1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
39 #include "tree-dump.h"
41 /* The number of nested classes being processed. If we are not in the
42 scope of any class, this is zero. */
44 int current_class_depth;
46 /* In order to deal with nested classes, we keep a stack of classes.
47 The topmost entry is the innermost class, and is the entry at index
48 CURRENT_CLASS_DEPTH */
50 typedef struct class_stack_node {
51 /* The name of the class. */
54 /* The _TYPE node for the class. */
57 /* The access specifier pending for new declarations in the scope of
61 /* If were defining TYPE, the names used in this class. */
62 splay_tree names_used;
64 /* Nonzero if this class is no longer open, because of a call to
67 }* class_stack_node_t;
69 typedef struct vtbl_init_data_s
71 /* The base for which we're building initializers. */
73 /* The type of the most-derived type. */
75 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
76 unless ctor_vtbl_p is true. */
78 /* The negative-index vtable initializers built up so far. These
79 are in order from least negative index to most negative index. */
81 /* The last (i.e., most negative) entry in INITS. */
83 /* The binfo for the virtual base for which we're building
84 vcall offset initializers. */
86 /* The functions in vbase for which we have already provided vcall
89 /* The vtable index of the next vcall or vbase offset. */
91 /* Nonzero if we are building the initializer for the primary
94 /* Nonzero if we are building the initializer for a construction
97 /* True when adding vcall offset entries to the vtable. False when
98 merely computing the indices. */
99 bool generate_vcall_entries;
102 /* The type of a function passed to walk_subobject_offsets. */
103 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
105 /* The stack itself. This is a dynamically resized array. The
106 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
107 static int current_class_stack_size;
108 static class_stack_node_t current_class_stack;
110 /* The size of the largest empty class seen in this translation unit. */
111 static GTY (()) tree sizeof_biggest_empty_class;
113 /* An array of all local classes present in this translation unit, in
114 declaration order. */
115 VEC(tree,gc) *local_classes;
117 static tree get_vfield_name (tree);
118 static void finish_struct_anon (tree);
119 static tree get_vtable_name (tree);
120 static tree get_basefndecls (tree, tree);
121 static int build_primary_vtable (tree, tree);
122 static int build_secondary_vtable (tree);
123 static void finish_vtbls (tree);
124 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
125 static void finish_struct_bits (tree);
126 static int alter_access (tree, tree, tree);
127 static void handle_using_decl (tree, tree);
128 static tree dfs_modify_vtables (tree, void *);
129 static tree modify_all_vtables (tree, tree);
130 static void determine_primary_bases (tree);
131 static void finish_struct_methods (tree);
132 static void maybe_warn_about_overly_private_class (tree);
133 static int method_name_cmp (const void *, const void *);
134 static int resort_method_name_cmp (const void *, const void *);
135 static void add_implicitly_declared_members (tree, int, int);
136 static tree fixed_type_or_null (tree, int *, int *);
137 static tree build_simple_base_path (tree expr, tree binfo);
138 static tree build_vtbl_ref_1 (tree, tree);
139 static tree build_vtbl_initializer (tree, tree, tree, tree, int *);
140 static int count_fields (tree);
141 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
142 static 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))
307 /* TARGET_TYPE has been extracted from BINFO, and, is
308 therefore always cv-unqualified. Extract the
309 cv-qualifiers from EXPR so that the expression returned
310 matches the input. */
311 class_type = TREE_TYPE (TREE_TYPE (expr));
313 = cp_build_qualified_type (target_type,
314 cp_type_quals (class_type));
315 return build_nop (build_pointer_type (target_type), expr);
317 null_test = error_mark_node;
320 /* Protect against multiple evaluation if necessary. */
321 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
322 expr = save_expr (expr);
324 /* Now that we've saved expr, build the real null test. */
327 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
328 null_test = fold_build2 (NE_EXPR, boolean_type_node,
332 /* If this is a simple base reference, express it as a COMPONENT_REF. */
333 if (code == PLUS_EXPR && !virtual_access
334 /* We don't build base fields for empty bases, and they aren't very
335 interesting to the optimizers anyway. */
338 expr = build_indirect_ref (expr, NULL);
339 expr = build_simple_base_path (expr, binfo);
341 expr = build_address (expr);
342 target_type = TREE_TYPE (expr);
348 /* Going via virtual base V_BINFO. We need the static offset
349 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
350 V_BINFO. That offset is an entry in D_BINFO's vtable. */
353 if (fixed_type_p < 0 && in_base_initializer)
355 /* In a base member initializer, we cannot rely on the
356 vtable being set up. We have to indirect via the
360 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
361 t = build_pointer_type (t);
362 v_offset = convert (t, current_vtt_parm);
363 v_offset = build_indirect_ref (v_offset, NULL);
366 v_offset = build_vfield_ref (build_indirect_ref (expr, NULL),
367 TREE_TYPE (TREE_TYPE (expr)));
369 v_offset = build2 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
370 v_offset, fold_convert (sizetype, BINFO_VPTR_FIELD (v_binfo)));
371 v_offset = build1 (NOP_EXPR,
372 build_pointer_type (ptrdiff_type_node),
374 v_offset = build_indirect_ref (v_offset, NULL);
375 TREE_CONSTANT (v_offset) = 1;
376 TREE_INVARIANT (v_offset) = 1;
378 offset = convert_to_integer (ptrdiff_type_node,
380 BINFO_OFFSET (v_binfo)));
382 if (!integer_zerop (offset))
383 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
385 if (fixed_type_p < 0)
386 /* Negative fixed_type_p means this is a constructor or destructor;
387 virtual base layout is fixed in in-charge [cd]tors, but not in
389 offset = build3 (COND_EXPR, ptrdiff_type_node,
390 build2 (EQ_EXPR, boolean_type_node,
391 current_in_charge_parm, integer_zero_node),
393 convert_to_integer (ptrdiff_type_node,
394 BINFO_OFFSET (binfo)));
399 target_type = cp_build_qualified_type
400 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
401 ptr_target_type = build_pointer_type (target_type);
403 target_type = ptr_target_type;
405 expr = build1 (NOP_EXPR, ptr_target_type, expr);
407 if (!integer_zerop (offset))
409 offset = fold_convert (sizetype, offset);
410 if (code == MINUS_EXPR)
411 offset = fold_build1 (NEGATE_EXPR, sizetype, offset);
412 expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
418 expr = build_indirect_ref (expr, NULL);
422 expr = fold_build3 (COND_EXPR, target_type, null_test, expr,
423 fold_build1 (NOP_EXPR, target_type,
429 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
430 Perform a derived-to-base conversion by recursively building up a
431 sequence of COMPONENT_REFs to the appropriate base fields. */
434 build_simple_base_path (tree expr, tree binfo)
436 tree type = BINFO_TYPE (binfo);
437 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
440 if (d_binfo == NULL_TREE)
444 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
446 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
447 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
448 an lvalue in the front end; only _DECLs and _REFs are lvalues
450 temp = unary_complex_lvalue (ADDR_EXPR, expr);
452 expr = build_indirect_ref (temp, NULL);
458 expr = build_simple_base_path (expr, d_binfo);
460 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
461 field; field = TREE_CHAIN (field))
462 /* Is this the base field created by build_base_field? */
463 if (TREE_CODE (field) == FIELD_DECL
464 && DECL_FIELD_IS_BASE (field)
465 && TREE_TYPE (field) == type)
467 /* We don't use build_class_member_access_expr here, as that
468 has unnecessary checks, and more importantly results in
469 recursive calls to dfs_walk_once. */
470 int type_quals = cp_type_quals (TREE_TYPE (expr));
472 expr = build3 (COMPONENT_REF,
473 cp_build_qualified_type (type, type_quals),
474 expr, field, NULL_TREE);
475 expr = fold_if_not_in_template (expr);
477 /* Mark the expression const or volatile, as appropriate.
478 Even though we've dealt with the type above, we still have
479 to mark the expression itself. */
480 if (type_quals & TYPE_QUAL_CONST)
481 TREE_READONLY (expr) = 1;
482 if (type_quals & TYPE_QUAL_VOLATILE)
483 TREE_THIS_VOLATILE (expr) = 1;
488 /* Didn't find the base field?!? */
492 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
493 type is a class type or a pointer to a class type. In the former
494 case, TYPE is also a class type; in the latter it is another
495 pointer type. If CHECK_ACCESS is true, an error message is emitted
496 if TYPE is inaccessible. If OBJECT has pointer type, the value is
497 assumed to be non-NULL. */
500 convert_to_base (tree object, tree type, bool check_access, bool nonnull)
505 if (TYPE_PTR_P (TREE_TYPE (object)))
507 object_type = TREE_TYPE (TREE_TYPE (object));
508 type = TREE_TYPE (type);
511 object_type = TREE_TYPE (object);
513 binfo = lookup_base (object_type, type,
514 check_access ? ba_check : ba_unique,
516 if (!binfo || binfo == error_mark_node)
517 return error_mark_node;
519 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
522 /* EXPR is an expression with unqualified class type. BASE is a base
523 binfo of that class type. Returns EXPR, converted to the BASE
524 type. This function assumes that EXPR is the most derived class;
525 therefore virtual bases can be found at their static offsets. */
528 convert_to_base_statically (tree expr, tree base)
532 expr_type = TREE_TYPE (expr);
533 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
537 pointer_type = build_pointer_type (expr_type);
539 /* We use fold_build2 and fold_convert below to simplify the trees
540 provided to the optimizers. It is not safe to call these functions
541 when processing a template because they do not handle C++-specific
543 gcc_assert (!processing_template_decl);
544 expr = build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1);
545 if (!integer_zerop (BINFO_OFFSET (base)))
546 expr = fold_build2 (POINTER_PLUS_EXPR, pointer_type, expr,
547 fold_convert (sizetype, BINFO_OFFSET (base)));
548 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
549 expr = build_fold_indirect_ref (expr);
557 build_vfield_ref (tree datum, tree type)
559 tree vfield, vcontext;
561 if (datum == error_mark_node)
562 return error_mark_node;
564 /* First, convert to the requested type. */
565 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
566 datum = convert_to_base (datum, type, /*check_access=*/false,
569 /* Second, the requested type may not be the owner of its own vptr.
570 If not, convert to the base class that owns it. We cannot use
571 convert_to_base here, because VCONTEXT may appear more than once
572 in the inheritance hierarchy of TYPE, and thus direct conversion
573 between the types may be ambiguous. Following the path back up
574 one step at a time via primary bases avoids the problem. */
575 vfield = TYPE_VFIELD (type);
576 vcontext = DECL_CONTEXT (vfield);
577 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
579 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
580 type = TREE_TYPE (datum);
583 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
586 /* Given an object INSTANCE, return an expression which yields the
587 vtable element corresponding to INDEX. There are many special
588 cases for INSTANCE which we take care of here, mainly to avoid
589 creating extra tree nodes when we don't have to. */
592 build_vtbl_ref_1 (tree instance, tree idx)
595 tree vtbl = NULL_TREE;
597 /* Try to figure out what a reference refers to, and
598 access its virtual function table directly. */
601 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
603 tree basetype = non_reference (TREE_TYPE (instance));
605 if (fixed_type && !cdtorp)
607 tree binfo = lookup_base (fixed_type, basetype,
608 ba_unique | ba_quiet, NULL);
610 vtbl = unshare_expr (BINFO_VTABLE (binfo));
614 vtbl = build_vfield_ref (instance, basetype);
616 assemble_external (vtbl);
618 aref = build_array_ref (vtbl, idx);
619 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
620 TREE_INVARIANT (aref) = TREE_CONSTANT (aref);
626 build_vtbl_ref (tree instance, tree idx)
628 tree aref = build_vtbl_ref_1 (instance, idx);
633 /* Given a stable object pointer INSTANCE_PTR, return an expression which
634 yields a function pointer corresponding to vtable element INDEX. */
637 build_vfn_ref (tree instance_ptr, tree idx)
641 aref = build_vtbl_ref_1 (build_indirect_ref (instance_ptr, 0), idx);
643 /* When using function descriptors, the address of the
644 vtable entry is treated as a function pointer. */
645 if (TARGET_VTABLE_USES_DESCRIPTORS)
646 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
647 build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1));
649 /* Remember this as a method reference, for later devirtualization. */
650 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
655 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
656 for the given TYPE. */
659 get_vtable_name (tree type)
661 return mangle_vtbl_for_type (type);
664 /* DECL is an entity associated with TYPE, like a virtual table or an
665 implicitly generated constructor. Determine whether or not DECL
666 should have external or internal linkage at the object file
667 level. This routine does not deal with COMDAT linkage and other
668 similar complexities; it simply sets TREE_PUBLIC if it possible for
669 entities in other translation units to contain copies of DECL, in
673 set_linkage_according_to_type (tree type, tree decl)
675 /* If TYPE involves a local class in a function with internal
676 linkage, then DECL should have internal linkage too. Other local
677 classes have no linkage -- but if their containing functions
678 have external linkage, it makes sense for DECL to have external
679 linkage too. That will allow template definitions to be merged,
681 if (no_linkage_check (type, /*relaxed_p=*/true))
683 TREE_PUBLIC (decl) = 0;
684 DECL_INTERFACE_KNOWN (decl) = 1;
687 TREE_PUBLIC (decl) = 1;
690 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
691 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
692 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
695 build_vtable (tree class_type, tree name, tree vtable_type)
699 decl = build_lang_decl (VAR_DECL, name, vtable_type);
700 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
701 now to avoid confusion in mangle_decl. */
702 SET_DECL_ASSEMBLER_NAME (decl, name);
703 DECL_CONTEXT (decl) = class_type;
704 DECL_ARTIFICIAL (decl) = 1;
705 TREE_STATIC (decl) = 1;
706 TREE_READONLY (decl) = 1;
707 DECL_VIRTUAL_P (decl) = 1;
708 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
709 DECL_VTABLE_OR_VTT_P (decl) = 1;
710 /* At one time the vtable info was grabbed 2 words at a time. This
711 fails on sparc unless you have 8-byte alignment. (tiemann) */
712 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
714 set_linkage_according_to_type (class_type, decl);
715 /* The vtable has not been defined -- yet. */
716 DECL_EXTERNAL (decl) = 1;
717 DECL_NOT_REALLY_EXTERN (decl) = 1;
719 /* Mark the VAR_DECL node representing the vtable itself as a
720 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
721 is rather important that such things be ignored because any
722 effort to actually generate DWARF for them will run into
723 trouble when/if we encounter code like:
726 struct S { virtual void member (); };
728 because the artificial declaration of the vtable itself (as
729 manufactured by the g++ front end) will say that the vtable is
730 a static member of `S' but only *after* the debug output for
731 the definition of `S' has already been output. This causes
732 grief because the DWARF entry for the definition of the vtable
733 will try to refer back to an earlier *declaration* of the
734 vtable as a static member of `S' and there won't be one. We
735 might be able to arrange to have the "vtable static member"
736 attached to the member list for `S' before the debug info for
737 `S' get written (which would solve the problem) but that would
738 require more intrusive changes to the g++ front end. */
739 DECL_IGNORED_P (decl) = 1;
744 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
745 or even complete. If this does not exist, create it. If COMPLETE is
746 nonzero, then complete the definition of it -- that will render it
747 impossible to actually build the vtable, but is useful to get at those
748 which are known to exist in the runtime. */
751 get_vtable_decl (tree type, int complete)
755 if (CLASSTYPE_VTABLES (type))
756 return CLASSTYPE_VTABLES (type);
758 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
759 CLASSTYPE_VTABLES (type) = decl;
763 DECL_EXTERNAL (decl) = 1;
764 finish_decl (decl, NULL_TREE, NULL_TREE);
770 /* Build the primary virtual function table for TYPE. If BINFO is
771 non-NULL, build the vtable starting with the initial approximation
772 that it is the same as the one which is the head of the association
773 list. Returns a nonzero value if a new vtable is actually
777 build_primary_vtable (tree binfo, tree type)
782 decl = get_vtable_decl (type, /*complete=*/0);
786 if (BINFO_NEW_VTABLE_MARKED (binfo))
787 /* We have already created a vtable for this base, so there's
788 no need to do it again. */
791 virtuals = copy_list (BINFO_VIRTUALS (binfo));
792 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
793 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
794 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
798 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
799 virtuals = NULL_TREE;
802 #ifdef GATHER_STATISTICS
804 n_vtable_elems += list_length (virtuals);
807 /* Initialize the association list for this type, based
808 on our first approximation. */
809 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
810 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
811 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
815 /* Give BINFO a new virtual function table which is initialized
816 with a skeleton-copy of its original initialization. The only
817 entry that changes is the `delta' entry, so we can really
818 share a lot of structure.
820 FOR_TYPE is the most derived type which caused this table to
823 Returns nonzero if we haven't met BINFO before.
825 The order in which vtables are built (by calling this function) for
826 an object must remain the same, otherwise a binary incompatibility
830 build_secondary_vtable (tree binfo)
832 if (BINFO_NEW_VTABLE_MARKED (binfo))
833 /* We already created a vtable for this base. There's no need to
837 /* Remember that we've created a vtable for this BINFO, so that we
838 don't try to do so again. */
839 SET_BINFO_NEW_VTABLE_MARKED (binfo);
841 /* Make fresh virtual list, so we can smash it later. */
842 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
844 /* Secondary vtables are laid out as part of the same structure as
845 the primary vtable. */
846 BINFO_VTABLE (binfo) = NULL_TREE;
850 /* Create a new vtable for BINFO which is the hierarchy dominated by
851 T. Return nonzero if we actually created a new vtable. */
854 make_new_vtable (tree t, tree binfo)
856 if (binfo == TYPE_BINFO (t))
857 /* In this case, it is *type*'s vtable we are modifying. We start
858 with the approximation that its vtable is that of the
859 immediate base class. */
860 return build_primary_vtable (binfo, t);
862 /* This is our very own copy of `basetype' to play with. Later,
863 we will fill in all the virtual functions that override the
864 virtual functions in these base classes which are not defined
865 by the current type. */
866 return build_secondary_vtable (binfo);
869 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
870 (which is in the hierarchy dominated by T) list FNDECL as its
871 BV_FN. DELTA is the required constant adjustment from the `this'
872 pointer where the vtable entry appears to the `this' required when
873 the function is actually called. */
876 modify_vtable_entry (tree t,
886 if (fndecl != BV_FN (v)
887 || !tree_int_cst_equal (delta, BV_DELTA (v)))
889 /* We need a new vtable for BINFO. */
890 if (make_new_vtable (t, binfo))
892 /* If we really did make a new vtable, we also made a copy
893 of the BINFO_VIRTUALS list. Now, we have to find the
894 corresponding entry in that list. */
895 *virtuals = BINFO_VIRTUALS (binfo);
896 while (BV_FN (*virtuals) != BV_FN (v))
897 *virtuals = TREE_CHAIN (*virtuals);
901 BV_DELTA (v) = delta;
902 BV_VCALL_INDEX (v) = NULL_TREE;
908 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
909 the USING_DECL naming METHOD. Returns true if the method could be
910 added to the method vec. */
913 add_method (tree type, tree method, tree using_decl)
917 bool template_conv_p = false;
919 VEC(tree,gc) *method_vec;
921 bool insert_p = false;
925 if (method == error_mark_node)
928 complete_p = COMPLETE_TYPE_P (type);
929 conv_p = DECL_CONV_FN_P (method);
931 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
932 && DECL_TEMPLATE_CONV_FN_P (method));
934 method_vec = CLASSTYPE_METHOD_VEC (type);
937 /* Make a new method vector. We start with 8 entries. We must
938 allocate at least two (for constructors and destructors), and
939 we're going to end up with an assignment operator at some
941 method_vec = VEC_alloc (tree, gc, 8);
942 /* Create slots for constructors and destructors. */
943 VEC_quick_push (tree, method_vec, NULL_TREE);
944 VEC_quick_push (tree, method_vec, NULL_TREE);
945 CLASSTYPE_METHOD_VEC (type) = method_vec;
948 /* Maintain TYPE_HAS_CONSTRUCTOR, etc. */
949 grok_special_member_properties (method);
951 /* Constructors and destructors go in special slots. */
952 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
953 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
954 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
956 slot = CLASSTYPE_DESTRUCTOR_SLOT;
958 if (TYPE_FOR_JAVA (type))
960 if (!DECL_ARTIFICIAL (method))
961 error ("Java class %qT cannot have a destructor", type);
962 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
963 error ("Java class %qT cannot have an implicit non-trivial "
973 /* See if we already have an entry with this name. */
974 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
975 VEC_iterate (tree, method_vec, slot, m);
981 if (TREE_CODE (m) == TEMPLATE_DECL
982 && DECL_TEMPLATE_CONV_FN_P (m))
986 if (conv_p && !DECL_CONV_FN_P (m))
988 if (DECL_NAME (m) == DECL_NAME (method))
994 && !DECL_CONV_FN_P (m)
995 && DECL_NAME (m) > DECL_NAME (method))
999 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1001 /* Check to see if we've already got this method. */
1002 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1004 tree fn = OVL_CURRENT (fns);
1010 if (TREE_CODE (fn) != TREE_CODE (method))
1013 /* [over.load] Member function declarations with the
1014 same name and the same parameter types cannot be
1015 overloaded if any of them is a static member
1016 function declaration.
1018 [namespace.udecl] When a using-declaration brings names
1019 from a base class into a derived class scope, member
1020 functions in the derived class override and/or hide member
1021 functions with the same name and parameter types in a base
1022 class (rather than conflicting). */
1023 fn_type = TREE_TYPE (fn);
1024 method_type = TREE_TYPE (method);
1025 parms1 = TYPE_ARG_TYPES (fn_type);
1026 parms2 = TYPE_ARG_TYPES (method_type);
1028 /* Compare the quals on the 'this' parm. Don't compare
1029 the whole types, as used functions are treated as
1030 coming from the using class in overload resolution. */
1031 if (! DECL_STATIC_FUNCTION_P (fn)
1032 && ! DECL_STATIC_FUNCTION_P (method)
1033 && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
1034 != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
1037 /* For templates, the return type and template parameters
1038 must be identical. */
1039 if (TREE_CODE (fn) == TEMPLATE_DECL
1040 && (!same_type_p (TREE_TYPE (fn_type),
1041 TREE_TYPE (method_type))
1042 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1043 DECL_TEMPLATE_PARMS (method))))
1046 if (! DECL_STATIC_FUNCTION_P (fn))
1047 parms1 = TREE_CHAIN (parms1);
1048 if (! DECL_STATIC_FUNCTION_P (method))
1049 parms2 = TREE_CHAIN (parms2);
1051 if (compparms (parms1, parms2)
1052 && (!DECL_CONV_FN_P (fn)
1053 || same_type_p (TREE_TYPE (fn_type),
1054 TREE_TYPE (method_type))))
1058 if (DECL_CONTEXT (fn) == type)
1059 /* Defer to the local function. */
1061 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1062 error ("repeated using declaration %q+D", using_decl);
1064 error ("using declaration %q+D conflicts with a previous using declaration",
1069 error ("%q+#D cannot be overloaded", method);
1070 error ("with %q+#D", fn);
1073 /* We don't call duplicate_decls here to merge the
1074 declarations because that will confuse things if the
1075 methods have inline definitions. In particular, we
1076 will crash while processing the definitions. */
1081 /* A class should never have more than one destructor. */
1082 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1085 /* Add the new binding. */
1086 overload = build_overload (method, current_fns);
1089 TYPE_HAS_CONVERSION (type) = 1;
1090 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1091 push_class_level_binding (DECL_NAME (method), overload);
1097 /* We only expect to add few methods in the COMPLETE_P case, so
1098 just make room for one more method in that case. */
1100 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1102 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1104 CLASSTYPE_METHOD_VEC (type) = method_vec;
1105 if (slot == VEC_length (tree, method_vec))
1106 VEC_quick_push (tree, method_vec, overload);
1108 VEC_quick_insert (tree, method_vec, slot, overload);
1111 /* Replace the current slot. */
1112 VEC_replace (tree, method_vec, slot, overload);
1116 /* Subroutines of finish_struct. */
1118 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1119 legit, otherwise return 0. */
1122 alter_access (tree t, tree fdecl, tree access)
1126 if (!DECL_LANG_SPECIFIC (fdecl))
1127 retrofit_lang_decl (fdecl);
1129 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1131 elem = purpose_member (t, DECL_ACCESS (fdecl));
1134 if (TREE_VALUE (elem) != access)
1136 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1137 error ("conflicting access specifications for method"
1138 " %q+D, ignored", TREE_TYPE (fdecl));
1140 error ("conflicting access specifications for field %qE, ignored",
1145 /* They're changing the access to the same thing they changed
1146 it to before. That's OK. */
1152 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1153 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1159 /* Process the USING_DECL, which is a member of T. */
1162 handle_using_decl (tree using_decl, tree t)
1164 tree decl = USING_DECL_DECLS (using_decl);
1165 tree name = DECL_NAME (using_decl);
1167 = TREE_PRIVATE (using_decl) ? access_private_node
1168 : TREE_PROTECTED (using_decl) ? access_protected_node
1169 : access_public_node;
1170 tree flist = NULL_TREE;
1173 gcc_assert (!processing_template_decl && decl);
1175 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1178 if (is_overloaded_fn (old_value))
1179 old_value = OVL_CURRENT (old_value);
1181 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1184 old_value = NULL_TREE;
1187 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1189 if (is_overloaded_fn (decl))
1194 else if (is_overloaded_fn (old_value))
1197 /* It's OK to use functions from a base when there are functions with
1198 the same name already present in the current class. */;
1201 error ("%q+D invalid in %q#T", using_decl, t);
1202 error (" because of local method %q+#D with same name",
1203 OVL_CURRENT (old_value));
1207 else if (!DECL_ARTIFICIAL (old_value))
1209 error ("%q+D invalid in %q#T", using_decl, t);
1210 error (" because of local member %q+#D with same name", old_value);
1214 /* Make type T see field decl FDECL with access ACCESS. */
1216 for (; flist; flist = OVL_NEXT (flist))
1218 add_method (t, OVL_CURRENT (flist), using_decl);
1219 alter_access (t, OVL_CURRENT (flist), access);
1222 alter_access (t, decl, access);
1225 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1226 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1227 properties of the bases. */
1230 check_bases (tree t,
1231 int* cant_have_const_ctor_p,
1232 int* no_const_asn_ref_p)
1235 int seen_non_virtual_nearly_empty_base_p;
1239 seen_non_virtual_nearly_empty_base_p = 0;
1241 for (binfo = TYPE_BINFO (t), i = 0;
1242 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1244 tree basetype = TREE_TYPE (base_binfo);
1246 gcc_assert (COMPLETE_TYPE_P (basetype));
1248 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1249 here because the case of virtual functions but non-virtual
1250 dtor is handled in finish_struct_1. */
1251 if (!TYPE_POLYMORPHIC_P (basetype))
1252 warning (OPT_Weffc__,
1253 "base class %q#T has a non-virtual destructor", basetype);
1255 /* If the base class doesn't have copy constructors or
1256 assignment operators that take const references, then the
1257 derived class cannot have such a member automatically
1259 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1260 *cant_have_const_ctor_p = 1;
1261 if (TYPE_HAS_ASSIGN_REF (basetype)
1262 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1263 *no_const_asn_ref_p = 1;
1265 if (BINFO_VIRTUAL_P (base_binfo))
1266 /* A virtual base does not effect nearly emptiness. */
1268 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1270 if (seen_non_virtual_nearly_empty_base_p)
1271 /* And if there is more than one nearly empty base, then the
1272 derived class is not nearly empty either. */
1273 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1275 /* Remember we've seen one. */
1276 seen_non_virtual_nearly_empty_base_p = 1;
1278 else if (!is_empty_class (basetype))
1279 /* If the base class is not empty or nearly empty, then this
1280 class cannot be nearly empty. */
1281 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1283 /* A lot of properties from the bases also apply to the derived
1285 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1286 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1287 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1288 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1289 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1290 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1291 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1292 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1293 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1294 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (basetype);
1298 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1299 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1300 that have had a nearly-empty virtual primary base stolen by some
1301 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1305 determine_primary_bases (tree t)
1308 tree primary = NULL_TREE;
1309 tree type_binfo = TYPE_BINFO (t);
1312 /* Determine the primary bases of our bases. */
1313 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1314 base_binfo = TREE_CHAIN (base_binfo))
1316 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1318 /* See if we're the non-virtual primary of our inheritance
1320 if (!BINFO_VIRTUAL_P (base_binfo))
1322 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1323 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1326 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1327 BINFO_TYPE (parent_primary)))
1328 /* We are the primary binfo. */
1329 BINFO_PRIMARY_P (base_binfo) = 1;
1331 /* Determine if we have a virtual primary base, and mark it so.
1333 if (primary && BINFO_VIRTUAL_P (primary))
1335 tree this_primary = copied_binfo (primary, base_binfo);
1337 if (BINFO_PRIMARY_P (this_primary))
1338 /* Someone already claimed this base. */
1339 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1344 BINFO_PRIMARY_P (this_primary) = 1;
1345 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1347 /* A virtual binfo might have been copied from within
1348 another hierarchy. As we're about to use it as a
1349 primary base, make sure the offsets match. */
1350 delta = size_diffop (convert (ssizetype,
1351 BINFO_OFFSET (base_binfo)),
1353 BINFO_OFFSET (this_primary)));
1355 propagate_binfo_offsets (this_primary, delta);
1360 /* First look for a dynamic direct non-virtual base. */
1361 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1363 tree basetype = BINFO_TYPE (base_binfo);
1365 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1367 primary = base_binfo;
1372 /* A "nearly-empty" virtual base class can be the primary base
1373 class, if no non-virtual polymorphic base can be found. Look for
1374 a nearly-empty virtual dynamic base that is not already a primary
1375 base of something in the hierarchy. If there is no such base,
1376 just pick the first nearly-empty virtual base. */
1378 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1379 base_binfo = TREE_CHAIN (base_binfo))
1380 if (BINFO_VIRTUAL_P (base_binfo)
1381 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1383 if (!BINFO_PRIMARY_P (base_binfo))
1385 /* Found one that is not primary. */
1386 primary = base_binfo;
1390 /* Remember the first candidate. */
1391 primary = base_binfo;
1395 /* If we've got a primary base, use it. */
1398 tree basetype = BINFO_TYPE (primary);
1400 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1401 if (BINFO_PRIMARY_P (primary))
1402 /* We are stealing a primary base. */
1403 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1404 BINFO_PRIMARY_P (primary) = 1;
1405 if (BINFO_VIRTUAL_P (primary))
1409 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1410 /* A virtual binfo might have been copied from within
1411 another hierarchy. As we're about to use it as a primary
1412 base, make sure the offsets match. */
1413 delta = size_diffop (ssize_int (0),
1414 convert (ssizetype, BINFO_OFFSET (primary)));
1416 propagate_binfo_offsets (primary, delta);
1419 primary = TYPE_BINFO (basetype);
1421 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1422 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1423 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1427 /* Set memoizing fields and bits of T (and its variants) for later
1431 finish_struct_bits (tree t)
1435 /* Fix up variants (if any). */
1436 for (variants = TYPE_NEXT_VARIANT (t);
1438 variants = TYPE_NEXT_VARIANT (variants))
1440 /* These fields are in the _TYPE part of the node, not in
1441 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1442 TYPE_HAS_CONSTRUCTOR (variants) = TYPE_HAS_CONSTRUCTOR (t);
1443 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1444 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1445 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1447 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1449 TYPE_BINFO (variants) = TYPE_BINFO (t);
1451 /* Copy whatever these are holding today. */
1452 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1453 TYPE_METHODS (variants) = TYPE_METHODS (t);
1454 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1457 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1458 /* For a class w/o baseclasses, 'finish_struct' has set
1459 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1460 Similarly for a class whose base classes do not have vtables.
1461 When neither of these is true, we might have removed abstract
1462 virtuals (by providing a definition), added some (by declaring
1463 new ones), or redeclared ones from a base class. We need to
1464 recalculate what's really an abstract virtual at this point (by
1465 looking in the vtables). */
1466 get_pure_virtuals (t);
1468 /* If this type has a copy constructor or a destructor, force its
1469 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1470 nonzero. This will cause it to be passed by invisible reference
1471 and prevent it from being returned in a register. */
1472 if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1475 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1476 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1478 TYPE_MODE (variants) = BLKmode;
1479 TREE_ADDRESSABLE (variants) = 1;
1484 /* Issue warnings about T having private constructors, but no friends,
1487 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1488 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1489 non-private static member functions. */
1492 maybe_warn_about_overly_private_class (tree t)
1494 int has_member_fn = 0;
1495 int has_nonprivate_method = 0;
1498 if (!warn_ctor_dtor_privacy
1499 /* If the class has friends, those entities might create and
1500 access instances, so we should not warn. */
1501 || (CLASSTYPE_FRIEND_CLASSES (t)
1502 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1503 /* We will have warned when the template was declared; there's
1504 no need to warn on every instantiation. */
1505 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1506 /* There's no reason to even consider warning about this
1510 /* We only issue one warning, if more than one applies, because
1511 otherwise, on code like:
1514 // Oops - forgot `public:'
1520 we warn several times about essentially the same problem. */
1522 /* Check to see if all (non-constructor, non-destructor) member
1523 functions are private. (Since there are no friends or
1524 non-private statics, we can't ever call any of the private member
1526 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1527 /* We're not interested in compiler-generated methods; they don't
1528 provide any way to call private members. */
1529 if (!DECL_ARTIFICIAL (fn))
1531 if (!TREE_PRIVATE (fn))
1533 if (DECL_STATIC_FUNCTION_P (fn))
1534 /* A non-private static member function is just like a
1535 friend; it can create and invoke private member
1536 functions, and be accessed without a class
1540 has_nonprivate_method = 1;
1541 /* Keep searching for a static member function. */
1543 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1547 if (!has_nonprivate_method && has_member_fn)
1549 /* There are no non-private methods, and there's at least one
1550 private member function that isn't a constructor or
1551 destructor. (If all the private members are
1552 constructors/destructors we want to use the code below that
1553 issues error messages specifically referring to
1554 constructors/destructors.) */
1556 tree binfo = TYPE_BINFO (t);
1558 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1559 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1561 has_nonprivate_method = 1;
1564 if (!has_nonprivate_method)
1566 warning (OPT_Wctor_dtor_privacy,
1567 "all member functions in class %qT are private", t);
1572 /* Even if some of the member functions are non-private, the class
1573 won't be useful for much if all the constructors or destructors
1574 are private: such an object can never be created or destroyed. */
1575 fn = CLASSTYPE_DESTRUCTORS (t);
1576 if (fn && TREE_PRIVATE (fn))
1578 warning (OPT_Wctor_dtor_privacy,
1579 "%q#T only defines a private destructor and has no friends",
1584 if (TYPE_HAS_CONSTRUCTOR (t)
1585 /* Implicitly generated constructors are always public. */
1586 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1587 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1589 int nonprivate_ctor = 0;
1591 /* If a non-template class does not define a copy
1592 constructor, one is defined for it, enabling it to avoid
1593 this warning. For a template class, this does not
1594 happen, and so we would normally get a warning on:
1596 template <class T> class C { private: C(); };
1598 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1599 complete non-template or fully instantiated classes have this
1601 if (!TYPE_HAS_INIT_REF (t))
1602 nonprivate_ctor = 1;
1604 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1606 tree ctor = OVL_CURRENT (fn);
1607 /* Ideally, we wouldn't count copy constructors (or, in
1608 fact, any constructor that takes an argument of the
1609 class type as a parameter) because such things cannot
1610 be used to construct an instance of the class unless
1611 you already have one. But, for now at least, we're
1613 if (! TREE_PRIVATE (ctor))
1615 nonprivate_ctor = 1;
1620 if (nonprivate_ctor == 0)
1622 warning (OPT_Wctor_dtor_privacy,
1623 "%q#T only defines private constructors and has no friends",
1631 gt_pointer_operator new_value;
1635 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1638 method_name_cmp (const void* m1_p, const void* m2_p)
1640 const tree *const m1 = (const tree *) m1_p;
1641 const tree *const m2 = (const tree *) m2_p;
1643 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1645 if (*m1 == NULL_TREE)
1647 if (*m2 == NULL_TREE)
1649 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1654 /* This routine compares two fields like method_name_cmp but using the
1655 pointer operator in resort_field_decl_data. */
1658 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1660 const tree *const m1 = (const tree *) m1_p;
1661 const tree *const m2 = (const tree *) m2_p;
1662 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1664 if (*m1 == NULL_TREE)
1666 if (*m2 == NULL_TREE)
1669 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1670 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1671 resort_data.new_value (&d1, resort_data.cookie);
1672 resort_data.new_value (&d2, resort_data.cookie);
1679 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1682 resort_type_method_vec (void* obj,
1683 void* orig_obj ATTRIBUTE_UNUSED ,
1684 gt_pointer_operator new_value,
1687 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1688 int len = VEC_length (tree, method_vec);
1692 /* The type conversion ops have to live at the front of the vec, so we
1694 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1695 VEC_iterate (tree, method_vec, slot, fn);
1697 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1702 resort_data.new_value = new_value;
1703 resort_data.cookie = cookie;
1704 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1705 resort_method_name_cmp);
1709 /* Warn about duplicate methods in fn_fields.
1711 Sort methods that are not special (i.e., constructors, destructors,
1712 and type conversion operators) so that we can find them faster in
1716 finish_struct_methods (tree t)
1719 VEC(tree,gc) *method_vec;
1722 method_vec = CLASSTYPE_METHOD_VEC (t);
1726 len = VEC_length (tree, method_vec);
1728 /* Clear DECL_IN_AGGR_P for all functions. */
1729 for (fn_fields = TYPE_METHODS (t); fn_fields;
1730 fn_fields = TREE_CHAIN (fn_fields))
1731 DECL_IN_AGGR_P (fn_fields) = 0;
1733 /* Issue warnings about private constructors and such. If there are
1734 no methods, then some public defaults are generated. */
1735 maybe_warn_about_overly_private_class (t);
1737 /* The type conversion ops have to live at the front of the vec, so we
1739 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1740 VEC_iterate (tree, method_vec, slot, fn_fields);
1742 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1745 qsort (VEC_address (tree, method_vec) + slot,
1746 len-slot, sizeof (tree), method_name_cmp);
1749 /* Make BINFO's vtable have N entries, including RTTI entries,
1750 vbase and vcall offsets, etc. Set its type and call the back end
1754 layout_vtable_decl (tree binfo, int n)
1759 atype = build_cplus_array_type (vtable_entry_type,
1760 build_index_type (size_int (n - 1)));
1761 layout_type (atype);
1763 /* We may have to grow the vtable. */
1764 vtable = get_vtbl_decl_for_binfo (binfo);
1765 if (!same_type_p (TREE_TYPE (vtable), atype))
1767 TREE_TYPE (vtable) = atype;
1768 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1769 layout_decl (vtable, 0);
1773 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1774 have the same signature. */
1777 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1779 /* One destructor overrides another if they are the same kind of
1781 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1782 && special_function_p (base_fndecl) == special_function_p (fndecl))
1784 /* But a non-destructor never overrides a destructor, nor vice
1785 versa, nor do different kinds of destructors override
1786 one-another. For example, a complete object destructor does not
1787 override a deleting destructor. */
1788 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1791 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1792 || (DECL_CONV_FN_P (fndecl)
1793 && DECL_CONV_FN_P (base_fndecl)
1794 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1795 DECL_CONV_FN_TYPE (base_fndecl))))
1797 tree types, base_types;
1798 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1799 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1800 if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1801 == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1802 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1808 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1812 base_derived_from (tree derived, tree base)
1816 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1818 if (probe == derived)
1820 else if (BINFO_VIRTUAL_P (probe))
1821 /* If we meet a virtual base, we can't follow the inheritance
1822 any more. See if the complete type of DERIVED contains
1823 such a virtual base. */
1824 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1830 typedef struct find_final_overrider_data_s {
1831 /* The function for which we are trying to find a final overrider. */
1833 /* The base class in which the function was declared. */
1834 tree declaring_base;
1835 /* The candidate overriders. */
1837 /* Path to most derived. */
1838 VEC(tree,heap) *path;
1839 } find_final_overrider_data;
1841 /* Add the overrider along the current path to FFOD->CANDIDATES.
1842 Returns true if an overrider was found; false otherwise. */
1845 dfs_find_final_overrider_1 (tree binfo,
1846 find_final_overrider_data *ffod,
1851 /* If BINFO is not the most derived type, try a more derived class.
1852 A definition there will overrider a definition here. */
1856 if (dfs_find_final_overrider_1
1857 (VEC_index (tree, ffod->path, depth), ffod, depth))
1861 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1864 tree *candidate = &ffod->candidates;
1866 /* Remove any candidates overridden by this new function. */
1869 /* If *CANDIDATE overrides METHOD, then METHOD
1870 cannot override anything else on the list. */
1871 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1873 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1874 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1875 *candidate = TREE_CHAIN (*candidate);
1877 candidate = &TREE_CHAIN (*candidate);
1880 /* Add the new function. */
1881 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1888 /* Called from find_final_overrider via dfs_walk. */
1891 dfs_find_final_overrider_pre (tree binfo, void *data)
1893 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1895 if (binfo == ffod->declaring_base)
1896 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1897 VEC_safe_push (tree, heap, ffod->path, binfo);
1903 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1905 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1906 VEC_pop (tree, ffod->path);
1911 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1912 FN and whose TREE_VALUE is the binfo for the base where the
1913 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1914 DERIVED) is the base object in which FN is declared. */
1917 find_final_overrider (tree derived, tree binfo, tree fn)
1919 find_final_overrider_data ffod;
1921 /* Getting this right is a little tricky. This is valid:
1923 struct S { virtual void f (); };
1924 struct T { virtual void f (); };
1925 struct U : public S, public T { };
1927 even though calling `f' in `U' is ambiguous. But,
1929 struct R { virtual void f(); };
1930 struct S : virtual public R { virtual void f (); };
1931 struct T : virtual public R { virtual void f (); };
1932 struct U : public S, public T { };
1934 is not -- there's no way to decide whether to put `S::f' or
1935 `T::f' in the vtable for `R'.
1937 The solution is to look at all paths to BINFO. If we find
1938 different overriders along any two, then there is a problem. */
1939 if (DECL_THUNK_P (fn))
1940 fn = THUNK_TARGET (fn);
1942 /* Determine the depth of the hierarchy. */
1944 ffod.declaring_base = binfo;
1945 ffod.candidates = NULL_TREE;
1946 ffod.path = VEC_alloc (tree, heap, 30);
1948 dfs_walk_all (derived, dfs_find_final_overrider_pre,
1949 dfs_find_final_overrider_post, &ffod);
1951 VEC_free (tree, heap, ffod.path);
1953 /* If there was no winner, issue an error message. */
1954 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
1955 return error_mark_node;
1957 return ffod.candidates;
1960 /* Return the index of the vcall offset for FN when TYPE is used as a
1964 get_vcall_index (tree fn, tree type)
1966 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
1970 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
1971 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
1972 || same_signature_p (fn, p->purpose))
1975 /* There should always be an appropriate index. */
1979 /* Update an entry in the vtable for BINFO, which is in the hierarchy
1980 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
1981 corresponding position in the BINFO_VIRTUALS list. */
1984 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
1992 tree overrider_fn, overrider_target;
1993 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
1994 tree over_return, base_return;
1997 /* Find the nearest primary base (possibly binfo itself) which defines
1998 this function; this is the class the caller will convert to when
1999 calling FN through BINFO. */
2000 for (b = binfo; ; b = get_primary_binfo (b))
2003 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2006 /* The nearest definition is from a lost primary. */
2007 if (BINFO_LOST_PRIMARY_P (b))
2012 /* Find the final overrider. */
2013 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2014 if (overrider == error_mark_node)
2016 error ("no unique final overrider for %qD in %qT", target_fn, t);
2019 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2021 /* Check for adjusting covariant return types. */
2022 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2023 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2025 if (POINTER_TYPE_P (over_return)
2026 && TREE_CODE (over_return) == TREE_CODE (base_return)
2027 && CLASS_TYPE_P (TREE_TYPE (over_return))
2028 && CLASS_TYPE_P (TREE_TYPE (base_return))
2029 /* If the overrider is invalid, don't even try. */
2030 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2032 /* If FN is a covariant thunk, we must figure out the adjustment
2033 to the final base FN was converting to. As OVERRIDER_TARGET might
2034 also be converting to the return type of FN, we have to
2035 combine the two conversions here. */
2036 tree fixed_offset, virtual_offset;
2038 over_return = TREE_TYPE (over_return);
2039 base_return = TREE_TYPE (base_return);
2041 if (DECL_THUNK_P (fn))
2043 gcc_assert (DECL_RESULT_THUNK_P (fn));
2044 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2045 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2048 fixed_offset = virtual_offset = NULL_TREE;
2051 /* Find the equivalent binfo within the return type of the
2052 overriding function. We will want the vbase offset from
2054 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2056 else if (!same_type_ignoring_top_level_qualifiers_p
2057 (over_return, base_return))
2059 /* There was no existing virtual thunk (which takes
2060 precedence). So find the binfo of the base function's
2061 return type within the overriding function's return type.
2062 We cannot call lookup base here, because we're inside a
2063 dfs_walk, and will therefore clobber the BINFO_MARKED
2064 flags. Fortunately we know the covariancy is valid (it
2065 has already been checked), so we can just iterate along
2066 the binfos, which have been chained in inheritance graph
2067 order. Of course it is lame that we have to repeat the
2068 search here anyway -- we should really be caching pieces
2069 of the vtable and avoiding this repeated work. */
2070 tree thunk_binfo, base_binfo;
2072 /* Find the base binfo within the overriding function's
2073 return type. We will always find a thunk_binfo, except
2074 when the covariancy is invalid (which we will have
2075 already diagnosed). */
2076 for (base_binfo = TYPE_BINFO (base_return),
2077 thunk_binfo = TYPE_BINFO (over_return);
2079 thunk_binfo = TREE_CHAIN (thunk_binfo))
2080 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2081 BINFO_TYPE (base_binfo)))
2084 /* See if virtual inheritance is involved. */
2085 for (virtual_offset = thunk_binfo;
2087 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2088 if (BINFO_VIRTUAL_P (virtual_offset))
2092 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2094 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2098 /* We convert via virtual base. Adjust the fixed
2099 offset to be from there. */
2100 offset = size_diffop
2102 (ssizetype, BINFO_OFFSET (virtual_offset)));
2105 /* There was an existing fixed offset, this must be
2106 from the base just converted to, and the base the
2107 FN was thunking to. */
2108 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2110 fixed_offset = offset;
2114 if (fixed_offset || virtual_offset)
2115 /* Replace the overriding function with a covariant thunk. We
2116 will emit the overriding function in its own slot as
2118 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2119 fixed_offset, virtual_offset);
2122 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2123 !DECL_THUNK_P (fn));
2125 /* Assume that we will produce a thunk that convert all the way to
2126 the final overrider, and not to an intermediate virtual base. */
2127 virtual_base = NULL_TREE;
2129 /* See if we can convert to an intermediate virtual base first, and then
2130 use the vcall offset located there to finish the conversion. */
2131 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2133 /* If we find the final overrider, then we can stop
2135 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2136 BINFO_TYPE (TREE_VALUE (overrider))))
2139 /* If we find a virtual base, and we haven't yet found the
2140 overrider, then there is a virtual base between the
2141 declaring base (first_defn) and the final overrider. */
2142 if (BINFO_VIRTUAL_P (b))
2149 if (overrider_fn != overrider_target && !virtual_base)
2151 /* The ABI specifies that a covariant thunk includes a mangling
2152 for a this pointer adjustment. This-adjusting thunks that
2153 override a function from a virtual base have a vcall
2154 adjustment. When the virtual base in question is a primary
2155 virtual base, we know the adjustments are zero, (and in the
2156 non-covariant case, we would not use the thunk).
2157 Unfortunately we didn't notice this could happen, when
2158 designing the ABI and so never mandated that such a covariant
2159 thunk should be emitted. Because we must use the ABI mandated
2160 name, we must continue searching from the binfo where we
2161 found the most recent definition of the function, towards the
2162 primary binfo which first introduced the function into the
2163 vtable. If that enters a virtual base, we must use a vcall
2164 this-adjusting thunk. Bleah! */
2165 tree probe = first_defn;
2167 while ((probe = get_primary_binfo (probe))
2168 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2169 if (BINFO_VIRTUAL_P (probe))
2170 virtual_base = probe;
2173 /* Even if we find a virtual base, the correct delta is
2174 between the overrider and the binfo we're building a vtable
2176 goto virtual_covariant;
2179 /* Compute the constant adjustment to the `this' pointer. The
2180 `this' pointer, when this function is called, will point at BINFO
2181 (or one of its primary bases, which are at the same offset). */
2183 /* The `this' pointer needs to be adjusted from the declaration to
2184 the nearest virtual base. */
2185 delta = size_diffop (convert (ssizetype, BINFO_OFFSET (virtual_base)),
2186 convert (ssizetype, BINFO_OFFSET (first_defn)));
2188 /* If the nearest definition is in a lost primary, we don't need an
2189 entry in our vtable. Except possibly in a constructor vtable,
2190 if we happen to get our primary back. In that case, the offset
2191 will be zero, as it will be a primary base. */
2192 delta = size_zero_node;
2194 /* The `this' pointer needs to be adjusted from pointing to
2195 BINFO to pointing at the base where the final overrider
2198 delta = size_diffop (convert (ssizetype,
2199 BINFO_OFFSET (TREE_VALUE (overrider))),
2200 convert (ssizetype, BINFO_OFFSET (binfo)));
2202 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2205 BV_VCALL_INDEX (*virtuals)
2206 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2208 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2211 /* Called from modify_all_vtables via dfs_walk. */
2214 dfs_modify_vtables (tree binfo, void* data)
2216 tree t = (tree) data;
2221 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2222 /* A base without a vtable needs no modification, and its bases
2223 are uninteresting. */
2224 return dfs_skip_bases;
2226 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2227 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2228 /* Don't do the primary vtable, if it's new. */
2231 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2232 /* There's no need to modify the vtable for a non-virtual primary
2233 base; we're not going to use that vtable anyhow. We do still
2234 need to do this for virtual primary bases, as they could become
2235 non-primary in a construction vtable. */
2238 make_new_vtable (t, binfo);
2240 /* Now, go through each of the virtual functions in the virtual
2241 function table for BINFO. Find the final overrider, and update
2242 the BINFO_VIRTUALS list appropriately. */
2243 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2244 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2246 ix++, virtuals = TREE_CHAIN (virtuals),
2247 old_virtuals = TREE_CHAIN (old_virtuals))
2248 update_vtable_entry_for_fn (t,
2250 BV_FN (old_virtuals),
2256 /* Update all of the primary and secondary vtables for T. Create new
2257 vtables as required, and initialize their RTTI information. Each
2258 of the functions in VIRTUALS is declared in T and may override a
2259 virtual function from a base class; find and modify the appropriate
2260 entries to point to the overriding functions. Returns a list, in
2261 declaration order, of the virtual functions that are declared in T,
2262 but do not appear in the primary base class vtable, and which
2263 should therefore be appended to the end of the vtable for T. */
2266 modify_all_vtables (tree t, tree virtuals)
2268 tree binfo = TYPE_BINFO (t);
2271 /* Update all of the vtables. */
2272 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2274 /* Add virtual functions not already in our primary vtable. These
2275 will be both those introduced by this class, and those overridden
2276 from secondary bases. It does not include virtuals merely
2277 inherited from secondary bases. */
2278 for (fnsp = &virtuals; *fnsp; )
2280 tree fn = TREE_VALUE (*fnsp);
2282 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2283 || DECL_VINDEX (fn) == error_mark_node)
2285 /* We don't need to adjust the `this' pointer when
2286 calling this function. */
2287 BV_DELTA (*fnsp) = integer_zero_node;
2288 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2290 /* This is a function not already in our vtable. Keep it. */
2291 fnsp = &TREE_CHAIN (*fnsp);
2294 /* We've already got an entry for this function. Skip it. */
2295 *fnsp = TREE_CHAIN (*fnsp);
2301 /* Get the base virtual function declarations in T that have the
2305 get_basefndecls (tree name, tree t)
2308 tree base_fndecls = NULL_TREE;
2309 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2312 /* Find virtual functions in T with the indicated NAME. */
2313 i = lookup_fnfields_1 (t, name);
2315 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2317 methods = OVL_NEXT (methods))
2319 tree method = OVL_CURRENT (methods);
2321 if (TREE_CODE (method) == FUNCTION_DECL
2322 && DECL_VINDEX (method))
2323 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2327 return base_fndecls;
2329 for (i = 0; i < n_baseclasses; i++)
2331 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2332 base_fndecls = chainon (get_basefndecls (name, basetype),
2336 return base_fndecls;
2339 /* If this declaration supersedes the declaration of
2340 a method declared virtual in the base class, then
2341 mark this field as being virtual as well. */
2344 check_for_override (tree decl, tree ctype)
2346 if (TREE_CODE (decl) == TEMPLATE_DECL)
2347 /* In [temp.mem] we have:
2349 A specialization of a member function template does not
2350 override a virtual function from a base class. */
2352 if ((DECL_DESTRUCTOR_P (decl)
2353 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2354 || DECL_CONV_FN_P (decl))
2355 && look_for_overrides (ctype, decl)
2356 && !DECL_STATIC_FUNCTION_P (decl))
2357 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2358 the error_mark_node so that we know it is an overriding
2360 DECL_VINDEX (decl) = decl;
2362 if (DECL_VIRTUAL_P (decl))
2364 if (!DECL_VINDEX (decl))
2365 DECL_VINDEX (decl) = error_mark_node;
2366 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2370 /* Warn about hidden virtual functions that are not overridden in t.
2371 We know that constructors and destructors don't apply. */
2374 warn_hidden (tree t)
2376 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2380 /* We go through each separately named virtual function. */
2381 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2382 VEC_iterate (tree, method_vec, i, fns);
2393 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2394 have the same name. Figure out what name that is. */
2395 name = DECL_NAME (OVL_CURRENT (fns));
2396 /* There are no possibly hidden functions yet. */
2397 base_fndecls = NULL_TREE;
2398 /* Iterate through all of the base classes looking for possibly
2399 hidden functions. */
2400 for (binfo = TYPE_BINFO (t), j = 0;
2401 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2403 tree basetype = BINFO_TYPE (base_binfo);
2404 base_fndecls = chainon (get_basefndecls (name, basetype),
2408 /* If there are no functions to hide, continue. */
2412 /* Remove any overridden functions. */
2413 for (fn = fns; fn; fn = OVL_NEXT (fn))
2415 fndecl = OVL_CURRENT (fn);
2416 if (DECL_VINDEX (fndecl))
2418 tree *prev = &base_fndecls;
2421 /* If the method from the base class has the same
2422 signature as the method from the derived class, it
2423 has been overridden. */
2424 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2425 *prev = TREE_CHAIN (*prev);
2427 prev = &TREE_CHAIN (*prev);
2431 /* Now give a warning for all base functions without overriders,
2432 as they are hidden. */
2433 while (base_fndecls)
2435 /* Here we know it is a hider, and no overrider exists. */
2436 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2437 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2438 base_fndecls = TREE_CHAIN (base_fndecls);
2443 /* Check for things that are invalid. There are probably plenty of other
2444 things we should check for also. */
2447 finish_struct_anon (tree t)
2451 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2453 if (TREE_STATIC (field))
2455 if (TREE_CODE (field) != FIELD_DECL)
2458 if (DECL_NAME (field) == NULL_TREE
2459 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2461 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2462 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2463 for (; elt; elt = TREE_CHAIN (elt))
2465 /* We're generally only interested in entities the user
2466 declared, but we also find nested classes by noticing
2467 the TYPE_DECL that we create implicitly. You're
2468 allowed to put one anonymous union inside another,
2469 though, so we explicitly tolerate that. We use
2470 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2471 we also allow unnamed types used for defining fields. */
2472 if (DECL_ARTIFICIAL (elt)
2473 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2474 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2477 if (TREE_CODE (elt) != FIELD_DECL)
2480 pedwarn ("%q+#D invalid; an anonymous union can "
2481 "only have non-static data members", elt);
2483 pedwarn ("%q+#D invalid; an anonymous struct can "
2484 "only have non-static data members", elt);
2488 if (TREE_PRIVATE (elt))
2491 pedwarn ("private member %q+#D in anonymous union", elt);
2493 pedwarn ("private member %q+#D in anonymous struct", elt);
2495 else if (TREE_PROTECTED (elt))
2498 pedwarn ("protected member %q+#D in anonymous union", elt);
2500 pedwarn ("protected member %q+#D in anonymous struct", elt);
2503 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2504 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2510 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2511 will be used later during class template instantiation.
2512 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2513 a non-static member data (FIELD_DECL), a member function
2514 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2515 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2516 When FRIEND_P is nonzero, T is either a friend class
2517 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2518 (FUNCTION_DECL, TEMPLATE_DECL). */
2521 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2523 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2524 if (CLASSTYPE_TEMPLATE_INFO (type))
2525 CLASSTYPE_DECL_LIST (type)
2526 = tree_cons (friend_p ? NULL_TREE : type,
2527 t, CLASSTYPE_DECL_LIST (type));
2530 /* Create default constructors, assignment operators, and so forth for
2531 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2532 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2533 the class cannot have a default constructor, copy constructor
2534 taking a const reference argument, or an assignment operator taking
2535 a const reference, respectively. */
2538 add_implicitly_declared_members (tree t,
2539 int cant_have_const_cctor,
2540 int cant_have_const_assignment)
2543 if (!CLASSTYPE_DESTRUCTORS (t))
2545 /* In general, we create destructors lazily. */
2546 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2547 /* However, if the implicit destructor is non-trivial
2548 destructor, we sometimes have to create it at this point. */
2549 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2553 if (TYPE_FOR_JAVA (t))
2554 /* If this a Java class, any non-trivial destructor is
2555 invalid, even if compiler-generated. Therefore, if the
2556 destructor is non-trivial we create it now. */
2564 /* If the implicit destructor will be virtual, then we must
2565 generate it now because (unfortunately) we do not
2566 generate virtual tables lazily. */
2567 binfo = TYPE_BINFO (t);
2568 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2573 base_type = BINFO_TYPE (base_binfo);
2574 dtor = CLASSTYPE_DESTRUCTORS (base_type);
2575 if (dtor && DECL_VIRTUAL_P (dtor))
2583 /* If we can't get away with being lazy, generate the destructor
2586 lazily_declare_fn (sfk_destructor, t);
2590 /* Default constructor. */
2591 if (! TYPE_HAS_CONSTRUCTOR (t))
2593 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2594 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2597 /* Copy constructor. */
2598 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2600 TYPE_HAS_INIT_REF (t) = 1;
2601 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2602 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2603 TYPE_HAS_CONSTRUCTOR (t) = 1;
2606 /* If there is no assignment operator, one will be created if and
2607 when it is needed. For now, just record whether or not the type
2608 of the parameter to the assignment operator will be a const or
2609 non-const reference. */
2610 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2612 TYPE_HAS_ASSIGN_REF (t) = 1;
2613 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2614 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2618 /* Subroutine of finish_struct_1. Recursively count the number of fields
2619 in TYPE, including anonymous union members. */
2622 count_fields (tree fields)
2626 for (x = fields; x; x = TREE_CHAIN (x))
2628 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2629 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2636 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2637 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2640 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2643 for (x = fields; x; x = TREE_CHAIN (x))
2645 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2646 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2648 field_vec->elts[idx++] = x;
2653 /* FIELD is a bit-field. We are finishing the processing for its
2654 enclosing type. Issue any appropriate messages and set appropriate
2658 check_bitfield_decl (tree field)
2660 tree type = TREE_TYPE (field);
2663 /* Extract the declared width of the bitfield, which has been
2664 temporarily stashed in DECL_INITIAL. */
2665 w = DECL_INITIAL (field);
2666 gcc_assert (w != NULL_TREE);
2667 /* Remove the bit-field width indicator so that the rest of the
2668 compiler does not treat that value as an initializer. */
2669 DECL_INITIAL (field) = NULL_TREE;
2671 /* Detect invalid bit-field type. */
2672 if (!INTEGRAL_TYPE_P (type))
2674 error ("bit-field %q+#D with non-integral type", field);
2675 TREE_TYPE (field) = error_mark_node;
2676 w = error_mark_node;
2680 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2683 /* detect invalid field size. */
2684 w = integral_constant_value (w);
2686 if (TREE_CODE (w) != INTEGER_CST)
2688 error ("bit-field %q+D width not an integer constant", field);
2689 w = error_mark_node;
2691 else if (tree_int_cst_sgn (w) < 0)
2693 error ("negative width in bit-field %q+D", field);
2694 w = error_mark_node;
2696 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2698 error ("zero width for bit-field %q+D", field);
2699 w = error_mark_node;
2701 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2702 && TREE_CODE (type) != ENUMERAL_TYPE
2703 && TREE_CODE (type) != BOOLEAN_TYPE)
2704 warning (0, "width of %q+D exceeds its type", field);
2705 else if (TREE_CODE (type) == ENUMERAL_TYPE
2706 && (0 > compare_tree_int (w,
2707 min_precision (TYPE_MIN_VALUE (type),
2708 TYPE_UNSIGNED (type)))
2709 || 0 > compare_tree_int (w,
2711 (TYPE_MAX_VALUE (type),
2712 TYPE_UNSIGNED (type)))))
2713 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2716 if (w != error_mark_node)
2718 DECL_SIZE (field) = convert (bitsizetype, w);
2719 DECL_BIT_FIELD (field) = 1;
2723 /* Non-bit-fields are aligned for their type. */
2724 DECL_BIT_FIELD (field) = 0;
2725 CLEAR_DECL_C_BIT_FIELD (field);
2729 /* FIELD is a non bit-field. We are finishing the processing for its
2730 enclosing type T. Issue any appropriate messages and set appropriate
2734 check_field_decl (tree field,
2736 int* cant_have_const_ctor,
2737 int* no_const_asn_ref,
2738 int* any_default_members)
2740 tree type = strip_array_types (TREE_TYPE (field));
2742 /* An anonymous union cannot contain any fields which would change
2743 the settings of CANT_HAVE_CONST_CTOR and friends. */
2744 if (ANON_UNION_TYPE_P (type))
2746 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2747 structs. So, we recurse through their fields here. */
2748 else if (ANON_AGGR_TYPE_P (type))
2752 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2753 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2754 check_field_decl (fields, t, cant_have_const_ctor,
2755 no_const_asn_ref, any_default_members);
2757 /* Check members with class type for constructors, destructors,
2759 else if (CLASS_TYPE_P (type))
2761 /* Never let anything with uninheritable virtuals
2762 make it through without complaint. */
2763 abstract_virtuals_error (field, type);
2765 if (TREE_CODE (t) == UNION_TYPE)
2767 if (TYPE_NEEDS_CONSTRUCTING (type))
2768 error ("member %q+#D with constructor not allowed in union",
2770 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2771 error ("member %q+#D with destructor not allowed in union", field);
2772 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2773 error ("member %q+#D with copy assignment operator not allowed in union",
2778 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2779 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2780 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2781 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2782 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2783 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (type);
2786 if (!TYPE_HAS_CONST_INIT_REF (type))
2787 *cant_have_const_ctor = 1;
2789 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2790 *no_const_asn_ref = 1;
2792 if (DECL_INITIAL (field) != NULL_TREE)
2794 /* `build_class_init_list' does not recognize
2796 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2797 error ("multiple fields in union %qT initialized", t);
2798 *any_default_members = 1;
2802 /* Check the data members (both static and non-static), class-scoped
2803 typedefs, etc., appearing in the declaration of T. Issue
2804 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2805 declaration order) of access declarations; each TREE_VALUE in this
2806 list is a USING_DECL.
2808 In addition, set the following flags:
2811 The class is empty, i.e., contains no non-static data members.
2813 CANT_HAVE_CONST_CTOR_P
2814 This class cannot have an implicitly generated copy constructor
2815 taking a const reference.
2817 CANT_HAVE_CONST_ASN_REF
2818 This class cannot have an implicitly generated assignment
2819 operator taking a const reference.
2821 All of these flags should be initialized before calling this
2824 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2825 fields can be added by adding to this chain. */
2828 check_field_decls (tree t, tree *access_decls,
2829 int *cant_have_const_ctor_p,
2830 int *no_const_asn_ref_p)
2835 int any_default_members;
2838 /* Assume there are no access declarations. */
2839 *access_decls = NULL_TREE;
2840 /* Assume this class has no pointer members. */
2841 has_pointers = false;
2842 /* Assume none of the members of this class have default
2844 any_default_members = 0;
2846 for (field = &TYPE_FIELDS (t); *field; field = next)
2849 tree type = TREE_TYPE (x);
2851 next = &TREE_CHAIN (x);
2853 if (TREE_CODE (x) == USING_DECL)
2855 /* Prune the access declaration from the list of fields. */
2856 *field = TREE_CHAIN (x);
2858 /* Save the access declarations for our caller. */
2859 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2861 /* Since we've reset *FIELD there's no reason to skip to the
2867 if (TREE_CODE (x) == TYPE_DECL
2868 || TREE_CODE (x) == TEMPLATE_DECL)
2871 /* If we've gotten this far, it's a data member, possibly static,
2872 or an enumerator. */
2873 DECL_CONTEXT (x) = t;
2875 /* When this goes into scope, it will be a non-local reference. */
2876 DECL_NONLOCAL (x) = 1;
2878 if (TREE_CODE (t) == UNION_TYPE)
2882 If a union contains a static data member, or a member of
2883 reference type, the program is ill-formed. */
2884 if (TREE_CODE (x) == VAR_DECL)
2886 error ("%q+D may not be static because it is a member of a union", x);
2889 if (TREE_CODE (type) == REFERENCE_TYPE)
2891 error ("%q+D may not have reference type %qT because"
2892 " it is a member of a union",
2898 /* Perform error checking that did not get done in
2900 if (TREE_CODE (type) == FUNCTION_TYPE)
2902 error ("field %q+D invalidly declared function type", x);
2903 type = build_pointer_type (type);
2904 TREE_TYPE (x) = type;
2906 else if (TREE_CODE (type) == METHOD_TYPE)
2908 error ("field %q+D invalidly declared method type", x);
2909 type = build_pointer_type (type);
2910 TREE_TYPE (x) = type;
2913 if (type == error_mark_node)
2916 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
2919 /* Now it can only be a FIELD_DECL. */
2921 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
2922 CLASSTYPE_NON_AGGREGATE (t) = 1;
2924 /* If this is of reference type, check if it needs an init.
2925 Also do a little ANSI jig if necessary. */
2926 if (TREE_CODE (type) == REFERENCE_TYPE)
2928 CLASSTYPE_NON_POD_P (t) = 1;
2929 if (DECL_INITIAL (x) == NULL_TREE)
2930 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2932 /* ARM $12.6.2: [A member initializer list] (or, for an
2933 aggregate, initialization by a brace-enclosed list) is the
2934 only way to initialize nonstatic const and reference
2936 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2938 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
2940 warning (OPT_Wextra, "non-static reference %q+#D in class without a constructor", x);
2943 type = strip_array_types (type);
2945 if (TYPE_PACKED (t))
2947 if (!pod_type_p (type) && !TYPE_PACKED (type))
2951 "ignoring packed attribute because of unpacked non-POD field %q+#D",
2955 else if (TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
2956 DECL_PACKED (x) = 1;
2959 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
2960 /* We don't treat zero-width bitfields as making a class
2965 /* The class is non-empty. */
2966 CLASSTYPE_EMPTY_P (t) = 0;
2967 /* The class is not even nearly empty. */
2968 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
2969 /* If one of the data members contains an empty class,
2971 if (CLASS_TYPE_P (type)
2972 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
2973 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
2976 /* This is used by -Weffc++ (see below). Warn only for pointers
2977 to members which might hold dynamic memory. So do not warn
2978 for pointers to functions or pointers to members. */
2979 if (TYPE_PTR_P (type)
2980 && !TYPE_PTRFN_P (type)
2981 && !TYPE_PTR_TO_MEMBER_P (type))
2982 has_pointers = true;
2984 if (CLASS_TYPE_P (type))
2986 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
2987 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2988 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
2989 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
2992 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
2993 CLASSTYPE_HAS_MUTABLE (t) = 1;
2995 if (! pod_type_p (type))
2996 /* DR 148 now allows pointers to members (which are POD themselves),
2997 to be allowed in POD structs. */
2998 CLASSTYPE_NON_POD_P (t) = 1;
3000 if (! zero_init_p (type))
3001 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3003 /* If any field is const, the structure type is pseudo-const. */
3004 if (CP_TYPE_CONST_P (type))
3006 C_TYPE_FIELDS_READONLY (t) = 1;
3007 if (DECL_INITIAL (x) == NULL_TREE)
3008 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3010 /* ARM $12.6.2: [A member initializer list] (or, for an
3011 aggregate, initialization by a brace-enclosed list) is the
3012 only way to initialize nonstatic const and reference
3014 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3016 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
3018 warning (OPT_Wextra, "non-static const member %q+#D in class without a constructor", x);
3020 /* A field that is pseudo-const makes the structure likewise. */
3021 else if (CLASS_TYPE_P (type))
3023 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3024 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3025 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3026 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3029 /* Core issue 80: A nonstatic data member is required to have a
3030 different name from the class iff the class has a
3031 user-defined constructor. */
3032 if (constructor_name_p (DECL_NAME (x), t) && TYPE_HAS_CONSTRUCTOR (t))
3033 pedwarn ("field %q+#D with same name as class", x);
3035 /* We set DECL_C_BIT_FIELD in grokbitfield.
3036 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3037 if (DECL_C_BIT_FIELD (x))
3038 check_bitfield_decl (x);
3040 check_field_decl (x, t,
3041 cant_have_const_ctor_p,
3043 &any_default_members);
3046 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3047 it should also define a copy constructor and an assignment operator to
3048 implement the correct copy semantic (deep vs shallow, etc.). As it is
3049 not feasible to check whether the constructors do allocate dynamic memory
3050 and store it within members, we approximate the warning like this:
3052 -- Warn only if there are members which are pointers
3053 -- Warn only if there is a non-trivial constructor (otherwise,
3054 there cannot be memory allocated).
3055 -- Warn only if there is a non-trivial destructor. We assume that the
3056 user at least implemented the cleanup correctly, and a destructor
3057 is needed to free dynamic memory.
3059 This seems enough for practical purposes. */
3062 && TYPE_HAS_CONSTRUCTOR (t)
3063 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3064 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3066 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3068 if (! TYPE_HAS_INIT_REF (t))
3070 warning (OPT_Weffc__,
3071 " but does not override %<%T(const %T&)%>", t, t);
3072 if (!TYPE_HAS_ASSIGN_REF (t))
3073 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3075 else if (! TYPE_HAS_ASSIGN_REF (t))
3076 warning (OPT_Weffc__,
3077 " but does not override %<operator=(const %T&)%>", t);
3080 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3082 TYPE_PACKED (t) = 0;
3084 /* Check anonymous struct/anonymous union fields. */
3085 finish_struct_anon (t);
3087 /* We've built up the list of access declarations in reverse order.
3089 *access_decls = nreverse (*access_decls);
3092 /* If TYPE is an empty class type, records its OFFSET in the table of
3096 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3100 if (!is_empty_class (type))
3103 /* Record the location of this empty object in OFFSETS. */
3104 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3106 n = splay_tree_insert (offsets,
3107 (splay_tree_key) offset,
3108 (splay_tree_value) NULL_TREE);
3109 n->value = ((splay_tree_value)
3110 tree_cons (NULL_TREE,
3117 /* Returns nonzero if TYPE is an empty class type and there is
3118 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3121 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3126 if (!is_empty_class (type))
3129 /* Record the location of this empty object in OFFSETS. */
3130 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3134 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3135 if (same_type_p (TREE_VALUE (t), type))
3141 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3142 F for every subobject, passing it the type, offset, and table of
3143 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3146 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3147 than MAX_OFFSET will not be walked.
3149 If F returns a nonzero value, the traversal ceases, and that value
3150 is returned. Otherwise, returns zero. */
3153 walk_subobject_offsets (tree type,
3154 subobject_offset_fn f,
3161 tree type_binfo = NULL_TREE;
3163 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3165 if (max_offset && INT_CST_LT (max_offset, offset))
3168 if (type == error_mark_node)
3173 if (abi_version_at_least (2))
3175 type = BINFO_TYPE (type);
3178 if (CLASS_TYPE_P (type))
3184 /* Avoid recursing into objects that are not interesting. */
3185 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3188 /* Record the location of TYPE. */
3189 r = (*f) (type, offset, offsets);
3193 /* Iterate through the direct base classes of TYPE. */
3195 type_binfo = TYPE_BINFO (type);
3196 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3200 if (abi_version_at_least (2)
3201 && BINFO_VIRTUAL_P (binfo))
3205 && BINFO_VIRTUAL_P (binfo)
3206 && !BINFO_PRIMARY_P (binfo))
3209 if (!abi_version_at_least (2))
3210 binfo_offset = size_binop (PLUS_EXPR,
3212 BINFO_OFFSET (binfo));
3216 /* We cannot rely on BINFO_OFFSET being set for the base
3217 class yet, but the offsets for direct non-virtual
3218 bases can be calculated by going back to the TYPE. */
3219 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3220 binfo_offset = size_binop (PLUS_EXPR,
3222 BINFO_OFFSET (orig_binfo));
3225 r = walk_subobject_offsets (binfo,
3230 (abi_version_at_least (2)
3231 ? /*vbases_p=*/0 : vbases_p));
3236 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3239 VEC(tree,gc) *vbases;
3241 /* Iterate through the virtual base classes of TYPE. In G++
3242 3.2, we included virtual bases in the direct base class
3243 loop above, which results in incorrect results; the
3244 correct offsets for virtual bases are only known when
3245 working with the most derived type. */
3247 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3248 VEC_iterate (tree, vbases, ix, binfo); ix++)
3250 r = walk_subobject_offsets (binfo,
3252 size_binop (PLUS_EXPR,
3254 BINFO_OFFSET (binfo)),
3263 /* We still have to walk the primary base, if it is
3264 virtual. (If it is non-virtual, then it was walked
3266 tree vbase = get_primary_binfo (type_binfo);
3268 if (vbase && BINFO_VIRTUAL_P (vbase)
3269 && BINFO_PRIMARY_P (vbase)
3270 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3272 r = (walk_subobject_offsets
3274 offsets, max_offset, /*vbases_p=*/0));
3281 /* Iterate through the fields of TYPE. */
3282 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3283 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3287 if (abi_version_at_least (2))
3288 field_offset = byte_position (field);
3290 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3291 field_offset = DECL_FIELD_OFFSET (field);
3293 r = walk_subobject_offsets (TREE_TYPE (field),
3295 size_binop (PLUS_EXPR,
3305 else if (TREE_CODE (type) == ARRAY_TYPE)
3307 tree element_type = strip_array_types (type);
3308 tree domain = TYPE_DOMAIN (type);
3311 /* Avoid recursing into objects that are not interesting. */
3312 if (!CLASS_TYPE_P (element_type)
3313 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3316 /* Step through each of the elements in the array. */
3317 for (index = size_zero_node;
3318 /* G++ 3.2 had an off-by-one error here. */
3319 (abi_version_at_least (2)
3320 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3321 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3322 index = size_binop (PLUS_EXPR, index, size_one_node))
3324 r = walk_subobject_offsets (TREE_TYPE (type),
3332 offset = size_binop (PLUS_EXPR, offset,
3333 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3334 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3335 there's no point in iterating through the remaining
3336 elements of the array. */
3337 if (max_offset && INT_CST_LT (max_offset, offset))
3345 /* Record all of the empty subobjects of TYPE (either a type or a
3346 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3347 is being placed at OFFSET; otherwise, it is a base class that is
3348 being placed at OFFSET. */
3351 record_subobject_offsets (tree type,
3354 bool is_data_member)
3357 /* If recording subobjects for a non-static data member or a
3358 non-empty base class , we do not need to record offsets beyond
3359 the size of the biggest empty class. Additional data members
3360 will go at the end of the class. Additional base classes will go
3361 either at offset zero (if empty, in which case they cannot
3362 overlap with offsets past the size of the biggest empty class) or
3363 at the end of the class.
3365 However, if we are placing an empty base class, then we must record
3366 all offsets, as either the empty class is at offset zero (where
3367 other empty classes might later be placed) or at the end of the
3368 class (where other objects might then be placed, so other empty
3369 subobjects might later overlap). */
3371 || !is_empty_class (BINFO_TYPE (type)))
3372 max_offset = sizeof_biggest_empty_class;
3374 max_offset = NULL_TREE;
3375 walk_subobject_offsets (type, record_subobject_offset, offset,
3376 offsets, max_offset, is_data_member);
3379 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3380 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3381 virtual bases of TYPE are examined. */
3384 layout_conflict_p (tree type,
3389 splay_tree_node max_node;
3391 /* Get the node in OFFSETS that indicates the maximum offset where
3392 an empty subobject is located. */
3393 max_node = splay_tree_max (offsets);
3394 /* If there aren't any empty subobjects, then there's no point in
3395 performing this check. */
3399 return walk_subobject_offsets (type, check_subobject_offset, offset,
3400 offsets, (tree) (max_node->key),
3404 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3405 non-static data member of the type indicated by RLI. BINFO is the
3406 binfo corresponding to the base subobject, OFFSETS maps offsets to
3407 types already located at those offsets. This function determines
3408 the position of the DECL. */
3411 layout_nonempty_base_or_field (record_layout_info rli,
3416 tree offset = NULL_TREE;
3422 /* For the purposes of determining layout conflicts, we want to
3423 use the class type of BINFO; TREE_TYPE (DECL) will be the
3424 CLASSTYPE_AS_BASE version, which does not contain entries for
3425 zero-sized bases. */
3426 type = TREE_TYPE (binfo);
3431 type = TREE_TYPE (decl);
3435 /* Try to place the field. It may take more than one try if we have
3436 a hard time placing the field without putting two objects of the
3437 same type at the same address. */
3440 struct record_layout_info_s old_rli = *rli;
3442 /* Place this field. */
3443 place_field (rli, decl);
3444 offset = byte_position (decl);
3446 /* We have to check to see whether or not there is already
3447 something of the same type at the offset we're about to use.
3448 For example, consider:
3451 struct T : public S { int i; };
3452 struct U : public S, public T {};
3454 Here, we put S at offset zero in U. Then, we can't put T at
3455 offset zero -- its S component would be at the same address
3456 as the S we already allocated. So, we have to skip ahead.
3457 Since all data members, including those whose type is an
3458 empty class, have nonzero size, any overlap can happen only
3459 with a direct or indirect base-class -- it can't happen with
3461 /* In a union, overlap is permitted; all members are placed at
3463 if (TREE_CODE (rli->t) == UNION_TYPE)
3465 /* G++ 3.2 did not check for overlaps when placing a non-empty
3467 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3469 if (layout_conflict_p (field_p ? type : binfo, offset,
3472 /* Strip off the size allocated to this field. That puts us
3473 at the first place we could have put the field with
3474 proper alignment. */
3477 /* Bump up by the alignment required for the type. */
3479 = size_binop (PLUS_EXPR, rli->bitpos,
3481 ? CLASSTYPE_ALIGN (type)
3482 : TYPE_ALIGN (type)));
3483 normalize_rli (rli);
3486 /* There was no conflict. We're done laying out this field. */
3490 /* Now that we know where it will be placed, update its
3492 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3493 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3494 this point because their BINFO_OFFSET is copied from another
3495 hierarchy. Therefore, we may not need to add the entire
3497 propagate_binfo_offsets (binfo,
3498 size_diffop (convert (ssizetype, offset),
3500 BINFO_OFFSET (binfo))));
3503 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3506 empty_base_at_nonzero_offset_p (tree type,
3508 splay_tree offsets ATTRIBUTE_UNUSED)
3510 return is_empty_class (type) && !integer_zerop (offset);
3513 /* Layout the empty base BINFO. EOC indicates the byte currently just
3514 past the end of the class, and should be correctly aligned for a
3515 class of the type indicated by BINFO; OFFSETS gives the offsets of
3516 the empty bases allocated so far. T is the most derived
3517 type. Return nonzero iff we added it at the end. */
3520 layout_empty_base (tree binfo, tree eoc, splay_tree offsets)
3523 tree basetype = BINFO_TYPE (binfo);
3526 /* This routine should only be used for empty classes. */
3527 gcc_assert (is_empty_class (basetype));
3528 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3530 if (!integer_zerop (BINFO_OFFSET (binfo)))
3532 if (abi_version_at_least (2))
3533 propagate_binfo_offsets
3534 (binfo, size_diffop (size_zero_node, BINFO_OFFSET (binfo)));
3537 "offset of empty base %qT may not be ABI-compliant and may"
3538 "change in a future version of GCC",
3539 BINFO_TYPE (binfo));
3542 /* This is an empty base class. We first try to put it at offset
3544 if (layout_conflict_p (binfo,
3545 BINFO_OFFSET (binfo),
3549 /* That didn't work. Now, we move forward from the next
3550 available spot in the class. */
3552 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3555 if (!layout_conflict_p (binfo,
3556 BINFO_OFFSET (binfo),
3559 /* We finally found a spot where there's no overlap. */
3562 /* There's overlap here, too. Bump along to the next spot. */
3563 propagate_binfo_offsets (binfo, alignment);
3569 /* Layout the base given by BINFO in the class indicated by RLI.
3570 *BASE_ALIGN is a running maximum of the alignments of
3571 any base class. OFFSETS gives the location of empty base
3572 subobjects. T is the most derived type. Return nonzero if the new
3573 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3574 *NEXT_FIELD, unless BINFO is for an empty base class.
3576 Returns the location at which the next field should be inserted. */
3579 build_base_field (record_layout_info rli, tree binfo,
3580 splay_tree offsets, tree *next_field)
3583 tree basetype = BINFO_TYPE (binfo);
3585 if (!COMPLETE_TYPE_P (basetype))
3586 /* This error is now reported in xref_tag, thus giving better
3587 location information. */
3590 /* Place the base class. */
3591 if (!is_empty_class (basetype))
3595 /* The containing class is non-empty because it has a non-empty
3597 CLASSTYPE_EMPTY_P (t) = 0;
3599 /* Create the FIELD_DECL. */
3600 decl = build_decl (FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3601 DECL_ARTIFICIAL (decl) = 1;
3602 DECL_IGNORED_P (decl) = 1;
3603 DECL_FIELD_CONTEXT (decl) = t;
3604 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3605 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3606 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3607 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3608 DECL_MODE (decl) = TYPE_MODE (basetype);
3609 DECL_FIELD_IS_BASE (decl) = 1;
3611 /* Try to place the field. It may take more than one try if we
3612 have a hard time placing the field without putting two
3613 objects of the same type at the same address. */
3614 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3615 /* Add the new FIELD_DECL to the list of fields for T. */
3616 TREE_CHAIN (decl) = *next_field;
3618 next_field = &TREE_CHAIN (decl);
3625 /* On some platforms (ARM), even empty classes will not be
3627 eoc = round_up (rli_size_unit_so_far (rli),
3628 CLASSTYPE_ALIGN_UNIT (basetype));
3629 atend = layout_empty_base (binfo, eoc, offsets);
3630 /* A nearly-empty class "has no proper base class that is empty,
3631 not morally virtual, and at an offset other than zero." */
3632 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3635 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3636 /* The check above (used in G++ 3.2) is insufficient because
3637 an empty class placed at offset zero might itself have an
3638 empty base at a nonzero offset. */
3639 else if (walk_subobject_offsets (basetype,
3640 empty_base_at_nonzero_offset_p,
3643 /*max_offset=*/NULL_TREE,
3646 if (abi_version_at_least (2))
3647 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3650 "class %qT will be considered nearly empty in a "
3651 "future version of GCC", t);
3655 /* We do not create a FIELD_DECL for empty base classes because
3656 it might overlap some other field. We want to be able to
3657 create CONSTRUCTORs for the class by iterating over the
3658 FIELD_DECLs, and the back end does not handle overlapping
3661 /* An empty virtual base causes a class to be non-empty
3662 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3663 here because that was already done when the virtual table
3664 pointer was created. */
3667 /* Record the offsets of BINFO and its base subobjects. */
3668 record_subobject_offsets (binfo,
3669 BINFO_OFFSET (binfo),
3671 /*is_data_member=*/false);
3676 /* Layout all of the non-virtual base classes. Record empty
3677 subobjects in OFFSETS. T is the most derived type. Return nonzero
3678 if the type cannot be nearly empty. The fields created
3679 corresponding to the base classes will be inserted at
3683 build_base_fields (record_layout_info rli,
3684 splay_tree offsets, tree *next_field)
3686 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3689 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3692 /* The primary base class is always allocated first. */
3693 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3694 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3695 offsets, next_field);
3697 /* Now allocate the rest of the bases. */
3698 for (i = 0; i < n_baseclasses; ++i)
3702 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3704 /* The primary base was already allocated above, so we don't
3705 need to allocate it again here. */
3706 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3709 /* Virtual bases are added at the end (a primary virtual base
3710 will have already been added). */
3711 if (BINFO_VIRTUAL_P (base_binfo))
3714 next_field = build_base_field (rli, base_binfo,
3715 offsets, next_field);
3719 /* Go through the TYPE_METHODS of T issuing any appropriate
3720 diagnostics, figuring out which methods override which other
3721 methods, and so forth. */
3724 check_methods (tree t)
3728 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3730 check_for_override (x, t);
3731 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3732 error ("initializer specified for non-virtual method %q+D", x);
3733 /* The name of the field is the original field name
3734 Save this in auxiliary field for later overloading. */
3735 if (DECL_VINDEX (x))
3737 TYPE_POLYMORPHIC_P (t) = 1;
3738 if (DECL_PURE_VIRTUAL_P (x))
3739 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3741 /* All user-declared destructors are non-trivial. */
3742 if (DECL_DESTRUCTOR_P (x))
3743 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3747 /* FN is a constructor or destructor. Clone the declaration to create
3748 a specialized in-charge or not-in-charge version, as indicated by
3752 build_clone (tree fn, tree name)
3757 /* Copy the function. */
3758 clone = copy_decl (fn);
3759 /* Remember where this function came from. */
3760 DECL_CLONED_FUNCTION (clone) = fn;
3761 DECL_ABSTRACT_ORIGIN (clone) = fn;
3762 /* Reset the function name. */
3763 DECL_NAME (clone) = name;
3764 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3765 /* There's no pending inline data for this function. */
3766 DECL_PENDING_INLINE_INFO (clone) = NULL;
3767 DECL_PENDING_INLINE_P (clone) = 0;
3768 /* And it hasn't yet been deferred. */
3769 DECL_DEFERRED_FN (clone) = 0;
3771 /* The base-class destructor is not virtual. */
3772 if (name == base_dtor_identifier)
3774 DECL_VIRTUAL_P (clone) = 0;
3775 if (TREE_CODE (clone) != TEMPLATE_DECL)
3776 DECL_VINDEX (clone) = NULL_TREE;
3779 /* If there was an in-charge parameter, drop it from the function
3781 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3787 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3788 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3789 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3790 /* Skip the `this' parameter. */
3791 parmtypes = TREE_CHAIN (parmtypes);
3792 /* Skip the in-charge parameter. */
3793 parmtypes = TREE_CHAIN (parmtypes);
3794 /* And the VTT parm, in a complete [cd]tor. */
3795 if (DECL_HAS_VTT_PARM_P (fn)
3796 && ! DECL_NEEDS_VTT_PARM_P (clone))
3797 parmtypes = TREE_CHAIN (parmtypes);
3798 /* If this is subobject constructor or destructor, add the vtt
3801 = build_method_type_directly (basetype,
3802 TREE_TYPE (TREE_TYPE (clone)),
3805 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3808 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3809 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3812 /* Copy the function parameters. But, DECL_ARGUMENTS on a TEMPLATE_DECL
3813 aren't function parameters; those are the template parameters. */
3814 if (TREE_CODE (clone) != TEMPLATE_DECL)
3816 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3817 /* Remove the in-charge parameter. */
3818 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3820 TREE_CHAIN (DECL_ARGUMENTS (clone))
3821 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3822 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3824 /* And the VTT parm, in a complete [cd]tor. */
3825 if (DECL_HAS_VTT_PARM_P (fn))
3827 if (DECL_NEEDS_VTT_PARM_P (clone))
3828 DECL_HAS_VTT_PARM_P (clone) = 1;
3831 TREE_CHAIN (DECL_ARGUMENTS (clone))
3832 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3833 DECL_HAS_VTT_PARM_P (clone) = 0;
3837 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3839 DECL_CONTEXT (parms) = clone;
3840 cxx_dup_lang_specific_decl (parms);
3844 /* Create the RTL for this function. */
3845 SET_DECL_RTL (clone, NULL_RTX);
3846 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3848 /* Make it easy to find the CLONE given the FN. */
3849 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3850 TREE_CHAIN (fn) = clone;
3852 /* If this is a template, handle the DECL_TEMPLATE_RESULT as well. */
3853 if (TREE_CODE (clone) == TEMPLATE_DECL)
3857 DECL_TEMPLATE_RESULT (clone)
3858 = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3859 result = DECL_TEMPLATE_RESULT (clone);
3860 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3861 DECL_TI_TEMPLATE (result) = clone;
3864 note_decl_for_pch (clone);
3869 /* Produce declarations for all appropriate clones of FN. If
3870 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
3871 CLASTYPE_METHOD_VEC as well. */
3874 clone_function_decl (tree fn, int update_method_vec_p)
3878 /* Avoid inappropriate cloning. */
3880 && DECL_CLONED_FUNCTION (TREE_CHAIN (fn)))
3883 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
3885 /* For each constructor, we need two variants: an in-charge version
3886 and a not-in-charge version. */
3887 clone = build_clone (fn, complete_ctor_identifier);
3888 if (update_method_vec_p)
3889 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3890 clone = build_clone (fn, base_ctor_identifier);
3891 if (update_method_vec_p)
3892 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3896 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
3898 /* For each destructor, we need three variants: an in-charge
3899 version, a not-in-charge version, and an in-charge deleting
3900 version. We clone the deleting version first because that
3901 means it will go second on the TYPE_METHODS list -- and that
3902 corresponds to the correct layout order in the virtual
3905 For a non-virtual destructor, we do not build a deleting
3907 if (DECL_VIRTUAL_P (fn))
3909 clone = build_clone (fn, deleting_dtor_identifier);
3910 if (update_method_vec_p)
3911 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3913 clone = build_clone (fn, complete_dtor_identifier);
3914 if (update_method_vec_p)
3915 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3916 clone = build_clone (fn, base_dtor_identifier);
3917 if (update_method_vec_p)
3918 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3921 /* Note that this is an abstract function that is never emitted. */
3922 DECL_ABSTRACT (fn) = 1;
3925 /* DECL is an in charge constructor, which is being defined. This will
3926 have had an in class declaration, from whence clones were
3927 declared. An out-of-class definition can specify additional default
3928 arguments. As it is the clones that are involved in overload
3929 resolution, we must propagate the information from the DECL to its
3933 adjust_clone_args (tree decl)
3937 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION (clone);
3938 clone = TREE_CHAIN (clone))
3940 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
3941 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
3942 tree decl_parms, clone_parms;
3944 clone_parms = orig_clone_parms;
3946 /* Skip the 'this' parameter. */
3947 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
3948 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3950 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
3951 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3952 if (DECL_HAS_VTT_PARM_P (decl))
3953 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3955 clone_parms = orig_clone_parms;
3956 if (DECL_HAS_VTT_PARM_P (clone))
3957 clone_parms = TREE_CHAIN (clone_parms);
3959 for (decl_parms = orig_decl_parms; decl_parms;
3960 decl_parms = TREE_CHAIN (decl_parms),
3961 clone_parms = TREE_CHAIN (clone_parms))
3963 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
3964 TREE_TYPE (clone_parms)));
3966 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
3968 /* A default parameter has been added. Adjust the
3969 clone's parameters. */
3970 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3971 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3974 clone_parms = orig_decl_parms;
3976 if (DECL_HAS_VTT_PARM_P (clone))
3978 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
3979 TREE_VALUE (orig_clone_parms),
3981 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
3983 type = build_method_type_directly (basetype,
3984 TREE_TYPE (TREE_TYPE (clone)),
3987 type = build_exception_variant (type, exceptions);
3988 TREE_TYPE (clone) = type;
3990 clone_parms = NULL_TREE;
3994 gcc_assert (!clone_parms);
3998 /* For each of the constructors and destructors in T, create an
3999 in-charge and not-in-charge variant. */
4002 clone_constructors_and_destructors (tree t)
4006 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4008 if (!CLASSTYPE_METHOD_VEC (t))
4011 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4012 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4013 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4014 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4017 /* Remove all zero-width bit-fields from T. */
4020 remove_zero_width_bit_fields (tree t)
4024 fieldsp = &TYPE_FIELDS (t);
4027 if (TREE_CODE (*fieldsp) == FIELD_DECL
4028 && DECL_C_BIT_FIELD (*fieldsp)
4029 && DECL_INITIAL (*fieldsp))
4030 *fieldsp = TREE_CHAIN (*fieldsp);
4032 fieldsp = &TREE_CHAIN (*fieldsp);
4036 /* Returns TRUE iff we need a cookie when dynamically allocating an
4037 array whose elements have the indicated class TYPE. */
4040 type_requires_array_cookie (tree type)
4043 bool has_two_argument_delete_p = false;
4045 gcc_assert (CLASS_TYPE_P (type));
4047 /* If there's a non-trivial destructor, we need a cookie. In order
4048 to iterate through the array calling the destructor for each
4049 element, we'll have to know how many elements there are. */
4050 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4053 /* If the usual deallocation function is a two-argument whose second
4054 argument is of type `size_t', then we have to pass the size of
4055 the array to the deallocation function, so we will need to store
4057 fns = lookup_fnfields (TYPE_BINFO (type),
4058 ansi_opname (VEC_DELETE_EXPR),
4060 /* If there are no `operator []' members, or the lookup is
4061 ambiguous, then we don't need a cookie. */
4062 if (!fns || fns == error_mark_node)
4064 /* Loop through all of the functions. */
4065 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4070 /* Select the current function. */
4071 fn = OVL_CURRENT (fns);
4072 /* See if this function is a one-argument delete function. If
4073 it is, then it will be the usual deallocation function. */
4074 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4075 if (second_parm == void_list_node)
4077 /* Otherwise, if we have a two-argument function and the second
4078 argument is `size_t', it will be the usual deallocation
4079 function -- unless there is one-argument function, too. */
4080 if (TREE_CHAIN (second_parm) == void_list_node
4081 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4082 has_two_argument_delete_p = true;
4085 return has_two_argument_delete_p;
4088 /* Check the validity of the bases and members declared in T. Add any
4089 implicitly-generated functions (like copy-constructors and
4090 assignment operators). Compute various flag bits (like
4091 CLASSTYPE_NON_POD_T) for T. This routine works purely at the C++
4092 level: i.e., independently of the ABI in use. */
4095 check_bases_and_members (tree t)
4097 /* Nonzero if the implicitly generated copy constructor should take
4098 a non-const reference argument. */
4099 int cant_have_const_ctor;
4100 /* Nonzero if the implicitly generated assignment operator
4101 should take a non-const reference argument. */
4102 int no_const_asn_ref;
4105 /* By default, we use const reference arguments and generate default
4107 cant_have_const_ctor = 0;
4108 no_const_asn_ref = 0;
4110 /* Check all the base-classes. */
4111 check_bases (t, &cant_have_const_ctor,
4114 /* Check all the method declarations. */
4117 /* Check all the data member declarations. We cannot call
4118 check_field_decls until we have called check_bases check_methods,
4119 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4120 being set appropriately. */
4121 check_field_decls (t, &access_decls,
4122 &cant_have_const_ctor,
4125 /* A nearly-empty class has to be vptr-containing; a nearly empty
4126 class contains just a vptr. */
4127 if (!TYPE_CONTAINS_VPTR_P (t))
4128 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4130 /* Do some bookkeeping that will guide the generation of implicitly
4131 declared member functions. */
4132 TYPE_HAS_COMPLEX_INIT_REF (t)
4133 |= (TYPE_HAS_INIT_REF (t) || TYPE_CONTAINS_VPTR_P (t));
4134 TYPE_NEEDS_CONSTRUCTING (t)
4135 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_CONTAINS_VPTR_P (t));
4136 CLASSTYPE_NON_AGGREGATE (t)
4137 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_POLYMORPHIC_P (t));
4138 CLASSTYPE_NON_POD_P (t)
4139 |= (CLASSTYPE_NON_AGGREGATE (t)
4140 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
4141 || TYPE_HAS_ASSIGN_REF (t));
4142 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
4143 |= TYPE_HAS_ASSIGN_REF (t) || TYPE_CONTAINS_VPTR_P (t);
4144 TYPE_HAS_COMPLEX_DFLT (t)
4145 |= (TYPE_HAS_DEFAULT_CONSTRUCTOR (t) || TYPE_CONTAINS_VPTR_P (t));
4147 /* Synthesize any needed methods. */
4148 add_implicitly_declared_members (t,
4149 cant_have_const_ctor,
4152 /* Create the in-charge and not-in-charge variants of constructors
4154 clone_constructors_and_destructors (t);
4156 /* Process the using-declarations. */
4157 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4158 handle_using_decl (TREE_VALUE (access_decls), t);
4160 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4161 finish_struct_methods (t);
4163 /* Figure out whether or not we will need a cookie when dynamically
4164 allocating an array of this type. */
4165 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4166 = type_requires_array_cookie (t);
4169 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4170 accordingly. If a new vfield was created (because T doesn't have a
4171 primary base class), then the newly created field is returned. It
4172 is not added to the TYPE_FIELDS list; it is the caller's
4173 responsibility to do that. Accumulate declared virtual functions
4177 create_vtable_ptr (tree t, tree* virtuals_p)
4181 /* Collect the virtual functions declared in T. */
4182 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4183 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4184 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4186 tree new_virtual = make_node (TREE_LIST);
4188 BV_FN (new_virtual) = fn;
4189 BV_DELTA (new_virtual) = integer_zero_node;
4190 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4192 TREE_CHAIN (new_virtual) = *virtuals_p;
4193 *virtuals_p = new_virtual;
4196 /* If we couldn't find an appropriate base class, create a new field
4197 here. Even if there weren't any new virtual functions, we might need a
4198 new virtual function table if we're supposed to include vptrs in
4199 all classes that need them. */
4200 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4202 /* We build this decl with vtbl_ptr_type_node, which is a
4203 `vtable_entry_type*'. It might seem more precise to use
4204 `vtable_entry_type (*)[N]' where N is the number of virtual
4205 functions. However, that would require the vtable pointer in
4206 base classes to have a different type than the vtable pointer
4207 in derived classes. We could make that happen, but that
4208 still wouldn't solve all the problems. In particular, the
4209 type-based alias analysis code would decide that assignments
4210 to the base class vtable pointer can't alias assignments to
4211 the derived class vtable pointer, since they have different
4212 types. Thus, in a derived class destructor, where the base
4213 class constructor was inlined, we could generate bad code for
4214 setting up the vtable pointer.
4216 Therefore, we use one type for all vtable pointers. We still
4217 use a type-correct type; it's just doesn't indicate the array
4218 bounds. That's better than using `void*' or some such; it's
4219 cleaner, and it let's the alias analysis code know that these
4220 stores cannot alias stores to void*! */
4223 field = build_decl (FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4224 DECL_VIRTUAL_P (field) = 1;
4225 DECL_ARTIFICIAL (field) = 1;
4226 DECL_FIELD_CONTEXT (field) = t;
4227 DECL_FCONTEXT (field) = t;
4229 TYPE_VFIELD (t) = field;
4231 /* This class is non-empty. */
4232 CLASSTYPE_EMPTY_P (t) = 0;
4240 /* Fixup the inline function given by INFO now that the class is
4244 fixup_pending_inline (tree fn)
4246 if (DECL_PENDING_INLINE_INFO (fn))
4248 tree args = DECL_ARGUMENTS (fn);
4251 DECL_CONTEXT (args) = fn;
4252 args = TREE_CHAIN (args);
4257 /* Fixup the inline methods and friends in TYPE now that TYPE is
4261 fixup_inline_methods (tree type)
4263 tree method = TYPE_METHODS (type);
4264 VEC(tree,gc) *friends;
4267 if (method && TREE_CODE (method) == TREE_VEC)
4269 if (TREE_VEC_ELT (method, 1))
4270 method = TREE_VEC_ELT (method, 1);
4271 else if (TREE_VEC_ELT (method, 0))
4272 method = TREE_VEC_ELT (method, 0);
4274 method = TREE_VEC_ELT (method, 2);
4277 /* Do inline member functions. */
4278 for (; method; method = TREE_CHAIN (method))
4279 fixup_pending_inline (method);
4282 for (friends = CLASSTYPE_INLINE_FRIENDS (type), ix = 0;
4283 VEC_iterate (tree, friends, ix, method); ix++)
4284 fixup_pending_inline (method);
4285 CLASSTYPE_INLINE_FRIENDS (type) = NULL;
4288 /* Add OFFSET to all base types of BINFO which is a base in the
4289 hierarchy dominated by T.
4291 OFFSET, which is a type offset, is number of bytes. */
4294 propagate_binfo_offsets (tree binfo, tree offset)
4300 /* Update BINFO's offset. */
4301 BINFO_OFFSET (binfo)
4302 = convert (sizetype,
4303 size_binop (PLUS_EXPR,
4304 convert (ssizetype, BINFO_OFFSET (binfo)),
4307 /* Find the primary base class. */
4308 primary_binfo = get_primary_binfo (binfo);
4310 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4311 propagate_binfo_offsets (primary_binfo, offset);
4313 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4315 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4317 /* Don't do the primary base twice. */
4318 if (base_binfo == primary_binfo)
4321 if (BINFO_VIRTUAL_P (base_binfo))
4324 propagate_binfo_offsets (base_binfo, offset);
4328 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4329 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4330 empty subobjects of T. */
4333 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4337 bool first_vbase = true;
4340 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4343 if (!abi_version_at_least(2))
4345 /* In G++ 3.2, we incorrectly rounded the size before laying out
4346 the virtual bases. */
4347 finish_record_layout (rli, /*free_p=*/false);
4348 #ifdef STRUCTURE_SIZE_BOUNDARY
4349 /* Packed structures don't need to have minimum size. */
4350 if (! TYPE_PACKED (t))
4351 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4353 rli->offset = TYPE_SIZE_UNIT (t);
4354 rli->bitpos = bitsize_zero_node;
4355 rli->record_align = TYPE_ALIGN (t);
4358 /* Find the last field. The artificial fields created for virtual
4359 bases will go after the last extant field to date. */
4360 next_field = &TYPE_FIELDS (t);
4362 next_field = &TREE_CHAIN (*next_field);
4364 /* Go through the virtual bases, allocating space for each virtual
4365 base that is not already a primary base class. These are
4366 allocated in inheritance graph order. */
4367 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4369 if (!BINFO_VIRTUAL_P (vbase))
4372 if (!BINFO_PRIMARY_P (vbase))
4374 tree basetype = TREE_TYPE (vbase);
4376 /* This virtual base is not a primary base of any class in the
4377 hierarchy, so we have to add space for it. */
4378 next_field = build_base_field (rli, vbase,
4379 offsets, next_field);
4381 /* If the first virtual base might have been placed at a
4382 lower address, had we started from CLASSTYPE_SIZE, rather
4383 than TYPE_SIZE, issue a warning. There can be both false
4384 positives and false negatives from this warning in rare
4385 cases; to deal with all the possibilities would probably
4386 require performing both layout algorithms and comparing
4387 the results which is not particularly tractable. */
4391 (size_binop (CEIL_DIV_EXPR,
4392 round_up (CLASSTYPE_SIZE (t),
4393 CLASSTYPE_ALIGN (basetype)),
4395 BINFO_OFFSET (vbase))))
4397 "offset of virtual base %qT is not ABI-compliant and "
4398 "may change in a future version of GCC",
4401 first_vbase = false;
4406 /* Returns the offset of the byte just past the end of the base class
4410 end_of_base (tree binfo)
4414 if (is_empty_class (BINFO_TYPE (binfo)))
4415 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4416 allocate some space for it. It cannot have virtual bases, so
4417 TYPE_SIZE_UNIT is fine. */
4418 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4420 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4422 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4425 /* Returns the offset of the byte just past the end of the base class
4426 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4427 only non-virtual bases are included. */
4430 end_of_class (tree t, int include_virtuals_p)
4432 tree result = size_zero_node;
4433 VEC(tree,gc) *vbases;
4439 for (binfo = TYPE_BINFO (t), i = 0;
4440 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4442 if (!include_virtuals_p
4443 && BINFO_VIRTUAL_P (base_binfo)
4444 && (!BINFO_PRIMARY_P (base_binfo)
4445 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4448 offset = end_of_base (base_binfo);
4449 if (INT_CST_LT_UNSIGNED (result, offset))
4453 /* G++ 3.2 did not check indirect virtual bases. */
4454 if (abi_version_at_least (2) && include_virtuals_p)
4455 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4456 VEC_iterate (tree, vbases, i, base_binfo); i++)
4458 offset = end_of_base (base_binfo);
4459 if (INT_CST_LT_UNSIGNED (result, offset))
4466 /* Warn about bases of T that are inaccessible because they are
4467 ambiguous. For example:
4470 struct T : public S {};
4471 struct U : public S, public T {};
4473 Here, `(S*) new U' is not allowed because there are two `S'
4477 warn_about_ambiguous_bases (tree t)
4480 VEC(tree,gc) *vbases;
4485 /* If there are no repeated bases, nothing can be ambiguous. */
4486 if (!CLASSTYPE_REPEATED_BASE_P (t))
4489 /* Check direct bases. */
4490 for (binfo = TYPE_BINFO (t), i = 0;
4491 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4493 basetype = BINFO_TYPE (base_binfo);
4495 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4496 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4500 /* Check for ambiguous virtual bases. */
4502 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4503 VEC_iterate (tree, vbases, i, binfo); i++)
4505 basetype = BINFO_TYPE (binfo);
4507 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4508 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4513 /* Compare two INTEGER_CSTs K1 and K2. */
4516 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4518 return tree_int_cst_compare ((tree) k1, (tree) k2);
4521 /* Increase the size indicated in RLI to account for empty classes
4522 that are "off the end" of the class. */
4525 include_empty_classes (record_layout_info rli)
4530 /* It might be the case that we grew the class to allocate a
4531 zero-sized base class. That won't be reflected in RLI, yet,
4532 because we are willing to overlay multiple bases at the same
4533 offset. However, now we need to make sure that RLI is big enough
4534 to reflect the entire class. */
4535 eoc = end_of_class (rli->t,
4536 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4537 rli_size = rli_size_unit_so_far (rli);
4538 if (TREE_CODE (rli_size) == INTEGER_CST
4539 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4541 if (!abi_version_at_least (2))
4542 /* In version 1 of the ABI, the size of a class that ends with
4543 a bitfield was not rounded up to a whole multiple of a
4544 byte. Because rli_size_unit_so_far returns only the number
4545 of fully allocated bytes, any extra bits were not included
4547 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4549 /* The size should have been rounded to a whole byte. */
4550 gcc_assert (tree_int_cst_equal
4551 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4553 = size_binop (PLUS_EXPR,
4555 size_binop (MULT_EXPR,
4556 convert (bitsizetype,
4557 size_binop (MINUS_EXPR,
4559 bitsize_int (BITS_PER_UNIT)));
4560 normalize_rli (rli);
4564 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4565 BINFO_OFFSETs for all of the base-classes. Position the vtable
4566 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4569 layout_class_type (tree t, tree *virtuals_p)
4571 tree non_static_data_members;
4574 record_layout_info rli;
4575 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4576 types that appear at that offset. */
4577 splay_tree empty_base_offsets;
4578 /* True if the last field layed out was a bit-field. */
4579 bool last_field_was_bitfield = false;
4580 /* The location at which the next field should be inserted. */
4582 /* T, as a base class. */
4585 /* Keep track of the first non-static data member. */
4586 non_static_data_members = TYPE_FIELDS (t);
4588 /* Start laying out the record. */
4589 rli = start_record_layout (t);
4591 /* Mark all the primary bases in the hierarchy. */
4592 determine_primary_bases (t);
4594 /* Create a pointer to our virtual function table. */
4595 vptr = create_vtable_ptr (t, virtuals_p);
4597 /* The vptr is always the first thing in the class. */
4600 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4601 TYPE_FIELDS (t) = vptr;
4602 next_field = &TREE_CHAIN (vptr);
4603 place_field (rli, vptr);
4606 next_field = &TYPE_FIELDS (t);
4608 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4609 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4611 build_base_fields (rli, empty_base_offsets, next_field);
4613 /* Layout the non-static data members. */
4614 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4619 /* We still pass things that aren't non-static data members to
4620 the back end, in case it wants to do something with them. */
4621 if (TREE_CODE (field) != FIELD_DECL)
4623 place_field (rli, field);
4624 /* If the static data member has incomplete type, keep track
4625 of it so that it can be completed later. (The handling
4626 of pending statics in finish_record_layout is
4627 insufficient; consider:
4630 struct S2 { static S1 s1; };
4632 At this point, finish_record_layout will be called, but
4633 S1 is still incomplete.) */
4634 if (TREE_CODE (field) == VAR_DECL)
4636 maybe_register_incomplete_var (field);
4637 /* The visibility of static data members is determined
4638 at their point of declaration, not their point of
4640 determine_visibility (field);
4645 type = TREE_TYPE (field);
4646 if (type == error_mark_node)
4649 padding = NULL_TREE;
4651 /* If this field is a bit-field whose width is greater than its
4652 type, then there are some special rules for allocating
4654 if (DECL_C_BIT_FIELD (field)
4655 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4657 integer_type_kind itk;
4659 bool was_unnamed_p = false;
4660 /* We must allocate the bits as if suitably aligned for the
4661 longest integer type that fits in this many bits. type
4662 of the field. Then, we are supposed to use the left over
4663 bits as additional padding. */
4664 for (itk = itk_char; itk != itk_none; ++itk)
4665 if (INT_CST_LT (DECL_SIZE (field),
4666 TYPE_SIZE (integer_types[itk])))
4669 /* ITK now indicates a type that is too large for the
4670 field. We have to back up by one to find the largest
4672 integer_type = integer_types[itk - 1];
4674 /* Figure out how much additional padding is required. GCC
4675 3.2 always created a padding field, even if it had zero
4677 if (!abi_version_at_least (2)
4678 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4680 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4681 /* In a union, the padding field must have the full width
4682 of the bit-field; all fields start at offset zero. */
4683 padding = DECL_SIZE (field);
4686 if (TREE_CODE (t) == UNION_TYPE)
4687 warning (OPT_Wabi, "size assigned to %qT may not be "
4688 "ABI-compliant and may change in a future "
4691 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4692 TYPE_SIZE (integer_type));
4695 #ifdef PCC_BITFIELD_TYPE_MATTERS
4696 /* An unnamed bitfield does not normally affect the
4697 alignment of the containing class on a target where
4698 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4699 make any exceptions for unnamed bitfields when the
4700 bitfields are longer than their types. Therefore, we
4701 temporarily give the field a name. */
4702 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4704 was_unnamed_p = true;
4705 DECL_NAME (field) = make_anon_name ();
4708 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4709 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4710 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4711 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4712 empty_base_offsets);
4714 DECL_NAME (field) = NULL_TREE;
4715 /* Now that layout has been performed, set the size of the
4716 field to the size of its declared type; the rest of the
4717 field is effectively invisible. */
4718 DECL_SIZE (field) = TYPE_SIZE (type);
4719 /* We must also reset the DECL_MODE of the field. */
4720 if (abi_version_at_least (2))
4721 DECL_MODE (field) = TYPE_MODE (type);
4723 && DECL_MODE (field) != TYPE_MODE (type))
4724 /* Versions of G++ before G++ 3.4 did not reset the
4727 "the offset of %qD may not be ABI-compliant and may "
4728 "change in a future version of GCC", field);
4731 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4732 empty_base_offsets);
4734 /* Remember the location of any empty classes in FIELD. */
4735 if (abi_version_at_least (2))
4736 record_subobject_offsets (TREE_TYPE (field),
4737 byte_position(field),
4739 /*is_data_member=*/true);
4741 /* If a bit-field does not immediately follow another bit-field,
4742 and yet it starts in the middle of a byte, we have failed to
4743 comply with the ABI. */
4745 && DECL_C_BIT_FIELD (field)
4746 /* The TREE_NO_WARNING flag gets set by Objective-C when
4747 laying out an Objective-C class. The ObjC ABI differs
4748 from the C++ ABI, and so we do not want a warning
4750 && !TREE_NO_WARNING (field)
4751 && !last_field_was_bitfield
4752 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
4753 DECL_FIELD_BIT_OFFSET (field),
4754 bitsize_unit_node)))
4755 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
4756 "change in a future version of GCC", field);
4758 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
4759 offset of the field. */
4761 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
4762 byte_position (field))
4763 && contains_empty_class_p (TREE_TYPE (field)))
4764 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
4765 "classes to be placed at different locations in a "
4766 "future version of GCC", field);
4768 /* The middle end uses the type of expressions to determine the
4769 possible range of expression values. In order to optimize
4770 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
4771 must be made aware of the width of "i", via its type.
4773 Because C++ does not have integer types of arbitrary width,
4774 we must (for the purposes of the front end) convert from the
4775 type assigned here to the declared type of the bitfield
4776 whenever a bitfield expression is used as an rvalue.
4777 Similarly, when assigning a value to a bitfield, the value
4778 must be converted to the type given the bitfield here. */
4779 if (DECL_C_BIT_FIELD (field))
4782 unsigned HOST_WIDE_INT width;
4783 ftype = TREE_TYPE (field);
4784 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
4785 if (width != TYPE_PRECISION (ftype))
4787 = c_build_bitfield_integer_type (width,
4788 TYPE_UNSIGNED (ftype));
4791 /* If we needed additional padding after this field, add it
4797 padding_field = build_decl (FIELD_DECL,
4800 DECL_BIT_FIELD (padding_field) = 1;
4801 DECL_SIZE (padding_field) = padding;
4802 DECL_CONTEXT (padding_field) = t;
4803 DECL_ARTIFICIAL (padding_field) = 1;
4804 DECL_IGNORED_P (padding_field) = 1;
4805 layout_nonempty_base_or_field (rli, padding_field,
4807 empty_base_offsets);
4810 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
4813 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
4815 /* Make sure that we are on a byte boundary so that the size of
4816 the class without virtual bases will always be a round number
4818 rli->bitpos = round_up (rli->bitpos, BITS_PER_UNIT);
4819 normalize_rli (rli);
4822 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
4824 if (!abi_version_at_least (2))
4825 include_empty_classes(rli);
4827 /* Delete all zero-width bit-fields from the list of fields. Now
4828 that the type is laid out they are no longer important. */
4829 remove_zero_width_bit_fields (t);
4831 /* Create the version of T used for virtual bases. We do not use
4832 make_aggr_type for this version; this is an artificial type. For
4833 a POD type, we just reuse T. */
4834 if (CLASSTYPE_NON_POD_P (t) || CLASSTYPE_EMPTY_P (t))
4836 base_t = make_node (TREE_CODE (t));
4838 /* Set the size and alignment for the new type. In G++ 3.2, all
4839 empty classes were considered to have size zero when used as
4841 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
4843 TYPE_SIZE (base_t) = bitsize_zero_node;
4844 TYPE_SIZE_UNIT (base_t) = size_zero_node;
4845 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
4847 "layout of classes derived from empty class %qT "
4848 "may change in a future version of GCC",
4855 /* If the ABI version is not at least two, and the last
4856 field was a bit-field, RLI may not be on a byte
4857 boundary. In particular, rli_size_unit_so_far might
4858 indicate the last complete byte, while rli_size_so_far
4859 indicates the total number of bits used. Therefore,
4860 rli_size_so_far, rather than rli_size_unit_so_far, is
4861 used to compute TYPE_SIZE_UNIT. */
4862 eoc = end_of_class (t, /*include_virtuals_p=*/0);
4863 TYPE_SIZE_UNIT (base_t)
4864 = size_binop (MAX_EXPR,
4866 size_binop (CEIL_DIV_EXPR,
4867 rli_size_so_far (rli),
4868 bitsize_int (BITS_PER_UNIT))),
4871 = size_binop (MAX_EXPR,
4872 rli_size_so_far (rli),
4873 size_binop (MULT_EXPR,
4874 convert (bitsizetype, eoc),
4875 bitsize_int (BITS_PER_UNIT)));
4877 TYPE_ALIGN (base_t) = rli->record_align;
4878 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
4880 /* Copy the fields from T. */
4881 next_field = &TYPE_FIELDS (base_t);
4882 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4883 if (TREE_CODE (field) == FIELD_DECL)
4885 *next_field = build_decl (FIELD_DECL,
4888 DECL_CONTEXT (*next_field) = base_t;
4889 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
4890 DECL_FIELD_BIT_OFFSET (*next_field)
4891 = DECL_FIELD_BIT_OFFSET (field);
4892 DECL_SIZE (*next_field) = DECL_SIZE (field);
4893 DECL_MODE (*next_field) = DECL_MODE (field);
4894 next_field = &TREE_CHAIN (*next_field);
4897 /* Record the base version of the type. */
4898 CLASSTYPE_AS_BASE (t) = base_t;
4899 TYPE_CONTEXT (base_t) = t;
4902 CLASSTYPE_AS_BASE (t) = t;
4904 /* Every empty class contains an empty class. */
4905 if (CLASSTYPE_EMPTY_P (t))
4906 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
4908 /* Set the TYPE_DECL for this type to contain the right
4909 value for DECL_OFFSET, so that we can use it as part
4910 of a COMPONENT_REF for multiple inheritance. */
4911 layout_decl (TYPE_MAIN_DECL (t), 0);
4913 /* Now fix up any virtual base class types that we left lying
4914 around. We must get these done before we try to lay out the
4915 virtual function table. As a side-effect, this will remove the
4916 base subobject fields. */
4917 layout_virtual_bases (rli, empty_base_offsets);
4919 /* Make sure that empty classes are reflected in RLI at this
4921 include_empty_classes(rli);
4923 /* Make sure not to create any structures with zero size. */
4924 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
4926 build_decl (FIELD_DECL, NULL_TREE, char_type_node));
4928 /* Let the back end lay out the type. */
4929 finish_record_layout (rli, /*free_p=*/true);
4931 /* Warn about bases that can't be talked about due to ambiguity. */
4932 warn_about_ambiguous_bases (t);
4934 /* Now that we're done with layout, give the base fields the real types. */
4935 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4936 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
4937 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
4940 splay_tree_delete (empty_base_offsets);
4942 if (CLASSTYPE_EMPTY_P (t)
4943 && tree_int_cst_lt (sizeof_biggest_empty_class,
4944 TYPE_SIZE_UNIT (t)))
4945 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
4948 /* Determine the "key method" for the class type indicated by TYPE,
4949 and set CLASSTYPE_KEY_METHOD accordingly. */
4952 determine_key_method (tree type)
4956 if (TYPE_FOR_JAVA (type)
4957 || processing_template_decl
4958 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
4959 || CLASSTYPE_INTERFACE_KNOWN (type))
4962 /* The key method is the first non-pure virtual function that is not
4963 inline at the point of class definition. On some targets the
4964 key function may not be inline; those targets should not call
4965 this function until the end of the translation unit. */
4966 for (method = TYPE_METHODS (type); method != NULL_TREE;
4967 method = TREE_CHAIN (method))
4968 if (DECL_VINDEX (method) != NULL_TREE
4969 && ! DECL_DECLARED_INLINE_P (method)
4970 && ! DECL_PURE_VIRTUAL_P (method))
4972 CLASSTYPE_KEY_METHOD (type) = method;
4979 /* Perform processing required when the definition of T (a class type)
4983 finish_struct_1 (tree t)
4986 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
4987 tree virtuals = NULL_TREE;
4990 if (COMPLETE_TYPE_P (t))
4992 gcc_assert (IS_AGGR_TYPE (t));
4993 error ("redefinition of %q#T", t);
4998 /* If this type was previously laid out as a forward reference,
4999 make sure we lay it out again. */
5000 TYPE_SIZE (t) = NULL_TREE;
5001 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5003 fixup_inline_methods (t);
5005 /* Make assumptions about the class; we'll reset the flags if
5007 CLASSTYPE_EMPTY_P (t) = 1;
5008 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5009 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5011 /* Do end-of-class semantic processing: checking the validity of the
5012 bases and members and add implicitly generated methods. */
5013 check_bases_and_members (t);
5015 /* Find the key method. */
5016 if (TYPE_CONTAINS_VPTR_P (t))
5018 /* The Itanium C++ ABI permits the key method to be chosen when
5019 the class is defined -- even though the key method so
5020 selected may later turn out to be an inline function. On
5021 some systems (such as ARM Symbian OS) the key method cannot
5022 be determined until the end of the translation unit. On such
5023 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5024 will cause the class to be added to KEYED_CLASSES. Then, in
5025 finish_file we will determine the key method. */
5026 if (targetm.cxx.key_method_may_be_inline ())
5027 determine_key_method (t);
5029 /* If a polymorphic class has no key method, we may emit the vtable
5030 in every translation unit where the class definition appears. */
5031 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5032 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5035 /* Layout the class itself. */
5036 layout_class_type (t, &virtuals);
5037 if (CLASSTYPE_AS_BASE (t) != t)
5038 /* We use the base type for trivial assignments, and hence it
5040 compute_record_mode (CLASSTYPE_AS_BASE (t));
5042 virtuals = modify_all_vtables (t, nreverse (virtuals));
5044 /* If necessary, create the primary vtable for this class. */
5045 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5047 /* We must enter these virtuals into the table. */
5048 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5049 build_primary_vtable (NULL_TREE, t);
5050 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5051 /* Here we know enough to change the type of our virtual
5052 function table, but we will wait until later this function. */
5053 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5056 if (TYPE_CONTAINS_VPTR_P (t))
5061 if (BINFO_VTABLE (TYPE_BINFO (t)))
5062 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5063 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5064 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5066 /* Add entries for virtual functions introduced by this class. */
5067 BINFO_VIRTUALS (TYPE_BINFO (t))
5068 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5070 /* Set DECL_VINDEX for all functions declared in this class. */
5071 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5073 fn = TREE_CHAIN (fn),
5074 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5075 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5077 tree fndecl = BV_FN (fn);
5079 if (DECL_THUNK_P (fndecl))
5080 /* A thunk. We should never be calling this entry directly
5081 from this vtable -- we'd use the entry for the non
5082 thunk base function. */
5083 DECL_VINDEX (fndecl) = NULL_TREE;
5084 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5085 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5089 finish_struct_bits (t);
5091 /* Complete the rtl for any static member objects of the type we're
5093 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5094 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5095 && TREE_TYPE (x) != error_mark_node
5096 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5097 DECL_MODE (x) = TYPE_MODE (t);
5099 /* Done with FIELDS...now decide whether to sort these for
5100 faster lookups later.
5102 We use a small number because most searches fail (succeeding
5103 ultimately as the search bores through the inheritance
5104 hierarchy), and we want this failure to occur quickly. */
5106 n_fields = count_fields (TYPE_FIELDS (t));
5109 struct sorted_fields_type *field_vec = GGC_NEWVAR
5110 (struct sorted_fields_type,
5111 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5112 field_vec->len = n_fields;
5113 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5114 qsort (field_vec->elts, n_fields, sizeof (tree),
5116 if (! DECL_LANG_SPECIFIC (TYPE_MAIN_DECL (t)))
5117 retrofit_lang_decl (TYPE_MAIN_DECL (t));
5118 DECL_SORTED_FIELDS (TYPE_MAIN_DECL (t)) = field_vec;
5121 /* Complain if one of the field types requires lower visibility. */
5122 constrain_class_visibility (t);
5124 /* Make the rtl for any new vtables we have created, and unmark
5125 the base types we marked. */
5128 /* Build the VTT for T. */
5131 /* This warning does not make sense for Java classes, since they
5132 cannot have destructors. */
5133 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5137 dtor = CLASSTYPE_DESTRUCTORS (t);
5138 if (/* An implicitly declared destructor is always public. And,
5139 if it were virtual, we would have created it by now. */
5141 || (!DECL_VINDEX (dtor)
5142 && (/* public non-virtual */
5143 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5144 || (/* non-public non-virtual with friends */
5145 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5146 && (CLASSTYPE_FRIEND_CLASSES (t)
5147 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5148 warning (OPT_Wnon_virtual_dtor,
5149 "%q#T has virtual functions and accessible"
5150 " non-virtual destructor", t);
5155 if (warn_overloaded_virtual)
5158 /* Class layout, assignment of virtual table slots, etc., is now
5159 complete. Give the back end a chance to tweak the visibility of
5160 the class or perform any other required target modifications. */
5161 targetm.cxx.adjust_class_at_definition (t);
5163 maybe_suppress_debug_info (t);
5165 dump_class_hierarchy (t);
5167 /* Finish debugging output for this type. */
5168 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5171 /* When T was built up, the member declarations were added in reverse
5172 order. Rearrange them to declaration order. */
5175 unreverse_member_declarations (tree t)
5181 /* The following lists are all in reverse order. Put them in
5182 declaration order now. */
5183 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5184 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5186 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5187 reverse order, so we can't just use nreverse. */
5189 for (x = TYPE_FIELDS (t);
5190 x && TREE_CODE (x) != TYPE_DECL;
5193 next = TREE_CHAIN (x);
5194 TREE_CHAIN (x) = prev;
5199 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5201 TYPE_FIELDS (t) = prev;
5206 finish_struct (tree t, tree attributes)
5208 location_t saved_loc = input_location;
5210 /* Now that we've got all the field declarations, reverse everything
5212 unreverse_member_declarations (t);
5214 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5216 /* Nadger the current location so that diagnostics point to the start of
5217 the struct, not the end. */
5218 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5220 if (processing_template_decl)
5224 finish_struct_methods (t);
5225 TYPE_SIZE (t) = bitsize_zero_node;
5226 TYPE_SIZE_UNIT (t) = size_zero_node;
5228 /* We need to emit an error message if this type was used as a parameter
5229 and it is an abstract type, even if it is a template. We construct
5230 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5231 account and we call complete_vars with this type, which will check
5232 the PARM_DECLS. Note that while the type is being defined,
5233 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5234 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5235 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5236 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5237 if (DECL_PURE_VIRTUAL_P (x))
5238 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5242 finish_struct_1 (t);
5244 input_location = saved_loc;
5246 TYPE_BEING_DEFINED (t) = 0;
5248 if (current_class_type)
5251 error ("trying to finish struct, but kicked out due to previous parse errors");
5253 if (processing_template_decl && at_function_scope_p ())
5254 add_stmt (build_min (TAG_DEFN, t));
5259 /* Return the dynamic type of INSTANCE, if known.
5260 Used to determine whether the virtual function table is needed
5263 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5264 of our knowledge of its type. *NONNULL should be initialized
5265 before this function is called. */
5268 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5270 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5272 switch (TREE_CODE (instance))
5275 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5278 return RECUR (TREE_OPERAND (instance, 0));
5281 /* This is a call to a constructor, hence it's never zero. */
5282 if (TREE_HAS_CONSTRUCTOR (instance))
5286 return TREE_TYPE (instance);
5291 /* This is a call to a constructor, hence it's never zero. */
5292 if (TREE_HAS_CONSTRUCTOR (instance))
5296 return TREE_TYPE (instance);
5298 return RECUR (TREE_OPERAND (instance, 0));
5300 case POINTER_PLUS_EXPR:
5303 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5304 return RECUR (TREE_OPERAND (instance, 0));
5305 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5306 /* Propagate nonnull. */
5307 return RECUR (TREE_OPERAND (instance, 0));
5313 return RECUR (TREE_OPERAND (instance, 0));
5316 instance = TREE_OPERAND (instance, 0);
5319 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5320 with a real object -- given &p->f, p can still be null. */
5321 tree t = get_base_address (instance);
5322 /* ??? Probably should check DECL_WEAK here. */
5323 if (t && DECL_P (t))
5326 return RECUR (instance);
5329 /* If this component is really a base class reference, then the field
5330 itself isn't definitive. */
5331 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5332 return RECUR (TREE_OPERAND (instance, 0));
5333 return RECUR (TREE_OPERAND (instance, 1));
5337 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5338 && IS_AGGR_TYPE (TREE_TYPE (TREE_TYPE (instance))))
5342 return TREE_TYPE (TREE_TYPE (instance));
5344 /* fall through... */
5348 if (IS_AGGR_TYPE (TREE_TYPE (instance)))
5352 return TREE_TYPE (instance);
5354 else if (instance == current_class_ptr)
5359 /* if we're in a ctor or dtor, we know our type. */
5360 if (DECL_LANG_SPECIFIC (current_function_decl)
5361 && (DECL_CONSTRUCTOR_P (current_function_decl)
5362 || DECL_DESTRUCTOR_P (current_function_decl)))
5366 return TREE_TYPE (TREE_TYPE (instance));
5369 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5371 /* We only need one hash table because it is always left empty. */
5374 ht = htab_create (37,
5379 /* Reference variables should be references to objects. */
5383 /* Enter the INSTANCE in a table to prevent recursion; a
5384 variable's initializer may refer to the variable
5386 if (TREE_CODE (instance) == VAR_DECL
5387 && DECL_INITIAL (instance)
5388 && !htab_find (ht, instance))
5393 slot = htab_find_slot (ht, instance, INSERT);
5395 type = RECUR (DECL_INITIAL (instance));
5396 htab_remove_elt (ht, instance);
5409 /* Return nonzero if the dynamic type of INSTANCE is known, and
5410 equivalent to the static type. We also handle the case where
5411 INSTANCE is really a pointer. Return negative if this is a
5412 ctor/dtor. There the dynamic type is known, but this might not be
5413 the most derived base of the original object, and hence virtual
5414 bases may not be layed out according to this type.
5416 Used to determine whether the virtual function table is needed
5419 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5420 of our knowledge of its type. *NONNULL should be initialized
5421 before this function is called. */
5424 resolves_to_fixed_type_p (tree instance, int* nonnull)
5426 tree t = TREE_TYPE (instance);
5428 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5429 if (fixed == NULL_TREE)
5431 if (POINTER_TYPE_P (t))
5433 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5435 return cdtorp ? -1 : 1;
5440 init_class_processing (void)
5442 current_class_depth = 0;
5443 current_class_stack_size = 10;
5445 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5446 local_classes = VEC_alloc (tree, gc, 8);
5447 sizeof_biggest_empty_class = size_zero_node;
5449 ridpointers[(int) RID_PUBLIC] = access_public_node;
5450 ridpointers[(int) RID_PRIVATE] = access_private_node;
5451 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5454 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5457 restore_class_cache (void)
5461 /* We are re-entering the same class we just left, so we don't
5462 have to search the whole inheritance matrix to find all the
5463 decls to bind again. Instead, we install the cached
5464 class_shadowed list and walk through it binding names. */
5465 push_binding_level (previous_class_level);
5466 class_binding_level = previous_class_level;
5467 /* Restore IDENTIFIER_TYPE_VALUE. */
5468 for (type = class_binding_level->type_shadowed;
5470 type = TREE_CHAIN (type))
5471 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5474 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5475 appropriate for TYPE.
5477 So that we may avoid calls to lookup_name, we cache the _TYPE
5478 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5480 For multiple inheritance, we perform a two-pass depth-first search
5481 of the type lattice. */
5484 pushclass (tree type)
5486 class_stack_node_t csn;
5488 type = TYPE_MAIN_VARIANT (type);
5490 /* Make sure there is enough room for the new entry on the stack. */
5491 if (current_class_depth + 1 >= current_class_stack_size)
5493 current_class_stack_size *= 2;
5495 = XRESIZEVEC (struct class_stack_node, current_class_stack,
5496 current_class_stack_size);
5499 /* Insert a new entry on the class stack. */
5500 csn = current_class_stack + current_class_depth;
5501 csn->name = current_class_name;
5502 csn->type = current_class_type;
5503 csn->access = current_access_specifier;
5504 csn->names_used = 0;
5506 current_class_depth++;
5508 /* Now set up the new type. */
5509 current_class_name = TYPE_NAME (type);
5510 if (TREE_CODE (current_class_name) == TYPE_DECL)
5511 current_class_name = DECL_NAME (current_class_name);
5512 current_class_type = type;
5514 /* By default, things in classes are private, while things in
5515 structures or unions are public. */
5516 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5517 ? access_private_node
5518 : access_public_node);
5520 if (previous_class_level
5521 && type != previous_class_level->this_entity
5522 && current_class_depth == 1)
5524 /* Forcibly remove any old class remnants. */
5525 invalidate_class_lookup_cache ();
5528 if (!previous_class_level
5529 || type != previous_class_level->this_entity
5530 || current_class_depth > 1)
5533 restore_class_cache ();
5536 /* When we exit a toplevel class scope, we save its binding level so
5537 that we can restore it quickly. Here, we've entered some other
5538 class, so we must invalidate our cache. */
5541 invalidate_class_lookup_cache (void)
5543 previous_class_level = NULL;
5546 /* Get out of the current class scope. If we were in a class scope
5547 previously, that is the one popped to. */
5554 current_class_depth--;
5555 current_class_name = current_class_stack[current_class_depth].name;
5556 current_class_type = current_class_stack[current_class_depth].type;
5557 current_access_specifier = current_class_stack[current_class_depth].access;
5558 if (current_class_stack[current_class_depth].names_used)
5559 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5562 /* Mark the top of the class stack as hidden. */
5565 push_class_stack (void)
5567 if (current_class_depth)
5568 ++current_class_stack[current_class_depth - 1].hidden;
5571 /* Mark the top of the class stack as un-hidden. */
5574 pop_class_stack (void)
5576 if (current_class_depth)
5577 --current_class_stack[current_class_depth - 1].hidden;
5580 /* Returns 1 if the class type currently being defined is either T or
5581 a nested type of T. */
5584 currently_open_class (tree t)
5588 /* We start looking from 1 because entry 0 is from global scope,
5590 for (i = current_class_depth; i > 0; --i)
5593 if (i == current_class_depth)
5594 c = current_class_type;
5597 if (current_class_stack[i].hidden)
5599 c = current_class_stack[i].type;
5603 if (same_type_p (c, t))
5609 /* If either current_class_type or one of its enclosing classes are derived
5610 from T, return the appropriate type. Used to determine how we found
5611 something via unqualified lookup. */
5614 currently_open_derived_class (tree t)
5618 /* The bases of a dependent type are unknown. */
5619 if (dependent_type_p (t))
5622 if (!current_class_type)
5625 if (DERIVED_FROM_P (t, current_class_type))
5626 return current_class_type;
5628 for (i = current_class_depth - 1; i > 0; --i)
5630 if (current_class_stack[i].hidden)
5632 if (DERIVED_FROM_P (t, current_class_stack[i].type))
5633 return current_class_stack[i].type;
5639 /* When entering a class scope, all enclosing class scopes' names with
5640 static meaning (static variables, static functions, types and
5641 enumerators) have to be visible. This recursive function calls
5642 pushclass for all enclosing class contexts until global or a local
5643 scope is reached. TYPE is the enclosed class. */
5646 push_nested_class (tree type)
5650 /* A namespace might be passed in error cases, like A::B:C. */
5651 if (type == NULL_TREE
5652 || type == error_mark_node
5653 || TREE_CODE (type) == NAMESPACE_DECL
5654 || ! IS_AGGR_TYPE (type)
5655 || TREE_CODE (type) == TEMPLATE_TYPE_PARM
5656 || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
5659 context = DECL_CONTEXT (TYPE_MAIN_DECL (type));
5661 if (context && CLASS_TYPE_P (context))
5662 push_nested_class (context);
5666 /* Undoes a push_nested_class call. */
5669 pop_nested_class (void)
5671 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5674 if (context && CLASS_TYPE_P (context))
5675 pop_nested_class ();
5678 /* Returns the number of extern "LANG" blocks we are nested within. */
5681 current_lang_depth (void)
5683 return VEC_length (tree, current_lang_base);
5686 /* Set global variables CURRENT_LANG_NAME to appropriate value
5687 so that behavior of name-mangling machinery is correct. */
5690 push_lang_context (tree name)
5692 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
5694 if (name == lang_name_cplusplus)
5696 current_lang_name = name;
5698 else if (name == lang_name_java)
5700 current_lang_name = name;
5701 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5702 (See record_builtin_java_type in decl.c.) However, that causes
5703 incorrect debug entries if these types are actually used.
5704 So we re-enable debug output after extern "Java". */
5705 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
5706 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
5707 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
5708 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
5709 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
5710 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
5711 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
5712 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
5714 else if (name == lang_name_c)
5716 current_lang_name = name;
5719 error ("language string %<\"%E\"%> not recognized", name);
5722 /* Get out of the current language scope. */
5725 pop_lang_context (void)
5727 current_lang_name = VEC_pop (tree, current_lang_base);
5730 /* Type instantiation routines. */
5732 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
5733 matches the TARGET_TYPE. If there is no satisfactory match, return
5734 error_mark_node, and issue an error & warning messages under
5735 control of FLAGS. Permit pointers to member function if FLAGS
5736 permits. If TEMPLATE_ONLY, the name of the overloaded function was
5737 a template-id, and EXPLICIT_TARGS are the explicitly provided
5738 template arguments. If OVERLOAD is for one or more member
5739 functions, then ACCESS_PATH is the base path used to reference
5740 those member functions. */
5743 resolve_address_of_overloaded_function (tree target_type,
5745 tsubst_flags_t flags,
5747 tree explicit_targs,
5750 /* Here's what the standard says:
5754 If the name is a function template, template argument deduction
5755 is done, and if the argument deduction succeeds, the deduced
5756 arguments are used to generate a single template function, which
5757 is added to the set of overloaded functions considered.
5759 Non-member functions and static member functions match targets of
5760 type "pointer-to-function" or "reference-to-function." Nonstatic
5761 member functions match targets of type "pointer-to-member
5762 function;" the function type of the pointer to member is used to
5763 select the member function from the set of overloaded member
5764 functions. If a nonstatic member function is selected, the
5765 reference to the overloaded function name is required to have the
5766 form of a pointer to member as described in 5.3.1.
5768 If more than one function is selected, any template functions in
5769 the set are eliminated if the set also contains a non-template
5770 function, and any given template function is eliminated if the
5771 set contains a second template function that is more specialized
5772 than the first according to the partial ordering rules 14.5.5.2.
5773 After such eliminations, if any, there shall remain exactly one
5774 selected function. */
5777 int is_reference = 0;
5778 /* We store the matches in a TREE_LIST rooted here. The functions
5779 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
5780 interoperability with most_specialized_instantiation. */
5781 tree matches = NULL_TREE;
5784 /* By the time we get here, we should be seeing only real
5785 pointer-to-member types, not the internal POINTER_TYPE to
5786 METHOD_TYPE representation. */
5787 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
5788 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
5790 gcc_assert (is_overloaded_fn (overload));
5792 /* Check that the TARGET_TYPE is reasonable. */
5793 if (TYPE_PTRFN_P (target_type))
5795 else if (TYPE_PTRMEMFUNC_P (target_type))
5796 /* This is OK, too. */
5798 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
5800 /* This is OK, too. This comes from a conversion to reference
5802 target_type = build_reference_type (target_type);
5807 if (flags & tf_error)
5808 error ("cannot resolve overloaded function %qD based on"
5809 " conversion to type %qT",
5810 DECL_NAME (OVL_FUNCTION (overload)), target_type);
5811 return error_mark_node;
5814 /* If we can find a non-template function that matches, we can just
5815 use it. There's no point in generating template instantiations
5816 if we're just going to throw them out anyhow. But, of course, we
5817 can only do this when we don't *need* a template function. */
5822 for (fns = overload; fns; fns = OVL_NEXT (fns))
5824 tree fn = OVL_CURRENT (fns);
5827 if (TREE_CODE (fn) == TEMPLATE_DECL)
5828 /* We're not looking for templates just yet. */
5831 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5833 /* We're looking for a non-static member, and this isn't
5834 one, or vice versa. */
5837 /* Ignore functions which haven't been explicitly
5839 if (DECL_ANTICIPATED (fn))
5842 /* See if there's a match. */
5843 fntype = TREE_TYPE (fn);
5845 fntype = build_ptrmemfunc_type (build_pointer_type (fntype));
5846 else if (!is_reference)
5847 fntype = build_pointer_type (fntype);
5849 if (can_convert_arg (target_type, fntype, fn, LOOKUP_NORMAL))
5850 matches = tree_cons (fn, NULL_TREE, matches);
5854 /* Now, if we've already got a match (or matches), there's no need
5855 to proceed to the template functions. But, if we don't have a
5856 match we need to look at them, too. */
5859 tree target_fn_type;
5860 tree target_arg_types;
5861 tree target_ret_type;
5866 = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (target_type));
5868 target_fn_type = TREE_TYPE (target_type);
5869 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
5870 target_ret_type = TREE_TYPE (target_fn_type);
5872 /* Never do unification on the 'this' parameter. */
5873 if (TREE_CODE (target_fn_type) == METHOD_TYPE)
5874 target_arg_types = TREE_CHAIN (target_arg_types);
5876 for (fns = overload; fns; fns = OVL_NEXT (fns))
5878 tree fn = OVL_CURRENT (fns);
5880 tree instantiation_type;
5883 if (TREE_CODE (fn) != TEMPLATE_DECL)
5884 /* We're only looking for templates. */
5887 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5889 /* We're not looking for a non-static member, and this is
5890 one, or vice versa. */
5893 /* Try to do argument deduction. */
5894 targs = make_tree_vec (DECL_NTPARMS (fn));
5895 if (fn_type_unification (fn, explicit_targs, targs,
5896 target_arg_types, target_ret_type,
5897 DEDUCE_EXACT, LOOKUP_NORMAL))
5898 /* Argument deduction failed. */
5901 /* Instantiate the template. */
5902 instantiation = instantiate_template (fn, targs, flags);
5903 if (instantiation == error_mark_node)
5904 /* Instantiation failed. */
5907 /* See if there's a match. */
5908 instantiation_type = TREE_TYPE (instantiation);
5910 instantiation_type =
5911 build_ptrmemfunc_type (build_pointer_type (instantiation_type));
5912 else if (!is_reference)
5913 instantiation_type = build_pointer_type (instantiation_type);
5914 if (can_convert_arg (target_type, instantiation_type, instantiation,
5916 matches = tree_cons (instantiation, fn, matches);
5919 /* Now, remove all but the most specialized of the matches. */
5922 tree match = most_specialized_instantiation (matches);
5924 if (match != error_mark_node)
5925 matches = tree_cons (TREE_PURPOSE (match),
5931 /* Now we should have exactly one function in MATCHES. */
5932 if (matches == NULL_TREE)
5934 /* There were *no* matches. */
5935 if (flags & tf_error)
5937 error ("no matches converting function %qD to type %q#T",
5938 DECL_NAME (OVL_FUNCTION (overload)),
5941 /* print_candidates expects a chain with the functions in
5942 TREE_VALUE slots, so we cons one up here (we're losing anyway,
5943 so why be clever?). */
5944 for (; overload; overload = OVL_NEXT (overload))
5945 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
5948 print_candidates (matches);
5950 return error_mark_node;
5952 else if (TREE_CHAIN (matches))
5954 /* There were too many matches. */
5956 if (flags & tf_error)
5960 error ("converting overloaded function %qD to type %q#T is ambiguous",
5961 DECL_NAME (OVL_FUNCTION (overload)),
5964 /* Since print_candidates expects the functions in the
5965 TREE_VALUE slot, we flip them here. */
5966 for (match = matches; match; match = TREE_CHAIN (match))
5967 TREE_VALUE (match) = TREE_PURPOSE (match);
5969 print_candidates (matches);
5972 return error_mark_node;
5975 /* Good, exactly one match. Now, convert it to the correct type. */
5976 fn = TREE_PURPOSE (matches);
5978 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
5979 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
5981 static int explained;
5983 if (!(flags & tf_error))
5984 return error_mark_node;
5986 pedwarn ("assuming pointer to member %qD", fn);
5989 pedwarn ("(a pointer to member can only be formed with %<&%E%>)", fn);
5994 /* If we're doing overload resolution purely for the purpose of
5995 determining conversion sequences, we should not consider the
5996 function used. If this conversion sequence is selected, the
5997 function will be marked as used at this point. */
5998 if (!(flags & tf_conv))
6001 /* We could not check access when this expression was originally
6002 created since we did not know at that time to which function
6003 the expression referred. */
6004 if (DECL_FUNCTION_MEMBER_P (fn))
6006 gcc_assert (access_path);
6007 perform_or_defer_access_check (access_path, fn, fn);
6011 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6012 return build_unary_op (ADDR_EXPR, fn, 0);
6015 /* The target must be a REFERENCE_TYPE. Above, build_unary_op
6016 will mark the function as addressed, but here we must do it
6018 cxx_mark_addressable (fn);
6024 /* This function will instantiate the type of the expression given in
6025 RHS to match the type of LHSTYPE. If errors exist, then return
6026 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6027 we complain on errors. If we are not complaining, never modify rhs,
6028 as overload resolution wants to try many possible instantiations, in
6029 the hope that at least one will work.
6031 For non-recursive calls, LHSTYPE should be a function, pointer to
6032 function, or a pointer to member function. */
6035 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6037 tsubst_flags_t flags_in = flags;
6038 tree access_path = NULL_TREE;
6040 flags &= ~tf_ptrmem_ok;
6042 if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
6044 if (flags & tf_error)
6045 error ("not enough type information");
6046 return error_mark_node;
6049 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6051 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6053 if (flag_ms_extensions
6054 && TYPE_PTRMEMFUNC_P (lhstype)
6055 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6056 /* Microsoft allows `A::f' to be resolved to a
6057 pointer-to-member. */
6061 if (flags & tf_error)
6062 error ("argument of type %qT does not match %qT",
6063 TREE_TYPE (rhs), lhstype);
6064 return error_mark_node;
6068 if (TREE_CODE (rhs) == BASELINK)
6070 access_path = BASELINK_ACCESS_BINFO (rhs);
6071 rhs = BASELINK_FUNCTIONS (rhs);
6074 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6075 deduce any type information. */
6076 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6078 if (flags & tf_error)
6079 error ("not enough type information");
6080 return error_mark_node;
6083 /* There only a few kinds of expressions that may have a type
6084 dependent on overload resolution. */
6085 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6086 || TREE_CODE (rhs) == COMPONENT_REF
6087 || TREE_CODE (rhs) == COMPOUND_EXPR
6088 || really_overloaded_fn (rhs));
6090 /* We don't overwrite rhs if it is an overloaded function.
6091 Copying it would destroy the tree link. */
6092 if (TREE_CODE (rhs) != OVERLOAD)
6093 rhs = copy_node (rhs);
6095 /* This should really only be used when attempting to distinguish
6096 what sort of a pointer to function we have. For now, any
6097 arithmetic operation which is not supported on pointers
6098 is rejected as an error. */
6100 switch (TREE_CODE (rhs))
6104 tree member = TREE_OPERAND (rhs, 1);
6106 member = instantiate_type (lhstype, member, flags);
6107 if (member != error_mark_node
6108 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6109 /* Do not lose object's side effects. */
6110 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6111 TREE_OPERAND (rhs, 0), member);
6116 rhs = TREE_OPERAND (rhs, 1);
6117 if (BASELINK_P (rhs))
6118 return instantiate_type (lhstype, rhs, flags_in);
6120 /* This can happen if we are forming a pointer-to-member for a
6122 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6126 case TEMPLATE_ID_EXPR:
6128 tree fns = TREE_OPERAND (rhs, 0);
6129 tree args = TREE_OPERAND (rhs, 1);
6132 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6133 /*template_only=*/true,
6140 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6141 /*template_only=*/false,
6142 /*explicit_targs=*/NULL_TREE,
6146 TREE_OPERAND (rhs, 0)
6147 = instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6148 if (TREE_OPERAND (rhs, 0) == error_mark_node)
6149 return error_mark_node;
6150 TREE_OPERAND (rhs, 1)
6151 = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags);
6152 if (TREE_OPERAND (rhs, 1) == error_mark_node)
6153 return error_mark_node;
6155 TREE_TYPE (rhs) = lhstype;
6160 if (PTRMEM_OK_P (rhs))
6161 flags |= tf_ptrmem_ok;
6163 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6167 return error_mark_node;
6172 return error_mark_node;
6175 /* Return the name of the virtual function pointer field
6176 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6177 this may have to look back through base types to find the
6178 ultimate field name. (For single inheritance, these could
6179 all be the same name. Who knows for multiple inheritance). */
6182 get_vfield_name (tree type)
6184 tree binfo, base_binfo;
6187 for (binfo = TYPE_BINFO (type);
6188 BINFO_N_BASE_BINFOS (binfo);
6191 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6193 if (BINFO_VIRTUAL_P (base_binfo)
6194 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6198 type = BINFO_TYPE (binfo);
6199 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6200 + TYPE_NAME_LENGTH (type) + 2);
6201 sprintf (buf, VFIELD_NAME_FORMAT,
6202 IDENTIFIER_POINTER (constructor_name (type)));
6203 return get_identifier (buf);
6207 print_class_statistics (void)
6209 #ifdef GATHER_STATISTICS
6210 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6211 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6214 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6215 n_vtables, n_vtable_searches);
6216 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6217 n_vtable_entries, n_vtable_elems);
6222 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6223 according to [class]:
6224 The class-name is also inserted
6225 into the scope of the class itself. For purposes of access checking,
6226 the inserted class name is treated as if it were a public member name. */
6229 build_self_reference (void)
6231 tree name = constructor_name (current_class_type);
6232 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6235 DECL_NONLOCAL (value) = 1;
6236 DECL_CONTEXT (value) = current_class_type;
6237 DECL_ARTIFICIAL (value) = 1;
6238 SET_DECL_SELF_REFERENCE_P (value);
6240 if (processing_template_decl)
6241 value = push_template_decl (value);
6243 saved_cas = current_access_specifier;
6244 current_access_specifier = access_public_node;
6245 finish_member_declaration (value);
6246 current_access_specifier = saved_cas;
6249 /* Returns 1 if TYPE contains only padding bytes. */
6252 is_empty_class (tree type)
6254 if (type == error_mark_node)
6257 if (! IS_AGGR_TYPE (type))
6260 /* In G++ 3.2, whether or not a class was empty was determined by
6261 looking at its size. */
6262 if (abi_version_at_least (2))
6263 return CLASSTYPE_EMPTY_P (type);
6265 return integer_zerop (CLASSTYPE_SIZE (type));
6268 /* Returns true if TYPE contains an empty class. */
6271 contains_empty_class_p (tree type)
6273 if (is_empty_class (type))
6275 if (CLASS_TYPE_P (type))
6282 for (binfo = TYPE_BINFO (type), i = 0;
6283 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6284 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6286 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6287 if (TREE_CODE (field) == FIELD_DECL
6288 && !DECL_ARTIFICIAL (field)
6289 && is_empty_class (TREE_TYPE (field)))
6292 else if (TREE_CODE (type) == ARRAY_TYPE)
6293 return contains_empty_class_p (TREE_TYPE (type));
6297 /* Note that NAME was looked up while the current class was being
6298 defined and that the result of that lookup was DECL. */
6301 maybe_note_name_used_in_class (tree name, tree decl)
6303 splay_tree names_used;
6305 /* If we're not defining a class, there's nothing to do. */
6306 if (!(innermost_scope_kind() == sk_class
6307 && TYPE_BEING_DEFINED (current_class_type)))
6310 /* If there's already a binding for this NAME, then we don't have
6311 anything to worry about. */
6312 if (lookup_member (current_class_type, name,
6313 /*protect=*/0, /*want_type=*/false))
6316 if (!current_class_stack[current_class_depth - 1].names_used)
6317 current_class_stack[current_class_depth - 1].names_used
6318 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6319 names_used = current_class_stack[current_class_depth - 1].names_used;
6321 splay_tree_insert (names_used,
6322 (splay_tree_key) name,
6323 (splay_tree_value) decl);
6326 /* Note that NAME was declared (as DECL) in the current class. Check
6327 to see that the declaration is valid. */
6330 note_name_declared_in_class (tree name, tree decl)
6332 splay_tree names_used;
6335 /* Look to see if we ever used this name. */
6337 = current_class_stack[current_class_depth - 1].names_used;
6341 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6344 /* [basic.scope.class]
6346 A name N used in a class S shall refer to the same declaration
6347 in its context and when re-evaluated in the completed scope of
6349 pedwarn ("declaration of %q#D", decl);
6350 pedwarn ("changes meaning of %qD from %q+#D",
6351 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6355 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6356 Secondary vtables are merged with primary vtables; this function
6357 will return the VAR_DECL for the primary vtable. */
6360 get_vtbl_decl_for_binfo (tree binfo)
6364 decl = BINFO_VTABLE (binfo);
6365 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
6367 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6368 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6371 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6376 /* Returns the binfo for the primary base of BINFO. If the resulting
6377 BINFO is a virtual base, and it is inherited elsewhere in the
6378 hierarchy, then the returned binfo might not be the primary base of
6379 BINFO in the complete object. Check BINFO_PRIMARY_P or
6380 BINFO_LOST_PRIMARY_P to be sure. */
6383 get_primary_binfo (tree binfo)
6387 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6391 return copied_binfo (primary_base, binfo);
6394 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6397 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6400 fprintf (stream, "%*s", indent, "");
6404 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6405 INDENT should be zero when called from the top level; it is
6406 incremented recursively. IGO indicates the next expected BINFO in
6407 inheritance graph ordering. */
6410 dump_class_hierarchy_r (FILE *stream,
6420 indented = maybe_indent_hierarchy (stream, indent, 0);
6421 fprintf (stream, "%s (0x%lx) ",
6422 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6423 (unsigned long) binfo);
6426 fprintf (stream, "alternative-path\n");
6429 igo = TREE_CHAIN (binfo);
6431 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6432 tree_low_cst (BINFO_OFFSET (binfo), 0));
6433 if (is_empty_class (BINFO_TYPE (binfo)))
6434 fprintf (stream, " empty");
6435 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6436 fprintf (stream, " nearly-empty");
6437 if (BINFO_VIRTUAL_P (binfo))
6438 fprintf (stream, " virtual");
6439 fprintf (stream, "\n");
6442 if (BINFO_PRIMARY_P (binfo))
6444 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6445 fprintf (stream, " primary-for %s (0x%lx)",
6446 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6447 TFF_PLAIN_IDENTIFIER),
6448 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6450 if (BINFO_LOST_PRIMARY_P (binfo))
6452 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6453 fprintf (stream, " lost-primary");
6456 fprintf (stream, "\n");
6458 if (!(flags & TDF_SLIM))
6462 if (BINFO_SUBVTT_INDEX (binfo))
6464 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6465 fprintf (stream, " subvttidx=%s",
6466 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6467 TFF_PLAIN_IDENTIFIER));
6469 if (BINFO_VPTR_INDEX (binfo))
6471 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6472 fprintf (stream, " vptridx=%s",
6473 expr_as_string (BINFO_VPTR_INDEX (binfo),
6474 TFF_PLAIN_IDENTIFIER));
6476 if (BINFO_VPTR_FIELD (binfo))
6478 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6479 fprintf (stream, " vbaseoffset=%s",
6480 expr_as_string (BINFO_VPTR_FIELD (binfo),
6481 TFF_PLAIN_IDENTIFIER));
6483 if (BINFO_VTABLE (binfo))
6485 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6486 fprintf (stream, " vptr=%s",
6487 expr_as_string (BINFO_VTABLE (binfo),
6488 TFF_PLAIN_IDENTIFIER));
6492 fprintf (stream, "\n");
6495 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6496 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6501 /* Dump the BINFO hierarchy for T. */
6504 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6506 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6507 fprintf (stream, " size=%lu align=%lu\n",
6508 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6509 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6510 fprintf (stream, " base size=%lu base align=%lu\n",
6511 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6513 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6515 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6516 fprintf (stream, "\n");
6519 /* Debug interface to hierarchy dumping. */
6522 debug_class (tree t)
6524 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6528 dump_class_hierarchy (tree t)
6531 FILE *stream = dump_begin (TDI_class, &flags);
6535 dump_class_hierarchy_1 (stream, flags, t);
6536 dump_end (TDI_class, stream);
6541 dump_array (FILE * stream, tree decl)
6544 unsigned HOST_WIDE_INT ix;
6546 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6548 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6550 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6551 fprintf (stream, " %s entries",
6552 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6553 TFF_PLAIN_IDENTIFIER));
6554 fprintf (stream, "\n");
6556 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
6558 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
6559 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
6563 dump_vtable (tree t, tree binfo, tree vtable)
6566 FILE *stream = dump_begin (TDI_class, &flags);
6571 if (!(flags & TDF_SLIM))
6573 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6575 fprintf (stream, "%s for %s",
6576 ctor_vtbl_p ? "Construction vtable" : "Vtable",
6577 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6580 if (!BINFO_VIRTUAL_P (binfo))
6581 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6582 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6584 fprintf (stream, "\n");
6585 dump_array (stream, vtable);
6586 fprintf (stream, "\n");
6589 dump_end (TDI_class, stream);
6593 dump_vtt (tree t, tree vtt)
6596 FILE *stream = dump_begin (TDI_class, &flags);
6601 if (!(flags & TDF_SLIM))
6603 fprintf (stream, "VTT for %s\n",
6604 type_as_string (t, TFF_PLAIN_IDENTIFIER));
6605 dump_array (stream, vtt);
6606 fprintf (stream, "\n");
6609 dump_end (TDI_class, stream);
6612 /* Dump a function or thunk and its thunkees. */
6615 dump_thunk (FILE *stream, int indent, tree thunk)
6617 static const char spaces[] = " ";
6618 tree name = DECL_NAME (thunk);
6621 fprintf (stream, "%.*s%p %s %s", indent, spaces,
6623 !DECL_THUNK_P (thunk) ? "function"
6624 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6625 name ? IDENTIFIER_POINTER (name) : "<unset>");
6626 if (DECL_THUNK_P (thunk))
6628 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6629 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6631 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6632 if (!virtual_adjust)
6634 else if (DECL_THIS_THUNK_P (thunk))
6635 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
6636 tree_low_cst (virtual_adjust, 0));
6638 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6639 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6640 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6641 if (THUNK_ALIAS (thunk))
6642 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6644 fprintf (stream, "\n");
6645 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6646 dump_thunk (stream, indent + 2, thunks);
6649 /* Dump the thunks for FN. */
6652 debug_thunks (tree fn)
6654 dump_thunk (stderr, 0, fn);
6657 /* Virtual function table initialization. */
6659 /* Create all the necessary vtables for T and its base classes. */
6662 finish_vtbls (tree t)
6667 /* We lay out the primary and secondary vtables in one contiguous
6668 vtable. The primary vtable is first, followed by the non-virtual
6669 secondary vtables in inheritance graph order. */
6670 list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6671 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6672 TYPE_BINFO (t), t, list);
6674 /* Then come the virtual bases, also in inheritance graph order. */
6675 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6677 if (!BINFO_VIRTUAL_P (vbase))
6679 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6682 if (BINFO_VTABLE (TYPE_BINFO (t)))
6683 initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
6686 /* Initialize the vtable for BINFO with the INITS. */
6689 initialize_vtable (tree binfo, tree inits)
6693 layout_vtable_decl (binfo, list_length (inits));
6694 decl = get_vtbl_decl_for_binfo (binfo);
6695 initialize_artificial_var (decl, inits);
6696 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
6699 /* Build the VTT (virtual table table) for T.
6700 A class requires a VTT if it has virtual bases.
6703 1 - primary virtual pointer for complete object T
6704 2 - secondary VTTs for each direct non-virtual base of T which requires a
6706 3 - secondary virtual pointers for each direct or indirect base of T which
6707 has virtual bases or is reachable via a virtual path from T.
6708 4 - secondary VTTs for each direct or indirect virtual base of T.
6710 Secondary VTTs look like complete object VTTs without part 4. */
6720 /* Build up the initializers for the VTT. */
6722 index = size_zero_node;
6723 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
6725 /* If we didn't need a VTT, we're done. */
6729 /* Figure out the type of the VTT. */
6730 type = build_index_type (size_int (list_length (inits) - 1));
6731 type = build_cplus_array_type (const_ptr_type_node, type);
6733 /* Now, build the VTT object itself. */
6734 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
6735 initialize_artificial_var (vtt, inits);
6736 /* Add the VTT to the vtables list. */
6737 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
6738 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
6743 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
6744 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
6745 and CHAIN the vtable pointer for this binfo after construction is
6746 complete. VALUE can also be another BINFO, in which case we recurse. */
6749 binfo_ctor_vtable (tree binfo)
6755 vt = BINFO_VTABLE (binfo);
6756 if (TREE_CODE (vt) == TREE_LIST)
6757 vt = TREE_VALUE (vt);
6758 if (TREE_CODE (vt) == TREE_BINFO)
6767 /* Data for secondary VTT initialization. */
6768 typedef struct secondary_vptr_vtt_init_data_s
6770 /* Is this the primary VTT? */
6773 /* Current index into the VTT. */
6776 /* TREE_LIST of initializers built up. */
6779 /* The type being constructed by this secondary VTT. */
6780 tree type_being_constructed;
6781 } secondary_vptr_vtt_init_data;
6783 /* Recursively build the VTT-initializer for BINFO (which is in the
6784 hierarchy dominated by T). INITS points to the end of the initializer
6785 list to date. INDEX is the VTT index where the next element will be
6786 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
6787 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
6788 for virtual bases of T. When it is not so, we build the constructor
6789 vtables for the BINFO-in-T variant. */
6792 build_vtt_inits (tree binfo, tree t, tree *inits, tree *index)
6797 tree secondary_vptrs;
6798 secondary_vptr_vtt_init_data data;
6799 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
6801 /* We only need VTTs for subobjects with virtual bases. */
6802 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
6805 /* We need to use a construction vtable if this is not the primary
6809 build_ctor_vtbl_group (binfo, t);
6811 /* Record the offset in the VTT where this sub-VTT can be found. */
6812 BINFO_SUBVTT_INDEX (binfo) = *index;
6815 /* Add the address of the primary vtable for the complete object. */
6816 init = binfo_ctor_vtable (binfo);
6817 *inits = build_tree_list (NULL_TREE, init);
6818 inits = &TREE_CHAIN (*inits);
6821 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6822 BINFO_VPTR_INDEX (binfo) = *index;
6824 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
6826 /* Recursively add the secondary VTTs for non-virtual bases. */
6827 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
6828 if (!BINFO_VIRTUAL_P (b))
6829 inits = build_vtt_inits (b, t, inits, index);
6831 /* Add secondary virtual pointers for all subobjects of BINFO with
6832 either virtual bases or reachable along a virtual path, except
6833 subobjects that are non-virtual primary bases. */
6834 data.top_level_p = top_level_p;
6835 data.index = *index;
6837 data.type_being_constructed = BINFO_TYPE (binfo);
6839 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
6841 *index = data.index;
6843 /* The secondary vptrs come back in reverse order. After we reverse
6844 them, and add the INITS, the last init will be the first element
6846 secondary_vptrs = data.inits;
6847 if (secondary_vptrs)
6849 *inits = nreverse (secondary_vptrs);
6850 inits = &TREE_CHAIN (secondary_vptrs);
6851 gcc_assert (*inits == NULL_TREE);
6855 /* Add the secondary VTTs for virtual bases in inheritance graph
6857 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
6859 if (!BINFO_VIRTUAL_P (b))
6862 inits = build_vtt_inits (b, t, inits, index);
6865 /* Remove the ctor vtables we created. */
6866 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
6871 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
6872 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
6875 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
6877 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
6879 /* We don't care about bases that don't have vtables. */
6880 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
6881 return dfs_skip_bases;
6883 /* We're only interested in proper subobjects of the type being
6885 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
6888 /* We're only interested in bases with virtual bases or reachable
6889 via a virtual path from the type being constructed. */
6890 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
6891 || binfo_via_virtual (binfo, data->type_being_constructed)))
6892 return dfs_skip_bases;
6894 /* We're not interested in non-virtual primary bases. */
6895 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
6898 /* Record the index where this secondary vptr can be found. */
6899 if (data->top_level_p)
6901 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6902 BINFO_VPTR_INDEX (binfo) = data->index;
6904 if (BINFO_VIRTUAL_P (binfo))
6906 /* It's a primary virtual base, and this is not a
6907 construction vtable. Find the base this is primary of in
6908 the inheritance graph, and use that base's vtable
6910 while (BINFO_PRIMARY_P (binfo))
6911 binfo = BINFO_INHERITANCE_CHAIN (binfo);
6915 /* Add the initializer for the secondary vptr itself. */
6916 data->inits = tree_cons (NULL_TREE, binfo_ctor_vtable (binfo), data->inits);
6918 /* Advance the vtt index. */
6919 data->index = size_binop (PLUS_EXPR, data->index,
6920 TYPE_SIZE_UNIT (ptr_type_node));
6925 /* Called from build_vtt_inits via dfs_walk. After building
6926 constructor vtables and generating the sub-vtt from them, we need
6927 to restore the BINFO_VTABLES that were scribbled on. DATA is the
6928 binfo of the base whose sub vtt was generated. */
6931 dfs_fixup_binfo_vtbls (tree binfo, void* data)
6933 tree vtable = BINFO_VTABLE (binfo);
6935 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
6936 /* If this class has no vtable, none of its bases do. */
6937 return dfs_skip_bases;
6940 /* This might be a primary base, so have no vtable in this
6944 /* If we scribbled the construction vtable vptr into BINFO, clear it
6946 if (TREE_CODE (vtable) == TREE_LIST
6947 && (TREE_PURPOSE (vtable) == (tree) data))
6948 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
6953 /* Build the construction vtable group for BINFO which is in the
6954 hierarchy dominated by T. */
6957 build_ctor_vtbl_group (tree binfo, tree t)
6966 /* See if we've already created this construction vtable group. */
6967 id = mangle_ctor_vtbl_for_type (t, binfo);
6968 if (IDENTIFIER_GLOBAL_VALUE (id))
6971 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
6972 /* Build a version of VTBL (with the wrong type) for use in
6973 constructing the addresses of secondary vtables in the
6974 construction vtable group. */
6975 vtbl = build_vtable (t, id, ptr_type_node);
6976 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
6977 list = build_tree_list (vtbl, NULL_TREE);
6978 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
6981 /* Add the vtables for each of our virtual bases using the vbase in T
6983 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
6985 vbase = TREE_CHAIN (vbase))
6989 if (!BINFO_VIRTUAL_P (vbase))
6991 b = copied_binfo (vbase, binfo);
6993 accumulate_vtbl_inits (b, vbase, binfo, t, list);
6995 inits = TREE_VALUE (list);
6997 /* Figure out the type of the construction vtable. */
6998 type = build_index_type (size_int (list_length (inits) - 1));
6999 type = build_cplus_array_type (vtable_entry_type, type);
7000 TREE_TYPE (vtbl) = type;
7002 /* Initialize the construction vtable. */
7003 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7004 initialize_artificial_var (vtbl, inits);
7005 dump_vtable (t, binfo, vtbl);
7008 /* Add the vtbl initializers for BINFO (and its bases other than
7009 non-virtual primaries) to the list of INITS. BINFO is in the
7010 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7011 the constructor the vtbl inits should be accumulated for. (If this
7012 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7013 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7014 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7015 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7016 but are not necessarily the same in terms of layout. */
7019 accumulate_vtbl_inits (tree binfo,
7027 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7029 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7031 /* If it doesn't have a vptr, we don't do anything. */
7032 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7035 /* If we're building a construction vtable, we're not interested in
7036 subobjects that don't require construction vtables. */
7038 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7039 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7042 /* Build the initializers for the BINFO-in-T vtable. */
7044 = chainon (TREE_VALUE (inits),
7045 dfs_accumulate_vtbl_inits (binfo, orig_binfo,
7046 rtti_binfo, t, inits));
7048 /* Walk the BINFO and its bases. We walk in preorder so that as we
7049 initialize each vtable we can figure out at what offset the
7050 secondary vtable lies from the primary vtable. We can't use
7051 dfs_walk here because we need to iterate through bases of BINFO
7052 and RTTI_BINFO simultaneously. */
7053 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7055 /* Skip virtual bases. */
7056 if (BINFO_VIRTUAL_P (base_binfo))
7058 accumulate_vtbl_inits (base_binfo,
7059 BINFO_BASE_BINFO (orig_binfo, i),
7065 /* Called from accumulate_vtbl_inits. Returns the initializers for
7066 the BINFO vtable. */
7069 dfs_accumulate_vtbl_inits (tree binfo,
7075 tree inits = NULL_TREE;
7076 tree vtbl = NULL_TREE;
7077 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7080 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7082 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7083 primary virtual base. If it is not the same primary in
7084 the hierarchy of T, we'll need to generate a ctor vtable
7085 for it, to place at its location in T. If it is the same
7086 primary, we still need a VTT entry for the vtable, but it
7087 should point to the ctor vtable for the base it is a
7088 primary for within the sub-hierarchy of RTTI_BINFO.
7090 There are three possible cases:
7092 1) We are in the same place.
7093 2) We are a primary base within a lost primary virtual base of
7095 3) We are primary to something not a base of RTTI_BINFO. */
7098 tree last = NULL_TREE;
7100 /* First, look through the bases we are primary to for RTTI_BINFO
7101 or a virtual base. */
7103 while (BINFO_PRIMARY_P (b))
7105 b = BINFO_INHERITANCE_CHAIN (b);
7107 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7110 /* If we run out of primary links, keep looking down our
7111 inheritance chain; we might be an indirect primary. */
7112 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7113 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7117 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7118 base B and it is a base of RTTI_BINFO, this is case 2. In
7119 either case, we share our vtable with LAST, i.e. the
7120 derived-most base within B of which we are a primary. */
7122 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7123 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7124 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7125 binfo_ctor_vtable after everything's been set up. */
7128 /* Otherwise, this is case 3 and we get our own. */
7130 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7138 /* Compute the initializer for this vtable. */
7139 inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7142 /* Figure out the position to which the VPTR should point. */
7143 vtbl = TREE_PURPOSE (l);
7144 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7145 index = size_binop (PLUS_EXPR,
7146 size_int (non_fn_entries),
7147 size_int (list_length (TREE_VALUE (l))));
7148 index = size_binop (MULT_EXPR,
7149 TYPE_SIZE_UNIT (vtable_entry_type),
7151 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7155 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7156 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7157 straighten this out. */
7158 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7159 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7162 /* For an ordinary vtable, set BINFO_VTABLE. */
7163 BINFO_VTABLE (binfo) = vtbl;
7168 static GTY(()) tree abort_fndecl_addr;
7170 /* Construct the initializer for BINFO's virtual function table. BINFO
7171 is part of the hierarchy dominated by T. If we're building a
7172 construction vtable, the ORIG_BINFO is the binfo we should use to
7173 find the actual function pointers to put in the vtable - but they
7174 can be overridden on the path to most-derived in the graph that
7175 ORIG_BINFO belongs. Otherwise,
7176 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7177 BINFO that should be indicated by the RTTI information in the
7178 vtable; it will be a base class of T, rather than T itself, if we
7179 are building a construction vtable.
7181 The value returned is a TREE_LIST suitable for wrapping in a
7182 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7183 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7184 number of non-function entries in the vtable.
7186 It might seem that this function should never be called with a
7187 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7188 base is always subsumed by a derived class vtable. However, when
7189 we are building construction vtables, we do build vtables for
7190 primary bases; we need these while the primary base is being
7194 build_vtbl_initializer (tree binfo,
7198 int* non_fn_entries_p)
7205 VEC(tree,gc) *vbases;
7207 /* Initialize VID. */
7208 memset (&vid, 0, sizeof (vid));
7211 vid.rtti_binfo = rtti_binfo;
7212 vid.last_init = &vid.inits;
7213 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7214 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7215 vid.generate_vcall_entries = true;
7216 /* The first vbase or vcall offset is at index -3 in the vtable. */
7217 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7219 /* Add entries to the vtable for RTTI. */
7220 build_rtti_vtbl_entries (binfo, &vid);
7222 /* Create an array for keeping track of the functions we've
7223 processed. When we see multiple functions with the same
7224 signature, we share the vcall offsets. */
7225 vid.fns = VEC_alloc (tree, gc, 32);
7226 /* Add the vcall and vbase offset entries. */
7227 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7229 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7230 build_vbase_offset_vtbl_entries. */
7231 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7232 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7233 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7235 /* If the target requires padding between data entries, add that now. */
7236 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7240 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7245 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7246 add = tree_cons (NULL_TREE,
7247 build1 (NOP_EXPR, vtable_entry_type,
7254 if (non_fn_entries_p)
7255 *non_fn_entries_p = list_length (vid.inits);
7257 /* Go through all the ordinary virtual functions, building up
7259 vfun_inits = NULL_TREE;
7260 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7264 tree fn, fn_original;
7265 tree init = NULL_TREE;
7269 if (DECL_THUNK_P (fn))
7271 if (!DECL_NAME (fn))
7273 if (THUNK_ALIAS (fn))
7275 fn = THUNK_ALIAS (fn);
7278 fn_original = THUNK_TARGET (fn);
7281 /* If the only definition of this function signature along our
7282 primary base chain is from a lost primary, this vtable slot will
7283 never be used, so just zero it out. This is important to avoid
7284 requiring extra thunks which cannot be generated with the function.
7286 We first check this in update_vtable_entry_for_fn, so we handle
7287 restored primary bases properly; we also need to do it here so we
7288 zero out unused slots in ctor vtables, rather than filling themff
7289 with erroneous values (though harmless, apart from relocation
7291 for (b = binfo; ; b = get_primary_binfo (b))
7293 /* We found a defn before a lost primary; go ahead as normal. */
7294 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7297 /* The nearest definition is from a lost primary; clear the
7299 if (BINFO_LOST_PRIMARY_P (b))
7301 init = size_zero_node;
7308 /* Pull the offset for `this', and the function to call, out of
7310 delta = BV_DELTA (v);
7311 vcall_index = BV_VCALL_INDEX (v);
7313 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7314 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7316 /* You can't call an abstract virtual function; it's abstract.
7317 So, we replace these functions with __pure_virtual. */
7318 if (DECL_PURE_VIRTUAL_P (fn_original))
7321 if (abort_fndecl_addr == NULL)
7322 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7323 init = abort_fndecl_addr;
7327 if (!integer_zerop (delta) || vcall_index)
7329 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7330 if (!DECL_NAME (fn))
7333 /* Take the address of the function, considering it to be of an
7334 appropriate generic type. */
7335 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7339 /* And add it to the chain of initializers. */
7340 if (TARGET_VTABLE_USES_DESCRIPTORS)
7343 if (init == size_zero_node)
7344 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7345 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7347 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7349 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7350 TREE_OPERAND (init, 0),
7351 build_int_cst (NULL_TREE, i));
7352 TREE_CONSTANT (fdesc) = 1;
7353 TREE_INVARIANT (fdesc) = 1;
7355 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7359 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7362 /* The initializers for virtual functions were built up in reverse
7363 order; straighten them out now. */
7364 vfun_inits = nreverse (vfun_inits);
7366 /* The negative offset initializers are also in reverse order. */
7367 vid.inits = nreverse (vid.inits);
7369 /* Chain the two together. */
7370 return chainon (vid.inits, vfun_inits);
7373 /* Adds to vid->inits the initializers for the vbase and vcall
7374 offsets in BINFO, which is in the hierarchy dominated by T. */
7377 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7381 /* If this is a derived class, we must first create entries
7382 corresponding to the primary base class. */
7383 b = get_primary_binfo (binfo);
7385 build_vcall_and_vbase_vtbl_entries (b, vid);
7387 /* Add the vbase entries for this base. */
7388 build_vbase_offset_vtbl_entries (binfo, vid);
7389 /* Add the vcall entries for this base. */
7390 build_vcall_offset_vtbl_entries (binfo, vid);
7393 /* Returns the initializers for the vbase offset entries in the vtable
7394 for BINFO (which is part of the class hierarchy dominated by T), in
7395 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7396 where the next vbase offset will go. */
7399 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7403 tree non_primary_binfo;
7405 /* If there are no virtual baseclasses, then there is nothing to
7407 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7412 /* We might be a primary base class. Go up the inheritance hierarchy
7413 until we find the most derived class of which we are a primary base:
7414 it is the offset of that which we need to use. */
7415 non_primary_binfo = binfo;
7416 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7420 /* If we have reached a virtual base, then it must be a primary
7421 base (possibly multi-level) of vid->binfo, or we wouldn't
7422 have called build_vcall_and_vbase_vtbl_entries for it. But it
7423 might be a lost primary, so just skip down to vid->binfo. */
7424 if (BINFO_VIRTUAL_P (non_primary_binfo))
7426 non_primary_binfo = vid->binfo;
7430 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7431 if (get_primary_binfo (b) != non_primary_binfo)
7433 non_primary_binfo = b;
7436 /* Go through the virtual bases, adding the offsets. */
7437 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7439 vbase = TREE_CHAIN (vbase))
7444 if (!BINFO_VIRTUAL_P (vbase))
7447 /* Find the instance of this virtual base in the complete
7449 b = copied_binfo (vbase, binfo);
7451 /* If we've already got an offset for this virtual base, we
7452 don't need another one. */
7453 if (BINFO_VTABLE_PATH_MARKED (b))
7455 BINFO_VTABLE_PATH_MARKED (b) = 1;
7457 /* Figure out where we can find this vbase offset. */
7458 delta = size_binop (MULT_EXPR,
7461 TYPE_SIZE_UNIT (vtable_entry_type)));
7462 if (vid->primary_vtbl_p)
7463 BINFO_VPTR_FIELD (b) = delta;
7465 if (binfo != TYPE_BINFO (t))
7466 /* The vbase offset had better be the same. */
7467 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7469 /* The next vbase will come at a more negative offset. */
7470 vid->index = size_binop (MINUS_EXPR, vid->index,
7471 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7473 /* The initializer is the delta from BINFO to this virtual base.
7474 The vbase offsets go in reverse inheritance-graph order, and
7475 we are walking in inheritance graph order so these end up in
7477 delta = size_diffop (BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7480 = build_tree_list (NULL_TREE,
7481 fold_build1 (NOP_EXPR,
7484 vid->last_init = &TREE_CHAIN (*vid->last_init);
7488 /* Adds the initializers for the vcall offset entries in the vtable
7489 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7493 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7495 /* We only need these entries if this base is a virtual base. We
7496 compute the indices -- but do not add to the vtable -- when
7497 building the main vtable for a class. */
7498 if (binfo == TYPE_BINFO (vid->derived)
7499 || (BINFO_VIRTUAL_P (binfo)
7500 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7501 correspond to VID->DERIVED), we are building a primary
7502 construction virtual table. Since this is a primary
7503 virtual table, we do not need the vcall offsets for
7505 && binfo != vid->rtti_binfo))
7507 /* We need a vcall offset for each of the virtual functions in this
7508 vtable. For example:
7510 class A { virtual void f (); };
7511 class B1 : virtual public A { virtual void f (); };
7512 class B2 : virtual public A { virtual void f (); };
7513 class C: public B1, public B2 { virtual void f (); };
7515 A C object has a primary base of B1, which has a primary base of A. A
7516 C also has a secondary base of B2, which no longer has a primary base
7517 of A. So the B2-in-C construction vtable needs a secondary vtable for
7518 A, which will adjust the A* to a B2* to call f. We have no way of
7519 knowing what (or even whether) this offset will be when we define B2,
7520 so we store this "vcall offset" in the A sub-vtable and look it up in
7521 a "virtual thunk" for B2::f.
7523 We need entries for all the functions in our primary vtable and
7524 in our non-virtual bases' secondary vtables. */
7526 /* If we are just computing the vcall indices -- but do not need
7527 the actual entries -- not that. */
7528 if (!BINFO_VIRTUAL_P (binfo))
7529 vid->generate_vcall_entries = false;
7530 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7531 add_vcall_offset_vtbl_entries_r (binfo, vid);
7535 /* Build vcall offsets, starting with those for BINFO. */
7538 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7544 /* Don't walk into virtual bases -- except, of course, for the
7545 virtual base for which we are building vcall offsets. Any
7546 primary virtual base will have already had its offsets generated
7547 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7548 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7551 /* If BINFO has a primary base, process it first. */
7552 primary_binfo = get_primary_binfo (binfo);
7554 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7556 /* Add BINFO itself to the list. */
7557 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7559 /* Scan the non-primary bases of BINFO. */
7560 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7561 if (base_binfo != primary_binfo)
7562 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7565 /* Called from build_vcall_offset_vtbl_entries_r. */
7568 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7570 /* Make entries for the rest of the virtuals. */
7571 if (abi_version_at_least (2))
7575 /* The ABI requires that the methods be processed in declaration
7576 order. G++ 3.2 used the order in the vtable. */
7577 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7579 orig_fn = TREE_CHAIN (orig_fn))
7580 if (DECL_VINDEX (orig_fn))
7581 add_vcall_offset (orig_fn, binfo, vid);
7585 tree derived_virtuals;
7588 /* If BINFO is a primary base, the most derived class which has
7589 BINFO as a primary base; otherwise, just BINFO. */
7590 tree non_primary_binfo;
7592 /* We might be a primary base class. Go up the inheritance hierarchy
7593 until we find the most derived class of which we are a primary base:
7594 it is the BINFO_VIRTUALS there that we need to consider. */
7595 non_primary_binfo = binfo;
7596 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7600 /* If we have reached a virtual base, then it must be vid->vbase,
7601 because we ignore other virtual bases in
7602 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7603 base (possibly multi-level) of vid->binfo, or we wouldn't
7604 have called build_vcall_and_vbase_vtbl_entries for it. But it
7605 might be a lost primary, so just skip down to vid->binfo. */
7606 if (BINFO_VIRTUAL_P (non_primary_binfo))
7608 gcc_assert (non_primary_binfo == vid->vbase);
7609 non_primary_binfo = vid->binfo;
7613 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7614 if (get_primary_binfo (b) != non_primary_binfo)
7616 non_primary_binfo = b;
7619 if (vid->ctor_vtbl_p)
7620 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7621 where rtti_binfo is the most derived type. */
7623 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7625 for (base_virtuals = BINFO_VIRTUALS (binfo),
7626 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7627 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7629 base_virtuals = TREE_CHAIN (base_virtuals),
7630 derived_virtuals = TREE_CHAIN (derived_virtuals),
7631 orig_virtuals = TREE_CHAIN (orig_virtuals))
7635 /* Find the declaration that originally caused this function to
7636 be present in BINFO_TYPE (binfo). */
7637 orig_fn = BV_FN (orig_virtuals);
7639 /* When processing BINFO, we only want to generate vcall slots for
7640 function slots introduced in BINFO. So don't try to generate
7641 one if the function isn't even defined in BINFO. */
7642 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7645 add_vcall_offset (orig_fn, binfo, vid);
7650 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7653 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7659 /* If there is already an entry for a function with the same
7660 signature as FN, then we do not need a second vcall offset.
7661 Check the list of functions already present in the derived
7663 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7665 if (same_signature_p (derived_entry, orig_fn)
7666 /* We only use one vcall offset for virtual destructors,
7667 even though there are two virtual table entries. */
7668 || (DECL_DESTRUCTOR_P (derived_entry)
7669 && DECL_DESTRUCTOR_P (orig_fn)))
7673 /* If we are building these vcall offsets as part of building
7674 the vtable for the most derived class, remember the vcall
7676 if (vid->binfo == TYPE_BINFO (vid->derived))
7678 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
7679 CLASSTYPE_VCALL_INDICES (vid->derived),
7681 elt->purpose = orig_fn;
7682 elt->value = vid->index;
7685 /* The next vcall offset will be found at a more negative
7687 vid->index = size_binop (MINUS_EXPR, vid->index,
7688 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7690 /* Keep track of this function. */
7691 VEC_safe_push (tree, gc, vid->fns, orig_fn);
7693 if (vid->generate_vcall_entries)
7698 /* Find the overriding function. */
7699 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
7700 if (fn == error_mark_node)
7701 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
7705 base = TREE_VALUE (fn);
7707 /* The vbase we're working on is a primary base of
7708 vid->binfo. But it might be a lost primary, so its
7709 BINFO_OFFSET might be wrong, so we just use the
7710 BINFO_OFFSET from vid->binfo. */
7711 vcall_offset = size_diffop (BINFO_OFFSET (base),
7712 BINFO_OFFSET (vid->binfo));
7713 vcall_offset = fold_build1 (NOP_EXPR, vtable_entry_type,
7716 /* Add the initializer to the vtable. */
7717 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
7718 vid->last_init = &TREE_CHAIN (*vid->last_init);
7722 /* Return vtbl initializers for the RTTI entries corresponding to the
7723 BINFO's vtable. The RTTI entries should indicate the object given
7724 by VID->rtti_binfo. */
7727 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
7736 basetype = BINFO_TYPE (binfo);
7737 t = BINFO_TYPE (vid->rtti_binfo);
7739 /* To find the complete object, we will first convert to our most
7740 primary base, and then add the offset in the vtbl to that value. */
7742 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
7743 && !BINFO_LOST_PRIMARY_P (b))
7747 primary_base = get_primary_binfo (b);
7748 gcc_assert (BINFO_PRIMARY_P (primary_base)
7749 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
7752 offset = size_diffop (BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
7754 /* The second entry is the address of the typeinfo object. */
7756 decl = build_address (get_tinfo_decl (t));
7758 decl = integer_zero_node;
7760 /* Convert the declaration to a type that can be stored in the
7762 init = build_nop (vfunc_ptr_type_node, decl);
7763 *vid->last_init = build_tree_list (NULL_TREE, init);
7764 vid->last_init = &TREE_CHAIN (*vid->last_init);
7766 /* Add the offset-to-top entry. It comes earlier in the vtable than
7767 the typeinfo entry. Convert the offset to look like a
7768 function pointer, so that we can put it in the vtable. */
7769 init = build_nop (vfunc_ptr_type_node, offset);
7770 *vid->last_init = build_tree_list (NULL_TREE, init);
7771 vid->last_init = &TREE_CHAIN (*vid->last_init);
7774 /* Fold a OBJ_TYPE_REF expression to the address of a function.
7775 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
7778 cp_fold_obj_type_ref (tree ref, tree known_type)
7780 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
7781 HOST_WIDE_INT i = 0;
7782 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
7787 i += (TARGET_VTABLE_USES_DESCRIPTORS
7788 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
7794 #ifdef ENABLE_CHECKING
7795 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
7796 DECL_VINDEX (fndecl)));
7799 cgraph_node (fndecl)->local.vtable_method = true;
7801 return build_address (fndecl);
7804 #include "gt-cp-class.h"