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[official-gcc.git] / main / gcc / cp / class.c
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1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987-2014 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)
10 any later version.
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. */
24 #include "config.h"
25 #include "system.h"
26 #include "coretypes.h"
27 #include "tm.h"
28 #include "tree.h"
29 #include "stringpool.h"
30 #include "stor-layout.h"
31 #include "attribs.h"
32 #include "pointer-set.h"
33 #include "hash-table.h"
34 #include "cp-tree.h"
35 #include "flags.h"
36 #include "toplev.h"
37 #include "target.h"
38 #include "convert.h"
39 #include "cgraph.h"
40 #include "dumpfile.h"
41 #include "splay-tree.h"
42 #include "gimplify.h"
44 /* The number of nested classes being processed. If we are not in the
45 scope of any class, this is zero. */
47 int current_class_depth;
49 /* In order to deal with nested classes, we keep a stack of classes.
50 The topmost entry is the innermost class, and is the entry at index
51 CURRENT_CLASS_DEPTH */
53 typedef struct class_stack_node {
54 /* The name of the class. */
55 tree name;
57 /* The _TYPE node for the class. */
58 tree type;
60 /* The access specifier pending for new declarations in the scope of
61 this class. */
62 tree access;
64 /* If were defining TYPE, the names used in this class. */
65 splay_tree names_used;
67 /* Nonzero if this class is no longer open, because of a call to
68 push_to_top_level. */
69 size_t hidden;
70 }* class_stack_node_t;
72 typedef struct vtbl_init_data_s
74 /* The base for which we're building initializers. */
75 tree binfo;
76 /* The type of the most-derived type. */
77 tree derived;
78 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
79 unless ctor_vtbl_p is true. */
80 tree rtti_binfo;
81 /* The negative-index vtable initializers built up so far. These
82 are in order from least negative index to most negative index. */
83 vec<constructor_elt, va_gc> *inits;
84 /* The binfo for the virtual base for which we're building
85 vcall offset initializers. */
86 tree vbase;
87 /* The functions in vbase for which we have already provided vcall
88 offsets. */
89 vec<tree, va_gc> *fns;
90 /* The vtable index of the next vcall or vbase offset. */
91 tree index;
92 /* Nonzero if we are building the initializer for the primary
93 vtable. */
94 int primary_vtbl_p;
95 /* Nonzero if we are building the initializer for a construction
96 vtable. */
97 int ctor_vtbl_p;
98 /* True when adding vcall offset entries to the vtable. False when
99 merely computing the indices. */
100 bool generate_vcall_entries;
101 } vtbl_init_data;
103 /* The type of a function passed to walk_subobject_offsets. */
104 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
106 /* The stack itself. This is a dynamically resized array. The
107 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
108 static int current_class_stack_size;
109 static class_stack_node_t current_class_stack;
111 /* The size of the largest empty class seen in this translation unit. */
112 static GTY (()) tree sizeof_biggest_empty_class;
114 /* An array of all local classes present in this translation unit, in
115 declaration order. */
116 vec<tree, va_gc> *local_classes;
118 static tree get_vfield_name (tree);
119 static void finish_struct_anon (tree);
120 static tree get_vtable_name (tree);
121 static tree get_basefndecls (tree, tree);
122 static int build_primary_vtable (tree, tree);
123 static int build_secondary_vtable (tree);
124 static void finish_vtbls (tree);
125 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
126 static void finish_struct_bits (tree);
127 static int alter_access (tree, tree, tree);
128 static void handle_using_decl (tree, tree);
129 static tree dfs_modify_vtables (tree, void *);
130 static tree modify_all_vtables (tree, tree);
131 static void determine_primary_bases (tree);
132 static void finish_struct_methods (tree);
133 static void maybe_warn_about_overly_private_class (tree);
134 static int method_name_cmp (const void *, const void *);
135 static int resort_method_name_cmp (const void *, const void *);
136 static void add_implicitly_declared_members (tree, tree*, int, int);
137 static tree fixed_type_or_null (tree, int *, int *);
138 static tree build_simple_base_path (tree expr, tree binfo);
139 static tree build_vtbl_ref_1 (tree, tree);
140 static void build_vtbl_initializer (tree, tree, tree, tree, int *,
141 vec<constructor_elt, va_gc> **);
142 static int count_fields (tree);
143 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
144 static void insert_into_classtype_sorted_fields (tree, tree, int);
145 static bool check_bitfield_decl (tree);
146 static void check_field_decl (tree, tree, int *, int *, int *);
147 static void check_field_decls (tree, tree *, int *, int *);
148 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
149 static void build_base_fields (record_layout_info, splay_tree, tree *);
150 static void check_methods (tree);
151 static void remove_zero_width_bit_fields (tree);
152 static void check_bases (tree, int *, int *);
153 static void check_bases_and_members (tree);
154 static tree create_vtable_ptr (tree, tree *);
155 static void include_empty_classes (record_layout_info);
156 static void layout_class_type (tree, tree *);
157 static void propagate_binfo_offsets (tree, tree);
158 static void layout_virtual_bases (record_layout_info, splay_tree);
159 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
160 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
161 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
162 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
163 static void add_vcall_offset (tree, tree, vtbl_init_data *);
164 static void layout_vtable_decl (tree, int);
165 static tree dfs_find_final_overrider_pre (tree, void *);
166 static tree dfs_find_final_overrider_post (tree, void *);
167 static tree find_final_overrider (tree, tree, tree);
168 static int make_new_vtable (tree, tree);
169 static tree get_primary_binfo (tree);
170 static int maybe_indent_hierarchy (FILE *, int, int);
171 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
172 static void dump_class_hierarchy (tree);
173 static void dump_class_hierarchy_1 (FILE *, int, tree);
174 static void dump_array (FILE *, tree);
175 static void dump_vtable (tree, tree, tree);
176 static void dump_vtt (tree, tree);
177 static void dump_thunk (FILE *, int, tree);
178 static tree build_vtable (tree, tree, tree);
179 static void initialize_vtable (tree, vec<constructor_elt, va_gc> *);
180 static void layout_nonempty_base_or_field (record_layout_info,
181 tree, tree, splay_tree);
182 static tree end_of_class (tree, int);
183 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
184 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree,
185 vec<constructor_elt, va_gc> **);
186 static void dfs_accumulate_vtbl_inits (tree, tree, tree, tree, tree,
187 vec<constructor_elt, va_gc> **);
188 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
189 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
190 static void clone_constructors_and_destructors (tree);
191 static tree build_clone (tree, tree);
192 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
193 static void build_ctor_vtbl_group (tree, tree);
194 static void build_vtt (tree);
195 static tree binfo_ctor_vtable (tree);
196 static void build_vtt_inits (tree, tree, vec<constructor_elt, va_gc> **,
197 tree *);
198 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
199 static tree dfs_fixup_binfo_vtbls (tree, void *);
200 static int record_subobject_offset (tree, tree, splay_tree);
201 static int check_subobject_offset (tree, tree, splay_tree);
202 static int walk_subobject_offsets (tree, subobject_offset_fn,
203 tree, splay_tree, tree, int);
204 static void record_subobject_offsets (tree, tree, splay_tree, bool);
205 static int layout_conflict_p (tree, tree, splay_tree, int);
206 static int splay_tree_compare_integer_csts (splay_tree_key k1,
207 splay_tree_key k2);
208 static void warn_about_ambiguous_bases (tree);
209 static bool type_requires_array_cookie (tree);
210 static bool contains_empty_class_p (tree);
211 static bool base_derived_from (tree, tree);
212 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
213 static tree end_of_base (tree);
214 static tree get_vcall_index (tree, tree);
216 /* Variables shared between class.c and call.c. */
218 int n_vtables = 0;
219 int n_vtable_entries = 0;
220 int n_vtable_searches = 0;
221 int n_vtable_elems = 0;
222 int n_convert_harshness = 0;
223 int n_compute_conversion_costs = 0;
224 int n_inner_fields_searched = 0;
226 /* Convert to or from a base subobject. EXPR is an expression of type
227 `A' or `A*', an expression of type `B' or `B*' is returned. To
228 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
229 the B base instance within A. To convert base A to derived B, CODE
230 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
231 In this latter case, A must not be a morally virtual base of B.
232 NONNULL is true if EXPR is known to be non-NULL (this is only
233 needed when EXPR is of pointer type). CV qualifiers are preserved
234 from EXPR. */
236 tree
237 build_base_path (enum tree_code code,
238 tree expr,
239 tree binfo,
240 int nonnull,
241 tsubst_flags_t complain)
243 tree v_binfo = NULL_TREE;
244 tree d_binfo = NULL_TREE;
245 tree probe;
246 tree offset;
247 tree target_type;
248 tree null_test = NULL;
249 tree ptr_target_type;
250 int fixed_type_p;
251 int want_pointer = TYPE_PTR_P (TREE_TYPE (expr));
252 bool has_empty = false;
253 bool virtual_access;
255 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
256 return error_mark_node;
258 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
260 d_binfo = probe;
261 if (is_empty_class (BINFO_TYPE (probe)))
262 has_empty = true;
263 if (!v_binfo && BINFO_VIRTUAL_P (probe))
264 v_binfo = probe;
267 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
268 if (want_pointer)
269 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
271 if (code == PLUS_EXPR
272 && !SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe))
274 /* This can happen when adjust_result_of_qualified_name_lookup can't
275 find a unique base binfo in a call to a member function. We
276 couldn't give the diagnostic then since we might have been calling
277 a static member function, so we do it now. */
278 if (complain & tf_error)
280 tree base = lookup_base (probe, BINFO_TYPE (d_binfo),
281 ba_unique, NULL, complain);
282 gcc_assert (base == error_mark_node);
284 return error_mark_node;
287 gcc_assert ((code == MINUS_EXPR
288 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
289 || code == PLUS_EXPR);
291 if (binfo == d_binfo)
292 /* Nothing to do. */
293 return expr;
295 if (code == MINUS_EXPR && v_binfo)
297 if (complain & tf_error)
299 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (v_binfo)))
301 if (want_pointer)
302 error ("cannot convert from pointer to base class %qT to "
303 "pointer to derived class %qT because the base is "
304 "virtual", BINFO_TYPE (binfo), BINFO_TYPE (d_binfo));
305 else
306 error ("cannot convert from base class %qT to derived "
307 "class %qT because the base is virtual",
308 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo));
310 else
312 if (want_pointer)
313 error ("cannot convert from pointer to base class %qT to "
314 "pointer to derived class %qT via virtual base %qT",
315 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo),
316 BINFO_TYPE (v_binfo));
317 else
318 error ("cannot convert from base class %qT to derived "
319 "class %qT via virtual base %qT", BINFO_TYPE (binfo),
320 BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
323 return error_mark_node;
326 if (!want_pointer)
327 /* This must happen before the call to save_expr. */
328 expr = cp_build_addr_expr (expr, complain);
329 else
330 expr = mark_rvalue_use (expr);
332 offset = BINFO_OFFSET (binfo);
333 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
334 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
335 /* TARGET_TYPE has been extracted from BINFO, and, is therefore always
336 cv-unqualified. Extract the cv-qualifiers from EXPR so that the
337 expression returned matches the input. */
338 target_type = cp_build_qualified_type
339 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
340 ptr_target_type = build_pointer_type (target_type);
342 /* Do we need to look in the vtable for the real offset? */
343 virtual_access = (v_binfo && fixed_type_p <= 0);
345 /* Don't bother with the calculations inside sizeof; they'll ICE if the
346 source type is incomplete and the pointer value doesn't matter. In a
347 template (even in fold_non_dependent_expr), we don't have vtables set
348 up properly yet, and the value doesn't matter there either; we're just
349 interested in the result of overload resolution. */
350 if (cp_unevaluated_operand != 0
351 || in_template_function ())
353 expr = build_nop (ptr_target_type, expr);
354 if (!want_pointer)
355 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
356 return expr;
359 /* If we're in an NSDMI, we don't have the full constructor context yet
360 that we need for converting to a virtual base, so just build a stub
361 CONVERT_EXPR and expand it later in bot_replace. */
362 if (virtual_access && fixed_type_p < 0
363 && current_scope () != current_function_decl)
365 expr = build1 (CONVERT_EXPR, ptr_target_type, expr);
366 CONVERT_EXPR_VBASE_PATH (expr) = true;
367 if (!want_pointer)
368 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
369 return expr;
372 /* Do we need to check for a null pointer? */
373 if (want_pointer && !nonnull)
375 /* If we know the conversion will not actually change the value
376 of EXPR, then we can avoid testing the expression for NULL.
377 We have to avoid generating a COMPONENT_REF for a base class
378 field, because other parts of the compiler know that such
379 expressions are always non-NULL. */
380 if (!virtual_access && integer_zerop (offset))
381 return build_nop (ptr_target_type, expr);
382 null_test = error_mark_node;
385 /* Protect against multiple evaluation if necessary. */
386 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
387 expr = save_expr (expr);
389 /* Now that we've saved expr, build the real null test. */
390 if (null_test)
392 tree zero = cp_convert (TREE_TYPE (expr), nullptr_node, complain);
393 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
394 expr, zero);
397 /* If this is a simple base reference, express it as a COMPONENT_REF. */
398 if (code == PLUS_EXPR && !virtual_access
399 /* We don't build base fields for empty bases, and they aren't very
400 interesting to the optimizers anyway. */
401 && !has_empty)
403 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
404 expr = build_simple_base_path (expr, binfo);
405 if (want_pointer)
406 expr = build_address (expr);
407 target_type = TREE_TYPE (expr);
408 goto out;
411 if (virtual_access)
413 /* Going via virtual base V_BINFO. We need the static offset
414 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
415 V_BINFO. That offset is an entry in D_BINFO's vtable. */
416 tree v_offset;
418 if (fixed_type_p < 0 && in_base_initializer)
420 /* In a base member initializer, we cannot rely on the
421 vtable being set up. We have to indirect via the
422 vtt_parm. */
423 tree t;
425 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
426 t = build_pointer_type (t);
427 v_offset = convert (t, current_vtt_parm);
428 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
430 else
431 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, RO_NULL,
432 complain),
433 TREE_TYPE (TREE_TYPE (expr)));
435 if (v_offset == error_mark_node)
436 return error_mark_node;
438 v_offset = fold_build_pointer_plus (v_offset, BINFO_VPTR_FIELD (v_binfo));
439 v_offset = build1 (NOP_EXPR,
440 build_pointer_type (ptrdiff_type_node),
441 v_offset);
442 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
443 TREE_CONSTANT (v_offset) = 1;
445 offset = convert_to_integer (ptrdiff_type_node,
446 size_diffop_loc (input_location, offset,
447 BINFO_OFFSET (v_binfo)));
449 if (!integer_zerop (offset))
450 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
452 if (fixed_type_p < 0)
453 /* Negative fixed_type_p means this is a constructor or destructor;
454 virtual base layout is fixed in in-charge [cd]tors, but not in
455 base [cd]tors. */
456 offset = build3 (COND_EXPR, ptrdiff_type_node,
457 build2 (EQ_EXPR, boolean_type_node,
458 current_in_charge_parm, integer_zero_node),
459 v_offset,
460 convert_to_integer (ptrdiff_type_node,
461 BINFO_OFFSET (binfo)));
462 else
463 offset = v_offset;
466 if (want_pointer)
467 target_type = ptr_target_type;
469 expr = build1 (NOP_EXPR, ptr_target_type, expr);
471 if (!integer_zerop (offset))
473 offset = fold_convert (sizetype, offset);
474 if (code == MINUS_EXPR)
475 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
476 expr = fold_build_pointer_plus (expr, offset);
478 else
479 null_test = NULL;
481 if (!want_pointer)
482 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
484 out:
485 if (null_test)
486 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
487 build_zero_cst (target_type));
489 return expr;
492 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
493 Perform a derived-to-base conversion by recursively building up a
494 sequence of COMPONENT_REFs to the appropriate base fields. */
496 static tree
497 build_simple_base_path (tree expr, tree binfo)
499 tree type = BINFO_TYPE (binfo);
500 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
501 tree field;
503 if (d_binfo == NULL_TREE)
505 tree temp;
507 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
509 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
510 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
511 an lvalue in the front end; only _DECLs and _REFs are lvalues
512 in the back end. */
513 temp = unary_complex_lvalue (ADDR_EXPR, expr);
514 if (temp)
515 expr = cp_build_indirect_ref (temp, RO_NULL, tf_warning_or_error);
517 return expr;
520 /* Recurse. */
521 expr = build_simple_base_path (expr, d_binfo);
523 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
524 field; field = DECL_CHAIN (field))
525 /* Is this the base field created by build_base_field? */
526 if (TREE_CODE (field) == FIELD_DECL
527 && DECL_FIELD_IS_BASE (field)
528 && TREE_TYPE (field) == type
529 /* If we're looking for a field in the most-derived class,
530 also check the field offset; we can have two base fields
531 of the same type if one is an indirect virtual base and one
532 is a direct non-virtual base. */
533 && (BINFO_INHERITANCE_CHAIN (d_binfo)
534 || tree_int_cst_equal (byte_position (field),
535 BINFO_OFFSET (binfo))))
537 /* We don't use build_class_member_access_expr here, as that
538 has unnecessary checks, and more importantly results in
539 recursive calls to dfs_walk_once. */
540 int type_quals = cp_type_quals (TREE_TYPE (expr));
542 expr = build3 (COMPONENT_REF,
543 cp_build_qualified_type (type, type_quals),
544 expr, field, NULL_TREE);
545 expr = fold_if_not_in_template (expr);
547 /* Mark the expression const or volatile, as appropriate.
548 Even though we've dealt with the type above, we still have
549 to mark the expression itself. */
550 if (type_quals & TYPE_QUAL_CONST)
551 TREE_READONLY (expr) = 1;
552 if (type_quals & TYPE_QUAL_VOLATILE)
553 TREE_THIS_VOLATILE (expr) = 1;
555 return expr;
558 /* Didn't find the base field?!? */
559 gcc_unreachable ();
562 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
563 type is a class type or a pointer to a class type. In the former
564 case, TYPE is also a class type; in the latter it is another
565 pointer type. If CHECK_ACCESS is true, an error message is emitted
566 if TYPE is inaccessible. If OBJECT has pointer type, the value is
567 assumed to be non-NULL. */
569 tree
570 convert_to_base (tree object, tree type, bool check_access, bool nonnull,
571 tsubst_flags_t complain)
573 tree binfo;
574 tree object_type;
576 if (TYPE_PTR_P (TREE_TYPE (object)))
578 object_type = TREE_TYPE (TREE_TYPE (object));
579 type = TREE_TYPE (type);
581 else
582 object_type = TREE_TYPE (object);
584 binfo = lookup_base (object_type, type, check_access ? ba_check : ba_unique,
585 NULL, complain);
586 if (!binfo || binfo == error_mark_node)
587 return error_mark_node;
589 return build_base_path (PLUS_EXPR, object, binfo, nonnull, complain);
592 /* EXPR is an expression with unqualified class type. BASE is a base
593 binfo of that class type. Returns EXPR, converted to the BASE
594 type. This function assumes that EXPR is the most derived class;
595 therefore virtual bases can be found at their static offsets. */
597 tree
598 convert_to_base_statically (tree expr, tree base)
600 tree expr_type;
602 expr_type = TREE_TYPE (expr);
603 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
605 /* If this is a non-empty base, use a COMPONENT_REF. */
606 if (!is_empty_class (BINFO_TYPE (base)))
607 return build_simple_base_path (expr, base);
609 /* We use fold_build2 and fold_convert below to simplify the trees
610 provided to the optimizers. It is not safe to call these functions
611 when processing a template because they do not handle C++-specific
612 trees. */
613 gcc_assert (!processing_template_decl);
614 expr = cp_build_addr_expr (expr, tf_warning_or_error);
615 if (!integer_zerop (BINFO_OFFSET (base)))
616 expr = fold_build_pointer_plus_loc (input_location,
617 expr, BINFO_OFFSET (base));
618 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
619 expr = build_fold_indirect_ref_loc (input_location, expr);
622 return expr;
626 tree
627 build_vfield_ref (tree datum, tree type)
629 tree vfield, vcontext;
631 if (datum == error_mark_node
632 /* Can happen in case of duplicate base types (c++/59082). */
633 || !TYPE_VFIELD (type))
634 return error_mark_node;
636 /* First, convert to the requested type. */
637 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
638 datum = convert_to_base (datum, type, /*check_access=*/false,
639 /*nonnull=*/true, tf_warning_or_error);
641 /* Second, the requested type may not be the owner of its own vptr.
642 If not, convert to the base class that owns it. We cannot use
643 convert_to_base here, because VCONTEXT may appear more than once
644 in the inheritance hierarchy of TYPE, and thus direct conversion
645 between the types may be ambiguous. Following the path back up
646 one step at a time via primary bases avoids the problem. */
647 vfield = TYPE_VFIELD (type);
648 vcontext = DECL_CONTEXT (vfield);
649 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
651 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
652 type = TREE_TYPE (datum);
655 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
658 /* Given an object INSTANCE, return an expression which yields the
659 vtable element corresponding to INDEX. There are many special
660 cases for INSTANCE which we take care of here, mainly to avoid
661 creating extra tree nodes when we don't have to. */
663 static tree
664 build_vtbl_ref_1 (tree instance, tree idx)
666 tree aref;
667 tree vtbl = NULL_TREE;
669 /* Try to figure out what a reference refers to, and
670 access its virtual function table directly. */
672 int cdtorp = 0;
673 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
675 tree basetype = non_reference (TREE_TYPE (instance));
677 if (fixed_type && !cdtorp)
679 tree binfo = lookup_base (fixed_type, basetype,
680 ba_unique, NULL, tf_none);
681 if (binfo && binfo != error_mark_node)
682 vtbl = unshare_expr (BINFO_VTABLE (binfo));
685 if (!vtbl)
686 vtbl = build_vfield_ref (instance, basetype);
688 aref = build_array_ref (input_location, vtbl, idx);
689 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
691 return aref;
694 tree
695 build_vtbl_ref (tree instance, tree idx)
697 tree aref = build_vtbl_ref_1 (instance, idx);
699 return aref;
702 /* Given a stable object pointer INSTANCE_PTR, return an expression which
703 yields a function pointer corresponding to vtable element INDEX. */
705 tree
706 build_vfn_ref (tree instance_ptr, tree idx)
708 tree aref;
710 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, RO_NULL,
711 tf_warning_or_error),
712 idx);
714 /* When using function descriptors, the address of the
715 vtable entry is treated as a function pointer. */
716 if (TARGET_VTABLE_USES_DESCRIPTORS)
717 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
718 cp_build_addr_expr (aref, tf_warning_or_error));
720 /* Remember this as a method reference, for later devirtualization. */
721 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
723 return aref;
726 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
727 for the given TYPE. */
729 static tree
730 get_vtable_name (tree type)
732 return mangle_vtbl_for_type (type);
735 /* DECL is an entity associated with TYPE, like a virtual table or an
736 implicitly generated constructor. Determine whether or not DECL
737 should have external or internal linkage at the object file
738 level. This routine does not deal with COMDAT linkage and other
739 similar complexities; it simply sets TREE_PUBLIC if it possible for
740 entities in other translation units to contain copies of DECL, in
741 the abstract. */
743 void
744 set_linkage_according_to_type (tree /*type*/, tree decl)
746 TREE_PUBLIC (decl) = 1;
747 determine_visibility (decl);
750 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
751 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
752 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
754 static tree
755 build_vtable (tree class_type, tree name, tree vtable_type)
757 tree decl;
759 decl = build_lang_decl (VAR_DECL, name, vtable_type);
760 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
761 now to avoid confusion in mangle_decl. */
762 SET_DECL_ASSEMBLER_NAME (decl, name);
763 DECL_CONTEXT (decl) = class_type;
764 DECL_ARTIFICIAL (decl) = 1;
765 TREE_STATIC (decl) = 1;
766 TREE_READONLY (decl) = 1;
767 DECL_VIRTUAL_P (decl) = 1;
768 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
769 DECL_VTABLE_OR_VTT_P (decl) = 1;
770 /* At one time the vtable info was grabbed 2 words at a time. This
771 fails on sparc unless you have 8-byte alignment. (tiemann) */
772 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
773 DECL_ALIGN (decl));
774 set_linkage_according_to_type (class_type, decl);
775 /* The vtable has not been defined -- yet. */
776 DECL_EXTERNAL (decl) = 1;
777 DECL_NOT_REALLY_EXTERN (decl) = 1;
779 /* Mark the VAR_DECL node representing the vtable itself as a
780 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
781 is rather important that such things be ignored because any
782 effort to actually generate DWARF for them will run into
783 trouble when/if we encounter code like:
785 #pragma interface
786 struct S { virtual void member (); };
788 because the artificial declaration of the vtable itself (as
789 manufactured by the g++ front end) will say that the vtable is
790 a static member of `S' but only *after* the debug output for
791 the definition of `S' has already been output. This causes
792 grief because the DWARF entry for the definition of the vtable
793 will try to refer back to an earlier *declaration* of the
794 vtable as a static member of `S' and there won't be one. We
795 might be able to arrange to have the "vtable static member"
796 attached to the member list for `S' before the debug info for
797 `S' get written (which would solve the problem) but that would
798 require more intrusive changes to the g++ front end. */
799 DECL_IGNORED_P (decl) = 1;
801 return decl;
804 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
805 or even complete. If this does not exist, create it. If COMPLETE is
806 nonzero, then complete the definition of it -- that will render it
807 impossible to actually build the vtable, but is useful to get at those
808 which are known to exist in the runtime. */
810 tree
811 get_vtable_decl (tree type, int complete)
813 tree decl;
815 if (CLASSTYPE_VTABLES (type))
816 return CLASSTYPE_VTABLES (type);
818 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
819 CLASSTYPE_VTABLES (type) = decl;
821 if (complete)
823 DECL_EXTERNAL (decl) = 1;
824 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
827 return decl;
830 /* Build the primary virtual function table for TYPE. If BINFO is
831 non-NULL, build the vtable starting with the initial approximation
832 that it is the same as the one which is the head of the association
833 list. Returns a nonzero value if a new vtable is actually
834 created. */
836 static int
837 build_primary_vtable (tree binfo, tree type)
839 tree decl;
840 tree virtuals;
842 decl = get_vtable_decl (type, /*complete=*/0);
844 if (binfo)
846 if (BINFO_NEW_VTABLE_MARKED (binfo))
847 /* We have already created a vtable for this base, so there's
848 no need to do it again. */
849 return 0;
851 virtuals = copy_list (BINFO_VIRTUALS (binfo));
852 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
853 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
854 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
856 else
858 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
859 virtuals = NULL_TREE;
862 if (GATHER_STATISTICS)
864 n_vtables += 1;
865 n_vtable_elems += list_length (virtuals);
868 /* Initialize the association list for this type, based
869 on our first approximation. */
870 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
871 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
872 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
873 return 1;
876 /* Give BINFO a new virtual function table which is initialized
877 with a skeleton-copy of its original initialization. The only
878 entry that changes is the `delta' entry, so we can really
879 share a lot of structure.
881 FOR_TYPE is the most derived type which caused this table to
882 be needed.
884 Returns nonzero if we haven't met BINFO before.
886 The order in which vtables are built (by calling this function) for
887 an object must remain the same, otherwise a binary incompatibility
888 can result. */
890 static int
891 build_secondary_vtable (tree binfo)
893 if (BINFO_NEW_VTABLE_MARKED (binfo))
894 /* We already created a vtable for this base. There's no need to
895 do it again. */
896 return 0;
898 /* Remember that we've created a vtable for this BINFO, so that we
899 don't try to do so again. */
900 SET_BINFO_NEW_VTABLE_MARKED (binfo);
902 /* Make fresh virtual list, so we can smash it later. */
903 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
905 /* Secondary vtables are laid out as part of the same structure as
906 the primary vtable. */
907 BINFO_VTABLE (binfo) = NULL_TREE;
908 return 1;
911 /* Create a new vtable for BINFO which is the hierarchy dominated by
912 T. Return nonzero if we actually created a new vtable. */
914 static int
915 make_new_vtable (tree t, tree binfo)
917 if (binfo == TYPE_BINFO (t))
918 /* In this case, it is *type*'s vtable we are modifying. We start
919 with the approximation that its vtable is that of the
920 immediate base class. */
921 return build_primary_vtable (binfo, t);
922 else
923 /* This is our very own copy of `basetype' to play with. Later,
924 we will fill in all the virtual functions that override the
925 virtual functions in these base classes which are not defined
926 by the current type. */
927 return build_secondary_vtable (binfo);
930 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
931 (which is in the hierarchy dominated by T) list FNDECL as its
932 BV_FN. DELTA is the required constant adjustment from the `this'
933 pointer where the vtable entry appears to the `this' required when
934 the function is actually called. */
936 static void
937 modify_vtable_entry (tree t,
938 tree binfo,
939 tree fndecl,
940 tree delta,
941 tree *virtuals)
943 tree v;
945 v = *virtuals;
947 if (fndecl != BV_FN (v)
948 || !tree_int_cst_equal (delta, BV_DELTA (v)))
950 /* We need a new vtable for BINFO. */
951 if (make_new_vtable (t, binfo))
953 /* If we really did make a new vtable, we also made a copy
954 of the BINFO_VIRTUALS list. Now, we have to find the
955 corresponding entry in that list. */
956 *virtuals = BINFO_VIRTUALS (binfo);
957 while (BV_FN (*virtuals) != BV_FN (v))
958 *virtuals = TREE_CHAIN (*virtuals);
959 v = *virtuals;
962 BV_DELTA (v) = delta;
963 BV_VCALL_INDEX (v) = NULL_TREE;
964 BV_FN (v) = fndecl;
969 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
970 the USING_DECL naming METHOD. Returns true if the method could be
971 added to the method vec. */
973 bool
974 add_method (tree type, tree method, tree using_decl)
976 unsigned slot;
977 tree overload;
978 bool template_conv_p = false;
979 bool conv_p;
980 vec<tree, va_gc> *method_vec;
981 bool complete_p;
982 bool insert_p = false;
983 tree current_fns;
984 tree fns;
986 if (method == error_mark_node)
987 return false;
989 complete_p = COMPLETE_TYPE_P (type);
990 conv_p = DECL_CONV_FN_P (method);
991 if (conv_p)
992 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
993 && DECL_TEMPLATE_CONV_FN_P (method));
995 method_vec = CLASSTYPE_METHOD_VEC (type);
996 if (!method_vec)
998 /* Make a new method vector. We start with 8 entries. We must
999 allocate at least two (for constructors and destructors), and
1000 we're going to end up with an assignment operator at some
1001 point as well. */
1002 vec_alloc (method_vec, 8);
1003 /* Create slots for constructors and destructors. */
1004 method_vec->quick_push (NULL_TREE);
1005 method_vec->quick_push (NULL_TREE);
1006 CLASSTYPE_METHOD_VEC (type) = method_vec;
1009 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
1010 grok_special_member_properties (method);
1012 /* Constructors and destructors go in special slots. */
1013 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
1014 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
1015 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1017 slot = CLASSTYPE_DESTRUCTOR_SLOT;
1019 if (TYPE_FOR_JAVA (type))
1021 if (!DECL_ARTIFICIAL (method))
1022 error ("Java class %qT cannot have a destructor", type);
1023 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
1024 error ("Java class %qT cannot have an implicit non-trivial "
1025 "destructor",
1026 type);
1029 else
1031 tree m;
1033 insert_p = true;
1034 /* See if we already have an entry with this name. */
1035 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1036 vec_safe_iterate (method_vec, slot, &m);
1037 ++slot)
1039 m = OVL_CURRENT (m);
1040 if (template_conv_p)
1042 if (TREE_CODE (m) == TEMPLATE_DECL
1043 && DECL_TEMPLATE_CONV_FN_P (m))
1044 insert_p = false;
1045 break;
1047 if (conv_p && !DECL_CONV_FN_P (m))
1048 break;
1049 if (DECL_NAME (m) == DECL_NAME (method))
1051 insert_p = false;
1052 break;
1054 if (complete_p
1055 && !DECL_CONV_FN_P (m)
1056 && DECL_NAME (m) > DECL_NAME (method))
1057 break;
1060 current_fns = insert_p ? NULL_TREE : (*method_vec)[slot];
1062 /* Check to see if we've already got this method. */
1063 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1065 tree fn = OVL_CURRENT (fns);
1066 tree fn_type;
1067 tree method_type;
1068 tree parms1;
1069 tree parms2;
1071 if (TREE_CODE (fn) != TREE_CODE (method))
1072 continue;
1074 /* [over.load] Member function declarations with the
1075 same name and the same parameter types cannot be
1076 overloaded if any of them is a static member
1077 function declaration.
1079 [over.load] Member function declarations with the same name and
1080 the same parameter-type-list as well as member function template
1081 declarations with the same name, the same parameter-type-list, and
1082 the same template parameter lists cannot be overloaded if any of
1083 them, but not all, have a ref-qualifier.
1085 [namespace.udecl] When a using-declaration brings names
1086 from a base class into a derived class scope, member
1087 functions in the derived class override and/or hide member
1088 functions with the same name and parameter types in a base
1089 class (rather than conflicting). */
1090 fn_type = TREE_TYPE (fn);
1091 method_type = TREE_TYPE (method);
1092 parms1 = TYPE_ARG_TYPES (fn_type);
1093 parms2 = TYPE_ARG_TYPES (method_type);
1095 /* Compare the quals on the 'this' parm. Don't compare
1096 the whole types, as used functions are treated as
1097 coming from the using class in overload resolution. */
1098 if (! DECL_STATIC_FUNCTION_P (fn)
1099 && ! DECL_STATIC_FUNCTION_P (method)
1100 /* Either both or neither need to be ref-qualified for
1101 differing quals to allow overloading. */
1102 && (FUNCTION_REF_QUALIFIED (fn_type)
1103 == FUNCTION_REF_QUALIFIED (method_type))
1104 && (type_memfn_quals (fn_type) != type_memfn_quals (method_type)
1105 || type_memfn_rqual (fn_type) != type_memfn_rqual (method_type)))
1106 continue;
1108 /* For templates, the return type and template parameters
1109 must be identical. */
1110 if (TREE_CODE (fn) == TEMPLATE_DECL
1111 && (!same_type_p (TREE_TYPE (fn_type),
1112 TREE_TYPE (method_type))
1113 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1114 DECL_TEMPLATE_PARMS (method))))
1115 continue;
1117 if (! DECL_STATIC_FUNCTION_P (fn))
1118 parms1 = TREE_CHAIN (parms1);
1119 if (! DECL_STATIC_FUNCTION_P (method))
1120 parms2 = TREE_CHAIN (parms2);
1122 if (compparms (parms1, parms2)
1123 && (!DECL_CONV_FN_P (fn)
1124 || same_type_p (TREE_TYPE (fn_type),
1125 TREE_TYPE (method_type))))
1127 /* For function versions, their parms and types match
1128 but they are not duplicates. Record function versions
1129 as and when they are found. extern "C" functions are
1130 not treated as versions. */
1131 if (TREE_CODE (fn) == FUNCTION_DECL
1132 && TREE_CODE (method) == FUNCTION_DECL
1133 && !DECL_EXTERN_C_P (fn)
1134 && !DECL_EXTERN_C_P (method)
1135 && targetm.target_option.function_versions (fn, method))
1137 /* Mark functions as versions if necessary. Modify the mangled
1138 decl name if necessary. */
1139 if (!DECL_FUNCTION_VERSIONED (fn))
1141 DECL_FUNCTION_VERSIONED (fn) = 1;
1142 if (DECL_ASSEMBLER_NAME_SET_P (fn))
1143 mangle_decl (fn);
1145 if (!DECL_FUNCTION_VERSIONED (method))
1147 DECL_FUNCTION_VERSIONED (method) = 1;
1148 if (DECL_ASSEMBLER_NAME_SET_P (method))
1149 mangle_decl (method);
1151 record_function_versions (fn, method);
1152 continue;
1154 if (DECL_INHERITED_CTOR_BASE (method))
1156 if (DECL_INHERITED_CTOR_BASE (fn))
1158 error_at (DECL_SOURCE_LOCATION (method),
1159 "%q#D inherited from %qT", method,
1160 DECL_INHERITED_CTOR_BASE (method));
1161 error_at (DECL_SOURCE_LOCATION (fn),
1162 "conflicts with version inherited from %qT",
1163 DECL_INHERITED_CTOR_BASE (fn));
1165 /* Otherwise defer to the other function. */
1166 return false;
1168 if (using_decl)
1170 if (DECL_CONTEXT (fn) == type)
1171 /* Defer to the local function. */
1172 return false;
1174 else
1176 error ("%q+#D cannot be overloaded", method);
1177 error ("with %q+#D", fn);
1180 /* We don't call duplicate_decls here to merge the
1181 declarations because that will confuse things if the
1182 methods have inline definitions. In particular, we
1183 will crash while processing the definitions. */
1184 return false;
1188 /* A class should never have more than one destructor. */
1189 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1190 return false;
1192 /* Add the new binding. */
1193 if (using_decl)
1195 overload = ovl_cons (method, current_fns);
1196 OVL_USED (overload) = true;
1198 else
1199 overload = build_overload (method, current_fns);
1201 if (conv_p)
1202 TYPE_HAS_CONVERSION (type) = 1;
1203 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1204 push_class_level_binding (DECL_NAME (method), overload);
1206 if (insert_p)
1208 bool reallocated;
1210 /* We only expect to add few methods in the COMPLETE_P case, so
1211 just make room for one more method in that case. */
1212 if (complete_p)
1213 reallocated = vec_safe_reserve_exact (method_vec, 1);
1214 else
1215 reallocated = vec_safe_reserve (method_vec, 1);
1216 if (reallocated)
1217 CLASSTYPE_METHOD_VEC (type) = method_vec;
1218 if (slot == method_vec->length ())
1219 method_vec->quick_push (overload);
1220 else
1221 method_vec->quick_insert (slot, overload);
1223 else
1224 /* Replace the current slot. */
1225 (*method_vec)[slot] = overload;
1226 return true;
1229 /* Subroutines of finish_struct. */
1231 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1232 legit, otherwise return 0. */
1234 static int
1235 alter_access (tree t, tree fdecl, tree access)
1237 tree elem;
1239 if (!DECL_LANG_SPECIFIC (fdecl))
1240 retrofit_lang_decl (fdecl);
1242 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1244 elem = purpose_member (t, DECL_ACCESS (fdecl));
1245 if (elem)
1247 if (TREE_VALUE (elem) != access)
1249 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1250 error ("conflicting access specifications for method"
1251 " %q+D, ignored", TREE_TYPE (fdecl));
1252 else
1253 error ("conflicting access specifications for field %qE, ignored",
1254 DECL_NAME (fdecl));
1256 else
1258 /* They're changing the access to the same thing they changed
1259 it to before. That's OK. */
1263 else
1265 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl,
1266 tf_warning_or_error);
1267 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1268 return 1;
1270 return 0;
1273 /* Process the USING_DECL, which is a member of T. */
1275 static void
1276 handle_using_decl (tree using_decl, tree t)
1278 tree decl = USING_DECL_DECLS (using_decl);
1279 tree name = DECL_NAME (using_decl);
1280 tree access
1281 = TREE_PRIVATE (using_decl) ? access_private_node
1282 : TREE_PROTECTED (using_decl) ? access_protected_node
1283 : access_public_node;
1284 tree flist = NULL_TREE;
1285 tree old_value;
1287 gcc_assert (!processing_template_decl && decl);
1289 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false,
1290 tf_warning_or_error);
1291 if (old_value)
1293 if (is_overloaded_fn (old_value))
1294 old_value = OVL_CURRENT (old_value);
1296 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1297 /* OK */;
1298 else
1299 old_value = NULL_TREE;
1302 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1304 if (is_overloaded_fn (decl))
1305 flist = decl;
1307 if (! old_value)
1309 else if (is_overloaded_fn (old_value))
1311 if (flist)
1312 /* It's OK to use functions from a base when there are functions with
1313 the same name already present in the current class. */;
1314 else
1316 error ("%q+D invalid in %q#T", using_decl, t);
1317 error (" because of local method %q+#D with same name",
1318 OVL_CURRENT (old_value));
1319 return;
1322 else if (!DECL_ARTIFICIAL (old_value))
1324 error ("%q+D invalid in %q#T", using_decl, t);
1325 error (" because of local member %q+#D with same name", old_value);
1326 return;
1329 /* Make type T see field decl FDECL with access ACCESS. */
1330 if (flist)
1331 for (; flist; flist = OVL_NEXT (flist))
1333 add_method (t, OVL_CURRENT (flist), using_decl);
1334 alter_access (t, OVL_CURRENT (flist), access);
1336 else
1337 alter_access (t, decl, access);
1340 /* walk_tree callback for check_abi_tags: if the type at *TP involves any
1341 types with abi tags, add the corresponding identifiers to the VEC in
1342 *DATA and set IDENTIFIER_MARKED. */
1344 struct abi_tag_data
1346 tree t;
1347 tree subob;
1348 // error_mark_node to get diagnostics; otherwise collect missing tags here
1349 tree tags;
1352 static tree
1353 find_abi_tags_r (tree *tp, int *walk_subtrees, void *data)
1355 if (!OVERLOAD_TYPE_P (*tp))
1356 return NULL_TREE;
1358 /* walk_tree shouldn't be walking into any subtrees of a RECORD_TYPE
1359 anyway, but let's make sure of it. */
1360 *walk_subtrees = false;
1362 if (tree attributes = lookup_attribute ("abi_tag", TYPE_ATTRIBUTES (*tp)))
1364 struct abi_tag_data *p = static_cast<struct abi_tag_data*>(data);
1365 for (tree list = TREE_VALUE (attributes); list;
1366 list = TREE_CHAIN (list))
1368 tree tag = TREE_VALUE (list);
1369 tree id = get_identifier (TREE_STRING_POINTER (tag));
1370 if (!IDENTIFIER_MARKED (id))
1372 if (p->tags != error_mark_node)
1374 /* We're collecting tags from template arguments. */
1375 tree str = build_string (IDENTIFIER_LENGTH (id),
1376 IDENTIFIER_POINTER (id));
1377 p->tags = tree_cons (NULL_TREE, str, p->tags);
1378 ABI_TAG_IMPLICIT (p->tags) = true;
1380 /* Don't inherit this tag multiple times. */
1381 IDENTIFIER_MARKED (id) = true;
1384 /* Otherwise we're diagnosing missing tags. */
1385 else if (TYPE_P (p->subob))
1387 warning (OPT_Wabi_tag, "%qT does not have the %E abi tag "
1388 "that base %qT has", p->t, tag, p->subob);
1389 inform (location_of (p->subob), "%qT declared here",
1390 p->subob);
1392 else
1394 warning (OPT_Wabi_tag, "%qT does not have the %E abi tag "
1395 "that %qT (used in the type of %qD) has",
1396 p->t, tag, *tp, p->subob);
1397 inform (location_of (p->subob), "%qD declared here",
1398 p->subob);
1399 inform (location_of (*tp), "%qT declared here", *tp);
1404 return NULL_TREE;
1407 /* Set IDENTIFIER_MARKED on all the ABI tags on T and its (transitively
1408 complete) template arguments. */
1410 static void
1411 mark_type_abi_tags (tree t, bool val)
1413 tree attributes = lookup_attribute ("abi_tag", TYPE_ATTRIBUTES (t));
1414 if (attributes)
1416 for (tree list = TREE_VALUE (attributes); list;
1417 list = TREE_CHAIN (list))
1419 tree tag = TREE_VALUE (list);
1420 tree id = get_identifier (TREE_STRING_POINTER (tag));
1421 IDENTIFIER_MARKED (id) = val;
1426 /* Check that class T has all the abi tags that subobject SUBOB has, or
1427 warn if not. */
1429 static void
1430 check_abi_tags (tree t, tree subob)
1432 mark_type_abi_tags (t, true);
1434 tree subtype = TYPE_P (subob) ? subob : TREE_TYPE (subob);
1435 struct abi_tag_data data = { t, subob, error_mark_node };
1437 cp_walk_tree_without_duplicates (&subtype, find_abi_tags_r, &data);
1439 mark_type_abi_tags (t, false);
1442 void
1443 inherit_targ_abi_tags (tree t)
1445 if (CLASSTYPE_TEMPLATE_INFO (t) == NULL_TREE)
1446 return;
1448 mark_type_abi_tags (t, true);
1450 tree args = CLASSTYPE_TI_ARGS (t);
1451 struct abi_tag_data data = { t, NULL_TREE, NULL_TREE };
1452 for (int i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
1454 tree level = TMPL_ARGS_LEVEL (args, i+1);
1455 for (int j = 0; j < TREE_VEC_LENGTH (level); ++j)
1457 tree arg = TREE_VEC_ELT (level, j);
1458 data.subob = arg;
1459 cp_walk_tree_without_duplicates (&arg, find_abi_tags_r, &data);
1463 // If we found some tags on our template arguments, add them to our
1464 // abi_tag attribute.
1465 if (data.tags)
1467 tree attr = lookup_attribute ("abi_tag", TYPE_ATTRIBUTES (t));
1468 if (attr)
1469 TREE_VALUE (attr) = chainon (data.tags, TREE_VALUE (attr));
1470 else
1471 TYPE_ATTRIBUTES (t)
1472 = tree_cons (get_identifier ("abi_tag"), data.tags,
1473 TYPE_ATTRIBUTES (t));
1476 mark_type_abi_tags (t, false);
1479 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1480 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1481 properties of the bases. */
1483 static void
1484 check_bases (tree t,
1485 int* cant_have_const_ctor_p,
1486 int* no_const_asn_ref_p)
1488 int i;
1489 bool seen_non_virtual_nearly_empty_base_p = 0;
1490 int seen_tm_mask = 0;
1491 tree base_binfo;
1492 tree binfo;
1493 tree field = NULL_TREE;
1495 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1496 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
1497 if (TREE_CODE (field) == FIELD_DECL)
1498 break;
1500 for (binfo = TYPE_BINFO (t), i = 0;
1501 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1503 tree basetype = TREE_TYPE (base_binfo);
1505 gcc_assert (COMPLETE_TYPE_P (basetype));
1507 if (CLASSTYPE_FINAL (basetype))
1508 error ("cannot derive from %<final%> base %qT in derived type %qT",
1509 basetype, t);
1511 /* If any base class is non-literal, so is the derived class. */
1512 if (!CLASSTYPE_LITERAL_P (basetype))
1513 CLASSTYPE_LITERAL_P (t) = false;
1515 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1516 here because the case of virtual functions but non-virtual
1517 dtor is handled in finish_struct_1. */
1518 if (!TYPE_POLYMORPHIC_P (basetype))
1519 warning (OPT_Weffc__,
1520 "base class %q#T has a non-virtual destructor", basetype);
1522 /* If the base class doesn't have copy constructors or
1523 assignment operators that take const references, then the
1524 derived class cannot have such a member automatically
1525 generated. */
1526 if (TYPE_HAS_COPY_CTOR (basetype)
1527 && ! TYPE_HAS_CONST_COPY_CTOR (basetype))
1528 *cant_have_const_ctor_p = 1;
1529 if (TYPE_HAS_COPY_ASSIGN (basetype)
1530 && !TYPE_HAS_CONST_COPY_ASSIGN (basetype))
1531 *no_const_asn_ref_p = 1;
1533 if (BINFO_VIRTUAL_P (base_binfo))
1534 /* A virtual base does not effect nearly emptiness. */
1536 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1538 if (seen_non_virtual_nearly_empty_base_p)
1539 /* And if there is more than one nearly empty base, then the
1540 derived class is not nearly empty either. */
1541 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1542 else
1543 /* Remember we've seen one. */
1544 seen_non_virtual_nearly_empty_base_p = 1;
1546 else if (!is_empty_class (basetype))
1547 /* If the base class is not empty or nearly empty, then this
1548 class cannot be nearly empty. */
1549 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1551 /* A lot of properties from the bases also apply to the derived
1552 class. */
1553 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1554 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1555 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1556 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
1557 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (basetype)
1558 || !TYPE_HAS_COPY_ASSIGN (basetype));
1559 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (basetype)
1560 || !TYPE_HAS_COPY_CTOR (basetype));
1561 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t)
1562 |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (basetype);
1563 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (basetype);
1564 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1565 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1566 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1567 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
1568 || TYPE_HAS_COMPLEX_DFLT (basetype));
1569 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT
1570 (t, CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
1571 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (basetype));
1572 SET_CLASSTYPE_REF_FIELDS_NEED_INIT
1573 (t, CLASSTYPE_REF_FIELDS_NEED_INIT (t)
1574 | CLASSTYPE_REF_FIELDS_NEED_INIT (basetype));
1576 /* A standard-layout class is a class that:
1578 * has no non-standard-layout base classes, */
1579 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1580 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1582 tree basefield;
1583 /* ...has no base classes of the same type as the first non-static
1584 data member... */
1585 if (field && DECL_CONTEXT (field) == t
1586 && (same_type_ignoring_top_level_qualifiers_p
1587 (TREE_TYPE (field), basetype)))
1588 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1589 else
1590 /* ...either has no non-static data members in the most-derived
1591 class and at most one base class with non-static data
1592 members, or has no base classes with non-static data
1593 members */
1594 for (basefield = TYPE_FIELDS (basetype); basefield;
1595 basefield = DECL_CHAIN (basefield))
1596 if (TREE_CODE (basefield) == FIELD_DECL)
1598 if (field)
1599 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1600 else
1601 field = basefield;
1602 break;
1606 /* Don't bother collecting tm attributes if transactional memory
1607 support is not enabled. */
1608 if (flag_tm)
1610 tree tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (basetype));
1611 if (tm_attr)
1612 seen_tm_mask |= tm_attr_to_mask (tm_attr);
1615 check_abi_tags (t, basetype);
1618 /* If one of the base classes had TM attributes, and the current class
1619 doesn't define its own, then the current class inherits one. */
1620 if (seen_tm_mask && !find_tm_attribute (TYPE_ATTRIBUTES (t)))
1622 tree tm_attr = tm_mask_to_attr (seen_tm_mask & -seen_tm_mask);
1623 TYPE_ATTRIBUTES (t) = tree_cons (tm_attr, NULL, TYPE_ATTRIBUTES (t));
1627 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1628 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1629 that have had a nearly-empty virtual primary base stolen by some
1630 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1631 T. */
1633 static void
1634 determine_primary_bases (tree t)
1636 unsigned i;
1637 tree primary = NULL_TREE;
1638 tree type_binfo = TYPE_BINFO (t);
1639 tree base_binfo;
1641 /* Determine the primary bases of our bases. */
1642 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1643 base_binfo = TREE_CHAIN (base_binfo))
1645 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1647 /* See if we're the non-virtual primary of our inheritance
1648 chain. */
1649 if (!BINFO_VIRTUAL_P (base_binfo))
1651 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1652 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1654 if (parent_primary
1655 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1656 BINFO_TYPE (parent_primary)))
1657 /* We are the primary binfo. */
1658 BINFO_PRIMARY_P (base_binfo) = 1;
1660 /* Determine if we have a virtual primary base, and mark it so.
1662 if (primary && BINFO_VIRTUAL_P (primary))
1664 tree this_primary = copied_binfo (primary, base_binfo);
1666 if (BINFO_PRIMARY_P (this_primary))
1667 /* Someone already claimed this base. */
1668 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1669 else
1671 tree delta;
1673 BINFO_PRIMARY_P (this_primary) = 1;
1674 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1676 /* A virtual binfo might have been copied from within
1677 another hierarchy. As we're about to use it as a
1678 primary base, make sure the offsets match. */
1679 delta = size_diffop_loc (input_location,
1680 convert (ssizetype,
1681 BINFO_OFFSET (base_binfo)),
1682 convert (ssizetype,
1683 BINFO_OFFSET (this_primary)));
1685 propagate_binfo_offsets (this_primary, delta);
1690 /* First look for a dynamic direct non-virtual base. */
1691 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1693 tree basetype = BINFO_TYPE (base_binfo);
1695 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1697 primary = base_binfo;
1698 goto found;
1702 /* A "nearly-empty" virtual base class can be the primary base
1703 class, if no non-virtual polymorphic base can be found. Look for
1704 a nearly-empty virtual dynamic base that is not already a primary
1705 base of something in the hierarchy. If there is no such base,
1706 just pick the first nearly-empty virtual base. */
1708 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1709 base_binfo = TREE_CHAIN (base_binfo))
1710 if (BINFO_VIRTUAL_P (base_binfo)
1711 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1713 if (!BINFO_PRIMARY_P (base_binfo))
1715 /* Found one that is not primary. */
1716 primary = base_binfo;
1717 goto found;
1719 else if (!primary)
1720 /* Remember the first candidate. */
1721 primary = base_binfo;
1724 found:
1725 /* If we've got a primary base, use it. */
1726 if (primary)
1728 tree basetype = BINFO_TYPE (primary);
1730 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1731 if (BINFO_PRIMARY_P (primary))
1732 /* We are stealing a primary base. */
1733 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1734 BINFO_PRIMARY_P (primary) = 1;
1735 if (BINFO_VIRTUAL_P (primary))
1737 tree delta;
1739 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1740 /* A virtual binfo might have been copied from within
1741 another hierarchy. As we're about to use it as a primary
1742 base, make sure the offsets match. */
1743 delta = size_diffop_loc (input_location, ssize_int (0),
1744 convert (ssizetype, BINFO_OFFSET (primary)));
1746 propagate_binfo_offsets (primary, delta);
1749 primary = TYPE_BINFO (basetype);
1751 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1752 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1753 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1757 /* Update the variant types of T. */
1759 void
1760 fixup_type_variants (tree t)
1762 tree variants;
1764 if (!t)
1765 return;
1767 for (variants = TYPE_NEXT_VARIANT (t);
1768 variants;
1769 variants = TYPE_NEXT_VARIANT (variants))
1771 /* These fields are in the _TYPE part of the node, not in
1772 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1773 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1774 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1775 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1776 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1778 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1780 TYPE_BINFO (variants) = TYPE_BINFO (t);
1782 /* Copy whatever these are holding today. */
1783 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1784 TYPE_METHODS (variants) = TYPE_METHODS (t);
1785 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1789 /* Early variant fixups: we apply attributes at the beginning of the class
1790 definition, and we need to fix up any variants that have already been
1791 made via elaborated-type-specifier so that check_qualified_type works. */
1793 void
1794 fixup_attribute_variants (tree t)
1796 tree variants;
1798 if (!t)
1799 return;
1801 for (variants = TYPE_NEXT_VARIANT (t);
1802 variants;
1803 variants = TYPE_NEXT_VARIANT (variants))
1805 /* These are the two fields that check_qualified_type looks at and
1806 are affected by attributes. */
1807 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1808 TYPE_ALIGN (variants) = TYPE_ALIGN (t);
1812 /* Set memoizing fields and bits of T (and its variants) for later
1813 use. */
1815 static void
1816 finish_struct_bits (tree t)
1818 /* Fix up variants (if any). */
1819 fixup_type_variants (t);
1821 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1822 /* For a class w/o baseclasses, 'finish_struct' has set
1823 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1824 Similarly for a class whose base classes do not have vtables.
1825 When neither of these is true, we might have removed abstract
1826 virtuals (by providing a definition), added some (by declaring
1827 new ones), or redeclared ones from a base class. We need to
1828 recalculate what's really an abstract virtual at this point (by
1829 looking in the vtables). */
1830 get_pure_virtuals (t);
1832 /* If this type has a copy constructor or a destructor, force its
1833 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1834 nonzero. This will cause it to be passed by invisible reference
1835 and prevent it from being returned in a register. */
1836 if (type_has_nontrivial_copy_init (t)
1837 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1839 tree variants;
1840 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1841 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1843 SET_TYPE_MODE (variants, BLKmode);
1844 TREE_ADDRESSABLE (variants) = 1;
1849 /* Issue warnings about T having private constructors, but no friends,
1850 and so forth.
1852 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1853 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1854 non-private static member functions. */
1856 static void
1857 maybe_warn_about_overly_private_class (tree t)
1859 int has_member_fn = 0;
1860 int has_nonprivate_method = 0;
1861 tree fn;
1863 if (!warn_ctor_dtor_privacy
1864 /* If the class has friends, those entities might create and
1865 access instances, so we should not warn. */
1866 || (CLASSTYPE_FRIEND_CLASSES (t)
1867 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1868 /* We will have warned when the template was declared; there's
1869 no need to warn on every instantiation. */
1870 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1871 /* There's no reason to even consider warning about this
1872 class. */
1873 return;
1875 /* We only issue one warning, if more than one applies, because
1876 otherwise, on code like:
1878 class A {
1879 // Oops - forgot `public:'
1880 A();
1881 A(const A&);
1882 ~A();
1885 we warn several times about essentially the same problem. */
1887 /* Check to see if all (non-constructor, non-destructor) member
1888 functions are private. (Since there are no friends or
1889 non-private statics, we can't ever call any of the private member
1890 functions.) */
1891 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
1892 /* We're not interested in compiler-generated methods; they don't
1893 provide any way to call private members. */
1894 if (!DECL_ARTIFICIAL (fn))
1896 if (!TREE_PRIVATE (fn))
1898 if (DECL_STATIC_FUNCTION_P (fn))
1899 /* A non-private static member function is just like a
1900 friend; it can create and invoke private member
1901 functions, and be accessed without a class
1902 instance. */
1903 return;
1905 has_nonprivate_method = 1;
1906 /* Keep searching for a static member function. */
1908 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1909 has_member_fn = 1;
1912 if (!has_nonprivate_method && has_member_fn)
1914 /* There are no non-private methods, and there's at least one
1915 private member function that isn't a constructor or
1916 destructor. (If all the private members are
1917 constructors/destructors we want to use the code below that
1918 issues error messages specifically referring to
1919 constructors/destructors.) */
1920 unsigned i;
1921 tree binfo = TYPE_BINFO (t);
1923 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1924 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1926 has_nonprivate_method = 1;
1927 break;
1929 if (!has_nonprivate_method)
1931 warning (OPT_Wctor_dtor_privacy,
1932 "all member functions in class %qT are private", t);
1933 return;
1937 /* Even if some of the member functions are non-private, the class
1938 won't be useful for much if all the constructors or destructors
1939 are private: such an object can never be created or destroyed. */
1940 fn = CLASSTYPE_DESTRUCTORS (t);
1941 if (fn && TREE_PRIVATE (fn))
1943 warning (OPT_Wctor_dtor_privacy,
1944 "%q#T only defines a private destructor and has no friends",
1946 return;
1949 /* Warn about classes that have private constructors and no friends. */
1950 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1951 /* Implicitly generated constructors are always public. */
1952 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1953 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1955 int nonprivate_ctor = 0;
1957 /* If a non-template class does not define a copy
1958 constructor, one is defined for it, enabling it to avoid
1959 this warning. For a template class, this does not
1960 happen, and so we would normally get a warning on:
1962 template <class T> class C { private: C(); };
1964 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1965 complete non-template or fully instantiated classes have this
1966 flag set. */
1967 if (!TYPE_HAS_COPY_CTOR (t))
1968 nonprivate_ctor = 1;
1969 else
1970 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1972 tree ctor = OVL_CURRENT (fn);
1973 /* Ideally, we wouldn't count copy constructors (or, in
1974 fact, any constructor that takes an argument of the
1975 class type as a parameter) because such things cannot
1976 be used to construct an instance of the class unless
1977 you already have one. But, for now at least, we're
1978 more generous. */
1979 if (! TREE_PRIVATE (ctor))
1981 nonprivate_ctor = 1;
1982 break;
1986 if (nonprivate_ctor == 0)
1988 warning (OPT_Wctor_dtor_privacy,
1989 "%q#T only defines private constructors and has no friends",
1991 return;
1996 static struct {
1997 gt_pointer_operator new_value;
1998 void *cookie;
1999 } resort_data;
2001 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
2003 static int
2004 method_name_cmp (const void* m1_p, const void* m2_p)
2006 const tree *const m1 = (const tree *) m1_p;
2007 const tree *const m2 = (const tree *) m2_p;
2009 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
2010 return 0;
2011 if (*m1 == NULL_TREE)
2012 return -1;
2013 if (*m2 == NULL_TREE)
2014 return 1;
2015 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
2016 return -1;
2017 return 1;
2020 /* This routine compares two fields like method_name_cmp but using the
2021 pointer operator in resort_field_decl_data. */
2023 static int
2024 resort_method_name_cmp (const void* m1_p, const void* m2_p)
2026 const tree *const m1 = (const tree *) m1_p;
2027 const tree *const m2 = (const tree *) m2_p;
2028 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
2029 return 0;
2030 if (*m1 == NULL_TREE)
2031 return -1;
2032 if (*m2 == NULL_TREE)
2033 return 1;
2035 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
2036 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
2037 resort_data.new_value (&d1, resort_data.cookie);
2038 resort_data.new_value (&d2, resort_data.cookie);
2039 if (d1 < d2)
2040 return -1;
2042 return 1;
2045 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
2047 void
2048 resort_type_method_vec (void* obj,
2049 void* /*orig_obj*/,
2050 gt_pointer_operator new_value,
2051 void* cookie)
2053 vec<tree, va_gc> *method_vec = (vec<tree, va_gc> *) obj;
2054 int len = vec_safe_length (method_vec);
2055 size_t slot;
2056 tree fn;
2058 /* The type conversion ops have to live at the front of the vec, so we
2059 can't sort them. */
2060 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
2061 vec_safe_iterate (method_vec, slot, &fn);
2062 ++slot)
2063 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
2064 break;
2066 if (len - slot > 1)
2068 resort_data.new_value = new_value;
2069 resort_data.cookie = cookie;
2070 qsort (method_vec->address () + slot, len - slot, sizeof (tree),
2071 resort_method_name_cmp);
2075 /* Warn about duplicate methods in fn_fields.
2077 Sort methods that are not special (i.e., constructors, destructors,
2078 and type conversion operators) so that we can find them faster in
2079 search. */
2081 static void
2082 finish_struct_methods (tree t)
2084 tree fn_fields;
2085 vec<tree, va_gc> *method_vec;
2086 int slot, len;
2088 method_vec = CLASSTYPE_METHOD_VEC (t);
2089 if (!method_vec)
2090 return;
2092 len = method_vec->length ();
2094 /* Clear DECL_IN_AGGR_P for all functions. */
2095 for (fn_fields = TYPE_METHODS (t); fn_fields;
2096 fn_fields = DECL_CHAIN (fn_fields))
2097 DECL_IN_AGGR_P (fn_fields) = 0;
2099 /* Issue warnings about private constructors and such. If there are
2100 no methods, then some public defaults are generated. */
2101 maybe_warn_about_overly_private_class (t);
2103 /* The type conversion ops have to live at the front of the vec, so we
2104 can't sort them. */
2105 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
2106 method_vec->iterate (slot, &fn_fields);
2107 ++slot)
2108 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
2109 break;
2110 if (len - slot > 1)
2111 qsort (method_vec->address () + slot,
2112 len-slot, sizeof (tree), method_name_cmp);
2115 /* Make BINFO's vtable have N entries, including RTTI entries,
2116 vbase and vcall offsets, etc. Set its type and call the back end
2117 to lay it out. */
2119 static void
2120 layout_vtable_decl (tree binfo, int n)
2122 tree atype;
2123 tree vtable;
2125 atype = build_array_of_n_type (vtable_entry_type, n);
2126 layout_type (atype);
2128 /* We may have to grow the vtable. */
2129 vtable = get_vtbl_decl_for_binfo (binfo);
2130 if (!same_type_p (TREE_TYPE (vtable), atype))
2132 TREE_TYPE (vtable) = atype;
2133 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
2134 layout_decl (vtable, 0);
2138 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
2139 have the same signature. */
2142 same_signature_p (const_tree fndecl, const_tree base_fndecl)
2144 /* One destructor overrides another if they are the same kind of
2145 destructor. */
2146 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
2147 && special_function_p (base_fndecl) == special_function_p (fndecl))
2148 return 1;
2149 /* But a non-destructor never overrides a destructor, nor vice
2150 versa, nor do different kinds of destructors override
2151 one-another. For example, a complete object destructor does not
2152 override a deleting destructor. */
2153 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
2154 return 0;
2156 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
2157 || (DECL_CONV_FN_P (fndecl)
2158 && DECL_CONV_FN_P (base_fndecl)
2159 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
2160 DECL_CONV_FN_TYPE (base_fndecl))))
2162 tree fntype = TREE_TYPE (fndecl);
2163 tree base_fntype = TREE_TYPE (base_fndecl);
2164 if (type_memfn_quals (fntype) == type_memfn_quals (base_fntype)
2165 && type_memfn_rqual (fntype) == type_memfn_rqual (base_fntype)
2166 && compparms (FUNCTION_FIRST_USER_PARMTYPE (fndecl),
2167 FUNCTION_FIRST_USER_PARMTYPE (base_fndecl)))
2168 return 1;
2170 return 0;
2173 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
2174 subobject. */
2176 static bool
2177 base_derived_from (tree derived, tree base)
2179 tree probe;
2181 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
2183 if (probe == derived)
2184 return true;
2185 else if (BINFO_VIRTUAL_P (probe))
2186 /* If we meet a virtual base, we can't follow the inheritance
2187 any more. See if the complete type of DERIVED contains
2188 such a virtual base. */
2189 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
2190 != NULL_TREE);
2192 return false;
2195 typedef struct find_final_overrider_data_s {
2196 /* The function for which we are trying to find a final overrider. */
2197 tree fn;
2198 /* The base class in which the function was declared. */
2199 tree declaring_base;
2200 /* The candidate overriders. */
2201 tree candidates;
2202 /* Path to most derived. */
2203 vec<tree> path;
2204 } find_final_overrider_data;
2206 /* Add the overrider along the current path to FFOD->CANDIDATES.
2207 Returns true if an overrider was found; false otherwise. */
2209 static bool
2210 dfs_find_final_overrider_1 (tree binfo,
2211 find_final_overrider_data *ffod,
2212 unsigned depth)
2214 tree method;
2216 /* If BINFO is not the most derived type, try a more derived class.
2217 A definition there will overrider a definition here. */
2218 if (depth)
2220 depth--;
2221 if (dfs_find_final_overrider_1
2222 (ffod->path[depth], ffod, depth))
2223 return true;
2226 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
2227 if (method)
2229 tree *candidate = &ffod->candidates;
2231 /* Remove any candidates overridden by this new function. */
2232 while (*candidate)
2234 /* If *CANDIDATE overrides METHOD, then METHOD
2235 cannot override anything else on the list. */
2236 if (base_derived_from (TREE_VALUE (*candidate), binfo))
2237 return true;
2238 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
2239 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
2240 *candidate = TREE_CHAIN (*candidate);
2241 else
2242 candidate = &TREE_CHAIN (*candidate);
2245 /* Add the new function. */
2246 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
2247 return true;
2250 return false;
2253 /* Called from find_final_overrider via dfs_walk. */
2255 static tree
2256 dfs_find_final_overrider_pre (tree binfo, void *data)
2258 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
2260 if (binfo == ffod->declaring_base)
2261 dfs_find_final_overrider_1 (binfo, ffod, ffod->path.length ());
2262 ffod->path.safe_push (binfo);
2264 return NULL_TREE;
2267 static tree
2268 dfs_find_final_overrider_post (tree /*binfo*/, void *data)
2270 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
2271 ffod->path.pop ();
2273 return NULL_TREE;
2276 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
2277 FN and whose TREE_VALUE is the binfo for the base where the
2278 overriding occurs. BINFO (in the hierarchy dominated by the binfo
2279 DERIVED) is the base object in which FN is declared. */
2281 static tree
2282 find_final_overrider (tree derived, tree binfo, tree fn)
2284 find_final_overrider_data ffod;
2286 /* Getting this right is a little tricky. This is valid:
2288 struct S { virtual void f (); };
2289 struct T { virtual void f (); };
2290 struct U : public S, public T { };
2292 even though calling `f' in `U' is ambiguous. But,
2294 struct R { virtual void f(); };
2295 struct S : virtual public R { virtual void f (); };
2296 struct T : virtual public R { virtual void f (); };
2297 struct U : public S, public T { };
2299 is not -- there's no way to decide whether to put `S::f' or
2300 `T::f' in the vtable for `R'.
2302 The solution is to look at all paths to BINFO. If we find
2303 different overriders along any two, then there is a problem. */
2304 if (DECL_THUNK_P (fn))
2305 fn = THUNK_TARGET (fn);
2307 /* Determine the depth of the hierarchy. */
2308 ffod.fn = fn;
2309 ffod.declaring_base = binfo;
2310 ffod.candidates = NULL_TREE;
2311 ffod.path.create (30);
2313 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2314 dfs_find_final_overrider_post, &ffod);
2316 ffod.path.release ();
2318 /* If there was no winner, issue an error message. */
2319 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2320 return error_mark_node;
2322 return ffod.candidates;
2325 /* Return the index of the vcall offset for FN when TYPE is used as a
2326 virtual base. */
2328 static tree
2329 get_vcall_index (tree fn, tree type)
2331 vec<tree_pair_s, va_gc> *indices = CLASSTYPE_VCALL_INDICES (type);
2332 tree_pair_p p;
2333 unsigned ix;
2335 FOR_EACH_VEC_SAFE_ELT (indices, ix, p)
2336 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2337 || same_signature_p (fn, p->purpose))
2338 return p->value;
2340 /* There should always be an appropriate index. */
2341 gcc_unreachable ();
2344 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2345 dominated by T. FN is the old function; VIRTUALS points to the
2346 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2347 of that entry in the list. */
2349 static void
2350 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2351 unsigned ix)
2353 tree b;
2354 tree overrider;
2355 tree delta;
2356 tree virtual_base;
2357 tree first_defn;
2358 tree overrider_fn, overrider_target;
2359 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2360 tree over_return, base_return;
2361 bool lost = false;
2363 /* Find the nearest primary base (possibly binfo itself) which defines
2364 this function; this is the class the caller will convert to when
2365 calling FN through BINFO. */
2366 for (b = binfo; ; b = get_primary_binfo (b))
2368 gcc_assert (b);
2369 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2370 break;
2372 /* The nearest definition is from a lost primary. */
2373 if (BINFO_LOST_PRIMARY_P (b))
2374 lost = true;
2376 first_defn = b;
2378 /* Find the final overrider. */
2379 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2380 if (overrider == error_mark_node)
2382 error ("no unique final overrider for %qD in %qT", target_fn, t);
2383 return;
2385 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2387 /* Check for adjusting covariant return types. */
2388 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2389 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2391 if (POINTER_TYPE_P (over_return)
2392 && TREE_CODE (over_return) == TREE_CODE (base_return)
2393 && CLASS_TYPE_P (TREE_TYPE (over_return))
2394 && CLASS_TYPE_P (TREE_TYPE (base_return))
2395 /* If the overrider is invalid, don't even try. */
2396 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2398 /* If FN is a covariant thunk, we must figure out the adjustment
2399 to the final base FN was converting to. As OVERRIDER_TARGET might
2400 also be converting to the return type of FN, we have to
2401 combine the two conversions here. */
2402 tree fixed_offset, virtual_offset;
2404 over_return = TREE_TYPE (over_return);
2405 base_return = TREE_TYPE (base_return);
2407 if (DECL_THUNK_P (fn))
2409 gcc_assert (DECL_RESULT_THUNK_P (fn));
2410 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2411 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2413 else
2414 fixed_offset = virtual_offset = NULL_TREE;
2416 if (virtual_offset)
2417 /* Find the equivalent binfo within the return type of the
2418 overriding function. We will want the vbase offset from
2419 there. */
2420 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2421 over_return);
2422 else if (!same_type_ignoring_top_level_qualifiers_p
2423 (over_return, base_return))
2425 /* There was no existing virtual thunk (which takes
2426 precedence). So find the binfo of the base function's
2427 return type within the overriding function's return type.
2428 We cannot call lookup base here, because we're inside a
2429 dfs_walk, and will therefore clobber the BINFO_MARKED
2430 flags. Fortunately we know the covariancy is valid (it
2431 has already been checked), so we can just iterate along
2432 the binfos, which have been chained in inheritance graph
2433 order. Of course it is lame that we have to repeat the
2434 search here anyway -- we should really be caching pieces
2435 of the vtable and avoiding this repeated work. */
2436 tree thunk_binfo, base_binfo;
2438 /* Find the base binfo within the overriding function's
2439 return type. We will always find a thunk_binfo, except
2440 when the covariancy is invalid (which we will have
2441 already diagnosed). */
2442 for (base_binfo = TYPE_BINFO (base_return),
2443 thunk_binfo = TYPE_BINFO (over_return);
2444 thunk_binfo;
2445 thunk_binfo = TREE_CHAIN (thunk_binfo))
2446 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2447 BINFO_TYPE (base_binfo)))
2448 break;
2450 /* See if virtual inheritance is involved. */
2451 for (virtual_offset = thunk_binfo;
2452 virtual_offset;
2453 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2454 if (BINFO_VIRTUAL_P (virtual_offset))
2455 break;
2457 if (virtual_offset
2458 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2460 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2462 if (virtual_offset)
2464 /* We convert via virtual base. Adjust the fixed
2465 offset to be from there. */
2466 offset =
2467 size_diffop (offset,
2468 convert (ssizetype,
2469 BINFO_OFFSET (virtual_offset)));
2471 if (fixed_offset)
2472 /* There was an existing fixed offset, this must be
2473 from the base just converted to, and the base the
2474 FN was thunking to. */
2475 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2476 else
2477 fixed_offset = offset;
2481 if (fixed_offset || virtual_offset)
2482 /* Replace the overriding function with a covariant thunk. We
2483 will emit the overriding function in its own slot as
2484 well. */
2485 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2486 fixed_offset, virtual_offset);
2488 else
2489 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2490 !DECL_THUNK_P (fn));
2492 /* If we need a covariant thunk, then we may need to adjust first_defn.
2493 The ABI specifies that the thunks emitted with a function are
2494 determined by which bases the function overrides, so we need to be
2495 sure that we're using a thunk for some overridden base; even if we
2496 know that the necessary this adjustment is zero, there may not be an
2497 appropriate zero-this-adjusment thunk for us to use since thunks for
2498 overriding virtual bases always use the vcall offset.
2500 Furthermore, just choosing any base that overrides this function isn't
2501 quite right, as this slot won't be used for calls through a type that
2502 puts a covariant thunk here. Calling the function through such a type
2503 will use a different slot, and that slot is the one that determines
2504 the thunk emitted for that base.
2506 So, keep looking until we find the base that we're really overriding
2507 in this slot: the nearest primary base that doesn't use a covariant
2508 thunk in this slot. */
2509 if (overrider_target != overrider_fn)
2511 if (BINFO_TYPE (b) == DECL_CONTEXT (overrider_target))
2512 /* We already know that the overrider needs a covariant thunk. */
2513 b = get_primary_binfo (b);
2514 for (; ; b = get_primary_binfo (b))
2516 tree main_binfo = TYPE_BINFO (BINFO_TYPE (b));
2517 tree bv = chain_index (ix, BINFO_VIRTUALS (main_binfo));
2518 if (!DECL_THUNK_P (TREE_VALUE (bv)))
2519 break;
2520 if (BINFO_LOST_PRIMARY_P (b))
2521 lost = true;
2523 first_defn = b;
2526 /* Assume that we will produce a thunk that convert all the way to
2527 the final overrider, and not to an intermediate virtual base. */
2528 virtual_base = NULL_TREE;
2530 /* See if we can convert to an intermediate virtual base first, and then
2531 use the vcall offset located there to finish the conversion. */
2532 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2534 /* If we find the final overrider, then we can stop
2535 walking. */
2536 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2537 BINFO_TYPE (TREE_VALUE (overrider))))
2538 break;
2540 /* If we find a virtual base, and we haven't yet found the
2541 overrider, then there is a virtual base between the
2542 declaring base (first_defn) and the final overrider. */
2543 if (BINFO_VIRTUAL_P (b))
2545 virtual_base = b;
2546 break;
2550 /* Compute the constant adjustment to the `this' pointer. The
2551 `this' pointer, when this function is called, will point at BINFO
2552 (or one of its primary bases, which are at the same offset). */
2553 if (virtual_base)
2554 /* The `this' pointer needs to be adjusted from the declaration to
2555 the nearest virtual base. */
2556 delta = size_diffop_loc (input_location,
2557 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2558 convert (ssizetype, BINFO_OFFSET (first_defn)));
2559 else if (lost)
2560 /* If the nearest definition is in a lost primary, we don't need an
2561 entry in our vtable. Except possibly in a constructor vtable,
2562 if we happen to get our primary back. In that case, the offset
2563 will be zero, as it will be a primary base. */
2564 delta = size_zero_node;
2565 else
2566 /* The `this' pointer needs to be adjusted from pointing to
2567 BINFO to pointing at the base where the final overrider
2568 appears. */
2569 delta = size_diffop_loc (input_location,
2570 convert (ssizetype,
2571 BINFO_OFFSET (TREE_VALUE (overrider))),
2572 convert (ssizetype, BINFO_OFFSET (binfo)));
2574 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2576 if (virtual_base)
2577 BV_VCALL_INDEX (*virtuals)
2578 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2579 else
2580 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2582 BV_LOST_PRIMARY (*virtuals) = lost;
2585 /* Called from modify_all_vtables via dfs_walk. */
2587 static tree
2588 dfs_modify_vtables (tree binfo, void* data)
2590 tree t = (tree) data;
2591 tree virtuals;
2592 tree old_virtuals;
2593 unsigned ix;
2595 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2596 /* A base without a vtable needs no modification, and its bases
2597 are uninteresting. */
2598 return dfs_skip_bases;
2600 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2601 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2602 /* Don't do the primary vtable, if it's new. */
2603 return NULL_TREE;
2605 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2606 /* There's no need to modify the vtable for a non-virtual primary
2607 base; we're not going to use that vtable anyhow. We do still
2608 need to do this for virtual primary bases, as they could become
2609 non-primary in a construction vtable. */
2610 return NULL_TREE;
2612 make_new_vtable (t, binfo);
2614 /* Now, go through each of the virtual functions in the virtual
2615 function table for BINFO. Find the final overrider, and update
2616 the BINFO_VIRTUALS list appropriately. */
2617 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2618 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2619 virtuals;
2620 ix++, virtuals = TREE_CHAIN (virtuals),
2621 old_virtuals = TREE_CHAIN (old_virtuals))
2622 update_vtable_entry_for_fn (t,
2623 binfo,
2624 BV_FN (old_virtuals),
2625 &virtuals, ix);
2627 return NULL_TREE;
2630 /* Update all of the primary and secondary vtables for T. Create new
2631 vtables as required, and initialize their RTTI information. Each
2632 of the functions in VIRTUALS is declared in T and may override a
2633 virtual function from a base class; find and modify the appropriate
2634 entries to point to the overriding functions. Returns a list, in
2635 declaration order, of the virtual functions that are declared in T,
2636 but do not appear in the primary base class vtable, and which
2637 should therefore be appended to the end of the vtable for T. */
2639 static tree
2640 modify_all_vtables (tree t, tree virtuals)
2642 tree binfo = TYPE_BINFO (t);
2643 tree *fnsp;
2645 /* Mangle the vtable name before entering dfs_walk (c++/51884). */
2646 if (TYPE_CONTAINS_VPTR_P (t))
2647 get_vtable_decl (t, false);
2649 /* Update all of the vtables. */
2650 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2652 /* Add virtual functions not already in our primary vtable. These
2653 will be both those introduced by this class, and those overridden
2654 from secondary bases. It does not include virtuals merely
2655 inherited from secondary bases. */
2656 for (fnsp = &virtuals; *fnsp; )
2658 tree fn = TREE_VALUE (*fnsp);
2660 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2661 || DECL_VINDEX (fn) == error_mark_node)
2663 /* We don't need to adjust the `this' pointer when
2664 calling this function. */
2665 BV_DELTA (*fnsp) = integer_zero_node;
2666 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2668 /* This is a function not already in our vtable. Keep it. */
2669 fnsp = &TREE_CHAIN (*fnsp);
2671 else
2672 /* We've already got an entry for this function. Skip it. */
2673 *fnsp = TREE_CHAIN (*fnsp);
2676 return virtuals;
2679 /* Get the base virtual function declarations in T that have the
2680 indicated NAME. */
2682 static tree
2683 get_basefndecls (tree name, tree t)
2685 tree methods;
2686 tree base_fndecls = NULL_TREE;
2687 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2688 int i;
2690 /* Find virtual functions in T with the indicated NAME. */
2691 i = lookup_fnfields_1 (t, name);
2692 if (i != -1)
2693 for (methods = (*CLASSTYPE_METHOD_VEC (t))[i];
2694 methods;
2695 methods = OVL_NEXT (methods))
2697 tree method = OVL_CURRENT (methods);
2699 if (TREE_CODE (method) == FUNCTION_DECL
2700 && DECL_VINDEX (method))
2701 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2704 if (base_fndecls)
2705 return base_fndecls;
2707 for (i = 0; i < n_baseclasses; i++)
2709 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2710 base_fndecls = chainon (get_basefndecls (name, basetype),
2711 base_fndecls);
2714 return base_fndecls;
2717 /* If this declaration supersedes the declaration of
2718 a method declared virtual in the base class, then
2719 mark this field as being virtual as well. */
2721 void
2722 check_for_override (tree decl, tree ctype)
2724 bool overrides_found = false;
2725 if (TREE_CODE (decl) == TEMPLATE_DECL)
2726 /* In [temp.mem] we have:
2728 A specialization of a member function template does not
2729 override a virtual function from a base class. */
2730 return;
2731 if ((DECL_DESTRUCTOR_P (decl)
2732 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2733 || DECL_CONV_FN_P (decl))
2734 && look_for_overrides (ctype, decl)
2735 && !DECL_STATIC_FUNCTION_P (decl))
2736 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2737 the error_mark_node so that we know it is an overriding
2738 function. */
2740 DECL_VINDEX (decl) = decl;
2741 overrides_found = true;
2744 if (DECL_VIRTUAL_P (decl))
2746 if (!DECL_VINDEX (decl))
2747 DECL_VINDEX (decl) = error_mark_node;
2748 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2749 if (DECL_DESTRUCTOR_P (decl))
2750 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (ctype) = true;
2752 else if (DECL_FINAL_P (decl))
2753 error ("%q+#D marked final, but is not virtual", decl);
2754 if (DECL_OVERRIDE_P (decl) && !overrides_found)
2755 error ("%q+#D marked override, but does not override", decl);
2758 /* Warn about hidden virtual functions that are not overridden in t.
2759 We know that constructors and destructors don't apply. */
2761 static void
2762 warn_hidden (tree t)
2764 vec<tree, va_gc> *method_vec = CLASSTYPE_METHOD_VEC (t);
2765 tree fns;
2766 size_t i;
2768 /* We go through each separately named virtual function. */
2769 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2770 vec_safe_iterate (method_vec, i, &fns);
2771 ++i)
2773 tree fn;
2774 tree name;
2775 tree fndecl;
2776 tree base_fndecls;
2777 tree base_binfo;
2778 tree binfo;
2779 int j;
2781 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2782 have the same name. Figure out what name that is. */
2783 name = DECL_NAME (OVL_CURRENT (fns));
2784 /* There are no possibly hidden functions yet. */
2785 base_fndecls = NULL_TREE;
2786 /* Iterate through all of the base classes looking for possibly
2787 hidden functions. */
2788 for (binfo = TYPE_BINFO (t), j = 0;
2789 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2791 tree basetype = BINFO_TYPE (base_binfo);
2792 base_fndecls = chainon (get_basefndecls (name, basetype),
2793 base_fndecls);
2796 /* If there are no functions to hide, continue. */
2797 if (!base_fndecls)
2798 continue;
2800 /* Remove any overridden functions. */
2801 for (fn = fns; fn; fn = OVL_NEXT (fn))
2803 fndecl = OVL_CURRENT (fn);
2804 if (DECL_VINDEX (fndecl))
2806 tree *prev = &base_fndecls;
2808 while (*prev)
2809 /* If the method from the base class has the same
2810 signature as the method from the derived class, it
2811 has been overridden. */
2812 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2813 *prev = TREE_CHAIN (*prev);
2814 else
2815 prev = &TREE_CHAIN (*prev);
2819 /* Now give a warning for all base functions without overriders,
2820 as they are hidden. */
2821 while (base_fndecls)
2823 /* Here we know it is a hider, and no overrider exists. */
2824 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2825 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2826 base_fndecls = TREE_CHAIN (base_fndecls);
2831 /* Recursive helper for finish_struct_anon. */
2833 static void
2834 finish_struct_anon_r (tree field, bool complain)
2836 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2837 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2838 for (; elt; elt = DECL_CHAIN (elt))
2840 /* We're generally only interested in entities the user
2841 declared, but we also find nested classes by noticing
2842 the TYPE_DECL that we create implicitly. You're
2843 allowed to put one anonymous union inside another,
2844 though, so we explicitly tolerate that. We use
2845 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2846 we also allow unnamed types used for defining fields. */
2847 if (DECL_ARTIFICIAL (elt)
2848 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2849 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2850 continue;
2852 if (TREE_CODE (elt) != FIELD_DECL)
2854 /* We already complained about static data members in
2855 finish_static_data_member_decl. */
2856 if (complain && TREE_CODE (elt) != VAR_DECL)
2858 if (is_union)
2859 permerror (input_location,
2860 "%q+#D invalid; an anonymous union can "
2861 "only have non-static data members", elt);
2862 else
2863 permerror (input_location,
2864 "%q+#D invalid; an anonymous struct can "
2865 "only have non-static data members", elt);
2867 continue;
2870 if (complain)
2872 if (TREE_PRIVATE (elt))
2874 if (is_union)
2875 permerror (input_location,
2876 "private member %q+#D in anonymous union", elt);
2877 else
2878 permerror (input_location,
2879 "private member %q+#D in anonymous struct", elt);
2881 else if (TREE_PROTECTED (elt))
2883 if (is_union)
2884 permerror (input_location,
2885 "protected member %q+#D in anonymous union", elt);
2886 else
2887 permerror (input_location,
2888 "protected member %q+#D in anonymous struct", elt);
2892 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2893 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2895 /* Recurse into the anonymous aggregates to handle correctly
2896 access control (c++/24926):
2898 class A {
2899 union {
2900 union {
2901 int i;
2906 int j=A().i; */
2907 if (DECL_NAME (elt) == NULL_TREE
2908 && ANON_AGGR_TYPE_P (TREE_TYPE (elt)))
2909 finish_struct_anon_r (elt, /*complain=*/false);
2913 /* Check for things that are invalid. There are probably plenty of other
2914 things we should check for also. */
2916 static void
2917 finish_struct_anon (tree t)
2919 for (tree field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
2921 if (TREE_STATIC (field))
2922 continue;
2923 if (TREE_CODE (field) != FIELD_DECL)
2924 continue;
2926 if (DECL_NAME (field) == NULL_TREE
2927 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2928 finish_struct_anon_r (field, /*complain=*/true);
2932 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2933 will be used later during class template instantiation.
2934 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2935 a non-static member data (FIELD_DECL), a member function
2936 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2937 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2938 When FRIEND_P is nonzero, T is either a friend class
2939 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2940 (FUNCTION_DECL, TEMPLATE_DECL). */
2942 void
2943 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2945 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2946 if (CLASSTYPE_TEMPLATE_INFO (type))
2947 CLASSTYPE_DECL_LIST (type)
2948 = tree_cons (friend_p ? NULL_TREE : type,
2949 t, CLASSTYPE_DECL_LIST (type));
2952 /* This function is called from declare_virt_assop_and_dtor via
2953 dfs_walk_all.
2955 DATA is a type that direcly or indirectly inherits the base
2956 represented by BINFO. If BINFO contains a virtual assignment [copy
2957 assignment or move assigment] operator or a virtual constructor,
2958 declare that function in DATA if it hasn't been already declared. */
2960 static tree
2961 dfs_declare_virt_assop_and_dtor (tree binfo, void *data)
2963 tree bv, fn, t = (tree)data;
2964 tree opname = ansi_assopname (NOP_EXPR);
2966 gcc_assert (t && CLASS_TYPE_P (t));
2967 gcc_assert (binfo && TREE_CODE (binfo) == TREE_BINFO);
2969 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2970 /* A base without a vtable needs no modification, and its bases
2971 are uninteresting. */
2972 return dfs_skip_bases;
2974 if (BINFO_PRIMARY_P (binfo))
2975 /* If this is a primary base, then we have already looked at the
2976 virtual functions of its vtable. */
2977 return NULL_TREE;
2979 for (bv = BINFO_VIRTUALS (binfo); bv; bv = TREE_CHAIN (bv))
2981 fn = BV_FN (bv);
2983 if (DECL_NAME (fn) == opname)
2985 if (CLASSTYPE_LAZY_COPY_ASSIGN (t))
2986 lazily_declare_fn (sfk_copy_assignment, t);
2987 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
2988 lazily_declare_fn (sfk_move_assignment, t);
2990 else if (DECL_DESTRUCTOR_P (fn)
2991 && CLASSTYPE_LAZY_DESTRUCTOR (t))
2992 lazily_declare_fn (sfk_destructor, t);
2995 return NULL_TREE;
2998 /* If the class type T has a direct or indirect base that contains a
2999 virtual assignment operator or a virtual destructor, declare that
3000 function in T if it hasn't been already declared. */
3002 static void
3003 declare_virt_assop_and_dtor (tree t)
3005 if (!(TYPE_POLYMORPHIC_P (t)
3006 && (CLASSTYPE_LAZY_COPY_ASSIGN (t)
3007 || CLASSTYPE_LAZY_MOVE_ASSIGN (t)
3008 || CLASSTYPE_LAZY_DESTRUCTOR (t))))
3009 return;
3011 dfs_walk_all (TYPE_BINFO (t),
3012 dfs_declare_virt_assop_and_dtor,
3013 NULL, t);
3016 /* Declare the inheriting constructor for class T inherited from base
3017 constructor CTOR with the parameter array PARMS of size NPARMS. */
3019 static void
3020 one_inheriting_sig (tree t, tree ctor, tree *parms, int nparms)
3022 /* We don't declare an inheriting ctor that would be a default,
3023 copy or move ctor for derived or base. */
3024 if (nparms == 0)
3025 return;
3026 if (nparms == 1
3027 && TREE_CODE (parms[0]) == REFERENCE_TYPE)
3029 tree parm = TYPE_MAIN_VARIANT (TREE_TYPE (parms[0]));
3030 if (parm == t || parm == DECL_CONTEXT (ctor))
3031 return;
3034 tree parmlist = void_list_node;
3035 for (int i = nparms - 1; i >= 0; i--)
3036 parmlist = tree_cons (NULL_TREE, parms[i], parmlist);
3037 tree fn = implicitly_declare_fn (sfk_inheriting_constructor,
3038 t, false, ctor, parmlist);
3039 if (add_method (t, fn, NULL_TREE))
3041 DECL_CHAIN (fn) = TYPE_METHODS (t);
3042 TYPE_METHODS (t) = fn;
3046 /* Declare all the inheriting constructors for class T inherited from base
3047 constructor CTOR. */
3049 static void
3050 one_inherited_ctor (tree ctor, tree t)
3052 tree parms = FUNCTION_FIRST_USER_PARMTYPE (ctor);
3054 tree *new_parms = XALLOCAVEC (tree, list_length (parms));
3055 int i = 0;
3056 for (; parms && parms != void_list_node; parms = TREE_CHAIN (parms))
3058 if (TREE_PURPOSE (parms))
3059 one_inheriting_sig (t, ctor, new_parms, i);
3060 new_parms[i++] = TREE_VALUE (parms);
3062 one_inheriting_sig (t, ctor, new_parms, i);
3063 if (parms == NULL_TREE)
3065 warning (OPT_Winherited_variadic_ctor,
3066 "the ellipsis in %qD is not inherited", ctor);
3067 inform (DECL_SOURCE_LOCATION (ctor), "%qD declared here", ctor);
3071 /* Create default constructors, assignment operators, and so forth for
3072 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
3073 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
3074 the class cannot have a default constructor, copy constructor
3075 taking a const reference argument, or an assignment operator taking
3076 a const reference, respectively. */
3078 static void
3079 add_implicitly_declared_members (tree t, tree* access_decls,
3080 int cant_have_const_cctor,
3081 int cant_have_const_assignment)
3083 bool move_ok = false;
3085 if (cxx_dialect >= cxx11 && !CLASSTYPE_DESTRUCTORS (t)
3086 && !TYPE_HAS_COPY_CTOR (t) && !TYPE_HAS_COPY_ASSIGN (t)
3087 && !type_has_move_constructor (t) && !type_has_move_assign (t))
3088 move_ok = true;
3090 /* Destructor. */
3091 if (!CLASSTYPE_DESTRUCTORS (t))
3093 /* In general, we create destructors lazily. */
3094 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
3096 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3097 && TYPE_FOR_JAVA (t))
3098 /* But if this is a Java class, any non-trivial destructor is
3099 invalid, even if compiler-generated. Therefore, if the
3100 destructor is non-trivial we create it now. */
3101 lazily_declare_fn (sfk_destructor, t);
3104 /* [class.ctor]
3106 If there is no user-declared constructor for a class, a default
3107 constructor is implicitly declared. */
3108 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
3110 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
3111 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
3112 if (cxx_dialect >= cxx11)
3113 TYPE_HAS_CONSTEXPR_CTOR (t)
3114 /* This might force the declaration. */
3115 = type_has_constexpr_default_constructor (t);
3118 /* [class.ctor]
3120 If a class definition does not explicitly declare a copy
3121 constructor, one is declared implicitly. */
3122 if (! TYPE_HAS_COPY_CTOR (t) && ! TYPE_FOR_JAVA (t))
3124 TYPE_HAS_COPY_CTOR (t) = 1;
3125 TYPE_HAS_CONST_COPY_CTOR (t) = !cant_have_const_cctor;
3126 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
3127 if (move_ok)
3128 CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
3131 /* If there is no assignment operator, one will be created if and
3132 when it is needed. For now, just record whether or not the type
3133 of the parameter to the assignment operator will be a const or
3134 non-const reference. */
3135 if (!TYPE_HAS_COPY_ASSIGN (t) && !TYPE_FOR_JAVA (t))
3137 TYPE_HAS_COPY_ASSIGN (t) = 1;
3138 TYPE_HAS_CONST_COPY_ASSIGN (t) = !cant_have_const_assignment;
3139 CLASSTYPE_LAZY_COPY_ASSIGN (t) = 1;
3140 if (move_ok)
3141 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 1;
3144 /* We can't be lazy about declaring functions that might override
3145 a virtual function from a base class. */
3146 declare_virt_assop_and_dtor (t);
3148 while (*access_decls)
3150 tree using_decl = TREE_VALUE (*access_decls);
3151 tree decl = USING_DECL_DECLS (using_decl);
3152 if (DECL_NAME (using_decl) == ctor_identifier)
3154 /* declare, then remove the decl */
3155 tree ctor_list = decl;
3156 location_t loc = input_location;
3157 input_location = DECL_SOURCE_LOCATION (using_decl);
3158 if (ctor_list)
3159 for (; ctor_list; ctor_list = OVL_NEXT (ctor_list))
3160 one_inherited_ctor (OVL_CURRENT (ctor_list), t);
3161 *access_decls = TREE_CHAIN (*access_decls);
3162 input_location = loc;
3164 else
3165 access_decls = &TREE_CHAIN (*access_decls);
3169 /* Subroutine of insert_into_classtype_sorted_fields. Recursively
3170 count the number of fields in TYPE, including anonymous union
3171 members. */
3173 static int
3174 count_fields (tree fields)
3176 tree x;
3177 int n_fields = 0;
3178 for (x = fields; x; x = DECL_CHAIN (x))
3180 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
3181 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
3182 else
3183 n_fields += 1;
3185 return n_fields;
3188 /* Subroutine of insert_into_classtype_sorted_fields. Recursively add
3189 all the fields in the TREE_LIST FIELDS to the SORTED_FIELDS_TYPE
3190 elts, starting at offset IDX. */
3192 static int
3193 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
3195 tree x;
3196 for (x = fields; x; x = DECL_CHAIN (x))
3198 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
3199 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
3200 else
3201 field_vec->elts[idx++] = x;
3203 return idx;
3206 /* Add all of the enum values of ENUMTYPE, to the FIELD_VEC elts,
3207 starting at offset IDX. */
3209 static int
3210 add_enum_fields_to_record_type (tree enumtype,
3211 struct sorted_fields_type *field_vec,
3212 int idx)
3214 tree values;
3215 for (values = TYPE_VALUES (enumtype); values; values = TREE_CHAIN (values))
3216 field_vec->elts[idx++] = TREE_VALUE (values);
3217 return idx;
3220 /* FIELD is a bit-field. We are finishing the processing for its
3221 enclosing type. Issue any appropriate messages and set appropriate
3222 flags. Returns false if an error has been diagnosed. */
3224 static bool
3225 check_bitfield_decl (tree field)
3227 tree type = TREE_TYPE (field);
3228 tree w;
3230 /* Extract the declared width of the bitfield, which has been
3231 temporarily stashed in DECL_INITIAL. */
3232 w = DECL_INITIAL (field);
3233 gcc_assert (w != NULL_TREE);
3234 /* Remove the bit-field width indicator so that the rest of the
3235 compiler does not treat that value as an initializer. */
3236 DECL_INITIAL (field) = NULL_TREE;
3238 /* Detect invalid bit-field type. */
3239 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
3241 error ("bit-field %q+#D with non-integral type", field);
3242 w = error_mark_node;
3244 else
3246 location_t loc = input_location;
3247 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
3248 STRIP_NOPS (w);
3250 /* detect invalid field size. */
3251 input_location = DECL_SOURCE_LOCATION (field);
3252 w = cxx_constant_value (w);
3253 input_location = loc;
3255 if (TREE_CODE (w) != INTEGER_CST)
3257 error ("bit-field %q+D width not an integer constant", field);
3258 w = error_mark_node;
3260 else if (tree_int_cst_sgn (w) < 0)
3262 error ("negative width in bit-field %q+D", field);
3263 w = error_mark_node;
3265 else if (integer_zerop (w) && DECL_NAME (field) != 0)
3267 error ("zero width for bit-field %q+D", field);
3268 w = error_mark_node;
3270 else if ((TREE_CODE (type) != ENUMERAL_TYPE
3271 && TREE_CODE (type) != BOOLEAN_TYPE
3272 && compare_tree_int (w, TYPE_PRECISION (type)) > 0)
3273 || ((TREE_CODE (type) == ENUMERAL_TYPE
3274 || TREE_CODE (type) == BOOLEAN_TYPE)
3275 && tree_int_cst_lt (TYPE_SIZE (type), w)))
3276 warning (0, "width of %q+D exceeds its type", field);
3277 else if (TREE_CODE (type) == ENUMERAL_TYPE
3278 && (0 > (compare_tree_int
3279 (w, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type))))))
3280 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
3283 if (w != error_mark_node)
3285 DECL_SIZE (field) = convert (bitsizetype, w);
3286 DECL_BIT_FIELD (field) = 1;
3287 return true;
3289 else
3291 /* Non-bit-fields are aligned for their type. */
3292 DECL_BIT_FIELD (field) = 0;
3293 CLEAR_DECL_C_BIT_FIELD (field);
3294 return false;
3298 /* FIELD is a non bit-field. We are finishing the processing for its
3299 enclosing type T. Issue any appropriate messages and set appropriate
3300 flags. */
3302 static void
3303 check_field_decl (tree field,
3304 tree t,
3305 int* cant_have_const_ctor,
3306 int* no_const_asn_ref,
3307 int* any_default_members)
3309 tree type = strip_array_types (TREE_TYPE (field));
3311 /* In C++98 an anonymous union cannot contain any fields which would change
3312 the settings of CANT_HAVE_CONST_CTOR and friends. */
3313 if (ANON_UNION_TYPE_P (type) && cxx_dialect < cxx11)
3315 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
3316 structs. So, we recurse through their fields here. */
3317 else if (ANON_AGGR_TYPE_P (type))
3319 tree fields;
3321 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
3322 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
3323 check_field_decl (fields, t, cant_have_const_ctor,
3324 no_const_asn_ref, any_default_members);
3326 /* Check members with class type for constructors, destructors,
3327 etc. */
3328 else if (CLASS_TYPE_P (type))
3330 /* Never let anything with uninheritable virtuals
3331 make it through without complaint. */
3332 abstract_virtuals_error (field, type);
3334 if (TREE_CODE (t) == UNION_TYPE && cxx_dialect < cxx11)
3336 static bool warned;
3337 int oldcount = errorcount;
3338 if (TYPE_NEEDS_CONSTRUCTING (type))
3339 error ("member %q+#D with constructor not allowed in union",
3340 field);
3341 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
3342 error ("member %q+#D with destructor not allowed in union", field);
3343 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
3344 error ("member %q+#D with copy assignment operator not allowed in union",
3345 field);
3346 if (!warned && errorcount > oldcount)
3348 inform (DECL_SOURCE_LOCATION (field), "unrestricted unions "
3349 "only available with -std=c++11 or -std=gnu++11");
3350 warned = true;
3353 else
3355 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
3356 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3357 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
3358 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
3359 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type)
3360 || !TYPE_HAS_COPY_ASSIGN (type));
3361 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type)
3362 || !TYPE_HAS_COPY_CTOR (type));
3363 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type);
3364 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type);
3365 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type)
3366 || TYPE_HAS_COMPLEX_DFLT (type));
3369 if (TYPE_HAS_COPY_CTOR (type)
3370 && !TYPE_HAS_CONST_COPY_CTOR (type))
3371 *cant_have_const_ctor = 1;
3373 if (TYPE_HAS_COPY_ASSIGN (type)
3374 && !TYPE_HAS_CONST_COPY_ASSIGN (type))
3375 *no_const_asn_ref = 1;
3378 check_abi_tags (t, field);
3380 if (DECL_INITIAL (field) != NULL_TREE)
3382 /* `build_class_init_list' does not recognize
3383 non-FIELD_DECLs. */
3384 if (TREE_CODE (t) == UNION_TYPE && *any_default_members != 0)
3385 error ("multiple fields in union %qT initialized", t);
3386 *any_default_members = 1;
3390 /* Check the data members (both static and non-static), class-scoped
3391 typedefs, etc., appearing in the declaration of T. Issue
3392 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
3393 declaration order) of access declarations; each TREE_VALUE in this
3394 list is a USING_DECL.
3396 In addition, set the following flags:
3398 EMPTY_P
3399 The class is empty, i.e., contains no non-static data members.
3401 CANT_HAVE_CONST_CTOR_P
3402 This class cannot have an implicitly generated copy constructor
3403 taking a const reference.
3405 CANT_HAVE_CONST_ASN_REF
3406 This class cannot have an implicitly generated assignment
3407 operator taking a const reference.
3409 All of these flags should be initialized before calling this
3410 function.
3412 Returns a pointer to the end of the TYPE_FIELDs chain; additional
3413 fields can be added by adding to this chain. */
3415 static void
3416 check_field_decls (tree t, tree *access_decls,
3417 int *cant_have_const_ctor_p,
3418 int *no_const_asn_ref_p)
3420 tree *field;
3421 tree *next;
3422 bool has_pointers;
3423 int any_default_members;
3424 int cant_pack = 0;
3425 int field_access = -1;
3427 /* Assume there are no access declarations. */
3428 *access_decls = NULL_TREE;
3429 /* Assume this class has no pointer members. */
3430 has_pointers = false;
3431 /* Assume none of the members of this class have default
3432 initializations. */
3433 any_default_members = 0;
3435 for (field = &TYPE_FIELDS (t); *field; field = next)
3437 tree x = *field;
3438 tree type = TREE_TYPE (x);
3439 int this_field_access;
3441 next = &DECL_CHAIN (x);
3443 if (TREE_CODE (x) == USING_DECL)
3445 /* Save the access declarations for our caller. */
3446 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
3447 continue;
3450 if (TREE_CODE (x) == TYPE_DECL
3451 || TREE_CODE (x) == TEMPLATE_DECL)
3452 continue;
3454 /* If we've gotten this far, it's a data member, possibly static,
3455 or an enumerator. */
3456 if (TREE_CODE (x) != CONST_DECL)
3457 DECL_CONTEXT (x) = t;
3459 /* When this goes into scope, it will be a non-local reference. */
3460 DECL_NONLOCAL (x) = 1;
3462 if (TREE_CODE (t) == UNION_TYPE)
3464 /* [class.union]
3466 If a union contains a static data member, or a member of
3467 reference type, the program is ill-formed. */
3468 if (VAR_P (x))
3470 error ("%q+D may not be static because it is a member of a union", x);
3471 continue;
3473 if (TREE_CODE (type) == REFERENCE_TYPE)
3475 error ("%q+D may not have reference type %qT because"
3476 " it is a member of a union",
3477 x, type);
3478 continue;
3482 /* Perform error checking that did not get done in
3483 grokdeclarator. */
3484 if (TREE_CODE (type) == FUNCTION_TYPE)
3486 error ("field %q+D invalidly declared function type", x);
3487 type = build_pointer_type (type);
3488 TREE_TYPE (x) = type;
3490 else if (TREE_CODE (type) == METHOD_TYPE)
3492 error ("field %q+D invalidly declared method type", x);
3493 type = build_pointer_type (type);
3494 TREE_TYPE (x) = type;
3497 if (type == error_mark_node)
3498 continue;
3500 if (TREE_CODE (x) == CONST_DECL || VAR_P (x))
3501 continue;
3503 /* Now it can only be a FIELD_DECL. */
3505 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3506 CLASSTYPE_NON_AGGREGATE (t) = 1;
3508 /* If at least one non-static data member is non-literal, the whole
3509 class becomes non-literal. Note: if the type is incomplete we
3510 will complain later on. */
3511 if (COMPLETE_TYPE_P (type) && !literal_type_p (type))
3512 CLASSTYPE_LITERAL_P (t) = false;
3514 /* A standard-layout class is a class that:
3516 has the same access control (Clause 11) for all non-static data members,
3517 ... */
3518 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3519 if (field_access == -1)
3520 field_access = this_field_access;
3521 else if (this_field_access != field_access)
3522 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3524 /* If this is of reference type, check if it needs an init. */
3525 if (TREE_CODE (type) == REFERENCE_TYPE)
3527 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3528 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3529 if (DECL_INITIAL (x) == NULL_TREE)
3530 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3532 /* ARM $12.6.2: [A member initializer list] (or, for an
3533 aggregate, initialization by a brace-enclosed list) is the
3534 only way to initialize nonstatic const and reference
3535 members. */
3536 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3537 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3540 type = strip_array_types (type);
3542 if (TYPE_PACKED (t))
3544 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3546 warning
3548 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3550 cant_pack = 1;
3552 else if (DECL_C_BIT_FIELD (x)
3553 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3554 DECL_PACKED (x) = 1;
3557 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3558 /* We don't treat zero-width bitfields as making a class
3559 non-empty. */
3561 else
3563 /* The class is non-empty. */
3564 CLASSTYPE_EMPTY_P (t) = 0;
3565 /* The class is not even nearly empty. */
3566 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3567 /* If one of the data members contains an empty class,
3568 so does T. */
3569 if (CLASS_TYPE_P (type)
3570 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3571 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3574 /* This is used by -Weffc++ (see below). Warn only for pointers
3575 to members which might hold dynamic memory. So do not warn
3576 for pointers to functions or pointers to members. */
3577 if (TYPE_PTR_P (type)
3578 && !TYPE_PTRFN_P (type))
3579 has_pointers = true;
3581 if (CLASS_TYPE_P (type))
3583 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3584 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3585 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3586 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3589 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3590 CLASSTYPE_HAS_MUTABLE (t) = 1;
3592 if (DECL_MUTABLE_P (x))
3594 if (CP_TYPE_CONST_P (type))
3596 error ("member %q+D cannot be declared both %<const%> "
3597 "and %<mutable%>", x);
3598 continue;
3600 if (TREE_CODE (type) == REFERENCE_TYPE)
3602 error ("member %q+D cannot be declared as a %<mutable%> "
3603 "reference", x);
3604 continue;
3608 if (! layout_pod_type_p (type))
3609 /* DR 148 now allows pointers to members (which are POD themselves),
3610 to be allowed in POD structs. */
3611 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3613 if (!std_layout_type_p (type))
3614 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3616 if (! zero_init_p (type))
3617 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3619 /* We set DECL_C_BIT_FIELD in grokbitfield.
3620 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3621 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3622 check_field_decl (x, t,
3623 cant_have_const_ctor_p,
3624 no_const_asn_ref_p,
3625 &any_default_members);
3627 /* Now that we've removed bit-field widths from DECL_INITIAL,
3628 anything left in DECL_INITIAL is an NSDMI that makes the class
3629 non-aggregate. */
3630 if (DECL_INITIAL (x))
3631 CLASSTYPE_NON_AGGREGATE (t) = true;
3633 /* If any field is const, the structure type is pseudo-const. */
3634 if (CP_TYPE_CONST_P (type))
3636 C_TYPE_FIELDS_READONLY (t) = 1;
3637 if (DECL_INITIAL (x) == NULL_TREE)
3638 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3640 /* ARM $12.6.2: [A member initializer list] (or, for an
3641 aggregate, initialization by a brace-enclosed list) is the
3642 only way to initialize nonstatic const and reference
3643 members. */
3644 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3645 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3647 /* A field that is pseudo-const makes the structure likewise. */
3648 else if (CLASS_TYPE_P (type))
3650 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3651 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3652 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3653 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3656 /* Core issue 80: A nonstatic data member is required to have a
3657 different name from the class iff the class has a
3658 user-declared constructor. */
3659 if (constructor_name_p (DECL_NAME (x), t)
3660 && TYPE_HAS_USER_CONSTRUCTOR (t))
3661 permerror (input_location, "field %q+#D with same name as class", x);
3664 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3665 it should also define a copy constructor and an assignment operator to
3666 implement the correct copy semantic (deep vs shallow, etc.). As it is
3667 not feasible to check whether the constructors do allocate dynamic memory
3668 and store it within members, we approximate the warning like this:
3670 -- Warn only if there are members which are pointers
3671 -- Warn only if there is a non-trivial constructor (otherwise,
3672 there cannot be memory allocated).
3673 -- Warn only if there is a non-trivial destructor. We assume that the
3674 user at least implemented the cleanup correctly, and a destructor
3675 is needed to free dynamic memory.
3677 This seems enough for practical purposes. */
3678 if (warn_ecpp
3679 && has_pointers
3680 && TYPE_HAS_USER_CONSTRUCTOR (t)
3681 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3682 && !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
3684 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3686 if (! TYPE_HAS_COPY_CTOR (t))
3688 warning (OPT_Weffc__,
3689 " but does not override %<%T(const %T&)%>", t, t);
3690 if (!TYPE_HAS_COPY_ASSIGN (t))
3691 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3693 else if (! TYPE_HAS_COPY_ASSIGN (t))
3694 warning (OPT_Weffc__,
3695 " but does not override %<operator=(const %T&)%>", t);
3698 /* Non-static data member initializers make the default constructor
3699 non-trivial. */
3700 if (any_default_members)
3702 TYPE_NEEDS_CONSTRUCTING (t) = true;
3703 TYPE_HAS_COMPLEX_DFLT (t) = true;
3706 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3707 if (cant_pack)
3708 TYPE_PACKED (t) = 0;
3710 /* Check anonymous struct/anonymous union fields. */
3711 finish_struct_anon (t);
3713 /* We've built up the list of access declarations in reverse order.
3714 Fix that now. */
3715 *access_decls = nreverse (*access_decls);
3718 /* If TYPE is an empty class type, records its OFFSET in the table of
3719 OFFSETS. */
3721 static int
3722 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3724 splay_tree_node n;
3726 if (!is_empty_class (type))
3727 return 0;
3729 /* Record the location of this empty object in OFFSETS. */
3730 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3731 if (!n)
3732 n = splay_tree_insert (offsets,
3733 (splay_tree_key) offset,
3734 (splay_tree_value) NULL_TREE);
3735 n->value = ((splay_tree_value)
3736 tree_cons (NULL_TREE,
3737 type,
3738 (tree) n->value));
3740 return 0;
3743 /* Returns nonzero if TYPE is an empty class type and there is
3744 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3746 static int
3747 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3749 splay_tree_node n;
3750 tree t;
3752 if (!is_empty_class (type))
3753 return 0;
3755 /* Record the location of this empty object in OFFSETS. */
3756 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3757 if (!n)
3758 return 0;
3760 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3761 if (same_type_p (TREE_VALUE (t), type))
3762 return 1;
3764 return 0;
3767 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3768 F for every subobject, passing it the type, offset, and table of
3769 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3770 be traversed.
3772 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3773 than MAX_OFFSET will not be walked.
3775 If F returns a nonzero value, the traversal ceases, and that value
3776 is returned. Otherwise, returns zero. */
3778 static int
3779 walk_subobject_offsets (tree type,
3780 subobject_offset_fn f,
3781 tree offset,
3782 splay_tree offsets,
3783 tree max_offset,
3784 int vbases_p)
3786 int r = 0;
3787 tree type_binfo = NULL_TREE;
3789 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3790 stop. */
3791 if (max_offset && INT_CST_LT (max_offset, offset))
3792 return 0;
3794 if (type == error_mark_node)
3795 return 0;
3797 if (!TYPE_P (type))
3799 if (abi_version_at_least (2))
3800 type_binfo = type;
3801 type = BINFO_TYPE (type);
3804 if (CLASS_TYPE_P (type))
3806 tree field;
3807 tree binfo;
3808 int i;
3810 /* Avoid recursing into objects that are not interesting. */
3811 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3812 return 0;
3814 /* Record the location of TYPE. */
3815 r = (*f) (type, offset, offsets);
3816 if (r)
3817 return r;
3819 /* Iterate through the direct base classes of TYPE. */
3820 if (!type_binfo)
3821 type_binfo = TYPE_BINFO (type);
3822 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3824 tree binfo_offset;
3826 if (abi_version_at_least (2)
3827 && BINFO_VIRTUAL_P (binfo))
3828 continue;
3830 if (!vbases_p
3831 && BINFO_VIRTUAL_P (binfo)
3832 && !BINFO_PRIMARY_P (binfo))
3833 continue;
3835 if (!abi_version_at_least (2))
3836 binfo_offset = size_binop (PLUS_EXPR,
3837 offset,
3838 BINFO_OFFSET (binfo));
3839 else
3841 tree orig_binfo;
3842 /* We cannot rely on BINFO_OFFSET being set for the base
3843 class yet, but the offsets for direct non-virtual
3844 bases can be calculated by going back to the TYPE. */
3845 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3846 binfo_offset = size_binop (PLUS_EXPR,
3847 offset,
3848 BINFO_OFFSET (orig_binfo));
3851 r = walk_subobject_offsets (binfo,
3853 binfo_offset,
3854 offsets,
3855 max_offset,
3856 (abi_version_at_least (2)
3857 ? /*vbases_p=*/0 : vbases_p));
3858 if (r)
3859 return r;
3862 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3864 unsigned ix;
3865 vec<tree, va_gc> *vbases;
3867 /* Iterate through the virtual base classes of TYPE. In G++
3868 3.2, we included virtual bases in the direct base class
3869 loop above, which results in incorrect results; the
3870 correct offsets for virtual bases are only known when
3871 working with the most derived type. */
3872 if (vbases_p)
3873 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3874 vec_safe_iterate (vbases, ix, &binfo); ix++)
3876 r = walk_subobject_offsets (binfo,
3878 size_binop (PLUS_EXPR,
3879 offset,
3880 BINFO_OFFSET (binfo)),
3881 offsets,
3882 max_offset,
3883 /*vbases_p=*/0);
3884 if (r)
3885 return r;
3887 else
3889 /* We still have to walk the primary base, if it is
3890 virtual. (If it is non-virtual, then it was walked
3891 above.) */
3892 tree vbase = get_primary_binfo (type_binfo);
3894 if (vbase && BINFO_VIRTUAL_P (vbase)
3895 && BINFO_PRIMARY_P (vbase)
3896 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3898 r = (walk_subobject_offsets
3899 (vbase, f, offset,
3900 offsets, max_offset, /*vbases_p=*/0));
3901 if (r)
3902 return r;
3907 /* Iterate through the fields of TYPE. */
3908 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
3909 if (TREE_CODE (field) == FIELD_DECL
3910 && TREE_TYPE (field) != error_mark_node
3911 && !DECL_ARTIFICIAL (field))
3913 tree field_offset;
3915 if (abi_version_at_least (2))
3916 field_offset = byte_position (field);
3917 else
3918 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3919 field_offset = DECL_FIELD_OFFSET (field);
3921 r = walk_subobject_offsets (TREE_TYPE (field),
3923 size_binop (PLUS_EXPR,
3924 offset,
3925 field_offset),
3926 offsets,
3927 max_offset,
3928 /*vbases_p=*/1);
3929 if (r)
3930 return r;
3933 else if (TREE_CODE (type) == ARRAY_TYPE)
3935 tree element_type = strip_array_types (type);
3936 tree domain = TYPE_DOMAIN (type);
3937 tree index;
3939 /* Avoid recursing into objects that are not interesting. */
3940 if (!CLASS_TYPE_P (element_type)
3941 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3942 return 0;
3944 /* Step through each of the elements in the array. */
3945 for (index = size_zero_node;
3946 /* G++ 3.2 had an off-by-one error here. */
3947 (abi_version_at_least (2)
3948 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3949 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3950 index = size_binop (PLUS_EXPR, index, size_one_node))
3952 r = walk_subobject_offsets (TREE_TYPE (type),
3954 offset,
3955 offsets,
3956 max_offset,
3957 /*vbases_p=*/1);
3958 if (r)
3959 return r;
3960 offset = size_binop (PLUS_EXPR, offset,
3961 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3962 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3963 there's no point in iterating through the remaining
3964 elements of the array. */
3965 if (max_offset && INT_CST_LT (max_offset, offset))
3966 break;
3970 return 0;
3973 /* Record all of the empty subobjects of TYPE (either a type or a
3974 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3975 is being placed at OFFSET; otherwise, it is a base class that is
3976 being placed at OFFSET. */
3978 static void
3979 record_subobject_offsets (tree type,
3980 tree offset,
3981 splay_tree offsets,
3982 bool is_data_member)
3984 tree max_offset;
3985 /* If recording subobjects for a non-static data member or a
3986 non-empty base class , we do not need to record offsets beyond
3987 the size of the biggest empty class. Additional data members
3988 will go at the end of the class. Additional base classes will go
3989 either at offset zero (if empty, in which case they cannot
3990 overlap with offsets past the size of the biggest empty class) or
3991 at the end of the class.
3993 However, if we are placing an empty base class, then we must record
3994 all offsets, as either the empty class is at offset zero (where
3995 other empty classes might later be placed) or at the end of the
3996 class (where other objects might then be placed, so other empty
3997 subobjects might later overlap). */
3998 if (is_data_member
3999 || !is_empty_class (BINFO_TYPE (type)))
4000 max_offset = sizeof_biggest_empty_class;
4001 else
4002 max_offset = NULL_TREE;
4003 walk_subobject_offsets (type, record_subobject_offset, offset,
4004 offsets, max_offset, is_data_member);
4007 /* Returns nonzero if any of the empty subobjects of TYPE (located at
4008 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
4009 virtual bases of TYPE are examined. */
4011 static int
4012 layout_conflict_p (tree type,
4013 tree offset,
4014 splay_tree offsets,
4015 int vbases_p)
4017 splay_tree_node max_node;
4019 /* Get the node in OFFSETS that indicates the maximum offset where
4020 an empty subobject is located. */
4021 max_node = splay_tree_max (offsets);
4022 /* If there aren't any empty subobjects, then there's no point in
4023 performing this check. */
4024 if (!max_node)
4025 return 0;
4027 return walk_subobject_offsets (type, check_subobject_offset, offset,
4028 offsets, (tree) (max_node->key),
4029 vbases_p);
4032 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
4033 non-static data member of the type indicated by RLI. BINFO is the
4034 binfo corresponding to the base subobject, OFFSETS maps offsets to
4035 types already located at those offsets. This function determines
4036 the position of the DECL. */
4038 static void
4039 layout_nonempty_base_or_field (record_layout_info rli,
4040 tree decl,
4041 tree binfo,
4042 splay_tree offsets)
4044 tree offset = NULL_TREE;
4045 bool field_p;
4046 tree type;
4048 if (binfo)
4050 /* For the purposes of determining layout conflicts, we want to
4051 use the class type of BINFO; TREE_TYPE (DECL) will be the
4052 CLASSTYPE_AS_BASE version, which does not contain entries for
4053 zero-sized bases. */
4054 type = TREE_TYPE (binfo);
4055 field_p = false;
4057 else
4059 type = TREE_TYPE (decl);
4060 field_p = true;
4063 /* Try to place the field. It may take more than one try if we have
4064 a hard time placing the field without putting two objects of the
4065 same type at the same address. */
4066 while (1)
4068 struct record_layout_info_s old_rli = *rli;
4070 /* Place this field. */
4071 place_field (rli, decl);
4072 offset = byte_position (decl);
4074 /* We have to check to see whether or not there is already
4075 something of the same type at the offset we're about to use.
4076 For example, consider:
4078 struct S {};
4079 struct T : public S { int i; };
4080 struct U : public S, public T {};
4082 Here, we put S at offset zero in U. Then, we can't put T at
4083 offset zero -- its S component would be at the same address
4084 as the S we already allocated. So, we have to skip ahead.
4085 Since all data members, including those whose type is an
4086 empty class, have nonzero size, any overlap can happen only
4087 with a direct or indirect base-class -- it can't happen with
4088 a data member. */
4089 /* In a union, overlap is permitted; all members are placed at
4090 offset zero. */
4091 if (TREE_CODE (rli->t) == UNION_TYPE)
4092 break;
4093 /* G++ 3.2 did not check for overlaps when placing a non-empty
4094 virtual base. */
4095 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
4096 break;
4097 if (layout_conflict_p (field_p ? type : binfo, offset,
4098 offsets, field_p))
4100 /* Strip off the size allocated to this field. That puts us
4101 at the first place we could have put the field with
4102 proper alignment. */
4103 *rli = old_rli;
4105 /* Bump up by the alignment required for the type. */
4106 rli->bitpos
4107 = size_binop (PLUS_EXPR, rli->bitpos,
4108 bitsize_int (binfo
4109 ? CLASSTYPE_ALIGN (type)
4110 : TYPE_ALIGN (type)));
4111 normalize_rli (rli);
4113 else
4114 /* There was no conflict. We're done laying out this field. */
4115 break;
4118 /* Now that we know where it will be placed, update its
4119 BINFO_OFFSET. */
4120 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
4121 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
4122 this point because their BINFO_OFFSET is copied from another
4123 hierarchy. Therefore, we may not need to add the entire
4124 OFFSET. */
4125 propagate_binfo_offsets (binfo,
4126 size_diffop_loc (input_location,
4127 convert (ssizetype, offset),
4128 convert (ssizetype,
4129 BINFO_OFFSET (binfo))));
4132 /* Returns true if TYPE is empty and OFFSET is nonzero. */
4134 static int
4135 empty_base_at_nonzero_offset_p (tree type,
4136 tree offset,
4137 splay_tree /*offsets*/)
4139 return is_empty_class (type) && !integer_zerop (offset);
4142 /* Layout the empty base BINFO. EOC indicates the byte currently just
4143 past the end of the class, and should be correctly aligned for a
4144 class of the type indicated by BINFO; OFFSETS gives the offsets of
4145 the empty bases allocated so far. T is the most derived
4146 type. Return nonzero iff we added it at the end. */
4148 static bool
4149 layout_empty_base (record_layout_info rli, tree binfo,
4150 tree eoc, splay_tree offsets)
4152 tree alignment;
4153 tree basetype = BINFO_TYPE (binfo);
4154 bool atend = false;
4156 /* This routine should only be used for empty classes. */
4157 gcc_assert (is_empty_class (basetype));
4158 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
4160 if (!integer_zerop (BINFO_OFFSET (binfo)))
4162 if (abi_version_at_least (2))
4163 propagate_binfo_offsets
4164 (binfo, size_diffop_loc (input_location,
4165 size_zero_node, BINFO_OFFSET (binfo)));
4166 else
4167 warning (OPT_Wabi,
4168 "offset of empty base %qT may not be ABI-compliant and may"
4169 "change in a future version of GCC",
4170 BINFO_TYPE (binfo));
4173 /* This is an empty base class. We first try to put it at offset
4174 zero. */
4175 if (layout_conflict_p (binfo,
4176 BINFO_OFFSET (binfo),
4177 offsets,
4178 /*vbases_p=*/0))
4180 /* That didn't work. Now, we move forward from the next
4181 available spot in the class. */
4182 atend = true;
4183 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
4184 while (1)
4186 if (!layout_conflict_p (binfo,
4187 BINFO_OFFSET (binfo),
4188 offsets,
4189 /*vbases_p=*/0))
4190 /* We finally found a spot where there's no overlap. */
4191 break;
4193 /* There's overlap here, too. Bump along to the next spot. */
4194 propagate_binfo_offsets (binfo, alignment);
4198 if (CLASSTYPE_USER_ALIGN (basetype))
4200 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
4201 if (warn_packed)
4202 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
4203 TYPE_USER_ALIGN (rli->t) = 1;
4206 return atend;
4209 /* Layout the base given by BINFO in the class indicated by RLI.
4210 *BASE_ALIGN is a running maximum of the alignments of
4211 any base class. OFFSETS gives the location of empty base
4212 subobjects. T is the most derived type. Return nonzero if the new
4213 object cannot be nearly-empty. A new FIELD_DECL is inserted at
4214 *NEXT_FIELD, unless BINFO is for an empty base class.
4216 Returns the location at which the next field should be inserted. */
4218 static tree *
4219 build_base_field (record_layout_info rli, tree binfo,
4220 splay_tree offsets, tree *next_field)
4222 tree t = rli->t;
4223 tree basetype = BINFO_TYPE (binfo);
4225 if (!COMPLETE_TYPE_P (basetype))
4226 /* This error is now reported in xref_tag, thus giving better
4227 location information. */
4228 return next_field;
4230 /* Place the base class. */
4231 if (!is_empty_class (basetype))
4233 tree decl;
4235 /* The containing class is non-empty because it has a non-empty
4236 base class. */
4237 CLASSTYPE_EMPTY_P (t) = 0;
4239 /* Create the FIELD_DECL. */
4240 decl = build_decl (input_location,
4241 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
4242 DECL_ARTIFICIAL (decl) = 1;
4243 DECL_IGNORED_P (decl) = 1;
4244 DECL_FIELD_CONTEXT (decl) = t;
4245 if (CLASSTYPE_AS_BASE (basetype))
4247 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
4248 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
4249 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
4250 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
4251 DECL_MODE (decl) = TYPE_MODE (basetype);
4252 DECL_FIELD_IS_BASE (decl) = 1;
4254 /* Try to place the field. It may take more than one try if we
4255 have a hard time placing the field without putting two
4256 objects of the same type at the same address. */
4257 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
4258 /* Add the new FIELD_DECL to the list of fields for T. */
4259 DECL_CHAIN (decl) = *next_field;
4260 *next_field = decl;
4261 next_field = &DECL_CHAIN (decl);
4264 else
4266 tree eoc;
4267 bool atend;
4269 /* On some platforms (ARM), even empty classes will not be
4270 byte-aligned. */
4271 eoc = round_up_loc (input_location,
4272 rli_size_unit_so_far (rli),
4273 CLASSTYPE_ALIGN_UNIT (basetype));
4274 atend = layout_empty_base (rli, binfo, eoc, offsets);
4275 /* A nearly-empty class "has no proper base class that is empty,
4276 not morally virtual, and at an offset other than zero." */
4277 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
4279 if (atend)
4280 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4281 /* The check above (used in G++ 3.2) is insufficient because
4282 an empty class placed at offset zero might itself have an
4283 empty base at a nonzero offset. */
4284 else if (walk_subobject_offsets (basetype,
4285 empty_base_at_nonzero_offset_p,
4286 size_zero_node,
4287 /*offsets=*/NULL,
4288 /*max_offset=*/NULL_TREE,
4289 /*vbases_p=*/true))
4291 if (abi_version_at_least (2))
4292 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4293 else
4294 warning (OPT_Wabi,
4295 "class %qT will be considered nearly empty in a "
4296 "future version of GCC", t);
4300 /* We do not create a FIELD_DECL for empty base classes because
4301 it might overlap some other field. We want to be able to
4302 create CONSTRUCTORs for the class by iterating over the
4303 FIELD_DECLs, and the back end does not handle overlapping
4304 FIELD_DECLs. */
4306 /* An empty virtual base causes a class to be non-empty
4307 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
4308 here because that was already done when the virtual table
4309 pointer was created. */
4312 /* Record the offsets of BINFO and its base subobjects. */
4313 record_subobject_offsets (binfo,
4314 BINFO_OFFSET (binfo),
4315 offsets,
4316 /*is_data_member=*/false);
4318 return next_field;
4321 /* Layout all of the non-virtual base classes. Record empty
4322 subobjects in OFFSETS. T is the most derived type. Return nonzero
4323 if the type cannot be nearly empty. The fields created
4324 corresponding to the base classes will be inserted at
4325 *NEXT_FIELD. */
4327 static void
4328 build_base_fields (record_layout_info rli,
4329 splay_tree offsets, tree *next_field)
4331 /* Chain to hold all the new FIELD_DECLs which stand in for base class
4332 subobjects. */
4333 tree t = rli->t;
4334 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
4335 int i;
4337 /* The primary base class is always allocated first. */
4338 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
4339 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
4340 offsets, next_field);
4342 /* Now allocate the rest of the bases. */
4343 for (i = 0; i < n_baseclasses; ++i)
4345 tree base_binfo;
4347 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
4349 /* The primary base was already allocated above, so we don't
4350 need to allocate it again here. */
4351 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
4352 continue;
4354 /* Virtual bases are added at the end (a primary virtual base
4355 will have already been added). */
4356 if (BINFO_VIRTUAL_P (base_binfo))
4357 continue;
4359 next_field = build_base_field (rli, base_binfo,
4360 offsets, next_field);
4364 /* Go through the TYPE_METHODS of T issuing any appropriate
4365 diagnostics, figuring out which methods override which other
4366 methods, and so forth. */
4368 static void
4369 check_methods (tree t)
4371 tree x;
4373 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
4375 check_for_override (x, t);
4376 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
4377 error ("initializer specified for non-virtual method %q+D", x);
4378 /* The name of the field is the original field name
4379 Save this in auxiliary field for later overloading. */
4380 if (DECL_VINDEX (x))
4382 TYPE_POLYMORPHIC_P (t) = 1;
4383 if (DECL_PURE_VIRTUAL_P (x))
4384 vec_safe_push (CLASSTYPE_PURE_VIRTUALS (t), x);
4386 /* All user-provided destructors are non-trivial.
4387 Constructors and assignment ops are handled in
4388 grok_special_member_properties. */
4389 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
4390 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
4394 /* FN is a constructor or destructor. Clone the declaration to create
4395 a specialized in-charge or not-in-charge version, as indicated by
4396 NAME. */
4398 static tree
4399 build_clone (tree fn, tree name)
4401 tree parms;
4402 tree clone;
4404 /* Copy the function. */
4405 clone = copy_decl (fn);
4406 /* Reset the function name. */
4407 DECL_NAME (clone) = name;
4408 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
4409 /* Remember where this function came from. */
4410 DECL_ABSTRACT_ORIGIN (clone) = fn;
4411 /* Make it easy to find the CLONE given the FN. */
4412 DECL_CHAIN (clone) = DECL_CHAIN (fn);
4413 DECL_CHAIN (fn) = clone;
4415 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
4416 if (TREE_CODE (clone) == TEMPLATE_DECL)
4418 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
4419 DECL_TEMPLATE_RESULT (clone) = result;
4420 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
4421 DECL_TI_TEMPLATE (result) = clone;
4422 TREE_TYPE (clone) = TREE_TYPE (result);
4423 return clone;
4426 DECL_CLONED_FUNCTION (clone) = fn;
4427 /* There's no pending inline data for this function. */
4428 DECL_PENDING_INLINE_INFO (clone) = NULL;
4429 DECL_PENDING_INLINE_P (clone) = 0;
4431 /* The base-class destructor is not virtual. */
4432 if (name == base_dtor_identifier)
4434 DECL_VIRTUAL_P (clone) = 0;
4435 if (TREE_CODE (clone) != TEMPLATE_DECL)
4436 DECL_VINDEX (clone) = NULL_TREE;
4439 /* If there was an in-charge parameter, drop it from the function
4440 type. */
4441 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4443 tree basetype;
4444 tree parmtypes;
4445 tree exceptions;
4447 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4448 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4449 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
4450 /* Skip the `this' parameter. */
4451 parmtypes = TREE_CHAIN (parmtypes);
4452 /* Skip the in-charge parameter. */
4453 parmtypes = TREE_CHAIN (parmtypes);
4454 /* And the VTT parm, in a complete [cd]tor. */
4455 if (DECL_HAS_VTT_PARM_P (fn)
4456 && ! DECL_NEEDS_VTT_PARM_P (clone))
4457 parmtypes = TREE_CHAIN (parmtypes);
4458 /* If this is subobject constructor or destructor, add the vtt
4459 parameter. */
4460 TREE_TYPE (clone)
4461 = build_method_type_directly (basetype,
4462 TREE_TYPE (TREE_TYPE (clone)),
4463 parmtypes);
4464 if (exceptions)
4465 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
4466 exceptions);
4467 TREE_TYPE (clone)
4468 = cp_build_type_attribute_variant (TREE_TYPE (clone),
4469 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
4472 /* Copy the function parameters. */
4473 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
4474 /* Remove the in-charge parameter. */
4475 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4477 DECL_CHAIN (DECL_ARGUMENTS (clone))
4478 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4479 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
4481 /* And the VTT parm, in a complete [cd]tor. */
4482 if (DECL_HAS_VTT_PARM_P (fn))
4484 if (DECL_NEEDS_VTT_PARM_P (clone))
4485 DECL_HAS_VTT_PARM_P (clone) = 1;
4486 else
4488 DECL_CHAIN (DECL_ARGUMENTS (clone))
4489 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4490 DECL_HAS_VTT_PARM_P (clone) = 0;
4494 for (parms = DECL_ARGUMENTS (clone); parms; parms = DECL_CHAIN (parms))
4496 DECL_CONTEXT (parms) = clone;
4497 cxx_dup_lang_specific_decl (parms);
4500 /* Create the RTL for this function. */
4501 SET_DECL_RTL (clone, NULL);
4502 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
4504 if (pch_file)
4505 note_decl_for_pch (clone);
4507 return clone;
4510 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4511 not invoke this function directly.
4513 For a non-thunk function, returns the address of the slot for storing
4514 the function it is a clone of. Otherwise returns NULL_TREE.
4516 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4517 cloned_function is unset. This is to support the separate
4518 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4519 on a template makes sense, but not the former. */
4521 tree *
4522 decl_cloned_function_p (const_tree decl, bool just_testing)
4524 tree *ptr;
4525 if (just_testing)
4526 decl = STRIP_TEMPLATE (decl);
4528 if (TREE_CODE (decl) != FUNCTION_DECL
4529 || !DECL_LANG_SPECIFIC (decl)
4530 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
4532 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4533 if (!just_testing)
4534 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
4535 else
4536 #endif
4537 return NULL;
4540 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
4541 if (just_testing && *ptr == NULL_TREE)
4542 return NULL;
4543 else
4544 return ptr;
4547 /* Produce declarations for all appropriate clones of FN. If
4548 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4549 CLASTYPE_METHOD_VEC as well. */
4551 void
4552 clone_function_decl (tree fn, int update_method_vec_p)
4554 tree clone;
4556 /* Avoid inappropriate cloning. */
4557 if (DECL_CHAIN (fn)
4558 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (fn)))
4559 return;
4561 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4563 /* For each constructor, we need two variants: an in-charge version
4564 and a not-in-charge version. */
4565 clone = build_clone (fn, complete_ctor_identifier);
4566 if (update_method_vec_p)
4567 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4568 clone = build_clone (fn, base_ctor_identifier);
4569 if (update_method_vec_p)
4570 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4572 else
4574 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4576 /* For each destructor, we need three variants: an in-charge
4577 version, a not-in-charge version, and an in-charge deleting
4578 version. We clone the deleting version first because that
4579 means it will go second on the TYPE_METHODS list -- and that
4580 corresponds to the correct layout order in the virtual
4581 function table.
4583 For a non-virtual destructor, we do not build a deleting
4584 destructor. */
4585 if (DECL_VIRTUAL_P (fn))
4587 clone = build_clone (fn, deleting_dtor_identifier);
4588 if (update_method_vec_p)
4589 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4591 clone = build_clone (fn, complete_dtor_identifier);
4592 if (update_method_vec_p)
4593 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4594 clone = build_clone (fn, base_dtor_identifier);
4595 if (update_method_vec_p)
4596 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4599 /* Note that this is an abstract function that is never emitted. */
4600 DECL_ABSTRACT (fn) = 1;
4603 /* DECL is an in charge constructor, which is being defined. This will
4604 have had an in class declaration, from whence clones were
4605 declared. An out-of-class definition can specify additional default
4606 arguments. As it is the clones that are involved in overload
4607 resolution, we must propagate the information from the DECL to its
4608 clones. */
4610 void
4611 adjust_clone_args (tree decl)
4613 tree clone;
4615 for (clone = DECL_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4616 clone = DECL_CHAIN (clone))
4618 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4619 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4620 tree decl_parms, clone_parms;
4622 clone_parms = orig_clone_parms;
4624 /* Skip the 'this' parameter. */
4625 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4626 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4628 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4629 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4630 if (DECL_HAS_VTT_PARM_P (decl))
4631 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4633 clone_parms = orig_clone_parms;
4634 if (DECL_HAS_VTT_PARM_P (clone))
4635 clone_parms = TREE_CHAIN (clone_parms);
4637 for (decl_parms = orig_decl_parms; decl_parms;
4638 decl_parms = TREE_CHAIN (decl_parms),
4639 clone_parms = TREE_CHAIN (clone_parms))
4641 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4642 TREE_TYPE (clone_parms)));
4644 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4646 /* A default parameter has been added. Adjust the
4647 clone's parameters. */
4648 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4649 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4650 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4651 tree type;
4653 clone_parms = orig_decl_parms;
4655 if (DECL_HAS_VTT_PARM_P (clone))
4657 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4658 TREE_VALUE (orig_clone_parms),
4659 clone_parms);
4660 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4662 type = build_method_type_directly (basetype,
4663 TREE_TYPE (TREE_TYPE (clone)),
4664 clone_parms);
4665 if (exceptions)
4666 type = build_exception_variant (type, exceptions);
4667 if (attrs)
4668 type = cp_build_type_attribute_variant (type, attrs);
4669 TREE_TYPE (clone) = type;
4671 clone_parms = NULL_TREE;
4672 break;
4675 gcc_assert (!clone_parms);
4679 /* For each of the constructors and destructors in T, create an
4680 in-charge and not-in-charge variant. */
4682 static void
4683 clone_constructors_and_destructors (tree t)
4685 tree fns;
4687 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4688 out now. */
4689 if (!CLASSTYPE_METHOD_VEC (t))
4690 return;
4692 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4693 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4694 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4695 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4698 /* Deduce noexcept for a destructor DTOR. */
4700 void
4701 deduce_noexcept_on_destructor (tree dtor)
4703 if (!TYPE_RAISES_EXCEPTIONS (TREE_TYPE (dtor)))
4705 tree ctx = DECL_CONTEXT (dtor);
4706 tree implicit_fn = implicitly_declare_fn (sfk_destructor, ctx,
4707 /*const_p=*/false,
4708 NULL, NULL);
4709 tree eh_spec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (implicit_fn));
4710 TREE_TYPE (dtor) = build_exception_variant (TREE_TYPE (dtor), eh_spec);
4714 /* For each destructor in T, deduce noexcept:
4716 12.4/3: A declaration of a destructor that does not have an
4717 exception-specification is implicitly considered to have the
4718 same exception-specification as an implicit declaration (15.4). */
4720 static void
4721 deduce_noexcept_on_destructors (tree t)
4723 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4724 out now. */
4725 if (!CLASSTYPE_METHOD_VEC (t))
4726 return;
4728 for (tree fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4729 deduce_noexcept_on_destructor (OVL_CURRENT (fns));
4732 /* Subroutine of set_one_vmethod_tm_attributes. Search base classes
4733 of TYPE for virtual functions which FNDECL overrides. Return a
4734 mask of the tm attributes found therein. */
4736 static int
4737 look_for_tm_attr_overrides (tree type, tree fndecl)
4739 tree binfo = TYPE_BINFO (type);
4740 tree base_binfo;
4741 int ix, found = 0;
4743 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ++ix)
4745 tree o, basetype = BINFO_TYPE (base_binfo);
4747 if (!TYPE_POLYMORPHIC_P (basetype))
4748 continue;
4750 o = look_for_overrides_here (basetype, fndecl);
4751 if (o)
4752 found |= tm_attr_to_mask (find_tm_attribute
4753 (TYPE_ATTRIBUTES (TREE_TYPE (o))));
4754 else
4755 found |= look_for_tm_attr_overrides (basetype, fndecl);
4758 return found;
4761 /* Subroutine of set_method_tm_attributes. Handle the checks and
4762 inheritance for one virtual method FNDECL. */
4764 static void
4765 set_one_vmethod_tm_attributes (tree type, tree fndecl)
4767 tree tm_attr;
4768 int found, have;
4770 found = look_for_tm_attr_overrides (type, fndecl);
4772 /* If FNDECL doesn't actually override anything (i.e. T is the
4773 class that first declares FNDECL virtual), then we're done. */
4774 if (found == 0)
4775 return;
4777 tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (TREE_TYPE (fndecl)));
4778 have = tm_attr_to_mask (tm_attr);
4780 /* Intel STM Language Extension 3.0, Section 4.2 table 4:
4781 tm_pure must match exactly, otherwise no weakening of
4782 tm_safe > tm_callable > nothing. */
4783 /* ??? The tm_pure attribute didn't make the transition to the
4784 multivendor language spec. */
4785 if (have == TM_ATTR_PURE)
4787 if (found != TM_ATTR_PURE)
4789 found &= -found;
4790 goto err_override;
4793 /* If the overridden function is tm_pure, then FNDECL must be. */
4794 else if (found == TM_ATTR_PURE && tm_attr)
4795 goto err_override;
4796 /* Look for base class combinations that cannot be satisfied. */
4797 else if (found != TM_ATTR_PURE && (found & TM_ATTR_PURE))
4799 found &= ~TM_ATTR_PURE;
4800 found &= -found;
4801 error_at (DECL_SOURCE_LOCATION (fndecl),
4802 "method overrides both %<transaction_pure%> and %qE methods",
4803 tm_mask_to_attr (found));
4805 /* If FNDECL did not declare an attribute, then inherit the most
4806 restrictive one. */
4807 else if (tm_attr == NULL)
4809 apply_tm_attr (fndecl, tm_mask_to_attr (found & -found));
4811 /* Otherwise validate that we're not weaker than a function
4812 that is being overridden. */
4813 else
4815 found &= -found;
4816 if (found <= TM_ATTR_CALLABLE && have > found)
4817 goto err_override;
4819 return;
4821 err_override:
4822 error_at (DECL_SOURCE_LOCATION (fndecl),
4823 "method declared %qE overriding %qE method",
4824 tm_attr, tm_mask_to_attr (found));
4827 /* For each of the methods in T, propagate a class-level tm attribute. */
4829 static void
4830 set_method_tm_attributes (tree t)
4832 tree class_tm_attr, fndecl;
4834 /* Don't bother collecting tm attributes if transactional memory
4835 support is not enabled. */
4836 if (!flag_tm)
4837 return;
4839 /* Process virtual methods first, as they inherit directly from the
4840 base virtual function and also require validation of new attributes. */
4841 if (TYPE_CONTAINS_VPTR_P (t))
4843 tree vchain;
4844 for (vchain = BINFO_VIRTUALS (TYPE_BINFO (t)); vchain;
4845 vchain = TREE_CHAIN (vchain))
4847 fndecl = BV_FN (vchain);
4848 if (DECL_THUNK_P (fndecl))
4849 fndecl = THUNK_TARGET (fndecl);
4850 set_one_vmethod_tm_attributes (t, fndecl);
4854 /* If the class doesn't have an attribute, nothing more to do. */
4855 class_tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (t));
4856 if (class_tm_attr == NULL)
4857 return;
4859 /* Any method that does not yet have a tm attribute inherits
4860 the one from the class. */
4861 for (fndecl = TYPE_METHODS (t); fndecl; fndecl = TREE_CHAIN (fndecl))
4863 if (!find_tm_attribute (TYPE_ATTRIBUTES (TREE_TYPE (fndecl))))
4864 apply_tm_attr (fndecl, class_tm_attr);
4868 /* Returns true iff class T has a user-defined constructor other than
4869 the default constructor. */
4871 bool
4872 type_has_user_nondefault_constructor (tree t)
4874 tree fns;
4876 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4877 return false;
4879 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4881 tree fn = OVL_CURRENT (fns);
4882 if (!DECL_ARTIFICIAL (fn)
4883 && (TREE_CODE (fn) == TEMPLATE_DECL
4884 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4885 != NULL_TREE)))
4886 return true;
4889 return false;
4892 /* Returns the defaulted constructor if T has one. Otherwise, returns
4893 NULL_TREE. */
4895 tree
4896 in_class_defaulted_default_constructor (tree t)
4898 tree fns, args;
4900 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4901 return NULL_TREE;
4903 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4905 tree fn = OVL_CURRENT (fns);
4907 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4909 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4910 while (args && TREE_PURPOSE (args))
4911 args = TREE_CHAIN (args);
4912 if (!args || args == void_list_node)
4913 return fn;
4917 return NULL_TREE;
4920 /* Returns true iff FN is a user-provided function, i.e. user-declared
4921 and not defaulted at its first declaration; or explicit, private,
4922 protected, or non-const. */
4924 bool
4925 user_provided_p (tree fn)
4927 if (TREE_CODE (fn) == TEMPLATE_DECL)
4928 return true;
4929 else
4930 return (!DECL_ARTIFICIAL (fn)
4931 && !(DECL_INITIALIZED_IN_CLASS_P (fn)
4932 && (DECL_DEFAULTED_FN (fn) || DECL_DELETED_FN (fn))));
4935 /* Returns true iff class T has a user-provided constructor. */
4937 bool
4938 type_has_user_provided_constructor (tree t)
4940 tree fns;
4942 if (!CLASS_TYPE_P (t))
4943 return false;
4945 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4946 return false;
4948 /* This can happen in error cases; avoid crashing. */
4949 if (!CLASSTYPE_METHOD_VEC (t))
4950 return false;
4952 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4953 if (user_provided_p (OVL_CURRENT (fns)))
4954 return true;
4956 return false;
4959 /* Returns true iff class T has a user-provided default constructor. */
4961 bool
4962 type_has_user_provided_default_constructor (tree t)
4964 tree fns;
4966 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4967 return false;
4969 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4971 tree fn = OVL_CURRENT (fns);
4972 if (TREE_CODE (fn) == FUNCTION_DECL
4973 && user_provided_p (fn)
4974 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)))
4975 return true;
4978 return false;
4981 /* TYPE is being used as a virtual base, and has a non-trivial move
4982 assignment. Return true if this is due to there being a user-provided
4983 move assignment in TYPE or one of its subobjects; if there isn't, then
4984 multiple move assignment can't cause any harm. */
4986 bool
4987 vbase_has_user_provided_move_assign (tree type)
4989 /* Does the type itself have a user-provided move assignment operator? */
4990 for (tree fns
4991 = lookup_fnfields_slot_nolazy (type, ansi_assopname (NOP_EXPR));
4992 fns; fns = OVL_NEXT (fns))
4994 tree fn = OVL_CURRENT (fns);
4995 if (move_fn_p (fn) && user_provided_p (fn))
4996 return true;
4999 /* Do any of its bases? */
5000 tree binfo = TYPE_BINFO (type);
5001 tree base_binfo;
5002 for (int i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5003 if (vbase_has_user_provided_move_assign (BINFO_TYPE (base_binfo)))
5004 return true;
5006 /* Or non-static data members? */
5007 for (tree field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
5009 if (TREE_CODE (field) == FIELD_DECL
5010 && CLASS_TYPE_P (TREE_TYPE (field))
5011 && vbase_has_user_provided_move_assign (TREE_TYPE (field)))
5012 return true;
5015 /* Seems not. */
5016 return false;
5019 /* If default-initialization leaves part of TYPE uninitialized, returns
5020 a DECL for the field or TYPE itself (DR 253). */
5022 tree
5023 default_init_uninitialized_part (tree type)
5025 tree t, r, binfo;
5026 int i;
5028 type = strip_array_types (type);
5029 if (!CLASS_TYPE_P (type))
5030 return type;
5031 if (type_has_user_provided_default_constructor (type))
5032 return NULL_TREE;
5033 for (binfo = TYPE_BINFO (type), i = 0;
5034 BINFO_BASE_ITERATE (binfo, i, t); ++i)
5036 r = default_init_uninitialized_part (BINFO_TYPE (t));
5037 if (r)
5038 return r;
5040 for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t))
5041 if (TREE_CODE (t) == FIELD_DECL
5042 && !DECL_ARTIFICIAL (t)
5043 && !DECL_INITIAL (t))
5045 r = default_init_uninitialized_part (TREE_TYPE (t));
5046 if (r)
5047 return DECL_P (r) ? r : t;
5050 return NULL_TREE;
5053 /* Returns true iff for class T, a trivial synthesized default constructor
5054 would be constexpr. */
5056 bool
5057 trivial_default_constructor_is_constexpr (tree t)
5059 /* A defaulted trivial default constructor is constexpr
5060 if there is nothing to initialize. */
5061 gcc_assert (!TYPE_HAS_COMPLEX_DFLT (t));
5062 return is_really_empty_class (t);
5065 /* Returns true iff class T has a constexpr default constructor. */
5067 bool
5068 type_has_constexpr_default_constructor (tree t)
5070 tree fns;
5072 if (!CLASS_TYPE_P (t))
5074 /* The caller should have stripped an enclosing array. */
5075 gcc_assert (TREE_CODE (t) != ARRAY_TYPE);
5076 return false;
5078 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t))
5080 if (!TYPE_HAS_COMPLEX_DFLT (t))
5081 return trivial_default_constructor_is_constexpr (t);
5082 /* Non-trivial, we need to check subobject constructors. */
5083 lazily_declare_fn (sfk_constructor, t);
5085 fns = locate_ctor (t);
5086 return (fns && DECL_DECLARED_CONSTEXPR_P (fns));
5089 /* Returns true iff class TYPE has a virtual destructor. */
5091 bool
5092 type_has_virtual_destructor (tree type)
5094 tree dtor;
5096 if (!CLASS_TYPE_P (type))
5097 return false;
5099 gcc_assert (COMPLETE_TYPE_P (type));
5100 dtor = CLASSTYPE_DESTRUCTORS (type);
5101 return (dtor && DECL_VIRTUAL_P (dtor));
5104 /* Returns true iff class T has a move constructor. */
5106 bool
5107 type_has_move_constructor (tree t)
5109 tree fns;
5111 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
5113 gcc_assert (COMPLETE_TYPE_P (t));
5114 lazily_declare_fn (sfk_move_constructor, t);
5117 if (!CLASSTYPE_METHOD_VEC (t))
5118 return false;
5120 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
5121 if (move_fn_p (OVL_CURRENT (fns)))
5122 return true;
5124 return false;
5127 /* Returns true iff class T has a move assignment operator. */
5129 bool
5130 type_has_move_assign (tree t)
5132 tree fns;
5134 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
5136 gcc_assert (COMPLETE_TYPE_P (t));
5137 lazily_declare_fn (sfk_move_assignment, t);
5140 for (fns = lookup_fnfields_slot_nolazy (t, ansi_assopname (NOP_EXPR));
5141 fns; fns = OVL_NEXT (fns))
5142 if (move_fn_p (OVL_CURRENT (fns)))
5143 return true;
5145 return false;
5148 /* Returns true iff class T has a move constructor that was explicitly
5149 declared in the class body. Note that this is different from
5150 "user-provided", which doesn't include functions that are defaulted in
5151 the class. */
5153 bool
5154 type_has_user_declared_move_constructor (tree t)
5156 tree fns;
5158 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
5159 return false;
5161 if (!CLASSTYPE_METHOD_VEC (t))
5162 return false;
5164 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
5166 tree fn = OVL_CURRENT (fns);
5167 if (move_fn_p (fn) && !DECL_ARTIFICIAL (fn))
5168 return true;
5171 return false;
5174 /* Returns true iff class T has a move assignment operator that was
5175 explicitly declared in the class body. */
5177 bool
5178 type_has_user_declared_move_assign (tree t)
5180 tree fns;
5182 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
5183 return false;
5185 for (fns = lookup_fnfields_slot_nolazy (t, ansi_assopname (NOP_EXPR));
5186 fns; fns = OVL_NEXT (fns))
5188 tree fn = OVL_CURRENT (fns);
5189 if (move_fn_p (fn) && !DECL_ARTIFICIAL (fn))
5190 return true;
5193 return false;
5196 /* Nonzero if we need to build up a constructor call when initializing an
5197 object of this class, either because it has a user-declared constructor
5198 or because it doesn't have a default constructor (so we need to give an
5199 error if no initializer is provided). Use TYPE_NEEDS_CONSTRUCTING when
5200 what you care about is whether or not an object can be produced by a
5201 constructor (e.g. so we don't set TREE_READONLY on const variables of
5202 such type); use this function when what you care about is whether or not
5203 to try to call a constructor to create an object. The latter case is
5204 the former plus some cases of constructors that cannot be called. */
5206 bool
5207 type_build_ctor_call (tree t)
5209 tree inner;
5210 if (TYPE_NEEDS_CONSTRUCTING (t))
5211 return true;
5212 inner = strip_array_types (t);
5213 if (!CLASS_TYPE_P (inner) || ANON_AGGR_TYPE_P (inner))
5214 return false;
5215 if (!TYPE_HAS_DEFAULT_CONSTRUCTOR (inner))
5216 return true;
5217 if (cxx_dialect < cxx11)
5218 return false;
5219 /* A user-declared constructor might be private, and a constructor might
5220 be trivial but deleted. */
5221 for (tree fns = lookup_fnfields_slot (inner, complete_ctor_identifier);
5222 fns; fns = OVL_NEXT (fns))
5224 tree fn = OVL_CURRENT (fns);
5225 if (!DECL_ARTIFICIAL (fn)
5226 || DECL_DELETED_FN (fn))
5227 return true;
5229 return false;
5232 /* Like type_build_ctor_call, but for destructors. */
5234 bool
5235 type_build_dtor_call (tree t)
5237 tree inner;
5238 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
5239 return true;
5240 inner = strip_array_types (t);
5241 if (!CLASS_TYPE_P (inner) || ANON_AGGR_TYPE_P (inner)
5242 || !COMPLETE_TYPE_P (inner))
5243 return false;
5244 if (cxx_dialect < cxx11)
5245 return false;
5246 /* A user-declared destructor might be private, and a destructor might
5247 be trivial but deleted. */
5248 for (tree fns = lookup_fnfields_slot (inner, complete_dtor_identifier);
5249 fns; fns = OVL_NEXT (fns))
5251 tree fn = OVL_CURRENT (fns);
5252 if (!DECL_ARTIFICIAL (fn)
5253 || DECL_DELETED_FN (fn))
5254 return true;
5256 return false;
5259 /* Remove all zero-width bit-fields from T. */
5261 static void
5262 remove_zero_width_bit_fields (tree t)
5264 tree *fieldsp;
5266 fieldsp = &TYPE_FIELDS (t);
5267 while (*fieldsp)
5269 if (TREE_CODE (*fieldsp) == FIELD_DECL
5270 && DECL_C_BIT_FIELD (*fieldsp)
5271 /* We should not be confused by the fact that grokbitfield
5272 temporarily sets the width of the bit field into
5273 DECL_INITIAL (*fieldsp).
5274 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
5275 to that width. */
5276 && integer_zerop (DECL_SIZE (*fieldsp)))
5277 *fieldsp = DECL_CHAIN (*fieldsp);
5278 else
5279 fieldsp = &DECL_CHAIN (*fieldsp);
5283 /* Returns TRUE iff we need a cookie when dynamically allocating an
5284 array whose elements have the indicated class TYPE. */
5286 static bool
5287 type_requires_array_cookie (tree type)
5289 tree fns;
5290 bool has_two_argument_delete_p = false;
5292 gcc_assert (CLASS_TYPE_P (type));
5294 /* If there's a non-trivial destructor, we need a cookie. In order
5295 to iterate through the array calling the destructor for each
5296 element, we'll have to know how many elements there are. */
5297 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
5298 return true;
5300 /* If the usual deallocation function is a two-argument whose second
5301 argument is of type `size_t', then we have to pass the size of
5302 the array to the deallocation function, so we will need to store
5303 a cookie. */
5304 fns = lookup_fnfields (TYPE_BINFO (type),
5305 ansi_opname (VEC_DELETE_EXPR),
5306 /*protect=*/0);
5307 /* If there are no `operator []' members, or the lookup is
5308 ambiguous, then we don't need a cookie. */
5309 if (!fns || fns == error_mark_node)
5310 return false;
5311 /* Loop through all of the functions. */
5312 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
5314 tree fn;
5315 tree second_parm;
5317 /* Select the current function. */
5318 fn = OVL_CURRENT (fns);
5319 /* See if this function is a one-argument delete function. If
5320 it is, then it will be the usual deallocation function. */
5321 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
5322 if (second_parm == void_list_node)
5323 return false;
5324 /* Do not consider this function if its second argument is an
5325 ellipsis. */
5326 if (!second_parm)
5327 continue;
5328 /* Otherwise, if we have a two-argument function and the second
5329 argument is `size_t', it will be the usual deallocation
5330 function -- unless there is one-argument function, too. */
5331 if (TREE_CHAIN (second_parm) == void_list_node
5332 && same_type_p (TREE_VALUE (second_parm), size_type_node))
5333 has_two_argument_delete_p = true;
5336 return has_two_argument_delete_p;
5339 /* Finish computing the `literal type' property of class type T.
5341 At this point, we have already processed base classes and
5342 non-static data members. We need to check whether the copy
5343 constructor is trivial, the destructor is trivial, and there
5344 is a trivial default constructor or at least one constexpr
5345 constructor other than the copy constructor. */
5347 static void
5348 finalize_literal_type_property (tree t)
5350 tree fn;
5352 if (cxx_dialect < cxx11
5353 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
5354 CLASSTYPE_LITERAL_P (t) = false;
5355 else if (CLASSTYPE_LITERAL_P (t) && !TYPE_HAS_TRIVIAL_DFLT (t)
5356 && CLASSTYPE_NON_AGGREGATE (t)
5357 && !TYPE_HAS_CONSTEXPR_CTOR (t))
5358 CLASSTYPE_LITERAL_P (t) = false;
5360 if (!CLASSTYPE_LITERAL_P (t))
5361 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
5362 if (DECL_DECLARED_CONSTEXPR_P (fn)
5363 && TREE_CODE (fn) != TEMPLATE_DECL
5364 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
5365 && !DECL_CONSTRUCTOR_P (fn))
5367 DECL_DECLARED_CONSTEXPR_P (fn) = false;
5368 if (!DECL_GENERATED_P (fn))
5370 error ("enclosing class of constexpr non-static member "
5371 "function %q+#D is not a literal type", fn);
5372 explain_non_literal_class (t);
5377 /* T is a non-literal type used in a context which requires a constant
5378 expression. Explain why it isn't literal. */
5380 void
5381 explain_non_literal_class (tree t)
5383 static struct pointer_set_t *diagnosed;
5385 if (!CLASS_TYPE_P (t))
5386 return;
5387 t = TYPE_MAIN_VARIANT (t);
5389 if (diagnosed == NULL)
5390 diagnosed = pointer_set_create ();
5391 if (pointer_set_insert (diagnosed, t) != 0)
5392 /* Already explained. */
5393 return;
5395 inform (0, "%q+T is not literal because:", t);
5396 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
5397 inform (0, " %q+T has a non-trivial destructor", t);
5398 else if (CLASSTYPE_NON_AGGREGATE (t)
5399 && !TYPE_HAS_TRIVIAL_DFLT (t)
5400 && !TYPE_HAS_CONSTEXPR_CTOR (t))
5402 inform (0, " %q+T is not an aggregate, does not have a trivial "
5403 "default constructor, and has no constexpr constructor that "
5404 "is not a copy or move constructor", t);
5405 if (TYPE_HAS_DEFAULT_CONSTRUCTOR (t)
5406 && !type_has_user_provided_default_constructor (t))
5408 /* Note that we can't simply call locate_ctor because when the
5409 constructor is deleted it just returns NULL_TREE. */
5410 tree fns;
5411 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
5413 tree fn = OVL_CURRENT (fns);
5414 tree parms = TYPE_ARG_TYPES (TREE_TYPE (fn));
5416 parms = skip_artificial_parms_for (fn, parms);
5418 if (sufficient_parms_p (parms))
5420 if (DECL_DELETED_FN (fn))
5421 maybe_explain_implicit_delete (fn);
5422 else
5423 explain_invalid_constexpr_fn (fn);
5424 break;
5429 else
5431 tree binfo, base_binfo, field; int i;
5432 for (binfo = TYPE_BINFO (t), i = 0;
5433 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
5435 tree basetype = TREE_TYPE (base_binfo);
5436 if (!CLASSTYPE_LITERAL_P (basetype))
5438 inform (0, " base class %qT of %q+T is non-literal",
5439 basetype, t);
5440 explain_non_literal_class (basetype);
5441 return;
5444 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5446 tree ftype;
5447 if (TREE_CODE (field) != FIELD_DECL)
5448 continue;
5449 ftype = TREE_TYPE (field);
5450 if (!literal_type_p (ftype))
5452 inform (0, " non-static data member %q+D has "
5453 "non-literal type", field);
5454 if (CLASS_TYPE_P (ftype))
5455 explain_non_literal_class (ftype);
5461 /* Check the validity of the bases and members declared in T. Add any
5462 implicitly-generated functions (like copy-constructors and
5463 assignment operators). Compute various flag bits (like
5464 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
5465 level: i.e., independently of the ABI in use. */
5467 static void
5468 check_bases_and_members (tree t)
5470 /* Nonzero if the implicitly generated copy constructor should take
5471 a non-const reference argument. */
5472 int cant_have_const_ctor;
5473 /* Nonzero if the implicitly generated assignment operator
5474 should take a non-const reference argument. */
5475 int no_const_asn_ref;
5476 tree access_decls;
5477 bool saved_complex_asn_ref;
5478 bool saved_nontrivial_dtor;
5479 tree fn;
5481 /* Pick up any abi_tags from our template arguments before checking. */
5482 inherit_targ_abi_tags (t);
5484 /* By default, we use const reference arguments and generate default
5485 constructors. */
5486 cant_have_const_ctor = 0;
5487 no_const_asn_ref = 0;
5489 /* Check all the base-classes. */
5490 check_bases (t, &cant_have_const_ctor,
5491 &no_const_asn_ref);
5493 /* Deduce noexcept on destructors. This needs to happen after we've set
5494 triviality flags appropriately for our bases. */
5495 if (cxx_dialect >= cxx11)
5496 deduce_noexcept_on_destructors (t);
5498 /* Check all the method declarations. */
5499 check_methods (t);
5501 /* Save the initial values of these flags which only indicate whether
5502 or not the class has user-provided functions. As we analyze the
5503 bases and members we can set these flags for other reasons. */
5504 saved_complex_asn_ref = TYPE_HAS_COMPLEX_COPY_ASSIGN (t);
5505 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
5507 /* Check all the data member declarations. We cannot call
5508 check_field_decls until we have called check_bases check_methods,
5509 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
5510 being set appropriately. */
5511 check_field_decls (t, &access_decls,
5512 &cant_have_const_ctor,
5513 &no_const_asn_ref);
5515 /* A nearly-empty class has to be vptr-containing; a nearly empty
5516 class contains just a vptr. */
5517 if (!TYPE_CONTAINS_VPTR_P (t))
5518 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
5520 /* Do some bookkeeping that will guide the generation of implicitly
5521 declared member functions. */
5522 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
5523 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
5524 /* We need to call a constructor for this class if it has a
5525 user-provided constructor, or if the default constructor is going
5526 to initialize the vptr. (This is not an if-and-only-if;
5527 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
5528 themselves need constructing.) */
5529 TYPE_NEEDS_CONSTRUCTING (t)
5530 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
5531 /* [dcl.init.aggr]
5533 An aggregate is an array or a class with no user-provided
5534 constructors ... and no virtual functions.
5536 Again, other conditions for being an aggregate are checked
5537 elsewhere. */
5538 CLASSTYPE_NON_AGGREGATE (t)
5539 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
5540 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
5541 retain the old definition internally for ABI reasons. */
5542 CLASSTYPE_NON_LAYOUT_POD_P (t)
5543 |= (CLASSTYPE_NON_AGGREGATE (t)
5544 || saved_nontrivial_dtor || saved_complex_asn_ref);
5545 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
5546 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
5547 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
5548 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
5550 /* If the class has no user-declared constructor, but does have
5551 non-static const or reference data members that can never be
5552 initialized, issue a warning. */
5553 if (warn_uninitialized
5554 /* Classes with user-declared constructors are presumed to
5555 initialize these members. */
5556 && !TYPE_HAS_USER_CONSTRUCTOR (t)
5557 /* Aggregates can be initialized with brace-enclosed
5558 initializers. */
5559 && CLASSTYPE_NON_AGGREGATE (t))
5561 tree field;
5563 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5565 tree type;
5567 if (TREE_CODE (field) != FIELD_DECL
5568 || DECL_INITIAL (field) != NULL_TREE)
5569 continue;
5571 type = TREE_TYPE (field);
5572 if (TREE_CODE (type) == REFERENCE_TYPE)
5573 warning (OPT_Wuninitialized, "non-static reference %q+#D "
5574 "in class without a constructor", field);
5575 else if (CP_TYPE_CONST_P (type)
5576 && (!CLASS_TYPE_P (type)
5577 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
5578 warning (OPT_Wuninitialized, "non-static const member %q+#D "
5579 "in class without a constructor", field);
5583 /* Synthesize any needed methods. */
5584 add_implicitly_declared_members (t, &access_decls,
5585 cant_have_const_ctor,
5586 no_const_asn_ref);
5588 /* Check defaulted declarations here so we have cant_have_const_ctor
5589 and don't need to worry about clones. */
5590 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
5591 if (!DECL_ARTIFICIAL (fn) && DECL_DEFAULTED_IN_CLASS_P (fn))
5593 int copy = copy_fn_p (fn);
5594 if (copy > 0)
5596 bool imp_const_p
5597 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
5598 : !no_const_asn_ref);
5599 bool fn_const_p = (copy == 2);
5601 if (fn_const_p && !imp_const_p)
5602 /* If the function is defaulted outside the class, we just
5603 give the synthesis error. */
5604 error ("%q+D declared to take const reference, but implicit "
5605 "declaration would take non-const", fn);
5607 defaulted_late_check (fn);
5610 if (LAMBDA_TYPE_P (t))
5612 /* "The closure type associated with a lambda-expression has a deleted
5613 default constructor and a deleted copy assignment operator." */
5614 TYPE_NEEDS_CONSTRUCTING (t) = 1;
5615 TYPE_HAS_COMPLEX_DFLT (t) = 1;
5616 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
5617 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 0;
5619 /* "This class type is not an aggregate." */
5620 CLASSTYPE_NON_AGGREGATE (t) = 1;
5623 /* Compute the 'literal type' property before we
5624 do anything with non-static member functions. */
5625 finalize_literal_type_property (t);
5627 /* Create the in-charge and not-in-charge variants of constructors
5628 and destructors. */
5629 clone_constructors_and_destructors (t);
5631 /* Process the using-declarations. */
5632 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
5633 handle_using_decl (TREE_VALUE (access_decls), t);
5635 /* Build and sort the CLASSTYPE_METHOD_VEC. */
5636 finish_struct_methods (t);
5638 /* Figure out whether or not we will need a cookie when dynamically
5639 allocating an array of this type. */
5640 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
5641 = type_requires_array_cookie (t);
5644 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
5645 accordingly. If a new vfield was created (because T doesn't have a
5646 primary base class), then the newly created field is returned. It
5647 is not added to the TYPE_FIELDS list; it is the caller's
5648 responsibility to do that. Accumulate declared virtual functions
5649 on VIRTUALS_P. */
5651 static tree
5652 create_vtable_ptr (tree t, tree* virtuals_p)
5654 tree fn;
5656 /* Collect the virtual functions declared in T. */
5657 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
5658 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
5659 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
5661 tree new_virtual = make_node (TREE_LIST);
5663 BV_FN (new_virtual) = fn;
5664 BV_DELTA (new_virtual) = integer_zero_node;
5665 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
5667 TREE_CHAIN (new_virtual) = *virtuals_p;
5668 *virtuals_p = new_virtual;
5671 /* If we couldn't find an appropriate base class, create a new field
5672 here. Even if there weren't any new virtual functions, we might need a
5673 new virtual function table if we're supposed to include vptrs in
5674 all classes that need them. */
5675 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
5677 /* We build this decl with vtbl_ptr_type_node, which is a
5678 `vtable_entry_type*'. It might seem more precise to use
5679 `vtable_entry_type (*)[N]' where N is the number of virtual
5680 functions. However, that would require the vtable pointer in
5681 base classes to have a different type than the vtable pointer
5682 in derived classes. We could make that happen, but that
5683 still wouldn't solve all the problems. In particular, the
5684 type-based alias analysis code would decide that assignments
5685 to the base class vtable pointer can't alias assignments to
5686 the derived class vtable pointer, since they have different
5687 types. Thus, in a derived class destructor, where the base
5688 class constructor was inlined, we could generate bad code for
5689 setting up the vtable pointer.
5691 Therefore, we use one type for all vtable pointers. We still
5692 use a type-correct type; it's just doesn't indicate the array
5693 bounds. That's better than using `void*' or some such; it's
5694 cleaner, and it let's the alias analysis code know that these
5695 stores cannot alias stores to void*! */
5696 tree field;
5698 field = build_decl (input_location,
5699 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
5700 DECL_VIRTUAL_P (field) = 1;
5701 DECL_ARTIFICIAL (field) = 1;
5702 DECL_FIELD_CONTEXT (field) = t;
5703 DECL_FCONTEXT (field) = t;
5704 if (TYPE_PACKED (t))
5705 DECL_PACKED (field) = 1;
5707 TYPE_VFIELD (t) = field;
5709 /* This class is non-empty. */
5710 CLASSTYPE_EMPTY_P (t) = 0;
5712 return field;
5715 return NULL_TREE;
5718 /* Add OFFSET to all base types of BINFO which is a base in the
5719 hierarchy dominated by T.
5721 OFFSET, which is a type offset, is number of bytes. */
5723 static void
5724 propagate_binfo_offsets (tree binfo, tree offset)
5726 int i;
5727 tree primary_binfo;
5728 tree base_binfo;
5730 /* Update BINFO's offset. */
5731 BINFO_OFFSET (binfo)
5732 = convert (sizetype,
5733 size_binop (PLUS_EXPR,
5734 convert (ssizetype, BINFO_OFFSET (binfo)),
5735 offset));
5737 /* Find the primary base class. */
5738 primary_binfo = get_primary_binfo (binfo);
5740 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
5741 propagate_binfo_offsets (primary_binfo, offset);
5743 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
5744 downwards. */
5745 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5747 /* Don't do the primary base twice. */
5748 if (base_binfo == primary_binfo)
5749 continue;
5751 if (BINFO_VIRTUAL_P (base_binfo))
5752 continue;
5754 propagate_binfo_offsets (base_binfo, offset);
5758 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
5759 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
5760 empty subobjects of T. */
5762 static void
5763 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
5765 tree vbase;
5766 tree t = rli->t;
5767 bool first_vbase = true;
5768 tree *next_field;
5770 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
5771 return;
5773 if (!abi_version_at_least(2))
5775 /* In G++ 3.2, we incorrectly rounded the size before laying out
5776 the virtual bases. */
5777 finish_record_layout (rli, /*free_p=*/false);
5778 #ifdef STRUCTURE_SIZE_BOUNDARY
5779 /* Packed structures don't need to have minimum size. */
5780 if (! TYPE_PACKED (t))
5781 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
5782 #endif
5783 rli->offset = TYPE_SIZE_UNIT (t);
5784 rli->bitpos = bitsize_zero_node;
5785 rli->record_align = TYPE_ALIGN (t);
5788 /* Find the last field. The artificial fields created for virtual
5789 bases will go after the last extant field to date. */
5790 next_field = &TYPE_FIELDS (t);
5791 while (*next_field)
5792 next_field = &DECL_CHAIN (*next_field);
5794 /* Go through the virtual bases, allocating space for each virtual
5795 base that is not already a primary base class. These are
5796 allocated in inheritance graph order. */
5797 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
5799 if (!BINFO_VIRTUAL_P (vbase))
5800 continue;
5802 if (!BINFO_PRIMARY_P (vbase))
5804 tree basetype = TREE_TYPE (vbase);
5806 /* This virtual base is not a primary base of any class in the
5807 hierarchy, so we have to add space for it. */
5808 next_field = build_base_field (rli, vbase,
5809 offsets, next_field);
5811 /* If the first virtual base might have been placed at a
5812 lower address, had we started from CLASSTYPE_SIZE, rather
5813 than TYPE_SIZE, issue a warning. There can be both false
5814 positives and false negatives from this warning in rare
5815 cases; to deal with all the possibilities would probably
5816 require performing both layout algorithms and comparing
5817 the results which is not particularly tractable. */
5818 if (warn_abi
5819 && first_vbase
5820 && (tree_int_cst_lt
5821 (size_binop (CEIL_DIV_EXPR,
5822 round_up_loc (input_location,
5823 CLASSTYPE_SIZE (t),
5824 CLASSTYPE_ALIGN (basetype)),
5825 bitsize_unit_node),
5826 BINFO_OFFSET (vbase))))
5827 warning (OPT_Wabi,
5828 "offset of virtual base %qT is not ABI-compliant and "
5829 "may change in a future version of GCC",
5830 basetype);
5832 first_vbase = false;
5837 /* Returns the offset of the byte just past the end of the base class
5838 BINFO. */
5840 static tree
5841 end_of_base (tree binfo)
5843 tree size;
5845 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
5846 size = TYPE_SIZE_UNIT (char_type_node);
5847 else if (is_empty_class (BINFO_TYPE (binfo)))
5848 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
5849 allocate some space for it. It cannot have virtual bases, so
5850 TYPE_SIZE_UNIT is fine. */
5851 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5852 else
5853 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5855 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
5858 /* Returns the offset of the byte just past the end of the base class
5859 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
5860 only non-virtual bases are included. */
5862 static tree
5863 end_of_class (tree t, int include_virtuals_p)
5865 tree result = size_zero_node;
5866 vec<tree, va_gc> *vbases;
5867 tree binfo;
5868 tree base_binfo;
5869 tree offset;
5870 int i;
5872 for (binfo = TYPE_BINFO (t), i = 0;
5873 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5875 if (!include_virtuals_p
5876 && BINFO_VIRTUAL_P (base_binfo)
5877 && (!BINFO_PRIMARY_P (base_binfo)
5878 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
5879 continue;
5881 offset = end_of_base (base_binfo);
5882 if (INT_CST_LT_UNSIGNED (result, offset))
5883 result = offset;
5886 /* G++ 3.2 did not check indirect virtual bases. */
5887 if (abi_version_at_least (2) && include_virtuals_p)
5888 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5889 vec_safe_iterate (vbases, i, &base_binfo); i++)
5891 offset = end_of_base (base_binfo);
5892 if (INT_CST_LT_UNSIGNED (result, offset))
5893 result = offset;
5896 return result;
5899 /* Warn about bases of T that are inaccessible because they are
5900 ambiguous. For example:
5902 struct S {};
5903 struct T : public S {};
5904 struct U : public S, public T {};
5906 Here, `(S*) new U' is not allowed because there are two `S'
5907 subobjects of U. */
5909 static void
5910 warn_about_ambiguous_bases (tree t)
5912 int i;
5913 vec<tree, va_gc> *vbases;
5914 tree basetype;
5915 tree binfo;
5916 tree base_binfo;
5918 /* If there are no repeated bases, nothing can be ambiguous. */
5919 if (!CLASSTYPE_REPEATED_BASE_P (t))
5920 return;
5922 /* Check direct bases. */
5923 for (binfo = TYPE_BINFO (t), i = 0;
5924 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5926 basetype = BINFO_TYPE (base_binfo);
5928 if (!uniquely_derived_from_p (basetype, t))
5929 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
5930 basetype, t);
5933 /* Check for ambiguous virtual bases. */
5934 if (extra_warnings)
5935 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5936 vec_safe_iterate (vbases, i, &binfo); i++)
5938 basetype = BINFO_TYPE (binfo);
5940 if (!uniquely_derived_from_p (basetype, t))
5941 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due "
5942 "to ambiguity", basetype, t);
5946 /* Compare two INTEGER_CSTs K1 and K2. */
5948 static int
5949 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
5951 return tree_int_cst_compare ((tree) k1, (tree) k2);
5954 /* Increase the size indicated in RLI to account for empty classes
5955 that are "off the end" of the class. */
5957 static void
5958 include_empty_classes (record_layout_info rli)
5960 tree eoc;
5961 tree rli_size;
5963 /* It might be the case that we grew the class to allocate a
5964 zero-sized base class. That won't be reflected in RLI, yet,
5965 because we are willing to overlay multiple bases at the same
5966 offset. However, now we need to make sure that RLI is big enough
5967 to reflect the entire class. */
5968 eoc = end_of_class (rli->t,
5969 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
5970 rli_size = rli_size_unit_so_far (rli);
5971 if (TREE_CODE (rli_size) == INTEGER_CST
5972 && INT_CST_LT_UNSIGNED (rli_size, eoc))
5974 if (!abi_version_at_least (2))
5975 /* In version 1 of the ABI, the size of a class that ends with
5976 a bitfield was not rounded up to a whole multiple of a
5977 byte. Because rli_size_unit_so_far returns only the number
5978 of fully allocated bytes, any extra bits were not included
5979 in the size. */
5980 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
5981 else
5982 /* The size should have been rounded to a whole byte. */
5983 gcc_assert (tree_int_cst_equal
5984 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
5985 rli->bitpos
5986 = size_binop (PLUS_EXPR,
5987 rli->bitpos,
5988 size_binop (MULT_EXPR,
5989 convert (bitsizetype,
5990 size_binop (MINUS_EXPR,
5991 eoc, rli_size)),
5992 bitsize_int (BITS_PER_UNIT)));
5993 normalize_rli (rli);
5997 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
5998 BINFO_OFFSETs for all of the base-classes. Position the vtable
5999 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
6001 static void
6002 layout_class_type (tree t, tree *virtuals_p)
6004 tree non_static_data_members;
6005 tree field;
6006 tree vptr;
6007 record_layout_info rli;
6008 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
6009 types that appear at that offset. */
6010 splay_tree empty_base_offsets;
6011 /* True if the last field laid out was a bit-field. */
6012 bool last_field_was_bitfield = false;
6013 /* The location at which the next field should be inserted. */
6014 tree *next_field;
6015 /* T, as a base class. */
6016 tree base_t;
6018 /* Keep track of the first non-static data member. */
6019 non_static_data_members = TYPE_FIELDS (t);
6021 /* Start laying out the record. */
6022 rli = start_record_layout (t);
6024 /* Mark all the primary bases in the hierarchy. */
6025 determine_primary_bases (t);
6027 /* Create a pointer to our virtual function table. */
6028 vptr = create_vtable_ptr (t, virtuals_p);
6030 /* The vptr is always the first thing in the class. */
6031 if (vptr)
6033 DECL_CHAIN (vptr) = TYPE_FIELDS (t);
6034 TYPE_FIELDS (t) = vptr;
6035 next_field = &DECL_CHAIN (vptr);
6036 place_field (rli, vptr);
6038 else
6039 next_field = &TYPE_FIELDS (t);
6041 /* Build FIELD_DECLs for all of the non-virtual base-types. */
6042 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
6043 NULL, NULL);
6044 build_base_fields (rli, empty_base_offsets, next_field);
6046 /* Layout the non-static data members. */
6047 for (field = non_static_data_members; field; field = DECL_CHAIN (field))
6049 tree type;
6050 tree padding;
6052 /* We still pass things that aren't non-static data members to
6053 the back end, in case it wants to do something with them. */
6054 if (TREE_CODE (field) != FIELD_DECL)
6056 place_field (rli, field);
6057 /* If the static data member has incomplete type, keep track
6058 of it so that it can be completed later. (The handling
6059 of pending statics in finish_record_layout is
6060 insufficient; consider:
6062 struct S1;
6063 struct S2 { static S1 s1; };
6065 At this point, finish_record_layout will be called, but
6066 S1 is still incomplete.) */
6067 if (VAR_P (field))
6069 maybe_register_incomplete_var (field);
6070 /* The visibility of static data members is determined
6071 at their point of declaration, not their point of
6072 definition. */
6073 determine_visibility (field);
6075 continue;
6078 type = TREE_TYPE (field);
6079 if (type == error_mark_node)
6080 continue;
6082 padding = NULL_TREE;
6084 /* If this field is a bit-field whose width is greater than its
6085 type, then there are some special rules for allocating
6086 it. */
6087 if (DECL_C_BIT_FIELD (field)
6088 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
6090 unsigned int itk;
6091 tree integer_type;
6092 bool was_unnamed_p = false;
6093 /* We must allocate the bits as if suitably aligned for the
6094 longest integer type that fits in this many bits. type
6095 of the field. Then, we are supposed to use the left over
6096 bits as additional padding. */
6097 for (itk = itk_char; itk != itk_none; ++itk)
6098 if (integer_types[itk] != NULL_TREE
6099 && (INT_CST_LT (size_int (MAX_FIXED_MODE_SIZE),
6100 TYPE_SIZE (integer_types[itk]))
6101 || INT_CST_LT (DECL_SIZE (field),
6102 TYPE_SIZE (integer_types[itk]))))
6103 break;
6105 /* ITK now indicates a type that is too large for the
6106 field. We have to back up by one to find the largest
6107 type that fits. */
6110 --itk;
6111 integer_type = integer_types[itk];
6112 } while (itk > 0 && integer_type == NULL_TREE);
6114 /* Figure out how much additional padding is required. GCC
6115 3.2 always created a padding field, even if it had zero
6116 width. */
6117 if (!abi_version_at_least (2)
6118 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
6120 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
6121 /* In a union, the padding field must have the full width
6122 of the bit-field; all fields start at offset zero. */
6123 padding = DECL_SIZE (field);
6124 else
6126 if (TREE_CODE (t) == UNION_TYPE)
6127 warning (OPT_Wabi, "size assigned to %qT may not be "
6128 "ABI-compliant and may change in a future "
6129 "version of GCC",
6131 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
6132 TYPE_SIZE (integer_type));
6135 #ifdef PCC_BITFIELD_TYPE_MATTERS
6136 /* An unnamed bitfield does not normally affect the
6137 alignment of the containing class on a target where
6138 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
6139 make any exceptions for unnamed bitfields when the
6140 bitfields are longer than their types. Therefore, we
6141 temporarily give the field a name. */
6142 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
6144 was_unnamed_p = true;
6145 DECL_NAME (field) = make_anon_name ();
6147 #endif
6148 DECL_SIZE (field) = TYPE_SIZE (integer_type);
6149 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
6150 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
6151 layout_nonempty_base_or_field (rli, field, NULL_TREE,
6152 empty_base_offsets);
6153 if (was_unnamed_p)
6154 DECL_NAME (field) = NULL_TREE;
6155 /* Now that layout has been performed, set the size of the
6156 field to the size of its declared type; the rest of the
6157 field is effectively invisible. */
6158 DECL_SIZE (field) = TYPE_SIZE (type);
6159 /* We must also reset the DECL_MODE of the field. */
6160 if (abi_version_at_least (2))
6161 DECL_MODE (field) = TYPE_MODE (type);
6162 else if (warn_abi
6163 && DECL_MODE (field) != TYPE_MODE (type))
6164 /* Versions of G++ before G++ 3.4 did not reset the
6165 DECL_MODE. */
6166 warning (OPT_Wabi,
6167 "the offset of %qD may not be ABI-compliant and may "
6168 "change in a future version of GCC", field);
6170 else
6171 layout_nonempty_base_or_field (rli, field, NULL_TREE,
6172 empty_base_offsets);
6174 /* Remember the location of any empty classes in FIELD. */
6175 if (abi_version_at_least (2))
6176 record_subobject_offsets (TREE_TYPE (field),
6177 byte_position(field),
6178 empty_base_offsets,
6179 /*is_data_member=*/true);
6181 /* If a bit-field does not immediately follow another bit-field,
6182 and yet it starts in the middle of a byte, we have failed to
6183 comply with the ABI. */
6184 if (warn_abi
6185 && DECL_C_BIT_FIELD (field)
6186 /* The TREE_NO_WARNING flag gets set by Objective-C when
6187 laying out an Objective-C class. The ObjC ABI differs
6188 from the C++ ABI, and so we do not want a warning
6189 here. */
6190 && !TREE_NO_WARNING (field)
6191 && !last_field_was_bitfield
6192 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
6193 DECL_FIELD_BIT_OFFSET (field),
6194 bitsize_unit_node)))
6195 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
6196 "change in a future version of GCC", field);
6198 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
6199 offset of the field. */
6200 if (warn_abi
6201 && !abi_version_at_least (2)
6202 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
6203 byte_position (field))
6204 && contains_empty_class_p (TREE_TYPE (field)))
6205 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
6206 "classes to be placed at different locations in a "
6207 "future version of GCC", field);
6209 /* The middle end uses the type of expressions to determine the
6210 possible range of expression values. In order to optimize
6211 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
6212 must be made aware of the width of "i", via its type.
6214 Because C++ does not have integer types of arbitrary width,
6215 we must (for the purposes of the front end) convert from the
6216 type assigned here to the declared type of the bitfield
6217 whenever a bitfield expression is used as an rvalue.
6218 Similarly, when assigning a value to a bitfield, the value
6219 must be converted to the type given the bitfield here. */
6220 if (DECL_C_BIT_FIELD (field))
6222 unsigned HOST_WIDE_INT width;
6223 tree ftype = TREE_TYPE (field);
6224 width = tree_to_uhwi (DECL_SIZE (field));
6225 if (width != TYPE_PRECISION (ftype))
6227 TREE_TYPE (field)
6228 = c_build_bitfield_integer_type (width,
6229 TYPE_UNSIGNED (ftype));
6230 TREE_TYPE (field)
6231 = cp_build_qualified_type (TREE_TYPE (field),
6232 cp_type_quals (ftype));
6236 /* If we needed additional padding after this field, add it
6237 now. */
6238 if (padding)
6240 tree padding_field;
6242 padding_field = build_decl (input_location,
6243 FIELD_DECL,
6244 NULL_TREE,
6245 char_type_node);
6246 DECL_BIT_FIELD (padding_field) = 1;
6247 DECL_SIZE (padding_field) = padding;
6248 DECL_CONTEXT (padding_field) = t;
6249 DECL_ARTIFICIAL (padding_field) = 1;
6250 DECL_IGNORED_P (padding_field) = 1;
6251 layout_nonempty_base_or_field (rli, padding_field,
6252 NULL_TREE,
6253 empty_base_offsets);
6256 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
6259 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
6261 /* Make sure that we are on a byte boundary so that the size of
6262 the class without virtual bases will always be a round number
6263 of bytes. */
6264 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
6265 normalize_rli (rli);
6268 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
6269 padding. */
6270 if (!abi_version_at_least (2))
6271 include_empty_classes(rli);
6273 /* Delete all zero-width bit-fields from the list of fields. Now
6274 that the type is laid out they are no longer important. */
6275 remove_zero_width_bit_fields (t);
6277 /* Create the version of T used for virtual bases. We do not use
6278 make_class_type for this version; this is an artificial type. For
6279 a POD type, we just reuse T. */
6280 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
6282 base_t = make_node (TREE_CODE (t));
6284 /* Set the size and alignment for the new type. In G++ 3.2, all
6285 empty classes were considered to have size zero when used as
6286 base classes. */
6287 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
6289 TYPE_SIZE (base_t) = bitsize_zero_node;
6290 TYPE_SIZE_UNIT (base_t) = size_zero_node;
6291 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
6292 warning (OPT_Wabi,
6293 "layout of classes derived from empty class %qT "
6294 "may change in a future version of GCC",
6297 else
6299 tree eoc;
6301 /* If the ABI version is not at least two, and the last
6302 field was a bit-field, RLI may not be on a byte
6303 boundary. In particular, rli_size_unit_so_far might
6304 indicate the last complete byte, while rli_size_so_far
6305 indicates the total number of bits used. Therefore,
6306 rli_size_so_far, rather than rli_size_unit_so_far, is
6307 used to compute TYPE_SIZE_UNIT. */
6308 eoc = end_of_class (t, /*include_virtuals_p=*/0);
6309 TYPE_SIZE_UNIT (base_t)
6310 = size_binop (MAX_EXPR,
6311 convert (sizetype,
6312 size_binop (CEIL_DIV_EXPR,
6313 rli_size_so_far (rli),
6314 bitsize_int (BITS_PER_UNIT))),
6315 eoc);
6316 TYPE_SIZE (base_t)
6317 = size_binop (MAX_EXPR,
6318 rli_size_so_far (rli),
6319 size_binop (MULT_EXPR,
6320 convert (bitsizetype, eoc),
6321 bitsize_int (BITS_PER_UNIT)));
6323 TYPE_ALIGN (base_t) = rli->record_align;
6324 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
6326 /* Copy the fields from T. */
6327 next_field = &TYPE_FIELDS (base_t);
6328 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
6329 if (TREE_CODE (field) == FIELD_DECL)
6331 *next_field = build_decl (input_location,
6332 FIELD_DECL,
6333 DECL_NAME (field),
6334 TREE_TYPE (field));
6335 DECL_CONTEXT (*next_field) = base_t;
6336 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
6337 DECL_FIELD_BIT_OFFSET (*next_field)
6338 = DECL_FIELD_BIT_OFFSET (field);
6339 DECL_SIZE (*next_field) = DECL_SIZE (field);
6340 DECL_MODE (*next_field) = DECL_MODE (field);
6341 next_field = &DECL_CHAIN (*next_field);
6344 /* Record the base version of the type. */
6345 CLASSTYPE_AS_BASE (t) = base_t;
6346 TYPE_CONTEXT (base_t) = t;
6348 else
6349 CLASSTYPE_AS_BASE (t) = t;
6351 /* Every empty class contains an empty class. */
6352 if (CLASSTYPE_EMPTY_P (t))
6353 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
6355 /* Set the TYPE_DECL for this type to contain the right
6356 value for DECL_OFFSET, so that we can use it as part
6357 of a COMPONENT_REF for multiple inheritance. */
6358 layout_decl (TYPE_MAIN_DECL (t), 0);
6360 /* Now fix up any virtual base class types that we left lying
6361 around. We must get these done before we try to lay out the
6362 virtual function table. As a side-effect, this will remove the
6363 base subobject fields. */
6364 layout_virtual_bases (rli, empty_base_offsets);
6366 /* Make sure that empty classes are reflected in RLI at this
6367 point. */
6368 include_empty_classes(rli);
6370 /* Make sure not to create any structures with zero size. */
6371 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
6372 place_field (rli,
6373 build_decl (input_location,
6374 FIELD_DECL, NULL_TREE, char_type_node));
6376 /* If this is a non-POD, declaring it packed makes a difference to how it
6377 can be used as a field; don't let finalize_record_size undo it. */
6378 if (TYPE_PACKED (t) && !layout_pod_type_p (t))
6379 rli->packed_maybe_necessary = true;
6381 /* Let the back end lay out the type. */
6382 finish_record_layout (rli, /*free_p=*/true);
6384 if (TYPE_SIZE_UNIT (t)
6385 && TREE_CODE (TYPE_SIZE_UNIT (t)) == INTEGER_CST
6386 && !TREE_OVERFLOW (TYPE_SIZE_UNIT (t))
6387 && !valid_constant_size_p (TYPE_SIZE_UNIT (t)))
6388 error ("type %qT is too large", t);
6390 /* Warn about bases that can't be talked about due to ambiguity. */
6391 warn_about_ambiguous_bases (t);
6393 /* Now that we're done with layout, give the base fields the real types. */
6394 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
6395 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
6396 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
6398 /* Clean up. */
6399 splay_tree_delete (empty_base_offsets);
6401 if (CLASSTYPE_EMPTY_P (t)
6402 && tree_int_cst_lt (sizeof_biggest_empty_class,
6403 TYPE_SIZE_UNIT (t)))
6404 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
6407 /* Determine the "key method" for the class type indicated by TYPE,
6408 and set CLASSTYPE_KEY_METHOD accordingly. */
6410 void
6411 determine_key_method (tree type)
6413 tree method;
6415 if (TYPE_FOR_JAVA (type)
6416 || processing_template_decl
6417 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
6418 || CLASSTYPE_INTERFACE_KNOWN (type))
6419 return;
6421 /* The key method is the first non-pure virtual function that is not
6422 inline at the point of class definition. On some targets the
6423 key function may not be inline; those targets should not call
6424 this function until the end of the translation unit. */
6425 for (method = TYPE_METHODS (type); method != NULL_TREE;
6426 method = DECL_CHAIN (method))
6427 if (DECL_VINDEX (method) != NULL_TREE
6428 && ! DECL_DECLARED_INLINE_P (method)
6429 && ! DECL_PURE_VIRTUAL_P (method))
6431 CLASSTYPE_KEY_METHOD (type) = method;
6432 break;
6435 return;
6439 /* Allocate and return an instance of struct sorted_fields_type with
6440 N fields. */
6442 static struct sorted_fields_type *
6443 sorted_fields_type_new (int n)
6445 struct sorted_fields_type *sft;
6446 sft = ggc_alloc_sorted_fields_type (sizeof (struct sorted_fields_type)
6447 + n * sizeof (tree));
6448 sft->len = n;
6450 return sft;
6454 /* Perform processing required when the definition of T (a class type)
6455 is complete. */
6457 void
6458 finish_struct_1 (tree t)
6460 tree x;
6461 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
6462 tree virtuals = NULL_TREE;
6464 if (COMPLETE_TYPE_P (t))
6466 gcc_assert (MAYBE_CLASS_TYPE_P (t));
6467 error ("redefinition of %q#T", t);
6468 popclass ();
6469 return;
6472 /* If this type was previously laid out as a forward reference,
6473 make sure we lay it out again. */
6474 TYPE_SIZE (t) = NULL_TREE;
6475 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
6477 /* Make assumptions about the class; we'll reset the flags if
6478 necessary. */
6479 CLASSTYPE_EMPTY_P (t) = 1;
6480 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
6481 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
6482 CLASSTYPE_LITERAL_P (t) = true;
6484 /* Do end-of-class semantic processing: checking the validity of the
6485 bases and members and add implicitly generated methods. */
6486 check_bases_and_members (t);
6488 /* Find the key method. */
6489 if (TYPE_CONTAINS_VPTR_P (t))
6491 /* The Itanium C++ ABI permits the key method to be chosen when
6492 the class is defined -- even though the key method so
6493 selected may later turn out to be an inline function. On
6494 some systems (such as ARM Symbian OS) the key method cannot
6495 be determined until the end of the translation unit. On such
6496 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
6497 will cause the class to be added to KEYED_CLASSES. Then, in
6498 finish_file we will determine the key method. */
6499 if (targetm.cxx.key_method_may_be_inline ())
6500 determine_key_method (t);
6502 /* If a polymorphic class has no key method, we may emit the vtable
6503 in every translation unit where the class definition appears. */
6504 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
6505 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
6508 /* Layout the class itself. */
6509 layout_class_type (t, &virtuals);
6510 if (CLASSTYPE_AS_BASE (t) != t)
6511 /* We use the base type for trivial assignments, and hence it
6512 needs a mode. */
6513 compute_record_mode (CLASSTYPE_AS_BASE (t));
6515 virtuals = modify_all_vtables (t, nreverse (virtuals));
6517 /* If necessary, create the primary vtable for this class. */
6518 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
6520 /* We must enter these virtuals into the table. */
6521 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
6522 build_primary_vtable (NULL_TREE, t);
6523 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
6524 /* Here we know enough to change the type of our virtual
6525 function table, but we will wait until later this function. */
6526 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
6528 /* If we're warning about ABI tags, check the types of the new
6529 virtual functions. */
6530 if (warn_abi_tag)
6531 for (tree v = virtuals; v; v = TREE_CHAIN (v))
6532 check_abi_tags (t, TREE_VALUE (v));
6535 if (TYPE_CONTAINS_VPTR_P (t))
6537 int vindex;
6538 tree fn;
6540 if (BINFO_VTABLE (TYPE_BINFO (t)))
6541 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
6542 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
6543 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
6545 /* Add entries for virtual functions introduced by this class. */
6546 BINFO_VIRTUALS (TYPE_BINFO (t))
6547 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
6549 /* Set DECL_VINDEX for all functions declared in this class. */
6550 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
6552 fn = TREE_CHAIN (fn),
6553 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
6554 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
6556 tree fndecl = BV_FN (fn);
6558 if (DECL_THUNK_P (fndecl))
6559 /* A thunk. We should never be calling this entry directly
6560 from this vtable -- we'd use the entry for the non
6561 thunk base function. */
6562 DECL_VINDEX (fndecl) = NULL_TREE;
6563 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
6564 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
6568 finish_struct_bits (t);
6569 set_method_tm_attributes (t);
6571 /* Complete the rtl for any static member objects of the type we're
6572 working on. */
6573 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
6574 if (VAR_P (x) && TREE_STATIC (x)
6575 && TREE_TYPE (x) != error_mark_node
6576 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
6577 DECL_MODE (x) = TYPE_MODE (t);
6579 /* Done with FIELDS...now decide whether to sort these for
6580 faster lookups later.
6582 We use a small number because most searches fail (succeeding
6583 ultimately as the search bores through the inheritance
6584 hierarchy), and we want this failure to occur quickly. */
6586 insert_into_classtype_sorted_fields (TYPE_FIELDS (t), t, 8);
6588 /* Complain if one of the field types requires lower visibility. */
6589 constrain_class_visibility (t);
6591 /* Make the rtl for any new vtables we have created, and unmark
6592 the base types we marked. */
6593 finish_vtbls (t);
6595 /* Build the VTT for T. */
6596 build_vtt (t);
6598 /* This warning does not make sense for Java classes, since they
6599 cannot have destructors. */
6600 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
6602 tree dtor;
6604 dtor = CLASSTYPE_DESTRUCTORS (t);
6605 if (/* An implicitly declared destructor is always public. And,
6606 if it were virtual, we would have created it by now. */
6607 !dtor
6608 || (!DECL_VINDEX (dtor)
6609 && (/* public non-virtual */
6610 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
6611 || (/* non-public non-virtual with friends */
6612 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
6613 && (CLASSTYPE_FRIEND_CLASSES (t)
6614 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
6615 warning (OPT_Wnon_virtual_dtor,
6616 "%q#T has virtual functions and accessible"
6617 " non-virtual destructor", t);
6620 complete_vars (t);
6622 if (warn_overloaded_virtual)
6623 warn_hidden (t);
6625 /* Class layout, assignment of virtual table slots, etc., is now
6626 complete. Give the back end a chance to tweak the visibility of
6627 the class or perform any other required target modifications. */
6628 targetm.cxx.adjust_class_at_definition (t);
6630 maybe_suppress_debug_info (t);
6632 if (flag_vtable_verify)
6633 vtv_save_class_info (t);
6635 dump_class_hierarchy (t);
6637 /* Finish debugging output for this type. */
6638 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
6640 if (TYPE_TRANSPARENT_AGGR (t))
6642 tree field = first_field (t);
6643 if (field == NULL_TREE || error_operand_p (field))
6645 error ("type transparent %q#T does not have any fields", t);
6646 TYPE_TRANSPARENT_AGGR (t) = 0;
6648 else if (DECL_ARTIFICIAL (field))
6650 if (DECL_FIELD_IS_BASE (field))
6651 error ("type transparent class %qT has base classes", t);
6652 else
6654 gcc_checking_assert (DECL_VIRTUAL_P (field));
6655 error ("type transparent class %qT has virtual functions", t);
6657 TYPE_TRANSPARENT_AGGR (t) = 0;
6659 else if (TYPE_MODE (t) != DECL_MODE (field))
6661 error ("type transparent %q#T cannot be made transparent because "
6662 "the type of the first field has a different ABI from the "
6663 "class overall", t);
6664 TYPE_TRANSPARENT_AGGR (t) = 0;
6669 /* Insert FIELDS into T for the sorted case if the FIELDS count is
6670 equal to THRESHOLD or greater than THRESHOLD. */
6672 static void
6673 insert_into_classtype_sorted_fields (tree fields, tree t, int threshold)
6675 int n_fields = count_fields (fields);
6676 if (n_fields >= threshold)
6678 struct sorted_fields_type *field_vec = sorted_fields_type_new (n_fields);
6679 add_fields_to_record_type (fields, field_vec, 0);
6680 qsort (field_vec->elts, n_fields, sizeof (tree), field_decl_cmp);
6681 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
6685 /* Insert lately defined enum ENUMTYPE into T for the sorted case. */
6687 void
6688 insert_late_enum_def_into_classtype_sorted_fields (tree enumtype, tree t)
6690 struct sorted_fields_type *sorted_fields = CLASSTYPE_SORTED_FIELDS (t);
6691 if (sorted_fields)
6693 int i;
6694 int n_fields
6695 = list_length (TYPE_VALUES (enumtype)) + sorted_fields->len;
6696 struct sorted_fields_type *field_vec = sorted_fields_type_new (n_fields);
6698 for (i = 0; i < sorted_fields->len; ++i)
6699 field_vec->elts[i] = sorted_fields->elts[i];
6701 add_enum_fields_to_record_type (enumtype, field_vec,
6702 sorted_fields->len);
6703 qsort (field_vec->elts, n_fields, sizeof (tree), field_decl_cmp);
6704 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
6708 /* When T was built up, the member declarations were added in reverse
6709 order. Rearrange them to declaration order. */
6711 void
6712 unreverse_member_declarations (tree t)
6714 tree next;
6715 tree prev;
6716 tree x;
6718 /* The following lists are all in reverse order. Put them in
6719 declaration order now. */
6720 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
6721 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
6723 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
6724 reverse order, so we can't just use nreverse. */
6725 prev = NULL_TREE;
6726 for (x = TYPE_FIELDS (t);
6727 x && TREE_CODE (x) != TYPE_DECL;
6728 x = next)
6730 next = DECL_CHAIN (x);
6731 DECL_CHAIN (x) = prev;
6732 prev = x;
6734 if (prev)
6736 DECL_CHAIN (TYPE_FIELDS (t)) = x;
6737 if (prev)
6738 TYPE_FIELDS (t) = prev;
6742 tree
6743 finish_struct (tree t, tree attributes)
6745 location_t saved_loc = input_location;
6747 /* Now that we've got all the field declarations, reverse everything
6748 as necessary. */
6749 unreverse_member_declarations (t);
6751 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
6753 /* Nadger the current location so that diagnostics point to the start of
6754 the struct, not the end. */
6755 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
6757 if (processing_template_decl)
6759 tree x;
6761 finish_struct_methods (t);
6762 TYPE_SIZE (t) = bitsize_zero_node;
6763 TYPE_SIZE_UNIT (t) = size_zero_node;
6765 /* We need to emit an error message if this type was used as a parameter
6766 and it is an abstract type, even if it is a template. We construct
6767 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
6768 account and we call complete_vars with this type, which will check
6769 the PARM_DECLS. Note that while the type is being defined,
6770 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
6771 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
6772 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
6773 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
6774 if (DECL_PURE_VIRTUAL_P (x))
6775 vec_safe_push (CLASSTYPE_PURE_VIRTUALS (t), x);
6776 complete_vars (t);
6777 /* We need to add the target functions to the CLASSTYPE_METHOD_VEC if
6778 an enclosing scope is a template class, so that this function be
6779 found by lookup_fnfields_1 when the using declaration is not
6780 instantiated yet. */
6781 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
6782 if (TREE_CODE (x) == USING_DECL)
6784 tree fn = strip_using_decl (x);
6785 if (is_overloaded_fn (fn))
6786 for (; fn; fn = OVL_NEXT (fn))
6787 add_method (t, OVL_CURRENT (fn), x);
6790 /* Remember current #pragma pack value. */
6791 TYPE_PRECISION (t) = maximum_field_alignment;
6793 /* Fix up any variants we've already built. */
6794 for (x = TYPE_NEXT_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
6796 TYPE_SIZE (x) = TYPE_SIZE (t);
6797 TYPE_SIZE_UNIT (x) = TYPE_SIZE_UNIT (t);
6798 TYPE_FIELDS (x) = TYPE_FIELDS (t);
6799 TYPE_METHODS (x) = TYPE_METHODS (t);
6802 else
6803 finish_struct_1 (t);
6805 input_location = saved_loc;
6807 TYPE_BEING_DEFINED (t) = 0;
6809 if (current_class_type)
6810 popclass ();
6811 else
6812 error ("trying to finish struct, but kicked out due to previous parse errors");
6814 if (processing_template_decl && at_function_scope_p ()
6815 /* Lambdas are defined by the LAMBDA_EXPR. */
6816 && !LAMBDA_TYPE_P (t))
6817 add_stmt (build_min (TAG_DEFN, t));
6819 return t;
6822 /* Hash table to avoid endless recursion when handling references. */
6823 static hash_table <pointer_hash <tree_node> > fixed_type_or_null_ref_ht;
6825 /* Return the dynamic type of INSTANCE, if known.
6826 Used to determine whether the virtual function table is needed
6827 or not.
6829 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6830 of our knowledge of its type. *NONNULL should be initialized
6831 before this function is called. */
6833 static tree
6834 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
6836 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
6838 switch (TREE_CODE (instance))
6840 case INDIRECT_REF:
6841 if (POINTER_TYPE_P (TREE_TYPE (instance)))
6842 return NULL_TREE;
6843 else
6844 return RECUR (TREE_OPERAND (instance, 0));
6846 case CALL_EXPR:
6847 /* This is a call to a constructor, hence it's never zero. */
6848 if (TREE_HAS_CONSTRUCTOR (instance))
6850 if (nonnull)
6851 *nonnull = 1;
6852 return TREE_TYPE (instance);
6854 return NULL_TREE;
6856 case SAVE_EXPR:
6857 /* This is a call to a constructor, hence it's never zero. */
6858 if (TREE_HAS_CONSTRUCTOR (instance))
6860 if (nonnull)
6861 *nonnull = 1;
6862 return TREE_TYPE (instance);
6864 return RECUR (TREE_OPERAND (instance, 0));
6866 case POINTER_PLUS_EXPR:
6867 case PLUS_EXPR:
6868 case MINUS_EXPR:
6869 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
6870 return RECUR (TREE_OPERAND (instance, 0));
6871 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
6872 /* Propagate nonnull. */
6873 return RECUR (TREE_OPERAND (instance, 0));
6875 return NULL_TREE;
6877 CASE_CONVERT:
6878 return RECUR (TREE_OPERAND (instance, 0));
6880 case ADDR_EXPR:
6881 instance = TREE_OPERAND (instance, 0);
6882 if (nonnull)
6884 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
6885 with a real object -- given &p->f, p can still be null. */
6886 tree t = get_base_address (instance);
6887 /* ??? Probably should check DECL_WEAK here. */
6888 if (t && DECL_P (t))
6889 *nonnull = 1;
6891 return RECUR (instance);
6893 case COMPONENT_REF:
6894 /* If this component is really a base class reference, then the field
6895 itself isn't definitive. */
6896 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
6897 return RECUR (TREE_OPERAND (instance, 0));
6898 return RECUR (TREE_OPERAND (instance, 1));
6900 case VAR_DECL:
6901 case FIELD_DECL:
6902 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
6903 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
6905 if (nonnull)
6906 *nonnull = 1;
6907 return TREE_TYPE (TREE_TYPE (instance));
6909 /* fall through... */
6910 case TARGET_EXPR:
6911 case PARM_DECL:
6912 case RESULT_DECL:
6913 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
6915 if (nonnull)
6916 *nonnull = 1;
6917 return TREE_TYPE (instance);
6919 else if (instance == current_class_ptr)
6921 if (nonnull)
6922 *nonnull = 1;
6924 /* if we're in a ctor or dtor, we know our type. If
6925 current_class_ptr is set but we aren't in a function, we're in
6926 an NSDMI (and therefore a constructor). */
6927 if (current_scope () != current_function_decl
6928 || (DECL_LANG_SPECIFIC (current_function_decl)
6929 && (DECL_CONSTRUCTOR_P (current_function_decl)
6930 || DECL_DESTRUCTOR_P (current_function_decl))))
6932 if (cdtorp)
6933 *cdtorp = 1;
6934 return TREE_TYPE (TREE_TYPE (instance));
6937 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
6939 /* We only need one hash table because it is always left empty. */
6940 if (!fixed_type_or_null_ref_ht.is_created ())
6941 fixed_type_or_null_ref_ht.create (37);
6943 /* Reference variables should be references to objects. */
6944 if (nonnull)
6945 *nonnull = 1;
6947 /* Enter the INSTANCE in a table to prevent recursion; a
6948 variable's initializer may refer to the variable
6949 itself. */
6950 if (VAR_P (instance)
6951 && DECL_INITIAL (instance)
6952 && !type_dependent_expression_p_push (DECL_INITIAL (instance))
6953 && !fixed_type_or_null_ref_ht.find (instance))
6955 tree type;
6956 tree_node **slot;
6958 slot = fixed_type_or_null_ref_ht.find_slot (instance, INSERT);
6959 *slot = instance;
6960 type = RECUR (DECL_INITIAL (instance));
6961 fixed_type_or_null_ref_ht.remove_elt (instance);
6963 return type;
6966 return NULL_TREE;
6968 default:
6969 return NULL_TREE;
6971 #undef RECUR
6974 /* Return nonzero if the dynamic type of INSTANCE is known, and
6975 equivalent to the static type. We also handle the case where
6976 INSTANCE is really a pointer. Return negative if this is a
6977 ctor/dtor. There the dynamic type is known, but this might not be
6978 the most derived base of the original object, and hence virtual
6979 bases may not be laid out according to this type.
6981 Used to determine whether the virtual function table is needed
6982 or not.
6984 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6985 of our knowledge of its type. *NONNULL should be initialized
6986 before this function is called. */
6989 resolves_to_fixed_type_p (tree instance, int* nonnull)
6991 tree t = TREE_TYPE (instance);
6992 int cdtorp = 0;
6993 tree fixed;
6995 /* processing_template_decl can be false in a template if we're in
6996 fold_non_dependent_expr, but we still want to suppress this check. */
6997 if (in_template_function ())
6999 /* In a template we only care about the type of the result. */
7000 if (nonnull)
7001 *nonnull = true;
7002 return true;
7005 fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
7006 if (fixed == NULL_TREE)
7007 return 0;
7008 if (POINTER_TYPE_P (t))
7009 t = TREE_TYPE (t);
7010 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
7011 return 0;
7012 return cdtorp ? -1 : 1;
7016 void
7017 init_class_processing (void)
7019 current_class_depth = 0;
7020 current_class_stack_size = 10;
7021 current_class_stack
7022 = XNEWVEC (struct class_stack_node, current_class_stack_size);
7023 vec_alloc (local_classes, 8);
7024 sizeof_biggest_empty_class = size_zero_node;
7026 ridpointers[(int) RID_PUBLIC] = access_public_node;
7027 ridpointers[(int) RID_PRIVATE] = access_private_node;
7028 ridpointers[(int) RID_PROTECTED] = access_protected_node;
7031 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
7033 static void
7034 restore_class_cache (void)
7036 tree type;
7038 /* We are re-entering the same class we just left, so we don't
7039 have to search the whole inheritance matrix to find all the
7040 decls to bind again. Instead, we install the cached
7041 class_shadowed list and walk through it binding names. */
7042 push_binding_level (previous_class_level);
7043 class_binding_level = previous_class_level;
7044 /* Restore IDENTIFIER_TYPE_VALUE. */
7045 for (type = class_binding_level->type_shadowed;
7046 type;
7047 type = TREE_CHAIN (type))
7048 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
7051 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
7052 appropriate for TYPE.
7054 So that we may avoid calls to lookup_name, we cache the _TYPE
7055 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
7057 For multiple inheritance, we perform a two-pass depth-first search
7058 of the type lattice. */
7060 void
7061 pushclass (tree type)
7063 class_stack_node_t csn;
7065 type = TYPE_MAIN_VARIANT (type);
7067 /* Make sure there is enough room for the new entry on the stack. */
7068 if (current_class_depth + 1 >= current_class_stack_size)
7070 current_class_stack_size *= 2;
7071 current_class_stack
7072 = XRESIZEVEC (struct class_stack_node, current_class_stack,
7073 current_class_stack_size);
7076 /* Insert a new entry on the class stack. */
7077 csn = current_class_stack + current_class_depth;
7078 csn->name = current_class_name;
7079 csn->type = current_class_type;
7080 csn->access = current_access_specifier;
7081 csn->names_used = 0;
7082 csn->hidden = 0;
7083 current_class_depth++;
7085 /* Now set up the new type. */
7086 current_class_name = TYPE_NAME (type);
7087 if (TREE_CODE (current_class_name) == TYPE_DECL)
7088 current_class_name = DECL_NAME (current_class_name);
7089 current_class_type = type;
7091 /* By default, things in classes are private, while things in
7092 structures or unions are public. */
7093 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
7094 ? access_private_node
7095 : access_public_node);
7097 if (previous_class_level
7098 && type != previous_class_level->this_entity
7099 && current_class_depth == 1)
7101 /* Forcibly remove any old class remnants. */
7102 invalidate_class_lookup_cache ();
7105 if (!previous_class_level
7106 || type != previous_class_level->this_entity
7107 || current_class_depth > 1)
7108 pushlevel_class ();
7109 else
7110 restore_class_cache ();
7113 /* When we exit a toplevel class scope, we save its binding level so
7114 that we can restore it quickly. Here, we've entered some other
7115 class, so we must invalidate our cache. */
7117 void
7118 invalidate_class_lookup_cache (void)
7120 previous_class_level = NULL;
7123 /* Get out of the current class scope. If we were in a class scope
7124 previously, that is the one popped to. */
7126 void
7127 popclass (void)
7129 poplevel_class ();
7131 current_class_depth--;
7132 current_class_name = current_class_stack[current_class_depth].name;
7133 current_class_type = current_class_stack[current_class_depth].type;
7134 current_access_specifier = current_class_stack[current_class_depth].access;
7135 if (current_class_stack[current_class_depth].names_used)
7136 splay_tree_delete (current_class_stack[current_class_depth].names_used);
7139 /* Mark the top of the class stack as hidden. */
7141 void
7142 push_class_stack (void)
7144 if (current_class_depth)
7145 ++current_class_stack[current_class_depth - 1].hidden;
7148 /* Mark the top of the class stack as un-hidden. */
7150 void
7151 pop_class_stack (void)
7153 if (current_class_depth)
7154 --current_class_stack[current_class_depth - 1].hidden;
7157 /* Returns 1 if the class type currently being defined is either T or
7158 a nested type of T. */
7160 bool
7161 currently_open_class (tree t)
7163 int i;
7165 if (!CLASS_TYPE_P (t))
7166 return false;
7168 t = TYPE_MAIN_VARIANT (t);
7170 /* We start looking from 1 because entry 0 is from global scope,
7171 and has no type. */
7172 for (i = current_class_depth; i > 0; --i)
7174 tree c;
7175 if (i == current_class_depth)
7176 c = current_class_type;
7177 else
7179 if (current_class_stack[i].hidden)
7180 break;
7181 c = current_class_stack[i].type;
7183 if (!c)
7184 continue;
7185 if (same_type_p (c, t))
7186 return true;
7188 return false;
7191 /* If either current_class_type or one of its enclosing classes are derived
7192 from T, return the appropriate type. Used to determine how we found
7193 something via unqualified lookup. */
7195 tree
7196 currently_open_derived_class (tree t)
7198 int i;
7200 /* The bases of a dependent type are unknown. */
7201 if (dependent_type_p (t))
7202 return NULL_TREE;
7204 if (!current_class_type)
7205 return NULL_TREE;
7207 if (DERIVED_FROM_P (t, current_class_type))
7208 return current_class_type;
7210 for (i = current_class_depth - 1; i > 0; --i)
7212 if (current_class_stack[i].hidden)
7213 break;
7214 if (DERIVED_FROM_P (t, current_class_stack[i].type))
7215 return current_class_stack[i].type;
7218 return NULL_TREE;
7221 /* Returns the innermost class type which is not a lambda closure type. */
7223 tree
7224 current_nonlambda_class_type (void)
7226 int i;
7228 /* We start looking from 1 because entry 0 is from global scope,
7229 and has no type. */
7230 for (i = current_class_depth; i > 0; --i)
7232 tree c;
7233 if (i == current_class_depth)
7234 c = current_class_type;
7235 else
7237 if (current_class_stack[i].hidden)
7238 break;
7239 c = current_class_stack[i].type;
7241 if (!c)
7242 continue;
7243 if (!LAMBDA_TYPE_P (c))
7244 return c;
7246 return NULL_TREE;
7249 /* When entering a class scope, all enclosing class scopes' names with
7250 static meaning (static variables, static functions, types and
7251 enumerators) have to be visible. This recursive function calls
7252 pushclass for all enclosing class contexts until global or a local
7253 scope is reached. TYPE is the enclosed class. */
7255 void
7256 push_nested_class (tree type)
7258 /* A namespace might be passed in error cases, like A::B:C. */
7259 if (type == NULL_TREE
7260 || !CLASS_TYPE_P (type))
7261 return;
7263 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
7265 pushclass (type);
7268 /* Undoes a push_nested_class call. */
7270 void
7271 pop_nested_class (void)
7273 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
7275 popclass ();
7276 if (context && CLASS_TYPE_P (context))
7277 pop_nested_class ();
7280 /* Returns the number of extern "LANG" blocks we are nested within. */
7283 current_lang_depth (void)
7285 return vec_safe_length (current_lang_base);
7288 /* Set global variables CURRENT_LANG_NAME to appropriate value
7289 so that behavior of name-mangling machinery is correct. */
7291 void
7292 push_lang_context (tree name)
7294 vec_safe_push (current_lang_base, current_lang_name);
7296 if (name == lang_name_cplusplus)
7298 current_lang_name = name;
7300 else if (name == lang_name_java)
7302 current_lang_name = name;
7303 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
7304 (See record_builtin_java_type in decl.c.) However, that causes
7305 incorrect debug entries if these types are actually used.
7306 So we re-enable debug output after extern "Java". */
7307 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
7308 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
7309 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
7310 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
7311 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
7312 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
7313 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
7314 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
7316 else if (name == lang_name_c)
7318 current_lang_name = name;
7320 else
7321 error ("language string %<\"%E\"%> not recognized", name);
7324 /* Get out of the current language scope. */
7326 void
7327 pop_lang_context (void)
7329 current_lang_name = current_lang_base->pop ();
7332 /* Type instantiation routines. */
7334 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
7335 matches the TARGET_TYPE. If there is no satisfactory match, return
7336 error_mark_node, and issue an error & warning messages under
7337 control of FLAGS. Permit pointers to member function if FLAGS
7338 permits. If TEMPLATE_ONLY, the name of the overloaded function was
7339 a template-id, and EXPLICIT_TARGS are the explicitly provided
7340 template arguments.
7342 If OVERLOAD is for one or more member functions, then ACCESS_PATH
7343 is the base path used to reference those member functions. If
7344 the address is resolved to a member function, access checks will be
7345 performed and errors issued if appropriate. */
7347 static tree
7348 resolve_address_of_overloaded_function (tree target_type,
7349 tree overload,
7350 tsubst_flags_t flags,
7351 bool template_only,
7352 tree explicit_targs,
7353 tree access_path)
7355 /* Here's what the standard says:
7357 [over.over]
7359 If the name is a function template, template argument deduction
7360 is done, and if the argument deduction succeeds, the deduced
7361 arguments are used to generate a single template function, which
7362 is added to the set of overloaded functions considered.
7364 Non-member functions and static member functions match targets of
7365 type "pointer-to-function" or "reference-to-function." Nonstatic
7366 member functions match targets of type "pointer-to-member
7367 function;" the function type of the pointer to member is used to
7368 select the member function from the set of overloaded member
7369 functions. If a nonstatic member function is selected, the
7370 reference to the overloaded function name is required to have the
7371 form of a pointer to member as described in 5.3.1.
7373 If more than one function is selected, any template functions in
7374 the set are eliminated if the set also contains a non-template
7375 function, and any given template function is eliminated if the
7376 set contains a second template function that is more specialized
7377 than the first according to the partial ordering rules 14.5.5.2.
7378 After such eliminations, if any, there shall remain exactly one
7379 selected function. */
7381 int is_ptrmem = 0;
7382 /* We store the matches in a TREE_LIST rooted here. The functions
7383 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
7384 interoperability with most_specialized_instantiation. */
7385 tree matches = NULL_TREE;
7386 tree fn;
7387 tree target_fn_type;
7389 /* By the time we get here, we should be seeing only real
7390 pointer-to-member types, not the internal POINTER_TYPE to
7391 METHOD_TYPE representation. */
7392 gcc_assert (!TYPE_PTR_P (target_type)
7393 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
7395 gcc_assert (is_overloaded_fn (overload));
7397 /* Check that the TARGET_TYPE is reasonable. */
7398 if (TYPE_PTRFN_P (target_type)
7399 || TYPE_REFFN_P (target_type))
7400 /* This is OK. */;
7401 else if (TYPE_PTRMEMFUNC_P (target_type))
7402 /* This is OK, too. */
7403 is_ptrmem = 1;
7404 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
7405 /* This is OK, too. This comes from a conversion to reference
7406 type. */
7407 target_type = build_reference_type (target_type);
7408 else
7410 if (flags & tf_error)
7411 error ("cannot resolve overloaded function %qD based on"
7412 " conversion to type %qT",
7413 DECL_NAME (OVL_FUNCTION (overload)), target_type);
7414 return error_mark_node;
7417 /* Non-member functions and static member functions match targets of type
7418 "pointer-to-function" or "reference-to-function." Nonstatic member
7419 functions match targets of type "pointer-to-member-function;" the
7420 function type of the pointer to member is used to select the member
7421 function from the set of overloaded member functions.
7423 So figure out the FUNCTION_TYPE that we want to match against. */
7424 target_fn_type = static_fn_type (target_type);
7426 /* If we can find a non-template function that matches, we can just
7427 use it. There's no point in generating template instantiations
7428 if we're just going to throw them out anyhow. But, of course, we
7429 can only do this when we don't *need* a template function. */
7430 if (!template_only)
7432 tree fns;
7434 for (fns = overload; fns; fns = OVL_NEXT (fns))
7436 tree fn = OVL_CURRENT (fns);
7438 if (TREE_CODE (fn) == TEMPLATE_DECL)
7439 /* We're not looking for templates just yet. */
7440 continue;
7442 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
7443 != is_ptrmem)
7444 /* We're looking for a non-static member, and this isn't
7445 one, or vice versa. */
7446 continue;
7448 /* Ignore functions which haven't been explicitly
7449 declared. */
7450 if (DECL_ANTICIPATED (fn))
7451 continue;
7453 /* See if there's a match. */
7454 if (same_type_p (target_fn_type, static_fn_type (fn)))
7455 matches = tree_cons (fn, NULL_TREE, matches);
7459 /* Now, if we've already got a match (or matches), there's no need
7460 to proceed to the template functions. But, if we don't have a
7461 match we need to look at them, too. */
7462 if (!matches)
7464 tree target_arg_types;
7465 tree target_ret_type;
7466 tree fns;
7467 tree *args;
7468 unsigned int nargs, ia;
7469 tree arg;
7471 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
7472 target_ret_type = TREE_TYPE (target_fn_type);
7474 nargs = list_length (target_arg_types);
7475 args = XALLOCAVEC (tree, nargs);
7476 for (arg = target_arg_types, ia = 0;
7477 arg != NULL_TREE && arg != void_list_node;
7478 arg = TREE_CHAIN (arg), ++ia)
7479 args[ia] = TREE_VALUE (arg);
7480 nargs = ia;
7482 for (fns = overload; fns; fns = OVL_NEXT (fns))
7484 tree fn = OVL_CURRENT (fns);
7485 tree instantiation;
7486 tree targs;
7488 if (TREE_CODE (fn) != TEMPLATE_DECL)
7489 /* We're only looking for templates. */
7490 continue;
7492 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
7493 != is_ptrmem)
7494 /* We're not looking for a non-static member, and this is
7495 one, or vice versa. */
7496 continue;
7498 tree ret = target_ret_type;
7500 /* If the template has a deduced return type, don't expose it to
7501 template argument deduction. */
7502 if (undeduced_auto_decl (fn))
7503 ret = NULL_TREE;
7505 /* Try to do argument deduction. */
7506 targs = make_tree_vec (DECL_NTPARMS (fn));
7507 instantiation = fn_type_unification (fn, explicit_targs, targs, args,
7508 nargs, ret,
7509 DEDUCE_EXACT, LOOKUP_NORMAL,
7510 false, false);
7511 if (instantiation == error_mark_node)
7512 /* Instantiation failed. */
7513 continue;
7515 /* And now force instantiation to do return type deduction. */
7516 if (undeduced_auto_decl (instantiation))
7518 ++function_depth;
7519 instantiate_decl (instantiation, /*defer*/false, /*class*/false);
7520 --function_depth;
7522 require_deduced_type (instantiation);
7525 /* See if there's a match. */
7526 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
7527 matches = tree_cons (instantiation, fn, matches);
7530 /* Now, remove all but the most specialized of the matches. */
7531 if (matches)
7533 tree match = most_specialized_instantiation (matches);
7535 if (match != error_mark_node)
7536 matches = tree_cons (TREE_PURPOSE (match),
7537 NULL_TREE,
7538 NULL_TREE);
7542 /* Now we should have exactly one function in MATCHES. */
7543 if (matches == NULL_TREE)
7545 /* There were *no* matches. */
7546 if (flags & tf_error)
7548 error ("no matches converting function %qD to type %q#T",
7549 DECL_NAME (OVL_CURRENT (overload)),
7550 target_type);
7552 print_candidates (overload);
7554 return error_mark_node;
7556 else if (TREE_CHAIN (matches))
7558 /* There were too many matches. First check if they're all
7559 the same function. */
7560 tree match = NULL_TREE;
7562 fn = TREE_PURPOSE (matches);
7564 /* For multi-versioned functions, more than one match is just fine and
7565 decls_match will return false as they are different. */
7566 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
7567 if (!decls_match (fn, TREE_PURPOSE (match))
7568 && !targetm.target_option.function_versions
7569 (fn, TREE_PURPOSE (match)))
7570 break;
7572 if (match)
7574 if (flags & tf_error)
7576 error ("converting overloaded function %qD to type %q#T is ambiguous",
7577 DECL_NAME (OVL_FUNCTION (overload)),
7578 target_type);
7580 /* Since print_candidates expects the functions in the
7581 TREE_VALUE slot, we flip them here. */
7582 for (match = matches; match; match = TREE_CHAIN (match))
7583 TREE_VALUE (match) = TREE_PURPOSE (match);
7585 print_candidates (matches);
7588 return error_mark_node;
7592 /* Good, exactly one match. Now, convert it to the correct type. */
7593 fn = TREE_PURPOSE (matches);
7595 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
7596 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
7598 static int explained;
7600 if (!(flags & tf_error))
7601 return error_mark_node;
7603 permerror (input_location, "assuming pointer to member %qD", fn);
7604 if (!explained)
7606 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
7607 explained = 1;
7611 /* If a pointer to a function that is multi-versioned is requested, the
7612 pointer to the dispatcher function is returned instead. This works
7613 well because indirectly calling the function will dispatch the right
7614 function version at run-time. */
7615 if (DECL_FUNCTION_VERSIONED (fn))
7617 fn = get_function_version_dispatcher (fn);
7618 if (fn == NULL)
7619 return error_mark_node;
7620 /* Mark all the versions corresponding to the dispatcher as used. */
7621 if (!(flags & tf_conv))
7622 mark_versions_used (fn);
7625 /* If we're doing overload resolution purely for the purpose of
7626 determining conversion sequences, we should not consider the
7627 function used. If this conversion sequence is selected, the
7628 function will be marked as used at this point. */
7629 if (!(flags & tf_conv))
7631 /* Make =delete work with SFINAE. */
7632 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
7633 return error_mark_node;
7635 mark_used (fn);
7638 /* We could not check access to member functions when this
7639 expression was originally created since we did not know at that
7640 time to which function the expression referred. */
7641 if (DECL_FUNCTION_MEMBER_P (fn))
7643 gcc_assert (access_path);
7644 perform_or_defer_access_check (access_path, fn, fn, flags);
7647 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
7648 return cp_build_addr_expr (fn, flags);
7649 else
7651 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
7652 will mark the function as addressed, but here we must do it
7653 explicitly. */
7654 cxx_mark_addressable (fn);
7656 return fn;
7660 /* This function will instantiate the type of the expression given in
7661 RHS to match the type of LHSTYPE. If errors exist, then return
7662 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
7663 we complain on errors. If we are not complaining, never modify rhs,
7664 as overload resolution wants to try many possible instantiations, in
7665 the hope that at least one will work.
7667 For non-recursive calls, LHSTYPE should be a function, pointer to
7668 function, or a pointer to member function. */
7670 tree
7671 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
7673 tsubst_flags_t flags_in = flags;
7674 tree access_path = NULL_TREE;
7676 flags &= ~tf_ptrmem_ok;
7678 if (lhstype == unknown_type_node)
7680 if (flags & tf_error)
7681 error ("not enough type information");
7682 return error_mark_node;
7685 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
7687 tree fntype = non_reference (lhstype);
7688 if (same_type_p (fntype, TREE_TYPE (rhs)))
7689 return rhs;
7690 if (flag_ms_extensions
7691 && TYPE_PTRMEMFUNC_P (fntype)
7692 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
7693 /* Microsoft allows `A::f' to be resolved to a
7694 pointer-to-member. */
7696 else
7698 if (flags & tf_error)
7699 error ("cannot convert %qE from type %qT to type %qT",
7700 rhs, TREE_TYPE (rhs), fntype);
7701 return error_mark_node;
7705 if (BASELINK_P (rhs))
7707 access_path = BASELINK_ACCESS_BINFO (rhs);
7708 rhs = BASELINK_FUNCTIONS (rhs);
7711 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
7712 deduce any type information. */
7713 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
7715 if (flags & tf_error)
7716 error ("not enough type information");
7717 return error_mark_node;
7720 /* There only a few kinds of expressions that may have a type
7721 dependent on overload resolution. */
7722 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
7723 || TREE_CODE (rhs) == COMPONENT_REF
7724 || is_overloaded_fn (rhs)
7725 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
7727 /* This should really only be used when attempting to distinguish
7728 what sort of a pointer to function we have. For now, any
7729 arithmetic operation which is not supported on pointers
7730 is rejected as an error. */
7732 switch (TREE_CODE (rhs))
7734 case COMPONENT_REF:
7736 tree member = TREE_OPERAND (rhs, 1);
7738 member = instantiate_type (lhstype, member, flags);
7739 if (member != error_mark_node
7740 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
7741 /* Do not lose object's side effects. */
7742 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
7743 TREE_OPERAND (rhs, 0), member);
7744 return member;
7747 case OFFSET_REF:
7748 rhs = TREE_OPERAND (rhs, 1);
7749 if (BASELINK_P (rhs))
7750 return instantiate_type (lhstype, rhs, flags_in);
7752 /* This can happen if we are forming a pointer-to-member for a
7753 member template. */
7754 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
7756 /* Fall through. */
7758 case TEMPLATE_ID_EXPR:
7760 tree fns = TREE_OPERAND (rhs, 0);
7761 tree args = TREE_OPERAND (rhs, 1);
7763 return
7764 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
7765 /*template_only=*/true,
7766 args, access_path);
7769 case OVERLOAD:
7770 case FUNCTION_DECL:
7771 return
7772 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
7773 /*template_only=*/false,
7774 /*explicit_targs=*/NULL_TREE,
7775 access_path);
7777 case ADDR_EXPR:
7779 if (PTRMEM_OK_P (rhs))
7780 flags |= tf_ptrmem_ok;
7782 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
7785 case ERROR_MARK:
7786 return error_mark_node;
7788 default:
7789 gcc_unreachable ();
7791 return error_mark_node;
7794 /* Return the name of the virtual function pointer field
7795 (as an IDENTIFIER_NODE) for the given TYPE. Note that
7796 this may have to look back through base types to find the
7797 ultimate field name. (For single inheritance, these could
7798 all be the same name. Who knows for multiple inheritance). */
7800 static tree
7801 get_vfield_name (tree type)
7803 tree binfo, base_binfo;
7804 char *buf;
7806 for (binfo = TYPE_BINFO (type);
7807 BINFO_N_BASE_BINFOS (binfo);
7808 binfo = base_binfo)
7810 base_binfo = BINFO_BASE_BINFO (binfo, 0);
7812 if (BINFO_VIRTUAL_P (base_binfo)
7813 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
7814 break;
7817 type = BINFO_TYPE (binfo);
7818 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
7819 + TYPE_NAME_LENGTH (type) + 2);
7820 sprintf (buf, VFIELD_NAME_FORMAT,
7821 IDENTIFIER_POINTER (constructor_name (type)));
7822 return get_identifier (buf);
7825 void
7826 print_class_statistics (void)
7828 if (! GATHER_STATISTICS)
7829 return;
7831 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
7832 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
7833 if (n_vtables)
7835 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
7836 n_vtables, n_vtable_searches);
7837 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
7838 n_vtable_entries, n_vtable_elems);
7842 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
7843 according to [class]:
7844 The class-name is also inserted
7845 into the scope of the class itself. For purposes of access checking,
7846 the inserted class name is treated as if it were a public member name. */
7848 void
7849 build_self_reference (void)
7851 tree name = constructor_name (current_class_type);
7852 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
7853 tree saved_cas;
7855 DECL_NONLOCAL (value) = 1;
7856 DECL_CONTEXT (value) = current_class_type;
7857 DECL_ARTIFICIAL (value) = 1;
7858 SET_DECL_SELF_REFERENCE_P (value);
7859 set_underlying_type (value);
7861 if (processing_template_decl)
7862 value = push_template_decl (value);
7864 saved_cas = current_access_specifier;
7865 current_access_specifier = access_public_node;
7866 finish_member_declaration (value);
7867 current_access_specifier = saved_cas;
7870 /* Returns 1 if TYPE contains only padding bytes. */
7873 is_empty_class (tree type)
7875 if (type == error_mark_node)
7876 return 0;
7878 if (! CLASS_TYPE_P (type))
7879 return 0;
7881 /* In G++ 3.2, whether or not a class was empty was determined by
7882 looking at its size. */
7883 if (abi_version_at_least (2))
7884 return CLASSTYPE_EMPTY_P (type);
7885 else
7886 return integer_zerop (CLASSTYPE_SIZE (type));
7889 /* Returns true if TYPE contains an empty class. */
7891 static bool
7892 contains_empty_class_p (tree type)
7894 if (is_empty_class (type))
7895 return true;
7896 if (CLASS_TYPE_P (type))
7898 tree field;
7899 tree binfo;
7900 tree base_binfo;
7901 int i;
7903 for (binfo = TYPE_BINFO (type), i = 0;
7904 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7905 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
7906 return true;
7907 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
7908 if (TREE_CODE (field) == FIELD_DECL
7909 && !DECL_ARTIFICIAL (field)
7910 && is_empty_class (TREE_TYPE (field)))
7911 return true;
7913 else if (TREE_CODE (type) == ARRAY_TYPE)
7914 return contains_empty_class_p (TREE_TYPE (type));
7915 return false;
7918 /* Returns true if TYPE contains no actual data, just various
7919 possible combinations of empty classes and possibly a vptr. */
7921 bool
7922 is_really_empty_class (tree type)
7924 if (CLASS_TYPE_P (type))
7926 tree field;
7927 tree binfo;
7928 tree base_binfo;
7929 int i;
7931 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
7932 out, but we'd like to be able to check this before then. */
7933 if (COMPLETE_TYPE_P (type) && is_empty_class (type))
7934 return true;
7936 for (binfo = TYPE_BINFO (type), i = 0;
7937 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7938 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
7939 return false;
7940 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
7941 if (TREE_CODE (field) == FIELD_DECL
7942 && !DECL_ARTIFICIAL (field)
7943 && !is_really_empty_class (TREE_TYPE (field)))
7944 return false;
7945 return true;
7947 else if (TREE_CODE (type) == ARRAY_TYPE)
7948 return is_really_empty_class (TREE_TYPE (type));
7949 return false;
7952 /* Note that NAME was looked up while the current class was being
7953 defined and that the result of that lookup was DECL. */
7955 void
7956 maybe_note_name_used_in_class (tree name, tree decl)
7958 splay_tree names_used;
7960 /* If we're not defining a class, there's nothing to do. */
7961 if (!(innermost_scope_kind() == sk_class
7962 && TYPE_BEING_DEFINED (current_class_type)
7963 && !LAMBDA_TYPE_P (current_class_type)))
7964 return;
7966 /* If there's already a binding for this NAME, then we don't have
7967 anything to worry about. */
7968 if (lookup_member (current_class_type, name,
7969 /*protect=*/0, /*want_type=*/false, tf_warning_or_error))
7970 return;
7972 if (!current_class_stack[current_class_depth - 1].names_used)
7973 current_class_stack[current_class_depth - 1].names_used
7974 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
7975 names_used = current_class_stack[current_class_depth - 1].names_used;
7977 splay_tree_insert (names_used,
7978 (splay_tree_key) name,
7979 (splay_tree_value) decl);
7982 /* Note that NAME was declared (as DECL) in the current class. Check
7983 to see that the declaration is valid. */
7985 void
7986 note_name_declared_in_class (tree name, tree decl)
7988 splay_tree names_used;
7989 splay_tree_node n;
7991 /* Look to see if we ever used this name. */
7992 names_used
7993 = current_class_stack[current_class_depth - 1].names_used;
7994 if (!names_used)
7995 return;
7996 /* The C language allows members to be declared with a type of the same
7997 name, and the C++ standard says this diagnostic is not required. So
7998 allow it in extern "C" blocks unless predantic is specified.
7999 Allow it in all cases if -ms-extensions is specified. */
8000 if ((!pedantic && current_lang_name == lang_name_c)
8001 || flag_ms_extensions)
8002 return;
8003 n = splay_tree_lookup (names_used, (splay_tree_key) name);
8004 if (n)
8006 /* [basic.scope.class]
8008 A name N used in a class S shall refer to the same declaration
8009 in its context and when re-evaluated in the completed scope of
8010 S. */
8011 permerror (input_location, "declaration of %q#D", decl);
8012 permerror (input_location, "changes meaning of %qD from %q+#D",
8013 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
8017 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
8018 Secondary vtables are merged with primary vtables; this function
8019 will return the VAR_DECL for the primary vtable. */
8021 tree
8022 get_vtbl_decl_for_binfo (tree binfo)
8024 tree decl;
8026 decl = BINFO_VTABLE (binfo);
8027 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
8029 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
8030 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
8032 if (decl)
8033 gcc_assert (VAR_P (decl));
8034 return decl;
8038 /* Returns the binfo for the primary base of BINFO. If the resulting
8039 BINFO is a virtual base, and it is inherited elsewhere in the
8040 hierarchy, then the returned binfo might not be the primary base of
8041 BINFO in the complete object. Check BINFO_PRIMARY_P or
8042 BINFO_LOST_PRIMARY_P to be sure. */
8044 static tree
8045 get_primary_binfo (tree binfo)
8047 tree primary_base;
8049 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
8050 if (!primary_base)
8051 return NULL_TREE;
8053 return copied_binfo (primary_base, binfo);
8056 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
8058 static int
8059 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
8061 if (!indented_p)
8062 fprintf (stream, "%*s", indent, "");
8063 return 1;
8066 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
8067 INDENT should be zero when called from the top level; it is
8068 incremented recursively. IGO indicates the next expected BINFO in
8069 inheritance graph ordering. */
8071 static tree
8072 dump_class_hierarchy_r (FILE *stream,
8073 int flags,
8074 tree binfo,
8075 tree igo,
8076 int indent)
8078 int indented = 0;
8079 tree base_binfo;
8080 int i;
8082 indented = maybe_indent_hierarchy (stream, indent, 0);
8083 fprintf (stream, "%s (0x" HOST_WIDE_INT_PRINT_HEX ") ",
8084 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
8085 (HOST_WIDE_INT) (uintptr_t) binfo);
8086 if (binfo != igo)
8088 fprintf (stream, "alternative-path\n");
8089 return igo;
8091 igo = TREE_CHAIN (binfo);
8093 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
8094 tree_to_shwi (BINFO_OFFSET (binfo)));
8095 if (is_empty_class (BINFO_TYPE (binfo)))
8096 fprintf (stream, " empty");
8097 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
8098 fprintf (stream, " nearly-empty");
8099 if (BINFO_VIRTUAL_P (binfo))
8100 fprintf (stream, " virtual");
8101 fprintf (stream, "\n");
8103 indented = 0;
8104 if (BINFO_PRIMARY_P (binfo))
8106 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8107 fprintf (stream, " primary-for %s (0x" HOST_WIDE_INT_PRINT_HEX ")",
8108 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
8109 TFF_PLAIN_IDENTIFIER),
8110 (HOST_WIDE_INT) (uintptr_t) BINFO_INHERITANCE_CHAIN (binfo));
8112 if (BINFO_LOST_PRIMARY_P (binfo))
8114 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8115 fprintf (stream, " lost-primary");
8117 if (indented)
8118 fprintf (stream, "\n");
8120 if (!(flags & TDF_SLIM))
8122 int indented = 0;
8124 if (BINFO_SUBVTT_INDEX (binfo))
8126 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8127 fprintf (stream, " subvttidx=%s",
8128 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
8129 TFF_PLAIN_IDENTIFIER));
8131 if (BINFO_VPTR_INDEX (binfo))
8133 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8134 fprintf (stream, " vptridx=%s",
8135 expr_as_string (BINFO_VPTR_INDEX (binfo),
8136 TFF_PLAIN_IDENTIFIER));
8138 if (BINFO_VPTR_FIELD (binfo))
8140 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8141 fprintf (stream, " vbaseoffset=%s",
8142 expr_as_string (BINFO_VPTR_FIELD (binfo),
8143 TFF_PLAIN_IDENTIFIER));
8145 if (BINFO_VTABLE (binfo))
8147 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
8148 fprintf (stream, " vptr=%s",
8149 expr_as_string (BINFO_VTABLE (binfo),
8150 TFF_PLAIN_IDENTIFIER));
8153 if (indented)
8154 fprintf (stream, "\n");
8157 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
8158 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
8160 return igo;
8163 /* Dump the BINFO hierarchy for T. */
8165 static void
8166 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
8168 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
8169 fprintf (stream, " size=%lu align=%lu\n",
8170 (unsigned long)(tree_to_shwi (TYPE_SIZE (t)) / BITS_PER_UNIT),
8171 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
8172 fprintf (stream, " base size=%lu base align=%lu\n",
8173 (unsigned long)(tree_to_shwi (TYPE_SIZE (CLASSTYPE_AS_BASE (t)))
8174 / BITS_PER_UNIT),
8175 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
8176 / BITS_PER_UNIT));
8177 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
8178 fprintf (stream, "\n");
8181 /* Debug interface to hierarchy dumping. */
8183 void
8184 debug_class (tree t)
8186 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
8189 static void
8190 dump_class_hierarchy (tree t)
8192 int flags;
8193 FILE *stream = dump_begin (TDI_class, &flags);
8195 if (stream)
8197 dump_class_hierarchy_1 (stream, flags, t);
8198 dump_end (TDI_class, stream);
8202 static void
8203 dump_array (FILE * stream, tree decl)
8205 tree value;
8206 unsigned HOST_WIDE_INT ix;
8207 HOST_WIDE_INT elt;
8208 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
8210 elt = (tree_to_shwi (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))))
8211 / BITS_PER_UNIT);
8212 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
8213 fprintf (stream, " %s entries",
8214 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
8215 TFF_PLAIN_IDENTIFIER));
8216 fprintf (stream, "\n");
8218 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
8219 ix, value)
8220 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
8221 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
8224 static void
8225 dump_vtable (tree t, tree binfo, tree vtable)
8227 int flags;
8228 FILE *stream = dump_begin (TDI_class, &flags);
8230 if (!stream)
8231 return;
8233 if (!(flags & TDF_SLIM))
8235 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
8237 fprintf (stream, "%s for %s",
8238 ctor_vtbl_p ? "Construction vtable" : "Vtable",
8239 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
8240 if (ctor_vtbl_p)
8242 if (!BINFO_VIRTUAL_P (binfo))
8243 fprintf (stream, " (0x" HOST_WIDE_INT_PRINT_HEX " instance)",
8244 (HOST_WIDE_INT) (uintptr_t) binfo);
8245 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
8247 fprintf (stream, "\n");
8248 dump_array (stream, vtable);
8249 fprintf (stream, "\n");
8252 dump_end (TDI_class, stream);
8255 static void
8256 dump_vtt (tree t, tree vtt)
8258 int flags;
8259 FILE *stream = dump_begin (TDI_class, &flags);
8261 if (!stream)
8262 return;
8264 if (!(flags & TDF_SLIM))
8266 fprintf (stream, "VTT for %s\n",
8267 type_as_string (t, TFF_PLAIN_IDENTIFIER));
8268 dump_array (stream, vtt);
8269 fprintf (stream, "\n");
8272 dump_end (TDI_class, stream);
8275 /* Dump a function or thunk and its thunkees. */
8277 static void
8278 dump_thunk (FILE *stream, int indent, tree thunk)
8280 static const char spaces[] = " ";
8281 tree name = DECL_NAME (thunk);
8282 tree thunks;
8284 fprintf (stream, "%.*s%p %s %s", indent, spaces,
8285 (void *)thunk,
8286 !DECL_THUNK_P (thunk) ? "function"
8287 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
8288 name ? IDENTIFIER_POINTER (name) : "<unset>");
8289 if (DECL_THUNK_P (thunk))
8291 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
8292 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
8294 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
8295 if (!virtual_adjust)
8296 /*NOP*/;
8297 else if (DECL_THIS_THUNK_P (thunk))
8298 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
8299 tree_to_shwi (virtual_adjust));
8300 else
8301 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
8302 tree_to_shwi (BINFO_VPTR_FIELD (virtual_adjust)),
8303 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
8304 if (THUNK_ALIAS (thunk))
8305 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
8307 fprintf (stream, "\n");
8308 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
8309 dump_thunk (stream, indent + 2, thunks);
8312 /* Dump the thunks for FN. */
8314 void
8315 debug_thunks (tree fn)
8317 dump_thunk (stderr, 0, fn);
8320 /* Virtual function table initialization. */
8322 /* Create all the necessary vtables for T and its base classes. */
8324 static void
8325 finish_vtbls (tree t)
8327 tree vbase;
8328 vec<constructor_elt, va_gc> *v = NULL;
8329 tree vtable = BINFO_VTABLE (TYPE_BINFO (t));
8331 /* We lay out the primary and secondary vtables in one contiguous
8332 vtable. The primary vtable is first, followed by the non-virtual
8333 secondary vtables in inheritance graph order. */
8334 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t),
8335 vtable, t, &v);
8337 /* Then come the virtual bases, also in inheritance graph order. */
8338 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
8340 if (!BINFO_VIRTUAL_P (vbase))
8341 continue;
8342 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), vtable, t, &v);
8345 if (BINFO_VTABLE (TYPE_BINFO (t)))
8346 initialize_vtable (TYPE_BINFO (t), v);
8349 /* Initialize the vtable for BINFO with the INITS. */
8351 static void
8352 initialize_vtable (tree binfo, vec<constructor_elt, va_gc> *inits)
8354 tree decl;
8356 layout_vtable_decl (binfo, vec_safe_length (inits));
8357 decl = get_vtbl_decl_for_binfo (binfo);
8358 initialize_artificial_var (decl, inits);
8359 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
8362 /* Build the VTT (virtual table table) for T.
8363 A class requires a VTT if it has virtual bases.
8365 This holds
8366 1 - primary virtual pointer for complete object T
8367 2 - secondary VTTs for each direct non-virtual base of T which requires a
8369 3 - secondary virtual pointers for each direct or indirect base of T which
8370 has virtual bases or is reachable via a virtual path from T.
8371 4 - secondary VTTs for each direct or indirect virtual base of T.
8373 Secondary VTTs look like complete object VTTs without part 4. */
8375 static void
8376 build_vtt (tree t)
8378 tree type;
8379 tree vtt;
8380 tree index;
8381 vec<constructor_elt, va_gc> *inits;
8383 /* Build up the initializers for the VTT. */
8384 inits = NULL;
8385 index = size_zero_node;
8386 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
8388 /* If we didn't need a VTT, we're done. */
8389 if (!inits)
8390 return;
8392 /* Figure out the type of the VTT. */
8393 type = build_array_of_n_type (const_ptr_type_node,
8394 inits->length ());
8396 /* Now, build the VTT object itself. */
8397 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
8398 initialize_artificial_var (vtt, inits);
8399 /* Add the VTT to the vtables list. */
8400 DECL_CHAIN (vtt) = DECL_CHAIN (CLASSTYPE_VTABLES (t));
8401 DECL_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
8403 dump_vtt (t, vtt);
8406 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
8407 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
8408 and CHAIN the vtable pointer for this binfo after construction is
8409 complete. VALUE can also be another BINFO, in which case we recurse. */
8411 static tree
8412 binfo_ctor_vtable (tree binfo)
8414 tree vt;
8416 while (1)
8418 vt = BINFO_VTABLE (binfo);
8419 if (TREE_CODE (vt) == TREE_LIST)
8420 vt = TREE_VALUE (vt);
8421 if (TREE_CODE (vt) == TREE_BINFO)
8422 binfo = vt;
8423 else
8424 break;
8427 return vt;
8430 /* Data for secondary VTT initialization. */
8431 typedef struct secondary_vptr_vtt_init_data_s
8433 /* Is this the primary VTT? */
8434 bool top_level_p;
8436 /* Current index into the VTT. */
8437 tree index;
8439 /* Vector of initializers built up. */
8440 vec<constructor_elt, va_gc> *inits;
8442 /* The type being constructed by this secondary VTT. */
8443 tree type_being_constructed;
8444 } secondary_vptr_vtt_init_data;
8446 /* Recursively build the VTT-initializer for BINFO (which is in the
8447 hierarchy dominated by T). INITS points to the end of the initializer
8448 list to date. INDEX is the VTT index where the next element will be
8449 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
8450 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
8451 for virtual bases of T. When it is not so, we build the constructor
8452 vtables for the BINFO-in-T variant. */
8454 static void
8455 build_vtt_inits (tree binfo, tree t, vec<constructor_elt, va_gc> **inits,
8456 tree *index)
8458 int i;
8459 tree b;
8460 tree init;
8461 secondary_vptr_vtt_init_data data;
8462 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
8464 /* We only need VTTs for subobjects with virtual bases. */
8465 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
8466 return;
8468 /* We need to use a construction vtable if this is not the primary
8469 VTT. */
8470 if (!top_level_p)
8472 build_ctor_vtbl_group (binfo, t);
8474 /* Record the offset in the VTT where this sub-VTT can be found. */
8475 BINFO_SUBVTT_INDEX (binfo) = *index;
8478 /* Add the address of the primary vtable for the complete object. */
8479 init = binfo_ctor_vtable (binfo);
8480 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8481 if (top_level_p)
8483 gcc_assert (!BINFO_VPTR_INDEX (binfo));
8484 BINFO_VPTR_INDEX (binfo) = *index;
8486 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
8488 /* Recursively add the secondary VTTs for non-virtual bases. */
8489 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
8490 if (!BINFO_VIRTUAL_P (b))
8491 build_vtt_inits (b, t, inits, index);
8493 /* Add secondary virtual pointers for all subobjects of BINFO with
8494 either virtual bases or reachable along a virtual path, except
8495 subobjects that are non-virtual primary bases. */
8496 data.top_level_p = top_level_p;
8497 data.index = *index;
8498 data.inits = *inits;
8499 data.type_being_constructed = BINFO_TYPE (binfo);
8501 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
8503 *index = data.index;
8505 /* data.inits might have grown as we added secondary virtual pointers.
8506 Make sure our caller knows about the new vector. */
8507 *inits = data.inits;
8509 if (top_level_p)
8510 /* Add the secondary VTTs for virtual bases in inheritance graph
8511 order. */
8512 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
8514 if (!BINFO_VIRTUAL_P (b))
8515 continue;
8517 build_vtt_inits (b, t, inits, index);
8519 else
8520 /* Remove the ctor vtables we created. */
8521 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
8524 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
8525 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
8527 static tree
8528 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
8530 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
8532 /* We don't care about bases that don't have vtables. */
8533 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
8534 return dfs_skip_bases;
8536 /* We're only interested in proper subobjects of the type being
8537 constructed. */
8538 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
8539 return NULL_TREE;
8541 /* We're only interested in bases with virtual bases or reachable
8542 via a virtual path from the type being constructed. */
8543 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
8544 || binfo_via_virtual (binfo, data->type_being_constructed)))
8545 return dfs_skip_bases;
8547 /* We're not interested in non-virtual primary bases. */
8548 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
8549 return NULL_TREE;
8551 /* Record the index where this secondary vptr can be found. */
8552 if (data->top_level_p)
8554 gcc_assert (!BINFO_VPTR_INDEX (binfo));
8555 BINFO_VPTR_INDEX (binfo) = data->index;
8557 if (BINFO_VIRTUAL_P (binfo))
8559 /* It's a primary virtual base, and this is not a
8560 construction vtable. Find the base this is primary of in
8561 the inheritance graph, and use that base's vtable
8562 now. */
8563 while (BINFO_PRIMARY_P (binfo))
8564 binfo = BINFO_INHERITANCE_CHAIN (binfo);
8568 /* Add the initializer for the secondary vptr itself. */
8569 CONSTRUCTOR_APPEND_ELT (data->inits, NULL_TREE, binfo_ctor_vtable (binfo));
8571 /* Advance the vtt index. */
8572 data->index = size_binop (PLUS_EXPR, data->index,
8573 TYPE_SIZE_UNIT (ptr_type_node));
8575 return NULL_TREE;
8578 /* Called from build_vtt_inits via dfs_walk. After building
8579 constructor vtables and generating the sub-vtt from them, we need
8580 to restore the BINFO_VTABLES that were scribbled on. DATA is the
8581 binfo of the base whose sub vtt was generated. */
8583 static tree
8584 dfs_fixup_binfo_vtbls (tree binfo, void* data)
8586 tree vtable = BINFO_VTABLE (binfo);
8588 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
8589 /* If this class has no vtable, none of its bases do. */
8590 return dfs_skip_bases;
8592 if (!vtable)
8593 /* This might be a primary base, so have no vtable in this
8594 hierarchy. */
8595 return NULL_TREE;
8597 /* If we scribbled the construction vtable vptr into BINFO, clear it
8598 out now. */
8599 if (TREE_CODE (vtable) == TREE_LIST
8600 && (TREE_PURPOSE (vtable) == (tree) data))
8601 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
8603 return NULL_TREE;
8606 /* Build the construction vtable group for BINFO which is in the
8607 hierarchy dominated by T. */
8609 static void
8610 build_ctor_vtbl_group (tree binfo, tree t)
8612 tree type;
8613 tree vtbl;
8614 tree id;
8615 tree vbase;
8616 vec<constructor_elt, va_gc> *v;
8618 /* See if we've already created this construction vtable group. */
8619 id = mangle_ctor_vtbl_for_type (t, binfo);
8620 if (IDENTIFIER_GLOBAL_VALUE (id))
8621 return;
8623 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
8624 /* Build a version of VTBL (with the wrong type) for use in
8625 constructing the addresses of secondary vtables in the
8626 construction vtable group. */
8627 vtbl = build_vtable (t, id, ptr_type_node);
8628 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
8629 /* Don't export construction vtables from shared libraries. Even on
8630 targets that don't support hidden visibility, this tells
8631 can_refer_decl_in_current_unit_p not to assume that it's safe to
8632 access from a different compilation unit (bz 54314). */
8633 DECL_VISIBILITY (vtbl) = VISIBILITY_HIDDEN;
8634 DECL_VISIBILITY_SPECIFIED (vtbl) = true;
8636 v = NULL;
8637 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
8638 binfo, vtbl, t, &v);
8640 /* Add the vtables for each of our virtual bases using the vbase in T
8641 binfo. */
8642 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
8643 vbase;
8644 vbase = TREE_CHAIN (vbase))
8646 tree b;
8648 if (!BINFO_VIRTUAL_P (vbase))
8649 continue;
8650 b = copied_binfo (vbase, binfo);
8652 accumulate_vtbl_inits (b, vbase, binfo, vtbl, t, &v);
8655 /* Figure out the type of the construction vtable. */
8656 type = build_array_of_n_type (vtable_entry_type, v->length ());
8657 layout_type (type);
8658 TREE_TYPE (vtbl) = type;
8659 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
8660 layout_decl (vtbl, 0);
8662 /* Initialize the construction vtable. */
8663 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
8664 initialize_artificial_var (vtbl, v);
8665 dump_vtable (t, binfo, vtbl);
8668 /* Add the vtbl initializers for BINFO (and its bases other than
8669 non-virtual primaries) to the list of INITS. BINFO is in the
8670 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
8671 the constructor the vtbl inits should be accumulated for. (If this
8672 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
8673 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
8674 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
8675 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
8676 but are not necessarily the same in terms of layout. */
8678 static void
8679 accumulate_vtbl_inits (tree binfo,
8680 tree orig_binfo,
8681 tree rtti_binfo,
8682 tree vtbl,
8683 tree t,
8684 vec<constructor_elt, va_gc> **inits)
8686 int i;
8687 tree base_binfo;
8688 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8690 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
8692 /* If it doesn't have a vptr, we don't do anything. */
8693 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
8694 return;
8696 /* If we're building a construction vtable, we're not interested in
8697 subobjects that don't require construction vtables. */
8698 if (ctor_vtbl_p
8699 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
8700 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
8701 return;
8703 /* Build the initializers for the BINFO-in-T vtable. */
8704 dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, vtbl, t, inits);
8706 /* Walk the BINFO and its bases. We walk in preorder so that as we
8707 initialize each vtable we can figure out at what offset the
8708 secondary vtable lies from the primary vtable. We can't use
8709 dfs_walk here because we need to iterate through bases of BINFO
8710 and RTTI_BINFO simultaneously. */
8711 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8713 /* Skip virtual bases. */
8714 if (BINFO_VIRTUAL_P (base_binfo))
8715 continue;
8716 accumulate_vtbl_inits (base_binfo,
8717 BINFO_BASE_BINFO (orig_binfo, i),
8718 rtti_binfo, vtbl, t,
8719 inits);
8723 /* Called from accumulate_vtbl_inits. Adds the initializers for the
8724 BINFO vtable to L. */
8726 static void
8727 dfs_accumulate_vtbl_inits (tree binfo,
8728 tree orig_binfo,
8729 tree rtti_binfo,
8730 tree orig_vtbl,
8731 tree t,
8732 vec<constructor_elt, va_gc> **l)
8734 tree vtbl = NULL_TREE;
8735 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8736 int n_inits;
8738 if (ctor_vtbl_p
8739 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
8741 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
8742 primary virtual base. If it is not the same primary in
8743 the hierarchy of T, we'll need to generate a ctor vtable
8744 for it, to place at its location in T. If it is the same
8745 primary, we still need a VTT entry for the vtable, but it
8746 should point to the ctor vtable for the base it is a
8747 primary for within the sub-hierarchy of RTTI_BINFO.
8749 There are three possible cases:
8751 1) We are in the same place.
8752 2) We are a primary base within a lost primary virtual base of
8753 RTTI_BINFO.
8754 3) We are primary to something not a base of RTTI_BINFO. */
8756 tree b;
8757 tree last = NULL_TREE;
8759 /* First, look through the bases we are primary to for RTTI_BINFO
8760 or a virtual base. */
8761 b = binfo;
8762 while (BINFO_PRIMARY_P (b))
8764 b = BINFO_INHERITANCE_CHAIN (b);
8765 last = b;
8766 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
8767 goto found;
8769 /* If we run out of primary links, keep looking down our
8770 inheritance chain; we might be an indirect primary. */
8771 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
8772 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
8773 break;
8774 found:
8776 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
8777 base B and it is a base of RTTI_BINFO, this is case 2. In
8778 either case, we share our vtable with LAST, i.e. the
8779 derived-most base within B of which we are a primary. */
8780 if (b == rtti_binfo
8781 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
8782 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
8783 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
8784 binfo_ctor_vtable after everything's been set up. */
8785 vtbl = last;
8787 /* Otherwise, this is case 3 and we get our own. */
8789 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
8790 return;
8792 n_inits = vec_safe_length (*l);
8794 if (!vtbl)
8796 tree index;
8797 int non_fn_entries;
8799 /* Add the initializer for this vtable. */
8800 build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
8801 &non_fn_entries, l);
8803 /* Figure out the position to which the VPTR should point. */
8804 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, orig_vtbl);
8805 index = size_binop (MULT_EXPR,
8806 TYPE_SIZE_UNIT (vtable_entry_type),
8807 size_int (non_fn_entries + n_inits));
8808 vtbl = fold_build_pointer_plus (vtbl, index);
8811 if (ctor_vtbl_p)
8812 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
8813 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
8814 straighten this out. */
8815 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
8816 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
8817 /* Throw away any unneeded intializers. */
8818 (*l)->truncate (n_inits);
8819 else
8820 /* For an ordinary vtable, set BINFO_VTABLE. */
8821 BINFO_VTABLE (binfo) = vtbl;
8824 static GTY(()) tree abort_fndecl_addr;
8826 /* Construct the initializer for BINFO's virtual function table. BINFO
8827 is part of the hierarchy dominated by T. If we're building a
8828 construction vtable, the ORIG_BINFO is the binfo we should use to
8829 find the actual function pointers to put in the vtable - but they
8830 can be overridden on the path to most-derived in the graph that
8831 ORIG_BINFO belongs. Otherwise,
8832 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
8833 BINFO that should be indicated by the RTTI information in the
8834 vtable; it will be a base class of T, rather than T itself, if we
8835 are building a construction vtable.
8837 The value returned is a TREE_LIST suitable for wrapping in a
8838 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
8839 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
8840 number of non-function entries in the vtable.
8842 It might seem that this function should never be called with a
8843 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
8844 base is always subsumed by a derived class vtable. However, when
8845 we are building construction vtables, we do build vtables for
8846 primary bases; we need these while the primary base is being
8847 constructed. */
8849 static void
8850 build_vtbl_initializer (tree binfo,
8851 tree orig_binfo,
8852 tree t,
8853 tree rtti_binfo,
8854 int* non_fn_entries_p,
8855 vec<constructor_elt, va_gc> **inits)
8857 tree v;
8858 vtbl_init_data vid;
8859 unsigned ix, jx;
8860 tree vbinfo;
8861 vec<tree, va_gc> *vbases;
8862 constructor_elt *e;
8864 /* Initialize VID. */
8865 memset (&vid, 0, sizeof (vid));
8866 vid.binfo = binfo;
8867 vid.derived = t;
8868 vid.rtti_binfo = rtti_binfo;
8869 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
8870 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8871 vid.generate_vcall_entries = true;
8872 /* The first vbase or vcall offset is at index -3 in the vtable. */
8873 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
8875 /* Add entries to the vtable for RTTI. */
8876 build_rtti_vtbl_entries (binfo, &vid);
8878 /* Create an array for keeping track of the functions we've
8879 processed. When we see multiple functions with the same
8880 signature, we share the vcall offsets. */
8881 vec_alloc (vid.fns, 32);
8882 /* Add the vcall and vbase offset entries. */
8883 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
8885 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
8886 build_vbase_offset_vtbl_entries. */
8887 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
8888 vec_safe_iterate (vbases, ix, &vbinfo); ix++)
8889 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
8891 /* If the target requires padding between data entries, add that now. */
8892 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
8894 int n_entries = vec_safe_length (vid.inits);
8896 vec_safe_grow (vid.inits, TARGET_VTABLE_DATA_ENTRY_DISTANCE * n_entries);
8898 /* Move data entries into their new positions and add padding
8899 after the new positions. Iterate backwards so we don't
8900 overwrite entries that we would need to process later. */
8901 for (ix = n_entries - 1;
8902 vid.inits->iterate (ix, &e);
8903 ix--)
8905 int j;
8906 int new_position = (TARGET_VTABLE_DATA_ENTRY_DISTANCE * ix
8907 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE - 1));
8909 (*vid.inits)[new_position] = *e;
8911 for (j = 1; j < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++j)
8913 constructor_elt *f = &(*vid.inits)[new_position - j];
8914 f->index = NULL_TREE;
8915 f->value = build1 (NOP_EXPR, vtable_entry_type,
8916 null_pointer_node);
8921 if (non_fn_entries_p)
8922 *non_fn_entries_p = vec_safe_length (vid.inits);
8924 /* The initializers for virtual functions were built up in reverse
8925 order. Straighten them out and add them to the running list in one
8926 step. */
8927 jx = vec_safe_length (*inits);
8928 vec_safe_grow (*inits, jx + vid.inits->length ());
8930 for (ix = vid.inits->length () - 1;
8931 vid.inits->iterate (ix, &e);
8932 ix--, jx++)
8933 (**inits)[jx] = *e;
8935 /* Go through all the ordinary virtual functions, building up
8936 initializers. */
8937 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
8939 tree delta;
8940 tree vcall_index;
8941 tree fn, fn_original;
8942 tree init = NULL_TREE;
8944 fn = BV_FN (v);
8945 fn_original = fn;
8946 if (DECL_THUNK_P (fn))
8948 if (!DECL_NAME (fn))
8949 finish_thunk (fn);
8950 if (THUNK_ALIAS (fn))
8952 fn = THUNK_ALIAS (fn);
8953 BV_FN (v) = fn;
8955 fn_original = THUNK_TARGET (fn);
8958 /* If the only definition of this function signature along our
8959 primary base chain is from a lost primary, this vtable slot will
8960 never be used, so just zero it out. This is important to avoid
8961 requiring extra thunks which cannot be generated with the function.
8963 We first check this in update_vtable_entry_for_fn, so we handle
8964 restored primary bases properly; we also need to do it here so we
8965 zero out unused slots in ctor vtables, rather than filling them
8966 with erroneous values (though harmless, apart from relocation
8967 costs). */
8968 if (BV_LOST_PRIMARY (v))
8969 init = size_zero_node;
8971 if (! init)
8973 /* Pull the offset for `this', and the function to call, out of
8974 the list. */
8975 delta = BV_DELTA (v);
8976 vcall_index = BV_VCALL_INDEX (v);
8978 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
8979 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
8981 /* You can't call an abstract virtual function; it's abstract.
8982 So, we replace these functions with __pure_virtual. */
8983 if (DECL_PURE_VIRTUAL_P (fn_original))
8985 fn = abort_fndecl;
8986 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8988 if (abort_fndecl_addr == NULL)
8989 abort_fndecl_addr
8990 = fold_convert (vfunc_ptr_type_node,
8991 build_fold_addr_expr (fn));
8992 init = abort_fndecl_addr;
8995 /* Likewise for deleted virtuals. */
8996 else if (DECL_DELETED_FN (fn_original))
8998 fn = get_identifier ("__cxa_deleted_virtual");
8999 if (!get_global_value_if_present (fn, &fn))
9000 fn = push_library_fn (fn, (build_function_type_list
9001 (void_type_node, NULL_TREE)),
9002 NULL_TREE, ECF_NORETURN);
9003 if (!TARGET_VTABLE_USES_DESCRIPTORS)
9004 init = fold_convert (vfunc_ptr_type_node,
9005 build_fold_addr_expr (fn));
9007 else
9009 if (!integer_zerop (delta) || vcall_index)
9011 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
9012 if (!DECL_NAME (fn))
9013 finish_thunk (fn);
9015 /* Take the address of the function, considering it to be of an
9016 appropriate generic type. */
9017 if (!TARGET_VTABLE_USES_DESCRIPTORS)
9018 init = fold_convert (vfunc_ptr_type_node,
9019 build_fold_addr_expr (fn));
9020 /* Don't refer to a virtual destructor from a constructor
9021 vtable or a vtable for an abstract class, since destroying
9022 an object under construction is undefined behavior and we
9023 don't want it to be considered a candidate for speculative
9024 devirtualization. But do create the thunk for ABI
9025 compliance. */
9026 if (DECL_DESTRUCTOR_P (fn_original)
9027 && (CLASSTYPE_PURE_VIRTUALS (DECL_CONTEXT (fn_original))
9028 || orig_binfo != binfo))
9029 init = size_zero_node;
9033 /* And add it to the chain of initializers. */
9034 if (TARGET_VTABLE_USES_DESCRIPTORS)
9036 int i;
9037 if (init == size_zero_node)
9038 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
9039 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
9040 else
9041 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
9043 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
9044 fn, build_int_cst (NULL_TREE, i));
9045 TREE_CONSTANT (fdesc) = 1;
9047 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, fdesc);
9050 else
9051 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
9055 /* Adds to vid->inits the initializers for the vbase and vcall
9056 offsets in BINFO, which is in the hierarchy dominated by T. */
9058 static void
9059 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
9061 tree b;
9063 /* If this is a derived class, we must first create entries
9064 corresponding to the primary base class. */
9065 b = get_primary_binfo (binfo);
9066 if (b)
9067 build_vcall_and_vbase_vtbl_entries (b, vid);
9069 /* Add the vbase entries for this base. */
9070 build_vbase_offset_vtbl_entries (binfo, vid);
9071 /* Add the vcall entries for this base. */
9072 build_vcall_offset_vtbl_entries (binfo, vid);
9075 /* Returns the initializers for the vbase offset entries in the vtable
9076 for BINFO (which is part of the class hierarchy dominated by T), in
9077 reverse order. VBASE_OFFSET_INDEX gives the vtable index
9078 where the next vbase offset will go. */
9080 static void
9081 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
9083 tree vbase;
9084 tree t;
9085 tree non_primary_binfo;
9087 /* If there are no virtual baseclasses, then there is nothing to
9088 do. */
9089 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
9090 return;
9092 t = vid->derived;
9094 /* We might be a primary base class. Go up the inheritance hierarchy
9095 until we find the most derived class of which we are a primary base:
9096 it is the offset of that which we need to use. */
9097 non_primary_binfo = binfo;
9098 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
9100 tree b;
9102 /* If we have reached a virtual base, then it must be a primary
9103 base (possibly multi-level) of vid->binfo, or we wouldn't
9104 have called build_vcall_and_vbase_vtbl_entries for it. But it
9105 might be a lost primary, so just skip down to vid->binfo. */
9106 if (BINFO_VIRTUAL_P (non_primary_binfo))
9108 non_primary_binfo = vid->binfo;
9109 break;
9112 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
9113 if (get_primary_binfo (b) != non_primary_binfo)
9114 break;
9115 non_primary_binfo = b;
9118 /* Go through the virtual bases, adding the offsets. */
9119 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
9120 vbase;
9121 vbase = TREE_CHAIN (vbase))
9123 tree b;
9124 tree delta;
9126 if (!BINFO_VIRTUAL_P (vbase))
9127 continue;
9129 /* Find the instance of this virtual base in the complete
9130 object. */
9131 b = copied_binfo (vbase, binfo);
9133 /* If we've already got an offset for this virtual base, we
9134 don't need another one. */
9135 if (BINFO_VTABLE_PATH_MARKED (b))
9136 continue;
9137 BINFO_VTABLE_PATH_MARKED (b) = 1;
9139 /* Figure out where we can find this vbase offset. */
9140 delta = size_binop (MULT_EXPR,
9141 vid->index,
9142 convert (ssizetype,
9143 TYPE_SIZE_UNIT (vtable_entry_type)));
9144 if (vid->primary_vtbl_p)
9145 BINFO_VPTR_FIELD (b) = delta;
9147 if (binfo != TYPE_BINFO (t))
9148 /* The vbase offset had better be the same. */
9149 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
9151 /* The next vbase will come at a more negative offset. */
9152 vid->index = size_binop (MINUS_EXPR, vid->index,
9153 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
9155 /* The initializer is the delta from BINFO to this virtual base.
9156 The vbase offsets go in reverse inheritance-graph order, and
9157 we are walking in inheritance graph order so these end up in
9158 the right order. */
9159 delta = size_diffop_loc (input_location,
9160 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
9162 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE,
9163 fold_build1_loc (input_location, NOP_EXPR,
9164 vtable_entry_type, delta));
9168 /* Adds the initializers for the vcall offset entries in the vtable
9169 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
9170 to VID->INITS. */
9172 static void
9173 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
9175 /* We only need these entries if this base is a virtual base. We
9176 compute the indices -- but do not add to the vtable -- when
9177 building the main vtable for a class. */
9178 if (binfo == TYPE_BINFO (vid->derived)
9179 || (BINFO_VIRTUAL_P (binfo)
9180 /* If BINFO is RTTI_BINFO, then (since BINFO does not
9181 correspond to VID->DERIVED), we are building a primary
9182 construction virtual table. Since this is a primary
9183 virtual table, we do not need the vcall offsets for
9184 BINFO. */
9185 && binfo != vid->rtti_binfo))
9187 /* We need a vcall offset for each of the virtual functions in this
9188 vtable. For example:
9190 class A { virtual void f (); };
9191 class B1 : virtual public A { virtual void f (); };
9192 class B2 : virtual public A { virtual void f (); };
9193 class C: public B1, public B2 { virtual void f (); };
9195 A C object has a primary base of B1, which has a primary base of A. A
9196 C also has a secondary base of B2, which no longer has a primary base
9197 of A. So the B2-in-C construction vtable needs a secondary vtable for
9198 A, which will adjust the A* to a B2* to call f. We have no way of
9199 knowing what (or even whether) this offset will be when we define B2,
9200 so we store this "vcall offset" in the A sub-vtable and look it up in
9201 a "virtual thunk" for B2::f.
9203 We need entries for all the functions in our primary vtable and
9204 in our non-virtual bases' secondary vtables. */
9205 vid->vbase = binfo;
9206 /* If we are just computing the vcall indices -- but do not need
9207 the actual entries -- not that. */
9208 if (!BINFO_VIRTUAL_P (binfo))
9209 vid->generate_vcall_entries = false;
9210 /* Now, walk through the non-virtual bases, adding vcall offsets. */
9211 add_vcall_offset_vtbl_entries_r (binfo, vid);
9215 /* Build vcall offsets, starting with those for BINFO. */
9217 static void
9218 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
9220 int i;
9221 tree primary_binfo;
9222 tree base_binfo;
9224 /* Don't walk into virtual bases -- except, of course, for the
9225 virtual base for which we are building vcall offsets. Any
9226 primary virtual base will have already had its offsets generated
9227 through the recursion in build_vcall_and_vbase_vtbl_entries. */
9228 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
9229 return;
9231 /* If BINFO has a primary base, process it first. */
9232 primary_binfo = get_primary_binfo (binfo);
9233 if (primary_binfo)
9234 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
9236 /* Add BINFO itself to the list. */
9237 add_vcall_offset_vtbl_entries_1 (binfo, vid);
9239 /* Scan the non-primary bases of BINFO. */
9240 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
9241 if (base_binfo != primary_binfo)
9242 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
9245 /* Called from build_vcall_offset_vtbl_entries_r. */
9247 static void
9248 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
9250 /* Make entries for the rest of the virtuals. */
9251 if (abi_version_at_least (2))
9253 tree orig_fn;
9255 /* The ABI requires that the methods be processed in declaration
9256 order. G++ 3.2 used the order in the vtable. */
9257 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
9258 orig_fn;
9259 orig_fn = DECL_CHAIN (orig_fn))
9260 if (DECL_VINDEX (orig_fn))
9261 add_vcall_offset (orig_fn, binfo, vid);
9263 else
9265 tree derived_virtuals;
9266 tree base_virtuals;
9267 tree orig_virtuals;
9268 /* If BINFO is a primary base, the most derived class which has
9269 BINFO as a primary base; otherwise, just BINFO. */
9270 tree non_primary_binfo;
9272 /* We might be a primary base class. Go up the inheritance hierarchy
9273 until we find the most derived class of which we are a primary base:
9274 it is the BINFO_VIRTUALS there that we need to consider. */
9275 non_primary_binfo = binfo;
9276 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
9278 tree b;
9280 /* If we have reached a virtual base, then it must be vid->vbase,
9281 because we ignore other virtual bases in
9282 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
9283 base (possibly multi-level) of vid->binfo, or we wouldn't
9284 have called build_vcall_and_vbase_vtbl_entries for it. But it
9285 might be a lost primary, so just skip down to vid->binfo. */
9286 if (BINFO_VIRTUAL_P (non_primary_binfo))
9288 gcc_assert (non_primary_binfo == vid->vbase);
9289 non_primary_binfo = vid->binfo;
9290 break;
9293 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
9294 if (get_primary_binfo (b) != non_primary_binfo)
9295 break;
9296 non_primary_binfo = b;
9299 if (vid->ctor_vtbl_p)
9300 /* For a ctor vtable we need the equivalent binfo within the hierarchy
9301 where rtti_binfo is the most derived type. */
9302 non_primary_binfo
9303 = original_binfo (non_primary_binfo, vid->rtti_binfo);
9305 for (base_virtuals = BINFO_VIRTUALS (binfo),
9306 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
9307 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
9308 base_virtuals;
9309 base_virtuals = TREE_CHAIN (base_virtuals),
9310 derived_virtuals = TREE_CHAIN (derived_virtuals),
9311 orig_virtuals = TREE_CHAIN (orig_virtuals))
9313 tree orig_fn;
9315 /* Find the declaration that originally caused this function to
9316 be present in BINFO_TYPE (binfo). */
9317 orig_fn = BV_FN (orig_virtuals);
9319 /* When processing BINFO, we only want to generate vcall slots for
9320 function slots introduced in BINFO. So don't try to generate
9321 one if the function isn't even defined in BINFO. */
9322 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
9323 continue;
9325 add_vcall_offset (orig_fn, binfo, vid);
9330 /* Add a vcall offset entry for ORIG_FN to the vtable. */
9332 static void
9333 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
9335 size_t i;
9336 tree vcall_offset;
9337 tree derived_entry;
9339 /* If there is already an entry for a function with the same
9340 signature as FN, then we do not need a second vcall offset.
9341 Check the list of functions already present in the derived
9342 class vtable. */
9343 FOR_EACH_VEC_SAFE_ELT (vid->fns, i, derived_entry)
9345 if (same_signature_p (derived_entry, orig_fn)
9346 /* We only use one vcall offset for virtual destructors,
9347 even though there are two virtual table entries. */
9348 || (DECL_DESTRUCTOR_P (derived_entry)
9349 && DECL_DESTRUCTOR_P (orig_fn)))
9350 return;
9353 /* If we are building these vcall offsets as part of building
9354 the vtable for the most derived class, remember the vcall
9355 offset. */
9356 if (vid->binfo == TYPE_BINFO (vid->derived))
9358 tree_pair_s elt = {orig_fn, vid->index};
9359 vec_safe_push (CLASSTYPE_VCALL_INDICES (vid->derived), elt);
9362 /* The next vcall offset will be found at a more negative
9363 offset. */
9364 vid->index = size_binop (MINUS_EXPR, vid->index,
9365 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
9367 /* Keep track of this function. */
9368 vec_safe_push (vid->fns, orig_fn);
9370 if (vid->generate_vcall_entries)
9372 tree base;
9373 tree fn;
9375 /* Find the overriding function. */
9376 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
9377 if (fn == error_mark_node)
9378 vcall_offset = build_zero_cst (vtable_entry_type);
9379 else
9381 base = TREE_VALUE (fn);
9383 /* The vbase we're working on is a primary base of
9384 vid->binfo. But it might be a lost primary, so its
9385 BINFO_OFFSET might be wrong, so we just use the
9386 BINFO_OFFSET from vid->binfo. */
9387 vcall_offset = size_diffop_loc (input_location,
9388 BINFO_OFFSET (base),
9389 BINFO_OFFSET (vid->binfo));
9390 vcall_offset = fold_build1_loc (input_location,
9391 NOP_EXPR, vtable_entry_type,
9392 vcall_offset);
9394 /* Add the initializer to the vtable. */
9395 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, vcall_offset);
9399 /* Return vtbl initializers for the RTTI entries corresponding to the
9400 BINFO's vtable. The RTTI entries should indicate the object given
9401 by VID->rtti_binfo. */
9403 static void
9404 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
9406 tree b;
9407 tree t;
9408 tree offset;
9409 tree decl;
9410 tree init;
9412 t = BINFO_TYPE (vid->rtti_binfo);
9414 /* To find the complete object, we will first convert to our most
9415 primary base, and then add the offset in the vtbl to that value. */
9416 b = binfo;
9417 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
9418 && !BINFO_LOST_PRIMARY_P (b))
9420 tree primary_base;
9422 primary_base = get_primary_binfo (b);
9423 gcc_assert (BINFO_PRIMARY_P (primary_base)
9424 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
9425 b = primary_base;
9427 offset = size_diffop_loc (input_location,
9428 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
9430 /* The second entry is the address of the typeinfo object. */
9431 if (flag_rtti)
9432 decl = build_address (get_tinfo_decl (t));
9433 else
9434 decl = integer_zero_node;
9436 /* Convert the declaration to a type that can be stored in the
9437 vtable. */
9438 init = build_nop (vfunc_ptr_type_node, decl);
9439 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
9441 /* Add the offset-to-top entry. It comes earlier in the vtable than
9442 the typeinfo entry. Convert the offset to look like a
9443 function pointer, so that we can put it in the vtable. */
9444 init = build_nop (vfunc_ptr_type_node, offset);
9445 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
9448 /* TRUE iff TYPE is uniquely derived from PARENT. Ignores
9449 accessibility. */
9451 bool
9452 uniquely_derived_from_p (tree parent, tree type)
9454 tree base = lookup_base (type, parent, ba_unique, NULL, tf_none);
9455 return base && base != error_mark_node;
9458 /* TRUE iff TYPE is publicly & uniquely derived from PARENT. */
9460 bool
9461 publicly_uniquely_derived_p (tree parent, tree type)
9463 tree base = lookup_base (type, parent, ba_ignore_scope | ba_check,
9464 NULL, tf_none);
9465 return base && base != error_mark_node;
9468 /* CTX1 and CTX2 are declaration contexts. Return the innermost common
9469 class between them, if any. */
9471 tree
9472 common_enclosing_class (tree ctx1, tree ctx2)
9474 if (!TYPE_P (ctx1) || !TYPE_P (ctx2))
9475 return NULL_TREE;
9476 gcc_assert (ctx1 == TYPE_MAIN_VARIANT (ctx1)
9477 && ctx2 == TYPE_MAIN_VARIANT (ctx2));
9478 if (ctx1 == ctx2)
9479 return ctx1;
9480 for (tree t = ctx1; TYPE_P (t); t = TYPE_CONTEXT (t))
9481 TYPE_MARKED_P (t) = true;
9482 tree found = NULL_TREE;
9483 for (tree t = ctx2; TYPE_P (t); t = TYPE_CONTEXT (t))
9484 if (TYPE_MARKED_P (t))
9486 found = t;
9487 break;
9489 for (tree t = ctx1; TYPE_P (t); t = TYPE_CONTEXT (t))
9490 TYPE_MARKED_P (t) = false;
9491 return found;
9494 #include "gt-cp-class.h"