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 Free Software Foundation, Inc.
4 Contributed by Michael Tiemann (tiemann@cygnus.com)
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to
20 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
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 void 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 (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 virtual_access = (v_binfo && fixed_type_p <= 0);
296 /* Do we need to check for a null pointer? */
297 if (want_pointer && !nonnull)
299 /* If we know the conversion will not actually change the value
300 of EXPR, then we can avoid testing the expression for NULL.
301 We have to avoid generating a COMPONENT_REF for a base class
302 field, because other parts of the compiler know that such
303 expressions are always non-NULL. */
304 if (!virtual_access && integer_zerop (offset))
305 return build_nop (build_pointer_type (target_type), expr);
306 null_test = error_mark_node;
309 /* Protect against multiple evaluation if necessary. */
310 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
311 expr = save_expr (expr);
313 /* Now that we've saved expr, build the real null test. */
316 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
317 null_test = fold_build2 (NE_EXPR, boolean_type_node,
321 /* If this is a simple base reference, express it as a COMPONENT_REF. */
322 if (code == PLUS_EXPR && !virtual_access
323 /* We don't build base fields for empty bases, and they aren't very
324 interesting to the optimizers anyway. */
327 expr = build_indirect_ref (expr, NULL);
328 expr = build_simple_base_path (expr, binfo);
330 expr = build_address (expr);
331 target_type = TREE_TYPE (expr);
337 /* Going via virtual base V_BINFO. We need the static offset
338 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
339 V_BINFO. That offset is an entry in D_BINFO's vtable. */
342 if (fixed_type_p < 0 && in_base_initializer)
344 /* In a base member initializer, we cannot rely on the
345 vtable being set up. We have to indirect via the
349 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
350 t = build_pointer_type (t);
351 v_offset = convert (t, current_vtt_parm);
352 v_offset = build_indirect_ref (v_offset, NULL);
355 v_offset = build_vfield_ref (build_indirect_ref (expr, NULL),
356 TREE_TYPE (TREE_TYPE (expr)));
358 v_offset = build2 (PLUS_EXPR, TREE_TYPE (v_offset),
359 v_offset, BINFO_VPTR_FIELD (v_binfo));
360 v_offset = build1 (NOP_EXPR,
361 build_pointer_type (ptrdiff_type_node),
363 v_offset = build_indirect_ref (v_offset, NULL);
364 TREE_CONSTANT (v_offset) = 1;
365 TREE_INVARIANT (v_offset) = 1;
367 offset = convert_to_integer (ptrdiff_type_node,
369 BINFO_OFFSET (v_binfo)));
371 if (!integer_zerop (offset))
372 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
374 if (fixed_type_p < 0)
375 /* Negative fixed_type_p means this is a constructor or destructor;
376 virtual base layout is fixed in in-charge [cd]tors, but not in
378 offset = build3 (COND_EXPR, ptrdiff_type_node,
379 build2 (EQ_EXPR, boolean_type_node,
380 current_in_charge_parm, integer_zero_node),
382 convert_to_integer (ptrdiff_type_node,
383 BINFO_OFFSET (binfo)));
388 target_type = cp_build_qualified_type
389 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
390 ptr_target_type = build_pointer_type (target_type);
392 target_type = ptr_target_type;
394 expr = build1 (NOP_EXPR, ptr_target_type, expr);
396 if (!integer_zerop (offset))
397 expr = build2 (code, ptr_target_type, expr, offset);
402 expr = build_indirect_ref (expr, NULL);
406 expr = fold_build3 (COND_EXPR, target_type, null_test, expr,
407 fold_build1 (NOP_EXPR, target_type,
413 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
414 Perform a derived-to-base conversion by recursively building up a
415 sequence of COMPONENT_REFs to the appropriate base fields. */
418 build_simple_base_path (tree expr, tree binfo)
420 tree type = BINFO_TYPE (binfo);
421 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
424 if (d_binfo == NULL_TREE)
428 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
430 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
431 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
432 an lvalue in the frontend; only _DECLs and _REFs are lvalues
434 temp = unary_complex_lvalue (ADDR_EXPR, expr);
436 expr = build_indirect_ref (temp, NULL);
442 expr = build_simple_base_path (expr, d_binfo);
444 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
445 field; field = TREE_CHAIN (field))
446 /* Is this the base field created by build_base_field? */
447 if (TREE_CODE (field) == FIELD_DECL
448 && DECL_FIELD_IS_BASE (field)
449 && TREE_TYPE (field) == type)
451 /* We don't use build_class_member_access_expr here, as that
452 has unnecessary checks, and more importantly results in
453 recursive calls to dfs_walk_once. */
454 int type_quals = cp_type_quals (TREE_TYPE (expr));
456 expr = build3 (COMPONENT_REF,
457 cp_build_qualified_type (type, type_quals),
458 expr, field, NULL_TREE);
459 expr = fold_if_not_in_template (expr);
461 /* Mark the expression const or volatile, as appropriate.
462 Even though we've dealt with the type above, we still have
463 to mark the expression itself. */
464 if (type_quals & TYPE_QUAL_CONST)
465 TREE_READONLY (expr) = 1;
466 if (type_quals & TYPE_QUAL_VOLATILE)
467 TREE_THIS_VOLATILE (expr) = 1;
472 /* Didn't find the base field?!? */
476 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
477 type is a class type or a pointer to a class type. In the former
478 case, TYPE is also a class type; in the latter it is another
479 pointer type. If CHECK_ACCESS is true, an error message is emitted
480 if TYPE is inaccessible. If OBJECT has pointer type, the value is
481 assumed to be non-NULL. */
484 convert_to_base (tree object, tree type, bool check_access, bool nonnull)
489 if (TYPE_PTR_P (TREE_TYPE (object)))
491 object_type = TREE_TYPE (TREE_TYPE (object));
492 type = TREE_TYPE (type);
495 object_type = TREE_TYPE (object);
497 binfo = lookup_base (object_type, type,
498 check_access ? ba_check : ba_unique,
500 if (!binfo || binfo == error_mark_node)
501 return error_mark_node;
503 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
506 /* EXPR is an expression with unqualified class type. BASE is a base
507 binfo of that class type. Returns EXPR, converted to the BASE
508 type. This function assumes that EXPR is the most derived class;
509 therefore virtual bases can be found at their static offsets. */
512 convert_to_base_statically (tree expr, tree base)
516 expr_type = TREE_TYPE (expr);
517 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
521 pointer_type = build_pointer_type (expr_type);
522 expr = build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1);
523 if (!integer_zerop (BINFO_OFFSET (base)))
524 expr = build2 (PLUS_EXPR, pointer_type, expr,
525 build_nop (pointer_type, BINFO_OFFSET (base)));
526 expr = build_nop (build_pointer_type (BINFO_TYPE (base)), expr);
527 expr = build1 (INDIRECT_REF, BINFO_TYPE (base), expr);
535 build_vfield_ref (tree datum, tree type)
537 tree vfield, vcontext;
539 if (datum == error_mark_node)
540 return error_mark_node;
542 /* First, convert to the requested type. */
543 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
544 datum = convert_to_base (datum, type, /*check_access=*/false,
547 /* Second, the requested type may not be the owner of its own vptr.
548 If not, convert to the base class that owns it. We cannot use
549 convert_to_base here, because VCONTEXT may appear more than once
550 in the inheritance hierarchy of TYPE, and thus direct conversion
551 between the types may be ambiguous. Following the path back up
552 one step at a time via primary bases avoids the problem. */
553 vfield = TYPE_VFIELD (type);
554 vcontext = DECL_CONTEXT (vfield);
555 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
557 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
558 type = TREE_TYPE (datum);
561 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
564 /* Given an object INSTANCE, return an expression which yields the
565 vtable element corresponding to INDEX. There are many special
566 cases for INSTANCE which we take care of here, mainly to avoid
567 creating extra tree nodes when we don't have to. */
570 build_vtbl_ref_1 (tree instance, tree idx)
573 tree vtbl = NULL_TREE;
575 /* Try to figure out what a reference refers to, and
576 access its virtual function table directly. */
579 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
581 tree basetype = non_reference (TREE_TYPE (instance));
583 if (fixed_type && !cdtorp)
585 tree binfo = lookup_base (fixed_type, basetype,
586 ba_unique | ba_quiet, NULL);
588 vtbl = unshare_expr (BINFO_VTABLE (binfo));
592 vtbl = build_vfield_ref (instance, basetype);
594 assemble_external (vtbl);
596 aref = build_array_ref (vtbl, idx);
597 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
598 TREE_INVARIANT (aref) = TREE_CONSTANT (aref);
604 build_vtbl_ref (tree instance, tree idx)
606 tree aref = build_vtbl_ref_1 (instance, idx);
611 /* Given a stable object pointer INSTANCE_PTR, return an expression which
612 yields a function pointer corresponding to vtable element INDEX. */
615 build_vfn_ref (tree instance_ptr, tree idx)
619 aref = build_vtbl_ref_1 (build_indirect_ref (instance_ptr, 0), idx);
621 /* When using function descriptors, the address of the
622 vtable entry is treated as a function pointer. */
623 if (TARGET_VTABLE_USES_DESCRIPTORS)
624 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
625 build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1));
627 /* Remember this as a method reference, for later devirtualization. */
628 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
633 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
634 for the given TYPE. */
637 get_vtable_name (tree type)
639 return mangle_vtbl_for_type (type);
642 /* DECL is an entity associated with TYPE, like a virtual table or an
643 implicitly generated constructor. Determine whether or not DECL
644 should have external or internal linkage at the object file
645 level. This routine does not deal with COMDAT linkage and other
646 similar complexities; it simply sets TREE_PUBLIC if it possible for
647 entities in other translation units to contain copies of DECL, in
651 set_linkage_according_to_type (tree type, tree decl)
653 /* If TYPE involves a local class in a function with internal
654 linkage, then DECL should have internal linkage too. Other local
655 classes have no linkage -- but if their containing functions
656 have external linkage, it makes sense for DECL to have external
657 linkage too. That will allow template definitions to be merged,
659 if (no_linkage_check (type, /*relaxed_p=*/true))
661 TREE_PUBLIC (decl) = 0;
662 DECL_INTERFACE_KNOWN (decl) = 1;
665 TREE_PUBLIC (decl) = 1;
668 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
669 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
670 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
673 build_vtable (tree class_type, tree name, tree vtable_type)
677 decl = build_lang_decl (VAR_DECL, name, vtable_type);
678 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
679 now to avoid confusion in mangle_decl. */
680 SET_DECL_ASSEMBLER_NAME (decl, name);
681 DECL_CONTEXT (decl) = class_type;
682 DECL_ARTIFICIAL (decl) = 1;
683 TREE_STATIC (decl) = 1;
684 TREE_READONLY (decl) = 1;
685 DECL_VIRTUAL_P (decl) = 1;
686 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
687 DECL_VTABLE_OR_VTT_P (decl) = 1;
688 /* At one time the vtable info was grabbed 2 words at a time. This
689 fails on sparc unless you have 8-byte alignment. (tiemann) */
690 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
692 set_linkage_according_to_type (class_type, decl);
693 /* The vtable has not been defined -- yet. */
694 DECL_EXTERNAL (decl) = 1;
695 DECL_NOT_REALLY_EXTERN (decl) = 1;
697 /* Mark the VAR_DECL node representing the vtable itself as a
698 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
699 is rather important that such things be ignored because any
700 effort to actually generate DWARF for them will run into
701 trouble when/if we encounter code like:
704 struct S { virtual void member (); };
706 because the artificial declaration of the vtable itself (as
707 manufactured by the g++ front end) will say that the vtable is
708 a static member of `S' but only *after* the debug output for
709 the definition of `S' has already been output. This causes
710 grief because the DWARF entry for the definition of the vtable
711 will try to refer back to an earlier *declaration* of the
712 vtable as a static member of `S' and there won't be one. We
713 might be able to arrange to have the "vtable static member"
714 attached to the member list for `S' before the debug info for
715 `S' get written (which would solve the problem) but that would
716 require more intrusive changes to the g++ front end. */
717 DECL_IGNORED_P (decl) = 1;
722 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
723 or even complete. If this does not exist, create it. If COMPLETE is
724 nonzero, then complete the definition of it -- that will render it
725 impossible to actually build the vtable, but is useful to get at those
726 which are known to exist in the runtime. */
729 get_vtable_decl (tree type, int complete)
733 if (CLASSTYPE_VTABLES (type))
734 return CLASSTYPE_VTABLES (type);
736 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
737 CLASSTYPE_VTABLES (type) = decl;
741 DECL_EXTERNAL (decl) = 1;
742 finish_decl (decl, NULL_TREE, NULL_TREE);
748 /* Build the primary virtual function table for TYPE. If BINFO is
749 non-NULL, build the vtable starting with the initial approximation
750 that it is the same as the one which is the head of the association
751 list. Returns a nonzero value if a new vtable is actually
755 build_primary_vtable (tree binfo, tree type)
760 decl = get_vtable_decl (type, /*complete=*/0);
764 if (BINFO_NEW_VTABLE_MARKED (binfo))
765 /* We have already created a vtable for this base, so there's
766 no need to do it again. */
769 virtuals = copy_list (BINFO_VIRTUALS (binfo));
770 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
771 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
772 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
776 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
777 virtuals = NULL_TREE;
780 #ifdef GATHER_STATISTICS
782 n_vtable_elems += list_length (virtuals);
785 /* Initialize the association list for this type, based
786 on our first approximation. */
787 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
788 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
789 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
793 /* Give BINFO a new virtual function table which is initialized
794 with a skeleton-copy of its original initialization. The only
795 entry that changes is the `delta' entry, so we can really
796 share a lot of structure.
798 FOR_TYPE is the most derived type which caused this table to
801 Returns nonzero if we haven't met BINFO before.
803 The order in which vtables are built (by calling this function) for
804 an object must remain the same, otherwise a binary incompatibility
808 build_secondary_vtable (tree binfo)
810 if (BINFO_NEW_VTABLE_MARKED (binfo))
811 /* We already created a vtable for this base. There's no need to
815 /* Remember that we've created a vtable for this BINFO, so that we
816 don't try to do so again. */
817 SET_BINFO_NEW_VTABLE_MARKED (binfo);
819 /* Make fresh virtual list, so we can smash it later. */
820 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
822 /* Secondary vtables are laid out as part of the same structure as
823 the primary vtable. */
824 BINFO_VTABLE (binfo) = NULL_TREE;
828 /* Create a new vtable for BINFO which is the hierarchy dominated by
829 T. Return nonzero if we actually created a new vtable. */
832 make_new_vtable (tree t, tree binfo)
834 if (binfo == TYPE_BINFO (t))
835 /* In this case, it is *type*'s vtable we are modifying. We start
836 with the approximation that its vtable is that of the
837 immediate base class. */
838 return build_primary_vtable (binfo, t);
840 /* This is our very own copy of `basetype' to play with. Later,
841 we will fill in all the virtual functions that override the
842 virtual functions in these base classes which are not defined
843 by the current type. */
844 return build_secondary_vtable (binfo);
847 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
848 (which is in the hierarchy dominated by T) list FNDECL as its
849 BV_FN. DELTA is the required constant adjustment from the `this'
850 pointer where the vtable entry appears to the `this' required when
851 the function is actually called. */
854 modify_vtable_entry (tree t,
864 if (fndecl != BV_FN (v)
865 || !tree_int_cst_equal (delta, BV_DELTA (v)))
867 /* We need a new vtable for BINFO. */
868 if (make_new_vtable (t, binfo))
870 /* If we really did make a new vtable, we also made a copy
871 of the BINFO_VIRTUALS list. Now, we have to find the
872 corresponding entry in that list. */
873 *virtuals = BINFO_VIRTUALS (binfo);
874 while (BV_FN (*virtuals) != BV_FN (v))
875 *virtuals = TREE_CHAIN (*virtuals);
879 BV_DELTA (v) = delta;
880 BV_VCALL_INDEX (v) = NULL_TREE;
886 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
887 the USING_DECL naming METHOD. Returns true if the method could be
888 added to the method vec. */
891 add_method (tree type, tree method, tree using_decl)
895 bool template_conv_p = false;
897 VEC(tree,gc) *method_vec;
899 bool insert_p = false;
902 if (method == error_mark_node)
905 complete_p = COMPLETE_TYPE_P (type);
906 conv_p = DECL_CONV_FN_P (method);
908 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
909 && DECL_TEMPLATE_CONV_FN_P (method));
911 method_vec = CLASSTYPE_METHOD_VEC (type);
914 /* Make a new method vector. We start with 8 entries. We must
915 allocate at least two (for constructors and destructors), and
916 we're going to end up with an assignment operator at some
918 method_vec = VEC_alloc (tree, gc, 8);
919 /* Create slots for constructors and destructors. */
920 VEC_quick_push (tree, method_vec, NULL_TREE);
921 VEC_quick_push (tree, method_vec, NULL_TREE);
922 CLASSTYPE_METHOD_VEC (type) = method_vec;
925 /* Maintain TYPE_HAS_CONSTRUCTOR, etc. */
926 grok_special_member_properties (method);
928 /* Constructors and destructors go in special slots. */
929 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
930 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
931 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
933 slot = CLASSTYPE_DESTRUCTOR_SLOT;
935 if (TYPE_FOR_JAVA (type))
937 if (!DECL_ARTIFICIAL (method))
938 error ("Java class %qT cannot have a destructor", type);
939 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
940 error ("Java class %qT cannot have an implicit non-trivial "
950 /* See if we already have an entry with this name. */
951 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
952 VEC_iterate (tree, method_vec, slot, m);
958 if (TREE_CODE (m) == TEMPLATE_DECL
959 && DECL_TEMPLATE_CONV_FN_P (m))
963 if (conv_p && !DECL_CONV_FN_P (m))
965 if (DECL_NAME (m) == DECL_NAME (method))
971 && !DECL_CONV_FN_P (m)
972 && DECL_NAME (m) > DECL_NAME (method))
976 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
978 if (processing_template_decl)
979 /* TYPE is a template class. Don't issue any errors now; wait
980 until instantiation time to complain. */
986 /* Check to see if we've already got this method. */
987 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
989 tree fn = OVL_CURRENT (fns);
995 if (TREE_CODE (fn) != TREE_CODE (method))
998 /* [over.load] Member function declarations with the
999 same name and the same parameter types cannot be
1000 overloaded if any of them is a static member
1001 function declaration.
1003 [namespace.udecl] When a using-declaration brings names
1004 from a base class into a derived class scope, member
1005 functions in the derived class override and/or hide member
1006 functions with the same name and parameter types in a base
1007 class (rather than conflicting). */
1008 fn_type = TREE_TYPE (fn);
1009 method_type = TREE_TYPE (method);
1010 parms1 = TYPE_ARG_TYPES (fn_type);
1011 parms2 = TYPE_ARG_TYPES (method_type);
1013 /* Compare the quals on the 'this' parm. Don't compare
1014 the whole types, as used functions are treated as
1015 coming from the using class in overload resolution. */
1016 if (! DECL_STATIC_FUNCTION_P (fn)
1017 && ! DECL_STATIC_FUNCTION_P (method)
1018 && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
1019 != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
1022 /* For templates, the return type and template parameters
1023 must be identical. */
1024 if (TREE_CODE (fn) == TEMPLATE_DECL
1025 && (!same_type_p (TREE_TYPE (fn_type),
1026 TREE_TYPE (method_type))
1027 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1028 DECL_TEMPLATE_PARMS (method))))
1031 if (! DECL_STATIC_FUNCTION_P (fn))
1032 parms1 = TREE_CHAIN (parms1);
1033 if (! DECL_STATIC_FUNCTION_P (method))
1034 parms2 = TREE_CHAIN (parms2);
1036 if (compparms (parms1, parms2)
1037 && (!DECL_CONV_FN_P (fn)
1038 || same_type_p (TREE_TYPE (fn_type),
1039 TREE_TYPE (method_type))))
1043 if (DECL_CONTEXT (fn) == type)
1044 /* Defer to the local function. */
1046 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1047 error ("repeated using declaration %q+D", using_decl);
1049 error ("using declaration %q+D conflicts with a previous using declaration",
1054 error ("%q+#D cannot be overloaded", method);
1055 error ("with %q+#D", fn);
1058 /* We don't call duplicate_decls here to merge the
1059 declarations because that will confuse things if the
1060 methods have inline definitions. In particular, we
1061 will crash while processing the definitions. */
1067 /* A class should never have more than one destructor. */
1068 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1071 /* Add the new binding. */
1072 overload = build_overload (method, current_fns);
1075 TYPE_HAS_CONVERSION (type) = 1;
1076 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1077 push_class_level_binding (DECL_NAME (method), overload);
1081 /* We only expect to add few methods in the COMPLETE_P case, so
1082 just make room for one more method in that case. */
1083 if (VEC_reserve (tree, gc, method_vec, complete_p ? -1 : 1))
1084 CLASSTYPE_METHOD_VEC (type) = method_vec;
1085 if (slot == VEC_length (tree, method_vec))
1086 VEC_quick_push (tree, method_vec, overload);
1088 VEC_quick_insert (tree, method_vec, slot, overload);
1091 /* Replace the current slot. */
1092 VEC_replace (tree, method_vec, slot, overload);
1096 /* Subroutines of finish_struct. */
1098 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1099 legit, otherwise return 0. */
1102 alter_access (tree t, tree fdecl, tree access)
1106 if (!DECL_LANG_SPECIFIC (fdecl))
1107 retrofit_lang_decl (fdecl);
1109 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1111 elem = purpose_member (t, DECL_ACCESS (fdecl));
1114 if (TREE_VALUE (elem) != access)
1116 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1117 error ("conflicting access specifications for method"
1118 " %q+D, ignored", TREE_TYPE (fdecl));
1120 error ("conflicting access specifications for field %qE, ignored",
1125 /* They're changing the access to the same thing they changed
1126 it to before. That's OK. */
1132 perform_or_defer_access_check (TYPE_BINFO (t), fdecl);
1133 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1139 /* Process the USING_DECL, which is a member of T. */
1142 handle_using_decl (tree using_decl, tree t)
1144 tree decl = USING_DECL_DECLS (using_decl);
1145 tree name = DECL_NAME (using_decl);
1147 = TREE_PRIVATE (using_decl) ? access_private_node
1148 : TREE_PROTECTED (using_decl) ? access_protected_node
1149 : access_public_node;
1150 tree flist = NULL_TREE;
1153 gcc_assert (!processing_template_decl && decl);
1155 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1158 if (is_overloaded_fn (old_value))
1159 old_value = OVL_CURRENT (old_value);
1161 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1164 old_value = NULL_TREE;
1167 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1169 if (is_overloaded_fn (decl))
1174 else if (is_overloaded_fn (old_value))
1177 /* It's OK to use functions from a base when there are functions with
1178 the same name already present in the current class. */;
1181 error ("%q+D invalid in %q#T", using_decl, t);
1182 error (" because of local method %q+#D with same name",
1183 OVL_CURRENT (old_value));
1187 else if (!DECL_ARTIFICIAL (old_value))
1189 error ("%q+D invalid in %q#T", using_decl, t);
1190 error (" because of local member %q+#D with same name", old_value);
1194 /* Make type T see field decl FDECL with access ACCESS. */
1196 for (; flist; flist = OVL_NEXT (flist))
1198 add_method (t, OVL_CURRENT (flist), using_decl);
1199 alter_access (t, OVL_CURRENT (flist), access);
1202 alter_access (t, decl, access);
1205 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1206 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1207 properties of the bases. */
1210 check_bases (tree t,
1211 int* cant_have_const_ctor_p,
1212 int* no_const_asn_ref_p)
1215 int seen_non_virtual_nearly_empty_base_p;
1219 seen_non_virtual_nearly_empty_base_p = 0;
1221 for (binfo = TYPE_BINFO (t), i = 0;
1222 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1224 tree basetype = TREE_TYPE (base_binfo);
1226 gcc_assert (COMPLETE_TYPE_P (basetype));
1228 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1229 here because the case of virtual functions but non-virtual
1230 dtor is handled in finish_struct_1. */
1231 if (!TYPE_POLYMORPHIC_P (basetype))
1232 warning (OPT_Weffc__,
1233 "base class %q#T has a non-virtual destructor", basetype);
1235 /* If the base class doesn't have copy constructors or
1236 assignment operators that take const references, then the
1237 derived class cannot have such a member automatically
1239 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1240 *cant_have_const_ctor_p = 1;
1241 if (TYPE_HAS_ASSIGN_REF (basetype)
1242 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1243 *no_const_asn_ref_p = 1;
1245 if (BINFO_VIRTUAL_P (base_binfo))
1246 /* A virtual base does not effect nearly emptiness. */
1248 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1250 if (seen_non_virtual_nearly_empty_base_p)
1251 /* And if there is more than one nearly empty base, then the
1252 derived class is not nearly empty either. */
1253 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1255 /* Remember we've seen one. */
1256 seen_non_virtual_nearly_empty_base_p = 1;
1258 else if (!is_empty_class (basetype))
1259 /* If the base class is not empty or nearly empty, then this
1260 class cannot be nearly empty. */
1261 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1263 /* A lot of properties from the bases also apply to the derived
1265 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1266 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1267 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1268 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1269 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1270 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1271 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1272 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1273 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1277 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1278 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1279 that have had a nearly-empty virtual primary base stolen by some
1280 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1284 determine_primary_bases (tree t)
1287 tree primary = NULL_TREE;
1288 tree type_binfo = TYPE_BINFO (t);
1291 /* Determine the primary bases of our bases. */
1292 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1293 base_binfo = TREE_CHAIN (base_binfo))
1295 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1297 /* See if we're the non-virtual primary of our inheritance
1299 if (!BINFO_VIRTUAL_P (base_binfo))
1301 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1302 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1305 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1306 BINFO_TYPE (parent_primary)))
1307 /* We are the primary binfo. */
1308 BINFO_PRIMARY_P (base_binfo) = 1;
1310 /* Determine if we have a virtual primary base, and mark it so.
1312 if (primary && BINFO_VIRTUAL_P (primary))
1314 tree this_primary = copied_binfo (primary, base_binfo);
1316 if (BINFO_PRIMARY_P (this_primary))
1317 /* Someone already claimed this base. */
1318 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1323 BINFO_PRIMARY_P (this_primary) = 1;
1324 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1326 /* A virtual binfo might have been copied from within
1327 another hierarchy. As we're about to use it as a
1328 primary base, make sure the offsets match. */
1329 delta = size_diffop (convert (ssizetype,
1330 BINFO_OFFSET (base_binfo)),
1332 BINFO_OFFSET (this_primary)));
1334 propagate_binfo_offsets (this_primary, delta);
1339 /* First look for a dynamic direct non-virtual base. */
1340 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1342 tree basetype = BINFO_TYPE (base_binfo);
1344 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1346 primary = base_binfo;
1351 /* A "nearly-empty" virtual base class can be the primary base
1352 class, if no non-virtual polymorphic base can be found. Look for
1353 a nearly-empty virtual dynamic base that is not already a primary
1354 base of something in the hierarchy. If there is no such base,
1355 just pick the first nearly-empty virtual base. */
1357 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1358 base_binfo = TREE_CHAIN (base_binfo))
1359 if (BINFO_VIRTUAL_P (base_binfo)
1360 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1362 if (!BINFO_PRIMARY_P (base_binfo))
1364 /* Found one that is not primary. */
1365 primary = base_binfo;
1369 /* Remember the first candidate. */
1370 primary = base_binfo;
1374 /* If we've got a primary base, use it. */
1377 tree basetype = BINFO_TYPE (primary);
1379 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1380 if (BINFO_PRIMARY_P (primary))
1381 /* We are stealing a primary base. */
1382 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1383 BINFO_PRIMARY_P (primary) = 1;
1384 if (BINFO_VIRTUAL_P (primary))
1388 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1389 /* A virtual binfo might have been copied from within
1390 another hierarchy. As we're about to use it as a primary
1391 base, make sure the offsets match. */
1392 delta = size_diffop (ssize_int (0),
1393 convert (ssizetype, BINFO_OFFSET (primary)));
1395 propagate_binfo_offsets (primary, delta);
1398 primary = TYPE_BINFO (basetype);
1400 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1401 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1402 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1406 /* Set memoizing fields and bits of T (and its variants) for later
1410 finish_struct_bits (tree t)
1414 /* Fix up variants (if any). */
1415 for (variants = TYPE_NEXT_VARIANT (t);
1417 variants = TYPE_NEXT_VARIANT (variants))
1419 /* These fields are in the _TYPE part of the node, not in
1420 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1421 TYPE_HAS_CONSTRUCTOR (variants) = TYPE_HAS_CONSTRUCTOR (t);
1422 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1423 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1424 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1426 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1428 TYPE_BINFO (variants) = TYPE_BINFO (t);
1430 /* Copy whatever these are holding today. */
1431 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1432 TYPE_METHODS (variants) = TYPE_METHODS (t);
1433 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1436 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1437 /* For a class w/o baseclasses, 'finish_struct' has set
1438 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1439 Similarly for a class whose base classes do not have vtables.
1440 When neither of these is true, we might have removed abstract
1441 virtuals (by providing a definition), added some (by declaring
1442 new ones), or redeclared ones from a base class. We need to
1443 recalculate what's really an abstract virtual at this point (by
1444 looking in the vtables). */
1445 get_pure_virtuals (t);
1447 /* If this type has a copy constructor or a destructor, force its
1448 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1449 nonzero. This will cause it to be passed by invisible reference
1450 and prevent it from being returned in a register. */
1451 if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1454 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1455 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1457 TYPE_MODE (variants) = BLKmode;
1458 TREE_ADDRESSABLE (variants) = 1;
1463 /* Issue warnings about T having private constructors, but no friends,
1466 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1467 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1468 non-private static member functions. */
1471 maybe_warn_about_overly_private_class (tree t)
1473 int has_member_fn = 0;
1474 int has_nonprivate_method = 0;
1477 if (!warn_ctor_dtor_privacy
1478 /* If the class has friends, those entities might create and
1479 access instances, so we should not warn. */
1480 || (CLASSTYPE_FRIEND_CLASSES (t)
1481 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1482 /* We will have warned when the template was declared; there's
1483 no need to warn on every instantiation. */
1484 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1485 /* There's no reason to even consider warning about this
1489 /* We only issue one warning, if more than one applies, because
1490 otherwise, on code like:
1493 // Oops - forgot `public:'
1499 we warn several times about essentially the same problem. */
1501 /* Check to see if all (non-constructor, non-destructor) member
1502 functions are private. (Since there are no friends or
1503 non-private statics, we can't ever call any of the private member
1505 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1506 /* We're not interested in compiler-generated methods; they don't
1507 provide any way to call private members. */
1508 if (!DECL_ARTIFICIAL (fn))
1510 if (!TREE_PRIVATE (fn))
1512 if (DECL_STATIC_FUNCTION_P (fn))
1513 /* A non-private static member function is just like a
1514 friend; it can create and invoke private member
1515 functions, and be accessed without a class
1519 has_nonprivate_method = 1;
1520 /* Keep searching for a static member function. */
1522 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1526 if (!has_nonprivate_method && has_member_fn)
1528 /* There are no non-private methods, and there's at least one
1529 private member function that isn't a constructor or
1530 destructor. (If all the private members are
1531 constructors/destructors we want to use the code below that
1532 issues error messages specifically referring to
1533 constructors/destructors.) */
1535 tree binfo = TYPE_BINFO (t);
1537 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1538 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1540 has_nonprivate_method = 1;
1543 if (!has_nonprivate_method)
1545 warning (OPT_Wctor_dtor_privacy,
1546 "all member functions in class %qT are private", t);
1551 /* Even if some of the member functions are non-private, the class
1552 won't be useful for much if all the constructors or destructors
1553 are private: such an object can never be created or destroyed. */
1554 fn = CLASSTYPE_DESTRUCTORS (t);
1555 if (fn && TREE_PRIVATE (fn))
1557 warning (OPT_Wctor_dtor_privacy,
1558 "%q#T only defines a private destructor and has no friends",
1563 if (TYPE_HAS_CONSTRUCTOR (t)
1564 /* Implicitly generated constructors are always public. */
1565 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1566 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1568 int nonprivate_ctor = 0;
1570 /* If a non-template class does not define a copy
1571 constructor, one is defined for it, enabling it to avoid
1572 this warning. For a template class, this does not
1573 happen, and so we would normally get a warning on:
1575 template <class T> class C { private: C(); };
1577 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1578 complete non-template or fully instantiated classes have this
1580 if (!TYPE_HAS_INIT_REF (t))
1581 nonprivate_ctor = 1;
1583 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1585 tree ctor = OVL_CURRENT (fn);
1586 /* Ideally, we wouldn't count copy constructors (or, in
1587 fact, any constructor that takes an argument of the
1588 class type as a parameter) because such things cannot
1589 be used to construct an instance of the class unless
1590 you already have one. But, for now at least, we're
1592 if (! TREE_PRIVATE (ctor))
1594 nonprivate_ctor = 1;
1599 if (nonprivate_ctor == 0)
1601 warning (OPT_Wctor_dtor_privacy,
1602 "%q#T only defines private constructors and has no friends",
1610 gt_pointer_operator new_value;
1614 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1617 method_name_cmp (const void* m1_p, const void* m2_p)
1619 const tree *const m1 = (const tree *) m1_p;
1620 const tree *const m2 = (const tree *) m2_p;
1622 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1624 if (*m1 == NULL_TREE)
1626 if (*m2 == NULL_TREE)
1628 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1633 /* This routine compares two fields like method_name_cmp but using the
1634 pointer operator in resort_field_decl_data. */
1637 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1639 const tree *const m1 = (const tree *) m1_p;
1640 const tree *const m2 = (const tree *) m2_p;
1641 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1643 if (*m1 == NULL_TREE)
1645 if (*m2 == NULL_TREE)
1648 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1649 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1650 resort_data.new_value (&d1, resort_data.cookie);
1651 resort_data.new_value (&d2, resort_data.cookie);
1658 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1661 resort_type_method_vec (void* obj,
1662 void* orig_obj ATTRIBUTE_UNUSED ,
1663 gt_pointer_operator new_value,
1666 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1667 int len = VEC_length (tree, method_vec);
1671 /* The type conversion ops have to live at the front of the vec, so we
1673 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1674 VEC_iterate (tree, method_vec, slot, fn);
1676 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1681 resort_data.new_value = new_value;
1682 resort_data.cookie = cookie;
1683 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1684 resort_method_name_cmp);
1688 /* Warn about duplicate methods in fn_fields.
1690 Sort methods that are not special (i.e., constructors, destructors,
1691 and type conversion operators) so that we can find them faster in
1695 finish_struct_methods (tree t)
1698 VEC(tree,gc) *method_vec;
1701 method_vec = CLASSTYPE_METHOD_VEC (t);
1705 len = VEC_length (tree, method_vec);
1707 /* Clear DECL_IN_AGGR_P for all functions. */
1708 for (fn_fields = TYPE_METHODS (t); fn_fields;
1709 fn_fields = TREE_CHAIN (fn_fields))
1710 DECL_IN_AGGR_P (fn_fields) = 0;
1712 /* Issue warnings about private constructors and such. If there are
1713 no methods, then some public defaults are generated. */
1714 maybe_warn_about_overly_private_class (t);
1716 /* The type conversion ops have to live at the front of the vec, so we
1718 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1719 VEC_iterate (tree, method_vec, slot, fn_fields);
1721 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1724 qsort (VEC_address (tree, method_vec) + slot,
1725 len-slot, sizeof (tree), method_name_cmp);
1728 /* Make BINFO's vtable have N entries, including RTTI entries,
1729 vbase and vcall offsets, etc. Set its type and call the backend
1733 layout_vtable_decl (tree binfo, int n)
1738 atype = build_cplus_array_type (vtable_entry_type,
1739 build_index_type (size_int (n - 1)));
1740 layout_type (atype);
1742 /* We may have to grow the vtable. */
1743 vtable = get_vtbl_decl_for_binfo (binfo);
1744 if (!same_type_p (TREE_TYPE (vtable), atype))
1746 TREE_TYPE (vtable) = atype;
1747 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1748 layout_decl (vtable, 0);
1752 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1753 have the same signature. */
1756 same_signature_p (tree fndecl, tree base_fndecl)
1758 /* One destructor overrides another if they are the same kind of
1760 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1761 && special_function_p (base_fndecl) == special_function_p (fndecl))
1763 /* But a non-destructor never overrides a destructor, nor vice
1764 versa, nor do different kinds of destructors override
1765 one-another. For example, a complete object destructor does not
1766 override a deleting destructor. */
1767 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1770 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1771 || (DECL_CONV_FN_P (fndecl)
1772 && DECL_CONV_FN_P (base_fndecl)
1773 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1774 DECL_CONV_FN_TYPE (base_fndecl))))
1776 tree types, base_types;
1777 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1778 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1779 if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1780 == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1781 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1787 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1791 base_derived_from (tree derived, tree base)
1795 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1797 if (probe == derived)
1799 else if (BINFO_VIRTUAL_P (probe))
1800 /* If we meet a virtual base, we can't follow the inheritance
1801 any more. See if the complete type of DERIVED contains
1802 such a virtual base. */
1803 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1809 typedef struct find_final_overrider_data_s {
1810 /* The function for which we are trying to find a final overrider. */
1812 /* The base class in which the function was declared. */
1813 tree declaring_base;
1814 /* The candidate overriders. */
1816 /* Path to most derived. */
1817 VEC(tree,heap) *path;
1818 } find_final_overrider_data;
1820 /* Add the overrider along the current path to FFOD->CANDIDATES.
1821 Returns true if an overrider was found; false otherwise. */
1824 dfs_find_final_overrider_1 (tree binfo,
1825 find_final_overrider_data *ffod,
1830 /* If BINFO is not the most derived type, try a more derived class.
1831 A definition there will overrider a definition here. */
1835 if (dfs_find_final_overrider_1
1836 (VEC_index (tree, ffod->path, depth), ffod, depth))
1840 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1843 tree *candidate = &ffod->candidates;
1845 /* Remove any candidates overridden by this new function. */
1848 /* If *CANDIDATE overrides METHOD, then METHOD
1849 cannot override anything else on the list. */
1850 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1852 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1853 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1854 *candidate = TREE_CHAIN (*candidate);
1856 candidate = &TREE_CHAIN (*candidate);
1859 /* Add the new function. */
1860 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1867 /* Called from find_final_overrider via dfs_walk. */
1870 dfs_find_final_overrider_pre (tree binfo, void *data)
1872 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1874 if (binfo == ffod->declaring_base)
1875 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1876 VEC_safe_push (tree, heap, ffod->path, binfo);
1882 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1884 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1885 VEC_pop (tree, ffod->path);
1890 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1891 FN and whose TREE_VALUE is the binfo for the base where the
1892 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1893 DERIVED) is the base object in which FN is declared. */
1896 find_final_overrider (tree derived, tree binfo, tree fn)
1898 find_final_overrider_data ffod;
1900 /* Getting this right is a little tricky. This is valid:
1902 struct S { virtual void f (); };
1903 struct T { virtual void f (); };
1904 struct U : public S, public T { };
1906 even though calling `f' in `U' is ambiguous. But,
1908 struct R { virtual void f(); };
1909 struct S : virtual public R { virtual void f (); };
1910 struct T : virtual public R { virtual void f (); };
1911 struct U : public S, public T { };
1913 is not -- there's no way to decide whether to put `S::f' or
1914 `T::f' in the vtable for `R'.
1916 The solution is to look at all paths to BINFO. If we find
1917 different overriders along any two, then there is a problem. */
1918 if (DECL_THUNK_P (fn))
1919 fn = THUNK_TARGET (fn);
1921 /* Determine the depth of the hierarchy. */
1923 ffod.declaring_base = binfo;
1924 ffod.candidates = NULL_TREE;
1925 ffod.path = VEC_alloc (tree, heap, 30);
1927 dfs_walk_all (derived, dfs_find_final_overrider_pre,
1928 dfs_find_final_overrider_post, &ffod);
1930 VEC_free (tree, heap, ffod.path);
1932 /* If there was no winner, issue an error message. */
1933 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
1934 return error_mark_node;
1936 return ffod.candidates;
1939 /* Return the index of the vcall offset for FN when TYPE is used as a
1943 get_vcall_index (tree fn, tree type)
1945 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
1949 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
1950 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
1951 || same_signature_p (fn, p->purpose))
1954 /* There should always be an appropriate index. */
1958 /* Update an entry in the vtable for BINFO, which is in the hierarchy
1959 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
1960 corresponding position in the BINFO_VIRTUALS list. */
1963 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
1971 tree overrider_fn, overrider_target;
1972 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
1973 tree over_return, base_return;
1976 /* Find the nearest primary base (possibly binfo itself) which defines
1977 this function; this is the class the caller will convert to when
1978 calling FN through BINFO. */
1979 for (b = binfo; ; b = get_primary_binfo (b))
1982 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
1985 /* The nearest definition is from a lost primary. */
1986 if (BINFO_LOST_PRIMARY_P (b))
1991 /* Find the final overrider. */
1992 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
1993 if (overrider == error_mark_node)
1995 error ("no unique final overrider for %qD in %qT", target_fn, t);
1998 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2000 /* Check for adjusting covariant return types. */
2001 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2002 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2004 if (POINTER_TYPE_P (over_return)
2005 && TREE_CODE (over_return) == TREE_CODE (base_return)
2006 && CLASS_TYPE_P (TREE_TYPE (over_return))
2007 && CLASS_TYPE_P (TREE_TYPE (base_return))
2008 /* If the overrider is invalid, don't even try. */
2009 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2011 /* If FN is a covariant thunk, we must figure out the adjustment
2012 to the final base FN was converting to. As OVERRIDER_TARGET might
2013 also be converting to the return type of FN, we have to
2014 combine the two conversions here. */
2015 tree fixed_offset, virtual_offset;
2017 over_return = TREE_TYPE (over_return);
2018 base_return = TREE_TYPE (base_return);
2020 if (DECL_THUNK_P (fn))
2022 gcc_assert (DECL_RESULT_THUNK_P (fn));
2023 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2024 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2027 fixed_offset = virtual_offset = NULL_TREE;
2030 /* Find the equivalent binfo within the return type of the
2031 overriding function. We will want the vbase offset from
2033 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2035 else if (!same_type_ignoring_top_level_qualifiers_p
2036 (over_return, base_return))
2038 /* There was no existing virtual thunk (which takes
2039 precedence). So find the binfo of the base function's
2040 return type within the overriding function's return type.
2041 We cannot call lookup base here, because we're inside a
2042 dfs_walk, and will therefore clobber the BINFO_MARKED
2043 flags. Fortunately we know the covariancy is valid (it
2044 has already been checked), so we can just iterate along
2045 the binfos, which have been chained in inheritance graph
2046 order. Of course it is lame that we have to repeat the
2047 search here anyway -- we should really be caching pieces
2048 of the vtable and avoiding this repeated work. */
2049 tree thunk_binfo, base_binfo;
2051 /* Find the base binfo within the overriding function's
2052 return type. We will always find a thunk_binfo, except
2053 when the covariancy is invalid (which we will have
2054 already diagnosed). */
2055 for (base_binfo = TYPE_BINFO (base_return),
2056 thunk_binfo = TYPE_BINFO (over_return);
2058 thunk_binfo = TREE_CHAIN (thunk_binfo))
2059 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2060 BINFO_TYPE (base_binfo)))
2063 /* See if virtual inheritance is involved. */
2064 for (virtual_offset = thunk_binfo;
2066 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2067 if (BINFO_VIRTUAL_P (virtual_offset))
2071 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2073 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2077 /* We convert via virtual base. Adjust the fixed
2078 offset to be from there. */
2079 offset = size_diffop
2081 (ssizetype, BINFO_OFFSET (virtual_offset)));
2084 /* There was an existing fixed offset, this must be
2085 from the base just converted to, and the base the
2086 FN was thunking to. */
2087 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2089 fixed_offset = offset;
2093 if (fixed_offset || virtual_offset)
2094 /* Replace the overriding function with a covariant thunk. We
2095 will emit the overriding function in its own slot as
2097 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2098 fixed_offset, virtual_offset);
2101 gcc_assert (!DECL_THUNK_P (fn));
2103 /* Assume that we will produce a thunk that convert all the way to
2104 the final overrider, and not to an intermediate virtual base. */
2105 virtual_base = NULL_TREE;
2107 /* See if we can convert to an intermediate virtual base first, and then
2108 use the vcall offset located there to finish the conversion. */
2109 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2111 /* If we find the final overrider, then we can stop
2113 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2114 BINFO_TYPE (TREE_VALUE (overrider))))
2117 /* If we find a virtual base, and we haven't yet found the
2118 overrider, then there is a virtual base between the
2119 declaring base (first_defn) and the final overrider. */
2120 if (BINFO_VIRTUAL_P (b))
2127 if (overrider_fn != overrider_target && !virtual_base)
2129 /* The ABI specifies that a covariant thunk includes a mangling
2130 for a this pointer adjustment. This-adjusting thunks that
2131 override a function from a virtual base have a vcall
2132 adjustment. When the virtual base in question is a primary
2133 virtual base, we know the adjustments are zero, (and in the
2134 non-covariant case, we would not use the thunk).
2135 Unfortunately we didn't notice this could happen, when
2136 designing the ABI and so never mandated that such a covariant
2137 thunk should be emitted. Because we must use the ABI mandated
2138 name, we must continue searching from the binfo where we
2139 found the most recent definition of the function, towards the
2140 primary binfo which first introduced the function into the
2141 vtable. If that enters a virtual base, we must use a vcall
2142 this-adjusting thunk. Bleah! */
2143 tree probe = first_defn;
2145 while ((probe = get_primary_binfo (probe))
2146 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2147 if (BINFO_VIRTUAL_P (probe))
2148 virtual_base = probe;
2151 /* Even if we find a virtual base, the correct delta is
2152 between the overrider and the binfo we're building a vtable
2154 goto virtual_covariant;
2157 /* Compute the constant adjustment to the `this' pointer. The
2158 `this' pointer, when this function is called, will point at BINFO
2159 (or one of its primary bases, which are at the same offset). */
2161 /* The `this' pointer needs to be adjusted from the declaration to
2162 the nearest virtual base. */
2163 delta = size_diffop (convert (ssizetype, BINFO_OFFSET (virtual_base)),
2164 convert (ssizetype, BINFO_OFFSET (first_defn)));
2166 /* If the nearest definition is in a lost primary, we don't need an
2167 entry in our vtable. Except possibly in a constructor vtable,
2168 if we happen to get our primary back. In that case, the offset
2169 will be zero, as it will be a primary base. */
2170 delta = size_zero_node;
2172 /* The `this' pointer needs to be adjusted from pointing to
2173 BINFO to pointing at the base where the final overrider
2176 delta = size_diffop (convert (ssizetype,
2177 BINFO_OFFSET (TREE_VALUE (overrider))),
2178 convert (ssizetype, BINFO_OFFSET (binfo)));
2180 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2183 BV_VCALL_INDEX (*virtuals)
2184 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2186 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2189 /* Called from modify_all_vtables via dfs_walk. */
2192 dfs_modify_vtables (tree binfo, void* data)
2194 tree t = (tree) data;
2199 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2200 /* A base without a vtable needs no modification, and its bases
2201 are uninteresting. */
2202 return dfs_skip_bases;
2204 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2205 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2206 /* Don't do the primary vtable, if it's new. */
2209 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2210 /* There's no need to modify the vtable for a non-virtual primary
2211 base; we're not going to use that vtable anyhow. We do still
2212 need to do this for virtual primary bases, as they could become
2213 non-primary in a construction vtable. */
2216 make_new_vtable (t, binfo);
2218 /* Now, go through each of the virtual functions in the virtual
2219 function table for BINFO. Find the final overrider, and update
2220 the BINFO_VIRTUALS list appropriately. */
2221 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2222 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2224 ix++, virtuals = TREE_CHAIN (virtuals),
2225 old_virtuals = TREE_CHAIN (old_virtuals))
2226 update_vtable_entry_for_fn (t,
2228 BV_FN (old_virtuals),
2234 /* Update all of the primary and secondary vtables for T. Create new
2235 vtables as required, and initialize their RTTI information. Each
2236 of the functions in VIRTUALS is declared in T and may override a
2237 virtual function from a base class; find and modify the appropriate
2238 entries to point to the overriding functions. Returns a list, in
2239 declaration order, of the virtual functions that are declared in T,
2240 but do not appear in the primary base class vtable, and which
2241 should therefore be appended to the end of the vtable for T. */
2244 modify_all_vtables (tree t, tree virtuals)
2246 tree binfo = TYPE_BINFO (t);
2249 /* Update all of the vtables. */
2250 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2252 /* Add virtual functions not already in our primary vtable. These
2253 will be both those introduced by this class, and those overridden
2254 from secondary bases. It does not include virtuals merely
2255 inherited from secondary bases. */
2256 for (fnsp = &virtuals; *fnsp; )
2258 tree fn = TREE_VALUE (*fnsp);
2260 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2261 || DECL_VINDEX (fn) == error_mark_node)
2263 /* We don't need to adjust the `this' pointer when
2264 calling this function. */
2265 BV_DELTA (*fnsp) = integer_zero_node;
2266 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2268 /* This is a function not already in our vtable. Keep it. */
2269 fnsp = &TREE_CHAIN (*fnsp);
2272 /* We've already got an entry for this function. Skip it. */
2273 *fnsp = TREE_CHAIN (*fnsp);
2279 /* Get the base virtual function declarations in T that have the
2283 get_basefndecls (tree name, tree t)
2286 tree base_fndecls = NULL_TREE;
2287 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2290 /* Find virtual functions in T with the indicated NAME. */
2291 i = lookup_fnfields_1 (t, name);
2293 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2295 methods = OVL_NEXT (methods))
2297 tree method = OVL_CURRENT (methods);
2299 if (TREE_CODE (method) == FUNCTION_DECL
2300 && DECL_VINDEX (method))
2301 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2305 return base_fndecls;
2307 for (i = 0; i < n_baseclasses; i++)
2309 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2310 base_fndecls = chainon (get_basefndecls (name, basetype),
2314 return base_fndecls;
2317 /* If this declaration supersedes the declaration of
2318 a method declared virtual in the base class, then
2319 mark this field as being virtual as well. */
2322 check_for_override (tree decl, tree ctype)
2324 if (TREE_CODE (decl) == TEMPLATE_DECL)
2325 /* In [temp.mem] we have:
2327 A specialization of a member function template does not
2328 override a virtual function from a base class. */
2330 if ((DECL_DESTRUCTOR_P (decl)
2331 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2332 || DECL_CONV_FN_P (decl))
2333 && look_for_overrides (ctype, decl)
2334 && !DECL_STATIC_FUNCTION_P (decl))
2335 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2336 the error_mark_node so that we know it is an overriding
2338 DECL_VINDEX (decl) = decl;
2340 if (DECL_VIRTUAL_P (decl))
2342 if (!DECL_VINDEX (decl))
2343 DECL_VINDEX (decl) = error_mark_node;
2344 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2348 /* Warn about hidden virtual functions that are not overridden in t.
2349 We know that constructors and destructors don't apply. */
2352 warn_hidden (tree t)
2354 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2358 /* We go through each separately named virtual function. */
2359 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2360 VEC_iterate (tree, method_vec, i, fns);
2371 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2372 have the same name. Figure out what name that is. */
2373 name = DECL_NAME (OVL_CURRENT (fns));
2374 /* There are no possibly hidden functions yet. */
2375 base_fndecls = NULL_TREE;
2376 /* Iterate through all of the base classes looking for possibly
2377 hidden functions. */
2378 for (binfo = TYPE_BINFO (t), j = 0;
2379 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2381 tree basetype = BINFO_TYPE (base_binfo);
2382 base_fndecls = chainon (get_basefndecls (name, basetype),
2386 /* If there are no functions to hide, continue. */
2390 /* Remove any overridden functions. */
2391 for (fn = fns; fn; fn = OVL_NEXT (fn))
2393 fndecl = OVL_CURRENT (fn);
2394 if (DECL_VINDEX (fndecl))
2396 tree *prev = &base_fndecls;
2399 /* If the method from the base class has the same
2400 signature as the method from the derived class, it
2401 has been overridden. */
2402 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2403 *prev = TREE_CHAIN (*prev);
2405 prev = &TREE_CHAIN (*prev);
2409 /* Now give a warning for all base functions without overriders,
2410 as they are hidden. */
2411 while (base_fndecls)
2413 /* Here we know it is a hider, and no overrider exists. */
2414 warning (0, "%q+D was hidden", TREE_VALUE (base_fndecls));
2415 warning (0, " by %q+D", fns);
2416 base_fndecls = TREE_CHAIN (base_fndecls);
2421 /* Check for things that are invalid. There are probably plenty of other
2422 things we should check for also. */
2425 finish_struct_anon (tree t)
2429 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2431 if (TREE_STATIC (field))
2433 if (TREE_CODE (field) != FIELD_DECL)
2436 if (DECL_NAME (field) == NULL_TREE
2437 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2439 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2440 for (; elt; elt = TREE_CHAIN (elt))
2442 /* We're generally only interested in entities the user
2443 declared, but we also find nested classes by noticing
2444 the TYPE_DECL that we create implicitly. You're
2445 allowed to put one anonymous union inside another,
2446 though, so we explicitly tolerate that. We use
2447 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2448 we also allow unnamed types used for defining fields. */
2449 if (DECL_ARTIFICIAL (elt)
2450 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2451 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2454 if (TREE_CODE (elt) != FIELD_DECL)
2456 pedwarn ("%q+#D invalid; an anonymous union can "
2457 "only have non-static data members", elt);
2461 if (TREE_PRIVATE (elt))
2462 pedwarn ("private member %q+#D in anonymous union", elt);
2463 else if (TREE_PROTECTED (elt))
2464 pedwarn ("protected member %q+#D in anonymous union", elt);
2466 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2467 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2473 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2474 will be used later during class template instantiation.
2475 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2476 a non-static member data (FIELD_DECL), a member function
2477 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2478 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2479 When FRIEND_P is nonzero, T is either a friend class
2480 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2481 (FUNCTION_DECL, TEMPLATE_DECL). */
2484 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2486 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2487 if (CLASSTYPE_TEMPLATE_INFO (type))
2488 CLASSTYPE_DECL_LIST (type)
2489 = tree_cons (friend_p ? NULL_TREE : type,
2490 t, CLASSTYPE_DECL_LIST (type));
2493 /* Create default constructors, assignment operators, and so forth for
2494 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2495 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2496 the class cannot have a default constructor, copy constructor
2497 taking a const reference argument, or an assignment operator taking
2498 a const reference, respectively. */
2501 add_implicitly_declared_members (tree t,
2502 int cant_have_const_cctor,
2503 int cant_have_const_assignment)
2506 if (!CLASSTYPE_DESTRUCTORS (t))
2508 /* In general, we create destructors lazily. */
2509 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2510 /* However, if the implicit destructor is non-trivial
2511 destructor, we sometimes have to create it at this point. */
2512 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2516 if (TYPE_FOR_JAVA (t))
2517 /* If this a Java class, any non-trivial destructor is
2518 invalid, even if compiler-generated. Therefore, if the
2519 destructor is non-trivial we create it now. */
2527 /* If the implicit destructor will be virtual, then we must
2528 generate it now because (unfortunately) we do not
2529 generate virtual tables lazily. */
2530 binfo = TYPE_BINFO (t);
2531 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2536 base_type = BINFO_TYPE (base_binfo);
2537 dtor = CLASSTYPE_DESTRUCTORS (base_type);
2538 if (dtor && DECL_VIRTUAL_P (dtor))
2546 /* If we can't get away with being lazy, generate the destructor
2549 lazily_declare_fn (sfk_destructor, t);
2553 /* Default constructor. */
2554 if (! TYPE_HAS_CONSTRUCTOR (t))
2556 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2557 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2560 /* Copy constructor. */
2561 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2563 TYPE_HAS_INIT_REF (t) = 1;
2564 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2565 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2566 TYPE_HAS_CONSTRUCTOR (t) = 1;
2569 /* If there is no assignment operator, one will be created if and
2570 when it is needed. For now, just record whether or not the type
2571 of the parameter to the assignment operator will be a const or
2572 non-const reference. */
2573 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2575 TYPE_HAS_ASSIGN_REF (t) = 1;
2576 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2577 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2581 /* Subroutine of finish_struct_1. Recursively count the number of fields
2582 in TYPE, including anonymous union members. */
2585 count_fields (tree fields)
2589 for (x = fields; x; x = TREE_CHAIN (x))
2591 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2592 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2599 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2600 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2603 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2606 for (x = fields; x; x = TREE_CHAIN (x))
2608 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2609 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2611 field_vec->elts[idx++] = x;
2616 /* FIELD is a bit-field. We are finishing the processing for its
2617 enclosing type. Issue any appropriate messages and set appropriate
2621 check_bitfield_decl (tree field)
2623 tree type = TREE_TYPE (field);
2626 /* Extract the declared width of the bitfield, which has been
2627 temporarily stashed in DECL_INITIAL. */
2628 w = DECL_INITIAL (field);
2629 gcc_assert (w != NULL_TREE);
2630 /* Remove the bit-field width indicator so that the rest of the
2631 compiler does not treat that value as an initializer. */
2632 DECL_INITIAL (field) = NULL_TREE;
2634 /* Detect invalid bit-field type. */
2635 if (!INTEGRAL_TYPE_P (type))
2637 error ("bit-field %q+#D with non-integral type", field);
2638 TREE_TYPE (field) = error_mark_node;
2639 w = error_mark_node;
2643 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2646 /* detect invalid field size. */
2647 w = integral_constant_value (w);
2649 if (TREE_CODE (w) != INTEGER_CST)
2651 error ("bit-field %q+D width not an integer constant", field);
2652 w = error_mark_node;
2654 else if (tree_int_cst_sgn (w) < 0)
2656 error ("negative width in bit-field %q+D", field);
2657 w = error_mark_node;
2659 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2661 error ("zero width for bit-field %q+D", field);
2662 w = error_mark_node;
2664 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2665 && TREE_CODE (type) != ENUMERAL_TYPE
2666 && TREE_CODE (type) != BOOLEAN_TYPE)
2667 warning (0, "width of %q+D exceeds its type", field);
2668 else if (TREE_CODE (type) == ENUMERAL_TYPE
2669 && (0 > compare_tree_int (w,
2670 min_precision (TYPE_MIN_VALUE (type),
2671 TYPE_UNSIGNED (type)))
2672 || 0 > compare_tree_int (w,
2674 (TYPE_MAX_VALUE (type),
2675 TYPE_UNSIGNED (type)))))
2676 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2679 if (w != error_mark_node)
2681 DECL_SIZE (field) = convert (bitsizetype, w);
2682 DECL_BIT_FIELD (field) = 1;
2686 /* Non-bit-fields are aligned for their type. */
2687 DECL_BIT_FIELD (field) = 0;
2688 CLEAR_DECL_C_BIT_FIELD (field);
2692 /* FIELD is a non bit-field. We are finishing the processing for its
2693 enclosing type T. Issue any appropriate messages and set appropriate
2697 check_field_decl (tree field,
2699 int* cant_have_const_ctor,
2700 int* no_const_asn_ref,
2701 int* any_default_members)
2703 tree type = strip_array_types (TREE_TYPE (field));
2705 /* An anonymous union cannot contain any fields which would change
2706 the settings of CANT_HAVE_CONST_CTOR and friends. */
2707 if (ANON_UNION_TYPE_P (type))
2709 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2710 structs. So, we recurse through their fields here. */
2711 else if (ANON_AGGR_TYPE_P (type))
2715 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2716 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2717 check_field_decl (fields, t, cant_have_const_ctor,
2718 no_const_asn_ref, any_default_members);
2720 /* Check members with class type for constructors, destructors,
2722 else if (CLASS_TYPE_P (type))
2724 /* Never let anything with uninheritable virtuals
2725 make it through without complaint. */
2726 abstract_virtuals_error (field, type);
2728 if (TREE_CODE (t) == UNION_TYPE)
2730 if (TYPE_NEEDS_CONSTRUCTING (type))
2731 error ("member %q+#D with constructor not allowed in union",
2733 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2734 error ("member %q+#D with destructor not allowed in union", field);
2735 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2736 error ("member %q+#D with copy assignment operator not allowed in union",
2741 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2742 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2743 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2744 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2745 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2748 if (!TYPE_HAS_CONST_INIT_REF (type))
2749 *cant_have_const_ctor = 1;
2751 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2752 *no_const_asn_ref = 1;
2754 if (DECL_INITIAL (field) != NULL_TREE)
2756 /* `build_class_init_list' does not recognize
2758 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2759 error ("multiple fields in union %qT initialized", t);
2760 *any_default_members = 1;
2764 /* Check the data members (both static and non-static), class-scoped
2765 typedefs, etc., appearing in the declaration of T. Issue
2766 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2767 declaration order) of access declarations; each TREE_VALUE in this
2768 list is a USING_DECL.
2770 In addition, set the following flags:
2773 The class is empty, i.e., contains no non-static data members.
2775 CANT_HAVE_CONST_CTOR_P
2776 This class cannot have an implicitly generated copy constructor
2777 taking a const reference.
2779 CANT_HAVE_CONST_ASN_REF
2780 This class cannot have an implicitly generated assignment
2781 operator taking a const reference.
2783 All of these flags should be initialized before calling this
2786 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2787 fields can be added by adding to this chain. */
2790 check_field_decls (tree t, tree *access_decls,
2791 int *cant_have_const_ctor_p,
2792 int *no_const_asn_ref_p)
2797 int any_default_members;
2799 /* Assume there are no access declarations. */
2800 *access_decls = NULL_TREE;
2801 /* Assume this class has no pointer members. */
2802 has_pointers = false;
2803 /* Assume none of the members of this class have default
2805 any_default_members = 0;
2807 for (field = &TYPE_FIELDS (t); *field; field = next)
2810 tree type = TREE_TYPE (x);
2812 next = &TREE_CHAIN (x);
2814 if (TREE_CODE (x) == USING_DECL)
2816 /* Prune the access declaration from the list of fields. */
2817 *field = TREE_CHAIN (x);
2819 /* Save the access declarations for our caller. */
2820 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2822 /* Since we've reset *FIELD there's no reason to skip to the
2828 if (TREE_CODE (x) == TYPE_DECL
2829 || TREE_CODE (x) == TEMPLATE_DECL)
2832 /* If we've gotten this far, it's a data member, possibly static,
2833 or an enumerator. */
2834 DECL_CONTEXT (x) = t;
2836 /* When this goes into scope, it will be a non-local reference. */
2837 DECL_NONLOCAL (x) = 1;
2839 if (TREE_CODE (t) == UNION_TYPE)
2843 If a union contains a static data member, or a member of
2844 reference type, the program is ill-formed. */
2845 if (TREE_CODE (x) == VAR_DECL)
2847 error ("%q+D may not be static because it is a member of a union", x);
2850 if (TREE_CODE (type) == REFERENCE_TYPE)
2852 error ("%q+D may not have reference type %qT because"
2853 " it is a member of a union",
2859 /* Perform error checking that did not get done in
2861 if (TREE_CODE (type) == FUNCTION_TYPE)
2863 error ("field %q+D invalidly declared function type", x);
2864 type = build_pointer_type (type);
2865 TREE_TYPE (x) = type;
2867 else if (TREE_CODE (type) == METHOD_TYPE)
2869 error ("field %q+D invalidly declared method type", x);
2870 type = build_pointer_type (type);
2871 TREE_TYPE (x) = type;
2874 if (type == error_mark_node)
2877 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
2880 /* Now it can only be a FIELD_DECL. */
2882 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
2883 CLASSTYPE_NON_AGGREGATE (t) = 1;
2885 /* If this is of reference type, check if it needs an init.
2886 Also do a little ANSI jig if necessary. */
2887 if (TREE_CODE (type) == REFERENCE_TYPE)
2889 CLASSTYPE_NON_POD_P (t) = 1;
2890 if (DECL_INITIAL (x) == NULL_TREE)
2891 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2893 /* ARM $12.6.2: [A member initializer list] (or, for an
2894 aggregate, initialization by a brace-enclosed list) is the
2895 only way to initialize nonstatic const and reference
2897 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2899 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
2901 warning (OPT_Wextra, "non-static reference %q+#D in class without a constructor", x);
2904 type = strip_array_types (type);
2906 if (TYPE_PACKED (t))
2908 if (!pod_type_p (type) && !TYPE_PACKED (type))
2912 "ignoring packed attribute because of unpacked non-POD field %q+#D",
2914 TYPE_PACKED (t) = 0;
2916 else if (TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
2917 DECL_PACKED (x) = 1;
2920 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
2921 /* We don't treat zero-width bitfields as making a class
2926 /* The class is non-empty. */
2927 CLASSTYPE_EMPTY_P (t) = 0;
2928 /* The class is not even nearly empty. */
2929 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
2930 /* If one of the data members contains an empty class,
2932 if (CLASS_TYPE_P (type)
2933 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
2934 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
2937 /* This is used by -Weffc++ (see below). Warn only for pointers
2938 to members which might hold dynamic memory. So do not warn
2939 for pointers to functions or pointers to members. */
2940 if (TYPE_PTR_P (type)
2941 && !TYPE_PTRFN_P (type)
2942 && !TYPE_PTR_TO_MEMBER_P (type))
2943 has_pointers = true;
2945 if (CLASS_TYPE_P (type))
2947 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
2948 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2949 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
2950 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
2953 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
2954 CLASSTYPE_HAS_MUTABLE (t) = 1;
2956 if (! pod_type_p (type))
2957 /* DR 148 now allows pointers to members (which are POD themselves),
2958 to be allowed in POD structs. */
2959 CLASSTYPE_NON_POD_P (t) = 1;
2961 if (! zero_init_p (type))
2962 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
2964 /* If any field is const, the structure type is pseudo-const. */
2965 if (CP_TYPE_CONST_P (type))
2967 C_TYPE_FIELDS_READONLY (t) = 1;
2968 if (DECL_INITIAL (x) == NULL_TREE)
2969 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
2971 /* ARM $12.6.2: [A member initializer list] (or, for an
2972 aggregate, initialization by a brace-enclosed list) is the
2973 only way to initialize nonstatic const and reference
2975 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2977 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
2979 warning (OPT_Wextra, "non-static const member %q+#D in class without a constructor", x);
2981 /* A field that is pseudo-const makes the structure likewise. */
2982 else if (CLASS_TYPE_P (type))
2984 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
2985 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
2986 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
2987 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
2990 /* Core issue 80: A nonstatic data member is required to have a
2991 different name from the class iff the class has a
2992 user-defined constructor. */
2993 if (constructor_name_p (DECL_NAME (x), t) && TYPE_HAS_CONSTRUCTOR (t))
2994 pedwarn ("field %q+#D with same name as class", x);
2996 /* We set DECL_C_BIT_FIELD in grokbitfield.
2997 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
2998 if (DECL_C_BIT_FIELD (x))
2999 check_bitfield_decl (x);
3001 check_field_decl (x, t,
3002 cant_have_const_ctor_p,
3004 &any_default_members);
3007 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3008 it should also define a copy constructor and an assignment operator to
3009 implement the correct copy semantic (deep vs shallow, etc.). As it is
3010 not feasible to check whether the constructors do allocate dynamic memory
3011 and store it within members, we approximate the warning like this:
3013 -- Warn only if there are members which are pointers
3014 -- Warn only if there is a non-trivial constructor (otherwise,
3015 there cannot be memory allocated).
3016 -- Warn only if there is a non-trivial destructor. We assume that the
3017 user at least implemented the cleanup correctly, and a destructor
3018 is needed to free dynamic memory.
3020 This seems enough for practical purposes. */
3023 && TYPE_HAS_CONSTRUCTOR (t)
3024 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3025 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3027 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3029 if (! TYPE_HAS_INIT_REF (t))
3031 warning (OPT_Weffc__,
3032 " but does not override %<%T(const %T&)%>", t, t);
3033 if (!TYPE_HAS_ASSIGN_REF (t))
3034 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3036 else if (! TYPE_HAS_ASSIGN_REF (t))
3037 warning (OPT_Weffc__,
3038 " but does not override %<operator=(const %T&)%>", t);
3042 /* Check anonymous struct/anonymous union fields. */
3043 finish_struct_anon (t);
3045 /* We've built up the list of access declarations in reverse order.
3047 *access_decls = nreverse (*access_decls);
3050 /* If TYPE is an empty class type, records its OFFSET in the table of
3054 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3058 if (!is_empty_class (type))
3061 /* Record the location of this empty object in OFFSETS. */
3062 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3064 n = splay_tree_insert (offsets,
3065 (splay_tree_key) offset,
3066 (splay_tree_value) NULL_TREE);
3067 n->value = ((splay_tree_value)
3068 tree_cons (NULL_TREE,
3075 /* Returns nonzero if TYPE is an empty class type and there is
3076 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3079 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3084 if (!is_empty_class (type))
3087 /* Record the location of this empty object in OFFSETS. */
3088 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3092 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3093 if (same_type_p (TREE_VALUE (t), type))
3099 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3100 F for every subobject, passing it the type, offset, and table of
3101 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3104 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3105 than MAX_OFFSET will not be walked.
3107 If F returns a nonzero value, the traversal ceases, and that value
3108 is returned. Otherwise, returns zero. */
3111 walk_subobject_offsets (tree type,
3112 subobject_offset_fn f,
3119 tree type_binfo = NULL_TREE;
3121 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3123 if (max_offset && INT_CST_LT (max_offset, offset))
3126 if (type == error_mark_node)
3131 if (abi_version_at_least (2))
3133 type = BINFO_TYPE (type);
3136 if (CLASS_TYPE_P (type))
3142 /* Avoid recursing into objects that are not interesting. */
3143 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3146 /* Record the location of TYPE. */
3147 r = (*f) (type, offset, offsets);
3151 /* Iterate through the direct base classes of TYPE. */
3153 type_binfo = TYPE_BINFO (type);
3154 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3158 if (abi_version_at_least (2)
3159 && BINFO_VIRTUAL_P (binfo))
3163 && BINFO_VIRTUAL_P (binfo)
3164 && !BINFO_PRIMARY_P (binfo))
3167 if (!abi_version_at_least (2))
3168 binfo_offset = size_binop (PLUS_EXPR,
3170 BINFO_OFFSET (binfo));
3174 /* We cannot rely on BINFO_OFFSET being set for the base
3175 class yet, but the offsets for direct non-virtual
3176 bases can be calculated by going back to the TYPE. */
3177 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3178 binfo_offset = size_binop (PLUS_EXPR,
3180 BINFO_OFFSET (orig_binfo));
3183 r = walk_subobject_offsets (binfo,
3188 (abi_version_at_least (2)
3189 ? /*vbases_p=*/0 : vbases_p));
3194 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3197 VEC(tree,gc) *vbases;
3199 /* Iterate through the virtual base classes of TYPE. In G++
3200 3.2, we included virtual bases in the direct base class
3201 loop above, which results in incorrect results; the
3202 correct offsets for virtual bases are only known when
3203 working with the most derived type. */
3205 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3206 VEC_iterate (tree, vbases, ix, binfo); ix++)
3208 r = walk_subobject_offsets (binfo,
3210 size_binop (PLUS_EXPR,
3212 BINFO_OFFSET (binfo)),
3221 /* We still have to walk the primary base, if it is
3222 virtual. (If it is non-virtual, then it was walked
3224 tree vbase = get_primary_binfo (type_binfo);
3226 if (vbase && BINFO_VIRTUAL_P (vbase)
3227 && BINFO_PRIMARY_P (vbase)
3228 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3230 r = (walk_subobject_offsets
3232 offsets, max_offset, /*vbases_p=*/0));
3239 /* Iterate through the fields of TYPE. */
3240 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3241 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3245 if (abi_version_at_least (2))
3246 field_offset = byte_position (field);
3248 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3249 field_offset = DECL_FIELD_OFFSET (field);
3251 r = walk_subobject_offsets (TREE_TYPE (field),
3253 size_binop (PLUS_EXPR,
3263 else if (TREE_CODE (type) == ARRAY_TYPE)
3265 tree element_type = strip_array_types (type);
3266 tree domain = TYPE_DOMAIN (type);
3269 /* Avoid recursing into objects that are not interesting. */
3270 if (!CLASS_TYPE_P (element_type)
3271 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3274 /* Step through each of the elements in the array. */
3275 for (index = size_zero_node;
3276 /* G++ 3.2 had an off-by-one error here. */
3277 (abi_version_at_least (2)
3278 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3279 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3280 index = size_binop (PLUS_EXPR, index, size_one_node))
3282 r = walk_subobject_offsets (TREE_TYPE (type),
3290 offset = size_binop (PLUS_EXPR, offset,
3291 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3292 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3293 there's no point in iterating through the remaining
3294 elements of the array. */
3295 if (max_offset && INT_CST_LT (max_offset, offset))
3303 /* Record all of the empty subobjects of TYPE (either a type or a
3304 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3305 is being placed at OFFSET; otherwise, it is a base class that is
3306 being placed at OFFSET. */
3309 record_subobject_offsets (tree type,
3312 bool is_data_member)
3315 /* If recording subobjects for a non-static data member or a
3316 non-empty base class , we do not need to record offsets beyond
3317 the size of the biggest empty class. Additional data members
3318 will go at the end of the class. Additional base classes will go
3319 either at offset zero (if empty, in which case they cannot
3320 overlap with offsets past the size of the biggest empty class) or
3321 at the end of the class.
3323 However, if we are placing an empty base class, then we must record
3324 all offsets, as either the empty class is at offset zero (where
3325 other empty classes might later be placed) or at the end of the
3326 class (where other objects might then be placed, so other empty
3327 subobjects might later overlap). */
3329 || !is_empty_class (BINFO_TYPE (type)))
3330 max_offset = sizeof_biggest_empty_class;
3332 max_offset = NULL_TREE;
3333 walk_subobject_offsets (type, record_subobject_offset, offset,
3334 offsets, max_offset, is_data_member);
3337 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3338 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3339 virtual bases of TYPE are examined. */
3342 layout_conflict_p (tree type,
3347 splay_tree_node max_node;
3349 /* Get the node in OFFSETS that indicates the maximum offset where
3350 an empty subobject is located. */
3351 max_node = splay_tree_max (offsets);
3352 /* If there aren't any empty subobjects, then there's no point in
3353 performing this check. */
3357 return walk_subobject_offsets (type, check_subobject_offset, offset,
3358 offsets, (tree) (max_node->key),
3362 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3363 non-static data member of the type indicated by RLI. BINFO is the
3364 binfo corresponding to the base subobject, OFFSETS maps offsets to
3365 types already located at those offsets. This function determines
3366 the position of the DECL. */
3369 layout_nonempty_base_or_field (record_layout_info rli,
3374 tree offset = NULL_TREE;
3380 /* For the purposes of determining layout conflicts, we want to
3381 use the class type of BINFO; TREE_TYPE (DECL) will be the
3382 CLASSTYPE_AS_BASE version, which does not contain entries for
3383 zero-sized bases. */
3384 type = TREE_TYPE (binfo);
3389 type = TREE_TYPE (decl);
3393 /* Try to place the field. It may take more than one try if we have
3394 a hard time placing the field without putting two objects of the
3395 same type at the same address. */
3398 struct record_layout_info_s old_rli = *rli;
3400 /* Place this field. */
3401 place_field (rli, decl);
3402 offset = byte_position (decl);
3404 /* We have to check to see whether or not there is already
3405 something of the same type at the offset we're about to use.
3406 For example, consider:
3409 struct T : public S { int i; };
3410 struct U : public S, public T {};
3412 Here, we put S at offset zero in U. Then, we can't put T at
3413 offset zero -- its S component would be at the same address
3414 as the S we already allocated. So, we have to skip ahead.
3415 Since all data members, including those whose type is an
3416 empty class, have nonzero size, any overlap can happen only
3417 with a direct or indirect base-class -- it can't happen with
3419 /* In a union, overlap is permitted; all members are placed at
3421 if (TREE_CODE (rli->t) == UNION_TYPE)
3423 /* G++ 3.2 did not check for overlaps when placing a non-empty
3425 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3427 if (layout_conflict_p (field_p ? type : binfo, offset,
3430 /* Strip off the size allocated to this field. That puts us
3431 at the first place we could have put the field with
3432 proper alignment. */
3435 /* Bump up by the alignment required for the type. */
3437 = size_binop (PLUS_EXPR, rli->bitpos,
3439 ? CLASSTYPE_ALIGN (type)
3440 : TYPE_ALIGN (type)));
3441 normalize_rli (rli);
3444 /* There was no conflict. We're done laying out this field. */
3448 /* Now that we know where it will be placed, update its
3450 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3451 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3452 this point because their BINFO_OFFSET is copied from another
3453 hierarchy. Therefore, we may not need to add the entire
3455 propagate_binfo_offsets (binfo,
3456 size_diffop (convert (ssizetype, offset),
3458 BINFO_OFFSET (binfo))));
3461 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3464 empty_base_at_nonzero_offset_p (tree type,
3466 splay_tree offsets ATTRIBUTE_UNUSED)
3468 return is_empty_class (type) && !integer_zerop (offset);
3471 /* Layout the empty base BINFO. EOC indicates the byte currently just
3472 past the end of the class, and should be correctly aligned for a
3473 class of the type indicated by BINFO; OFFSETS gives the offsets of
3474 the empty bases allocated so far. T is the most derived
3475 type. Return nonzero iff we added it at the end. */
3478 layout_empty_base (tree binfo, tree eoc, splay_tree offsets)
3481 tree basetype = BINFO_TYPE (binfo);
3484 /* This routine should only be used for empty classes. */
3485 gcc_assert (is_empty_class (basetype));
3486 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3488 if (!integer_zerop (BINFO_OFFSET (binfo)))
3490 if (abi_version_at_least (2))
3491 propagate_binfo_offsets
3492 (binfo, size_diffop (size_zero_node, BINFO_OFFSET (binfo)));
3495 "offset of empty base %qT may not be ABI-compliant and may"
3496 "change in a future version of GCC",
3497 BINFO_TYPE (binfo));
3500 /* This is an empty base class. We first try to put it at offset
3502 if (layout_conflict_p (binfo,
3503 BINFO_OFFSET (binfo),
3507 /* That didn't work. Now, we move forward from the next
3508 available spot in the class. */
3510 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3513 if (!layout_conflict_p (binfo,
3514 BINFO_OFFSET (binfo),
3517 /* We finally found a spot where there's no overlap. */
3520 /* There's overlap here, too. Bump along to the next spot. */
3521 propagate_binfo_offsets (binfo, alignment);
3527 /* Layout the base given by BINFO in the class indicated by RLI.
3528 *BASE_ALIGN is a running maximum of the alignments of
3529 any base class. OFFSETS gives the location of empty base
3530 subobjects. T is the most derived type. Return nonzero if the new
3531 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3532 *NEXT_FIELD, unless BINFO is for an empty base class.
3534 Returns the location at which the next field should be inserted. */
3537 build_base_field (record_layout_info rli, tree binfo,
3538 splay_tree offsets, tree *next_field)
3541 tree basetype = BINFO_TYPE (binfo);
3543 if (!COMPLETE_TYPE_P (basetype))
3544 /* This error is now reported in xref_tag, thus giving better
3545 location information. */
3548 /* Place the base class. */
3549 if (!is_empty_class (basetype))
3553 /* The containing class is non-empty because it has a non-empty
3555 CLASSTYPE_EMPTY_P (t) = 0;
3557 /* Create the FIELD_DECL. */
3558 decl = build_decl (FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3559 DECL_ARTIFICIAL (decl) = 1;
3560 DECL_IGNORED_P (decl) = 1;
3561 DECL_FIELD_CONTEXT (decl) = t;
3562 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3563 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3564 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3565 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3566 DECL_MODE (decl) = TYPE_MODE (basetype);
3567 DECL_FIELD_IS_BASE (decl) = 1;
3569 /* Try to place the field. It may take more than one try if we
3570 have a hard time placing the field without putting two
3571 objects of the same type at the same address. */
3572 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3573 /* Add the new FIELD_DECL to the list of fields for T. */
3574 TREE_CHAIN (decl) = *next_field;
3576 next_field = &TREE_CHAIN (decl);
3583 /* On some platforms (ARM), even empty classes will not be
3585 eoc = round_up (rli_size_unit_so_far (rli),
3586 CLASSTYPE_ALIGN_UNIT (basetype));
3587 atend = layout_empty_base (binfo, eoc, offsets);
3588 /* A nearly-empty class "has no proper base class that is empty,
3589 not morally virtual, and at an offset other than zero." */
3590 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3593 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3594 /* The check above (used in G++ 3.2) is insufficient because
3595 an empty class placed at offset zero might itself have an
3596 empty base at a nonzero offset. */
3597 else if (walk_subobject_offsets (basetype,
3598 empty_base_at_nonzero_offset_p,
3601 /*max_offset=*/NULL_TREE,
3604 if (abi_version_at_least (2))
3605 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3608 "class %qT will be considered nearly empty in a "
3609 "future version of GCC", t);
3613 /* We do not create a FIELD_DECL for empty base classes because
3614 it might overlap some other field. We want to be able to
3615 create CONSTRUCTORs for the class by iterating over the
3616 FIELD_DECLs, and the back end does not handle overlapping
3619 /* An empty virtual base causes a class to be non-empty
3620 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3621 here because that was already done when the virtual table
3622 pointer was created. */
3625 /* Record the offsets of BINFO and its base subobjects. */
3626 record_subobject_offsets (binfo,
3627 BINFO_OFFSET (binfo),
3629 /*is_data_member=*/false);
3634 /* Layout all of the non-virtual base classes. Record empty
3635 subobjects in OFFSETS. T is the most derived type. Return nonzero
3636 if the type cannot be nearly empty. The fields created
3637 corresponding to the base classes will be inserted at
3641 build_base_fields (record_layout_info rli,
3642 splay_tree offsets, tree *next_field)
3644 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3647 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3650 /* The primary base class is always allocated first. */
3651 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3652 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3653 offsets, next_field);
3655 /* Now allocate the rest of the bases. */
3656 for (i = 0; i < n_baseclasses; ++i)
3660 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3662 /* The primary base was already allocated above, so we don't
3663 need to allocate it again here. */
3664 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3667 /* Virtual bases are added at the end (a primary virtual base
3668 will have already been added). */
3669 if (BINFO_VIRTUAL_P (base_binfo))
3672 next_field = build_base_field (rli, base_binfo,
3673 offsets, next_field);
3677 /* Go through the TYPE_METHODS of T issuing any appropriate
3678 diagnostics, figuring out which methods override which other
3679 methods, and so forth. */
3682 check_methods (tree t)
3686 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3688 check_for_override (x, t);
3689 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3690 error ("initializer specified for non-virtual method %q+D", x);
3691 /* The name of the field is the original field name
3692 Save this in auxiliary field for later overloading. */
3693 if (DECL_VINDEX (x))
3695 TYPE_POLYMORPHIC_P (t) = 1;
3696 if (DECL_PURE_VIRTUAL_P (x))
3697 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3699 /* All user-declared destructors are non-trivial. */
3700 if (DECL_DESTRUCTOR_P (x))
3701 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3705 /* FN is a constructor or destructor. Clone the declaration to create
3706 a specialized in-charge or not-in-charge version, as indicated by
3710 build_clone (tree fn, tree name)
3715 /* Copy the function. */
3716 clone = copy_decl (fn);
3717 /* Remember where this function came from. */
3718 DECL_CLONED_FUNCTION (clone) = fn;
3719 DECL_ABSTRACT_ORIGIN (clone) = fn;
3720 /* Reset the function name. */
3721 DECL_NAME (clone) = name;
3722 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3723 /* There's no pending inline data for this function. */
3724 DECL_PENDING_INLINE_INFO (clone) = NULL;
3725 DECL_PENDING_INLINE_P (clone) = 0;
3726 /* And it hasn't yet been deferred. */
3727 DECL_DEFERRED_FN (clone) = 0;
3729 /* The base-class destructor is not virtual. */
3730 if (name == base_dtor_identifier)
3732 DECL_VIRTUAL_P (clone) = 0;
3733 if (TREE_CODE (clone) != TEMPLATE_DECL)
3734 DECL_VINDEX (clone) = NULL_TREE;
3737 /* If there was an in-charge parameter, drop it from the function
3739 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3745 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3746 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3747 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3748 /* Skip the `this' parameter. */
3749 parmtypes = TREE_CHAIN (parmtypes);
3750 /* Skip the in-charge parameter. */
3751 parmtypes = TREE_CHAIN (parmtypes);
3752 /* And the VTT parm, in a complete [cd]tor. */
3753 if (DECL_HAS_VTT_PARM_P (fn)
3754 && ! DECL_NEEDS_VTT_PARM_P (clone))
3755 parmtypes = TREE_CHAIN (parmtypes);
3756 /* If this is subobject constructor or destructor, add the vtt
3759 = build_method_type_directly (basetype,
3760 TREE_TYPE (TREE_TYPE (clone)),
3763 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3766 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3767 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3770 /* Copy the function parameters. But, DECL_ARGUMENTS on a TEMPLATE_DECL
3771 aren't function parameters; those are the template parameters. */
3772 if (TREE_CODE (clone) != TEMPLATE_DECL)
3774 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3775 /* Remove the in-charge parameter. */
3776 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3778 TREE_CHAIN (DECL_ARGUMENTS (clone))
3779 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3780 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3782 /* And the VTT parm, in a complete [cd]tor. */
3783 if (DECL_HAS_VTT_PARM_P (fn))
3785 if (DECL_NEEDS_VTT_PARM_P (clone))
3786 DECL_HAS_VTT_PARM_P (clone) = 1;
3789 TREE_CHAIN (DECL_ARGUMENTS (clone))
3790 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3791 DECL_HAS_VTT_PARM_P (clone) = 0;
3795 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3797 DECL_CONTEXT (parms) = clone;
3798 cxx_dup_lang_specific_decl (parms);
3802 /* Create the RTL for this function. */
3803 SET_DECL_RTL (clone, NULL_RTX);
3804 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3806 /* Make it easy to find the CLONE given the FN. */
3807 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3808 TREE_CHAIN (fn) = clone;
3810 /* If this is a template, handle the DECL_TEMPLATE_RESULT as well. */
3811 if (TREE_CODE (clone) == TEMPLATE_DECL)
3815 DECL_TEMPLATE_RESULT (clone)
3816 = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3817 result = DECL_TEMPLATE_RESULT (clone);
3818 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3819 DECL_TI_TEMPLATE (result) = clone;
3822 note_decl_for_pch (clone);
3827 /* Produce declarations for all appropriate clones of FN. If
3828 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
3829 CLASTYPE_METHOD_VEC as well. */
3832 clone_function_decl (tree fn, int update_method_vec_p)
3836 /* Avoid inappropriate cloning. */
3838 && DECL_CLONED_FUNCTION (TREE_CHAIN (fn)))
3841 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
3843 /* For each constructor, we need two variants: an in-charge version
3844 and a not-in-charge version. */
3845 clone = build_clone (fn, complete_ctor_identifier);
3846 if (update_method_vec_p)
3847 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3848 clone = build_clone (fn, base_ctor_identifier);
3849 if (update_method_vec_p)
3850 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3854 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
3856 /* For each destructor, we need three variants: an in-charge
3857 version, a not-in-charge version, and an in-charge deleting
3858 version. We clone the deleting version first because that
3859 means it will go second on the TYPE_METHODS list -- and that
3860 corresponds to the correct layout order in the virtual
3863 For a non-virtual destructor, we do not build a deleting
3865 if (DECL_VIRTUAL_P (fn))
3867 clone = build_clone (fn, deleting_dtor_identifier);
3868 if (update_method_vec_p)
3869 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3871 clone = build_clone (fn, complete_dtor_identifier);
3872 if (update_method_vec_p)
3873 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3874 clone = build_clone (fn, base_dtor_identifier);
3875 if (update_method_vec_p)
3876 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3879 /* Note that this is an abstract function that is never emitted. */
3880 DECL_ABSTRACT (fn) = 1;
3883 /* DECL is an in charge constructor, which is being defined. This will
3884 have had an in class declaration, from whence clones were
3885 declared. An out-of-class definition can specify additional default
3886 arguments. As it is the clones that are involved in overload
3887 resolution, we must propagate the information from the DECL to its
3891 adjust_clone_args (tree decl)
3895 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION (clone);
3896 clone = TREE_CHAIN (clone))
3898 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
3899 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
3900 tree decl_parms, clone_parms;
3902 clone_parms = orig_clone_parms;
3904 /* Skip the 'this' parameter. */
3905 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
3906 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3908 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
3909 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3910 if (DECL_HAS_VTT_PARM_P (decl))
3911 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3913 clone_parms = orig_clone_parms;
3914 if (DECL_HAS_VTT_PARM_P (clone))
3915 clone_parms = TREE_CHAIN (clone_parms);
3917 for (decl_parms = orig_decl_parms; decl_parms;
3918 decl_parms = TREE_CHAIN (decl_parms),
3919 clone_parms = TREE_CHAIN (clone_parms))
3921 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
3922 TREE_TYPE (clone_parms)));
3924 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
3926 /* A default parameter has been added. Adjust the
3927 clone's parameters. */
3928 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3929 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3932 clone_parms = orig_decl_parms;
3934 if (DECL_HAS_VTT_PARM_P (clone))
3936 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
3937 TREE_VALUE (orig_clone_parms),
3939 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
3941 type = build_method_type_directly (basetype,
3942 TREE_TYPE (TREE_TYPE (clone)),
3945 type = build_exception_variant (type, exceptions);
3946 TREE_TYPE (clone) = type;
3948 clone_parms = NULL_TREE;
3952 gcc_assert (!clone_parms);
3956 /* For each of the constructors and destructors in T, create an
3957 in-charge and not-in-charge variant. */
3960 clone_constructors_and_destructors (tree t)
3964 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
3966 if (!CLASSTYPE_METHOD_VEC (t))
3969 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
3970 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
3971 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
3972 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
3975 /* Remove all zero-width bit-fields from T. */
3978 remove_zero_width_bit_fields (tree t)
3982 fieldsp = &TYPE_FIELDS (t);
3985 if (TREE_CODE (*fieldsp) == FIELD_DECL
3986 && DECL_C_BIT_FIELD (*fieldsp)
3987 && DECL_INITIAL (*fieldsp))
3988 *fieldsp = TREE_CHAIN (*fieldsp);
3990 fieldsp = &TREE_CHAIN (*fieldsp);
3994 /* Returns TRUE iff we need a cookie when dynamically allocating an
3995 array whose elements have the indicated class TYPE. */
3998 type_requires_array_cookie (tree type)
4001 bool has_two_argument_delete_p = false;
4003 gcc_assert (CLASS_TYPE_P (type));
4005 /* If there's a non-trivial destructor, we need a cookie. In order
4006 to iterate through the array calling the destructor for each
4007 element, we'll have to know how many elements there are. */
4008 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4011 /* If the usual deallocation function is a two-argument whose second
4012 argument is of type `size_t', then we have to pass the size of
4013 the array to the deallocation function, so we will need to store
4015 fns = lookup_fnfields (TYPE_BINFO (type),
4016 ansi_opname (VEC_DELETE_EXPR),
4018 /* If there are no `operator []' members, or the lookup is
4019 ambiguous, then we don't need a cookie. */
4020 if (!fns || fns == error_mark_node)
4022 /* Loop through all of the functions. */
4023 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4028 /* Select the current function. */
4029 fn = OVL_CURRENT (fns);
4030 /* See if this function is a one-argument delete function. If
4031 it is, then it will be the usual deallocation function. */
4032 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4033 if (second_parm == void_list_node)
4035 /* Otherwise, if we have a two-argument function and the second
4036 argument is `size_t', it will be the usual deallocation
4037 function -- unless there is one-argument function, too. */
4038 if (TREE_CHAIN (second_parm) == void_list_node
4039 && same_type_p (TREE_VALUE (second_parm), sizetype))
4040 has_two_argument_delete_p = true;
4043 return has_two_argument_delete_p;
4046 /* Check the validity of the bases and members declared in T. Add any
4047 implicitly-generated functions (like copy-constructors and
4048 assignment operators). Compute various flag bits (like
4049 CLASSTYPE_NON_POD_T) for T. This routine works purely at the C++
4050 level: i.e., independently of the ABI in use. */
4053 check_bases_and_members (tree t)
4055 /* Nonzero if the implicitly generated copy constructor should take
4056 a non-const reference argument. */
4057 int cant_have_const_ctor;
4058 /* Nonzero if the implicitly generated assignment operator
4059 should take a non-const reference argument. */
4060 int no_const_asn_ref;
4063 /* By default, we use const reference arguments and generate default
4065 cant_have_const_ctor = 0;
4066 no_const_asn_ref = 0;
4068 /* Check all the base-classes. */
4069 check_bases (t, &cant_have_const_ctor,
4072 /* Check all the method declarations. */
4075 /* Check all the data member declarations. We cannot call
4076 check_field_decls until we have called check_bases check_methods,
4077 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4078 being set appropriately. */
4079 check_field_decls (t, &access_decls,
4080 &cant_have_const_ctor,
4083 /* A nearly-empty class has to be vptr-containing; a nearly empty
4084 class contains just a vptr. */
4085 if (!TYPE_CONTAINS_VPTR_P (t))
4086 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4088 /* Do some bookkeeping that will guide the generation of implicitly
4089 declared member functions. */
4090 TYPE_HAS_COMPLEX_INIT_REF (t)
4091 |= (TYPE_HAS_INIT_REF (t) || TYPE_CONTAINS_VPTR_P (t));
4092 TYPE_NEEDS_CONSTRUCTING (t)
4093 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_CONTAINS_VPTR_P (t));
4094 CLASSTYPE_NON_AGGREGATE (t)
4095 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_POLYMORPHIC_P (t));
4096 CLASSTYPE_NON_POD_P (t)
4097 |= (CLASSTYPE_NON_AGGREGATE (t)
4098 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
4099 || TYPE_HAS_ASSIGN_REF (t));
4100 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
4101 |= TYPE_HAS_ASSIGN_REF (t) || TYPE_CONTAINS_VPTR_P (t);
4103 /* Synthesize any needed methods. */
4104 add_implicitly_declared_members (t,
4105 cant_have_const_ctor,
4108 /* Create the in-charge and not-in-charge variants of constructors
4110 clone_constructors_and_destructors (t);
4112 /* Process the using-declarations. */
4113 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4114 handle_using_decl (TREE_VALUE (access_decls), t);
4116 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4117 finish_struct_methods (t);
4119 /* Figure out whether or not we will need a cookie when dynamically
4120 allocating an array of this type. */
4121 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4122 = type_requires_array_cookie (t);
4125 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4126 accordingly. If a new vfield was created (because T doesn't have a
4127 primary base class), then the newly created field is returned. It
4128 is not added to the TYPE_FIELDS list; it is the caller's
4129 responsibility to do that. Accumulate declared virtual functions
4133 create_vtable_ptr (tree t, tree* virtuals_p)
4137 /* Collect the virtual functions declared in T. */
4138 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4139 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4140 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4142 tree new_virtual = make_node (TREE_LIST);
4144 BV_FN (new_virtual) = fn;
4145 BV_DELTA (new_virtual) = integer_zero_node;
4146 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4148 TREE_CHAIN (new_virtual) = *virtuals_p;
4149 *virtuals_p = new_virtual;
4152 /* If we couldn't find an appropriate base class, create a new field
4153 here. Even if there weren't any new virtual functions, we might need a
4154 new virtual function table if we're supposed to include vptrs in
4155 all classes that need them. */
4156 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4158 /* We build this decl with vtbl_ptr_type_node, which is a
4159 `vtable_entry_type*'. It might seem more precise to use
4160 `vtable_entry_type (*)[N]' where N is the number of virtual
4161 functions. However, that would require the vtable pointer in
4162 base classes to have a different type than the vtable pointer
4163 in derived classes. We could make that happen, but that
4164 still wouldn't solve all the problems. In particular, the
4165 type-based alias analysis code would decide that assignments
4166 to the base class vtable pointer can't alias assignments to
4167 the derived class vtable pointer, since they have different
4168 types. Thus, in a derived class destructor, where the base
4169 class constructor was inlined, we could generate bad code for
4170 setting up the vtable pointer.
4172 Therefore, we use one type for all vtable pointers. We still
4173 use a type-correct type; it's just doesn't indicate the array
4174 bounds. That's better than using `void*' or some such; it's
4175 cleaner, and it let's the alias analysis code know that these
4176 stores cannot alias stores to void*! */
4179 field = build_decl (FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4180 DECL_VIRTUAL_P (field) = 1;
4181 DECL_ARTIFICIAL (field) = 1;
4182 DECL_FIELD_CONTEXT (field) = t;
4183 DECL_FCONTEXT (field) = t;
4185 TYPE_VFIELD (t) = field;
4187 /* This class is non-empty. */
4188 CLASSTYPE_EMPTY_P (t) = 0;
4196 /* Fixup the inline function given by INFO now that the class is
4200 fixup_pending_inline (tree fn)
4202 if (DECL_PENDING_INLINE_INFO (fn))
4204 tree args = DECL_ARGUMENTS (fn);
4207 DECL_CONTEXT (args) = fn;
4208 args = TREE_CHAIN (args);
4213 /* Fixup the inline methods and friends in TYPE now that TYPE is
4217 fixup_inline_methods (tree type)
4219 tree method = TYPE_METHODS (type);
4220 VEC(tree,gc) *friends;
4223 if (method && TREE_CODE (method) == TREE_VEC)
4225 if (TREE_VEC_ELT (method, 1))
4226 method = TREE_VEC_ELT (method, 1);
4227 else if (TREE_VEC_ELT (method, 0))
4228 method = TREE_VEC_ELT (method, 0);
4230 method = TREE_VEC_ELT (method, 2);
4233 /* Do inline member functions. */
4234 for (; method; method = TREE_CHAIN (method))
4235 fixup_pending_inline (method);
4238 for (friends = CLASSTYPE_INLINE_FRIENDS (type), ix = 0;
4239 VEC_iterate (tree, friends, ix, method); ix++)
4240 fixup_pending_inline (method);
4241 CLASSTYPE_INLINE_FRIENDS (type) = NULL;
4244 /* Add OFFSET to all base types of BINFO which is a base in the
4245 hierarchy dominated by T.
4247 OFFSET, which is a type offset, is number of bytes. */
4250 propagate_binfo_offsets (tree binfo, tree offset)
4256 /* Update BINFO's offset. */
4257 BINFO_OFFSET (binfo)
4258 = convert (sizetype,
4259 size_binop (PLUS_EXPR,
4260 convert (ssizetype, BINFO_OFFSET (binfo)),
4263 /* Find the primary base class. */
4264 primary_binfo = get_primary_binfo (binfo);
4266 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4267 propagate_binfo_offsets (primary_binfo, offset);
4269 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4271 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4273 /* Don't do the primary base twice. */
4274 if (base_binfo == primary_binfo)
4277 if (BINFO_VIRTUAL_P (base_binfo))
4280 propagate_binfo_offsets (base_binfo, offset);
4284 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4285 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4286 empty subobjects of T. */
4289 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4293 bool first_vbase = true;
4296 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4299 if (!abi_version_at_least(2))
4301 /* In G++ 3.2, we incorrectly rounded the size before laying out
4302 the virtual bases. */
4303 finish_record_layout (rli, /*free_p=*/false);
4304 #ifdef STRUCTURE_SIZE_BOUNDARY
4305 /* Packed structures don't need to have minimum size. */
4306 if (! TYPE_PACKED (t))
4307 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4309 rli->offset = TYPE_SIZE_UNIT (t);
4310 rli->bitpos = bitsize_zero_node;
4311 rli->record_align = TYPE_ALIGN (t);
4314 /* Find the last field. The artificial fields created for virtual
4315 bases will go after the last extant field to date. */
4316 next_field = &TYPE_FIELDS (t);
4318 next_field = &TREE_CHAIN (*next_field);
4320 /* Go through the virtual bases, allocating space for each virtual
4321 base that is not already a primary base class. These are
4322 allocated in inheritance graph order. */
4323 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4325 if (!BINFO_VIRTUAL_P (vbase))
4328 if (!BINFO_PRIMARY_P (vbase))
4330 tree basetype = TREE_TYPE (vbase);
4332 /* This virtual base is not a primary base of any class in the
4333 hierarchy, so we have to add space for it. */
4334 next_field = build_base_field (rli, vbase,
4335 offsets, next_field);
4337 /* If the first virtual base might have been placed at a
4338 lower address, had we started from CLASSTYPE_SIZE, rather
4339 than TYPE_SIZE, issue a warning. There can be both false
4340 positives and false negatives from this warning in rare
4341 cases; to deal with all the possibilities would probably
4342 require performing both layout algorithms and comparing
4343 the results which is not particularly tractable. */
4347 (size_binop (CEIL_DIV_EXPR,
4348 round_up (CLASSTYPE_SIZE (t),
4349 CLASSTYPE_ALIGN (basetype)),
4351 BINFO_OFFSET (vbase))))
4353 "offset of virtual base %qT is not ABI-compliant and "
4354 "may change in a future version of GCC",
4357 first_vbase = false;
4362 /* Returns the offset of the byte just past the end of the base class
4366 end_of_base (tree binfo)
4370 if (is_empty_class (BINFO_TYPE (binfo)))
4371 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4372 allocate some space for it. It cannot have virtual bases, so
4373 TYPE_SIZE_UNIT is fine. */
4374 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4376 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4378 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4381 /* Returns the offset of the byte just past the end of the base class
4382 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4383 only non-virtual bases are included. */
4386 end_of_class (tree t, int include_virtuals_p)
4388 tree result = size_zero_node;
4389 VEC(tree,gc) *vbases;
4395 for (binfo = TYPE_BINFO (t), i = 0;
4396 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4398 if (!include_virtuals_p
4399 && BINFO_VIRTUAL_P (base_binfo)
4400 && (!BINFO_PRIMARY_P (base_binfo)
4401 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4404 offset = end_of_base (base_binfo);
4405 if (INT_CST_LT_UNSIGNED (result, offset))
4409 /* G++ 3.2 did not check indirect virtual bases. */
4410 if (abi_version_at_least (2) && include_virtuals_p)
4411 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4412 VEC_iterate (tree, vbases, i, base_binfo); i++)
4414 offset = end_of_base (base_binfo);
4415 if (INT_CST_LT_UNSIGNED (result, offset))
4422 /* Warn about bases of T that are inaccessible because they are
4423 ambiguous. For example:
4426 struct T : public S {};
4427 struct U : public S, public T {};
4429 Here, `(S*) new U' is not allowed because there are two `S'
4433 warn_about_ambiguous_bases (tree t)
4436 VEC(tree,gc) *vbases;
4441 /* If there are no repeated bases, nothing can be ambiguous. */
4442 if (!CLASSTYPE_REPEATED_BASE_P (t))
4445 /* Check direct bases. */
4446 for (binfo = TYPE_BINFO (t), i = 0;
4447 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4449 basetype = BINFO_TYPE (base_binfo);
4451 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4452 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4456 /* Check for ambiguous virtual bases. */
4458 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4459 VEC_iterate (tree, vbases, i, binfo); i++)
4461 basetype = BINFO_TYPE (binfo);
4463 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4464 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4469 /* Compare two INTEGER_CSTs K1 and K2. */
4472 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4474 return tree_int_cst_compare ((tree) k1, (tree) k2);
4477 /* Increase the size indicated in RLI to account for empty classes
4478 that are "off the end" of the class. */
4481 include_empty_classes (record_layout_info rli)
4486 /* It might be the case that we grew the class to allocate a
4487 zero-sized base class. That won't be reflected in RLI, yet,
4488 because we are willing to overlay multiple bases at the same
4489 offset. However, now we need to make sure that RLI is big enough
4490 to reflect the entire class. */
4491 eoc = end_of_class (rli->t,
4492 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4493 rli_size = rli_size_unit_so_far (rli);
4494 if (TREE_CODE (rli_size) == INTEGER_CST
4495 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4497 if (!abi_version_at_least (2))
4498 /* In version 1 of the ABI, the size of a class that ends with
4499 a bitfield was not rounded up to a whole multiple of a
4500 byte. Because rli_size_unit_so_far returns only the number
4501 of fully allocated bytes, any extra bits were not included
4503 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4505 /* The size should have been rounded to a whole byte. */
4506 gcc_assert (tree_int_cst_equal
4507 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4509 = size_binop (PLUS_EXPR,
4511 size_binop (MULT_EXPR,
4512 convert (bitsizetype,
4513 size_binop (MINUS_EXPR,
4515 bitsize_int (BITS_PER_UNIT)));
4516 normalize_rli (rli);
4520 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4521 BINFO_OFFSETs for all of the base-classes. Position the vtable
4522 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4525 layout_class_type (tree t, tree *virtuals_p)
4527 tree non_static_data_members;
4530 record_layout_info rli;
4531 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4532 types that appear at that offset. */
4533 splay_tree empty_base_offsets;
4534 /* True if the last field layed out was a bit-field. */
4535 bool last_field_was_bitfield = false;
4536 /* The location at which the next field should be inserted. */
4538 /* T, as a base class. */
4541 /* Keep track of the first non-static data member. */
4542 non_static_data_members = TYPE_FIELDS (t);
4544 /* Start laying out the record. */
4545 rli = start_record_layout (t);
4547 /* Mark all the primary bases in the hierarchy. */
4548 determine_primary_bases (t);
4550 /* Create a pointer to our virtual function table. */
4551 vptr = create_vtable_ptr (t, virtuals_p);
4553 /* The vptr is always the first thing in the class. */
4556 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4557 TYPE_FIELDS (t) = vptr;
4558 next_field = &TREE_CHAIN (vptr);
4559 place_field (rli, vptr);
4562 next_field = &TYPE_FIELDS (t);
4564 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4565 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4567 build_base_fields (rli, empty_base_offsets, next_field);
4569 /* Layout the non-static data members. */
4570 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4575 /* We still pass things that aren't non-static data members to
4576 the back-end, in case it wants to do something with them. */
4577 if (TREE_CODE (field) != FIELD_DECL)
4579 place_field (rli, field);
4580 /* If the static data member has incomplete type, keep track
4581 of it so that it can be completed later. (The handling
4582 of pending statics in finish_record_layout is
4583 insufficient; consider:
4586 struct S2 { static S1 s1; };
4588 At this point, finish_record_layout will be called, but
4589 S1 is still incomplete.) */
4590 if (TREE_CODE (field) == VAR_DECL)
4592 maybe_register_incomplete_var (field);
4593 /* The visibility of static data members is determined
4594 at their point of declaration, not their point of
4596 determine_visibility (field);
4601 type = TREE_TYPE (field);
4602 if (type == error_mark_node)
4605 padding = NULL_TREE;
4607 /* If this field is a bit-field whose width is greater than its
4608 type, then there are some special rules for allocating
4610 if (DECL_C_BIT_FIELD (field)
4611 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4613 integer_type_kind itk;
4615 bool was_unnamed_p = false;
4616 /* We must allocate the bits as if suitably aligned for the
4617 longest integer type that fits in this many bits. type
4618 of the field. Then, we are supposed to use the left over
4619 bits as additional padding. */
4620 for (itk = itk_char; itk != itk_none; ++itk)
4621 if (INT_CST_LT (DECL_SIZE (field),
4622 TYPE_SIZE (integer_types[itk])))
4625 /* ITK now indicates a type that is too large for the
4626 field. We have to back up by one to find the largest
4628 integer_type = integer_types[itk - 1];
4630 /* Figure out how much additional padding is required. GCC
4631 3.2 always created a padding field, even if it had zero
4633 if (!abi_version_at_least (2)
4634 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4636 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4637 /* In a union, the padding field must have the full width
4638 of the bit-field; all fields start at offset zero. */
4639 padding = DECL_SIZE (field);
4642 if (TREE_CODE (t) == UNION_TYPE)
4643 warning (OPT_Wabi, "size assigned to %qT may not be "
4644 "ABI-compliant and may change in a future "
4647 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4648 TYPE_SIZE (integer_type));
4651 #ifdef PCC_BITFIELD_TYPE_MATTERS
4652 /* An unnamed bitfield does not normally affect the
4653 alignment of the containing class on a target where
4654 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4655 make any exceptions for unnamed bitfields when the
4656 bitfields are longer than their types. Therefore, we
4657 temporarily give the field a name. */
4658 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4660 was_unnamed_p = true;
4661 DECL_NAME (field) = make_anon_name ();
4664 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4665 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4666 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4667 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4668 empty_base_offsets);
4670 DECL_NAME (field) = NULL_TREE;
4671 /* Now that layout has been performed, set the size of the
4672 field to the size of its declared type; the rest of the
4673 field is effectively invisible. */
4674 DECL_SIZE (field) = TYPE_SIZE (type);
4675 /* We must also reset the DECL_MODE of the field. */
4676 if (abi_version_at_least (2))
4677 DECL_MODE (field) = TYPE_MODE (type);
4679 && DECL_MODE (field) != TYPE_MODE (type))
4680 /* Versions of G++ before G++ 3.4 did not reset the
4683 "the offset of %qD may not be ABI-compliant and may "
4684 "change in a future version of GCC", field);
4687 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4688 empty_base_offsets);
4690 /* Remember the location of any empty classes in FIELD. */
4691 if (abi_version_at_least (2))
4692 record_subobject_offsets (TREE_TYPE (field),
4693 byte_position(field),
4695 /*is_data_member=*/true);
4697 /* If a bit-field does not immediately follow another bit-field,
4698 and yet it starts in the middle of a byte, we have failed to
4699 comply with the ABI. */
4701 && DECL_C_BIT_FIELD (field)
4702 /* The TREE_NO_WARNING flag gets set by Objective-C when
4703 laying out an Objective-C class. The ObjC ABI differs
4704 from the C++ ABI, and so we do not want a warning
4706 && !TREE_NO_WARNING (field)
4707 && !last_field_was_bitfield
4708 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
4709 DECL_FIELD_BIT_OFFSET (field),
4710 bitsize_unit_node)))
4711 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
4712 "change in a future version of GCC", field);
4714 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
4715 offset of the field. */
4717 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
4718 byte_position (field))
4719 && contains_empty_class_p (TREE_TYPE (field)))
4720 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
4721 "classes to be placed at different locations in a "
4722 "future version of GCC", field);
4724 /* The middle end uses the type of expressions to determine the
4725 possible range of expression values. In order to optimize
4726 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
4727 must be made aware of the width of "i", via its type.
4729 Because C++ does not have integer types of arbitrary width,
4730 we must (for the purposes of the front end) convert from the
4731 type assigned here to the declared type of the bitfield
4732 whenever a bitfield expression is used as an rvalue.
4733 Similarly, when assigning a value to a bitfield, the value
4734 must be converted to the type given the bitfield here. */
4735 if (DECL_C_BIT_FIELD (field))
4738 unsigned HOST_WIDE_INT width;
4739 ftype = TREE_TYPE (field);
4740 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
4741 if (width != TYPE_PRECISION (ftype))
4743 = c_build_bitfield_integer_type (width,
4744 TYPE_UNSIGNED (ftype));
4747 /* If we needed additional padding after this field, add it
4753 padding_field = build_decl (FIELD_DECL,
4756 DECL_BIT_FIELD (padding_field) = 1;
4757 DECL_SIZE (padding_field) = padding;
4758 DECL_CONTEXT (padding_field) = t;
4759 DECL_ARTIFICIAL (padding_field) = 1;
4760 DECL_IGNORED_P (padding_field) = 1;
4761 layout_nonempty_base_or_field (rli, padding_field,
4763 empty_base_offsets);
4766 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
4769 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
4771 /* Make sure that we are on a byte boundary so that the size of
4772 the class without virtual bases will always be a round number
4774 rli->bitpos = round_up (rli->bitpos, BITS_PER_UNIT);
4775 normalize_rli (rli);
4778 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
4780 if (!abi_version_at_least (2))
4781 include_empty_classes(rli);
4783 /* Delete all zero-width bit-fields from the list of fields. Now
4784 that the type is laid out they are no longer important. */
4785 remove_zero_width_bit_fields (t);
4787 /* Create the version of T used for virtual bases. We do not use
4788 make_aggr_type for this version; this is an artificial type. For
4789 a POD type, we just reuse T. */
4790 if (CLASSTYPE_NON_POD_P (t) || CLASSTYPE_EMPTY_P (t))
4792 base_t = make_node (TREE_CODE (t));
4794 /* Set the size and alignment for the new type. In G++ 3.2, all
4795 empty classes were considered to have size zero when used as
4797 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
4799 TYPE_SIZE (base_t) = bitsize_zero_node;
4800 TYPE_SIZE_UNIT (base_t) = size_zero_node;
4801 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
4803 "layout of classes derived from empty class %qT "
4804 "may change in a future version of GCC",
4811 /* If the ABI version is not at least two, and the last
4812 field was a bit-field, RLI may not be on a byte
4813 boundary. In particular, rli_size_unit_so_far might
4814 indicate the last complete byte, while rli_size_so_far
4815 indicates the total number of bits used. Therefore,
4816 rli_size_so_far, rather than rli_size_unit_so_far, is
4817 used to compute TYPE_SIZE_UNIT. */
4818 eoc = end_of_class (t, /*include_virtuals_p=*/0);
4819 TYPE_SIZE_UNIT (base_t)
4820 = size_binop (MAX_EXPR,
4822 size_binop (CEIL_DIV_EXPR,
4823 rli_size_so_far (rli),
4824 bitsize_int (BITS_PER_UNIT))),
4827 = size_binop (MAX_EXPR,
4828 rli_size_so_far (rli),
4829 size_binop (MULT_EXPR,
4830 convert (bitsizetype, eoc),
4831 bitsize_int (BITS_PER_UNIT)));
4833 TYPE_ALIGN (base_t) = rli->record_align;
4834 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
4836 /* Copy the fields from T. */
4837 next_field = &TYPE_FIELDS (base_t);
4838 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4839 if (TREE_CODE (field) == FIELD_DECL)
4841 *next_field = build_decl (FIELD_DECL,
4844 DECL_CONTEXT (*next_field) = base_t;
4845 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
4846 DECL_FIELD_BIT_OFFSET (*next_field)
4847 = DECL_FIELD_BIT_OFFSET (field);
4848 DECL_SIZE (*next_field) = DECL_SIZE (field);
4849 DECL_MODE (*next_field) = DECL_MODE (field);
4850 next_field = &TREE_CHAIN (*next_field);
4853 /* Record the base version of the type. */
4854 CLASSTYPE_AS_BASE (t) = base_t;
4855 TYPE_CONTEXT (base_t) = t;
4858 CLASSTYPE_AS_BASE (t) = t;
4860 /* Every empty class contains an empty class. */
4861 if (CLASSTYPE_EMPTY_P (t))
4862 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
4864 /* Set the TYPE_DECL for this type to contain the right
4865 value for DECL_OFFSET, so that we can use it as part
4866 of a COMPONENT_REF for multiple inheritance. */
4867 layout_decl (TYPE_MAIN_DECL (t), 0);
4869 /* Now fix up any virtual base class types that we left lying
4870 around. We must get these done before we try to lay out the
4871 virtual function table. As a side-effect, this will remove the
4872 base subobject fields. */
4873 layout_virtual_bases (rli, empty_base_offsets);
4875 /* Make sure that empty classes are reflected in RLI at this
4877 include_empty_classes(rli);
4879 /* Make sure not to create any structures with zero size. */
4880 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
4882 build_decl (FIELD_DECL, NULL_TREE, char_type_node));
4884 /* Let the back-end lay out the type. */
4885 finish_record_layout (rli, /*free_p=*/true);
4887 /* Warn about bases that can't be talked about due to ambiguity. */
4888 warn_about_ambiguous_bases (t);
4890 /* Now that we're done with layout, give the base fields the real types. */
4891 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4892 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
4893 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
4896 splay_tree_delete (empty_base_offsets);
4898 if (CLASSTYPE_EMPTY_P (t)
4899 && tree_int_cst_lt (sizeof_biggest_empty_class,
4900 TYPE_SIZE_UNIT (t)))
4901 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
4904 /* Determine the "key method" for the class type indicated by TYPE,
4905 and set CLASSTYPE_KEY_METHOD accordingly. */
4908 determine_key_method (tree type)
4912 if (TYPE_FOR_JAVA (type)
4913 || processing_template_decl
4914 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
4915 || CLASSTYPE_INTERFACE_KNOWN (type))
4918 /* The key method is the first non-pure virtual function that is not
4919 inline at the point of class definition. On some targets the
4920 key function may not be inline; those targets should not call
4921 this function until the end of the translation unit. */
4922 for (method = TYPE_METHODS (type); method != NULL_TREE;
4923 method = TREE_CHAIN (method))
4924 if (DECL_VINDEX (method) != NULL_TREE
4925 && ! DECL_DECLARED_INLINE_P (method)
4926 && ! DECL_PURE_VIRTUAL_P (method))
4928 CLASSTYPE_KEY_METHOD (type) = method;
4935 /* Perform processing required when the definition of T (a class type)
4939 finish_struct_1 (tree t)
4942 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
4943 tree virtuals = NULL_TREE;
4946 if (COMPLETE_TYPE_P (t))
4948 gcc_assert (IS_AGGR_TYPE (t));
4949 error ("redefinition of %q#T", t);
4954 /* If this type was previously laid out as a forward reference,
4955 make sure we lay it out again. */
4956 TYPE_SIZE (t) = NULL_TREE;
4957 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
4959 fixup_inline_methods (t);
4961 /* Make assumptions about the class; we'll reset the flags if
4963 CLASSTYPE_EMPTY_P (t) = 1;
4964 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
4965 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
4967 /* Do end-of-class semantic processing: checking the validity of the
4968 bases and members and add implicitly generated methods. */
4969 check_bases_and_members (t);
4971 /* Find the key method. */
4972 if (TYPE_CONTAINS_VPTR_P (t))
4974 /* The Itanium C++ ABI permits the key method to be chosen when
4975 the class is defined -- even though the key method so
4976 selected may later turn out to be an inline function. On
4977 some systems (such as ARM Symbian OS) the key method cannot
4978 be determined until the end of the translation unit. On such
4979 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
4980 will cause the class to be added to KEYED_CLASSES. Then, in
4981 finish_file we will determine the key method. */
4982 if (targetm.cxx.key_method_may_be_inline ())
4983 determine_key_method (t);
4985 /* If a polymorphic class has no key method, we may emit the vtable
4986 in every translation unit where the class definition appears. */
4987 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
4988 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
4991 /* Layout the class itself. */
4992 layout_class_type (t, &virtuals);
4993 if (CLASSTYPE_AS_BASE (t) != t)
4994 /* We use the base type for trivial assignments, and hence it
4996 compute_record_mode (CLASSTYPE_AS_BASE (t));
4998 virtuals = modify_all_vtables (t, nreverse (virtuals));
5000 /* If necessary, create the primary vtable for this class. */
5001 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5003 /* We must enter these virtuals into the table. */
5004 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5005 build_primary_vtable (NULL_TREE, t);
5006 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5007 /* Here we know enough to change the type of our virtual
5008 function table, but we will wait until later this function. */
5009 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5012 if (TYPE_CONTAINS_VPTR_P (t))
5017 if (BINFO_VTABLE (TYPE_BINFO (t)))
5018 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5019 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5020 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5022 /* Add entries for virtual functions introduced by this class. */
5023 BINFO_VIRTUALS (TYPE_BINFO (t))
5024 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5026 /* Set DECL_VINDEX for all functions declared in this class. */
5027 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5029 fn = TREE_CHAIN (fn),
5030 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5031 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5033 tree fndecl = BV_FN (fn);
5035 if (DECL_THUNK_P (fndecl))
5036 /* A thunk. We should never be calling this entry directly
5037 from this vtable -- we'd use the entry for the non
5038 thunk base function. */
5039 DECL_VINDEX (fndecl) = NULL_TREE;
5040 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5041 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5045 finish_struct_bits (t);
5047 /* Complete the rtl for any static member objects of the type we're
5049 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5050 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5051 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5052 DECL_MODE (x) = TYPE_MODE (t);
5054 /* Done with FIELDS...now decide whether to sort these for
5055 faster lookups later.
5057 We use a small number because most searches fail (succeeding
5058 ultimately as the search bores through the inheritance
5059 hierarchy), and we want this failure to occur quickly. */
5061 n_fields = count_fields (TYPE_FIELDS (t));
5064 struct sorted_fields_type *field_vec = GGC_NEWVAR
5065 (struct sorted_fields_type,
5066 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5067 field_vec->len = n_fields;
5068 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5069 qsort (field_vec->elts, n_fields, sizeof (tree),
5071 if (! DECL_LANG_SPECIFIC (TYPE_MAIN_DECL (t)))
5072 retrofit_lang_decl (TYPE_MAIN_DECL (t));
5073 DECL_SORTED_FIELDS (TYPE_MAIN_DECL (t)) = field_vec;
5076 /* Complain if one of the field types requires lower visibility. */
5077 constrain_class_visibility (t);
5079 /* Make the rtl for any new vtables we have created, and unmark
5080 the base types we marked. */
5083 /* Build the VTT for T. */
5086 /* This warning does not make sense for Java classes, since they
5087 cannot have destructors. */
5088 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5092 dtor = CLASSTYPE_DESTRUCTORS (t);
5093 /* Warn only if the dtor is non-private or the class has
5095 if (/* An implicitly declared destructor is always public. And,
5096 if it were virtual, we would have created it by now. */
5098 || (!DECL_VINDEX (dtor)
5099 && (!TREE_PRIVATE (dtor)
5100 || CLASSTYPE_FRIEND_CLASSES (t)
5101 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))
5102 warning (0, "%q#T has virtual functions but non-virtual destructor",
5108 if (warn_overloaded_virtual)
5111 /* Class layout, assignment of virtual table slots, etc., is now
5112 complete. Give the back end a chance to tweak the visibility of
5113 the class or perform any other required target modifications. */
5114 targetm.cxx.adjust_class_at_definition (t);
5116 maybe_suppress_debug_info (t);
5118 dump_class_hierarchy (t);
5120 /* Finish debugging output for this type. */
5121 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5124 /* When T was built up, the member declarations were added in reverse
5125 order. Rearrange them to declaration order. */
5128 unreverse_member_declarations (tree t)
5134 /* The following lists are all in reverse order. Put them in
5135 declaration order now. */
5136 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5137 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5139 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5140 reverse order, so we can't just use nreverse. */
5142 for (x = TYPE_FIELDS (t);
5143 x && TREE_CODE (x) != TYPE_DECL;
5146 next = TREE_CHAIN (x);
5147 TREE_CHAIN (x) = prev;
5152 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5154 TYPE_FIELDS (t) = prev;
5159 finish_struct (tree t, tree attributes)
5161 location_t saved_loc = input_location;
5163 /* Now that we've got all the field declarations, reverse everything
5165 unreverse_member_declarations (t);
5167 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5169 /* Nadger the current location so that diagnostics point to the start of
5170 the struct, not the end. */
5171 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5173 if (processing_template_decl)
5177 finish_struct_methods (t);
5178 TYPE_SIZE (t) = bitsize_zero_node;
5179 TYPE_SIZE_UNIT (t) = size_zero_node;
5181 /* We need to emit an error message if this type was used as a parameter
5182 and it is an abstract type, even if it is a template. We construct
5183 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5184 account and we call complete_vars with this type, which will check
5185 the PARM_DECLS. Note that while the type is being defined,
5186 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5187 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5188 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5189 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5190 if (DECL_PURE_VIRTUAL_P (x))
5191 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5195 finish_struct_1 (t);
5197 input_location = saved_loc;
5199 TYPE_BEING_DEFINED (t) = 0;
5201 if (current_class_type)
5204 error ("trying to finish struct, but kicked out due to previous parse errors");
5206 if (processing_template_decl && at_function_scope_p ())
5207 add_stmt (build_min (TAG_DEFN, t));
5212 /* Return the dynamic type of INSTANCE, if known.
5213 Used to determine whether the virtual function table is needed
5216 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5217 of our knowledge of its type. *NONNULL should be initialized
5218 before this function is called. */
5221 fixed_type_or_null (tree instance, int* nonnull, int* cdtorp)
5223 switch (TREE_CODE (instance))
5226 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5229 return fixed_type_or_null (TREE_OPERAND (instance, 0),
5233 /* This is a call to a constructor, hence it's never zero. */
5234 if (TREE_HAS_CONSTRUCTOR (instance))
5238 return TREE_TYPE (instance);
5243 /* This is a call to a constructor, hence it's never zero. */
5244 if (TREE_HAS_CONSTRUCTOR (instance))
5248 return TREE_TYPE (instance);
5250 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5254 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5255 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5256 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5257 /* Propagate nonnull. */
5258 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5263 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5266 instance = TREE_OPERAND (instance, 0);
5269 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5270 with a real object -- given &p->f, p can still be null. */
5271 tree t = get_base_address (instance);
5272 /* ??? Probably should check DECL_WEAK here. */
5273 if (t && DECL_P (t))
5276 return fixed_type_or_null (instance, nonnull, cdtorp);
5279 /* If this component is really a base class reference, then the field
5280 itself isn't definitive. */
5281 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5282 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5283 return fixed_type_or_null (TREE_OPERAND (instance, 1), nonnull, cdtorp);
5287 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5288 && IS_AGGR_TYPE (TREE_TYPE (TREE_TYPE (instance))))
5292 return TREE_TYPE (TREE_TYPE (instance));
5294 /* fall through... */
5298 if (IS_AGGR_TYPE (TREE_TYPE (instance)))
5302 return TREE_TYPE (instance);
5304 else if (instance == current_class_ptr)
5309 /* if we're in a ctor or dtor, we know our type. */
5310 if (DECL_LANG_SPECIFIC (current_function_decl)
5311 && (DECL_CONSTRUCTOR_P (current_function_decl)
5312 || DECL_DESTRUCTOR_P (current_function_decl)))
5316 return TREE_TYPE (TREE_TYPE (instance));
5319 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5321 /* Reference variables should be references to objects. */
5325 /* DECL_VAR_MARKED_P is used to prevent recursion; a
5326 variable's initializer may refer to the variable
5328 if (TREE_CODE (instance) == VAR_DECL
5329 && DECL_INITIAL (instance)
5330 && !DECL_VAR_MARKED_P (instance))
5333 DECL_VAR_MARKED_P (instance) = 1;
5334 type = fixed_type_or_null (DECL_INITIAL (instance),
5336 DECL_VAR_MARKED_P (instance) = 0;
5347 /* Return nonzero if the dynamic type of INSTANCE is known, and
5348 equivalent to the static type. We also handle the case where
5349 INSTANCE is really a pointer. Return negative if this is a
5350 ctor/dtor. There the dynamic type is known, but this might not be
5351 the most derived base of the original object, and hence virtual
5352 bases may not be layed out according to this type.
5354 Used to determine whether the virtual function table is needed
5357 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5358 of our knowledge of its type. *NONNULL should be initialized
5359 before this function is called. */
5362 resolves_to_fixed_type_p (tree instance, int* nonnull)
5364 tree t = TREE_TYPE (instance);
5367 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5368 if (fixed == NULL_TREE)
5370 if (POINTER_TYPE_P (t))
5372 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5374 return cdtorp ? -1 : 1;
5379 init_class_processing (void)
5381 current_class_depth = 0;
5382 current_class_stack_size = 10;
5384 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5385 local_classes = VEC_alloc (tree, gc, 8);
5386 sizeof_biggest_empty_class = size_zero_node;
5388 ridpointers[(int) RID_PUBLIC] = access_public_node;
5389 ridpointers[(int) RID_PRIVATE] = access_private_node;
5390 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5393 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5396 restore_class_cache (void)
5400 /* We are re-entering the same class we just left, so we don't
5401 have to search the whole inheritance matrix to find all the
5402 decls to bind again. Instead, we install the cached
5403 class_shadowed list and walk through it binding names. */
5404 push_binding_level (previous_class_level);
5405 class_binding_level = previous_class_level;
5406 /* Restore IDENTIFIER_TYPE_VALUE. */
5407 for (type = class_binding_level->type_shadowed;
5409 type = TREE_CHAIN (type))
5410 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5413 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5414 appropriate for TYPE.
5416 So that we may avoid calls to lookup_name, we cache the _TYPE
5417 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5419 For multiple inheritance, we perform a two-pass depth-first search
5420 of the type lattice. */
5423 pushclass (tree type)
5425 class_stack_node_t csn;
5427 type = TYPE_MAIN_VARIANT (type);
5429 /* Make sure there is enough room for the new entry on the stack. */
5430 if (current_class_depth + 1 >= current_class_stack_size)
5432 current_class_stack_size *= 2;
5434 = XRESIZEVEC (struct class_stack_node, current_class_stack,
5435 current_class_stack_size);
5438 /* Insert a new entry on the class stack. */
5439 csn = current_class_stack + current_class_depth;
5440 csn->name = current_class_name;
5441 csn->type = current_class_type;
5442 csn->access = current_access_specifier;
5443 csn->names_used = 0;
5445 current_class_depth++;
5447 /* Now set up the new type. */
5448 current_class_name = TYPE_NAME (type);
5449 if (TREE_CODE (current_class_name) == TYPE_DECL)
5450 current_class_name = DECL_NAME (current_class_name);
5451 current_class_type = type;
5453 /* By default, things in classes are private, while things in
5454 structures or unions are public. */
5455 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5456 ? access_private_node
5457 : access_public_node);
5459 if (previous_class_level
5460 && type != previous_class_level->this_entity
5461 && current_class_depth == 1)
5463 /* Forcibly remove any old class remnants. */
5464 invalidate_class_lookup_cache ();
5467 if (!previous_class_level
5468 || type != previous_class_level->this_entity
5469 || current_class_depth > 1)
5472 restore_class_cache ();
5475 /* When we exit a toplevel class scope, we save its binding level so
5476 that we can restore it quickly. Here, we've entered some other
5477 class, so we must invalidate our cache. */
5480 invalidate_class_lookup_cache (void)
5482 previous_class_level = NULL;
5485 /* Get out of the current class scope. If we were in a class scope
5486 previously, that is the one popped to. */
5493 current_class_depth--;
5494 current_class_name = current_class_stack[current_class_depth].name;
5495 current_class_type = current_class_stack[current_class_depth].type;
5496 current_access_specifier = current_class_stack[current_class_depth].access;
5497 if (current_class_stack[current_class_depth].names_used)
5498 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5501 /* Mark the top of the class stack as hidden. */
5504 push_class_stack (void)
5506 if (current_class_depth)
5507 ++current_class_stack[current_class_depth - 1].hidden;
5510 /* Mark the top of the class stack as un-hidden. */
5513 pop_class_stack (void)
5515 if (current_class_depth)
5516 --current_class_stack[current_class_depth - 1].hidden;
5519 /* Returns 1 if the class type currently being defined is either T or
5520 a nested type of T. */
5523 currently_open_class (tree t)
5527 /* We start looking from 1 because entry 0 is from global scope,
5529 for (i = current_class_depth; i > 0; --i)
5532 if (i == current_class_depth)
5533 c = current_class_type;
5536 if (current_class_stack[i].hidden)
5538 c = current_class_stack[i].type;
5542 if (same_type_p (c, t))
5548 /* If either current_class_type or one of its enclosing classes are derived
5549 from T, return the appropriate type. Used to determine how we found
5550 something via unqualified lookup. */
5553 currently_open_derived_class (tree t)
5557 /* The bases of a dependent type are unknown. */
5558 if (dependent_type_p (t))
5561 if (!current_class_type)
5564 if (DERIVED_FROM_P (t, current_class_type))
5565 return current_class_type;
5567 for (i = current_class_depth - 1; i > 0; --i)
5569 if (current_class_stack[i].hidden)
5571 if (DERIVED_FROM_P (t, current_class_stack[i].type))
5572 return current_class_stack[i].type;
5578 /* When entering a class scope, all enclosing class scopes' names with
5579 static meaning (static variables, static functions, types and
5580 enumerators) have to be visible. This recursive function calls
5581 pushclass for all enclosing class contexts until global or a local
5582 scope is reached. TYPE is the enclosed class. */
5585 push_nested_class (tree type)
5589 /* A namespace might be passed in error cases, like A::B:C. */
5590 if (type == NULL_TREE
5591 || type == error_mark_node
5592 || TREE_CODE (type) == NAMESPACE_DECL
5593 || ! IS_AGGR_TYPE (type)
5594 || TREE_CODE (type) == TEMPLATE_TYPE_PARM
5595 || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
5598 context = DECL_CONTEXT (TYPE_MAIN_DECL (type));
5600 if (context && CLASS_TYPE_P (context))
5601 push_nested_class (context);
5605 /* Undoes a push_nested_class call. */
5608 pop_nested_class (void)
5610 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5613 if (context && CLASS_TYPE_P (context))
5614 pop_nested_class ();
5617 /* Returns the number of extern "LANG" blocks we are nested within. */
5620 current_lang_depth (void)
5622 return VEC_length (tree, current_lang_base);
5625 /* Set global variables CURRENT_LANG_NAME to appropriate value
5626 so that behavior of name-mangling machinery is correct. */
5629 push_lang_context (tree name)
5631 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
5633 if (name == lang_name_cplusplus)
5635 current_lang_name = name;
5637 else if (name == lang_name_java)
5639 current_lang_name = name;
5640 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5641 (See record_builtin_java_type in decl.c.) However, that causes
5642 incorrect debug entries if these types are actually used.
5643 So we re-enable debug output after extern "Java". */
5644 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
5645 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
5646 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
5647 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
5648 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
5649 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
5650 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
5651 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
5653 else if (name == lang_name_c)
5655 current_lang_name = name;
5658 error ("language string %<\"%E\"%> not recognized", name);
5661 /* Get out of the current language scope. */
5664 pop_lang_context (void)
5666 current_lang_name = VEC_pop (tree, current_lang_base);
5669 /* Type instantiation routines. */
5671 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
5672 matches the TARGET_TYPE. If there is no satisfactory match, return
5673 error_mark_node, and issue an error & warning messages under
5674 control of FLAGS. Permit pointers to member function if FLAGS
5675 permits. If TEMPLATE_ONLY, the name of the overloaded function was
5676 a template-id, and EXPLICIT_TARGS are the explicitly provided
5677 template arguments. If OVERLOAD is for one or more member
5678 functions, then ACCESS_PATH is the base path used to reference
5679 those member functions. */
5682 resolve_address_of_overloaded_function (tree target_type,
5684 tsubst_flags_t flags,
5686 tree explicit_targs,
5689 /* Here's what the standard says:
5693 If the name is a function template, template argument deduction
5694 is done, and if the argument deduction succeeds, the deduced
5695 arguments are used to generate a single template function, which
5696 is added to the set of overloaded functions considered.
5698 Non-member functions and static member functions match targets of
5699 type "pointer-to-function" or "reference-to-function." Nonstatic
5700 member functions match targets of type "pointer-to-member
5701 function;" the function type of the pointer to member is used to
5702 select the member function from the set of overloaded member
5703 functions. If a nonstatic member function is selected, the
5704 reference to the overloaded function name is required to have the
5705 form of a pointer to member as described in 5.3.1.
5707 If more than one function is selected, any template functions in
5708 the set are eliminated if the set also contains a non-template
5709 function, and any given template function is eliminated if the
5710 set contains a second template function that is more specialized
5711 than the first according to the partial ordering rules 14.5.5.2.
5712 After such eliminations, if any, there shall remain exactly one
5713 selected function. */
5716 int is_reference = 0;
5717 /* We store the matches in a TREE_LIST rooted here. The functions
5718 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
5719 interoperability with most_specialized_instantiation. */
5720 tree matches = NULL_TREE;
5723 /* By the time we get here, we should be seeing only real
5724 pointer-to-member types, not the internal POINTER_TYPE to
5725 METHOD_TYPE representation. */
5726 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
5727 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
5729 gcc_assert (is_overloaded_fn (overload));
5731 /* Check that the TARGET_TYPE is reasonable. */
5732 if (TYPE_PTRFN_P (target_type))
5734 else if (TYPE_PTRMEMFUNC_P (target_type))
5735 /* This is OK, too. */
5737 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
5739 /* This is OK, too. This comes from a conversion to reference
5741 target_type = build_reference_type (target_type);
5746 if (flags & tf_error)
5747 error ("cannot resolve overloaded function %qD based on"
5748 " conversion to type %qT",
5749 DECL_NAME (OVL_FUNCTION (overload)), target_type);
5750 return error_mark_node;
5753 /* If we can find a non-template function that matches, we can just
5754 use it. There's no point in generating template instantiations
5755 if we're just going to throw them out anyhow. But, of course, we
5756 can only do this when we don't *need* a template function. */
5761 for (fns = overload; fns; fns = OVL_NEXT (fns))
5763 tree fn = OVL_CURRENT (fns);
5766 if (TREE_CODE (fn) == TEMPLATE_DECL)
5767 /* We're not looking for templates just yet. */
5770 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5772 /* We're looking for a non-static member, and this isn't
5773 one, or vice versa. */
5776 /* Ignore functions which haven't been explicitly
5778 if (DECL_ANTICIPATED (fn))
5781 /* See if there's a match. */
5782 fntype = TREE_TYPE (fn);
5784 fntype = build_ptrmemfunc_type (build_pointer_type (fntype));
5785 else if (!is_reference)
5786 fntype = build_pointer_type (fntype);
5788 if (can_convert_arg (target_type, fntype, fn, LOOKUP_NORMAL))
5789 matches = tree_cons (fn, NULL_TREE, matches);
5793 /* Now, if we've already got a match (or matches), there's no need
5794 to proceed to the template functions. But, if we don't have a
5795 match we need to look at them, too. */
5798 tree target_fn_type;
5799 tree target_arg_types;
5800 tree target_ret_type;
5805 = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (target_type));
5807 target_fn_type = TREE_TYPE (target_type);
5808 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
5809 target_ret_type = TREE_TYPE (target_fn_type);
5811 /* Never do unification on the 'this' parameter. */
5812 if (TREE_CODE (target_fn_type) == METHOD_TYPE)
5813 target_arg_types = TREE_CHAIN (target_arg_types);
5815 for (fns = overload; fns; fns = OVL_NEXT (fns))
5817 tree fn = OVL_CURRENT (fns);
5819 tree instantiation_type;
5822 if (TREE_CODE (fn) != TEMPLATE_DECL)
5823 /* We're only looking for templates. */
5826 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5828 /* We're not looking for a non-static member, and this is
5829 one, or vice versa. */
5832 /* Try to do argument deduction. */
5833 targs = make_tree_vec (DECL_NTPARMS (fn));
5834 if (fn_type_unification (fn, explicit_targs, targs,
5835 target_arg_types, target_ret_type,
5836 DEDUCE_EXACT, LOOKUP_NORMAL))
5837 /* Argument deduction failed. */
5840 /* Instantiate the template. */
5841 instantiation = instantiate_template (fn, targs, flags);
5842 if (instantiation == error_mark_node)
5843 /* Instantiation failed. */
5846 /* See if there's a match. */
5847 instantiation_type = TREE_TYPE (instantiation);
5849 instantiation_type =
5850 build_ptrmemfunc_type (build_pointer_type (instantiation_type));
5851 else if (!is_reference)
5852 instantiation_type = build_pointer_type (instantiation_type);
5853 if (can_convert_arg (target_type, instantiation_type, instantiation,
5855 matches = tree_cons (instantiation, fn, matches);
5858 /* Now, remove all but the most specialized of the matches. */
5861 tree match = most_specialized_instantiation (matches);
5863 if (match != error_mark_node)
5864 matches = tree_cons (TREE_PURPOSE (match),
5870 /* Now we should have exactly one function in MATCHES. */
5871 if (matches == NULL_TREE)
5873 /* There were *no* matches. */
5874 if (flags & tf_error)
5876 error ("no matches converting function %qD to type %q#T",
5877 DECL_NAME (OVL_FUNCTION (overload)),
5880 /* print_candidates expects a chain with the functions in
5881 TREE_VALUE slots, so we cons one up here (we're losing anyway,
5882 so why be clever?). */
5883 for (; overload; overload = OVL_NEXT (overload))
5884 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
5887 print_candidates (matches);
5889 return error_mark_node;
5891 else if (TREE_CHAIN (matches))
5893 /* There were too many matches. */
5895 if (flags & tf_error)
5899 error ("converting overloaded function %qD to type %q#T is ambiguous",
5900 DECL_NAME (OVL_FUNCTION (overload)),
5903 /* Since print_candidates expects the functions in the
5904 TREE_VALUE slot, we flip them here. */
5905 for (match = matches; match; match = TREE_CHAIN (match))
5906 TREE_VALUE (match) = TREE_PURPOSE (match);
5908 print_candidates (matches);
5911 return error_mark_node;
5914 /* Good, exactly one match. Now, convert it to the correct type. */
5915 fn = TREE_PURPOSE (matches);
5917 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
5918 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
5920 static int explained;
5922 if (!(flags & tf_error))
5923 return error_mark_node;
5925 pedwarn ("assuming pointer to member %qD", fn);
5928 pedwarn ("(a pointer to member can only be formed with %<&%E%>)", fn);
5933 /* If we're doing overload resolution purely for the purpose of
5934 determining conversion sequences, we should not consider the
5935 function used. If this conversion sequence is selected, the
5936 function will be marked as used at this point. */
5937 if (!(flags & tf_conv))
5940 /* We could not check access when this expression was originally
5941 created since we did not know at that time to which function
5942 the expression referred. */
5943 if (DECL_FUNCTION_MEMBER_P (fn))
5945 gcc_assert (access_path);
5946 perform_or_defer_access_check (access_path, fn);
5950 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
5951 return build_unary_op (ADDR_EXPR, fn, 0);
5954 /* The target must be a REFERENCE_TYPE. Above, build_unary_op
5955 will mark the function as addressed, but here we must do it
5957 cxx_mark_addressable (fn);
5963 /* This function will instantiate the type of the expression given in
5964 RHS to match the type of LHSTYPE. If errors exist, then return
5965 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
5966 we complain on errors. If we are not complaining, never modify rhs,
5967 as overload resolution wants to try many possible instantiations, in
5968 the hope that at least one will work.
5970 For non-recursive calls, LHSTYPE should be a function, pointer to
5971 function, or a pointer to member function. */
5974 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
5976 tsubst_flags_t flags_in = flags;
5977 tree access_path = NULL_TREE;
5979 flags &= ~tf_ptrmem_ok;
5981 if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
5983 if (flags & tf_error)
5984 error ("not enough type information");
5985 return error_mark_node;
5988 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
5990 if (same_type_p (lhstype, TREE_TYPE (rhs)))
5992 if (flag_ms_extensions
5993 && TYPE_PTRMEMFUNC_P (lhstype)
5994 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
5995 /* Microsoft allows `A::f' to be resolved to a
5996 pointer-to-member. */
6000 if (flags & tf_error)
6001 error ("argument of type %qT does not match %qT",
6002 TREE_TYPE (rhs), lhstype);
6003 return error_mark_node;
6007 if (TREE_CODE (rhs) == BASELINK)
6009 access_path = BASELINK_ACCESS_BINFO (rhs);
6010 rhs = BASELINK_FUNCTIONS (rhs);
6013 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6014 deduce any type information. */
6015 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6017 if (flags & tf_error)
6018 error ("not enough type information");
6019 return error_mark_node;
6022 /* There only a few kinds of expressions that may have a type
6023 dependent on overload resolution. */
6024 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6025 || TREE_CODE (rhs) == COMPONENT_REF
6026 || TREE_CODE (rhs) == COMPOUND_EXPR
6027 || really_overloaded_fn (rhs));
6029 /* We don't overwrite rhs if it is an overloaded function.
6030 Copying it would destroy the tree link. */
6031 if (TREE_CODE (rhs) != OVERLOAD)
6032 rhs = copy_node (rhs);
6034 /* This should really only be used when attempting to distinguish
6035 what sort of a pointer to function we have. For now, any
6036 arithmetic operation which is not supported on pointers
6037 is rejected as an error. */
6039 switch (TREE_CODE (rhs))
6043 tree member = TREE_OPERAND (rhs, 1);
6045 member = instantiate_type (lhstype, member, flags);
6046 if (member != error_mark_node
6047 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6048 /* Do not lose object's side effects. */
6049 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6050 TREE_OPERAND (rhs, 0), member);
6055 rhs = TREE_OPERAND (rhs, 1);
6056 if (BASELINK_P (rhs))
6057 return instantiate_type (lhstype, rhs, flags_in);
6059 /* This can happen if we are forming a pointer-to-member for a
6061 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6065 case TEMPLATE_ID_EXPR:
6067 tree fns = TREE_OPERAND (rhs, 0);
6068 tree args = TREE_OPERAND (rhs, 1);
6071 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6072 /*template_only=*/true,
6079 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6080 /*template_only=*/false,
6081 /*explicit_targs=*/NULL_TREE,
6085 TREE_OPERAND (rhs, 0)
6086 = instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6087 if (TREE_OPERAND (rhs, 0) == error_mark_node)
6088 return error_mark_node;
6089 TREE_OPERAND (rhs, 1)
6090 = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags);
6091 if (TREE_OPERAND (rhs, 1) == error_mark_node)
6092 return error_mark_node;
6094 TREE_TYPE (rhs) = lhstype;
6099 if (PTRMEM_OK_P (rhs))
6100 flags |= tf_ptrmem_ok;
6102 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6106 return error_mark_node;
6111 return error_mark_node;
6114 /* Return the name of the virtual function pointer field
6115 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6116 this may have to look back through base types to find the
6117 ultimate field name. (For single inheritance, these could
6118 all be the same name. Who knows for multiple inheritance). */
6121 get_vfield_name (tree type)
6123 tree binfo, base_binfo;
6126 for (binfo = TYPE_BINFO (type);
6127 BINFO_N_BASE_BINFOS (binfo);
6130 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6132 if (BINFO_VIRTUAL_P (base_binfo)
6133 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6137 type = BINFO_TYPE (binfo);
6138 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6139 + TYPE_NAME_LENGTH (type) + 2);
6140 sprintf (buf, VFIELD_NAME_FORMAT,
6141 IDENTIFIER_POINTER (constructor_name (type)));
6142 return get_identifier (buf);
6146 print_class_statistics (void)
6148 #ifdef GATHER_STATISTICS
6149 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6150 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6153 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6154 n_vtables, n_vtable_searches);
6155 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6156 n_vtable_entries, n_vtable_elems);
6161 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6162 according to [class]:
6163 The class-name is also inserted
6164 into the scope of the class itself. For purposes of access checking,
6165 the inserted class name is treated as if it were a public member name. */
6168 build_self_reference (void)
6170 tree name = constructor_name (current_class_type);
6171 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6174 DECL_NONLOCAL (value) = 1;
6175 DECL_CONTEXT (value) = current_class_type;
6176 DECL_ARTIFICIAL (value) = 1;
6177 SET_DECL_SELF_REFERENCE_P (value);
6179 if (processing_template_decl)
6180 value = push_template_decl (value);
6182 saved_cas = current_access_specifier;
6183 current_access_specifier = access_public_node;
6184 finish_member_declaration (value);
6185 current_access_specifier = saved_cas;
6188 /* Returns 1 if TYPE contains only padding bytes. */
6191 is_empty_class (tree type)
6193 if (type == error_mark_node)
6196 if (! IS_AGGR_TYPE (type))
6199 /* In G++ 3.2, whether or not a class was empty was determined by
6200 looking at its size. */
6201 if (abi_version_at_least (2))
6202 return CLASSTYPE_EMPTY_P (type);
6204 return integer_zerop (CLASSTYPE_SIZE (type));
6207 /* Returns true if TYPE contains an empty class. */
6210 contains_empty_class_p (tree type)
6212 if (is_empty_class (type))
6214 if (CLASS_TYPE_P (type))
6221 for (binfo = TYPE_BINFO (type), i = 0;
6222 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6223 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6225 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6226 if (TREE_CODE (field) == FIELD_DECL
6227 && !DECL_ARTIFICIAL (field)
6228 && is_empty_class (TREE_TYPE (field)))
6231 else if (TREE_CODE (type) == ARRAY_TYPE)
6232 return contains_empty_class_p (TREE_TYPE (type));
6236 /* Note that NAME was looked up while the current class was being
6237 defined and that the result of that lookup was DECL. */
6240 maybe_note_name_used_in_class (tree name, tree decl)
6242 splay_tree names_used;
6244 /* If we're not defining a class, there's nothing to do. */
6245 if (!(innermost_scope_kind() == sk_class
6246 && TYPE_BEING_DEFINED (current_class_type)))
6249 /* If there's already a binding for this NAME, then we don't have
6250 anything to worry about. */
6251 if (lookup_member (current_class_type, name,
6252 /*protect=*/0, /*want_type=*/false))
6255 if (!current_class_stack[current_class_depth - 1].names_used)
6256 current_class_stack[current_class_depth - 1].names_used
6257 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6258 names_used = current_class_stack[current_class_depth - 1].names_used;
6260 splay_tree_insert (names_used,
6261 (splay_tree_key) name,
6262 (splay_tree_value) decl);
6265 /* Note that NAME was declared (as DECL) in the current class. Check
6266 to see that the declaration is valid. */
6269 note_name_declared_in_class (tree name, tree decl)
6271 splay_tree names_used;
6274 /* Look to see if we ever used this name. */
6276 = current_class_stack[current_class_depth - 1].names_used;
6280 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6283 /* [basic.scope.class]
6285 A name N used in a class S shall refer to the same declaration
6286 in its context and when re-evaluated in the completed scope of
6288 error ("declaration of %q#D", decl);
6289 error ("changes meaning of %qD from %q+#D",
6290 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6294 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6295 Secondary vtables are merged with primary vtables; this function
6296 will return the VAR_DECL for the primary vtable. */
6299 get_vtbl_decl_for_binfo (tree binfo)
6303 decl = BINFO_VTABLE (binfo);
6304 if (decl && TREE_CODE (decl) == PLUS_EXPR)
6306 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6307 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6310 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6315 /* Returns the binfo for the primary base of BINFO. If the resulting
6316 BINFO is a virtual base, and it is inherited elsewhere in the
6317 hierarchy, then the returned binfo might not be the primary base of
6318 BINFO in the complete object. Check BINFO_PRIMARY_P or
6319 BINFO_LOST_PRIMARY_P to be sure. */
6322 get_primary_binfo (tree binfo)
6326 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6330 return copied_binfo (primary_base, binfo);
6333 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6336 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6339 fprintf (stream, "%*s", indent, "");
6343 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6344 INDENT should be zero when called from the top level; it is
6345 incremented recursively. IGO indicates the next expected BINFO in
6346 inheritance graph ordering. */
6349 dump_class_hierarchy_r (FILE *stream,
6359 indented = maybe_indent_hierarchy (stream, indent, 0);
6360 fprintf (stream, "%s (0x%lx) ",
6361 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6362 (unsigned long) binfo);
6365 fprintf (stream, "alternative-path\n");
6368 igo = TREE_CHAIN (binfo);
6370 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6371 tree_low_cst (BINFO_OFFSET (binfo), 0));
6372 if (is_empty_class (BINFO_TYPE (binfo)))
6373 fprintf (stream, " empty");
6374 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6375 fprintf (stream, " nearly-empty");
6376 if (BINFO_VIRTUAL_P (binfo))
6377 fprintf (stream, " virtual");
6378 fprintf (stream, "\n");
6381 if (BINFO_PRIMARY_P (binfo))
6383 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6384 fprintf (stream, " primary-for %s (0x%lx)",
6385 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6386 TFF_PLAIN_IDENTIFIER),
6387 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6389 if (BINFO_LOST_PRIMARY_P (binfo))
6391 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6392 fprintf (stream, " lost-primary");
6395 fprintf (stream, "\n");
6397 if (!(flags & TDF_SLIM))
6401 if (BINFO_SUBVTT_INDEX (binfo))
6403 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6404 fprintf (stream, " subvttidx=%s",
6405 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6406 TFF_PLAIN_IDENTIFIER));
6408 if (BINFO_VPTR_INDEX (binfo))
6410 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6411 fprintf (stream, " vptridx=%s",
6412 expr_as_string (BINFO_VPTR_INDEX (binfo),
6413 TFF_PLAIN_IDENTIFIER));
6415 if (BINFO_VPTR_FIELD (binfo))
6417 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6418 fprintf (stream, " vbaseoffset=%s",
6419 expr_as_string (BINFO_VPTR_FIELD (binfo),
6420 TFF_PLAIN_IDENTIFIER));
6422 if (BINFO_VTABLE (binfo))
6424 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6425 fprintf (stream, " vptr=%s",
6426 expr_as_string (BINFO_VTABLE (binfo),
6427 TFF_PLAIN_IDENTIFIER));
6431 fprintf (stream, "\n");
6434 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6435 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6440 /* Dump the BINFO hierarchy for T. */
6443 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6445 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6446 fprintf (stream, " size=%lu align=%lu\n",
6447 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6448 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6449 fprintf (stream, " base size=%lu base align=%lu\n",
6450 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6452 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6454 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6455 fprintf (stream, "\n");
6458 /* Debug interface to hierarchy dumping. */
6461 debug_class (tree t)
6463 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6467 dump_class_hierarchy (tree t)
6470 FILE *stream = dump_begin (TDI_class, &flags);
6474 dump_class_hierarchy_1 (stream, flags, t);
6475 dump_end (TDI_class, stream);
6480 dump_array (FILE * stream, tree decl)
6483 unsigned HOST_WIDE_INT ix;
6485 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6487 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6489 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6490 fprintf (stream, " %s entries",
6491 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6492 TFF_PLAIN_IDENTIFIER));
6493 fprintf (stream, "\n");
6495 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
6497 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
6498 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
6502 dump_vtable (tree t, tree binfo, tree vtable)
6505 FILE *stream = dump_begin (TDI_class, &flags);
6510 if (!(flags & TDF_SLIM))
6512 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6514 fprintf (stream, "%s for %s",
6515 ctor_vtbl_p ? "Construction vtable" : "Vtable",
6516 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6519 if (!BINFO_VIRTUAL_P (binfo))
6520 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6521 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6523 fprintf (stream, "\n");
6524 dump_array (stream, vtable);
6525 fprintf (stream, "\n");
6528 dump_end (TDI_class, stream);
6532 dump_vtt (tree t, tree vtt)
6535 FILE *stream = dump_begin (TDI_class, &flags);
6540 if (!(flags & TDF_SLIM))
6542 fprintf (stream, "VTT for %s\n",
6543 type_as_string (t, TFF_PLAIN_IDENTIFIER));
6544 dump_array (stream, vtt);
6545 fprintf (stream, "\n");
6548 dump_end (TDI_class, stream);
6551 /* Dump a function or thunk and its thunkees. */
6554 dump_thunk (FILE *stream, int indent, tree thunk)
6556 static const char spaces[] = " ";
6557 tree name = DECL_NAME (thunk);
6560 fprintf (stream, "%.*s%p %s %s", indent, spaces,
6562 !DECL_THUNK_P (thunk) ? "function"
6563 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6564 name ? IDENTIFIER_POINTER (name) : "<unset>");
6565 if (DECL_THUNK_P (thunk))
6567 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6568 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6570 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6571 if (!virtual_adjust)
6573 else if (DECL_THIS_THUNK_P (thunk))
6574 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
6575 tree_low_cst (virtual_adjust, 0));
6577 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6578 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6579 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6580 if (THUNK_ALIAS (thunk))
6581 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6583 fprintf (stream, "\n");
6584 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6585 dump_thunk (stream, indent + 2, thunks);
6588 /* Dump the thunks for FN. */
6591 debug_thunks (tree fn)
6593 dump_thunk (stderr, 0, fn);
6596 /* Virtual function table initialization. */
6598 /* Create all the necessary vtables for T and its base classes. */
6601 finish_vtbls (tree t)
6606 /* We lay out the primary and secondary vtables in one contiguous
6607 vtable. The primary vtable is first, followed by the non-virtual
6608 secondary vtables in inheritance graph order. */
6609 list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6610 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6611 TYPE_BINFO (t), t, list);
6613 /* Then come the virtual bases, also in inheritance graph order. */
6614 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6616 if (!BINFO_VIRTUAL_P (vbase))
6618 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6621 if (BINFO_VTABLE (TYPE_BINFO (t)))
6622 initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
6625 /* Initialize the vtable for BINFO with the INITS. */
6628 initialize_vtable (tree binfo, tree inits)
6632 layout_vtable_decl (binfo, list_length (inits));
6633 decl = get_vtbl_decl_for_binfo (binfo);
6634 initialize_artificial_var (decl, inits);
6635 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
6638 /* Build the VTT (virtual table table) for T.
6639 A class requires a VTT if it has virtual bases.
6642 1 - primary virtual pointer for complete object T
6643 2 - secondary VTTs for each direct non-virtual base of T which requires a
6645 3 - secondary virtual pointers for each direct or indirect base of T which
6646 has virtual bases or is reachable via a virtual path from T.
6647 4 - secondary VTTs for each direct or indirect virtual base of T.
6649 Secondary VTTs look like complete object VTTs without part 4. */
6659 /* Build up the initializers for the VTT. */
6661 index = size_zero_node;
6662 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
6664 /* If we didn't need a VTT, we're done. */
6668 /* Figure out the type of the VTT. */
6669 type = build_index_type (size_int (list_length (inits) - 1));
6670 type = build_cplus_array_type (const_ptr_type_node, type);
6672 /* Now, build the VTT object itself. */
6673 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
6674 initialize_artificial_var (vtt, inits);
6675 /* Add the VTT to the vtables list. */
6676 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
6677 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
6682 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
6683 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
6684 and CHAIN the vtable pointer for this binfo after construction is
6685 complete. VALUE can also be another BINFO, in which case we recurse. */
6688 binfo_ctor_vtable (tree binfo)
6694 vt = BINFO_VTABLE (binfo);
6695 if (TREE_CODE (vt) == TREE_LIST)
6696 vt = TREE_VALUE (vt);
6697 if (TREE_CODE (vt) == TREE_BINFO)
6706 /* Data for secondary VTT initialization. */
6707 typedef struct secondary_vptr_vtt_init_data_s
6709 /* Is this the primary VTT? */
6712 /* Current index into the VTT. */
6715 /* TREE_LIST of initializers built up. */
6718 /* The type being constructed by this secondary VTT. */
6719 tree type_being_constructed;
6720 } secondary_vptr_vtt_init_data;
6722 /* Recursively build the VTT-initializer for BINFO (which is in the
6723 hierarchy dominated by T). INITS points to the end of the initializer
6724 list to date. INDEX is the VTT index where the next element will be
6725 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
6726 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
6727 for virtual bases of T. When it is not so, we build the constructor
6728 vtables for the BINFO-in-T variant. */
6731 build_vtt_inits (tree binfo, tree t, tree *inits, tree *index)
6736 tree secondary_vptrs;
6737 secondary_vptr_vtt_init_data data;
6738 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
6740 /* We only need VTTs for subobjects with virtual bases. */
6741 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
6744 /* We need to use a construction vtable if this is not the primary
6748 build_ctor_vtbl_group (binfo, t);
6750 /* Record the offset in the VTT where this sub-VTT can be found. */
6751 BINFO_SUBVTT_INDEX (binfo) = *index;
6754 /* Add the address of the primary vtable for the complete object. */
6755 init = binfo_ctor_vtable (binfo);
6756 *inits = build_tree_list (NULL_TREE, init);
6757 inits = &TREE_CHAIN (*inits);
6760 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6761 BINFO_VPTR_INDEX (binfo) = *index;
6763 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
6765 /* Recursively add the secondary VTTs for non-virtual bases. */
6766 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
6767 if (!BINFO_VIRTUAL_P (b))
6768 inits = build_vtt_inits (b, t, inits, index);
6770 /* Add secondary virtual pointers for all subobjects of BINFO with
6771 either virtual bases or reachable along a virtual path, except
6772 subobjects that are non-virtual primary bases. */
6773 data.top_level_p = top_level_p;
6774 data.index = *index;
6776 data.type_being_constructed = BINFO_TYPE (binfo);
6778 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
6780 *index = data.index;
6782 /* The secondary vptrs come back in reverse order. After we reverse
6783 them, and add the INITS, the last init will be the first element
6785 secondary_vptrs = data.inits;
6786 if (secondary_vptrs)
6788 *inits = nreverse (secondary_vptrs);
6789 inits = &TREE_CHAIN (secondary_vptrs);
6790 gcc_assert (*inits == NULL_TREE);
6794 /* Add the secondary VTTs for virtual bases in inheritance graph
6796 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
6798 if (!BINFO_VIRTUAL_P (b))
6801 inits = build_vtt_inits (b, t, inits, index);
6804 /* Remove the ctor vtables we created. */
6805 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
6810 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
6811 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
6814 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
6816 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
6818 /* We don't care about bases that don't have vtables. */
6819 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
6820 return dfs_skip_bases;
6822 /* We're only interested in proper subobjects of the type being
6824 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
6827 /* We're only interested in bases with virtual bases or reachable
6828 via a virtual path from the type being constructed. */
6829 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
6830 || binfo_via_virtual (binfo, data->type_being_constructed)))
6831 return dfs_skip_bases;
6833 /* We're not interested in non-virtual primary bases. */
6834 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
6837 /* Record the index where this secondary vptr can be found. */
6838 if (data->top_level_p)
6840 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6841 BINFO_VPTR_INDEX (binfo) = data->index;
6843 if (BINFO_VIRTUAL_P (binfo))
6845 /* It's a primary virtual base, and this is not a
6846 construction vtable. Find the base this is primary of in
6847 the inheritance graph, and use that base's vtable
6849 while (BINFO_PRIMARY_P (binfo))
6850 binfo = BINFO_INHERITANCE_CHAIN (binfo);
6854 /* Add the initializer for the secondary vptr itself. */
6855 data->inits = tree_cons (NULL_TREE, binfo_ctor_vtable (binfo), data->inits);
6857 /* Advance the vtt index. */
6858 data->index = size_binop (PLUS_EXPR, data->index,
6859 TYPE_SIZE_UNIT (ptr_type_node));
6864 /* Called from build_vtt_inits via dfs_walk. After building
6865 constructor vtables and generating the sub-vtt from them, we need
6866 to restore the BINFO_VTABLES that were scribbled on. DATA is the
6867 binfo of the base whose sub vtt was generated. */
6870 dfs_fixup_binfo_vtbls (tree binfo, void* data)
6872 tree vtable = BINFO_VTABLE (binfo);
6874 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
6875 /* If this class has no vtable, none of its bases do. */
6876 return dfs_skip_bases;
6879 /* This might be a primary base, so have no vtable in this
6883 /* If we scribbled the construction vtable vptr into BINFO, clear it
6885 if (TREE_CODE (vtable) == TREE_LIST
6886 && (TREE_PURPOSE (vtable) == (tree) data))
6887 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
6892 /* Build the construction vtable group for BINFO which is in the
6893 hierarchy dominated by T. */
6896 build_ctor_vtbl_group (tree binfo, tree t)
6905 /* See if we've already created this construction vtable group. */
6906 id = mangle_ctor_vtbl_for_type (t, binfo);
6907 if (IDENTIFIER_GLOBAL_VALUE (id))
6910 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
6911 /* Build a version of VTBL (with the wrong type) for use in
6912 constructing the addresses of secondary vtables in the
6913 construction vtable group. */
6914 vtbl = build_vtable (t, id, ptr_type_node);
6915 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
6916 list = build_tree_list (vtbl, NULL_TREE);
6917 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
6920 /* Add the vtables for each of our virtual bases using the vbase in T
6922 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
6924 vbase = TREE_CHAIN (vbase))
6928 if (!BINFO_VIRTUAL_P (vbase))
6930 b = copied_binfo (vbase, binfo);
6932 accumulate_vtbl_inits (b, vbase, binfo, t, list);
6934 inits = TREE_VALUE (list);
6936 /* Figure out the type of the construction vtable. */
6937 type = build_index_type (size_int (list_length (inits) - 1));
6938 type = build_cplus_array_type (vtable_entry_type, type);
6939 TREE_TYPE (vtbl) = type;
6941 /* Initialize the construction vtable. */
6942 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
6943 initialize_artificial_var (vtbl, inits);
6944 dump_vtable (t, binfo, vtbl);
6947 /* Add the vtbl initializers for BINFO (and its bases other than
6948 non-virtual primaries) to the list of INITS. BINFO is in the
6949 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
6950 the constructor the vtbl inits should be accumulated for. (If this
6951 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
6952 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
6953 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
6954 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
6955 but are not necessarily the same in terms of layout. */
6958 accumulate_vtbl_inits (tree binfo,
6966 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
6968 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
6970 /* If it doesn't have a vptr, we don't do anything. */
6971 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
6974 /* If we're building a construction vtable, we're not interested in
6975 subobjects that don't require construction vtables. */
6977 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
6978 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
6981 /* Build the initializers for the BINFO-in-T vtable. */
6983 = chainon (TREE_VALUE (inits),
6984 dfs_accumulate_vtbl_inits (binfo, orig_binfo,
6985 rtti_binfo, t, inits));
6987 /* Walk the BINFO and its bases. We walk in preorder so that as we
6988 initialize each vtable we can figure out at what offset the
6989 secondary vtable lies from the primary vtable. We can't use
6990 dfs_walk here because we need to iterate through bases of BINFO
6991 and RTTI_BINFO simultaneously. */
6992 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6994 /* Skip virtual bases. */
6995 if (BINFO_VIRTUAL_P (base_binfo))
6997 accumulate_vtbl_inits (base_binfo,
6998 BINFO_BASE_BINFO (orig_binfo, i),
7004 /* Called from accumulate_vtbl_inits. Returns the initializers for
7005 the BINFO vtable. */
7008 dfs_accumulate_vtbl_inits (tree binfo,
7014 tree inits = NULL_TREE;
7015 tree vtbl = NULL_TREE;
7016 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7019 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7021 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7022 primary virtual base. If it is not the same primary in
7023 the hierarchy of T, we'll need to generate a ctor vtable
7024 for it, to place at its location in T. If it is the same
7025 primary, we still need a VTT entry for the vtable, but it
7026 should point to the ctor vtable for the base it is a
7027 primary for within the sub-hierarchy of RTTI_BINFO.
7029 There are three possible cases:
7031 1) We are in the same place.
7032 2) We are a primary base within a lost primary virtual base of
7034 3) We are primary to something not a base of RTTI_BINFO. */
7037 tree last = NULL_TREE;
7039 /* First, look through the bases we are primary to for RTTI_BINFO
7040 or a virtual base. */
7042 while (BINFO_PRIMARY_P (b))
7044 b = BINFO_INHERITANCE_CHAIN (b);
7046 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7049 /* If we run out of primary links, keep looking down our
7050 inheritance chain; we might be an indirect primary. */
7051 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7052 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7056 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7057 base B and it is a base of RTTI_BINFO, this is case 2. In
7058 either case, we share our vtable with LAST, i.e. the
7059 derived-most base within B of which we are a primary. */
7061 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7062 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7063 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7064 binfo_ctor_vtable after everything's been set up. */
7067 /* Otherwise, this is case 3 and we get our own. */
7069 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7077 /* Compute the initializer for this vtable. */
7078 inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7081 /* Figure out the position to which the VPTR should point. */
7082 vtbl = TREE_PURPOSE (l);
7083 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7084 index = size_binop (PLUS_EXPR,
7085 size_int (non_fn_entries),
7086 size_int (list_length (TREE_VALUE (l))));
7087 index = size_binop (MULT_EXPR,
7088 TYPE_SIZE_UNIT (vtable_entry_type),
7090 vtbl = build2 (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7094 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7095 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7096 straighten this out. */
7097 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7098 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7101 /* For an ordinary vtable, set BINFO_VTABLE. */
7102 BINFO_VTABLE (binfo) = vtbl;
7107 static GTY(()) tree abort_fndecl_addr;
7109 /* Construct the initializer for BINFO's virtual function table. BINFO
7110 is part of the hierarchy dominated by T. If we're building a
7111 construction vtable, the ORIG_BINFO is the binfo we should use to
7112 find the actual function pointers to put in the vtable - but they
7113 can be overridden on the path to most-derived in the graph that
7114 ORIG_BINFO belongs. Otherwise,
7115 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7116 BINFO that should be indicated by the RTTI information in the
7117 vtable; it will be a base class of T, rather than T itself, if we
7118 are building a construction vtable.
7120 The value returned is a TREE_LIST suitable for wrapping in a
7121 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7122 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7123 number of non-function entries in the vtable.
7125 It might seem that this function should never be called with a
7126 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7127 base is always subsumed by a derived class vtable. However, when
7128 we are building construction vtables, we do build vtables for
7129 primary bases; we need these while the primary base is being
7133 build_vtbl_initializer (tree binfo,
7137 int* non_fn_entries_p)
7144 VEC(tree,gc) *vbases;
7146 /* Initialize VID. */
7147 memset (&vid, 0, sizeof (vid));
7150 vid.rtti_binfo = rtti_binfo;
7151 vid.last_init = &vid.inits;
7152 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7153 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7154 vid.generate_vcall_entries = true;
7155 /* The first vbase or vcall offset is at index -3 in the vtable. */
7156 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7158 /* Add entries to the vtable for RTTI. */
7159 build_rtti_vtbl_entries (binfo, &vid);
7161 /* Create an array for keeping track of the functions we've
7162 processed. When we see multiple functions with the same
7163 signature, we share the vcall offsets. */
7164 vid.fns = VEC_alloc (tree, gc, 32);
7165 /* Add the vcall and vbase offset entries. */
7166 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7168 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7169 build_vbase_offset_vtbl_entries. */
7170 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7171 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7172 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7174 /* If the target requires padding between data entries, add that now. */
7175 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7179 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7184 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7185 add = tree_cons (NULL_TREE,
7186 build1 (NOP_EXPR, vtable_entry_type,
7193 if (non_fn_entries_p)
7194 *non_fn_entries_p = list_length (vid.inits);
7196 /* Go through all the ordinary virtual functions, building up
7198 vfun_inits = NULL_TREE;
7199 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7203 tree fn, fn_original;
7204 tree init = NULL_TREE;
7208 if (DECL_THUNK_P (fn))
7210 if (!DECL_NAME (fn))
7212 if (THUNK_ALIAS (fn))
7214 fn = THUNK_ALIAS (fn);
7217 fn_original = THUNK_TARGET (fn);
7220 /* If the only definition of this function signature along our
7221 primary base chain is from a lost primary, this vtable slot will
7222 never be used, so just zero it out. This is important to avoid
7223 requiring extra thunks which cannot be generated with the function.
7225 We first check this in update_vtable_entry_for_fn, so we handle
7226 restored primary bases properly; we also need to do it here so we
7227 zero out unused slots in ctor vtables, rather than filling themff
7228 with erroneous values (though harmless, apart from relocation
7230 for (b = binfo; ; b = get_primary_binfo (b))
7232 /* We found a defn before a lost primary; go ahead as normal. */
7233 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7236 /* The nearest definition is from a lost primary; clear the
7238 if (BINFO_LOST_PRIMARY_P (b))
7240 init = size_zero_node;
7247 /* Pull the offset for `this', and the function to call, out of
7249 delta = BV_DELTA (v);
7250 vcall_index = BV_VCALL_INDEX (v);
7252 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7253 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7255 /* You can't call an abstract virtual function; it's abstract.
7256 So, we replace these functions with __pure_virtual. */
7257 if (DECL_PURE_VIRTUAL_P (fn_original))
7260 if (abort_fndecl_addr == NULL)
7261 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7262 init = abort_fndecl_addr;
7266 if (!integer_zerop (delta) || vcall_index)
7268 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7269 if (!DECL_NAME (fn))
7272 /* Take the address of the function, considering it to be of an
7273 appropriate generic type. */
7274 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7278 /* And add it to the chain of initializers. */
7279 if (TARGET_VTABLE_USES_DESCRIPTORS)
7282 if (init == size_zero_node)
7283 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7284 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7286 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7288 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7289 TREE_OPERAND (init, 0),
7290 build_int_cst (NULL_TREE, i));
7291 TREE_CONSTANT (fdesc) = 1;
7292 TREE_INVARIANT (fdesc) = 1;
7294 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7298 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7301 /* The initializers for virtual functions were built up in reverse
7302 order; straighten them out now. */
7303 vfun_inits = nreverse (vfun_inits);
7305 /* The negative offset initializers are also in reverse order. */
7306 vid.inits = nreverse (vid.inits);
7308 /* Chain the two together. */
7309 return chainon (vid.inits, vfun_inits);
7312 /* Adds to vid->inits the initializers for the vbase and vcall
7313 offsets in BINFO, which is in the hierarchy dominated by T. */
7316 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7320 /* If this is a derived class, we must first create entries
7321 corresponding to the primary base class. */
7322 b = get_primary_binfo (binfo);
7324 build_vcall_and_vbase_vtbl_entries (b, vid);
7326 /* Add the vbase entries for this base. */
7327 build_vbase_offset_vtbl_entries (binfo, vid);
7328 /* Add the vcall entries for this base. */
7329 build_vcall_offset_vtbl_entries (binfo, vid);
7332 /* Returns the initializers for the vbase offset entries in the vtable
7333 for BINFO (which is part of the class hierarchy dominated by T), in
7334 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7335 where the next vbase offset will go. */
7338 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7342 tree non_primary_binfo;
7344 /* If there are no virtual baseclasses, then there is nothing to
7346 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7351 /* We might be a primary base class. Go up the inheritance hierarchy
7352 until we find the most derived class of which we are a primary base:
7353 it is the offset of that which we need to use. */
7354 non_primary_binfo = binfo;
7355 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7359 /* If we have reached a virtual base, then it must be a primary
7360 base (possibly multi-level) of vid->binfo, or we wouldn't
7361 have called build_vcall_and_vbase_vtbl_entries for it. But it
7362 might be a lost primary, so just skip down to vid->binfo. */
7363 if (BINFO_VIRTUAL_P (non_primary_binfo))
7365 non_primary_binfo = vid->binfo;
7369 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7370 if (get_primary_binfo (b) != non_primary_binfo)
7372 non_primary_binfo = b;
7375 /* Go through the virtual bases, adding the offsets. */
7376 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7378 vbase = TREE_CHAIN (vbase))
7383 if (!BINFO_VIRTUAL_P (vbase))
7386 /* Find the instance of this virtual base in the complete
7388 b = copied_binfo (vbase, binfo);
7390 /* If we've already got an offset for this virtual base, we
7391 don't need another one. */
7392 if (BINFO_VTABLE_PATH_MARKED (b))
7394 BINFO_VTABLE_PATH_MARKED (b) = 1;
7396 /* Figure out where we can find this vbase offset. */
7397 delta = size_binop (MULT_EXPR,
7400 TYPE_SIZE_UNIT (vtable_entry_type)));
7401 if (vid->primary_vtbl_p)
7402 BINFO_VPTR_FIELD (b) = delta;
7404 if (binfo != TYPE_BINFO (t))
7405 /* The vbase offset had better be the same. */
7406 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7408 /* The next vbase will come at a more negative offset. */
7409 vid->index = size_binop (MINUS_EXPR, vid->index,
7410 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7412 /* The initializer is the delta from BINFO to this virtual base.
7413 The vbase offsets go in reverse inheritance-graph order, and
7414 we are walking in inheritance graph order so these end up in
7416 delta = size_diffop (BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7419 = build_tree_list (NULL_TREE,
7420 fold_build1 (NOP_EXPR,
7423 vid->last_init = &TREE_CHAIN (*vid->last_init);
7427 /* Adds the initializers for the vcall offset entries in the vtable
7428 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7432 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7434 /* We only need these entries if this base is a virtual base. We
7435 compute the indices -- but do not add to the vtable -- when
7436 building the main vtable for a class. */
7437 if (BINFO_VIRTUAL_P (binfo) || binfo == TYPE_BINFO (vid->derived))
7439 /* We need a vcall offset for each of the virtual functions in this
7440 vtable. For example:
7442 class A { virtual void f (); };
7443 class B1 : virtual public A { virtual void f (); };
7444 class B2 : virtual public A { virtual void f (); };
7445 class C: public B1, public B2 { virtual void f (); };
7447 A C object has a primary base of B1, which has a primary base of A. A
7448 C also has a secondary base of B2, which no longer has a primary base
7449 of A. So the B2-in-C construction vtable needs a secondary vtable for
7450 A, which will adjust the A* to a B2* to call f. We have no way of
7451 knowing what (or even whether) this offset will be when we define B2,
7452 so we store this "vcall offset" in the A sub-vtable and look it up in
7453 a "virtual thunk" for B2::f.
7455 We need entries for all the functions in our primary vtable and
7456 in our non-virtual bases' secondary vtables. */
7458 /* If we are just computing the vcall indices -- but do not need
7459 the actual entries -- not that. */
7460 if (!BINFO_VIRTUAL_P (binfo))
7461 vid->generate_vcall_entries = false;
7462 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7463 add_vcall_offset_vtbl_entries_r (binfo, vid);
7467 /* Build vcall offsets, starting with those for BINFO. */
7470 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7476 /* Don't walk into virtual bases -- except, of course, for the
7477 virtual base for which we are building vcall offsets. Any
7478 primary virtual base will have already had its offsets generated
7479 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7480 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7483 /* If BINFO has a primary base, process it first. */
7484 primary_binfo = get_primary_binfo (binfo);
7486 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7488 /* Add BINFO itself to the list. */
7489 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7491 /* Scan the non-primary bases of BINFO. */
7492 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7493 if (base_binfo != primary_binfo)
7494 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7497 /* Called from build_vcall_offset_vtbl_entries_r. */
7500 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7502 /* Make entries for the rest of the virtuals. */
7503 if (abi_version_at_least (2))
7507 /* The ABI requires that the methods be processed in declaration
7508 order. G++ 3.2 used the order in the vtable. */
7509 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7511 orig_fn = TREE_CHAIN (orig_fn))
7512 if (DECL_VINDEX (orig_fn))
7513 add_vcall_offset (orig_fn, binfo, vid);
7517 tree derived_virtuals;
7520 /* If BINFO is a primary base, the most derived class which has
7521 BINFO as a primary base; otherwise, just BINFO. */
7522 tree non_primary_binfo;
7524 /* We might be a primary base class. Go up the inheritance hierarchy
7525 until we find the most derived class of which we are a primary base:
7526 it is the BINFO_VIRTUALS there that we need to consider. */
7527 non_primary_binfo = binfo;
7528 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7532 /* If we have reached a virtual base, then it must be vid->vbase,
7533 because we ignore other virtual bases in
7534 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7535 base (possibly multi-level) of vid->binfo, or we wouldn't
7536 have called build_vcall_and_vbase_vtbl_entries for it. But it
7537 might be a lost primary, so just skip down to vid->binfo. */
7538 if (BINFO_VIRTUAL_P (non_primary_binfo))
7540 gcc_assert (non_primary_binfo == vid->vbase);
7541 non_primary_binfo = vid->binfo;
7545 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7546 if (get_primary_binfo (b) != non_primary_binfo)
7548 non_primary_binfo = b;
7551 if (vid->ctor_vtbl_p)
7552 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7553 where rtti_binfo is the most derived type. */
7555 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7557 for (base_virtuals = BINFO_VIRTUALS (binfo),
7558 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7559 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7561 base_virtuals = TREE_CHAIN (base_virtuals),
7562 derived_virtuals = TREE_CHAIN (derived_virtuals),
7563 orig_virtuals = TREE_CHAIN (orig_virtuals))
7567 /* Find the declaration that originally caused this function to
7568 be present in BINFO_TYPE (binfo). */
7569 orig_fn = BV_FN (orig_virtuals);
7571 /* When processing BINFO, we only want to generate vcall slots for
7572 function slots introduced in BINFO. So don't try to generate
7573 one if the function isn't even defined in BINFO. */
7574 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7577 add_vcall_offset (orig_fn, binfo, vid);
7582 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7585 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7591 /* If there is already an entry for a function with the same
7592 signature as FN, then we do not need a second vcall offset.
7593 Check the list of functions already present in the derived
7595 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7597 if (same_signature_p (derived_entry, orig_fn)
7598 /* We only use one vcall offset for virtual destructors,
7599 even though there are two virtual table entries. */
7600 || (DECL_DESTRUCTOR_P (derived_entry)
7601 && DECL_DESTRUCTOR_P (orig_fn)))
7605 /* If we are building these vcall offsets as part of building
7606 the vtable for the most derived class, remember the vcall
7608 if (vid->binfo == TYPE_BINFO (vid->derived))
7610 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
7611 CLASSTYPE_VCALL_INDICES (vid->derived),
7613 elt->purpose = orig_fn;
7614 elt->value = vid->index;
7617 /* The next vcall offset will be found at a more negative
7619 vid->index = size_binop (MINUS_EXPR, vid->index,
7620 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7622 /* Keep track of this function. */
7623 VEC_safe_push (tree, gc, vid->fns, orig_fn);
7625 if (vid->generate_vcall_entries)
7630 /* Find the overriding function. */
7631 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
7632 if (fn == error_mark_node)
7633 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
7637 base = TREE_VALUE (fn);
7639 /* The vbase we're working on is a primary base of
7640 vid->binfo. But it might be a lost primary, so its
7641 BINFO_OFFSET might be wrong, so we just use the
7642 BINFO_OFFSET from vid->binfo. */
7643 vcall_offset = size_diffop (BINFO_OFFSET (base),
7644 BINFO_OFFSET (vid->binfo));
7645 vcall_offset = fold_build1 (NOP_EXPR, vtable_entry_type,
7648 /* Add the initializer to the vtable. */
7649 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
7650 vid->last_init = &TREE_CHAIN (*vid->last_init);
7654 /* Return vtbl initializers for the RTTI entries corresponding to the
7655 BINFO's vtable. The RTTI entries should indicate the object given
7656 by VID->rtti_binfo. */
7659 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
7668 basetype = BINFO_TYPE (binfo);
7669 t = BINFO_TYPE (vid->rtti_binfo);
7671 /* To find the complete object, we will first convert to our most
7672 primary base, and then add the offset in the vtbl to that value. */
7674 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
7675 && !BINFO_LOST_PRIMARY_P (b))
7679 primary_base = get_primary_binfo (b);
7680 gcc_assert (BINFO_PRIMARY_P (primary_base)
7681 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
7684 offset = size_diffop (BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
7686 /* The second entry is the address of the typeinfo object. */
7688 decl = build_address (get_tinfo_decl (t));
7690 decl = integer_zero_node;
7692 /* Convert the declaration to a type that can be stored in the
7694 init = build_nop (vfunc_ptr_type_node, decl);
7695 *vid->last_init = build_tree_list (NULL_TREE, init);
7696 vid->last_init = &TREE_CHAIN (*vid->last_init);
7698 /* Add the offset-to-top entry. It comes earlier in the vtable than
7699 the typeinfo entry. Convert the offset to look like a
7700 function pointer, so that we can put it in the vtable. */
7701 init = build_nop (vfunc_ptr_type_node, offset);
7702 *vid->last_init = build_tree_list (NULL_TREE, init);
7703 vid->last_init = &TREE_CHAIN (*vid->last_init);
7706 /* Fold a OBJ_TYPE_REF expression to the address of a function.
7707 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
7710 cp_fold_obj_type_ref (tree ref, tree known_type)
7712 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
7713 HOST_WIDE_INT i = 0;
7714 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
7719 i += (TARGET_VTABLE_USES_DESCRIPTORS
7720 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
7726 #ifdef ENABLE_CHECKING
7727 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
7728 DECL_VINDEX (fndecl)));
7731 cgraph_node (fndecl)->local.vtable_method = true;
7733 return build_address (fndecl);
7736 #include "gt-cp-class.h"