1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
39 #include "tree-dump.h"
41 /* The number of nested classes being processed. If we are not in the
42 scope of any class, this is zero. */
44 int current_class_depth;
46 /* In order to deal with nested classes, we keep a stack of classes.
47 The topmost entry is the innermost class, and is the entry at index
48 CURRENT_CLASS_DEPTH */
50 typedef struct class_stack_node {
51 /* The name of the class. */
54 /* The _TYPE node for the class. */
57 /* The access specifier pending for new declarations in the scope of
61 /* If were defining TYPE, the names used in this class. */
62 splay_tree names_used;
64 /* Nonzero if this class is no longer open, because of a call to
67 }* class_stack_node_t;
69 typedef struct vtbl_init_data_s
71 /* The base for which we're building initializers. */
73 /* The type of the most-derived type. */
75 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
76 unless ctor_vtbl_p is true. */
78 /* The negative-index vtable initializers built up so far. These
79 are in order from least negative index to most negative index. */
81 /* The last (i.e., most negative) entry in INITS. */
83 /* The binfo for the virtual base for which we're building
84 vcall offset initializers. */
86 /* The functions in vbase for which we have already provided vcall
89 /* The vtable index of the next vcall or vbase offset. */
91 /* Nonzero if we are building the initializer for the primary
94 /* Nonzero if we are building the initializer for a construction
97 /* True when adding vcall offset entries to the vtable. False when
98 merely computing the indices. */
99 bool generate_vcall_entries;
102 /* The type of a function passed to walk_subobject_offsets. */
103 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
105 /* The stack itself. This is a dynamically resized array. The
106 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
107 static int current_class_stack_size;
108 static class_stack_node_t current_class_stack;
110 /* The size of the largest empty class seen in this translation unit. */
111 static GTY (()) tree sizeof_biggest_empty_class;
113 /* An array of all local classes present in this translation unit, in
114 declaration order. */
115 VEC(tree,gc) *local_classes;
117 static tree get_vfield_name (tree);
118 static void finish_struct_anon (tree);
119 static tree get_vtable_name (tree);
120 static tree get_basefndecls (tree, tree);
121 static int build_primary_vtable (tree, tree);
122 static int build_secondary_vtable (tree);
123 static void finish_vtbls (tree);
124 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
125 static void finish_struct_bits (tree);
126 static int alter_access (tree, tree, tree);
127 static void handle_using_decl (tree, tree);
128 static tree dfs_modify_vtables (tree, void *);
129 static tree modify_all_vtables (tree, tree);
130 static void determine_primary_bases (tree);
131 static void finish_struct_methods (tree);
132 static void maybe_warn_about_overly_private_class (tree);
133 static int method_name_cmp (const void *, const void *);
134 static int resort_method_name_cmp (const void *, const void *);
135 static void add_implicitly_declared_members (tree, int, int);
136 static tree fixed_type_or_null (tree, int *, int *);
137 static tree build_simple_base_path (tree expr, tree binfo);
138 static tree build_vtbl_ref_1 (tree, tree);
139 static tree build_vtbl_initializer (tree, tree, tree, tree, int *);
140 static int count_fields (tree);
141 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
142 static bool check_bitfield_decl (tree);
143 static void check_field_decl (tree, tree, int *, int *, int *);
144 static void check_field_decls (tree, tree *, int *, int *);
145 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
146 static void build_base_fields (record_layout_info, splay_tree, tree *);
147 static void check_methods (tree);
148 static void remove_zero_width_bit_fields (tree);
149 static void check_bases (tree, int *, int *);
150 static void check_bases_and_members (tree);
151 static tree create_vtable_ptr (tree, tree *);
152 static void include_empty_classes (record_layout_info);
153 static void layout_class_type (tree, tree *);
154 static void propagate_binfo_offsets (tree, tree);
155 static void layout_virtual_bases (record_layout_info, splay_tree);
156 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
157 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
158 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
159 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
160 static void add_vcall_offset (tree, tree, vtbl_init_data *);
161 static void layout_vtable_decl (tree, int);
162 static tree dfs_find_final_overrider_pre (tree, void *);
163 static tree dfs_find_final_overrider_post (tree, void *);
164 static tree find_final_overrider (tree, tree, tree);
165 static int make_new_vtable (tree, tree);
166 static tree get_primary_binfo (tree);
167 static int maybe_indent_hierarchy (FILE *, int, int);
168 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
169 static void dump_class_hierarchy (tree);
170 static void dump_class_hierarchy_1 (FILE *, int, tree);
171 static void dump_array (FILE *, tree);
172 static void dump_vtable (tree, tree, tree);
173 static void dump_vtt (tree, tree);
174 static void dump_thunk (FILE *, int, tree);
175 static tree build_vtable (tree, tree, tree);
176 static void initialize_vtable (tree, tree);
177 static void layout_nonempty_base_or_field (record_layout_info,
178 tree, tree, splay_tree);
179 static tree end_of_class (tree, int);
180 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
181 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree);
182 static tree dfs_accumulate_vtbl_inits (tree, tree, tree, tree,
184 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
185 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
186 static void clone_constructors_and_destructors (tree);
187 static tree build_clone (tree, tree);
188 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
189 static void build_ctor_vtbl_group (tree, tree);
190 static void build_vtt (tree);
191 static tree binfo_ctor_vtable (tree);
192 static tree *build_vtt_inits (tree, tree, tree *, tree *);
193 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
194 static tree dfs_fixup_binfo_vtbls (tree, void *);
195 static int record_subobject_offset (tree, tree, splay_tree);
196 static int check_subobject_offset (tree, tree, splay_tree);
197 static int walk_subobject_offsets (tree, subobject_offset_fn,
198 tree, splay_tree, tree, int);
199 static void record_subobject_offsets (tree, tree, splay_tree, bool);
200 static int layout_conflict_p (tree, tree, splay_tree, int);
201 static int splay_tree_compare_integer_csts (splay_tree_key k1,
203 static void warn_about_ambiguous_bases (tree);
204 static bool type_requires_array_cookie (tree);
205 static bool contains_empty_class_p (tree);
206 static bool base_derived_from (tree, tree);
207 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
208 static tree end_of_base (tree);
209 static tree get_vcall_index (tree, tree);
211 /* Variables shared between class.c and call.c. */
213 #ifdef GATHER_STATISTICS
215 int n_vtable_entries = 0;
216 int n_vtable_searches = 0;
217 int n_vtable_elems = 0;
218 int n_convert_harshness = 0;
219 int n_compute_conversion_costs = 0;
220 int n_inner_fields_searched = 0;
223 /* Convert to or from a base subobject. EXPR is an expression of type
224 `A' or `A*', an expression of type `B' or `B*' is returned. To
225 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
226 the B base instance within A. To convert base A to derived B, CODE
227 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
228 In this latter case, A must not be a morally virtual base of B.
229 NONNULL is true if EXPR is known to be non-NULL (this is only
230 needed when EXPR is of pointer type). CV qualifiers are preserved
234 build_base_path (enum tree_code code,
239 tree v_binfo = NULL_TREE;
240 tree d_binfo = NULL_TREE;
244 tree null_test = NULL;
245 tree ptr_target_type;
247 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
248 bool has_empty = false;
251 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
252 return error_mark_node;
254 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
257 if (is_empty_class (BINFO_TYPE (probe)))
259 if (!v_binfo && BINFO_VIRTUAL_P (probe))
263 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
265 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
267 gcc_assert ((code == MINUS_EXPR
268 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
269 || (code == PLUS_EXPR
270 && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
272 if (binfo == d_binfo)
276 if (code == MINUS_EXPR && v_binfo)
278 error ("cannot convert from base %qT to derived type %qT via virtual base %qT",
279 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
280 return error_mark_node;
284 /* This must happen before the call to save_expr. */
285 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
287 offset = BINFO_OFFSET (binfo);
288 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
289 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
291 /* Do we need to look in the vtable for the real offset? */
292 virtual_access = (v_binfo && fixed_type_p <= 0);
294 /* Don't bother with the calculations inside sizeof; they'll ICE if the
295 source type is incomplete and the pointer value doesn't matter. */
296 if (cp_unevaluated_operand != 0)
298 expr = build_nop (build_pointer_type (target_type), expr);
300 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, NULL);
304 /* Do we need to check for a null pointer? */
305 if (want_pointer && !nonnull)
307 /* If we know the conversion will not actually change the value
308 of EXPR, then we can avoid testing the expression for NULL.
309 We have to avoid generating a COMPONENT_REF for a base class
310 field, because other parts of the compiler know that such
311 expressions are always non-NULL. */
312 if (!virtual_access && integer_zerop (offset))
315 /* TARGET_TYPE has been extracted from BINFO, and, is
316 therefore always cv-unqualified. Extract the
317 cv-qualifiers from EXPR so that the expression returned
318 matches the input. */
319 class_type = TREE_TYPE (TREE_TYPE (expr));
321 = cp_build_qualified_type (target_type,
322 cp_type_quals (class_type));
323 return build_nop (build_pointer_type (target_type), expr);
325 null_test = error_mark_node;
328 /* Protect against multiple evaluation if necessary. */
329 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
330 expr = save_expr (expr);
332 /* Now that we've saved expr, build the real null test. */
335 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
336 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
340 /* If this is a simple base reference, express it as a COMPONENT_REF. */
341 if (code == PLUS_EXPR && !virtual_access
342 /* We don't build base fields for empty bases, and they aren't very
343 interesting to the optimizers anyway. */
346 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
347 expr = build_simple_base_path (expr, binfo);
349 expr = build_address (expr);
350 target_type = TREE_TYPE (expr);
356 /* Going via virtual base V_BINFO. We need the static offset
357 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
358 V_BINFO. That offset is an entry in D_BINFO's vtable. */
361 if (fixed_type_p < 0 && in_base_initializer)
363 /* In a base member initializer, we cannot rely on the
364 vtable being set up. We have to indirect via the
368 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
369 t = build_pointer_type (t);
370 v_offset = convert (t, current_vtt_parm);
371 v_offset = cp_build_indirect_ref (v_offset, NULL,
372 tf_warning_or_error);
375 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, NULL,
376 tf_warning_or_error),
377 TREE_TYPE (TREE_TYPE (expr)));
379 v_offset = build2 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
380 v_offset, fold_convert (sizetype, BINFO_VPTR_FIELD (v_binfo)));
381 v_offset = build1 (NOP_EXPR,
382 build_pointer_type (ptrdiff_type_node),
384 v_offset = cp_build_indirect_ref (v_offset, NULL, tf_warning_or_error);
385 TREE_CONSTANT (v_offset) = 1;
387 offset = convert_to_integer (ptrdiff_type_node,
388 size_diffop_loc (input_location, offset,
389 BINFO_OFFSET (v_binfo)));
391 if (!integer_zerop (offset))
392 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
394 if (fixed_type_p < 0)
395 /* Negative fixed_type_p means this is a constructor or destructor;
396 virtual base layout is fixed in in-charge [cd]tors, but not in
398 offset = build3 (COND_EXPR, ptrdiff_type_node,
399 build2 (EQ_EXPR, boolean_type_node,
400 current_in_charge_parm, integer_zero_node),
402 convert_to_integer (ptrdiff_type_node,
403 BINFO_OFFSET (binfo)));
408 target_type = cp_build_qualified_type
409 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
410 ptr_target_type = build_pointer_type (target_type);
412 target_type = ptr_target_type;
414 expr = build1 (NOP_EXPR, ptr_target_type, expr);
416 if (!integer_zerop (offset))
418 offset = fold_convert (sizetype, offset);
419 if (code == MINUS_EXPR)
420 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
421 expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
427 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
431 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
432 fold_build1_loc (input_location, NOP_EXPR, target_type,
438 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
439 Perform a derived-to-base conversion by recursively building up a
440 sequence of COMPONENT_REFs to the appropriate base fields. */
443 build_simple_base_path (tree expr, tree binfo)
445 tree type = BINFO_TYPE (binfo);
446 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
449 if (d_binfo == NULL_TREE)
453 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
455 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
456 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
457 an lvalue in the front end; only _DECLs and _REFs are lvalues
459 temp = unary_complex_lvalue (ADDR_EXPR, expr);
461 expr = cp_build_indirect_ref (temp, NULL, tf_warning_or_error);
467 expr = build_simple_base_path (expr, d_binfo);
469 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
470 field; field = TREE_CHAIN (field))
471 /* Is this the base field created by build_base_field? */
472 if (TREE_CODE (field) == FIELD_DECL
473 && DECL_FIELD_IS_BASE (field)
474 && TREE_TYPE (field) == type)
476 /* We don't use build_class_member_access_expr here, as that
477 has unnecessary checks, and more importantly results in
478 recursive calls to dfs_walk_once. */
479 int type_quals = cp_type_quals (TREE_TYPE (expr));
481 expr = build3 (COMPONENT_REF,
482 cp_build_qualified_type (type, type_quals),
483 expr, field, NULL_TREE);
484 expr = fold_if_not_in_template (expr);
486 /* Mark the expression const or volatile, as appropriate.
487 Even though we've dealt with the type above, we still have
488 to mark the expression itself. */
489 if (type_quals & TYPE_QUAL_CONST)
490 TREE_READONLY (expr) = 1;
491 if (type_quals & TYPE_QUAL_VOLATILE)
492 TREE_THIS_VOLATILE (expr) = 1;
497 /* Didn't find the base field?!? */
501 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
502 type is a class type or a pointer to a class type. In the former
503 case, TYPE is also a class type; in the latter it is another
504 pointer type. If CHECK_ACCESS is true, an error message is emitted
505 if TYPE is inaccessible. If OBJECT has pointer type, the value is
506 assumed to be non-NULL. */
509 convert_to_base (tree object, tree type, bool check_access, bool nonnull)
514 if (TYPE_PTR_P (TREE_TYPE (object)))
516 object_type = TREE_TYPE (TREE_TYPE (object));
517 type = TREE_TYPE (type);
520 object_type = TREE_TYPE (object);
522 binfo = lookup_base (object_type, type,
523 check_access ? ba_check : ba_unique,
525 if (!binfo || binfo == error_mark_node)
526 return error_mark_node;
528 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
531 /* EXPR is an expression with unqualified class type. BASE is a base
532 binfo of that class type. Returns EXPR, converted to the BASE
533 type. This function assumes that EXPR is the most derived class;
534 therefore virtual bases can be found at their static offsets. */
537 convert_to_base_statically (tree expr, tree base)
541 expr_type = TREE_TYPE (expr);
542 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
546 pointer_type = build_pointer_type (expr_type);
548 /* We use fold_build2 and fold_convert below to simplify the trees
549 provided to the optimizers. It is not safe to call these functions
550 when processing a template because they do not handle C++-specific
552 gcc_assert (!processing_template_decl);
553 expr = cp_build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1,
554 tf_warning_or_error);
555 if (!integer_zerop (BINFO_OFFSET (base)))
556 expr = fold_build2_loc (input_location,
557 POINTER_PLUS_EXPR, pointer_type, expr,
558 fold_convert (sizetype, BINFO_OFFSET (base)));
559 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
560 expr = build_fold_indirect_ref_loc (input_location, expr);
568 build_vfield_ref (tree datum, tree type)
570 tree vfield, vcontext;
572 if (datum == error_mark_node)
573 return error_mark_node;
575 /* First, convert to the requested type. */
576 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
577 datum = convert_to_base (datum, type, /*check_access=*/false,
580 /* Second, the requested type may not be the owner of its own vptr.
581 If not, convert to the base class that owns it. We cannot use
582 convert_to_base here, because VCONTEXT may appear more than once
583 in the inheritance hierarchy of TYPE, and thus direct conversion
584 between the types may be ambiguous. Following the path back up
585 one step at a time via primary bases avoids the problem. */
586 vfield = TYPE_VFIELD (type);
587 vcontext = DECL_CONTEXT (vfield);
588 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
590 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
591 type = TREE_TYPE (datum);
594 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
597 /* Given an object INSTANCE, return an expression which yields the
598 vtable element corresponding to INDEX. There are many special
599 cases for INSTANCE which we take care of here, mainly to avoid
600 creating extra tree nodes when we don't have to. */
603 build_vtbl_ref_1 (tree instance, tree idx)
606 tree vtbl = NULL_TREE;
608 /* Try to figure out what a reference refers to, and
609 access its virtual function table directly. */
612 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
614 tree basetype = non_reference (TREE_TYPE (instance));
616 if (fixed_type && !cdtorp)
618 tree binfo = lookup_base (fixed_type, basetype,
619 ba_unique | ba_quiet, NULL);
621 vtbl = unshare_expr (BINFO_VTABLE (binfo));
625 vtbl = build_vfield_ref (instance, basetype);
627 aref = build_array_ref (input_location, vtbl, idx);
628 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
634 build_vtbl_ref (tree instance, tree idx)
636 tree aref = build_vtbl_ref_1 (instance, idx);
641 /* Given a stable object pointer INSTANCE_PTR, return an expression which
642 yields a function pointer corresponding to vtable element INDEX. */
645 build_vfn_ref (tree instance_ptr, tree idx)
649 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, 0,
650 tf_warning_or_error),
653 /* When using function descriptors, the address of the
654 vtable entry is treated as a function pointer. */
655 if (TARGET_VTABLE_USES_DESCRIPTORS)
656 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
657 cp_build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1,
658 tf_warning_or_error));
660 /* Remember this as a method reference, for later devirtualization. */
661 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
666 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
667 for the given TYPE. */
670 get_vtable_name (tree type)
672 return mangle_vtbl_for_type (type);
675 /* DECL is an entity associated with TYPE, like a virtual table or an
676 implicitly generated constructor. Determine whether or not DECL
677 should have external or internal linkage at the object file
678 level. This routine does not deal with COMDAT linkage and other
679 similar complexities; it simply sets TREE_PUBLIC if it possible for
680 entities in other translation units to contain copies of DECL, in
684 set_linkage_according_to_type (tree type, tree decl)
686 /* If TYPE involves a local class in a function with internal
687 linkage, then DECL should have internal linkage too. Other local
688 classes have no linkage -- but if their containing functions
689 have external linkage, it makes sense for DECL to have external
690 linkage too. That will allow template definitions to be merged,
692 if (no_linkage_check (type, /*relaxed_p=*/true))
694 TREE_PUBLIC (decl) = 0;
695 DECL_INTERFACE_KNOWN (decl) = 1;
698 TREE_PUBLIC (decl) = 1;
701 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
702 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
703 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
706 build_vtable (tree class_type, tree name, tree vtable_type)
710 decl = build_lang_decl (VAR_DECL, name, vtable_type);
711 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
712 now to avoid confusion in mangle_decl. */
713 SET_DECL_ASSEMBLER_NAME (decl, name);
714 DECL_CONTEXT (decl) = class_type;
715 DECL_ARTIFICIAL (decl) = 1;
716 TREE_STATIC (decl) = 1;
717 TREE_READONLY (decl) = 1;
718 DECL_VIRTUAL_P (decl) = 1;
719 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
720 DECL_VTABLE_OR_VTT_P (decl) = 1;
721 /* At one time the vtable info was grabbed 2 words at a time. This
722 fails on sparc unless you have 8-byte alignment. (tiemann) */
723 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
725 set_linkage_according_to_type (class_type, decl);
726 /* The vtable has not been defined -- yet. */
727 DECL_EXTERNAL (decl) = 1;
728 DECL_NOT_REALLY_EXTERN (decl) = 1;
730 /* Mark the VAR_DECL node representing the vtable itself as a
731 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
732 is rather important that such things be ignored because any
733 effort to actually generate DWARF for them will run into
734 trouble when/if we encounter code like:
737 struct S { virtual void member (); };
739 because the artificial declaration of the vtable itself (as
740 manufactured by the g++ front end) will say that the vtable is
741 a static member of `S' but only *after* the debug output for
742 the definition of `S' has already been output. This causes
743 grief because the DWARF entry for the definition of the vtable
744 will try to refer back to an earlier *declaration* of the
745 vtable as a static member of `S' and there won't be one. We
746 might be able to arrange to have the "vtable static member"
747 attached to the member list for `S' before the debug info for
748 `S' get written (which would solve the problem) but that would
749 require more intrusive changes to the g++ front end. */
750 DECL_IGNORED_P (decl) = 1;
755 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
756 or even complete. If this does not exist, create it. If COMPLETE is
757 nonzero, then complete the definition of it -- that will render it
758 impossible to actually build the vtable, but is useful to get at those
759 which are known to exist in the runtime. */
762 get_vtable_decl (tree type, int complete)
766 if (CLASSTYPE_VTABLES (type))
767 return CLASSTYPE_VTABLES (type);
769 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
770 CLASSTYPE_VTABLES (type) = decl;
774 DECL_EXTERNAL (decl) = 1;
775 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
781 /* Build the primary virtual function table for TYPE. If BINFO is
782 non-NULL, build the vtable starting with the initial approximation
783 that it is the same as the one which is the head of the association
784 list. Returns a nonzero value if a new vtable is actually
788 build_primary_vtable (tree binfo, tree type)
793 decl = get_vtable_decl (type, /*complete=*/0);
797 if (BINFO_NEW_VTABLE_MARKED (binfo))
798 /* We have already created a vtable for this base, so there's
799 no need to do it again. */
802 virtuals = copy_list (BINFO_VIRTUALS (binfo));
803 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
804 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
805 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
809 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
810 virtuals = NULL_TREE;
813 #ifdef GATHER_STATISTICS
815 n_vtable_elems += list_length (virtuals);
818 /* Initialize the association list for this type, based
819 on our first approximation. */
820 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
821 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
822 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
826 /* Give BINFO a new virtual function table which is initialized
827 with a skeleton-copy of its original initialization. The only
828 entry that changes is the `delta' entry, so we can really
829 share a lot of structure.
831 FOR_TYPE is the most derived type which caused this table to
834 Returns nonzero if we haven't met BINFO before.
836 The order in which vtables are built (by calling this function) for
837 an object must remain the same, otherwise a binary incompatibility
841 build_secondary_vtable (tree binfo)
843 if (BINFO_NEW_VTABLE_MARKED (binfo))
844 /* We already created a vtable for this base. There's no need to
848 /* Remember that we've created a vtable for this BINFO, so that we
849 don't try to do so again. */
850 SET_BINFO_NEW_VTABLE_MARKED (binfo);
852 /* Make fresh virtual list, so we can smash it later. */
853 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
855 /* Secondary vtables are laid out as part of the same structure as
856 the primary vtable. */
857 BINFO_VTABLE (binfo) = NULL_TREE;
861 /* Create a new vtable for BINFO which is the hierarchy dominated by
862 T. Return nonzero if we actually created a new vtable. */
865 make_new_vtable (tree t, tree binfo)
867 if (binfo == TYPE_BINFO (t))
868 /* In this case, it is *type*'s vtable we are modifying. We start
869 with the approximation that its vtable is that of the
870 immediate base class. */
871 return build_primary_vtable (binfo, t);
873 /* This is our very own copy of `basetype' to play with. Later,
874 we will fill in all the virtual functions that override the
875 virtual functions in these base classes which are not defined
876 by the current type. */
877 return build_secondary_vtable (binfo);
880 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
881 (which is in the hierarchy dominated by T) list FNDECL as its
882 BV_FN. DELTA is the required constant adjustment from the `this'
883 pointer where the vtable entry appears to the `this' required when
884 the function is actually called. */
887 modify_vtable_entry (tree t,
897 if (fndecl != BV_FN (v)
898 || !tree_int_cst_equal (delta, BV_DELTA (v)))
900 /* We need a new vtable for BINFO. */
901 if (make_new_vtable (t, binfo))
903 /* If we really did make a new vtable, we also made a copy
904 of the BINFO_VIRTUALS list. Now, we have to find the
905 corresponding entry in that list. */
906 *virtuals = BINFO_VIRTUALS (binfo);
907 while (BV_FN (*virtuals) != BV_FN (v))
908 *virtuals = TREE_CHAIN (*virtuals);
912 BV_DELTA (v) = delta;
913 BV_VCALL_INDEX (v) = NULL_TREE;
919 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
920 the USING_DECL naming METHOD. Returns true if the method could be
921 added to the method vec. */
924 add_method (tree type, tree method, tree using_decl)
928 bool template_conv_p = false;
930 VEC(tree,gc) *method_vec;
932 bool insert_p = false;
936 if (method == error_mark_node)
939 complete_p = COMPLETE_TYPE_P (type);
940 conv_p = DECL_CONV_FN_P (method);
942 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
943 && DECL_TEMPLATE_CONV_FN_P (method));
945 method_vec = CLASSTYPE_METHOD_VEC (type);
948 /* Make a new method vector. We start with 8 entries. We must
949 allocate at least two (for constructors and destructors), and
950 we're going to end up with an assignment operator at some
952 method_vec = VEC_alloc (tree, gc, 8);
953 /* Create slots for constructors and destructors. */
954 VEC_quick_push (tree, method_vec, NULL_TREE);
955 VEC_quick_push (tree, method_vec, NULL_TREE);
956 CLASSTYPE_METHOD_VEC (type) = method_vec;
959 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
960 grok_special_member_properties (method);
962 /* Constructors and destructors go in special slots. */
963 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
964 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
965 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
967 slot = CLASSTYPE_DESTRUCTOR_SLOT;
969 if (TYPE_FOR_JAVA (type))
971 if (!DECL_ARTIFICIAL (method))
972 error ("Java class %qT cannot have a destructor", type);
973 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
974 error ("Java class %qT cannot have an implicit non-trivial "
984 /* See if we already have an entry with this name. */
985 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
986 VEC_iterate (tree, method_vec, slot, m);
992 if (TREE_CODE (m) == TEMPLATE_DECL
993 && DECL_TEMPLATE_CONV_FN_P (m))
997 if (conv_p && !DECL_CONV_FN_P (m))
999 if (DECL_NAME (m) == DECL_NAME (method))
1005 && !DECL_CONV_FN_P (m)
1006 && DECL_NAME (m) > DECL_NAME (method))
1010 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1012 /* Check to see if we've already got this method. */
1013 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1015 tree fn = OVL_CURRENT (fns);
1021 if (TREE_CODE (fn) != TREE_CODE (method))
1024 /* [over.load] Member function declarations with the
1025 same name and the same parameter types cannot be
1026 overloaded if any of them is a static member
1027 function declaration.
1029 [namespace.udecl] When a using-declaration brings names
1030 from a base class into a derived class scope, member
1031 functions in the derived class override and/or hide member
1032 functions with the same name and parameter types in a base
1033 class (rather than conflicting). */
1034 fn_type = TREE_TYPE (fn);
1035 method_type = TREE_TYPE (method);
1036 parms1 = TYPE_ARG_TYPES (fn_type);
1037 parms2 = TYPE_ARG_TYPES (method_type);
1039 /* Compare the quals on the 'this' parm. Don't compare
1040 the whole types, as used functions are treated as
1041 coming from the using class in overload resolution. */
1042 if (! DECL_STATIC_FUNCTION_P (fn)
1043 && ! DECL_STATIC_FUNCTION_P (method)
1044 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1045 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1046 && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
1047 != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
1050 /* For templates, the return type and template parameters
1051 must be identical. */
1052 if (TREE_CODE (fn) == TEMPLATE_DECL
1053 && (!same_type_p (TREE_TYPE (fn_type),
1054 TREE_TYPE (method_type))
1055 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1056 DECL_TEMPLATE_PARMS (method))))
1059 if (! DECL_STATIC_FUNCTION_P (fn))
1060 parms1 = TREE_CHAIN (parms1);
1061 if (! DECL_STATIC_FUNCTION_P (method))
1062 parms2 = TREE_CHAIN (parms2);
1064 if (compparms (parms1, parms2)
1065 && (!DECL_CONV_FN_P (fn)
1066 || same_type_p (TREE_TYPE (fn_type),
1067 TREE_TYPE (method_type))))
1071 if (DECL_CONTEXT (fn) == type)
1072 /* Defer to the local function. */
1074 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1075 error ("repeated using declaration %q+D", using_decl);
1077 error ("using declaration %q+D conflicts with a previous using declaration",
1082 error ("%q+#D cannot be overloaded", method);
1083 error ("with %q+#D", fn);
1086 /* We don't call duplicate_decls here to merge the
1087 declarations because that will confuse things if the
1088 methods have inline definitions. In particular, we
1089 will crash while processing the definitions. */
1094 /* A class should never have more than one destructor. */
1095 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1098 /* Add the new binding. */
1099 overload = build_overload (method, current_fns);
1102 TYPE_HAS_CONVERSION (type) = 1;
1103 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1104 push_class_level_binding (DECL_NAME (method), overload);
1110 /* We only expect to add few methods in the COMPLETE_P case, so
1111 just make room for one more method in that case. */
1113 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1115 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1117 CLASSTYPE_METHOD_VEC (type) = method_vec;
1118 if (slot == VEC_length (tree, method_vec))
1119 VEC_quick_push (tree, method_vec, overload);
1121 VEC_quick_insert (tree, method_vec, slot, overload);
1124 /* Replace the current slot. */
1125 VEC_replace (tree, method_vec, slot, overload);
1129 /* Subroutines of finish_struct. */
1131 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1132 legit, otherwise return 0. */
1135 alter_access (tree t, tree fdecl, tree access)
1139 if (!DECL_LANG_SPECIFIC (fdecl))
1140 retrofit_lang_decl (fdecl);
1142 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1144 elem = purpose_member (t, DECL_ACCESS (fdecl));
1147 if (TREE_VALUE (elem) != access)
1149 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1150 error ("conflicting access specifications for method"
1151 " %q+D, ignored", TREE_TYPE (fdecl));
1153 error ("conflicting access specifications for field %qE, ignored",
1158 /* They're changing the access to the same thing they changed
1159 it to before. That's OK. */
1165 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1166 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1172 /* Process the USING_DECL, which is a member of T. */
1175 handle_using_decl (tree using_decl, tree t)
1177 tree decl = USING_DECL_DECLS (using_decl);
1178 tree name = DECL_NAME (using_decl);
1180 = TREE_PRIVATE (using_decl) ? access_private_node
1181 : TREE_PROTECTED (using_decl) ? access_protected_node
1182 : access_public_node;
1183 tree flist = NULL_TREE;
1186 gcc_assert (!processing_template_decl && decl);
1188 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1191 if (is_overloaded_fn (old_value))
1192 old_value = OVL_CURRENT (old_value);
1194 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1197 old_value = NULL_TREE;
1200 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1202 if (is_overloaded_fn (decl))
1207 else if (is_overloaded_fn (old_value))
1210 /* It's OK to use functions from a base when there are functions with
1211 the same name already present in the current class. */;
1214 error ("%q+D invalid in %q#T", using_decl, t);
1215 error (" because of local method %q+#D with same name",
1216 OVL_CURRENT (old_value));
1220 else if (!DECL_ARTIFICIAL (old_value))
1222 error ("%q+D invalid in %q#T", using_decl, t);
1223 error (" because of local member %q+#D with same name", old_value);
1227 /* Make type T see field decl FDECL with access ACCESS. */
1229 for (; flist; flist = OVL_NEXT (flist))
1231 add_method (t, OVL_CURRENT (flist), using_decl);
1232 alter_access (t, OVL_CURRENT (flist), access);
1235 alter_access (t, decl, access);
1238 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1239 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1240 properties of the bases. */
1243 check_bases (tree t,
1244 int* cant_have_const_ctor_p,
1245 int* no_const_asn_ref_p)
1248 int seen_non_virtual_nearly_empty_base_p;
1251 tree field = NULL_TREE;
1253 seen_non_virtual_nearly_empty_base_p = 0;
1255 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1256 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1257 if (TREE_CODE (field) == FIELD_DECL)
1260 for (binfo = TYPE_BINFO (t), i = 0;
1261 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1263 tree basetype = TREE_TYPE (base_binfo);
1265 gcc_assert (COMPLETE_TYPE_P (basetype));
1267 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1268 here because the case of virtual functions but non-virtual
1269 dtor is handled in finish_struct_1. */
1270 if (!TYPE_POLYMORPHIC_P (basetype))
1271 warning (OPT_Weffc__,
1272 "base class %q#T has a non-virtual destructor", basetype);
1274 /* If the base class doesn't have copy constructors or
1275 assignment operators that take const references, then the
1276 derived class cannot have such a member automatically
1278 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1279 *cant_have_const_ctor_p = 1;
1280 if (TYPE_HAS_ASSIGN_REF (basetype)
1281 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1282 *no_const_asn_ref_p = 1;
1284 if (BINFO_VIRTUAL_P (base_binfo))
1285 /* A virtual base does not effect nearly emptiness. */
1287 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1289 if (seen_non_virtual_nearly_empty_base_p)
1290 /* And if there is more than one nearly empty base, then the
1291 derived class is not nearly empty either. */
1292 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1294 /* Remember we've seen one. */
1295 seen_non_virtual_nearly_empty_base_p = 1;
1297 else if (!is_empty_class (basetype))
1298 /* If the base class is not empty or nearly empty, then this
1299 class cannot be nearly empty. */
1300 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1302 /* A lot of properties from the bases also apply to the derived
1304 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1305 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1306 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1307 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1308 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1309 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1310 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1311 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1312 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1313 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (basetype);
1315 /* A standard-layout class is a class that:
1317 * has no non-standard-layout base classes, */
1318 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1319 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1322 /* ...has no base classes of the same type as the first non-static
1324 if (field && DECL_CONTEXT (field) == t
1325 && (same_type_ignoring_top_level_qualifiers_p
1326 (TREE_TYPE (field), basetype)))
1327 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1329 /* ...either has no non-static data members in the most-derived
1330 class and at most one base class with non-static data
1331 members, or has no base classes with non-static data
1333 for (basefield = TYPE_FIELDS (basetype); basefield;
1334 basefield = TREE_CHAIN (basefield))
1335 if (TREE_CODE (basefield) == FIELD_DECL)
1338 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1347 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1348 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1349 that have had a nearly-empty virtual primary base stolen by some
1350 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1354 determine_primary_bases (tree t)
1357 tree primary = NULL_TREE;
1358 tree type_binfo = TYPE_BINFO (t);
1361 /* Determine the primary bases of our bases. */
1362 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1363 base_binfo = TREE_CHAIN (base_binfo))
1365 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1367 /* See if we're the non-virtual primary of our inheritance
1369 if (!BINFO_VIRTUAL_P (base_binfo))
1371 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1372 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1375 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1376 BINFO_TYPE (parent_primary)))
1377 /* We are the primary binfo. */
1378 BINFO_PRIMARY_P (base_binfo) = 1;
1380 /* Determine if we have a virtual primary base, and mark it so.
1382 if (primary && BINFO_VIRTUAL_P (primary))
1384 tree this_primary = copied_binfo (primary, base_binfo);
1386 if (BINFO_PRIMARY_P (this_primary))
1387 /* Someone already claimed this base. */
1388 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1393 BINFO_PRIMARY_P (this_primary) = 1;
1394 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1396 /* A virtual binfo might have been copied from within
1397 another hierarchy. As we're about to use it as a
1398 primary base, make sure the offsets match. */
1399 delta = size_diffop_loc (input_location,
1401 BINFO_OFFSET (base_binfo)),
1403 BINFO_OFFSET (this_primary)));
1405 propagate_binfo_offsets (this_primary, delta);
1410 /* First look for a dynamic direct non-virtual base. */
1411 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1413 tree basetype = BINFO_TYPE (base_binfo);
1415 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1417 primary = base_binfo;
1422 /* A "nearly-empty" virtual base class can be the primary base
1423 class, if no non-virtual polymorphic base can be found. Look for
1424 a nearly-empty virtual dynamic base that is not already a primary
1425 base of something in the hierarchy. If there is no such base,
1426 just pick the first nearly-empty virtual base. */
1428 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1429 base_binfo = TREE_CHAIN (base_binfo))
1430 if (BINFO_VIRTUAL_P (base_binfo)
1431 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1433 if (!BINFO_PRIMARY_P (base_binfo))
1435 /* Found one that is not primary. */
1436 primary = base_binfo;
1440 /* Remember the first candidate. */
1441 primary = base_binfo;
1445 /* If we've got a primary base, use it. */
1448 tree basetype = BINFO_TYPE (primary);
1450 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1451 if (BINFO_PRIMARY_P (primary))
1452 /* We are stealing a primary base. */
1453 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1454 BINFO_PRIMARY_P (primary) = 1;
1455 if (BINFO_VIRTUAL_P (primary))
1459 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1460 /* A virtual binfo might have been copied from within
1461 another hierarchy. As we're about to use it as a primary
1462 base, make sure the offsets match. */
1463 delta = size_diffop_loc (input_location, ssize_int (0),
1464 convert (ssizetype, BINFO_OFFSET (primary)));
1466 propagate_binfo_offsets (primary, delta);
1469 primary = TYPE_BINFO (basetype);
1471 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1472 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1473 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1477 /* Update the variant types of T. */
1480 fixup_type_variants (tree t)
1487 for (variants = TYPE_NEXT_VARIANT (t);
1489 variants = TYPE_NEXT_VARIANT (variants))
1491 /* These fields are in the _TYPE part of the node, not in
1492 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1493 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1494 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1495 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1496 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1498 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1500 TYPE_BINFO (variants) = TYPE_BINFO (t);
1502 /* Copy whatever these are holding today. */
1503 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1504 TYPE_METHODS (variants) = TYPE_METHODS (t);
1505 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1507 /* All variants of a class have the same attributes. */
1508 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1513 /* Set memoizing fields and bits of T (and its variants) for later
1517 finish_struct_bits (tree t)
1519 /* Fix up variants (if any). */
1520 fixup_type_variants (t);
1522 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1523 /* For a class w/o baseclasses, 'finish_struct' has set
1524 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1525 Similarly for a class whose base classes do not have vtables.
1526 When neither of these is true, we might have removed abstract
1527 virtuals (by providing a definition), added some (by declaring
1528 new ones), or redeclared ones from a base class. We need to
1529 recalculate what's really an abstract virtual at this point (by
1530 looking in the vtables). */
1531 get_pure_virtuals (t);
1533 /* If this type has a copy constructor or a destructor, force its
1534 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1535 nonzero. This will cause it to be passed by invisible reference
1536 and prevent it from being returned in a register. */
1537 if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1540 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1541 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1543 SET_TYPE_MODE (variants, BLKmode);
1544 TREE_ADDRESSABLE (variants) = 1;
1549 /* Issue warnings about T having private constructors, but no friends,
1552 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1553 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1554 non-private static member functions. */
1557 maybe_warn_about_overly_private_class (tree t)
1559 int has_member_fn = 0;
1560 int has_nonprivate_method = 0;
1563 if (!warn_ctor_dtor_privacy
1564 /* If the class has friends, those entities might create and
1565 access instances, so we should not warn. */
1566 || (CLASSTYPE_FRIEND_CLASSES (t)
1567 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1568 /* We will have warned when the template was declared; there's
1569 no need to warn on every instantiation. */
1570 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1571 /* There's no reason to even consider warning about this
1575 /* We only issue one warning, if more than one applies, because
1576 otherwise, on code like:
1579 // Oops - forgot `public:'
1585 we warn several times about essentially the same problem. */
1587 /* Check to see if all (non-constructor, non-destructor) member
1588 functions are private. (Since there are no friends or
1589 non-private statics, we can't ever call any of the private member
1591 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1592 /* We're not interested in compiler-generated methods; they don't
1593 provide any way to call private members. */
1594 if (!DECL_ARTIFICIAL (fn))
1596 if (!TREE_PRIVATE (fn))
1598 if (DECL_STATIC_FUNCTION_P (fn))
1599 /* A non-private static member function is just like a
1600 friend; it can create and invoke private member
1601 functions, and be accessed without a class
1605 has_nonprivate_method = 1;
1606 /* Keep searching for a static member function. */
1608 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1612 if (!has_nonprivate_method && has_member_fn)
1614 /* There are no non-private methods, and there's at least one
1615 private member function that isn't a constructor or
1616 destructor. (If all the private members are
1617 constructors/destructors we want to use the code below that
1618 issues error messages specifically referring to
1619 constructors/destructors.) */
1621 tree binfo = TYPE_BINFO (t);
1623 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1624 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1626 has_nonprivate_method = 1;
1629 if (!has_nonprivate_method)
1631 warning (OPT_Wctor_dtor_privacy,
1632 "all member functions in class %qT are private", t);
1637 /* Even if some of the member functions are non-private, the class
1638 won't be useful for much if all the constructors or destructors
1639 are private: such an object can never be created or destroyed. */
1640 fn = CLASSTYPE_DESTRUCTORS (t);
1641 if (fn && TREE_PRIVATE (fn))
1643 warning (OPT_Wctor_dtor_privacy,
1644 "%q#T only defines a private destructor and has no friends",
1649 /* Warn about classes that have private constructors and no friends. */
1650 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1651 /* Implicitly generated constructors are always public. */
1652 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1653 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1655 int nonprivate_ctor = 0;
1657 /* If a non-template class does not define a copy
1658 constructor, one is defined for it, enabling it to avoid
1659 this warning. For a template class, this does not
1660 happen, and so we would normally get a warning on:
1662 template <class T> class C { private: C(); };
1664 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1665 complete non-template or fully instantiated classes have this
1667 if (!TYPE_HAS_INIT_REF (t))
1668 nonprivate_ctor = 1;
1670 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1672 tree ctor = OVL_CURRENT (fn);
1673 /* Ideally, we wouldn't count copy constructors (or, in
1674 fact, any constructor that takes an argument of the
1675 class type as a parameter) because such things cannot
1676 be used to construct an instance of the class unless
1677 you already have one. But, for now at least, we're
1679 if (! TREE_PRIVATE (ctor))
1681 nonprivate_ctor = 1;
1686 if (nonprivate_ctor == 0)
1688 warning (OPT_Wctor_dtor_privacy,
1689 "%q#T only defines private constructors and has no friends",
1697 gt_pointer_operator new_value;
1701 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1704 method_name_cmp (const void* m1_p, const void* m2_p)
1706 const tree *const m1 = (const tree *) m1_p;
1707 const tree *const m2 = (const tree *) m2_p;
1709 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1711 if (*m1 == NULL_TREE)
1713 if (*m2 == NULL_TREE)
1715 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1720 /* This routine compares two fields like method_name_cmp but using the
1721 pointer operator in resort_field_decl_data. */
1724 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1726 const tree *const m1 = (const tree *) m1_p;
1727 const tree *const m2 = (const tree *) m2_p;
1728 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1730 if (*m1 == NULL_TREE)
1732 if (*m2 == NULL_TREE)
1735 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1736 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1737 resort_data.new_value (&d1, resort_data.cookie);
1738 resort_data.new_value (&d2, resort_data.cookie);
1745 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1748 resort_type_method_vec (void* obj,
1749 void* orig_obj ATTRIBUTE_UNUSED ,
1750 gt_pointer_operator new_value,
1753 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1754 int len = VEC_length (tree, method_vec);
1758 /* The type conversion ops have to live at the front of the vec, so we
1760 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1761 VEC_iterate (tree, method_vec, slot, fn);
1763 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1768 resort_data.new_value = new_value;
1769 resort_data.cookie = cookie;
1770 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1771 resort_method_name_cmp);
1775 /* Warn about duplicate methods in fn_fields.
1777 Sort methods that are not special (i.e., constructors, destructors,
1778 and type conversion operators) so that we can find them faster in
1782 finish_struct_methods (tree t)
1785 VEC(tree,gc) *method_vec;
1788 method_vec = CLASSTYPE_METHOD_VEC (t);
1792 len = VEC_length (tree, method_vec);
1794 /* Clear DECL_IN_AGGR_P for all functions. */
1795 for (fn_fields = TYPE_METHODS (t); fn_fields;
1796 fn_fields = TREE_CHAIN (fn_fields))
1797 DECL_IN_AGGR_P (fn_fields) = 0;
1799 /* Issue warnings about private constructors and such. If there are
1800 no methods, then some public defaults are generated. */
1801 maybe_warn_about_overly_private_class (t);
1803 /* The type conversion ops have to live at the front of the vec, so we
1805 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1806 VEC_iterate (tree, method_vec, slot, fn_fields);
1808 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1811 qsort (VEC_address (tree, method_vec) + slot,
1812 len-slot, sizeof (tree), method_name_cmp);
1815 /* Make BINFO's vtable have N entries, including RTTI entries,
1816 vbase and vcall offsets, etc. Set its type and call the back end
1820 layout_vtable_decl (tree binfo, int n)
1825 atype = build_cplus_array_type (vtable_entry_type,
1826 build_index_type (size_int (n - 1)));
1827 layout_type (atype);
1829 /* We may have to grow the vtable. */
1830 vtable = get_vtbl_decl_for_binfo (binfo);
1831 if (!same_type_p (TREE_TYPE (vtable), atype))
1833 TREE_TYPE (vtable) = atype;
1834 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1835 layout_decl (vtable, 0);
1839 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1840 have the same signature. */
1843 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1845 /* One destructor overrides another if they are the same kind of
1847 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1848 && special_function_p (base_fndecl) == special_function_p (fndecl))
1850 /* But a non-destructor never overrides a destructor, nor vice
1851 versa, nor do different kinds of destructors override
1852 one-another. For example, a complete object destructor does not
1853 override a deleting destructor. */
1854 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1857 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1858 || (DECL_CONV_FN_P (fndecl)
1859 && DECL_CONV_FN_P (base_fndecl)
1860 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1861 DECL_CONV_FN_TYPE (base_fndecl))))
1863 tree types, base_types;
1864 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1865 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1866 if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1867 == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1868 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1874 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1878 base_derived_from (tree derived, tree base)
1882 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1884 if (probe == derived)
1886 else if (BINFO_VIRTUAL_P (probe))
1887 /* If we meet a virtual base, we can't follow the inheritance
1888 any more. See if the complete type of DERIVED contains
1889 such a virtual base. */
1890 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1896 typedef struct find_final_overrider_data_s {
1897 /* The function for which we are trying to find a final overrider. */
1899 /* The base class in which the function was declared. */
1900 tree declaring_base;
1901 /* The candidate overriders. */
1903 /* Path to most derived. */
1904 VEC(tree,heap) *path;
1905 } find_final_overrider_data;
1907 /* Add the overrider along the current path to FFOD->CANDIDATES.
1908 Returns true if an overrider was found; false otherwise. */
1911 dfs_find_final_overrider_1 (tree binfo,
1912 find_final_overrider_data *ffod,
1917 /* If BINFO is not the most derived type, try a more derived class.
1918 A definition there will overrider a definition here. */
1922 if (dfs_find_final_overrider_1
1923 (VEC_index (tree, ffod->path, depth), ffod, depth))
1927 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1930 tree *candidate = &ffod->candidates;
1932 /* Remove any candidates overridden by this new function. */
1935 /* If *CANDIDATE overrides METHOD, then METHOD
1936 cannot override anything else on the list. */
1937 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1939 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1940 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1941 *candidate = TREE_CHAIN (*candidate);
1943 candidate = &TREE_CHAIN (*candidate);
1946 /* Add the new function. */
1947 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1954 /* Called from find_final_overrider via dfs_walk. */
1957 dfs_find_final_overrider_pre (tree binfo, void *data)
1959 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1961 if (binfo == ffod->declaring_base)
1962 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1963 VEC_safe_push (tree, heap, ffod->path, binfo);
1969 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1971 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1972 VEC_pop (tree, ffod->path);
1977 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1978 FN and whose TREE_VALUE is the binfo for the base where the
1979 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1980 DERIVED) is the base object in which FN is declared. */
1983 find_final_overrider (tree derived, tree binfo, tree fn)
1985 find_final_overrider_data ffod;
1987 /* Getting this right is a little tricky. This is valid:
1989 struct S { virtual void f (); };
1990 struct T { virtual void f (); };
1991 struct U : public S, public T { };
1993 even though calling `f' in `U' is ambiguous. But,
1995 struct R { virtual void f(); };
1996 struct S : virtual public R { virtual void f (); };
1997 struct T : virtual public R { virtual void f (); };
1998 struct U : public S, public T { };
2000 is not -- there's no way to decide whether to put `S::f' or
2001 `T::f' in the vtable for `R'.
2003 The solution is to look at all paths to BINFO. If we find
2004 different overriders along any two, then there is a problem. */
2005 if (DECL_THUNK_P (fn))
2006 fn = THUNK_TARGET (fn);
2008 /* Determine the depth of the hierarchy. */
2010 ffod.declaring_base = binfo;
2011 ffod.candidates = NULL_TREE;
2012 ffod.path = VEC_alloc (tree, heap, 30);
2014 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2015 dfs_find_final_overrider_post, &ffod);
2017 VEC_free (tree, heap, ffod.path);
2019 /* If there was no winner, issue an error message. */
2020 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2021 return error_mark_node;
2023 return ffod.candidates;
2026 /* Return the index of the vcall offset for FN when TYPE is used as a
2030 get_vcall_index (tree fn, tree type)
2032 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2036 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
2037 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2038 || same_signature_p (fn, p->purpose))
2041 /* There should always be an appropriate index. */
2045 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2046 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
2047 corresponding position in the BINFO_VIRTUALS list. */
2050 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2058 tree overrider_fn, overrider_target;
2059 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2060 tree over_return, base_return;
2063 /* Find the nearest primary base (possibly binfo itself) which defines
2064 this function; this is the class the caller will convert to when
2065 calling FN through BINFO. */
2066 for (b = binfo; ; b = get_primary_binfo (b))
2069 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2072 /* The nearest definition is from a lost primary. */
2073 if (BINFO_LOST_PRIMARY_P (b))
2078 /* Find the final overrider. */
2079 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2080 if (overrider == error_mark_node)
2082 error ("no unique final overrider for %qD in %qT", target_fn, t);
2085 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2087 /* Check for adjusting covariant return types. */
2088 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2089 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2091 if (POINTER_TYPE_P (over_return)
2092 && TREE_CODE (over_return) == TREE_CODE (base_return)
2093 && CLASS_TYPE_P (TREE_TYPE (over_return))
2094 && CLASS_TYPE_P (TREE_TYPE (base_return))
2095 /* If the overrider is invalid, don't even try. */
2096 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2098 /* If FN is a covariant thunk, we must figure out the adjustment
2099 to the final base FN was converting to. As OVERRIDER_TARGET might
2100 also be converting to the return type of FN, we have to
2101 combine the two conversions here. */
2102 tree fixed_offset, virtual_offset;
2104 over_return = TREE_TYPE (over_return);
2105 base_return = TREE_TYPE (base_return);
2107 if (DECL_THUNK_P (fn))
2109 gcc_assert (DECL_RESULT_THUNK_P (fn));
2110 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2111 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2114 fixed_offset = virtual_offset = NULL_TREE;
2117 /* Find the equivalent binfo within the return type of the
2118 overriding function. We will want the vbase offset from
2120 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2122 else if (!same_type_ignoring_top_level_qualifiers_p
2123 (over_return, base_return))
2125 /* There was no existing virtual thunk (which takes
2126 precedence). So find the binfo of the base function's
2127 return type within the overriding function's return type.
2128 We cannot call lookup base here, because we're inside a
2129 dfs_walk, and will therefore clobber the BINFO_MARKED
2130 flags. Fortunately we know the covariancy is valid (it
2131 has already been checked), so we can just iterate along
2132 the binfos, which have been chained in inheritance graph
2133 order. Of course it is lame that we have to repeat the
2134 search here anyway -- we should really be caching pieces
2135 of the vtable and avoiding this repeated work. */
2136 tree thunk_binfo, base_binfo;
2138 /* Find the base binfo within the overriding function's
2139 return type. We will always find a thunk_binfo, except
2140 when the covariancy is invalid (which we will have
2141 already diagnosed). */
2142 for (base_binfo = TYPE_BINFO (base_return),
2143 thunk_binfo = TYPE_BINFO (over_return);
2145 thunk_binfo = TREE_CHAIN (thunk_binfo))
2146 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2147 BINFO_TYPE (base_binfo)))
2150 /* See if virtual inheritance is involved. */
2151 for (virtual_offset = thunk_binfo;
2153 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2154 if (BINFO_VIRTUAL_P (virtual_offset))
2158 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2160 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2164 /* We convert via virtual base. Adjust the fixed
2165 offset to be from there. */
2167 size_diffop (offset,
2169 BINFO_OFFSET (virtual_offset)));
2172 /* There was an existing fixed offset, this must be
2173 from the base just converted to, and the base the
2174 FN was thunking to. */
2175 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2177 fixed_offset = offset;
2181 if (fixed_offset || virtual_offset)
2182 /* Replace the overriding function with a covariant thunk. We
2183 will emit the overriding function in its own slot as
2185 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2186 fixed_offset, virtual_offset);
2189 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2190 !DECL_THUNK_P (fn));
2192 /* Assume that we will produce a thunk that convert all the way to
2193 the final overrider, and not to an intermediate virtual base. */
2194 virtual_base = NULL_TREE;
2196 /* See if we can convert to an intermediate virtual base first, and then
2197 use the vcall offset located there to finish the conversion. */
2198 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2200 /* If we find the final overrider, then we can stop
2202 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2203 BINFO_TYPE (TREE_VALUE (overrider))))
2206 /* If we find a virtual base, and we haven't yet found the
2207 overrider, then there is a virtual base between the
2208 declaring base (first_defn) and the final overrider. */
2209 if (BINFO_VIRTUAL_P (b))
2216 if (overrider_fn != overrider_target && !virtual_base)
2218 /* The ABI specifies that a covariant thunk includes a mangling
2219 for a this pointer adjustment. This-adjusting thunks that
2220 override a function from a virtual base have a vcall
2221 adjustment. When the virtual base in question is a primary
2222 virtual base, we know the adjustments are zero, (and in the
2223 non-covariant case, we would not use the thunk).
2224 Unfortunately we didn't notice this could happen, when
2225 designing the ABI and so never mandated that such a covariant
2226 thunk should be emitted. Because we must use the ABI mandated
2227 name, we must continue searching from the binfo where we
2228 found the most recent definition of the function, towards the
2229 primary binfo which first introduced the function into the
2230 vtable. If that enters a virtual base, we must use a vcall
2231 this-adjusting thunk. Bleah! */
2232 tree probe = first_defn;
2234 while ((probe = get_primary_binfo (probe))
2235 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2236 if (BINFO_VIRTUAL_P (probe))
2237 virtual_base = probe;
2240 /* Even if we find a virtual base, the correct delta is
2241 between the overrider and the binfo we're building a vtable
2243 goto virtual_covariant;
2246 /* Compute the constant adjustment to the `this' pointer. The
2247 `this' pointer, when this function is called, will point at BINFO
2248 (or one of its primary bases, which are at the same offset). */
2250 /* The `this' pointer needs to be adjusted from the declaration to
2251 the nearest virtual base. */
2252 delta = size_diffop_loc (input_location,
2253 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2254 convert (ssizetype, BINFO_OFFSET (first_defn)));
2256 /* If the nearest definition is in a lost primary, we don't need an
2257 entry in our vtable. Except possibly in a constructor vtable,
2258 if we happen to get our primary back. In that case, the offset
2259 will be zero, as it will be a primary base. */
2260 delta = size_zero_node;
2262 /* The `this' pointer needs to be adjusted from pointing to
2263 BINFO to pointing at the base where the final overrider
2266 delta = size_diffop_loc (input_location,
2268 BINFO_OFFSET (TREE_VALUE (overrider))),
2269 convert (ssizetype, BINFO_OFFSET (binfo)));
2271 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2274 BV_VCALL_INDEX (*virtuals)
2275 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2277 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2280 /* Called from modify_all_vtables via dfs_walk. */
2283 dfs_modify_vtables (tree binfo, void* data)
2285 tree t = (tree) data;
2290 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2291 /* A base without a vtable needs no modification, and its bases
2292 are uninteresting. */
2293 return dfs_skip_bases;
2295 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2296 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2297 /* Don't do the primary vtable, if it's new. */
2300 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2301 /* There's no need to modify the vtable for a non-virtual primary
2302 base; we're not going to use that vtable anyhow. We do still
2303 need to do this for virtual primary bases, as they could become
2304 non-primary in a construction vtable. */
2307 make_new_vtable (t, binfo);
2309 /* Now, go through each of the virtual functions in the virtual
2310 function table for BINFO. Find the final overrider, and update
2311 the BINFO_VIRTUALS list appropriately. */
2312 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2313 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2315 ix++, virtuals = TREE_CHAIN (virtuals),
2316 old_virtuals = TREE_CHAIN (old_virtuals))
2317 update_vtable_entry_for_fn (t,
2319 BV_FN (old_virtuals),
2325 /* Update all of the primary and secondary vtables for T. Create new
2326 vtables as required, and initialize their RTTI information. Each
2327 of the functions in VIRTUALS is declared in T and may override a
2328 virtual function from a base class; find and modify the appropriate
2329 entries to point to the overriding functions. Returns a list, in
2330 declaration order, of the virtual functions that are declared in T,
2331 but do not appear in the primary base class vtable, and which
2332 should therefore be appended to the end of the vtable for T. */
2335 modify_all_vtables (tree t, tree virtuals)
2337 tree binfo = TYPE_BINFO (t);
2340 /* Update all of the vtables. */
2341 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2343 /* Add virtual functions not already in our primary vtable. These
2344 will be both those introduced by this class, and those overridden
2345 from secondary bases. It does not include virtuals merely
2346 inherited from secondary bases. */
2347 for (fnsp = &virtuals; *fnsp; )
2349 tree fn = TREE_VALUE (*fnsp);
2351 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2352 || DECL_VINDEX (fn) == error_mark_node)
2354 /* We don't need to adjust the `this' pointer when
2355 calling this function. */
2356 BV_DELTA (*fnsp) = integer_zero_node;
2357 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2359 /* This is a function not already in our vtable. Keep it. */
2360 fnsp = &TREE_CHAIN (*fnsp);
2363 /* We've already got an entry for this function. Skip it. */
2364 *fnsp = TREE_CHAIN (*fnsp);
2370 /* Get the base virtual function declarations in T that have the
2374 get_basefndecls (tree name, tree t)
2377 tree base_fndecls = NULL_TREE;
2378 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2381 /* Find virtual functions in T with the indicated NAME. */
2382 i = lookup_fnfields_1 (t, name);
2384 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2386 methods = OVL_NEXT (methods))
2388 tree method = OVL_CURRENT (methods);
2390 if (TREE_CODE (method) == FUNCTION_DECL
2391 && DECL_VINDEX (method))
2392 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2396 return base_fndecls;
2398 for (i = 0; i < n_baseclasses; i++)
2400 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2401 base_fndecls = chainon (get_basefndecls (name, basetype),
2405 return base_fndecls;
2408 /* If this declaration supersedes the declaration of
2409 a method declared virtual in the base class, then
2410 mark this field as being virtual as well. */
2413 check_for_override (tree decl, tree ctype)
2415 if (TREE_CODE (decl) == TEMPLATE_DECL)
2416 /* In [temp.mem] we have:
2418 A specialization of a member function template does not
2419 override a virtual function from a base class. */
2421 if ((DECL_DESTRUCTOR_P (decl)
2422 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2423 || DECL_CONV_FN_P (decl))
2424 && look_for_overrides (ctype, decl)
2425 && !DECL_STATIC_FUNCTION_P (decl))
2426 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2427 the error_mark_node so that we know it is an overriding
2429 DECL_VINDEX (decl) = decl;
2431 if (DECL_VIRTUAL_P (decl))
2433 if (!DECL_VINDEX (decl))
2434 DECL_VINDEX (decl) = error_mark_node;
2435 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2439 /* Warn about hidden virtual functions that are not overridden in t.
2440 We know that constructors and destructors don't apply. */
2443 warn_hidden (tree t)
2445 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2449 /* We go through each separately named virtual function. */
2450 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2451 VEC_iterate (tree, method_vec, i, fns);
2462 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2463 have the same name. Figure out what name that is. */
2464 name = DECL_NAME (OVL_CURRENT (fns));
2465 /* There are no possibly hidden functions yet. */
2466 base_fndecls = NULL_TREE;
2467 /* Iterate through all of the base classes looking for possibly
2468 hidden functions. */
2469 for (binfo = TYPE_BINFO (t), j = 0;
2470 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2472 tree basetype = BINFO_TYPE (base_binfo);
2473 base_fndecls = chainon (get_basefndecls (name, basetype),
2477 /* If there are no functions to hide, continue. */
2481 /* Remove any overridden functions. */
2482 for (fn = fns; fn; fn = OVL_NEXT (fn))
2484 fndecl = OVL_CURRENT (fn);
2485 if (DECL_VINDEX (fndecl))
2487 tree *prev = &base_fndecls;
2490 /* If the method from the base class has the same
2491 signature as the method from the derived class, it
2492 has been overridden. */
2493 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2494 *prev = TREE_CHAIN (*prev);
2496 prev = &TREE_CHAIN (*prev);
2500 /* Now give a warning for all base functions without overriders,
2501 as they are hidden. */
2502 while (base_fndecls)
2504 /* Here we know it is a hider, and no overrider exists. */
2505 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2506 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2507 base_fndecls = TREE_CHAIN (base_fndecls);
2512 /* Check for things that are invalid. There are probably plenty of other
2513 things we should check for also. */
2516 finish_struct_anon (tree t)
2520 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2522 if (TREE_STATIC (field))
2524 if (TREE_CODE (field) != FIELD_DECL)
2527 if (DECL_NAME (field) == NULL_TREE
2528 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2530 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2531 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2532 for (; elt; elt = TREE_CHAIN (elt))
2534 /* We're generally only interested in entities the user
2535 declared, but we also find nested classes by noticing
2536 the TYPE_DECL that we create implicitly. You're
2537 allowed to put one anonymous union inside another,
2538 though, so we explicitly tolerate that. We use
2539 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2540 we also allow unnamed types used for defining fields. */
2541 if (DECL_ARTIFICIAL (elt)
2542 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2543 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2546 if (TREE_CODE (elt) != FIELD_DECL)
2549 permerror (input_location, "%q+#D invalid; an anonymous union can "
2550 "only have non-static data members", elt);
2552 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2553 "only have non-static data members", elt);
2557 if (TREE_PRIVATE (elt))
2560 permerror (input_location, "private member %q+#D in anonymous union", elt);
2562 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2564 else if (TREE_PROTECTED (elt))
2567 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2569 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2572 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2573 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2579 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2580 will be used later during class template instantiation.
2581 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2582 a non-static member data (FIELD_DECL), a member function
2583 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2584 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2585 When FRIEND_P is nonzero, T is either a friend class
2586 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2587 (FUNCTION_DECL, TEMPLATE_DECL). */
2590 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2592 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2593 if (CLASSTYPE_TEMPLATE_INFO (type))
2594 CLASSTYPE_DECL_LIST (type)
2595 = tree_cons (friend_p ? NULL_TREE : type,
2596 t, CLASSTYPE_DECL_LIST (type));
2599 /* Create default constructors, assignment operators, and so forth for
2600 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2601 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2602 the class cannot have a default constructor, copy constructor
2603 taking a const reference argument, or an assignment operator taking
2604 a const reference, respectively. */
2607 add_implicitly_declared_members (tree t,
2608 int cant_have_const_cctor,
2609 int cant_have_const_assignment)
2612 if (!CLASSTYPE_DESTRUCTORS (t))
2614 /* In general, we create destructors lazily. */
2615 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2616 /* However, if the implicit destructor is non-trivial
2617 destructor, we sometimes have to create it at this point. */
2618 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2622 if (TYPE_FOR_JAVA (t))
2623 /* If this a Java class, any non-trivial destructor is
2624 invalid, even if compiler-generated. Therefore, if the
2625 destructor is non-trivial we create it now. */
2633 /* If the implicit destructor will be virtual, then we must
2634 generate it now because (unfortunately) we do not
2635 generate virtual tables lazily. */
2636 binfo = TYPE_BINFO (t);
2637 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2642 base_type = BINFO_TYPE (base_binfo);
2643 dtor = CLASSTYPE_DESTRUCTORS (base_type);
2644 if (dtor && DECL_VIRTUAL_P (dtor))
2652 /* If we can't get away with being lazy, generate the destructor
2655 lazily_declare_fn (sfk_destructor, t);
2661 If there is no user-declared constructor for a class, a default
2662 constructor is implicitly declared. */
2663 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2665 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2666 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2671 If a class definition does not explicitly declare a copy
2672 constructor, one is declared implicitly. */
2673 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2675 TYPE_HAS_INIT_REF (t) = 1;
2676 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2677 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2680 /* Currently only lambdas get a lazy move ctor, but N2987 adds them for
2682 if (LAMBDA_TYPE_P (t))
2683 CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
2685 /* If there is no assignment operator, one will be created if and
2686 when it is needed. For now, just record whether or not the type
2687 of the parameter to the assignment operator will be a const or
2688 non-const reference. */
2689 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2691 TYPE_HAS_ASSIGN_REF (t) = 1;
2692 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2693 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2697 /* Subroutine of finish_struct_1. Recursively count the number of fields
2698 in TYPE, including anonymous union members. */
2701 count_fields (tree fields)
2705 for (x = fields; x; x = TREE_CHAIN (x))
2707 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2708 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2715 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2716 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2719 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2722 for (x = fields; x; x = TREE_CHAIN (x))
2724 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2725 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2727 field_vec->elts[idx++] = x;
2732 /* FIELD is a bit-field. We are finishing the processing for its
2733 enclosing type. Issue any appropriate messages and set appropriate
2734 flags. Returns false if an error has been diagnosed. */
2737 check_bitfield_decl (tree field)
2739 tree type = TREE_TYPE (field);
2742 /* Extract the declared width of the bitfield, which has been
2743 temporarily stashed in DECL_INITIAL. */
2744 w = DECL_INITIAL (field);
2745 gcc_assert (w != NULL_TREE);
2746 /* Remove the bit-field width indicator so that the rest of the
2747 compiler does not treat that value as an initializer. */
2748 DECL_INITIAL (field) = NULL_TREE;
2750 /* Detect invalid bit-field type. */
2751 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2753 error ("bit-field %q+#D with non-integral type", field);
2754 w = error_mark_node;
2758 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2761 /* detect invalid field size. */
2762 w = integral_constant_value (w);
2764 if (TREE_CODE (w) != INTEGER_CST)
2766 error ("bit-field %q+D width not an integer constant", field);
2767 w = error_mark_node;
2769 else if (tree_int_cst_sgn (w) < 0)
2771 error ("negative width in bit-field %q+D", field);
2772 w = error_mark_node;
2774 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2776 error ("zero width for bit-field %q+D", field);
2777 w = error_mark_node;
2779 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2780 && TREE_CODE (type) != ENUMERAL_TYPE
2781 && TREE_CODE (type) != BOOLEAN_TYPE)
2782 warning (0, "width of %q+D exceeds its type", field);
2783 else if (TREE_CODE (type) == ENUMERAL_TYPE
2784 && (0 > compare_tree_int (w,
2785 tree_int_cst_min_precision
2786 (TYPE_MIN_VALUE (type),
2787 TYPE_UNSIGNED (type)))
2788 || 0 > compare_tree_int (w,
2789 tree_int_cst_min_precision
2790 (TYPE_MAX_VALUE (type),
2791 TYPE_UNSIGNED (type)))))
2792 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2795 if (w != error_mark_node)
2797 DECL_SIZE (field) = convert (bitsizetype, w);
2798 DECL_BIT_FIELD (field) = 1;
2803 /* Non-bit-fields are aligned for their type. */
2804 DECL_BIT_FIELD (field) = 0;
2805 CLEAR_DECL_C_BIT_FIELD (field);
2810 /* FIELD is a non bit-field. We are finishing the processing for its
2811 enclosing type T. Issue any appropriate messages and set appropriate
2815 check_field_decl (tree field,
2817 int* cant_have_const_ctor,
2818 int* no_const_asn_ref,
2819 int* any_default_members)
2821 tree type = strip_array_types (TREE_TYPE (field));
2823 /* An anonymous union cannot contain any fields which would change
2824 the settings of CANT_HAVE_CONST_CTOR and friends. */
2825 if (ANON_UNION_TYPE_P (type))
2827 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2828 structs. So, we recurse through their fields here. */
2829 else if (ANON_AGGR_TYPE_P (type))
2833 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2834 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2835 check_field_decl (fields, t, cant_have_const_ctor,
2836 no_const_asn_ref, any_default_members);
2838 /* Check members with class type for constructors, destructors,
2840 else if (CLASS_TYPE_P (type))
2842 /* Never let anything with uninheritable virtuals
2843 make it through without complaint. */
2844 abstract_virtuals_error (field, type);
2846 if (TREE_CODE (t) == UNION_TYPE)
2848 if (TYPE_NEEDS_CONSTRUCTING (type))
2849 error ("member %q+#D with constructor not allowed in union",
2851 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2852 error ("member %q+#D with destructor not allowed in union", field);
2853 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2854 error ("member %q+#D with copy assignment operator not allowed in union",
2859 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2860 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2861 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2862 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2863 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2864 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (type);
2867 if (!TYPE_HAS_CONST_INIT_REF (type))
2868 *cant_have_const_ctor = 1;
2870 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2871 *no_const_asn_ref = 1;
2873 if (DECL_INITIAL (field) != NULL_TREE)
2875 /* `build_class_init_list' does not recognize
2877 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2878 error ("multiple fields in union %qT initialized", t);
2879 *any_default_members = 1;
2883 /* Check the data members (both static and non-static), class-scoped
2884 typedefs, etc., appearing in the declaration of T. Issue
2885 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2886 declaration order) of access declarations; each TREE_VALUE in this
2887 list is a USING_DECL.
2889 In addition, set the following flags:
2892 The class is empty, i.e., contains no non-static data members.
2894 CANT_HAVE_CONST_CTOR_P
2895 This class cannot have an implicitly generated copy constructor
2896 taking a const reference.
2898 CANT_HAVE_CONST_ASN_REF
2899 This class cannot have an implicitly generated assignment
2900 operator taking a const reference.
2902 All of these flags should be initialized before calling this
2905 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2906 fields can be added by adding to this chain. */
2909 check_field_decls (tree t, tree *access_decls,
2910 int *cant_have_const_ctor_p,
2911 int *no_const_asn_ref_p)
2916 int any_default_members;
2918 int field_access = -1;
2920 /* Assume there are no access declarations. */
2921 *access_decls = NULL_TREE;
2922 /* Assume this class has no pointer members. */
2923 has_pointers = false;
2924 /* Assume none of the members of this class have default
2926 any_default_members = 0;
2928 for (field = &TYPE_FIELDS (t); *field; field = next)
2931 tree type = TREE_TYPE (x);
2932 int this_field_access;
2934 next = &TREE_CHAIN (x);
2936 if (TREE_CODE (x) == USING_DECL)
2938 /* Prune the access declaration from the list of fields. */
2939 *field = TREE_CHAIN (x);
2941 /* Save the access declarations for our caller. */
2942 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2944 /* Since we've reset *FIELD there's no reason to skip to the
2950 if (TREE_CODE (x) == TYPE_DECL
2951 || TREE_CODE (x) == TEMPLATE_DECL)
2954 /* If we've gotten this far, it's a data member, possibly static,
2955 or an enumerator. */
2956 DECL_CONTEXT (x) = t;
2958 /* When this goes into scope, it will be a non-local reference. */
2959 DECL_NONLOCAL (x) = 1;
2961 if (TREE_CODE (t) == UNION_TYPE)
2965 If a union contains a static data member, or a member of
2966 reference type, the program is ill-formed. */
2967 if (TREE_CODE (x) == VAR_DECL)
2969 error ("%q+D may not be static because it is a member of a union", x);
2972 if (TREE_CODE (type) == REFERENCE_TYPE)
2974 error ("%q+D may not have reference type %qT because"
2975 " it is a member of a union",
2981 /* Perform error checking that did not get done in
2983 if (TREE_CODE (type) == FUNCTION_TYPE)
2985 error ("field %q+D invalidly declared function type", x);
2986 type = build_pointer_type (type);
2987 TREE_TYPE (x) = type;
2989 else if (TREE_CODE (type) == METHOD_TYPE)
2991 error ("field %q+D invalidly declared method type", x);
2992 type = build_pointer_type (type);
2993 TREE_TYPE (x) = type;
2996 if (type == error_mark_node)
2999 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
3002 /* Now it can only be a FIELD_DECL. */
3004 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3005 CLASSTYPE_NON_AGGREGATE (t) = 1;
3007 /* A standard-layout class is a class that:
3009 has the same access control (Clause 11) for all non-static data members,
3011 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3012 if (field_access == -1)
3013 field_access = this_field_access;
3014 else if (this_field_access != field_access)
3015 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3017 /* If this is of reference type, check if it needs an init. */
3018 if (TREE_CODE (type) == REFERENCE_TYPE)
3020 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3021 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3022 if (DECL_INITIAL (x) == NULL_TREE)
3023 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3025 /* ARM $12.6.2: [A member initializer list] (or, for an
3026 aggregate, initialization by a brace-enclosed list) is the
3027 only way to initialize nonstatic const and reference
3029 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3032 type = strip_array_types (type);
3034 if (TYPE_PACKED (t))
3036 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3040 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3044 else if (DECL_C_BIT_FIELD (x)
3045 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3046 DECL_PACKED (x) = 1;
3049 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3050 /* We don't treat zero-width bitfields as making a class
3055 /* The class is non-empty. */
3056 CLASSTYPE_EMPTY_P (t) = 0;
3057 /* The class is not even nearly empty. */
3058 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3059 /* If one of the data members contains an empty class,
3061 if (CLASS_TYPE_P (type)
3062 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3063 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3066 /* This is used by -Weffc++ (see below). Warn only for pointers
3067 to members which might hold dynamic memory. So do not warn
3068 for pointers to functions or pointers to members. */
3069 if (TYPE_PTR_P (type)
3070 && !TYPE_PTRFN_P (type)
3071 && !TYPE_PTR_TO_MEMBER_P (type))
3072 has_pointers = true;
3074 if (CLASS_TYPE_P (type))
3076 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3077 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3078 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3079 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3082 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3083 CLASSTYPE_HAS_MUTABLE (t) = 1;
3085 if (! layout_pod_type_p (type))
3086 /* DR 148 now allows pointers to members (which are POD themselves),
3087 to be allowed in POD structs. */
3088 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3090 if (!std_layout_type_p (type))
3091 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3093 if (! zero_init_p (type))
3094 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3096 /* If any field is const, the structure type is pseudo-const. */
3097 if (CP_TYPE_CONST_P (type))
3099 C_TYPE_FIELDS_READONLY (t) = 1;
3100 if (DECL_INITIAL (x) == NULL_TREE)
3101 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3103 /* ARM $12.6.2: [A member initializer list] (or, for an
3104 aggregate, initialization by a brace-enclosed list) is the
3105 only way to initialize nonstatic const and reference
3107 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3109 /* A field that is pseudo-const makes the structure likewise. */
3110 else if (CLASS_TYPE_P (type))
3112 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3113 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3114 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3115 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3118 /* Core issue 80: A nonstatic data member is required to have a
3119 different name from the class iff the class has a
3120 user-declared constructor. */
3121 if (constructor_name_p (DECL_NAME (x), t)
3122 && TYPE_HAS_USER_CONSTRUCTOR (t))
3123 permerror (input_location, "field %q+#D with same name as class", x);
3125 /* We set DECL_C_BIT_FIELD in grokbitfield.
3126 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3127 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3128 check_field_decl (x, t,
3129 cant_have_const_ctor_p,
3131 &any_default_members);
3134 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3135 it should also define a copy constructor and an assignment operator to
3136 implement the correct copy semantic (deep vs shallow, etc.). As it is
3137 not feasible to check whether the constructors do allocate dynamic memory
3138 and store it within members, we approximate the warning like this:
3140 -- Warn only if there are members which are pointers
3141 -- Warn only if there is a non-trivial constructor (otherwise,
3142 there cannot be memory allocated).
3143 -- Warn only if there is a non-trivial destructor. We assume that the
3144 user at least implemented the cleanup correctly, and a destructor
3145 is needed to free dynamic memory.
3147 This seems enough for practical purposes. */
3150 && TYPE_HAS_USER_CONSTRUCTOR (t)
3151 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3152 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3154 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3156 if (! TYPE_HAS_INIT_REF (t))
3158 warning (OPT_Weffc__,
3159 " but does not override %<%T(const %T&)%>", t, t);
3160 if (!TYPE_HAS_ASSIGN_REF (t))
3161 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3163 else if (! TYPE_HAS_ASSIGN_REF (t))
3164 warning (OPT_Weffc__,
3165 " but does not override %<operator=(const %T&)%>", t);
3168 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3170 TYPE_PACKED (t) = 0;
3172 /* Check anonymous struct/anonymous union fields. */
3173 finish_struct_anon (t);
3175 /* We've built up the list of access declarations in reverse order.
3177 *access_decls = nreverse (*access_decls);
3180 /* If TYPE is an empty class type, records its OFFSET in the table of
3184 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3188 if (!is_empty_class (type))
3191 /* Record the location of this empty object in OFFSETS. */
3192 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3194 n = splay_tree_insert (offsets,
3195 (splay_tree_key) offset,
3196 (splay_tree_value) NULL_TREE);
3197 n->value = ((splay_tree_value)
3198 tree_cons (NULL_TREE,
3205 /* Returns nonzero if TYPE is an empty class type and there is
3206 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3209 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3214 if (!is_empty_class (type))
3217 /* Record the location of this empty object in OFFSETS. */
3218 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3222 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3223 if (same_type_p (TREE_VALUE (t), type))
3229 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3230 F for every subobject, passing it the type, offset, and table of
3231 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3234 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3235 than MAX_OFFSET will not be walked.
3237 If F returns a nonzero value, the traversal ceases, and that value
3238 is returned. Otherwise, returns zero. */
3241 walk_subobject_offsets (tree type,
3242 subobject_offset_fn f,
3249 tree type_binfo = NULL_TREE;
3251 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3253 if (max_offset && INT_CST_LT (max_offset, offset))
3256 if (type == error_mark_node)
3261 if (abi_version_at_least (2))
3263 type = BINFO_TYPE (type);
3266 if (CLASS_TYPE_P (type))
3272 /* Avoid recursing into objects that are not interesting. */
3273 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3276 /* Record the location of TYPE. */
3277 r = (*f) (type, offset, offsets);
3281 /* Iterate through the direct base classes of TYPE. */
3283 type_binfo = TYPE_BINFO (type);
3284 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3288 if (abi_version_at_least (2)
3289 && BINFO_VIRTUAL_P (binfo))
3293 && BINFO_VIRTUAL_P (binfo)
3294 && !BINFO_PRIMARY_P (binfo))
3297 if (!abi_version_at_least (2))
3298 binfo_offset = size_binop (PLUS_EXPR,
3300 BINFO_OFFSET (binfo));
3304 /* We cannot rely on BINFO_OFFSET being set for the base
3305 class yet, but the offsets for direct non-virtual
3306 bases can be calculated by going back to the TYPE. */
3307 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3308 binfo_offset = size_binop (PLUS_EXPR,
3310 BINFO_OFFSET (orig_binfo));
3313 r = walk_subobject_offsets (binfo,
3318 (abi_version_at_least (2)
3319 ? /*vbases_p=*/0 : vbases_p));
3324 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3327 VEC(tree,gc) *vbases;
3329 /* Iterate through the virtual base classes of TYPE. In G++
3330 3.2, we included virtual bases in the direct base class
3331 loop above, which results in incorrect results; the
3332 correct offsets for virtual bases are only known when
3333 working with the most derived type. */
3335 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3336 VEC_iterate (tree, vbases, ix, binfo); ix++)
3338 r = walk_subobject_offsets (binfo,
3340 size_binop (PLUS_EXPR,
3342 BINFO_OFFSET (binfo)),
3351 /* We still have to walk the primary base, if it is
3352 virtual. (If it is non-virtual, then it was walked
3354 tree vbase = get_primary_binfo (type_binfo);
3356 if (vbase && BINFO_VIRTUAL_P (vbase)
3357 && BINFO_PRIMARY_P (vbase)
3358 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3360 r = (walk_subobject_offsets
3362 offsets, max_offset, /*vbases_p=*/0));
3369 /* Iterate through the fields of TYPE. */
3370 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3371 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3375 if (abi_version_at_least (2))
3376 field_offset = byte_position (field);
3378 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3379 field_offset = DECL_FIELD_OFFSET (field);
3381 r = walk_subobject_offsets (TREE_TYPE (field),
3383 size_binop (PLUS_EXPR,
3393 else if (TREE_CODE (type) == ARRAY_TYPE)
3395 tree element_type = strip_array_types (type);
3396 tree domain = TYPE_DOMAIN (type);
3399 /* Avoid recursing into objects that are not interesting. */
3400 if (!CLASS_TYPE_P (element_type)
3401 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3404 /* Step through each of the elements in the array. */
3405 for (index = size_zero_node;
3406 /* G++ 3.2 had an off-by-one error here. */
3407 (abi_version_at_least (2)
3408 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3409 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3410 index = size_binop (PLUS_EXPR, index, size_one_node))
3412 r = walk_subobject_offsets (TREE_TYPE (type),
3420 offset = size_binop (PLUS_EXPR, offset,
3421 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3422 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3423 there's no point in iterating through the remaining
3424 elements of the array. */
3425 if (max_offset && INT_CST_LT (max_offset, offset))
3433 /* Record all of the empty subobjects of TYPE (either a type or a
3434 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3435 is being placed at OFFSET; otherwise, it is a base class that is
3436 being placed at OFFSET. */
3439 record_subobject_offsets (tree type,
3442 bool is_data_member)
3445 /* If recording subobjects for a non-static data member or a
3446 non-empty base class , we do not need to record offsets beyond
3447 the size of the biggest empty class. Additional data members
3448 will go at the end of the class. Additional base classes will go
3449 either at offset zero (if empty, in which case they cannot
3450 overlap with offsets past the size of the biggest empty class) or
3451 at the end of the class.
3453 However, if we are placing an empty base class, then we must record
3454 all offsets, as either the empty class is at offset zero (where
3455 other empty classes might later be placed) or at the end of the
3456 class (where other objects might then be placed, so other empty
3457 subobjects might later overlap). */
3459 || !is_empty_class (BINFO_TYPE (type)))
3460 max_offset = sizeof_biggest_empty_class;
3462 max_offset = NULL_TREE;
3463 walk_subobject_offsets (type, record_subobject_offset, offset,
3464 offsets, max_offset, is_data_member);
3467 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3468 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3469 virtual bases of TYPE are examined. */
3472 layout_conflict_p (tree type,
3477 splay_tree_node max_node;
3479 /* Get the node in OFFSETS that indicates the maximum offset where
3480 an empty subobject is located. */
3481 max_node = splay_tree_max (offsets);
3482 /* If there aren't any empty subobjects, then there's no point in
3483 performing this check. */
3487 return walk_subobject_offsets (type, check_subobject_offset, offset,
3488 offsets, (tree) (max_node->key),
3492 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3493 non-static data member of the type indicated by RLI. BINFO is the
3494 binfo corresponding to the base subobject, OFFSETS maps offsets to
3495 types already located at those offsets. This function determines
3496 the position of the DECL. */
3499 layout_nonempty_base_or_field (record_layout_info rli,
3504 tree offset = NULL_TREE;
3510 /* For the purposes of determining layout conflicts, we want to
3511 use the class type of BINFO; TREE_TYPE (DECL) will be the
3512 CLASSTYPE_AS_BASE version, which does not contain entries for
3513 zero-sized bases. */
3514 type = TREE_TYPE (binfo);
3519 type = TREE_TYPE (decl);
3523 /* Try to place the field. It may take more than one try if we have
3524 a hard time placing the field without putting two objects of the
3525 same type at the same address. */
3528 struct record_layout_info_s old_rli = *rli;
3530 /* Place this field. */
3531 place_field (rli, decl);
3532 offset = byte_position (decl);
3534 /* We have to check to see whether or not there is already
3535 something of the same type at the offset we're about to use.
3536 For example, consider:
3539 struct T : public S { int i; };
3540 struct U : public S, public T {};
3542 Here, we put S at offset zero in U. Then, we can't put T at
3543 offset zero -- its S component would be at the same address
3544 as the S we already allocated. So, we have to skip ahead.
3545 Since all data members, including those whose type is an
3546 empty class, have nonzero size, any overlap can happen only
3547 with a direct or indirect base-class -- it can't happen with
3549 /* In a union, overlap is permitted; all members are placed at
3551 if (TREE_CODE (rli->t) == UNION_TYPE)
3553 /* G++ 3.2 did not check for overlaps when placing a non-empty
3555 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3557 if (layout_conflict_p (field_p ? type : binfo, offset,
3560 /* Strip off the size allocated to this field. That puts us
3561 at the first place we could have put the field with
3562 proper alignment. */
3565 /* Bump up by the alignment required for the type. */
3567 = size_binop (PLUS_EXPR, rli->bitpos,
3569 ? CLASSTYPE_ALIGN (type)
3570 : TYPE_ALIGN (type)));
3571 normalize_rli (rli);
3574 /* There was no conflict. We're done laying out this field. */
3578 /* Now that we know where it will be placed, update its
3580 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3581 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3582 this point because their BINFO_OFFSET is copied from another
3583 hierarchy. Therefore, we may not need to add the entire
3585 propagate_binfo_offsets (binfo,
3586 size_diffop_loc (input_location,
3587 convert (ssizetype, offset),
3589 BINFO_OFFSET (binfo))));
3592 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3595 empty_base_at_nonzero_offset_p (tree type,
3597 splay_tree offsets ATTRIBUTE_UNUSED)
3599 return is_empty_class (type) && !integer_zerop (offset);
3602 /* Layout the empty base BINFO. EOC indicates the byte currently just
3603 past the end of the class, and should be correctly aligned for a
3604 class of the type indicated by BINFO; OFFSETS gives the offsets of
3605 the empty bases allocated so far. T is the most derived
3606 type. Return nonzero iff we added it at the end. */
3609 layout_empty_base (record_layout_info rli, tree binfo,
3610 tree eoc, splay_tree offsets)
3613 tree basetype = BINFO_TYPE (binfo);
3616 /* This routine should only be used for empty classes. */
3617 gcc_assert (is_empty_class (basetype));
3618 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3620 if (!integer_zerop (BINFO_OFFSET (binfo)))
3622 if (abi_version_at_least (2))
3623 propagate_binfo_offsets
3624 (binfo, size_diffop_loc (input_location,
3625 size_zero_node, BINFO_OFFSET (binfo)));
3628 "offset of empty base %qT may not be ABI-compliant and may"
3629 "change in a future version of GCC",
3630 BINFO_TYPE (binfo));
3633 /* This is an empty base class. We first try to put it at offset
3635 if (layout_conflict_p (binfo,
3636 BINFO_OFFSET (binfo),
3640 /* That didn't work. Now, we move forward from the next
3641 available spot in the class. */
3643 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3646 if (!layout_conflict_p (binfo,
3647 BINFO_OFFSET (binfo),
3650 /* We finally found a spot where there's no overlap. */
3653 /* There's overlap here, too. Bump along to the next spot. */
3654 propagate_binfo_offsets (binfo, alignment);
3658 if (CLASSTYPE_USER_ALIGN (basetype))
3660 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3662 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3663 TYPE_USER_ALIGN (rli->t) = 1;
3669 /* Layout the base given by BINFO in the class indicated by RLI.
3670 *BASE_ALIGN is a running maximum of the alignments of
3671 any base class. OFFSETS gives the location of empty base
3672 subobjects. T is the most derived type. Return nonzero if the new
3673 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3674 *NEXT_FIELD, unless BINFO is for an empty base class.
3676 Returns the location at which the next field should be inserted. */
3679 build_base_field (record_layout_info rli, tree binfo,
3680 splay_tree offsets, tree *next_field)
3683 tree basetype = BINFO_TYPE (binfo);
3685 if (!COMPLETE_TYPE_P (basetype))
3686 /* This error is now reported in xref_tag, thus giving better
3687 location information. */
3690 /* Place the base class. */
3691 if (!is_empty_class (basetype))
3695 /* The containing class is non-empty because it has a non-empty
3697 CLASSTYPE_EMPTY_P (t) = 0;
3699 /* Create the FIELD_DECL. */
3700 decl = build_decl (input_location,
3701 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3702 DECL_ARTIFICIAL (decl) = 1;
3703 DECL_IGNORED_P (decl) = 1;
3704 DECL_FIELD_CONTEXT (decl) = t;
3705 if (CLASSTYPE_AS_BASE (basetype))
3707 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3708 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3709 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3710 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3711 DECL_MODE (decl) = TYPE_MODE (basetype);
3712 DECL_FIELD_IS_BASE (decl) = 1;
3714 /* Try to place the field. It may take more than one try if we
3715 have a hard time placing the field without putting two
3716 objects of the same type at the same address. */
3717 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3718 /* Add the new FIELD_DECL to the list of fields for T. */
3719 TREE_CHAIN (decl) = *next_field;
3721 next_field = &TREE_CHAIN (decl);
3729 /* On some platforms (ARM), even empty classes will not be
3731 eoc = round_up_loc (input_location,
3732 rli_size_unit_so_far (rli),
3733 CLASSTYPE_ALIGN_UNIT (basetype));
3734 atend = layout_empty_base (rli, binfo, eoc, offsets);
3735 /* A nearly-empty class "has no proper base class that is empty,
3736 not morally virtual, and at an offset other than zero." */
3737 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3740 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3741 /* The check above (used in G++ 3.2) is insufficient because
3742 an empty class placed at offset zero might itself have an
3743 empty base at a nonzero offset. */
3744 else if (walk_subobject_offsets (basetype,
3745 empty_base_at_nonzero_offset_p,
3748 /*max_offset=*/NULL_TREE,
3751 if (abi_version_at_least (2))
3752 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3755 "class %qT will be considered nearly empty in a "
3756 "future version of GCC", t);
3760 /* We do not create a FIELD_DECL for empty base classes because
3761 it might overlap some other field. We want to be able to
3762 create CONSTRUCTORs for the class by iterating over the
3763 FIELD_DECLs, and the back end does not handle overlapping
3766 /* An empty virtual base causes a class to be non-empty
3767 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3768 here because that was already done when the virtual table
3769 pointer was created. */
3772 /* Record the offsets of BINFO and its base subobjects. */
3773 record_subobject_offsets (binfo,
3774 BINFO_OFFSET (binfo),
3776 /*is_data_member=*/false);
3781 /* Layout all of the non-virtual base classes. Record empty
3782 subobjects in OFFSETS. T is the most derived type. Return nonzero
3783 if the type cannot be nearly empty. The fields created
3784 corresponding to the base classes will be inserted at
3788 build_base_fields (record_layout_info rli,
3789 splay_tree offsets, tree *next_field)
3791 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3794 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3797 /* The primary base class is always allocated first. */
3798 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3799 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3800 offsets, next_field);
3802 /* Now allocate the rest of the bases. */
3803 for (i = 0; i < n_baseclasses; ++i)
3807 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3809 /* The primary base was already allocated above, so we don't
3810 need to allocate it again here. */
3811 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3814 /* Virtual bases are added at the end (a primary virtual base
3815 will have already been added). */
3816 if (BINFO_VIRTUAL_P (base_binfo))
3819 next_field = build_base_field (rli, base_binfo,
3820 offsets, next_field);
3824 /* Go through the TYPE_METHODS of T issuing any appropriate
3825 diagnostics, figuring out which methods override which other
3826 methods, and so forth. */
3829 check_methods (tree t)
3833 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3835 check_for_override (x, t);
3836 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3837 error ("initializer specified for non-virtual method %q+D", x);
3838 /* The name of the field is the original field name
3839 Save this in auxiliary field for later overloading. */
3840 if (DECL_VINDEX (x))
3842 TYPE_POLYMORPHIC_P (t) = 1;
3843 if (DECL_PURE_VIRTUAL_P (x))
3844 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3846 /* All user-provided destructors are non-trivial. */
3847 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
3848 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3852 /* FN is a constructor or destructor. Clone the declaration to create
3853 a specialized in-charge or not-in-charge version, as indicated by
3857 build_clone (tree fn, tree name)
3862 /* Copy the function. */
3863 clone = copy_decl (fn);
3864 /* Reset the function name. */
3865 DECL_NAME (clone) = name;
3866 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3867 /* Remember where this function came from. */
3868 DECL_ABSTRACT_ORIGIN (clone) = fn;
3869 /* Make it easy to find the CLONE given the FN. */
3870 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3871 TREE_CHAIN (fn) = clone;
3873 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3874 if (TREE_CODE (clone) == TEMPLATE_DECL)
3876 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3877 DECL_TEMPLATE_RESULT (clone) = result;
3878 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3879 DECL_TI_TEMPLATE (result) = clone;
3880 TREE_TYPE (clone) = TREE_TYPE (result);
3884 DECL_CLONED_FUNCTION (clone) = fn;
3885 /* There's no pending inline data for this function. */
3886 DECL_PENDING_INLINE_INFO (clone) = NULL;
3887 DECL_PENDING_INLINE_P (clone) = 0;
3889 /* The base-class destructor is not virtual. */
3890 if (name == base_dtor_identifier)
3892 DECL_VIRTUAL_P (clone) = 0;
3893 if (TREE_CODE (clone) != TEMPLATE_DECL)
3894 DECL_VINDEX (clone) = NULL_TREE;
3897 /* If there was an in-charge parameter, drop it from the function
3899 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3905 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3906 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3907 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3908 /* Skip the `this' parameter. */
3909 parmtypes = TREE_CHAIN (parmtypes);
3910 /* Skip the in-charge parameter. */
3911 parmtypes = TREE_CHAIN (parmtypes);
3912 /* And the VTT parm, in a complete [cd]tor. */
3913 if (DECL_HAS_VTT_PARM_P (fn)
3914 && ! DECL_NEEDS_VTT_PARM_P (clone))
3915 parmtypes = TREE_CHAIN (parmtypes);
3916 /* If this is subobject constructor or destructor, add the vtt
3919 = build_method_type_directly (basetype,
3920 TREE_TYPE (TREE_TYPE (clone)),
3923 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3926 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3927 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3930 /* Copy the function parameters. */
3931 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3932 /* Remove the in-charge parameter. */
3933 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3935 TREE_CHAIN (DECL_ARGUMENTS (clone))
3936 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3937 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3939 /* And the VTT parm, in a complete [cd]tor. */
3940 if (DECL_HAS_VTT_PARM_P (fn))
3942 if (DECL_NEEDS_VTT_PARM_P (clone))
3943 DECL_HAS_VTT_PARM_P (clone) = 1;
3946 TREE_CHAIN (DECL_ARGUMENTS (clone))
3947 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3948 DECL_HAS_VTT_PARM_P (clone) = 0;
3952 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3954 DECL_CONTEXT (parms) = clone;
3955 cxx_dup_lang_specific_decl (parms);
3958 /* Create the RTL for this function. */
3959 SET_DECL_RTL (clone, NULL_RTX);
3960 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3963 note_decl_for_pch (clone);
3968 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
3969 not invoke this function directly.
3971 For a non-thunk function, returns the address of the slot for storing
3972 the function it is a clone of. Otherwise returns NULL_TREE.
3974 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
3975 cloned_function is unset. This is to support the separate
3976 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
3977 on a template makes sense, but not the former. */
3980 decl_cloned_function_p (const_tree decl, bool just_testing)
3984 decl = STRIP_TEMPLATE (decl);
3986 if (TREE_CODE (decl) != FUNCTION_DECL
3987 || !DECL_LANG_SPECIFIC (decl)
3988 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
3990 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
3992 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
3998 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
3999 if (just_testing && *ptr == NULL_TREE)
4005 /* Produce declarations for all appropriate clones of FN. If
4006 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4007 CLASTYPE_METHOD_VEC as well. */
4010 clone_function_decl (tree fn, int update_method_vec_p)
4014 /* Avoid inappropriate cloning. */
4016 && DECL_CLONED_FUNCTION_P (TREE_CHAIN (fn)))
4019 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4021 /* For each constructor, we need two variants: an in-charge version
4022 and a not-in-charge version. */
4023 clone = build_clone (fn, complete_ctor_identifier);
4024 if (update_method_vec_p)
4025 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4026 clone = build_clone (fn, base_ctor_identifier);
4027 if (update_method_vec_p)
4028 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4032 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4034 /* For each destructor, we need three variants: an in-charge
4035 version, a not-in-charge version, and an in-charge deleting
4036 version. We clone the deleting version first because that
4037 means it will go second on the TYPE_METHODS list -- and that
4038 corresponds to the correct layout order in the virtual
4041 For a non-virtual destructor, we do not build a deleting
4043 if (DECL_VIRTUAL_P (fn))
4045 clone = build_clone (fn, deleting_dtor_identifier);
4046 if (update_method_vec_p)
4047 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4049 clone = build_clone (fn, complete_dtor_identifier);
4050 if (update_method_vec_p)
4051 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4052 clone = build_clone (fn, base_dtor_identifier);
4053 if (update_method_vec_p)
4054 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4057 /* Note that this is an abstract function that is never emitted. */
4058 DECL_ABSTRACT (fn) = 1;
4061 /* DECL is an in charge constructor, which is being defined. This will
4062 have had an in class declaration, from whence clones were
4063 declared. An out-of-class definition can specify additional default
4064 arguments. As it is the clones that are involved in overload
4065 resolution, we must propagate the information from the DECL to its
4069 adjust_clone_args (tree decl)
4073 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4074 clone = TREE_CHAIN (clone))
4076 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4077 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4078 tree decl_parms, clone_parms;
4080 clone_parms = orig_clone_parms;
4082 /* Skip the 'this' parameter. */
4083 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4084 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4086 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4087 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4088 if (DECL_HAS_VTT_PARM_P (decl))
4089 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4091 clone_parms = orig_clone_parms;
4092 if (DECL_HAS_VTT_PARM_P (clone))
4093 clone_parms = TREE_CHAIN (clone_parms);
4095 for (decl_parms = orig_decl_parms; decl_parms;
4096 decl_parms = TREE_CHAIN (decl_parms),
4097 clone_parms = TREE_CHAIN (clone_parms))
4099 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4100 TREE_TYPE (clone_parms)));
4102 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4104 /* A default parameter has been added. Adjust the
4105 clone's parameters. */
4106 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4107 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4108 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4111 clone_parms = orig_decl_parms;
4113 if (DECL_HAS_VTT_PARM_P (clone))
4115 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4116 TREE_VALUE (orig_clone_parms),
4118 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4120 type = build_method_type_directly (basetype,
4121 TREE_TYPE (TREE_TYPE (clone)),
4124 type = build_exception_variant (type, exceptions);
4126 type = cp_build_type_attribute_variant (type, attrs);
4127 TREE_TYPE (clone) = type;
4129 clone_parms = NULL_TREE;
4133 gcc_assert (!clone_parms);
4137 /* For each of the constructors and destructors in T, create an
4138 in-charge and not-in-charge variant. */
4141 clone_constructors_and_destructors (tree t)
4145 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4147 if (!CLASSTYPE_METHOD_VEC (t))
4150 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4151 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4152 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4153 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4156 /* Returns true iff class T has a user-defined constructor other than
4157 the default constructor. */
4160 type_has_user_nondefault_constructor (tree t)
4164 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4167 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4169 tree fn = OVL_CURRENT (fns);
4170 if (!DECL_ARTIFICIAL (fn)
4171 && (TREE_CODE (fn) == TEMPLATE_DECL
4172 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4180 /* Returns true iff FN is a user-provided function, i.e. user-declared
4181 and not defaulted at its first declaration; or explicit, private,
4182 protected, or non-const. */
4185 user_provided_p (tree fn)
4187 if (TREE_CODE (fn) == TEMPLATE_DECL)
4190 return (!DECL_ARTIFICIAL (fn)
4191 && !DECL_DEFAULTED_IN_CLASS_P (fn));
4194 /* Returns true iff class T has a user-provided constructor. */
4197 type_has_user_provided_constructor (tree t)
4201 if (!CLASS_TYPE_P (t))
4204 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4207 /* This can happen in error cases; avoid crashing. */
4208 if (!CLASSTYPE_METHOD_VEC (t))
4211 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4212 if (user_provided_p (OVL_CURRENT (fns)))
4218 /* Returns true iff class T has a user-provided default constructor. */
4221 type_has_user_provided_default_constructor (tree t)
4225 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4228 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4230 tree fn = OVL_CURRENT (fns);
4231 if (TREE_CODE (fn) == FUNCTION_DECL
4232 && user_provided_p (fn))
4234 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4235 while (args && TREE_PURPOSE (args))
4236 args = TREE_CHAIN (args);
4237 if (!args || args == void_list_node)
4245 /* Remove all zero-width bit-fields from T. */
4248 remove_zero_width_bit_fields (tree t)
4252 fieldsp = &TYPE_FIELDS (t);
4255 if (TREE_CODE (*fieldsp) == FIELD_DECL
4256 && DECL_C_BIT_FIELD (*fieldsp)
4257 && DECL_INITIAL (*fieldsp))
4258 *fieldsp = TREE_CHAIN (*fieldsp);
4260 fieldsp = &TREE_CHAIN (*fieldsp);
4264 /* Returns TRUE iff we need a cookie when dynamically allocating an
4265 array whose elements have the indicated class TYPE. */
4268 type_requires_array_cookie (tree type)
4271 bool has_two_argument_delete_p = false;
4273 gcc_assert (CLASS_TYPE_P (type));
4275 /* If there's a non-trivial destructor, we need a cookie. In order
4276 to iterate through the array calling the destructor for each
4277 element, we'll have to know how many elements there are. */
4278 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4281 /* If the usual deallocation function is a two-argument whose second
4282 argument is of type `size_t', then we have to pass the size of
4283 the array to the deallocation function, so we will need to store
4285 fns = lookup_fnfields (TYPE_BINFO (type),
4286 ansi_opname (VEC_DELETE_EXPR),
4288 /* If there are no `operator []' members, or the lookup is
4289 ambiguous, then we don't need a cookie. */
4290 if (!fns || fns == error_mark_node)
4292 /* Loop through all of the functions. */
4293 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4298 /* Select the current function. */
4299 fn = OVL_CURRENT (fns);
4300 /* See if this function is a one-argument delete function. If
4301 it is, then it will be the usual deallocation function. */
4302 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4303 if (second_parm == void_list_node)
4305 /* Do not consider this function if its second argument is an
4309 /* Otherwise, if we have a two-argument function and the second
4310 argument is `size_t', it will be the usual deallocation
4311 function -- unless there is one-argument function, too. */
4312 if (TREE_CHAIN (second_parm) == void_list_node
4313 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4314 has_two_argument_delete_p = true;
4317 return has_two_argument_delete_p;
4320 /* Check the validity of the bases and members declared in T. Add any
4321 implicitly-generated functions (like copy-constructors and
4322 assignment operators). Compute various flag bits (like
4323 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4324 level: i.e., independently of the ABI in use. */
4327 check_bases_and_members (tree t)
4329 /* Nonzero if the implicitly generated copy constructor should take
4330 a non-const reference argument. */
4331 int cant_have_const_ctor;
4332 /* Nonzero if the implicitly generated assignment operator
4333 should take a non-const reference argument. */
4334 int no_const_asn_ref;
4336 bool saved_complex_asn_ref;
4337 bool saved_nontrivial_dtor;
4340 /* By default, we use const reference arguments and generate default
4342 cant_have_const_ctor = 0;
4343 no_const_asn_ref = 0;
4345 /* Check all the base-classes. */
4346 check_bases (t, &cant_have_const_ctor,
4349 /* Check all the method declarations. */
4352 /* Save the initial values of these flags which only indicate whether
4353 or not the class has user-provided functions. As we analyze the
4354 bases and members we can set these flags for other reasons. */
4355 saved_complex_asn_ref = TYPE_HAS_COMPLEX_ASSIGN_REF (t);
4356 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4358 /* Check all the data member declarations. We cannot call
4359 check_field_decls until we have called check_bases check_methods,
4360 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4361 being set appropriately. */
4362 check_field_decls (t, &access_decls,
4363 &cant_have_const_ctor,
4366 /* A nearly-empty class has to be vptr-containing; a nearly empty
4367 class contains just a vptr. */
4368 if (!TYPE_CONTAINS_VPTR_P (t))
4369 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4371 /* Do some bookkeeping that will guide the generation of implicitly
4372 declared member functions. */
4373 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4374 /* We need to call a constructor for this class if it has a
4375 user-provided constructor, or if the default constructor is going
4376 to initialize the vptr. (This is not an if-and-only-if;
4377 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4378 themselves need constructing.) */
4379 TYPE_NEEDS_CONSTRUCTING (t)
4380 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4383 An aggregate is an array or a class with no user-provided
4384 constructors ... and no virtual functions.
4386 Again, other conditions for being an aggregate are checked
4388 CLASSTYPE_NON_AGGREGATE (t)
4389 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4390 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4391 retain the old definition internally for ABI reasons. */
4392 CLASSTYPE_NON_LAYOUT_POD_P (t)
4393 |= (CLASSTYPE_NON_AGGREGATE (t)
4394 || saved_nontrivial_dtor || saved_complex_asn_ref);
4395 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
4396 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4397 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4399 /* If the class has no user-declared constructor, but does have
4400 non-static const or reference data members that can never be
4401 initialized, issue a warning. */
4402 if (warn_uninitialized
4403 /* Classes with user-declared constructors are presumed to
4404 initialize these members. */
4405 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4406 /* Aggregates can be initialized with brace-enclosed
4408 && CLASSTYPE_NON_AGGREGATE (t))
4412 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4416 if (TREE_CODE (field) != FIELD_DECL)
4419 type = TREE_TYPE (field);
4420 if (TREE_CODE (type) == REFERENCE_TYPE)
4421 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4422 "in class without a constructor", field);
4423 else if (CP_TYPE_CONST_P (type)
4424 && (!CLASS_TYPE_P (type)
4425 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4426 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4427 "in class without a constructor", field);
4431 /* Synthesize any needed methods. */
4432 add_implicitly_declared_members (t,
4433 cant_have_const_ctor,
4436 /* Check defaulted declarations here so we have cant_have_const_ctor
4437 and don't need to worry about clones. */
4438 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4439 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4441 int copy = copy_fn_p (fn);
4445 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
4446 : !no_const_asn_ref);
4447 bool fn_const_p = (copy == 2);
4449 if (fn_const_p && !imp_const_p)
4450 /* If the function is defaulted outside the class, we just
4451 give the synthesis error. */
4452 error ("%q+D declared to take const reference, but implicit "
4453 "declaration would take non-const", fn);
4454 else if (imp_const_p && !fn_const_p)
4455 error ("%q+D declared to take non-const reference cannot be "
4456 "defaulted in the class body", fn);
4458 defaulted_late_check (fn);
4461 if (LAMBDA_TYPE_P (t))
4463 /* "The closure type associated with a lambda-expression has a deleted
4464 default constructor and a deleted copy assignment operator." */
4465 TYPE_NEEDS_CONSTRUCTING (t) = 1;
4466 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 0;
4467 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 0;
4468 TYPE_HAS_ASSIGN_REF (t) = 0;
4469 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 0;
4471 /* "This class type is not an aggregate." */
4472 CLASSTYPE_NON_AGGREGATE (t) = 1;
4475 /* Create the in-charge and not-in-charge variants of constructors
4477 clone_constructors_and_destructors (t);
4479 /* Process the using-declarations. */
4480 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4481 handle_using_decl (TREE_VALUE (access_decls), t);
4483 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4484 finish_struct_methods (t);
4486 /* Figure out whether or not we will need a cookie when dynamically
4487 allocating an array of this type. */
4488 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4489 = type_requires_array_cookie (t);
4492 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4493 accordingly. If a new vfield was created (because T doesn't have a
4494 primary base class), then the newly created field is returned. It
4495 is not added to the TYPE_FIELDS list; it is the caller's
4496 responsibility to do that. Accumulate declared virtual functions
4500 create_vtable_ptr (tree t, tree* virtuals_p)
4504 /* Collect the virtual functions declared in T. */
4505 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4506 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4507 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4509 tree new_virtual = make_node (TREE_LIST);
4511 BV_FN (new_virtual) = fn;
4512 BV_DELTA (new_virtual) = integer_zero_node;
4513 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4515 TREE_CHAIN (new_virtual) = *virtuals_p;
4516 *virtuals_p = new_virtual;
4519 /* If we couldn't find an appropriate base class, create a new field
4520 here. Even if there weren't any new virtual functions, we might need a
4521 new virtual function table if we're supposed to include vptrs in
4522 all classes that need them. */
4523 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4525 /* We build this decl with vtbl_ptr_type_node, which is a
4526 `vtable_entry_type*'. It might seem more precise to use
4527 `vtable_entry_type (*)[N]' where N is the number of virtual
4528 functions. However, that would require the vtable pointer in
4529 base classes to have a different type than the vtable pointer
4530 in derived classes. We could make that happen, but that
4531 still wouldn't solve all the problems. In particular, the
4532 type-based alias analysis code would decide that assignments
4533 to the base class vtable pointer can't alias assignments to
4534 the derived class vtable pointer, since they have different
4535 types. Thus, in a derived class destructor, where the base
4536 class constructor was inlined, we could generate bad code for
4537 setting up the vtable pointer.
4539 Therefore, we use one type for all vtable pointers. We still
4540 use a type-correct type; it's just doesn't indicate the array
4541 bounds. That's better than using `void*' or some such; it's
4542 cleaner, and it let's the alias analysis code know that these
4543 stores cannot alias stores to void*! */
4546 field = build_decl (input_location,
4547 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4548 DECL_VIRTUAL_P (field) = 1;
4549 DECL_ARTIFICIAL (field) = 1;
4550 DECL_FIELD_CONTEXT (field) = t;
4551 DECL_FCONTEXT (field) = t;
4553 TYPE_VFIELD (t) = field;
4555 /* This class is non-empty. */
4556 CLASSTYPE_EMPTY_P (t) = 0;
4564 /* Add OFFSET to all base types of BINFO which is a base in the
4565 hierarchy dominated by T.
4567 OFFSET, which is a type offset, is number of bytes. */
4570 propagate_binfo_offsets (tree binfo, tree offset)
4576 /* Update BINFO's offset. */
4577 BINFO_OFFSET (binfo)
4578 = convert (sizetype,
4579 size_binop (PLUS_EXPR,
4580 convert (ssizetype, BINFO_OFFSET (binfo)),
4583 /* Find the primary base class. */
4584 primary_binfo = get_primary_binfo (binfo);
4586 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4587 propagate_binfo_offsets (primary_binfo, offset);
4589 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4591 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4593 /* Don't do the primary base twice. */
4594 if (base_binfo == primary_binfo)
4597 if (BINFO_VIRTUAL_P (base_binfo))
4600 propagate_binfo_offsets (base_binfo, offset);
4604 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4605 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4606 empty subobjects of T. */
4609 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4613 bool first_vbase = true;
4616 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4619 if (!abi_version_at_least(2))
4621 /* In G++ 3.2, we incorrectly rounded the size before laying out
4622 the virtual bases. */
4623 finish_record_layout (rli, /*free_p=*/false);
4624 #ifdef STRUCTURE_SIZE_BOUNDARY
4625 /* Packed structures don't need to have minimum size. */
4626 if (! TYPE_PACKED (t))
4627 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4629 rli->offset = TYPE_SIZE_UNIT (t);
4630 rli->bitpos = bitsize_zero_node;
4631 rli->record_align = TYPE_ALIGN (t);
4634 /* Find the last field. The artificial fields created for virtual
4635 bases will go after the last extant field to date. */
4636 next_field = &TYPE_FIELDS (t);
4638 next_field = &TREE_CHAIN (*next_field);
4640 /* Go through the virtual bases, allocating space for each virtual
4641 base that is not already a primary base class. These are
4642 allocated in inheritance graph order. */
4643 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4645 if (!BINFO_VIRTUAL_P (vbase))
4648 if (!BINFO_PRIMARY_P (vbase))
4650 tree basetype = TREE_TYPE (vbase);
4652 /* This virtual base is not a primary base of any class in the
4653 hierarchy, so we have to add space for it. */
4654 next_field = build_base_field (rli, vbase,
4655 offsets, next_field);
4657 /* If the first virtual base might have been placed at a
4658 lower address, had we started from CLASSTYPE_SIZE, rather
4659 than TYPE_SIZE, issue a warning. There can be both false
4660 positives and false negatives from this warning in rare
4661 cases; to deal with all the possibilities would probably
4662 require performing both layout algorithms and comparing
4663 the results which is not particularly tractable. */
4667 (size_binop (CEIL_DIV_EXPR,
4668 round_up_loc (input_location,
4670 CLASSTYPE_ALIGN (basetype)),
4672 BINFO_OFFSET (vbase))))
4674 "offset of virtual base %qT is not ABI-compliant and "
4675 "may change in a future version of GCC",
4678 first_vbase = false;
4683 /* Returns the offset of the byte just past the end of the base class
4687 end_of_base (tree binfo)
4691 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
4692 size = TYPE_SIZE_UNIT (char_type_node);
4693 else if (is_empty_class (BINFO_TYPE (binfo)))
4694 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4695 allocate some space for it. It cannot have virtual bases, so
4696 TYPE_SIZE_UNIT is fine. */
4697 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4699 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4701 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4704 /* Returns the offset of the byte just past the end of the base class
4705 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4706 only non-virtual bases are included. */
4709 end_of_class (tree t, int include_virtuals_p)
4711 tree result = size_zero_node;
4712 VEC(tree,gc) *vbases;
4718 for (binfo = TYPE_BINFO (t), i = 0;
4719 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4721 if (!include_virtuals_p
4722 && BINFO_VIRTUAL_P (base_binfo)
4723 && (!BINFO_PRIMARY_P (base_binfo)
4724 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4727 offset = end_of_base (base_binfo);
4728 if (INT_CST_LT_UNSIGNED (result, offset))
4732 /* G++ 3.2 did not check indirect virtual bases. */
4733 if (abi_version_at_least (2) && include_virtuals_p)
4734 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4735 VEC_iterate (tree, vbases, i, base_binfo); i++)
4737 offset = end_of_base (base_binfo);
4738 if (INT_CST_LT_UNSIGNED (result, offset))
4745 /* Warn about bases of T that are inaccessible because they are
4746 ambiguous. For example:
4749 struct T : public S {};
4750 struct U : public S, public T {};
4752 Here, `(S*) new U' is not allowed because there are two `S'
4756 warn_about_ambiguous_bases (tree t)
4759 VEC(tree,gc) *vbases;
4764 /* If there are no repeated bases, nothing can be ambiguous. */
4765 if (!CLASSTYPE_REPEATED_BASE_P (t))
4768 /* Check direct bases. */
4769 for (binfo = TYPE_BINFO (t), i = 0;
4770 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4772 basetype = BINFO_TYPE (base_binfo);
4774 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4775 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4779 /* Check for ambiguous virtual bases. */
4781 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4782 VEC_iterate (tree, vbases, i, binfo); i++)
4784 basetype = BINFO_TYPE (binfo);
4786 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4787 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4792 /* Compare two INTEGER_CSTs K1 and K2. */
4795 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4797 return tree_int_cst_compare ((tree) k1, (tree) k2);
4800 /* Increase the size indicated in RLI to account for empty classes
4801 that are "off the end" of the class. */
4804 include_empty_classes (record_layout_info rli)
4809 /* It might be the case that we grew the class to allocate a
4810 zero-sized base class. That won't be reflected in RLI, yet,
4811 because we are willing to overlay multiple bases at the same
4812 offset. However, now we need to make sure that RLI is big enough
4813 to reflect the entire class. */
4814 eoc = end_of_class (rli->t,
4815 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4816 rli_size = rli_size_unit_so_far (rli);
4817 if (TREE_CODE (rli_size) == INTEGER_CST
4818 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4820 if (!abi_version_at_least (2))
4821 /* In version 1 of the ABI, the size of a class that ends with
4822 a bitfield was not rounded up to a whole multiple of a
4823 byte. Because rli_size_unit_so_far returns only the number
4824 of fully allocated bytes, any extra bits were not included
4826 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4828 /* The size should have been rounded to a whole byte. */
4829 gcc_assert (tree_int_cst_equal
4830 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4832 = size_binop (PLUS_EXPR,
4834 size_binop (MULT_EXPR,
4835 convert (bitsizetype,
4836 size_binop (MINUS_EXPR,
4838 bitsize_int (BITS_PER_UNIT)));
4839 normalize_rli (rli);
4843 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4844 BINFO_OFFSETs for all of the base-classes. Position the vtable
4845 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4848 layout_class_type (tree t, tree *virtuals_p)
4850 tree non_static_data_members;
4853 record_layout_info rli;
4854 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4855 types that appear at that offset. */
4856 splay_tree empty_base_offsets;
4857 /* True if the last field layed out was a bit-field. */
4858 bool last_field_was_bitfield = false;
4859 /* The location at which the next field should be inserted. */
4861 /* T, as a base class. */
4864 /* Keep track of the first non-static data member. */
4865 non_static_data_members = TYPE_FIELDS (t);
4867 /* Start laying out the record. */
4868 rli = start_record_layout (t);
4870 /* Mark all the primary bases in the hierarchy. */
4871 determine_primary_bases (t);
4873 /* Create a pointer to our virtual function table. */
4874 vptr = create_vtable_ptr (t, virtuals_p);
4876 /* The vptr is always the first thing in the class. */
4879 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4880 TYPE_FIELDS (t) = vptr;
4881 next_field = &TREE_CHAIN (vptr);
4882 place_field (rli, vptr);
4885 next_field = &TYPE_FIELDS (t);
4887 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4888 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4890 build_base_fields (rli, empty_base_offsets, next_field);
4892 /* Layout the non-static data members. */
4893 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4898 /* We still pass things that aren't non-static data members to
4899 the back end, in case it wants to do something with them. */
4900 if (TREE_CODE (field) != FIELD_DECL)
4902 place_field (rli, field);
4903 /* If the static data member has incomplete type, keep track
4904 of it so that it can be completed later. (The handling
4905 of pending statics in finish_record_layout is
4906 insufficient; consider:
4909 struct S2 { static S1 s1; };
4911 At this point, finish_record_layout will be called, but
4912 S1 is still incomplete.) */
4913 if (TREE_CODE (field) == VAR_DECL)
4915 maybe_register_incomplete_var (field);
4916 /* The visibility of static data members is determined
4917 at their point of declaration, not their point of
4919 determine_visibility (field);
4924 type = TREE_TYPE (field);
4925 if (type == error_mark_node)
4928 padding = NULL_TREE;
4930 /* If this field is a bit-field whose width is greater than its
4931 type, then there are some special rules for allocating
4933 if (DECL_C_BIT_FIELD (field)
4934 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4938 bool was_unnamed_p = false;
4939 /* We must allocate the bits as if suitably aligned for the
4940 longest integer type that fits in this many bits. type
4941 of the field. Then, we are supposed to use the left over
4942 bits as additional padding. */
4943 for (itk = itk_char; itk != itk_none; ++itk)
4944 if (INT_CST_LT (DECL_SIZE (field),
4945 TYPE_SIZE (integer_types[itk])))
4948 /* ITK now indicates a type that is too large for the
4949 field. We have to back up by one to find the largest
4951 integer_type = integer_types[itk - 1];
4953 /* Figure out how much additional padding is required. GCC
4954 3.2 always created a padding field, even if it had zero
4956 if (!abi_version_at_least (2)
4957 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4959 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4960 /* In a union, the padding field must have the full width
4961 of the bit-field; all fields start at offset zero. */
4962 padding = DECL_SIZE (field);
4965 if (TREE_CODE (t) == UNION_TYPE)
4966 warning (OPT_Wabi, "size assigned to %qT may not be "
4967 "ABI-compliant and may change in a future "
4970 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4971 TYPE_SIZE (integer_type));
4974 #ifdef PCC_BITFIELD_TYPE_MATTERS
4975 /* An unnamed bitfield does not normally affect the
4976 alignment of the containing class on a target where
4977 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4978 make any exceptions for unnamed bitfields when the
4979 bitfields are longer than their types. Therefore, we
4980 temporarily give the field a name. */
4981 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4983 was_unnamed_p = true;
4984 DECL_NAME (field) = make_anon_name ();
4987 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4988 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4989 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4990 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4991 empty_base_offsets);
4993 DECL_NAME (field) = NULL_TREE;
4994 /* Now that layout has been performed, set the size of the
4995 field to the size of its declared type; the rest of the
4996 field is effectively invisible. */
4997 DECL_SIZE (field) = TYPE_SIZE (type);
4998 /* We must also reset the DECL_MODE of the field. */
4999 if (abi_version_at_least (2))
5000 DECL_MODE (field) = TYPE_MODE (type);
5002 && DECL_MODE (field) != TYPE_MODE (type))
5003 /* Versions of G++ before G++ 3.4 did not reset the
5006 "the offset of %qD may not be ABI-compliant and may "
5007 "change in a future version of GCC", field);
5010 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5011 empty_base_offsets);
5013 /* Remember the location of any empty classes in FIELD. */
5014 if (abi_version_at_least (2))
5015 record_subobject_offsets (TREE_TYPE (field),
5016 byte_position(field),
5018 /*is_data_member=*/true);
5020 /* If a bit-field does not immediately follow another bit-field,
5021 and yet it starts in the middle of a byte, we have failed to
5022 comply with the ABI. */
5024 && DECL_C_BIT_FIELD (field)
5025 /* The TREE_NO_WARNING flag gets set by Objective-C when
5026 laying out an Objective-C class. The ObjC ABI differs
5027 from the C++ ABI, and so we do not want a warning
5029 && !TREE_NO_WARNING (field)
5030 && !last_field_was_bitfield
5031 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5032 DECL_FIELD_BIT_OFFSET (field),
5033 bitsize_unit_node)))
5034 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5035 "change in a future version of GCC", field);
5037 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5038 offset of the field. */
5040 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5041 byte_position (field))
5042 && contains_empty_class_p (TREE_TYPE (field)))
5043 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5044 "classes to be placed at different locations in a "
5045 "future version of GCC", field);
5047 /* The middle end uses the type of expressions to determine the
5048 possible range of expression values. In order to optimize
5049 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5050 must be made aware of the width of "i", via its type.
5052 Because C++ does not have integer types of arbitrary width,
5053 we must (for the purposes of the front end) convert from the
5054 type assigned here to the declared type of the bitfield
5055 whenever a bitfield expression is used as an rvalue.
5056 Similarly, when assigning a value to a bitfield, the value
5057 must be converted to the type given the bitfield here. */
5058 if (DECL_C_BIT_FIELD (field))
5060 unsigned HOST_WIDE_INT width;
5061 tree ftype = TREE_TYPE (field);
5062 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5063 if (width != TYPE_PRECISION (ftype))
5066 = c_build_bitfield_integer_type (width,
5067 TYPE_UNSIGNED (ftype));
5069 = cp_build_qualified_type (TREE_TYPE (field),
5070 TYPE_QUALS (ftype));
5074 /* If we needed additional padding after this field, add it
5080 padding_field = build_decl (input_location,
5084 DECL_BIT_FIELD (padding_field) = 1;
5085 DECL_SIZE (padding_field) = padding;
5086 DECL_CONTEXT (padding_field) = t;
5087 DECL_ARTIFICIAL (padding_field) = 1;
5088 DECL_IGNORED_P (padding_field) = 1;
5089 layout_nonempty_base_or_field (rli, padding_field,
5091 empty_base_offsets);
5094 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5097 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5099 /* Make sure that we are on a byte boundary so that the size of
5100 the class without virtual bases will always be a round number
5102 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5103 normalize_rli (rli);
5106 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5108 if (!abi_version_at_least (2))
5109 include_empty_classes(rli);
5111 /* Delete all zero-width bit-fields from the list of fields. Now
5112 that the type is laid out they are no longer important. */
5113 remove_zero_width_bit_fields (t);
5115 /* Create the version of T used for virtual bases. We do not use
5116 make_class_type for this version; this is an artificial type. For
5117 a POD type, we just reuse T. */
5118 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5120 base_t = make_node (TREE_CODE (t));
5122 /* Set the size and alignment for the new type. In G++ 3.2, all
5123 empty classes were considered to have size zero when used as
5125 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5127 TYPE_SIZE (base_t) = bitsize_zero_node;
5128 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5129 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5131 "layout of classes derived from empty class %qT "
5132 "may change in a future version of GCC",
5139 /* If the ABI version is not at least two, and the last
5140 field was a bit-field, RLI may not be on a byte
5141 boundary. In particular, rli_size_unit_so_far might
5142 indicate the last complete byte, while rli_size_so_far
5143 indicates the total number of bits used. Therefore,
5144 rli_size_so_far, rather than rli_size_unit_so_far, is
5145 used to compute TYPE_SIZE_UNIT. */
5146 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5147 TYPE_SIZE_UNIT (base_t)
5148 = size_binop (MAX_EXPR,
5150 size_binop (CEIL_DIV_EXPR,
5151 rli_size_so_far (rli),
5152 bitsize_int (BITS_PER_UNIT))),
5155 = size_binop (MAX_EXPR,
5156 rli_size_so_far (rli),
5157 size_binop (MULT_EXPR,
5158 convert (bitsizetype, eoc),
5159 bitsize_int (BITS_PER_UNIT)));
5161 TYPE_ALIGN (base_t) = rli->record_align;
5162 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5164 /* Copy the fields from T. */
5165 next_field = &TYPE_FIELDS (base_t);
5166 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5167 if (TREE_CODE (field) == FIELD_DECL)
5169 *next_field = build_decl (input_location,
5173 DECL_CONTEXT (*next_field) = base_t;
5174 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5175 DECL_FIELD_BIT_OFFSET (*next_field)
5176 = DECL_FIELD_BIT_OFFSET (field);
5177 DECL_SIZE (*next_field) = DECL_SIZE (field);
5178 DECL_MODE (*next_field) = DECL_MODE (field);
5179 next_field = &TREE_CHAIN (*next_field);
5182 /* Record the base version of the type. */
5183 CLASSTYPE_AS_BASE (t) = base_t;
5184 TYPE_CONTEXT (base_t) = t;
5187 CLASSTYPE_AS_BASE (t) = t;
5189 /* Every empty class contains an empty class. */
5190 if (CLASSTYPE_EMPTY_P (t))
5191 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5193 /* Set the TYPE_DECL for this type to contain the right
5194 value for DECL_OFFSET, so that we can use it as part
5195 of a COMPONENT_REF for multiple inheritance. */
5196 layout_decl (TYPE_MAIN_DECL (t), 0);
5198 /* Now fix up any virtual base class types that we left lying
5199 around. We must get these done before we try to lay out the
5200 virtual function table. As a side-effect, this will remove the
5201 base subobject fields. */
5202 layout_virtual_bases (rli, empty_base_offsets);
5204 /* Make sure that empty classes are reflected in RLI at this
5206 include_empty_classes(rli);
5208 /* Make sure not to create any structures with zero size. */
5209 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5211 build_decl (input_location,
5212 FIELD_DECL, NULL_TREE, char_type_node));
5214 /* Let the back end lay out the type. */
5215 finish_record_layout (rli, /*free_p=*/true);
5217 /* Warn about bases that can't be talked about due to ambiguity. */
5218 warn_about_ambiguous_bases (t);
5220 /* Now that we're done with layout, give the base fields the real types. */
5221 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5222 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5223 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5226 splay_tree_delete (empty_base_offsets);
5228 if (CLASSTYPE_EMPTY_P (t)
5229 && tree_int_cst_lt (sizeof_biggest_empty_class,
5230 TYPE_SIZE_UNIT (t)))
5231 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5234 /* Determine the "key method" for the class type indicated by TYPE,
5235 and set CLASSTYPE_KEY_METHOD accordingly. */
5238 determine_key_method (tree type)
5242 if (TYPE_FOR_JAVA (type)
5243 || processing_template_decl
5244 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5245 || CLASSTYPE_INTERFACE_KNOWN (type))
5248 /* The key method is the first non-pure virtual function that is not
5249 inline at the point of class definition. On some targets the
5250 key function may not be inline; those targets should not call
5251 this function until the end of the translation unit. */
5252 for (method = TYPE_METHODS (type); method != NULL_TREE;
5253 method = TREE_CHAIN (method))
5254 if (DECL_VINDEX (method) != NULL_TREE
5255 && ! DECL_DECLARED_INLINE_P (method)
5256 && ! DECL_PURE_VIRTUAL_P (method))
5258 CLASSTYPE_KEY_METHOD (type) = method;
5265 /* Perform processing required when the definition of T (a class type)
5269 finish_struct_1 (tree t)
5272 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5273 tree virtuals = NULL_TREE;
5276 if (COMPLETE_TYPE_P (t))
5278 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5279 error ("redefinition of %q#T", t);
5284 /* If this type was previously laid out as a forward reference,
5285 make sure we lay it out again. */
5286 TYPE_SIZE (t) = NULL_TREE;
5287 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5289 /* Make assumptions about the class; we'll reset the flags if
5291 CLASSTYPE_EMPTY_P (t) = 1;
5292 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5293 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5295 /* Do end-of-class semantic processing: checking the validity of the
5296 bases and members and add implicitly generated methods. */
5297 check_bases_and_members (t);
5299 /* Find the key method. */
5300 if (TYPE_CONTAINS_VPTR_P (t))
5302 /* The Itanium C++ ABI permits the key method to be chosen when
5303 the class is defined -- even though the key method so
5304 selected may later turn out to be an inline function. On
5305 some systems (such as ARM Symbian OS) the key method cannot
5306 be determined until the end of the translation unit. On such
5307 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5308 will cause the class to be added to KEYED_CLASSES. Then, in
5309 finish_file we will determine the key method. */
5310 if (targetm.cxx.key_method_may_be_inline ())
5311 determine_key_method (t);
5313 /* If a polymorphic class has no key method, we may emit the vtable
5314 in every translation unit where the class definition appears. */
5315 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5316 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5319 /* Layout the class itself. */
5320 layout_class_type (t, &virtuals);
5321 if (CLASSTYPE_AS_BASE (t) != t)
5322 /* We use the base type for trivial assignments, and hence it
5324 compute_record_mode (CLASSTYPE_AS_BASE (t));
5326 virtuals = modify_all_vtables (t, nreverse (virtuals));
5328 /* If necessary, create the primary vtable for this class. */
5329 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5331 /* We must enter these virtuals into the table. */
5332 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5333 build_primary_vtable (NULL_TREE, t);
5334 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5335 /* Here we know enough to change the type of our virtual
5336 function table, but we will wait until later this function. */
5337 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5340 if (TYPE_CONTAINS_VPTR_P (t))
5345 if (BINFO_VTABLE (TYPE_BINFO (t)))
5346 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5347 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5348 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5350 /* Add entries for virtual functions introduced by this class. */
5351 BINFO_VIRTUALS (TYPE_BINFO (t))
5352 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5354 /* Set DECL_VINDEX for all functions declared in this class. */
5355 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5357 fn = TREE_CHAIN (fn),
5358 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5359 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5361 tree fndecl = BV_FN (fn);
5363 if (DECL_THUNK_P (fndecl))
5364 /* A thunk. We should never be calling this entry directly
5365 from this vtable -- we'd use the entry for the non
5366 thunk base function. */
5367 DECL_VINDEX (fndecl) = NULL_TREE;
5368 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5369 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5373 finish_struct_bits (t);
5375 /* Complete the rtl for any static member objects of the type we're
5377 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5378 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5379 && TREE_TYPE (x) != error_mark_node
5380 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5381 DECL_MODE (x) = TYPE_MODE (t);
5383 /* Done with FIELDS...now decide whether to sort these for
5384 faster lookups later.
5386 We use a small number because most searches fail (succeeding
5387 ultimately as the search bores through the inheritance
5388 hierarchy), and we want this failure to occur quickly. */
5390 n_fields = count_fields (TYPE_FIELDS (t));
5393 struct sorted_fields_type *field_vec = GGC_NEWVAR
5394 (struct sorted_fields_type,
5395 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5396 field_vec->len = n_fields;
5397 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5398 qsort (field_vec->elts, n_fields, sizeof (tree),
5400 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
5403 /* Complain if one of the field types requires lower visibility. */
5404 constrain_class_visibility (t);
5406 /* Make the rtl for any new vtables we have created, and unmark
5407 the base types we marked. */
5410 /* Build the VTT for T. */
5413 /* This warning does not make sense for Java classes, since they
5414 cannot have destructors. */
5415 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5419 dtor = CLASSTYPE_DESTRUCTORS (t);
5420 if (/* An implicitly declared destructor is always public. And,
5421 if it were virtual, we would have created it by now. */
5423 || (!DECL_VINDEX (dtor)
5424 && (/* public non-virtual */
5425 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5426 || (/* non-public non-virtual with friends */
5427 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5428 && (CLASSTYPE_FRIEND_CLASSES (t)
5429 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5430 warning (OPT_Wnon_virtual_dtor,
5431 "%q#T has virtual functions and accessible"
5432 " non-virtual destructor", t);
5437 if (warn_overloaded_virtual)
5440 /* Class layout, assignment of virtual table slots, etc., is now
5441 complete. Give the back end a chance to tweak the visibility of
5442 the class or perform any other required target modifications. */
5443 targetm.cxx.adjust_class_at_definition (t);
5445 maybe_suppress_debug_info (t);
5447 dump_class_hierarchy (t);
5449 /* Finish debugging output for this type. */
5450 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5453 /* When T was built up, the member declarations were added in reverse
5454 order. Rearrange them to declaration order. */
5457 unreverse_member_declarations (tree t)
5463 /* The following lists are all in reverse order. Put them in
5464 declaration order now. */
5465 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5466 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5468 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5469 reverse order, so we can't just use nreverse. */
5471 for (x = TYPE_FIELDS (t);
5472 x && TREE_CODE (x) != TYPE_DECL;
5475 next = TREE_CHAIN (x);
5476 TREE_CHAIN (x) = prev;
5481 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5483 TYPE_FIELDS (t) = prev;
5488 finish_struct (tree t, tree attributes)
5490 location_t saved_loc = input_location;
5492 /* Now that we've got all the field declarations, reverse everything
5494 unreverse_member_declarations (t);
5496 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5498 /* Nadger the current location so that diagnostics point to the start of
5499 the struct, not the end. */
5500 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5502 if (processing_template_decl)
5506 finish_struct_methods (t);
5507 TYPE_SIZE (t) = bitsize_zero_node;
5508 TYPE_SIZE_UNIT (t) = size_zero_node;
5510 /* We need to emit an error message if this type was used as a parameter
5511 and it is an abstract type, even if it is a template. We construct
5512 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5513 account and we call complete_vars with this type, which will check
5514 the PARM_DECLS. Note that while the type is being defined,
5515 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5516 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5517 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5518 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5519 if (DECL_PURE_VIRTUAL_P (x))
5520 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5523 /* Remember current #pragma pack value. */
5524 TYPE_PRECISION (t) = maximum_field_alignment;
5527 finish_struct_1 (t);
5529 input_location = saved_loc;
5531 TYPE_BEING_DEFINED (t) = 0;
5533 if (current_class_type)
5536 error ("trying to finish struct, but kicked out due to previous parse errors");
5538 if (processing_template_decl && at_function_scope_p ())
5539 add_stmt (build_min (TAG_DEFN, t));
5544 /* Return the dynamic type of INSTANCE, if known.
5545 Used to determine whether the virtual function table is needed
5548 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5549 of our knowledge of its type. *NONNULL should be initialized
5550 before this function is called. */
5553 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5555 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5557 switch (TREE_CODE (instance))
5560 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5563 return RECUR (TREE_OPERAND (instance, 0));
5566 /* This is a call to a constructor, hence it's never zero. */
5567 if (TREE_HAS_CONSTRUCTOR (instance))
5571 return TREE_TYPE (instance);
5576 /* This is a call to a constructor, hence it's never zero. */
5577 if (TREE_HAS_CONSTRUCTOR (instance))
5581 return TREE_TYPE (instance);
5583 return RECUR (TREE_OPERAND (instance, 0));
5585 case POINTER_PLUS_EXPR:
5588 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5589 return RECUR (TREE_OPERAND (instance, 0));
5590 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5591 /* Propagate nonnull. */
5592 return RECUR (TREE_OPERAND (instance, 0));
5597 return RECUR (TREE_OPERAND (instance, 0));
5600 instance = TREE_OPERAND (instance, 0);
5603 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5604 with a real object -- given &p->f, p can still be null. */
5605 tree t = get_base_address (instance);
5606 /* ??? Probably should check DECL_WEAK here. */
5607 if (t && DECL_P (t))
5610 return RECUR (instance);
5613 /* If this component is really a base class reference, then the field
5614 itself isn't definitive. */
5615 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5616 return RECUR (TREE_OPERAND (instance, 0));
5617 return RECUR (TREE_OPERAND (instance, 1));
5621 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5622 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
5626 return TREE_TYPE (TREE_TYPE (instance));
5628 /* fall through... */
5632 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
5636 return TREE_TYPE (instance);
5638 else if (instance == current_class_ptr)
5643 /* if we're in a ctor or dtor, we know our type. */
5644 if (DECL_LANG_SPECIFIC (current_function_decl)
5645 && (DECL_CONSTRUCTOR_P (current_function_decl)
5646 || DECL_DESTRUCTOR_P (current_function_decl)))
5650 return TREE_TYPE (TREE_TYPE (instance));
5653 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5655 /* We only need one hash table because it is always left empty. */
5658 ht = htab_create (37,
5663 /* Reference variables should be references to objects. */
5667 /* Enter the INSTANCE in a table to prevent recursion; a
5668 variable's initializer may refer to the variable
5670 if (TREE_CODE (instance) == VAR_DECL
5671 && DECL_INITIAL (instance)
5672 && !htab_find (ht, instance))
5677 slot = htab_find_slot (ht, instance, INSERT);
5679 type = RECUR (DECL_INITIAL (instance));
5680 htab_remove_elt (ht, instance);
5693 /* Return nonzero if the dynamic type of INSTANCE is known, and
5694 equivalent to the static type. We also handle the case where
5695 INSTANCE is really a pointer. Return negative if this is a
5696 ctor/dtor. There the dynamic type is known, but this might not be
5697 the most derived base of the original object, and hence virtual
5698 bases may not be layed out according to this type.
5700 Used to determine whether the virtual function table is needed
5703 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5704 of our knowledge of its type. *NONNULL should be initialized
5705 before this function is called. */
5708 resolves_to_fixed_type_p (tree instance, int* nonnull)
5710 tree t = TREE_TYPE (instance);
5712 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5713 if (fixed == NULL_TREE)
5715 if (POINTER_TYPE_P (t))
5717 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5719 return cdtorp ? -1 : 1;
5724 init_class_processing (void)
5726 current_class_depth = 0;
5727 current_class_stack_size = 10;
5729 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5730 local_classes = VEC_alloc (tree, gc, 8);
5731 sizeof_biggest_empty_class = size_zero_node;
5733 ridpointers[(int) RID_PUBLIC] = access_public_node;
5734 ridpointers[(int) RID_PRIVATE] = access_private_node;
5735 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5738 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5741 restore_class_cache (void)
5745 /* We are re-entering the same class we just left, so we don't
5746 have to search the whole inheritance matrix to find all the
5747 decls to bind again. Instead, we install the cached
5748 class_shadowed list and walk through it binding names. */
5749 push_binding_level (previous_class_level);
5750 class_binding_level = previous_class_level;
5751 /* Restore IDENTIFIER_TYPE_VALUE. */
5752 for (type = class_binding_level->type_shadowed;
5754 type = TREE_CHAIN (type))
5755 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5758 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5759 appropriate for TYPE.
5761 So that we may avoid calls to lookup_name, we cache the _TYPE
5762 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5764 For multiple inheritance, we perform a two-pass depth-first search
5765 of the type lattice. */
5768 pushclass (tree type)
5770 class_stack_node_t csn;
5772 type = TYPE_MAIN_VARIANT (type);
5774 /* Make sure there is enough room for the new entry on the stack. */
5775 if (current_class_depth + 1 >= current_class_stack_size)
5777 current_class_stack_size *= 2;
5779 = XRESIZEVEC (struct class_stack_node, current_class_stack,
5780 current_class_stack_size);
5783 /* Insert a new entry on the class stack. */
5784 csn = current_class_stack + current_class_depth;
5785 csn->name = current_class_name;
5786 csn->type = current_class_type;
5787 csn->access = current_access_specifier;
5788 csn->names_used = 0;
5790 current_class_depth++;
5792 /* Now set up the new type. */
5793 current_class_name = TYPE_NAME (type);
5794 if (TREE_CODE (current_class_name) == TYPE_DECL)
5795 current_class_name = DECL_NAME (current_class_name);
5796 current_class_type = type;
5798 /* By default, things in classes are private, while things in
5799 structures or unions are public. */
5800 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5801 ? access_private_node
5802 : access_public_node);
5804 if (previous_class_level
5805 && type != previous_class_level->this_entity
5806 && current_class_depth == 1)
5808 /* Forcibly remove any old class remnants. */
5809 invalidate_class_lookup_cache ();
5812 if (!previous_class_level
5813 || type != previous_class_level->this_entity
5814 || current_class_depth > 1)
5817 restore_class_cache ();
5820 /* When we exit a toplevel class scope, we save its binding level so
5821 that we can restore it quickly. Here, we've entered some other
5822 class, so we must invalidate our cache. */
5825 invalidate_class_lookup_cache (void)
5827 previous_class_level = NULL;
5830 /* Get out of the current class scope. If we were in a class scope
5831 previously, that is the one popped to. */
5838 current_class_depth--;
5839 current_class_name = current_class_stack[current_class_depth].name;
5840 current_class_type = current_class_stack[current_class_depth].type;
5841 current_access_specifier = current_class_stack[current_class_depth].access;
5842 if (current_class_stack[current_class_depth].names_used)
5843 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5846 /* Mark the top of the class stack as hidden. */
5849 push_class_stack (void)
5851 if (current_class_depth)
5852 ++current_class_stack[current_class_depth - 1].hidden;
5855 /* Mark the top of the class stack as un-hidden. */
5858 pop_class_stack (void)
5860 if (current_class_depth)
5861 --current_class_stack[current_class_depth - 1].hidden;
5864 /* Returns 1 if the class type currently being defined is either T or
5865 a nested type of T. */
5868 currently_open_class (tree t)
5872 if (!CLASS_TYPE_P (t))
5875 t = TYPE_MAIN_VARIANT (t);
5877 /* We start looking from 1 because entry 0 is from global scope,
5879 for (i = current_class_depth; i > 0; --i)
5882 if (i == current_class_depth)
5883 c = current_class_type;
5886 if (current_class_stack[i].hidden)
5888 c = current_class_stack[i].type;
5892 if (same_type_p (c, t))
5898 /* If either current_class_type or one of its enclosing classes are derived
5899 from T, return the appropriate type. Used to determine how we found
5900 something via unqualified lookup. */
5903 currently_open_derived_class (tree t)
5907 /* The bases of a dependent type are unknown. */
5908 if (dependent_type_p (t))
5911 if (!current_class_type)
5914 if (DERIVED_FROM_P (t, current_class_type))
5915 return current_class_type;
5917 for (i = current_class_depth - 1; i > 0; --i)
5919 if (current_class_stack[i].hidden)
5921 if (DERIVED_FROM_P (t, current_class_stack[i].type))
5922 return current_class_stack[i].type;
5928 /* When entering a class scope, all enclosing class scopes' names with
5929 static meaning (static variables, static functions, types and
5930 enumerators) have to be visible. This recursive function calls
5931 pushclass for all enclosing class contexts until global or a local
5932 scope is reached. TYPE is the enclosed class. */
5935 push_nested_class (tree type)
5937 /* A namespace might be passed in error cases, like A::B:C. */
5938 if (type == NULL_TREE
5939 || !CLASS_TYPE_P (type))
5942 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
5947 /* Undoes a push_nested_class call. */
5950 pop_nested_class (void)
5952 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5955 if (context && CLASS_TYPE_P (context))
5956 pop_nested_class ();
5959 /* Returns the number of extern "LANG" blocks we are nested within. */
5962 current_lang_depth (void)
5964 return VEC_length (tree, current_lang_base);
5967 /* Set global variables CURRENT_LANG_NAME to appropriate value
5968 so that behavior of name-mangling machinery is correct. */
5971 push_lang_context (tree name)
5973 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
5975 if (name == lang_name_cplusplus)
5977 current_lang_name = name;
5979 else if (name == lang_name_java)
5981 current_lang_name = name;
5982 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5983 (See record_builtin_java_type in decl.c.) However, that causes
5984 incorrect debug entries if these types are actually used.
5985 So we re-enable debug output after extern "Java". */
5986 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
5987 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
5988 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
5989 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
5990 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
5991 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
5992 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
5993 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
5995 else if (name == lang_name_c)
5997 current_lang_name = name;
6000 error ("language string %<\"%E\"%> not recognized", name);
6003 /* Get out of the current language scope. */
6006 pop_lang_context (void)
6008 current_lang_name = VEC_pop (tree, current_lang_base);
6011 /* Type instantiation routines. */
6013 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6014 matches the TARGET_TYPE. If there is no satisfactory match, return
6015 error_mark_node, and issue an error & warning messages under
6016 control of FLAGS. Permit pointers to member function if FLAGS
6017 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6018 a template-id, and EXPLICIT_TARGS are the explicitly provided
6021 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6022 is the base path used to reference those member functions. If
6023 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6024 resolved to a member function, access checks will be performed and
6025 errors issued if appropriate. */
6028 resolve_address_of_overloaded_function (tree target_type,
6030 tsubst_flags_t flags,
6032 tree explicit_targs,
6035 /* Here's what the standard says:
6039 If the name is a function template, template argument deduction
6040 is done, and if the argument deduction succeeds, the deduced
6041 arguments are used to generate a single template function, which
6042 is added to the set of overloaded functions considered.
6044 Non-member functions and static member functions match targets of
6045 type "pointer-to-function" or "reference-to-function." Nonstatic
6046 member functions match targets of type "pointer-to-member
6047 function;" the function type of the pointer to member is used to
6048 select the member function from the set of overloaded member
6049 functions. If a nonstatic member function is selected, the
6050 reference to the overloaded function name is required to have the
6051 form of a pointer to member as described in 5.3.1.
6053 If more than one function is selected, any template functions in
6054 the set are eliminated if the set also contains a non-template
6055 function, and any given template function is eliminated if the
6056 set contains a second template function that is more specialized
6057 than the first according to the partial ordering rules 14.5.5.2.
6058 After such eliminations, if any, there shall remain exactly one
6059 selected function. */
6062 int is_reference = 0;
6063 /* We store the matches in a TREE_LIST rooted here. The functions
6064 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6065 interoperability with most_specialized_instantiation. */
6066 tree matches = NULL_TREE;
6068 tree target_fn_type;
6070 /* By the time we get here, we should be seeing only real
6071 pointer-to-member types, not the internal POINTER_TYPE to
6072 METHOD_TYPE representation. */
6073 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6074 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6076 gcc_assert (is_overloaded_fn (overload));
6078 /* Check that the TARGET_TYPE is reasonable. */
6079 if (TYPE_PTRFN_P (target_type))
6081 else if (TYPE_PTRMEMFUNC_P (target_type))
6082 /* This is OK, too. */
6084 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6086 /* This is OK, too. This comes from a conversion to reference
6088 target_type = build_reference_type (target_type);
6093 if (flags & tf_error)
6094 error ("cannot resolve overloaded function %qD based on"
6095 " conversion to type %qT",
6096 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6097 return error_mark_node;
6100 /* Non-member functions and static member functions match targets of type
6101 "pointer-to-function" or "reference-to-function." Nonstatic member
6102 functions match targets of type "pointer-to-member-function;" the
6103 function type of the pointer to member is used to select the member
6104 function from the set of overloaded member functions.
6106 So figure out the FUNCTION_TYPE that we want to match against. */
6107 target_fn_type = static_fn_type (target_type);
6109 /* If we can find a non-template function that matches, we can just
6110 use it. There's no point in generating template instantiations
6111 if we're just going to throw them out anyhow. But, of course, we
6112 can only do this when we don't *need* a template function. */
6117 for (fns = overload; fns; fns = OVL_NEXT (fns))
6119 tree fn = OVL_CURRENT (fns);
6121 if (TREE_CODE (fn) == TEMPLATE_DECL)
6122 /* We're not looking for templates just yet. */
6125 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6127 /* We're looking for a non-static member, and this isn't
6128 one, or vice versa. */
6131 /* Ignore functions which haven't been explicitly
6133 if (DECL_ANTICIPATED (fn))
6136 /* See if there's a match. */
6137 if (same_type_p (target_fn_type, static_fn_type (fn)))
6138 matches = tree_cons (fn, NULL_TREE, matches);
6142 /* Now, if we've already got a match (or matches), there's no need
6143 to proceed to the template functions. But, if we don't have a
6144 match we need to look at them, too. */
6147 tree target_arg_types;
6148 tree target_ret_type;
6151 unsigned int nargs, ia;
6154 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6155 target_ret_type = TREE_TYPE (target_fn_type);
6157 nargs = list_length (target_arg_types);
6158 args = XALLOCAVEC (tree, nargs);
6159 for (arg = target_arg_types, ia = 0;
6160 arg != NULL_TREE && arg != void_list_node;
6161 arg = TREE_CHAIN (arg), ++ia)
6162 args[ia] = TREE_VALUE (arg);
6165 for (fns = overload; fns; fns = OVL_NEXT (fns))
6167 tree fn = OVL_CURRENT (fns);
6171 if (TREE_CODE (fn) != TEMPLATE_DECL)
6172 /* We're only looking for templates. */
6175 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6177 /* We're not looking for a non-static member, and this is
6178 one, or vice versa. */
6181 /* Try to do argument deduction. */
6182 targs = make_tree_vec (DECL_NTPARMS (fn));
6183 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6184 target_ret_type, DEDUCE_EXACT,
6186 /* Argument deduction failed. */
6189 /* Instantiate the template. */
6190 instantiation = instantiate_template (fn, targs, flags);
6191 if (instantiation == error_mark_node)
6192 /* Instantiation failed. */
6195 /* See if there's a match. */
6196 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
6197 matches = tree_cons (instantiation, fn, matches);
6200 /* Now, remove all but the most specialized of the matches. */
6203 tree match = most_specialized_instantiation (matches);
6205 if (match != error_mark_node)
6206 matches = tree_cons (TREE_PURPOSE (match),
6212 /* Now we should have exactly one function in MATCHES. */
6213 if (matches == NULL_TREE)
6215 /* There were *no* matches. */
6216 if (flags & tf_error)
6218 error ("no matches converting function %qD to type %q#T",
6219 DECL_NAME (OVL_CURRENT (overload)),
6222 /* print_candidates expects a chain with the functions in
6223 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6224 so why be clever?). */
6225 for (; overload; overload = OVL_NEXT (overload))
6226 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
6229 print_candidates (matches);
6231 return error_mark_node;
6233 else if (TREE_CHAIN (matches))
6235 /* There were too many matches. First check if they're all
6236 the same function. */
6239 fn = TREE_PURPOSE (matches);
6240 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6241 if (!decls_match (fn, TREE_PURPOSE (match)))
6246 if (flags & tf_error)
6248 error ("converting overloaded function %qD to type %q#T is ambiguous",
6249 DECL_NAME (OVL_FUNCTION (overload)),
6252 /* Since print_candidates expects the functions in the
6253 TREE_VALUE slot, we flip them here. */
6254 for (match = matches; match; match = TREE_CHAIN (match))
6255 TREE_VALUE (match) = TREE_PURPOSE (match);
6257 print_candidates (matches);
6260 return error_mark_node;
6264 /* Good, exactly one match. Now, convert it to the correct type. */
6265 fn = TREE_PURPOSE (matches);
6267 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6268 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6270 static int explained;
6272 if (!(flags & tf_error))
6273 return error_mark_node;
6275 permerror (input_location, "assuming pointer to member %qD", fn);
6278 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6283 /* If we're doing overload resolution purely for the purpose of
6284 determining conversion sequences, we should not consider the
6285 function used. If this conversion sequence is selected, the
6286 function will be marked as used at this point. */
6287 if (!(flags & tf_conv))
6289 /* Make =delete work with SFINAE. */
6290 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6291 return error_mark_node;
6296 /* We could not check access to member functions when this
6297 expression was originally created since we did not know at that
6298 time to which function the expression referred. */
6299 if (!(flags & tf_no_access_control)
6300 && DECL_FUNCTION_MEMBER_P (fn))
6302 gcc_assert (access_path);
6303 perform_or_defer_access_check (access_path, fn, fn);
6306 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6307 return cp_build_unary_op (ADDR_EXPR, fn, 0, flags);
6310 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6311 will mark the function as addressed, but here we must do it
6313 cxx_mark_addressable (fn);
6319 /* This function will instantiate the type of the expression given in
6320 RHS to match the type of LHSTYPE. If errors exist, then return
6321 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6322 we complain on errors. If we are not complaining, never modify rhs,
6323 as overload resolution wants to try many possible instantiations, in
6324 the hope that at least one will work.
6326 For non-recursive calls, LHSTYPE should be a function, pointer to
6327 function, or a pointer to member function. */
6330 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6332 tsubst_flags_t flags_in = flags;
6333 tree access_path = NULL_TREE;
6335 flags &= ~tf_ptrmem_ok;
6337 if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
6339 if (flags & tf_error)
6340 error ("not enough type information");
6341 return error_mark_node;
6344 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6346 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6348 if (flag_ms_extensions
6349 && TYPE_PTRMEMFUNC_P (lhstype)
6350 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6351 /* Microsoft allows `A::f' to be resolved to a
6352 pointer-to-member. */
6356 if (flags & tf_error)
6357 error ("argument of type %qT does not match %qT",
6358 TREE_TYPE (rhs), lhstype);
6359 return error_mark_node;
6363 if (TREE_CODE (rhs) == BASELINK)
6365 access_path = BASELINK_ACCESS_BINFO (rhs);
6366 rhs = BASELINK_FUNCTIONS (rhs);
6369 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6370 deduce any type information. */
6371 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6373 if (flags & tf_error)
6374 error ("not enough type information");
6375 return error_mark_node;
6378 /* There only a few kinds of expressions that may have a type
6379 dependent on overload resolution. */
6380 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6381 || TREE_CODE (rhs) == COMPONENT_REF
6382 || really_overloaded_fn (rhs)
6383 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
6385 /* This should really only be used when attempting to distinguish
6386 what sort of a pointer to function we have. For now, any
6387 arithmetic operation which is not supported on pointers
6388 is rejected as an error. */
6390 switch (TREE_CODE (rhs))
6394 tree member = TREE_OPERAND (rhs, 1);
6396 member = instantiate_type (lhstype, member, flags);
6397 if (member != error_mark_node
6398 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6399 /* Do not lose object's side effects. */
6400 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6401 TREE_OPERAND (rhs, 0), member);
6406 rhs = TREE_OPERAND (rhs, 1);
6407 if (BASELINK_P (rhs))
6408 return instantiate_type (lhstype, rhs, flags_in);
6410 /* This can happen if we are forming a pointer-to-member for a
6412 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6416 case TEMPLATE_ID_EXPR:
6418 tree fns = TREE_OPERAND (rhs, 0);
6419 tree args = TREE_OPERAND (rhs, 1);
6422 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6423 /*template_only=*/true,
6430 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6431 /*template_only=*/false,
6432 /*explicit_targs=*/NULL_TREE,
6437 if (PTRMEM_OK_P (rhs))
6438 flags |= tf_ptrmem_ok;
6440 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6444 return error_mark_node;
6449 return error_mark_node;
6452 /* Return the name of the virtual function pointer field
6453 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6454 this may have to look back through base types to find the
6455 ultimate field name. (For single inheritance, these could
6456 all be the same name. Who knows for multiple inheritance). */
6459 get_vfield_name (tree type)
6461 tree binfo, base_binfo;
6464 for (binfo = TYPE_BINFO (type);
6465 BINFO_N_BASE_BINFOS (binfo);
6468 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6470 if (BINFO_VIRTUAL_P (base_binfo)
6471 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6475 type = BINFO_TYPE (binfo);
6476 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6477 + TYPE_NAME_LENGTH (type) + 2);
6478 sprintf (buf, VFIELD_NAME_FORMAT,
6479 IDENTIFIER_POINTER (constructor_name (type)));
6480 return get_identifier (buf);
6484 print_class_statistics (void)
6486 #ifdef GATHER_STATISTICS
6487 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6488 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6491 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6492 n_vtables, n_vtable_searches);
6493 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6494 n_vtable_entries, n_vtable_elems);
6499 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6500 according to [class]:
6501 The class-name is also inserted
6502 into the scope of the class itself. For purposes of access checking,
6503 the inserted class name is treated as if it were a public member name. */
6506 build_self_reference (void)
6508 tree name = constructor_name (current_class_type);
6509 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6512 DECL_NONLOCAL (value) = 1;
6513 DECL_CONTEXT (value) = current_class_type;
6514 DECL_ARTIFICIAL (value) = 1;
6515 SET_DECL_SELF_REFERENCE_P (value);
6517 if (processing_template_decl)
6518 value = push_template_decl (value);
6520 saved_cas = current_access_specifier;
6521 current_access_specifier = access_public_node;
6522 finish_member_declaration (value);
6523 current_access_specifier = saved_cas;
6526 /* Returns 1 if TYPE contains only padding bytes. */
6529 is_empty_class (tree type)
6531 if (type == error_mark_node)
6534 if (! CLASS_TYPE_P (type))
6537 /* In G++ 3.2, whether or not a class was empty was determined by
6538 looking at its size. */
6539 if (abi_version_at_least (2))
6540 return CLASSTYPE_EMPTY_P (type);
6542 return integer_zerop (CLASSTYPE_SIZE (type));
6545 /* Returns true if TYPE contains an empty class. */
6548 contains_empty_class_p (tree type)
6550 if (is_empty_class (type))
6552 if (CLASS_TYPE_P (type))
6559 for (binfo = TYPE_BINFO (type), i = 0;
6560 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6561 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6563 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6564 if (TREE_CODE (field) == FIELD_DECL
6565 && !DECL_ARTIFICIAL (field)
6566 && is_empty_class (TREE_TYPE (field)))
6569 else if (TREE_CODE (type) == ARRAY_TYPE)
6570 return contains_empty_class_p (TREE_TYPE (type));
6574 /* Returns true if TYPE contains no actual data, just various
6575 possible combinations of empty classes. */
6578 is_really_empty_class (tree type)
6580 if (is_empty_class (type))
6582 if (CLASS_TYPE_P (type))
6589 for (binfo = TYPE_BINFO (type), i = 0;
6590 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6591 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
6593 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6594 if (TREE_CODE (field) == FIELD_DECL
6595 && !DECL_ARTIFICIAL (field)
6596 && !is_really_empty_class (TREE_TYPE (field)))
6600 else if (TREE_CODE (type) == ARRAY_TYPE)
6601 return is_really_empty_class (TREE_TYPE (type));
6605 /* Note that NAME was looked up while the current class was being
6606 defined and that the result of that lookup was DECL. */
6609 maybe_note_name_used_in_class (tree name, tree decl)
6611 splay_tree names_used;
6613 /* If we're not defining a class, there's nothing to do. */
6614 if (!(innermost_scope_kind() == sk_class
6615 && TYPE_BEING_DEFINED (current_class_type)
6616 && !LAMBDA_TYPE_P (current_class_type)))
6619 /* If there's already a binding for this NAME, then we don't have
6620 anything to worry about. */
6621 if (lookup_member (current_class_type, name,
6622 /*protect=*/0, /*want_type=*/false))
6625 if (!current_class_stack[current_class_depth - 1].names_used)
6626 current_class_stack[current_class_depth - 1].names_used
6627 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6628 names_used = current_class_stack[current_class_depth - 1].names_used;
6630 splay_tree_insert (names_used,
6631 (splay_tree_key) name,
6632 (splay_tree_value) decl);
6635 /* Note that NAME was declared (as DECL) in the current class. Check
6636 to see that the declaration is valid. */
6639 note_name_declared_in_class (tree name, tree decl)
6641 splay_tree names_used;
6644 /* Look to see if we ever used this name. */
6646 = current_class_stack[current_class_depth - 1].names_used;
6650 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6653 /* [basic.scope.class]
6655 A name N used in a class S shall refer to the same declaration
6656 in its context and when re-evaluated in the completed scope of
6658 permerror (input_location, "declaration of %q#D", decl);
6659 permerror (input_location, "changes meaning of %qD from %q+#D",
6660 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6664 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6665 Secondary vtables are merged with primary vtables; this function
6666 will return the VAR_DECL for the primary vtable. */
6669 get_vtbl_decl_for_binfo (tree binfo)
6673 decl = BINFO_VTABLE (binfo);
6674 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
6676 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6677 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6680 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6685 /* Returns the binfo for the primary base of BINFO. If the resulting
6686 BINFO is a virtual base, and it is inherited elsewhere in the
6687 hierarchy, then the returned binfo might not be the primary base of
6688 BINFO in the complete object. Check BINFO_PRIMARY_P or
6689 BINFO_LOST_PRIMARY_P to be sure. */
6692 get_primary_binfo (tree binfo)
6696 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6700 return copied_binfo (primary_base, binfo);
6703 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6706 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6709 fprintf (stream, "%*s", indent, "");
6713 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6714 INDENT should be zero when called from the top level; it is
6715 incremented recursively. IGO indicates the next expected BINFO in
6716 inheritance graph ordering. */
6719 dump_class_hierarchy_r (FILE *stream,
6729 indented = maybe_indent_hierarchy (stream, indent, 0);
6730 fprintf (stream, "%s (0x%lx) ",
6731 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6732 (unsigned long) binfo);
6735 fprintf (stream, "alternative-path\n");
6738 igo = TREE_CHAIN (binfo);
6740 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6741 tree_low_cst (BINFO_OFFSET (binfo), 0));
6742 if (is_empty_class (BINFO_TYPE (binfo)))
6743 fprintf (stream, " empty");
6744 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6745 fprintf (stream, " nearly-empty");
6746 if (BINFO_VIRTUAL_P (binfo))
6747 fprintf (stream, " virtual");
6748 fprintf (stream, "\n");
6751 if (BINFO_PRIMARY_P (binfo))
6753 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6754 fprintf (stream, " primary-for %s (0x%lx)",
6755 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6756 TFF_PLAIN_IDENTIFIER),
6757 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6759 if (BINFO_LOST_PRIMARY_P (binfo))
6761 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6762 fprintf (stream, " lost-primary");
6765 fprintf (stream, "\n");
6767 if (!(flags & TDF_SLIM))
6771 if (BINFO_SUBVTT_INDEX (binfo))
6773 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6774 fprintf (stream, " subvttidx=%s",
6775 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6776 TFF_PLAIN_IDENTIFIER));
6778 if (BINFO_VPTR_INDEX (binfo))
6780 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6781 fprintf (stream, " vptridx=%s",
6782 expr_as_string (BINFO_VPTR_INDEX (binfo),
6783 TFF_PLAIN_IDENTIFIER));
6785 if (BINFO_VPTR_FIELD (binfo))
6787 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6788 fprintf (stream, " vbaseoffset=%s",
6789 expr_as_string (BINFO_VPTR_FIELD (binfo),
6790 TFF_PLAIN_IDENTIFIER));
6792 if (BINFO_VTABLE (binfo))
6794 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6795 fprintf (stream, " vptr=%s",
6796 expr_as_string (BINFO_VTABLE (binfo),
6797 TFF_PLAIN_IDENTIFIER));
6801 fprintf (stream, "\n");
6804 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6805 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6810 /* Dump the BINFO hierarchy for T. */
6813 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6815 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6816 fprintf (stream, " size=%lu align=%lu\n",
6817 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6818 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6819 fprintf (stream, " base size=%lu base align=%lu\n",
6820 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6822 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6824 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6825 fprintf (stream, "\n");
6828 /* Debug interface to hierarchy dumping. */
6831 debug_class (tree t)
6833 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6837 dump_class_hierarchy (tree t)
6840 FILE *stream = dump_begin (TDI_class, &flags);
6844 dump_class_hierarchy_1 (stream, flags, t);
6845 dump_end (TDI_class, stream);
6850 dump_array (FILE * stream, tree decl)
6853 unsigned HOST_WIDE_INT ix;
6855 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6857 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6859 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6860 fprintf (stream, " %s entries",
6861 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6862 TFF_PLAIN_IDENTIFIER));
6863 fprintf (stream, "\n");
6865 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
6867 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
6868 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
6872 dump_vtable (tree t, tree binfo, tree vtable)
6875 FILE *stream = dump_begin (TDI_class, &flags);
6880 if (!(flags & TDF_SLIM))
6882 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6884 fprintf (stream, "%s for %s",
6885 ctor_vtbl_p ? "Construction vtable" : "Vtable",
6886 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6889 if (!BINFO_VIRTUAL_P (binfo))
6890 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6891 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6893 fprintf (stream, "\n");
6894 dump_array (stream, vtable);
6895 fprintf (stream, "\n");
6898 dump_end (TDI_class, stream);
6902 dump_vtt (tree t, tree vtt)
6905 FILE *stream = dump_begin (TDI_class, &flags);
6910 if (!(flags & TDF_SLIM))
6912 fprintf (stream, "VTT for %s\n",
6913 type_as_string (t, TFF_PLAIN_IDENTIFIER));
6914 dump_array (stream, vtt);
6915 fprintf (stream, "\n");
6918 dump_end (TDI_class, stream);
6921 /* Dump a function or thunk and its thunkees. */
6924 dump_thunk (FILE *stream, int indent, tree thunk)
6926 static const char spaces[] = " ";
6927 tree name = DECL_NAME (thunk);
6930 fprintf (stream, "%.*s%p %s %s", indent, spaces,
6932 !DECL_THUNK_P (thunk) ? "function"
6933 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6934 name ? IDENTIFIER_POINTER (name) : "<unset>");
6935 if (DECL_THUNK_P (thunk))
6937 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6938 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6940 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6941 if (!virtual_adjust)
6943 else if (DECL_THIS_THUNK_P (thunk))
6944 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
6945 tree_low_cst (virtual_adjust, 0));
6947 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6948 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6949 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6950 if (THUNK_ALIAS (thunk))
6951 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6953 fprintf (stream, "\n");
6954 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6955 dump_thunk (stream, indent + 2, thunks);
6958 /* Dump the thunks for FN. */
6961 debug_thunks (tree fn)
6963 dump_thunk (stderr, 0, fn);
6966 /* Virtual function table initialization. */
6968 /* Create all the necessary vtables for T and its base classes. */
6971 finish_vtbls (tree t)
6976 /* We lay out the primary and secondary vtables in one contiguous
6977 vtable. The primary vtable is first, followed by the non-virtual
6978 secondary vtables in inheritance graph order. */
6979 list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6980 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6981 TYPE_BINFO (t), t, list);
6983 /* Then come the virtual bases, also in inheritance graph order. */
6984 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6986 if (!BINFO_VIRTUAL_P (vbase))
6988 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6991 if (BINFO_VTABLE (TYPE_BINFO (t)))
6992 initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
6995 /* Initialize the vtable for BINFO with the INITS. */
6998 initialize_vtable (tree binfo, tree inits)
7002 layout_vtable_decl (binfo, list_length (inits));
7003 decl = get_vtbl_decl_for_binfo (binfo);
7004 initialize_artificial_var (decl, inits);
7005 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
7008 /* Build the VTT (virtual table table) for T.
7009 A class requires a VTT if it has virtual bases.
7012 1 - primary virtual pointer for complete object T
7013 2 - secondary VTTs for each direct non-virtual base of T which requires a
7015 3 - secondary virtual pointers for each direct or indirect base of T which
7016 has virtual bases or is reachable via a virtual path from T.
7017 4 - secondary VTTs for each direct or indirect virtual base of T.
7019 Secondary VTTs look like complete object VTTs without part 4. */
7029 /* Build up the initializers for the VTT. */
7031 index = size_zero_node;
7032 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7034 /* If we didn't need a VTT, we're done. */
7038 /* Figure out the type of the VTT. */
7039 type = build_index_type (size_int (list_length (inits) - 1));
7040 type = build_cplus_array_type (const_ptr_type_node, type);
7042 /* Now, build the VTT object itself. */
7043 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7044 initialize_artificial_var (vtt, inits);
7045 /* Add the VTT to the vtables list. */
7046 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
7047 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7052 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7053 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7054 and CHAIN the vtable pointer for this binfo after construction is
7055 complete. VALUE can also be another BINFO, in which case we recurse. */
7058 binfo_ctor_vtable (tree binfo)
7064 vt = BINFO_VTABLE (binfo);
7065 if (TREE_CODE (vt) == TREE_LIST)
7066 vt = TREE_VALUE (vt);
7067 if (TREE_CODE (vt) == TREE_BINFO)
7076 /* Data for secondary VTT initialization. */
7077 typedef struct secondary_vptr_vtt_init_data_s
7079 /* Is this the primary VTT? */
7082 /* Current index into the VTT. */
7085 /* TREE_LIST of initializers built up. */
7088 /* The type being constructed by this secondary VTT. */
7089 tree type_being_constructed;
7090 } secondary_vptr_vtt_init_data;
7092 /* Recursively build the VTT-initializer for BINFO (which is in the
7093 hierarchy dominated by T). INITS points to the end of the initializer
7094 list to date. INDEX is the VTT index where the next element will be
7095 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7096 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7097 for virtual bases of T. When it is not so, we build the constructor
7098 vtables for the BINFO-in-T variant. */
7101 build_vtt_inits (tree binfo, tree t, tree *inits, tree *index)
7106 tree secondary_vptrs;
7107 secondary_vptr_vtt_init_data data;
7108 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7110 /* We only need VTTs for subobjects with virtual bases. */
7111 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7114 /* We need to use a construction vtable if this is not the primary
7118 build_ctor_vtbl_group (binfo, t);
7120 /* Record the offset in the VTT where this sub-VTT can be found. */
7121 BINFO_SUBVTT_INDEX (binfo) = *index;
7124 /* Add the address of the primary vtable for the complete object. */
7125 init = binfo_ctor_vtable (binfo);
7126 *inits = build_tree_list (NULL_TREE, init);
7127 inits = &TREE_CHAIN (*inits);
7130 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7131 BINFO_VPTR_INDEX (binfo) = *index;
7133 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7135 /* Recursively add the secondary VTTs for non-virtual bases. */
7136 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7137 if (!BINFO_VIRTUAL_P (b))
7138 inits = build_vtt_inits (b, t, inits, index);
7140 /* Add secondary virtual pointers for all subobjects of BINFO with
7141 either virtual bases or reachable along a virtual path, except
7142 subobjects that are non-virtual primary bases. */
7143 data.top_level_p = top_level_p;
7144 data.index = *index;
7146 data.type_being_constructed = BINFO_TYPE (binfo);
7148 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7150 *index = data.index;
7152 /* The secondary vptrs come back in reverse order. After we reverse
7153 them, and add the INITS, the last init will be the first element
7155 secondary_vptrs = data.inits;
7156 if (secondary_vptrs)
7158 *inits = nreverse (secondary_vptrs);
7159 inits = &TREE_CHAIN (secondary_vptrs);
7160 gcc_assert (*inits == NULL_TREE);
7164 /* Add the secondary VTTs for virtual bases in inheritance graph
7166 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7168 if (!BINFO_VIRTUAL_P (b))
7171 inits = build_vtt_inits (b, t, inits, index);
7174 /* Remove the ctor vtables we created. */
7175 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7180 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7181 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7184 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7186 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7188 /* We don't care about bases that don't have vtables. */
7189 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7190 return dfs_skip_bases;
7192 /* We're only interested in proper subobjects of the type being
7194 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7197 /* We're only interested in bases with virtual bases or reachable
7198 via a virtual path from the type being constructed. */
7199 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7200 || binfo_via_virtual (binfo, data->type_being_constructed)))
7201 return dfs_skip_bases;
7203 /* We're not interested in non-virtual primary bases. */
7204 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7207 /* Record the index where this secondary vptr can be found. */
7208 if (data->top_level_p)
7210 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7211 BINFO_VPTR_INDEX (binfo) = data->index;
7213 if (BINFO_VIRTUAL_P (binfo))
7215 /* It's a primary virtual base, and this is not a
7216 construction vtable. Find the base this is primary of in
7217 the inheritance graph, and use that base's vtable
7219 while (BINFO_PRIMARY_P (binfo))
7220 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7224 /* Add the initializer for the secondary vptr itself. */
7225 data->inits = tree_cons (NULL_TREE, binfo_ctor_vtable (binfo), data->inits);
7227 /* Advance the vtt index. */
7228 data->index = size_binop (PLUS_EXPR, data->index,
7229 TYPE_SIZE_UNIT (ptr_type_node));
7234 /* Called from build_vtt_inits via dfs_walk. After building
7235 constructor vtables and generating the sub-vtt from them, we need
7236 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7237 binfo of the base whose sub vtt was generated. */
7240 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7242 tree vtable = BINFO_VTABLE (binfo);
7244 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7245 /* If this class has no vtable, none of its bases do. */
7246 return dfs_skip_bases;
7249 /* This might be a primary base, so have no vtable in this
7253 /* If we scribbled the construction vtable vptr into BINFO, clear it
7255 if (TREE_CODE (vtable) == TREE_LIST
7256 && (TREE_PURPOSE (vtable) == (tree) data))
7257 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7262 /* Build the construction vtable group for BINFO which is in the
7263 hierarchy dominated by T. */
7266 build_ctor_vtbl_group (tree binfo, tree t)
7275 /* See if we've already created this construction vtable group. */
7276 id = mangle_ctor_vtbl_for_type (t, binfo);
7277 if (IDENTIFIER_GLOBAL_VALUE (id))
7280 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7281 /* Build a version of VTBL (with the wrong type) for use in
7282 constructing the addresses of secondary vtables in the
7283 construction vtable group. */
7284 vtbl = build_vtable (t, id, ptr_type_node);
7285 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7286 list = build_tree_list (vtbl, NULL_TREE);
7287 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7290 /* Add the vtables for each of our virtual bases using the vbase in T
7292 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7294 vbase = TREE_CHAIN (vbase))
7298 if (!BINFO_VIRTUAL_P (vbase))
7300 b = copied_binfo (vbase, binfo);
7302 accumulate_vtbl_inits (b, vbase, binfo, t, list);
7304 inits = TREE_VALUE (list);
7306 /* Figure out the type of the construction vtable. */
7307 type = build_index_type (size_int (list_length (inits) - 1));
7308 type = build_cplus_array_type (vtable_entry_type, type);
7310 TREE_TYPE (vtbl) = type;
7311 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7312 layout_decl (vtbl, 0);
7314 /* Initialize the construction vtable. */
7315 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7316 initialize_artificial_var (vtbl, inits);
7317 dump_vtable (t, binfo, vtbl);
7320 /* Add the vtbl initializers for BINFO (and its bases other than
7321 non-virtual primaries) to the list of INITS. BINFO is in the
7322 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7323 the constructor the vtbl inits should be accumulated for. (If this
7324 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7325 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7326 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7327 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7328 but are not necessarily the same in terms of layout. */
7331 accumulate_vtbl_inits (tree binfo,
7339 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7341 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7343 /* If it doesn't have a vptr, we don't do anything. */
7344 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7347 /* If we're building a construction vtable, we're not interested in
7348 subobjects that don't require construction vtables. */
7350 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7351 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7354 /* Build the initializers for the BINFO-in-T vtable. */
7356 = chainon (TREE_VALUE (inits),
7357 dfs_accumulate_vtbl_inits (binfo, orig_binfo,
7358 rtti_binfo, t, inits));
7360 /* Walk the BINFO and its bases. We walk in preorder so that as we
7361 initialize each vtable we can figure out at what offset the
7362 secondary vtable lies from the primary vtable. We can't use
7363 dfs_walk here because we need to iterate through bases of BINFO
7364 and RTTI_BINFO simultaneously. */
7365 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7367 /* Skip virtual bases. */
7368 if (BINFO_VIRTUAL_P (base_binfo))
7370 accumulate_vtbl_inits (base_binfo,
7371 BINFO_BASE_BINFO (orig_binfo, i),
7377 /* Called from accumulate_vtbl_inits. Returns the initializers for
7378 the BINFO vtable. */
7381 dfs_accumulate_vtbl_inits (tree binfo,
7387 tree inits = NULL_TREE;
7388 tree vtbl = NULL_TREE;
7389 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7392 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7394 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7395 primary virtual base. If it is not the same primary in
7396 the hierarchy of T, we'll need to generate a ctor vtable
7397 for it, to place at its location in T. If it is the same
7398 primary, we still need a VTT entry for the vtable, but it
7399 should point to the ctor vtable for the base it is a
7400 primary for within the sub-hierarchy of RTTI_BINFO.
7402 There are three possible cases:
7404 1) We are in the same place.
7405 2) We are a primary base within a lost primary virtual base of
7407 3) We are primary to something not a base of RTTI_BINFO. */
7410 tree last = NULL_TREE;
7412 /* First, look through the bases we are primary to for RTTI_BINFO
7413 or a virtual base. */
7415 while (BINFO_PRIMARY_P (b))
7417 b = BINFO_INHERITANCE_CHAIN (b);
7419 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7422 /* If we run out of primary links, keep looking down our
7423 inheritance chain; we might be an indirect primary. */
7424 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7425 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7429 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7430 base B and it is a base of RTTI_BINFO, this is case 2. In
7431 either case, we share our vtable with LAST, i.e. the
7432 derived-most base within B of which we are a primary. */
7434 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7435 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7436 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7437 binfo_ctor_vtable after everything's been set up. */
7440 /* Otherwise, this is case 3 and we get our own. */
7442 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7450 /* Compute the initializer for this vtable. */
7451 inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7454 /* Figure out the position to which the VPTR should point. */
7455 vtbl = TREE_PURPOSE (l);
7456 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7457 index = size_binop (PLUS_EXPR,
7458 size_int (non_fn_entries),
7459 size_int (list_length (TREE_VALUE (l))));
7460 index = size_binop (MULT_EXPR,
7461 TYPE_SIZE_UNIT (vtable_entry_type),
7463 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7467 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7468 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7469 straighten this out. */
7470 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7471 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7474 /* For an ordinary vtable, set BINFO_VTABLE. */
7475 BINFO_VTABLE (binfo) = vtbl;
7480 static GTY(()) tree abort_fndecl_addr;
7482 /* Construct the initializer for BINFO's virtual function table. BINFO
7483 is part of the hierarchy dominated by T. If we're building a
7484 construction vtable, the ORIG_BINFO is the binfo we should use to
7485 find the actual function pointers to put in the vtable - but they
7486 can be overridden on the path to most-derived in the graph that
7487 ORIG_BINFO belongs. Otherwise,
7488 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7489 BINFO that should be indicated by the RTTI information in the
7490 vtable; it will be a base class of T, rather than T itself, if we
7491 are building a construction vtable.
7493 The value returned is a TREE_LIST suitable for wrapping in a
7494 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7495 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7496 number of non-function entries in the vtable.
7498 It might seem that this function should never be called with a
7499 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7500 base is always subsumed by a derived class vtable. However, when
7501 we are building construction vtables, we do build vtables for
7502 primary bases; we need these while the primary base is being
7506 build_vtbl_initializer (tree binfo,
7510 int* non_fn_entries_p)
7517 VEC(tree,gc) *vbases;
7519 /* Initialize VID. */
7520 memset (&vid, 0, sizeof (vid));
7523 vid.rtti_binfo = rtti_binfo;
7524 vid.last_init = &vid.inits;
7525 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7526 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7527 vid.generate_vcall_entries = true;
7528 /* The first vbase or vcall offset is at index -3 in the vtable. */
7529 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7531 /* Add entries to the vtable for RTTI. */
7532 build_rtti_vtbl_entries (binfo, &vid);
7534 /* Create an array for keeping track of the functions we've
7535 processed. When we see multiple functions with the same
7536 signature, we share the vcall offsets. */
7537 vid.fns = VEC_alloc (tree, gc, 32);
7538 /* Add the vcall and vbase offset entries. */
7539 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7541 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7542 build_vbase_offset_vtbl_entries. */
7543 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7544 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7545 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7547 /* If the target requires padding between data entries, add that now. */
7548 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7552 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7557 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7558 add = tree_cons (NULL_TREE,
7559 build1 (NOP_EXPR, vtable_entry_type,
7566 if (non_fn_entries_p)
7567 *non_fn_entries_p = list_length (vid.inits);
7569 /* Go through all the ordinary virtual functions, building up
7571 vfun_inits = NULL_TREE;
7572 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7576 tree fn, fn_original;
7577 tree init = NULL_TREE;
7581 if (DECL_THUNK_P (fn))
7583 if (!DECL_NAME (fn))
7585 if (THUNK_ALIAS (fn))
7587 fn = THUNK_ALIAS (fn);
7590 fn_original = THUNK_TARGET (fn);
7593 /* If the only definition of this function signature along our
7594 primary base chain is from a lost primary, this vtable slot will
7595 never be used, so just zero it out. This is important to avoid
7596 requiring extra thunks which cannot be generated with the function.
7598 We first check this in update_vtable_entry_for_fn, so we handle
7599 restored primary bases properly; we also need to do it here so we
7600 zero out unused slots in ctor vtables, rather than filling them
7601 with erroneous values (though harmless, apart from relocation
7603 for (b = binfo; ; b = get_primary_binfo (b))
7605 /* We found a defn before a lost primary; go ahead as normal. */
7606 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7609 /* The nearest definition is from a lost primary; clear the
7611 if (BINFO_LOST_PRIMARY_P (b))
7613 init = size_zero_node;
7620 /* Pull the offset for `this', and the function to call, out of
7622 delta = BV_DELTA (v);
7623 vcall_index = BV_VCALL_INDEX (v);
7625 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7626 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7628 /* You can't call an abstract virtual function; it's abstract.
7629 So, we replace these functions with __pure_virtual. */
7630 if (DECL_PURE_VIRTUAL_P (fn_original))
7633 if (abort_fndecl_addr == NULL)
7634 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7635 init = abort_fndecl_addr;
7639 if (!integer_zerop (delta) || vcall_index)
7641 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7642 if (!DECL_NAME (fn))
7645 /* Take the address of the function, considering it to be of an
7646 appropriate generic type. */
7647 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7651 /* And add it to the chain of initializers. */
7652 if (TARGET_VTABLE_USES_DESCRIPTORS)
7655 if (init == size_zero_node)
7656 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7657 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7659 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7661 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7662 TREE_OPERAND (init, 0),
7663 build_int_cst (NULL_TREE, i));
7664 TREE_CONSTANT (fdesc) = 1;
7666 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7670 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7673 /* The initializers for virtual functions were built up in reverse
7674 order; straighten them out now. */
7675 vfun_inits = nreverse (vfun_inits);
7677 /* The negative offset initializers are also in reverse order. */
7678 vid.inits = nreverse (vid.inits);
7680 /* Chain the two together. */
7681 return chainon (vid.inits, vfun_inits);
7684 /* Adds to vid->inits the initializers for the vbase and vcall
7685 offsets in BINFO, which is in the hierarchy dominated by T. */
7688 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7692 /* If this is a derived class, we must first create entries
7693 corresponding to the primary base class. */
7694 b = get_primary_binfo (binfo);
7696 build_vcall_and_vbase_vtbl_entries (b, vid);
7698 /* Add the vbase entries for this base. */
7699 build_vbase_offset_vtbl_entries (binfo, vid);
7700 /* Add the vcall entries for this base. */
7701 build_vcall_offset_vtbl_entries (binfo, vid);
7704 /* Returns the initializers for the vbase offset entries in the vtable
7705 for BINFO (which is part of the class hierarchy dominated by T), in
7706 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7707 where the next vbase offset will go. */
7710 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7714 tree non_primary_binfo;
7716 /* If there are no virtual baseclasses, then there is nothing to
7718 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7723 /* We might be a primary base class. Go up the inheritance hierarchy
7724 until we find the most derived class of which we are a primary base:
7725 it is the offset of that which we need to use. */
7726 non_primary_binfo = binfo;
7727 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7731 /* If we have reached a virtual base, then it must be a primary
7732 base (possibly multi-level) of vid->binfo, or we wouldn't
7733 have called build_vcall_and_vbase_vtbl_entries for it. But it
7734 might be a lost primary, so just skip down to vid->binfo. */
7735 if (BINFO_VIRTUAL_P (non_primary_binfo))
7737 non_primary_binfo = vid->binfo;
7741 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7742 if (get_primary_binfo (b) != non_primary_binfo)
7744 non_primary_binfo = b;
7747 /* Go through the virtual bases, adding the offsets. */
7748 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7750 vbase = TREE_CHAIN (vbase))
7755 if (!BINFO_VIRTUAL_P (vbase))
7758 /* Find the instance of this virtual base in the complete
7760 b = copied_binfo (vbase, binfo);
7762 /* If we've already got an offset for this virtual base, we
7763 don't need another one. */
7764 if (BINFO_VTABLE_PATH_MARKED (b))
7766 BINFO_VTABLE_PATH_MARKED (b) = 1;
7768 /* Figure out where we can find this vbase offset. */
7769 delta = size_binop (MULT_EXPR,
7772 TYPE_SIZE_UNIT (vtable_entry_type)));
7773 if (vid->primary_vtbl_p)
7774 BINFO_VPTR_FIELD (b) = delta;
7776 if (binfo != TYPE_BINFO (t))
7777 /* The vbase offset had better be the same. */
7778 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7780 /* The next vbase will come at a more negative offset. */
7781 vid->index = size_binop (MINUS_EXPR, vid->index,
7782 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7784 /* The initializer is the delta from BINFO to this virtual base.
7785 The vbase offsets go in reverse inheritance-graph order, and
7786 we are walking in inheritance graph order so these end up in
7788 delta = size_diffop_loc (input_location,
7789 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7792 = build_tree_list (NULL_TREE,
7793 fold_build1_loc (input_location, NOP_EXPR,
7796 vid->last_init = &TREE_CHAIN (*vid->last_init);
7800 /* Adds the initializers for the vcall offset entries in the vtable
7801 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7805 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7807 /* We only need these entries if this base is a virtual base. We
7808 compute the indices -- but do not add to the vtable -- when
7809 building the main vtable for a class. */
7810 if (binfo == TYPE_BINFO (vid->derived)
7811 || (BINFO_VIRTUAL_P (binfo)
7812 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7813 correspond to VID->DERIVED), we are building a primary
7814 construction virtual table. Since this is a primary
7815 virtual table, we do not need the vcall offsets for
7817 && binfo != vid->rtti_binfo))
7819 /* We need a vcall offset for each of the virtual functions in this
7820 vtable. For example:
7822 class A { virtual void f (); };
7823 class B1 : virtual public A { virtual void f (); };
7824 class B2 : virtual public A { virtual void f (); };
7825 class C: public B1, public B2 { virtual void f (); };
7827 A C object has a primary base of B1, which has a primary base of A. A
7828 C also has a secondary base of B2, which no longer has a primary base
7829 of A. So the B2-in-C construction vtable needs a secondary vtable for
7830 A, which will adjust the A* to a B2* to call f. We have no way of
7831 knowing what (or even whether) this offset will be when we define B2,
7832 so we store this "vcall offset" in the A sub-vtable and look it up in
7833 a "virtual thunk" for B2::f.
7835 We need entries for all the functions in our primary vtable and
7836 in our non-virtual bases' secondary vtables. */
7838 /* If we are just computing the vcall indices -- but do not need
7839 the actual entries -- not that. */
7840 if (!BINFO_VIRTUAL_P (binfo))
7841 vid->generate_vcall_entries = false;
7842 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7843 add_vcall_offset_vtbl_entries_r (binfo, vid);
7847 /* Build vcall offsets, starting with those for BINFO. */
7850 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7856 /* Don't walk into virtual bases -- except, of course, for the
7857 virtual base for which we are building vcall offsets. Any
7858 primary virtual base will have already had its offsets generated
7859 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7860 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7863 /* If BINFO has a primary base, process it first. */
7864 primary_binfo = get_primary_binfo (binfo);
7866 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7868 /* Add BINFO itself to the list. */
7869 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7871 /* Scan the non-primary bases of BINFO. */
7872 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7873 if (base_binfo != primary_binfo)
7874 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7877 /* Called from build_vcall_offset_vtbl_entries_r. */
7880 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7882 /* Make entries for the rest of the virtuals. */
7883 if (abi_version_at_least (2))
7887 /* The ABI requires that the methods be processed in declaration
7888 order. G++ 3.2 used the order in the vtable. */
7889 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7891 orig_fn = TREE_CHAIN (orig_fn))
7892 if (DECL_VINDEX (orig_fn))
7893 add_vcall_offset (orig_fn, binfo, vid);
7897 tree derived_virtuals;
7900 /* If BINFO is a primary base, the most derived class which has
7901 BINFO as a primary base; otherwise, just BINFO. */
7902 tree non_primary_binfo;
7904 /* We might be a primary base class. Go up the inheritance hierarchy
7905 until we find the most derived class of which we are a primary base:
7906 it is the BINFO_VIRTUALS there that we need to consider. */
7907 non_primary_binfo = binfo;
7908 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7912 /* If we have reached a virtual base, then it must be vid->vbase,
7913 because we ignore other virtual bases in
7914 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7915 base (possibly multi-level) of vid->binfo, or we wouldn't
7916 have called build_vcall_and_vbase_vtbl_entries for it. But it
7917 might be a lost primary, so just skip down to vid->binfo. */
7918 if (BINFO_VIRTUAL_P (non_primary_binfo))
7920 gcc_assert (non_primary_binfo == vid->vbase);
7921 non_primary_binfo = vid->binfo;
7925 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7926 if (get_primary_binfo (b) != non_primary_binfo)
7928 non_primary_binfo = b;
7931 if (vid->ctor_vtbl_p)
7932 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7933 where rtti_binfo is the most derived type. */
7935 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7937 for (base_virtuals = BINFO_VIRTUALS (binfo),
7938 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7939 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7941 base_virtuals = TREE_CHAIN (base_virtuals),
7942 derived_virtuals = TREE_CHAIN (derived_virtuals),
7943 orig_virtuals = TREE_CHAIN (orig_virtuals))
7947 /* Find the declaration that originally caused this function to
7948 be present in BINFO_TYPE (binfo). */
7949 orig_fn = BV_FN (orig_virtuals);
7951 /* When processing BINFO, we only want to generate vcall slots for
7952 function slots introduced in BINFO. So don't try to generate
7953 one if the function isn't even defined in BINFO. */
7954 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7957 add_vcall_offset (orig_fn, binfo, vid);
7962 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7965 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7971 /* If there is already an entry for a function with the same
7972 signature as FN, then we do not need a second vcall offset.
7973 Check the list of functions already present in the derived
7975 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7977 if (same_signature_p (derived_entry, orig_fn)
7978 /* We only use one vcall offset for virtual destructors,
7979 even though there are two virtual table entries. */
7980 || (DECL_DESTRUCTOR_P (derived_entry)
7981 && DECL_DESTRUCTOR_P (orig_fn)))
7985 /* If we are building these vcall offsets as part of building
7986 the vtable for the most derived class, remember the vcall
7988 if (vid->binfo == TYPE_BINFO (vid->derived))
7990 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
7991 CLASSTYPE_VCALL_INDICES (vid->derived),
7993 elt->purpose = orig_fn;
7994 elt->value = vid->index;
7997 /* The next vcall offset will be found at a more negative
7999 vid->index = size_binop (MINUS_EXPR, vid->index,
8000 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8002 /* Keep track of this function. */
8003 VEC_safe_push (tree, gc, vid->fns, orig_fn);
8005 if (vid->generate_vcall_entries)
8010 /* Find the overriding function. */
8011 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8012 if (fn == error_mark_node)
8013 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
8017 base = TREE_VALUE (fn);
8019 /* The vbase we're working on is a primary base of
8020 vid->binfo. But it might be a lost primary, so its
8021 BINFO_OFFSET might be wrong, so we just use the
8022 BINFO_OFFSET from vid->binfo. */
8023 vcall_offset = size_diffop_loc (input_location,
8024 BINFO_OFFSET (base),
8025 BINFO_OFFSET (vid->binfo));
8026 vcall_offset = fold_build1_loc (input_location,
8027 NOP_EXPR, vtable_entry_type,
8030 /* Add the initializer to the vtable. */
8031 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
8032 vid->last_init = &TREE_CHAIN (*vid->last_init);
8036 /* Return vtbl initializers for the RTTI entries corresponding to the
8037 BINFO's vtable. The RTTI entries should indicate the object given
8038 by VID->rtti_binfo. */
8041 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8050 basetype = BINFO_TYPE (binfo);
8051 t = BINFO_TYPE (vid->rtti_binfo);
8053 /* To find the complete object, we will first convert to our most
8054 primary base, and then add the offset in the vtbl to that value. */
8056 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8057 && !BINFO_LOST_PRIMARY_P (b))
8061 primary_base = get_primary_binfo (b);
8062 gcc_assert (BINFO_PRIMARY_P (primary_base)
8063 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8066 offset = size_diffop_loc (input_location,
8067 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8069 /* The second entry is the address of the typeinfo object. */
8071 decl = build_address (get_tinfo_decl (t));
8073 decl = integer_zero_node;
8075 /* Convert the declaration to a type that can be stored in the
8077 init = build_nop (vfunc_ptr_type_node, decl);
8078 *vid->last_init = build_tree_list (NULL_TREE, init);
8079 vid->last_init = &TREE_CHAIN (*vid->last_init);
8081 /* Add the offset-to-top entry. It comes earlier in the vtable than
8082 the typeinfo entry. Convert the offset to look like a
8083 function pointer, so that we can put it in the vtable. */
8084 init = build_nop (vfunc_ptr_type_node, offset);
8085 *vid->last_init = build_tree_list (NULL_TREE, init);
8086 vid->last_init = &TREE_CHAIN (*vid->last_init);
8089 /* Fold a OBJ_TYPE_REF expression to the address of a function.
8090 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
8093 cp_fold_obj_type_ref (tree ref, tree known_type)
8095 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
8096 HOST_WIDE_INT i = 0;
8097 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
8102 i += (TARGET_VTABLE_USES_DESCRIPTORS
8103 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
8109 #ifdef ENABLE_CHECKING
8110 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
8111 DECL_VINDEX (fndecl)));
8114 cgraph_node (fndecl)->local.vtable_method = true;
8116 return build_address (fndecl);
8119 #include "gt-cp-class.h"