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
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
39 #include "tree-dump.h"
41 /* The number of nested classes being processed. If we are not in the
42 scope of any class, this is zero. */
44 int current_class_depth;
46 /* In order to deal with nested classes, we keep a stack of classes.
47 The topmost entry is the innermost class, and is the entry at index
48 CURRENT_CLASS_DEPTH */
50 typedef struct class_stack_node {
51 /* The name of the class. */
54 /* The _TYPE node for the class. */
57 /* The access specifier pending for new declarations in the scope of
61 /* If were defining TYPE, the names used in this class. */
62 splay_tree names_used;
64 /* Nonzero if this class is no longer open, because of a call to
67 }* class_stack_node_t;
69 typedef struct vtbl_init_data_s
71 /* The base for which we're building initializers. */
73 /* The type of the most-derived type. */
75 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
76 unless ctor_vtbl_p is true. */
78 /* The negative-index vtable initializers built up so far. These
79 are in order from least negative index to most negative index. */
81 /* The last (i.e., most negative) entry in INITS. */
83 /* The binfo for the virtual base for which we're building
84 vcall offset initializers. */
86 /* The functions in vbase for which we have already provided vcall
89 /* The vtable index of the next vcall or vbase offset. */
91 /* Nonzero if we are building the initializer for the primary
94 /* Nonzero if we are building the initializer for a construction
97 /* True when adding vcall offset entries to the vtable. False when
98 merely computing the indices. */
99 bool generate_vcall_entries;
102 /* The type of a function passed to walk_subobject_offsets. */
103 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
105 /* The stack itself. This is a dynamically resized array. The
106 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
107 static int current_class_stack_size;
108 static class_stack_node_t current_class_stack;
110 /* The size of the largest empty class seen in this translation unit. */
111 static GTY (()) tree sizeof_biggest_empty_class;
113 /* An array of all local classes present in this translation unit, in
114 declaration order. */
115 VEC(tree,gc) *local_classes;
117 static tree get_vfield_name (tree);
118 static void finish_struct_anon (tree);
119 static tree get_vtable_name (tree);
120 static tree get_basefndecls (tree, tree);
121 static int build_primary_vtable (tree, tree);
122 static int build_secondary_vtable (tree);
123 static void finish_vtbls (tree);
124 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
125 static void finish_struct_bits (tree);
126 static int alter_access (tree, tree, tree);
127 static void handle_using_decl (tree, tree);
128 static tree dfs_modify_vtables (tree, void *);
129 static tree modify_all_vtables (tree, tree);
130 static void determine_primary_bases (tree);
131 static void finish_struct_methods (tree);
132 static void maybe_warn_about_overly_private_class (tree);
133 static int method_name_cmp (const void *, const void *);
134 static int resort_method_name_cmp (const void *, const void *);
135 static void add_implicitly_declared_members (tree, int, int);
136 static tree fixed_type_or_null (tree, int *, int *);
137 static tree build_simple_base_path (tree expr, tree binfo);
138 static tree build_vtbl_ref_1 (tree, tree);
139 static tree build_vtbl_initializer (tree, tree, tree, tree, int *);
140 static int count_fields (tree);
141 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
142 static bool check_bitfield_decl (tree);
143 static void check_field_decl (tree, tree, int *, int *, int *);
144 static void check_field_decls (tree, tree *, int *, int *);
145 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
146 static void build_base_fields (record_layout_info, splay_tree, tree *);
147 static void check_methods (tree);
148 static void remove_zero_width_bit_fields (tree);
149 static void check_bases (tree, int *, int *);
150 static void check_bases_and_members (tree);
151 static tree create_vtable_ptr (tree, tree *);
152 static void include_empty_classes (record_layout_info);
153 static void layout_class_type (tree, tree *);
154 static void fixup_pending_inline (tree);
155 static void fixup_inline_methods (tree);
156 static void propagate_binfo_offsets (tree, tree);
157 static void layout_virtual_bases (record_layout_info, splay_tree);
158 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
159 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
160 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
161 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
162 static void add_vcall_offset (tree, tree, vtbl_init_data *);
163 static void layout_vtable_decl (tree, int);
164 static tree dfs_find_final_overrider_pre (tree, void *);
165 static tree dfs_find_final_overrider_post (tree, void *);
166 static tree find_final_overrider (tree, tree, tree);
167 static int make_new_vtable (tree, tree);
168 static tree get_primary_binfo (tree);
169 static int maybe_indent_hierarchy (FILE *, int, int);
170 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
171 static void dump_class_hierarchy (tree);
172 static void dump_class_hierarchy_1 (FILE *, int, tree);
173 static void dump_array (FILE *, tree);
174 static void dump_vtable (tree, tree, tree);
175 static void dump_vtt (tree, tree);
176 static void dump_thunk (FILE *, int, tree);
177 static tree build_vtable (tree, tree, tree);
178 static void initialize_vtable (tree, tree);
179 static void layout_nonempty_base_or_field (record_layout_info,
180 tree, tree, splay_tree);
181 static tree end_of_class (tree, int);
182 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
183 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree);
184 static tree dfs_accumulate_vtbl_inits (tree, tree, tree, tree,
186 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
187 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
188 static void clone_constructors_and_destructors (tree);
189 static tree build_clone (tree, tree);
190 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
191 static void build_ctor_vtbl_group (tree, tree);
192 static void build_vtt (tree);
193 static tree binfo_ctor_vtable (tree);
194 static tree *build_vtt_inits (tree, tree, tree *, tree *);
195 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
196 static tree dfs_fixup_binfo_vtbls (tree, void *);
197 static int record_subobject_offset (tree, tree, splay_tree);
198 static int check_subobject_offset (tree, tree, splay_tree);
199 static int walk_subobject_offsets (tree, subobject_offset_fn,
200 tree, splay_tree, tree, int);
201 static void record_subobject_offsets (tree, tree, splay_tree, bool);
202 static int layout_conflict_p (tree, tree, splay_tree, int);
203 static int splay_tree_compare_integer_csts (splay_tree_key k1,
205 static void warn_about_ambiguous_bases (tree);
206 static bool type_requires_array_cookie (tree);
207 static bool contains_empty_class_p (tree);
208 static bool base_derived_from (tree, tree);
209 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
210 static tree end_of_base (tree);
211 static tree get_vcall_index (tree, tree);
213 /* Variables shared between class.c and call.c. */
215 #ifdef GATHER_STATISTICS
217 int n_vtable_entries = 0;
218 int n_vtable_searches = 0;
219 int n_vtable_elems = 0;
220 int n_convert_harshness = 0;
221 int n_compute_conversion_costs = 0;
222 int n_inner_fields_searched = 0;
225 /* Convert to or from a base subobject. EXPR is an expression of type
226 `A' or `A*', an expression of type `B' or `B*' is returned. To
227 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
228 the B base instance within A. To convert base A to derived B, CODE
229 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
230 In this latter case, A must not be a morally virtual base of B.
231 NONNULL is true if EXPR is known to be non-NULL (this is only
232 needed when EXPR is of pointer type). CV qualifiers are preserved
236 build_base_path (enum tree_code code,
241 tree v_binfo = NULL_TREE;
242 tree d_binfo = NULL_TREE;
246 tree null_test = NULL;
247 tree ptr_target_type;
249 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
250 bool has_empty = false;
253 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
254 return error_mark_node;
256 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
259 if (is_empty_class (BINFO_TYPE (probe)))
261 if (!v_binfo && BINFO_VIRTUAL_P (probe))
265 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
267 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
269 gcc_assert ((code == MINUS_EXPR
270 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
271 || (code == PLUS_EXPR
272 && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
274 if (binfo == d_binfo)
278 if (code == MINUS_EXPR && v_binfo)
280 error ("cannot convert from base %qT to derived type %qT via virtual base %qT",
281 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
282 return error_mark_node;
286 /* This must happen before the call to save_expr. */
287 expr = build_unary_op (ADDR_EXPR, expr, 0);
289 offset = BINFO_OFFSET (binfo);
290 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
291 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
293 /* Do we need to look in the vtable for the real offset? */
294 /* Don't bother inside sizeof; the source type might not be complete. */
295 virtual_access = (v_binfo && fixed_type_p <= 0) && !skip_evaluation;
297 /* Do we need to check for a null pointer? */
298 if (want_pointer && !nonnull)
300 /* If we know the conversion will not actually change the value
301 of EXPR, then we can avoid testing the expression for NULL.
302 We have to avoid generating a COMPONENT_REF for a base class
303 field, because other parts of the compiler know that such
304 expressions are always non-NULL. */
305 if (!virtual_access && integer_zerop (offset))
308 /* TARGET_TYPE has been extracted from BINFO, and, is
309 therefore always cv-unqualified. Extract the
310 cv-qualifiers from EXPR so that the expression returned
311 matches the input. */
312 class_type = TREE_TYPE (TREE_TYPE (expr));
314 = cp_build_qualified_type (target_type,
315 cp_type_quals (class_type));
316 return build_nop (build_pointer_type (target_type), expr);
318 null_test = error_mark_node;
321 /* Protect against multiple evaluation if necessary. */
322 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
323 expr = save_expr (expr);
325 /* Now that we've saved expr, build the real null test. */
328 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
329 null_test = fold_build2 (NE_EXPR, boolean_type_node,
333 /* If this is a simple base reference, express it as a COMPONENT_REF. */
334 if (code == PLUS_EXPR && !virtual_access
335 /* We don't build base fields for empty bases, and they aren't very
336 interesting to the optimizers anyway. */
339 expr = build_indirect_ref (expr, NULL);
340 expr = build_simple_base_path (expr, binfo);
342 expr = build_address (expr);
343 target_type = TREE_TYPE (expr);
349 /* Going via virtual base V_BINFO. We need the static offset
350 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
351 V_BINFO. That offset is an entry in D_BINFO's vtable. */
354 if (fixed_type_p < 0 && in_base_initializer)
356 /* In a base member initializer, we cannot rely on the
357 vtable being set up. We have to indirect via the
361 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
362 t = build_pointer_type (t);
363 v_offset = convert (t, current_vtt_parm);
364 v_offset = build_indirect_ref (v_offset, NULL);
367 v_offset = build_vfield_ref (build_indirect_ref (expr, NULL),
368 TREE_TYPE (TREE_TYPE (expr)));
370 v_offset = build2 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
371 v_offset, fold_convert (sizetype, BINFO_VPTR_FIELD (v_binfo)));
372 v_offset = build1 (NOP_EXPR,
373 build_pointer_type (ptrdiff_type_node),
375 v_offset = build_indirect_ref (v_offset, NULL);
376 TREE_CONSTANT (v_offset) = 1;
377 TREE_INVARIANT (v_offset) = 1;
379 offset = convert_to_integer (ptrdiff_type_node,
381 BINFO_OFFSET (v_binfo)));
383 if (!integer_zerop (offset))
384 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
386 if (fixed_type_p < 0)
387 /* Negative fixed_type_p means this is a constructor or destructor;
388 virtual base layout is fixed in in-charge [cd]tors, but not in
390 offset = build3 (COND_EXPR, ptrdiff_type_node,
391 build2 (EQ_EXPR, boolean_type_node,
392 current_in_charge_parm, integer_zero_node),
394 convert_to_integer (ptrdiff_type_node,
395 BINFO_OFFSET (binfo)));
400 target_type = cp_build_qualified_type
401 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
402 ptr_target_type = build_pointer_type (target_type);
404 target_type = ptr_target_type;
406 expr = build1 (NOP_EXPR, ptr_target_type, expr);
408 if (!integer_zerop (offset))
410 offset = fold_convert (sizetype, offset);
411 if (code == MINUS_EXPR)
412 offset = fold_build1 (NEGATE_EXPR, sizetype, offset);
413 expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
419 expr = build_indirect_ref (expr, NULL);
423 expr = fold_build3 (COND_EXPR, target_type, null_test, expr,
424 fold_build1 (NOP_EXPR, target_type,
430 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
431 Perform a derived-to-base conversion by recursively building up a
432 sequence of COMPONENT_REFs to the appropriate base fields. */
435 build_simple_base_path (tree expr, tree binfo)
437 tree type = BINFO_TYPE (binfo);
438 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
441 if (d_binfo == NULL_TREE)
445 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
447 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
448 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
449 an lvalue in the front end; only _DECLs and _REFs are lvalues
451 temp = unary_complex_lvalue (ADDR_EXPR, expr);
453 expr = build_indirect_ref (temp, NULL);
459 expr = build_simple_base_path (expr, d_binfo);
461 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
462 field; field = TREE_CHAIN (field))
463 /* Is this the base field created by build_base_field? */
464 if (TREE_CODE (field) == FIELD_DECL
465 && DECL_FIELD_IS_BASE (field)
466 && TREE_TYPE (field) == type)
468 /* We don't use build_class_member_access_expr here, as that
469 has unnecessary checks, and more importantly results in
470 recursive calls to dfs_walk_once. */
471 int type_quals = cp_type_quals (TREE_TYPE (expr));
473 expr = build3 (COMPONENT_REF,
474 cp_build_qualified_type (type, type_quals),
475 expr, field, NULL_TREE);
476 expr = fold_if_not_in_template (expr);
478 /* Mark the expression const or volatile, as appropriate.
479 Even though we've dealt with the type above, we still have
480 to mark the expression itself. */
481 if (type_quals & TYPE_QUAL_CONST)
482 TREE_READONLY (expr) = 1;
483 if (type_quals & TYPE_QUAL_VOLATILE)
484 TREE_THIS_VOLATILE (expr) = 1;
489 /* Didn't find the base field?!? */
493 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
494 type is a class type or a pointer to a class type. In the former
495 case, TYPE is also a class type; in the latter it is another
496 pointer type. If CHECK_ACCESS is true, an error message is emitted
497 if TYPE is inaccessible. If OBJECT has pointer type, the value is
498 assumed to be non-NULL. */
501 convert_to_base (tree object, tree type, bool check_access, bool nonnull)
506 if (TYPE_PTR_P (TREE_TYPE (object)))
508 object_type = TREE_TYPE (TREE_TYPE (object));
509 type = TREE_TYPE (type);
512 object_type = TREE_TYPE (object);
514 binfo = lookup_base (object_type, type,
515 check_access ? ba_check : ba_unique,
517 if (!binfo || binfo == error_mark_node)
518 return error_mark_node;
520 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
523 /* EXPR is an expression with unqualified class type. BASE is a base
524 binfo of that class type. Returns EXPR, converted to the BASE
525 type. This function assumes that EXPR is the most derived class;
526 therefore virtual bases can be found at their static offsets. */
529 convert_to_base_statically (tree expr, tree base)
533 expr_type = TREE_TYPE (expr);
534 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
538 pointer_type = build_pointer_type (expr_type);
540 /* We use fold_build2 and fold_convert below to simplify the trees
541 provided to the optimizers. It is not safe to call these functions
542 when processing a template because they do not handle C++-specific
544 gcc_assert (!processing_template_decl);
545 expr = build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1);
546 if (!integer_zerop (BINFO_OFFSET (base)))
547 expr = fold_build2 (POINTER_PLUS_EXPR, pointer_type, expr,
548 fold_convert (sizetype, BINFO_OFFSET (base)));
549 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
550 expr = build_fold_indirect_ref (expr);
558 build_vfield_ref (tree datum, tree type)
560 tree vfield, vcontext;
562 if (datum == error_mark_node)
563 return error_mark_node;
565 /* First, convert to the requested type. */
566 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
567 datum = convert_to_base (datum, type, /*check_access=*/false,
570 /* Second, the requested type may not be the owner of its own vptr.
571 If not, convert to the base class that owns it. We cannot use
572 convert_to_base here, because VCONTEXT may appear more than once
573 in the inheritance hierarchy of TYPE, and thus direct conversion
574 between the types may be ambiguous. Following the path back up
575 one step at a time via primary bases avoids the problem. */
576 vfield = TYPE_VFIELD (type);
577 vcontext = DECL_CONTEXT (vfield);
578 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
580 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
581 type = TREE_TYPE (datum);
584 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
587 /* Given an object INSTANCE, return an expression which yields the
588 vtable element corresponding to INDEX. There are many special
589 cases for INSTANCE which we take care of here, mainly to avoid
590 creating extra tree nodes when we don't have to. */
593 build_vtbl_ref_1 (tree instance, tree idx)
596 tree vtbl = NULL_TREE;
598 /* Try to figure out what a reference refers to, and
599 access its virtual function table directly. */
602 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
604 tree basetype = non_reference (TREE_TYPE (instance));
606 if (fixed_type && !cdtorp)
608 tree binfo = lookup_base (fixed_type, basetype,
609 ba_unique | ba_quiet, NULL);
611 vtbl = unshare_expr (BINFO_VTABLE (binfo));
615 vtbl = build_vfield_ref (instance, basetype);
617 assemble_external (vtbl);
619 aref = build_array_ref (vtbl, idx);
620 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
621 TREE_INVARIANT (aref) = TREE_CONSTANT (aref);
627 build_vtbl_ref (tree instance, tree idx)
629 tree aref = build_vtbl_ref_1 (instance, idx);
634 /* Given a stable object pointer INSTANCE_PTR, return an expression which
635 yields a function pointer corresponding to vtable element INDEX. */
638 build_vfn_ref (tree instance_ptr, tree idx)
642 aref = build_vtbl_ref_1 (build_indirect_ref (instance_ptr, 0), idx);
644 /* When using function descriptors, the address of the
645 vtable entry is treated as a function pointer. */
646 if (TARGET_VTABLE_USES_DESCRIPTORS)
647 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
648 build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1));
650 /* Remember this as a method reference, for later devirtualization. */
651 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
656 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
657 for the given TYPE. */
660 get_vtable_name (tree type)
662 return mangle_vtbl_for_type (type);
665 /* DECL is an entity associated with TYPE, like a virtual table or an
666 implicitly generated constructor. Determine whether or not DECL
667 should have external or internal linkage at the object file
668 level. This routine does not deal with COMDAT linkage and other
669 similar complexities; it simply sets TREE_PUBLIC if it possible for
670 entities in other translation units to contain copies of DECL, in
674 set_linkage_according_to_type (tree type, tree decl)
676 /* If TYPE involves a local class in a function with internal
677 linkage, then DECL should have internal linkage too. Other local
678 classes have no linkage -- but if their containing functions
679 have external linkage, it makes sense for DECL to have external
680 linkage too. That will allow template definitions to be merged,
682 if (no_linkage_check (type, /*relaxed_p=*/true))
684 TREE_PUBLIC (decl) = 0;
685 DECL_INTERFACE_KNOWN (decl) = 1;
688 TREE_PUBLIC (decl) = 1;
691 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
692 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
693 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
696 build_vtable (tree class_type, tree name, tree vtable_type)
700 decl = build_lang_decl (VAR_DECL, name, vtable_type);
701 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
702 now to avoid confusion in mangle_decl. */
703 SET_DECL_ASSEMBLER_NAME (decl, name);
704 DECL_CONTEXT (decl) = class_type;
705 DECL_ARTIFICIAL (decl) = 1;
706 TREE_STATIC (decl) = 1;
707 TREE_READONLY (decl) = 1;
708 DECL_VIRTUAL_P (decl) = 1;
709 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
710 DECL_VTABLE_OR_VTT_P (decl) = 1;
711 /* At one time the vtable info was grabbed 2 words at a time. This
712 fails on sparc unless you have 8-byte alignment. (tiemann) */
713 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
715 set_linkage_according_to_type (class_type, decl);
716 /* The vtable has not been defined -- yet. */
717 DECL_EXTERNAL (decl) = 1;
718 DECL_NOT_REALLY_EXTERN (decl) = 1;
720 /* Mark the VAR_DECL node representing the vtable itself as a
721 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
722 is rather important that such things be ignored because any
723 effort to actually generate DWARF for them will run into
724 trouble when/if we encounter code like:
727 struct S { virtual void member (); };
729 because the artificial declaration of the vtable itself (as
730 manufactured by the g++ front end) will say that the vtable is
731 a static member of `S' but only *after* the debug output for
732 the definition of `S' has already been output. This causes
733 grief because the DWARF entry for the definition of the vtable
734 will try to refer back to an earlier *declaration* of the
735 vtable as a static member of `S' and there won't be one. We
736 might be able to arrange to have the "vtable static member"
737 attached to the member list for `S' before the debug info for
738 `S' get written (which would solve the problem) but that would
739 require more intrusive changes to the g++ front end. */
740 DECL_IGNORED_P (decl) = 1;
745 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
746 or even complete. If this does not exist, create it. If COMPLETE is
747 nonzero, then complete the definition of it -- that will render it
748 impossible to actually build the vtable, but is useful to get at those
749 which are known to exist in the runtime. */
752 get_vtable_decl (tree type, int complete)
756 if (CLASSTYPE_VTABLES (type))
757 return CLASSTYPE_VTABLES (type);
759 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
760 CLASSTYPE_VTABLES (type) = decl;
764 DECL_EXTERNAL (decl) = 1;
765 finish_decl (decl, NULL_TREE, NULL_TREE);
771 /* Build the primary virtual function table for TYPE. If BINFO is
772 non-NULL, build the vtable starting with the initial approximation
773 that it is the same as the one which is the head of the association
774 list. Returns a nonzero value if a new vtable is actually
778 build_primary_vtable (tree binfo, tree type)
783 decl = get_vtable_decl (type, /*complete=*/0);
787 if (BINFO_NEW_VTABLE_MARKED (binfo))
788 /* We have already created a vtable for this base, so there's
789 no need to do it again. */
792 virtuals = copy_list (BINFO_VIRTUALS (binfo));
793 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
794 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
795 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
799 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
800 virtuals = NULL_TREE;
803 #ifdef GATHER_STATISTICS
805 n_vtable_elems += list_length (virtuals);
808 /* Initialize the association list for this type, based
809 on our first approximation. */
810 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
811 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
812 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
816 /* Give BINFO a new virtual function table which is initialized
817 with a skeleton-copy of its original initialization. The only
818 entry that changes is the `delta' entry, so we can really
819 share a lot of structure.
821 FOR_TYPE is the most derived type which caused this table to
824 Returns nonzero if we haven't met BINFO before.
826 The order in which vtables are built (by calling this function) for
827 an object must remain the same, otherwise a binary incompatibility
831 build_secondary_vtable (tree binfo)
833 if (BINFO_NEW_VTABLE_MARKED (binfo))
834 /* We already created a vtable for this base. There's no need to
838 /* Remember that we've created a vtable for this BINFO, so that we
839 don't try to do so again. */
840 SET_BINFO_NEW_VTABLE_MARKED (binfo);
842 /* Make fresh virtual list, so we can smash it later. */
843 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
845 /* Secondary vtables are laid out as part of the same structure as
846 the primary vtable. */
847 BINFO_VTABLE (binfo) = NULL_TREE;
851 /* Create a new vtable for BINFO which is the hierarchy dominated by
852 T. Return nonzero if we actually created a new vtable. */
855 make_new_vtable (tree t, tree binfo)
857 if (binfo == TYPE_BINFO (t))
858 /* In this case, it is *type*'s vtable we are modifying. We start
859 with the approximation that its vtable is that of the
860 immediate base class. */
861 return build_primary_vtable (binfo, t);
863 /* This is our very own copy of `basetype' to play with. Later,
864 we will fill in all the virtual functions that override the
865 virtual functions in these base classes which are not defined
866 by the current type. */
867 return build_secondary_vtable (binfo);
870 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
871 (which is in the hierarchy dominated by T) list FNDECL as its
872 BV_FN. DELTA is the required constant adjustment from the `this'
873 pointer where the vtable entry appears to the `this' required when
874 the function is actually called. */
877 modify_vtable_entry (tree t,
887 if (fndecl != BV_FN (v)
888 || !tree_int_cst_equal (delta, BV_DELTA (v)))
890 /* We need a new vtable for BINFO. */
891 if (make_new_vtable (t, binfo))
893 /* If we really did make a new vtable, we also made a copy
894 of the BINFO_VIRTUALS list. Now, we have to find the
895 corresponding entry in that list. */
896 *virtuals = BINFO_VIRTUALS (binfo);
897 while (BV_FN (*virtuals) != BV_FN (v))
898 *virtuals = TREE_CHAIN (*virtuals);
902 BV_DELTA (v) = delta;
903 BV_VCALL_INDEX (v) = NULL_TREE;
909 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
910 the USING_DECL naming METHOD. Returns true if the method could be
911 added to the method vec. */
914 add_method (tree type, tree method, tree using_decl)
918 bool template_conv_p = false;
920 VEC(tree,gc) *method_vec;
922 bool insert_p = false;
926 if (method == error_mark_node)
929 complete_p = COMPLETE_TYPE_P (type);
930 conv_p = DECL_CONV_FN_P (method);
932 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
933 && DECL_TEMPLATE_CONV_FN_P (method));
935 method_vec = CLASSTYPE_METHOD_VEC (type);
938 /* Make a new method vector. We start with 8 entries. We must
939 allocate at least two (for constructors and destructors), and
940 we're going to end up with an assignment operator at some
942 method_vec = VEC_alloc (tree, gc, 8);
943 /* Create slots for constructors and destructors. */
944 VEC_quick_push (tree, method_vec, NULL_TREE);
945 VEC_quick_push (tree, method_vec, NULL_TREE);
946 CLASSTYPE_METHOD_VEC (type) = method_vec;
949 /* Maintain TYPE_HAS_CONSTRUCTOR, etc. */
950 grok_special_member_properties (method);
952 /* Constructors and destructors go in special slots. */
953 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
954 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
955 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
957 slot = CLASSTYPE_DESTRUCTOR_SLOT;
959 if (TYPE_FOR_JAVA (type))
961 if (!DECL_ARTIFICIAL (method))
962 error ("Java class %qT cannot have a destructor", type);
963 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
964 error ("Java class %qT cannot have an implicit non-trivial "
974 /* See if we already have an entry with this name. */
975 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
976 VEC_iterate (tree, method_vec, slot, m);
982 if (TREE_CODE (m) == TEMPLATE_DECL
983 && DECL_TEMPLATE_CONV_FN_P (m))
987 if (conv_p && !DECL_CONV_FN_P (m))
989 if (DECL_NAME (m) == DECL_NAME (method))
995 && !DECL_CONV_FN_P (m)
996 && DECL_NAME (m) > DECL_NAME (method))
1000 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1002 /* Check to see if we've already got this method. */
1003 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1005 tree fn = OVL_CURRENT (fns);
1011 if (TREE_CODE (fn) != TREE_CODE (method))
1014 /* [over.load] Member function declarations with the
1015 same name and the same parameter types cannot be
1016 overloaded if any of them is a static member
1017 function declaration.
1019 [namespace.udecl] When a using-declaration brings names
1020 from a base class into a derived class scope, member
1021 functions in the derived class override and/or hide member
1022 functions with the same name and parameter types in a base
1023 class (rather than conflicting). */
1024 fn_type = TREE_TYPE (fn);
1025 method_type = TREE_TYPE (method);
1026 parms1 = TYPE_ARG_TYPES (fn_type);
1027 parms2 = TYPE_ARG_TYPES (method_type);
1029 /* Compare the quals on the 'this' parm. Don't compare
1030 the whole types, as used functions are treated as
1031 coming from the using class in overload resolution. */
1032 if (! DECL_STATIC_FUNCTION_P (fn)
1033 && ! DECL_STATIC_FUNCTION_P (method)
1034 && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
1035 != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
1038 /* For templates, the return type and template parameters
1039 must be identical. */
1040 if (TREE_CODE (fn) == TEMPLATE_DECL
1041 && (!same_type_p (TREE_TYPE (fn_type),
1042 TREE_TYPE (method_type))
1043 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1044 DECL_TEMPLATE_PARMS (method))))
1047 if (! DECL_STATIC_FUNCTION_P (fn))
1048 parms1 = TREE_CHAIN (parms1);
1049 if (! DECL_STATIC_FUNCTION_P (method))
1050 parms2 = TREE_CHAIN (parms2);
1052 if (compparms (parms1, parms2)
1053 && (!DECL_CONV_FN_P (fn)
1054 || same_type_p (TREE_TYPE (fn_type),
1055 TREE_TYPE (method_type))))
1059 if (DECL_CONTEXT (fn) == type)
1060 /* Defer to the local function. */
1062 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1063 error ("repeated using declaration %q+D", using_decl);
1065 error ("using declaration %q+D conflicts with a previous using declaration",
1070 error ("%q+#D cannot be overloaded", method);
1071 error ("with %q+#D", fn);
1074 /* We don't call duplicate_decls here to merge the
1075 declarations because that will confuse things if the
1076 methods have inline definitions. In particular, we
1077 will crash while processing the definitions. */
1082 /* A class should never have more than one destructor. */
1083 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1086 /* Add the new binding. */
1087 overload = build_overload (method, current_fns);
1090 TYPE_HAS_CONVERSION (type) = 1;
1091 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1092 push_class_level_binding (DECL_NAME (method), overload);
1098 /* We only expect to add few methods in the COMPLETE_P case, so
1099 just make room for one more method in that case. */
1101 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1103 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1105 CLASSTYPE_METHOD_VEC (type) = method_vec;
1106 if (slot == VEC_length (tree, method_vec))
1107 VEC_quick_push (tree, method_vec, overload);
1109 VEC_quick_insert (tree, method_vec, slot, overload);
1112 /* Replace the current slot. */
1113 VEC_replace (tree, method_vec, slot, overload);
1117 /* Subroutines of finish_struct. */
1119 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1120 legit, otherwise return 0. */
1123 alter_access (tree t, tree fdecl, tree access)
1127 if (!DECL_LANG_SPECIFIC (fdecl))
1128 retrofit_lang_decl (fdecl);
1130 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1132 elem = purpose_member (t, DECL_ACCESS (fdecl));
1135 if (TREE_VALUE (elem) != access)
1137 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1138 error ("conflicting access specifications for method"
1139 " %q+D, ignored", TREE_TYPE (fdecl));
1141 error ("conflicting access specifications for field %qE, ignored",
1146 /* They're changing the access to the same thing they changed
1147 it to before. That's OK. */
1153 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1154 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1160 /* Process the USING_DECL, which is a member of T. */
1163 handle_using_decl (tree using_decl, tree t)
1165 tree decl = USING_DECL_DECLS (using_decl);
1166 tree name = DECL_NAME (using_decl);
1168 = TREE_PRIVATE (using_decl) ? access_private_node
1169 : TREE_PROTECTED (using_decl) ? access_protected_node
1170 : access_public_node;
1171 tree flist = NULL_TREE;
1174 gcc_assert (!processing_template_decl && decl);
1176 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1179 if (is_overloaded_fn (old_value))
1180 old_value = OVL_CURRENT (old_value);
1182 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1185 old_value = NULL_TREE;
1188 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1190 if (is_overloaded_fn (decl))
1195 else if (is_overloaded_fn (old_value))
1198 /* It's OK to use functions from a base when there are functions with
1199 the same name already present in the current class. */;
1202 error ("%q+D invalid in %q#T", using_decl, t);
1203 error (" because of local method %q+#D with same name",
1204 OVL_CURRENT (old_value));
1208 else if (!DECL_ARTIFICIAL (old_value))
1210 error ("%q+D invalid in %q#T", using_decl, t);
1211 error (" because of local member %q+#D with same name", old_value);
1215 /* Make type T see field decl FDECL with access ACCESS. */
1217 for (; flist; flist = OVL_NEXT (flist))
1219 add_method (t, OVL_CURRENT (flist), using_decl);
1220 alter_access (t, OVL_CURRENT (flist), access);
1223 alter_access (t, decl, access);
1226 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1227 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1228 properties of the bases. */
1231 check_bases (tree t,
1232 int* cant_have_const_ctor_p,
1233 int* no_const_asn_ref_p)
1236 int seen_non_virtual_nearly_empty_base_p;
1240 seen_non_virtual_nearly_empty_base_p = 0;
1242 for (binfo = TYPE_BINFO (t), i = 0;
1243 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1245 tree basetype = TREE_TYPE (base_binfo);
1247 gcc_assert (COMPLETE_TYPE_P (basetype));
1249 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1250 here because the case of virtual functions but non-virtual
1251 dtor is handled in finish_struct_1. */
1252 if (!TYPE_POLYMORPHIC_P (basetype))
1253 warning (OPT_Weffc__,
1254 "base class %q#T has a non-virtual destructor", basetype);
1256 /* If the base class doesn't have copy constructors or
1257 assignment operators that take const references, then the
1258 derived class cannot have such a member automatically
1260 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1261 *cant_have_const_ctor_p = 1;
1262 if (TYPE_HAS_ASSIGN_REF (basetype)
1263 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1264 *no_const_asn_ref_p = 1;
1266 if (BINFO_VIRTUAL_P (base_binfo))
1267 /* A virtual base does not effect nearly emptiness. */
1269 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1271 if (seen_non_virtual_nearly_empty_base_p)
1272 /* And if there is more than one nearly empty base, then the
1273 derived class is not nearly empty either. */
1274 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1276 /* Remember we've seen one. */
1277 seen_non_virtual_nearly_empty_base_p = 1;
1279 else if (!is_empty_class (basetype))
1280 /* If the base class is not empty or nearly empty, then this
1281 class cannot be nearly empty. */
1282 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1284 /* A lot of properties from the bases also apply to the derived
1286 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1287 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1288 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1289 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1290 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1291 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1292 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1293 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1294 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1295 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (basetype);
1299 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1300 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1301 that have had a nearly-empty virtual primary base stolen by some
1302 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1306 determine_primary_bases (tree t)
1309 tree primary = NULL_TREE;
1310 tree type_binfo = TYPE_BINFO (t);
1313 /* Determine the primary bases of our bases. */
1314 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1315 base_binfo = TREE_CHAIN (base_binfo))
1317 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1319 /* See if we're the non-virtual primary of our inheritance
1321 if (!BINFO_VIRTUAL_P (base_binfo))
1323 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1324 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1327 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1328 BINFO_TYPE (parent_primary)))
1329 /* We are the primary binfo. */
1330 BINFO_PRIMARY_P (base_binfo) = 1;
1332 /* Determine if we have a virtual primary base, and mark it so.
1334 if (primary && BINFO_VIRTUAL_P (primary))
1336 tree this_primary = copied_binfo (primary, base_binfo);
1338 if (BINFO_PRIMARY_P (this_primary))
1339 /* Someone already claimed this base. */
1340 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1345 BINFO_PRIMARY_P (this_primary) = 1;
1346 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1348 /* A virtual binfo might have been copied from within
1349 another hierarchy. As we're about to use it as a
1350 primary base, make sure the offsets match. */
1351 delta = size_diffop (convert (ssizetype,
1352 BINFO_OFFSET (base_binfo)),
1354 BINFO_OFFSET (this_primary)));
1356 propagate_binfo_offsets (this_primary, delta);
1361 /* First look for a dynamic direct non-virtual base. */
1362 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1364 tree basetype = BINFO_TYPE (base_binfo);
1366 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1368 primary = base_binfo;
1373 /* A "nearly-empty" virtual base class can be the primary base
1374 class, if no non-virtual polymorphic base can be found. Look for
1375 a nearly-empty virtual dynamic base that is not already a primary
1376 base of something in the hierarchy. If there is no such base,
1377 just pick the first nearly-empty virtual base. */
1379 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1380 base_binfo = TREE_CHAIN (base_binfo))
1381 if (BINFO_VIRTUAL_P (base_binfo)
1382 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1384 if (!BINFO_PRIMARY_P (base_binfo))
1386 /* Found one that is not primary. */
1387 primary = base_binfo;
1391 /* Remember the first candidate. */
1392 primary = base_binfo;
1396 /* If we've got a primary base, use it. */
1399 tree basetype = BINFO_TYPE (primary);
1401 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1402 if (BINFO_PRIMARY_P (primary))
1403 /* We are stealing a primary base. */
1404 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1405 BINFO_PRIMARY_P (primary) = 1;
1406 if (BINFO_VIRTUAL_P (primary))
1410 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1411 /* A virtual binfo might have been copied from within
1412 another hierarchy. As we're about to use it as a primary
1413 base, make sure the offsets match. */
1414 delta = size_diffop (ssize_int (0),
1415 convert (ssizetype, BINFO_OFFSET (primary)));
1417 propagate_binfo_offsets (primary, delta);
1420 primary = TYPE_BINFO (basetype);
1422 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1423 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1424 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1428 /* Set memoizing fields and bits of T (and its variants) for later
1432 finish_struct_bits (tree t)
1436 /* Fix up variants (if any). */
1437 for (variants = TYPE_NEXT_VARIANT (t);
1439 variants = TYPE_NEXT_VARIANT (variants))
1441 /* These fields are in the _TYPE part of the node, not in
1442 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1443 TYPE_HAS_CONSTRUCTOR (variants) = TYPE_HAS_CONSTRUCTOR (t);
1444 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1445 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1446 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1448 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1450 TYPE_BINFO (variants) = TYPE_BINFO (t);
1452 /* Copy whatever these are holding today. */
1453 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1454 TYPE_METHODS (variants) = TYPE_METHODS (t);
1455 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1457 /* All variants of a class have the same attributes. */
1458 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1461 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1462 /* For a class w/o baseclasses, 'finish_struct' has set
1463 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1464 Similarly for a class whose base classes do not have vtables.
1465 When neither of these is true, we might have removed abstract
1466 virtuals (by providing a definition), added some (by declaring
1467 new ones), or redeclared ones from a base class. We need to
1468 recalculate what's really an abstract virtual at this point (by
1469 looking in the vtables). */
1470 get_pure_virtuals (t);
1472 /* If this type has a copy constructor or a destructor, force its
1473 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1474 nonzero. This will cause it to be passed by invisible reference
1475 and prevent it from being returned in a register. */
1476 if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1479 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1480 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1482 TYPE_MODE (variants) = BLKmode;
1483 TREE_ADDRESSABLE (variants) = 1;
1488 /* Issue warnings about T having private constructors, but no friends,
1491 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1492 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1493 non-private static member functions. */
1496 maybe_warn_about_overly_private_class (tree t)
1498 int has_member_fn = 0;
1499 int has_nonprivate_method = 0;
1502 if (!warn_ctor_dtor_privacy
1503 /* If the class has friends, those entities might create and
1504 access instances, so we should not warn. */
1505 || (CLASSTYPE_FRIEND_CLASSES (t)
1506 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1507 /* We will have warned when the template was declared; there's
1508 no need to warn on every instantiation. */
1509 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1510 /* There's no reason to even consider warning about this
1514 /* We only issue one warning, if more than one applies, because
1515 otherwise, on code like:
1518 // Oops - forgot `public:'
1524 we warn several times about essentially the same problem. */
1526 /* Check to see if all (non-constructor, non-destructor) member
1527 functions are private. (Since there are no friends or
1528 non-private statics, we can't ever call any of the private member
1530 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1531 /* We're not interested in compiler-generated methods; they don't
1532 provide any way to call private members. */
1533 if (!DECL_ARTIFICIAL (fn))
1535 if (!TREE_PRIVATE (fn))
1537 if (DECL_STATIC_FUNCTION_P (fn))
1538 /* A non-private static member function is just like a
1539 friend; it can create and invoke private member
1540 functions, and be accessed without a class
1544 has_nonprivate_method = 1;
1545 /* Keep searching for a static member function. */
1547 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1551 if (!has_nonprivate_method && has_member_fn)
1553 /* There are no non-private methods, and there's at least one
1554 private member function that isn't a constructor or
1555 destructor. (If all the private members are
1556 constructors/destructors we want to use the code below that
1557 issues error messages specifically referring to
1558 constructors/destructors.) */
1560 tree binfo = TYPE_BINFO (t);
1562 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1563 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1565 has_nonprivate_method = 1;
1568 if (!has_nonprivate_method)
1570 warning (OPT_Wctor_dtor_privacy,
1571 "all member functions in class %qT are private", t);
1576 /* Even if some of the member functions are non-private, the class
1577 won't be useful for much if all the constructors or destructors
1578 are private: such an object can never be created or destroyed. */
1579 fn = CLASSTYPE_DESTRUCTORS (t);
1580 if (fn && TREE_PRIVATE (fn))
1582 warning (OPT_Wctor_dtor_privacy,
1583 "%q#T only defines a private destructor and has no friends",
1588 if (TYPE_HAS_CONSTRUCTOR (t)
1589 /* Implicitly generated constructors are always public. */
1590 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1591 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1593 int nonprivate_ctor = 0;
1595 /* If a non-template class does not define a copy
1596 constructor, one is defined for it, enabling it to avoid
1597 this warning. For a template class, this does not
1598 happen, and so we would normally get a warning on:
1600 template <class T> class C { private: C(); };
1602 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1603 complete non-template or fully instantiated classes have this
1605 if (!TYPE_HAS_INIT_REF (t))
1606 nonprivate_ctor = 1;
1608 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1610 tree ctor = OVL_CURRENT (fn);
1611 /* Ideally, we wouldn't count copy constructors (or, in
1612 fact, any constructor that takes an argument of the
1613 class type as a parameter) because such things cannot
1614 be used to construct an instance of the class unless
1615 you already have one. But, for now at least, we're
1617 if (! TREE_PRIVATE (ctor))
1619 nonprivate_ctor = 1;
1624 if (nonprivate_ctor == 0)
1626 warning (OPT_Wctor_dtor_privacy,
1627 "%q#T only defines private constructors and has no friends",
1635 gt_pointer_operator new_value;
1639 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1642 method_name_cmp (const void* m1_p, const void* m2_p)
1644 const tree *const m1 = (const tree *) m1_p;
1645 const tree *const m2 = (const tree *) m2_p;
1647 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1649 if (*m1 == NULL_TREE)
1651 if (*m2 == NULL_TREE)
1653 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1658 /* This routine compares two fields like method_name_cmp but using the
1659 pointer operator in resort_field_decl_data. */
1662 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1664 const tree *const m1 = (const tree *) m1_p;
1665 const tree *const m2 = (const tree *) m2_p;
1666 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1668 if (*m1 == NULL_TREE)
1670 if (*m2 == NULL_TREE)
1673 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1674 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1675 resort_data.new_value (&d1, resort_data.cookie);
1676 resort_data.new_value (&d2, resort_data.cookie);
1683 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1686 resort_type_method_vec (void* obj,
1687 void* orig_obj ATTRIBUTE_UNUSED ,
1688 gt_pointer_operator new_value,
1691 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1692 int len = VEC_length (tree, method_vec);
1696 /* The type conversion ops have to live at the front of the vec, so we
1698 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1699 VEC_iterate (tree, method_vec, slot, fn);
1701 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1706 resort_data.new_value = new_value;
1707 resort_data.cookie = cookie;
1708 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1709 resort_method_name_cmp);
1713 /* Warn about duplicate methods in fn_fields.
1715 Sort methods that are not special (i.e., constructors, destructors,
1716 and type conversion operators) so that we can find them faster in
1720 finish_struct_methods (tree t)
1723 VEC(tree,gc) *method_vec;
1726 method_vec = CLASSTYPE_METHOD_VEC (t);
1730 len = VEC_length (tree, method_vec);
1732 /* Clear DECL_IN_AGGR_P for all functions. */
1733 for (fn_fields = TYPE_METHODS (t); fn_fields;
1734 fn_fields = TREE_CHAIN (fn_fields))
1735 DECL_IN_AGGR_P (fn_fields) = 0;
1737 /* Issue warnings about private constructors and such. If there are
1738 no methods, then some public defaults are generated. */
1739 maybe_warn_about_overly_private_class (t);
1741 /* The type conversion ops have to live at the front of the vec, so we
1743 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1744 VEC_iterate (tree, method_vec, slot, fn_fields);
1746 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1749 qsort (VEC_address (tree, method_vec) + slot,
1750 len-slot, sizeof (tree), method_name_cmp);
1753 /* Make BINFO's vtable have N entries, including RTTI entries,
1754 vbase and vcall offsets, etc. Set its type and call the back end
1758 layout_vtable_decl (tree binfo, int n)
1763 atype = build_cplus_array_type (vtable_entry_type,
1764 build_index_type (size_int (n - 1)));
1765 layout_type (atype);
1767 /* We may have to grow the vtable. */
1768 vtable = get_vtbl_decl_for_binfo (binfo);
1769 if (!same_type_p (TREE_TYPE (vtable), atype))
1771 TREE_TYPE (vtable) = atype;
1772 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1773 layout_decl (vtable, 0);
1777 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1778 have the same signature. */
1781 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1783 /* One destructor overrides another if they are the same kind of
1785 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1786 && special_function_p (base_fndecl) == special_function_p (fndecl))
1788 /* But a non-destructor never overrides a destructor, nor vice
1789 versa, nor do different kinds of destructors override
1790 one-another. For example, a complete object destructor does not
1791 override a deleting destructor. */
1792 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1795 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1796 || (DECL_CONV_FN_P (fndecl)
1797 && DECL_CONV_FN_P (base_fndecl)
1798 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1799 DECL_CONV_FN_TYPE (base_fndecl))))
1801 tree types, base_types;
1802 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1803 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1804 if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1805 == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1806 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1812 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1816 base_derived_from (tree derived, tree base)
1820 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1822 if (probe == derived)
1824 else if (BINFO_VIRTUAL_P (probe))
1825 /* If we meet a virtual base, we can't follow the inheritance
1826 any more. See if the complete type of DERIVED contains
1827 such a virtual base. */
1828 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1834 typedef struct find_final_overrider_data_s {
1835 /* The function for which we are trying to find a final overrider. */
1837 /* The base class in which the function was declared. */
1838 tree declaring_base;
1839 /* The candidate overriders. */
1841 /* Path to most derived. */
1842 VEC(tree,heap) *path;
1843 } find_final_overrider_data;
1845 /* Add the overrider along the current path to FFOD->CANDIDATES.
1846 Returns true if an overrider was found; false otherwise. */
1849 dfs_find_final_overrider_1 (tree binfo,
1850 find_final_overrider_data *ffod,
1855 /* If BINFO is not the most derived type, try a more derived class.
1856 A definition there will overrider a definition here. */
1860 if (dfs_find_final_overrider_1
1861 (VEC_index (tree, ffod->path, depth), ffod, depth))
1865 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1868 tree *candidate = &ffod->candidates;
1870 /* Remove any candidates overridden by this new function. */
1873 /* If *CANDIDATE overrides METHOD, then METHOD
1874 cannot override anything else on the list. */
1875 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1877 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1878 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1879 *candidate = TREE_CHAIN (*candidate);
1881 candidate = &TREE_CHAIN (*candidate);
1884 /* Add the new function. */
1885 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1892 /* Called from find_final_overrider via dfs_walk. */
1895 dfs_find_final_overrider_pre (tree binfo, void *data)
1897 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1899 if (binfo == ffod->declaring_base)
1900 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1901 VEC_safe_push (tree, heap, ffod->path, binfo);
1907 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1909 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1910 VEC_pop (tree, ffod->path);
1915 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1916 FN and whose TREE_VALUE is the binfo for the base where the
1917 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1918 DERIVED) is the base object in which FN is declared. */
1921 find_final_overrider (tree derived, tree binfo, tree fn)
1923 find_final_overrider_data ffod;
1925 /* Getting this right is a little tricky. This is valid:
1927 struct S { virtual void f (); };
1928 struct T { virtual void f (); };
1929 struct U : public S, public T { };
1931 even though calling `f' in `U' is ambiguous. But,
1933 struct R { virtual void f(); };
1934 struct S : virtual public R { virtual void f (); };
1935 struct T : virtual public R { virtual void f (); };
1936 struct U : public S, public T { };
1938 is not -- there's no way to decide whether to put `S::f' or
1939 `T::f' in the vtable for `R'.
1941 The solution is to look at all paths to BINFO. If we find
1942 different overriders along any two, then there is a problem. */
1943 if (DECL_THUNK_P (fn))
1944 fn = THUNK_TARGET (fn);
1946 /* Determine the depth of the hierarchy. */
1948 ffod.declaring_base = binfo;
1949 ffod.candidates = NULL_TREE;
1950 ffod.path = VEC_alloc (tree, heap, 30);
1952 dfs_walk_all (derived, dfs_find_final_overrider_pre,
1953 dfs_find_final_overrider_post, &ffod);
1955 VEC_free (tree, heap, ffod.path);
1957 /* If there was no winner, issue an error message. */
1958 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
1959 return error_mark_node;
1961 return ffod.candidates;
1964 /* Return the index of the vcall offset for FN when TYPE is used as a
1968 get_vcall_index (tree fn, tree type)
1970 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
1974 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
1975 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
1976 || same_signature_p (fn, p->purpose))
1979 /* There should always be an appropriate index. */
1983 /* Update an entry in the vtable for BINFO, which is in the hierarchy
1984 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
1985 corresponding position in the BINFO_VIRTUALS list. */
1988 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
1996 tree overrider_fn, overrider_target;
1997 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
1998 tree over_return, base_return;
2001 /* Find the nearest primary base (possibly binfo itself) which defines
2002 this function; this is the class the caller will convert to when
2003 calling FN through BINFO. */
2004 for (b = binfo; ; b = get_primary_binfo (b))
2007 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2010 /* The nearest definition is from a lost primary. */
2011 if (BINFO_LOST_PRIMARY_P (b))
2016 /* Find the final overrider. */
2017 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2018 if (overrider == error_mark_node)
2020 error ("no unique final overrider for %qD in %qT", target_fn, t);
2023 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2025 /* Check for adjusting covariant return types. */
2026 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2027 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2029 if (POINTER_TYPE_P (over_return)
2030 && TREE_CODE (over_return) == TREE_CODE (base_return)
2031 && CLASS_TYPE_P (TREE_TYPE (over_return))
2032 && CLASS_TYPE_P (TREE_TYPE (base_return))
2033 /* If the overrider is invalid, don't even try. */
2034 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2036 /* If FN is a covariant thunk, we must figure out the adjustment
2037 to the final base FN was converting to. As OVERRIDER_TARGET might
2038 also be converting to the return type of FN, we have to
2039 combine the two conversions here. */
2040 tree fixed_offset, virtual_offset;
2042 over_return = TREE_TYPE (over_return);
2043 base_return = TREE_TYPE (base_return);
2045 if (DECL_THUNK_P (fn))
2047 gcc_assert (DECL_RESULT_THUNK_P (fn));
2048 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2049 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2052 fixed_offset = virtual_offset = NULL_TREE;
2055 /* Find the equivalent binfo within the return type of the
2056 overriding function. We will want the vbase offset from
2058 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2060 else if (!same_type_ignoring_top_level_qualifiers_p
2061 (over_return, base_return))
2063 /* There was no existing virtual thunk (which takes
2064 precedence). So find the binfo of the base function's
2065 return type within the overriding function's return type.
2066 We cannot call lookup base here, because we're inside a
2067 dfs_walk, and will therefore clobber the BINFO_MARKED
2068 flags. Fortunately we know the covariancy is valid (it
2069 has already been checked), so we can just iterate along
2070 the binfos, which have been chained in inheritance graph
2071 order. Of course it is lame that we have to repeat the
2072 search here anyway -- we should really be caching pieces
2073 of the vtable and avoiding this repeated work. */
2074 tree thunk_binfo, base_binfo;
2076 /* Find the base binfo within the overriding function's
2077 return type. We will always find a thunk_binfo, except
2078 when the covariancy is invalid (which we will have
2079 already diagnosed). */
2080 for (base_binfo = TYPE_BINFO (base_return),
2081 thunk_binfo = TYPE_BINFO (over_return);
2083 thunk_binfo = TREE_CHAIN (thunk_binfo))
2084 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2085 BINFO_TYPE (base_binfo)))
2088 /* See if virtual inheritance is involved. */
2089 for (virtual_offset = thunk_binfo;
2091 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2092 if (BINFO_VIRTUAL_P (virtual_offset))
2096 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2098 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2102 /* We convert via virtual base. Adjust the fixed
2103 offset to be from there. */
2104 offset = size_diffop
2106 (ssizetype, BINFO_OFFSET (virtual_offset)));
2109 /* There was an existing fixed offset, this must be
2110 from the base just converted to, and the base the
2111 FN was thunking to. */
2112 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2114 fixed_offset = offset;
2118 if (fixed_offset || virtual_offset)
2119 /* Replace the overriding function with a covariant thunk. We
2120 will emit the overriding function in its own slot as
2122 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2123 fixed_offset, virtual_offset);
2126 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2127 !DECL_THUNK_P (fn));
2129 /* Assume that we will produce a thunk that convert all the way to
2130 the final overrider, and not to an intermediate virtual base. */
2131 virtual_base = NULL_TREE;
2133 /* See if we can convert to an intermediate virtual base first, and then
2134 use the vcall offset located there to finish the conversion. */
2135 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2137 /* If we find the final overrider, then we can stop
2139 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2140 BINFO_TYPE (TREE_VALUE (overrider))))
2143 /* If we find a virtual base, and we haven't yet found the
2144 overrider, then there is a virtual base between the
2145 declaring base (first_defn) and the final overrider. */
2146 if (BINFO_VIRTUAL_P (b))
2153 if (overrider_fn != overrider_target && !virtual_base)
2155 /* The ABI specifies that a covariant thunk includes a mangling
2156 for a this pointer adjustment. This-adjusting thunks that
2157 override a function from a virtual base have a vcall
2158 adjustment. When the virtual base in question is a primary
2159 virtual base, we know the adjustments are zero, (and in the
2160 non-covariant case, we would not use the thunk).
2161 Unfortunately we didn't notice this could happen, when
2162 designing the ABI and so never mandated that such a covariant
2163 thunk should be emitted. Because we must use the ABI mandated
2164 name, we must continue searching from the binfo where we
2165 found the most recent definition of the function, towards the
2166 primary binfo which first introduced the function into the
2167 vtable. If that enters a virtual base, we must use a vcall
2168 this-adjusting thunk. Bleah! */
2169 tree probe = first_defn;
2171 while ((probe = get_primary_binfo (probe))
2172 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2173 if (BINFO_VIRTUAL_P (probe))
2174 virtual_base = probe;
2177 /* Even if we find a virtual base, the correct delta is
2178 between the overrider and the binfo we're building a vtable
2180 goto virtual_covariant;
2183 /* Compute the constant adjustment to the `this' pointer. The
2184 `this' pointer, when this function is called, will point at BINFO
2185 (or one of its primary bases, which are at the same offset). */
2187 /* The `this' pointer needs to be adjusted from the declaration to
2188 the nearest virtual base. */
2189 delta = size_diffop (convert (ssizetype, BINFO_OFFSET (virtual_base)),
2190 convert (ssizetype, BINFO_OFFSET (first_defn)));
2192 /* If the nearest definition is in a lost primary, we don't need an
2193 entry in our vtable. Except possibly in a constructor vtable,
2194 if we happen to get our primary back. In that case, the offset
2195 will be zero, as it will be a primary base. */
2196 delta = size_zero_node;
2198 /* The `this' pointer needs to be adjusted from pointing to
2199 BINFO to pointing at the base where the final overrider
2202 delta = size_diffop (convert (ssizetype,
2203 BINFO_OFFSET (TREE_VALUE (overrider))),
2204 convert (ssizetype, BINFO_OFFSET (binfo)));
2206 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2209 BV_VCALL_INDEX (*virtuals)
2210 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2212 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2215 /* Called from modify_all_vtables via dfs_walk. */
2218 dfs_modify_vtables (tree binfo, void* data)
2220 tree t = (tree) data;
2225 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2226 /* A base without a vtable needs no modification, and its bases
2227 are uninteresting. */
2228 return dfs_skip_bases;
2230 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2231 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2232 /* Don't do the primary vtable, if it's new. */
2235 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2236 /* There's no need to modify the vtable for a non-virtual primary
2237 base; we're not going to use that vtable anyhow. We do still
2238 need to do this for virtual primary bases, as they could become
2239 non-primary in a construction vtable. */
2242 make_new_vtable (t, binfo);
2244 /* Now, go through each of the virtual functions in the virtual
2245 function table for BINFO. Find the final overrider, and update
2246 the BINFO_VIRTUALS list appropriately. */
2247 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2248 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2250 ix++, virtuals = TREE_CHAIN (virtuals),
2251 old_virtuals = TREE_CHAIN (old_virtuals))
2252 update_vtable_entry_for_fn (t,
2254 BV_FN (old_virtuals),
2260 /* Update all of the primary and secondary vtables for T. Create new
2261 vtables as required, and initialize their RTTI information. Each
2262 of the functions in VIRTUALS is declared in T and may override a
2263 virtual function from a base class; find and modify the appropriate
2264 entries to point to the overriding functions. Returns a list, in
2265 declaration order, of the virtual functions that are declared in T,
2266 but do not appear in the primary base class vtable, and which
2267 should therefore be appended to the end of the vtable for T. */
2270 modify_all_vtables (tree t, tree virtuals)
2272 tree binfo = TYPE_BINFO (t);
2275 /* Update all of the vtables. */
2276 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2278 /* Add virtual functions not already in our primary vtable. These
2279 will be both those introduced by this class, and those overridden
2280 from secondary bases. It does not include virtuals merely
2281 inherited from secondary bases. */
2282 for (fnsp = &virtuals; *fnsp; )
2284 tree fn = TREE_VALUE (*fnsp);
2286 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2287 || DECL_VINDEX (fn) == error_mark_node)
2289 /* We don't need to adjust the `this' pointer when
2290 calling this function. */
2291 BV_DELTA (*fnsp) = integer_zero_node;
2292 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2294 /* This is a function not already in our vtable. Keep it. */
2295 fnsp = &TREE_CHAIN (*fnsp);
2298 /* We've already got an entry for this function. Skip it. */
2299 *fnsp = TREE_CHAIN (*fnsp);
2305 /* Get the base virtual function declarations in T that have the
2309 get_basefndecls (tree name, tree t)
2312 tree base_fndecls = NULL_TREE;
2313 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2316 /* Find virtual functions in T with the indicated NAME. */
2317 i = lookup_fnfields_1 (t, name);
2319 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2321 methods = OVL_NEXT (methods))
2323 tree method = OVL_CURRENT (methods);
2325 if (TREE_CODE (method) == FUNCTION_DECL
2326 && DECL_VINDEX (method))
2327 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2331 return base_fndecls;
2333 for (i = 0; i < n_baseclasses; i++)
2335 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2336 base_fndecls = chainon (get_basefndecls (name, basetype),
2340 return base_fndecls;
2343 /* If this declaration supersedes the declaration of
2344 a method declared virtual in the base class, then
2345 mark this field as being virtual as well. */
2348 check_for_override (tree decl, tree ctype)
2350 if (TREE_CODE (decl) == TEMPLATE_DECL)
2351 /* In [temp.mem] we have:
2353 A specialization of a member function template does not
2354 override a virtual function from a base class. */
2356 if ((DECL_DESTRUCTOR_P (decl)
2357 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2358 || DECL_CONV_FN_P (decl))
2359 && look_for_overrides (ctype, decl)
2360 && !DECL_STATIC_FUNCTION_P (decl))
2361 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2362 the error_mark_node so that we know it is an overriding
2364 DECL_VINDEX (decl) = decl;
2366 if (DECL_VIRTUAL_P (decl))
2368 if (!DECL_VINDEX (decl))
2369 DECL_VINDEX (decl) = error_mark_node;
2370 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2374 /* Warn about hidden virtual functions that are not overridden in t.
2375 We know that constructors and destructors don't apply. */
2378 warn_hidden (tree t)
2380 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2384 /* We go through each separately named virtual function. */
2385 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2386 VEC_iterate (tree, method_vec, i, fns);
2397 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2398 have the same name. Figure out what name that is. */
2399 name = DECL_NAME (OVL_CURRENT (fns));
2400 /* There are no possibly hidden functions yet. */
2401 base_fndecls = NULL_TREE;
2402 /* Iterate through all of the base classes looking for possibly
2403 hidden functions. */
2404 for (binfo = TYPE_BINFO (t), j = 0;
2405 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2407 tree basetype = BINFO_TYPE (base_binfo);
2408 base_fndecls = chainon (get_basefndecls (name, basetype),
2412 /* If there are no functions to hide, continue. */
2416 /* Remove any overridden functions. */
2417 for (fn = fns; fn; fn = OVL_NEXT (fn))
2419 fndecl = OVL_CURRENT (fn);
2420 if (DECL_VINDEX (fndecl))
2422 tree *prev = &base_fndecls;
2425 /* If the method from the base class has the same
2426 signature as the method from the derived class, it
2427 has been overridden. */
2428 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2429 *prev = TREE_CHAIN (*prev);
2431 prev = &TREE_CHAIN (*prev);
2435 /* Now give a warning for all base functions without overriders,
2436 as they are hidden. */
2437 while (base_fndecls)
2439 /* Here we know it is a hider, and no overrider exists. */
2440 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2441 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2442 base_fndecls = TREE_CHAIN (base_fndecls);
2447 /* Check for things that are invalid. There are probably plenty of other
2448 things we should check for also. */
2451 finish_struct_anon (tree t)
2455 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2457 if (TREE_STATIC (field))
2459 if (TREE_CODE (field) != FIELD_DECL)
2462 if (DECL_NAME (field) == NULL_TREE
2463 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2465 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2466 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2467 for (; elt; elt = TREE_CHAIN (elt))
2469 /* We're generally only interested in entities the user
2470 declared, but we also find nested classes by noticing
2471 the TYPE_DECL that we create implicitly. You're
2472 allowed to put one anonymous union inside another,
2473 though, so we explicitly tolerate that. We use
2474 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2475 we also allow unnamed types used for defining fields. */
2476 if (DECL_ARTIFICIAL (elt)
2477 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2478 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2481 if (TREE_CODE (elt) != FIELD_DECL)
2484 pedwarn ("%q+#D invalid; an anonymous union can "
2485 "only have non-static data members", elt);
2487 pedwarn ("%q+#D invalid; an anonymous struct can "
2488 "only have non-static data members", elt);
2492 if (TREE_PRIVATE (elt))
2495 pedwarn ("private member %q+#D in anonymous union", elt);
2497 pedwarn ("private member %q+#D in anonymous struct", elt);
2499 else if (TREE_PROTECTED (elt))
2502 pedwarn ("protected member %q+#D in anonymous union", elt);
2504 pedwarn ("protected member %q+#D in anonymous struct", elt);
2507 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2508 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2514 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2515 will be used later during class template instantiation.
2516 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2517 a non-static member data (FIELD_DECL), a member function
2518 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2519 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2520 When FRIEND_P is nonzero, T is either a friend class
2521 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2522 (FUNCTION_DECL, TEMPLATE_DECL). */
2525 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2527 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2528 if (CLASSTYPE_TEMPLATE_INFO (type))
2529 CLASSTYPE_DECL_LIST (type)
2530 = tree_cons (friend_p ? NULL_TREE : type,
2531 t, CLASSTYPE_DECL_LIST (type));
2534 /* Create default constructors, assignment operators, and so forth for
2535 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2536 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2537 the class cannot have a default constructor, copy constructor
2538 taking a const reference argument, or an assignment operator taking
2539 a const reference, respectively. */
2542 add_implicitly_declared_members (tree t,
2543 int cant_have_const_cctor,
2544 int cant_have_const_assignment)
2547 if (!CLASSTYPE_DESTRUCTORS (t))
2549 /* In general, we create destructors lazily. */
2550 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2551 /* However, if the implicit destructor is non-trivial
2552 destructor, we sometimes have to create it at this point. */
2553 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2557 if (TYPE_FOR_JAVA (t))
2558 /* If this a Java class, any non-trivial destructor is
2559 invalid, even if compiler-generated. Therefore, if the
2560 destructor is non-trivial we create it now. */
2568 /* If the implicit destructor will be virtual, then we must
2569 generate it now because (unfortunately) we do not
2570 generate virtual tables lazily. */
2571 binfo = TYPE_BINFO (t);
2572 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2577 base_type = BINFO_TYPE (base_binfo);
2578 dtor = CLASSTYPE_DESTRUCTORS (base_type);
2579 if (dtor && DECL_VIRTUAL_P (dtor))
2587 /* If we can't get away with being lazy, generate the destructor
2590 lazily_declare_fn (sfk_destructor, t);
2594 /* Default constructor. */
2595 if (! TYPE_HAS_CONSTRUCTOR (t))
2597 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2598 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2601 /* Copy constructor. */
2602 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2604 TYPE_HAS_INIT_REF (t) = 1;
2605 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2606 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2607 TYPE_HAS_CONSTRUCTOR (t) = 1;
2610 /* If there is no assignment operator, one will be created if and
2611 when it is needed. For now, just record whether or not the type
2612 of the parameter to the assignment operator will be a const or
2613 non-const reference. */
2614 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2616 TYPE_HAS_ASSIGN_REF (t) = 1;
2617 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2618 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2622 /* Subroutine of finish_struct_1. Recursively count the number of fields
2623 in TYPE, including anonymous union members. */
2626 count_fields (tree fields)
2630 for (x = fields; x; x = TREE_CHAIN (x))
2632 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2633 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2640 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2641 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2644 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2647 for (x = fields; x; x = TREE_CHAIN (x))
2649 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2650 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2652 field_vec->elts[idx++] = x;
2657 /* FIELD is a bit-field. We are finishing the processing for its
2658 enclosing type. Issue any appropriate messages and set appropriate
2659 flags. Returns false if an error has been diagnosed. */
2662 check_bitfield_decl (tree field)
2664 tree type = TREE_TYPE (field);
2667 /* Extract the declared width of the bitfield, which has been
2668 temporarily stashed in DECL_INITIAL. */
2669 w = DECL_INITIAL (field);
2670 gcc_assert (w != NULL_TREE);
2671 /* Remove the bit-field width indicator so that the rest of the
2672 compiler does not treat that value as an initializer. */
2673 DECL_INITIAL (field) = NULL_TREE;
2675 /* Detect invalid bit-field type. */
2676 if (!INTEGRAL_TYPE_P (type))
2678 error ("bit-field %q+#D with non-integral type", field);
2679 w = error_mark_node;
2683 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2686 /* detect invalid field size. */
2687 w = integral_constant_value (w);
2689 if (TREE_CODE (w) != INTEGER_CST)
2691 error ("bit-field %q+D width not an integer constant", field);
2692 w = error_mark_node;
2694 else if (tree_int_cst_sgn (w) < 0)
2696 error ("negative width in bit-field %q+D", field);
2697 w = error_mark_node;
2699 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2701 error ("zero width for bit-field %q+D", field);
2702 w = error_mark_node;
2704 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2705 && TREE_CODE (type) != ENUMERAL_TYPE
2706 && TREE_CODE (type) != BOOLEAN_TYPE)
2707 warning (0, "width of %q+D exceeds its type", field);
2708 else if (TREE_CODE (type) == ENUMERAL_TYPE
2709 && (0 > compare_tree_int (w,
2710 min_precision (TYPE_MIN_VALUE (type),
2711 TYPE_UNSIGNED (type)))
2712 || 0 > compare_tree_int (w,
2714 (TYPE_MAX_VALUE (type),
2715 TYPE_UNSIGNED (type)))))
2716 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2719 if (w != error_mark_node)
2721 DECL_SIZE (field) = convert (bitsizetype, w);
2722 DECL_BIT_FIELD (field) = 1;
2727 /* Non-bit-fields are aligned for their type. */
2728 DECL_BIT_FIELD (field) = 0;
2729 CLEAR_DECL_C_BIT_FIELD (field);
2734 /* FIELD is a non bit-field. We are finishing the processing for its
2735 enclosing type T. Issue any appropriate messages and set appropriate
2739 check_field_decl (tree field,
2741 int* cant_have_const_ctor,
2742 int* no_const_asn_ref,
2743 int* any_default_members)
2745 tree type = strip_array_types (TREE_TYPE (field));
2747 /* An anonymous union cannot contain any fields which would change
2748 the settings of CANT_HAVE_CONST_CTOR and friends. */
2749 if (ANON_UNION_TYPE_P (type))
2751 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2752 structs. So, we recurse through their fields here. */
2753 else if (ANON_AGGR_TYPE_P (type))
2757 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2758 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2759 check_field_decl (fields, t, cant_have_const_ctor,
2760 no_const_asn_ref, any_default_members);
2762 /* Check members with class type for constructors, destructors,
2764 else if (CLASS_TYPE_P (type))
2766 /* Never let anything with uninheritable virtuals
2767 make it through without complaint. */
2768 abstract_virtuals_error (field, type);
2770 if (TREE_CODE (t) == UNION_TYPE)
2772 if (TYPE_NEEDS_CONSTRUCTING (type))
2773 error ("member %q+#D with constructor not allowed in union",
2775 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2776 error ("member %q+#D with destructor not allowed in union", field);
2777 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2778 error ("member %q+#D with copy assignment operator not allowed in union",
2783 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2784 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2785 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2786 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2787 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2788 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (type);
2791 if (!TYPE_HAS_CONST_INIT_REF (type))
2792 *cant_have_const_ctor = 1;
2794 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2795 *no_const_asn_ref = 1;
2797 if (DECL_INITIAL (field) != NULL_TREE)
2799 /* `build_class_init_list' does not recognize
2801 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2802 error ("multiple fields in union %qT initialized", t);
2803 *any_default_members = 1;
2807 /* Check the data members (both static and non-static), class-scoped
2808 typedefs, etc., appearing in the declaration of T. Issue
2809 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2810 declaration order) of access declarations; each TREE_VALUE in this
2811 list is a USING_DECL.
2813 In addition, set the following flags:
2816 The class is empty, i.e., contains no non-static data members.
2818 CANT_HAVE_CONST_CTOR_P
2819 This class cannot have an implicitly generated copy constructor
2820 taking a const reference.
2822 CANT_HAVE_CONST_ASN_REF
2823 This class cannot have an implicitly generated assignment
2824 operator taking a const reference.
2826 All of these flags should be initialized before calling this
2829 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2830 fields can be added by adding to this chain. */
2833 check_field_decls (tree t, tree *access_decls,
2834 int *cant_have_const_ctor_p,
2835 int *no_const_asn_ref_p)
2840 int any_default_members;
2843 /* Assume there are no access declarations. */
2844 *access_decls = NULL_TREE;
2845 /* Assume this class has no pointer members. */
2846 has_pointers = false;
2847 /* Assume none of the members of this class have default
2849 any_default_members = 0;
2851 for (field = &TYPE_FIELDS (t); *field; field = next)
2854 tree type = TREE_TYPE (x);
2856 next = &TREE_CHAIN (x);
2858 if (TREE_CODE (x) == USING_DECL)
2860 /* Prune the access declaration from the list of fields. */
2861 *field = TREE_CHAIN (x);
2863 /* Save the access declarations for our caller. */
2864 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2866 /* Since we've reset *FIELD there's no reason to skip to the
2872 if (TREE_CODE (x) == TYPE_DECL
2873 || TREE_CODE (x) == TEMPLATE_DECL)
2876 /* If we've gotten this far, it's a data member, possibly static,
2877 or an enumerator. */
2878 DECL_CONTEXT (x) = t;
2880 /* When this goes into scope, it will be a non-local reference. */
2881 DECL_NONLOCAL (x) = 1;
2883 if (TREE_CODE (t) == UNION_TYPE)
2887 If a union contains a static data member, or a member of
2888 reference type, the program is ill-formed. */
2889 if (TREE_CODE (x) == VAR_DECL)
2891 error ("%q+D may not be static because it is a member of a union", x);
2894 if (TREE_CODE (type) == REFERENCE_TYPE)
2896 error ("%q+D may not have reference type %qT because"
2897 " it is a member of a union",
2903 /* Perform error checking that did not get done in
2905 if (TREE_CODE (type) == FUNCTION_TYPE)
2907 error ("field %q+D invalidly declared function type", x);
2908 type = build_pointer_type (type);
2909 TREE_TYPE (x) = type;
2911 else if (TREE_CODE (type) == METHOD_TYPE)
2913 error ("field %q+D invalidly declared method type", x);
2914 type = build_pointer_type (type);
2915 TREE_TYPE (x) = type;
2918 if (type == error_mark_node)
2921 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
2924 /* Now it can only be a FIELD_DECL. */
2926 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
2927 CLASSTYPE_NON_AGGREGATE (t) = 1;
2929 /* If this is of reference type, check if it needs an init.
2930 Also do a little ANSI jig if necessary. */
2931 if (TREE_CODE (type) == REFERENCE_TYPE)
2933 CLASSTYPE_NON_POD_P (t) = 1;
2934 if (DECL_INITIAL (x) == NULL_TREE)
2935 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2937 /* ARM $12.6.2: [A member initializer list] (or, for an
2938 aggregate, initialization by a brace-enclosed list) is the
2939 only way to initialize nonstatic const and reference
2941 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2943 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
2945 warning (OPT_Wextra, "non-static reference %q+#D in class without a constructor", x);
2948 type = strip_array_types (type);
2950 if (TYPE_PACKED (t))
2952 if (!pod_type_p (type) && !TYPE_PACKED (type))
2956 "ignoring packed attribute because of unpacked non-POD field %q+#D",
2960 else if (TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
2961 DECL_PACKED (x) = 1;
2964 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
2965 /* We don't treat zero-width bitfields as making a class
2970 /* The class is non-empty. */
2971 CLASSTYPE_EMPTY_P (t) = 0;
2972 /* The class is not even nearly empty. */
2973 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
2974 /* If one of the data members contains an empty class,
2976 if (CLASS_TYPE_P (type)
2977 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
2978 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
2981 /* This is used by -Weffc++ (see below). Warn only for pointers
2982 to members which might hold dynamic memory. So do not warn
2983 for pointers to functions or pointers to members. */
2984 if (TYPE_PTR_P (type)
2985 && !TYPE_PTRFN_P (type)
2986 && !TYPE_PTR_TO_MEMBER_P (type))
2987 has_pointers = true;
2989 if (CLASS_TYPE_P (type))
2991 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
2992 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2993 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
2994 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
2997 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
2998 CLASSTYPE_HAS_MUTABLE (t) = 1;
3000 if (! pod_type_p (type))
3001 /* DR 148 now allows pointers to members (which are POD themselves),
3002 to be allowed in POD structs. */
3003 CLASSTYPE_NON_POD_P (t) = 1;
3005 if (! zero_init_p (type))
3006 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3008 /* If any field is const, the structure type is pseudo-const. */
3009 if (CP_TYPE_CONST_P (type))
3011 C_TYPE_FIELDS_READONLY (t) = 1;
3012 if (DECL_INITIAL (x) == NULL_TREE)
3013 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3015 /* ARM $12.6.2: [A member initializer list] (or, for an
3016 aggregate, initialization by a brace-enclosed list) is the
3017 only way to initialize nonstatic const and reference
3019 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3021 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
3023 warning (OPT_Wextra, "non-static const member %q+#D in class without a constructor", x);
3025 /* A field that is pseudo-const makes the structure likewise. */
3026 else if (CLASS_TYPE_P (type))
3028 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3029 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3030 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3031 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3034 /* Core issue 80: A nonstatic data member is required to have a
3035 different name from the class iff the class has a
3036 user-defined constructor. */
3037 if (constructor_name_p (DECL_NAME (x), t) && TYPE_HAS_CONSTRUCTOR (t))
3038 pedwarn ("field %q+#D with same name as class", x);
3040 /* We set DECL_C_BIT_FIELD in grokbitfield.
3041 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3042 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3043 check_field_decl (x, t,
3044 cant_have_const_ctor_p,
3046 &any_default_members);
3049 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3050 it should also define a copy constructor and an assignment operator to
3051 implement the correct copy semantic (deep vs shallow, etc.). As it is
3052 not feasible to check whether the constructors do allocate dynamic memory
3053 and store it within members, we approximate the warning like this:
3055 -- Warn only if there are members which are pointers
3056 -- Warn only if there is a non-trivial constructor (otherwise,
3057 there cannot be memory allocated).
3058 -- Warn only if there is a non-trivial destructor. We assume that the
3059 user at least implemented the cleanup correctly, and a destructor
3060 is needed to free dynamic memory.
3062 This seems enough for practical purposes. */
3065 && TYPE_HAS_CONSTRUCTOR (t)
3066 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3067 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3069 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3071 if (! TYPE_HAS_INIT_REF (t))
3073 warning (OPT_Weffc__,
3074 " but does not override %<%T(const %T&)%>", t, t);
3075 if (!TYPE_HAS_ASSIGN_REF (t))
3076 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3078 else if (! TYPE_HAS_ASSIGN_REF (t))
3079 warning (OPT_Weffc__,
3080 " but does not override %<operator=(const %T&)%>", t);
3083 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3085 TYPE_PACKED (t) = 0;
3087 /* Check anonymous struct/anonymous union fields. */
3088 finish_struct_anon (t);
3090 /* We've built up the list of access declarations in reverse order.
3092 *access_decls = nreverse (*access_decls);
3095 /* If TYPE is an empty class type, records its OFFSET in the table of
3099 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3103 if (!is_empty_class (type))
3106 /* Record the location of this empty object in OFFSETS. */
3107 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3109 n = splay_tree_insert (offsets,
3110 (splay_tree_key) offset,
3111 (splay_tree_value) NULL_TREE);
3112 n->value = ((splay_tree_value)
3113 tree_cons (NULL_TREE,
3120 /* Returns nonzero if TYPE is an empty class type and there is
3121 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3124 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3129 if (!is_empty_class (type))
3132 /* Record the location of this empty object in OFFSETS. */
3133 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3137 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3138 if (same_type_p (TREE_VALUE (t), type))
3144 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3145 F for every subobject, passing it the type, offset, and table of
3146 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3149 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3150 than MAX_OFFSET will not be walked.
3152 If F returns a nonzero value, the traversal ceases, and that value
3153 is returned. Otherwise, returns zero. */
3156 walk_subobject_offsets (tree type,
3157 subobject_offset_fn f,
3164 tree type_binfo = NULL_TREE;
3166 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3168 if (max_offset && INT_CST_LT (max_offset, offset))
3171 if (type == error_mark_node)
3176 if (abi_version_at_least (2))
3178 type = BINFO_TYPE (type);
3181 if (CLASS_TYPE_P (type))
3187 /* Avoid recursing into objects that are not interesting. */
3188 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3191 /* Record the location of TYPE. */
3192 r = (*f) (type, offset, offsets);
3196 /* Iterate through the direct base classes of TYPE. */
3198 type_binfo = TYPE_BINFO (type);
3199 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3203 if (abi_version_at_least (2)
3204 && BINFO_VIRTUAL_P (binfo))
3208 && BINFO_VIRTUAL_P (binfo)
3209 && !BINFO_PRIMARY_P (binfo))
3212 if (!abi_version_at_least (2))
3213 binfo_offset = size_binop (PLUS_EXPR,
3215 BINFO_OFFSET (binfo));
3219 /* We cannot rely on BINFO_OFFSET being set for the base
3220 class yet, but the offsets for direct non-virtual
3221 bases can be calculated by going back to the TYPE. */
3222 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3223 binfo_offset = size_binop (PLUS_EXPR,
3225 BINFO_OFFSET (orig_binfo));
3228 r = walk_subobject_offsets (binfo,
3233 (abi_version_at_least (2)
3234 ? /*vbases_p=*/0 : vbases_p));
3239 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3242 VEC(tree,gc) *vbases;
3244 /* Iterate through the virtual base classes of TYPE. In G++
3245 3.2, we included virtual bases in the direct base class
3246 loop above, which results in incorrect results; the
3247 correct offsets for virtual bases are only known when
3248 working with the most derived type. */
3250 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3251 VEC_iterate (tree, vbases, ix, binfo); ix++)
3253 r = walk_subobject_offsets (binfo,
3255 size_binop (PLUS_EXPR,
3257 BINFO_OFFSET (binfo)),
3266 /* We still have to walk the primary base, if it is
3267 virtual. (If it is non-virtual, then it was walked
3269 tree vbase = get_primary_binfo (type_binfo);
3271 if (vbase && BINFO_VIRTUAL_P (vbase)
3272 && BINFO_PRIMARY_P (vbase)
3273 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3275 r = (walk_subobject_offsets
3277 offsets, max_offset, /*vbases_p=*/0));
3284 /* Iterate through the fields of TYPE. */
3285 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3286 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3290 if (abi_version_at_least (2))
3291 field_offset = byte_position (field);
3293 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3294 field_offset = DECL_FIELD_OFFSET (field);
3296 r = walk_subobject_offsets (TREE_TYPE (field),
3298 size_binop (PLUS_EXPR,
3308 else if (TREE_CODE (type) == ARRAY_TYPE)
3310 tree element_type = strip_array_types (type);
3311 tree domain = TYPE_DOMAIN (type);
3314 /* Avoid recursing into objects that are not interesting. */
3315 if (!CLASS_TYPE_P (element_type)
3316 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3319 /* Step through each of the elements in the array. */
3320 for (index = size_zero_node;
3321 /* G++ 3.2 had an off-by-one error here. */
3322 (abi_version_at_least (2)
3323 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3324 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3325 index = size_binop (PLUS_EXPR, index, size_one_node))
3327 r = walk_subobject_offsets (TREE_TYPE (type),
3335 offset = size_binop (PLUS_EXPR, offset,
3336 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3337 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3338 there's no point in iterating through the remaining
3339 elements of the array. */
3340 if (max_offset && INT_CST_LT (max_offset, offset))
3348 /* Record all of the empty subobjects of TYPE (either a type or a
3349 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3350 is being placed at OFFSET; otherwise, it is a base class that is
3351 being placed at OFFSET. */
3354 record_subobject_offsets (tree type,
3357 bool is_data_member)
3360 /* If recording subobjects for a non-static data member or a
3361 non-empty base class , we do not need to record offsets beyond
3362 the size of the biggest empty class. Additional data members
3363 will go at the end of the class. Additional base classes will go
3364 either at offset zero (if empty, in which case they cannot
3365 overlap with offsets past the size of the biggest empty class) or
3366 at the end of the class.
3368 However, if we are placing an empty base class, then we must record
3369 all offsets, as either the empty class is at offset zero (where
3370 other empty classes might later be placed) or at the end of the
3371 class (where other objects might then be placed, so other empty
3372 subobjects might later overlap). */
3374 || !is_empty_class (BINFO_TYPE (type)))
3375 max_offset = sizeof_biggest_empty_class;
3377 max_offset = NULL_TREE;
3378 walk_subobject_offsets (type, record_subobject_offset, offset,
3379 offsets, max_offset, is_data_member);
3382 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3383 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3384 virtual bases of TYPE are examined. */
3387 layout_conflict_p (tree type,
3392 splay_tree_node max_node;
3394 /* Get the node in OFFSETS that indicates the maximum offset where
3395 an empty subobject is located. */
3396 max_node = splay_tree_max (offsets);
3397 /* If there aren't any empty subobjects, then there's no point in
3398 performing this check. */
3402 return walk_subobject_offsets (type, check_subobject_offset, offset,
3403 offsets, (tree) (max_node->key),
3407 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3408 non-static data member of the type indicated by RLI. BINFO is the
3409 binfo corresponding to the base subobject, OFFSETS maps offsets to
3410 types already located at those offsets. This function determines
3411 the position of the DECL. */
3414 layout_nonempty_base_or_field (record_layout_info rli,
3419 tree offset = NULL_TREE;
3425 /* For the purposes of determining layout conflicts, we want to
3426 use the class type of BINFO; TREE_TYPE (DECL) will be the
3427 CLASSTYPE_AS_BASE version, which does not contain entries for
3428 zero-sized bases. */
3429 type = TREE_TYPE (binfo);
3434 type = TREE_TYPE (decl);
3438 /* Try to place the field. It may take more than one try if we have
3439 a hard time placing the field without putting two objects of the
3440 same type at the same address. */
3443 struct record_layout_info_s old_rli = *rli;
3445 /* Place this field. */
3446 place_field (rli, decl);
3447 offset = byte_position (decl);
3449 /* We have to check to see whether or not there is already
3450 something of the same type at the offset we're about to use.
3451 For example, consider:
3454 struct T : public S { int i; };
3455 struct U : public S, public T {};
3457 Here, we put S at offset zero in U. Then, we can't put T at
3458 offset zero -- its S component would be at the same address
3459 as the S we already allocated. So, we have to skip ahead.
3460 Since all data members, including those whose type is an
3461 empty class, have nonzero size, any overlap can happen only
3462 with a direct or indirect base-class -- it can't happen with
3464 /* In a union, overlap is permitted; all members are placed at
3466 if (TREE_CODE (rli->t) == UNION_TYPE)
3468 /* G++ 3.2 did not check for overlaps when placing a non-empty
3470 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3472 if (layout_conflict_p (field_p ? type : binfo, offset,
3475 /* Strip off the size allocated to this field. That puts us
3476 at the first place we could have put the field with
3477 proper alignment. */
3480 /* Bump up by the alignment required for the type. */
3482 = size_binop (PLUS_EXPR, rli->bitpos,
3484 ? CLASSTYPE_ALIGN (type)
3485 : TYPE_ALIGN (type)));
3486 normalize_rli (rli);
3489 /* There was no conflict. We're done laying out this field. */
3493 /* Now that we know where it will be placed, update its
3495 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3496 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3497 this point because their BINFO_OFFSET is copied from another
3498 hierarchy. Therefore, we may not need to add the entire
3500 propagate_binfo_offsets (binfo,
3501 size_diffop (convert (ssizetype, offset),
3503 BINFO_OFFSET (binfo))));
3506 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3509 empty_base_at_nonzero_offset_p (tree type,
3511 splay_tree offsets ATTRIBUTE_UNUSED)
3513 return is_empty_class (type) && !integer_zerop (offset);
3516 /* Layout the empty base BINFO. EOC indicates the byte currently just
3517 past the end of the class, and should be correctly aligned for a
3518 class of the type indicated by BINFO; OFFSETS gives the offsets of
3519 the empty bases allocated so far. T is the most derived
3520 type. Return nonzero iff we added it at the end. */
3523 layout_empty_base (record_layout_info rli, tree binfo,
3524 tree eoc, splay_tree offsets)
3527 tree basetype = BINFO_TYPE (binfo);
3530 /* This routine should only be used for empty classes. */
3531 gcc_assert (is_empty_class (basetype));
3532 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3534 if (!integer_zerop (BINFO_OFFSET (binfo)))
3536 if (abi_version_at_least (2))
3537 propagate_binfo_offsets
3538 (binfo, size_diffop (size_zero_node, BINFO_OFFSET (binfo)));
3541 "offset of empty base %qT may not be ABI-compliant and may"
3542 "change in a future version of GCC",
3543 BINFO_TYPE (binfo));
3546 /* This is an empty base class. We first try to put it at offset
3548 if (layout_conflict_p (binfo,
3549 BINFO_OFFSET (binfo),
3553 /* That didn't work. Now, we move forward from the next
3554 available spot in the class. */
3556 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3559 if (!layout_conflict_p (binfo,
3560 BINFO_OFFSET (binfo),
3563 /* We finally found a spot where there's no overlap. */
3566 /* There's overlap here, too. Bump along to the next spot. */
3567 propagate_binfo_offsets (binfo, alignment);
3571 if (CLASSTYPE_USER_ALIGN (basetype))
3573 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3575 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3576 TYPE_USER_ALIGN (rli->t) = 1;
3582 /* Layout the base given by BINFO in the class indicated by RLI.
3583 *BASE_ALIGN is a running maximum of the alignments of
3584 any base class. OFFSETS gives the location of empty base
3585 subobjects. T is the most derived type. Return nonzero if the new
3586 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3587 *NEXT_FIELD, unless BINFO is for an empty base class.
3589 Returns the location at which the next field should be inserted. */
3592 build_base_field (record_layout_info rli, tree binfo,
3593 splay_tree offsets, tree *next_field)
3596 tree basetype = BINFO_TYPE (binfo);
3598 if (!COMPLETE_TYPE_P (basetype))
3599 /* This error is now reported in xref_tag, thus giving better
3600 location information. */
3603 /* Place the base class. */
3604 if (!is_empty_class (basetype))
3608 /* The containing class is non-empty because it has a non-empty
3610 CLASSTYPE_EMPTY_P (t) = 0;
3612 /* Create the FIELD_DECL. */
3613 decl = build_decl (FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3614 DECL_ARTIFICIAL (decl) = 1;
3615 DECL_IGNORED_P (decl) = 1;
3616 DECL_FIELD_CONTEXT (decl) = t;
3617 if (CLASSTYPE_AS_BASE (basetype))
3619 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3620 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3621 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3622 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3623 DECL_MODE (decl) = TYPE_MODE (basetype);
3624 DECL_FIELD_IS_BASE (decl) = 1;
3626 /* Try to place the field. It may take more than one try if we
3627 have a hard time placing the field without putting two
3628 objects of the same type at the same address. */
3629 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3630 /* Add the new FIELD_DECL to the list of fields for T. */
3631 TREE_CHAIN (decl) = *next_field;
3633 next_field = &TREE_CHAIN (decl);
3641 /* On some platforms (ARM), even empty classes will not be
3643 eoc = round_up (rli_size_unit_so_far (rli),
3644 CLASSTYPE_ALIGN_UNIT (basetype));
3645 atend = layout_empty_base (rli, binfo, eoc, offsets);
3646 /* A nearly-empty class "has no proper base class that is empty,
3647 not morally virtual, and at an offset other than zero." */
3648 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3651 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3652 /* The check above (used in G++ 3.2) is insufficient because
3653 an empty class placed at offset zero might itself have an
3654 empty base at a nonzero offset. */
3655 else if (walk_subobject_offsets (basetype,
3656 empty_base_at_nonzero_offset_p,
3659 /*max_offset=*/NULL_TREE,
3662 if (abi_version_at_least (2))
3663 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3666 "class %qT will be considered nearly empty in a "
3667 "future version of GCC", t);
3671 /* We do not create a FIELD_DECL for empty base classes because
3672 it might overlap some other field. We want to be able to
3673 create CONSTRUCTORs for the class by iterating over the
3674 FIELD_DECLs, and the back end does not handle overlapping
3677 /* An empty virtual base causes a class to be non-empty
3678 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3679 here because that was already done when the virtual table
3680 pointer was created. */
3683 /* Record the offsets of BINFO and its base subobjects. */
3684 record_subobject_offsets (binfo,
3685 BINFO_OFFSET (binfo),
3687 /*is_data_member=*/false);
3692 /* Layout all of the non-virtual base classes. Record empty
3693 subobjects in OFFSETS. T is the most derived type. Return nonzero
3694 if the type cannot be nearly empty. The fields created
3695 corresponding to the base classes will be inserted at
3699 build_base_fields (record_layout_info rli,
3700 splay_tree offsets, tree *next_field)
3702 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3705 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3708 /* The primary base class is always allocated first. */
3709 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3710 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3711 offsets, next_field);
3713 /* Now allocate the rest of the bases. */
3714 for (i = 0; i < n_baseclasses; ++i)
3718 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3720 /* The primary base was already allocated above, so we don't
3721 need to allocate it again here. */
3722 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3725 /* Virtual bases are added at the end (a primary virtual base
3726 will have already been added). */
3727 if (BINFO_VIRTUAL_P (base_binfo))
3730 next_field = build_base_field (rli, base_binfo,
3731 offsets, next_field);
3735 /* Go through the TYPE_METHODS of T issuing any appropriate
3736 diagnostics, figuring out which methods override which other
3737 methods, and so forth. */
3740 check_methods (tree t)
3744 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3746 check_for_override (x, t);
3747 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3748 error ("initializer specified for non-virtual method %q+D", x);
3749 /* The name of the field is the original field name
3750 Save this in auxiliary field for later overloading. */
3751 if (DECL_VINDEX (x))
3753 TYPE_POLYMORPHIC_P (t) = 1;
3754 if (DECL_PURE_VIRTUAL_P (x))
3755 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3757 /* All user-declared destructors are non-trivial. */
3758 if (DECL_DESTRUCTOR_P (x))
3759 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3763 /* FN is a constructor or destructor. Clone the declaration to create
3764 a specialized in-charge or not-in-charge version, as indicated by
3768 build_clone (tree fn, tree name)
3773 /* Copy the function. */
3774 clone = copy_decl (fn);
3775 /* Remember where this function came from. */
3776 DECL_CLONED_FUNCTION (clone) = fn;
3777 DECL_ABSTRACT_ORIGIN (clone) = fn;
3778 /* Reset the function name. */
3779 DECL_NAME (clone) = name;
3780 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3781 /* There's no pending inline data for this function. */
3782 DECL_PENDING_INLINE_INFO (clone) = NULL;
3783 DECL_PENDING_INLINE_P (clone) = 0;
3784 /* And it hasn't yet been deferred. */
3785 DECL_DEFERRED_FN (clone) = 0;
3787 /* The base-class destructor is not virtual. */
3788 if (name == base_dtor_identifier)
3790 DECL_VIRTUAL_P (clone) = 0;
3791 if (TREE_CODE (clone) != TEMPLATE_DECL)
3792 DECL_VINDEX (clone) = NULL_TREE;
3795 /* If there was an in-charge parameter, drop it from the function
3797 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3803 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3804 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3805 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3806 /* Skip the `this' parameter. */
3807 parmtypes = TREE_CHAIN (parmtypes);
3808 /* Skip the in-charge parameter. */
3809 parmtypes = TREE_CHAIN (parmtypes);
3810 /* And the VTT parm, in a complete [cd]tor. */
3811 if (DECL_HAS_VTT_PARM_P (fn)
3812 && ! DECL_NEEDS_VTT_PARM_P (clone))
3813 parmtypes = TREE_CHAIN (parmtypes);
3814 /* If this is subobject constructor or destructor, add the vtt
3817 = build_method_type_directly (basetype,
3818 TREE_TYPE (TREE_TYPE (clone)),
3821 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3824 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3825 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3828 /* Copy the function parameters. But, DECL_ARGUMENTS on a TEMPLATE_DECL
3829 aren't function parameters; those are the template parameters. */
3830 if (TREE_CODE (clone) != TEMPLATE_DECL)
3832 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3833 /* Remove the in-charge parameter. */
3834 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3836 TREE_CHAIN (DECL_ARGUMENTS (clone))
3837 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3838 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3840 /* And the VTT parm, in a complete [cd]tor. */
3841 if (DECL_HAS_VTT_PARM_P (fn))
3843 if (DECL_NEEDS_VTT_PARM_P (clone))
3844 DECL_HAS_VTT_PARM_P (clone) = 1;
3847 TREE_CHAIN (DECL_ARGUMENTS (clone))
3848 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3849 DECL_HAS_VTT_PARM_P (clone) = 0;
3853 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3855 DECL_CONTEXT (parms) = clone;
3856 cxx_dup_lang_specific_decl (parms);
3860 /* Create the RTL for this function. */
3861 SET_DECL_RTL (clone, NULL_RTX);
3862 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3864 /* Make it easy to find the CLONE given the FN. */
3865 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3866 TREE_CHAIN (fn) = clone;
3868 /* If this is a template, handle the DECL_TEMPLATE_RESULT as well. */
3869 if (TREE_CODE (clone) == TEMPLATE_DECL)
3873 DECL_TEMPLATE_RESULT (clone)
3874 = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3875 result = DECL_TEMPLATE_RESULT (clone);
3876 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3877 DECL_TI_TEMPLATE (result) = clone;
3880 note_decl_for_pch (clone);
3885 /* Produce declarations for all appropriate clones of FN. If
3886 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
3887 CLASTYPE_METHOD_VEC as well. */
3890 clone_function_decl (tree fn, int update_method_vec_p)
3894 /* Avoid inappropriate cloning. */
3896 && DECL_CLONED_FUNCTION (TREE_CHAIN (fn)))
3899 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
3901 /* For each constructor, we need two variants: an in-charge version
3902 and a not-in-charge version. */
3903 clone = build_clone (fn, complete_ctor_identifier);
3904 if (update_method_vec_p)
3905 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3906 clone = build_clone (fn, base_ctor_identifier);
3907 if (update_method_vec_p)
3908 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3912 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
3914 /* For each destructor, we need three variants: an in-charge
3915 version, a not-in-charge version, and an in-charge deleting
3916 version. We clone the deleting version first because that
3917 means it will go second on the TYPE_METHODS list -- and that
3918 corresponds to the correct layout order in the virtual
3921 For a non-virtual destructor, we do not build a deleting
3923 if (DECL_VIRTUAL_P (fn))
3925 clone = build_clone (fn, deleting_dtor_identifier);
3926 if (update_method_vec_p)
3927 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3929 clone = build_clone (fn, complete_dtor_identifier);
3930 if (update_method_vec_p)
3931 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3932 clone = build_clone (fn, base_dtor_identifier);
3933 if (update_method_vec_p)
3934 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3937 /* Note that this is an abstract function that is never emitted. */
3938 DECL_ABSTRACT (fn) = 1;
3941 /* DECL is an in charge constructor, which is being defined. This will
3942 have had an in class declaration, from whence clones were
3943 declared. An out-of-class definition can specify additional default
3944 arguments. As it is the clones that are involved in overload
3945 resolution, we must propagate the information from the DECL to its
3949 adjust_clone_args (tree decl)
3953 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION (clone);
3954 clone = TREE_CHAIN (clone))
3956 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
3957 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
3958 tree decl_parms, clone_parms;
3960 clone_parms = orig_clone_parms;
3962 /* Skip the 'this' parameter. */
3963 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
3964 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3966 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
3967 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3968 if (DECL_HAS_VTT_PARM_P (decl))
3969 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3971 clone_parms = orig_clone_parms;
3972 if (DECL_HAS_VTT_PARM_P (clone))
3973 clone_parms = TREE_CHAIN (clone_parms);
3975 for (decl_parms = orig_decl_parms; decl_parms;
3976 decl_parms = TREE_CHAIN (decl_parms),
3977 clone_parms = TREE_CHAIN (clone_parms))
3979 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
3980 TREE_TYPE (clone_parms)));
3982 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
3984 /* A default parameter has been added. Adjust the
3985 clone's parameters. */
3986 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3987 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3990 clone_parms = orig_decl_parms;
3992 if (DECL_HAS_VTT_PARM_P (clone))
3994 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
3995 TREE_VALUE (orig_clone_parms),
3997 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
3999 type = build_method_type_directly (basetype,
4000 TREE_TYPE (TREE_TYPE (clone)),
4003 type = build_exception_variant (type, exceptions);
4004 TREE_TYPE (clone) = type;
4006 clone_parms = NULL_TREE;
4010 gcc_assert (!clone_parms);
4014 /* For each of the constructors and destructors in T, create an
4015 in-charge and not-in-charge variant. */
4018 clone_constructors_and_destructors (tree t)
4022 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4024 if (!CLASSTYPE_METHOD_VEC (t))
4027 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4028 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4029 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4030 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4033 /* Remove all zero-width bit-fields from T. */
4036 remove_zero_width_bit_fields (tree t)
4040 fieldsp = &TYPE_FIELDS (t);
4043 if (TREE_CODE (*fieldsp) == FIELD_DECL
4044 && DECL_C_BIT_FIELD (*fieldsp)
4045 && DECL_INITIAL (*fieldsp))
4046 *fieldsp = TREE_CHAIN (*fieldsp);
4048 fieldsp = &TREE_CHAIN (*fieldsp);
4052 /* Returns TRUE iff we need a cookie when dynamically allocating an
4053 array whose elements have the indicated class TYPE. */
4056 type_requires_array_cookie (tree type)
4059 bool has_two_argument_delete_p = false;
4061 gcc_assert (CLASS_TYPE_P (type));
4063 /* If there's a non-trivial destructor, we need a cookie. In order
4064 to iterate through the array calling the destructor for each
4065 element, we'll have to know how many elements there are. */
4066 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4069 /* If the usual deallocation function is a two-argument whose second
4070 argument is of type `size_t', then we have to pass the size of
4071 the array to the deallocation function, so we will need to store
4073 fns = lookup_fnfields (TYPE_BINFO (type),
4074 ansi_opname (VEC_DELETE_EXPR),
4076 /* If there are no `operator []' members, or the lookup is
4077 ambiguous, then we don't need a cookie. */
4078 if (!fns || fns == error_mark_node)
4080 /* Loop through all of the functions. */
4081 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4086 /* Select the current function. */
4087 fn = OVL_CURRENT (fns);
4088 /* See if this function is a one-argument delete function. If
4089 it is, then it will be the usual deallocation function. */
4090 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4091 if (second_parm == void_list_node)
4093 /* Otherwise, if we have a two-argument function and the second
4094 argument is `size_t', it will be the usual deallocation
4095 function -- unless there is one-argument function, too. */
4096 if (TREE_CHAIN (second_parm) == void_list_node
4097 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4098 has_two_argument_delete_p = true;
4101 return has_two_argument_delete_p;
4104 /* Check the validity of the bases and members declared in T. Add any
4105 implicitly-generated functions (like copy-constructors and
4106 assignment operators). Compute various flag bits (like
4107 CLASSTYPE_NON_POD_T) for T. This routine works purely at the C++
4108 level: i.e., independently of the ABI in use. */
4111 check_bases_and_members (tree t)
4113 /* Nonzero if the implicitly generated copy constructor should take
4114 a non-const reference argument. */
4115 int cant_have_const_ctor;
4116 /* Nonzero if the implicitly generated assignment operator
4117 should take a non-const reference argument. */
4118 int no_const_asn_ref;
4121 /* By default, we use const reference arguments and generate default
4123 cant_have_const_ctor = 0;
4124 no_const_asn_ref = 0;
4126 /* Check all the base-classes. */
4127 check_bases (t, &cant_have_const_ctor,
4130 /* Check all the method declarations. */
4133 /* Check all the data member declarations. We cannot call
4134 check_field_decls until we have called check_bases check_methods,
4135 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4136 being set appropriately. */
4137 check_field_decls (t, &access_decls,
4138 &cant_have_const_ctor,
4141 /* A nearly-empty class has to be vptr-containing; a nearly empty
4142 class contains just a vptr. */
4143 if (!TYPE_CONTAINS_VPTR_P (t))
4144 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4146 /* Do some bookkeeping that will guide the generation of implicitly
4147 declared member functions. */
4148 TYPE_HAS_COMPLEX_INIT_REF (t)
4149 |= (TYPE_HAS_INIT_REF (t) || TYPE_CONTAINS_VPTR_P (t));
4150 TYPE_NEEDS_CONSTRUCTING (t)
4151 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_CONTAINS_VPTR_P (t));
4152 CLASSTYPE_NON_AGGREGATE (t)
4153 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_POLYMORPHIC_P (t));
4154 CLASSTYPE_NON_POD_P (t)
4155 |= (CLASSTYPE_NON_AGGREGATE (t)
4156 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
4157 || TYPE_HAS_ASSIGN_REF (t));
4158 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
4159 |= TYPE_HAS_ASSIGN_REF (t) || TYPE_CONTAINS_VPTR_P (t);
4160 TYPE_HAS_COMPLEX_DFLT (t)
4161 |= (TYPE_HAS_DEFAULT_CONSTRUCTOR (t) || TYPE_CONTAINS_VPTR_P (t));
4163 /* Synthesize any needed methods. */
4164 add_implicitly_declared_members (t,
4165 cant_have_const_ctor,
4168 /* Create the in-charge and not-in-charge variants of constructors
4170 clone_constructors_and_destructors (t);
4172 /* Process the using-declarations. */
4173 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4174 handle_using_decl (TREE_VALUE (access_decls), t);
4176 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4177 finish_struct_methods (t);
4179 /* Figure out whether or not we will need a cookie when dynamically
4180 allocating an array of this type. */
4181 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4182 = type_requires_array_cookie (t);
4185 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4186 accordingly. If a new vfield was created (because T doesn't have a
4187 primary base class), then the newly created field is returned. It
4188 is not added to the TYPE_FIELDS list; it is the caller's
4189 responsibility to do that. Accumulate declared virtual functions
4193 create_vtable_ptr (tree t, tree* virtuals_p)
4197 /* Collect the virtual functions declared in T. */
4198 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4199 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4200 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4202 tree new_virtual = make_node (TREE_LIST);
4204 BV_FN (new_virtual) = fn;
4205 BV_DELTA (new_virtual) = integer_zero_node;
4206 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4208 TREE_CHAIN (new_virtual) = *virtuals_p;
4209 *virtuals_p = new_virtual;
4212 /* If we couldn't find an appropriate base class, create a new field
4213 here. Even if there weren't any new virtual functions, we might need a
4214 new virtual function table if we're supposed to include vptrs in
4215 all classes that need them. */
4216 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4218 /* We build this decl with vtbl_ptr_type_node, which is a
4219 `vtable_entry_type*'. It might seem more precise to use
4220 `vtable_entry_type (*)[N]' where N is the number of virtual
4221 functions. However, that would require the vtable pointer in
4222 base classes to have a different type than the vtable pointer
4223 in derived classes. We could make that happen, but that
4224 still wouldn't solve all the problems. In particular, the
4225 type-based alias analysis code would decide that assignments
4226 to the base class vtable pointer can't alias assignments to
4227 the derived class vtable pointer, since they have different
4228 types. Thus, in a derived class destructor, where the base
4229 class constructor was inlined, we could generate bad code for
4230 setting up the vtable pointer.
4232 Therefore, we use one type for all vtable pointers. We still
4233 use a type-correct type; it's just doesn't indicate the array
4234 bounds. That's better than using `void*' or some such; it's
4235 cleaner, and it let's the alias analysis code know that these
4236 stores cannot alias stores to void*! */
4239 field = build_decl (FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4240 DECL_VIRTUAL_P (field) = 1;
4241 DECL_ARTIFICIAL (field) = 1;
4242 DECL_FIELD_CONTEXT (field) = t;
4243 DECL_FCONTEXT (field) = t;
4245 TYPE_VFIELD (t) = field;
4247 /* This class is non-empty. */
4248 CLASSTYPE_EMPTY_P (t) = 0;
4256 /* Fixup the inline function given by INFO now that the class is
4260 fixup_pending_inline (tree fn)
4262 if (DECL_PENDING_INLINE_INFO (fn))
4264 tree args = DECL_ARGUMENTS (fn);
4267 DECL_CONTEXT (args) = fn;
4268 args = TREE_CHAIN (args);
4273 /* Fixup the inline methods and friends in TYPE now that TYPE is
4277 fixup_inline_methods (tree type)
4279 tree method = TYPE_METHODS (type);
4280 VEC(tree,gc) *friends;
4283 if (method && TREE_CODE (method) == TREE_VEC)
4285 if (TREE_VEC_ELT (method, 1))
4286 method = TREE_VEC_ELT (method, 1);
4287 else if (TREE_VEC_ELT (method, 0))
4288 method = TREE_VEC_ELT (method, 0);
4290 method = TREE_VEC_ELT (method, 2);
4293 /* Do inline member functions. */
4294 for (; method; method = TREE_CHAIN (method))
4295 fixup_pending_inline (method);
4298 for (friends = CLASSTYPE_INLINE_FRIENDS (type), ix = 0;
4299 VEC_iterate (tree, friends, ix, method); ix++)
4300 fixup_pending_inline (method);
4301 CLASSTYPE_INLINE_FRIENDS (type) = NULL;
4304 /* Add OFFSET to all base types of BINFO which is a base in the
4305 hierarchy dominated by T.
4307 OFFSET, which is a type offset, is number of bytes. */
4310 propagate_binfo_offsets (tree binfo, tree offset)
4316 /* Update BINFO's offset. */
4317 BINFO_OFFSET (binfo)
4318 = convert (sizetype,
4319 size_binop (PLUS_EXPR,
4320 convert (ssizetype, BINFO_OFFSET (binfo)),
4323 /* Find the primary base class. */
4324 primary_binfo = get_primary_binfo (binfo);
4326 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4327 propagate_binfo_offsets (primary_binfo, offset);
4329 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4331 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4333 /* Don't do the primary base twice. */
4334 if (base_binfo == primary_binfo)
4337 if (BINFO_VIRTUAL_P (base_binfo))
4340 propagate_binfo_offsets (base_binfo, offset);
4344 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4345 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4346 empty subobjects of T. */
4349 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4353 bool first_vbase = true;
4356 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4359 if (!abi_version_at_least(2))
4361 /* In G++ 3.2, we incorrectly rounded the size before laying out
4362 the virtual bases. */
4363 finish_record_layout (rli, /*free_p=*/false);
4364 #ifdef STRUCTURE_SIZE_BOUNDARY
4365 /* Packed structures don't need to have minimum size. */
4366 if (! TYPE_PACKED (t))
4367 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4369 rli->offset = TYPE_SIZE_UNIT (t);
4370 rli->bitpos = bitsize_zero_node;
4371 rli->record_align = TYPE_ALIGN (t);
4374 /* Find the last field. The artificial fields created for virtual
4375 bases will go after the last extant field to date. */
4376 next_field = &TYPE_FIELDS (t);
4378 next_field = &TREE_CHAIN (*next_field);
4380 /* Go through the virtual bases, allocating space for each virtual
4381 base that is not already a primary base class. These are
4382 allocated in inheritance graph order. */
4383 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4385 if (!BINFO_VIRTUAL_P (vbase))
4388 if (!BINFO_PRIMARY_P (vbase))
4390 tree basetype = TREE_TYPE (vbase);
4392 /* This virtual base is not a primary base of any class in the
4393 hierarchy, so we have to add space for it. */
4394 next_field = build_base_field (rli, vbase,
4395 offsets, next_field);
4397 /* If the first virtual base might have been placed at a
4398 lower address, had we started from CLASSTYPE_SIZE, rather
4399 than TYPE_SIZE, issue a warning. There can be both false
4400 positives and false negatives from this warning in rare
4401 cases; to deal with all the possibilities would probably
4402 require performing both layout algorithms and comparing
4403 the results which is not particularly tractable. */
4407 (size_binop (CEIL_DIV_EXPR,
4408 round_up (CLASSTYPE_SIZE (t),
4409 CLASSTYPE_ALIGN (basetype)),
4411 BINFO_OFFSET (vbase))))
4413 "offset of virtual base %qT is not ABI-compliant and "
4414 "may change in a future version of GCC",
4417 first_vbase = false;
4422 /* Returns the offset of the byte just past the end of the base class
4426 end_of_base (tree binfo)
4430 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
4431 size = TYPE_SIZE_UNIT (char_type_node);
4432 else if (is_empty_class (BINFO_TYPE (binfo)))
4433 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4434 allocate some space for it. It cannot have virtual bases, so
4435 TYPE_SIZE_UNIT is fine. */
4436 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4438 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4440 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4443 /* Returns the offset of the byte just past the end of the base class
4444 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4445 only non-virtual bases are included. */
4448 end_of_class (tree t, int include_virtuals_p)
4450 tree result = size_zero_node;
4451 VEC(tree,gc) *vbases;
4457 for (binfo = TYPE_BINFO (t), i = 0;
4458 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4460 if (!include_virtuals_p
4461 && BINFO_VIRTUAL_P (base_binfo)
4462 && (!BINFO_PRIMARY_P (base_binfo)
4463 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4466 offset = end_of_base (base_binfo);
4467 if (INT_CST_LT_UNSIGNED (result, offset))
4471 /* G++ 3.2 did not check indirect virtual bases. */
4472 if (abi_version_at_least (2) && include_virtuals_p)
4473 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4474 VEC_iterate (tree, vbases, i, base_binfo); i++)
4476 offset = end_of_base (base_binfo);
4477 if (INT_CST_LT_UNSIGNED (result, offset))
4484 /* Warn about bases of T that are inaccessible because they are
4485 ambiguous. For example:
4488 struct T : public S {};
4489 struct U : public S, public T {};
4491 Here, `(S*) new U' is not allowed because there are two `S'
4495 warn_about_ambiguous_bases (tree t)
4498 VEC(tree,gc) *vbases;
4503 /* If there are no repeated bases, nothing can be ambiguous. */
4504 if (!CLASSTYPE_REPEATED_BASE_P (t))
4507 /* Check direct bases. */
4508 for (binfo = TYPE_BINFO (t), i = 0;
4509 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4511 basetype = BINFO_TYPE (base_binfo);
4513 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4514 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4518 /* Check for ambiguous virtual bases. */
4520 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4521 VEC_iterate (tree, vbases, i, binfo); i++)
4523 basetype = BINFO_TYPE (binfo);
4525 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4526 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4531 /* Compare two INTEGER_CSTs K1 and K2. */
4534 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4536 return tree_int_cst_compare ((tree) k1, (tree) k2);
4539 /* Increase the size indicated in RLI to account for empty classes
4540 that are "off the end" of the class. */
4543 include_empty_classes (record_layout_info rli)
4548 /* It might be the case that we grew the class to allocate a
4549 zero-sized base class. That won't be reflected in RLI, yet,
4550 because we are willing to overlay multiple bases at the same
4551 offset. However, now we need to make sure that RLI is big enough
4552 to reflect the entire class. */
4553 eoc = end_of_class (rli->t,
4554 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4555 rli_size = rli_size_unit_so_far (rli);
4556 if (TREE_CODE (rli_size) == INTEGER_CST
4557 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4559 if (!abi_version_at_least (2))
4560 /* In version 1 of the ABI, the size of a class that ends with
4561 a bitfield was not rounded up to a whole multiple of a
4562 byte. Because rli_size_unit_so_far returns only the number
4563 of fully allocated bytes, any extra bits were not included
4565 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4567 /* The size should have been rounded to a whole byte. */
4568 gcc_assert (tree_int_cst_equal
4569 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4571 = size_binop (PLUS_EXPR,
4573 size_binop (MULT_EXPR,
4574 convert (bitsizetype,
4575 size_binop (MINUS_EXPR,
4577 bitsize_int (BITS_PER_UNIT)));
4578 normalize_rli (rli);
4582 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4583 BINFO_OFFSETs for all of the base-classes. Position the vtable
4584 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4587 layout_class_type (tree t, tree *virtuals_p)
4589 tree non_static_data_members;
4592 record_layout_info rli;
4593 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4594 types that appear at that offset. */
4595 splay_tree empty_base_offsets;
4596 /* True if the last field layed out was a bit-field. */
4597 bool last_field_was_bitfield = false;
4598 /* The location at which the next field should be inserted. */
4600 /* T, as a base class. */
4603 /* Keep track of the first non-static data member. */
4604 non_static_data_members = TYPE_FIELDS (t);
4606 /* Start laying out the record. */
4607 rli = start_record_layout (t);
4609 /* Mark all the primary bases in the hierarchy. */
4610 determine_primary_bases (t);
4612 /* Create a pointer to our virtual function table. */
4613 vptr = create_vtable_ptr (t, virtuals_p);
4615 /* The vptr is always the first thing in the class. */
4618 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4619 TYPE_FIELDS (t) = vptr;
4620 next_field = &TREE_CHAIN (vptr);
4621 place_field (rli, vptr);
4624 next_field = &TYPE_FIELDS (t);
4626 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4627 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4629 build_base_fields (rli, empty_base_offsets, next_field);
4631 /* Layout the non-static data members. */
4632 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4637 /* We still pass things that aren't non-static data members to
4638 the back end, in case it wants to do something with them. */
4639 if (TREE_CODE (field) != FIELD_DECL)
4641 place_field (rli, field);
4642 /* If the static data member has incomplete type, keep track
4643 of it so that it can be completed later. (The handling
4644 of pending statics in finish_record_layout is
4645 insufficient; consider:
4648 struct S2 { static S1 s1; };
4650 At this point, finish_record_layout will be called, but
4651 S1 is still incomplete.) */
4652 if (TREE_CODE (field) == VAR_DECL)
4654 maybe_register_incomplete_var (field);
4655 /* The visibility of static data members is determined
4656 at their point of declaration, not their point of
4658 determine_visibility (field);
4663 type = TREE_TYPE (field);
4664 if (type == error_mark_node)
4667 padding = NULL_TREE;
4669 /* If this field is a bit-field whose width is greater than its
4670 type, then there are some special rules for allocating
4672 if (DECL_C_BIT_FIELD (field)
4673 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4675 integer_type_kind itk;
4677 bool was_unnamed_p = false;
4678 /* We must allocate the bits as if suitably aligned for the
4679 longest integer type that fits in this many bits. type
4680 of the field. Then, we are supposed to use the left over
4681 bits as additional padding. */
4682 for (itk = itk_char; itk != itk_none; ++itk)
4683 if (INT_CST_LT (DECL_SIZE (field),
4684 TYPE_SIZE (integer_types[itk])))
4687 /* ITK now indicates a type that is too large for the
4688 field. We have to back up by one to find the largest
4690 integer_type = integer_types[itk - 1];
4692 /* Figure out how much additional padding is required. GCC
4693 3.2 always created a padding field, even if it had zero
4695 if (!abi_version_at_least (2)
4696 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4698 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4699 /* In a union, the padding field must have the full width
4700 of the bit-field; all fields start at offset zero. */
4701 padding = DECL_SIZE (field);
4704 if (TREE_CODE (t) == UNION_TYPE)
4705 warning (OPT_Wabi, "size assigned to %qT may not be "
4706 "ABI-compliant and may change in a future "
4709 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4710 TYPE_SIZE (integer_type));
4713 #ifdef PCC_BITFIELD_TYPE_MATTERS
4714 /* An unnamed bitfield does not normally affect the
4715 alignment of the containing class on a target where
4716 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4717 make any exceptions for unnamed bitfields when the
4718 bitfields are longer than their types. Therefore, we
4719 temporarily give the field a name. */
4720 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4722 was_unnamed_p = true;
4723 DECL_NAME (field) = make_anon_name ();
4726 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4727 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4728 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4729 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4730 empty_base_offsets);
4732 DECL_NAME (field) = NULL_TREE;
4733 /* Now that layout has been performed, set the size of the
4734 field to the size of its declared type; the rest of the
4735 field is effectively invisible. */
4736 DECL_SIZE (field) = TYPE_SIZE (type);
4737 /* We must also reset the DECL_MODE of the field. */
4738 if (abi_version_at_least (2))
4739 DECL_MODE (field) = TYPE_MODE (type);
4741 && DECL_MODE (field) != TYPE_MODE (type))
4742 /* Versions of G++ before G++ 3.4 did not reset the
4745 "the offset of %qD may not be ABI-compliant and may "
4746 "change in a future version of GCC", field);
4749 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4750 empty_base_offsets);
4752 /* Remember the location of any empty classes in FIELD. */
4753 if (abi_version_at_least (2))
4754 record_subobject_offsets (TREE_TYPE (field),
4755 byte_position(field),
4757 /*is_data_member=*/true);
4759 /* If a bit-field does not immediately follow another bit-field,
4760 and yet it starts in the middle of a byte, we have failed to
4761 comply with the ABI. */
4763 && DECL_C_BIT_FIELD (field)
4764 /* The TREE_NO_WARNING flag gets set by Objective-C when
4765 laying out an Objective-C class. The ObjC ABI differs
4766 from the C++ ABI, and so we do not want a warning
4768 && !TREE_NO_WARNING (field)
4769 && !last_field_was_bitfield
4770 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
4771 DECL_FIELD_BIT_OFFSET (field),
4772 bitsize_unit_node)))
4773 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
4774 "change in a future version of GCC", field);
4776 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
4777 offset of the field. */
4779 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
4780 byte_position (field))
4781 && contains_empty_class_p (TREE_TYPE (field)))
4782 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
4783 "classes to be placed at different locations in a "
4784 "future version of GCC", field);
4786 /* The middle end uses the type of expressions to determine the
4787 possible range of expression values. In order to optimize
4788 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
4789 must be made aware of the width of "i", via its type.
4791 Because C++ does not have integer types of arbitrary width,
4792 we must (for the purposes of the front end) convert from the
4793 type assigned here to the declared type of the bitfield
4794 whenever a bitfield expression is used as an rvalue.
4795 Similarly, when assigning a value to a bitfield, the value
4796 must be converted to the type given the bitfield here. */
4797 if (DECL_C_BIT_FIELD (field))
4799 unsigned HOST_WIDE_INT width;
4800 tree ftype = TREE_TYPE (field);
4801 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
4802 if (width != TYPE_PRECISION (ftype))
4805 = c_build_bitfield_integer_type (width,
4806 TYPE_UNSIGNED (ftype));
4808 = cp_build_qualified_type (TREE_TYPE (field),
4809 TYPE_QUALS (ftype));
4813 /* If we needed additional padding after this field, add it
4819 padding_field = build_decl (FIELD_DECL,
4822 DECL_BIT_FIELD (padding_field) = 1;
4823 DECL_SIZE (padding_field) = padding;
4824 DECL_CONTEXT (padding_field) = t;
4825 DECL_ARTIFICIAL (padding_field) = 1;
4826 DECL_IGNORED_P (padding_field) = 1;
4827 layout_nonempty_base_or_field (rli, padding_field,
4829 empty_base_offsets);
4832 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
4835 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
4837 /* Make sure that we are on a byte boundary so that the size of
4838 the class without virtual bases will always be a round number
4840 rli->bitpos = round_up (rli->bitpos, BITS_PER_UNIT);
4841 normalize_rli (rli);
4844 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
4846 if (!abi_version_at_least (2))
4847 include_empty_classes(rli);
4849 /* Delete all zero-width bit-fields from the list of fields. Now
4850 that the type is laid out they are no longer important. */
4851 remove_zero_width_bit_fields (t);
4853 /* Create the version of T used for virtual bases. We do not use
4854 make_aggr_type for this version; this is an artificial type. For
4855 a POD type, we just reuse T. */
4856 if (CLASSTYPE_NON_POD_P (t) || CLASSTYPE_EMPTY_P (t))
4858 base_t = make_node (TREE_CODE (t));
4860 /* Set the size and alignment for the new type. In G++ 3.2, all
4861 empty classes were considered to have size zero when used as
4863 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
4865 TYPE_SIZE (base_t) = bitsize_zero_node;
4866 TYPE_SIZE_UNIT (base_t) = size_zero_node;
4867 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
4869 "layout of classes derived from empty class %qT "
4870 "may change in a future version of GCC",
4877 /* If the ABI version is not at least two, and the last
4878 field was a bit-field, RLI may not be on a byte
4879 boundary. In particular, rli_size_unit_so_far might
4880 indicate the last complete byte, while rli_size_so_far
4881 indicates the total number of bits used. Therefore,
4882 rli_size_so_far, rather than rli_size_unit_so_far, is
4883 used to compute TYPE_SIZE_UNIT. */
4884 eoc = end_of_class (t, /*include_virtuals_p=*/0);
4885 TYPE_SIZE_UNIT (base_t)
4886 = size_binop (MAX_EXPR,
4888 size_binop (CEIL_DIV_EXPR,
4889 rli_size_so_far (rli),
4890 bitsize_int (BITS_PER_UNIT))),
4893 = size_binop (MAX_EXPR,
4894 rli_size_so_far (rli),
4895 size_binop (MULT_EXPR,
4896 convert (bitsizetype, eoc),
4897 bitsize_int (BITS_PER_UNIT)));
4899 TYPE_ALIGN (base_t) = rli->record_align;
4900 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
4902 /* Copy the fields from T. */
4903 next_field = &TYPE_FIELDS (base_t);
4904 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4905 if (TREE_CODE (field) == FIELD_DECL)
4907 *next_field = build_decl (FIELD_DECL,
4910 DECL_CONTEXT (*next_field) = base_t;
4911 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
4912 DECL_FIELD_BIT_OFFSET (*next_field)
4913 = DECL_FIELD_BIT_OFFSET (field);
4914 DECL_SIZE (*next_field) = DECL_SIZE (field);
4915 DECL_MODE (*next_field) = DECL_MODE (field);
4916 next_field = &TREE_CHAIN (*next_field);
4919 /* Record the base version of the type. */
4920 CLASSTYPE_AS_BASE (t) = base_t;
4921 TYPE_CONTEXT (base_t) = t;
4924 CLASSTYPE_AS_BASE (t) = t;
4926 /* Every empty class contains an empty class. */
4927 if (CLASSTYPE_EMPTY_P (t))
4928 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
4930 /* Set the TYPE_DECL for this type to contain the right
4931 value for DECL_OFFSET, so that we can use it as part
4932 of a COMPONENT_REF for multiple inheritance. */
4933 layout_decl (TYPE_MAIN_DECL (t), 0);
4935 /* Now fix up any virtual base class types that we left lying
4936 around. We must get these done before we try to lay out the
4937 virtual function table. As a side-effect, this will remove the
4938 base subobject fields. */
4939 layout_virtual_bases (rli, empty_base_offsets);
4941 /* Make sure that empty classes are reflected in RLI at this
4943 include_empty_classes(rli);
4945 /* Make sure not to create any structures with zero size. */
4946 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
4948 build_decl (FIELD_DECL, NULL_TREE, char_type_node));
4950 /* Let the back end lay out the type. */
4951 finish_record_layout (rli, /*free_p=*/true);
4953 /* Warn about bases that can't be talked about due to ambiguity. */
4954 warn_about_ambiguous_bases (t);
4956 /* Now that we're done with layout, give the base fields the real types. */
4957 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4958 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
4959 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
4962 splay_tree_delete (empty_base_offsets);
4964 if (CLASSTYPE_EMPTY_P (t)
4965 && tree_int_cst_lt (sizeof_biggest_empty_class,
4966 TYPE_SIZE_UNIT (t)))
4967 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
4970 /* Determine the "key method" for the class type indicated by TYPE,
4971 and set CLASSTYPE_KEY_METHOD accordingly. */
4974 determine_key_method (tree type)
4978 if (TYPE_FOR_JAVA (type)
4979 || processing_template_decl
4980 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
4981 || CLASSTYPE_INTERFACE_KNOWN (type))
4984 /* The key method is the first non-pure virtual function that is not
4985 inline at the point of class definition. On some targets the
4986 key function may not be inline; those targets should not call
4987 this function until the end of the translation unit. */
4988 for (method = TYPE_METHODS (type); method != NULL_TREE;
4989 method = TREE_CHAIN (method))
4990 if (DECL_VINDEX (method) != NULL_TREE
4991 && ! DECL_DECLARED_INLINE_P (method)
4992 && ! DECL_PURE_VIRTUAL_P (method))
4994 CLASSTYPE_KEY_METHOD (type) = method;
5001 /* Perform processing required when the definition of T (a class type)
5005 finish_struct_1 (tree t)
5008 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5009 tree virtuals = NULL_TREE;
5012 if (COMPLETE_TYPE_P (t))
5014 gcc_assert (IS_AGGR_TYPE (t));
5015 error ("redefinition of %q#T", t);
5020 /* If this type was previously laid out as a forward reference,
5021 make sure we lay it out again. */
5022 TYPE_SIZE (t) = NULL_TREE;
5023 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5025 fixup_inline_methods (t);
5027 /* Make assumptions about the class; we'll reset the flags if
5029 CLASSTYPE_EMPTY_P (t) = 1;
5030 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5031 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5033 /* Do end-of-class semantic processing: checking the validity of the
5034 bases and members and add implicitly generated methods. */
5035 check_bases_and_members (t);
5037 /* Find the key method. */
5038 if (TYPE_CONTAINS_VPTR_P (t))
5040 /* The Itanium C++ ABI permits the key method to be chosen when
5041 the class is defined -- even though the key method so
5042 selected may later turn out to be an inline function. On
5043 some systems (such as ARM Symbian OS) the key method cannot
5044 be determined until the end of the translation unit. On such
5045 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5046 will cause the class to be added to KEYED_CLASSES. Then, in
5047 finish_file we will determine the key method. */
5048 if (targetm.cxx.key_method_may_be_inline ())
5049 determine_key_method (t);
5051 /* If a polymorphic class has no key method, we may emit the vtable
5052 in every translation unit where the class definition appears. */
5053 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5054 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5057 /* Layout the class itself. */
5058 layout_class_type (t, &virtuals);
5059 if (CLASSTYPE_AS_BASE (t) != t)
5060 /* We use the base type for trivial assignments, and hence it
5062 compute_record_mode (CLASSTYPE_AS_BASE (t));
5064 virtuals = modify_all_vtables (t, nreverse (virtuals));
5066 /* If necessary, create the primary vtable for this class. */
5067 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5069 /* We must enter these virtuals into the table. */
5070 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5071 build_primary_vtable (NULL_TREE, t);
5072 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5073 /* Here we know enough to change the type of our virtual
5074 function table, but we will wait until later this function. */
5075 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5078 if (TYPE_CONTAINS_VPTR_P (t))
5083 if (BINFO_VTABLE (TYPE_BINFO (t)))
5084 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5085 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5086 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5088 /* Add entries for virtual functions introduced by this class. */
5089 BINFO_VIRTUALS (TYPE_BINFO (t))
5090 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5092 /* Set DECL_VINDEX for all functions declared in this class. */
5093 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5095 fn = TREE_CHAIN (fn),
5096 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5097 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5099 tree fndecl = BV_FN (fn);
5101 if (DECL_THUNK_P (fndecl))
5102 /* A thunk. We should never be calling this entry directly
5103 from this vtable -- we'd use the entry for the non
5104 thunk base function. */
5105 DECL_VINDEX (fndecl) = NULL_TREE;
5106 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5107 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5111 finish_struct_bits (t);
5113 /* Complete the rtl for any static member objects of the type we're
5115 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5116 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5117 && TREE_TYPE (x) != error_mark_node
5118 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5119 DECL_MODE (x) = TYPE_MODE (t);
5121 /* Done with FIELDS...now decide whether to sort these for
5122 faster lookups later.
5124 We use a small number because most searches fail (succeeding
5125 ultimately as the search bores through the inheritance
5126 hierarchy), and we want this failure to occur quickly. */
5128 n_fields = count_fields (TYPE_FIELDS (t));
5131 struct sorted_fields_type *field_vec = GGC_NEWVAR
5132 (struct sorted_fields_type,
5133 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5134 field_vec->len = n_fields;
5135 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5136 qsort (field_vec->elts, n_fields, sizeof (tree),
5138 if (! DECL_LANG_SPECIFIC (TYPE_MAIN_DECL (t)))
5139 retrofit_lang_decl (TYPE_MAIN_DECL (t));
5140 DECL_SORTED_FIELDS (TYPE_MAIN_DECL (t)) = field_vec;
5143 /* Complain if one of the field types requires lower visibility. */
5144 constrain_class_visibility (t);
5146 /* Make the rtl for any new vtables we have created, and unmark
5147 the base types we marked. */
5150 /* Build the VTT for T. */
5153 /* This warning does not make sense for Java classes, since they
5154 cannot have destructors. */
5155 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5159 dtor = CLASSTYPE_DESTRUCTORS (t);
5160 if (/* An implicitly declared destructor is always public. And,
5161 if it were virtual, we would have created it by now. */
5163 || (!DECL_VINDEX (dtor)
5164 && (/* public non-virtual */
5165 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5166 || (/* non-public non-virtual with friends */
5167 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5168 && (CLASSTYPE_FRIEND_CLASSES (t)
5169 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5170 warning (OPT_Wnon_virtual_dtor,
5171 "%q#T has virtual functions and accessible"
5172 " non-virtual destructor", t);
5177 if (warn_overloaded_virtual)
5180 /* Class layout, assignment of virtual table slots, etc., is now
5181 complete. Give the back end a chance to tweak the visibility of
5182 the class or perform any other required target modifications. */
5183 targetm.cxx.adjust_class_at_definition (t);
5185 maybe_suppress_debug_info (t);
5187 dump_class_hierarchy (t);
5189 /* Finish debugging output for this type. */
5190 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5193 /* When T was built up, the member declarations were added in reverse
5194 order. Rearrange them to declaration order. */
5197 unreverse_member_declarations (tree t)
5203 /* The following lists are all in reverse order. Put them in
5204 declaration order now. */
5205 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5206 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5208 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5209 reverse order, so we can't just use nreverse. */
5211 for (x = TYPE_FIELDS (t);
5212 x && TREE_CODE (x) != TYPE_DECL;
5215 next = TREE_CHAIN (x);
5216 TREE_CHAIN (x) = prev;
5221 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5223 TYPE_FIELDS (t) = prev;
5228 finish_struct (tree t, tree attributes)
5230 location_t saved_loc = input_location;
5232 /* Now that we've got all the field declarations, reverse everything
5234 unreverse_member_declarations (t);
5236 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5238 /* Nadger the current location so that diagnostics point to the start of
5239 the struct, not the end. */
5240 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5242 if (processing_template_decl)
5246 finish_struct_methods (t);
5247 TYPE_SIZE (t) = bitsize_zero_node;
5248 TYPE_SIZE_UNIT (t) = size_zero_node;
5250 /* We need to emit an error message if this type was used as a parameter
5251 and it is an abstract type, even if it is a template. We construct
5252 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5253 account and we call complete_vars with this type, which will check
5254 the PARM_DECLS. Note that while the type is being defined,
5255 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5256 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5257 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5258 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5259 if (DECL_PURE_VIRTUAL_P (x))
5260 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5264 finish_struct_1 (t);
5266 input_location = saved_loc;
5268 TYPE_BEING_DEFINED (t) = 0;
5270 if (current_class_type)
5273 error ("trying to finish struct, but kicked out due to previous parse errors");
5275 if (processing_template_decl && at_function_scope_p ())
5276 add_stmt (build_min (TAG_DEFN, t));
5281 /* Return the dynamic type of INSTANCE, if known.
5282 Used to determine whether the virtual function table is needed
5285 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5286 of our knowledge of its type. *NONNULL should be initialized
5287 before this function is called. */
5290 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5292 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5294 switch (TREE_CODE (instance))
5297 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5300 return RECUR (TREE_OPERAND (instance, 0));
5303 /* This is a call to a constructor, hence it's never zero. */
5304 if (TREE_HAS_CONSTRUCTOR (instance))
5308 return TREE_TYPE (instance);
5313 /* This is a call to a constructor, hence it's never zero. */
5314 if (TREE_HAS_CONSTRUCTOR (instance))
5318 return TREE_TYPE (instance);
5320 return RECUR (TREE_OPERAND (instance, 0));
5322 case POINTER_PLUS_EXPR:
5325 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5326 return RECUR (TREE_OPERAND (instance, 0));
5327 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5328 /* Propagate nonnull. */
5329 return RECUR (TREE_OPERAND (instance, 0));
5335 return RECUR (TREE_OPERAND (instance, 0));
5338 instance = TREE_OPERAND (instance, 0);
5341 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5342 with a real object -- given &p->f, p can still be null. */
5343 tree t = get_base_address (instance);
5344 /* ??? Probably should check DECL_WEAK here. */
5345 if (t && DECL_P (t))
5348 return RECUR (instance);
5351 /* If this component is really a base class reference, then the field
5352 itself isn't definitive. */
5353 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5354 return RECUR (TREE_OPERAND (instance, 0));
5355 return RECUR (TREE_OPERAND (instance, 1));
5359 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5360 && IS_AGGR_TYPE (TREE_TYPE (TREE_TYPE (instance))))
5364 return TREE_TYPE (TREE_TYPE (instance));
5366 /* fall through... */
5370 if (IS_AGGR_TYPE (TREE_TYPE (instance)))
5374 return TREE_TYPE (instance);
5376 else if (instance == current_class_ptr)
5381 /* if we're in a ctor or dtor, we know our type. */
5382 if (DECL_LANG_SPECIFIC (current_function_decl)
5383 && (DECL_CONSTRUCTOR_P (current_function_decl)
5384 || DECL_DESTRUCTOR_P (current_function_decl)))
5388 return TREE_TYPE (TREE_TYPE (instance));
5391 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5393 /* We only need one hash table because it is always left empty. */
5396 ht = htab_create (37,
5401 /* Reference variables should be references to objects. */
5405 /* Enter the INSTANCE in a table to prevent recursion; a
5406 variable's initializer may refer to the variable
5408 if (TREE_CODE (instance) == VAR_DECL
5409 && DECL_INITIAL (instance)
5410 && !htab_find (ht, instance))
5415 slot = htab_find_slot (ht, instance, INSERT);
5417 type = RECUR (DECL_INITIAL (instance));
5418 htab_remove_elt (ht, instance);
5431 /* Return nonzero if the dynamic type of INSTANCE is known, and
5432 equivalent to the static type. We also handle the case where
5433 INSTANCE is really a pointer. Return negative if this is a
5434 ctor/dtor. There the dynamic type is known, but this might not be
5435 the most derived base of the original object, and hence virtual
5436 bases may not be layed out according to this type.
5438 Used to determine whether the virtual function table is needed
5441 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5442 of our knowledge of its type. *NONNULL should be initialized
5443 before this function is called. */
5446 resolves_to_fixed_type_p (tree instance, int* nonnull)
5448 tree t = TREE_TYPE (instance);
5450 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5451 if (fixed == NULL_TREE)
5453 if (POINTER_TYPE_P (t))
5455 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5457 return cdtorp ? -1 : 1;
5462 init_class_processing (void)
5464 current_class_depth = 0;
5465 current_class_stack_size = 10;
5467 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5468 local_classes = VEC_alloc (tree, gc, 8);
5469 sizeof_biggest_empty_class = size_zero_node;
5471 ridpointers[(int) RID_PUBLIC] = access_public_node;
5472 ridpointers[(int) RID_PRIVATE] = access_private_node;
5473 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5476 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5479 restore_class_cache (void)
5483 /* We are re-entering the same class we just left, so we don't
5484 have to search the whole inheritance matrix to find all the
5485 decls to bind again. Instead, we install the cached
5486 class_shadowed list and walk through it binding names. */
5487 push_binding_level (previous_class_level);
5488 class_binding_level = previous_class_level;
5489 /* Restore IDENTIFIER_TYPE_VALUE. */
5490 for (type = class_binding_level->type_shadowed;
5492 type = TREE_CHAIN (type))
5493 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5496 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5497 appropriate for TYPE.
5499 So that we may avoid calls to lookup_name, we cache the _TYPE
5500 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5502 For multiple inheritance, we perform a two-pass depth-first search
5503 of the type lattice. */
5506 pushclass (tree type)
5508 class_stack_node_t csn;
5510 type = TYPE_MAIN_VARIANT (type);
5512 /* Make sure there is enough room for the new entry on the stack. */
5513 if (current_class_depth + 1 >= current_class_stack_size)
5515 current_class_stack_size *= 2;
5517 = XRESIZEVEC (struct class_stack_node, current_class_stack,
5518 current_class_stack_size);
5521 /* Insert a new entry on the class stack. */
5522 csn = current_class_stack + current_class_depth;
5523 csn->name = current_class_name;
5524 csn->type = current_class_type;
5525 csn->access = current_access_specifier;
5526 csn->names_used = 0;
5528 current_class_depth++;
5530 /* Now set up the new type. */
5531 current_class_name = TYPE_NAME (type);
5532 if (TREE_CODE (current_class_name) == TYPE_DECL)
5533 current_class_name = DECL_NAME (current_class_name);
5534 current_class_type = type;
5536 /* By default, things in classes are private, while things in
5537 structures or unions are public. */
5538 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5539 ? access_private_node
5540 : access_public_node);
5542 if (previous_class_level
5543 && type != previous_class_level->this_entity
5544 && current_class_depth == 1)
5546 /* Forcibly remove any old class remnants. */
5547 invalidate_class_lookup_cache ();
5550 if (!previous_class_level
5551 || type != previous_class_level->this_entity
5552 || current_class_depth > 1)
5555 restore_class_cache ();
5558 /* When we exit a toplevel class scope, we save its binding level so
5559 that we can restore it quickly. Here, we've entered some other
5560 class, so we must invalidate our cache. */
5563 invalidate_class_lookup_cache (void)
5565 previous_class_level = NULL;
5568 /* Get out of the current class scope. If we were in a class scope
5569 previously, that is the one popped to. */
5576 current_class_depth--;
5577 current_class_name = current_class_stack[current_class_depth].name;
5578 current_class_type = current_class_stack[current_class_depth].type;
5579 current_access_specifier = current_class_stack[current_class_depth].access;
5580 if (current_class_stack[current_class_depth].names_used)
5581 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5584 /* Mark the top of the class stack as hidden. */
5587 push_class_stack (void)
5589 if (current_class_depth)
5590 ++current_class_stack[current_class_depth - 1].hidden;
5593 /* Mark the top of the class stack as un-hidden. */
5596 pop_class_stack (void)
5598 if (current_class_depth)
5599 --current_class_stack[current_class_depth - 1].hidden;
5602 /* Returns 1 if the class type currently being defined is either T or
5603 a nested type of T. */
5606 currently_open_class (tree t)
5610 /* We start looking from 1 because entry 0 is from global scope,
5612 for (i = current_class_depth; i > 0; --i)
5615 if (i == current_class_depth)
5616 c = current_class_type;
5619 if (current_class_stack[i].hidden)
5621 c = current_class_stack[i].type;
5625 if (same_type_p (c, t))
5631 /* If either current_class_type or one of its enclosing classes are derived
5632 from T, return the appropriate type. Used to determine how we found
5633 something via unqualified lookup. */
5636 currently_open_derived_class (tree t)
5640 /* The bases of a dependent type are unknown. */
5641 if (dependent_type_p (t))
5644 if (!current_class_type)
5647 if (DERIVED_FROM_P (t, current_class_type))
5648 return current_class_type;
5650 for (i = current_class_depth - 1; i > 0; --i)
5652 if (current_class_stack[i].hidden)
5654 if (DERIVED_FROM_P (t, current_class_stack[i].type))
5655 return current_class_stack[i].type;
5661 /* When entering a class scope, all enclosing class scopes' names with
5662 static meaning (static variables, static functions, types and
5663 enumerators) have to be visible. This recursive function calls
5664 pushclass for all enclosing class contexts until global or a local
5665 scope is reached. TYPE is the enclosed class. */
5668 push_nested_class (tree type)
5670 /* A namespace might be passed in error cases, like A::B:C. */
5671 if (type == NULL_TREE
5672 || !CLASS_TYPE_P (type))
5675 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
5680 /* Undoes a push_nested_class call. */
5683 pop_nested_class (void)
5685 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5688 if (context && CLASS_TYPE_P (context))
5689 pop_nested_class ();
5692 /* Returns the number of extern "LANG" blocks we are nested within. */
5695 current_lang_depth (void)
5697 return VEC_length (tree, current_lang_base);
5700 /* Set global variables CURRENT_LANG_NAME to appropriate value
5701 so that behavior of name-mangling machinery is correct. */
5704 push_lang_context (tree name)
5706 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
5708 if (name == lang_name_cplusplus)
5710 current_lang_name = name;
5712 else if (name == lang_name_java)
5714 current_lang_name = name;
5715 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5716 (See record_builtin_java_type in decl.c.) However, that causes
5717 incorrect debug entries if these types are actually used.
5718 So we re-enable debug output after extern "Java". */
5719 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
5720 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
5721 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
5722 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
5723 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
5724 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
5725 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
5726 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
5728 else if (name == lang_name_c)
5730 current_lang_name = name;
5733 error ("language string %<\"%E\"%> not recognized", name);
5736 /* Get out of the current language scope. */
5739 pop_lang_context (void)
5741 current_lang_name = VEC_pop (tree, current_lang_base);
5744 /* Type instantiation routines. */
5746 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
5747 matches the TARGET_TYPE. If there is no satisfactory match, return
5748 error_mark_node, and issue an error & warning messages under
5749 control of FLAGS. Permit pointers to member function if FLAGS
5750 permits. If TEMPLATE_ONLY, the name of the overloaded function was
5751 a template-id, and EXPLICIT_TARGS are the explicitly provided
5752 template arguments. If OVERLOAD is for one or more member
5753 functions, then ACCESS_PATH is the base path used to reference
5754 those member functions. */
5757 resolve_address_of_overloaded_function (tree target_type,
5759 tsubst_flags_t flags,
5761 tree explicit_targs,
5764 /* Here's what the standard says:
5768 If the name is a function template, template argument deduction
5769 is done, and if the argument deduction succeeds, the deduced
5770 arguments are used to generate a single template function, which
5771 is added to the set of overloaded functions considered.
5773 Non-member functions and static member functions match targets of
5774 type "pointer-to-function" or "reference-to-function." Nonstatic
5775 member functions match targets of type "pointer-to-member
5776 function;" the function type of the pointer to member is used to
5777 select the member function from the set of overloaded member
5778 functions. If a nonstatic member function is selected, the
5779 reference to the overloaded function name is required to have the
5780 form of a pointer to member as described in 5.3.1.
5782 If more than one function is selected, any template functions in
5783 the set are eliminated if the set also contains a non-template
5784 function, and any given template function is eliminated if the
5785 set contains a second template function that is more specialized
5786 than the first according to the partial ordering rules 14.5.5.2.
5787 After such eliminations, if any, there shall remain exactly one
5788 selected function. */
5791 int is_reference = 0;
5792 /* We store the matches in a TREE_LIST rooted here. The functions
5793 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
5794 interoperability with most_specialized_instantiation. */
5795 tree matches = NULL_TREE;
5798 /* By the time we get here, we should be seeing only real
5799 pointer-to-member types, not the internal POINTER_TYPE to
5800 METHOD_TYPE representation. */
5801 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
5802 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
5804 gcc_assert (is_overloaded_fn (overload));
5806 /* Check that the TARGET_TYPE is reasonable. */
5807 if (TYPE_PTRFN_P (target_type))
5809 else if (TYPE_PTRMEMFUNC_P (target_type))
5810 /* This is OK, too. */
5812 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
5814 /* This is OK, too. This comes from a conversion to reference
5816 target_type = build_reference_type (target_type);
5821 if (flags & tf_error)
5822 error ("cannot resolve overloaded function %qD based on"
5823 " conversion to type %qT",
5824 DECL_NAME (OVL_FUNCTION (overload)), target_type);
5825 return error_mark_node;
5828 /* If we can find a non-template function that matches, we can just
5829 use it. There's no point in generating template instantiations
5830 if we're just going to throw them out anyhow. But, of course, we
5831 can only do this when we don't *need* a template function. */
5836 for (fns = overload; fns; fns = OVL_NEXT (fns))
5838 tree fn = OVL_CURRENT (fns);
5841 if (TREE_CODE (fn) == TEMPLATE_DECL)
5842 /* We're not looking for templates just yet. */
5845 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5847 /* We're looking for a non-static member, and this isn't
5848 one, or vice versa. */
5851 /* Ignore functions which haven't been explicitly
5853 if (DECL_ANTICIPATED (fn))
5856 /* See if there's a match. */
5857 fntype = TREE_TYPE (fn);
5859 fntype = build_ptrmemfunc_type (build_pointer_type (fntype));
5860 else if (!is_reference)
5861 fntype = build_pointer_type (fntype);
5863 if (can_convert_arg (target_type, fntype, fn, LOOKUP_NORMAL))
5864 matches = tree_cons (fn, NULL_TREE, matches);
5868 /* Now, if we've already got a match (or matches), there's no need
5869 to proceed to the template functions. But, if we don't have a
5870 match we need to look at them, too. */
5873 tree target_fn_type;
5874 tree target_arg_types;
5875 tree target_ret_type;
5880 = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (target_type));
5882 target_fn_type = TREE_TYPE (target_type);
5883 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
5884 target_ret_type = TREE_TYPE (target_fn_type);
5886 /* Never do unification on the 'this' parameter. */
5887 if (TREE_CODE (target_fn_type) == METHOD_TYPE)
5888 target_arg_types = TREE_CHAIN (target_arg_types);
5890 for (fns = overload; fns; fns = OVL_NEXT (fns))
5892 tree fn = OVL_CURRENT (fns);
5894 tree instantiation_type;
5897 if (TREE_CODE (fn) != TEMPLATE_DECL)
5898 /* We're only looking for templates. */
5901 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5903 /* We're not looking for a non-static member, and this is
5904 one, or vice versa. */
5907 /* Try to do argument deduction. */
5908 targs = make_tree_vec (DECL_NTPARMS (fn));
5909 if (fn_type_unification (fn, explicit_targs, targs,
5910 target_arg_types, target_ret_type,
5911 DEDUCE_EXACT, LOOKUP_NORMAL))
5912 /* Argument deduction failed. */
5915 /* Instantiate the template. */
5916 instantiation = instantiate_template (fn, targs, flags);
5917 if (instantiation == error_mark_node)
5918 /* Instantiation failed. */
5921 /* See if there's a match. */
5922 instantiation_type = TREE_TYPE (instantiation);
5924 instantiation_type =
5925 build_ptrmemfunc_type (build_pointer_type (instantiation_type));
5926 else if (!is_reference)
5927 instantiation_type = build_pointer_type (instantiation_type);
5928 if (can_convert_arg (target_type, instantiation_type, instantiation,
5930 matches = tree_cons (instantiation, fn, matches);
5933 /* Now, remove all but the most specialized of the matches. */
5936 tree match = most_specialized_instantiation (matches);
5938 if (match != error_mark_node)
5939 matches = tree_cons (TREE_PURPOSE (match),
5945 /* Now we should have exactly one function in MATCHES. */
5946 if (matches == NULL_TREE)
5948 /* There were *no* matches. */
5949 if (flags & tf_error)
5951 error ("no matches converting function %qD to type %q#T",
5952 DECL_NAME (OVL_FUNCTION (overload)),
5955 /* print_candidates expects a chain with the functions in
5956 TREE_VALUE slots, so we cons one up here (we're losing anyway,
5957 so why be clever?). */
5958 for (; overload; overload = OVL_NEXT (overload))
5959 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
5962 print_candidates (matches);
5964 return error_mark_node;
5966 else if (TREE_CHAIN (matches))
5968 /* There were too many matches. */
5970 if (flags & tf_error)
5974 error ("converting overloaded function %qD to type %q#T is ambiguous",
5975 DECL_NAME (OVL_FUNCTION (overload)),
5978 /* Since print_candidates expects the functions in the
5979 TREE_VALUE slot, we flip them here. */
5980 for (match = matches; match; match = TREE_CHAIN (match))
5981 TREE_VALUE (match) = TREE_PURPOSE (match);
5983 print_candidates (matches);
5986 return error_mark_node;
5989 /* Good, exactly one match. Now, convert it to the correct type. */
5990 fn = TREE_PURPOSE (matches);
5992 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
5993 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
5995 static int explained;
5997 if (!(flags & tf_error))
5998 return error_mark_node;
6000 pedwarn ("assuming pointer to member %qD", fn);
6003 pedwarn ("(a pointer to member can only be formed with %<&%E%>)", fn);
6008 /* If we're doing overload resolution purely for the purpose of
6009 determining conversion sequences, we should not consider the
6010 function used. If this conversion sequence is selected, the
6011 function will be marked as used at this point. */
6012 if (!(flags & tf_conv))
6015 /* We could not check access when this expression was originally
6016 created since we did not know at that time to which function
6017 the expression referred. */
6018 if (DECL_FUNCTION_MEMBER_P (fn))
6020 gcc_assert (access_path);
6021 perform_or_defer_access_check (access_path, fn, fn);
6025 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6026 return build_unary_op (ADDR_EXPR, fn, 0);
6029 /* The target must be a REFERENCE_TYPE. Above, build_unary_op
6030 will mark the function as addressed, but here we must do it
6032 cxx_mark_addressable (fn);
6038 /* This function will instantiate the type of the expression given in
6039 RHS to match the type of LHSTYPE. If errors exist, then return
6040 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6041 we complain on errors. If we are not complaining, never modify rhs,
6042 as overload resolution wants to try many possible instantiations, in
6043 the hope that at least one will work.
6045 For non-recursive calls, LHSTYPE should be a function, pointer to
6046 function, or a pointer to member function. */
6049 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6051 tsubst_flags_t flags_in = flags;
6052 tree access_path = NULL_TREE;
6054 flags &= ~tf_ptrmem_ok;
6056 if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
6058 if (flags & tf_error)
6059 error ("not enough type information");
6060 return error_mark_node;
6063 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6065 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6067 if (flag_ms_extensions
6068 && TYPE_PTRMEMFUNC_P (lhstype)
6069 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6070 /* Microsoft allows `A::f' to be resolved to a
6071 pointer-to-member. */
6075 if (flags & tf_error)
6076 error ("argument of type %qT does not match %qT",
6077 TREE_TYPE (rhs), lhstype);
6078 return error_mark_node;
6082 if (TREE_CODE (rhs) == BASELINK)
6084 access_path = BASELINK_ACCESS_BINFO (rhs);
6085 rhs = BASELINK_FUNCTIONS (rhs);
6088 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6089 deduce any type information. */
6090 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6092 if (flags & tf_error)
6093 error ("not enough type information");
6094 return error_mark_node;
6097 /* There only a few kinds of expressions that may have a type
6098 dependent on overload resolution. */
6099 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6100 || TREE_CODE (rhs) == COMPONENT_REF
6101 || TREE_CODE (rhs) == COMPOUND_EXPR
6102 || really_overloaded_fn (rhs));
6104 /* We don't overwrite rhs if it is an overloaded function.
6105 Copying it would destroy the tree link. */
6106 if (TREE_CODE (rhs) != OVERLOAD)
6107 rhs = copy_node (rhs);
6109 /* This should really only be used when attempting to distinguish
6110 what sort of a pointer to function we have. For now, any
6111 arithmetic operation which is not supported on pointers
6112 is rejected as an error. */
6114 switch (TREE_CODE (rhs))
6118 tree member = TREE_OPERAND (rhs, 1);
6120 member = instantiate_type (lhstype, member, flags);
6121 if (member != error_mark_node
6122 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6123 /* Do not lose object's side effects. */
6124 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6125 TREE_OPERAND (rhs, 0), member);
6130 rhs = TREE_OPERAND (rhs, 1);
6131 if (BASELINK_P (rhs))
6132 return instantiate_type (lhstype, rhs, flags_in);
6134 /* This can happen if we are forming a pointer-to-member for a
6136 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6140 case TEMPLATE_ID_EXPR:
6142 tree fns = TREE_OPERAND (rhs, 0);
6143 tree args = TREE_OPERAND (rhs, 1);
6146 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6147 /*template_only=*/true,
6154 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6155 /*template_only=*/false,
6156 /*explicit_targs=*/NULL_TREE,
6160 TREE_OPERAND (rhs, 0)
6161 = instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6162 if (TREE_OPERAND (rhs, 0) == error_mark_node)
6163 return error_mark_node;
6164 TREE_OPERAND (rhs, 1)
6165 = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags);
6166 if (TREE_OPERAND (rhs, 1) == error_mark_node)
6167 return error_mark_node;
6169 TREE_TYPE (rhs) = lhstype;
6174 if (PTRMEM_OK_P (rhs))
6175 flags |= tf_ptrmem_ok;
6177 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6181 return error_mark_node;
6186 return error_mark_node;
6189 /* Return the name of the virtual function pointer field
6190 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6191 this may have to look back through base types to find the
6192 ultimate field name. (For single inheritance, these could
6193 all be the same name. Who knows for multiple inheritance). */
6196 get_vfield_name (tree type)
6198 tree binfo, base_binfo;
6201 for (binfo = TYPE_BINFO (type);
6202 BINFO_N_BASE_BINFOS (binfo);
6205 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6207 if (BINFO_VIRTUAL_P (base_binfo)
6208 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6212 type = BINFO_TYPE (binfo);
6213 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6214 + TYPE_NAME_LENGTH (type) + 2);
6215 sprintf (buf, VFIELD_NAME_FORMAT,
6216 IDENTIFIER_POINTER (constructor_name (type)));
6217 return get_identifier (buf);
6221 print_class_statistics (void)
6223 #ifdef GATHER_STATISTICS
6224 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6225 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6228 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6229 n_vtables, n_vtable_searches);
6230 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6231 n_vtable_entries, n_vtable_elems);
6236 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6237 according to [class]:
6238 The class-name is also inserted
6239 into the scope of the class itself. For purposes of access checking,
6240 the inserted class name is treated as if it were a public member name. */
6243 build_self_reference (void)
6245 tree name = constructor_name (current_class_type);
6246 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6249 DECL_NONLOCAL (value) = 1;
6250 DECL_CONTEXT (value) = current_class_type;
6251 DECL_ARTIFICIAL (value) = 1;
6252 SET_DECL_SELF_REFERENCE_P (value);
6254 if (processing_template_decl)
6255 value = push_template_decl (value);
6257 saved_cas = current_access_specifier;
6258 current_access_specifier = access_public_node;
6259 finish_member_declaration (value);
6260 current_access_specifier = saved_cas;
6263 /* Returns 1 if TYPE contains only padding bytes. */
6266 is_empty_class (tree type)
6268 if (type == error_mark_node)
6271 if (! IS_AGGR_TYPE (type))
6274 /* In G++ 3.2, whether or not a class was empty was determined by
6275 looking at its size. */
6276 if (abi_version_at_least (2))
6277 return CLASSTYPE_EMPTY_P (type);
6279 return integer_zerop (CLASSTYPE_SIZE (type));
6282 /* Returns true if TYPE contains an empty class. */
6285 contains_empty_class_p (tree type)
6287 if (is_empty_class (type))
6289 if (CLASS_TYPE_P (type))
6296 for (binfo = TYPE_BINFO (type), i = 0;
6297 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6298 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6300 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6301 if (TREE_CODE (field) == FIELD_DECL
6302 && !DECL_ARTIFICIAL (field)
6303 && is_empty_class (TREE_TYPE (field)))
6306 else if (TREE_CODE (type) == ARRAY_TYPE)
6307 return contains_empty_class_p (TREE_TYPE (type));
6311 /* Note that NAME was looked up while the current class was being
6312 defined and that the result of that lookup was DECL. */
6315 maybe_note_name_used_in_class (tree name, tree decl)
6317 splay_tree names_used;
6319 /* If we're not defining a class, there's nothing to do. */
6320 if (!(innermost_scope_kind() == sk_class
6321 && TYPE_BEING_DEFINED (current_class_type)))
6324 /* If there's already a binding for this NAME, then we don't have
6325 anything to worry about. */
6326 if (lookup_member (current_class_type, name,
6327 /*protect=*/0, /*want_type=*/false))
6330 if (!current_class_stack[current_class_depth - 1].names_used)
6331 current_class_stack[current_class_depth - 1].names_used
6332 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6333 names_used = current_class_stack[current_class_depth - 1].names_used;
6335 splay_tree_insert (names_used,
6336 (splay_tree_key) name,
6337 (splay_tree_value) decl);
6340 /* Note that NAME was declared (as DECL) in the current class. Check
6341 to see that the declaration is valid. */
6344 note_name_declared_in_class (tree name, tree decl)
6346 splay_tree names_used;
6349 /* Look to see if we ever used this name. */
6351 = current_class_stack[current_class_depth - 1].names_used;
6355 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6358 /* [basic.scope.class]
6360 A name N used in a class S shall refer to the same declaration
6361 in its context and when re-evaluated in the completed scope of
6363 pedwarn ("declaration of %q#D", decl);
6364 pedwarn ("changes meaning of %qD from %q+#D",
6365 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6369 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6370 Secondary vtables are merged with primary vtables; this function
6371 will return the VAR_DECL for the primary vtable. */
6374 get_vtbl_decl_for_binfo (tree binfo)
6378 decl = BINFO_VTABLE (binfo);
6379 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
6381 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6382 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6385 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6390 /* Returns the binfo for the primary base of BINFO. If the resulting
6391 BINFO is a virtual base, and it is inherited elsewhere in the
6392 hierarchy, then the returned binfo might not be the primary base of
6393 BINFO in the complete object. Check BINFO_PRIMARY_P or
6394 BINFO_LOST_PRIMARY_P to be sure. */
6397 get_primary_binfo (tree binfo)
6401 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6405 return copied_binfo (primary_base, binfo);
6408 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6411 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6414 fprintf (stream, "%*s", indent, "");
6418 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6419 INDENT should be zero when called from the top level; it is
6420 incremented recursively. IGO indicates the next expected BINFO in
6421 inheritance graph ordering. */
6424 dump_class_hierarchy_r (FILE *stream,
6434 indented = maybe_indent_hierarchy (stream, indent, 0);
6435 fprintf (stream, "%s (0x%lx) ",
6436 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6437 (unsigned long) binfo);
6440 fprintf (stream, "alternative-path\n");
6443 igo = TREE_CHAIN (binfo);
6445 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6446 tree_low_cst (BINFO_OFFSET (binfo), 0));
6447 if (is_empty_class (BINFO_TYPE (binfo)))
6448 fprintf (stream, " empty");
6449 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6450 fprintf (stream, " nearly-empty");
6451 if (BINFO_VIRTUAL_P (binfo))
6452 fprintf (stream, " virtual");
6453 fprintf (stream, "\n");
6456 if (BINFO_PRIMARY_P (binfo))
6458 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6459 fprintf (stream, " primary-for %s (0x%lx)",
6460 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6461 TFF_PLAIN_IDENTIFIER),
6462 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6464 if (BINFO_LOST_PRIMARY_P (binfo))
6466 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6467 fprintf (stream, " lost-primary");
6470 fprintf (stream, "\n");
6472 if (!(flags & TDF_SLIM))
6476 if (BINFO_SUBVTT_INDEX (binfo))
6478 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6479 fprintf (stream, " subvttidx=%s",
6480 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6481 TFF_PLAIN_IDENTIFIER));
6483 if (BINFO_VPTR_INDEX (binfo))
6485 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6486 fprintf (stream, " vptridx=%s",
6487 expr_as_string (BINFO_VPTR_INDEX (binfo),
6488 TFF_PLAIN_IDENTIFIER));
6490 if (BINFO_VPTR_FIELD (binfo))
6492 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6493 fprintf (stream, " vbaseoffset=%s",
6494 expr_as_string (BINFO_VPTR_FIELD (binfo),
6495 TFF_PLAIN_IDENTIFIER));
6497 if (BINFO_VTABLE (binfo))
6499 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6500 fprintf (stream, " vptr=%s",
6501 expr_as_string (BINFO_VTABLE (binfo),
6502 TFF_PLAIN_IDENTIFIER));
6506 fprintf (stream, "\n");
6509 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6510 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6515 /* Dump the BINFO hierarchy for T. */
6518 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6520 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6521 fprintf (stream, " size=%lu align=%lu\n",
6522 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6523 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6524 fprintf (stream, " base size=%lu base align=%lu\n",
6525 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6527 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6529 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6530 fprintf (stream, "\n");
6533 /* Debug interface to hierarchy dumping. */
6536 debug_class (tree t)
6538 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6542 dump_class_hierarchy (tree t)
6545 FILE *stream = dump_begin (TDI_class, &flags);
6549 dump_class_hierarchy_1 (stream, flags, t);
6550 dump_end (TDI_class, stream);
6555 dump_array (FILE * stream, tree decl)
6558 unsigned HOST_WIDE_INT ix;
6560 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6562 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6564 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6565 fprintf (stream, " %s entries",
6566 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6567 TFF_PLAIN_IDENTIFIER));
6568 fprintf (stream, "\n");
6570 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
6572 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
6573 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
6577 dump_vtable (tree t, tree binfo, tree vtable)
6580 FILE *stream = dump_begin (TDI_class, &flags);
6585 if (!(flags & TDF_SLIM))
6587 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6589 fprintf (stream, "%s for %s",
6590 ctor_vtbl_p ? "Construction vtable" : "Vtable",
6591 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6594 if (!BINFO_VIRTUAL_P (binfo))
6595 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6596 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6598 fprintf (stream, "\n");
6599 dump_array (stream, vtable);
6600 fprintf (stream, "\n");
6603 dump_end (TDI_class, stream);
6607 dump_vtt (tree t, tree vtt)
6610 FILE *stream = dump_begin (TDI_class, &flags);
6615 if (!(flags & TDF_SLIM))
6617 fprintf (stream, "VTT for %s\n",
6618 type_as_string (t, TFF_PLAIN_IDENTIFIER));
6619 dump_array (stream, vtt);
6620 fprintf (stream, "\n");
6623 dump_end (TDI_class, stream);
6626 /* Dump a function or thunk and its thunkees. */
6629 dump_thunk (FILE *stream, int indent, tree thunk)
6631 static const char spaces[] = " ";
6632 tree name = DECL_NAME (thunk);
6635 fprintf (stream, "%.*s%p %s %s", indent, spaces,
6637 !DECL_THUNK_P (thunk) ? "function"
6638 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6639 name ? IDENTIFIER_POINTER (name) : "<unset>");
6640 if (DECL_THUNK_P (thunk))
6642 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6643 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6645 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6646 if (!virtual_adjust)
6648 else if (DECL_THIS_THUNK_P (thunk))
6649 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
6650 tree_low_cst (virtual_adjust, 0));
6652 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6653 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6654 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6655 if (THUNK_ALIAS (thunk))
6656 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6658 fprintf (stream, "\n");
6659 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6660 dump_thunk (stream, indent + 2, thunks);
6663 /* Dump the thunks for FN. */
6666 debug_thunks (tree fn)
6668 dump_thunk (stderr, 0, fn);
6671 /* Virtual function table initialization. */
6673 /* Create all the necessary vtables for T and its base classes. */
6676 finish_vtbls (tree t)
6681 /* We lay out the primary and secondary vtables in one contiguous
6682 vtable. The primary vtable is first, followed by the non-virtual
6683 secondary vtables in inheritance graph order. */
6684 list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6685 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6686 TYPE_BINFO (t), t, list);
6688 /* Then come the virtual bases, also in inheritance graph order. */
6689 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6691 if (!BINFO_VIRTUAL_P (vbase))
6693 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6696 if (BINFO_VTABLE (TYPE_BINFO (t)))
6697 initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
6700 /* Initialize the vtable for BINFO with the INITS. */
6703 initialize_vtable (tree binfo, tree inits)
6707 layout_vtable_decl (binfo, list_length (inits));
6708 decl = get_vtbl_decl_for_binfo (binfo);
6709 initialize_artificial_var (decl, inits);
6710 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
6713 /* Build the VTT (virtual table table) for T.
6714 A class requires a VTT if it has virtual bases.
6717 1 - primary virtual pointer for complete object T
6718 2 - secondary VTTs for each direct non-virtual base of T which requires a
6720 3 - secondary virtual pointers for each direct or indirect base of T which
6721 has virtual bases or is reachable via a virtual path from T.
6722 4 - secondary VTTs for each direct or indirect virtual base of T.
6724 Secondary VTTs look like complete object VTTs without part 4. */
6734 /* Build up the initializers for the VTT. */
6736 index = size_zero_node;
6737 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
6739 /* If we didn't need a VTT, we're done. */
6743 /* Figure out the type of the VTT. */
6744 type = build_index_type (size_int (list_length (inits) - 1));
6745 type = build_cplus_array_type (const_ptr_type_node, type);
6747 /* Now, build the VTT object itself. */
6748 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
6749 initialize_artificial_var (vtt, inits);
6750 /* Add the VTT to the vtables list. */
6751 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
6752 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
6757 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
6758 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
6759 and CHAIN the vtable pointer for this binfo after construction is
6760 complete. VALUE can also be another BINFO, in which case we recurse. */
6763 binfo_ctor_vtable (tree binfo)
6769 vt = BINFO_VTABLE (binfo);
6770 if (TREE_CODE (vt) == TREE_LIST)
6771 vt = TREE_VALUE (vt);
6772 if (TREE_CODE (vt) == TREE_BINFO)
6781 /* Data for secondary VTT initialization. */
6782 typedef struct secondary_vptr_vtt_init_data_s
6784 /* Is this the primary VTT? */
6787 /* Current index into the VTT. */
6790 /* TREE_LIST of initializers built up. */
6793 /* The type being constructed by this secondary VTT. */
6794 tree type_being_constructed;
6795 } secondary_vptr_vtt_init_data;
6797 /* Recursively build the VTT-initializer for BINFO (which is in the
6798 hierarchy dominated by T). INITS points to the end of the initializer
6799 list to date. INDEX is the VTT index where the next element will be
6800 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
6801 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
6802 for virtual bases of T. When it is not so, we build the constructor
6803 vtables for the BINFO-in-T variant. */
6806 build_vtt_inits (tree binfo, tree t, tree *inits, tree *index)
6811 tree secondary_vptrs;
6812 secondary_vptr_vtt_init_data data;
6813 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
6815 /* We only need VTTs for subobjects with virtual bases. */
6816 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
6819 /* We need to use a construction vtable if this is not the primary
6823 build_ctor_vtbl_group (binfo, t);
6825 /* Record the offset in the VTT where this sub-VTT can be found. */
6826 BINFO_SUBVTT_INDEX (binfo) = *index;
6829 /* Add the address of the primary vtable for the complete object. */
6830 init = binfo_ctor_vtable (binfo);
6831 *inits = build_tree_list (NULL_TREE, init);
6832 inits = &TREE_CHAIN (*inits);
6835 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6836 BINFO_VPTR_INDEX (binfo) = *index;
6838 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
6840 /* Recursively add the secondary VTTs for non-virtual bases. */
6841 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
6842 if (!BINFO_VIRTUAL_P (b))
6843 inits = build_vtt_inits (b, t, inits, index);
6845 /* Add secondary virtual pointers for all subobjects of BINFO with
6846 either virtual bases or reachable along a virtual path, except
6847 subobjects that are non-virtual primary bases. */
6848 data.top_level_p = top_level_p;
6849 data.index = *index;
6851 data.type_being_constructed = BINFO_TYPE (binfo);
6853 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
6855 *index = data.index;
6857 /* The secondary vptrs come back in reverse order. After we reverse
6858 them, and add the INITS, the last init will be the first element
6860 secondary_vptrs = data.inits;
6861 if (secondary_vptrs)
6863 *inits = nreverse (secondary_vptrs);
6864 inits = &TREE_CHAIN (secondary_vptrs);
6865 gcc_assert (*inits == NULL_TREE);
6869 /* Add the secondary VTTs for virtual bases in inheritance graph
6871 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
6873 if (!BINFO_VIRTUAL_P (b))
6876 inits = build_vtt_inits (b, t, inits, index);
6879 /* Remove the ctor vtables we created. */
6880 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
6885 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
6886 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
6889 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
6891 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
6893 /* We don't care about bases that don't have vtables. */
6894 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
6895 return dfs_skip_bases;
6897 /* We're only interested in proper subobjects of the type being
6899 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
6902 /* We're only interested in bases with virtual bases or reachable
6903 via a virtual path from the type being constructed. */
6904 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
6905 || binfo_via_virtual (binfo, data->type_being_constructed)))
6906 return dfs_skip_bases;
6908 /* We're not interested in non-virtual primary bases. */
6909 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
6912 /* Record the index where this secondary vptr can be found. */
6913 if (data->top_level_p)
6915 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6916 BINFO_VPTR_INDEX (binfo) = data->index;
6918 if (BINFO_VIRTUAL_P (binfo))
6920 /* It's a primary virtual base, and this is not a
6921 construction vtable. Find the base this is primary of in
6922 the inheritance graph, and use that base's vtable
6924 while (BINFO_PRIMARY_P (binfo))
6925 binfo = BINFO_INHERITANCE_CHAIN (binfo);
6929 /* Add the initializer for the secondary vptr itself. */
6930 data->inits = tree_cons (NULL_TREE, binfo_ctor_vtable (binfo), data->inits);
6932 /* Advance the vtt index. */
6933 data->index = size_binop (PLUS_EXPR, data->index,
6934 TYPE_SIZE_UNIT (ptr_type_node));
6939 /* Called from build_vtt_inits via dfs_walk. After building
6940 constructor vtables and generating the sub-vtt from them, we need
6941 to restore the BINFO_VTABLES that were scribbled on. DATA is the
6942 binfo of the base whose sub vtt was generated. */
6945 dfs_fixup_binfo_vtbls (tree binfo, void* data)
6947 tree vtable = BINFO_VTABLE (binfo);
6949 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
6950 /* If this class has no vtable, none of its bases do. */
6951 return dfs_skip_bases;
6954 /* This might be a primary base, so have no vtable in this
6958 /* If we scribbled the construction vtable vptr into BINFO, clear it
6960 if (TREE_CODE (vtable) == TREE_LIST
6961 && (TREE_PURPOSE (vtable) == (tree) data))
6962 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
6967 /* Build the construction vtable group for BINFO which is in the
6968 hierarchy dominated by T. */
6971 build_ctor_vtbl_group (tree binfo, tree t)
6980 /* See if we've already created this construction vtable group. */
6981 id = mangle_ctor_vtbl_for_type (t, binfo);
6982 if (IDENTIFIER_GLOBAL_VALUE (id))
6985 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
6986 /* Build a version of VTBL (with the wrong type) for use in
6987 constructing the addresses of secondary vtables in the
6988 construction vtable group. */
6989 vtbl = build_vtable (t, id, ptr_type_node);
6990 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
6991 list = build_tree_list (vtbl, NULL_TREE);
6992 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
6995 /* Add the vtables for each of our virtual bases using the vbase in T
6997 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
6999 vbase = TREE_CHAIN (vbase))
7003 if (!BINFO_VIRTUAL_P (vbase))
7005 b = copied_binfo (vbase, binfo);
7007 accumulate_vtbl_inits (b, vbase, binfo, t, list);
7009 inits = TREE_VALUE (list);
7011 /* Figure out the type of the construction vtable. */
7012 type = build_index_type (size_int (list_length (inits) - 1));
7013 type = build_cplus_array_type (vtable_entry_type, type);
7015 TREE_TYPE (vtbl) = type;
7016 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7017 layout_decl (vtbl, 0);
7019 /* Initialize the construction vtable. */
7020 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7021 initialize_artificial_var (vtbl, inits);
7022 dump_vtable (t, binfo, vtbl);
7025 /* Add the vtbl initializers for BINFO (and its bases other than
7026 non-virtual primaries) to the list of INITS. BINFO is in the
7027 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7028 the constructor the vtbl inits should be accumulated for. (If this
7029 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7030 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7031 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7032 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7033 but are not necessarily the same in terms of layout. */
7036 accumulate_vtbl_inits (tree binfo,
7044 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7046 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7048 /* If it doesn't have a vptr, we don't do anything. */
7049 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7052 /* If we're building a construction vtable, we're not interested in
7053 subobjects that don't require construction vtables. */
7055 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7056 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7059 /* Build the initializers for the BINFO-in-T vtable. */
7061 = chainon (TREE_VALUE (inits),
7062 dfs_accumulate_vtbl_inits (binfo, orig_binfo,
7063 rtti_binfo, t, inits));
7065 /* Walk the BINFO and its bases. We walk in preorder so that as we
7066 initialize each vtable we can figure out at what offset the
7067 secondary vtable lies from the primary vtable. We can't use
7068 dfs_walk here because we need to iterate through bases of BINFO
7069 and RTTI_BINFO simultaneously. */
7070 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7072 /* Skip virtual bases. */
7073 if (BINFO_VIRTUAL_P (base_binfo))
7075 accumulate_vtbl_inits (base_binfo,
7076 BINFO_BASE_BINFO (orig_binfo, i),
7082 /* Called from accumulate_vtbl_inits. Returns the initializers for
7083 the BINFO vtable. */
7086 dfs_accumulate_vtbl_inits (tree binfo,
7092 tree inits = NULL_TREE;
7093 tree vtbl = NULL_TREE;
7094 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7097 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7099 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7100 primary virtual base. If it is not the same primary in
7101 the hierarchy of T, we'll need to generate a ctor vtable
7102 for it, to place at its location in T. If it is the same
7103 primary, we still need a VTT entry for the vtable, but it
7104 should point to the ctor vtable for the base it is a
7105 primary for within the sub-hierarchy of RTTI_BINFO.
7107 There are three possible cases:
7109 1) We are in the same place.
7110 2) We are a primary base within a lost primary virtual base of
7112 3) We are primary to something not a base of RTTI_BINFO. */
7115 tree last = NULL_TREE;
7117 /* First, look through the bases we are primary to for RTTI_BINFO
7118 or a virtual base. */
7120 while (BINFO_PRIMARY_P (b))
7122 b = BINFO_INHERITANCE_CHAIN (b);
7124 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7127 /* If we run out of primary links, keep looking down our
7128 inheritance chain; we might be an indirect primary. */
7129 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7130 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7134 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7135 base B and it is a base of RTTI_BINFO, this is case 2. In
7136 either case, we share our vtable with LAST, i.e. the
7137 derived-most base within B of which we are a primary. */
7139 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7140 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7141 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7142 binfo_ctor_vtable after everything's been set up. */
7145 /* Otherwise, this is case 3 and we get our own. */
7147 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7155 /* Compute the initializer for this vtable. */
7156 inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7159 /* Figure out the position to which the VPTR should point. */
7160 vtbl = TREE_PURPOSE (l);
7161 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7162 index = size_binop (PLUS_EXPR,
7163 size_int (non_fn_entries),
7164 size_int (list_length (TREE_VALUE (l))));
7165 index = size_binop (MULT_EXPR,
7166 TYPE_SIZE_UNIT (vtable_entry_type),
7168 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7172 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7173 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7174 straighten this out. */
7175 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7176 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7179 /* For an ordinary vtable, set BINFO_VTABLE. */
7180 BINFO_VTABLE (binfo) = vtbl;
7185 static GTY(()) tree abort_fndecl_addr;
7187 /* Construct the initializer for BINFO's virtual function table. BINFO
7188 is part of the hierarchy dominated by T. If we're building a
7189 construction vtable, the ORIG_BINFO is the binfo we should use to
7190 find the actual function pointers to put in the vtable - but they
7191 can be overridden on the path to most-derived in the graph that
7192 ORIG_BINFO belongs. Otherwise,
7193 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7194 BINFO that should be indicated by the RTTI information in the
7195 vtable; it will be a base class of T, rather than T itself, if we
7196 are building a construction vtable.
7198 The value returned is a TREE_LIST suitable for wrapping in a
7199 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7200 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7201 number of non-function entries in the vtable.
7203 It might seem that this function should never be called with a
7204 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7205 base is always subsumed by a derived class vtable. However, when
7206 we are building construction vtables, we do build vtables for
7207 primary bases; we need these while the primary base is being
7211 build_vtbl_initializer (tree binfo,
7215 int* non_fn_entries_p)
7222 VEC(tree,gc) *vbases;
7224 /* Initialize VID. */
7225 memset (&vid, 0, sizeof (vid));
7228 vid.rtti_binfo = rtti_binfo;
7229 vid.last_init = &vid.inits;
7230 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7231 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7232 vid.generate_vcall_entries = true;
7233 /* The first vbase or vcall offset is at index -3 in the vtable. */
7234 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7236 /* Add entries to the vtable for RTTI. */
7237 build_rtti_vtbl_entries (binfo, &vid);
7239 /* Create an array for keeping track of the functions we've
7240 processed. When we see multiple functions with the same
7241 signature, we share the vcall offsets. */
7242 vid.fns = VEC_alloc (tree, gc, 32);
7243 /* Add the vcall and vbase offset entries. */
7244 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7246 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7247 build_vbase_offset_vtbl_entries. */
7248 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7249 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7250 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7252 /* If the target requires padding between data entries, add that now. */
7253 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7257 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7262 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7263 add = tree_cons (NULL_TREE,
7264 build1 (NOP_EXPR, vtable_entry_type,
7271 if (non_fn_entries_p)
7272 *non_fn_entries_p = list_length (vid.inits);
7274 /* Go through all the ordinary virtual functions, building up
7276 vfun_inits = NULL_TREE;
7277 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7281 tree fn, fn_original;
7282 tree init = NULL_TREE;
7286 if (DECL_THUNK_P (fn))
7288 if (!DECL_NAME (fn))
7290 if (THUNK_ALIAS (fn))
7292 fn = THUNK_ALIAS (fn);
7295 fn_original = THUNK_TARGET (fn);
7298 /* If the only definition of this function signature along our
7299 primary base chain is from a lost primary, this vtable slot will
7300 never be used, so just zero it out. This is important to avoid
7301 requiring extra thunks which cannot be generated with the function.
7303 We first check this in update_vtable_entry_for_fn, so we handle
7304 restored primary bases properly; we also need to do it here so we
7305 zero out unused slots in ctor vtables, rather than filling themff
7306 with erroneous values (though harmless, apart from relocation
7308 for (b = binfo; ; b = get_primary_binfo (b))
7310 /* We found a defn before a lost primary; go ahead as normal. */
7311 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7314 /* The nearest definition is from a lost primary; clear the
7316 if (BINFO_LOST_PRIMARY_P (b))
7318 init = size_zero_node;
7325 /* Pull the offset for `this', and the function to call, out of
7327 delta = BV_DELTA (v);
7328 vcall_index = BV_VCALL_INDEX (v);
7330 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7331 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7333 /* You can't call an abstract virtual function; it's abstract.
7334 So, we replace these functions with __pure_virtual. */
7335 if (DECL_PURE_VIRTUAL_P (fn_original))
7338 if (abort_fndecl_addr == NULL)
7339 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7340 init = abort_fndecl_addr;
7344 if (!integer_zerop (delta) || vcall_index)
7346 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7347 if (!DECL_NAME (fn))
7350 /* Take the address of the function, considering it to be of an
7351 appropriate generic type. */
7352 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7356 /* And add it to the chain of initializers. */
7357 if (TARGET_VTABLE_USES_DESCRIPTORS)
7360 if (init == size_zero_node)
7361 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7362 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7364 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7366 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7367 TREE_OPERAND (init, 0),
7368 build_int_cst (NULL_TREE, i));
7369 TREE_CONSTANT (fdesc) = 1;
7370 TREE_INVARIANT (fdesc) = 1;
7372 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7376 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7379 /* The initializers for virtual functions were built up in reverse
7380 order; straighten them out now. */
7381 vfun_inits = nreverse (vfun_inits);
7383 /* The negative offset initializers are also in reverse order. */
7384 vid.inits = nreverse (vid.inits);
7386 /* Chain the two together. */
7387 return chainon (vid.inits, vfun_inits);
7390 /* Adds to vid->inits the initializers for the vbase and vcall
7391 offsets in BINFO, which is in the hierarchy dominated by T. */
7394 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7398 /* If this is a derived class, we must first create entries
7399 corresponding to the primary base class. */
7400 b = get_primary_binfo (binfo);
7402 build_vcall_and_vbase_vtbl_entries (b, vid);
7404 /* Add the vbase entries for this base. */
7405 build_vbase_offset_vtbl_entries (binfo, vid);
7406 /* Add the vcall entries for this base. */
7407 build_vcall_offset_vtbl_entries (binfo, vid);
7410 /* Returns the initializers for the vbase offset entries in the vtable
7411 for BINFO (which is part of the class hierarchy dominated by T), in
7412 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7413 where the next vbase offset will go. */
7416 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7420 tree non_primary_binfo;
7422 /* If there are no virtual baseclasses, then there is nothing to
7424 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7429 /* We might be a primary base class. Go up the inheritance hierarchy
7430 until we find the most derived class of which we are a primary base:
7431 it is the offset of that which we need to use. */
7432 non_primary_binfo = binfo;
7433 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7437 /* If we have reached a virtual base, then it must be a primary
7438 base (possibly multi-level) of vid->binfo, or we wouldn't
7439 have called build_vcall_and_vbase_vtbl_entries for it. But it
7440 might be a lost primary, so just skip down to vid->binfo. */
7441 if (BINFO_VIRTUAL_P (non_primary_binfo))
7443 non_primary_binfo = vid->binfo;
7447 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7448 if (get_primary_binfo (b) != non_primary_binfo)
7450 non_primary_binfo = b;
7453 /* Go through the virtual bases, adding the offsets. */
7454 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7456 vbase = TREE_CHAIN (vbase))
7461 if (!BINFO_VIRTUAL_P (vbase))
7464 /* Find the instance of this virtual base in the complete
7466 b = copied_binfo (vbase, binfo);
7468 /* If we've already got an offset for this virtual base, we
7469 don't need another one. */
7470 if (BINFO_VTABLE_PATH_MARKED (b))
7472 BINFO_VTABLE_PATH_MARKED (b) = 1;
7474 /* Figure out where we can find this vbase offset. */
7475 delta = size_binop (MULT_EXPR,
7478 TYPE_SIZE_UNIT (vtable_entry_type)));
7479 if (vid->primary_vtbl_p)
7480 BINFO_VPTR_FIELD (b) = delta;
7482 if (binfo != TYPE_BINFO (t))
7483 /* The vbase offset had better be the same. */
7484 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7486 /* The next vbase will come at a more negative offset. */
7487 vid->index = size_binop (MINUS_EXPR, vid->index,
7488 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7490 /* The initializer is the delta from BINFO to this virtual base.
7491 The vbase offsets go in reverse inheritance-graph order, and
7492 we are walking in inheritance graph order so these end up in
7494 delta = size_diffop (BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7497 = build_tree_list (NULL_TREE,
7498 fold_build1 (NOP_EXPR,
7501 vid->last_init = &TREE_CHAIN (*vid->last_init);
7505 /* Adds the initializers for the vcall offset entries in the vtable
7506 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7510 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7512 /* We only need these entries if this base is a virtual base. We
7513 compute the indices -- but do not add to the vtable -- when
7514 building the main vtable for a class. */
7515 if (binfo == TYPE_BINFO (vid->derived)
7516 || (BINFO_VIRTUAL_P (binfo)
7517 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7518 correspond to VID->DERIVED), we are building a primary
7519 construction virtual table. Since this is a primary
7520 virtual table, we do not need the vcall offsets for
7522 && binfo != vid->rtti_binfo))
7524 /* We need a vcall offset for each of the virtual functions in this
7525 vtable. For example:
7527 class A { virtual void f (); };
7528 class B1 : virtual public A { virtual void f (); };
7529 class B2 : virtual public A { virtual void f (); };
7530 class C: public B1, public B2 { virtual void f (); };
7532 A C object has a primary base of B1, which has a primary base of A. A
7533 C also has a secondary base of B2, which no longer has a primary base
7534 of A. So the B2-in-C construction vtable needs a secondary vtable for
7535 A, which will adjust the A* to a B2* to call f. We have no way of
7536 knowing what (or even whether) this offset will be when we define B2,
7537 so we store this "vcall offset" in the A sub-vtable and look it up in
7538 a "virtual thunk" for B2::f.
7540 We need entries for all the functions in our primary vtable and
7541 in our non-virtual bases' secondary vtables. */
7543 /* If we are just computing the vcall indices -- but do not need
7544 the actual entries -- not that. */
7545 if (!BINFO_VIRTUAL_P (binfo))
7546 vid->generate_vcall_entries = false;
7547 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7548 add_vcall_offset_vtbl_entries_r (binfo, vid);
7552 /* Build vcall offsets, starting with those for BINFO. */
7555 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7561 /* Don't walk into virtual bases -- except, of course, for the
7562 virtual base for which we are building vcall offsets. Any
7563 primary virtual base will have already had its offsets generated
7564 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7565 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7568 /* If BINFO has a primary base, process it first. */
7569 primary_binfo = get_primary_binfo (binfo);
7571 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7573 /* Add BINFO itself to the list. */
7574 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7576 /* Scan the non-primary bases of BINFO. */
7577 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7578 if (base_binfo != primary_binfo)
7579 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7582 /* Called from build_vcall_offset_vtbl_entries_r. */
7585 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7587 /* Make entries for the rest of the virtuals. */
7588 if (abi_version_at_least (2))
7592 /* The ABI requires that the methods be processed in declaration
7593 order. G++ 3.2 used the order in the vtable. */
7594 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7596 orig_fn = TREE_CHAIN (orig_fn))
7597 if (DECL_VINDEX (orig_fn))
7598 add_vcall_offset (orig_fn, binfo, vid);
7602 tree derived_virtuals;
7605 /* If BINFO is a primary base, the most derived class which has
7606 BINFO as a primary base; otherwise, just BINFO. */
7607 tree non_primary_binfo;
7609 /* We might be a primary base class. Go up the inheritance hierarchy
7610 until we find the most derived class of which we are a primary base:
7611 it is the BINFO_VIRTUALS there that we need to consider. */
7612 non_primary_binfo = binfo;
7613 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7617 /* If we have reached a virtual base, then it must be vid->vbase,
7618 because we ignore other virtual bases in
7619 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7620 base (possibly multi-level) of vid->binfo, or we wouldn't
7621 have called build_vcall_and_vbase_vtbl_entries for it. But it
7622 might be a lost primary, so just skip down to vid->binfo. */
7623 if (BINFO_VIRTUAL_P (non_primary_binfo))
7625 gcc_assert (non_primary_binfo == vid->vbase);
7626 non_primary_binfo = vid->binfo;
7630 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7631 if (get_primary_binfo (b) != non_primary_binfo)
7633 non_primary_binfo = b;
7636 if (vid->ctor_vtbl_p)
7637 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7638 where rtti_binfo is the most derived type. */
7640 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7642 for (base_virtuals = BINFO_VIRTUALS (binfo),
7643 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7644 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7646 base_virtuals = TREE_CHAIN (base_virtuals),
7647 derived_virtuals = TREE_CHAIN (derived_virtuals),
7648 orig_virtuals = TREE_CHAIN (orig_virtuals))
7652 /* Find the declaration that originally caused this function to
7653 be present in BINFO_TYPE (binfo). */
7654 orig_fn = BV_FN (orig_virtuals);
7656 /* When processing BINFO, we only want to generate vcall slots for
7657 function slots introduced in BINFO. So don't try to generate
7658 one if the function isn't even defined in BINFO. */
7659 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7662 add_vcall_offset (orig_fn, binfo, vid);
7667 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7670 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7676 /* If there is already an entry for a function with the same
7677 signature as FN, then we do not need a second vcall offset.
7678 Check the list of functions already present in the derived
7680 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7682 if (same_signature_p (derived_entry, orig_fn)
7683 /* We only use one vcall offset for virtual destructors,
7684 even though there are two virtual table entries. */
7685 || (DECL_DESTRUCTOR_P (derived_entry)
7686 && DECL_DESTRUCTOR_P (orig_fn)))
7690 /* If we are building these vcall offsets as part of building
7691 the vtable for the most derived class, remember the vcall
7693 if (vid->binfo == TYPE_BINFO (vid->derived))
7695 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
7696 CLASSTYPE_VCALL_INDICES (vid->derived),
7698 elt->purpose = orig_fn;
7699 elt->value = vid->index;
7702 /* The next vcall offset will be found at a more negative
7704 vid->index = size_binop (MINUS_EXPR, vid->index,
7705 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7707 /* Keep track of this function. */
7708 VEC_safe_push (tree, gc, vid->fns, orig_fn);
7710 if (vid->generate_vcall_entries)
7715 /* Find the overriding function. */
7716 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
7717 if (fn == error_mark_node)
7718 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
7722 base = TREE_VALUE (fn);
7724 /* The vbase we're working on is a primary base of
7725 vid->binfo. But it might be a lost primary, so its
7726 BINFO_OFFSET might be wrong, so we just use the
7727 BINFO_OFFSET from vid->binfo. */
7728 vcall_offset = size_diffop (BINFO_OFFSET (base),
7729 BINFO_OFFSET (vid->binfo));
7730 vcall_offset = fold_build1 (NOP_EXPR, vtable_entry_type,
7733 /* Add the initializer to the vtable. */
7734 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
7735 vid->last_init = &TREE_CHAIN (*vid->last_init);
7739 /* Return vtbl initializers for the RTTI entries corresponding to the
7740 BINFO's vtable. The RTTI entries should indicate the object given
7741 by VID->rtti_binfo. */
7744 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
7753 basetype = BINFO_TYPE (binfo);
7754 t = BINFO_TYPE (vid->rtti_binfo);
7756 /* To find the complete object, we will first convert to our most
7757 primary base, and then add the offset in the vtbl to that value. */
7759 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
7760 && !BINFO_LOST_PRIMARY_P (b))
7764 primary_base = get_primary_binfo (b);
7765 gcc_assert (BINFO_PRIMARY_P (primary_base)
7766 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
7769 offset = size_diffop (BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
7771 /* The second entry is the address of the typeinfo object. */
7773 decl = build_address (get_tinfo_decl (t));
7775 decl = integer_zero_node;
7777 /* Convert the declaration to a type that can be stored in the
7779 init = build_nop (vfunc_ptr_type_node, decl);
7780 *vid->last_init = build_tree_list (NULL_TREE, init);
7781 vid->last_init = &TREE_CHAIN (*vid->last_init);
7783 /* Add the offset-to-top entry. It comes earlier in the vtable than
7784 the typeinfo entry. Convert the offset to look like a
7785 function pointer, so that we can put it in the vtable. */
7786 init = build_nop (vfunc_ptr_type_node, offset);
7787 *vid->last_init = build_tree_list (NULL_TREE, init);
7788 vid->last_init = &TREE_CHAIN (*vid->last_init);
7791 /* Fold a OBJ_TYPE_REF expression to the address of a function.
7792 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
7795 cp_fold_obj_type_ref (tree ref, tree known_type)
7797 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
7798 HOST_WIDE_INT i = 0;
7799 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
7804 i += (TARGET_VTABLE_USES_DESCRIPTORS
7805 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
7811 #ifdef ENABLE_CHECKING
7812 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
7813 DECL_VINDEX (fndecl)));
7816 cgraph_node (fndecl)->local.vtable_method = true;
7818 return build_address (fndecl);
7821 #include "gt-cp-class.h"