1 /* Report error messages, build initializers, and perform
2 some front-end optimizations for C++ compiler.
3 Copyright (C) 1987-2015 Free Software Foundation, Inc.
4 Hacked by Michael Tiemann (tiemann@cygnus.com)
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
23 /* This file is part of the C++ front end.
24 It contains routines to build C++ expressions given their operands,
25 including computing the types of the result, C and C++ specific error
26 checks, and some optimization. */
30 #include "coretypes.h"
35 #include "double-int.h"
42 #include "stor-layout.h"
47 #include "diagnostic-core.h"
51 process_init_constructor (tree type, tree init, tsubst_flags_t complain);
54 /* Print an error message stemming from an attempt to use
55 BASETYPE as a base class for TYPE. */
58 error_not_base_type (tree basetype, tree type)
60 if (TREE_CODE (basetype) == FUNCTION_DECL)
61 basetype = DECL_CONTEXT (basetype);
62 error ("type %qT is not a base type for type %qT", basetype, type);
63 return error_mark_node;
67 binfo_or_else (tree base, tree type)
69 tree binfo = lookup_base (type, base, ba_unique,
70 NULL, tf_warning_or_error);
72 if (binfo == error_mark_node)
75 error_not_base_type (base, type);
79 /* According to ARM $7.1.6, "A `const' object may be initialized, but its
80 value may not be changed thereafter. */
83 cxx_readonly_error (tree arg, enum lvalue_use errstring)
86 /* This macro is used to emit diagnostics to ensure that all format
87 strings are complete sentences, visible to gettext and checked at
90 #define ERROR_FOR_ASSIGNMENT(AS, ASM, IN, DE, ARG) \
107 gcc_unreachable (); \
111 /* Handle C++-specific things first. */
114 && DECL_LANG_SPECIFIC (arg)
115 && DECL_IN_AGGR_P (arg)
116 && !TREE_STATIC (arg))
117 ERROR_FOR_ASSIGNMENT (G_("assignment of "
118 "constant field %qD"),
119 G_("constant field %qD "
120 "used as %<asm%> output"),
122 "constant field %qD"),
124 "constant field %qD"),
126 else if (INDIRECT_REF_P (arg)
127 && TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0))) == REFERENCE_TYPE
128 && (VAR_P (TREE_OPERAND (arg, 0))
129 || TREE_CODE (TREE_OPERAND (arg, 0)) == PARM_DECL))
130 ERROR_FOR_ASSIGNMENT (G_("assignment of "
131 "read-only reference %qD"),
132 G_("read-only reference %qD "
133 "used as %<asm%> output"),
135 "read-only reference %qD"),
137 "read-only reference %qD"),
138 TREE_OPERAND (arg, 0));
140 readonly_error (input_location, arg, errstring);
144 /* Structure that holds information about declarations whose type was
145 incomplete and we could not check whether it was abstract or not. */
147 struct GTY((chain_next ("%h.next"), for_user)) pending_abstract_type {
148 /* Declaration which we are checking for abstractness. It is either
149 a DECL node, or an IDENTIFIER_NODE if we do not have a full
150 declaration available. */
153 /* Type which will be checked for abstractness. */
156 /* Kind of use in an unnamed declarator. */
157 abstract_class_use use;
159 /* Position of the declaration. This is only needed for IDENTIFIER_NODEs,
160 because DECLs already carry locus information. */
163 /* Link to the next element in list. */
164 struct pending_abstract_type* next;
167 struct abstract_type_hasher : ggc_hasher<pending_abstract_type *>
169 typedef tree compare_type;
170 static hashval_t hash (pending_abstract_type *);
171 static bool equal (pending_abstract_type *, tree);
174 /* Compute the hash value of the node VAL. This function is used by the
175 hash table abstract_pending_vars. */
178 abstract_type_hasher::hash (pending_abstract_type *pat)
180 return (hashval_t) TYPE_UID (pat->type);
184 /* Compare node VAL1 with the type VAL2. This function is used by the
185 hash table abstract_pending_vars. */
188 abstract_type_hasher::equal (pending_abstract_type *pat1, tree type2)
190 return (pat1->type == type2);
193 /* Hash table that maintains pending_abstract_type nodes, for which we still
194 need to check for type abstractness. The key of the table is the type
195 of the declaration. */
196 static GTY (()) hash_table<abstract_type_hasher> *abstract_pending_vars = NULL;
198 static int abstract_virtuals_error_sfinae (tree, tree, abstract_class_use, tsubst_flags_t);
200 /* This function is called after TYPE is completed, and will check if there
201 are pending declarations for which we still need to verify the abstractness
202 of TYPE, and emit a diagnostic (through abstract_virtuals_error) if TYPE
203 turned out to be incomplete. */
206 complete_type_check_abstract (tree type)
208 struct pending_abstract_type *pat;
209 location_t cur_loc = input_location;
211 gcc_assert (COMPLETE_TYPE_P (type));
213 if (!abstract_pending_vars)
216 /* Retrieve the list of pending declarations for this type. */
217 pending_abstract_type **slot
218 = abstract_pending_vars->find_slot_with_hash (type, TYPE_UID (type),
225 /* If the type is not abstract, do not do anything. */
226 if (CLASSTYPE_PURE_VIRTUALS (type))
228 struct pending_abstract_type *prev = 0, *next;
230 /* Reverse the list to emit the errors in top-down order. */
231 for (; pat; pat = next)
239 /* Go through the list, and call abstract_virtuals_error for each
240 element: it will issue a diagnostic if the type is abstract. */
243 gcc_assert (type == pat->type);
245 /* Tweak input_location so that the diagnostic appears at the correct
246 location. Notice that this is only needed if the decl is an
248 input_location = pat->locus;
249 abstract_virtuals_error_sfinae (pat->decl, pat->type, pat->use,
250 tf_warning_or_error);
255 abstract_pending_vars->clear_slot (slot);
257 input_location = cur_loc;
261 /* If TYPE has abstract virtual functions, issue an error about trying
262 to create an object of that type. DECL is the object declared, or
263 NULL_TREE if the declaration is unavailable, in which case USE specifies
264 the kind of invalid use. Returns 1 if an error occurred; zero if
268 abstract_virtuals_error_sfinae (tree decl, tree type, abstract_class_use use,
269 tsubst_flags_t complain)
271 vec<tree, va_gc> *pure;
273 /* This function applies only to classes. Any other entity can never
275 if (!CLASS_TYPE_P (type))
277 type = TYPE_MAIN_VARIANT (type);
280 /* Instantiation here seems to be required by the standard,
281 but breaks e.g. boost::bind. FIXME! */
282 /* In SFINAE, non-N3276 context, force instantiation. */
283 if (!(complain & (tf_error|tf_decltype)))
284 complete_type (type);
287 /* If the type is incomplete, we register it within a hash table,
288 so that we can check again once it is completed. This makes sense
289 only for objects for which we have a declaration or at least a
291 if (!COMPLETE_TYPE_P (type) && (complain & tf_error))
293 struct pending_abstract_type *pat;
295 gcc_assert (!decl || DECL_P (decl) || identifier_p (decl));
297 if (!abstract_pending_vars)
298 abstract_pending_vars
299 = hash_table<abstract_type_hasher>::create_ggc (31);
301 pending_abstract_type **slot
302 = abstract_pending_vars->find_slot_with_hash (type, TYPE_UID (type),
305 pat = ggc_alloc<pending_abstract_type> ();
309 pat->locus = ((decl && DECL_P (decl))
310 ? DECL_SOURCE_LOCATION (decl)
319 if (!TYPE_SIZE (type))
320 /* TYPE is being defined, and during that time
321 CLASSTYPE_PURE_VIRTUALS holds the inline friends. */
324 pure = CLASSTYPE_PURE_VIRTUALS (type);
328 if (!(complain & tf_error))
334 error ("cannot declare variable %q+D to be of abstract "
335 "type %qT", decl, type);
336 else if (TREE_CODE (decl) == PARM_DECL)
338 if (DECL_NAME (decl))
339 error ("cannot declare parameter %q+D to be of abstract type %qT",
342 error ("cannot declare parameter to be of abstract type %qT",
345 else if (TREE_CODE (decl) == FIELD_DECL)
346 error ("cannot declare field %q+D to be of abstract type %qT",
348 else if (TREE_CODE (decl) == FUNCTION_DECL
349 && TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE)
350 error ("invalid abstract return type for member function %q+#D", decl);
351 else if (TREE_CODE (decl) == FUNCTION_DECL)
352 error ("invalid abstract return type for function %q+#D", decl);
353 else if (identifier_p (decl))
354 /* Here we do not have location information. */
355 error ("invalid abstract type %qT for %qE", type, decl);
357 error ("invalid abstract type for %q+D", decl);
362 error ("creating array of %qT, which is an abstract class type", type);
365 error ("invalid cast to abstract class type %qT", type);
368 error ("invalid new-expression of abstract class type %qT", type);
371 error ("invalid abstract return type %qT", type);
374 error ("invalid abstract parameter type %qT", type);
377 error ("expression of abstract class type %qT cannot "
378 "be used in throw-expression", type);
381 error ("cannot declare catch parameter to be of abstract "
382 "class type %qT", type);
385 error ("cannot allocate an object of abstract type %qT", type);
388 /* Only go through this once. */
394 inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (type)),
395 " because the following virtual functions are pure within %qT:",
398 FOR_EACH_VEC_ELT (*pure, ix, fn)
399 if (! DECL_CLONED_FUNCTION_P (fn)
400 || DECL_COMPLETE_DESTRUCTOR_P (fn))
401 inform (input_location, "\t%+#D", fn);
403 /* Now truncate the vector. This leaves it non-null, so we know
404 there are pure virtuals, but empty so we don't list them out
413 abstract_virtuals_error_sfinae (tree decl, tree type, tsubst_flags_t complain)
415 return abstract_virtuals_error_sfinae (decl, type, ACU_UNKNOWN, complain);
419 abstract_virtuals_error_sfinae (abstract_class_use use, tree type,
420 tsubst_flags_t complain)
422 return abstract_virtuals_error_sfinae (NULL_TREE, type, use, complain);
426 /* Wrapper for the above function in the common case of wanting errors. */
429 abstract_virtuals_error (tree decl, tree type)
431 return abstract_virtuals_error_sfinae (decl, type, tf_warning_or_error);
435 abstract_virtuals_error (abstract_class_use use, tree type)
437 return abstract_virtuals_error_sfinae (use, type, tf_warning_or_error);
440 /* Print an inform about the declaration of the incomplete type TYPE. */
443 cxx_incomplete_type_inform (const_tree type)
445 if (!TYPE_MAIN_DECL (type))
448 location_t loc = DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (type));
449 tree ptype = strip_top_quals (CONST_CAST_TREE (type));
451 if (current_class_type
452 && TYPE_BEING_DEFINED (current_class_type)
453 && same_type_p (ptype, current_class_type))
454 inform (loc, "definition of %q#T is not complete until "
455 "the closing brace", ptype);
456 else if (!TYPE_TEMPLATE_INFO (ptype))
457 inform (loc, "forward declaration of %q#T", ptype);
459 inform (loc, "declaration of %q#T", ptype);
462 /* Print an error message for invalid use of an incomplete type.
463 VALUE is the expression that was used (or 0 if that isn't known)
464 and TYPE is the type that was invalid. DIAG_KIND indicates the
465 type of diagnostic (see diagnostic.def). */
468 cxx_incomplete_type_diagnostic (const_tree value, const_tree type,
469 diagnostic_t diag_kind)
471 bool is_decl = false, complained = false;
473 gcc_assert (diag_kind == DK_WARNING
474 || diag_kind == DK_PEDWARN
475 || diag_kind == DK_ERROR);
477 /* Avoid duplicate error message. */
478 if (TREE_CODE (type) == ERROR_MARK)
481 if (value != 0 && (VAR_P (value)
482 || TREE_CODE (value) == PARM_DECL
483 || TREE_CODE (value) == FIELD_DECL))
485 complained = emit_diagnostic (diag_kind, input_location, 0,
486 "%q+D has incomplete type", value);
490 /* We must print an error message. Be clever about what it says. */
492 switch (TREE_CODE (type))
498 complained = emit_diagnostic (diag_kind, input_location, 0,
499 "invalid use of incomplete type %q#T",
502 cxx_incomplete_type_inform (type);
506 emit_diagnostic (diag_kind, input_location, 0,
507 "invalid use of %qT", type);
511 if (TYPE_DOMAIN (type))
513 type = TREE_TYPE (type);
516 emit_diagnostic (diag_kind, input_location, 0,
517 "invalid use of array with unspecified bounds");
523 tree member = TREE_OPERAND (value, 1);
524 if (is_overloaded_fn (member))
525 member = get_first_fn (member);
526 if (DECL_FUNCTION_MEMBER_P (member)
527 && ! flag_ms_extensions)
528 emit_diagnostic (diag_kind, input_location, 0,
529 "invalid use of member function "
530 "(did you forget the %<()%> ?)");
532 emit_diagnostic (diag_kind, input_location, 0,
533 "invalid use of member "
534 "(did you forget the %<&%> ?)");
538 case TEMPLATE_TYPE_PARM:
540 emit_diagnostic (diag_kind, input_location, 0,
541 "invalid use of %<auto%>");
543 emit_diagnostic (diag_kind, input_location, 0,
544 "invalid use of template type parameter %qT", type);
547 case BOUND_TEMPLATE_TEMPLATE_PARM:
548 emit_diagnostic (diag_kind, input_location, 0,
549 "invalid use of template template parameter %qT",
554 emit_diagnostic (diag_kind, input_location, 0,
555 "invalid use of dependent type %qT", type);
559 if (type == init_list_type_node)
561 emit_diagnostic (diag_kind, input_location, 0,
562 "invalid use of brace-enclosed initializer list");
565 gcc_assert (type == unknown_type_node);
566 if (value && TREE_CODE (value) == COMPONENT_REF)
568 else if (value && TREE_CODE (value) == ADDR_EXPR)
569 emit_diagnostic (diag_kind, input_location, 0,
570 "address of overloaded function with no contextual "
572 else if (value && TREE_CODE (value) == OVERLOAD)
573 emit_diagnostic (diag_kind, input_location, 0,
574 "overloaded function with no contextual type information");
576 emit_diagnostic (diag_kind, input_location, 0,
577 "insufficient contextual information to determine type");
585 /* Backward-compatibility interface to incomplete_type_diagnostic;
586 required by ../tree.c. */
587 #undef cxx_incomplete_type_error
589 cxx_incomplete_type_error (const_tree value, const_tree type)
591 cxx_incomplete_type_diagnostic (value, type, DK_ERROR);
595 /* The recursive part of split_nonconstant_init. DEST is an lvalue
596 expression to which INIT should be assigned. INIT is a CONSTRUCTOR.
597 Return true if the whole of the value was initialized by the
598 generated statements. */
601 split_nonconstant_init_1 (tree dest, tree init)
603 unsigned HOST_WIDE_INT idx;
604 tree field_index, value;
605 tree type = TREE_TYPE (dest);
606 tree inner_type = NULL;
607 bool array_type_p = false;
608 bool complete_p = true;
609 HOST_WIDE_INT num_split_elts = 0;
611 switch (TREE_CODE (type))
614 inner_type = TREE_TYPE (type);
616 if ((TREE_SIDE_EFFECTS (init)
617 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
618 || array_of_runtime_bound_p (type))
620 /* For an array, we only need/want a single cleanup region rather
621 than one per element. */
622 tree code = build_vec_init (dest, NULL_TREE, init, false, 1,
623 tf_warning_or_error);
631 case QUAL_UNION_TYPE:
632 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx,
635 /* The current implementation of this algorithm assumes that
636 the field was set for all the elements. This is usually done
637 by process_init_constructor. */
638 gcc_assert (field_index);
641 inner_type = TREE_TYPE (field_index);
643 if (TREE_CODE (value) == CONSTRUCTOR)
648 sub = build4 (ARRAY_REF, inner_type, dest, field_index,
649 NULL_TREE, NULL_TREE);
651 sub = build3 (COMPONENT_REF, inner_type, dest, field_index,
654 if (!split_nonconstant_init_1 (sub, value))
657 CONSTRUCTOR_ELTS (init)->ordered_remove (idx--);
660 else if (!initializer_constant_valid_p (value, inner_type))
665 /* FIXME: Ordered removal is O(1) so the whole function is
666 worst-case quadratic. This could be fixed using an aside
667 bitmap to record which elements must be removed and remove
668 them all at the same time. Or by merging
669 split_non_constant_init into process_init_constructor_array,
670 that is separating constants from non-constants while building
672 CONSTRUCTOR_ELTS (init)->ordered_remove (idx);
675 if (TREE_CODE (field_index) == RANGE_EXPR)
677 /* Use build_vec_init to initialize a range. */
678 tree low = TREE_OPERAND (field_index, 0);
679 tree hi = TREE_OPERAND (field_index, 1);
680 sub = build4 (ARRAY_REF, inner_type, dest, low,
681 NULL_TREE, NULL_TREE);
682 sub = cp_build_addr_expr (sub, tf_warning_or_error);
683 tree max = size_binop (MINUS_EXPR, hi, low);
684 code = build_vec_init (sub, max, value, false, 0,
685 tf_warning_or_error);
687 if (tree_fits_shwi_p (max))
688 num_split_elts += tree_to_shwi (max);
693 sub = build4 (ARRAY_REF, inner_type, dest, field_index,
694 NULL_TREE, NULL_TREE);
696 sub = build3 (COMPONENT_REF, inner_type, dest, field_index,
699 code = build2 (INIT_EXPR, inner_type, sub, value);
700 code = build_stmt (input_location, EXPR_STMT, code);
701 code = maybe_cleanup_point_expr_void (code);
703 if (type_build_dtor_call (inner_type))
705 code = (build_special_member_call
706 (sub, complete_dtor_identifier, NULL, inner_type,
707 LOOKUP_NORMAL, tf_warning_or_error));
708 if (!TYPE_HAS_TRIVIAL_DESTRUCTOR (inner_type))
709 finish_eh_cleanup (code);
719 if (!initializer_constant_valid_p (init, type))
722 tree cons = copy_node (init);
723 CONSTRUCTOR_ELTS (init) = NULL;
724 code = build2 (MODIFY_EXPR, type, dest, cons);
725 code = build_stmt (input_location, EXPR_STMT, code);
727 num_split_elts += CONSTRUCTOR_NELTS (init);
735 /* The rest of the initializer is now a constant. */
736 TREE_CONSTANT (init) = 1;
737 return complete_p && complete_ctor_at_level_p (TREE_TYPE (init),
738 num_split_elts, inner_type);
741 /* A subroutine of store_init_value. Splits non-constant static
742 initializer INIT into a constant part and generates code to
743 perform the non-constant part of the initialization to DEST.
744 Returns the code for the runtime init. */
747 split_nonconstant_init (tree dest, tree init)
751 if (TREE_CODE (init) == TARGET_EXPR)
752 init = TARGET_EXPR_INITIAL (init);
753 if (TREE_CODE (init) == CONSTRUCTOR)
755 code = push_stmt_list ();
756 if (split_nonconstant_init_1 (dest, init))
758 code = pop_stmt_list (code);
759 DECL_INITIAL (dest) = init;
760 TREE_READONLY (dest) = 0;
763 code = build2 (INIT_EXPR, TREE_TYPE (dest), dest, init);
768 /* Perform appropriate conversions on the initial value of a variable,
769 store it in the declaration DECL,
770 and print any error messages that are appropriate.
771 If the init is invalid, store an ERROR_MARK.
773 C++: Note that INIT might be a TREE_LIST, which would mean that it is
774 a base class initializer for some aggregate type, hopefully compatible
775 with DECL. If INIT is a single element, and DECL is an aggregate
776 type, we silently convert INIT into a TREE_LIST, allowing a constructor
779 If INIT is a TREE_LIST and there is no constructor, turn INIT
780 into a CONSTRUCTOR and use standard initialization techniques.
781 Perhaps a warning should be generated?
783 Returns code to be executed if initialization could not be performed
784 for static variable. In that case, caller must emit the code. */
787 store_init_value (tree decl, tree init, vec<tree, va_gc>** cleanups, int flags)
791 /* If variable's type was invalidly declared, just ignore it. */
793 type = TREE_TYPE (decl);
794 if (TREE_CODE (type) == ERROR_MARK)
797 if (MAYBE_CLASS_TYPE_P (type))
799 if (TREE_CODE (init) == TREE_LIST)
801 error ("constructor syntax used, but no constructor declared "
802 "for type %qT", type);
803 init = build_constructor_from_list (init_list_type_node, nreverse (init));
807 /* End of special C++ code. */
809 if (flags & LOOKUP_ALREADY_DIGESTED)
812 /* Digest the specified initializer into an expression. */
813 value = digest_init_flags (type, init, flags);
815 value = extend_ref_init_temps (decl, value, cleanups);
817 /* In C++11 constant expression is a semantic, not syntactic, property.
818 In C++98, make sure that what we thought was a constant expression at
819 template definition time is still constant and otherwise perform this
820 as optimization, e.g. to fold SIZEOF_EXPRs in the initializer. */
821 if (decl_maybe_constant_var_p (decl) || TREE_STATIC (decl))
824 value = instantiate_non_dependent_expr (value);
825 if (DECL_DECLARED_CONSTEXPR_P (decl)
826 || DECL_IN_AGGR_P (decl))
828 /* Diagnose a non-constant initializer for constexpr. */
829 if (processing_template_decl
830 && !require_potential_constant_expression (value))
831 value = error_mark_node;
833 value = cxx_constant_value (value, decl);
835 value = maybe_constant_init (value, decl);
836 if (TREE_CODE (value) == CONSTRUCTOR && cp_has_mutable_p (type))
837 /* Poison this CONSTRUCTOR so it can't be copied to another
838 constexpr variable. */
839 CONSTRUCTOR_MUTABLE_POISON (value) = true;
840 const_init = (reduced_constant_expression_p (value)
841 || error_operand_p (value));
842 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = const_init;
843 TREE_CONSTANT (decl) = const_init && decl_maybe_constant_var_p (decl);
846 if (cxx_dialect >= cxx14)
847 /* Handle aggregate NSDMI in non-constant initializers, too. */
848 value = replace_placeholders (value, decl);
850 /* If the initializer is not a constant, fill in DECL_INITIAL with
851 the bits that are constant, and then return an expression that
852 will perform the dynamic initialization. */
853 if (value != error_mark_node
854 && (TREE_SIDE_EFFECTS (value)
855 || array_of_runtime_bound_p (type)
856 || ! reduced_constant_expression_p (value)))
857 return split_nonconstant_init (decl, value);
858 /* If the value is a constant, just put it in DECL_INITIAL. If DECL
859 is an automatic variable, the middle end will turn this into a
860 dynamic initialization later. */
861 DECL_INITIAL (decl) = value;
866 /* Give diagnostic about narrowing conversions within { }. */
869 check_narrowing (tree type, tree init, tsubst_flags_t complain)
871 tree ftype = unlowered_expr_type (init);
875 if (((!warn_narrowing || !(complain & tf_warning))
876 && cxx_dialect == cxx98)
877 || !ARITHMETIC_TYPE_P (type))
880 if (BRACE_ENCLOSED_INITIALIZER_P (init)
881 && TREE_CODE (type) == COMPLEX_TYPE)
883 tree elttype = TREE_TYPE (type);
884 if (CONSTRUCTOR_NELTS (init) > 0)
885 ok &= check_narrowing (elttype, CONSTRUCTOR_ELT (init, 0)->value,
887 if (CONSTRUCTOR_NELTS (init) > 1)
888 ok &= check_narrowing (elttype, CONSTRUCTOR_ELT (init, 1)->value,
893 init = fold_non_dependent_expr (init);
895 if (TREE_CODE (type) == INTEGER_TYPE
896 && TREE_CODE (ftype) == REAL_TYPE)
898 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (ftype)
899 && CP_INTEGRAL_TYPE_P (type))
901 if (TREE_CODE (ftype) == ENUMERAL_TYPE)
902 /* Check for narrowing based on the values of the enumeration. */
903 ftype = ENUM_UNDERLYING_TYPE (ftype);
904 if ((tree_int_cst_lt (TYPE_MAX_VALUE (type),
905 TYPE_MAX_VALUE (ftype))
906 || tree_int_cst_lt (TYPE_MIN_VALUE (ftype),
907 TYPE_MIN_VALUE (type)))
908 && (TREE_CODE (init) != INTEGER_CST
909 || !int_fits_type_p (init, type)))
912 else if (TREE_CODE (ftype) == REAL_TYPE
913 && TREE_CODE (type) == REAL_TYPE)
915 if (TYPE_PRECISION (type) < TYPE_PRECISION (ftype))
917 if (TREE_CODE (init) == REAL_CST)
919 /* Issue 703: Loss of precision is OK as long as the value is
920 within the representable range of the new type. */
922 d = TREE_REAL_CST (init);
923 real_convert (&r, TYPE_MODE (type), &d);
931 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (ftype)
932 && TREE_CODE (type) == REAL_TYPE)
935 if (TREE_CODE (init) == INTEGER_CST)
937 d = real_value_from_int_cst (0, init);
938 if (exact_real_truncate (TYPE_MODE (type), &d))
945 if (cxx_dialect == cxx98)
946 warning_at (EXPR_LOC_OR_LOC (init, input_location), OPT_Wnarrowing,
947 "narrowing conversion of %qE from %qT to %qT inside { } "
948 "is ill-formed in C++11", init, ftype, type);
949 else if (!TREE_CONSTANT (init))
951 if (complain & tf_warning_or_error)
953 pedwarn (EXPR_LOC_OR_LOC (init, input_location), OPT_Wnarrowing,
954 "narrowing conversion of %qE from %qT to %qT inside { }",
959 else if (complain & tf_error)
960 error_at (EXPR_LOC_OR_LOC (init, input_location),
961 "narrowing conversion of %qE from %qT to %qT inside { }",
965 return cxx_dialect == cxx98 || ok;
968 /* Process the initializer INIT for a variable of type TYPE, emitting
969 diagnostics for invalid initializers and converting the initializer as
972 For aggregate types, it assumes that reshape_init has already run, thus the
973 initializer will have the right shape (brace elision has been undone).
975 NESTED is true iff we are being called for an element of a CONSTRUCTOR. */
978 digest_init_r (tree type, tree init, bool nested, int flags,
979 tsubst_flags_t complain)
981 enum tree_code code = TREE_CODE (type);
983 if (error_operand_p (init))
984 return error_mark_node;
988 /* We must strip the outermost array type when completing the type,
989 because the its bounds might be incomplete at the moment. */
990 if (!complete_type_or_maybe_complain (TREE_CODE (type) == ARRAY_TYPE
991 ? TREE_TYPE (type) : type, NULL_TREE,
993 return error_mark_node;
995 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue
996 (g++.old-deja/g++.law/casts2.C). */
997 if (TREE_CODE (init) == NON_LVALUE_EXPR)
998 init = TREE_OPERAND (init, 0);
1000 /* Initialization of an array of chars from a string constant. The initializer
1001 can be optionally enclosed in braces, but reshape_init has already removed
1002 them if they were present. */
1003 if (code == ARRAY_TYPE)
1005 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
1006 if (char_type_p (typ1)
1008 && TREE_CODE (init) == STRING_CST)
1010 tree char_type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (init)));
1012 if (TYPE_PRECISION (typ1) == BITS_PER_UNIT)
1014 if (char_type != char_type_node)
1016 if (complain & tf_error)
1017 error ("char-array initialized from wide string");
1018 return error_mark_node;
1023 if (char_type == char_type_node)
1025 if (complain & tf_error)
1026 error ("int-array initialized from non-wide string");
1027 return error_mark_node;
1029 else if (char_type != typ1)
1031 if (complain & tf_error)
1032 error ("int-array initialized from incompatible "
1034 return error_mark_node;
1038 if (type != TREE_TYPE (init))
1040 init = copy_node (init);
1041 TREE_TYPE (init) = type;
1043 if (TYPE_DOMAIN (type) != 0 && TREE_CONSTANT (TYPE_SIZE (type)))
1045 int size = TREE_INT_CST_LOW (TYPE_SIZE (type));
1046 size = (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
1047 /* In C it is ok to subtract 1 from the length of the string
1048 because it's ok to ignore the terminating null char that is
1049 counted in the length of the constant, but in C++ this would
1051 if (size < TREE_STRING_LENGTH (init))
1052 permerror (input_location, "initializer-string for array "
1053 "of chars is too long");
1059 /* Handle scalar types (including conversions) and references. */
1060 if ((TREE_CODE (type) != COMPLEX_TYPE
1061 || BRACE_ENCLOSED_INITIALIZER_P (init))
1062 && (SCALAR_TYPE_P (type) || code == REFERENCE_TYPE))
1067 flags |= LOOKUP_NO_NARROWING;
1068 init = convert_for_initialization (0, type, init, flags,
1069 ICR_INIT, NULL_TREE, 0,
1073 /* Skip any conversions since we'll be outputting the underlying
1075 while (CONVERT_EXPR_P (*exp)
1076 || TREE_CODE (*exp) == NON_LVALUE_EXPR)
1077 exp = &TREE_OPERAND (*exp, 0);
1079 *exp = cplus_expand_constant (*exp);
1084 /* Come here only for aggregates: records, arrays, unions, complex numbers
1086 gcc_assert (TREE_CODE (type) == ARRAY_TYPE
1087 || TREE_CODE (type) == VECTOR_TYPE
1088 || TREE_CODE (type) == RECORD_TYPE
1089 || TREE_CODE (type) == UNION_TYPE
1090 || TREE_CODE (type) == COMPLEX_TYPE);
1092 if (BRACE_ENCLOSED_INITIALIZER_P (init)
1093 && !TYPE_NON_AGGREGATE_CLASS (type))
1094 return process_init_constructor (type, init, complain);
1097 if (COMPOUND_LITERAL_P (init) && TREE_CODE (type) == ARRAY_TYPE)
1099 if (complain & tf_error)
1100 error ("cannot initialize aggregate of type %qT with "
1101 "a compound literal", type);
1103 return error_mark_node;
1106 if (TREE_CODE (type) == ARRAY_TYPE
1107 && !BRACE_ENCLOSED_INITIALIZER_P (init))
1109 /* Allow the result of build_array_copy and of
1110 build_value_init_noctor. */
1111 if ((TREE_CODE (init) == VEC_INIT_EXPR
1112 || TREE_CODE (init) == CONSTRUCTOR)
1113 && (same_type_ignoring_top_level_qualifiers_p
1114 (type, TREE_TYPE (init))))
1117 if (complain & tf_error)
1118 error ("array must be initialized with a brace-enclosed"
1120 return error_mark_node;
1123 return convert_for_initialization (NULL_TREE, type, init,
1125 ICR_INIT, NULL_TREE, 0,
1131 digest_init (tree type, tree init, tsubst_flags_t complain)
1133 return digest_init_r (type, init, false, LOOKUP_IMPLICIT, complain);
1137 digest_init_flags (tree type, tree init, int flags)
1139 return digest_init_r (type, init, false, flags, tf_warning_or_error);
1142 /* Process the initializer INIT for an NSDMI DECL (a FIELD_DECL). */
1144 digest_nsdmi_init (tree decl, tree init)
1146 gcc_assert (TREE_CODE (decl) == FIELD_DECL);
1148 int flags = LOOKUP_IMPLICIT;
1149 if (DIRECT_LIST_INIT_P (init))
1150 flags = LOOKUP_NORMAL;
1151 init = digest_init_flags (TREE_TYPE (decl), init, flags);
1152 if (TREE_CODE (init) == TARGET_EXPR)
1153 /* This represents the whole initialization. */
1154 TARGET_EXPR_DIRECT_INIT_P (init) = true;
1158 /* Set of flags used within process_init_constructor to describe the
1160 #define PICFLAG_ERRONEOUS 1
1161 #define PICFLAG_NOT_ALL_CONSTANT 2
1162 #define PICFLAG_NOT_ALL_SIMPLE 4
1163 #define PICFLAG_SIDE_EFFECTS 8
1165 /* Given an initializer INIT, return the flag (PICFLAG_*) which better
1169 picflag_from_initializer (tree init)
1171 if (init == error_mark_node)
1172 return PICFLAG_ERRONEOUS;
1173 else if (!TREE_CONSTANT (init))
1175 if (TREE_SIDE_EFFECTS (init))
1176 return PICFLAG_SIDE_EFFECTS;
1178 return PICFLAG_NOT_ALL_CONSTANT;
1180 else if (!initializer_constant_valid_p (init, TREE_TYPE (init)))
1181 return PICFLAG_NOT_ALL_SIMPLE;
1185 /* Adjust INIT for going into a CONSTRUCTOR. */
1188 massage_init_elt (tree type, tree init, tsubst_flags_t complain)
1190 init = digest_init_r (type, init, true, LOOKUP_IMPLICIT, complain);
1191 /* Strip a simple TARGET_EXPR when we know this is an initializer. */
1192 if (TREE_CODE (init) == TARGET_EXPR
1193 && !VOID_TYPE_P (TREE_TYPE (TARGET_EXPR_INITIAL (init))))
1194 init = TARGET_EXPR_INITIAL (init);
1195 /* When we defer constant folding within a statement, we may want to
1196 defer this folding as well. */
1197 tree t = fold_non_dependent_expr (init);
1198 t = maybe_constant_init (t);
1199 if (TREE_CONSTANT (t))
1204 /* Subroutine of process_init_constructor, which will process an initializer
1205 INIT for an array or vector of type TYPE. Returns the flags (PICFLAG_*)
1206 which describe the initializers. */
1209 process_init_constructor_array (tree type, tree init,
1210 tsubst_flags_t complain)
1212 unsigned HOST_WIDE_INT i, len = 0;
1214 bool unbounded = false;
1215 constructor_elt *ce;
1216 vec<constructor_elt, va_gc> *v = CONSTRUCTOR_ELTS (init);
1218 gcc_assert (TREE_CODE (type) == ARRAY_TYPE
1219 || TREE_CODE (type) == VECTOR_TYPE);
1221 if (TREE_CODE (type) == ARRAY_TYPE)
1223 tree domain = TYPE_DOMAIN (type);
1224 if (domain && TREE_CONSTANT (TYPE_MAX_VALUE (domain)))
1225 len = wi::ext (wi::to_offset (TYPE_MAX_VALUE (domain))
1226 - wi::to_offset (TYPE_MIN_VALUE (domain)) + 1,
1227 TYPE_PRECISION (TREE_TYPE (domain)),
1228 TYPE_SIGN (TREE_TYPE (domain))).to_uhwi ();
1230 unbounded = true; /* Take as many as there are. */
1233 /* Vectors are like simple fixed-size arrays. */
1234 len = TYPE_VECTOR_SUBPARTS (type);
1236 /* There must not be more initializers than needed. */
1237 if (!unbounded && vec_safe_length (v) > len)
1239 if (complain & tf_error)
1240 error ("too many initializers for %qT", type);
1242 return PICFLAG_ERRONEOUS;
1245 FOR_EACH_VEC_SAFE_ELT (v, i, ce)
1249 gcc_assert (TREE_CODE (ce->index) == INTEGER_CST);
1250 if (compare_tree_int (ce->index, i) != 0)
1252 ce->value = error_mark_node;
1253 sorry ("non-trivial designated initializers not supported");
1257 ce->index = size_int (i);
1258 gcc_assert (ce->value);
1259 ce->value = massage_init_elt (TREE_TYPE (type), ce->value, complain);
1261 if (ce->value != error_mark_node)
1262 gcc_assert (same_type_ignoring_top_level_qualifiers_p
1263 (TREE_TYPE (type), TREE_TYPE (ce->value)));
1265 flags |= picflag_from_initializer (ce->value);
1268 /* No more initializers. If the array is unbounded, we are done. Otherwise,
1269 we must add initializers ourselves. */
1271 for (; i < len; ++i)
1275 if (type_build_ctor_call (TREE_TYPE (type)))
1277 /* If this type needs constructors run for default-initialization,
1278 we can't rely on the back end to do it for us, so make the
1279 initialization explicit by list-initializing from T{}. */
1280 next = build_constructor (init_list_type_node, NULL);
1281 CONSTRUCTOR_IS_DIRECT_INIT (next) = true;
1282 next = massage_init_elt (TREE_TYPE (type), next, complain);
1283 if (initializer_zerop (next))
1284 /* The default zero-initialization is fine for us; don't
1285 add anything to the CONSTRUCTOR. */
1288 else if (!zero_init_p (TREE_TYPE (type)))
1289 next = build_zero_init (TREE_TYPE (type),
1290 /*nelts=*/NULL_TREE,
1291 /*static_storage_p=*/false);
1293 /* The default zero-initialization is fine for us; don't
1294 add anything to the CONSTRUCTOR. */
1299 flags |= picflag_from_initializer (next);
1300 CONSTRUCTOR_APPEND_ELT (v, size_int (i), next);
1304 CONSTRUCTOR_ELTS (init) = v;
1308 /* Subroutine of process_init_constructor, which will process an initializer
1309 INIT for a class of type TYPE. Returns the flags (PICFLAG_*) which describe
1310 the initializers. */
1313 process_init_constructor_record (tree type, tree init,
1314 tsubst_flags_t complain)
1316 vec<constructor_elt, va_gc> *v = NULL;
1320 gcc_assert (TREE_CODE (type) == RECORD_TYPE);
1321 gcc_assert (!CLASSTYPE_VBASECLASSES (type));
1322 gcc_assert (!TYPE_BINFO (type)
1323 || !BINFO_N_BASE_BINFOS (TYPE_BINFO (type)));
1324 gcc_assert (!TYPE_POLYMORPHIC_P (type));
1328 unsigned HOST_WIDE_INT idx = 0;
1329 /* Generally, we will always have an index for each initializer (which is
1330 a FIELD_DECL, put by reshape_init), but compound literals don't go trough
1331 reshape_init. So we need to handle both cases. */
1332 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
1337 if (!DECL_NAME (field) && DECL_C_BIT_FIELD (field))
1340 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1343 /* If this is a bitfield, first convert to the declared type. */
1344 type = TREE_TYPE (field);
1345 if (DECL_BIT_FIELD_TYPE (field))
1346 type = DECL_BIT_FIELD_TYPE (field);
1347 if (type == error_mark_node)
1348 return PICFLAG_ERRONEOUS;
1350 if (idx < vec_safe_length (CONSTRUCTOR_ELTS (init)))
1352 constructor_elt *ce = &(*CONSTRUCTOR_ELTS (init))[idx];
1355 /* We can have either a FIELD_DECL or an IDENTIFIER_NODE. The
1356 latter case can happen in templates where lookup has to be
1358 gcc_assert (TREE_CODE (ce->index) == FIELD_DECL
1359 || identifier_p (ce->index));
1360 if (ce->index != field
1361 && ce->index != DECL_NAME (field))
1363 ce->value = error_mark_node;
1364 sorry ("non-trivial designated initializers not supported");
1368 gcc_assert (ce->value);
1369 next = massage_init_elt (type, ce->value, complain);
1372 else if (DECL_INITIAL (field))
1376 /* We're using an NSDMI past a field with implicit
1377 zero-init. Go back and make it explicit. */
1379 vec_safe_truncate (v, 0);
1382 /* C++14 aggregate NSDMI. */
1383 next = get_nsdmi (field, /*ctor*/false);
1385 else if (type_build_ctor_call (TREE_TYPE (field)))
1387 /* If this type needs constructors run for
1388 default-initialization, we can't rely on the back end to do it
1389 for us, so build up TARGET_EXPRs. If the type in question is
1390 a class, just build one up; if it's an array, recurse. */
1391 next = build_constructor (init_list_type_node, NULL);
1392 /* Call this direct-initialization pending DR 1518 resolution so
1393 that explicit default ctors don't break valid C++03 code. */
1394 CONSTRUCTOR_IS_DIRECT_INIT (next) = true;
1395 next = massage_init_elt (TREE_TYPE (field), next, complain);
1397 /* Warn when some struct elements are implicitly initialized. */
1398 if ((complain & tf_warning)
1399 && !EMPTY_CONSTRUCTOR_P (init))
1400 warning (OPT_Wmissing_field_initializers,
1401 "missing initializer for member %qD", field);
1405 if (TREE_CODE (TREE_TYPE (field)) == REFERENCE_TYPE)
1407 if (complain & tf_error)
1408 error ("member %qD is uninitialized reference", field);
1410 return PICFLAG_ERRONEOUS;
1412 else if (CLASSTYPE_REF_FIELDS_NEED_INIT (TREE_TYPE (field)))
1414 if (complain & tf_error)
1415 error ("member %qD with uninitialized reference fields", field);
1417 return PICFLAG_ERRONEOUS;
1420 /* Warn when some struct elements are implicitly initialized
1422 if ((complain & tf_warning)
1423 && !EMPTY_CONSTRUCTOR_P (init))
1424 warning (OPT_Wmissing_field_initializers,
1425 "missing initializer for member %qD", field);
1427 if (!zero_init_p (TREE_TYPE (field))
1429 next = build_zero_init (TREE_TYPE (field), /*nelts=*/NULL_TREE,
1430 /*static_storage_p=*/false);
1433 /* The default zero-initialization is fine for us; don't
1434 add anything to the CONSTRUCTOR. */
1440 /* If this is a bitfield, now convert to the lowered type. */
1441 if (type != TREE_TYPE (field))
1442 next = cp_convert_and_check (TREE_TYPE (field), next, complain);
1443 flags |= picflag_from_initializer (next);
1444 CONSTRUCTOR_APPEND_ELT (v, field, next);
1447 if (idx < vec_safe_length (CONSTRUCTOR_ELTS (init)))
1449 if (complain & tf_error)
1450 error ("too many initializers for %qT", type);
1452 return PICFLAG_ERRONEOUS;
1455 CONSTRUCTOR_ELTS (init) = v;
1459 /* Subroutine of process_init_constructor, which will process a single
1460 initializer INIT for a union of type TYPE. Returns the flags (PICFLAG_*)
1461 which describe the initializer. */
1464 process_init_constructor_union (tree type, tree init,
1465 tsubst_flags_t complain)
1467 constructor_elt *ce;
1470 /* If the initializer was empty, use default zero initialization. */
1471 if (vec_safe_is_empty (CONSTRUCTOR_ELTS (init)))
1474 len = CONSTRUCTOR_ELTS (init)->length ();
1477 if (!(complain & tf_error))
1478 return PICFLAG_ERRONEOUS;
1479 error ("too many initializers for %qT", type);
1480 CONSTRUCTOR_ELTS (init)->block_remove (1, len-1);
1483 ce = &(*CONSTRUCTOR_ELTS (init))[0];
1485 /* If this element specifies a field, initialize via that field. */
1488 if (TREE_CODE (ce->index) == FIELD_DECL)
1490 else if (identifier_p (ce->index))
1492 /* This can happen within a cast, see g++.dg/opt/cse2.C. */
1493 tree name = ce->index;
1495 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1496 if (DECL_NAME (field) == name)
1500 if (complain & tf_error)
1501 error ("no field %qD found in union being initialized",
1503 ce->value = error_mark_node;
1509 gcc_assert (TREE_CODE (ce->index) == INTEGER_CST
1510 || TREE_CODE (ce->index) == RANGE_EXPR);
1511 if (complain & tf_error)
1512 error ("index value instead of field name in union initializer");
1513 ce->value = error_mark_node;
1518 /* Find the first named field. ANSI decided in September 1990
1519 that only named fields count here. */
1520 tree field = TYPE_FIELDS (type);
1521 while (field && (!DECL_NAME (field) || TREE_CODE (field) != FIELD_DECL))
1522 field = TREE_CHAIN (field);
1523 if (field == NULL_TREE)
1525 if (complain & tf_error)
1526 error ("too many initializers for %qT", type);
1527 ce->value = error_mark_node;
1532 if (ce->value && ce->value != error_mark_node)
1533 ce->value = massage_init_elt (TREE_TYPE (ce->index), ce->value, complain);
1535 return picflag_from_initializer (ce->value);
1538 /* Process INIT, a constructor for a variable of aggregate type TYPE. The
1539 constructor is a brace-enclosed initializer, and will be modified in-place.
1541 Each element is converted to the right type through digest_init, and
1542 missing initializers are added following the language rules (zero-padding,
1545 After the execution, the initializer will have TREE_CONSTANT if all elts are
1546 constant, and TREE_STATIC set if, in addition, all elts are simple enough
1547 constants that the assembler and linker can compute them.
1549 The function returns the initializer itself, or error_mark_node in case
1553 process_init_constructor (tree type, tree init, tsubst_flags_t complain)
1557 gcc_assert (BRACE_ENCLOSED_INITIALIZER_P (init));
1559 if (TREE_CODE (type) == ARRAY_TYPE || TREE_CODE (type) == VECTOR_TYPE)
1560 flags = process_init_constructor_array (type, init, complain);
1561 else if (TREE_CODE (type) == RECORD_TYPE)
1562 flags = process_init_constructor_record (type, init, complain);
1563 else if (TREE_CODE (type) == UNION_TYPE)
1564 flags = process_init_constructor_union (type, init, complain);
1568 if (flags & PICFLAG_ERRONEOUS)
1569 return error_mark_node;
1571 TREE_TYPE (init) = type;
1572 if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type) == NULL_TREE)
1573 cp_complete_array_type (&TREE_TYPE (init), init, /*do_default=*/0);
1574 if (flags & PICFLAG_SIDE_EFFECTS)
1576 TREE_CONSTANT (init) = false;
1577 TREE_SIDE_EFFECTS (init) = true;
1579 else if (flags & PICFLAG_NOT_ALL_CONSTANT)
1580 /* Make sure TREE_CONSTANT isn't set from build_constructor. */
1581 TREE_CONSTANT (init) = false;
1584 TREE_CONSTANT (init) = 1;
1585 if (!(flags & PICFLAG_NOT_ALL_SIMPLE))
1586 TREE_STATIC (init) = 1;
1591 /* Given a structure or union value DATUM, construct and return
1592 the structure or union component which results from narrowing
1593 that value to the base specified in BASETYPE. For example, given the
1596 class L { int ii; };
1597 class A : L { ... };
1598 class B : L { ... };
1599 class C : A, B { ... };
1607 x.A::ii refers to the ii member of the L part of
1608 the A part of the C object named by X. In this case,
1609 DATUM would be x, and BASETYPE would be A.
1611 I used to think that this was nonconformant, that the standard specified
1612 that first we look up ii in A, then convert x to an L& and pull out the
1613 ii part. But in fact, it does say that we convert x to an A&; A here
1614 is known as the "naming class". (jason 2000-12-19)
1616 BINFO_P points to a variable initialized either to NULL_TREE or to the
1617 binfo for the specific base subobject we want to convert to. */
1620 build_scoped_ref (tree datum, tree basetype, tree* binfo_p)
1624 if (datum == error_mark_node)
1625 return error_mark_node;
1629 binfo = lookup_base (TREE_TYPE (datum), basetype, ba_check,
1630 NULL, tf_warning_or_error);
1632 if (!binfo || binfo == error_mark_node)
1634 *binfo_p = NULL_TREE;
1636 error_not_base_type (basetype, TREE_TYPE (datum));
1637 return error_mark_node;
1641 return build_base_path (PLUS_EXPR, datum, binfo, 1,
1642 tf_warning_or_error);
1645 /* Build a reference to an object specified by the C++ `->' operator.
1646 Usually this just involves dereferencing the object, but if the
1647 `->' operator is overloaded, then such overloads must be
1648 performed until an object which does not have the `->' operator
1649 overloaded is found. An error is reported when circular pointer
1650 delegation is detected. */
1653 build_x_arrow (location_t loc, tree expr, tsubst_flags_t complain)
1655 tree orig_expr = expr;
1656 tree type = TREE_TYPE (expr);
1657 tree last_rval = NULL_TREE;
1658 vec<tree, va_gc> *types_memoized = NULL;
1660 if (type == error_mark_node)
1661 return error_mark_node;
1663 if (processing_template_decl)
1665 if (type_dependent_expression_p (expr))
1666 return build_min_nt_loc (loc, ARROW_EXPR, expr);
1667 expr = build_non_dependent_expr (expr);
1670 if (MAYBE_CLASS_TYPE_P (type))
1672 struct tinst_level *actual_inst = current_instantiation ();
1675 while ((expr = build_new_op (loc, COMPONENT_REF,
1676 LOOKUP_NORMAL, expr, NULL_TREE, NULL_TREE,
1679 if (expr == error_mark_node)
1680 return error_mark_node;
1682 /* This provides a better instantiation backtrace in case of
1684 if (fn && DECL_USE_TEMPLATE (fn))
1685 push_tinst_level_loc (fn,
1686 (current_instantiation () != actual_inst)
1687 ? DECL_SOURCE_LOCATION (fn)
1691 if (vec_member (TREE_TYPE (expr), types_memoized))
1693 if (complain & tf_error)
1694 error ("circular pointer delegation detected");
1695 return error_mark_node;
1698 vec_safe_push (types_memoized, TREE_TYPE (expr));
1702 while (current_instantiation () != actual_inst)
1705 if (last_rval == NULL_TREE)
1707 if (complain & tf_error)
1708 error ("base operand of %<->%> has non-pointer type %qT", type);
1709 return error_mark_node;
1712 if (TREE_CODE (TREE_TYPE (last_rval)) == REFERENCE_TYPE)
1713 last_rval = convert_from_reference (last_rval);
1716 last_rval = decay_conversion (expr, complain);
1718 if (TYPE_PTR_P (TREE_TYPE (last_rval)))
1720 if (processing_template_decl)
1722 expr = build_min (ARROW_EXPR, TREE_TYPE (TREE_TYPE (last_rval)),
1724 TREE_SIDE_EFFECTS (expr) = TREE_SIDE_EFFECTS (last_rval);
1728 return cp_build_indirect_ref (last_rval, RO_NULL, complain);
1731 if (complain & tf_error)
1734 error ("result of %<operator->()%> yields non-pointer result");
1736 error ("base operand of %<->%> is not a pointer");
1738 return error_mark_node;
1741 /* Return an expression for "DATUM .* COMPONENT". DATUM has not
1742 already been checked out to be of aggregate type. */
1745 build_m_component_ref (tree datum, tree component, tsubst_flags_t complain)
1753 if (error_operand_p (datum) || error_operand_p (component))
1754 return error_mark_node;
1756 datum = mark_lvalue_use (datum);
1757 component = mark_rvalue_use (component);
1759 ptrmem_type = TREE_TYPE (component);
1760 if (!TYPE_PTRMEM_P (ptrmem_type))
1762 if (complain & tf_error)
1763 error ("%qE cannot be used as a member pointer, since it is of "
1764 "type %qT", component, ptrmem_type);
1765 return error_mark_node;
1768 objtype = TYPE_MAIN_VARIANT (TREE_TYPE (datum));
1769 if (! MAYBE_CLASS_TYPE_P (objtype))
1771 if (complain & tf_error)
1772 error ("cannot apply member pointer %qE to %qE, which is of "
1773 "non-class type %qT", component, datum, objtype);
1774 return error_mark_node;
1777 type = TYPE_PTRMEM_POINTED_TO_TYPE (ptrmem_type);
1778 ctype = complete_type (TYPE_PTRMEM_CLASS_TYPE (ptrmem_type));
1780 if (!COMPLETE_TYPE_P (ctype))
1782 if (!same_type_p (ctype, objtype))
1788 binfo = lookup_base (objtype, ctype, ba_check, NULL, complain);
1793 if (complain & tf_error)
1794 error ("pointer to member type %qT incompatible with object "
1795 "type %qT", type, objtype);
1796 return error_mark_node;
1798 else if (binfo == error_mark_node)
1799 return error_mark_node;
1802 if (TYPE_PTRDATAMEM_P (ptrmem_type))
1804 cp_lvalue_kind kind = lvalue_kind (datum);
1807 /* Compute the type of the field, as described in [expr.ref].
1808 There's no such thing as a mutable pointer-to-member, so
1809 things are not as complex as they are for references to
1810 non-static data members. */
1811 type = cp_build_qualified_type (type,
1812 (cp_type_quals (type)
1813 | cp_type_quals (TREE_TYPE (datum))));
1815 datum = build_address (datum);
1817 /* Convert object to the correct base. */
1820 datum = build_base_path (PLUS_EXPR, datum, binfo, 1, complain);
1821 if (datum == error_mark_node)
1822 return error_mark_node;
1825 /* Build an expression for "object + offset" where offset is the
1826 value stored in the pointer-to-data-member. */
1827 ptype = build_pointer_type (type);
1828 datum = fold_build_pointer_plus (fold_convert (ptype, datum), component);
1829 datum = cp_build_indirect_ref (datum, RO_NULL, complain);
1830 if (datum == error_mark_node)
1831 return error_mark_node;
1833 /* If the object expression was an rvalue, return an rvalue. */
1834 if (kind & clk_class)
1835 datum = rvalue (datum);
1836 else if (kind & clk_rvalueref)
1837 datum = move (datum);
1842 /* 5.5/6: In a .* expression whose object expression is an rvalue, the
1843 program is ill-formed if the second operand is a pointer to member
1844 function with ref-qualifier &. In a .* expression whose object
1845 expression is an lvalue, the program is ill-formed if the second
1846 operand is a pointer to member function with ref-qualifier &&. */
1847 if (FUNCTION_REF_QUALIFIED (type))
1849 bool lval = real_lvalue_p (datum);
1850 if (lval && FUNCTION_RVALUE_QUALIFIED (type))
1852 if (complain & tf_error)
1853 error ("pointer-to-member-function type %qT requires an rvalue",
1855 return error_mark_node;
1857 else if (!lval && !FUNCTION_RVALUE_QUALIFIED (type))
1859 if (complain & tf_error)
1860 error ("pointer-to-member-function type %qT requires an lvalue",
1862 return error_mark_node;
1865 return build2 (OFFSET_REF, type, datum, component);
1869 /* Return a tree node for the expression TYPENAME '(' PARMS ')'. */
1872 build_functional_cast (tree exp, tree parms, tsubst_flags_t complain)
1874 /* This is either a call to a constructor,
1875 or a C cast in C++'s `functional' notation. */
1877 /* The type to which we are casting. */
1879 vec<tree, va_gc> *parmvec;
1881 if (error_operand_p (exp) || parms == error_mark_node)
1882 return error_mark_node;
1884 if (TREE_CODE (exp) == TYPE_DECL)
1886 type = TREE_TYPE (exp);
1888 if (complain & tf_warning
1889 && TREE_DEPRECATED (type)
1890 && DECL_ARTIFICIAL (exp))
1891 warn_deprecated_use (type, NULL_TREE);
1896 /* We need to check this explicitly, since value-initialization of
1897 arrays is allowed in other situations. */
1898 if (TREE_CODE (type) == ARRAY_TYPE)
1900 if (complain & tf_error)
1901 error ("functional cast to array type %qT", type);
1902 return error_mark_node;
1905 if (type_uses_auto (type))
1907 if (complain & tf_error)
1908 error ("invalid use of %<auto%>");
1909 return error_mark_node;
1912 if (processing_template_decl)
1916 /* Diagnose this even in a template. We could also try harder
1917 to give all the usual errors when the type and args are
1919 if (TREE_CODE (type) == REFERENCE_TYPE && !parms)
1921 if (complain & tf_error)
1922 error ("invalid value-initialization of reference type");
1923 return error_mark_node;
1926 t = build_min (CAST_EXPR, type, parms);
1927 /* We don't know if it will or will not have side effects. */
1928 TREE_SIDE_EFFECTS (t) = 1;
1932 if (! MAYBE_CLASS_TYPE_P (type))
1934 if (parms == NULL_TREE)
1936 if (VOID_TYPE_P (type))
1938 return build_value_init (cv_unqualified (type), complain);
1941 /* This must build a C cast. */
1942 parms = build_x_compound_expr_from_list (parms, ELK_FUNC_CAST, complain);
1943 return cp_build_c_cast (type, parms, complain);
1946 /* Prepare to evaluate as a call to a constructor. If this expression
1947 is actually used, for example,
1949 return X (arg1, arg2, ...);
1951 then the slot being initialized will be filled in. */
1953 if (!complete_type_or_maybe_complain (type, NULL_TREE, complain))
1954 return error_mark_node;
1955 if (abstract_virtuals_error_sfinae (ACU_CAST, type, complain))
1956 return error_mark_node;
1960 If the expression list is a single-expression, the type
1961 conversion is equivalent (in definedness, and if defined in
1962 meaning) to the corresponding cast expression. */
1963 if (parms && TREE_CHAIN (parms) == NULL_TREE)
1964 return cp_build_c_cast (type, TREE_VALUE (parms), complain);
1968 The expression T(), where T is a simple-type-specifier for a
1969 non-array complete object type or the (possibly cv-qualified)
1970 void type, creates an rvalue of the specified type, which is
1971 value-initialized. */
1973 if (parms == NULL_TREE)
1975 exp = build_value_init (type, complain);
1976 exp = get_target_expr_sfinae (exp, complain);
1980 /* Call the constructor. */
1981 parmvec = make_tree_vector ();
1982 for (; parms != NULL_TREE; parms = TREE_CHAIN (parms))
1983 vec_safe_push (parmvec, TREE_VALUE (parms));
1984 exp = build_special_member_call (NULL_TREE, complete_ctor_identifier,
1985 &parmvec, type, LOOKUP_NORMAL, complain);
1986 release_tree_vector (parmvec);
1988 if (exp == error_mark_node)
1989 return error_mark_node;
1991 return build_cplus_new (type, exp, complain);
1995 /* Add new exception specifier SPEC, to the LIST we currently have.
1996 If it's already in LIST then do nothing.
1997 Moan if it's bad and we're allowed to. COMPLAIN < 0 means we
1998 know what we're doing. */
2001 add_exception_specifier (tree list, tree spec, int complain)
2006 diagnostic_t diag_type = DK_UNSPECIFIED; /* none */
2008 if (spec == error_mark_node)
2011 gcc_assert (spec && (!list || TREE_VALUE (list)));
2013 /* [except.spec] 1, type in an exception specifier shall not be
2014 incomplete, or pointer or ref to incomplete other than pointer
2016 is_ptr = TYPE_PTR_P (core);
2017 if (is_ptr || TREE_CODE (core) == REFERENCE_TYPE)
2018 core = TREE_TYPE (core);
2021 else if (VOID_TYPE_P (core))
2023 else if (TREE_CODE (core) == TEMPLATE_TYPE_PARM)
2025 else if (processing_template_decl)
2030 /* 15.4/1 says that types in an exception specifier must be complete,
2031 but it seems more reasonable to only require this on definitions
2032 and calls. So just give a pedwarn at this point; we will give an
2033 error later if we hit one of those two cases. */
2034 if (!COMPLETE_TYPE_P (complete_type (core)))
2035 diag_type = DK_PEDWARN; /* pedwarn */
2042 for (probe = list; probe; probe = TREE_CHAIN (probe))
2043 if (same_type_p (TREE_VALUE (probe), spec))
2046 list = tree_cons (NULL_TREE, spec, list);
2049 diag_type = DK_ERROR; /* error */
2051 if (diag_type != DK_UNSPECIFIED
2052 && (complain & tf_warning_or_error))
2053 cxx_incomplete_type_diagnostic (NULL_TREE, core, diag_type);
2058 /* Like nothrow_spec_p, but don't abort on deferred noexcept. */
2061 nothrow_spec_p_uninst (const_tree spec)
2063 if (DEFERRED_NOEXCEPT_SPEC_P (spec))
2065 return nothrow_spec_p (spec);
2068 /* Combine the two exceptions specifier lists LIST and ADD, and return
2072 merge_exception_specifiers (tree list, tree add)
2074 tree noex, orig_list;
2076 /* No exception-specifier or noexcept(false) are less strict than
2077 anything else. Prefer the newer variant (LIST). */
2078 if (!list || list == noexcept_false_spec)
2080 else if (!add || add == noexcept_false_spec)
2083 /* noexcept(true) and throw() are stricter than anything else.
2084 As above, prefer the more recent one (LIST). */
2085 if (nothrow_spec_p_uninst (add))
2088 /* Two implicit noexcept specs (e.g. on a destructor) are equivalent. */
2089 if (UNEVALUATED_NOEXCEPT_SPEC_P (add)
2090 && UNEVALUATED_NOEXCEPT_SPEC_P (list))
2092 /* We should have instantiated other deferred noexcept specs by now. */
2093 gcc_assert (!DEFERRED_NOEXCEPT_SPEC_P (add));
2095 if (nothrow_spec_p_uninst (list))
2097 noex = TREE_PURPOSE (list);
2098 gcc_checking_assert (!TREE_PURPOSE (add)
2099 || cp_tree_equal (noex, TREE_PURPOSE (add)));
2101 /* Combine the dynamic-exception-specifiers, if any. */
2103 for (; add && TREE_VALUE (add); add = TREE_CHAIN (add))
2105 tree spec = TREE_VALUE (add);
2108 for (probe = orig_list; probe && TREE_VALUE (probe);
2109 probe = TREE_CHAIN (probe))
2110 if (same_type_p (TREE_VALUE (probe), spec))
2114 spec = build_tree_list (NULL_TREE, spec);
2115 TREE_CHAIN (spec) = list;
2120 /* Keep the noexcept-specifier at the beginning of the list. */
2121 if (noex != TREE_PURPOSE (list))
2122 list = tree_cons (noex, TREE_VALUE (list), TREE_CHAIN (list));
2127 /* Subroutine of build_call. Ensure that each of the types in the
2128 exception specification is complete. Technically, 15.4/1 says that
2129 they need to be complete when we see a declaration of the function,
2130 but we should be able to get away with only requiring this when the
2131 function is defined or called. See also add_exception_specifier. */
2134 require_complete_eh_spec_types (tree fntype, tree decl)
2137 /* Don't complain about calls to op new. */
2138 if (decl && DECL_ARTIFICIAL (decl))
2140 for (raises = TYPE_RAISES_EXCEPTIONS (fntype); raises;
2141 raises = TREE_CHAIN (raises))
2143 tree type = TREE_VALUE (raises);
2144 if (type && !COMPLETE_TYPE_P (type))
2148 ("call to function %qD which throws incomplete type %q#T",
2151 error ("call to function which throws incomplete type %q#T",
2158 #include "gt-cp-typeck2.h"