1 /* Report error messages, build initializers, and perform
2 some front-end optimizations for C++ compiler.
3 Copyright (C) 1987-2017 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"
32 #include "stor-layout.h"
37 process_init_constructor (tree type
, tree init
, tsubst_flags_t complain
);
40 /* Print an error message stemming from an attempt to use
41 BASETYPE as a base class for TYPE. */
44 error_not_base_type (tree basetype
, tree type
)
46 if (TREE_CODE (basetype
) == FUNCTION_DECL
)
47 basetype
= DECL_CONTEXT (basetype
);
48 error ("type %qT is not a base type for type %qT", basetype
, type
);
49 return error_mark_node
;
53 binfo_or_else (tree base
, tree type
)
55 tree binfo
= lookup_base (type
, base
, ba_unique
,
56 NULL
, tf_warning_or_error
);
58 if (binfo
== error_mark_node
)
61 error_not_base_type (base
, type
);
65 /* According to ARM $7.1.6, "A `const' object may be initialized, but its
66 value may not be changed thereafter. */
69 cxx_readonly_error (tree arg
, enum lvalue_use errstring
)
72 /* This macro is used to emit diagnostics to ensure that all format
73 strings are complete sentences, visible to gettext and checked at
76 #define ERROR_FOR_ASSIGNMENT(AS, ASM, IN, DE, ARG) \
97 /* Handle C++-specific things first. */
100 && DECL_LANG_SPECIFIC (arg
)
101 && DECL_IN_AGGR_P (arg
)
102 && !TREE_STATIC (arg
))
103 ERROR_FOR_ASSIGNMENT (G_("assignment of "
104 "constant field %qD"),
105 G_("constant field %qD "
106 "used as %<asm%> output"),
108 "constant field %qD"),
110 "constant field %qD"),
112 else if (INDIRECT_REF_P (arg
)
113 && TREE_CODE (TREE_TYPE (TREE_OPERAND (arg
, 0))) == REFERENCE_TYPE
114 && (VAR_P (TREE_OPERAND (arg
, 0))
115 || TREE_CODE (TREE_OPERAND (arg
, 0)) == PARM_DECL
))
116 ERROR_FOR_ASSIGNMENT (G_("assignment of "
117 "read-only reference %qD"),
118 G_("read-only reference %qD "
119 "used as %<asm%> output"),
121 "read-only reference %qD"),
123 "read-only reference %qD"),
124 TREE_OPERAND (arg
, 0));
126 readonly_error (input_location
, arg
, errstring
);
130 /* Structure that holds information about declarations whose type was
131 incomplete and we could not check whether it was abstract or not. */
133 struct GTY((chain_next ("%h.next"), for_user
)) pending_abstract_type
{
134 /* Declaration which we are checking for abstractness. It is either
135 a DECL node, or an IDENTIFIER_NODE if we do not have a full
136 declaration available. */
139 /* Type which will be checked for abstractness. */
142 /* Kind of use in an unnamed declarator. */
143 enum abstract_class_use use
;
145 /* Position of the declaration. This is only needed for IDENTIFIER_NODEs,
146 because DECLs already carry locus information. */
149 /* Link to the next element in list. */
150 struct pending_abstract_type
* next
;
153 struct abstract_type_hasher
: ggc_ptr_hash
<pending_abstract_type
>
155 typedef tree compare_type
;
156 static hashval_t
hash (pending_abstract_type
*);
157 static bool equal (pending_abstract_type
*, tree
);
160 /* Compute the hash value of the node VAL. This function is used by the
161 hash table abstract_pending_vars. */
164 abstract_type_hasher::hash (pending_abstract_type
*pat
)
166 return (hashval_t
) TYPE_UID (pat
->type
);
170 /* Compare node VAL1 with the type VAL2. This function is used by the
171 hash table abstract_pending_vars. */
174 abstract_type_hasher::equal (pending_abstract_type
*pat1
, tree type2
)
176 return (pat1
->type
== type2
);
179 /* Hash table that maintains pending_abstract_type nodes, for which we still
180 need to check for type abstractness. The key of the table is the type
181 of the declaration. */
182 static GTY (()) hash_table
<abstract_type_hasher
> *abstract_pending_vars
= NULL
;
184 static int abstract_virtuals_error_sfinae (tree
, tree
, abstract_class_use
, tsubst_flags_t
);
186 /* This function is called after TYPE is completed, and will check if there
187 are pending declarations for which we still need to verify the abstractness
188 of TYPE, and emit a diagnostic (through abstract_virtuals_error) if TYPE
189 turned out to be incomplete. */
192 complete_type_check_abstract (tree type
)
194 struct pending_abstract_type
*pat
;
195 location_t cur_loc
= input_location
;
197 gcc_assert (COMPLETE_TYPE_P (type
));
199 if (!abstract_pending_vars
)
202 /* Retrieve the list of pending declarations for this type. */
203 pending_abstract_type
**slot
204 = abstract_pending_vars
->find_slot_with_hash (type
, TYPE_UID (type
),
211 /* If the type is not abstract, do not do anything. */
212 if (CLASSTYPE_PURE_VIRTUALS (type
))
214 struct pending_abstract_type
*prev
= 0, *next
;
216 /* Reverse the list to emit the errors in top-down order. */
217 for (; pat
; pat
= next
)
225 /* Go through the list, and call abstract_virtuals_error for each
226 element: it will issue a diagnostic if the type is abstract. */
229 gcc_assert (type
== pat
->type
);
231 /* Tweak input_location so that the diagnostic appears at the correct
232 location. Notice that this is only needed if the decl is an
234 input_location
= pat
->locus
;
235 abstract_virtuals_error_sfinae (pat
->decl
, pat
->type
, pat
->use
,
236 tf_warning_or_error
);
241 abstract_pending_vars
->clear_slot (slot
);
243 input_location
= cur_loc
;
247 /* If TYPE has abstract virtual functions, issue an error about trying
248 to create an object of that type. DECL is the object declared, or
249 NULL_TREE if the declaration is unavailable, in which case USE specifies
250 the kind of invalid use. Returns 1 if an error occurred; zero if
254 abstract_virtuals_error_sfinae (tree decl
, tree type
, abstract_class_use use
,
255 tsubst_flags_t complain
)
257 vec
<tree
, va_gc
> *pure
;
259 /* This function applies only to classes. Any other entity can never
261 if (!CLASS_TYPE_P (type
))
263 type
= TYPE_MAIN_VARIANT (type
);
266 /* Instantiation here seems to be required by the standard,
267 but breaks e.g. boost::bind. FIXME! */
268 /* In SFINAE, non-N3276 context, force instantiation. */
269 if (!(complain
& (tf_error
|tf_decltype
)))
270 complete_type (type
);
273 /* If the type is incomplete, we register it within a hash table,
274 so that we can check again once it is completed. This makes sense
275 only for objects for which we have a declaration or at least a
277 if (!COMPLETE_TYPE_P (type
) && (complain
& tf_error
))
279 struct pending_abstract_type
*pat
;
281 gcc_assert (!decl
|| DECL_P (decl
) || identifier_p (decl
));
283 if (!abstract_pending_vars
)
284 abstract_pending_vars
285 = hash_table
<abstract_type_hasher
>::create_ggc (31);
287 pending_abstract_type
**slot
288 = abstract_pending_vars
->find_slot_with_hash (type
, TYPE_UID (type
),
291 pat
= ggc_alloc
<pending_abstract_type
> ();
295 pat
->locus
= ((decl
&& DECL_P (decl
))
296 ? DECL_SOURCE_LOCATION (decl
)
305 if (!TYPE_SIZE (type
))
306 /* TYPE is being defined, and during that time
307 CLASSTYPE_PURE_VIRTUALS holds the inline friends. */
310 pure
= CLASSTYPE_PURE_VIRTUALS (type
);
314 if (!(complain
& tf_error
))
320 error ("cannot declare variable %q+D to be of abstract "
321 "type %qT", decl
, type
);
322 else if (TREE_CODE (decl
) == PARM_DECL
)
324 if (DECL_NAME (decl
))
325 error ("cannot declare parameter %q+D to be of abstract type %qT",
328 error ("cannot declare parameter to be of abstract type %qT",
331 else if (TREE_CODE (decl
) == FIELD_DECL
)
332 error ("cannot declare field %q+D to be of abstract type %qT",
334 else if (TREE_CODE (decl
) == FUNCTION_DECL
335 && TREE_CODE (TREE_TYPE (decl
)) == METHOD_TYPE
)
336 error ("invalid abstract return type for member function %q+#D", decl
);
337 else if (TREE_CODE (decl
) == FUNCTION_DECL
)
338 error ("invalid abstract return type for function %q+#D", decl
);
339 else if (identifier_p (decl
))
340 /* Here we do not have location information. */
341 error ("invalid abstract type %qT for %qE", type
, decl
);
343 error ("invalid abstract type for %q+D", decl
);
348 error ("creating array of %qT, which is an abstract class type", type
);
351 error ("invalid cast to abstract class type %qT", type
);
354 error ("invalid new-expression of abstract class type %qT", type
);
357 error ("invalid abstract return type %qT", type
);
360 error ("invalid abstract parameter type %qT", type
);
363 error ("expression of abstract class type %qT cannot "
364 "be used in throw-expression", type
);
367 error ("cannot declare catch parameter to be of abstract "
368 "class type %qT", type
);
371 error ("cannot allocate an object of abstract type %qT", type
);
374 /* Only go through this once. */
380 inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (type
)),
381 " because the following virtual functions are pure within %qT:",
384 FOR_EACH_VEC_ELT (*pure
, ix
, fn
)
385 if (! DECL_CLONED_FUNCTION_P (fn
)
386 || DECL_COMPLETE_DESTRUCTOR_P (fn
))
387 inform (DECL_SOURCE_LOCATION (fn
), "\t%#qD", fn
);
389 /* Now truncate the vector. This leaves it non-null, so we know
390 there are pure virtuals, but empty so we don't list them out
399 abstract_virtuals_error_sfinae (tree decl
, tree type
, tsubst_flags_t complain
)
401 return abstract_virtuals_error_sfinae (decl
, type
, ACU_UNKNOWN
, complain
);
405 abstract_virtuals_error_sfinae (abstract_class_use use
, tree type
,
406 tsubst_flags_t complain
)
408 return abstract_virtuals_error_sfinae (NULL_TREE
, type
, use
, complain
);
412 /* Wrapper for the above function in the common case of wanting errors. */
415 abstract_virtuals_error (tree decl
, tree type
)
417 return abstract_virtuals_error_sfinae (decl
, type
, tf_warning_or_error
);
421 abstract_virtuals_error (abstract_class_use use
, tree type
)
423 return abstract_virtuals_error_sfinae (use
, type
, tf_warning_or_error
);
426 /* Print an inform about the declaration of the incomplete type TYPE. */
429 cxx_incomplete_type_inform (const_tree type
)
431 if (!TYPE_MAIN_DECL (type
))
434 location_t loc
= DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (type
));
435 tree ptype
= strip_top_quals (CONST_CAST_TREE (type
));
437 if (current_class_type
438 && TYPE_BEING_DEFINED (current_class_type
)
439 && same_type_p (ptype
, current_class_type
))
440 inform (loc
, "definition of %q#T is not complete until "
441 "the closing brace", ptype
);
442 else if (!TYPE_TEMPLATE_INFO (ptype
))
443 inform (loc
, "forward declaration of %q#T", ptype
);
445 inform (loc
, "declaration of %q#T", ptype
);
448 /* Print an error message for invalid use of an incomplete type.
449 VALUE is the expression that was used (or 0 if that isn't known)
450 and TYPE is the type that was invalid. DIAG_KIND indicates the
451 type of diagnostic (see diagnostic.def). */
454 cxx_incomplete_type_diagnostic (location_t loc
, const_tree value
,
455 const_tree type
, diagnostic_t diag_kind
)
457 bool is_decl
= false, complained
= false;
459 gcc_assert (diag_kind
== DK_WARNING
460 || diag_kind
== DK_PEDWARN
461 || diag_kind
== DK_ERROR
);
463 /* Avoid duplicate error message. */
464 if (TREE_CODE (type
) == ERROR_MARK
)
467 if (value
!= 0 && (VAR_P (value
)
468 || TREE_CODE (value
) == PARM_DECL
469 || TREE_CODE (value
) == FIELD_DECL
))
471 complained
= emit_diagnostic (diag_kind
, DECL_SOURCE_LOCATION (value
), 0,
472 "%qD has incomplete type", value
);
476 /* We must print an error message. Be clever about what it says. */
478 switch (TREE_CODE (type
))
484 complained
= emit_diagnostic (diag_kind
, loc
, 0,
485 "invalid use of incomplete type %q#T",
488 cxx_incomplete_type_inform (type
);
492 emit_diagnostic (diag_kind
, loc
, 0,
493 "invalid use of %qT", type
);
497 if (TYPE_DOMAIN (type
))
499 type
= TREE_TYPE (type
);
502 emit_diagnostic (diag_kind
, loc
, 0,
503 "invalid use of array with unspecified bounds");
509 tree member
= TREE_OPERAND (value
, 1);
510 if (is_overloaded_fn (member
))
511 member
= get_first_fn (member
);
513 if (DECL_FUNCTION_MEMBER_P (member
)
514 && ! flag_ms_extensions
)
515 emit_diagnostic (diag_kind
, loc
, 0,
516 "invalid use of member function %qD "
517 "(did you forget the %<()%> ?)", member
);
519 emit_diagnostic (diag_kind
, loc
, 0,
520 "invalid use of member %qD "
521 "(did you forget the %<&%> ?)", member
);
525 case TEMPLATE_TYPE_PARM
:
528 if (CLASS_PLACEHOLDER_TEMPLATE (type
))
529 emit_diagnostic (diag_kind
, loc
, 0,
530 "invalid use of placeholder %qT", type
);
532 emit_diagnostic (diag_kind
, loc
, 0,
533 "invalid use of %qT", type
);
536 emit_diagnostic (diag_kind
, loc
, 0,
537 "invalid use of template type parameter %qT", type
);
540 case BOUND_TEMPLATE_TEMPLATE_PARM
:
541 emit_diagnostic (diag_kind
, loc
, 0,
542 "invalid use of template template parameter %qT",
548 emit_diagnostic (diag_kind
, loc
, 0,
549 "invalid use of dependent type %qT", type
);
553 if (type
== init_list_type_node
)
555 emit_diagnostic (diag_kind
, loc
, 0,
556 "invalid use of brace-enclosed initializer list");
559 gcc_assert (type
== unknown_type_node
);
560 if (value
&& TREE_CODE (value
) == COMPONENT_REF
)
562 else if (value
&& TREE_CODE (value
) == ADDR_EXPR
)
563 emit_diagnostic (diag_kind
, loc
, 0,
564 "address of overloaded function with no contextual "
566 else if (value
&& TREE_CODE (value
) == OVERLOAD
)
567 emit_diagnostic (diag_kind
, loc
, 0,
568 "overloaded function with no contextual type information");
570 emit_diagnostic (diag_kind
, loc
, 0,
571 "insufficient contextual information to determine type");
579 /* Print an error message for invalid use of an incomplete type.
580 VALUE is the expression that was used (or 0 if that isn't known)
581 and TYPE is the type that was invalid. */
584 cxx_incomplete_type_error (location_t loc
, const_tree value
, const_tree type
)
586 cxx_incomplete_type_diagnostic (loc
, value
, type
, DK_ERROR
);
590 /* The recursive part of split_nonconstant_init. DEST is an lvalue
591 expression to which INIT should be assigned. INIT is a CONSTRUCTOR.
592 Return true if the whole of the value was initialized by the
593 generated statements. */
596 split_nonconstant_init_1 (tree dest
, tree init
)
598 unsigned HOST_WIDE_INT idx
;
599 tree field_index
, value
;
600 tree type
= TREE_TYPE (dest
);
601 tree inner_type
= NULL
;
602 bool array_type_p
= false;
603 bool complete_p
= true;
604 HOST_WIDE_INT num_split_elts
= 0;
606 switch (TREE_CODE (type
))
609 inner_type
= TREE_TYPE (type
);
611 if ((TREE_SIDE_EFFECTS (init
)
612 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
613 || array_of_runtime_bound_p (type
))
615 /* For an array, we only need/want a single cleanup region rather
616 than one per element. */
617 tree code
= build_vec_init (dest
, NULL_TREE
, init
, false, 1,
618 tf_warning_or_error
);
626 case QUAL_UNION_TYPE
:
627 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init
), idx
,
630 /* The current implementation of this algorithm assumes that
631 the field was set for all the elements. This is usually done
632 by process_init_constructor. */
633 gcc_assert (field_index
);
636 inner_type
= TREE_TYPE (field_index
);
638 if (TREE_CODE (value
) == CONSTRUCTOR
)
643 sub
= build4 (ARRAY_REF
, inner_type
, dest
, field_index
,
644 NULL_TREE
, NULL_TREE
);
646 sub
= build3 (COMPONENT_REF
, inner_type
, dest
, field_index
,
649 if (!split_nonconstant_init_1 (sub
, value
))
652 CONSTRUCTOR_ELTS (init
)->ordered_remove (idx
--);
655 else if (!initializer_constant_valid_p (value
, inner_type
))
660 /* FIXME: Ordered removal is O(1) so the whole function is
661 worst-case quadratic. This could be fixed using an aside
662 bitmap to record which elements must be removed and remove
663 them all at the same time. Or by merging
664 split_non_constant_init into process_init_constructor_array,
665 that is separating constants from non-constants while building
667 CONSTRUCTOR_ELTS (init
)->ordered_remove (idx
);
670 if (TREE_CODE (field_index
) == RANGE_EXPR
)
672 /* Use build_vec_init to initialize a range. */
673 tree low
= TREE_OPERAND (field_index
, 0);
674 tree hi
= TREE_OPERAND (field_index
, 1);
675 sub
= build4 (ARRAY_REF
, inner_type
, dest
, low
,
676 NULL_TREE
, NULL_TREE
);
677 sub
= cp_build_addr_expr (sub
, tf_warning_or_error
);
678 tree max
= size_binop (MINUS_EXPR
, hi
, low
);
679 code
= build_vec_init (sub
, max
, value
, false, 0,
680 tf_warning_or_error
);
682 if (tree_fits_shwi_p (max
))
683 num_split_elts
+= tree_to_shwi (max
);
688 sub
= build4 (ARRAY_REF
, inner_type
, dest
, field_index
,
689 NULL_TREE
, NULL_TREE
);
691 sub
= build3 (COMPONENT_REF
, inner_type
, dest
, field_index
,
694 code
= build2 (INIT_EXPR
, inner_type
, sub
, value
);
695 code
= build_stmt (input_location
, EXPR_STMT
, code
);
696 code
= maybe_cleanup_point_expr_void (code
);
699 = cxx_maybe_build_cleanup (sub
, tf_warning_or_error
))
700 finish_eh_cleanup (cleanup
);
709 if (!initializer_constant_valid_p (init
, type
))
712 tree cons
= copy_node (init
);
713 CONSTRUCTOR_ELTS (init
) = NULL
;
714 code
= build2 (MODIFY_EXPR
, type
, dest
, cons
);
715 code
= build_stmt (input_location
, EXPR_STMT
, code
);
717 num_split_elts
+= CONSTRUCTOR_NELTS (init
);
725 /* The rest of the initializer is now a constant. */
726 TREE_CONSTANT (init
) = 1;
727 return complete_p
&& complete_ctor_at_level_p (TREE_TYPE (init
),
728 num_split_elts
, inner_type
);
731 /* A subroutine of store_init_value. Splits non-constant static
732 initializer INIT into a constant part and generates code to
733 perform the non-constant part of the initialization to DEST.
734 Returns the code for the runtime init. */
737 split_nonconstant_init (tree dest
, tree init
)
741 if (TREE_CODE (init
) == TARGET_EXPR
)
742 init
= TARGET_EXPR_INITIAL (init
);
743 if (TREE_CODE (init
) == CONSTRUCTOR
)
745 init
= cp_fully_fold (init
);
746 code
= push_stmt_list ();
747 if (split_nonconstant_init_1 (dest
, init
))
749 code
= pop_stmt_list (code
);
750 DECL_INITIAL (dest
) = init
;
751 TREE_READONLY (dest
) = 0;
753 else if (TREE_CODE (init
) == STRING_CST
754 && array_of_runtime_bound_p (TREE_TYPE (dest
)))
755 code
= build_vec_init (dest
, NULL_TREE
, init
, /*value-init*/false,
756 /*from array*/1, tf_warning_or_error
);
758 code
= build2 (INIT_EXPR
, TREE_TYPE (dest
), dest
, init
);
763 /* Perform appropriate conversions on the initial value of a variable,
764 store it in the declaration DECL,
765 and print any error messages that are appropriate.
766 If the init is invalid, store an ERROR_MARK.
768 C++: Note that INIT might be a TREE_LIST, which would mean that it is
769 a base class initializer for some aggregate type, hopefully compatible
770 with DECL. If INIT is a single element, and DECL is an aggregate
771 type, we silently convert INIT into a TREE_LIST, allowing a constructor
774 If INIT is a TREE_LIST and there is no constructor, turn INIT
775 into a CONSTRUCTOR and use standard initialization techniques.
776 Perhaps a warning should be generated?
778 Returns code to be executed if initialization could not be performed
779 for static variable. In that case, caller must emit the code. */
782 store_init_value (tree decl
, tree init
, vec
<tree
, va_gc
>** cleanups
, int flags
)
786 /* If variable's type was invalidly declared, just ignore it. */
788 type
= TREE_TYPE (decl
);
789 if (TREE_CODE (type
) == ERROR_MARK
)
792 if (MAYBE_CLASS_TYPE_P (type
))
794 if (TREE_CODE (init
) == TREE_LIST
)
796 error ("constructor syntax used, but no constructor declared "
797 "for type %qT", type
);
798 init
= build_constructor_from_list (init_list_type_node
, nreverse (init
));
802 /* End of special C++ code. */
804 if (flags
& LOOKUP_ALREADY_DIGESTED
)
807 /* Digest the specified initializer into an expression. */
808 value
= digest_init_flags (type
, init
, flags
, tf_warning_or_error
);
810 value
= extend_ref_init_temps (decl
, value
, cleanups
);
812 /* In C++11 constant expression is a semantic, not syntactic, property.
813 In C++98, make sure that what we thought was a constant expression at
814 template definition time is still constant and otherwise perform this
815 as optimization, e.g. to fold SIZEOF_EXPRs in the initializer. */
816 if (decl_maybe_constant_var_p (decl
) || TREE_STATIC (decl
))
819 value
= instantiate_non_dependent_expr (value
);
820 if (DECL_DECLARED_CONSTEXPR_P (decl
)
821 || (DECL_IN_AGGR_P (decl
) && !DECL_VAR_DECLARED_INLINE_P (decl
)))
823 /* Diagnose a non-constant initializer for constexpr. */
824 if (!require_constant_expression (value
))
825 value
= error_mark_node
;
827 value
= cxx_constant_value (value
, decl
);
829 value
= maybe_constant_init (value
, decl
);
830 if (TREE_CODE (value
) == CONSTRUCTOR
&& cp_has_mutable_p (type
))
831 /* Poison this CONSTRUCTOR so it can't be copied to another
832 constexpr variable. */
833 CONSTRUCTOR_MUTABLE_POISON (value
) = true;
834 const_init
= (reduced_constant_expression_p (value
)
835 || error_operand_p (value
));
836 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl
) = const_init
;
837 /* FIXME setting TREE_CONSTANT on refs breaks the back end. */
838 if (TREE_CODE (type
) != REFERENCE_TYPE
)
839 TREE_CONSTANT (decl
) = const_init
&& decl_maybe_constant_var_p (decl
);
841 value
= cp_fully_fold (value
);
843 /* Handle aggregate NSDMI in non-constant initializers, too. */
844 value
= replace_placeholders (value
, decl
);
846 /* DECL may change value; purge caches. */
847 clear_cv_and_fold_caches ();
849 /* If the initializer is not a constant, fill in DECL_INITIAL with
850 the bits that are constant, and then return an expression that
851 will perform the dynamic initialization. */
852 if (value
!= error_mark_node
853 && (TREE_SIDE_EFFECTS (value
)
854 || array_of_runtime_bound_p (type
)
855 || ! reduced_constant_expression_p (value
)))
856 return split_nonconstant_init (decl
, value
);
857 /* If the value is a constant, just put it in DECL_INITIAL. If DECL
858 is an automatic variable, the middle end will turn this into a
859 dynamic initialization later. */
860 DECL_INITIAL (decl
) = value
;
865 /* Give diagnostic about narrowing conversions within { }. */
868 check_narrowing (tree type
, tree init
, tsubst_flags_t complain
)
870 tree ftype
= unlowered_expr_type (init
);
874 if (((!warn_narrowing
|| !(complain
& tf_warning
))
875 && cxx_dialect
== cxx98
)
876 || !ARITHMETIC_TYPE_P (type
))
879 if (BRACE_ENCLOSED_INITIALIZER_P (init
)
880 && TREE_CODE (type
) == COMPLEX_TYPE
)
882 tree elttype
= TREE_TYPE (type
);
883 if (CONSTRUCTOR_NELTS (init
) > 0)
884 ok
&= check_narrowing (elttype
, CONSTRUCTOR_ELT (init
, 0)->value
,
886 if (CONSTRUCTOR_NELTS (init
) > 1)
887 ok
&= check_narrowing (elttype
, CONSTRUCTOR_ELT (init
, 1)->value
,
892 init
= fold_non_dependent_expr (init
);
894 if (TREE_CODE (type
) == INTEGER_TYPE
895 && TREE_CODE (ftype
) == REAL_TYPE
)
897 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (ftype
)
898 && CP_INTEGRAL_TYPE_P (type
))
900 if (TREE_CODE (ftype
) == ENUMERAL_TYPE
)
901 /* Check for narrowing based on the values of the enumeration. */
902 ftype
= ENUM_UNDERLYING_TYPE (ftype
);
903 if ((tree_int_cst_lt (TYPE_MAX_VALUE (type
),
904 TYPE_MAX_VALUE (ftype
))
905 || tree_int_cst_lt (TYPE_MIN_VALUE (ftype
),
906 TYPE_MIN_VALUE (type
)))
907 && (TREE_CODE (init
) != INTEGER_CST
908 || !int_fits_type_p (init
, type
)))
911 else if (TREE_CODE (ftype
) == REAL_TYPE
912 && TREE_CODE (type
) == REAL_TYPE
)
914 if (TYPE_PRECISION (type
) < TYPE_PRECISION (ftype
))
916 if (TREE_CODE (init
) == REAL_CST
)
918 /* Issue 703: Loss of precision is OK as long as the value is
919 within the representable range of the new type. */
921 d
= TREE_REAL_CST (init
);
922 real_convert (&r
, TYPE_MODE (type
), &d
);
930 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (ftype
)
931 && TREE_CODE (type
) == REAL_TYPE
)
934 if (TREE_CODE (init
) == INTEGER_CST
)
936 d
= real_value_from_int_cst (0, init
);
937 if (exact_real_truncate (TYPE_MODE (type
), &d
))
943 if (!ok
&& !CONSTANT_CLASS_P (init
) && (complain
& tf_warning_or_error
))
945 tree folded
= cp_fully_fold (init
);
946 if (TREE_CONSTANT (folded
) && check_narrowing (type
, folded
, tf_none
))
952 location_t loc
= EXPR_LOC_OR_LOC (init
, input_location
);
953 if (cxx_dialect
== cxx98
)
955 if (complain
& tf_warning
)
956 warning_at (loc
, OPT_Wnarrowing
, "narrowing conversion of %qE "
957 "from %qH to %qI inside { } is ill-formed in C++11",
961 else if (!CONSTANT_CLASS_P (init
))
963 if (complain
& tf_warning_or_error
)
965 if ((!almost_ok
|| pedantic
)
966 && pedwarn (loc
, OPT_Wnarrowing
,
967 "narrowing conversion of %qE "
968 "from %qH to %qI inside { }",
971 inform (loc
, " the expression has a constant value but is not "
972 "a C++ constant-expression");
976 else if (complain
& tf_error
)
978 int savederrorcount
= errorcount
;
979 global_dc
->pedantic_errors
= 1;
980 pedwarn (loc
, OPT_Wnarrowing
,
981 "narrowing conversion of %qE from %qH to %qI "
982 "inside { }", init
, ftype
, type
);
983 if (errorcount
== savederrorcount
)
985 global_dc
->pedantic_errors
= flag_pedantic_errors
;
992 /* Process the initializer INIT for a variable of type TYPE, emitting
993 diagnostics for invalid initializers and converting the initializer as
996 For aggregate types, it assumes that reshape_init has already run, thus the
997 initializer will have the right shape (brace elision has been undone).
999 NESTED is true iff we are being called for an element of a CONSTRUCTOR. */
1002 digest_init_r (tree type
, tree init
, bool nested
, int flags
,
1003 tsubst_flags_t complain
)
1005 enum tree_code code
= TREE_CODE (type
);
1007 if (error_operand_p (init
))
1008 return error_mark_node
;
1012 /* We must strip the outermost array type when completing the type,
1013 because the its bounds might be incomplete at the moment. */
1014 if (!complete_type_or_maybe_complain (TREE_CODE (type
) == ARRAY_TYPE
1015 ? TREE_TYPE (type
) : type
, NULL_TREE
,
1017 return error_mark_node
;
1019 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue
1020 (g++.old-deja/g++.law/casts2.C). */
1021 if (TREE_CODE (init
) == NON_LVALUE_EXPR
)
1022 init
= TREE_OPERAND (init
, 0);
1024 location_t loc
= EXPR_LOC_OR_LOC (init
, input_location
);
1026 /* Initialization of an array of chars from a string constant. The initializer
1027 can be optionally enclosed in braces, but reshape_init has already removed
1028 them if they were present. */
1029 if (code
== ARRAY_TYPE
)
1031 if (nested
&& !TYPE_DOMAIN (type
))
1033 /* C++ flexible array members have a null domain. */
1034 pedwarn (loc
, OPT_Wpedantic
,
1035 "initialization of a flexible array member");
1038 tree typ1
= TYPE_MAIN_VARIANT (TREE_TYPE (type
));
1039 if (char_type_p (typ1
)
1041 && TREE_CODE (init
) == STRING_CST
)
1043 tree char_type
= TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (init
)));
1045 if (TYPE_PRECISION (typ1
) == BITS_PER_UNIT
)
1047 if (char_type
!= char_type_node
)
1049 if (complain
& tf_error
)
1050 error_at (loc
, "char-array initialized from wide string");
1051 return error_mark_node
;
1056 if (char_type
== char_type_node
)
1058 if (complain
& tf_error
)
1060 "int-array initialized from non-wide string");
1061 return error_mark_node
;
1063 else if (char_type
!= typ1
)
1065 if (complain
& tf_error
)
1066 error_at (loc
, "int-array initialized from incompatible "
1068 return error_mark_node
;
1072 if (type
!= TREE_TYPE (init
)
1073 && !variably_modified_type_p (type
, NULL_TREE
))
1075 init
= copy_node (init
);
1076 TREE_TYPE (init
) = type
;
1078 if (TYPE_DOMAIN (type
) && TREE_CONSTANT (TYPE_SIZE (type
)))
1080 /* Not a flexible array member. */
1081 int size
= TREE_INT_CST_LOW (TYPE_SIZE (type
));
1082 size
= (size
+ BITS_PER_UNIT
- 1) / BITS_PER_UNIT
;
1083 /* In C it is ok to subtract 1 from the length of the string
1084 because it's ok to ignore the terminating null char that is
1085 counted in the length of the constant, but in C++ this would
1087 if (size
< TREE_STRING_LENGTH (init
))
1088 permerror (loc
, "initializer-string for array "
1089 "of chars is too long");
1095 /* Handle scalar types (including conversions) and references. */
1096 if ((TREE_CODE (type
) != COMPLEX_TYPE
1097 || BRACE_ENCLOSED_INITIALIZER_P (init
))
1098 && (SCALAR_TYPE_P (type
) || code
== REFERENCE_TYPE
))
1101 flags
|= LOOKUP_NO_NARROWING
;
1102 init
= convert_for_initialization (0, type
, init
, flags
,
1103 ICR_INIT
, NULL_TREE
, 0,
1109 /* Come here only for aggregates: records, arrays, unions, complex numbers
1111 gcc_assert (TREE_CODE (type
) == ARRAY_TYPE
1112 || VECTOR_TYPE_P (type
)
1113 || TREE_CODE (type
) == RECORD_TYPE
1114 || TREE_CODE (type
) == UNION_TYPE
1115 || TREE_CODE (type
) == COMPLEX_TYPE
);
1117 /* "If T is a class type and the initializer list has a single
1118 element of type cv U, where U is T or a class derived from T,
1119 the object is initialized from that element." */
1121 && cxx_dialect
>= cxx11
1122 && BRACE_ENCLOSED_INITIALIZER_P (init
)
1123 && CONSTRUCTOR_NELTS (init
) == 1
1124 && ((CLASS_TYPE_P (type
) && !CLASSTYPE_NON_AGGREGATE (type
))
1125 || VECTOR_TYPE_P (type
)))
1127 tree elt
= CONSTRUCTOR_ELT (init
, 0)->value
;
1128 if (reference_related_p (type
, TREE_TYPE (elt
)))
1129 /* We should have fixed this in reshape_init. */
1133 if (BRACE_ENCLOSED_INITIALIZER_P (init
)
1134 && !TYPE_NON_AGGREGATE_CLASS (type
))
1135 return process_init_constructor (type
, init
, complain
);
1138 if (COMPOUND_LITERAL_P (init
) && TREE_CODE (type
) == ARRAY_TYPE
)
1140 if (complain
& tf_error
)
1141 error_at (loc
, "cannot initialize aggregate of type %qT with "
1142 "a compound literal", type
);
1144 return error_mark_node
;
1147 if (TREE_CODE (type
) == ARRAY_TYPE
1148 && !BRACE_ENCLOSED_INITIALIZER_P (init
))
1150 /* Allow the result of build_array_copy and of
1151 build_value_init_noctor. */
1152 if ((TREE_CODE (init
) == VEC_INIT_EXPR
1153 || TREE_CODE (init
) == CONSTRUCTOR
)
1154 && (same_type_ignoring_top_level_qualifiers_p
1155 (type
, TREE_TYPE (init
))))
1158 if (complain
& tf_error
)
1159 error_at (loc
, "array must be initialized with a brace-enclosed"
1161 return error_mark_node
;
1164 return convert_for_initialization (NULL_TREE
, type
, init
,
1166 ICR_INIT
, NULL_TREE
, 0,
1172 digest_init (tree type
, tree init
, tsubst_flags_t complain
)
1174 return digest_init_r (type
, init
, false, LOOKUP_IMPLICIT
, complain
);
1178 digest_init_flags (tree type
, tree init
, int flags
, tsubst_flags_t complain
)
1180 return digest_init_r (type
, init
, false, flags
, complain
);
1183 /* Process the initializer INIT for an NSDMI DECL (a FIELD_DECL). */
1185 digest_nsdmi_init (tree decl
, tree init
, tsubst_flags_t complain
)
1187 gcc_assert (TREE_CODE (decl
) == FIELD_DECL
);
1189 tree type
= TREE_TYPE (decl
);
1190 int flags
= LOOKUP_IMPLICIT
;
1191 if (DIRECT_LIST_INIT_P (init
))
1192 flags
= LOOKUP_NORMAL
;
1193 if (BRACE_ENCLOSED_INITIALIZER_P (init
)
1194 && CP_AGGREGATE_TYPE_P (type
))
1195 init
= reshape_init (type
, init
, complain
);
1196 init
= digest_init_flags (type
, init
, flags
, complain
);
1197 if (TREE_CODE (init
) == TARGET_EXPR
)
1198 /* This represents the whole initialization. */
1199 TARGET_EXPR_DIRECT_INIT_P (init
) = true;
1203 /* Set of flags used within process_init_constructor to describe the
1205 #define PICFLAG_ERRONEOUS 1
1206 #define PICFLAG_NOT_ALL_CONSTANT 2
1207 #define PICFLAG_NOT_ALL_SIMPLE 4
1208 #define PICFLAG_SIDE_EFFECTS 8
1210 /* Given an initializer INIT, return the flag (PICFLAG_*) which better
1214 picflag_from_initializer (tree init
)
1216 if (init
== error_mark_node
)
1217 return PICFLAG_ERRONEOUS
;
1218 else if (!TREE_CONSTANT (init
))
1220 if (TREE_SIDE_EFFECTS (init
))
1221 return PICFLAG_SIDE_EFFECTS
;
1223 return PICFLAG_NOT_ALL_CONSTANT
;
1225 else if (!initializer_constant_valid_p (init
, TREE_TYPE (init
)))
1226 return PICFLAG_NOT_ALL_SIMPLE
;
1230 /* Adjust INIT for going into a CONSTRUCTOR. */
1233 massage_init_elt (tree type
, tree init
, tsubst_flags_t complain
)
1235 init
= digest_init_r (type
, init
, true, LOOKUP_IMPLICIT
, complain
);
1236 /* Strip a simple TARGET_EXPR when we know this is an initializer. */
1237 if (SIMPLE_TARGET_EXPR_P (init
))
1238 init
= TARGET_EXPR_INITIAL (init
);
1239 /* When we defer constant folding within a statement, we may want to
1240 defer this folding as well. */
1241 tree t
= fold_non_dependent_expr (init
);
1242 t
= maybe_constant_init (t
);
1243 if (TREE_CONSTANT (t
))
1248 /* Subroutine of process_init_constructor, which will process an initializer
1249 INIT for an array or vector of type TYPE. Returns the flags (PICFLAG_*)
1250 which describe the initializers. */
1253 process_init_constructor_array (tree type
, tree init
,
1254 tsubst_flags_t complain
)
1256 unsigned HOST_WIDE_INT i
, len
= 0;
1258 bool unbounded
= false;
1259 constructor_elt
*ce
;
1260 vec
<constructor_elt
, va_gc
> *v
= CONSTRUCTOR_ELTS (init
);
1262 gcc_assert (TREE_CODE (type
) == ARRAY_TYPE
1263 || VECTOR_TYPE_P (type
));
1265 if (TREE_CODE (type
) == ARRAY_TYPE
)
1267 /* C++ flexible array members have a null domain. */
1268 tree domain
= TYPE_DOMAIN (type
);
1269 if (domain
&& TREE_CONSTANT (TYPE_MAX_VALUE (domain
)))
1270 len
= wi::ext (wi::to_offset (TYPE_MAX_VALUE (domain
))
1271 - wi::to_offset (TYPE_MIN_VALUE (domain
)) + 1,
1272 TYPE_PRECISION (TREE_TYPE (domain
)),
1273 TYPE_SIGN (TREE_TYPE (domain
))).to_uhwi ();
1275 unbounded
= true; /* Take as many as there are. */
1278 /* Vectors are like simple fixed-size arrays. */
1279 len
= TYPE_VECTOR_SUBPARTS (type
);
1281 /* There must not be more initializers than needed. */
1282 if (!unbounded
&& vec_safe_length (v
) > len
)
1284 if (complain
& tf_error
)
1285 error ("too many initializers for %qT", type
);
1287 return PICFLAG_ERRONEOUS
;
1290 FOR_EACH_VEC_SAFE_ELT (v
, i
, ce
)
1294 gcc_assert (TREE_CODE (ce
->index
) == INTEGER_CST
);
1295 if (compare_tree_int (ce
->index
, i
) != 0)
1297 ce
->value
= error_mark_node
;
1298 sorry ("non-trivial designated initializers not supported");
1302 ce
->index
= size_int (i
);
1303 gcc_assert (ce
->value
);
1304 ce
->value
= massage_init_elt (TREE_TYPE (type
), ce
->value
, complain
);
1306 if (ce
->value
!= error_mark_node
)
1307 gcc_assert (same_type_ignoring_top_level_qualifiers_p
1308 (TREE_TYPE (type
), TREE_TYPE (ce
->value
)));
1310 flags
|= picflag_from_initializer (ce
->value
);
1313 /* No more initializers. If the array is unbounded, we are done. Otherwise,
1314 we must add initializers ourselves. */
1316 for (; i
< len
; ++i
)
1320 if (type_build_ctor_call (TREE_TYPE (type
)))
1322 /* If this type needs constructors run for default-initialization,
1323 we can't rely on the back end to do it for us, so make the
1324 initialization explicit by list-initializing from T{}. */
1325 next
= build_constructor (init_list_type_node
, NULL
);
1326 next
= massage_init_elt (TREE_TYPE (type
), next
, complain
);
1327 if (initializer_zerop (next
))
1328 /* The default zero-initialization is fine for us; don't
1329 add anything to the CONSTRUCTOR. */
1332 else if (!zero_init_p (TREE_TYPE (type
)))
1333 next
= build_zero_init (TREE_TYPE (type
),
1334 /*nelts=*/NULL_TREE
,
1335 /*static_storage_p=*/false);
1337 /* The default zero-initialization is fine for us; don't
1338 add anything to the CONSTRUCTOR. */
1343 flags
|= picflag_from_initializer (next
);
1344 CONSTRUCTOR_APPEND_ELT (v
, size_int (i
), next
);
1348 CONSTRUCTOR_ELTS (init
) = v
;
1352 /* Subroutine of process_init_constructor, which will process an initializer
1353 INIT for a class of type TYPE. Returns the flags (PICFLAG_*) which describe
1354 the initializers. */
1357 process_init_constructor_record (tree type
, tree init
,
1358 tsubst_flags_t complain
)
1360 vec
<constructor_elt
, va_gc
> *v
= NULL
;
1364 gcc_assert (TREE_CODE (type
) == RECORD_TYPE
);
1365 gcc_assert (!CLASSTYPE_VBASECLASSES (type
));
1366 gcc_assert (!TYPE_BINFO (type
)
1367 || cxx_dialect
>= cxx17
1368 || !BINFO_N_BASE_BINFOS (TYPE_BINFO (type
)));
1369 gcc_assert (!TYPE_POLYMORPHIC_P (type
));
1373 unsigned HOST_WIDE_INT idx
= 0;
1374 int designator_skip
= -1;
1375 /* Generally, we will always have an index for each initializer (which is
1376 a FIELD_DECL, put by reshape_init), but compound literals don't go trough
1377 reshape_init. So we need to handle both cases. */
1378 for (field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
1383 if (!DECL_NAME (field
) && DECL_C_BIT_FIELD (field
))
1386 if (TREE_CODE (field
) != FIELD_DECL
1387 || (DECL_ARTIFICIAL (field
)
1388 && !(cxx_dialect
>= cxx17
&& DECL_FIELD_IS_BASE (field
))))
1391 /* If this is a bitfield, first convert to the declared type. */
1392 type
= TREE_TYPE (field
);
1393 if (DECL_BIT_FIELD_TYPE (field
))
1394 type
= DECL_BIT_FIELD_TYPE (field
);
1395 if (type
== error_mark_node
)
1396 return PICFLAG_ERRONEOUS
;
1399 if (idx
< CONSTRUCTOR_NELTS (init
))
1401 constructor_elt
*ce
= &(*CONSTRUCTOR_ELTS (init
))[idx
];
1404 /* We can have either a FIELD_DECL or an IDENTIFIER_NODE. The
1405 latter case can happen in templates where lookup has to be
1407 gcc_assert (TREE_CODE (ce
->index
) == FIELD_DECL
1408 || identifier_p (ce
->index
));
1409 if (ce
->index
== field
|| ce
->index
== DECL_NAME (field
))
1411 else if (ANON_AGGR_TYPE_P (type
)
1412 && search_anon_aggr (type
,
1413 TREE_CODE (ce
->index
) == FIELD_DECL
1414 ? DECL_NAME (ce
->index
)
1416 /* If the element is an anonymous union object and the
1417 initializer list is a designated-initializer-list, the
1418 anonymous union object is initialized by the
1419 designated-initializer-list { D }, where D is the
1420 designated-initializer-clause naming a member of the
1421 anonymous union object. */
1422 next
= build_constructor_single (type
, ce
->index
, ce
->value
);
1426 if (designator_skip
== -1)
1427 designator_skip
= 1;
1432 designator_skip
= 0;
1438 gcc_assert (ce
->value
);
1439 next
= massage_init_elt (type
, next
, complain
);
1444 /* Already handled above. */;
1445 else if (DECL_INITIAL (field
))
1449 /* We're using an NSDMI past a field with implicit
1450 zero-init. Go back and make it explicit. */
1452 vec_safe_truncate (v
, 0);
1455 /* C++14 aggregate NSDMI. */
1456 next
= get_nsdmi (field
, /*ctor*/false, complain
);
1458 else if (type_build_ctor_call (TREE_TYPE (field
)))
1460 /* If this type needs constructors run for
1461 default-initialization, we can't rely on the back end to do it
1462 for us, so build up TARGET_EXPRs. If the type in question is
1463 a class, just build one up; if it's an array, recurse. */
1464 next
= build_constructor (init_list_type_node
, NULL
);
1465 next
= massage_init_elt (TREE_TYPE (field
), next
, complain
);
1467 /* Warn when some struct elements are implicitly initialized. */
1468 if ((complain
& tf_warning
)
1469 && !EMPTY_CONSTRUCTOR_P (init
))
1470 warning (OPT_Wmissing_field_initializers
,
1471 "missing initializer for member %qD", field
);
1475 const_tree fldtype
= TREE_TYPE (field
);
1476 if (TREE_CODE (fldtype
) == REFERENCE_TYPE
)
1478 if (complain
& tf_error
)
1479 error ("member %qD is uninitialized reference", field
);
1481 return PICFLAG_ERRONEOUS
;
1483 else if (CLASSTYPE_REF_FIELDS_NEED_INIT (fldtype
))
1485 if (complain
& tf_error
)
1486 error ("member %qD with uninitialized reference fields", field
);
1488 return PICFLAG_ERRONEOUS
;
1491 /* Warn when some struct elements are implicitly initialized
1492 to zero. However, avoid issuing the warning for flexible
1493 array members since they need not have any elements. */
1494 if ((TREE_CODE (fldtype
) != ARRAY_TYPE
|| TYPE_DOMAIN (fldtype
))
1495 && (complain
& tf_warning
)
1496 && !EMPTY_CONSTRUCTOR_P (init
))
1497 warning (OPT_Wmissing_field_initializers
,
1498 "missing initializer for member %qD", field
);
1500 if (!zero_init_p (fldtype
)
1502 next
= build_zero_init (TREE_TYPE (field
), /*nelts=*/NULL_TREE
,
1503 /*static_storage_p=*/false);
1506 /* The default zero-initialization is fine for us; don't
1507 add anything to the CONSTRUCTOR. */
1513 /* If this is a bitfield, now convert to the lowered type. */
1514 if (type
!= TREE_TYPE (field
))
1515 next
= cp_convert_and_check (TREE_TYPE (field
), next
, complain
);
1516 flags
|= picflag_from_initializer (next
);
1517 CONSTRUCTOR_APPEND_ELT (v
, field
, next
);
1520 if (idx
< CONSTRUCTOR_NELTS (init
))
1522 if (complain
& tf_error
)
1524 constructor_elt
*ce
= &(*CONSTRUCTOR_ELTS (init
))[idx
];
1525 /* For better diagnostics, try to find out if it is really
1526 the case of too many initializers or if designators are
1527 in incorrect order. */
1528 if (designator_skip
== 1 && ce
->index
)
1530 gcc_assert (TREE_CODE (ce
->index
) == FIELD_DECL
1531 || identifier_p (ce
->index
));
1532 for (field
= TYPE_FIELDS (type
);
1533 field
; field
= DECL_CHAIN (field
))
1535 if (!DECL_NAME (field
) && DECL_C_BIT_FIELD (field
))
1537 if (TREE_CODE (field
) != FIELD_DECL
1538 || (DECL_ARTIFICIAL (field
)
1539 && !(cxx_dialect
>= cxx17
1540 && DECL_FIELD_IS_BASE (field
))))
1543 if (ce
->index
== field
|| ce
->index
== DECL_NAME (field
))
1545 if (ANON_AGGR_TYPE_P (TREE_TYPE (field
)))
1548 = search_anon_aggr (TREE_TYPE (field
),
1549 TREE_CODE (ce
->index
) == FIELD_DECL
1550 ? DECL_NAME (ce
->index
)
1561 error ("designator order for field %qD does not match declaration "
1562 "order in %qT", field
, type
);
1564 error ("too many initializers for %qT", type
);
1567 return PICFLAG_ERRONEOUS
;
1570 CONSTRUCTOR_ELTS (init
) = v
;
1574 /* Subroutine of process_init_constructor, which will process a single
1575 initializer INIT for a union of type TYPE. Returns the flags (PICFLAG_*)
1576 which describe the initializer. */
1579 process_init_constructor_union (tree type
, tree init
,
1580 tsubst_flags_t complain
)
1582 constructor_elt
*ce
;
1585 /* If the initializer was empty, use the union's NSDMI if it has one.
1586 Otherwise use default zero initialization. */
1587 if (vec_safe_is_empty (CONSTRUCTOR_ELTS (init
)))
1589 for (tree field
= TYPE_FIELDS (type
); field
; field
= TREE_CHAIN (field
))
1591 if (TREE_CODE (field
) == FIELD_DECL
1592 && DECL_INITIAL (field
) != NULL_TREE
)
1594 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (init
),
1596 get_nsdmi (field
, /*in_ctor=*/false,
1602 if (vec_safe_is_empty (CONSTRUCTOR_ELTS (init
)))
1606 len
= CONSTRUCTOR_ELTS (init
)->length ();
1609 if (!(complain
& tf_error
))
1610 return PICFLAG_ERRONEOUS
;
1611 error ("too many initializers for %qT", type
);
1612 CONSTRUCTOR_ELTS (init
)->block_remove (1, len
-1);
1615 ce
= &(*CONSTRUCTOR_ELTS (init
))[0];
1617 /* If this element specifies a field, initialize via that field. */
1620 if (TREE_CODE (ce
->index
) == FIELD_DECL
)
1622 else if (identifier_p (ce
->index
))
1624 /* This can happen within a cast, see g++.dg/opt/cse2.C. */
1625 tree name
= ce
->index
;
1627 for (field
= TYPE_FIELDS (type
); field
; field
= TREE_CHAIN (field
))
1628 if (DECL_NAME (field
) == name
)
1632 if (complain
& tf_error
)
1633 error ("no field %qD found in union being initialized",
1635 ce
->value
= error_mark_node
;
1641 gcc_assert (TREE_CODE (ce
->index
) == INTEGER_CST
1642 || TREE_CODE (ce
->index
) == RANGE_EXPR
);
1643 if (complain
& tf_error
)
1644 error ("index value instead of field name in union initializer");
1645 ce
->value
= error_mark_node
;
1650 /* Find the first named field. ANSI decided in September 1990
1651 that only named fields count here. */
1652 tree field
= TYPE_FIELDS (type
);
1653 while (field
&& (!DECL_NAME (field
) || TREE_CODE (field
) != FIELD_DECL
))
1654 field
= TREE_CHAIN (field
);
1655 if (field
== NULL_TREE
)
1657 if (complain
& tf_error
)
1658 error ("too many initializers for %qT", type
);
1659 ce
->value
= error_mark_node
;
1664 if (ce
->value
&& ce
->value
!= error_mark_node
)
1665 ce
->value
= massage_init_elt (TREE_TYPE (ce
->index
), ce
->value
, complain
);
1667 return picflag_from_initializer (ce
->value
);
1670 /* Process INIT, a constructor for a variable of aggregate type TYPE. The
1671 constructor is a brace-enclosed initializer, and will be modified in-place.
1673 Each element is converted to the right type through digest_init, and
1674 missing initializers are added following the language rules (zero-padding,
1677 After the execution, the initializer will have TREE_CONSTANT if all elts are
1678 constant, and TREE_STATIC set if, in addition, all elts are simple enough
1679 constants that the assembler and linker can compute them.
1681 The function returns the initializer itself, or error_mark_node in case
1685 process_init_constructor (tree type
, tree init
, tsubst_flags_t complain
)
1689 gcc_assert (BRACE_ENCLOSED_INITIALIZER_P (init
));
1691 if (TREE_CODE (type
) == ARRAY_TYPE
|| VECTOR_TYPE_P (type
))
1692 flags
= process_init_constructor_array (type
, init
, complain
);
1693 else if (TREE_CODE (type
) == RECORD_TYPE
)
1694 flags
= process_init_constructor_record (type
, init
, complain
);
1695 else if (TREE_CODE (type
) == UNION_TYPE
)
1696 flags
= process_init_constructor_union (type
, init
, complain
);
1700 if (flags
& PICFLAG_ERRONEOUS
)
1701 return error_mark_node
;
1703 TREE_TYPE (init
) = type
;
1704 if (TREE_CODE (type
) == ARRAY_TYPE
&& TYPE_DOMAIN (type
) == NULL_TREE
)
1705 cp_complete_array_type (&TREE_TYPE (init
), init
, /*do_default=*/0);
1706 if (flags
& PICFLAG_SIDE_EFFECTS
)
1708 TREE_CONSTANT (init
) = false;
1709 TREE_SIDE_EFFECTS (init
) = true;
1711 else if (flags
& PICFLAG_NOT_ALL_CONSTANT
)
1712 /* Make sure TREE_CONSTANT isn't set from build_constructor. */
1713 TREE_CONSTANT (init
) = false;
1716 TREE_CONSTANT (init
) = 1;
1717 if (!(flags
& PICFLAG_NOT_ALL_SIMPLE
))
1718 TREE_STATIC (init
) = 1;
1723 /* Given a structure or union value DATUM, construct and return
1724 the structure or union component which results from narrowing
1725 that value to the base specified in BASETYPE. For example, given the
1728 class L { int ii; };
1729 class A : L { ... };
1730 class B : L { ... };
1731 class C : A, B { ... };
1739 x.A::ii refers to the ii member of the L part of
1740 the A part of the C object named by X. In this case,
1741 DATUM would be x, and BASETYPE would be A.
1743 I used to think that this was nonconformant, that the standard specified
1744 that first we look up ii in A, then convert x to an L& and pull out the
1745 ii part. But in fact, it does say that we convert x to an A&; A here
1746 is known as the "naming class". (jason 2000-12-19)
1748 BINFO_P points to a variable initialized either to NULL_TREE or to the
1749 binfo for the specific base subobject we want to convert to. */
1752 build_scoped_ref (tree datum
, tree basetype
, tree
* binfo_p
)
1756 if (datum
== error_mark_node
)
1757 return error_mark_node
;
1761 binfo
= lookup_base (TREE_TYPE (datum
), basetype
, ba_check
,
1762 NULL
, tf_warning_or_error
);
1764 if (!binfo
|| binfo
== error_mark_node
)
1766 *binfo_p
= NULL_TREE
;
1768 error_not_base_type (basetype
, TREE_TYPE (datum
));
1769 return error_mark_node
;
1773 return build_base_path (PLUS_EXPR
, datum
, binfo
, 1,
1774 tf_warning_or_error
);
1777 /* Build a reference to an object specified by the C++ `->' operator.
1778 Usually this just involves dereferencing the object, but if the
1779 `->' operator is overloaded, then such overloads must be
1780 performed until an object which does not have the `->' operator
1781 overloaded is found. An error is reported when circular pointer
1782 delegation is detected. */
1785 build_x_arrow (location_t loc
, tree expr
, tsubst_flags_t complain
)
1787 tree orig_expr
= expr
;
1788 tree type
= TREE_TYPE (expr
);
1789 tree last_rval
= NULL_TREE
;
1790 vec
<tree
, va_gc
> *types_memoized
= NULL
;
1792 if (type
== error_mark_node
)
1793 return error_mark_node
;
1795 if (processing_template_decl
)
1797 if (type
&& TREE_CODE (type
) == POINTER_TYPE
1798 && !dependent_scope_p (TREE_TYPE (type
)))
1799 /* Pointer to current instantiation, don't treat as dependent. */;
1800 else if (type_dependent_expression_p (expr
))
1801 return build_min_nt_loc (loc
, ARROW_EXPR
, expr
);
1802 expr
= build_non_dependent_expr (expr
);
1805 if (MAYBE_CLASS_TYPE_P (type
))
1807 struct tinst_level
*actual_inst
= current_instantiation ();
1810 while ((expr
= build_new_op (loc
, COMPONENT_REF
,
1811 LOOKUP_NORMAL
, expr
, NULL_TREE
, NULL_TREE
,
1814 if (expr
== error_mark_node
)
1815 return error_mark_node
;
1817 /* This provides a better instantiation backtrace in case of
1819 if (fn
&& DECL_USE_TEMPLATE (fn
))
1820 push_tinst_level_loc (fn
,
1821 (current_instantiation () != actual_inst
)
1822 ? DECL_SOURCE_LOCATION (fn
)
1826 if (vec_member (TREE_TYPE (expr
), types_memoized
))
1828 if (complain
& tf_error
)
1829 error ("circular pointer delegation detected");
1830 return error_mark_node
;
1833 vec_safe_push (types_memoized
, TREE_TYPE (expr
));
1837 while (current_instantiation () != actual_inst
)
1840 if (last_rval
== NULL_TREE
)
1842 if (complain
& tf_error
)
1843 error ("base operand of %<->%> has non-pointer type %qT", type
);
1844 return error_mark_node
;
1847 if (TREE_CODE (TREE_TYPE (last_rval
)) == REFERENCE_TYPE
)
1848 last_rval
= convert_from_reference (last_rval
);
1851 last_rval
= decay_conversion (expr
, complain
);
1853 if (TYPE_PTR_P (TREE_TYPE (last_rval
)))
1855 if (processing_template_decl
)
1857 expr
= build_min (ARROW_EXPR
, TREE_TYPE (TREE_TYPE (last_rval
)),
1859 TREE_SIDE_EFFECTS (expr
) = TREE_SIDE_EFFECTS (last_rval
);
1863 return cp_build_indirect_ref (last_rval
, RO_ARROW
, complain
);
1866 if (complain
& tf_error
)
1869 error ("result of %<operator->()%> yields non-pointer result");
1871 error ("base operand of %<->%> is not a pointer");
1873 return error_mark_node
;
1876 /* Return an expression for "DATUM .* COMPONENT". DATUM has not
1877 already been checked out to be of aggregate type. */
1880 build_m_component_ref (tree datum
, tree component
, tsubst_flags_t complain
)
1888 if (error_operand_p (datum
) || error_operand_p (component
))
1889 return error_mark_node
;
1891 datum
= mark_lvalue_use (datum
);
1892 component
= mark_rvalue_use (component
);
1894 ptrmem_type
= TREE_TYPE (component
);
1895 if (!TYPE_PTRMEM_P (ptrmem_type
))
1897 if (complain
& tf_error
)
1898 error ("%qE cannot be used as a member pointer, since it is of "
1899 "type %qT", component
, ptrmem_type
);
1900 return error_mark_node
;
1903 objtype
= TYPE_MAIN_VARIANT (TREE_TYPE (datum
));
1904 if (! MAYBE_CLASS_TYPE_P (objtype
))
1906 if (complain
& tf_error
)
1907 error ("cannot apply member pointer %qE to %qE, which is of "
1908 "non-class type %qT", component
, datum
, objtype
);
1909 return error_mark_node
;
1912 type
= TYPE_PTRMEM_POINTED_TO_TYPE (ptrmem_type
);
1913 ctype
= complete_type (TYPE_PTRMEM_CLASS_TYPE (ptrmem_type
));
1915 if (!COMPLETE_TYPE_P (ctype
))
1917 if (!same_type_p (ctype
, objtype
))
1923 binfo
= lookup_base (objtype
, ctype
, ba_check
, NULL
, complain
);
1928 if (complain
& tf_error
)
1929 error ("pointer to member type %qT incompatible with object "
1930 "type %qT", type
, objtype
);
1931 return error_mark_node
;
1933 else if (binfo
== error_mark_node
)
1934 return error_mark_node
;
1937 if (TYPE_PTRDATAMEM_P (ptrmem_type
))
1939 cp_lvalue_kind kind
= lvalue_kind (datum
);
1942 /* Compute the type of the field, as described in [expr.ref].
1943 There's no such thing as a mutable pointer-to-member, so
1944 things are not as complex as they are for references to
1945 non-static data members. */
1946 type
= cp_build_qualified_type (type
,
1947 (cp_type_quals (type
)
1948 | cp_type_quals (TREE_TYPE (datum
))));
1950 datum
= build_address (datum
);
1952 /* Convert object to the correct base. */
1955 datum
= build_base_path (PLUS_EXPR
, datum
, binfo
, 1, complain
);
1956 if (datum
== error_mark_node
)
1957 return error_mark_node
;
1960 /* Build an expression for "object + offset" where offset is the
1961 value stored in the pointer-to-data-member. */
1962 ptype
= build_pointer_type (type
);
1963 datum
= fold_build_pointer_plus (fold_convert (ptype
, datum
), component
);
1964 datum
= cp_build_fold_indirect_ref (datum
);
1965 if (datum
== error_mark_node
)
1966 return error_mark_node
;
1968 /* If the object expression was an rvalue, return an rvalue. */
1969 if (kind
& clk_class
)
1970 datum
= rvalue (datum
);
1971 else if (kind
& clk_rvalueref
)
1972 datum
= move (datum
);
1977 /* 5.5/6: In a .* expression whose object expression is an rvalue, the
1978 program is ill-formed if the second operand is a pointer to member
1979 function with ref-qualifier & (for C++2A: unless its cv-qualifier-seq
1980 is const). In a .* expression whose object expression is an lvalue,
1981 the program is ill-formed if the second operand is a pointer to member
1982 function with ref-qualifier &&. */
1983 if (FUNCTION_REF_QUALIFIED (type
))
1985 bool lval
= lvalue_p (datum
);
1986 if (lval
&& FUNCTION_RVALUE_QUALIFIED (type
))
1988 if (complain
& tf_error
)
1989 error ("pointer-to-member-function type %qT requires an rvalue",
1991 return error_mark_node
;
1993 else if (!lval
&& !FUNCTION_RVALUE_QUALIFIED (type
))
1995 if ((type_memfn_quals (type
)
1996 & (TYPE_QUAL_CONST
| TYPE_QUAL_VOLATILE
))
1999 if (complain
& tf_error
)
2000 error ("pointer-to-member-function type %qT requires "
2001 "an lvalue", ptrmem_type
);
2002 return error_mark_node
;
2004 else if (cxx_dialect
< cxx2a
)
2006 if (complain
& tf_warning_or_error
)
2007 pedwarn (input_location
, OPT_Wpedantic
,
2008 "pointer-to-member-function type %qT requires "
2009 "an lvalue before C++2a", ptrmem_type
);
2011 return error_mark_node
;
2015 return build2 (OFFSET_REF
, type
, datum
, component
);
2019 /* Return a tree node for the expression TYPENAME '(' PARMS ')'. */
2022 build_functional_cast (tree exp
, tree parms
, tsubst_flags_t complain
)
2024 /* This is either a call to a constructor,
2025 or a C cast in C++'s `functional' notation. */
2027 /* The type to which we are casting. */
2029 vec
<tree
, va_gc
> *parmvec
;
2031 if (error_operand_p (exp
) || parms
== error_mark_node
)
2032 return error_mark_node
;
2034 if (TREE_CODE (exp
) == TYPE_DECL
)
2036 type
= TREE_TYPE (exp
);
2038 if (complain
& tf_warning
2039 && TREE_DEPRECATED (type
)
2040 && DECL_ARTIFICIAL (exp
))
2041 warn_deprecated_use (type
, NULL_TREE
);
2046 /* We need to check this explicitly, since value-initialization of
2047 arrays is allowed in other situations. */
2048 if (TREE_CODE (type
) == ARRAY_TYPE
)
2050 if (complain
& tf_error
)
2051 error ("functional cast to array type %qT", type
);
2052 return error_mark_node
;
2055 if (tree anode
= type_uses_auto (type
))
2057 if (!CLASS_PLACEHOLDER_TEMPLATE (anode
))
2059 if (complain
& tf_error
)
2060 error ("invalid use of %qT", anode
);
2061 return error_mark_node
;
2065 if (complain
& tf_error
)
2066 error ("cannot deduce template arguments for %qT from ()", anode
);
2067 return error_mark_node
;
2070 type
= do_auto_deduction (type
, parms
, anode
, complain
,
2074 if (processing_template_decl
)
2078 /* Diagnose this even in a template. We could also try harder
2079 to give all the usual errors when the type and args are
2081 if (TREE_CODE (type
) == REFERENCE_TYPE
&& !parms
)
2083 if (complain
& tf_error
)
2084 error ("invalid value-initialization of reference type");
2085 return error_mark_node
;
2088 t
= build_min (CAST_EXPR
, type
, parms
);
2089 /* We don't know if it will or will not have side effects. */
2090 TREE_SIDE_EFFECTS (t
) = 1;
2094 if (! MAYBE_CLASS_TYPE_P (type
))
2096 if (parms
== NULL_TREE
)
2098 if (VOID_TYPE_P (type
))
2100 return build_value_init (cv_unqualified (type
), complain
);
2103 /* This must build a C cast. */
2104 parms
= build_x_compound_expr_from_list (parms
, ELK_FUNC_CAST
, complain
);
2105 return cp_build_c_cast (type
, parms
, complain
);
2108 /* Prepare to evaluate as a call to a constructor. If this expression
2109 is actually used, for example,
2111 return X (arg1, arg2, ...);
2113 then the slot being initialized will be filled in. */
2115 if (!complete_type_or_maybe_complain (type
, NULL_TREE
, complain
))
2116 return error_mark_node
;
2117 if (abstract_virtuals_error_sfinae (ACU_CAST
, type
, complain
))
2118 return error_mark_node
;
2122 If the expression list is a single-expression, the type
2123 conversion is equivalent (in definedness, and if defined in
2124 meaning) to the corresponding cast expression. */
2125 if (parms
&& TREE_CHAIN (parms
) == NULL_TREE
)
2126 return cp_build_c_cast (type
, TREE_VALUE (parms
), complain
);
2130 The expression T(), where T is a simple-type-specifier for a
2131 non-array complete object type or the (possibly cv-qualified)
2132 void type, creates an rvalue of the specified type, which is
2133 value-initialized. */
2135 if (parms
== NULL_TREE
)
2137 exp
= build_value_init (type
, complain
);
2138 exp
= get_target_expr_sfinae (exp
, complain
);
2142 /* Call the constructor. */
2143 parmvec
= make_tree_vector ();
2144 for (; parms
!= NULL_TREE
; parms
= TREE_CHAIN (parms
))
2145 vec_safe_push (parmvec
, TREE_VALUE (parms
));
2146 exp
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
2147 &parmvec
, type
, LOOKUP_NORMAL
, complain
);
2148 release_tree_vector (parmvec
);
2150 if (exp
== error_mark_node
)
2151 return error_mark_node
;
2153 return build_cplus_new (type
, exp
, complain
);
2157 /* Add new exception specifier SPEC, to the LIST we currently have.
2158 If it's already in LIST then do nothing.
2159 Moan if it's bad and we're allowed to. COMPLAIN < 0 means we
2160 know what we're doing. */
2163 add_exception_specifier (tree list
, tree spec
, int complain
)
2168 diagnostic_t diag_type
= DK_UNSPECIFIED
; /* none */
2170 if (spec
== error_mark_node
)
2173 gcc_assert (spec
&& (!list
|| TREE_VALUE (list
)));
2175 /* [except.spec] 1, type in an exception specifier shall not be
2176 incomplete, or pointer or ref to incomplete other than pointer
2178 is_ptr
= TYPE_PTR_P (core
);
2179 if (is_ptr
|| TREE_CODE (core
) == REFERENCE_TYPE
)
2180 core
= TREE_TYPE (core
);
2183 else if (VOID_TYPE_P (core
))
2185 else if (TREE_CODE (core
) == TEMPLATE_TYPE_PARM
)
2187 else if (processing_template_decl
)
2192 /* 15.4/1 says that types in an exception specifier must be complete,
2193 but it seems more reasonable to only require this on definitions
2194 and calls. So just give a pedwarn at this point; we will give an
2195 error later if we hit one of those two cases. */
2196 if (!COMPLETE_TYPE_P (complete_type (core
)))
2197 diag_type
= DK_PEDWARN
; /* pedwarn */
2204 for (probe
= list
; probe
; probe
= TREE_CHAIN (probe
))
2205 if (same_type_p (TREE_VALUE (probe
), spec
))
2208 list
= tree_cons (NULL_TREE
, spec
, list
);
2211 diag_type
= DK_ERROR
; /* error */
2213 if (diag_type
!= DK_UNSPECIFIED
2214 && (complain
& tf_warning_or_error
))
2215 cxx_incomplete_type_diagnostic (NULL_TREE
, core
, diag_type
);
2220 /* Like nothrow_spec_p, but don't abort on deferred noexcept. */
2223 nothrow_spec_p_uninst (const_tree spec
)
2225 if (DEFERRED_NOEXCEPT_SPEC_P (spec
))
2227 return nothrow_spec_p (spec
);
2230 /* Combine the two exceptions specifier lists LIST and ADD, and return
2234 merge_exception_specifiers (tree list
, tree add
)
2236 tree noex
, orig_list
;
2238 /* No exception-specifier or noexcept(false) are less strict than
2239 anything else. Prefer the newer variant (LIST). */
2240 if (!list
|| list
== noexcept_false_spec
)
2242 else if (!add
|| add
== noexcept_false_spec
)
2245 /* noexcept(true) and throw() are stricter than anything else.
2246 As above, prefer the more recent one (LIST). */
2247 if (nothrow_spec_p_uninst (add
))
2250 /* Two implicit noexcept specs (e.g. on a destructor) are equivalent. */
2251 if (UNEVALUATED_NOEXCEPT_SPEC_P (add
)
2252 && UNEVALUATED_NOEXCEPT_SPEC_P (list
))
2254 /* We should have instantiated other deferred noexcept specs by now. */
2255 gcc_assert (!DEFERRED_NOEXCEPT_SPEC_P (add
));
2257 if (nothrow_spec_p_uninst (list
))
2259 noex
= TREE_PURPOSE (list
);
2260 gcc_checking_assert (!TREE_PURPOSE (add
)
2261 || errorcount
|| !flag_exceptions
2262 || cp_tree_equal (noex
, TREE_PURPOSE (add
)));
2264 /* Combine the dynamic-exception-specifiers, if any. */
2266 for (; add
&& TREE_VALUE (add
); add
= TREE_CHAIN (add
))
2268 tree spec
= TREE_VALUE (add
);
2271 for (probe
= orig_list
; probe
&& TREE_VALUE (probe
);
2272 probe
= TREE_CHAIN (probe
))
2273 if (same_type_p (TREE_VALUE (probe
), spec
))
2277 spec
= build_tree_list (NULL_TREE
, spec
);
2278 TREE_CHAIN (spec
) = list
;
2283 /* Keep the noexcept-specifier at the beginning of the list. */
2284 if (noex
!= TREE_PURPOSE (list
))
2285 list
= tree_cons (noex
, TREE_VALUE (list
), TREE_CHAIN (list
));
2290 /* Subroutine of build_call. Ensure that each of the types in the
2291 exception specification is complete. Technically, 15.4/1 says that
2292 they need to be complete when we see a declaration of the function,
2293 but we should be able to get away with only requiring this when the
2294 function is defined or called. See also add_exception_specifier. */
2297 require_complete_eh_spec_types (tree fntype
, tree decl
)
2300 /* Don't complain about calls to op new. */
2301 if (decl
&& DECL_ARTIFICIAL (decl
))
2303 for (raises
= TYPE_RAISES_EXCEPTIONS (fntype
); raises
;
2304 raises
= TREE_CHAIN (raises
))
2306 tree type
= TREE_VALUE (raises
);
2307 if (type
&& !COMPLETE_TYPE_P (type
))
2311 ("call to function %qD which throws incomplete type %q#T",
2314 error ("call to function which throws incomplete type %q#T",
2321 #include "gt-cp-typeck2.h"