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
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"
39 #include "tree-dump.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. */
81 /* The last (i.e., most negative) entry in INITS. */
83 /* The binfo for the virtual base for which we're building
84 vcall offset initializers. */
86 /* The functions in vbase for which we have already provided vcall
89 /* The vtable index of the next vcall or vbase offset. */
91 /* Nonzero if we are building the initializer for the primary
94 /* Nonzero if we are building the initializer for a construction
97 /* True when adding vcall offset entries to the vtable. False when
98 merely computing the indices. */
99 bool generate_vcall_entries;
102 /* The type of a function passed to walk_subobject_offsets. */
103 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
105 /* The stack itself. This is a dynamically resized array. The
106 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
107 static int current_class_stack_size;
108 static class_stack_node_t current_class_stack;
110 /* The size of the largest empty class seen in this translation unit. */
111 static GTY (()) tree sizeof_biggest_empty_class;
113 /* An array of all local classes present in this translation unit, in
114 declaration order. */
115 VEC(tree,gc) *local_classes;
117 static tree get_vfield_name (tree);
118 static void finish_struct_anon (tree);
119 static tree get_vtable_name (tree);
120 static tree get_basefndecls (tree, tree);
121 static int build_primary_vtable (tree, tree);
122 static int build_secondary_vtable (tree);
123 static void finish_vtbls (tree);
124 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
125 static void finish_struct_bits (tree);
126 static int alter_access (tree, tree, tree);
127 static void handle_using_decl (tree, tree);
128 static tree dfs_modify_vtables (tree, void *);
129 static tree modify_all_vtables (tree, tree);
130 static void determine_primary_bases (tree);
131 static void finish_struct_methods (tree);
132 static void maybe_warn_about_overly_private_class (tree);
133 static int method_name_cmp (const void *, const void *);
134 static int resort_method_name_cmp (const void *, const void *);
135 static void add_implicitly_declared_members (tree, int, int);
136 static tree fixed_type_or_null (tree, int *, int *);
137 static tree build_simple_base_path (tree expr, tree binfo);
138 static tree build_vtbl_ref_1 (tree, tree);
139 static tree build_vtbl_initializer (tree, tree, tree, tree, int *);
140 static int count_fields (tree);
141 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
142 static bool check_bitfield_decl (tree);
143 static void check_field_decl (tree, tree, int *, int *, int *);
144 static void check_field_decls (tree, tree *, int *, int *);
145 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
146 static void build_base_fields (record_layout_info, splay_tree, tree *);
147 static void check_methods (tree);
148 static void remove_zero_width_bit_fields (tree);
149 static void check_bases (tree, int *, int *);
150 static void check_bases_and_members (tree);
151 static tree create_vtable_ptr (tree, tree *);
152 static void include_empty_classes (record_layout_info);
153 static void layout_class_type (tree, tree *);
154 static void propagate_binfo_offsets (tree, tree);
155 static void layout_virtual_bases (record_layout_info, splay_tree);
156 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
157 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
158 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
159 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
160 static void add_vcall_offset (tree, tree, vtbl_init_data *);
161 static void layout_vtable_decl (tree, int);
162 static tree dfs_find_final_overrider_pre (tree, void *);
163 static tree dfs_find_final_overrider_post (tree, void *);
164 static tree find_final_overrider (tree, tree, tree);
165 static int make_new_vtable (tree, tree);
166 static tree get_primary_binfo (tree);
167 static int maybe_indent_hierarchy (FILE *, int, int);
168 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
169 static void dump_class_hierarchy (tree);
170 static void dump_class_hierarchy_1 (FILE *, int, tree);
171 static void dump_array (FILE *, tree);
172 static void dump_vtable (tree, tree, tree);
173 static void dump_vtt (tree, tree);
174 static void dump_thunk (FILE *, int, tree);
175 static tree build_vtable (tree, tree, tree);
176 static void initialize_vtable (tree, tree);
177 static void layout_nonempty_base_or_field (record_layout_info,
178 tree, tree, splay_tree);
179 static tree end_of_class (tree, int);
180 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
181 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree);
182 static tree dfs_accumulate_vtbl_inits (tree, tree, tree, tree,
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 tree *build_vtt_inits (tree, tree, tree *, 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 offset = BINFO_OFFSET (binfo);
288 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
289 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
291 /* Do we need to look in the vtable for the real offset? */
292 virtual_access = (v_binfo && fixed_type_p <= 0);
294 /* Don't bother with the calculations inside sizeof; they'll ICE if the
295 source type is incomplete and the pointer value doesn't matter. */
296 if (cp_unevaluated_operand != 0)
298 expr = build_nop (build_pointer_type (target_type), expr);
300 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, NULL);
304 /* Do we need to check for a null pointer? */
305 if (want_pointer && !nonnull)
307 /* If we know the conversion will not actually change the value
308 of EXPR, then we can avoid testing the expression for NULL.
309 We have to avoid generating a COMPONENT_REF for a base class
310 field, because other parts of the compiler know that such
311 expressions are always non-NULL. */
312 if (!virtual_access && integer_zerop (offset))
315 /* TARGET_TYPE has been extracted from BINFO, and, is
316 therefore always cv-unqualified. Extract the
317 cv-qualifiers from EXPR so that the expression returned
318 matches the input. */
319 class_type = TREE_TYPE (TREE_TYPE (expr));
321 = cp_build_qualified_type (target_type,
322 cp_type_quals (class_type));
323 return build_nop (build_pointer_type (target_type), expr);
325 null_test = error_mark_node;
328 /* Protect against multiple evaluation if necessary. */
329 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
330 expr = save_expr (expr);
332 /* Now that we've saved expr, build the real null test. */
335 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
336 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
340 /* If this is a simple base reference, express it as a COMPONENT_REF. */
341 if (code == PLUS_EXPR && !virtual_access
342 /* We don't build base fields for empty bases, and they aren't very
343 interesting to the optimizers anyway. */
346 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
347 expr = build_simple_base_path (expr, binfo);
349 expr = build_address (expr);
350 target_type = TREE_TYPE (expr);
356 /* Going via virtual base V_BINFO. We need the static offset
357 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
358 V_BINFO. That offset is an entry in D_BINFO's vtable. */
361 if (fixed_type_p < 0 && in_base_initializer)
363 /* In a base member initializer, we cannot rely on the
364 vtable being set up. We have to indirect via the
368 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
369 t = build_pointer_type (t);
370 v_offset = convert (t, current_vtt_parm);
371 v_offset = cp_build_indirect_ref (v_offset, NULL,
372 tf_warning_or_error);
375 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, NULL,
376 tf_warning_or_error),
377 TREE_TYPE (TREE_TYPE (expr)));
379 v_offset = build2 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
380 v_offset, fold_convert (sizetype, BINFO_VPTR_FIELD (v_binfo)));
381 v_offset = build1 (NOP_EXPR,
382 build_pointer_type (ptrdiff_type_node),
384 v_offset = cp_build_indirect_ref (v_offset, NULL, tf_warning_or_error);
385 TREE_CONSTANT (v_offset) = 1;
387 offset = convert_to_integer (ptrdiff_type_node,
388 size_diffop_loc (input_location, offset,
389 BINFO_OFFSET (v_binfo)));
391 if (!integer_zerop (offset))
392 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
394 if (fixed_type_p < 0)
395 /* Negative fixed_type_p means this is a constructor or destructor;
396 virtual base layout is fixed in in-charge [cd]tors, but not in
398 offset = build3 (COND_EXPR, ptrdiff_type_node,
399 build2 (EQ_EXPR, boolean_type_node,
400 current_in_charge_parm, integer_zero_node),
402 convert_to_integer (ptrdiff_type_node,
403 BINFO_OFFSET (binfo)));
408 target_type = cp_build_qualified_type
409 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
410 ptr_target_type = build_pointer_type (target_type);
412 target_type = ptr_target_type;
414 expr = build1 (NOP_EXPR, ptr_target_type, expr);
416 if (!integer_zerop (offset))
418 offset = fold_convert (sizetype, offset);
419 if (code == MINUS_EXPR)
420 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
421 expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
427 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
431 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
432 fold_build1_loc (input_location, NOP_EXPR, target_type,
438 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
439 Perform a derived-to-base conversion by recursively building up a
440 sequence of COMPONENT_REFs to the appropriate base fields. */
443 build_simple_base_path (tree expr, tree binfo)
445 tree type = BINFO_TYPE (binfo);
446 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
449 if (d_binfo == NULL_TREE)
453 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
455 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
456 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
457 an lvalue in the front end; only _DECLs and _REFs are lvalues
459 temp = unary_complex_lvalue (ADDR_EXPR, expr);
461 expr = cp_build_indirect_ref (temp, NULL, tf_warning_or_error);
467 expr = build_simple_base_path (expr, d_binfo);
469 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
470 field; field = TREE_CHAIN (field))
471 /* Is this the base field created by build_base_field? */
472 if (TREE_CODE (field) == FIELD_DECL
473 && DECL_FIELD_IS_BASE (field)
474 && TREE_TYPE (field) == type)
476 /* We don't use build_class_member_access_expr here, as that
477 has unnecessary checks, and more importantly results in
478 recursive calls to dfs_walk_once. */
479 int type_quals = cp_type_quals (TREE_TYPE (expr));
481 expr = build3 (COMPONENT_REF,
482 cp_build_qualified_type (type, type_quals),
483 expr, field, NULL_TREE);
484 expr = fold_if_not_in_template (expr);
486 /* Mark the expression const or volatile, as appropriate.
487 Even though we've dealt with the type above, we still have
488 to mark the expression itself. */
489 if (type_quals & TYPE_QUAL_CONST)
490 TREE_READONLY (expr) = 1;
491 if (type_quals & TYPE_QUAL_VOLATILE)
492 TREE_THIS_VOLATILE (expr) = 1;
497 /* Didn't find the base field?!? */
501 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
502 type is a class type or a pointer to a class type. In the former
503 case, TYPE is also a class type; in the latter it is another
504 pointer type. If CHECK_ACCESS is true, an error message is emitted
505 if TYPE is inaccessible. If OBJECT has pointer type, the value is
506 assumed to be non-NULL. */
509 convert_to_base (tree object, tree type, bool check_access, bool nonnull)
514 if (TYPE_PTR_P (TREE_TYPE (object)))
516 object_type = TREE_TYPE (TREE_TYPE (object));
517 type = TREE_TYPE (type);
520 object_type = TREE_TYPE (object);
522 binfo = lookup_base (object_type, type,
523 check_access ? ba_check : ba_unique,
525 if (!binfo || binfo == error_mark_node)
526 return error_mark_node;
528 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
531 /* EXPR is an expression with unqualified class type. BASE is a base
532 binfo of that class type. Returns EXPR, converted to the BASE
533 type. This function assumes that EXPR is the most derived class;
534 therefore virtual bases can be found at their static offsets. */
537 convert_to_base_statically (tree expr, tree base)
541 expr_type = TREE_TYPE (expr);
542 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
546 pointer_type = build_pointer_type (expr_type);
548 /* We use fold_build2 and fold_convert below to simplify the trees
549 provided to the optimizers. It is not safe to call these functions
550 when processing a template because they do not handle C++-specific
552 gcc_assert (!processing_template_decl);
553 expr = cp_build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1,
554 tf_warning_or_error);
555 if (!integer_zerop (BINFO_OFFSET (base)))
556 expr = fold_build2_loc (input_location,
557 POINTER_PLUS_EXPR, pointer_type, expr,
558 fold_convert (sizetype, BINFO_OFFSET (base)));
559 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
560 expr = build_fold_indirect_ref_loc (input_location, expr);
568 build_vfield_ref (tree datum, tree type)
570 tree vfield, vcontext;
572 if (datum == error_mark_node)
573 return error_mark_node;
575 /* First, convert to the requested type. */
576 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
577 datum = convert_to_base (datum, type, /*check_access=*/false,
580 /* Second, the requested type may not be the owner of its own vptr.
581 If not, convert to the base class that owns it. We cannot use
582 convert_to_base here, because VCONTEXT may appear more than once
583 in the inheritance hierarchy of TYPE, and thus direct conversion
584 between the types may be ambiguous. Following the path back up
585 one step at a time via primary bases avoids the problem. */
586 vfield = TYPE_VFIELD (type);
587 vcontext = DECL_CONTEXT (vfield);
588 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
590 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
591 type = TREE_TYPE (datum);
594 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
597 /* Given an object INSTANCE, return an expression which yields the
598 vtable element corresponding to INDEX. There are many special
599 cases for INSTANCE which we take care of here, mainly to avoid
600 creating extra tree nodes when we don't have to. */
603 build_vtbl_ref_1 (tree instance, tree idx)
606 tree vtbl = NULL_TREE;
608 /* Try to figure out what a reference refers to, and
609 access its virtual function table directly. */
612 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
614 tree basetype = non_reference (TREE_TYPE (instance));
616 if (fixed_type && !cdtorp)
618 tree binfo = lookup_base (fixed_type, basetype,
619 ba_unique | ba_quiet, NULL);
621 vtbl = unshare_expr (BINFO_VTABLE (binfo));
625 vtbl = build_vfield_ref (instance, basetype);
628 aref = build_array_ref (input_location, vtbl, idx);
629 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
635 build_vtbl_ref (tree instance, tree idx)
637 tree aref = build_vtbl_ref_1 (instance, idx);
642 /* Given a stable object pointer INSTANCE_PTR, return an expression which
643 yields a function pointer corresponding to vtable element INDEX. */
646 build_vfn_ref (tree instance_ptr, tree idx)
650 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, 0,
651 tf_warning_or_error),
654 /* When using function descriptors, the address of the
655 vtable entry is treated as a function pointer. */
656 if (TARGET_VTABLE_USES_DESCRIPTORS)
657 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
658 cp_build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1,
659 tf_warning_or_error));
661 /* Remember this as a method reference, for later devirtualization. */
662 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
667 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
668 for the given TYPE. */
671 get_vtable_name (tree type)
673 return mangle_vtbl_for_type (type);
676 /* DECL is an entity associated with TYPE, like a virtual table or an
677 implicitly generated constructor. Determine whether or not DECL
678 should have external or internal linkage at the object file
679 level. This routine does not deal with COMDAT linkage and other
680 similar complexities; it simply sets TREE_PUBLIC if it possible for
681 entities in other translation units to contain copies of DECL, in
685 set_linkage_according_to_type (tree type, tree decl)
687 /* If TYPE involves a local class in a function with internal
688 linkage, then DECL should have internal linkage too. Other local
689 classes have no linkage -- but if their containing functions
690 have external linkage, it makes sense for DECL to have external
691 linkage too. That will allow template definitions to be merged,
693 if (no_linkage_check (type, /*relaxed_p=*/true))
695 TREE_PUBLIC (decl) = 0;
696 DECL_INTERFACE_KNOWN (decl) = 1;
699 TREE_PUBLIC (decl) = 1;
702 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
703 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
704 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
707 build_vtable (tree class_type, tree name, tree vtable_type)
711 decl = build_lang_decl (VAR_DECL, name, vtable_type);
712 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
713 now to avoid confusion in mangle_decl. */
714 SET_DECL_ASSEMBLER_NAME (decl, name);
715 DECL_CONTEXT (decl) = class_type;
716 DECL_ARTIFICIAL (decl) = 1;
717 TREE_STATIC (decl) = 1;
718 TREE_READONLY (decl) = 1;
719 DECL_VIRTUAL_P (decl) = 1;
720 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
721 DECL_VTABLE_OR_VTT_P (decl) = 1;
722 /* At one time the vtable info was grabbed 2 words at a time. This
723 fails on sparc unless you have 8-byte alignment. (tiemann) */
724 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
726 set_linkage_according_to_type (class_type, decl);
727 /* The vtable has not been defined -- yet. */
728 DECL_EXTERNAL (decl) = 1;
729 DECL_NOT_REALLY_EXTERN (decl) = 1;
731 /* Mark the VAR_DECL node representing the vtable itself as a
732 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
733 is rather important that such things be ignored because any
734 effort to actually generate DWARF for them will run into
735 trouble when/if we encounter code like:
738 struct S { virtual void member (); };
740 because the artificial declaration of the vtable itself (as
741 manufactured by the g++ front end) will say that the vtable is
742 a static member of `S' but only *after* the debug output for
743 the definition of `S' has already been output. This causes
744 grief because the DWARF entry for the definition of the vtable
745 will try to refer back to an earlier *declaration* of the
746 vtable as a static member of `S' and there won't be one. We
747 might be able to arrange to have the "vtable static member"
748 attached to the member list for `S' before the debug info for
749 `S' get written (which would solve the problem) but that would
750 require more intrusive changes to the g++ front end. */
751 DECL_IGNORED_P (decl) = 1;
756 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
757 or even complete. If this does not exist, create it. If COMPLETE is
758 nonzero, then complete the definition of it -- that will render it
759 impossible to actually build the vtable, but is useful to get at those
760 which are known to exist in the runtime. */
763 get_vtable_decl (tree type, int complete)
767 if (CLASSTYPE_VTABLES (type))
768 return CLASSTYPE_VTABLES (type);
770 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
771 CLASSTYPE_VTABLES (type) = decl;
775 DECL_EXTERNAL (decl) = 1;
776 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
782 /* Build the primary virtual function table for TYPE. If BINFO is
783 non-NULL, build the vtable starting with the initial approximation
784 that it is the same as the one which is the head of the association
785 list. Returns a nonzero value if a new vtable is actually
789 build_primary_vtable (tree binfo, tree type)
794 decl = get_vtable_decl (type, /*complete=*/0);
798 if (BINFO_NEW_VTABLE_MARKED (binfo))
799 /* We have already created a vtable for this base, so there's
800 no need to do it again. */
803 virtuals = copy_list (BINFO_VIRTUALS (binfo));
804 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
805 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
806 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
810 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
811 virtuals = NULL_TREE;
814 #ifdef GATHER_STATISTICS
816 n_vtable_elems += list_length (virtuals);
819 /* Initialize the association list for this type, based
820 on our first approximation. */
821 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
822 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
823 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
827 /* Give BINFO a new virtual function table which is initialized
828 with a skeleton-copy of its original initialization. The only
829 entry that changes is the `delta' entry, so we can really
830 share a lot of structure.
832 FOR_TYPE is the most derived type which caused this table to
835 Returns nonzero if we haven't met BINFO before.
837 The order in which vtables are built (by calling this function) for
838 an object must remain the same, otherwise a binary incompatibility
842 build_secondary_vtable (tree binfo)
844 if (BINFO_NEW_VTABLE_MARKED (binfo))
845 /* We already created a vtable for this base. There's no need to
849 /* Remember that we've created a vtable for this BINFO, so that we
850 don't try to do so again. */
851 SET_BINFO_NEW_VTABLE_MARKED (binfo);
853 /* Make fresh virtual list, so we can smash it later. */
854 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
856 /* Secondary vtables are laid out as part of the same structure as
857 the primary vtable. */
858 BINFO_VTABLE (binfo) = NULL_TREE;
862 /* Create a new vtable for BINFO which is the hierarchy dominated by
863 T. Return nonzero if we actually created a new vtable. */
866 make_new_vtable (tree t, tree binfo)
868 if (binfo == TYPE_BINFO (t))
869 /* In this case, it is *type*'s vtable we are modifying. We start
870 with the approximation that its vtable is that of the
871 immediate base class. */
872 return build_primary_vtable (binfo, t);
874 /* This is our very own copy of `basetype' to play with. Later,
875 we will fill in all the virtual functions that override the
876 virtual functions in these base classes which are not defined
877 by the current type. */
878 return build_secondary_vtable (binfo);
881 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
882 (which is in the hierarchy dominated by T) list FNDECL as its
883 BV_FN. DELTA is the required constant adjustment from the `this'
884 pointer where the vtable entry appears to the `this' required when
885 the function is actually called. */
888 modify_vtable_entry (tree t,
898 if (fndecl != BV_FN (v)
899 || !tree_int_cst_equal (delta, BV_DELTA (v)))
901 /* We need a new vtable for BINFO. */
902 if (make_new_vtable (t, binfo))
904 /* If we really did make a new vtable, we also made a copy
905 of the BINFO_VIRTUALS list. Now, we have to find the
906 corresponding entry in that list. */
907 *virtuals = BINFO_VIRTUALS (binfo);
908 while (BV_FN (*virtuals) != BV_FN (v))
909 *virtuals = TREE_CHAIN (*virtuals);
913 BV_DELTA (v) = delta;
914 BV_VCALL_INDEX (v) = NULL_TREE;
920 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
921 the USING_DECL naming METHOD. Returns true if the method could be
922 added to the method vec. */
925 add_method (tree type, tree method, tree using_decl)
929 bool template_conv_p = false;
931 VEC(tree,gc) *method_vec;
933 bool insert_p = false;
937 if (method == error_mark_node)
940 complete_p = COMPLETE_TYPE_P (type);
941 conv_p = DECL_CONV_FN_P (method);
943 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
944 && DECL_TEMPLATE_CONV_FN_P (method));
946 method_vec = CLASSTYPE_METHOD_VEC (type);
949 /* Make a new method vector. We start with 8 entries. We must
950 allocate at least two (for constructors and destructors), and
951 we're going to end up with an assignment operator at some
953 method_vec = VEC_alloc (tree, gc, 8);
954 /* Create slots for constructors and destructors. */
955 VEC_quick_push (tree, method_vec, NULL_TREE);
956 VEC_quick_push (tree, method_vec, NULL_TREE);
957 CLASSTYPE_METHOD_VEC (type) = method_vec;
960 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
961 grok_special_member_properties (method);
963 /* Constructors and destructors go in special slots. */
964 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
965 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
966 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
968 slot = CLASSTYPE_DESTRUCTOR_SLOT;
970 if (TYPE_FOR_JAVA (type))
972 if (!DECL_ARTIFICIAL (method))
973 error ("Java class %qT cannot have a destructor", type);
974 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
975 error ("Java class %qT cannot have an implicit non-trivial "
985 /* See if we already have an entry with this name. */
986 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
987 VEC_iterate (tree, method_vec, slot, m);
993 if (TREE_CODE (m) == TEMPLATE_DECL
994 && DECL_TEMPLATE_CONV_FN_P (m))
998 if (conv_p && !DECL_CONV_FN_P (m))
1000 if (DECL_NAME (m) == DECL_NAME (method))
1006 && !DECL_CONV_FN_P (m)
1007 && DECL_NAME (m) > DECL_NAME (method))
1011 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1013 /* Check to see if we've already got this method. */
1014 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1016 tree fn = OVL_CURRENT (fns);
1022 if (TREE_CODE (fn) != TREE_CODE (method))
1025 /* [over.load] Member function declarations with the
1026 same name and the same parameter types cannot be
1027 overloaded if any of them is a static member
1028 function declaration.
1030 [namespace.udecl] When a using-declaration brings names
1031 from a base class into a derived class scope, member
1032 functions in the derived class override and/or hide member
1033 functions with the same name and parameter types in a base
1034 class (rather than conflicting). */
1035 fn_type = TREE_TYPE (fn);
1036 method_type = TREE_TYPE (method);
1037 parms1 = TYPE_ARG_TYPES (fn_type);
1038 parms2 = TYPE_ARG_TYPES (method_type);
1040 /* Compare the quals on the 'this' parm. Don't compare
1041 the whole types, as used functions are treated as
1042 coming from the using class in overload resolution. */
1043 if (! DECL_STATIC_FUNCTION_P (fn)
1044 && ! DECL_STATIC_FUNCTION_P (method)
1045 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1046 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1047 && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
1048 != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
1051 /* For templates, the return type and template parameters
1052 must be identical. */
1053 if (TREE_CODE (fn) == TEMPLATE_DECL
1054 && (!same_type_p (TREE_TYPE (fn_type),
1055 TREE_TYPE (method_type))
1056 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1057 DECL_TEMPLATE_PARMS (method))))
1060 if (! DECL_STATIC_FUNCTION_P (fn))
1061 parms1 = TREE_CHAIN (parms1);
1062 if (! DECL_STATIC_FUNCTION_P (method))
1063 parms2 = TREE_CHAIN (parms2);
1065 if (compparms (parms1, parms2)
1066 && (!DECL_CONV_FN_P (fn)
1067 || same_type_p (TREE_TYPE (fn_type),
1068 TREE_TYPE (method_type))))
1072 if (DECL_CONTEXT (fn) == type)
1073 /* Defer to the local function. */
1075 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1076 error ("repeated using declaration %q+D", using_decl);
1078 error ("using declaration %q+D conflicts with a previous using declaration",
1083 error ("%q+#D cannot be overloaded", method);
1084 error ("with %q+#D", fn);
1087 /* We don't call duplicate_decls here to merge the
1088 declarations because that will confuse things if the
1089 methods have inline definitions. In particular, we
1090 will crash while processing the definitions. */
1095 /* A class should never have more than one destructor. */
1096 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1099 /* Add the new binding. */
1100 overload = build_overload (method, current_fns);
1103 TYPE_HAS_CONVERSION (type) = 1;
1104 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1105 push_class_level_binding (DECL_NAME (method), overload);
1111 /* We only expect to add few methods in the COMPLETE_P case, so
1112 just make room for one more method in that case. */
1114 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1116 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1118 CLASSTYPE_METHOD_VEC (type) = method_vec;
1119 if (slot == VEC_length (tree, method_vec))
1120 VEC_quick_push (tree, method_vec, overload);
1122 VEC_quick_insert (tree, method_vec, slot, overload);
1125 /* Replace the current slot. */
1126 VEC_replace (tree, method_vec, slot, overload);
1130 /* Subroutines of finish_struct. */
1132 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1133 legit, otherwise return 0. */
1136 alter_access (tree t, tree fdecl, tree access)
1140 if (!DECL_LANG_SPECIFIC (fdecl))
1141 retrofit_lang_decl (fdecl);
1143 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1145 elem = purpose_member (t, DECL_ACCESS (fdecl));
1148 if (TREE_VALUE (elem) != access)
1150 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1151 error ("conflicting access specifications for method"
1152 " %q+D, ignored", TREE_TYPE (fdecl));
1154 error ("conflicting access specifications for field %qE, ignored",
1159 /* They're changing the access to the same thing they changed
1160 it to before. That's OK. */
1166 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1167 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1173 /* Process the USING_DECL, which is a member of T. */
1176 handle_using_decl (tree using_decl, tree t)
1178 tree decl = USING_DECL_DECLS (using_decl);
1179 tree name = DECL_NAME (using_decl);
1181 = TREE_PRIVATE (using_decl) ? access_private_node
1182 : TREE_PROTECTED (using_decl) ? access_protected_node
1183 : access_public_node;
1184 tree flist = NULL_TREE;
1187 gcc_assert (!processing_template_decl && decl);
1189 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1192 if (is_overloaded_fn (old_value))
1193 old_value = OVL_CURRENT (old_value);
1195 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1198 old_value = NULL_TREE;
1201 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1203 if (is_overloaded_fn (decl))
1208 else if (is_overloaded_fn (old_value))
1211 /* It's OK to use functions from a base when there are functions with
1212 the same name already present in the current class. */;
1215 error ("%q+D invalid in %q#T", using_decl, t);
1216 error (" because of local method %q+#D with same name",
1217 OVL_CURRENT (old_value));
1221 else if (!DECL_ARTIFICIAL (old_value))
1223 error ("%q+D invalid in %q#T", using_decl, t);
1224 error (" because of local member %q+#D with same name", old_value);
1228 /* Make type T see field decl FDECL with access ACCESS. */
1230 for (; flist; flist = OVL_NEXT (flist))
1232 add_method (t, OVL_CURRENT (flist), using_decl);
1233 alter_access (t, OVL_CURRENT (flist), access);
1236 alter_access (t, decl, access);
1239 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1240 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1241 properties of the bases. */
1244 check_bases (tree t,
1245 int* cant_have_const_ctor_p,
1246 int* no_const_asn_ref_p)
1249 int seen_non_virtual_nearly_empty_base_p;
1252 tree field = NULL_TREE;
1254 seen_non_virtual_nearly_empty_base_p = 0;
1256 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1257 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1258 if (TREE_CODE (field) == FIELD_DECL)
1261 for (binfo = TYPE_BINFO (t), i = 0;
1262 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1264 tree basetype = TREE_TYPE (base_binfo);
1266 gcc_assert (COMPLETE_TYPE_P (basetype));
1268 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1269 here because the case of virtual functions but non-virtual
1270 dtor is handled in finish_struct_1. */
1271 if (!TYPE_POLYMORPHIC_P (basetype))
1272 warning (OPT_Weffc__,
1273 "base class %q#T has a non-virtual destructor", basetype);
1275 /* If the base class doesn't have copy constructors or
1276 assignment operators that take const references, then the
1277 derived class cannot have such a member automatically
1279 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1280 *cant_have_const_ctor_p = 1;
1281 if (TYPE_HAS_ASSIGN_REF (basetype)
1282 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1283 *no_const_asn_ref_p = 1;
1285 if (BINFO_VIRTUAL_P (base_binfo))
1286 /* A virtual base does not effect nearly emptiness. */
1288 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1290 if (seen_non_virtual_nearly_empty_base_p)
1291 /* And if there is more than one nearly empty base, then the
1292 derived class is not nearly empty either. */
1293 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1295 /* Remember we've seen one. */
1296 seen_non_virtual_nearly_empty_base_p = 1;
1298 else if (!is_empty_class (basetype))
1299 /* If the base class is not empty or nearly empty, then this
1300 class cannot be nearly empty. */
1301 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1303 /* A lot of properties from the bases also apply to the derived
1305 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1306 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1307 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1308 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1309 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1310 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1311 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1312 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1313 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1314 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (basetype);
1316 /* A standard-layout class is a class that:
1318 * has no non-standard-layout base classes, */
1319 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1320 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1323 /* ...has no base classes of the same type as the first non-static
1325 if (field && DECL_CONTEXT (field) == t
1326 && (same_type_ignoring_top_level_qualifiers_p
1327 (TREE_TYPE (field), basetype)))
1328 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1330 /* ...either has no non-static data members in the most-derived
1331 class and at most one base class with non-static data
1332 members, or has no base classes with non-static data
1334 for (basefield = TYPE_FIELDS (basetype); basefield;
1335 basefield = TREE_CHAIN (basefield))
1336 if (TREE_CODE (basefield) == FIELD_DECL)
1339 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1348 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1349 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1350 that have had a nearly-empty virtual primary base stolen by some
1351 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1355 determine_primary_bases (tree t)
1358 tree primary = NULL_TREE;
1359 tree type_binfo = TYPE_BINFO (t);
1362 /* Determine the primary bases of our bases. */
1363 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1364 base_binfo = TREE_CHAIN (base_binfo))
1366 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1368 /* See if we're the non-virtual primary of our inheritance
1370 if (!BINFO_VIRTUAL_P (base_binfo))
1372 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1373 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1376 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1377 BINFO_TYPE (parent_primary)))
1378 /* We are the primary binfo. */
1379 BINFO_PRIMARY_P (base_binfo) = 1;
1381 /* Determine if we have a virtual primary base, and mark it so.
1383 if (primary && BINFO_VIRTUAL_P (primary))
1385 tree this_primary = copied_binfo (primary, base_binfo);
1387 if (BINFO_PRIMARY_P (this_primary))
1388 /* Someone already claimed this base. */
1389 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1394 BINFO_PRIMARY_P (this_primary) = 1;
1395 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1397 /* A virtual binfo might have been copied from within
1398 another hierarchy. As we're about to use it as a
1399 primary base, make sure the offsets match. */
1400 delta = size_diffop_loc (input_location,
1402 BINFO_OFFSET (base_binfo)),
1404 BINFO_OFFSET (this_primary)));
1406 propagate_binfo_offsets (this_primary, delta);
1411 /* First look for a dynamic direct non-virtual base. */
1412 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1414 tree basetype = BINFO_TYPE (base_binfo);
1416 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1418 primary = base_binfo;
1423 /* A "nearly-empty" virtual base class can be the primary base
1424 class, if no non-virtual polymorphic base can be found. Look for
1425 a nearly-empty virtual dynamic base that is not already a primary
1426 base of something in the hierarchy. If there is no such base,
1427 just pick the first nearly-empty virtual base. */
1429 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1430 base_binfo = TREE_CHAIN (base_binfo))
1431 if (BINFO_VIRTUAL_P (base_binfo)
1432 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1434 if (!BINFO_PRIMARY_P (base_binfo))
1436 /* Found one that is not primary. */
1437 primary = base_binfo;
1441 /* Remember the first candidate. */
1442 primary = base_binfo;
1446 /* If we've got a primary base, use it. */
1449 tree basetype = BINFO_TYPE (primary);
1451 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1452 if (BINFO_PRIMARY_P (primary))
1453 /* We are stealing a primary base. */
1454 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1455 BINFO_PRIMARY_P (primary) = 1;
1456 if (BINFO_VIRTUAL_P (primary))
1460 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1461 /* A virtual binfo might have been copied from within
1462 another hierarchy. As we're about to use it as a primary
1463 base, make sure the offsets match. */
1464 delta = size_diffop_loc (input_location, ssize_int (0),
1465 convert (ssizetype, BINFO_OFFSET (primary)));
1467 propagate_binfo_offsets (primary, delta);
1470 primary = TYPE_BINFO (basetype);
1472 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1473 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1474 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1478 /* Update the variant types of T. */
1481 fixup_type_variants (tree t)
1488 for (variants = TYPE_NEXT_VARIANT (t);
1490 variants = TYPE_NEXT_VARIANT (variants))
1492 /* These fields are in the _TYPE part of the node, not in
1493 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1494 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1495 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1496 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1497 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1499 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1501 TYPE_BINFO (variants) = TYPE_BINFO (t);
1503 /* Copy whatever these are holding today. */
1504 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1505 TYPE_METHODS (variants) = TYPE_METHODS (t);
1506 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1508 /* All variants of a class have the same attributes. */
1509 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1514 /* Set memoizing fields and bits of T (and its variants) for later
1518 finish_struct_bits (tree t)
1520 /* Fix up variants (if any). */
1521 fixup_type_variants (t);
1523 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1524 /* For a class w/o baseclasses, 'finish_struct' has set
1525 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1526 Similarly for a class whose base classes do not have vtables.
1527 When neither of these is true, we might have removed abstract
1528 virtuals (by providing a definition), added some (by declaring
1529 new ones), or redeclared ones from a base class. We need to
1530 recalculate what's really an abstract virtual at this point (by
1531 looking in the vtables). */
1532 get_pure_virtuals (t);
1534 /* If this type has a copy constructor or a destructor, force its
1535 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1536 nonzero. This will cause it to be passed by invisible reference
1537 and prevent it from being returned in a register. */
1538 if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1541 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1542 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1544 SET_TYPE_MODE (variants, BLKmode);
1545 TREE_ADDRESSABLE (variants) = 1;
1550 /* Issue warnings about T having private constructors, but no friends,
1553 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1554 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1555 non-private static member functions. */
1558 maybe_warn_about_overly_private_class (tree t)
1560 int has_member_fn = 0;
1561 int has_nonprivate_method = 0;
1564 if (!warn_ctor_dtor_privacy
1565 /* If the class has friends, those entities might create and
1566 access instances, so we should not warn. */
1567 || (CLASSTYPE_FRIEND_CLASSES (t)
1568 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1569 /* We will have warned when the template was declared; there's
1570 no need to warn on every instantiation. */
1571 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1572 /* There's no reason to even consider warning about this
1576 /* We only issue one warning, if more than one applies, because
1577 otherwise, on code like:
1580 // Oops - forgot `public:'
1586 we warn several times about essentially the same problem. */
1588 /* Check to see if all (non-constructor, non-destructor) member
1589 functions are private. (Since there are no friends or
1590 non-private statics, we can't ever call any of the private member
1592 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1593 /* We're not interested in compiler-generated methods; they don't
1594 provide any way to call private members. */
1595 if (!DECL_ARTIFICIAL (fn))
1597 if (!TREE_PRIVATE (fn))
1599 if (DECL_STATIC_FUNCTION_P (fn))
1600 /* A non-private static member function is just like a
1601 friend; it can create and invoke private member
1602 functions, and be accessed without a class
1606 has_nonprivate_method = 1;
1607 /* Keep searching for a static member function. */
1609 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1613 if (!has_nonprivate_method && has_member_fn)
1615 /* There are no non-private methods, and there's at least one
1616 private member function that isn't a constructor or
1617 destructor. (If all the private members are
1618 constructors/destructors we want to use the code below that
1619 issues error messages specifically referring to
1620 constructors/destructors.) */
1622 tree binfo = TYPE_BINFO (t);
1624 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1625 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1627 has_nonprivate_method = 1;
1630 if (!has_nonprivate_method)
1632 warning (OPT_Wctor_dtor_privacy,
1633 "all member functions in class %qT are private", t);
1638 /* Even if some of the member functions are non-private, the class
1639 won't be useful for much if all the constructors or destructors
1640 are private: such an object can never be created or destroyed. */
1641 fn = CLASSTYPE_DESTRUCTORS (t);
1642 if (fn && TREE_PRIVATE (fn))
1644 warning (OPT_Wctor_dtor_privacy,
1645 "%q#T only defines a private destructor and has no friends",
1650 /* Warn about classes that have private constructors and no friends. */
1651 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1652 /* Implicitly generated constructors are always public. */
1653 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1654 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1656 int nonprivate_ctor = 0;
1658 /* If a non-template class does not define a copy
1659 constructor, one is defined for it, enabling it to avoid
1660 this warning. For a template class, this does not
1661 happen, and so we would normally get a warning on:
1663 template <class T> class C { private: C(); };
1665 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1666 complete non-template or fully instantiated classes have this
1668 if (!TYPE_HAS_INIT_REF (t))
1669 nonprivate_ctor = 1;
1671 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1673 tree ctor = OVL_CURRENT (fn);
1674 /* Ideally, we wouldn't count copy constructors (or, in
1675 fact, any constructor that takes an argument of the
1676 class type as a parameter) because such things cannot
1677 be used to construct an instance of the class unless
1678 you already have one. But, for now at least, we're
1680 if (! TREE_PRIVATE (ctor))
1682 nonprivate_ctor = 1;
1687 if (nonprivate_ctor == 0)
1689 warning (OPT_Wctor_dtor_privacy,
1690 "%q#T only defines private constructors and has no friends",
1698 gt_pointer_operator new_value;
1702 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1705 method_name_cmp (const void* m1_p, const void* m2_p)
1707 const tree *const m1 = (const tree *) m1_p;
1708 const tree *const m2 = (const tree *) m2_p;
1710 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1712 if (*m1 == NULL_TREE)
1714 if (*m2 == NULL_TREE)
1716 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1721 /* This routine compares two fields like method_name_cmp but using the
1722 pointer operator in resort_field_decl_data. */
1725 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1727 const tree *const m1 = (const tree *) m1_p;
1728 const tree *const m2 = (const tree *) m2_p;
1729 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1731 if (*m1 == NULL_TREE)
1733 if (*m2 == NULL_TREE)
1736 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1737 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1738 resort_data.new_value (&d1, resort_data.cookie);
1739 resort_data.new_value (&d2, resort_data.cookie);
1746 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1749 resort_type_method_vec (void* obj,
1750 void* orig_obj ATTRIBUTE_UNUSED ,
1751 gt_pointer_operator new_value,
1754 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1755 int len = VEC_length (tree, method_vec);
1759 /* The type conversion ops have to live at the front of the vec, so we
1761 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1762 VEC_iterate (tree, method_vec, slot, fn);
1764 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1769 resort_data.new_value = new_value;
1770 resort_data.cookie = cookie;
1771 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1772 resort_method_name_cmp);
1776 /* Warn about duplicate methods in fn_fields.
1778 Sort methods that are not special (i.e., constructors, destructors,
1779 and type conversion operators) so that we can find them faster in
1783 finish_struct_methods (tree t)
1786 VEC(tree,gc) *method_vec;
1789 method_vec = CLASSTYPE_METHOD_VEC (t);
1793 len = VEC_length (tree, method_vec);
1795 /* Clear DECL_IN_AGGR_P for all functions. */
1796 for (fn_fields = TYPE_METHODS (t); fn_fields;
1797 fn_fields = TREE_CHAIN (fn_fields))
1798 DECL_IN_AGGR_P (fn_fields) = 0;
1800 /* Issue warnings about private constructors and such. If there are
1801 no methods, then some public defaults are generated. */
1802 maybe_warn_about_overly_private_class (t);
1804 /* The type conversion ops have to live at the front of the vec, so we
1806 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1807 VEC_iterate (tree, method_vec, slot, fn_fields);
1809 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1812 qsort (VEC_address (tree, method_vec) + slot,
1813 len-slot, sizeof (tree), method_name_cmp);
1816 /* Make BINFO's vtable have N entries, including RTTI entries,
1817 vbase and vcall offsets, etc. Set its type and call the back end
1821 layout_vtable_decl (tree binfo, int n)
1826 atype = build_cplus_array_type (vtable_entry_type,
1827 build_index_type (size_int (n - 1)));
1828 layout_type (atype);
1830 /* We may have to grow the vtable. */
1831 vtable = get_vtbl_decl_for_binfo (binfo);
1832 if (!same_type_p (TREE_TYPE (vtable), atype))
1834 TREE_TYPE (vtable) = atype;
1835 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1836 layout_decl (vtable, 0);
1840 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1841 have the same signature. */
1844 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1846 /* One destructor overrides another if they are the same kind of
1848 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1849 && special_function_p (base_fndecl) == special_function_p (fndecl))
1851 /* But a non-destructor never overrides a destructor, nor vice
1852 versa, nor do different kinds of destructors override
1853 one-another. For example, a complete object destructor does not
1854 override a deleting destructor. */
1855 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1858 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1859 || (DECL_CONV_FN_P (fndecl)
1860 && DECL_CONV_FN_P (base_fndecl)
1861 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1862 DECL_CONV_FN_TYPE (base_fndecl))))
1864 tree types, base_types;
1865 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1866 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1867 if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1868 == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1869 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1875 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1879 base_derived_from (tree derived, tree base)
1883 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1885 if (probe == derived)
1887 else if (BINFO_VIRTUAL_P (probe))
1888 /* If we meet a virtual base, we can't follow the inheritance
1889 any more. See if the complete type of DERIVED contains
1890 such a virtual base. */
1891 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1897 typedef struct find_final_overrider_data_s {
1898 /* The function for which we are trying to find a final overrider. */
1900 /* The base class in which the function was declared. */
1901 tree declaring_base;
1902 /* The candidate overriders. */
1904 /* Path to most derived. */
1905 VEC(tree,heap) *path;
1906 } find_final_overrider_data;
1908 /* Add the overrider along the current path to FFOD->CANDIDATES.
1909 Returns true if an overrider was found; false otherwise. */
1912 dfs_find_final_overrider_1 (tree binfo,
1913 find_final_overrider_data *ffod,
1918 /* If BINFO is not the most derived type, try a more derived class.
1919 A definition there will overrider a definition here. */
1923 if (dfs_find_final_overrider_1
1924 (VEC_index (tree, ffod->path, depth), ffod, depth))
1928 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1931 tree *candidate = &ffod->candidates;
1933 /* Remove any candidates overridden by this new function. */
1936 /* If *CANDIDATE overrides METHOD, then METHOD
1937 cannot override anything else on the list. */
1938 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1940 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1941 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1942 *candidate = TREE_CHAIN (*candidate);
1944 candidate = &TREE_CHAIN (*candidate);
1947 /* Add the new function. */
1948 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1955 /* Called from find_final_overrider via dfs_walk. */
1958 dfs_find_final_overrider_pre (tree binfo, void *data)
1960 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1962 if (binfo == ffod->declaring_base)
1963 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1964 VEC_safe_push (tree, heap, ffod->path, binfo);
1970 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1972 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1973 VEC_pop (tree, ffod->path);
1978 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1979 FN and whose TREE_VALUE is the binfo for the base where the
1980 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1981 DERIVED) is the base object in which FN is declared. */
1984 find_final_overrider (tree derived, tree binfo, tree fn)
1986 find_final_overrider_data ffod;
1988 /* Getting this right is a little tricky. This is valid:
1990 struct S { virtual void f (); };
1991 struct T { virtual void f (); };
1992 struct U : public S, public T { };
1994 even though calling `f' in `U' is ambiguous. But,
1996 struct R { virtual void f(); };
1997 struct S : virtual public R { virtual void f (); };
1998 struct T : virtual public R { virtual void f (); };
1999 struct U : public S, public T { };
2001 is not -- there's no way to decide whether to put `S::f' or
2002 `T::f' in the vtable for `R'.
2004 The solution is to look at all paths to BINFO. If we find
2005 different overriders along any two, then there is a problem. */
2006 if (DECL_THUNK_P (fn))
2007 fn = THUNK_TARGET (fn);
2009 /* Determine the depth of the hierarchy. */
2011 ffod.declaring_base = binfo;
2012 ffod.candidates = NULL_TREE;
2013 ffod.path = VEC_alloc (tree, heap, 30);
2015 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2016 dfs_find_final_overrider_post, &ffod);
2018 VEC_free (tree, heap, ffod.path);
2020 /* If there was no winner, issue an error message. */
2021 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2022 return error_mark_node;
2024 return ffod.candidates;
2027 /* Return the index of the vcall offset for FN when TYPE is used as a
2031 get_vcall_index (tree fn, tree type)
2033 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2037 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
2038 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2039 || same_signature_p (fn, p->purpose))
2042 /* There should always be an appropriate index. */
2046 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2047 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
2048 corresponding position in the BINFO_VIRTUALS list. */
2051 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2059 tree overrider_fn, overrider_target;
2060 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2061 tree over_return, base_return;
2064 /* Find the nearest primary base (possibly binfo itself) which defines
2065 this function; this is the class the caller will convert to when
2066 calling FN through BINFO. */
2067 for (b = binfo; ; b = get_primary_binfo (b))
2070 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2073 /* The nearest definition is from a lost primary. */
2074 if (BINFO_LOST_PRIMARY_P (b))
2079 /* Find the final overrider. */
2080 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2081 if (overrider == error_mark_node)
2083 error ("no unique final overrider for %qD in %qT", target_fn, t);
2086 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2088 /* Check for adjusting covariant return types. */
2089 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2090 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2092 if (POINTER_TYPE_P (over_return)
2093 && TREE_CODE (over_return) == TREE_CODE (base_return)
2094 && CLASS_TYPE_P (TREE_TYPE (over_return))
2095 && CLASS_TYPE_P (TREE_TYPE (base_return))
2096 /* If the overrider is invalid, don't even try. */
2097 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2099 /* If FN is a covariant thunk, we must figure out the adjustment
2100 to the final base FN was converting to. As OVERRIDER_TARGET might
2101 also be converting to the return type of FN, we have to
2102 combine the two conversions here. */
2103 tree fixed_offset, virtual_offset;
2105 over_return = TREE_TYPE (over_return);
2106 base_return = TREE_TYPE (base_return);
2108 if (DECL_THUNK_P (fn))
2110 gcc_assert (DECL_RESULT_THUNK_P (fn));
2111 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2112 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2115 fixed_offset = virtual_offset = NULL_TREE;
2118 /* Find the equivalent binfo within the return type of the
2119 overriding function. We will want the vbase offset from
2121 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2123 else if (!same_type_ignoring_top_level_qualifiers_p
2124 (over_return, base_return))
2126 /* There was no existing virtual thunk (which takes
2127 precedence). So find the binfo of the base function's
2128 return type within the overriding function's return type.
2129 We cannot call lookup base here, because we're inside a
2130 dfs_walk, and will therefore clobber the BINFO_MARKED
2131 flags. Fortunately we know the covariancy is valid (it
2132 has already been checked), so we can just iterate along
2133 the binfos, which have been chained in inheritance graph
2134 order. Of course it is lame that we have to repeat the
2135 search here anyway -- we should really be caching pieces
2136 of the vtable and avoiding this repeated work. */
2137 tree thunk_binfo, base_binfo;
2139 /* Find the base binfo within the overriding function's
2140 return type. We will always find a thunk_binfo, except
2141 when the covariancy is invalid (which we will have
2142 already diagnosed). */
2143 for (base_binfo = TYPE_BINFO (base_return),
2144 thunk_binfo = TYPE_BINFO (over_return);
2146 thunk_binfo = TREE_CHAIN (thunk_binfo))
2147 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2148 BINFO_TYPE (base_binfo)))
2151 /* See if virtual inheritance is involved. */
2152 for (virtual_offset = thunk_binfo;
2154 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2155 if (BINFO_VIRTUAL_P (virtual_offset))
2159 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2161 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2165 /* We convert via virtual base. Adjust the fixed
2166 offset to be from there. */
2168 size_diffop (offset,
2170 BINFO_OFFSET (virtual_offset)));
2173 /* There was an existing fixed offset, this must be
2174 from the base just converted to, and the base the
2175 FN was thunking to. */
2176 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2178 fixed_offset = offset;
2182 if (fixed_offset || virtual_offset)
2183 /* Replace the overriding function with a covariant thunk. We
2184 will emit the overriding function in its own slot as
2186 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2187 fixed_offset, virtual_offset);
2190 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2191 !DECL_THUNK_P (fn));
2193 /* Assume that we will produce a thunk that convert all the way to
2194 the final overrider, and not to an intermediate virtual base. */
2195 virtual_base = NULL_TREE;
2197 /* See if we can convert to an intermediate virtual base first, and then
2198 use the vcall offset located there to finish the conversion. */
2199 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2201 /* If we find the final overrider, then we can stop
2203 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2204 BINFO_TYPE (TREE_VALUE (overrider))))
2207 /* If we find a virtual base, and we haven't yet found the
2208 overrider, then there is a virtual base between the
2209 declaring base (first_defn) and the final overrider. */
2210 if (BINFO_VIRTUAL_P (b))
2217 if (overrider_fn != overrider_target && !virtual_base)
2219 /* The ABI specifies that a covariant thunk includes a mangling
2220 for a this pointer adjustment. This-adjusting thunks that
2221 override a function from a virtual base have a vcall
2222 adjustment. When the virtual base in question is a primary
2223 virtual base, we know the adjustments are zero, (and in the
2224 non-covariant case, we would not use the thunk).
2225 Unfortunately we didn't notice this could happen, when
2226 designing the ABI and so never mandated that such a covariant
2227 thunk should be emitted. Because we must use the ABI mandated
2228 name, we must continue searching from the binfo where we
2229 found the most recent definition of the function, towards the
2230 primary binfo which first introduced the function into the
2231 vtable. If that enters a virtual base, we must use a vcall
2232 this-adjusting thunk. Bleah! */
2233 tree probe = first_defn;
2235 while ((probe = get_primary_binfo (probe))
2236 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2237 if (BINFO_VIRTUAL_P (probe))
2238 virtual_base = probe;
2241 /* Even if we find a virtual base, the correct delta is
2242 between the overrider and the binfo we're building a vtable
2244 goto virtual_covariant;
2247 /* Compute the constant adjustment to the `this' pointer. The
2248 `this' pointer, when this function is called, will point at BINFO
2249 (or one of its primary bases, which are at the same offset). */
2251 /* The `this' pointer needs to be adjusted from the declaration to
2252 the nearest virtual base. */
2253 delta = size_diffop_loc (input_location,
2254 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2255 convert (ssizetype, BINFO_OFFSET (first_defn)));
2257 /* If the nearest definition is in a lost primary, we don't need an
2258 entry in our vtable. Except possibly in a constructor vtable,
2259 if we happen to get our primary back. In that case, the offset
2260 will be zero, as it will be a primary base. */
2261 delta = size_zero_node;
2263 /* The `this' pointer needs to be adjusted from pointing to
2264 BINFO to pointing at the base where the final overrider
2267 delta = size_diffop_loc (input_location,
2269 BINFO_OFFSET (TREE_VALUE (overrider))),
2270 convert (ssizetype, BINFO_OFFSET (binfo)));
2272 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2275 BV_VCALL_INDEX (*virtuals)
2276 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2278 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2281 /* Called from modify_all_vtables via dfs_walk. */
2284 dfs_modify_vtables (tree binfo, void* data)
2286 tree t = (tree) data;
2291 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2292 /* A base without a vtable needs no modification, and its bases
2293 are uninteresting. */
2294 return dfs_skip_bases;
2296 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2297 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2298 /* Don't do the primary vtable, if it's new. */
2301 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2302 /* There's no need to modify the vtable for a non-virtual primary
2303 base; we're not going to use that vtable anyhow. We do still
2304 need to do this for virtual primary bases, as they could become
2305 non-primary in a construction vtable. */
2308 make_new_vtable (t, binfo);
2310 /* Now, go through each of the virtual functions in the virtual
2311 function table for BINFO. Find the final overrider, and update
2312 the BINFO_VIRTUALS list appropriately. */
2313 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2314 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2316 ix++, virtuals = TREE_CHAIN (virtuals),
2317 old_virtuals = TREE_CHAIN (old_virtuals))
2318 update_vtable_entry_for_fn (t,
2320 BV_FN (old_virtuals),
2326 /* Update all of the primary and secondary vtables for T. Create new
2327 vtables as required, and initialize their RTTI information. Each
2328 of the functions in VIRTUALS is declared in T and may override a
2329 virtual function from a base class; find and modify the appropriate
2330 entries to point to the overriding functions. Returns a list, in
2331 declaration order, of the virtual functions that are declared in T,
2332 but do not appear in the primary base class vtable, and which
2333 should therefore be appended to the end of the vtable for T. */
2336 modify_all_vtables (tree t, tree virtuals)
2338 tree binfo = TYPE_BINFO (t);
2341 /* Update all of the vtables. */
2342 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2344 /* Add virtual functions not already in our primary vtable. These
2345 will be both those introduced by this class, and those overridden
2346 from secondary bases. It does not include virtuals merely
2347 inherited from secondary bases. */
2348 for (fnsp = &virtuals; *fnsp; )
2350 tree fn = TREE_VALUE (*fnsp);
2352 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2353 || DECL_VINDEX (fn) == error_mark_node)
2355 /* We don't need to adjust the `this' pointer when
2356 calling this function. */
2357 BV_DELTA (*fnsp) = integer_zero_node;
2358 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2360 /* This is a function not already in our vtable. Keep it. */
2361 fnsp = &TREE_CHAIN (*fnsp);
2364 /* We've already got an entry for this function. Skip it. */
2365 *fnsp = TREE_CHAIN (*fnsp);
2371 /* Get the base virtual function declarations in T that have the
2375 get_basefndecls (tree name, tree t)
2378 tree base_fndecls = NULL_TREE;
2379 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2382 /* Find virtual functions in T with the indicated NAME. */
2383 i = lookup_fnfields_1 (t, name);
2385 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2387 methods = OVL_NEXT (methods))
2389 tree method = OVL_CURRENT (methods);
2391 if (TREE_CODE (method) == FUNCTION_DECL
2392 && DECL_VINDEX (method))
2393 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2397 return base_fndecls;
2399 for (i = 0; i < n_baseclasses; i++)
2401 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2402 base_fndecls = chainon (get_basefndecls (name, basetype),
2406 return base_fndecls;
2409 /* If this declaration supersedes the declaration of
2410 a method declared virtual in the base class, then
2411 mark this field as being virtual as well. */
2414 check_for_override (tree decl, tree ctype)
2416 if (TREE_CODE (decl) == TEMPLATE_DECL)
2417 /* In [temp.mem] we have:
2419 A specialization of a member function template does not
2420 override a virtual function from a base class. */
2422 if ((DECL_DESTRUCTOR_P (decl)
2423 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2424 || DECL_CONV_FN_P (decl))
2425 && look_for_overrides (ctype, decl)
2426 && !DECL_STATIC_FUNCTION_P (decl))
2427 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2428 the error_mark_node so that we know it is an overriding
2430 DECL_VINDEX (decl) = decl;
2432 if (DECL_VIRTUAL_P (decl))
2434 if (!DECL_VINDEX (decl))
2435 DECL_VINDEX (decl) = error_mark_node;
2436 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2440 /* Warn about hidden virtual functions that are not overridden in t.
2441 We know that constructors and destructors don't apply. */
2444 warn_hidden (tree t)
2446 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2450 /* We go through each separately named virtual function. */
2451 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2452 VEC_iterate (tree, method_vec, i, fns);
2463 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2464 have the same name. Figure out what name that is. */
2465 name = DECL_NAME (OVL_CURRENT (fns));
2466 /* There are no possibly hidden functions yet. */
2467 base_fndecls = NULL_TREE;
2468 /* Iterate through all of the base classes looking for possibly
2469 hidden functions. */
2470 for (binfo = TYPE_BINFO (t), j = 0;
2471 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2473 tree basetype = BINFO_TYPE (base_binfo);
2474 base_fndecls = chainon (get_basefndecls (name, basetype),
2478 /* If there are no functions to hide, continue. */
2482 /* Remove any overridden functions. */
2483 for (fn = fns; fn; fn = OVL_NEXT (fn))
2485 fndecl = OVL_CURRENT (fn);
2486 if (DECL_VINDEX (fndecl))
2488 tree *prev = &base_fndecls;
2491 /* If the method from the base class has the same
2492 signature as the method from the derived class, it
2493 has been overridden. */
2494 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2495 *prev = TREE_CHAIN (*prev);
2497 prev = &TREE_CHAIN (*prev);
2501 /* Now give a warning for all base functions without overriders,
2502 as they are hidden. */
2503 while (base_fndecls)
2505 /* Here we know it is a hider, and no overrider exists. */
2506 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2507 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2508 base_fndecls = TREE_CHAIN (base_fndecls);
2513 /* Check for things that are invalid. There are probably plenty of other
2514 things we should check for also. */
2517 finish_struct_anon (tree t)
2521 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2523 if (TREE_STATIC (field))
2525 if (TREE_CODE (field) != FIELD_DECL)
2528 if (DECL_NAME (field) == NULL_TREE
2529 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2531 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2532 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2533 for (; elt; elt = TREE_CHAIN (elt))
2535 /* We're generally only interested in entities the user
2536 declared, but we also find nested classes by noticing
2537 the TYPE_DECL that we create implicitly. You're
2538 allowed to put one anonymous union inside another,
2539 though, so we explicitly tolerate that. We use
2540 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2541 we also allow unnamed types used for defining fields. */
2542 if (DECL_ARTIFICIAL (elt)
2543 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2544 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2547 if (TREE_CODE (elt) != FIELD_DECL)
2550 permerror (input_location, "%q+#D invalid; an anonymous union can "
2551 "only have non-static data members", elt);
2553 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2554 "only have non-static data members", elt);
2558 if (TREE_PRIVATE (elt))
2561 permerror (input_location, "private member %q+#D in anonymous union", elt);
2563 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2565 else if (TREE_PROTECTED (elt))
2568 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2570 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2573 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2574 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2580 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2581 will be used later during class template instantiation.
2582 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2583 a non-static member data (FIELD_DECL), a member function
2584 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2585 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2586 When FRIEND_P is nonzero, T is either a friend class
2587 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2588 (FUNCTION_DECL, TEMPLATE_DECL). */
2591 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2593 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2594 if (CLASSTYPE_TEMPLATE_INFO (type))
2595 CLASSTYPE_DECL_LIST (type)
2596 = tree_cons (friend_p ? NULL_TREE : type,
2597 t, CLASSTYPE_DECL_LIST (type));
2600 /* Create default constructors, assignment operators, and so forth for
2601 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2602 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2603 the class cannot have a default constructor, copy constructor
2604 taking a const reference argument, or an assignment operator taking
2605 a const reference, respectively. */
2608 add_implicitly_declared_members (tree t,
2609 int cant_have_const_cctor,
2610 int cant_have_const_assignment)
2613 if (!CLASSTYPE_DESTRUCTORS (t))
2615 /* In general, we create destructors lazily. */
2616 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2617 /* However, if the implicit destructor is non-trivial
2618 destructor, we sometimes have to create it at this point. */
2619 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2623 if (TYPE_FOR_JAVA (t))
2624 /* If this a Java class, any non-trivial destructor is
2625 invalid, even if compiler-generated. Therefore, if the
2626 destructor is non-trivial we create it now. */
2634 /* If the implicit destructor will be virtual, then we must
2635 generate it now because (unfortunately) we do not
2636 generate virtual tables lazily. */
2637 binfo = TYPE_BINFO (t);
2638 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2643 base_type = BINFO_TYPE (base_binfo);
2644 dtor = CLASSTYPE_DESTRUCTORS (base_type);
2645 if (dtor && DECL_VIRTUAL_P (dtor))
2653 /* If we can't get away with being lazy, generate the destructor
2656 lazily_declare_fn (sfk_destructor, t);
2662 If there is no user-declared constructor for a class, a default
2663 constructor is implicitly declared. */
2664 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2666 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2667 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2672 If a class definition does not explicitly declare a copy
2673 constructor, one is declared implicitly. */
2674 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2676 TYPE_HAS_INIT_REF (t) = 1;
2677 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2678 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2681 /* If there is no assignment operator, one will be created if and
2682 when it is needed. For now, just record whether or not the type
2683 of the parameter to the assignment operator will be a const or
2684 non-const reference. */
2685 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2687 TYPE_HAS_ASSIGN_REF (t) = 1;
2688 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2689 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2693 /* Subroutine of finish_struct_1. Recursively count the number of fields
2694 in TYPE, including anonymous union members. */
2697 count_fields (tree fields)
2701 for (x = fields; x; x = TREE_CHAIN (x))
2703 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2704 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2711 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2712 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2715 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2718 for (x = fields; x; x = TREE_CHAIN (x))
2720 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2721 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2723 field_vec->elts[idx++] = x;
2728 /* FIELD is a bit-field. We are finishing the processing for its
2729 enclosing type. Issue any appropriate messages and set appropriate
2730 flags. Returns false if an error has been diagnosed. */
2733 check_bitfield_decl (tree field)
2735 tree type = TREE_TYPE (field);
2738 /* Extract the declared width of the bitfield, which has been
2739 temporarily stashed in DECL_INITIAL. */
2740 w = DECL_INITIAL (field);
2741 gcc_assert (w != NULL_TREE);
2742 /* Remove the bit-field width indicator so that the rest of the
2743 compiler does not treat that value as an initializer. */
2744 DECL_INITIAL (field) = NULL_TREE;
2746 /* Detect invalid bit-field type. */
2747 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2749 error ("bit-field %q+#D with non-integral type", field);
2750 w = error_mark_node;
2754 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2757 /* detect invalid field size. */
2758 w = integral_constant_value (w);
2760 if (TREE_CODE (w) != INTEGER_CST)
2762 error ("bit-field %q+D width not an integer constant", field);
2763 w = error_mark_node;
2765 else if (tree_int_cst_sgn (w) < 0)
2767 error ("negative width in bit-field %q+D", field);
2768 w = error_mark_node;
2770 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2772 error ("zero width for bit-field %q+D", field);
2773 w = error_mark_node;
2775 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2776 && TREE_CODE (type) != ENUMERAL_TYPE
2777 && TREE_CODE (type) != BOOLEAN_TYPE)
2778 warning (0, "width of %q+D exceeds its type", field);
2779 else if (TREE_CODE (type) == ENUMERAL_TYPE
2780 && (0 > compare_tree_int (w,
2781 tree_int_cst_min_precision
2782 (TYPE_MIN_VALUE (type),
2783 TYPE_UNSIGNED (type)))
2784 || 0 > compare_tree_int (w,
2785 tree_int_cst_min_precision
2786 (TYPE_MAX_VALUE (type),
2787 TYPE_UNSIGNED (type)))))
2788 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2791 if (w != error_mark_node)
2793 DECL_SIZE (field) = convert (bitsizetype, w);
2794 DECL_BIT_FIELD (field) = 1;
2799 /* Non-bit-fields are aligned for their type. */
2800 DECL_BIT_FIELD (field) = 0;
2801 CLEAR_DECL_C_BIT_FIELD (field);
2806 /* FIELD is a non bit-field. We are finishing the processing for its
2807 enclosing type T. Issue any appropriate messages and set appropriate
2811 check_field_decl (tree field,
2813 int* cant_have_const_ctor,
2814 int* no_const_asn_ref,
2815 int* any_default_members)
2817 tree type = strip_array_types (TREE_TYPE (field));
2819 /* An anonymous union cannot contain any fields which would change
2820 the settings of CANT_HAVE_CONST_CTOR and friends. */
2821 if (ANON_UNION_TYPE_P (type))
2823 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2824 structs. So, we recurse through their fields here. */
2825 else if (ANON_AGGR_TYPE_P (type))
2829 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2830 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2831 check_field_decl (fields, t, cant_have_const_ctor,
2832 no_const_asn_ref, any_default_members);
2834 /* Check members with class type for constructors, destructors,
2836 else if (CLASS_TYPE_P (type))
2838 /* Never let anything with uninheritable virtuals
2839 make it through without complaint. */
2840 abstract_virtuals_error (field, type);
2842 if (TREE_CODE (t) == UNION_TYPE)
2844 if (TYPE_NEEDS_CONSTRUCTING (type))
2845 error ("member %q+#D with constructor not allowed in union",
2847 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2848 error ("member %q+#D with destructor not allowed in union", field);
2849 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2850 error ("member %q+#D with copy assignment operator not allowed in union",
2855 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2856 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2857 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2858 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2859 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2860 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (type);
2863 if (!TYPE_HAS_CONST_INIT_REF (type))
2864 *cant_have_const_ctor = 1;
2866 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2867 *no_const_asn_ref = 1;
2869 if (DECL_INITIAL (field) != NULL_TREE)
2871 /* `build_class_init_list' does not recognize
2873 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2874 error ("multiple fields in union %qT initialized", t);
2875 *any_default_members = 1;
2879 /* Check the data members (both static and non-static), class-scoped
2880 typedefs, etc., appearing in the declaration of T. Issue
2881 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2882 declaration order) of access declarations; each TREE_VALUE in this
2883 list is a USING_DECL.
2885 In addition, set the following flags:
2888 The class is empty, i.e., contains no non-static data members.
2890 CANT_HAVE_CONST_CTOR_P
2891 This class cannot have an implicitly generated copy constructor
2892 taking a const reference.
2894 CANT_HAVE_CONST_ASN_REF
2895 This class cannot have an implicitly generated assignment
2896 operator taking a const reference.
2898 All of these flags should be initialized before calling this
2901 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2902 fields can be added by adding to this chain. */
2905 check_field_decls (tree t, tree *access_decls,
2906 int *cant_have_const_ctor_p,
2907 int *no_const_asn_ref_p)
2912 int any_default_members;
2914 int field_access = -1;
2916 /* Assume there are no access declarations. */
2917 *access_decls = NULL_TREE;
2918 /* Assume this class has no pointer members. */
2919 has_pointers = false;
2920 /* Assume none of the members of this class have default
2922 any_default_members = 0;
2924 for (field = &TYPE_FIELDS (t); *field; field = next)
2927 tree type = TREE_TYPE (x);
2928 int this_field_access;
2930 next = &TREE_CHAIN (x);
2932 if (TREE_CODE (x) == USING_DECL)
2934 /* Prune the access declaration from the list of fields. */
2935 *field = TREE_CHAIN (x);
2937 /* Save the access declarations for our caller. */
2938 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2940 /* Since we've reset *FIELD there's no reason to skip to the
2946 if (TREE_CODE (x) == TYPE_DECL
2947 || TREE_CODE (x) == TEMPLATE_DECL)
2950 /* If we've gotten this far, it's a data member, possibly static,
2951 or an enumerator. */
2952 DECL_CONTEXT (x) = t;
2954 /* When this goes into scope, it will be a non-local reference. */
2955 DECL_NONLOCAL (x) = 1;
2957 if (TREE_CODE (t) == UNION_TYPE)
2961 If a union contains a static data member, or a member of
2962 reference type, the program is ill-formed. */
2963 if (TREE_CODE (x) == VAR_DECL)
2965 error ("%q+D may not be static because it is a member of a union", x);
2968 if (TREE_CODE (type) == REFERENCE_TYPE)
2970 error ("%q+D may not have reference type %qT because"
2971 " it is a member of a union",
2977 /* Perform error checking that did not get done in
2979 if (TREE_CODE (type) == FUNCTION_TYPE)
2981 error ("field %q+D invalidly declared function type", x);
2982 type = build_pointer_type (type);
2983 TREE_TYPE (x) = type;
2985 else if (TREE_CODE (type) == METHOD_TYPE)
2987 error ("field %q+D invalidly declared method type", x);
2988 type = build_pointer_type (type);
2989 TREE_TYPE (x) = type;
2992 if (type == error_mark_node)
2995 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
2998 /* Now it can only be a FIELD_DECL. */
3000 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3001 CLASSTYPE_NON_AGGREGATE (t) = 1;
3003 /* A standard-layout class is a class that:
3005 has the same access control (Clause 11) for all non-static data members,
3007 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3008 if (field_access == -1)
3009 field_access = this_field_access;
3010 else if (this_field_access != field_access)
3011 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3013 /* If this is of reference type, check if it needs an init. */
3014 if (TREE_CODE (type) == REFERENCE_TYPE)
3016 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3017 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3018 if (DECL_INITIAL (x) == NULL_TREE)
3019 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3021 /* ARM $12.6.2: [A member initializer list] (or, for an
3022 aggregate, initialization by a brace-enclosed list) is the
3023 only way to initialize nonstatic const and reference
3025 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3028 type = strip_array_types (type);
3030 if (TYPE_PACKED (t))
3032 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3036 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3040 else if (DECL_C_BIT_FIELD (x)
3041 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3042 DECL_PACKED (x) = 1;
3045 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3046 /* We don't treat zero-width bitfields as making a class
3051 /* The class is non-empty. */
3052 CLASSTYPE_EMPTY_P (t) = 0;
3053 /* The class is not even nearly empty. */
3054 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3055 /* If one of the data members contains an empty class,
3057 if (CLASS_TYPE_P (type)
3058 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3059 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3062 /* This is used by -Weffc++ (see below). Warn only for pointers
3063 to members which might hold dynamic memory. So do not warn
3064 for pointers to functions or pointers to members. */
3065 if (TYPE_PTR_P (type)
3066 && !TYPE_PTRFN_P (type)
3067 && !TYPE_PTR_TO_MEMBER_P (type))
3068 has_pointers = true;
3070 if (CLASS_TYPE_P (type))
3072 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3073 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3074 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3075 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3078 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3079 CLASSTYPE_HAS_MUTABLE (t) = 1;
3081 if (! layout_pod_type_p (type))
3082 /* DR 148 now allows pointers to members (which are POD themselves),
3083 to be allowed in POD structs. */
3084 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3086 if (!std_layout_type_p (type))
3087 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3089 if (! zero_init_p (type))
3090 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3092 /* If any field is const, the structure type is pseudo-const. */
3093 if (CP_TYPE_CONST_P (type))
3095 C_TYPE_FIELDS_READONLY (t) = 1;
3096 if (DECL_INITIAL (x) == NULL_TREE)
3097 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3099 /* ARM $12.6.2: [A member initializer list] (or, for an
3100 aggregate, initialization by a brace-enclosed list) is the
3101 only way to initialize nonstatic const and reference
3103 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3105 /* A field that is pseudo-const makes the structure likewise. */
3106 else if (CLASS_TYPE_P (type))
3108 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3109 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3110 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3111 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3114 /* Core issue 80: A nonstatic data member is required to have a
3115 different name from the class iff the class has a
3116 user-declared constructor. */
3117 if (constructor_name_p (DECL_NAME (x), t)
3118 && TYPE_HAS_USER_CONSTRUCTOR (t))
3119 permerror (input_location, "field %q+#D with same name as class", x);
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);
3130 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3131 it should also define a copy constructor and an assignment operator to
3132 implement the correct copy semantic (deep vs shallow, etc.). As it is
3133 not feasible to check whether the constructors do allocate dynamic memory
3134 and store it within members, we approximate the warning like this:
3136 -- Warn only if there are members which are pointers
3137 -- Warn only if there is a non-trivial constructor (otherwise,
3138 there cannot be memory allocated).
3139 -- Warn only if there is a non-trivial destructor. We assume that the
3140 user at least implemented the cleanup correctly, and a destructor
3141 is needed to free dynamic memory.
3143 This seems enough for practical purposes. */
3146 && TYPE_HAS_USER_CONSTRUCTOR (t)
3147 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3148 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3150 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3152 if (! TYPE_HAS_INIT_REF (t))
3154 warning (OPT_Weffc__,
3155 " but does not override %<%T(const %T&)%>", t, t);
3156 if (!TYPE_HAS_ASSIGN_REF (t))
3157 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3159 else if (! TYPE_HAS_ASSIGN_REF (t))
3160 warning (OPT_Weffc__,
3161 " but does not override %<operator=(const %T&)%>", t);
3164 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3166 TYPE_PACKED (t) = 0;
3168 /* Check anonymous struct/anonymous union fields. */
3169 finish_struct_anon (t);
3171 /* We've built up the list of access declarations in reverse order.
3173 *access_decls = nreverse (*access_decls);
3176 /* If TYPE is an empty class type, records its OFFSET in the table of
3180 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3184 if (!is_empty_class (type))
3187 /* Record the location of this empty object in OFFSETS. */
3188 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3190 n = splay_tree_insert (offsets,
3191 (splay_tree_key) offset,
3192 (splay_tree_value) NULL_TREE);
3193 n->value = ((splay_tree_value)
3194 tree_cons (NULL_TREE,
3201 /* Returns nonzero if TYPE is an empty class type and there is
3202 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3205 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3210 if (!is_empty_class (type))
3213 /* Record the location of this empty object in OFFSETS. */
3214 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3218 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3219 if (same_type_p (TREE_VALUE (t), type))
3225 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3226 F for every subobject, passing it the type, offset, and table of
3227 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3230 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3231 than MAX_OFFSET will not be walked.
3233 If F returns a nonzero value, the traversal ceases, and that value
3234 is returned. Otherwise, returns zero. */
3237 walk_subobject_offsets (tree type,
3238 subobject_offset_fn f,
3245 tree type_binfo = NULL_TREE;
3247 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3249 if (max_offset && INT_CST_LT (max_offset, offset))
3252 if (type == error_mark_node)
3257 if (abi_version_at_least (2))
3259 type = BINFO_TYPE (type);
3262 if (CLASS_TYPE_P (type))
3268 /* Avoid recursing into objects that are not interesting. */
3269 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3272 /* Record the location of TYPE. */
3273 r = (*f) (type, offset, offsets);
3277 /* Iterate through the direct base classes of TYPE. */
3279 type_binfo = TYPE_BINFO (type);
3280 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3284 if (abi_version_at_least (2)
3285 && BINFO_VIRTUAL_P (binfo))
3289 && BINFO_VIRTUAL_P (binfo)
3290 && !BINFO_PRIMARY_P (binfo))
3293 if (!abi_version_at_least (2))
3294 binfo_offset = size_binop (PLUS_EXPR,
3296 BINFO_OFFSET (binfo));
3300 /* We cannot rely on BINFO_OFFSET being set for the base
3301 class yet, but the offsets for direct non-virtual
3302 bases can be calculated by going back to the TYPE. */
3303 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3304 binfo_offset = size_binop (PLUS_EXPR,
3306 BINFO_OFFSET (orig_binfo));
3309 r = walk_subobject_offsets (binfo,
3314 (abi_version_at_least (2)
3315 ? /*vbases_p=*/0 : vbases_p));
3320 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3323 VEC(tree,gc) *vbases;
3325 /* Iterate through the virtual base classes of TYPE. In G++
3326 3.2, we included virtual bases in the direct base class
3327 loop above, which results in incorrect results; the
3328 correct offsets for virtual bases are only known when
3329 working with the most derived type. */
3331 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3332 VEC_iterate (tree, vbases, ix, binfo); ix++)
3334 r = walk_subobject_offsets (binfo,
3336 size_binop (PLUS_EXPR,
3338 BINFO_OFFSET (binfo)),
3347 /* We still have to walk the primary base, if it is
3348 virtual. (If it is non-virtual, then it was walked
3350 tree vbase = get_primary_binfo (type_binfo);
3352 if (vbase && BINFO_VIRTUAL_P (vbase)
3353 && BINFO_PRIMARY_P (vbase)
3354 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3356 r = (walk_subobject_offsets
3358 offsets, max_offset, /*vbases_p=*/0));
3365 /* Iterate through the fields of TYPE. */
3366 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3367 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3371 if (abi_version_at_least (2))
3372 field_offset = byte_position (field);
3374 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3375 field_offset = DECL_FIELD_OFFSET (field);
3377 r = walk_subobject_offsets (TREE_TYPE (field),
3379 size_binop (PLUS_EXPR,
3389 else if (TREE_CODE (type) == ARRAY_TYPE)
3391 tree element_type = strip_array_types (type);
3392 tree domain = TYPE_DOMAIN (type);
3395 /* Avoid recursing into objects that are not interesting. */
3396 if (!CLASS_TYPE_P (element_type)
3397 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3400 /* Step through each of the elements in the array. */
3401 for (index = size_zero_node;
3402 /* G++ 3.2 had an off-by-one error here. */
3403 (abi_version_at_least (2)
3404 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3405 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3406 index = size_binop (PLUS_EXPR, index, size_one_node))
3408 r = walk_subobject_offsets (TREE_TYPE (type),
3416 offset = size_binop (PLUS_EXPR, offset,
3417 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3418 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3419 there's no point in iterating through the remaining
3420 elements of the array. */
3421 if (max_offset && INT_CST_LT (max_offset, offset))
3429 /* Record all of the empty subobjects of TYPE (either a type or a
3430 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3431 is being placed at OFFSET; otherwise, it is a base class that is
3432 being placed at OFFSET. */
3435 record_subobject_offsets (tree type,
3438 bool is_data_member)
3441 /* If recording subobjects for a non-static data member or a
3442 non-empty base class , we do not need to record offsets beyond
3443 the size of the biggest empty class. Additional data members
3444 will go at the end of the class. Additional base classes will go
3445 either at offset zero (if empty, in which case they cannot
3446 overlap with offsets past the size of the biggest empty class) or
3447 at the end of the class.
3449 However, if we are placing an empty base class, then we must record
3450 all offsets, as either the empty class is at offset zero (where
3451 other empty classes might later be placed) or at the end of the
3452 class (where other objects might then be placed, so other empty
3453 subobjects might later overlap). */
3455 || !is_empty_class (BINFO_TYPE (type)))
3456 max_offset = sizeof_biggest_empty_class;
3458 max_offset = NULL_TREE;
3459 walk_subobject_offsets (type, record_subobject_offset, offset,
3460 offsets, max_offset, is_data_member);
3463 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3464 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3465 virtual bases of TYPE are examined. */
3468 layout_conflict_p (tree type,
3473 splay_tree_node max_node;
3475 /* Get the node in OFFSETS that indicates the maximum offset where
3476 an empty subobject is located. */
3477 max_node = splay_tree_max (offsets);
3478 /* If there aren't any empty subobjects, then there's no point in
3479 performing this check. */
3483 return walk_subobject_offsets (type, check_subobject_offset, offset,
3484 offsets, (tree) (max_node->key),
3488 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3489 non-static data member of the type indicated by RLI. BINFO is the
3490 binfo corresponding to the base subobject, OFFSETS maps offsets to
3491 types already located at those offsets. This function determines
3492 the position of the DECL. */
3495 layout_nonempty_base_or_field (record_layout_info rli,
3500 tree offset = NULL_TREE;
3506 /* For the purposes of determining layout conflicts, we want to
3507 use the class type of BINFO; TREE_TYPE (DECL) will be the
3508 CLASSTYPE_AS_BASE version, which does not contain entries for
3509 zero-sized bases. */
3510 type = TREE_TYPE (binfo);
3515 type = TREE_TYPE (decl);
3519 /* Try to place the field. It may take more than one try if we have
3520 a hard time placing the field without putting two objects of the
3521 same type at the same address. */
3524 struct record_layout_info_s old_rli = *rli;
3526 /* Place this field. */
3527 place_field (rli, decl);
3528 offset = byte_position (decl);
3530 /* We have to check to see whether or not there is already
3531 something of the same type at the offset we're about to use.
3532 For example, consider:
3535 struct T : public S { int i; };
3536 struct U : public S, public T {};
3538 Here, we put S at offset zero in U. Then, we can't put T at
3539 offset zero -- its S component would be at the same address
3540 as the S we already allocated. So, we have to skip ahead.
3541 Since all data members, including those whose type is an
3542 empty class, have nonzero size, any overlap can happen only
3543 with a direct or indirect base-class -- it can't happen with
3545 /* In a union, overlap is permitted; all members are placed at
3547 if (TREE_CODE (rli->t) == UNION_TYPE)
3549 /* G++ 3.2 did not check for overlaps when placing a non-empty
3551 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3553 if (layout_conflict_p (field_p ? type : binfo, offset,
3556 /* Strip off the size allocated to this field. That puts us
3557 at the first place we could have put the field with
3558 proper alignment. */
3561 /* Bump up by the alignment required for the type. */
3563 = size_binop (PLUS_EXPR, rli->bitpos,
3565 ? CLASSTYPE_ALIGN (type)
3566 : TYPE_ALIGN (type)));
3567 normalize_rli (rli);
3570 /* There was no conflict. We're done laying out this field. */
3574 /* Now that we know where it will be placed, update its
3576 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3577 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3578 this point because their BINFO_OFFSET is copied from another
3579 hierarchy. Therefore, we may not need to add the entire
3581 propagate_binfo_offsets (binfo,
3582 size_diffop_loc (input_location,
3583 convert (ssizetype, offset),
3585 BINFO_OFFSET (binfo))));
3588 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3591 empty_base_at_nonzero_offset_p (tree type,
3593 splay_tree offsets ATTRIBUTE_UNUSED)
3595 return is_empty_class (type) && !integer_zerop (offset);
3598 /* Layout the empty base BINFO. EOC indicates the byte currently just
3599 past the end of the class, and should be correctly aligned for a
3600 class of the type indicated by BINFO; OFFSETS gives the offsets of
3601 the empty bases allocated so far. T is the most derived
3602 type. Return nonzero iff we added it at the end. */
3605 layout_empty_base (record_layout_info rli, tree binfo,
3606 tree eoc, splay_tree offsets)
3609 tree basetype = BINFO_TYPE (binfo);
3612 /* This routine should only be used for empty classes. */
3613 gcc_assert (is_empty_class (basetype));
3614 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3616 if (!integer_zerop (BINFO_OFFSET (binfo)))
3618 if (abi_version_at_least (2))
3619 propagate_binfo_offsets
3620 (binfo, size_diffop_loc (input_location,
3621 size_zero_node, BINFO_OFFSET (binfo)));
3624 "offset of empty base %qT may not be ABI-compliant and may"
3625 "change in a future version of GCC",
3626 BINFO_TYPE (binfo));
3629 /* This is an empty base class. We first try to put it at offset
3631 if (layout_conflict_p (binfo,
3632 BINFO_OFFSET (binfo),
3636 /* That didn't work. Now, we move forward from the next
3637 available spot in the class. */
3639 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3642 if (!layout_conflict_p (binfo,
3643 BINFO_OFFSET (binfo),
3646 /* We finally found a spot where there's no overlap. */
3649 /* There's overlap here, too. Bump along to the next spot. */
3650 propagate_binfo_offsets (binfo, alignment);
3654 if (CLASSTYPE_USER_ALIGN (basetype))
3656 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3658 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3659 TYPE_USER_ALIGN (rli->t) = 1;
3665 /* Layout the base given by BINFO in the class indicated by RLI.
3666 *BASE_ALIGN is a running maximum of the alignments of
3667 any base class. OFFSETS gives the location of empty base
3668 subobjects. T is the most derived type. Return nonzero if the new
3669 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3670 *NEXT_FIELD, unless BINFO is for an empty base class.
3672 Returns the location at which the next field should be inserted. */
3675 build_base_field (record_layout_info rli, tree binfo,
3676 splay_tree offsets, tree *next_field)
3679 tree basetype = BINFO_TYPE (binfo);
3681 if (!COMPLETE_TYPE_P (basetype))
3682 /* This error is now reported in xref_tag, thus giving better
3683 location information. */
3686 /* Place the base class. */
3687 if (!is_empty_class (basetype))
3691 /* The containing class is non-empty because it has a non-empty
3693 CLASSTYPE_EMPTY_P (t) = 0;
3695 /* Create the FIELD_DECL. */
3696 decl = build_decl (input_location,
3697 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3698 DECL_ARTIFICIAL (decl) = 1;
3699 DECL_IGNORED_P (decl) = 1;
3700 DECL_FIELD_CONTEXT (decl) = t;
3701 if (CLASSTYPE_AS_BASE (basetype))
3703 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3704 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3705 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3706 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3707 DECL_MODE (decl) = TYPE_MODE (basetype);
3708 DECL_FIELD_IS_BASE (decl) = 1;
3710 /* Try to place the field. It may take more than one try if we
3711 have a hard time placing the field without putting two
3712 objects of the same type at the same address. */
3713 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3714 /* Add the new FIELD_DECL to the list of fields for T. */
3715 TREE_CHAIN (decl) = *next_field;
3717 next_field = &TREE_CHAIN (decl);
3725 /* On some platforms (ARM), even empty classes will not be
3727 eoc = round_up_loc (input_location,
3728 rli_size_unit_so_far (rli),
3729 CLASSTYPE_ALIGN_UNIT (basetype));
3730 atend = layout_empty_base (rli, binfo, eoc, offsets);
3731 /* A nearly-empty class "has no proper base class that is empty,
3732 not morally virtual, and at an offset other than zero." */
3733 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3736 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3737 /* The check above (used in G++ 3.2) is insufficient because
3738 an empty class placed at offset zero might itself have an
3739 empty base at a nonzero offset. */
3740 else if (walk_subobject_offsets (basetype,
3741 empty_base_at_nonzero_offset_p,
3744 /*max_offset=*/NULL_TREE,
3747 if (abi_version_at_least (2))
3748 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3751 "class %qT will be considered nearly empty in a "
3752 "future version of GCC", t);
3756 /* We do not create a FIELD_DECL for empty base classes because
3757 it might overlap some other field. We want to be able to
3758 create CONSTRUCTORs for the class by iterating over the
3759 FIELD_DECLs, and the back end does not handle overlapping
3762 /* An empty virtual base causes a class to be non-empty
3763 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3764 here because that was already done when the virtual table
3765 pointer was created. */
3768 /* Record the offsets of BINFO and its base subobjects. */
3769 record_subobject_offsets (binfo,
3770 BINFO_OFFSET (binfo),
3772 /*is_data_member=*/false);
3777 /* Layout all of the non-virtual base classes. Record empty
3778 subobjects in OFFSETS. T is the most derived type. Return nonzero
3779 if the type cannot be nearly empty. The fields created
3780 corresponding to the base classes will be inserted at
3784 build_base_fields (record_layout_info rli,
3785 splay_tree offsets, tree *next_field)
3787 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3790 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3793 /* The primary base class is always allocated first. */
3794 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3795 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3796 offsets, next_field);
3798 /* Now allocate the rest of the bases. */
3799 for (i = 0; i < n_baseclasses; ++i)
3803 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3805 /* The primary base was already allocated above, so we don't
3806 need to allocate it again here. */
3807 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3810 /* Virtual bases are added at the end (a primary virtual base
3811 will have already been added). */
3812 if (BINFO_VIRTUAL_P (base_binfo))
3815 next_field = build_base_field (rli, base_binfo,
3816 offsets, next_field);
3820 /* Go through the TYPE_METHODS of T issuing any appropriate
3821 diagnostics, figuring out which methods override which other
3822 methods, and so forth. */
3825 check_methods (tree t)
3829 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3831 check_for_override (x, t);
3832 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3833 error ("initializer specified for non-virtual method %q+D", x);
3834 /* The name of the field is the original field name
3835 Save this in auxiliary field for later overloading. */
3836 if (DECL_VINDEX (x))
3838 TYPE_POLYMORPHIC_P (t) = 1;
3839 if (DECL_PURE_VIRTUAL_P (x))
3840 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3842 /* All user-provided destructors are non-trivial. */
3843 if (DECL_DESTRUCTOR_P (x) && !DECL_DEFAULTED_FN (x))
3844 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3848 /* FN is a constructor or destructor. Clone the declaration to create
3849 a specialized in-charge or not-in-charge version, as indicated by
3853 build_clone (tree fn, tree name)
3858 /* Copy the function. */
3859 clone = copy_decl (fn);
3860 /* Reset the function name. */
3861 DECL_NAME (clone) = name;
3862 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3863 /* Remember where this function came from. */
3864 DECL_ABSTRACT_ORIGIN (clone) = fn;
3865 /* Make it easy to find the CLONE given the FN. */
3866 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3867 TREE_CHAIN (fn) = clone;
3869 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3870 if (TREE_CODE (clone) == TEMPLATE_DECL)
3872 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3873 DECL_TEMPLATE_RESULT (clone) = result;
3874 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3875 DECL_TI_TEMPLATE (result) = clone;
3876 TREE_TYPE (clone) = TREE_TYPE (result);
3880 DECL_CLONED_FUNCTION (clone) = fn;
3881 /* There's no pending inline data for this function. */
3882 DECL_PENDING_INLINE_INFO (clone) = NULL;
3883 DECL_PENDING_INLINE_P (clone) = 0;
3884 /* And it hasn't yet been deferred. */
3885 DECL_DEFERRED_FN (clone) = 0;
3887 /* The base-class destructor is not virtual. */
3888 if (name == base_dtor_identifier)
3890 DECL_VIRTUAL_P (clone) = 0;
3891 if (TREE_CODE (clone) != TEMPLATE_DECL)
3892 DECL_VINDEX (clone) = NULL_TREE;
3895 /* If there was an in-charge parameter, drop it from the function
3897 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3903 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3904 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3905 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3906 /* Skip the `this' parameter. */
3907 parmtypes = TREE_CHAIN (parmtypes);
3908 /* Skip the in-charge parameter. */
3909 parmtypes = TREE_CHAIN (parmtypes);
3910 /* And the VTT parm, in a complete [cd]tor. */
3911 if (DECL_HAS_VTT_PARM_P (fn)
3912 && ! DECL_NEEDS_VTT_PARM_P (clone))
3913 parmtypes = TREE_CHAIN (parmtypes);
3914 /* If this is subobject constructor or destructor, add the vtt
3917 = build_method_type_directly (basetype,
3918 TREE_TYPE (TREE_TYPE (clone)),
3921 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3924 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3925 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3928 /* Copy the function parameters. */
3929 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3930 /* Remove the in-charge parameter. */
3931 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3933 TREE_CHAIN (DECL_ARGUMENTS (clone))
3934 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3935 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3937 /* And the VTT parm, in a complete [cd]tor. */
3938 if (DECL_HAS_VTT_PARM_P (fn))
3940 if (DECL_NEEDS_VTT_PARM_P (clone))
3941 DECL_HAS_VTT_PARM_P (clone) = 1;
3944 TREE_CHAIN (DECL_ARGUMENTS (clone))
3945 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3946 DECL_HAS_VTT_PARM_P (clone) = 0;
3950 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3952 DECL_CONTEXT (parms) = clone;
3953 cxx_dup_lang_specific_decl (parms);
3956 /* Create the RTL for this function. */
3957 SET_DECL_RTL (clone, NULL_RTX);
3958 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3961 note_decl_for_pch (clone);
3966 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
3967 not invoke this function directly.
3969 For a non-thunk function, returns the address of the slot for storing
3970 the function it is a clone of. Otherwise returns NULL_TREE.
3972 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
3973 cloned_function is unset. This is to support the separate
3974 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
3975 on a template makes sense, but not the former. */
3978 decl_cloned_function_p (const_tree decl, bool just_testing)
3982 decl = STRIP_TEMPLATE (decl);
3984 if (TREE_CODE (decl) != FUNCTION_DECL
3985 || !DECL_LANG_SPECIFIC (decl)
3986 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
3988 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
3990 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
3996 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
3997 if (just_testing && *ptr == NULL_TREE)
4003 /* Produce declarations for all appropriate clones of FN. If
4004 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4005 CLASTYPE_METHOD_VEC as well. */
4008 clone_function_decl (tree fn, int update_method_vec_p)
4012 /* Avoid inappropriate cloning. */
4014 && DECL_CLONED_FUNCTION_P (TREE_CHAIN (fn)))
4017 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4019 /* For each constructor, we need two variants: an in-charge version
4020 and a not-in-charge version. */
4021 clone = build_clone (fn, complete_ctor_identifier);
4022 if (update_method_vec_p)
4023 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4024 clone = build_clone (fn, base_ctor_identifier);
4025 if (update_method_vec_p)
4026 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4030 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4032 /* For each destructor, we need three variants: an in-charge
4033 version, a not-in-charge version, and an in-charge deleting
4034 version. We clone the deleting version first because that
4035 means it will go second on the TYPE_METHODS list -- and that
4036 corresponds to the correct layout order in the virtual
4039 For a non-virtual destructor, we do not build a deleting
4041 if (DECL_VIRTUAL_P (fn))
4043 clone = build_clone (fn, deleting_dtor_identifier);
4044 if (update_method_vec_p)
4045 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4047 clone = build_clone (fn, complete_dtor_identifier);
4048 if (update_method_vec_p)
4049 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4050 clone = build_clone (fn, base_dtor_identifier);
4051 if (update_method_vec_p)
4052 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4055 /* Note that this is an abstract function that is never emitted. */
4056 DECL_ABSTRACT (fn) = 1;
4059 /* DECL is an in charge constructor, which is being defined. This will
4060 have had an in class declaration, from whence clones were
4061 declared. An out-of-class definition can specify additional default
4062 arguments. As it is the clones that are involved in overload
4063 resolution, we must propagate the information from the DECL to its
4067 adjust_clone_args (tree decl)
4071 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4072 clone = TREE_CHAIN (clone))
4074 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4075 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4076 tree decl_parms, clone_parms;
4078 clone_parms = orig_clone_parms;
4080 /* Skip the 'this' parameter. */
4081 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4082 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4084 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4085 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4086 if (DECL_HAS_VTT_PARM_P (decl))
4087 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4089 clone_parms = orig_clone_parms;
4090 if (DECL_HAS_VTT_PARM_P (clone))
4091 clone_parms = TREE_CHAIN (clone_parms);
4093 for (decl_parms = orig_decl_parms; decl_parms;
4094 decl_parms = TREE_CHAIN (decl_parms),
4095 clone_parms = TREE_CHAIN (clone_parms))
4097 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4098 TREE_TYPE (clone_parms)));
4100 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4102 /* A default parameter has been added. Adjust the
4103 clone's parameters. */
4104 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4105 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4108 clone_parms = orig_decl_parms;
4110 if (DECL_HAS_VTT_PARM_P (clone))
4112 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4113 TREE_VALUE (orig_clone_parms),
4115 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4117 type = build_method_type_directly (basetype,
4118 TREE_TYPE (TREE_TYPE (clone)),
4121 type = build_exception_variant (type, exceptions);
4122 TREE_TYPE (clone) = type;
4124 clone_parms = NULL_TREE;
4128 gcc_assert (!clone_parms);
4132 /* For each of the constructors and destructors in T, create an
4133 in-charge and not-in-charge variant. */
4136 clone_constructors_and_destructors (tree t)
4140 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4142 if (!CLASSTYPE_METHOD_VEC (t))
4145 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4146 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4147 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4148 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4151 /* Returns true iff class T has a user-defined constructor other than
4152 the default constructor. */
4155 type_has_user_nondefault_constructor (tree t)
4159 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4162 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4164 tree fn = OVL_CURRENT (fns);
4165 if (!DECL_ARTIFICIAL (fn)
4166 && (TREE_CODE (fn) == TEMPLATE_DECL
4167 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4175 /* Returns true iff FN is a user-provided function, i.e. user-declared
4176 and not defaulted at its first declaration. */
4179 user_provided_p (tree fn)
4181 if (TREE_CODE (fn) == TEMPLATE_DECL)
4184 return (!DECL_ARTIFICIAL (fn)
4185 && !(DECL_DEFAULTED_FN (fn)
4186 && DECL_INITIALIZED_IN_CLASS_P (fn)));
4189 /* Returns true iff class T has a user-provided constructor. */
4192 type_has_user_provided_constructor (tree t)
4196 if (!CLASS_TYPE_P (t))
4199 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4202 /* This can happen in error cases; avoid crashing. */
4203 if (!CLASSTYPE_METHOD_VEC (t))
4206 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4207 if (user_provided_p (OVL_CURRENT (fns)))
4213 /* Returns true iff class T has a user-provided default constructor. */
4216 type_has_user_provided_default_constructor (tree t)
4220 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4223 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4225 tree fn = OVL_CURRENT (fns);
4226 if (TREE_CODE (fn) == FUNCTION_DECL
4227 && user_provided_p (fn))
4229 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4230 while (args && TREE_PURPOSE (args))
4231 args = TREE_CHAIN (args);
4232 if (!args || args == void_list_node)
4240 /* Returns true if FN can be explicitly defaulted. */
4243 defaultable_fn_p (tree fn)
4245 if (DECL_CONSTRUCTOR_P (fn))
4247 if (FUNCTION_FIRST_USER_PARMTYPE (fn) == void_list_node)
4249 else if (copy_fn_p (fn) > 0
4250 && (TREE_CHAIN (FUNCTION_FIRST_USER_PARMTYPE (fn))
4256 else if (DECL_DESTRUCTOR_P (fn))
4258 else if (DECL_ASSIGNMENT_OPERATOR_P (fn)
4259 && DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR)
4260 return copy_fn_p (fn);
4265 /* Remove all zero-width bit-fields from T. */
4268 remove_zero_width_bit_fields (tree t)
4272 fieldsp = &TYPE_FIELDS (t);
4275 if (TREE_CODE (*fieldsp) == FIELD_DECL
4276 && DECL_C_BIT_FIELD (*fieldsp)
4277 && DECL_INITIAL (*fieldsp))
4278 *fieldsp = TREE_CHAIN (*fieldsp);
4280 fieldsp = &TREE_CHAIN (*fieldsp);
4284 /* Returns TRUE iff we need a cookie when dynamically allocating an
4285 array whose elements have the indicated class TYPE. */
4288 type_requires_array_cookie (tree type)
4291 bool has_two_argument_delete_p = false;
4293 gcc_assert (CLASS_TYPE_P (type));
4295 /* If there's a non-trivial destructor, we need a cookie. In order
4296 to iterate through the array calling the destructor for each
4297 element, we'll have to know how many elements there are. */
4298 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4301 /* If the usual deallocation function is a two-argument whose second
4302 argument is of type `size_t', then we have to pass the size of
4303 the array to the deallocation function, so we will need to store
4305 fns = lookup_fnfields (TYPE_BINFO (type),
4306 ansi_opname (VEC_DELETE_EXPR),
4308 /* If there are no `operator []' members, or the lookup is
4309 ambiguous, then we don't need a cookie. */
4310 if (!fns || fns == error_mark_node)
4312 /* Loop through all of the functions. */
4313 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4318 /* Select the current function. */
4319 fn = OVL_CURRENT (fns);
4320 /* See if this function is a one-argument delete function. If
4321 it is, then it will be the usual deallocation function. */
4322 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4323 if (second_parm == void_list_node)
4325 /* Do not consider this function if its second argument is an
4329 /* Otherwise, if we have a two-argument function and the second
4330 argument is `size_t', it will be the usual deallocation
4331 function -- unless there is one-argument function, too. */
4332 if (TREE_CHAIN (second_parm) == void_list_node
4333 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4334 has_two_argument_delete_p = true;
4337 return has_two_argument_delete_p;
4340 /* Check the validity of the bases and members declared in T. Add any
4341 implicitly-generated functions (like copy-constructors and
4342 assignment operators). Compute various flag bits (like
4343 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4344 level: i.e., independently of the ABI in use. */
4347 check_bases_and_members (tree t)
4349 /* Nonzero if the implicitly generated copy constructor should take
4350 a non-const reference argument. */
4351 int cant_have_const_ctor;
4352 /* Nonzero if the implicitly generated assignment operator
4353 should take a non-const reference argument. */
4354 int no_const_asn_ref;
4356 bool saved_complex_asn_ref;
4357 bool saved_nontrivial_dtor;
4359 /* By default, we use const reference arguments and generate default
4361 cant_have_const_ctor = 0;
4362 no_const_asn_ref = 0;
4364 /* Check all the base-classes. */
4365 check_bases (t, &cant_have_const_ctor,
4368 /* Check all the method declarations. */
4371 /* Save the initial values of these flags which only indicate whether
4372 or not the class has user-provided functions. As we analyze the
4373 bases and members we can set these flags for other reasons. */
4374 saved_complex_asn_ref = TYPE_HAS_COMPLEX_ASSIGN_REF (t);
4375 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4377 /* Check all the data member declarations. We cannot call
4378 check_field_decls until we have called check_bases check_methods,
4379 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4380 being set appropriately. */
4381 check_field_decls (t, &access_decls,
4382 &cant_have_const_ctor,
4385 /* A nearly-empty class has to be vptr-containing; a nearly empty
4386 class contains just a vptr. */
4387 if (!TYPE_CONTAINS_VPTR_P (t))
4388 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4390 /* Do some bookkeeping that will guide the generation of implicitly
4391 declared member functions. */
4392 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4393 /* We need to call a constructor for this class if it has a
4394 user-provided constructor, or if the default constructor is going
4395 to initialize the vptr. (This is not an if-and-only-if;
4396 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4397 themselves need constructing.) */
4398 TYPE_NEEDS_CONSTRUCTING (t)
4399 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4402 An aggregate is an array or a class with no user-provided
4403 constructors ... and no virtual functions.
4405 Again, other conditions for being an aggregate are checked
4407 CLASSTYPE_NON_AGGREGATE (t)
4408 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4409 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4410 retain the old definition internally for ABI reasons. */
4411 CLASSTYPE_NON_LAYOUT_POD_P (t)
4412 |= (CLASSTYPE_NON_AGGREGATE (t)
4413 || saved_nontrivial_dtor || saved_complex_asn_ref);
4414 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
4415 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4416 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4418 /* If the class has no user-declared constructor, but does have
4419 non-static const or reference data members that can never be
4420 initialized, issue a warning. */
4421 if (warn_uninitialized
4422 /* Classes with user-declared constructors are presumed to
4423 initialize these members. */
4424 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4425 /* Aggregates can be initialized with brace-enclosed
4427 && CLASSTYPE_NON_AGGREGATE (t))
4431 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4435 if (TREE_CODE (field) != FIELD_DECL)
4438 type = TREE_TYPE (field);
4439 if (TREE_CODE (type) == REFERENCE_TYPE)
4440 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4441 "in class without a constructor", field);
4442 else if (CP_TYPE_CONST_P (type)
4443 && (!CLASS_TYPE_P (type)
4444 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4445 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4446 "in class without a constructor", field);
4450 /* Synthesize any needed methods. */
4451 add_implicitly_declared_members (t,
4452 cant_have_const_ctor,
4455 /* Create the in-charge and not-in-charge variants of constructors
4457 clone_constructors_and_destructors (t);
4459 /* Process the using-declarations. */
4460 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4461 handle_using_decl (TREE_VALUE (access_decls), t);
4463 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4464 finish_struct_methods (t);
4466 /* Figure out whether or not we will need a cookie when dynamically
4467 allocating an array of this type. */
4468 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4469 = type_requires_array_cookie (t);
4472 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4473 accordingly. If a new vfield was created (because T doesn't have a
4474 primary base class), then the newly created field is returned. It
4475 is not added to the TYPE_FIELDS list; it is the caller's
4476 responsibility to do that. Accumulate declared virtual functions
4480 create_vtable_ptr (tree t, tree* virtuals_p)
4484 /* Collect the virtual functions declared in T. */
4485 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4486 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4487 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4489 tree new_virtual = make_node (TREE_LIST);
4491 BV_FN (new_virtual) = fn;
4492 BV_DELTA (new_virtual) = integer_zero_node;
4493 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4495 TREE_CHAIN (new_virtual) = *virtuals_p;
4496 *virtuals_p = new_virtual;
4499 /* If we couldn't find an appropriate base class, create a new field
4500 here. Even if there weren't any new virtual functions, we might need a
4501 new virtual function table if we're supposed to include vptrs in
4502 all classes that need them. */
4503 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4505 /* We build this decl with vtbl_ptr_type_node, which is a
4506 `vtable_entry_type*'. It might seem more precise to use
4507 `vtable_entry_type (*)[N]' where N is the number of virtual
4508 functions. However, that would require the vtable pointer in
4509 base classes to have a different type than the vtable pointer
4510 in derived classes. We could make that happen, but that
4511 still wouldn't solve all the problems. In particular, the
4512 type-based alias analysis code would decide that assignments
4513 to the base class vtable pointer can't alias assignments to
4514 the derived class vtable pointer, since they have different
4515 types. Thus, in a derived class destructor, where the base
4516 class constructor was inlined, we could generate bad code for
4517 setting up the vtable pointer.
4519 Therefore, we use one type for all vtable pointers. We still
4520 use a type-correct type; it's just doesn't indicate the array
4521 bounds. That's better than using `void*' or some such; it's
4522 cleaner, and it let's the alias analysis code know that these
4523 stores cannot alias stores to void*! */
4526 field = build_decl (input_location,
4527 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4528 DECL_VIRTUAL_P (field) = 1;
4529 DECL_ARTIFICIAL (field) = 1;
4530 DECL_FIELD_CONTEXT (field) = t;
4531 DECL_FCONTEXT (field) = t;
4533 TYPE_VFIELD (t) = field;
4535 /* This class is non-empty. */
4536 CLASSTYPE_EMPTY_P (t) = 0;
4544 /* Add OFFSET to all base types of BINFO which is a base in the
4545 hierarchy dominated by T.
4547 OFFSET, which is a type offset, is number of bytes. */
4550 propagate_binfo_offsets (tree binfo, tree offset)
4556 /* Update BINFO's offset. */
4557 BINFO_OFFSET (binfo)
4558 = convert (sizetype,
4559 size_binop (PLUS_EXPR,
4560 convert (ssizetype, BINFO_OFFSET (binfo)),
4563 /* Find the primary base class. */
4564 primary_binfo = get_primary_binfo (binfo);
4566 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4567 propagate_binfo_offsets (primary_binfo, offset);
4569 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4571 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4573 /* Don't do the primary base twice. */
4574 if (base_binfo == primary_binfo)
4577 if (BINFO_VIRTUAL_P (base_binfo))
4580 propagate_binfo_offsets (base_binfo, offset);
4584 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4585 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4586 empty subobjects of T. */
4589 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4593 bool first_vbase = true;
4596 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4599 if (!abi_version_at_least(2))
4601 /* In G++ 3.2, we incorrectly rounded the size before laying out
4602 the virtual bases. */
4603 finish_record_layout (rli, /*free_p=*/false);
4604 #ifdef STRUCTURE_SIZE_BOUNDARY
4605 /* Packed structures don't need to have minimum size. */
4606 if (! TYPE_PACKED (t))
4607 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4609 rli->offset = TYPE_SIZE_UNIT (t);
4610 rli->bitpos = bitsize_zero_node;
4611 rli->record_align = TYPE_ALIGN (t);
4614 /* Find the last field. The artificial fields created for virtual
4615 bases will go after the last extant field to date. */
4616 next_field = &TYPE_FIELDS (t);
4618 next_field = &TREE_CHAIN (*next_field);
4620 /* Go through the virtual bases, allocating space for each virtual
4621 base that is not already a primary base class. These are
4622 allocated in inheritance graph order. */
4623 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4625 if (!BINFO_VIRTUAL_P (vbase))
4628 if (!BINFO_PRIMARY_P (vbase))
4630 tree basetype = TREE_TYPE (vbase);
4632 /* This virtual base is not a primary base of any class in the
4633 hierarchy, so we have to add space for it. */
4634 next_field = build_base_field (rli, vbase,
4635 offsets, next_field);
4637 /* If the first virtual base might have been placed at a
4638 lower address, had we started from CLASSTYPE_SIZE, rather
4639 than TYPE_SIZE, issue a warning. There can be both false
4640 positives and false negatives from this warning in rare
4641 cases; to deal with all the possibilities would probably
4642 require performing both layout algorithms and comparing
4643 the results which is not particularly tractable. */
4647 (size_binop (CEIL_DIV_EXPR,
4648 round_up_loc (input_location,
4650 CLASSTYPE_ALIGN (basetype)),
4652 BINFO_OFFSET (vbase))))
4654 "offset of virtual base %qT is not ABI-compliant and "
4655 "may change in a future version of GCC",
4658 first_vbase = false;
4663 /* Returns the offset of the byte just past the end of the base class
4667 end_of_base (tree binfo)
4671 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
4672 size = TYPE_SIZE_UNIT (char_type_node);
4673 else if (is_empty_class (BINFO_TYPE (binfo)))
4674 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4675 allocate some space for it. It cannot have virtual bases, so
4676 TYPE_SIZE_UNIT is fine. */
4677 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4679 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4681 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4684 /* Returns the offset of the byte just past the end of the base class
4685 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4686 only non-virtual bases are included. */
4689 end_of_class (tree t, int include_virtuals_p)
4691 tree result = size_zero_node;
4692 VEC(tree,gc) *vbases;
4698 for (binfo = TYPE_BINFO (t), i = 0;
4699 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4701 if (!include_virtuals_p
4702 && BINFO_VIRTUAL_P (base_binfo)
4703 && (!BINFO_PRIMARY_P (base_binfo)
4704 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4707 offset = end_of_base (base_binfo);
4708 if (INT_CST_LT_UNSIGNED (result, offset))
4712 /* G++ 3.2 did not check indirect virtual bases. */
4713 if (abi_version_at_least (2) && include_virtuals_p)
4714 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4715 VEC_iterate (tree, vbases, i, base_binfo); i++)
4717 offset = end_of_base (base_binfo);
4718 if (INT_CST_LT_UNSIGNED (result, offset))
4725 /* Warn about bases of T that are inaccessible because they are
4726 ambiguous. For example:
4729 struct T : public S {};
4730 struct U : public S, public T {};
4732 Here, `(S*) new U' is not allowed because there are two `S'
4736 warn_about_ambiguous_bases (tree t)
4739 VEC(tree,gc) *vbases;
4744 /* If there are no repeated bases, nothing can be ambiguous. */
4745 if (!CLASSTYPE_REPEATED_BASE_P (t))
4748 /* Check direct bases. */
4749 for (binfo = TYPE_BINFO (t), i = 0;
4750 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4752 basetype = BINFO_TYPE (base_binfo);
4754 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4755 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4759 /* Check for ambiguous virtual bases. */
4761 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4762 VEC_iterate (tree, vbases, i, binfo); i++)
4764 basetype = BINFO_TYPE (binfo);
4766 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4767 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4772 /* Compare two INTEGER_CSTs K1 and K2. */
4775 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4777 return tree_int_cst_compare ((tree) k1, (tree) k2);
4780 /* Increase the size indicated in RLI to account for empty classes
4781 that are "off the end" of the class. */
4784 include_empty_classes (record_layout_info rli)
4789 /* It might be the case that we grew the class to allocate a
4790 zero-sized base class. That won't be reflected in RLI, yet,
4791 because we are willing to overlay multiple bases at the same
4792 offset. However, now we need to make sure that RLI is big enough
4793 to reflect the entire class. */
4794 eoc = end_of_class (rli->t,
4795 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4796 rli_size = rli_size_unit_so_far (rli);
4797 if (TREE_CODE (rli_size) == INTEGER_CST
4798 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4800 if (!abi_version_at_least (2))
4801 /* In version 1 of the ABI, the size of a class that ends with
4802 a bitfield was not rounded up to a whole multiple of a
4803 byte. Because rli_size_unit_so_far returns only the number
4804 of fully allocated bytes, any extra bits were not included
4806 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4808 /* The size should have been rounded to a whole byte. */
4809 gcc_assert (tree_int_cst_equal
4810 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4812 = size_binop (PLUS_EXPR,
4814 size_binop (MULT_EXPR,
4815 convert (bitsizetype,
4816 size_binop (MINUS_EXPR,
4818 bitsize_int (BITS_PER_UNIT)));
4819 normalize_rli (rli);
4823 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4824 BINFO_OFFSETs for all of the base-classes. Position the vtable
4825 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4828 layout_class_type (tree t, tree *virtuals_p)
4830 tree non_static_data_members;
4833 record_layout_info rli;
4834 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4835 types that appear at that offset. */
4836 splay_tree empty_base_offsets;
4837 /* True if the last field layed out was a bit-field. */
4838 bool last_field_was_bitfield = false;
4839 /* The location at which the next field should be inserted. */
4841 /* T, as a base class. */
4844 /* Keep track of the first non-static data member. */
4845 non_static_data_members = TYPE_FIELDS (t);
4847 /* Start laying out the record. */
4848 rli = start_record_layout (t);
4850 /* Mark all the primary bases in the hierarchy. */
4851 determine_primary_bases (t);
4853 /* Create a pointer to our virtual function table. */
4854 vptr = create_vtable_ptr (t, virtuals_p);
4856 /* The vptr is always the first thing in the class. */
4859 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4860 TYPE_FIELDS (t) = vptr;
4861 next_field = &TREE_CHAIN (vptr);
4862 place_field (rli, vptr);
4865 next_field = &TYPE_FIELDS (t);
4867 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4868 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4870 build_base_fields (rli, empty_base_offsets, next_field);
4872 /* Layout the non-static data members. */
4873 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4878 /* We still pass things that aren't non-static data members to
4879 the back end, in case it wants to do something with them. */
4880 if (TREE_CODE (field) != FIELD_DECL)
4882 place_field (rli, field);
4883 /* If the static data member has incomplete type, keep track
4884 of it so that it can be completed later. (The handling
4885 of pending statics in finish_record_layout is
4886 insufficient; consider:
4889 struct S2 { static S1 s1; };
4891 At this point, finish_record_layout will be called, but
4892 S1 is still incomplete.) */
4893 if (TREE_CODE (field) == VAR_DECL)
4895 maybe_register_incomplete_var (field);
4896 /* The visibility of static data members is determined
4897 at their point of declaration, not their point of
4899 determine_visibility (field);
4904 type = TREE_TYPE (field);
4905 if (type == error_mark_node)
4908 padding = NULL_TREE;
4910 /* If this field is a bit-field whose width is greater than its
4911 type, then there are some special rules for allocating
4913 if (DECL_C_BIT_FIELD (field)
4914 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4918 bool was_unnamed_p = false;
4919 /* We must allocate the bits as if suitably aligned for the
4920 longest integer type that fits in this many bits. type
4921 of the field. Then, we are supposed to use the left over
4922 bits as additional padding. */
4923 for (itk = itk_char; itk != itk_none; ++itk)
4924 if (INT_CST_LT (DECL_SIZE (field),
4925 TYPE_SIZE (integer_types[itk])))
4928 /* ITK now indicates a type that is too large for the
4929 field. We have to back up by one to find the largest
4931 integer_type = integer_types[itk - 1];
4933 /* Figure out how much additional padding is required. GCC
4934 3.2 always created a padding field, even if it had zero
4936 if (!abi_version_at_least (2)
4937 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4939 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4940 /* In a union, the padding field must have the full width
4941 of the bit-field; all fields start at offset zero. */
4942 padding = DECL_SIZE (field);
4945 if (TREE_CODE (t) == UNION_TYPE)
4946 warning (OPT_Wabi, "size assigned to %qT may not be "
4947 "ABI-compliant and may change in a future "
4950 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4951 TYPE_SIZE (integer_type));
4954 #ifdef PCC_BITFIELD_TYPE_MATTERS
4955 /* An unnamed bitfield does not normally affect the
4956 alignment of the containing class on a target where
4957 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4958 make any exceptions for unnamed bitfields when the
4959 bitfields are longer than their types. Therefore, we
4960 temporarily give the field a name. */
4961 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4963 was_unnamed_p = true;
4964 DECL_NAME (field) = make_anon_name ();
4967 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4968 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4969 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4970 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4971 empty_base_offsets);
4973 DECL_NAME (field) = NULL_TREE;
4974 /* Now that layout has been performed, set the size of the
4975 field to the size of its declared type; the rest of the
4976 field is effectively invisible. */
4977 DECL_SIZE (field) = TYPE_SIZE (type);
4978 /* We must also reset the DECL_MODE of the field. */
4979 if (abi_version_at_least (2))
4980 DECL_MODE (field) = TYPE_MODE (type);
4982 && DECL_MODE (field) != TYPE_MODE (type))
4983 /* Versions of G++ before G++ 3.4 did not reset the
4986 "the offset of %qD may not be ABI-compliant and may "
4987 "change in a future version of GCC", field);
4990 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4991 empty_base_offsets);
4993 /* Remember the location of any empty classes in FIELD. */
4994 if (abi_version_at_least (2))
4995 record_subobject_offsets (TREE_TYPE (field),
4996 byte_position(field),
4998 /*is_data_member=*/true);
5000 /* If a bit-field does not immediately follow another bit-field,
5001 and yet it starts in the middle of a byte, we have failed to
5002 comply with the ABI. */
5004 && DECL_C_BIT_FIELD (field)
5005 /* The TREE_NO_WARNING flag gets set by Objective-C when
5006 laying out an Objective-C class. The ObjC ABI differs
5007 from the C++ ABI, and so we do not want a warning
5009 && !TREE_NO_WARNING (field)
5010 && !last_field_was_bitfield
5011 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5012 DECL_FIELD_BIT_OFFSET (field),
5013 bitsize_unit_node)))
5014 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5015 "change in a future version of GCC", field);
5017 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5018 offset of the field. */
5020 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5021 byte_position (field))
5022 && contains_empty_class_p (TREE_TYPE (field)))
5023 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5024 "classes to be placed at different locations in a "
5025 "future version of GCC", field);
5027 /* The middle end uses the type of expressions to determine the
5028 possible range of expression values. In order to optimize
5029 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5030 must be made aware of the width of "i", via its type.
5032 Because C++ does not have integer types of arbitrary width,
5033 we must (for the purposes of the front end) convert from the
5034 type assigned here to the declared type of the bitfield
5035 whenever a bitfield expression is used as an rvalue.
5036 Similarly, when assigning a value to a bitfield, the value
5037 must be converted to the type given the bitfield here. */
5038 if (DECL_C_BIT_FIELD (field))
5040 unsigned HOST_WIDE_INT width;
5041 tree ftype = TREE_TYPE (field);
5042 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5043 if (width != TYPE_PRECISION (ftype))
5046 = c_build_bitfield_integer_type (width,
5047 TYPE_UNSIGNED (ftype));
5049 = cp_build_qualified_type (TREE_TYPE (field),
5050 TYPE_QUALS (ftype));
5054 /* If we needed additional padding after this field, add it
5060 padding_field = build_decl (input_location,
5064 DECL_BIT_FIELD (padding_field) = 1;
5065 DECL_SIZE (padding_field) = padding;
5066 DECL_CONTEXT (padding_field) = t;
5067 DECL_ARTIFICIAL (padding_field) = 1;
5068 DECL_IGNORED_P (padding_field) = 1;
5069 layout_nonempty_base_or_field (rli, padding_field,
5071 empty_base_offsets);
5074 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5077 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5079 /* Make sure that we are on a byte boundary so that the size of
5080 the class without virtual bases will always be a round number
5082 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5083 normalize_rli (rli);
5086 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5088 if (!abi_version_at_least (2))
5089 include_empty_classes(rli);
5091 /* Delete all zero-width bit-fields from the list of fields. Now
5092 that the type is laid out they are no longer important. */
5093 remove_zero_width_bit_fields (t);
5095 /* Create the version of T used for virtual bases. We do not use
5096 make_class_type for this version; this is an artificial type. For
5097 a POD type, we just reuse T. */
5098 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5100 base_t = make_node (TREE_CODE (t));
5102 /* Set the size and alignment for the new type. In G++ 3.2, all
5103 empty classes were considered to have size zero when used as
5105 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5107 TYPE_SIZE (base_t) = bitsize_zero_node;
5108 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5109 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5111 "layout of classes derived from empty class %qT "
5112 "may change in a future version of GCC",
5119 /* If the ABI version is not at least two, and the last
5120 field was a bit-field, RLI may not be on a byte
5121 boundary. In particular, rli_size_unit_so_far might
5122 indicate the last complete byte, while rli_size_so_far
5123 indicates the total number of bits used. Therefore,
5124 rli_size_so_far, rather than rli_size_unit_so_far, is
5125 used to compute TYPE_SIZE_UNIT. */
5126 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5127 TYPE_SIZE_UNIT (base_t)
5128 = size_binop (MAX_EXPR,
5130 size_binop (CEIL_DIV_EXPR,
5131 rli_size_so_far (rli),
5132 bitsize_int (BITS_PER_UNIT))),
5135 = size_binop (MAX_EXPR,
5136 rli_size_so_far (rli),
5137 size_binop (MULT_EXPR,
5138 convert (bitsizetype, eoc),
5139 bitsize_int (BITS_PER_UNIT)));
5141 TYPE_ALIGN (base_t) = rli->record_align;
5142 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5144 /* Copy the fields from T. */
5145 next_field = &TYPE_FIELDS (base_t);
5146 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5147 if (TREE_CODE (field) == FIELD_DECL)
5149 *next_field = build_decl (input_location,
5153 DECL_CONTEXT (*next_field) = base_t;
5154 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5155 DECL_FIELD_BIT_OFFSET (*next_field)
5156 = DECL_FIELD_BIT_OFFSET (field);
5157 DECL_SIZE (*next_field) = DECL_SIZE (field);
5158 DECL_MODE (*next_field) = DECL_MODE (field);
5159 next_field = &TREE_CHAIN (*next_field);
5162 /* Record the base version of the type. */
5163 CLASSTYPE_AS_BASE (t) = base_t;
5164 TYPE_CONTEXT (base_t) = t;
5167 CLASSTYPE_AS_BASE (t) = t;
5169 /* Every empty class contains an empty class. */
5170 if (CLASSTYPE_EMPTY_P (t))
5171 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5173 /* Set the TYPE_DECL for this type to contain the right
5174 value for DECL_OFFSET, so that we can use it as part
5175 of a COMPONENT_REF for multiple inheritance. */
5176 layout_decl (TYPE_MAIN_DECL (t), 0);
5178 /* Now fix up any virtual base class types that we left lying
5179 around. We must get these done before we try to lay out the
5180 virtual function table. As a side-effect, this will remove the
5181 base subobject fields. */
5182 layout_virtual_bases (rli, empty_base_offsets);
5184 /* Make sure that empty classes are reflected in RLI at this
5186 include_empty_classes(rli);
5188 /* Make sure not to create any structures with zero size. */
5189 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5191 build_decl (input_location,
5192 FIELD_DECL, NULL_TREE, char_type_node));
5194 /* Let the back end lay out the type. */
5195 finish_record_layout (rli, /*free_p=*/true);
5197 /* Warn about bases that can't be talked about due to ambiguity. */
5198 warn_about_ambiguous_bases (t);
5200 /* Now that we're done with layout, give the base fields the real types. */
5201 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5202 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5203 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5206 splay_tree_delete (empty_base_offsets);
5208 if (CLASSTYPE_EMPTY_P (t)
5209 && tree_int_cst_lt (sizeof_biggest_empty_class,
5210 TYPE_SIZE_UNIT (t)))
5211 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5214 /* Determine the "key method" for the class type indicated by TYPE,
5215 and set CLASSTYPE_KEY_METHOD accordingly. */
5218 determine_key_method (tree type)
5222 if (TYPE_FOR_JAVA (type)
5223 || processing_template_decl
5224 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5225 || CLASSTYPE_INTERFACE_KNOWN (type))
5228 /* The key method is the first non-pure virtual function that is not
5229 inline at the point of class definition. On some targets the
5230 key function may not be inline; those targets should not call
5231 this function until the end of the translation unit. */
5232 for (method = TYPE_METHODS (type); method != NULL_TREE;
5233 method = TREE_CHAIN (method))
5234 if (DECL_VINDEX (method) != NULL_TREE
5235 && ! DECL_DECLARED_INLINE_P (method)
5236 && ! DECL_PURE_VIRTUAL_P (method))
5238 CLASSTYPE_KEY_METHOD (type) = method;
5245 /* Perform processing required when the definition of T (a class type)
5249 finish_struct_1 (tree t)
5252 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5253 tree virtuals = NULL_TREE;
5256 if (COMPLETE_TYPE_P (t))
5258 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5259 error ("redefinition of %q#T", t);
5264 /* If this type was previously laid out as a forward reference,
5265 make sure we lay it out again. */
5266 TYPE_SIZE (t) = NULL_TREE;
5267 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5269 /* Make assumptions about the class; we'll reset the flags if
5271 CLASSTYPE_EMPTY_P (t) = 1;
5272 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5273 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5275 /* Do end-of-class semantic processing: checking the validity of the
5276 bases and members and add implicitly generated methods. */
5277 check_bases_and_members (t);
5279 /* Find the key method. */
5280 if (TYPE_CONTAINS_VPTR_P (t))
5282 /* The Itanium C++ ABI permits the key method to be chosen when
5283 the class is defined -- even though the key method so
5284 selected may later turn out to be an inline function. On
5285 some systems (such as ARM Symbian OS) the key method cannot
5286 be determined until the end of the translation unit. On such
5287 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5288 will cause the class to be added to KEYED_CLASSES. Then, in
5289 finish_file we will determine the key method. */
5290 if (targetm.cxx.key_method_may_be_inline ())
5291 determine_key_method (t);
5293 /* If a polymorphic class has no key method, we may emit the vtable
5294 in every translation unit where the class definition appears. */
5295 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5296 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5299 /* Layout the class itself. */
5300 layout_class_type (t, &virtuals);
5301 if (CLASSTYPE_AS_BASE (t) != t)
5302 /* We use the base type for trivial assignments, and hence it
5304 compute_record_mode (CLASSTYPE_AS_BASE (t));
5306 virtuals = modify_all_vtables (t, nreverse (virtuals));
5308 /* If necessary, create the primary vtable for this class. */
5309 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5311 /* We must enter these virtuals into the table. */
5312 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5313 build_primary_vtable (NULL_TREE, t);
5314 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5315 /* Here we know enough to change the type of our virtual
5316 function table, but we will wait until later this function. */
5317 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5320 if (TYPE_CONTAINS_VPTR_P (t))
5325 if (BINFO_VTABLE (TYPE_BINFO (t)))
5326 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5327 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5328 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5330 /* Add entries for virtual functions introduced by this class. */
5331 BINFO_VIRTUALS (TYPE_BINFO (t))
5332 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5334 /* Set DECL_VINDEX for all functions declared in this class. */
5335 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5337 fn = TREE_CHAIN (fn),
5338 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5339 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5341 tree fndecl = BV_FN (fn);
5343 if (DECL_THUNK_P (fndecl))
5344 /* A thunk. We should never be calling this entry directly
5345 from this vtable -- we'd use the entry for the non
5346 thunk base function. */
5347 DECL_VINDEX (fndecl) = NULL_TREE;
5348 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5349 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5353 finish_struct_bits (t);
5355 /* Complete the rtl for any static member objects of the type we're
5357 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5358 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5359 && TREE_TYPE (x) != error_mark_node
5360 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5361 DECL_MODE (x) = TYPE_MODE (t);
5363 /* Done with FIELDS...now decide whether to sort these for
5364 faster lookups later.
5366 We use a small number because most searches fail (succeeding
5367 ultimately as the search bores through the inheritance
5368 hierarchy), and we want this failure to occur quickly. */
5370 n_fields = count_fields (TYPE_FIELDS (t));
5373 struct sorted_fields_type *field_vec = GGC_NEWVAR
5374 (struct sorted_fields_type,
5375 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5376 field_vec->len = n_fields;
5377 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5378 qsort (field_vec->elts, n_fields, sizeof (tree),
5380 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
5383 /* Complain if one of the field types requires lower visibility. */
5384 constrain_class_visibility (t);
5386 /* Make the rtl for any new vtables we have created, and unmark
5387 the base types we marked. */
5390 /* Build the VTT for T. */
5393 /* This warning does not make sense for Java classes, since they
5394 cannot have destructors. */
5395 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5399 dtor = CLASSTYPE_DESTRUCTORS (t);
5400 if (/* An implicitly declared destructor is always public. And,
5401 if it were virtual, we would have created it by now. */
5403 || (!DECL_VINDEX (dtor)
5404 && (/* public non-virtual */
5405 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5406 || (/* non-public non-virtual with friends */
5407 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5408 && (CLASSTYPE_FRIEND_CLASSES (t)
5409 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5410 warning (OPT_Wnon_virtual_dtor,
5411 "%q#T has virtual functions and accessible"
5412 " non-virtual destructor", t);
5417 if (warn_overloaded_virtual)
5420 /* Class layout, assignment of virtual table slots, etc., is now
5421 complete. Give the back end a chance to tweak the visibility of
5422 the class or perform any other required target modifications. */
5423 targetm.cxx.adjust_class_at_definition (t);
5425 maybe_suppress_debug_info (t);
5427 dump_class_hierarchy (t);
5429 /* Finish debugging output for this type. */
5430 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5433 /* When T was built up, the member declarations were added in reverse
5434 order. Rearrange them to declaration order. */
5437 unreverse_member_declarations (tree t)
5443 /* The following lists are all in reverse order. Put them in
5444 declaration order now. */
5445 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5446 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5448 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5449 reverse order, so we can't just use nreverse. */
5451 for (x = TYPE_FIELDS (t);
5452 x && TREE_CODE (x) != TYPE_DECL;
5455 next = TREE_CHAIN (x);
5456 TREE_CHAIN (x) = prev;
5461 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5463 TYPE_FIELDS (t) = prev;
5468 finish_struct (tree t, tree attributes)
5470 location_t saved_loc = input_location;
5472 /* Now that we've got all the field declarations, reverse everything
5474 unreverse_member_declarations (t);
5476 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5478 /* Nadger the current location so that diagnostics point to the start of
5479 the struct, not the end. */
5480 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5482 if (processing_template_decl)
5486 finish_struct_methods (t);
5487 TYPE_SIZE (t) = bitsize_zero_node;
5488 TYPE_SIZE_UNIT (t) = size_zero_node;
5490 /* We need to emit an error message if this type was used as a parameter
5491 and it is an abstract type, even if it is a template. We construct
5492 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5493 account and we call complete_vars with this type, which will check
5494 the PARM_DECLS. Note that while the type is being defined,
5495 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5496 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5497 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5498 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5499 if (DECL_PURE_VIRTUAL_P (x))
5500 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5504 finish_struct_1 (t);
5506 input_location = saved_loc;
5508 TYPE_BEING_DEFINED (t) = 0;
5510 if (current_class_type)
5513 error ("trying to finish struct, but kicked out due to previous parse errors");
5515 if (processing_template_decl && at_function_scope_p ())
5516 add_stmt (build_min (TAG_DEFN, t));
5521 /* Return the dynamic type of INSTANCE, if known.
5522 Used to determine whether the virtual function table is needed
5525 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5526 of our knowledge of its type. *NONNULL should be initialized
5527 before this function is called. */
5530 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5532 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5534 switch (TREE_CODE (instance))
5537 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5540 return RECUR (TREE_OPERAND (instance, 0));
5543 /* This is a call to a constructor, hence it's never zero. */
5544 if (TREE_HAS_CONSTRUCTOR (instance))
5548 return TREE_TYPE (instance);
5553 /* This is a call to a constructor, hence it's never zero. */
5554 if (TREE_HAS_CONSTRUCTOR (instance))
5558 return TREE_TYPE (instance);
5560 return RECUR (TREE_OPERAND (instance, 0));
5562 case POINTER_PLUS_EXPR:
5565 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5566 return RECUR (TREE_OPERAND (instance, 0));
5567 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5568 /* Propagate nonnull. */
5569 return RECUR (TREE_OPERAND (instance, 0));
5574 return RECUR (TREE_OPERAND (instance, 0));
5577 instance = TREE_OPERAND (instance, 0);
5580 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5581 with a real object -- given &p->f, p can still be null. */
5582 tree t = get_base_address (instance);
5583 /* ??? Probably should check DECL_WEAK here. */
5584 if (t && DECL_P (t))
5587 return RECUR (instance);
5590 /* If this component is really a base class reference, then the field
5591 itself isn't definitive. */
5592 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5593 return RECUR (TREE_OPERAND (instance, 0));
5594 return RECUR (TREE_OPERAND (instance, 1));
5598 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5599 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
5603 return TREE_TYPE (TREE_TYPE (instance));
5605 /* fall through... */
5609 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
5613 return TREE_TYPE (instance);
5615 else if (instance == current_class_ptr)
5620 /* if we're in a ctor or dtor, we know our type. */
5621 if (DECL_LANG_SPECIFIC (current_function_decl)
5622 && (DECL_CONSTRUCTOR_P (current_function_decl)
5623 || DECL_DESTRUCTOR_P (current_function_decl)))
5627 return TREE_TYPE (TREE_TYPE (instance));
5630 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5632 /* We only need one hash table because it is always left empty. */
5635 ht = htab_create (37,
5640 /* Reference variables should be references to objects. */
5644 /* Enter the INSTANCE in a table to prevent recursion; a
5645 variable's initializer may refer to the variable
5647 if (TREE_CODE (instance) == VAR_DECL
5648 && DECL_INITIAL (instance)
5649 && !htab_find (ht, instance))
5654 slot = htab_find_slot (ht, instance, INSERT);
5656 type = RECUR (DECL_INITIAL (instance));
5657 htab_remove_elt (ht, instance);
5670 /* Return nonzero if the dynamic type of INSTANCE is known, and
5671 equivalent to the static type. We also handle the case where
5672 INSTANCE is really a pointer. Return negative if this is a
5673 ctor/dtor. There the dynamic type is known, but this might not be
5674 the most derived base of the original object, and hence virtual
5675 bases may not be layed out according to this type.
5677 Used to determine whether the virtual function table is needed
5680 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5681 of our knowledge of its type. *NONNULL should be initialized
5682 before this function is called. */
5685 resolves_to_fixed_type_p (tree instance, int* nonnull)
5687 tree t = TREE_TYPE (instance);
5689 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5690 if (fixed == NULL_TREE)
5692 if (POINTER_TYPE_P (t))
5694 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5696 return cdtorp ? -1 : 1;
5701 init_class_processing (void)
5703 current_class_depth = 0;
5704 current_class_stack_size = 10;
5706 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5707 local_classes = VEC_alloc (tree, gc, 8);
5708 sizeof_biggest_empty_class = size_zero_node;
5710 ridpointers[(int) RID_PUBLIC] = access_public_node;
5711 ridpointers[(int) RID_PRIVATE] = access_private_node;
5712 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5715 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5718 restore_class_cache (void)
5722 /* We are re-entering the same class we just left, so we don't
5723 have to search the whole inheritance matrix to find all the
5724 decls to bind again. Instead, we install the cached
5725 class_shadowed list and walk through it binding names. */
5726 push_binding_level (previous_class_level);
5727 class_binding_level = previous_class_level;
5728 /* Restore IDENTIFIER_TYPE_VALUE. */
5729 for (type = class_binding_level->type_shadowed;
5731 type = TREE_CHAIN (type))
5732 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5735 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5736 appropriate for TYPE.
5738 So that we may avoid calls to lookup_name, we cache the _TYPE
5739 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5741 For multiple inheritance, we perform a two-pass depth-first search
5742 of the type lattice. */
5745 pushclass (tree type)
5747 class_stack_node_t csn;
5749 type = TYPE_MAIN_VARIANT (type);
5751 /* Make sure there is enough room for the new entry on the stack. */
5752 if (current_class_depth + 1 >= current_class_stack_size)
5754 current_class_stack_size *= 2;
5756 = XRESIZEVEC (struct class_stack_node, current_class_stack,
5757 current_class_stack_size);
5760 /* Insert a new entry on the class stack. */
5761 csn = current_class_stack + current_class_depth;
5762 csn->name = current_class_name;
5763 csn->type = current_class_type;
5764 csn->access = current_access_specifier;
5765 csn->names_used = 0;
5767 current_class_depth++;
5769 /* Now set up the new type. */
5770 current_class_name = TYPE_NAME (type);
5771 if (TREE_CODE (current_class_name) == TYPE_DECL)
5772 current_class_name = DECL_NAME (current_class_name);
5773 current_class_type = type;
5775 /* By default, things in classes are private, while things in
5776 structures or unions are public. */
5777 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5778 ? access_private_node
5779 : access_public_node);
5781 if (previous_class_level
5782 && type != previous_class_level->this_entity
5783 && current_class_depth == 1)
5785 /* Forcibly remove any old class remnants. */
5786 invalidate_class_lookup_cache ();
5789 if (!previous_class_level
5790 || type != previous_class_level->this_entity
5791 || current_class_depth > 1)
5794 restore_class_cache ();
5797 /* When we exit a toplevel class scope, we save its binding level so
5798 that we can restore it quickly. Here, we've entered some other
5799 class, so we must invalidate our cache. */
5802 invalidate_class_lookup_cache (void)
5804 previous_class_level = NULL;
5807 /* Get out of the current class scope. If we were in a class scope
5808 previously, that is the one popped to. */
5815 current_class_depth--;
5816 current_class_name = current_class_stack[current_class_depth].name;
5817 current_class_type = current_class_stack[current_class_depth].type;
5818 current_access_specifier = current_class_stack[current_class_depth].access;
5819 if (current_class_stack[current_class_depth].names_used)
5820 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5823 /* Mark the top of the class stack as hidden. */
5826 push_class_stack (void)
5828 if (current_class_depth)
5829 ++current_class_stack[current_class_depth - 1].hidden;
5832 /* Mark the top of the class stack as un-hidden. */
5835 pop_class_stack (void)
5837 if (current_class_depth)
5838 --current_class_stack[current_class_depth - 1].hidden;
5841 /* Returns 1 if the class type currently being defined is either T or
5842 a nested type of T. */
5845 currently_open_class (tree t)
5849 if (!CLASS_TYPE_P (t))
5852 /* We start looking from 1 because entry 0 is from global scope,
5854 for (i = current_class_depth; i > 0; --i)
5857 if (i == current_class_depth)
5858 c = current_class_type;
5861 if (current_class_stack[i].hidden)
5863 c = current_class_stack[i].type;
5867 if (same_type_p (c, t))
5873 /* If either current_class_type or one of its enclosing classes are derived
5874 from T, return the appropriate type. Used to determine how we found
5875 something via unqualified lookup. */
5878 currently_open_derived_class (tree t)
5882 /* The bases of a dependent type are unknown. */
5883 if (dependent_type_p (t))
5886 if (!current_class_type)
5889 if (DERIVED_FROM_P (t, current_class_type))
5890 return current_class_type;
5892 for (i = current_class_depth - 1; i > 0; --i)
5894 if (current_class_stack[i].hidden)
5896 if (DERIVED_FROM_P (t, current_class_stack[i].type))
5897 return current_class_stack[i].type;
5903 /* When entering a class scope, all enclosing class scopes' names with
5904 static meaning (static variables, static functions, types and
5905 enumerators) have to be visible. This recursive function calls
5906 pushclass for all enclosing class contexts until global or a local
5907 scope is reached. TYPE is the enclosed class. */
5910 push_nested_class (tree type)
5912 /* A namespace might be passed in error cases, like A::B:C. */
5913 if (type == NULL_TREE
5914 || !CLASS_TYPE_P (type))
5917 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
5922 /* Undoes a push_nested_class call. */
5925 pop_nested_class (void)
5927 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5930 if (context && CLASS_TYPE_P (context))
5931 pop_nested_class ();
5934 /* Returns the number of extern "LANG" blocks we are nested within. */
5937 current_lang_depth (void)
5939 return VEC_length (tree, current_lang_base);
5942 /* Set global variables CURRENT_LANG_NAME to appropriate value
5943 so that behavior of name-mangling machinery is correct. */
5946 push_lang_context (tree name)
5948 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
5950 if (name == lang_name_cplusplus)
5952 current_lang_name = name;
5954 else if (name == lang_name_java)
5956 current_lang_name = name;
5957 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5958 (See record_builtin_java_type in decl.c.) However, that causes
5959 incorrect debug entries if these types are actually used.
5960 So we re-enable debug output after extern "Java". */
5961 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
5962 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
5963 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
5964 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
5965 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
5966 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
5967 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
5968 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
5970 else if (name == lang_name_c)
5972 current_lang_name = name;
5975 error ("language string %<\"%E\"%> not recognized", name);
5978 /* Get out of the current language scope. */
5981 pop_lang_context (void)
5983 current_lang_name = VEC_pop (tree, current_lang_base);
5986 /* Type instantiation routines. */
5988 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
5989 matches the TARGET_TYPE. If there is no satisfactory match, return
5990 error_mark_node, and issue an error & warning messages under
5991 control of FLAGS. Permit pointers to member function if FLAGS
5992 permits. If TEMPLATE_ONLY, the name of the overloaded function was
5993 a template-id, and EXPLICIT_TARGS are the explicitly provided
5996 If OVERLOAD is for one or more member functions, then ACCESS_PATH
5997 is the base path used to reference those member functions. If
5998 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
5999 resolved to a member function, access checks will be performed and
6000 errors issued if appropriate. */
6003 resolve_address_of_overloaded_function (tree target_type,
6005 tsubst_flags_t flags,
6007 tree explicit_targs,
6010 /* Here's what the standard says:
6014 If the name is a function template, template argument deduction
6015 is done, and if the argument deduction succeeds, the deduced
6016 arguments are used to generate a single template function, which
6017 is added to the set of overloaded functions considered.
6019 Non-member functions and static member functions match targets of
6020 type "pointer-to-function" or "reference-to-function." Nonstatic
6021 member functions match targets of type "pointer-to-member
6022 function;" the function type of the pointer to member is used to
6023 select the member function from the set of overloaded member
6024 functions. If a nonstatic member function is selected, the
6025 reference to the overloaded function name is required to have the
6026 form of a pointer to member as described in 5.3.1.
6028 If more than one function is selected, any template functions in
6029 the set are eliminated if the set also contains a non-template
6030 function, and any given template function is eliminated if the
6031 set contains a second template function that is more specialized
6032 than the first according to the partial ordering rules 14.5.5.2.
6033 After such eliminations, if any, there shall remain exactly one
6034 selected function. */
6037 int is_reference = 0;
6038 /* We store the matches in a TREE_LIST rooted here. The functions
6039 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6040 interoperability with most_specialized_instantiation. */
6041 tree matches = NULL_TREE;
6044 /* By the time we get here, we should be seeing only real
6045 pointer-to-member types, not the internal POINTER_TYPE to
6046 METHOD_TYPE representation. */
6047 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6048 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6050 gcc_assert (is_overloaded_fn (overload));
6052 /* Check that the TARGET_TYPE is reasonable. */
6053 if (TYPE_PTRFN_P (target_type))
6055 else if (TYPE_PTRMEMFUNC_P (target_type))
6056 /* This is OK, too. */
6058 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6060 /* This is OK, too. This comes from a conversion to reference
6062 target_type = build_reference_type (target_type);
6067 if (flags & tf_error)
6068 error ("cannot resolve overloaded function %qD based on"
6069 " conversion to type %qT",
6070 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6071 return error_mark_node;
6074 /* If we can find a non-template function that matches, we can just
6075 use it. There's no point in generating template instantiations
6076 if we're just going to throw them out anyhow. But, of course, we
6077 can only do this when we don't *need* a template function. */
6082 for (fns = overload; fns; fns = OVL_NEXT (fns))
6084 tree fn = OVL_CURRENT (fns);
6087 if (TREE_CODE (fn) == TEMPLATE_DECL)
6088 /* We're not looking for templates just yet. */
6091 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6093 /* We're looking for a non-static member, and this isn't
6094 one, or vice versa. */
6097 /* Ignore functions which haven't been explicitly
6099 if (DECL_ANTICIPATED (fn))
6102 /* See if there's a match. */
6103 fntype = TREE_TYPE (fn);
6105 fntype = build_ptrmemfunc_type (build_pointer_type (fntype));
6106 else if (!is_reference)
6107 fntype = build_pointer_type (fntype);
6109 if (can_convert_arg (target_type, fntype, fn, LOOKUP_NORMAL))
6110 matches = tree_cons (fn, NULL_TREE, matches);
6114 /* Now, if we've already got a match (or matches), there's no need
6115 to proceed to the template functions. But, if we don't have a
6116 match we need to look at them, too. */
6119 tree target_fn_type;
6120 tree target_arg_types;
6121 tree target_ret_type;
6124 unsigned int nargs, ia;
6129 = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (target_type));
6131 target_fn_type = TREE_TYPE (target_type);
6132 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6133 target_ret_type = TREE_TYPE (target_fn_type);
6135 /* Never do unification on the 'this' parameter. */
6136 if (TREE_CODE (target_fn_type) == METHOD_TYPE)
6137 target_arg_types = TREE_CHAIN (target_arg_types);
6139 nargs = list_length (target_arg_types);
6140 args = XALLOCAVEC (tree, nargs);
6141 for (arg = target_arg_types, ia = 0;
6142 arg != NULL_TREE && arg != void_list_node;
6143 arg = TREE_CHAIN (arg), ++ia)
6144 args[ia] = TREE_VALUE (arg);
6147 for (fns = overload; fns; fns = OVL_NEXT (fns))
6149 tree fn = OVL_CURRENT (fns);
6151 tree instantiation_type;
6154 if (TREE_CODE (fn) != TEMPLATE_DECL)
6155 /* We're only looking for templates. */
6158 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6160 /* We're not looking for a non-static member, and this is
6161 one, or vice versa. */
6164 /* Try to do argument deduction. */
6165 targs = make_tree_vec (DECL_NTPARMS (fn));
6166 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6167 target_ret_type, DEDUCE_EXACT,
6169 /* Argument deduction failed. */
6172 /* Instantiate the template. */
6173 instantiation = instantiate_template (fn, targs, flags);
6174 if (instantiation == error_mark_node)
6175 /* Instantiation failed. */
6178 /* See if there's a match. */
6179 instantiation_type = TREE_TYPE (instantiation);
6181 instantiation_type =
6182 build_ptrmemfunc_type (build_pointer_type (instantiation_type));
6183 else if (!is_reference)
6184 instantiation_type = build_pointer_type (instantiation_type);
6185 if (can_convert_arg (target_type, instantiation_type, instantiation,
6187 matches = tree_cons (instantiation, fn, matches);
6190 /* Now, remove all but the most specialized of the matches. */
6193 tree match = most_specialized_instantiation (matches);
6195 if (match != error_mark_node)
6196 matches = tree_cons (TREE_PURPOSE (match),
6202 /* Now we should have exactly one function in MATCHES. */
6203 if (matches == NULL_TREE)
6205 /* There were *no* matches. */
6206 if (flags & tf_error)
6208 error ("no matches converting function %qD to type %q#T",
6209 DECL_NAME (OVL_CURRENT (overload)),
6212 /* print_candidates expects a chain with the functions in
6213 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6214 so why be clever?). */
6215 for (; overload; overload = OVL_NEXT (overload))
6216 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
6219 print_candidates (matches);
6221 return error_mark_node;
6223 else if (TREE_CHAIN (matches))
6225 /* There were too many matches. First check if they're all
6226 the same function. */
6229 fn = TREE_PURPOSE (matches);
6230 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6231 if (!decls_match (fn, TREE_PURPOSE (match)))
6236 if (flags & tf_error)
6238 error ("converting overloaded function %qD to type %q#T is ambiguous",
6239 DECL_NAME (OVL_FUNCTION (overload)),
6242 /* Since print_candidates expects the functions in the
6243 TREE_VALUE slot, we flip them here. */
6244 for (match = matches; match; match = TREE_CHAIN (match))
6245 TREE_VALUE (match) = TREE_PURPOSE (match);
6247 print_candidates (matches);
6250 return error_mark_node;
6254 /* Good, exactly one match. Now, convert it to the correct type. */
6255 fn = TREE_PURPOSE (matches);
6257 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6258 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6260 static int explained;
6262 if (!(flags & tf_error))
6263 return error_mark_node;
6265 permerror (input_location, "assuming pointer to member %qD", fn);
6268 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6273 /* If we're doing overload resolution purely for the purpose of
6274 determining conversion sequences, we should not consider the
6275 function used. If this conversion sequence is selected, the
6276 function will be marked as used at this point. */
6277 if (!(flags & tf_conv))
6279 /* Make =delete work with SFINAE. */
6280 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6281 return error_mark_node;
6286 /* We could not check access to member functions when this
6287 expression was originally created since we did not know at that
6288 time to which function the expression referred. */
6289 if (!(flags & tf_no_access_control)
6290 && DECL_FUNCTION_MEMBER_P (fn))
6292 gcc_assert (access_path);
6293 perform_or_defer_access_check (access_path, fn, fn);
6296 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6297 return cp_build_unary_op (ADDR_EXPR, fn, 0, flags);
6300 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6301 will mark the function as addressed, but here we must do it
6303 cxx_mark_addressable (fn);
6309 /* This function will instantiate the type of the expression given in
6310 RHS to match the type of LHSTYPE. If errors exist, then return
6311 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6312 we complain on errors. If we are not complaining, never modify rhs,
6313 as overload resolution wants to try many possible instantiations, in
6314 the hope that at least one will work.
6316 For non-recursive calls, LHSTYPE should be a function, pointer to
6317 function, or a pointer to member function. */
6320 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6322 tsubst_flags_t flags_in = flags;
6323 tree access_path = NULL_TREE;
6325 flags &= ~tf_ptrmem_ok;
6327 if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
6329 if (flags & tf_error)
6330 error ("not enough type information");
6331 return error_mark_node;
6334 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6336 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6338 if (flag_ms_extensions
6339 && TYPE_PTRMEMFUNC_P (lhstype)
6340 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6341 /* Microsoft allows `A::f' to be resolved to a
6342 pointer-to-member. */
6346 if (flags & tf_error)
6347 error ("argument of type %qT does not match %qT",
6348 TREE_TYPE (rhs), lhstype);
6349 return error_mark_node;
6353 if (TREE_CODE (rhs) == BASELINK)
6355 access_path = BASELINK_ACCESS_BINFO (rhs);
6356 rhs = BASELINK_FUNCTIONS (rhs);
6359 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6360 deduce any type information. */
6361 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6363 if (flags & tf_error)
6364 error ("not enough type information");
6365 return error_mark_node;
6368 /* There only a few kinds of expressions that may have a type
6369 dependent on overload resolution. */
6370 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6371 || TREE_CODE (rhs) == COMPONENT_REF
6372 || really_overloaded_fn (rhs)
6373 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
6375 /* This should really only be used when attempting to distinguish
6376 what sort of a pointer to function we have. For now, any
6377 arithmetic operation which is not supported on pointers
6378 is rejected as an error. */
6380 switch (TREE_CODE (rhs))
6384 tree member = TREE_OPERAND (rhs, 1);
6386 member = instantiate_type (lhstype, member, flags);
6387 if (member != error_mark_node
6388 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6389 /* Do not lose object's side effects. */
6390 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6391 TREE_OPERAND (rhs, 0), member);
6396 rhs = TREE_OPERAND (rhs, 1);
6397 if (BASELINK_P (rhs))
6398 return instantiate_type (lhstype, rhs, flags_in);
6400 /* This can happen if we are forming a pointer-to-member for a
6402 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6406 case TEMPLATE_ID_EXPR:
6408 tree fns = TREE_OPERAND (rhs, 0);
6409 tree args = TREE_OPERAND (rhs, 1);
6412 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6413 /*template_only=*/true,
6420 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6421 /*template_only=*/false,
6422 /*explicit_targs=*/NULL_TREE,
6427 if (PTRMEM_OK_P (rhs))
6428 flags |= tf_ptrmem_ok;
6430 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6434 return error_mark_node;
6439 return error_mark_node;
6442 /* Return the name of the virtual function pointer field
6443 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6444 this may have to look back through base types to find the
6445 ultimate field name. (For single inheritance, these could
6446 all be the same name. Who knows for multiple inheritance). */
6449 get_vfield_name (tree type)
6451 tree binfo, base_binfo;
6454 for (binfo = TYPE_BINFO (type);
6455 BINFO_N_BASE_BINFOS (binfo);
6458 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6460 if (BINFO_VIRTUAL_P (base_binfo)
6461 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6465 type = BINFO_TYPE (binfo);
6466 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6467 + TYPE_NAME_LENGTH (type) + 2);
6468 sprintf (buf, VFIELD_NAME_FORMAT,
6469 IDENTIFIER_POINTER (constructor_name (type)));
6470 return get_identifier (buf);
6474 print_class_statistics (void)
6476 #ifdef GATHER_STATISTICS
6477 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6478 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6481 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6482 n_vtables, n_vtable_searches);
6483 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6484 n_vtable_entries, n_vtable_elems);
6489 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6490 according to [class]:
6491 The class-name is also inserted
6492 into the scope of the class itself. For purposes of access checking,
6493 the inserted class name is treated as if it were a public member name. */
6496 build_self_reference (void)
6498 tree name = constructor_name (current_class_type);
6499 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6502 DECL_NONLOCAL (value) = 1;
6503 DECL_CONTEXT (value) = current_class_type;
6504 DECL_ARTIFICIAL (value) = 1;
6505 SET_DECL_SELF_REFERENCE_P (value);
6507 if (processing_template_decl)
6508 value = push_template_decl (value);
6510 saved_cas = current_access_specifier;
6511 current_access_specifier = access_public_node;
6512 finish_member_declaration (value);
6513 current_access_specifier = saved_cas;
6516 /* Returns 1 if TYPE contains only padding bytes. */
6519 is_empty_class (tree type)
6521 if (type == error_mark_node)
6524 if (! CLASS_TYPE_P (type))
6527 /* In G++ 3.2, whether or not a class was empty was determined by
6528 looking at its size. */
6529 if (abi_version_at_least (2))
6530 return CLASSTYPE_EMPTY_P (type);
6532 return integer_zerop (CLASSTYPE_SIZE (type));
6535 /* Returns true if TYPE contains an empty class. */
6538 contains_empty_class_p (tree type)
6540 if (is_empty_class (type))
6542 if (CLASS_TYPE_P (type))
6549 for (binfo = TYPE_BINFO (type), i = 0;
6550 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6551 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6553 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6554 if (TREE_CODE (field) == FIELD_DECL
6555 && !DECL_ARTIFICIAL (field)
6556 && is_empty_class (TREE_TYPE (field)))
6559 else if (TREE_CODE (type) == ARRAY_TYPE)
6560 return contains_empty_class_p (TREE_TYPE (type));
6564 /* Returns true if TYPE contains no actual data, just various
6565 possible combinations of empty classes. */
6568 is_really_empty_class (tree type)
6570 if (is_empty_class (type))
6572 if (CLASS_TYPE_P (type))
6579 for (binfo = TYPE_BINFO (type), i = 0;
6580 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6581 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
6583 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6584 if (TREE_CODE (field) == FIELD_DECL
6585 && !DECL_ARTIFICIAL (field)
6586 && !is_really_empty_class (TREE_TYPE (field)))
6590 else if (TREE_CODE (type) == ARRAY_TYPE)
6591 return is_really_empty_class (TREE_TYPE (type));
6595 /* Note that NAME was looked up while the current class was being
6596 defined and that the result of that lookup was DECL. */
6599 maybe_note_name_used_in_class (tree name, tree decl)
6601 splay_tree names_used;
6603 /* If we're not defining a class, there's nothing to do. */
6604 if (!(innermost_scope_kind() == sk_class
6605 && TYPE_BEING_DEFINED (current_class_type)))
6608 /* If there's already a binding for this NAME, then we don't have
6609 anything to worry about. */
6610 if (lookup_member (current_class_type, name,
6611 /*protect=*/0, /*want_type=*/false))
6614 if (!current_class_stack[current_class_depth - 1].names_used)
6615 current_class_stack[current_class_depth - 1].names_used
6616 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6617 names_used = current_class_stack[current_class_depth - 1].names_used;
6619 splay_tree_insert (names_used,
6620 (splay_tree_key) name,
6621 (splay_tree_value) decl);
6624 /* Note that NAME was declared (as DECL) in the current class. Check
6625 to see that the declaration is valid. */
6628 note_name_declared_in_class (tree name, tree decl)
6630 splay_tree names_used;
6633 /* Look to see if we ever used this name. */
6635 = current_class_stack[current_class_depth - 1].names_used;
6639 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6642 /* [basic.scope.class]
6644 A name N used in a class S shall refer to the same declaration
6645 in its context and when re-evaluated in the completed scope of
6647 permerror (input_location, "declaration of %q#D", decl);
6648 permerror (input_location, "changes meaning of %qD from %q+#D",
6649 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6653 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6654 Secondary vtables are merged with primary vtables; this function
6655 will return the VAR_DECL for the primary vtable. */
6658 get_vtbl_decl_for_binfo (tree binfo)
6662 decl = BINFO_VTABLE (binfo);
6663 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
6665 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6666 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6669 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6674 /* Returns the binfo for the primary base of BINFO. If the resulting
6675 BINFO is a virtual base, and it is inherited elsewhere in the
6676 hierarchy, then the returned binfo might not be the primary base of
6677 BINFO in the complete object. Check BINFO_PRIMARY_P or
6678 BINFO_LOST_PRIMARY_P to be sure. */
6681 get_primary_binfo (tree binfo)
6685 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6689 return copied_binfo (primary_base, binfo);
6692 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6695 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6698 fprintf (stream, "%*s", indent, "");
6702 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6703 INDENT should be zero when called from the top level; it is
6704 incremented recursively. IGO indicates the next expected BINFO in
6705 inheritance graph ordering. */
6708 dump_class_hierarchy_r (FILE *stream,
6718 indented = maybe_indent_hierarchy (stream, indent, 0);
6719 fprintf (stream, "%s (0x%lx) ",
6720 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6721 (unsigned long) binfo);
6724 fprintf (stream, "alternative-path\n");
6727 igo = TREE_CHAIN (binfo);
6729 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6730 tree_low_cst (BINFO_OFFSET (binfo), 0));
6731 if (is_empty_class (BINFO_TYPE (binfo)))
6732 fprintf (stream, " empty");
6733 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6734 fprintf (stream, " nearly-empty");
6735 if (BINFO_VIRTUAL_P (binfo))
6736 fprintf (stream, " virtual");
6737 fprintf (stream, "\n");
6740 if (BINFO_PRIMARY_P (binfo))
6742 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6743 fprintf (stream, " primary-for %s (0x%lx)",
6744 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6745 TFF_PLAIN_IDENTIFIER),
6746 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6748 if (BINFO_LOST_PRIMARY_P (binfo))
6750 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6751 fprintf (stream, " lost-primary");
6754 fprintf (stream, "\n");
6756 if (!(flags & TDF_SLIM))
6760 if (BINFO_SUBVTT_INDEX (binfo))
6762 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6763 fprintf (stream, " subvttidx=%s",
6764 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6765 TFF_PLAIN_IDENTIFIER));
6767 if (BINFO_VPTR_INDEX (binfo))
6769 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6770 fprintf (stream, " vptridx=%s",
6771 expr_as_string (BINFO_VPTR_INDEX (binfo),
6772 TFF_PLAIN_IDENTIFIER));
6774 if (BINFO_VPTR_FIELD (binfo))
6776 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6777 fprintf (stream, " vbaseoffset=%s",
6778 expr_as_string (BINFO_VPTR_FIELD (binfo),
6779 TFF_PLAIN_IDENTIFIER));
6781 if (BINFO_VTABLE (binfo))
6783 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6784 fprintf (stream, " vptr=%s",
6785 expr_as_string (BINFO_VTABLE (binfo),
6786 TFF_PLAIN_IDENTIFIER));
6790 fprintf (stream, "\n");
6793 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6794 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6799 /* Dump the BINFO hierarchy for T. */
6802 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6804 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6805 fprintf (stream, " size=%lu align=%lu\n",
6806 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6807 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6808 fprintf (stream, " base size=%lu base align=%lu\n",
6809 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6811 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6813 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6814 fprintf (stream, "\n");
6817 /* Debug interface to hierarchy dumping. */
6820 debug_class (tree t)
6822 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6826 dump_class_hierarchy (tree t)
6829 FILE *stream = dump_begin (TDI_class, &flags);
6833 dump_class_hierarchy_1 (stream, flags, t);
6834 dump_end (TDI_class, stream);
6839 dump_array (FILE * stream, tree decl)
6842 unsigned HOST_WIDE_INT ix;
6844 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6846 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6848 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6849 fprintf (stream, " %s entries",
6850 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6851 TFF_PLAIN_IDENTIFIER));
6852 fprintf (stream, "\n");
6854 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
6856 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
6857 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
6861 dump_vtable (tree t, tree binfo, tree vtable)
6864 FILE *stream = dump_begin (TDI_class, &flags);
6869 if (!(flags & TDF_SLIM))
6871 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6873 fprintf (stream, "%s for %s",
6874 ctor_vtbl_p ? "Construction vtable" : "Vtable",
6875 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6878 if (!BINFO_VIRTUAL_P (binfo))
6879 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6880 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6882 fprintf (stream, "\n");
6883 dump_array (stream, vtable);
6884 fprintf (stream, "\n");
6887 dump_end (TDI_class, stream);
6891 dump_vtt (tree t, tree vtt)
6894 FILE *stream = dump_begin (TDI_class, &flags);
6899 if (!(flags & TDF_SLIM))
6901 fprintf (stream, "VTT for %s\n",
6902 type_as_string (t, TFF_PLAIN_IDENTIFIER));
6903 dump_array (stream, vtt);
6904 fprintf (stream, "\n");
6907 dump_end (TDI_class, stream);
6910 /* Dump a function or thunk and its thunkees. */
6913 dump_thunk (FILE *stream, int indent, tree thunk)
6915 static const char spaces[] = " ";
6916 tree name = DECL_NAME (thunk);
6919 fprintf (stream, "%.*s%p %s %s", indent, spaces,
6921 !DECL_THUNK_P (thunk) ? "function"
6922 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6923 name ? IDENTIFIER_POINTER (name) : "<unset>");
6924 if (DECL_THUNK_P (thunk))
6926 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6927 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6929 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6930 if (!virtual_adjust)
6932 else if (DECL_THIS_THUNK_P (thunk))
6933 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
6934 tree_low_cst (virtual_adjust, 0));
6936 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6937 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6938 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6939 if (THUNK_ALIAS (thunk))
6940 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6942 fprintf (stream, "\n");
6943 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6944 dump_thunk (stream, indent + 2, thunks);
6947 /* Dump the thunks for FN. */
6950 debug_thunks (tree fn)
6952 dump_thunk (stderr, 0, fn);
6955 /* Virtual function table initialization. */
6957 /* Create all the necessary vtables for T and its base classes. */
6960 finish_vtbls (tree t)
6965 /* We lay out the primary and secondary vtables in one contiguous
6966 vtable. The primary vtable is first, followed by the non-virtual
6967 secondary vtables in inheritance graph order. */
6968 list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6969 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6970 TYPE_BINFO (t), t, list);
6972 /* Then come the virtual bases, also in inheritance graph order. */
6973 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6975 if (!BINFO_VIRTUAL_P (vbase))
6977 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6980 if (BINFO_VTABLE (TYPE_BINFO (t)))
6981 initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
6984 /* Initialize the vtable for BINFO with the INITS. */
6987 initialize_vtable (tree binfo, tree inits)
6991 layout_vtable_decl (binfo, list_length (inits));
6992 decl = get_vtbl_decl_for_binfo (binfo);
6993 initialize_artificial_var (decl, inits);
6994 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
6997 /* Build the VTT (virtual table table) for T.
6998 A class requires a VTT if it has virtual bases.
7001 1 - primary virtual pointer for complete object T
7002 2 - secondary VTTs for each direct non-virtual base of T which requires a
7004 3 - secondary virtual pointers for each direct or indirect base of T which
7005 has virtual bases or is reachable via a virtual path from T.
7006 4 - secondary VTTs for each direct or indirect virtual base of T.
7008 Secondary VTTs look like complete object VTTs without part 4. */
7018 /* Build up the initializers for the VTT. */
7020 index = size_zero_node;
7021 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7023 /* If we didn't need a VTT, we're done. */
7027 /* Figure out the type of the VTT. */
7028 type = build_index_type (size_int (list_length (inits) - 1));
7029 type = build_cplus_array_type (const_ptr_type_node, type);
7031 /* Now, build the VTT object itself. */
7032 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7033 initialize_artificial_var (vtt, inits);
7034 /* Add the VTT to the vtables list. */
7035 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
7036 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7041 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7042 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7043 and CHAIN the vtable pointer for this binfo after construction is
7044 complete. VALUE can also be another BINFO, in which case we recurse. */
7047 binfo_ctor_vtable (tree binfo)
7053 vt = BINFO_VTABLE (binfo);
7054 if (TREE_CODE (vt) == TREE_LIST)
7055 vt = TREE_VALUE (vt);
7056 if (TREE_CODE (vt) == TREE_BINFO)
7065 /* Data for secondary VTT initialization. */
7066 typedef struct secondary_vptr_vtt_init_data_s
7068 /* Is this the primary VTT? */
7071 /* Current index into the VTT. */
7074 /* TREE_LIST of initializers built up. */
7077 /* The type being constructed by this secondary VTT. */
7078 tree type_being_constructed;
7079 } secondary_vptr_vtt_init_data;
7081 /* Recursively build the VTT-initializer for BINFO (which is in the
7082 hierarchy dominated by T). INITS points to the end of the initializer
7083 list to date. INDEX is the VTT index where the next element will be
7084 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7085 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7086 for virtual bases of T. When it is not so, we build the constructor
7087 vtables for the BINFO-in-T variant. */
7090 build_vtt_inits (tree binfo, tree t, tree *inits, tree *index)
7095 tree secondary_vptrs;
7096 secondary_vptr_vtt_init_data data;
7097 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7099 /* We only need VTTs for subobjects with virtual bases. */
7100 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7103 /* We need to use a construction vtable if this is not the primary
7107 build_ctor_vtbl_group (binfo, t);
7109 /* Record the offset in the VTT where this sub-VTT can be found. */
7110 BINFO_SUBVTT_INDEX (binfo) = *index;
7113 /* Add the address of the primary vtable for the complete object. */
7114 init = binfo_ctor_vtable (binfo);
7115 *inits = build_tree_list (NULL_TREE, init);
7116 inits = &TREE_CHAIN (*inits);
7119 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7120 BINFO_VPTR_INDEX (binfo) = *index;
7122 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7124 /* Recursively add the secondary VTTs for non-virtual bases. */
7125 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7126 if (!BINFO_VIRTUAL_P (b))
7127 inits = build_vtt_inits (b, t, inits, index);
7129 /* Add secondary virtual pointers for all subobjects of BINFO with
7130 either virtual bases or reachable along a virtual path, except
7131 subobjects that are non-virtual primary bases. */
7132 data.top_level_p = top_level_p;
7133 data.index = *index;
7135 data.type_being_constructed = BINFO_TYPE (binfo);
7137 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7139 *index = data.index;
7141 /* The secondary vptrs come back in reverse order. After we reverse
7142 them, and add the INITS, the last init will be the first element
7144 secondary_vptrs = data.inits;
7145 if (secondary_vptrs)
7147 *inits = nreverse (secondary_vptrs);
7148 inits = &TREE_CHAIN (secondary_vptrs);
7149 gcc_assert (*inits == NULL_TREE);
7153 /* Add the secondary VTTs for virtual bases in inheritance graph
7155 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7157 if (!BINFO_VIRTUAL_P (b))
7160 inits = build_vtt_inits (b, t, inits, index);
7163 /* Remove the ctor vtables we created. */
7164 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7169 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7170 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7173 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7175 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7177 /* We don't care about bases that don't have vtables. */
7178 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7179 return dfs_skip_bases;
7181 /* We're only interested in proper subobjects of the type being
7183 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7186 /* We're only interested in bases with virtual bases or reachable
7187 via a virtual path from the type being constructed. */
7188 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7189 || binfo_via_virtual (binfo, data->type_being_constructed)))
7190 return dfs_skip_bases;
7192 /* We're not interested in non-virtual primary bases. */
7193 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7196 /* Record the index where this secondary vptr can be found. */
7197 if (data->top_level_p)
7199 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7200 BINFO_VPTR_INDEX (binfo) = data->index;
7202 if (BINFO_VIRTUAL_P (binfo))
7204 /* It's a primary virtual base, and this is not a
7205 construction vtable. Find the base this is primary of in
7206 the inheritance graph, and use that base's vtable
7208 while (BINFO_PRIMARY_P (binfo))
7209 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7213 /* Add the initializer for the secondary vptr itself. */
7214 data->inits = tree_cons (NULL_TREE, binfo_ctor_vtable (binfo), data->inits);
7216 /* Advance the vtt index. */
7217 data->index = size_binop (PLUS_EXPR, data->index,
7218 TYPE_SIZE_UNIT (ptr_type_node));
7223 /* Called from build_vtt_inits via dfs_walk. After building
7224 constructor vtables and generating the sub-vtt from them, we need
7225 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7226 binfo of the base whose sub vtt was generated. */
7229 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7231 tree vtable = BINFO_VTABLE (binfo);
7233 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7234 /* If this class has no vtable, none of its bases do. */
7235 return dfs_skip_bases;
7238 /* This might be a primary base, so have no vtable in this
7242 /* If we scribbled the construction vtable vptr into BINFO, clear it
7244 if (TREE_CODE (vtable) == TREE_LIST
7245 && (TREE_PURPOSE (vtable) == (tree) data))
7246 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7251 /* Build the construction vtable group for BINFO which is in the
7252 hierarchy dominated by T. */
7255 build_ctor_vtbl_group (tree binfo, tree t)
7264 /* See if we've already created this construction vtable group. */
7265 id = mangle_ctor_vtbl_for_type (t, binfo);
7266 if (IDENTIFIER_GLOBAL_VALUE (id))
7269 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7270 /* Build a version of VTBL (with the wrong type) for use in
7271 constructing the addresses of secondary vtables in the
7272 construction vtable group. */
7273 vtbl = build_vtable (t, id, ptr_type_node);
7274 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7275 list = build_tree_list (vtbl, NULL_TREE);
7276 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7279 /* Add the vtables for each of our virtual bases using the vbase in T
7281 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7283 vbase = TREE_CHAIN (vbase))
7287 if (!BINFO_VIRTUAL_P (vbase))
7289 b = copied_binfo (vbase, binfo);
7291 accumulate_vtbl_inits (b, vbase, binfo, t, list);
7293 inits = TREE_VALUE (list);
7295 /* Figure out the type of the construction vtable. */
7296 type = build_index_type (size_int (list_length (inits) - 1));
7297 type = build_cplus_array_type (vtable_entry_type, type);
7299 TREE_TYPE (vtbl) = type;
7300 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7301 layout_decl (vtbl, 0);
7303 /* Initialize the construction vtable. */
7304 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7305 initialize_artificial_var (vtbl, inits);
7306 dump_vtable (t, binfo, vtbl);
7309 /* Add the vtbl initializers for BINFO (and its bases other than
7310 non-virtual primaries) to the list of INITS. BINFO is in the
7311 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7312 the constructor the vtbl inits should be accumulated for. (If this
7313 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7314 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7315 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7316 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7317 but are not necessarily the same in terms of layout. */
7320 accumulate_vtbl_inits (tree binfo,
7328 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7330 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7332 /* If it doesn't have a vptr, we don't do anything. */
7333 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7336 /* If we're building a construction vtable, we're not interested in
7337 subobjects that don't require construction vtables. */
7339 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7340 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7343 /* Build the initializers for the BINFO-in-T vtable. */
7345 = chainon (TREE_VALUE (inits),
7346 dfs_accumulate_vtbl_inits (binfo, orig_binfo,
7347 rtti_binfo, t, inits));
7349 /* Walk the BINFO and its bases. We walk in preorder so that as we
7350 initialize each vtable we can figure out at what offset the
7351 secondary vtable lies from the primary vtable. We can't use
7352 dfs_walk here because we need to iterate through bases of BINFO
7353 and RTTI_BINFO simultaneously. */
7354 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7356 /* Skip virtual bases. */
7357 if (BINFO_VIRTUAL_P (base_binfo))
7359 accumulate_vtbl_inits (base_binfo,
7360 BINFO_BASE_BINFO (orig_binfo, i),
7366 /* Called from accumulate_vtbl_inits. Returns the initializers for
7367 the BINFO vtable. */
7370 dfs_accumulate_vtbl_inits (tree binfo,
7376 tree inits = NULL_TREE;
7377 tree vtbl = NULL_TREE;
7378 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7381 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7383 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7384 primary virtual base. If it is not the same primary in
7385 the hierarchy of T, we'll need to generate a ctor vtable
7386 for it, to place at its location in T. If it is the same
7387 primary, we still need a VTT entry for the vtable, but it
7388 should point to the ctor vtable for the base it is a
7389 primary for within the sub-hierarchy of RTTI_BINFO.
7391 There are three possible cases:
7393 1) We are in the same place.
7394 2) We are a primary base within a lost primary virtual base of
7396 3) We are primary to something not a base of RTTI_BINFO. */
7399 tree last = NULL_TREE;
7401 /* First, look through the bases we are primary to for RTTI_BINFO
7402 or a virtual base. */
7404 while (BINFO_PRIMARY_P (b))
7406 b = BINFO_INHERITANCE_CHAIN (b);
7408 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7411 /* If we run out of primary links, keep looking down our
7412 inheritance chain; we might be an indirect primary. */
7413 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7414 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7418 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7419 base B and it is a base of RTTI_BINFO, this is case 2. In
7420 either case, we share our vtable with LAST, i.e. the
7421 derived-most base within B of which we are a primary. */
7423 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7424 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7425 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7426 binfo_ctor_vtable after everything's been set up. */
7429 /* Otherwise, this is case 3 and we get our own. */
7431 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7439 /* Compute the initializer for this vtable. */
7440 inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7443 /* Figure out the position to which the VPTR should point. */
7444 vtbl = TREE_PURPOSE (l);
7445 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7446 index = size_binop (PLUS_EXPR,
7447 size_int (non_fn_entries),
7448 size_int (list_length (TREE_VALUE (l))));
7449 index = size_binop (MULT_EXPR,
7450 TYPE_SIZE_UNIT (vtable_entry_type),
7452 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7456 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7457 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7458 straighten this out. */
7459 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7460 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7463 /* For an ordinary vtable, set BINFO_VTABLE. */
7464 BINFO_VTABLE (binfo) = vtbl;
7469 static GTY(()) tree abort_fndecl_addr;
7471 /* Construct the initializer for BINFO's virtual function table. BINFO
7472 is part of the hierarchy dominated by T. If we're building a
7473 construction vtable, the ORIG_BINFO is the binfo we should use to
7474 find the actual function pointers to put in the vtable - but they
7475 can be overridden on the path to most-derived in the graph that
7476 ORIG_BINFO belongs. Otherwise,
7477 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7478 BINFO that should be indicated by the RTTI information in the
7479 vtable; it will be a base class of T, rather than T itself, if we
7480 are building a construction vtable.
7482 The value returned is a TREE_LIST suitable for wrapping in a
7483 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7484 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7485 number of non-function entries in the vtable.
7487 It might seem that this function should never be called with a
7488 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7489 base is always subsumed by a derived class vtable. However, when
7490 we are building construction vtables, we do build vtables for
7491 primary bases; we need these while the primary base is being
7495 build_vtbl_initializer (tree binfo,
7499 int* non_fn_entries_p)
7506 VEC(tree,gc) *vbases;
7508 /* Initialize VID. */
7509 memset (&vid, 0, sizeof (vid));
7512 vid.rtti_binfo = rtti_binfo;
7513 vid.last_init = &vid.inits;
7514 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7515 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7516 vid.generate_vcall_entries = true;
7517 /* The first vbase or vcall offset is at index -3 in the vtable. */
7518 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7520 /* Add entries to the vtable for RTTI. */
7521 build_rtti_vtbl_entries (binfo, &vid);
7523 /* Create an array for keeping track of the functions we've
7524 processed. When we see multiple functions with the same
7525 signature, we share the vcall offsets. */
7526 vid.fns = VEC_alloc (tree, gc, 32);
7527 /* Add the vcall and vbase offset entries. */
7528 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7530 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7531 build_vbase_offset_vtbl_entries. */
7532 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7533 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7534 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7536 /* If the target requires padding between data entries, add that now. */
7537 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7541 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7546 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7547 add = tree_cons (NULL_TREE,
7548 build1 (NOP_EXPR, vtable_entry_type,
7555 if (non_fn_entries_p)
7556 *non_fn_entries_p = list_length (vid.inits);
7558 /* Go through all the ordinary virtual functions, building up
7560 vfun_inits = NULL_TREE;
7561 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7565 tree fn, fn_original;
7566 tree init = NULL_TREE;
7570 if (DECL_THUNK_P (fn))
7572 if (!DECL_NAME (fn))
7574 if (THUNK_ALIAS (fn))
7576 fn = THUNK_ALIAS (fn);
7579 fn_original = THUNK_TARGET (fn);
7582 /* If the only definition of this function signature along our
7583 primary base chain is from a lost primary, this vtable slot will
7584 never be used, so just zero it out. This is important to avoid
7585 requiring extra thunks which cannot be generated with the function.
7587 We first check this in update_vtable_entry_for_fn, so we handle
7588 restored primary bases properly; we also need to do it here so we
7589 zero out unused slots in ctor vtables, rather than filling them
7590 with erroneous values (though harmless, apart from relocation
7592 for (b = binfo; ; b = get_primary_binfo (b))
7594 /* We found a defn before a lost primary; go ahead as normal. */
7595 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7598 /* The nearest definition is from a lost primary; clear the
7600 if (BINFO_LOST_PRIMARY_P (b))
7602 init = size_zero_node;
7609 /* Pull the offset for `this', and the function to call, out of
7611 delta = BV_DELTA (v);
7612 vcall_index = BV_VCALL_INDEX (v);
7614 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7615 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7617 /* You can't call an abstract virtual function; it's abstract.
7618 So, we replace these functions with __pure_virtual. */
7619 if (DECL_PURE_VIRTUAL_P (fn_original))
7622 if (abort_fndecl_addr == NULL)
7623 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7624 init = abort_fndecl_addr;
7628 if (!integer_zerop (delta) || vcall_index)
7630 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7631 if (!DECL_NAME (fn))
7634 /* Take the address of the function, considering it to be of an
7635 appropriate generic type. */
7636 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7640 /* And add it to the chain of initializers. */
7641 if (TARGET_VTABLE_USES_DESCRIPTORS)
7644 if (init == size_zero_node)
7645 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7646 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7648 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7650 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7651 TREE_OPERAND (init, 0),
7652 build_int_cst (NULL_TREE, i));
7653 TREE_CONSTANT (fdesc) = 1;
7655 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7659 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7662 /* The initializers for virtual functions were built up in reverse
7663 order; straighten them out now. */
7664 vfun_inits = nreverse (vfun_inits);
7666 /* The negative offset initializers are also in reverse order. */
7667 vid.inits = nreverse (vid.inits);
7669 /* Chain the two together. */
7670 return chainon (vid.inits, vfun_inits);
7673 /* Adds to vid->inits the initializers for the vbase and vcall
7674 offsets in BINFO, which is in the hierarchy dominated by T. */
7677 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7681 /* If this is a derived class, we must first create entries
7682 corresponding to the primary base class. */
7683 b = get_primary_binfo (binfo);
7685 build_vcall_and_vbase_vtbl_entries (b, vid);
7687 /* Add the vbase entries for this base. */
7688 build_vbase_offset_vtbl_entries (binfo, vid);
7689 /* Add the vcall entries for this base. */
7690 build_vcall_offset_vtbl_entries (binfo, vid);
7693 /* Returns the initializers for the vbase offset entries in the vtable
7694 for BINFO (which is part of the class hierarchy dominated by T), in
7695 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7696 where the next vbase offset will go. */
7699 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7703 tree non_primary_binfo;
7705 /* If there are no virtual baseclasses, then there is nothing to
7707 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7712 /* We might be a primary base class. Go up the inheritance hierarchy
7713 until we find the most derived class of which we are a primary base:
7714 it is the offset of that which we need to use. */
7715 non_primary_binfo = binfo;
7716 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7720 /* If we have reached a virtual base, then it must be a primary
7721 base (possibly multi-level) of vid->binfo, or we wouldn't
7722 have called build_vcall_and_vbase_vtbl_entries for it. But it
7723 might be a lost primary, so just skip down to vid->binfo. */
7724 if (BINFO_VIRTUAL_P (non_primary_binfo))
7726 non_primary_binfo = vid->binfo;
7730 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7731 if (get_primary_binfo (b) != non_primary_binfo)
7733 non_primary_binfo = b;
7736 /* Go through the virtual bases, adding the offsets. */
7737 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7739 vbase = TREE_CHAIN (vbase))
7744 if (!BINFO_VIRTUAL_P (vbase))
7747 /* Find the instance of this virtual base in the complete
7749 b = copied_binfo (vbase, binfo);
7751 /* If we've already got an offset for this virtual base, we
7752 don't need another one. */
7753 if (BINFO_VTABLE_PATH_MARKED (b))
7755 BINFO_VTABLE_PATH_MARKED (b) = 1;
7757 /* Figure out where we can find this vbase offset. */
7758 delta = size_binop (MULT_EXPR,
7761 TYPE_SIZE_UNIT (vtable_entry_type)));
7762 if (vid->primary_vtbl_p)
7763 BINFO_VPTR_FIELD (b) = delta;
7765 if (binfo != TYPE_BINFO (t))
7766 /* The vbase offset had better be the same. */
7767 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7769 /* The next vbase will come at a more negative offset. */
7770 vid->index = size_binop (MINUS_EXPR, vid->index,
7771 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7773 /* The initializer is the delta from BINFO to this virtual base.
7774 The vbase offsets go in reverse inheritance-graph order, and
7775 we are walking in inheritance graph order so these end up in
7777 delta = size_diffop_loc (input_location,
7778 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7781 = build_tree_list (NULL_TREE,
7782 fold_build1_loc (input_location, NOP_EXPR,
7785 vid->last_init = &TREE_CHAIN (*vid->last_init);
7789 /* Adds the initializers for the vcall offset entries in the vtable
7790 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7794 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7796 /* We only need these entries if this base is a virtual base. We
7797 compute the indices -- but do not add to the vtable -- when
7798 building the main vtable for a class. */
7799 if (binfo == TYPE_BINFO (vid->derived)
7800 || (BINFO_VIRTUAL_P (binfo)
7801 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7802 correspond to VID->DERIVED), we are building a primary
7803 construction virtual table. Since this is a primary
7804 virtual table, we do not need the vcall offsets for
7806 && binfo != vid->rtti_binfo))
7808 /* We need a vcall offset for each of the virtual functions in this
7809 vtable. For example:
7811 class A { virtual void f (); };
7812 class B1 : virtual public A { virtual void f (); };
7813 class B2 : virtual public A { virtual void f (); };
7814 class C: public B1, public B2 { virtual void f (); };
7816 A C object has a primary base of B1, which has a primary base of A. A
7817 C also has a secondary base of B2, which no longer has a primary base
7818 of A. So the B2-in-C construction vtable needs a secondary vtable for
7819 A, which will adjust the A* to a B2* to call f. We have no way of
7820 knowing what (or even whether) this offset will be when we define B2,
7821 so we store this "vcall offset" in the A sub-vtable and look it up in
7822 a "virtual thunk" for B2::f.
7824 We need entries for all the functions in our primary vtable and
7825 in our non-virtual bases' secondary vtables. */
7827 /* If we are just computing the vcall indices -- but do not need
7828 the actual entries -- not that. */
7829 if (!BINFO_VIRTUAL_P (binfo))
7830 vid->generate_vcall_entries = false;
7831 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7832 add_vcall_offset_vtbl_entries_r (binfo, vid);
7836 /* Build vcall offsets, starting with those for BINFO. */
7839 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7845 /* Don't walk into virtual bases -- except, of course, for the
7846 virtual base for which we are building vcall offsets. Any
7847 primary virtual base will have already had its offsets generated
7848 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7849 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7852 /* If BINFO has a primary base, process it first. */
7853 primary_binfo = get_primary_binfo (binfo);
7855 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7857 /* Add BINFO itself to the list. */
7858 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7860 /* Scan the non-primary bases of BINFO. */
7861 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7862 if (base_binfo != primary_binfo)
7863 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7866 /* Called from build_vcall_offset_vtbl_entries_r. */
7869 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7871 /* Make entries for the rest of the virtuals. */
7872 if (abi_version_at_least (2))
7876 /* The ABI requires that the methods be processed in declaration
7877 order. G++ 3.2 used the order in the vtable. */
7878 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7880 orig_fn = TREE_CHAIN (orig_fn))
7881 if (DECL_VINDEX (orig_fn))
7882 add_vcall_offset (orig_fn, binfo, vid);
7886 tree derived_virtuals;
7889 /* If BINFO is a primary base, the most derived class which has
7890 BINFO as a primary base; otherwise, just BINFO. */
7891 tree non_primary_binfo;
7893 /* We might be a primary base class. Go up the inheritance hierarchy
7894 until we find the most derived class of which we are a primary base:
7895 it is the BINFO_VIRTUALS there that we need to consider. */
7896 non_primary_binfo = binfo;
7897 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7901 /* If we have reached a virtual base, then it must be vid->vbase,
7902 because we ignore other virtual bases in
7903 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7904 base (possibly multi-level) of vid->binfo, or we wouldn't
7905 have called build_vcall_and_vbase_vtbl_entries for it. But it
7906 might be a lost primary, so just skip down to vid->binfo. */
7907 if (BINFO_VIRTUAL_P (non_primary_binfo))
7909 gcc_assert (non_primary_binfo == vid->vbase);
7910 non_primary_binfo = vid->binfo;
7914 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7915 if (get_primary_binfo (b) != non_primary_binfo)
7917 non_primary_binfo = b;
7920 if (vid->ctor_vtbl_p)
7921 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7922 where rtti_binfo is the most derived type. */
7924 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7926 for (base_virtuals = BINFO_VIRTUALS (binfo),
7927 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7928 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7930 base_virtuals = TREE_CHAIN (base_virtuals),
7931 derived_virtuals = TREE_CHAIN (derived_virtuals),
7932 orig_virtuals = TREE_CHAIN (orig_virtuals))
7936 /* Find the declaration that originally caused this function to
7937 be present in BINFO_TYPE (binfo). */
7938 orig_fn = BV_FN (orig_virtuals);
7940 /* When processing BINFO, we only want to generate vcall slots for
7941 function slots introduced in BINFO. So don't try to generate
7942 one if the function isn't even defined in BINFO. */
7943 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7946 add_vcall_offset (orig_fn, binfo, vid);
7951 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7954 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7960 /* If there is already an entry for a function with the same
7961 signature as FN, then we do not need a second vcall offset.
7962 Check the list of functions already present in the derived
7964 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7966 if (same_signature_p (derived_entry, orig_fn)
7967 /* We only use one vcall offset for virtual destructors,
7968 even though there are two virtual table entries. */
7969 || (DECL_DESTRUCTOR_P (derived_entry)
7970 && DECL_DESTRUCTOR_P (orig_fn)))
7974 /* If we are building these vcall offsets as part of building
7975 the vtable for the most derived class, remember the vcall
7977 if (vid->binfo == TYPE_BINFO (vid->derived))
7979 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
7980 CLASSTYPE_VCALL_INDICES (vid->derived),
7982 elt->purpose = orig_fn;
7983 elt->value = vid->index;
7986 /* The next vcall offset will be found at a more negative
7988 vid->index = size_binop (MINUS_EXPR, vid->index,
7989 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7991 /* Keep track of this function. */
7992 VEC_safe_push (tree, gc, vid->fns, orig_fn);
7994 if (vid->generate_vcall_entries)
7999 /* Find the overriding function. */
8000 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8001 if (fn == error_mark_node)
8002 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
8006 base = TREE_VALUE (fn);
8008 /* The vbase we're working on is a primary base of
8009 vid->binfo. But it might be a lost primary, so its
8010 BINFO_OFFSET might be wrong, so we just use the
8011 BINFO_OFFSET from vid->binfo. */
8012 vcall_offset = size_diffop_loc (input_location,
8013 BINFO_OFFSET (base),
8014 BINFO_OFFSET (vid->binfo));
8015 vcall_offset = fold_build1_loc (input_location,
8016 NOP_EXPR, vtable_entry_type,
8019 /* Add the initializer to the vtable. */
8020 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
8021 vid->last_init = &TREE_CHAIN (*vid->last_init);
8025 /* Return vtbl initializers for the RTTI entries corresponding to the
8026 BINFO's vtable. The RTTI entries should indicate the object given
8027 by VID->rtti_binfo. */
8030 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8039 basetype = BINFO_TYPE (binfo);
8040 t = BINFO_TYPE (vid->rtti_binfo);
8042 /* To find the complete object, we will first convert to our most
8043 primary base, and then add the offset in the vtbl to that value. */
8045 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8046 && !BINFO_LOST_PRIMARY_P (b))
8050 primary_base = get_primary_binfo (b);
8051 gcc_assert (BINFO_PRIMARY_P (primary_base)
8052 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8055 offset = size_diffop_loc (input_location,
8056 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8058 /* The second entry is the address of the typeinfo object. */
8060 decl = build_address (get_tinfo_decl (t));
8062 decl = integer_zero_node;
8064 /* Convert the declaration to a type that can be stored in the
8066 init = build_nop (vfunc_ptr_type_node, decl);
8067 *vid->last_init = build_tree_list (NULL_TREE, init);
8068 vid->last_init = &TREE_CHAIN (*vid->last_init);
8070 /* Add the offset-to-top entry. It comes earlier in the vtable than
8071 the typeinfo entry. Convert the offset to look like a
8072 function pointer, so that we can put it in the vtable. */
8073 init = build_nop (vfunc_ptr_type_node, offset);
8074 *vid->last_init = build_tree_list (NULL_TREE, init);
8075 vid->last_init = &TREE_CHAIN (*vid->last_init);
8078 /* Fold a OBJ_TYPE_REF expression to the address of a function.
8079 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
8082 cp_fold_obj_type_ref (tree ref, tree known_type)
8084 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
8085 HOST_WIDE_INT i = 0;
8086 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
8091 i += (TARGET_VTABLE_USES_DESCRIPTORS
8092 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
8098 #ifdef ENABLE_CHECKING
8099 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
8100 DECL_VINDEX (fndecl)));
8103 cgraph_node (fndecl)->local.vtable_method = true;
8105 return build_address (fndecl);
8108 #include "gt-cp-class.h"