-function, in accordance with the expected resolution of DR 218. */ if (args && (is_overloaded_fn (postfix_expression) || TREE_CODE (postfix_expression) == IDENTIFIER_NODE)) { koenig_p = true; postfix_expression = perform_koenig_lookup (postfix_expression, args); } else if (TREE_CODE (postfix_expression) == IDENTIFIER_NODE) postfix_expression = unqualified_fn_lookup_error (postfix_expression); } if (TREE_CODE (postfix_expression) == COMPONENT_REF) { tree instance = TREE_OPERAND (postfix_expression, 0); tree fn = TREE_OPERAND (postfix_expression, 1); if (processing_template_decl && (type_dependent_expression_p (instance) || (!BASELINK_P (fn) && TREE_CODE (fn) != FIELD_DECL) || type_dependent_expression_p (fn) || any_type_dependent_arguments_p (args))) { postfix_expression = build_min_nt (CALL_EXPR, postfix_expression, args); break; } if (BASELINK_P (fn)) postfix_expression = (build_new_method_call (instance, fn, args, NULL_TREE, (idk == CP_ID_KIND_QUALIFIED ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL))); else postfix_expression = finish_call_expr (postfix_expression, args, /*disallow_virtual=*/false, /*koenig_p=*/false); } else if (TREE_CODE (postfix_expression) == OFFSET_REF || TREE_CODE (postfix_expression) == MEMBER_REF || TREE_CODE (postfix_expression) == DOTSTAR_EXPR) postfix_expression = (build_offset_ref_call_from_tree (postfix_expression, args)); else if (idk == CP_ID_KIND_QUALIFIED) /* A call to a static class member, or a namespace-scope function. */ postfix_expression = finish_call_expr (postfix_expression, args, /*disallow_virtual=*/true, koenig_p); else /* All other function calls. */ postfix_expression = finish_call_expr (postfix_expression, args, /*disallow_virtual=*/false, koenig_p); /* The POSTFIX_EXPRESSION is certainly no longer an id. */ idk = CP_ID_KIND_NONE; } break; case CPP_DOT: case CPP_DEREF: /* postfix-expression . template [opt] id-expression postfix-expression . pseudo-destructor-name postfix-expression -> template [opt] id-expression postfix-expression -> pseudo-destructor-name */ { tree name; bool dependent_p; bool template_p; tree scope = NULL_TREE; enum cpp_ttype token_type = token->type; /* If this is a `->' operator, dereference the pointer. */ if (token->type == CPP_DEREF) postfix_expression = build_x_arrow (postfix_expression); /* Check to see whether or not the expression is type-dependent. */ dependent_p = type_dependent_expression_p (postfix_expression); /* The identifier following the `->' or `.' is not qualified. */ parser->scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; parser->object_scope = NULL_TREE; idk = CP_ID_KIND_NONE; /* Enter the scope corresponding to the type of the object given by the POSTFIX_EXPRESSION. */ if (!dependent_p && TREE_TYPE (postfix_expression) != NULL_TREE) { scope = TREE_TYPE (postfix_expression); /* According to the standard, no expression should ever have reference type. Unfortunately, we do not currently match the standard in this respect in that our internal representation of an expression may have reference type even when the standard says it does not. Therefore, we have to manually obtain the underlying type here. */ scope = non_reference (scope); /* The type of the POSTFIX_EXPRESSION must be complete. */ scope = complete_type_or_else (scope, NULL_TREE); /* Let the name lookup machinery know that we are processing a class member access expression. */ parser->context->object_type = scope; /* If something went wrong, we want to be able to discern that case, as opposed to the case where there was no SCOPE due to the type of expression being dependent. */ if (!scope) scope = error_mark_node; /* If the SCOPE was erroneous, make the various semantic analysis functions exit quickly -- and without issuing additional error messages. */ if (scope == error_mark_node) postfix_expression = error_mark_node; } /* Consume the `.' or `->' operator. */ cp_lexer_consume_token (parser->lexer); /* If the SCOPE is not a scalar type, we are looking at an ordinary class member access expression, rather than a pseudo-destructor-name. */ if (!scope || !SCALAR_TYPE_P (scope)) { template_p = cp_parser_optional_template_keyword (parser); /* Parse the id-expression. */ name = cp_parser_id_expression (parser, template_p, /*check_dependency_p=*/true, /*template_p=*/NULL, /*declarator_p=*/false); /* In general, build a SCOPE_REF if the member name is qualified. However, if the name was not dependent and has already been resolved; there is no need to build the SCOPE_REF. For example; struct X { void f(); }; template void f(T* t) { t->X::f(); } Even though "t" is dependent, "X::f" is not and has been resolved to a BASELINK; there is no need to include scope information. */ /* But we do need to remember that there was an explicit scope for virtual function calls. */ if (parser->scope) idk = CP_ID_KIND_QUALIFIED; if (name != error_mark_node && !BASELINK_P (name) && parser->scope) { name = build_nt (SCOPE_REF, parser->scope, name); parser->scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; parser->object_scope = NULL_TREE; } if (scope && name && BASELINK_P (name)) adjust_result_of_qualified_name_lookup (name, BINFO_TYPE (BASELINK_BINFO (name)), scope); postfix_expression = finish_class_member_access_expr (postfix_expression, name); } /* Otherwise, try the pseudo-destructor-name production. */ else { tree s = NULL_TREE; tree type; /* Parse the pseudo-destructor-name. */ cp_parser_pseudo_destructor_name (parser, &s, &type); /* Form the call. */ postfix_expression = finish_pseudo_destructor_expr (postfix_expression, s, TREE_TYPE (type)); } /* We no longer need to look up names in the scope of the object on the left-hand side of the `.' or `->' operator. */ parser->context->object_type = NULL_TREE; /* These operators may not appear in constant-expressions. */ if (/* The "->" operator is allowed in the implementation of "offsetof". The "." operator may appear in the name of the member. */ !parser->in_offsetof_p && (cp_parser_non_integral_constant_expression (parser, token_type == CPP_DEREF ? "'->'" : "`.'"))) postfix_expression = error_mark_node; } break; case CPP_PLUS_PLUS: /* postfix-expression ++ */ /* Consume the `++' token. */ cp_lexer_consume_token (parser->lexer); /* Generate a representation for the complete expression. */ postfix_expression = finish_increment_expr (postfix_expression, POSTINCREMENT_EXPR); /* Increments may not appear in constant-expressions. */ if (cp_parser_non_integral_constant_expression (parser, "an increment")) postfix_expression = error_mark_node; idk = CP_ID_KIND_NONE; break; case CPP_MINUS_MINUS: /* postfix-expression -- */ /* Consume the `--' token. */ cp_lexer_consume_token (parser->lexer); /* Generate a representation for the complete expression. */ postfix_expression = finish_increment_expr (postfix_expression, POSTDECREMENT_EXPR); /* Decrements may not appear in constant-expressions. */ if (cp_parser_non_integral_constant_expression (parser, "a decrement")) postfix_expression = error_mark_node; idk = CP_ID_KIND_NONE; break; default: return postfix_expression; } } /* We should never get here. */ abort (); return error_mark_node; } /* Parse a parenthesized expression-list. expression-list: assignment-expression expression-list, assignment-expression attribute-list: expression-list identifier identifier, expression-list Returns a TREE_LIST. The TREE_VALUE of each node is a representation of an assignment-expression. Note that a TREE_LIST is returned even if there is only a single expression in the list. error_mark_node is returned if the ( and or ) are missing. NULL_TREE is returned on no expressions. The parentheses are eaten. IS_ATTRIBUTE_LIST is true if this is really an attribute list being parsed. If NON_CONSTANT_P is non-NULL, *NON_CONSTANT_P indicates whether or not all of the expressions in the list were constant. */ static tree cp_parser_parenthesized_expression_list (cp_parser* parser, bool is_attribute_list, bool *non_constant_p) { tree expression_list = NULL_TREE; tree identifier = NULL_TREE; /* Assume all the expressions will be constant. */ if (non_constant_p) *non_constant_p = false; if (!cp_parser_require (parser, CPP_OPEN_PAREN, "`('")) return error_mark_node; /* Consume expressions until there are no more. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN)) while (true) { tree expr; /* At the beginning of attribute lists, check to see if the next token is an identifier. */ if (is_attribute_list && cp_lexer_peek_token (parser->lexer)->type == CPP_NAME) { cp_token *token; /* Consume the identifier. */ token = cp_lexer_consume_token (parser->lexer); /* Save the identifier. */ identifier = token->value; } else { /* Parse the next assignment-expression. */ if (non_constant_p) { bool expr_non_constant_p; expr = (cp_parser_constant_expression (parser, /*allow_non_constant_p=*/true, &expr_non_constant_p)); if (expr_non_constant_p) *non_constant_p = true; } else expr = cp_parser_assignment_expression (parser); /* Add it to the list. We add error_mark_node expressions to the list, so that we can still tell if the correct form for a parenthesized expression-list is found. That gives better errors. */ expression_list = tree_cons (NULL_TREE, expr, expression_list); if (expr == error_mark_node) goto skip_comma; } /* After the first item, attribute lists look the same as expression lists. */ is_attribute_list = false; get_comma:; /* If the next token isn't a `,', then we are done. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) break; /* Otherwise, consume the `,' and keep going. */ cp_lexer_consume_token (parser->lexer); } if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) { int ending; skip_comma:; /* We try and resync to an unnested comma, as that will give the user better diagnostics. */ ending = cp_parser_skip_to_closing_parenthesis (parser, /*recovering=*/true, /*or_comma=*/true, /*consume_paren=*/true); if (ending < 0) goto get_comma; if (!ending) return error_mark_node; } /* We built up the list in reverse order so we must reverse it now. */ expression_list = nreverse (expression_list); if (identifier) expression_list = tree_cons (NULL_TREE, identifier, expression_list); return expression_list; } /* Parse a pseudo-destructor-name. pseudo-destructor-name: :: [opt] nested-name-specifier [opt] type-name :: ~ type-name :: [opt] nested-name-specifier template template-id :: ~ type-name :: [opt] nested-name-specifier [opt] ~ type-name If either of the first two productions is used, sets *SCOPE to the TYPE specified before the final `::'. Otherwise, *SCOPE is set to NULL_TREE. *TYPE is set to the TYPE_DECL for the final type-name, or ERROR_MARK_NODE if the parse fails. */ static void cp_parser_pseudo_destructor_name (cp_parser* parser, tree* scope, tree* type) { bool nested_name_specifier_p; /* Look for the optional `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/true); /* Look for the optional nested-name-specifier. */ nested_name_specifier_p = (cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/true) != NULL_TREE); /* Now, if we saw a nested-name-specifier, we might be doing the second production. */ if (nested_name_specifier_p && cp_lexer_next_token_is_keyword (parser->lexer, RID_TEMPLATE)) { /* Consume the `template' keyword. */ cp_lexer_consume_token (parser->lexer); /* Parse the template-id. */ cp_parser_template_id (parser, /*template_keyword_p=*/true, /*check_dependency_p=*/false, /*is_declaration=*/true); /* Look for the `::' token. */ cp_parser_require (parser, CPP_SCOPE, "`::'"); } /* If the next token is not a `~', then there might be some additional qualification. */ else if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMPL)) { /* Look for the type-name. */ *scope = TREE_TYPE (cp_parser_type_name (parser)); /* If we didn't get an aggregate type, or we don't have ::~, then something has gone wrong. Since the only caller of this function is looking for something after `.' or `->' after a scalar type, most likely the program is trying to get a member of a non-aggregate type. */ if (*scope == error_mark_node || cp_lexer_next_token_is_not (parser->lexer, CPP_SCOPE) || cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_COMPL) { cp_parser_error (parser, "request for member of non-aggregate type"); *type = error_mark_node; return; } /* Look for the `::' token. */ cp_parser_require (parser, CPP_SCOPE, "`::'"); } else *scope = NULL_TREE; /* Look for the `~'. */ cp_parser_require (parser, CPP_COMPL, "`~'"); /* Look for the type-name again. We are not responsible for checking that it matches the first type-name. */ *type = cp_parser_type_name (parser); } /* Parse a unary-expression. unary-expression: postfix-expression ++ cast-expression -- cast-expression unary-operator cast-expression sizeof unary-expression sizeof ( type-id ) new-expression delete-expression GNU Extensions: unary-expression: __extension__ cast-expression __alignof__ unary-expression __alignof__ ( type-id ) __real__ cast-expression __imag__ cast-expression && identifier ADDRESS_P is true iff the unary-expression is appearing as the operand of the `&' operator. Returns a representation of the expression. */ static tree cp_parser_unary_expression (cp_parser *parser, bool address_p) { cp_token *token; enum tree_code unary_operator; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Some keywords give away the kind of expression. */ if (token->type == CPP_KEYWORD) { enum rid keyword = token->keyword; switch (keyword) { case RID_ALIGNOF: case RID_SIZEOF: { tree operand; enum tree_code op; op = keyword == RID_ALIGNOF ? ALIGNOF_EXPR : SIZEOF_EXPR; /* Consume the token. */ cp_lexer_consume_token (parser->lexer); /* Parse the operand. */ operand = cp_parser_sizeof_operand (parser, keyword); if (TYPE_P (operand)) return cxx_sizeof_or_alignof_type (operand, op, true); else return cxx_sizeof_or_alignof_expr (operand, op); } case RID_NEW: return cp_parser_new_expression (parser); case RID_DELETE: return cp_parser_delete_expression (parser); case RID_EXTENSION: { /* The saved value of the PEDANTIC flag. */ int saved_pedantic; tree expr; /* Save away the PEDANTIC flag. */ cp_parser_extension_opt (parser, &saved_pedantic); /* Parse the cast-expression. */ expr = cp_parser_simple_cast_expression (parser); /* Restore the PEDANTIC flag. */ pedantic = saved_pedantic; return expr; } case RID_REALPART: case RID_IMAGPART: { tree expression; /* Consume the `__real__' or `__imag__' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the cast-expression. */ expression = cp_parser_simple_cast_expression (parser); /* Create the complete representation. */ return build_x_unary_op ((keyword == RID_REALPART ? REALPART_EXPR : IMAGPART_EXPR), expression); } break; default: break; } } /* Look for the `:: new' and `:: delete', which also signal the beginning of a new-expression, or delete-expression, respectively. If the next token is `::', then it might be one of these. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)) { enum rid keyword; /* See if the token after the `::' is one of the keywords in which we're interested. */ keyword = cp_lexer_peek_nth_token (parser->lexer, 2)->keyword; /* If it's `new', we have a new-expression. */ if (keyword == RID_NEW) return cp_parser_new_expression (parser); /* Similarly, for `delete'. */ else if (keyword == RID_DELETE) return cp_parser_delete_expression (parser); } /* Look for a unary operator. */ unary_operator = cp_parser_unary_operator (token); /* The `++' and `--' operators can be handled similarly, even though they are not technically unary-operators in the grammar. */ if (unary_operator == ERROR_MARK) { if (token->type == CPP_PLUS_PLUS) unary_operator = PREINCREMENT_EXPR; else if (token->type == CPP_MINUS_MINUS) unary_operator = PREDECREMENT_EXPR; /* Handle the GNU address-of-label extension. */ else if (cp_parser_allow_gnu_extensions_p (parser) && token->type == CPP_AND_AND) { tree identifier; /* Consume the '&&' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the identifier. */ identifier = cp_parser_identifier (parser); /* Create an expression representing the address. */ return finish_label_address_expr (identifier); } } if (unary_operator != ERROR_MARK) { tree cast_expression; tree expression = error_mark_node; const char *non_constant_p = NULL; /* Consume the operator token. */ token = cp_lexer_consume_token (parser->lexer); /* Parse the cast-expression. */ cast_expression = cp_parser_cast_expression (parser, unary_operator == ADDR_EXPR); /* Now, build an appropriate representation. */ switch (unary_operator) { case INDIRECT_REF: non_constant_p = "`*'"; expression = build_x_indirect_ref (cast_expression, "unary *"); break; case ADDR_EXPR: /* The "&" operator is allowed in the implementation of "offsetof". */ if (!parser->in_offsetof_p) non_constant_p = "`&'"; /* Fall through. */ case BIT_NOT_EXPR: expression = build_x_unary_op (unary_operator, cast_expression); break; case PREINCREMENT_EXPR: case PREDECREMENT_EXPR: non_constant_p = (unary_operator == PREINCREMENT_EXPR ? "`++'" : "`--'"); /* Fall through. */ case CONVERT_EXPR: case NEGATE_EXPR: case TRUTH_NOT_EXPR: expression = finish_unary_op_expr (unary_operator, cast_expression); break; default: abort (); } if (non_constant_p && cp_parser_non_integral_constant_expression (parser, non_constant_p)) expression = error_mark_node; return expression; } return cp_parser_postfix_expression (parser, address_p); } /* Returns ERROR_MARK if TOKEN is not a unary-operator. If TOKEN is a unary-operator, the corresponding tree code is returned. */ static enum tree_code cp_parser_unary_operator (cp_token* token) { switch (token->type) { case CPP_MULT: return INDIRECT_REF; case CPP_AND: return ADDR_EXPR; case CPP_PLUS: return CONVERT_EXPR; case CPP_MINUS: return NEGATE_EXPR; case CPP_NOT: return TRUTH_NOT_EXPR; case CPP_COMPL: return BIT_NOT_EXPR; default: return ERROR_MARK; } } /* Parse a new-expression. new-expression: :: [opt] new new-placement [opt] new-type-id new-initializer [opt] :: [opt] new new-placement [opt] ( type-id ) new-initializer [opt] Returns a representation of the expression. */ static tree cp_parser_new_expression (cp_parser* parser) { bool global_scope_p; tree placement; tree type; tree initializer; /* Look for the optional `::' operator. */ global_scope_p = (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false) != NULL_TREE); /* Look for the `new' operator. */ cp_parser_require_keyword (parser, RID_NEW, "`new'"); /* There's no easy way to tell a new-placement from the `( type-id )' construct. */ cp_parser_parse_tentatively (parser); /* Look for a new-placement. */ placement = cp_parser_new_placement (parser); /* If that didn't work out, there's no new-placement. */ if (!cp_parser_parse_definitely (parser)) placement = NULL_TREE; /* If the next token is a `(', then we have a parenthesized type-id. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN)) { /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* Parse the type-id. */ type = cp_parser_type_id (parser); /* Look for the closing `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* There should not be a direct-new-declarator in this production, but GCC used to allowed this, so we check and emit a sensible error message for this case. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_SQUARE)) { error ("array bound forbidden after parenthesized type-id"); inform ("try removing the parentheses around the type-id"); cp_parser_direct_new_declarator (parser); } } /* Otherwise, there must be a new-type-id. */ else type = cp_parser_new_type_id (parser); /* If the next token is a `(', then we have a new-initializer. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN)) initializer = cp_parser_new_initializer (parser); else initializer = NULL_TREE; /* A new-expression may not appear in an integral constant expression. */ if (cp_parser_non_integral_constant_expression (parser, "`new'")) return error_mark_node; /* Create a representation of the new-expression. */ return build_new (placement, type, initializer, global_scope_p); } /* Parse a new-placement. new-placement: ( expression-list ) Returns the same representation as for an expression-list. */ static tree cp_parser_new_placement (cp_parser* parser) { tree expression_list; /* Parse the expression-list. */ expression_list = (cp_parser_parenthesized_expression_list (parser, false, /*non_constant_p=*/NULL)); return expression_list; } /* Parse a new-type-id. new-type-id: type-specifier-seq new-declarator [opt] Returns a TREE_LIST whose TREE_PURPOSE is the type-specifier-seq, and whose TREE_VALUE is the new-declarator. */ static tree cp_parser_new_type_id (cp_parser* parser) { tree type_specifier_seq; tree declarator; const char *saved_message; /* The type-specifier sequence must not contain type definitions. (It cannot contain declarations of new types either, but if they are not definitions we will catch that because they are not complete.) */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in a new-type-id"; /* Parse the type-specifier-seq. */ type_specifier_seq = cp_parser_type_specifier_seq (parser); /* Restore the old message. */ parser->type_definition_forbidden_message = saved_message; /* Parse the new-declarator. */ declarator = cp_parser_new_declarator_opt (parser); return build_tree_list (type_specifier_seq, declarator); } /* Parse an (optional) new-declarator. new-declarator: ptr-operator new-declarator [opt] direct-new-declarator Returns a representation of the declarator. See cp_parser_declarator for the representations used. */ static tree cp_parser_new_declarator_opt (cp_parser* parser) { enum tree_code code; tree type; tree cv_qualifier_seq; /* We don't know if there's a ptr-operator next, or not. */ cp_parser_parse_tentatively (parser); /* Look for a ptr-operator. */ code = cp_parser_ptr_operator (parser, &type, &cv_qualifier_seq); /* If that worked, look for more new-declarators. */ if (cp_parser_parse_definitely (parser)) { tree declarator; /* Parse another optional declarator. */ declarator = cp_parser_new_declarator_opt (parser); /* Create the representation of the declarator. */ if (code == INDIRECT_REF) declarator = make_pointer_declarator (cv_qualifier_seq, declarator); else declarator = make_reference_declarator (cv_qualifier_seq, declarator); /* Handle the pointer-to-member case. */ if (type) declarator = build_nt (SCOPE_REF, type, declarator); return declarator; } /* If the next token is a `[', there is a direct-new-declarator. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_SQUARE)) return cp_parser_direct_new_declarator (parser); return NULL_TREE; } /* Parse a direct-new-declarator. direct-new-declarator: [ expression ] direct-new-declarator [constant-expression] Returns an ARRAY_REF, following the same conventions as are documented for cp_parser_direct_declarator. */ static tree cp_parser_direct_new_declarator (cp_parser* parser) { tree declarator = NULL_TREE; while (true) { tree expression; /* Look for the opening `['. */ cp_parser_require (parser, CPP_OPEN_SQUARE, "`['"); /* The first expression is not required to be constant. */ if (!declarator) { expression = cp_parser_expression (parser); /* The standard requires that the expression have integral type. DR 74 adds enumeration types. We believe that the real intent is that these expressions be handled like the expression in a `switch' condition, which also allows classes with a single conversion to integral or enumeration type. */ if (!processing_template_decl) { expression = build_expr_type_conversion (WANT_INT | WANT_ENUM, expression, /*complain=*/true); if (!expression) { error ("expression in new-declarator must have integral or enumeration type"); expression = error_mark_node; } } } /* But all the other expressions must be. */ else expression = cp_parser_constant_expression (parser, /*allow_non_constant=*/false, NULL); /* Look for the closing `]'. */ cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'"); /* Add this bound to the declarator. */ declarator = build_nt (ARRAY_REF, declarator, expression); /* If the next token is not a `[', then there are no more bounds. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_SQUARE)) break; } return declarator; } /* Parse a new-initializer. new-initializer: ( expression-list [opt] ) Returns a representation of the expression-list. If there is no expression-list, VOID_ZERO_NODE is returned. */ static tree cp_parser_new_initializer (cp_parser* parser) { tree expression_list; expression_list = (cp_parser_parenthesized_expression_list (parser, false, /*non_constant_p=*/NULL)); if (!expression_list) expression_list = void_zero_node; return expression_list; } /* Parse a delete-expression. delete-expression: :: [opt] delete cast-expression :: [opt] delete [ ] cast-expression Returns a representation of the expression. */ static tree cp_parser_delete_expression (cp_parser* parser) { bool global_scope_p; bool array_p; tree expression; /* Look for the optional `::' operator. */ global_scope_p = (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false) != NULL_TREE); /* Look for the `delete' keyword. */ cp_parser_require_keyword (parser, RID_DELETE, "`delete'"); /* See if the array syntax is in use. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_SQUARE)) { /* Consume the `[' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the `]' token. */ cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'"); /* Remember that this is the `[]' construct. */ array_p = true; } else array_p = false; /* Parse the cast-expression. */ expression = cp_parser_simple_cast_expression (parser); /* A delete-expression may not appear in an integral constant expression. */ if (cp_parser_non_integral_constant_expression (parser, "`delete'")) return error_mark_node; return delete_sanity (expression, NULL_TREE, array_p, global_scope_p); } /* Parse a cast-expression. cast-expression: unary-expression ( type-id ) cast-expression Returns a representation of the expression. */ static tree cp_parser_cast_expression (cp_parser *parser, bool address_p) { /* If it's a `(', then we might be looking at a cast. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN)) { tree type = NULL_TREE; tree expr = NULL_TREE; bool compound_literal_p; const char *saved_message; /* There's no way to know yet whether or not this is a cast. For example, `(int (3))' is a unary-expression, while `(int) 3' is a cast. So, we resort to parsing tentatively. */ cp_parser_parse_tentatively (parser); /* Types may not be defined in a cast. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in casts"; /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* A very tricky bit is that `(struct S) { 3 }' is a compound-literal (which we permit in C++ as an extension). But, that construct is not a cast-expression -- it is a postfix-expression. (The reason is that `(struct S) { 3 }.i' is legal; if the compound-literal were a cast-expression, you'd need an extra set of parentheses.) But, if we parse the type-id, and it happens to be a class-specifier, then we will commit to the parse at that point, because we cannot undo the action that is done when creating a new class. So, then we cannot back up and do a postfix-expression. Therefore, we scan ahead to the closing `)', and check to see if the token after the `)' is a `{'. If so, we are not looking at a cast-expression. Save tokens so that we can put them back. */ cp_lexer_save_tokens (parser->lexer); /* Skip tokens until the next token is a closing parenthesis. If we find the closing `)', and the next token is a `{', then we are looking at a compound-literal. */ compound_literal_p = (cp_parser_skip_to_closing_parenthesis (parser, false, false, /*consume_paren=*/true) && cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE)); /* Roll back the tokens we skipped. */ cp_lexer_rollback_tokens (parser->lexer); /* If we were looking at a compound-literal, simulate an error so that the call to cp_parser_parse_definitely below will fail. */ if (compound_literal_p) cp_parser_simulate_error (parser); else { bool saved_in_type_id_in_expr_p = parser->in_type_id_in_expr_p; parser->in_type_id_in_expr_p = true; /* Look for the type-id. */ type = cp_parser_type_id (parser); /* Look for the closing `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); parser->in_type_id_in_expr_p = saved_in_type_id_in_expr_p; } /* Restore the saved message. */ parser->type_definition_forbidden_message = saved_message; /* If ok so far, parse the dependent expression. We cannot be sure it is a cast. Consider `(T ())'. It is a parenthesized ctor of T, but looks like a cast to function returning T without a dependent expression. */ if (!cp_parser_error_occurred (parser)) expr = cp_parser_simple_cast_expression (parser); if (cp_parser_parse_definitely (parser)) { /* Warn about old-style casts, if so requested. */ if (warn_old_style_cast && !in_system_header && !VOID_TYPE_P (type) && current_lang_name != lang_name_c) warning ("use of old-style cast"); /* Only type conversions to integral or enumeration types can be used in constant-expressions. */ if (parser->integral_constant_expression_p && !dependent_type_p (type) && !INTEGRAL_OR_ENUMERATION_TYPE_P (type) && (cp_parser_non_integral_constant_expression (parser, "a casts to a type other than an integral or " "enumeration type"))) return error_mark_node; /* Perform the cast. */ expr = build_c_cast (type, expr); return expr; } } /* If we get here, then it's not a cast, so it must be a unary-expression. */ return cp_parser_unary_expression (parser, address_p); } /* Parse a pm-expression. pm-expression: cast-expression pm-expression .* cast-expression pm-expression ->* cast-expression Returns a representation of the expression. */ static tree cp_parser_pm_expression (cp_parser* parser) { static const cp_parser_token_tree_map map = { { CPP_DEREF_STAR, MEMBER_REF }, { CPP_DOT_STAR, DOTSTAR_EXPR }, { CPP_EOF, ERROR_MARK } }; return cp_parser_binary_expression (parser, map, cp_parser_simple_cast_expression); } /* Parse a multiplicative-expression. mulitplicative-expression: pm-expression multiplicative-expression * pm-expression multiplicative-expression / pm-expression multiplicative-expression % pm-expression Returns a representation of the expression. */ static tree cp_parser_multiplicative_expression (cp_parser* parser) { static const cp_parser_token_tree_map map = { { CPP_MULT, MULT_EXPR }, { CPP_DIV, TRUNC_DIV_EXPR }, { CPP_MOD, TRUNC_MOD_EXPR }, { CPP_EOF, ERROR_MARK } }; return cp_parser_binary_expression (parser, map, cp_parser_pm_expression); } /* Parse an additive-expression. additive-expression: multiplicative-expression additive-expression + multiplicative-expression additive-expression - multiplicative-expression Returns a representation of the expression. */ static tree cp_parser_additive_expression (cp_parser* parser) { static const cp_parser_token_tree_map map = { { CPP_PLUS, PLUS_EXPR }, { CPP_MINUS, MINUS_EXPR }, { CPP_EOF, ERROR_MARK } }; return cp_parser_binary_expression (parser, map, cp_parser_multiplicative_expression); } /* Parse a shift-expression. shift-expression: additive-expression shift-expression << additive-expression shift-expression >> additive-expression Returns a representation of the expression. */ static tree cp_parser_shift_expression (cp_parser* parser) { static const cp_parser_token_tree_map map = { { CPP_LSHIFT, LSHIFT_EXPR }, { CPP_RSHIFT, RSHIFT_EXPR }, { CPP_EOF, ERROR_MARK } }; return cp_parser_binary_expression (parser, map, cp_parser_additive_expression); } /* Parse a relational-expression. relational-expression: shift-expression relational-expression < shift-expression relational-expression > shift-expression relational-expression <= shift-expression relational-expression >= shift-expression GNU Extension: relational-expression: relational-expression ? shift-expression Returns a representation of the expression. */ static tree cp_parser_relational_expression (cp_parser* parser) { static const cp_parser_token_tree_map map = { { CPP_LESS, LT_EXPR }, { CPP_GREATER, GT_EXPR }, { CPP_LESS_EQ, LE_EXPR }, { CPP_GREATER_EQ, GE_EXPR }, { CPP_MIN, MIN_EXPR }, { CPP_MAX, MAX_EXPR }, { CPP_EOF, ERROR_MARK } }; return cp_parser_binary_expression (parser, map, cp_parser_shift_expression); } /* Parse an equality-expression. equality-expression: relational-expression equality-expression == relational-expression equality-expression != relational-expression Returns a representation of the expression. */ static tree cp_parser_equality_expression (cp_parser* parser) { static const cp_parser_token_tree_map map = { { CPP_EQ_EQ, EQ_EXPR }, { CPP_NOT_EQ, NE_EXPR }, { CPP_EOF, ERROR_MARK } }; return cp_parser_binary_expression (parser, map, cp_parser_relational_expression); } /* Parse an and-expression. and-expression: equality-expression and-expression & equality-expression Returns a representation of the expression. */ static tree cp_parser_and_expression (cp_parser* parser) { static const cp_parser_token_tree_map map = { { CPP_AND, BIT_AND_EXPR }, { CPP_EOF, ERROR_MARK } }; return cp_parser_binary_expression (parser, map, cp_parser_equality_expression); } /* Parse an exclusive-or-expression. exclusive-or-expression: and-expression exclusive-or-expression ^ and-expression Returns a representation of the expression. */ static tree cp_parser_exclusive_or_expression (cp_parser* parser) { static const cp_parser_token_tree_map map = { { CPP_XOR, BIT_XOR_EXPR }, { CPP_EOF, ERROR_MARK } }; return cp_parser_binary_expression (parser, map, cp_parser_and_expression); } /* Parse an inclusive-or-expression. inclusive-or-expression: exclusive-or-expression inclusive-or-expression | exclusive-or-expression Returns a representation of the expression. */ static tree cp_parser_inclusive_or_expression (cp_parser* parser) { static const cp_parser_token_tree_map map = { { CPP_OR, BIT_IOR_EXPR }, { CPP_EOF, ERROR_MARK } }; return cp_parser_binary_expression (parser, map, cp_parser_exclusive_or_expression); } /* Parse a logical-and-expression. logical-and-expression: inclusive-or-expression logical-and-expression && inclusive-or-expression Returns a representation of the expression. */ static tree cp_parser_logical_and_expression (cp_parser* parser) { static const cp_parser_token_tree_map map = { { CPP_AND_AND, TRUTH_ANDIF_EXPR }, { CPP_EOF, ERROR_MARK } }; return cp_parser_binary_expression (parser, map, cp_parser_inclusive_or_expression); } /* Parse a logical-or-expression. logical-or-expression: logical-and-expression logical-or-expression || logical-and-expression Returns a representation of the expression. */ static tree cp_parser_logical_or_expression (cp_parser* parser) { static const cp_parser_token_tree_map map = { { CPP_OR_OR, TRUTH_ORIF_EXPR }, { CPP_EOF, ERROR_MARK } }; return cp_parser_binary_expression (parser, map, cp_parser_logical_and_expression); } /* Parse the `? expression : assignment-expression' part of a conditional-expression. The LOGICAL_OR_EXPR is the logical-or-expression that started the conditional-expression. Returns a representation of the entire conditional-expression. This routine is used by cp_parser_assignment_expression. ? expression : assignment-expression GNU Extensions: ? : assignment-expression */ static tree cp_parser_question_colon_clause (cp_parser* parser, tree logical_or_expr) { tree expr; tree assignment_expr; /* Consume the `?' token. */ cp_lexer_consume_token (parser->lexer); if (cp_parser_allow_gnu_extensions_p (parser) && cp_lexer_next_token_is (parser->lexer, CPP_COLON)) /* Implicit true clause. */ expr = NULL_TREE; else /* Parse the expression. */ expr = cp_parser_expression (parser); /* The next token should be a `:'. */ cp_parser_require (parser, CPP_COLON, "`:'"); /* Parse the assignment-expression. */ assignment_expr = cp_parser_assignment_expression (parser); /* Build the conditional-expression. */ return build_x_conditional_expr (logical_or_expr, expr, assignment_expr); } /* Parse an assignment-expression. assignment-expression: conditional-expression logical-or-expression assignment-operator assignment_expression throw-expression Returns a representation for the expression. */ static tree cp_parser_assignment_expression (cp_parser* parser) { tree expr; /* If the next token is the `throw' keyword, then we're looking at a throw-expression. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_THROW)) expr = cp_parser_throw_expression (parser); /* Otherwise, it must be that we are looking at a logical-or-expression. */ else { /* Parse the logical-or-expression. */ expr = cp_parser_logical_or_expression (parser); /* If the next token is a `?' then we're actually looking at a conditional-expression. */ if (cp_lexer_next_token_is (parser->lexer, CPP_QUERY)) return cp_parser_question_colon_clause (parser, expr); else { enum tree_code assignment_operator; /* If it's an assignment-operator, we're using the second production. */ assignment_operator = cp_parser_assignment_operator_opt (parser); if (assignment_operator != ERROR_MARK) { tree rhs; /* Parse the right-hand side of the assignment. */ rhs = cp_parser_assignment_expression (parser); /* An assignment may not appear in a constant-expression. */ if (cp_parser_non_integral_constant_expression (parser, "an assignment")) return error_mark_node; /* Build the assignment expression. */ expr = build_x_modify_expr (expr, assignment_operator, rhs); } } } return expr; } /* Parse an (optional) assignment-operator. assignment-operator: one of = *= /= %= += -= >>= <<= &= ^= |= GNU Extension: assignment-operator: one of ?= If the next token is an assignment operator, the corresponding tree code is returned, and the token is consumed. For example, for `+=', PLUS_EXPR is returned. For `=' itself, the code returned is NOP_EXPR. For `/', TRUNC_DIV_EXPR is returned; for `%', TRUNC_MOD_EXPR is returned. If TOKEN is not an assignment operator, ERROR_MARK is returned. */ static enum tree_code cp_parser_assignment_operator_opt (cp_parser* parser) { enum tree_code op; cp_token *token; /* Peek at the next toen. */ token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_EQ: op = NOP_EXPR; break; case CPP_MULT_EQ: op = MULT_EXPR; break; case CPP_DIV_EQ: op = TRUNC_DIV_EXPR; break; case CPP_MOD_EQ: op = TRUNC_MOD_EXPR; break; case CPP_PLUS_EQ: op = PLUS_EXPR; break; case CPP_MINUS_EQ: op = MINUS_EXPR; break; case CPP_RSHIFT_EQ: op = RSHIFT_EXPR; break; case CPP_LSHIFT_EQ: op = LSHIFT_EXPR; break; case CPP_AND_EQ: op = BIT_AND_EXPR; break; case CPP_XOR_EQ: op = BIT_XOR_EXPR; break; case CPP_OR_EQ: op = BIT_IOR_EXPR; break; case CPP_MIN_EQ: op = MIN_EXPR; break; case CPP_MAX_EQ: op = MAX_EXPR; break; default: /* Nothing else is an assignment operator. */ op = ERROR_MARK; } /* If it was an assignment operator, consume it. */ if (op != ERROR_MARK) cp_lexer_consume_token (parser->lexer); return op; } /* Parse an expression. expression: assignment-expression expression , assignment-expression Returns a representation of the expression. */ static tree cp_parser_expression (cp_parser* parser) { tree expression = NULL_TREE; while (true) { tree assignment_expression; /* Parse the next assignment-expression. */ assignment_expression = cp_parser_assignment_expression (parser); /* If this is the first assignment-expression, we can just save it away. */ if (!expression) expression = assignment_expression; else expression = build_x_compound_expr (expression, assignment_expression); /* If the next token is not a comma, then we are done with the expression. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) break; /* Consume the `,'. */ cp_lexer_consume_token (parser->lexer); /* A comma operator cannot appear in a constant-expression. */ if (cp_parser_non_integral_constant_expression (parser, "a comma operator")) expression = error_mark_node; } return expression; } /* Parse a constant-expression. constant-expression: conditional-expression If ALLOW_NON_CONSTANT_P a non-constant expression is silently accepted. If ALLOW_NON_CONSTANT_P is true and the expression is not constant, *NON_CONSTANT_P is set to TRUE. If ALLOW_NON_CONSTANT_P is false, NON_CONSTANT_P should be NULL. */ static tree cp_parser_constant_expression (cp_parser* parser, bool allow_non_constant_p, bool *non_constant_p) { bool saved_integral_constant_expression_p; bool saved_allow_non_integral_constant_expression_p; bool saved_non_integral_constant_expression_p; tree expression; /* It might seem that we could simply parse the conditional-expression, and then check to see if it were TREE_CONSTANT. However, an expression that is TREE_CONSTANT is one that the compiler can figure out is constant, possibly after doing some simplifications or optimizations. The standard has a precise definition of constant-expression, and we must honor that, even though it is somewhat more restrictive. For example: int i[(2, 3)]; is not a legal declaration, because `(2, 3)' is not a constant-expression. The `,' operator is forbidden in a constant-expression. However, GCC's constant-folding machinery will fold this operation to an INTEGER_CST for `3'. */ /* Save the old settings. */ saved_integral_constant_expression_p = parser->integral_constant_expression_p; saved_allow_non_integral_constant_expression_p = parser->allow_non_integral_constant_expression_p; saved_non_integral_constant_expression_p = parser->non_integral_constant_expression_p; /* We are now parsing a constant-expression. */ parser->integral_constant_expression_p = true; parser->allow_non_integral_constant_expression_p = allow_non_constant_p; parser->non_integral_constant_expression_p = false; /* Although the grammar says "conditional-expression", we parse an "assignment-expression", which also permits "throw-expression" and the use of assignment operators. In the case that ALLOW_NON_CONSTANT_P is false, we get better errors than we would otherwise. In the case that ALLOW_NON_CONSTANT_P is true, it is actually essential that we look for an assignment-expression. For example, cp_parser_initializer_clauses uses this function to determine whether a particular assignment-expression is in fact constant. */ expression = cp_parser_assignment_expression (parser); /* Restore the old settings. */ parser->integral_constant_expression_p = saved_integral_constant_expression_p; parser->allow_non_integral_constant_expression_p = saved_allow_non_integral_constant_expression_p; if (allow_non_constant_p) *non_constant_p = parser->non_integral_constant_expression_p; parser->non_integral_constant_expression_p = saved_non_integral_constant_expression_p; return expression; } /* Statements [gram.stmt.stmt] */ /* Parse a statement. statement: labeled-statement expression-statement compound-statement selection-statement iteration-statement jump-statement declaration-statement try-block */ static void cp_parser_statement (cp_parser* parser, bool in_statement_expr_p) { tree statement; cp_token *token; int statement_line_number; /* There is no statement yet. */ statement = NULL_TREE; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Remember the line number of the first token in the statement. */ statement_line_number = token->location.line; /* If this is a keyword, then that will often determine what kind of statement we have. */ if (token->type == CPP_KEYWORD) { enum rid keyword = token->keyword; switch (keyword) { case RID_CASE: case RID_DEFAULT: statement = cp_parser_labeled_statement (parser, in_statement_expr_p); break; case RID_IF: case RID_SWITCH: statement = cp_parser_selection_statement (parser); break; case RID_WHILE: case RID_DO: case RID_FOR: statement = cp_parser_iteration_statement (parser); break; case RID_BREAK: case RID_CONTINUE: case RID_RETURN: case RID_GOTO: statement = cp_parser_jump_statement (parser); break; case RID_TRY: statement = cp_parser_try_block (parser); break; default: /* It might be a keyword like `int' that can start a declaration-statement. */ break; } } else if (token->type == CPP_NAME) { /* If the next token is a `:', then we are looking at a labeled-statement. */ token = cp_lexer_peek_nth_token (parser->lexer, 2); if (token->type == CPP_COLON) statement = cp_parser_labeled_statement (parser, in_statement_expr_p); } /* Anything that starts with a `{' must be a compound-statement. */ else if (token->type == CPP_OPEN_BRACE) statement = cp_parser_compound_statement (parser, false); /* Everything else must be a declaration-statement or an expression-statement. Try for the declaration-statement first, unless we are looking at a `;', in which case we know that we have an expression-statement. */ if (!statement) { if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) { cp_parser_parse_tentatively (parser); /* Try to parse the declaration-statement. */ cp_parser_declaration_statement (parser); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) return; } /* Look for an expression-statement instead. */ statement = cp_parser_expression_statement (parser, in_statement_expr_p); } /* Set the line number for the statement. */ if (statement && STATEMENT_CODE_P (TREE_CODE (statement))) STMT_LINENO (statement) = statement_line_number; } /* Parse a labeled-statement. labeled-statement: identifier : statement case constant-expression : statement default : statement GNU Extension: labeled-statement: case constant-expression ... constant-expression : statement Returns the new CASE_LABEL, for a `case' or `default' label. For an ordinary label, returns a LABEL_STMT. */ static tree cp_parser_labeled_statement (cp_parser* parser, bool in_statement_expr_p) { cp_token *token; tree statement = error_mark_node; /* The next token should be an identifier. */ token = cp_lexer_peek_token (parser->lexer); if (token->type != CPP_NAME && token->type != CPP_KEYWORD) { cp_parser_error (parser, "expected labeled-statement"); return error_mark_node; } switch (token->keyword) { case RID_CASE: { tree expr, expr_hi; cp_token *ellipsis; /* Consume the `case' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the constant-expression. */ expr = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/false, NULL); ellipsis = cp_lexer_peek_token (parser->lexer); if (ellipsis->type == CPP_ELLIPSIS) { /* Consume the `...' token. */ cp_lexer_consume_token (parser->lexer); expr_hi = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/false, NULL); /* We don't need to emit warnings here, as the common code will do this for us. */ } else expr_hi = NULL_TREE; if (!parser->in_switch_statement_p) error ("case label `%E' not within a switch statement", expr); else statement = finish_case_label (expr, expr_hi); } break; case RID_DEFAULT: /* Consume the `default' token. */ cp_lexer_consume_token (parser->lexer); if (!parser->in_switch_statement_p) error ("case label not within a switch statement"); else statement = finish_case_label (NULL_TREE, NULL_TREE); break; default: /* Anything else must be an ordinary label. */ statement = finish_label_stmt (cp_parser_identifier (parser)); break; } /* Require the `:' token. */ cp_parser_require (parser, CPP_COLON, "`:'"); /* Parse the labeled statement. */ cp_parser_statement (parser, in_statement_expr_p); /* Return the label, in the case of a `case' or `default' label. */ return statement; } /* Parse an expression-statement. expression-statement: expression [opt] ; Returns the new EXPR_STMT -- or NULL_TREE if the expression statement consists of nothing more than an `;'. IN_STATEMENT_EXPR_P indicates whether this expression-statement is part of an expression statement. */ static tree cp_parser_expression_statement (cp_parser* parser, bool in_statement_expr_p) { tree statement = NULL_TREE; /* If the next token is a ';', then there is no expression statement. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) statement = cp_parser_expression (parser); /* Consume the final `;'. */ cp_parser_consume_semicolon_at_end_of_statement (parser); if (in_statement_expr_p && cp_lexer_next_token_is (parser->lexer, CPP_CLOSE_BRACE)) { /* This is the final expression statement of a statement expression. */ statement = finish_stmt_expr_expr (statement); } else if (statement) statement = finish_expr_stmt (statement); else finish_stmt (); return statement; } /* Parse a compound-statement. compound-statement: { statement-seq [opt] } Returns a COMPOUND_STMT representing the statement. */ static tree cp_parser_compound_statement (cp_parser *parser, bool in_statement_expr_p) { tree compound_stmt; /* Consume the `{'. */ if (!cp_parser_require (parser, CPP_OPEN_BRACE, "`{'")) return error_mark_node; /* Begin the compound-statement. */ compound_stmt = begin_compound_stmt (/*has_no_scope=*/false); /* Parse an (optional) statement-seq. */ cp_parser_statement_seq_opt (parser, in_statement_expr_p); /* Finish the compound-statement. */ finish_compound_stmt (compound_stmt); /* Consume the `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); return compound_stmt; } /* Parse an (optional) statement-seq. statement-seq: statement statement-seq [opt] statement */ static void cp_parser_statement_seq_opt (cp_parser* parser, bool in_statement_expr_p) { /* Scan statements until there aren't any more. */ while (true) { /* If we're looking at a `}', then we've run out of statements. */ if (cp_lexer_next_token_is (parser->lexer, CPP_CLOSE_BRACE) || cp_lexer_next_token_is (parser->lexer, CPP_EOF)) break; /* Parse the statement. */ cp_parser_statement (parser, in_statement_expr_p); } } /* Parse a selection-statement. selection-statement: if ( condition ) statement if ( condition ) statement else statement switch ( condition ) statement Returns the new IF_STMT or SWITCH_STMT. */ static tree cp_parser_selection_statement (cp_parser* parser) { cp_token *token; enum rid keyword; /* Peek at the next token. */ token = cp_parser_require (parser, CPP_KEYWORD, "selection-statement"); /* See what kind of keyword it is. */ keyword = token->keyword; switch (keyword) { case RID_IF: case RID_SWITCH: { tree statement; tree condition; /* Look for the `('. */ if (!cp_parser_require (parser, CPP_OPEN_PAREN, "`('")) { cp_parser_skip_to_end_of_statement (parser); return error_mark_node; } /* Begin the selection-statement. */ if (keyword == RID_IF) statement = begin_if_stmt (); else statement = begin_switch_stmt (); /* Parse the condition. */ condition = cp_parser_condition (parser); /* Look for the `)'. */ if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) cp_parser_skip_to_closing_parenthesis (parser, true, false, /*consume_paren=*/true); if (keyword == RID_IF) { tree then_stmt; /* Add the condition. */ finish_if_stmt_cond (condition, statement); /* Parse the then-clause. */ then_stmt = cp_parser_implicitly_scoped_statement (parser); finish_then_clause (statement); /* If the next token is `else', parse the else-clause. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_ELSE)) { tree else_stmt; /* Consume the `else' keyword. */ cp_lexer_consume_token (parser->lexer); /* Parse the else-clause. */ else_stmt = cp_parser_implicitly_scoped_statement (parser); finish_else_clause (statement); } /* Now we're all done with the if-statement. */ finish_if_stmt (); } else { tree body; bool in_switch_statement_p; /* Add the condition. */ finish_switch_cond (condition, statement); /* Parse the body of the switch-statement. */ in_switch_statement_p = parser->in_switch_statement_p; parser->in_switch_statement_p = true; body = cp_parser_implicitly_scoped_statement (parser); parser->in_switch_statement_p = in_switch_statement_p; /* Now we're all done with the switch-statement. */ finish_switch_stmt (statement); } return statement; } break; default: cp_parser_error (parser, "expected selection-statement"); return error_mark_node; } } /* Parse a condition. condition: expression type-specifier-seq declarator = assignment-expression GNU Extension: condition: type-specifier-seq declarator asm-specification [opt] attributes [opt] = assignment-expression Returns the expression that should be tested. */ static tree cp_parser_condition (cp_parser* parser) { tree type_specifiers; const char *saved_message; /* Try the declaration first. */ cp_parser_parse_tentatively (parser); /* New types are not allowed in the type-specifier-seq for a condition. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in conditions"; /* Parse the type-specifier-seq. */ type_specifiers = cp_parser_type_specifier_seq (parser); /* Restore the saved message. */ parser->type_definition_forbidden_message = saved_message; /* If all is well, we might be looking at a declaration. */ if (!cp_parser_error_occurred (parser)) { tree decl; tree asm_specification; tree attributes; tree declarator; tree initializer = NULL_TREE; /* Parse the declarator. */ declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_NAMED, /*ctor_dtor_or_conv_p=*/NULL, /*parenthesized_p=*/NULL); /* Parse the attributes. */ attributes = cp_parser_attributes_opt (parser); /* Parse the asm-specification. */ asm_specification = cp_parser_asm_specification_opt (parser); /* If the next token is not an `=', then we might still be looking at an expression. For example: if (A(a).x) looks like a decl-specifier-seq and a declarator -- but then there is no `=', so this is an expression. */ cp_parser_require (parser, CPP_EQ, "`='"); /* If we did see an `=', then we are looking at a declaration for sure. */ if (cp_parser_parse_definitely (parser)) { /* Create the declaration. */ decl = start_decl (declarator, type_specifiers, /*initialized_p=*/true, attributes, /*prefix_attributes=*/NULL_TREE); /* Parse the assignment-expression. */ initializer = cp_parser_assignment_expression (parser); /* Process the initializer. */ cp_finish_decl (decl, initializer, asm_specification, LOOKUP_ONLYCONVERTING); return convert_from_reference (decl); } } /* If we didn't even get past the declarator successfully, we are definitely not looking at a declaration. */ else cp_parser_abort_tentative_parse (parser); /* Otherwise, we are looking at an expression. */ return cp_parser_expression (parser); } /* Parse an iteration-statement. iteration-statement: while ( condition ) statement do statement while ( expression ) ; for ( for-init-statement condition [opt] ; expression [opt] ) statement Returns the new WHILE_STMT, DO_STMT, or FOR_STMT. */ static tree cp_parser_iteration_statement (cp_parser* parser) { cp_token *token; enum rid keyword; tree statement; bool in_iteration_statement_p; /* Peek at the next token. */ token = cp_parser_require (parser, CPP_KEYWORD, "iteration-statement"); if (!token) return error_mark_node; /* Remember whether or not we are already within an iteration statement. */ in_iteration_statement_p = parser->in_iteration_statement_p; /* See what kind of keyword it is. */ keyword = token->keyword; switch (keyword) { case RID_WHILE: { tree condition; /* Begin the while-statement. */ statement = begin_while_stmt (); /* Look for the `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Parse the condition. */ condition = cp_parser_condition (parser); finish_while_stmt_cond (condition, statement); /* Look for the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Parse the dependent statement. */ parser->in_iteration_statement_p = true; cp_parser_already_scoped_statement (parser); parser->in_iteration_statement_p = in_iteration_statement_p; /* We're done with the while-statement. */ finish_while_stmt (statement); } break; case RID_DO: { tree expression; /* Begin the do-statement. */ statement = begin_do_stmt (); /* Parse the body of the do-statement. */ parser->in_iteration_statement_p = true; cp_parser_implicitly_scoped_statement (parser); parser->in_iteration_statement_p = in_iteration_statement_p; finish_do_body (statement); /* Look for the `while' keyword. */ cp_parser_require_keyword (parser, RID_WHILE, "`while'"); /* Look for the `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Parse the expression. */ expression = cp_parser_expression (parser); /* We're done with the do-statement. */ finish_do_stmt (expression, statement); /* Look for the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Look for the `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); } break; case RID_FOR: { tree condition = NULL_TREE; tree expression = NULL_TREE; /* Begin the for-statement. */ statement = begin_for_stmt (); /* Look for the `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Parse the initialization. */ cp_parser_for_init_statement (parser); finish_for_init_stmt (statement); /* If there's a condition, process it. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) condition = cp_parser_condition (parser); finish_for_cond (condition, statement); /* Look for the `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); /* If there's an expression, process it. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN)) expression = cp_parser_expression (parser); finish_for_expr (expression, statement); /* Look for the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Parse the body of the for-statement. */ parser->in_iteration_statement_p = true; cp_parser_already_scoped_statement (parser); parser->in_iteration_statement_p = in_iteration_statement_p; /* We're done with the for-statement. */ finish_for_stmt (statement); } break; default: cp_parser_error (parser, "expected iteration-statement"); statement = error_mark_node; break; } return statement; } /* Parse a for-init-statement. for-init-statement: expression-statement simple-declaration */ static void cp_parser_for_init_statement (cp_parser* parser) { /* If the next token is a `;', then we have an empty expression-statement. Grammatically, this is also a simple-declaration, but an invalid one, because it does not declare anything. Therefore, if we did not handle this case specially, we would issue an error message about an invalid declaration. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) { /* We're going to speculatively look for a declaration, falling back to an expression, if necessary. */ cp_parser_parse_tentatively (parser); /* Parse the declaration. */ cp_parser_simple_declaration (parser, /*function_definition_allowed_p=*/false); /* If the tentative parse failed, then we shall need to look for an expression-statement. */ if (cp_parser_parse_definitely (parser)) return; } cp_parser_expression_statement (parser, false); } /* Parse a jump-statement. jump-statement: break ; continue ; return expression [opt] ; goto identifier ; GNU extension: jump-statement: goto * expression ; Returns the new BREAK_STMT, CONTINUE_STMT, RETURN_STMT, or GOTO_STMT. */ static tree cp_parser_jump_statement (cp_parser* parser) { tree statement = error_mark_node; cp_token *token; enum rid keyword; /* Peek at the next token. */ token = cp_parser_require (parser, CPP_KEYWORD, "jump-statement"); if (!token) return error_mark_node; /* See what kind of keyword it is. */ keyword = token->keyword; switch (keyword) { case RID_BREAK: if (!parser->in_switch_statement_p && !parser->in_iteration_statement_p) { error ("break statement not within loop or switch"); statement = error_mark_node; } else statement = finish_break_stmt (); cp_parser_require (parser, CPP_SEMICOLON, "`;'"); break; case RID_CONTINUE: if (!parser->in_iteration_statement_p) { error ("continue statement not within a loop"); statement = error_mark_node; } else statement = finish_continue_stmt (); cp_parser_require (parser, CPP_SEMICOLON, "`;'"); break; case RID_RETURN: { tree expr; /* If the next token is a `;', then there is no expression. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) expr = cp_parser_expression (parser); else expr = NULL_TREE; /* Build the return-statement. */ statement = finish_return_stmt (expr); /* Look for the final `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); } break; case RID_GOTO: /* Create the goto-statement. */ if (cp_lexer_next_token_is (parser->lexer, CPP_MULT)) { /* Issue a warning about this use of a GNU extension. */ if (pedantic) pedwarn ("ISO C++ forbids computed gotos"); /* Consume the '*' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the dependent expression. */ finish_goto_stmt (cp_parser_expression (parser)); } else finish_goto_stmt (cp_parser_identifier (parser)); /* Look for the final `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); break; default: cp_parser_error (parser, "expected jump-statement"); break; } return statement; } /* Parse a declaration-statement. declaration-statement: block-declaration */ static void cp_parser_declaration_statement (cp_parser* parser) { /* Parse the block-declaration. */ cp_parser_block_declaration (parser, /*statement_p=*/true); /* Finish off the statement. */ finish_stmt (); } /* Some dependent statements (like `if (cond) statement'), are implicitly in their own scope. In other words, if the statement is a single statement (as opposed to a compound-statement), it is none-the-less treated as if it were enclosed in braces. Any declarations appearing in the dependent statement are out of scope after control passes that point. This function parses a statement, but ensures that is in its own scope, even if it is not a compound-statement. Returns the new statement. */ static tree cp_parser_implicitly_scoped_statement (cp_parser* parser) { tree statement; /* If the token is not a `{', then we must take special action. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_BRACE)) { /* Create a compound-statement. */ statement = begin_compound_stmt (/*has_no_scope=*/false); /* Parse the dependent-statement. */ cp_parser_statement (parser, false); /* Finish the dummy compound-statement. */ finish_compound_stmt (statement); } /* Otherwise, we simply parse the statement directly. */ else statement = cp_parser_compound_statement (parser, false); /* Return the statement. */ return statement; } /* For some dependent statements (like `while (cond) statement'), we have already created a scope. Therefore, even if the dependent statement is a compound-statement, we do not want to create another scope. */ static void cp_parser_already_scoped_statement (cp_parser* parser) { /* If the token is not a `{', then we must take special action. */ if (cp_lexer_next_token_is_not(parser->lexer, CPP_OPEN_BRACE)) { tree statement; /* Create a compound-statement. */ statement = begin_compound_stmt (/*has_no_scope=*/true); /* Parse the dependent-statement. */ cp_parser_statement (parser, false); /* Finish the dummy compound-statement. */ finish_compound_stmt (statement); } /* Otherwise, we simply parse the statement directly. */ else cp_parser_statement (parser, false); } /* Declarations [gram.dcl.dcl] */ /* Parse an optional declaration-sequence. declaration-seq: declaration declaration-seq declaration */ static void cp_parser_declaration_seq_opt (cp_parser* parser) { while (true) { cp_token *token; token = cp_lexer_peek_token (parser->lexer); if (token->type == CPP_CLOSE_BRACE || token->type == CPP_EOF) break; if (token->type == CPP_SEMICOLON) { /* A declaration consisting of a single semicolon is invalid. Allow it unless we're being pedantic. */ if (pedantic && !in_system_header) pedwarn ("extra `;'"); cp_lexer_consume_token (parser->lexer); continue; } /* The C lexer modifies PENDING_LANG_CHANGE when it wants the parser to enter or exit implicit `extern "C"' blocks. */ while (pending_lang_change > 0) { push_lang_context (lang_name_c); --pending_lang_change; } while (pending_lang_change < 0) { pop_lang_context (); ++pending_lang_change; } /* Parse the declaration itself. */ cp_parser_declaration (parser); } } /* Parse a declaration. declaration: block-declaration function-definition template-declaration explicit-instantiation explicit-specialization linkage-specification namespace-definition GNU extension: declaration: __extension__ declaration */ static void cp_parser_declaration (cp_parser* parser) { cp_token token1; cp_token token2; int saved_pedantic; /* Check for the `__extension__' keyword. */ if (cp_parser_extension_opt (parser, &saved_pedantic)) { /* Parse the qualified declaration. */ cp_parser_declaration (parser); /* Restore the PEDANTIC flag. */ pedantic = saved_pedantic; return; } /* Try to figure out what kind of declaration is present. */ token1 = *cp_lexer_peek_token (parser->lexer); if (token1.type != CPP_EOF) token2 = *cp_lexer_peek_nth_token (parser->lexer, 2); /* If the next token is `extern' and the following token is a string literal, then we have a linkage specification. */ if (token1.keyword == RID_EXTERN && cp_parser_is_string_literal (&token2)) cp_parser_linkage_specification (parser); /* If the next token is `template', then we have either a template declaration, an explicit instantiation, or an explicit specialization. */ else if (token1.keyword == RID_TEMPLATE) { /* `template <>' indicates a template specialization. */ if (token2.type == CPP_LESS && cp_lexer_peek_nth_token (parser->lexer, 3)->type == CPP_GREATER) cp_parser_explicit_specialization (parser); /* `template <' indicates a template declaration. */ else if (token2.type == CPP_LESS) cp_parser_template_declaration (parser, /*member_p=*/false); /* Anything else must be an explicit instantiation. */ else cp_parser_explicit_instantiation (parser); } /* If the next token is `export', then we have a template declaration. */ else if (token1.keyword == RID_EXPORT) cp_parser_template_declaration (parser, /*member_p=*/false); /* If the next token is `extern', 'static' or 'inline' and the one after that is `template', we have a GNU extended explicit instantiation directive. */ else if (cp_parser_allow_gnu_extensions_p (parser) && (token1.keyword == RID_EXTERN || token1.keyword == RID_STATIC || token1.keyword == RID_INLINE) && token2.keyword == RID_TEMPLATE) cp_parser_explicit_instantiation (parser); /* If the next token is `namespace', check for a named or unnamed namespace definition. */ else if (token1.keyword == RID_NAMESPACE && (/* A named namespace definition. */ (token2.type == CPP_NAME && (cp_lexer_peek_nth_token (parser->lexer, 3)->type == CPP_OPEN_BRACE)) /* An unnamed namespace definition. */ || token2.type == CPP_OPEN_BRACE)) cp_parser_namespace_definition (parser); /* We must have either a block declaration or a function definition. */ else /* Try to parse a block-declaration, or a function-definition. */ cp_parser_block_declaration (parser, /*statement_p=*/false); } /* Parse a block-declaration. block-declaration: simple-declaration asm-definition namespace-alias-definition using-declaration using-directive GNU Extension: block-declaration: __extension__ block-declaration label-declaration If STATEMENT_P is TRUE, then this block-declaration is occurring as part of a declaration-statement. */ static void cp_parser_block_declaration (cp_parser *parser, bool statement_p) { cp_token *token1; int saved_pedantic; /* Check for the `__extension__' keyword. */ if (cp_parser_extension_opt (parser, &saved_pedantic)) { /* Parse the qualified declaration. */ cp_parser_block_declaration (parser, statement_p); /* Restore the PEDANTIC flag. */ pedantic = saved_pedantic; return; } /* Peek at the next token to figure out which kind of declaration is present. */ token1 = cp_lexer_peek_token (parser->lexer); /* If the next keyword is `asm', we have an asm-definition. */ if (token1->keyword == RID_ASM) { if (statement_p) cp_parser_commit_to_tentative_parse (parser); cp_parser_asm_definition (parser); } /* If the next keyword is `namespace', we have a namespace-alias-definition. */ else if (token1->keyword == RID_NAMESPACE) cp_parser_namespace_alias_definition (parser); /* If the next keyword is `using', we have either a using-declaration or a using-directive. */ else if (token1->keyword == RID_USING) { cp_token *token2; if (statement_p) cp_parser_commit_to_tentative_parse (parser); /* If the token after `using' is `namespace', then we have a using-directive. */ token2 = cp_lexer_peek_nth_token (parser->lexer, 2); if (token2->keyword == RID_NAMESPACE) cp_parser_using_directive (parser); /* Otherwise, it's a using-declaration. */ else cp_parser_using_declaration (parser); } /* If the next keyword is `__label__' we have a label declaration. */ else if (token1->keyword == RID_LABEL) { if (statement_p) cp_parser_commit_to_tentative_parse (parser); cp_parser_label_declaration (parser); } /* Anything else must be a simple-declaration. */ else cp_parser_simple_declaration (parser, !statement_p); } /* Parse a simple-declaration. simple-declaration: decl-specifier-seq [opt] init-declarator-list [opt] ; init-declarator-list: init-declarator init-declarator-list , init-declarator If FUNCTION_DEFINITION_ALLOWED_P is TRUE, then we also recognize a function-definition as a simple-declaration. */ static void cp_parser_simple_declaration (cp_parser* parser, bool function_definition_allowed_p) { tree decl_specifiers; tree attributes; int declares_class_or_enum; bool saw_declarator; /* Defer access checks until we know what is being declared; the checks for names appearing in the decl-specifier-seq should be done as if we were in the scope of the thing being declared. */ push_deferring_access_checks (dk_deferred); /* Parse the decl-specifier-seq. We have to keep track of whether or not the decl-specifier-seq declares a named class or enumeration type, since that is the only case in which the init-declarator-list is allowed to be empty. [dcl.dcl] In a simple-declaration, the optional init-declarator-list can be omitted only when declaring a class or enumeration, that is when the decl-specifier-seq contains either a class-specifier, an elaborated-type-specifier, or an enum-specifier. */ decl_specifiers = cp_parser_decl_specifier_seq (parser, CP_PARSER_FLAGS_OPTIONAL, &attributes, &declares_class_or_enum); /* We no longer need to defer access checks. */ stop_deferring_access_checks (); /* In a block scope, a valid declaration must always have a decl-specifier-seq. By not trying to parse declarators, we can resolve the declaration/expression ambiguity more quickly. */ if (!function_definition_allowed_p && !decl_specifiers) { cp_parser_error (parser, "expected declaration"); goto done; } /* If the next two tokens are both identifiers, the code is erroneous. The usual cause of this situation is code like: T t; where "T" should name a type -- but does not. */ if (cp_parser_diagnose_invalid_type_name (parser)) { /* If parsing tentatively, we should commit; we really are looking at a declaration. */ cp_parser_commit_to_tentative_parse (parser); /* Give up. */ goto done; } /* Keep going until we hit the `;' at the end of the simple declaration. */ saw_declarator = false; while (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) { cp_token *token; bool function_definition_p; tree decl; saw_declarator = true; /* Parse the init-declarator. */ decl = cp_parser_init_declarator (parser, decl_specifiers, attributes, function_definition_allowed_p, /*member_p=*/false, declares_class_or_enum, &function_definition_p); /* If an error occurred while parsing tentatively, exit quickly. (That usually happens when in the body of a function; each statement is treated as a declaration-statement until proven otherwise.) */ if (cp_parser_error_occurred (parser)) goto done; /* Handle function definitions specially. */ if (function_definition_p) { /* If the next token is a `,', then we are probably processing something like: void f() {}, *p; which is erroneous. */ if (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)) error ("mixing declarations and function-definitions is forbidden"); /* Otherwise, we're done with the list of declarators. */ else { pop_deferring_access_checks (); return; } } /* The next token should be either a `,' or a `;'. */ token = cp_lexer_peek_token (parser->lexer); /* If it's a `,', there are more declarators to come. */ if (token->type == CPP_COMMA) cp_lexer_consume_token (parser->lexer); /* If it's a `;', we are done. */ else if (token->type == CPP_SEMICOLON) break; /* Anything else is an error. */ else { cp_parser_error (parser, "expected `,' or `;'"); /* Skip tokens until we reach the end of the statement. */ cp_parser_skip_to_end_of_statement (parser); /* If the next token is now a `;', consume it. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON)) cp_lexer_consume_token (parser->lexer); goto done; } /* After the first time around, a function-definition is not allowed -- even if it was OK at first. For example: int i, f() {} is not valid. */ function_definition_allowed_p = false; } /* Issue an error message if no declarators are present, and the decl-specifier-seq does not itself declare a class or enumeration. */ if (!saw_declarator) { if (cp_parser_declares_only_class_p (parser)) shadow_tag (decl_specifiers); /* Perform any deferred access checks. */ perform_deferred_access_checks (); } /* Consume the `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); done: pop_deferring_access_checks (); } /* Parse a decl-specifier-seq. decl-specifier-seq: decl-specifier-seq [opt] decl-specifier decl-specifier: storage-class-specifier type-specifier function-specifier friend typedef GNU Extension: decl-specifier: attributes Returns a TREE_LIST, giving the decl-specifiers in the order they appear in the source code. The TREE_VALUE of each node is the decl-specifier. For a keyword (such as `auto' or `friend'), the TREE_VALUE is simply the corresponding TREE_IDENTIFIER. For the representation of a type-specifier, see cp_parser_type_specifier. If there are attributes, they will be stored in *ATTRIBUTES, represented as described above cp_parser_attributes. If FRIEND_IS_NOT_CLASS_P is non-NULL, and the `friend' specifier appears, and the entity that will be a friend is not going to be a class, then *FRIEND_IS_NOT_CLASS_P will be set to TRUE. Note that even if *FRIEND_IS_NOT_CLASS_P is FALSE, the entity to which friendship is granted might not be a class. *DECLARES_CLASS_OR_ENUM is set to the bitwise or of the following flags: 1: one of the decl-specifiers is an elaborated-type-specifier (i.e., a type declaration) 2: one of the decl-specifiers is an enum-specifier or a class-specifier (i.e., a type definition) */ static tree cp_parser_decl_specifier_seq (cp_parser* parser, cp_parser_flags flags, tree* attributes, int* declares_class_or_enum) { tree decl_specs = NULL_TREE; bool friend_p = false; bool constructor_possible_p = !parser->in_declarator_p; /* Assume no class or enumeration type is declared. */ *declares_class_or_enum = 0; /* Assume there are no attributes. */ *attributes = NULL_TREE; /* Keep reading specifiers until there are no more to read. */ while (true) { tree decl_spec = NULL_TREE; bool constructor_p; cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Handle attributes. */ if (token->keyword == RID_ATTRIBUTE) { /* Parse the attributes. */ decl_spec = cp_parser_attributes_opt (parser); /* Add them to the list. */ *attributes = chainon (*attributes, decl_spec); continue; } /* If the next token is an appropriate keyword, we can simply add it to the list. */ switch (token->keyword) { case RID_FRIEND: /* decl-specifier: friend */ if (friend_p) error ("duplicate `friend'"); else friend_p = true; /* The representation of the specifier is simply the appropriate TREE_IDENTIFIER node. */ decl_spec = token->value; /* Consume the token. */ cp_lexer_consume_token (parser->lexer); break; /* function-specifier: inline virtual explicit */ case RID_INLINE: case RID_VIRTUAL: case RID_EXPLICIT: decl_spec = cp_parser_function_specifier_opt (parser); break; /* decl-specifier: typedef */ case RID_TYPEDEF: /* The representation of the specifier is simply the appropriate TREE_IDENTIFIER node. */ decl_spec = token->value; /* Consume the token. */ cp_lexer_consume_token (parser->lexer); /* A constructor declarator cannot appear in a typedef. */ constructor_possible_p = false; /* The "typedef" keyword can only occur in a declaration; we may as well commit at this point. */ cp_parser_commit_to_tentative_parse (parser); break; /* storage-class-specifier: auto register static extern mutable GNU Extension: thread */ case RID_AUTO: case RID_REGISTER: case RID_STATIC: case RID_EXTERN: case RID_MUTABLE: case RID_THREAD: decl_spec = cp_parser_storage_class_specifier_opt (parser); break; default: break; } /* Constructors are a special case. The `S' in `S()' is not a decl-specifier; it is the beginning of the declarator. */ constructor_p = (!decl_spec && constructor_possible_p && cp_parser_constructor_declarator_p (parser, friend_p)); /* If we don't have a DECL_SPEC yet, then we must be looking at a type-specifier. */ if (!decl_spec && !constructor_p) { int decl_spec_declares_class_or_enum; bool is_cv_qualifier; decl_spec = cp_parser_type_specifier (parser, flags, friend_p, /*is_declaration=*/true, &decl_spec_declares_class_or_enum, &is_cv_qualifier); *declares_class_or_enum |= decl_spec_declares_class_or_enum; /* If this type-specifier referenced a user-defined type (a typedef, class-name, etc.), then we can't allow any more such type-specifiers henceforth. [dcl.spec] The longest sequence of decl-specifiers that could possibly be a type name is taken as the decl-specifier-seq of a declaration. The sequence shall be self-consistent as described below. [dcl.type] As a general rule, at most one type-specifier is allowed in the complete decl-specifier-seq of a declaration. The only exceptions are the following: -- const or volatile can be combined with any other type-specifier. -- signed or unsigned can be combined with char, long, short, or int. -- .. Example: typedef char* Pc; void g (const int Pc); Here, Pc is *not* part of the decl-specifier seq; it's the declarator. Therefore, once we see a type-specifier (other than a cv-qualifier), we forbid any additional user-defined types. We *do* still allow things like `int int' to be considered a decl-specifier-seq, and issue the error message later. */ if (decl_spec && !is_cv_qualifier) flags |= CP_PARSER_FLAGS_NO_USER_DEFINED_TYPES; /* A constructor declarator cannot follow a type-specifier. */ if (decl_spec) constructor_possible_p = false; } /* If we still do not have a DECL_SPEC, then there are no more decl-specifiers. */ if (!decl_spec) { /* Issue an error message, unless the entire construct was optional. */ if (!(flags & CP_PARSER_FLAGS_OPTIONAL)) { cp_parser_error (parser, "expected decl specifier"); return error_mark_node; } break; } /* Add the DECL_SPEC to the list of specifiers. */ if (decl_specs == NULL || TREE_VALUE (decl_specs) != error_mark_node) decl_specs = tree_cons (NULL_TREE, decl_spec, decl_specs); /* After we see one decl-specifier, further decl-specifiers are always optional. */ flags |= CP_PARSER_FLAGS_OPTIONAL; } /* Don't allow a friend specifier with a class definition. */ if (friend_p && (*declares_class_or_enum & 2)) error ("class definition may not be declared a friend"); /* We have built up the DECL_SPECS in reverse order. Return them in the correct order. */ return nreverse (decl_specs); } /* Parse an (optional) storage-class-specifier. storage-class-specifier: auto register static extern mutable GNU Extension: storage-class-specifier: thread Returns an IDENTIFIER_NODE corresponding to the keyword used. */ static tree cp_parser_storage_class_specifier_opt (cp_parser* parser) { switch (cp_lexer_peek_token (parser->lexer)->keyword) { case RID_AUTO: case RID_REGISTER: case RID_STATIC: case RID_EXTERN: case RID_MUTABLE: case RID_THREAD: /* Consume the token. */ return cp_lexer_consume_token (parser->lexer)->value; default: return NULL_TREE; } } /* Parse an (optional) function-specifier. function-specifier: inline virtual explicit Returns an IDENTIFIER_NODE corresponding to the keyword used. */ static tree cp_parser_function_specifier_opt (cp_parser* parser) { switch (cp_lexer_peek_token (parser->lexer)->keyword) { case RID_INLINE: case RID_VIRTUAL: case RID_EXPLICIT: /* Consume the token. */ return cp_lexer_consume_token (parser->lexer)->value; default: return NULL_TREE; } } /* Parse a linkage-specification. linkage-specification: extern string-literal { declaration-seq [opt] } extern string-literal declaration */ static void cp_parser_linkage_specification (cp_parser* parser) { cp_token *token; tree linkage; /* Look for the `extern' keyword. */ cp_parser_require_keyword (parser, RID_EXTERN, "`extern'"); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's not a string-literal, then there's a problem. */ if (!cp_parser_is_string_literal (token)) { cp_parser_error (parser, "expected language-name"); return; } /* Consume the token. */ cp_lexer_consume_token (parser->lexer); /* Transform the literal into an identifier. If the literal is a wide-character string, or contains embedded NULs, then we can't handle it as the user wants. */ if (token->type == CPP_WSTRING || (strlen (TREE_STRING_POINTER (token->value)) != (size_t) (TREE_STRING_LENGTH (token->value) - 1))) { cp_parser_error (parser, "invalid linkage-specification"); /* Assume C++ linkage. */ linkage = get_identifier ("c++"); } /* If it's a simple string constant, things are easier. */ else linkage = get_identifier (TREE_STRING_POINTER (token->value)); /* We're now using the new linkage. */ push_lang_context (linkage); /* If the next token is a `{', then we're using the first production. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE)) { /* Consume the `{' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the declarations. */ cp_parser_declaration_seq_opt (parser); /* Look for the closing `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); } /* Otherwise, there's just one declaration. */ else { bool saved_in_unbraced_linkage_specification_p; saved_in_unbraced_linkage_specification_p = parser->in_unbraced_linkage_specification_p; parser->in_unbraced_linkage_specification_p = true; have_extern_spec = true; cp_parser_declaration (parser); have_extern_spec = false; parser->in_unbraced_linkage_specification_p = saved_in_unbraced_linkage_specification_p; } /* We're done with the linkage-specification. */ pop_lang_context (); } /* Special member functions [gram.special] */ /* Parse a conversion-function-id. conversion-function-id: operator conversion-type-id Returns an IDENTIFIER_NODE representing the operator. */ static tree cp_parser_conversion_function_id (cp_parser* parser) { tree type; tree saved_scope; tree saved_qualifying_scope; tree saved_object_scope; bool pop_p = false; /* Look for the `operator' token. */ if (!cp_parser_require_keyword (parser, RID_OPERATOR, "`operator'")) return error_mark_node; /* When we parse the conversion-type-id, the current scope will be reset. However, we need that information in able to look up the conversion function later, so we save it here. */ saved_scope = parser->scope; saved_qualifying_scope = parser->qualifying_scope; saved_object_scope = parser->object_scope; /* We must enter the scope of the class so that the names of entities declared within the class are available in the conversion-type-id. For example, consider: struct S { typedef int I; operator I(); }; S::operator I() { ... } In order to see that `I' is a type-name in the definition, we must be in the scope of `S'. */ if (saved_scope) pop_p = push_scope (saved_scope); /* Parse the conversion-type-id. */ type = cp_parser_conversion_type_id (parser); /* Leave the scope of the class, if any. */ if (pop_p) pop_scope (saved_scope); /* Restore the saved scope. */ parser->scope = saved_scope; parser->qualifying_scope = saved_qualifying_scope; parser->object_scope = saved_object_scope; /* If the TYPE is invalid, indicate failure. */ if (type == error_mark_node) return error_mark_node; return mangle_conv_op_name_for_type (type); } /* Parse a conversion-type-id: conversion-type-id: type-specifier-seq conversion-declarator [opt] Returns the TYPE specified. */ static tree cp_parser_conversion_type_id (cp_parser* parser) { tree attributes; tree type_specifiers; tree declarator; /* Parse the attributes. */ attributes = cp_parser_attributes_opt (parser); /* Parse the type-specifiers. */ type_specifiers = cp_parser_type_specifier_seq (parser); /* If that didn't work, stop. */ if (type_specifiers == error_mark_node) return error_mark_node; /* Parse the conversion-declarator. */ declarator = cp_parser_conversion_declarator_opt (parser); return grokdeclarator (declarator, type_specifiers, TYPENAME, /*initialized=*/0, &attributes); } /* Parse an (optional) conversion-declarator. conversion-declarator: ptr-operator conversion-declarator [opt] Returns a representation of the declarator. See cp_parser_declarator for details. */ static tree cp_parser_conversion_declarator_opt (cp_parser* parser) { enum tree_code code; tree class_type; tree cv_qualifier_seq; /* We don't know if there's a ptr-operator next, or not. */ cp_parser_parse_tentatively (parser); /* Try the ptr-operator. */ code = cp_parser_ptr_operator (parser, &class_type, &cv_qualifier_seq); /* If it worked, look for more conversion-declarators. */ if (cp_parser_parse_definitely (parser)) { tree declarator; /* Parse another optional declarator. */ declarator = cp_parser_conversion_declarator_opt (parser); /* Create the representation of the declarator. */ if (code == INDIRECT_REF) declarator = make_pointer_declarator (cv_qualifier_seq, declarator); else declarator = make_reference_declarator (cv_qualifier_seq, declarator); /* Handle the pointer-to-member case. */ if (class_type) declarator = build_nt (SCOPE_REF, class_type, declarator); return declarator; } return NULL_TREE; } /* Parse an (optional) ctor-initializer. ctor-initializer: : mem-initializer-list Returns TRUE iff the ctor-initializer was actually present. */ static bool cp_parser_ctor_initializer_opt (cp_parser* parser) { /* If the next token is not a `:', then there is no ctor-initializer. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COLON)) { /* Do default initialization of any bases and members. */ if (DECL_CONSTRUCTOR_P (current_function_decl)) finish_mem_initializers (NULL_TREE); return false; } /* Consume the `:' token. */ cp_lexer_consume_token (parser->lexer); /* And the mem-initializer-list. */ cp_parser_mem_initializer_list (parser); return true; } /* Parse a mem-initializer-list. mem-initializer-list: mem-initializer mem-initializer , mem-initializer-list */ static void cp_parser_mem_initializer_list (cp_parser* parser) { tree mem_initializer_list = NULL_TREE; /* Let the semantic analysis code know that we are starting the mem-initializer-list. */ if (!DECL_CONSTRUCTOR_P (current_function_decl)) error ("only constructors take base initializers"); /* Loop through the list. */ while (true) { tree mem_initializer; /* Parse the mem-initializer. */ mem_initializer = cp_parser_mem_initializer (parser); /* Add it to the list, unless it was erroneous. */ if (mem_initializer) { TREE_CHAIN (mem_initializer) = mem_initializer_list; mem_initializer_list = mem_initializer; } /* If the next token is not a `,', we're done. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) break; /* Consume the `,' token. */ cp_lexer_consume_token (parser->lexer); } /* Perform semantic analysis. */ if (DECL_CONSTRUCTOR_P (current_function_decl)) finish_mem_initializers (mem_initializer_list); } /* Parse a mem-initializer. mem-initializer: mem-initializer-id ( expression-list [opt] ) GNU extension: mem-initializer: ( expression-list [opt] ) Returns a TREE_LIST. The TREE_PURPOSE is the TYPE (for a base class) or FIELD_DECL (for a non-static data member) to initialize; the TREE_VALUE is the expression-list. */ static tree cp_parser_mem_initializer (cp_parser* parser) { tree mem_initializer_id; tree expression_list; tree member; /* Find out what is being initialized. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN)) { pedwarn ("anachronistic old-style base class initializer"); mem_initializer_id = NULL_TREE; } else mem_initializer_id = cp_parser_mem_initializer_id (parser); member = expand_member_init (mem_initializer_id); if (member && !DECL_P (member)) in_base_initializer = 1; expression_list = cp_parser_parenthesized_expression_list (parser, false, /*non_constant_p=*/NULL); if (!expression_list) expression_list = void_type_node; in_base_initializer = 0; return member ? build_tree_list (member, expression_list) : NULL_TREE; } /* Parse a mem-initializer-id. mem-initializer-id: :: [opt] nested-name-specifier [opt] class-name identifier Returns a TYPE indicating the class to be initializer for the first production. Returns an IDENTIFIER_NODE indicating the data member to be initialized for the second production. */ static tree cp_parser_mem_initializer_id (cp_parser* parser) { bool global_scope_p; bool nested_name_specifier_p; bool template_p = false; tree id; /* `typename' is not allowed in this context ([temp.res]). */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_TYPENAME)) { error ("keyword `typename' not allowed in this context (a qualified " "member initializer is implicitly a type)"); cp_lexer_consume_token (parser->lexer); } /* Look for the optional `::' operator. */ global_scope_p = (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false) != NULL_TREE); /* Look for the optional nested-name-specifier. The simplest way to implement: [temp.res] The keyword `typename' is not permitted in a base-specifier or mem-initializer; in these contexts a qualified name that depends on a template-parameter is implicitly assumed to be a type name. is to assume that we have seen the `typename' keyword at this point. */ nested_name_specifier_p = (cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/true, /*check_dependency_p=*/true, /*type_p=*/true, /*is_declaration=*/true) != NULL_TREE); if (nested_name_specifier_p) template_p = cp_parser_optional_template_keyword (parser); /* If there is a `::' operator or a nested-name-specifier, then we are definitely looking for a class-name. */ if (global_scope_p || nested_name_specifier_p) return cp_parser_class_name (parser, /*typename_keyword_p=*/true, /*template_keyword_p=*/template_p, /*type_p=*/false, /*check_dependency_p=*/true, /*class_head_p=*/false, /*is_declaration=*/true); /* Otherwise, we could also be looking for an ordinary identifier. */ cp_parser_parse_tentatively (parser); /* Try a class-name. */ id = cp_parser_class_name (parser, /*typename_keyword_p=*/true, /*template_keyword_p=*/false, /*type_p=*/false, /*check_dependency_p=*/true, /*class_head_p=*/false, /*is_declaration=*/true); /* If we found one, we're done. */ if (cp_parser_parse_definitely (parser)) return id; /* Otherwise, look for an ordinary identifier. */ return cp_parser_identifier (parser); } /* Overloading [gram.over] */ /* Parse an operator-function-id. operator-function-id: operator operator Returns an IDENTIFIER_NODE for the operator which is a human-readable spelling of the identifier, e.g., `operator +'. */ static tree cp_parser_operator_function_id (cp_parser* parser) { /* Look for the `operator' keyword. */ if (!cp_parser_require_keyword (parser, RID_OPERATOR, "`operator'")) return error_mark_node; /* And then the name of the operator itself. */ return cp_parser_operator (parser); } /* Parse an operator. operator: new delete new[] delete[] + - * / % ^ & | ~ ! = < > += -= *= /= %= ^= &= |= << >> >>= <<= == != <= >= && || ++ -- , ->* -> () [] GNU Extensions: operator: ? ?= Returns an IDENTIFIER_NODE for the operator which is a human-readable spelling of the identifier, e.g., `operator +'. */ static tree cp_parser_operator (cp_parser* parser) { tree id = NULL_TREE; cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Figure out which operator we have. */ switch (token->type) { case CPP_KEYWORD: { enum tree_code op; /* The keyword should be either `new' or `delete'. */ if (token->keyword == RID_NEW) op = NEW_EXPR; else if (token->keyword == RID_DELETE) op = DELETE_EXPR; else break; /* Consume the `new' or `delete' token. */ cp_lexer_consume_token (parser->lexer); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's a `[' token then this is the array variant of the operator. */ if (token->type == CPP_OPEN_SQUARE) { /* Consume the `[' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the `]' token. */ cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'"); id = ansi_opname (op == NEW_EXPR ? VEC_NEW_EXPR : VEC_DELETE_EXPR); } /* Otherwise, we have the non-array variant. */ else id = ansi_opname (op); return id; } case CPP_PLUS: id = ansi_opname (PLUS_EXPR); break; case CPP_MINUS: id = ansi_opname (MINUS_EXPR); break; case CPP_MULT: id = ansi_opname (MULT_EXPR); break; case CPP_DIV: id = ansi_opname (TRUNC_DIV_EXPR); break; case CPP_MOD: id = ansi_opname (TRUNC_MOD_EXPR); break; case CPP_XOR: id = ansi_opname (BIT_XOR_EXPR); break; case CPP_AND: id = ansi_opname (BIT_AND_EXPR); break; case CPP_OR: id = ansi_opname (BIT_IOR_EXPR); break; case CPP_COMPL: id = ansi_opname (BIT_NOT_EXPR); break; case CPP_NOT: id = ansi_opname (TRUTH_NOT_EXPR); break; case CPP_EQ: id = ansi_assopname (NOP_EXPR); break; case CPP_LESS: id = ansi_opname (LT_EXPR); break; case CPP_GREATER: id = ansi_opname (GT_EXPR); break; case CPP_PLUS_EQ: id = ansi_assopname (PLUS_EXPR); break; case CPP_MINUS_EQ: id = ansi_assopname (MINUS_EXPR); break; case CPP_MULT_EQ: id = ansi_assopname (MULT_EXPR); break; case CPP_DIV_EQ: id = ansi_assopname (TRUNC_DIV_EXPR); break; case CPP_MOD_EQ: id = ansi_assopname (TRUNC_MOD_EXPR); break; case CPP_XOR_EQ: id = ansi_assopname (BIT_XOR_EXPR); break; case CPP_AND_EQ: id = ansi_assopname (BIT_AND_EXPR); break; case CPP_OR_EQ: id = ansi_assopname (BIT_IOR_EXPR); break; case CPP_LSHIFT: id = ansi_opname (LSHIFT_EXPR); break; case CPP_RSHIFT: id = ansi_opname (RSHIFT_EXPR); break; case CPP_LSHIFT_EQ: id = ansi_assopname (LSHIFT_EXPR); break; case CPP_RSHIFT_EQ: id = ansi_assopname (RSHIFT_EXPR); break; case CPP_EQ_EQ: id = ansi_opname (EQ_EXPR); break; case CPP_NOT_EQ: id = ansi_opname (NE_EXPR); break; case CPP_LESS_EQ: id = ansi_opname (LE_EXPR); break; case CPP_GREATER_EQ: id = ansi_opname (GE_EXPR); break; case CPP_AND_AND: id = ansi_opname (TRUTH_ANDIF_EXPR); break; case CPP_OR_OR: id = ansi_opname (TRUTH_ORIF_EXPR); break; case CPP_PLUS_PLUS: id = ansi_opname (POSTINCREMENT_EXPR); break; case CPP_MINUS_MINUS: id = ansi_opname (PREDECREMENT_EXPR); break; case CPP_COMMA: id = ansi_opname (COMPOUND_EXPR); break; case CPP_DEREF_STAR: id = ansi_opname (MEMBER_REF); break; case CPP_DEREF: id = ansi_opname (COMPONENT_REF); break; case CPP_OPEN_PAREN: /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* Look for the matching `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); return ansi_opname (CALL_EXPR); case CPP_OPEN_SQUARE: /* Consume the `['. */ cp_lexer_consume_token (parser->lexer); /* Look for the matching `]'. */ cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'"); return ansi_opname (ARRAY_REF); /* Extensions. */ case CPP_MIN: id = ansi_opname (MIN_EXPR); break; case CPP_MAX: id = ansi_opname (MAX_EXPR); break; case CPP_MIN_EQ: id = ansi_assopname (MIN_EXPR); break; case CPP_MAX_EQ: id = ansi_assopname (MAX_EXPR); break; default: /* Anything else is an error. */ break; } /* If we have selected an identifier, we need to consume the operator token. */ if (id) cp_lexer_consume_token (parser->lexer); /* Otherwise, no valid operator name was present. */ else { cp_parser_error (parser, "expected operator"); id = error_mark_node; } return id; } /* Parse a template-declaration. template-declaration: export [opt] template < template-parameter-list > declaration If MEMBER_P is TRUE, this template-declaration occurs within a class-specifier. The grammar rule given by the standard isn't correct. What is really meant is: template-declaration: export [opt] template-parameter-list-seq decl-specifier-seq [opt] init-declarator [opt] ; export [opt] template-parameter-list-seq function-definition template-parameter-list-seq: template-parameter-list-seq [opt] template < template-parameter-list > */ static void cp_parser_template_declaration (cp_parser* parser, bool member_p) { /* Check for `export'. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_EXPORT)) { /* Consume the `export' token. */ cp_lexer_consume_token (parser->lexer); /* Warn that we do not support `export'. */ warning ("keyword `export' not implemented, and will be ignored"); } cp_parser_template_declaration_after_export (parser, member_p); } /* Parse a template-parameter-list. template-parameter-list: template-parameter template-parameter-list , template-parameter Returns a TREE_LIST. Each node represents a template parameter. The nodes are connected via their TREE_CHAINs. */ static tree cp_parser_template_parameter_list (cp_parser* parser) { tree parameter_list = NULL_TREE; while (true) { tree parameter; cp_token *token; /* Parse the template-parameter. */ parameter = cp_parser_template_parameter (parser); /* Add it to the list. */ parameter_list = process_template_parm (parameter_list, parameter); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's not a `,', we're done. */ if (token->type != CPP_COMMA) break; /* Otherwise, consume the `,' token. */ cp_lexer_consume_token (parser->lexer); } return parameter_list; } /* Parse a template-parameter. template-parameter: type-parameter parameter-declaration Returns a TREE_LIST. The TREE_VALUE represents the parameter. The TREE_PURPOSE is the default value, if any. */ static tree cp_parser_template_parameter (cp_parser* parser) { cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it is `class' or `template', we have a type-parameter. */ if (token->keyword == RID_TEMPLATE) return cp_parser_type_parameter (parser); /* If it is `class' or `typename' we do not know yet whether it is a type parameter or a non-type parameter. Consider: template ... or: template ... Here, the first parameter is a type parameter, and the second is a non-type parameter. We can tell by looking at the token after the identifier -- if it is a `,', `=', or `>' then we have a type parameter. */ if (token->keyword == RID_TYPENAME || token->keyword == RID_CLASS) { /* Peek at the token after `class' or `typename'. */ token = cp_lexer_peek_nth_token (parser->lexer, 2); /* If it's an identifier, skip it. */ if (token->type == CPP_NAME) token = cp_lexer_peek_nth_token (parser->lexer, 3); /* Now, see if the token looks like the end of a template parameter. */ if (token->type == CPP_COMMA || token->type == CPP_EQ || token->type == CPP_GREATER) return cp_parser_type_parameter (parser); } /* Otherwise, it is a non-type parameter. [temp.param] When parsing a default template-argument for a non-type template-parameter, the first non-nested `>' is taken as the end of the template parameter-list rather than a greater-than operator. */ return cp_parser_parameter_declaration (parser, /*template_parm_p=*/true, /*parenthesized_p=*/NULL); } /* Parse a type-parameter. type-parameter: class identifier [opt] class identifier [opt] = type-id typename identifier [opt] typename identifier [opt] = type-id template < template-parameter-list > class identifier [opt] template < template-parameter-list > class identifier [opt] = id-expression Returns a TREE_LIST. The TREE_VALUE is itself a TREE_LIST. The TREE_PURPOSE is the default-argument, if any. The TREE_VALUE is the declaration of the parameter. */ static tree cp_parser_type_parameter (cp_parser* parser) { cp_token *token; tree parameter; /* Look for a keyword to tell us what kind of parameter this is. */ token = cp_parser_require (parser, CPP_KEYWORD, "`class', `typename', or `template'"); if (!token) return error_mark_node; switch (token->keyword) { case RID_CLASS: case RID_TYPENAME: { tree identifier; tree default_argument; /* If the next token is an identifier, then it names the parameter. */ if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)) identifier = cp_parser_identifier (parser); else identifier = NULL_TREE; /* Create the parameter. */ parameter = finish_template_type_parm (class_type_node, identifier); /* If the next token is an `=', we have a default argument. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EQ)) { /* Consume the `=' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the default-argument. */ default_argument = cp_parser_type_id (parser); } else default_argument = NULL_TREE; /* Create the combined representation of the parameter and the default argument. */ parameter = build_tree_list (default_argument, parameter); } break; case RID_TEMPLATE: { tree parameter_list; tree identifier; tree default_argument; /* Look for the `<'. */ cp_parser_require (parser, CPP_LESS, "`<'"); /* Parse the template-parameter-list. */ begin_template_parm_list (); parameter_list = cp_parser_template_parameter_list (parser); parameter_list = end_template_parm_list (parameter_list); /* Look for the `>'. */ cp_parser_require (parser, CPP_GREATER, "`>'"); /* Look for the `class' keyword. */ cp_parser_require_keyword (parser, RID_CLASS, "`class'"); /* If the next token is an `=', then there is a default-argument. If the next token is a `>', we are at the end of the parameter-list. If the next token is a `,', then we are at the end of this parameter. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_EQ) && cp_lexer_next_token_is_not (parser->lexer, CPP_GREATER) && cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) identifier = cp_parser_identifier (parser); else identifier = NULL_TREE; /* Create the template parameter. */ parameter = finish_template_template_parm (class_type_node, identifier); /* If the next token is an `=', then there is a default-argument. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EQ)) { bool is_template; /* Consume the `='. */ cp_lexer_consume_token (parser->lexer); /* Parse the id-expression. */ default_argument = cp_parser_id_expression (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, /*template_p=*/&is_template, /*declarator_p=*/false); if (TREE_CODE (default_argument) == TYPE_DECL) /* If the id-expression was a template-id that refers to a template-class, we already have the declaration here, so no further lookup is needed. */ ; else /* Look up the name. */ default_argument = cp_parser_lookup_name (parser, default_argument, /*is_type=*/false, /*is_template=*/is_template, /*is_namespace=*/false, /*check_dependency=*/true); /* See if the default argument is valid. */ default_argument = check_template_template_default_arg (default_argument); } else default_argument = NULL_TREE; /* Create the combined representation of the parameter and the default argument. */ parameter = build_tree_list (default_argument, parameter); } break; default: /* Anything else is an error. */ cp_parser_error (parser, "expected `class', `typename', or `template'"); parameter = error_mark_node; } return parameter; } /* Parse a template-id. template-id: template-name < template-argument-list [opt] > If TEMPLATE_KEYWORD_P is TRUE, then we have just seen the `template' keyword. In this case, a TEMPLATE_ID_EXPR will be returned. Otherwise, if the template-name names a function, or set of functions, returns a TEMPLATE_ID_EXPR. If the template-name names a class, returns a TYPE_DECL for the specialization. If CHECK_DEPENDENCY_P is FALSE, names are looked up in uninstantiated templates. */ static tree cp_parser_template_id (cp_parser *parser, bool template_keyword_p, bool check_dependency_p, bool is_declaration) { tree template; tree arguments; tree template_id; ptrdiff_t start_of_id; tree access_check = NULL_TREE; cp_token *next_token, *next_token_2; bool is_identifier; /* If the next token corresponds to a template-id, there is no need to reparse it. */ next_token = cp_lexer_peek_token (parser->lexer); if (next_token->type == CPP_TEMPLATE_ID) { tree value; tree check; /* Get the stored value. */ value = cp_lexer_consume_token (parser->lexer)->value; /* Perform any access checks that were deferred. */ for (check = TREE_PURPOSE (value); check; check = TREE_CHAIN (check)) perform_or_defer_access_check (TREE_PURPOSE (check), TREE_VALUE (check)); /* Return the stored value. */ return TREE_VALUE (value); } /* Avoid performing name lookup if there is no possibility of finding a template-id. */ if ((next_token->type != CPP_NAME && next_token->keyword != RID_OPERATOR) || (next_token->type == CPP_NAME && !cp_parser_nth_token_starts_template_argument_list_p (parser, 2))) { cp_parser_error (parser, "expected template-id"); return error_mark_node; } /* Remember where the template-id starts. */ if (cp_parser_parsing_tentatively (parser) && !cp_parser_committed_to_tentative_parse (parser)) { next_token = cp_lexer_peek_token (parser->lexer); start_of_id = cp_lexer_token_difference (parser->lexer, parser->lexer->first_token, next_token); } else start_of_id = -1; push_deferring_access_checks (dk_deferred); /* Parse the template-name. */ is_identifier = false; template = cp_parser_template_name (parser, template_keyword_p, check_dependency_p, is_declaration, &is_identifier); if (template == error_mark_node || is_identifier) { pop_deferring_access_checks (); return template; } /* If we find the sequence `[:' after a template-name, it's probably a digraph-typo for `< ::'. Substitute the tokens and check if we can parse correctly the argument list. */ next_token = cp_lexer_peek_nth_token (parser->lexer, 1); next_token_2 = cp_lexer_peek_nth_token (parser->lexer, 2); if (next_token->type == CPP_OPEN_SQUARE && next_token->flags & DIGRAPH && next_token_2->type == CPP_COLON && !(next_token_2->flags & PREV_WHITE)) { cp_parser_parse_tentatively (parser); /* Change `:' into `::'. */ next_token_2->type = CPP_SCOPE; /* Consume the first token (CPP_OPEN_SQUARE - which we pretend it is CPP_LESS. */ cp_lexer_consume_token (parser->lexer); /* Parse the arguments. */ arguments = cp_parser_enclosed_template_argument_list (parser); if (!cp_parser_parse_definitely (parser)) { /* If we couldn't parse an argument list, then we revert our changes and return simply an error. Maybe this is not a template-id after all. */ next_token_2->type = CPP_COLON; cp_parser_error (parser, "expected `<'"); pop_deferring_access_checks (); return error_mark_node; } /* Otherwise, emit an error about the invalid digraph, but continue parsing because we got our argument list. */ pedwarn ("`<::' cannot begin a template-argument list"); inform ("`<:' is an alternate spelling for `['. Insert whitespace " "between `<' and `::'"); if (!flag_permissive) { static bool hint; if (!hint) { inform ("(if you use `-fpermissive' G++ will accept your code)"); hint = true; } } } else { /* Look for the `<' that starts the template-argument-list. */ if (!cp_parser_require (parser, CPP_LESS, "`<'")) { pop_deferring_access_checks (); return error_mark_node; } /* Parse the arguments. */ arguments = cp_parser_enclosed_template_argument_list (parser); } /* Build a representation of the specialization. */ if (TREE_CODE (template) == IDENTIFIER_NODE) template_id = build_min_nt (TEMPLATE_ID_EXPR, template, arguments); else if (DECL_CLASS_TEMPLATE_P (template) || DECL_TEMPLATE_TEMPLATE_PARM_P (template)) template_id = finish_template_type (template, arguments, cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)); else { /* If it's not a class-template or a template-template, it should be a function-template. */ my_friendly_assert ((DECL_FUNCTION_TEMPLATE_P (template) || TREE_CODE (template) == OVERLOAD || BASELINK_P (template)), 20010716); template_id = lookup_template_function (template, arguments); } /* Retrieve any deferred checks. Do not pop this access checks yet so the memory will not be reclaimed during token replacing below. */ access_check = get_deferred_access_checks (); /* If parsing tentatively, replace the sequence of tokens that makes up the template-id with a CPP_TEMPLATE_ID token. That way, should we re-parse the token stream, we will not have to repeat the effort required to do the parse, nor will we issue duplicate error messages about problems during instantiation of the template. */ if (start_of_id >= 0) { cp_token *token; /* Find the token that corresponds to the start of the template-id. */ token = cp_lexer_advance_token (parser->lexer, parser->lexer->first_token, start_of_id); /* Reset the contents of the START_OF_ID token. */ token->type = CPP_TEMPLATE_ID; token->value = build_tree_list (access_check, template_id); token->keyword = RID_MAX; /* Purge all subsequent tokens. */ cp_lexer_purge_tokens_after (parser->lexer, token); } pop_deferring_access_checks (); return template_id; } /* Parse a template-name. template-name: identifier The standard should actually say: template-name: identifier operator-function-id A defect report has been filed about this issue. A conversion-function-id cannot be a template name because they cannot be part of a template-id. In fact, looking at this code: a.operator K() the conversion-function-id is "operator K", and K is a type-id. It is impossible to call a templated conversion-function-id with an explicit argument list, since the only allowed template parameter is the type to which it is converting. If TEMPLATE_KEYWORD_P is true, then we have just seen the `template' keyword, in a construction like: T::template f<3>() In that case `f' is taken to be a template-name, even though there is no way of knowing for sure. Returns the TEMPLATE_DECL for the template, or an OVERLOAD if the name refers to a set of overloaded functions, at least one of which is a template, or an IDENTIFIER_NODE with the name of the template, if TEMPLATE_KEYWORD_P is true. If CHECK_DEPENDENCY_P is FALSE, names are looked up inside uninstantiated templates. */ static tree cp_parser_template_name (cp_parser* parser, bool template_keyword_p, bool check_dependency_p, bool is_declaration, bool *is_identifier) { tree identifier; tree decl; tree fns; /* If the next token is `operator', then we have either an operator-function-id or a conversion-function-id. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_OPERATOR)) { /* We don't know whether we're looking at an operator-function-id or a conversion-function-id. */ cp_parser_parse_tentatively (parser); /* Try an operator-function-id. */ identifier = cp_parser_operator_function_id (parser); /* If that didn't work, try a conversion-function-id. */ if (!cp_parser_parse_definitely (parser)) { cp_parser_error (parser, "expected template-name"); return error_mark_node; } } /* Look for the identifier. */ else identifier = cp_parser_identifier (parser); /* If we didn't find an identifier, we don't have a template-id. */ if (identifier == error_mark_node) return error_mark_node; /* If the name immediately followed the `template' keyword, then it is a template-name. However, if the next token is not `<', then we do not treat it as a template-name, since it is not being used as part of a template-id. This enables us to handle constructs like: template struct S { S(); }; template S::S(); correctly. We would treat `S' as a template -- if it were `S' -- but we do not if there is no `<'. */ if (processing_template_decl && cp_parser_nth_token_starts_template_argument_list_p (parser, 1)) { /* In a declaration, in a dependent context, we pretend that the "template" keyword was present in order to improve error recovery. For example, given: template void f(T::X); we want to treat "X" as a template-id. */ if (is_declaration && !template_keyword_p && parser->scope && TYPE_P (parser->scope) && dependent_type_p (parser->scope) /* Do not do this for dtors (or ctors), since they never need the template keyword before their name. */ && !constructor_name_p (identifier, parser->scope)) { ptrdiff_t start; cp_token* token; /* Explain what went wrong. */ error ("non-template `%D' used as template", identifier); inform ("use `%T::template %D' to indicate that it is a template", parser->scope, identifier); /* If parsing tentatively, find the location of the "<" token. */ if (cp_parser_parsing_tentatively (parser) && !cp_parser_committed_to_tentative_parse (parser)) { cp_parser_simulate_error (parser); token = cp_lexer_peek_token (parser->lexer); token = cp_lexer_prev_token (parser->lexer, token); start = cp_lexer_token_difference (parser->lexer, parser->lexer->first_token, token); } else start = -1; /* Parse the template arguments so that we can issue error messages about them. */ cp_lexer_consume_token (parser->lexer); cp_parser_enclosed_template_argument_list (parser); /* Skip tokens until we find a good place from which to continue parsing. */ cp_parser_skip_to_closing_parenthesis (parser, /*recovering=*/true, /*or_comma=*/true, /*consume_paren=*/false); /* If parsing tentatively, permanently remove the template argument list. That will prevent duplicate error messages from being issued about the missing "template" keyword. */ if (start >= 0) { token = cp_lexer_advance_token (parser->lexer, parser->lexer->first_token, start); cp_lexer_purge_tokens_after (parser->lexer, token); } if (is_identifier) *is_identifier = true; return identifier; } /* If the "template" keyword is present, then there is generally no point in doing name-lookup, so we just return IDENTIFIER. But, if the qualifying scope is non-dependent then we can (and must) do name-lookup normally. */ if (template_keyword_p && (!parser->scope || (TYPE_P (parser->scope) && dependent_type_p (parser->scope)))) return identifier; } /* Look up the name. */ decl = cp_parser_lookup_name (parser, identifier, /*is_type=*/false, /*is_template=*/false, /*is_namespace=*/false, check_dependency_p); decl = maybe_get_template_decl_from_type_decl (decl); /* If DECL is a template, then the name was a template-name. */ if (TREE_CODE (decl) == TEMPLATE_DECL) ; else { /* The standard does not explicitly indicate whether a name that names a set of overloaded declarations, some of which are templates, is a template-name. However, such a name should be a template-name; otherwise, there is no way to form a template-id for the overloaded templates. */ fns = BASELINK_P (decl) ? BASELINK_FUNCTIONS (decl) : decl; if (TREE_CODE (fns) == OVERLOAD) { tree fn; for (fn = fns; fn; fn = OVL_NEXT (fn)) if (TREE_CODE (OVL_CURRENT (fn)) == TEMPLATE_DECL) break; } else { /* Otherwise, the name does not name a template. */ cp_parser_error (parser, "expected template-name"); return error_mark_node; } } /* If DECL is dependent, and refers to a function, then just return its name; we will look it up again during template instantiation. */ if (DECL_FUNCTION_TEMPLATE_P (decl) || !DECL_P (decl)) { tree scope = CP_DECL_CONTEXT (get_first_fn (decl)); if (TYPE_P (scope) && dependent_type_p (scope)) return identifier; } return decl; } /* Parse a template-argument-list. template-argument-list: template-argument template-argument-list , template-argument Returns a TREE_VEC containing the arguments. */ static tree cp_parser_template_argument_list (cp_parser* parser) { tree fixed_args[10]; unsigned n_args = 0; unsigned alloced = 10; tree *arg_ary = fixed_args; tree vec; bool saved_in_template_argument_list_p; saved_in_template_argument_list_p = parser->in_template_argument_list_p; parser->in_template_argument_list_p = true; do { tree argument; if (n_args) /* Consume the comma. */ cp_lexer_consume_token (parser->lexer); /* Parse the template-argument. */ argument = cp_parser_template_argument (parser); if (n_args == alloced) { alloced *= 2; if (arg_ary == fixed_args) { arg_ary = xmalloc (sizeof (tree) * alloced); memcpy (arg_ary, fixed_args, sizeof (tree) * n_args); } else arg_ary = xrealloc (arg_ary, sizeof (tree) * alloced); } arg_ary[n_args++] = argument; } while (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)); vec = make_tree_vec (n_args); while (n_args--) TREE_VEC_ELT (vec, n_args) = arg_ary[n_args]; if (arg_ary != fixed_args) free (arg_ary); parser->in_template_argument_list_p = saved_in_template_argument_list_p; return vec; } /* Parse a template-argument. template-argument: assignment-expression type-id id-expression The representation is that of an assignment-expression, type-id, or id-expression -- except that the qualified id-expression is evaluated, so that the value returned is either a DECL or an OVERLOAD. Although the standard says "assignment-expression", it forbids throw-expressions or assignments in the template argument. Therefore, we use "conditional-expression" instead. */ static tree cp_parser_template_argument (cp_parser* parser) { tree argument; bool template_p; bool address_p; bool maybe_type_id = false; cp_token *token; cp_id_kind idk; tree qualifying_class; /* There's really no way to know what we're looking at, so we just try each alternative in order. [temp.arg] In a template-argument, an ambiguity between a type-id and an expression is resolved to a type-id, regardless of the form of the corresponding template-parameter. Therefore, we try a type-id first. */ cp_parser_parse_tentatively (parser); argument = cp_parser_type_id (parser); /* If there was no error parsing the type-id but the next token is a '>>', we probably found a typo for '> >'. But there are type-id which are also valid expressions. For instance: struct X { int operator >> (int); }; template struct Foo {}; Foo> 5> r; Here 'X()' is a valid type-id of a function type, but the user just wanted to write the expression "X() >> 5". Thus, we remember that we found a valid type-id, but we still try to parse the argument as an expression to see what happens. */ if (!cp_parser_error_occurred (parser) && cp_lexer_next_token_is (parser->lexer, CPP_RSHIFT)) { maybe_type_id = true; cp_parser_abort_tentative_parse (parser); } else { /* If the next token isn't a `,' or a `>', then this argument wasn't really finished. This means that the argument is not a valid type-id. */ if (!cp_parser_next_token_ends_template_argument_p (parser)) cp_parser_error (parser, "expected template-argument"); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) return argument; } /* We're still not sure what the argument will be. */ cp_parser_parse_tentatively (parser); /* Try a template. */ argument = cp_parser_id_expression (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, &template_p, /*declarator_p=*/false); /* If the next token isn't a `,' or a `>', then this argument wasn't really finished. */ if (!cp_parser_next_token_ends_template_argument_p (parser)) cp_parser_error (parser, "expected template-argument"); if (!cp_parser_error_occurred (parser)) { /* Figure out what is being referred to. If the id-expression was for a class template specialization, then we will have a TYPE_DECL at this point. There is no need to do name lookup at this point in that case. */ if (TREE_CODE (argument) != TYPE_DECL) argument = cp_parser_lookup_name (parser, argument, /*is_type=*/false, /*is_template=*/template_p, /*is_namespace=*/false, /*check_dependency=*/true); if (TREE_CODE (argument) != TEMPLATE_DECL && TREE_CODE (argument) != UNBOUND_CLASS_TEMPLATE) cp_parser_error (parser, "expected template-name"); } if (cp_parser_parse_definitely (parser)) return argument; /* It must be a non-type argument. There permitted cases are given in [temp.arg.nontype]: -- an integral constant-expression of integral or enumeration type; or -- the name of a non-type template-parameter; or -- the name of an object or function with external linkage... -- the address of an object or function with external linkage... -- a pointer to member... */ /* Look for a non-type template parameter. */ if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)) { cp_parser_parse_tentatively (parser); argument = cp_parser_primary_expression (parser, &idk, &qualifying_class); if (TREE_CODE (argument) != TEMPLATE_PARM_INDEX || !cp_parser_next_token_ends_template_argument_p (parser)) cp_parser_simulate_error (parser); if (cp_parser_parse_definitely (parser)) return argument; } /* If the next token is "&", the argument must be the address of an object or function with external linkage. */ address_p = cp_lexer_next_token_is (parser->lexer, CPP_AND); if (address_p) cp_lexer_consume_token (parser->lexer); /* See if we might have an id-expression. */ token = cp_lexer_peek_token (parser->lexer); if (token->type == CPP_NAME || token->keyword == RID_OPERATOR || token->type == CPP_SCOPE || token->type == CPP_TEMPLATE_ID || token->type == CPP_NESTED_NAME_SPECIFIER) { cp_parser_parse_tentatively (parser); argument = cp_parser_primary_expression (parser, &idk, &qualifying_class); if (cp_parser_error_occurred (parser) || !cp_parser_next_token_ends_template_argument_p (parser)) cp_parser_abort_tentative_parse (parser); else { if (qualifying_class) argument = finish_qualified_id_expr (qualifying_class, argument, /*done=*/true, address_p); if (TREE_CODE (argument) == VAR_DECL) { /* A variable without external linkage might still be a valid constant-expression, so no error is issued here if the external-linkage check fails. */ if (!DECL_EXTERNAL_LINKAGE_P (argument)) cp_parser_simulate_error (parser); } else if (is_overloaded_fn (argument)) /* All overloaded functions are allowed; if the external linkage test does not pass, an error will be issued later. */ ; else if (address_p && (TREE_CODE (argument) == OFFSET_REF || TREE_CODE (argument) == SCOPE_REF)) /* A pointer-to-member. */ ; else cp_parser_simulate_error (parser); if (cp_parser_parse_definitely (parser)) { if (address_p) argument = build_x_unary_op (ADDR_EXPR, argument); return argument; } } } /* If the argument started with "&", there are no other valid alternatives at this point. */ if (address_p) { cp_parser_error (parser, "invalid non-type template argument"); return error_mark_node; } /* If the argument wasn't successfully parsed as a type-id followed by '>>', the argument can only be a constant expression now. Otherwise, we try parsing the constant-expression tentatively, because the argument could really be a type-id. */ if (maybe_type_id) cp_parser_parse_tentatively (parser); argument = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/false, /*non_constant_p=*/NULL); argument = fold_non_dependent_expr (argument); if (!maybe_type_id) return argument; if (!cp_parser_next_token_ends_template_argument_p (parser)) cp_parser_error (parser, "expected template-argument"); if (cp_parser_parse_definitely (parser)) return argument; /* We did our best to parse the argument as a non type-id, but that was the only alternative that matched (albeit with a '>' after it). We can assume it's just a typo from the user, and a diagnostic will then be issued. */ return cp_parser_type_id (parser); } /* Parse an explicit-instantiation. explicit-instantiation: template declaration Although the standard says `declaration', what it really means is: explicit-instantiation: template decl-specifier-seq [opt] declarator [opt] ; Things like `template int S::i = 5, int S::j;' are not supposed to be allowed. A defect report has been filed about this issue. GNU Extension: explicit-instantiation: storage-class-specifier template decl-specifier-seq [opt] declarator [opt] ; function-specifier template decl-specifier-seq [opt] declarator [opt] ; */ static void cp_parser_explicit_instantiation (cp_parser* parser) { int declares_class_or_enum; tree decl_specifiers; tree attributes; tree extension_specifier = NULL_TREE; /* Look for an (optional) storage-class-specifier or function-specifier. */ if (cp_parser_allow_gnu_extensions_p (parser)) { extension_specifier = cp_parser_storage_class_specifier_opt (parser); if (!extension_specifier) extension_specifier = cp_parser_function_specifier_opt (parser); } /* Look for the `template' keyword. */ cp_parser_require_keyword (parser, RID_TEMPLATE, "`template'"); /* Let the front end know that we are processing an explicit instantiation. */ begin_explicit_instantiation (); /* [temp.explicit] says that we are supposed to ignore access control while processing explicit instantiation directives. */ push_deferring_access_checks (dk_no_check); /* Parse a decl-specifier-seq. */ decl_specifiers = cp_parser_decl_specifier_seq (parser, CP_PARSER_FLAGS_OPTIONAL, &attributes, &declares_class_or_enum); /* If there was exactly one decl-specifier, and it declared a class, and there's no declarator, then we have an explicit type instantiation. */ if (declares_class_or_enum && cp_parser_declares_only_class_p (parser)) { tree type; type = check_tag_decl (decl_specifiers); /* Turn access control back on for names used during template instantiation. */ pop_deferring_access_checks (); if (type) do_type_instantiation (type, extension_specifier, /*complain=*/1); } else { tree declarator; tree decl; /* Parse the declarator. */ declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_NAMED, /*ctor_dtor_or_conv_p=*/NULL, /*parenthesized_p=*/NULL); cp_parser_check_for_definition_in_return_type (declarator, declares_class_or_enum); if (declarator != error_mark_node) { decl = grokdeclarator (declarator, decl_specifiers, NORMAL, 0, NULL); /* Turn access control back on for names used during template instantiation. */ pop_deferring_access_checks (); /* Do the explicit instantiation. */ do_decl_instantiation (decl, extension_specifier); } else { pop_deferring_access_checks (); /* Skip the body of the explicit instantiation. */ cp_parser_skip_to_end_of_statement (parser); } } /* We're done with the instantiation. */ end_explicit_instantiation (); cp_parser_consume_semicolon_at_end_of_statement (parser); } /* Parse an explicit-specialization. explicit-specialization: template < > declaration Although the standard says `declaration', what it really means is: explicit-specialization: template <> decl-specifier [opt] init-declarator [opt] ; template <> function-definition template <> explicit-specialization template <> template-declaration */ static void cp_parser_explicit_specialization (cp_parser* parser) { /* Look for the `template' keyword. */ cp_parser_require_keyword (parser, RID_TEMPLATE, "`template'"); /* Look for the `<'. */ cp_parser_require (parser, CPP_LESS, "`<'"); /* Look for the `>'. */ cp_parser_require (parser, CPP_GREATER, "`>'"); /* We have processed another parameter list. */ ++parser->num_template_parameter_lists; /* Let the front end know that we are beginning a specialization. */ begin_specialization (); /* If the next keyword is `template', we need to figure out whether or not we're looking a template-declaration. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_TEMPLATE)) { if (cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_LESS && cp_lexer_peek_nth_token (parser->lexer, 3)->type != CPP_GREATER) cp_parser_template_declaration_after_export (parser, /*member_p=*/false); else cp_parser_explicit_specialization (parser); } else /* Parse the dependent declaration. */ cp_parser_single_declaration (parser, /*member_p=*/false, /*friend_p=*/NULL); /* We're done with the specialization. */ end_specialization (); /* We're done with this parameter list. */ --parser->num_template_parameter_lists; } /* Parse a type-specifier. type-specifier: simple-type-specifier class-specifier enum-specifier elaborated-type-specifier cv-qualifier GNU Extension: type-specifier: __complex__ Returns a representation of the type-specifier. If the type-specifier is a keyword (like `int' or `const', or `__complex__') then the corresponding IDENTIFIER_NODE is returned. For a class-specifier, enum-specifier, or elaborated-type-specifier a TREE_TYPE is returned; otherwise, a TYPE_DECL is returned. If IS_FRIEND is TRUE then this type-specifier is being declared a `friend'. If IS_DECLARATION is TRUE, then this type-specifier is appearing in a decl-specifier-seq. If DECLARES_CLASS_OR_ENUM is non-NULL, and the type-specifier is a class-specifier, enum-specifier, or elaborated-type-specifier, then *DECLARES_CLASS_OR_ENUM is set to a nonzero value. The value is 1 if a type is declared; 2 if it is defined. Otherwise, it is set to zero. If IS_CV_QUALIFIER is non-NULL, and the type-specifier is a cv-qualifier, then IS_CV_QUALIFIER is set to TRUE. Otherwise, it is set to FALSE. */ static tree cp_parser_type_specifier (cp_parser* parser, cp_parser_flags flags, bool is_friend, bool is_declaration, int* declares_class_or_enum, bool* is_cv_qualifier) { tree type_spec = NULL_TREE; cp_token *token; enum rid keyword; /* Assume this type-specifier does not declare a new type. */ if (declares_class_or_enum) *declares_class_or_enum = 0; /* And that it does not specify a cv-qualifier. */ if (is_cv_qualifier) *is_cv_qualifier = false; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If we're looking at a keyword, we can use that to guide the production we choose. */ keyword = token->keyword; switch (keyword) { /* Any of these indicate either a class-specifier, or an elaborated-type-specifier. */ case RID_CLASS: case RID_STRUCT: case RID_UNION: case RID_ENUM: /* Parse tentatively so that we can back up if we don't find a class-specifier or enum-specifier. */ cp_parser_parse_tentatively (parser); /* Look for the class-specifier or enum-specifier. */ if (keyword == RID_ENUM) type_spec = cp_parser_enum_specifier (parser); else type_spec = cp_parser_class_specifier (parser); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) { if (declares_class_or_enum) *declares_class_or_enum = 2; return type_spec; } /* Fall through. */ case RID_TYPENAME: /* Look for an elaborated-type-specifier. */ type_spec = cp_parser_elaborated_type_specifier (parser, is_friend, is_declaration); /* We're declaring a class or enum -- unless we're using `typename'. */ if (declares_class_or_enum && keyword != RID_TYPENAME) *declares_class_or_enum = 1; return type_spec; case RID_CONST: case RID_VOLATILE: case RID_RESTRICT: type_spec = cp_parser_cv_qualifier_opt (parser); /* Even though we call a routine that looks for an optional qualifier, we know that there should be one. */ my_friendly_assert (type_spec != NULL, 20000328); /* This type-specifier was a cv-qualified. */ if (is_cv_qualifier) *is_cv_qualifier = true; return type_spec; case RID_COMPLEX: /* The `__complex__' keyword is a GNU extension. */ return cp_lexer_consume_token (parser->lexer)->value; default: break; } /* If we do not already have a type-specifier, assume we are looking at a simple-type-specifier. */ type_spec = cp_parser_simple_type_specifier (parser, flags, /*identifier_p=*/true); /* If we didn't find a type-specifier, and a type-specifier was not optional in this context, issue an error message. */ if (!type_spec && !(flags & CP_PARSER_FLAGS_OPTIONAL)) { cp_parser_error (parser, "expected type specifier"); return error_mark_node; } return type_spec; } /* Parse a simple-type-specifier. simple-type-specifier: :: [opt] nested-name-specifier [opt] type-name :: [opt] nested-name-specifier template template-id char wchar_t bool short int long signed unsigned float double void GNU Extension: simple-type-specifier: __typeof__ unary-expression __typeof__ ( type-id ) For the various keywords, the value returned is simply the TREE_IDENTIFIER representing the keyword if IDENTIFIER_P is true. For the first two productions, and if IDENTIFIER_P is false, the value returned is the indicated TYPE_DECL. */ static tree cp_parser_simple_type_specifier (cp_parser* parser, cp_parser_flags flags, bool identifier_p) { tree type = NULL_TREE; cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If we're looking at a keyword, things are easy. */ switch (token->keyword) { case RID_CHAR: type = char_type_node; break; case RID_WCHAR: type = wchar_type_node; break; case RID_BOOL: type = boolean_type_node; break; case RID_SHORT: type = short_integer_type_node; break; case RID_INT: type = integer_type_node; break; case RID_LONG: type = long_integer_type_node; break; case RID_SIGNED: type = integer_type_node; break; case RID_UNSIGNED: type = unsigned_type_node; break; case RID_FLOAT: type = float_type_node; break; case RID_DOUBLE: type = double_type_node; break; case RID_VOID: type = void_type_node; break; case RID_TYPEOF: { tree operand; /* Consume the `typeof' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the operand to `typeof'. */ operand = cp_parser_sizeof_operand (parser, RID_TYPEOF); /* If it is not already a TYPE, take its type. */ if (!TYPE_P (operand)) operand = finish_typeof (operand); return operand; } default: break; } /* If the type-specifier was for a built-in type, we're done. */ if (type) { tree id; /* Consume the token. */ id = cp_lexer_consume_token (parser->lexer)->value; /* There is no valid C++ program where a non-template type is followed by a "<". That usually indicates that the user thought that the type was a template. */ cp_parser_check_for_invalid_template_id (parser, type); return identifier_p ? id : TYPE_NAME (type); } /* The type-specifier must be a user-defined type. */ if (!(flags & CP_PARSER_FLAGS_NO_USER_DEFINED_TYPES)) { bool qualified_p; /* Don't gobble tokens or issue error messages if this is an optional type-specifier. */ if (flags & CP_PARSER_FLAGS_OPTIONAL) cp_parser_parse_tentatively (parser); /* Look for the optional `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* Look for the nested-name specifier. */ qualified_p = (cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/false) != NULL_TREE); /* If we have seen a nested-name-specifier, and the next token is `template', then we are using the template-id production. */ if (parser->scope && cp_parser_optional_template_keyword (parser)) { /* Look for the template-id. */ type = cp_parser_template_id (parser, /*template_keyword_p=*/true, /*check_dependency_p=*/true, /*is_declaration=*/false); /* If the template-id did not name a type, we are out of luck. */ if (TREE_CODE (type) != TYPE_DECL) { cp_parser_error (parser, "expected template-id for type"); type = NULL_TREE; } } /* Otherwise, look for a type-name. */ else type = cp_parser_type_name (parser); /* Keep track of all name-lookups performed in class scopes. */ if (type && !qualified_p && TREE_CODE (type) == TYPE_DECL && TREE_CODE (DECL_NAME (type)) == IDENTIFIER_NODE) maybe_note_name_used_in_class (DECL_NAME (type), type); /* If it didn't work out, we don't have a TYPE. */ if ((flags & CP_PARSER_FLAGS_OPTIONAL) && !cp_parser_parse_definitely (parser)) type = NULL_TREE; } /* If we didn't get a type-name, issue an error message. */ if (!type && !(flags & CP_PARSER_FLAGS_OPTIONAL)) { cp_parser_error (parser, "expected type-name"); return error_mark_node; } /* There is no valid C++ program where a non-template type is followed by a "<". That usually indicates that the user thought that the type was a template. */ if (type && type != error_mark_node) cp_parser_check_for_invalid_template_id (parser, TREE_TYPE (type)); return type; } /* Parse a type-name. type-name: class-name enum-name typedef-name enum-name: identifier typedef-name: identifier Returns a TYPE_DECL for the the type. */ static tree cp_parser_type_name (cp_parser* parser) { tree type_decl; tree identifier; /* We can't know yet whether it is a class-name or not. */ cp_parser_parse_tentatively (parser); /* Try a class-name. */ type_decl = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, /*type_p=*/false, /*check_dependency_p=*/true, /*class_head_p=*/false, /*is_declaration=*/false); /* If it's not a class-name, keep looking. */ if (!cp_parser_parse_definitely (parser)) { /* It must be a typedef-name or an enum-name. */ identifier = cp_parser_identifier (parser); if (identifier == error_mark_node) return error_mark_node; /* Look up the type-name. */ type_decl = cp_parser_lookup_name_simple (parser, identifier); /* Issue an error if we did not find a type-name. */ if (TREE_CODE (type_decl) != TYPE_DECL) { if (!cp_parser_simulate_error (parser)) cp_parser_name_lookup_error (parser, identifier, type_decl, "is not a type"); type_decl = error_mark_node; } /* Remember that the name was used in the definition of the current class so that we can check later to see if the meaning would have been different after the class was entirely defined. */ else if (type_decl != error_mark_node && !parser->scope) maybe_note_name_used_in_class (identifier, type_decl); } return type_decl; } /* Parse an elaborated-type-specifier. Note that the grammar given here incorporates the resolution to DR68. elaborated-type-specifier: class-key :: [opt] nested-name-specifier [opt] identifier class-key :: [opt] nested-name-specifier [opt] template [opt] template-id enum :: [opt] nested-name-specifier [opt] identifier typename :: [opt] nested-name-specifier identifier typename :: [opt] nested-name-specifier template [opt] template-id GNU extension: elaborated-type-specifier: class-key attributes :: [opt] nested-name-specifier [opt] identifier class-key attributes :: [opt] nested-name-specifier [opt] template [opt] template-id enum attributes :: [opt] nested-name-specifier [opt] identifier If IS_FRIEND is TRUE, then this elaborated-type-specifier is being declared `friend'. If IS_DECLARATION is TRUE, then this elaborated-type-specifier appears in a decl-specifiers-seq, i.e., something is being declared. Returns the TYPE specified. */ static tree cp_parser_elaborated_type_specifier (cp_parser* parser, bool is_friend, bool is_declaration) { enum tag_types tag_type; tree identifier; tree type = NULL_TREE; tree attributes = NULL_TREE; /* See if we're looking at the `enum' keyword. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_ENUM)) { /* Consume the `enum' token. */ cp_lexer_consume_token (parser->lexer); /* Remember that it's an enumeration type. */ tag_type = enum_type; /* Parse the attributes. */ attributes = cp_parser_attributes_opt (parser); } /* Or, it might be `typename'. */ else if (cp_lexer_next_token_is_keyword (parser->lexer, RID_TYPENAME)) { /* Consume the `typename' token. */ cp_lexer_consume_token (parser->lexer); /* Remember that it's a `typename' type. */ tag_type = typename_type; /* The `typename' keyword is only allowed in templates. */ if (!processing_template_decl) pedwarn ("using `typename' outside of template"); } /* Otherwise it must be a class-key. */ else { tag_type = cp_parser_class_key (parser); if (tag_type == none_type) return error_mark_node; /* Parse the attributes. */ attributes = cp_parser_attributes_opt (parser); } /* Look for the `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* Look for the nested-name-specifier. */ if (tag_type == typename_type) { if (cp_parser_nested_name_specifier (parser, /*typename_keyword_p=*/true, /*check_dependency_p=*/true, /*type_p=*/true, is_declaration) == error_mark_node) return error_mark_node; } else /* Even though `typename' is not present, the proposed resolution to Core Issue 180 says that in `class A::B', `B' should be considered a type-name, even if `A' is dependent. */ cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/true, /*check_dependency_p=*/true, /*type_p=*/true, is_declaration); /* For everything but enumeration types, consider a template-id. */ if (tag_type != enum_type) { bool template_p = false; tree decl; /* Allow the `template' keyword. */ template_p = cp_parser_optional_template_keyword (parser); /* If we didn't see `template', we don't know if there's a template-id or not. */ if (!template_p) cp_parser_parse_tentatively (parser); /* Parse the template-id. */ decl = cp_parser_template_id (parser, template_p, /*check_dependency_p=*/true, is_declaration); /* If we didn't find a template-id, look for an ordinary identifier. */ if (!template_p && !cp_parser_parse_definitely (parser)) ; /* If DECL is a TEMPLATE_ID_EXPR, and the `typename' keyword is in effect, then we must assume that, upon instantiation, the template will correspond to a class. */ else if (TREE_CODE (decl) == TEMPLATE_ID_EXPR && tag_type == typename_type) type = make_typename_type (parser->scope, decl, /*complain=*/1); else type = TREE_TYPE (decl); } /* For an enumeration type, consider only a plain identifier. */ if (!type) { identifier = cp_parser_identifier (parser); if (identifier == error_mark_node) { parser->scope = NULL_TREE; return error_mark_node; } /* For a `typename', we needn't call xref_tag. */ if (tag_type == typename_type) return make_typename_type (parser->scope, identifier, /*complain=*/1); /* Look up a qualified name in the usual way. */ if (parser->scope) { tree decl; /* In an elaborated-type-specifier, names are assumed to name types, so we set IS_TYPE to TRUE when calling cp_parser_lookup_name. */ decl = cp_parser_lookup_name (parser, identifier, /*is_type=*/true, /*is_template=*/false, /*is_namespace=*/false, /*check_dependency=*/true); /* If we are parsing friend declaration, DECL may be a TEMPLATE_DECL tree node here. However, we need to check whether this TEMPLATE_DECL results in valid code. Consider the following example: namespace N { template class C {}; } class X { template friend class N::C; // #1, valid code }; template class Y { friend class N::C; // #2, invalid code }; For both case #1 and #2, we arrive at a TEMPLATE_DECL after name lookup of `N::C'. We see that friend declaration must be template for the code to be valid. Note that processing_template_decl does not work here since it is always 1 for the above two cases. */ decl = (cp_parser_maybe_treat_template_as_class (decl, /*tag_name_p=*/is_friend && parser->num_template_parameter_lists)); if (TREE_CODE (decl) != TYPE_DECL) { error ("expected type-name"); return error_mark_node; } if (TREE_CODE (TREE_TYPE (decl)) != TYPENAME_TYPE) check_elaborated_type_specifier (tag_type, decl, (parser->num_template_parameter_lists || DECL_SELF_REFERENCE_P (decl))); type = TREE_TYPE (decl); } else { /* An elaborated-type-specifier sometimes introduces a new type and sometimes names an existing type. Normally, the rule is that it introduces a new type only if there is not an existing type of the same name already in scope. For example, given: struct S {}; void f() { struct S s; } the `struct S' in the body of `f' is the same `struct S' as in the global scope; the existing definition is used. However, if there were no global declaration, this would introduce a new local class named `S'. An exception to this rule applies to the following code: namespace N { struct S; } Here, the elaborated-type-specifier names a new type unconditionally; even if there is already an `S' in the containing scope this declaration names a new type. This exception only applies if the elaborated-type-specifier forms the complete declaration: [class.name] A declaration consisting solely of `class-key identifier ;' is either a redeclaration of the name in the current scope or a forward declaration of the identifier as a class name. It introduces the name into the current scope. We are in this situation precisely when the next token is a `;'. An exception to the exception is that a `friend' declaration does *not* name a new type; i.e., given: struct S { friend struct T; }; `T' is not a new type in the scope of `S'. Also, `new struct S' or `sizeof (struct S)' never results in the definition of a new type; a new type can only be declared in a declaration context. */ /* Warn about attributes. They are ignored. */ if (attributes) warning ("type attributes are honored only at type definition"); type = xref_tag (tag_type, identifier, (is_friend || !is_declaration || cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)), parser->num_template_parameter_lists); } } if (tag_type != enum_type) cp_parser_check_class_key (tag_type, type); /* A "<" cannot follow an elaborated type specifier. If that happens, the user was probably trying to form a template-id. */ cp_parser_check_for_invalid_template_id (parser, type); return type; } /* Parse an enum-specifier. enum-specifier: enum identifier [opt] { enumerator-list [opt] } Returns an ENUM_TYPE representing the enumeration. */ static tree cp_parser_enum_specifier (cp_parser* parser) { cp_token *token; tree identifier = NULL_TREE; tree type; /* Look for the `enum' keyword. */ if (!cp_parser_require_keyword (parser, RID_ENUM, "`enum'")) return error_mark_node; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* See if it is an identifier. */ if (token->type == CPP_NAME) identifier = cp_parser_identifier (parser); /* Look for the `{'. */ if (!cp_parser_require (parser, CPP_OPEN_BRACE, "`{'")) return error_mark_node; /* At this point, we're going ahead with the enum-specifier, even if some other problem occurs. */ cp_parser_commit_to_tentative_parse (parser); /* Issue an error message if type-definitions are forbidden here. */ cp_parser_check_type_definition (parser); /* Create the new type. */ type = start_enum (identifier ? identifier : make_anon_name ()); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's not a `}', then there are some enumerators. */ if (token->type != CPP_CLOSE_BRACE) cp_parser_enumerator_list (parser, type); /* Look for the `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); /* Finish up the enumeration. */ finish_enum (type); return type; } /* Parse an enumerator-list. The enumerators all have the indicated TYPE. enumerator-list: enumerator-definition enumerator-list , enumerator-definition */ static void cp_parser_enumerator_list (cp_parser* parser, tree type) { while (true) { cp_token *token; /* Parse an enumerator-definition. */ cp_parser_enumerator_definition (parser, type); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's not a `,', then we've reached the end of the list. */ if (token->type != CPP_COMMA) break; /* Otherwise, consume the `,' and keep going. */ cp_lexer_consume_token (parser->lexer); /* If the next token is a `}', there is a trailing comma. */ if (cp_lexer_next_token_is (parser->lexer, CPP_CLOSE_BRACE)) { if (pedantic && !in_system_header) pedwarn ("comma at end of enumerator list"); break; } } } /* Parse an enumerator-definition. The enumerator has the indicated TYPE. enumerator-definition: enumerator enumerator = constant-expression enumerator: identifier */ static void cp_parser_enumerator_definition (cp_parser* parser, tree type) { cp_token *token; tree identifier; tree value; /* Look for the identifier. */ identifier = cp_parser_identifier (parser); if (identifier == error_mark_node) return; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's an `=', then there's an explicit value. */ if (token->type == CPP_EQ) { /* Consume the `=' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the value. */ value = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/false, NULL); } else value = NULL_TREE; /* Create the enumerator. */ build_enumerator (identifier, value, type); } /* Parse a namespace-name. namespace-name: original-namespace-name namespace-alias Returns the NAMESPACE_DECL for the namespace. */ static tree cp_parser_namespace_name (cp_parser* parser) { tree identifier; tree namespace_decl; /* Get the name of the namespace. */ identifier = cp_parser_identifier (parser); if (identifier == error_mark_node) return error_mark_node; /* Look up the identifier in the currently active scope. Look only for namespaces, due to: [basic.lookup.udir] When looking up a namespace-name in a using-directive or alias definition, only namespace names are considered. And: [basic.lookup.qual] During the lookup of a name preceding the :: scope resolution operator, object, function, and enumerator names are ignored. (Note that cp_parser_class_or_namespace_name only calls this function if the token after the name is the scope resolution operator.) */ namespace_decl = cp_parser_lookup_name (parser, identifier, /*is_type=*/false, /*is_template=*/false, /*is_namespace=*/true, /*check_dependency=*/true); /* If it's not a namespace, issue an error. */ if (namespace_decl == error_mark_node || TREE_CODE (namespace_decl) != NAMESPACE_DECL) { cp_parser_error (parser, "expected namespace-name"); namespace_decl = error_mark_node; } return namespace_decl; } /* Parse a namespace-definition. namespace-definition: named-namespace-definition unnamed-namespace-definition named-namespace-definition: original-namespace-definition extension-namespace-definition original-namespace-definition: namespace identifier { namespace-body } extension-namespace-definition: namespace original-namespace-name { namespace-body } unnamed-namespace-definition: namespace { namespace-body } */ static void cp_parser_namespace_definition (cp_parser* parser) { tree identifier; /* Look for the `namespace' keyword. */ cp_parser_require_keyword (parser, RID_NAMESPACE, "`namespace'"); /* Get the name of the namespace. We do not attempt to distinguish between an original-namespace-definition and an extension-namespace-definition at this point. The semantic analysis routines are responsible for that. */ if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)) identifier = cp_parser_identifier (parser); else identifier = NULL_TREE; /* Look for the `{' to start the namespace. */ cp_parser_require (parser, CPP_OPEN_BRACE, "`{'"); /* Start the namespace. */ push_namespace (identifier); /* Parse the body of the namespace. */ cp_parser_namespace_body (parser); /* Finish the namespace. */ pop_namespace (); /* Look for the final `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); } /* Parse a namespace-body. namespace-body: declaration-seq [opt] */ static void cp_parser_namespace_body (cp_parser* parser) { cp_parser_declaration_seq_opt (parser); } /* Parse a namespace-alias-definition. namespace-alias-definition: namespace identifier = qualified-namespace-specifier ; */ static void cp_parser_namespace_alias_definition (cp_parser* parser) { tree identifier; tree namespace_specifier; /* Look for the `namespace' keyword. */ cp_parser_require_keyword (parser, RID_NAMESPACE, "`namespace'"); /* Look for the identifier. */ identifier = cp_parser_identifier (parser); if (identifier == error_mark_node) return; /* Look for the `=' token. */ cp_parser_require (parser, CPP_EQ, "`='"); /* Look for the qualified-namespace-specifier. */ namespace_specifier = cp_parser_qualified_namespace_specifier (parser); /* Look for the `;' token. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); /* Register the alias in the symbol table. */ do_namespace_alias (identifier, namespace_specifier); } /* Parse a qualified-namespace-specifier. qualified-namespace-specifier: :: [opt] nested-name-specifier [opt] namespace-name Returns a NAMESPACE_DECL corresponding to the specified namespace. */ static tree cp_parser_qualified_namespace_specifier (cp_parser* parser) { /* Look for the optional `::'. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* Look for the optional nested-name-specifier. */ cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/true); return cp_parser_namespace_name (parser); } /* Parse a using-declaration. using-declaration: using typename [opt] :: [opt] nested-name-specifier unqualified-id ; using :: unqualified-id ; */ static void cp_parser_using_declaration (cp_parser* parser) { cp_token *token; bool typename_p = false; bool global_scope_p; tree decl; tree identifier; tree scope; tree qscope; /* Look for the `using' keyword. */ cp_parser_require_keyword (parser, RID_USING, "`using'"); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* See if it's `typename'. */ if (token->keyword == RID_TYPENAME) { /* Remember that we've seen it. */ typename_p = true; /* Consume the `typename' token. */ cp_lexer_consume_token (parser->lexer); } /* Look for the optional global scope qualification. */ global_scope_p = (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false) != NULL_TREE); /* If we saw `typename', or didn't see `::', then there must be a nested-name-specifier present. */ if (typename_p || !global_scope_p) qscope = cp_parser_nested_name_specifier (parser, typename_p, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/true); /* Otherwise, we could be in either of the two productions. In that case, treat the nested-name-specifier as optional. */ else qscope = cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/true); if (!qscope) qscope = global_namespace; /* Parse the unqualified-id. */ identifier = cp_parser_unqualified_id (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, /*declarator_p=*/true); /* The function we call to handle a using-declaration is different depending on what scope we are in. */ if (identifier == error_mark_node) ; else if (TREE_CODE (identifier) != IDENTIFIER_NODE && TREE_CODE (identifier) != BIT_NOT_EXPR) /* [namespace.udecl] A using declaration shall not name a template-id. */ error ("a template-id may not appear in a using-declaration"); else { scope = current_scope (); if (scope && TYPE_P (scope)) { /* Create the USING_DECL. */ decl = do_class_using_decl (build_nt (SCOPE_REF, parser->scope, identifier)); /* Add it to the list of members in this class. */ finish_member_declaration (decl); } else { decl = cp_parser_lookup_name_simple (parser, identifier); if (decl == error_mark_node) cp_parser_name_lookup_error (parser, identifier, decl, NULL); else if (scope) do_local_using_decl (decl, qscope, identifier); else do_toplevel_using_decl (decl, qscope, identifier); } } /* Look for the final `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); } /* Parse a using-directive. using-directive: using namespace :: [opt] nested-name-specifier [opt] namespace-name ; */ static void cp_parser_using_directive (cp_parser* parser) { tree namespace_decl; tree attribs; /* Look for the `using' keyword. */ cp_parser_require_keyword (parser, RID_USING, "`using'"); /* And the `namespace' keyword. */ cp_parser_require_keyword (parser, RID_NAMESPACE, "`namespace'"); /* Look for the optional `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* And the optional nested-name-specifier. */ cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/true); /* Get the namespace being used. */ namespace_decl = cp_parser_namespace_name (parser); /* And any specified attributes. */ attribs = cp_parser_attributes_opt (parser); /* Update the symbol table. */ parse_using_directive (namespace_decl, attribs); /* Look for the final `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); } /* Parse an asm-definition. asm-definition: asm ( string-literal ) ; GNU Extension: asm-definition: asm volatile [opt] ( string-literal ) ; asm volatile [opt] ( string-literal : asm-operand-list [opt] ) ; asm volatile [opt] ( string-literal : asm-operand-list [opt] : asm-operand-list [opt] ) ; asm volatile [opt] ( string-literal : asm-operand-list [opt] : asm-operand-list [opt] : asm-operand-list [opt] ) ; */ static void cp_parser_asm_definition (cp_parser* parser) { cp_token *token; tree string; tree outputs = NULL_TREE; tree inputs = NULL_TREE; tree clobbers = NULL_TREE; tree asm_stmt; bool volatile_p = false; bool extended_p = false; /* Look for the `asm' keyword. */ cp_parser_require_keyword (parser, RID_ASM, "`asm'"); /* See if the next token is `volatile'. */ if (cp_parser_allow_gnu_extensions_p (parser) && cp_lexer_next_token_is_keyword (parser->lexer, RID_VOLATILE)) { /* Remember that we saw the `volatile' keyword. */ volatile_p = true; /* Consume the token. */ cp_lexer_consume_token (parser->lexer); } /* Look for the opening `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Look for the string. */ token = cp_parser_require (parser, CPP_STRING, "asm body"); if (!token) return; string = token->value; /* If we're allowing GNU extensions, check for the extended assembly syntax. Unfortunately, the `:' tokens need not be separated by a space in C, and so, for compatibility, we tolerate that here too. Doing that means that we have to treat the `::' operator as two `:' tokens. */ if (cp_parser_allow_gnu_extensions_p (parser) && at_function_scope_p () && (cp_lexer_next_token_is (parser->lexer, CPP_COLON) || cp_lexer_next_token_is (parser->lexer, CPP_SCOPE))) { bool inputs_p = false; bool clobbers_p = false; /* The extended syntax was used. */ extended_p = true; /* Look for outputs. */ if (cp_lexer_next_token_is (parser->lexer, CPP_COLON)) { /* Consume the `:'. */ cp_lexer_consume_token (parser->lexer); /* Parse the output-operands. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COLON) && cp_lexer_next_token_is_not (parser->lexer, CPP_SCOPE) && cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN)) outputs = cp_parser_asm_operand_list (parser); } /* If the next token is `::', there are no outputs, and the next token is the beginning of the inputs. */ else if (cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)) { /* Consume the `::' token. */ cp_lexer_consume_token (parser->lexer); /* The inputs are coming next. */ inputs_p = true; } /* Look for inputs. */ if (inputs_p || cp_lexer_next_token_is (parser->lexer, CPP_COLON)) { if (!inputs_p) /* Consume the `:'. */ cp_lexer_consume_token (parser->lexer); /* Parse the output-operands. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COLON) && cp_lexer_next_token_is_not (parser->lexer, CPP_SCOPE) && cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN)) inputs = cp_parser_asm_operand_list (parser); } else if (cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)) /* The clobbers are coming next. */ clobbers_p = true; /* Look for clobbers. */ if (clobbers_p || cp_lexer_next_token_is (parser->lexer, CPP_COLON)) { if (!clobbers_p) /* Consume the `:'. */ cp_lexer_consume_token (parser->lexer); /* Parse the clobbers. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN)) clobbers = cp_parser_asm_clobber_list (parser); } } /* Look for the closing `)'. */ if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) cp_parser_skip_to_closing_parenthesis (parser, true, false, /*consume_paren=*/true); cp_parser_require (parser, CPP_SEMICOLON, "`;'"); /* Create the ASM_STMT. */ if (at_function_scope_p ()) { asm_stmt = finish_asm_stmt (volatile_p ? ridpointers[(int) RID_VOLATILE] : NULL_TREE, string, outputs, inputs, clobbers); /* If the extended syntax was not used, mark the ASM_STMT. */ if (!extended_p) ASM_INPUT_P (asm_stmt) = 1; } else assemble_asm (string); } /* Declarators [gram.dcl.decl] */ /* Parse an init-declarator. init-declarator: declarator initializer [opt] GNU Extension: init-declarator: declarator asm-specification [opt] attributes [opt] initializer [opt] function-definition: decl-specifier-seq [opt] declarator ctor-initializer [opt] function-body decl-specifier-seq [opt] declarator function-try-block GNU Extension: function-definition: __extension__ function-definition The DECL_SPECIFIERS and PREFIX_ATTRIBUTES apply to this declarator. Returns a representation of the entity declared. If MEMBER_P is TRUE, then this declarator appears in a class scope. The new DECL created by this declarator is returned. If FUNCTION_DEFINITION_ALLOWED_P then we handle the declarator and for a function-definition here as well. If the declarator is a declarator for a function-definition, *FUNCTION_DEFINITION_P will be TRUE upon return. By that point, the function-definition will have been completely parsed. FUNCTION_DEFINITION_P may be NULL if FUNCTION_DEFINITION_ALLOWED_P is FALSE. */ static tree cp_parser_init_declarator (cp_parser* parser, tree decl_specifiers, tree prefix_attributes, bool function_definition_allowed_p, bool member_p, int declares_class_or_enum, bool* function_definition_p) { cp_token *token; tree declarator; tree attributes; tree asm_specification; tree initializer; tree decl = NULL_TREE; tree scope; bool is_initialized; bool is_parenthesized_init; bool is_non_constant_init; int ctor_dtor_or_conv_p; bool friend_p; bool pop_p = false; /* Assume that this is not the declarator for a function definition. */ if (function_definition_p) *function_definition_p = false; /* Defer access checks while parsing the declarator; we cannot know what names are accessible until we know what is being declared. */ resume_deferring_access_checks (); /* Parse the declarator. */ declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_NAMED, &ctor_dtor_or_conv_p, /*parenthesized_p=*/NULL); /* Gather up the deferred checks. */ stop_deferring_access_checks (); /* If the DECLARATOR was erroneous, there's no need to go further. */ if (declarator == error_mark_node) return error_mark_node; cp_parser_check_for_definition_in_return_type (declarator, declares_class_or_enum); /* Figure out what scope the entity declared by the DECLARATOR is located in. `grokdeclarator' sometimes changes the scope, so we compute it now. */ scope = get_scope_of_declarator (declarator); /* If we're allowing GNU extensions, look for an asm-specification and attributes. */ if (cp_parser_allow_gnu_extensions_p (parser)) { /* Look for an asm-specification. */ asm_specification = cp_parser_asm_specification_opt (parser); /* And attributes. */ attributes = cp_parser_attributes_opt (parser); } else { asm_specification = NULL_TREE; attributes = NULL_TREE; } /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Check to see if the token indicates the start of a function-definition. */ if (cp_parser_token_starts_function_definition_p (token)) { if (!function_definition_allowed_p) { /* If a function-definition should not appear here, issue an error message. */ cp_parser_error (parser, "a function-definition is not allowed here"); return error_mark_node; } else { /* Neither attributes nor an asm-specification are allowed on a function-definition. */ if (asm_specification) error ("an asm-specification is not allowed on a function-definition"); if (attributes) error ("attributes are not allowed on a function-definition"); /* This is a function-definition. */ *function_definition_p = true; /* Parse the function definition. */ if (member_p) decl = cp_parser_save_member_function_body (parser, decl_specifiers, declarator, prefix_attributes); else decl = (cp_parser_function_definition_from_specifiers_and_declarator (parser, decl_specifiers, prefix_attributes, declarator)); return decl; } } /* [dcl.dcl] Only in function declarations for constructors, destructors, and type conversions can the decl-specifier-seq be omitted. We explicitly postpone this check past the point where we handle function-definitions because we tolerate function-definitions that are missing their return types in some modes. */ if (!decl_specifiers && ctor_dtor_or_conv_p <= 0) { cp_parser_error (parser, "expected constructor, destructor, or type conversion"); return error_mark_node; } /* An `=' or an `(' indicates an initializer. */ is_initialized = (token->type == CPP_EQ || token->type == CPP_OPEN_PAREN); /* If the init-declarator isn't initialized and isn't followed by a `,' or `;', it's not a valid init-declarator. */ if (!is_initialized && token->type != CPP_COMMA && token->type != CPP_SEMICOLON) { cp_parser_error (parser, "expected init-declarator"); return error_mark_node; } /* Because start_decl has side-effects, we should only call it if we know we're going ahead. By this point, we know that we cannot possibly be looking at any other construct. */ cp_parser_commit_to_tentative_parse (parser); /* If the decl specifiers were bad, issue an error now that we're sure this was intended to be a declarator. Then continue declaring the variable(s), as int, to try to cut down on further errors. */ if (decl_specifiers != NULL && TREE_VALUE (decl_specifiers) == error_mark_node) { cp_parser_error (parser, "invalid type in declaration"); TREE_VALUE (decl_specifiers) = integer_type_node; } /* Check to see whether or not this declaration is a friend. */ friend_p = cp_parser_friend_p (decl_specifiers); /* Check that the number of template-parameter-lists is OK. */ if (!cp_parser_check_declarator_template_parameters (parser, declarator)) return error_mark_node; /* Enter the newly declared entry in the symbol table. If we're processing a declaration in a class-specifier, we wait until after processing the initializer. */ if (!member_p) { if (parser->in_unbraced_linkage_specification_p) { decl_specifiers = tree_cons (error_mark_node, get_identifier ("extern"), decl_specifiers); have_extern_spec = false; } decl = start_decl (declarator, decl_specifiers, is_initialized, attributes, prefix_attributes); } /* Enter the SCOPE. That way unqualified names appearing in the initializer will be looked up in SCOPE. */ if (scope) pop_p = push_scope (scope); /* Perform deferred access control checks, now that we know in which SCOPE the declared entity resides. */ if (!member_p && decl) { tree saved_current_function_decl = NULL_TREE; /* If the entity being declared is a function, pretend that we are in its scope. If it is a `friend', it may have access to things that would not otherwise be accessible. */ if (TREE_CODE (decl) == FUNCTION_DECL) { saved_current_function_decl = current_function_decl; current_function_decl = decl; } /* Perform the access control checks for the declarator and the the decl-specifiers. */ perform_deferred_access_checks (); /* Restore the saved value. */ if (TREE_CODE (decl) == FUNCTION_DECL) current_function_decl = saved_current_function_decl; } /* Parse the initializer. */ if (is_initialized) initializer = cp_parser_initializer (parser, &is_parenthesized_init, &is_non_constant_init); else { initializer = NULL_TREE; is_parenthesized_init = false; is_non_constant_init = true; } /* The old parser allows attributes to appear after a parenthesized initializer. Mark Mitchell proposed removing this functionality on the GCC mailing lists on 2002-08-13. This parser accepts the attributes -- but ignores them. */ if (cp_parser_allow_gnu_extensions_p (parser) && is_parenthesized_init) if (cp_parser_attributes_opt (parser)) warning ("attributes after parenthesized initializer ignored"); /* Leave the SCOPE, now that we have processed the initializer. It is important to do this before calling cp_finish_decl because it makes decisions about whether to create DECL_STMTs or not based on the current scope. */ if (pop_p) pop_scope (scope); /* For an in-class declaration, use `grokfield' to create the declaration. */ if (member_p) { decl = grokfield (declarator, decl_specifiers, initializer, /*asmspec=*/NULL_TREE, /*attributes=*/NULL_TREE); if (decl && TREE_CODE (decl) == FUNCTION_DECL) cp_parser_save_default_args (parser, decl); } /* Finish processing the declaration. But, skip friend declarations. */ if (!friend_p && decl) cp_finish_decl (decl, initializer, asm_specification, /* If the initializer is in parentheses, then this is a direct-initialization, which means that an `explicit' constructor is OK. Otherwise, an `explicit' constructor cannot be used. */ ((is_parenthesized_init || !is_initialized) ? 0 : LOOKUP_ONLYCONVERTING)); /* Remember whether or not variables were initialized by constant-expressions. */ if (decl && TREE_CODE (decl) == VAR_DECL && is_initialized && !is_non_constant_init) DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = true; return decl; } /* Parse a declarator. declarator: direct-declarator ptr-operator declarator abstract-declarator: ptr-operator abstract-declarator [opt] direct-abstract-declarator GNU Extensions: declarator: attributes [opt] direct-declarator attributes [opt] ptr-operator declarator abstract-declarator: attributes [opt] ptr-operator abstract-declarator [opt] attributes [opt] direct-abstract-declarator Returns a representation of the declarator. If the declarator has the form `* declarator', then an INDIRECT_REF is returned, whose only operand is the sub-declarator. Analogously, `& declarator' is represented as an ADDR_EXPR. For `X::* declarator', a SCOPE_REF is used. The first operand is the TYPE for `X'. The second operand is an INDIRECT_REF whose operand is the sub-declarator. Otherwise, the representation is as for a direct-declarator. (It would be better to define a structure type to represent declarators, rather than abusing `tree' nodes to represent declarators. That would be much clearer and save some memory. There is no reason for declarators to be garbage-collected, for example; they are created during parser and no longer needed after `grokdeclarator' has been called.) For a ptr-operator that has the optional cv-qualifier-seq, cv-qualifiers will be stored in the TREE_TYPE of the INDIRECT_REF node. If CTOR_DTOR_OR_CONV_P is not NULL, *CTOR_DTOR_OR_CONV_P is used to detect constructor, destructor or conversion operators. It is set to -1 if the declarator is a name, and +1 if it is a function. Otherwise it is set to zero. Usually you just want to test for >0, but internally the negative value is used. (The reason for CTOR_DTOR_OR_CONV_P is that a declaration must have a decl-specifier-seq unless it declares a constructor, destructor, or conversion. It might seem that we could check this condition in semantic analysis, rather than parsing, but that makes it difficult to handle something like `f()'. We want to notice that there are no decl-specifiers, and therefore realize that this is an expression, not a declaration.) If PARENTHESIZED_P is non-NULL, *PARENTHESIZED_P is set to true iff the declarator is a direct-declarator of the form "(...)". */ static tree cp_parser_declarator (cp_parser* parser, cp_parser_declarator_kind dcl_kind, int* ctor_dtor_or_conv_p, bool* parenthesized_p) { cp_token *token; tree declarator; enum tree_code code; tree cv_qualifier_seq; tree class_type; tree attributes = NULL_TREE; /* Assume this is not a constructor, destructor, or type-conversion operator. */ if (ctor_dtor_or_conv_p) *ctor_dtor_or_conv_p = 0; if (cp_parser_allow_gnu_extensions_p (parser)) attributes = cp_parser_attributes_opt (parser); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Check for the ptr-operator production. */ cp_parser_parse_tentatively (parser); /* Parse the ptr-operator. */ code = cp_parser_ptr_operator (parser, &class_type, &cv_qualifier_seq); /* If that worked, then we have a ptr-operator. */ if (cp_parser_parse_definitely (parser)) { /* If a ptr-operator was found, then this declarator was not parenthesized. */ if (parenthesized_p) *parenthesized_p = true; /* The dependent declarator is optional if we are parsing an abstract-declarator. */ if (dcl_kind != CP_PARSER_DECLARATOR_NAMED) cp_parser_parse_tentatively (parser); /* Parse the dependent declarator. */ declarator = cp_parser_declarator (parser, dcl_kind, /*ctor_dtor_or_conv_p=*/NULL, /*parenthesized_p=*/NULL); /* If we are parsing an abstract-declarator, we must handle the case where the dependent declarator is absent. */ if (dcl_kind != CP_PARSER_DECLARATOR_NAMED && !cp_parser_parse_definitely (parser)) declarator = NULL_TREE; /* Build the representation of the ptr-operator. */ if (code == INDIRECT_REF) declarator = make_pointer_declarator (cv_qualifier_seq, declarator); else declarator = make_reference_declarator (cv_qualifier_seq, declarator); /* Handle the pointer-to-member case. */ if (class_type) declarator = build_nt (SCOPE_REF, class_type, declarator); } /* Everything else is a direct-declarator. */ else { if (parenthesized_p) *parenthesized_p = cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN); declarator = cp_parser_direct_declarator (parser, dcl_kind, ctor_dtor_or_conv_p); } if (attributes && declarator != error_mark_node) declarator = tree_cons (attributes, declarator, NULL_TREE); return declarator; } /* Parse a direct-declarator or direct-abstract-declarator. direct-declarator: declarator-id direct-declarator ( parameter-declaration-clause ) cv-qualifier-seq [opt] exception-specification [opt] direct-declarator [ constant-expression [opt] ] ( declarator ) direct-abstract-declarator: direct-abstract-declarator [opt] ( parameter-declaration-clause ) cv-qualifier-seq [opt] exception-specification [opt] direct-abstract-declarator [opt] [ constant-expression [opt] ] ( abstract-declarator ) Returns a representation of the declarator. DCL_KIND is CP_PARSER_DECLARATOR_ABSTRACT, if we are parsing a direct-abstract-declarator. It is CP_PARSER_DECLARATOR_NAMED, if we are parsing a direct-declarator. It is CP_PARSER_DECLARATOR_EITHER, if we can accept either - in the case of ambiguity we prefer an abstract declarator, as per [dcl.ambig.res]. CTOR_DTOR_OR_CONV_P is as for cp_parser_declarator. For the declarator-id production, the representation is as for an id-expression, except that a qualified name is represented as a SCOPE_REF. A function-declarator is represented as a CALL_EXPR; see the documentation of the FUNCTION_DECLARATOR_* macros for information about how to find the various declarator components. An array-declarator is represented as an ARRAY_REF. The direct-declarator is the first operand; the constant-expression indicating the size of the array is the second operand. */ static tree cp_parser_direct_declarator (cp_parser* parser, cp_parser_declarator_kind dcl_kind, int* ctor_dtor_or_conv_p) { cp_token *token; tree declarator = NULL_TREE; tree scope = NULL_TREE; bool saved_default_arg_ok_p = parser->default_arg_ok_p; bool saved_in_declarator_p = parser->in_declarator_p; bool first = true; bool pop_p = false; while (true) { /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); if (token->type == CPP_OPEN_PAREN) { /* This is either a parameter-declaration-clause, or a parenthesized declarator. When we know we are parsing a named declarator, it must be a parenthesized declarator if FIRST is true. For instance, `(int)' is a parameter-declaration-clause, with an omitted direct-abstract-declarator. But `((*))', is a parenthesized abstract declarator. Finally, when T is a template parameter `(T)' is a parameter-declaration-clause, and not a parenthesized named declarator. We first try and parse a parameter-declaration-clause, and then try a nested declarator (if FIRST is true). It is not an error for it not to be a parameter-declaration-clause, even when FIRST is false. Consider, int i (int); int i (3); The first is the declaration of a function while the second is a the definition of a variable, including its initializer. Having seen only the parenthesis, we cannot know which of these two alternatives should be selected. Even more complex are examples like: int i (int (a)); int i (int (3)); The former is a function-declaration; the latter is a variable initialization. Thus again, we try a parameter-declaration-clause, and if that fails, we back out and return. */ if (!first || dcl_kind != CP_PARSER_DECLARATOR_NAMED) { tree params; unsigned saved_num_template_parameter_lists; cp_parser_parse_tentatively (parser); /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); if (first) { /* If this is going to be an abstract declarator, we're in a declarator and we can't have default args. */ parser->default_arg_ok_p = false; parser->in_declarator_p = true; } /* Inside the function parameter list, surrounding template-parameter-lists do not apply. */ saved_num_template_parameter_lists = parser->num_template_parameter_lists; parser->num_template_parameter_lists = 0; /* Parse the parameter-declaration-clause. */ params = cp_parser_parameter_declaration_clause (parser); parser->num_template_parameter_lists = saved_num_template_parameter_lists; /* If all went well, parse the cv-qualifier-seq and the exception-specification. */ if (cp_parser_parse_definitely (parser)) { tree cv_qualifiers; tree exception_specification; if (ctor_dtor_or_conv_p) *ctor_dtor_or_conv_p = *ctor_dtor_or_conv_p < 0; first = false; /* Consume the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Parse the cv-qualifier-seq. */ cv_qualifiers = cp_parser_cv_qualifier_seq_opt (parser); /* And the exception-specification. */ exception_specification = cp_parser_exception_specification_opt (parser); /* Create the function-declarator. */ declarator = make_call_declarator (declarator, params, cv_qualifiers, exception_specification); /* Any subsequent parameter lists are to do with return type, so are not those of the declared function. */ parser->default_arg_ok_p = false; /* Repeat the main loop. */ continue; } } /* If this is the first, we can try a parenthesized declarator. */ if (first) { bool saved_in_type_id_in_expr_p; parser->default_arg_ok_p = saved_default_arg_ok_p; parser->in_declarator_p = saved_in_declarator_p; /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* Parse the nested declarator. */ saved_in_type_id_in_expr_p = parser->in_type_id_in_expr_p; parser->in_type_id_in_expr_p = true; declarator = cp_parser_declarator (parser, dcl_kind, ctor_dtor_or_conv_p, /*parenthesized_p=*/NULL); parser->in_type_id_in_expr_p = saved_in_type_id_in_expr_p; first = false; /* Expect a `)'. */ if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) declarator = error_mark_node; if (declarator == error_mark_node) break; goto handle_declarator; } /* Otherwise, we must be done. */ else break; } else if ((!first || dcl_kind != CP_PARSER_DECLARATOR_NAMED) && token->type == CPP_OPEN_SQUARE) { /* Parse an array-declarator. */ tree bounds; if (ctor_dtor_or_conv_p) *ctor_dtor_or_conv_p = 0; first = false; parser->default_arg_ok_p = false; parser->in_declarator_p = true; /* Consume the `['. */ cp_lexer_consume_token (parser->lexer); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If the next token is `]', then there is no constant-expression. */ if (token->type != CPP_CLOSE_SQUARE) { bool non_constant_p; bounds = cp_parser_constant_expression (parser, /*allow_non_constant=*/true, &non_constant_p); if (!non_constant_p) bounds = fold_non_dependent_expr (bounds); } else bounds = NULL_TREE; /* Look for the closing `]'. */ if (!cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'")) { declarator = error_mark_node; break; } declarator = build_nt (ARRAY_REF, declarator, bounds); } else if (first && dcl_kind != CP_PARSER_DECLARATOR_ABSTRACT) { /* Parse a declarator-id */ if (dcl_kind == CP_PARSER_DECLARATOR_EITHER) cp_parser_parse_tentatively (parser); declarator = cp_parser_declarator_id (parser); if (dcl_kind == CP_PARSER_DECLARATOR_EITHER) { if (!cp_parser_parse_definitely (parser)) declarator = error_mark_node; else if (TREE_CODE (declarator) != IDENTIFIER_NODE) { cp_parser_error (parser, "expected unqualified-id"); declarator = error_mark_node; } } if (declarator == error_mark_node) break; if (TREE_CODE (declarator) == SCOPE_REF && !current_scope ()) { tree scope = TREE_OPERAND (declarator, 0); /* In the declaration of a member of a template class outside of the class itself, the SCOPE will sometimes be a TYPENAME_TYPE. For example, given: template int S::R::i = 3; the SCOPE will be a TYPENAME_TYPE for `S::R'. In this context, we must resolve S::R to an ordinary type, rather than a typename type. The reason we normally avoid resolving TYPENAME_TYPEs is that a specialization of `S' might render `S::R' not a type. However, if `S' is specialized, then this `i' will not be used, so there is no harm in resolving the types here. */ if (TREE_CODE (scope) == TYPENAME_TYPE) { tree type; /* Resolve the TYPENAME_TYPE. */ type = resolve_typename_type (scope, /*only_current_p=*/false); /* If that failed, the declarator is invalid. */ if (type == error_mark_node) error ("`%T::%D' is not a type", TYPE_CONTEXT (scope), TYPE_IDENTIFIER (scope)); /* Build a new DECLARATOR. */ declarator = build_nt (SCOPE_REF, type, TREE_OPERAND (declarator, 1)); } } /* Check to see whether the declarator-id names a constructor, destructor, or conversion. */ if (declarator && ctor_dtor_or_conv_p && ((TREE_CODE (declarator) == SCOPE_REF && CLASS_TYPE_P (TREE_OPERAND (declarator, 0))) || (TREE_CODE (declarator) != SCOPE_REF && at_class_scope_p ()))) { tree unqualified_name; tree class_type; /* Get the unqualified part of the name. */ if (TREE_CODE (declarator) == SCOPE_REF) { class_type = TREE_OPERAND (declarator, 0); unqualified_name = TREE_OPERAND (declarator, 1); } else { class_type = current_class_type; unqualified_name = declarator; } /* See if it names ctor, dtor or conv. */ if (TREE_CODE (unqualified_name) == BIT_NOT_EXPR || IDENTIFIER_TYPENAME_P (unqualified_name) || constructor_name_p (unqualified_name, class_type) || (TREE_CODE (unqualified_name) == TYPE_DECL && same_type_p (TREE_TYPE (unqualified_name), class_type))) *ctor_dtor_or_conv_p = -1; } handle_declarator:; scope = get_scope_of_declarator (declarator); if (scope) /* Any names that appear after the declarator-id for a member are looked up in the containing scope. */ pop_p = push_scope (scope); parser->in_declarator_p = true; if ((ctor_dtor_or_conv_p && *ctor_dtor_or_conv_p) || (declarator && (TREE_CODE (declarator) == SCOPE_REF || TREE_CODE (declarator) == IDENTIFIER_NODE))) /* Default args are only allowed on function declarations. */ parser->default_arg_ok_p = saved_default_arg_ok_p; else parser->default_arg_ok_p = false; first = false; } /* We're done. */ else break; } /* For an abstract declarator, we might wind up with nothing at this point. That's an error; the declarator is not optional. */ if (!declarator) cp_parser_error (parser, "expected declarator"); /* If we entered a scope, we must exit it now. */ if (pop_p) pop_scope (scope); parser->default_arg_ok_p = saved_default_arg_ok_p; parser->in_declarator_p = saved_in_declarator_p; return declarator; } /* Parse a ptr-operator. ptr-operator: * cv-qualifier-seq [opt] & :: [opt] nested-name-specifier * cv-qualifier-seq [opt] GNU Extension: ptr-operator: & cv-qualifier-seq [opt] Returns INDIRECT_REF if a pointer, or pointer-to-member, was used. Returns ADDR_EXPR if a reference was used. In the case of a pointer-to-member, *TYPE is filled in with the TYPE containing the member. *CV_QUALIFIER_SEQ is filled in with the cv-qualifier-seq, or NULL_TREE, if there are no cv-qualifiers. Returns ERROR_MARK if an error occurred. */ static enum tree_code cp_parser_ptr_operator (cp_parser* parser, tree* type, tree* cv_qualifier_seq) { enum tree_code code = ERROR_MARK; cp_token *token; /* Assume that it's not a pointer-to-member. */ *type = NULL_TREE; /* And that there are no cv-qualifiers. */ *cv_qualifier_seq = NULL_TREE; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's a `*' or `&' we have a pointer or reference. */ if (token->type == CPP_MULT || token->type == CPP_AND) { /* Remember which ptr-operator we were processing. */ code = (token->type == CPP_AND ? ADDR_EXPR : INDIRECT_REF); /* Consume the `*' or `&'. */ cp_lexer_consume_token (parser->lexer); /* A `*' can be followed by a cv-qualifier-seq, and so can a `&', if we are allowing GNU extensions. (The only qualifier that can legally appear after `&' is `restrict', but that is enforced during semantic analysis. */ if (code == INDIRECT_REF || cp_parser_allow_gnu_extensions_p (parser)) *cv_qualifier_seq = cp_parser_cv_qualifier_seq_opt (parser); } else { /* Try the pointer-to-member case. */ cp_parser_parse_tentatively (parser); /* Look for the optional `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* Look for the nested-name specifier. */ cp_parser_nested_name_specifier (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/false); /* If we found it, and the next token is a `*', then we are indeed looking at a pointer-to-member operator. */ if (!cp_parser_error_occurred (parser) && cp_parser_require (parser, CPP_MULT, "`*'")) { /* The type of which the member is a member is given by the current SCOPE. */ *type = parser->scope; /* The next name will not be qualified. */ parser->scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; parser->object_scope = NULL_TREE; /* Indicate that the `*' operator was used. */ code = INDIRECT_REF; /* Look for the optional cv-qualifier-seq. */ *cv_qualifier_seq = cp_parser_cv_qualifier_seq_opt (parser); } /* If that didn't work we don't have a ptr-operator. */ if (!cp_parser_parse_definitely (parser)) cp_parser_error (parser, "expected ptr-operator"); } return code; } /* Parse an (optional) cv-qualifier-seq. cv-qualifier-seq: cv-qualifier cv-qualifier-seq [opt] Returns a TREE_LIST. The TREE_VALUE of each node is the representation of a cv-qualifier. */ static tree cp_parser_cv_qualifier_seq_opt (cp_parser* parser) { tree cv_qualifiers = NULL_TREE; while (true) { tree cv_qualifier; /* Look for the next cv-qualifier. */ cv_qualifier = cp_parser_cv_qualifier_opt (parser); /* If we didn't find one, we're done. */ if (!cv_qualifier) break; /* Add this cv-qualifier to the list. */ cv_qualifiers = tree_cons (NULL_TREE, cv_qualifier, cv_qualifiers); } /* We built up the list in reverse order. */ return nreverse (cv_qualifiers); } /* Parse an (optional) cv-qualifier. cv-qualifier: const volatile GNU Extension: cv-qualifier: __restrict__ */ static tree cp_parser_cv_qualifier_opt (cp_parser* parser) { cp_token *token; tree cv_qualifier = NULL_TREE; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* See if it's a cv-qualifier. */ switch (token->keyword) { case RID_CONST: case RID_VOLATILE: case RID_RESTRICT: /* Save the value of the token. */ cv_qualifier = token->value; /* Consume the token. */ cp_lexer_consume_token (parser->lexer); break; default: break; } return cv_qualifier; } /* Parse a declarator-id. declarator-id: id-expression :: [opt] nested-name-specifier [opt] type-name In the `id-expression' case, the value returned is as for cp_parser_id_expression if the id-expression was an unqualified-id. If the id-expression was a qualified-id, then a SCOPE_REF is returned. The first operand is the scope (either a NAMESPACE_DECL or TREE_TYPE), but the second is still just a representation of an unqualified-id. */ static tree cp_parser_declarator_id (cp_parser* parser) { tree id_expression; /* The expression must be an id-expression. Assume that qualified names are the names of types so that: template int S::R::i = 3; will work; we must treat `S::R' as the name of a type. Similarly, assume that qualified names are templates, where required, so that: template int S::R::i = 3; will work, too. */ id_expression = cp_parser_id_expression (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/false, /*template_p=*/NULL, /*declarator_p=*/true); /* If the name was qualified, create a SCOPE_REF to represent that. */ if (parser->scope) { id_expression = build_nt (SCOPE_REF, parser->scope, id_expression); parser->scope = NULL_TREE; } return id_expression; } /* Parse a type-id. type-id: type-specifier-seq abstract-declarator [opt] Returns the TYPE specified. */ static tree cp_parser_type_id (cp_parser* parser) { tree type_specifier_seq; tree abstract_declarator; /* Parse the type-specifier-seq. */ type_specifier_seq = cp_parser_type_specifier_seq (parser); if (type_specifier_seq == error_mark_node) return error_mark_node; /* There might or might not be an abstract declarator. */ cp_parser_parse_tentatively (parser); /* Look for the declarator. */ abstract_declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_ABSTRACT, NULL, /*parenthesized_p=*/NULL); /* Check to see if there really was a declarator. */ if (!cp_parser_parse_definitely (parser)) abstract_declarator = NULL_TREE; return groktypename (build_tree_list (type_specifier_seq, abstract_declarator)); } /* Parse a type-specifier-seq. type-specifier-seq: type-specifier type-specifier-seq [opt] GNU extension: type-specifier-seq: attributes type-specifier-seq [opt] Returns a TREE_LIST. Either the TREE_VALUE of each node is a type-specifier, or the TREE_PURPOSE is a list of attributes. */ static tree cp_parser_type_specifier_seq (cp_parser* parser) { bool seen_type_specifier = false; tree type_specifier_seq = NULL_TREE; /* Parse the type-specifiers and attributes. */ while (true) { tree type_specifier; /* Check for attributes first. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_ATTRIBUTE)) { type_specifier_seq = tree_cons (cp_parser_attributes_opt (parser), NULL_TREE, type_specifier_seq); continue; } /* After the first type-specifier, others are optional. */ if (seen_type_specifier) cp_parser_parse_tentatively (parser); /* Look for the type-specifier. */ type_specifier = cp_parser_type_specifier (parser, CP_PARSER_FLAGS_NONE, /*is_friend=*/false, /*is_declaration=*/false, NULL, NULL); /* If the first type-specifier could not be found, this is not a type-specifier-seq at all. */ if (!seen_type_specifier && type_specifier == error_mark_node) return error_mark_node; /* If subsequent type-specifiers could not be found, the type-specifier-seq is complete. */ else if (seen_type_specifier && !cp_parser_parse_definitely (parser)) break; /* Add the new type-specifier to the list. */ type_specifier_seq = tree_cons (NULL_TREE, type_specifier, type_specifier_seq); seen_type_specifier = true; } /* We built up the list in reverse order. */ return nreverse (type_specifier_seq); } /* Parse a parameter-declaration-clause. parameter-declaration-clause: parameter-declaration-list [opt] ... [opt] parameter-declaration-list , ... Returns a representation for the parameter declarations. Each node is a TREE_LIST. (See cp_parser_parameter_declaration for the exact representation.) If the parameter-declaration-clause ends with an ellipsis, PARMLIST_ELLIPSIS_P will hold of the first node in the list. A return value of NULL_TREE indicates a parameter-declaration-clause consisting only of an ellipsis. */ static tree cp_parser_parameter_declaration_clause (cp_parser* parser) { tree parameters; cp_token *token; bool ellipsis_p; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Check for trivial parameter-declaration-clauses. */ if (token->type == CPP_ELLIPSIS) { /* Consume the `...' token. */ cp_lexer_consume_token (parser->lexer); return NULL_TREE; } else if (token->type == CPP_CLOSE_PAREN) /* There are no parameters. */ { #ifndef NO_IMPLICIT_EXTERN_C if (in_system_header && current_class_type == NULL && current_lang_name == lang_name_c) return NULL_TREE; else #endif return void_list_node; } /* Check for `(void)', too, which is a special case. */ else if (token->keyword == RID_VOID && (cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_CLOSE_PAREN)) { /* Consume the `void' token. */ cp_lexer_consume_token (parser->lexer); /* There are no parameters. */ return void_list_node; } /* Parse the parameter-declaration-list. */ parameters = cp_parser_parameter_declaration_list (parser); /* If a parse error occurred while parsing the parameter-declaration-list, then the entire parameter-declaration-clause is erroneous. */ if (parameters == error_mark_node) return error_mark_node; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's a `,', the clause should terminate with an ellipsis. */ if (token->type == CPP_COMMA) { /* Consume the `,'. */ cp_lexer_consume_token (parser->lexer); /* Expect an ellipsis. */ ellipsis_p = (cp_parser_require (parser, CPP_ELLIPSIS, "`...'") != NULL); } /* It might also be `...' if the optional trailing `,' was omitted. */ else if (token->type == CPP_ELLIPSIS) { /* Consume the `...' token. */ cp_lexer_consume_token (parser->lexer); /* And remember that we saw it. */ ellipsis_p = true; } else ellipsis_p = false; /* Finish the parameter list. */ return finish_parmlist (parameters, ellipsis_p); } /* Parse a parameter-declaration-list. parameter-declaration-list: parameter-declaration parameter-declaration-list , parameter-declaration Returns a representation of the parameter-declaration-list, as for cp_parser_parameter_declaration_clause. However, the `void_list_node' is never appended to the list. */ static tree cp_parser_parameter_declaration_list (cp_parser* parser) { tree parameters = NULL_TREE; /* Look for more parameters. */ while (true) { tree parameter; bool parenthesized_p; /* Parse the parameter. */ parameter = cp_parser_parameter_declaration (parser, /*template_parm_p=*/false, &parenthesized_p); /* If a parse error occurred parsing the parameter declaration, then the entire parameter-declaration-list is erroneous. */ if (parameter == error_mark_node) { parameters = error_mark_node; break; } /* Add the new parameter to the list. */ TREE_CHAIN (parameter) = parameters; parameters = parameter; /* Peek at the next token. */ if (cp_lexer_next_token_is (parser->lexer, CPP_CLOSE_PAREN) || cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS)) /* The parameter-declaration-list is complete. */ break; else if (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)) { cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_nth_token (parser->lexer, 2); /* If it's an ellipsis, then the list is complete. */ if (token->type == CPP_ELLIPSIS) break; /* Otherwise, there must be more parameters. Consume the `,'. */ cp_lexer_consume_token (parser->lexer); /* When parsing something like: int i(float f, double d) we can tell after seeing the declaration for "f" that we are not looking at an initialization of a variable "i", but rather at the declaration of a function "i". Due to the fact that the parsing of template arguments (as specified to a template-id) requires backtracking we cannot use this technique when inside a template argument list. */ if (!parser->in_template_argument_list_p && !parser->in_type_id_in_expr_p && cp_parser_parsing_tentatively (parser) && !cp_parser_committed_to_tentative_parse (parser) /* However, a parameter-declaration of the form "foat(f)" (which is a valid declaration of a parameter "f") can also be interpreted as an expression (the conversion of "f" to "float"). */ && !parenthesized_p) cp_parser_commit_to_tentative_parse (parser); } else { cp_parser_error (parser, "expected `,' or `...'"); if (!cp_parser_parsing_tentatively (parser) || cp_parser_committed_to_tentative_parse (parser)) cp_parser_skip_to_closing_parenthesis (parser, /*recovering=*/true, /*or_comma=*/false, /*consume_paren=*/false); break; } } /* We built up the list in reverse order; straighten it out now. */ return nreverse (parameters); } /* Parse a parameter declaration. parameter-declaration: decl-specifier-seq declarator decl-specifier-seq declarator = assignment-expression decl-specifier-seq abstract-declarator [opt] decl-specifier-seq abstract-declarator [opt] = assignment-expression If TEMPLATE_PARM_P is TRUE, then this parameter-declaration declares a template parameter. (In that case, a non-nested `>' token encountered during the parsing of the assignment-expression is not interpreted as a greater-than operator.) Returns a TREE_LIST representing the parameter-declaration. The TREE_PURPOSE is the default argument expression, or NULL_TREE if there is no default argument. The TREE_VALUE is a representation of the decl-specifier-seq and declarator. In particular, the TREE_VALUE will be a TREE_LIST whose TREE_PURPOSE represents the decl-specifier-seq and whose TREE_VALUE represents the declarator. If PARENTHESIZED_P is non-NULL, *PARENTHESIZED_P is set to true iff the declarator is of the form "(p)". */ static tree cp_parser_parameter_declaration (cp_parser *parser, bool template_parm_p, bool *parenthesized_p) { int declares_class_or_enum; bool greater_than_is_operator_p; tree decl_specifiers; tree attributes; tree declarator; tree default_argument; tree parameter; cp_token *token; const char *saved_message; /* In a template parameter, `>' is not an operator. [temp.param] When parsing a default template-argument for a non-type template-parameter, the first non-nested `>' is taken as the end of the template parameter-list rather than a greater-than operator. */ greater_than_is_operator_p = !template_parm_p; /* Type definitions may not appear in parameter types. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in parameter types"; /* Parse the declaration-specifiers. */ decl_specifiers = cp_parser_decl_specifier_seq (parser, CP_PARSER_FLAGS_NONE, &attributes, &declares_class_or_enum); /* If an error occurred, there's no reason to attempt to parse the rest of the declaration. */ if (cp_parser_error_occurred (parser)) { parser->type_definition_forbidden_message = saved_message; return error_mark_node; } /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If the next token is a `)', `,', `=', `>', or `...', then there is no declarator. */ if (token->type == CPP_CLOSE_PAREN || token->type == CPP_COMMA || token->type == CPP_EQ || token->type == CPP_ELLIPSIS || token->type == CPP_GREATER) { declarator = NULL_TREE; if (parenthesized_p) *parenthesized_p = false; } /* Otherwise, there should be a declarator. */ else { bool saved_default_arg_ok_p = parser->default_arg_ok_p; parser->default_arg_ok_p = false; /* After seeing a decl-specifier-seq, if the next token is not a "(", there is no possibility that the code is a valid expression. Therefore, if parsing tentatively, we commit at this point. */ if (!parser->in_template_argument_list_p /* In an expression context, having seen: (int((char ... we cannot be sure whether we are looking at a function-type (taking a "char" as a parameter) or a cast of some object of type "char" to "int". */ && !parser->in_type_id_in_expr_p && cp_parser_parsing_tentatively (parser) && !cp_parser_committed_to_tentative_parse (parser) && cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_PAREN)) cp_parser_commit_to_tentative_parse (parser); /* Parse the declarator. */ declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_EITHER, /*ctor_dtor_or_conv_p=*/NULL, parenthesized_p); parser->default_arg_ok_p = saved_default_arg_ok_p; /* After the declarator, allow more attributes. */ attributes = chainon (attributes, cp_parser_attributes_opt (parser)); } /* The restriction on defining new types applies only to the type of the parameter, not to the default argument. */ parser->type_definition_forbidden_message = saved_message; /* If the next token is `=', then process a default argument. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EQ)) { bool saved_greater_than_is_operator_p; /* Consume the `='. */ cp_lexer_consume_token (parser->lexer); /* If we are defining a class, then the tokens that make up the default argument must be saved and processed later. */ if (!template_parm_p && at_class_scope_p () && TYPE_BEING_DEFINED (current_class_type)) { unsigned depth = 0; /* Create a DEFAULT_ARG to represented the unparsed default argument. */ default_argument = make_node (DEFAULT_ARG); DEFARG_TOKENS (default_argument) = cp_token_cache_new (); /* Add tokens until we have processed the entire default argument. */ while (true) { bool done = false; cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* What we do depends on what token we have. */ switch (token->type) { /* In valid code, a default argument must be immediately followed by a `,' `)', or `...'. */ case CPP_COMMA: case CPP_CLOSE_PAREN: case CPP_ELLIPSIS: /* If we run into a non-nested `;', `}', or `]', then the code is invalid -- but the default argument is certainly over. */ case CPP_SEMICOLON: case CPP_CLOSE_BRACE: case CPP_CLOSE_SQUARE: if (depth == 0) done = true; /* Update DEPTH, if necessary. */ else if (token->type == CPP_CLOSE_PAREN || token->type == CPP_CLOSE_BRACE || token->type == CPP_CLOSE_SQUARE) --depth; break; case CPP_OPEN_PAREN: case CPP_OPEN_SQUARE: case CPP_OPEN_BRACE: ++depth; break; case CPP_GREATER: /* If we see a non-nested `>', and `>' is not an operator, then it marks the end of the default argument. */ if (!depth && !greater_than_is_operator_p) done = true; break; /* If we run out of tokens, issue an error message. */ case CPP_EOF: error ("file ends in default argument"); done = true; break; case CPP_NAME: case CPP_SCOPE: /* In these cases, we should look for template-ids. For example, if the default argument is `X()', we need to do name lookup to figure out whether or not `X' is a template; if so, the `,' does not end the default argument. That is not yet done. */ break; default: break; } /* If we've reached the end, stop. */ if (done) break; /* Add the token to the token block. */ token = cp_lexer_consume_token (parser->lexer); cp_token_cache_push_token (DEFARG_TOKENS (default_argument), token); } } /* Outside of a class definition, we can just parse the assignment-expression. */ else { bool saved_local_variables_forbidden_p; /* Make sure that PARSER->GREATER_THAN_IS_OPERATOR_P is set correctly. */ saved_greater_than_is_operator_p = parser->greater_than_is_operator_p; parser->greater_than_is_operator_p = greater_than_is_operator_p; /* Local variable names (and the `this' keyword) may not appear in a default argument. */ saved_local_variables_forbidden_p = parser->local_variables_forbidden_p; parser->local_variables_forbidden_p = true; /* Parse the assignment-expression. */ default_argument = cp_parser_assignment_expression (parser); /* Restore saved state. */ parser->greater_than_is_operator_p = saved_greater_than_is_operator_p; parser->local_variables_forbidden_p = saved_local_variables_forbidden_p; } if (!parser->default_arg_ok_p) { if (!flag_pedantic_errors) warning ("deprecated use of default argument for parameter of non-function"); else { error ("default arguments are only permitted for function parameters"); default_argument = NULL_TREE; } } } else default_argument = NULL_TREE; /* Create the representation of the parameter. */ if (attributes) decl_specifiers = tree_cons (attributes, NULL_TREE, decl_specifiers); parameter = build_tree_list (default_argument, build_tree_list (decl_specifiers, declarator)); return parameter; } /* Parse a function-body. function-body: compound_statement */ static void cp_parser_function_body (cp_parser *parser) { cp_parser_compound_statement (parser, false); } /* Parse a ctor-initializer-opt followed by a function-body. Return true if a ctor-initializer was present. */ static bool cp_parser_ctor_initializer_opt_and_function_body (cp_parser *parser) { tree body; bool ctor_initializer_p; /* Begin the function body. */ body = begin_function_body (); /* Parse the optional ctor-initializer. */ ctor_initializer_p = cp_parser_ctor_initializer_opt (parser); /* Parse the function-body. */ cp_parser_function_body (parser); /* Finish the function body. */ finish_function_body (body); return ctor_initializer_p; } /* Parse an initializer. initializer: = initializer-clause ( expression-list ) Returns a expression representing the initializer. If no initializer is present, NULL_TREE is returned. *IS_PARENTHESIZED_INIT is set to TRUE if the `( expression-list )' production is used, and zero otherwise. *IS_PARENTHESIZED_INIT is set to FALSE if there is no initializer present. If there is an initializer, and it is not a constant-expression, *NON_CONSTANT_P is set to true; otherwise it is set to false. */ static tree cp_parser_initializer (cp_parser* parser, bool* is_parenthesized_init, bool* non_constant_p) { cp_token *token; tree init; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Let our caller know whether or not this initializer was parenthesized. */ *is_parenthesized_init = (token->type == CPP_OPEN_PAREN); /* Assume that the initializer is constant. */ *non_constant_p = false; if (token->type == CPP_EQ) { /* Consume the `='. */ cp_lexer_consume_token (parser->lexer); /* Parse the initializer-clause. */ init = cp_parser_initializer_clause (parser, non_constant_p); } else if (token->type == CPP_OPEN_PAREN) init = cp_parser_parenthesized_expression_list (parser, false, non_constant_p); else { /* Anything else is an error. */ cp_parser_error (parser, "expected initializer"); init = error_mark_node; } return init; } /* Parse an initializer-clause. initializer-clause: assignment-expression { initializer-list , [opt] } { } Returns an expression representing the initializer. If the `assignment-expression' production is used the value returned is simply a representation for the expression. Otherwise, a CONSTRUCTOR is returned. The CONSTRUCTOR_ELTS will be the elements of the initializer-list (or NULL_TREE, if the last production is used). The TREE_TYPE for the CONSTRUCTOR will be NULL_TREE. There is no way to detect whether or not the optional trailing `,' was provided. NON_CONSTANT_P is as for cp_parser_initializer. */ static tree cp_parser_initializer_clause (cp_parser* parser, bool* non_constant_p) { tree initializer; /* If it is not a `{', then we are looking at an assignment-expression. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_BRACE)) { initializer = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/true, non_constant_p); if (!*non_constant_p) initializer = fold_non_dependent_expr (initializer); } else { /* Consume the `{' token. */ cp_lexer_consume_token (parser->lexer); /* Create a CONSTRUCTOR to represent the braced-initializer. */ initializer = make_node (CONSTRUCTOR); /* Mark it with TREE_HAS_CONSTRUCTOR. This should not be necessary, but check_initializer depends upon it, for now. */ TREE_HAS_CONSTRUCTOR (initializer) = 1; /* If it's not a `}', then there is a non-trivial initializer. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_BRACE)) { /* Parse the initializer list. */ CONSTRUCTOR_ELTS (initializer) = cp_parser_initializer_list (parser, non_constant_p); /* A trailing `,' token is allowed. */ if (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)) cp_lexer_consume_token (parser->lexer); } /* Now, there should be a trailing `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); } return initializer; } /* Parse an initializer-list. initializer-list: initializer-clause initializer-list , initializer-clause GNU Extension: initializer-list: identifier : initializer-clause initializer-list, identifier : initializer-clause Returns a TREE_LIST. The TREE_VALUE of each node is an expression for the initializer. If the TREE_PURPOSE is non-NULL, it is the IDENTIFIER_NODE naming the field to initialize. NON_CONSTANT_P is as for cp_parser_initializer. */ static tree cp_parser_initializer_list (cp_parser* parser, bool* non_constant_p) { tree initializers = NULL_TREE; /* Assume all of the expressions are constant. */ *non_constant_p = false; /* Parse the rest of the list. */ while (true) { cp_token *token; tree identifier; tree initializer; bool clause_non_constant_p; /* If the next token is an identifier and the following one is a colon, we are looking at the GNU designated-initializer syntax. */ if (cp_parser_allow_gnu_extensions_p (parser) && cp_lexer_next_token_is (parser->lexer, CPP_NAME) && cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_COLON) { /* Consume the identifier. */ identifier = cp_lexer_consume_token (parser->lexer)->value; /* Consume the `:'. */ cp_lexer_consume_token (parser->lexer); } else identifier = NULL_TREE; /* Parse the initializer. */ initializer = cp_parser_initializer_clause (parser, &clause_non_constant_p); /* If any clause is non-constant, so is the entire initializer. */ if (clause_non_constant_p) *non_constant_p = true; /* Add it to the list. */ initializers = tree_cons (identifier, initializer, initializers); /* If the next token is not a comma, we have reached the end of the list. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) break; /* Peek at the next token. */ token = cp_lexer_peek_nth_token (parser->lexer, 2); /* If the next token is a `}', then we're still done. An initializer-clause can have a trailing `,' after the initializer-list and before the closing `}'. */ if (token->type == CPP_CLOSE_BRACE) break; /* Consume the `,' token. */ cp_lexer_consume_token (parser->lexer); } /* The initializers were built up in reverse order, so we need to reverse them now. */ return nreverse (initializers); } /* Classes [gram.class] */ /* Parse a class-name. class-name: identifier template-id TYPENAME_KEYWORD_P is true iff the `typename' keyword has been used to indicate that names looked up in dependent types should be assumed to be types. TEMPLATE_KEYWORD_P is true iff the `template' keyword has been used to indicate that the name that appears next is a template. TYPE_P is true iff the next name should be treated as class-name, even if it is declared to be some other kind of name as well. If CHECK_DEPENDENCY_P is FALSE, names are looked up in dependent scopes. If CLASS_HEAD_P is TRUE, this class is the class being defined in a class-head. Returns the TYPE_DECL representing the class. */ static tree cp_parser_class_name (cp_parser *parser, bool typename_keyword_p, bool template_keyword_p, bool type_p, bool check_dependency_p, bool class_head_p, bool is_declaration) { tree decl; tree scope; bool typename_p; cp_token *token; /* All class-names start with an identifier. */ token = cp_lexer_peek_token (parser->lexer); if (token->type != CPP_NAME && token->type != CPP_TEMPLATE_ID) { cp_parser_error (parser, "expected class-name"); return error_mark_node; } /* PARSER->SCOPE can be cleared when parsing the template-arguments to a template-id, so we save it here. */ scope = parser->scope; if (scope == error_mark_node) return error_mark_node; /* Any name names a type if we're following the `typename' keyword in a qualified name where the enclosing scope is type-dependent. */ typename_p = (typename_keyword_p && scope && TYPE_P (scope) && dependent_type_p (scope)); /* Handle the common case (an identifier, but not a template-id) efficiently. */ if (token->type == CPP_NAME && !cp_parser_nth_token_starts_template_argument_list_p (parser, 2)) { tree identifier; /* Look for the identifier. */ identifier = cp_parser_identifier (parser); /* If the next token isn't an identifier, we are certainly not looking at a class-name. */ if (identifier == error_mark_node) decl = error_mark_node; /* If we know this is a type-name, there's no need to look it up. */ else if (typename_p) decl = identifier; else { /* If the next token is a `::', then the name must be a type name. [basic.lookup.qual] During the lookup for a name preceding the :: scope resolution operator, object, function, and enumerator names are ignored. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)) type_p = true; /* Look up the name. */ decl = cp_parser_lookup_name (parser, identifier, type_p, /*is_template=*/false, /*is_namespace=*/false, check_dependency_p); } } else { /* Try a template-id. */ decl = cp_parser_template_id (parser, template_keyword_p, check_dependency_p, is_declaration); if (decl == error_mark_node) return error_mark_node; } decl = cp_parser_maybe_treat_template_as_class (decl, class_head_p); /* If this is a typename, create a TYPENAME_TYPE. */ if (typename_p && decl != error_mark_node) { decl = make_typename_type (scope, decl, /*complain=*/1); if (decl != error_mark_node) decl = TYPE_NAME (decl); } /* Check to see that it is really the name of a class. */ if (TREE_CODE (decl) == TEMPLATE_ID_EXPR && TREE_CODE (TREE_OPERAND (decl, 0)) == IDENTIFIER_NODE && cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)) /* Situations like this: template struct A { typename T::template X::I i; }; are problematic. Is `T::template X' a class-name? The standard does not seem to be definitive, but there is no other valid interpretation of the following `::'. Therefore, those names are considered class-names. */ decl = TYPE_NAME (make_typename_type (scope, decl, tf_error)); else if (decl == error_mark_node || TREE_CODE (decl) != TYPE_DECL || !IS_AGGR_TYPE (TREE_TYPE (decl))) { cp_parser_error (parser, "expected class-name"); return error_mark_node; } return decl; } /* Parse a class-specifier. class-specifier: class-head { member-specification [opt] } Returns the TREE_TYPE representing the class. */ static tree cp_parser_class_specifier (cp_parser* parser) { cp_token *token; tree type; tree attributes; int has_trailing_semicolon; bool nested_name_specifier_p; unsigned saved_num_template_parameter_lists; bool pop_p = false; push_deferring_access_checks (dk_no_deferred); /* Parse the class-head. */ type = cp_parser_class_head (parser, &nested_name_specifier_p, &attributes); /* If the class-head was a semantic disaster, skip the entire body of the class. */ if (!type) { cp_parser_skip_to_end_of_block_or_statement (parser); pop_deferring_access_checks (); return error_mark_node; } /* Look for the `{'. */ if (!cp_parser_require (parser, CPP_OPEN_BRACE, "`{'")) { pop_deferring_access_checks (); return error_mark_node; } /* Issue an error message if type-definitions are forbidden here. */ cp_parser_check_type_definition (parser); /* Remember that we are defining one more class. */ ++parser->num_classes_being_defined; /* Inside the class, surrounding template-parameter-lists do not apply. */ saved_num_template_parameter_lists = parser->num_template_parameter_lists; parser->num_template_parameter_lists = 0; /* Start the class. */ if (nested_name_specifier_p) pop_p = push_scope (CP_DECL_CONTEXT (TYPE_MAIN_DECL (type))); type = begin_class_definition (type); if (type == error_mark_node) /* If the type is erroneous, skip the entire body of the class. */ cp_parser_skip_to_closing_brace (parser); else /* Parse the member-specification. */ cp_parser_member_specification_opt (parser); /* Look for the trailing `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); /* We get better error messages by noticing a common problem: a missing trailing `;'. */ token = cp_lexer_peek_token (parser->lexer); has_trailing_semicolon = (token->type == CPP_SEMICOLON); /* Look for trailing attributes to apply to this class. */ if (cp_parser_allow_gnu_extensions_p (parser)) { tree sub_attr = cp_parser_attributes_opt (parser); attributes = chainon (attributes, sub_attr); } if (type != error_mark_node) type = finish_struct (type, attributes); if (pop_p) pop_scope (CP_DECL_CONTEXT (TYPE_MAIN_DECL (type))); /* If this class is not itself within the scope of another class, then we need to parse the bodies of all of the queued function definitions. Note that the queued functions defined in a class are not always processed immediately following the class-specifier for that class. Consider: struct A { struct B { void f() { sizeof (A); } }; }; If `f' were processed before the processing of `A' were completed, there would be no way to compute the size of `A'. Note that the nesting we are interested in here is lexical -- not the semantic nesting given by TYPE_CONTEXT. In particular, for: struct A { struct B; }; struct A::B { void f() { } }; there is no need to delay the parsing of `A::B::f'. */ if (--parser->num_classes_being_defined == 0) { tree queue_entry; tree fn; /* In a first pass, parse default arguments to the functions. Then, in a second pass, parse the bodies of the functions. This two-phased approach handles cases like: struct S { void f() { g(); } void g(int i = 3); }; */ for (TREE_PURPOSE (parser->unparsed_functions_queues) = nreverse (TREE_PURPOSE (parser->unparsed_functions_queues)); (queue_entry = TREE_PURPOSE (parser->unparsed_functions_queues)); TREE_PURPOSE (parser->unparsed_functions_queues) = TREE_CHAIN (TREE_PURPOSE (parser->unparsed_functions_queues))) { fn = TREE_VALUE (queue_entry); /* Make sure that any template parameters are in scope. */ maybe_begin_member_template_processing (fn); /* If there are default arguments that have not yet been processed, take care of them now. */ cp_parser_late_parsing_default_args (parser, fn); /* Remove any template parameters from the symbol table. */ maybe_end_member_template_processing (); } /* Now parse the body of the functions. */ for (TREE_VALUE (parser->unparsed_functions_queues) = nreverse (TREE_VALUE (parser->unparsed_functions_queues)); (queue_entry = TREE_VALUE (parser->unparsed_functions_queues)); TREE_VALUE (parser->unparsed_functions_queues) = TREE_CHAIN (TREE_VALUE (parser->unparsed_functions_queues))) { /* Figure out which function we need to process. */ fn = TREE_VALUE (queue_entry); /* A hack to prevent garbage collection. */ function_depth++; /* Parse the function. */ cp_parser_late_parsing_for_member (parser, fn); function_depth--; } } /* Put back any saved access checks. */ pop_deferring_access_checks (); /* Restore the count of active template-parameter-lists. */ parser->num_template_parameter_lists = saved_num_template_parameter_lists; return type; } /* Parse a class-head. class-head: class-key identifier [opt] base-clause [opt] class-key nested-name-specifier identifier base-clause [opt] class-key nested-name-specifier [opt] template-id base-clause [opt] GNU Extensions: class-key attributes identifier [opt] base-clause [opt] class-key attributes nested-name-specifier identifier base-clause [opt] class-key attributes nested-name-specifier [opt] template-id base-clause [opt] Returns the TYPE of the indicated class. Sets *NESTED_NAME_SPECIFIER_P to TRUE iff one of the productions involving a nested-name-specifier was used, and FALSE otherwise. Returns NULL_TREE if the class-head is syntactically valid, but semantically invalid in a way that means we should skip the entire body of the class. */ static tree cp_parser_class_head (cp_parser* parser, bool* nested_name_specifier_p, tree *attributes_p) { cp_token *token; tree nested_name_specifier; enum tag_types class_key; tree id = NULL_TREE; tree type = NULL_TREE; tree attributes; bool template_id_p = false; bool qualified_p = false; bool invalid_nested_name_p = false; bool invalid_explicit_specialization_p = false; bool pop_p = false; unsigned num_templates; /* Assume no nested-name-specifier will be present. */ *nested_name_specifier_p = false; /* Assume no template parameter lists will be used in defining the type. */ num_templates = 0; /* Look for the class-key. */ class_key = cp_parser_class_key (parser); if (class_key == none_type) return error_mark_node; /* Parse the attributes. */ attributes = cp_parser_attributes_opt (parser); /* If the next token is `::', that is invalid -- but sometimes people do try to write: struct ::S {}; Handle this gracefully by accepting the extra qualifier, and then issuing an error about it later if this really is a class-head. If it turns out just to be an elaborated type specifier, remain silent. */ if (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false)) qualified_p = true; push_deferring_access_checks (dk_no_check); /* Determine the name of the class. Begin by looking for an optional nested-name-specifier. */ nested_name_specifier = cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/false, /*type_p=*/false, /*is_declaration=*/false); /* If there was a nested-name-specifier, then there *must* be an identifier. */ if (nested_name_specifier) { /* Although the grammar says `identifier', it really means `class-name' or `template-name'. You are only allowed to define a class that has already been declared with this syntax. The proposed resolution for Core Issue 180 says that whever you see `class T::X' you should treat `X' as a type-name. It is OK to define an inaccessible class; for example: class A { class B; }; class A::B {}; We do not know if we will see a class-name, or a template-name. We look for a class-name first, in case the class-name is a template-id; if we looked for the template-name first we would stop after the template-name. */ cp_parser_parse_tentatively (parser); type = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, /*type_p=*/true, /*check_dependency_p=*/false, /*class_head_p=*/true, /*is_declaration=*/false); /* If that didn't work, ignore the nested-name-specifier. */ if (!cp_parser_parse_definitely (parser)) { invalid_nested_name_p = true; id = cp_parser_identifier (parser); if (id == error_mark_node) id = NULL_TREE; } /* If we could not find a corresponding TYPE, treat this declaration like an unqualified declaration. */ if (type == error_mark_node) nested_name_specifier = NULL_TREE; /* Otherwise, count the number of templates used in TYPE and its containing scopes. */ else { tree scope; for (scope = TREE_TYPE (type); scope && TREE_CODE (scope) != NAMESPACE_DECL; scope = (TYPE_P (scope) ? TYPE_CONTEXT (scope) : DECL_CONTEXT (scope))) if (TYPE_P (scope) && CLASS_TYPE_P (scope) && CLASSTYPE_TEMPLATE_INFO (scope) && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (scope)) && !CLASSTYPE_TEMPLATE_SPECIALIZATION (scope)) ++num_templates; } } /* Otherwise, the identifier is optional. */ else { /* We don't know whether what comes next is a template-id, an identifier, or nothing at all. */ cp_parser_parse_tentatively (parser); /* Check for a template-id. */ id = cp_parser_template_id (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, /*is_declaration=*/true); /* If that didn't work, it could still be an identifier. */ if (!cp_parser_parse_definitely (parser)) { if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)) id = cp_parser_identifier (parser); else id = NULL_TREE; } else { template_id_p = true; ++num_templates; } } pop_deferring_access_checks (); if (id) cp_parser_check_for_invalid_template_id (parser, id); /* If it's not a `:' or a `{' then we can't really be looking at a class-head, since a class-head only appears as part of a class-specifier. We have to detect this situation before calling xref_tag, since that has irreversible side-effects. */ if (!cp_parser_next_token_starts_class_definition_p (parser)) { cp_parser_error (parser, "expected `{' or `:'"); return error_mark_node; } /* At this point, we're going ahead with the class-specifier, even if some other problem occurs. */ cp_parser_commit_to_tentative_parse (parser); /* Issue the error about the overly-qualified name now. */ if (qualified_p) cp_parser_error (parser, "global qualification of class name is invalid"); else if (invalid_nested_name_p) cp_parser_error (parser, "qualified name does not name a class"); else if (nested_name_specifier) { tree scope; /* Figure out in what scope the declaration is being placed. */ scope = current_scope (); if (!scope) scope = current_namespace; /* If that scope does not contain the scope in which the class was originally declared, the program is invalid. */ if (scope && !is_ancestor (scope, nested_name_specifier)) { error ("declaration of `%D' in `%D' which does not " "enclose `%D'", type, scope, nested_name_specifier); type = NULL_TREE; goto done; } /* [dcl.meaning] A declarator-id shall not be qualified exception of the definition of a ... nested class outside of its class ... [or] a the definition or explicit instantiation of a class member of a namespace outside of its namespace. */ if (scope == nested_name_specifier) { pedwarn ("extra qualification ignored"); nested_name_specifier = NULL_TREE; num_templates = 0; } } /* An explicit-specialization must be preceded by "template <>". If it is not, try to recover gracefully. */ if (at_namespace_scope_p () && parser->num_template_parameter_lists == 0 && template_id_p) { error ("an explicit specialization must be preceded by 'template <>'"); invalid_explicit_specialization_p = true; /* Take the same action that would have been taken by cp_parser_explicit_specialization. */ ++parser->num_template_parameter_lists; begin_specialization (); } /* There must be no "return" statements between this point and the end of this function; set "type "to the correct return value and use "goto done;" to return. */ /* Make sure that the right number of template parameters were present. */ if (!cp_parser_check_template_parameters (parser, num_templates)) { /* If something went wrong, there is no point in even trying to process the class-definition. */ type = NULL_TREE; goto done; } /* Look up the type. */ if (template_id_p) { type = TREE_TYPE (id); maybe_process_partial_specialization (type); } else if (!nested_name_specifier) { /* If the class was unnamed, create a dummy name. */ if (!id) id = make_anon_name (); type = xref_tag (class_key, id, /*globalize=*/false, parser->num_template_parameter_lists); } else { tree class_type; bool pop_p = false; /* Given: template struct S { struct T }; template struct S::T { }; we will get a TYPENAME_TYPE when processing the definition of `S::T'. We need to resolve it to the actual type before we try to define it. */ if (TREE_CODE (TREE_TYPE (type)) == TYPENAME_TYPE) { class_type = resolve_typename_type (TREE_TYPE (type), /*only_current_p=*/false); if (class_type != error_mark_node) type = TYPE_NAME (class_type); else { cp_parser_error (parser, "could not resolve typename type"); type = error_mark_node; } } maybe_process_partial_specialization (TREE_TYPE (type)); class_type = current_class_type; /* Enter the scope indicated by the nested-name-specifier. */ if (nested_name_specifier) pop_p = push_scope (nested_name_specifier); /* Get the canonical version of this type. */ type = TYPE_MAIN_DECL (TREE_TYPE (type)); if (PROCESSING_REAL_TEMPLATE_DECL_P () && !CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (type))) type = push_template_decl (type); type = TREE_TYPE (type); if (nested_name_specifier) { *nested_name_specifier_p = true; if (pop_p) pop_scope (nested_name_specifier); } } /* Indicate whether this class was declared as a `class' or as a `struct'. */ if (TREE_CODE (type) == RECORD_TYPE) CLASSTYPE_DECLARED_CLASS (type) = (class_key == class_type); cp_parser_check_class_key (class_key, type); /* Enter the scope containing the class; the names of base classes should be looked up in that context. For example, given: struct A { struct B {}; struct C; }; struct A::C : B {}; is valid. */ if (nested_name_specifier) pop_p = push_scope (nested_name_specifier); /* Now, look for the base-clause. */ token = cp_lexer_peek_token (parser->lexer); if (token->type == CPP_COLON) { tree bases; /* Get the list of base-classes. */ bases = cp_parser_base_clause (parser); /* Process them. */ xref_basetypes (type, bases); } /* Leave the scope given by the nested-name-specifier. We will enter the class scope itself while processing the members. */ if (pop_p) pop_scope (nested_name_specifier); done: if (invalid_explicit_specialization_p) { end_specialization (); --parser->num_template_parameter_lists; } *attributes_p = attributes; return type; } /* Parse a class-key. class-key: class struct union Returns the kind of class-key specified, or none_type to indicate error. */ static enum tag_types cp_parser_class_key (cp_parser* parser) { cp_token *token; enum tag_types tag_type; /* Look for the class-key. */ token = cp_parser_require (parser, CPP_KEYWORD, "class-key"); if (!token) return none_type; /* Check to see if the TOKEN is a class-key. */ tag_type = cp_parser_token_is_class_key (token); if (!tag_type) cp_parser_error (parser, "expected class-key"); return tag_type; } /* Parse an (optional) member-specification. member-specification: member-declaration member-specification [opt] access-specifier : member-specification [opt] */ static void cp_parser_member_specification_opt (cp_parser* parser) { while (true) { cp_token *token; enum rid keyword; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's a `}', or EOF then we've seen all the members. */ if (token->type == CPP_CLOSE_BRACE || token->type == CPP_EOF) break; /* See if this token is a keyword. */ keyword = token->keyword; switch (keyword) { case RID_PUBLIC: case RID_PROTECTED: case RID_PRIVATE: /* Consume the access-specifier. */ cp_lexer_consume_token (parser->lexer); /* Remember which access-specifier is active. */ current_access_specifier = token->value; /* Look for the `:'. */ cp_parser_require (parser, CPP_COLON, "`:'"); break; default: /* Otherwise, the next construction must be a member-declaration. */ cp_parser_member_declaration (parser); } } } /* Parse a member-declaration. member-declaration: decl-specifier-seq [opt] member-declarator-list [opt] ; function-definition ; [opt] :: [opt] nested-name-specifier template [opt] unqualified-id ; using-declaration template-declaration member-declarator-list: member-declarator member-declarator-list , member-declarator member-declarator: declarator pure-specifier [opt] declarator constant-initializer [opt] identifier [opt] : constant-expression GNU Extensions: member-declaration: __extension__ member-declaration member-declarator: declarator attributes [opt] pure-specifier [opt] declarator attributes [opt] constant-initializer [opt] identifier [opt] attributes [opt] : constant-expression */ static void cp_parser_member_declaration (cp_parser* parser) { tree decl_specifiers; tree prefix_attributes; tree decl; int declares_class_or_enum; bool friend_p; cp_token *token; int saved_pedantic; /* Check for the `__extension__' keyword. */ if (cp_parser_extension_opt (parser, &saved_pedantic)) { /* Recurse. */ cp_parser_member_declaration (parser); /* Restore the old value of the PEDANTIC flag. */ pedantic = saved_pedantic; return; } /* Check for a template-declaration. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_TEMPLATE)) { /* Parse the template-declaration. */ cp_parser_template_declaration (parser, /*member_p=*/true); return; } /* Check for a using-declaration. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_USING)) { /* Parse the using-declaration. */ cp_parser_using_declaration (parser); return; } /* Parse the decl-specifier-seq. */ decl_specifiers = cp_parser_decl_specifier_seq (parser, CP_PARSER_FLAGS_OPTIONAL, &prefix_attributes, &declares_class_or_enum); /* Check for an invalid type-name. */ if (cp_parser_diagnose_invalid_type_name (parser)) return; /* If there is no declarator, then the decl-specifier-seq should specify a type. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON)) { /* If there was no decl-specifier-seq, and the next token is a `;', then we have something like: struct S { ; }; [class.mem] Each member-declaration shall declare at least one member name of the class. */ if (!decl_specifiers) { if (pedantic) pedwarn ("extra semicolon"); } else { tree type; /* See if this declaration is a friend. */ friend_p = cp_parser_friend_p (decl_specifiers); /* If there were decl-specifiers, check to see if there was a class-declaration. */ type = check_tag_decl (decl_specifiers); /* Nested classes have already been added to the class, but a `friend' needs to be explicitly registered. */ if (friend_p) { /* If the `friend' keyword was present, the friend must be introduced with a class-key. */ if (!declares_class_or_enum) error ("a class-key must be used when declaring a friend"); /* In this case: template struct A { friend struct A::B; }; A::B will be represented by a TYPENAME_TYPE, and therefore not recognized by check_tag_decl. */ if (!type) { tree specifier; for (specifier = decl_specifiers; specifier; specifier = TREE_CHAIN (specifier)) { tree s = TREE_VALUE (specifier); if (TREE_CODE (s) == IDENTIFIER_NODE) get_global_value_if_present (s, &type); if (TREE_CODE (s) == TYPE_DECL) s = TREE_TYPE (s); if (TYPE_P (s)) { type = s; break; } } } if (!type || !TYPE_P (type)) error ("friend declaration does not name a class or " "function"); else make_friend_class (current_class_type, type, /*complain=*/true); } /* If there is no TYPE, an error message will already have been issued. */ else if (!type) ; /* An anonymous aggregate has to be handled specially; such a declaration really declares a data member (with a particular type), as opposed to a nested class. */ else if (ANON_AGGR_TYPE_P (type)) { /* Remove constructors and such from TYPE, now that we know it is an anonymous aggregate. */ fixup_anonymous_aggr (type); /* And make the corresponding data member. */ decl = build_decl (FIELD_DECL, NULL_TREE, type); /* Add it to the class. */ finish_member_declaration (decl); } else cp_parser_check_access_in_redeclaration (TYPE_NAME (type)); } } else { /* See if these declarations will be friends. */ friend_p = cp_parser_friend_p (decl_specifiers); /* Keep going until we hit the `;' at the end of the declaration. */ while (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) { tree attributes = NULL_TREE; tree first_attribute; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Check for a bitfield declaration. */ if (token->type == CPP_COLON || (token->type == CPP_NAME && cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_COLON)) { tree identifier; tree width; /* Get the name of the bitfield. Note that we cannot just check TOKEN here because it may have been invalidated by the call to cp_lexer_peek_nth_token above. */ if (cp_lexer_peek_token (parser->lexer)->type != CPP_COLON) identifier = cp_parser_identifier (parser); else identifier = NULL_TREE; /* Consume the `:' token. */ cp_lexer_consume_token (parser->lexer); /* Get the width of the bitfield. */ width = cp_parser_constant_expression (parser, /*allow_non_constant=*/false, NULL); /* Look for attributes that apply to the bitfield. */ attributes = cp_parser_attributes_opt (parser); /* Remember which attributes are prefix attributes and which are not. */ first_attribute = attributes; /* Combine the attributes. */ attributes = chainon (prefix_attributes, attributes); /* Create the bitfield declaration. */ decl = grokbitfield (identifier, decl_specifiers, width); /* Apply the attributes. */ cplus_decl_attributes (&decl, attributes, /*flags=*/0); } else { tree declarator; tree initializer; tree asm_specification; int ctor_dtor_or_conv_p; /* Parse the declarator. */ declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_NAMED, &ctor_dtor_or_conv_p, /*parenthesized_p=*/NULL); /* If something went wrong parsing the declarator, make sure that we at least consume some tokens. */ if (declarator == error_mark_node) { /* Skip to the end of the statement. */ cp_parser_skip_to_end_of_statement (parser); /* If the next token is not a semicolon, that is probably because we just skipped over the body of a function. So, we consume a semicolon if present, but do not issue an error message if it is not present. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON)) cp_lexer_consume_token (parser->lexer); return; } cp_parser_check_for_definition_in_return_type (declarator, declares_class_or_enum); /* Look for an asm-specification. */ asm_specification = cp_parser_asm_specification_opt (parser); /* Look for attributes that apply to the declaration. */ attributes = cp_parser_attributes_opt (parser); /* Remember which attributes are prefix attributes and which are not. */ first_attribute = attributes; /* Combine the attributes. */ attributes = chainon (prefix_attributes, attributes); /* If it's an `=', then we have a constant-initializer or a pure-specifier. It is not correct to parse the initializer before registering the member declaration since the member declaration should be in scope while its initializer is processed. However, the rest of the front end does not yet provide an interface that allows us to handle this correctly. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EQ)) { /* In [class.mem]: A pure-specifier shall be used only in the declaration of a virtual function. A member-declarator can contain a constant-initializer only if it declares a static member of integral or enumeration type. Therefore, if the DECLARATOR is for a function, we look for a pure-specifier; otherwise, we look for a constant-initializer. When we call `grokfield', it will perform more stringent semantics checks. */ if (TREE_CODE (declarator) == CALL_EXPR) initializer = cp_parser_pure_specifier (parser); else /* Parse the initializer. */ initializer = cp_parser_constant_initializer (parser); } /* Otherwise, there is no initializer. */ else initializer = NULL_TREE; /* See if we are probably looking at a function definition. We are certainly not looking at at a member-declarator. Calling `grokfield' has side-effects, so we must not do it unless we are sure that we are looking at a member-declarator. */ if (cp_parser_token_starts_function_definition_p (cp_lexer_peek_token (parser->lexer))) { /* The grammar does not allow a pure-specifier to be used when a member function is defined. (It is possible that this fact is an oversight in the standard, since a pure function may be defined outside of the class-specifier. */ if (initializer) error ("pure-specifier on function-definition"); decl = cp_parser_save_member_function_body (parser, decl_specifiers, declarator, attributes); /* If the member was not a friend, declare it here. */ if (!friend_p) finish_member_declaration (decl); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If the next token is a semicolon, consume it. */ if (token->type == CPP_SEMICOLON) cp_lexer_consume_token (parser->lexer); return; } else { /* Create the declaration. */ decl = grokfield (declarator, decl_specifiers, initializer, asm_specification, attributes); /* Any initialization must have been from a constant-expression. */ if (decl && TREE_CODE (decl) == VAR_DECL && initializer) DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = 1; } } /* Reset PREFIX_ATTRIBUTES. */ while (attributes && TREE_CHAIN (attributes) != first_attribute) attributes = TREE_CHAIN (attributes); if (attributes) TREE_CHAIN (attributes) = NULL_TREE; /* If there is any qualification still in effect, clear it now; we will be starting fresh with the next declarator. */ parser->scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; parser->object_scope = NULL_TREE; /* If it's a `,', then there are more declarators. */ if (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)) cp_lexer_consume_token (parser->lexer); /* If the next token isn't a `;', then we have a parse error. */ else if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) { cp_parser_error (parser, "expected `;'"); /* Skip tokens until we find a `;'. */ cp_parser_skip_to_end_of_statement (parser); break; } if (decl) { /* Add DECL to the list of members. */ if (!friend_p) finish_member_declaration (decl); if (TREE_CODE (decl) == FUNCTION_DECL) cp_parser_save_default_args (parser, decl); } } } cp_parser_require (parser, CPP_SEMICOLON, "`;'"); } /* Parse a pure-specifier. pure-specifier: = 0 Returns INTEGER_ZERO_NODE if a pure specifier is found. Otherwise, ERROR_MARK_NODE is returned. */ static tree cp_parser_pure_specifier (cp_parser* parser) { cp_token *token; /* Look for the `=' token. */ if (!cp_parser_require (parser, CPP_EQ, "`='")) return error_mark_node; /* Look for the `0' token. */ token = cp_parser_require (parser, CPP_NUMBER, "`0'"); /* Unfortunately, this will accept `0L' and `0x00' as well. We need to get information from the lexer about how the number was spelled in order to fix this problem. */ if (!token || !integer_zerop (token->value)) return error_mark_node; return integer_zero_node; } /* Parse a constant-initializer. constant-initializer: = constant-expression Returns a representation of the constant-expression. */ static tree cp_parser_constant_initializer (cp_parser* parser) { /* Look for the `=' token. */ if (!cp_parser_require (parser, CPP_EQ, "`='")) return error_mark_node; /* It is invalid to write: struct S { static const int i = { 7 }; }; */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE)) { cp_parser_error (parser, "a brace-enclosed initializer is not allowed here"); /* Consume the opening brace. */ cp_lexer_consume_token (parser->lexer); /* Skip the initializer. */ cp_parser_skip_to_closing_brace (parser); /* Look for the trailing `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); return error_mark_node; } return cp_parser_constant_expression (parser, /*allow_non_constant=*/false, NULL); } /* Derived classes [gram.class.derived] */ /* Parse a base-clause. base-clause: : base-specifier-list base-specifier-list: base-specifier base-specifier-list , base-specifier Returns a TREE_LIST representing the base-classes, in the order in which they were declared. The representation of each node is as described by cp_parser_base_specifier. In the case that no bases are specified, this function will return NULL_TREE, not ERROR_MARK_NODE. */ static tree cp_parser_base_clause (cp_parser* parser) { tree bases = NULL_TREE; /* Look for the `:' that begins the list. */ cp_parser_require (parser, CPP_COLON, "`:'"); /* Scan the base-specifier-list. */ while (true) { cp_token *token; tree base; /* Look for the base-specifier. */ base = cp_parser_base_specifier (parser); /* Add BASE to the front of the list. */ if (base != error_mark_node) { TREE_CHAIN (base) = bases; bases = base; } /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's not a comma, then the list is complete. */ if (token->type != CPP_COMMA) break; /* Consume the `,'. */ cp_lexer_consume_token (parser->lexer); } /* PARSER->SCOPE may still be non-NULL at this point, if the last base class had a qualified name. However, the next name that appears is certainly not qualified. */ parser->scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; parser->object_scope = NULL_TREE; return nreverse (bases); } /* Parse a base-specifier. base-specifier: :: [opt] nested-name-specifier [opt] class-name virtual access-specifier [opt] :: [opt] nested-name-specifier [opt] class-name access-specifier virtual [opt] :: [opt] nested-name-specifier [opt] class-name Returns a TREE_LIST. The TREE_PURPOSE will be one of ACCESS_{DEFAULT,PUBLIC,PROTECTED,PRIVATE}_[VIRTUAL]_NODE to indicate the specifiers provided. The TREE_VALUE will be a TYPE (or the ERROR_MARK_NODE) indicating the type that was specified. */ static tree cp_parser_base_specifier (cp_parser* parser) { cp_token *token; bool done = false; bool virtual_p = false; bool duplicate_virtual_error_issued_p = false; bool duplicate_access_error_issued_p = false; bool class_scope_p, template_p; tree access = access_default_node; tree type; /* Process the optional `virtual' and `access-specifier'. */ while (!done) { /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Process `virtual'. */ switch (token->keyword) { case RID_VIRTUAL: /* If `virtual' appears more than once, issue an error. */ if (virtual_p && !duplicate_virtual_error_issued_p) { cp_parser_error (parser, "`virtual' specified more than once in base-specified"); duplicate_virtual_error_issued_p = true; } virtual_p = true; /* Consume the `virtual' token. */ cp_lexer_consume_token (parser->lexer); break; case RID_PUBLIC: case RID_PROTECTED: case RID_PRIVATE: /* If more than one access specifier appears, issue an error. */ if (access != access_default_node && !duplicate_access_error_issued_p) { cp_parser_error (parser, "more than one access specifier in base-specified"); duplicate_access_error_issued_p = true; } access = ridpointers[(int) token->keyword]; /* Consume the access-specifier. */ cp_lexer_consume_token (parser->lexer); break; default: done = true; break; } } /* It is not uncommon to see programs mechanically, errouneously, use the 'typename' keyword to denote (dependent) qualified types as base classes. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_TYPENAME)) { if (!processing_template_decl) error ("keyword `typename' not allowed outside of templates"); else error ("keyword `typename' not allowed in this context " "(the base class is implicitly a type)"); cp_lexer_consume_token (parser->lexer); } /* Look for the optional `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* Look for the nested-name-specifier. The simplest way to implement: [temp.res] The keyword `typename' is not permitted in a base-specifier or mem-initializer; in these contexts a qualified name that depends on a template-parameter is implicitly assumed to be a type name. is to pretend that we have seen the `typename' keyword at this point. */ cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/true, /*check_dependency_p=*/true, /*type_p=*/true, /*is_declaration=*/true); /* If the base class is given by a qualified name, assume that names we see are type names or templates, as appropriate. */ class_scope_p = (parser->scope && TYPE_P (parser->scope)); template_p = class_scope_p && cp_parser_optional_template_keyword (parser); /* Finally, look for the class-name. */ type = cp_parser_class_name (parser, class_scope_p, template_p, /*type_p=*/true, /*check_dependency_p=*/true, /*class_head_p=*/false, /*is_declaration=*/true); if (type == error_mark_node) return error_mark_node; return finish_base_specifier (TREE_TYPE (type), access, virtual_p); } /* Exception handling [gram.exception] */ /* Parse an (optional) exception-specification. exception-specification: throw ( type-id-list [opt] ) Returns a TREE_LIST representing the exception-specification. The TREE_VALUE of each node is a type. */ static tree cp_parser_exception_specification_opt (cp_parser* parser) { cp_token *token; tree type_id_list; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's not `throw', then there's no exception-specification. */ if (!cp_parser_is_keyword (token, RID_THROW)) return NULL_TREE; /* Consume the `throw'. */ cp_lexer_consume_token (parser->lexer); /* Look for the `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's not a `)', then there is a type-id-list. */ if (token->type != CPP_CLOSE_PAREN) { const char *saved_message; /* Types may not be defined in an exception-specification. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in an exception-specification"; /* Parse the type-id-list. */ type_id_list = cp_parser_type_id_list (parser); /* Restore the saved message. */ parser->type_definition_forbidden_message = saved_message; } else type_id_list = empty_except_spec; /* Look for the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); return type_id_list; } /* Parse an (optional) type-id-list. type-id-list: type-id type-id-list , type-id Returns a TREE_LIST. The TREE_VALUE of each node is a TYPE, in the order that the types were presented. */ static tree cp_parser_type_id_list (cp_parser* parser) { tree types = NULL_TREE; while (true) { cp_token *token; tree type; /* Get the next type-id. */ type = cp_parser_type_id (parser); /* Add it to the list. */ types = add_exception_specifier (types, type, /*complain=*/1); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it is not a `,', we are done. */ if (token->type != CPP_COMMA) break; /* Consume the `,'. */ cp_lexer_consume_token (parser->lexer); } return nreverse (types); } /* Parse a try-block. try-block: try compound-statement handler-seq */ static tree cp_parser_try_block (cp_parser* parser) { tree try_block; cp_parser_require_keyword (parser, RID_TRY, "`try'"); try_block = begin_try_block (); cp_parser_compound_statement (parser, false); finish_try_block (try_block); cp_parser_handler_seq (parser); finish_handler_sequence (try_block); return try_block; } /* Parse a function-try-block. function-try-block: try ctor-initializer [opt] function-body handler-seq */ static bool cp_parser_function_try_block (cp_parser* parser) { tree try_block; bool ctor_initializer_p; /* Look for the `try' keyword. */ if (!cp_parser_require_keyword (parser, RID_TRY, "`try'")) return false; /* Let the rest of the front-end know where we are. */ try_block = begin_function_try_block (); /* Parse the function-body. */ ctor_initializer_p = cp_parser_ctor_initializer_opt_and_function_body (parser); /* We're done with the `try' part. */ finish_function_try_block (try_block); /* Parse the handlers. */ cp_parser_handler_seq (parser); /* We're done with the handlers. */ finish_function_handler_sequence (try_block); return ctor_initializer_p; } /* Parse a handler-seq. handler-seq: handler handler-seq [opt] */ static void cp_parser_handler_seq (cp_parser* parser) { while (true) { cp_token *token; /* Parse the handler. */ cp_parser_handler (parser); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's not `catch' then there are no more handlers. */ if (!cp_parser_is_keyword (token, RID_CATCH)) break; } } /* Parse a handler. handler: catch ( exception-declaration ) compound-statement */ static void cp_parser_handler (cp_parser* parser) { tree handler; tree declaration; cp_parser_require_keyword (parser, RID_CATCH, "`catch'"); handler = begin_handler (); cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); declaration = cp_parser_exception_declaration (parser); finish_handler_parms (declaration, handler); cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); cp_parser_compound_statement (parser, false); finish_handler (handler); } /* Parse an exception-declaration. exception-declaration: type-specifier-seq declarator type-specifier-seq abstract-declarator type-specifier-seq ... Returns a VAR_DECL for the declaration, or NULL_TREE if the ellipsis variant is used. */ static tree cp_parser_exception_declaration (cp_parser* parser) { tree type_specifiers; tree declarator; const char *saved_message; /* If it's an ellipsis, it's easy to handle. */ if (cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS)) { /* Consume the `...' token. */ cp_lexer_consume_token (parser->lexer); return NULL_TREE; } /* Types may not be defined in exception-declarations. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in exception-declarations"; /* Parse the type-specifier-seq. */ type_specifiers = cp_parser_type_specifier_seq (parser); /* If it's a `)', then there is no declarator. */ if (cp_lexer_next_token_is (parser->lexer, CPP_CLOSE_PAREN)) declarator = NULL_TREE; else declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_EITHER, /*ctor_dtor_or_conv_p=*/NULL, /*parenthesized_p=*/NULL); /* Restore the saved message. */ parser->type_definition_forbidden_message = saved_message; return start_handler_parms (type_specifiers, declarator); } /* Parse a throw-expression. throw-expression: throw assignment-expression [opt] Returns a THROW_EXPR representing the throw-expression. */ static tree cp_parser_throw_expression (cp_parser* parser) { tree expression; cp_token* token; cp_parser_require_keyword (parser, RID_THROW, "`throw'"); token = cp_lexer_peek_token (parser->lexer); /* Figure out whether or not there is an assignment-expression following the "throw" keyword. */ if (token->type == CPP_COMMA || token->type == CPP_SEMICOLON || token->type == CPP_CLOSE_PAREN || token->type == CPP_CLOSE_SQUARE || token->type == CPP_CLOSE_BRACE || token->type == CPP_COLON) expression = NULL_TREE; else expression = cp_parser_assignment_expression (parser); return build_throw (expression); } /* GNU Extensions */ /* Parse an (optional) asm-specification. asm-specification: asm ( string-literal ) If the asm-specification is present, returns a STRING_CST corresponding to the string-literal. Otherwise, returns NULL_TREE. */ static tree cp_parser_asm_specification_opt (cp_parser* parser) { cp_token *token; tree asm_specification; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If the next token isn't the `asm' keyword, then there's no asm-specification. */ if (!cp_parser_is_keyword (token, RID_ASM)) return NULL_TREE; /* Consume the `asm' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Look for the string-literal. */ token = cp_parser_require (parser, CPP_STRING, "string-literal"); if (token) asm_specification = token->value; else asm_specification = NULL_TREE; /* Look for the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`('"); return asm_specification; } /* Parse an asm-operand-list. asm-operand-list: asm-operand asm-operand-list , asm-operand asm-operand: string-literal ( expression ) [ string-literal ] string-literal ( expression ) Returns a TREE_LIST representing the operands. The TREE_VALUE of each node is the expression. The TREE_PURPOSE is itself a TREE_LIST whose TREE_PURPOSE is a STRING_CST for the bracketed string-literal (or NULL_TREE if not present) and whose TREE_VALUE is a STRING_CST for the string literal before the parenthesis. */ static tree cp_parser_asm_operand_list (cp_parser* parser) { tree asm_operands = NULL_TREE; while (true) { tree string_literal; tree expression; tree name; cp_token *token; if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_SQUARE)) { /* Consume the `[' token. */ cp_lexer_consume_token (parser->lexer); /* Read the operand name. */ name = cp_parser_identifier (parser); if (name != error_mark_node) name = build_string (IDENTIFIER_LENGTH (name), IDENTIFIER_POINTER (name)); /* Look for the closing `]'. */ cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'"); } else name = NULL_TREE; /* Look for the string-literal. */ token = cp_parser_require (parser, CPP_STRING, "string-literal"); string_literal = token ? token->value : error_mark_node; /* Look for the `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Parse the expression. */ expression = cp_parser_expression (parser); /* Look for the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Add this operand to the list. */ asm_operands = tree_cons (build_tree_list (name, string_literal), expression, asm_operands); /* If the next token is not a `,', there are no more operands. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) break; /* Consume the `,'. */ cp_lexer_consume_token (parser->lexer); } return nreverse (asm_operands); } /* Parse an asm-clobber-list. asm-clobber-list: string-literal asm-clobber-list , string-literal Returns a TREE_LIST, indicating the clobbers in the order that they appeared. The TREE_VALUE of each node is a STRING_CST. */ static tree cp_parser_asm_clobber_list (cp_parser* parser) { tree clobbers = NULL_TREE; while (true) { cp_token *token; tree string_literal; /* Look for the string literal. */ token = cp_parser_require (parser, CPP_STRING, "string-literal"); string_literal = token ? token->value : error_mark_node; /* Add it to the list. */ clobbers = tree_cons (NULL_TREE, string_literal, clobbers); /* If the next token is not a `,', then the list is complete. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) break; /* Consume the `,' token. */ cp_lexer_consume_token (parser->lexer); } return clobbers; } /* Parse an (optional) series of attributes. attributes: attributes attribute attribute: __attribute__ (( attribute-list [opt] )) The return value is as for cp_parser_attribute_list. */ static tree cp_parser_attributes_opt (cp_parser* parser) { tree attributes = NULL_TREE; while (true) { cp_token *token; tree attribute_list; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's not `__attribute__', then we're done. */ if (token->keyword != RID_ATTRIBUTE) break; /* Consume the `__attribute__' keyword. */ cp_lexer_consume_token (parser->lexer); /* Look for the two `(' tokens. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); if (token->type != CPP_CLOSE_PAREN) /* Parse the attribute-list. */ attribute_list = cp_parser_attribute_list (parser); else /* If the next token is a `)', then there is no attribute list. */ attribute_list = NULL; /* Look for the two `)' tokens. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Add these new attributes to the list. */ attributes = chainon (attributes, attribute_list); } return attributes; } /* Parse an attribute-list. attribute-list: attribute attribute-list , attribute attribute: identifier identifier ( identifier ) identifier ( identifier , expression-list ) identifier ( expression-list ) Returns a TREE_LIST. Each node corresponds to an attribute. THe TREE_PURPOSE of each node is the identifier indicating which attribute is in use. The TREE_VALUE represents the arguments, if any. */ static tree cp_parser_attribute_list (cp_parser* parser) { tree attribute_list = NULL_TREE; while (true) { cp_token *token; tree identifier; tree attribute; /* Look for the identifier. We also allow keywords here; for example `__attribute__ ((const))' is legal. */ token = cp_lexer_peek_token (parser->lexer); if (token->type != CPP_NAME && token->type != CPP_KEYWORD) return error_mark_node; /* Consume the token. */ token = cp_lexer_consume_token (parser->lexer); /* Save away the identifier that indicates which attribute this is. */ identifier = token->value; attribute = build_tree_list (identifier, NULL_TREE); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's an `(', then parse the attribute arguments. */ if (token->type == CPP_OPEN_PAREN) { tree arguments; arguments = (cp_parser_parenthesized_expression_list (parser, true, /*non_constant_p=*/NULL)); /* Save the identifier and arguments away. */ TREE_VALUE (attribute) = arguments; } /* Add this attribute to the list. */ TREE_CHAIN (attribute) = attribute_list; attribute_list = attribute; /* Now, look for more attributes. */ token = cp_lexer_peek_token (parser->lexer); /* If the next token isn't a `,', we're done. */ if (token->type != CPP_COMMA) break; /* Consume the comma and keep going. */ cp_lexer_consume_token (parser->lexer); } /* We built up the list in reverse order. */ return nreverse (attribute_list); } /* Parse an optional `__extension__' keyword. Returns TRUE if it is present, and FALSE otherwise. *SAVED_PEDANTIC is set to the current value of the PEDANTIC flag, regardless of whether or not the `__extension__' keyword is present. The caller is responsible for restoring the value of the PEDANTIC flag. */ static bool cp_parser_extension_opt (cp_parser* parser, int* saved_pedantic) { /* Save the old value of the PEDANTIC flag. */ *saved_pedantic = pedantic; if (cp_lexer_next_token_is_keyword (parser->lexer, RID_EXTENSION)) { /* Consume the `__extension__' token. */ cp_lexer_consume_token (parser->lexer); /* We're not being pedantic while the `__extension__' keyword is in effect. */ pedantic = 0; return true; } return false; } /* Parse a label declaration. label-declaration: __label__ label-declarator-seq ; label-declarator-seq: identifier , label-declarator-seq identifier */ static void cp_parser_label_declaration (cp_parser* parser) { /* Look for the `__label__' keyword. */ cp_parser_require_keyword (parser, RID_LABEL, "`__label__'"); while (true) { tree identifier; /* Look for an identifier. */ identifier = cp_parser_identifier (parser); /* Declare it as a lobel. */ finish_label_decl (identifier); /* If the next token is a `;', stop. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON)) break; /* Look for the `,' separating the label declarations. */ cp_parser_require (parser, CPP_COMMA, "`,'"); } /* Look for the final `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); } /* Support Functions */ /* Looks up NAME in the current scope, as given by PARSER->SCOPE. NAME should have one of the representations used for an id-expression. If NAME is the ERROR_MARK_NODE, the ERROR_MARK_NODE is returned. If PARSER->SCOPE is a dependent type, then a SCOPE_REF is returned. If NAME is a TEMPLATE_ID_EXPR, then it will be immediately returned; the name was already resolved when the TEMPLATE_ID_EXPR was formed. Abstractly, such entities should not be passed to this function, because they do not need to be looked up, but it is simpler to check for this special case here, rather than at the call-sites. In cases not explicitly covered above, this function returns a DECL, OVERLOAD, or baselink representing the result of the lookup. If there was no entity with the indicated NAME, the ERROR_MARK_NODE is returned. If IS_TYPE is TRUE, bindings that do not refer to types are ignored. If IS_TEMPLATE is TRUE, bindings that do not refer to templates are ignored. If IS_NAMESPACE is TRUE, bindings that do not refer to namespaces are ignored. If CHECK_DEPENDENCY is TRUE, names are not looked up in dependent types. */ static tree cp_parser_lookup_name (cp_parser *parser, tree name, bool is_type, bool is_template, bool is_namespace, bool check_dependency) { tree decl; tree object_type = parser->context->object_type; /* Now that we have looked up the name, the OBJECT_TYPE (if any) is no longer valid. Note that if we are parsing tentatively, and the parse fails, OBJECT_TYPE will be automatically restored. */ parser->context->object_type = NULL_TREE; if (name == error_mark_node) return error_mark_node; /* A template-id has already been resolved; there is no lookup to do. */ if (TREE_CODE (name) == TEMPLATE_ID_EXPR) return name; if (BASELINK_P (name)) { my_friendly_assert ((TREE_CODE (BASELINK_FUNCTIONS (name)) == TEMPLATE_ID_EXPR), 20020909); return name; } /* A BIT_NOT_EXPR is used to represent a destructor. By this point, it should already have been checked to make sure that the name used matches the type being destroyed. */ if (TREE_CODE (name) == BIT_NOT_EXPR) { tree type; /* Figure out to which type this destructor applies. */ if (parser->scope) type = parser->scope; else if (object_type) type = object_type; else type = current_class_type; /* If that's not a class type, there is no destructor. */ if (!type || !CLASS_TYPE_P (type)) return error_mark_node; if (!CLASSTYPE_DESTRUCTORS (type)) return error_mark_node; /* If it was a class type, return the destructor. */ return CLASSTYPE_DESTRUCTORS (type); } /* By this point, the NAME should be an ordinary identifier. If the id-expression was a qualified name, the qualifying scope is stored in PARSER->SCOPE at this point. */ my_friendly_assert (TREE_CODE (name) == IDENTIFIER_NODE, 20000619); /* Perform the lookup. */ if (parser->scope) { bool dependent_p; if (parser->scope == error_mark_node) return error_mark_node; /* If the SCOPE is dependent, the lookup must be deferred until the template is instantiated -- unless we are explicitly looking up names in uninstantiated templates. Even then, we cannot look up the name if the scope is not a class type; it might, for example, be a template type parameter. */ dependent_p = (TYPE_P (parser->scope) && !(parser->in_declarator_p && currently_open_class (parser->scope)) && dependent_type_p (parser->scope)); if ((check_dependency || !CLASS_TYPE_P (parser->scope)) && dependent_p) { if (is_type) /* The resolution to Core Issue 180 says that `struct A::B' should be considered a type-name, even if `A' is dependent. */ decl = TYPE_NAME (make_typename_type (parser->scope, name, /*complain=*/1)); else if (is_template) decl = make_unbound_class_template (parser->scope, name, /*complain=*/1); else decl = build_nt (SCOPE_REF, parser->scope, name); } else { bool pop_p = false; /* If PARSER->SCOPE is a dependent type, then it must be a class type, and we must not be checking dependencies; otherwise, we would have processed this lookup above. So that PARSER->SCOPE is not considered a dependent base by lookup_member, we must enter the scope here. */ if (dependent_p) pop_p = push_scope (parser->scope); /* If the PARSER->SCOPE is a a template specialization, it may be instantiated during name lookup. In that case, errors may be issued. Even if we rollback the current tentative parse, those errors are valid. */ decl = lookup_qualified_name (parser->scope, name, is_type, /*complain=*/true); if (pop_p) pop_scope (parser->scope); } parser->qualifying_scope = parser->scope; parser->object_scope = NULL_TREE; } else if (object_type) { tree object_decl = NULL_TREE; /* Look up the name in the scope of the OBJECT_TYPE, unless the OBJECT_TYPE is not a class. */ if (CLASS_TYPE_P (object_type)) /* If the OBJECT_TYPE is a template specialization, it may be instantiated during name lookup. In that case, errors may be issued. Even if we rollback the current tentative parse, those errors are valid. */ object_decl = lookup_member (object_type, name, /*protect=*/0, is_type); /* Look it up in the enclosing context, too. */ decl = lookup_name_real (name, is_type, /*nonclass=*/0, is_namespace, /*flags=*/0); parser->object_scope = object_type; parser->qualifying_scope = NULL_TREE; if (object_decl) decl = object_decl; } else { decl = lookup_name_real (name, is_type, /*nonclass=*/0, is_namespace, /*flags=*/0); parser->qualifying_scope = NULL_TREE; parser->object_scope = NULL_TREE; } /* If the lookup failed, let our caller know. */ if (!decl || decl == error_mark_node || (TREE_CODE (decl) == FUNCTION_DECL && DECL_ANTICIPATED (decl))) return error_mark_node; /* If it's a TREE_LIST, the result of the lookup was ambiguous. */ if (TREE_CODE (decl) == TREE_LIST) { /* The error message we have to print is too complicated for cp_parser_error, so we incorporate its actions directly. */ if (!cp_parser_simulate_error (parser)) { error ("reference to `%D' is ambiguous", name); print_candidates (decl); } return error_mark_node; } my_friendly_assert (DECL_P (decl) || TREE_CODE (decl) == OVERLOAD || TREE_CODE (decl) == SCOPE_REF || TREE_CODE (decl) == UNBOUND_CLASS_TEMPLATE || BASELINK_P (decl), 20000619); /* If we have resolved the name of a member declaration, check to see if the declaration is accessible. When the name resolves to set of overloaded functions, accessibility is checked when overload resolution is done. During an explicit instantiation, access is not checked at all, as per [temp.explicit]. */ if (DECL_P (decl)) check_accessibility_of_qualified_id (decl, object_type, parser->scope); return decl; } /* Like cp_parser_lookup_name, but for use in the typical case where CHECK_ACCESS is TRUE, IS_TYPE is FALSE, IS_TEMPLATE is FALSE, IS_NAMESPACE is FALSE, and CHECK_DEPENDENCY is TRUE. */ static tree cp_parser_lookup_name_simple (cp_parser* parser, tree name) { return cp_parser_lookup_name (parser, name, /*is_type=*/false, /*is_template=*/false, /*is_namespace=*/false, /*check_dependency=*/true); } /* If DECL is a TEMPLATE_DECL that can be treated like a TYPE_DECL in the current context, return the TYPE_DECL. If TAG_NAME_P is true, the DECL indicates the class being defined in a class-head, or declared in an elaborated-type-specifier. Otherwise, return DECL. */ static tree cp_parser_maybe_treat_template_as_class (tree decl, bool tag_name_p) { /* If the TEMPLATE_DECL is being declared as part of a class-head, the translation from TEMPLATE_DECL to TYPE_DECL occurs: struct A { template struct B; }; template struct A::B {}; Similarly, in a elaborated-type-specifier: namespace N { struct X{}; } struct A { template friend struct N::X; }; However, if the DECL refers to a class type, and we are in the scope of the class, then the name lookup automatically finds the TYPE_DECL created by build_self_reference rather than a TEMPLATE_DECL. For example, in: template struct S { S s; }; there is no need to handle such case. */ if (DECL_CLASS_TEMPLATE_P (decl) && tag_name_p) return DECL_TEMPLATE_RESULT (decl); return decl; } /* If too many, or too few, template-parameter lists apply to the declarator, issue an error message. Returns TRUE if all went well, and FALSE otherwise. */ static bool cp_parser_check_declarator_template_parameters (cp_parser* parser, tree declarator) { unsigned num_templates; /* We haven't seen any classes that involve template parameters yet. */ num_templates = 0; switch (TREE_CODE (declarator)) { case CALL_EXPR: case ARRAY_REF: case INDIRECT_REF: case ADDR_EXPR: { tree main_declarator = TREE_OPERAND (declarator, 0); return cp_parser_check_declarator_template_parameters (parser, main_declarator); } case SCOPE_REF: { tree scope; tree member; scope = TREE_OPERAND (declarator, 0); member = TREE_OPERAND (declarator, 1); /* If this is a pointer-to-member, then we are not interested in the SCOPE, because it does not qualify the thing that is being declared. */ if (TREE_CODE (member) == INDIRECT_REF) return (cp_parser_check_declarator_template_parameters (parser, member)); while (scope && CLASS_TYPE_P (scope)) { /* You're supposed to have one `template <...>' for every template class, but you don't need one for a full specialization. For example: template struct S{}; template <> struct S { void f(); }; void S::f () {} is correct; there shouldn't be a `template <>' for the definition of `S::f'. */ if (CLASSTYPE_TEMPLATE_INFO (scope) && (CLASSTYPE_TEMPLATE_INSTANTIATION (scope) || uses_template_parms (CLASSTYPE_TI_ARGS (scope))) && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (scope))) ++num_templates; scope = TYPE_CONTEXT (scope); } } /* Fall through. */ default: /* If the DECLARATOR has the form `X' then it uses one additional level of template parameters. */ if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR) ++num_templates; return cp_parser_check_template_parameters (parser, num_templates); } } /* NUM_TEMPLATES were used in the current declaration. If that is invalid, return FALSE and issue an error messages. Otherwise, return TRUE. */ static bool cp_parser_check_template_parameters (cp_parser* parser, unsigned num_templates) { /* If there are more template classes than parameter lists, we have something like: template void S::R::f (); */ if (parser->num_template_parameter_lists < num_templates) { error ("too few template-parameter-lists"); return false; } /* If there are the same number of template classes and parameter lists, that's OK. */ if (parser->num_template_parameter_lists == num_templates) return true; /* If there are more, but only one more, then we are referring to a member template. That's OK too. */ if (parser->num_template_parameter_lists == num_templates + 1) return true; /* Otherwise, there are too many template parameter lists. We have something like: template template void S::f(); */ error ("too many template-parameter-lists"); return false; } /* Parse a binary-expression of the general form: binary-expression: binary-expression The TOKEN_TREE_MAP maps types to codes. FN is used to parser the s. If the first production is used, then the value returned by FN is returned directly. Otherwise, a node with the indicated EXPR_TYPE is returned, with operands corresponding to the two sub-expressions. */ static tree cp_parser_binary_expression (cp_parser* parser, const cp_parser_token_tree_map token_tree_map, cp_parser_expression_fn fn) { tree lhs; /* Parse the first expression. */ lhs = (*fn) (parser); /* Now, look for more expressions. */ while (true) { cp_token *token; const cp_parser_token_tree_map_node *map_node; tree rhs; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If the token is `>', and that's not an operator at the moment, then we're done. */ if (token->type == CPP_GREATER && !parser->greater_than_is_operator_p) break; /* If we find one of the tokens we want, build the corresponding tree representation. */ for (map_node = token_tree_map; map_node->token_type != CPP_EOF; ++map_node) if (map_node->token_type == token->type) { /* Assume that an overloaded operator will not be used. */ bool overloaded_p = false; /* Consume the operator token. */ cp_lexer_consume_token (parser->lexer); /* Parse the right-hand side of the expression. */ rhs = (*fn) (parser); /* Build the binary tree node. */ lhs = build_x_binary_op (map_node->tree_type, lhs, rhs, &overloaded_p); /* If the binary operator required the use of an overloaded operator, then this expression cannot be an integral constant-expression. An overloaded operator can be used even if both operands are otherwise permissible in an integral constant-expression if at least one of the operands is of enumeration type. */ if (overloaded_p && (cp_parser_non_integral_constant_expression (parser, "calls to overloaded operators"))) lhs = error_mark_node; break; } /* If the token wasn't one of the ones we want, we're done. */ if (map_node->token_type == CPP_EOF) break; } return lhs; } /* Parse an optional `::' token indicating that the following name is from the global namespace. If so, PARSER->SCOPE is set to the GLOBAL_NAMESPACE. Otherwise, PARSER->SCOPE is set to NULL_TREE, unless CURRENT_SCOPE_VALID_P is TRUE, in which case it is left alone. Returns the new value of PARSER->SCOPE, if the `::' token is present, and NULL_TREE otherwise. */ static tree cp_parser_global_scope_opt (cp_parser* parser, bool current_scope_valid_p) { cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If we're looking at a `::' token then we're starting from the global namespace, not our current location. */ if (token->type == CPP_SCOPE) { /* Consume the `::' token. */ cp_lexer_consume_token (parser->lexer); /* Set the SCOPE so that we know where to start the lookup. */ parser->scope = global_namespace; parser->qualifying_scope = global_namespace; parser->object_scope = NULL_TREE; return parser->scope; } else if (!current_scope_valid_p) { parser->scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; parser->object_scope = NULL_TREE; } return NULL_TREE; } /* Returns TRUE if the upcoming token sequence is the start of a constructor declarator. If FRIEND_P is true, the declarator is preceded by the `friend' specifier. */ static bool cp_parser_constructor_declarator_p (cp_parser *parser, bool friend_p) { bool constructor_p; tree type_decl = NULL_TREE; bool nested_name_p; cp_token *next_token; /* The common case is that this is not a constructor declarator, so try to avoid doing lots of work if at all possible. It's not valid declare a constructor at function scope. */ if (at_function_scope_p ()) return false; /* And only certain tokens can begin a constructor declarator. */ next_token = cp_lexer_peek_token (parser->lexer); if (next_token->type != CPP_NAME && next_token->type != CPP_SCOPE && next_token->type != CPP_NESTED_NAME_SPECIFIER && next_token->type != CPP_TEMPLATE_ID) return false; /* Parse tentatively; we are going to roll back all of the tokens consumed here. */ cp_parser_parse_tentatively (parser); /* Assume that we are looking at a constructor declarator. */ constructor_p = true; /* Look for the optional `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* Look for the nested-name-specifier. */ nested_name_p = (cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/false, /*type_p=*/false, /*is_declaration=*/false) != NULL_TREE); /* Outside of a class-specifier, there must be a nested-name-specifier. */ if (!nested_name_p && (!at_class_scope_p () || !TYPE_BEING_DEFINED (current_class_type) || friend_p)) constructor_p = false; /* If we still think that this might be a constructor-declarator, look for a class-name. */ if (constructor_p) { /* If we have: template struct S { S(); }; template S::S (); we must recognize that the nested `S' names a class. Similarly, for: template S::S (); we must recognize that the nested `S' names a template. */ type_decl = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, /*type_p=*/false, /*check_dependency_p=*/false, /*class_head_p=*/false, /*is_declaration=*/false); /* If there was no class-name, then this is not a constructor. */ constructor_p = !cp_parser_error_occurred (parser); } /* If we're still considering a constructor, we have to see a `(', to begin the parameter-declaration-clause, followed by either a `)', an `...', or a decl-specifier. We need to check for a type-specifier to avoid being fooled into thinking that: S::S (f) (int); is a constructor. (It is actually a function named `f' that takes one parameter (of type `int') and returns a value of type `S::S'. */ if (constructor_p && cp_parser_require (parser, CPP_OPEN_PAREN, "`('")) { if (cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN) && cp_lexer_next_token_is_not (parser->lexer, CPP_ELLIPSIS) /* A parameter declaration begins with a decl-specifier, which is either the "attribute" keyword, a storage class specifier, or (usually) a type-specifier. */ && !cp_lexer_next_token_is_keyword (parser->lexer, RID_ATTRIBUTE) && !cp_parser_storage_class_specifier_opt (parser)) { tree type; bool pop_p = false; unsigned saved_num_template_parameter_lists; /* Names appearing in the type-specifier should be looked up in the scope of the class. */ if (current_class_type) type = NULL_TREE; else { type = TREE_TYPE (type_decl); if (TREE_CODE (type) == TYPENAME_TYPE) { type = resolve_typename_type (type, /*only_current_p=*/false); if (type == error_mark_node) { cp_parser_abort_tentative_parse (parser); return false; } } pop_p = push_scope (type); } /* Inside the constructor parameter list, surrounding template-parameter-lists do not apply. */ saved_num_template_parameter_lists = parser->num_template_parameter_lists; parser->num_template_parameter_lists = 0; /* Look for the type-specifier. */ cp_parser_type_specifier (parser, CP_PARSER_FLAGS_NONE, /*is_friend=*/false, /*is_declarator=*/true, /*declares_class_or_enum=*/NULL, /*is_cv_qualifier=*/NULL); parser->num_template_parameter_lists = saved_num_template_parameter_lists; /* Leave the scope of the class. */ if (pop_p) pop_scope (type); constructor_p = !cp_parser_error_occurred (parser); } } else constructor_p = false; /* We did not really want to consume any tokens. */ cp_parser_abort_tentative_parse (parser); return constructor_p; } /* Parse the definition of the function given by the DECL_SPECIFIERS, ATTRIBUTES, and DECLARATOR. The access checks have been deferred; they must be performed once we are in the scope of the function. Returns the function defined. */ static tree cp_parser_function_definition_from_specifiers_and_declarator (cp_parser* parser, tree decl_specifiers, tree attributes, tree declarator) { tree fn; bool success_p; /* Begin the function-definition. */ success_p = begin_function_definition (decl_specifiers, attributes, declarator); /* If there were names looked up in the decl-specifier-seq that we did not check, check them now. We must wait until we are in the scope of the function to perform the checks, since the function might be a friend. */ perform_deferred_access_checks (); if (!success_p) { /* If begin_function_definition didn't like the definition, skip the entire function. */ error ("invalid function declaration"); cp_parser_skip_to_end_of_block_or_statement (parser); fn = error_mark_node; } else fn = cp_parser_function_definition_after_declarator (parser, /*inline_p=*/false); return fn; } /* Parse the part of a function-definition that follows the declarator. INLINE_P is TRUE iff this function is an inline function defined with a class-specifier. Returns the function defined. */ static tree cp_parser_function_definition_after_declarator (cp_parser* parser, bool inline_p) { tree fn; bool ctor_initializer_p = false; bool saved_in_unbraced_linkage_specification_p; unsigned saved_num_template_parameter_lists; /* If the next token is `return', then the code may be trying to make use of the "named return value" extension that G++ used to support. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_RETURN)) { /* Consume the `return' keyword. */ cp_lexer_consume_token (parser->lexer); /* Look for the identifier that indicates what value is to be returned. */ cp_parser_identifier (parser); /* Issue an error message. */ error ("named return values are no longer supported"); /* Skip tokens until we reach the start of the function body. */ while (cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_BRACE) && cp_lexer_next_token_is_not (parser->lexer, CPP_EOF)) cp_lexer_consume_token (parser->lexer); } /* The `extern' in `extern "C" void f () { ... }' does not apply to anything declared inside `f'. */ saved_in_unbraced_linkage_specification_p = parser->in_unbraced_linkage_specification_p; parser->in_unbraced_linkage_specification_p = false; /* Inside the function, surrounding template-parameter-lists do not apply. */ saved_num_template_parameter_lists = parser->num_template_parameter_lists; parser->num_template_parameter_lists = 0; /* If the next token is `try', then we are looking at a function-try-block. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_TRY)) ctor_initializer_p = cp_parser_function_try_block (parser); /* A function-try-block includes the function-body, so we only do this next part if we're not processing a function-try-block. */ else ctor_initializer_p = cp_parser_ctor_initializer_opt_and_function_body (parser); /* Finish the function. */ fn = finish_function ((ctor_initializer_p ? 1 : 0) | (inline_p ? 2 : 0)); /* Generate code for it, if necessary. */ expand_or_defer_fn (fn); /* Restore the saved values. */ parser->in_unbraced_linkage_specification_p = saved_in_unbraced_linkage_specification_p; parser->num_template_parameter_lists = saved_num_template_parameter_lists; return fn; } /* Parse a template-declaration, assuming that the `export' (and `extern') keywords, if present, has already been scanned. MEMBER_P is as for cp_parser_template_declaration. */ static void cp_parser_template_declaration_after_export (cp_parser* parser, bool member_p) { tree decl = NULL_TREE; tree parameter_list; bool friend_p = false; /* Look for the `template' keyword. */ if (!cp_parser_require_keyword (parser, RID_TEMPLATE, "`template'")) return; /* And the `<'. */ if (!cp_parser_require (parser, CPP_LESS, "`<'")) return; /* If the next token is `>', then we have an invalid specialization. Rather than complain about an invalid template parameter, issue an error message here. */ if (cp_lexer_next_token_is (parser->lexer, CPP_GREATER)) { cp_parser_error (parser, "invalid explicit specialization"); begin_specialization (); parameter_list = NULL_TREE; } else { /* Parse the template parameters. */ begin_template_parm_list (); parameter_list = cp_parser_template_parameter_list (parser); parameter_list = end_template_parm_list (parameter_list); } /* Look for the `>'. */ cp_parser_skip_until_found (parser, CPP_GREATER, "`>'"); /* We just processed one more parameter list. */ ++parser->num_template_parameter_lists; /* If the next token is `template', there are more template parameters. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_TEMPLATE)) cp_parser_template_declaration_after_export (parser, member_p); else { decl = cp_parser_single_declaration (parser, member_p, &friend_p); /* If this is a member template declaration, let the front end know. */ if (member_p && !friend_p && decl) { if (TREE_CODE (decl) == TYPE_DECL) cp_parser_check_access_in_redeclaration (decl); decl = finish_member_template_decl (decl); } else if (friend_p && decl && TREE_CODE (decl) == TYPE_DECL) make_friend_class (current_class_type, TREE_TYPE (decl), /*complain=*/true); } /* We are done with the current parameter list. */ --parser->num_template_parameter_lists; /* Finish up. */ finish_template_decl (parameter_list); /* Register member declarations. */ if (member_p && !friend_p && decl && !DECL_CLASS_TEMPLATE_P (decl)) finish_member_declaration (decl); /* If DECL is a function template, we must return to parse it later. (Even though there is no definition, there might be default arguments that need handling.) */ if (member_p && decl && (TREE_CODE (decl) == FUNCTION_DECL || DECL_FUNCTION_TEMPLATE_P (decl))) TREE_VALUE (parser->unparsed_functions_queues) = tree_cons (NULL_TREE, decl, TREE_VALUE (parser->unparsed_functions_queues)); } /* Parse a `decl-specifier-seq [opt] init-declarator [opt] ;' or `function-definition' sequence. MEMBER_P is true, this declaration appears in a class scope. Returns the DECL for the declared entity. If FRIEND_P is non-NULL, *FRIEND_P is set to TRUE iff the declaration is a friend. */ static tree cp_parser_single_declaration (cp_parser* parser, bool member_p, bool* friend_p) { int declares_class_or_enum; tree decl = NULL_TREE; tree decl_specifiers; tree attributes; bool function_definition_p = false; /* Defer access checks until we know what is being declared. */ push_deferring_access_checks (dk_deferred); /* Try the `decl-specifier-seq [opt] init-declarator [opt]' alternative. */ decl_specifiers = cp_parser_decl_specifier_seq (parser, CP_PARSER_FLAGS_OPTIONAL, &attributes, &declares_class_or_enum); if (friend_p) *friend_p = cp_parser_friend_p (decl_specifiers); /* Gather up the access checks that occurred the decl-specifier-seq. */ stop_deferring_access_checks (); /* Check for the declaration of a template class. */ if (declares_class_or_enum) { if (cp_parser_declares_only_class_p (parser)) { decl = shadow_tag (decl_specifiers); if (decl) decl = TYPE_NAME (decl); else decl = error_mark_node; } } else decl = NULL_TREE; /* If it's not a template class, try for a template function. If the next token is a `;', then this declaration does not declare anything. But, if there were errors in the decl-specifiers, then the error might well have come from an attempted class-specifier. In that case, there's no need to warn about a missing declarator. */ if (!decl && (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON) || !value_member (error_mark_node, decl_specifiers))) decl = cp_parser_init_declarator (parser, decl_specifiers, attributes, /*function_definition_allowed_p=*/true, member_p, declares_class_or_enum, &function_definition_p); pop_deferring_access_checks (); /* Clear any current qualification; whatever comes next is the start of something new. */ parser->scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; parser->object_scope = NULL_TREE; /* Look for a trailing `;' after the declaration. */ if (!function_definition_p && !cp_parser_require (parser, CPP_SEMICOLON, "`;'")) cp_parser_skip_to_end_of_block_or_statement (parser); return decl; } /* Parse a cast-expression that is not the operand of a unary "&". */ static tree cp_parser_simple_cast_expression (cp_parser *parser) { return cp_parser_cast_expression (parser, /*address_p=*/false); } /* Parse a functional cast to TYPE. Returns an expression representing the cast. */ static tree cp_parser_functional_cast (cp_parser* parser, tree type) { tree expression_list; tree cast; expression_list = cp_parser_parenthesized_expression_list (parser, false, /*non_constant_p=*/NULL); cast = build_functional_cast (type, expression_list); /* [expr.const]/1: In an integral constant expression "only type conversions to integral or enumeration type can be used". */ if (cast != error_mark_node && !type_dependent_expression_p (type) && !INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (type))) { if (cp_parser_non_integral_constant_expression (parser, "a call to a constructor")) return error_mark_node; } return cast; } /* Save the tokens that make up the body of a member function defined in a class-specifier. The DECL_SPECIFIERS and DECLARATOR have already been parsed. The ATTRIBUTES are any GNU "__attribute__" specifiers applied to the declaration. Returns the FUNCTION_DECL for the member function. */ static tree cp_parser_save_member_function_body (cp_parser* parser, tree decl_specifiers, tree declarator, tree attributes) { cp_token_cache *cache; tree fn; /* Create the function-declaration. */ fn = start_method (decl_specifiers, declarator, attributes); /* If something went badly wrong, bail out now. */ if (fn == error_mark_node) { /* If there's a function-body, skip it. */ if (cp_parser_token_starts_function_definition_p (cp_lexer_peek_token (parser->lexer))) cp_parser_skip_to_end_of_block_or_statement (parser); return error_mark_node; } /* Remember it, if there default args to post process. */ cp_parser_save_default_args (parser, fn); /* Create a token cache. */ cache = cp_token_cache_new (); /* Save away the tokens that make up the body of the function. */ cp_parser_cache_group (parser, cache, CPP_CLOSE_BRACE, /*depth=*/0); /* Handle function try blocks. */ while (cp_lexer_next_token_is_keyword (parser->lexer, RID_CATCH)) cp_parser_cache_group (parser, cache, CPP_CLOSE_BRACE, /*depth=*/0); /* Save away the inline definition; we will process it when the class is complete. */ DECL_PENDING_INLINE_INFO (fn) = cache; DECL_PENDING_INLINE_P (fn) = 1; /* We need to know that this was defined in the class, so that friend templates are handled correctly. */ DECL_INITIALIZED_IN_CLASS_P (fn) = 1; /* We're done with the inline definition. */ finish_method (fn); /* Add FN to the queue of functions to be parsed later. */ TREE_VALUE (parser->unparsed_functions_queues) = tree_cons (NULL_TREE, fn, TREE_VALUE (parser->unparsed_functions_queues)); return fn; } /* Parse a template-argument-list, as well as the trailing ">" (but not the opening ">"). See cp_parser_template_argument_list for the return value. */ static tree cp_parser_enclosed_template_argument_list (cp_parser* parser) { tree arguments; tree saved_scope; tree saved_qualifying_scope; tree saved_object_scope; bool saved_greater_than_is_operator_p; /* [temp.names] When parsing a template-id, the first non-nested `>' is taken as the end of the template-argument-list rather than a greater-than operator. */ saved_greater_than_is_operator_p = parser->greater_than_is_operator_p; parser->greater_than_is_operator_p = false; /* Parsing the argument list may modify SCOPE, so we save it here. */ saved_scope = parser->scope; saved_qualifying_scope = parser->qualifying_scope; saved_object_scope = parser->object_scope; /* Parse the template-argument-list itself. */ if (cp_lexer_next_token_is (parser->lexer, CPP_GREATER)) arguments = NULL_TREE; else arguments = cp_parser_template_argument_list (parser); /* Look for the `>' that ends the template-argument-list. If we find a '>>' instead, it's probably just a typo. */ if (cp_lexer_next_token_is (parser->lexer, CPP_RSHIFT)) { if (!saved_greater_than_is_operator_p) { /* If we're in a nested template argument list, the '>>' has to be a typo for '> >'. We emit the error message, but we continue parsing and we push a '>' as next token, so that the argument list will be parsed correctly.. */ cp_token* token; error ("`>>' should be `> >' within a nested template argument list"); token = cp_lexer_peek_token (parser->lexer); token->type = CPP_GREATER; } else { /* If this is not a nested template argument list, the '>>' is a typo for '>'. Emit an error message and continue. */ error ("spurious `>>', use `>' to terminate a template argument list"); cp_lexer_consume_token (parser->lexer); } } else if (!cp_parser_require (parser, CPP_GREATER, "`>'")) error ("missing `>' to terminate the template argument list"); /* The `>' token might be a greater-than operator again now. */ parser->greater_than_is_operator_p = saved_greater_than_is_operator_p; /* Restore the SAVED_SCOPE. */ parser->scope = saved_scope; parser->qualifying_scope = saved_qualifying_scope; parser->object_scope = saved_object_scope; return arguments; } /* MEMBER_FUNCTION is a member function, or a friend. If default arguments, or the body of the function have not yet been parsed, parse them now. */ static void cp_parser_late_parsing_for_member (cp_parser* parser, tree member_function) { cp_lexer *saved_lexer; /* If this member is a template, get the underlying FUNCTION_DECL. */ if (DECL_FUNCTION_TEMPLATE_P (member_function)) member_function = DECL_TEMPLATE_RESULT (member_function); /* There should not be any class definitions in progress at this point; the bodies of members are only parsed outside of all class definitions. */ my_friendly_assert (parser->num_classes_being_defined == 0, 20010816); /* While we're parsing the member functions we might encounter more classes. We want to handle them right away, but we don't want them getting mixed up with functions that are currently in the queue. */ parser->unparsed_functions_queues = tree_cons (NULL_TREE, NULL_TREE, parser->unparsed_functions_queues); /* Make sure that any template parameters are in scope. */ maybe_begin_member_template_processing (member_function); /* If the body of the function has not yet been parsed, parse it now. */ if (DECL_PENDING_INLINE_P (member_function)) { tree function_scope; cp_token_cache *tokens; /* The function is no longer pending; we are processing it. */ tokens = DECL_PENDING_INLINE_INFO (member_function); DECL_PENDING_INLINE_INFO (member_function) = NULL; DECL_PENDING_INLINE_P (member_function) = 0; /* If this was an inline function in a local class, enter the scope of the containing function. */ function_scope = decl_function_context (member_function); if (function_scope) push_function_context_to (function_scope); /* Save away the current lexer. */ saved_lexer = parser->lexer; /* Make a new lexer to feed us the tokens saved for this function. */ parser->lexer = cp_lexer_new_from_tokens (tokens); parser->lexer->next = saved_lexer; /* Set the current source position to be the location of the first token in the saved inline body. */ cp_lexer_peek_token (parser->lexer); /* Let the front end know that we going to be defining this function. */ start_function (NULL_TREE, member_function, NULL_TREE, SF_PRE_PARSED | SF_INCLASS_INLINE); /* Now, parse the body of the function. */ cp_parser_function_definition_after_declarator (parser, /*inline_p=*/true); /* Leave the scope of the containing function. */ if (function_scope) pop_function_context_from (function_scope); /* Restore the lexer. */ parser->lexer = saved_lexer; } /* Remove any template parameters from the symbol table. */ maybe_end_member_template_processing (); /* Restore the queue. */ parser->unparsed_functions_queues = TREE_CHAIN (parser->unparsed_functions_queues); } /* If DECL contains any default args, remember it on the unparsed functions queue. */ static void cp_parser_save_default_args (cp_parser* parser, tree decl) { tree probe; for (probe = TYPE_ARG_TYPES (TREE_TYPE (decl)); probe; probe = TREE_CHAIN (probe)) if (TREE_PURPOSE (probe)) { TREE_PURPOSE (parser->unparsed_functions_queues) = tree_cons (NULL_TREE, decl, TREE_PURPOSE (parser->unparsed_functions_queues)); break; } return; } /* FN is a FUNCTION_DECL which may contains a parameter with an unparsed DEFAULT_ARG. Parse the default args now. */ static void cp_parser_late_parsing_default_args (cp_parser *parser, tree fn) { cp_lexer *saved_lexer; cp_token_cache *tokens; bool saved_local_variables_forbidden_p; tree parameters; /* While we're parsing the default args, we might (due to the statement expression extension) encounter more classes. We want to handle them right away, but we don't want them getting mixed up with default args that are currently in the queue. */ parser->unparsed_functions_queues = tree_cons (NULL_TREE, NULL_TREE, parser->unparsed_functions_queues); for (parameters = TYPE_ARG_TYPES (TREE_TYPE (fn)); parameters; parameters = TREE_CHAIN (parameters)) { if (!TREE_PURPOSE (parameters) || TREE_CODE (TREE_PURPOSE (parameters)) != DEFAULT_ARG) continue; /* Save away the current lexer. */ saved_lexer = parser->lexer; /* Create a new one, using the tokens we have saved. */ tokens = DEFARG_TOKENS (TREE_PURPOSE (parameters)); parser->lexer = cp_lexer_new_from_tokens (tokens); /* Set the current source position to be the location of the first token in the default argument. */ cp_lexer_peek_token (parser->lexer); /* Local variable names (and the `this' keyword) may not appear in a default argument. */ saved_local_variables_forbidden_p = parser->local_variables_forbidden_p; parser->local_variables_forbidden_p = true; /* Parse the assignment-expression. */ if (DECL_CLASS_SCOPE_P (fn)) push_nested_class (DECL_CONTEXT (fn)); TREE_PURPOSE (parameters) = cp_parser_assignment_expression (parser); if (DECL_CLASS_SCOPE_P (fn)) pop_nested_class (); /* If the token stream has not been completely used up, then there was extra junk after the end of the default argument. */ if (!cp_lexer_next_token_is (parser->lexer, CPP_EOF)) cp_parser_error (parser, "expected `,'"); /* Restore saved state. */ parser->lexer = saved_lexer; parser->local_variables_forbidden_p = saved_local_variables_forbidden_p; } /* Restore the queue. */ parser->unparsed_functions_queues = TREE_CHAIN (parser->unparsed_functions_queues); } /* Parse the operand of `sizeof' (or a similar operator). Returns either a TYPE or an expression, depending on the form of the input. The KEYWORD indicates which kind of expression we have encountered. */ static tree cp_parser_sizeof_operand (cp_parser* parser, enum rid keyword) { static const char *format; tree expr = NULL_TREE; const char *saved_message; bool saved_integral_constant_expression_p; /* Initialize FORMAT the first time we get here. */ if (!format) format = "types may not be defined in `%s' expressions"; /* Types cannot be defined in a `sizeof' expression. Save away the old message. */ saved_message = parser->type_definition_forbidden_message; /* And create the new one. */ parser->type_definition_forbidden_message = xmalloc (strlen (format) + strlen (IDENTIFIER_POINTER (ridpointers[keyword])) + 1 /* `\0' */); sprintf ((char *) parser->type_definition_forbidden_message, format, IDENTIFIER_POINTER (ridpointers[keyword])); /* The restrictions on constant-expressions do not apply inside sizeof expressions. */ saved_integral_constant_expression_p = parser->integral_constant_expression_p; parser->integral_constant_expression_p = false; /* Do not actually evaluate the expression. */ ++skip_evaluation; /* If it's a `(', then we might be looking at the type-id construction. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN)) { tree type; bool saved_in_type_id_in_expr_p; /* We can't be sure yet whether we're looking at a type-id or an expression. */ cp_parser_parse_tentatively (parser); /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* Parse the type-id. */ saved_in_type_id_in_expr_p = parser->in_type_id_in_expr_p; parser->in_type_id_in_expr_p = true; type = cp_parser_type_id (parser); parser->in_type_id_in_expr_p = saved_in_type_id_in_expr_p; /* Now, look for the trailing `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* If all went well, then we're done. */ if (cp_parser_parse_definitely (parser)) { /* Build a list of decl-specifiers; right now, we have only a single type-specifier. */ type = build_tree_list (NULL_TREE, type); /* Call grokdeclarator to figure out what type this is. */ expr = grokdeclarator (NULL_TREE, type, TYPENAME, /*initialized=*/0, /*attrlist=*/NULL); } } /* If the type-id production did not work out, then we must be looking at the unary-expression production. */ if (!expr) expr = cp_parser_unary_expression (parser, /*address_p=*/false); /* Go back to evaluating expressions. */ --skip_evaluation; /* Free the message we created. */ free ((char *) parser->type_definition_forbidden_message); /* And restore the old one. */ parser->type_definition_forbidden_message = saved_message; parser->integral_constant_expression_p = saved_integral_constant_expression_p; return expr; } /* If the current declaration has no declarator, return true. */ static bool cp_parser_declares_only_class_p (cp_parser *parser) { /* If the next token is a `;' or a `,' then there is no declarator. */ return (cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON) || cp_lexer_next_token_is (parser->lexer, CPP_COMMA)); } /* DECL_SPECIFIERS is the representation of a decl-specifier-seq. Returns TRUE iff `friend' appears among the DECL_SPECIFIERS. */ static bool cp_parser_friend_p (tree decl_specifiers) { while (decl_specifiers) { /* See if this decl-specifier is `friend'. */ if (TREE_CODE (TREE_VALUE (decl_specifiers)) == IDENTIFIER_NODE && C_RID_CODE (TREE_VALUE (decl_specifiers)) == RID_FRIEND) return true; /* Go on to the next decl-specifier. */ decl_specifiers = TREE_CHAIN (decl_specifiers); } return false; } /* If the next token is of the indicated TYPE, consume it. Otherwise, issue an error message indicating that TOKEN_DESC was expected. Returns the token consumed, if the token had the appropriate type. Otherwise, returns NULL. */ static cp_token * cp_parser_require (cp_parser* parser, enum cpp_ttype type, const char* token_desc) { if (cp_lexer_next_token_is (parser->lexer, type)) return cp_lexer_consume_token (parser->lexer); else { /* Output the MESSAGE -- unless we're parsing tentatively. */ if (!cp_parser_simulate_error (parser)) { char *message = concat ("expected ", token_desc, NULL); cp_parser_error (parser, message); free (message); } return NULL; } } /* Like cp_parser_require, except that tokens will be skipped until the desired token is found. An error message is still produced if the next token is not as expected. */ static void cp_parser_skip_until_found (cp_parser* parser, enum cpp_ttype type, const char* token_desc) { cp_token *token; unsigned nesting_depth = 0; if (cp_parser_require (parser, type, token_desc)) return; /* Skip tokens until the desired token is found. */ while (true) { /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If we've reached the token we want, consume it and stop. */ if (token->type == type && !nesting_depth) { cp_lexer_consume_token (parser->lexer); return; } /* If we've run out of tokens, stop. */ if (token->type == CPP_EOF) return; if (token->type == CPP_OPEN_BRACE || token->type == CPP_OPEN_PAREN || token->type == CPP_OPEN_SQUARE) ++nesting_depth; else if (token->type == CPP_CLOSE_BRACE || token->type == CPP_CLOSE_PAREN || token->type == CPP_CLOSE_SQUARE) { if (nesting_depth-- == 0) return; } /* Consume this token. */ cp_lexer_consume_token (parser->lexer); } } /* If the next token is the indicated keyword, consume it. Otherwise, issue an error message indicating that TOKEN_DESC was expected. Returns the token consumed, if the token had the appropriate type. Otherwise, returns NULL. */ static cp_token * cp_parser_require_keyword (cp_parser* parser, enum rid keyword, const char* token_desc) { cp_token *token = cp_parser_require (parser, CPP_KEYWORD, token_desc); if (token && token->keyword != keyword) { dyn_string_t error_msg; /* Format the error message. */ error_msg = dyn_string_new (0); dyn_string_append_cstr (error_msg, "expected "); dyn_string_append_cstr (error_msg, token_desc); cp_parser_error (parser, error_msg->s); dyn_string_delete (error_msg); return NULL; } return token; } /* Returns TRUE iff TOKEN is a token that can begin the body of a function-definition. */ static bool cp_parser_token_starts_function_definition_p (cp_token* token) { return (/* An ordinary function-body begins with an `{'. */ token->type == CPP_OPEN_BRACE /* A ctor-initializer begins with a `:'. */ || token->type == CPP_COLON /* A function-try-block begins with `try'. */ || token->keyword == RID_TRY /* The named return value extension begins with `return'. */ || token->keyword == RID_RETURN); } /* Returns TRUE iff the next token is the ":" or "{" beginning a class definition. */ static bool cp_parser_next_token_starts_class_definition_p (cp_parser *parser) { cp_token *token; token = cp_lexer_peek_token (parser->lexer); return (token->type == CPP_OPEN_BRACE || token->type == CPP_COLON); } /* Returns TRUE iff the next token is the "," or ">" ending a template-argument. ">>" is also accepted (after the full argument was parsed) because it's probably a typo for "> >", and there is a specific diagnostic for this. */ static bool cp_parser_next_token_ends_template_argument_p (cp_parser *parser) { cp_token *token; token = cp_lexer_peek_token (parser->lexer); return (token->type == CPP_COMMA || token->type == CPP_GREATER || token->type == CPP_RSHIFT); } /* Returns TRUE iff the n-th token is a ">", or the n-th is a "[" and the (n+1)-th is a ":" (which is a possible digraph typo for "< ::"). */ static bool cp_parser_nth_token_starts_template_argument_list_p (cp_parser * parser, size_t n) { cp_token *token; token = cp_lexer_peek_nth_token (parser->lexer, n); if (token->type == CPP_LESS) return true; /* Check for the sequence `<::' in the original code. It would be lexed as `[:', where `[' is a digraph, and there is no whitespace before `:'. */ if (token->type == CPP_OPEN_SQUARE && token->flags & DIGRAPH) { cp_token *token2; token2 = cp_lexer_peek_nth_token (parser->lexer, n+1); if (token2->type == CPP_COLON && !(token2->flags & PREV_WHITE)) return true; } return false; } /* Returns the kind of tag indicated by TOKEN, if it is a class-key, or none_type otherwise. */ static enum tag_types cp_parser_token_is_class_key (cp_token* token) { switch (token->keyword) { case RID_CLASS: return class_type; case RID_STRUCT: return record_type; case RID_UNION: return union_type; default: return none_type; } } /* Issue an error message if the CLASS_KEY does not match the TYPE. */ static void cp_parser_check_class_key (enum tag_types class_key, tree type) { if ((TREE_CODE (type) == UNION_TYPE) != (class_key == union_type)) pedwarn ("`%s' tag used in naming `%#T'", class_key == union_type ? "union" : class_key == record_type ? "struct" : "class", type); } /* Issue an error message if DECL is redeclared with different access than its original declaration [class.access.spec/3]. This applies to nested classes and nested class templates. [class.mem/1]. */ static void cp_parser_check_access_in_redeclaration (tree decl) { if (!CLASS_TYPE_P (TREE_TYPE (decl))) return; if ((TREE_PRIVATE (decl) != (current_access_specifier == access_private_node)) || (TREE_PROTECTED (decl) != (current_access_specifier == access_protected_node))) error ("%D redeclared with different access", decl); } /* Look for the `template' keyword, as a syntactic disambiguator. Return TRUE iff it is present, in which case it will be consumed. */ static bool cp_parser_optional_template_keyword (cp_parser *parser) { if (cp_lexer_next_token_is_keyword (parser->lexer, RID_TEMPLATE)) { /* The `template' keyword can only be used within templates; outside templates the parser can always figure out what is a template and what is not. */ if (!processing_template_decl) { error ("`template' (as a disambiguator) is only allowed " "within templates"); /* If this part of the token stream is rescanned, the same error message would be generated. So, we purge the token from the stream. */ cp_lexer_purge_token (parser->lexer); return false; } else { /* Consume the `template' keyword. */ cp_lexer_consume_token (parser->lexer); return true; } } return false; } /* The next token is a CPP_NESTED_NAME_SPECIFIER. Consume the token, set PARSER->SCOPE, and perform other related actions. */ static void cp_parser_pre_parsed_nested_name_specifier (cp_parser *parser) { tree value; tree check; /* Get the stored value. */ value = cp_lexer_consume_token (parser->lexer)->value; /* Perform any access checks that were deferred. */ for (check = TREE_PURPOSE (value); check; check = TREE_CHAIN (check)) perform_or_defer_access_check (TREE_PURPOSE (check), TREE_VALUE (check)); /* Set the scope from the stored value. */ parser->scope = TREE_VALUE (value); parser->qualifying_scope = TREE_TYPE (value); parser->object_scope = NULL_TREE; } /* Add tokens to CACHE until an non-nested END token appears. */ static void cp_parser_cache_group (cp_parser *parser, cp_token_cache *cache, enum cpp_ttype end, unsigned depth) { while (true) { cp_token *token; /* Abort a parenthesized expression if we encounter a brace. */ if ((end == CPP_CLOSE_PAREN || depth == 0) && cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON)) return; /* If we've reached the end of the file, stop. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EOF)) return; /* Consume the next token. */ token = cp_lexer_consume_token (parser->lexer); /* Add this token to the tokens we are saving. */ cp_token_cache_push_token (cache, token); /* See if it starts a new group. */ if (token->type == CPP_OPEN_BRACE) { cp_parser_cache_group (parser, cache, CPP_CLOSE_BRACE, depth + 1); if (depth == 0) return; } else if (token->type == CPP_OPEN_PAREN) cp_parser_cache_group (parser, cache, CPP_CLOSE_PAREN, depth + 1); else if (token->type == end) return; } } /* Begin parsing tentatively. We always save tokens while parsing tentatively so that if the tentative parsing fails we can restore the tokens. */ static void cp_parser_parse_tentatively (cp_parser* parser) { /* Enter a new parsing context. */ parser->context = cp_parser_context_new (parser->context); /* Begin saving tokens. */ cp_lexer_save_tokens (parser->lexer); /* In order to avoid repetitive access control error messages, access checks are queued up until we are no longer parsing tentatively. */ push_deferring_access_checks (dk_deferred); } /* Commit to the currently active tentative parse. */ static void cp_parser_commit_to_tentative_parse (cp_parser* parser) { cp_parser_context *context; cp_lexer *lexer; /* Mark all of the levels as committed. */ lexer = parser->lexer; for (context = parser->context; context->next; context = context->next) { if (context->status == CP_PARSER_STATUS_KIND_COMMITTED) break; context->status = CP_PARSER_STATUS_KIND_COMMITTED; while (!cp_lexer_saving_tokens (lexer)) lexer = lexer->next; cp_lexer_commit_tokens (lexer); } } /* Abort the currently active tentative parse. All consumed tokens will be rolled back, and no diagnostics will be issued. */ static void cp_parser_abort_tentative_parse (cp_parser* parser) { cp_parser_simulate_error (parser); /* Now, pretend that we want to see if the construct was successfully parsed. */ cp_parser_parse_definitely (parser); } /* Stop parsing tentatively. If a parse error has occurred, restore the token stream. Otherwise, commit to the tokens we have consumed. Returns true if no error occurred; false otherwise. */ static bool cp_parser_parse_definitely (cp_parser* parser) { bool error_occurred; cp_parser_context *context; /* Remember whether or not an error occurred, since we are about to destroy that information. */ error_occurred = cp_parser_error_occurred (parser); /* Remove the topmost context from the stack. */ context = parser->context; parser->context = context->next; /* If no parse errors occurred, commit to the tentative parse. */ if (!error_occurred) { /* Commit to the tokens read tentatively, unless that was already done. */ if (context->status != CP_PARSER_STATUS_KIND_COMMITTED) cp_lexer_commit_tokens (parser->lexer); pop_to_parent_deferring_access_checks (); } /* Otherwise, if errors occurred, roll back our state so that things are just as they were before we began the tentative parse. */ else { cp_lexer_rollback_tokens (parser->lexer); pop_deferring_access_checks (); } /* Add the context to the front of the free list. */ context->next = cp_parser_context_free_list; cp_parser_context_free_list = context; return !error_occurred; } /* Returns true if we are parsing tentatively -- but have decided that we will stick with this tentative parse, even if errors occur. */ static bool cp_parser_committed_to_tentative_parse (cp_parser* parser) { return (cp_parser_parsing_tentatively (parser) && parser->context->status == CP_PARSER_STATUS_KIND_COMMITTED); } /* Returns nonzero iff an error has occurred during the most recent tentative parse. */ static bool cp_parser_error_occurred (cp_parser* parser) { return (cp_parser_parsing_tentatively (parser) && parser->context->status == CP_PARSER_STATUS_KIND_ERROR); } /* Returns nonzero if GNU extensions are allowed. */ static bool cp_parser_allow_gnu_extensions_p (cp_parser* parser) { return parser->allow_gnu_extensions_p; } /* The parser. */ static GTY (()) cp_parser *the_parser; /* External interface. */ /* Parse one entire translation unit. */ void c_parse_file (void) { bool error_occurred; the_parser = cp_parser_new (); push_deferring_access_checks (flag_access_control ? dk_no_deferred : dk_no_check); error_occurred = cp_parser_translation_unit (the_parser); the_parser = NULL; } /* This variable must be provided by every front end. */ int yydebug; #include "gt-cp-parser.h"