1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
38 #include "tree-dump.h"
39 #include "splay-tree.h"
41 /* The number of nested classes being processed. If we are not in the
42 scope of any class, this is zero. */
44 int current_class_depth;
46 /* In order to deal with nested classes, we keep a stack of classes.
47 The topmost entry is the innermost class, and is the entry at index
48 CURRENT_CLASS_DEPTH */
50 typedef struct class_stack_node {
51 /* The name of the class. */
54 /* The _TYPE node for the class. */
57 /* The access specifier pending for new declarations in the scope of
61 /* If were defining TYPE, the names used in this class. */
62 splay_tree names_used;
64 /* Nonzero if this class is no longer open, because of a call to
67 }* class_stack_node_t;
69 typedef struct vtbl_init_data_s
71 /* The base for which we're building initializers. */
73 /* The type of the most-derived type. */
75 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
76 unless ctor_vtbl_p is true. */
78 /* The negative-index vtable initializers built up so far. These
79 are in order from least negative index to most negative index. */
80 VEC(constructor_elt,gc) *inits;
81 /* The binfo for the virtual base for which we're building
82 vcall offset initializers. */
84 /* The functions in vbase for which we have already provided vcall
87 /* The vtable index of the next vcall or vbase offset. */
89 /* Nonzero if we are building the initializer for the primary
92 /* Nonzero if we are building the initializer for a construction
95 /* True when adding vcall offset entries to the vtable. False when
96 merely computing the indices. */
97 bool generate_vcall_entries;
100 /* The type of a function passed to walk_subobject_offsets. */
101 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
103 /* The stack itself. This is a dynamically resized array. The
104 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
105 static int current_class_stack_size;
106 static class_stack_node_t current_class_stack;
108 /* The size of the largest empty class seen in this translation unit. */
109 static GTY (()) tree sizeof_biggest_empty_class;
111 /* An array of all local classes present in this translation unit, in
112 declaration order. */
113 VEC(tree,gc) *local_classes;
115 static tree get_vfield_name (tree);
116 static void finish_struct_anon (tree);
117 static tree get_vtable_name (tree);
118 static tree get_basefndecls (tree, tree);
119 static int build_primary_vtable (tree, tree);
120 static int build_secondary_vtable (tree);
121 static void finish_vtbls (tree);
122 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
123 static void finish_struct_bits (tree);
124 static int alter_access (tree, tree, tree);
125 static void handle_using_decl (tree, tree);
126 static tree dfs_modify_vtables (tree, void *);
127 static tree modify_all_vtables (tree, tree);
128 static void determine_primary_bases (tree);
129 static void finish_struct_methods (tree);
130 static void maybe_warn_about_overly_private_class (tree);
131 static int method_name_cmp (const void *, const void *);
132 static int resort_method_name_cmp (const void *, const void *);
133 static void add_implicitly_declared_members (tree, int, int);
134 static tree fixed_type_or_null (tree, int *, int *);
135 static tree build_simple_base_path (tree expr, tree binfo);
136 static tree build_vtbl_ref_1 (tree, tree);
137 static void build_vtbl_initializer (tree, tree, tree, tree, int *,
138 VEC(constructor_elt,gc) **);
139 static int count_fields (tree);
140 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
141 static bool check_bitfield_decl (tree);
142 static void check_field_decl (tree, tree, int *, int *, int *);
143 static void check_field_decls (tree, tree *, int *, int *);
144 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
145 static void build_base_fields (record_layout_info, splay_tree, tree *);
146 static void check_methods (tree);
147 static void remove_zero_width_bit_fields (tree);
148 static void check_bases (tree, int *, int *);
149 static void check_bases_and_members (tree);
150 static tree create_vtable_ptr (tree, tree *);
151 static void include_empty_classes (record_layout_info);
152 static void layout_class_type (tree, tree *);
153 static void propagate_binfo_offsets (tree, tree);
154 static void layout_virtual_bases (record_layout_info, splay_tree);
155 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
156 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
157 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
158 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
159 static void add_vcall_offset (tree, tree, vtbl_init_data *);
160 static void layout_vtable_decl (tree, int);
161 static tree dfs_find_final_overrider_pre (tree, void *);
162 static tree dfs_find_final_overrider_post (tree, void *);
163 static tree find_final_overrider (tree, tree, tree);
164 static int make_new_vtable (tree, tree);
165 static tree get_primary_binfo (tree);
166 static int maybe_indent_hierarchy (FILE *, int, int);
167 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
168 static void dump_class_hierarchy (tree);
169 static void dump_class_hierarchy_1 (FILE *, int, tree);
170 static void dump_array (FILE *, tree);
171 static void dump_vtable (tree, tree, tree);
172 static void dump_vtt (tree, tree);
173 static void dump_thunk (FILE *, int, tree);
174 static tree build_vtable (tree, tree, tree);
175 static void initialize_vtable (tree, VEC(constructor_elt,gc) *);
176 static void layout_nonempty_base_or_field (record_layout_info,
177 tree, tree, splay_tree);
178 static tree end_of_class (tree, int);
179 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
180 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree,
181 VEC(constructor_elt,gc) **);
182 static void dfs_accumulate_vtbl_inits (tree, tree, tree, tree, tree,
183 VEC(constructor_elt,gc) **);
184 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
185 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
186 static void clone_constructors_and_destructors (tree);
187 static tree build_clone (tree, tree);
188 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
189 static void build_ctor_vtbl_group (tree, tree);
190 static void build_vtt (tree);
191 static tree binfo_ctor_vtable (tree);
192 static void build_vtt_inits (tree, tree, VEC(constructor_elt,gc) **, tree *);
193 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
194 static tree dfs_fixup_binfo_vtbls (tree, void *);
195 static int record_subobject_offset (tree, tree, splay_tree);
196 static int check_subobject_offset (tree, tree, splay_tree);
197 static int walk_subobject_offsets (tree, subobject_offset_fn,
198 tree, splay_tree, tree, int);
199 static void record_subobject_offsets (tree, tree, splay_tree, bool);
200 static int layout_conflict_p (tree, tree, splay_tree, int);
201 static int splay_tree_compare_integer_csts (splay_tree_key k1,
203 static void warn_about_ambiguous_bases (tree);
204 static bool type_requires_array_cookie (tree);
205 static bool contains_empty_class_p (tree);
206 static bool base_derived_from (tree, tree);
207 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
208 static tree end_of_base (tree);
209 static tree get_vcall_index (tree, tree);
211 /* Variables shared between class.c and call.c. */
213 #ifdef GATHER_STATISTICS
215 int n_vtable_entries = 0;
216 int n_vtable_searches = 0;
217 int n_vtable_elems = 0;
218 int n_convert_harshness = 0;
219 int n_compute_conversion_costs = 0;
220 int n_inner_fields_searched = 0;
223 /* Convert to or from a base subobject. EXPR is an expression of type
224 `A' or `A*', an expression of type `B' or `B*' is returned. To
225 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
226 the B base instance within A. To convert base A to derived B, CODE
227 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
228 In this latter case, A must not be a morally virtual base of B.
229 NONNULL is true if EXPR is known to be non-NULL (this is only
230 needed when EXPR is of pointer type). CV qualifiers are preserved
234 build_base_path (enum tree_code code,
239 tree v_binfo = NULL_TREE;
240 tree d_binfo = NULL_TREE;
244 tree null_test = NULL;
245 tree ptr_target_type;
247 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
248 bool has_empty = false;
251 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
252 return error_mark_node;
254 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
257 if (is_empty_class (BINFO_TYPE (probe)))
259 if (!v_binfo && BINFO_VIRTUAL_P (probe))
263 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
265 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
267 gcc_assert ((code == MINUS_EXPR
268 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
269 || (code == PLUS_EXPR
270 && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
272 if (binfo == d_binfo)
276 if (code == MINUS_EXPR && v_binfo)
278 error ("cannot convert from base %qT to derived type %qT via virtual base %qT",
279 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
280 return error_mark_node;
284 /* This must happen before the call to save_expr. */
285 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
287 expr = mark_rvalue_use (expr);
289 offset = BINFO_OFFSET (binfo);
290 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
291 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
293 /* Do we need to look in the vtable for the real offset? */
294 virtual_access = (v_binfo && fixed_type_p <= 0);
296 /* Don't bother with the calculations inside sizeof; they'll ICE if the
297 source type is incomplete and the pointer value doesn't matter. */
298 if (cp_unevaluated_operand != 0)
300 expr = build_nop (build_pointer_type (target_type), expr);
302 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
306 /* Do we need to check for a null pointer? */
307 if (want_pointer && !nonnull)
309 /* If we know the conversion will not actually change the value
310 of EXPR, then we can avoid testing the expression for NULL.
311 We have to avoid generating a COMPONENT_REF for a base class
312 field, because other parts of the compiler know that such
313 expressions are always non-NULL. */
314 if (!virtual_access && integer_zerop (offset))
317 /* TARGET_TYPE has been extracted from BINFO, and, is
318 therefore always cv-unqualified. Extract the
319 cv-qualifiers from EXPR so that the expression returned
320 matches the input. */
321 class_type = TREE_TYPE (TREE_TYPE (expr));
323 = cp_build_qualified_type (target_type,
324 cp_type_quals (class_type));
325 return build_nop (build_pointer_type (target_type), expr);
327 null_test = error_mark_node;
330 /* Protect against multiple evaluation if necessary. */
331 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
332 expr = save_expr (expr);
334 /* Now that we've saved expr, build the real null test. */
337 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
338 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
342 /* If this is a simple base reference, express it as a COMPONENT_REF. */
343 if (code == PLUS_EXPR && !virtual_access
344 /* We don't build base fields for empty bases, and they aren't very
345 interesting to the optimizers anyway. */
348 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
349 expr = build_simple_base_path (expr, binfo);
351 expr = build_address (expr);
352 target_type = TREE_TYPE (expr);
358 /* Going via virtual base V_BINFO. We need the static offset
359 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
360 V_BINFO. That offset is an entry in D_BINFO's vtable. */
363 if (fixed_type_p < 0 && in_base_initializer)
365 /* In a base member initializer, we cannot rely on the
366 vtable being set up. We have to indirect via the
370 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
371 t = build_pointer_type (t);
372 v_offset = convert (t, current_vtt_parm);
373 v_offset = cp_build_indirect_ref (v_offset, RO_NULL,
374 tf_warning_or_error);
377 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, RO_NULL,
378 tf_warning_or_error),
379 TREE_TYPE (TREE_TYPE (expr)));
381 v_offset = build2 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
382 v_offset, fold_convert (sizetype, BINFO_VPTR_FIELD (v_binfo)));
383 v_offset = build1 (NOP_EXPR,
384 build_pointer_type (ptrdiff_type_node),
386 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, tf_warning_or_error);
387 TREE_CONSTANT (v_offset) = 1;
389 offset = convert_to_integer (ptrdiff_type_node,
390 size_diffop_loc (input_location, offset,
391 BINFO_OFFSET (v_binfo)));
393 if (!integer_zerop (offset))
394 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
396 if (fixed_type_p < 0)
397 /* Negative fixed_type_p means this is a constructor or destructor;
398 virtual base layout is fixed in in-charge [cd]tors, but not in
400 offset = build3 (COND_EXPR, ptrdiff_type_node,
401 build2 (EQ_EXPR, boolean_type_node,
402 current_in_charge_parm, integer_zero_node),
404 convert_to_integer (ptrdiff_type_node,
405 BINFO_OFFSET (binfo)));
410 target_type = cp_build_qualified_type
411 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
412 ptr_target_type = build_pointer_type (target_type);
414 target_type = ptr_target_type;
416 expr = build1 (NOP_EXPR, ptr_target_type, expr);
418 if (!integer_zerop (offset))
420 offset = fold_convert (sizetype, offset);
421 if (code == MINUS_EXPR)
422 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
423 expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
429 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
433 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
434 fold_build1_loc (input_location, NOP_EXPR, target_type,
440 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
441 Perform a derived-to-base conversion by recursively building up a
442 sequence of COMPONENT_REFs to the appropriate base fields. */
445 build_simple_base_path (tree expr, tree binfo)
447 tree type = BINFO_TYPE (binfo);
448 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
451 if (d_binfo == NULL_TREE)
455 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
457 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
458 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
459 an lvalue in the front end; only _DECLs and _REFs are lvalues
461 temp = unary_complex_lvalue (ADDR_EXPR, expr);
463 expr = cp_build_indirect_ref (temp, RO_NULL, tf_warning_or_error);
469 expr = build_simple_base_path (expr, d_binfo);
471 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
472 field; field = TREE_CHAIN (field))
473 /* Is this the base field created by build_base_field? */
474 if (TREE_CODE (field) == FIELD_DECL
475 && DECL_FIELD_IS_BASE (field)
476 && TREE_TYPE (field) == type)
478 /* We don't use build_class_member_access_expr here, as that
479 has unnecessary checks, and more importantly results in
480 recursive calls to dfs_walk_once. */
481 int type_quals = cp_type_quals (TREE_TYPE (expr));
483 expr = build3 (COMPONENT_REF,
484 cp_build_qualified_type (type, type_quals),
485 expr, field, NULL_TREE);
486 expr = fold_if_not_in_template (expr);
488 /* Mark the expression const or volatile, as appropriate.
489 Even though we've dealt with the type above, we still have
490 to mark the expression itself. */
491 if (type_quals & TYPE_QUAL_CONST)
492 TREE_READONLY (expr) = 1;
493 if (type_quals & TYPE_QUAL_VOLATILE)
494 TREE_THIS_VOLATILE (expr) = 1;
499 /* Didn't find the base field?!? */
503 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
504 type is a class type or a pointer to a class type. In the former
505 case, TYPE is also a class type; in the latter it is another
506 pointer type. If CHECK_ACCESS is true, an error message is emitted
507 if TYPE is inaccessible. If OBJECT has pointer type, the value is
508 assumed to be non-NULL. */
511 convert_to_base (tree object, tree type, bool check_access, bool nonnull,
512 tsubst_flags_t complain)
518 if (TYPE_PTR_P (TREE_TYPE (object)))
520 object_type = TREE_TYPE (TREE_TYPE (object));
521 type = TREE_TYPE (type);
524 object_type = TREE_TYPE (object);
526 access = check_access ? ba_check : ba_unique;
527 if (!(complain & tf_error))
529 binfo = lookup_base (object_type, type,
532 if (!binfo || binfo == error_mark_node)
533 return error_mark_node;
535 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
538 /* EXPR is an expression with unqualified class type. BASE is a base
539 binfo of that class type. Returns EXPR, converted to the BASE
540 type. This function assumes that EXPR is the most derived class;
541 therefore virtual bases can be found at their static offsets. */
544 convert_to_base_statically (tree expr, tree base)
548 expr_type = TREE_TYPE (expr);
549 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
553 pointer_type = build_pointer_type (expr_type);
555 /* We use fold_build2 and fold_convert below to simplify the trees
556 provided to the optimizers. It is not safe to call these functions
557 when processing a template because they do not handle C++-specific
559 gcc_assert (!processing_template_decl);
560 expr = cp_build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1,
561 tf_warning_or_error);
562 if (!integer_zerop (BINFO_OFFSET (base)))
563 expr = fold_build2_loc (input_location,
564 POINTER_PLUS_EXPR, pointer_type, expr,
565 fold_convert (sizetype, BINFO_OFFSET (base)));
566 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
567 expr = build_fold_indirect_ref_loc (input_location, expr);
575 build_vfield_ref (tree datum, tree type)
577 tree vfield, vcontext;
579 if (datum == error_mark_node)
580 return error_mark_node;
582 /* First, convert to the requested type. */
583 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
584 datum = convert_to_base (datum, type, /*check_access=*/false,
585 /*nonnull=*/true, tf_warning_or_error);
587 /* Second, the requested type may not be the owner of its own vptr.
588 If not, convert to the base class that owns it. We cannot use
589 convert_to_base here, because VCONTEXT may appear more than once
590 in the inheritance hierarchy of TYPE, and thus direct conversion
591 between the types may be ambiguous. Following the path back up
592 one step at a time via primary bases avoids the problem. */
593 vfield = TYPE_VFIELD (type);
594 vcontext = DECL_CONTEXT (vfield);
595 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
597 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
598 type = TREE_TYPE (datum);
601 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
604 /* Given an object INSTANCE, return an expression which yields the
605 vtable element corresponding to INDEX. There are many special
606 cases for INSTANCE which we take care of here, mainly to avoid
607 creating extra tree nodes when we don't have to. */
610 build_vtbl_ref_1 (tree instance, tree idx)
613 tree vtbl = NULL_TREE;
615 /* Try to figure out what a reference refers to, and
616 access its virtual function table directly. */
619 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
621 tree basetype = non_reference (TREE_TYPE (instance));
623 if (fixed_type && !cdtorp)
625 tree binfo = lookup_base (fixed_type, basetype,
626 ba_unique | ba_quiet, NULL);
628 vtbl = unshare_expr (BINFO_VTABLE (binfo));
632 vtbl = build_vfield_ref (instance, basetype);
634 aref = build_array_ref (input_location, vtbl, idx);
635 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
641 build_vtbl_ref (tree instance, tree idx)
643 tree aref = build_vtbl_ref_1 (instance, idx);
648 /* Given a stable object pointer INSTANCE_PTR, return an expression which
649 yields a function pointer corresponding to vtable element INDEX. */
652 build_vfn_ref (tree instance_ptr, tree idx)
656 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, RO_NULL,
657 tf_warning_or_error),
660 /* When using function descriptors, the address of the
661 vtable entry is treated as a function pointer. */
662 if (TARGET_VTABLE_USES_DESCRIPTORS)
663 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
664 cp_build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1,
665 tf_warning_or_error));
667 /* Remember this as a method reference, for later devirtualization. */
668 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
673 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
674 for the given TYPE. */
677 get_vtable_name (tree type)
679 return mangle_vtbl_for_type (type);
682 /* DECL is an entity associated with TYPE, like a virtual table or an
683 implicitly generated constructor. Determine whether or not DECL
684 should have external or internal linkage at the object file
685 level. This routine does not deal with COMDAT linkage and other
686 similar complexities; it simply sets TREE_PUBLIC if it possible for
687 entities in other translation units to contain copies of DECL, in
691 set_linkage_according_to_type (tree type, tree decl)
693 /* If TYPE involves a local class in a function with internal
694 linkage, then DECL should have internal linkage too. Other local
695 classes have no linkage -- but if their containing functions
696 have external linkage, it makes sense for DECL to have external
697 linkage too. That will allow template definitions to be merged,
699 if (no_linkage_check (type, /*relaxed_p=*/true))
701 TREE_PUBLIC (decl) = 0;
702 DECL_INTERFACE_KNOWN (decl) = 1;
705 TREE_PUBLIC (decl) = 1;
708 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
709 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
710 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
713 build_vtable (tree class_type, tree name, tree vtable_type)
717 decl = build_lang_decl (VAR_DECL, name, vtable_type);
718 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
719 now to avoid confusion in mangle_decl. */
720 SET_DECL_ASSEMBLER_NAME (decl, name);
721 DECL_CONTEXT (decl) = class_type;
722 DECL_ARTIFICIAL (decl) = 1;
723 TREE_STATIC (decl) = 1;
724 TREE_READONLY (decl) = 1;
725 DECL_VIRTUAL_P (decl) = 1;
726 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
727 DECL_VTABLE_OR_VTT_P (decl) = 1;
728 /* At one time the vtable info was grabbed 2 words at a time. This
729 fails on sparc unless you have 8-byte alignment. (tiemann) */
730 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
732 set_linkage_according_to_type (class_type, decl);
733 /* The vtable has not been defined -- yet. */
734 DECL_EXTERNAL (decl) = 1;
735 DECL_NOT_REALLY_EXTERN (decl) = 1;
737 /* Mark the VAR_DECL node representing the vtable itself as a
738 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
739 is rather important that such things be ignored because any
740 effort to actually generate DWARF for them will run into
741 trouble when/if we encounter code like:
744 struct S { virtual void member (); };
746 because the artificial declaration of the vtable itself (as
747 manufactured by the g++ front end) will say that the vtable is
748 a static member of `S' but only *after* the debug output for
749 the definition of `S' has already been output. This causes
750 grief because the DWARF entry for the definition of the vtable
751 will try to refer back to an earlier *declaration* of the
752 vtable as a static member of `S' and there won't be one. We
753 might be able to arrange to have the "vtable static member"
754 attached to the member list for `S' before the debug info for
755 `S' get written (which would solve the problem) but that would
756 require more intrusive changes to the g++ front end. */
757 DECL_IGNORED_P (decl) = 1;
762 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
763 or even complete. If this does not exist, create it. If COMPLETE is
764 nonzero, then complete the definition of it -- that will render it
765 impossible to actually build the vtable, but is useful to get at those
766 which are known to exist in the runtime. */
769 get_vtable_decl (tree type, int complete)
773 if (CLASSTYPE_VTABLES (type))
774 return CLASSTYPE_VTABLES (type);
776 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
777 CLASSTYPE_VTABLES (type) = decl;
781 DECL_EXTERNAL (decl) = 1;
782 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
788 /* Build the primary virtual function table for TYPE. If BINFO is
789 non-NULL, build the vtable starting with the initial approximation
790 that it is the same as the one which is the head of the association
791 list. Returns a nonzero value if a new vtable is actually
795 build_primary_vtable (tree binfo, tree type)
800 decl = get_vtable_decl (type, /*complete=*/0);
804 if (BINFO_NEW_VTABLE_MARKED (binfo))
805 /* We have already created a vtable for this base, so there's
806 no need to do it again. */
809 virtuals = copy_list (BINFO_VIRTUALS (binfo));
810 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
811 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
812 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
816 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
817 virtuals = NULL_TREE;
820 #ifdef GATHER_STATISTICS
822 n_vtable_elems += list_length (virtuals);
825 /* Initialize the association list for this type, based
826 on our first approximation. */
827 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
828 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
829 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
833 /* Give BINFO a new virtual function table which is initialized
834 with a skeleton-copy of its original initialization. The only
835 entry that changes is the `delta' entry, so we can really
836 share a lot of structure.
838 FOR_TYPE is the most derived type which caused this table to
841 Returns nonzero if we haven't met BINFO before.
843 The order in which vtables are built (by calling this function) for
844 an object must remain the same, otherwise a binary incompatibility
848 build_secondary_vtable (tree binfo)
850 if (BINFO_NEW_VTABLE_MARKED (binfo))
851 /* We already created a vtable for this base. There's no need to
855 /* Remember that we've created a vtable for this BINFO, so that we
856 don't try to do so again. */
857 SET_BINFO_NEW_VTABLE_MARKED (binfo);
859 /* Make fresh virtual list, so we can smash it later. */
860 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
862 /* Secondary vtables are laid out as part of the same structure as
863 the primary vtable. */
864 BINFO_VTABLE (binfo) = NULL_TREE;
868 /* Create a new vtable for BINFO which is the hierarchy dominated by
869 T. Return nonzero if we actually created a new vtable. */
872 make_new_vtable (tree t, tree binfo)
874 if (binfo == TYPE_BINFO (t))
875 /* In this case, it is *type*'s vtable we are modifying. We start
876 with the approximation that its vtable is that of the
877 immediate base class. */
878 return build_primary_vtable (binfo, t);
880 /* This is our very own copy of `basetype' to play with. Later,
881 we will fill in all the virtual functions that override the
882 virtual functions in these base classes which are not defined
883 by the current type. */
884 return build_secondary_vtable (binfo);
887 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
888 (which is in the hierarchy dominated by T) list FNDECL as its
889 BV_FN. DELTA is the required constant adjustment from the `this'
890 pointer where the vtable entry appears to the `this' required when
891 the function is actually called. */
894 modify_vtable_entry (tree t,
904 if (fndecl != BV_FN (v)
905 || !tree_int_cst_equal (delta, BV_DELTA (v)))
907 /* We need a new vtable for BINFO. */
908 if (make_new_vtable (t, binfo))
910 /* If we really did make a new vtable, we also made a copy
911 of the BINFO_VIRTUALS list. Now, we have to find the
912 corresponding entry in that list. */
913 *virtuals = BINFO_VIRTUALS (binfo);
914 while (BV_FN (*virtuals) != BV_FN (v))
915 *virtuals = TREE_CHAIN (*virtuals);
919 BV_DELTA (v) = delta;
920 BV_VCALL_INDEX (v) = NULL_TREE;
926 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
927 the USING_DECL naming METHOD. Returns true if the method could be
928 added to the method vec. */
931 add_method (tree type, tree method, tree using_decl)
935 bool template_conv_p = false;
937 VEC(tree,gc) *method_vec;
939 bool insert_p = false;
943 if (method == error_mark_node)
946 complete_p = COMPLETE_TYPE_P (type);
947 conv_p = DECL_CONV_FN_P (method);
949 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
950 && DECL_TEMPLATE_CONV_FN_P (method));
952 method_vec = CLASSTYPE_METHOD_VEC (type);
955 /* Make a new method vector. We start with 8 entries. We must
956 allocate at least two (for constructors and destructors), and
957 we're going to end up with an assignment operator at some
959 method_vec = VEC_alloc (tree, gc, 8);
960 /* Create slots for constructors and destructors. */
961 VEC_quick_push (tree, method_vec, NULL_TREE);
962 VEC_quick_push (tree, method_vec, NULL_TREE);
963 CLASSTYPE_METHOD_VEC (type) = method_vec;
966 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
967 grok_special_member_properties (method);
969 /* Constructors and destructors go in special slots. */
970 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
971 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
972 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
974 slot = CLASSTYPE_DESTRUCTOR_SLOT;
976 if (TYPE_FOR_JAVA (type))
978 if (!DECL_ARTIFICIAL (method))
979 error ("Java class %qT cannot have a destructor", type);
980 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
981 error ("Java class %qT cannot have an implicit non-trivial "
991 /* See if we already have an entry with this name. */
992 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
993 VEC_iterate (tree, method_vec, slot, m);
999 if (TREE_CODE (m) == TEMPLATE_DECL
1000 && DECL_TEMPLATE_CONV_FN_P (m))
1004 if (conv_p && !DECL_CONV_FN_P (m))
1006 if (DECL_NAME (m) == DECL_NAME (method))
1012 && !DECL_CONV_FN_P (m)
1013 && DECL_NAME (m) > DECL_NAME (method))
1017 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1019 /* Check to see if we've already got this method. */
1020 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1022 tree fn = OVL_CURRENT (fns);
1028 if (TREE_CODE (fn) != TREE_CODE (method))
1031 /* [over.load] Member function declarations with the
1032 same name and the same parameter types cannot be
1033 overloaded if any of them is a static member
1034 function declaration.
1036 [namespace.udecl] When a using-declaration brings names
1037 from a base class into a derived class scope, member
1038 functions in the derived class override and/or hide member
1039 functions with the same name and parameter types in a base
1040 class (rather than conflicting). */
1041 fn_type = TREE_TYPE (fn);
1042 method_type = TREE_TYPE (method);
1043 parms1 = TYPE_ARG_TYPES (fn_type);
1044 parms2 = TYPE_ARG_TYPES (method_type);
1046 /* Compare the quals on the 'this' parm. Don't compare
1047 the whole types, as used functions are treated as
1048 coming from the using class in overload resolution. */
1049 if (! DECL_STATIC_FUNCTION_P (fn)
1050 && ! DECL_STATIC_FUNCTION_P (method)
1051 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1052 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1053 && (cp_type_quals (TREE_TYPE (TREE_VALUE (parms1)))
1054 != cp_type_quals (TREE_TYPE (TREE_VALUE (parms2)))))
1057 /* For templates, the return type and template parameters
1058 must be identical. */
1059 if (TREE_CODE (fn) == TEMPLATE_DECL
1060 && (!same_type_p (TREE_TYPE (fn_type),
1061 TREE_TYPE (method_type))
1062 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1063 DECL_TEMPLATE_PARMS (method))))
1066 if (! DECL_STATIC_FUNCTION_P (fn))
1067 parms1 = TREE_CHAIN (parms1);
1068 if (! DECL_STATIC_FUNCTION_P (method))
1069 parms2 = TREE_CHAIN (parms2);
1071 if (compparms (parms1, parms2)
1072 && (!DECL_CONV_FN_P (fn)
1073 || same_type_p (TREE_TYPE (fn_type),
1074 TREE_TYPE (method_type))))
1078 if (DECL_CONTEXT (fn) == type)
1079 /* Defer to the local function. */
1081 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1082 error ("repeated using declaration %q+D", using_decl);
1084 error ("using declaration %q+D conflicts with a previous using declaration",
1089 error ("%q+#D cannot be overloaded", method);
1090 error ("with %q+#D", fn);
1093 /* We don't call duplicate_decls here to merge the
1094 declarations because that will confuse things if the
1095 methods have inline definitions. In particular, we
1096 will crash while processing the definitions. */
1101 /* A class should never have more than one destructor. */
1102 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1105 /* Add the new binding. */
1106 overload = build_overload (method, current_fns);
1109 TYPE_HAS_CONVERSION (type) = 1;
1110 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1111 push_class_level_binding (DECL_NAME (method), overload);
1117 /* We only expect to add few methods in the COMPLETE_P case, so
1118 just make room for one more method in that case. */
1120 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1122 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1124 CLASSTYPE_METHOD_VEC (type) = method_vec;
1125 if (slot == VEC_length (tree, method_vec))
1126 VEC_quick_push (tree, method_vec, overload);
1128 VEC_quick_insert (tree, method_vec, slot, overload);
1131 /* Replace the current slot. */
1132 VEC_replace (tree, method_vec, slot, overload);
1136 /* Subroutines of finish_struct. */
1138 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1139 legit, otherwise return 0. */
1142 alter_access (tree t, tree fdecl, tree access)
1146 if (!DECL_LANG_SPECIFIC (fdecl))
1147 retrofit_lang_decl (fdecl);
1149 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1151 elem = purpose_member (t, DECL_ACCESS (fdecl));
1154 if (TREE_VALUE (elem) != access)
1156 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1157 error ("conflicting access specifications for method"
1158 " %q+D, ignored", TREE_TYPE (fdecl));
1160 error ("conflicting access specifications for field %qE, ignored",
1165 /* They're changing the access to the same thing they changed
1166 it to before. That's OK. */
1172 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1173 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1179 /* Process the USING_DECL, which is a member of T. */
1182 handle_using_decl (tree using_decl, tree t)
1184 tree decl = USING_DECL_DECLS (using_decl);
1185 tree name = DECL_NAME (using_decl);
1187 = TREE_PRIVATE (using_decl) ? access_private_node
1188 : TREE_PROTECTED (using_decl) ? access_protected_node
1189 : access_public_node;
1190 tree flist = NULL_TREE;
1193 gcc_assert (!processing_template_decl && decl);
1195 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1198 if (is_overloaded_fn (old_value))
1199 old_value = OVL_CURRENT (old_value);
1201 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1204 old_value = NULL_TREE;
1207 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1209 if (is_overloaded_fn (decl))
1214 else if (is_overloaded_fn (old_value))
1217 /* It's OK to use functions from a base when there are functions with
1218 the same name already present in the current class. */;
1221 error ("%q+D invalid in %q#T", using_decl, t);
1222 error (" because of local method %q+#D with same name",
1223 OVL_CURRENT (old_value));
1227 else if (!DECL_ARTIFICIAL (old_value))
1229 error ("%q+D invalid in %q#T", using_decl, t);
1230 error (" because of local member %q+#D with same name", old_value);
1234 /* Make type T see field decl FDECL with access ACCESS. */
1236 for (; flist; flist = OVL_NEXT (flist))
1238 add_method (t, OVL_CURRENT (flist), using_decl);
1239 alter_access (t, OVL_CURRENT (flist), access);
1242 alter_access (t, decl, access);
1245 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1246 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1247 properties of the bases. */
1250 check_bases (tree t,
1251 int* cant_have_const_ctor_p,
1252 int* no_const_asn_ref_p)
1255 int seen_non_virtual_nearly_empty_base_p;
1258 tree field = NULL_TREE;
1260 seen_non_virtual_nearly_empty_base_p = 0;
1262 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1263 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1264 if (TREE_CODE (field) == FIELD_DECL)
1267 for (binfo = TYPE_BINFO (t), i = 0;
1268 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1270 tree basetype = TREE_TYPE (base_binfo);
1272 gcc_assert (COMPLETE_TYPE_P (basetype));
1274 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1275 here because the case of virtual functions but non-virtual
1276 dtor is handled in finish_struct_1. */
1277 if (!TYPE_POLYMORPHIC_P (basetype))
1278 warning (OPT_Weffc__,
1279 "base class %q#T has a non-virtual destructor", basetype);
1281 /* If the base class doesn't have copy constructors or
1282 assignment operators that take const references, then the
1283 derived class cannot have such a member automatically
1285 if (TYPE_HAS_COPY_CTOR (basetype)
1286 && ! TYPE_HAS_CONST_COPY_CTOR (basetype))
1287 *cant_have_const_ctor_p = 1;
1288 if (TYPE_HAS_COPY_ASSIGN (basetype)
1289 && !TYPE_HAS_CONST_COPY_ASSIGN (basetype))
1290 *no_const_asn_ref_p = 1;
1292 if (BINFO_VIRTUAL_P (base_binfo))
1293 /* A virtual base does not effect nearly emptiness. */
1295 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1297 if (seen_non_virtual_nearly_empty_base_p)
1298 /* And if there is more than one nearly empty base, then the
1299 derived class is not nearly empty either. */
1300 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1302 /* Remember we've seen one. */
1303 seen_non_virtual_nearly_empty_base_p = 1;
1305 else if (!is_empty_class (basetype))
1306 /* If the base class is not empty or nearly empty, then this
1307 class cannot be nearly empty. */
1308 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1310 /* A lot of properties from the bases also apply to the derived
1312 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1313 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1314 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1315 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
1316 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (basetype)
1317 || !TYPE_HAS_COPY_ASSIGN (basetype));
1318 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (basetype)
1319 || !TYPE_HAS_COPY_CTOR (basetype));
1320 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t)
1321 |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (basetype);
1322 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (basetype);
1323 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1324 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1325 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1326 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
1327 || TYPE_HAS_COMPLEX_DFLT (basetype));
1329 /* A standard-layout class is a class that:
1331 * has no non-standard-layout base classes, */
1332 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1333 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1336 /* ...has no base classes of the same type as the first non-static
1338 if (field && DECL_CONTEXT (field) == t
1339 && (same_type_ignoring_top_level_qualifiers_p
1340 (TREE_TYPE (field), basetype)))
1341 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1343 /* ...either has no non-static data members in the most-derived
1344 class and at most one base class with non-static data
1345 members, or has no base classes with non-static data
1347 for (basefield = TYPE_FIELDS (basetype); basefield;
1348 basefield = TREE_CHAIN (basefield))
1349 if (TREE_CODE (basefield) == FIELD_DECL)
1352 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1361 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1362 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1363 that have had a nearly-empty virtual primary base stolen by some
1364 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1368 determine_primary_bases (tree t)
1371 tree primary = NULL_TREE;
1372 tree type_binfo = TYPE_BINFO (t);
1375 /* Determine the primary bases of our bases. */
1376 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1377 base_binfo = TREE_CHAIN (base_binfo))
1379 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1381 /* See if we're the non-virtual primary of our inheritance
1383 if (!BINFO_VIRTUAL_P (base_binfo))
1385 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1386 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1389 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1390 BINFO_TYPE (parent_primary)))
1391 /* We are the primary binfo. */
1392 BINFO_PRIMARY_P (base_binfo) = 1;
1394 /* Determine if we have a virtual primary base, and mark it so.
1396 if (primary && BINFO_VIRTUAL_P (primary))
1398 tree this_primary = copied_binfo (primary, base_binfo);
1400 if (BINFO_PRIMARY_P (this_primary))
1401 /* Someone already claimed this base. */
1402 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1407 BINFO_PRIMARY_P (this_primary) = 1;
1408 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1410 /* A virtual binfo might have been copied from within
1411 another hierarchy. As we're about to use it as a
1412 primary base, make sure the offsets match. */
1413 delta = size_diffop_loc (input_location,
1415 BINFO_OFFSET (base_binfo)),
1417 BINFO_OFFSET (this_primary)));
1419 propagate_binfo_offsets (this_primary, delta);
1424 /* First look for a dynamic direct non-virtual base. */
1425 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1427 tree basetype = BINFO_TYPE (base_binfo);
1429 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1431 primary = base_binfo;
1436 /* A "nearly-empty" virtual base class can be the primary base
1437 class, if no non-virtual polymorphic base can be found. Look for
1438 a nearly-empty virtual dynamic base that is not already a primary
1439 base of something in the hierarchy. If there is no such base,
1440 just pick the first nearly-empty virtual base. */
1442 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1443 base_binfo = TREE_CHAIN (base_binfo))
1444 if (BINFO_VIRTUAL_P (base_binfo)
1445 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1447 if (!BINFO_PRIMARY_P (base_binfo))
1449 /* Found one that is not primary. */
1450 primary = base_binfo;
1454 /* Remember the first candidate. */
1455 primary = base_binfo;
1459 /* If we've got a primary base, use it. */
1462 tree basetype = BINFO_TYPE (primary);
1464 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1465 if (BINFO_PRIMARY_P (primary))
1466 /* We are stealing a primary base. */
1467 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1468 BINFO_PRIMARY_P (primary) = 1;
1469 if (BINFO_VIRTUAL_P (primary))
1473 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1474 /* A virtual binfo might have been copied from within
1475 another hierarchy. As we're about to use it as a primary
1476 base, make sure the offsets match. */
1477 delta = size_diffop_loc (input_location, ssize_int (0),
1478 convert (ssizetype, BINFO_OFFSET (primary)));
1480 propagate_binfo_offsets (primary, delta);
1483 primary = TYPE_BINFO (basetype);
1485 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1486 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1487 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1491 /* Update the variant types of T. */
1494 fixup_type_variants (tree t)
1501 for (variants = TYPE_NEXT_VARIANT (t);
1503 variants = TYPE_NEXT_VARIANT (variants))
1505 /* These fields are in the _TYPE part of the node, not in
1506 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1507 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1508 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1509 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1510 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1512 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1514 TYPE_BINFO (variants) = TYPE_BINFO (t);
1516 /* Copy whatever these are holding today. */
1517 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1518 TYPE_METHODS (variants) = TYPE_METHODS (t);
1519 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1521 /* All variants of a class have the same attributes. */
1522 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1527 /* Set memoizing fields and bits of T (and its variants) for later
1531 finish_struct_bits (tree t)
1533 /* Fix up variants (if any). */
1534 fixup_type_variants (t);
1536 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1537 /* For a class w/o baseclasses, 'finish_struct' has set
1538 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1539 Similarly for a class whose base classes do not have vtables.
1540 When neither of these is true, we might have removed abstract
1541 virtuals (by providing a definition), added some (by declaring
1542 new ones), or redeclared ones from a base class. We need to
1543 recalculate what's really an abstract virtual at this point (by
1544 looking in the vtables). */
1545 get_pure_virtuals (t);
1547 /* If this type has a copy constructor or a destructor, force its
1548 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1549 nonzero. This will cause it to be passed by invisible reference
1550 and prevent it from being returned in a register. */
1551 if (type_has_nontrivial_copy_init (t)
1552 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1555 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1556 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1558 SET_TYPE_MODE (variants, BLKmode);
1559 TREE_ADDRESSABLE (variants) = 1;
1564 /* Issue warnings about T having private constructors, but no friends,
1567 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1568 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1569 non-private static member functions. */
1572 maybe_warn_about_overly_private_class (tree t)
1574 int has_member_fn = 0;
1575 int has_nonprivate_method = 0;
1578 if (!warn_ctor_dtor_privacy
1579 /* If the class has friends, those entities might create and
1580 access instances, so we should not warn. */
1581 || (CLASSTYPE_FRIEND_CLASSES (t)
1582 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1583 /* We will have warned when the template was declared; there's
1584 no need to warn on every instantiation. */
1585 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1586 /* There's no reason to even consider warning about this
1590 /* We only issue one warning, if more than one applies, because
1591 otherwise, on code like:
1594 // Oops - forgot `public:'
1600 we warn several times about essentially the same problem. */
1602 /* Check to see if all (non-constructor, non-destructor) member
1603 functions are private. (Since there are no friends or
1604 non-private statics, we can't ever call any of the private member
1606 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1607 /* We're not interested in compiler-generated methods; they don't
1608 provide any way to call private members. */
1609 if (!DECL_ARTIFICIAL (fn))
1611 if (!TREE_PRIVATE (fn))
1613 if (DECL_STATIC_FUNCTION_P (fn))
1614 /* A non-private static member function is just like a
1615 friend; it can create and invoke private member
1616 functions, and be accessed without a class
1620 has_nonprivate_method = 1;
1621 /* Keep searching for a static member function. */
1623 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1627 if (!has_nonprivate_method && has_member_fn)
1629 /* There are no non-private methods, and there's at least one
1630 private member function that isn't a constructor or
1631 destructor. (If all the private members are
1632 constructors/destructors we want to use the code below that
1633 issues error messages specifically referring to
1634 constructors/destructors.) */
1636 tree binfo = TYPE_BINFO (t);
1638 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1639 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1641 has_nonprivate_method = 1;
1644 if (!has_nonprivate_method)
1646 warning (OPT_Wctor_dtor_privacy,
1647 "all member functions in class %qT are private", t);
1652 /* Even if some of the member functions are non-private, the class
1653 won't be useful for much if all the constructors or destructors
1654 are private: such an object can never be created or destroyed. */
1655 fn = CLASSTYPE_DESTRUCTORS (t);
1656 if (fn && TREE_PRIVATE (fn))
1658 warning (OPT_Wctor_dtor_privacy,
1659 "%q#T only defines a private destructor and has no friends",
1664 /* Warn about classes that have private constructors and no friends. */
1665 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1666 /* Implicitly generated constructors are always public. */
1667 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1668 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1670 int nonprivate_ctor = 0;
1672 /* If a non-template class does not define a copy
1673 constructor, one is defined for it, enabling it to avoid
1674 this warning. For a template class, this does not
1675 happen, and so we would normally get a warning on:
1677 template <class T> class C { private: C(); };
1679 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1680 complete non-template or fully instantiated classes have this
1682 if (!TYPE_HAS_COPY_CTOR (t))
1683 nonprivate_ctor = 1;
1685 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1687 tree ctor = OVL_CURRENT (fn);
1688 /* Ideally, we wouldn't count copy constructors (or, in
1689 fact, any constructor that takes an argument of the
1690 class type as a parameter) because such things cannot
1691 be used to construct an instance of the class unless
1692 you already have one. But, for now at least, we're
1694 if (! TREE_PRIVATE (ctor))
1696 nonprivate_ctor = 1;
1701 if (nonprivate_ctor == 0)
1703 warning (OPT_Wctor_dtor_privacy,
1704 "%q#T only defines private constructors and has no friends",
1712 gt_pointer_operator new_value;
1716 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1719 method_name_cmp (const void* m1_p, const void* m2_p)
1721 const tree *const m1 = (const tree *) m1_p;
1722 const tree *const m2 = (const tree *) m2_p;
1724 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1726 if (*m1 == NULL_TREE)
1728 if (*m2 == NULL_TREE)
1730 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1735 /* This routine compares two fields like method_name_cmp but using the
1736 pointer operator in resort_field_decl_data. */
1739 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1741 const tree *const m1 = (const tree *) m1_p;
1742 const tree *const m2 = (const tree *) m2_p;
1743 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1745 if (*m1 == NULL_TREE)
1747 if (*m2 == NULL_TREE)
1750 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1751 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1752 resort_data.new_value (&d1, resort_data.cookie);
1753 resort_data.new_value (&d2, resort_data.cookie);
1760 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1763 resort_type_method_vec (void* obj,
1764 void* orig_obj ATTRIBUTE_UNUSED ,
1765 gt_pointer_operator new_value,
1768 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1769 int len = VEC_length (tree, method_vec);
1773 /* The type conversion ops have to live at the front of the vec, so we
1775 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1776 VEC_iterate (tree, method_vec, slot, fn);
1778 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1783 resort_data.new_value = new_value;
1784 resort_data.cookie = cookie;
1785 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1786 resort_method_name_cmp);
1790 /* Warn about duplicate methods in fn_fields.
1792 Sort methods that are not special (i.e., constructors, destructors,
1793 and type conversion operators) so that we can find them faster in
1797 finish_struct_methods (tree t)
1800 VEC(tree,gc) *method_vec;
1803 method_vec = CLASSTYPE_METHOD_VEC (t);
1807 len = VEC_length (tree, method_vec);
1809 /* Clear DECL_IN_AGGR_P for all functions. */
1810 for (fn_fields = TYPE_METHODS (t); fn_fields;
1811 fn_fields = TREE_CHAIN (fn_fields))
1812 DECL_IN_AGGR_P (fn_fields) = 0;
1814 /* Issue warnings about private constructors and such. If there are
1815 no methods, then some public defaults are generated. */
1816 maybe_warn_about_overly_private_class (t);
1818 /* The type conversion ops have to live at the front of the vec, so we
1820 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1821 VEC_iterate (tree, method_vec, slot, fn_fields);
1823 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1826 qsort (VEC_address (tree, method_vec) + slot,
1827 len-slot, sizeof (tree), method_name_cmp);
1830 /* Make BINFO's vtable have N entries, including RTTI entries,
1831 vbase and vcall offsets, etc. Set its type and call the back end
1835 layout_vtable_decl (tree binfo, int n)
1840 atype = build_cplus_array_type (vtable_entry_type,
1841 build_index_type (size_int (n - 1)));
1842 layout_type (atype);
1844 /* We may have to grow the vtable. */
1845 vtable = get_vtbl_decl_for_binfo (binfo);
1846 if (!same_type_p (TREE_TYPE (vtable), atype))
1848 TREE_TYPE (vtable) = atype;
1849 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1850 layout_decl (vtable, 0);
1854 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1855 have the same signature. */
1858 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1860 /* One destructor overrides another if they are the same kind of
1862 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1863 && special_function_p (base_fndecl) == special_function_p (fndecl))
1865 /* But a non-destructor never overrides a destructor, nor vice
1866 versa, nor do different kinds of destructors override
1867 one-another. For example, a complete object destructor does not
1868 override a deleting destructor. */
1869 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1872 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1873 || (DECL_CONV_FN_P (fndecl)
1874 && DECL_CONV_FN_P (base_fndecl)
1875 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1876 DECL_CONV_FN_TYPE (base_fndecl))))
1878 tree types, base_types;
1879 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1880 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1881 if ((cp_type_quals (TREE_TYPE (TREE_VALUE (base_types)))
1882 == cp_type_quals (TREE_TYPE (TREE_VALUE (types))))
1883 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1889 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1893 base_derived_from (tree derived, tree base)
1897 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1899 if (probe == derived)
1901 else if (BINFO_VIRTUAL_P (probe))
1902 /* If we meet a virtual base, we can't follow the inheritance
1903 any more. See if the complete type of DERIVED contains
1904 such a virtual base. */
1905 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1911 typedef struct find_final_overrider_data_s {
1912 /* The function for which we are trying to find a final overrider. */
1914 /* The base class in which the function was declared. */
1915 tree declaring_base;
1916 /* The candidate overriders. */
1918 /* Path to most derived. */
1919 VEC(tree,heap) *path;
1920 } find_final_overrider_data;
1922 /* Add the overrider along the current path to FFOD->CANDIDATES.
1923 Returns true if an overrider was found; false otherwise. */
1926 dfs_find_final_overrider_1 (tree binfo,
1927 find_final_overrider_data *ffod,
1932 /* If BINFO is not the most derived type, try a more derived class.
1933 A definition there will overrider a definition here. */
1937 if (dfs_find_final_overrider_1
1938 (VEC_index (tree, ffod->path, depth), ffod, depth))
1942 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1945 tree *candidate = &ffod->candidates;
1947 /* Remove any candidates overridden by this new function. */
1950 /* If *CANDIDATE overrides METHOD, then METHOD
1951 cannot override anything else on the list. */
1952 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1954 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1955 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1956 *candidate = TREE_CHAIN (*candidate);
1958 candidate = &TREE_CHAIN (*candidate);
1961 /* Add the new function. */
1962 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1969 /* Called from find_final_overrider via dfs_walk. */
1972 dfs_find_final_overrider_pre (tree binfo, void *data)
1974 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1976 if (binfo == ffod->declaring_base)
1977 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1978 VEC_safe_push (tree, heap, ffod->path, binfo);
1984 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1986 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1987 VEC_pop (tree, ffod->path);
1992 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1993 FN and whose TREE_VALUE is the binfo for the base where the
1994 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1995 DERIVED) is the base object in which FN is declared. */
1998 find_final_overrider (tree derived, tree binfo, tree fn)
2000 find_final_overrider_data ffod;
2002 /* Getting this right is a little tricky. This is valid:
2004 struct S { virtual void f (); };
2005 struct T { virtual void f (); };
2006 struct U : public S, public T { };
2008 even though calling `f' in `U' is ambiguous. But,
2010 struct R { virtual void f(); };
2011 struct S : virtual public R { virtual void f (); };
2012 struct T : virtual public R { virtual void f (); };
2013 struct U : public S, public T { };
2015 is not -- there's no way to decide whether to put `S::f' or
2016 `T::f' in the vtable for `R'.
2018 The solution is to look at all paths to BINFO. If we find
2019 different overriders along any two, then there is a problem. */
2020 if (DECL_THUNK_P (fn))
2021 fn = THUNK_TARGET (fn);
2023 /* Determine the depth of the hierarchy. */
2025 ffod.declaring_base = binfo;
2026 ffod.candidates = NULL_TREE;
2027 ffod.path = VEC_alloc (tree, heap, 30);
2029 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2030 dfs_find_final_overrider_post, &ffod);
2032 VEC_free (tree, heap, ffod.path);
2034 /* If there was no winner, issue an error message. */
2035 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2036 return error_mark_node;
2038 return ffod.candidates;
2041 /* Return the index of the vcall offset for FN when TYPE is used as a
2045 get_vcall_index (tree fn, tree type)
2047 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2051 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
2052 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2053 || same_signature_p (fn, p->purpose))
2056 /* There should always be an appropriate index. */
2060 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2061 dominated by T. FN is the old function; VIRTUALS points to the
2062 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2063 of that entry in the list. */
2066 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2074 tree overrider_fn, overrider_target;
2075 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2076 tree over_return, base_return;
2079 /* Find the nearest primary base (possibly binfo itself) which defines
2080 this function; this is the class the caller will convert to when
2081 calling FN through BINFO. */
2082 for (b = binfo; ; b = get_primary_binfo (b))
2085 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2088 /* The nearest definition is from a lost primary. */
2089 if (BINFO_LOST_PRIMARY_P (b))
2094 /* Find the final overrider. */
2095 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2096 if (overrider == error_mark_node)
2098 error ("no unique final overrider for %qD in %qT", target_fn, t);
2101 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2103 /* Check for adjusting covariant return types. */
2104 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2105 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2107 if (POINTER_TYPE_P (over_return)
2108 && TREE_CODE (over_return) == TREE_CODE (base_return)
2109 && CLASS_TYPE_P (TREE_TYPE (over_return))
2110 && CLASS_TYPE_P (TREE_TYPE (base_return))
2111 /* If the overrider is invalid, don't even try. */
2112 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2114 /* If FN is a covariant thunk, we must figure out the adjustment
2115 to the final base FN was converting to. As OVERRIDER_TARGET might
2116 also be converting to the return type of FN, we have to
2117 combine the two conversions here. */
2118 tree fixed_offset, virtual_offset;
2120 over_return = TREE_TYPE (over_return);
2121 base_return = TREE_TYPE (base_return);
2123 if (DECL_THUNK_P (fn))
2125 gcc_assert (DECL_RESULT_THUNK_P (fn));
2126 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2127 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2130 fixed_offset = virtual_offset = NULL_TREE;
2133 /* Find the equivalent binfo within the return type of the
2134 overriding function. We will want the vbase offset from
2136 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2138 else if (!same_type_ignoring_top_level_qualifiers_p
2139 (over_return, base_return))
2141 /* There was no existing virtual thunk (which takes
2142 precedence). So find the binfo of the base function's
2143 return type within the overriding function's return type.
2144 We cannot call lookup base here, because we're inside a
2145 dfs_walk, and will therefore clobber the BINFO_MARKED
2146 flags. Fortunately we know the covariancy is valid (it
2147 has already been checked), so we can just iterate along
2148 the binfos, which have been chained in inheritance graph
2149 order. Of course it is lame that we have to repeat the
2150 search here anyway -- we should really be caching pieces
2151 of the vtable and avoiding this repeated work. */
2152 tree thunk_binfo, base_binfo;
2154 /* Find the base binfo within the overriding function's
2155 return type. We will always find a thunk_binfo, except
2156 when the covariancy is invalid (which we will have
2157 already diagnosed). */
2158 for (base_binfo = TYPE_BINFO (base_return),
2159 thunk_binfo = TYPE_BINFO (over_return);
2161 thunk_binfo = TREE_CHAIN (thunk_binfo))
2162 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2163 BINFO_TYPE (base_binfo)))
2166 /* See if virtual inheritance is involved. */
2167 for (virtual_offset = thunk_binfo;
2169 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2170 if (BINFO_VIRTUAL_P (virtual_offset))
2174 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2176 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2180 /* We convert via virtual base. Adjust the fixed
2181 offset to be from there. */
2183 size_diffop (offset,
2185 BINFO_OFFSET (virtual_offset)));
2188 /* There was an existing fixed offset, this must be
2189 from the base just converted to, and the base the
2190 FN was thunking to. */
2191 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2193 fixed_offset = offset;
2197 if (fixed_offset || virtual_offset)
2198 /* Replace the overriding function with a covariant thunk. We
2199 will emit the overriding function in its own slot as
2201 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2202 fixed_offset, virtual_offset);
2205 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2206 !DECL_THUNK_P (fn));
2208 /* If we need a covariant thunk, then we may need to adjust first_defn.
2209 The ABI specifies that the thunks emitted with a function are
2210 determined by which bases the function overrides, so we need to be
2211 sure that we're using a thunk for some overridden base; even if we
2212 know that the necessary this adjustment is zero, there may not be an
2213 appropriate zero-this-adjusment thunk for us to use since thunks for
2214 overriding virtual bases always use the vcall offset.
2216 Furthermore, just choosing any base that overrides this function isn't
2217 quite right, as this slot won't be used for calls through a type that
2218 puts a covariant thunk here. Calling the function through such a type
2219 will use a different slot, and that slot is the one that determines
2220 the thunk emitted for that base.
2222 So, keep looking until we find the base that we're really overriding
2223 in this slot: the nearest primary base that doesn't use a covariant
2224 thunk in this slot. */
2225 if (overrider_target != overrider_fn)
2227 if (BINFO_TYPE (b) == DECL_CONTEXT (overrider_target))
2228 /* We already know that the overrider needs a covariant thunk. */
2229 b = get_primary_binfo (b);
2230 for (; ; b = get_primary_binfo (b))
2232 tree main_binfo = TYPE_BINFO (BINFO_TYPE (b));
2233 tree bv = chain_index (ix, BINFO_VIRTUALS (main_binfo));
2234 if (BINFO_LOST_PRIMARY_P (b))
2236 if (!DECL_THUNK_P (TREE_VALUE (bv)))
2242 /* Assume that we will produce a thunk that convert all the way to
2243 the final overrider, and not to an intermediate virtual base. */
2244 virtual_base = NULL_TREE;
2246 /* See if we can convert to an intermediate virtual base first, and then
2247 use the vcall offset located there to finish the conversion. */
2248 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2250 /* If we find the final overrider, then we can stop
2252 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2253 BINFO_TYPE (TREE_VALUE (overrider))))
2256 /* If we find a virtual base, and we haven't yet found the
2257 overrider, then there is a virtual base between the
2258 declaring base (first_defn) and the final overrider. */
2259 if (BINFO_VIRTUAL_P (b))
2266 /* Compute the constant adjustment to the `this' pointer. The
2267 `this' pointer, when this function is called, will point at BINFO
2268 (or one of its primary bases, which are at the same offset). */
2270 /* The `this' pointer needs to be adjusted from the declaration to
2271 the nearest virtual base. */
2272 delta = size_diffop_loc (input_location,
2273 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2274 convert (ssizetype, BINFO_OFFSET (first_defn)));
2276 /* If the nearest definition is in a lost primary, we don't need an
2277 entry in our vtable. Except possibly in a constructor vtable,
2278 if we happen to get our primary back. In that case, the offset
2279 will be zero, as it will be a primary base. */
2280 delta = size_zero_node;
2282 /* The `this' pointer needs to be adjusted from pointing to
2283 BINFO to pointing at the base where the final overrider
2285 delta = size_diffop_loc (input_location,
2287 BINFO_OFFSET (TREE_VALUE (overrider))),
2288 convert (ssizetype, BINFO_OFFSET (binfo)));
2290 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2293 BV_VCALL_INDEX (*virtuals)
2294 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2296 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2299 BV_LOST_PRIMARY (*virtuals) = true;
2302 /* Called from modify_all_vtables via dfs_walk. */
2305 dfs_modify_vtables (tree binfo, void* data)
2307 tree t = (tree) data;
2312 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2313 /* A base without a vtable needs no modification, and its bases
2314 are uninteresting. */
2315 return dfs_skip_bases;
2317 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2318 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2319 /* Don't do the primary vtable, if it's new. */
2322 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2323 /* There's no need to modify the vtable for a non-virtual primary
2324 base; we're not going to use that vtable anyhow. We do still
2325 need to do this for virtual primary bases, as they could become
2326 non-primary in a construction vtable. */
2329 make_new_vtable (t, binfo);
2331 /* Now, go through each of the virtual functions in the virtual
2332 function table for BINFO. Find the final overrider, and update
2333 the BINFO_VIRTUALS list appropriately. */
2334 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2335 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2337 ix++, virtuals = TREE_CHAIN (virtuals),
2338 old_virtuals = TREE_CHAIN (old_virtuals))
2339 update_vtable_entry_for_fn (t,
2341 BV_FN (old_virtuals),
2347 /* Update all of the primary and secondary vtables for T. Create new
2348 vtables as required, and initialize their RTTI information. Each
2349 of the functions in VIRTUALS is declared in T and may override a
2350 virtual function from a base class; find and modify the appropriate
2351 entries to point to the overriding functions. Returns a list, in
2352 declaration order, of the virtual functions that are declared in T,
2353 but do not appear in the primary base class vtable, and which
2354 should therefore be appended to the end of the vtable for T. */
2357 modify_all_vtables (tree t, tree virtuals)
2359 tree binfo = TYPE_BINFO (t);
2362 /* Update all of the vtables. */
2363 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2365 /* Add virtual functions not already in our primary vtable. These
2366 will be both those introduced by this class, and those overridden
2367 from secondary bases. It does not include virtuals merely
2368 inherited from secondary bases. */
2369 for (fnsp = &virtuals; *fnsp; )
2371 tree fn = TREE_VALUE (*fnsp);
2373 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2374 || DECL_VINDEX (fn) == error_mark_node)
2376 /* We don't need to adjust the `this' pointer when
2377 calling this function. */
2378 BV_DELTA (*fnsp) = integer_zero_node;
2379 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2381 /* This is a function not already in our vtable. Keep it. */
2382 fnsp = &TREE_CHAIN (*fnsp);
2385 /* We've already got an entry for this function. Skip it. */
2386 *fnsp = TREE_CHAIN (*fnsp);
2392 /* Get the base virtual function declarations in T that have the
2396 get_basefndecls (tree name, tree t)
2399 tree base_fndecls = NULL_TREE;
2400 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2403 /* Find virtual functions in T with the indicated NAME. */
2404 i = lookup_fnfields_1 (t, name);
2406 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2408 methods = OVL_NEXT (methods))
2410 tree method = OVL_CURRENT (methods);
2412 if (TREE_CODE (method) == FUNCTION_DECL
2413 && DECL_VINDEX (method))
2414 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2418 return base_fndecls;
2420 for (i = 0; i < n_baseclasses; i++)
2422 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2423 base_fndecls = chainon (get_basefndecls (name, basetype),
2427 return base_fndecls;
2430 /* If this declaration supersedes the declaration of
2431 a method declared virtual in the base class, then
2432 mark this field as being virtual as well. */
2435 check_for_override (tree decl, tree ctype)
2437 if (TREE_CODE (decl) == TEMPLATE_DECL)
2438 /* In [temp.mem] we have:
2440 A specialization of a member function template does not
2441 override a virtual function from a base class. */
2443 if ((DECL_DESTRUCTOR_P (decl)
2444 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2445 || DECL_CONV_FN_P (decl))
2446 && look_for_overrides (ctype, decl)
2447 && !DECL_STATIC_FUNCTION_P (decl))
2448 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2449 the error_mark_node so that we know it is an overriding
2451 DECL_VINDEX (decl) = decl;
2453 if (DECL_VIRTUAL_P (decl))
2455 if (!DECL_VINDEX (decl))
2456 DECL_VINDEX (decl) = error_mark_node;
2457 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2461 /* Warn about hidden virtual functions that are not overridden in t.
2462 We know that constructors and destructors don't apply. */
2465 warn_hidden (tree t)
2467 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2471 /* We go through each separately named virtual function. */
2472 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2473 VEC_iterate (tree, method_vec, i, fns);
2484 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2485 have the same name. Figure out what name that is. */
2486 name = DECL_NAME (OVL_CURRENT (fns));
2487 /* There are no possibly hidden functions yet. */
2488 base_fndecls = NULL_TREE;
2489 /* Iterate through all of the base classes looking for possibly
2490 hidden functions. */
2491 for (binfo = TYPE_BINFO (t), j = 0;
2492 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2494 tree basetype = BINFO_TYPE (base_binfo);
2495 base_fndecls = chainon (get_basefndecls (name, basetype),
2499 /* If there are no functions to hide, continue. */
2503 /* Remove any overridden functions. */
2504 for (fn = fns; fn; fn = OVL_NEXT (fn))
2506 fndecl = OVL_CURRENT (fn);
2507 if (DECL_VINDEX (fndecl))
2509 tree *prev = &base_fndecls;
2512 /* If the method from the base class has the same
2513 signature as the method from the derived class, it
2514 has been overridden. */
2515 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2516 *prev = TREE_CHAIN (*prev);
2518 prev = &TREE_CHAIN (*prev);
2522 /* Now give a warning for all base functions without overriders,
2523 as they are hidden. */
2524 while (base_fndecls)
2526 /* Here we know it is a hider, and no overrider exists. */
2527 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2528 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2529 base_fndecls = TREE_CHAIN (base_fndecls);
2534 /* Check for things that are invalid. There are probably plenty of other
2535 things we should check for also. */
2538 finish_struct_anon (tree t)
2542 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2544 if (TREE_STATIC (field))
2546 if (TREE_CODE (field) != FIELD_DECL)
2549 if (DECL_NAME (field) == NULL_TREE
2550 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2552 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2553 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2554 for (; elt; elt = TREE_CHAIN (elt))
2556 /* We're generally only interested in entities the user
2557 declared, but we also find nested classes by noticing
2558 the TYPE_DECL that we create implicitly. You're
2559 allowed to put one anonymous union inside another,
2560 though, so we explicitly tolerate that. We use
2561 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2562 we also allow unnamed types used for defining fields. */
2563 if (DECL_ARTIFICIAL (elt)
2564 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2565 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2568 if (TREE_CODE (elt) != FIELD_DECL)
2571 permerror (input_location, "%q+#D invalid; an anonymous union can "
2572 "only have non-static data members", elt);
2574 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2575 "only have non-static data members", elt);
2579 if (TREE_PRIVATE (elt))
2582 permerror (input_location, "private member %q+#D in anonymous union", elt);
2584 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2586 else if (TREE_PROTECTED (elt))
2589 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2591 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2594 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2595 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2601 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2602 will be used later during class template instantiation.
2603 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2604 a non-static member data (FIELD_DECL), a member function
2605 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2606 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2607 When FRIEND_P is nonzero, T is either a friend class
2608 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2609 (FUNCTION_DECL, TEMPLATE_DECL). */
2612 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2614 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2615 if (CLASSTYPE_TEMPLATE_INFO (type))
2616 CLASSTYPE_DECL_LIST (type)
2617 = tree_cons (friend_p ? NULL_TREE : type,
2618 t, CLASSTYPE_DECL_LIST (type));
2621 /* Create default constructors, assignment operators, and so forth for
2622 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2623 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2624 the class cannot have a default constructor, copy constructor
2625 taking a const reference argument, or an assignment operator taking
2626 a const reference, respectively. */
2629 add_implicitly_declared_members (tree t,
2630 int cant_have_const_cctor,
2631 int cant_have_const_assignment)
2634 if (!CLASSTYPE_DESTRUCTORS (t))
2636 /* In general, we create destructors lazily. */
2637 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2639 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2640 && TYPE_FOR_JAVA (t))
2641 /* But if this is a Java class, any non-trivial destructor is
2642 invalid, even if compiler-generated. Therefore, if the
2643 destructor is non-trivial we create it now. */
2644 lazily_declare_fn (sfk_destructor, t);
2649 If there is no user-declared constructor for a class, a default
2650 constructor is implicitly declared. */
2651 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2653 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2654 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2659 If a class definition does not explicitly declare a copy
2660 constructor, one is declared implicitly. */
2661 if (! TYPE_HAS_COPY_CTOR (t) && ! TYPE_FOR_JAVA (t)
2662 && !type_has_move_constructor (t))
2664 TYPE_HAS_COPY_CTOR (t) = 1;
2665 TYPE_HAS_CONST_COPY_CTOR (t) = !cant_have_const_cctor;
2666 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2667 if (cxx_dialect >= cxx0x)
2668 CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
2671 /* If there is no assignment operator, one will be created if and
2672 when it is needed. For now, just record whether or not the type
2673 of the parameter to the assignment operator will be a const or
2674 non-const reference. */
2675 if (!TYPE_HAS_COPY_ASSIGN (t) && !TYPE_FOR_JAVA (t)
2676 && !type_has_move_assign (t))
2678 TYPE_HAS_COPY_ASSIGN (t) = 1;
2679 TYPE_HAS_CONST_COPY_ASSIGN (t) = !cant_have_const_assignment;
2680 CLASSTYPE_LAZY_COPY_ASSIGN (t) = 1;
2681 if (cxx_dialect >= cxx0x)
2682 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 1;
2685 /* We can't be lazy about declaring functions that might override
2686 a virtual function from a base class. */
2687 if (TYPE_POLYMORPHIC_P (t)
2688 && (CLASSTYPE_LAZY_COPY_ASSIGN (t)
2689 || CLASSTYPE_LAZY_MOVE_ASSIGN (t)
2690 || CLASSTYPE_LAZY_DESTRUCTOR (t)))
2692 tree binfo = TYPE_BINFO (t);
2695 tree opname = ansi_assopname (NOP_EXPR);
2696 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ++ix)
2699 for (bv = BINFO_VIRTUALS (base_binfo); bv; bv = TREE_CHAIN (bv))
2701 tree fn = BV_FN (bv);
2702 if (DECL_NAME (fn) == opname)
2704 if (CLASSTYPE_LAZY_COPY_ASSIGN (t))
2705 lazily_declare_fn (sfk_copy_assignment, t);
2706 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
2707 lazily_declare_fn (sfk_move_assignment, t);
2709 else if (DECL_DESTRUCTOR_P (fn)
2710 && CLASSTYPE_LAZY_DESTRUCTOR (t))
2711 lazily_declare_fn (sfk_destructor, t);
2717 /* Subroutine of finish_struct_1. Recursively count the number of fields
2718 in TYPE, including anonymous union members. */
2721 count_fields (tree fields)
2725 for (x = fields; x; x = TREE_CHAIN (x))
2727 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2728 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2735 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2736 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2739 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2742 for (x = fields; x; x = TREE_CHAIN (x))
2744 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2745 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2747 field_vec->elts[idx++] = x;
2752 /* FIELD is a bit-field. We are finishing the processing for its
2753 enclosing type. Issue any appropriate messages and set appropriate
2754 flags. Returns false if an error has been diagnosed. */
2757 check_bitfield_decl (tree field)
2759 tree type = TREE_TYPE (field);
2762 /* Extract the declared width of the bitfield, which has been
2763 temporarily stashed in DECL_INITIAL. */
2764 w = DECL_INITIAL (field);
2765 gcc_assert (w != NULL_TREE);
2766 /* Remove the bit-field width indicator so that the rest of the
2767 compiler does not treat that value as an initializer. */
2768 DECL_INITIAL (field) = NULL_TREE;
2770 /* Detect invalid bit-field type. */
2771 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2773 error ("bit-field %q+#D with non-integral type", field);
2774 w = error_mark_node;
2778 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2781 /* detect invalid field size. */
2782 w = integral_constant_value (w);
2784 if (TREE_CODE (w) != INTEGER_CST)
2786 error ("bit-field %q+D width not an integer constant", field);
2787 w = error_mark_node;
2789 else if (tree_int_cst_sgn (w) < 0)
2791 error ("negative width in bit-field %q+D", field);
2792 w = error_mark_node;
2794 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2796 error ("zero width for bit-field %q+D", field);
2797 w = error_mark_node;
2799 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2800 && TREE_CODE (type) != ENUMERAL_TYPE
2801 && TREE_CODE (type) != BOOLEAN_TYPE)
2802 warning (0, "width of %q+D exceeds its type", field);
2803 else if (TREE_CODE (type) == ENUMERAL_TYPE
2804 && (0 > (compare_tree_int
2805 (w, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type))))))
2806 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2809 if (w != error_mark_node)
2811 DECL_SIZE (field) = convert (bitsizetype, w);
2812 DECL_BIT_FIELD (field) = 1;
2817 /* Non-bit-fields are aligned for their type. */
2818 DECL_BIT_FIELD (field) = 0;
2819 CLEAR_DECL_C_BIT_FIELD (field);
2824 /* FIELD is a non bit-field. We are finishing the processing for its
2825 enclosing type T. Issue any appropriate messages and set appropriate
2829 check_field_decl (tree field,
2831 int* cant_have_const_ctor,
2832 int* no_const_asn_ref,
2833 int* any_default_members)
2835 tree type = strip_array_types (TREE_TYPE (field));
2837 /* An anonymous union cannot contain any fields which would change
2838 the settings of CANT_HAVE_CONST_CTOR and friends. */
2839 if (ANON_UNION_TYPE_P (type))
2841 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2842 structs. So, we recurse through their fields here. */
2843 else if (ANON_AGGR_TYPE_P (type))
2847 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2848 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2849 check_field_decl (fields, t, cant_have_const_ctor,
2850 no_const_asn_ref, any_default_members);
2852 /* Check members with class type for constructors, destructors,
2854 else if (CLASS_TYPE_P (type))
2856 /* Never let anything with uninheritable virtuals
2857 make it through without complaint. */
2858 abstract_virtuals_error (field, type);
2860 if (TREE_CODE (t) == UNION_TYPE)
2862 if (TYPE_NEEDS_CONSTRUCTING (type))
2863 error ("member %q+#D with constructor not allowed in union",
2865 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2866 error ("member %q+#D with destructor not allowed in union", field);
2867 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
2868 error ("member %q+#D with copy assignment operator not allowed in union",
2870 /* Don't bother diagnosing move assop now; C++0x has more
2875 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2876 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2877 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2878 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
2879 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type)
2880 || !TYPE_HAS_COPY_ASSIGN (type));
2881 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type)
2882 || !TYPE_HAS_COPY_CTOR (type));
2883 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type);
2884 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type);
2885 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type)
2886 || TYPE_HAS_COMPLEX_DFLT (type));
2889 if (TYPE_HAS_COPY_CTOR (type)
2890 && !TYPE_HAS_CONST_COPY_CTOR (type))
2891 *cant_have_const_ctor = 1;
2893 if (TYPE_HAS_COPY_ASSIGN (type)
2894 && !TYPE_HAS_CONST_COPY_ASSIGN (type))
2895 *no_const_asn_ref = 1;
2897 if (DECL_INITIAL (field) != NULL_TREE)
2899 /* `build_class_init_list' does not recognize
2901 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2902 error ("multiple fields in union %qT initialized", t);
2903 *any_default_members = 1;
2907 /* Check the data members (both static and non-static), class-scoped
2908 typedefs, etc., appearing in the declaration of T. Issue
2909 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2910 declaration order) of access declarations; each TREE_VALUE in this
2911 list is a USING_DECL.
2913 In addition, set the following flags:
2916 The class is empty, i.e., contains no non-static data members.
2918 CANT_HAVE_CONST_CTOR_P
2919 This class cannot have an implicitly generated copy constructor
2920 taking a const reference.
2922 CANT_HAVE_CONST_ASN_REF
2923 This class cannot have an implicitly generated assignment
2924 operator taking a const reference.
2926 All of these flags should be initialized before calling this
2929 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2930 fields can be added by adding to this chain. */
2933 check_field_decls (tree t, tree *access_decls,
2934 int *cant_have_const_ctor_p,
2935 int *no_const_asn_ref_p)
2940 int any_default_members;
2942 int field_access = -1;
2944 /* Assume there are no access declarations. */
2945 *access_decls = NULL_TREE;
2946 /* Assume this class has no pointer members. */
2947 has_pointers = false;
2948 /* Assume none of the members of this class have default
2950 any_default_members = 0;
2952 for (field = &TYPE_FIELDS (t); *field; field = next)
2955 tree type = TREE_TYPE (x);
2956 int this_field_access;
2958 next = &TREE_CHAIN (x);
2960 if (TREE_CODE (x) == USING_DECL)
2962 /* Prune the access declaration from the list of fields. */
2963 *field = TREE_CHAIN (x);
2965 /* Save the access declarations for our caller. */
2966 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2968 /* Since we've reset *FIELD there's no reason to skip to the
2974 if (TREE_CODE (x) == TYPE_DECL
2975 || TREE_CODE (x) == TEMPLATE_DECL)
2978 /* If we've gotten this far, it's a data member, possibly static,
2979 or an enumerator. */
2980 DECL_CONTEXT (x) = t;
2982 /* When this goes into scope, it will be a non-local reference. */
2983 DECL_NONLOCAL (x) = 1;
2985 if (TREE_CODE (t) == UNION_TYPE)
2989 If a union contains a static data member, or a member of
2990 reference type, the program is ill-formed. */
2991 if (TREE_CODE (x) == VAR_DECL)
2993 error ("%q+D may not be static because it is a member of a union", x);
2996 if (TREE_CODE (type) == REFERENCE_TYPE)
2998 error ("%q+D may not have reference type %qT because"
2999 " it is a member of a union",
3005 /* Perform error checking that did not get done in
3007 if (TREE_CODE (type) == FUNCTION_TYPE)
3009 error ("field %q+D invalidly declared function type", x);
3010 type = build_pointer_type (type);
3011 TREE_TYPE (x) = type;
3013 else if (TREE_CODE (type) == METHOD_TYPE)
3015 error ("field %q+D invalidly declared method type", x);
3016 type = build_pointer_type (type);
3017 TREE_TYPE (x) = type;
3020 if (type == error_mark_node)
3023 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
3026 /* Now it can only be a FIELD_DECL. */
3028 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3029 CLASSTYPE_NON_AGGREGATE (t) = 1;
3031 /* A standard-layout class is a class that:
3033 has the same access control (Clause 11) for all non-static data members,
3035 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3036 if (field_access == -1)
3037 field_access = this_field_access;
3038 else if (this_field_access != field_access)
3039 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3041 /* If this is of reference type, check if it needs an init. */
3042 if (TREE_CODE (type) == REFERENCE_TYPE)
3044 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3045 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3046 if (DECL_INITIAL (x) == NULL_TREE)
3047 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3049 /* ARM $12.6.2: [A member initializer list] (or, for an
3050 aggregate, initialization by a brace-enclosed list) is the
3051 only way to initialize nonstatic const and reference
3053 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3054 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3057 type = strip_array_types (type);
3059 if (TYPE_PACKED (t))
3061 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3065 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3069 else if (DECL_C_BIT_FIELD (x)
3070 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3071 DECL_PACKED (x) = 1;
3074 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3075 /* We don't treat zero-width bitfields as making a class
3080 /* The class is non-empty. */
3081 CLASSTYPE_EMPTY_P (t) = 0;
3082 /* The class is not even nearly empty. */
3083 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3084 /* If one of the data members contains an empty class,
3086 if (CLASS_TYPE_P (type)
3087 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3088 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3091 /* This is used by -Weffc++ (see below). Warn only for pointers
3092 to members which might hold dynamic memory. So do not warn
3093 for pointers to functions or pointers to members. */
3094 if (TYPE_PTR_P (type)
3095 && !TYPE_PTRFN_P (type)
3096 && !TYPE_PTR_TO_MEMBER_P (type))
3097 has_pointers = true;
3099 if (CLASS_TYPE_P (type))
3101 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3102 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3103 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3104 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3107 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3108 CLASSTYPE_HAS_MUTABLE (t) = 1;
3110 if (! layout_pod_type_p (type))
3111 /* DR 148 now allows pointers to members (which are POD themselves),
3112 to be allowed in POD structs. */
3113 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3115 if (!std_layout_type_p (type))
3116 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3118 if (! zero_init_p (type))
3119 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3121 /* We set DECL_C_BIT_FIELD in grokbitfield.
3122 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3123 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3124 check_field_decl (x, t,
3125 cant_have_const_ctor_p,
3127 &any_default_members);
3129 /* If any field is const, the structure type is pseudo-const. */
3130 if (CP_TYPE_CONST_P (type))
3132 C_TYPE_FIELDS_READONLY (t) = 1;
3133 if (DECL_INITIAL (x) == NULL_TREE)
3134 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3136 /* ARM $12.6.2: [A member initializer list] (or, for an
3137 aggregate, initialization by a brace-enclosed list) is the
3138 only way to initialize nonstatic const and reference
3140 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3141 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3143 /* A field that is pseudo-const makes the structure likewise. */
3144 else if (CLASS_TYPE_P (type))
3146 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3147 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3148 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3149 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3152 /* Core issue 80: A nonstatic data member is required to have a
3153 different name from the class iff the class has a
3154 user-declared constructor. */
3155 if (constructor_name_p (DECL_NAME (x), t)
3156 && TYPE_HAS_USER_CONSTRUCTOR (t))
3157 permerror (input_location, "field %q+#D with same name as class", x);
3160 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3161 it should also define a copy constructor and an assignment operator to
3162 implement the correct copy semantic (deep vs shallow, etc.). As it is
3163 not feasible to check whether the constructors do allocate dynamic memory
3164 and store it within members, we approximate the warning like this:
3166 -- Warn only if there are members which are pointers
3167 -- Warn only if there is a non-trivial constructor (otherwise,
3168 there cannot be memory allocated).
3169 -- Warn only if there is a non-trivial destructor. We assume that the
3170 user at least implemented the cleanup correctly, and a destructor
3171 is needed to free dynamic memory.
3173 This seems enough for practical purposes. */
3176 && TYPE_HAS_USER_CONSTRUCTOR (t)
3177 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3178 && !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
3180 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3182 if (! TYPE_HAS_COPY_CTOR (t))
3184 warning (OPT_Weffc__,
3185 " but does not override %<%T(const %T&)%>", t, t);
3186 if (!TYPE_HAS_COPY_ASSIGN (t))
3187 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3189 else if (! TYPE_HAS_COPY_ASSIGN (t))
3190 warning (OPT_Weffc__,
3191 " but does not override %<operator=(const %T&)%>", t);
3194 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3196 TYPE_PACKED (t) = 0;
3198 /* Check anonymous struct/anonymous union fields. */
3199 finish_struct_anon (t);
3201 /* We've built up the list of access declarations in reverse order.
3203 *access_decls = nreverse (*access_decls);
3206 /* If TYPE is an empty class type, records its OFFSET in the table of
3210 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3214 if (!is_empty_class (type))
3217 /* Record the location of this empty object in OFFSETS. */
3218 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3220 n = splay_tree_insert (offsets,
3221 (splay_tree_key) offset,
3222 (splay_tree_value) NULL_TREE);
3223 n->value = ((splay_tree_value)
3224 tree_cons (NULL_TREE,
3231 /* Returns nonzero if TYPE is an empty class type and there is
3232 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3235 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3240 if (!is_empty_class (type))
3243 /* Record the location of this empty object in OFFSETS. */
3244 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3248 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3249 if (same_type_p (TREE_VALUE (t), type))
3255 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3256 F for every subobject, passing it the type, offset, and table of
3257 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3260 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3261 than MAX_OFFSET will not be walked.
3263 If F returns a nonzero value, the traversal ceases, and that value
3264 is returned. Otherwise, returns zero. */
3267 walk_subobject_offsets (tree type,
3268 subobject_offset_fn f,
3275 tree type_binfo = NULL_TREE;
3277 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3279 if (max_offset && INT_CST_LT (max_offset, offset))
3282 if (type == error_mark_node)
3287 if (abi_version_at_least (2))
3289 type = BINFO_TYPE (type);
3292 if (CLASS_TYPE_P (type))
3298 /* Avoid recursing into objects that are not interesting. */
3299 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3302 /* Record the location of TYPE. */
3303 r = (*f) (type, offset, offsets);
3307 /* Iterate through the direct base classes of TYPE. */
3309 type_binfo = TYPE_BINFO (type);
3310 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3314 if (abi_version_at_least (2)
3315 && BINFO_VIRTUAL_P (binfo))
3319 && BINFO_VIRTUAL_P (binfo)
3320 && !BINFO_PRIMARY_P (binfo))
3323 if (!abi_version_at_least (2))
3324 binfo_offset = size_binop (PLUS_EXPR,
3326 BINFO_OFFSET (binfo));
3330 /* We cannot rely on BINFO_OFFSET being set for the base
3331 class yet, but the offsets for direct non-virtual
3332 bases can be calculated by going back to the TYPE. */
3333 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3334 binfo_offset = size_binop (PLUS_EXPR,
3336 BINFO_OFFSET (orig_binfo));
3339 r = walk_subobject_offsets (binfo,
3344 (abi_version_at_least (2)
3345 ? /*vbases_p=*/0 : vbases_p));
3350 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3353 VEC(tree,gc) *vbases;
3355 /* Iterate through the virtual base classes of TYPE. In G++
3356 3.2, we included virtual bases in the direct base class
3357 loop above, which results in incorrect results; the
3358 correct offsets for virtual bases are only known when
3359 working with the most derived type. */
3361 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3362 VEC_iterate (tree, vbases, ix, binfo); ix++)
3364 r = walk_subobject_offsets (binfo,
3366 size_binop (PLUS_EXPR,
3368 BINFO_OFFSET (binfo)),
3377 /* We still have to walk the primary base, if it is
3378 virtual. (If it is non-virtual, then it was walked
3380 tree vbase = get_primary_binfo (type_binfo);
3382 if (vbase && BINFO_VIRTUAL_P (vbase)
3383 && BINFO_PRIMARY_P (vbase)
3384 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3386 r = (walk_subobject_offsets
3388 offsets, max_offset, /*vbases_p=*/0));
3395 /* Iterate through the fields of TYPE. */
3396 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3397 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3401 if (abi_version_at_least (2))
3402 field_offset = byte_position (field);
3404 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3405 field_offset = DECL_FIELD_OFFSET (field);
3407 r = walk_subobject_offsets (TREE_TYPE (field),
3409 size_binop (PLUS_EXPR,
3419 else if (TREE_CODE (type) == ARRAY_TYPE)
3421 tree element_type = strip_array_types (type);
3422 tree domain = TYPE_DOMAIN (type);
3425 /* Avoid recursing into objects that are not interesting. */
3426 if (!CLASS_TYPE_P (element_type)
3427 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3430 /* Step through each of the elements in the array. */
3431 for (index = size_zero_node;
3432 /* G++ 3.2 had an off-by-one error here. */
3433 (abi_version_at_least (2)
3434 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3435 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3436 index = size_binop (PLUS_EXPR, index, size_one_node))
3438 r = walk_subobject_offsets (TREE_TYPE (type),
3446 offset = size_binop (PLUS_EXPR, offset,
3447 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3448 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3449 there's no point in iterating through the remaining
3450 elements of the array. */
3451 if (max_offset && INT_CST_LT (max_offset, offset))
3459 /* Record all of the empty subobjects of TYPE (either a type or a
3460 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3461 is being placed at OFFSET; otherwise, it is a base class that is
3462 being placed at OFFSET. */
3465 record_subobject_offsets (tree type,
3468 bool is_data_member)
3471 /* If recording subobjects for a non-static data member or a
3472 non-empty base class , we do not need to record offsets beyond
3473 the size of the biggest empty class. Additional data members
3474 will go at the end of the class. Additional base classes will go
3475 either at offset zero (if empty, in which case they cannot
3476 overlap with offsets past the size of the biggest empty class) or
3477 at the end of the class.
3479 However, if we are placing an empty base class, then we must record
3480 all offsets, as either the empty class is at offset zero (where
3481 other empty classes might later be placed) or at the end of the
3482 class (where other objects might then be placed, so other empty
3483 subobjects might later overlap). */
3485 || !is_empty_class (BINFO_TYPE (type)))
3486 max_offset = sizeof_biggest_empty_class;
3488 max_offset = NULL_TREE;
3489 walk_subobject_offsets (type, record_subobject_offset, offset,
3490 offsets, max_offset, is_data_member);
3493 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3494 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3495 virtual bases of TYPE are examined. */
3498 layout_conflict_p (tree type,
3503 splay_tree_node max_node;
3505 /* Get the node in OFFSETS that indicates the maximum offset where
3506 an empty subobject is located. */
3507 max_node = splay_tree_max (offsets);
3508 /* If there aren't any empty subobjects, then there's no point in
3509 performing this check. */
3513 return walk_subobject_offsets (type, check_subobject_offset, offset,
3514 offsets, (tree) (max_node->key),
3518 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3519 non-static data member of the type indicated by RLI. BINFO is the
3520 binfo corresponding to the base subobject, OFFSETS maps offsets to
3521 types already located at those offsets. This function determines
3522 the position of the DECL. */
3525 layout_nonempty_base_or_field (record_layout_info rli,
3530 tree offset = NULL_TREE;
3536 /* For the purposes of determining layout conflicts, we want to
3537 use the class type of BINFO; TREE_TYPE (DECL) will be the
3538 CLASSTYPE_AS_BASE version, which does not contain entries for
3539 zero-sized bases. */
3540 type = TREE_TYPE (binfo);
3545 type = TREE_TYPE (decl);
3549 /* Try to place the field. It may take more than one try if we have
3550 a hard time placing the field without putting two objects of the
3551 same type at the same address. */
3554 struct record_layout_info_s old_rli = *rli;
3556 /* Place this field. */
3557 place_field (rli, decl);
3558 offset = byte_position (decl);
3560 /* We have to check to see whether or not there is already
3561 something of the same type at the offset we're about to use.
3562 For example, consider:
3565 struct T : public S { int i; };
3566 struct U : public S, public T {};
3568 Here, we put S at offset zero in U. Then, we can't put T at
3569 offset zero -- its S component would be at the same address
3570 as the S we already allocated. So, we have to skip ahead.
3571 Since all data members, including those whose type is an
3572 empty class, have nonzero size, any overlap can happen only
3573 with a direct or indirect base-class -- it can't happen with
3575 /* In a union, overlap is permitted; all members are placed at
3577 if (TREE_CODE (rli->t) == UNION_TYPE)
3579 /* G++ 3.2 did not check for overlaps when placing a non-empty
3581 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3583 if (layout_conflict_p (field_p ? type : binfo, offset,
3586 /* Strip off the size allocated to this field. That puts us
3587 at the first place we could have put the field with
3588 proper alignment. */
3591 /* Bump up by the alignment required for the type. */
3593 = size_binop (PLUS_EXPR, rli->bitpos,
3595 ? CLASSTYPE_ALIGN (type)
3596 : TYPE_ALIGN (type)));
3597 normalize_rli (rli);
3600 /* There was no conflict. We're done laying out this field. */
3604 /* Now that we know where it will be placed, update its
3606 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3607 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3608 this point because their BINFO_OFFSET is copied from another
3609 hierarchy. Therefore, we may not need to add the entire
3611 propagate_binfo_offsets (binfo,
3612 size_diffop_loc (input_location,
3613 convert (ssizetype, offset),
3615 BINFO_OFFSET (binfo))));
3618 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3621 empty_base_at_nonzero_offset_p (tree type,
3623 splay_tree offsets ATTRIBUTE_UNUSED)
3625 return is_empty_class (type) && !integer_zerop (offset);
3628 /* Layout the empty base BINFO. EOC indicates the byte currently just
3629 past the end of the class, and should be correctly aligned for a
3630 class of the type indicated by BINFO; OFFSETS gives the offsets of
3631 the empty bases allocated so far. T is the most derived
3632 type. Return nonzero iff we added it at the end. */
3635 layout_empty_base (record_layout_info rli, tree binfo,
3636 tree eoc, splay_tree offsets)
3639 tree basetype = BINFO_TYPE (binfo);
3642 /* This routine should only be used for empty classes. */
3643 gcc_assert (is_empty_class (basetype));
3644 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3646 if (!integer_zerop (BINFO_OFFSET (binfo)))
3648 if (abi_version_at_least (2))
3649 propagate_binfo_offsets
3650 (binfo, size_diffop_loc (input_location,
3651 size_zero_node, BINFO_OFFSET (binfo)));
3654 "offset of empty base %qT may not be ABI-compliant and may"
3655 "change in a future version of GCC",
3656 BINFO_TYPE (binfo));
3659 /* This is an empty base class. We first try to put it at offset
3661 if (layout_conflict_p (binfo,
3662 BINFO_OFFSET (binfo),
3666 /* That didn't work. Now, we move forward from the next
3667 available spot in the class. */
3669 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3672 if (!layout_conflict_p (binfo,
3673 BINFO_OFFSET (binfo),
3676 /* We finally found a spot where there's no overlap. */
3679 /* There's overlap here, too. Bump along to the next spot. */
3680 propagate_binfo_offsets (binfo, alignment);
3684 if (CLASSTYPE_USER_ALIGN (basetype))
3686 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3688 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3689 TYPE_USER_ALIGN (rli->t) = 1;
3695 /* Layout the base given by BINFO in the class indicated by RLI.
3696 *BASE_ALIGN is a running maximum of the alignments of
3697 any base class. OFFSETS gives the location of empty base
3698 subobjects. T is the most derived type. Return nonzero if the new
3699 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3700 *NEXT_FIELD, unless BINFO is for an empty base class.
3702 Returns the location at which the next field should be inserted. */
3705 build_base_field (record_layout_info rli, tree binfo,
3706 splay_tree offsets, tree *next_field)
3709 tree basetype = BINFO_TYPE (binfo);
3711 if (!COMPLETE_TYPE_P (basetype))
3712 /* This error is now reported in xref_tag, thus giving better
3713 location information. */
3716 /* Place the base class. */
3717 if (!is_empty_class (basetype))
3721 /* The containing class is non-empty because it has a non-empty
3723 CLASSTYPE_EMPTY_P (t) = 0;
3725 /* Create the FIELD_DECL. */
3726 decl = build_decl (input_location,
3727 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3728 DECL_ARTIFICIAL (decl) = 1;
3729 DECL_IGNORED_P (decl) = 1;
3730 DECL_FIELD_CONTEXT (decl) = t;
3731 if (CLASSTYPE_AS_BASE (basetype))
3733 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3734 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3735 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3736 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3737 DECL_MODE (decl) = TYPE_MODE (basetype);
3738 DECL_FIELD_IS_BASE (decl) = 1;
3740 /* Try to place the field. It may take more than one try if we
3741 have a hard time placing the field without putting two
3742 objects of the same type at the same address. */
3743 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3744 /* Add the new FIELD_DECL to the list of fields for T. */
3745 TREE_CHAIN (decl) = *next_field;
3747 next_field = &TREE_CHAIN (decl);
3755 /* On some platforms (ARM), even empty classes will not be
3757 eoc = round_up_loc (input_location,
3758 rli_size_unit_so_far (rli),
3759 CLASSTYPE_ALIGN_UNIT (basetype));
3760 atend = layout_empty_base (rli, binfo, eoc, offsets);
3761 /* A nearly-empty class "has no proper base class that is empty,
3762 not morally virtual, and at an offset other than zero." */
3763 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3766 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3767 /* The check above (used in G++ 3.2) is insufficient because
3768 an empty class placed at offset zero might itself have an
3769 empty base at a nonzero offset. */
3770 else if (walk_subobject_offsets (basetype,
3771 empty_base_at_nonzero_offset_p,
3774 /*max_offset=*/NULL_TREE,
3777 if (abi_version_at_least (2))
3778 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3781 "class %qT will be considered nearly empty in a "
3782 "future version of GCC", t);
3786 /* We do not create a FIELD_DECL for empty base classes because
3787 it might overlap some other field. We want to be able to
3788 create CONSTRUCTORs for the class by iterating over the
3789 FIELD_DECLs, and the back end does not handle overlapping
3792 /* An empty virtual base causes a class to be non-empty
3793 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3794 here because that was already done when the virtual table
3795 pointer was created. */
3798 /* Record the offsets of BINFO and its base subobjects. */
3799 record_subobject_offsets (binfo,
3800 BINFO_OFFSET (binfo),
3802 /*is_data_member=*/false);
3807 /* Layout all of the non-virtual base classes. Record empty
3808 subobjects in OFFSETS. T is the most derived type. Return nonzero
3809 if the type cannot be nearly empty. The fields created
3810 corresponding to the base classes will be inserted at
3814 build_base_fields (record_layout_info rli,
3815 splay_tree offsets, tree *next_field)
3817 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3820 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3823 /* The primary base class is always allocated first. */
3824 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3825 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3826 offsets, next_field);
3828 /* Now allocate the rest of the bases. */
3829 for (i = 0; i < n_baseclasses; ++i)
3833 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3835 /* The primary base was already allocated above, so we don't
3836 need to allocate it again here. */
3837 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3840 /* Virtual bases are added at the end (a primary virtual base
3841 will have already been added). */
3842 if (BINFO_VIRTUAL_P (base_binfo))
3845 next_field = build_base_field (rli, base_binfo,
3846 offsets, next_field);
3850 /* Go through the TYPE_METHODS of T issuing any appropriate
3851 diagnostics, figuring out which methods override which other
3852 methods, and so forth. */
3855 check_methods (tree t)
3859 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3861 check_for_override (x, t);
3862 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3863 error ("initializer specified for non-virtual method %q+D", x);
3864 /* The name of the field is the original field name
3865 Save this in auxiliary field for later overloading. */
3866 if (DECL_VINDEX (x))
3868 TYPE_POLYMORPHIC_P (t) = 1;
3869 if (DECL_PURE_VIRTUAL_P (x))
3870 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3872 /* All user-provided destructors are non-trivial.
3873 Constructors and assignment ops are handled in
3874 grok_special_member_properties. */
3875 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
3876 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3880 /* FN is a constructor or destructor. Clone the declaration to create
3881 a specialized in-charge or not-in-charge version, as indicated by
3885 build_clone (tree fn, tree name)
3890 /* Copy the function. */
3891 clone = copy_decl (fn);
3892 /* Reset the function name. */
3893 DECL_NAME (clone) = name;
3894 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3895 /* Remember where this function came from. */
3896 DECL_ABSTRACT_ORIGIN (clone) = fn;
3897 /* Make it easy to find the CLONE given the FN. */
3898 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3899 TREE_CHAIN (fn) = clone;
3901 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3902 if (TREE_CODE (clone) == TEMPLATE_DECL)
3904 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3905 DECL_TEMPLATE_RESULT (clone) = result;
3906 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3907 DECL_TI_TEMPLATE (result) = clone;
3908 TREE_TYPE (clone) = TREE_TYPE (result);
3912 DECL_CLONED_FUNCTION (clone) = fn;
3913 /* There's no pending inline data for this function. */
3914 DECL_PENDING_INLINE_INFO (clone) = NULL;
3915 DECL_PENDING_INLINE_P (clone) = 0;
3917 /* The base-class destructor is not virtual. */
3918 if (name == base_dtor_identifier)
3920 DECL_VIRTUAL_P (clone) = 0;
3921 if (TREE_CODE (clone) != TEMPLATE_DECL)
3922 DECL_VINDEX (clone) = NULL_TREE;
3925 /* If there was an in-charge parameter, drop it from the function
3927 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3933 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3934 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3935 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3936 /* Skip the `this' parameter. */
3937 parmtypes = TREE_CHAIN (parmtypes);
3938 /* Skip the in-charge parameter. */
3939 parmtypes = TREE_CHAIN (parmtypes);
3940 /* And the VTT parm, in a complete [cd]tor. */
3941 if (DECL_HAS_VTT_PARM_P (fn)
3942 && ! DECL_NEEDS_VTT_PARM_P (clone))
3943 parmtypes = TREE_CHAIN (parmtypes);
3944 /* If this is subobject constructor or destructor, add the vtt
3947 = build_method_type_directly (basetype,
3948 TREE_TYPE (TREE_TYPE (clone)),
3951 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3954 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3955 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3958 /* Copy the function parameters. */
3959 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3960 /* Remove the in-charge parameter. */
3961 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3963 TREE_CHAIN (DECL_ARGUMENTS (clone))
3964 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3965 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3967 /* And the VTT parm, in a complete [cd]tor. */
3968 if (DECL_HAS_VTT_PARM_P (fn))
3970 if (DECL_NEEDS_VTT_PARM_P (clone))
3971 DECL_HAS_VTT_PARM_P (clone) = 1;
3974 TREE_CHAIN (DECL_ARGUMENTS (clone))
3975 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3976 DECL_HAS_VTT_PARM_P (clone) = 0;
3980 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3982 DECL_CONTEXT (parms) = clone;
3983 cxx_dup_lang_specific_decl (parms);
3986 /* Create the RTL for this function. */
3987 SET_DECL_RTL (clone, NULL);
3988 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3991 note_decl_for_pch (clone);
3996 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
3997 not invoke this function directly.
3999 For a non-thunk function, returns the address of the slot for storing
4000 the function it is a clone of. Otherwise returns NULL_TREE.
4002 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4003 cloned_function is unset. This is to support the separate
4004 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4005 on a template makes sense, but not the former. */
4008 decl_cloned_function_p (const_tree decl, bool just_testing)
4012 decl = STRIP_TEMPLATE (decl);
4014 if (TREE_CODE (decl) != FUNCTION_DECL
4015 || !DECL_LANG_SPECIFIC (decl)
4016 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
4018 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4020 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
4026 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
4027 if (just_testing && *ptr == NULL_TREE)
4033 /* Produce declarations for all appropriate clones of FN. If
4034 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4035 CLASTYPE_METHOD_VEC as well. */
4038 clone_function_decl (tree fn, int update_method_vec_p)
4042 /* Avoid inappropriate cloning. */
4044 && DECL_CLONED_FUNCTION_P (TREE_CHAIN (fn)))
4047 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4049 /* For each constructor, we need two variants: an in-charge version
4050 and a not-in-charge version. */
4051 clone = build_clone (fn, complete_ctor_identifier);
4052 if (update_method_vec_p)
4053 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4054 clone = build_clone (fn, base_ctor_identifier);
4055 if (update_method_vec_p)
4056 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4060 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4062 /* For each destructor, we need three variants: an in-charge
4063 version, a not-in-charge version, and an in-charge deleting
4064 version. We clone the deleting version first because that
4065 means it will go second on the TYPE_METHODS list -- and that
4066 corresponds to the correct layout order in the virtual
4069 For a non-virtual destructor, we do not build a deleting
4071 if (DECL_VIRTUAL_P (fn))
4073 clone = build_clone (fn, deleting_dtor_identifier);
4074 if (update_method_vec_p)
4075 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4077 clone = build_clone (fn, complete_dtor_identifier);
4078 if (update_method_vec_p)
4079 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4080 clone = build_clone (fn, base_dtor_identifier);
4081 if (update_method_vec_p)
4082 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4085 /* Note that this is an abstract function that is never emitted. */
4086 DECL_ABSTRACT (fn) = 1;
4089 /* DECL is an in charge constructor, which is being defined. This will
4090 have had an in class declaration, from whence clones were
4091 declared. An out-of-class definition can specify additional default
4092 arguments. As it is the clones that are involved in overload
4093 resolution, we must propagate the information from the DECL to its
4097 adjust_clone_args (tree decl)
4101 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4102 clone = TREE_CHAIN (clone))
4104 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4105 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4106 tree decl_parms, clone_parms;
4108 clone_parms = orig_clone_parms;
4110 /* Skip the 'this' parameter. */
4111 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4112 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4114 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4115 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4116 if (DECL_HAS_VTT_PARM_P (decl))
4117 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4119 clone_parms = orig_clone_parms;
4120 if (DECL_HAS_VTT_PARM_P (clone))
4121 clone_parms = TREE_CHAIN (clone_parms);
4123 for (decl_parms = orig_decl_parms; decl_parms;
4124 decl_parms = TREE_CHAIN (decl_parms),
4125 clone_parms = TREE_CHAIN (clone_parms))
4127 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4128 TREE_TYPE (clone_parms)));
4130 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4132 /* A default parameter has been added. Adjust the
4133 clone's parameters. */
4134 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4135 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4136 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4139 clone_parms = orig_decl_parms;
4141 if (DECL_HAS_VTT_PARM_P (clone))
4143 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4144 TREE_VALUE (orig_clone_parms),
4146 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4148 type = build_method_type_directly (basetype,
4149 TREE_TYPE (TREE_TYPE (clone)),
4152 type = build_exception_variant (type, exceptions);
4154 type = cp_build_type_attribute_variant (type, attrs);
4155 TREE_TYPE (clone) = type;
4157 clone_parms = NULL_TREE;
4161 gcc_assert (!clone_parms);
4165 /* For each of the constructors and destructors in T, create an
4166 in-charge and not-in-charge variant. */
4169 clone_constructors_and_destructors (tree t)
4173 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4175 if (!CLASSTYPE_METHOD_VEC (t))
4178 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4179 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4180 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4181 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4184 /* Returns true iff class T has a user-defined constructor other than
4185 the default constructor. */
4188 type_has_user_nondefault_constructor (tree t)
4192 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4195 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4197 tree fn = OVL_CURRENT (fns);
4198 if (!DECL_ARTIFICIAL (fn)
4199 && (TREE_CODE (fn) == TEMPLATE_DECL
4200 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4208 /* Returns the defaulted constructor if T has one. Otherwise, returns
4212 in_class_defaulted_default_constructor (tree t)
4216 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4219 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4221 tree fn = OVL_CURRENT (fns);
4223 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4225 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4226 while (args && TREE_PURPOSE (args))
4227 args = TREE_CHAIN (args);
4228 if (!args || args == void_list_node)
4236 /* Returns true iff FN is a user-provided function, i.e. user-declared
4237 and not defaulted at its first declaration; or explicit, private,
4238 protected, or non-const. */
4241 user_provided_p (tree fn)
4243 if (TREE_CODE (fn) == TEMPLATE_DECL)
4246 return (!DECL_ARTIFICIAL (fn)
4247 && !DECL_DEFAULTED_IN_CLASS_P (fn));
4250 /* Returns true iff class T has a user-provided constructor. */
4253 type_has_user_provided_constructor (tree t)
4257 if (!CLASS_TYPE_P (t))
4260 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4263 /* This can happen in error cases; avoid crashing. */
4264 if (!CLASSTYPE_METHOD_VEC (t))
4267 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4268 if (user_provided_p (OVL_CURRENT (fns)))
4274 /* Returns true iff class T has a user-provided default constructor. */
4277 type_has_user_provided_default_constructor (tree t)
4281 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4284 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4286 tree fn = OVL_CURRENT (fns);
4287 if (TREE_CODE (fn) == FUNCTION_DECL
4288 && user_provided_p (fn)
4289 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)))
4296 /* Returns true iff class TYPE has a virtual destructor. */
4299 type_has_virtual_destructor (tree type)
4303 if (!CLASS_TYPE_P (type))
4306 gcc_assert (COMPLETE_TYPE_P (type));
4307 dtor = CLASSTYPE_DESTRUCTORS (type);
4308 return (dtor && DECL_VIRTUAL_P (dtor));
4311 /* Returns true iff class T has a move constructor. */
4314 type_has_move_constructor (tree t)
4318 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4320 gcc_assert (COMPLETE_TYPE_P (t));
4321 lazily_declare_fn (sfk_move_constructor, t);
4324 if (!CLASSTYPE_METHOD_VEC (t))
4327 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4328 if (move_fn_p (OVL_CURRENT (fns)))
4334 /* Returns true iff class T has a move assignment operator. */
4337 type_has_move_assign (tree t)
4341 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4343 gcc_assert (COMPLETE_TYPE_P (t));
4344 lazily_declare_fn (sfk_move_assignment, t);
4347 for (fns = lookup_fnfields_slot (t, ansi_assopname (NOP_EXPR));
4348 fns; fns = OVL_NEXT (fns))
4349 if (move_fn_p (OVL_CURRENT (fns)))
4355 /* Remove all zero-width bit-fields from T. */
4358 remove_zero_width_bit_fields (tree t)
4362 fieldsp = &TYPE_FIELDS (t);
4365 if (TREE_CODE (*fieldsp) == FIELD_DECL
4366 && DECL_C_BIT_FIELD (*fieldsp)
4367 /* We should not be confused by the fact that grokbitfield
4368 temporarily sets the width of the bit field into
4369 DECL_INITIAL (*fieldsp).
4370 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4372 && integer_zerop (DECL_SIZE (*fieldsp)))
4373 *fieldsp = TREE_CHAIN (*fieldsp);
4375 fieldsp = &TREE_CHAIN (*fieldsp);
4379 /* Returns TRUE iff we need a cookie when dynamically allocating an
4380 array whose elements have the indicated class TYPE. */
4383 type_requires_array_cookie (tree type)
4386 bool has_two_argument_delete_p = false;
4388 gcc_assert (CLASS_TYPE_P (type));
4390 /* If there's a non-trivial destructor, we need a cookie. In order
4391 to iterate through the array calling the destructor for each
4392 element, we'll have to know how many elements there are. */
4393 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4396 /* If the usual deallocation function is a two-argument whose second
4397 argument is of type `size_t', then we have to pass the size of
4398 the array to the deallocation function, so we will need to store
4400 fns = lookup_fnfields (TYPE_BINFO (type),
4401 ansi_opname (VEC_DELETE_EXPR),
4403 /* If there are no `operator []' members, or the lookup is
4404 ambiguous, then we don't need a cookie. */
4405 if (!fns || fns == error_mark_node)
4407 /* Loop through all of the functions. */
4408 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4413 /* Select the current function. */
4414 fn = OVL_CURRENT (fns);
4415 /* See if this function is a one-argument delete function. If
4416 it is, then it will be the usual deallocation function. */
4417 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4418 if (second_parm == void_list_node)
4420 /* Do not consider this function if its second argument is an
4424 /* Otherwise, if we have a two-argument function and the second
4425 argument is `size_t', it will be the usual deallocation
4426 function -- unless there is one-argument function, too. */
4427 if (TREE_CHAIN (second_parm) == void_list_node
4428 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4429 has_two_argument_delete_p = true;
4432 return has_two_argument_delete_p;
4435 /* Check the validity of the bases and members declared in T. Add any
4436 implicitly-generated functions (like copy-constructors and
4437 assignment operators). Compute various flag bits (like
4438 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4439 level: i.e., independently of the ABI in use. */
4442 check_bases_and_members (tree t)
4444 /* Nonzero if the implicitly generated copy constructor should take
4445 a non-const reference argument. */
4446 int cant_have_const_ctor;
4447 /* Nonzero if the implicitly generated assignment operator
4448 should take a non-const reference argument. */
4449 int no_const_asn_ref;
4451 bool saved_complex_asn_ref;
4452 bool saved_nontrivial_dtor;
4455 /* By default, we use const reference arguments and generate default
4457 cant_have_const_ctor = 0;
4458 no_const_asn_ref = 0;
4460 /* Check all the base-classes. */
4461 check_bases (t, &cant_have_const_ctor,
4464 /* Check all the method declarations. */
4467 /* Save the initial values of these flags which only indicate whether
4468 or not the class has user-provided functions. As we analyze the
4469 bases and members we can set these flags for other reasons. */
4470 saved_complex_asn_ref = TYPE_HAS_COMPLEX_COPY_ASSIGN (t);
4471 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4473 /* Check all the data member declarations. We cannot call
4474 check_field_decls until we have called check_bases check_methods,
4475 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4476 being set appropriately. */
4477 check_field_decls (t, &access_decls,
4478 &cant_have_const_ctor,
4481 /* A nearly-empty class has to be vptr-containing; a nearly empty
4482 class contains just a vptr. */
4483 if (!TYPE_CONTAINS_VPTR_P (t))
4484 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4486 /* Do some bookkeeping that will guide the generation of implicitly
4487 declared member functions. */
4488 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4489 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4490 /* We need to call a constructor for this class if it has a
4491 user-provided constructor, or if the default constructor is going
4492 to initialize the vptr. (This is not an if-and-only-if;
4493 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4494 themselves need constructing.) */
4495 TYPE_NEEDS_CONSTRUCTING (t)
4496 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4499 An aggregate is an array or a class with no user-provided
4500 constructors ... and no virtual functions.
4502 Again, other conditions for being an aggregate are checked
4504 CLASSTYPE_NON_AGGREGATE (t)
4505 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4506 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4507 retain the old definition internally for ABI reasons. */
4508 CLASSTYPE_NON_LAYOUT_POD_P (t)
4509 |= (CLASSTYPE_NON_AGGREGATE (t)
4510 || saved_nontrivial_dtor || saved_complex_asn_ref);
4511 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
4512 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4513 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4514 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4516 /* If the class has no user-declared constructor, but does have
4517 non-static const or reference data members that can never be
4518 initialized, issue a warning. */
4519 if (warn_uninitialized
4520 /* Classes with user-declared constructors are presumed to
4521 initialize these members. */
4522 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4523 /* Aggregates can be initialized with brace-enclosed
4525 && CLASSTYPE_NON_AGGREGATE (t))
4529 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4533 if (TREE_CODE (field) != FIELD_DECL)
4536 type = TREE_TYPE (field);
4537 if (TREE_CODE (type) == REFERENCE_TYPE)
4538 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4539 "in class without a constructor", field);
4540 else if (CP_TYPE_CONST_P (type)
4541 && (!CLASS_TYPE_P (type)
4542 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4543 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4544 "in class without a constructor", field);
4548 /* Synthesize any needed methods. */
4549 add_implicitly_declared_members (t,
4550 cant_have_const_ctor,
4553 /* Check defaulted declarations here so we have cant_have_const_ctor
4554 and don't need to worry about clones. */
4555 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4556 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4558 int copy = copy_fn_p (fn);
4562 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
4563 : !no_const_asn_ref);
4564 bool fn_const_p = (copy == 2);
4566 if (fn_const_p && !imp_const_p)
4567 /* If the function is defaulted outside the class, we just
4568 give the synthesis error. */
4569 error ("%q+D declared to take const reference, but implicit "
4570 "declaration would take non-const", fn);
4571 else if (imp_const_p && !fn_const_p)
4572 error ("%q+D declared to take non-const reference cannot be "
4573 "defaulted in the class body", fn);
4575 defaulted_late_check (fn);
4578 if (LAMBDA_TYPE_P (t))
4580 /* "The closure type associated with a lambda-expression has a deleted
4581 default constructor and a deleted copy assignment operator." */
4582 TYPE_NEEDS_CONSTRUCTING (t) = 1;
4583 TYPE_HAS_COMPLEX_DFLT (t) = 1;
4584 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
4585 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 0;
4587 /* "This class type is not an aggregate." */
4588 CLASSTYPE_NON_AGGREGATE (t) = 1;
4591 /* Create the in-charge and not-in-charge variants of constructors
4593 clone_constructors_and_destructors (t);
4595 /* Process the using-declarations. */
4596 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4597 handle_using_decl (TREE_VALUE (access_decls), t);
4599 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4600 finish_struct_methods (t);
4602 /* Figure out whether or not we will need a cookie when dynamically
4603 allocating an array of this type. */
4604 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4605 = type_requires_array_cookie (t);
4608 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4609 accordingly. If a new vfield was created (because T doesn't have a
4610 primary base class), then the newly created field is returned. It
4611 is not added to the TYPE_FIELDS list; it is the caller's
4612 responsibility to do that. Accumulate declared virtual functions
4616 create_vtable_ptr (tree t, tree* virtuals_p)
4620 /* Collect the virtual functions declared in T. */
4621 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4622 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4623 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4625 tree new_virtual = make_node (TREE_LIST);
4627 BV_FN (new_virtual) = fn;
4628 BV_DELTA (new_virtual) = integer_zero_node;
4629 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4631 TREE_CHAIN (new_virtual) = *virtuals_p;
4632 *virtuals_p = new_virtual;
4635 /* If we couldn't find an appropriate base class, create a new field
4636 here. Even if there weren't any new virtual functions, we might need a
4637 new virtual function table if we're supposed to include vptrs in
4638 all classes that need them. */
4639 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4641 /* We build this decl with vtbl_ptr_type_node, which is a
4642 `vtable_entry_type*'. It might seem more precise to use
4643 `vtable_entry_type (*)[N]' where N is the number of virtual
4644 functions. However, that would require the vtable pointer in
4645 base classes to have a different type than the vtable pointer
4646 in derived classes. We could make that happen, but that
4647 still wouldn't solve all the problems. In particular, the
4648 type-based alias analysis code would decide that assignments
4649 to the base class vtable pointer can't alias assignments to
4650 the derived class vtable pointer, since they have different
4651 types. Thus, in a derived class destructor, where the base
4652 class constructor was inlined, we could generate bad code for
4653 setting up the vtable pointer.
4655 Therefore, we use one type for all vtable pointers. We still
4656 use a type-correct type; it's just doesn't indicate the array
4657 bounds. That's better than using `void*' or some such; it's
4658 cleaner, and it let's the alias analysis code know that these
4659 stores cannot alias stores to void*! */
4662 field = build_decl (input_location,
4663 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4664 DECL_VIRTUAL_P (field) = 1;
4665 DECL_ARTIFICIAL (field) = 1;
4666 DECL_FIELD_CONTEXT (field) = t;
4667 DECL_FCONTEXT (field) = t;
4668 if (TYPE_PACKED (t))
4669 DECL_PACKED (field) = 1;
4671 TYPE_VFIELD (t) = field;
4673 /* This class is non-empty. */
4674 CLASSTYPE_EMPTY_P (t) = 0;
4682 /* Add OFFSET to all base types of BINFO which is a base in the
4683 hierarchy dominated by T.
4685 OFFSET, which is a type offset, is number of bytes. */
4688 propagate_binfo_offsets (tree binfo, tree offset)
4694 /* Update BINFO's offset. */
4695 BINFO_OFFSET (binfo)
4696 = convert (sizetype,
4697 size_binop (PLUS_EXPR,
4698 convert (ssizetype, BINFO_OFFSET (binfo)),
4701 /* Find the primary base class. */
4702 primary_binfo = get_primary_binfo (binfo);
4704 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4705 propagate_binfo_offsets (primary_binfo, offset);
4707 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4709 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4711 /* Don't do the primary base twice. */
4712 if (base_binfo == primary_binfo)
4715 if (BINFO_VIRTUAL_P (base_binfo))
4718 propagate_binfo_offsets (base_binfo, offset);
4722 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4723 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4724 empty subobjects of T. */
4727 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4731 bool first_vbase = true;
4734 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4737 if (!abi_version_at_least(2))
4739 /* In G++ 3.2, we incorrectly rounded the size before laying out
4740 the virtual bases. */
4741 finish_record_layout (rli, /*free_p=*/false);
4742 #ifdef STRUCTURE_SIZE_BOUNDARY
4743 /* Packed structures don't need to have minimum size. */
4744 if (! TYPE_PACKED (t))
4745 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4747 rli->offset = TYPE_SIZE_UNIT (t);
4748 rli->bitpos = bitsize_zero_node;
4749 rli->record_align = TYPE_ALIGN (t);
4752 /* Find the last field. The artificial fields created for virtual
4753 bases will go after the last extant field to date. */
4754 next_field = &TYPE_FIELDS (t);
4756 next_field = &TREE_CHAIN (*next_field);
4758 /* Go through the virtual bases, allocating space for each virtual
4759 base that is not already a primary base class. These are
4760 allocated in inheritance graph order. */
4761 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4763 if (!BINFO_VIRTUAL_P (vbase))
4766 if (!BINFO_PRIMARY_P (vbase))
4768 tree basetype = TREE_TYPE (vbase);
4770 /* This virtual base is not a primary base of any class in the
4771 hierarchy, so we have to add space for it. */
4772 next_field = build_base_field (rli, vbase,
4773 offsets, next_field);
4775 /* If the first virtual base might have been placed at a
4776 lower address, had we started from CLASSTYPE_SIZE, rather
4777 than TYPE_SIZE, issue a warning. There can be both false
4778 positives and false negatives from this warning in rare
4779 cases; to deal with all the possibilities would probably
4780 require performing both layout algorithms and comparing
4781 the results which is not particularly tractable. */
4785 (size_binop (CEIL_DIV_EXPR,
4786 round_up_loc (input_location,
4788 CLASSTYPE_ALIGN (basetype)),
4790 BINFO_OFFSET (vbase))))
4792 "offset of virtual base %qT is not ABI-compliant and "
4793 "may change in a future version of GCC",
4796 first_vbase = false;
4801 /* Returns the offset of the byte just past the end of the base class
4805 end_of_base (tree binfo)
4809 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
4810 size = TYPE_SIZE_UNIT (char_type_node);
4811 else if (is_empty_class (BINFO_TYPE (binfo)))
4812 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4813 allocate some space for it. It cannot have virtual bases, so
4814 TYPE_SIZE_UNIT is fine. */
4815 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4817 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4819 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4822 /* Returns the offset of the byte just past the end of the base class
4823 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4824 only non-virtual bases are included. */
4827 end_of_class (tree t, int include_virtuals_p)
4829 tree result = size_zero_node;
4830 VEC(tree,gc) *vbases;
4836 for (binfo = TYPE_BINFO (t), i = 0;
4837 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4839 if (!include_virtuals_p
4840 && BINFO_VIRTUAL_P (base_binfo)
4841 && (!BINFO_PRIMARY_P (base_binfo)
4842 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4845 offset = end_of_base (base_binfo);
4846 if (INT_CST_LT_UNSIGNED (result, offset))
4850 /* G++ 3.2 did not check indirect virtual bases. */
4851 if (abi_version_at_least (2) && include_virtuals_p)
4852 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4853 VEC_iterate (tree, vbases, i, base_binfo); i++)
4855 offset = end_of_base (base_binfo);
4856 if (INT_CST_LT_UNSIGNED (result, offset))
4863 /* Warn about bases of T that are inaccessible because they are
4864 ambiguous. For example:
4867 struct T : public S {};
4868 struct U : public S, public T {};
4870 Here, `(S*) new U' is not allowed because there are two `S'
4874 warn_about_ambiguous_bases (tree t)
4877 VEC(tree,gc) *vbases;
4882 /* If there are no repeated bases, nothing can be ambiguous. */
4883 if (!CLASSTYPE_REPEATED_BASE_P (t))
4886 /* Check direct bases. */
4887 for (binfo = TYPE_BINFO (t), i = 0;
4888 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4890 basetype = BINFO_TYPE (base_binfo);
4892 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4893 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4897 /* Check for ambiguous virtual bases. */
4899 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4900 VEC_iterate (tree, vbases, i, binfo); i++)
4902 basetype = BINFO_TYPE (binfo);
4904 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4905 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4910 /* Compare two INTEGER_CSTs K1 and K2. */
4913 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4915 return tree_int_cst_compare ((tree) k1, (tree) k2);
4918 /* Increase the size indicated in RLI to account for empty classes
4919 that are "off the end" of the class. */
4922 include_empty_classes (record_layout_info rli)
4927 /* It might be the case that we grew the class to allocate a
4928 zero-sized base class. That won't be reflected in RLI, yet,
4929 because we are willing to overlay multiple bases at the same
4930 offset. However, now we need to make sure that RLI is big enough
4931 to reflect the entire class. */
4932 eoc = end_of_class (rli->t,
4933 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4934 rli_size = rli_size_unit_so_far (rli);
4935 if (TREE_CODE (rli_size) == INTEGER_CST
4936 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4938 if (!abi_version_at_least (2))
4939 /* In version 1 of the ABI, the size of a class that ends with
4940 a bitfield was not rounded up to a whole multiple of a
4941 byte. Because rli_size_unit_so_far returns only the number
4942 of fully allocated bytes, any extra bits were not included
4944 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4946 /* The size should have been rounded to a whole byte. */
4947 gcc_assert (tree_int_cst_equal
4948 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4950 = size_binop (PLUS_EXPR,
4952 size_binop (MULT_EXPR,
4953 convert (bitsizetype,
4954 size_binop (MINUS_EXPR,
4956 bitsize_int (BITS_PER_UNIT)));
4957 normalize_rli (rli);
4961 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4962 BINFO_OFFSETs for all of the base-classes. Position the vtable
4963 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4966 layout_class_type (tree t, tree *virtuals_p)
4968 tree non_static_data_members;
4971 record_layout_info rli;
4972 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4973 types that appear at that offset. */
4974 splay_tree empty_base_offsets;
4975 /* True if the last field layed out was a bit-field. */
4976 bool last_field_was_bitfield = false;
4977 /* The location at which the next field should be inserted. */
4979 /* T, as a base class. */
4982 /* Keep track of the first non-static data member. */
4983 non_static_data_members = TYPE_FIELDS (t);
4985 /* Start laying out the record. */
4986 rli = start_record_layout (t);
4988 /* Mark all the primary bases in the hierarchy. */
4989 determine_primary_bases (t);
4991 /* Create a pointer to our virtual function table. */
4992 vptr = create_vtable_ptr (t, virtuals_p);
4994 /* The vptr is always the first thing in the class. */
4997 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4998 TYPE_FIELDS (t) = vptr;
4999 next_field = &TREE_CHAIN (vptr);
5000 place_field (rli, vptr);
5003 next_field = &TYPE_FIELDS (t);
5005 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5006 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
5008 build_base_fields (rli, empty_base_offsets, next_field);
5010 /* Layout the non-static data members. */
5011 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
5016 /* We still pass things that aren't non-static data members to
5017 the back end, in case it wants to do something with them. */
5018 if (TREE_CODE (field) != FIELD_DECL)
5020 place_field (rli, field);
5021 /* If the static data member has incomplete type, keep track
5022 of it so that it can be completed later. (The handling
5023 of pending statics in finish_record_layout is
5024 insufficient; consider:
5027 struct S2 { static S1 s1; };
5029 At this point, finish_record_layout will be called, but
5030 S1 is still incomplete.) */
5031 if (TREE_CODE (field) == VAR_DECL)
5033 maybe_register_incomplete_var (field);
5034 /* The visibility of static data members is determined
5035 at their point of declaration, not their point of
5037 determine_visibility (field);
5042 type = TREE_TYPE (field);
5043 if (type == error_mark_node)
5046 padding = NULL_TREE;
5048 /* If this field is a bit-field whose width is greater than its
5049 type, then there are some special rules for allocating
5051 if (DECL_C_BIT_FIELD (field)
5052 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
5056 bool was_unnamed_p = false;
5057 /* We must allocate the bits as if suitably aligned for the
5058 longest integer type that fits in this many bits. type
5059 of the field. Then, we are supposed to use the left over
5060 bits as additional padding. */
5061 for (itk = itk_char; itk != itk_none; ++itk)
5062 if (integer_types[itk] != NULL_TREE
5063 && (INT_CST_LT (size_int (MAX_FIXED_MODE_SIZE),
5064 TYPE_SIZE (integer_types[itk]))
5065 || INT_CST_LT (DECL_SIZE (field),
5066 TYPE_SIZE (integer_types[itk]))))
5069 /* ITK now indicates a type that is too large for the
5070 field. We have to back up by one to find the largest
5075 integer_type = integer_types[itk];
5076 } while (itk > 0 && integer_type == NULL_TREE);
5078 /* Figure out how much additional padding is required. GCC
5079 3.2 always created a padding field, even if it had zero
5081 if (!abi_version_at_least (2)
5082 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
5084 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
5085 /* In a union, the padding field must have the full width
5086 of the bit-field; all fields start at offset zero. */
5087 padding = DECL_SIZE (field);
5090 if (TREE_CODE (t) == UNION_TYPE)
5091 warning (OPT_Wabi, "size assigned to %qT may not be "
5092 "ABI-compliant and may change in a future "
5095 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
5096 TYPE_SIZE (integer_type));
5099 #ifdef PCC_BITFIELD_TYPE_MATTERS
5100 /* An unnamed bitfield does not normally affect the
5101 alignment of the containing class on a target where
5102 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5103 make any exceptions for unnamed bitfields when the
5104 bitfields are longer than their types. Therefore, we
5105 temporarily give the field a name. */
5106 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
5108 was_unnamed_p = true;
5109 DECL_NAME (field) = make_anon_name ();
5112 DECL_SIZE (field) = TYPE_SIZE (integer_type);
5113 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
5114 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
5115 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5116 empty_base_offsets);
5118 DECL_NAME (field) = NULL_TREE;
5119 /* Now that layout has been performed, set the size of the
5120 field to the size of its declared type; the rest of the
5121 field is effectively invisible. */
5122 DECL_SIZE (field) = TYPE_SIZE (type);
5123 /* We must also reset the DECL_MODE of the field. */
5124 if (abi_version_at_least (2))
5125 DECL_MODE (field) = TYPE_MODE (type);
5127 && DECL_MODE (field) != TYPE_MODE (type))
5128 /* Versions of G++ before G++ 3.4 did not reset the
5131 "the offset of %qD may not be ABI-compliant and may "
5132 "change in a future version of GCC", field);
5135 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5136 empty_base_offsets);
5138 /* Remember the location of any empty classes in FIELD. */
5139 if (abi_version_at_least (2))
5140 record_subobject_offsets (TREE_TYPE (field),
5141 byte_position(field),
5143 /*is_data_member=*/true);
5145 /* If a bit-field does not immediately follow another bit-field,
5146 and yet it starts in the middle of a byte, we have failed to
5147 comply with the ABI. */
5149 && DECL_C_BIT_FIELD (field)
5150 /* The TREE_NO_WARNING flag gets set by Objective-C when
5151 laying out an Objective-C class. The ObjC ABI differs
5152 from the C++ ABI, and so we do not want a warning
5154 && !TREE_NO_WARNING (field)
5155 && !last_field_was_bitfield
5156 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5157 DECL_FIELD_BIT_OFFSET (field),
5158 bitsize_unit_node)))
5159 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5160 "change in a future version of GCC", field);
5162 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5163 offset of the field. */
5165 && !abi_version_at_least (2)
5166 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5167 byte_position (field))
5168 && contains_empty_class_p (TREE_TYPE (field)))
5169 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5170 "classes to be placed at different locations in a "
5171 "future version of GCC", field);
5173 /* The middle end uses the type of expressions to determine the
5174 possible range of expression values. In order to optimize
5175 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5176 must be made aware of the width of "i", via its type.
5178 Because C++ does not have integer types of arbitrary width,
5179 we must (for the purposes of the front end) convert from the
5180 type assigned here to the declared type of the bitfield
5181 whenever a bitfield expression is used as an rvalue.
5182 Similarly, when assigning a value to a bitfield, the value
5183 must be converted to the type given the bitfield here. */
5184 if (DECL_C_BIT_FIELD (field))
5186 unsigned HOST_WIDE_INT width;
5187 tree ftype = TREE_TYPE (field);
5188 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5189 if (width != TYPE_PRECISION (ftype))
5192 = c_build_bitfield_integer_type (width,
5193 TYPE_UNSIGNED (ftype));
5195 = cp_build_qualified_type (TREE_TYPE (field),
5196 cp_type_quals (ftype));
5200 /* If we needed additional padding after this field, add it
5206 padding_field = build_decl (input_location,
5210 DECL_BIT_FIELD (padding_field) = 1;
5211 DECL_SIZE (padding_field) = padding;
5212 DECL_CONTEXT (padding_field) = t;
5213 DECL_ARTIFICIAL (padding_field) = 1;
5214 DECL_IGNORED_P (padding_field) = 1;
5215 layout_nonempty_base_or_field (rli, padding_field,
5217 empty_base_offsets);
5220 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5223 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5225 /* Make sure that we are on a byte boundary so that the size of
5226 the class without virtual bases will always be a round number
5228 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5229 normalize_rli (rli);
5232 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5234 if (!abi_version_at_least (2))
5235 include_empty_classes(rli);
5237 /* Delete all zero-width bit-fields from the list of fields. Now
5238 that the type is laid out they are no longer important. */
5239 remove_zero_width_bit_fields (t);
5241 /* Create the version of T used for virtual bases. We do not use
5242 make_class_type for this version; this is an artificial type. For
5243 a POD type, we just reuse T. */
5244 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5246 base_t = make_node (TREE_CODE (t));
5248 /* Set the size and alignment for the new type. In G++ 3.2, all
5249 empty classes were considered to have size zero when used as
5251 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5253 TYPE_SIZE (base_t) = bitsize_zero_node;
5254 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5255 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5257 "layout of classes derived from empty class %qT "
5258 "may change in a future version of GCC",
5265 /* If the ABI version is not at least two, and the last
5266 field was a bit-field, RLI may not be on a byte
5267 boundary. In particular, rli_size_unit_so_far might
5268 indicate the last complete byte, while rli_size_so_far
5269 indicates the total number of bits used. Therefore,
5270 rli_size_so_far, rather than rli_size_unit_so_far, is
5271 used to compute TYPE_SIZE_UNIT. */
5272 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5273 TYPE_SIZE_UNIT (base_t)
5274 = size_binop (MAX_EXPR,
5276 size_binop (CEIL_DIV_EXPR,
5277 rli_size_so_far (rli),
5278 bitsize_int (BITS_PER_UNIT))),
5281 = size_binop (MAX_EXPR,
5282 rli_size_so_far (rli),
5283 size_binop (MULT_EXPR,
5284 convert (bitsizetype, eoc),
5285 bitsize_int (BITS_PER_UNIT)));
5287 TYPE_ALIGN (base_t) = rli->record_align;
5288 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5290 /* Copy the fields from T. */
5291 next_field = &TYPE_FIELDS (base_t);
5292 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5293 if (TREE_CODE (field) == FIELD_DECL)
5295 *next_field = build_decl (input_location,
5299 DECL_CONTEXT (*next_field) = base_t;
5300 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5301 DECL_FIELD_BIT_OFFSET (*next_field)
5302 = DECL_FIELD_BIT_OFFSET (field);
5303 DECL_SIZE (*next_field) = DECL_SIZE (field);
5304 DECL_MODE (*next_field) = DECL_MODE (field);
5305 next_field = &TREE_CHAIN (*next_field);
5308 /* Record the base version of the type. */
5309 CLASSTYPE_AS_BASE (t) = base_t;
5310 TYPE_CONTEXT (base_t) = t;
5313 CLASSTYPE_AS_BASE (t) = t;
5315 /* Every empty class contains an empty class. */
5316 if (CLASSTYPE_EMPTY_P (t))
5317 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5319 /* Set the TYPE_DECL for this type to contain the right
5320 value for DECL_OFFSET, so that we can use it as part
5321 of a COMPONENT_REF for multiple inheritance. */
5322 layout_decl (TYPE_MAIN_DECL (t), 0);
5324 /* Now fix up any virtual base class types that we left lying
5325 around. We must get these done before we try to lay out the
5326 virtual function table. As a side-effect, this will remove the
5327 base subobject fields. */
5328 layout_virtual_bases (rli, empty_base_offsets);
5330 /* Make sure that empty classes are reflected in RLI at this
5332 include_empty_classes(rli);
5334 /* Make sure not to create any structures with zero size. */
5335 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5337 build_decl (input_location,
5338 FIELD_DECL, NULL_TREE, char_type_node));
5340 /* If this is a non-POD, declaring it packed makes a difference to how it
5341 can be used as a field; don't let finalize_record_size undo it. */
5342 if (TYPE_PACKED (t) && !layout_pod_type_p (t))
5343 rli->packed_maybe_necessary = true;
5345 /* Let the back end lay out the type. */
5346 finish_record_layout (rli, /*free_p=*/true);
5348 /* Warn about bases that can't be talked about due to ambiguity. */
5349 warn_about_ambiguous_bases (t);
5351 /* Now that we're done with layout, give the base fields the real types. */
5352 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5353 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5354 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5357 splay_tree_delete (empty_base_offsets);
5359 if (CLASSTYPE_EMPTY_P (t)
5360 && tree_int_cst_lt (sizeof_biggest_empty_class,
5361 TYPE_SIZE_UNIT (t)))
5362 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5365 /* Determine the "key method" for the class type indicated by TYPE,
5366 and set CLASSTYPE_KEY_METHOD accordingly. */
5369 determine_key_method (tree type)
5373 if (TYPE_FOR_JAVA (type)
5374 || processing_template_decl
5375 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5376 || CLASSTYPE_INTERFACE_KNOWN (type))
5379 /* The key method is the first non-pure virtual function that is not
5380 inline at the point of class definition. On some targets the
5381 key function may not be inline; those targets should not call
5382 this function until the end of the translation unit. */
5383 for (method = TYPE_METHODS (type); method != NULL_TREE;
5384 method = TREE_CHAIN (method))
5385 if (DECL_VINDEX (method) != NULL_TREE
5386 && ! DECL_DECLARED_INLINE_P (method)
5387 && ! DECL_PURE_VIRTUAL_P (method))
5389 CLASSTYPE_KEY_METHOD (type) = method;
5396 /* Perform processing required when the definition of T (a class type)
5400 finish_struct_1 (tree t)
5403 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5404 tree virtuals = NULL_TREE;
5407 if (COMPLETE_TYPE_P (t))
5409 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5410 error ("redefinition of %q#T", t);
5415 /* If this type was previously laid out as a forward reference,
5416 make sure we lay it out again. */
5417 TYPE_SIZE (t) = NULL_TREE;
5418 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5420 /* Make assumptions about the class; we'll reset the flags if
5422 CLASSTYPE_EMPTY_P (t) = 1;
5423 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5424 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5426 /* Do end-of-class semantic processing: checking the validity of the
5427 bases and members and add implicitly generated methods. */
5428 check_bases_and_members (t);
5430 /* Find the key method. */
5431 if (TYPE_CONTAINS_VPTR_P (t))
5433 /* The Itanium C++ ABI permits the key method to be chosen when
5434 the class is defined -- even though the key method so
5435 selected may later turn out to be an inline function. On
5436 some systems (such as ARM Symbian OS) the key method cannot
5437 be determined until the end of the translation unit. On such
5438 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5439 will cause the class to be added to KEYED_CLASSES. Then, in
5440 finish_file we will determine the key method. */
5441 if (targetm.cxx.key_method_may_be_inline ())
5442 determine_key_method (t);
5444 /* If a polymorphic class has no key method, we may emit the vtable
5445 in every translation unit where the class definition appears. */
5446 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5447 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5450 /* Layout the class itself. */
5451 layout_class_type (t, &virtuals);
5452 if (CLASSTYPE_AS_BASE (t) != t)
5453 /* We use the base type for trivial assignments, and hence it
5455 compute_record_mode (CLASSTYPE_AS_BASE (t));
5457 virtuals = modify_all_vtables (t, nreverse (virtuals));
5459 /* If necessary, create the primary vtable for this class. */
5460 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5462 /* We must enter these virtuals into the table. */
5463 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5464 build_primary_vtable (NULL_TREE, t);
5465 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5466 /* Here we know enough to change the type of our virtual
5467 function table, but we will wait until later this function. */
5468 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5471 if (TYPE_CONTAINS_VPTR_P (t))
5476 if (BINFO_VTABLE (TYPE_BINFO (t)))
5477 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5478 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5479 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5481 /* Add entries for virtual functions introduced by this class. */
5482 BINFO_VIRTUALS (TYPE_BINFO (t))
5483 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5485 /* Set DECL_VINDEX for all functions declared in this class. */
5486 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5488 fn = TREE_CHAIN (fn),
5489 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5490 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5492 tree fndecl = BV_FN (fn);
5494 if (DECL_THUNK_P (fndecl))
5495 /* A thunk. We should never be calling this entry directly
5496 from this vtable -- we'd use the entry for the non
5497 thunk base function. */
5498 DECL_VINDEX (fndecl) = NULL_TREE;
5499 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5500 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5504 finish_struct_bits (t);
5506 /* Complete the rtl for any static member objects of the type we're
5508 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5509 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5510 && TREE_TYPE (x) != error_mark_node
5511 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5512 DECL_MODE (x) = TYPE_MODE (t);
5514 /* Done with FIELDS...now decide whether to sort these for
5515 faster lookups later.
5517 We use a small number because most searches fail (succeeding
5518 ultimately as the search bores through the inheritance
5519 hierarchy), and we want this failure to occur quickly. */
5521 n_fields = count_fields (TYPE_FIELDS (t));
5524 struct sorted_fields_type *field_vec = ggc_alloc_sorted_fields_type
5525 (sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5526 field_vec->len = n_fields;
5527 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5528 qsort (field_vec->elts, n_fields, sizeof (tree),
5530 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
5533 /* Complain if one of the field types requires lower visibility. */
5534 constrain_class_visibility (t);
5536 /* Make the rtl for any new vtables we have created, and unmark
5537 the base types we marked. */
5540 /* Build the VTT for T. */
5543 /* This warning does not make sense for Java classes, since they
5544 cannot have destructors. */
5545 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5549 dtor = CLASSTYPE_DESTRUCTORS (t);
5550 if (/* An implicitly declared destructor is always public. And,
5551 if it were virtual, we would have created it by now. */
5553 || (!DECL_VINDEX (dtor)
5554 && (/* public non-virtual */
5555 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5556 || (/* non-public non-virtual with friends */
5557 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5558 && (CLASSTYPE_FRIEND_CLASSES (t)
5559 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5560 warning (OPT_Wnon_virtual_dtor,
5561 "%q#T has virtual functions and accessible"
5562 " non-virtual destructor", t);
5567 if (warn_overloaded_virtual)
5570 /* Class layout, assignment of virtual table slots, etc., is now
5571 complete. Give the back end a chance to tweak the visibility of
5572 the class or perform any other required target modifications. */
5573 targetm.cxx.adjust_class_at_definition (t);
5575 maybe_suppress_debug_info (t);
5577 dump_class_hierarchy (t);
5579 /* Finish debugging output for this type. */
5580 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5583 /* When T was built up, the member declarations were added in reverse
5584 order. Rearrange them to declaration order. */
5587 unreverse_member_declarations (tree t)
5593 /* The following lists are all in reverse order. Put them in
5594 declaration order now. */
5595 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5596 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5598 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5599 reverse order, so we can't just use nreverse. */
5601 for (x = TYPE_FIELDS (t);
5602 x && TREE_CODE (x) != TYPE_DECL;
5605 next = TREE_CHAIN (x);
5606 TREE_CHAIN (x) = prev;
5611 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5613 TYPE_FIELDS (t) = prev;
5618 finish_struct (tree t, tree attributes)
5620 location_t saved_loc = input_location;
5622 /* Now that we've got all the field declarations, reverse everything
5624 unreverse_member_declarations (t);
5626 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5628 /* Nadger the current location so that diagnostics point to the start of
5629 the struct, not the end. */
5630 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5632 if (processing_template_decl)
5636 finish_struct_methods (t);
5637 TYPE_SIZE (t) = bitsize_zero_node;
5638 TYPE_SIZE_UNIT (t) = size_zero_node;
5640 /* We need to emit an error message if this type was used as a parameter
5641 and it is an abstract type, even if it is a template. We construct
5642 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5643 account and we call complete_vars with this type, which will check
5644 the PARM_DECLS. Note that while the type is being defined,
5645 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5646 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5647 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5648 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5649 if (DECL_PURE_VIRTUAL_P (x))
5650 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5653 /* Remember current #pragma pack value. */
5654 TYPE_PRECISION (t) = maximum_field_alignment;
5657 finish_struct_1 (t);
5659 input_location = saved_loc;
5661 TYPE_BEING_DEFINED (t) = 0;
5663 if (current_class_type)
5666 error ("trying to finish struct, but kicked out due to previous parse errors");
5668 if (processing_template_decl && at_function_scope_p ())
5669 add_stmt (build_min (TAG_DEFN, t));
5674 /* Return the dynamic type of INSTANCE, if known.
5675 Used to determine whether the virtual function table is needed
5678 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5679 of our knowledge of its type. *NONNULL should be initialized
5680 before this function is called. */
5683 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5685 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5687 switch (TREE_CODE (instance))
5690 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5693 return RECUR (TREE_OPERAND (instance, 0));
5696 /* This is a call to a constructor, hence it's never zero. */
5697 if (TREE_HAS_CONSTRUCTOR (instance))
5701 return TREE_TYPE (instance);
5706 /* This is a call to a constructor, hence it's never zero. */
5707 if (TREE_HAS_CONSTRUCTOR (instance))
5711 return TREE_TYPE (instance);
5713 return RECUR (TREE_OPERAND (instance, 0));
5715 case POINTER_PLUS_EXPR:
5718 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5719 return RECUR (TREE_OPERAND (instance, 0));
5720 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5721 /* Propagate nonnull. */
5722 return RECUR (TREE_OPERAND (instance, 0));
5727 return RECUR (TREE_OPERAND (instance, 0));
5730 instance = TREE_OPERAND (instance, 0);
5733 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5734 with a real object -- given &p->f, p can still be null. */
5735 tree t = get_base_address (instance);
5736 /* ??? Probably should check DECL_WEAK here. */
5737 if (t && DECL_P (t))
5740 return RECUR (instance);
5743 /* If this component is really a base class reference, then the field
5744 itself isn't definitive. */
5745 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5746 return RECUR (TREE_OPERAND (instance, 0));
5747 return RECUR (TREE_OPERAND (instance, 1));
5751 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5752 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
5756 return TREE_TYPE (TREE_TYPE (instance));
5758 /* fall through... */
5762 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
5766 return TREE_TYPE (instance);
5768 else if (instance == current_class_ptr)
5773 /* if we're in a ctor or dtor, we know our type. */
5774 if (DECL_LANG_SPECIFIC (current_function_decl)
5775 && (DECL_CONSTRUCTOR_P (current_function_decl)
5776 || DECL_DESTRUCTOR_P (current_function_decl)))
5780 return TREE_TYPE (TREE_TYPE (instance));
5783 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5785 /* We only need one hash table because it is always left empty. */
5788 ht = htab_create (37,
5793 /* Reference variables should be references to objects. */
5797 /* Enter the INSTANCE in a table to prevent recursion; a
5798 variable's initializer may refer to the variable
5800 if (TREE_CODE (instance) == VAR_DECL
5801 && DECL_INITIAL (instance)
5802 && !htab_find (ht, instance))
5807 slot = htab_find_slot (ht, instance, INSERT);
5809 type = RECUR (DECL_INITIAL (instance));
5810 htab_remove_elt (ht, instance);
5823 /* Return nonzero if the dynamic type of INSTANCE is known, and
5824 equivalent to the static type. We also handle the case where
5825 INSTANCE is really a pointer. Return negative if this is a
5826 ctor/dtor. There the dynamic type is known, but this might not be
5827 the most derived base of the original object, and hence virtual
5828 bases may not be layed out according to this type.
5830 Used to determine whether the virtual function table is needed
5833 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5834 of our knowledge of its type. *NONNULL should be initialized
5835 before this function is called. */
5838 resolves_to_fixed_type_p (tree instance, int* nonnull)
5840 tree t = TREE_TYPE (instance);
5842 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5843 if (fixed == NULL_TREE)
5845 if (POINTER_TYPE_P (t))
5847 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5849 return cdtorp ? -1 : 1;
5854 init_class_processing (void)
5856 current_class_depth = 0;
5857 current_class_stack_size = 10;
5859 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5860 local_classes = VEC_alloc (tree, gc, 8);
5861 sizeof_biggest_empty_class = size_zero_node;
5863 ridpointers[(int) RID_PUBLIC] = access_public_node;
5864 ridpointers[(int) RID_PRIVATE] = access_private_node;
5865 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5868 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5871 restore_class_cache (void)
5875 /* We are re-entering the same class we just left, so we don't
5876 have to search the whole inheritance matrix to find all the
5877 decls to bind again. Instead, we install the cached
5878 class_shadowed list and walk through it binding names. */
5879 push_binding_level (previous_class_level);
5880 class_binding_level = previous_class_level;
5881 /* Restore IDENTIFIER_TYPE_VALUE. */
5882 for (type = class_binding_level->type_shadowed;
5884 type = TREE_CHAIN (type))
5885 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5888 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5889 appropriate for TYPE.
5891 So that we may avoid calls to lookup_name, we cache the _TYPE
5892 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5894 For multiple inheritance, we perform a two-pass depth-first search
5895 of the type lattice. */
5898 pushclass (tree type)
5900 class_stack_node_t csn;
5902 type = TYPE_MAIN_VARIANT (type);
5904 /* Make sure there is enough room for the new entry on the stack. */
5905 if (current_class_depth + 1 >= current_class_stack_size)
5907 current_class_stack_size *= 2;
5909 = XRESIZEVEC (struct class_stack_node, current_class_stack,
5910 current_class_stack_size);
5913 /* Insert a new entry on the class stack. */
5914 csn = current_class_stack + current_class_depth;
5915 csn->name = current_class_name;
5916 csn->type = current_class_type;
5917 csn->access = current_access_specifier;
5918 csn->names_used = 0;
5920 current_class_depth++;
5922 /* Now set up the new type. */
5923 current_class_name = TYPE_NAME (type);
5924 if (TREE_CODE (current_class_name) == TYPE_DECL)
5925 current_class_name = DECL_NAME (current_class_name);
5926 current_class_type = type;
5928 /* By default, things in classes are private, while things in
5929 structures or unions are public. */
5930 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5931 ? access_private_node
5932 : access_public_node);
5934 if (previous_class_level
5935 && type != previous_class_level->this_entity
5936 && current_class_depth == 1)
5938 /* Forcibly remove any old class remnants. */
5939 invalidate_class_lookup_cache ();
5942 if (!previous_class_level
5943 || type != previous_class_level->this_entity
5944 || current_class_depth > 1)
5947 restore_class_cache ();
5950 /* When we exit a toplevel class scope, we save its binding level so
5951 that we can restore it quickly. Here, we've entered some other
5952 class, so we must invalidate our cache. */
5955 invalidate_class_lookup_cache (void)
5957 previous_class_level = NULL;
5960 /* Get out of the current class scope. If we were in a class scope
5961 previously, that is the one popped to. */
5968 current_class_depth--;
5969 current_class_name = current_class_stack[current_class_depth].name;
5970 current_class_type = current_class_stack[current_class_depth].type;
5971 current_access_specifier = current_class_stack[current_class_depth].access;
5972 if (current_class_stack[current_class_depth].names_used)
5973 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5976 /* Mark the top of the class stack as hidden. */
5979 push_class_stack (void)
5981 if (current_class_depth)
5982 ++current_class_stack[current_class_depth - 1].hidden;
5985 /* Mark the top of the class stack as un-hidden. */
5988 pop_class_stack (void)
5990 if (current_class_depth)
5991 --current_class_stack[current_class_depth - 1].hidden;
5994 /* Returns 1 if the class type currently being defined is either T or
5995 a nested type of T. */
5998 currently_open_class (tree t)
6002 if (!CLASS_TYPE_P (t))
6005 t = TYPE_MAIN_VARIANT (t);
6007 /* We start looking from 1 because entry 0 is from global scope,
6009 for (i = current_class_depth; i > 0; --i)
6012 if (i == current_class_depth)
6013 c = current_class_type;
6016 if (current_class_stack[i].hidden)
6018 c = current_class_stack[i].type;
6022 if (same_type_p (c, t))
6028 /* If either current_class_type or one of its enclosing classes are derived
6029 from T, return the appropriate type. Used to determine how we found
6030 something via unqualified lookup. */
6033 currently_open_derived_class (tree t)
6037 /* The bases of a dependent type are unknown. */
6038 if (dependent_type_p (t))
6041 if (!current_class_type)
6044 if (DERIVED_FROM_P (t, current_class_type))
6045 return current_class_type;
6047 for (i = current_class_depth - 1; i > 0; --i)
6049 if (current_class_stack[i].hidden)
6051 if (DERIVED_FROM_P (t, current_class_stack[i].type))
6052 return current_class_stack[i].type;
6058 /* Returns the innermost class type which is not a lambda closure type. */
6061 current_nonlambda_class_type (void)
6065 /* We start looking from 1 because entry 0 is from global scope,
6067 for (i = current_class_depth; i > 0; --i)
6070 if (i == current_class_depth)
6071 c = current_class_type;
6074 if (current_class_stack[i].hidden)
6076 c = current_class_stack[i].type;
6080 if (!LAMBDA_TYPE_P (c))
6086 /* When entering a class scope, all enclosing class scopes' names with
6087 static meaning (static variables, static functions, types and
6088 enumerators) have to be visible. This recursive function calls
6089 pushclass for all enclosing class contexts until global or a local
6090 scope is reached. TYPE is the enclosed class. */
6093 push_nested_class (tree type)
6095 /* A namespace might be passed in error cases, like A::B:C. */
6096 if (type == NULL_TREE
6097 || !CLASS_TYPE_P (type))
6100 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
6105 /* Undoes a push_nested_class call. */
6108 pop_nested_class (void)
6110 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
6113 if (context && CLASS_TYPE_P (context))
6114 pop_nested_class ();
6117 /* Returns the number of extern "LANG" blocks we are nested within. */
6120 current_lang_depth (void)
6122 return VEC_length (tree, current_lang_base);
6125 /* Set global variables CURRENT_LANG_NAME to appropriate value
6126 so that behavior of name-mangling machinery is correct. */
6129 push_lang_context (tree name)
6131 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
6133 if (name == lang_name_cplusplus)
6135 current_lang_name = name;
6137 else if (name == lang_name_java)
6139 current_lang_name = name;
6140 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6141 (See record_builtin_java_type in decl.c.) However, that causes
6142 incorrect debug entries if these types are actually used.
6143 So we re-enable debug output after extern "Java". */
6144 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
6145 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
6146 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
6147 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
6148 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
6149 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
6150 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
6151 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
6153 else if (name == lang_name_c)
6155 current_lang_name = name;
6158 error ("language string %<\"%E\"%> not recognized", name);
6161 /* Get out of the current language scope. */
6164 pop_lang_context (void)
6166 current_lang_name = VEC_pop (tree, current_lang_base);
6169 /* Type instantiation routines. */
6171 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6172 matches the TARGET_TYPE. If there is no satisfactory match, return
6173 error_mark_node, and issue an error & warning messages under
6174 control of FLAGS. Permit pointers to member function if FLAGS
6175 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6176 a template-id, and EXPLICIT_TARGS are the explicitly provided
6179 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6180 is the base path used to reference those member functions. If
6181 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6182 resolved to a member function, access checks will be performed and
6183 errors issued if appropriate. */
6186 resolve_address_of_overloaded_function (tree target_type,
6188 tsubst_flags_t flags,
6190 tree explicit_targs,
6193 /* Here's what the standard says:
6197 If the name is a function template, template argument deduction
6198 is done, and if the argument deduction succeeds, the deduced
6199 arguments are used to generate a single template function, which
6200 is added to the set of overloaded functions considered.
6202 Non-member functions and static member functions match targets of
6203 type "pointer-to-function" or "reference-to-function." Nonstatic
6204 member functions match targets of type "pointer-to-member
6205 function;" the function type of the pointer to member is used to
6206 select the member function from the set of overloaded member
6207 functions. If a nonstatic member function is selected, the
6208 reference to the overloaded function name is required to have the
6209 form of a pointer to member as described in 5.3.1.
6211 If more than one function is selected, any template functions in
6212 the set are eliminated if the set also contains a non-template
6213 function, and any given template function is eliminated if the
6214 set contains a second template function that is more specialized
6215 than the first according to the partial ordering rules 14.5.5.2.
6216 After such eliminations, if any, there shall remain exactly one
6217 selected function. */
6220 /* We store the matches in a TREE_LIST rooted here. The functions
6221 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6222 interoperability with most_specialized_instantiation. */
6223 tree matches = NULL_TREE;
6225 tree target_fn_type;
6227 /* By the time we get here, we should be seeing only real
6228 pointer-to-member types, not the internal POINTER_TYPE to
6229 METHOD_TYPE representation. */
6230 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6231 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6233 gcc_assert (is_overloaded_fn (overload));
6235 /* Check that the TARGET_TYPE is reasonable. */
6236 if (TYPE_PTRFN_P (target_type))
6238 else if (TYPE_PTRMEMFUNC_P (target_type))
6239 /* This is OK, too. */
6241 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6242 /* This is OK, too. This comes from a conversion to reference
6244 target_type = build_reference_type (target_type);
6247 if (flags & tf_error)
6248 error ("cannot resolve overloaded function %qD based on"
6249 " conversion to type %qT",
6250 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6251 return error_mark_node;
6254 /* Non-member functions and static member functions match targets of type
6255 "pointer-to-function" or "reference-to-function." Nonstatic member
6256 functions match targets of type "pointer-to-member-function;" the
6257 function type of the pointer to member is used to select the member
6258 function from the set of overloaded member functions.
6260 So figure out the FUNCTION_TYPE that we want to match against. */
6261 target_fn_type = static_fn_type (target_type);
6263 /* If we can find a non-template function that matches, we can just
6264 use it. There's no point in generating template instantiations
6265 if we're just going to throw them out anyhow. But, of course, we
6266 can only do this when we don't *need* a template function. */
6271 for (fns = overload; fns; fns = OVL_NEXT (fns))
6273 tree fn = OVL_CURRENT (fns);
6275 if (TREE_CODE (fn) == TEMPLATE_DECL)
6276 /* We're not looking for templates just yet. */
6279 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6281 /* We're looking for a non-static member, and this isn't
6282 one, or vice versa. */
6285 /* Ignore functions which haven't been explicitly
6287 if (DECL_ANTICIPATED (fn))
6290 /* See if there's a match. */
6291 if (same_type_p (target_fn_type, static_fn_type (fn)))
6292 matches = tree_cons (fn, NULL_TREE, matches);
6296 /* Now, if we've already got a match (or matches), there's no need
6297 to proceed to the template functions. But, if we don't have a
6298 match we need to look at them, too. */
6301 tree target_arg_types;
6302 tree target_ret_type;
6305 unsigned int nargs, ia;
6308 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6309 target_ret_type = TREE_TYPE (target_fn_type);
6311 nargs = list_length (target_arg_types);
6312 args = XALLOCAVEC (tree, nargs);
6313 for (arg = target_arg_types, ia = 0;
6314 arg != NULL_TREE && arg != void_list_node;
6315 arg = TREE_CHAIN (arg), ++ia)
6316 args[ia] = TREE_VALUE (arg);
6319 for (fns = overload; fns; fns = OVL_NEXT (fns))
6321 tree fn = OVL_CURRENT (fns);
6325 if (TREE_CODE (fn) != TEMPLATE_DECL)
6326 /* We're only looking for templates. */
6329 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6331 /* We're not looking for a non-static member, and this is
6332 one, or vice versa. */
6335 /* Try to do argument deduction. */
6336 targs = make_tree_vec (DECL_NTPARMS (fn));
6337 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6338 target_ret_type, DEDUCE_EXACT,
6340 /* Argument deduction failed. */
6343 /* Instantiate the template. */
6344 instantiation = instantiate_template (fn, targs, flags);
6345 if (instantiation == error_mark_node)
6346 /* Instantiation failed. */
6349 /* See if there's a match. */
6350 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
6351 matches = tree_cons (instantiation, fn, matches);
6354 /* Now, remove all but the most specialized of the matches. */
6357 tree match = most_specialized_instantiation (matches);
6359 if (match != error_mark_node)
6360 matches = tree_cons (TREE_PURPOSE (match),
6366 /* Now we should have exactly one function in MATCHES. */
6367 if (matches == NULL_TREE)
6369 /* There were *no* matches. */
6370 if (flags & tf_error)
6372 error ("no matches converting function %qD to type %q#T",
6373 DECL_NAME (OVL_CURRENT (overload)),
6376 /* print_candidates expects a chain with the functions in
6377 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6378 so why be clever?). */
6379 for (; overload; overload = OVL_NEXT (overload))
6380 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
6383 print_candidates (matches);
6385 return error_mark_node;
6387 else if (TREE_CHAIN (matches))
6389 /* There were too many matches. First check if they're all
6390 the same function. */
6393 fn = TREE_PURPOSE (matches);
6394 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6395 if (!decls_match (fn, TREE_PURPOSE (match)))
6400 if (flags & tf_error)
6402 error ("converting overloaded function %qD to type %q#T is ambiguous",
6403 DECL_NAME (OVL_FUNCTION (overload)),
6406 /* Since print_candidates expects the functions in the
6407 TREE_VALUE slot, we flip them here. */
6408 for (match = matches; match; match = TREE_CHAIN (match))
6409 TREE_VALUE (match) = TREE_PURPOSE (match);
6411 print_candidates (matches);
6414 return error_mark_node;
6418 /* Good, exactly one match. Now, convert it to the correct type. */
6419 fn = TREE_PURPOSE (matches);
6421 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6422 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6424 static int explained;
6426 if (!(flags & tf_error))
6427 return error_mark_node;
6429 permerror (input_location, "assuming pointer to member %qD", fn);
6432 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6437 /* If we're doing overload resolution purely for the purpose of
6438 determining conversion sequences, we should not consider the
6439 function used. If this conversion sequence is selected, the
6440 function will be marked as used at this point. */
6441 if (!(flags & tf_conv))
6443 /* Make =delete work with SFINAE. */
6444 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6445 return error_mark_node;
6450 /* We could not check access to member functions when this
6451 expression was originally created since we did not know at that
6452 time to which function the expression referred. */
6453 if (!(flags & tf_no_access_control)
6454 && DECL_FUNCTION_MEMBER_P (fn))
6456 gcc_assert (access_path);
6457 perform_or_defer_access_check (access_path, fn, fn);
6460 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6461 return cp_build_unary_op (ADDR_EXPR, fn, 0, flags);
6464 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6465 will mark the function as addressed, but here we must do it
6467 cxx_mark_addressable (fn);
6473 /* This function will instantiate the type of the expression given in
6474 RHS to match the type of LHSTYPE. If errors exist, then return
6475 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6476 we complain on errors. If we are not complaining, never modify rhs,
6477 as overload resolution wants to try many possible instantiations, in
6478 the hope that at least one will work.
6480 For non-recursive calls, LHSTYPE should be a function, pointer to
6481 function, or a pointer to member function. */
6484 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6486 tsubst_flags_t flags_in = flags;
6487 tree access_path = NULL_TREE;
6489 flags &= ~tf_ptrmem_ok;
6491 if (lhstype == unknown_type_node)
6493 if (flags & tf_error)
6494 error ("not enough type information");
6495 return error_mark_node;
6498 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6500 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6502 if (flag_ms_extensions
6503 && TYPE_PTRMEMFUNC_P (lhstype)
6504 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6505 /* Microsoft allows `A::f' to be resolved to a
6506 pointer-to-member. */
6510 if (flags & tf_error)
6511 error ("argument of type %qT does not match %qT",
6512 TREE_TYPE (rhs), lhstype);
6513 return error_mark_node;
6517 if (TREE_CODE (rhs) == BASELINK)
6519 access_path = BASELINK_ACCESS_BINFO (rhs);
6520 rhs = BASELINK_FUNCTIONS (rhs);
6523 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6524 deduce any type information. */
6525 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6527 if (flags & tf_error)
6528 error ("not enough type information");
6529 return error_mark_node;
6532 /* There only a few kinds of expressions that may have a type
6533 dependent on overload resolution. */
6534 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6535 || TREE_CODE (rhs) == COMPONENT_REF
6536 || really_overloaded_fn (rhs)
6537 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
6539 /* This should really only be used when attempting to distinguish
6540 what sort of a pointer to function we have. For now, any
6541 arithmetic operation which is not supported on pointers
6542 is rejected as an error. */
6544 switch (TREE_CODE (rhs))
6548 tree member = TREE_OPERAND (rhs, 1);
6550 member = instantiate_type (lhstype, member, flags);
6551 if (member != error_mark_node
6552 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6553 /* Do not lose object's side effects. */
6554 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6555 TREE_OPERAND (rhs, 0), member);
6560 rhs = TREE_OPERAND (rhs, 1);
6561 if (BASELINK_P (rhs))
6562 return instantiate_type (lhstype, rhs, flags_in);
6564 /* This can happen if we are forming a pointer-to-member for a
6566 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6570 case TEMPLATE_ID_EXPR:
6572 tree fns = TREE_OPERAND (rhs, 0);
6573 tree args = TREE_OPERAND (rhs, 1);
6576 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6577 /*template_only=*/true,
6584 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6585 /*template_only=*/false,
6586 /*explicit_targs=*/NULL_TREE,
6591 if (PTRMEM_OK_P (rhs))
6592 flags |= tf_ptrmem_ok;
6594 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6598 return error_mark_node;
6603 return error_mark_node;
6606 /* Return the name of the virtual function pointer field
6607 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6608 this may have to look back through base types to find the
6609 ultimate field name. (For single inheritance, these could
6610 all be the same name. Who knows for multiple inheritance). */
6613 get_vfield_name (tree type)
6615 tree binfo, base_binfo;
6618 for (binfo = TYPE_BINFO (type);
6619 BINFO_N_BASE_BINFOS (binfo);
6622 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6624 if (BINFO_VIRTUAL_P (base_binfo)
6625 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6629 type = BINFO_TYPE (binfo);
6630 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6631 + TYPE_NAME_LENGTH (type) + 2);
6632 sprintf (buf, VFIELD_NAME_FORMAT,
6633 IDENTIFIER_POINTER (constructor_name (type)));
6634 return get_identifier (buf);
6638 print_class_statistics (void)
6640 #ifdef GATHER_STATISTICS
6641 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6642 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6645 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6646 n_vtables, n_vtable_searches);
6647 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6648 n_vtable_entries, n_vtable_elems);
6653 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6654 according to [class]:
6655 The class-name is also inserted
6656 into the scope of the class itself. For purposes of access checking,
6657 the inserted class name is treated as if it were a public member name. */
6660 build_self_reference (void)
6662 tree name = constructor_name (current_class_type);
6663 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6666 DECL_NONLOCAL (value) = 1;
6667 DECL_CONTEXT (value) = current_class_type;
6668 DECL_ARTIFICIAL (value) = 1;
6669 SET_DECL_SELF_REFERENCE_P (value);
6670 cp_set_underlying_type (value);
6672 if (processing_template_decl)
6673 value = push_template_decl (value);
6675 saved_cas = current_access_specifier;
6676 current_access_specifier = access_public_node;
6677 finish_member_declaration (value);
6678 current_access_specifier = saved_cas;
6681 /* Returns 1 if TYPE contains only padding bytes. */
6684 is_empty_class (tree type)
6686 if (type == error_mark_node)
6689 if (! CLASS_TYPE_P (type))
6692 /* In G++ 3.2, whether or not a class was empty was determined by
6693 looking at its size. */
6694 if (abi_version_at_least (2))
6695 return CLASSTYPE_EMPTY_P (type);
6697 return integer_zerop (CLASSTYPE_SIZE (type));
6700 /* Returns true if TYPE contains an empty class. */
6703 contains_empty_class_p (tree type)
6705 if (is_empty_class (type))
6707 if (CLASS_TYPE_P (type))
6714 for (binfo = TYPE_BINFO (type), i = 0;
6715 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6716 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6718 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6719 if (TREE_CODE (field) == FIELD_DECL
6720 && !DECL_ARTIFICIAL (field)
6721 && is_empty_class (TREE_TYPE (field)))
6724 else if (TREE_CODE (type) == ARRAY_TYPE)
6725 return contains_empty_class_p (TREE_TYPE (type));
6729 /* Returns true if TYPE contains no actual data, just various
6730 possible combinations of empty classes. */
6733 is_really_empty_class (tree type)
6735 if (is_empty_class (type))
6737 if (CLASS_TYPE_P (type))
6744 for (binfo = TYPE_BINFO (type), i = 0;
6745 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6746 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
6748 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6749 if (TREE_CODE (field) == FIELD_DECL
6750 && !DECL_ARTIFICIAL (field)
6751 && !is_really_empty_class (TREE_TYPE (field)))
6755 else if (TREE_CODE (type) == ARRAY_TYPE)
6756 return is_really_empty_class (TREE_TYPE (type));
6760 /* Note that NAME was looked up while the current class was being
6761 defined and that the result of that lookup was DECL. */
6764 maybe_note_name_used_in_class (tree name, tree decl)
6766 splay_tree names_used;
6768 /* If we're not defining a class, there's nothing to do. */
6769 if (!(innermost_scope_kind() == sk_class
6770 && TYPE_BEING_DEFINED (current_class_type)
6771 && !LAMBDA_TYPE_P (current_class_type)))
6774 /* If there's already a binding for this NAME, then we don't have
6775 anything to worry about. */
6776 if (lookup_member (current_class_type, name,
6777 /*protect=*/0, /*want_type=*/false))
6780 if (!current_class_stack[current_class_depth - 1].names_used)
6781 current_class_stack[current_class_depth - 1].names_used
6782 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6783 names_used = current_class_stack[current_class_depth - 1].names_used;
6785 splay_tree_insert (names_used,
6786 (splay_tree_key) name,
6787 (splay_tree_value) decl);
6790 /* Note that NAME was declared (as DECL) in the current class. Check
6791 to see that the declaration is valid. */
6794 note_name_declared_in_class (tree name, tree decl)
6796 splay_tree names_used;
6799 /* Look to see if we ever used this name. */
6801 = current_class_stack[current_class_depth - 1].names_used;
6805 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6808 /* [basic.scope.class]
6810 A name N used in a class S shall refer to the same declaration
6811 in its context and when re-evaluated in the completed scope of
6813 permerror (input_location, "declaration of %q#D", decl);
6814 permerror (input_location, "changes meaning of %qD from %q+#D",
6815 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6819 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6820 Secondary vtables are merged with primary vtables; this function
6821 will return the VAR_DECL for the primary vtable. */
6824 get_vtbl_decl_for_binfo (tree binfo)
6828 decl = BINFO_VTABLE (binfo);
6829 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
6831 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6832 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6835 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6840 /* Returns the binfo for the primary base of BINFO. If the resulting
6841 BINFO is a virtual base, and it is inherited elsewhere in the
6842 hierarchy, then the returned binfo might not be the primary base of
6843 BINFO in the complete object. Check BINFO_PRIMARY_P or
6844 BINFO_LOST_PRIMARY_P to be sure. */
6847 get_primary_binfo (tree binfo)
6851 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6855 return copied_binfo (primary_base, binfo);
6858 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6861 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6864 fprintf (stream, "%*s", indent, "");
6868 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6869 INDENT should be zero when called from the top level; it is
6870 incremented recursively. IGO indicates the next expected BINFO in
6871 inheritance graph ordering. */
6874 dump_class_hierarchy_r (FILE *stream,
6884 indented = maybe_indent_hierarchy (stream, indent, 0);
6885 fprintf (stream, "%s (0x%lx) ",
6886 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6887 (unsigned long) binfo);
6890 fprintf (stream, "alternative-path\n");
6893 igo = TREE_CHAIN (binfo);
6895 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6896 tree_low_cst (BINFO_OFFSET (binfo), 0));
6897 if (is_empty_class (BINFO_TYPE (binfo)))
6898 fprintf (stream, " empty");
6899 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6900 fprintf (stream, " nearly-empty");
6901 if (BINFO_VIRTUAL_P (binfo))
6902 fprintf (stream, " virtual");
6903 fprintf (stream, "\n");
6906 if (BINFO_PRIMARY_P (binfo))
6908 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6909 fprintf (stream, " primary-for %s (0x%lx)",
6910 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6911 TFF_PLAIN_IDENTIFIER),
6912 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6914 if (BINFO_LOST_PRIMARY_P (binfo))
6916 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6917 fprintf (stream, " lost-primary");
6920 fprintf (stream, "\n");
6922 if (!(flags & TDF_SLIM))
6926 if (BINFO_SUBVTT_INDEX (binfo))
6928 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6929 fprintf (stream, " subvttidx=%s",
6930 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6931 TFF_PLAIN_IDENTIFIER));
6933 if (BINFO_VPTR_INDEX (binfo))
6935 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6936 fprintf (stream, " vptridx=%s",
6937 expr_as_string (BINFO_VPTR_INDEX (binfo),
6938 TFF_PLAIN_IDENTIFIER));
6940 if (BINFO_VPTR_FIELD (binfo))
6942 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6943 fprintf (stream, " vbaseoffset=%s",
6944 expr_as_string (BINFO_VPTR_FIELD (binfo),
6945 TFF_PLAIN_IDENTIFIER));
6947 if (BINFO_VTABLE (binfo))
6949 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6950 fprintf (stream, " vptr=%s",
6951 expr_as_string (BINFO_VTABLE (binfo),
6952 TFF_PLAIN_IDENTIFIER));
6956 fprintf (stream, "\n");
6959 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6960 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6965 /* Dump the BINFO hierarchy for T. */
6968 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6970 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6971 fprintf (stream, " size=%lu align=%lu\n",
6972 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6973 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6974 fprintf (stream, " base size=%lu base align=%lu\n",
6975 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6977 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6979 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6980 fprintf (stream, "\n");
6983 /* Debug interface to hierarchy dumping. */
6986 debug_class (tree t)
6988 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6992 dump_class_hierarchy (tree t)
6995 FILE *stream = dump_begin (TDI_class, &flags);
6999 dump_class_hierarchy_1 (stream, flags, t);
7000 dump_end (TDI_class, stream);
7005 dump_array (FILE * stream, tree decl)
7008 unsigned HOST_WIDE_INT ix;
7010 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
7012 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
7014 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
7015 fprintf (stream, " %s entries",
7016 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
7017 TFF_PLAIN_IDENTIFIER));
7018 fprintf (stream, "\n");
7020 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
7022 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
7023 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
7027 dump_vtable (tree t, tree binfo, tree vtable)
7030 FILE *stream = dump_begin (TDI_class, &flags);
7035 if (!(flags & TDF_SLIM))
7037 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
7039 fprintf (stream, "%s for %s",
7040 ctor_vtbl_p ? "Construction vtable" : "Vtable",
7041 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
7044 if (!BINFO_VIRTUAL_P (binfo))
7045 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
7046 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7048 fprintf (stream, "\n");
7049 dump_array (stream, vtable);
7050 fprintf (stream, "\n");
7053 dump_end (TDI_class, stream);
7057 dump_vtt (tree t, tree vtt)
7060 FILE *stream = dump_begin (TDI_class, &flags);
7065 if (!(flags & TDF_SLIM))
7067 fprintf (stream, "VTT for %s\n",
7068 type_as_string (t, TFF_PLAIN_IDENTIFIER));
7069 dump_array (stream, vtt);
7070 fprintf (stream, "\n");
7073 dump_end (TDI_class, stream);
7076 /* Dump a function or thunk and its thunkees. */
7079 dump_thunk (FILE *stream, int indent, tree thunk)
7081 static const char spaces[] = " ";
7082 tree name = DECL_NAME (thunk);
7085 fprintf (stream, "%.*s%p %s %s", indent, spaces,
7087 !DECL_THUNK_P (thunk) ? "function"
7088 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
7089 name ? IDENTIFIER_POINTER (name) : "<unset>");
7090 if (DECL_THUNK_P (thunk))
7092 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
7093 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
7095 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
7096 if (!virtual_adjust)
7098 else if (DECL_THIS_THUNK_P (thunk))
7099 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
7100 tree_low_cst (virtual_adjust, 0));
7102 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
7103 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
7104 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
7105 if (THUNK_ALIAS (thunk))
7106 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
7108 fprintf (stream, "\n");
7109 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
7110 dump_thunk (stream, indent + 2, thunks);
7113 /* Dump the thunks for FN. */
7116 debug_thunks (tree fn)
7118 dump_thunk (stderr, 0, fn);
7121 /* Virtual function table initialization. */
7123 /* Create all the necessary vtables for T and its base classes. */
7126 finish_vtbls (tree t)
7129 VEC(constructor_elt,gc) *v = NULL;
7130 tree vtable = BINFO_VTABLE (TYPE_BINFO (t));
7132 /* We lay out the primary and secondary vtables in one contiguous
7133 vtable. The primary vtable is first, followed by the non-virtual
7134 secondary vtables in inheritance graph order. */
7135 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t),
7138 /* Then come the virtual bases, also in inheritance graph order. */
7139 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
7141 if (!BINFO_VIRTUAL_P (vbase))
7143 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), vtable, t, &v);
7146 if (BINFO_VTABLE (TYPE_BINFO (t)))
7147 initialize_vtable (TYPE_BINFO (t), v);
7150 /* Initialize the vtable for BINFO with the INITS. */
7153 initialize_vtable (tree binfo, VEC(constructor_elt,gc) *inits)
7157 layout_vtable_decl (binfo, VEC_length (constructor_elt, inits));
7158 decl = get_vtbl_decl_for_binfo (binfo);
7159 initialize_artificial_var (decl, inits);
7160 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
7163 /* Build the VTT (virtual table table) for T.
7164 A class requires a VTT if it has virtual bases.
7167 1 - primary virtual pointer for complete object T
7168 2 - secondary VTTs for each direct non-virtual base of T which requires a
7170 3 - secondary virtual pointers for each direct or indirect base of T which
7171 has virtual bases or is reachable via a virtual path from T.
7172 4 - secondary VTTs for each direct or indirect virtual base of T.
7174 Secondary VTTs look like complete object VTTs without part 4. */
7182 VEC(constructor_elt,gc) *inits;
7184 /* Build up the initializers for the VTT. */
7186 index = size_zero_node;
7187 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7189 /* If we didn't need a VTT, we're done. */
7193 /* Figure out the type of the VTT. */
7194 type = build_index_type (size_int (VEC_length (constructor_elt, inits) - 1));
7195 type = build_cplus_array_type (const_ptr_type_node, type);
7197 /* Now, build the VTT object itself. */
7198 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7199 initialize_artificial_var (vtt, inits);
7200 /* Add the VTT to the vtables list. */
7201 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
7202 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7207 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7208 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7209 and CHAIN the vtable pointer for this binfo after construction is
7210 complete. VALUE can also be another BINFO, in which case we recurse. */
7213 binfo_ctor_vtable (tree binfo)
7219 vt = BINFO_VTABLE (binfo);
7220 if (TREE_CODE (vt) == TREE_LIST)
7221 vt = TREE_VALUE (vt);
7222 if (TREE_CODE (vt) == TREE_BINFO)
7231 /* Data for secondary VTT initialization. */
7232 typedef struct secondary_vptr_vtt_init_data_s
7234 /* Is this the primary VTT? */
7237 /* Current index into the VTT. */
7240 /* Vector of initializers built up. */
7241 VEC(constructor_elt,gc) *inits;
7243 /* The type being constructed by this secondary VTT. */
7244 tree type_being_constructed;
7245 } secondary_vptr_vtt_init_data;
7247 /* Recursively build the VTT-initializer for BINFO (which is in the
7248 hierarchy dominated by T). INITS points to the end of the initializer
7249 list to date. INDEX is the VTT index where the next element will be
7250 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7251 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7252 for virtual bases of T. When it is not so, we build the constructor
7253 vtables for the BINFO-in-T variant. */
7256 build_vtt_inits (tree binfo, tree t, VEC(constructor_elt,gc) **inits, tree *index)
7261 secondary_vptr_vtt_init_data data;
7262 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7264 /* We only need VTTs for subobjects with virtual bases. */
7265 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7268 /* We need to use a construction vtable if this is not the primary
7272 build_ctor_vtbl_group (binfo, t);
7274 /* Record the offset in the VTT where this sub-VTT can be found. */
7275 BINFO_SUBVTT_INDEX (binfo) = *index;
7278 /* Add the address of the primary vtable for the complete object. */
7279 init = binfo_ctor_vtable (binfo);
7280 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7283 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7284 BINFO_VPTR_INDEX (binfo) = *index;
7286 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7288 /* Recursively add the secondary VTTs for non-virtual bases. */
7289 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7290 if (!BINFO_VIRTUAL_P (b))
7291 build_vtt_inits (b, t, inits, index);
7293 /* Add secondary virtual pointers for all subobjects of BINFO with
7294 either virtual bases or reachable along a virtual path, except
7295 subobjects that are non-virtual primary bases. */
7296 data.top_level_p = top_level_p;
7297 data.index = *index;
7298 data.inits = *inits;
7299 data.type_being_constructed = BINFO_TYPE (binfo);
7301 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7303 *index = data.index;
7305 /* data.inits might have grown as we added secondary virtual pointers.
7306 Make sure our caller knows about the new vector. */
7307 *inits = data.inits;
7310 /* Add the secondary VTTs for virtual bases in inheritance graph
7312 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7314 if (!BINFO_VIRTUAL_P (b))
7317 build_vtt_inits (b, t, inits, index);
7320 /* Remove the ctor vtables we created. */
7321 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7324 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7325 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7328 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7330 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7332 /* We don't care about bases that don't have vtables. */
7333 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7334 return dfs_skip_bases;
7336 /* We're only interested in proper subobjects of the type being
7338 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7341 /* We're only interested in bases with virtual bases or reachable
7342 via a virtual path from the type being constructed. */
7343 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7344 || binfo_via_virtual (binfo, data->type_being_constructed)))
7345 return dfs_skip_bases;
7347 /* We're not interested in non-virtual primary bases. */
7348 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7351 /* Record the index where this secondary vptr can be found. */
7352 if (data->top_level_p)
7354 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7355 BINFO_VPTR_INDEX (binfo) = data->index;
7357 if (BINFO_VIRTUAL_P (binfo))
7359 /* It's a primary virtual base, and this is not a
7360 construction vtable. Find the base this is primary of in
7361 the inheritance graph, and use that base's vtable
7363 while (BINFO_PRIMARY_P (binfo))
7364 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7368 /* Add the initializer for the secondary vptr itself. */
7369 CONSTRUCTOR_APPEND_ELT (data->inits, NULL_TREE, binfo_ctor_vtable (binfo));
7371 /* Advance the vtt index. */
7372 data->index = size_binop (PLUS_EXPR, data->index,
7373 TYPE_SIZE_UNIT (ptr_type_node));
7378 /* Called from build_vtt_inits via dfs_walk. After building
7379 constructor vtables and generating the sub-vtt from them, we need
7380 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7381 binfo of the base whose sub vtt was generated. */
7384 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7386 tree vtable = BINFO_VTABLE (binfo);
7388 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7389 /* If this class has no vtable, none of its bases do. */
7390 return dfs_skip_bases;
7393 /* This might be a primary base, so have no vtable in this
7397 /* If we scribbled the construction vtable vptr into BINFO, clear it
7399 if (TREE_CODE (vtable) == TREE_LIST
7400 && (TREE_PURPOSE (vtable) == (tree) data))
7401 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7406 /* Build the construction vtable group for BINFO which is in the
7407 hierarchy dominated by T. */
7410 build_ctor_vtbl_group (tree binfo, tree t)
7416 VEC(constructor_elt,gc) *v;
7418 /* See if we've already created this construction vtable group. */
7419 id = mangle_ctor_vtbl_for_type (t, binfo);
7420 if (IDENTIFIER_GLOBAL_VALUE (id))
7423 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7424 /* Build a version of VTBL (with the wrong type) for use in
7425 constructing the addresses of secondary vtables in the
7426 construction vtable group. */
7427 vtbl = build_vtable (t, id, ptr_type_node);
7428 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7431 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7432 binfo, vtbl, t, &v);
7434 /* Add the vtables for each of our virtual bases using the vbase in T
7436 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7438 vbase = TREE_CHAIN (vbase))
7442 if (!BINFO_VIRTUAL_P (vbase))
7444 b = copied_binfo (vbase, binfo);
7446 accumulate_vtbl_inits (b, vbase, binfo, vtbl, t, &v);
7449 /* Figure out the type of the construction vtable. */
7450 type = build_index_type (size_int (VEC_length (constructor_elt, v) - 1));
7451 type = build_cplus_array_type (vtable_entry_type, type);
7453 TREE_TYPE (vtbl) = type;
7454 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7455 layout_decl (vtbl, 0);
7457 /* Initialize the construction vtable. */
7458 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7459 initialize_artificial_var (vtbl, v);
7460 dump_vtable (t, binfo, vtbl);
7463 /* Add the vtbl initializers for BINFO (and its bases other than
7464 non-virtual primaries) to the list of INITS. BINFO is in the
7465 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7466 the constructor the vtbl inits should be accumulated for. (If this
7467 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7468 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7469 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7470 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7471 but are not necessarily the same in terms of layout. */
7474 accumulate_vtbl_inits (tree binfo,
7479 VEC(constructor_elt,gc) **inits)
7483 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7485 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7487 /* If it doesn't have a vptr, we don't do anything. */
7488 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7491 /* If we're building a construction vtable, we're not interested in
7492 subobjects that don't require construction vtables. */
7494 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7495 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7498 /* Build the initializers for the BINFO-in-T vtable. */
7499 dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, vtbl, t, inits);
7501 /* Walk the BINFO and its bases. We walk in preorder so that as we
7502 initialize each vtable we can figure out at what offset the
7503 secondary vtable lies from the primary vtable. We can't use
7504 dfs_walk here because we need to iterate through bases of BINFO
7505 and RTTI_BINFO simultaneously. */
7506 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7508 /* Skip virtual bases. */
7509 if (BINFO_VIRTUAL_P (base_binfo))
7511 accumulate_vtbl_inits (base_binfo,
7512 BINFO_BASE_BINFO (orig_binfo, i),
7513 rtti_binfo, vtbl, t,
7518 /* Called from accumulate_vtbl_inits. Adds the initializers for the
7519 BINFO vtable to L. */
7522 dfs_accumulate_vtbl_inits (tree binfo,
7527 VEC(constructor_elt,gc) **l)
7529 tree vtbl = NULL_TREE;
7530 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7534 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7536 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7537 primary virtual base. If it is not the same primary in
7538 the hierarchy of T, we'll need to generate a ctor vtable
7539 for it, to place at its location in T. If it is the same
7540 primary, we still need a VTT entry for the vtable, but it
7541 should point to the ctor vtable for the base it is a
7542 primary for within the sub-hierarchy of RTTI_BINFO.
7544 There are three possible cases:
7546 1) We are in the same place.
7547 2) We are a primary base within a lost primary virtual base of
7549 3) We are primary to something not a base of RTTI_BINFO. */
7552 tree last = NULL_TREE;
7554 /* First, look through the bases we are primary to for RTTI_BINFO
7555 or a virtual base. */
7557 while (BINFO_PRIMARY_P (b))
7559 b = BINFO_INHERITANCE_CHAIN (b);
7561 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7564 /* If we run out of primary links, keep looking down our
7565 inheritance chain; we might be an indirect primary. */
7566 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7567 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7571 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7572 base B and it is a base of RTTI_BINFO, this is case 2. In
7573 either case, we share our vtable with LAST, i.e. the
7574 derived-most base within B of which we are a primary. */
7576 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7577 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7578 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7579 binfo_ctor_vtable after everything's been set up. */
7582 /* Otherwise, this is case 3 and we get our own. */
7584 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7587 n_inits = VEC_length (constructor_elt, *l);
7594 /* Add the initializer for this vtable. */
7595 build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7596 &non_fn_entries, l);
7598 /* Figure out the position to which the VPTR should point. */
7599 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, orig_vtbl);
7600 index = size_binop (PLUS_EXPR,
7601 size_int (non_fn_entries),
7602 size_int (n_inits));
7603 index = size_binop (MULT_EXPR,
7604 TYPE_SIZE_UNIT (vtable_entry_type),
7606 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7610 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7611 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7612 straighten this out. */
7613 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7614 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7615 /* Throw away any unneeded intializers. */
7616 VEC_truncate (constructor_elt, *l, n_inits);
7618 /* For an ordinary vtable, set BINFO_VTABLE. */
7619 BINFO_VTABLE (binfo) = vtbl;
7622 static GTY(()) tree abort_fndecl_addr;
7624 /* Construct the initializer for BINFO's virtual function table. BINFO
7625 is part of the hierarchy dominated by T. If we're building a
7626 construction vtable, the ORIG_BINFO is the binfo we should use to
7627 find the actual function pointers to put in the vtable - but they
7628 can be overridden on the path to most-derived in the graph that
7629 ORIG_BINFO belongs. Otherwise,
7630 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7631 BINFO that should be indicated by the RTTI information in the
7632 vtable; it will be a base class of T, rather than T itself, if we
7633 are building a construction vtable.
7635 The value returned is a TREE_LIST suitable for wrapping in a
7636 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7637 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7638 number of non-function entries in the vtable.
7640 It might seem that this function should never be called with a
7641 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7642 base is always subsumed by a derived class vtable. However, when
7643 we are building construction vtables, we do build vtables for
7644 primary bases; we need these while the primary base is being
7648 build_vtbl_initializer (tree binfo,
7652 int* non_fn_entries_p,
7653 VEC(constructor_elt,gc) **inits)
7659 VEC(tree,gc) *vbases;
7662 /* Initialize VID. */
7663 memset (&vid, 0, sizeof (vid));
7666 vid.rtti_binfo = rtti_binfo;
7667 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7668 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7669 vid.generate_vcall_entries = true;
7670 /* The first vbase or vcall offset is at index -3 in the vtable. */
7671 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7673 /* Add entries to the vtable for RTTI. */
7674 build_rtti_vtbl_entries (binfo, &vid);
7676 /* Create an array for keeping track of the functions we've
7677 processed. When we see multiple functions with the same
7678 signature, we share the vcall offsets. */
7679 vid.fns = VEC_alloc (tree, gc, 32);
7680 /* Add the vcall and vbase offset entries. */
7681 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7683 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7684 build_vbase_offset_vtbl_entries. */
7685 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7686 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7687 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7689 /* If the target requires padding between data entries, add that now. */
7690 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7692 int n_entries = VEC_length (constructor_elt, vid.inits);
7694 VEC_safe_grow (constructor_elt, gc, vid.inits,
7695 TARGET_VTABLE_DATA_ENTRY_DISTANCE * n_entries);
7697 /* Move data entries into their new positions and add padding
7698 after the new positions. Iterate backwards so we don't
7699 overwrite entries that we would need to process later. */
7700 for (ix = n_entries - 1;
7701 VEC_iterate (constructor_elt, vid.inits, ix, e);
7705 int new_position = (TARGET_VTABLE_DATA_ENTRY_DISTANCE * ix
7706 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE - 1));
7708 VEC_replace (constructor_elt, vid.inits, new_position, e);
7710 for (j = 1; j < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++j)
7712 constructor_elt *f = VEC_index (constructor_elt, vid.inits,
7714 f->index = NULL_TREE;
7715 f->value = build1 (NOP_EXPR, vtable_entry_type,
7721 if (non_fn_entries_p)
7722 *non_fn_entries_p = VEC_length (constructor_elt, vid.inits);
7724 /* The initializers for virtual functions were built up in reverse
7725 order. Straighten them out and add them to the running list in one
7727 jx = VEC_length (constructor_elt, *inits);
7728 VEC_safe_grow (constructor_elt, gc, *inits,
7729 (jx + VEC_length (constructor_elt, vid.inits)));
7731 for (ix = VEC_length (constructor_elt, vid.inits) - 1;
7732 VEC_iterate (constructor_elt, vid.inits, ix, e);
7734 VEC_replace (constructor_elt, *inits, jx, e);
7736 /* Go through all the ordinary virtual functions, building up
7738 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7742 tree fn, fn_original;
7743 tree init = NULL_TREE;
7747 if (DECL_THUNK_P (fn))
7749 if (!DECL_NAME (fn))
7751 if (THUNK_ALIAS (fn))
7753 fn = THUNK_ALIAS (fn);
7756 fn_original = THUNK_TARGET (fn);
7759 /* If the only definition of this function signature along our
7760 primary base chain is from a lost primary, this vtable slot will
7761 never be used, so just zero it out. This is important to avoid
7762 requiring extra thunks which cannot be generated with the function.
7764 We first check this in update_vtable_entry_for_fn, so we handle
7765 restored primary bases properly; we also need to do it here so we
7766 zero out unused slots in ctor vtables, rather than filling them
7767 with erroneous values (though harmless, apart from relocation
7769 if (BV_LOST_PRIMARY (v))
7770 init = size_zero_node;
7774 /* Pull the offset for `this', and the function to call, out of
7776 delta = BV_DELTA (v);
7777 vcall_index = BV_VCALL_INDEX (v);
7779 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7780 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7782 /* You can't call an abstract virtual function; it's abstract.
7783 So, we replace these functions with __pure_virtual. */
7784 if (DECL_PURE_VIRTUAL_P (fn_original))
7787 if (abort_fndecl_addr == NULL)
7788 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7789 init = abort_fndecl_addr;
7793 if (!integer_zerop (delta) || vcall_index)
7795 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7796 if (!DECL_NAME (fn))
7799 /* Take the address of the function, considering it to be of an
7800 appropriate generic type. */
7801 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7805 /* And add it to the chain of initializers. */
7806 if (TARGET_VTABLE_USES_DESCRIPTORS)
7809 if (init == size_zero_node)
7810 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7811 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7813 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7815 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7816 TREE_OPERAND (init, 0),
7817 build_int_cst (NULL_TREE, i));
7818 TREE_CONSTANT (fdesc) = 1;
7820 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, fdesc);
7824 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7828 /* Adds to vid->inits the initializers for the vbase and vcall
7829 offsets in BINFO, which is in the hierarchy dominated by T. */
7832 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7836 /* If this is a derived class, we must first create entries
7837 corresponding to the primary base class. */
7838 b = get_primary_binfo (binfo);
7840 build_vcall_and_vbase_vtbl_entries (b, vid);
7842 /* Add the vbase entries for this base. */
7843 build_vbase_offset_vtbl_entries (binfo, vid);
7844 /* Add the vcall entries for this base. */
7845 build_vcall_offset_vtbl_entries (binfo, vid);
7848 /* Returns the initializers for the vbase offset entries in the vtable
7849 for BINFO (which is part of the class hierarchy dominated by T), in
7850 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7851 where the next vbase offset will go. */
7854 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7858 tree non_primary_binfo;
7860 /* If there are no virtual baseclasses, then there is nothing to
7862 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7867 /* We might be a primary base class. Go up the inheritance hierarchy
7868 until we find the most derived class of which we are a primary base:
7869 it is the offset of that which we need to use. */
7870 non_primary_binfo = binfo;
7871 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7875 /* If we have reached a virtual base, then it must be a primary
7876 base (possibly multi-level) of vid->binfo, or we wouldn't
7877 have called build_vcall_and_vbase_vtbl_entries for it. But it
7878 might be a lost primary, so just skip down to vid->binfo. */
7879 if (BINFO_VIRTUAL_P (non_primary_binfo))
7881 non_primary_binfo = vid->binfo;
7885 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7886 if (get_primary_binfo (b) != non_primary_binfo)
7888 non_primary_binfo = b;
7891 /* Go through the virtual bases, adding the offsets. */
7892 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7894 vbase = TREE_CHAIN (vbase))
7899 if (!BINFO_VIRTUAL_P (vbase))
7902 /* Find the instance of this virtual base in the complete
7904 b = copied_binfo (vbase, binfo);
7906 /* If we've already got an offset for this virtual base, we
7907 don't need another one. */
7908 if (BINFO_VTABLE_PATH_MARKED (b))
7910 BINFO_VTABLE_PATH_MARKED (b) = 1;
7912 /* Figure out where we can find this vbase offset. */
7913 delta = size_binop (MULT_EXPR,
7916 TYPE_SIZE_UNIT (vtable_entry_type)));
7917 if (vid->primary_vtbl_p)
7918 BINFO_VPTR_FIELD (b) = delta;
7920 if (binfo != TYPE_BINFO (t))
7921 /* The vbase offset had better be the same. */
7922 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7924 /* The next vbase will come at a more negative offset. */
7925 vid->index = size_binop (MINUS_EXPR, vid->index,
7926 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7928 /* The initializer is the delta from BINFO to this virtual base.
7929 The vbase offsets go in reverse inheritance-graph order, and
7930 we are walking in inheritance graph order so these end up in
7932 delta = size_diffop_loc (input_location,
7933 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7935 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE,
7936 fold_build1_loc (input_location, NOP_EXPR,
7937 vtable_entry_type, delta));
7941 /* Adds the initializers for the vcall offset entries in the vtable
7942 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7946 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7948 /* We only need these entries if this base is a virtual base. We
7949 compute the indices -- but do not add to the vtable -- when
7950 building the main vtable for a class. */
7951 if (binfo == TYPE_BINFO (vid->derived)
7952 || (BINFO_VIRTUAL_P (binfo)
7953 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7954 correspond to VID->DERIVED), we are building a primary
7955 construction virtual table. Since this is a primary
7956 virtual table, we do not need the vcall offsets for
7958 && binfo != vid->rtti_binfo))
7960 /* We need a vcall offset for each of the virtual functions in this
7961 vtable. For example:
7963 class A { virtual void f (); };
7964 class B1 : virtual public A { virtual void f (); };
7965 class B2 : virtual public A { virtual void f (); };
7966 class C: public B1, public B2 { virtual void f (); };
7968 A C object has a primary base of B1, which has a primary base of A. A
7969 C also has a secondary base of B2, which no longer has a primary base
7970 of A. So the B2-in-C construction vtable needs a secondary vtable for
7971 A, which will adjust the A* to a B2* to call f. We have no way of
7972 knowing what (or even whether) this offset will be when we define B2,
7973 so we store this "vcall offset" in the A sub-vtable and look it up in
7974 a "virtual thunk" for B2::f.
7976 We need entries for all the functions in our primary vtable and
7977 in our non-virtual bases' secondary vtables. */
7979 /* If we are just computing the vcall indices -- but do not need
7980 the actual entries -- not that. */
7981 if (!BINFO_VIRTUAL_P (binfo))
7982 vid->generate_vcall_entries = false;
7983 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7984 add_vcall_offset_vtbl_entries_r (binfo, vid);
7988 /* Build vcall offsets, starting with those for BINFO. */
7991 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7997 /* Don't walk into virtual bases -- except, of course, for the
7998 virtual base for which we are building vcall offsets. Any
7999 primary virtual base will have already had its offsets generated
8000 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8001 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
8004 /* If BINFO has a primary base, process it first. */
8005 primary_binfo = get_primary_binfo (binfo);
8007 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
8009 /* Add BINFO itself to the list. */
8010 add_vcall_offset_vtbl_entries_1 (binfo, vid);
8012 /* Scan the non-primary bases of BINFO. */
8013 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8014 if (base_binfo != primary_binfo)
8015 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
8018 /* Called from build_vcall_offset_vtbl_entries_r. */
8021 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
8023 /* Make entries for the rest of the virtuals. */
8024 if (abi_version_at_least (2))
8028 /* The ABI requires that the methods be processed in declaration
8029 order. G++ 3.2 used the order in the vtable. */
8030 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
8032 orig_fn = TREE_CHAIN (orig_fn))
8033 if (DECL_VINDEX (orig_fn))
8034 add_vcall_offset (orig_fn, binfo, vid);
8038 tree derived_virtuals;
8041 /* If BINFO is a primary base, the most derived class which has
8042 BINFO as a primary base; otherwise, just BINFO. */
8043 tree non_primary_binfo;
8045 /* We might be a primary base class. Go up the inheritance hierarchy
8046 until we find the most derived class of which we are a primary base:
8047 it is the BINFO_VIRTUALS there that we need to consider. */
8048 non_primary_binfo = binfo;
8049 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8053 /* If we have reached a virtual base, then it must be vid->vbase,
8054 because we ignore other virtual bases in
8055 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8056 base (possibly multi-level) of vid->binfo, or we wouldn't
8057 have called build_vcall_and_vbase_vtbl_entries for it. But it
8058 might be a lost primary, so just skip down to vid->binfo. */
8059 if (BINFO_VIRTUAL_P (non_primary_binfo))
8061 gcc_assert (non_primary_binfo == vid->vbase);
8062 non_primary_binfo = vid->binfo;
8066 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8067 if (get_primary_binfo (b) != non_primary_binfo)
8069 non_primary_binfo = b;
8072 if (vid->ctor_vtbl_p)
8073 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8074 where rtti_binfo is the most derived type. */
8076 = original_binfo (non_primary_binfo, vid->rtti_binfo);
8078 for (base_virtuals = BINFO_VIRTUALS (binfo),
8079 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
8080 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
8082 base_virtuals = TREE_CHAIN (base_virtuals),
8083 derived_virtuals = TREE_CHAIN (derived_virtuals),
8084 orig_virtuals = TREE_CHAIN (orig_virtuals))
8088 /* Find the declaration that originally caused this function to
8089 be present in BINFO_TYPE (binfo). */
8090 orig_fn = BV_FN (orig_virtuals);
8092 /* When processing BINFO, we only want to generate vcall slots for
8093 function slots introduced in BINFO. So don't try to generate
8094 one if the function isn't even defined in BINFO. */
8095 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
8098 add_vcall_offset (orig_fn, binfo, vid);
8103 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8106 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
8112 /* If there is already an entry for a function with the same
8113 signature as FN, then we do not need a second vcall offset.
8114 Check the list of functions already present in the derived
8116 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
8118 if (same_signature_p (derived_entry, orig_fn)
8119 /* We only use one vcall offset for virtual destructors,
8120 even though there are two virtual table entries. */
8121 || (DECL_DESTRUCTOR_P (derived_entry)
8122 && DECL_DESTRUCTOR_P (orig_fn)))
8126 /* If we are building these vcall offsets as part of building
8127 the vtable for the most derived class, remember the vcall
8129 if (vid->binfo == TYPE_BINFO (vid->derived))
8131 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
8132 CLASSTYPE_VCALL_INDICES (vid->derived),
8134 elt->purpose = orig_fn;
8135 elt->value = vid->index;
8138 /* The next vcall offset will be found at a more negative
8140 vid->index = size_binop (MINUS_EXPR, vid->index,
8141 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8143 /* Keep track of this function. */
8144 VEC_safe_push (tree, gc, vid->fns, orig_fn);
8146 if (vid->generate_vcall_entries)
8151 /* Find the overriding function. */
8152 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8153 if (fn == error_mark_node)
8154 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
8158 base = TREE_VALUE (fn);
8160 /* The vbase we're working on is a primary base of
8161 vid->binfo. But it might be a lost primary, so its
8162 BINFO_OFFSET might be wrong, so we just use the
8163 BINFO_OFFSET from vid->binfo. */
8164 vcall_offset = size_diffop_loc (input_location,
8165 BINFO_OFFSET (base),
8166 BINFO_OFFSET (vid->binfo));
8167 vcall_offset = fold_build1_loc (input_location,
8168 NOP_EXPR, vtable_entry_type,
8171 /* Add the initializer to the vtable. */
8172 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, vcall_offset);
8176 /* Return vtbl initializers for the RTTI entries corresponding to the
8177 BINFO's vtable. The RTTI entries should indicate the object given
8178 by VID->rtti_binfo. */
8181 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8189 t = BINFO_TYPE (vid->rtti_binfo);
8191 /* To find the complete object, we will first convert to our most
8192 primary base, and then add the offset in the vtbl to that value. */
8194 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8195 && !BINFO_LOST_PRIMARY_P (b))
8199 primary_base = get_primary_binfo (b);
8200 gcc_assert (BINFO_PRIMARY_P (primary_base)
8201 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8204 offset = size_diffop_loc (input_location,
8205 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8207 /* The second entry is the address of the typeinfo object. */
8209 decl = build_address (get_tinfo_decl (t));
8211 decl = integer_zero_node;
8213 /* Convert the declaration to a type that can be stored in the
8215 init = build_nop (vfunc_ptr_type_node, decl);
8216 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8218 /* Add the offset-to-top entry. It comes earlier in the vtable than
8219 the typeinfo entry. Convert the offset to look like a
8220 function pointer, so that we can put it in the vtable. */
8221 init = build_nop (vfunc_ptr_type_node, offset);
8222 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8225 /* Fold a OBJ_TYPE_REF expression to the address of a function.
8226 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
8229 cp_fold_obj_type_ref (tree ref, tree known_type)
8231 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
8232 HOST_WIDE_INT i = 0;
8233 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
8238 i += (TARGET_VTABLE_USES_DESCRIPTORS
8239 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
8245 #ifdef ENABLE_CHECKING
8246 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
8247 DECL_VINDEX (fndecl)));
8250 cgraph_node (fndecl)->local.vtable_method = true;
8252 return build_address (fndecl);
8255 #include "gt-cp-class.h"