1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
38 #include "tree-dump.h"
39 #include "splay-tree.h"
40 #include "pointer-set.h"
42 /* The number of nested classes being processed. If we are not in the
43 scope of any class, this is zero. */
45 int current_class_depth;
47 /* In order to deal with nested classes, we keep a stack of classes.
48 The topmost entry is the innermost class, and is the entry at index
49 CURRENT_CLASS_DEPTH */
51 typedef struct class_stack_node {
52 /* The name of the class. */
55 /* The _TYPE node for the class. */
58 /* The access specifier pending for new declarations in the scope of
62 /* If were defining TYPE, the names used in this class. */
63 splay_tree names_used;
65 /* Nonzero if this class is no longer open, because of a call to
68 }* class_stack_node_t;
70 typedef struct vtbl_init_data_s
72 /* The base for which we're building initializers. */
74 /* The type of the most-derived type. */
76 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
77 unless ctor_vtbl_p is true. */
79 /* The negative-index vtable initializers built up so far. These
80 are in order from least negative index to most negative index. */
81 VEC(constructor_elt,gc) *inits;
82 /* The binfo for the virtual base for which we're building
83 vcall offset initializers. */
85 /* The functions in vbase for which we have already provided vcall
88 /* The vtable index of the next vcall or vbase offset. */
90 /* Nonzero if we are building the initializer for the primary
93 /* Nonzero if we are building the initializer for a construction
96 /* True when adding vcall offset entries to the vtable. False when
97 merely computing the indices. */
98 bool generate_vcall_entries;
101 /* The type of a function passed to walk_subobject_offsets. */
102 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
104 /* The stack itself. This is a dynamically resized array. The
105 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
106 static int current_class_stack_size;
107 static class_stack_node_t current_class_stack;
109 /* The size of the largest empty class seen in this translation unit. */
110 static GTY (()) tree sizeof_biggest_empty_class;
112 /* An array of all local classes present in this translation unit, in
113 declaration order. */
114 VEC(tree,gc) *local_classes;
116 static tree get_vfield_name (tree);
117 static void finish_struct_anon (tree);
118 static tree get_vtable_name (tree);
119 static tree get_basefndecls (tree, tree);
120 static int build_primary_vtable (tree, tree);
121 static int build_secondary_vtable (tree);
122 static void finish_vtbls (tree);
123 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
124 static void finish_struct_bits (tree);
125 static int alter_access (tree, tree, tree);
126 static void handle_using_decl (tree, tree);
127 static tree dfs_modify_vtables (tree, void *);
128 static tree modify_all_vtables (tree, tree);
129 static void determine_primary_bases (tree);
130 static void finish_struct_methods (tree);
131 static void maybe_warn_about_overly_private_class (tree);
132 static int method_name_cmp (const void *, const void *);
133 static int resort_method_name_cmp (const void *, const void *);
134 static void add_implicitly_declared_members (tree, int, int);
135 static tree fixed_type_or_null (tree, int *, int *);
136 static tree build_simple_base_path (tree expr, tree binfo);
137 static tree build_vtbl_ref_1 (tree, tree);
138 static void build_vtbl_initializer (tree, tree, tree, tree, int *,
139 VEC(constructor_elt,gc) **);
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, VEC(constructor_elt,gc) *);
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 VEC(constructor_elt,gc) **);
183 static void dfs_accumulate_vtbl_inits (tree, tree, tree, tree, tree,
184 VEC(constructor_elt,gc) **);
185 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
186 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
187 static void clone_constructors_and_destructors (tree);
188 static tree build_clone (tree, tree);
189 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
190 static void build_ctor_vtbl_group (tree, tree);
191 static void build_vtt (tree);
192 static tree binfo_ctor_vtable (tree);
193 static void build_vtt_inits (tree, tree, VEC(constructor_elt,gc) **, tree *);
194 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
195 static tree dfs_fixup_binfo_vtbls (tree, void *);
196 static int record_subobject_offset (tree, tree, splay_tree);
197 static int check_subobject_offset (tree, tree, splay_tree);
198 static int walk_subobject_offsets (tree, subobject_offset_fn,
199 tree, splay_tree, tree, int);
200 static void record_subobject_offsets (tree, tree, splay_tree, bool);
201 static int layout_conflict_p (tree, tree, splay_tree, int);
202 static int splay_tree_compare_integer_csts (splay_tree_key k1,
204 static void warn_about_ambiguous_bases (tree);
205 static bool type_requires_array_cookie (tree);
206 static bool contains_empty_class_p (tree);
207 static bool base_derived_from (tree, tree);
208 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
209 static tree end_of_base (tree);
210 static tree get_vcall_index (tree, tree);
212 /* Variables shared between class.c and call.c. */
214 #ifdef GATHER_STATISTICS
216 int n_vtable_entries = 0;
217 int n_vtable_searches = 0;
218 int n_vtable_elems = 0;
219 int n_convert_harshness = 0;
220 int n_compute_conversion_costs = 0;
221 int n_inner_fields_searched = 0;
224 /* Convert to or from a base subobject. EXPR is an expression of type
225 `A' or `A*', an expression of type `B' or `B*' is returned. To
226 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
227 the B base instance within A. To convert base A to derived B, CODE
228 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
229 In this latter case, A must not be a morally virtual base of B.
230 NONNULL is true if EXPR is known to be non-NULL (this is only
231 needed when EXPR is of pointer type). CV qualifiers are preserved
235 build_base_path (enum tree_code code,
239 tsubst_flags_t complain)
241 tree v_binfo = NULL_TREE;
242 tree d_binfo = NULL_TREE;
246 tree null_test = NULL;
247 tree ptr_target_type;
249 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
250 bool has_empty = false;
253 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
254 return error_mark_node;
256 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
259 if (is_empty_class (BINFO_TYPE (probe)))
261 if (!v_binfo && BINFO_VIRTUAL_P (probe))
265 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
267 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
269 if (code == PLUS_EXPR
270 && !SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe))
272 /* This can happen when adjust_result_of_qualified_name_lookup can't
273 find a unique base binfo in a call to a member function. We
274 couldn't give the diagnostic then since we might have been calling
275 a static member function, so we do it now. */
276 if (complain & tf_error)
278 tree base = lookup_base (probe, BINFO_TYPE (d_binfo),
280 gcc_assert (base == error_mark_node);
282 return error_mark_node;
285 gcc_assert ((code == MINUS_EXPR
286 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
287 || code == PLUS_EXPR);
289 if (binfo == d_binfo)
293 if (code == MINUS_EXPR && v_binfo)
295 if (complain & tf_error)
296 error ("cannot convert from base %qT to derived type %qT via "
297 "virtual base %qT", BINFO_TYPE (binfo), BINFO_TYPE (d_binfo),
298 BINFO_TYPE (v_binfo));
299 return error_mark_node;
303 /* This must happen before the call to save_expr. */
304 expr = cp_build_addr_expr (expr, complain);
306 expr = mark_rvalue_use (expr);
308 offset = BINFO_OFFSET (binfo);
309 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
310 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
311 /* TARGET_TYPE has been extracted from BINFO, and, is therefore always
312 cv-unqualified. Extract the cv-qualifiers from EXPR so that the
313 expression returned matches the input. */
314 target_type = cp_build_qualified_type
315 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
316 ptr_target_type = build_pointer_type (target_type);
318 /* Do we need to look in the vtable for the real offset? */
319 virtual_access = (v_binfo && fixed_type_p <= 0);
321 /* Don't bother with the calculations inside sizeof; they'll ICE if the
322 source type is incomplete and the pointer value doesn't matter. In a
323 template (even in fold_non_dependent_expr), we don't have vtables set
324 up properly yet, and the value doesn't matter there either; we're just
325 interested in the result of overload resolution. */
326 if (cp_unevaluated_operand != 0
327 || (current_function_decl
328 && uses_template_parms (current_function_decl)))
330 expr = build_nop (ptr_target_type, expr);
332 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
336 /* If we're in an NSDMI, we don't have the full constructor context yet
337 that we need for converting to a virtual base, so just build a stub
338 CONVERT_EXPR and expand it later in bot_replace. */
339 if (virtual_access && fixed_type_p < 0
340 && current_scope () != current_function_decl)
342 expr = build1 (CONVERT_EXPR, ptr_target_type, expr);
343 CONVERT_EXPR_VBASE_PATH (expr) = true;
345 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
349 /* Do we need to check for a null pointer? */
350 if (want_pointer && !nonnull)
352 /* If we know the conversion will not actually change the value
353 of EXPR, then we can avoid testing the expression for NULL.
354 We have to avoid generating a COMPONENT_REF for a base class
355 field, because other parts of the compiler know that such
356 expressions are always non-NULL. */
357 if (!virtual_access && integer_zerop (offset))
358 return build_nop (ptr_target_type, expr);
359 null_test = error_mark_node;
362 /* Protect against multiple evaluation if necessary. */
363 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
364 expr = save_expr (expr);
366 /* Now that we've saved expr, build the real null test. */
369 tree zero = cp_convert (TREE_TYPE (expr), nullptr_node);
370 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
374 /* If this is a simple base reference, express it as a COMPONENT_REF. */
375 if (code == PLUS_EXPR && !virtual_access
376 /* We don't build base fields for empty bases, and they aren't very
377 interesting to the optimizers anyway. */
380 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
381 expr = build_simple_base_path (expr, binfo);
383 expr = build_address (expr);
384 target_type = TREE_TYPE (expr);
390 /* Going via virtual base V_BINFO. We need the static offset
391 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
392 V_BINFO. That offset is an entry in D_BINFO's vtable. */
395 if (fixed_type_p < 0 && in_base_initializer)
397 /* In a base member initializer, we cannot rely on the
398 vtable being set up. We have to indirect via the
402 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
403 t = build_pointer_type (t);
404 v_offset = convert (t, current_vtt_parm);
405 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
408 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, RO_NULL,
410 TREE_TYPE (TREE_TYPE (expr)));
412 v_offset = fold_build_pointer_plus (v_offset, BINFO_VPTR_FIELD (v_binfo));
413 v_offset = build1 (NOP_EXPR,
414 build_pointer_type (ptrdiff_type_node),
416 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
417 TREE_CONSTANT (v_offset) = 1;
419 offset = convert_to_integer (ptrdiff_type_node,
420 size_diffop_loc (input_location, offset,
421 BINFO_OFFSET (v_binfo)));
423 if (!integer_zerop (offset))
424 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
426 if (fixed_type_p < 0)
427 /* Negative fixed_type_p means this is a constructor or destructor;
428 virtual base layout is fixed in in-charge [cd]tors, but not in
430 offset = build3 (COND_EXPR, ptrdiff_type_node,
431 build2 (EQ_EXPR, boolean_type_node,
432 current_in_charge_parm, integer_zero_node),
434 convert_to_integer (ptrdiff_type_node,
435 BINFO_OFFSET (binfo)));
441 target_type = ptr_target_type;
443 expr = build1 (NOP_EXPR, ptr_target_type, expr);
445 if (!integer_zerop (offset))
447 offset = fold_convert (sizetype, offset);
448 if (code == MINUS_EXPR)
449 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
450 expr = fold_build_pointer_plus (expr, offset);
456 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
460 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
461 build_zero_cst (target_type));
466 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
467 Perform a derived-to-base conversion by recursively building up a
468 sequence of COMPONENT_REFs to the appropriate base fields. */
471 build_simple_base_path (tree expr, tree binfo)
473 tree type = BINFO_TYPE (binfo);
474 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
477 if (d_binfo == NULL_TREE)
481 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
483 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
484 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
485 an lvalue in the front end; only _DECLs and _REFs are lvalues
487 temp = unary_complex_lvalue (ADDR_EXPR, expr);
489 expr = cp_build_indirect_ref (temp, RO_NULL, tf_warning_or_error);
495 expr = build_simple_base_path (expr, d_binfo);
497 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
498 field; field = DECL_CHAIN (field))
499 /* Is this the base field created by build_base_field? */
500 if (TREE_CODE (field) == FIELD_DECL
501 && DECL_FIELD_IS_BASE (field)
502 && TREE_TYPE (field) == type
503 /* If we're looking for a field in the most-derived class,
504 also check the field offset; we can have two base fields
505 of the same type if one is an indirect virtual base and one
506 is a direct non-virtual base. */
507 && (BINFO_INHERITANCE_CHAIN (d_binfo)
508 || tree_int_cst_equal (byte_position (field),
509 BINFO_OFFSET (binfo))))
511 /* We don't use build_class_member_access_expr here, as that
512 has unnecessary checks, and more importantly results in
513 recursive calls to dfs_walk_once. */
514 int type_quals = cp_type_quals (TREE_TYPE (expr));
516 expr = build3 (COMPONENT_REF,
517 cp_build_qualified_type (type, type_quals),
518 expr, field, NULL_TREE);
519 expr = fold_if_not_in_template (expr);
521 /* Mark the expression const or volatile, as appropriate.
522 Even though we've dealt with the type above, we still have
523 to mark the expression itself. */
524 if (type_quals & TYPE_QUAL_CONST)
525 TREE_READONLY (expr) = 1;
526 if (type_quals & TYPE_QUAL_VOLATILE)
527 TREE_THIS_VOLATILE (expr) = 1;
532 /* Didn't find the base field?!? */
536 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
537 type is a class type or a pointer to a class type. In the former
538 case, TYPE is also a class type; in the latter it is another
539 pointer type. If CHECK_ACCESS is true, an error message is emitted
540 if TYPE is inaccessible. If OBJECT has pointer type, the value is
541 assumed to be non-NULL. */
544 convert_to_base (tree object, tree type, bool check_access, bool nonnull,
545 tsubst_flags_t complain)
551 if (TYPE_PTR_P (TREE_TYPE (object)))
553 object_type = TREE_TYPE (TREE_TYPE (object));
554 type = TREE_TYPE (type);
557 object_type = TREE_TYPE (object);
559 access = check_access ? ba_check : ba_unique;
560 if (!(complain & tf_error))
562 binfo = lookup_base (object_type, type,
565 if (!binfo || binfo == error_mark_node)
566 return error_mark_node;
568 return build_base_path (PLUS_EXPR, object, binfo, nonnull, complain);
571 /* EXPR is an expression with unqualified class type. BASE is a base
572 binfo of that class type. Returns EXPR, converted to the BASE
573 type. This function assumes that EXPR is the most derived class;
574 therefore virtual bases can be found at their static offsets. */
577 convert_to_base_statically (tree expr, tree base)
581 expr_type = TREE_TYPE (expr);
582 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
584 /* If this is a non-empty base, use a COMPONENT_REF. */
585 if (!is_empty_class (BINFO_TYPE (base)))
586 return build_simple_base_path (expr, base);
588 /* We use fold_build2 and fold_convert below to simplify the trees
589 provided to the optimizers. It is not safe to call these functions
590 when processing a template because they do not handle C++-specific
592 gcc_assert (!processing_template_decl);
593 expr = cp_build_addr_expr (expr, tf_warning_or_error);
594 if (!integer_zerop (BINFO_OFFSET (base)))
595 expr = fold_build_pointer_plus_loc (input_location,
596 expr, BINFO_OFFSET (base));
597 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
598 expr = build_fold_indirect_ref_loc (input_location, expr);
606 build_vfield_ref (tree datum, tree type)
608 tree vfield, vcontext;
610 if (datum == error_mark_node)
611 return error_mark_node;
613 /* First, convert to the requested type. */
614 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
615 datum = convert_to_base (datum, type, /*check_access=*/false,
616 /*nonnull=*/true, tf_warning_or_error);
618 /* Second, the requested type may not be the owner of its own vptr.
619 If not, convert to the base class that owns it. We cannot use
620 convert_to_base here, because VCONTEXT may appear more than once
621 in the inheritance hierarchy of TYPE, and thus direct conversion
622 between the types may be ambiguous. Following the path back up
623 one step at a time via primary bases avoids the problem. */
624 vfield = TYPE_VFIELD (type);
625 vcontext = DECL_CONTEXT (vfield);
626 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
628 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
629 type = TREE_TYPE (datum);
632 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
635 /* Given an object INSTANCE, return an expression which yields the
636 vtable element corresponding to INDEX. There are many special
637 cases for INSTANCE which we take care of here, mainly to avoid
638 creating extra tree nodes when we don't have to. */
641 build_vtbl_ref_1 (tree instance, tree idx)
644 tree vtbl = NULL_TREE;
646 /* Try to figure out what a reference refers to, and
647 access its virtual function table directly. */
650 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
652 tree basetype = non_reference (TREE_TYPE (instance));
654 if (fixed_type && !cdtorp)
656 tree binfo = lookup_base (fixed_type, basetype,
657 ba_unique | ba_quiet, NULL);
659 vtbl = unshare_expr (BINFO_VTABLE (binfo));
663 vtbl = build_vfield_ref (instance, basetype);
665 aref = build_array_ref (input_location, vtbl, idx);
666 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
672 build_vtbl_ref (tree instance, tree idx)
674 tree aref = build_vtbl_ref_1 (instance, idx);
679 /* Given a stable object pointer INSTANCE_PTR, return an expression which
680 yields a function pointer corresponding to vtable element INDEX. */
683 build_vfn_ref (tree instance_ptr, tree idx)
687 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, RO_NULL,
688 tf_warning_or_error),
691 /* When using function descriptors, the address of the
692 vtable entry is treated as a function pointer. */
693 if (TARGET_VTABLE_USES_DESCRIPTORS)
694 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
695 cp_build_addr_expr (aref, tf_warning_or_error));
697 /* Remember this as a method reference, for later devirtualization. */
698 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
703 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
704 for the given TYPE. */
707 get_vtable_name (tree type)
709 return mangle_vtbl_for_type (type);
712 /* DECL is an entity associated with TYPE, like a virtual table or an
713 implicitly generated constructor. Determine whether or not DECL
714 should have external or internal linkage at the object file
715 level. This routine does not deal with COMDAT linkage and other
716 similar complexities; it simply sets TREE_PUBLIC if it possible for
717 entities in other translation units to contain copies of DECL, in
721 set_linkage_according_to_type (tree type ATTRIBUTE_UNUSED, tree decl)
723 TREE_PUBLIC (decl) = 1;
724 determine_visibility (decl);
727 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
728 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
729 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
732 build_vtable (tree class_type, tree name, tree vtable_type)
736 decl = build_lang_decl (VAR_DECL, name, vtable_type);
737 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
738 now to avoid confusion in mangle_decl. */
739 SET_DECL_ASSEMBLER_NAME (decl, name);
740 DECL_CONTEXT (decl) = class_type;
741 DECL_ARTIFICIAL (decl) = 1;
742 TREE_STATIC (decl) = 1;
743 TREE_READONLY (decl) = 1;
744 DECL_VIRTUAL_P (decl) = 1;
745 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
746 DECL_VTABLE_OR_VTT_P (decl) = 1;
747 /* At one time the vtable info was grabbed 2 words at a time. This
748 fails on sparc unless you have 8-byte alignment. (tiemann) */
749 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
751 set_linkage_according_to_type (class_type, decl);
752 /* The vtable has not been defined -- yet. */
753 DECL_EXTERNAL (decl) = 1;
754 DECL_NOT_REALLY_EXTERN (decl) = 1;
756 /* Mark the VAR_DECL node representing the vtable itself as a
757 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
758 is rather important that such things be ignored because any
759 effort to actually generate DWARF for them will run into
760 trouble when/if we encounter code like:
763 struct S { virtual void member (); };
765 because the artificial declaration of the vtable itself (as
766 manufactured by the g++ front end) will say that the vtable is
767 a static member of `S' but only *after* the debug output for
768 the definition of `S' has already been output. This causes
769 grief because the DWARF entry for the definition of the vtable
770 will try to refer back to an earlier *declaration* of the
771 vtable as a static member of `S' and there won't be one. We
772 might be able to arrange to have the "vtable static member"
773 attached to the member list for `S' before the debug info for
774 `S' get written (which would solve the problem) but that would
775 require more intrusive changes to the g++ front end. */
776 DECL_IGNORED_P (decl) = 1;
781 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
782 or even complete. If this does not exist, create it. If COMPLETE is
783 nonzero, then complete the definition of it -- that will render it
784 impossible to actually build the vtable, but is useful to get at those
785 which are known to exist in the runtime. */
788 get_vtable_decl (tree type, int complete)
792 if (CLASSTYPE_VTABLES (type))
793 return CLASSTYPE_VTABLES (type);
795 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
796 CLASSTYPE_VTABLES (type) = decl;
800 DECL_EXTERNAL (decl) = 1;
801 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
807 /* Build the primary virtual function table for TYPE. If BINFO is
808 non-NULL, build the vtable starting with the initial approximation
809 that it is the same as the one which is the head of the association
810 list. Returns a nonzero value if a new vtable is actually
814 build_primary_vtable (tree binfo, tree type)
819 decl = get_vtable_decl (type, /*complete=*/0);
823 if (BINFO_NEW_VTABLE_MARKED (binfo))
824 /* We have already created a vtable for this base, so there's
825 no need to do it again. */
828 virtuals = copy_list (BINFO_VIRTUALS (binfo));
829 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
830 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
831 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
835 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
836 virtuals = NULL_TREE;
839 #ifdef GATHER_STATISTICS
841 n_vtable_elems += list_length (virtuals);
844 /* Initialize the association list for this type, based
845 on our first approximation. */
846 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
847 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
848 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
852 /* Give BINFO a new virtual function table which is initialized
853 with a skeleton-copy of its original initialization. The only
854 entry that changes is the `delta' entry, so we can really
855 share a lot of structure.
857 FOR_TYPE is the most derived type which caused this table to
860 Returns nonzero if we haven't met BINFO before.
862 The order in which vtables are built (by calling this function) for
863 an object must remain the same, otherwise a binary incompatibility
867 build_secondary_vtable (tree binfo)
869 if (BINFO_NEW_VTABLE_MARKED (binfo))
870 /* We already created a vtable for this base. There's no need to
874 /* Remember that we've created a vtable for this BINFO, so that we
875 don't try to do so again. */
876 SET_BINFO_NEW_VTABLE_MARKED (binfo);
878 /* Make fresh virtual list, so we can smash it later. */
879 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
881 /* Secondary vtables are laid out as part of the same structure as
882 the primary vtable. */
883 BINFO_VTABLE (binfo) = NULL_TREE;
887 /* Create a new vtable for BINFO which is the hierarchy dominated by
888 T. Return nonzero if we actually created a new vtable. */
891 make_new_vtable (tree t, tree binfo)
893 if (binfo == TYPE_BINFO (t))
894 /* In this case, it is *type*'s vtable we are modifying. We start
895 with the approximation that its vtable is that of the
896 immediate base class. */
897 return build_primary_vtable (binfo, t);
899 /* This is our very own copy of `basetype' to play with. Later,
900 we will fill in all the virtual functions that override the
901 virtual functions in these base classes which are not defined
902 by the current type. */
903 return build_secondary_vtable (binfo);
906 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
907 (which is in the hierarchy dominated by T) list FNDECL as its
908 BV_FN. DELTA is the required constant adjustment from the `this'
909 pointer where the vtable entry appears to the `this' required when
910 the function is actually called. */
913 modify_vtable_entry (tree t,
923 if (fndecl != BV_FN (v)
924 || !tree_int_cst_equal (delta, BV_DELTA (v)))
926 /* We need a new vtable for BINFO. */
927 if (make_new_vtable (t, binfo))
929 /* If we really did make a new vtable, we also made a copy
930 of the BINFO_VIRTUALS list. Now, we have to find the
931 corresponding entry in that list. */
932 *virtuals = BINFO_VIRTUALS (binfo);
933 while (BV_FN (*virtuals) != BV_FN (v))
934 *virtuals = TREE_CHAIN (*virtuals);
938 BV_DELTA (v) = delta;
939 BV_VCALL_INDEX (v) = NULL_TREE;
945 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
946 the USING_DECL naming METHOD. Returns true if the method could be
947 added to the method vec. */
950 add_method (tree type, tree method, tree using_decl)
954 bool template_conv_p = false;
956 VEC(tree,gc) *method_vec;
958 bool insert_p = false;
962 if (method == error_mark_node)
965 complete_p = COMPLETE_TYPE_P (type);
966 conv_p = DECL_CONV_FN_P (method);
968 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
969 && DECL_TEMPLATE_CONV_FN_P (method));
971 method_vec = CLASSTYPE_METHOD_VEC (type);
974 /* Make a new method vector. We start with 8 entries. We must
975 allocate at least two (for constructors and destructors), and
976 we're going to end up with an assignment operator at some
978 method_vec = VEC_alloc (tree, gc, 8);
979 /* Create slots for constructors and destructors. */
980 VEC_quick_push (tree, method_vec, NULL_TREE);
981 VEC_quick_push (tree, method_vec, NULL_TREE);
982 CLASSTYPE_METHOD_VEC (type) = method_vec;
985 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
986 grok_special_member_properties (method);
988 /* Constructors and destructors go in special slots. */
989 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
990 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
991 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
993 slot = CLASSTYPE_DESTRUCTOR_SLOT;
995 if (TYPE_FOR_JAVA (type))
997 if (!DECL_ARTIFICIAL (method))
998 error ("Java class %qT cannot have a destructor", type);
999 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
1000 error ("Java class %qT cannot have an implicit non-trivial "
1010 /* See if we already have an entry with this name. */
1011 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1012 VEC_iterate (tree, method_vec, slot, m);
1015 m = OVL_CURRENT (m);
1016 if (template_conv_p)
1018 if (TREE_CODE (m) == TEMPLATE_DECL
1019 && DECL_TEMPLATE_CONV_FN_P (m))
1023 if (conv_p && !DECL_CONV_FN_P (m))
1025 if (DECL_NAME (m) == DECL_NAME (method))
1031 && !DECL_CONV_FN_P (m)
1032 && DECL_NAME (m) > DECL_NAME (method))
1036 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1038 /* Check to see if we've already got this method. */
1039 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1041 tree fn = OVL_CURRENT (fns);
1047 if (TREE_CODE (fn) != TREE_CODE (method))
1050 /* [over.load] Member function declarations with the
1051 same name and the same parameter types cannot be
1052 overloaded if any of them is a static member
1053 function declaration.
1055 [namespace.udecl] When a using-declaration brings names
1056 from a base class into a derived class scope, member
1057 functions in the derived class override and/or hide member
1058 functions with the same name and parameter types in a base
1059 class (rather than conflicting). */
1060 fn_type = TREE_TYPE (fn);
1061 method_type = TREE_TYPE (method);
1062 parms1 = TYPE_ARG_TYPES (fn_type);
1063 parms2 = TYPE_ARG_TYPES (method_type);
1065 /* Compare the quals on the 'this' parm. Don't compare
1066 the whole types, as used functions are treated as
1067 coming from the using class in overload resolution. */
1068 if (! DECL_STATIC_FUNCTION_P (fn)
1069 && ! DECL_STATIC_FUNCTION_P (method)
1070 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1071 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1072 && (cp_type_quals (TREE_TYPE (TREE_VALUE (parms1)))
1073 != cp_type_quals (TREE_TYPE (TREE_VALUE (parms2)))))
1076 /* For templates, the return type and template parameters
1077 must be identical. */
1078 if (TREE_CODE (fn) == TEMPLATE_DECL
1079 && (!same_type_p (TREE_TYPE (fn_type),
1080 TREE_TYPE (method_type))
1081 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1082 DECL_TEMPLATE_PARMS (method))))
1085 if (! DECL_STATIC_FUNCTION_P (fn))
1086 parms1 = TREE_CHAIN (parms1);
1087 if (! DECL_STATIC_FUNCTION_P (method))
1088 parms2 = TREE_CHAIN (parms2);
1090 if (compparms (parms1, parms2)
1091 && (!DECL_CONV_FN_P (fn)
1092 || same_type_p (TREE_TYPE (fn_type),
1093 TREE_TYPE (method_type))))
1097 if (DECL_CONTEXT (fn) == type)
1098 /* Defer to the local function. */
1103 error ("%q+#D cannot be overloaded", method);
1104 error ("with %q+#D", fn);
1107 /* We don't call duplicate_decls here to merge the
1108 declarations because that will confuse things if the
1109 methods have inline definitions. In particular, we
1110 will crash while processing the definitions. */
1115 /* A class should never have more than one destructor. */
1116 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1119 /* Add the new binding. */
1120 overload = build_overload (method, current_fns);
1121 if (using_decl && TREE_CODE (overload) == OVERLOAD)
1122 OVL_USED (overload) = true;
1125 TYPE_HAS_CONVERSION (type) = 1;
1126 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1127 push_class_level_binding (DECL_NAME (method), overload);
1133 /* We only expect to add few methods in the COMPLETE_P case, so
1134 just make room for one more method in that case. */
1136 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1138 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1140 CLASSTYPE_METHOD_VEC (type) = method_vec;
1141 if (slot == VEC_length (tree, method_vec))
1142 VEC_quick_push (tree, method_vec, overload);
1144 VEC_quick_insert (tree, method_vec, slot, overload);
1147 /* Replace the current slot. */
1148 VEC_replace (tree, method_vec, slot, overload);
1152 /* Subroutines of finish_struct. */
1154 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1155 legit, otherwise return 0. */
1158 alter_access (tree t, tree fdecl, tree access)
1162 if (!DECL_LANG_SPECIFIC (fdecl))
1163 retrofit_lang_decl (fdecl);
1165 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1167 elem = purpose_member (t, DECL_ACCESS (fdecl));
1170 if (TREE_VALUE (elem) != access)
1172 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1173 error ("conflicting access specifications for method"
1174 " %q+D, ignored", TREE_TYPE (fdecl));
1176 error ("conflicting access specifications for field %qE, ignored",
1181 /* They're changing the access to the same thing they changed
1182 it to before. That's OK. */
1188 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1189 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1195 /* Process the USING_DECL, which is a member of T. */
1198 handle_using_decl (tree using_decl, tree t)
1200 tree decl = USING_DECL_DECLS (using_decl);
1201 tree name = DECL_NAME (using_decl);
1203 = TREE_PRIVATE (using_decl) ? access_private_node
1204 : TREE_PROTECTED (using_decl) ? access_protected_node
1205 : access_public_node;
1206 tree flist = NULL_TREE;
1209 gcc_assert (!processing_template_decl && decl);
1211 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false,
1212 tf_warning_or_error);
1215 if (is_overloaded_fn (old_value))
1216 old_value = OVL_CURRENT (old_value);
1218 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1221 old_value = NULL_TREE;
1224 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1226 if (is_overloaded_fn (decl))
1231 else if (is_overloaded_fn (old_value))
1234 /* It's OK to use functions from a base when there are functions with
1235 the same name already present in the current class. */;
1238 error ("%q+D invalid in %q#T", using_decl, t);
1239 error (" because of local method %q+#D with same name",
1240 OVL_CURRENT (old_value));
1244 else if (!DECL_ARTIFICIAL (old_value))
1246 error ("%q+D invalid in %q#T", using_decl, t);
1247 error (" because of local member %q+#D with same name", old_value);
1251 /* Make type T see field decl FDECL with access ACCESS. */
1253 for (; flist; flist = OVL_NEXT (flist))
1255 add_method (t, OVL_CURRENT (flist), using_decl);
1256 alter_access (t, OVL_CURRENT (flist), access);
1259 alter_access (t, decl, access);
1262 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1263 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1264 properties of the bases. */
1267 check_bases (tree t,
1268 int* cant_have_const_ctor_p,
1269 int* no_const_asn_ref_p)
1272 bool seen_non_virtual_nearly_empty_base_p = 0;
1273 int seen_tm_mask = 0;
1276 tree field = NULL_TREE;
1278 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1279 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
1280 if (TREE_CODE (field) == FIELD_DECL)
1283 for (binfo = TYPE_BINFO (t), i = 0;
1284 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1286 tree basetype = TREE_TYPE (base_binfo);
1288 gcc_assert (COMPLETE_TYPE_P (basetype));
1290 if (CLASSTYPE_FINAL (basetype))
1291 error ("cannot derive from %<final%> base %qT in derived type %qT",
1294 /* If any base class is non-literal, so is the derived class. */
1295 if (!CLASSTYPE_LITERAL_P (basetype))
1296 CLASSTYPE_LITERAL_P (t) = false;
1298 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1299 here because the case of virtual functions but non-virtual
1300 dtor is handled in finish_struct_1. */
1301 if (!TYPE_POLYMORPHIC_P (basetype))
1302 warning (OPT_Weffc__,
1303 "base class %q#T has a non-virtual destructor", basetype);
1305 /* If the base class doesn't have copy constructors or
1306 assignment operators that take const references, then the
1307 derived class cannot have such a member automatically
1309 if (TYPE_HAS_COPY_CTOR (basetype)
1310 && ! TYPE_HAS_CONST_COPY_CTOR (basetype))
1311 *cant_have_const_ctor_p = 1;
1312 if (TYPE_HAS_COPY_ASSIGN (basetype)
1313 && !TYPE_HAS_CONST_COPY_ASSIGN (basetype))
1314 *no_const_asn_ref_p = 1;
1316 if (BINFO_VIRTUAL_P (base_binfo))
1317 /* A virtual base does not effect nearly emptiness. */
1319 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1321 if (seen_non_virtual_nearly_empty_base_p)
1322 /* And if there is more than one nearly empty base, then the
1323 derived class is not nearly empty either. */
1324 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1326 /* Remember we've seen one. */
1327 seen_non_virtual_nearly_empty_base_p = 1;
1329 else if (!is_empty_class (basetype))
1330 /* If the base class is not empty or nearly empty, then this
1331 class cannot be nearly empty. */
1332 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1334 /* A lot of properties from the bases also apply to the derived
1336 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1337 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1338 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1339 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
1340 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (basetype)
1341 || !TYPE_HAS_COPY_ASSIGN (basetype));
1342 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (basetype)
1343 || !TYPE_HAS_COPY_CTOR (basetype));
1344 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t)
1345 |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (basetype);
1346 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (basetype);
1347 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1348 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1349 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1350 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
1351 || TYPE_HAS_COMPLEX_DFLT (basetype));
1353 /* A standard-layout class is a class that:
1355 * has no non-standard-layout base classes, */
1356 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1357 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1360 /* ...has no base classes of the same type as the first non-static
1362 if (field && DECL_CONTEXT (field) == t
1363 && (same_type_ignoring_top_level_qualifiers_p
1364 (TREE_TYPE (field), basetype)))
1365 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1367 /* ...either has no non-static data members in the most-derived
1368 class and at most one base class with non-static data
1369 members, or has no base classes with non-static data
1371 for (basefield = TYPE_FIELDS (basetype); basefield;
1372 basefield = DECL_CHAIN (basefield))
1373 if (TREE_CODE (basefield) == FIELD_DECL)
1376 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1383 /* Don't bother collecting tm attributes if transactional memory
1384 support is not enabled. */
1387 tree tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (basetype));
1389 seen_tm_mask |= tm_attr_to_mask (tm_attr);
1393 /* If one of the base classes had TM attributes, and the current class
1394 doesn't define its own, then the current class inherits one. */
1395 if (seen_tm_mask && !find_tm_attribute (TYPE_ATTRIBUTES (t)))
1397 tree tm_attr = tm_mask_to_attr (seen_tm_mask & -seen_tm_mask);
1398 TYPE_ATTRIBUTES (t) = tree_cons (tm_attr, NULL, TYPE_ATTRIBUTES (t));
1402 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1403 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1404 that have had a nearly-empty virtual primary base stolen by some
1405 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1409 determine_primary_bases (tree t)
1412 tree primary = NULL_TREE;
1413 tree type_binfo = TYPE_BINFO (t);
1416 /* Determine the primary bases of our bases. */
1417 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1418 base_binfo = TREE_CHAIN (base_binfo))
1420 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1422 /* See if we're the non-virtual primary of our inheritance
1424 if (!BINFO_VIRTUAL_P (base_binfo))
1426 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1427 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1430 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1431 BINFO_TYPE (parent_primary)))
1432 /* We are the primary binfo. */
1433 BINFO_PRIMARY_P (base_binfo) = 1;
1435 /* Determine if we have a virtual primary base, and mark it so.
1437 if (primary && BINFO_VIRTUAL_P (primary))
1439 tree this_primary = copied_binfo (primary, base_binfo);
1441 if (BINFO_PRIMARY_P (this_primary))
1442 /* Someone already claimed this base. */
1443 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1448 BINFO_PRIMARY_P (this_primary) = 1;
1449 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1451 /* A virtual binfo might have been copied from within
1452 another hierarchy. As we're about to use it as a
1453 primary base, make sure the offsets match. */
1454 delta = size_diffop_loc (input_location,
1456 BINFO_OFFSET (base_binfo)),
1458 BINFO_OFFSET (this_primary)));
1460 propagate_binfo_offsets (this_primary, delta);
1465 /* First look for a dynamic direct non-virtual base. */
1466 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1468 tree basetype = BINFO_TYPE (base_binfo);
1470 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1472 primary = base_binfo;
1477 /* A "nearly-empty" virtual base class can be the primary base
1478 class, if no non-virtual polymorphic base can be found. Look for
1479 a nearly-empty virtual dynamic base that is not already a primary
1480 base of something in the hierarchy. If there is no such base,
1481 just pick the first nearly-empty virtual base. */
1483 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1484 base_binfo = TREE_CHAIN (base_binfo))
1485 if (BINFO_VIRTUAL_P (base_binfo)
1486 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1488 if (!BINFO_PRIMARY_P (base_binfo))
1490 /* Found one that is not primary. */
1491 primary = base_binfo;
1495 /* Remember the first candidate. */
1496 primary = base_binfo;
1500 /* If we've got a primary base, use it. */
1503 tree basetype = BINFO_TYPE (primary);
1505 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1506 if (BINFO_PRIMARY_P (primary))
1507 /* We are stealing a primary base. */
1508 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1509 BINFO_PRIMARY_P (primary) = 1;
1510 if (BINFO_VIRTUAL_P (primary))
1514 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1515 /* A virtual binfo might have been copied from within
1516 another hierarchy. As we're about to use it as a primary
1517 base, make sure the offsets match. */
1518 delta = size_diffop_loc (input_location, ssize_int (0),
1519 convert (ssizetype, BINFO_OFFSET (primary)));
1521 propagate_binfo_offsets (primary, delta);
1524 primary = TYPE_BINFO (basetype);
1526 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1527 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1528 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1532 /* Update the variant types of T. */
1535 fixup_type_variants (tree t)
1542 for (variants = TYPE_NEXT_VARIANT (t);
1544 variants = TYPE_NEXT_VARIANT (variants))
1546 /* These fields are in the _TYPE part of the node, not in
1547 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1548 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1549 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1550 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1551 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1553 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1555 TYPE_BINFO (variants) = TYPE_BINFO (t);
1557 /* Copy whatever these are holding today. */
1558 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1559 TYPE_METHODS (variants) = TYPE_METHODS (t);
1560 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1564 /* Early variant fixups: we apply attributes at the beginning of the class
1565 definition, and we need to fix up any variants that have already been
1566 made via elaborated-type-specifier so that check_qualified_type works. */
1569 fixup_attribute_variants (tree t)
1576 for (variants = TYPE_NEXT_VARIANT (t);
1578 variants = TYPE_NEXT_VARIANT (variants))
1580 /* These are the two fields that check_qualified_type looks at and
1581 are affected by attributes. */
1582 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1583 TYPE_ALIGN (variants) = TYPE_ALIGN (t);
1587 /* Set memoizing fields and bits of T (and its variants) for later
1591 finish_struct_bits (tree t)
1593 /* Fix up variants (if any). */
1594 fixup_type_variants (t);
1596 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1597 /* For a class w/o baseclasses, 'finish_struct' has set
1598 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1599 Similarly for a class whose base classes do not have vtables.
1600 When neither of these is true, we might have removed abstract
1601 virtuals (by providing a definition), added some (by declaring
1602 new ones), or redeclared ones from a base class. We need to
1603 recalculate what's really an abstract virtual at this point (by
1604 looking in the vtables). */
1605 get_pure_virtuals (t);
1607 /* If this type has a copy constructor or a destructor, force its
1608 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1609 nonzero. This will cause it to be passed by invisible reference
1610 and prevent it from being returned in a register. */
1611 if (type_has_nontrivial_copy_init (t)
1612 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1615 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1616 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1618 SET_TYPE_MODE (variants, BLKmode);
1619 TREE_ADDRESSABLE (variants) = 1;
1624 /* Issue warnings about T having private constructors, but no friends,
1627 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1628 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1629 non-private static member functions. */
1632 maybe_warn_about_overly_private_class (tree t)
1634 int has_member_fn = 0;
1635 int has_nonprivate_method = 0;
1638 if (!warn_ctor_dtor_privacy
1639 /* If the class has friends, those entities might create and
1640 access instances, so we should not warn. */
1641 || (CLASSTYPE_FRIEND_CLASSES (t)
1642 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1643 /* We will have warned when the template was declared; there's
1644 no need to warn on every instantiation. */
1645 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1646 /* There's no reason to even consider warning about this
1650 /* We only issue one warning, if more than one applies, because
1651 otherwise, on code like:
1654 // Oops - forgot `public:'
1660 we warn several times about essentially the same problem. */
1662 /* Check to see if all (non-constructor, non-destructor) member
1663 functions are private. (Since there are no friends or
1664 non-private statics, we can't ever call any of the private member
1666 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
1667 /* We're not interested in compiler-generated methods; they don't
1668 provide any way to call private members. */
1669 if (!DECL_ARTIFICIAL (fn))
1671 if (!TREE_PRIVATE (fn))
1673 if (DECL_STATIC_FUNCTION_P (fn))
1674 /* A non-private static member function is just like a
1675 friend; it can create and invoke private member
1676 functions, and be accessed without a class
1680 has_nonprivate_method = 1;
1681 /* Keep searching for a static member function. */
1683 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1687 if (!has_nonprivate_method && has_member_fn)
1689 /* There are no non-private methods, and there's at least one
1690 private member function that isn't a constructor or
1691 destructor. (If all the private members are
1692 constructors/destructors we want to use the code below that
1693 issues error messages specifically referring to
1694 constructors/destructors.) */
1696 tree binfo = TYPE_BINFO (t);
1698 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1699 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1701 has_nonprivate_method = 1;
1704 if (!has_nonprivate_method)
1706 warning (OPT_Wctor_dtor_privacy,
1707 "all member functions in class %qT are private", t);
1712 /* Even if some of the member functions are non-private, the class
1713 won't be useful for much if all the constructors or destructors
1714 are private: such an object can never be created or destroyed. */
1715 fn = CLASSTYPE_DESTRUCTORS (t);
1716 if (fn && TREE_PRIVATE (fn))
1718 warning (OPT_Wctor_dtor_privacy,
1719 "%q#T only defines a private destructor and has no friends",
1724 /* Warn about classes that have private constructors and no friends. */
1725 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1726 /* Implicitly generated constructors are always public. */
1727 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1728 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1730 int nonprivate_ctor = 0;
1732 /* If a non-template class does not define a copy
1733 constructor, one is defined for it, enabling it to avoid
1734 this warning. For a template class, this does not
1735 happen, and so we would normally get a warning on:
1737 template <class T> class C { private: C(); };
1739 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1740 complete non-template or fully instantiated classes have this
1742 if (!TYPE_HAS_COPY_CTOR (t))
1743 nonprivate_ctor = 1;
1745 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1747 tree ctor = OVL_CURRENT (fn);
1748 /* Ideally, we wouldn't count copy constructors (or, in
1749 fact, any constructor that takes an argument of the
1750 class type as a parameter) because such things cannot
1751 be used to construct an instance of the class unless
1752 you already have one. But, for now at least, we're
1754 if (! TREE_PRIVATE (ctor))
1756 nonprivate_ctor = 1;
1761 if (nonprivate_ctor == 0)
1763 warning (OPT_Wctor_dtor_privacy,
1764 "%q#T only defines private constructors and has no friends",
1772 gt_pointer_operator new_value;
1776 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1779 method_name_cmp (const void* m1_p, const void* m2_p)
1781 const tree *const m1 = (const tree *) m1_p;
1782 const tree *const m2 = (const tree *) m2_p;
1784 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1786 if (*m1 == NULL_TREE)
1788 if (*m2 == NULL_TREE)
1790 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1795 /* This routine compares two fields like method_name_cmp but using the
1796 pointer operator in resort_field_decl_data. */
1799 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1801 const tree *const m1 = (const tree *) m1_p;
1802 const tree *const m2 = (const tree *) m2_p;
1803 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1805 if (*m1 == NULL_TREE)
1807 if (*m2 == NULL_TREE)
1810 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1811 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1812 resort_data.new_value (&d1, resort_data.cookie);
1813 resort_data.new_value (&d2, resort_data.cookie);
1820 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1823 resort_type_method_vec (void* obj,
1824 void* orig_obj ATTRIBUTE_UNUSED ,
1825 gt_pointer_operator new_value,
1828 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1829 int len = VEC_length (tree, method_vec);
1833 /* The type conversion ops have to live at the front of the vec, so we
1835 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1836 VEC_iterate (tree, method_vec, slot, fn);
1838 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1843 resort_data.new_value = new_value;
1844 resort_data.cookie = cookie;
1845 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1846 resort_method_name_cmp);
1850 /* Warn about duplicate methods in fn_fields.
1852 Sort methods that are not special (i.e., constructors, destructors,
1853 and type conversion operators) so that we can find them faster in
1857 finish_struct_methods (tree t)
1860 VEC(tree,gc) *method_vec;
1863 method_vec = CLASSTYPE_METHOD_VEC (t);
1867 len = VEC_length (tree, method_vec);
1869 /* Clear DECL_IN_AGGR_P for all functions. */
1870 for (fn_fields = TYPE_METHODS (t); fn_fields;
1871 fn_fields = DECL_CHAIN (fn_fields))
1872 DECL_IN_AGGR_P (fn_fields) = 0;
1874 /* Issue warnings about private constructors and such. If there are
1875 no methods, then some public defaults are generated. */
1876 maybe_warn_about_overly_private_class (t);
1878 /* The type conversion ops have to live at the front of the vec, so we
1880 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1881 VEC_iterate (tree, method_vec, slot, fn_fields);
1883 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1886 qsort (VEC_address (tree, method_vec) + slot,
1887 len-slot, sizeof (tree), method_name_cmp);
1890 /* Make BINFO's vtable have N entries, including RTTI entries,
1891 vbase and vcall offsets, etc. Set its type and call the back end
1895 layout_vtable_decl (tree binfo, int n)
1900 atype = build_array_of_n_type (vtable_entry_type, n);
1901 layout_type (atype);
1903 /* We may have to grow the vtable. */
1904 vtable = get_vtbl_decl_for_binfo (binfo);
1905 if (!same_type_p (TREE_TYPE (vtable), atype))
1907 TREE_TYPE (vtable) = atype;
1908 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1909 layout_decl (vtable, 0);
1913 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1914 have the same signature. */
1917 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1919 /* One destructor overrides another if they are the same kind of
1921 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1922 && special_function_p (base_fndecl) == special_function_p (fndecl))
1924 /* But a non-destructor never overrides a destructor, nor vice
1925 versa, nor do different kinds of destructors override
1926 one-another. For example, a complete object destructor does not
1927 override a deleting destructor. */
1928 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1931 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1932 || (DECL_CONV_FN_P (fndecl)
1933 && DECL_CONV_FN_P (base_fndecl)
1934 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1935 DECL_CONV_FN_TYPE (base_fndecl))))
1937 tree types, base_types;
1938 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1939 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1940 if ((cp_type_quals (TREE_TYPE (TREE_VALUE (base_types)))
1941 == cp_type_quals (TREE_TYPE (TREE_VALUE (types))))
1942 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1948 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1952 base_derived_from (tree derived, tree base)
1956 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1958 if (probe == derived)
1960 else if (BINFO_VIRTUAL_P (probe))
1961 /* If we meet a virtual base, we can't follow the inheritance
1962 any more. See if the complete type of DERIVED contains
1963 such a virtual base. */
1964 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1970 typedef struct find_final_overrider_data_s {
1971 /* The function for which we are trying to find a final overrider. */
1973 /* The base class in which the function was declared. */
1974 tree declaring_base;
1975 /* The candidate overriders. */
1977 /* Path to most derived. */
1978 VEC(tree,heap) *path;
1979 } find_final_overrider_data;
1981 /* Add the overrider along the current path to FFOD->CANDIDATES.
1982 Returns true if an overrider was found; false otherwise. */
1985 dfs_find_final_overrider_1 (tree binfo,
1986 find_final_overrider_data *ffod,
1991 /* If BINFO is not the most derived type, try a more derived class.
1992 A definition there will overrider a definition here. */
1996 if (dfs_find_final_overrider_1
1997 (VEC_index (tree, ffod->path, depth), ffod, depth))
2001 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
2004 tree *candidate = &ffod->candidates;
2006 /* Remove any candidates overridden by this new function. */
2009 /* If *CANDIDATE overrides METHOD, then METHOD
2010 cannot override anything else on the list. */
2011 if (base_derived_from (TREE_VALUE (*candidate), binfo))
2013 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
2014 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
2015 *candidate = TREE_CHAIN (*candidate);
2017 candidate = &TREE_CHAIN (*candidate);
2020 /* Add the new function. */
2021 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
2028 /* Called from find_final_overrider via dfs_walk. */
2031 dfs_find_final_overrider_pre (tree binfo, void *data)
2033 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
2035 if (binfo == ffod->declaring_base)
2036 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
2037 VEC_safe_push (tree, heap, ffod->path, binfo);
2043 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
2045 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
2046 VEC_pop (tree, ffod->path);
2051 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
2052 FN and whose TREE_VALUE is the binfo for the base where the
2053 overriding occurs. BINFO (in the hierarchy dominated by the binfo
2054 DERIVED) is the base object in which FN is declared. */
2057 find_final_overrider (tree derived, tree binfo, tree fn)
2059 find_final_overrider_data ffod;
2061 /* Getting this right is a little tricky. This is valid:
2063 struct S { virtual void f (); };
2064 struct T { virtual void f (); };
2065 struct U : public S, public T { };
2067 even though calling `f' in `U' is ambiguous. But,
2069 struct R { virtual void f(); };
2070 struct S : virtual public R { virtual void f (); };
2071 struct T : virtual public R { virtual void f (); };
2072 struct U : public S, public T { };
2074 is not -- there's no way to decide whether to put `S::f' or
2075 `T::f' in the vtable for `R'.
2077 The solution is to look at all paths to BINFO. If we find
2078 different overriders along any two, then there is a problem. */
2079 if (DECL_THUNK_P (fn))
2080 fn = THUNK_TARGET (fn);
2082 /* Determine the depth of the hierarchy. */
2084 ffod.declaring_base = binfo;
2085 ffod.candidates = NULL_TREE;
2086 ffod.path = VEC_alloc (tree, heap, 30);
2088 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2089 dfs_find_final_overrider_post, &ffod);
2091 VEC_free (tree, heap, ffod.path);
2093 /* If there was no winner, issue an error message. */
2094 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2095 return error_mark_node;
2097 return ffod.candidates;
2100 /* Return the index of the vcall offset for FN when TYPE is used as a
2104 get_vcall_index (tree fn, tree type)
2106 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2110 FOR_EACH_VEC_ELT (tree_pair_s, indices, ix, p)
2111 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2112 || same_signature_p (fn, p->purpose))
2115 /* There should always be an appropriate index. */
2119 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2120 dominated by T. FN is the old function; VIRTUALS points to the
2121 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2122 of that entry in the list. */
2125 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2133 tree overrider_fn, overrider_target;
2134 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2135 tree over_return, base_return;
2138 /* Find the nearest primary base (possibly binfo itself) which defines
2139 this function; this is the class the caller will convert to when
2140 calling FN through BINFO. */
2141 for (b = binfo; ; b = get_primary_binfo (b))
2144 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2147 /* The nearest definition is from a lost primary. */
2148 if (BINFO_LOST_PRIMARY_P (b))
2153 /* Find the final overrider. */
2154 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2155 if (overrider == error_mark_node)
2157 error ("no unique final overrider for %qD in %qT", target_fn, t);
2160 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2162 /* Check for adjusting covariant return types. */
2163 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2164 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2166 if (POINTER_TYPE_P (over_return)
2167 && TREE_CODE (over_return) == TREE_CODE (base_return)
2168 && CLASS_TYPE_P (TREE_TYPE (over_return))
2169 && CLASS_TYPE_P (TREE_TYPE (base_return))
2170 /* If the overrider is invalid, don't even try. */
2171 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2173 /* If FN is a covariant thunk, we must figure out the adjustment
2174 to the final base FN was converting to. As OVERRIDER_TARGET might
2175 also be converting to the return type of FN, we have to
2176 combine the two conversions here. */
2177 tree fixed_offset, virtual_offset;
2179 over_return = TREE_TYPE (over_return);
2180 base_return = TREE_TYPE (base_return);
2182 if (DECL_THUNK_P (fn))
2184 gcc_assert (DECL_RESULT_THUNK_P (fn));
2185 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2186 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2189 fixed_offset = virtual_offset = NULL_TREE;
2192 /* Find the equivalent binfo within the return type of the
2193 overriding function. We will want the vbase offset from
2195 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2197 else if (!same_type_ignoring_top_level_qualifiers_p
2198 (over_return, base_return))
2200 /* There was no existing virtual thunk (which takes
2201 precedence). So find the binfo of the base function's
2202 return type within the overriding function's return type.
2203 We cannot call lookup base here, because we're inside a
2204 dfs_walk, and will therefore clobber the BINFO_MARKED
2205 flags. Fortunately we know the covariancy is valid (it
2206 has already been checked), so we can just iterate along
2207 the binfos, which have been chained in inheritance graph
2208 order. Of course it is lame that we have to repeat the
2209 search here anyway -- we should really be caching pieces
2210 of the vtable and avoiding this repeated work. */
2211 tree thunk_binfo, base_binfo;
2213 /* Find the base binfo within the overriding function's
2214 return type. We will always find a thunk_binfo, except
2215 when the covariancy is invalid (which we will have
2216 already diagnosed). */
2217 for (base_binfo = TYPE_BINFO (base_return),
2218 thunk_binfo = TYPE_BINFO (over_return);
2220 thunk_binfo = TREE_CHAIN (thunk_binfo))
2221 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2222 BINFO_TYPE (base_binfo)))
2225 /* See if virtual inheritance is involved. */
2226 for (virtual_offset = thunk_binfo;
2228 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2229 if (BINFO_VIRTUAL_P (virtual_offset))
2233 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2235 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2239 /* We convert via virtual base. Adjust the fixed
2240 offset to be from there. */
2242 size_diffop (offset,
2244 BINFO_OFFSET (virtual_offset)));
2247 /* There was an existing fixed offset, this must be
2248 from the base just converted to, and the base the
2249 FN was thunking to. */
2250 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2252 fixed_offset = offset;
2256 if (fixed_offset || virtual_offset)
2257 /* Replace the overriding function with a covariant thunk. We
2258 will emit the overriding function in its own slot as
2260 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2261 fixed_offset, virtual_offset);
2264 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2265 !DECL_THUNK_P (fn));
2267 /* If we need a covariant thunk, then we may need to adjust first_defn.
2268 The ABI specifies that the thunks emitted with a function are
2269 determined by which bases the function overrides, so we need to be
2270 sure that we're using a thunk for some overridden base; even if we
2271 know that the necessary this adjustment is zero, there may not be an
2272 appropriate zero-this-adjusment thunk for us to use since thunks for
2273 overriding virtual bases always use the vcall offset.
2275 Furthermore, just choosing any base that overrides this function isn't
2276 quite right, as this slot won't be used for calls through a type that
2277 puts a covariant thunk here. Calling the function through such a type
2278 will use a different slot, and that slot is the one that determines
2279 the thunk emitted for that base.
2281 So, keep looking until we find the base that we're really overriding
2282 in this slot: the nearest primary base that doesn't use a covariant
2283 thunk in this slot. */
2284 if (overrider_target != overrider_fn)
2286 if (BINFO_TYPE (b) == DECL_CONTEXT (overrider_target))
2287 /* We already know that the overrider needs a covariant thunk. */
2288 b = get_primary_binfo (b);
2289 for (; ; b = get_primary_binfo (b))
2291 tree main_binfo = TYPE_BINFO (BINFO_TYPE (b));
2292 tree bv = chain_index (ix, BINFO_VIRTUALS (main_binfo));
2293 if (!DECL_THUNK_P (TREE_VALUE (bv)))
2295 if (BINFO_LOST_PRIMARY_P (b))
2301 /* Assume that we will produce a thunk that convert all the way to
2302 the final overrider, and not to an intermediate virtual base. */
2303 virtual_base = NULL_TREE;
2305 /* See if we can convert to an intermediate virtual base first, and then
2306 use the vcall offset located there to finish the conversion. */
2307 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2309 /* If we find the final overrider, then we can stop
2311 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2312 BINFO_TYPE (TREE_VALUE (overrider))))
2315 /* If we find a virtual base, and we haven't yet found the
2316 overrider, then there is a virtual base between the
2317 declaring base (first_defn) and the final overrider. */
2318 if (BINFO_VIRTUAL_P (b))
2325 /* Compute the constant adjustment to the `this' pointer. The
2326 `this' pointer, when this function is called, will point at BINFO
2327 (or one of its primary bases, which are at the same offset). */
2329 /* The `this' pointer needs to be adjusted from the declaration to
2330 the nearest virtual base. */
2331 delta = size_diffop_loc (input_location,
2332 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2333 convert (ssizetype, BINFO_OFFSET (first_defn)));
2335 /* If the nearest definition is in a lost primary, we don't need an
2336 entry in our vtable. Except possibly in a constructor vtable,
2337 if we happen to get our primary back. In that case, the offset
2338 will be zero, as it will be a primary base. */
2339 delta = size_zero_node;
2341 /* The `this' pointer needs to be adjusted from pointing to
2342 BINFO to pointing at the base where the final overrider
2344 delta = size_diffop_loc (input_location,
2346 BINFO_OFFSET (TREE_VALUE (overrider))),
2347 convert (ssizetype, BINFO_OFFSET (binfo)));
2349 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2352 BV_VCALL_INDEX (*virtuals)
2353 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2355 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2357 BV_LOST_PRIMARY (*virtuals) = lost;
2360 /* Called from modify_all_vtables via dfs_walk. */
2363 dfs_modify_vtables (tree binfo, void* data)
2365 tree t = (tree) data;
2370 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2371 /* A base without a vtable needs no modification, and its bases
2372 are uninteresting. */
2373 return dfs_skip_bases;
2375 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2376 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2377 /* Don't do the primary vtable, if it's new. */
2380 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2381 /* There's no need to modify the vtable for a non-virtual primary
2382 base; we're not going to use that vtable anyhow. We do still
2383 need to do this for virtual primary bases, as they could become
2384 non-primary in a construction vtable. */
2387 make_new_vtable (t, binfo);
2389 /* Now, go through each of the virtual functions in the virtual
2390 function table for BINFO. Find the final overrider, and update
2391 the BINFO_VIRTUALS list appropriately. */
2392 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2393 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2395 ix++, virtuals = TREE_CHAIN (virtuals),
2396 old_virtuals = TREE_CHAIN (old_virtuals))
2397 update_vtable_entry_for_fn (t,
2399 BV_FN (old_virtuals),
2405 /* Update all of the primary and secondary vtables for T. Create new
2406 vtables as required, and initialize their RTTI information. Each
2407 of the functions in VIRTUALS is declared in T and may override a
2408 virtual function from a base class; find and modify the appropriate
2409 entries to point to the overriding functions. Returns a list, in
2410 declaration order, of the virtual functions that are declared in T,
2411 but do not appear in the primary base class vtable, and which
2412 should therefore be appended to the end of the vtable for T. */
2415 modify_all_vtables (tree t, tree virtuals)
2417 tree binfo = TYPE_BINFO (t);
2420 /* Update all of the vtables. */
2421 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2423 /* Add virtual functions not already in our primary vtable. These
2424 will be both those introduced by this class, and those overridden
2425 from secondary bases. It does not include virtuals merely
2426 inherited from secondary bases. */
2427 for (fnsp = &virtuals; *fnsp; )
2429 tree fn = TREE_VALUE (*fnsp);
2431 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2432 || DECL_VINDEX (fn) == error_mark_node)
2434 /* We don't need to adjust the `this' pointer when
2435 calling this function. */
2436 BV_DELTA (*fnsp) = integer_zero_node;
2437 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2439 /* This is a function not already in our vtable. Keep it. */
2440 fnsp = &TREE_CHAIN (*fnsp);
2443 /* We've already got an entry for this function. Skip it. */
2444 *fnsp = TREE_CHAIN (*fnsp);
2450 /* Get the base virtual function declarations in T that have the
2454 get_basefndecls (tree name, tree t)
2457 tree base_fndecls = NULL_TREE;
2458 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2461 /* Find virtual functions in T with the indicated NAME. */
2462 i = lookup_fnfields_1 (t, name);
2464 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2466 methods = OVL_NEXT (methods))
2468 tree method = OVL_CURRENT (methods);
2470 if (TREE_CODE (method) == FUNCTION_DECL
2471 && DECL_VINDEX (method))
2472 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2476 return base_fndecls;
2478 for (i = 0; i < n_baseclasses; i++)
2480 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2481 base_fndecls = chainon (get_basefndecls (name, basetype),
2485 return base_fndecls;
2488 /* If this declaration supersedes the declaration of
2489 a method declared virtual in the base class, then
2490 mark this field as being virtual as well. */
2493 check_for_override (tree decl, tree ctype)
2495 bool overrides_found = false;
2496 if (TREE_CODE (decl) == TEMPLATE_DECL)
2497 /* In [temp.mem] we have:
2499 A specialization of a member function template does not
2500 override a virtual function from a base class. */
2502 if ((DECL_DESTRUCTOR_P (decl)
2503 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2504 || DECL_CONV_FN_P (decl))
2505 && look_for_overrides (ctype, decl)
2506 && !DECL_STATIC_FUNCTION_P (decl))
2507 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2508 the error_mark_node so that we know it is an overriding
2511 DECL_VINDEX (decl) = decl;
2512 overrides_found = true;
2515 if (DECL_VIRTUAL_P (decl))
2517 if (!DECL_VINDEX (decl))
2518 DECL_VINDEX (decl) = error_mark_node;
2519 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2520 if (DECL_DESTRUCTOR_P (decl))
2521 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (ctype) = true;
2523 else if (DECL_FINAL_P (decl))
2524 error ("%q+#D marked final, but is not virtual", decl);
2525 if (DECL_OVERRIDE_P (decl) && !overrides_found)
2526 error ("%q+#D marked override, but does not override", decl);
2529 /* Warn about hidden virtual functions that are not overridden in t.
2530 We know that constructors and destructors don't apply. */
2533 warn_hidden (tree t)
2535 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2539 /* We go through each separately named virtual function. */
2540 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2541 VEC_iterate (tree, method_vec, i, fns);
2552 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2553 have the same name. Figure out what name that is. */
2554 name = DECL_NAME (OVL_CURRENT (fns));
2555 /* There are no possibly hidden functions yet. */
2556 base_fndecls = NULL_TREE;
2557 /* Iterate through all of the base classes looking for possibly
2558 hidden functions. */
2559 for (binfo = TYPE_BINFO (t), j = 0;
2560 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2562 tree basetype = BINFO_TYPE (base_binfo);
2563 base_fndecls = chainon (get_basefndecls (name, basetype),
2567 /* If there are no functions to hide, continue. */
2571 /* Remove any overridden functions. */
2572 for (fn = fns; fn; fn = OVL_NEXT (fn))
2574 fndecl = OVL_CURRENT (fn);
2575 if (DECL_VINDEX (fndecl))
2577 tree *prev = &base_fndecls;
2580 /* If the method from the base class has the same
2581 signature as the method from the derived class, it
2582 has been overridden. */
2583 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2584 *prev = TREE_CHAIN (*prev);
2586 prev = &TREE_CHAIN (*prev);
2590 /* Now give a warning for all base functions without overriders,
2591 as they are hidden. */
2592 while (base_fndecls)
2594 /* Here we know it is a hider, and no overrider exists. */
2595 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2596 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2597 base_fndecls = TREE_CHAIN (base_fndecls);
2602 /* Check for things that are invalid. There are probably plenty of other
2603 things we should check for also. */
2606 finish_struct_anon (tree t)
2610 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
2612 if (TREE_STATIC (field))
2614 if (TREE_CODE (field) != FIELD_DECL)
2617 if (DECL_NAME (field) == NULL_TREE
2618 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2620 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2621 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2622 for (; elt; elt = DECL_CHAIN (elt))
2624 /* We're generally only interested in entities the user
2625 declared, but we also find nested classes by noticing
2626 the TYPE_DECL that we create implicitly. You're
2627 allowed to put one anonymous union inside another,
2628 though, so we explicitly tolerate that. We use
2629 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2630 we also allow unnamed types used for defining fields. */
2631 if (DECL_ARTIFICIAL (elt)
2632 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2633 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2636 if (TREE_CODE (elt) != FIELD_DECL)
2639 permerror (input_location, "%q+#D invalid; an anonymous union can "
2640 "only have non-static data members", elt);
2642 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2643 "only have non-static data members", elt);
2647 if (TREE_PRIVATE (elt))
2650 permerror (input_location, "private member %q+#D in anonymous union", elt);
2652 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2654 else if (TREE_PROTECTED (elt))
2657 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2659 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2662 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2663 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2669 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2670 will be used later during class template instantiation.
2671 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2672 a non-static member data (FIELD_DECL), a member function
2673 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2674 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2675 When FRIEND_P is nonzero, T is either a friend class
2676 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2677 (FUNCTION_DECL, TEMPLATE_DECL). */
2680 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2682 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2683 if (CLASSTYPE_TEMPLATE_INFO (type))
2684 CLASSTYPE_DECL_LIST (type)
2685 = tree_cons (friend_p ? NULL_TREE : type,
2686 t, CLASSTYPE_DECL_LIST (type));
2689 /* This function is called from declare_virt_assop_and_dtor via
2692 DATA is a type that direcly or indirectly inherits the base
2693 represented by BINFO. If BINFO contains a virtual assignment [copy
2694 assignment or move assigment] operator or a virtual constructor,
2695 declare that function in DATA if it hasn't been already declared. */
2698 dfs_declare_virt_assop_and_dtor (tree binfo, void *data)
2700 tree bv, fn, t = (tree)data;
2701 tree opname = ansi_assopname (NOP_EXPR);
2703 gcc_assert (t && CLASS_TYPE_P (t));
2704 gcc_assert (binfo && TREE_CODE (binfo) == TREE_BINFO);
2706 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2707 /* A base without a vtable needs no modification, and its bases
2708 are uninteresting. */
2709 return dfs_skip_bases;
2711 if (BINFO_PRIMARY_P (binfo))
2712 /* If this is a primary base, then we have already looked at the
2713 virtual functions of its vtable. */
2716 for (bv = BINFO_VIRTUALS (binfo); bv; bv = TREE_CHAIN (bv))
2720 if (DECL_NAME (fn) == opname)
2722 if (CLASSTYPE_LAZY_COPY_ASSIGN (t))
2723 lazily_declare_fn (sfk_copy_assignment, t);
2724 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
2725 lazily_declare_fn (sfk_move_assignment, t);
2727 else if (DECL_DESTRUCTOR_P (fn)
2728 && CLASSTYPE_LAZY_DESTRUCTOR (t))
2729 lazily_declare_fn (sfk_destructor, t);
2735 /* If the class type T has a direct or indirect base that contains a
2736 virtual assignment operator or a virtual destructor, declare that
2737 function in T if it hasn't been already declared. */
2740 declare_virt_assop_and_dtor (tree t)
2742 if (!(TYPE_POLYMORPHIC_P (t)
2743 && (CLASSTYPE_LAZY_COPY_ASSIGN (t)
2744 || CLASSTYPE_LAZY_MOVE_ASSIGN (t)
2745 || CLASSTYPE_LAZY_DESTRUCTOR (t))))
2748 dfs_walk_all (TYPE_BINFO (t),
2749 dfs_declare_virt_assop_and_dtor,
2753 /* Create default constructors, assignment operators, and so forth for
2754 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2755 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2756 the class cannot have a default constructor, copy constructor
2757 taking a const reference argument, or an assignment operator taking
2758 a const reference, respectively. */
2761 add_implicitly_declared_members (tree t,
2762 int cant_have_const_cctor,
2763 int cant_have_const_assignment)
2765 bool move_ok = false;
2767 if (cxx_dialect >= cxx0x && !CLASSTYPE_DESTRUCTORS (t)
2768 && !TYPE_HAS_COPY_CTOR (t) && !TYPE_HAS_COPY_ASSIGN (t)
2769 && !type_has_move_constructor (t) && !type_has_move_assign (t))
2773 if (!CLASSTYPE_DESTRUCTORS (t))
2775 /* In general, we create destructors lazily. */
2776 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2778 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2779 && TYPE_FOR_JAVA (t))
2780 /* But if this is a Java class, any non-trivial destructor is
2781 invalid, even if compiler-generated. Therefore, if the
2782 destructor is non-trivial we create it now. */
2783 lazily_declare_fn (sfk_destructor, t);
2788 If there is no user-declared constructor for a class, a default
2789 constructor is implicitly declared. */
2790 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2792 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2793 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2794 if (cxx_dialect >= cxx0x)
2795 TYPE_HAS_CONSTEXPR_CTOR (t)
2796 /* This might force the declaration. */
2797 = type_has_constexpr_default_constructor (t);
2802 If a class definition does not explicitly declare a copy
2803 constructor, one is declared implicitly. */
2804 if (! TYPE_HAS_COPY_CTOR (t) && ! TYPE_FOR_JAVA (t))
2806 TYPE_HAS_COPY_CTOR (t) = 1;
2807 TYPE_HAS_CONST_COPY_CTOR (t) = !cant_have_const_cctor;
2808 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2810 CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
2813 /* If there is no assignment operator, one will be created if and
2814 when it is needed. For now, just record whether or not the type
2815 of the parameter to the assignment operator will be a const or
2816 non-const reference. */
2817 if (!TYPE_HAS_COPY_ASSIGN (t) && !TYPE_FOR_JAVA (t))
2819 TYPE_HAS_COPY_ASSIGN (t) = 1;
2820 TYPE_HAS_CONST_COPY_ASSIGN (t) = !cant_have_const_assignment;
2821 CLASSTYPE_LAZY_COPY_ASSIGN (t) = 1;
2823 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 1;
2826 /* We can't be lazy about declaring functions that might override
2827 a virtual function from a base class. */
2828 declare_virt_assop_and_dtor (t);
2831 /* Subroutine of finish_struct_1. Recursively count the number of fields
2832 in TYPE, including anonymous union members. */
2835 count_fields (tree fields)
2839 for (x = fields; x; x = DECL_CHAIN (x))
2841 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2842 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2849 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2850 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2853 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2856 for (x = fields; x; x = DECL_CHAIN (x))
2858 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2859 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2861 field_vec->elts[idx++] = x;
2866 /* FIELD is a bit-field. We are finishing the processing for its
2867 enclosing type. Issue any appropriate messages and set appropriate
2868 flags. Returns false if an error has been diagnosed. */
2871 check_bitfield_decl (tree field)
2873 tree type = TREE_TYPE (field);
2876 /* Extract the declared width of the bitfield, which has been
2877 temporarily stashed in DECL_INITIAL. */
2878 w = DECL_INITIAL (field);
2879 gcc_assert (w != NULL_TREE);
2880 /* Remove the bit-field width indicator so that the rest of the
2881 compiler does not treat that value as an initializer. */
2882 DECL_INITIAL (field) = NULL_TREE;
2884 /* Detect invalid bit-field type. */
2885 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2887 error ("bit-field %q+#D with non-integral type", field);
2888 w = error_mark_node;
2892 location_t loc = input_location;
2893 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2896 /* detect invalid field size. */
2897 input_location = DECL_SOURCE_LOCATION (field);
2898 w = cxx_constant_value (w);
2899 input_location = loc;
2901 if (TREE_CODE (w) != INTEGER_CST)
2903 error ("bit-field %q+D width not an integer constant", field);
2904 w = error_mark_node;
2906 else if (tree_int_cst_sgn (w) < 0)
2908 error ("negative width in bit-field %q+D", field);
2909 w = error_mark_node;
2911 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2913 error ("zero width for bit-field %q+D", field);
2914 w = error_mark_node;
2916 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2917 && TREE_CODE (type) != ENUMERAL_TYPE
2918 && TREE_CODE (type) != BOOLEAN_TYPE)
2919 warning (0, "width of %q+D exceeds its type", field);
2920 else if (TREE_CODE (type) == ENUMERAL_TYPE
2921 && (0 > (compare_tree_int
2922 (w, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type))))))
2923 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2926 if (w != error_mark_node)
2928 DECL_SIZE (field) = convert (bitsizetype, w);
2929 DECL_BIT_FIELD (field) = 1;
2934 /* Non-bit-fields are aligned for their type. */
2935 DECL_BIT_FIELD (field) = 0;
2936 CLEAR_DECL_C_BIT_FIELD (field);
2941 /* FIELD is a non bit-field. We are finishing the processing for its
2942 enclosing type T. Issue any appropriate messages and set appropriate
2946 check_field_decl (tree field,
2948 int* cant_have_const_ctor,
2949 int* no_const_asn_ref,
2950 int* any_default_members)
2952 tree type = strip_array_types (TREE_TYPE (field));
2954 /* In C++98 an anonymous union cannot contain any fields which would change
2955 the settings of CANT_HAVE_CONST_CTOR and friends. */
2956 if (ANON_UNION_TYPE_P (type) && cxx_dialect < cxx0x)
2958 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2959 structs. So, we recurse through their fields here. */
2960 else if (ANON_AGGR_TYPE_P (type))
2964 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2965 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2966 check_field_decl (fields, t, cant_have_const_ctor,
2967 no_const_asn_ref, any_default_members);
2969 /* Check members with class type for constructors, destructors,
2971 else if (CLASS_TYPE_P (type))
2973 /* Never let anything with uninheritable virtuals
2974 make it through without complaint. */
2975 abstract_virtuals_error (field, type);
2977 if (TREE_CODE (t) == UNION_TYPE && cxx_dialect < cxx0x)
2980 int oldcount = errorcount;
2981 if (TYPE_NEEDS_CONSTRUCTING (type))
2982 error ("member %q+#D with constructor not allowed in union",
2984 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2985 error ("member %q+#D with destructor not allowed in union", field);
2986 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
2987 error ("member %q+#D with copy assignment operator not allowed in union",
2989 if (!warned && errorcount > oldcount)
2991 inform (DECL_SOURCE_LOCATION (field), "unrestricted unions "
2992 "only available with -std=c++11 or -std=gnu++11");
2998 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2999 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3000 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
3001 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
3002 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type)
3003 || !TYPE_HAS_COPY_ASSIGN (type));
3004 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type)
3005 || !TYPE_HAS_COPY_CTOR (type));
3006 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type);
3007 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type);
3008 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type)
3009 || TYPE_HAS_COMPLEX_DFLT (type));
3012 if (TYPE_HAS_COPY_CTOR (type)
3013 && !TYPE_HAS_CONST_COPY_CTOR (type))
3014 *cant_have_const_ctor = 1;
3016 if (TYPE_HAS_COPY_ASSIGN (type)
3017 && !TYPE_HAS_CONST_COPY_ASSIGN (type))
3018 *no_const_asn_ref = 1;
3020 if (DECL_INITIAL (field) != NULL_TREE)
3022 /* `build_class_init_list' does not recognize
3024 if (TREE_CODE (t) == UNION_TYPE && *any_default_members != 0)
3025 error ("multiple fields in union %qT initialized", t);
3026 *any_default_members = 1;
3030 /* Check the data members (both static and non-static), class-scoped
3031 typedefs, etc., appearing in the declaration of T. Issue
3032 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
3033 declaration order) of access declarations; each TREE_VALUE in this
3034 list is a USING_DECL.
3036 In addition, set the following flags:
3039 The class is empty, i.e., contains no non-static data members.
3041 CANT_HAVE_CONST_CTOR_P
3042 This class cannot have an implicitly generated copy constructor
3043 taking a const reference.
3045 CANT_HAVE_CONST_ASN_REF
3046 This class cannot have an implicitly generated assignment
3047 operator taking a const reference.
3049 All of these flags should be initialized before calling this
3052 Returns a pointer to the end of the TYPE_FIELDs chain; additional
3053 fields can be added by adding to this chain. */
3056 check_field_decls (tree t, tree *access_decls,
3057 int *cant_have_const_ctor_p,
3058 int *no_const_asn_ref_p)
3063 int any_default_members;
3065 int field_access = -1;
3067 /* Assume there are no access declarations. */
3068 *access_decls = NULL_TREE;
3069 /* Assume this class has no pointer members. */
3070 has_pointers = false;
3071 /* Assume none of the members of this class have default
3073 any_default_members = 0;
3075 for (field = &TYPE_FIELDS (t); *field; field = next)
3078 tree type = TREE_TYPE (x);
3079 int this_field_access;
3081 next = &DECL_CHAIN (x);
3083 if (TREE_CODE (x) == USING_DECL)
3085 /* Save the access declarations for our caller. */
3086 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
3090 if (TREE_CODE (x) == TYPE_DECL
3091 || TREE_CODE (x) == TEMPLATE_DECL)
3094 /* If we've gotten this far, it's a data member, possibly static,
3095 or an enumerator. */
3096 DECL_CONTEXT (x) = t;
3098 /* When this goes into scope, it will be a non-local reference. */
3099 DECL_NONLOCAL (x) = 1;
3101 if (TREE_CODE (t) == UNION_TYPE)
3105 If a union contains a static data member, or a member of
3106 reference type, the program is ill-formed. */
3107 if (TREE_CODE (x) == VAR_DECL)
3109 error ("%q+D may not be static because it is a member of a union", x);
3112 if (TREE_CODE (type) == REFERENCE_TYPE)
3114 error ("%q+D may not have reference type %qT because"
3115 " it is a member of a union",
3121 /* Perform error checking that did not get done in
3123 if (TREE_CODE (type) == FUNCTION_TYPE)
3125 error ("field %q+D invalidly declared function type", x);
3126 type = build_pointer_type (type);
3127 TREE_TYPE (x) = type;
3129 else if (TREE_CODE (type) == METHOD_TYPE)
3131 error ("field %q+D invalidly declared method type", x);
3132 type = build_pointer_type (type);
3133 TREE_TYPE (x) = type;
3136 if (type == error_mark_node)
3139 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
3142 /* Now it can only be a FIELD_DECL. */
3144 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3145 CLASSTYPE_NON_AGGREGATE (t) = 1;
3147 /* If at least one non-static data member is non-literal, the whole
3148 class becomes non-literal. */
3149 if (!literal_type_p (type))
3150 CLASSTYPE_LITERAL_P (t) = false;
3152 /* A standard-layout class is a class that:
3154 has the same access control (Clause 11) for all non-static data members,
3156 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3157 if (field_access == -1)
3158 field_access = this_field_access;
3159 else if (this_field_access != field_access)
3160 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3162 /* If this is of reference type, check if it needs an init. */
3163 if (TREE_CODE (type) == REFERENCE_TYPE)
3165 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3166 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3167 if (DECL_INITIAL (x) == NULL_TREE)
3168 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3170 /* ARM $12.6.2: [A member initializer list] (or, for an
3171 aggregate, initialization by a brace-enclosed list) is the
3172 only way to initialize nonstatic const and reference
3174 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3175 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3178 type = strip_array_types (type);
3180 if (TYPE_PACKED (t))
3182 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3186 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3190 else if (DECL_C_BIT_FIELD (x)
3191 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3192 DECL_PACKED (x) = 1;
3195 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3196 /* We don't treat zero-width bitfields as making a class
3201 /* The class is non-empty. */
3202 CLASSTYPE_EMPTY_P (t) = 0;
3203 /* The class is not even nearly empty. */
3204 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3205 /* If one of the data members contains an empty class,
3207 if (CLASS_TYPE_P (type)
3208 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3209 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3212 /* This is used by -Weffc++ (see below). Warn only for pointers
3213 to members which might hold dynamic memory. So do not warn
3214 for pointers to functions or pointers to members. */
3215 if (TYPE_PTR_P (type)
3216 && !TYPE_PTRFN_P (type)
3217 && !TYPE_PTR_TO_MEMBER_P (type))
3218 has_pointers = true;
3220 if (CLASS_TYPE_P (type))
3222 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3223 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3224 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3225 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3228 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3229 CLASSTYPE_HAS_MUTABLE (t) = 1;
3231 if (! layout_pod_type_p (type))
3232 /* DR 148 now allows pointers to members (which are POD themselves),
3233 to be allowed in POD structs. */
3234 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3236 if (!std_layout_type_p (type))
3237 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3239 if (! zero_init_p (type))
3240 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3242 /* We set DECL_C_BIT_FIELD in grokbitfield.
3243 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3244 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3245 check_field_decl (x, t,
3246 cant_have_const_ctor_p,
3248 &any_default_members);
3250 /* Now that we've removed bit-field widths from DECL_INITIAL,
3251 anything left in DECL_INITIAL is an NSDMI that makes the class
3253 if (DECL_INITIAL (x))
3254 CLASSTYPE_NON_AGGREGATE (t) = true;
3256 /* If any field is const, the structure type is pseudo-const. */
3257 if (CP_TYPE_CONST_P (type))
3259 C_TYPE_FIELDS_READONLY (t) = 1;
3260 if (DECL_INITIAL (x) == NULL_TREE)
3261 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3263 /* ARM $12.6.2: [A member initializer list] (or, for an
3264 aggregate, initialization by a brace-enclosed list) is the
3265 only way to initialize nonstatic const and reference
3267 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3268 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3270 /* A field that is pseudo-const makes the structure likewise. */
3271 else if (CLASS_TYPE_P (type))
3273 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3274 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3275 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3276 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3279 /* Core issue 80: A nonstatic data member is required to have a
3280 different name from the class iff the class has a
3281 user-declared constructor. */
3282 if (constructor_name_p (DECL_NAME (x), t)
3283 && TYPE_HAS_USER_CONSTRUCTOR (t))
3284 permerror (input_location, "field %q+#D with same name as class", x);
3287 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3288 it should also define a copy constructor and an assignment operator to
3289 implement the correct copy semantic (deep vs shallow, etc.). As it is
3290 not feasible to check whether the constructors do allocate dynamic memory
3291 and store it within members, we approximate the warning like this:
3293 -- Warn only if there are members which are pointers
3294 -- Warn only if there is a non-trivial constructor (otherwise,
3295 there cannot be memory allocated).
3296 -- Warn only if there is a non-trivial destructor. We assume that the
3297 user at least implemented the cleanup correctly, and a destructor
3298 is needed to free dynamic memory.
3300 This seems enough for practical purposes. */
3303 && TYPE_HAS_USER_CONSTRUCTOR (t)
3304 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3305 && !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
3307 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3309 if (! TYPE_HAS_COPY_CTOR (t))
3311 warning (OPT_Weffc__,
3312 " but does not override %<%T(const %T&)%>", t, t);
3313 if (!TYPE_HAS_COPY_ASSIGN (t))
3314 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3316 else if (! TYPE_HAS_COPY_ASSIGN (t))
3317 warning (OPT_Weffc__,
3318 " but does not override %<operator=(const %T&)%>", t);
3321 /* Non-static data member initializers make the default constructor
3323 if (any_default_members)
3325 TYPE_NEEDS_CONSTRUCTING (t) = true;
3326 TYPE_HAS_COMPLEX_DFLT (t) = true;
3329 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3331 TYPE_PACKED (t) = 0;
3333 /* Check anonymous struct/anonymous union fields. */
3334 finish_struct_anon (t);
3336 /* We've built up the list of access declarations in reverse order.
3338 *access_decls = nreverse (*access_decls);
3341 /* If TYPE is an empty class type, records its OFFSET in the table of
3345 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3349 if (!is_empty_class (type))
3352 /* Record the location of this empty object in OFFSETS. */
3353 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3355 n = splay_tree_insert (offsets,
3356 (splay_tree_key) offset,
3357 (splay_tree_value) NULL_TREE);
3358 n->value = ((splay_tree_value)
3359 tree_cons (NULL_TREE,
3366 /* Returns nonzero if TYPE is an empty class type and there is
3367 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3370 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3375 if (!is_empty_class (type))
3378 /* Record the location of this empty object in OFFSETS. */
3379 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3383 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3384 if (same_type_p (TREE_VALUE (t), type))
3390 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3391 F for every subobject, passing it the type, offset, and table of
3392 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3395 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3396 than MAX_OFFSET will not be walked.
3398 If F returns a nonzero value, the traversal ceases, and that value
3399 is returned. Otherwise, returns zero. */
3402 walk_subobject_offsets (tree type,
3403 subobject_offset_fn f,
3410 tree type_binfo = NULL_TREE;
3412 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3414 if (max_offset && INT_CST_LT (max_offset, offset))
3417 if (type == error_mark_node)
3422 if (abi_version_at_least (2))
3424 type = BINFO_TYPE (type);
3427 if (CLASS_TYPE_P (type))
3433 /* Avoid recursing into objects that are not interesting. */
3434 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3437 /* Record the location of TYPE. */
3438 r = (*f) (type, offset, offsets);
3442 /* Iterate through the direct base classes of TYPE. */
3444 type_binfo = TYPE_BINFO (type);
3445 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3449 if (abi_version_at_least (2)
3450 && BINFO_VIRTUAL_P (binfo))
3454 && BINFO_VIRTUAL_P (binfo)
3455 && !BINFO_PRIMARY_P (binfo))
3458 if (!abi_version_at_least (2))
3459 binfo_offset = size_binop (PLUS_EXPR,
3461 BINFO_OFFSET (binfo));
3465 /* We cannot rely on BINFO_OFFSET being set for the base
3466 class yet, but the offsets for direct non-virtual
3467 bases can be calculated by going back to the TYPE. */
3468 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3469 binfo_offset = size_binop (PLUS_EXPR,
3471 BINFO_OFFSET (orig_binfo));
3474 r = walk_subobject_offsets (binfo,
3479 (abi_version_at_least (2)
3480 ? /*vbases_p=*/0 : vbases_p));
3485 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3488 VEC(tree,gc) *vbases;
3490 /* Iterate through the virtual base classes of TYPE. In G++
3491 3.2, we included virtual bases in the direct base class
3492 loop above, which results in incorrect results; the
3493 correct offsets for virtual bases are only known when
3494 working with the most derived type. */
3496 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3497 VEC_iterate (tree, vbases, ix, binfo); ix++)
3499 r = walk_subobject_offsets (binfo,
3501 size_binop (PLUS_EXPR,
3503 BINFO_OFFSET (binfo)),
3512 /* We still have to walk the primary base, if it is
3513 virtual. (If it is non-virtual, then it was walked
3515 tree vbase = get_primary_binfo (type_binfo);
3517 if (vbase && BINFO_VIRTUAL_P (vbase)
3518 && BINFO_PRIMARY_P (vbase)
3519 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3521 r = (walk_subobject_offsets
3523 offsets, max_offset, /*vbases_p=*/0));
3530 /* Iterate through the fields of TYPE. */
3531 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
3532 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3536 if (abi_version_at_least (2))
3537 field_offset = byte_position (field);
3539 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3540 field_offset = DECL_FIELD_OFFSET (field);
3542 r = walk_subobject_offsets (TREE_TYPE (field),
3544 size_binop (PLUS_EXPR,
3554 else if (TREE_CODE (type) == ARRAY_TYPE)
3556 tree element_type = strip_array_types (type);
3557 tree domain = TYPE_DOMAIN (type);
3560 /* Avoid recursing into objects that are not interesting. */
3561 if (!CLASS_TYPE_P (element_type)
3562 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3565 /* Step through each of the elements in the array. */
3566 for (index = size_zero_node;
3567 /* G++ 3.2 had an off-by-one error here. */
3568 (abi_version_at_least (2)
3569 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3570 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3571 index = size_binop (PLUS_EXPR, index, size_one_node))
3573 r = walk_subobject_offsets (TREE_TYPE (type),
3581 offset = size_binop (PLUS_EXPR, offset,
3582 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3583 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3584 there's no point in iterating through the remaining
3585 elements of the array. */
3586 if (max_offset && INT_CST_LT (max_offset, offset))
3594 /* Record all of the empty subobjects of TYPE (either a type or a
3595 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3596 is being placed at OFFSET; otherwise, it is a base class that is
3597 being placed at OFFSET. */
3600 record_subobject_offsets (tree type,
3603 bool is_data_member)
3606 /* If recording subobjects for a non-static data member or a
3607 non-empty base class , we do not need to record offsets beyond
3608 the size of the biggest empty class. Additional data members
3609 will go at the end of the class. Additional base classes will go
3610 either at offset zero (if empty, in which case they cannot
3611 overlap with offsets past the size of the biggest empty class) or
3612 at the end of the class.
3614 However, if we are placing an empty base class, then we must record
3615 all offsets, as either the empty class is at offset zero (where
3616 other empty classes might later be placed) or at the end of the
3617 class (where other objects might then be placed, so other empty
3618 subobjects might later overlap). */
3620 || !is_empty_class (BINFO_TYPE (type)))
3621 max_offset = sizeof_biggest_empty_class;
3623 max_offset = NULL_TREE;
3624 walk_subobject_offsets (type, record_subobject_offset, offset,
3625 offsets, max_offset, is_data_member);
3628 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3629 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3630 virtual bases of TYPE are examined. */
3633 layout_conflict_p (tree type,
3638 splay_tree_node max_node;
3640 /* Get the node in OFFSETS that indicates the maximum offset where
3641 an empty subobject is located. */
3642 max_node = splay_tree_max (offsets);
3643 /* If there aren't any empty subobjects, then there's no point in
3644 performing this check. */
3648 return walk_subobject_offsets (type, check_subobject_offset, offset,
3649 offsets, (tree) (max_node->key),
3653 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3654 non-static data member of the type indicated by RLI. BINFO is the
3655 binfo corresponding to the base subobject, OFFSETS maps offsets to
3656 types already located at those offsets. This function determines
3657 the position of the DECL. */
3660 layout_nonempty_base_or_field (record_layout_info rli,
3665 tree offset = NULL_TREE;
3671 /* For the purposes of determining layout conflicts, we want to
3672 use the class type of BINFO; TREE_TYPE (DECL) will be the
3673 CLASSTYPE_AS_BASE version, which does not contain entries for
3674 zero-sized bases. */
3675 type = TREE_TYPE (binfo);
3680 type = TREE_TYPE (decl);
3684 /* Try to place the field. It may take more than one try if we have
3685 a hard time placing the field without putting two objects of the
3686 same type at the same address. */
3689 struct record_layout_info_s old_rli = *rli;
3691 /* Place this field. */
3692 place_field (rli, decl);
3693 offset = byte_position (decl);
3695 /* We have to check to see whether or not there is already
3696 something of the same type at the offset we're about to use.
3697 For example, consider:
3700 struct T : public S { int i; };
3701 struct U : public S, public T {};
3703 Here, we put S at offset zero in U. Then, we can't put T at
3704 offset zero -- its S component would be at the same address
3705 as the S we already allocated. So, we have to skip ahead.
3706 Since all data members, including those whose type is an
3707 empty class, have nonzero size, any overlap can happen only
3708 with a direct or indirect base-class -- it can't happen with
3710 /* In a union, overlap is permitted; all members are placed at
3712 if (TREE_CODE (rli->t) == UNION_TYPE)
3714 /* G++ 3.2 did not check for overlaps when placing a non-empty
3716 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3718 if (layout_conflict_p (field_p ? type : binfo, offset,
3721 /* Strip off the size allocated to this field. That puts us
3722 at the first place we could have put the field with
3723 proper alignment. */
3726 /* Bump up by the alignment required for the type. */
3728 = size_binop (PLUS_EXPR, rli->bitpos,
3730 ? CLASSTYPE_ALIGN (type)
3731 : TYPE_ALIGN (type)));
3732 normalize_rli (rli);
3735 /* There was no conflict. We're done laying out this field. */
3739 /* Now that we know where it will be placed, update its
3741 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3742 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3743 this point because their BINFO_OFFSET is copied from another
3744 hierarchy. Therefore, we may not need to add the entire
3746 propagate_binfo_offsets (binfo,
3747 size_diffop_loc (input_location,
3748 convert (ssizetype, offset),
3750 BINFO_OFFSET (binfo))));
3753 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3756 empty_base_at_nonzero_offset_p (tree type,
3758 splay_tree offsets ATTRIBUTE_UNUSED)
3760 return is_empty_class (type) && !integer_zerop (offset);
3763 /* Layout the empty base BINFO. EOC indicates the byte currently just
3764 past the end of the class, and should be correctly aligned for a
3765 class of the type indicated by BINFO; OFFSETS gives the offsets of
3766 the empty bases allocated so far. T is the most derived
3767 type. Return nonzero iff we added it at the end. */
3770 layout_empty_base (record_layout_info rli, tree binfo,
3771 tree eoc, splay_tree offsets)
3774 tree basetype = BINFO_TYPE (binfo);
3777 /* This routine should only be used for empty classes. */
3778 gcc_assert (is_empty_class (basetype));
3779 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3781 if (!integer_zerop (BINFO_OFFSET (binfo)))
3783 if (abi_version_at_least (2))
3784 propagate_binfo_offsets
3785 (binfo, size_diffop_loc (input_location,
3786 size_zero_node, BINFO_OFFSET (binfo)));
3789 "offset of empty base %qT may not be ABI-compliant and may"
3790 "change in a future version of GCC",
3791 BINFO_TYPE (binfo));
3794 /* This is an empty base class. We first try to put it at offset
3796 if (layout_conflict_p (binfo,
3797 BINFO_OFFSET (binfo),
3801 /* That didn't work. Now, we move forward from the next
3802 available spot in the class. */
3804 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3807 if (!layout_conflict_p (binfo,
3808 BINFO_OFFSET (binfo),
3811 /* We finally found a spot where there's no overlap. */
3814 /* There's overlap here, too. Bump along to the next spot. */
3815 propagate_binfo_offsets (binfo, alignment);
3819 if (CLASSTYPE_USER_ALIGN (basetype))
3821 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3823 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3824 TYPE_USER_ALIGN (rli->t) = 1;
3830 /* Layout the base given by BINFO in the class indicated by RLI.
3831 *BASE_ALIGN is a running maximum of the alignments of
3832 any base class. OFFSETS gives the location of empty base
3833 subobjects. T is the most derived type. Return nonzero if the new
3834 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3835 *NEXT_FIELD, unless BINFO is for an empty base class.
3837 Returns the location at which the next field should be inserted. */
3840 build_base_field (record_layout_info rli, tree binfo,
3841 splay_tree offsets, tree *next_field)
3844 tree basetype = BINFO_TYPE (binfo);
3846 if (!COMPLETE_TYPE_P (basetype))
3847 /* This error is now reported in xref_tag, thus giving better
3848 location information. */
3851 /* Place the base class. */
3852 if (!is_empty_class (basetype))
3856 /* The containing class is non-empty because it has a non-empty
3858 CLASSTYPE_EMPTY_P (t) = 0;
3860 /* Create the FIELD_DECL. */
3861 decl = build_decl (input_location,
3862 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3863 DECL_ARTIFICIAL (decl) = 1;
3864 DECL_IGNORED_P (decl) = 1;
3865 DECL_FIELD_CONTEXT (decl) = t;
3866 if (CLASSTYPE_AS_BASE (basetype))
3868 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3869 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3870 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3871 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3872 DECL_MODE (decl) = TYPE_MODE (basetype);
3873 DECL_FIELD_IS_BASE (decl) = 1;
3875 /* Try to place the field. It may take more than one try if we
3876 have a hard time placing the field without putting two
3877 objects of the same type at the same address. */
3878 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3879 /* Add the new FIELD_DECL to the list of fields for T. */
3880 DECL_CHAIN (decl) = *next_field;
3882 next_field = &DECL_CHAIN (decl);
3890 /* On some platforms (ARM), even empty classes will not be
3892 eoc = round_up_loc (input_location,
3893 rli_size_unit_so_far (rli),
3894 CLASSTYPE_ALIGN_UNIT (basetype));
3895 atend = layout_empty_base (rli, binfo, eoc, offsets);
3896 /* A nearly-empty class "has no proper base class that is empty,
3897 not morally virtual, and at an offset other than zero." */
3898 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3901 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3902 /* The check above (used in G++ 3.2) is insufficient because
3903 an empty class placed at offset zero might itself have an
3904 empty base at a nonzero offset. */
3905 else if (walk_subobject_offsets (basetype,
3906 empty_base_at_nonzero_offset_p,
3909 /*max_offset=*/NULL_TREE,
3912 if (abi_version_at_least (2))
3913 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3916 "class %qT will be considered nearly empty in a "
3917 "future version of GCC", t);
3921 /* We do not create a FIELD_DECL for empty base classes because
3922 it might overlap some other field. We want to be able to
3923 create CONSTRUCTORs for the class by iterating over the
3924 FIELD_DECLs, and the back end does not handle overlapping
3927 /* An empty virtual base causes a class to be non-empty
3928 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3929 here because that was already done when the virtual table
3930 pointer was created. */
3933 /* Record the offsets of BINFO and its base subobjects. */
3934 record_subobject_offsets (binfo,
3935 BINFO_OFFSET (binfo),
3937 /*is_data_member=*/false);
3942 /* Layout all of the non-virtual base classes. Record empty
3943 subobjects in OFFSETS. T is the most derived type. Return nonzero
3944 if the type cannot be nearly empty. The fields created
3945 corresponding to the base classes will be inserted at
3949 build_base_fields (record_layout_info rli,
3950 splay_tree offsets, tree *next_field)
3952 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3955 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3958 /* The primary base class is always allocated first. */
3959 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3960 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3961 offsets, next_field);
3963 /* Now allocate the rest of the bases. */
3964 for (i = 0; i < n_baseclasses; ++i)
3968 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3970 /* The primary base was already allocated above, so we don't
3971 need to allocate it again here. */
3972 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3975 /* Virtual bases are added at the end (a primary virtual base
3976 will have already been added). */
3977 if (BINFO_VIRTUAL_P (base_binfo))
3980 next_field = build_base_field (rli, base_binfo,
3981 offsets, next_field);
3985 /* Go through the TYPE_METHODS of T issuing any appropriate
3986 diagnostics, figuring out which methods override which other
3987 methods, and so forth. */
3990 check_methods (tree t)
3994 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
3996 check_for_override (x, t);
3997 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3998 error ("initializer specified for non-virtual method %q+D", x);
3999 /* The name of the field is the original field name
4000 Save this in auxiliary field for later overloading. */
4001 if (DECL_VINDEX (x))
4003 TYPE_POLYMORPHIC_P (t) = 1;
4004 if (DECL_PURE_VIRTUAL_P (x))
4005 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
4007 /* All user-provided destructors are non-trivial.
4008 Constructors and assignment ops are handled in
4009 grok_special_member_properties. */
4010 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
4011 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
4015 /* FN is a constructor or destructor. Clone the declaration to create
4016 a specialized in-charge or not-in-charge version, as indicated by
4020 build_clone (tree fn, tree name)
4025 /* Copy the function. */
4026 clone = copy_decl (fn);
4027 /* Reset the function name. */
4028 DECL_NAME (clone) = name;
4029 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
4030 /* Remember where this function came from. */
4031 DECL_ABSTRACT_ORIGIN (clone) = fn;
4032 /* Make it easy to find the CLONE given the FN. */
4033 DECL_CHAIN (clone) = DECL_CHAIN (fn);
4034 DECL_CHAIN (fn) = clone;
4036 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
4037 if (TREE_CODE (clone) == TEMPLATE_DECL)
4039 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
4040 DECL_TEMPLATE_RESULT (clone) = result;
4041 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
4042 DECL_TI_TEMPLATE (result) = clone;
4043 TREE_TYPE (clone) = TREE_TYPE (result);
4047 DECL_CLONED_FUNCTION (clone) = fn;
4048 /* There's no pending inline data for this function. */
4049 DECL_PENDING_INLINE_INFO (clone) = NULL;
4050 DECL_PENDING_INLINE_P (clone) = 0;
4052 /* The base-class destructor is not virtual. */
4053 if (name == base_dtor_identifier)
4055 DECL_VIRTUAL_P (clone) = 0;
4056 if (TREE_CODE (clone) != TEMPLATE_DECL)
4057 DECL_VINDEX (clone) = NULL_TREE;
4060 /* If there was an in-charge parameter, drop it from the function
4062 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4068 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4069 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4070 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
4071 /* Skip the `this' parameter. */
4072 parmtypes = TREE_CHAIN (parmtypes);
4073 /* Skip the in-charge parameter. */
4074 parmtypes = TREE_CHAIN (parmtypes);
4075 /* And the VTT parm, in a complete [cd]tor. */
4076 if (DECL_HAS_VTT_PARM_P (fn)
4077 && ! DECL_NEEDS_VTT_PARM_P (clone))
4078 parmtypes = TREE_CHAIN (parmtypes);
4079 /* If this is subobject constructor or destructor, add the vtt
4082 = build_method_type_directly (basetype,
4083 TREE_TYPE (TREE_TYPE (clone)),
4086 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
4089 = cp_build_type_attribute_variant (TREE_TYPE (clone),
4090 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
4093 /* Copy the function parameters. */
4094 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
4095 /* Remove the in-charge parameter. */
4096 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4098 DECL_CHAIN (DECL_ARGUMENTS (clone))
4099 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4100 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
4102 /* And the VTT parm, in a complete [cd]tor. */
4103 if (DECL_HAS_VTT_PARM_P (fn))
4105 if (DECL_NEEDS_VTT_PARM_P (clone))
4106 DECL_HAS_VTT_PARM_P (clone) = 1;
4109 DECL_CHAIN (DECL_ARGUMENTS (clone))
4110 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4111 DECL_HAS_VTT_PARM_P (clone) = 0;
4115 for (parms = DECL_ARGUMENTS (clone); parms; parms = DECL_CHAIN (parms))
4117 DECL_CONTEXT (parms) = clone;
4118 cxx_dup_lang_specific_decl (parms);
4121 /* Create the RTL for this function. */
4122 SET_DECL_RTL (clone, NULL);
4123 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
4126 note_decl_for_pch (clone);
4131 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4132 not invoke this function directly.
4134 For a non-thunk function, returns the address of the slot for storing
4135 the function it is a clone of. Otherwise returns NULL_TREE.
4137 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4138 cloned_function is unset. This is to support the separate
4139 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4140 on a template makes sense, but not the former. */
4143 decl_cloned_function_p (const_tree decl, bool just_testing)
4147 decl = STRIP_TEMPLATE (decl);
4149 if (TREE_CODE (decl) != FUNCTION_DECL
4150 || !DECL_LANG_SPECIFIC (decl)
4151 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
4153 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4155 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
4161 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
4162 if (just_testing && *ptr == NULL_TREE)
4168 /* Produce declarations for all appropriate clones of FN. If
4169 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4170 CLASTYPE_METHOD_VEC as well. */
4173 clone_function_decl (tree fn, int update_method_vec_p)
4177 /* Avoid inappropriate cloning. */
4179 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (fn)))
4182 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4184 /* For each constructor, we need two variants: an in-charge version
4185 and a not-in-charge version. */
4186 clone = build_clone (fn, complete_ctor_identifier);
4187 if (update_method_vec_p)
4188 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4189 clone = build_clone (fn, base_ctor_identifier);
4190 if (update_method_vec_p)
4191 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4195 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4197 /* For each destructor, we need three variants: an in-charge
4198 version, a not-in-charge version, and an in-charge deleting
4199 version. We clone the deleting version first because that
4200 means it will go second on the TYPE_METHODS list -- and that
4201 corresponds to the correct layout order in the virtual
4204 For a non-virtual destructor, we do not build a deleting
4206 if (DECL_VIRTUAL_P (fn))
4208 clone = build_clone (fn, deleting_dtor_identifier);
4209 if (update_method_vec_p)
4210 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4212 clone = build_clone (fn, complete_dtor_identifier);
4213 if (update_method_vec_p)
4214 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4215 clone = build_clone (fn, base_dtor_identifier);
4216 if (update_method_vec_p)
4217 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4220 /* Note that this is an abstract function that is never emitted. */
4221 DECL_ABSTRACT (fn) = 1;
4224 /* DECL is an in charge constructor, which is being defined. This will
4225 have had an in class declaration, from whence clones were
4226 declared. An out-of-class definition can specify additional default
4227 arguments. As it is the clones that are involved in overload
4228 resolution, we must propagate the information from the DECL to its
4232 adjust_clone_args (tree decl)
4236 for (clone = DECL_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4237 clone = DECL_CHAIN (clone))
4239 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4240 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4241 tree decl_parms, clone_parms;
4243 clone_parms = orig_clone_parms;
4245 /* Skip the 'this' parameter. */
4246 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4247 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4249 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4250 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4251 if (DECL_HAS_VTT_PARM_P (decl))
4252 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4254 clone_parms = orig_clone_parms;
4255 if (DECL_HAS_VTT_PARM_P (clone))
4256 clone_parms = TREE_CHAIN (clone_parms);
4258 for (decl_parms = orig_decl_parms; decl_parms;
4259 decl_parms = TREE_CHAIN (decl_parms),
4260 clone_parms = TREE_CHAIN (clone_parms))
4262 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4263 TREE_TYPE (clone_parms)));
4265 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4267 /* A default parameter has been added. Adjust the
4268 clone's parameters. */
4269 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4270 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4271 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4274 clone_parms = orig_decl_parms;
4276 if (DECL_HAS_VTT_PARM_P (clone))
4278 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4279 TREE_VALUE (orig_clone_parms),
4281 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4283 type = build_method_type_directly (basetype,
4284 TREE_TYPE (TREE_TYPE (clone)),
4287 type = build_exception_variant (type, exceptions);
4289 type = cp_build_type_attribute_variant (type, attrs);
4290 TREE_TYPE (clone) = type;
4292 clone_parms = NULL_TREE;
4296 gcc_assert (!clone_parms);
4300 /* For each of the constructors and destructors in T, create an
4301 in-charge and not-in-charge variant. */
4304 clone_constructors_and_destructors (tree t)
4308 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4310 if (!CLASSTYPE_METHOD_VEC (t))
4313 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4314 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4315 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4316 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4319 /* Subroutine of set_one_vmethod_tm_attributes. Search base classes
4320 of TYPE for virtual functions which FNDECL overrides. Return a
4321 mask of the tm attributes found therein. */
4324 look_for_tm_attr_overrides (tree type, tree fndecl)
4326 tree binfo = TYPE_BINFO (type);
4330 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ++ix)
4332 tree o, basetype = BINFO_TYPE (base_binfo);
4334 if (!TYPE_POLYMORPHIC_P (basetype))
4337 o = look_for_overrides_here (basetype, fndecl);
4339 found |= tm_attr_to_mask (find_tm_attribute
4340 (TYPE_ATTRIBUTES (TREE_TYPE (o))));
4342 found |= look_for_tm_attr_overrides (basetype, fndecl);
4348 /* Subroutine of set_method_tm_attributes. Handle the checks and
4349 inheritance for one virtual method FNDECL. */
4352 set_one_vmethod_tm_attributes (tree type, tree fndecl)
4357 found = look_for_tm_attr_overrides (type, fndecl);
4359 /* If FNDECL doesn't actually override anything (i.e. T is the
4360 class that first declares FNDECL virtual), then we're done. */
4364 tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (TREE_TYPE (fndecl)));
4365 have = tm_attr_to_mask (tm_attr);
4367 /* Intel STM Language Extension 3.0, Section 4.2 table 4:
4368 tm_pure must match exactly, otherwise no weakening of
4369 tm_safe > tm_callable > nothing. */
4370 /* ??? The tm_pure attribute didn't make the transition to the
4371 multivendor language spec. */
4372 if (have == TM_ATTR_PURE)
4374 if (found != TM_ATTR_PURE)
4380 /* If the overridden function is tm_pure, then FNDECL must be. */
4381 else if (found == TM_ATTR_PURE && tm_attr)
4383 /* Look for base class combinations that cannot be satisfied. */
4384 else if (found != TM_ATTR_PURE && (found & TM_ATTR_PURE))
4386 found &= ~TM_ATTR_PURE;
4388 error_at (DECL_SOURCE_LOCATION (fndecl),
4389 "method overrides both %<transaction_pure%> and %qE methods",
4390 tm_mask_to_attr (found));
4392 /* If FNDECL did not declare an attribute, then inherit the most
4394 else if (tm_attr == NULL)
4396 apply_tm_attr (fndecl, tm_mask_to_attr (found & -found));
4398 /* Otherwise validate that we're not weaker than a function
4399 that is being overridden. */
4403 if (found <= TM_ATTR_CALLABLE && have > found)
4409 error_at (DECL_SOURCE_LOCATION (fndecl),
4410 "method declared %qE overriding %qE method",
4411 tm_attr, tm_mask_to_attr (found));
4414 /* For each of the methods in T, propagate a class-level tm attribute. */
4417 set_method_tm_attributes (tree t)
4419 tree class_tm_attr, fndecl;
4421 /* Don't bother collecting tm attributes if transactional memory
4422 support is not enabled. */
4426 /* Process virtual methods first, as they inherit directly from the
4427 base virtual function and also require validation of new attributes. */
4428 if (TYPE_CONTAINS_VPTR_P (t))
4431 for (vchain = BINFO_VIRTUALS (TYPE_BINFO (t)); vchain;
4432 vchain = TREE_CHAIN (vchain))
4433 set_one_vmethod_tm_attributes (t, BV_FN (vchain));
4436 /* If the class doesn't have an attribute, nothing more to do. */
4437 class_tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (t));
4438 if (class_tm_attr == NULL)
4441 /* Any method that does not yet have a tm attribute inherits
4442 the one from the class. */
4443 for (fndecl = TYPE_METHODS (t); fndecl; fndecl = TREE_CHAIN (fndecl))
4445 if (!find_tm_attribute (TYPE_ATTRIBUTES (TREE_TYPE (fndecl))))
4446 apply_tm_attr (fndecl, class_tm_attr);
4450 /* Returns true iff class T has a user-defined constructor other than
4451 the default constructor. */
4454 type_has_user_nondefault_constructor (tree t)
4458 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4461 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4463 tree fn = OVL_CURRENT (fns);
4464 if (!DECL_ARTIFICIAL (fn)
4465 && (TREE_CODE (fn) == TEMPLATE_DECL
4466 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4474 /* Returns the defaulted constructor if T has one. Otherwise, returns
4478 in_class_defaulted_default_constructor (tree t)
4482 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4485 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4487 tree fn = OVL_CURRENT (fns);
4489 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4491 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4492 while (args && TREE_PURPOSE (args))
4493 args = TREE_CHAIN (args);
4494 if (!args || args == void_list_node)
4502 /* Returns true iff FN is a user-provided function, i.e. user-declared
4503 and not defaulted at its first declaration; or explicit, private,
4504 protected, or non-const. */
4507 user_provided_p (tree fn)
4509 if (TREE_CODE (fn) == TEMPLATE_DECL)
4512 return (!DECL_ARTIFICIAL (fn)
4513 && !DECL_DEFAULTED_IN_CLASS_P (fn));
4516 /* Returns true iff class T has a user-provided constructor. */
4519 type_has_user_provided_constructor (tree t)
4523 if (!CLASS_TYPE_P (t))
4526 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4529 /* This can happen in error cases; avoid crashing. */
4530 if (!CLASSTYPE_METHOD_VEC (t))
4533 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4534 if (user_provided_p (OVL_CURRENT (fns)))
4540 /* Returns true iff class T has a user-provided default constructor. */
4543 type_has_user_provided_default_constructor (tree t)
4547 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4550 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4552 tree fn = OVL_CURRENT (fns);
4553 if (TREE_CODE (fn) == FUNCTION_DECL
4554 && user_provided_p (fn)
4555 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)))
4562 /* If default-initialization leaves part of TYPE uninitialized, returns
4563 a DECL for the field or TYPE itself (DR 253). */
4566 default_init_uninitialized_part (tree type)
4571 type = strip_array_types (type);
4572 if (!CLASS_TYPE_P (type))
4574 if (type_has_user_provided_default_constructor (type))
4576 for (binfo = TYPE_BINFO (type), i = 0;
4577 BINFO_BASE_ITERATE (binfo, i, t); ++i)
4579 r = default_init_uninitialized_part (BINFO_TYPE (t));
4583 for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t))
4584 if (TREE_CODE (t) == FIELD_DECL
4585 && !DECL_ARTIFICIAL (t)
4586 && !DECL_INITIAL (t))
4588 r = default_init_uninitialized_part (TREE_TYPE (t));
4590 return DECL_P (r) ? r : t;
4596 /* Returns true iff for class T, a trivial synthesized default constructor
4597 would be constexpr. */
4600 trivial_default_constructor_is_constexpr (tree t)
4602 /* A defaulted trivial default constructor is constexpr
4603 if there is nothing to initialize. */
4604 gcc_assert (!TYPE_HAS_COMPLEX_DFLT (t));
4605 return is_really_empty_class (t);
4608 /* Returns true iff class T has a constexpr default constructor. */
4611 type_has_constexpr_default_constructor (tree t)
4615 if (!CLASS_TYPE_P (t))
4617 /* The caller should have stripped an enclosing array. */
4618 gcc_assert (TREE_CODE (t) != ARRAY_TYPE);
4621 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t))
4623 if (!TYPE_HAS_COMPLEX_DFLT (t))
4624 return trivial_default_constructor_is_constexpr (t);
4625 /* Non-trivial, we need to check subobject constructors. */
4626 lazily_declare_fn (sfk_constructor, t);
4628 fns = locate_ctor (t);
4629 return (fns && DECL_DECLARED_CONSTEXPR_P (fns));
4632 /* Returns true iff class TYPE has a virtual destructor. */
4635 type_has_virtual_destructor (tree type)
4639 if (!CLASS_TYPE_P (type))
4642 gcc_assert (COMPLETE_TYPE_P (type));
4643 dtor = CLASSTYPE_DESTRUCTORS (type);
4644 return (dtor && DECL_VIRTUAL_P (dtor));
4647 /* Returns true iff class T has a move constructor. */
4650 type_has_move_constructor (tree t)
4654 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4656 gcc_assert (COMPLETE_TYPE_P (t));
4657 lazily_declare_fn (sfk_move_constructor, t);
4660 if (!CLASSTYPE_METHOD_VEC (t))
4663 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4664 if (move_fn_p (OVL_CURRENT (fns)))
4670 /* Returns true iff class T has a move assignment operator. */
4673 type_has_move_assign (tree t)
4677 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4679 gcc_assert (COMPLETE_TYPE_P (t));
4680 lazily_declare_fn (sfk_move_assignment, t);
4683 for (fns = lookup_fnfields_slot_nolazy (t, ansi_assopname (NOP_EXPR));
4684 fns; fns = OVL_NEXT (fns))
4685 if (move_fn_p (OVL_CURRENT (fns)))
4691 /* Returns true iff class T has a move constructor that was explicitly
4692 declared in the class body. Note that this is different from
4693 "user-provided", which doesn't include functions that are defaulted in
4697 type_has_user_declared_move_constructor (tree t)
4701 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4704 if (!CLASSTYPE_METHOD_VEC (t))
4707 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4709 tree fn = OVL_CURRENT (fns);
4710 if (move_fn_p (fn) && !DECL_ARTIFICIAL (fn))
4717 /* Returns true iff class T has a move assignment operator that was
4718 explicitly declared in the class body. */
4721 type_has_user_declared_move_assign (tree t)
4725 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4728 for (fns = lookup_fnfields_slot_nolazy (t, ansi_assopname (NOP_EXPR));
4729 fns; fns = OVL_NEXT (fns))
4731 tree fn = OVL_CURRENT (fns);
4732 if (move_fn_p (fn) && !DECL_ARTIFICIAL (fn))
4739 /* Nonzero if we need to build up a constructor call when initializing an
4740 object of this class, either because it has a user-provided constructor
4741 or because it doesn't have a default constructor (so we need to give an
4742 error if no initializer is provided). Use TYPE_NEEDS_CONSTRUCTING when
4743 what you care about is whether or not an object can be produced by a
4744 constructor (e.g. so we don't set TREE_READONLY on const variables of
4745 such type); use this function when what you care about is whether or not
4746 to try to call a constructor to create an object. The latter case is
4747 the former plus some cases of constructors that cannot be called. */
4750 type_build_ctor_call (tree t)
4753 if (TYPE_NEEDS_CONSTRUCTING (t))
4755 inner = strip_array_types (t);
4756 return (CLASS_TYPE_P (inner) && !TYPE_HAS_DEFAULT_CONSTRUCTOR (inner)
4757 && !ANON_AGGR_TYPE_P (inner));
4760 /* Remove all zero-width bit-fields from T. */
4763 remove_zero_width_bit_fields (tree t)
4767 fieldsp = &TYPE_FIELDS (t);
4770 if (TREE_CODE (*fieldsp) == FIELD_DECL
4771 && DECL_C_BIT_FIELD (*fieldsp)
4772 /* We should not be confused by the fact that grokbitfield
4773 temporarily sets the width of the bit field into
4774 DECL_INITIAL (*fieldsp).
4775 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4777 && integer_zerop (DECL_SIZE (*fieldsp)))
4778 *fieldsp = DECL_CHAIN (*fieldsp);
4780 fieldsp = &DECL_CHAIN (*fieldsp);
4784 /* Returns TRUE iff we need a cookie when dynamically allocating an
4785 array whose elements have the indicated class TYPE. */
4788 type_requires_array_cookie (tree type)
4791 bool has_two_argument_delete_p = false;
4793 gcc_assert (CLASS_TYPE_P (type));
4795 /* If there's a non-trivial destructor, we need a cookie. In order
4796 to iterate through the array calling the destructor for each
4797 element, we'll have to know how many elements there are. */
4798 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4801 /* If the usual deallocation function is a two-argument whose second
4802 argument is of type `size_t', then we have to pass the size of
4803 the array to the deallocation function, so we will need to store
4805 fns = lookup_fnfields (TYPE_BINFO (type),
4806 ansi_opname (VEC_DELETE_EXPR),
4808 /* If there are no `operator []' members, or the lookup is
4809 ambiguous, then we don't need a cookie. */
4810 if (!fns || fns == error_mark_node)
4812 /* Loop through all of the functions. */
4813 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4818 /* Select the current function. */
4819 fn = OVL_CURRENT (fns);
4820 /* See if this function is a one-argument delete function. If
4821 it is, then it will be the usual deallocation function. */
4822 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4823 if (second_parm == void_list_node)
4825 /* Do not consider this function if its second argument is an
4829 /* Otherwise, if we have a two-argument function and the second
4830 argument is `size_t', it will be the usual deallocation
4831 function -- unless there is one-argument function, too. */
4832 if (TREE_CHAIN (second_parm) == void_list_node
4833 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4834 has_two_argument_delete_p = true;
4837 return has_two_argument_delete_p;
4840 /* Finish computing the `literal type' property of class type T.
4842 At this point, we have already processed base classes and
4843 non-static data members. We need to check whether the copy
4844 constructor is trivial, the destructor is trivial, and there
4845 is a trivial default constructor or at least one constexpr
4846 constructor other than the copy constructor. */
4849 finalize_literal_type_property (tree t)
4853 if (cxx_dialect < cxx0x
4854 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
4855 CLASSTYPE_LITERAL_P (t) = false;
4856 else if (CLASSTYPE_LITERAL_P (t) && !TYPE_HAS_TRIVIAL_DFLT (t)
4857 && CLASSTYPE_NON_AGGREGATE (t)
4858 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4859 CLASSTYPE_LITERAL_P (t) = false;
4861 if (!CLASSTYPE_LITERAL_P (t))
4862 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4863 if (DECL_DECLARED_CONSTEXPR_P (fn)
4864 && TREE_CODE (fn) != TEMPLATE_DECL
4865 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
4866 && !DECL_CONSTRUCTOR_P (fn))
4868 DECL_DECLARED_CONSTEXPR_P (fn) = false;
4869 if (!DECL_GENERATED_P (fn))
4871 error ("enclosing class of constexpr non-static member "
4872 "function %q+#D is not a literal type", fn);
4873 explain_non_literal_class (t);
4878 /* T is a non-literal type used in a context which requires a constant
4879 expression. Explain why it isn't literal. */
4882 explain_non_literal_class (tree t)
4884 static struct pointer_set_t *diagnosed;
4886 if (!CLASS_TYPE_P (t))
4888 t = TYPE_MAIN_VARIANT (t);
4890 if (diagnosed == NULL)
4891 diagnosed = pointer_set_create ();
4892 if (pointer_set_insert (diagnosed, t) != 0)
4893 /* Already explained. */
4896 inform (0, "%q+T is not literal because:", t);
4897 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
4898 inform (0, " %q+T has a non-trivial destructor", t);
4899 else if (CLASSTYPE_NON_AGGREGATE (t)
4900 && !TYPE_HAS_TRIVIAL_DFLT (t)
4901 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4903 inform (0, " %q+T is not an aggregate, does not have a trivial "
4904 "default constructor, and has no constexpr constructor that "
4905 "is not a copy or move constructor", t);
4906 if (TYPE_HAS_DEFAULT_CONSTRUCTOR (t)
4907 && !type_has_user_provided_default_constructor (t))
4908 explain_invalid_constexpr_fn (locate_ctor (t));
4912 tree binfo, base_binfo, field; int i;
4913 for (binfo = TYPE_BINFO (t), i = 0;
4914 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
4916 tree basetype = TREE_TYPE (base_binfo);
4917 if (!CLASSTYPE_LITERAL_P (basetype))
4919 inform (0, " base class %qT of %q+T is non-literal",
4921 explain_non_literal_class (basetype);
4925 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4928 if (TREE_CODE (field) != FIELD_DECL)
4930 ftype = TREE_TYPE (field);
4931 if (!literal_type_p (ftype))
4933 inform (0, " non-static data member %q+D has "
4934 "non-literal type", field);
4935 if (CLASS_TYPE_P (ftype))
4936 explain_non_literal_class (ftype);
4942 /* Check the validity of the bases and members declared in T. Add any
4943 implicitly-generated functions (like copy-constructors and
4944 assignment operators). Compute various flag bits (like
4945 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4946 level: i.e., independently of the ABI in use. */
4949 check_bases_and_members (tree t)
4951 /* Nonzero if the implicitly generated copy constructor should take
4952 a non-const reference argument. */
4953 int cant_have_const_ctor;
4954 /* Nonzero if the implicitly generated assignment operator
4955 should take a non-const reference argument. */
4956 int no_const_asn_ref;
4958 bool saved_complex_asn_ref;
4959 bool saved_nontrivial_dtor;
4962 /* By default, we use const reference arguments and generate default
4964 cant_have_const_ctor = 0;
4965 no_const_asn_ref = 0;
4967 /* Check all the base-classes. */
4968 check_bases (t, &cant_have_const_ctor,
4971 /* Check all the method declarations. */
4974 /* Save the initial values of these flags which only indicate whether
4975 or not the class has user-provided functions. As we analyze the
4976 bases and members we can set these flags for other reasons. */
4977 saved_complex_asn_ref = TYPE_HAS_COMPLEX_COPY_ASSIGN (t);
4978 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4980 /* Check all the data member declarations. We cannot call
4981 check_field_decls until we have called check_bases check_methods,
4982 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4983 being set appropriately. */
4984 check_field_decls (t, &access_decls,
4985 &cant_have_const_ctor,
4988 /* A nearly-empty class has to be vptr-containing; a nearly empty
4989 class contains just a vptr. */
4990 if (!TYPE_CONTAINS_VPTR_P (t))
4991 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4993 /* Do some bookkeeping that will guide the generation of implicitly
4994 declared member functions. */
4995 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4996 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4997 /* We need to call a constructor for this class if it has a
4998 user-provided constructor, or if the default constructor is going
4999 to initialize the vptr. (This is not an if-and-only-if;
5000 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
5001 themselves need constructing.) */
5002 TYPE_NEEDS_CONSTRUCTING (t)
5003 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
5006 An aggregate is an array or a class with no user-provided
5007 constructors ... and no virtual functions.
5009 Again, other conditions for being an aggregate are checked
5011 CLASSTYPE_NON_AGGREGATE (t)
5012 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
5013 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
5014 retain the old definition internally for ABI reasons. */
5015 CLASSTYPE_NON_LAYOUT_POD_P (t)
5016 |= (CLASSTYPE_NON_AGGREGATE (t)
5017 || saved_nontrivial_dtor || saved_complex_asn_ref);
5018 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
5019 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
5020 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
5021 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
5023 /* If the class has no user-declared constructor, but does have
5024 non-static const or reference data members that can never be
5025 initialized, issue a warning. */
5026 if (warn_uninitialized
5027 /* Classes with user-declared constructors are presumed to
5028 initialize these members. */
5029 && !TYPE_HAS_USER_CONSTRUCTOR (t)
5030 /* Aggregates can be initialized with brace-enclosed
5032 && CLASSTYPE_NON_AGGREGATE (t))
5036 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5040 if (TREE_CODE (field) != FIELD_DECL)
5043 type = TREE_TYPE (field);
5044 if (TREE_CODE (type) == REFERENCE_TYPE)
5045 warning (OPT_Wuninitialized, "non-static reference %q+#D "
5046 "in class without a constructor", field);
5047 else if (CP_TYPE_CONST_P (type)
5048 && (!CLASS_TYPE_P (type)
5049 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
5050 warning (OPT_Wuninitialized, "non-static const member %q+#D "
5051 "in class without a constructor", field);
5055 /* Synthesize any needed methods. */
5056 add_implicitly_declared_members (t,
5057 cant_have_const_ctor,
5060 /* Check defaulted declarations here so we have cant_have_const_ctor
5061 and don't need to worry about clones. */
5062 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
5063 if (DECL_DEFAULTED_IN_CLASS_P (fn))
5065 int copy = copy_fn_p (fn);
5069 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
5070 : !no_const_asn_ref);
5071 bool fn_const_p = (copy == 2);
5073 if (fn_const_p && !imp_const_p)
5074 /* If the function is defaulted outside the class, we just
5075 give the synthesis error. */
5076 error ("%q+D declared to take const reference, but implicit "
5077 "declaration would take non-const", fn);
5078 else if (imp_const_p && !fn_const_p)
5079 error ("%q+D declared to take non-const reference cannot be "
5080 "defaulted in the class body", fn);
5082 defaulted_late_check (fn);
5085 if (LAMBDA_TYPE_P (t))
5087 /* "The closure type associated with a lambda-expression has a deleted
5088 default constructor and a deleted copy assignment operator." */
5089 TYPE_NEEDS_CONSTRUCTING (t) = 1;
5090 TYPE_HAS_COMPLEX_DFLT (t) = 1;
5091 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
5092 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 0;
5094 /* "This class type is not an aggregate." */
5095 CLASSTYPE_NON_AGGREGATE (t) = 1;
5098 /* Compute the 'literal type' property before we
5099 do anything with non-static member functions. */
5100 finalize_literal_type_property (t);
5102 /* Create the in-charge and not-in-charge variants of constructors
5104 clone_constructors_and_destructors (t);
5106 /* Process the using-declarations. */
5107 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
5108 handle_using_decl (TREE_VALUE (access_decls), t);
5110 /* Build and sort the CLASSTYPE_METHOD_VEC. */
5111 finish_struct_methods (t);
5113 /* Figure out whether or not we will need a cookie when dynamically
5114 allocating an array of this type. */
5115 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
5116 = type_requires_array_cookie (t);
5119 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
5120 accordingly. If a new vfield was created (because T doesn't have a
5121 primary base class), then the newly created field is returned. It
5122 is not added to the TYPE_FIELDS list; it is the caller's
5123 responsibility to do that. Accumulate declared virtual functions
5127 create_vtable_ptr (tree t, tree* virtuals_p)
5131 /* Collect the virtual functions declared in T. */
5132 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
5133 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
5134 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
5136 tree new_virtual = make_node (TREE_LIST);
5138 BV_FN (new_virtual) = fn;
5139 BV_DELTA (new_virtual) = integer_zero_node;
5140 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
5142 TREE_CHAIN (new_virtual) = *virtuals_p;
5143 *virtuals_p = new_virtual;
5146 /* If we couldn't find an appropriate base class, create a new field
5147 here. Even if there weren't any new virtual functions, we might need a
5148 new virtual function table if we're supposed to include vptrs in
5149 all classes that need them. */
5150 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
5152 /* We build this decl with vtbl_ptr_type_node, which is a
5153 `vtable_entry_type*'. It might seem more precise to use
5154 `vtable_entry_type (*)[N]' where N is the number of virtual
5155 functions. However, that would require the vtable pointer in
5156 base classes to have a different type than the vtable pointer
5157 in derived classes. We could make that happen, but that
5158 still wouldn't solve all the problems. In particular, the
5159 type-based alias analysis code would decide that assignments
5160 to the base class vtable pointer can't alias assignments to
5161 the derived class vtable pointer, since they have different
5162 types. Thus, in a derived class destructor, where the base
5163 class constructor was inlined, we could generate bad code for
5164 setting up the vtable pointer.
5166 Therefore, we use one type for all vtable pointers. We still
5167 use a type-correct type; it's just doesn't indicate the array
5168 bounds. That's better than using `void*' or some such; it's
5169 cleaner, and it let's the alias analysis code know that these
5170 stores cannot alias stores to void*! */
5173 field = build_decl (input_location,
5174 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
5175 DECL_VIRTUAL_P (field) = 1;
5176 DECL_ARTIFICIAL (field) = 1;
5177 DECL_FIELD_CONTEXT (field) = t;
5178 DECL_FCONTEXT (field) = t;
5179 if (TYPE_PACKED (t))
5180 DECL_PACKED (field) = 1;
5182 TYPE_VFIELD (t) = field;
5184 /* This class is non-empty. */
5185 CLASSTYPE_EMPTY_P (t) = 0;
5193 /* Add OFFSET to all base types of BINFO which is a base in the
5194 hierarchy dominated by T.
5196 OFFSET, which is a type offset, is number of bytes. */
5199 propagate_binfo_offsets (tree binfo, tree offset)
5205 /* Update BINFO's offset. */
5206 BINFO_OFFSET (binfo)
5207 = convert (sizetype,
5208 size_binop (PLUS_EXPR,
5209 convert (ssizetype, BINFO_OFFSET (binfo)),
5212 /* Find the primary base class. */
5213 primary_binfo = get_primary_binfo (binfo);
5215 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
5216 propagate_binfo_offsets (primary_binfo, offset);
5218 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
5220 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5222 /* Don't do the primary base twice. */
5223 if (base_binfo == primary_binfo)
5226 if (BINFO_VIRTUAL_P (base_binfo))
5229 propagate_binfo_offsets (base_binfo, offset);
5233 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
5234 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
5235 empty subobjects of T. */
5238 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
5242 bool first_vbase = true;
5245 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
5248 if (!abi_version_at_least(2))
5250 /* In G++ 3.2, we incorrectly rounded the size before laying out
5251 the virtual bases. */
5252 finish_record_layout (rli, /*free_p=*/false);
5253 #ifdef STRUCTURE_SIZE_BOUNDARY
5254 /* Packed structures don't need to have minimum size. */
5255 if (! TYPE_PACKED (t))
5256 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
5258 rli->offset = TYPE_SIZE_UNIT (t);
5259 rli->bitpos = bitsize_zero_node;
5260 rli->record_align = TYPE_ALIGN (t);
5263 /* Find the last field. The artificial fields created for virtual
5264 bases will go after the last extant field to date. */
5265 next_field = &TYPE_FIELDS (t);
5267 next_field = &DECL_CHAIN (*next_field);
5269 /* Go through the virtual bases, allocating space for each virtual
5270 base that is not already a primary base class. These are
5271 allocated in inheritance graph order. */
5272 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
5274 if (!BINFO_VIRTUAL_P (vbase))
5277 if (!BINFO_PRIMARY_P (vbase))
5279 tree basetype = TREE_TYPE (vbase);
5281 /* This virtual base is not a primary base of any class in the
5282 hierarchy, so we have to add space for it. */
5283 next_field = build_base_field (rli, vbase,
5284 offsets, next_field);
5286 /* If the first virtual base might have been placed at a
5287 lower address, had we started from CLASSTYPE_SIZE, rather
5288 than TYPE_SIZE, issue a warning. There can be both false
5289 positives and false negatives from this warning in rare
5290 cases; to deal with all the possibilities would probably
5291 require performing both layout algorithms and comparing
5292 the results which is not particularly tractable. */
5296 (size_binop (CEIL_DIV_EXPR,
5297 round_up_loc (input_location,
5299 CLASSTYPE_ALIGN (basetype)),
5301 BINFO_OFFSET (vbase))))
5303 "offset of virtual base %qT is not ABI-compliant and "
5304 "may change in a future version of GCC",
5307 first_vbase = false;
5312 /* Returns the offset of the byte just past the end of the base class
5316 end_of_base (tree binfo)
5320 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
5321 size = TYPE_SIZE_UNIT (char_type_node);
5322 else if (is_empty_class (BINFO_TYPE (binfo)))
5323 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
5324 allocate some space for it. It cannot have virtual bases, so
5325 TYPE_SIZE_UNIT is fine. */
5326 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5328 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5330 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
5333 /* Returns the offset of the byte just past the end of the base class
5334 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
5335 only non-virtual bases are included. */
5338 end_of_class (tree t, int include_virtuals_p)
5340 tree result = size_zero_node;
5341 VEC(tree,gc) *vbases;
5347 for (binfo = TYPE_BINFO (t), i = 0;
5348 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5350 if (!include_virtuals_p
5351 && BINFO_VIRTUAL_P (base_binfo)
5352 && (!BINFO_PRIMARY_P (base_binfo)
5353 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
5356 offset = end_of_base (base_binfo);
5357 if (INT_CST_LT_UNSIGNED (result, offset))
5361 /* G++ 3.2 did not check indirect virtual bases. */
5362 if (abi_version_at_least (2) && include_virtuals_p)
5363 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5364 VEC_iterate (tree, vbases, i, base_binfo); i++)
5366 offset = end_of_base (base_binfo);
5367 if (INT_CST_LT_UNSIGNED (result, offset))
5374 /* Warn about bases of T that are inaccessible because they are
5375 ambiguous. For example:
5378 struct T : public S {};
5379 struct U : public S, public T {};
5381 Here, `(S*) new U' is not allowed because there are two `S'
5385 warn_about_ambiguous_bases (tree t)
5388 VEC(tree,gc) *vbases;
5393 /* If there are no repeated bases, nothing can be ambiguous. */
5394 if (!CLASSTYPE_REPEATED_BASE_P (t))
5397 /* Check direct bases. */
5398 for (binfo = TYPE_BINFO (t), i = 0;
5399 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5401 basetype = BINFO_TYPE (base_binfo);
5403 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5404 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
5408 /* Check for ambiguous virtual bases. */
5410 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5411 VEC_iterate (tree, vbases, i, binfo); i++)
5413 basetype = BINFO_TYPE (binfo);
5415 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5416 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
5421 /* Compare two INTEGER_CSTs K1 and K2. */
5424 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
5426 return tree_int_cst_compare ((tree) k1, (tree) k2);
5429 /* Increase the size indicated in RLI to account for empty classes
5430 that are "off the end" of the class. */
5433 include_empty_classes (record_layout_info rli)
5438 /* It might be the case that we grew the class to allocate a
5439 zero-sized base class. That won't be reflected in RLI, yet,
5440 because we are willing to overlay multiple bases at the same
5441 offset. However, now we need to make sure that RLI is big enough
5442 to reflect the entire class. */
5443 eoc = end_of_class (rli->t,
5444 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
5445 rli_size = rli_size_unit_so_far (rli);
5446 if (TREE_CODE (rli_size) == INTEGER_CST
5447 && INT_CST_LT_UNSIGNED (rli_size, eoc))
5449 if (!abi_version_at_least (2))
5450 /* In version 1 of the ABI, the size of a class that ends with
5451 a bitfield was not rounded up to a whole multiple of a
5452 byte. Because rli_size_unit_so_far returns only the number
5453 of fully allocated bytes, any extra bits were not included
5455 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
5457 /* The size should have been rounded to a whole byte. */
5458 gcc_assert (tree_int_cst_equal
5459 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
5461 = size_binop (PLUS_EXPR,
5463 size_binop (MULT_EXPR,
5464 convert (bitsizetype,
5465 size_binop (MINUS_EXPR,
5467 bitsize_int (BITS_PER_UNIT)));
5468 normalize_rli (rli);
5472 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
5473 BINFO_OFFSETs for all of the base-classes. Position the vtable
5474 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
5477 layout_class_type (tree t, tree *virtuals_p)
5479 tree non_static_data_members;
5482 record_layout_info rli;
5483 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
5484 types that appear at that offset. */
5485 splay_tree empty_base_offsets;
5486 /* True if the last field layed out was a bit-field. */
5487 bool last_field_was_bitfield = false;
5488 /* The location at which the next field should be inserted. */
5490 /* T, as a base class. */
5493 /* Keep track of the first non-static data member. */
5494 non_static_data_members = TYPE_FIELDS (t);
5496 /* Start laying out the record. */
5497 rli = start_record_layout (t);
5499 /* Mark all the primary bases in the hierarchy. */
5500 determine_primary_bases (t);
5502 /* Create a pointer to our virtual function table. */
5503 vptr = create_vtable_ptr (t, virtuals_p);
5505 /* The vptr is always the first thing in the class. */
5508 DECL_CHAIN (vptr) = TYPE_FIELDS (t);
5509 TYPE_FIELDS (t) = vptr;
5510 next_field = &DECL_CHAIN (vptr);
5511 place_field (rli, vptr);
5514 next_field = &TYPE_FIELDS (t);
5516 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5517 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
5519 build_base_fields (rli, empty_base_offsets, next_field);
5521 /* Layout the non-static data members. */
5522 for (field = non_static_data_members; field; field = DECL_CHAIN (field))
5527 /* We still pass things that aren't non-static data members to
5528 the back end, in case it wants to do something with them. */
5529 if (TREE_CODE (field) != FIELD_DECL)
5531 place_field (rli, field);
5532 /* If the static data member has incomplete type, keep track
5533 of it so that it can be completed later. (The handling
5534 of pending statics in finish_record_layout is
5535 insufficient; consider:
5538 struct S2 { static S1 s1; };
5540 At this point, finish_record_layout will be called, but
5541 S1 is still incomplete.) */
5542 if (TREE_CODE (field) == VAR_DECL)
5544 maybe_register_incomplete_var (field);
5545 /* The visibility of static data members is determined
5546 at their point of declaration, not their point of
5548 determine_visibility (field);
5553 type = TREE_TYPE (field);
5554 if (type == error_mark_node)
5557 padding = NULL_TREE;
5559 /* If this field is a bit-field whose width is greater than its
5560 type, then there are some special rules for allocating
5562 if (DECL_C_BIT_FIELD (field)
5563 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
5567 bool was_unnamed_p = false;
5568 /* We must allocate the bits as if suitably aligned for the
5569 longest integer type that fits in this many bits. type
5570 of the field. Then, we are supposed to use the left over
5571 bits as additional padding. */
5572 for (itk = itk_char; itk != itk_none; ++itk)
5573 if (integer_types[itk] != NULL_TREE
5574 && (INT_CST_LT (size_int (MAX_FIXED_MODE_SIZE),
5575 TYPE_SIZE (integer_types[itk]))
5576 || INT_CST_LT (DECL_SIZE (field),
5577 TYPE_SIZE (integer_types[itk]))))
5580 /* ITK now indicates a type that is too large for the
5581 field. We have to back up by one to find the largest
5586 integer_type = integer_types[itk];
5587 } while (itk > 0 && integer_type == NULL_TREE);
5589 /* Figure out how much additional padding is required. GCC
5590 3.2 always created a padding field, even if it had zero
5592 if (!abi_version_at_least (2)
5593 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
5595 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
5596 /* In a union, the padding field must have the full width
5597 of the bit-field; all fields start at offset zero. */
5598 padding = DECL_SIZE (field);
5601 if (TREE_CODE (t) == UNION_TYPE)
5602 warning (OPT_Wabi, "size assigned to %qT may not be "
5603 "ABI-compliant and may change in a future "
5606 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
5607 TYPE_SIZE (integer_type));
5610 #ifdef PCC_BITFIELD_TYPE_MATTERS
5611 /* An unnamed bitfield does not normally affect the
5612 alignment of the containing class on a target where
5613 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5614 make any exceptions for unnamed bitfields when the
5615 bitfields are longer than their types. Therefore, we
5616 temporarily give the field a name. */
5617 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
5619 was_unnamed_p = true;
5620 DECL_NAME (field) = make_anon_name ();
5623 DECL_SIZE (field) = TYPE_SIZE (integer_type);
5624 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
5625 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
5626 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5627 empty_base_offsets);
5629 DECL_NAME (field) = NULL_TREE;
5630 /* Now that layout has been performed, set the size of the
5631 field to the size of its declared type; the rest of the
5632 field is effectively invisible. */
5633 DECL_SIZE (field) = TYPE_SIZE (type);
5634 /* We must also reset the DECL_MODE of the field. */
5635 if (abi_version_at_least (2))
5636 DECL_MODE (field) = TYPE_MODE (type);
5638 && DECL_MODE (field) != TYPE_MODE (type))
5639 /* Versions of G++ before G++ 3.4 did not reset the
5642 "the offset of %qD may not be ABI-compliant and may "
5643 "change in a future version of GCC", field);
5646 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5647 empty_base_offsets);
5649 /* Remember the location of any empty classes in FIELD. */
5650 if (abi_version_at_least (2))
5651 record_subobject_offsets (TREE_TYPE (field),
5652 byte_position(field),
5654 /*is_data_member=*/true);
5656 /* If a bit-field does not immediately follow another bit-field,
5657 and yet it starts in the middle of a byte, we have failed to
5658 comply with the ABI. */
5660 && DECL_C_BIT_FIELD (field)
5661 /* The TREE_NO_WARNING flag gets set by Objective-C when
5662 laying out an Objective-C class. The ObjC ABI differs
5663 from the C++ ABI, and so we do not want a warning
5665 && !TREE_NO_WARNING (field)
5666 && !last_field_was_bitfield
5667 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5668 DECL_FIELD_BIT_OFFSET (field),
5669 bitsize_unit_node)))
5670 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5671 "change in a future version of GCC", field);
5673 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5674 offset of the field. */
5676 && !abi_version_at_least (2)
5677 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5678 byte_position (field))
5679 && contains_empty_class_p (TREE_TYPE (field)))
5680 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5681 "classes to be placed at different locations in a "
5682 "future version of GCC", field);
5684 /* The middle end uses the type of expressions to determine the
5685 possible range of expression values. In order to optimize
5686 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5687 must be made aware of the width of "i", via its type.
5689 Because C++ does not have integer types of arbitrary width,
5690 we must (for the purposes of the front end) convert from the
5691 type assigned here to the declared type of the bitfield
5692 whenever a bitfield expression is used as an rvalue.
5693 Similarly, when assigning a value to a bitfield, the value
5694 must be converted to the type given the bitfield here. */
5695 if (DECL_C_BIT_FIELD (field))
5697 unsigned HOST_WIDE_INT width;
5698 tree ftype = TREE_TYPE (field);
5699 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5700 if (width != TYPE_PRECISION (ftype))
5703 = c_build_bitfield_integer_type (width,
5704 TYPE_UNSIGNED (ftype));
5706 = cp_build_qualified_type (TREE_TYPE (field),
5707 cp_type_quals (ftype));
5711 /* If we needed additional padding after this field, add it
5717 padding_field = build_decl (input_location,
5721 DECL_BIT_FIELD (padding_field) = 1;
5722 DECL_SIZE (padding_field) = padding;
5723 DECL_CONTEXT (padding_field) = t;
5724 DECL_ARTIFICIAL (padding_field) = 1;
5725 DECL_IGNORED_P (padding_field) = 1;
5726 layout_nonempty_base_or_field (rli, padding_field,
5728 empty_base_offsets);
5731 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5734 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5736 /* Make sure that we are on a byte boundary so that the size of
5737 the class without virtual bases will always be a round number
5739 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5740 normalize_rli (rli);
5743 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5745 if (!abi_version_at_least (2))
5746 include_empty_classes(rli);
5748 /* Delete all zero-width bit-fields from the list of fields. Now
5749 that the type is laid out they are no longer important. */
5750 remove_zero_width_bit_fields (t);
5752 /* Create the version of T used for virtual bases. We do not use
5753 make_class_type for this version; this is an artificial type. For
5754 a POD type, we just reuse T. */
5755 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5757 base_t = make_node (TREE_CODE (t));
5759 /* Set the size and alignment for the new type. In G++ 3.2, all
5760 empty classes were considered to have size zero when used as
5762 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5764 TYPE_SIZE (base_t) = bitsize_zero_node;
5765 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5766 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5768 "layout of classes derived from empty class %qT "
5769 "may change in a future version of GCC",
5776 /* If the ABI version is not at least two, and the last
5777 field was a bit-field, RLI may not be on a byte
5778 boundary. In particular, rli_size_unit_so_far might
5779 indicate the last complete byte, while rli_size_so_far
5780 indicates the total number of bits used. Therefore,
5781 rli_size_so_far, rather than rli_size_unit_so_far, is
5782 used to compute TYPE_SIZE_UNIT. */
5783 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5784 TYPE_SIZE_UNIT (base_t)
5785 = size_binop (MAX_EXPR,
5787 size_binop (CEIL_DIV_EXPR,
5788 rli_size_so_far (rli),
5789 bitsize_int (BITS_PER_UNIT))),
5792 = size_binop (MAX_EXPR,
5793 rli_size_so_far (rli),
5794 size_binop (MULT_EXPR,
5795 convert (bitsizetype, eoc),
5796 bitsize_int (BITS_PER_UNIT)));
5798 TYPE_ALIGN (base_t) = rli->record_align;
5799 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5801 /* Copy the fields from T. */
5802 next_field = &TYPE_FIELDS (base_t);
5803 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5804 if (TREE_CODE (field) == FIELD_DECL)
5806 *next_field = build_decl (input_location,
5810 DECL_CONTEXT (*next_field) = base_t;
5811 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5812 DECL_FIELD_BIT_OFFSET (*next_field)
5813 = DECL_FIELD_BIT_OFFSET (field);
5814 DECL_SIZE (*next_field) = DECL_SIZE (field);
5815 DECL_MODE (*next_field) = DECL_MODE (field);
5816 next_field = &DECL_CHAIN (*next_field);
5819 /* Record the base version of the type. */
5820 CLASSTYPE_AS_BASE (t) = base_t;
5821 TYPE_CONTEXT (base_t) = t;
5824 CLASSTYPE_AS_BASE (t) = t;
5826 /* Every empty class contains an empty class. */
5827 if (CLASSTYPE_EMPTY_P (t))
5828 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5830 /* Set the TYPE_DECL for this type to contain the right
5831 value for DECL_OFFSET, so that we can use it as part
5832 of a COMPONENT_REF for multiple inheritance. */
5833 layout_decl (TYPE_MAIN_DECL (t), 0);
5835 /* Now fix up any virtual base class types that we left lying
5836 around. We must get these done before we try to lay out the
5837 virtual function table. As a side-effect, this will remove the
5838 base subobject fields. */
5839 layout_virtual_bases (rli, empty_base_offsets);
5841 /* Make sure that empty classes are reflected in RLI at this
5843 include_empty_classes(rli);
5845 /* Make sure not to create any structures with zero size. */
5846 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5848 build_decl (input_location,
5849 FIELD_DECL, NULL_TREE, char_type_node));
5851 /* If this is a non-POD, declaring it packed makes a difference to how it
5852 can be used as a field; don't let finalize_record_size undo it. */
5853 if (TYPE_PACKED (t) && !layout_pod_type_p (t))
5854 rli->packed_maybe_necessary = true;
5856 /* Let the back end lay out the type. */
5857 finish_record_layout (rli, /*free_p=*/true);
5859 /* Warn about bases that can't be talked about due to ambiguity. */
5860 warn_about_ambiguous_bases (t);
5862 /* Now that we're done with layout, give the base fields the real types. */
5863 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5864 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5865 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5868 splay_tree_delete (empty_base_offsets);
5870 if (CLASSTYPE_EMPTY_P (t)
5871 && tree_int_cst_lt (sizeof_biggest_empty_class,
5872 TYPE_SIZE_UNIT (t)))
5873 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5876 /* Determine the "key method" for the class type indicated by TYPE,
5877 and set CLASSTYPE_KEY_METHOD accordingly. */
5880 determine_key_method (tree type)
5884 if (TYPE_FOR_JAVA (type)
5885 || processing_template_decl
5886 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5887 || CLASSTYPE_INTERFACE_KNOWN (type))
5890 /* The key method is the first non-pure virtual function that is not
5891 inline at the point of class definition. On some targets the
5892 key function may not be inline; those targets should not call
5893 this function until the end of the translation unit. */
5894 for (method = TYPE_METHODS (type); method != NULL_TREE;
5895 method = DECL_CHAIN (method))
5896 if (DECL_VINDEX (method) != NULL_TREE
5897 && ! DECL_DECLARED_INLINE_P (method)
5898 && ! DECL_PURE_VIRTUAL_P (method))
5900 CLASSTYPE_KEY_METHOD (type) = method;
5908 /* Allocate and return an instance of struct sorted_fields_type with
5911 static struct sorted_fields_type *
5912 sorted_fields_type_new (int n)
5914 struct sorted_fields_type *sft;
5915 sft = ggc_alloc_sorted_fields_type (sizeof (struct sorted_fields_type)
5916 + n * sizeof (tree));
5923 /* Perform processing required when the definition of T (a class type)
5927 finish_struct_1 (tree t)
5930 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5931 tree virtuals = NULL_TREE;
5934 if (COMPLETE_TYPE_P (t))
5936 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5937 error ("redefinition of %q#T", t);
5942 /* If this type was previously laid out as a forward reference,
5943 make sure we lay it out again. */
5944 TYPE_SIZE (t) = NULL_TREE;
5945 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5947 /* Make assumptions about the class; we'll reset the flags if
5949 CLASSTYPE_EMPTY_P (t) = 1;
5950 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5951 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5952 CLASSTYPE_LITERAL_P (t) = true;
5954 /* Do end-of-class semantic processing: checking the validity of the
5955 bases and members and add implicitly generated methods. */
5956 check_bases_and_members (t);
5958 /* Find the key method. */
5959 if (TYPE_CONTAINS_VPTR_P (t))
5961 /* The Itanium C++ ABI permits the key method to be chosen when
5962 the class is defined -- even though the key method so
5963 selected may later turn out to be an inline function. On
5964 some systems (such as ARM Symbian OS) the key method cannot
5965 be determined until the end of the translation unit. On such
5966 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5967 will cause the class to be added to KEYED_CLASSES. Then, in
5968 finish_file we will determine the key method. */
5969 if (targetm.cxx.key_method_may_be_inline ())
5970 determine_key_method (t);
5972 /* If a polymorphic class has no key method, we may emit the vtable
5973 in every translation unit where the class definition appears. */
5974 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5975 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5978 /* Layout the class itself. */
5979 layout_class_type (t, &virtuals);
5980 if (CLASSTYPE_AS_BASE (t) != t)
5981 /* We use the base type for trivial assignments, and hence it
5983 compute_record_mode (CLASSTYPE_AS_BASE (t));
5985 virtuals = modify_all_vtables (t, nreverse (virtuals));
5987 /* If necessary, create the primary vtable for this class. */
5988 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5990 /* We must enter these virtuals into the table. */
5991 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5992 build_primary_vtable (NULL_TREE, t);
5993 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5994 /* Here we know enough to change the type of our virtual
5995 function table, but we will wait until later this function. */
5996 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5999 if (TYPE_CONTAINS_VPTR_P (t))
6004 if (BINFO_VTABLE (TYPE_BINFO (t)))
6005 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
6006 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
6007 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
6009 /* Add entries for virtual functions introduced by this class. */
6010 BINFO_VIRTUALS (TYPE_BINFO (t))
6011 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
6013 /* Set DECL_VINDEX for all functions declared in this class. */
6014 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
6016 fn = TREE_CHAIN (fn),
6017 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
6018 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
6020 tree fndecl = BV_FN (fn);
6022 if (DECL_THUNK_P (fndecl))
6023 /* A thunk. We should never be calling this entry directly
6024 from this vtable -- we'd use the entry for the non
6025 thunk base function. */
6026 DECL_VINDEX (fndecl) = NULL_TREE;
6027 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
6028 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
6032 finish_struct_bits (t);
6033 set_method_tm_attributes (t);
6035 /* Complete the rtl for any static member objects of the type we're
6037 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
6038 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
6039 && TREE_TYPE (x) != error_mark_node
6040 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
6041 DECL_MODE (x) = TYPE_MODE (t);
6043 /* Done with FIELDS...now decide whether to sort these for
6044 faster lookups later.
6046 We use a small number because most searches fail (succeeding
6047 ultimately as the search bores through the inheritance
6048 hierarchy), and we want this failure to occur quickly. */
6050 n_fields = count_fields (TYPE_FIELDS (t));
6053 struct sorted_fields_type *field_vec = sorted_fields_type_new (n_fields);
6054 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
6055 qsort (field_vec->elts, n_fields, sizeof (tree),
6057 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
6060 /* Complain if one of the field types requires lower visibility. */
6061 constrain_class_visibility (t);
6063 /* Make the rtl for any new vtables we have created, and unmark
6064 the base types we marked. */
6067 /* Build the VTT for T. */
6070 /* This warning does not make sense for Java classes, since they
6071 cannot have destructors. */
6072 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
6076 dtor = CLASSTYPE_DESTRUCTORS (t);
6077 if (/* An implicitly declared destructor is always public. And,
6078 if it were virtual, we would have created it by now. */
6080 || (!DECL_VINDEX (dtor)
6081 && (/* public non-virtual */
6082 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
6083 || (/* non-public non-virtual with friends */
6084 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
6085 && (CLASSTYPE_FRIEND_CLASSES (t)
6086 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
6087 warning (OPT_Wnon_virtual_dtor,
6088 "%q#T has virtual functions and accessible"
6089 " non-virtual destructor", t);
6094 if (warn_overloaded_virtual)
6097 /* Class layout, assignment of virtual table slots, etc., is now
6098 complete. Give the back end a chance to tweak the visibility of
6099 the class or perform any other required target modifications. */
6100 targetm.cxx.adjust_class_at_definition (t);
6102 maybe_suppress_debug_info (t);
6104 dump_class_hierarchy (t);
6106 /* Finish debugging output for this type. */
6107 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
6109 if (TYPE_TRANSPARENT_AGGR (t))
6111 tree field = first_field (t);
6112 if (field == NULL_TREE || error_operand_p (field))
6114 error ("type transparent class %qT does not have any fields", t);
6115 TYPE_TRANSPARENT_AGGR (t) = 0;
6117 else if (DECL_ARTIFICIAL (field))
6119 if (DECL_FIELD_IS_BASE (field))
6120 error ("type transparent class %qT has base classes", t);
6123 gcc_checking_assert (DECL_VIRTUAL_P (field));
6124 error ("type transparent class %qT has virtual functions", t);
6126 TYPE_TRANSPARENT_AGGR (t) = 0;
6131 /* When T was built up, the member declarations were added in reverse
6132 order. Rearrange them to declaration order. */
6135 unreverse_member_declarations (tree t)
6141 /* The following lists are all in reverse order. Put them in
6142 declaration order now. */
6143 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
6144 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
6146 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
6147 reverse order, so we can't just use nreverse. */
6149 for (x = TYPE_FIELDS (t);
6150 x && TREE_CODE (x) != TYPE_DECL;
6153 next = DECL_CHAIN (x);
6154 DECL_CHAIN (x) = prev;
6159 DECL_CHAIN (TYPE_FIELDS (t)) = x;
6161 TYPE_FIELDS (t) = prev;
6166 finish_struct (tree t, tree attributes)
6168 location_t saved_loc = input_location;
6170 /* Now that we've got all the field declarations, reverse everything
6172 unreverse_member_declarations (t);
6174 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
6176 /* Nadger the current location so that diagnostics point to the start of
6177 the struct, not the end. */
6178 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
6180 if (processing_template_decl)
6184 finish_struct_methods (t);
6185 TYPE_SIZE (t) = bitsize_zero_node;
6186 TYPE_SIZE_UNIT (t) = size_zero_node;
6188 /* We need to emit an error message if this type was used as a parameter
6189 and it is an abstract type, even if it is a template. We construct
6190 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
6191 account and we call complete_vars with this type, which will check
6192 the PARM_DECLS. Note that while the type is being defined,
6193 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
6194 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
6195 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
6196 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
6197 if (DECL_PURE_VIRTUAL_P (x))
6198 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
6200 /* We need to add the target functions to the CLASSTYPE_METHOD_VEC if
6201 an enclosing scope is a template class, so that this function be
6202 found by lookup_fnfields_1 when the using declaration is not
6203 instantiated yet. */
6204 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
6205 if (TREE_CODE (x) == USING_DECL)
6207 tree fn = strip_using_decl (x);
6208 if (is_overloaded_fn (fn))
6209 for (; fn; fn = OVL_NEXT (fn))
6210 add_method (t, OVL_CURRENT (fn), x);
6213 /* Remember current #pragma pack value. */
6214 TYPE_PRECISION (t) = maximum_field_alignment;
6217 finish_struct_1 (t);
6219 input_location = saved_loc;
6221 TYPE_BEING_DEFINED (t) = 0;
6223 if (current_class_type)
6226 error ("trying to finish struct, but kicked out due to previous parse errors");
6228 if (processing_template_decl && at_function_scope_p ())
6229 add_stmt (build_min (TAG_DEFN, t));
6234 /* Return the dynamic type of INSTANCE, if known.
6235 Used to determine whether the virtual function table is needed
6238 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6239 of our knowledge of its type. *NONNULL should be initialized
6240 before this function is called. */
6243 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
6245 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
6247 switch (TREE_CODE (instance))
6250 if (POINTER_TYPE_P (TREE_TYPE (instance)))
6253 return RECUR (TREE_OPERAND (instance, 0));
6256 /* This is a call to a constructor, hence it's never zero. */
6257 if (TREE_HAS_CONSTRUCTOR (instance))
6261 return TREE_TYPE (instance);
6266 /* This is a call to a constructor, hence it's never zero. */
6267 if (TREE_HAS_CONSTRUCTOR (instance))
6271 return TREE_TYPE (instance);
6273 return RECUR (TREE_OPERAND (instance, 0));
6275 case POINTER_PLUS_EXPR:
6278 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
6279 return RECUR (TREE_OPERAND (instance, 0));
6280 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
6281 /* Propagate nonnull. */
6282 return RECUR (TREE_OPERAND (instance, 0));
6287 return RECUR (TREE_OPERAND (instance, 0));
6290 instance = TREE_OPERAND (instance, 0);
6293 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
6294 with a real object -- given &p->f, p can still be null. */
6295 tree t = get_base_address (instance);
6296 /* ??? Probably should check DECL_WEAK here. */
6297 if (t && DECL_P (t))
6300 return RECUR (instance);
6303 /* If this component is really a base class reference, then the field
6304 itself isn't definitive. */
6305 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
6306 return RECUR (TREE_OPERAND (instance, 0));
6307 return RECUR (TREE_OPERAND (instance, 1));
6311 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
6312 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
6316 return TREE_TYPE (TREE_TYPE (instance));
6318 /* fall through... */
6322 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
6326 return TREE_TYPE (instance);
6328 else if (instance == current_class_ptr)
6333 /* if we're in a ctor or dtor, we know our type. If
6334 current_class_ptr is set but we aren't in a function, we're in
6335 an NSDMI (and therefore a constructor). */
6336 if (current_scope () != current_function_decl
6337 || (DECL_LANG_SPECIFIC (current_function_decl)
6338 && (DECL_CONSTRUCTOR_P (current_function_decl)
6339 || DECL_DESTRUCTOR_P (current_function_decl))))
6343 return TREE_TYPE (TREE_TYPE (instance));
6346 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
6348 /* We only need one hash table because it is always left empty. */
6351 ht = htab_create (37,
6356 /* Reference variables should be references to objects. */
6360 /* Enter the INSTANCE in a table to prevent recursion; a
6361 variable's initializer may refer to the variable
6363 if (TREE_CODE (instance) == VAR_DECL
6364 && DECL_INITIAL (instance)
6365 && !type_dependent_expression_p_push (DECL_INITIAL (instance))
6366 && !htab_find (ht, instance))
6371 slot = htab_find_slot (ht, instance, INSERT);
6373 type = RECUR (DECL_INITIAL (instance));
6374 htab_remove_elt (ht, instance);
6387 /* Return nonzero if the dynamic type of INSTANCE is known, and
6388 equivalent to the static type. We also handle the case where
6389 INSTANCE is really a pointer. Return negative if this is a
6390 ctor/dtor. There the dynamic type is known, but this might not be
6391 the most derived base of the original object, and hence virtual
6392 bases may not be layed out according to this type.
6394 Used to determine whether the virtual function table is needed
6397 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6398 of our knowledge of its type. *NONNULL should be initialized
6399 before this function is called. */
6402 resolves_to_fixed_type_p (tree instance, int* nonnull)
6404 tree t = TREE_TYPE (instance);
6408 if (processing_template_decl)
6410 /* In a template we only care about the type of the result. */
6416 fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
6417 if (fixed == NULL_TREE)
6419 if (POINTER_TYPE_P (t))
6421 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
6423 return cdtorp ? -1 : 1;
6428 init_class_processing (void)
6430 current_class_depth = 0;
6431 current_class_stack_size = 10;
6433 = XNEWVEC (struct class_stack_node, current_class_stack_size);
6434 local_classes = VEC_alloc (tree, gc, 8);
6435 sizeof_biggest_empty_class = size_zero_node;
6437 ridpointers[(int) RID_PUBLIC] = access_public_node;
6438 ridpointers[(int) RID_PRIVATE] = access_private_node;
6439 ridpointers[(int) RID_PROTECTED] = access_protected_node;
6442 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
6445 restore_class_cache (void)
6449 /* We are re-entering the same class we just left, so we don't
6450 have to search the whole inheritance matrix to find all the
6451 decls to bind again. Instead, we install the cached
6452 class_shadowed list and walk through it binding names. */
6453 push_binding_level (previous_class_level);
6454 class_binding_level = previous_class_level;
6455 /* Restore IDENTIFIER_TYPE_VALUE. */
6456 for (type = class_binding_level->type_shadowed;
6458 type = TREE_CHAIN (type))
6459 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
6462 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
6463 appropriate for TYPE.
6465 So that we may avoid calls to lookup_name, we cache the _TYPE
6466 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
6468 For multiple inheritance, we perform a two-pass depth-first search
6469 of the type lattice. */
6472 pushclass (tree type)
6474 class_stack_node_t csn;
6476 type = TYPE_MAIN_VARIANT (type);
6478 /* Make sure there is enough room for the new entry on the stack. */
6479 if (current_class_depth + 1 >= current_class_stack_size)
6481 current_class_stack_size *= 2;
6483 = XRESIZEVEC (struct class_stack_node, current_class_stack,
6484 current_class_stack_size);
6487 /* Insert a new entry on the class stack. */
6488 csn = current_class_stack + current_class_depth;
6489 csn->name = current_class_name;
6490 csn->type = current_class_type;
6491 csn->access = current_access_specifier;
6492 csn->names_used = 0;
6494 current_class_depth++;
6496 /* Now set up the new type. */
6497 current_class_name = TYPE_NAME (type);
6498 if (TREE_CODE (current_class_name) == TYPE_DECL)
6499 current_class_name = DECL_NAME (current_class_name);
6500 current_class_type = type;
6502 /* By default, things in classes are private, while things in
6503 structures or unions are public. */
6504 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
6505 ? access_private_node
6506 : access_public_node);
6508 if (previous_class_level
6509 && type != previous_class_level->this_entity
6510 && current_class_depth == 1)
6512 /* Forcibly remove any old class remnants. */
6513 invalidate_class_lookup_cache ();
6516 if (!previous_class_level
6517 || type != previous_class_level->this_entity
6518 || current_class_depth > 1)
6521 restore_class_cache ();
6524 /* When we exit a toplevel class scope, we save its binding level so
6525 that we can restore it quickly. Here, we've entered some other
6526 class, so we must invalidate our cache. */
6529 invalidate_class_lookup_cache (void)
6531 previous_class_level = NULL;
6534 /* Get out of the current class scope. If we were in a class scope
6535 previously, that is the one popped to. */
6542 current_class_depth--;
6543 current_class_name = current_class_stack[current_class_depth].name;
6544 current_class_type = current_class_stack[current_class_depth].type;
6545 current_access_specifier = current_class_stack[current_class_depth].access;
6546 if (current_class_stack[current_class_depth].names_used)
6547 splay_tree_delete (current_class_stack[current_class_depth].names_used);
6550 /* Mark the top of the class stack as hidden. */
6553 push_class_stack (void)
6555 if (current_class_depth)
6556 ++current_class_stack[current_class_depth - 1].hidden;
6559 /* Mark the top of the class stack as un-hidden. */
6562 pop_class_stack (void)
6564 if (current_class_depth)
6565 --current_class_stack[current_class_depth - 1].hidden;
6568 /* Returns 1 if the class type currently being defined is either T or
6569 a nested type of T. */
6572 currently_open_class (tree t)
6576 if (!CLASS_TYPE_P (t))
6579 t = TYPE_MAIN_VARIANT (t);
6581 /* We start looking from 1 because entry 0 is from global scope,
6583 for (i = current_class_depth; i > 0; --i)
6586 if (i == current_class_depth)
6587 c = current_class_type;
6590 if (current_class_stack[i].hidden)
6592 c = current_class_stack[i].type;
6596 if (same_type_p (c, t))
6602 /* If either current_class_type or one of its enclosing classes are derived
6603 from T, return the appropriate type. Used to determine how we found
6604 something via unqualified lookup. */
6607 currently_open_derived_class (tree t)
6611 /* The bases of a dependent type are unknown. */
6612 if (dependent_type_p (t))
6615 if (!current_class_type)
6618 if (DERIVED_FROM_P (t, current_class_type))
6619 return current_class_type;
6621 for (i = current_class_depth - 1; i > 0; --i)
6623 if (current_class_stack[i].hidden)
6625 if (DERIVED_FROM_P (t, current_class_stack[i].type))
6626 return current_class_stack[i].type;
6632 /* Returns the innermost class type which is not a lambda closure type. */
6635 current_nonlambda_class_type (void)
6639 /* We start looking from 1 because entry 0 is from global scope,
6641 for (i = current_class_depth; i > 0; --i)
6644 if (i == current_class_depth)
6645 c = current_class_type;
6648 if (current_class_stack[i].hidden)
6650 c = current_class_stack[i].type;
6654 if (!LAMBDA_TYPE_P (c))
6660 /* When entering a class scope, all enclosing class scopes' names with
6661 static meaning (static variables, static functions, types and
6662 enumerators) have to be visible. This recursive function calls
6663 pushclass for all enclosing class contexts until global or a local
6664 scope is reached. TYPE is the enclosed class. */
6667 push_nested_class (tree type)
6669 /* A namespace might be passed in error cases, like A::B:C. */
6670 if (type == NULL_TREE
6671 || !CLASS_TYPE_P (type))
6674 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
6679 /* Undoes a push_nested_class call. */
6682 pop_nested_class (void)
6684 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
6687 if (context && CLASS_TYPE_P (context))
6688 pop_nested_class ();
6691 /* Returns the number of extern "LANG" blocks we are nested within. */
6694 current_lang_depth (void)
6696 return VEC_length (tree, current_lang_base);
6699 /* Set global variables CURRENT_LANG_NAME to appropriate value
6700 so that behavior of name-mangling machinery is correct. */
6703 push_lang_context (tree name)
6705 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
6707 if (name == lang_name_cplusplus)
6709 current_lang_name = name;
6711 else if (name == lang_name_java)
6713 current_lang_name = name;
6714 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6715 (See record_builtin_java_type in decl.c.) However, that causes
6716 incorrect debug entries if these types are actually used.
6717 So we re-enable debug output after extern "Java". */
6718 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
6719 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
6720 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
6721 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
6722 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
6723 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
6724 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
6725 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
6727 else if (name == lang_name_c)
6729 current_lang_name = name;
6732 error ("language string %<\"%E\"%> not recognized", name);
6735 /* Get out of the current language scope. */
6738 pop_lang_context (void)
6740 current_lang_name = VEC_pop (tree, current_lang_base);
6743 /* Type instantiation routines. */
6745 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6746 matches the TARGET_TYPE. If there is no satisfactory match, return
6747 error_mark_node, and issue an error & warning messages under
6748 control of FLAGS. Permit pointers to member function if FLAGS
6749 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6750 a template-id, and EXPLICIT_TARGS are the explicitly provided
6753 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6754 is the base path used to reference those member functions. If
6755 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6756 resolved to a member function, access checks will be performed and
6757 errors issued if appropriate. */
6760 resolve_address_of_overloaded_function (tree target_type,
6762 tsubst_flags_t flags,
6764 tree explicit_targs,
6767 /* Here's what the standard says:
6771 If the name is a function template, template argument deduction
6772 is done, and if the argument deduction succeeds, the deduced
6773 arguments are used to generate a single template function, which
6774 is added to the set of overloaded functions considered.
6776 Non-member functions and static member functions match targets of
6777 type "pointer-to-function" or "reference-to-function." Nonstatic
6778 member functions match targets of type "pointer-to-member
6779 function;" the function type of the pointer to member is used to
6780 select the member function from the set of overloaded member
6781 functions. If a nonstatic member function is selected, the
6782 reference to the overloaded function name is required to have the
6783 form of a pointer to member as described in 5.3.1.
6785 If more than one function is selected, any template functions in
6786 the set are eliminated if the set also contains a non-template
6787 function, and any given template function is eliminated if the
6788 set contains a second template function that is more specialized
6789 than the first according to the partial ordering rules 14.5.5.2.
6790 After such eliminations, if any, there shall remain exactly one
6791 selected function. */
6794 /* We store the matches in a TREE_LIST rooted here. The functions
6795 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6796 interoperability with most_specialized_instantiation. */
6797 tree matches = NULL_TREE;
6799 tree target_fn_type;
6801 /* By the time we get here, we should be seeing only real
6802 pointer-to-member types, not the internal POINTER_TYPE to
6803 METHOD_TYPE representation. */
6804 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6805 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6807 gcc_assert (is_overloaded_fn (overload));
6809 /* Check that the TARGET_TYPE is reasonable. */
6810 if (TYPE_PTRFN_P (target_type))
6812 else if (TYPE_PTRMEMFUNC_P (target_type))
6813 /* This is OK, too. */
6815 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6816 /* This is OK, too. This comes from a conversion to reference
6818 target_type = build_reference_type (target_type);
6821 if (flags & tf_error)
6822 error ("cannot resolve overloaded function %qD based on"
6823 " conversion to type %qT",
6824 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6825 return error_mark_node;
6828 /* Non-member functions and static member functions match targets of type
6829 "pointer-to-function" or "reference-to-function." Nonstatic member
6830 functions match targets of type "pointer-to-member-function;" the
6831 function type of the pointer to member is used to select the member
6832 function from the set of overloaded member functions.
6834 So figure out the FUNCTION_TYPE that we want to match against. */
6835 target_fn_type = static_fn_type (target_type);
6837 /* If we can find a non-template function that matches, we can just
6838 use it. There's no point in generating template instantiations
6839 if we're just going to throw them out anyhow. But, of course, we
6840 can only do this when we don't *need* a template function. */
6845 for (fns = overload; fns; fns = OVL_NEXT (fns))
6847 tree fn = OVL_CURRENT (fns);
6849 if (TREE_CODE (fn) == TEMPLATE_DECL)
6850 /* We're not looking for templates just yet. */
6853 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6855 /* We're looking for a non-static member, and this isn't
6856 one, or vice versa. */
6859 /* Ignore functions which haven't been explicitly
6861 if (DECL_ANTICIPATED (fn))
6864 /* See if there's a match. */
6865 if (same_type_p (target_fn_type, static_fn_type (fn)))
6866 matches = tree_cons (fn, NULL_TREE, matches);
6870 /* Now, if we've already got a match (or matches), there's no need
6871 to proceed to the template functions. But, if we don't have a
6872 match we need to look at them, too. */
6875 tree target_arg_types;
6876 tree target_ret_type;
6879 unsigned int nargs, ia;
6882 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6883 target_ret_type = TREE_TYPE (target_fn_type);
6885 nargs = list_length (target_arg_types);
6886 args = XALLOCAVEC (tree, nargs);
6887 for (arg = target_arg_types, ia = 0;
6888 arg != NULL_TREE && arg != void_list_node;
6889 arg = TREE_CHAIN (arg), ++ia)
6890 args[ia] = TREE_VALUE (arg);
6893 for (fns = overload; fns; fns = OVL_NEXT (fns))
6895 tree fn = OVL_CURRENT (fns);
6899 if (TREE_CODE (fn) != TEMPLATE_DECL)
6900 /* We're only looking for templates. */
6903 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6905 /* We're not looking for a non-static member, and this is
6906 one, or vice versa. */
6909 /* Try to do argument deduction. */
6910 targs = make_tree_vec (DECL_NTPARMS (fn));
6911 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6912 target_ret_type, DEDUCE_EXACT,
6913 LOOKUP_NORMAL, false))
6914 /* Argument deduction failed. */
6917 /* Instantiate the template. */
6918 instantiation = instantiate_template (fn, targs, flags);
6919 if (instantiation == error_mark_node)
6920 /* Instantiation failed. */
6923 /* See if there's a match. */
6924 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
6925 matches = tree_cons (instantiation, fn, matches);
6928 /* Now, remove all but the most specialized of the matches. */
6931 tree match = most_specialized_instantiation (matches);
6933 if (match != error_mark_node)
6934 matches = tree_cons (TREE_PURPOSE (match),
6940 /* Now we should have exactly one function in MATCHES. */
6941 if (matches == NULL_TREE)
6943 /* There were *no* matches. */
6944 if (flags & tf_error)
6946 error ("no matches converting function %qD to type %q#T",
6947 DECL_NAME (OVL_CURRENT (overload)),
6950 print_candidates (overload);
6952 return error_mark_node;
6954 else if (TREE_CHAIN (matches))
6956 /* There were too many matches. First check if they're all
6957 the same function. */
6960 fn = TREE_PURPOSE (matches);
6961 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6962 if (!decls_match (fn, TREE_PURPOSE (match)))
6967 if (flags & tf_error)
6969 error ("converting overloaded function %qD to type %q#T is ambiguous",
6970 DECL_NAME (OVL_FUNCTION (overload)),
6973 /* Since print_candidates expects the functions in the
6974 TREE_VALUE slot, we flip them here. */
6975 for (match = matches; match; match = TREE_CHAIN (match))
6976 TREE_VALUE (match) = TREE_PURPOSE (match);
6978 print_candidates (matches);
6981 return error_mark_node;
6985 /* Good, exactly one match. Now, convert it to the correct type. */
6986 fn = TREE_PURPOSE (matches);
6988 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6989 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6991 static int explained;
6993 if (!(flags & tf_error))
6994 return error_mark_node;
6996 permerror (input_location, "assuming pointer to member %qD", fn);
6999 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
7004 /* If we're doing overload resolution purely for the purpose of
7005 determining conversion sequences, we should not consider the
7006 function used. If this conversion sequence is selected, the
7007 function will be marked as used at this point. */
7008 if (!(flags & tf_conv))
7010 /* Make =delete work with SFINAE. */
7011 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
7012 return error_mark_node;
7017 /* We could not check access to member functions when this
7018 expression was originally created since we did not know at that
7019 time to which function the expression referred. */
7020 if (!(flags & tf_no_access_control)
7021 && DECL_FUNCTION_MEMBER_P (fn))
7023 gcc_assert (access_path);
7024 perform_or_defer_access_check (access_path, fn, fn);
7027 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
7028 return cp_build_addr_expr (fn, flags);
7031 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
7032 will mark the function as addressed, but here we must do it
7034 cxx_mark_addressable (fn);
7040 /* This function will instantiate the type of the expression given in
7041 RHS to match the type of LHSTYPE. If errors exist, then return
7042 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
7043 we complain on errors. If we are not complaining, never modify rhs,
7044 as overload resolution wants to try many possible instantiations, in
7045 the hope that at least one will work.
7047 For non-recursive calls, LHSTYPE should be a function, pointer to
7048 function, or a pointer to member function. */
7051 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
7053 tsubst_flags_t flags_in = flags;
7054 tree access_path = NULL_TREE;
7056 flags &= ~tf_ptrmem_ok;
7058 if (lhstype == unknown_type_node)
7060 if (flags & tf_error)
7061 error ("not enough type information");
7062 return error_mark_node;
7065 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
7067 if (same_type_p (lhstype, TREE_TYPE (rhs)))
7069 if (flag_ms_extensions
7070 && TYPE_PTRMEMFUNC_P (lhstype)
7071 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
7072 /* Microsoft allows `A::f' to be resolved to a
7073 pointer-to-member. */
7077 if (flags & tf_error)
7078 error ("cannot convert %qE from type %qT to type %qT",
7079 rhs, TREE_TYPE (rhs), lhstype);
7080 return error_mark_node;
7084 if (BASELINK_P (rhs))
7086 access_path = BASELINK_ACCESS_BINFO (rhs);
7087 rhs = BASELINK_FUNCTIONS (rhs);
7090 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
7091 deduce any type information. */
7092 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
7094 if (flags & tf_error)
7095 error ("not enough type information");
7096 return error_mark_node;
7099 /* There only a few kinds of expressions that may have a type
7100 dependent on overload resolution. */
7101 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
7102 || TREE_CODE (rhs) == COMPONENT_REF
7103 || really_overloaded_fn (rhs)
7104 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
7106 /* This should really only be used when attempting to distinguish
7107 what sort of a pointer to function we have. For now, any
7108 arithmetic operation which is not supported on pointers
7109 is rejected as an error. */
7111 switch (TREE_CODE (rhs))
7115 tree member = TREE_OPERAND (rhs, 1);
7117 member = instantiate_type (lhstype, member, flags);
7118 if (member != error_mark_node
7119 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
7120 /* Do not lose object's side effects. */
7121 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
7122 TREE_OPERAND (rhs, 0), member);
7127 rhs = TREE_OPERAND (rhs, 1);
7128 if (BASELINK_P (rhs))
7129 return instantiate_type (lhstype, rhs, flags_in);
7131 /* This can happen if we are forming a pointer-to-member for a
7133 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
7137 case TEMPLATE_ID_EXPR:
7139 tree fns = TREE_OPERAND (rhs, 0);
7140 tree args = TREE_OPERAND (rhs, 1);
7143 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
7144 /*template_only=*/true,
7151 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
7152 /*template_only=*/false,
7153 /*explicit_targs=*/NULL_TREE,
7158 if (PTRMEM_OK_P (rhs))
7159 flags |= tf_ptrmem_ok;
7161 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
7165 return error_mark_node;
7170 return error_mark_node;
7173 /* Return the name of the virtual function pointer field
7174 (as an IDENTIFIER_NODE) for the given TYPE. Note that
7175 this may have to look back through base types to find the
7176 ultimate field name. (For single inheritance, these could
7177 all be the same name. Who knows for multiple inheritance). */
7180 get_vfield_name (tree type)
7182 tree binfo, base_binfo;
7185 for (binfo = TYPE_BINFO (type);
7186 BINFO_N_BASE_BINFOS (binfo);
7189 base_binfo = BINFO_BASE_BINFO (binfo, 0);
7191 if (BINFO_VIRTUAL_P (base_binfo)
7192 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
7196 type = BINFO_TYPE (binfo);
7197 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
7198 + TYPE_NAME_LENGTH (type) + 2);
7199 sprintf (buf, VFIELD_NAME_FORMAT,
7200 IDENTIFIER_POINTER (constructor_name (type)));
7201 return get_identifier (buf);
7205 print_class_statistics (void)
7207 #ifdef GATHER_STATISTICS
7208 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
7209 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
7212 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
7213 n_vtables, n_vtable_searches);
7214 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
7215 n_vtable_entries, n_vtable_elems);
7220 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
7221 according to [class]:
7222 The class-name is also inserted
7223 into the scope of the class itself. For purposes of access checking,
7224 the inserted class name is treated as if it were a public member name. */
7227 build_self_reference (void)
7229 tree name = constructor_name (current_class_type);
7230 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
7233 DECL_NONLOCAL (value) = 1;
7234 DECL_CONTEXT (value) = current_class_type;
7235 DECL_ARTIFICIAL (value) = 1;
7236 SET_DECL_SELF_REFERENCE_P (value);
7237 set_underlying_type (value);
7239 if (processing_template_decl)
7240 value = push_template_decl (value);
7242 saved_cas = current_access_specifier;
7243 current_access_specifier = access_public_node;
7244 finish_member_declaration (value);
7245 current_access_specifier = saved_cas;
7248 /* Returns 1 if TYPE contains only padding bytes. */
7251 is_empty_class (tree type)
7253 if (type == error_mark_node)
7256 if (! CLASS_TYPE_P (type))
7259 /* In G++ 3.2, whether or not a class was empty was determined by
7260 looking at its size. */
7261 if (abi_version_at_least (2))
7262 return CLASSTYPE_EMPTY_P (type);
7264 return integer_zerop (CLASSTYPE_SIZE (type));
7267 /* Returns true if TYPE contains an empty class. */
7270 contains_empty_class_p (tree type)
7272 if (is_empty_class (type))
7274 if (CLASS_TYPE_P (type))
7281 for (binfo = TYPE_BINFO (type), i = 0;
7282 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7283 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
7285 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
7286 if (TREE_CODE (field) == FIELD_DECL
7287 && !DECL_ARTIFICIAL (field)
7288 && is_empty_class (TREE_TYPE (field)))
7291 else if (TREE_CODE (type) == ARRAY_TYPE)
7292 return contains_empty_class_p (TREE_TYPE (type));
7296 /* Returns true if TYPE contains no actual data, just various
7297 possible combinations of empty classes and possibly a vptr. */
7300 is_really_empty_class (tree type)
7302 if (CLASS_TYPE_P (type))
7309 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
7310 out, but we'd like to be able to check this before then. */
7311 if (COMPLETE_TYPE_P (type) && is_empty_class (type))
7314 for (binfo = TYPE_BINFO (type), i = 0;
7315 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7316 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
7318 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
7319 if (TREE_CODE (field) == FIELD_DECL
7320 && !DECL_ARTIFICIAL (field)
7321 && !is_really_empty_class (TREE_TYPE (field)))
7325 else if (TREE_CODE (type) == ARRAY_TYPE)
7326 return is_really_empty_class (TREE_TYPE (type));
7330 /* Note that NAME was looked up while the current class was being
7331 defined and that the result of that lookup was DECL. */
7334 maybe_note_name_used_in_class (tree name, tree decl)
7336 splay_tree names_used;
7338 /* If we're not defining a class, there's nothing to do. */
7339 if (!(innermost_scope_kind() == sk_class
7340 && TYPE_BEING_DEFINED (current_class_type)
7341 && !LAMBDA_TYPE_P (current_class_type)))
7344 /* If there's already a binding for this NAME, then we don't have
7345 anything to worry about. */
7346 if (lookup_member (current_class_type, name,
7347 /*protect=*/0, /*want_type=*/false, tf_warning_or_error))
7350 if (!current_class_stack[current_class_depth - 1].names_used)
7351 current_class_stack[current_class_depth - 1].names_used
7352 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
7353 names_used = current_class_stack[current_class_depth - 1].names_used;
7355 splay_tree_insert (names_used,
7356 (splay_tree_key) name,
7357 (splay_tree_value) decl);
7360 /* Note that NAME was declared (as DECL) in the current class. Check
7361 to see that the declaration is valid. */
7364 note_name_declared_in_class (tree name, tree decl)
7366 splay_tree names_used;
7369 /* Look to see if we ever used this name. */
7371 = current_class_stack[current_class_depth - 1].names_used;
7374 /* The C language allows members to be declared with a type of the same
7375 name, and the C++ standard says this diagnostic is not required. So
7376 allow it in extern "C" blocks unless predantic is specified.
7377 Allow it in all cases if -ms-extensions is specified. */
7378 if ((!pedantic && current_lang_name == lang_name_c)
7379 || flag_ms_extensions)
7381 n = splay_tree_lookup (names_used, (splay_tree_key) name);
7384 /* [basic.scope.class]
7386 A name N used in a class S shall refer to the same declaration
7387 in its context and when re-evaluated in the completed scope of
7389 permerror (input_location, "declaration of %q#D", decl);
7390 permerror (input_location, "changes meaning of %qD from %q+#D",
7391 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
7395 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
7396 Secondary vtables are merged with primary vtables; this function
7397 will return the VAR_DECL for the primary vtable. */
7400 get_vtbl_decl_for_binfo (tree binfo)
7404 decl = BINFO_VTABLE (binfo);
7405 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
7407 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
7408 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
7411 gcc_assert (TREE_CODE (decl) == VAR_DECL);
7416 /* Returns the binfo for the primary base of BINFO. If the resulting
7417 BINFO is a virtual base, and it is inherited elsewhere in the
7418 hierarchy, then the returned binfo might not be the primary base of
7419 BINFO in the complete object. Check BINFO_PRIMARY_P or
7420 BINFO_LOST_PRIMARY_P to be sure. */
7423 get_primary_binfo (tree binfo)
7427 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
7431 return copied_binfo (primary_base, binfo);
7434 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
7437 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
7440 fprintf (stream, "%*s", indent, "");
7444 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
7445 INDENT should be zero when called from the top level; it is
7446 incremented recursively. IGO indicates the next expected BINFO in
7447 inheritance graph ordering. */
7450 dump_class_hierarchy_r (FILE *stream,
7460 indented = maybe_indent_hierarchy (stream, indent, 0);
7461 fprintf (stream, "%s (0x%lx) ",
7462 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
7463 (unsigned long) binfo);
7466 fprintf (stream, "alternative-path\n");
7469 igo = TREE_CHAIN (binfo);
7471 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
7472 tree_low_cst (BINFO_OFFSET (binfo), 0));
7473 if (is_empty_class (BINFO_TYPE (binfo)))
7474 fprintf (stream, " empty");
7475 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
7476 fprintf (stream, " nearly-empty");
7477 if (BINFO_VIRTUAL_P (binfo))
7478 fprintf (stream, " virtual");
7479 fprintf (stream, "\n");
7482 if (BINFO_PRIMARY_P (binfo))
7484 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7485 fprintf (stream, " primary-for %s (0x%lx)",
7486 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
7487 TFF_PLAIN_IDENTIFIER),
7488 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
7490 if (BINFO_LOST_PRIMARY_P (binfo))
7492 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7493 fprintf (stream, " lost-primary");
7496 fprintf (stream, "\n");
7498 if (!(flags & TDF_SLIM))
7502 if (BINFO_SUBVTT_INDEX (binfo))
7504 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7505 fprintf (stream, " subvttidx=%s",
7506 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
7507 TFF_PLAIN_IDENTIFIER));
7509 if (BINFO_VPTR_INDEX (binfo))
7511 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7512 fprintf (stream, " vptridx=%s",
7513 expr_as_string (BINFO_VPTR_INDEX (binfo),
7514 TFF_PLAIN_IDENTIFIER));
7516 if (BINFO_VPTR_FIELD (binfo))
7518 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7519 fprintf (stream, " vbaseoffset=%s",
7520 expr_as_string (BINFO_VPTR_FIELD (binfo),
7521 TFF_PLAIN_IDENTIFIER));
7523 if (BINFO_VTABLE (binfo))
7525 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7526 fprintf (stream, " vptr=%s",
7527 expr_as_string (BINFO_VTABLE (binfo),
7528 TFF_PLAIN_IDENTIFIER));
7532 fprintf (stream, "\n");
7535 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
7536 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
7541 /* Dump the BINFO hierarchy for T. */
7544 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
7546 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7547 fprintf (stream, " size=%lu align=%lu\n",
7548 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
7549 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
7550 fprintf (stream, " base size=%lu base align=%lu\n",
7551 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
7553 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
7555 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
7556 fprintf (stream, "\n");
7559 /* Debug interface to hierarchy dumping. */
7562 debug_class (tree t)
7564 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
7568 dump_class_hierarchy (tree t)
7571 FILE *stream = dump_begin (TDI_class, &flags);
7575 dump_class_hierarchy_1 (stream, flags, t);
7576 dump_end (TDI_class, stream);
7581 dump_array (FILE * stream, tree decl)
7584 unsigned HOST_WIDE_INT ix;
7586 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
7588 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
7590 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
7591 fprintf (stream, " %s entries",
7592 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
7593 TFF_PLAIN_IDENTIFIER));
7594 fprintf (stream, "\n");
7596 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
7598 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
7599 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
7603 dump_vtable (tree t, tree binfo, tree vtable)
7606 FILE *stream = dump_begin (TDI_class, &flags);
7611 if (!(flags & TDF_SLIM))
7613 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
7615 fprintf (stream, "%s for %s",
7616 ctor_vtbl_p ? "Construction vtable" : "Vtable",
7617 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
7620 if (!BINFO_VIRTUAL_P (binfo))
7621 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
7622 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7624 fprintf (stream, "\n");
7625 dump_array (stream, vtable);
7626 fprintf (stream, "\n");
7629 dump_end (TDI_class, stream);
7633 dump_vtt (tree t, tree vtt)
7636 FILE *stream = dump_begin (TDI_class, &flags);
7641 if (!(flags & TDF_SLIM))
7643 fprintf (stream, "VTT for %s\n",
7644 type_as_string (t, TFF_PLAIN_IDENTIFIER));
7645 dump_array (stream, vtt);
7646 fprintf (stream, "\n");
7649 dump_end (TDI_class, stream);
7652 /* Dump a function or thunk and its thunkees. */
7655 dump_thunk (FILE *stream, int indent, tree thunk)
7657 static const char spaces[] = " ";
7658 tree name = DECL_NAME (thunk);
7661 fprintf (stream, "%.*s%p %s %s", indent, spaces,
7663 !DECL_THUNK_P (thunk) ? "function"
7664 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
7665 name ? IDENTIFIER_POINTER (name) : "<unset>");
7666 if (DECL_THUNK_P (thunk))
7668 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
7669 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
7671 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
7672 if (!virtual_adjust)
7674 else if (DECL_THIS_THUNK_P (thunk))
7675 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
7676 tree_low_cst (virtual_adjust, 0));
7678 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
7679 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
7680 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
7681 if (THUNK_ALIAS (thunk))
7682 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
7684 fprintf (stream, "\n");
7685 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
7686 dump_thunk (stream, indent + 2, thunks);
7689 /* Dump the thunks for FN. */
7692 debug_thunks (tree fn)
7694 dump_thunk (stderr, 0, fn);
7697 /* Virtual function table initialization. */
7699 /* Create all the necessary vtables for T and its base classes. */
7702 finish_vtbls (tree t)
7705 VEC(constructor_elt,gc) *v = NULL;
7706 tree vtable = BINFO_VTABLE (TYPE_BINFO (t));
7708 /* We lay out the primary and secondary vtables in one contiguous
7709 vtable. The primary vtable is first, followed by the non-virtual
7710 secondary vtables in inheritance graph order. */
7711 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t),
7714 /* Then come the virtual bases, also in inheritance graph order. */
7715 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
7717 if (!BINFO_VIRTUAL_P (vbase))
7719 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), vtable, t, &v);
7722 if (BINFO_VTABLE (TYPE_BINFO (t)))
7723 initialize_vtable (TYPE_BINFO (t), v);
7726 /* Initialize the vtable for BINFO with the INITS. */
7729 initialize_vtable (tree binfo, VEC(constructor_elt,gc) *inits)
7733 layout_vtable_decl (binfo, VEC_length (constructor_elt, inits));
7734 decl = get_vtbl_decl_for_binfo (binfo);
7735 initialize_artificial_var (decl, inits);
7736 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
7739 /* Build the VTT (virtual table table) for T.
7740 A class requires a VTT if it has virtual bases.
7743 1 - primary virtual pointer for complete object T
7744 2 - secondary VTTs for each direct non-virtual base of T which requires a
7746 3 - secondary virtual pointers for each direct or indirect base of T which
7747 has virtual bases or is reachable via a virtual path from T.
7748 4 - secondary VTTs for each direct or indirect virtual base of T.
7750 Secondary VTTs look like complete object VTTs without part 4. */
7758 VEC(constructor_elt,gc) *inits;
7760 /* Build up the initializers for the VTT. */
7762 index = size_zero_node;
7763 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7765 /* If we didn't need a VTT, we're done. */
7769 /* Figure out the type of the VTT. */
7770 type = build_array_of_n_type (const_ptr_type_node,
7771 VEC_length (constructor_elt, inits));
7773 /* Now, build the VTT object itself. */
7774 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7775 initialize_artificial_var (vtt, inits);
7776 /* Add the VTT to the vtables list. */
7777 DECL_CHAIN (vtt) = DECL_CHAIN (CLASSTYPE_VTABLES (t));
7778 DECL_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7783 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7784 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7785 and CHAIN the vtable pointer for this binfo after construction is
7786 complete. VALUE can also be another BINFO, in which case we recurse. */
7789 binfo_ctor_vtable (tree binfo)
7795 vt = BINFO_VTABLE (binfo);
7796 if (TREE_CODE (vt) == TREE_LIST)
7797 vt = TREE_VALUE (vt);
7798 if (TREE_CODE (vt) == TREE_BINFO)
7807 /* Data for secondary VTT initialization. */
7808 typedef struct secondary_vptr_vtt_init_data_s
7810 /* Is this the primary VTT? */
7813 /* Current index into the VTT. */
7816 /* Vector of initializers built up. */
7817 VEC(constructor_elt,gc) *inits;
7819 /* The type being constructed by this secondary VTT. */
7820 tree type_being_constructed;
7821 } secondary_vptr_vtt_init_data;
7823 /* Recursively build the VTT-initializer for BINFO (which is in the
7824 hierarchy dominated by T). INITS points to the end of the initializer
7825 list to date. INDEX is the VTT index where the next element will be
7826 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7827 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7828 for virtual bases of T. When it is not so, we build the constructor
7829 vtables for the BINFO-in-T variant. */
7832 build_vtt_inits (tree binfo, tree t, VEC(constructor_elt,gc) **inits, tree *index)
7837 secondary_vptr_vtt_init_data data;
7838 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7840 /* We only need VTTs for subobjects with virtual bases. */
7841 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7844 /* We need to use a construction vtable if this is not the primary
7848 build_ctor_vtbl_group (binfo, t);
7850 /* Record the offset in the VTT where this sub-VTT can be found. */
7851 BINFO_SUBVTT_INDEX (binfo) = *index;
7854 /* Add the address of the primary vtable for the complete object. */
7855 init = binfo_ctor_vtable (binfo);
7856 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7859 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7860 BINFO_VPTR_INDEX (binfo) = *index;
7862 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7864 /* Recursively add the secondary VTTs for non-virtual bases. */
7865 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7866 if (!BINFO_VIRTUAL_P (b))
7867 build_vtt_inits (b, t, inits, index);
7869 /* Add secondary virtual pointers for all subobjects of BINFO with
7870 either virtual bases or reachable along a virtual path, except
7871 subobjects that are non-virtual primary bases. */
7872 data.top_level_p = top_level_p;
7873 data.index = *index;
7874 data.inits = *inits;
7875 data.type_being_constructed = BINFO_TYPE (binfo);
7877 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7879 *index = data.index;
7881 /* data.inits might have grown as we added secondary virtual pointers.
7882 Make sure our caller knows about the new vector. */
7883 *inits = data.inits;
7886 /* Add the secondary VTTs for virtual bases in inheritance graph
7888 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7890 if (!BINFO_VIRTUAL_P (b))
7893 build_vtt_inits (b, t, inits, index);
7896 /* Remove the ctor vtables we created. */
7897 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7900 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7901 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7904 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7906 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7908 /* We don't care about bases that don't have vtables. */
7909 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7910 return dfs_skip_bases;
7912 /* We're only interested in proper subobjects of the type being
7914 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7917 /* We're only interested in bases with virtual bases or reachable
7918 via a virtual path from the type being constructed. */
7919 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7920 || binfo_via_virtual (binfo, data->type_being_constructed)))
7921 return dfs_skip_bases;
7923 /* We're not interested in non-virtual primary bases. */
7924 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7927 /* Record the index where this secondary vptr can be found. */
7928 if (data->top_level_p)
7930 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7931 BINFO_VPTR_INDEX (binfo) = data->index;
7933 if (BINFO_VIRTUAL_P (binfo))
7935 /* It's a primary virtual base, and this is not a
7936 construction vtable. Find the base this is primary of in
7937 the inheritance graph, and use that base's vtable
7939 while (BINFO_PRIMARY_P (binfo))
7940 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7944 /* Add the initializer for the secondary vptr itself. */
7945 CONSTRUCTOR_APPEND_ELT (data->inits, NULL_TREE, binfo_ctor_vtable (binfo));
7947 /* Advance the vtt index. */
7948 data->index = size_binop (PLUS_EXPR, data->index,
7949 TYPE_SIZE_UNIT (ptr_type_node));
7954 /* Called from build_vtt_inits via dfs_walk. After building
7955 constructor vtables and generating the sub-vtt from them, we need
7956 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7957 binfo of the base whose sub vtt was generated. */
7960 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7962 tree vtable = BINFO_VTABLE (binfo);
7964 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7965 /* If this class has no vtable, none of its bases do. */
7966 return dfs_skip_bases;
7969 /* This might be a primary base, so have no vtable in this
7973 /* If we scribbled the construction vtable vptr into BINFO, clear it
7975 if (TREE_CODE (vtable) == TREE_LIST
7976 && (TREE_PURPOSE (vtable) == (tree) data))
7977 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7982 /* Build the construction vtable group for BINFO which is in the
7983 hierarchy dominated by T. */
7986 build_ctor_vtbl_group (tree binfo, tree t)
7992 VEC(constructor_elt,gc) *v;
7994 /* See if we've already created this construction vtable group. */
7995 id = mangle_ctor_vtbl_for_type (t, binfo);
7996 if (IDENTIFIER_GLOBAL_VALUE (id))
7999 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
8000 /* Build a version of VTBL (with the wrong type) for use in
8001 constructing the addresses of secondary vtables in the
8002 construction vtable group. */
8003 vtbl = build_vtable (t, id, ptr_type_node);
8004 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
8007 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
8008 binfo, vtbl, t, &v);
8010 /* Add the vtables for each of our virtual bases using the vbase in T
8012 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
8014 vbase = TREE_CHAIN (vbase))
8018 if (!BINFO_VIRTUAL_P (vbase))
8020 b = copied_binfo (vbase, binfo);
8022 accumulate_vtbl_inits (b, vbase, binfo, vtbl, t, &v);
8025 /* Figure out the type of the construction vtable. */
8026 type = build_array_of_n_type (vtable_entry_type,
8027 VEC_length (constructor_elt, v));
8029 TREE_TYPE (vtbl) = type;
8030 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
8031 layout_decl (vtbl, 0);
8033 /* Initialize the construction vtable. */
8034 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
8035 initialize_artificial_var (vtbl, v);
8036 dump_vtable (t, binfo, vtbl);
8039 /* Add the vtbl initializers for BINFO (and its bases other than
8040 non-virtual primaries) to the list of INITS. BINFO is in the
8041 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
8042 the constructor the vtbl inits should be accumulated for. (If this
8043 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
8044 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
8045 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
8046 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
8047 but are not necessarily the same in terms of layout. */
8050 accumulate_vtbl_inits (tree binfo,
8055 VEC(constructor_elt,gc) **inits)
8059 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8061 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
8063 /* If it doesn't have a vptr, we don't do anything. */
8064 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
8067 /* If we're building a construction vtable, we're not interested in
8068 subobjects that don't require construction vtables. */
8070 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
8071 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
8074 /* Build the initializers for the BINFO-in-T vtable. */
8075 dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, vtbl, t, inits);
8077 /* Walk the BINFO and its bases. We walk in preorder so that as we
8078 initialize each vtable we can figure out at what offset the
8079 secondary vtable lies from the primary vtable. We can't use
8080 dfs_walk here because we need to iterate through bases of BINFO
8081 and RTTI_BINFO simultaneously. */
8082 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8084 /* Skip virtual bases. */
8085 if (BINFO_VIRTUAL_P (base_binfo))
8087 accumulate_vtbl_inits (base_binfo,
8088 BINFO_BASE_BINFO (orig_binfo, i),
8089 rtti_binfo, vtbl, t,
8094 /* Called from accumulate_vtbl_inits. Adds the initializers for the
8095 BINFO vtable to L. */
8098 dfs_accumulate_vtbl_inits (tree binfo,
8103 VEC(constructor_elt,gc) **l)
8105 tree vtbl = NULL_TREE;
8106 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8110 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
8112 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
8113 primary virtual base. If it is not the same primary in
8114 the hierarchy of T, we'll need to generate a ctor vtable
8115 for it, to place at its location in T. If it is the same
8116 primary, we still need a VTT entry for the vtable, but it
8117 should point to the ctor vtable for the base it is a
8118 primary for within the sub-hierarchy of RTTI_BINFO.
8120 There are three possible cases:
8122 1) We are in the same place.
8123 2) We are a primary base within a lost primary virtual base of
8125 3) We are primary to something not a base of RTTI_BINFO. */
8128 tree last = NULL_TREE;
8130 /* First, look through the bases we are primary to for RTTI_BINFO
8131 or a virtual base. */
8133 while (BINFO_PRIMARY_P (b))
8135 b = BINFO_INHERITANCE_CHAIN (b);
8137 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
8140 /* If we run out of primary links, keep looking down our
8141 inheritance chain; we might be an indirect primary. */
8142 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
8143 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
8147 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
8148 base B and it is a base of RTTI_BINFO, this is case 2. In
8149 either case, we share our vtable with LAST, i.e. the
8150 derived-most base within B of which we are a primary. */
8152 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
8153 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
8154 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
8155 binfo_ctor_vtable after everything's been set up. */
8158 /* Otherwise, this is case 3 and we get our own. */
8160 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
8163 n_inits = VEC_length (constructor_elt, *l);
8170 /* Add the initializer for this vtable. */
8171 build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
8172 &non_fn_entries, l);
8174 /* Figure out the position to which the VPTR should point. */
8175 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, orig_vtbl);
8176 index = size_binop (MULT_EXPR,
8177 TYPE_SIZE_UNIT (vtable_entry_type),
8178 size_int (non_fn_entries + n_inits));
8179 vtbl = fold_build_pointer_plus (vtbl, index);
8183 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
8184 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
8185 straighten this out. */
8186 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
8187 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
8188 /* Throw away any unneeded intializers. */
8189 VEC_truncate (constructor_elt, *l, n_inits);
8191 /* For an ordinary vtable, set BINFO_VTABLE. */
8192 BINFO_VTABLE (binfo) = vtbl;
8195 static GTY(()) tree abort_fndecl_addr;
8197 /* Construct the initializer for BINFO's virtual function table. BINFO
8198 is part of the hierarchy dominated by T. If we're building a
8199 construction vtable, the ORIG_BINFO is the binfo we should use to
8200 find the actual function pointers to put in the vtable - but they
8201 can be overridden on the path to most-derived in the graph that
8202 ORIG_BINFO belongs. Otherwise,
8203 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
8204 BINFO that should be indicated by the RTTI information in the
8205 vtable; it will be a base class of T, rather than T itself, if we
8206 are building a construction vtable.
8208 The value returned is a TREE_LIST suitable for wrapping in a
8209 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
8210 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
8211 number of non-function entries in the vtable.
8213 It might seem that this function should never be called with a
8214 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
8215 base is always subsumed by a derived class vtable. However, when
8216 we are building construction vtables, we do build vtables for
8217 primary bases; we need these while the primary base is being
8221 build_vtbl_initializer (tree binfo,
8225 int* non_fn_entries_p,
8226 VEC(constructor_elt,gc) **inits)
8232 VEC(tree,gc) *vbases;
8235 /* Initialize VID. */
8236 memset (&vid, 0, sizeof (vid));
8239 vid.rtti_binfo = rtti_binfo;
8240 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
8241 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8242 vid.generate_vcall_entries = true;
8243 /* The first vbase or vcall offset is at index -3 in the vtable. */
8244 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
8246 /* Add entries to the vtable for RTTI. */
8247 build_rtti_vtbl_entries (binfo, &vid);
8249 /* Create an array for keeping track of the functions we've
8250 processed. When we see multiple functions with the same
8251 signature, we share the vcall offsets. */
8252 vid.fns = VEC_alloc (tree, gc, 32);
8253 /* Add the vcall and vbase offset entries. */
8254 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
8256 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
8257 build_vbase_offset_vtbl_entries. */
8258 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
8259 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
8260 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
8262 /* If the target requires padding between data entries, add that now. */
8263 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
8265 int n_entries = VEC_length (constructor_elt, vid.inits);
8267 VEC_safe_grow (constructor_elt, gc, vid.inits,
8268 TARGET_VTABLE_DATA_ENTRY_DISTANCE * n_entries);
8270 /* Move data entries into their new positions and add padding
8271 after the new positions. Iterate backwards so we don't
8272 overwrite entries that we would need to process later. */
8273 for (ix = n_entries - 1;
8274 VEC_iterate (constructor_elt, vid.inits, ix, e);
8278 int new_position = (TARGET_VTABLE_DATA_ENTRY_DISTANCE * ix
8279 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE - 1));
8281 VEC_replace (constructor_elt, vid.inits, new_position, e);
8283 for (j = 1; j < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++j)
8285 constructor_elt *f = VEC_index (constructor_elt, vid.inits,
8287 f->index = NULL_TREE;
8288 f->value = build1 (NOP_EXPR, vtable_entry_type,
8294 if (non_fn_entries_p)
8295 *non_fn_entries_p = VEC_length (constructor_elt, vid.inits);
8297 /* The initializers for virtual functions were built up in reverse
8298 order. Straighten them out and add them to the running list in one
8300 jx = VEC_length (constructor_elt, *inits);
8301 VEC_safe_grow (constructor_elt, gc, *inits,
8302 (jx + VEC_length (constructor_elt, vid.inits)));
8304 for (ix = VEC_length (constructor_elt, vid.inits) - 1;
8305 VEC_iterate (constructor_elt, vid.inits, ix, e);
8307 VEC_replace (constructor_elt, *inits, jx, e);
8309 /* Go through all the ordinary virtual functions, building up
8311 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
8315 tree fn, fn_original;
8316 tree init = NULL_TREE;
8320 if (DECL_THUNK_P (fn))
8322 if (!DECL_NAME (fn))
8324 if (THUNK_ALIAS (fn))
8326 fn = THUNK_ALIAS (fn);
8329 fn_original = THUNK_TARGET (fn);
8332 /* If the only definition of this function signature along our
8333 primary base chain is from a lost primary, this vtable slot will
8334 never be used, so just zero it out. This is important to avoid
8335 requiring extra thunks which cannot be generated with the function.
8337 We first check this in update_vtable_entry_for_fn, so we handle
8338 restored primary bases properly; we also need to do it here so we
8339 zero out unused slots in ctor vtables, rather than filling them
8340 with erroneous values (though harmless, apart from relocation
8342 if (BV_LOST_PRIMARY (v))
8343 init = size_zero_node;
8347 /* Pull the offset for `this', and the function to call, out of
8349 delta = BV_DELTA (v);
8350 vcall_index = BV_VCALL_INDEX (v);
8352 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
8353 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
8355 /* You can't call an abstract virtual function; it's abstract.
8356 So, we replace these functions with __pure_virtual. */
8357 if (DECL_PURE_VIRTUAL_P (fn_original))
8360 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8362 if (abort_fndecl_addr == NULL)
8364 = fold_convert (vfunc_ptr_type_node,
8365 build_fold_addr_expr (fn));
8366 init = abort_fndecl_addr;
8369 /* Likewise for deleted virtuals. */
8370 else if (DECL_DELETED_FN (fn_original))
8372 fn = get_identifier ("__cxa_deleted_virtual");
8373 if (!get_global_value_if_present (fn, &fn))
8374 fn = push_library_fn (fn, (build_function_type_list
8375 (void_type_node, NULL_TREE)),
8377 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8378 init = fold_convert (vfunc_ptr_type_node,
8379 build_fold_addr_expr (fn));
8383 if (!integer_zerop (delta) || vcall_index)
8385 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
8386 if (!DECL_NAME (fn))
8389 /* Take the address of the function, considering it to be of an
8390 appropriate generic type. */
8391 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8392 init = fold_convert (vfunc_ptr_type_node,
8393 build_fold_addr_expr (fn));
8397 /* And add it to the chain of initializers. */
8398 if (TARGET_VTABLE_USES_DESCRIPTORS)
8401 if (init == size_zero_node)
8402 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8403 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8405 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8407 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
8408 fn, build_int_cst (NULL_TREE, i));
8409 TREE_CONSTANT (fdesc) = 1;
8411 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, fdesc);
8415 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8419 /* Adds to vid->inits the initializers for the vbase and vcall
8420 offsets in BINFO, which is in the hierarchy dominated by T. */
8423 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
8427 /* If this is a derived class, we must first create entries
8428 corresponding to the primary base class. */
8429 b = get_primary_binfo (binfo);
8431 build_vcall_and_vbase_vtbl_entries (b, vid);
8433 /* Add the vbase entries for this base. */
8434 build_vbase_offset_vtbl_entries (binfo, vid);
8435 /* Add the vcall entries for this base. */
8436 build_vcall_offset_vtbl_entries (binfo, vid);
8439 /* Returns the initializers for the vbase offset entries in the vtable
8440 for BINFO (which is part of the class hierarchy dominated by T), in
8441 reverse order. VBASE_OFFSET_INDEX gives the vtable index
8442 where the next vbase offset will go. */
8445 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8449 tree non_primary_binfo;
8451 /* If there are no virtual baseclasses, then there is nothing to
8453 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
8458 /* We might be a primary base class. Go up the inheritance hierarchy
8459 until we find the most derived class of which we are a primary base:
8460 it is the offset of that which we need to use. */
8461 non_primary_binfo = binfo;
8462 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8466 /* If we have reached a virtual base, then it must be a primary
8467 base (possibly multi-level) of vid->binfo, or we wouldn't
8468 have called build_vcall_and_vbase_vtbl_entries for it. But it
8469 might be a lost primary, so just skip down to vid->binfo. */
8470 if (BINFO_VIRTUAL_P (non_primary_binfo))
8472 non_primary_binfo = vid->binfo;
8476 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8477 if (get_primary_binfo (b) != non_primary_binfo)
8479 non_primary_binfo = b;
8482 /* Go through the virtual bases, adding the offsets. */
8483 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
8485 vbase = TREE_CHAIN (vbase))
8490 if (!BINFO_VIRTUAL_P (vbase))
8493 /* Find the instance of this virtual base in the complete
8495 b = copied_binfo (vbase, binfo);
8497 /* If we've already got an offset for this virtual base, we
8498 don't need another one. */
8499 if (BINFO_VTABLE_PATH_MARKED (b))
8501 BINFO_VTABLE_PATH_MARKED (b) = 1;
8503 /* Figure out where we can find this vbase offset. */
8504 delta = size_binop (MULT_EXPR,
8507 TYPE_SIZE_UNIT (vtable_entry_type)));
8508 if (vid->primary_vtbl_p)
8509 BINFO_VPTR_FIELD (b) = delta;
8511 if (binfo != TYPE_BINFO (t))
8512 /* The vbase offset had better be the same. */
8513 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
8515 /* The next vbase will come at a more negative offset. */
8516 vid->index = size_binop (MINUS_EXPR, vid->index,
8517 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8519 /* The initializer is the delta from BINFO to this virtual base.
8520 The vbase offsets go in reverse inheritance-graph order, and
8521 we are walking in inheritance graph order so these end up in
8523 delta = size_diffop_loc (input_location,
8524 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
8526 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE,
8527 fold_build1_loc (input_location, NOP_EXPR,
8528 vtable_entry_type, delta));
8532 /* Adds the initializers for the vcall offset entries in the vtable
8533 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
8537 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8539 /* We only need these entries if this base is a virtual base. We
8540 compute the indices -- but do not add to the vtable -- when
8541 building the main vtable for a class. */
8542 if (binfo == TYPE_BINFO (vid->derived)
8543 || (BINFO_VIRTUAL_P (binfo)
8544 /* If BINFO is RTTI_BINFO, then (since BINFO does not
8545 correspond to VID->DERIVED), we are building a primary
8546 construction virtual table. Since this is a primary
8547 virtual table, we do not need the vcall offsets for
8549 && binfo != vid->rtti_binfo))
8551 /* We need a vcall offset for each of the virtual functions in this
8552 vtable. For example:
8554 class A { virtual void f (); };
8555 class B1 : virtual public A { virtual void f (); };
8556 class B2 : virtual public A { virtual void f (); };
8557 class C: public B1, public B2 { virtual void f (); };
8559 A C object has a primary base of B1, which has a primary base of A. A
8560 C also has a secondary base of B2, which no longer has a primary base
8561 of A. So the B2-in-C construction vtable needs a secondary vtable for
8562 A, which will adjust the A* to a B2* to call f. We have no way of
8563 knowing what (or even whether) this offset will be when we define B2,
8564 so we store this "vcall offset" in the A sub-vtable and look it up in
8565 a "virtual thunk" for B2::f.
8567 We need entries for all the functions in our primary vtable and
8568 in our non-virtual bases' secondary vtables. */
8570 /* If we are just computing the vcall indices -- but do not need
8571 the actual entries -- not that. */
8572 if (!BINFO_VIRTUAL_P (binfo))
8573 vid->generate_vcall_entries = false;
8574 /* Now, walk through the non-virtual bases, adding vcall offsets. */
8575 add_vcall_offset_vtbl_entries_r (binfo, vid);
8579 /* Build vcall offsets, starting with those for BINFO. */
8582 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
8588 /* Don't walk into virtual bases -- except, of course, for the
8589 virtual base for which we are building vcall offsets. Any
8590 primary virtual base will have already had its offsets generated
8591 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8592 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
8595 /* If BINFO has a primary base, process it first. */
8596 primary_binfo = get_primary_binfo (binfo);
8598 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
8600 /* Add BINFO itself to the list. */
8601 add_vcall_offset_vtbl_entries_1 (binfo, vid);
8603 /* Scan the non-primary bases of BINFO. */
8604 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8605 if (base_binfo != primary_binfo)
8606 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
8609 /* Called from build_vcall_offset_vtbl_entries_r. */
8612 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
8614 /* Make entries for the rest of the virtuals. */
8615 if (abi_version_at_least (2))
8619 /* The ABI requires that the methods be processed in declaration
8620 order. G++ 3.2 used the order in the vtable. */
8621 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
8623 orig_fn = DECL_CHAIN (orig_fn))
8624 if (DECL_VINDEX (orig_fn))
8625 add_vcall_offset (orig_fn, binfo, vid);
8629 tree derived_virtuals;
8632 /* If BINFO is a primary base, the most derived class which has
8633 BINFO as a primary base; otherwise, just BINFO. */
8634 tree non_primary_binfo;
8636 /* We might be a primary base class. Go up the inheritance hierarchy
8637 until we find the most derived class of which we are a primary base:
8638 it is the BINFO_VIRTUALS there that we need to consider. */
8639 non_primary_binfo = binfo;
8640 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8644 /* If we have reached a virtual base, then it must be vid->vbase,
8645 because we ignore other virtual bases in
8646 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8647 base (possibly multi-level) of vid->binfo, or we wouldn't
8648 have called build_vcall_and_vbase_vtbl_entries for it. But it
8649 might be a lost primary, so just skip down to vid->binfo. */
8650 if (BINFO_VIRTUAL_P (non_primary_binfo))
8652 gcc_assert (non_primary_binfo == vid->vbase);
8653 non_primary_binfo = vid->binfo;
8657 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8658 if (get_primary_binfo (b) != non_primary_binfo)
8660 non_primary_binfo = b;
8663 if (vid->ctor_vtbl_p)
8664 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8665 where rtti_binfo is the most derived type. */
8667 = original_binfo (non_primary_binfo, vid->rtti_binfo);
8669 for (base_virtuals = BINFO_VIRTUALS (binfo),
8670 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
8671 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
8673 base_virtuals = TREE_CHAIN (base_virtuals),
8674 derived_virtuals = TREE_CHAIN (derived_virtuals),
8675 orig_virtuals = TREE_CHAIN (orig_virtuals))
8679 /* Find the declaration that originally caused this function to
8680 be present in BINFO_TYPE (binfo). */
8681 orig_fn = BV_FN (orig_virtuals);
8683 /* When processing BINFO, we only want to generate vcall slots for
8684 function slots introduced in BINFO. So don't try to generate
8685 one if the function isn't even defined in BINFO. */
8686 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
8689 add_vcall_offset (orig_fn, binfo, vid);
8694 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8697 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
8703 /* If there is already an entry for a function with the same
8704 signature as FN, then we do not need a second vcall offset.
8705 Check the list of functions already present in the derived
8707 FOR_EACH_VEC_ELT (tree, vid->fns, i, derived_entry)
8709 if (same_signature_p (derived_entry, orig_fn)
8710 /* We only use one vcall offset for virtual destructors,
8711 even though there are two virtual table entries. */
8712 || (DECL_DESTRUCTOR_P (derived_entry)
8713 && DECL_DESTRUCTOR_P (orig_fn)))
8717 /* If we are building these vcall offsets as part of building
8718 the vtable for the most derived class, remember the vcall
8720 if (vid->binfo == TYPE_BINFO (vid->derived))
8722 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
8723 CLASSTYPE_VCALL_INDICES (vid->derived),
8725 elt->purpose = orig_fn;
8726 elt->value = vid->index;
8729 /* The next vcall offset will be found at a more negative
8731 vid->index = size_binop (MINUS_EXPR, vid->index,
8732 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8734 /* Keep track of this function. */
8735 VEC_safe_push (tree, gc, vid->fns, orig_fn);
8737 if (vid->generate_vcall_entries)
8742 /* Find the overriding function. */
8743 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8744 if (fn == error_mark_node)
8745 vcall_offset = build_zero_cst (vtable_entry_type);
8748 base = TREE_VALUE (fn);
8750 /* The vbase we're working on is a primary base of
8751 vid->binfo. But it might be a lost primary, so its
8752 BINFO_OFFSET might be wrong, so we just use the
8753 BINFO_OFFSET from vid->binfo. */
8754 vcall_offset = size_diffop_loc (input_location,
8755 BINFO_OFFSET (base),
8756 BINFO_OFFSET (vid->binfo));
8757 vcall_offset = fold_build1_loc (input_location,
8758 NOP_EXPR, vtable_entry_type,
8761 /* Add the initializer to the vtable. */
8762 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, vcall_offset);
8766 /* Return vtbl initializers for the RTTI entries corresponding to the
8767 BINFO's vtable. The RTTI entries should indicate the object given
8768 by VID->rtti_binfo. */
8771 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8779 t = BINFO_TYPE (vid->rtti_binfo);
8781 /* To find the complete object, we will first convert to our most
8782 primary base, and then add the offset in the vtbl to that value. */
8784 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8785 && !BINFO_LOST_PRIMARY_P (b))
8789 primary_base = get_primary_binfo (b);
8790 gcc_assert (BINFO_PRIMARY_P (primary_base)
8791 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8794 offset = size_diffop_loc (input_location,
8795 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8797 /* The second entry is the address of the typeinfo object. */
8799 decl = build_address (get_tinfo_decl (t));
8801 decl = integer_zero_node;
8803 /* Convert the declaration to a type that can be stored in the
8805 init = build_nop (vfunc_ptr_type_node, decl);
8806 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8808 /* Add the offset-to-top entry. It comes earlier in the vtable than
8809 the typeinfo entry. Convert the offset to look like a
8810 function pointer, so that we can put it in the vtable. */
8811 init = build_nop (vfunc_ptr_type_node, offset);
8812 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8815 #include "gt-cp-class.h"