1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
38 #include "tree-dump.h"
39 #include "splay-tree.h"
40 #include "pointer-set.h"
42 /* The number of nested classes being processed. If we are not in the
43 scope of any class, this is zero. */
45 int current_class_depth;
47 /* In order to deal with nested classes, we keep a stack of classes.
48 The topmost entry is the innermost class, and is the entry at index
49 CURRENT_CLASS_DEPTH */
51 typedef struct class_stack_node {
52 /* The name of the class. */
55 /* The _TYPE node for the class. */
58 /* The access specifier pending for new declarations in the scope of
62 /* If were defining TYPE, the names used in this class. */
63 splay_tree names_used;
65 /* Nonzero if this class is no longer open, because of a call to
68 }* class_stack_node_t;
70 typedef struct vtbl_init_data_s
72 /* The base for which we're building initializers. */
74 /* The type of the most-derived type. */
76 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
77 unless ctor_vtbl_p is true. */
79 /* The negative-index vtable initializers built up so far. These
80 are in order from least negative index to most negative index. */
81 VEC(constructor_elt,gc) *inits;
82 /* The binfo for the virtual base for which we're building
83 vcall offset initializers. */
85 /* The functions in vbase for which we have already provided vcall
88 /* The vtable index of the next vcall or vbase offset. */
90 /* Nonzero if we are building the initializer for the primary
93 /* Nonzero if we are building the initializer for a construction
96 /* True when adding vcall offset entries to the vtable. False when
97 merely computing the indices. */
98 bool generate_vcall_entries;
101 /* The type of a function passed to walk_subobject_offsets. */
102 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
104 /* The stack itself. This is a dynamically resized array. The
105 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
106 static int current_class_stack_size;
107 static class_stack_node_t current_class_stack;
109 /* The size of the largest empty class seen in this translation unit. */
110 static GTY (()) tree sizeof_biggest_empty_class;
112 /* An array of all local classes present in this translation unit, in
113 declaration order. */
114 VEC(tree,gc) *local_classes;
116 static tree get_vfield_name (tree);
117 static void finish_struct_anon (tree);
118 static tree get_vtable_name (tree);
119 static tree get_basefndecls (tree, tree);
120 static int build_primary_vtable (tree, tree);
121 static int build_secondary_vtable (tree);
122 static void finish_vtbls (tree);
123 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
124 static void finish_struct_bits (tree);
125 static int alter_access (tree, tree, tree);
126 static void handle_using_decl (tree, tree);
127 static tree dfs_modify_vtables (tree, void *);
128 static tree modify_all_vtables (tree, tree);
129 static void determine_primary_bases (tree);
130 static void finish_struct_methods (tree);
131 static void maybe_warn_about_overly_private_class (tree);
132 static int method_name_cmp (const void *, const void *);
133 static int resort_method_name_cmp (const void *, const void *);
134 static void add_implicitly_declared_members (tree, int, int);
135 static tree fixed_type_or_null (tree, int *, int *);
136 static tree build_simple_base_path (tree expr, tree binfo);
137 static tree build_vtbl_ref_1 (tree, tree);
138 static void build_vtbl_initializer (tree, tree, tree, tree, int *,
139 VEC(constructor_elt,gc) **);
140 static int count_fields (tree);
141 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
142 static bool check_bitfield_decl (tree);
143 static void check_field_decl (tree, tree, int *, int *, int *);
144 static void check_field_decls (tree, tree *, int *, int *);
145 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
146 static void build_base_fields (record_layout_info, splay_tree, tree *);
147 static void check_methods (tree);
148 static void remove_zero_width_bit_fields (tree);
149 static void check_bases (tree, int *, int *);
150 static void check_bases_and_members (tree);
151 static tree create_vtable_ptr (tree, tree *);
152 static void include_empty_classes (record_layout_info);
153 static void layout_class_type (tree, tree *);
154 static void propagate_binfo_offsets (tree, tree);
155 static void layout_virtual_bases (record_layout_info, splay_tree);
156 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
157 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
158 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
159 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
160 static void add_vcall_offset (tree, tree, vtbl_init_data *);
161 static void layout_vtable_decl (tree, int);
162 static tree dfs_find_final_overrider_pre (tree, void *);
163 static tree dfs_find_final_overrider_post (tree, void *);
164 static tree find_final_overrider (tree, tree, tree);
165 static int make_new_vtable (tree, tree);
166 static tree get_primary_binfo (tree);
167 static int maybe_indent_hierarchy (FILE *, int, int);
168 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
169 static void dump_class_hierarchy (tree);
170 static void dump_class_hierarchy_1 (FILE *, int, tree);
171 static void dump_array (FILE *, tree);
172 static void dump_vtable (tree, tree, tree);
173 static void dump_vtt (tree, tree);
174 static void dump_thunk (FILE *, int, tree);
175 static tree build_vtable (tree, tree, tree);
176 static void initialize_vtable (tree, VEC(constructor_elt,gc) *);
177 static void layout_nonempty_base_or_field (record_layout_info,
178 tree, tree, splay_tree);
179 static tree end_of_class (tree, int);
180 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
181 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree,
182 VEC(constructor_elt,gc) **);
183 static void dfs_accumulate_vtbl_inits (tree, tree, tree, tree, tree,
184 VEC(constructor_elt,gc) **);
185 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
186 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
187 static void clone_constructors_and_destructors (tree);
188 static tree build_clone (tree, tree);
189 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
190 static void build_ctor_vtbl_group (tree, tree);
191 static void build_vtt (tree);
192 static tree binfo_ctor_vtable (tree);
193 static void build_vtt_inits (tree, tree, VEC(constructor_elt,gc) **, tree *);
194 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
195 static tree dfs_fixup_binfo_vtbls (tree, void *);
196 static int record_subobject_offset (tree, tree, splay_tree);
197 static int check_subobject_offset (tree, tree, splay_tree);
198 static int walk_subobject_offsets (tree, subobject_offset_fn,
199 tree, splay_tree, tree, int);
200 static void record_subobject_offsets (tree, tree, splay_tree, bool);
201 static int layout_conflict_p (tree, tree, splay_tree, int);
202 static int splay_tree_compare_integer_csts (splay_tree_key k1,
204 static void warn_about_ambiguous_bases (tree);
205 static bool type_requires_array_cookie (tree);
206 static bool contains_empty_class_p (tree);
207 static bool base_derived_from (tree, tree);
208 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
209 static tree end_of_base (tree);
210 static tree get_vcall_index (tree, tree);
212 /* Variables shared between class.c and call.c. */
214 #ifdef GATHER_STATISTICS
216 int n_vtable_entries = 0;
217 int n_vtable_searches = 0;
218 int n_vtable_elems = 0;
219 int n_convert_harshness = 0;
220 int n_compute_conversion_costs = 0;
221 int n_inner_fields_searched = 0;
224 /* Convert to or from a base subobject. EXPR is an expression of type
225 `A' or `A*', an expression of type `B' or `B*' is returned. To
226 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
227 the B base instance within A. To convert base A to derived B, CODE
228 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
229 In this latter case, A must not be a morally virtual base of B.
230 NONNULL is true if EXPR is known to be non-NULL (this is only
231 needed when EXPR is of pointer type). CV qualifiers are preserved
235 build_base_path (enum tree_code code,
240 tree v_binfo = NULL_TREE;
241 tree d_binfo = NULL_TREE;
245 tree null_test = NULL;
246 tree ptr_target_type;
248 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
249 bool has_empty = false;
252 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
253 return error_mark_node;
255 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
258 if (is_empty_class (BINFO_TYPE (probe)))
260 if (!v_binfo && BINFO_VIRTUAL_P (probe))
264 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
266 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
268 gcc_assert ((code == MINUS_EXPR
269 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
270 || (code == PLUS_EXPR
271 && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
273 if (binfo == d_binfo)
277 if (code == MINUS_EXPR && v_binfo)
279 error ("cannot convert from base %qT to derived type %qT via virtual base %qT",
280 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
281 return error_mark_node;
285 /* This must happen before the call to save_expr. */
286 expr = cp_build_addr_expr (expr, tf_warning_or_error);
288 expr = mark_rvalue_use (expr);
290 offset = BINFO_OFFSET (binfo);
291 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
292 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
293 /* TARGET_TYPE has been extracted from BINFO, and, is therefore always
294 cv-unqualified. Extract the cv-qualifiers from EXPR so that the
295 expression returned matches the input. */
296 target_type = cp_build_qualified_type
297 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
298 ptr_target_type = build_pointer_type (target_type);
300 /* Do we need to look in the vtable for the real offset? */
301 virtual_access = (v_binfo && fixed_type_p <= 0);
303 /* Don't bother with the calculations inside sizeof; they'll ICE if the
304 source type is incomplete and the pointer value doesn't matter. */
305 if (cp_unevaluated_operand != 0)
307 expr = build_nop (ptr_target_type, expr);
309 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
313 /* Do we need to check for a null pointer? */
314 if (want_pointer && !nonnull)
316 /* If we know the conversion will not actually change the value
317 of EXPR, then we can avoid testing the expression for NULL.
318 We have to avoid generating a COMPONENT_REF for a base class
319 field, because other parts of the compiler know that such
320 expressions are always non-NULL. */
321 if (!virtual_access && integer_zerop (offset))
322 return build_nop (ptr_target_type, expr);
323 null_test = error_mark_node;
326 /* Protect against multiple evaluation if necessary. */
327 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
328 expr = save_expr (expr);
330 /* Now that we've saved expr, build the real null test. */
333 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
334 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
338 /* If this is a simple base reference, express it as a COMPONENT_REF. */
339 if (code == PLUS_EXPR && !virtual_access
340 /* We don't build base fields for empty bases, and they aren't very
341 interesting to the optimizers anyway. */
344 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
345 expr = build_simple_base_path (expr, binfo);
347 expr = build_address (expr);
348 target_type = TREE_TYPE (expr);
354 /* Going via virtual base V_BINFO. We need the static offset
355 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
356 V_BINFO. That offset is an entry in D_BINFO's vtable. */
359 if (fixed_type_p < 0 && in_base_initializer)
361 /* In a base member initializer, we cannot rely on the
362 vtable being set up. We have to indirect via the
366 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
367 t = build_pointer_type (t);
368 v_offset = convert (t, current_vtt_parm);
369 v_offset = cp_build_indirect_ref (v_offset, RO_NULL,
370 tf_warning_or_error);
373 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, RO_NULL,
374 tf_warning_or_error),
375 TREE_TYPE (TREE_TYPE (expr)));
377 v_offset = build2 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
378 v_offset, fold_convert (sizetype, BINFO_VPTR_FIELD (v_binfo)));
379 v_offset = build1 (NOP_EXPR,
380 build_pointer_type (ptrdiff_type_node),
382 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, tf_warning_or_error);
383 TREE_CONSTANT (v_offset) = 1;
385 offset = convert_to_integer (ptrdiff_type_node,
386 size_diffop_loc (input_location, offset,
387 BINFO_OFFSET (v_binfo)));
389 if (!integer_zerop (offset))
390 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
392 if (fixed_type_p < 0)
393 /* Negative fixed_type_p means this is a constructor or destructor;
394 virtual base layout is fixed in in-charge [cd]tors, but not in
396 offset = build3 (COND_EXPR, ptrdiff_type_node,
397 build2 (EQ_EXPR, boolean_type_node,
398 current_in_charge_parm, integer_zero_node),
400 convert_to_integer (ptrdiff_type_node,
401 BINFO_OFFSET (binfo)));
407 target_type = ptr_target_type;
409 expr = build1 (NOP_EXPR, ptr_target_type, expr);
411 if (!integer_zerop (offset))
413 offset = fold_convert (sizetype, offset);
414 if (code == MINUS_EXPR)
415 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
416 expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
422 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
426 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
427 build_zero_cst (target_type));
432 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
433 Perform a derived-to-base conversion by recursively building up a
434 sequence of COMPONENT_REFs to the appropriate base fields. */
437 build_simple_base_path (tree expr, tree binfo)
439 tree type = BINFO_TYPE (binfo);
440 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
443 if (d_binfo == NULL_TREE)
447 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
449 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
450 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
451 an lvalue in the front end; only _DECLs and _REFs are lvalues
453 temp = unary_complex_lvalue (ADDR_EXPR, expr);
455 expr = cp_build_indirect_ref (temp, RO_NULL, tf_warning_or_error);
461 expr = build_simple_base_path (expr, d_binfo);
463 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
464 field; field = DECL_CHAIN (field))
465 /* Is this the base field created by build_base_field? */
466 if (TREE_CODE (field) == FIELD_DECL
467 && DECL_FIELD_IS_BASE (field)
468 && TREE_TYPE (field) == type)
470 /* We don't use build_class_member_access_expr here, as that
471 has unnecessary checks, and more importantly results in
472 recursive calls to dfs_walk_once. */
473 int type_quals = cp_type_quals (TREE_TYPE (expr));
475 expr = build3 (COMPONENT_REF,
476 cp_build_qualified_type (type, type_quals),
477 expr, field, NULL_TREE);
478 expr = fold_if_not_in_template (expr);
480 /* Mark the expression const or volatile, as appropriate.
481 Even though we've dealt with the type above, we still have
482 to mark the expression itself. */
483 if (type_quals & TYPE_QUAL_CONST)
484 TREE_READONLY (expr) = 1;
485 if (type_quals & TYPE_QUAL_VOLATILE)
486 TREE_THIS_VOLATILE (expr) = 1;
491 /* Didn't find the base field?!? */
495 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
496 type is a class type or a pointer to a class type. In the former
497 case, TYPE is also a class type; in the latter it is another
498 pointer type. If CHECK_ACCESS is true, an error message is emitted
499 if TYPE is inaccessible. If OBJECT has pointer type, the value is
500 assumed to be non-NULL. */
503 convert_to_base (tree object, tree type, bool check_access, bool nonnull,
504 tsubst_flags_t complain)
510 if (TYPE_PTR_P (TREE_TYPE (object)))
512 object_type = TREE_TYPE (TREE_TYPE (object));
513 type = TREE_TYPE (type);
516 object_type = TREE_TYPE (object);
518 access = check_access ? ba_check : ba_unique;
519 if (!(complain & tf_error))
521 binfo = lookup_base (object_type, type,
524 if (!binfo || binfo == error_mark_node)
525 return error_mark_node;
527 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
530 /* EXPR is an expression with unqualified class type. BASE is a base
531 binfo of that class type. Returns EXPR, converted to the BASE
532 type. This function assumes that EXPR is the most derived class;
533 therefore virtual bases can be found at their static offsets. */
536 convert_to_base_statically (tree expr, tree base)
540 expr_type = TREE_TYPE (expr);
541 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
545 pointer_type = build_pointer_type (expr_type);
547 /* We use fold_build2 and fold_convert below to simplify the trees
548 provided to the optimizers. It is not safe to call these functions
549 when processing a template because they do not handle C++-specific
551 gcc_assert (!processing_template_decl);
552 expr = cp_build_addr_expr (expr, tf_warning_or_error);
553 if (!integer_zerop (BINFO_OFFSET (base)))
554 expr = fold_build2_loc (input_location,
555 POINTER_PLUS_EXPR, pointer_type, expr,
556 fold_convert (sizetype, BINFO_OFFSET (base)));
557 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
558 expr = build_fold_indirect_ref_loc (input_location, expr);
566 build_vfield_ref (tree datum, tree type)
568 tree vfield, vcontext;
570 if (datum == error_mark_node)
571 return error_mark_node;
573 /* First, convert to the requested type. */
574 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
575 datum = convert_to_base (datum, type, /*check_access=*/false,
576 /*nonnull=*/true, tf_warning_or_error);
578 /* Second, the requested type may not be the owner of its own vptr.
579 If not, convert to the base class that owns it. We cannot use
580 convert_to_base here, because VCONTEXT may appear more than once
581 in the inheritance hierarchy of TYPE, and thus direct conversion
582 between the types may be ambiguous. Following the path back up
583 one step at a time via primary bases avoids the problem. */
584 vfield = TYPE_VFIELD (type);
585 vcontext = DECL_CONTEXT (vfield);
586 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
588 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
589 type = TREE_TYPE (datum);
592 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
595 /* Given an object INSTANCE, return an expression which yields the
596 vtable element corresponding to INDEX. There are many special
597 cases for INSTANCE which we take care of here, mainly to avoid
598 creating extra tree nodes when we don't have to. */
601 build_vtbl_ref_1 (tree instance, tree idx)
604 tree vtbl = NULL_TREE;
606 /* Try to figure out what a reference refers to, and
607 access its virtual function table directly. */
610 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
612 tree basetype = non_reference (TREE_TYPE (instance));
614 if (fixed_type && !cdtorp)
616 tree binfo = lookup_base (fixed_type, basetype,
617 ba_unique | ba_quiet, NULL);
619 vtbl = unshare_expr (BINFO_VTABLE (binfo));
623 vtbl = build_vfield_ref (instance, basetype);
625 aref = build_array_ref (input_location, vtbl, idx);
626 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
632 build_vtbl_ref (tree instance, tree idx)
634 tree aref = build_vtbl_ref_1 (instance, idx);
639 /* Given a stable object pointer INSTANCE_PTR, return an expression which
640 yields a function pointer corresponding to vtable element INDEX. */
643 build_vfn_ref (tree instance_ptr, tree idx)
647 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, RO_NULL,
648 tf_warning_or_error),
651 /* When using function descriptors, the address of the
652 vtable entry is treated as a function pointer. */
653 if (TARGET_VTABLE_USES_DESCRIPTORS)
654 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
655 cp_build_addr_expr (aref, tf_warning_or_error));
657 /* Remember this as a method reference, for later devirtualization. */
658 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
663 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
664 for the given TYPE. */
667 get_vtable_name (tree type)
669 return mangle_vtbl_for_type (type);
672 /* DECL is an entity associated with TYPE, like a virtual table or an
673 implicitly generated constructor. Determine whether or not DECL
674 should have external or internal linkage at the object file
675 level. This routine does not deal with COMDAT linkage and other
676 similar complexities; it simply sets TREE_PUBLIC if it possible for
677 entities in other translation units to contain copies of DECL, in
681 set_linkage_according_to_type (tree type ATTRIBUTE_UNUSED, tree decl)
683 TREE_PUBLIC (decl) = 1;
684 determine_visibility (decl);
687 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
688 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
689 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
692 build_vtable (tree class_type, tree name, tree vtable_type)
696 decl = build_lang_decl (VAR_DECL, name, vtable_type);
697 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
698 now to avoid confusion in mangle_decl. */
699 SET_DECL_ASSEMBLER_NAME (decl, name);
700 DECL_CONTEXT (decl) = class_type;
701 DECL_ARTIFICIAL (decl) = 1;
702 TREE_STATIC (decl) = 1;
703 TREE_READONLY (decl) = 1;
704 DECL_VIRTUAL_P (decl) = 1;
705 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
706 DECL_VTABLE_OR_VTT_P (decl) = 1;
707 /* At one time the vtable info was grabbed 2 words at a time. This
708 fails on sparc unless you have 8-byte alignment. (tiemann) */
709 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
711 set_linkage_according_to_type (class_type, decl);
712 /* The vtable has not been defined -- yet. */
713 DECL_EXTERNAL (decl) = 1;
714 DECL_NOT_REALLY_EXTERN (decl) = 1;
716 /* Mark the VAR_DECL node representing the vtable itself as a
717 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
718 is rather important that such things be ignored because any
719 effort to actually generate DWARF for them will run into
720 trouble when/if we encounter code like:
723 struct S { virtual void member (); };
725 because the artificial declaration of the vtable itself (as
726 manufactured by the g++ front end) will say that the vtable is
727 a static member of `S' but only *after* the debug output for
728 the definition of `S' has already been output. This causes
729 grief because the DWARF entry for the definition of the vtable
730 will try to refer back to an earlier *declaration* of the
731 vtable as a static member of `S' and there won't be one. We
732 might be able to arrange to have the "vtable static member"
733 attached to the member list for `S' before the debug info for
734 `S' get written (which would solve the problem) but that would
735 require more intrusive changes to the g++ front end. */
736 DECL_IGNORED_P (decl) = 1;
741 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
742 or even complete. If this does not exist, create it. If COMPLETE is
743 nonzero, then complete the definition of it -- that will render it
744 impossible to actually build the vtable, but is useful to get at those
745 which are known to exist in the runtime. */
748 get_vtable_decl (tree type, int complete)
752 if (CLASSTYPE_VTABLES (type))
753 return CLASSTYPE_VTABLES (type);
755 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
756 CLASSTYPE_VTABLES (type) = decl;
760 DECL_EXTERNAL (decl) = 1;
761 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
767 /* Build the primary virtual function table for TYPE. If BINFO is
768 non-NULL, build the vtable starting with the initial approximation
769 that it is the same as the one which is the head of the association
770 list. Returns a nonzero value if a new vtable is actually
774 build_primary_vtable (tree binfo, tree type)
779 decl = get_vtable_decl (type, /*complete=*/0);
783 if (BINFO_NEW_VTABLE_MARKED (binfo))
784 /* We have already created a vtable for this base, so there's
785 no need to do it again. */
788 virtuals = copy_list (BINFO_VIRTUALS (binfo));
789 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
790 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
791 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
795 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
796 virtuals = NULL_TREE;
799 #ifdef GATHER_STATISTICS
801 n_vtable_elems += list_length (virtuals);
804 /* Initialize the association list for this type, based
805 on our first approximation. */
806 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
807 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
808 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
812 /* Give BINFO a new virtual function table which is initialized
813 with a skeleton-copy of its original initialization. The only
814 entry that changes is the `delta' entry, so we can really
815 share a lot of structure.
817 FOR_TYPE is the most derived type which caused this table to
820 Returns nonzero if we haven't met BINFO before.
822 The order in which vtables are built (by calling this function) for
823 an object must remain the same, otherwise a binary incompatibility
827 build_secondary_vtable (tree binfo)
829 if (BINFO_NEW_VTABLE_MARKED (binfo))
830 /* We already created a vtable for this base. There's no need to
834 /* Remember that we've created a vtable for this BINFO, so that we
835 don't try to do so again. */
836 SET_BINFO_NEW_VTABLE_MARKED (binfo);
838 /* Make fresh virtual list, so we can smash it later. */
839 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
841 /* Secondary vtables are laid out as part of the same structure as
842 the primary vtable. */
843 BINFO_VTABLE (binfo) = NULL_TREE;
847 /* Create a new vtable for BINFO which is the hierarchy dominated by
848 T. Return nonzero if we actually created a new vtable. */
851 make_new_vtable (tree t, tree binfo)
853 if (binfo == TYPE_BINFO (t))
854 /* In this case, it is *type*'s vtable we are modifying. We start
855 with the approximation that its vtable is that of the
856 immediate base class. */
857 return build_primary_vtable (binfo, t);
859 /* This is our very own copy of `basetype' to play with. Later,
860 we will fill in all the virtual functions that override the
861 virtual functions in these base classes which are not defined
862 by the current type. */
863 return build_secondary_vtable (binfo);
866 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
867 (which is in the hierarchy dominated by T) list FNDECL as its
868 BV_FN. DELTA is the required constant adjustment from the `this'
869 pointer where the vtable entry appears to the `this' required when
870 the function is actually called. */
873 modify_vtable_entry (tree t,
883 if (fndecl != BV_FN (v)
884 || !tree_int_cst_equal (delta, BV_DELTA (v)))
886 /* We need a new vtable for BINFO. */
887 if (make_new_vtable (t, binfo))
889 /* If we really did make a new vtable, we also made a copy
890 of the BINFO_VIRTUALS list. Now, we have to find the
891 corresponding entry in that list. */
892 *virtuals = BINFO_VIRTUALS (binfo);
893 while (BV_FN (*virtuals) != BV_FN (v))
894 *virtuals = TREE_CHAIN (*virtuals);
898 BV_DELTA (v) = delta;
899 BV_VCALL_INDEX (v) = NULL_TREE;
905 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
906 the USING_DECL naming METHOD. Returns true if the method could be
907 added to the method vec. */
910 add_method (tree type, tree method, tree using_decl)
914 bool template_conv_p = false;
916 VEC(tree,gc) *method_vec;
918 bool insert_p = false;
922 if (method == error_mark_node)
925 complete_p = COMPLETE_TYPE_P (type);
926 conv_p = DECL_CONV_FN_P (method);
928 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
929 && DECL_TEMPLATE_CONV_FN_P (method));
931 method_vec = CLASSTYPE_METHOD_VEC (type);
934 /* Make a new method vector. We start with 8 entries. We must
935 allocate at least two (for constructors and destructors), and
936 we're going to end up with an assignment operator at some
938 method_vec = VEC_alloc (tree, gc, 8);
939 /* Create slots for constructors and destructors. */
940 VEC_quick_push (tree, method_vec, NULL_TREE);
941 VEC_quick_push (tree, method_vec, NULL_TREE);
942 CLASSTYPE_METHOD_VEC (type) = method_vec;
945 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
946 grok_special_member_properties (method);
948 /* Constructors and destructors go in special slots. */
949 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
950 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
951 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
953 slot = CLASSTYPE_DESTRUCTOR_SLOT;
955 if (TYPE_FOR_JAVA (type))
957 if (!DECL_ARTIFICIAL (method))
958 error ("Java class %qT cannot have a destructor", type);
959 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
960 error ("Java class %qT cannot have an implicit non-trivial "
970 /* See if we already have an entry with this name. */
971 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
972 VEC_iterate (tree, method_vec, slot, m);
978 if (TREE_CODE (m) == TEMPLATE_DECL
979 && DECL_TEMPLATE_CONV_FN_P (m))
983 if (conv_p && !DECL_CONV_FN_P (m))
985 if (DECL_NAME (m) == DECL_NAME (method))
991 && !DECL_CONV_FN_P (m)
992 && DECL_NAME (m) > DECL_NAME (method))
996 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
998 /* Check to see if we've already got this method. */
999 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1001 tree fn = OVL_CURRENT (fns);
1007 if (TREE_CODE (fn) != TREE_CODE (method))
1010 /* [over.load] Member function declarations with the
1011 same name and the same parameter types cannot be
1012 overloaded if any of them is a static member
1013 function declaration.
1015 [namespace.udecl] When a using-declaration brings names
1016 from a base class into a derived class scope, member
1017 functions in the derived class override and/or hide member
1018 functions with the same name and parameter types in a base
1019 class (rather than conflicting). */
1020 fn_type = TREE_TYPE (fn);
1021 method_type = TREE_TYPE (method);
1022 parms1 = TYPE_ARG_TYPES (fn_type);
1023 parms2 = TYPE_ARG_TYPES (method_type);
1025 /* Compare the quals on the 'this' parm. Don't compare
1026 the whole types, as used functions are treated as
1027 coming from the using class in overload resolution. */
1028 if (! DECL_STATIC_FUNCTION_P (fn)
1029 && ! DECL_STATIC_FUNCTION_P (method)
1030 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1031 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1032 && (cp_type_quals (TREE_TYPE (TREE_VALUE (parms1)))
1033 != cp_type_quals (TREE_TYPE (TREE_VALUE (parms2)))))
1036 /* For templates, the return type and template parameters
1037 must be identical. */
1038 if (TREE_CODE (fn) == TEMPLATE_DECL
1039 && (!same_type_p (TREE_TYPE (fn_type),
1040 TREE_TYPE (method_type))
1041 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1042 DECL_TEMPLATE_PARMS (method))))
1045 if (! DECL_STATIC_FUNCTION_P (fn))
1046 parms1 = TREE_CHAIN (parms1);
1047 if (! DECL_STATIC_FUNCTION_P (method))
1048 parms2 = TREE_CHAIN (parms2);
1050 if (compparms (parms1, parms2)
1051 && (!DECL_CONV_FN_P (fn)
1052 || same_type_p (TREE_TYPE (fn_type),
1053 TREE_TYPE (method_type))))
1057 if (DECL_CONTEXT (fn) == type)
1058 /* Defer to the local function. */
1060 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1061 error ("repeated using declaration %q+D", using_decl);
1063 error ("using declaration %q+D conflicts with a previous using declaration",
1068 error ("%q+#D cannot be overloaded", method);
1069 error ("with %q+#D", fn);
1072 /* We don't call duplicate_decls here to merge the
1073 declarations because that will confuse things if the
1074 methods have inline definitions. In particular, we
1075 will crash while processing the definitions. */
1080 /* A class should never have more than one destructor. */
1081 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1084 /* Add the new binding. */
1085 overload = build_overload (method, current_fns);
1088 TYPE_HAS_CONVERSION (type) = 1;
1089 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1090 push_class_level_binding (DECL_NAME (method), overload);
1096 /* We only expect to add few methods in the COMPLETE_P case, so
1097 just make room for one more method in that case. */
1099 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1101 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1103 CLASSTYPE_METHOD_VEC (type) = method_vec;
1104 if (slot == VEC_length (tree, method_vec))
1105 VEC_quick_push (tree, method_vec, overload);
1107 VEC_quick_insert (tree, method_vec, slot, overload);
1110 /* Replace the current slot. */
1111 VEC_replace (tree, method_vec, slot, overload);
1115 /* Subroutines of finish_struct. */
1117 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1118 legit, otherwise return 0. */
1121 alter_access (tree t, tree fdecl, tree access)
1125 if (!DECL_LANG_SPECIFIC (fdecl))
1126 retrofit_lang_decl (fdecl);
1128 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1130 elem = purpose_member (t, DECL_ACCESS (fdecl));
1133 if (TREE_VALUE (elem) != access)
1135 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1136 error ("conflicting access specifications for method"
1137 " %q+D, ignored", TREE_TYPE (fdecl));
1139 error ("conflicting access specifications for field %qE, ignored",
1144 /* They're changing the access to the same thing they changed
1145 it to before. That's OK. */
1151 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1152 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1158 /* Process the USING_DECL, which is a member of T. */
1161 handle_using_decl (tree using_decl, tree t)
1163 tree decl = USING_DECL_DECLS (using_decl);
1164 tree name = DECL_NAME (using_decl);
1166 = TREE_PRIVATE (using_decl) ? access_private_node
1167 : TREE_PROTECTED (using_decl) ? access_protected_node
1168 : access_public_node;
1169 tree flist = NULL_TREE;
1172 gcc_assert (!processing_template_decl && decl);
1174 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1177 if (is_overloaded_fn (old_value))
1178 old_value = OVL_CURRENT (old_value);
1180 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1183 old_value = NULL_TREE;
1186 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1188 if (is_overloaded_fn (decl))
1193 else if (is_overloaded_fn (old_value))
1196 /* It's OK to use functions from a base when there are functions with
1197 the same name already present in the current class. */;
1200 error ("%q+D invalid in %q#T", using_decl, t);
1201 error (" because of local method %q+#D with same name",
1202 OVL_CURRENT (old_value));
1206 else if (!DECL_ARTIFICIAL (old_value))
1208 error ("%q+D invalid in %q#T", using_decl, t);
1209 error (" because of local member %q+#D with same name", old_value);
1213 /* Make type T see field decl FDECL with access ACCESS. */
1215 for (; flist; flist = OVL_NEXT (flist))
1217 add_method (t, OVL_CURRENT (flist), using_decl);
1218 alter_access (t, OVL_CURRENT (flist), access);
1221 alter_access (t, decl, access);
1224 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1225 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1226 properties of the bases. */
1229 check_bases (tree t,
1230 int* cant_have_const_ctor_p,
1231 int* no_const_asn_ref_p)
1234 int seen_non_virtual_nearly_empty_base_p;
1237 tree field = NULL_TREE;
1239 seen_non_virtual_nearly_empty_base_p = 0;
1241 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1242 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
1243 if (TREE_CODE (field) == FIELD_DECL)
1246 for (binfo = TYPE_BINFO (t), i = 0;
1247 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1249 tree basetype = TREE_TYPE (base_binfo);
1251 gcc_assert (COMPLETE_TYPE_P (basetype));
1253 if (CLASSTYPE_FINAL (basetype))
1254 error ("cannot derive from %<final%> base %qT in derived type %qT",
1257 /* If any base class is non-literal, so is the derived class. */
1258 if (!CLASSTYPE_LITERAL_P (basetype))
1259 CLASSTYPE_LITERAL_P (t) = false;
1261 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1262 here because the case of virtual functions but non-virtual
1263 dtor is handled in finish_struct_1. */
1264 if (!TYPE_POLYMORPHIC_P (basetype))
1265 warning (OPT_Weffc__,
1266 "base class %q#T has a non-virtual destructor", basetype);
1268 /* If the base class doesn't have copy constructors or
1269 assignment operators that take const references, then the
1270 derived class cannot have such a member automatically
1272 if (TYPE_HAS_COPY_CTOR (basetype)
1273 && ! TYPE_HAS_CONST_COPY_CTOR (basetype))
1274 *cant_have_const_ctor_p = 1;
1275 if (TYPE_HAS_COPY_ASSIGN (basetype)
1276 && !TYPE_HAS_CONST_COPY_ASSIGN (basetype))
1277 *no_const_asn_ref_p = 1;
1279 if (BINFO_VIRTUAL_P (base_binfo))
1280 /* A virtual base does not effect nearly emptiness. */
1282 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1284 if (seen_non_virtual_nearly_empty_base_p)
1285 /* And if there is more than one nearly empty base, then the
1286 derived class is not nearly empty either. */
1287 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1289 /* Remember we've seen one. */
1290 seen_non_virtual_nearly_empty_base_p = 1;
1292 else if (!is_empty_class (basetype))
1293 /* If the base class is not empty or nearly empty, then this
1294 class cannot be nearly empty. */
1295 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1297 /* A lot of properties from the bases also apply to the derived
1299 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1300 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1301 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1302 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
1303 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (basetype)
1304 || !TYPE_HAS_COPY_ASSIGN (basetype));
1305 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (basetype)
1306 || !TYPE_HAS_COPY_CTOR (basetype));
1307 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t)
1308 |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (basetype);
1309 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (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_DEFAULT_CONSTRUCTOR (basetype)
1314 || TYPE_HAS_COMPLEX_DFLT (basetype));
1316 /* A standard-layout class is a class that:
1318 * has no non-standard-layout base classes, */
1319 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1320 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1323 /* ...has no base classes of the same type as the first non-static
1325 if (field && DECL_CONTEXT (field) == t
1326 && (same_type_ignoring_top_level_qualifiers_p
1327 (TREE_TYPE (field), basetype)))
1328 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1330 /* ...either has no non-static data members in the most-derived
1331 class and at most one base class with non-static data
1332 members, or has no base classes with non-static data
1334 for (basefield = TYPE_FIELDS (basetype); basefield;
1335 basefield = DECL_CHAIN (basefield))
1336 if (TREE_CODE (basefield) == FIELD_DECL)
1339 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1348 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1349 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1350 that have had a nearly-empty virtual primary base stolen by some
1351 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1355 determine_primary_bases (tree t)
1358 tree primary = NULL_TREE;
1359 tree type_binfo = TYPE_BINFO (t);
1362 /* Determine the primary bases of our bases. */
1363 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1364 base_binfo = TREE_CHAIN (base_binfo))
1366 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1368 /* See if we're the non-virtual primary of our inheritance
1370 if (!BINFO_VIRTUAL_P (base_binfo))
1372 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1373 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1376 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1377 BINFO_TYPE (parent_primary)))
1378 /* We are the primary binfo. */
1379 BINFO_PRIMARY_P (base_binfo) = 1;
1381 /* Determine if we have a virtual primary base, and mark it so.
1383 if (primary && BINFO_VIRTUAL_P (primary))
1385 tree this_primary = copied_binfo (primary, base_binfo);
1387 if (BINFO_PRIMARY_P (this_primary))
1388 /* Someone already claimed this base. */
1389 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1394 BINFO_PRIMARY_P (this_primary) = 1;
1395 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1397 /* A virtual binfo might have been copied from within
1398 another hierarchy. As we're about to use it as a
1399 primary base, make sure the offsets match. */
1400 delta = size_diffop_loc (input_location,
1402 BINFO_OFFSET (base_binfo)),
1404 BINFO_OFFSET (this_primary)));
1406 propagate_binfo_offsets (this_primary, delta);
1411 /* First look for a dynamic direct non-virtual base. */
1412 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1414 tree basetype = BINFO_TYPE (base_binfo);
1416 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1418 primary = base_binfo;
1423 /* A "nearly-empty" virtual base class can be the primary base
1424 class, if no non-virtual polymorphic base can be found. Look for
1425 a nearly-empty virtual dynamic base that is not already a primary
1426 base of something in the hierarchy. If there is no such base,
1427 just pick the first nearly-empty virtual base. */
1429 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1430 base_binfo = TREE_CHAIN (base_binfo))
1431 if (BINFO_VIRTUAL_P (base_binfo)
1432 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1434 if (!BINFO_PRIMARY_P (base_binfo))
1436 /* Found one that is not primary. */
1437 primary = base_binfo;
1441 /* Remember the first candidate. */
1442 primary = base_binfo;
1446 /* If we've got a primary base, use it. */
1449 tree basetype = BINFO_TYPE (primary);
1451 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1452 if (BINFO_PRIMARY_P (primary))
1453 /* We are stealing a primary base. */
1454 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1455 BINFO_PRIMARY_P (primary) = 1;
1456 if (BINFO_VIRTUAL_P (primary))
1460 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1461 /* A virtual binfo might have been copied from within
1462 another hierarchy. As we're about to use it as a primary
1463 base, make sure the offsets match. */
1464 delta = size_diffop_loc (input_location, ssize_int (0),
1465 convert (ssizetype, BINFO_OFFSET (primary)));
1467 propagate_binfo_offsets (primary, delta);
1470 primary = TYPE_BINFO (basetype);
1472 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1473 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1474 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1478 /* Update the variant types of T. */
1481 fixup_type_variants (tree t)
1488 for (variants = TYPE_NEXT_VARIANT (t);
1490 variants = TYPE_NEXT_VARIANT (variants))
1492 /* These fields are in the _TYPE part of the node, not in
1493 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1494 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1495 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1496 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1497 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1499 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1501 TYPE_BINFO (variants) = TYPE_BINFO (t);
1503 /* Copy whatever these are holding today. */
1504 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1505 TYPE_METHODS (variants) = TYPE_METHODS (t);
1506 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1510 /* Early variant fixups: we apply attributes at the beginning of the class
1511 definition, and we need to fix up any variants that have already been
1512 made via elaborated-type-specifier so that check_qualified_type works. */
1515 fixup_attribute_variants (tree t)
1522 for (variants = TYPE_NEXT_VARIANT (t);
1524 variants = TYPE_NEXT_VARIANT (variants))
1526 /* These are the two fields that check_qualified_type looks at and
1527 are affected by attributes. */
1528 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1529 TYPE_ALIGN (variants) = TYPE_ALIGN (t);
1533 /* Set memoizing fields and bits of T (and its variants) for later
1537 finish_struct_bits (tree t)
1539 /* Fix up variants (if any). */
1540 fixup_type_variants (t);
1542 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1543 /* For a class w/o baseclasses, 'finish_struct' has set
1544 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1545 Similarly for a class whose base classes do not have vtables.
1546 When neither of these is true, we might have removed abstract
1547 virtuals (by providing a definition), added some (by declaring
1548 new ones), or redeclared ones from a base class. We need to
1549 recalculate what's really an abstract virtual at this point (by
1550 looking in the vtables). */
1551 get_pure_virtuals (t);
1553 /* If this type has a copy constructor or a destructor, force its
1554 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1555 nonzero. This will cause it to be passed by invisible reference
1556 and prevent it from being returned in a register. */
1557 if (type_has_nontrivial_copy_init (t)
1558 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1561 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1562 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1564 SET_TYPE_MODE (variants, BLKmode);
1565 TREE_ADDRESSABLE (variants) = 1;
1570 /* Issue warnings about T having private constructors, but no friends,
1573 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1574 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1575 non-private static member functions. */
1578 maybe_warn_about_overly_private_class (tree t)
1580 int has_member_fn = 0;
1581 int has_nonprivate_method = 0;
1584 if (!warn_ctor_dtor_privacy
1585 /* If the class has friends, those entities might create and
1586 access instances, so we should not warn. */
1587 || (CLASSTYPE_FRIEND_CLASSES (t)
1588 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1589 /* We will have warned when the template was declared; there's
1590 no need to warn on every instantiation. */
1591 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1592 /* There's no reason to even consider warning about this
1596 /* We only issue one warning, if more than one applies, because
1597 otherwise, on code like:
1600 // Oops - forgot `public:'
1606 we warn several times about essentially the same problem. */
1608 /* Check to see if all (non-constructor, non-destructor) member
1609 functions are private. (Since there are no friends or
1610 non-private statics, we can't ever call any of the private member
1612 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
1613 /* We're not interested in compiler-generated methods; they don't
1614 provide any way to call private members. */
1615 if (!DECL_ARTIFICIAL (fn))
1617 if (!TREE_PRIVATE (fn))
1619 if (DECL_STATIC_FUNCTION_P (fn))
1620 /* A non-private static member function is just like a
1621 friend; it can create and invoke private member
1622 functions, and be accessed without a class
1626 has_nonprivate_method = 1;
1627 /* Keep searching for a static member function. */
1629 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1633 if (!has_nonprivate_method && has_member_fn)
1635 /* There are no non-private methods, and there's at least one
1636 private member function that isn't a constructor or
1637 destructor. (If all the private members are
1638 constructors/destructors we want to use the code below that
1639 issues error messages specifically referring to
1640 constructors/destructors.) */
1642 tree binfo = TYPE_BINFO (t);
1644 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1645 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1647 has_nonprivate_method = 1;
1650 if (!has_nonprivate_method)
1652 warning (OPT_Wctor_dtor_privacy,
1653 "all member functions in class %qT are private", t);
1658 /* Even if some of the member functions are non-private, the class
1659 won't be useful for much if all the constructors or destructors
1660 are private: such an object can never be created or destroyed. */
1661 fn = CLASSTYPE_DESTRUCTORS (t);
1662 if (fn && TREE_PRIVATE (fn))
1664 warning (OPT_Wctor_dtor_privacy,
1665 "%q#T only defines a private destructor and has no friends",
1670 /* Warn about classes that have private constructors and no friends. */
1671 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1672 /* Implicitly generated constructors are always public. */
1673 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1674 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1676 int nonprivate_ctor = 0;
1678 /* If a non-template class does not define a copy
1679 constructor, one is defined for it, enabling it to avoid
1680 this warning. For a template class, this does not
1681 happen, and so we would normally get a warning on:
1683 template <class T> class C { private: C(); };
1685 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1686 complete non-template or fully instantiated classes have this
1688 if (!TYPE_HAS_COPY_CTOR (t))
1689 nonprivate_ctor = 1;
1691 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1693 tree ctor = OVL_CURRENT (fn);
1694 /* Ideally, we wouldn't count copy constructors (or, in
1695 fact, any constructor that takes an argument of the
1696 class type as a parameter) because such things cannot
1697 be used to construct an instance of the class unless
1698 you already have one. But, for now at least, we're
1700 if (! TREE_PRIVATE (ctor))
1702 nonprivate_ctor = 1;
1707 if (nonprivate_ctor == 0)
1709 warning (OPT_Wctor_dtor_privacy,
1710 "%q#T only defines private constructors and has no friends",
1718 gt_pointer_operator new_value;
1722 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1725 method_name_cmp (const void* m1_p, const void* m2_p)
1727 const tree *const m1 = (const tree *) m1_p;
1728 const tree *const m2 = (const tree *) m2_p;
1730 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1732 if (*m1 == NULL_TREE)
1734 if (*m2 == NULL_TREE)
1736 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1741 /* This routine compares two fields like method_name_cmp but using the
1742 pointer operator in resort_field_decl_data. */
1745 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1747 const tree *const m1 = (const tree *) m1_p;
1748 const tree *const m2 = (const tree *) m2_p;
1749 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1751 if (*m1 == NULL_TREE)
1753 if (*m2 == NULL_TREE)
1756 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1757 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1758 resort_data.new_value (&d1, resort_data.cookie);
1759 resort_data.new_value (&d2, resort_data.cookie);
1766 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1769 resort_type_method_vec (void* obj,
1770 void* orig_obj ATTRIBUTE_UNUSED ,
1771 gt_pointer_operator new_value,
1774 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1775 int len = VEC_length (tree, method_vec);
1779 /* The type conversion ops have to live at the front of the vec, so we
1781 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1782 VEC_iterate (tree, method_vec, slot, fn);
1784 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1789 resort_data.new_value = new_value;
1790 resort_data.cookie = cookie;
1791 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1792 resort_method_name_cmp);
1796 /* Warn about duplicate methods in fn_fields.
1798 Sort methods that are not special (i.e., constructors, destructors,
1799 and type conversion operators) so that we can find them faster in
1803 finish_struct_methods (tree t)
1806 VEC(tree,gc) *method_vec;
1809 method_vec = CLASSTYPE_METHOD_VEC (t);
1813 len = VEC_length (tree, method_vec);
1815 /* Clear DECL_IN_AGGR_P for all functions. */
1816 for (fn_fields = TYPE_METHODS (t); fn_fields;
1817 fn_fields = DECL_CHAIN (fn_fields))
1818 DECL_IN_AGGR_P (fn_fields) = 0;
1820 /* Issue warnings about private constructors and such. If there are
1821 no methods, then some public defaults are generated. */
1822 maybe_warn_about_overly_private_class (t);
1824 /* The type conversion ops have to live at the front of the vec, so we
1826 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1827 VEC_iterate (tree, method_vec, slot, fn_fields);
1829 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1832 qsort (VEC_address (tree, method_vec) + slot,
1833 len-slot, sizeof (tree), method_name_cmp);
1836 /* Make BINFO's vtable have N entries, including RTTI entries,
1837 vbase and vcall offsets, etc. Set its type and call the back end
1841 layout_vtable_decl (tree binfo, int n)
1846 atype = build_array_of_n_type (vtable_entry_type, n);
1847 layout_type (atype);
1849 /* We may have to grow the vtable. */
1850 vtable = get_vtbl_decl_for_binfo (binfo);
1851 if (!same_type_p (TREE_TYPE (vtable), atype))
1853 TREE_TYPE (vtable) = atype;
1854 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1855 layout_decl (vtable, 0);
1859 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1860 have the same signature. */
1863 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1865 /* One destructor overrides another if they are the same kind of
1867 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1868 && special_function_p (base_fndecl) == special_function_p (fndecl))
1870 /* But a non-destructor never overrides a destructor, nor vice
1871 versa, nor do different kinds of destructors override
1872 one-another. For example, a complete object destructor does not
1873 override a deleting destructor. */
1874 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1877 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1878 || (DECL_CONV_FN_P (fndecl)
1879 && DECL_CONV_FN_P (base_fndecl)
1880 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1881 DECL_CONV_FN_TYPE (base_fndecl))))
1883 tree types, base_types;
1884 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1885 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1886 if ((cp_type_quals (TREE_TYPE (TREE_VALUE (base_types)))
1887 == cp_type_quals (TREE_TYPE (TREE_VALUE (types))))
1888 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1894 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1898 base_derived_from (tree derived, tree base)
1902 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1904 if (probe == derived)
1906 else if (BINFO_VIRTUAL_P (probe))
1907 /* If we meet a virtual base, we can't follow the inheritance
1908 any more. See if the complete type of DERIVED contains
1909 such a virtual base. */
1910 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1916 typedef struct find_final_overrider_data_s {
1917 /* The function for which we are trying to find a final overrider. */
1919 /* The base class in which the function was declared. */
1920 tree declaring_base;
1921 /* The candidate overriders. */
1923 /* Path to most derived. */
1924 VEC(tree,heap) *path;
1925 } find_final_overrider_data;
1927 /* Add the overrider along the current path to FFOD->CANDIDATES.
1928 Returns true if an overrider was found; false otherwise. */
1931 dfs_find_final_overrider_1 (tree binfo,
1932 find_final_overrider_data *ffod,
1937 /* If BINFO is not the most derived type, try a more derived class.
1938 A definition there will overrider a definition here. */
1942 if (dfs_find_final_overrider_1
1943 (VEC_index (tree, ffod->path, depth), ffod, depth))
1947 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1950 tree *candidate = &ffod->candidates;
1952 /* Remove any candidates overridden by this new function. */
1955 /* If *CANDIDATE overrides METHOD, then METHOD
1956 cannot override anything else on the list. */
1957 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1959 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1960 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1961 *candidate = TREE_CHAIN (*candidate);
1963 candidate = &TREE_CHAIN (*candidate);
1966 /* Add the new function. */
1967 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1974 /* Called from find_final_overrider via dfs_walk. */
1977 dfs_find_final_overrider_pre (tree binfo, void *data)
1979 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1981 if (binfo == ffod->declaring_base)
1982 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1983 VEC_safe_push (tree, heap, ffod->path, binfo);
1989 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1991 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1992 VEC_pop (tree, ffod->path);
1997 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1998 FN and whose TREE_VALUE is the binfo for the base where the
1999 overriding occurs. BINFO (in the hierarchy dominated by the binfo
2000 DERIVED) is the base object in which FN is declared. */
2003 find_final_overrider (tree derived, tree binfo, tree fn)
2005 find_final_overrider_data ffod;
2007 /* Getting this right is a little tricky. This is valid:
2009 struct S { virtual void f (); };
2010 struct T { virtual void f (); };
2011 struct U : public S, public T { };
2013 even though calling `f' in `U' is ambiguous. But,
2015 struct R { virtual void f(); };
2016 struct S : virtual public R { virtual void f (); };
2017 struct T : virtual public R { virtual void f (); };
2018 struct U : public S, public T { };
2020 is not -- there's no way to decide whether to put `S::f' or
2021 `T::f' in the vtable for `R'.
2023 The solution is to look at all paths to BINFO. If we find
2024 different overriders along any two, then there is a problem. */
2025 if (DECL_THUNK_P (fn))
2026 fn = THUNK_TARGET (fn);
2028 /* Determine the depth of the hierarchy. */
2030 ffod.declaring_base = binfo;
2031 ffod.candidates = NULL_TREE;
2032 ffod.path = VEC_alloc (tree, heap, 30);
2034 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2035 dfs_find_final_overrider_post, &ffod);
2037 VEC_free (tree, heap, ffod.path);
2039 /* If there was no winner, issue an error message. */
2040 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2041 return error_mark_node;
2043 return ffod.candidates;
2046 /* Return the index of the vcall offset for FN when TYPE is used as a
2050 get_vcall_index (tree fn, tree type)
2052 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2056 FOR_EACH_VEC_ELT (tree_pair_s, indices, ix, p)
2057 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2058 || same_signature_p (fn, p->purpose))
2061 /* There should always be an appropriate index. */
2065 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2066 dominated by T. FN is the old function; VIRTUALS points to the
2067 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2068 of that entry in the list. */
2071 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2079 tree overrider_fn, overrider_target;
2080 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2081 tree over_return, base_return;
2084 /* Find the nearest primary base (possibly binfo itself) which defines
2085 this function; this is the class the caller will convert to when
2086 calling FN through BINFO. */
2087 for (b = binfo; ; b = get_primary_binfo (b))
2090 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2093 /* The nearest definition is from a lost primary. */
2094 if (BINFO_LOST_PRIMARY_P (b))
2099 /* Find the final overrider. */
2100 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2101 if (overrider == error_mark_node)
2103 error ("no unique final overrider for %qD in %qT", target_fn, t);
2106 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2108 /* Check for adjusting covariant return types. */
2109 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2110 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2112 if (POINTER_TYPE_P (over_return)
2113 && TREE_CODE (over_return) == TREE_CODE (base_return)
2114 && CLASS_TYPE_P (TREE_TYPE (over_return))
2115 && CLASS_TYPE_P (TREE_TYPE (base_return))
2116 /* If the overrider is invalid, don't even try. */
2117 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2119 /* If FN is a covariant thunk, we must figure out the adjustment
2120 to the final base FN was converting to. As OVERRIDER_TARGET might
2121 also be converting to the return type of FN, we have to
2122 combine the two conversions here. */
2123 tree fixed_offset, virtual_offset;
2125 over_return = TREE_TYPE (over_return);
2126 base_return = TREE_TYPE (base_return);
2128 if (DECL_THUNK_P (fn))
2130 gcc_assert (DECL_RESULT_THUNK_P (fn));
2131 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2132 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2135 fixed_offset = virtual_offset = NULL_TREE;
2138 /* Find the equivalent binfo within the return type of the
2139 overriding function. We will want the vbase offset from
2141 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2143 else if (!same_type_ignoring_top_level_qualifiers_p
2144 (over_return, base_return))
2146 /* There was no existing virtual thunk (which takes
2147 precedence). So find the binfo of the base function's
2148 return type within the overriding function's return type.
2149 We cannot call lookup base here, because we're inside a
2150 dfs_walk, and will therefore clobber the BINFO_MARKED
2151 flags. Fortunately we know the covariancy is valid (it
2152 has already been checked), so we can just iterate along
2153 the binfos, which have been chained in inheritance graph
2154 order. Of course it is lame that we have to repeat the
2155 search here anyway -- we should really be caching pieces
2156 of the vtable and avoiding this repeated work. */
2157 tree thunk_binfo, base_binfo;
2159 /* Find the base binfo within the overriding function's
2160 return type. We will always find a thunk_binfo, except
2161 when the covariancy is invalid (which we will have
2162 already diagnosed). */
2163 for (base_binfo = TYPE_BINFO (base_return),
2164 thunk_binfo = TYPE_BINFO (over_return);
2166 thunk_binfo = TREE_CHAIN (thunk_binfo))
2167 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2168 BINFO_TYPE (base_binfo)))
2171 /* See if virtual inheritance is involved. */
2172 for (virtual_offset = thunk_binfo;
2174 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2175 if (BINFO_VIRTUAL_P (virtual_offset))
2179 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2181 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2185 /* We convert via virtual base. Adjust the fixed
2186 offset to be from there. */
2188 size_diffop (offset,
2190 BINFO_OFFSET (virtual_offset)));
2193 /* There was an existing fixed offset, this must be
2194 from the base just converted to, and the base the
2195 FN was thunking to. */
2196 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2198 fixed_offset = offset;
2202 if (fixed_offset || virtual_offset)
2203 /* Replace the overriding function with a covariant thunk. We
2204 will emit the overriding function in its own slot as
2206 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2207 fixed_offset, virtual_offset);
2210 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2211 !DECL_THUNK_P (fn));
2213 /* If we need a covariant thunk, then we may need to adjust first_defn.
2214 The ABI specifies that the thunks emitted with a function are
2215 determined by which bases the function overrides, so we need to be
2216 sure that we're using a thunk for some overridden base; even if we
2217 know that the necessary this adjustment is zero, there may not be an
2218 appropriate zero-this-adjusment thunk for us to use since thunks for
2219 overriding virtual bases always use the vcall offset.
2221 Furthermore, just choosing any base that overrides this function isn't
2222 quite right, as this slot won't be used for calls through a type that
2223 puts a covariant thunk here. Calling the function through such a type
2224 will use a different slot, and that slot is the one that determines
2225 the thunk emitted for that base.
2227 So, keep looking until we find the base that we're really overriding
2228 in this slot: the nearest primary base that doesn't use a covariant
2229 thunk in this slot. */
2230 if (overrider_target != overrider_fn)
2232 if (BINFO_TYPE (b) == DECL_CONTEXT (overrider_target))
2233 /* We already know that the overrider needs a covariant thunk. */
2234 b = get_primary_binfo (b);
2235 for (; ; b = get_primary_binfo (b))
2237 tree main_binfo = TYPE_BINFO (BINFO_TYPE (b));
2238 tree bv = chain_index (ix, BINFO_VIRTUALS (main_binfo));
2239 if (!DECL_THUNK_P (TREE_VALUE (bv)))
2241 if (BINFO_LOST_PRIMARY_P (b))
2247 /* Assume that we will produce a thunk that convert all the way to
2248 the final overrider, and not to an intermediate virtual base. */
2249 virtual_base = NULL_TREE;
2251 /* See if we can convert to an intermediate virtual base first, and then
2252 use the vcall offset located there to finish the conversion. */
2253 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2255 /* If we find the final overrider, then we can stop
2257 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2258 BINFO_TYPE (TREE_VALUE (overrider))))
2261 /* If we find a virtual base, and we haven't yet found the
2262 overrider, then there is a virtual base between the
2263 declaring base (first_defn) and the final overrider. */
2264 if (BINFO_VIRTUAL_P (b))
2271 /* Compute the constant adjustment to the `this' pointer. The
2272 `this' pointer, when this function is called, will point at BINFO
2273 (or one of its primary bases, which are at the same offset). */
2275 /* The `this' pointer needs to be adjusted from the declaration to
2276 the nearest virtual base. */
2277 delta = size_diffop_loc (input_location,
2278 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2279 convert (ssizetype, BINFO_OFFSET (first_defn)));
2281 /* If the nearest definition is in a lost primary, we don't need an
2282 entry in our vtable. Except possibly in a constructor vtable,
2283 if we happen to get our primary back. In that case, the offset
2284 will be zero, as it will be a primary base. */
2285 delta = size_zero_node;
2287 /* The `this' pointer needs to be adjusted from pointing to
2288 BINFO to pointing at the base where the final overrider
2290 delta = size_diffop_loc (input_location,
2292 BINFO_OFFSET (TREE_VALUE (overrider))),
2293 convert (ssizetype, BINFO_OFFSET (binfo)));
2295 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2298 BV_VCALL_INDEX (*virtuals)
2299 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2301 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2304 BV_LOST_PRIMARY (*virtuals) = true;
2307 /* Called from modify_all_vtables via dfs_walk. */
2310 dfs_modify_vtables (tree binfo, void* data)
2312 tree t = (tree) data;
2317 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2318 /* A base without a vtable needs no modification, and its bases
2319 are uninteresting. */
2320 return dfs_skip_bases;
2322 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2323 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2324 /* Don't do the primary vtable, if it's new. */
2327 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2328 /* There's no need to modify the vtable for a non-virtual primary
2329 base; we're not going to use that vtable anyhow. We do still
2330 need to do this for virtual primary bases, as they could become
2331 non-primary in a construction vtable. */
2334 make_new_vtable (t, binfo);
2336 /* Now, go through each of the virtual functions in the virtual
2337 function table for BINFO. Find the final overrider, and update
2338 the BINFO_VIRTUALS list appropriately. */
2339 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2340 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2342 ix++, virtuals = TREE_CHAIN (virtuals),
2343 old_virtuals = TREE_CHAIN (old_virtuals))
2344 update_vtable_entry_for_fn (t,
2346 BV_FN (old_virtuals),
2352 /* Update all of the primary and secondary vtables for T. Create new
2353 vtables as required, and initialize their RTTI information. Each
2354 of the functions in VIRTUALS is declared in T and may override a
2355 virtual function from a base class; find and modify the appropriate
2356 entries to point to the overriding functions. Returns a list, in
2357 declaration order, of the virtual functions that are declared in T,
2358 but do not appear in the primary base class vtable, and which
2359 should therefore be appended to the end of the vtable for T. */
2362 modify_all_vtables (tree t, tree virtuals)
2364 tree binfo = TYPE_BINFO (t);
2367 /* Update all of the vtables. */
2368 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2370 /* Add virtual functions not already in our primary vtable. These
2371 will be both those introduced by this class, and those overridden
2372 from secondary bases. It does not include virtuals merely
2373 inherited from secondary bases. */
2374 for (fnsp = &virtuals; *fnsp; )
2376 tree fn = TREE_VALUE (*fnsp);
2378 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2379 || DECL_VINDEX (fn) == error_mark_node)
2381 /* We don't need to adjust the `this' pointer when
2382 calling this function. */
2383 BV_DELTA (*fnsp) = integer_zero_node;
2384 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2386 /* This is a function not already in our vtable. Keep it. */
2387 fnsp = &TREE_CHAIN (*fnsp);
2390 /* We've already got an entry for this function. Skip it. */
2391 *fnsp = TREE_CHAIN (*fnsp);
2397 /* Get the base virtual function declarations in T that have the
2401 get_basefndecls (tree name, tree t)
2404 tree base_fndecls = NULL_TREE;
2405 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2408 /* Find virtual functions in T with the indicated NAME. */
2409 i = lookup_fnfields_1 (t, name);
2411 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2413 methods = OVL_NEXT (methods))
2415 tree method = OVL_CURRENT (methods);
2417 if (TREE_CODE (method) == FUNCTION_DECL
2418 && DECL_VINDEX (method))
2419 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2423 return base_fndecls;
2425 for (i = 0; i < n_baseclasses; i++)
2427 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2428 base_fndecls = chainon (get_basefndecls (name, basetype),
2432 return base_fndecls;
2435 /* If this declaration supersedes the declaration of
2436 a method declared virtual in the base class, then
2437 mark this field as being virtual as well. */
2440 check_for_override (tree decl, tree ctype)
2442 bool overrides_found = false;
2443 if (TREE_CODE (decl) == TEMPLATE_DECL)
2444 /* In [temp.mem] we have:
2446 A specialization of a member function template does not
2447 override a virtual function from a base class. */
2449 if ((DECL_DESTRUCTOR_P (decl)
2450 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2451 || DECL_CONV_FN_P (decl))
2452 && look_for_overrides (ctype, decl)
2453 && !DECL_STATIC_FUNCTION_P (decl))
2454 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2455 the error_mark_node so that we know it is an overriding
2458 DECL_VINDEX (decl) = decl;
2459 overrides_found = true;
2462 if (DECL_VIRTUAL_P (decl))
2464 if (!DECL_VINDEX (decl))
2465 DECL_VINDEX (decl) = error_mark_node;
2466 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2467 if (DECL_DESTRUCTOR_P (decl))
2468 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (ctype) = true;
2470 else if (DECL_FINAL_P (decl))
2471 error ("%q+#D marked final, but is not virtual", decl);
2472 if (DECL_OVERRIDE_P (decl) && !overrides_found)
2473 error ("%q+#D marked override, but does not override", decl);
2476 /* Warn about hidden virtual functions that are not overridden in t.
2477 We know that constructors and destructors don't apply. */
2480 warn_hidden (tree t)
2482 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2486 /* We go through each separately named virtual function. */
2487 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2488 VEC_iterate (tree, method_vec, i, fns);
2499 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2500 have the same name. Figure out what name that is. */
2501 name = DECL_NAME (OVL_CURRENT (fns));
2502 /* There are no possibly hidden functions yet. */
2503 base_fndecls = NULL_TREE;
2504 /* Iterate through all of the base classes looking for possibly
2505 hidden functions. */
2506 for (binfo = TYPE_BINFO (t), j = 0;
2507 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2509 tree basetype = BINFO_TYPE (base_binfo);
2510 base_fndecls = chainon (get_basefndecls (name, basetype),
2514 /* If there are no functions to hide, continue. */
2518 /* Remove any overridden functions. */
2519 for (fn = fns; fn; fn = OVL_NEXT (fn))
2521 fndecl = OVL_CURRENT (fn);
2522 if (DECL_VINDEX (fndecl))
2524 tree *prev = &base_fndecls;
2527 /* If the method from the base class has the same
2528 signature as the method from the derived class, it
2529 has been overridden. */
2530 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2531 *prev = TREE_CHAIN (*prev);
2533 prev = &TREE_CHAIN (*prev);
2537 /* Now give a warning for all base functions without overriders,
2538 as they are hidden. */
2539 while (base_fndecls)
2541 /* Here we know it is a hider, and no overrider exists. */
2542 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2543 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2544 base_fndecls = TREE_CHAIN (base_fndecls);
2549 /* Check for things that are invalid. There are probably plenty of other
2550 things we should check for also. */
2553 finish_struct_anon (tree t)
2557 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
2559 if (TREE_STATIC (field))
2561 if (TREE_CODE (field) != FIELD_DECL)
2564 if (DECL_NAME (field) == NULL_TREE
2565 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2567 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2568 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2569 for (; elt; elt = DECL_CHAIN (elt))
2571 /* We're generally only interested in entities the user
2572 declared, but we also find nested classes by noticing
2573 the TYPE_DECL that we create implicitly. You're
2574 allowed to put one anonymous union inside another,
2575 though, so we explicitly tolerate that. We use
2576 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2577 we also allow unnamed types used for defining fields. */
2578 if (DECL_ARTIFICIAL (elt)
2579 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2580 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2583 if (TREE_CODE (elt) != FIELD_DECL)
2586 permerror (input_location, "%q+#D invalid; an anonymous union can "
2587 "only have non-static data members", elt);
2589 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2590 "only have non-static data members", elt);
2594 if (TREE_PRIVATE (elt))
2597 permerror (input_location, "private member %q+#D in anonymous union", elt);
2599 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2601 else if (TREE_PROTECTED (elt))
2604 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2606 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2609 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2610 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2616 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2617 will be used later during class template instantiation.
2618 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2619 a non-static member data (FIELD_DECL), a member function
2620 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2621 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2622 When FRIEND_P is nonzero, T is either a friend class
2623 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2624 (FUNCTION_DECL, TEMPLATE_DECL). */
2627 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2629 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2630 if (CLASSTYPE_TEMPLATE_INFO (type))
2631 CLASSTYPE_DECL_LIST (type)
2632 = tree_cons (friend_p ? NULL_TREE : type,
2633 t, CLASSTYPE_DECL_LIST (type));
2636 /* This function is called from declare_virt_assop_and_dtor via
2639 DATA is a type that direcly or indirectly inherits the base
2640 represented by BINFO. If BINFO contains a virtual assignment [copy
2641 assignment or move assigment] operator or a virtual constructor,
2642 declare that function in DATA if it hasn't been already declared. */
2645 dfs_declare_virt_assop_and_dtor (tree binfo, void *data)
2647 tree bv, fn, t = (tree)data;
2648 tree opname = ansi_assopname (NOP_EXPR);
2650 gcc_assert (t && CLASS_TYPE_P (t));
2651 gcc_assert (binfo && TREE_CODE (binfo) == TREE_BINFO);
2653 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2654 /* A base without a vtable needs no modification, and its bases
2655 are uninteresting. */
2656 return dfs_skip_bases;
2658 if (BINFO_PRIMARY_P (binfo))
2659 /* If this is a primary base, then we have already looked at the
2660 virtual functions of its vtable. */
2663 for (bv = BINFO_VIRTUALS (binfo); bv; bv = TREE_CHAIN (bv))
2667 if (DECL_NAME (fn) == opname)
2669 if (CLASSTYPE_LAZY_COPY_ASSIGN (t))
2670 lazily_declare_fn (sfk_copy_assignment, t);
2671 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
2672 lazily_declare_fn (sfk_move_assignment, t);
2674 else if (DECL_DESTRUCTOR_P (fn)
2675 && CLASSTYPE_LAZY_DESTRUCTOR (t))
2676 lazily_declare_fn (sfk_destructor, t);
2682 /* If the class type T has a direct or indirect base that contains a
2683 virtual assignment operator or a virtual destructor, declare that
2684 function in T if it hasn't been already declared. */
2687 declare_virt_assop_and_dtor (tree t)
2689 if (!(TYPE_POLYMORPHIC_P (t)
2690 && (CLASSTYPE_LAZY_COPY_ASSIGN (t)
2691 || CLASSTYPE_LAZY_MOVE_ASSIGN (t)
2692 || CLASSTYPE_LAZY_DESTRUCTOR (t))))
2695 dfs_walk_all (TYPE_BINFO (t),
2696 dfs_declare_virt_assop_and_dtor,
2700 /* Create default constructors, assignment operators, and so forth for
2701 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2702 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2703 the class cannot have a default constructor, copy constructor
2704 taking a const reference argument, or an assignment operator taking
2705 a const reference, respectively. */
2708 add_implicitly_declared_members (tree t,
2709 int cant_have_const_cctor,
2710 int cant_have_const_assignment)
2713 if (!CLASSTYPE_DESTRUCTORS (t))
2715 /* In general, we create destructors lazily. */
2716 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2718 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2719 && TYPE_FOR_JAVA (t))
2720 /* But if this is a Java class, any non-trivial destructor is
2721 invalid, even if compiler-generated. Therefore, if the
2722 destructor is non-trivial we create it now. */
2723 lazily_declare_fn (sfk_destructor, t);
2728 If there is no user-declared constructor for a class, a default
2729 constructor is implicitly declared. */
2730 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2732 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2733 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2734 if (cxx_dialect >= cxx0x)
2735 TYPE_HAS_CONSTEXPR_CTOR (t)
2736 = synthesized_default_constructor_is_constexpr (t);
2741 If a class definition does not explicitly declare a copy
2742 constructor, one is declared implicitly. */
2743 if (! TYPE_HAS_COPY_CTOR (t) && ! TYPE_FOR_JAVA (t)
2744 && !type_has_move_constructor (t))
2746 TYPE_HAS_COPY_CTOR (t) = 1;
2747 TYPE_HAS_CONST_COPY_CTOR (t) = !cant_have_const_cctor;
2748 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2749 if (cxx_dialect >= cxx0x)
2750 CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
2753 /* If there is no assignment operator, one will be created if and
2754 when it is needed. For now, just record whether or not the type
2755 of the parameter to the assignment operator will be a const or
2756 non-const reference. */
2757 if (!TYPE_HAS_COPY_ASSIGN (t) && !TYPE_FOR_JAVA (t)
2758 && !type_has_move_assign (t))
2760 TYPE_HAS_COPY_ASSIGN (t) = 1;
2761 TYPE_HAS_CONST_COPY_ASSIGN (t) = !cant_have_const_assignment;
2762 CLASSTYPE_LAZY_COPY_ASSIGN (t) = 1;
2763 if (cxx_dialect >= cxx0x)
2764 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 1;
2767 /* We can't be lazy about declaring functions that might override
2768 a virtual function from a base class. */
2769 declare_virt_assop_and_dtor (t);
2772 /* Subroutine of finish_struct_1. Recursively count the number of fields
2773 in TYPE, including anonymous union members. */
2776 count_fields (tree fields)
2780 for (x = fields; x; x = DECL_CHAIN (x))
2782 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2783 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2790 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2791 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2794 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2797 for (x = fields; x; x = DECL_CHAIN (x))
2799 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2800 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2802 field_vec->elts[idx++] = x;
2807 /* FIELD is a bit-field. We are finishing the processing for its
2808 enclosing type. Issue any appropriate messages and set appropriate
2809 flags. Returns false if an error has been diagnosed. */
2812 check_bitfield_decl (tree field)
2814 tree type = TREE_TYPE (field);
2817 /* Extract the declared width of the bitfield, which has been
2818 temporarily stashed in DECL_INITIAL. */
2819 w = DECL_INITIAL (field);
2820 gcc_assert (w != NULL_TREE);
2821 /* Remove the bit-field width indicator so that the rest of the
2822 compiler does not treat that value as an initializer. */
2823 DECL_INITIAL (field) = NULL_TREE;
2825 /* Detect invalid bit-field type. */
2826 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2828 error ("bit-field %q+#D with non-integral type", field);
2829 w = error_mark_node;
2833 location_t loc = input_location;
2834 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2837 /* detect invalid field size. */
2838 input_location = DECL_SOURCE_LOCATION (field);
2839 w = cxx_constant_value (w);
2840 input_location = loc;
2842 if (TREE_CODE (w) != INTEGER_CST)
2844 error ("bit-field %q+D width not an integer constant", field);
2845 w = error_mark_node;
2847 else if (tree_int_cst_sgn (w) < 0)
2849 error ("negative width in bit-field %q+D", field);
2850 w = error_mark_node;
2852 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2854 error ("zero width for bit-field %q+D", field);
2855 w = error_mark_node;
2857 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2858 && TREE_CODE (type) != ENUMERAL_TYPE
2859 && TREE_CODE (type) != BOOLEAN_TYPE)
2860 warning (0, "width of %q+D exceeds its type", field);
2861 else if (TREE_CODE (type) == ENUMERAL_TYPE
2862 && (0 > (compare_tree_int
2863 (w, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type))))))
2864 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2867 if (w != error_mark_node)
2869 DECL_SIZE (field) = convert (bitsizetype, w);
2870 DECL_BIT_FIELD (field) = 1;
2875 /* Non-bit-fields are aligned for their type. */
2876 DECL_BIT_FIELD (field) = 0;
2877 CLEAR_DECL_C_BIT_FIELD (field);
2882 /* FIELD is a non bit-field. We are finishing the processing for its
2883 enclosing type T. Issue any appropriate messages and set appropriate
2887 check_field_decl (tree field,
2889 int* cant_have_const_ctor,
2890 int* no_const_asn_ref,
2891 int* any_default_members)
2893 tree type = strip_array_types (TREE_TYPE (field));
2895 /* In C++98 an anonymous union cannot contain any fields which would change
2896 the settings of CANT_HAVE_CONST_CTOR and friends. */
2897 if (ANON_UNION_TYPE_P (type) && cxx_dialect < cxx0x)
2899 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2900 structs. So, we recurse through their fields here. */
2901 else if (ANON_AGGR_TYPE_P (type))
2905 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2906 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2907 check_field_decl (fields, t, cant_have_const_ctor,
2908 no_const_asn_ref, any_default_members);
2910 /* Check members with class type for constructors, destructors,
2912 else if (CLASS_TYPE_P (type))
2914 /* Never let anything with uninheritable virtuals
2915 make it through without complaint. */
2916 abstract_virtuals_error (field, type);
2918 if (TREE_CODE (t) == UNION_TYPE && cxx_dialect < cxx0x)
2921 int oldcount = errorcount;
2922 if (TYPE_NEEDS_CONSTRUCTING (type))
2923 error ("member %q+#D with constructor not allowed in union",
2925 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2926 error ("member %q+#D with destructor not allowed in union", field);
2927 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
2928 error ("member %q+#D with copy assignment operator not allowed in union",
2930 if (!warned && errorcount > oldcount)
2932 inform (DECL_SOURCE_LOCATION (field), "unrestricted unions "
2933 "only available with -std=c++0x or -std=gnu++0x");
2939 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2940 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2941 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2942 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
2943 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type)
2944 || !TYPE_HAS_COPY_ASSIGN (type));
2945 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type)
2946 || !TYPE_HAS_COPY_CTOR (type));
2947 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type);
2948 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type);
2949 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type)
2950 || TYPE_HAS_COMPLEX_DFLT (type));
2953 if (TYPE_HAS_COPY_CTOR (type)
2954 && !TYPE_HAS_CONST_COPY_CTOR (type))
2955 *cant_have_const_ctor = 1;
2957 if (TYPE_HAS_COPY_ASSIGN (type)
2958 && !TYPE_HAS_CONST_COPY_ASSIGN (type))
2959 *no_const_asn_ref = 1;
2961 if (DECL_INITIAL (field) != NULL_TREE)
2963 /* `build_class_init_list' does not recognize
2965 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2966 error ("multiple fields in union %qT initialized", t);
2967 *any_default_members = 1;
2971 /* Check the data members (both static and non-static), class-scoped
2972 typedefs, etc., appearing in the declaration of T. Issue
2973 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2974 declaration order) of access declarations; each TREE_VALUE in this
2975 list is a USING_DECL.
2977 In addition, set the following flags:
2980 The class is empty, i.e., contains no non-static data members.
2982 CANT_HAVE_CONST_CTOR_P
2983 This class cannot have an implicitly generated copy constructor
2984 taking a const reference.
2986 CANT_HAVE_CONST_ASN_REF
2987 This class cannot have an implicitly generated assignment
2988 operator taking a const reference.
2990 All of these flags should be initialized before calling this
2993 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2994 fields can be added by adding to this chain. */
2997 check_field_decls (tree t, tree *access_decls,
2998 int *cant_have_const_ctor_p,
2999 int *no_const_asn_ref_p)
3004 int any_default_members;
3006 int field_access = -1;
3008 /* Assume there are no access declarations. */
3009 *access_decls = NULL_TREE;
3010 /* Assume this class has no pointer members. */
3011 has_pointers = false;
3012 /* Assume none of the members of this class have default
3014 any_default_members = 0;
3016 for (field = &TYPE_FIELDS (t); *field; field = next)
3019 tree type = TREE_TYPE (x);
3020 int this_field_access;
3022 next = &DECL_CHAIN (x);
3024 if (TREE_CODE (x) == USING_DECL)
3026 /* Prune the access declaration from the list of fields. */
3027 *field = DECL_CHAIN (x);
3029 /* Save the access declarations for our caller. */
3030 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
3032 /* Since we've reset *FIELD there's no reason to skip to the
3038 if (TREE_CODE (x) == TYPE_DECL
3039 || TREE_CODE (x) == TEMPLATE_DECL)
3042 /* If we've gotten this far, it's a data member, possibly static,
3043 or an enumerator. */
3044 DECL_CONTEXT (x) = t;
3046 /* When this goes into scope, it will be a non-local reference. */
3047 DECL_NONLOCAL (x) = 1;
3049 if (TREE_CODE (t) == UNION_TYPE)
3053 If a union contains a static data member, or a member of
3054 reference type, the program is ill-formed. */
3055 if (TREE_CODE (x) == VAR_DECL)
3057 error ("%q+D may not be static because it is a member of a union", x);
3060 if (TREE_CODE (type) == REFERENCE_TYPE)
3062 error ("%q+D may not have reference type %qT because"
3063 " it is a member of a union",
3069 /* Perform error checking that did not get done in
3071 if (TREE_CODE (type) == FUNCTION_TYPE)
3073 error ("field %q+D invalidly declared function type", x);
3074 type = build_pointer_type (type);
3075 TREE_TYPE (x) = type;
3077 else if (TREE_CODE (type) == METHOD_TYPE)
3079 error ("field %q+D invalidly declared method type", x);
3080 type = build_pointer_type (type);
3081 TREE_TYPE (x) = type;
3084 if (type == error_mark_node)
3087 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
3090 /* Now it can only be a FIELD_DECL. */
3092 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3093 CLASSTYPE_NON_AGGREGATE (t) = 1;
3095 /* If at least one non-static data member is non-literal, the whole
3096 class becomes non-literal. */
3097 if (!literal_type_p (type))
3098 CLASSTYPE_LITERAL_P (t) = false;
3100 /* A standard-layout class is a class that:
3102 has the same access control (Clause 11) for all non-static data members,
3104 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3105 if (field_access == -1)
3106 field_access = this_field_access;
3107 else if (this_field_access != field_access)
3108 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3110 /* If this is of reference type, check if it needs an init. */
3111 if (TREE_CODE (type) == REFERENCE_TYPE)
3113 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3114 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3115 if (DECL_INITIAL (x) == NULL_TREE)
3116 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3118 /* ARM $12.6.2: [A member initializer list] (or, for an
3119 aggregate, initialization by a brace-enclosed list) is the
3120 only way to initialize nonstatic const and reference
3122 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3123 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3126 type = strip_array_types (type);
3128 if (TYPE_PACKED (t))
3130 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3134 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3138 else if (DECL_C_BIT_FIELD (x)
3139 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3140 DECL_PACKED (x) = 1;
3143 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3144 /* We don't treat zero-width bitfields as making a class
3149 /* The class is non-empty. */
3150 CLASSTYPE_EMPTY_P (t) = 0;
3151 /* The class is not even nearly empty. */
3152 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3153 /* If one of the data members contains an empty class,
3155 if (CLASS_TYPE_P (type)
3156 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3157 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3160 /* This is used by -Weffc++ (see below). Warn only for pointers
3161 to members which might hold dynamic memory. So do not warn
3162 for pointers to functions or pointers to members. */
3163 if (TYPE_PTR_P (type)
3164 && !TYPE_PTRFN_P (type)
3165 && !TYPE_PTR_TO_MEMBER_P (type))
3166 has_pointers = true;
3168 if (CLASS_TYPE_P (type))
3170 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3171 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3172 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3173 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3176 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3177 CLASSTYPE_HAS_MUTABLE (t) = 1;
3179 if (! layout_pod_type_p (type))
3180 /* DR 148 now allows pointers to members (which are POD themselves),
3181 to be allowed in POD structs. */
3182 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3184 if (!std_layout_type_p (type))
3185 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3187 if (! zero_init_p (type))
3188 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3190 /* We set DECL_C_BIT_FIELD in grokbitfield.
3191 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3192 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3193 check_field_decl (x, t,
3194 cant_have_const_ctor_p,
3196 &any_default_members);
3198 /* If any field is const, the structure type is pseudo-const. */
3199 if (CP_TYPE_CONST_P (type))
3201 C_TYPE_FIELDS_READONLY (t) = 1;
3202 if (DECL_INITIAL (x) == NULL_TREE)
3203 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3205 /* ARM $12.6.2: [A member initializer list] (or, for an
3206 aggregate, initialization by a brace-enclosed list) is the
3207 only way to initialize nonstatic const and reference
3209 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3210 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3212 /* A field that is pseudo-const makes the structure likewise. */
3213 else if (CLASS_TYPE_P (type))
3215 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3216 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3217 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3218 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3221 /* Core issue 80: A nonstatic data member is required to have a
3222 different name from the class iff the class has a
3223 user-declared constructor. */
3224 if (constructor_name_p (DECL_NAME (x), t)
3225 && TYPE_HAS_USER_CONSTRUCTOR (t))
3226 permerror (input_location, "field %q+#D with same name as class", x);
3229 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3230 it should also define a copy constructor and an assignment operator to
3231 implement the correct copy semantic (deep vs shallow, etc.). As it is
3232 not feasible to check whether the constructors do allocate dynamic memory
3233 and store it within members, we approximate the warning like this:
3235 -- Warn only if there are members which are pointers
3236 -- Warn only if there is a non-trivial constructor (otherwise,
3237 there cannot be memory allocated).
3238 -- Warn only if there is a non-trivial destructor. We assume that the
3239 user at least implemented the cleanup correctly, and a destructor
3240 is needed to free dynamic memory.
3242 This seems enough for practical purposes. */
3245 && TYPE_HAS_USER_CONSTRUCTOR (t)
3246 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3247 && !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
3249 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3251 if (! TYPE_HAS_COPY_CTOR (t))
3253 warning (OPT_Weffc__,
3254 " but does not override %<%T(const %T&)%>", t, t);
3255 if (!TYPE_HAS_COPY_ASSIGN (t))
3256 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3258 else if (! TYPE_HAS_COPY_ASSIGN (t))
3259 warning (OPT_Weffc__,
3260 " but does not override %<operator=(const %T&)%>", t);
3263 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3265 TYPE_PACKED (t) = 0;
3267 /* Check anonymous struct/anonymous union fields. */
3268 finish_struct_anon (t);
3270 /* We've built up the list of access declarations in reverse order.
3272 *access_decls = nreverse (*access_decls);
3275 /* If TYPE is an empty class type, records its OFFSET in the table of
3279 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3283 if (!is_empty_class (type))
3286 /* Record the location of this empty object in OFFSETS. */
3287 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3289 n = splay_tree_insert (offsets,
3290 (splay_tree_key) offset,
3291 (splay_tree_value) NULL_TREE);
3292 n->value = ((splay_tree_value)
3293 tree_cons (NULL_TREE,
3300 /* Returns nonzero if TYPE is an empty class type and there is
3301 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3304 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3309 if (!is_empty_class (type))
3312 /* Record the location of this empty object in OFFSETS. */
3313 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3317 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3318 if (same_type_p (TREE_VALUE (t), type))
3324 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3325 F for every subobject, passing it the type, offset, and table of
3326 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3329 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3330 than MAX_OFFSET will not be walked.
3332 If F returns a nonzero value, the traversal ceases, and that value
3333 is returned. Otherwise, returns zero. */
3336 walk_subobject_offsets (tree type,
3337 subobject_offset_fn f,
3344 tree type_binfo = NULL_TREE;
3346 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3348 if (max_offset && INT_CST_LT (max_offset, offset))
3351 if (type == error_mark_node)
3356 if (abi_version_at_least (2))
3358 type = BINFO_TYPE (type);
3361 if (CLASS_TYPE_P (type))
3367 /* Avoid recursing into objects that are not interesting. */
3368 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3371 /* Record the location of TYPE. */
3372 r = (*f) (type, offset, offsets);
3376 /* Iterate through the direct base classes of TYPE. */
3378 type_binfo = TYPE_BINFO (type);
3379 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3383 if (abi_version_at_least (2)
3384 && BINFO_VIRTUAL_P (binfo))
3388 && BINFO_VIRTUAL_P (binfo)
3389 && !BINFO_PRIMARY_P (binfo))
3392 if (!abi_version_at_least (2))
3393 binfo_offset = size_binop (PLUS_EXPR,
3395 BINFO_OFFSET (binfo));
3399 /* We cannot rely on BINFO_OFFSET being set for the base
3400 class yet, but the offsets for direct non-virtual
3401 bases can be calculated by going back to the TYPE. */
3402 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3403 binfo_offset = size_binop (PLUS_EXPR,
3405 BINFO_OFFSET (orig_binfo));
3408 r = walk_subobject_offsets (binfo,
3413 (abi_version_at_least (2)
3414 ? /*vbases_p=*/0 : vbases_p));
3419 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3422 VEC(tree,gc) *vbases;
3424 /* Iterate through the virtual base classes of TYPE. In G++
3425 3.2, we included virtual bases in the direct base class
3426 loop above, which results in incorrect results; the
3427 correct offsets for virtual bases are only known when
3428 working with the most derived type. */
3430 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3431 VEC_iterate (tree, vbases, ix, binfo); ix++)
3433 r = walk_subobject_offsets (binfo,
3435 size_binop (PLUS_EXPR,
3437 BINFO_OFFSET (binfo)),
3446 /* We still have to walk the primary base, if it is
3447 virtual. (If it is non-virtual, then it was walked
3449 tree vbase = get_primary_binfo (type_binfo);
3451 if (vbase && BINFO_VIRTUAL_P (vbase)
3452 && BINFO_PRIMARY_P (vbase)
3453 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3455 r = (walk_subobject_offsets
3457 offsets, max_offset, /*vbases_p=*/0));
3464 /* Iterate through the fields of TYPE. */
3465 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
3466 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3470 if (abi_version_at_least (2))
3471 field_offset = byte_position (field);
3473 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3474 field_offset = DECL_FIELD_OFFSET (field);
3476 r = walk_subobject_offsets (TREE_TYPE (field),
3478 size_binop (PLUS_EXPR,
3488 else if (TREE_CODE (type) == ARRAY_TYPE)
3490 tree element_type = strip_array_types (type);
3491 tree domain = TYPE_DOMAIN (type);
3494 /* Avoid recursing into objects that are not interesting. */
3495 if (!CLASS_TYPE_P (element_type)
3496 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3499 /* Step through each of the elements in the array. */
3500 for (index = size_zero_node;
3501 /* G++ 3.2 had an off-by-one error here. */
3502 (abi_version_at_least (2)
3503 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3504 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3505 index = size_binop (PLUS_EXPR, index, size_one_node))
3507 r = walk_subobject_offsets (TREE_TYPE (type),
3515 offset = size_binop (PLUS_EXPR, offset,
3516 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3517 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3518 there's no point in iterating through the remaining
3519 elements of the array. */
3520 if (max_offset && INT_CST_LT (max_offset, offset))
3528 /* Record all of the empty subobjects of TYPE (either a type or a
3529 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3530 is being placed at OFFSET; otherwise, it is a base class that is
3531 being placed at OFFSET. */
3534 record_subobject_offsets (tree type,
3537 bool is_data_member)
3540 /* If recording subobjects for a non-static data member or a
3541 non-empty base class , we do not need to record offsets beyond
3542 the size of the biggest empty class. Additional data members
3543 will go at the end of the class. Additional base classes will go
3544 either at offset zero (if empty, in which case they cannot
3545 overlap with offsets past the size of the biggest empty class) or
3546 at the end of the class.
3548 However, if we are placing an empty base class, then we must record
3549 all offsets, as either the empty class is at offset zero (where
3550 other empty classes might later be placed) or at the end of the
3551 class (where other objects might then be placed, so other empty
3552 subobjects might later overlap). */
3554 || !is_empty_class (BINFO_TYPE (type)))
3555 max_offset = sizeof_biggest_empty_class;
3557 max_offset = NULL_TREE;
3558 walk_subobject_offsets (type, record_subobject_offset, offset,
3559 offsets, max_offset, is_data_member);
3562 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3563 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3564 virtual bases of TYPE are examined. */
3567 layout_conflict_p (tree type,
3572 splay_tree_node max_node;
3574 /* Get the node in OFFSETS that indicates the maximum offset where
3575 an empty subobject is located. */
3576 max_node = splay_tree_max (offsets);
3577 /* If there aren't any empty subobjects, then there's no point in
3578 performing this check. */
3582 return walk_subobject_offsets (type, check_subobject_offset, offset,
3583 offsets, (tree) (max_node->key),
3587 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3588 non-static data member of the type indicated by RLI. BINFO is the
3589 binfo corresponding to the base subobject, OFFSETS maps offsets to
3590 types already located at those offsets. This function determines
3591 the position of the DECL. */
3594 layout_nonempty_base_or_field (record_layout_info rli,
3599 tree offset = NULL_TREE;
3605 /* For the purposes of determining layout conflicts, we want to
3606 use the class type of BINFO; TREE_TYPE (DECL) will be the
3607 CLASSTYPE_AS_BASE version, which does not contain entries for
3608 zero-sized bases. */
3609 type = TREE_TYPE (binfo);
3614 type = TREE_TYPE (decl);
3618 /* Try to place the field. It may take more than one try if we have
3619 a hard time placing the field without putting two objects of the
3620 same type at the same address. */
3623 struct record_layout_info_s old_rli = *rli;
3625 /* Place this field. */
3626 place_field (rli, decl);
3627 offset = byte_position (decl);
3629 /* We have to check to see whether or not there is already
3630 something of the same type at the offset we're about to use.
3631 For example, consider:
3634 struct T : public S { int i; };
3635 struct U : public S, public T {};
3637 Here, we put S at offset zero in U. Then, we can't put T at
3638 offset zero -- its S component would be at the same address
3639 as the S we already allocated. So, we have to skip ahead.
3640 Since all data members, including those whose type is an
3641 empty class, have nonzero size, any overlap can happen only
3642 with a direct or indirect base-class -- it can't happen with
3644 /* In a union, overlap is permitted; all members are placed at
3646 if (TREE_CODE (rli->t) == UNION_TYPE)
3648 /* G++ 3.2 did not check for overlaps when placing a non-empty
3650 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3652 if (layout_conflict_p (field_p ? type : binfo, offset,
3655 /* Strip off the size allocated to this field. That puts us
3656 at the first place we could have put the field with
3657 proper alignment. */
3660 /* Bump up by the alignment required for the type. */
3662 = size_binop (PLUS_EXPR, rli->bitpos,
3664 ? CLASSTYPE_ALIGN (type)
3665 : TYPE_ALIGN (type)));
3666 normalize_rli (rli);
3669 /* There was no conflict. We're done laying out this field. */
3673 /* Now that we know where it will be placed, update its
3675 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3676 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3677 this point because their BINFO_OFFSET is copied from another
3678 hierarchy. Therefore, we may not need to add the entire
3680 propagate_binfo_offsets (binfo,
3681 size_diffop_loc (input_location,
3682 convert (ssizetype, offset),
3684 BINFO_OFFSET (binfo))));
3687 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3690 empty_base_at_nonzero_offset_p (tree type,
3692 splay_tree offsets ATTRIBUTE_UNUSED)
3694 return is_empty_class (type) && !integer_zerop (offset);
3697 /* Layout the empty base BINFO. EOC indicates the byte currently just
3698 past the end of the class, and should be correctly aligned for a
3699 class of the type indicated by BINFO; OFFSETS gives the offsets of
3700 the empty bases allocated so far. T is the most derived
3701 type. Return nonzero iff we added it at the end. */
3704 layout_empty_base (record_layout_info rli, tree binfo,
3705 tree eoc, splay_tree offsets)
3708 tree basetype = BINFO_TYPE (binfo);
3711 /* This routine should only be used for empty classes. */
3712 gcc_assert (is_empty_class (basetype));
3713 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3715 if (!integer_zerop (BINFO_OFFSET (binfo)))
3717 if (abi_version_at_least (2))
3718 propagate_binfo_offsets
3719 (binfo, size_diffop_loc (input_location,
3720 size_zero_node, BINFO_OFFSET (binfo)));
3723 "offset of empty base %qT may not be ABI-compliant and may"
3724 "change in a future version of GCC",
3725 BINFO_TYPE (binfo));
3728 /* This is an empty base class. We first try to put it at offset
3730 if (layout_conflict_p (binfo,
3731 BINFO_OFFSET (binfo),
3735 /* That didn't work. Now, we move forward from the next
3736 available spot in the class. */
3738 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3741 if (!layout_conflict_p (binfo,
3742 BINFO_OFFSET (binfo),
3745 /* We finally found a spot where there's no overlap. */
3748 /* There's overlap here, too. Bump along to the next spot. */
3749 propagate_binfo_offsets (binfo, alignment);
3753 if (CLASSTYPE_USER_ALIGN (basetype))
3755 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3757 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3758 TYPE_USER_ALIGN (rli->t) = 1;
3764 /* Layout the base given by BINFO in the class indicated by RLI.
3765 *BASE_ALIGN is a running maximum of the alignments of
3766 any base class. OFFSETS gives the location of empty base
3767 subobjects. T is the most derived type. Return nonzero if the new
3768 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3769 *NEXT_FIELD, unless BINFO is for an empty base class.
3771 Returns the location at which the next field should be inserted. */
3774 build_base_field (record_layout_info rli, tree binfo,
3775 splay_tree offsets, tree *next_field)
3778 tree basetype = BINFO_TYPE (binfo);
3780 if (!COMPLETE_TYPE_P (basetype))
3781 /* This error is now reported in xref_tag, thus giving better
3782 location information. */
3785 /* Place the base class. */
3786 if (!is_empty_class (basetype))
3790 /* The containing class is non-empty because it has a non-empty
3792 CLASSTYPE_EMPTY_P (t) = 0;
3794 /* Create the FIELD_DECL. */
3795 decl = build_decl (input_location,
3796 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3797 DECL_ARTIFICIAL (decl) = 1;
3798 DECL_IGNORED_P (decl) = 1;
3799 DECL_FIELD_CONTEXT (decl) = t;
3800 if (CLASSTYPE_AS_BASE (basetype))
3802 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3803 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3804 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3805 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3806 DECL_MODE (decl) = TYPE_MODE (basetype);
3807 DECL_FIELD_IS_BASE (decl) = 1;
3809 /* Try to place the field. It may take more than one try if we
3810 have a hard time placing the field without putting two
3811 objects of the same type at the same address. */
3812 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3813 /* Add the new FIELD_DECL to the list of fields for T. */
3814 DECL_CHAIN (decl) = *next_field;
3816 next_field = &DECL_CHAIN (decl);
3824 /* On some platforms (ARM), even empty classes will not be
3826 eoc = round_up_loc (input_location,
3827 rli_size_unit_so_far (rli),
3828 CLASSTYPE_ALIGN_UNIT (basetype));
3829 atend = layout_empty_base (rli, binfo, eoc, offsets);
3830 /* A nearly-empty class "has no proper base class that is empty,
3831 not morally virtual, and at an offset other than zero." */
3832 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3835 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3836 /* The check above (used in G++ 3.2) is insufficient because
3837 an empty class placed at offset zero might itself have an
3838 empty base at a nonzero offset. */
3839 else if (walk_subobject_offsets (basetype,
3840 empty_base_at_nonzero_offset_p,
3843 /*max_offset=*/NULL_TREE,
3846 if (abi_version_at_least (2))
3847 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3850 "class %qT will be considered nearly empty in a "
3851 "future version of GCC", t);
3855 /* We do not create a FIELD_DECL for empty base classes because
3856 it might overlap some other field. We want to be able to
3857 create CONSTRUCTORs for the class by iterating over the
3858 FIELD_DECLs, and the back end does not handle overlapping
3861 /* An empty virtual base causes a class to be non-empty
3862 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3863 here because that was already done when the virtual table
3864 pointer was created. */
3867 /* Record the offsets of BINFO and its base subobjects. */
3868 record_subobject_offsets (binfo,
3869 BINFO_OFFSET (binfo),
3871 /*is_data_member=*/false);
3876 /* Layout all of the non-virtual base classes. Record empty
3877 subobjects in OFFSETS. T is the most derived type. Return nonzero
3878 if the type cannot be nearly empty. The fields created
3879 corresponding to the base classes will be inserted at
3883 build_base_fields (record_layout_info rli,
3884 splay_tree offsets, tree *next_field)
3886 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3889 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3892 /* The primary base class is always allocated first. */
3893 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3894 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3895 offsets, next_field);
3897 /* Now allocate the rest of the bases. */
3898 for (i = 0; i < n_baseclasses; ++i)
3902 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3904 /* The primary base was already allocated above, so we don't
3905 need to allocate it again here. */
3906 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3909 /* Virtual bases are added at the end (a primary virtual base
3910 will have already been added). */
3911 if (BINFO_VIRTUAL_P (base_binfo))
3914 next_field = build_base_field (rli, base_binfo,
3915 offsets, next_field);
3919 /* Go through the TYPE_METHODS of T issuing any appropriate
3920 diagnostics, figuring out which methods override which other
3921 methods, and so forth. */
3924 check_methods (tree t)
3928 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
3930 check_for_override (x, t);
3931 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3932 error ("initializer specified for non-virtual method %q+D", x);
3933 /* The name of the field is the original field name
3934 Save this in auxiliary field for later overloading. */
3935 if (DECL_VINDEX (x))
3937 TYPE_POLYMORPHIC_P (t) = 1;
3938 if (DECL_PURE_VIRTUAL_P (x))
3939 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3941 /* All user-provided destructors are non-trivial.
3942 Constructors and assignment ops are handled in
3943 grok_special_member_properties. */
3944 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
3945 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3949 /* FN is a constructor or destructor. Clone the declaration to create
3950 a specialized in-charge or not-in-charge version, as indicated by
3954 build_clone (tree fn, tree name)
3959 /* Copy the function. */
3960 clone = copy_decl (fn);
3961 /* Reset the function name. */
3962 DECL_NAME (clone) = name;
3963 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3964 /* Remember where this function came from. */
3965 DECL_ABSTRACT_ORIGIN (clone) = fn;
3966 /* Make it easy to find the CLONE given the FN. */
3967 DECL_CHAIN (clone) = DECL_CHAIN (fn);
3968 DECL_CHAIN (fn) = clone;
3970 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3971 if (TREE_CODE (clone) == TEMPLATE_DECL)
3973 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3974 DECL_TEMPLATE_RESULT (clone) = result;
3975 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3976 DECL_TI_TEMPLATE (result) = clone;
3977 TREE_TYPE (clone) = TREE_TYPE (result);
3981 DECL_CLONED_FUNCTION (clone) = fn;
3982 /* There's no pending inline data for this function. */
3983 DECL_PENDING_INLINE_INFO (clone) = NULL;
3984 DECL_PENDING_INLINE_P (clone) = 0;
3986 /* The base-class destructor is not virtual. */
3987 if (name == base_dtor_identifier)
3989 DECL_VIRTUAL_P (clone) = 0;
3990 if (TREE_CODE (clone) != TEMPLATE_DECL)
3991 DECL_VINDEX (clone) = NULL_TREE;
3994 /* If there was an in-charge parameter, drop it from the function
3996 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4002 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4003 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4004 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
4005 /* Skip the `this' parameter. */
4006 parmtypes = TREE_CHAIN (parmtypes);
4007 /* Skip the in-charge parameter. */
4008 parmtypes = TREE_CHAIN (parmtypes);
4009 /* And the VTT parm, in a complete [cd]tor. */
4010 if (DECL_HAS_VTT_PARM_P (fn)
4011 && ! DECL_NEEDS_VTT_PARM_P (clone))
4012 parmtypes = TREE_CHAIN (parmtypes);
4013 /* If this is subobject constructor or destructor, add the vtt
4016 = build_method_type_directly (basetype,
4017 TREE_TYPE (TREE_TYPE (clone)),
4020 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
4023 = cp_build_type_attribute_variant (TREE_TYPE (clone),
4024 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
4027 /* Copy the function parameters. */
4028 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
4029 /* Remove the in-charge parameter. */
4030 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4032 DECL_CHAIN (DECL_ARGUMENTS (clone))
4033 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4034 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
4036 /* And the VTT parm, in a complete [cd]tor. */
4037 if (DECL_HAS_VTT_PARM_P (fn))
4039 if (DECL_NEEDS_VTT_PARM_P (clone))
4040 DECL_HAS_VTT_PARM_P (clone) = 1;
4043 DECL_CHAIN (DECL_ARGUMENTS (clone))
4044 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4045 DECL_HAS_VTT_PARM_P (clone) = 0;
4049 for (parms = DECL_ARGUMENTS (clone); parms; parms = DECL_CHAIN (parms))
4051 DECL_CONTEXT (parms) = clone;
4052 cxx_dup_lang_specific_decl (parms);
4055 /* Create the RTL for this function. */
4056 SET_DECL_RTL (clone, NULL);
4057 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
4060 note_decl_for_pch (clone);
4065 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4066 not invoke this function directly.
4068 For a non-thunk function, returns the address of the slot for storing
4069 the function it is a clone of. Otherwise returns NULL_TREE.
4071 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4072 cloned_function is unset. This is to support the separate
4073 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4074 on a template makes sense, but not the former. */
4077 decl_cloned_function_p (const_tree decl, bool just_testing)
4081 decl = STRIP_TEMPLATE (decl);
4083 if (TREE_CODE (decl) != FUNCTION_DECL
4084 || !DECL_LANG_SPECIFIC (decl)
4085 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
4087 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4089 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
4095 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
4096 if (just_testing && *ptr == NULL_TREE)
4102 /* Produce declarations for all appropriate clones of FN. If
4103 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4104 CLASTYPE_METHOD_VEC as well. */
4107 clone_function_decl (tree fn, int update_method_vec_p)
4111 /* Avoid inappropriate cloning. */
4113 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (fn)))
4116 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4118 /* For each constructor, we need two variants: an in-charge version
4119 and a not-in-charge version. */
4120 clone = build_clone (fn, complete_ctor_identifier);
4121 if (update_method_vec_p)
4122 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4123 clone = build_clone (fn, base_ctor_identifier);
4124 if (update_method_vec_p)
4125 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4129 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4131 /* For each destructor, we need three variants: an in-charge
4132 version, a not-in-charge version, and an in-charge deleting
4133 version. We clone the deleting version first because that
4134 means it will go second on the TYPE_METHODS list -- and that
4135 corresponds to the correct layout order in the virtual
4138 For a non-virtual destructor, we do not build a deleting
4140 if (DECL_VIRTUAL_P (fn))
4142 clone = build_clone (fn, deleting_dtor_identifier);
4143 if (update_method_vec_p)
4144 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4146 clone = build_clone (fn, complete_dtor_identifier);
4147 if (update_method_vec_p)
4148 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4149 clone = build_clone (fn, base_dtor_identifier);
4150 if (update_method_vec_p)
4151 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4154 /* Note that this is an abstract function that is never emitted. */
4155 DECL_ABSTRACT (fn) = 1;
4158 /* DECL is an in charge constructor, which is being defined. This will
4159 have had an in class declaration, from whence clones were
4160 declared. An out-of-class definition can specify additional default
4161 arguments. As it is the clones that are involved in overload
4162 resolution, we must propagate the information from the DECL to its
4166 adjust_clone_args (tree decl)
4170 for (clone = DECL_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4171 clone = DECL_CHAIN (clone))
4173 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4174 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4175 tree decl_parms, clone_parms;
4177 clone_parms = orig_clone_parms;
4179 /* Skip the 'this' parameter. */
4180 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4181 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4183 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4184 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4185 if (DECL_HAS_VTT_PARM_P (decl))
4186 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4188 clone_parms = orig_clone_parms;
4189 if (DECL_HAS_VTT_PARM_P (clone))
4190 clone_parms = TREE_CHAIN (clone_parms);
4192 for (decl_parms = orig_decl_parms; decl_parms;
4193 decl_parms = TREE_CHAIN (decl_parms),
4194 clone_parms = TREE_CHAIN (clone_parms))
4196 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4197 TREE_TYPE (clone_parms)));
4199 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4201 /* A default parameter has been added. Adjust the
4202 clone's parameters. */
4203 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4204 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4205 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4208 clone_parms = orig_decl_parms;
4210 if (DECL_HAS_VTT_PARM_P (clone))
4212 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4213 TREE_VALUE (orig_clone_parms),
4215 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4217 type = build_method_type_directly (basetype,
4218 TREE_TYPE (TREE_TYPE (clone)),
4221 type = build_exception_variant (type, exceptions);
4223 type = cp_build_type_attribute_variant (type, attrs);
4224 TREE_TYPE (clone) = type;
4226 clone_parms = NULL_TREE;
4230 gcc_assert (!clone_parms);
4234 /* For each of the constructors and destructors in T, create an
4235 in-charge and not-in-charge variant. */
4238 clone_constructors_and_destructors (tree t)
4242 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4244 if (!CLASSTYPE_METHOD_VEC (t))
4247 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4248 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4249 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4250 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4253 /* Returns true iff class T has a user-defined constructor other than
4254 the default constructor. */
4257 type_has_user_nondefault_constructor (tree t)
4261 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4264 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4266 tree fn = OVL_CURRENT (fns);
4267 if (!DECL_ARTIFICIAL (fn)
4268 && (TREE_CODE (fn) == TEMPLATE_DECL
4269 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4277 /* Returns the defaulted constructor if T has one. Otherwise, returns
4281 in_class_defaulted_default_constructor (tree t)
4285 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4288 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4290 tree fn = OVL_CURRENT (fns);
4292 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4294 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4295 while (args && TREE_PURPOSE (args))
4296 args = TREE_CHAIN (args);
4297 if (!args || args == void_list_node)
4305 /* Returns true iff FN is a user-provided function, i.e. user-declared
4306 and not defaulted at its first declaration; or explicit, private,
4307 protected, or non-const. */
4310 user_provided_p (tree fn)
4312 if (TREE_CODE (fn) == TEMPLATE_DECL)
4315 return (!DECL_ARTIFICIAL (fn)
4316 && !DECL_DEFAULTED_IN_CLASS_P (fn));
4319 /* Returns true iff class T has a user-provided constructor. */
4322 type_has_user_provided_constructor (tree t)
4326 if (!CLASS_TYPE_P (t))
4329 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4332 /* This can happen in error cases; avoid crashing. */
4333 if (!CLASSTYPE_METHOD_VEC (t))
4336 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4337 if (user_provided_p (OVL_CURRENT (fns)))
4343 /* Returns true iff class T has a user-provided default constructor. */
4346 type_has_user_provided_default_constructor (tree t)
4350 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4353 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4355 tree fn = OVL_CURRENT (fns);
4356 if (TREE_CODE (fn) == FUNCTION_DECL
4357 && user_provided_p (fn)
4358 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)))
4365 /* Returns true iff for class T, a synthesized default constructor
4366 would be constexpr. */
4369 synthesized_default_constructor_is_constexpr (tree t)
4371 /* A defaulted default constructor is constexpr
4372 if there is nothing to initialize. */
4373 /* FIXME adjust for non-static data member initializers. */
4374 return is_really_empty_class (t);
4377 /* Returns true iff class T has a constexpr default constructor. */
4380 type_has_constexpr_default_constructor (tree t)
4384 if (!CLASS_TYPE_P (t))
4386 /* The caller should have stripped an enclosing array. */
4387 gcc_assert (TREE_CODE (t) != ARRAY_TYPE);
4390 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t))
4391 return synthesized_default_constructor_is_constexpr (t);
4392 fns = locate_ctor (t);
4393 return (fns && DECL_DECLARED_CONSTEXPR_P (fns));
4396 /* Returns true iff class TYPE has a virtual destructor. */
4399 type_has_virtual_destructor (tree type)
4403 if (!CLASS_TYPE_P (type))
4406 gcc_assert (COMPLETE_TYPE_P (type));
4407 dtor = CLASSTYPE_DESTRUCTORS (type);
4408 return (dtor && DECL_VIRTUAL_P (dtor));
4411 /* Returns true iff class T has a move constructor. */
4414 type_has_move_constructor (tree t)
4418 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4420 gcc_assert (COMPLETE_TYPE_P (t));
4421 lazily_declare_fn (sfk_move_constructor, t);
4424 if (!CLASSTYPE_METHOD_VEC (t))
4427 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4428 if (move_fn_p (OVL_CURRENT (fns)))
4434 /* Returns true iff class T has a move assignment operator. */
4437 type_has_move_assign (tree t)
4441 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4443 gcc_assert (COMPLETE_TYPE_P (t));
4444 lazily_declare_fn (sfk_move_assignment, t);
4447 for (fns = lookup_fnfields_slot (t, ansi_assopname (NOP_EXPR));
4448 fns; fns = OVL_NEXT (fns))
4449 if (move_fn_p (OVL_CURRENT (fns)))
4455 /* Nonzero if we need to build up a constructor call when initializing an
4456 object of this class, either because it has a user-provided constructor
4457 or because it doesn't have a default constructor (so we need to give an
4458 error if no initializer is provided). Use TYPE_NEEDS_CONSTRUCTING when
4459 what you care about is whether or not an object can be produced by a
4460 constructor (e.g. so we don't set TREE_READONLY on const variables of
4461 such type); use this function when what you care about is whether or not
4462 to try to call a constructor to create an object. The latter case is
4463 the former plus some cases of constructors that cannot be called. */
4466 type_build_ctor_call (tree t)
4469 if (TYPE_NEEDS_CONSTRUCTING (t))
4471 inner = strip_array_types (t);
4472 return (CLASS_TYPE_P (inner) && !TYPE_HAS_DEFAULT_CONSTRUCTOR (inner)
4473 && !ANON_AGGR_TYPE_P (inner));
4476 /* Remove all zero-width bit-fields from T. */
4479 remove_zero_width_bit_fields (tree t)
4483 fieldsp = &TYPE_FIELDS (t);
4486 if (TREE_CODE (*fieldsp) == FIELD_DECL
4487 && DECL_C_BIT_FIELD (*fieldsp)
4488 /* We should not be confused by the fact that grokbitfield
4489 temporarily sets the width of the bit field into
4490 DECL_INITIAL (*fieldsp).
4491 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4493 && integer_zerop (DECL_SIZE (*fieldsp)))
4494 *fieldsp = DECL_CHAIN (*fieldsp);
4496 fieldsp = &DECL_CHAIN (*fieldsp);
4500 /* Returns TRUE iff we need a cookie when dynamically allocating an
4501 array whose elements have the indicated class TYPE. */
4504 type_requires_array_cookie (tree type)
4507 bool has_two_argument_delete_p = false;
4509 gcc_assert (CLASS_TYPE_P (type));
4511 /* If there's a non-trivial destructor, we need a cookie. In order
4512 to iterate through the array calling the destructor for each
4513 element, we'll have to know how many elements there are. */
4514 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4517 /* If the usual deallocation function is a two-argument whose second
4518 argument is of type `size_t', then we have to pass the size of
4519 the array to the deallocation function, so we will need to store
4521 fns = lookup_fnfields (TYPE_BINFO (type),
4522 ansi_opname (VEC_DELETE_EXPR),
4524 /* If there are no `operator []' members, or the lookup is
4525 ambiguous, then we don't need a cookie. */
4526 if (!fns || fns == error_mark_node)
4528 /* Loop through all of the functions. */
4529 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4534 /* Select the current function. */
4535 fn = OVL_CURRENT (fns);
4536 /* See if this function is a one-argument delete function. If
4537 it is, then it will be the usual deallocation function. */
4538 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4539 if (second_parm == void_list_node)
4541 /* Do not consider this function if its second argument is an
4545 /* Otherwise, if we have a two-argument function and the second
4546 argument is `size_t', it will be the usual deallocation
4547 function -- unless there is one-argument function, too. */
4548 if (TREE_CHAIN (second_parm) == void_list_node
4549 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4550 has_two_argument_delete_p = true;
4553 return has_two_argument_delete_p;
4556 /* Finish computing the `literal type' property of class type T.
4558 At this point, we have already processed base classes and
4559 non-static data members. We need to check whether the copy
4560 constructor is trivial, the destructor is trivial, and there
4561 is a trivial default constructor or at least one constexpr
4562 constructor other than the copy constructor. */
4565 finalize_literal_type_property (tree t)
4569 if (cxx_dialect < cxx0x
4570 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
4571 CLASSTYPE_LITERAL_P (t) = false;
4572 else if (CLASSTYPE_LITERAL_P (t) && !TYPE_HAS_TRIVIAL_DFLT (t)
4573 && CLASSTYPE_NON_AGGREGATE (t)
4574 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4575 CLASSTYPE_LITERAL_P (t) = false;
4577 if (!CLASSTYPE_LITERAL_P (t))
4578 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4579 if (DECL_DECLARED_CONSTEXPR_P (fn)
4580 && TREE_CODE (fn) != TEMPLATE_DECL
4581 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
4582 && !DECL_CONSTRUCTOR_P (fn))
4584 DECL_DECLARED_CONSTEXPR_P (fn) = false;
4585 if (!DECL_TEMPLATE_INFO (fn))
4587 error ("enclosing class of constexpr non-static member "
4588 "function %q+#D is not a literal type", fn);
4589 explain_non_literal_class (t);
4594 /* T is a non-literal type used in a context which requires a constant
4595 expression. Explain why it isn't literal. */
4598 explain_non_literal_class (tree t)
4600 static struct pointer_set_t *diagnosed;
4602 if (!CLASS_TYPE_P (t))
4604 t = TYPE_MAIN_VARIANT (t);
4606 if (diagnosed == NULL)
4607 diagnosed = pointer_set_create ();
4608 if (pointer_set_insert (diagnosed, t) != 0)
4609 /* Already explained. */
4612 inform (0, "%q+T is not literal because:", t);
4613 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
4614 inform (0, " %q+T has a non-trivial destructor", t);
4615 else if (CLASSTYPE_NON_AGGREGATE (t)
4616 && !TYPE_HAS_TRIVIAL_DFLT (t)
4617 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4618 inform (0, " %q+T is not an aggregate, does not have a trivial "
4619 "default constructor, and has no constexpr constructor that "
4620 "is not a copy or move constructor", t);
4623 tree binfo, base_binfo, field; int i;
4624 for (binfo = TYPE_BINFO (t), i = 0;
4625 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
4627 tree basetype = TREE_TYPE (base_binfo);
4628 if (!CLASSTYPE_LITERAL_P (basetype))
4630 inform (0, " base class %qT of %q+T is non-literal",
4632 explain_non_literal_class (basetype);
4636 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4639 if (TREE_CODE (field) != FIELD_DECL)
4641 ftype = TREE_TYPE (field);
4642 if (!literal_type_p (ftype))
4644 inform (0, " non-static data member %q+D has "
4645 "non-literal type", field);
4646 if (CLASS_TYPE_P (ftype))
4647 explain_non_literal_class (ftype);
4653 /* Check the validity of the bases and members declared in T. Add any
4654 implicitly-generated functions (like copy-constructors and
4655 assignment operators). Compute various flag bits (like
4656 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4657 level: i.e., independently of the ABI in use. */
4660 check_bases_and_members (tree t)
4662 /* Nonzero if the implicitly generated copy constructor should take
4663 a non-const reference argument. */
4664 int cant_have_const_ctor;
4665 /* Nonzero if the implicitly generated assignment operator
4666 should take a non-const reference argument. */
4667 int no_const_asn_ref;
4669 bool saved_complex_asn_ref;
4670 bool saved_nontrivial_dtor;
4673 /* By default, we use const reference arguments and generate default
4675 cant_have_const_ctor = 0;
4676 no_const_asn_ref = 0;
4678 /* Check all the base-classes. */
4679 check_bases (t, &cant_have_const_ctor,
4682 /* Check all the method declarations. */
4685 /* Save the initial values of these flags which only indicate whether
4686 or not the class has user-provided functions. As we analyze the
4687 bases and members we can set these flags for other reasons. */
4688 saved_complex_asn_ref = TYPE_HAS_COMPLEX_COPY_ASSIGN (t);
4689 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4691 /* Check all the data member declarations. We cannot call
4692 check_field_decls until we have called check_bases check_methods,
4693 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4694 being set appropriately. */
4695 check_field_decls (t, &access_decls,
4696 &cant_have_const_ctor,
4699 /* A nearly-empty class has to be vptr-containing; a nearly empty
4700 class contains just a vptr. */
4701 if (!TYPE_CONTAINS_VPTR_P (t))
4702 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4704 /* Do some bookkeeping that will guide the generation of implicitly
4705 declared member functions. */
4706 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4707 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4708 /* We need to call a constructor for this class if it has a
4709 user-provided constructor, or if the default constructor is going
4710 to initialize the vptr. (This is not an if-and-only-if;
4711 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4712 themselves need constructing.) */
4713 TYPE_NEEDS_CONSTRUCTING (t)
4714 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4717 An aggregate is an array or a class with no user-provided
4718 constructors ... and no virtual functions.
4720 Again, other conditions for being an aggregate are checked
4722 CLASSTYPE_NON_AGGREGATE (t)
4723 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4724 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4725 retain the old definition internally for ABI reasons. */
4726 CLASSTYPE_NON_LAYOUT_POD_P (t)
4727 |= (CLASSTYPE_NON_AGGREGATE (t)
4728 || saved_nontrivial_dtor || saved_complex_asn_ref);
4729 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
4730 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4731 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4732 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4734 /* If the class has no user-declared constructor, but does have
4735 non-static const or reference data members that can never be
4736 initialized, issue a warning. */
4737 if (warn_uninitialized
4738 /* Classes with user-declared constructors are presumed to
4739 initialize these members. */
4740 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4741 /* Aggregates can be initialized with brace-enclosed
4743 && CLASSTYPE_NON_AGGREGATE (t))
4747 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
4751 if (TREE_CODE (field) != FIELD_DECL)
4754 type = TREE_TYPE (field);
4755 if (TREE_CODE (type) == REFERENCE_TYPE)
4756 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4757 "in class without a constructor", field);
4758 else if (CP_TYPE_CONST_P (type)
4759 && (!CLASS_TYPE_P (type)
4760 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4761 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4762 "in class without a constructor", field);
4766 /* Synthesize any needed methods. */
4767 add_implicitly_declared_members (t,
4768 cant_have_const_ctor,
4771 /* Check defaulted declarations here so we have cant_have_const_ctor
4772 and don't need to worry about clones. */
4773 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4774 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4776 int copy = copy_fn_p (fn);
4780 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
4781 : !no_const_asn_ref);
4782 bool fn_const_p = (copy == 2);
4784 if (fn_const_p && !imp_const_p)
4785 /* If the function is defaulted outside the class, we just
4786 give the synthesis error. */
4787 error ("%q+D declared to take const reference, but implicit "
4788 "declaration would take non-const", fn);
4789 else if (imp_const_p && !fn_const_p)
4790 error ("%q+D declared to take non-const reference cannot be "
4791 "defaulted in the class body", fn);
4793 defaulted_late_check (fn);
4796 if (LAMBDA_TYPE_P (t))
4798 /* "The closure type associated with a lambda-expression has a deleted
4799 default constructor and a deleted copy assignment operator." */
4800 TYPE_NEEDS_CONSTRUCTING (t) = 1;
4801 TYPE_HAS_COMPLEX_DFLT (t) = 1;
4802 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
4803 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 0;
4805 /* "This class type is not an aggregate." */
4806 CLASSTYPE_NON_AGGREGATE (t) = 1;
4809 /* Compute the 'literal type' property before we
4810 do anything with non-static member functions. */
4811 finalize_literal_type_property (t);
4813 /* Create the in-charge and not-in-charge variants of constructors
4815 clone_constructors_and_destructors (t);
4817 /* Process the using-declarations. */
4818 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4819 handle_using_decl (TREE_VALUE (access_decls), t);
4821 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4822 finish_struct_methods (t);
4824 /* Figure out whether or not we will need a cookie when dynamically
4825 allocating an array of this type. */
4826 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4827 = type_requires_array_cookie (t);
4830 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4831 accordingly. If a new vfield was created (because T doesn't have a
4832 primary base class), then the newly created field is returned. It
4833 is not added to the TYPE_FIELDS list; it is the caller's
4834 responsibility to do that. Accumulate declared virtual functions
4838 create_vtable_ptr (tree t, tree* virtuals_p)
4842 /* Collect the virtual functions declared in T. */
4843 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4844 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4845 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4847 tree new_virtual = make_node (TREE_LIST);
4849 BV_FN (new_virtual) = fn;
4850 BV_DELTA (new_virtual) = integer_zero_node;
4851 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4853 TREE_CHAIN (new_virtual) = *virtuals_p;
4854 *virtuals_p = new_virtual;
4857 /* If we couldn't find an appropriate base class, create a new field
4858 here. Even if there weren't any new virtual functions, we might need a
4859 new virtual function table if we're supposed to include vptrs in
4860 all classes that need them. */
4861 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4863 /* We build this decl with vtbl_ptr_type_node, which is a
4864 `vtable_entry_type*'. It might seem more precise to use
4865 `vtable_entry_type (*)[N]' where N is the number of virtual
4866 functions. However, that would require the vtable pointer in
4867 base classes to have a different type than the vtable pointer
4868 in derived classes. We could make that happen, but that
4869 still wouldn't solve all the problems. In particular, the
4870 type-based alias analysis code would decide that assignments
4871 to the base class vtable pointer can't alias assignments to
4872 the derived class vtable pointer, since they have different
4873 types. Thus, in a derived class destructor, where the base
4874 class constructor was inlined, we could generate bad code for
4875 setting up the vtable pointer.
4877 Therefore, we use one type for all vtable pointers. We still
4878 use a type-correct type; it's just doesn't indicate the array
4879 bounds. That's better than using `void*' or some such; it's
4880 cleaner, and it let's the alias analysis code know that these
4881 stores cannot alias stores to void*! */
4884 field = build_decl (input_location,
4885 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4886 DECL_VIRTUAL_P (field) = 1;
4887 DECL_ARTIFICIAL (field) = 1;
4888 DECL_FIELD_CONTEXT (field) = t;
4889 DECL_FCONTEXT (field) = t;
4890 if (TYPE_PACKED (t))
4891 DECL_PACKED (field) = 1;
4893 TYPE_VFIELD (t) = field;
4895 /* This class is non-empty. */
4896 CLASSTYPE_EMPTY_P (t) = 0;
4904 /* Add OFFSET to all base types of BINFO which is a base in the
4905 hierarchy dominated by T.
4907 OFFSET, which is a type offset, is number of bytes. */
4910 propagate_binfo_offsets (tree binfo, tree offset)
4916 /* Update BINFO's offset. */
4917 BINFO_OFFSET (binfo)
4918 = convert (sizetype,
4919 size_binop (PLUS_EXPR,
4920 convert (ssizetype, BINFO_OFFSET (binfo)),
4923 /* Find the primary base class. */
4924 primary_binfo = get_primary_binfo (binfo);
4926 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4927 propagate_binfo_offsets (primary_binfo, offset);
4929 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4931 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4933 /* Don't do the primary base twice. */
4934 if (base_binfo == primary_binfo)
4937 if (BINFO_VIRTUAL_P (base_binfo))
4940 propagate_binfo_offsets (base_binfo, offset);
4944 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4945 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4946 empty subobjects of T. */
4949 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4953 bool first_vbase = true;
4956 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4959 if (!abi_version_at_least(2))
4961 /* In G++ 3.2, we incorrectly rounded the size before laying out
4962 the virtual bases. */
4963 finish_record_layout (rli, /*free_p=*/false);
4964 #ifdef STRUCTURE_SIZE_BOUNDARY
4965 /* Packed structures don't need to have minimum size. */
4966 if (! TYPE_PACKED (t))
4967 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4969 rli->offset = TYPE_SIZE_UNIT (t);
4970 rli->bitpos = bitsize_zero_node;
4971 rli->record_align = TYPE_ALIGN (t);
4974 /* Find the last field. The artificial fields created for virtual
4975 bases will go after the last extant field to date. */
4976 next_field = &TYPE_FIELDS (t);
4978 next_field = &DECL_CHAIN (*next_field);
4980 /* Go through the virtual bases, allocating space for each virtual
4981 base that is not already a primary base class. These are
4982 allocated in inheritance graph order. */
4983 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4985 if (!BINFO_VIRTUAL_P (vbase))
4988 if (!BINFO_PRIMARY_P (vbase))
4990 tree basetype = TREE_TYPE (vbase);
4992 /* This virtual base is not a primary base of any class in the
4993 hierarchy, so we have to add space for it. */
4994 next_field = build_base_field (rli, vbase,
4995 offsets, next_field);
4997 /* If the first virtual base might have been placed at a
4998 lower address, had we started from CLASSTYPE_SIZE, rather
4999 than TYPE_SIZE, issue a warning. There can be both false
5000 positives and false negatives from this warning in rare
5001 cases; to deal with all the possibilities would probably
5002 require performing both layout algorithms and comparing
5003 the results which is not particularly tractable. */
5007 (size_binop (CEIL_DIV_EXPR,
5008 round_up_loc (input_location,
5010 CLASSTYPE_ALIGN (basetype)),
5012 BINFO_OFFSET (vbase))))
5014 "offset of virtual base %qT is not ABI-compliant and "
5015 "may change in a future version of GCC",
5018 first_vbase = false;
5023 /* Returns the offset of the byte just past the end of the base class
5027 end_of_base (tree binfo)
5031 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
5032 size = TYPE_SIZE_UNIT (char_type_node);
5033 else if (is_empty_class (BINFO_TYPE (binfo)))
5034 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
5035 allocate some space for it. It cannot have virtual bases, so
5036 TYPE_SIZE_UNIT is fine. */
5037 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5039 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5041 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
5044 /* Returns the offset of the byte just past the end of the base class
5045 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
5046 only non-virtual bases are included. */
5049 end_of_class (tree t, int include_virtuals_p)
5051 tree result = size_zero_node;
5052 VEC(tree,gc) *vbases;
5058 for (binfo = TYPE_BINFO (t), i = 0;
5059 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5061 if (!include_virtuals_p
5062 && BINFO_VIRTUAL_P (base_binfo)
5063 && (!BINFO_PRIMARY_P (base_binfo)
5064 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
5067 offset = end_of_base (base_binfo);
5068 if (INT_CST_LT_UNSIGNED (result, offset))
5072 /* G++ 3.2 did not check indirect virtual bases. */
5073 if (abi_version_at_least (2) && include_virtuals_p)
5074 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5075 VEC_iterate (tree, vbases, i, base_binfo); i++)
5077 offset = end_of_base (base_binfo);
5078 if (INT_CST_LT_UNSIGNED (result, offset))
5085 /* Warn about bases of T that are inaccessible because they are
5086 ambiguous. For example:
5089 struct T : public S {};
5090 struct U : public S, public T {};
5092 Here, `(S*) new U' is not allowed because there are two `S'
5096 warn_about_ambiguous_bases (tree t)
5099 VEC(tree,gc) *vbases;
5104 /* If there are no repeated bases, nothing can be ambiguous. */
5105 if (!CLASSTYPE_REPEATED_BASE_P (t))
5108 /* Check direct bases. */
5109 for (binfo = TYPE_BINFO (t), i = 0;
5110 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5112 basetype = BINFO_TYPE (base_binfo);
5114 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5115 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
5119 /* Check for ambiguous virtual bases. */
5121 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5122 VEC_iterate (tree, vbases, i, binfo); i++)
5124 basetype = BINFO_TYPE (binfo);
5126 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5127 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
5132 /* Compare two INTEGER_CSTs K1 and K2. */
5135 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
5137 return tree_int_cst_compare ((tree) k1, (tree) k2);
5140 /* Increase the size indicated in RLI to account for empty classes
5141 that are "off the end" of the class. */
5144 include_empty_classes (record_layout_info rli)
5149 /* It might be the case that we grew the class to allocate a
5150 zero-sized base class. That won't be reflected in RLI, yet,
5151 because we are willing to overlay multiple bases at the same
5152 offset. However, now we need to make sure that RLI is big enough
5153 to reflect the entire class. */
5154 eoc = end_of_class (rli->t,
5155 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
5156 rli_size = rli_size_unit_so_far (rli);
5157 if (TREE_CODE (rli_size) == INTEGER_CST
5158 && INT_CST_LT_UNSIGNED (rli_size, eoc))
5160 if (!abi_version_at_least (2))
5161 /* In version 1 of the ABI, the size of a class that ends with
5162 a bitfield was not rounded up to a whole multiple of a
5163 byte. Because rli_size_unit_so_far returns only the number
5164 of fully allocated bytes, any extra bits were not included
5166 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
5168 /* The size should have been rounded to a whole byte. */
5169 gcc_assert (tree_int_cst_equal
5170 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
5172 = size_binop (PLUS_EXPR,
5174 size_binop (MULT_EXPR,
5175 convert (bitsizetype,
5176 size_binop (MINUS_EXPR,
5178 bitsize_int (BITS_PER_UNIT)));
5179 normalize_rli (rli);
5183 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
5184 BINFO_OFFSETs for all of the base-classes. Position the vtable
5185 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
5188 layout_class_type (tree t, tree *virtuals_p)
5190 tree non_static_data_members;
5193 record_layout_info rli;
5194 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
5195 types that appear at that offset. */
5196 splay_tree empty_base_offsets;
5197 /* True if the last field layed out was a bit-field. */
5198 bool last_field_was_bitfield = false;
5199 /* The location at which the next field should be inserted. */
5201 /* T, as a base class. */
5204 /* Keep track of the first non-static data member. */
5205 non_static_data_members = TYPE_FIELDS (t);
5207 /* Start laying out the record. */
5208 rli = start_record_layout (t);
5210 /* Mark all the primary bases in the hierarchy. */
5211 determine_primary_bases (t);
5213 /* Create a pointer to our virtual function table. */
5214 vptr = create_vtable_ptr (t, virtuals_p);
5216 /* The vptr is always the first thing in the class. */
5219 DECL_CHAIN (vptr) = TYPE_FIELDS (t);
5220 TYPE_FIELDS (t) = vptr;
5221 next_field = &DECL_CHAIN (vptr);
5222 place_field (rli, vptr);
5225 next_field = &TYPE_FIELDS (t);
5227 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5228 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
5230 build_base_fields (rli, empty_base_offsets, next_field);
5232 /* Layout the non-static data members. */
5233 for (field = non_static_data_members; field; field = DECL_CHAIN (field))
5238 /* We still pass things that aren't non-static data members to
5239 the back end, in case it wants to do something with them. */
5240 if (TREE_CODE (field) != FIELD_DECL)
5242 place_field (rli, field);
5243 /* If the static data member has incomplete type, keep track
5244 of it so that it can be completed later. (The handling
5245 of pending statics in finish_record_layout is
5246 insufficient; consider:
5249 struct S2 { static S1 s1; };
5251 At this point, finish_record_layout will be called, but
5252 S1 is still incomplete.) */
5253 if (TREE_CODE (field) == VAR_DECL)
5255 maybe_register_incomplete_var (field);
5256 /* The visibility of static data members is determined
5257 at their point of declaration, not their point of
5259 determine_visibility (field);
5264 type = TREE_TYPE (field);
5265 if (type == error_mark_node)
5268 padding = NULL_TREE;
5270 /* If this field is a bit-field whose width is greater than its
5271 type, then there are some special rules for allocating
5273 if (DECL_C_BIT_FIELD (field)
5274 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
5278 bool was_unnamed_p = false;
5279 /* We must allocate the bits as if suitably aligned for the
5280 longest integer type that fits in this many bits. type
5281 of the field. Then, we are supposed to use the left over
5282 bits as additional padding. */
5283 for (itk = itk_char; itk != itk_none; ++itk)
5284 if (integer_types[itk] != NULL_TREE
5285 && (INT_CST_LT (size_int (MAX_FIXED_MODE_SIZE),
5286 TYPE_SIZE (integer_types[itk]))
5287 || INT_CST_LT (DECL_SIZE (field),
5288 TYPE_SIZE (integer_types[itk]))))
5291 /* ITK now indicates a type that is too large for the
5292 field. We have to back up by one to find the largest
5297 integer_type = integer_types[itk];
5298 } while (itk > 0 && integer_type == NULL_TREE);
5300 /* Figure out how much additional padding is required. GCC
5301 3.2 always created a padding field, even if it had zero
5303 if (!abi_version_at_least (2)
5304 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
5306 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
5307 /* In a union, the padding field must have the full width
5308 of the bit-field; all fields start at offset zero. */
5309 padding = DECL_SIZE (field);
5312 if (TREE_CODE (t) == UNION_TYPE)
5313 warning (OPT_Wabi, "size assigned to %qT may not be "
5314 "ABI-compliant and may change in a future "
5317 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
5318 TYPE_SIZE (integer_type));
5321 #ifdef PCC_BITFIELD_TYPE_MATTERS
5322 /* An unnamed bitfield does not normally affect the
5323 alignment of the containing class on a target where
5324 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5325 make any exceptions for unnamed bitfields when the
5326 bitfields are longer than their types. Therefore, we
5327 temporarily give the field a name. */
5328 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
5330 was_unnamed_p = true;
5331 DECL_NAME (field) = make_anon_name ();
5334 DECL_SIZE (field) = TYPE_SIZE (integer_type);
5335 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
5336 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
5337 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5338 empty_base_offsets);
5340 DECL_NAME (field) = NULL_TREE;
5341 /* Now that layout has been performed, set the size of the
5342 field to the size of its declared type; the rest of the
5343 field is effectively invisible. */
5344 DECL_SIZE (field) = TYPE_SIZE (type);
5345 /* We must also reset the DECL_MODE of the field. */
5346 if (abi_version_at_least (2))
5347 DECL_MODE (field) = TYPE_MODE (type);
5349 && DECL_MODE (field) != TYPE_MODE (type))
5350 /* Versions of G++ before G++ 3.4 did not reset the
5353 "the offset of %qD may not be ABI-compliant and may "
5354 "change in a future version of GCC", field);
5357 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5358 empty_base_offsets);
5360 /* Remember the location of any empty classes in FIELD. */
5361 if (abi_version_at_least (2))
5362 record_subobject_offsets (TREE_TYPE (field),
5363 byte_position(field),
5365 /*is_data_member=*/true);
5367 /* If a bit-field does not immediately follow another bit-field,
5368 and yet it starts in the middle of a byte, we have failed to
5369 comply with the ABI. */
5371 && DECL_C_BIT_FIELD (field)
5372 /* The TREE_NO_WARNING flag gets set by Objective-C when
5373 laying out an Objective-C class. The ObjC ABI differs
5374 from the C++ ABI, and so we do not want a warning
5376 && !TREE_NO_WARNING (field)
5377 && !last_field_was_bitfield
5378 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5379 DECL_FIELD_BIT_OFFSET (field),
5380 bitsize_unit_node)))
5381 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5382 "change in a future version of GCC", field);
5384 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5385 offset of the field. */
5387 && !abi_version_at_least (2)
5388 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5389 byte_position (field))
5390 && contains_empty_class_p (TREE_TYPE (field)))
5391 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5392 "classes to be placed at different locations in a "
5393 "future version of GCC", field);
5395 /* The middle end uses the type of expressions to determine the
5396 possible range of expression values. In order to optimize
5397 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5398 must be made aware of the width of "i", via its type.
5400 Because C++ does not have integer types of arbitrary width,
5401 we must (for the purposes of the front end) convert from the
5402 type assigned here to the declared type of the bitfield
5403 whenever a bitfield expression is used as an rvalue.
5404 Similarly, when assigning a value to a bitfield, the value
5405 must be converted to the type given the bitfield here. */
5406 if (DECL_C_BIT_FIELD (field))
5408 unsigned HOST_WIDE_INT width;
5409 tree ftype = TREE_TYPE (field);
5410 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5411 if (width != TYPE_PRECISION (ftype))
5414 = c_build_bitfield_integer_type (width,
5415 TYPE_UNSIGNED (ftype));
5417 = cp_build_qualified_type (TREE_TYPE (field),
5418 cp_type_quals (ftype));
5422 /* If we needed additional padding after this field, add it
5428 padding_field = build_decl (input_location,
5432 DECL_BIT_FIELD (padding_field) = 1;
5433 DECL_SIZE (padding_field) = padding;
5434 DECL_CONTEXT (padding_field) = t;
5435 DECL_ARTIFICIAL (padding_field) = 1;
5436 DECL_IGNORED_P (padding_field) = 1;
5437 layout_nonempty_base_or_field (rli, padding_field,
5439 empty_base_offsets);
5442 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5445 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5447 /* Make sure that we are on a byte boundary so that the size of
5448 the class without virtual bases will always be a round number
5450 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5451 normalize_rli (rli);
5454 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5456 if (!abi_version_at_least (2))
5457 include_empty_classes(rli);
5459 /* Delete all zero-width bit-fields from the list of fields. Now
5460 that the type is laid out they are no longer important. */
5461 remove_zero_width_bit_fields (t);
5463 /* Create the version of T used for virtual bases. We do not use
5464 make_class_type for this version; this is an artificial type. For
5465 a POD type, we just reuse T. */
5466 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5468 base_t = make_node (TREE_CODE (t));
5470 /* Set the size and alignment for the new type. In G++ 3.2, all
5471 empty classes were considered to have size zero when used as
5473 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5475 TYPE_SIZE (base_t) = bitsize_zero_node;
5476 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5477 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5479 "layout of classes derived from empty class %qT "
5480 "may change in a future version of GCC",
5487 /* If the ABI version is not at least two, and the last
5488 field was a bit-field, RLI may not be on a byte
5489 boundary. In particular, rli_size_unit_so_far might
5490 indicate the last complete byte, while rli_size_so_far
5491 indicates the total number of bits used. Therefore,
5492 rli_size_so_far, rather than rli_size_unit_so_far, is
5493 used to compute TYPE_SIZE_UNIT. */
5494 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5495 TYPE_SIZE_UNIT (base_t)
5496 = size_binop (MAX_EXPR,
5498 size_binop (CEIL_DIV_EXPR,
5499 rli_size_so_far (rli),
5500 bitsize_int (BITS_PER_UNIT))),
5503 = size_binop (MAX_EXPR,
5504 rli_size_so_far (rli),
5505 size_binop (MULT_EXPR,
5506 convert (bitsizetype, eoc),
5507 bitsize_int (BITS_PER_UNIT)));
5509 TYPE_ALIGN (base_t) = rli->record_align;
5510 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5512 /* Copy the fields from T. */
5513 next_field = &TYPE_FIELDS (base_t);
5514 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5515 if (TREE_CODE (field) == FIELD_DECL)
5517 *next_field = build_decl (input_location,
5521 DECL_CONTEXT (*next_field) = base_t;
5522 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5523 DECL_FIELD_BIT_OFFSET (*next_field)
5524 = DECL_FIELD_BIT_OFFSET (field);
5525 DECL_SIZE (*next_field) = DECL_SIZE (field);
5526 DECL_MODE (*next_field) = DECL_MODE (field);
5527 next_field = &DECL_CHAIN (*next_field);
5530 /* Record the base version of the type. */
5531 CLASSTYPE_AS_BASE (t) = base_t;
5532 TYPE_CONTEXT (base_t) = t;
5535 CLASSTYPE_AS_BASE (t) = t;
5537 /* Every empty class contains an empty class. */
5538 if (CLASSTYPE_EMPTY_P (t))
5539 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5541 /* Set the TYPE_DECL for this type to contain the right
5542 value for DECL_OFFSET, so that we can use it as part
5543 of a COMPONENT_REF for multiple inheritance. */
5544 layout_decl (TYPE_MAIN_DECL (t), 0);
5546 /* Now fix up any virtual base class types that we left lying
5547 around. We must get these done before we try to lay out the
5548 virtual function table. As a side-effect, this will remove the
5549 base subobject fields. */
5550 layout_virtual_bases (rli, empty_base_offsets);
5552 /* Make sure that empty classes are reflected in RLI at this
5554 include_empty_classes(rli);
5556 /* Make sure not to create any structures with zero size. */
5557 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5559 build_decl (input_location,
5560 FIELD_DECL, NULL_TREE, char_type_node));
5562 /* If this is a non-POD, declaring it packed makes a difference to how it
5563 can be used as a field; don't let finalize_record_size undo it. */
5564 if (TYPE_PACKED (t) && !layout_pod_type_p (t))
5565 rli->packed_maybe_necessary = true;
5567 /* Let the back end lay out the type. */
5568 finish_record_layout (rli, /*free_p=*/true);
5570 /* Warn about bases that can't be talked about due to ambiguity. */
5571 warn_about_ambiguous_bases (t);
5573 /* Now that we're done with layout, give the base fields the real types. */
5574 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5575 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5576 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5579 splay_tree_delete (empty_base_offsets);
5581 if (CLASSTYPE_EMPTY_P (t)
5582 && tree_int_cst_lt (sizeof_biggest_empty_class,
5583 TYPE_SIZE_UNIT (t)))
5584 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5587 /* Determine the "key method" for the class type indicated by TYPE,
5588 and set CLASSTYPE_KEY_METHOD accordingly. */
5591 determine_key_method (tree type)
5595 if (TYPE_FOR_JAVA (type)
5596 || processing_template_decl
5597 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5598 || CLASSTYPE_INTERFACE_KNOWN (type))
5601 /* The key method is the first non-pure virtual function that is not
5602 inline at the point of class definition. On some targets the
5603 key function may not be inline; those targets should not call
5604 this function until the end of the translation unit. */
5605 for (method = TYPE_METHODS (type); method != NULL_TREE;
5606 method = DECL_CHAIN (method))
5607 if (DECL_VINDEX (method) != NULL_TREE
5608 && ! DECL_DECLARED_INLINE_P (method)
5609 && ! DECL_PURE_VIRTUAL_P (method))
5611 CLASSTYPE_KEY_METHOD (type) = method;
5618 /* Perform processing required when the definition of T (a class type)
5622 finish_struct_1 (tree t)
5625 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5626 tree virtuals = NULL_TREE;
5629 if (COMPLETE_TYPE_P (t))
5631 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5632 error ("redefinition of %q#T", t);
5637 /* If this type was previously laid out as a forward reference,
5638 make sure we lay it out again. */
5639 TYPE_SIZE (t) = NULL_TREE;
5640 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5642 /* Make assumptions about the class; we'll reset the flags if
5644 CLASSTYPE_EMPTY_P (t) = 1;
5645 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5646 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5647 CLASSTYPE_LITERAL_P (t) = true;
5649 /* Do end-of-class semantic processing: checking the validity of the
5650 bases and members and add implicitly generated methods. */
5651 check_bases_and_members (t);
5653 /* Find the key method. */
5654 if (TYPE_CONTAINS_VPTR_P (t))
5656 /* The Itanium C++ ABI permits the key method to be chosen when
5657 the class is defined -- even though the key method so
5658 selected may later turn out to be an inline function. On
5659 some systems (such as ARM Symbian OS) the key method cannot
5660 be determined until the end of the translation unit. On such
5661 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5662 will cause the class to be added to KEYED_CLASSES. Then, in
5663 finish_file we will determine the key method. */
5664 if (targetm.cxx.key_method_may_be_inline ())
5665 determine_key_method (t);
5667 /* If a polymorphic class has no key method, we may emit the vtable
5668 in every translation unit where the class definition appears. */
5669 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5670 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5673 /* Layout the class itself. */
5674 layout_class_type (t, &virtuals);
5675 if (CLASSTYPE_AS_BASE (t) != t)
5676 /* We use the base type for trivial assignments, and hence it
5678 compute_record_mode (CLASSTYPE_AS_BASE (t));
5680 virtuals = modify_all_vtables (t, nreverse (virtuals));
5682 /* If necessary, create the primary vtable for this class. */
5683 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5685 /* We must enter these virtuals into the table. */
5686 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5687 build_primary_vtable (NULL_TREE, t);
5688 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5689 /* Here we know enough to change the type of our virtual
5690 function table, but we will wait until later this function. */
5691 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5694 if (TYPE_CONTAINS_VPTR_P (t))
5699 if (BINFO_VTABLE (TYPE_BINFO (t)))
5700 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5701 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5702 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5704 /* Add entries for virtual functions introduced by this class. */
5705 BINFO_VIRTUALS (TYPE_BINFO (t))
5706 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5708 /* Set DECL_VINDEX for all functions declared in this class. */
5709 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5711 fn = TREE_CHAIN (fn),
5712 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5713 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5715 tree fndecl = BV_FN (fn);
5717 if (DECL_THUNK_P (fndecl))
5718 /* A thunk. We should never be calling this entry directly
5719 from this vtable -- we'd use the entry for the non
5720 thunk base function. */
5721 DECL_VINDEX (fndecl) = NULL_TREE;
5722 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5723 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5727 finish_struct_bits (t);
5729 /* Complete the rtl for any static member objects of the type we're
5731 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
5732 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5733 && TREE_TYPE (x) != error_mark_node
5734 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5735 DECL_MODE (x) = TYPE_MODE (t);
5737 /* Done with FIELDS...now decide whether to sort these for
5738 faster lookups later.
5740 We use a small number because most searches fail (succeeding
5741 ultimately as the search bores through the inheritance
5742 hierarchy), and we want this failure to occur quickly. */
5744 n_fields = count_fields (TYPE_FIELDS (t));
5747 struct sorted_fields_type *field_vec = ggc_alloc_sorted_fields_type
5748 (sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5749 field_vec->len = n_fields;
5750 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5751 qsort (field_vec->elts, n_fields, sizeof (tree),
5753 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
5756 /* Complain if one of the field types requires lower visibility. */
5757 constrain_class_visibility (t);
5759 /* Make the rtl for any new vtables we have created, and unmark
5760 the base types we marked. */
5763 /* Build the VTT for T. */
5766 /* This warning does not make sense for Java classes, since they
5767 cannot have destructors. */
5768 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5772 dtor = CLASSTYPE_DESTRUCTORS (t);
5773 if (/* An implicitly declared destructor is always public. And,
5774 if it were virtual, we would have created it by now. */
5776 || (!DECL_VINDEX (dtor)
5777 && (/* public non-virtual */
5778 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5779 || (/* non-public non-virtual with friends */
5780 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5781 && (CLASSTYPE_FRIEND_CLASSES (t)
5782 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5783 warning (OPT_Wnon_virtual_dtor,
5784 "%q#T has virtual functions and accessible"
5785 " non-virtual destructor", t);
5790 if (warn_overloaded_virtual)
5793 /* Class layout, assignment of virtual table slots, etc., is now
5794 complete. Give the back end a chance to tweak the visibility of
5795 the class or perform any other required target modifications. */
5796 targetm.cxx.adjust_class_at_definition (t);
5798 maybe_suppress_debug_info (t);
5800 dump_class_hierarchy (t);
5802 /* Finish debugging output for this type. */
5803 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5806 /* When T was built up, the member declarations were added in reverse
5807 order. Rearrange them to declaration order. */
5810 unreverse_member_declarations (tree t)
5816 /* The following lists are all in reverse order. Put them in
5817 declaration order now. */
5818 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5819 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5821 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5822 reverse order, so we can't just use nreverse. */
5824 for (x = TYPE_FIELDS (t);
5825 x && TREE_CODE (x) != TYPE_DECL;
5828 next = DECL_CHAIN (x);
5829 DECL_CHAIN (x) = prev;
5834 DECL_CHAIN (TYPE_FIELDS (t)) = x;
5836 TYPE_FIELDS (t) = prev;
5841 finish_struct (tree t, tree attributes)
5843 location_t saved_loc = input_location;
5845 /* Now that we've got all the field declarations, reverse everything
5847 unreverse_member_declarations (t);
5849 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5851 /* Nadger the current location so that diagnostics point to the start of
5852 the struct, not the end. */
5853 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5855 if (processing_template_decl)
5859 finish_struct_methods (t);
5860 TYPE_SIZE (t) = bitsize_zero_node;
5861 TYPE_SIZE_UNIT (t) = size_zero_node;
5863 /* We need to emit an error message if this type was used as a parameter
5864 and it is an abstract type, even if it is a template. We construct
5865 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5866 account and we call complete_vars with this type, which will check
5867 the PARM_DECLS. Note that while the type is being defined,
5868 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5869 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5870 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5871 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
5872 if (DECL_PURE_VIRTUAL_P (x))
5873 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5876 /* Remember current #pragma pack value. */
5877 TYPE_PRECISION (t) = maximum_field_alignment;
5880 finish_struct_1 (t);
5882 input_location = saved_loc;
5884 TYPE_BEING_DEFINED (t) = 0;
5886 if (current_class_type)
5889 error ("trying to finish struct, but kicked out due to previous parse errors");
5891 if (processing_template_decl && at_function_scope_p ())
5892 add_stmt (build_min (TAG_DEFN, t));
5897 /* Return the dynamic type of INSTANCE, if known.
5898 Used to determine whether the virtual function table is needed
5901 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5902 of our knowledge of its type. *NONNULL should be initialized
5903 before this function is called. */
5906 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5908 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5910 switch (TREE_CODE (instance))
5913 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5916 return RECUR (TREE_OPERAND (instance, 0));
5919 /* This is a call to a constructor, hence it's never zero. */
5920 if (TREE_HAS_CONSTRUCTOR (instance))
5924 return TREE_TYPE (instance);
5929 /* This is a call to a constructor, hence it's never zero. */
5930 if (TREE_HAS_CONSTRUCTOR (instance))
5934 return TREE_TYPE (instance);
5936 return RECUR (TREE_OPERAND (instance, 0));
5938 case POINTER_PLUS_EXPR:
5941 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5942 return RECUR (TREE_OPERAND (instance, 0));
5943 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5944 /* Propagate nonnull. */
5945 return RECUR (TREE_OPERAND (instance, 0));
5950 return RECUR (TREE_OPERAND (instance, 0));
5953 instance = TREE_OPERAND (instance, 0);
5956 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5957 with a real object -- given &p->f, p can still be null. */
5958 tree t = get_base_address (instance);
5959 /* ??? Probably should check DECL_WEAK here. */
5960 if (t && DECL_P (t))
5963 return RECUR (instance);
5966 /* If this component is really a base class reference, then the field
5967 itself isn't definitive. */
5968 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5969 return RECUR (TREE_OPERAND (instance, 0));
5970 return RECUR (TREE_OPERAND (instance, 1));
5974 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5975 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
5979 return TREE_TYPE (TREE_TYPE (instance));
5981 /* fall through... */
5985 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
5989 return TREE_TYPE (instance);
5991 else if (instance == current_class_ptr)
5996 /* if we're in a ctor or dtor, we know our type. */
5997 if (DECL_LANG_SPECIFIC (current_function_decl)
5998 && (DECL_CONSTRUCTOR_P (current_function_decl)
5999 || DECL_DESTRUCTOR_P (current_function_decl)))
6003 return TREE_TYPE (TREE_TYPE (instance));
6006 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
6008 /* We only need one hash table because it is always left empty. */
6011 ht = htab_create (37,
6016 /* Reference variables should be references to objects. */
6020 /* Enter the INSTANCE in a table to prevent recursion; a
6021 variable's initializer may refer to the variable
6023 if (TREE_CODE (instance) == VAR_DECL
6024 && DECL_INITIAL (instance)
6025 && !type_dependent_expression_p_push (DECL_INITIAL (instance))
6026 && !htab_find (ht, instance))
6031 slot = htab_find_slot (ht, instance, INSERT);
6033 type = RECUR (DECL_INITIAL (instance));
6034 htab_remove_elt (ht, instance);
6047 /* Return nonzero if the dynamic type of INSTANCE is known, and
6048 equivalent to the static type. We also handle the case where
6049 INSTANCE is really a pointer. Return negative if this is a
6050 ctor/dtor. There the dynamic type is known, but this might not be
6051 the most derived base of the original object, and hence virtual
6052 bases may not be layed out according to this type.
6054 Used to determine whether the virtual function table is needed
6057 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6058 of our knowledge of its type. *NONNULL should be initialized
6059 before this function is called. */
6062 resolves_to_fixed_type_p (tree instance, int* nonnull)
6064 tree t = TREE_TYPE (instance);
6068 if (processing_template_decl)
6070 /* In a template we only care about the type of the result. */
6076 fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
6077 if (fixed == NULL_TREE)
6079 if (POINTER_TYPE_P (t))
6081 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
6083 return cdtorp ? -1 : 1;
6088 init_class_processing (void)
6090 current_class_depth = 0;
6091 current_class_stack_size = 10;
6093 = XNEWVEC (struct class_stack_node, current_class_stack_size);
6094 local_classes = VEC_alloc (tree, gc, 8);
6095 sizeof_biggest_empty_class = size_zero_node;
6097 ridpointers[(int) RID_PUBLIC] = access_public_node;
6098 ridpointers[(int) RID_PRIVATE] = access_private_node;
6099 ridpointers[(int) RID_PROTECTED] = access_protected_node;
6102 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
6105 restore_class_cache (void)
6109 /* We are re-entering the same class we just left, so we don't
6110 have to search the whole inheritance matrix to find all the
6111 decls to bind again. Instead, we install the cached
6112 class_shadowed list and walk through it binding names. */
6113 push_binding_level (previous_class_level);
6114 class_binding_level = previous_class_level;
6115 /* Restore IDENTIFIER_TYPE_VALUE. */
6116 for (type = class_binding_level->type_shadowed;
6118 type = TREE_CHAIN (type))
6119 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
6122 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
6123 appropriate for TYPE.
6125 So that we may avoid calls to lookup_name, we cache the _TYPE
6126 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
6128 For multiple inheritance, we perform a two-pass depth-first search
6129 of the type lattice. */
6132 pushclass (tree type)
6134 class_stack_node_t csn;
6136 type = TYPE_MAIN_VARIANT (type);
6138 /* Make sure there is enough room for the new entry on the stack. */
6139 if (current_class_depth + 1 >= current_class_stack_size)
6141 current_class_stack_size *= 2;
6143 = XRESIZEVEC (struct class_stack_node, current_class_stack,
6144 current_class_stack_size);
6147 /* Insert a new entry on the class stack. */
6148 csn = current_class_stack + current_class_depth;
6149 csn->name = current_class_name;
6150 csn->type = current_class_type;
6151 csn->access = current_access_specifier;
6152 csn->names_used = 0;
6154 current_class_depth++;
6156 /* Now set up the new type. */
6157 current_class_name = TYPE_NAME (type);
6158 if (TREE_CODE (current_class_name) == TYPE_DECL)
6159 current_class_name = DECL_NAME (current_class_name);
6160 current_class_type = type;
6162 /* By default, things in classes are private, while things in
6163 structures or unions are public. */
6164 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
6165 ? access_private_node
6166 : access_public_node);
6168 if (previous_class_level
6169 && type != previous_class_level->this_entity
6170 && current_class_depth == 1)
6172 /* Forcibly remove any old class remnants. */
6173 invalidate_class_lookup_cache ();
6176 if (!previous_class_level
6177 || type != previous_class_level->this_entity
6178 || current_class_depth > 1)
6181 restore_class_cache ();
6184 /* When we exit a toplevel class scope, we save its binding level so
6185 that we can restore it quickly. Here, we've entered some other
6186 class, so we must invalidate our cache. */
6189 invalidate_class_lookup_cache (void)
6191 previous_class_level = NULL;
6194 /* Get out of the current class scope. If we were in a class scope
6195 previously, that is the one popped to. */
6202 current_class_depth--;
6203 current_class_name = current_class_stack[current_class_depth].name;
6204 current_class_type = current_class_stack[current_class_depth].type;
6205 current_access_specifier = current_class_stack[current_class_depth].access;
6206 if (current_class_stack[current_class_depth].names_used)
6207 splay_tree_delete (current_class_stack[current_class_depth].names_used);
6210 /* Mark the top of the class stack as hidden. */
6213 push_class_stack (void)
6215 if (current_class_depth)
6216 ++current_class_stack[current_class_depth - 1].hidden;
6219 /* Mark the top of the class stack as un-hidden. */
6222 pop_class_stack (void)
6224 if (current_class_depth)
6225 --current_class_stack[current_class_depth - 1].hidden;
6228 /* Returns 1 if the class type currently being defined is either T or
6229 a nested type of T. */
6232 currently_open_class (tree t)
6236 if (!CLASS_TYPE_P (t))
6239 t = TYPE_MAIN_VARIANT (t);
6241 /* We start looking from 1 because entry 0 is from global scope,
6243 for (i = current_class_depth; i > 0; --i)
6246 if (i == current_class_depth)
6247 c = current_class_type;
6250 if (current_class_stack[i].hidden)
6252 c = current_class_stack[i].type;
6256 if (same_type_p (c, t))
6262 /* If either current_class_type or one of its enclosing classes are derived
6263 from T, return the appropriate type. Used to determine how we found
6264 something via unqualified lookup. */
6267 currently_open_derived_class (tree t)
6271 /* The bases of a dependent type are unknown. */
6272 if (dependent_type_p (t))
6275 if (!current_class_type)
6278 if (DERIVED_FROM_P (t, current_class_type))
6279 return current_class_type;
6281 for (i = current_class_depth - 1; i > 0; --i)
6283 if (current_class_stack[i].hidden)
6285 if (DERIVED_FROM_P (t, current_class_stack[i].type))
6286 return current_class_stack[i].type;
6292 /* Returns the innermost class type which is not a lambda closure type. */
6295 current_nonlambda_class_type (void)
6299 /* We start looking from 1 because entry 0 is from global scope,
6301 for (i = current_class_depth; i > 0; --i)
6304 if (i == current_class_depth)
6305 c = current_class_type;
6308 if (current_class_stack[i].hidden)
6310 c = current_class_stack[i].type;
6314 if (!LAMBDA_TYPE_P (c))
6320 /* When entering a class scope, all enclosing class scopes' names with
6321 static meaning (static variables, static functions, types and
6322 enumerators) have to be visible. This recursive function calls
6323 pushclass for all enclosing class contexts until global or a local
6324 scope is reached. TYPE is the enclosed class. */
6327 push_nested_class (tree type)
6329 /* A namespace might be passed in error cases, like A::B:C. */
6330 if (type == NULL_TREE
6331 || !CLASS_TYPE_P (type))
6334 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
6339 /* Undoes a push_nested_class call. */
6342 pop_nested_class (void)
6344 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
6347 if (context && CLASS_TYPE_P (context))
6348 pop_nested_class ();
6351 /* Returns the number of extern "LANG" blocks we are nested within. */
6354 current_lang_depth (void)
6356 return VEC_length (tree, current_lang_base);
6359 /* Set global variables CURRENT_LANG_NAME to appropriate value
6360 so that behavior of name-mangling machinery is correct. */
6363 push_lang_context (tree name)
6365 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
6367 if (name == lang_name_cplusplus)
6369 current_lang_name = name;
6371 else if (name == lang_name_java)
6373 current_lang_name = name;
6374 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6375 (See record_builtin_java_type in decl.c.) However, that causes
6376 incorrect debug entries if these types are actually used.
6377 So we re-enable debug output after extern "Java". */
6378 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
6379 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
6380 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
6381 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
6382 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
6383 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
6384 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
6385 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
6387 else if (name == lang_name_c)
6389 current_lang_name = name;
6392 error ("language string %<\"%E\"%> not recognized", name);
6395 /* Get out of the current language scope. */
6398 pop_lang_context (void)
6400 current_lang_name = VEC_pop (tree, current_lang_base);
6403 /* Type instantiation routines. */
6405 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6406 matches the TARGET_TYPE. If there is no satisfactory match, return
6407 error_mark_node, and issue an error & warning messages under
6408 control of FLAGS. Permit pointers to member function if FLAGS
6409 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6410 a template-id, and EXPLICIT_TARGS are the explicitly provided
6413 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6414 is the base path used to reference those member functions. If
6415 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6416 resolved to a member function, access checks will be performed and
6417 errors issued if appropriate. */
6420 resolve_address_of_overloaded_function (tree target_type,
6422 tsubst_flags_t flags,
6424 tree explicit_targs,
6427 /* Here's what the standard says:
6431 If the name is a function template, template argument deduction
6432 is done, and if the argument deduction succeeds, the deduced
6433 arguments are used to generate a single template function, which
6434 is added to the set of overloaded functions considered.
6436 Non-member functions and static member functions match targets of
6437 type "pointer-to-function" or "reference-to-function." Nonstatic
6438 member functions match targets of type "pointer-to-member
6439 function;" the function type of the pointer to member is used to
6440 select the member function from the set of overloaded member
6441 functions. If a nonstatic member function is selected, the
6442 reference to the overloaded function name is required to have the
6443 form of a pointer to member as described in 5.3.1.
6445 If more than one function is selected, any template functions in
6446 the set are eliminated if the set also contains a non-template
6447 function, and any given template function is eliminated if the
6448 set contains a second template function that is more specialized
6449 than the first according to the partial ordering rules 14.5.5.2.
6450 After such eliminations, if any, there shall remain exactly one
6451 selected function. */
6454 /* We store the matches in a TREE_LIST rooted here. The functions
6455 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6456 interoperability with most_specialized_instantiation. */
6457 tree matches = NULL_TREE;
6459 tree target_fn_type;
6461 /* By the time we get here, we should be seeing only real
6462 pointer-to-member types, not the internal POINTER_TYPE to
6463 METHOD_TYPE representation. */
6464 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6465 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6467 gcc_assert (is_overloaded_fn (overload));
6469 /* Check that the TARGET_TYPE is reasonable. */
6470 if (TYPE_PTRFN_P (target_type))
6472 else if (TYPE_PTRMEMFUNC_P (target_type))
6473 /* This is OK, too. */
6475 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6476 /* This is OK, too. This comes from a conversion to reference
6478 target_type = build_reference_type (target_type);
6481 if (flags & tf_error)
6482 error ("cannot resolve overloaded function %qD based on"
6483 " conversion to type %qT",
6484 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6485 return error_mark_node;
6488 /* Non-member functions and static member functions match targets of type
6489 "pointer-to-function" or "reference-to-function." Nonstatic member
6490 functions match targets of type "pointer-to-member-function;" the
6491 function type of the pointer to member is used to select the member
6492 function from the set of overloaded member functions.
6494 So figure out the FUNCTION_TYPE that we want to match against. */
6495 target_fn_type = static_fn_type (target_type);
6497 /* If we can find a non-template function that matches, we can just
6498 use it. There's no point in generating template instantiations
6499 if we're just going to throw them out anyhow. But, of course, we
6500 can only do this when we don't *need* a template function. */
6505 for (fns = overload; fns; fns = OVL_NEXT (fns))
6507 tree fn = OVL_CURRENT (fns);
6509 if (TREE_CODE (fn) == TEMPLATE_DECL)
6510 /* We're not looking for templates just yet. */
6513 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6515 /* We're looking for a non-static member, and this isn't
6516 one, or vice versa. */
6519 /* Ignore functions which haven't been explicitly
6521 if (DECL_ANTICIPATED (fn))
6524 /* See if there's a match. */
6525 if (same_type_p (target_fn_type, static_fn_type (fn)))
6526 matches = tree_cons (fn, NULL_TREE, matches);
6530 /* Now, if we've already got a match (or matches), there's no need
6531 to proceed to the template functions. But, if we don't have a
6532 match we need to look at them, too. */
6535 tree target_arg_types;
6536 tree target_ret_type;
6539 unsigned int nargs, ia;
6542 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6543 target_ret_type = TREE_TYPE (target_fn_type);
6545 nargs = list_length (target_arg_types);
6546 args = XALLOCAVEC (tree, nargs);
6547 for (arg = target_arg_types, ia = 0;
6548 arg != NULL_TREE && arg != void_list_node;
6549 arg = TREE_CHAIN (arg), ++ia)
6550 args[ia] = TREE_VALUE (arg);
6553 for (fns = overload; fns; fns = OVL_NEXT (fns))
6555 tree fn = OVL_CURRENT (fns);
6559 if (TREE_CODE (fn) != TEMPLATE_DECL)
6560 /* We're only looking for templates. */
6563 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6565 /* We're not looking for a non-static member, and this is
6566 one, or vice versa. */
6569 /* Try to do argument deduction. */
6570 targs = make_tree_vec (DECL_NTPARMS (fn));
6571 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6572 target_ret_type, DEDUCE_EXACT,
6574 /* Argument deduction failed. */
6577 /* Instantiate the template. */
6578 instantiation = instantiate_template (fn, targs, flags);
6579 if (instantiation == error_mark_node)
6580 /* Instantiation failed. */
6583 /* See if there's a match. */
6584 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
6585 matches = tree_cons (instantiation, fn, matches);
6588 /* Now, remove all but the most specialized of the matches. */
6591 tree match = most_specialized_instantiation (matches);
6593 if (match != error_mark_node)
6594 matches = tree_cons (TREE_PURPOSE (match),
6600 /* Now we should have exactly one function in MATCHES. */
6601 if (matches == NULL_TREE)
6603 /* There were *no* matches. */
6604 if (flags & tf_error)
6606 error ("no matches converting function %qD to type %q#T",
6607 DECL_NAME (OVL_CURRENT (overload)),
6610 print_candidates (overload);
6612 return error_mark_node;
6614 else if (TREE_CHAIN (matches))
6616 /* There were too many matches. First check if they're all
6617 the same function. */
6620 fn = TREE_PURPOSE (matches);
6621 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6622 if (!decls_match (fn, TREE_PURPOSE (match)))
6627 if (flags & tf_error)
6629 error ("converting overloaded function %qD to type %q#T is ambiguous",
6630 DECL_NAME (OVL_FUNCTION (overload)),
6633 /* Since print_candidates expects the functions in the
6634 TREE_VALUE slot, we flip them here. */
6635 for (match = matches; match; match = TREE_CHAIN (match))
6636 TREE_VALUE (match) = TREE_PURPOSE (match);
6638 print_candidates (matches);
6641 return error_mark_node;
6645 /* Good, exactly one match. Now, convert it to the correct type. */
6646 fn = TREE_PURPOSE (matches);
6648 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6649 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6651 static int explained;
6653 if (!(flags & tf_error))
6654 return error_mark_node;
6656 permerror (input_location, "assuming pointer to member %qD", fn);
6659 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6664 /* If we're doing overload resolution purely for the purpose of
6665 determining conversion sequences, we should not consider the
6666 function used. If this conversion sequence is selected, the
6667 function will be marked as used at this point. */
6668 if (!(flags & tf_conv))
6670 /* Make =delete work with SFINAE. */
6671 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6672 return error_mark_node;
6677 /* We could not check access to member functions when this
6678 expression was originally created since we did not know at that
6679 time to which function the expression referred. */
6680 if (!(flags & tf_no_access_control)
6681 && DECL_FUNCTION_MEMBER_P (fn))
6683 gcc_assert (access_path);
6684 perform_or_defer_access_check (access_path, fn, fn);
6687 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6688 return cp_build_addr_expr (fn, flags);
6691 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6692 will mark the function as addressed, but here we must do it
6694 cxx_mark_addressable (fn);
6700 /* This function will instantiate the type of the expression given in
6701 RHS to match the type of LHSTYPE. If errors exist, then return
6702 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6703 we complain on errors. If we are not complaining, never modify rhs,
6704 as overload resolution wants to try many possible instantiations, in
6705 the hope that at least one will work.
6707 For non-recursive calls, LHSTYPE should be a function, pointer to
6708 function, or a pointer to member function. */
6711 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6713 tsubst_flags_t flags_in = flags;
6714 tree access_path = NULL_TREE;
6716 flags &= ~tf_ptrmem_ok;
6718 if (lhstype == unknown_type_node)
6720 if (flags & tf_error)
6721 error ("not enough type information");
6722 return error_mark_node;
6725 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6727 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6729 if (flag_ms_extensions
6730 && TYPE_PTRMEMFUNC_P (lhstype)
6731 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6732 /* Microsoft allows `A::f' to be resolved to a
6733 pointer-to-member. */
6737 if (flags & tf_error)
6738 error ("argument of type %qT does not match %qT",
6739 TREE_TYPE (rhs), lhstype);
6740 return error_mark_node;
6744 if (TREE_CODE (rhs) == BASELINK)
6746 access_path = BASELINK_ACCESS_BINFO (rhs);
6747 rhs = BASELINK_FUNCTIONS (rhs);
6750 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6751 deduce any type information. */
6752 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6754 if (flags & tf_error)
6755 error ("not enough type information");
6756 return error_mark_node;
6759 /* There only a few kinds of expressions that may have a type
6760 dependent on overload resolution. */
6761 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6762 || TREE_CODE (rhs) == COMPONENT_REF
6763 || really_overloaded_fn (rhs)
6764 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
6766 /* This should really only be used when attempting to distinguish
6767 what sort of a pointer to function we have. For now, any
6768 arithmetic operation which is not supported on pointers
6769 is rejected as an error. */
6771 switch (TREE_CODE (rhs))
6775 tree member = TREE_OPERAND (rhs, 1);
6777 member = instantiate_type (lhstype, member, flags);
6778 if (member != error_mark_node
6779 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6780 /* Do not lose object's side effects. */
6781 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6782 TREE_OPERAND (rhs, 0), member);
6787 rhs = TREE_OPERAND (rhs, 1);
6788 if (BASELINK_P (rhs))
6789 return instantiate_type (lhstype, rhs, flags_in);
6791 /* This can happen if we are forming a pointer-to-member for a
6793 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6797 case TEMPLATE_ID_EXPR:
6799 tree fns = TREE_OPERAND (rhs, 0);
6800 tree args = TREE_OPERAND (rhs, 1);
6803 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6804 /*template_only=*/true,
6811 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6812 /*template_only=*/false,
6813 /*explicit_targs=*/NULL_TREE,
6818 if (PTRMEM_OK_P (rhs))
6819 flags |= tf_ptrmem_ok;
6821 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6825 return error_mark_node;
6830 return error_mark_node;
6833 /* Return the name of the virtual function pointer field
6834 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6835 this may have to look back through base types to find the
6836 ultimate field name. (For single inheritance, these could
6837 all be the same name. Who knows for multiple inheritance). */
6840 get_vfield_name (tree type)
6842 tree binfo, base_binfo;
6845 for (binfo = TYPE_BINFO (type);
6846 BINFO_N_BASE_BINFOS (binfo);
6849 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6851 if (BINFO_VIRTUAL_P (base_binfo)
6852 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6856 type = BINFO_TYPE (binfo);
6857 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6858 + TYPE_NAME_LENGTH (type) + 2);
6859 sprintf (buf, VFIELD_NAME_FORMAT,
6860 IDENTIFIER_POINTER (constructor_name (type)));
6861 return get_identifier (buf);
6865 print_class_statistics (void)
6867 #ifdef GATHER_STATISTICS
6868 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6869 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6872 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6873 n_vtables, n_vtable_searches);
6874 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6875 n_vtable_entries, n_vtable_elems);
6880 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6881 according to [class]:
6882 The class-name is also inserted
6883 into the scope of the class itself. For purposes of access checking,
6884 the inserted class name is treated as if it were a public member name. */
6887 build_self_reference (void)
6889 tree name = constructor_name (current_class_type);
6890 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6893 DECL_NONLOCAL (value) = 1;
6894 DECL_CONTEXT (value) = current_class_type;
6895 DECL_ARTIFICIAL (value) = 1;
6896 SET_DECL_SELF_REFERENCE_P (value);
6897 set_underlying_type (value);
6899 if (processing_template_decl)
6900 value = push_template_decl (value);
6902 saved_cas = current_access_specifier;
6903 current_access_specifier = access_public_node;
6904 finish_member_declaration (value);
6905 current_access_specifier = saved_cas;
6908 /* Returns 1 if TYPE contains only padding bytes. */
6911 is_empty_class (tree type)
6913 if (type == error_mark_node)
6916 if (! CLASS_TYPE_P (type))
6919 /* In G++ 3.2, whether or not a class was empty was determined by
6920 looking at its size. */
6921 if (abi_version_at_least (2))
6922 return CLASSTYPE_EMPTY_P (type);
6924 return integer_zerop (CLASSTYPE_SIZE (type));
6927 /* Returns true if TYPE contains an empty class. */
6930 contains_empty_class_p (tree type)
6932 if (is_empty_class (type))
6934 if (CLASS_TYPE_P (type))
6941 for (binfo = TYPE_BINFO (type), i = 0;
6942 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6943 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6945 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6946 if (TREE_CODE (field) == FIELD_DECL
6947 && !DECL_ARTIFICIAL (field)
6948 && is_empty_class (TREE_TYPE (field)))
6951 else if (TREE_CODE (type) == ARRAY_TYPE)
6952 return contains_empty_class_p (TREE_TYPE (type));
6956 /* Returns true if TYPE contains no actual data, just various
6957 possible combinations of empty classes and possibly a vptr. */
6960 is_really_empty_class (tree type)
6962 if (CLASS_TYPE_P (type))
6969 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
6970 out, but we'd like to be able to check this before then. */
6971 if (COMPLETE_TYPE_P (type) && is_empty_class (type))
6974 for (binfo = TYPE_BINFO (type), i = 0;
6975 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6976 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
6978 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
6979 if (TREE_CODE (field) == FIELD_DECL
6980 && !DECL_ARTIFICIAL (field)
6981 && !is_really_empty_class (TREE_TYPE (field)))
6985 else if (TREE_CODE (type) == ARRAY_TYPE)
6986 return is_really_empty_class (TREE_TYPE (type));
6990 /* Note that NAME was looked up while the current class was being
6991 defined and that the result of that lookup was DECL. */
6994 maybe_note_name_used_in_class (tree name, tree decl)
6996 splay_tree names_used;
6998 /* If we're not defining a class, there's nothing to do. */
6999 if (!(innermost_scope_kind() == sk_class
7000 && TYPE_BEING_DEFINED (current_class_type)
7001 && !LAMBDA_TYPE_P (current_class_type)))
7004 /* If there's already a binding for this NAME, then we don't have
7005 anything to worry about. */
7006 if (lookup_member (current_class_type, name,
7007 /*protect=*/0, /*want_type=*/false))
7010 if (!current_class_stack[current_class_depth - 1].names_used)
7011 current_class_stack[current_class_depth - 1].names_used
7012 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
7013 names_used = current_class_stack[current_class_depth - 1].names_used;
7015 splay_tree_insert (names_used,
7016 (splay_tree_key) name,
7017 (splay_tree_value) decl);
7020 /* Note that NAME was declared (as DECL) in the current class. Check
7021 to see that the declaration is valid. */
7024 note_name_declared_in_class (tree name, tree decl)
7026 splay_tree names_used;
7029 /* Look to see if we ever used this name. */
7031 = current_class_stack[current_class_depth - 1].names_used;
7034 /* The C language allows members to be declared with a type of the same
7035 name, and the C++ standard says this diagnostic is not required. So
7036 allow it in extern "C" blocks unless predantic is specified.
7037 Allow it in all cases if -ms-extensions is specified. */
7038 if ((!pedantic && current_lang_name == lang_name_c)
7039 || flag_ms_extensions)
7041 n = splay_tree_lookup (names_used, (splay_tree_key) name);
7044 /* [basic.scope.class]
7046 A name N used in a class S shall refer to the same declaration
7047 in its context and when re-evaluated in the completed scope of
7049 permerror (input_location, "declaration of %q#D", decl);
7050 permerror (input_location, "changes meaning of %qD from %q+#D",
7051 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
7055 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
7056 Secondary vtables are merged with primary vtables; this function
7057 will return the VAR_DECL for the primary vtable. */
7060 get_vtbl_decl_for_binfo (tree binfo)
7064 decl = BINFO_VTABLE (binfo);
7065 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
7067 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
7068 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
7071 gcc_assert (TREE_CODE (decl) == VAR_DECL);
7076 /* Returns the binfo for the primary base of BINFO. If the resulting
7077 BINFO is a virtual base, and it is inherited elsewhere in the
7078 hierarchy, then the returned binfo might not be the primary base of
7079 BINFO in the complete object. Check BINFO_PRIMARY_P or
7080 BINFO_LOST_PRIMARY_P to be sure. */
7083 get_primary_binfo (tree binfo)
7087 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
7091 return copied_binfo (primary_base, binfo);
7094 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
7097 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
7100 fprintf (stream, "%*s", indent, "");
7104 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
7105 INDENT should be zero when called from the top level; it is
7106 incremented recursively. IGO indicates the next expected BINFO in
7107 inheritance graph ordering. */
7110 dump_class_hierarchy_r (FILE *stream,
7120 indented = maybe_indent_hierarchy (stream, indent, 0);
7121 fprintf (stream, "%s (0x%lx) ",
7122 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
7123 (unsigned long) binfo);
7126 fprintf (stream, "alternative-path\n");
7129 igo = TREE_CHAIN (binfo);
7131 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
7132 tree_low_cst (BINFO_OFFSET (binfo), 0));
7133 if (is_empty_class (BINFO_TYPE (binfo)))
7134 fprintf (stream, " empty");
7135 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
7136 fprintf (stream, " nearly-empty");
7137 if (BINFO_VIRTUAL_P (binfo))
7138 fprintf (stream, " virtual");
7139 fprintf (stream, "\n");
7142 if (BINFO_PRIMARY_P (binfo))
7144 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7145 fprintf (stream, " primary-for %s (0x%lx)",
7146 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
7147 TFF_PLAIN_IDENTIFIER),
7148 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
7150 if (BINFO_LOST_PRIMARY_P (binfo))
7152 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7153 fprintf (stream, " lost-primary");
7156 fprintf (stream, "\n");
7158 if (!(flags & TDF_SLIM))
7162 if (BINFO_SUBVTT_INDEX (binfo))
7164 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7165 fprintf (stream, " subvttidx=%s",
7166 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
7167 TFF_PLAIN_IDENTIFIER));
7169 if (BINFO_VPTR_INDEX (binfo))
7171 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7172 fprintf (stream, " vptridx=%s",
7173 expr_as_string (BINFO_VPTR_INDEX (binfo),
7174 TFF_PLAIN_IDENTIFIER));
7176 if (BINFO_VPTR_FIELD (binfo))
7178 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7179 fprintf (stream, " vbaseoffset=%s",
7180 expr_as_string (BINFO_VPTR_FIELD (binfo),
7181 TFF_PLAIN_IDENTIFIER));
7183 if (BINFO_VTABLE (binfo))
7185 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7186 fprintf (stream, " vptr=%s",
7187 expr_as_string (BINFO_VTABLE (binfo),
7188 TFF_PLAIN_IDENTIFIER));
7192 fprintf (stream, "\n");
7195 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
7196 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
7201 /* Dump the BINFO hierarchy for T. */
7204 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
7206 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7207 fprintf (stream, " size=%lu align=%lu\n",
7208 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
7209 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
7210 fprintf (stream, " base size=%lu base align=%lu\n",
7211 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
7213 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
7215 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
7216 fprintf (stream, "\n");
7219 /* Debug interface to hierarchy dumping. */
7222 debug_class (tree t)
7224 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
7228 dump_class_hierarchy (tree t)
7231 FILE *stream = dump_begin (TDI_class, &flags);
7235 dump_class_hierarchy_1 (stream, flags, t);
7236 dump_end (TDI_class, stream);
7241 dump_array (FILE * stream, tree decl)
7244 unsigned HOST_WIDE_INT ix;
7246 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
7248 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
7250 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
7251 fprintf (stream, " %s entries",
7252 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
7253 TFF_PLAIN_IDENTIFIER));
7254 fprintf (stream, "\n");
7256 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
7258 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
7259 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
7263 dump_vtable (tree t, tree binfo, tree vtable)
7266 FILE *stream = dump_begin (TDI_class, &flags);
7271 if (!(flags & TDF_SLIM))
7273 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
7275 fprintf (stream, "%s for %s",
7276 ctor_vtbl_p ? "Construction vtable" : "Vtable",
7277 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
7280 if (!BINFO_VIRTUAL_P (binfo))
7281 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
7282 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7284 fprintf (stream, "\n");
7285 dump_array (stream, vtable);
7286 fprintf (stream, "\n");
7289 dump_end (TDI_class, stream);
7293 dump_vtt (tree t, tree vtt)
7296 FILE *stream = dump_begin (TDI_class, &flags);
7301 if (!(flags & TDF_SLIM))
7303 fprintf (stream, "VTT for %s\n",
7304 type_as_string (t, TFF_PLAIN_IDENTIFIER));
7305 dump_array (stream, vtt);
7306 fprintf (stream, "\n");
7309 dump_end (TDI_class, stream);
7312 /* Dump a function or thunk and its thunkees. */
7315 dump_thunk (FILE *stream, int indent, tree thunk)
7317 static const char spaces[] = " ";
7318 tree name = DECL_NAME (thunk);
7321 fprintf (stream, "%.*s%p %s %s", indent, spaces,
7323 !DECL_THUNK_P (thunk) ? "function"
7324 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
7325 name ? IDENTIFIER_POINTER (name) : "<unset>");
7326 if (DECL_THUNK_P (thunk))
7328 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
7329 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
7331 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
7332 if (!virtual_adjust)
7334 else if (DECL_THIS_THUNK_P (thunk))
7335 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
7336 tree_low_cst (virtual_adjust, 0));
7338 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
7339 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
7340 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
7341 if (THUNK_ALIAS (thunk))
7342 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
7344 fprintf (stream, "\n");
7345 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
7346 dump_thunk (stream, indent + 2, thunks);
7349 /* Dump the thunks for FN. */
7352 debug_thunks (tree fn)
7354 dump_thunk (stderr, 0, fn);
7357 /* Virtual function table initialization. */
7359 /* Create all the necessary vtables for T and its base classes. */
7362 finish_vtbls (tree t)
7365 VEC(constructor_elt,gc) *v = NULL;
7366 tree vtable = BINFO_VTABLE (TYPE_BINFO (t));
7368 /* We lay out the primary and secondary vtables in one contiguous
7369 vtable. The primary vtable is first, followed by the non-virtual
7370 secondary vtables in inheritance graph order. */
7371 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t),
7374 /* Then come the virtual bases, also in inheritance graph order. */
7375 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
7377 if (!BINFO_VIRTUAL_P (vbase))
7379 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), vtable, t, &v);
7382 if (BINFO_VTABLE (TYPE_BINFO (t)))
7383 initialize_vtable (TYPE_BINFO (t), v);
7386 /* Initialize the vtable for BINFO with the INITS. */
7389 initialize_vtable (tree binfo, VEC(constructor_elt,gc) *inits)
7393 layout_vtable_decl (binfo, VEC_length (constructor_elt, inits));
7394 decl = get_vtbl_decl_for_binfo (binfo);
7395 initialize_artificial_var (decl, inits);
7396 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
7399 /* Build the VTT (virtual table table) for T.
7400 A class requires a VTT if it has virtual bases.
7403 1 - primary virtual pointer for complete object T
7404 2 - secondary VTTs for each direct non-virtual base of T which requires a
7406 3 - secondary virtual pointers for each direct or indirect base of T which
7407 has virtual bases or is reachable via a virtual path from T.
7408 4 - secondary VTTs for each direct or indirect virtual base of T.
7410 Secondary VTTs look like complete object VTTs without part 4. */
7418 VEC(constructor_elt,gc) *inits;
7420 /* Build up the initializers for the VTT. */
7422 index = size_zero_node;
7423 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7425 /* If we didn't need a VTT, we're done. */
7429 /* Figure out the type of the VTT. */
7430 type = build_array_of_n_type (const_ptr_type_node,
7431 VEC_length (constructor_elt, inits));
7433 /* Now, build the VTT object itself. */
7434 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7435 initialize_artificial_var (vtt, inits);
7436 /* Add the VTT to the vtables list. */
7437 DECL_CHAIN (vtt) = DECL_CHAIN (CLASSTYPE_VTABLES (t));
7438 DECL_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7443 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7444 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7445 and CHAIN the vtable pointer for this binfo after construction is
7446 complete. VALUE can also be another BINFO, in which case we recurse. */
7449 binfo_ctor_vtable (tree binfo)
7455 vt = BINFO_VTABLE (binfo);
7456 if (TREE_CODE (vt) == TREE_LIST)
7457 vt = TREE_VALUE (vt);
7458 if (TREE_CODE (vt) == TREE_BINFO)
7467 /* Data for secondary VTT initialization. */
7468 typedef struct secondary_vptr_vtt_init_data_s
7470 /* Is this the primary VTT? */
7473 /* Current index into the VTT. */
7476 /* Vector of initializers built up. */
7477 VEC(constructor_elt,gc) *inits;
7479 /* The type being constructed by this secondary VTT. */
7480 tree type_being_constructed;
7481 } secondary_vptr_vtt_init_data;
7483 /* Recursively build the VTT-initializer for BINFO (which is in the
7484 hierarchy dominated by T). INITS points to the end of the initializer
7485 list to date. INDEX is the VTT index where the next element will be
7486 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7487 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7488 for virtual bases of T. When it is not so, we build the constructor
7489 vtables for the BINFO-in-T variant. */
7492 build_vtt_inits (tree binfo, tree t, VEC(constructor_elt,gc) **inits, tree *index)
7497 secondary_vptr_vtt_init_data data;
7498 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7500 /* We only need VTTs for subobjects with virtual bases. */
7501 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7504 /* We need to use a construction vtable if this is not the primary
7508 build_ctor_vtbl_group (binfo, t);
7510 /* Record the offset in the VTT where this sub-VTT can be found. */
7511 BINFO_SUBVTT_INDEX (binfo) = *index;
7514 /* Add the address of the primary vtable for the complete object. */
7515 init = binfo_ctor_vtable (binfo);
7516 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7519 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7520 BINFO_VPTR_INDEX (binfo) = *index;
7522 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7524 /* Recursively add the secondary VTTs for non-virtual bases. */
7525 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7526 if (!BINFO_VIRTUAL_P (b))
7527 build_vtt_inits (b, t, inits, index);
7529 /* Add secondary virtual pointers for all subobjects of BINFO with
7530 either virtual bases or reachable along a virtual path, except
7531 subobjects that are non-virtual primary bases. */
7532 data.top_level_p = top_level_p;
7533 data.index = *index;
7534 data.inits = *inits;
7535 data.type_being_constructed = BINFO_TYPE (binfo);
7537 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7539 *index = data.index;
7541 /* data.inits might have grown as we added secondary virtual pointers.
7542 Make sure our caller knows about the new vector. */
7543 *inits = data.inits;
7546 /* Add the secondary VTTs for virtual bases in inheritance graph
7548 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7550 if (!BINFO_VIRTUAL_P (b))
7553 build_vtt_inits (b, t, inits, index);
7556 /* Remove the ctor vtables we created. */
7557 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7560 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7561 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7564 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7566 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7568 /* We don't care about bases that don't have vtables. */
7569 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7570 return dfs_skip_bases;
7572 /* We're only interested in proper subobjects of the type being
7574 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7577 /* We're only interested in bases with virtual bases or reachable
7578 via a virtual path from the type being constructed. */
7579 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7580 || binfo_via_virtual (binfo, data->type_being_constructed)))
7581 return dfs_skip_bases;
7583 /* We're not interested in non-virtual primary bases. */
7584 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7587 /* Record the index where this secondary vptr can be found. */
7588 if (data->top_level_p)
7590 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7591 BINFO_VPTR_INDEX (binfo) = data->index;
7593 if (BINFO_VIRTUAL_P (binfo))
7595 /* It's a primary virtual base, and this is not a
7596 construction vtable. Find the base this is primary of in
7597 the inheritance graph, and use that base's vtable
7599 while (BINFO_PRIMARY_P (binfo))
7600 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7604 /* Add the initializer for the secondary vptr itself. */
7605 CONSTRUCTOR_APPEND_ELT (data->inits, NULL_TREE, binfo_ctor_vtable (binfo));
7607 /* Advance the vtt index. */
7608 data->index = size_binop (PLUS_EXPR, data->index,
7609 TYPE_SIZE_UNIT (ptr_type_node));
7614 /* Called from build_vtt_inits via dfs_walk. After building
7615 constructor vtables and generating the sub-vtt from them, we need
7616 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7617 binfo of the base whose sub vtt was generated. */
7620 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7622 tree vtable = BINFO_VTABLE (binfo);
7624 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7625 /* If this class has no vtable, none of its bases do. */
7626 return dfs_skip_bases;
7629 /* This might be a primary base, so have no vtable in this
7633 /* If we scribbled the construction vtable vptr into BINFO, clear it
7635 if (TREE_CODE (vtable) == TREE_LIST
7636 && (TREE_PURPOSE (vtable) == (tree) data))
7637 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7642 /* Build the construction vtable group for BINFO which is in the
7643 hierarchy dominated by T. */
7646 build_ctor_vtbl_group (tree binfo, tree t)
7652 VEC(constructor_elt,gc) *v;
7654 /* See if we've already created this construction vtable group. */
7655 id = mangle_ctor_vtbl_for_type (t, binfo);
7656 if (IDENTIFIER_GLOBAL_VALUE (id))
7659 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7660 /* Build a version of VTBL (with the wrong type) for use in
7661 constructing the addresses of secondary vtables in the
7662 construction vtable group. */
7663 vtbl = build_vtable (t, id, ptr_type_node);
7664 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7667 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7668 binfo, vtbl, t, &v);
7670 /* Add the vtables for each of our virtual bases using the vbase in T
7672 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7674 vbase = TREE_CHAIN (vbase))
7678 if (!BINFO_VIRTUAL_P (vbase))
7680 b = copied_binfo (vbase, binfo);
7682 accumulate_vtbl_inits (b, vbase, binfo, vtbl, t, &v);
7685 /* Figure out the type of the construction vtable. */
7686 type = build_array_of_n_type (vtable_entry_type,
7687 VEC_length (constructor_elt, v));
7689 TREE_TYPE (vtbl) = type;
7690 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7691 layout_decl (vtbl, 0);
7693 /* Initialize the construction vtable. */
7694 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7695 initialize_artificial_var (vtbl, v);
7696 dump_vtable (t, binfo, vtbl);
7699 /* Add the vtbl initializers for BINFO (and its bases other than
7700 non-virtual primaries) to the list of INITS. BINFO is in the
7701 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7702 the constructor the vtbl inits should be accumulated for. (If this
7703 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7704 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7705 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7706 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7707 but are not necessarily the same in terms of layout. */
7710 accumulate_vtbl_inits (tree binfo,
7715 VEC(constructor_elt,gc) **inits)
7719 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7721 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7723 /* If it doesn't have a vptr, we don't do anything. */
7724 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7727 /* If we're building a construction vtable, we're not interested in
7728 subobjects that don't require construction vtables. */
7730 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7731 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7734 /* Build the initializers for the BINFO-in-T vtable. */
7735 dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, vtbl, t, inits);
7737 /* Walk the BINFO and its bases. We walk in preorder so that as we
7738 initialize each vtable we can figure out at what offset the
7739 secondary vtable lies from the primary vtable. We can't use
7740 dfs_walk here because we need to iterate through bases of BINFO
7741 and RTTI_BINFO simultaneously. */
7742 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7744 /* Skip virtual bases. */
7745 if (BINFO_VIRTUAL_P (base_binfo))
7747 accumulate_vtbl_inits (base_binfo,
7748 BINFO_BASE_BINFO (orig_binfo, i),
7749 rtti_binfo, vtbl, t,
7754 /* Called from accumulate_vtbl_inits. Adds the initializers for the
7755 BINFO vtable to L. */
7758 dfs_accumulate_vtbl_inits (tree binfo,
7763 VEC(constructor_elt,gc) **l)
7765 tree vtbl = NULL_TREE;
7766 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7770 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7772 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7773 primary virtual base. If it is not the same primary in
7774 the hierarchy of T, we'll need to generate a ctor vtable
7775 for it, to place at its location in T. If it is the same
7776 primary, we still need a VTT entry for the vtable, but it
7777 should point to the ctor vtable for the base it is a
7778 primary for within the sub-hierarchy of RTTI_BINFO.
7780 There are three possible cases:
7782 1) We are in the same place.
7783 2) We are a primary base within a lost primary virtual base of
7785 3) We are primary to something not a base of RTTI_BINFO. */
7788 tree last = NULL_TREE;
7790 /* First, look through the bases we are primary to for RTTI_BINFO
7791 or a virtual base. */
7793 while (BINFO_PRIMARY_P (b))
7795 b = BINFO_INHERITANCE_CHAIN (b);
7797 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7800 /* If we run out of primary links, keep looking down our
7801 inheritance chain; we might be an indirect primary. */
7802 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7803 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7807 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7808 base B and it is a base of RTTI_BINFO, this is case 2. In
7809 either case, we share our vtable with LAST, i.e. the
7810 derived-most base within B of which we are a primary. */
7812 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7813 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7814 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7815 binfo_ctor_vtable after everything's been set up. */
7818 /* Otherwise, this is case 3 and we get our own. */
7820 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7823 n_inits = VEC_length (constructor_elt, *l);
7830 /* Add the initializer for this vtable. */
7831 build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7832 &non_fn_entries, l);
7834 /* Figure out the position to which the VPTR should point. */
7835 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, orig_vtbl);
7836 index = size_binop (PLUS_EXPR,
7837 size_int (non_fn_entries),
7838 size_int (n_inits));
7839 index = size_binop (MULT_EXPR,
7840 TYPE_SIZE_UNIT (vtable_entry_type),
7842 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7846 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7847 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7848 straighten this out. */
7849 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7850 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7851 /* Throw away any unneeded intializers. */
7852 VEC_truncate (constructor_elt, *l, n_inits);
7854 /* For an ordinary vtable, set BINFO_VTABLE. */
7855 BINFO_VTABLE (binfo) = vtbl;
7858 static GTY(()) tree abort_fndecl_addr;
7860 /* Construct the initializer for BINFO's virtual function table. BINFO
7861 is part of the hierarchy dominated by T. If we're building a
7862 construction vtable, the ORIG_BINFO is the binfo we should use to
7863 find the actual function pointers to put in the vtable - but they
7864 can be overridden on the path to most-derived in the graph that
7865 ORIG_BINFO belongs. Otherwise,
7866 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7867 BINFO that should be indicated by the RTTI information in the
7868 vtable; it will be a base class of T, rather than T itself, if we
7869 are building a construction vtable.
7871 The value returned is a TREE_LIST suitable for wrapping in a
7872 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7873 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7874 number of non-function entries in the vtable.
7876 It might seem that this function should never be called with a
7877 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7878 base is always subsumed by a derived class vtable. However, when
7879 we are building construction vtables, we do build vtables for
7880 primary bases; we need these while the primary base is being
7884 build_vtbl_initializer (tree binfo,
7888 int* non_fn_entries_p,
7889 VEC(constructor_elt,gc) **inits)
7895 VEC(tree,gc) *vbases;
7898 /* Initialize VID. */
7899 memset (&vid, 0, sizeof (vid));
7902 vid.rtti_binfo = rtti_binfo;
7903 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7904 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7905 vid.generate_vcall_entries = true;
7906 /* The first vbase or vcall offset is at index -3 in the vtable. */
7907 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7909 /* Add entries to the vtable for RTTI. */
7910 build_rtti_vtbl_entries (binfo, &vid);
7912 /* Create an array for keeping track of the functions we've
7913 processed. When we see multiple functions with the same
7914 signature, we share the vcall offsets. */
7915 vid.fns = VEC_alloc (tree, gc, 32);
7916 /* Add the vcall and vbase offset entries. */
7917 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7919 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7920 build_vbase_offset_vtbl_entries. */
7921 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7922 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7923 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7925 /* If the target requires padding between data entries, add that now. */
7926 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7928 int n_entries = VEC_length (constructor_elt, vid.inits);
7930 VEC_safe_grow (constructor_elt, gc, vid.inits,
7931 TARGET_VTABLE_DATA_ENTRY_DISTANCE * n_entries);
7933 /* Move data entries into their new positions and add padding
7934 after the new positions. Iterate backwards so we don't
7935 overwrite entries that we would need to process later. */
7936 for (ix = n_entries - 1;
7937 VEC_iterate (constructor_elt, vid.inits, ix, e);
7941 int new_position = (TARGET_VTABLE_DATA_ENTRY_DISTANCE * ix
7942 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE - 1));
7944 VEC_replace (constructor_elt, vid.inits, new_position, e);
7946 for (j = 1; j < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++j)
7948 constructor_elt *f = VEC_index (constructor_elt, vid.inits,
7950 f->index = NULL_TREE;
7951 f->value = build1 (NOP_EXPR, vtable_entry_type,
7957 if (non_fn_entries_p)
7958 *non_fn_entries_p = VEC_length (constructor_elt, vid.inits);
7960 /* The initializers for virtual functions were built up in reverse
7961 order. Straighten them out and add them to the running list in one
7963 jx = VEC_length (constructor_elt, *inits);
7964 VEC_safe_grow (constructor_elt, gc, *inits,
7965 (jx + VEC_length (constructor_elt, vid.inits)));
7967 for (ix = VEC_length (constructor_elt, vid.inits) - 1;
7968 VEC_iterate (constructor_elt, vid.inits, ix, e);
7970 VEC_replace (constructor_elt, *inits, jx, e);
7972 /* Go through all the ordinary virtual functions, building up
7974 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7978 tree fn, fn_original;
7979 tree init = NULL_TREE;
7983 if (DECL_THUNK_P (fn))
7985 if (!DECL_NAME (fn))
7987 if (THUNK_ALIAS (fn))
7989 fn = THUNK_ALIAS (fn);
7992 fn_original = THUNK_TARGET (fn);
7995 /* If the only definition of this function signature along our
7996 primary base chain is from a lost primary, this vtable slot will
7997 never be used, so just zero it out. This is important to avoid
7998 requiring extra thunks which cannot be generated with the function.
8000 We first check this in update_vtable_entry_for_fn, so we handle
8001 restored primary bases properly; we also need to do it here so we
8002 zero out unused slots in ctor vtables, rather than filling them
8003 with erroneous values (though harmless, apart from relocation
8005 if (BV_LOST_PRIMARY (v))
8006 init = size_zero_node;
8010 /* Pull the offset for `this', and the function to call, out of
8012 delta = BV_DELTA (v);
8013 vcall_index = BV_VCALL_INDEX (v);
8015 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
8016 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
8018 /* You can't call an abstract virtual function; it's abstract.
8019 So, we replace these functions with __pure_virtual. */
8020 if (DECL_PURE_VIRTUAL_P (fn_original))
8023 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8025 if (abort_fndecl_addr == NULL)
8027 = fold_convert (vfunc_ptr_type_node,
8028 build_fold_addr_expr (fn));
8029 init = abort_fndecl_addr;
8034 if (!integer_zerop (delta) || vcall_index)
8036 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
8037 if (!DECL_NAME (fn))
8040 /* Take the address of the function, considering it to be of an
8041 appropriate generic type. */
8042 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8043 init = fold_convert (vfunc_ptr_type_node,
8044 build_fold_addr_expr (fn));
8048 /* And add it to the chain of initializers. */
8049 if (TARGET_VTABLE_USES_DESCRIPTORS)
8052 if (init == size_zero_node)
8053 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8054 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8056 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8058 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
8059 fn, build_int_cst (NULL_TREE, i));
8060 TREE_CONSTANT (fdesc) = 1;
8062 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, fdesc);
8066 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8070 /* Adds to vid->inits the initializers for the vbase and vcall
8071 offsets in BINFO, which is in the hierarchy dominated by T. */
8074 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
8078 /* If this is a derived class, we must first create entries
8079 corresponding to the primary base class. */
8080 b = get_primary_binfo (binfo);
8082 build_vcall_and_vbase_vtbl_entries (b, vid);
8084 /* Add the vbase entries for this base. */
8085 build_vbase_offset_vtbl_entries (binfo, vid);
8086 /* Add the vcall entries for this base. */
8087 build_vcall_offset_vtbl_entries (binfo, vid);
8090 /* Returns the initializers for the vbase offset entries in the vtable
8091 for BINFO (which is part of the class hierarchy dominated by T), in
8092 reverse order. VBASE_OFFSET_INDEX gives the vtable index
8093 where the next vbase offset will go. */
8096 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8100 tree non_primary_binfo;
8102 /* If there are no virtual baseclasses, then there is nothing to
8104 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
8109 /* We might be a primary base class. Go up the inheritance hierarchy
8110 until we find the most derived class of which we are a primary base:
8111 it is the offset of that which we need to use. */
8112 non_primary_binfo = binfo;
8113 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8117 /* If we have reached a virtual base, then it must be a primary
8118 base (possibly multi-level) of vid->binfo, or we wouldn't
8119 have called build_vcall_and_vbase_vtbl_entries for it. But it
8120 might be a lost primary, so just skip down to vid->binfo. */
8121 if (BINFO_VIRTUAL_P (non_primary_binfo))
8123 non_primary_binfo = vid->binfo;
8127 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8128 if (get_primary_binfo (b) != non_primary_binfo)
8130 non_primary_binfo = b;
8133 /* Go through the virtual bases, adding the offsets. */
8134 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
8136 vbase = TREE_CHAIN (vbase))
8141 if (!BINFO_VIRTUAL_P (vbase))
8144 /* Find the instance of this virtual base in the complete
8146 b = copied_binfo (vbase, binfo);
8148 /* If we've already got an offset for this virtual base, we
8149 don't need another one. */
8150 if (BINFO_VTABLE_PATH_MARKED (b))
8152 BINFO_VTABLE_PATH_MARKED (b) = 1;
8154 /* Figure out where we can find this vbase offset. */
8155 delta = size_binop (MULT_EXPR,
8158 TYPE_SIZE_UNIT (vtable_entry_type)));
8159 if (vid->primary_vtbl_p)
8160 BINFO_VPTR_FIELD (b) = delta;
8162 if (binfo != TYPE_BINFO (t))
8163 /* The vbase offset had better be the same. */
8164 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
8166 /* The next vbase will come at a more negative offset. */
8167 vid->index = size_binop (MINUS_EXPR, vid->index,
8168 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8170 /* The initializer is the delta from BINFO to this virtual base.
8171 The vbase offsets go in reverse inheritance-graph order, and
8172 we are walking in inheritance graph order so these end up in
8174 delta = size_diffop_loc (input_location,
8175 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
8177 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE,
8178 fold_build1_loc (input_location, NOP_EXPR,
8179 vtable_entry_type, delta));
8183 /* Adds the initializers for the vcall offset entries in the vtable
8184 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
8188 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8190 /* We only need these entries if this base is a virtual base. We
8191 compute the indices -- but do not add to the vtable -- when
8192 building the main vtable for a class. */
8193 if (binfo == TYPE_BINFO (vid->derived)
8194 || (BINFO_VIRTUAL_P (binfo)
8195 /* If BINFO is RTTI_BINFO, then (since BINFO does not
8196 correspond to VID->DERIVED), we are building a primary
8197 construction virtual table. Since this is a primary
8198 virtual table, we do not need the vcall offsets for
8200 && binfo != vid->rtti_binfo))
8202 /* We need a vcall offset for each of the virtual functions in this
8203 vtable. For example:
8205 class A { virtual void f (); };
8206 class B1 : virtual public A { virtual void f (); };
8207 class B2 : virtual public A { virtual void f (); };
8208 class C: public B1, public B2 { virtual void f (); };
8210 A C object has a primary base of B1, which has a primary base of A. A
8211 C also has a secondary base of B2, which no longer has a primary base
8212 of A. So the B2-in-C construction vtable needs a secondary vtable for
8213 A, which will adjust the A* to a B2* to call f. We have no way of
8214 knowing what (or even whether) this offset will be when we define B2,
8215 so we store this "vcall offset" in the A sub-vtable and look it up in
8216 a "virtual thunk" for B2::f.
8218 We need entries for all the functions in our primary vtable and
8219 in our non-virtual bases' secondary vtables. */
8221 /* If we are just computing the vcall indices -- but do not need
8222 the actual entries -- not that. */
8223 if (!BINFO_VIRTUAL_P (binfo))
8224 vid->generate_vcall_entries = false;
8225 /* Now, walk through the non-virtual bases, adding vcall offsets. */
8226 add_vcall_offset_vtbl_entries_r (binfo, vid);
8230 /* Build vcall offsets, starting with those for BINFO. */
8233 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
8239 /* Don't walk into virtual bases -- except, of course, for the
8240 virtual base for which we are building vcall offsets. Any
8241 primary virtual base will have already had its offsets generated
8242 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8243 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
8246 /* If BINFO has a primary base, process it first. */
8247 primary_binfo = get_primary_binfo (binfo);
8249 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
8251 /* Add BINFO itself to the list. */
8252 add_vcall_offset_vtbl_entries_1 (binfo, vid);
8254 /* Scan the non-primary bases of BINFO. */
8255 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8256 if (base_binfo != primary_binfo)
8257 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
8260 /* Called from build_vcall_offset_vtbl_entries_r. */
8263 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
8265 /* Make entries for the rest of the virtuals. */
8266 if (abi_version_at_least (2))
8270 /* The ABI requires that the methods be processed in declaration
8271 order. G++ 3.2 used the order in the vtable. */
8272 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
8274 orig_fn = DECL_CHAIN (orig_fn))
8275 if (DECL_VINDEX (orig_fn))
8276 add_vcall_offset (orig_fn, binfo, vid);
8280 tree derived_virtuals;
8283 /* If BINFO is a primary base, the most derived class which has
8284 BINFO as a primary base; otherwise, just BINFO. */
8285 tree non_primary_binfo;
8287 /* We might be a primary base class. Go up the inheritance hierarchy
8288 until we find the most derived class of which we are a primary base:
8289 it is the BINFO_VIRTUALS there that we need to consider. */
8290 non_primary_binfo = binfo;
8291 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8295 /* If we have reached a virtual base, then it must be vid->vbase,
8296 because we ignore other virtual bases in
8297 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8298 base (possibly multi-level) of vid->binfo, or we wouldn't
8299 have called build_vcall_and_vbase_vtbl_entries for it. But it
8300 might be a lost primary, so just skip down to vid->binfo. */
8301 if (BINFO_VIRTUAL_P (non_primary_binfo))
8303 gcc_assert (non_primary_binfo == vid->vbase);
8304 non_primary_binfo = vid->binfo;
8308 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8309 if (get_primary_binfo (b) != non_primary_binfo)
8311 non_primary_binfo = b;
8314 if (vid->ctor_vtbl_p)
8315 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8316 where rtti_binfo is the most derived type. */
8318 = original_binfo (non_primary_binfo, vid->rtti_binfo);
8320 for (base_virtuals = BINFO_VIRTUALS (binfo),
8321 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
8322 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
8324 base_virtuals = TREE_CHAIN (base_virtuals),
8325 derived_virtuals = TREE_CHAIN (derived_virtuals),
8326 orig_virtuals = TREE_CHAIN (orig_virtuals))
8330 /* Find the declaration that originally caused this function to
8331 be present in BINFO_TYPE (binfo). */
8332 orig_fn = BV_FN (orig_virtuals);
8334 /* When processing BINFO, we only want to generate vcall slots for
8335 function slots introduced in BINFO. So don't try to generate
8336 one if the function isn't even defined in BINFO. */
8337 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
8340 add_vcall_offset (orig_fn, binfo, vid);
8345 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8348 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
8354 /* If there is already an entry for a function with the same
8355 signature as FN, then we do not need a second vcall offset.
8356 Check the list of functions already present in the derived
8358 FOR_EACH_VEC_ELT (tree, vid->fns, i, derived_entry)
8360 if (same_signature_p (derived_entry, orig_fn)
8361 /* We only use one vcall offset for virtual destructors,
8362 even though there are two virtual table entries. */
8363 || (DECL_DESTRUCTOR_P (derived_entry)
8364 && DECL_DESTRUCTOR_P (orig_fn)))
8368 /* If we are building these vcall offsets as part of building
8369 the vtable for the most derived class, remember the vcall
8371 if (vid->binfo == TYPE_BINFO (vid->derived))
8373 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
8374 CLASSTYPE_VCALL_INDICES (vid->derived),
8376 elt->purpose = orig_fn;
8377 elt->value = vid->index;
8380 /* The next vcall offset will be found at a more negative
8382 vid->index = size_binop (MINUS_EXPR, vid->index,
8383 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8385 /* Keep track of this function. */
8386 VEC_safe_push (tree, gc, vid->fns, orig_fn);
8388 if (vid->generate_vcall_entries)
8393 /* Find the overriding function. */
8394 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8395 if (fn == error_mark_node)
8396 vcall_offset = build_zero_cst (vtable_entry_type);
8399 base = TREE_VALUE (fn);
8401 /* The vbase we're working on is a primary base of
8402 vid->binfo. But it might be a lost primary, so its
8403 BINFO_OFFSET might be wrong, so we just use the
8404 BINFO_OFFSET from vid->binfo. */
8405 vcall_offset = size_diffop_loc (input_location,
8406 BINFO_OFFSET (base),
8407 BINFO_OFFSET (vid->binfo));
8408 vcall_offset = fold_build1_loc (input_location,
8409 NOP_EXPR, vtable_entry_type,
8412 /* Add the initializer to the vtable. */
8413 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, vcall_offset);
8417 /* Return vtbl initializers for the RTTI entries corresponding to the
8418 BINFO's vtable. The RTTI entries should indicate the object given
8419 by VID->rtti_binfo. */
8422 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8430 t = BINFO_TYPE (vid->rtti_binfo);
8432 /* To find the complete object, we will first convert to our most
8433 primary base, and then add the offset in the vtbl to that value. */
8435 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8436 && !BINFO_LOST_PRIMARY_P (b))
8440 primary_base = get_primary_binfo (b);
8441 gcc_assert (BINFO_PRIMARY_P (primary_base)
8442 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8445 offset = size_diffop_loc (input_location,
8446 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8448 /* The second entry is the address of the typeinfo object. */
8450 decl = build_address (get_tinfo_decl (t));
8452 decl = integer_zero_node;
8454 /* Convert the declaration to a type that can be stored in the
8456 init = build_nop (vfunc_ptr_type_node, decl);
8457 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8459 /* Add the offset-to-top entry. It comes earlier in the vtable than
8460 the typeinfo entry. Convert the offset to look like a
8461 function pointer, so that we can put it in the vtable. */
8462 init = build_nop (vfunc_ptr_type_node, offset);
8463 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8466 #include "gt-cp-class.h"