1 /* Report error messages, build initializers, and perform
2 some front-end optimizations for C++ compiler.
3 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
4 1999, 2000, 2001, 2002, 2004, 2005, 2006
5 Free Software Foundation, Inc.
6 Hacked by Michael Tiemann (tiemann@cygnus.com)
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING. If not, write to
22 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
23 Boston, MA 02110-1301, USA. */
26 /* This file is part of the C++ front end.
27 It contains routines to build C++ expressions given their operands,
28 including computing the types of the result, C and C++ specific error
29 checks, and some optimization. */
33 #include "coretypes.h"
40 #include "diagnostic.h"
43 process_init_constructor (tree type, tree init);
46 /* Print an error message stemming from an attempt to use
47 BASETYPE as a base class for TYPE. */
50 error_not_base_type (tree basetype, tree type)
52 if (TREE_CODE (basetype) == FUNCTION_DECL)
53 basetype = DECL_CONTEXT (basetype);
54 error ("type %qT is not a base type for type %qT", basetype, type);
55 return error_mark_node;
59 binfo_or_else (tree base, tree type)
61 tree binfo = lookup_base (type, base, ba_unique, NULL);
63 if (binfo == error_mark_node)
66 error_not_base_type (base, type);
70 /* According to ARM $7.1.6, "A `const' object may be initialized, but its
71 value may not be changed thereafter. */
74 readonly_error (tree arg, const char* string)
78 if (TREE_CODE (arg) == COMPONENT_REF)
80 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
81 fmt = "%s of data-member %qD in read-only structure";
83 fmt = "%s of read-only data-member %qD";
84 error (fmt, string, TREE_OPERAND (arg, 1));
86 else if (TREE_CODE (arg) == VAR_DECL)
88 if (DECL_LANG_SPECIFIC (arg)
89 && DECL_IN_AGGR_P (arg)
90 && !TREE_STATIC (arg))
91 fmt = "%s of constant field %qD";
93 fmt = "%s of read-only variable %qD";
94 error (fmt, string, arg);
96 else if (TREE_CODE (arg) == PARM_DECL)
97 error ("%s of read-only parameter %qD", string, arg);
98 else if (TREE_CODE (arg) == INDIRECT_REF
99 && TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0))) == REFERENCE_TYPE
100 && (TREE_CODE (TREE_OPERAND (arg, 0)) == VAR_DECL
101 || TREE_CODE (TREE_OPERAND (arg, 0)) == PARM_DECL))
102 error ("%s of read-only reference %qD", string, TREE_OPERAND (arg, 0));
103 else if (TREE_CODE (arg) == RESULT_DECL)
104 error ("%s of read-only named return value %qD", string, arg);
105 else if (TREE_CODE (arg) == FUNCTION_DECL)
106 error ("%s of function %qD", string, arg);
108 error ("%s of read-only location", string);
112 /* Structure that holds information about declarations whose type was
113 incomplete and we could not check whether it was abstract or not. */
115 struct pending_abstract_type GTY((chain_next ("%h.next")))
117 /* Declaration which we are checking for abstractness. It is either
118 a DECL node, or an IDENTIFIER_NODE if we do not have a full
119 declaration available. */
122 /* Type which will be checked for abstractness. */
125 /* Position of the declaration. This is only needed for IDENTIFIER_NODEs,
126 because DECLs already carry locus information. */
129 /* Link to the next element in list. */
130 struct pending_abstract_type* next;
134 /* Compute the hash value of the node VAL. This function is used by the
135 hash table abstract_pending_vars. */
138 pat_calc_hash (const void* val)
140 const struct pending_abstract_type *pat =
141 (const struct pending_abstract_type *) val;
142 return (hashval_t) TYPE_UID (pat->type);
146 /* Compare node VAL1 with the type VAL2. This function is used by the
147 hash table abstract_pending_vars. */
150 pat_compare (const void* val1, const void* val2)
152 const struct pending_abstract_type *pat1 =
153 (const struct pending_abstract_type *) val1;
154 tree type2 = (tree)val2;
156 return (pat1->type == type2);
159 /* Hash table that maintains pending_abstract_type nodes, for which we still
160 need to check for type abstractness. The key of the table is the type
161 of the declaration. */
162 static GTY ((param_is (struct pending_abstract_type)))
163 htab_t abstract_pending_vars = NULL;
166 /* This function is called after TYPE is completed, and will check if there
167 are pending declarations for which we still need to verify the abstractness
168 of TYPE, and emit a diagnostic (through abstract_virtuals_error) if TYPE
169 turned out to be incomplete. */
172 complete_type_check_abstract (tree type)
175 struct pending_abstract_type *pat;
176 location_t cur_loc = input_location;
178 gcc_assert (COMPLETE_TYPE_P (type));
180 if (!abstract_pending_vars)
183 /* Retrieve the list of pending declarations for this type. */
184 slot = htab_find_slot_with_hash (abstract_pending_vars, type,
185 (hashval_t)TYPE_UID (type), NO_INSERT);
188 pat = (struct pending_abstract_type*)*slot;
191 /* If the type is not abstract, do not do anything. */
192 if (CLASSTYPE_PURE_VIRTUALS (type))
194 struct pending_abstract_type *prev = 0, *next;
196 /* Reverse the list to emit the errors in top-down order. */
197 for (; pat; pat = next)
205 /* Go through the list, and call abstract_virtuals_error for each
206 element: it will issue a diagnostic if the type is abstract. */
209 gcc_assert (type == pat->type);
211 /* Tweak input_location so that the diagnostic appears at the correct
212 location. Notice that this is only needed if the decl is an
214 input_location = pat->locus;
215 abstract_virtuals_error (pat->decl, pat->type);
220 htab_clear_slot (abstract_pending_vars, slot);
222 input_location = cur_loc;
226 /* If TYPE has abstract virtual functions, issue an error about trying
227 to create an object of that type. DECL is the object declared, or
228 NULL_TREE if the declaration is unavailable. Returns 1 if an error
229 occurred; zero if all was well. */
232 abstract_virtuals_error (tree decl, tree type)
236 /* This function applies only to classes. Any other entity can never
238 if (!CLASS_TYPE_P (type))
241 /* If the type is incomplete, we register it within a hash table,
242 so that we can check again once it is completed. This makes sense
243 only for objects for which we have a declaration or at least a
245 if (!COMPLETE_TYPE_P (type))
248 struct pending_abstract_type *pat;
250 gcc_assert (!decl || DECL_P (decl)
251 || TREE_CODE (decl) == IDENTIFIER_NODE);
253 if (!abstract_pending_vars)
254 abstract_pending_vars = htab_create_ggc (31, &pat_calc_hash,
257 slot = htab_find_slot_with_hash (abstract_pending_vars, type,
258 (hashval_t)TYPE_UID (type), INSERT);
260 pat = GGC_NEW (struct pending_abstract_type);
263 pat->locus = ((decl && DECL_P (decl))
264 ? DECL_SOURCE_LOCATION (decl)
267 pat->next = (struct pending_abstract_type *) *slot;
273 if (!TYPE_SIZE (type))
274 /* TYPE is being defined, and during that time
275 CLASSTYPE_PURE_VIRTUALS holds the inline friends. */
278 pure = CLASSTYPE_PURE_VIRTUALS (type);
284 if (TREE_CODE (decl) == RESULT_DECL)
287 if (TREE_CODE (decl) == VAR_DECL)
288 error ("cannot declare variable %q+D to be of abstract "
289 "type %qT", decl, type);
290 else if (TREE_CODE (decl) == PARM_DECL)
291 error ("cannot declare parameter %q+D to be of abstract type %qT",
293 else if (TREE_CODE (decl) == FIELD_DECL)
294 error ("cannot declare field %q+D to be of abstract type %qT",
296 else if (TREE_CODE (decl) == FUNCTION_DECL
297 && TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE)
298 error ("invalid abstract return type for member function %q+#D", decl);
299 else if (TREE_CODE (decl) == FUNCTION_DECL)
300 error ("invalid abstract return type for function %q+#D", decl);
301 else if (TREE_CODE (decl) == IDENTIFIER_NODE)
302 /* Here we do not have location information. */
303 error ("invalid abstract type %qT for %qE", type, decl);
305 error ("invalid abstract type for %q+D", decl);
308 error ("cannot allocate an object of abstract type %qT", type);
310 /* Only go through this once. */
311 if (VEC_length (tree, pure))
316 inform ("%J because the following virtual functions are pure "
317 "within %qT:", TYPE_MAIN_DECL (type), type);
319 for (ix = 0; VEC_iterate (tree, pure, ix, fn); ix++)
320 inform ("\t%+#D", fn);
321 /* Now truncate the vector. This leaves it non-null, so we know
322 there are pure virtuals, but empty so we don't list them out
324 VEC_truncate (tree, pure, 0);
327 inform ("%J since type %qT has pure virtual functions",
328 TYPE_MAIN_DECL (type), type);
333 /* Print an error message for invalid use of an incomplete type.
334 VALUE is the expression that was used (or 0 if that isn't known)
335 and TYPE is the type that was invalid. DIAG_TYPE indicates the
336 type of diagnostic: 0 for an error, 1 for a warning, 2 for a
340 cxx_incomplete_type_diagnostic (tree value, tree type, int diag_type)
343 void (*p_msg) (const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
347 else if (diag_type == 2)
352 /* Avoid duplicate error message. */
353 if (TREE_CODE (type) == ERROR_MARK)
356 if (value != 0 && (TREE_CODE (value) == VAR_DECL
357 || TREE_CODE (value) == PARM_DECL
358 || TREE_CODE (value) == FIELD_DECL))
360 p_msg ("%q+D has incomplete type", value);
364 /* We must print an error message. Be clever about what it says. */
366 switch (TREE_CODE (type))
372 p_msg ("invalid use of incomplete type %q#T", type);
373 if (!TYPE_TEMPLATE_INFO (type))
374 p_msg ("forward declaration of %q+#T", type);
376 p_msg ("declaration of %q+#T", type);
380 p_msg ("invalid use of %qT", type);
384 if (TYPE_DOMAIN (type))
386 type = TREE_TYPE (type);
389 p_msg ("invalid use of array with unspecified bounds");
394 p_msg ("invalid use of member (did you forget the %<&%> ?)");
397 case TEMPLATE_TYPE_PARM:
398 p_msg ("invalid use of template type parameter %qT", type);
401 case BOUND_TEMPLATE_TEMPLATE_PARM:
402 p_msg ("invalid use of template template parameter %qT",
407 p_msg ("invalid use of dependent type %qT", type);
411 if (value && TREE_CODE (value) == COMPONENT_REF)
413 else if (value && TREE_CODE (value) == ADDR_EXPR)
414 p_msg ("address of overloaded function with no contextual "
416 else if (value && TREE_CODE (value) == OVERLOAD)
417 p_msg ("overloaded function with no contextual type information");
419 p_msg ("insufficient contextual information to determine type");
427 /* Backward-compatibility interface to incomplete_type_diagnostic;
428 required by ../tree.c. */
429 #undef cxx_incomplete_type_error
431 cxx_incomplete_type_error (tree value, tree type)
433 cxx_incomplete_type_diagnostic (value, type, 0);
437 /* The recursive part of split_nonconstant_init. DEST is an lvalue
438 expression to which INIT should be assigned. INIT is a CONSTRUCTOR. */
441 split_nonconstant_init_1 (tree dest, tree init)
443 unsigned HOST_WIDE_INT idx;
444 tree field_index, value;
445 tree type = TREE_TYPE (dest);
446 tree inner_type = NULL;
447 bool array_type_p = false;
449 switch (TREE_CODE (type))
452 inner_type = TREE_TYPE (type);
458 case QUAL_UNION_TYPE:
459 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx,
462 /* The current implementation of this algorithm assumes that
463 the field was set for all the elements. This is usually done
464 by process_init_constructor. */
465 gcc_assert (field_index);
468 inner_type = TREE_TYPE (field_index);
470 if (TREE_CODE (value) == CONSTRUCTOR)
475 sub = build4 (ARRAY_REF, inner_type, dest, field_index,
476 NULL_TREE, NULL_TREE);
478 sub = build3 (COMPONENT_REF, inner_type, dest, field_index,
481 split_nonconstant_init_1 (sub, value);
483 else if (!initializer_constant_valid_p (value, inner_type))
488 /* FIXME: Ordered removal is O(1) so the whole function is
489 worst-case quadratic. This could be fixed using an aside
490 bitmap to record which elements must be removed and remove
491 them all at the same time. Or by merging
492 split_non_constant_init into process_init_constructor_array,
493 that is separating constants from non-constants while building
495 VEC_ordered_remove (constructor_elt, CONSTRUCTOR_ELTS (init),
500 sub = build4 (ARRAY_REF, inner_type, dest, field_index,
501 NULL_TREE, NULL_TREE);
503 sub = build3 (COMPONENT_REF, inner_type, dest, field_index,
506 code = build2 (INIT_EXPR, inner_type, sub, value);
507 code = build_stmt (EXPR_STMT, code);
515 if (!initializer_constant_valid_p (init, type))
518 tree cons = copy_node (init);
519 CONSTRUCTOR_ELTS (init) = NULL;
520 code = build2 (MODIFY_EXPR, type, dest, cons);
521 code = build_stmt (EXPR_STMT, code);
530 /* The rest of the initializer is now a constant. */
531 TREE_CONSTANT (init) = 1;
534 /* A subroutine of store_init_value. Splits non-constant static
535 initializer INIT into a constant part and generates code to
536 perform the non-constant part of the initialization to DEST.
537 Returns the code for the runtime init. */
540 split_nonconstant_init (tree dest, tree init)
544 if (TREE_CODE (init) == CONSTRUCTOR)
546 code = push_stmt_list ();
547 split_nonconstant_init_1 (dest, init);
548 code = pop_stmt_list (code);
549 DECL_INITIAL (dest) = init;
550 TREE_READONLY (dest) = 0;
553 code = build2 (INIT_EXPR, TREE_TYPE (dest), dest, init);
558 /* Perform appropriate conversions on the initial value of a variable,
559 store it in the declaration DECL,
560 and print any error messages that are appropriate.
561 If the init is invalid, store an ERROR_MARK.
563 C++: Note that INIT might be a TREE_LIST, which would mean that it is
564 a base class initializer for some aggregate type, hopefully compatible
565 with DECL. If INIT is a single element, and DECL is an aggregate
566 type, we silently convert INIT into a TREE_LIST, allowing a constructor
569 If INIT is a TREE_LIST and there is no constructor, turn INIT
570 into a CONSTRUCTOR and use standard initialization techniques.
571 Perhaps a warning should be generated?
573 Returns code to be executed if initialization could not be performed
574 for static variable. In that case, caller must emit the code. */
577 store_init_value (tree decl, tree init)
581 /* If variable's type was invalidly declared, just ignore it. */
583 type = TREE_TYPE (decl);
584 if (TREE_CODE (type) == ERROR_MARK)
587 if (IS_AGGR_TYPE (type))
589 gcc_assert (TYPE_HAS_TRIVIAL_INIT_REF (type)
590 || TREE_CODE (init) == CONSTRUCTOR);
592 if (TREE_CODE (init) == TREE_LIST)
594 error ("constructor syntax used, but no constructor declared "
595 "for type %qT", type);
596 init = build_constructor_from_list (NULL_TREE, nreverse (init));
599 else if (TREE_CODE (init) == TREE_LIST
600 && TREE_TYPE (init) != unknown_type_node)
602 if (TREE_CODE (decl) == RESULT_DECL)
603 init = build_x_compound_expr_from_list (init,
604 "return value initializer");
605 else if (TREE_CODE (init) == TREE_LIST
606 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
608 error ("cannot initialize arrays using this syntax");
612 /* We get here with code like `int a (2);' */
613 init = build_x_compound_expr_from_list (init, "initializer");
616 /* End of special C++ code. */
618 /* Digest the specified initializer into an expression. */
619 value = digest_init (type, init);
620 /* If the initializer is not a constant, fill in DECL_INITIAL with
621 the bits that are constant, and then return an expression that
622 will perform the dynamic initialization. */
623 if (value != error_mark_node
624 && (TREE_SIDE_EFFECTS (value)
625 || ! initializer_constant_valid_p (value, TREE_TYPE (value))))
626 return split_nonconstant_init (decl, value);
627 /* If the value is a constant, just put it in DECL_INITIAL. If DECL
628 is an automatic variable, the middle end will turn this into a
629 dynamic initialization later. */
630 DECL_INITIAL (decl) = value;
635 /* Process the initializer INIT for a variable of type TYPE, emitting
636 diagnostics for invalid initializers and converting the initializer as
639 For aggregate types, it assumes that reshape_init has already run, thus the
640 initializer will have the right shape (brace elision has been undone). */
643 digest_init (tree type, tree init)
645 enum tree_code code = TREE_CODE (type);
647 if (init == error_mark_node)
648 return error_mark_node;
652 /* We must strip the outermost array type when completing the type,
653 because the its bounds might be incomplete at the moment. */
654 if (!complete_type_or_else (TREE_CODE (type) == ARRAY_TYPE
655 ? TREE_TYPE (type) : type, NULL_TREE))
656 return error_mark_node;
658 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue
659 (g++.old-deja/g++.law/casts2.C). */
660 if (TREE_CODE (init) == NON_LVALUE_EXPR)
661 init = TREE_OPERAND (init, 0);
663 /* Initialization of an array of chars from a string constant. The initializer
664 can be optionally enclosed in braces, but reshape_init has already removed
665 them if they were present. */
666 if (code == ARRAY_TYPE)
668 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
669 if (char_type_p (typ1)
671 && TREE_CODE (init) == STRING_CST)
673 tree char_type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (init)));
675 if (char_type != char_type_node
676 && TYPE_PRECISION (typ1) == BITS_PER_UNIT)
678 error ("char-array initialized from wide string");
679 return error_mark_node;
681 if (char_type == char_type_node
682 && TYPE_PRECISION (typ1) != BITS_PER_UNIT)
684 error ("int-array initialized from non-wide string");
685 return error_mark_node;
688 TREE_TYPE (init) = type;
689 if (TYPE_DOMAIN (type) != 0 && TREE_CONSTANT (TYPE_SIZE (type)))
691 int size = TREE_INT_CST_LOW (TYPE_SIZE (type));
692 size = (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
693 /* In C it is ok to subtract 1 from the length of the string
694 because it's ok to ignore the terminating null char that is
695 counted in the length of the constant, but in C++ this would
697 if (size < TREE_STRING_LENGTH (init))
698 pedwarn ("initializer-string for array of chars is too long");
704 /* Handle scalar types (including conversions) and references. */
705 if (SCALAR_TYPE_P (type) || code == REFERENCE_TYPE)
706 return convert_for_initialization (0, type, init, LOOKUP_NORMAL,
707 "initialization", NULL_TREE, 0);
709 /* Come here only for aggregates: records, arrays, unions, complex numbers
711 gcc_assert (TREE_CODE (type) == ARRAY_TYPE
712 || TREE_CODE (type) == VECTOR_TYPE
713 || TREE_CODE (type) == RECORD_TYPE
714 || TREE_CODE (type) == UNION_TYPE
715 || TREE_CODE (type) == COMPLEX_TYPE);
717 if (BRACE_ENCLOSED_INITIALIZER_P (init))
718 return process_init_constructor (type, init);
721 if (COMPOUND_LITERAL_P (init) && TREE_CODE (type) == ARRAY_TYPE)
723 error ("cannot initialize aggregate of type %qT with "
724 "a compound literal", type);
726 return error_mark_node;
729 if (TREE_CODE (type) == ARRAY_TYPE
730 && TREE_CODE (init) != CONSTRUCTOR)
732 error ("array must be initialized with a brace-enclosed"
734 return error_mark_node;
737 return convert_for_initialization (NULL_TREE, type, init,
738 LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING,
739 "initialization", NULL_TREE, 0);
744 /* Set of flags used within process_init_constructor to describe the
746 #define PICFLAG_ERRONEOUS 1
747 #define PICFLAG_NOT_ALL_CONSTANT 2
748 #define PICFLAG_NOT_ALL_SIMPLE 4
750 /* Given an initializer INIT, return the flag (PICFLAG_*) which better
754 picflag_from_initializer (tree init)
756 if (init == error_mark_node)
757 return PICFLAG_ERRONEOUS;
758 else if (!TREE_CONSTANT (init))
759 return PICFLAG_NOT_ALL_CONSTANT;
760 else if (!initializer_constant_valid_p (init, TREE_TYPE (init)))
761 return PICFLAG_NOT_ALL_SIMPLE;
765 /* Subroutine of process_init_constructor, which will process an initializer
766 INIT for a array or vector of type TYPE. Returns the flags (PICFLAG_*) which
767 describe the initializers. */
770 process_init_constructor_array (tree type, tree init)
772 unsigned HOST_WIDE_INT i, len = 0;
774 bool unbounded = false;
776 VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (init);
778 gcc_assert (TREE_CODE (type) == ARRAY_TYPE
779 || TREE_CODE (type) == VECTOR_TYPE);
781 if (TREE_CODE (type) == ARRAY_TYPE)
783 tree domain = TYPE_DOMAIN (type);
785 len = (TREE_INT_CST_LOW (TYPE_MAX_VALUE (domain))
786 - TREE_INT_CST_LOW (TYPE_MIN_VALUE (domain))
789 unbounded = true; /* Take as many as there are. */
792 /* Vectors are like simple fixed-size arrays. */
793 len = TYPE_VECTOR_SUBPARTS (type);
795 /* There cannot be more initializers than needed as otherwise
796 reshape_init would have already rejected the initializer. */
798 gcc_assert (VEC_length (constructor_elt, v) <= len);
800 for (i = 0; VEC_iterate (constructor_elt, v, i, ce); ++i)
804 gcc_assert (TREE_CODE (ce->index) == INTEGER_CST);
805 if (compare_tree_int (ce->index, i) != 0)
807 ce->value = error_mark_node;
808 sorry ("non-trivial designated initializers not supported");
812 ce->index = size_int (i);
813 gcc_assert (ce->value);
814 ce->value = digest_init (TREE_TYPE (type), ce->value);
816 if (ce->value != error_mark_node)
817 gcc_assert (same_type_ignoring_top_level_qualifiers_p
818 (TREE_TYPE (type), TREE_TYPE (ce->value)));
820 flags |= picflag_from_initializer (ce->value);
823 /* No more initializers. If the array is unbounded, we are done. Otherwise,
824 we must add initializers ourselves. */
830 if (TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (type)))
832 /* If this type needs constructors run for default-initialization,
833 we can't rely on the back end to do it for us, so build up
834 TARGET_EXPRs. If the type in question is a class, just build
835 one up; if it's an array, recurse. */
836 if (IS_AGGR_TYPE (TREE_TYPE (type)))
837 next = build_functional_cast (TREE_TYPE (type), NULL_TREE);
839 next = build_constructor (NULL_TREE, NULL);
840 next = digest_init (TREE_TYPE (type), next);
842 else if (!zero_init_p (TREE_TYPE (type)))
843 next = build_zero_init (TREE_TYPE (type),
845 /*static_storage_p=*/false);
847 /* The default zero-initialization is fine for us; don't
848 add anything to the CONSTRUCTOR. */
851 flags |= picflag_from_initializer (next);
852 CONSTRUCTOR_APPEND_ELT (v, size_int (i), next);
855 CONSTRUCTOR_ELTS (init) = v;
859 /* Subroutine of process_init_constructor, which will process an initializer
860 INIT for a class of type TYPE. Returns the flags (PICFLAG_*) which describe
864 process_init_constructor_record (tree type, tree init)
866 VEC(constructor_elt,gc) *v = NULL;
869 unsigned HOST_WIDE_INT idx = 0;
871 gcc_assert (TREE_CODE (type) == RECORD_TYPE);
872 gcc_assert (!CLASSTYPE_VBASECLASSES (type));
873 gcc_assert (!TYPE_BINFO (type)
874 || !BINFO_N_BASE_BINFOS (TYPE_BINFO (type)));
875 gcc_assert (!TYPE_POLYMORPHIC_P (type));
877 /* Generally, we will always have an index for each initializer (which is
878 a FIELD_DECL, put by reshape_init), but compound literals don't go trough
879 reshape_init. So we need to handle both cases. */
880 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
884 if (!DECL_NAME (field) && DECL_C_BIT_FIELD (field))
886 flags |= picflag_from_initializer (integer_zero_node);
887 CONSTRUCTOR_APPEND_ELT (v, field, integer_zero_node);
891 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
894 if (idx < VEC_length (constructor_elt, CONSTRUCTOR_ELTS (init)))
896 constructor_elt *ce = VEC_index (constructor_elt,
897 CONSTRUCTOR_ELTS (init), idx);
900 /* We can have either a FIELD_DECL or an IDENTIFIER_NODE. The
901 latter case can happen in templates where lookup has to be
903 gcc_assert (TREE_CODE (ce->index) == FIELD_DECL
904 || TREE_CODE (ce->index) == IDENTIFIER_NODE);
905 if (ce->index != field
906 && ce->index != DECL_NAME (field))
908 ce->value = error_mark_node;
909 sorry ("non-trivial designated initializers not supported");
913 gcc_assert (ce->value);
914 next = digest_init (TREE_TYPE (field), ce->value);
917 else if (TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (field)))
919 /* If this type needs constructors run for
920 default-initialization, we can't rely on the back end to do it
921 for us, so build up TARGET_EXPRs. If the type in question is
922 a class, just build one up; if it's an array, recurse. */
923 if (IS_AGGR_TYPE (TREE_TYPE (field)))
924 next = build_functional_cast (TREE_TYPE (field), NULL_TREE);
926 next = build_constructor (NULL_TREE, NULL);
928 next = digest_init (TREE_TYPE (field), next);
930 /* Warn when some struct elements are implicitly initialized. */
931 warning (OPT_Wmissing_field_initializers,
932 "missing initializer for member %qD", field);
936 if (TREE_READONLY (field))
937 error ("uninitialized const member %qD", field);
938 else if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (TREE_TYPE (field)))
939 error ("member %qD with uninitialized const fields", field);
940 else if (TREE_CODE (TREE_TYPE (field)) == REFERENCE_TYPE)
941 error ("member %qD is uninitialized reference", field);
943 /* Warn when some struct elements are implicitly initialized
945 warning (OPT_Wmissing_field_initializers,
946 "missing initializer for member %qD", field);
948 if (!zero_init_p (TREE_TYPE (field)))
949 next = build_zero_init (TREE_TYPE (field), /*nelts=*/NULL_TREE,
950 /*static_storage_p=*/false);
952 /* The default zero-initialization is fine for us; don't
953 add anything to the CONSTRUCTOR. */
957 flags |= picflag_from_initializer (next);
958 CONSTRUCTOR_APPEND_ELT (v, field, next);
961 CONSTRUCTOR_ELTS (init) = v;
965 /* Subroutine of process_init_constructor, which will process a single
966 initializer INIT for a union of type TYPE. Returns the flags (PICFLAG_*)
967 which describe the initializer. */
970 process_init_constructor_union (tree type, tree init)
974 /* If the initializer was empty, use default zero initialization. */
975 if (VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (init)))
978 gcc_assert (VEC_length (constructor_elt, CONSTRUCTOR_ELTS (init)) == 1);
979 ce = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (init), 0);
981 /* If this element specifies a field, initialize via that field. */
984 if (TREE_CODE (ce->index) == FIELD_DECL)
986 else if (TREE_CODE (ce->index) == IDENTIFIER_NODE)
988 /* This can happen within a cast, see g++.dg/opt/cse2.C. */
989 tree name = ce->index;
991 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
992 if (DECL_NAME (field) == name)
996 error ("no field %qD found in union being initialized", field);
997 ce->value = error_mark_node;
1003 gcc_assert (TREE_CODE (ce->index) == INTEGER_CST
1004 || TREE_CODE (ce->index) == RANGE_EXPR);
1005 error ("index value instead of field name in union initializer");
1006 ce->value = error_mark_node;
1011 /* Find the first named field. ANSI decided in September 1990
1012 that only named fields count here. */
1013 tree field = TYPE_FIELDS (type);
1014 while (field && (!DECL_NAME (field) || TREE_CODE (field) != FIELD_DECL))
1015 field = TREE_CHAIN (field);
1020 if (ce->value && ce->value != error_mark_node)
1021 ce->value = digest_init (TREE_TYPE (ce->index), ce->value);
1023 return picflag_from_initializer (ce->value);
1026 /* Process INIT, a constructor for a variable of aggregate type TYPE. The
1027 constructor is a brace-enclosed initializer, and will be modified in-place.
1029 Each element is converted to the right type through digest_init, and
1030 missing initializers are added following the language rules (zero-padding,
1033 After the execution, the initializer will have TREE_CONSTANT if all elts are
1034 constant, and TREE_STATIC set if, in addition, all elts are simple enough
1035 constants that the assembler and linker can compute them.
1037 The function returns the initializer itself, or error_mark_node in case
1041 process_init_constructor (tree type, tree init)
1045 gcc_assert (BRACE_ENCLOSED_INITIALIZER_P (init));
1047 if (TREE_CODE (type) == ARRAY_TYPE || TREE_CODE (type) == VECTOR_TYPE)
1048 flags = process_init_constructor_array (type, init);
1049 else if (TREE_CODE (type) == RECORD_TYPE)
1050 flags = process_init_constructor_record (type, init);
1051 else if (TREE_CODE (type) == UNION_TYPE)
1052 flags = process_init_constructor_union (type, init);
1056 if (flags & PICFLAG_ERRONEOUS)
1057 return error_mark_node;
1059 TREE_TYPE (init) = type;
1060 if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type) == NULL_TREE)
1061 cp_complete_array_type (&TREE_TYPE (init), init, /*do_default=*/0);
1062 if (!(flags & PICFLAG_NOT_ALL_CONSTANT))
1064 TREE_CONSTANT (init) = 1;
1065 TREE_INVARIANT (init) = 1;
1066 if (!(flags & PICFLAG_NOT_ALL_SIMPLE))
1067 TREE_STATIC (init) = 1;
1072 /* Given a structure or union value DATUM, construct and return
1073 the structure or union component which results from narrowing
1074 that value to the base specified in BASETYPE. For example, given the
1077 class L { int ii; };
1078 class A : L { ... };
1079 class B : L { ... };
1080 class C : A, B { ... };
1088 x.A::ii refers to the ii member of the L part of
1089 the A part of the C object named by X. In this case,
1090 DATUM would be x, and BASETYPE would be A.
1092 I used to think that this was nonconformant, that the standard specified
1093 that first we look up ii in A, then convert x to an L& and pull out the
1094 ii part. But in fact, it does say that we convert x to an A&; A here
1095 is known as the "naming class". (jason 2000-12-19)
1097 BINFO_P points to a variable initialized either to NULL_TREE or to the
1098 binfo for the specific base subobject we want to convert to. */
1101 build_scoped_ref (tree datum, tree basetype, tree* binfo_p)
1105 if (datum == error_mark_node)
1106 return error_mark_node;
1110 binfo = lookup_base (TREE_TYPE (datum), basetype, ba_check, NULL);
1112 if (!binfo || binfo == error_mark_node)
1114 *binfo_p = NULL_TREE;
1116 error_not_base_type (basetype, TREE_TYPE (datum));
1117 return error_mark_node;
1121 return build_base_path (PLUS_EXPR, datum, binfo, 1);
1124 /* Build a reference to an object specified by the C++ `->' operator.
1125 Usually this just involves dereferencing the object, but if the
1126 `->' operator is overloaded, then such overloads must be
1127 performed until an object which does not have the `->' operator
1128 overloaded is found. An error is reported when circular pointer
1129 delegation is detected. */
1132 build_x_arrow (tree expr)
1134 tree orig_expr = expr;
1135 tree types_memoized = NULL_TREE;
1136 tree type = TREE_TYPE (expr);
1137 tree last_rval = NULL_TREE;
1139 if (type == error_mark_node)
1140 return error_mark_node;
1142 if (processing_template_decl)
1144 if (type_dependent_expression_p (expr))
1145 return build_min_nt (ARROW_EXPR, expr);
1146 expr = build_non_dependent_expr (expr);
1149 if (IS_AGGR_TYPE (type))
1151 while ((expr = build_new_op (COMPONENT_REF, LOOKUP_NORMAL, expr,
1152 NULL_TREE, NULL_TREE,
1153 /*overloaded_p=*/NULL)))
1155 if (expr == error_mark_node)
1156 return error_mark_node;
1158 if (value_member (TREE_TYPE (expr), types_memoized))
1160 error ("circular pointer delegation detected");
1161 return error_mark_node;
1165 types_memoized = tree_cons (NULL_TREE, TREE_TYPE (expr),
1171 if (last_rval == NULL_TREE)
1173 error ("base operand of %<->%> has non-pointer type %qT", type);
1174 return error_mark_node;
1177 if (TREE_CODE (TREE_TYPE (last_rval)) == REFERENCE_TYPE)
1178 last_rval = convert_from_reference (last_rval);
1181 last_rval = decay_conversion (expr);
1183 if (TREE_CODE (TREE_TYPE (last_rval)) == POINTER_TYPE)
1185 if (processing_template_decl)
1187 expr = build_min_non_dep (ARROW_EXPR, last_rval, orig_expr);
1188 /* It will be dereferenced. */
1189 TREE_TYPE (expr) = TREE_TYPE (TREE_TYPE (last_rval));
1193 return build_indirect_ref (last_rval, NULL);
1197 error ("result of %<operator->()%> yields non-pointer result");
1199 error ("base operand of %<->%> is not a pointer");
1200 return error_mark_node;
1203 /* Return an expression for "DATUM .* COMPONENT". DATUM has not
1204 already been checked out to be of aggregate type. */
1207 build_m_component_ref (tree datum, tree component)
1215 if (error_operand_p (datum) || error_operand_p (component))
1216 return error_mark_node;
1218 ptrmem_type = TREE_TYPE (component);
1219 if (!TYPE_PTR_TO_MEMBER_P (ptrmem_type))
1221 error ("%qE cannot be used as a member pointer, since it is of "
1223 component, ptrmem_type);
1224 return error_mark_node;
1227 objtype = TYPE_MAIN_VARIANT (TREE_TYPE (datum));
1228 if (! IS_AGGR_TYPE (objtype))
1230 error ("cannot apply member pointer %qE to %qE, which is of "
1231 "non-class type %qT",
1232 component, datum, objtype);
1233 return error_mark_node;
1236 type = TYPE_PTRMEM_POINTED_TO_TYPE (ptrmem_type);
1237 ctype = complete_type (TYPE_PTRMEM_CLASS_TYPE (ptrmem_type));
1239 if (!COMPLETE_TYPE_P (ctype))
1241 if (!same_type_p (ctype, objtype))
1247 binfo = lookup_base (objtype, ctype, ba_check, NULL);
1252 error ("pointer to member type %qT incompatible with object "
1255 return error_mark_node;
1257 else if (binfo == error_mark_node)
1258 return error_mark_node;
1261 if (TYPE_PTRMEM_P (ptrmem_type))
1263 /* Compute the type of the field, as described in [expr.ref].
1264 There's no such thing as a mutable pointer-to-member, so
1265 things are not as complex as they are for references to
1266 non-static data members. */
1267 type = cp_build_qualified_type (type,
1268 (cp_type_quals (type)
1269 | cp_type_quals (TREE_TYPE (datum))));
1271 datum = build_address (datum);
1273 /* Convert object to the correct base. */
1275 datum = build_base_path (PLUS_EXPR, datum, binfo, 1);
1277 /* Build an expression for "object + offset" where offset is the
1278 value stored in the pointer-to-data-member. */
1279 datum = build2 (PLUS_EXPR, build_pointer_type (type),
1280 datum, build_nop (ptrdiff_type_node, component));
1281 return build_indirect_ref (datum, 0);
1284 return build2 (OFFSET_REF, type, datum, component);
1287 /* Return a tree node for the expression TYPENAME '(' PARMS ')'. */
1290 build_functional_cast (tree exp, tree parms)
1292 /* This is either a call to a constructor,
1293 or a C cast in C++'s `functional' notation. */
1296 if (exp == error_mark_node || parms == error_mark_node)
1297 return error_mark_node;
1299 if (TREE_CODE (exp) == TYPE_DECL)
1300 type = TREE_TYPE (exp);
1304 if (processing_template_decl)
1306 tree t = build_min (CAST_EXPR, type, parms);
1307 /* We don't know if it will or will not have side effects. */
1308 TREE_SIDE_EFFECTS (t) = 1;
1312 if (! IS_AGGR_TYPE (type))
1314 if (parms == NULL_TREE)
1315 return cp_convert (type, integer_zero_node);
1317 /* This must build a C cast. */
1318 parms = build_x_compound_expr_from_list (parms, "functional cast");
1319 return build_c_cast (type, parms);
1322 /* Prepare to evaluate as a call to a constructor. If this expression
1323 is actually used, for example,
1325 return X (arg1, arg2, ...);
1327 then the slot being initialized will be filled in. */
1329 if (!complete_type_or_else (type, NULL_TREE))
1330 return error_mark_node;
1331 if (abstract_virtuals_error (NULL_TREE, type))
1332 return error_mark_node;
1334 if (parms && TREE_CHAIN (parms) == NULL_TREE)
1335 return build_c_cast (type, TREE_VALUE (parms));
1337 /* We need to zero-initialize POD types. */
1338 if (parms == NULL_TREE
1339 && !CLASSTYPE_NON_POD_P (type)
1340 && TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
1342 exp = build_constructor (type, NULL);
1343 return get_target_expr (exp);
1346 exp = build_special_member_call (NULL_TREE, complete_ctor_identifier, parms,
1347 type, LOOKUP_NORMAL);
1349 if (exp == error_mark_node)
1350 return error_mark_node;
1352 return build_cplus_new (type, exp);
1356 /* Add new exception specifier SPEC, to the LIST we currently have.
1357 If it's already in LIST then do nothing.
1358 Moan if it's bad and we're allowed to. COMPLAIN < 0 means we
1359 know what we're doing. */
1362 add_exception_specifier (tree list, tree spec, int complain)
1367 int diag_type = -1; /* none */
1369 if (spec == error_mark_node)
1372 gcc_assert (spec && (!list || TREE_VALUE (list)));
1374 /* [except.spec] 1, type in an exception specifier shall not be
1375 incomplete, or pointer or ref to incomplete other than pointer
1377 is_ptr = TREE_CODE (core) == POINTER_TYPE;
1378 if (is_ptr || TREE_CODE (core) == REFERENCE_TYPE)
1379 core = TREE_TYPE (core);
1382 else if (VOID_TYPE_P (core))
1384 else if (TREE_CODE (core) == TEMPLATE_TYPE_PARM)
1386 else if (processing_template_decl)
1391 /* 15.4/1 says that types in an exception specifier must be complete,
1392 but it seems more reasonable to only require this on definitions
1393 and calls. So just give a pedwarn at this point; we will give an
1394 error later if we hit one of those two cases. */
1395 if (!COMPLETE_TYPE_P (complete_type (core)))
1396 diag_type = 2; /* pedwarn */
1403 for (probe = list; probe; probe = TREE_CHAIN (probe))
1404 if (same_type_p (TREE_VALUE (probe), spec))
1407 list = tree_cons (NULL_TREE, spec, list);
1410 diag_type = 0; /* error */
1412 if (diag_type >= 0 && complain)
1413 cxx_incomplete_type_diagnostic (NULL_TREE, core, diag_type);
1418 /* Combine the two exceptions specifier lists LIST and ADD, and return
1422 merge_exception_specifiers (tree list, tree add)
1426 else if (!TREE_VALUE (list))
1428 else if (!TREE_VALUE (add))
1432 tree orig_list = list;
1434 for (; add; add = TREE_CHAIN (add))
1436 tree spec = TREE_VALUE (add);
1439 for (probe = orig_list; probe; probe = TREE_CHAIN (probe))
1440 if (same_type_p (TREE_VALUE (probe), spec))
1444 spec = build_tree_list (NULL_TREE, spec);
1445 TREE_CHAIN (spec) = list;
1453 /* Subroutine of build_call. Ensure that each of the types in the
1454 exception specification is complete. Technically, 15.4/1 says that
1455 they need to be complete when we see a declaration of the function,
1456 but we should be able to get away with only requiring this when the
1457 function is defined or called. See also add_exception_specifier. */
1460 require_complete_eh_spec_types (tree fntype, tree decl)
1463 /* Don't complain about calls to op new. */
1464 if (decl && DECL_ARTIFICIAL (decl))
1466 for (raises = TYPE_RAISES_EXCEPTIONS (fntype); raises;
1467 raises = TREE_CHAIN (raises))
1469 tree type = TREE_VALUE (raises);
1470 if (type && !COMPLETE_TYPE_P (type))
1474 ("call to function %qD which throws incomplete type %q#T",
1477 error ("call to function which throws incomplete type %q#T",
1484 #include "gt-cp-typeck2.h"