1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987-2015 Free Software Foundation, Inc.
3 Contributed by Michael Tiemann (tiemann@cygnus.com)
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
22 /* High-level class interface. */
26 #include "coretypes.h"
30 #include "double-int.h"
39 #include "stringpool.h"
40 #include "stor-layout.h"
42 #include "hash-table.h"
50 #include "plugin-api.h"
51 #include "hard-reg-set.h"
57 #include "splay-tree.h"
61 /* The number of nested classes being processed. If we are not in the
62 scope of any class, this is zero. */
64 int current_class_depth;
66 /* In order to deal with nested classes, we keep a stack of classes.
67 The topmost entry is the innermost class, and is the entry at index
68 CURRENT_CLASS_DEPTH */
70 typedef struct class_stack_node {
71 /* The name of the class. */
74 /* The _TYPE node for the class. */
77 /* The access specifier pending for new declarations in the scope of
81 /* If were defining TYPE, the names used in this class. */
82 splay_tree names_used;
84 /* Nonzero if this class is no longer open, because of a call to
87 }* class_stack_node_t;
89 typedef struct vtbl_init_data_s
91 /* The base for which we're building initializers. */
93 /* The type of the most-derived type. */
95 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
96 unless ctor_vtbl_p is true. */
98 /* The negative-index vtable initializers built up so far. These
99 are in order from least negative index to most negative index. */
100 vec<constructor_elt, va_gc> *inits;
101 /* The binfo for the virtual base for which we're building
102 vcall offset initializers. */
104 /* The functions in vbase for which we have already provided vcall
106 vec<tree, va_gc> *fns;
107 /* The vtable index of the next vcall or vbase offset. */
109 /* Nonzero if we are building the initializer for the primary
112 /* Nonzero if we are building the initializer for a construction
115 /* True when adding vcall offset entries to the vtable. False when
116 merely computing the indices. */
117 bool generate_vcall_entries;
120 /* The type of a function passed to walk_subobject_offsets. */
121 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
123 /* The stack itself. This is a dynamically resized array. The
124 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
125 static int current_class_stack_size;
126 static class_stack_node_t current_class_stack;
128 /* The size of the largest empty class seen in this translation unit. */
129 static GTY (()) tree sizeof_biggest_empty_class;
131 /* An array of all local classes present in this translation unit, in
132 declaration order. */
133 vec<tree, va_gc> *local_classes;
135 static tree get_vfield_name (tree);
136 static void finish_struct_anon (tree);
137 static tree get_vtable_name (tree);
138 static void get_basefndecls (tree, tree, vec<tree> *);
139 static int build_primary_vtable (tree, tree);
140 static int build_secondary_vtable (tree);
141 static void finish_vtbls (tree);
142 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
143 static void finish_struct_bits (tree);
144 static int alter_access (tree, tree, tree);
145 static void handle_using_decl (tree, tree);
146 static tree dfs_modify_vtables (tree, void *);
147 static tree modify_all_vtables (tree, tree);
148 static void determine_primary_bases (tree);
149 static void finish_struct_methods (tree);
150 static void maybe_warn_about_overly_private_class (tree);
151 static int method_name_cmp (const void *, const void *);
152 static int resort_method_name_cmp (const void *, const void *);
153 static void add_implicitly_declared_members (tree, tree*, int, int);
154 static tree fixed_type_or_null (tree, int *, int *);
155 static tree build_simple_base_path (tree expr, tree binfo);
156 static tree build_vtbl_ref_1 (tree, tree);
157 static void build_vtbl_initializer (tree, tree, tree, tree, int *,
158 vec<constructor_elt, va_gc> **);
159 static int count_fields (tree);
160 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
161 static void insert_into_classtype_sorted_fields (tree, tree, int);
162 static bool check_bitfield_decl (tree);
163 static void check_field_decl (tree, tree, int *, int *, int *);
164 static void check_field_decls (tree, tree *, int *, int *);
165 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
166 static void build_base_fields (record_layout_info, splay_tree, tree *);
167 static void check_methods (tree);
168 static void remove_zero_width_bit_fields (tree);
169 static bool accessible_nvdtor_p (tree);
170 static void check_bases (tree, int *, int *);
171 static void check_bases_and_members (tree);
172 static tree create_vtable_ptr (tree, tree *);
173 static void include_empty_classes (record_layout_info);
174 static void layout_class_type (tree, tree *);
175 static void propagate_binfo_offsets (tree, tree);
176 static void layout_virtual_bases (record_layout_info, splay_tree);
177 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
178 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
179 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
180 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
181 static void add_vcall_offset (tree, tree, vtbl_init_data *);
182 static void layout_vtable_decl (tree, int);
183 static tree dfs_find_final_overrider_pre (tree, void *);
184 static tree dfs_find_final_overrider_post (tree, void *);
185 static tree find_final_overrider (tree, tree, tree);
186 static int make_new_vtable (tree, tree);
187 static tree get_primary_binfo (tree);
188 static int maybe_indent_hierarchy (FILE *, int, int);
189 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
190 static void dump_class_hierarchy (tree);
191 static void dump_class_hierarchy_1 (FILE *, int, tree);
192 static void dump_array (FILE *, tree);
193 static void dump_vtable (tree, tree, tree);
194 static void dump_vtt (tree, tree);
195 static void dump_thunk (FILE *, int, tree);
196 static tree build_vtable (tree, tree, tree);
197 static void initialize_vtable (tree, vec<constructor_elt, va_gc> *);
198 static void layout_nonempty_base_or_field (record_layout_info,
199 tree, tree, splay_tree);
200 static tree end_of_class (tree, int);
201 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
202 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree,
203 vec<constructor_elt, va_gc> **);
204 static void dfs_accumulate_vtbl_inits (tree, tree, tree, tree, tree,
205 vec<constructor_elt, va_gc> **);
206 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
207 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
208 static void clone_constructors_and_destructors (tree);
209 static tree build_clone (tree, tree);
210 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
211 static void build_ctor_vtbl_group (tree, tree);
212 static void build_vtt (tree);
213 static tree binfo_ctor_vtable (tree);
214 static void build_vtt_inits (tree, tree, vec<constructor_elt, va_gc> **,
216 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
217 static tree dfs_fixup_binfo_vtbls (tree, void *);
218 static int record_subobject_offset (tree, tree, splay_tree);
219 static int check_subobject_offset (tree, tree, splay_tree);
220 static int walk_subobject_offsets (tree, subobject_offset_fn,
221 tree, splay_tree, tree, int);
222 static void record_subobject_offsets (tree, tree, splay_tree, bool);
223 static int layout_conflict_p (tree, tree, splay_tree, int);
224 static int splay_tree_compare_integer_csts (splay_tree_key k1,
226 static void warn_about_ambiguous_bases (tree);
227 static bool type_requires_array_cookie (tree);
228 static bool base_derived_from (tree, tree);
229 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
230 static tree end_of_base (tree);
231 static tree get_vcall_index (tree, tree);
233 /* Variables shared between class.c and call.c. */
236 int n_vtable_entries = 0;
237 int n_vtable_searches = 0;
238 int n_vtable_elems = 0;
239 int n_convert_harshness = 0;
240 int n_compute_conversion_costs = 0;
241 int n_inner_fields_searched = 0;
243 /* Convert to or from a base subobject. EXPR is an expression of type
244 `A' or `A*', an expression of type `B' or `B*' is returned. To
245 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
246 the B base instance within A. To convert base A to derived B, CODE
247 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
248 In this latter case, A must not be a morally virtual base of B.
249 NONNULL is true if EXPR is known to be non-NULL (this is only
250 needed when EXPR is of pointer type). CV qualifiers are preserved
254 build_base_path (enum tree_code code,
258 tsubst_flags_t complain)
260 tree v_binfo = NULL_TREE;
261 tree d_binfo = NULL_TREE;
265 tree null_test = NULL;
266 tree ptr_target_type;
268 int want_pointer = TYPE_PTR_P (TREE_TYPE (expr));
269 bool has_empty = false;
273 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
274 return error_mark_node;
276 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
279 if (is_empty_class (BINFO_TYPE (probe)))
281 if (!v_binfo && BINFO_VIRTUAL_P (probe))
285 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
287 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
289 if (code == PLUS_EXPR
290 && !SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe))
292 /* This can happen when adjust_result_of_qualified_name_lookup can't
293 find a unique base binfo in a call to a member function. We
294 couldn't give the diagnostic then since we might have been calling
295 a static member function, so we do it now. */
296 if (complain & tf_error)
298 tree base = lookup_base (probe, BINFO_TYPE (d_binfo),
299 ba_unique, NULL, complain);
300 gcc_assert (base == error_mark_node);
302 return error_mark_node;
305 gcc_assert ((code == MINUS_EXPR
306 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
307 || code == PLUS_EXPR);
309 if (binfo == d_binfo)
313 if (code == MINUS_EXPR && v_binfo)
315 if (complain & tf_error)
317 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (v_binfo)))
320 error ("cannot convert from pointer to base class %qT to "
321 "pointer to derived class %qT because the base is "
322 "virtual", BINFO_TYPE (binfo), BINFO_TYPE (d_binfo));
324 error ("cannot convert from base class %qT to derived "
325 "class %qT because the base is virtual",
326 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo));
331 error ("cannot convert from pointer to base class %qT to "
332 "pointer to derived class %qT via virtual base %qT",
333 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo),
334 BINFO_TYPE (v_binfo));
336 error ("cannot convert from base class %qT to derived "
337 "class %qT via virtual base %qT", BINFO_TYPE (binfo),
338 BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
341 return error_mark_node;
346 rvalue = !real_lvalue_p (expr);
347 /* This must happen before the call to save_expr. */
348 expr = cp_build_addr_expr (expr, complain);
351 expr = mark_rvalue_use (expr);
353 offset = BINFO_OFFSET (binfo);
354 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
355 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
356 /* TARGET_TYPE has been extracted from BINFO, and, is therefore always
357 cv-unqualified. Extract the cv-qualifiers from EXPR so that the
358 expression returned matches the input. */
359 target_type = cp_build_qualified_type
360 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
361 ptr_target_type = build_pointer_type (target_type);
363 /* Do we need to look in the vtable for the real offset? */
364 virtual_access = (v_binfo && fixed_type_p <= 0);
366 /* Don't bother with the calculations inside sizeof; they'll ICE if the
367 source type is incomplete and the pointer value doesn't matter. In a
368 template (even in instantiate_non_dependent_expr), we don't have vtables
369 set up properly yet, and the value doesn't matter there either; we're
370 just interested in the result of overload resolution. */
371 if (cp_unevaluated_operand != 0
372 || in_template_function ())
374 expr = build_nop (ptr_target_type, expr);
378 /* If we're in an NSDMI, we don't have the full constructor context yet
379 that we need for converting to a virtual base, so just build a stub
380 CONVERT_EXPR and expand it later in bot_replace. */
381 if (virtual_access && fixed_type_p < 0
382 && current_scope () != current_function_decl)
384 expr = build1 (CONVERT_EXPR, ptr_target_type, expr);
385 CONVERT_EXPR_VBASE_PATH (expr) = true;
389 /* Do we need to check for a null pointer? */
390 if (want_pointer && !nonnull)
392 /* If we know the conversion will not actually change the value
393 of EXPR, then we can avoid testing the expression for NULL.
394 We have to avoid generating a COMPONENT_REF for a base class
395 field, because other parts of the compiler know that such
396 expressions are always non-NULL. */
397 if (!virtual_access && integer_zerop (offset))
398 return build_nop (ptr_target_type, expr);
399 null_test = error_mark_node;
402 /* Protect against multiple evaluation if necessary. */
403 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
404 expr = save_expr (expr);
406 /* Now that we've saved expr, build the real null test. */
409 tree zero = cp_convert (TREE_TYPE (expr), nullptr_node, complain);
410 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
414 /* If this is a simple base reference, express it as a COMPONENT_REF. */
415 if (code == PLUS_EXPR && !virtual_access
416 /* We don't build base fields for empty bases, and they aren't very
417 interesting to the optimizers anyway. */
420 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
421 expr = build_simple_base_path (expr, binfo);
425 expr = build_address (expr);
426 target_type = TREE_TYPE (expr);
432 /* Going via virtual base V_BINFO. We need the static offset
433 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
434 V_BINFO. That offset is an entry in D_BINFO's vtable. */
437 if (fixed_type_p < 0 && in_base_initializer)
439 /* In a base member initializer, we cannot rely on the
440 vtable being set up. We have to indirect via the
444 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
445 t = build_pointer_type (t);
446 v_offset = convert (t, current_vtt_parm);
447 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
452 if ((flag_sanitize & SANITIZE_VPTR) && fixed_type_p == 0)
454 t = cp_ubsan_maybe_instrument_cast_to_vbase (input_location,
459 v_offset = build_vfield_ref (cp_build_indirect_ref (t, RO_NULL,
461 TREE_TYPE (TREE_TYPE (expr)));
464 if (v_offset == error_mark_node)
465 return error_mark_node;
467 v_offset = fold_build_pointer_plus (v_offset, BINFO_VPTR_FIELD (v_binfo));
468 v_offset = build1 (NOP_EXPR,
469 build_pointer_type (ptrdiff_type_node),
471 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
472 TREE_CONSTANT (v_offset) = 1;
474 offset = convert_to_integer (ptrdiff_type_node,
475 size_diffop_loc (input_location, offset,
476 BINFO_OFFSET (v_binfo)));
478 if (!integer_zerop (offset))
479 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
481 if (fixed_type_p < 0)
482 /* Negative fixed_type_p means this is a constructor or destructor;
483 virtual base layout is fixed in in-charge [cd]tors, but not in
485 offset = build3 (COND_EXPR, ptrdiff_type_node,
486 build2 (EQ_EXPR, boolean_type_node,
487 current_in_charge_parm, integer_zero_node),
489 convert_to_integer (ptrdiff_type_node,
490 BINFO_OFFSET (binfo)));
496 target_type = ptr_target_type;
498 expr = build1 (NOP_EXPR, ptr_target_type, expr);
500 if (!integer_zerop (offset))
502 offset = fold_convert (sizetype, offset);
503 if (code == MINUS_EXPR)
504 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
505 expr = fold_build_pointer_plus (expr, offset);
513 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
520 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
521 build_zero_cst (target_type));
526 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
527 Perform a derived-to-base conversion by recursively building up a
528 sequence of COMPONENT_REFs to the appropriate base fields. */
531 build_simple_base_path (tree expr, tree binfo)
533 tree type = BINFO_TYPE (binfo);
534 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
537 if (d_binfo == NULL_TREE)
541 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
543 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
544 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
545 an lvalue in the front end; only _DECLs and _REFs are lvalues
547 temp = unary_complex_lvalue (ADDR_EXPR, expr);
549 expr = cp_build_indirect_ref (temp, RO_NULL, tf_warning_or_error);
555 expr = build_simple_base_path (expr, d_binfo);
557 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
558 field; field = DECL_CHAIN (field))
559 /* Is this the base field created by build_base_field? */
560 if (TREE_CODE (field) == FIELD_DECL
561 && DECL_FIELD_IS_BASE (field)
562 && TREE_TYPE (field) == type
563 /* If we're looking for a field in the most-derived class,
564 also check the field offset; we can have two base fields
565 of the same type if one is an indirect virtual base and one
566 is a direct non-virtual base. */
567 && (BINFO_INHERITANCE_CHAIN (d_binfo)
568 || tree_int_cst_equal (byte_position (field),
569 BINFO_OFFSET (binfo))))
571 /* We don't use build_class_member_access_expr here, as that
572 has unnecessary checks, and more importantly results in
573 recursive calls to dfs_walk_once. */
574 int type_quals = cp_type_quals (TREE_TYPE (expr));
576 expr = build3 (COMPONENT_REF,
577 cp_build_qualified_type (type, type_quals),
578 expr, field, NULL_TREE);
579 expr = fold_if_not_in_template (expr);
581 /* Mark the expression const or volatile, as appropriate.
582 Even though we've dealt with the type above, we still have
583 to mark the expression itself. */
584 if (type_quals & TYPE_QUAL_CONST)
585 TREE_READONLY (expr) = 1;
586 if (type_quals & TYPE_QUAL_VOLATILE)
587 TREE_THIS_VOLATILE (expr) = 1;
592 /* Didn't find the base field?!? */
596 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
597 type is a class type or a pointer to a class type. In the former
598 case, TYPE is also a class type; in the latter it is another
599 pointer type. If CHECK_ACCESS is true, an error message is emitted
600 if TYPE is inaccessible. If OBJECT has pointer type, the value is
601 assumed to be non-NULL. */
604 convert_to_base (tree object, tree type, bool check_access, bool nonnull,
605 tsubst_flags_t complain)
610 if (TYPE_PTR_P (TREE_TYPE (object)))
612 object_type = TREE_TYPE (TREE_TYPE (object));
613 type = TREE_TYPE (type);
616 object_type = TREE_TYPE (object);
618 binfo = lookup_base (object_type, type, check_access ? ba_check : ba_unique,
620 if (!binfo || binfo == error_mark_node)
621 return error_mark_node;
623 return build_base_path (PLUS_EXPR, object, binfo, nonnull, complain);
626 /* EXPR is an expression with unqualified class type. BASE is a base
627 binfo of that class type. Returns EXPR, converted to the BASE
628 type. This function assumes that EXPR is the most derived class;
629 therefore virtual bases can be found at their static offsets. */
632 convert_to_base_statically (tree expr, tree base)
636 expr_type = TREE_TYPE (expr);
637 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
639 /* If this is a non-empty base, use a COMPONENT_REF. */
640 if (!is_empty_class (BINFO_TYPE (base)))
641 return build_simple_base_path (expr, base);
643 /* We use fold_build2 and fold_convert below to simplify the trees
644 provided to the optimizers. It is not safe to call these functions
645 when processing a template because they do not handle C++-specific
647 gcc_assert (!processing_template_decl);
648 expr = cp_build_addr_expr (expr, tf_warning_or_error);
649 if (!integer_zerop (BINFO_OFFSET (base)))
650 expr = fold_build_pointer_plus_loc (input_location,
651 expr, BINFO_OFFSET (base));
652 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
653 expr = build_fold_indirect_ref_loc (input_location, expr);
661 build_vfield_ref (tree datum, tree type)
663 tree vfield, vcontext;
665 if (datum == error_mark_node
666 /* Can happen in case of duplicate base types (c++/59082). */
667 || !TYPE_VFIELD (type))
668 return error_mark_node;
670 /* First, convert to the requested type. */
671 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
672 datum = convert_to_base (datum, type, /*check_access=*/false,
673 /*nonnull=*/true, tf_warning_or_error);
675 /* Second, the requested type may not be the owner of its own vptr.
676 If not, convert to the base class that owns it. We cannot use
677 convert_to_base here, because VCONTEXT may appear more than once
678 in the inheritance hierarchy of TYPE, and thus direct conversion
679 between the types may be ambiguous. Following the path back up
680 one step at a time via primary bases avoids the problem. */
681 vfield = TYPE_VFIELD (type);
682 vcontext = DECL_CONTEXT (vfield);
683 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
685 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
686 type = TREE_TYPE (datum);
689 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
692 /* Given an object INSTANCE, return an expression which yields the
693 vtable element corresponding to INDEX. There are many special
694 cases for INSTANCE which we take care of here, mainly to avoid
695 creating extra tree nodes when we don't have to. */
698 build_vtbl_ref_1 (tree instance, tree idx)
701 tree vtbl = NULL_TREE;
703 /* Try to figure out what a reference refers to, and
704 access its virtual function table directly. */
707 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
709 tree basetype = non_reference (TREE_TYPE (instance));
711 if (fixed_type && !cdtorp)
713 tree binfo = lookup_base (fixed_type, basetype,
714 ba_unique, NULL, tf_none);
715 if (binfo && binfo != error_mark_node)
716 vtbl = unshare_expr (BINFO_VTABLE (binfo));
720 vtbl = build_vfield_ref (instance, basetype);
722 aref = build_array_ref (input_location, vtbl, idx);
723 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
729 build_vtbl_ref (tree instance, tree idx)
731 tree aref = build_vtbl_ref_1 (instance, idx);
736 /* Given a stable object pointer INSTANCE_PTR, return an expression which
737 yields a function pointer corresponding to vtable element INDEX. */
740 build_vfn_ref (tree instance_ptr, tree idx)
744 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, RO_NULL,
745 tf_warning_or_error),
748 /* When using function descriptors, the address of the
749 vtable entry is treated as a function pointer. */
750 if (TARGET_VTABLE_USES_DESCRIPTORS)
751 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
752 cp_build_addr_expr (aref, tf_warning_or_error));
754 /* Remember this as a method reference, for later devirtualization. */
755 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
760 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
761 for the given TYPE. */
764 get_vtable_name (tree type)
766 return mangle_vtbl_for_type (type);
769 /* DECL is an entity associated with TYPE, like a virtual table or an
770 implicitly generated constructor. Determine whether or not DECL
771 should have external or internal linkage at the object file
772 level. This routine does not deal with COMDAT linkage and other
773 similar complexities; it simply sets TREE_PUBLIC if it possible for
774 entities in other translation units to contain copies of DECL, in
778 set_linkage_according_to_type (tree /*type*/, tree decl)
780 TREE_PUBLIC (decl) = 1;
781 determine_visibility (decl);
784 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
785 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
786 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
789 build_vtable (tree class_type, tree name, tree vtable_type)
793 decl = build_lang_decl (VAR_DECL, name, vtable_type);
794 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
795 now to avoid confusion in mangle_decl. */
796 SET_DECL_ASSEMBLER_NAME (decl, name);
797 DECL_CONTEXT (decl) = class_type;
798 DECL_ARTIFICIAL (decl) = 1;
799 TREE_STATIC (decl) = 1;
800 TREE_READONLY (decl) = 1;
801 DECL_VIRTUAL_P (decl) = 1;
802 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
803 DECL_USER_ALIGN (decl) = true;
804 DECL_VTABLE_OR_VTT_P (decl) = 1;
805 set_linkage_according_to_type (class_type, decl);
806 /* The vtable has not been defined -- yet. */
807 DECL_EXTERNAL (decl) = 1;
808 DECL_NOT_REALLY_EXTERN (decl) = 1;
810 /* Mark the VAR_DECL node representing the vtable itself as a
811 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
812 is rather important that such things be ignored because any
813 effort to actually generate DWARF for them will run into
814 trouble when/if we encounter code like:
817 struct S { virtual void member (); };
819 because the artificial declaration of the vtable itself (as
820 manufactured by the g++ front end) will say that the vtable is
821 a static member of `S' but only *after* the debug output for
822 the definition of `S' has already been output. This causes
823 grief because the DWARF entry for the definition of the vtable
824 will try to refer back to an earlier *declaration* of the
825 vtable as a static member of `S' and there won't be one. We
826 might be able to arrange to have the "vtable static member"
827 attached to the member list for `S' before the debug info for
828 `S' get written (which would solve the problem) but that would
829 require more intrusive changes to the g++ front end. */
830 DECL_IGNORED_P (decl) = 1;
835 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
836 or even complete. If this does not exist, create it. If COMPLETE is
837 nonzero, then complete the definition of it -- that will render it
838 impossible to actually build the vtable, but is useful to get at those
839 which are known to exist in the runtime. */
842 get_vtable_decl (tree type, int complete)
846 if (CLASSTYPE_VTABLES (type))
847 return CLASSTYPE_VTABLES (type);
849 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
850 CLASSTYPE_VTABLES (type) = decl;
854 DECL_EXTERNAL (decl) = 1;
855 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
861 /* Build the primary virtual function table for TYPE. If BINFO is
862 non-NULL, build the vtable starting with the initial approximation
863 that it is the same as the one which is the head of the association
864 list. Returns a nonzero value if a new vtable is actually
868 build_primary_vtable (tree binfo, tree type)
873 decl = get_vtable_decl (type, /*complete=*/0);
877 if (BINFO_NEW_VTABLE_MARKED (binfo))
878 /* We have already created a vtable for this base, so there's
879 no need to do it again. */
882 virtuals = copy_list (BINFO_VIRTUALS (binfo));
883 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
884 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
885 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
889 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
890 virtuals = NULL_TREE;
893 if (GATHER_STATISTICS)
896 n_vtable_elems += list_length (virtuals);
899 /* Initialize the association list for this type, based
900 on our first approximation. */
901 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
902 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
903 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
907 /* Give BINFO a new virtual function table which is initialized
908 with a skeleton-copy of its original initialization. The only
909 entry that changes is the `delta' entry, so we can really
910 share a lot of structure.
912 FOR_TYPE is the most derived type which caused this table to
915 Returns nonzero if we haven't met BINFO before.
917 The order in which vtables are built (by calling this function) for
918 an object must remain the same, otherwise a binary incompatibility
922 build_secondary_vtable (tree binfo)
924 if (BINFO_NEW_VTABLE_MARKED (binfo))
925 /* We already created a vtable for this base. There's no need to
929 /* Remember that we've created a vtable for this BINFO, so that we
930 don't try to do so again. */
931 SET_BINFO_NEW_VTABLE_MARKED (binfo);
933 /* Make fresh virtual list, so we can smash it later. */
934 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
936 /* Secondary vtables are laid out as part of the same structure as
937 the primary vtable. */
938 BINFO_VTABLE (binfo) = NULL_TREE;
942 /* Create a new vtable for BINFO which is the hierarchy dominated by
943 T. Return nonzero if we actually created a new vtable. */
946 make_new_vtable (tree t, tree binfo)
948 if (binfo == TYPE_BINFO (t))
949 /* In this case, it is *type*'s vtable we are modifying. We start
950 with the approximation that its vtable is that of the
951 immediate base class. */
952 return build_primary_vtable (binfo, t);
954 /* This is our very own copy of `basetype' to play with. Later,
955 we will fill in all the virtual functions that override the
956 virtual functions in these base classes which are not defined
957 by the current type. */
958 return build_secondary_vtable (binfo);
961 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
962 (which is in the hierarchy dominated by T) list FNDECL as its
963 BV_FN. DELTA is the required constant adjustment from the `this'
964 pointer where the vtable entry appears to the `this' required when
965 the function is actually called. */
968 modify_vtable_entry (tree t,
978 if (fndecl != BV_FN (v)
979 || !tree_int_cst_equal (delta, BV_DELTA (v)))
981 /* We need a new vtable for BINFO. */
982 if (make_new_vtable (t, binfo))
984 /* If we really did make a new vtable, we also made a copy
985 of the BINFO_VIRTUALS list. Now, we have to find the
986 corresponding entry in that list. */
987 *virtuals = BINFO_VIRTUALS (binfo);
988 while (BV_FN (*virtuals) != BV_FN (v))
989 *virtuals = TREE_CHAIN (*virtuals);
993 BV_DELTA (v) = delta;
994 BV_VCALL_INDEX (v) = NULL_TREE;
1000 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
1001 the USING_DECL naming METHOD. Returns true if the method could be
1002 added to the method vec. */
1005 add_method (tree type, tree method, tree using_decl)
1009 bool template_conv_p = false;
1011 vec<tree, va_gc> *method_vec;
1013 bool insert_p = false;
1017 if (method == error_mark_node)
1020 complete_p = COMPLETE_TYPE_P (type);
1021 conv_p = DECL_CONV_FN_P (method);
1023 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
1024 && DECL_TEMPLATE_CONV_FN_P (method));
1026 method_vec = CLASSTYPE_METHOD_VEC (type);
1029 /* Make a new method vector. We start with 8 entries. We must
1030 allocate at least two (for constructors and destructors), and
1031 we're going to end up with an assignment operator at some
1033 vec_alloc (method_vec, 8);
1034 /* Create slots for constructors and destructors. */
1035 method_vec->quick_push (NULL_TREE);
1036 method_vec->quick_push (NULL_TREE);
1037 CLASSTYPE_METHOD_VEC (type) = method_vec;
1040 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
1041 grok_special_member_properties (method);
1043 /* Constructors and destructors go in special slots. */
1044 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
1045 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
1046 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1048 slot = CLASSTYPE_DESTRUCTOR_SLOT;
1050 if (TYPE_FOR_JAVA (type))
1052 if (!DECL_ARTIFICIAL (method))
1053 error ("Java class %qT cannot have a destructor", type);
1054 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
1055 error ("Java class %qT cannot have an implicit non-trivial "
1065 /* See if we already have an entry with this name. */
1066 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1067 vec_safe_iterate (method_vec, slot, &m);
1070 m = OVL_CURRENT (m);
1071 if (template_conv_p)
1073 if (TREE_CODE (m) == TEMPLATE_DECL
1074 && DECL_TEMPLATE_CONV_FN_P (m))
1078 if (conv_p && !DECL_CONV_FN_P (m))
1080 if (DECL_NAME (m) == DECL_NAME (method))
1086 && !DECL_CONV_FN_P (m)
1087 && DECL_NAME (m) > DECL_NAME (method))
1091 current_fns = insert_p ? NULL_TREE : (*method_vec)[slot];
1093 /* Check to see if we've already got this method. */
1094 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1096 tree fn = OVL_CURRENT (fns);
1102 if (TREE_CODE (fn) != TREE_CODE (method))
1105 /* [over.load] Member function declarations with the
1106 same name and the same parameter types cannot be
1107 overloaded if any of them is a static member
1108 function declaration.
1110 [over.load] Member function declarations with the same name and
1111 the same parameter-type-list as well as member function template
1112 declarations with the same name, the same parameter-type-list, and
1113 the same template parameter lists cannot be overloaded if any of
1114 them, but not all, have a ref-qualifier.
1116 [namespace.udecl] When a using-declaration brings names
1117 from a base class into a derived class scope, member
1118 functions in the derived class override and/or hide member
1119 functions with the same name and parameter types in a base
1120 class (rather than conflicting). */
1121 fn_type = TREE_TYPE (fn);
1122 method_type = TREE_TYPE (method);
1123 parms1 = TYPE_ARG_TYPES (fn_type);
1124 parms2 = TYPE_ARG_TYPES (method_type);
1126 /* Compare the quals on the 'this' parm. Don't compare
1127 the whole types, as used functions are treated as
1128 coming from the using class in overload resolution. */
1129 if (! DECL_STATIC_FUNCTION_P (fn)
1130 && ! DECL_STATIC_FUNCTION_P (method)
1131 /* Either both or neither need to be ref-qualified for
1132 differing quals to allow overloading. */
1133 && (FUNCTION_REF_QUALIFIED (fn_type)
1134 == FUNCTION_REF_QUALIFIED (method_type))
1135 && (type_memfn_quals (fn_type) != type_memfn_quals (method_type)
1136 || type_memfn_rqual (fn_type) != type_memfn_rqual (method_type)))
1139 /* For templates, the return type and template parameters
1140 must be identical. */
1141 if (TREE_CODE (fn) == TEMPLATE_DECL
1142 && (!same_type_p (TREE_TYPE (fn_type),
1143 TREE_TYPE (method_type))
1144 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1145 DECL_TEMPLATE_PARMS (method))))
1148 if (! DECL_STATIC_FUNCTION_P (fn))
1149 parms1 = TREE_CHAIN (parms1);
1150 if (! DECL_STATIC_FUNCTION_P (method))
1151 parms2 = TREE_CHAIN (parms2);
1153 if (compparms (parms1, parms2)
1154 && (!DECL_CONV_FN_P (fn)
1155 || same_type_p (TREE_TYPE (fn_type),
1156 TREE_TYPE (method_type))))
1158 /* For function versions, their parms and types match
1159 but they are not duplicates. Record function versions
1160 as and when they are found. extern "C" functions are
1161 not treated as versions. */
1162 if (TREE_CODE (fn) == FUNCTION_DECL
1163 && TREE_CODE (method) == FUNCTION_DECL
1164 && !DECL_EXTERN_C_P (fn)
1165 && !DECL_EXTERN_C_P (method)
1166 && targetm.target_option.function_versions (fn, method))
1168 /* Mark functions as versions if necessary. Modify the mangled
1169 decl name if necessary. */
1170 if (!DECL_FUNCTION_VERSIONED (fn))
1172 DECL_FUNCTION_VERSIONED (fn) = 1;
1173 if (DECL_ASSEMBLER_NAME_SET_P (fn))
1176 if (!DECL_FUNCTION_VERSIONED (method))
1178 DECL_FUNCTION_VERSIONED (method) = 1;
1179 if (DECL_ASSEMBLER_NAME_SET_P (method))
1180 mangle_decl (method);
1182 cgraph_node::record_function_versions (fn, method);
1185 if (DECL_INHERITED_CTOR_BASE (method))
1187 if (DECL_INHERITED_CTOR_BASE (fn))
1189 error_at (DECL_SOURCE_LOCATION (method),
1190 "%q#D inherited from %qT", method,
1191 DECL_INHERITED_CTOR_BASE (method));
1192 error_at (DECL_SOURCE_LOCATION (fn),
1193 "conflicts with version inherited from %qT",
1194 DECL_INHERITED_CTOR_BASE (fn));
1196 /* Otherwise defer to the other function. */
1201 if (DECL_CONTEXT (fn) == type)
1202 /* Defer to the local function. */
1207 error ("%q+#D cannot be overloaded", method);
1208 error ("with %q+#D", fn);
1211 /* We don't call duplicate_decls here to merge the
1212 declarations because that will confuse things if the
1213 methods have inline definitions. In particular, we
1214 will crash while processing the definitions. */
1219 /* A class should never have more than one destructor. */
1220 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1223 /* Add the new binding. */
1226 overload = ovl_cons (method, current_fns);
1227 OVL_USED (overload) = true;
1230 overload = build_overload (method, current_fns);
1233 TYPE_HAS_CONVERSION (type) = 1;
1234 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1235 push_class_level_binding (DECL_NAME (method), overload);
1241 /* We only expect to add few methods in the COMPLETE_P case, so
1242 just make room for one more method in that case. */
1244 reallocated = vec_safe_reserve_exact (method_vec, 1);
1246 reallocated = vec_safe_reserve (method_vec, 1);
1248 CLASSTYPE_METHOD_VEC (type) = method_vec;
1249 if (slot == method_vec->length ())
1250 method_vec->quick_push (overload);
1252 method_vec->quick_insert (slot, overload);
1255 /* Replace the current slot. */
1256 (*method_vec)[slot] = overload;
1260 /* Subroutines of finish_struct. */
1262 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1263 legit, otherwise return 0. */
1266 alter_access (tree t, tree fdecl, tree access)
1270 if (!DECL_LANG_SPECIFIC (fdecl))
1271 retrofit_lang_decl (fdecl);
1273 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1275 elem = purpose_member (t, DECL_ACCESS (fdecl));
1278 if (TREE_VALUE (elem) != access)
1280 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1281 error ("conflicting access specifications for method"
1282 " %q+D, ignored", TREE_TYPE (fdecl));
1284 error ("conflicting access specifications for field %qE, ignored",
1289 /* They're changing the access to the same thing they changed
1290 it to before. That's OK. */
1296 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl,
1297 tf_warning_or_error);
1298 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1304 /* Process the USING_DECL, which is a member of T. */
1307 handle_using_decl (tree using_decl, tree t)
1309 tree decl = USING_DECL_DECLS (using_decl);
1310 tree name = DECL_NAME (using_decl);
1312 = TREE_PRIVATE (using_decl) ? access_private_node
1313 : TREE_PROTECTED (using_decl) ? access_protected_node
1314 : access_public_node;
1315 tree flist = NULL_TREE;
1318 gcc_assert (!processing_template_decl && decl);
1320 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false,
1321 tf_warning_or_error);
1324 if (is_overloaded_fn (old_value))
1325 old_value = OVL_CURRENT (old_value);
1327 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1330 old_value = NULL_TREE;
1333 cp_emit_debug_info_for_using (decl, t);
1335 if (is_overloaded_fn (decl))
1340 else if (is_overloaded_fn (old_value))
1343 /* It's OK to use functions from a base when there are functions with
1344 the same name already present in the current class. */;
1347 error ("%q+D invalid in %q#T", using_decl, t);
1348 error (" because of local method %q+#D with same name",
1349 OVL_CURRENT (old_value));
1353 else if (!DECL_ARTIFICIAL (old_value))
1355 error ("%q+D invalid in %q#T", using_decl, t);
1356 error (" because of local member %q+#D with same name", old_value);
1360 /* Make type T see field decl FDECL with access ACCESS. */
1362 for (; flist; flist = OVL_NEXT (flist))
1364 add_method (t, OVL_CURRENT (flist), using_decl);
1365 alter_access (t, OVL_CURRENT (flist), access);
1368 alter_access (t, decl, access);
1371 /* Data structure for find_abi_tags_r, below. */
1375 tree t; // The type that we're checking for missing tags.
1376 tree subob; // The subobject of T that we're getting tags from.
1377 tree tags; // error_mark_node for diagnostics, or a list of missing tags.
1380 /* Subroutine of find_abi_tags_r. Handle a single TAG found on the class TP
1381 in the context of P. TAG can be either an identifier (the DECL_NAME of
1382 a tag NAMESPACE_DECL) or a STRING_CST (a tag attribute). */
1385 check_tag (tree tag, tree id, tree *tp, abi_tag_data *p)
1387 if (!IDENTIFIER_MARKED (id))
1389 if (p->tags != error_mark_node)
1391 /* We're collecting tags from template arguments or from
1392 the type of a variable or function return type. */
1393 p->tags = tree_cons (NULL_TREE, tag, p->tags);
1395 /* Don't inherit this tag multiple times. */
1396 IDENTIFIER_MARKED (id) = true;
1400 /* Tags inherited from type template arguments are only used
1401 to avoid warnings. */
1402 ABI_TAG_IMPLICIT (p->tags) = true;
1405 /* For functions and variables we want to warn, too. */
1408 /* Otherwise we're diagnosing missing tags. */
1409 if (TREE_CODE (p->t) == FUNCTION_DECL)
1411 if (warning (OPT_Wabi_tag, "%qD inherits the %E ABI tag "
1412 "that %qT (used in its return type) has",
1414 inform (location_of (*tp), "%qT declared here", *tp);
1416 else if (TREE_CODE (p->t) == VAR_DECL)
1418 if (warning (OPT_Wabi_tag, "%qD inherits the %E ABI tag "
1419 "that %qT (used in its type) has", p->t, tag, *tp))
1420 inform (location_of (*tp), "%qT declared here", *tp);
1422 else if (TYPE_P (p->subob))
1424 if (warning (OPT_Wabi_tag, "%qT does not have the %E ABI tag "
1425 "that base %qT has", p->t, tag, p->subob))
1426 inform (location_of (p->subob), "%qT declared here",
1431 if (warning (OPT_Wabi_tag, "%qT does not have the %E ABI tag "
1432 "that %qT (used in the type of %qD) has",
1433 p->t, tag, *tp, p->subob))
1435 inform (location_of (p->subob), "%qD declared here",
1437 inform (location_of (*tp), "%qT declared here", *tp);
1443 /* Find all the ABI tags in the attribute list ATTR and either call
1444 check_tag (if TP is non-null) or set IDENTIFIER_MARKED to val. */
1447 mark_or_check_attr_tags (tree attr, tree *tp, abi_tag_data *p, bool val)
1451 for (; (attr = lookup_attribute ("abi_tag", attr));
1452 attr = TREE_CHAIN (attr))
1453 for (tree list = TREE_VALUE (attr); list;
1454 list = TREE_CHAIN (list))
1456 tree tag = TREE_VALUE (list);
1457 tree id = get_identifier (TREE_STRING_POINTER (tag));
1459 check_tag (tag, id, tp, p);
1461 IDENTIFIER_MARKED (id) = val;
1465 /* Find all the ABI tags on T and its enclosing scopes and either call
1466 check_tag (if TP is non-null) or set IDENTIFIER_MARKED to val. */
1469 mark_or_check_tags (tree t, tree *tp, abi_tag_data *p, bool val)
1471 while (t != global_namespace)
1476 attr = TYPE_ATTRIBUTES (t);
1477 t = CP_TYPE_CONTEXT (t);
1481 attr = DECL_ATTRIBUTES (t);
1482 t = CP_DECL_CONTEXT (t);
1484 mark_or_check_attr_tags (attr, tp, p, val);
1488 /* walk_tree callback for check_abi_tags: if the type at *TP involves any
1489 types with ABI tags, add the corresponding identifiers to the VEC in
1490 *DATA and set IDENTIFIER_MARKED. */
1493 find_abi_tags_r (tree *tp, int *walk_subtrees, void *data)
1495 if (!OVERLOAD_TYPE_P (*tp))
1498 /* walk_tree shouldn't be walking into any subtrees of a RECORD_TYPE
1499 anyway, but let's make sure of it. */
1500 *walk_subtrees = false;
1502 abi_tag_data *p = static_cast<struct abi_tag_data*>(data);
1504 mark_or_check_tags (*tp, tp, p, false);
1509 /* walk_tree callback for mark_abi_tags: if *TP is a class, set
1510 IDENTIFIER_MARKED on its ABI tags. */
1513 mark_abi_tags_r (tree *tp, int *walk_subtrees, void *data)
1515 if (!OVERLOAD_TYPE_P (*tp))
1518 /* walk_tree shouldn't be walking into any subtrees of a RECORD_TYPE
1519 anyway, but let's make sure of it. */
1520 *walk_subtrees = false;
1522 bool *valp = static_cast<bool*>(data);
1524 mark_or_check_tags (*tp, NULL, NULL, *valp);
1529 /* Set IDENTIFIER_MARKED on all the ABI tags on T and its enclosing
1533 mark_abi_tags (tree t, bool val)
1535 mark_or_check_tags (t, NULL, NULL, val);
1538 if (DECL_LANG_SPECIFIC (t) && DECL_USE_TEMPLATE (t)
1539 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t)))
1541 /* Template arguments are part of the signature. */
1542 tree level = INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (t));
1543 for (int j = 0; j < TREE_VEC_LENGTH (level); ++j)
1545 tree arg = TREE_VEC_ELT (level, j);
1546 cp_walk_tree_without_duplicates (&arg, mark_abi_tags_r, &val);
1549 if (TREE_CODE (t) == FUNCTION_DECL)
1550 /* A function's parameter types are part of the signature, so
1551 we don't need to inherit any tags that are also in them. */
1552 for (tree arg = FUNCTION_FIRST_USER_PARMTYPE (t); arg;
1553 arg = TREE_CHAIN (arg))
1554 cp_walk_tree_without_duplicates (&TREE_VALUE (arg),
1555 mark_abi_tags_r, &val);
1559 /* Check that T has all the ABI tags that subobject SUBOB has, or
1560 warn if not. If T is a (variable or function) declaration, also
1561 add any missing tags. */
1564 check_abi_tags (tree t, tree subob)
1566 bool inherit = DECL_P (t);
1568 if (!inherit && !warn_abi_tag)
1571 tree decl = TYPE_P (t) ? TYPE_NAME (t) : t;
1572 if (!TREE_PUBLIC (decl))
1573 /* No need to worry about things local to this TU. */
1576 mark_abi_tags (t, true);
1578 tree subtype = TYPE_P (subob) ? subob : TREE_TYPE (subob);
1579 struct abi_tag_data data = { t, subob, error_mark_node };
1581 data.tags = NULL_TREE;
1583 cp_walk_tree_without_duplicates (&subtype, find_abi_tags_r, &data);
1585 if (inherit && data.tags)
1587 tree attr = lookup_attribute ("abi_tag", DECL_ATTRIBUTES (t));
1589 TREE_VALUE (attr) = chainon (data.tags, TREE_VALUE (attr));
1592 = tree_cons (get_identifier ("abi_tag"), data.tags,
1593 DECL_ATTRIBUTES (t));
1596 mark_abi_tags (t, false);
1599 /* Check that DECL has all the ABI tags that are used in parts of its type
1600 that are not reflected in its mangled name. */
1603 check_abi_tags (tree decl)
1605 if (TREE_CODE (decl) == VAR_DECL)
1606 check_abi_tags (decl, TREE_TYPE (decl));
1607 else if (TREE_CODE (decl) == FUNCTION_DECL
1608 && !mangle_return_type_p (decl))
1609 check_abi_tags (decl, TREE_TYPE (TREE_TYPE (decl)));
1613 inherit_targ_abi_tags (tree t)
1615 if (!CLASS_TYPE_P (t)
1616 || CLASSTYPE_TEMPLATE_INFO (t) == NULL_TREE)
1619 mark_abi_tags (t, true);
1621 tree args = CLASSTYPE_TI_ARGS (t);
1622 struct abi_tag_data data = { t, NULL_TREE, NULL_TREE };
1623 for (int i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
1625 tree level = TMPL_ARGS_LEVEL (args, i+1);
1626 for (int j = 0; j < TREE_VEC_LENGTH (level); ++j)
1628 tree arg = TREE_VEC_ELT (level, j);
1630 cp_walk_tree_without_duplicates (&arg, find_abi_tags_r, &data);
1634 // If we found some tags on our template arguments, add them to our
1635 // abi_tag attribute.
1638 tree attr = lookup_attribute ("abi_tag", TYPE_ATTRIBUTES (t));
1640 TREE_VALUE (attr) = chainon (data.tags, TREE_VALUE (attr));
1643 = tree_cons (get_identifier ("abi_tag"), data.tags,
1644 TYPE_ATTRIBUTES (t));
1647 mark_abi_tags (t, false);
1650 /* Return true, iff class T has a non-virtual destructor that is
1651 accessible from outside the class heirarchy (i.e. is public, or
1652 there's a suitable friend. */
1655 accessible_nvdtor_p (tree t)
1657 tree dtor = CLASSTYPE_DESTRUCTORS (t);
1659 /* An implicitly declared destructor is always public. And,
1660 if it were virtual, we would have created it by now. */
1664 if (DECL_VINDEX (dtor))
1665 return false; /* Virtual */
1667 if (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
1668 return true; /* Public */
1670 if (CLASSTYPE_FRIEND_CLASSES (t)
1671 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1672 return true; /* Has friends */
1677 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1678 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1679 properties of the bases. */
1682 check_bases (tree t,
1683 int* cant_have_const_ctor_p,
1684 int* no_const_asn_ref_p)
1687 bool seen_non_virtual_nearly_empty_base_p = 0;
1688 int seen_tm_mask = 0;
1691 tree field = NULL_TREE;
1693 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1694 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
1695 if (TREE_CODE (field) == FIELD_DECL)
1698 for (binfo = TYPE_BINFO (t), i = 0;
1699 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1701 tree basetype = TREE_TYPE (base_binfo);
1703 gcc_assert (COMPLETE_TYPE_P (basetype));
1705 if (CLASSTYPE_FINAL (basetype))
1706 error ("cannot derive from %<final%> base %qT in derived type %qT",
1709 /* If any base class is non-literal, so is the derived class. */
1710 if (!CLASSTYPE_LITERAL_P (basetype))
1711 CLASSTYPE_LITERAL_P (t) = false;
1713 /* If the base class doesn't have copy constructors or
1714 assignment operators that take const references, then the
1715 derived class cannot have such a member automatically
1717 if (TYPE_HAS_COPY_CTOR (basetype)
1718 && ! TYPE_HAS_CONST_COPY_CTOR (basetype))
1719 *cant_have_const_ctor_p = 1;
1720 if (TYPE_HAS_COPY_ASSIGN (basetype)
1721 && !TYPE_HAS_CONST_COPY_ASSIGN (basetype))
1722 *no_const_asn_ref_p = 1;
1724 if (BINFO_VIRTUAL_P (base_binfo))
1725 /* A virtual base does not effect nearly emptiness. */
1727 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1729 if (seen_non_virtual_nearly_empty_base_p)
1730 /* And if there is more than one nearly empty base, then the
1731 derived class is not nearly empty either. */
1732 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1734 /* Remember we've seen one. */
1735 seen_non_virtual_nearly_empty_base_p = 1;
1737 else if (!is_empty_class (basetype))
1738 /* If the base class is not empty or nearly empty, then this
1739 class cannot be nearly empty. */
1740 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1742 /* A lot of properties from the bases also apply to the derived
1744 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1745 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1746 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1747 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
1748 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (basetype)
1749 || !TYPE_HAS_COPY_ASSIGN (basetype));
1750 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (basetype)
1751 || !TYPE_HAS_COPY_CTOR (basetype));
1752 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t)
1753 |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (basetype);
1754 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (basetype);
1755 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1756 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1757 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1758 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
1759 || TYPE_HAS_COMPLEX_DFLT (basetype));
1760 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT
1761 (t, CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
1762 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (basetype));
1763 SET_CLASSTYPE_REF_FIELDS_NEED_INIT
1764 (t, CLASSTYPE_REF_FIELDS_NEED_INIT (t)
1765 | CLASSTYPE_REF_FIELDS_NEED_INIT (basetype));
1767 /* A standard-layout class is a class that:
1769 * has no non-standard-layout base classes, */
1770 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1771 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1774 /* ...has no base classes of the same type as the first non-static
1776 if (field && DECL_CONTEXT (field) == t
1777 && (same_type_ignoring_top_level_qualifiers_p
1778 (TREE_TYPE (field), basetype)))
1779 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1781 /* ...either has no non-static data members in the most-derived
1782 class and at most one base class with non-static data
1783 members, or has no base classes with non-static data
1785 for (basefield = TYPE_FIELDS (basetype); basefield;
1786 basefield = DECL_CHAIN (basefield))
1787 if (TREE_CODE (basefield) == FIELD_DECL)
1790 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1797 /* Don't bother collecting tm attributes if transactional memory
1798 support is not enabled. */
1801 tree tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (basetype));
1803 seen_tm_mask |= tm_attr_to_mask (tm_attr);
1806 check_abi_tags (t, basetype);
1809 /* If one of the base classes had TM attributes, and the current class
1810 doesn't define its own, then the current class inherits one. */
1811 if (seen_tm_mask && !find_tm_attribute (TYPE_ATTRIBUTES (t)))
1813 tree tm_attr = tm_mask_to_attr (seen_tm_mask & -seen_tm_mask);
1814 TYPE_ATTRIBUTES (t) = tree_cons (tm_attr, NULL, TYPE_ATTRIBUTES (t));
1818 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1819 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1820 that have had a nearly-empty virtual primary base stolen by some
1821 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1825 determine_primary_bases (tree t)
1828 tree primary = NULL_TREE;
1829 tree type_binfo = TYPE_BINFO (t);
1832 /* Determine the primary bases of our bases. */
1833 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1834 base_binfo = TREE_CHAIN (base_binfo))
1836 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1838 /* See if we're the non-virtual primary of our inheritance
1840 if (!BINFO_VIRTUAL_P (base_binfo))
1842 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1843 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1846 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1847 BINFO_TYPE (parent_primary)))
1848 /* We are the primary binfo. */
1849 BINFO_PRIMARY_P (base_binfo) = 1;
1851 /* Determine if we have a virtual primary base, and mark it so.
1853 if (primary && BINFO_VIRTUAL_P (primary))
1855 tree this_primary = copied_binfo (primary, base_binfo);
1857 if (BINFO_PRIMARY_P (this_primary))
1858 /* Someone already claimed this base. */
1859 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1864 BINFO_PRIMARY_P (this_primary) = 1;
1865 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1867 /* A virtual binfo might have been copied from within
1868 another hierarchy. As we're about to use it as a
1869 primary base, make sure the offsets match. */
1870 delta = size_diffop_loc (input_location,
1872 BINFO_OFFSET (base_binfo)),
1874 BINFO_OFFSET (this_primary)));
1876 propagate_binfo_offsets (this_primary, delta);
1881 /* First look for a dynamic direct non-virtual base. */
1882 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1884 tree basetype = BINFO_TYPE (base_binfo);
1886 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1888 primary = base_binfo;
1893 /* A "nearly-empty" virtual base class can be the primary base
1894 class, if no non-virtual polymorphic base can be found. Look for
1895 a nearly-empty virtual dynamic base that is not already a primary
1896 base of something in the hierarchy. If there is no such base,
1897 just pick the first nearly-empty virtual base. */
1899 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1900 base_binfo = TREE_CHAIN (base_binfo))
1901 if (BINFO_VIRTUAL_P (base_binfo)
1902 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1904 if (!BINFO_PRIMARY_P (base_binfo))
1906 /* Found one that is not primary. */
1907 primary = base_binfo;
1911 /* Remember the first candidate. */
1912 primary = base_binfo;
1916 /* If we've got a primary base, use it. */
1919 tree basetype = BINFO_TYPE (primary);
1921 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1922 if (BINFO_PRIMARY_P (primary))
1923 /* We are stealing a primary base. */
1924 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1925 BINFO_PRIMARY_P (primary) = 1;
1926 if (BINFO_VIRTUAL_P (primary))
1930 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1931 /* A virtual binfo might have been copied from within
1932 another hierarchy. As we're about to use it as a primary
1933 base, make sure the offsets match. */
1934 delta = size_diffop_loc (input_location, ssize_int (0),
1935 convert (ssizetype, BINFO_OFFSET (primary)));
1937 propagate_binfo_offsets (primary, delta);
1940 primary = TYPE_BINFO (basetype);
1942 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1943 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1944 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1948 /* Update the variant types of T. */
1951 fixup_type_variants (tree t)
1958 for (variants = TYPE_NEXT_VARIANT (t);
1960 variants = TYPE_NEXT_VARIANT (variants))
1962 /* These fields are in the _TYPE part of the node, not in
1963 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1964 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1965 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1966 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1967 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1969 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1971 TYPE_BINFO (variants) = TYPE_BINFO (t);
1973 /* Copy whatever these are holding today. */
1974 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1975 TYPE_METHODS (variants) = TYPE_METHODS (t);
1976 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1980 /* Early variant fixups: we apply attributes at the beginning of the class
1981 definition, and we need to fix up any variants that have already been
1982 made via elaborated-type-specifier so that check_qualified_type works. */
1985 fixup_attribute_variants (tree t)
1992 for (variants = TYPE_NEXT_VARIANT (t);
1994 variants = TYPE_NEXT_VARIANT (variants))
1996 /* These are the two fields that check_qualified_type looks at and
1997 are affected by attributes. */
1998 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1999 TYPE_ALIGN (variants) = TYPE_ALIGN (t);
2003 /* Set memoizing fields and bits of T (and its variants) for later
2007 finish_struct_bits (tree t)
2009 /* Fix up variants (if any). */
2010 fixup_type_variants (t);
2012 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
2013 /* For a class w/o baseclasses, 'finish_struct' has set
2014 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
2015 Similarly for a class whose base classes do not have vtables.
2016 When neither of these is true, we might have removed abstract
2017 virtuals (by providing a definition), added some (by declaring
2018 new ones), or redeclared ones from a base class. We need to
2019 recalculate what's really an abstract virtual at this point (by
2020 looking in the vtables). */
2021 get_pure_virtuals (t);
2023 /* If this type has a copy constructor or a destructor, force its
2024 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
2025 nonzero. This will cause it to be passed by invisible reference
2026 and prevent it from being returned in a register. */
2027 if (type_has_nontrivial_copy_init (t)
2028 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2031 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
2032 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
2034 SET_TYPE_MODE (variants, BLKmode);
2035 TREE_ADDRESSABLE (variants) = 1;
2040 /* Issue warnings about T having private constructors, but no friends,
2043 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
2044 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
2045 non-private static member functions. */
2048 maybe_warn_about_overly_private_class (tree t)
2050 int has_member_fn = 0;
2051 int has_nonprivate_method = 0;
2054 if (!warn_ctor_dtor_privacy
2055 /* If the class has friends, those entities might create and
2056 access instances, so we should not warn. */
2057 || (CLASSTYPE_FRIEND_CLASSES (t)
2058 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
2059 /* We will have warned when the template was declared; there's
2060 no need to warn on every instantiation. */
2061 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
2062 /* There's no reason to even consider warning about this
2066 /* We only issue one warning, if more than one applies, because
2067 otherwise, on code like:
2070 // Oops - forgot `public:'
2076 we warn several times about essentially the same problem. */
2078 /* Check to see if all (non-constructor, non-destructor) member
2079 functions are private. (Since there are no friends or
2080 non-private statics, we can't ever call any of the private member
2082 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
2083 /* We're not interested in compiler-generated methods; they don't
2084 provide any way to call private members. */
2085 if (!DECL_ARTIFICIAL (fn))
2087 if (!TREE_PRIVATE (fn))
2089 if (DECL_STATIC_FUNCTION_P (fn))
2090 /* A non-private static member function is just like a
2091 friend; it can create and invoke private member
2092 functions, and be accessed without a class
2096 has_nonprivate_method = 1;
2097 /* Keep searching for a static member function. */
2099 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
2103 if (!has_nonprivate_method && has_member_fn)
2105 /* There are no non-private methods, and there's at least one
2106 private member function that isn't a constructor or
2107 destructor. (If all the private members are
2108 constructors/destructors we want to use the code below that
2109 issues error messages specifically referring to
2110 constructors/destructors.) */
2112 tree binfo = TYPE_BINFO (t);
2114 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
2115 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
2117 has_nonprivate_method = 1;
2120 if (!has_nonprivate_method)
2122 warning (OPT_Wctor_dtor_privacy,
2123 "all member functions in class %qT are private", t);
2128 /* Even if some of the member functions are non-private, the class
2129 won't be useful for much if all the constructors or destructors
2130 are private: such an object can never be created or destroyed. */
2131 fn = CLASSTYPE_DESTRUCTORS (t);
2132 if (fn && TREE_PRIVATE (fn))
2134 warning (OPT_Wctor_dtor_privacy,
2135 "%q#T only defines a private destructor and has no friends",
2140 /* Warn about classes that have private constructors and no friends. */
2141 if (TYPE_HAS_USER_CONSTRUCTOR (t)
2142 /* Implicitly generated constructors are always public. */
2143 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
2144 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
2146 int nonprivate_ctor = 0;
2148 /* If a non-template class does not define a copy
2149 constructor, one is defined for it, enabling it to avoid
2150 this warning. For a template class, this does not
2151 happen, and so we would normally get a warning on:
2153 template <class T> class C { private: C(); };
2155 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
2156 complete non-template or fully instantiated classes have this
2158 if (!TYPE_HAS_COPY_CTOR (t))
2159 nonprivate_ctor = 1;
2161 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
2163 tree ctor = OVL_CURRENT (fn);
2164 /* Ideally, we wouldn't count copy constructors (or, in
2165 fact, any constructor that takes an argument of the
2166 class type as a parameter) because such things cannot
2167 be used to construct an instance of the class unless
2168 you already have one. But, for now at least, we're
2170 if (! TREE_PRIVATE (ctor))
2172 nonprivate_ctor = 1;
2177 if (nonprivate_ctor == 0)
2179 warning (OPT_Wctor_dtor_privacy,
2180 "%q#T only defines private constructors and has no friends",
2188 gt_pointer_operator new_value;
2192 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
2195 method_name_cmp (const void* m1_p, const void* m2_p)
2197 const tree *const m1 = (const tree *) m1_p;
2198 const tree *const m2 = (const tree *) m2_p;
2200 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
2202 if (*m1 == NULL_TREE)
2204 if (*m2 == NULL_TREE)
2206 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
2211 /* This routine compares two fields like method_name_cmp but using the
2212 pointer operator in resort_field_decl_data. */
2215 resort_method_name_cmp (const void* m1_p, const void* m2_p)
2217 const tree *const m1 = (const tree *) m1_p;
2218 const tree *const m2 = (const tree *) m2_p;
2219 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
2221 if (*m1 == NULL_TREE)
2223 if (*m2 == NULL_TREE)
2226 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
2227 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
2228 resort_data.new_value (&d1, resort_data.cookie);
2229 resort_data.new_value (&d2, resort_data.cookie);
2236 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
2239 resort_type_method_vec (void* obj,
2241 gt_pointer_operator new_value,
2244 vec<tree, va_gc> *method_vec = (vec<tree, va_gc> *) obj;
2245 int len = vec_safe_length (method_vec);
2249 /* The type conversion ops have to live at the front of the vec, so we
2251 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
2252 vec_safe_iterate (method_vec, slot, &fn);
2254 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
2259 resort_data.new_value = new_value;
2260 resort_data.cookie = cookie;
2261 qsort (method_vec->address () + slot, len - slot, sizeof (tree),
2262 resort_method_name_cmp);
2266 /* Warn about duplicate methods in fn_fields.
2268 Sort methods that are not special (i.e., constructors, destructors,
2269 and type conversion operators) so that we can find them faster in
2273 finish_struct_methods (tree t)
2276 vec<tree, va_gc> *method_vec;
2279 method_vec = CLASSTYPE_METHOD_VEC (t);
2283 len = method_vec->length ();
2285 /* Clear DECL_IN_AGGR_P for all functions. */
2286 for (fn_fields = TYPE_METHODS (t); fn_fields;
2287 fn_fields = DECL_CHAIN (fn_fields))
2288 DECL_IN_AGGR_P (fn_fields) = 0;
2290 /* Issue warnings about private constructors and such. If there are
2291 no methods, then some public defaults are generated. */
2292 maybe_warn_about_overly_private_class (t);
2294 /* The type conversion ops have to live at the front of the vec, so we
2296 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
2297 method_vec->iterate (slot, &fn_fields);
2299 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
2302 qsort (method_vec->address () + slot,
2303 len-slot, sizeof (tree), method_name_cmp);
2306 /* Make BINFO's vtable have N entries, including RTTI entries,
2307 vbase and vcall offsets, etc. Set its type and call the back end
2311 layout_vtable_decl (tree binfo, int n)
2316 atype = build_array_of_n_type (vtable_entry_type, n);
2317 layout_type (atype);
2319 /* We may have to grow the vtable. */
2320 vtable = get_vtbl_decl_for_binfo (binfo);
2321 if (!same_type_p (TREE_TYPE (vtable), atype))
2323 TREE_TYPE (vtable) = atype;
2324 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
2325 layout_decl (vtable, 0);
2329 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
2330 have the same signature. */
2333 same_signature_p (const_tree fndecl, const_tree base_fndecl)
2335 /* One destructor overrides another if they are the same kind of
2337 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
2338 && special_function_p (base_fndecl) == special_function_p (fndecl))
2340 /* But a non-destructor never overrides a destructor, nor vice
2341 versa, nor do different kinds of destructors override
2342 one-another. For example, a complete object destructor does not
2343 override a deleting destructor. */
2344 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
2347 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
2348 || (DECL_CONV_FN_P (fndecl)
2349 && DECL_CONV_FN_P (base_fndecl)
2350 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
2351 DECL_CONV_FN_TYPE (base_fndecl))))
2353 tree fntype = TREE_TYPE (fndecl);
2354 tree base_fntype = TREE_TYPE (base_fndecl);
2355 if (type_memfn_quals (fntype) == type_memfn_quals (base_fntype)
2356 && type_memfn_rqual (fntype) == type_memfn_rqual (base_fntype)
2357 && compparms (FUNCTION_FIRST_USER_PARMTYPE (fndecl),
2358 FUNCTION_FIRST_USER_PARMTYPE (base_fndecl)))
2364 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
2368 base_derived_from (tree derived, tree base)
2372 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
2374 if (probe == derived)
2376 else if (BINFO_VIRTUAL_P (probe))
2377 /* If we meet a virtual base, we can't follow the inheritance
2378 any more. See if the complete type of DERIVED contains
2379 such a virtual base. */
2380 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
2386 typedef struct find_final_overrider_data_s {
2387 /* The function for which we are trying to find a final overrider. */
2389 /* The base class in which the function was declared. */
2390 tree declaring_base;
2391 /* The candidate overriders. */
2393 /* Path to most derived. */
2395 } find_final_overrider_data;
2397 /* Add the overrider along the current path to FFOD->CANDIDATES.
2398 Returns true if an overrider was found; false otherwise. */
2401 dfs_find_final_overrider_1 (tree binfo,
2402 find_final_overrider_data *ffod,
2407 /* If BINFO is not the most derived type, try a more derived class.
2408 A definition there will overrider a definition here. */
2412 if (dfs_find_final_overrider_1
2413 (ffod->path[depth], ffod, depth))
2417 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
2420 tree *candidate = &ffod->candidates;
2422 /* Remove any candidates overridden by this new function. */
2425 /* If *CANDIDATE overrides METHOD, then METHOD
2426 cannot override anything else on the list. */
2427 if (base_derived_from (TREE_VALUE (*candidate), binfo))
2429 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
2430 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
2431 *candidate = TREE_CHAIN (*candidate);
2433 candidate = &TREE_CHAIN (*candidate);
2436 /* Add the new function. */
2437 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
2444 /* Called from find_final_overrider via dfs_walk. */
2447 dfs_find_final_overrider_pre (tree binfo, void *data)
2449 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
2451 if (binfo == ffod->declaring_base)
2452 dfs_find_final_overrider_1 (binfo, ffod, ffod->path.length ());
2453 ffod->path.safe_push (binfo);
2459 dfs_find_final_overrider_post (tree /*binfo*/, void *data)
2461 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
2467 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
2468 FN and whose TREE_VALUE is the binfo for the base where the
2469 overriding occurs. BINFO (in the hierarchy dominated by the binfo
2470 DERIVED) is the base object in which FN is declared. */
2473 find_final_overrider (tree derived, tree binfo, tree fn)
2475 find_final_overrider_data ffod;
2477 /* Getting this right is a little tricky. This is valid:
2479 struct S { virtual void f (); };
2480 struct T { virtual void f (); };
2481 struct U : public S, public T { };
2483 even though calling `f' in `U' is ambiguous. But,
2485 struct R { virtual void f(); };
2486 struct S : virtual public R { virtual void f (); };
2487 struct T : virtual public R { virtual void f (); };
2488 struct U : public S, public T { };
2490 is not -- there's no way to decide whether to put `S::f' or
2491 `T::f' in the vtable for `R'.
2493 The solution is to look at all paths to BINFO. If we find
2494 different overriders along any two, then there is a problem. */
2495 if (DECL_THUNK_P (fn))
2496 fn = THUNK_TARGET (fn);
2498 /* Determine the depth of the hierarchy. */
2500 ffod.declaring_base = binfo;
2501 ffod.candidates = NULL_TREE;
2502 ffod.path.create (30);
2504 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2505 dfs_find_final_overrider_post, &ffod);
2507 ffod.path.release ();
2509 /* If there was no winner, issue an error message. */
2510 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2511 return error_mark_node;
2513 return ffod.candidates;
2516 /* Return the index of the vcall offset for FN when TYPE is used as a
2520 get_vcall_index (tree fn, tree type)
2522 vec<tree_pair_s, va_gc> *indices = CLASSTYPE_VCALL_INDICES (type);
2526 FOR_EACH_VEC_SAFE_ELT (indices, ix, p)
2527 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2528 || same_signature_p (fn, p->purpose))
2531 /* There should always be an appropriate index. */
2535 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2536 dominated by T. FN is the old function; VIRTUALS points to the
2537 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2538 of that entry in the list. */
2541 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2549 tree overrider_fn, overrider_target;
2550 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2551 tree over_return, base_return;
2554 /* Find the nearest primary base (possibly binfo itself) which defines
2555 this function; this is the class the caller will convert to when
2556 calling FN through BINFO. */
2557 for (b = binfo; ; b = get_primary_binfo (b))
2560 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2563 /* The nearest definition is from a lost primary. */
2564 if (BINFO_LOST_PRIMARY_P (b))
2569 /* Find the final overrider. */
2570 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2571 if (overrider == error_mark_node)
2573 error ("no unique final overrider for %qD in %qT", target_fn, t);
2576 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2578 /* Check for adjusting covariant return types. */
2579 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2580 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2582 if (POINTER_TYPE_P (over_return)
2583 && TREE_CODE (over_return) == TREE_CODE (base_return)
2584 && CLASS_TYPE_P (TREE_TYPE (over_return))
2585 && CLASS_TYPE_P (TREE_TYPE (base_return))
2586 /* If the overrider is invalid, don't even try. */
2587 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2589 /* If FN is a covariant thunk, we must figure out the adjustment
2590 to the final base FN was converting to. As OVERRIDER_TARGET might
2591 also be converting to the return type of FN, we have to
2592 combine the two conversions here. */
2593 tree fixed_offset, virtual_offset;
2595 over_return = TREE_TYPE (over_return);
2596 base_return = TREE_TYPE (base_return);
2598 if (DECL_THUNK_P (fn))
2600 gcc_assert (DECL_RESULT_THUNK_P (fn));
2601 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2602 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2605 fixed_offset = virtual_offset = NULL_TREE;
2608 /* Find the equivalent binfo within the return type of the
2609 overriding function. We will want the vbase offset from
2611 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2613 else if (!same_type_ignoring_top_level_qualifiers_p
2614 (over_return, base_return))
2616 /* There was no existing virtual thunk (which takes
2617 precedence). So find the binfo of the base function's
2618 return type within the overriding function's return type.
2619 We cannot call lookup base here, because we're inside a
2620 dfs_walk, and will therefore clobber the BINFO_MARKED
2621 flags. Fortunately we know the covariancy is valid (it
2622 has already been checked), so we can just iterate along
2623 the binfos, which have been chained in inheritance graph
2624 order. Of course it is lame that we have to repeat the
2625 search here anyway -- we should really be caching pieces
2626 of the vtable and avoiding this repeated work. */
2627 tree thunk_binfo, base_binfo;
2629 /* Find the base binfo within the overriding function's
2630 return type. We will always find a thunk_binfo, except
2631 when the covariancy is invalid (which we will have
2632 already diagnosed). */
2633 for (base_binfo = TYPE_BINFO (base_return),
2634 thunk_binfo = TYPE_BINFO (over_return);
2636 thunk_binfo = TREE_CHAIN (thunk_binfo))
2637 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2638 BINFO_TYPE (base_binfo)))
2641 /* See if virtual inheritance is involved. */
2642 for (virtual_offset = thunk_binfo;
2644 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2645 if (BINFO_VIRTUAL_P (virtual_offset))
2649 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2651 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2655 /* We convert via virtual base. Adjust the fixed
2656 offset to be from there. */
2658 size_diffop (offset,
2660 BINFO_OFFSET (virtual_offset)));
2663 /* There was an existing fixed offset, this must be
2664 from the base just converted to, and the base the
2665 FN was thunking to. */
2666 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2668 fixed_offset = offset;
2672 if (fixed_offset || virtual_offset)
2673 /* Replace the overriding function with a covariant thunk. We
2674 will emit the overriding function in its own slot as
2676 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2677 fixed_offset, virtual_offset);
2680 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2681 !DECL_THUNK_P (fn));
2683 /* If we need a covariant thunk, then we may need to adjust first_defn.
2684 The ABI specifies that the thunks emitted with a function are
2685 determined by which bases the function overrides, so we need to be
2686 sure that we're using a thunk for some overridden base; even if we
2687 know that the necessary this adjustment is zero, there may not be an
2688 appropriate zero-this-adjusment thunk for us to use since thunks for
2689 overriding virtual bases always use the vcall offset.
2691 Furthermore, just choosing any base that overrides this function isn't
2692 quite right, as this slot won't be used for calls through a type that
2693 puts a covariant thunk here. Calling the function through such a type
2694 will use a different slot, and that slot is the one that determines
2695 the thunk emitted for that base.
2697 So, keep looking until we find the base that we're really overriding
2698 in this slot: the nearest primary base that doesn't use a covariant
2699 thunk in this slot. */
2700 if (overrider_target != overrider_fn)
2702 if (BINFO_TYPE (b) == DECL_CONTEXT (overrider_target))
2703 /* We already know that the overrider needs a covariant thunk. */
2704 b = get_primary_binfo (b);
2705 for (; ; b = get_primary_binfo (b))
2707 tree main_binfo = TYPE_BINFO (BINFO_TYPE (b));
2708 tree bv = chain_index (ix, BINFO_VIRTUALS (main_binfo));
2709 if (!DECL_THUNK_P (TREE_VALUE (bv)))
2711 if (BINFO_LOST_PRIMARY_P (b))
2717 /* Assume that we will produce a thunk that convert all the way to
2718 the final overrider, and not to an intermediate virtual base. */
2719 virtual_base = NULL_TREE;
2721 /* See if we can convert to an intermediate virtual base first, and then
2722 use the vcall offset located there to finish the conversion. */
2723 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2725 /* If we find the final overrider, then we can stop
2727 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2728 BINFO_TYPE (TREE_VALUE (overrider))))
2731 /* If we find a virtual base, and we haven't yet found the
2732 overrider, then there is a virtual base between the
2733 declaring base (first_defn) and the final overrider. */
2734 if (BINFO_VIRTUAL_P (b))
2741 /* Compute the constant adjustment to the `this' pointer. The
2742 `this' pointer, when this function is called, will point at BINFO
2743 (or one of its primary bases, which are at the same offset). */
2745 /* The `this' pointer needs to be adjusted from the declaration to
2746 the nearest virtual base. */
2747 delta = size_diffop_loc (input_location,
2748 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2749 convert (ssizetype, BINFO_OFFSET (first_defn)));
2751 /* If the nearest definition is in a lost primary, we don't need an
2752 entry in our vtable. Except possibly in a constructor vtable,
2753 if we happen to get our primary back. In that case, the offset
2754 will be zero, as it will be a primary base. */
2755 delta = size_zero_node;
2757 /* The `this' pointer needs to be adjusted from pointing to
2758 BINFO to pointing at the base where the final overrider
2760 delta = size_diffop_loc (input_location,
2762 BINFO_OFFSET (TREE_VALUE (overrider))),
2763 convert (ssizetype, BINFO_OFFSET (binfo)));
2765 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2768 BV_VCALL_INDEX (*virtuals)
2769 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2771 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2773 BV_LOST_PRIMARY (*virtuals) = lost;
2776 /* Called from modify_all_vtables via dfs_walk. */
2779 dfs_modify_vtables (tree binfo, void* data)
2781 tree t = (tree) data;
2786 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2787 /* A base without a vtable needs no modification, and its bases
2788 are uninteresting. */
2789 return dfs_skip_bases;
2791 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2792 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2793 /* Don't do the primary vtable, if it's new. */
2796 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2797 /* There's no need to modify the vtable for a non-virtual primary
2798 base; we're not going to use that vtable anyhow. We do still
2799 need to do this for virtual primary bases, as they could become
2800 non-primary in a construction vtable. */
2803 make_new_vtable (t, binfo);
2805 /* Now, go through each of the virtual functions in the virtual
2806 function table for BINFO. Find the final overrider, and update
2807 the BINFO_VIRTUALS list appropriately. */
2808 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2809 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2811 ix++, virtuals = TREE_CHAIN (virtuals),
2812 old_virtuals = TREE_CHAIN (old_virtuals))
2813 update_vtable_entry_for_fn (t,
2815 BV_FN (old_virtuals),
2821 /* Update all of the primary and secondary vtables for T. Create new
2822 vtables as required, and initialize their RTTI information. Each
2823 of the functions in VIRTUALS is declared in T and may override a
2824 virtual function from a base class; find and modify the appropriate
2825 entries to point to the overriding functions. Returns a list, in
2826 declaration order, of the virtual functions that are declared in T,
2827 but do not appear in the primary base class vtable, and which
2828 should therefore be appended to the end of the vtable for T. */
2831 modify_all_vtables (tree t, tree virtuals)
2833 tree binfo = TYPE_BINFO (t);
2836 /* Mangle the vtable name before entering dfs_walk (c++/51884). */
2837 if (TYPE_CONTAINS_VPTR_P (t))
2838 get_vtable_decl (t, false);
2840 /* Update all of the vtables. */
2841 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2843 /* Add virtual functions not already in our primary vtable. These
2844 will be both those introduced by this class, and those overridden
2845 from secondary bases. It does not include virtuals merely
2846 inherited from secondary bases. */
2847 for (fnsp = &virtuals; *fnsp; )
2849 tree fn = TREE_VALUE (*fnsp);
2851 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2852 || DECL_VINDEX (fn) == error_mark_node)
2854 /* We don't need to adjust the `this' pointer when
2855 calling this function. */
2856 BV_DELTA (*fnsp) = integer_zero_node;
2857 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2859 /* This is a function not already in our vtable. Keep it. */
2860 fnsp = &TREE_CHAIN (*fnsp);
2863 /* We've already got an entry for this function. Skip it. */
2864 *fnsp = TREE_CHAIN (*fnsp);
2870 /* Get the base virtual function declarations in T that have the
2874 get_basefndecls (tree name, tree t, vec<tree> *base_fndecls)
2877 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2880 /* Find virtual functions in T with the indicated NAME. */
2881 i = lookup_fnfields_1 (t, name);
2882 bool found_decls = false;
2884 for (methods = (*CLASSTYPE_METHOD_VEC (t))[i];
2886 methods = OVL_NEXT (methods))
2888 tree method = OVL_CURRENT (methods);
2890 if (TREE_CODE (method) == FUNCTION_DECL
2891 && DECL_VINDEX (method))
2893 base_fndecls->safe_push (method);
2901 for (i = 0; i < n_baseclasses; i++)
2903 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2904 get_basefndecls (name, basetype, base_fndecls);
2908 /* If this declaration supersedes the declaration of
2909 a method declared virtual in the base class, then
2910 mark this field as being virtual as well. */
2913 check_for_override (tree decl, tree ctype)
2915 bool overrides_found = false;
2916 if (TREE_CODE (decl) == TEMPLATE_DECL)
2917 /* In [temp.mem] we have:
2919 A specialization of a member function template does not
2920 override a virtual function from a base class. */
2922 if ((DECL_DESTRUCTOR_P (decl)
2923 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2924 || DECL_CONV_FN_P (decl))
2925 && look_for_overrides (ctype, decl)
2926 && !DECL_STATIC_FUNCTION_P (decl))
2927 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2928 the error_mark_node so that we know it is an overriding
2931 DECL_VINDEX (decl) = decl;
2932 overrides_found = true;
2933 if (warn_override && !DECL_OVERRIDE_P (decl)
2934 && !DECL_DESTRUCTOR_P (decl))
2935 warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wsuggest_override,
2936 "%q+D can be marked override", decl);
2939 if (DECL_VIRTUAL_P (decl))
2941 if (!DECL_VINDEX (decl))
2942 DECL_VINDEX (decl) = error_mark_node;
2943 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2944 if (DECL_DESTRUCTOR_P (decl))
2945 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (ctype) = true;
2947 else if (DECL_FINAL_P (decl))
2948 error ("%q+#D marked %<final%>, but is not virtual", decl);
2949 if (DECL_OVERRIDE_P (decl) && !overrides_found)
2950 error ("%q+#D marked %<override%>, but does not override", decl);
2953 /* Warn about hidden virtual functions that are not overridden in t.
2954 We know that constructors and destructors don't apply. */
2957 warn_hidden (tree t)
2959 vec<tree, va_gc> *method_vec = CLASSTYPE_METHOD_VEC (t);
2963 /* We go through each separately named virtual function. */
2964 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2965 vec_safe_iterate (method_vec, i, &fns);
2975 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2976 have the same name. Figure out what name that is. */
2977 name = DECL_NAME (OVL_CURRENT (fns));
2978 /* There are no possibly hidden functions yet. */
2979 auto_vec<tree, 20> base_fndecls;
2980 /* Iterate through all of the base classes looking for possibly
2981 hidden functions. */
2982 for (binfo = TYPE_BINFO (t), j = 0;
2983 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2985 tree basetype = BINFO_TYPE (base_binfo);
2986 get_basefndecls (name, basetype, &base_fndecls);
2989 /* If there are no functions to hide, continue. */
2990 if (base_fndecls.is_empty ())
2993 /* Remove any overridden functions. */
2994 for (fn = fns; fn; fn = OVL_NEXT (fn))
2996 fndecl = OVL_CURRENT (fn);
2997 if (TREE_CODE (fndecl) == FUNCTION_DECL
2998 && DECL_VINDEX (fndecl))
3000 /* If the method from the base class has the same
3001 signature as the method from the derived class, it
3002 has been overridden. */
3003 for (size_t k = 0; k < base_fndecls.length (); k++)
3005 && same_signature_p (fndecl, base_fndecls[k]))
3006 base_fndecls[k] = NULL_TREE;
3010 /* Now give a warning for all base functions without overriders,
3011 as they are hidden. */
3014 FOR_EACH_VEC_ELT (base_fndecls, k, base_fndecl)
3017 /* Here we know it is a hider, and no overrider exists. */
3018 warning (OPT_Woverloaded_virtual, "%q+D was hidden", base_fndecl);
3019 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
3024 /* Recursive helper for finish_struct_anon. */
3027 finish_struct_anon_r (tree field, bool complain)
3029 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
3030 tree elt = TYPE_FIELDS (TREE_TYPE (field));
3031 for (; elt; elt = DECL_CHAIN (elt))
3033 /* We're generally only interested in entities the user
3034 declared, but we also find nested classes by noticing
3035 the TYPE_DECL that we create implicitly. You're
3036 allowed to put one anonymous union inside another,
3037 though, so we explicitly tolerate that. We use
3038 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
3039 we also allow unnamed types used for defining fields. */
3040 if (DECL_ARTIFICIAL (elt)
3041 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
3042 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
3045 if (TREE_CODE (elt) != FIELD_DECL)
3047 /* We already complained about static data members in
3048 finish_static_data_member_decl. */
3049 if (complain && TREE_CODE (elt) != VAR_DECL)
3052 permerror (input_location,
3053 "%q+#D invalid; an anonymous union can "
3054 "only have non-static data members", elt);
3056 permerror (input_location,
3057 "%q+#D invalid; an anonymous struct can "
3058 "only have non-static data members", elt);
3065 if (TREE_PRIVATE (elt))
3068 permerror (input_location,
3069 "private member %q+#D in anonymous union", elt);
3071 permerror (input_location,
3072 "private member %q+#D in anonymous struct", elt);
3074 else if (TREE_PROTECTED (elt))
3077 permerror (input_location,
3078 "protected member %q+#D in anonymous union", elt);
3080 permerror (input_location,
3081 "protected member %q+#D in anonymous struct", elt);
3085 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
3086 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
3088 /* Recurse into the anonymous aggregates to handle correctly
3089 access control (c++/24926):
3100 if (DECL_NAME (elt) == NULL_TREE
3101 && ANON_AGGR_TYPE_P (TREE_TYPE (elt)))
3102 finish_struct_anon_r (elt, /*complain=*/false);
3106 /* Check for things that are invalid. There are probably plenty of other
3107 things we should check for also. */
3110 finish_struct_anon (tree t)
3112 for (tree field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
3114 if (TREE_STATIC (field))
3116 if (TREE_CODE (field) != FIELD_DECL)
3119 if (DECL_NAME (field) == NULL_TREE
3120 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
3121 finish_struct_anon_r (field, /*complain=*/true);
3125 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
3126 will be used later during class template instantiation.
3127 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
3128 a non-static member data (FIELD_DECL), a member function
3129 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
3130 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
3131 When FRIEND_P is nonzero, T is either a friend class
3132 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
3133 (FUNCTION_DECL, TEMPLATE_DECL). */
3136 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
3138 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
3139 if (CLASSTYPE_TEMPLATE_INFO (type))
3140 CLASSTYPE_DECL_LIST (type)
3141 = tree_cons (friend_p ? NULL_TREE : type,
3142 t, CLASSTYPE_DECL_LIST (type));
3145 /* This function is called from declare_virt_assop_and_dtor via
3148 DATA is a type that direcly or indirectly inherits the base
3149 represented by BINFO. If BINFO contains a virtual assignment [copy
3150 assignment or move assigment] operator or a virtual constructor,
3151 declare that function in DATA if it hasn't been already declared. */
3154 dfs_declare_virt_assop_and_dtor (tree binfo, void *data)
3156 tree bv, fn, t = (tree)data;
3157 tree opname = ansi_assopname (NOP_EXPR);
3159 gcc_assert (t && CLASS_TYPE_P (t));
3160 gcc_assert (binfo && TREE_CODE (binfo) == TREE_BINFO);
3162 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
3163 /* A base without a vtable needs no modification, and its bases
3164 are uninteresting. */
3165 return dfs_skip_bases;
3167 if (BINFO_PRIMARY_P (binfo))
3168 /* If this is a primary base, then we have already looked at the
3169 virtual functions of its vtable. */
3172 for (bv = BINFO_VIRTUALS (binfo); bv; bv = TREE_CHAIN (bv))
3176 if (DECL_NAME (fn) == opname)
3178 if (CLASSTYPE_LAZY_COPY_ASSIGN (t))
3179 lazily_declare_fn (sfk_copy_assignment, t);
3180 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
3181 lazily_declare_fn (sfk_move_assignment, t);
3183 else if (DECL_DESTRUCTOR_P (fn)
3184 && CLASSTYPE_LAZY_DESTRUCTOR (t))
3185 lazily_declare_fn (sfk_destructor, t);
3191 /* If the class type T has a direct or indirect base that contains a
3192 virtual assignment operator or a virtual destructor, declare that
3193 function in T if it hasn't been already declared. */
3196 declare_virt_assop_and_dtor (tree t)
3198 if (!(TYPE_POLYMORPHIC_P (t)
3199 && (CLASSTYPE_LAZY_COPY_ASSIGN (t)
3200 || CLASSTYPE_LAZY_MOVE_ASSIGN (t)
3201 || CLASSTYPE_LAZY_DESTRUCTOR (t))))
3204 dfs_walk_all (TYPE_BINFO (t),
3205 dfs_declare_virt_assop_and_dtor,
3209 /* Declare the inheriting constructor for class T inherited from base
3210 constructor CTOR with the parameter array PARMS of size NPARMS. */
3213 one_inheriting_sig (tree t, tree ctor, tree *parms, int nparms)
3215 /* We don't declare an inheriting ctor that would be a default,
3216 copy or move ctor for derived or base. */
3220 && TREE_CODE (parms[0]) == REFERENCE_TYPE)
3222 tree parm = TYPE_MAIN_VARIANT (TREE_TYPE (parms[0]));
3223 if (parm == t || parm == DECL_CONTEXT (ctor))
3227 tree parmlist = void_list_node;
3228 for (int i = nparms - 1; i >= 0; i--)
3229 parmlist = tree_cons (NULL_TREE, parms[i], parmlist);
3230 tree fn = implicitly_declare_fn (sfk_inheriting_constructor,
3231 t, false, ctor, parmlist);
3232 if (add_method (t, fn, NULL_TREE))
3234 DECL_CHAIN (fn) = TYPE_METHODS (t);
3235 TYPE_METHODS (t) = fn;
3239 /* Declare all the inheriting constructors for class T inherited from base
3240 constructor CTOR. */
3243 one_inherited_ctor (tree ctor, tree t)
3245 tree parms = FUNCTION_FIRST_USER_PARMTYPE (ctor);
3247 tree *new_parms = XALLOCAVEC (tree, list_length (parms));
3249 for (; parms && parms != void_list_node; parms = TREE_CHAIN (parms))
3251 if (TREE_PURPOSE (parms))
3252 one_inheriting_sig (t, ctor, new_parms, i);
3253 new_parms[i++] = TREE_VALUE (parms);
3255 one_inheriting_sig (t, ctor, new_parms, i);
3256 if (parms == NULL_TREE)
3258 if (warning (OPT_Winherited_variadic_ctor,
3259 "the ellipsis in %qD is not inherited", ctor))
3260 inform (DECL_SOURCE_LOCATION (ctor), "%qD declared here", ctor);
3264 /* Create default constructors, assignment operators, and so forth for
3265 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
3266 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
3267 the class cannot have a default constructor, copy constructor
3268 taking a const reference argument, or an assignment operator taking
3269 a const reference, respectively. */
3272 add_implicitly_declared_members (tree t, tree* access_decls,
3273 int cant_have_const_cctor,
3274 int cant_have_const_assignment)
3276 bool move_ok = false;
3278 if (cxx_dialect >= cxx11 && !CLASSTYPE_DESTRUCTORS (t)
3279 && !TYPE_HAS_COPY_CTOR (t) && !TYPE_HAS_COPY_ASSIGN (t)
3280 && !type_has_move_constructor (t) && !type_has_move_assign (t))
3284 if (!CLASSTYPE_DESTRUCTORS (t))
3286 /* In general, we create destructors lazily. */
3287 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
3289 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3290 && TYPE_FOR_JAVA (t))
3291 /* But if this is a Java class, any non-trivial destructor is
3292 invalid, even if compiler-generated. Therefore, if the
3293 destructor is non-trivial we create it now. */
3294 lazily_declare_fn (sfk_destructor, t);
3299 If there is no user-declared constructor for a class, a default
3300 constructor is implicitly declared. */
3301 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
3303 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
3304 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
3305 if (cxx_dialect >= cxx11)
3306 TYPE_HAS_CONSTEXPR_CTOR (t)
3307 /* This might force the declaration. */
3308 = type_has_constexpr_default_constructor (t);
3313 If a class definition does not explicitly declare a copy
3314 constructor, one is declared implicitly. */
3315 if (! TYPE_HAS_COPY_CTOR (t) && ! TYPE_FOR_JAVA (t))
3317 TYPE_HAS_COPY_CTOR (t) = 1;
3318 TYPE_HAS_CONST_COPY_CTOR (t) = !cant_have_const_cctor;
3319 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
3321 CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
3324 /* If there is no assignment operator, one will be created if and
3325 when it is needed. For now, just record whether or not the type
3326 of the parameter to the assignment operator will be a const or
3327 non-const reference. */
3328 if (!TYPE_HAS_COPY_ASSIGN (t) && !TYPE_FOR_JAVA (t))
3330 TYPE_HAS_COPY_ASSIGN (t) = 1;
3331 TYPE_HAS_CONST_COPY_ASSIGN (t) = !cant_have_const_assignment;
3332 CLASSTYPE_LAZY_COPY_ASSIGN (t) = 1;
3333 if (move_ok && !LAMBDA_TYPE_P (t))
3334 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 1;
3337 /* We can't be lazy about declaring functions that might override
3338 a virtual function from a base class. */
3339 declare_virt_assop_and_dtor (t);
3341 while (*access_decls)
3343 tree using_decl = TREE_VALUE (*access_decls);
3344 tree decl = USING_DECL_DECLS (using_decl);
3345 if (DECL_NAME (using_decl) == ctor_identifier)
3347 /* declare, then remove the decl */
3348 tree ctor_list = decl;
3349 location_t loc = input_location;
3350 input_location = DECL_SOURCE_LOCATION (using_decl);
3352 for (; ctor_list; ctor_list = OVL_NEXT (ctor_list))
3353 one_inherited_ctor (OVL_CURRENT (ctor_list), t);
3354 *access_decls = TREE_CHAIN (*access_decls);
3355 input_location = loc;
3358 access_decls = &TREE_CHAIN (*access_decls);
3362 /* Subroutine of insert_into_classtype_sorted_fields. Recursively
3363 count the number of fields in TYPE, including anonymous union
3367 count_fields (tree fields)
3371 for (x = fields; x; x = DECL_CHAIN (x))
3373 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
3374 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
3381 /* Subroutine of insert_into_classtype_sorted_fields. Recursively add
3382 all the fields in the TREE_LIST FIELDS to the SORTED_FIELDS_TYPE
3383 elts, starting at offset IDX. */
3386 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
3389 for (x = fields; x; x = DECL_CHAIN (x))
3391 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
3392 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
3394 field_vec->elts[idx++] = x;
3399 /* Add all of the enum values of ENUMTYPE, to the FIELD_VEC elts,
3400 starting at offset IDX. */
3403 add_enum_fields_to_record_type (tree enumtype,
3404 struct sorted_fields_type *field_vec,
3408 for (values = TYPE_VALUES (enumtype); values; values = TREE_CHAIN (values))
3409 field_vec->elts[idx++] = TREE_VALUE (values);
3413 /* FIELD is a bit-field. We are finishing the processing for its
3414 enclosing type. Issue any appropriate messages and set appropriate
3415 flags. Returns false if an error has been diagnosed. */
3418 check_bitfield_decl (tree field)
3420 tree type = TREE_TYPE (field);
3423 /* Extract the declared width of the bitfield, which has been
3424 temporarily stashed in DECL_INITIAL. */
3425 w = DECL_INITIAL (field);
3426 gcc_assert (w != NULL_TREE);
3427 /* Remove the bit-field width indicator so that the rest of the
3428 compiler does not treat that value as an initializer. */
3429 DECL_INITIAL (field) = NULL_TREE;
3431 /* Detect invalid bit-field type. */
3432 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
3434 error ("bit-field %q+#D with non-integral type", field);
3435 w = error_mark_node;
3439 location_t loc = input_location;
3440 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
3443 /* detect invalid field size. */
3444 input_location = DECL_SOURCE_LOCATION (field);
3445 w = cxx_constant_value (w);
3446 input_location = loc;
3448 if (TREE_CODE (w) != INTEGER_CST)
3450 error ("bit-field %q+D width not an integer constant", field);
3451 w = error_mark_node;
3453 else if (tree_int_cst_sgn (w) < 0)
3455 error ("negative width in bit-field %q+D", field);
3456 w = error_mark_node;
3458 else if (integer_zerop (w) && DECL_NAME (field) != 0)
3460 error ("zero width for bit-field %q+D", field);
3461 w = error_mark_node;
3463 else if ((TREE_CODE (type) != ENUMERAL_TYPE
3464 && TREE_CODE (type) != BOOLEAN_TYPE
3465 && compare_tree_int (w, TYPE_PRECISION (type)) > 0)
3466 || ((TREE_CODE (type) == ENUMERAL_TYPE
3467 || TREE_CODE (type) == BOOLEAN_TYPE)
3468 && tree_int_cst_lt (TYPE_SIZE (type), w)))
3469 warning (0, "width of %q+D exceeds its type", field);
3470 else if (TREE_CODE (type) == ENUMERAL_TYPE
3471 && (0 > (compare_tree_int
3472 (w, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type))))))
3473 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
3476 if (w != error_mark_node)
3478 DECL_SIZE (field) = convert (bitsizetype, w);
3479 DECL_BIT_FIELD (field) = 1;
3484 /* Non-bit-fields are aligned for their type. */
3485 DECL_BIT_FIELD (field) = 0;
3486 CLEAR_DECL_C_BIT_FIELD (field);
3491 /* FIELD is a non bit-field. We are finishing the processing for its
3492 enclosing type T. Issue any appropriate messages and set appropriate
3496 check_field_decl (tree field,
3498 int* cant_have_const_ctor,
3499 int* no_const_asn_ref,
3500 int* any_default_members)
3502 tree type = strip_array_types (TREE_TYPE (field));
3504 /* In C++98 an anonymous union cannot contain any fields which would change
3505 the settings of CANT_HAVE_CONST_CTOR and friends. */
3506 if (ANON_UNION_TYPE_P (type) && cxx_dialect < cxx11)
3508 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
3509 structs. So, we recurse through their fields here. */
3510 else if (ANON_AGGR_TYPE_P (type))
3514 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
3515 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
3516 check_field_decl (fields, t, cant_have_const_ctor,
3517 no_const_asn_ref, any_default_members);
3519 /* Check members with class type for constructors, destructors,
3521 else if (CLASS_TYPE_P (type))
3523 /* Never let anything with uninheritable virtuals
3524 make it through without complaint. */
3525 abstract_virtuals_error (field, type);
3527 if (TREE_CODE (t) == UNION_TYPE && cxx_dialect < cxx11)
3530 int oldcount = errorcount;
3531 if (TYPE_NEEDS_CONSTRUCTING (type))
3532 error ("member %q+#D with constructor not allowed in union",
3534 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
3535 error ("member %q+#D with destructor not allowed in union", field);
3536 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
3537 error ("member %q+#D with copy assignment operator not allowed in union",
3539 if (!warned && errorcount > oldcount)
3541 inform (DECL_SOURCE_LOCATION (field), "unrestricted unions "
3542 "only available with -std=c++11 or -std=gnu++11");
3548 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
3549 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3550 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
3551 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
3552 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type)
3553 || !TYPE_HAS_COPY_ASSIGN (type));
3554 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type)
3555 || !TYPE_HAS_COPY_CTOR (type));
3556 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type);
3557 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type);
3558 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type)
3559 || TYPE_HAS_COMPLEX_DFLT (type));
3562 if (TYPE_HAS_COPY_CTOR (type)
3563 && !TYPE_HAS_CONST_COPY_CTOR (type))
3564 *cant_have_const_ctor = 1;
3566 if (TYPE_HAS_COPY_ASSIGN (type)
3567 && !TYPE_HAS_CONST_COPY_ASSIGN (type))
3568 *no_const_asn_ref = 1;
3571 check_abi_tags (t, field);
3573 if (DECL_INITIAL (field) != NULL_TREE)
3575 /* `build_class_init_list' does not recognize
3577 if (TREE_CODE (t) == UNION_TYPE && *any_default_members != 0)
3578 error ("multiple fields in union %qT initialized", t);
3579 *any_default_members = 1;
3583 /* Check the data members (both static and non-static), class-scoped
3584 typedefs, etc., appearing in the declaration of T. Issue
3585 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
3586 declaration order) of access declarations; each TREE_VALUE in this
3587 list is a USING_DECL.
3589 In addition, set the following flags:
3592 The class is empty, i.e., contains no non-static data members.
3594 CANT_HAVE_CONST_CTOR_P
3595 This class cannot have an implicitly generated copy constructor
3596 taking a const reference.
3598 CANT_HAVE_CONST_ASN_REF
3599 This class cannot have an implicitly generated assignment
3600 operator taking a const reference.
3602 All of these flags should be initialized before calling this
3605 Returns a pointer to the end of the TYPE_FIELDs chain; additional
3606 fields can be added by adding to this chain. */
3609 check_field_decls (tree t, tree *access_decls,
3610 int *cant_have_const_ctor_p,
3611 int *no_const_asn_ref_p)
3616 int any_default_members;
3618 int field_access = -1;
3620 /* Assume there are no access declarations. */
3621 *access_decls = NULL_TREE;
3622 /* Assume this class has no pointer members. */
3623 has_pointers = false;
3624 /* Assume none of the members of this class have default
3626 any_default_members = 0;
3628 for (field = &TYPE_FIELDS (t); *field; field = next)
3631 tree type = TREE_TYPE (x);
3632 int this_field_access;
3634 next = &DECL_CHAIN (x);
3636 if (TREE_CODE (x) == USING_DECL)
3638 /* Save the access declarations for our caller. */
3639 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
3643 if (TREE_CODE (x) == TYPE_DECL
3644 || TREE_CODE (x) == TEMPLATE_DECL)
3647 /* If we've gotten this far, it's a data member, possibly static,
3648 or an enumerator. */
3649 if (TREE_CODE (x) != CONST_DECL)
3650 DECL_CONTEXT (x) = t;
3652 /* When this goes into scope, it will be a non-local reference. */
3653 DECL_NONLOCAL (x) = 1;
3655 if (TREE_CODE (t) == UNION_TYPE
3656 && cxx_dialect < cxx11)
3658 /* [class.union] (C++98)
3660 If a union contains a static data member, or a member of
3661 reference type, the program is ill-formed.
3663 In C++11 this limitation doesn't exist anymore. */
3666 error ("in C++98 %q+D may not be static because it is "
3667 "a member of a union", x);
3670 if (TREE_CODE (type) == REFERENCE_TYPE)
3672 error ("in C++98 %q+D may not have reference type %qT "
3673 "because it is a member of a union", x, type);
3678 /* Perform error checking that did not get done in
3680 if (TREE_CODE (type) == FUNCTION_TYPE)
3682 error ("field %q+D invalidly declared function type", x);
3683 type = build_pointer_type (type);
3684 TREE_TYPE (x) = type;
3686 else if (TREE_CODE (type) == METHOD_TYPE)
3688 error ("field %q+D invalidly declared method type", x);
3689 type = build_pointer_type (type);
3690 TREE_TYPE (x) = type;
3693 if (type == error_mark_node)
3696 if (TREE_CODE (x) == CONST_DECL || VAR_P (x))
3699 /* Now it can only be a FIELD_DECL. */
3701 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3702 CLASSTYPE_NON_AGGREGATE (t) = 1;
3704 /* If at least one non-static data member is non-literal, the whole
3705 class becomes non-literal. Per Core/1453, volatile non-static
3706 data members and base classes are also not allowed.
3707 Note: if the type is incomplete we will complain later on. */
3708 if (COMPLETE_TYPE_P (type)
3709 && (!literal_type_p (type) || CP_TYPE_VOLATILE_P (type)))
3710 CLASSTYPE_LITERAL_P (t) = false;
3712 /* A standard-layout class is a class that:
3714 has the same access control (Clause 11) for all non-static data members,
3716 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3717 if (field_access == -1)
3718 field_access = this_field_access;
3719 else if (this_field_access != field_access)
3720 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3722 /* If this is of reference type, check if it needs an init. */
3723 if (TREE_CODE (type) == REFERENCE_TYPE)
3725 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3726 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3727 if (DECL_INITIAL (x) == NULL_TREE)
3728 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3729 if (cxx_dialect < cxx11)
3731 /* ARM $12.6.2: [A member initializer list] (or, for an
3732 aggregate, initialization by a brace-enclosed list) is the
3733 only way to initialize nonstatic const and reference
3735 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3736 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3740 type = strip_array_types (type);
3742 if (TYPE_PACKED (t))
3744 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3748 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3752 else if (DECL_C_BIT_FIELD (x)
3753 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3754 DECL_PACKED (x) = 1;
3757 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3758 /* We don't treat zero-width bitfields as making a class
3763 /* The class is non-empty. */
3764 CLASSTYPE_EMPTY_P (t) = 0;
3765 /* The class is not even nearly empty. */
3766 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3767 /* If one of the data members contains an empty class,
3769 if (CLASS_TYPE_P (type)
3770 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3771 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3774 /* This is used by -Weffc++ (see below). Warn only for pointers
3775 to members which might hold dynamic memory. So do not warn
3776 for pointers to functions or pointers to members. */
3777 if (TYPE_PTR_P (type)
3778 && !TYPE_PTRFN_P (type))
3779 has_pointers = true;
3781 if (CLASS_TYPE_P (type))
3783 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3784 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3785 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3786 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3789 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3790 CLASSTYPE_HAS_MUTABLE (t) = 1;
3792 if (DECL_MUTABLE_P (x))
3794 if (CP_TYPE_CONST_P (type))
3796 error ("member %q+D cannot be declared both %<const%> "
3797 "and %<mutable%>", x);
3800 if (TREE_CODE (type) == REFERENCE_TYPE)
3802 error ("member %q+D cannot be declared as a %<mutable%> "
3808 if (! layout_pod_type_p (type))
3809 /* DR 148 now allows pointers to members (which are POD themselves),
3810 to be allowed in POD structs. */
3811 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3813 if (!std_layout_type_p (type))
3814 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3816 if (! zero_init_p (type))
3817 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3819 /* We set DECL_C_BIT_FIELD in grokbitfield.
3820 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3821 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3822 check_field_decl (x, t,
3823 cant_have_const_ctor_p,
3825 &any_default_members);
3827 /* Now that we've removed bit-field widths from DECL_INITIAL,
3828 anything left in DECL_INITIAL is an NSDMI that makes the class
3829 non-aggregate in C++11. */
3830 if (DECL_INITIAL (x) && cxx_dialect < cxx14)
3831 CLASSTYPE_NON_AGGREGATE (t) = true;
3833 /* If any field is const, the structure type is pseudo-const. */
3834 if (CP_TYPE_CONST_P (type))
3836 C_TYPE_FIELDS_READONLY (t) = 1;
3837 if (DECL_INITIAL (x) == NULL_TREE)
3838 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3839 if (cxx_dialect < cxx11)
3841 /* ARM $12.6.2: [A member initializer list] (or, for an
3842 aggregate, initialization by a brace-enclosed list) is the
3843 only way to initialize nonstatic const and reference
3845 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3846 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3849 /* A field that is pseudo-const makes the structure likewise. */
3850 else if (CLASS_TYPE_P (type))
3852 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3853 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3854 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3855 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3858 /* Core issue 80: A nonstatic data member is required to have a
3859 different name from the class iff the class has a
3860 user-declared constructor. */
3861 if (constructor_name_p (DECL_NAME (x), t)
3862 && TYPE_HAS_USER_CONSTRUCTOR (t))
3863 permerror (input_location, "field %q+#D with same name as class", x);
3866 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3867 it should also define a copy constructor and an assignment operator to
3868 implement the correct copy semantic (deep vs shallow, etc.). As it is
3869 not feasible to check whether the constructors do allocate dynamic memory
3870 and store it within members, we approximate the warning like this:
3872 -- Warn only if there are members which are pointers
3873 -- Warn only if there is a non-trivial constructor (otherwise,
3874 there cannot be memory allocated).
3875 -- Warn only if there is a non-trivial destructor. We assume that the
3876 user at least implemented the cleanup correctly, and a destructor
3877 is needed to free dynamic memory.
3879 This seems enough for practical purposes. */
3882 && TYPE_HAS_USER_CONSTRUCTOR (t)
3883 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3884 && !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
3886 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3888 if (! TYPE_HAS_COPY_CTOR (t))
3890 warning (OPT_Weffc__,
3891 " but does not override %<%T(const %T&)%>", t, t);
3892 if (!TYPE_HAS_COPY_ASSIGN (t))
3893 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3895 else if (! TYPE_HAS_COPY_ASSIGN (t))
3896 warning (OPT_Weffc__,
3897 " but does not override %<operator=(const %T&)%>", t);
3900 /* Non-static data member initializers make the default constructor
3902 if (any_default_members)
3904 TYPE_NEEDS_CONSTRUCTING (t) = true;
3905 TYPE_HAS_COMPLEX_DFLT (t) = true;
3908 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3910 TYPE_PACKED (t) = 0;
3912 /* Check anonymous struct/anonymous union fields. */
3913 finish_struct_anon (t);
3915 /* We've built up the list of access declarations in reverse order.
3917 *access_decls = nreverse (*access_decls);
3920 /* If TYPE is an empty class type, records its OFFSET in the table of
3924 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3928 if (!is_empty_class (type))
3931 /* Record the location of this empty object in OFFSETS. */
3932 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3934 n = splay_tree_insert (offsets,
3935 (splay_tree_key) offset,
3936 (splay_tree_value) NULL_TREE);
3937 n->value = ((splay_tree_value)
3938 tree_cons (NULL_TREE,
3945 /* Returns nonzero if TYPE is an empty class type and there is
3946 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3949 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3954 if (!is_empty_class (type))
3957 /* Record the location of this empty object in OFFSETS. */
3958 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3962 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3963 if (same_type_p (TREE_VALUE (t), type))
3969 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3970 F for every subobject, passing it the type, offset, and table of
3971 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3974 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3975 than MAX_OFFSET will not be walked.
3977 If F returns a nonzero value, the traversal ceases, and that value
3978 is returned. Otherwise, returns zero. */
3981 walk_subobject_offsets (tree type,
3982 subobject_offset_fn f,
3989 tree type_binfo = NULL_TREE;
3991 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3993 if (max_offset && tree_int_cst_lt (max_offset, offset))
3996 if (type == error_mark_node)
4002 type = BINFO_TYPE (type);
4005 if (CLASS_TYPE_P (type))
4011 /* Avoid recursing into objects that are not interesting. */
4012 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
4015 /* Record the location of TYPE. */
4016 r = (*f) (type, offset, offsets);
4020 /* Iterate through the direct base classes of TYPE. */
4022 type_binfo = TYPE_BINFO (type);
4023 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
4027 if (BINFO_VIRTUAL_P (binfo))
4031 /* We cannot rely on BINFO_OFFSET being set for the base
4032 class yet, but the offsets for direct non-virtual
4033 bases can be calculated by going back to the TYPE. */
4034 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
4035 binfo_offset = size_binop (PLUS_EXPR,
4037 BINFO_OFFSET (orig_binfo));
4039 r = walk_subobject_offsets (binfo,
4049 if (CLASSTYPE_VBASECLASSES (type))
4052 vec<tree, va_gc> *vbases;
4054 /* Iterate through the virtual base classes of TYPE. In G++
4055 3.2, we included virtual bases in the direct base class
4056 loop above, which results in incorrect results; the
4057 correct offsets for virtual bases are only known when
4058 working with the most derived type. */
4060 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
4061 vec_safe_iterate (vbases, ix, &binfo); ix++)
4063 r = walk_subobject_offsets (binfo,
4065 size_binop (PLUS_EXPR,
4067 BINFO_OFFSET (binfo)),
4076 /* We still have to walk the primary base, if it is
4077 virtual. (If it is non-virtual, then it was walked
4079 tree vbase = get_primary_binfo (type_binfo);
4081 if (vbase && BINFO_VIRTUAL_P (vbase)
4082 && BINFO_PRIMARY_P (vbase)
4083 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
4085 r = (walk_subobject_offsets
4087 offsets, max_offset, /*vbases_p=*/0));
4094 /* Iterate through the fields of TYPE. */
4095 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
4096 if (TREE_CODE (field) == FIELD_DECL
4097 && TREE_TYPE (field) != error_mark_node
4098 && !DECL_ARTIFICIAL (field))
4102 field_offset = byte_position (field);
4104 r = walk_subobject_offsets (TREE_TYPE (field),
4106 size_binop (PLUS_EXPR,
4116 else if (TREE_CODE (type) == ARRAY_TYPE)
4118 tree element_type = strip_array_types (type);
4119 tree domain = TYPE_DOMAIN (type);
4122 /* Avoid recursing into objects that are not interesting. */
4123 if (!CLASS_TYPE_P (element_type)
4124 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
4127 /* Step through each of the elements in the array. */
4128 for (index = size_zero_node;
4129 !tree_int_cst_lt (TYPE_MAX_VALUE (domain), index);
4130 index = size_binop (PLUS_EXPR, index, size_one_node))
4132 r = walk_subobject_offsets (TREE_TYPE (type),
4140 offset = size_binop (PLUS_EXPR, offset,
4141 TYPE_SIZE_UNIT (TREE_TYPE (type)));
4142 /* If this new OFFSET is bigger than the MAX_OFFSET, then
4143 there's no point in iterating through the remaining
4144 elements of the array. */
4145 if (max_offset && tree_int_cst_lt (max_offset, offset))
4153 /* Record all of the empty subobjects of TYPE (either a type or a
4154 binfo). If IS_DATA_MEMBER is true, then a non-static data member
4155 is being placed at OFFSET; otherwise, it is a base class that is
4156 being placed at OFFSET. */
4159 record_subobject_offsets (tree type,
4162 bool is_data_member)
4165 /* If recording subobjects for a non-static data member or a
4166 non-empty base class , we do not need to record offsets beyond
4167 the size of the biggest empty class. Additional data members
4168 will go at the end of the class. Additional base classes will go
4169 either at offset zero (if empty, in which case they cannot
4170 overlap with offsets past the size of the biggest empty class) or
4171 at the end of the class.
4173 However, if we are placing an empty base class, then we must record
4174 all offsets, as either the empty class is at offset zero (where
4175 other empty classes might later be placed) or at the end of the
4176 class (where other objects might then be placed, so other empty
4177 subobjects might later overlap). */
4179 || !is_empty_class (BINFO_TYPE (type)))
4180 max_offset = sizeof_biggest_empty_class;
4182 max_offset = NULL_TREE;
4183 walk_subobject_offsets (type, record_subobject_offset, offset,
4184 offsets, max_offset, is_data_member);
4187 /* Returns nonzero if any of the empty subobjects of TYPE (located at
4188 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
4189 virtual bases of TYPE are examined. */
4192 layout_conflict_p (tree type,
4197 splay_tree_node max_node;
4199 /* Get the node in OFFSETS that indicates the maximum offset where
4200 an empty subobject is located. */
4201 max_node = splay_tree_max (offsets);
4202 /* If there aren't any empty subobjects, then there's no point in
4203 performing this check. */
4207 return walk_subobject_offsets (type, check_subobject_offset, offset,
4208 offsets, (tree) (max_node->key),
4212 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
4213 non-static data member of the type indicated by RLI. BINFO is the
4214 binfo corresponding to the base subobject, OFFSETS maps offsets to
4215 types already located at those offsets. This function determines
4216 the position of the DECL. */
4219 layout_nonempty_base_or_field (record_layout_info rli,
4224 tree offset = NULL_TREE;
4230 /* For the purposes of determining layout conflicts, we want to
4231 use the class type of BINFO; TREE_TYPE (DECL) will be the
4232 CLASSTYPE_AS_BASE version, which does not contain entries for
4233 zero-sized bases. */
4234 type = TREE_TYPE (binfo);
4239 type = TREE_TYPE (decl);
4243 /* Try to place the field. It may take more than one try if we have
4244 a hard time placing the field without putting two objects of the
4245 same type at the same address. */
4248 struct record_layout_info_s old_rli = *rli;
4250 /* Place this field. */
4251 place_field (rli, decl);
4252 offset = byte_position (decl);
4254 /* We have to check to see whether or not there is already
4255 something of the same type at the offset we're about to use.
4256 For example, consider:
4259 struct T : public S { int i; };
4260 struct U : public S, public T {};
4262 Here, we put S at offset zero in U. Then, we can't put T at
4263 offset zero -- its S component would be at the same address
4264 as the S we already allocated. So, we have to skip ahead.
4265 Since all data members, including those whose type is an
4266 empty class, have nonzero size, any overlap can happen only
4267 with a direct or indirect base-class -- it can't happen with
4269 /* In a union, overlap is permitted; all members are placed at
4271 if (TREE_CODE (rli->t) == UNION_TYPE)
4273 if (layout_conflict_p (field_p ? type : binfo, offset,
4276 /* Strip off the size allocated to this field. That puts us
4277 at the first place we could have put the field with
4278 proper alignment. */
4281 /* Bump up by the alignment required for the type. */
4283 = size_binop (PLUS_EXPR, rli->bitpos,
4285 ? CLASSTYPE_ALIGN (type)
4286 : TYPE_ALIGN (type)));
4287 normalize_rli (rli);
4289 else if (TREE_CODE (type) == NULLPTR_TYPE
4290 && warn_abi && abi_version_crosses (9))
4292 /* Before ABI v9, we were giving nullptr_t alignment of 1; if
4293 the offset wasn't aligned like a pointer when we started to
4294 layout this field, that affects its position. */
4295 tree pos = rli_size_unit_so_far (&old_rli);
4296 if (int_cst_value (pos) % TYPE_ALIGN_UNIT (ptr_type_node) != 0)
4298 if (abi_version_at_least (9))
4299 warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wabi,
4300 "alignment of %qD increased in -fabi-version=9 "
4303 warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wabi, "alignment "
4304 "of %qD will increase in -fabi-version=9", decl);
4309 /* There was no conflict. We're done laying out this field. */
4313 /* Now that we know where it will be placed, update its
4315 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
4316 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
4317 this point because their BINFO_OFFSET is copied from another
4318 hierarchy. Therefore, we may not need to add the entire
4320 propagate_binfo_offsets (binfo,
4321 size_diffop_loc (input_location,
4322 convert (ssizetype, offset),
4324 BINFO_OFFSET (binfo))));
4327 /* Returns true if TYPE is empty and OFFSET is nonzero. */
4330 empty_base_at_nonzero_offset_p (tree type,
4332 splay_tree /*offsets*/)
4334 return is_empty_class (type) && !integer_zerop (offset);
4337 /* Layout the empty base BINFO. EOC indicates the byte currently just
4338 past the end of the class, and should be correctly aligned for a
4339 class of the type indicated by BINFO; OFFSETS gives the offsets of
4340 the empty bases allocated so far. T is the most derived
4341 type. Return nonzero iff we added it at the end. */
4344 layout_empty_base (record_layout_info rli, tree binfo,
4345 tree eoc, splay_tree offsets)
4348 tree basetype = BINFO_TYPE (binfo);
4351 /* This routine should only be used for empty classes. */
4352 gcc_assert (is_empty_class (basetype));
4353 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
4355 if (!integer_zerop (BINFO_OFFSET (binfo)))
4356 propagate_binfo_offsets
4357 (binfo, size_diffop_loc (input_location,
4358 size_zero_node, BINFO_OFFSET (binfo)));
4360 /* This is an empty base class. We first try to put it at offset
4362 if (layout_conflict_p (binfo,
4363 BINFO_OFFSET (binfo),
4367 /* That didn't work. Now, we move forward from the next
4368 available spot in the class. */
4370 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
4373 if (!layout_conflict_p (binfo,
4374 BINFO_OFFSET (binfo),
4377 /* We finally found a spot where there's no overlap. */
4380 /* There's overlap here, too. Bump along to the next spot. */
4381 propagate_binfo_offsets (binfo, alignment);
4385 if (CLASSTYPE_USER_ALIGN (basetype))
4387 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
4389 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
4390 TYPE_USER_ALIGN (rli->t) = 1;
4396 /* Layout the base given by BINFO in the class indicated by RLI.
4397 *BASE_ALIGN is a running maximum of the alignments of
4398 any base class. OFFSETS gives the location of empty base
4399 subobjects. T is the most derived type. Return nonzero if the new
4400 object cannot be nearly-empty. A new FIELD_DECL is inserted at
4401 *NEXT_FIELD, unless BINFO is for an empty base class.
4403 Returns the location at which the next field should be inserted. */
4406 build_base_field (record_layout_info rli, tree binfo,
4407 splay_tree offsets, tree *next_field)
4410 tree basetype = BINFO_TYPE (binfo);
4412 if (!COMPLETE_TYPE_P (basetype))
4413 /* This error is now reported in xref_tag, thus giving better
4414 location information. */
4417 /* Place the base class. */
4418 if (!is_empty_class (basetype))
4422 /* The containing class is non-empty because it has a non-empty
4424 CLASSTYPE_EMPTY_P (t) = 0;
4426 /* Create the FIELD_DECL. */
4427 decl = build_decl (input_location,
4428 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
4429 DECL_ARTIFICIAL (decl) = 1;
4430 DECL_IGNORED_P (decl) = 1;
4431 DECL_FIELD_CONTEXT (decl) = t;
4432 if (CLASSTYPE_AS_BASE (basetype))
4434 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
4435 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
4436 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
4437 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
4438 DECL_MODE (decl) = TYPE_MODE (basetype);
4439 DECL_FIELD_IS_BASE (decl) = 1;
4441 /* Try to place the field. It may take more than one try if we
4442 have a hard time placing the field without putting two
4443 objects of the same type at the same address. */
4444 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
4445 /* Add the new FIELD_DECL to the list of fields for T. */
4446 DECL_CHAIN (decl) = *next_field;
4448 next_field = &DECL_CHAIN (decl);
4456 /* On some platforms (ARM), even empty classes will not be
4458 eoc = round_up_loc (input_location,
4459 rli_size_unit_so_far (rli),
4460 CLASSTYPE_ALIGN_UNIT (basetype));
4461 atend = layout_empty_base (rli, binfo, eoc, offsets);
4462 /* A nearly-empty class "has no proper base class that is empty,
4463 not morally virtual, and at an offset other than zero." */
4464 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
4467 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4468 /* The check above (used in G++ 3.2) is insufficient because
4469 an empty class placed at offset zero might itself have an
4470 empty base at a nonzero offset. */
4471 else if (walk_subobject_offsets (basetype,
4472 empty_base_at_nonzero_offset_p,
4475 /*max_offset=*/NULL_TREE,
4477 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4480 /* We do not create a FIELD_DECL for empty base classes because
4481 it might overlap some other field. We want to be able to
4482 create CONSTRUCTORs for the class by iterating over the
4483 FIELD_DECLs, and the back end does not handle overlapping
4486 /* An empty virtual base causes a class to be non-empty
4487 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
4488 here because that was already done when the virtual table
4489 pointer was created. */
4492 /* Record the offsets of BINFO and its base subobjects. */
4493 record_subobject_offsets (binfo,
4494 BINFO_OFFSET (binfo),
4496 /*is_data_member=*/false);
4501 /* Layout all of the non-virtual base classes. Record empty
4502 subobjects in OFFSETS. T is the most derived type. Return nonzero
4503 if the type cannot be nearly empty. The fields created
4504 corresponding to the base classes will be inserted at
4508 build_base_fields (record_layout_info rli,
4509 splay_tree offsets, tree *next_field)
4511 /* Chain to hold all the new FIELD_DECLs which stand in for base class
4514 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
4517 /* The primary base class is always allocated first. */
4518 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
4519 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
4520 offsets, next_field);
4522 /* Now allocate the rest of the bases. */
4523 for (i = 0; i < n_baseclasses; ++i)
4527 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
4529 /* The primary base was already allocated above, so we don't
4530 need to allocate it again here. */
4531 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
4534 /* Virtual bases are added at the end (a primary virtual base
4535 will have already been added). */
4536 if (BINFO_VIRTUAL_P (base_binfo))
4539 next_field = build_base_field (rli, base_binfo,
4540 offsets, next_field);
4544 /* Go through the TYPE_METHODS of T issuing any appropriate
4545 diagnostics, figuring out which methods override which other
4546 methods, and so forth. */
4549 check_methods (tree t)
4553 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
4555 check_for_override (x, t);
4556 if (DECL_PURE_VIRTUAL_P (x) && (TREE_CODE (x) != FUNCTION_DECL || ! DECL_VINDEX (x)))
4557 error ("initializer specified for non-virtual method %q+D", x);
4558 /* The name of the field is the original field name
4559 Save this in auxiliary field for later overloading. */
4560 if (TREE_CODE (x) == FUNCTION_DECL && DECL_VINDEX (x))
4562 TYPE_POLYMORPHIC_P (t) = 1;
4563 if (DECL_PURE_VIRTUAL_P (x))
4564 vec_safe_push (CLASSTYPE_PURE_VIRTUALS (t), x);
4566 /* All user-provided destructors are non-trivial.
4567 Constructors and assignment ops are handled in
4568 grok_special_member_properties. */
4569 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
4570 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
4574 /* FN is a constructor or destructor. Clone the declaration to create
4575 a specialized in-charge or not-in-charge version, as indicated by
4579 build_clone (tree fn, tree name)
4584 /* Copy the function. */
4585 clone = copy_decl (fn);
4586 /* Reset the function name. */
4587 DECL_NAME (clone) = name;
4588 /* Remember where this function came from. */
4589 DECL_ABSTRACT_ORIGIN (clone) = fn;
4590 /* Make it easy to find the CLONE given the FN. */
4591 DECL_CHAIN (clone) = DECL_CHAIN (fn);
4592 DECL_CHAIN (fn) = clone;
4594 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
4595 if (TREE_CODE (clone) == TEMPLATE_DECL)
4597 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
4598 DECL_TEMPLATE_RESULT (clone) = result;
4599 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
4600 DECL_TI_TEMPLATE (result) = clone;
4601 TREE_TYPE (clone) = TREE_TYPE (result);
4605 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
4606 DECL_CLONED_FUNCTION (clone) = fn;
4607 /* There's no pending inline data for this function. */
4608 DECL_PENDING_INLINE_INFO (clone) = NULL;
4609 DECL_PENDING_INLINE_P (clone) = 0;
4611 /* The base-class destructor is not virtual. */
4612 if (name == base_dtor_identifier)
4614 DECL_VIRTUAL_P (clone) = 0;
4615 if (TREE_CODE (clone) != TEMPLATE_DECL)
4616 DECL_VINDEX (clone) = NULL_TREE;
4619 /* If there was an in-charge parameter, drop it from the function
4621 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4627 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4628 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4629 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
4630 /* Skip the `this' parameter. */
4631 parmtypes = TREE_CHAIN (parmtypes);
4632 /* Skip the in-charge parameter. */
4633 parmtypes = TREE_CHAIN (parmtypes);
4634 /* And the VTT parm, in a complete [cd]tor. */
4635 if (DECL_HAS_VTT_PARM_P (fn)
4636 && ! DECL_NEEDS_VTT_PARM_P (clone))
4637 parmtypes = TREE_CHAIN (parmtypes);
4638 /* If this is subobject constructor or destructor, add the vtt
4641 = build_method_type_directly (basetype,
4642 TREE_TYPE (TREE_TYPE (clone)),
4645 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
4648 = cp_build_type_attribute_variant (TREE_TYPE (clone),
4649 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
4652 /* Copy the function parameters. */
4653 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
4654 /* Remove the in-charge parameter. */
4655 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4657 DECL_CHAIN (DECL_ARGUMENTS (clone))
4658 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4659 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
4661 /* And the VTT parm, in a complete [cd]tor. */
4662 if (DECL_HAS_VTT_PARM_P (fn))
4664 if (DECL_NEEDS_VTT_PARM_P (clone))
4665 DECL_HAS_VTT_PARM_P (clone) = 1;
4668 DECL_CHAIN (DECL_ARGUMENTS (clone))
4669 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4670 DECL_HAS_VTT_PARM_P (clone) = 0;
4674 for (parms = DECL_ARGUMENTS (clone); parms; parms = DECL_CHAIN (parms))
4676 DECL_CONTEXT (parms) = clone;
4677 cxx_dup_lang_specific_decl (parms);
4680 /* Create the RTL for this function. */
4681 SET_DECL_RTL (clone, NULL);
4682 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
4685 note_decl_for_pch (clone);
4690 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4691 not invoke this function directly.
4693 For a non-thunk function, returns the address of the slot for storing
4694 the function it is a clone of. Otherwise returns NULL_TREE.
4696 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4697 cloned_function is unset. This is to support the separate
4698 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4699 on a template makes sense, but not the former. */
4702 decl_cloned_function_p (const_tree decl, bool just_testing)
4706 decl = STRIP_TEMPLATE (decl);
4708 if (TREE_CODE (decl) != FUNCTION_DECL
4709 || !DECL_LANG_SPECIFIC (decl)
4710 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
4712 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4714 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
4720 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
4721 if (just_testing && *ptr == NULL_TREE)
4727 /* Produce declarations for all appropriate clones of FN. If
4728 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4729 CLASTYPE_METHOD_VEC as well. */
4732 clone_function_decl (tree fn, int update_method_vec_p)
4736 /* Avoid inappropriate cloning. */
4738 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (fn)))
4741 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4743 /* For each constructor, we need two variants: an in-charge version
4744 and a not-in-charge version. */
4745 clone = build_clone (fn, complete_ctor_identifier);
4746 if (update_method_vec_p)
4747 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4748 clone = build_clone (fn, base_ctor_identifier);
4749 if (update_method_vec_p)
4750 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4754 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4756 /* For each destructor, we need three variants: an in-charge
4757 version, a not-in-charge version, and an in-charge deleting
4758 version. We clone the deleting version first because that
4759 means it will go second on the TYPE_METHODS list -- and that
4760 corresponds to the correct layout order in the virtual
4763 For a non-virtual destructor, we do not build a deleting
4765 if (DECL_VIRTUAL_P (fn))
4767 clone = build_clone (fn, deleting_dtor_identifier);
4768 if (update_method_vec_p)
4769 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4771 clone = build_clone (fn, complete_dtor_identifier);
4772 if (update_method_vec_p)
4773 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4774 clone = build_clone (fn, base_dtor_identifier);
4775 if (update_method_vec_p)
4776 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4779 /* Note that this is an abstract function that is never emitted. */
4780 DECL_ABSTRACT_P (fn) = true;
4783 /* DECL is an in charge constructor, which is being defined. This will
4784 have had an in class declaration, from whence clones were
4785 declared. An out-of-class definition can specify additional default
4786 arguments. As it is the clones that are involved in overload
4787 resolution, we must propagate the information from the DECL to its
4791 adjust_clone_args (tree decl)
4795 for (clone = DECL_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4796 clone = DECL_CHAIN (clone))
4798 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4799 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4800 tree decl_parms, clone_parms;
4802 clone_parms = orig_clone_parms;
4804 /* Skip the 'this' parameter. */
4805 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4806 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4808 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4809 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4810 if (DECL_HAS_VTT_PARM_P (decl))
4811 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4813 clone_parms = orig_clone_parms;
4814 if (DECL_HAS_VTT_PARM_P (clone))
4815 clone_parms = TREE_CHAIN (clone_parms);
4817 for (decl_parms = orig_decl_parms; decl_parms;
4818 decl_parms = TREE_CHAIN (decl_parms),
4819 clone_parms = TREE_CHAIN (clone_parms))
4821 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4822 TREE_TYPE (clone_parms)));
4824 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4826 /* A default parameter has been added. Adjust the
4827 clone's parameters. */
4828 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4829 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4830 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4833 clone_parms = orig_decl_parms;
4835 if (DECL_HAS_VTT_PARM_P (clone))
4837 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4838 TREE_VALUE (orig_clone_parms),
4840 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4842 type = build_method_type_directly (basetype,
4843 TREE_TYPE (TREE_TYPE (clone)),
4846 type = build_exception_variant (type, exceptions);
4848 type = cp_build_type_attribute_variant (type, attrs);
4849 TREE_TYPE (clone) = type;
4851 clone_parms = NULL_TREE;
4855 gcc_assert (!clone_parms);
4859 /* For each of the constructors and destructors in T, create an
4860 in-charge and not-in-charge variant. */
4863 clone_constructors_and_destructors (tree t)
4867 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4869 if (!CLASSTYPE_METHOD_VEC (t))
4872 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4873 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4874 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4875 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4878 /* Deduce noexcept for a destructor DTOR. */
4881 deduce_noexcept_on_destructor (tree dtor)
4883 if (!TYPE_RAISES_EXCEPTIONS (TREE_TYPE (dtor)))
4885 tree eh_spec = unevaluated_noexcept_spec ();
4886 TREE_TYPE (dtor) = build_exception_variant (TREE_TYPE (dtor), eh_spec);
4890 /* For each destructor in T, deduce noexcept:
4892 12.4/3: A declaration of a destructor that does not have an
4893 exception-specification is implicitly considered to have the
4894 same exception-specification as an implicit declaration (15.4). */
4897 deduce_noexcept_on_destructors (tree t)
4899 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4901 if (!CLASSTYPE_METHOD_VEC (t))
4904 for (tree fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4905 deduce_noexcept_on_destructor (OVL_CURRENT (fns));
4908 /* Subroutine of set_one_vmethod_tm_attributes. Search base classes
4909 of TYPE for virtual functions which FNDECL overrides. Return a
4910 mask of the tm attributes found therein. */
4913 look_for_tm_attr_overrides (tree type, tree fndecl)
4915 tree binfo = TYPE_BINFO (type);
4919 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ++ix)
4921 tree o, basetype = BINFO_TYPE (base_binfo);
4923 if (!TYPE_POLYMORPHIC_P (basetype))
4926 o = look_for_overrides_here (basetype, fndecl);
4928 found |= tm_attr_to_mask (find_tm_attribute
4929 (TYPE_ATTRIBUTES (TREE_TYPE (o))));
4931 found |= look_for_tm_attr_overrides (basetype, fndecl);
4937 /* Subroutine of set_method_tm_attributes. Handle the checks and
4938 inheritance for one virtual method FNDECL. */
4941 set_one_vmethod_tm_attributes (tree type, tree fndecl)
4946 found = look_for_tm_attr_overrides (type, fndecl);
4948 /* If FNDECL doesn't actually override anything (i.e. T is the
4949 class that first declares FNDECL virtual), then we're done. */
4953 tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (TREE_TYPE (fndecl)));
4954 have = tm_attr_to_mask (tm_attr);
4956 /* Intel STM Language Extension 3.0, Section 4.2 table 4:
4957 tm_pure must match exactly, otherwise no weakening of
4958 tm_safe > tm_callable > nothing. */
4959 /* ??? The tm_pure attribute didn't make the transition to the
4960 multivendor language spec. */
4961 if (have == TM_ATTR_PURE)
4963 if (found != TM_ATTR_PURE)
4969 /* If the overridden function is tm_pure, then FNDECL must be. */
4970 else if (found == TM_ATTR_PURE && tm_attr)
4972 /* Look for base class combinations that cannot be satisfied. */
4973 else if (found != TM_ATTR_PURE && (found & TM_ATTR_PURE))
4975 found &= ~TM_ATTR_PURE;
4977 error_at (DECL_SOURCE_LOCATION (fndecl),
4978 "method overrides both %<transaction_pure%> and %qE methods",
4979 tm_mask_to_attr (found));
4981 /* If FNDECL did not declare an attribute, then inherit the most
4983 else if (tm_attr == NULL)
4985 apply_tm_attr (fndecl, tm_mask_to_attr (found & -found));
4987 /* Otherwise validate that we're not weaker than a function
4988 that is being overridden. */
4992 if (found <= TM_ATTR_CALLABLE && have > found)
4998 error_at (DECL_SOURCE_LOCATION (fndecl),
4999 "method declared %qE overriding %qE method",
5000 tm_attr, tm_mask_to_attr (found));
5003 /* For each of the methods in T, propagate a class-level tm attribute. */
5006 set_method_tm_attributes (tree t)
5008 tree class_tm_attr, fndecl;
5010 /* Don't bother collecting tm attributes if transactional memory
5011 support is not enabled. */
5015 /* Process virtual methods first, as they inherit directly from the
5016 base virtual function and also require validation of new attributes. */
5017 if (TYPE_CONTAINS_VPTR_P (t))
5020 for (vchain = BINFO_VIRTUALS (TYPE_BINFO (t)); vchain;
5021 vchain = TREE_CHAIN (vchain))
5023 fndecl = BV_FN (vchain);
5024 if (DECL_THUNK_P (fndecl))
5025 fndecl = THUNK_TARGET (fndecl);
5026 set_one_vmethod_tm_attributes (t, fndecl);
5030 /* If the class doesn't have an attribute, nothing more to do. */
5031 class_tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (t));
5032 if (class_tm_attr == NULL)
5035 /* Any method that does not yet have a tm attribute inherits
5036 the one from the class. */
5037 for (fndecl = TYPE_METHODS (t); fndecl; fndecl = TREE_CHAIN (fndecl))
5039 if (!find_tm_attribute (TYPE_ATTRIBUTES (TREE_TYPE (fndecl))))
5040 apply_tm_attr (fndecl, class_tm_attr);
5044 /* Returns true iff class T has a user-defined constructor other than
5045 the default constructor. */
5048 type_has_user_nondefault_constructor (tree t)
5052 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
5055 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
5057 tree fn = OVL_CURRENT (fns);
5058 if (!DECL_ARTIFICIAL (fn)
5059 && (TREE_CODE (fn) == TEMPLATE_DECL
5060 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
5068 /* Returns the defaulted constructor if T has one. Otherwise, returns
5072 in_class_defaulted_default_constructor (tree t)
5076 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
5079 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
5081 tree fn = OVL_CURRENT (fns);
5083 if (DECL_DEFAULTED_IN_CLASS_P (fn))
5085 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
5086 while (args && TREE_PURPOSE (args))
5087 args = TREE_CHAIN (args);
5088 if (!args || args == void_list_node)
5096 /* Returns true iff FN is a user-provided function, i.e. user-declared
5097 and not defaulted at its first declaration; or explicit, private,
5098 protected, or non-const. */
5101 user_provided_p (tree fn)
5103 if (TREE_CODE (fn) == TEMPLATE_DECL)
5106 return (!DECL_ARTIFICIAL (fn)
5107 && !(DECL_INITIALIZED_IN_CLASS_P (fn)
5108 && (DECL_DEFAULTED_FN (fn) || DECL_DELETED_FN (fn))));
5111 /* Returns true iff class T has a user-provided constructor. */
5114 type_has_user_provided_constructor (tree t)
5118 if (!CLASS_TYPE_P (t))
5121 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
5124 /* This can happen in error cases; avoid crashing. */
5125 if (!CLASSTYPE_METHOD_VEC (t))
5128 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
5129 if (user_provided_p (OVL_CURRENT (fns)))
5135 /* Returns true iff class T has a non-user-provided (i.e. implicitly
5136 declared or explicitly defaulted in the class body) default
5140 type_has_non_user_provided_default_constructor (tree t)
5144 if (!TYPE_HAS_DEFAULT_CONSTRUCTOR (t))
5146 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t))
5149 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
5151 tree fn = OVL_CURRENT (fns);
5152 if (TREE_CODE (fn) == FUNCTION_DECL
5153 && !user_provided_p (fn)
5154 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)))
5161 /* TYPE is being used as a virtual base, and has a non-trivial move
5162 assignment. Return true if this is due to there being a user-provided
5163 move assignment in TYPE or one of its subobjects; if there isn't, then
5164 multiple move assignment can't cause any harm. */
5167 vbase_has_user_provided_move_assign (tree type)
5169 /* Does the type itself have a user-provided move assignment operator? */
5171 = lookup_fnfields_slot_nolazy (type, ansi_assopname (NOP_EXPR));
5172 fns; fns = OVL_NEXT (fns))
5174 tree fn = OVL_CURRENT (fns);
5175 if (move_fn_p (fn) && user_provided_p (fn))
5179 /* Do any of its bases? */
5180 tree binfo = TYPE_BINFO (type);
5182 for (int i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5183 if (vbase_has_user_provided_move_assign (BINFO_TYPE (base_binfo)))
5186 /* Or non-static data members? */
5187 for (tree field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
5189 if (TREE_CODE (field) == FIELD_DECL
5190 && CLASS_TYPE_P (TREE_TYPE (field))
5191 && vbase_has_user_provided_move_assign (TREE_TYPE (field)))
5199 /* If default-initialization leaves part of TYPE uninitialized, returns
5200 a DECL for the field or TYPE itself (DR 253). */
5203 default_init_uninitialized_part (tree type)
5208 type = strip_array_types (type);
5209 if (!CLASS_TYPE_P (type))
5211 if (!type_has_non_user_provided_default_constructor (type))
5213 for (binfo = TYPE_BINFO (type), i = 0;
5214 BINFO_BASE_ITERATE (binfo, i, t); ++i)
5216 r = default_init_uninitialized_part (BINFO_TYPE (t));
5220 for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t))
5221 if (TREE_CODE (t) == FIELD_DECL
5222 && !DECL_ARTIFICIAL (t)
5223 && !DECL_INITIAL (t))
5225 r = default_init_uninitialized_part (TREE_TYPE (t));
5227 return DECL_P (r) ? r : t;
5233 /* Returns true iff for class T, a trivial synthesized default constructor
5234 would be constexpr. */
5237 trivial_default_constructor_is_constexpr (tree t)
5239 /* A defaulted trivial default constructor is constexpr
5240 if there is nothing to initialize. */
5241 gcc_assert (!TYPE_HAS_COMPLEX_DFLT (t));
5242 return is_really_empty_class (t);
5245 /* Returns true iff class T has a constexpr default constructor. */
5248 type_has_constexpr_default_constructor (tree t)
5252 if (!CLASS_TYPE_P (t))
5254 /* The caller should have stripped an enclosing array. */
5255 gcc_assert (TREE_CODE (t) != ARRAY_TYPE);
5258 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t))
5260 if (!TYPE_HAS_COMPLEX_DFLT (t))
5261 return trivial_default_constructor_is_constexpr (t);
5262 /* Non-trivial, we need to check subobject constructors. */
5263 lazily_declare_fn (sfk_constructor, t);
5265 fns = locate_ctor (t);
5266 return (fns && DECL_DECLARED_CONSTEXPR_P (fns));
5269 /* Returns true iff class TYPE has a virtual destructor. */
5272 type_has_virtual_destructor (tree type)
5276 if (!CLASS_TYPE_P (type))
5279 gcc_assert (COMPLETE_TYPE_P (type));
5280 dtor = CLASSTYPE_DESTRUCTORS (type);
5281 return (dtor && DECL_VIRTUAL_P (dtor));
5284 /* Returns true iff class T has a move constructor. */
5287 type_has_move_constructor (tree t)
5291 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
5293 gcc_assert (COMPLETE_TYPE_P (t));
5294 lazily_declare_fn (sfk_move_constructor, t);
5297 if (!CLASSTYPE_METHOD_VEC (t))
5300 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
5301 if (move_fn_p (OVL_CURRENT (fns)))
5307 /* Returns true iff class T has a move assignment operator. */
5310 type_has_move_assign (tree t)
5314 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
5316 gcc_assert (COMPLETE_TYPE_P (t));
5317 lazily_declare_fn (sfk_move_assignment, t);
5320 for (fns = lookup_fnfields_slot_nolazy (t, ansi_assopname (NOP_EXPR));
5321 fns; fns = OVL_NEXT (fns))
5322 if (move_fn_p (OVL_CURRENT (fns)))
5328 /* Returns true iff class T has a move constructor that was explicitly
5329 declared in the class body. Note that this is different from
5330 "user-provided", which doesn't include functions that are defaulted in
5334 type_has_user_declared_move_constructor (tree t)
5338 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
5341 if (!CLASSTYPE_METHOD_VEC (t))
5344 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
5346 tree fn = OVL_CURRENT (fns);
5347 if (move_fn_p (fn) && !DECL_ARTIFICIAL (fn))
5354 /* Returns true iff class T has a move assignment operator that was
5355 explicitly declared in the class body. */
5358 type_has_user_declared_move_assign (tree t)
5362 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
5365 for (fns = lookup_fnfields_slot_nolazy (t, ansi_assopname (NOP_EXPR));
5366 fns; fns = OVL_NEXT (fns))
5368 tree fn = OVL_CURRENT (fns);
5369 if (move_fn_p (fn) && !DECL_ARTIFICIAL (fn))
5376 /* Nonzero if we need to build up a constructor call when initializing an
5377 object of this class, either because it has a user-declared constructor
5378 or because it doesn't have a default constructor (so we need to give an
5379 error if no initializer is provided). Use TYPE_NEEDS_CONSTRUCTING when
5380 what you care about is whether or not an object can be produced by a
5381 constructor (e.g. so we don't set TREE_READONLY on const variables of
5382 such type); use this function when what you care about is whether or not
5383 to try to call a constructor to create an object. The latter case is
5384 the former plus some cases of constructors that cannot be called. */
5387 type_build_ctor_call (tree t)
5390 if (TYPE_NEEDS_CONSTRUCTING (t))
5392 inner = strip_array_types (t);
5393 if (!CLASS_TYPE_P (inner) || ANON_AGGR_TYPE_P (inner))
5395 if (!TYPE_HAS_DEFAULT_CONSTRUCTOR (inner))
5397 if (cxx_dialect < cxx11)
5399 /* A user-declared constructor might be private, and a constructor might
5400 be trivial but deleted. */
5401 for (tree fns = lookup_fnfields_slot (inner, complete_ctor_identifier);
5402 fns; fns = OVL_NEXT (fns))
5404 tree fn = OVL_CURRENT (fns);
5405 if (!DECL_ARTIFICIAL (fn)
5406 || DECL_DELETED_FN (fn))
5412 /* Like type_build_ctor_call, but for destructors. */
5415 type_build_dtor_call (tree t)
5418 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
5420 inner = strip_array_types (t);
5421 if (!CLASS_TYPE_P (inner) || ANON_AGGR_TYPE_P (inner)
5422 || !COMPLETE_TYPE_P (inner))
5424 if (cxx_dialect < cxx11)
5426 /* A user-declared destructor might be private, and a destructor might
5427 be trivial but deleted. */
5428 for (tree fns = lookup_fnfields_slot (inner, complete_dtor_identifier);
5429 fns; fns = OVL_NEXT (fns))
5431 tree fn = OVL_CURRENT (fns);
5432 if (!DECL_ARTIFICIAL (fn)
5433 || DECL_DELETED_FN (fn))
5439 /* Remove all zero-width bit-fields from T. */
5442 remove_zero_width_bit_fields (tree t)
5446 fieldsp = &TYPE_FIELDS (t);
5449 if (TREE_CODE (*fieldsp) == FIELD_DECL
5450 && DECL_C_BIT_FIELD (*fieldsp)
5451 /* We should not be confused by the fact that grokbitfield
5452 temporarily sets the width of the bit field into
5453 DECL_INITIAL (*fieldsp).
5454 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
5456 && (DECL_SIZE (*fieldsp) == NULL_TREE
5457 || integer_zerop (DECL_SIZE (*fieldsp))))
5458 *fieldsp = DECL_CHAIN (*fieldsp);
5460 fieldsp = &DECL_CHAIN (*fieldsp);
5464 /* Returns TRUE iff we need a cookie when dynamically allocating an
5465 array whose elements have the indicated class TYPE. */
5468 type_requires_array_cookie (tree type)
5471 bool has_two_argument_delete_p = false;
5473 gcc_assert (CLASS_TYPE_P (type));
5475 /* If there's a non-trivial destructor, we need a cookie. In order
5476 to iterate through the array calling the destructor for each
5477 element, we'll have to know how many elements there are. */
5478 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
5481 /* If the usual deallocation function is a two-argument whose second
5482 argument is of type `size_t', then we have to pass the size of
5483 the array to the deallocation function, so we will need to store
5485 fns = lookup_fnfields (TYPE_BINFO (type),
5486 ansi_opname (VEC_DELETE_EXPR),
5488 /* If there are no `operator []' members, or the lookup is
5489 ambiguous, then we don't need a cookie. */
5490 if (!fns || fns == error_mark_node)
5492 /* Loop through all of the functions. */
5493 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
5498 /* Select the current function. */
5499 fn = OVL_CURRENT (fns);
5500 /* See if this function is a one-argument delete function. If
5501 it is, then it will be the usual deallocation function. */
5502 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
5503 if (second_parm == void_list_node)
5505 /* Do not consider this function if its second argument is an
5509 /* Otherwise, if we have a two-argument function and the second
5510 argument is `size_t', it will be the usual deallocation
5511 function -- unless there is one-argument function, too. */
5512 if (TREE_CHAIN (second_parm) == void_list_node
5513 && same_type_p (TREE_VALUE (second_parm), size_type_node))
5514 has_two_argument_delete_p = true;
5517 return has_two_argument_delete_p;
5520 /* Finish computing the `literal type' property of class type T.
5522 At this point, we have already processed base classes and
5523 non-static data members. We need to check whether the copy
5524 constructor is trivial, the destructor is trivial, and there
5525 is a trivial default constructor or at least one constexpr
5526 constructor other than the copy constructor. */
5529 finalize_literal_type_property (tree t)
5533 if (cxx_dialect < cxx11
5534 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
5535 CLASSTYPE_LITERAL_P (t) = false;
5536 else if (CLASSTYPE_LITERAL_P (t) && !TYPE_HAS_TRIVIAL_DFLT (t)
5537 && CLASSTYPE_NON_AGGREGATE (t)
5538 && !TYPE_HAS_CONSTEXPR_CTOR (t))
5539 CLASSTYPE_LITERAL_P (t) = false;
5541 if (!CLASSTYPE_LITERAL_P (t))
5542 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
5543 if (DECL_DECLARED_CONSTEXPR_P (fn)
5544 && TREE_CODE (fn) != TEMPLATE_DECL
5545 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
5546 && !DECL_CONSTRUCTOR_P (fn))
5548 DECL_DECLARED_CONSTEXPR_P (fn) = false;
5549 if (!DECL_GENERATED_P (fn))
5551 error ("enclosing class of constexpr non-static member "
5552 "function %q+#D is not a literal type", fn);
5553 explain_non_literal_class (t);
5558 /* T is a non-literal type used in a context which requires a constant
5559 expression. Explain why it isn't literal. */
5562 explain_non_literal_class (tree t)
5564 static hash_set<tree> *diagnosed;
5566 if (!CLASS_TYPE_P (t))
5568 t = TYPE_MAIN_VARIANT (t);
5570 if (diagnosed == NULL)
5571 diagnosed = new hash_set<tree>;
5572 if (diagnosed->add (t))
5573 /* Already explained. */
5576 inform (0, "%q+T is not literal because:", t);
5577 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
5578 inform (0, " %q+T has a non-trivial destructor", t);
5579 else if (CLASSTYPE_NON_AGGREGATE (t)
5580 && !TYPE_HAS_TRIVIAL_DFLT (t)
5581 && !TYPE_HAS_CONSTEXPR_CTOR (t))
5583 inform (0, " %q+T is not an aggregate, does not have a trivial "
5584 "default constructor, and has no constexpr constructor that "
5585 "is not a copy or move constructor", t);
5586 if (type_has_non_user_provided_default_constructor (t))
5588 /* Note that we can't simply call locate_ctor because when the
5589 constructor is deleted it just returns NULL_TREE. */
5591 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
5593 tree fn = OVL_CURRENT (fns);
5594 tree parms = TYPE_ARG_TYPES (TREE_TYPE (fn));
5596 parms = skip_artificial_parms_for (fn, parms);
5598 if (sufficient_parms_p (parms))
5600 if (DECL_DELETED_FN (fn))
5601 maybe_explain_implicit_delete (fn);
5603 explain_invalid_constexpr_fn (fn);
5611 tree binfo, base_binfo, field; int i;
5612 for (binfo = TYPE_BINFO (t), i = 0;
5613 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
5615 tree basetype = TREE_TYPE (base_binfo);
5616 if (!CLASSTYPE_LITERAL_P (basetype))
5618 inform (0, " base class %qT of %q+T is non-literal",
5620 explain_non_literal_class (basetype);
5624 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5627 if (TREE_CODE (field) != FIELD_DECL)
5629 ftype = TREE_TYPE (field);
5630 if (!literal_type_p (ftype))
5632 inform (0, " non-static data member %q+D has "
5633 "non-literal type", field);
5634 if (CLASS_TYPE_P (ftype))
5635 explain_non_literal_class (ftype);
5637 if (CP_TYPE_VOLATILE_P (ftype))
5638 inform (0, " non-static data member %q+D has "
5639 "volatile type", field);
5644 /* Check the validity of the bases and members declared in T. Add any
5645 implicitly-generated functions (like copy-constructors and
5646 assignment operators). Compute various flag bits (like
5647 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
5648 level: i.e., independently of the ABI in use. */
5651 check_bases_and_members (tree t)
5653 /* Nonzero if the implicitly generated copy constructor should take
5654 a non-const reference argument. */
5655 int cant_have_const_ctor;
5656 /* Nonzero if the implicitly generated assignment operator
5657 should take a non-const reference argument. */
5658 int no_const_asn_ref;
5660 bool saved_complex_asn_ref;
5661 bool saved_nontrivial_dtor;
5664 /* By default, we use const reference arguments and generate default
5666 cant_have_const_ctor = 0;
5667 no_const_asn_ref = 0;
5669 /* Check all the base-classes. */
5670 check_bases (t, &cant_have_const_ctor,
5673 /* Deduce noexcept on destructors. This needs to happen after we've set
5674 triviality flags appropriately for our bases. */
5675 if (cxx_dialect >= cxx11)
5676 deduce_noexcept_on_destructors (t);
5678 /* Check all the method declarations. */
5681 /* Save the initial values of these flags which only indicate whether
5682 or not the class has user-provided functions. As we analyze the
5683 bases and members we can set these flags for other reasons. */
5684 saved_complex_asn_ref = TYPE_HAS_COMPLEX_COPY_ASSIGN (t);
5685 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
5687 /* Check all the data member declarations. We cannot call
5688 check_field_decls until we have called check_bases check_methods,
5689 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
5690 being set appropriately. */
5691 check_field_decls (t, &access_decls,
5692 &cant_have_const_ctor,
5695 /* A nearly-empty class has to be vptr-containing; a nearly empty
5696 class contains just a vptr. */
5697 if (!TYPE_CONTAINS_VPTR_P (t))
5698 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
5700 /* Do some bookkeeping that will guide the generation of implicitly
5701 declared member functions. */
5702 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
5703 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
5704 /* We need to call a constructor for this class if it has a
5705 user-provided constructor, or if the default constructor is going
5706 to initialize the vptr. (This is not an if-and-only-if;
5707 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
5708 themselves need constructing.) */
5709 TYPE_NEEDS_CONSTRUCTING (t)
5710 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
5713 An aggregate is an array or a class with no user-provided
5714 constructors ... and no virtual functions.
5716 Again, other conditions for being an aggregate are checked
5718 CLASSTYPE_NON_AGGREGATE (t)
5719 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
5720 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
5721 retain the old definition internally for ABI reasons. */
5722 CLASSTYPE_NON_LAYOUT_POD_P (t)
5723 |= (CLASSTYPE_NON_AGGREGATE (t)
5724 || saved_nontrivial_dtor || saved_complex_asn_ref);
5725 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
5726 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
5727 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
5728 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
5730 /* If the only explicitly declared default constructor is user-provided,
5731 set TYPE_HAS_COMPLEX_DFLT. */
5732 if (!TYPE_HAS_COMPLEX_DFLT (t)
5733 && TYPE_HAS_DEFAULT_CONSTRUCTOR (t)
5734 && !type_has_non_user_provided_default_constructor (t))
5735 TYPE_HAS_COMPLEX_DFLT (t) = true;
5737 /* Warn if a public base of a polymorphic type has an accessible
5738 non-virtual destructor. It is only now that we know the class is
5739 polymorphic. Although a polymorphic base will have a already
5740 been diagnosed during its definition, we warn on use too. */
5741 if (TYPE_POLYMORPHIC_P (t) && warn_nonvdtor)
5743 tree binfo = TYPE_BINFO (t);
5744 vec<tree, va_gc> *accesses = BINFO_BASE_ACCESSES (binfo);
5748 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
5750 tree basetype = TREE_TYPE (base_binfo);
5752 if ((*accesses)[i] == access_public_node
5753 && (TYPE_POLYMORPHIC_P (basetype) || warn_ecpp)
5754 && accessible_nvdtor_p (basetype))
5755 warning (OPT_Wnon_virtual_dtor,
5756 "base class %q#T has accessible non-virtual destructor",
5761 /* If the class has no user-declared constructor, but does have
5762 non-static const or reference data members that can never be
5763 initialized, issue a warning. */
5764 if (warn_uninitialized
5765 /* Classes with user-declared constructors are presumed to
5766 initialize these members. */
5767 && !TYPE_HAS_USER_CONSTRUCTOR (t)
5768 /* Aggregates can be initialized with brace-enclosed
5770 && CLASSTYPE_NON_AGGREGATE (t))
5774 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5778 if (TREE_CODE (field) != FIELD_DECL
5779 || DECL_INITIAL (field) != NULL_TREE)
5782 type = TREE_TYPE (field);
5783 if (TREE_CODE (type) == REFERENCE_TYPE)
5784 warning (OPT_Wuninitialized, "non-static reference %q+#D "
5785 "in class without a constructor", field);
5786 else if (CP_TYPE_CONST_P (type)
5787 && (!CLASS_TYPE_P (type)
5788 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
5789 warning (OPT_Wuninitialized, "non-static const member %q+#D "
5790 "in class without a constructor", field);
5794 /* Synthesize any needed methods. */
5795 add_implicitly_declared_members (t, &access_decls,
5796 cant_have_const_ctor,
5799 /* Check defaulted declarations here so we have cant_have_const_ctor
5800 and don't need to worry about clones. */
5801 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
5802 if (!DECL_ARTIFICIAL (fn) && DECL_DEFAULTED_IN_CLASS_P (fn))
5804 int copy = copy_fn_p (fn);
5808 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
5809 : !no_const_asn_ref);
5810 bool fn_const_p = (copy == 2);
5812 if (fn_const_p && !imp_const_p)
5813 /* If the function is defaulted outside the class, we just
5814 give the synthesis error. */
5815 error ("%q+D declared to take const reference, but implicit "
5816 "declaration would take non-const", fn);
5818 defaulted_late_check (fn);
5821 if (LAMBDA_TYPE_P (t))
5823 /* "This class type is not an aggregate." */
5824 CLASSTYPE_NON_AGGREGATE (t) = 1;
5827 /* Compute the 'literal type' property before we
5828 do anything with non-static member functions. */
5829 finalize_literal_type_property (t);
5831 /* Create the in-charge and not-in-charge variants of constructors
5833 clone_constructors_and_destructors (t);
5835 /* Process the using-declarations. */
5836 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
5837 handle_using_decl (TREE_VALUE (access_decls), t);
5839 /* Build and sort the CLASSTYPE_METHOD_VEC. */
5840 finish_struct_methods (t);
5842 /* Figure out whether or not we will need a cookie when dynamically
5843 allocating an array of this type. */
5844 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
5845 = type_requires_array_cookie (t);
5848 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
5849 accordingly. If a new vfield was created (because T doesn't have a
5850 primary base class), then the newly created field is returned. It
5851 is not added to the TYPE_FIELDS list; it is the caller's
5852 responsibility to do that. Accumulate declared virtual functions
5856 create_vtable_ptr (tree t, tree* virtuals_p)
5860 /* Collect the virtual functions declared in T. */
5861 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
5862 if (TREE_CODE (fn) == FUNCTION_DECL
5863 && DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
5864 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
5866 tree new_virtual = make_node (TREE_LIST);
5868 BV_FN (new_virtual) = fn;
5869 BV_DELTA (new_virtual) = integer_zero_node;
5870 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
5872 TREE_CHAIN (new_virtual) = *virtuals_p;
5873 *virtuals_p = new_virtual;
5876 /* If we couldn't find an appropriate base class, create a new field
5877 here. Even if there weren't any new virtual functions, we might need a
5878 new virtual function table if we're supposed to include vptrs in
5879 all classes that need them. */
5880 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
5882 /* We build this decl with vtbl_ptr_type_node, which is a
5883 `vtable_entry_type*'. It might seem more precise to use
5884 `vtable_entry_type (*)[N]' where N is the number of virtual
5885 functions. However, that would require the vtable pointer in
5886 base classes to have a different type than the vtable pointer
5887 in derived classes. We could make that happen, but that
5888 still wouldn't solve all the problems. In particular, the
5889 type-based alias analysis code would decide that assignments
5890 to the base class vtable pointer can't alias assignments to
5891 the derived class vtable pointer, since they have different
5892 types. Thus, in a derived class destructor, where the base
5893 class constructor was inlined, we could generate bad code for
5894 setting up the vtable pointer.
5896 Therefore, we use one type for all vtable pointers. We still
5897 use a type-correct type; it's just doesn't indicate the array
5898 bounds. That's better than using `void*' or some such; it's
5899 cleaner, and it let's the alias analysis code know that these
5900 stores cannot alias stores to void*! */
5903 field = build_decl (input_location,
5904 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
5905 DECL_VIRTUAL_P (field) = 1;
5906 DECL_ARTIFICIAL (field) = 1;
5907 DECL_FIELD_CONTEXT (field) = t;
5908 DECL_FCONTEXT (field) = t;
5909 if (TYPE_PACKED (t))
5910 DECL_PACKED (field) = 1;
5912 TYPE_VFIELD (t) = field;
5914 /* This class is non-empty. */
5915 CLASSTYPE_EMPTY_P (t) = 0;
5923 /* Add OFFSET to all base types of BINFO which is a base in the
5924 hierarchy dominated by T.
5926 OFFSET, which is a type offset, is number of bytes. */
5929 propagate_binfo_offsets (tree binfo, tree offset)
5935 /* Update BINFO's offset. */
5936 BINFO_OFFSET (binfo)
5937 = convert (sizetype,
5938 size_binop (PLUS_EXPR,
5939 convert (ssizetype, BINFO_OFFSET (binfo)),
5942 /* Find the primary base class. */
5943 primary_binfo = get_primary_binfo (binfo);
5945 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
5946 propagate_binfo_offsets (primary_binfo, offset);
5948 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
5950 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5952 /* Don't do the primary base twice. */
5953 if (base_binfo == primary_binfo)
5956 if (BINFO_VIRTUAL_P (base_binfo))
5959 propagate_binfo_offsets (base_binfo, offset);
5963 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
5964 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
5965 empty subobjects of T. */
5968 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
5974 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
5977 /* Find the last field. The artificial fields created for virtual
5978 bases will go after the last extant field to date. */
5979 next_field = &TYPE_FIELDS (t);
5981 next_field = &DECL_CHAIN (*next_field);
5983 /* Go through the virtual bases, allocating space for each virtual
5984 base that is not already a primary base class. These are
5985 allocated in inheritance graph order. */
5986 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
5988 if (!BINFO_VIRTUAL_P (vbase))
5991 if (!BINFO_PRIMARY_P (vbase))
5993 /* This virtual base is not a primary base of any class in the
5994 hierarchy, so we have to add space for it. */
5995 next_field = build_base_field (rli, vbase,
5996 offsets, next_field);
6001 /* Returns the offset of the byte just past the end of the base class
6005 end_of_base (tree binfo)
6009 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
6010 size = TYPE_SIZE_UNIT (char_type_node);
6011 else if (is_empty_class (BINFO_TYPE (binfo)))
6012 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
6013 allocate some space for it. It cannot have virtual bases, so
6014 TYPE_SIZE_UNIT is fine. */
6015 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
6017 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
6019 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
6022 /* Returns the offset of the byte just past the end of the base class
6023 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
6024 only non-virtual bases are included. */
6027 end_of_class (tree t, int include_virtuals_p)
6029 tree result = size_zero_node;
6030 vec<tree, va_gc> *vbases;
6036 for (binfo = TYPE_BINFO (t), i = 0;
6037 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6039 if (!include_virtuals_p
6040 && BINFO_VIRTUAL_P (base_binfo)
6041 && (!BINFO_PRIMARY_P (base_binfo)
6042 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
6045 offset = end_of_base (base_binfo);
6046 if (tree_int_cst_lt (result, offset))
6050 if (include_virtuals_p)
6051 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
6052 vec_safe_iterate (vbases, i, &base_binfo); i++)
6054 offset = end_of_base (base_binfo);
6055 if (tree_int_cst_lt (result, offset))
6062 /* Warn about bases of T that are inaccessible because they are
6063 ambiguous. For example:
6066 struct T : public S {};
6067 struct U : public S, public T {};
6069 Here, `(S*) new U' is not allowed because there are two `S'
6073 warn_about_ambiguous_bases (tree t)
6076 vec<tree, va_gc> *vbases;
6081 /* If there are no repeated bases, nothing can be ambiguous. */
6082 if (!CLASSTYPE_REPEATED_BASE_P (t))
6085 /* Check direct bases. */
6086 for (binfo = TYPE_BINFO (t), i = 0;
6087 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6089 basetype = BINFO_TYPE (base_binfo);
6091 if (!uniquely_derived_from_p (basetype, t))
6092 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
6096 /* Check for ambiguous virtual bases. */
6098 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
6099 vec_safe_iterate (vbases, i, &binfo); i++)
6101 basetype = BINFO_TYPE (binfo);
6103 if (!uniquely_derived_from_p (basetype, t))
6104 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due "
6105 "to ambiguity", basetype, t);
6109 /* Compare two INTEGER_CSTs K1 and K2. */
6112 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
6114 return tree_int_cst_compare ((tree) k1, (tree) k2);
6117 /* Increase the size indicated in RLI to account for empty classes
6118 that are "off the end" of the class. */
6121 include_empty_classes (record_layout_info rli)
6126 /* It might be the case that we grew the class to allocate a
6127 zero-sized base class. That won't be reflected in RLI, yet,
6128 because we are willing to overlay multiple bases at the same
6129 offset. However, now we need to make sure that RLI is big enough
6130 to reflect the entire class. */
6131 eoc = end_of_class (rli->t,
6132 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
6133 rli_size = rli_size_unit_so_far (rli);
6134 if (TREE_CODE (rli_size) == INTEGER_CST
6135 && tree_int_cst_lt (rli_size, eoc))
6137 /* The size should have been rounded to a whole byte. */
6138 gcc_assert (tree_int_cst_equal
6139 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
6141 = size_binop (PLUS_EXPR,
6143 size_binop (MULT_EXPR,
6144 convert (bitsizetype,
6145 size_binop (MINUS_EXPR,
6147 bitsize_int (BITS_PER_UNIT)));
6148 normalize_rli (rli);
6152 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
6153 BINFO_OFFSETs for all of the base-classes. Position the vtable
6154 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
6157 layout_class_type (tree t, tree *virtuals_p)
6159 tree non_static_data_members;
6162 record_layout_info rli;
6163 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
6164 types that appear at that offset. */
6165 splay_tree empty_base_offsets;
6166 /* True if the last field laid out was a bit-field. */
6167 bool last_field_was_bitfield = false;
6168 /* The location at which the next field should be inserted. */
6170 /* T, as a base class. */
6173 /* Keep track of the first non-static data member. */
6174 non_static_data_members = TYPE_FIELDS (t);
6176 /* Start laying out the record. */
6177 rli = start_record_layout (t);
6179 /* Mark all the primary bases in the hierarchy. */
6180 determine_primary_bases (t);
6182 /* Create a pointer to our virtual function table. */
6183 vptr = create_vtable_ptr (t, virtuals_p);
6185 /* The vptr is always the first thing in the class. */
6188 DECL_CHAIN (vptr) = TYPE_FIELDS (t);
6189 TYPE_FIELDS (t) = vptr;
6190 next_field = &DECL_CHAIN (vptr);
6191 place_field (rli, vptr);
6194 next_field = &TYPE_FIELDS (t);
6196 /* Build FIELD_DECLs for all of the non-virtual base-types. */
6197 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
6199 build_base_fields (rli, empty_base_offsets, next_field);
6201 /* Layout the non-static data members. */
6202 for (field = non_static_data_members; field; field = DECL_CHAIN (field))
6207 /* We still pass things that aren't non-static data members to
6208 the back end, in case it wants to do something with them. */
6209 if (TREE_CODE (field) != FIELD_DECL)
6211 place_field (rli, field);
6212 /* If the static data member has incomplete type, keep track
6213 of it so that it can be completed later. (The handling
6214 of pending statics in finish_record_layout is
6215 insufficient; consider:
6218 struct S2 { static S1 s1; };
6220 At this point, finish_record_layout will be called, but
6221 S1 is still incomplete.) */
6224 maybe_register_incomplete_var (field);
6225 /* The visibility of static data members is determined
6226 at their point of declaration, not their point of
6228 determine_visibility (field);
6233 type = TREE_TYPE (field);
6234 if (type == error_mark_node)
6237 padding = NULL_TREE;
6239 /* If this field is a bit-field whose width is greater than its
6240 type, then there are some special rules for allocating
6242 if (DECL_C_BIT_FIELD (field)
6243 && tree_int_cst_lt (TYPE_SIZE (type), DECL_SIZE (field)))
6247 bool was_unnamed_p = false;
6248 /* We must allocate the bits as if suitably aligned for the
6249 longest integer type that fits in this many bits. type
6250 of the field. Then, we are supposed to use the left over
6251 bits as additional padding. */
6252 for (itk = itk_char; itk != itk_none; ++itk)
6253 if (integer_types[itk] != NULL_TREE
6254 && (tree_int_cst_lt (size_int (MAX_FIXED_MODE_SIZE),
6255 TYPE_SIZE (integer_types[itk]))
6256 || tree_int_cst_lt (DECL_SIZE (field),
6257 TYPE_SIZE (integer_types[itk]))))
6260 /* ITK now indicates a type that is too large for the
6261 field. We have to back up by one to find the largest
6266 integer_type = integer_types[itk];
6267 } while (itk > 0 && integer_type == NULL_TREE);
6269 /* Figure out how much additional padding is required. */
6270 if (tree_int_cst_lt (TYPE_SIZE (integer_type), DECL_SIZE (field)))
6272 if (TREE_CODE (t) == UNION_TYPE)
6273 /* In a union, the padding field must have the full width
6274 of the bit-field; all fields start at offset zero. */
6275 padding = DECL_SIZE (field);
6277 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
6278 TYPE_SIZE (integer_type));
6280 #ifdef PCC_BITFIELD_TYPE_MATTERS
6281 /* An unnamed bitfield does not normally affect the
6282 alignment of the containing class on a target where
6283 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
6284 make any exceptions for unnamed bitfields when the
6285 bitfields are longer than their types. Therefore, we
6286 temporarily give the field a name. */
6287 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
6289 was_unnamed_p = true;
6290 DECL_NAME (field) = make_anon_name ();
6293 DECL_SIZE (field) = TYPE_SIZE (integer_type);
6294 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
6295 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
6296 layout_nonempty_base_or_field (rli, field, NULL_TREE,
6297 empty_base_offsets);
6299 DECL_NAME (field) = NULL_TREE;
6300 /* Now that layout has been performed, set the size of the
6301 field to the size of its declared type; the rest of the
6302 field is effectively invisible. */
6303 DECL_SIZE (field) = TYPE_SIZE (type);
6304 /* We must also reset the DECL_MODE of the field. */
6305 DECL_MODE (field) = TYPE_MODE (type);
6308 layout_nonempty_base_or_field (rli, field, NULL_TREE,
6309 empty_base_offsets);
6311 /* Remember the location of any empty classes in FIELD. */
6312 record_subobject_offsets (TREE_TYPE (field),
6313 byte_position(field),
6315 /*is_data_member=*/true);
6317 /* If a bit-field does not immediately follow another bit-field,
6318 and yet it starts in the middle of a byte, we have failed to
6319 comply with the ABI. */
6321 && DECL_C_BIT_FIELD (field)
6322 /* The TREE_NO_WARNING flag gets set by Objective-C when
6323 laying out an Objective-C class. The ObjC ABI differs
6324 from the C++ ABI, and so we do not want a warning
6326 && !TREE_NO_WARNING (field)
6327 && !last_field_was_bitfield
6328 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
6329 DECL_FIELD_BIT_OFFSET (field),
6330 bitsize_unit_node)))
6331 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
6332 "change in a future version of GCC", field);
6334 /* The middle end uses the type of expressions to determine the
6335 possible range of expression values. In order to optimize
6336 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
6337 must be made aware of the width of "i", via its type.
6339 Because C++ does not have integer types of arbitrary width,
6340 we must (for the purposes of the front end) convert from the
6341 type assigned here to the declared type of the bitfield
6342 whenever a bitfield expression is used as an rvalue.
6343 Similarly, when assigning a value to a bitfield, the value
6344 must be converted to the type given the bitfield here. */
6345 if (DECL_C_BIT_FIELD (field))
6347 unsigned HOST_WIDE_INT width;
6348 tree ftype = TREE_TYPE (field);
6349 width = tree_to_uhwi (DECL_SIZE (field));
6350 if (width != TYPE_PRECISION (ftype))
6353 = c_build_bitfield_integer_type (width,
6354 TYPE_UNSIGNED (ftype));
6356 = cp_build_qualified_type (TREE_TYPE (field),
6357 cp_type_quals (ftype));
6361 /* If we needed additional padding after this field, add it
6367 padding_field = build_decl (input_location,
6371 DECL_BIT_FIELD (padding_field) = 1;
6372 DECL_SIZE (padding_field) = padding;
6373 DECL_CONTEXT (padding_field) = t;
6374 DECL_ARTIFICIAL (padding_field) = 1;
6375 DECL_IGNORED_P (padding_field) = 1;
6376 layout_nonempty_base_or_field (rli, padding_field,
6378 empty_base_offsets);
6381 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
6384 if (!integer_zerop (rli->bitpos))
6386 /* Make sure that we are on a byte boundary so that the size of
6387 the class without virtual bases will always be a round number
6389 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
6390 normalize_rli (rli);
6393 /* Delete all zero-width bit-fields from the list of fields. Now
6394 that the type is laid out they are no longer important. */
6395 remove_zero_width_bit_fields (t);
6397 /* Create the version of T used for virtual bases. We do not use
6398 make_class_type for this version; this is an artificial type. For
6399 a POD type, we just reuse T. */
6400 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
6402 base_t = make_node (TREE_CODE (t));
6404 /* Set the size and alignment for the new type. */
6407 /* If the ABI version is not at least two, and the last
6408 field was a bit-field, RLI may not be on a byte
6409 boundary. In particular, rli_size_unit_so_far might
6410 indicate the last complete byte, while rli_size_so_far
6411 indicates the total number of bits used. Therefore,
6412 rli_size_so_far, rather than rli_size_unit_so_far, is
6413 used to compute TYPE_SIZE_UNIT. */
6414 eoc = end_of_class (t, /*include_virtuals_p=*/0);
6415 TYPE_SIZE_UNIT (base_t)
6416 = size_binop (MAX_EXPR,
6418 size_binop (CEIL_DIV_EXPR,
6419 rli_size_so_far (rli),
6420 bitsize_int (BITS_PER_UNIT))),
6423 = size_binop (MAX_EXPR,
6424 rli_size_so_far (rli),
6425 size_binop (MULT_EXPR,
6426 convert (bitsizetype, eoc),
6427 bitsize_int (BITS_PER_UNIT)));
6428 TYPE_ALIGN (base_t) = rli->record_align;
6429 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
6431 /* Copy the fields from T. */
6432 next_field = &TYPE_FIELDS (base_t);
6433 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
6434 if (TREE_CODE (field) == FIELD_DECL)
6436 *next_field = build_decl (input_location,
6440 DECL_CONTEXT (*next_field) = base_t;
6441 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
6442 DECL_FIELD_BIT_OFFSET (*next_field)
6443 = DECL_FIELD_BIT_OFFSET (field);
6444 DECL_SIZE (*next_field) = DECL_SIZE (field);
6445 DECL_MODE (*next_field) = DECL_MODE (field);
6446 next_field = &DECL_CHAIN (*next_field);
6449 /* Record the base version of the type. */
6450 CLASSTYPE_AS_BASE (t) = base_t;
6451 TYPE_CONTEXT (base_t) = t;
6454 CLASSTYPE_AS_BASE (t) = t;
6456 /* Every empty class contains an empty class. */
6457 if (CLASSTYPE_EMPTY_P (t))
6458 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
6460 /* Set the TYPE_DECL for this type to contain the right
6461 value for DECL_OFFSET, so that we can use it as part
6462 of a COMPONENT_REF for multiple inheritance. */
6463 layout_decl (TYPE_MAIN_DECL (t), 0);
6465 /* Now fix up any virtual base class types that we left lying
6466 around. We must get these done before we try to lay out the
6467 virtual function table. As a side-effect, this will remove the
6468 base subobject fields. */
6469 layout_virtual_bases (rli, empty_base_offsets);
6471 /* Make sure that empty classes are reflected in RLI at this
6473 include_empty_classes(rli);
6475 /* Make sure not to create any structures with zero size. */
6476 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
6478 build_decl (input_location,
6479 FIELD_DECL, NULL_TREE, char_type_node));
6481 /* If this is a non-POD, declaring it packed makes a difference to how it
6482 can be used as a field; don't let finalize_record_size undo it. */
6483 if (TYPE_PACKED (t) && !layout_pod_type_p (t))
6484 rli->packed_maybe_necessary = true;
6486 /* Let the back end lay out the type. */
6487 finish_record_layout (rli, /*free_p=*/true);
6489 if (TYPE_SIZE_UNIT (t)
6490 && TREE_CODE (TYPE_SIZE_UNIT (t)) == INTEGER_CST
6491 && !TREE_OVERFLOW (TYPE_SIZE_UNIT (t))
6492 && !valid_constant_size_p (TYPE_SIZE_UNIT (t)))
6493 error ("type %qT is too large", t);
6495 /* Warn about bases that can't be talked about due to ambiguity. */
6496 warn_about_ambiguous_bases (t);
6498 /* Now that we're done with layout, give the base fields the real types. */
6499 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
6500 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
6501 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
6504 splay_tree_delete (empty_base_offsets);
6506 if (CLASSTYPE_EMPTY_P (t)
6507 && tree_int_cst_lt (sizeof_biggest_empty_class,
6508 TYPE_SIZE_UNIT (t)))
6509 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
6512 /* Determine the "key method" for the class type indicated by TYPE,
6513 and set CLASSTYPE_KEY_METHOD accordingly. */
6516 determine_key_method (tree type)
6520 if (TYPE_FOR_JAVA (type)
6521 || processing_template_decl
6522 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
6523 || CLASSTYPE_INTERFACE_KNOWN (type))
6526 /* The key method is the first non-pure virtual function that is not
6527 inline at the point of class definition. On some targets the
6528 key function may not be inline; those targets should not call
6529 this function until the end of the translation unit. */
6530 for (method = TYPE_METHODS (type); method != NULL_TREE;
6531 method = DECL_CHAIN (method))
6532 if (TREE_CODE (method) == FUNCTION_DECL
6533 && DECL_VINDEX (method) != NULL_TREE
6534 && ! DECL_DECLARED_INLINE_P (method)
6535 && ! DECL_PURE_VIRTUAL_P (method))
6537 CLASSTYPE_KEY_METHOD (type) = method;
6545 /* Allocate and return an instance of struct sorted_fields_type with
6548 static struct sorted_fields_type *
6549 sorted_fields_type_new (int n)
6551 struct sorted_fields_type *sft;
6552 sft = (sorted_fields_type *) ggc_internal_alloc (sizeof (sorted_fields_type)
6553 + n * sizeof (tree));
6560 /* Perform processing required when the definition of T (a class type)
6564 finish_struct_1 (tree t)
6567 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
6568 tree virtuals = NULL_TREE;
6570 if (COMPLETE_TYPE_P (t))
6572 gcc_assert (MAYBE_CLASS_TYPE_P (t));
6573 error ("redefinition of %q#T", t);
6578 /* If this type was previously laid out as a forward reference,
6579 make sure we lay it out again. */
6580 TYPE_SIZE (t) = NULL_TREE;
6581 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
6583 /* Make assumptions about the class; we'll reset the flags if
6585 CLASSTYPE_EMPTY_P (t) = 1;
6586 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
6587 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
6588 CLASSTYPE_LITERAL_P (t) = true;
6590 /* Do end-of-class semantic processing: checking the validity of the
6591 bases and members and add implicitly generated methods. */
6592 check_bases_and_members (t);
6594 /* Find the key method. */
6595 if (TYPE_CONTAINS_VPTR_P (t))
6597 /* The Itanium C++ ABI permits the key method to be chosen when
6598 the class is defined -- even though the key method so
6599 selected may later turn out to be an inline function. On
6600 some systems (such as ARM Symbian OS) the key method cannot
6601 be determined until the end of the translation unit. On such
6602 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
6603 will cause the class to be added to KEYED_CLASSES. Then, in
6604 finish_file we will determine the key method. */
6605 if (targetm.cxx.key_method_may_be_inline ())
6606 determine_key_method (t);
6608 /* If a polymorphic class has no key method, we may emit the vtable
6609 in every translation unit where the class definition appears. If
6610 we're devirtualizing, we can look into the vtable even if we
6611 aren't emitting it. */
6612 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
6613 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
6616 /* Layout the class itself. */
6617 layout_class_type (t, &virtuals);
6618 if (CLASSTYPE_AS_BASE (t) != t)
6619 /* We use the base type for trivial assignments, and hence it
6621 compute_record_mode (CLASSTYPE_AS_BASE (t));
6623 virtuals = modify_all_vtables (t, nreverse (virtuals));
6625 /* If necessary, create the primary vtable for this class. */
6626 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
6628 /* We must enter these virtuals into the table. */
6629 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
6630 build_primary_vtable (NULL_TREE, t);
6631 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
6632 /* Here we know enough to change the type of our virtual
6633 function table, but we will wait until later this function. */
6634 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
6636 /* If we're warning about ABI tags, check the types of the new
6637 virtual functions. */
6639 for (tree v = virtuals; v; v = TREE_CHAIN (v))
6640 check_abi_tags (t, TREE_VALUE (v));
6643 if (TYPE_CONTAINS_VPTR_P (t))
6648 if (BINFO_VTABLE (TYPE_BINFO (t)))
6649 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
6650 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
6651 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
6653 /* Add entries for virtual functions introduced by this class. */
6654 BINFO_VIRTUALS (TYPE_BINFO (t))
6655 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
6657 /* Set DECL_VINDEX for all functions declared in this class. */
6658 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
6660 fn = TREE_CHAIN (fn),
6661 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
6662 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
6664 tree fndecl = BV_FN (fn);
6666 if (DECL_THUNK_P (fndecl))
6667 /* A thunk. We should never be calling this entry directly
6668 from this vtable -- we'd use the entry for the non
6669 thunk base function. */
6670 DECL_VINDEX (fndecl) = NULL_TREE;
6671 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
6672 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
6676 finish_struct_bits (t);
6677 set_method_tm_attributes (t);
6679 /* Complete the rtl for any static member objects of the type we're
6681 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
6682 if (VAR_P (x) && TREE_STATIC (x)
6683 && TREE_TYPE (x) != error_mark_node
6684 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
6685 DECL_MODE (x) = TYPE_MODE (t);
6687 /* Done with FIELDS...now decide whether to sort these for
6688 faster lookups later.
6690 We use a small number because most searches fail (succeeding
6691 ultimately as the search bores through the inheritance
6692 hierarchy), and we want this failure to occur quickly. */
6694 insert_into_classtype_sorted_fields (TYPE_FIELDS (t), t, 8);
6696 /* Complain if one of the field types requires lower visibility. */
6697 constrain_class_visibility (t);
6699 /* Make the rtl for any new vtables we have created, and unmark
6700 the base types we marked. */
6703 /* Build the VTT for T. */
6706 /* This warning does not make sense for Java classes, since they
6707 cannot have destructors. */
6708 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor
6709 && TYPE_POLYMORPHIC_P (t) && accessible_nvdtor_p (t)
6710 && !CLASSTYPE_FINAL (t))
6711 warning (OPT_Wnon_virtual_dtor,
6712 "%q#T has virtual functions and accessible"
6713 " non-virtual destructor", t);
6717 if (warn_overloaded_virtual)
6720 /* Class layout, assignment of virtual table slots, etc., is now
6721 complete. Give the back end a chance to tweak the visibility of
6722 the class or perform any other required target modifications. */
6723 targetm.cxx.adjust_class_at_definition (t);
6725 maybe_suppress_debug_info (t);
6727 if (flag_vtable_verify)
6728 vtv_save_class_info (t);
6730 dump_class_hierarchy (t);
6732 /* Finish debugging output for this type. */
6733 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
6735 if (TYPE_TRANSPARENT_AGGR (t))
6737 tree field = first_field (t);
6738 if (field == NULL_TREE || error_operand_p (field))
6740 error ("type transparent %q#T does not have any fields", t);
6741 TYPE_TRANSPARENT_AGGR (t) = 0;
6743 else if (DECL_ARTIFICIAL (field))
6745 if (DECL_FIELD_IS_BASE (field))
6746 error ("type transparent class %qT has base classes", t);
6749 gcc_checking_assert (DECL_VIRTUAL_P (field));
6750 error ("type transparent class %qT has virtual functions", t);
6752 TYPE_TRANSPARENT_AGGR (t) = 0;
6754 else if (TYPE_MODE (t) != DECL_MODE (field))
6756 error ("type transparent %q#T cannot be made transparent because "
6757 "the type of the first field has a different ABI from the "
6758 "class overall", t);
6759 TYPE_TRANSPARENT_AGGR (t) = 0;
6764 /* Insert FIELDS into T for the sorted case if the FIELDS count is
6765 equal to THRESHOLD or greater than THRESHOLD. */
6768 insert_into_classtype_sorted_fields (tree fields, tree t, int threshold)
6770 int n_fields = count_fields (fields);
6771 if (n_fields >= threshold)
6773 struct sorted_fields_type *field_vec = sorted_fields_type_new (n_fields);
6774 add_fields_to_record_type (fields, field_vec, 0);
6775 qsort (field_vec->elts, n_fields, sizeof (tree), field_decl_cmp);
6776 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
6780 /* Insert lately defined enum ENUMTYPE into T for the sorted case. */
6783 insert_late_enum_def_into_classtype_sorted_fields (tree enumtype, tree t)
6785 struct sorted_fields_type *sorted_fields = CLASSTYPE_SORTED_FIELDS (t);
6790 = list_length (TYPE_VALUES (enumtype)) + sorted_fields->len;
6791 struct sorted_fields_type *field_vec = sorted_fields_type_new (n_fields);
6793 for (i = 0; i < sorted_fields->len; ++i)
6794 field_vec->elts[i] = sorted_fields->elts[i];
6796 add_enum_fields_to_record_type (enumtype, field_vec,
6797 sorted_fields->len);
6798 qsort (field_vec->elts, n_fields, sizeof (tree), field_decl_cmp);
6799 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
6803 /* When T was built up, the member declarations were added in reverse
6804 order. Rearrange them to declaration order. */
6807 unreverse_member_declarations (tree t)
6813 /* The following lists are all in reverse order. Put them in
6814 declaration order now. */
6815 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
6816 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
6818 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
6819 reverse order, so we can't just use nreverse. */
6821 for (x = TYPE_FIELDS (t);
6822 x && TREE_CODE (x) != TYPE_DECL;
6825 next = DECL_CHAIN (x);
6826 DECL_CHAIN (x) = prev;
6831 DECL_CHAIN (TYPE_FIELDS (t)) = x;
6833 TYPE_FIELDS (t) = prev;
6838 finish_struct (tree t, tree attributes)
6840 location_t saved_loc = input_location;
6842 /* Now that we've got all the field declarations, reverse everything
6844 unreverse_member_declarations (t);
6846 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
6847 fixup_attribute_variants (t);
6849 /* Nadger the current location so that diagnostics point to the start of
6850 the struct, not the end. */
6851 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
6853 if (processing_template_decl)
6857 finish_struct_methods (t);
6858 TYPE_SIZE (t) = bitsize_zero_node;
6859 TYPE_SIZE_UNIT (t) = size_zero_node;
6861 /* We need to emit an error message if this type was used as a parameter
6862 and it is an abstract type, even if it is a template. We construct
6863 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
6864 account and we call complete_vars with this type, which will check
6865 the PARM_DECLS. Note that while the type is being defined,
6866 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
6867 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
6868 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
6869 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
6870 if (DECL_PURE_VIRTUAL_P (x))
6871 vec_safe_push (CLASSTYPE_PURE_VIRTUALS (t), x);
6873 /* We need to add the target functions to the CLASSTYPE_METHOD_VEC if
6874 an enclosing scope is a template class, so that this function be
6875 found by lookup_fnfields_1 when the using declaration is not
6876 instantiated yet. */
6877 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
6878 if (TREE_CODE (x) == USING_DECL)
6880 tree fn = strip_using_decl (x);
6881 if (is_overloaded_fn (fn))
6882 for (; fn; fn = OVL_NEXT (fn))
6883 add_method (t, OVL_CURRENT (fn), x);
6886 /* Remember current #pragma pack value. */
6887 TYPE_PRECISION (t) = maximum_field_alignment;
6889 /* Fix up any variants we've already built. */
6890 for (x = TYPE_NEXT_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
6892 TYPE_SIZE (x) = TYPE_SIZE (t);
6893 TYPE_SIZE_UNIT (x) = TYPE_SIZE_UNIT (t);
6894 TYPE_FIELDS (x) = TYPE_FIELDS (t);
6895 TYPE_METHODS (x) = TYPE_METHODS (t);
6899 finish_struct_1 (t);
6901 if (is_std_init_list (t))
6903 /* People keep complaining that the compiler crashes on an invalid
6904 definition of initializer_list, so I guess we should explicitly
6905 reject it. What the compiler internals care about is that it's a
6906 template and has a pointer field followed by an integer field. */
6908 if (processing_template_decl)
6910 tree f = next_initializable_field (TYPE_FIELDS (t));
6911 if (f && TREE_CODE (TREE_TYPE (f)) == POINTER_TYPE)
6913 f = next_initializable_field (DECL_CHAIN (f));
6914 if (f && same_type_p (TREE_TYPE (f), size_type_node))
6919 fatal_error (input_location,
6920 "definition of std::initializer_list does not match "
6921 "#include <initializer_list>");
6924 input_location = saved_loc;
6926 TYPE_BEING_DEFINED (t) = 0;
6928 if (current_class_type)
6931 error ("trying to finish struct, but kicked out due to previous parse errors");
6933 if (processing_template_decl && at_function_scope_p ()
6934 /* Lambdas are defined by the LAMBDA_EXPR. */
6935 && !LAMBDA_TYPE_P (t))
6936 add_stmt (build_min (TAG_DEFN, t));
6941 /* Hash table to avoid endless recursion when handling references. */
6942 static hash_table<pointer_hash<tree_node> > *fixed_type_or_null_ref_ht;
6944 /* Return the dynamic type of INSTANCE, if known.
6945 Used to determine whether the virtual function table is needed
6948 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6949 of our knowledge of its type. *NONNULL should be initialized
6950 before this function is called. */
6953 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
6955 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
6957 switch (TREE_CODE (instance))
6960 if (POINTER_TYPE_P (TREE_TYPE (instance)))
6963 return RECUR (TREE_OPERAND (instance, 0));
6966 /* This is a call to a constructor, hence it's never zero. */
6967 if (TREE_HAS_CONSTRUCTOR (instance))
6971 return TREE_TYPE (instance);
6976 /* This is a call to a constructor, hence it's never zero. */
6977 if (TREE_HAS_CONSTRUCTOR (instance))
6981 return TREE_TYPE (instance);
6983 return RECUR (TREE_OPERAND (instance, 0));
6985 case POINTER_PLUS_EXPR:
6988 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
6989 return RECUR (TREE_OPERAND (instance, 0));
6990 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
6991 /* Propagate nonnull. */
6992 return RECUR (TREE_OPERAND (instance, 0));
6997 return RECUR (TREE_OPERAND (instance, 0));
7000 instance = TREE_OPERAND (instance, 0);
7003 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
7004 with a real object -- given &p->f, p can still be null. */
7005 tree t = get_base_address (instance);
7006 /* ??? Probably should check DECL_WEAK here. */
7007 if (t && DECL_P (t))
7010 return RECUR (instance);
7013 /* If this component is really a base class reference, then the field
7014 itself isn't definitive. */
7015 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
7016 return RECUR (TREE_OPERAND (instance, 0));
7017 return RECUR (TREE_OPERAND (instance, 1));
7021 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
7022 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
7026 return TREE_TYPE (TREE_TYPE (instance));
7028 /* fall through... */
7032 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
7036 return TREE_TYPE (instance);
7038 else if (instance == current_class_ptr)
7043 /* if we're in a ctor or dtor, we know our type. If
7044 current_class_ptr is set but we aren't in a function, we're in
7045 an NSDMI (and therefore a constructor). */
7046 if (current_scope () != current_function_decl
7047 || (DECL_LANG_SPECIFIC (current_function_decl)
7048 && (DECL_CONSTRUCTOR_P (current_function_decl)
7049 || DECL_DESTRUCTOR_P (current_function_decl))))
7053 return TREE_TYPE (TREE_TYPE (instance));
7056 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
7058 /* We only need one hash table because it is always left empty. */
7059 if (!fixed_type_or_null_ref_ht)
7060 fixed_type_or_null_ref_ht
7061 = new hash_table<pointer_hash<tree_node> > (37);
7063 /* Reference variables should be references to objects. */
7067 /* Enter the INSTANCE in a table to prevent recursion; a
7068 variable's initializer may refer to the variable
7070 if (VAR_P (instance)
7071 && DECL_INITIAL (instance)
7072 && !type_dependent_expression_p_push (DECL_INITIAL (instance))
7073 && !fixed_type_or_null_ref_ht->find (instance))
7078 slot = fixed_type_or_null_ref_ht->find_slot (instance, INSERT);
7080 type = RECUR (DECL_INITIAL (instance));
7081 fixed_type_or_null_ref_ht->remove_elt (instance);
7094 /* Return nonzero if the dynamic type of INSTANCE is known, and
7095 equivalent to the static type. We also handle the case where
7096 INSTANCE is really a pointer. Return negative if this is a
7097 ctor/dtor. There the dynamic type is known, but this might not be
7098 the most derived base of the original object, and hence virtual
7099 bases may not be laid out according to this type.
7101 Used to determine whether the virtual function table is needed
7104 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
7105 of our knowledge of its type. *NONNULL should be initialized
7106 before this function is called. */
7109 resolves_to_fixed_type_p (tree instance, int* nonnull)
7111 tree t = TREE_TYPE (instance);
7115 /* processing_template_decl can be false in a template if we're in
7116 instantiate_non_dependent_expr, but we still want to suppress
7118 if (in_template_function ())
7120 /* In a template we only care about the type of the result. */
7126 fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
7127 if (fixed == NULL_TREE)
7129 if (POINTER_TYPE_P (t))
7131 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
7133 return cdtorp ? -1 : 1;
7138 init_class_processing (void)
7140 current_class_depth = 0;
7141 current_class_stack_size = 10;
7143 = XNEWVEC (struct class_stack_node, current_class_stack_size);
7144 vec_alloc (local_classes, 8);
7145 sizeof_biggest_empty_class = size_zero_node;
7147 ridpointers[(int) RID_PUBLIC] = access_public_node;
7148 ridpointers[(int) RID_PRIVATE] = access_private_node;
7149 ridpointers[(int) RID_PROTECTED] = access_protected_node;
7152 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
7155 restore_class_cache (void)
7159 /* We are re-entering the same class we just left, so we don't
7160 have to search the whole inheritance matrix to find all the
7161 decls to bind again. Instead, we install the cached
7162 class_shadowed list and walk through it binding names. */
7163 push_binding_level (previous_class_level);
7164 class_binding_level = previous_class_level;
7165 /* Restore IDENTIFIER_TYPE_VALUE. */
7166 for (type = class_binding_level->type_shadowed;
7168 type = TREE_CHAIN (type))
7169 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
7172 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
7173 appropriate for TYPE.
7175 So that we may avoid calls to lookup_name, we cache the _TYPE
7176 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
7178 For multiple inheritance, we perform a two-pass depth-first search
7179 of the type lattice. */
7182 pushclass (tree type)
7184 class_stack_node_t csn;
7186 type = TYPE_MAIN_VARIANT (type);
7188 /* Make sure there is enough room for the new entry on the stack. */
7189 if (current_class_depth + 1 >= current_class_stack_size)
7191 current_class_stack_size *= 2;
7193 = XRESIZEVEC (struct class_stack_node, current_class_stack,
7194 current_class_stack_size);
7197 /* Insert a new entry on the class stack. */
7198 csn = current_class_stack + current_class_depth;
7199 csn->name = current_class_name;
7200 csn->type = current_class_type;
7201 csn->access = current_access_specifier;
7202 csn->names_used = 0;
7204 current_class_depth++;
7206 /* Now set up the new type. */
7207 current_class_name = TYPE_NAME (type);
7208 if (TREE_CODE (current_class_name) == TYPE_DECL)
7209 current_class_name = DECL_NAME (current_class_name);
7210 current_class_type = type;
7212 /* By default, things in classes are private, while things in
7213 structures or unions are public. */
7214 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
7215 ? access_private_node
7216 : access_public_node);
7218 if (previous_class_level
7219 && type != previous_class_level->this_entity
7220 && current_class_depth == 1)
7222 /* Forcibly remove any old class remnants. */
7223 invalidate_class_lookup_cache ();
7226 if (!previous_class_level
7227 || type != previous_class_level->this_entity
7228 || current_class_depth > 1)
7231 restore_class_cache ();
7234 /* When we exit a toplevel class scope, we save its binding level so
7235 that we can restore it quickly. Here, we've entered some other
7236 class, so we must invalidate our cache. */
7239 invalidate_class_lookup_cache (void)
7241 previous_class_level = NULL;
7244 /* Get out of the current class scope. If we were in a class scope
7245 previously, that is the one popped to. */
7252 current_class_depth--;
7253 current_class_name = current_class_stack[current_class_depth].name;
7254 current_class_type = current_class_stack[current_class_depth].type;
7255 current_access_specifier = current_class_stack[current_class_depth].access;
7256 if (current_class_stack[current_class_depth].names_used)
7257 splay_tree_delete (current_class_stack[current_class_depth].names_used);
7260 /* Mark the top of the class stack as hidden. */
7263 push_class_stack (void)
7265 if (current_class_depth)
7266 ++current_class_stack[current_class_depth - 1].hidden;
7269 /* Mark the top of the class stack as un-hidden. */
7272 pop_class_stack (void)
7274 if (current_class_depth)
7275 --current_class_stack[current_class_depth - 1].hidden;
7278 /* Returns 1 if the class type currently being defined is either T or
7279 a nested type of T. */
7282 currently_open_class (tree t)
7286 if (!CLASS_TYPE_P (t))
7289 t = TYPE_MAIN_VARIANT (t);
7291 /* We start looking from 1 because entry 0 is from global scope,
7293 for (i = current_class_depth; i > 0; --i)
7296 if (i == current_class_depth)
7297 c = current_class_type;
7300 if (current_class_stack[i].hidden)
7302 c = current_class_stack[i].type;
7306 if (same_type_p (c, t))
7312 /* If either current_class_type or one of its enclosing classes are derived
7313 from T, return the appropriate type. Used to determine how we found
7314 something via unqualified lookup. */
7317 currently_open_derived_class (tree t)
7321 /* The bases of a dependent type are unknown. */
7322 if (dependent_type_p (t))
7325 if (!current_class_type)
7328 if (DERIVED_FROM_P (t, current_class_type))
7329 return current_class_type;
7331 for (i = current_class_depth - 1; i > 0; --i)
7333 if (current_class_stack[i].hidden)
7335 if (DERIVED_FROM_P (t, current_class_stack[i].type))
7336 return current_class_stack[i].type;
7342 /* Return the outermost enclosing class type that is still open, or
7346 outermost_open_class (void)
7348 if (!current_class_type)
7351 if (TYPE_BEING_DEFINED (current_class_type))
7352 r = current_class_type;
7353 for (int i = current_class_depth - 1; i > 0; --i)
7355 if (current_class_stack[i].hidden)
7357 tree t = current_class_stack[i].type;
7358 if (!TYPE_BEING_DEFINED (t))
7365 /* Returns the innermost class type which is not a lambda closure type. */
7368 current_nonlambda_class_type (void)
7372 /* We start looking from 1 because entry 0 is from global scope,
7374 for (i = current_class_depth; i > 0; --i)
7377 if (i == current_class_depth)
7378 c = current_class_type;
7381 if (current_class_stack[i].hidden)
7383 c = current_class_stack[i].type;
7387 if (!LAMBDA_TYPE_P (c))
7393 /* When entering a class scope, all enclosing class scopes' names with
7394 static meaning (static variables, static functions, types and
7395 enumerators) have to be visible. This recursive function calls
7396 pushclass for all enclosing class contexts until global or a local
7397 scope is reached. TYPE is the enclosed class. */
7400 push_nested_class (tree type)
7402 /* A namespace might be passed in error cases, like A::B:C. */
7403 if (type == NULL_TREE
7404 || !CLASS_TYPE_P (type))
7407 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
7412 /* Undoes a push_nested_class call. */
7415 pop_nested_class (void)
7417 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
7420 if (context && CLASS_TYPE_P (context))
7421 pop_nested_class ();
7424 /* Returns the number of extern "LANG" blocks we are nested within. */
7427 current_lang_depth (void)
7429 return vec_safe_length (current_lang_base);
7432 /* Set global variables CURRENT_LANG_NAME to appropriate value
7433 so that behavior of name-mangling machinery is correct. */
7436 push_lang_context (tree name)
7438 vec_safe_push (current_lang_base, current_lang_name);
7440 if (name == lang_name_cplusplus)
7442 current_lang_name = name;
7444 else if (name == lang_name_java)
7446 current_lang_name = name;
7447 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
7448 (See record_builtin_java_type in decl.c.) However, that causes
7449 incorrect debug entries if these types are actually used.
7450 So we re-enable debug output after extern "Java". */
7451 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
7452 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
7453 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
7454 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
7455 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
7456 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
7457 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
7458 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
7460 else if (name == lang_name_c)
7462 current_lang_name = name;
7465 error ("language string %<\"%E\"%> not recognized", name);
7468 /* Get out of the current language scope. */
7471 pop_lang_context (void)
7473 current_lang_name = current_lang_base->pop ();
7476 /* Type instantiation routines. */
7478 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
7479 matches the TARGET_TYPE. If there is no satisfactory match, return
7480 error_mark_node, and issue an error & warning messages under
7481 control of FLAGS. Permit pointers to member function if FLAGS
7482 permits. If TEMPLATE_ONLY, the name of the overloaded function was
7483 a template-id, and EXPLICIT_TARGS are the explicitly provided
7486 If OVERLOAD is for one or more member functions, then ACCESS_PATH
7487 is the base path used to reference those member functions. If
7488 the address is resolved to a member function, access checks will be
7489 performed and errors issued if appropriate. */
7492 resolve_address_of_overloaded_function (tree target_type,
7494 tsubst_flags_t flags,
7496 tree explicit_targs,
7499 /* Here's what the standard says:
7503 If the name is a function template, template argument deduction
7504 is done, and if the argument deduction succeeds, the deduced
7505 arguments are used to generate a single template function, which
7506 is added to the set of overloaded functions considered.
7508 Non-member functions and static member functions match targets of
7509 type "pointer-to-function" or "reference-to-function." Nonstatic
7510 member functions match targets of type "pointer-to-member
7511 function;" the function type of the pointer to member is used to
7512 select the member function from the set of overloaded member
7513 functions. If a nonstatic member function is selected, the
7514 reference to the overloaded function name is required to have the
7515 form of a pointer to member as described in 5.3.1.
7517 If more than one function is selected, any template functions in
7518 the set are eliminated if the set also contains a non-template
7519 function, and any given template function is eliminated if the
7520 set contains a second template function that is more specialized
7521 than the first according to the partial ordering rules 14.5.5.2.
7522 After such eliminations, if any, there shall remain exactly one
7523 selected function. */
7526 /* We store the matches in a TREE_LIST rooted here. The functions
7527 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
7528 interoperability with most_specialized_instantiation. */
7529 tree matches = NULL_TREE;
7531 tree target_fn_type;
7533 /* By the time we get here, we should be seeing only real
7534 pointer-to-member types, not the internal POINTER_TYPE to
7535 METHOD_TYPE representation. */
7536 gcc_assert (!TYPE_PTR_P (target_type)
7537 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
7539 gcc_assert (is_overloaded_fn (overload));
7541 /* Check that the TARGET_TYPE is reasonable. */
7542 if (TYPE_PTRFN_P (target_type)
7543 || TYPE_REFFN_P (target_type))
7545 else if (TYPE_PTRMEMFUNC_P (target_type))
7546 /* This is OK, too. */
7548 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
7549 /* This is OK, too. This comes from a conversion to reference
7551 target_type = build_reference_type (target_type);
7554 if (flags & tf_error)
7555 error ("cannot resolve overloaded function %qD based on"
7556 " conversion to type %qT",
7557 DECL_NAME (OVL_FUNCTION (overload)), target_type);
7558 return error_mark_node;
7561 /* Non-member functions and static member functions match targets of type
7562 "pointer-to-function" or "reference-to-function." Nonstatic member
7563 functions match targets of type "pointer-to-member-function;" the
7564 function type of the pointer to member is used to select the member
7565 function from the set of overloaded member functions.
7567 So figure out the FUNCTION_TYPE that we want to match against. */
7568 target_fn_type = static_fn_type (target_type);
7570 /* If we can find a non-template function that matches, we can just
7571 use it. There's no point in generating template instantiations
7572 if we're just going to throw them out anyhow. But, of course, we
7573 can only do this when we don't *need* a template function. */
7578 for (fns = overload; fns; fns = OVL_NEXT (fns))
7580 tree fn = OVL_CURRENT (fns);
7582 if (TREE_CODE (fn) == TEMPLATE_DECL)
7583 /* We're not looking for templates just yet. */
7586 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
7588 /* We're looking for a non-static member, and this isn't
7589 one, or vice versa. */
7592 /* Ignore functions which haven't been explicitly
7594 if (DECL_ANTICIPATED (fn))
7597 /* See if there's a match. */
7598 if (same_type_p (target_fn_type, static_fn_type (fn)))
7599 matches = tree_cons (fn, NULL_TREE, matches);
7603 /* Now, if we've already got a match (or matches), there's no need
7604 to proceed to the template functions. But, if we don't have a
7605 match we need to look at them, too. */
7608 tree target_arg_types;
7609 tree target_ret_type;
7612 unsigned int nargs, ia;
7615 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
7616 target_ret_type = TREE_TYPE (target_fn_type);
7618 nargs = list_length (target_arg_types);
7619 args = XALLOCAVEC (tree, nargs);
7620 for (arg = target_arg_types, ia = 0;
7621 arg != NULL_TREE && arg != void_list_node;
7622 arg = TREE_CHAIN (arg), ++ia)
7623 args[ia] = TREE_VALUE (arg);
7626 for (fns = overload; fns; fns = OVL_NEXT (fns))
7628 tree fn = OVL_CURRENT (fns);
7632 if (TREE_CODE (fn) != TEMPLATE_DECL)
7633 /* We're only looking for templates. */
7636 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
7638 /* We're not looking for a non-static member, and this is
7639 one, or vice versa. */
7642 tree ret = target_ret_type;
7644 /* If the template has a deduced return type, don't expose it to
7645 template argument deduction. */
7646 if (undeduced_auto_decl (fn))
7649 /* Try to do argument deduction. */
7650 targs = make_tree_vec (DECL_NTPARMS (fn));
7651 instantiation = fn_type_unification (fn, explicit_targs, targs, args,
7653 DEDUCE_EXACT, LOOKUP_NORMAL,
7655 if (instantiation == error_mark_node)
7656 /* Instantiation failed. */
7659 /* And now force instantiation to do return type deduction. */
7660 if (undeduced_auto_decl (instantiation))
7663 instantiate_decl (instantiation, /*defer*/false, /*class*/false);
7666 require_deduced_type (instantiation);
7669 /* See if there's a match. */
7670 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
7671 matches = tree_cons (instantiation, fn, matches);
7674 /* Now, remove all but the most specialized of the matches. */
7677 tree match = most_specialized_instantiation (matches);
7679 if (match != error_mark_node)
7680 matches = tree_cons (TREE_PURPOSE (match),
7686 /* Now we should have exactly one function in MATCHES. */
7687 if (matches == NULL_TREE)
7689 /* There were *no* matches. */
7690 if (flags & tf_error)
7692 error ("no matches converting function %qD to type %q#T",
7693 DECL_NAME (OVL_CURRENT (overload)),
7696 print_candidates (overload);
7698 return error_mark_node;
7700 else if (TREE_CHAIN (matches))
7702 /* There were too many matches. First check if they're all
7703 the same function. */
7704 tree match = NULL_TREE;
7706 fn = TREE_PURPOSE (matches);
7708 /* For multi-versioned functions, more than one match is just fine and
7709 decls_match will return false as they are different. */
7710 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
7711 if (!decls_match (fn, TREE_PURPOSE (match))
7712 && !targetm.target_option.function_versions
7713 (fn, TREE_PURPOSE (match)))
7718 if (flags & tf_error)
7720 error ("converting overloaded function %qD to type %q#T is ambiguous",
7721 DECL_NAME (OVL_FUNCTION (overload)),
7724 /* Since print_candidates expects the functions in the
7725 TREE_VALUE slot, we flip them here. */
7726 for (match = matches; match; match = TREE_CHAIN (match))
7727 TREE_VALUE (match) = TREE_PURPOSE (match);
7729 print_candidates (matches);
7732 return error_mark_node;
7736 /* Good, exactly one match. Now, convert it to the correct type. */
7737 fn = TREE_PURPOSE (matches);
7739 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
7740 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
7742 static int explained;
7744 if (!(flags & tf_error))
7745 return error_mark_node;
7747 permerror (input_location, "assuming pointer to member %qD", fn);
7750 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
7755 /* If a pointer to a function that is multi-versioned is requested, the
7756 pointer to the dispatcher function is returned instead. This works
7757 well because indirectly calling the function will dispatch the right
7758 function version at run-time. */
7759 if (DECL_FUNCTION_VERSIONED (fn))
7761 fn = get_function_version_dispatcher (fn);
7763 return error_mark_node;
7764 /* Mark all the versions corresponding to the dispatcher as used. */
7765 if (!(flags & tf_conv))
7766 mark_versions_used (fn);
7769 /* If we're doing overload resolution purely for the purpose of
7770 determining conversion sequences, we should not consider the
7771 function used. If this conversion sequence is selected, the
7772 function will be marked as used at this point. */
7773 if (!(flags & tf_conv))
7775 /* Make =delete work with SFINAE. */
7776 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
7777 return error_mark_node;
7782 /* We could not check access to member functions when this
7783 expression was originally created since we did not know at that
7784 time to which function the expression referred. */
7785 if (DECL_FUNCTION_MEMBER_P (fn))
7787 gcc_assert (access_path);
7788 perform_or_defer_access_check (access_path, fn, fn, flags);
7791 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
7792 return cp_build_addr_expr (fn, flags);
7795 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
7796 will mark the function as addressed, but here we must do it
7798 cxx_mark_addressable (fn);
7804 /* This function will instantiate the type of the expression given in
7805 RHS to match the type of LHSTYPE. If errors exist, then return
7806 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
7807 we complain on errors. If we are not complaining, never modify rhs,
7808 as overload resolution wants to try many possible instantiations, in
7809 the hope that at least one will work.
7811 For non-recursive calls, LHSTYPE should be a function, pointer to
7812 function, or a pointer to member function. */
7815 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
7817 tsubst_flags_t flags_in = flags;
7818 tree access_path = NULL_TREE;
7820 flags &= ~tf_ptrmem_ok;
7822 if (lhstype == unknown_type_node)
7824 if (flags & tf_error)
7825 error ("not enough type information");
7826 return error_mark_node;
7829 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
7831 tree fntype = non_reference (lhstype);
7832 if (same_type_p (fntype, TREE_TYPE (rhs)))
7834 if (flag_ms_extensions
7835 && TYPE_PTRMEMFUNC_P (fntype)
7836 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
7837 /* Microsoft allows `A::f' to be resolved to a
7838 pointer-to-member. */
7842 if (flags & tf_error)
7843 error ("cannot convert %qE from type %qT to type %qT",
7844 rhs, TREE_TYPE (rhs), fntype);
7845 return error_mark_node;
7849 if (BASELINK_P (rhs))
7851 access_path = BASELINK_ACCESS_BINFO (rhs);
7852 rhs = BASELINK_FUNCTIONS (rhs);
7855 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
7856 deduce any type information. */
7857 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
7859 if (flags & tf_error)
7860 error ("not enough type information");
7861 return error_mark_node;
7864 /* There only a few kinds of expressions that may have a type
7865 dependent on overload resolution. */
7866 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
7867 || TREE_CODE (rhs) == COMPONENT_REF
7868 || is_overloaded_fn (rhs)
7869 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
7871 /* This should really only be used when attempting to distinguish
7872 what sort of a pointer to function we have. For now, any
7873 arithmetic operation which is not supported on pointers
7874 is rejected as an error. */
7876 switch (TREE_CODE (rhs))
7880 tree member = TREE_OPERAND (rhs, 1);
7882 member = instantiate_type (lhstype, member, flags);
7883 if (member != error_mark_node
7884 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
7885 /* Do not lose object's side effects. */
7886 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
7887 TREE_OPERAND (rhs, 0), member);
7892 rhs = TREE_OPERAND (rhs, 1);
7893 if (BASELINK_P (rhs))
7894 return instantiate_type (lhstype, rhs, flags_in);
7896 /* This can happen if we are forming a pointer-to-member for a
7898 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
7902 case TEMPLATE_ID_EXPR:
7904 tree fns = TREE_OPERAND (rhs, 0);
7905 tree args = TREE_OPERAND (rhs, 1);
7908 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
7909 /*template_only=*/true,
7916 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
7917 /*template_only=*/false,
7918 /*explicit_targs=*/NULL_TREE,
7923 if (PTRMEM_OK_P (rhs))
7924 flags |= tf_ptrmem_ok;
7926 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
7930 return error_mark_node;
7935 return error_mark_node;
7938 /* Return the name of the virtual function pointer field
7939 (as an IDENTIFIER_NODE) for the given TYPE. Note that
7940 this may have to look back through base types to find the
7941 ultimate field name. (For single inheritance, these could
7942 all be the same name. Who knows for multiple inheritance). */
7945 get_vfield_name (tree type)
7947 tree binfo, base_binfo;
7950 for (binfo = TYPE_BINFO (type);
7951 BINFO_N_BASE_BINFOS (binfo);
7954 base_binfo = BINFO_BASE_BINFO (binfo, 0);
7956 if (BINFO_VIRTUAL_P (base_binfo)
7957 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
7961 type = BINFO_TYPE (binfo);
7962 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
7963 + TYPE_NAME_LENGTH (type) + 2);
7964 sprintf (buf, VFIELD_NAME_FORMAT,
7965 IDENTIFIER_POINTER (constructor_name (type)));
7966 return get_identifier (buf);
7970 print_class_statistics (void)
7972 if (! GATHER_STATISTICS)
7975 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
7976 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
7979 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
7980 n_vtables, n_vtable_searches);
7981 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
7982 n_vtable_entries, n_vtable_elems);
7986 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
7987 according to [class]:
7988 The class-name is also inserted
7989 into the scope of the class itself. For purposes of access checking,
7990 the inserted class name is treated as if it were a public member name. */
7993 build_self_reference (void)
7995 tree name = constructor_name (current_class_type);
7996 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
7999 DECL_NONLOCAL (value) = 1;
8000 DECL_CONTEXT (value) = current_class_type;
8001 DECL_ARTIFICIAL (value) = 1;
8002 SET_DECL_SELF_REFERENCE_P (value);
8003 set_underlying_type (value);
8005 if (processing_template_decl)
8006 value = push_template_decl (value);
8008 saved_cas = current_access_specifier;
8009 current_access_specifier = access_public_node;
8010 finish_member_declaration (value);
8011 current_access_specifier = saved_cas;
8014 /* Returns 1 if TYPE contains only padding bytes. */
8017 is_empty_class (tree type)
8019 if (type == error_mark_node)
8022 if (! CLASS_TYPE_P (type))
8025 return CLASSTYPE_EMPTY_P (type);
8028 /* Returns true if TYPE contains no actual data, just various
8029 possible combinations of empty classes and possibly a vptr. */
8032 is_really_empty_class (tree type)
8034 if (CLASS_TYPE_P (type))
8041 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
8042 out, but we'd like to be able to check this before then. */
8043 if (COMPLETE_TYPE_P (type) && is_empty_class (type))
8046 for (binfo = TYPE_BINFO (type), i = 0;
8047 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8048 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
8050 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
8051 if (TREE_CODE (field) == FIELD_DECL
8052 && !DECL_ARTIFICIAL (field)
8053 && !is_really_empty_class (TREE_TYPE (field)))
8057 else if (TREE_CODE (type) == ARRAY_TYPE)
8058 return is_really_empty_class (TREE_TYPE (type));
8062 /* Note that NAME was looked up while the current class was being
8063 defined and that the result of that lookup was DECL. */
8066 maybe_note_name_used_in_class (tree name, tree decl)
8068 splay_tree names_used;
8070 /* If we're not defining a class, there's nothing to do. */
8071 if (!(innermost_scope_kind() == sk_class
8072 && TYPE_BEING_DEFINED (current_class_type)
8073 && !LAMBDA_TYPE_P (current_class_type)))
8076 /* If there's already a binding for this NAME, then we don't have
8077 anything to worry about. */
8078 if (lookup_member (current_class_type, name,
8079 /*protect=*/0, /*want_type=*/false, tf_warning_or_error))
8082 if (!current_class_stack[current_class_depth - 1].names_used)
8083 current_class_stack[current_class_depth - 1].names_used
8084 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
8085 names_used = current_class_stack[current_class_depth - 1].names_used;
8087 splay_tree_insert (names_used,
8088 (splay_tree_key) name,
8089 (splay_tree_value) decl);
8092 /* Note that NAME was declared (as DECL) in the current class. Check
8093 to see that the declaration is valid. */
8096 note_name_declared_in_class (tree name, tree decl)
8098 splay_tree names_used;
8101 /* Look to see if we ever used this name. */
8103 = current_class_stack[current_class_depth - 1].names_used;
8106 /* The C language allows members to be declared with a type of the same
8107 name, and the C++ standard says this diagnostic is not required. So
8108 allow it in extern "C" blocks unless predantic is specified.
8109 Allow it in all cases if -ms-extensions is specified. */
8110 if ((!pedantic && current_lang_name == lang_name_c)
8111 || flag_ms_extensions)
8113 n = splay_tree_lookup (names_used, (splay_tree_key) name);
8116 /* [basic.scope.class]
8118 A name N used in a class S shall refer to the same declaration
8119 in its context and when re-evaluated in the completed scope of
8121 permerror (input_location, "declaration of %q#D", decl);
8122 permerror (input_location, "changes meaning of %qD from %q+#D",
8123 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
8127 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
8128 Secondary vtables are merged with primary vtables; this function
8129 will return the VAR_DECL for the primary vtable. */
8132 get_vtbl_decl_for_binfo (tree binfo)
8136 decl = BINFO_VTABLE (binfo);
8137 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
8139 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
8140 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
8143 gcc_assert (VAR_P (decl));
8148 /* Returns the binfo for the primary base of BINFO. If the resulting
8149 BINFO is a virtual base, and it is inherited elsewhere in the
8150 hierarchy, then the returned binfo might not be the primary base of
8151 BINFO in the complete object. Check BINFO_PRIMARY_P or
8152 BINFO_LOST_PRIMARY_P to be sure. */
8155 get_primary_binfo (tree binfo)
8159 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
8163 return copied_binfo (primary_base, binfo);
8166 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
8169 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
8172 fprintf (stream, "%*s", indent, "");
8176 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
8177 INDENT should be zero when called from the top level; it is
8178 incremented recursively. IGO indicates the next expected BINFO in
8179 inheritance graph ordering. */
8182 dump_class_hierarchy_r (FILE *stream,
8192 indented = maybe_indent_hierarchy (stream, indent, 0);
8193 fprintf (stream, "%s (0x" HOST_WIDE_INT_PRINT_HEX ") ",
8194 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
8195 (HOST_WIDE_INT) (uintptr_t) binfo);
8198 fprintf (stream, "alternative-path\n");
8201 igo = TREE_CHAIN (binfo);
8203 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
8204 tree_to_shwi (BINFO_OFFSET (binfo)));
8205 if (is_empty_class (BINFO_TYPE (binfo)))
8206 fprintf (stream, " empty");
8207 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
8208 fprintf (stream, " nearly-empty");
8209 if (BINFO_VIRTUAL_P (binfo))
8210 fprintf (stream, " virtual");
8211 fprintf (stream, "\n");
8214 if (BINFO_PRIMARY_P (binfo))
8216 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8217 fprintf (stream, " primary-for %s (0x" HOST_WIDE_INT_PRINT_HEX ")",
8218 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
8219 TFF_PLAIN_IDENTIFIER),
8220 (HOST_WIDE_INT) (uintptr_t) BINFO_INHERITANCE_CHAIN (binfo));
8222 if (BINFO_LOST_PRIMARY_P (binfo))
8224 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8225 fprintf (stream, " lost-primary");
8228 fprintf (stream, "\n");
8230 if (!(flags & TDF_SLIM))
8234 if (BINFO_SUBVTT_INDEX (binfo))
8236 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8237 fprintf (stream, " subvttidx=%s",
8238 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
8239 TFF_PLAIN_IDENTIFIER));
8241 if (BINFO_VPTR_INDEX (binfo))
8243 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8244 fprintf (stream, " vptridx=%s",
8245 expr_as_string (BINFO_VPTR_INDEX (binfo),
8246 TFF_PLAIN_IDENTIFIER));
8248 if (BINFO_VPTR_FIELD (binfo))
8250 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8251 fprintf (stream, " vbaseoffset=%s",
8252 expr_as_string (BINFO_VPTR_FIELD (binfo),
8253 TFF_PLAIN_IDENTIFIER));
8255 if (BINFO_VTABLE (binfo))
8257 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8258 fprintf (stream, " vptr=%s",
8259 expr_as_string (BINFO_VTABLE (binfo),
8260 TFF_PLAIN_IDENTIFIER));
8264 fprintf (stream, "\n");
8267 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
8268 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
8273 /* Dump the BINFO hierarchy for T. */
8276 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
8278 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
8279 fprintf (stream, " size=%lu align=%lu\n",
8280 (unsigned long)(tree_to_shwi (TYPE_SIZE (t)) / BITS_PER_UNIT),
8281 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
8282 fprintf (stream, " base size=%lu base align=%lu\n",
8283 (unsigned long)(tree_to_shwi (TYPE_SIZE (CLASSTYPE_AS_BASE (t)))
8285 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
8287 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
8288 fprintf (stream, "\n");
8291 /* Debug interface to hierarchy dumping. */
8294 debug_class (tree t)
8296 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
8300 dump_class_hierarchy (tree t)
8303 FILE *stream = get_dump_info (TDI_class, &flags);
8307 dump_class_hierarchy_1 (stream, flags, t);
8312 dump_array (FILE * stream, tree decl)
8315 unsigned HOST_WIDE_INT ix;
8317 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
8319 elt = (tree_to_shwi (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))))
8321 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
8322 fprintf (stream, " %s entries",
8323 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
8324 TFF_PLAIN_IDENTIFIER));
8325 fprintf (stream, "\n");
8327 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
8329 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
8330 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
8334 dump_vtable (tree t, tree binfo, tree vtable)
8337 FILE *stream = get_dump_info (TDI_class, &flags);
8342 if (!(flags & TDF_SLIM))
8344 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
8346 fprintf (stream, "%s for %s",
8347 ctor_vtbl_p ? "Construction vtable" : "Vtable",
8348 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
8351 if (!BINFO_VIRTUAL_P (binfo))
8352 fprintf (stream, " (0x" HOST_WIDE_INT_PRINT_HEX " instance)",
8353 (HOST_WIDE_INT) (uintptr_t) binfo);
8354 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
8356 fprintf (stream, "\n");
8357 dump_array (stream, vtable);
8358 fprintf (stream, "\n");
8363 dump_vtt (tree t, tree vtt)
8366 FILE *stream = get_dump_info (TDI_class, &flags);
8371 if (!(flags & TDF_SLIM))
8373 fprintf (stream, "VTT for %s\n",
8374 type_as_string (t, TFF_PLAIN_IDENTIFIER));
8375 dump_array (stream, vtt);
8376 fprintf (stream, "\n");
8380 /* Dump a function or thunk and its thunkees. */
8383 dump_thunk (FILE *stream, int indent, tree thunk)
8385 static const char spaces[] = " ";
8386 tree name = DECL_NAME (thunk);
8389 fprintf (stream, "%.*s%p %s %s", indent, spaces,
8391 !DECL_THUNK_P (thunk) ? "function"
8392 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
8393 name ? IDENTIFIER_POINTER (name) : "<unset>");
8394 if (DECL_THUNK_P (thunk))
8396 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
8397 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
8399 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
8400 if (!virtual_adjust)
8402 else if (DECL_THIS_THUNK_P (thunk))
8403 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
8404 tree_to_shwi (virtual_adjust));
8406 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
8407 tree_to_shwi (BINFO_VPTR_FIELD (virtual_adjust)),
8408 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
8409 if (THUNK_ALIAS (thunk))
8410 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
8412 fprintf (stream, "\n");
8413 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
8414 dump_thunk (stream, indent + 2, thunks);
8417 /* Dump the thunks for FN. */
8420 debug_thunks (tree fn)
8422 dump_thunk (stderr, 0, fn);
8425 /* Virtual function table initialization. */
8427 /* Create all the necessary vtables for T and its base classes. */
8430 finish_vtbls (tree t)
8433 vec<constructor_elt, va_gc> *v = NULL;
8434 tree vtable = BINFO_VTABLE (TYPE_BINFO (t));
8436 /* We lay out the primary and secondary vtables in one contiguous
8437 vtable. The primary vtable is first, followed by the non-virtual
8438 secondary vtables in inheritance graph order. */
8439 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t),
8442 /* Then come the virtual bases, also in inheritance graph order. */
8443 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
8445 if (!BINFO_VIRTUAL_P (vbase))
8447 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), vtable, t, &v);
8450 if (BINFO_VTABLE (TYPE_BINFO (t)))
8451 initialize_vtable (TYPE_BINFO (t), v);
8454 /* Initialize the vtable for BINFO with the INITS. */
8457 initialize_vtable (tree binfo, vec<constructor_elt, va_gc> *inits)
8461 layout_vtable_decl (binfo, vec_safe_length (inits));
8462 decl = get_vtbl_decl_for_binfo (binfo);
8463 initialize_artificial_var (decl, inits);
8464 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
8467 /* Build the VTT (virtual table table) for T.
8468 A class requires a VTT if it has virtual bases.
8471 1 - primary virtual pointer for complete object T
8472 2 - secondary VTTs for each direct non-virtual base of T which requires a
8474 3 - secondary virtual pointers for each direct or indirect base of T which
8475 has virtual bases or is reachable via a virtual path from T.
8476 4 - secondary VTTs for each direct or indirect virtual base of T.
8478 Secondary VTTs look like complete object VTTs without part 4. */
8486 vec<constructor_elt, va_gc> *inits;
8488 /* Build up the initializers for the VTT. */
8490 index = size_zero_node;
8491 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
8493 /* If we didn't need a VTT, we're done. */
8497 /* Figure out the type of the VTT. */
8498 type = build_array_of_n_type (const_ptr_type_node,
8501 /* Now, build the VTT object itself. */
8502 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
8503 initialize_artificial_var (vtt, inits);
8504 /* Add the VTT to the vtables list. */
8505 DECL_CHAIN (vtt) = DECL_CHAIN (CLASSTYPE_VTABLES (t));
8506 DECL_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
8511 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
8512 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
8513 and CHAIN the vtable pointer for this binfo after construction is
8514 complete. VALUE can also be another BINFO, in which case we recurse. */
8517 binfo_ctor_vtable (tree binfo)
8523 vt = BINFO_VTABLE (binfo);
8524 if (TREE_CODE (vt) == TREE_LIST)
8525 vt = TREE_VALUE (vt);
8526 if (TREE_CODE (vt) == TREE_BINFO)
8535 /* Data for secondary VTT initialization. */
8536 typedef struct secondary_vptr_vtt_init_data_s
8538 /* Is this the primary VTT? */
8541 /* Current index into the VTT. */
8544 /* Vector of initializers built up. */
8545 vec<constructor_elt, va_gc> *inits;
8547 /* The type being constructed by this secondary VTT. */
8548 tree type_being_constructed;
8549 } secondary_vptr_vtt_init_data;
8551 /* Recursively build the VTT-initializer for BINFO (which is in the
8552 hierarchy dominated by T). INITS points to the end of the initializer
8553 list to date. INDEX is the VTT index where the next element will be
8554 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
8555 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
8556 for virtual bases of T. When it is not so, we build the constructor
8557 vtables for the BINFO-in-T variant. */
8560 build_vtt_inits (tree binfo, tree t, vec<constructor_elt, va_gc> **inits,
8566 secondary_vptr_vtt_init_data data;
8567 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
8569 /* We only need VTTs for subobjects with virtual bases. */
8570 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
8573 /* We need to use a construction vtable if this is not the primary
8577 build_ctor_vtbl_group (binfo, t);
8579 /* Record the offset in the VTT where this sub-VTT can be found. */
8580 BINFO_SUBVTT_INDEX (binfo) = *index;
8583 /* Add the address of the primary vtable for the complete object. */
8584 init = binfo_ctor_vtable (binfo);
8585 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8588 gcc_assert (!BINFO_VPTR_INDEX (binfo));
8589 BINFO_VPTR_INDEX (binfo) = *index;
8591 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
8593 /* Recursively add the secondary VTTs for non-virtual bases. */
8594 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
8595 if (!BINFO_VIRTUAL_P (b))
8596 build_vtt_inits (b, t, inits, index);
8598 /* Add secondary virtual pointers for all subobjects of BINFO with
8599 either virtual bases or reachable along a virtual path, except
8600 subobjects that are non-virtual primary bases. */
8601 data.top_level_p = top_level_p;
8602 data.index = *index;
8603 data.inits = *inits;
8604 data.type_being_constructed = BINFO_TYPE (binfo);
8606 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
8608 *index = data.index;
8610 /* data.inits might have grown as we added secondary virtual pointers.
8611 Make sure our caller knows about the new vector. */
8612 *inits = data.inits;
8615 /* Add the secondary VTTs for virtual bases in inheritance graph
8617 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
8619 if (!BINFO_VIRTUAL_P (b))
8622 build_vtt_inits (b, t, inits, index);
8625 /* Remove the ctor vtables we created. */
8626 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
8629 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
8630 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
8633 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
8635 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
8637 /* We don't care about bases that don't have vtables. */
8638 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
8639 return dfs_skip_bases;
8641 /* We're only interested in proper subobjects of the type being
8643 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
8646 /* We're only interested in bases with virtual bases or reachable
8647 via a virtual path from the type being constructed. */
8648 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
8649 || binfo_via_virtual (binfo, data->type_being_constructed)))
8650 return dfs_skip_bases;
8652 /* We're not interested in non-virtual primary bases. */
8653 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
8656 /* Record the index where this secondary vptr can be found. */
8657 if (data->top_level_p)
8659 gcc_assert (!BINFO_VPTR_INDEX (binfo));
8660 BINFO_VPTR_INDEX (binfo) = data->index;
8662 if (BINFO_VIRTUAL_P (binfo))
8664 /* It's a primary virtual base, and this is not a
8665 construction vtable. Find the base this is primary of in
8666 the inheritance graph, and use that base's vtable
8668 while (BINFO_PRIMARY_P (binfo))
8669 binfo = BINFO_INHERITANCE_CHAIN (binfo);
8673 /* Add the initializer for the secondary vptr itself. */
8674 CONSTRUCTOR_APPEND_ELT (data->inits, NULL_TREE, binfo_ctor_vtable (binfo));
8676 /* Advance the vtt index. */
8677 data->index = size_binop (PLUS_EXPR, data->index,
8678 TYPE_SIZE_UNIT (ptr_type_node));
8683 /* Called from build_vtt_inits via dfs_walk. After building
8684 constructor vtables and generating the sub-vtt from them, we need
8685 to restore the BINFO_VTABLES that were scribbled on. DATA is the
8686 binfo of the base whose sub vtt was generated. */
8689 dfs_fixup_binfo_vtbls (tree binfo, void* data)
8691 tree vtable = BINFO_VTABLE (binfo);
8693 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
8694 /* If this class has no vtable, none of its bases do. */
8695 return dfs_skip_bases;
8698 /* This might be a primary base, so have no vtable in this
8702 /* If we scribbled the construction vtable vptr into BINFO, clear it
8704 if (TREE_CODE (vtable) == TREE_LIST
8705 && (TREE_PURPOSE (vtable) == (tree) data))
8706 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
8711 /* Build the construction vtable group for BINFO which is in the
8712 hierarchy dominated by T. */
8715 build_ctor_vtbl_group (tree binfo, tree t)
8721 vec<constructor_elt, va_gc> *v;
8723 /* See if we've already created this construction vtable group. */
8724 id = mangle_ctor_vtbl_for_type (t, binfo);
8725 if (IDENTIFIER_GLOBAL_VALUE (id))
8728 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
8729 /* Build a version of VTBL (with the wrong type) for use in
8730 constructing the addresses of secondary vtables in the
8731 construction vtable group. */
8732 vtbl = build_vtable (t, id, ptr_type_node);
8733 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
8734 /* Don't export construction vtables from shared libraries. Even on
8735 targets that don't support hidden visibility, this tells
8736 can_refer_decl_in_current_unit_p not to assume that it's safe to
8737 access from a different compilation unit (bz 54314). */
8738 DECL_VISIBILITY (vtbl) = VISIBILITY_HIDDEN;
8739 DECL_VISIBILITY_SPECIFIED (vtbl) = true;
8742 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
8743 binfo, vtbl, t, &v);
8745 /* Add the vtables for each of our virtual bases using the vbase in T
8747 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
8749 vbase = TREE_CHAIN (vbase))
8753 if (!BINFO_VIRTUAL_P (vbase))
8755 b = copied_binfo (vbase, binfo);
8757 accumulate_vtbl_inits (b, vbase, binfo, vtbl, t, &v);
8760 /* Figure out the type of the construction vtable. */
8761 type = build_array_of_n_type (vtable_entry_type, v->length ());
8763 TREE_TYPE (vtbl) = type;
8764 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
8765 layout_decl (vtbl, 0);
8767 /* Initialize the construction vtable. */
8768 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
8769 initialize_artificial_var (vtbl, v);
8770 dump_vtable (t, binfo, vtbl);
8773 /* Add the vtbl initializers for BINFO (and its bases other than
8774 non-virtual primaries) to the list of INITS. BINFO is in the
8775 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
8776 the constructor the vtbl inits should be accumulated for. (If this
8777 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
8778 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
8779 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
8780 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
8781 but are not necessarily the same in terms of layout. */
8784 accumulate_vtbl_inits (tree binfo,
8789 vec<constructor_elt, va_gc> **inits)
8793 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8795 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
8797 /* If it doesn't have a vptr, we don't do anything. */
8798 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
8801 /* If we're building a construction vtable, we're not interested in
8802 subobjects that don't require construction vtables. */
8804 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
8805 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
8808 /* Build the initializers for the BINFO-in-T vtable. */
8809 dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, vtbl, t, inits);
8811 /* Walk the BINFO and its bases. We walk in preorder so that as we
8812 initialize each vtable we can figure out at what offset the
8813 secondary vtable lies from the primary vtable. We can't use
8814 dfs_walk here because we need to iterate through bases of BINFO
8815 and RTTI_BINFO simultaneously. */
8816 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8818 /* Skip virtual bases. */
8819 if (BINFO_VIRTUAL_P (base_binfo))
8821 accumulate_vtbl_inits (base_binfo,
8822 BINFO_BASE_BINFO (orig_binfo, i),
8823 rtti_binfo, vtbl, t,
8828 /* Called from accumulate_vtbl_inits. Adds the initializers for the
8829 BINFO vtable to L. */
8832 dfs_accumulate_vtbl_inits (tree binfo,
8837 vec<constructor_elt, va_gc> **l)
8839 tree vtbl = NULL_TREE;
8840 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8844 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
8846 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
8847 primary virtual base. If it is not the same primary in
8848 the hierarchy of T, we'll need to generate a ctor vtable
8849 for it, to place at its location in T. If it is the same
8850 primary, we still need a VTT entry for the vtable, but it
8851 should point to the ctor vtable for the base it is a
8852 primary for within the sub-hierarchy of RTTI_BINFO.
8854 There are three possible cases:
8856 1) We are in the same place.
8857 2) We are a primary base within a lost primary virtual base of
8859 3) We are primary to something not a base of RTTI_BINFO. */
8862 tree last = NULL_TREE;
8864 /* First, look through the bases we are primary to for RTTI_BINFO
8865 or a virtual base. */
8867 while (BINFO_PRIMARY_P (b))
8869 b = BINFO_INHERITANCE_CHAIN (b);
8871 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
8874 /* If we run out of primary links, keep looking down our
8875 inheritance chain; we might be an indirect primary. */
8876 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
8877 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
8881 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
8882 base B and it is a base of RTTI_BINFO, this is case 2. In
8883 either case, we share our vtable with LAST, i.e. the
8884 derived-most base within B of which we are a primary. */
8886 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
8887 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
8888 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
8889 binfo_ctor_vtable after everything's been set up. */
8892 /* Otherwise, this is case 3 and we get our own. */
8894 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
8897 n_inits = vec_safe_length (*l);
8904 /* Add the initializer for this vtable. */
8905 build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
8906 &non_fn_entries, l);
8908 /* Figure out the position to which the VPTR should point. */
8909 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, orig_vtbl);
8910 index = size_binop (MULT_EXPR,
8911 TYPE_SIZE_UNIT (vtable_entry_type),
8912 size_int (non_fn_entries + n_inits));
8913 vtbl = fold_build_pointer_plus (vtbl, index);
8917 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
8918 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
8919 straighten this out. */
8920 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
8921 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
8922 /* Throw away any unneeded intializers. */
8923 (*l)->truncate (n_inits);
8925 /* For an ordinary vtable, set BINFO_VTABLE. */
8926 BINFO_VTABLE (binfo) = vtbl;
8929 static GTY(()) tree abort_fndecl_addr;
8931 /* Construct the initializer for BINFO's virtual function table. BINFO
8932 is part of the hierarchy dominated by T. If we're building a
8933 construction vtable, the ORIG_BINFO is the binfo we should use to
8934 find the actual function pointers to put in the vtable - but they
8935 can be overridden on the path to most-derived in the graph that
8936 ORIG_BINFO belongs. Otherwise,
8937 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
8938 BINFO that should be indicated by the RTTI information in the
8939 vtable; it will be a base class of T, rather than T itself, if we
8940 are building a construction vtable.
8942 The value returned is a TREE_LIST suitable for wrapping in a
8943 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
8944 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
8945 number of non-function entries in the vtable.
8947 It might seem that this function should never be called with a
8948 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
8949 base is always subsumed by a derived class vtable. However, when
8950 we are building construction vtables, we do build vtables for
8951 primary bases; we need these while the primary base is being
8955 build_vtbl_initializer (tree binfo,
8959 int* non_fn_entries_p,
8960 vec<constructor_elt, va_gc> **inits)
8966 vec<tree, va_gc> *vbases;
8969 /* Initialize VID. */
8970 memset (&vid, 0, sizeof (vid));
8973 vid.rtti_binfo = rtti_binfo;
8974 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
8975 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8976 vid.generate_vcall_entries = true;
8977 /* The first vbase or vcall offset is at index -3 in the vtable. */
8978 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
8980 /* Add entries to the vtable for RTTI. */
8981 build_rtti_vtbl_entries (binfo, &vid);
8983 /* Create an array for keeping track of the functions we've
8984 processed. When we see multiple functions with the same
8985 signature, we share the vcall offsets. */
8986 vec_alloc (vid.fns, 32);
8987 /* Add the vcall and vbase offset entries. */
8988 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
8990 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
8991 build_vbase_offset_vtbl_entries. */
8992 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
8993 vec_safe_iterate (vbases, ix, &vbinfo); ix++)
8994 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
8996 /* If the target requires padding between data entries, add that now. */
8997 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
8999 int n_entries = vec_safe_length (vid.inits);
9001 vec_safe_grow (vid.inits, TARGET_VTABLE_DATA_ENTRY_DISTANCE * n_entries);
9003 /* Move data entries into their new positions and add padding
9004 after the new positions. Iterate backwards so we don't
9005 overwrite entries that we would need to process later. */
9006 for (ix = n_entries - 1;
9007 vid.inits->iterate (ix, &e);
9011 int new_position = (TARGET_VTABLE_DATA_ENTRY_DISTANCE * ix
9012 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE - 1));
9014 (*vid.inits)[new_position] = *e;
9016 for (j = 1; j < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++j)
9018 constructor_elt *f = &(*vid.inits)[new_position - j];
9019 f->index = NULL_TREE;
9020 f->value = build1 (NOP_EXPR, vtable_entry_type,
9026 if (non_fn_entries_p)
9027 *non_fn_entries_p = vec_safe_length (vid.inits);
9029 /* The initializers for virtual functions were built up in reverse
9030 order. Straighten them out and add them to the running list in one
9032 jx = vec_safe_length (*inits);
9033 vec_safe_grow (*inits, jx + vid.inits->length ());
9035 for (ix = vid.inits->length () - 1;
9036 vid.inits->iterate (ix, &e);
9040 /* Go through all the ordinary virtual functions, building up
9042 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
9046 tree fn, fn_original;
9047 tree init = NULL_TREE;
9051 if (DECL_THUNK_P (fn))
9053 if (!DECL_NAME (fn))
9055 if (THUNK_ALIAS (fn))
9057 fn = THUNK_ALIAS (fn);
9060 fn_original = THUNK_TARGET (fn);
9063 /* If the only definition of this function signature along our
9064 primary base chain is from a lost primary, this vtable slot will
9065 never be used, so just zero it out. This is important to avoid
9066 requiring extra thunks which cannot be generated with the function.
9068 We first check this in update_vtable_entry_for_fn, so we handle
9069 restored primary bases properly; we also need to do it here so we
9070 zero out unused slots in ctor vtables, rather than filling them
9071 with erroneous values (though harmless, apart from relocation
9073 if (BV_LOST_PRIMARY (v))
9074 init = size_zero_node;
9078 /* Pull the offset for `this', and the function to call, out of
9080 delta = BV_DELTA (v);
9081 vcall_index = BV_VCALL_INDEX (v);
9083 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
9084 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
9086 /* You can't call an abstract virtual function; it's abstract.
9087 So, we replace these functions with __pure_virtual. */
9088 if (DECL_PURE_VIRTUAL_P (fn_original))
9091 if (!TARGET_VTABLE_USES_DESCRIPTORS)
9093 if (abort_fndecl_addr == NULL)
9095 = fold_convert (vfunc_ptr_type_node,
9096 build_fold_addr_expr (fn));
9097 init = abort_fndecl_addr;
9100 /* Likewise for deleted virtuals. */
9101 else if (DECL_DELETED_FN (fn_original))
9103 fn = get_identifier ("__cxa_deleted_virtual");
9104 if (!get_global_value_if_present (fn, &fn))
9105 fn = push_library_fn (fn, (build_function_type_list
9106 (void_type_node, NULL_TREE)),
9107 NULL_TREE, ECF_NORETURN);
9108 if (!TARGET_VTABLE_USES_DESCRIPTORS)
9109 init = fold_convert (vfunc_ptr_type_node,
9110 build_fold_addr_expr (fn));
9114 if (!integer_zerop (delta) || vcall_index)
9116 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
9117 if (!DECL_NAME (fn))
9120 /* Take the address of the function, considering it to be of an
9121 appropriate generic type. */
9122 if (!TARGET_VTABLE_USES_DESCRIPTORS)
9123 init = fold_convert (vfunc_ptr_type_node,
9124 build_fold_addr_expr (fn));
9125 /* Don't refer to a virtual destructor from a constructor
9126 vtable or a vtable for an abstract class, since destroying
9127 an object under construction is undefined behavior and we
9128 don't want it to be considered a candidate for speculative
9129 devirtualization. But do create the thunk for ABI
9131 if (DECL_DESTRUCTOR_P (fn_original)
9132 && (CLASSTYPE_PURE_VIRTUALS (DECL_CONTEXT (fn_original))
9133 || orig_binfo != binfo))
9134 init = size_zero_node;
9138 /* And add it to the chain of initializers. */
9139 if (TARGET_VTABLE_USES_DESCRIPTORS)
9142 if (init == size_zero_node)
9143 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
9144 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
9146 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
9148 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
9149 fn, build_int_cst (NULL_TREE, i));
9150 TREE_CONSTANT (fdesc) = 1;
9152 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, fdesc);
9156 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
9160 /* Adds to vid->inits the initializers for the vbase and vcall
9161 offsets in BINFO, which is in the hierarchy dominated by T. */
9164 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
9168 /* If this is a derived class, we must first create entries
9169 corresponding to the primary base class. */
9170 b = get_primary_binfo (binfo);
9172 build_vcall_and_vbase_vtbl_entries (b, vid);
9174 /* Add the vbase entries for this base. */
9175 build_vbase_offset_vtbl_entries (binfo, vid);
9176 /* Add the vcall entries for this base. */
9177 build_vcall_offset_vtbl_entries (binfo, vid);
9180 /* Returns the initializers for the vbase offset entries in the vtable
9181 for BINFO (which is part of the class hierarchy dominated by T), in
9182 reverse order. VBASE_OFFSET_INDEX gives the vtable index
9183 where the next vbase offset will go. */
9186 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
9190 tree non_primary_binfo;
9192 /* If there are no virtual baseclasses, then there is nothing to
9194 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
9199 /* We might be a primary base class. Go up the inheritance hierarchy
9200 until we find the most derived class of which we are a primary base:
9201 it is the offset of that which we need to use. */
9202 non_primary_binfo = binfo;
9203 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
9207 /* If we have reached a virtual base, then it must be a primary
9208 base (possibly multi-level) of vid->binfo, or we wouldn't
9209 have called build_vcall_and_vbase_vtbl_entries for it. But it
9210 might be a lost primary, so just skip down to vid->binfo. */
9211 if (BINFO_VIRTUAL_P (non_primary_binfo))
9213 non_primary_binfo = vid->binfo;
9217 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
9218 if (get_primary_binfo (b) != non_primary_binfo)
9220 non_primary_binfo = b;
9223 /* Go through the virtual bases, adding the offsets. */
9224 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
9226 vbase = TREE_CHAIN (vbase))
9231 if (!BINFO_VIRTUAL_P (vbase))
9234 /* Find the instance of this virtual base in the complete
9236 b = copied_binfo (vbase, binfo);
9238 /* If we've already got an offset for this virtual base, we
9239 don't need another one. */
9240 if (BINFO_VTABLE_PATH_MARKED (b))
9242 BINFO_VTABLE_PATH_MARKED (b) = 1;
9244 /* Figure out where we can find this vbase offset. */
9245 delta = size_binop (MULT_EXPR,
9248 TYPE_SIZE_UNIT (vtable_entry_type)));
9249 if (vid->primary_vtbl_p)
9250 BINFO_VPTR_FIELD (b) = delta;
9252 if (binfo != TYPE_BINFO (t))
9253 /* The vbase offset had better be the same. */
9254 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
9256 /* The next vbase will come at a more negative offset. */
9257 vid->index = size_binop (MINUS_EXPR, vid->index,
9258 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
9260 /* The initializer is the delta from BINFO to this virtual base.
9261 The vbase offsets go in reverse inheritance-graph order, and
9262 we are walking in inheritance graph order so these end up in
9264 delta = size_diffop_loc (input_location,
9265 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
9267 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE,
9268 fold_build1_loc (input_location, NOP_EXPR,
9269 vtable_entry_type, delta));
9273 /* Adds the initializers for the vcall offset entries in the vtable
9274 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
9278 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
9280 /* We only need these entries if this base is a virtual base. We
9281 compute the indices -- but do not add to the vtable -- when
9282 building the main vtable for a class. */
9283 if (binfo == TYPE_BINFO (vid->derived)
9284 || (BINFO_VIRTUAL_P (binfo)
9285 /* If BINFO is RTTI_BINFO, then (since BINFO does not
9286 correspond to VID->DERIVED), we are building a primary
9287 construction virtual table. Since this is a primary
9288 virtual table, we do not need the vcall offsets for
9290 && binfo != vid->rtti_binfo))
9292 /* We need a vcall offset for each of the virtual functions in this
9293 vtable. For example:
9295 class A { virtual void f (); };
9296 class B1 : virtual public A { virtual void f (); };
9297 class B2 : virtual public A { virtual void f (); };
9298 class C: public B1, public B2 { virtual void f (); };
9300 A C object has a primary base of B1, which has a primary base of A. A
9301 C also has a secondary base of B2, which no longer has a primary base
9302 of A. So the B2-in-C construction vtable needs a secondary vtable for
9303 A, which will adjust the A* to a B2* to call f. We have no way of
9304 knowing what (or even whether) this offset will be when we define B2,
9305 so we store this "vcall offset" in the A sub-vtable and look it up in
9306 a "virtual thunk" for B2::f.
9308 We need entries for all the functions in our primary vtable and
9309 in our non-virtual bases' secondary vtables. */
9311 /* If we are just computing the vcall indices -- but do not need
9312 the actual entries -- not that. */
9313 if (!BINFO_VIRTUAL_P (binfo))
9314 vid->generate_vcall_entries = false;
9315 /* Now, walk through the non-virtual bases, adding vcall offsets. */
9316 add_vcall_offset_vtbl_entries_r (binfo, vid);
9320 /* Build vcall offsets, starting with those for BINFO. */
9323 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
9329 /* Don't walk into virtual bases -- except, of course, for the
9330 virtual base for which we are building vcall offsets. Any
9331 primary virtual base will have already had its offsets generated
9332 through the recursion in build_vcall_and_vbase_vtbl_entries. */
9333 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
9336 /* If BINFO has a primary base, process it first. */
9337 primary_binfo = get_primary_binfo (binfo);
9339 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
9341 /* Add BINFO itself to the list. */
9342 add_vcall_offset_vtbl_entries_1 (binfo, vid);
9344 /* Scan the non-primary bases of BINFO. */
9345 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
9346 if (base_binfo != primary_binfo)
9347 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
9350 /* Called from build_vcall_offset_vtbl_entries_r. */
9353 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
9355 /* Make entries for the rest of the virtuals. */
9358 /* The ABI requires that the methods be processed in declaration
9360 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
9362 orig_fn = DECL_CHAIN (orig_fn))
9363 if (TREE_CODE (orig_fn) == FUNCTION_DECL && DECL_VINDEX (orig_fn))
9364 add_vcall_offset (orig_fn, binfo, vid);
9367 /* Add a vcall offset entry for ORIG_FN to the vtable. */
9370 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
9376 /* If there is already an entry for a function with the same
9377 signature as FN, then we do not need a second vcall offset.
9378 Check the list of functions already present in the derived
9380 FOR_EACH_VEC_SAFE_ELT (vid->fns, i, derived_entry)
9382 if (same_signature_p (derived_entry, orig_fn)
9383 /* We only use one vcall offset for virtual destructors,
9384 even though there are two virtual table entries. */
9385 || (DECL_DESTRUCTOR_P (derived_entry)
9386 && DECL_DESTRUCTOR_P (orig_fn)))
9390 /* If we are building these vcall offsets as part of building
9391 the vtable for the most derived class, remember the vcall
9393 if (vid->binfo == TYPE_BINFO (vid->derived))
9395 tree_pair_s elt = {orig_fn, vid->index};
9396 vec_safe_push (CLASSTYPE_VCALL_INDICES (vid->derived), elt);
9399 /* The next vcall offset will be found at a more negative
9401 vid->index = size_binop (MINUS_EXPR, vid->index,
9402 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
9404 /* Keep track of this function. */
9405 vec_safe_push (vid->fns, orig_fn);
9407 if (vid->generate_vcall_entries)
9412 /* Find the overriding function. */
9413 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
9414 if (fn == error_mark_node)
9415 vcall_offset = build_zero_cst (vtable_entry_type);
9418 base = TREE_VALUE (fn);
9420 /* The vbase we're working on is a primary base of
9421 vid->binfo. But it might be a lost primary, so its
9422 BINFO_OFFSET might be wrong, so we just use the
9423 BINFO_OFFSET from vid->binfo. */
9424 vcall_offset = size_diffop_loc (input_location,
9425 BINFO_OFFSET (base),
9426 BINFO_OFFSET (vid->binfo));
9427 vcall_offset = fold_build1_loc (input_location,
9428 NOP_EXPR, vtable_entry_type,
9431 /* Add the initializer to the vtable. */
9432 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, vcall_offset);
9436 /* Return vtbl initializers for the RTTI entries corresponding to the
9437 BINFO's vtable. The RTTI entries should indicate the object given
9438 by VID->rtti_binfo. */
9441 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
9449 t = BINFO_TYPE (vid->rtti_binfo);
9451 /* To find the complete object, we will first convert to our most
9452 primary base, and then add the offset in the vtbl to that value. */
9454 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
9455 && !BINFO_LOST_PRIMARY_P (b))
9459 primary_base = get_primary_binfo (b);
9460 gcc_assert (BINFO_PRIMARY_P (primary_base)
9461 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
9464 offset = size_diffop_loc (input_location,
9465 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
9467 /* The second entry is the address of the typeinfo object. */
9469 decl = build_address (get_tinfo_decl (t));
9471 decl = integer_zero_node;
9473 /* Convert the declaration to a type that can be stored in the
9475 init = build_nop (vfunc_ptr_type_node, decl);
9476 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
9478 /* Add the offset-to-top entry. It comes earlier in the vtable than
9479 the typeinfo entry. Convert the offset to look like a
9480 function pointer, so that we can put it in the vtable. */
9481 init = build_nop (vfunc_ptr_type_node, offset);
9482 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
9485 /* TRUE iff TYPE is uniquely derived from PARENT. Ignores
9489 uniquely_derived_from_p (tree parent, tree type)
9491 tree base = lookup_base (type, parent, ba_unique, NULL, tf_none);
9492 return base && base != error_mark_node;
9495 /* TRUE iff TYPE is publicly & uniquely derived from PARENT. */
9498 publicly_uniquely_derived_p (tree parent, tree type)
9500 tree base = lookup_base (type, parent, ba_ignore_scope | ba_check,
9502 return base && base != error_mark_node;
9505 /* CTX1 and CTX2 are declaration contexts. Return the innermost common
9506 class between them, if any. */
9509 common_enclosing_class (tree ctx1, tree ctx2)
9511 if (!TYPE_P (ctx1) || !TYPE_P (ctx2))
9513 gcc_assert (ctx1 == TYPE_MAIN_VARIANT (ctx1)
9514 && ctx2 == TYPE_MAIN_VARIANT (ctx2));
9517 for (tree t = ctx1; TYPE_P (t); t = TYPE_CONTEXT (t))
9518 TYPE_MARKED_P (t) = true;
9519 tree found = NULL_TREE;
9520 for (tree t = ctx2; TYPE_P (t); t = TYPE_CONTEXT (t))
9521 if (TYPE_MARKED_P (t))
9526 for (tree t = ctx1; TYPE_P (t); t = TYPE_CONTEXT (t))
9527 TYPE_MARKED_P (t) = false;
9531 #include "gt-cp-class.h"