/* Process declarations and variables for C++ compiler. Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. Hacked by Michael Tiemann (tiemann@cygnus.com) 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. */ /* Process declarations and symbol lookup for C++ front end. Also constructs types; the standard scalar types at initialization, and structure, union, array and enum types when they are declared. */ /* ??? not all decl nodes are given the most useful possible line numbers. For example, the CONST_DECLs for enum values. */ #include "config.h" #include "system.h" #include "coretypes.h" #include "tm.h" #include "tree.h" #include "rtl.h" #include "expr.h" #include "flags.h" #include "cp-tree.h" #include "decl.h" #include "output.h" #include "except.h" #include "toplev.h" #include "timevar.h" #include "cpplib.h" #include "target.h" #include "c-common.h" #include "tree-mudflap.h" #include "cgraph.h" #include "tree-inline.h" #include "c-pragma.h" extern cpp_reader *parse_in; /* This structure contains information about the initializations and/or destructions required for a particular priority level. */ typedef struct priority_info_s { /* Nonzero if there have been any initializations at this priority throughout the translation unit. */ int initializations_p; /* Nonzero if there have been any destructions at this priority throughout the translation unit. */ int destructions_p; } *priority_info; static void mark_vtable_entries (tree); static bool maybe_emit_vtables (tree); static bool acceptable_java_type (tree); static tree start_objects (int, int); static void finish_objects (int, int, tree); static tree start_static_storage_duration_function (unsigned); static void finish_static_storage_duration_function (tree); static priority_info get_priority_info (int); static void do_static_initialization (tree, tree); static void do_static_destruction (tree); static tree start_static_initialization_or_destruction (tree, int); static void finish_static_initialization_or_destruction (tree); static void generate_ctor_or_dtor_function (bool, int, location_t *); static int generate_ctor_and_dtor_functions_for_priority (splay_tree_node, void *); static tree prune_vars_needing_no_initialization (tree *); static void write_out_vars (tree); static void import_export_class (tree); static tree get_guard_bits (tree); /* A list of static class variables. This is needed, because a static class variable can be declared inside the class without an initializer, and then initialized, statically, outside the class. */ static GTY(()) varray_type pending_statics; #define pending_statics_used \ (pending_statics ? pending_statics->elements_used : 0) /* A list of functions which were declared inline, but which we may need to emit outline anyway. */ static GTY(()) varray_type deferred_fns; #define deferred_fns_used \ (deferred_fns ? deferred_fns->elements_used : 0) /* Flag used when debugging spew.c */ extern int spew_debug; /* Nonzero if we're done parsing and into end-of-file activities. */ int at_eof; /* Functions called along with real static constructors and destructors. */ tree static_ctors; tree static_dtors; /* Incorporate `const' and `volatile' qualifiers for member functions. FUNCTION is a TYPE_DECL or a FUNCTION_DECL. QUALS is a list of qualifiers. Returns any explicit top-level qualifiers of the method's this pointer, anything other than TYPE_UNQUALIFIED will be an extension. */ int grok_method_quals (tree ctype, tree function, cp_cv_quals quals) { tree fntype = TREE_TYPE (function); tree raises = TYPE_RAISES_EXCEPTIONS (fntype); int type_quals = TYPE_UNQUALIFIED; int this_quals = TYPE_UNQUALIFIED; type_quals = quals & ~TYPE_QUAL_RESTRICT; this_quals = quals & TYPE_QUAL_RESTRICT; ctype = cp_build_qualified_type (ctype, type_quals); fntype = build_method_type_directly (ctype, TREE_TYPE (fntype), (TREE_CODE (fntype) == METHOD_TYPE ? TREE_CHAIN (TYPE_ARG_TYPES (fntype)) : TYPE_ARG_TYPES (fntype))); if (raises) fntype = build_exception_variant (fntype, raises); TREE_TYPE (function) = fntype; return this_quals; } /* Build a PARM_DECL with NAME and TYPE, and set DECL_ARG_TYPE appropriately. */ tree cp_build_parm_decl (tree name, tree type) { tree parm = build_decl (PARM_DECL, name, type); /* DECL_ARG_TYPE is only used by the back end and the back end never sees templates. */ if (!processing_template_decl) DECL_ARG_TYPE (parm) = type_passed_as (type); return parm; } /* Returns a PARM_DECL for a parameter of the indicated TYPE, with the indicated NAME. */ static tree build_artificial_parm (tree name, tree type) { tree parm = cp_build_parm_decl (name, type); DECL_ARTIFICIAL (parm) = 1; /* All our artificial parms are implicitly `const'; they cannot be assigned to. */ TREE_READONLY (parm) = 1; return parm; } /* Constructors for types with virtual baseclasses need an "in-charge" flag saying whether this constructor is responsible for initialization of virtual baseclasses or not. All destructors also need this "in-charge" flag, which additionally determines whether or not the destructor should free the memory for the object. This function adds the "in-charge" flag to member function FN if appropriate. It is called from grokclassfn and tsubst. FN must be either a constructor or destructor. The in-charge flag follows the 'this' parameter, and is followed by the VTT parm (if any), then the user-written parms. */ void maybe_retrofit_in_chrg (tree fn) { tree basetype, arg_types, parms, parm, fntype; /* If we've already add the in-charge parameter don't do it again. */ if (DECL_HAS_IN_CHARGE_PARM_P (fn)) return; /* When processing templates we can't know, in general, whether or not we're going to have virtual baseclasses. */ if (processing_template_decl) return; /* We don't need an in-charge parameter for constructors that don't have virtual bases. */ if (DECL_CONSTRUCTOR_P (fn) && !CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn))) return; arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn)); basetype = TREE_TYPE (TREE_VALUE (arg_types)); arg_types = TREE_CHAIN (arg_types); parms = TREE_CHAIN (DECL_ARGUMENTS (fn)); /* If this is a subobject constructor or destructor, our caller will pass us a pointer to our VTT. */ if (CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn))) { parm = build_artificial_parm (vtt_parm_identifier, vtt_parm_type); /* First add it to DECL_ARGUMENTS between 'this' and the real args... */ TREE_CHAIN (parm) = parms; parms = parm; /* ...and then to TYPE_ARG_TYPES. */ arg_types = hash_tree_chain (vtt_parm_type, arg_types); DECL_HAS_VTT_PARM_P (fn) = 1; } /* Then add the in-charge parm (before the VTT parm). */ parm = build_artificial_parm (in_charge_identifier, integer_type_node); TREE_CHAIN (parm) = parms; parms = parm; arg_types = hash_tree_chain (integer_type_node, arg_types); /* Insert our new parameter(s) into the list. */ TREE_CHAIN (DECL_ARGUMENTS (fn)) = parms; /* And rebuild the function type. */ fntype = build_method_type_directly (basetype, TREE_TYPE (TREE_TYPE (fn)), arg_types); if (TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn))) fntype = build_exception_variant (fntype, TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn))); TREE_TYPE (fn) = fntype; /* Now we've got the in-charge parameter. */ DECL_HAS_IN_CHARGE_PARM_P (fn) = 1; } /* Classes overload their constituent function names automatically. When a function name is declared in a record structure, its name is changed to it overloaded name. Since names for constructors and destructors can conflict, we place a leading '$' for destructors. CNAME is the name of the class we are grokking for. FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'. FLAGS contains bits saying what's special about today's arguments. 1 == DESTRUCTOR. 2 == OPERATOR. If FUNCTION is a destructor, then we must add the `auto-delete' field as a second parameter. There is some hair associated with the fact that we must "declare" this variable in the manner consistent with the way the rest of the arguments were declared. QUALS are the qualifiers for the this pointer. */ void grokclassfn (tree ctype, tree function, enum overload_flags flags, cp_cv_quals quals) { tree fn_name = DECL_NAME (function); cp_cv_quals this_quals = TYPE_UNQUALIFIED; /* Even within an `extern "C"' block, members get C++ linkage. See [dcl.link] for details. */ SET_DECL_LANGUAGE (function, lang_cplusplus); if (fn_name == NULL_TREE) { error ("name missing for member function"); fn_name = get_identifier (""); DECL_NAME (function) = fn_name; } if (quals) this_quals = grok_method_quals (ctype, function, quals); if (TREE_CODE (TREE_TYPE (function)) == METHOD_TYPE) { /* Must add the class instance variable up front. */ /* Right now we just make this a pointer. But later we may wish to make it special. */ tree type = TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (function))); tree qual_type; tree parm; /* The `this' parameter is implicitly `const'; it cannot be assigned to. */ this_quals |= TYPE_QUAL_CONST; qual_type = cp_build_qualified_type (type, this_quals); parm = build_artificial_parm (this_identifier, qual_type); cp_apply_type_quals_to_decl (this_quals, parm); TREE_CHAIN (parm) = DECL_ARGUMENTS (function); DECL_ARGUMENTS (function) = parm; } DECL_CONTEXT (function) = ctype; if (flags == DTOR_FLAG) DECL_DESTRUCTOR_P (function) = 1; if (flags == DTOR_FLAG || DECL_CONSTRUCTOR_P (function)) maybe_retrofit_in_chrg (function); } /* Create an ARRAY_REF, checking for the user doing things backwards along the way. */ tree grok_array_decl (tree array_expr, tree index_exp) { tree type; tree expr; tree orig_array_expr = array_expr; tree orig_index_exp = index_exp; if (error_operand_p (array_expr) || error_operand_p (index_exp)) return error_mark_node; if (processing_template_decl) { if (type_dependent_expression_p (array_expr) || type_dependent_expression_p (index_exp)) return build_min_nt (ARRAY_REF, array_expr, index_exp, NULL_TREE, NULL_TREE); array_expr = build_non_dependent_expr (array_expr); index_exp = build_non_dependent_expr (index_exp); } type = TREE_TYPE (array_expr); gcc_assert (type); type = non_reference (type); /* If they have an `operator[]', use that. */ if (IS_AGGR_TYPE (type) || IS_AGGR_TYPE (TREE_TYPE (index_exp))) expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL, array_expr, index_exp, NULL_TREE, /*overloaded_p=*/NULL); else { tree p1, p2, i1, i2; /* Otherwise, create an ARRAY_REF for a pointer or array type. It is a little-known fact that, if `a' is an array and `i' is an int, you can write `i[a]', which means the same thing as `a[i]'. */ if (TREE_CODE (type) == ARRAY_TYPE) p1 = array_expr; else p1 = build_expr_type_conversion (WANT_POINTER, array_expr, false); if (TREE_CODE (TREE_TYPE (index_exp)) == ARRAY_TYPE) p2 = index_exp; else p2 = build_expr_type_conversion (WANT_POINTER, index_exp, false); i1 = build_expr_type_conversion (WANT_INT | WANT_ENUM, array_expr, false); i2 = build_expr_type_conversion (WANT_INT | WANT_ENUM, index_exp, false); if ((p1 && i2) && (i1 && p2)) error ("ambiguous conversion for array subscript"); if (p1 && i2) array_expr = p1, index_exp = i2; else if (i1 && p2) array_expr = p2, index_exp = i1; else { error ("invalid types %<%T[%T]%> for array subscript", type, TREE_TYPE (index_exp)); return error_mark_node; } if (array_expr == error_mark_node || index_exp == error_mark_node) error ("ambiguous conversion for array subscript"); expr = build_array_ref (array_expr, index_exp); } if (processing_template_decl && expr != error_mark_node) return build_min_non_dep (ARRAY_REF, expr, orig_array_expr, orig_index_exp, NULL_TREE, NULL_TREE); return expr; } /* Given the cast expression EXP, checking out its validity. Either return an error_mark_node if there was an unavoidable error, return a cast to void for trying to delete a pointer w/ the value 0, or return the call to delete. If DOING_VEC is true, we handle things differently for doing an array delete. Implements ARM $5.3.4. This is called from the parser. */ tree delete_sanity (tree exp, tree size, bool doing_vec, int use_global_delete) { tree t, type; if (exp == error_mark_node) return exp; if (processing_template_decl) { t = build_min (DELETE_EXPR, void_type_node, exp, size); DELETE_EXPR_USE_GLOBAL (t) = use_global_delete; DELETE_EXPR_USE_VEC (t) = doing_vec; TREE_SIDE_EFFECTS (t) = 1; return t; } /* An array can't have been allocated by new, so complain. */ if (TREE_CODE (exp) == VAR_DECL && TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) warning ("deleting array %q#D", exp); t = build_expr_type_conversion (WANT_POINTER, exp, true); if (t == NULL_TREE || t == error_mark_node) { error ("type %q#T argument given to %, expected pointer", TREE_TYPE (exp)); return error_mark_node; } type = TREE_TYPE (t); /* As of Valley Forge, you can delete a pointer to const. */ /* You can't delete functions. */ if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE) { error ("cannot delete a function. Only pointer-to-objects are " "valid arguments to %"); return error_mark_node; } /* Deleting ptr to void is undefined behavior [expr.delete/3]. */ if (TREE_CODE (TREE_TYPE (type)) == VOID_TYPE) { warning ("deleting %qT is undefined", type); doing_vec = 0; } /* Deleting a pointer with the value zero is valid and has no effect. */ if (integer_zerop (t)) return build1 (NOP_EXPR, void_type_node, t); if (doing_vec) return build_vec_delete (t, /*maxindex=*/NULL_TREE, sfk_deleting_destructor, use_global_delete); else return build_delete (type, t, sfk_deleting_destructor, LOOKUP_NORMAL, use_global_delete); } /* Report an error if the indicated template declaration is not the sort of thing that should be a member template. */ void check_member_template (tree tmpl) { tree decl; gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL); decl = DECL_TEMPLATE_RESULT (tmpl); if (TREE_CODE (decl) == FUNCTION_DECL || (TREE_CODE (decl) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (decl)))) { if (current_function_decl) /* 14.5.2.2 [temp.mem] A local class shall not have member templates. */ error ("invalid declaration of member template %q#D in local class", decl); if (TREE_CODE (decl) == FUNCTION_DECL && DECL_VIRTUAL_P (decl)) { /* 14.5.2.3 [temp.mem] A member function template shall not be virtual. */ error ("invalid use of % in template declaration of %q#D", decl); DECL_VIRTUAL_P (decl) = 0; } /* The debug-information generating code doesn't know what to do with member templates. */ DECL_IGNORED_P (tmpl) = 1; } else error ("template declaration of %q#D", decl); } /* Return true iff TYPE is a valid Java parameter or return type. */ static bool acceptable_java_type (tree type) { if (TREE_CODE (type) == VOID_TYPE || TYPE_FOR_JAVA (type)) return 1; if (TREE_CODE (type) == POINTER_TYPE || TREE_CODE (type) == REFERENCE_TYPE) { type = TREE_TYPE (type); if (TREE_CODE (type) == RECORD_TYPE) { tree args; int i; if (! TYPE_FOR_JAVA (type)) return false; if (! CLASSTYPE_TEMPLATE_INFO (type)) return true; args = CLASSTYPE_TI_ARGS (type); i = TREE_VEC_LENGTH (args); while (--i >= 0) { type = TREE_VEC_ELT (args, i); if (TREE_CODE (type) == POINTER_TYPE) type = TREE_TYPE (type); if (! TYPE_FOR_JAVA (type)) return false; } return true; } } return false; } /* For a METHOD in a Java class CTYPE, return true if the parameter and return types are valid Java types. Otherwise, print appropriate error messages, and return false. */ bool check_java_method (tree method) { bool jerr = false; tree arg_types = TYPE_ARG_TYPES (TREE_TYPE (method)); tree ret_type = TREE_TYPE (TREE_TYPE (method)); if (!acceptable_java_type (ret_type)) { error ("Java method %qD has non-Java return type %qT", method, ret_type); jerr = true; } arg_types = TREE_CHAIN (arg_types); if (DECL_HAS_IN_CHARGE_PARM_P (method)) arg_types = TREE_CHAIN (arg_types); if (DECL_HAS_VTT_PARM_P (method)) arg_types = TREE_CHAIN (arg_types); for (; arg_types != NULL_TREE; arg_types = TREE_CHAIN (arg_types)) { tree type = TREE_VALUE (arg_types); if (!acceptable_java_type (type)) { error ("Java method %qD has non-Java parameter type %qT", method, type); jerr = true; } } return !jerr; } /* Sanity check: report error if this function FUNCTION is not really a member of the class (CTYPE) it is supposed to belong to. TEMPLATE_PARMS is used to specify the template parameters of a member template passed as FUNCTION_DECL. If the member template is passed as a TEMPLATE_DECL, it can be NULL since the parameters can be extracted from the declaration. If the function is not a function template, it must be NULL. It returns the original declaration for the function, or NULL_TREE if no declaration was found (and an error was emitted). */ tree check_classfn (tree ctype, tree function, tree template_parms) { int ix; bool is_template; if (DECL_USE_TEMPLATE (function) && !(TREE_CODE (function) == TEMPLATE_DECL && DECL_TEMPLATE_SPECIALIZATION (function)) && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (function))) /* Since this is a specialization of a member template, we're not going to find the declaration in the class. For example, in: struct S { template void f(T); }; template <> void S::f(int); we're not going to find `S::f(int)', but there's no reason we should, either. We let our callers know we didn't find the method, but we don't complain. */ return NULL_TREE; /* Basic sanity check: for a template function, the template parameters either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */ if (TREE_CODE (function) == TEMPLATE_DECL) { gcc_assert (!template_parms || comp_template_parms (template_parms, DECL_TEMPLATE_PARMS (function))); template_parms = DECL_TEMPLATE_PARMS (function); } /* OK, is this a definition of a member template? */ is_template = (template_parms != NULL_TREE); ix = class_method_index_for_fn (complete_type (ctype), function); if (ix >= 0) { VEC(tree) *methods = CLASSTYPE_METHOD_VEC (ctype); tree fndecls, fndecl = 0; bool is_conv_op; tree pushed_scope; const char *format = NULL; pushed_scope = push_scope (ctype); for (fndecls = VEC_index (tree, methods, ix); fndecls; fndecls = OVL_NEXT (fndecls)) { tree p1, p2; fndecl = OVL_CURRENT (fndecls); p1 = TYPE_ARG_TYPES (TREE_TYPE (function)); p2 = TYPE_ARG_TYPES (TREE_TYPE (fndecl)); /* We cannot simply call decls_match because this doesn't work for static member functions that are pretending to be methods, and because the name may have been changed by asm("new_name"). */ /* Get rid of the this parameter on functions that become static. */ if (DECL_STATIC_FUNCTION_P (fndecl) && TREE_CODE (TREE_TYPE (function)) == METHOD_TYPE) p1 = TREE_CHAIN (p1); /* A member template definition only matches a member template declaration. */ if (is_template != (TREE_CODE (fndecl) == TEMPLATE_DECL)) continue; if (same_type_p (TREE_TYPE (TREE_TYPE (function)), TREE_TYPE (TREE_TYPE (fndecl))) && compparms (p1, p2) && (!is_template || comp_template_parms (template_parms, DECL_TEMPLATE_PARMS (fndecl))) && (DECL_TEMPLATE_SPECIALIZATION (function) == DECL_TEMPLATE_SPECIALIZATION (fndecl)) && (!DECL_TEMPLATE_SPECIALIZATION (function) || (DECL_TI_TEMPLATE (function) == DECL_TI_TEMPLATE (fndecl)))) break; } if (pushed_scope) pop_scope (pushed_scope); if (fndecls) return OVL_CURRENT (fndecls); error ("prototype for %q#D does not match any in class %qT", function, ctype); is_conv_op = DECL_CONV_FN_P (fndecl); if (is_conv_op) ix = CLASSTYPE_FIRST_CONVERSION_SLOT; fndecls = VEC_index (tree, methods, ix); while (fndecls) { fndecl = OVL_CURRENT (fndecls); fndecls = OVL_NEXT (fndecls); if (!fndecls && is_conv_op) { if (VEC_length (tree, methods) > (size_t) ++ix) { fndecls = VEC_index (tree, methods, ix); if (!DECL_CONV_FN_P (OVL_CURRENT (fndecls))) { fndecls = NULL_TREE; is_conv_op = false; } } else is_conv_op = false; } if (format) format = " %#D"; else if (fndecls) format = "candidates are: %#D"; else format = "candidate is: %#D"; cp_error_at (format, fndecl); } } else if (!COMPLETE_TYPE_P (ctype)) cxx_incomplete_type_error (function, ctype); else error ("no %q#D member function declared in class %qT", function, ctype); /* If we did not find the method in the class, add it to avoid spurious errors (unless the CTYPE is not yet defined, in which case we'll only confuse ourselves when the function is declared properly within the class. */ if (COMPLETE_TYPE_P (ctype)) add_method (ctype, function); return NULL_TREE; } /* DECL is a function with vague linkage. Remember it so that at the end of the translation unit we can decide whether or not to emit it. */ void note_vague_linkage_fn (tree decl) { if (!DECL_DEFERRED_FN (decl)) { DECL_DEFERRED_FN (decl) = 1; DECL_DEFER_OUTPUT (decl) = 1; if (!deferred_fns) VARRAY_TREE_INIT (deferred_fns, 32, "deferred_fns"); VARRAY_PUSH_TREE (deferred_fns, decl); } } /* Like note_vague_linkage_fn but for variables. */ static void note_vague_linkage_var (tree var) { if (!pending_statics) VARRAY_TREE_INIT (pending_statics, 32, "pending_statics"); VARRAY_PUSH_TREE (pending_statics, var); } /* We have just processed the DECL, which is a static data member. Its initializer, if present, is INIT. The ASMSPEC_TREE, if present, is the assembly-language name for the data member. FLAGS is as for cp_finish_decl. */ void finish_static_data_member_decl (tree decl, tree init, tree asmspec_tree, int flags) { gcc_assert (TREE_PUBLIC (decl)); DECL_CONTEXT (decl) = current_class_type; /* We cannot call pushdecl here, because that would fill in the TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do the right thing, namely, to put this decl out straight away. */ /* current_class_type can be NULL_TREE in case of error. */ if (!asmspec_tree && current_class_type) DECL_INITIAL (decl) = error_mark_node; if (! processing_template_decl) note_vague_linkage_var (decl); if (LOCAL_CLASS_P (current_class_type)) pedwarn ("local class %q#T shall not have static data member %q#D", current_class_type, decl); /* Static consts need not be initialized in the class definition. */ if (init != NULL_TREE && TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl))) { static int explained = 0; error ("initializer invalid for static member with constructor"); if (!explained) { error ("(an out of class initialization is required)"); explained = 1; } init = NULL_TREE; } /* Force the compiler to know when an uninitialized static const member is being used. */ if (CP_TYPE_CONST_P (TREE_TYPE (decl)) && init == 0) TREE_USED (decl) = 1; DECL_INITIAL (decl) = init; DECL_IN_AGGR_P (decl) = 1; cp_finish_decl (decl, init, asmspec_tree, flags); } /* Process the specs, declarator (NULL if omitted) and width (NULL if omitted) of a structure component, returning a _DECL node. QUALS is a list of type qualifiers for this decl (such as for declaring const member functions). This is done during the parsing of the struct declaration. The _DECL nodes are chained together and the lot of them are ultimately passed to `build_struct' to make the RECORD_TYPE node. If class A defines that certain functions in class B are friends, then the way I have set things up, it is B who is interested in permission granted by A. However, it is in A's context that these declarations are parsed. By returning a void_type_node, class A does not attempt to incorporate the declarations of the friends within its structure. DO NOT MAKE ANY CHANGES TO THIS CODE WITHOUT MAKING CORRESPONDING CHANGES TO CODE IN `start_method'. */ tree grokfield (const cp_declarator *declarator, cp_decl_specifier_seq *declspecs, tree init, tree asmspec_tree, tree attrlist) { tree value; const char *asmspec = 0; int flags = LOOKUP_ONLYCONVERTING; if (!declspecs->any_specifiers_p && declarator->kind == cdk_id && declarator->u.id.qualifying_scope && TREE_CODE (declarator->u.id.unqualified_name) == IDENTIFIER_NODE) /* Access declaration */ return do_class_using_decl (declarator->u.id.qualifying_scope, declarator->u.id.unqualified_name); if (init && TREE_CODE (init) == TREE_LIST && TREE_VALUE (init) == error_mark_node && TREE_CHAIN (init) == NULL_TREE) init = NULL_TREE; value = grokdeclarator (declarator, declspecs, FIELD, init != 0, &attrlist); if (! value || error_operand_p (value)) /* friend or constructor went bad. */ return error_mark_node; if (TREE_CODE (value) == TYPE_DECL && init) { error ("typedef %qD is initialized (use __typeof__ instead)", value); init = NULL_TREE; } /* Pass friendly classes back. */ if (value == void_type_node) return value; /* Pass friend decls back. */ if ((TREE_CODE (value) == FUNCTION_DECL || TREE_CODE (value) == TEMPLATE_DECL) && DECL_CONTEXT (value) != current_class_type) return value; if (DECL_NAME (value) != NULL_TREE && IDENTIFIER_POINTER (DECL_NAME (value))[0] == '_' && ! strcmp (IDENTIFIER_POINTER (DECL_NAME (value)), "_vptr")) error ("member %qD conflicts with virtual function table field name", value); /* Stash away type declarations. */ if (TREE_CODE (value) == TYPE_DECL) { DECL_NONLOCAL (value) = 1; DECL_CONTEXT (value) = current_class_type; if (processing_template_decl) value = push_template_decl (value); if (attrlist) { /* Avoid storing attributes in template parameters: tsubst is not ready to handle them. */ tree type = TREE_TYPE (value); if (TREE_CODE (type) == TEMPLATE_TYPE_PARM || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM) sorry ("applying attributes to template parameters is not implemented"); else cplus_decl_attributes (&value, attrlist, 0); } return value; } if (DECL_IN_AGGR_P (value)) { error ("%qD is already defined in %qT", value, DECL_CONTEXT (value)); return void_type_node; } if (asmspec_tree) asmspec = TREE_STRING_POINTER (asmspec_tree); if (init) { if (TREE_CODE (value) == FUNCTION_DECL) { /* Initializers for functions are rejected early in the parser. If we get here, it must be a pure specifier for a method. */ gcc_assert (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE); gcc_assert (error_operand_p (init) || integer_zerop (init)); DECL_PURE_VIRTUAL_P (value) = 1; } else if (pedantic && TREE_CODE (value) != VAR_DECL) /* Already complained in grokdeclarator. */ init = NULL_TREE; else { /* We allow initializers to become parameters to base initializers. */ if (TREE_CODE (init) == TREE_LIST) { if (TREE_CHAIN (init) == NULL_TREE) init = TREE_VALUE (init); else init = digest_init (TREE_TYPE (value), init, (tree *)0); } if (!processing_template_decl) { if (TREE_CODE (init) == CONSTRUCTOR) init = digest_init (TREE_TYPE (value), init, (tree *)0); else init = integral_constant_value (init); if (init != error_mark_node && ! TREE_CONSTANT (init)) { /* We can allow references to things that are effectively static, since references are initialized with the address. */ if (TREE_CODE (TREE_TYPE (value)) != REFERENCE_TYPE || (TREE_STATIC (init) == 0 && (!DECL_P (init) || DECL_EXTERNAL (init) == 0))) { error ("field initializer is not constant"); init = error_mark_node; } } } } } if (processing_template_decl && (TREE_CODE (value) == VAR_DECL || TREE_CODE (value) == FUNCTION_DECL)) { value = push_template_decl (value); if (error_operand_p (value)) return error_mark_node; } if (attrlist) cplus_decl_attributes (&value, attrlist, 0); switch (TREE_CODE (value)) { case VAR_DECL: finish_static_data_member_decl (value, init, asmspec_tree, flags); return value; case FIELD_DECL: if (asmspec) error ("% specifiers are not permitted on non-static data members"); if (DECL_INITIAL (value) == error_mark_node) init = error_mark_node; cp_finish_decl (value, init, NULL_TREE, flags); DECL_INITIAL (value) = init; DECL_IN_AGGR_P (value) = 1; return value; case FUNCTION_DECL: if (asmspec) set_user_assembler_name (value, asmspec); if (!DECL_FRIEND_P (value)) grok_special_member_properties (value); cp_finish_decl (value, init, asmspec_tree, flags); /* Pass friends back this way. */ if (DECL_FRIEND_P (value)) return void_type_node; DECL_IN_AGGR_P (value) = 1; return value; default: gcc_unreachable (); } return NULL_TREE; } /* Like `grokfield', but for bitfields. WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */ tree grokbitfield (const cp_declarator *declarator, cp_decl_specifier_seq *declspecs, tree width) { tree value = grokdeclarator (declarator, declspecs, BITFIELD, 0, NULL); if (! value) return NULL_TREE; /* friends went bad. */ /* Pass friendly classes back. */ if (TREE_CODE (value) == VOID_TYPE) return void_type_node; if (TREE_CODE (value) == TYPE_DECL) { error ("cannot declare %qD to be a bit-field type", value); return NULL_TREE; } /* Usually, finish_struct_1 catches bitfields with invalid types. But, in the case of bitfields with function type, we confuse ourselves into thinking they are member functions, so we must check here. */ if (TREE_CODE (value) == FUNCTION_DECL) { error ("cannot declare bit-field %qD with function type", DECL_NAME (value)); return NULL_TREE; } if (DECL_IN_AGGR_P (value)) { error ("%qD is already defined in the class %qT", value, DECL_CONTEXT (value)); return void_type_node; } if (TREE_STATIC (value)) { error ("static member %qD cannot be a bit-field", value); return NULL_TREE; } cp_finish_decl (value, NULL_TREE, NULL_TREE, 0); if (width != error_mark_node) { constant_expression_warning (width); DECL_INITIAL (value) = width; SET_DECL_C_BIT_FIELD (value); } DECL_IN_AGGR_P (value) = 1; return value; } void cplus_decl_attributes (tree *decl, tree attributes, int flags) { if (*decl == NULL_TREE || *decl == void_type_node) return; if (TREE_CODE (*decl) == TEMPLATE_DECL) decl = &DECL_TEMPLATE_RESULT (*decl); decl_attributes (decl, attributes, flags); if (TREE_CODE (*decl) == TYPE_DECL) SET_IDENTIFIER_TYPE_VALUE (DECL_NAME (*decl), TREE_TYPE (*decl)); } /* Walks through the namespace- or function-scope anonymous union OBJECT, with the indicated TYPE, building appropriate ALIAS_DECLs. Returns one of the fields for use in the mangled name. */ static tree build_anon_union_vars (tree type, tree object) { tree main_decl = NULL_TREE; tree field; /* Rather than write the code to handle the non-union case, just give an error. */ if (TREE_CODE (type) != UNION_TYPE) error ("anonymous struct not inside named type"); for (field = TYPE_FIELDS (type); field != NULL_TREE; field = TREE_CHAIN (field)) { tree decl; tree ref; if (DECL_ARTIFICIAL (field)) continue; if (TREE_CODE (field) != FIELD_DECL) { cp_pedwarn_at ("%q#D invalid; an anonymous union can only " "have non-static data members", field); continue; } if (TREE_PRIVATE (field)) cp_pedwarn_at ("private member %q#D in anonymous union", field); else if (TREE_PROTECTED (field)) cp_pedwarn_at ("protected member %q#D in anonymous union", field); if (processing_template_decl) ref = build_min_nt (COMPONENT_REF, object, DECL_NAME (field), NULL_TREE); else ref = build_class_member_access_expr (object, field, NULL_TREE, false); if (DECL_NAME (field)) { decl = build_decl (ALIAS_DECL, DECL_NAME (field), TREE_TYPE (field)); DECL_INITIAL (decl) = ref; TREE_PUBLIC (decl) = 0; TREE_STATIC (decl) = 0; DECL_EXTERNAL (decl) = 1; decl = pushdecl (decl); } else if (ANON_AGGR_TYPE_P (TREE_TYPE (field))) decl = build_anon_union_vars (TREE_TYPE (field), ref); else decl = 0; if (main_decl == NULL_TREE) main_decl = decl; } return main_decl; } /* Finish off the processing of a UNION_TYPE structure. If the union is an anonymous union, then all members must be laid out together. PUBLIC_P is nonzero if this union is not declared static. */ void finish_anon_union (tree anon_union_decl) { tree type; tree main_decl; bool public_p; if (anon_union_decl == error_mark_node) return; type = TREE_TYPE (anon_union_decl); public_p = TREE_PUBLIC (anon_union_decl); /* The VAR_DECL's context is the same as the TYPE's context. */ DECL_CONTEXT (anon_union_decl) = DECL_CONTEXT (TYPE_NAME (type)); if (TYPE_FIELDS (type) == NULL_TREE) return; if (public_p) { error ("namespace-scope anonymous aggregates must be static"); return; } main_decl = build_anon_union_vars (type, anon_union_decl); if (main_decl == NULL_TREE) { warning ("anonymous union with no members"); return; } if (!processing_template_decl) { /* Use main_decl to set the mangled name. */ DECL_NAME (anon_union_decl) = DECL_NAME (main_decl); mangle_decl (anon_union_decl); DECL_NAME (anon_union_decl) = NULL_TREE; } pushdecl (anon_union_decl); if (building_stmt_tree () && at_function_scope_p ()) add_decl_expr (anon_union_decl); else if (!processing_template_decl) rest_of_decl_compilation (anon_union_decl, toplevel_bindings_p (), at_eof); } /* Auxiliary functions to make type signatures for `operator new' and `operator delete' correspond to what compiler will be expecting. */ tree coerce_new_type (tree type) { int e = 0; tree args = TYPE_ARG_TYPES (type); gcc_assert (TREE_CODE (type) == FUNCTION_TYPE); if (!same_type_p (TREE_TYPE (type), ptr_type_node)) { e = 1; error ("% must return type %qT", ptr_type_node); } if (!args || args == void_list_node || !same_type_p (TREE_VALUE (args), size_type_node)) { e = 2; if (args && args != void_list_node) args = TREE_CHAIN (args); pedwarn ("% takes type % (%qT) " "as first parameter", size_type_node); } switch (e) { case 2: args = tree_cons (NULL_TREE, size_type_node, args); /* Fall through. */ case 1: type = build_exception_variant (build_function_type (ptr_type_node, args), TYPE_RAISES_EXCEPTIONS (type)); /* Fall through. */ default:; } return type; } tree coerce_delete_type (tree type) { int e = 0; tree args = TYPE_ARG_TYPES (type); gcc_assert (TREE_CODE (type) == FUNCTION_TYPE); if (!same_type_p (TREE_TYPE (type), void_type_node)) { e = 1; error ("% must return type %qT", void_type_node); } if (!args || args == void_list_node || !same_type_p (TREE_VALUE (args), ptr_type_node)) { e = 2; if (args && args != void_list_node) args = TREE_CHAIN (args); error ("% takes type %qT as first parameter", ptr_type_node); } switch (e) { case 2: args = tree_cons (NULL_TREE, ptr_type_node, args); /* Fall through. */ case 1: type = build_exception_variant (build_function_type (void_type_node, args), TYPE_RAISES_EXCEPTIONS (type)); /* Fall through. */ default:; } return type; } static void mark_vtable_entries (tree decl) { tree entries = CONSTRUCTOR_ELTS (DECL_INITIAL (decl)); for (; entries; entries = TREE_CHAIN (entries)) { tree fnaddr = TREE_VALUE (entries); tree fn; STRIP_NOPS (fnaddr); if (TREE_CODE (fnaddr) != ADDR_EXPR && TREE_CODE (fnaddr) != FDESC_EXPR) /* This entry is an offset: a virtual base class offset, a virtual call offset, an RTTI offset, etc. */ continue; fn = TREE_OPERAND (fnaddr, 0); TREE_ADDRESSABLE (fn) = 1; /* When we don't have vcall offsets, we output thunks whenever we output the vtables that contain them. With vcall offsets, we know all the thunks we'll need when we emit a virtual function, so we emit the thunks there instead. */ if (DECL_THUNK_P (fn)) use_thunk (fn, /*emit_p=*/0); mark_used (fn); } } /* Set DECL up to have the closest approximation of "initialized common" linkage available. */ void comdat_linkage (tree decl) { if (flag_weak) make_decl_one_only (decl); else if (TREE_CODE (decl) == FUNCTION_DECL || (TREE_CODE (decl) == VAR_DECL && DECL_ARTIFICIAL (decl))) /* We can just emit function and compiler-generated variables statically; having multiple copies is (for the most part) only a waste of space. There are two correctness issues, however: the address of a template instantiation with external linkage should be the same, independent of what translation unit asks for the address, and this will not hold when we emit multiple copies of the function. However, there's little else we can do. Also, by default, the typeinfo implementation assumes that there will be only one copy of the string used as the name for each type. Therefore, if weak symbols are unavailable, the run-time library should perform a more conservative check; it should perform a string comparison, rather than an address comparison. */ TREE_PUBLIC (decl) = 0; else { /* Static data member template instantiations, however, cannot have multiple copies. */ if (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node) DECL_COMMON (decl) = 1; else if (EMPTY_CONSTRUCTOR_P (DECL_INITIAL (decl))) { DECL_COMMON (decl) = 1; DECL_INITIAL (decl) = error_mark_node; } else if (!DECL_EXPLICIT_INSTANTIATION (decl)) { /* We can't do anything useful; leave vars for explicit instantiation. */ DECL_EXTERNAL (decl) = 1; DECL_NOT_REALLY_EXTERN (decl) = 0; } } if (DECL_LANG_SPECIFIC (decl)) DECL_COMDAT (decl) = 1; } /* For win32 we also want to put explicit instantiations in linkonce sections, so that they will be merged with implicit instantiations; otherwise we get duplicate symbol errors. For Darwin we do not want explicit instantiations to be linkonce. */ void maybe_make_one_only (tree decl) { /* We used to say that this was not necessary on targets that support weak symbols, because the implicit instantiations will defer to the explicit one. However, that's not actually the case in SVR4; a strong definition after a weak one is an error. Also, not making explicit instantiations one_only means that we can end up with two copies of some template instantiations. */ if (! flag_weak) return; /* We can't set DECL_COMDAT on functions, or cp_finish_file will think we can get away with not emitting them if they aren't used. We need to for variables so that cp_finish_decl will update their linkage, because their DECL_INITIAL may not have been set properly yet. */ if (!TARGET_WEAK_NOT_IN_ARCHIVE_TOC || (! DECL_EXPLICIT_INSTANTIATION (decl) && ! DECL_TEMPLATE_SPECIALIZATION (decl))) { make_decl_one_only (decl); if (TREE_CODE (decl) == VAR_DECL) { DECL_COMDAT (decl) = 1; /* Mark it needed so we don't forget to emit it. */ mark_decl_referenced (decl); } } } /* Determine whether or not we want to specifically import or export CTYPE, using various heuristics. */ static void import_export_class (tree ctype) { /* -1 for imported, 1 for exported. */ int import_export = 0; /* It only makes sense to call this function at EOF. The reason is that this function looks at whether or not the first non-inline non-abstract virtual member function has been defined in this translation unit. But, we can't possibly know that until we've seen the entire translation unit. */ gcc_assert (at_eof); if (CLASSTYPE_INTERFACE_KNOWN (ctype)) return; /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface, we will have CLASSTYPE_INTERFACE_ONLY set but not CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this heuristic because someone will supply a #pragma implementation elsewhere, and deducing it here would produce a conflict. */ if (CLASSTYPE_INTERFACE_ONLY (ctype)) return; if (lookup_attribute ("dllimport", TYPE_ATTRIBUTES (ctype))) import_export = -1; else if (lookup_attribute ("dllexport", TYPE_ATTRIBUTES (ctype))) import_export = 1; else if (CLASSTYPE_IMPLICIT_INSTANTIATION (ctype) && !flag_implicit_templates) /* For a template class, without -fimplicit-templates, check the repository. If the virtual table is assigned to this translation unit, then export the class; otherwise, import it. */ import_export = repo_export_class_p (ctype) ? 1 : -1; else if (TYPE_POLYMORPHIC_P (ctype)) { /* The ABI specifies that the virtual table and associated information are emitted with the key method, if any. */ tree method = CLASSTYPE_KEY_METHOD (ctype); /* If weak symbol support is not available, then we must be careful not to emit the vtable when the key function is inline. An inline function can be defined in multiple translation units. If we were to emit the vtable in each translation unit containing a definition, we would get multiple definition errors at link-time. */ if (method && (flag_weak || ! DECL_DECLARED_INLINE_P (method))) import_export = (DECL_REALLY_EXTERN (method) ? -1 : 1); } /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing a definition anywhere else. */ if (MULTIPLE_SYMBOL_SPACES && import_export == -1) import_export = 0; /* Allow backends the chance to overrule the decision. */ if (targetm.cxx.import_export_class) import_export = targetm.cxx.import_export_class (ctype, import_export); if (import_export) { SET_CLASSTYPE_INTERFACE_KNOWN (ctype); CLASSTYPE_INTERFACE_ONLY (ctype) = (import_export < 0); } } /* Return true if VAR has already been provided to the back end; in that case VAR should not be modified further by the front end. */ static bool var_finalized_p (tree var) { return cgraph_varpool_node (var)->finalized; } /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason, must be emitted in this translation unit. Mark it as such. */ void mark_needed (tree decl) { /* It's possible that we no longer need to set TREE_SYMBOL_REFERENCED here directly, but doing so is harmless. */ TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)) = 1; mark_decl_referenced (decl); } /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function returns true if a definition of this entity should be provided in this object file. Callers use this function to determine whether or not to let the back end know that a definition of DECL is available in this translation unit. */ bool decl_needed_p (tree decl) { gcc_assert (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL); /* This function should only be called at the end of the translation unit. We cannot be sure of whether or not something will be COMDAT until that point. */ gcc_assert (at_eof); /* All entities with external linkage that are not COMDAT should be emitted; they may be referred to from other object files. */ if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl)) return true; /* If this entity was used, let the back-end see it; it will decide whether or not to emit it into the object file. */ if (TREE_USED (decl) || (DECL_ASSEMBLER_NAME_SET_P (decl) && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))) return true; /* Otherwise, DECL does not need to be emitted -- yet. A subsequent reference to DECL might cause it to be emitted later. */ return false; } /* If necessary, write out the vtables for the dynamic class CTYPE. Returns true if any vtables were emitted. */ static bool maybe_emit_vtables (tree ctype) { tree vtbl; tree primary_vtbl; int needed = 0; /* If the vtables for this class have already been emitted there is nothing more to do. */ primary_vtbl = CLASSTYPE_VTABLES (ctype); if (var_finalized_p (primary_vtbl)) return false; /* Ignore dummy vtables made by get_vtable_decl. */ if (TREE_TYPE (primary_vtbl) == void_type_node) return false; /* On some targets, we cannot determine the key method until the end of the translation unit -- which is when this function is called. */ if (!targetm.cxx.key_method_may_be_inline ()) determine_key_method (ctype); /* See if any of the vtables are needed. */ for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = TREE_CHAIN (vtbl)) { import_export_decl (vtbl); if (DECL_NOT_REALLY_EXTERN (vtbl) && decl_needed_p (vtbl)) needed = 1; } if (!needed) { /* If the references to this class' vtables are optimized away, still emit the appropriate debugging information. See dfs_debug_mark. */ if (DECL_COMDAT (primary_vtbl) && CLASSTYPE_DEBUG_REQUESTED (ctype)) note_debug_info_needed (ctype); return false; } /* The ABI requires that we emit all of the vtables if we emit any of them. */ for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = TREE_CHAIN (vtbl)) { /* Mark entities references from the virtual table as used. */ mark_vtable_entries (vtbl); if (TREE_TYPE (DECL_INITIAL (vtbl)) == 0) { tree expr = store_init_value (vtbl, DECL_INITIAL (vtbl)); /* It had better be all done at compile-time. */ gcc_assert (!expr); } /* Write it out. */ DECL_EXTERNAL (vtbl) = 0; rest_of_decl_compilation (vtbl, 1, 1); /* Because we're only doing syntax-checking, we'll never end up actually marking the variable as written. */ if (flag_syntax_only) TREE_ASM_WRITTEN (vtbl) = 1; } /* Since we're writing out the vtable here, also write the debug info. */ note_debug_info_needed (ctype); return true; } /* Like c_determine_visibility, but with additional C++-specific behavior. */ void determine_visibility (tree decl) { tree class_type; /* Cloned constructors and destructors get the same visibility as the underlying function. That should be set up in maybe_clone_body. */ gcc_assert (!DECL_CLONED_FUNCTION_P (decl)); /* Give the common code a chance to make a determination. */ if (c_determine_visibility (decl)) return; /* If DECL is a member of a class, visibility specifiers on the class can influence the visibility of the DECL. */ if (DECL_CLASS_SCOPE_P (decl)) class_type = DECL_CONTEXT (decl); else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl) && CLASS_TYPE_P (TREE_TYPE (DECL_NAME (decl)))) class_type = TREE_TYPE (DECL_NAME (decl)); else { /* Virtual tables have DECL_CONTEXT set to their associated class, so they are automatically handled above. */ gcc_assert (TREE_CODE (decl) != VAR_DECL || !DECL_VTABLE_OR_VTT_P (decl)); /* Entities not associated with any class just get the visibility specified by their attributes. */ return; } /* By default, static data members and function members receive the visibility of their containing class. */ if (class_type) { if (TARGET_DLLIMPORT_DECL_ATTRIBUTES && lookup_attribute ("dllexport", TYPE_ATTRIBUTES (class_type))) { DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT; DECL_VISIBILITY_SPECIFIED (decl) = 1; } else if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl) && visibility_options.inlines_hidden) { DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN; DECL_VISIBILITY_SPECIFIED (decl) = 1; } else if (CLASSTYPE_VISIBILITY_SPECIFIED (class_type)) { DECL_VISIBILITY (decl) = CLASSTYPE_VISIBILITY (class_type); DECL_VISIBILITY_SPECIFIED (decl) = 1; } /* If no explicit visibility information has been provided for this class, some targets require that class data be exported. */ else if (TREE_CODE (decl) == VAR_DECL && targetm.cxx.export_class_data () && (DECL_TINFO_P (decl) || (DECL_VTABLE_OR_VTT_P (decl) /* Construction virtual tables are not emitted because they cannot be referred to from other object files; their name is not standardized by the ABI. */ && !DECL_CONSTRUCTION_VTABLE_P (decl)))) DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT; else { DECL_VISIBILITY (decl) = CLASSTYPE_VISIBILITY (class_type); DECL_VISIBILITY_SPECIFIED (decl) = 0; } } } /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage for DECL has not already been determined, do so now by setting DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this function is called entities with vague linkage whose definitions are available must have TREE_PUBLIC set. If this function decides to place DECL in COMDAT, it will set appropriate flags -- but will not clear DECL_EXTERNAL. It is up to the caller to decide whether or not to clear DECL_EXTERNAL. Some callers defer that decision until it is clear that DECL is actually required. */ void import_export_decl (tree decl) { int emit_p; bool comdat_p; bool import_p; if (DECL_INTERFACE_KNOWN (decl)) return; /* We cannot determine what linkage to give to an entity with vague linkage until the end of the file. For example, a virtual table for a class will be defined if and only if the key method is defined in this translation unit. As a further example, consider that when compiling a translation unit that uses PCH file with "-frepo" it would be incorrect to make decisions about what entities to emit when building the PCH; those decisions must be delayed until the repository information has been processed. */ gcc_assert (at_eof); /* Object file linkage for explicit instantiations is handled in mark_decl_instantiated. For static variables in functions with vague linkage, maybe_commonize_var is used. Therefore, the only declarations that should be provided to this function are those with external linkage that are: * implicit instantiations of function templates * inline function * implicit instantiations of static data members of class templates * virtual tables * typeinfo objects Furthermore, all entities that reach this point must have a definition available in this translation unit. The following assertions check these conditions. */ gcc_assert (TREE_CODE (decl) == FUNCTION_DECL || TREE_CODE (decl) == VAR_DECL); /* Any code that creates entities with TREE_PUBLIC cleared should also set DECL_INTERFACE_KNOWN. */ gcc_assert (TREE_PUBLIC (decl)); if (TREE_CODE (decl) == FUNCTION_DECL) gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl) || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl) || DECL_DECLARED_INLINE_P (decl)); else gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl) || DECL_VTABLE_OR_VTT_P (decl) || DECL_TINFO_P (decl)); /* Check that a definition of DECL is available in this translation unit. */ gcc_assert (!DECL_REALLY_EXTERN (decl)); /* Assume that DECL will not have COMDAT linkage. */ comdat_p = false; /* Assume that DECL will not be imported into this translation unit. */ import_p = false; /* See if the repository tells us whether or not to emit DECL in this translation unit. */ emit_p = repo_emit_p (decl); if (emit_p == 0) import_p = true; else if (emit_p == 1) { /* The repository indicates that this entity should be defined here. Make sure the back end honors that request. */ if (TREE_CODE (decl) == VAR_DECL) mark_needed (decl); else if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl) || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (decl)) { tree clone; FOR_EACH_CLONE (clone, decl) mark_needed (clone); } else mark_needed (decl); /* Output the definition as an ordinary strong definition. */ DECL_EXTERNAL (decl) = 0; DECL_INTERFACE_KNOWN (decl) = 1; return; } if (import_p) /* We have already decided what to do with this DECL; there is no need to check anything further. */ ; else if (TREE_CODE (decl) == VAR_DECL && DECL_VTABLE_OR_VTT_P (decl)) { tree type = DECL_CONTEXT (decl); import_export_class (type); if (TYPE_FOR_JAVA (type)) import_p = true; else if (CLASSTYPE_INTERFACE_KNOWN (type) && CLASSTYPE_INTERFACE_ONLY (type)) import_p = true; else if ((!flag_weak || TARGET_WEAK_NOT_IN_ARCHIVE_TOC) && !CLASSTYPE_USE_TEMPLATE (type) && CLASSTYPE_KEY_METHOD (type) && !DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (type))) /* The ABI requires that all virtual tables be emitted with COMDAT linkage. However, on systems where COMDAT symbols don't show up in the table of contents for a static archive, or on systems without weak symbols (where we approximate COMDAT linkage by using internal linkage), the linker will report errors about undefined symbols because it will not see the virtual table definition. Therefore, in the case that we know that the virtual table will be emitted in only one translation unit, we make the virtual table an ordinary definition with external linkage. */ DECL_EXTERNAL (decl) = 0; else if (CLASSTYPE_INTERFACE_KNOWN (type)) { /* TYPE is being exported from this translation unit, so DECL should be defined here. */ if (!flag_weak && CLASSTYPE_EXPLICIT_INSTANTIATION (type)) /* If a class is declared in a header with the "extern template" extension, then it will not be instantiated, even in translation units that would normally require it. Often such classes are explicitly instantiated in one translation unit. Therefore, the explicit instantiation must be made visible to other translation units. */ DECL_EXTERNAL (decl) = 0; else { /* The ABI requires COMDAT linkage. Normally, we only emit COMDAT things when they are needed; make sure that we realize that this entity is indeed needed. */ comdat_p = true; mark_needed (decl); } } else if (!flag_implicit_templates && CLASSTYPE_IMPLICIT_INSTANTIATION (type)) import_p = true; else comdat_p = true; } else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl)) { tree type = TREE_TYPE (DECL_NAME (decl)); if (CLASS_TYPE_P (type)) { import_export_class (type); if (CLASSTYPE_INTERFACE_KNOWN (type) && TYPE_POLYMORPHIC_P (type) && CLASSTYPE_INTERFACE_ONLY (type) /* If -fno-rtti was specified, then we cannot be sure that RTTI information will be emitted with the virtual table of the class, so we must emit it wherever it is used. */ && flag_rtti) import_p = true; else { comdat_p = true; if (CLASSTYPE_INTERFACE_KNOWN (type) && !CLASSTYPE_INTERFACE_ONLY (type)) { mark_needed (decl); if (!flag_weak) { comdat_p = false; DECL_EXTERNAL (decl) = 0; } } } } else comdat_p = true; } else if (DECL_TEMPLATE_INSTANTIATION (decl) || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)) { /* DECL is an implicit instantiation of a function or static data member. */ if (flag_implicit_templates || (flag_implicit_inline_templates && TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl))) comdat_p = true; else /* If we are not implicitly generating templates, then mark this entity as undefined in this translation unit. */ import_p = true; } else if (DECL_FUNCTION_MEMBER_P (decl)) { if (!DECL_DECLARED_INLINE_P (decl)) { tree ctype = DECL_CONTEXT (decl); import_export_class (ctype); if (CLASSTYPE_INTERFACE_KNOWN (ctype)) { DECL_NOT_REALLY_EXTERN (decl) = ! (CLASSTYPE_INTERFACE_ONLY (ctype) || (DECL_DECLARED_INLINE_P (decl) && ! flag_implement_inlines && !DECL_VINDEX (decl))); if (!DECL_NOT_REALLY_EXTERN (decl)) DECL_EXTERNAL (decl) = 1; /* Always make artificials weak. */ if (DECL_ARTIFICIAL (decl) && flag_weak) comdat_p = true; else maybe_make_one_only (decl); } } else comdat_p = true; } else comdat_p = true; if (import_p) { /* If we are importing DECL into this translation unit, mark is an undefined here. */ DECL_EXTERNAL (decl) = 1; DECL_NOT_REALLY_EXTERN (decl) = 0; } else if (comdat_p) { /* If we decided to put DECL in COMDAT, mark it accordingly at this point. */ comdat_linkage (decl); } DECL_INTERFACE_KNOWN (decl) = 1; } /* Return an expression that performs the destruction of DECL, which must be a VAR_DECL whose type has a non-trivial destructor, or is an array whose (innermost) elements have a non-trivial destructor. */ tree build_cleanup (tree decl) { tree temp; tree type = TREE_TYPE (decl); /* This function should only be called for declarations that really require cleanups. */ gcc_assert (!TYPE_HAS_TRIVIAL_DESTRUCTOR (type)); /* Treat all objects with destructors as used; the destructor may do something substantive. */ mark_used (decl); if (TREE_CODE (type) == ARRAY_TYPE) temp = decl; else { cxx_mark_addressable (decl); temp = build1 (ADDR_EXPR, build_pointer_type (type), decl); } temp = build_delete (TREE_TYPE (temp), temp, sfk_complete_destructor, LOOKUP_NORMAL|LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR, 0); return temp; } /* Returns the initialization guard variable for the variable DECL, which has static storage duration. */ tree get_guard (tree decl) { tree sname; tree guard; sname = mangle_guard_variable (decl); guard = IDENTIFIER_GLOBAL_VALUE (sname); if (! guard) { tree guard_type; /* We use a type that is big enough to contain a mutex as well as an integer counter. */ guard_type = targetm.cxx.guard_type (); guard = build_decl (VAR_DECL, sname, guard_type); /* The guard should have the same linkage as what it guards. */ TREE_PUBLIC (guard) = TREE_PUBLIC (decl); TREE_STATIC (guard) = TREE_STATIC (decl); DECL_COMMON (guard) = DECL_COMMON (decl); DECL_ONE_ONLY (guard) = DECL_ONE_ONLY (decl); if (TREE_PUBLIC (decl)) DECL_WEAK (guard) = DECL_WEAK (decl); DECL_ARTIFICIAL (guard) = 1; DECL_IGNORED_P (guard) = 1; TREE_USED (guard) = 1; pushdecl_top_level_and_finish (guard, NULL_TREE); } return guard; } /* Return those bits of the GUARD variable that should be set when the guarded entity is actually initialized. */ static tree get_guard_bits (tree guard) { if (!targetm.cxx.guard_mask_bit ()) { /* We only set the first byte of the guard, in order to leave room for a mutex in the high-order bits. */ guard = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (guard)), guard); guard = build1 (NOP_EXPR, build_pointer_type (char_type_node), guard); guard = build1 (INDIRECT_REF, char_type_node, guard); } return guard; } /* Return an expression which determines whether or not the GUARD variable has already been initialized. */ tree get_guard_cond (tree guard) { tree guard_value; /* Check to see if the GUARD is zero. */ guard = get_guard_bits (guard); /* Mask off all but the low bit. */ if (targetm.cxx.guard_mask_bit ()) { guard_value = integer_one_node; if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard))) guard_value = convert (TREE_TYPE (guard), guard_value); guard = cp_build_binary_op (BIT_AND_EXPR, guard, guard_value); } guard_value = integer_zero_node; if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard))) guard_value = convert (TREE_TYPE (guard), guard_value); return cp_build_binary_op (EQ_EXPR, guard, guard_value); } /* Return an expression which sets the GUARD variable, indicating that the variable being guarded has been initialized. */ tree set_guard (tree guard) { tree guard_init; /* Set the GUARD to one. */ guard = get_guard_bits (guard); guard_init = integer_one_node; if (!same_type_p (TREE_TYPE (guard_init), TREE_TYPE (guard))) guard_init = convert (TREE_TYPE (guard), guard_init); return build_modify_expr (guard, NOP_EXPR, guard_init); } /* Start the process of running a particular set of global constructors or destructors. Subroutine of do_[cd]tors. */ static tree start_objects (int method_type, int initp) { tree body; tree fndecl; char type[10]; /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */ if (initp != DEFAULT_INIT_PRIORITY) { char joiner; #ifdef JOINER joiner = JOINER; #else joiner = '_'; #endif sprintf (type, "%c%c%.5u", method_type, joiner, initp); } else sprintf (type, "%c", method_type); fndecl = build_lang_decl (FUNCTION_DECL, get_file_function_name_long (type), build_function_type (void_type_node, void_list_node)); start_preparsed_function (fndecl, /*attrs=*/NULL_TREE, SF_PRE_PARSED); /* It can be a static function as long as collect2 does not have to scan the object file to find its ctor/dtor routine. */ TREE_PUBLIC (current_function_decl) = ! targetm.have_ctors_dtors; /* Mark this declaration as used to avoid spurious warnings. */ TREE_USED (current_function_decl) = 1; /* Mark this function as a global constructor or destructor. */ if (method_type == 'I') DECL_GLOBAL_CTOR_P (current_function_decl) = 1; else DECL_GLOBAL_DTOR_P (current_function_decl) = 1; DECL_LANG_SPECIFIC (current_function_decl)->decl_flags.u2sel = 1; body = begin_compound_stmt (BCS_FN_BODY); /* We cannot allow these functions to be elided, even if they do not have external linkage. And, there's no point in deferring compilation of thes functions; they're all going to have to be out anyhow. */ DECL_INLINE (current_function_decl) = 0; DECL_UNINLINABLE (current_function_decl) = 1; return body; } /* Finish the process of running a particular set of global constructors or destructors. Subroutine of do_[cd]tors. */ static void finish_objects (int method_type, int initp, tree body) { tree fn; /* Finish up. */ finish_compound_stmt (body); fn = finish_function (0); expand_or_defer_fn (fn); /* When only doing semantic analysis, and no RTL generation, we can't call functions that directly emit assembly code; there is no assembly file in which to put the code. */ if (flag_syntax_only) return; if (targetm.have_ctors_dtors) { rtx fnsym = XEXP (DECL_RTL (fn), 0); if (method_type == 'I') (* targetm.asm_out.constructor) (fnsym, initp); else (* targetm.asm_out.destructor) (fnsym, initp); } } /* The names of the parameters to the function created to handle initializations and destructions for objects with static storage duration. */ #define INITIALIZE_P_IDENTIFIER "__initialize_p" #define PRIORITY_IDENTIFIER "__priority" /* The name of the function we create to handle initializations and destructions for objects with static storage duration. */ #define SSDF_IDENTIFIER "__static_initialization_and_destruction" /* The declaration for the __INITIALIZE_P argument. */ static GTY(()) tree initialize_p_decl; /* The declaration for the __PRIORITY argument. */ static GTY(()) tree priority_decl; /* The declaration for the static storage duration function. */ static GTY(()) tree ssdf_decl; /* All the static storage duration functions created in this translation unit. */ static GTY(()) varray_type ssdf_decls; /* A map from priority levels to information about that priority level. There may be many such levels, so efficient lookup is important. */ static splay_tree priority_info_map; /* Begins the generation of the function that will handle all initialization and destruction of objects with static storage duration. The function generated takes two parameters of type `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is nonzero, it performs initializations. Otherwise, it performs destructions. It only performs those initializations or destructions with the indicated __PRIORITY. The generated function returns no value. It is assumed that this function will only be called once per translation unit. */ static tree start_static_storage_duration_function (unsigned count) { tree parm_types; tree type; tree body; char id[sizeof (SSDF_IDENTIFIER) + 1 /* '\0' */ + 32]; /* Create the identifier for this function. It will be of the form SSDF_IDENTIFIER_. */ sprintf (id, "%s_%u", SSDF_IDENTIFIER, count); /* Create the parameters. */ parm_types = void_list_node; parm_types = tree_cons (NULL_TREE, integer_type_node, parm_types); parm_types = tree_cons (NULL_TREE, integer_type_node, parm_types); type = build_function_type (void_type_node, parm_types); /* Create the FUNCTION_DECL itself. */ ssdf_decl = build_lang_decl (FUNCTION_DECL, get_identifier (id), type); TREE_PUBLIC (ssdf_decl) = 0; DECL_ARTIFICIAL (ssdf_decl) = 1; /* Put this function in the list of functions to be called from the static constructors and destructors. */ if (!ssdf_decls) { VARRAY_TREE_INIT (ssdf_decls, 32, "ssdf_decls"); /* Take this opportunity to initialize the map from priority numbers to information about that priority level. */ priority_info_map = splay_tree_new (splay_tree_compare_ints, /*delete_key_fn=*/0, /*delete_value_fn=*/ (splay_tree_delete_value_fn) &free); /* We always need to generate functions for the DEFAULT_INIT_PRIORITY so enter it now. That way when we walk priorities later, we'll be sure to find the DEFAULT_INIT_PRIORITY. */ get_priority_info (DEFAULT_INIT_PRIORITY); } VARRAY_PUSH_TREE (ssdf_decls, ssdf_decl); /* Create the argument list. */ initialize_p_decl = cp_build_parm_decl (get_identifier (INITIALIZE_P_IDENTIFIER), integer_type_node); DECL_CONTEXT (initialize_p_decl) = ssdf_decl; TREE_USED (initialize_p_decl) = 1; priority_decl = cp_build_parm_decl (get_identifier (PRIORITY_IDENTIFIER), integer_type_node); DECL_CONTEXT (priority_decl) = ssdf_decl; TREE_USED (priority_decl) = 1; TREE_CHAIN (initialize_p_decl) = priority_decl; DECL_ARGUMENTS (ssdf_decl) = initialize_p_decl; /* Put the function in the global scope. */ pushdecl (ssdf_decl); /* Start the function itself. This is equivalent to declaring the function as: static void __ssdf (int __initialize_p, init __priority_p); It is static because we only need to call this function from the various constructor and destructor functions for this module. */ start_preparsed_function (ssdf_decl, /*attrs=*/NULL_TREE, SF_PRE_PARSED); /* Set up the scope of the outermost block in the function. */ body = begin_compound_stmt (BCS_FN_BODY); /* This function must not be deferred because we are depending on its compilation to tell us what is TREE_SYMBOL_REFERENCED. */ DECL_INLINE (ssdf_decl) = 0; DECL_UNINLINABLE (ssdf_decl) = 1; return body; } /* Finish the generation of the function which performs initialization and destruction of objects with static storage duration. After this point, no more such objects can be created. */ static void finish_static_storage_duration_function (tree body) { /* Close out the function. */ finish_compound_stmt (body); expand_or_defer_fn (finish_function (0)); } /* Return the information about the indicated PRIORITY level. If no code to handle this level has yet been generated, generate the appropriate prologue. */ static priority_info get_priority_info (int priority) { priority_info pi; splay_tree_node n; n = splay_tree_lookup (priority_info_map, (splay_tree_key) priority); if (!n) { /* Create a new priority information structure, and insert it into the map. */ pi = xmalloc (sizeof (struct priority_info_s)); pi->initializations_p = 0; pi->destructions_p = 0; splay_tree_insert (priority_info_map, (splay_tree_key) priority, (splay_tree_value) pi); } else pi = (priority_info) n->value; return pi; } /* Set up to handle the initialization or destruction of DECL. If INITP is nonzero, we are initializing the variable. Otherwise, we are destroying it. */ static tree start_static_initialization_or_destruction (tree decl, int initp) { tree guard_if_stmt = NULL_TREE; int priority; tree cond; tree guard; tree init_cond; priority_info pi; /* Figure out the priority for this declaration. */ priority = DECL_INIT_PRIORITY (decl); if (!priority) priority = DEFAULT_INIT_PRIORITY; /* Remember that we had an initialization or finalization at this priority. */ pi = get_priority_info (priority); if (initp) pi->initializations_p = 1; else pi->destructions_p = 1; /* Trick the compiler into thinking we are at the file and line where DECL was declared so that error-messages make sense, and so that the debugger will show somewhat sensible file and line information. */ input_location = DECL_SOURCE_LOCATION (decl); /* Because of: [class.access.spec] Access control for implicit calls to the constructors, the conversion functions, or the destructor called to create and destroy a static data member is performed as if these calls appeared in the scope of the member's class. we pretend we are in a static member function of the class of which the DECL is a member. */ if (member_p (decl)) { DECL_CONTEXT (current_function_decl) = DECL_CONTEXT (decl); DECL_STATIC_FUNCTION_P (current_function_decl) = 1; } /* Conditionalize this initialization on being in the right priority and being initializing/finalizing appropriately. */ guard_if_stmt = begin_if_stmt (); cond = cp_build_binary_op (EQ_EXPR, priority_decl, build_int_cst (NULL_TREE, priority)); init_cond = initp ? integer_one_node : integer_zero_node; init_cond = cp_build_binary_op (EQ_EXPR, initialize_p_decl, init_cond); cond = cp_build_binary_op (TRUTH_ANDIF_EXPR, cond, init_cond); /* Assume we don't need a guard. */ guard = NULL_TREE; /* We need a guard if this is an object with external linkage that might be initialized in more than one place. (For example, a static data member of a template, when the data member requires construction.) */ if (TREE_PUBLIC (decl) && (DECL_COMMON (decl) || DECL_ONE_ONLY (decl) || DECL_WEAK (decl))) { tree guard_cond; guard = get_guard (decl); /* When using __cxa_atexit, we just check the GUARD as we would for a local static. */ if (flag_use_cxa_atexit) { /* When using __cxa_atexit, we never try to destroy anything from a static destructor. */ gcc_assert (initp); guard_cond = get_guard_cond (guard); } /* If we don't have __cxa_atexit, then we will be running destructors from .fini sections, or their equivalents. So, we need to know how many times we've tried to initialize this object. We do initializations only if the GUARD is zero, i.e., if we are the first to initialize the variable. We do destructions only if the GUARD is one, i.e., if we are the last to destroy the variable. */ else if (initp) guard_cond = cp_build_binary_op (EQ_EXPR, build_unary_op (PREINCREMENT_EXPR, guard, /*noconvert=*/1), integer_one_node); else guard_cond = cp_build_binary_op (EQ_EXPR, build_unary_op (PREDECREMENT_EXPR, guard, /*noconvert=*/1), integer_zero_node); cond = cp_build_binary_op (TRUTH_ANDIF_EXPR, cond, guard_cond); } finish_if_stmt_cond (cond, guard_if_stmt); /* If we're using __cxa_atexit, we have not already set the GUARD, so we must do so now. */ if (guard && initp && flag_use_cxa_atexit) finish_expr_stmt (set_guard (guard)); return guard_if_stmt; } /* We've just finished generating code to do an initialization or finalization. GUARD_IF_STMT is the if-statement we used to guard the initialization. */ static void finish_static_initialization_or_destruction (tree guard_if_stmt) { finish_then_clause (guard_if_stmt); finish_if_stmt (guard_if_stmt); /* Now that we're done with DECL we don't need to pretend to be a member of its class any longer. */ DECL_CONTEXT (current_function_decl) = NULL_TREE; DECL_STATIC_FUNCTION_P (current_function_decl) = 0; } /* Generate code to do the initialization of DECL, a VAR_DECL with static storage duration. The initialization is INIT. */ static void do_static_initialization (tree decl, tree init) { tree guard_if_stmt; /* Set up for the initialization. */ guard_if_stmt = start_static_initialization_or_destruction (decl, /*initp=*/1); /* Perform the initialization. */ if (init) finish_expr_stmt (init); /* If we're using __cxa_atexit, register a function that calls the destructor for the object. */ if (flag_use_cxa_atexit) finish_expr_stmt (register_dtor_fn (decl)); /* Finish up. */ finish_static_initialization_or_destruction (guard_if_stmt); } /* Generate code to do the static destruction of DECL. If DECL may be initialized more than once in different object files, GUARD is the guard variable to check. PRIORITY is the priority for the destruction. */ static void do_static_destruction (tree decl) { tree guard_if_stmt; /* If we're using __cxa_atexit, then destructors are registered immediately after objects are initialized. */ gcc_assert (!flag_use_cxa_atexit); /* If we don't need a destructor, there's nothing to do. */ if (TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl))) return; /* Actually do the destruction. */ guard_if_stmt = start_static_initialization_or_destruction (decl, /*initp=*/0); finish_expr_stmt (build_cleanup (decl)); finish_static_initialization_or_destruction (guard_if_stmt); } /* VARS is a list of variables with static storage duration which may need initialization and/or finalization. Remove those variables that don't really need to be initialized or finalized, and return the resulting list. The order in which the variables appear in VARS is in reverse order of the order in which they should actually be initialized. The list we return is in the unreversed order; i.e., the first variable should be initialized first. */ static tree prune_vars_needing_no_initialization (tree *vars) { tree *var = vars; tree result = NULL_TREE; while (*var) { tree t = *var; tree decl = TREE_VALUE (t); tree init = TREE_PURPOSE (t); /* Deal gracefully with error. */ if (decl == error_mark_node) { var = &TREE_CHAIN (t); continue; } /* The only things that can be initialized are variables. */ gcc_assert (TREE_CODE (decl) == VAR_DECL); /* If this object is not defined, we don't need to do anything here. */ if (DECL_EXTERNAL (decl)) { var = &TREE_CHAIN (t); continue; } /* Also, if the initializer already contains errors, we can bail out now. */ if (init && TREE_CODE (init) == TREE_LIST && value_member (error_mark_node, init)) { var = &TREE_CHAIN (t); continue; } /* This variable is going to need initialization and/or finalization, so we add it to the list. */ *var = TREE_CHAIN (t); TREE_CHAIN (t) = result; result = t; } return result; } /* Make sure we have told the back end about all the variables in VARS. */ static void write_out_vars (tree vars) { tree v; for (v = vars; v; v = TREE_CHAIN (v)) { tree var = TREE_VALUE (v); if (!var_finalized_p (var)) { import_export_decl (var); rest_of_decl_compilation (var, 1, 1); } } } /* Generate a static constructor (if CONSTRUCTOR_P) or destructor (otherwise) that will initialize all gobal objects with static storage duration having the indicated PRIORITY. */ static void generate_ctor_or_dtor_function (bool constructor_p, int priority, location_t *locus) { char function_key; tree arguments; tree fndecl; tree body; size_t i; input_location = *locus; #ifdef USE_MAPPED_LOCATION /* ??? */ #else locus->line++; #endif /* We use `I' to indicate initialization and `D' to indicate destruction. */ function_key = constructor_p ? 'I' : 'D'; /* We emit the function lazily, to avoid generating empty global constructors and destructors. */ body = NULL_TREE; /* Call the static storage duration function with appropriate arguments. */ if (ssdf_decls) for (i = 0; i < ssdf_decls->elements_used; ++i) { fndecl = VARRAY_TREE (ssdf_decls, i); /* Calls to pure or const functions will expand to nothing. */ if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE))) { if (! body) body = start_objects (function_key, priority); arguments = tree_cons (NULL_TREE, build_int_cst (NULL_TREE, priority), NULL_TREE); arguments = tree_cons (NULL_TREE, build_int_cst (NULL_TREE, constructor_p), arguments); finish_expr_stmt (build_function_call (fndecl, arguments)); } } /* If we're generating code for the DEFAULT_INIT_PRIORITY, throw in calls to any functions marked with attributes indicating that they should be called at initialization- or destruction-time. */ if (priority == DEFAULT_INIT_PRIORITY) { tree fns; for (fns = constructor_p ? static_ctors : static_dtors; fns; fns = TREE_CHAIN (fns)) { fndecl = TREE_VALUE (fns); /* Calls to pure/const functions will expand to nothing. */ if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE))) { if (! body) body = start_objects (function_key, priority); finish_expr_stmt (build_function_call (fndecl, NULL_TREE)); } } } /* Close out the function. */ if (body) finish_objects (function_key, priority, body); } /* Generate constructor and destructor functions for the priority indicated by N. */ static int generate_ctor_and_dtor_functions_for_priority (splay_tree_node n, void * data) { location_t *locus = data; int priority = (int) n->key; priority_info pi = (priority_info) n->value; /* Generate the functions themselves, but only if they are really needed. */ if (pi->initializations_p || (priority == DEFAULT_INIT_PRIORITY && static_ctors)) generate_ctor_or_dtor_function (/*constructor_p=*/true, priority, locus); if (pi->destructions_p || (priority == DEFAULT_INIT_PRIORITY && static_dtors)) generate_ctor_or_dtor_function (/*constructor_p=*/false, priority, locus); /* Keep iterating. */ return 0; } /* Called via LANGHOOK_CALLGRAPH_ANALYZE_EXPR. It is supposed to mark decls referenced from frontend specific constructs; it will be called only for language-specific tree nodes. Here we must deal with member pointers. */ tree cxx_callgraph_analyze_expr (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED, tree from ATTRIBUTE_UNUSED) { tree t = *tp; switch (TREE_CODE (t)) { case PTRMEM_CST: if (TYPE_PTRMEMFUNC_P (TREE_TYPE (t))) cgraph_mark_needed_node (cgraph_node (PTRMEM_CST_MEMBER (t))); break; case BASELINK: if (TREE_CODE (BASELINK_FUNCTIONS (t)) == FUNCTION_DECL) cgraph_mark_needed_node (cgraph_node (BASELINK_FUNCTIONS (t))); break; case VAR_DECL: if (DECL_VTABLE_OR_VTT_P (t)) { /* The ABI requires that all virtual tables be emitted whenever one of them is. */ tree vtbl; for (vtbl = CLASSTYPE_VTABLES (DECL_CONTEXT (t)); vtbl; vtbl = TREE_CHAIN (vtbl)) mark_decl_referenced (vtbl); } else if (DECL_CONTEXT (t) && TREE_CODE (DECL_CONTEXT (t)) == FUNCTION_DECL) /* If we need a static variable in a function, then we need the containing function. */ mark_decl_referenced (DECL_CONTEXT (t)); break; default: break; } return NULL; } /* This routine is called from the last rule in yyparse (). Its job is to create all the code needed to initialize and destroy the global aggregates. We do the destruction first, since that way we only need to reverse the decls once. */ void cp_finish_file (void) { tree vars; bool reconsider; size_t i; location_t locus; unsigned ssdf_count = 0; int retries = 0; locus = input_location; at_eof = 1; /* Bad parse errors. Just forget about it. */ if (! global_bindings_p () || current_class_type || decl_namespace_list) return; if (pch_file) c_common_write_pch (); #ifdef USE_MAPPED_LOCATION /* FIXME - huh? */ #else /* Otherwise, GDB can get confused, because in only knows about source for LINENO-1 lines. */ input_line -= 1; #endif /* We now have to write out all the stuff we put off writing out. These include: o Template specializations that we have not yet instantiated, but which are needed. o Initialization and destruction for non-local objects with static storage duration. (Local objects with static storage duration are initialized when their scope is first entered, and are cleaned up via atexit.) o Virtual function tables. All of these may cause others to be needed. For example, instantiating one function may cause another to be needed, and generating the initializer for an object may cause templates to be instantiated, etc., etc. */ timevar_push (TV_VARCONST); emit_support_tinfos (); do { tree t; reconsider = false; /* If there are templates that we've put off instantiating, do them now. */ instantiate_pending_templates (retries); ggc_collect (); /* Write out virtual tables as required. Note that writing out the virtual table for a template class may cause the instantiation of members of that class. If we write out vtables then we remove the class from our list so we don't have to look at it again. */ while (keyed_classes != NULL_TREE && maybe_emit_vtables (TREE_VALUE (keyed_classes))) { reconsider = true; keyed_classes = TREE_CHAIN (keyed_classes); } t = keyed_classes; if (t != NULL_TREE) { tree next = TREE_CHAIN (t); while (next) { if (maybe_emit_vtables (TREE_VALUE (next))) { reconsider = true; TREE_CHAIN (t) = TREE_CHAIN (next); } else t = next; next = TREE_CHAIN (t); } } /* Write out needed type info variables. We have to be careful looping through unemitted decls, because emit_tinfo_decl may cause other variables to be needed. New elements will be appended, and we remove from the vector those that actually get emitted. */ for (i = VEC_length (tree, unemitted_tinfo_decls); VEC_iterate (tree, unemitted_tinfo_decls, --i, t);) if (emit_tinfo_decl (t)) { reconsider = true; VEC_unordered_remove (tree, unemitted_tinfo_decls, i); } /* The list of objects with static storage duration is built up in reverse order. We clear STATIC_AGGREGATES so that any new aggregates added during the initialization of these will be initialized in the correct order when we next come around the loop. */ vars = prune_vars_needing_no_initialization (&static_aggregates); if (vars) { tree v; /* We need to start a new initialization function each time through the loop. That's because we need to know which vtables have been referenced, and TREE_SYMBOL_REFERENCED isn't computed until a function is finished, and written out. That's a deficiency in the back-end. When this is fixed, these initialization functions could all become inline, with resulting performance improvements. */ tree ssdf_body; /* Set the line and file, so that it is obviously not from the source file. */ input_location = locus; ssdf_body = start_static_storage_duration_function (ssdf_count); /* Make sure the back end knows about all the variables. */ write_out_vars (vars); /* First generate code to do all the initializations. */ for (v = vars; v; v = TREE_CHAIN (v)) do_static_initialization (TREE_VALUE (v), TREE_PURPOSE (v)); /* Then, generate code to do all the destructions. Do these in reverse order so that the most recently constructed variable is the first destroyed. If we're using __cxa_atexit, then we don't need to do this; functions were registered at initialization time to destroy the local statics. */ if (!flag_use_cxa_atexit) { vars = nreverse (vars); for (v = vars; v; v = TREE_CHAIN (v)) do_static_destruction (TREE_VALUE (v)); } else vars = NULL_TREE; /* Finish up the static storage duration function for this round. */ input_location = locus; finish_static_storage_duration_function (ssdf_body); /* All those initializations and finalizations might cause us to need more inline functions, more template instantiations, etc. */ reconsider = true; ssdf_count++; #ifdef USE_MAPPED_LOCATION /* ??? */ #else locus.line++; #endif } /* Go through the set of inline functions whose bodies have not been emitted yet. If out-of-line copies of these functions are required, emit them. */ for (i = 0; i < deferred_fns_used; ++i) { tree decl = VARRAY_TREE (deferred_fns, i); /* Does it need synthesizing? */ if (DECL_ARTIFICIAL (decl) && ! DECL_INITIAL (decl) && (! DECL_REALLY_EXTERN (decl) || DECL_INLINE (decl))) { /* Even though we're already at the top-level, we push there again. That way, when we pop back a few lines hence, all of our state is restored. Otherwise, finish_function doesn't clean things up, and we end up with CURRENT_FUNCTION_DECL set. */ push_to_top_level (); synthesize_method (decl); pop_from_top_level (); reconsider = true; } if (!DECL_SAVED_TREE (decl)) continue; import_export_decl (decl); /* We lie to the back-end, pretending that some functions are not defined when they really are. This keeps these functions from being put out unnecessarily. But, we must stop lying when the functions are referenced, or if they are not comdat since they need to be put out now. This is done in a separate for cycle, because if some deferred function is contained in another deferred function later in deferred_fns varray, rest_of_compilation would skip this function and we really cannot expand the same function twice. */ if (DECL_NOT_REALLY_EXTERN (decl) && DECL_INITIAL (decl) && decl_needed_p (decl)) DECL_EXTERNAL (decl) = 0; /* If we're going to need to write this function out, and there's already a body for it, create RTL for it now. (There might be no body if this is a method we haven't gotten around to synthesizing yet.) */ if (!DECL_EXTERNAL (decl) && decl_needed_p (decl) && !TREE_ASM_WRITTEN (decl) && !cgraph_node (decl)->local.finalized) { /* We will output the function; no longer consider it in this loop. */ DECL_DEFER_OUTPUT (decl) = 0; /* Generate RTL for this function now that we know we need it. */ expand_or_defer_fn (decl); /* If we're compiling -fsyntax-only pretend that this function has been written out so that we don't try to expand it again. */ if (flag_syntax_only) TREE_ASM_WRITTEN (decl) = 1; reconsider = true; } } if (walk_namespaces (wrapup_globals_for_namespace, /*data=*/0)) reconsider = true; /* Static data members are just like namespace-scope globals. */ for (i = 0; i < pending_statics_used; ++i) { tree decl = VARRAY_TREE (pending_statics, i); if (var_finalized_p (decl) || DECL_REALLY_EXTERN (decl)) continue; import_export_decl (decl); /* If this static data member is needed, provide it to the back end. */ if (DECL_NOT_REALLY_EXTERN (decl) && decl_needed_p (decl)) DECL_EXTERNAL (decl) = 0; } if (pending_statics && wrapup_global_declarations (&VARRAY_TREE (pending_statics, 0), pending_statics_used)) reconsider = true; /* Ask the back end to emit functions and variables that are enqueued. These emissions may result in marking more entities as needed. */ if (cgraph_assemble_pending_functions ()) reconsider = true; if (cgraph_varpool_assemble_pending_decls ()) reconsider = true; retries++; } while (reconsider); /* All used inline functions must have a definition at this point. */ for (i = 0; i < deferred_fns_used; ++i) { tree decl = VARRAY_TREE (deferred_fns, i); if (/* Check online inline functions that were actually used. */ TREE_USED (decl) && DECL_DECLARED_INLINE_P (decl) /* But not defined. */ && DECL_REALLY_EXTERN (decl) /* If we decided to emit this function in another translation unit, the fact that the definition was missing here likely indicates only that the repository decided to place the function elsewhere. With -Winline, we will still warn if we could not inline the function. */ && !flag_use_repository /* An explicit instantiation can be used to specify that the body is in another unit. It will have already verified there was a definition. */ && !DECL_EXPLICIT_INSTANTIATION (decl)) { cp_warning_at ("inline function %qD used but never defined", decl); /* This symbol is effectively an "extern" declaration now. This is not strictly necessary, but removes a duplicate warning. */ TREE_PUBLIC (decl) = 1; } } /* We give C linkage to static constructors and destructors. */ push_lang_context (lang_name_c); /* Generate initialization and destruction functions for all priorities for which they are required. */ if (priority_info_map) splay_tree_foreach (priority_info_map, generate_ctor_and_dtor_functions_for_priority, /*data=*/&locus); else { if (static_ctors) generate_ctor_or_dtor_function (/*constructor_p=*/true, DEFAULT_INIT_PRIORITY, &locus); if (static_dtors) generate_ctor_or_dtor_function (/*constructor_p=*/false, DEFAULT_INIT_PRIORITY, &locus); } /* We're done with the splay-tree now. */ if (priority_info_map) splay_tree_delete (priority_info_map); /* Generate any missing aliases. */ maybe_apply_pending_pragma_weaks (); /* We're done with static constructors, so we can go back to "C++" linkage now. */ pop_lang_context (); cgraph_finalize_compilation_unit (); cgraph_optimize (); /* Now, issue warnings about static, but not defined, functions, etc., and emit debugging information. */ walk_namespaces (wrapup_globals_for_namespace, /*data=*/&reconsider); if (pending_statics) check_global_declarations (&VARRAY_TREE (pending_statics, 0), pending_statics_used); finish_repo (); /* The entire file is now complete. If requested, dump everything to a file. */ { int flags; FILE *stream = dump_begin (TDI_tu, &flags); if (stream) { dump_node (global_namespace, flags & ~TDF_SLIM, stream); dump_end (TDI_tu, stream); } } timevar_pop (TV_VARCONST); if (flag_detailed_statistics) { dump_tree_statistics (); dump_time_statistics (); } input_location = locus; #ifdef ENABLE_CHECKING validate_conversion_obstack (); #endif /* ENABLE_CHECKING */ } /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the function to call in parse-tree form; it has not yet been semantically analyzed. ARGS are the arguments to the function. They have already been semantically analyzed. */ tree build_offset_ref_call_from_tree (tree fn, tree args) { tree orig_fn; tree orig_args; tree expr; tree object; orig_fn = fn; orig_args = args; object = TREE_OPERAND (fn, 0); if (processing_template_decl) { gcc_assert (TREE_CODE (fn) == DOTSTAR_EXPR || TREE_CODE (fn) == MEMBER_REF); if (type_dependent_expression_p (fn) || any_type_dependent_arguments_p (args)) return build_min_nt (CALL_EXPR, fn, args, NULL_TREE); /* Transform the arguments and add the implicit "this" parameter. That must be done before the FN is transformed because we depend on the form of FN. */ args = build_non_dependent_args (args); if (TREE_CODE (fn) == DOTSTAR_EXPR) object = build_unary_op (ADDR_EXPR, object, 0); object = build_non_dependent_expr (object); args = tree_cons (NULL_TREE, object, args); /* Now that the arguments are done, transform FN. */ fn = build_non_dependent_expr (fn); } /* A qualified name corresponding to a bound pointer-to-member is represented as an OFFSET_REF: struct B { void g(); }; void (B::*p)(); void B::g() { (this->*p)(); } */ if (TREE_CODE (fn) == OFFSET_REF) { tree object_addr = build_unary_op (ADDR_EXPR, object, 0); fn = TREE_OPERAND (fn, 1); fn = get_member_function_from_ptrfunc (&object_addr, fn); args = tree_cons (NULL_TREE, object_addr, args); } expr = build_function_call (fn, args); if (processing_template_decl && expr != error_mark_node) return build_min_non_dep (CALL_EXPR, expr, orig_fn, orig_args, NULL_TREE); return expr; } void check_default_args (tree x) { tree arg = TYPE_ARG_TYPES (TREE_TYPE (x)); bool saw_def = false; int i = 0 - (TREE_CODE (TREE_TYPE (x)) == METHOD_TYPE); for (; arg && arg != void_list_node; arg = TREE_CHAIN (arg), ++i) { if (TREE_PURPOSE (arg)) saw_def = true; else if (saw_def) { cp_error_at ("default argument missing for parameter %P of %q+#D", i, x); break; } } } void mark_used (tree decl) { TREE_USED (decl) = 1; if (processing_template_decl || skip_evaluation) return; if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl) && !TREE_ASM_WRITTEN (decl)) /* Remember it, so we can check it was defined. */ { if (DECL_DEFERRED_FN (decl)) return; note_vague_linkage_fn (decl); } assemble_external (decl); /* Is it a synthesized method that needs to be synthesized? */ if (TREE_CODE (decl) == FUNCTION_DECL && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl) && DECL_ARTIFICIAL (decl) && !DECL_THUNK_P (decl) && ! DECL_INITIAL (decl) /* Kludge: don't synthesize for default args. Unfortunately this rules out initializers of namespace-scoped objects too, but it's sort-of ok if the implicit ctor or dtor decl keeps pointing to the class location. */ && current_function_decl) { /* Put the function definition at the position where it is needed, rather than within the body of the class. That way, an error during the generation of the implicit body points at the place where the attempt to generate the function occurs, giving the user a hint as to why we are attempting to generate the function. */ DECL_SOURCE_LOCATION (decl) = input_location; synthesize_method (decl); /* If we've already synthesized the method we don't need to instantiate it, so we can return right away. */ return; } /* If this is a function or variable that is an instance of some template, we now know that we will need to actually do the instantiation. We check that DECL is not an explicit instantiation because that is not checked in instantiate_decl. */ if ((DECL_NON_THUNK_FUNCTION_P (decl) || TREE_CODE (decl) == VAR_DECL) && DECL_LANG_SPECIFIC (decl) && DECL_TEMPLATE_INFO (decl) && (!DECL_EXPLICIT_INSTANTIATION (decl) || (TREE_CODE (decl) == FUNCTION_DECL && DECL_INLINE (DECL_TEMPLATE_RESULT (template_for_substitution (decl)))))) /* We put off instantiating functions in order to improve compile times. Maintaining a stack of active functions is expensive, and the inliner knows to instantiate any functions it might need. */ instantiate_decl (decl, /*defer_ok=*/true, /*undefined_ok=*/0); } #include "gt-cp-decl2.h"