1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
39 #include "tree-dump.h"
41 /* The number of nested classes being processed. If we are not in the
42 scope of any class, this is zero. */
44 int current_class_depth;
46 /* In order to deal with nested classes, we keep a stack of classes.
47 The topmost entry is the innermost class, and is the entry at index
48 CURRENT_CLASS_DEPTH */
50 typedef struct class_stack_node {
51 /* The name of the class. */
54 /* The _TYPE node for the class. */
57 /* The access specifier pending for new declarations in the scope of
61 /* If were defining TYPE, the names used in this class. */
62 splay_tree names_used;
64 /* Nonzero if this class is no longer open, because of a call to
67 }* class_stack_node_t;
69 typedef struct vtbl_init_data_s
71 /* The base for which we're building initializers. */
73 /* The type of the most-derived type. */
75 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
76 unless ctor_vtbl_p is true. */
78 /* The negative-index vtable initializers built up so far. These
79 are in order from least negative index to most negative index. */
81 /* The last (i.e., most negative) entry in INITS. */
83 /* The binfo for the virtual base for which we're building
84 vcall offset initializers. */
86 /* The functions in vbase for which we have already provided vcall
89 /* The vtable index of the next vcall or vbase offset. */
91 /* Nonzero if we are building the initializer for the primary
94 /* Nonzero if we are building the initializer for a construction
97 /* True when adding vcall offset entries to the vtable. False when
98 merely computing the indices. */
99 bool generate_vcall_entries;
102 /* The type of a function passed to walk_subobject_offsets. */
103 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
105 /* The stack itself. This is a dynamically resized array. The
106 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
107 static int current_class_stack_size;
108 static class_stack_node_t current_class_stack;
110 /* The size of the largest empty class seen in this translation unit. */
111 static GTY (()) tree sizeof_biggest_empty_class;
113 /* An array of all local classes present in this translation unit, in
114 declaration order. */
115 VEC(tree,gc) *local_classes;
117 static tree get_vfield_name (tree);
118 static void finish_struct_anon (tree);
119 static tree get_vtable_name (tree);
120 static tree get_basefndecls (tree, tree);
121 static int build_primary_vtable (tree, tree);
122 static int build_secondary_vtable (tree);
123 static void finish_vtbls (tree);
124 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
125 static void finish_struct_bits (tree);
126 static int alter_access (tree, tree, tree);
127 static void handle_using_decl (tree, tree);
128 static tree dfs_modify_vtables (tree, void *);
129 static tree modify_all_vtables (tree, tree);
130 static void determine_primary_bases (tree);
131 static void finish_struct_methods (tree);
132 static void maybe_warn_about_overly_private_class (tree);
133 static int method_name_cmp (const void *, const void *);
134 static int resort_method_name_cmp (const void *, const void *);
135 static void add_implicitly_declared_members (tree, int, int);
136 static tree fixed_type_or_null (tree, int *, int *);
137 static tree build_simple_base_path (tree expr, tree binfo);
138 static tree build_vtbl_ref_1 (tree, tree);
139 static tree build_vtbl_initializer (tree, tree, tree, tree, int *);
140 static int count_fields (tree);
141 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
142 static bool check_bitfield_decl (tree);
143 static void check_field_decl (tree, tree, int *, int *, int *);
144 static void check_field_decls (tree, tree *, int *, int *);
145 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
146 static void build_base_fields (record_layout_info, splay_tree, tree *);
147 static void check_methods (tree);
148 static void remove_zero_width_bit_fields (tree);
149 static void check_bases (tree, int *, int *);
150 static void check_bases_and_members (tree);
151 static tree create_vtable_ptr (tree, tree *);
152 static void include_empty_classes (record_layout_info);
153 static void layout_class_type (tree, tree *);
154 static void fixup_pending_inline (tree);
155 static void fixup_inline_methods (tree);
156 static void propagate_binfo_offsets (tree, tree);
157 static void layout_virtual_bases (record_layout_info, splay_tree);
158 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
159 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
160 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
161 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
162 static void add_vcall_offset (tree, tree, vtbl_init_data *);
163 static void layout_vtable_decl (tree, int);
164 static tree dfs_find_final_overrider_pre (tree, void *);
165 static tree dfs_find_final_overrider_post (tree, void *);
166 static tree find_final_overrider (tree, tree, tree);
167 static int make_new_vtable (tree, tree);
168 static tree get_primary_binfo (tree);
169 static int maybe_indent_hierarchy (FILE *, int, int);
170 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
171 static void dump_class_hierarchy (tree);
172 static void dump_class_hierarchy_1 (FILE *, int, tree);
173 static void dump_array (FILE *, tree);
174 static void dump_vtable (tree, tree, tree);
175 static void dump_vtt (tree, tree);
176 static void dump_thunk (FILE *, int, tree);
177 static tree build_vtable (tree, tree, tree);
178 static void initialize_vtable (tree, tree);
179 static void layout_nonempty_base_or_field (record_layout_info,
180 tree, tree, splay_tree);
181 static tree end_of_class (tree, int);
182 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
183 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree);
184 static tree dfs_accumulate_vtbl_inits (tree, tree, tree, tree,
186 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
187 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
188 static void clone_constructors_and_destructors (tree);
189 static tree build_clone (tree, tree);
190 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
191 static void build_ctor_vtbl_group (tree, tree);
192 static void build_vtt (tree);
193 static tree binfo_ctor_vtable (tree);
194 static tree *build_vtt_inits (tree, tree, tree *, tree *);
195 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
196 static tree dfs_fixup_binfo_vtbls (tree, void *);
197 static int record_subobject_offset (tree, tree, splay_tree);
198 static int check_subobject_offset (tree, tree, splay_tree);
199 static int walk_subobject_offsets (tree, subobject_offset_fn,
200 tree, splay_tree, tree, int);
201 static void record_subobject_offsets (tree, tree, splay_tree, bool);
202 static int layout_conflict_p (tree, tree, splay_tree, int);
203 static int splay_tree_compare_integer_csts (splay_tree_key k1,
205 static void warn_about_ambiguous_bases (tree);
206 static bool type_requires_array_cookie (tree);
207 static bool contains_empty_class_p (tree);
208 static bool base_derived_from (tree, tree);
209 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
210 static tree end_of_base (tree);
211 static tree get_vcall_index (tree, tree);
213 /* Variables shared between class.c and call.c. */
215 #ifdef GATHER_STATISTICS
217 int n_vtable_entries = 0;
218 int n_vtable_searches = 0;
219 int n_vtable_elems = 0;
220 int n_convert_harshness = 0;
221 int n_compute_conversion_costs = 0;
222 int n_inner_fields_searched = 0;
225 /* Convert to or from a base subobject. EXPR is an expression of type
226 `A' or `A*', an expression of type `B' or `B*' is returned. To
227 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
228 the B base instance within A. To convert base A to derived B, CODE
229 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
230 In this latter case, A must not be a morally virtual base of B.
231 NONNULL is true if EXPR is known to be non-NULL (this is only
232 needed when EXPR is of pointer type). CV qualifiers are preserved
236 build_base_path (enum tree_code code,
241 tree v_binfo = NULL_TREE;
242 tree d_binfo = NULL_TREE;
246 tree null_test = NULL;
247 tree ptr_target_type;
249 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
250 bool has_empty = false;
253 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
254 return error_mark_node;
256 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
259 if (is_empty_class (BINFO_TYPE (probe)))
261 if (!v_binfo && BINFO_VIRTUAL_P (probe))
265 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
267 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
269 gcc_assert ((code == MINUS_EXPR
270 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
271 || (code == PLUS_EXPR
272 && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
274 if (binfo == d_binfo)
278 if (code == MINUS_EXPR && v_binfo)
280 error ("cannot convert from base %qT to derived type %qT via virtual base %qT",
281 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
282 return error_mark_node;
286 /* This must happen before the call to save_expr. */
287 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
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 /* Don't bother with the calculations inside sizeof; they'll ICE if the
297 source type is incomplete and the pointer value doesn't matter. */
300 expr = build_nop (build_pointer_type (target_type), expr);
302 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, NULL);
306 /* Do we need to check for a null pointer? */
307 if (want_pointer && !nonnull)
309 /* If we know the conversion will not actually change the value
310 of EXPR, then we can avoid testing the expression for NULL.
311 We have to avoid generating a COMPONENT_REF for a base class
312 field, because other parts of the compiler know that such
313 expressions are always non-NULL. */
314 if (!virtual_access && integer_zerop (offset))
317 /* TARGET_TYPE has been extracted from BINFO, and, is
318 therefore always cv-unqualified. Extract the
319 cv-qualifiers from EXPR so that the expression returned
320 matches the input. */
321 class_type = TREE_TYPE (TREE_TYPE (expr));
323 = cp_build_qualified_type (target_type,
324 cp_type_quals (class_type));
325 return build_nop (build_pointer_type (target_type), expr);
327 null_test = error_mark_node;
330 /* Protect against multiple evaluation if necessary. */
331 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
332 expr = save_expr (expr);
334 /* Now that we've saved expr, build the real null test. */
337 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
338 null_test = fold_build2 (NE_EXPR, boolean_type_node,
342 /* If this is a simple base reference, express it as a COMPONENT_REF. */
343 if (code == PLUS_EXPR && !virtual_access
344 /* We don't build base fields for empty bases, and they aren't very
345 interesting to the optimizers anyway. */
348 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
349 expr = build_simple_base_path (expr, binfo);
351 expr = build_address (expr);
352 target_type = TREE_TYPE (expr);
358 /* Going via virtual base V_BINFO. We need the static offset
359 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
360 V_BINFO. That offset is an entry in D_BINFO's vtable. */
363 if (fixed_type_p < 0 && in_base_initializer)
365 /* In a base member initializer, we cannot rely on the
366 vtable being set up. We have to indirect via the
370 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
371 t = build_pointer_type (t);
372 v_offset = convert (t, current_vtt_parm);
373 v_offset = cp_build_indirect_ref (v_offset, NULL,
374 tf_warning_or_error);
377 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, NULL,
378 tf_warning_or_error),
379 TREE_TYPE (TREE_TYPE (expr)));
381 v_offset = build2 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
382 v_offset, fold_convert (sizetype, BINFO_VPTR_FIELD (v_binfo)));
383 v_offset = build1 (NOP_EXPR,
384 build_pointer_type (ptrdiff_type_node),
386 v_offset = cp_build_indirect_ref (v_offset, NULL, tf_warning_or_error);
387 TREE_CONSTANT (v_offset) = 1;
389 offset = convert_to_integer (ptrdiff_type_node,
391 BINFO_OFFSET (v_binfo)));
393 if (!integer_zerop (offset))
394 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
396 if (fixed_type_p < 0)
397 /* Negative fixed_type_p means this is a constructor or destructor;
398 virtual base layout is fixed in in-charge [cd]tors, but not in
400 offset = build3 (COND_EXPR, ptrdiff_type_node,
401 build2 (EQ_EXPR, boolean_type_node,
402 current_in_charge_parm, integer_zero_node),
404 convert_to_integer (ptrdiff_type_node,
405 BINFO_OFFSET (binfo)));
410 target_type = cp_build_qualified_type
411 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
412 ptr_target_type = build_pointer_type (target_type);
414 target_type = ptr_target_type;
416 expr = build1 (NOP_EXPR, ptr_target_type, expr);
418 if (!integer_zerop (offset))
420 offset = fold_convert (sizetype, offset);
421 if (code == MINUS_EXPR)
422 offset = fold_build1 (NEGATE_EXPR, sizetype, offset);
423 expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
429 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
433 expr = fold_build3 (COND_EXPR, target_type, null_test, expr,
434 fold_build1 (NOP_EXPR, target_type,
440 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
441 Perform a derived-to-base conversion by recursively building up a
442 sequence of COMPONENT_REFs to the appropriate base fields. */
445 build_simple_base_path (tree expr, tree binfo)
447 tree type = BINFO_TYPE (binfo);
448 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
451 if (d_binfo == NULL_TREE)
455 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
457 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
458 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
459 an lvalue in the front end; only _DECLs and _REFs are lvalues
461 temp = unary_complex_lvalue (ADDR_EXPR, expr);
463 expr = cp_build_indirect_ref (temp, NULL, tf_warning_or_error);
469 expr = build_simple_base_path (expr, d_binfo);
471 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
472 field; field = TREE_CHAIN (field))
473 /* Is this the base field created by build_base_field? */
474 if (TREE_CODE (field) == FIELD_DECL
475 && DECL_FIELD_IS_BASE (field)
476 && TREE_TYPE (field) == type)
478 /* We don't use build_class_member_access_expr here, as that
479 has unnecessary checks, and more importantly results in
480 recursive calls to dfs_walk_once. */
481 int type_quals = cp_type_quals (TREE_TYPE (expr));
483 expr = build3 (COMPONENT_REF,
484 cp_build_qualified_type (type, type_quals),
485 expr, field, NULL_TREE);
486 expr = fold_if_not_in_template (expr);
488 /* Mark the expression const or volatile, as appropriate.
489 Even though we've dealt with the type above, we still have
490 to mark the expression itself. */
491 if (type_quals & TYPE_QUAL_CONST)
492 TREE_READONLY (expr) = 1;
493 if (type_quals & TYPE_QUAL_VOLATILE)
494 TREE_THIS_VOLATILE (expr) = 1;
499 /* Didn't find the base field?!? */
503 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
504 type is a class type or a pointer to a class type. In the former
505 case, TYPE is also a class type; in the latter it is another
506 pointer type. If CHECK_ACCESS is true, an error message is emitted
507 if TYPE is inaccessible. If OBJECT has pointer type, the value is
508 assumed to be non-NULL. */
511 convert_to_base (tree object, tree type, bool check_access, bool nonnull)
516 if (TYPE_PTR_P (TREE_TYPE (object)))
518 object_type = TREE_TYPE (TREE_TYPE (object));
519 type = TREE_TYPE (type);
522 object_type = TREE_TYPE (object);
524 binfo = lookup_base (object_type, type,
525 check_access ? ba_check : ba_unique,
527 if (!binfo || binfo == error_mark_node)
528 return error_mark_node;
530 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
533 /* EXPR is an expression with unqualified class type. BASE is a base
534 binfo of that class type. Returns EXPR, converted to the BASE
535 type. This function assumes that EXPR is the most derived class;
536 therefore virtual bases can be found at their static offsets. */
539 convert_to_base_statically (tree expr, tree base)
543 expr_type = TREE_TYPE (expr);
544 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
548 pointer_type = build_pointer_type (expr_type);
550 /* We use fold_build2 and fold_convert below to simplify the trees
551 provided to the optimizers. It is not safe to call these functions
552 when processing a template because they do not handle C++-specific
554 gcc_assert (!processing_template_decl);
555 expr = cp_build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1,
556 tf_warning_or_error);
557 if (!integer_zerop (BINFO_OFFSET (base)))
558 expr = fold_build2 (POINTER_PLUS_EXPR, pointer_type, expr,
559 fold_convert (sizetype, BINFO_OFFSET (base)));
560 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
561 expr = build_fold_indirect_ref (expr);
569 build_vfield_ref (tree datum, tree type)
571 tree vfield, vcontext;
573 if (datum == error_mark_node)
574 return error_mark_node;
576 /* First, convert to the requested type. */
577 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
578 datum = convert_to_base (datum, type, /*check_access=*/false,
581 /* Second, the requested type may not be the owner of its own vptr.
582 If not, convert to the base class that owns it. We cannot use
583 convert_to_base here, because VCONTEXT may appear more than once
584 in the inheritance hierarchy of TYPE, and thus direct conversion
585 between the types may be ambiguous. Following the path back up
586 one step at a time via primary bases avoids the problem. */
587 vfield = TYPE_VFIELD (type);
588 vcontext = DECL_CONTEXT (vfield);
589 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
591 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
592 type = TREE_TYPE (datum);
595 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
598 /* Given an object INSTANCE, return an expression which yields the
599 vtable element corresponding to INDEX. There are many special
600 cases for INSTANCE which we take care of here, mainly to avoid
601 creating extra tree nodes when we don't have to. */
604 build_vtbl_ref_1 (tree instance, tree idx)
607 tree vtbl = NULL_TREE;
609 /* Try to figure out what a reference refers to, and
610 access its virtual function table directly. */
613 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
615 tree basetype = non_reference (TREE_TYPE (instance));
617 if (fixed_type && !cdtorp)
619 tree binfo = lookup_base (fixed_type, basetype,
620 ba_unique | ba_quiet, NULL);
622 vtbl = unshare_expr (BINFO_VTABLE (binfo));
626 vtbl = build_vfield_ref (instance, basetype);
628 assemble_external (vtbl);
630 aref = build_array_ref (vtbl, idx, input_location);
631 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
637 build_vtbl_ref (tree instance, tree idx)
639 tree aref = build_vtbl_ref_1 (instance, idx);
644 /* Given a stable object pointer INSTANCE_PTR, return an expression which
645 yields a function pointer corresponding to vtable element INDEX. */
648 build_vfn_ref (tree instance_ptr, tree idx)
652 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, 0,
653 tf_warning_or_error),
656 /* When using function descriptors, the address of the
657 vtable entry is treated as a function pointer. */
658 if (TARGET_VTABLE_USES_DESCRIPTORS)
659 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
660 cp_build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1,
661 tf_warning_or_error));
663 /* Remember this as a method reference, for later devirtualization. */
664 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
669 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
670 for the given TYPE. */
673 get_vtable_name (tree type)
675 return mangle_vtbl_for_type (type);
678 /* DECL is an entity associated with TYPE, like a virtual table or an
679 implicitly generated constructor. Determine whether or not DECL
680 should have external or internal linkage at the object file
681 level. This routine does not deal with COMDAT linkage and other
682 similar complexities; it simply sets TREE_PUBLIC if it possible for
683 entities in other translation units to contain copies of DECL, in
687 set_linkage_according_to_type (tree type, tree decl)
689 /* If TYPE involves a local class in a function with internal
690 linkage, then DECL should have internal linkage too. Other local
691 classes have no linkage -- but if their containing functions
692 have external linkage, it makes sense for DECL to have external
693 linkage too. That will allow template definitions to be merged,
695 if (no_linkage_check (type, /*relaxed_p=*/true))
697 TREE_PUBLIC (decl) = 0;
698 DECL_INTERFACE_KNOWN (decl) = 1;
701 TREE_PUBLIC (decl) = 1;
704 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
705 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
706 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
709 build_vtable (tree class_type, tree name, tree vtable_type)
713 decl = build_lang_decl (VAR_DECL, name, vtable_type);
714 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
715 now to avoid confusion in mangle_decl. */
716 SET_DECL_ASSEMBLER_NAME (decl, name);
717 DECL_CONTEXT (decl) = class_type;
718 DECL_ARTIFICIAL (decl) = 1;
719 TREE_STATIC (decl) = 1;
720 TREE_READONLY (decl) = 1;
721 DECL_VIRTUAL_P (decl) = 1;
722 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
723 DECL_VTABLE_OR_VTT_P (decl) = 1;
724 /* At one time the vtable info was grabbed 2 words at a time. This
725 fails on sparc unless you have 8-byte alignment. (tiemann) */
726 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
728 set_linkage_according_to_type (class_type, decl);
729 /* The vtable has not been defined -- yet. */
730 DECL_EXTERNAL (decl) = 1;
731 DECL_NOT_REALLY_EXTERN (decl) = 1;
733 /* Mark the VAR_DECL node representing the vtable itself as a
734 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
735 is rather important that such things be ignored because any
736 effort to actually generate DWARF for them will run into
737 trouble when/if we encounter code like:
740 struct S { virtual void member (); };
742 because the artificial declaration of the vtable itself (as
743 manufactured by the g++ front end) will say that the vtable is
744 a static member of `S' but only *after* the debug output for
745 the definition of `S' has already been output. This causes
746 grief because the DWARF entry for the definition of the vtable
747 will try to refer back to an earlier *declaration* of the
748 vtable as a static member of `S' and there won't be one. We
749 might be able to arrange to have the "vtable static member"
750 attached to the member list for `S' before the debug info for
751 `S' get written (which would solve the problem) but that would
752 require more intrusive changes to the g++ front end. */
753 DECL_IGNORED_P (decl) = 1;
758 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
759 or even complete. If this does not exist, create it. If COMPLETE is
760 nonzero, then complete the definition of it -- that will render it
761 impossible to actually build the vtable, but is useful to get at those
762 which are known to exist in the runtime. */
765 get_vtable_decl (tree type, int complete)
769 if (CLASSTYPE_VTABLES (type))
770 return CLASSTYPE_VTABLES (type);
772 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
773 CLASSTYPE_VTABLES (type) = decl;
777 DECL_EXTERNAL (decl) = 1;
778 finish_decl (decl, NULL_TREE, NULL_TREE);
784 /* Build the primary virtual function table for TYPE. If BINFO is
785 non-NULL, build the vtable starting with the initial approximation
786 that it is the same as the one which is the head of the association
787 list. Returns a nonzero value if a new vtable is actually
791 build_primary_vtable (tree binfo, tree type)
796 decl = get_vtable_decl (type, /*complete=*/0);
800 if (BINFO_NEW_VTABLE_MARKED (binfo))
801 /* We have already created a vtable for this base, so there's
802 no need to do it again. */
805 virtuals = copy_list (BINFO_VIRTUALS (binfo));
806 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
807 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
808 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
812 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
813 virtuals = NULL_TREE;
816 #ifdef GATHER_STATISTICS
818 n_vtable_elems += list_length (virtuals);
821 /* Initialize the association list for this type, based
822 on our first approximation. */
823 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
824 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
825 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
829 /* Give BINFO a new virtual function table which is initialized
830 with a skeleton-copy of its original initialization. The only
831 entry that changes is the `delta' entry, so we can really
832 share a lot of structure.
834 FOR_TYPE is the most derived type which caused this table to
837 Returns nonzero if we haven't met BINFO before.
839 The order in which vtables are built (by calling this function) for
840 an object must remain the same, otherwise a binary incompatibility
844 build_secondary_vtable (tree binfo)
846 if (BINFO_NEW_VTABLE_MARKED (binfo))
847 /* We already created a vtable for this base. There's no need to
851 /* Remember that we've created a vtable for this BINFO, so that we
852 don't try to do so again. */
853 SET_BINFO_NEW_VTABLE_MARKED (binfo);
855 /* Make fresh virtual list, so we can smash it later. */
856 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
858 /* Secondary vtables are laid out as part of the same structure as
859 the primary vtable. */
860 BINFO_VTABLE (binfo) = NULL_TREE;
864 /* Create a new vtable for BINFO which is the hierarchy dominated by
865 T. Return nonzero if we actually created a new vtable. */
868 make_new_vtable (tree t, tree binfo)
870 if (binfo == TYPE_BINFO (t))
871 /* In this case, it is *type*'s vtable we are modifying. We start
872 with the approximation that its vtable is that of the
873 immediate base class. */
874 return build_primary_vtable (binfo, t);
876 /* This is our very own copy of `basetype' to play with. Later,
877 we will fill in all the virtual functions that override the
878 virtual functions in these base classes which are not defined
879 by the current type. */
880 return build_secondary_vtable (binfo);
883 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
884 (which is in the hierarchy dominated by T) list FNDECL as its
885 BV_FN. DELTA is the required constant adjustment from the `this'
886 pointer where the vtable entry appears to the `this' required when
887 the function is actually called. */
890 modify_vtable_entry (tree t,
900 if (fndecl != BV_FN (v)
901 || !tree_int_cst_equal (delta, BV_DELTA (v)))
903 /* We need a new vtable for BINFO. */
904 if (make_new_vtable (t, binfo))
906 /* If we really did make a new vtable, we also made a copy
907 of the BINFO_VIRTUALS list. Now, we have to find the
908 corresponding entry in that list. */
909 *virtuals = BINFO_VIRTUALS (binfo);
910 while (BV_FN (*virtuals) != BV_FN (v))
911 *virtuals = TREE_CHAIN (*virtuals);
915 BV_DELTA (v) = delta;
916 BV_VCALL_INDEX (v) = NULL_TREE;
922 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
923 the USING_DECL naming METHOD. Returns true if the method could be
924 added to the method vec. */
927 add_method (tree type, tree method, tree using_decl)
931 bool template_conv_p = false;
933 VEC(tree,gc) *method_vec;
935 bool insert_p = false;
939 if (method == error_mark_node)
942 complete_p = COMPLETE_TYPE_P (type);
943 conv_p = DECL_CONV_FN_P (method);
945 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
946 && DECL_TEMPLATE_CONV_FN_P (method));
948 method_vec = CLASSTYPE_METHOD_VEC (type);
951 /* Make a new method vector. We start with 8 entries. We must
952 allocate at least two (for constructors and destructors), and
953 we're going to end up with an assignment operator at some
955 method_vec = VEC_alloc (tree, gc, 8);
956 /* Create slots for constructors and destructors. */
957 VEC_quick_push (tree, method_vec, NULL_TREE);
958 VEC_quick_push (tree, method_vec, NULL_TREE);
959 CLASSTYPE_METHOD_VEC (type) = method_vec;
962 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
963 grok_special_member_properties (method);
965 /* Constructors and destructors go in special slots. */
966 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
967 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
968 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
970 slot = CLASSTYPE_DESTRUCTOR_SLOT;
972 if (TYPE_FOR_JAVA (type))
974 if (!DECL_ARTIFICIAL (method))
975 error ("Java class %qT cannot have a destructor", type);
976 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
977 error ("Java class %qT cannot have an implicit non-trivial "
987 /* See if we already have an entry with this name. */
988 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
989 VEC_iterate (tree, method_vec, slot, m);
995 if (TREE_CODE (m) == TEMPLATE_DECL
996 && DECL_TEMPLATE_CONV_FN_P (m))
1000 if (conv_p && !DECL_CONV_FN_P (m))
1002 if (DECL_NAME (m) == DECL_NAME (method))
1008 && !DECL_CONV_FN_P (m)
1009 && DECL_NAME (m) > DECL_NAME (method))
1013 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1015 /* Check to see if we've already got this method. */
1016 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1018 tree fn = OVL_CURRENT (fns);
1024 if (TREE_CODE (fn) != TREE_CODE (method))
1027 /* [over.load] Member function declarations with the
1028 same name and the same parameter types cannot be
1029 overloaded if any of them is a static member
1030 function declaration.
1032 [namespace.udecl] When a using-declaration brings names
1033 from a base class into a derived class scope, member
1034 functions in the derived class override and/or hide member
1035 functions with the same name and parameter types in a base
1036 class (rather than conflicting). */
1037 fn_type = TREE_TYPE (fn);
1038 method_type = TREE_TYPE (method);
1039 parms1 = TYPE_ARG_TYPES (fn_type);
1040 parms2 = TYPE_ARG_TYPES (method_type);
1042 /* Compare the quals on the 'this' parm. Don't compare
1043 the whole types, as used functions are treated as
1044 coming from the using class in overload resolution. */
1045 if (! DECL_STATIC_FUNCTION_P (fn)
1046 && ! DECL_STATIC_FUNCTION_P (method)
1047 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1048 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1049 && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
1050 != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
1053 /* For templates, the return type and template parameters
1054 must be identical. */
1055 if (TREE_CODE (fn) == TEMPLATE_DECL
1056 && (!same_type_p (TREE_TYPE (fn_type),
1057 TREE_TYPE (method_type))
1058 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1059 DECL_TEMPLATE_PARMS (method))))
1062 if (! DECL_STATIC_FUNCTION_P (fn))
1063 parms1 = TREE_CHAIN (parms1);
1064 if (! DECL_STATIC_FUNCTION_P (method))
1065 parms2 = TREE_CHAIN (parms2);
1067 if (compparms (parms1, parms2)
1068 && (!DECL_CONV_FN_P (fn)
1069 || same_type_p (TREE_TYPE (fn_type),
1070 TREE_TYPE (method_type))))
1074 if (DECL_CONTEXT (fn) == type)
1075 /* Defer to the local function. */
1077 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1078 error ("repeated using declaration %q+D", using_decl);
1080 error ("using declaration %q+D conflicts with a previous using declaration",
1085 error ("%q+#D cannot be overloaded", method);
1086 error ("with %q+#D", fn);
1089 /* We don't call duplicate_decls here to merge the
1090 declarations because that will confuse things if the
1091 methods have inline definitions. In particular, we
1092 will crash while processing the definitions. */
1097 /* A class should never have more than one destructor. */
1098 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1101 /* Add the new binding. */
1102 overload = build_overload (method, current_fns);
1105 TYPE_HAS_CONVERSION (type) = 1;
1106 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1107 push_class_level_binding (DECL_NAME (method), overload);
1113 /* We only expect to add few methods in the COMPLETE_P case, so
1114 just make room for one more method in that case. */
1116 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1118 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1120 CLASSTYPE_METHOD_VEC (type) = method_vec;
1121 if (slot == VEC_length (tree, method_vec))
1122 VEC_quick_push (tree, method_vec, overload);
1124 VEC_quick_insert (tree, method_vec, slot, overload);
1127 /* Replace the current slot. */
1128 VEC_replace (tree, method_vec, slot, overload);
1132 /* Subroutines of finish_struct. */
1134 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1135 legit, otherwise return 0. */
1138 alter_access (tree t, tree fdecl, tree access)
1142 if (!DECL_LANG_SPECIFIC (fdecl))
1143 retrofit_lang_decl (fdecl);
1145 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1147 elem = purpose_member (t, DECL_ACCESS (fdecl));
1150 if (TREE_VALUE (elem) != access)
1152 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1153 error ("conflicting access specifications for method"
1154 " %q+D, ignored", TREE_TYPE (fdecl));
1156 error ("conflicting access specifications for field %qE, ignored",
1161 /* They're changing the access to the same thing they changed
1162 it to before. That's OK. */
1168 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1169 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1175 /* Process the USING_DECL, which is a member of T. */
1178 handle_using_decl (tree using_decl, tree t)
1180 tree decl = USING_DECL_DECLS (using_decl);
1181 tree name = DECL_NAME (using_decl);
1183 = TREE_PRIVATE (using_decl) ? access_private_node
1184 : TREE_PROTECTED (using_decl) ? access_protected_node
1185 : access_public_node;
1186 tree flist = NULL_TREE;
1189 gcc_assert (!processing_template_decl && decl);
1191 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1194 if (is_overloaded_fn (old_value))
1195 old_value = OVL_CURRENT (old_value);
1197 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1200 old_value = NULL_TREE;
1203 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1205 if (is_overloaded_fn (decl))
1210 else if (is_overloaded_fn (old_value))
1213 /* It's OK to use functions from a base when there are functions with
1214 the same name already present in the current class. */;
1217 error ("%q+D invalid in %q#T", using_decl, t);
1218 error (" because of local method %q+#D with same name",
1219 OVL_CURRENT (old_value));
1223 else if (!DECL_ARTIFICIAL (old_value))
1225 error ("%q+D invalid in %q#T", using_decl, t);
1226 error (" because of local member %q+#D with same name", old_value);
1230 /* Make type T see field decl FDECL with access ACCESS. */
1232 for (; flist; flist = OVL_NEXT (flist))
1234 add_method (t, OVL_CURRENT (flist), using_decl);
1235 alter_access (t, OVL_CURRENT (flist), access);
1238 alter_access (t, decl, access);
1241 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1242 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1243 properties of the bases. */
1246 check_bases (tree t,
1247 int* cant_have_const_ctor_p,
1248 int* no_const_asn_ref_p)
1251 int seen_non_virtual_nearly_empty_base_p;
1255 seen_non_virtual_nearly_empty_base_p = 0;
1257 for (binfo = TYPE_BINFO (t), i = 0;
1258 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1260 tree basetype = TREE_TYPE (base_binfo);
1262 gcc_assert (COMPLETE_TYPE_P (basetype));
1264 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1265 here because the case of virtual functions but non-virtual
1266 dtor is handled in finish_struct_1. */
1267 if (!TYPE_POLYMORPHIC_P (basetype))
1268 warning (OPT_Weffc__,
1269 "base class %q#T has a non-virtual destructor", basetype);
1271 /* If the base class doesn't have copy constructors or
1272 assignment operators that take const references, then the
1273 derived class cannot have such a member automatically
1275 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1276 *cant_have_const_ctor_p = 1;
1277 if (TYPE_HAS_ASSIGN_REF (basetype)
1278 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1279 *no_const_asn_ref_p = 1;
1281 if (BINFO_VIRTUAL_P (base_binfo))
1282 /* A virtual base does not effect nearly emptiness. */
1284 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1286 if (seen_non_virtual_nearly_empty_base_p)
1287 /* And if there is more than one nearly empty base, then the
1288 derived class is not nearly empty either. */
1289 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1291 /* Remember we've seen one. */
1292 seen_non_virtual_nearly_empty_base_p = 1;
1294 else if (!is_empty_class (basetype))
1295 /* If the base class is not empty or nearly empty, then this
1296 class cannot be nearly empty. */
1297 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1299 /* A lot of properties from the bases also apply to the derived
1301 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1302 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1303 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1304 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1305 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1306 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1307 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1308 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1309 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1310 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (basetype);
1314 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1315 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1316 that have had a nearly-empty virtual primary base stolen by some
1317 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1321 determine_primary_bases (tree t)
1324 tree primary = NULL_TREE;
1325 tree type_binfo = TYPE_BINFO (t);
1328 /* Determine the primary bases of our bases. */
1329 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1330 base_binfo = TREE_CHAIN (base_binfo))
1332 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1334 /* See if we're the non-virtual primary of our inheritance
1336 if (!BINFO_VIRTUAL_P (base_binfo))
1338 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1339 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1342 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1343 BINFO_TYPE (parent_primary)))
1344 /* We are the primary binfo. */
1345 BINFO_PRIMARY_P (base_binfo) = 1;
1347 /* Determine if we have a virtual primary base, and mark it so.
1349 if (primary && BINFO_VIRTUAL_P (primary))
1351 tree this_primary = copied_binfo (primary, base_binfo);
1353 if (BINFO_PRIMARY_P (this_primary))
1354 /* Someone already claimed this base. */
1355 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1360 BINFO_PRIMARY_P (this_primary) = 1;
1361 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1363 /* A virtual binfo might have been copied from within
1364 another hierarchy. As we're about to use it as a
1365 primary base, make sure the offsets match. */
1366 delta = size_diffop (convert (ssizetype,
1367 BINFO_OFFSET (base_binfo)),
1369 BINFO_OFFSET (this_primary)));
1371 propagate_binfo_offsets (this_primary, delta);
1376 /* First look for a dynamic direct non-virtual base. */
1377 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1379 tree basetype = BINFO_TYPE (base_binfo);
1381 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1383 primary = base_binfo;
1388 /* A "nearly-empty" virtual base class can be the primary base
1389 class, if no non-virtual polymorphic base can be found. Look for
1390 a nearly-empty virtual dynamic base that is not already a primary
1391 base of something in the hierarchy. If there is no such base,
1392 just pick the first nearly-empty virtual base. */
1394 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1395 base_binfo = TREE_CHAIN (base_binfo))
1396 if (BINFO_VIRTUAL_P (base_binfo)
1397 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1399 if (!BINFO_PRIMARY_P (base_binfo))
1401 /* Found one that is not primary. */
1402 primary = base_binfo;
1406 /* Remember the first candidate. */
1407 primary = base_binfo;
1411 /* If we've got a primary base, use it. */
1414 tree basetype = BINFO_TYPE (primary);
1416 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1417 if (BINFO_PRIMARY_P (primary))
1418 /* We are stealing a primary base. */
1419 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1420 BINFO_PRIMARY_P (primary) = 1;
1421 if (BINFO_VIRTUAL_P (primary))
1425 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1426 /* A virtual binfo might have been copied from within
1427 another hierarchy. As we're about to use it as a primary
1428 base, make sure the offsets match. */
1429 delta = size_diffop (ssize_int (0),
1430 convert (ssizetype, BINFO_OFFSET (primary)));
1432 propagate_binfo_offsets (primary, delta);
1435 primary = TYPE_BINFO (basetype);
1437 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1438 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1439 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1443 /* Set memoizing fields and bits of T (and its variants) for later
1447 finish_struct_bits (tree t)
1451 /* Fix up variants (if any). */
1452 for (variants = TYPE_NEXT_VARIANT (t);
1454 variants = TYPE_NEXT_VARIANT (variants))
1456 /* These fields are in the _TYPE part of the node, not in
1457 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1458 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1459 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1460 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1461 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1463 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1465 TYPE_BINFO (variants) = TYPE_BINFO (t);
1467 /* Copy whatever these are holding today. */
1468 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1469 TYPE_METHODS (variants) = TYPE_METHODS (t);
1470 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1472 /* All variants of a class have the same attributes. */
1473 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1476 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1477 /* For a class w/o baseclasses, 'finish_struct' has set
1478 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1479 Similarly for a class whose base classes do not have vtables.
1480 When neither of these is true, we might have removed abstract
1481 virtuals (by providing a definition), added some (by declaring
1482 new ones), or redeclared ones from a base class. We need to
1483 recalculate what's really an abstract virtual at this point (by
1484 looking in the vtables). */
1485 get_pure_virtuals (t);
1487 /* If this type has a copy constructor or a destructor, force its
1488 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1489 nonzero. This will cause it to be passed by invisible reference
1490 and prevent it from being returned in a register. */
1491 if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1494 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1495 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1497 TYPE_MODE (variants) = BLKmode;
1498 TREE_ADDRESSABLE (variants) = 1;
1503 /* Issue warnings about T having private constructors, but no friends,
1506 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1507 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1508 non-private static member functions. */
1511 maybe_warn_about_overly_private_class (tree t)
1513 int has_member_fn = 0;
1514 int has_nonprivate_method = 0;
1517 if (!warn_ctor_dtor_privacy
1518 /* If the class has friends, those entities might create and
1519 access instances, so we should not warn. */
1520 || (CLASSTYPE_FRIEND_CLASSES (t)
1521 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1522 /* We will have warned when the template was declared; there's
1523 no need to warn on every instantiation. */
1524 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1525 /* There's no reason to even consider warning about this
1529 /* We only issue one warning, if more than one applies, because
1530 otherwise, on code like:
1533 // Oops - forgot `public:'
1539 we warn several times about essentially the same problem. */
1541 /* Check to see if all (non-constructor, non-destructor) member
1542 functions are private. (Since there are no friends or
1543 non-private statics, we can't ever call any of the private member
1545 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1546 /* We're not interested in compiler-generated methods; they don't
1547 provide any way to call private members. */
1548 if (!DECL_ARTIFICIAL (fn))
1550 if (!TREE_PRIVATE (fn))
1552 if (DECL_STATIC_FUNCTION_P (fn))
1553 /* A non-private static member function is just like a
1554 friend; it can create and invoke private member
1555 functions, and be accessed without a class
1559 has_nonprivate_method = 1;
1560 /* Keep searching for a static member function. */
1562 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1566 if (!has_nonprivate_method && has_member_fn)
1568 /* There are no non-private methods, and there's at least one
1569 private member function that isn't a constructor or
1570 destructor. (If all the private members are
1571 constructors/destructors we want to use the code below that
1572 issues error messages specifically referring to
1573 constructors/destructors.) */
1575 tree binfo = TYPE_BINFO (t);
1577 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1578 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1580 has_nonprivate_method = 1;
1583 if (!has_nonprivate_method)
1585 warning (OPT_Wctor_dtor_privacy,
1586 "all member functions in class %qT are private", t);
1591 /* Even if some of the member functions are non-private, the class
1592 won't be useful for much if all the constructors or destructors
1593 are private: such an object can never be created or destroyed. */
1594 fn = CLASSTYPE_DESTRUCTORS (t);
1595 if (fn && TREE_PRIVATE (fn))
1597 warning (OPT_Wctor_dtor_privacy,
1598 "%q#T only defines a private destructor and has no friends",
1603 /* Warn about classes that have private constructors and no friends. */
1604 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1605 /* Implicitly generated constructors are always public. */
1606 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1607 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1609 int nonprivate_ctor = 0;
1611 /* If a non-template class does not define a copy
1612 constructor, one is defined for it, enabling it to avoid
1613 this warning. For a template class, this does not
1614 happen, and so we would normally get a warning on:
1616 template <class T> class C { private: C(); };
1618 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1619 complete non-template or fully instantiated classes have this
1621 if (!TYPE_HAS_INIT_REF (t))
1622 nonprivate_ctor = 1;
1624 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1626 tree ctor = OVL_CURRENT (fn);
1627 /* Ideally, we wouldn't count copy constructors (or, in
1628 fact, any constructor that takes an argument of the
1629 class type as a parameter) because such things cannot
1630 be used to construct an instance of the class unless
1631 you already have one. But, for now at least, we're
1633 if (! TREE_PRIVATE (ctor))
1635 nonprivate_ctor = 1;
1640 if (nonprivate_ctor == 0)
1642 warning (OPT_Wctor_dtor_privacy,
1643 "%q#T only defines private constructors and has no friends",
1651 gt_pointer_operator new_value;
1655 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1658 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;
1663 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1665 if (*m1 == NULL_TREE)
1667 if (*m2 == NULL_TREE)
1669 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1674 /* This routine compares two fields like method_name_cmp but using the
1675 pointer operator in resort_field_decl_data. */
1678 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1680 const tree *const m1 = (const tree *) m1_p;
1681 const tree *const m2 = (const tree *) m2_p;
1682 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1684 if (*m1 == NULL_TREE)
1686 if (*m2 == NULL_TREE)
1689 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1690 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1691 resort_data.new_value (&d1, resort_data.cookie);
1692 resort_data.new_value (&d2, resort_data.cookie);
1699 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1702 resort_type_method_vec (void* obj,
1703 void* orig_obj ATTRIBUTE_UNUSED ,
1704 gt_pointer_operator new_value,
1707 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1708 int len = VEC_length (tree, method_vec);
1712 /* The type conversion ops have to live at the front of the vec, so we
1714 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1715 VEC_iterate (tree, method_vec, slot, fn);
1717 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1722 resort_data.new_value = new_value;
1723 resort_data.cookie = cookie;
1724 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1725 resort_method_name_cmp);
1729 /* Warn about duplicate methods in fn_fields.
1731 Sort methods that are not special (i.e., constructors, destructors,
1732 and type conversion operators) so that we can find them faster in
1736 finish_struct_methods (tree t)
1739 VEC(tree,gc) *method_vec;
1742 method_vec = CLASSTYPE_METHOD_VEC (t);
1746 len = VEC_length (tree, method_vec);
1748 /* Clear DECL_IN_AGGR_P for all functions. */
1749 for (fn_fields = TYPE_METHODS (t); fn_fields;
1750 fn_fields = TREE_CHAIN (fn_fields))
1751 DECL_IN_AGGR_P (fn_fields) = 0;
1753 /* Issue warnings about private constructors and such. If there are
1754 no methods, then some public defaults are generated. */
1755 maybe_warn_about_overly_private_class (t);
1757 /* The type conversion ops have to live at the front of the vec, so we
1759 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1760 VEC_iterate (tree, method_vec, slot, fn_fields);
1762 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1765 qsort (VEC_address (tree, method_vec) + slot,
1766 len-slot, sizeof (tree), method_name_cmp);
1769 /* Make BINFO's vtable have N entries, including RTTI entries,
1770 vbase and vcall offsets, etc. Set its type and call the back end
1774 layout_vtable_decl (tree binfo, int n)
1779 atype = build_cplus_array_type (vtable_entry_type,
1780 build_index_type (size_int (n - 1)));
1781 layout_type (atype);
1783 /* We may have to grow the vtable. */
1784 vtable = get_vtbl_decl_for_binfo (binfo);
1785 if (!same_type_p (TREE_TYPE (vtable), atype))
1787 TREE_TYPE (vtable) = atype;
1788 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1789 layout_decl (vtable, 0);
1793 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1794 have the same signature. */
1797 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1799 /* One destructor overrides another if they are the same kind of
1801 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1802 && special_function_p (base_fndecl) == special_function_p (fndecl))
1804 /* But a non-destructor never overrides a destructor, nor vice
1805 versa, nor do different kinds of destructors override
1806 one-another. For example, a complete object destructor does not
1807 override a deleting destructor. */
1808 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1811 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1812 || (DECL_CONV_FN_P (fndecl)
1813 && DECL_CONV_FN_P (base_fndecl)
1814 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1815 DECL_CONV_FN_TYPE (base_fndecl))))
1817 tree types, base_types;
1818 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1819 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1820 if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1821 == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1822 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1828 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1832 base_derived_from (tree derived, tree base)
1836 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1838 if (probe == derived)
1840 else if (BINFO_VIRTUAL_P (probe))
1841 /* If we meet a virtual base, we can't follow the inheritance
1842 any more. See if the complete type of DERIVED contains
1843 such a virtual base. */
1844 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1850 typedef struct find_final_overrider_data_s {
1851 /* The function for which we are trying to find a final overrider. */
1853 /* The base class in which the function was declared. */
1854 tree declaring_base;
1855 /* The candidate overriders. */
1857 /* Path to most derived. */
1858 VEC(tree,heap) *path;
1859 } find_final_overrider_data;
1861 /* Add the overrider along the current path to FFOD->CANDIDATES.
1862 Returns true if an overrider was found; false otherwise. */
1865 dfs_find_final_overrider_1 (tree binfo,
1866 find_final_overrider_data *ffod,
1871 /* If BINFO is not the most derived type, try a more derived class.
1872 A definition there will overrider a definition here. */
1876 if (dfs_find_final_overrider_1
1877 (VEC_index (tree, ffod->path, depth), ffod, depth))
1881 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1884 tree *candidate = &ffod->candidates;
1886 /* Remove any candidates overridden by this new function. */
1889 /* If *CANDIDATE overrides METHOD, then METHOD
1890 cannot override anything else on the list. */
1891 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1893 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1894 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1895 *candidate = TREE_CHAIN (*candidate);
1897 candidate = &TREE_CHAIN (*candidate);
1900 /* Add the new function. */
1901 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1908 /* Called from find_final_overrider via dfs_walk. */
1911 dfs_find_final_overrider_pre (tree binfo, void *data)
1913 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1915 if (binfo == ffod->declaring_base)
1916 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1917 VEC_safe_push (tree, heap, ffod->path, binfo);
1923 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1925 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1926 VEC_pop (tree, ffod->path);
1931 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1932 FN and whose TREE_VALUE is the binfo for the base where the
1933 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1934 DERIVED) is the base object in which FN is declared. */
1937 find_final_overrider (tree derived, tree binfo, tree fn)
1939 find_final_overrider_data ffod;
1941 /* Getting this right is a little tricky. This is valid:
1943 struct S { virtual void f (); };
1944 struct T { virtual void f (); };
1945 struct U : public S, public T { };
1947 even though calling `f' in `U' is ambiguous. But,
1949 struct R { virtual void f(); };
1950 struct S : virtual public R { virtual void f (); };
1951 struct T : virtual public R { virtual void f (); };
1952 struct U : public S, public T { };
1954 is not -- there's no way to decide whether to put `S::f' or
1955 `T::f' in the vtable for `R'.
1957 The solution is to look at all paths to BINFO. If we find
1958 different overriders along any two, then there is a problem. */
1959 if (DECL_THUNK_P (fn))
1960 fn = THUNK_TARGET (fn);
1962 /* Determine the depth of the hierarchy. */
1964 ffod.declaring_base = binfo;
1965 ffod.candidates = NULL_TREE;
1966 ffod.path = VEC_alloc (tree, heap, 30);
1968 dfs_walk_all (derived, dfs_find_final_overrider_pre,
1969 dfs_find_final_overrider_post, &ffod);
1971 VEC_free (tree, heap, ffod.path);
1973 /* If there was no winner, issue an error message. */
1974 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
1975 return error_mark_node;
1977 return ffod.candidates;
1980 /* Return the index of the vcall offset for FN when TYPE is used as a
1984 get_vcall_index (tree fn, tree type)
1986 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
1990 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
1991 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
1992 || same_signature_p (fn, p->purpose))
1995 /* There should always be an appropriate index. */
1999 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2000 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
2001 corresponding position in the BINFO_VIRTUALS list. */
2004 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2012 tree overrider_fn, overrider_target;
2013 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2014 tree over_return, base_return;
2017 /* Find the nearest primary base (possibly binfo itself) which defines
2018 this function; this is the class the caller will convert to when
2019 calling FN through BINFO. */
2020 for (b = binfo; ; b = get_primary_binfo (b))
2023 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2026 /* The nearest definition is from a lost primary. */
2027 if (BINFO_LOST_PRIMARY_P (b))
2032 /* Find the final overrider. */
2033 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2034 if (overrider == error_mark_node)
2036 error ("no unique final overrider for %qD in %qT", target_fn, t);
2039 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2041 /* Check for adjusting covariant return types. */
2042 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2043 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2045 if (POINTER_TYPE_P (over_return)
2046 && TREE_CODE (over_return) == TREE_CODE (base_return)
2047 && CLASS_TYPE_P (TREE_TYPE (over_return))
2048 && CLASS_TYPE_P (TREE_TYPE (base_return))
2049 /* If the overrider is invalid, don't even try. */
2050 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2052 /* If FN is a covariant thunk, we must figure out the adjustment
2053 to the final base FN was converting to. As OVERRIDER_TARGET might
2054 also be converting to the return type of FN, we have to
2055 combine the two conversions here. */
2056 tree fixed_offset, virtual_offset;
2058 over_return = TREE_TYPE (over_return);
2059 base_return = TREE_TYPE (base_return);
2061 if (DECL_THUNK_P (fn))
2063 gcc_assert (DECL_RESULT_THUNK_P (fn));
2064 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2065 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2068 fixed_offset = virtual_offset = NULL_TREE;
2071 /* Find the equivalent binfo within the return type of the
2072 overriding function. We will want the vbase offset from
2074 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2076 else if (!same_type_ignoring_top_level_qualifiers_p
2077 (over_return, base_return))
2079 /* There was no existing virtual thunk (which takes
2080 precedence). So find the binfo of the base function's
2081 return type within the overriding function's return type.
2082 We cannot call lookup base here, because we're inside a
2083 dfs_walk, and will therefore clobber the BINFO_MARKED
2084 flags. Fortunately we know the covariancy is valid (it
2085 has already been checked), so we can just iterate along
2086 the binfos, which have been chained in inheritance graph
2087 order. Of course it is lame that we have to repeat the
2088 search here anyway -- we should really be caching pieces
2089 of the vtable and avoiding this repeated work. */
2090 tree thunk_binfo, base_binfo;
2092 /* Find the base binfo within the overriding function's
2093 return type. We will always find a thunk_binfo, except
2094 when the covariancy is invalid (which we will have
2095 already diagnosed). */
2096 for (base_binfo = TYPE_BINFO (base_return),
2097 thunk_binfo = TYPE_BINFO (over_return);
2099 thunk_binfo = TREE_CHAIN (thunk_binfo))
2100 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2101 BINFO_TYPE (base_binfo)))
2104 /* See if virtual inheritance is involved. */
2105 for (virtual_offset = thunk_binfo;
2107 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2108 if (BINFO_VIRTUAL_P (virtual_offset))
2112 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2114 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2118 /* We convert via virtual base. Adjust the fixed
2119 offset to be from there. */
2120 offset = size_diffop
2122 (ssizetype, BINFO_OFFSET (virtual_offset)));
2125 /* There was an existing fixed offset, this must be
2126 from the base just converted to, and the base the
2127 FN was thunking to. */
2128 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2130 fixed_offset = offset;
2134 if (fixed_offset || virtual_offset)
2135 /* Replace the overriding function with a covariant thunk. We
2136 will emit the overriding function in its own slot as
2138 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2139 fixed_offset, virtual_offset);
2142 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2143 !DECL_THUNK_P (fn));
2145 /* Assume that we will produce a thunk that convert all the way to
2146 the final overrider, and not to an intermediate virtual base. */
2147 virtual_base = NULL_TREE;
2149 /* See if we can convert to an intermediate virtual base first, and then
2150 use the vcall offset located there to finish the conversion. */
2151 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2153 /* If we find the final overrider, then we can stop
2155 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2156 BINFO_TYPE (TREE_VALUE (overrider))))
2159 /* If we find a virtual base, and we haven't yet found the
2160 overrider, then there is a virtual base between the
2161 declaring base (first_defn) and the final overrider. */
2162 if (BINFO_VIRTUAL_P (b))
2169 if (overrider_fn != overrider_target && !virtual_base)
2171 /* The ABI specifies that a covariant thunk includes a mangling
2172 for a this pointer adjustment. This-adjusting thunks that
2173 override a function from a virtual base have a vcall
2174 adjustment. When the virtual base in question is a primary
2175 virtual base, we know the adjustments are zero, (and in the
2176 non-covariant case, we would not use the thunk).
2177 Unfortunately we didn't notice this could happen, when
2178 designing the ABI and so never mandated that such a covariant
2179 thunk should be emitted. Because we must use the ABI mandated
2180 name, we must continue searching from the binfo where we
2181 found the most recent definition of the function, towards the
2182 primary binfo which first introduced the function into the
2183 vtable. If that enters a virtual base, we must use a vcall
2184 this-adjusting thunk. Bleah! */
2185 tree probe = first_defn;
2187 while ((probe = get_primary_binfo (probe))
2188 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2189 if (BINFO_VIRTUAL_P (probe))
2190 virtual_base = probe;
2193 /* Even if we find a virtual base, the correct delta is
2194 between the overrider and the binfo we're building a vtable
2196 goto virtual_covariant;
2199 /* Compute the constant adjustment to the `this' pointer. The
2200 `this' pointer, when this function is called, will point at BINFO
2201 (or one of its primary bases, which are at the same offset). */
2203 /* The `this' pointer needs to be adjusted from the declaration to
2204 the nearest virtual base. */
2205 delta = size_diffop (convert (ssizetype, BINFO_OFFSET (virtual_base)),
2206 convert (ssizetype, BINFO_OFFSET (first_defn)));
2208 /* If the nearest definition is in a lost primary, we don't need an
2209 entry in our vtable. Except possibly in a constructor vtable,
2210 if we happen to get our primary back. In that case, the offset
2211 will be zero, as it will be a primary base. */
2212 delta = size_zero_node;
2214 /* The `this' pointer needs to be adjusted from pointing to
2215 BINFO to pointing at the base where the final overrider
2218 delta = size_diffop (convert (ssizetype,
2219 BINFO_OFFSET (TREE_VALUE (overrider))),
2220 convert (ssizetype, BINFO_OFFSET (binfo)));
2222 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2225 BV_VCALL_INDEX (*virtuals)
2226 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2228 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2231 /* Called from modify_all_vtables via dfs_walk. */
2234 dfs_modify_vtables (tree binfo, void* data)
2236 tree t = (tree) data;
2241 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2242 /* A base without a vtable needs no modification, and its bases
2243 are uninteresting. */
2244 return dfs_skip_bases;
2246 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2247 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2248 /* Don't do the primary vtable, if it's new. */
2251 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2252 /* There's no need to modify the vtable for a non-virtual primary
2253 base; we're not going to use that vtable anyhow. We do still
2254 need to do this for virtual primary bases, as they could become
2255 non-primary in a construction vtable. */
2258 make_new_vtable (t, binfo);
2260 /* Now, go through each of the virtual functions in the virtual
2261 function table for BINFO. Find the final overrider, and update
2262 the BINFO_VIRTUALS list appropriately. */
2263 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2264 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2266 ix++, virtuals = TREE_CHAIN (virtuals),
2267 old_virtuals = TREE_CHAIN (old_virtuals))
2268 update_vtable_entry_for_fn (t,
2270 BV_FN (old_virtuals),
2276 /* Update all of the primary and secondary vtables for T. Create new
2277 vtables as required, and initialize their RTTI information. Each
2278 of the functions in VIRTUALS is declared in T and may override a
2279 virtual function from a base class; find and modify the appropriate
2280 entries to point to the overriding functions. Returns a list, in
2281 declaration order, of the virtual functions that are declared in T,
2282 but do not appear in the primary base class vtable, and which
2283 should therefore be appended to the end of the vtable for T. */
2286 modify_all_vtables (tree t, tree virtuals)
2288 tree binfo = TYPE_BINFO (t);
2291 /* Update all of the vtables. */
2292 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2294 /* Add virtual functions not already in our primary vtable. These
2295 will be both those introduced by this class, and those overridden
2296 from secondary bases. It does not include virtuals merely
2297 inherited from secondary bases. */
2298 for (fnsp = &virtuals; *fnsp; )
2300 tree fn = TREE_VALUE (*fnsp);
2302 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2303 || DECL_VINDEX (fn) == error_mark_node)
2305 /* We don't need to adjust the `this' pointer when
2306 calling this function. */
2307 BV_DELTA (*fnsp) = integer_zero_node;
2308 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2310 /* This is a function not already in our vtable. Keep it. */
2311 fnsp = &TREE_CHAIN (*fnsp);
2314 /* We've already got an entry for this function. Skip it. */
2315 *fnsp = TREE_CHAIN (*fnsp);
2321 /* Get the base virtual function declarations in T that have the
2325 get_basefndecls (tree name, tree t)
2328 tree base_fndecls = NULL_TREE;
2329 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2332 /* Find virtual functions in T with the indicated NAME. */
2333 i = lookup_fnfields_1 (t, name);
2335 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2337 methods = OVL_NEXT (methods))
2339 tree method = OVL_CURRENT (methods);
2341 if (TREE_CODE (method) == FUNCTION_DECL
2342 && DECL_VINDEX (method))
2343 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2347 return base_fndecls;
2349 for (i = 0; i < n_baseclasses; i++)
2351 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2352 base_fndecls = chainon (get_basefndecls (name, basetype),
2356 return base_fndecls;
2359 /* If this declaration supersedes the declaration of
2360 a method declared virtual in the base class, then
2361 mark this field as being virtual as well. */
2364 check_for_override (tree decl, tree ctype)
2366 if (TREE_CODE (decl) == TEMPLATE_DECL)
2367 /* In [temp.mem] we have:
2369 A specialization of a member function template does not
2370 override a virtual function from a base class. */
2372 if ((DECL_DESTRUCTOR_P (decl)
2373 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2374 || DECL_CONV_FN_P (decl))
2375 && look_for_overrides (ctype, decl)
2376 && !DECL_STATIC_FUNCTION_P (decl))
2377 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2378 the error_mark_node so that we know it is an overriding
2380 DECL_VINDEX (decl) = decl;
2382 if (DECL_VIRTUAL_P (decl))
2384 if (!DECL_VINDEX (decl))
2385 DECL_VINDEX (decl) = error_mark_node;
2386 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2390 /* Warn about hidden virtual functions that are not overridden in t.
2391 We know that constructors and destructors don't apply. */
2394 warn_hidden (tree t)
2396 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2400 /* We go through each separately named virtual function. */
2401 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2402 VEC_iterate (tree, method_vec, i, fns);
2413 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2414 have the same name. Figure out what name that is. */
2415 name = DECL_NAME (OVL_CURRENT (fns));
2416 /* There are no possibly hidden functions yet. */
2417 base_fndecls = NULL_TREE;
2418 /* Iterate through all of the base classes looking for possibly
2419 hidden functions. */
2420 for (binfo = TYPE_BINFO (t), j = 0;
2421 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2423 tree basetype = BINFO_TYPE (base_binfo);
2424 base_fndecls = chainon (get_basefndecls (name, basetype),
2428 /* If there are no functions to hide, continue. */
2432 /* Remove any overridden functions. */
2433 for (fn = fns; fn; fn = OVL_NEXT (fn))
2435 fndecl = OVL_CURRENT (fn);
2436 if (DECL_VINDEX (fndecl))
2438 tree *prev = &base_fndecls;
2441 /* If the method from the base class has the same
2442 signature as the method from the derived class, it
2443 has been overridden. */
2444 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2445 *prev = TREE_CHAIN (*prev);
2447 prev = &TREE_CHAIN (*prev);
2451 /* Now give a warning for all base functions without overriders,
2452 as they are hidden. */
2453 while (base_fndecls)
2455 /* Here we know it is a hider, and no overrider exists. */
2456 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2457 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2458 base_fndecls = TREE_CHAIN (base_fndecls);
2463 /* Check for things that are invalid. There are probably plenty of other
2464 things we should check for also. */
2467 finish_struct_anon (tree t)
2471 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2473 if (TREE_STATIC (field))
2475 if (TREE_CODE (field) != FIELD_DECL)
2478 if (DECL_NAME (field) == NULL_TREE
2479 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2481 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2482 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2483 for (; elt; elt = TREE_CHAIN (elt))
2485 /* We're generally only interested in entities the user
2486 declared, but we also find nested classes by noticing
2487 the TYPE_DECL that we create implicitly. You're
2488 allowed to put one anonymous union inside another,
2489 though, so we explicitly tolerate that. We use
2490 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2491 we also allow unnamed types used for defining fields. */
2492 if (DECL_ARTIFICIAL (elt)
2493 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2494 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2497 if (TREE_CODE (elt) != FIELD_DECL)
2500 permerror (input_location, "%q+#D invalid; an anonymous union can "
2501 "only have non-static data members", elt);
2503 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2504 "only have non-static data members", elt);
2508 if (TREE_PRIVATE (elt))
2511 permerror (input_location, "private member %q+#D in anonymous union", elt);
2513 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2515 else if (TREE_PROTECTED (elt))
2518 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2520 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2523 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2524 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2530 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2531 will be used later during class template instantiation.
2532 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2533 a non-static member data (FIELD_DECL), a member function
2534 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2535 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2536 When FRIEND_P is nonzero, T is either a friend class
2537 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2538 (FUNCTION_DECL, TEMPLATE_DECL). */
2541 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2543 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2544 if (CLASSTYPE_TEMPLATE_INFO (type))
2545 CLASSTYPE_DECL_LIST (type)
2546 = tree_cons (friend_p ? NULL_TREE : type,
2547 t, CLASSTYPE_DECL_LIST (type));
2550 /* Create default constructors, assignment operators, and so forth for
2551 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2552 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2553 the class cannot have a default constructor, copy constructor
2554 taking a const reference argument, or an assignment operator taking
2555 a const reference, respectively. */
2558 add_implicitly_declared_members (tree t,
2559 int cant_have_const_cctor,
2560 int cant_have_const_assignment)
2563 if (!CLASSTYPE_DESTRUCTORS (t))
2565 /* In general, we create destructors lazily. */
2566 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2567 /* However, if the implicit destructor is non-trivial
2568 destructor, we sometimes have to create it at this point. */
2569 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2573 if (TYPE_FOR_JAVA (t))
2574 /* If this a Java class, any non-trivial destructor is
2575 invalid, even if compiler-generated. Therefore, if the
2576 destructor is non-trivial we create it now. */
2584 /* If the implicit destructor will be virtual, then we must
2585 generate it now because (unfortunately) we do not
2586 generate virtual tables lazily. */
2587 binfo = TYPE_BINFO (t);
2588 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2593 base_type = BINFO_TYPE (base_binfo);
2594 dtor = CLASSTYPE_DESTRUCTORS (base_type);
2595 if (dtor && DECL_VIRTUAL_P (dtor))
2603 /* If we can't get away with being lazy, generate the destructor
2606 lazily_declare_fn (sfk_destructor, t);
2612 If there is no user-declared constructor for a class, a default
2613 constructor is implicitly declared. */
2614 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2616 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2617 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2622 If a class definition does not explicitly declare a copy
2623 constructor, one is declared implicitly. */
2624 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2626 TYPE_HAS_INIT_REF (t) = 1;
2627 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2628 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2631 /* If there is no assignment operator, one will be created if and
2632 when it is needed. For now, just record whether or not the type
2633 of the parameter to the assignment operator will be a const or
2634 non-const reference. */
2635 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2637 TYPE_HAS_ASSIGN_REF (t) = 1;
2638 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2639 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2643 /* Subroutine of finish_struct_1. Recursively count the number of fields
2644 in TYPE, including anonymous union members. */
2647 count_fields (tree fields)
2651 for (x = fields; x; x = TREE_CHAIN (x))
2653 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2654 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2661 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2662 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2665 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2668 for (x = fields; x; x = TREE_CHAIN (x))
2670 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2671 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2673 field_vec->elts[idx++] = x;
2678 /* FIELD is a bit-field. We are finishing the processing for its
2679 enclosing type. Issue any appropriate messages and set appropriate
2680 flags. Returns false if an error has been diagnosed. */
2683 check_bitfield_decl (tree field)
2685 tree type = TREE_TYPE (field);
2688 /* Extract the declared width of the bitfield, which has been
2689 temporarily stashed in DECL_INITIAL. */
2690 w = DECL_INITIAL (field);
2691 gcc_assert (w != NULL_TREE);
2692 /* Remove the bit-field width indicator so that the rest of the
2693 compiler does not treat that value as an initializer. */
2694 DECL_INITIAL (field) = NULL_TREE;
2696 /* Detect invalid bit-field type. */
2697 if (!INTEGRAL_TYPE_P (type))
2699 error ("bit-field %q+#D with non-integral type", field);
2700 w = error_mark_node;
2704 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2707 /* detect invalid field size. */
2708 w = integral_constant_value (w);
2710 if (TREE_CODE (w) != INTEGER_CST)
2712 error ("bit-field %q+D width not an integer constant", field);
2713 w = error_mark_node;
2715 else if (tree_int_cst_sgn (w) < 0)
2717 error ("negative width in bit-field %q+D", field);
2718 w = error_mark_node;
2720 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2722 error ("zero width for bit-field %q+D", field);
2723 w = error_mark_node;
2725 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2726 && TREE_CODE (type) != ENUMERAL_TYPE
2727 && TREE_CODE (type) != BOOLEAN_TYPE)
2728 warning (0, "width of %q+D exceeds its type", field);
2729 else if (TREE_CODE (type) == ENUMERAL_TYPE
2730 && (0 > compare_tree_int (w,
2731 tree_int_cst_min_precision
2732 (TYPE_MIN_VALUE (type),
2733 TYPE_UNSIGNED (type)))
2734 || 0 > compare_tree_int (w,
2735 tree_int_cst_min_precision
2736 (TYPE_MAX_VALUE (type),
2737 TYPE_UNSIGNED (type)))))
2738 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2741 if (w != error_mark_node)
2743 DECL_SIZE (field) = convert (bitsizetype, w);
2744 DECL_BIT_FIELD (field) = 1;
2749 /* Non-bit-fields are aligned for their type. */
2750 DECL_BIT_FIELD (field) = 0;
2751 CLEAR_DECL_C_BIT_FIELD (field);
2756 /* FIELD is a non bit-field. We are finishing the processing for its
2757 enclosing type T. Issue any appropriate messages and set appropriate
2761 check_field_decl (tree field,
2763 int* cant_have_const_ctor,
2764 int* no_const_asn_ref,
2765 int* any_default_members)
2767 tree type = strip_array_types (TREE_TYPE (field));
2769 /* An anonymous union cannot contain any fields which would change
2770 the settings of CANT_HAVE_CONST_CTOR and friends. */
2771 if (ANON_UNION_TYPE_P (type))
2773 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2774 structs. So, we recurse through their fields here. */
2775 else if (ANON_AGGR_TYPE_P (type))
2779 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2780 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2781 check_field_decl (fields, t, cant_have_const_ctor,
2782 no_const_asn_ref, any_default_members);
2784 /* Check members with class type for constructors, destructors,
2786 else if (CLASS_TYPE_P (type))
2788 /* Never let anything with uninheritable virtuals
2789 make it through without complaint. */
2790 abstract_virtuals_error (field, type);
2792 if (TREE_CODE (t) == UNION_TYPE)
2794 if (TYPE_NEEDS_CONSTRUCTING (type))
2795 error ("member %q+#D with constructor not allowed in union",
2797 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2798 error ("member %q+#D with destructor not allowed in union", field);
2799 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2800 error ("member %q+#D with copy assignment operator not allowed in union",
2805 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2806 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2807 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2808 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2809 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2810 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (type);
2813 if (!TYPE_HAS_CONST_INIT_REF (type))
2814 *cant_have_const_ctor = 1;
2816 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2817 *no_const_asn_ref = 1;
2819 if (DECL_INITIAL (field) != NULL_TREE)
2821 /* `build_class_init_list' does not recognize
2823 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2824 error ("multiple fields in union %qT initialized", t);
2825 *any_default_members = 1;
2829 /* Check the data members (both static and non-static), class-scoped
2830 typedefs, etc., appearing in the declaration of T. Issue
2831 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2832 declaration order) of access declarations; each TREE_VALUE in this
2833 list is a USING_DECL.
2835 In addition, set the following flags:
2838 The class is empty, i.e., contains no non-static data members.
2840 CANT_HAVE_CONST_CTOR_P
2841 This class cannot have an implicitly generated copy constructor
2842 taking a const reference.
2844 CANT_HAVE_CONST_ASN_REF
2845 This class cannot have an implicitly generated assignment
2846 operator taking a const reference.
2848 All of these flags should be initialized before calling this
2851 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2852 fields can be added by adding to this chain. */
2855 check_field_decls (tree t, tree *access_decls,
2856 int *cant_have_const_ctor_p,
2857 int *no_const_asn_ref_p)
2862 int any_default_members;
2865 /* Assume there are no access declarations. */
2866 *access_decls = NULL_TREE;
2867 /* Assume this class has no pointer members. */
2868 has_pointers = false;
2869 /* Assume none of the members of this class have default
2871 any_default_members = 0;
2873 for (field = &TYPE_FIELDS (t); *field; field = next)
2876 tree type = TREE_TYPE (x);
2878 next = &TREE_CHAIN (x);
2880 if (TREE_CODE (x) == USING_DECL)
2882 /* Prune the access declaration from the list of fields. */
2883 *field = TREE_CHAIN (x);
2885 /* Save the access declarations for our caller. */
2886 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2888 /* Since we've reset *FIELD there's no reason to skip to the
2894 if (TREE_CODE (x) == TYPE_DECL
2895 || TREE_CODE (x) == TEMPLATE_DECL)
2898 /* If we've gotten this far, it's a data member, possibly static,
2899 or an enumerator. */
2900 DECL_CONTEXT (x) = t;
2902 /* When this goes into scope, it will be a non-local reference. */
2903 DECL_NONLOCAL (x) = 1;
2905 if (TREE_CODE (t) == UNION_TYPE)
2909 If a union contains a static data member, or a member of
2910 reference type, the program is ill-formed. */
2911 if (TREE_CODE (x) == VAR_DECL)
2913 error ("%q+D may not be static because it is a member of a union", x);
2916 if (TREE_CODE (type) == REFERENCE_TYPE)
2918 error ("%q+D may not have reference type %qT because"
2919 " it is a member of a union",
2925 /* Perform error checking that did not get done in
2927 if (TREE_CODE (type) == FUNCTION_TYPE)
2929 error ("field %q+D invalidly declared function type", x);
2930 type = build_pointer_type (type);
2931 TREE_TYPE (x) = type;
2933 else if (TREE_CODE (type) == METHOD_TYPE)
2935 error ("field %q+D invalidly declared method type", x);
2936 type = build_pointer_type (type);
2937 TREE_TYPE (x) = type;
2940 if (type == error_mark_node)
2943 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
2946 /* Now it can only be a FIELD_DECL. */
2948 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
2949 CLASSTYPE_NON_AGGREGATE (t) = 1;
2951 /* If this is of reference type, check if it needs an init. */
2952 if (TREE_CODE (type) == REFERENCE_TYPE)
2954 CLASSTYPE_NON_POD_P (t) = 1;
2955 if (DECL_INITIAL (x) == NULL_TREE)
2956 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2958 /* ARM $12.6.2: [A member initializer list] (or, for an
2959 aggregate, initialization by a brace-enclosed list) is the
2960 only way to initialize nonstatic const and reference
2962 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2965 type = strip_array_types (type);
2967 if (TYPE_PACKED (t))
2969 if (!pod_type_p (type) && !TYPE_PACKED (type))
2973 "ignoring packed attribute because of unpacked non-POD field %q+#D",
2977 else if (TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
2978 DECL_PACKED (x) = 1;
2981 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
2982 /* We don't treat zero-width bitfields as making a class
2987 /* The class is non-empty. */
2988 CLASSTYPE_EMPTY_P (t) = 0;
2989 /* The class is not even nearly empty. */
2990 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
2991 /* If one of the data members contains an empty class,
2993 if (CLASS_TYPE_P (type)
2994 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
2995 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
2998 /* This is used by -Weffc++ (see below). Warn only for pointers
2999 to members which might hold dynamic memory. So do not warn
3000 for pointers to functions or pointers to members. */
3001 if (TYPE_PTR_P (type)
3002 && !TYPE_PTRFN_P (type)
3003 && !TYPE_PTR_TO_MEMBER_P (type))
3004 has_pointers = true;
3006 if (CLASS_TYPE_P (type))
3008 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3009 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3010 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3011 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3014 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3015 CLASSTYPE_HAS_MUTABLE (t) = 1;
3017 if (! pod_type_p (type))
3018 /* DR 148 now allows pointers to members (which are POD themselves),
3019 to be allowed in POD structs. */
3020 CLASSTYPE_NON_POD_P (t) = 1;
3022 if (! zero_init_p (type))
3023 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3025 /* If any field is const, the structure type is pseudo-const. */
3026 if (CP_TYPE_CONST_P (type))
3028 C_TYPE_FIELDS_READONLY (t) = 1;
3029 if (DECL_INITIAL (x) == NULL_TREE)
3030 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3032 /* ARM $12.6.2: [A member initializer list] (or, for an
3033 aggregate, initialization by a brace-enclosed list) is the
3034 only way to initialize nonstatic const and reference
3036 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3038 /* A field that is pseudo-const makes the structure likewise. */
3039 else if (CLASS_TYPE_P (type))
3041 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3042 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3043 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3044 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3047 /* Core issue 80: A nonstatic data member is required to have a
3048 different name from the class iff the class has a
3049 user-declared constructor. */
3050 if (constructor_name_p (DECL_NAME (x), t)
3051 && TYPE_HAS_USER_CONSTRUCTOR (t))
3052 permerror (input_location, "field %q+#D with same name as class", x);
3054 /* We set DECL_C_BIT_FIELD in grokbitfield.
3055 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3056 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3057 check_field_decl (x, t,
3058 cant_have_const_ctor_p,
3060 &any_default_members);
3063 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3064 it should also define a copy constructor and an assignment operator to
3065 implement the correct copy semantic (deep vs shallow, etc.). As it is
3066 not feasible to check whether the constructors do allocate dynamic memory
3067 and store it within members, we approximate the warning like this:
3069 -- Warn only if there are members which are pointers
3070 -- Warn only if there is a non-trivial constructor (otherwise,
3071 there cannot be memory allocated).
3072 -- Warn only if there is a non-trivial destructor. We assume that the
3073 user at least implemented the cleanup correctly, and a destructor
3074 is needed to free dynamic memory.
3076 This seems enough for practical purposes. */
3079 && TYPE_HAS_USER_CONSTRUCTOR (t)
3080 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3081 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3083 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3085 if (! TYPE_HAS_INIT_REF (t))
3087 warning (OPT_Weffc__,
3088 " but does not override %<%T(const %T&)%>", t, t);
3089 if (!TYPE_HAS_ASSIGN_REF (t))
3090 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3092 else if (! TYPE_HAS_ASSIGN_REF (t))
3093 warning (OPT_Weffc__,
3094 " but does not override %<operator=(const %T&)%>", t);
3097 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3099 TYPE_PACKED (t) = 0;
3101 /* Check anonymous struct/anonymous union fields. */
3102 finish_struct_anon (t);
3104 /* We've built up the list of access declarations in reverse order.
3106 *access_decls = nreverse (*access_decls);
3109 /* If TYPE is an empty class type, records its OFFSET in the table of
3113 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3117 if (!is_empty_class (type))
3120 /* Record the location of this empty object in OFFSETS. */
3121 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3123 n = splay_tree_insert (offsets,
3124 (splay_tree_key) offset,
3125 (splay_tree_value) NULL_TREE);
3126 n->value = ((splay_tree_value)
3127 tree_cons (NULL_TREE,
3134 /* Returns nonzero if TYPE is an empty class type and there is
3135 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3138 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3143 if (!is_empty_class (type))
3146 /* Record the location of this empty object in OFFSETS. */
3147 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3151 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3152 if (same_type_p (TREE_VALUE (t), type))
3158 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3159 F for every subobject, passing it the type, offset, and table of
3160 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3163 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3164 than MAX_OFFSET will not be walked.
3166 If F returns a nonzero value, the traversal ceases, and that value
3167 is returned. Otherwise, returns zero. */
3170 walk_subobject_offsets (tree type,
3171 subobject_offset_fn f,
3178 tree type_binfo = NULL_TREE;
3180 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3182 if (max_offset && INT_CST_LT (max_offset, offset))
3185 if (type == error_mark_node)
3190 if (abi_version_at_least (2))
3192 type = BINFO_TYPE (type);
3195 if (CLASS_TYPE_P (type))
3201 /* Avoid recursing into objects that are not interesting. */
3202 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3205 /* Record the location of TYPE. */
3206 r = (*f) (type, offset, offsets);
3210 /* Iterate through the direct base classes of TYPE. */
3212 type_binfo = TYPE_BINFO (type);
3213 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3217 if (abi_version_at_least (2)
3218 && BINFO_VIRTUAL_P (binfo))
3222 && BINFO_VIRTUAL_P (binfo)
3223 && !BINFO_PRIMARY_P (binfo))
3226 if (!abi_version_at_least (2))
3227 binfo_offset = size_binop (PLUS_EXPR,
3229 BINFO_OFFSET (binfo));
3233 /* We cannot rely on BINFO_OFFSET being set for the base
3234 class yet, but the offsets for direct non-virtual
3235 bases can be calculated by going back to the TYPE. */
3236 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3237 binfo_offset = size_binop (PLUS_EXPR,
3239 BINFO_OFFSET (orig_binfo));
3242 r = walk_subobject_offsets (binfo,
3247 (abi_version_at_least (2)
3248 ? /*vbases_p=*/0 : vbases_p));
3253 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3256 VEC(tree,gc) *vbases;
3258 /* Iterate through the virtual base classes of TYPE. In G++
3259 3.2, we included virtual bases in the direct base class
3260 loop above, which results in incorrect results; the
3261 correct offsets for virtual bases are only known when
3262 working with the most derived type. */
3264 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3265 VEC_iterate (tree, vbases, ix, binfo); ix++)
3267 r = walk_subobject_offsets (binfo,
3269 size_binop (PLUS_EXPR,
3271 BINFO_OFFSET (binfo)),
3280 /* We still have to walk the primary base, if it is
3281 virtual. (If it is non-virtual, then it was walked
3283 tree vbase = get_primary_binfo (type_binfo);
3285 if (vbase && BINFO_VIRTUAL_P (vbase)
3286 && BINFO_PRIMARY_P (vbase)
3287 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3289 r = (walk_subobject_offsets
3291 offsets, max_offset, /*vbases_p=*/0));
3298 /* Iterate through the fields of TYPE. */
3299 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3300 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3304 if (abi_version_at_least (2))
3305 field_offset = byte_position (field);
3307 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3308 field_offset = DECL_FIELD_OFFSET (field);
3310 r = walk_subobject_offsets (TREE_TYPE (field),
3312 size_binop (PLUS_EXPR,
3322 else if (TREE_CODE (type) == ARRAY_TYPE)
3324 tree element_type = strip_array_types (type);
3325 tree domain = TYPE_DOMAIN (type);
3328 /* Avoid recursing into objects that are not interesting. */
3329 if (!CLASS_TYPE_P (element_type)
3330 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3333 /* Step through each of the elements in the array. */
3334 for (index = size_zero_node;
3335 /* G++ 3.2 had an off-by-one error here. */
3336 (abi_version_at_least (2)
3337 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3338 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3339 index = size_binop (PLUS_EXPR, index, size_one_node))
3341 r = walk_subobject_offsets (TREE_TYPE (type),
3349 offset = size_binop (PLUS_EXPR, offset,
3350 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3351 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3352 there's no point in iterating through the remaining
3353 elements of the array. */
3354 if (max_offset && INT_CST_LT (max_offset, offset))
3362 /* Record all of the empty subobjects of TYPE (either a type or a
3363 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3364 is being placed at OFFSET; otherwise, it is a base class that is
3365 being placed at OFFSET. */
3368 record_subobject_offsets (tree type,
3371 bool is_data_member)
3374 /* If recording subobjects for a non-static data member or a
3375 non-empty base class , we do not need to record offsets beyond
3376 the size of the biggest empty class. Additional data members
3377 will go at the end of the class. Additional base classes will go
3378 either at offset zero (if empty, in which case they cannot
3379 overlap with offsets past the size of the biggest empty class) or
3380 at the end of the class.
3382 However, if we are placing an empty base class, then we must record
3383 all offsets, as either the empty class is at offset zero (where
3384 other empty classes might later be placed) or at the end of the
3385 class (where other objects might then be placed, so other empty
3386 subobjects might later overlap). */
3388 || !is_empty_class (BINFO_TYPE (type)))
3389 max_offset = sizeof_biggest_empty_class;
3391 max_offset = NULL_TREE;
3392 walk_subobject_offsets (type, record_subobject_offset, offset,
3393 offsets, max_offset, is_data_member);
3396 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3397 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3398 virtual bases of TYPE are examined. */
3401 layout_conflict_p (tree type,
3406 splay_tree_node max_node;
3408 /* Get the node in OFFSETS that indicates the maximum offset where
3409 an empty subobject is located. */
3410 max_node = splay_tree_max (offsets);
3411 /* If there aren't any empty subobjects, then there's no point in
3412 performing this check. */
3416 return walk_subobject_offsets (type, check_subobject_offset, offset,
3417 offsets, (tree) (max_node->key),
3421 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3422 non-static data member of the type indicated by RLI. BINFO is the
3423 binfo corresponding to the base subobject, OFFSETS maps offsets to
3424 types already located at those offsets. This function determines
3425 the position of the DECL. */
3428 layout_nonempty_base_or_field (record_layout_info rli,
3433 tree offset = NULL_TREE;
3439 /* For the purposes of determining layout conflicts, we want to
3440 use the class type of BINFO; TREE_TYPE (DECL) will be the
3441 CLASSTYPE_AS_BASE version, which does not contain entries for
3442 zero-sized bases. */
3443 type = TREE_TYPE (binfo);
3448 type = TREE_TYPE (decl);
3452 /* Try to place the field. It may take more than one try if we have
3453 a hard time placing the field without putting two objects of the
3454 same type at the same address. */
3457 struct record_layout_info_s old_rli = *rli;
3459 /* Place this field. */
3460 place_field (rli, decl);
3461 offset = byte_position (decl);
3463 /* We have to check to see whether or not there is already
3464 something of the same type at the offset we're about to use.
3465 For example, consider:
3468 struct T : public S { int i; };
3469 struct U : public S, public T {};
3471 Here, we put S at offset zero in U. Then, we can't put T at
3472 offset zero -- its S component would be at the same address
3473 as the S we already allocated. So, we have to skip ahead.
3474 Since all data members, including those whose type is an
3475 empty class, have nonzero size, any overlap can happen only
3476 with a direct or indirect base-class -- it can't happen with
3478 /* In a union, overlap is permitted; all members are placed at
3480 if (TREE_CODE (rli->t) == UNION_TYPE)
3482 /* G++ 3.2 did not check for overlaps when placing a non-empty
3484 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3486 if (layout_conflict_p (field_p ? type : binfo, offset,
3489 /* Strip off the size allocated to this field. That puts us
3490 at the first place we could have put the field with
3491 proper alignment. */
3494 /* Bump up by the alignment required for the type. */
3496 = size_binop (PLUS_EXPR, rli->bitpos,
3498 ? CLASSTYPE_ALIGN (type)
3499 : TYPE_ALIGN (type)));
3500 normalize_rli (rli);
3503 /* There was no conflict. We're done laying out this field. */
3507 /* Now that we know where it will be placed, update its
3509 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3510 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3511 this point because their BINFO_OFFSET is copied from another
3512 hierarchy. Therefore, we may not need to add the entire
3514 propagate_binfo_offsets (binfo,
3515 size_diffop (convert (ssizetype, offset),
3517 BINFO_OFFSET (binfo))));
3520 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3523 empty_base_at_nonzero_offset_p (tree type,
3525 splay_tree offsets ATTRIBUTE_UNUSED)
3527 return is_empty_class (type) && !integer_zerop (offset);
3530 /* Layout the empty base BINFO. EOC indicates the byte currently just
3531 past the end of the class, and should be correctly aligned for a
3532 class of the type indicated by BINFO; OFFSETS gives the offsets of
3533 the empty bases allocated so far. T is the most derived
3534 type. Return nonzero iff we added it at the end. */
3537 layout_empty_base (record_layout_info rli, tree binfo,
3538 tree eoc, splay_tree offsets)
3541 tree basetype = BINFO_TYPE (binfo);
3544 /* This routine should only be used for empty classes. */
3545 gcc_assert (is_empty_class (basetype));
3546 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3548 if (!integer_zerop (BINFO_OFFSET (binfo)))
3550 if (abi_version_at_least (2))
3551 propagate_binfo_offsets
3552 (binfo, size_diffop (size_zero_node, BINFO_OFFSET (binfo)));
3555 "offset of empty base %qT may not be ABI-compliant and may"
3556 "change in a future version of GCC",
3557 BINFO_TYPE (binfo));
3560 /* This is an empty base class. We first try to put it at offset
3562 if (layout_conflict_p (binfo,
3563 BINFO_OFFSET (binfo),
3567 /* That didn't work. Now, we move forward from the next
3568 available spot in the class. */
3570 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3573 if (!layout_conflict_p (binfo,
3574 BINFO_OFFSET (binfo),
3577 /* We finally found a spot where there's no overlap. */
3580 /* There's overlap here, too. Bump along to the next spot. */
3581 propagate_binfo_offsets (binfo, alignment);
3585 if (CLASSTYPE_USER_ALIGN (basetype))
3587 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3589 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3590 TYPE_USER_ALIGN (rli->t) = 1;
3596 /* Layout the base given by BINFO in the class indicated by RLI.
3597 *BASE_ALIGN is a running maximum of the alignments of
3598 any base class. OFFSETS gives the location of empty base
3599 subobjects. T is the most derived type. Return nonzero if the new
3600 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3601 *NEXT_FIELD, unless BINFO is for an empty base class.
3603 Returns the location at which the next field should be inserted. */
3606 build_base_field (record_layout_info rli, tree binfo,
3607 splay_tree offsets, tree *next_field)
3610 tree basetype = BINFO_TYPE (binfo);
3612 if (!COMPLETE_TYPE_P (basetype))
3613 /* This error is now reported in xref_tag, thus giving better
3614 location information. */
3617 /* Place the base class. */
3618 if (!is_empty_class (basetype))
3622 /* The containing class is non-empty because it has a non-empty
3624 CLASSTYPE_EMPTY_P (t) = 0;
3626 /* Create the FIELD_DECL. */
3627 decl = build_decl (FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3628 DECL_ARTIFICIAL (decl) = 1;
3629 DECL_IGNORED_P (decl) = 1;
3630 DECL_FIELD_CONTEXT (decl) = t;
3631 if (CLASSTYPE_AS_BASE (basetype))
3633 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3634 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3635 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3636 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3637 DECL_MODE (decl) = TYPE_MODE (basetype);
3638 DECL_FIELD_IS_BASE (decl) = 1;
3640 /* Try to place the field. It may take more than one try if we
3641 have a hard time placing the field without putting two
3642 objects of the same type at the same address. */
3643 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3644 /* Add the new FIELD_DECL to the list of fields for T. */
3645 TREE_CHAIN (decl) = *next_field;
3647 next_field = &TREE_CHAIN (decl);
3655 /* On some platforms (ARM), even empty classes will not be
3657 eoc = round_up (rli_size_unit_so_far (rli),
3658 CLASSTYPE_ALIGN_UNIT (basetype));
3659 atend = layout_empty_base (rli, binfo, eoc, offsets);
3660 /* A nearly-empty class "has no proper base class that is empty,
3661 not morally virtual, and at an offset other than zero." */
3662 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3665 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3666 /* The check above (used in G++ 3.2) is insufficient because
3667 an empty class placed at offset zero might itself have an
3668 empty base at a nonzero offset. */
3669 else if (walk_subobject_offsets (basetype,
3670 empty_base_at_nonzero_offset_p,
3673 /*max_offset=*/NULL_TREE,
3676 if (abi_version_at_least (2))
3677 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3680 "class %qT will be considered nearly empty in a "
3681 "future version of GCC", t);
3685 /* We do not create a FIELD_DECL for empty base classes because
3686 it might overlap some other field. We want to be able to
3687 create CONSTRUCTORs for the class by iterating over the
3688 FIELD_DECLs, and the back end does not handle overlapping
3691 /* An empty virtual base causes a class to be non-empty
3692 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3693 here because that was already done when the virtual table
3694 pointer was created. */
3697 /* Record the offsets of BINFO and its base subobjects. */
3698 record_subobject_offsets (binfo,
3699 BINFO_OFFSET (binfo),
3701 /*is_data_member=*/false);
3706 /* Layout all of the non-virtual base classes. Record empty
3707 subobjects in OFFSETS. T is the most derived type. Return nonzero
3708 if the type cannot be nearly empty. The fields created
3709 corresponding to the base classes will be inserted at
3713 build_base_fields (record_layout_info rli,
3714 splay_tree offsets, tree *next_field)
3716 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3719 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3722 /* The primary base class is always allocated first. */
3723 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3724 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3725 offsets, next_field);
3727 /* Now allocate the rest of the bases. */
3728 for (i = 0; i < n_baseclasses; ++i)
3732 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3734 /* The primary base was already allocated above, so we don't
3735 need to allocate it again here. */
3736 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3739 /* Virtual bases are added at the end (a primary virtual base
3740 will have already been added). */
3741 if (BINFO_VIRTUAL_P (base_binfo))
3744 next_field = build_base_field (rli, base_binfo,
3745 offsets, next_field);
3749 /* Go through the TYPE_METHODS of T issuing any appropriate
3750 diagnostics, figuring out which methods override which other
3751 methods, and so forth. */
3754 check_methods (tree t)
3758 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3760 check_for_override (x, t);
3761 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3762 error ("initializer specified for non-virtual method %q+D", x);
3763 /* The name of the field is the original field name
3764 Save this in auxiliary field for later overloading. */
3765 if (DECL_VINDEX (x))
3767 TYPE_POLYMORPHIC_P (t) = 1;
3768 if (DECL_PURE_VIRTUAL_P (x))
3769 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3771 /* All user-provided destructors are non-trivial. */
3772 if (DECL_DESTRUCTOR_P (x) && !DECL_DEFAULTED_FN (x))
3773 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3777 /* FN is a constructor or destructor. Clone the declaration to create
3778 a specialized in-charge or not-in-charge version, as indicated by
3782 build_clone (tree fn, tree name)
3787 /* Copy the function. */
3788 clone = copy_decl (fn);
3789 /* Remember where this function came from. */
3790 DECL_CLONED_FUNCTION (clone) = fn;
3791 DECL_ABSTRACT_ORIGIN (clone) = fn;
3792 /* Reset the function name. */
3793 DECL_NAME (clone) = name;
3794 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3795 /* There's no pending inline data for this function. */
3796 DECL_PENDING_INLINE_INFO (clone) = NULL;
3797 DECL_PENDING_INLINE_P (clone) = 0;
3798 /* And it hasn't yet been deferred. */
3799 DECL_DEFERRED_FN (clone) = 0;
3801 /* The base-class destructor is not virtual. */
3802 if (name == base_dtor_identifier)
3804 DECL_VIRTUAL_P (clone) = 0;
3805 if (TREE_CODE (clone) != TEMPLATE_DECL)
3806 DECL_VINDEX (clone) = NULL_TREE;
3809 /* If there was an in-charge parameter, drop it from the function
3811 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3817 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3818 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3819 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3820 /* Skip the `this' parameter. */
3821 parmtypes = TREE_CHAIN (parmtypes);
3822 /* Skip the in-charge parameter. */
3823 parmtypes = TREE_CHAIN (parmtypes);
3824 /* And the VTT parm, in a complete [cd]tor. */
3825 if (DECL_HAS_VTT_PARM_P (fn)
3826 && ! DECL_NEEDS_VTT_PARM_P (clone))
3827 parmtypes = TREE_CHAIN (parmtypes);
3828 /* If this is subobject constructor or destructor, add the vtt
3831 = build_method_type_directly (basetype,
3832 TREE_TYPE (TREE_TYPE (clone)),
3835 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3838 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3839 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3842 /* Copy the function parameters. But, DECL_ARGUMENTS on a TEMPLATE_DECL
3843 aren't function parameters; those are the template parameters. */
3844 if (TREE_CODE (clone) != TEMPLATE_DECL)
3846 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3847 /* Remove the in-charge parameter. */
3848 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3850 TREE_CHAIN (DECL_ARGUMENTS (clone))
3851 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3852 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3854 /* And the VTT parm, in a complete [cd]tor. */
3855 if (DECL_HAS_VTT_PARM_P (fn))
3857 if (DECL_NEEDS_VTT_PARM_P (clone))
3858 DECL_HAS_VTT_PARM_P (clone) = 1;
3861 TREE_CHAIN (DECL_ARGUMENTS (clone))
3862 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3863 DECL_HAS_VTT_PARM_P (clone) = 0;
3867 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3869 DECL_CONTEXT (parms) = clone;
3870 cxx_dup_lang_specific_decl (parms);
3874 /* Create the RTL for this function. */
3875 SET_DECL_RTL (clone, NULL_RTX);
3876 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3878 /* Make it easy to find the CLONE given the FN. */
3879 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3880 TREE_CHAIN (fn) = clone;
3882 /* If this is a template, handle the DECL_TEMPLATE_RESULT as well. */
3883 if (TREE_CODE (clone) == TEMPLATE_DECL)
3887 DECL_TEMPLATE_RESULT (clone)
3888 = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3889 result = DECL_TEMPLATE_RESULT (clone);
3890 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3891 DECL_TI_TEMPLATE (result) = clone;
3894 note_decl_for_pch (clone);
3899 /* Produce declarations for all appropriate clones of FN. If
3900 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
3901 CLASTYPE_METHOD_VEC as well. */
3904 clone_function_decl (tree fn, int update_method_vec_p)
3908 /* Avoid inappropriate cloning. */
3910 && DECL_CLONED_FUNCTION (TREE_CHAIN (fn)))
3913 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
3915 /* For each constructor, we need two variants: an in-charge version
3916 and a not-in-charge version. */
3917 clone = build_clone (fn, complete_ctor_identifier);
3918 if (update_method_vec_p)
3919 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3920 clone = build_clone (fn, base_ctor_identifier);
3921 if (update_method_vec_p)
3922 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3926 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
3928 /* For each destructor, we need three variants: an in-charge
3929 version, a not-in-charge version, and an in-charge deleting
3930 version. We clone the deleting version first because that
3931 means it will go second on the TYPE_METHODS list -- and that
3932 corresponds to the correct layout order in the virtual
3935 For a non-virtual destructor, we do not build a deleting
3937 if (DECL_VIRTUAL_P (fn))
3939 clone = build_clone (fn, deleting_dtor_identifier);
3940 if (update_method_vec_p)
3941 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3943 clone = build_clone (fn, complete_dtor_identifier);
3944 if (update_method_vec_p)
3945 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3946 clone = build_clone (fn, base_dtor_identifier);
3947 if (update_method_vec_p)
3948 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3951 /* Note that this is an abstract function that is never emitted. */
3952 DECL_ABSTRACT (fn) = 1;
3955 /* DECL is an in charge constructor, which is being defined. This will
3956 have had an in class declaration, from whence clones were
3957 declared. An out-of-class definition can specify additional default
3958 arguments. As it is the clones that are involved in overload
3959 resolution, we must propagate the information from the DECL to its
3963 adjust_clone_args (tree decl)
3967 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION (clone);
3968 clone = TREE_CHAIN (clone))
3970 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
3971 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
3972 tree decl_parms, clone_parms;
3974 clone_parms = orig_clone_parms;
3976 /* Skip the 'this' parameter. */
3977 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
3978 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3980 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
3981 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3982 if (DECL_HAS_VTT_PARM_P (decl))
3983 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3985 clone_parms = orig_clone_parms;
3986 if (DECL_HAS_VTT_PARM_P (clone))
3987 clone_parms = TREE_CHAIN (clone_parms);
3989 for (decl_parms = orig_decl_parms; decl_parms;
3990 decl_parms = TREE_CHAIN (decl_parms),
3991 clone_parms = TREE_CHAIN (clone_parms))
3993 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
3994 TREE_TYPE (clone_parms)));
3996 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
3998 /* A default parameter has been added. Adjust the
3999 clone's parameters. */
4000 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4001 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4004 clone_parms = orig_decl_parms;
4006 if (DECL_HAS_VTT_PARM_P (clone))
4008 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4009 TREE_VALUE (orig_clone_parms),
4011 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4013 type = build_method_type_directly (basetype,
4014 TREE_TYPE (TREE_TYPE (clone)),
4017 type = build_exception_variant (type, exceptions);
4018 TREE_TYPE (clone) = type;
4020 clone_parms = NULL_TREE;
4024 gcc_assert (!clone_parms);
4028 /* For each of the constructors and destructors in T, create an
4029 in-charge and not-in-charge variant. */
4032 clone_constructors_and_destructors (tree t)
4036 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4038 if (!CLASSTYPE_METHOD_VEC (t))
4041 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4042 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4043 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4044 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4047 /* Returns true iff class T has a user-defined constructor other than
4048 the default constructor. */
4051 type_has_user_nondefault_constructor (tree t)
4055 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4058 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4060 tree fn = OVL_CURRENT (fns);
4061 if (!DECL_ARTIFICIAL (fn)
4062 && (TREE_CODE (fn) == TEMPLATE_DECL
4063 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4071 /* Returns true iff FN is a user-provided function, i.e. user-declared
4072 and not defaulted at its first declaration. */
4075 user_provided_p (tree fn)
4077 if (TREE_CODE (fn) == TEMPLATE_DECL)
4080 return (!DECL_ARTIFICIAL (fn)
4081 && !(DECL_DEFAULTED_FN (fn)
4082 && DECL_INITIALIZED_IN_CLASS_P (fn)));
4085 /* Returns true iff class T has a user-provided constructor. */
4088 type_has_user_provided_constructor (tree t)
4092 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4095 /* This can happen in error cases; avoid crashing. */
4096 if (!CLASSTYPE_METHOD_VEC (t))
4099 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4100 if (user_provided_p (OVL_CURRENT (fns)))
4106 /* Returns true iff class T has a user-provided default constructor. */
4109 type_has_user_provided_default_constructor (tree t)
4113 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4116 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4118 tree fn = OVL_CURRENT (fns);
4119 if (TREE_CODE (fn) == FUNCTION_DECL
4120 && user_provided_p (fn))
4122 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4123 while (args && TREE_PURPOSE (args))
4124 args = TREE_CHAIN (args);
4125 if (!args || args == void_list_node)
4133 /* Returns true if FN can be explicitly defaulted. */
4136 defaultable_fn_p (tree fn)
4138 if (DECL_CONSTRUCTOR_P (fn))
4140 if (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4143 else if (copy_fn_p (fn) > 0)
4148 else if (DECL_DESTRUCTOR_P (fn))
4150 else if (DECL_ASSIGNMENT_OPERATOR_P (fn))
4151 return copy_fn_p (fn);
4156 /* Remove all zero-width bit-fields from T. */
4159 remove_zero_width_bit_fields (tree t)
4163 fieldsp = &TYPE_FIELDS (t);
4166 if (TREE_CODE (*fieldsp) == FIELD_DECL
4167 && DECL_C_BIT_FIELD (*fieldsp)
4168 && DECL_INITIAL (*fieldsp))
4169 *fieldsp = TREE_CHAIN (*fieldsp);
4171 fieldsp = &TREE_CHAIN (*fieldsp);
4175 /* Returns TRUE iff we need a cookie when dynamically allocating an
4176 array whose elements have the indicated class TYPE. */
4179 type_requires_array_cookie (tree type)
4182 bool has_two_argument_delete_p = false;
4184 gcc_assert (CLASS_TYPE_P (type));
4186 /* If there's a non-trivial destructor, we need a cookie. In order
4187 to iterate through the array calling the destructor for each
4188 element, we'll have to know how many elements there are. */
4189 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4192 /* If the usual deallocation function is a two-argument whose second
4193 argument is of type `size_t', then we have to pass the size of
4194 the array to the deallocation function, so we will need to store
4196 fns = lookup_fnfields (TYPE_BINFO (type),
4197 ansi_opname (VEC_DELETE_EXPR),
4199 /* If there are no `operator []' members, or the lookup is
4200 ambiguous, then we don't need a cookie. */
4201 if (!fns || fns == error_mark_node)
4203 /* Loop through all of the functions. */
4204 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4209 /* Select the current function. */
4210 fn = OVL_CURRENT (fns);
4211 /* See if this function is a one-argument delete function. If
4212 it is, then it will be the usual deallocation function. */
4213 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4214 if (second_parm == void_list_node)
4216 /* Do not consider this function if its second argument is an
4220 /* Otherwise, if we have a two-argument function and the second
4221 argument is `size_t', it will be the usual deallocation
4222 function -- unless there is one-argument function, too. */
4223 if (TREE_CHAIN (second_parm) == void_list_node
4224 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4225 has_two_argument_delete_p = true;
4228 return has_two_argument_delete_p;
4231 /* Check the validity of the bases and members declared in T. Add any
4232 implicitly-generated functions (like copy-constructors and
4233 assignment operators). Compute various flag bits (like
4234 CLASSTYPE_NON_POD_T) for T. This routine works purely at the C++
4235 level: i.e., independently of the ABI in use. */
4238 check_bases_and_members (tree t)
4240 /* Nonzero if the implicitly generated copy constructor should take
4241 a non-const reference argument. */
4242 int cant_have_const_ctor;
4243 /* Nonzero if the implicitly generated assignment operator
4244 should take a non-const reference argument. */
4245 int no_const_asn_ref;
4247 bool saved_complex_asn_ref;
4248 bool saved_nontrivial_dtor;
4250 /* By default, we use const reference arguments and generate default
4252 cant_have_const_ctor = 0;
4253 no_const_asn_ref = 0;
4255 /* Check all the base-classes. */
4256 check_bases (t, &cant_have_const_ctor,
4259 /* Check all the method declarations. */
4262 /* Save the initial values of these flags which only indicate whether
4263 or not the class has user-provided functions. As we analyze the
4264 bases and members we can set these flags for other reasons. */
4265 saved_complex_asn_ref = TYPE_HAS_COMPLEX_ASSIGN_REF (t);
4266 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4268 /* Check all the data member declarations. We cannot call
4269 check_field_decls until we have called check_bases check_methods,
4270 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4271 being set appropriately. */
4272 check_field_decls (t, &access_decls,
4273 &cant_have_const_ctor,
4276 /* A nearly-empty class has to be vptr-containing; a nearly empty
4277 class contains just a vptr. */
4278 if (!TYPE_CONTAINS_VPTR_P (t))
4279 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4281 /* Do some bookkeeping that will guide the generation of implicitly
4282 declared member functions. */
4283 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4284 /* We need to call a constructor for this class if it has a
4285 user-provided constructor, or if the default constructor is going
4286 to initialize the vptr. (This is not an if-and-only-if;
4287 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4288 themselves need constructing.) */
4289 TYPE_NEEDS_CONSTRUCTING (t)
4290 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4293 An aggregate is an array or a class with no user-provided
4294 constructors ... and no virtual functions.
4296 Again, other conditions for being an aggregate are checked
4298 CLASSTYPE_NON_AGGREGATE (t)
4299 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4300 CLASSTYPE_NON_POD_P (t)
4301 |= (CLASSTYPE_NON_AGGREGATE (t)
4302 || saved_nontrivial_dtor || saved_complex_asn_ref);
4303 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4304 TYPE_HAS_COMPLEX_DFLT (t)
4305 |= (TYPE_HAS_DEFAULT_CONSTRUCTOR (t) || TYPE_CONTAINS_VPTR_P (t));
4307 /* If the class has no user-declared constructor, but does have
4308 non-static const or reference data members that can never be
4309 initialized, issue a warning. */
4310 if (warn_uninitialized
4311 /* Classes with user-declared constructors are presumed to
4312 initialize these members. */
4313 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4314 /* Aggregates can be initialized with brace-enclosed
4316 && CLASSTYPE_NON_AGGREGATE (t))
4320 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4324 if (TREE_CODE (field) != FIELD_DECL)
4327 type = TREE_TYPE (field);
4328 if (TREE_CODE (type) == REFERENCE_TYPE)
4329 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4330 "in class without a constructor", field);
4331 else if (CP_TYPE_CONST_P (type)
4332 && (!CLASS_TYPE_P (type)
4333 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4334 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4335 "in class without a constructor", field);
4339 /* Synthesize any needed methods. */
4340 add_implicitly_declared_members (t,
4341 cant_have_const_ctor,
4344 /* Create the in-charge and not-in-charge variants of constructors
4346 clone_constructors_and_destructors (t);
4348 /* Process the using-declarations. */
4349 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4350 handle_using_decl (TREE_VALUE (access_decls), t);
4352 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4353 finish_struct_methods (t);
4355 /* Figure out whether or not we will need a cookie when dynamically
4356 allocating an array of this type. */
4357 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4358 = type_requires_array_cookie (t);
4361 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4362 accordingly. If a new vfield was created (because T doesn't have a
4363 primary base class), then the newly created field is returned. It
4364 is not added to the TYPE_FIELDS list; it is the caller's
4365 responsibility to do that. Accumulate declared virtual functions
4369 create_vtable_ptr (tree t, tree* virtuals_p)
4373 /* Collect the virtual functions declared in T. */
4374 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4375 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4376 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4378 tree new_virtual = make_node (TREE_LIST);
4380 BV_FN (new_virtual) = fn;
4381 BV_DELTA (new_virtual) = integer_zero_node;
4382 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4384 TREE_CHAIN (new_virtual) = *virtuals_p;
4385 *virtuals_p = new_virtual;
4388 /* If we couldn't find an appropriate base class, create a new field
4389 here. Even if there weren't any new virtual functions, we might need a
4390 new virtual function table if we're supposed to include vptrs in
4391 all classes that need them. */
4392 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4394 /* We build this decl with vtbl_ptr_type_node, which is a
4395 `vtable_entry_type*'. It might seem more precise to use
4396 `vtable_entry_type (*)[N]' where N is the number of virtual
4397 functions. However, that would require the vtable pointer in
4398 base classes to have a different type than the vtable pointer
4399 in derived classes. We could make that happen, but that
4400 still wouldn't solve all the problems. In particular, the
4401 type-based alias analysis code would decide that assignments
4402 to the base class vtable pointer can't alias assignments to
4403 the derived class vtable pointer, since they have different
4404 types. Thus, in a derived class destructor, where the base
4405 class constructor was inlined, we could generate bad code for
4406 setting up the vtable pointer.
4408 Therefore, we use one type for all vtable pointers. We still
4409 use a type-correct type; it's just doesn't indicate the array
4410 bounds. That's better than using `void*' or some such; it's
4411 cleaner, and it let's the alias analysis code know that these
4412 stores cannot alias stores to void*! */
4415 field = build_decl (FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4416 DECL_VIRTUAL_P (field) = 1;
4417 DECL_ARTIFICIAL (field) = 1;
4418 DECL_FIELD_CONTEXT (field) = t;
4419 DECL_FCONTEXT (field) = t;
4421 TYPE_VFIELD (t) = field;
4423 /* This class is non-empty. */
4424 CLASSTYPE_EMPTY_P (t) = 0;
4432 /* Fixup the inline function given by INFO now that the class is
4436 fixup_pending_inline (tree fn)
4438 if (DECL_PENDING_INLINE_INFO (fn))
4440 tree args = DECL_ARGUMENTS (fn);
4443 DECL_CONTEXT (args) = fn;
4444 args = TREE_CHAIN (args);
4449 /* Fixup the inline methods and friends in TYPE now that TYPE is
4453 fixup_inline_methods (tree type)
4455 tree method = TYPE_METHODS (type);
4456 VEC(tree,gc) *friends;
4459 if (method && TREE_CODE (method) == TREE_VEC)
4461 if (TREE_VEC_ELT (method, 1))
4462 method = TREE_VEC_ELT (method, 1);
4463 else if (TREE_VEC_ELT (method, 0))
4464 method = TREE_VEC_ELT (method, 0);
4466 method = TREE_VEC_ELT (method, 2);
4469 /* Do inline member functions. */
4470 for (; method; method = TREE_CHAIN (method))
4471 fixup_pending_inline (method);
4474 for (friends = CLASSTYPE_INLINE_FRIENDS (type), ix = 0;
4475 VEC_iterate (tree, friends, ix, method); ix++)
4476 fixup_pending_inline (method);
4477 CLASSTYPE_INLINE_FRIENDS (type) = NULL;
4480 /* Add OFFSET to all base types of BINFO which is a base in the
4481 hierarchy dominated by T.
4483 OFFSET, which is a type offset, is number of bytes. */
4486 propagate_binfo_offsets (tree binfo, tree offset)
4492 /* Update BINFO's offset. */
4493 BINFO_OFFSET (binfo)
4494 = convert (sizetype,
4495 size_binop (PLUS_EXPR,
4496 convert (ssizetype, BINFO_OFFSET (binfo)),
4499 /* Find the primary base class. */
4500 primary_binfo = get_primary_binfo (binfo);
4502 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4503 propagate_binfo_offsets (primary_binfo, offset);
4505 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4507 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4509 /* Don't do the primary base twice. */
4510 if (base_binfo == primary_binfo)
4513 if (BINFO_VIRTUAL_P (base_binfo))
4516 propagate_binfo_offsets (base_binfo, offset);
4520 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4521 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4522 empty subobjects of T. */
4525 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4529 bool first_vbase = true;
4532 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4535 if (!abi_version_at_least(2))
4537 /* In G++ 3.2, we incorrectly rounded the size before laying out
4538 the virtual bases. */
4539 finish_record_layout (rli, /*free_p=*/false);
4540 #ifdef STRUCTURE_SIZE_BOUNDARY
4541 /* Packed structures don't need to have minimum size. */
4542 if (! TYPE_PACKED (t))
4543 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4545 rli->offset = TYPE_SIZE_UNIT (t);
4546 rli->bitpos = bitsize_zero_node;
4547 rli->record_align = TYPE_ALIGN (t);
4550 /* Find the last field. The artificial fields created for virtual
4551 bases will go after the last extant field to date. */
4552 next_field = &TYPE_FIELDS (t);
4554 next_field = &TREE_CHAIN (*next_field);
4556 /* Go through the virtual bases, allocating space for each virtual
4557 base that is not already a primary base class. These are
4558 allocated in inheritance graph order. */
4559 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4561 if (!BINFO_VIRTUAL_P (vbase))
4564 if (!BINFO_PRIMARY_P (vbase))
4566 tree basetype = TREE_TYPE (vbase);
4568 /* This virtual base is not a primary base of any class in the
4569 hierarchy, so we have to add space for it. */
4570 next_field = build_base_field (rli, vbase,
4571 offsets, next_field);
4573 /* If the first virtual base might have been placed at a
4574 lower address, had we started from CLASSTYPE_SIZE, rather
4575 than TYPE_SIZE, issue a warning. There can be both false
4576 positives and false negatives from this warning in rare
4577 cases; to deal with all the possibilities would probably
4578 require performing both layout algorithms and comparing
4579 the results which is not particularly tractable. */
4583 (size_binop (CEIL_DIV_EXPR,
4584 round_up (CLASSTYPE_SIZE (t),
4585 CLASSTYPE_ALIGN (basetype)),
4587 BINFO_OFFSET (vbase))))
4589 "offset of virtual base %qT is not ABI-compliant and "
4590 "may change in a future version of GCC",
4593 first_vbase = false;
4598 /* Returns the offset of the byte just past the end of the base class
4602 end_of_base (tree binfo)
4606 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
4607 size = TYPE_SIZE_UNIT (char_type_node);
4608 else if (is_empty_class (BINFO_TYPE (binfo)))
4609 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4610 allocate some space for it. It cannot have virtual bases, so
4611 TYPE_SIZE_UNIT is fine. */
4612 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4614 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4616 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4619 /* Returns the offset of the byte just past the end of the base class
4620 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4621 only non-virtual bases are included. */
4624 end_of_class (tree t, int include_virtuals_p)
4626 tree result = size_zero_node;
4627 VEC(tree,gc) *vbases;
4633 for (binfo = TYPE_BINFO (t), i = 0;
4634 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4636 if (!include_virtuals_p
4637 && BINFO_VIRTUAL_P (base_binfo)
4638 && (!BINFO_PRIMARY_P (base_binfo)
4639 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4642 offset = end_of_base (base_binfo);
4643 if (INT_CST_LT_UNSIGNED (result, offset))
4647 /* G++ 3.2 did not check indirect virtual bases. */
4648 if (abi_version_at_least (2) && include_virtuals_p)
4649 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4650 VEC_iterate (tree, vbases, i, base_binfo); i++)
4652 offset = end_of_base (base_binfo);
4653 if (INT_CST_LT_UNSIGNED (result, offset))
4660 /* Warn about bases of T that are inaccessible because they are
4661 ambiguous. For example:
4664 struct T : public S {};
4665 struct U : public S, public T {};
4667 Here, `(S*) new U' is not allowed because there are two `S'
4671 warn_about_ambiguous_bases (tree t)
4674 VEC(tree,gc) *vbases;
4679 /* If there are no repeated bases, nothing can be ambiguous. */
4680 if (!CLASSTYPE_REPEATED_BASE_P (t))
4683 /* Check direct bases. */
4684 for (binfo = TYPE_BINFO (t), i = 0;
4685 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4687 basetype = BINFO_TYPE (base_binfo);
4689 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4690 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4694 /* Check for ambiguous virtual bases. */
4696 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4697 VEC_iterate (tree, vbases, i, binfo); i++)
4699 basetype = BINFO_TYPE (binfo);
4701 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4702 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4707 /* Compare two INTEGER_CSTs K1 and K2. */
4710 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4712 return tree_int_cst_compare ((tree) k1, (tree) k2);
4715 /* Increase the size indicated in RLI to account for empty classes
4716 that are "off the end" of the class. */
4719 include_empty_classes (record_layout_info rli)
4724 /* It might be the case that we grew the class to allocate a
4725 zero-sized base class. That won't be reflected in RLI, yet,
4726 because we are willing to overlay multiple bases at the same
4727 offset. However, now we need to make sure that RLI is big enough
4728 to reflect the entire class. */
4729 eoc = end_of_class (rli->t,
4730 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4731 rli_size = rli_size_unit_so_far (rli);
4732 if (TREE_CODE (rli_size) == INTEGER_CST
4733 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4735 if (!abi_version_at_least (2))
4736 /* In version 1 of the ABI, the size of a class that ends with
4737 a bitfield was not rounded up to a whole multiple of a
4738 byte. Because rli_size_unit_so_far returns only the number
4739 of fully allocated bytes, any extra bits were not included
4741 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4743 /* The size should have been rounded to a whole byte. */
4744 gcc_assert (tree_int_cst_equal
4745 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4747 = size_binop (PLUS_EXPR,
4749 size_binop (MULT_EXPR,
4750 convert (bitsizetype,
4751 size_binop (MINUS_EXPR,
4753 bitsize_int (BITS_PER_UNIT)));
4754 normalize_rli (rli);
4758 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4759 BINFO_OFFSETs for all of the base-classes. Position the vtable
4760 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4763 layout_class_type (tree t, tree *virtuals_p)
4765 tree non_static_data_members;
4768 record_layout_info rli;
4769 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4770 types that appear at that offset. */
4771 splay_tree empty_base_offsets;
4772 /* True if the last field layed out was a bit-field. */
4773 bool last_field_was_bitfield = false;
4774 /* The location at which the next field should be inserted. */
4776 /* T, as a base class. */
4779 /* Keep track of the first non-static data member. */
4780 non_static_data_members = TYPE_FIELDS (t);
4782 /* Start laying out the record. */
4783 rli = start_record_layout (t);
4785 /* Mark all the primary bases in the hierarchy. */
4786 determine_primary_bases (t);
4788 /* Create a pointer to our virtual function table. */
4789 vptr = create_vtable_ptr (t, virtuals_p);
4791 /* The vptr is always the first thing in the class. */
4794 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4795 TYPE_FIELDS (t) = vptr;
4796 next_field = &TREE_CHAIN (vptr);
4797 place_field (rli, vptr);
4800 next_field = &TYPE_FIELDS (t);
4802 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4803 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4805 build_base_fields (rli, empty_base_offsets, next_field);
4807 /* Layout the non-static data members. */
4808 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4813 /* We still pass things that aren't non-static data members to
4814 the back end, in case it wants to do something with them. */
4815 if (TREE_CODE (field) != FIELD_DECL)
4817 place_field (rli, field);
4818 /* If the static data member has incomplete type, keep track
4819 of it so that it can be completed later. (The handling
4820 of pending statics in finish_record_layout is
4821 insufficient; consider:
4824 struct S2 { static S1 s1; };
4826 At this point, finish_record_layout will be called, but
4827 S1 is still incomplete.) */
4828 if (TREE_CODE (field) == VAR_DECL)
4830 maybe_register_incomplete_var (field);
4831 /* The visibility of static data members is determined
4832 at their point of declaration, not their point of
4834 determine_visibility (field);
4839 type = TREE_TYPE (field);
4840 if (type == error_mark_node)
4843 padding = NULL_TREE;
4845 /* If this field is a bit-field whose width is greater than its
4846 type, then there are some special rules for allocating
4848 if (DECL_C_BIT_FIELD (field)
4849 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4851 integer_type_kind itk;
4853 bool was_unnamed_p = false;
4854 /* We must allocate the bits as if suitably aligned for the
4855 longest integer type that fits in this many bits. type
4856 of the field. Then, we are supposed to use the left over
4857 bits as additional padding. */
4858 for (itk = itk_char; itk != itk_none; ++itk)
4859 if (INT_CST_LT (DECL_SIZE (field),
4860 TYPE_SIZE (integer_types[itk])))
4863 /* ITK now indicates a type that is too large for the
4864 field. We have to back up by one to find the largest
4866 integer_type = integer_types[itk - 1];
4868 /* Figure out how much additional padding is required. GCC
4869 3.2 always created a padding field, even if it had zero
4871 if (!abi_version_at_least (2)
4872 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4874 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4875 /* In a union, the padding field must have the full width
4876 of the bit-field; all fields start at offset zero. */
4877 padding = DECL_SIZE (field);
4880 if (TREE_CODE (t) == UNION_TYPE)
4881 warning (OPT_Wabi, "size assigned to %qT may not be "
4882 "ABI-compliant and may change in a future "
4885 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4886 TYPE_SIZE (integer_type));
4889 #ifdef PCC_BITFIELD_TYPE_MATTERS
4890 /* An unnamed bitfield does not normally affect the
4891 alignment of the containing class on a target where
4892 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4893 make any exceptions for unnamed bitfields when the
4894 bitfields are longer than their types. Therefore, we
4895 temporarily give the field a name. */
4896 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4898 was_unnamed_p = true;
4899 DECL_NAME (field) = make_anon_name ();
4902 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4903 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4904 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4905 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4906 empty_base_offsets);
4908 DECL_NAME (field) = NULL_TREE;
4909 /* Now that layout has been performed, set the size of the
4910 field to the size of its declared type; the rest of the
4911 field is effectively invisible. */
4912 DECL_SIZE (field) = TYPE_SIZE (type);
4913 /* We must also reset the DECL_MODE of the field. */
4914 if (abi_version_at_least (2))
4915 DECL_MODE (field) = TYPE_MODE (type);
4917 && DECL_MODE (field) != TYPE_MODE (type))
4918 /* Versions of G++ before G++ 3.4 did not reset the
4921 "the offset of %qD may not be ABI-compliant and may "
4922 "change in a future version of GCC", field);
4925 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4926 empty_base_offsets);
4928 /* Remember the location of any empty classes in FIELD. */
4929 if (abi_version_at_least (2))
4930 record_subobject_offsets (TREE_TYPE (field),
4931 byte_position(field),
4933 /*is_data_member=*/true);
4935 /* If a bit-field does not immediately follow another bit-field,
4936 and yet it starts in the middle of a byte, we have failed to
4937 comply with the ABI. */
4939 && DECL_C_BIT_FIELD (field)
4940 /* The TREE_NO_WARNING flag gets set by Objective-C when
4941 laying out an Objective-C class. The ObjC ABI differs
4942 from the C++ ABI, and so we do not want a warning
4944 && !TREE_NO_WARNING (field)
4945 && !last_field_was_bitfield
4946 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
4947 DECL_FIELD_BIT_OFFSET (field),
4948 bitsize_unit_node)))
4949 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
4950 "change in a future version of GCC", field);
4952 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
4953 offset of the field. */
4955 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
4956 byte_position (field))
4957 && contains_empty_class_p (TREE_TYPE (field)))
4958 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
4959 "classes to be placed at different locations in a "
4960 "future version of GCC", field);
4962 /* The middle end uses the type of expressions to determine the
4963 possible range of expression values. In order to optimize
4964 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
4965 must be made aware of the width of "i", via its type.
4967 Because C++ does not have integer types of arbitrary width,
4968 we must (for the purposes of the front end) convert from the
4969 type assigned here to the declared type of the bitfield
4970 whenever a bitfield expression is used as an rvalue.
4971 Similarly, when assigning a value to a bitfield, the value
4972 must be converted to the type given the bitfield here. */
4973 if (DECL_C_BIT_FIELD (field))
4975 unsigned HOST_WIDE_INT width;
4976 tree ftype = TREE_TYPE (field);
4977 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
4978 if (width != TYPE_PRECISION (ftype))
4981 = c_build_bitfield_integer_type (width,
4982 TYPE_UNSIGNED (ftype));
4984 = cp_build_qualified_type (TREE_TYPE (field),
4985 TYPE_QUALS (ftype));
4989 /* If we needed additional padding after this field, add it
4995 padding_field = build_decl (FIELD_DECL,
4998 DECL_BIT_FIELD (padding_field) = 1;
4999 DECL_SIZE (padding_field) = padding;
5000 DECL_CONTEXT (padding_field) = t;
5001 DECL_ARTIFICIAL (padding_field) = 1;
5002 DECL_IGNORED_P (padding_field) = 1;
5003 layout_nonempty_base_or_field (rli, padding_field,
5005 empty_base_offsets);
5008 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5011 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5013 /* Make sure that we are on a byte boundary so that the size of
5014 the class without virtual bases will always be a round number
5016 rli->bitpos = round_up (rli->bitpos, BITS_PER_UNIT);
5017 normalize_rli (rli);
5020 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5022 if (!abi_version_at_least (2))
5023 include_empty_classes(rli);
5025 /* Delete all zero-width bit-fields from the list of fields. Now
5026 that the type is laid out they are no longer important. */
5027 remove_zero_width_bit_fields (t);
5029 /* Create the version of T used for virtual bases. We do not use
5030 make_class_type for this version; this is an artificial type. For
5031 a POD type, we just reuse T. */
5032 if (CLASSTYPE_NON_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5034 base_t = make_node (TREE_CODE (t));
5036 /* Set the size and alignment for the new type. In G++ 3.2, all
5037 empty classes were considered to have size zero when used as
5039 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5041 TYPE_SIZE (base_t) = bitsize_zero_node;
5042 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5043 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5045 "layout of classes derived from empty class %qT "
5046 "may change in a future version of GCC",
5053 /* If the ABI version is not at least two, and the last
5054 field was a bit-field, RLI may not be on a byte
5055 boundary. In particular, rli_size_unit_so_far might
5056 indicate the last complete byte, while rli_size_so_far
5057 indicates the total number of bits used. Therefore,
5058 rli_size_so_far, rather than rli_size_unit_so_far, is
5059 used to compute TYPE_SIZE_UNIT. */
5060 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5061 TYPE_SIZE_UNIT (base_t)
5062 = size_binop (MAX_EXPR,
5064 size_binop (CEIL_DIV_EXPR,
5065 rli_size_so_far (rli),
5066 bitsize_int (BITS_PER_UNIT))),
5069 = size_binop (MAX_EXPR,
5070 rli_size_so_far (rli),
5071 size_binop (MULT_EXPR,
5072 convert (bitsizetype, eoc),
5073 bitsize_int (BITS_PER_UNIT)));
5075 TYPE_ALIGN (base_t) = rli->record_align;
5076 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5078 /* Copy the fields from T. */
5079 next_field = &TYPE_FIELDS (base_t);
5080 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5081 if (TREE_CODE (field) == FIELD_DECL)
5083 *next_field = build_decl (FIELD_DECL,
5086 DECL_CONTEXT (*next_field) = base_t;
5087 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5088 DECL_FIELD_BIT_OFFSET (*next_field)
5089 = DECL_FIELD_BIT_OFFSET (field);
5090 DECL_SIZE (*next_field) = DECL_SIZE (field);
5091 DECL_MODE (*next_field) = DECL_MODE (field);
5092 next_field = &TREE_CHAIN (*next_field);
5095 /* Record the base version of the type. */
5096 CLASSTYPE_AS_BASE (t) = base_t;
5097 TYPE_CONTEXT (base_t) = t;
5100 CLASSTYPE_AS_BASE (t) = t;
5102 /* Every empty class contains an empty class. */
5103 if (CLASSTYPE_EMPTY_P (t))
5104 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5106 /* Set the TYPE_DECL for this type to contain the right
5107 value for DECL_OFFSET, so that we can use it as part
5108 of a COMPONENT_REF for multiple inheritance. */
5109 layout_decl (TYPE_MAIN_DECL (t), 0);
5111 /* Now fix up any virtual base class types that we left lying
5112 around. We must get these done before we try to lay out the
5113 virtual function table. As a side-effect, this will remove the
5114 base subobject fields. */
5115 layout_virtual_bases (rli, empty_base_offsets);
5117 /* Make sure that empty classes are reflected in RLI at this
5119 include_empty_classes(rli);
5121 /* Make sure not to create any structures with zero size. */
5122 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5124 build_decl (FIELD_DECL, NULL_TREE, char_type_node));
5126 /* Let the back end lay out the type. */
5127 finish_record_layout (rli, /*free_p=*/true);
5129 /* Warn about bases that can't be talked about due to ambiguity. */
5130 warn_about_ambiguous_bases (t);
5132 /* Now that we're done with layout, give the base fields the real types. */
5133 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5134 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5135 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5138 splay_tree_delete (empty_base_offsets);
5140 if (CLASSTYPE_EMPTY_P (t)
5141 && tree_int_cst_lt (sizeof_biggest_empty_class,
5142 TYPE_SIZE_UNIT (t)))
5143 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5146 /* Determine the "key method" for the class type indicated by TYPE,
5147 and set CLASSTYPE_KEY_METHOD accordingly. */
5150 determine_key_method (tree type)
5154 if (TYPE_FOR_JAVA (type)
5155 || processing_template_decl
5156 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5157 || CLASSTYPE_INTERFACE_KNOWN (type))
5160 /* The key method is the first non-pure virtual function that is not
5161 inline at the point of class definition. On some targets the
5162 key function may not be inline; those targets should not call
5163 this function until the end of the translation unit. */
5164 for (method = TYPE_METHODS (type); method != NULL_TREE;
5165 method = TREE_CHAIN (method))
5166 if (DECL_VINDEX (method) != NULL_TREE
5167 && ! DECL_DECLARED_INLINE_P (method)
5168 && ! DECL_PURE_VIRTUAL_P (method))
5170 CLASSTYPE_KEY_METHOD (type) = method;
5177 /* Perform processing required when the definition of T (a class type)
5181 finish_struct_1 (tree t)
5184 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5185 tree virtuals = NULL_TREE;
5188 if (COMPLETE_TYPE_P (t))
5190 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5191 error ("redefinition of %q#T", t);
5196 /* If this type was previously laid out as a forward reference,
5197 make sure we lay it out again. */
5198 TYPE_SIZE (t) = NULL_TREE;
5199 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5201 fixup_inline_methods (t);
5203 /* Make assumptions about the class; we'll reset the flags if
5205 CLASSTYPE_EMPTY_P (t) = 1;
5206 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5207 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5209 /* Do end-of-class semantic processing: checking the validity of the
5210 bases and members and add implicitly generated methods. */
5211 check_bases_and_members (t);
5213 /* Find the key method. */
5214 if (TYPE_CONTAINS_VPTR_P (t))
5216 /* The Itanium C++ ABI permits the key method to be chosen when
5217 the class is defined -- even though the key method so
5218 selected may later turn out to be an inline function. On
5219 some systems (such as ARM Symbian OS) the key method cannot
5220 be determined until the end of the translation unit. On such
5221 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5222 will cause the class to be added to KEYED_CLASSES. Then, in
5223 finish_file we will determine the key method. */
5224 if (targetm.cxx.key_method_may_be_inline ())
5225 determine_key_method (t);
5227 /* If a polymorphic class has no key method, we may emit the vtable
5228 in every translation unit where the class definition appears. */
5229 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5230 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5233 /* Layout the class itself. */
5234 layout_class_type (t, &virtuals);
5235 if (CLASSTYPE_AS_BASE (t) != t)
5236 /* We use the base type for trivial assignments, and hence it
5238 compute_record_mode (CLASSTYPE_AS_BASE (t));
5240 virtuals = modify_all_vtables (t, nreverse (virtuals));
5242 /* If necessary, create the primary vtable for this class. */
5243 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5245 /* We must enter these virtuals into the table. */
5246 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5247 build_primary_vtable (NULL_TREE, t);
5248 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5249 /* Here we know enough to change the type of our virtual
5250 function table, but we will wait until later this function. */
5251 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5254 if (TYPE_CONTAINS_VPTR_P (t))
5259 if (BINFO_VTABLE (TYPE_BINFO (t)))
5260 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5261 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5262 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5264 /* Add entries for virtual functions introduced by this class. */
5265 BINFO_VIRTUALS (TYPE_BINFO (t))
5266 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5268 /* Set DECL_VINDEX for all functions declared in this class. */
5269 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5271 fn = TREE_CHAIN (fn),
5272 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5273 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5275 tree fndecl = BV_FN (fn);
5277 if (DECL_THUNK_P (fndecl))
5278 /* A thunk. We should never be calling this entry directly
5279 from this vtable -- we'd use the entry for the non
5280 thunk base function. */
5281 DECL_VINDEX (fndecl) = NULL_TREE;
5282 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5283 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5287 finish_struct_bits (t);
5289 /* Complete the rtl for any static member objects of the type we're
5291 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5292 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5293 && TREE_TYPE (x) != error_mark_node
5294 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5295 DECL_MODE (x) = TYPE_MODE (t);
5297 /* Done with FIELDS...now decide whether to sort these for
5298 faster lookups later.
5300 We use a small number because most searches fail (succeeding
5301 ultimately as the search bores through the inheritance
5302 hierarchy), and we want this failure to occur quickly. */
5304 n_fields = count_fields (TYPE_FIELDS (t));
5307 struct sorted_fields_type *field_vec = GGC_NEWVAR
5308 (struct sorted_fields_type,
5309 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5310 field_vec->len = n_fields;
5311 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5312 qsort (field_vec->elts, n_fields, sizeof (tree),
5314 if (! DECL_LANG_SPECIFIC (TYPE_MAIN_DECL (t)))
5315 retrofit_lang_decl (TYPE_MAIN_DECL (t));
5316 DECL_SORTED_FIELDS (TYPE_MAIN_DECL (t)) = field_vec;
5319 /* Complain if one of the field types requires lower visibility. */
5320 constrain_class_visibility (t);
5322 /* Make the rtl for any new vtables we have created, and unmark
5323 the base types we marked. */
5326 /* Build the VTT for T. */
5329 /* This warning does not make sense for Java classes, since they
5330 cannot have destructors. */
5331 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5335 dtor = CLASSTYPE_DESTRUCTORS (t);
5336 if (/* An implicitly declared destructor is always public. And,
5337 if it were virtual, we would have created it by now. */
5339 || (!DECL_VINDEX (dtor)
5340 && (/* public non-virtual */
5341 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5342 || (/* non-public non-virtual with friends */
5343 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5344 && (CLASSTYPE_FRIEND_CLASSES (t)
5345 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5346 warning (OPT_Wnon_virtual_dtor,
5347 "%q#T has virtual functions and accessible"
5348 " non-virtual destructor", t);
5353 if (warn_overloaded_virtual)
5356 /* Class layout, assignment of virtual table slots, etc., is now
5357 complete. Give the back end a chance to tweak the visibility of
5358 the class or perform any other required target modifications. */
5359 targetm.cxx.adjust_class_at_definition (t);
5361 maybe_suppress_debug_info (t);
5363 dump_class_hierarchy (t);
5365 /* Finish debugging output for this type. */
5366 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5369 /* When T was built up, the member declarations were added in reverse
5370 order. Rearrange them to declaration order. */
5373 unreverse_member_declarations (tree t)
5379 /* The following lists are all in reverse order. Put them in
5380 declaration order now. */
5381 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5382 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5384 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5385 reverse order, so we can't just use nreverse. */
5387 for (x = TYPE_FIELDS (t);
5388 x && TREE_CODE (x) != TYPE_DECL;
5391 next = TREE_CHAIN (x);
5392 TREE_CHAIN (x) = prev;
5397 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5399 TYPE_FIELDS (t) = prev;
5404 finish_struct (tree t, tree attributes)
5406 location_t saved_loc = input_location;
5408 /* Now that we've got all the field declarations, reverse everything
5410 unreverse_member_declarations (t);
5412 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5414 /* Nadger the current location so that diagnostics point to the start of
5415 the struct, not the end. */
5416 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5418 if (processing_template_decl)
5422 finish_struct_methods (t);
5423 TYPE_SIZE (t) = bitsize_zero_node;
5424 TYPE_SIZE_UNIT (t) = size_zero_node;
5426 /* We need to emit an error message if this type was used as a parameter
5427 and it is an abstract type, even if it is a template. We construct
5428 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5429 account and we call complete_vars with this type, which will check
5430 the PARM_DECLS. Note that while the type is being defined,
5431 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5432 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5433 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5434 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5435 if (DECL_PURE_VIRTUAL_P (x))
5436 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5440 finish_struct_1 (t);
5442 input_location = saved_loc;
5444 TYPE_BEING_DEFINED (t) = 0;
5446 if (current_class_type)
5449 error ("trying to finish struct, but kicked out due to previous parse errors");
5451 if (processing_template_decl && at_function_scope_p ())
5452 add_stmt (build_min (TAG_DEFN, t));
5457 /* Return the dynamic type of INSTANCE, if known.
5458 Used to determine whether the virtual function table is needed
5461 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5462 of our knowledge of its type. *NONNULL should be initialized
5463 before this function is called. */
5466 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5468 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5470 switch (TREE_CODE (instance))
5473 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5476 return RECUR (TREE_OPERAND (instance, 0));
5479 /* This is a call to a constructor, hence it's never zero. */
5480 if (TREE_HAS_CONSTRUCTOR (instance))
5484 return TREE_TYPE (instance);
5489 /* This is a call to a constructor, hence it's never zero. */
5490 if (TREE_HAS_CONSTRUCTOR (instance))
5494 return TREE_TYPE (instance);
5496 return RECUR (TREE_OPERAND (instance, 0));
5498 case POINTER_PLUS_EXPR:
5501 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5502 return RECUR (TREE_OPERAND (instance, 0));
5503 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5504 /* Propagate nonnull. */
5505 return RECUR (TREE_OPERAND (instance, 0));
5510 return RECUR (TREE_OPERAND (instance, 0));
5513 instance = TREE_OPERAND (instance, 0);
5516 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5517 with a real object -- given &p->f, p can still be null. */
5518 tree t = get_base_address (instance);
5519 /* ??? Probably should check DECL_WEAK here. */
5520 if (t && DECL_P (t))
5523 return RECUR (instance);
5526 /* If this component is really a base class reference, then the field
5527 itself isn't definitive. */
5528 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5529 return RECUR (TREE_OPERAND (instance, 0));
5530 return RECUR (TREE_OPERAND (instance, 1));
5534 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5535 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
5539 return TREE_TYPE (TREE_TYPE (instance));
5541 /* fall through... */
5545 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
5549 return TREE_TYPE (instance);
5551 else if (instance == current_class_ptr)
5556 /* if we're in a ctor or dtor, we know our type. */
5557 if (DECL_LANG_SPECIFIC (current_function_decl)
5558 && (DECL_CONSTRUCTOR_P (current_function_decl)
5559 || DECL_DESTRUCTOR_P (current_function_decl)))
5563 return TREE_TYPE (TREE_TYPE (instance));
5566 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5568 /* We only need one hash table because it is always left empty. */
5571 ht = htab_create (37,
5576 /* Reference variables should be references to objects. */
5580 /* Enter the INSTANCE in a table to prevent recursion; a
5581 variable's initializer may refer to the variable
5583 if (TREE_CODE (instance) == VAR_DECL
5584 && DECL_INITIAL (instance)
5585 && !htab_find (ht, instance))
5590 slot = htab_find_slot (ht, instance, INSERT);
5592 type = RECUR (DECL_INITIAL (instance));
5593 htab_remove_elt (ht, instance);
5606 /* Return nonzero if the dynamic type of INSTANCE is known, and
5607 equivalent to the static type. We also handle the case where
5608 INSTANCE is really a pointer. Return negative if this is a
5609 ctor/dtor. There the dynamic type is known, but this might not be
5610 the most derived base of the original object, and hence virtual
5611 bases may not be layed out according to this type.
5613 Used to determine whether the virtual function table is needed
5616 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5617 of our knowledge of its type. *NONNULL should be initialized
5618 before this function is called. */
5621 resolves_to_fixed_type_p (tree instance, int* nonnull)
5623 tree t = TREE_TYPE (instance);
5625 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5626 if (fixed == NULL_TREE)
5628 if (POINTER_TYPE_P (t))
5630 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5632 return cdtorp ? -1 : 1;
5637 init_class_processing (void)
5639 current_class_depth = 0;
5640 current_class_stack_size = 10;
5642 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5643 local_classes = VEC_alloc (tree, gc, 8);
5644 sizeof_biggest_empty_class = size_zero_node;
5646 ridpointers[(int) RID_PUBLIC] = access_public_node;
5647 ridpointers[(int) RID_PRIVATE] = access_private_node;
5648 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5651 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5654 restore_class_cache (void)
5658 /* We are re-entering the same class we just left, so we don't
5659 have to search the whole inheritance matrix to find all the
5660 decls to bind again. Instead, we install the cached
5661 class_shadowed list and walk through it binding names. */
5662 push_binding_level (previous_class_level);
5663 class_binding_level = previous_class_level;
5664 /* Restore IDENTIFIER_TYPE_VALUE. */
5665 for (type = class_binding_level->type_shadowed;
5667 type = TREE_CHAIN (type))
5668 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5671 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5672 appropriate for TYPE.
5674 So that we may avoid calls to lookup_name, we cache the _TYPE
5675 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5677 For multiple inheritance, we perform a two-pass depth-first search
5678 of the type lattice. */
5681 pushclass (tree type)
5683 class_stack_node_t csn;
5685 type = TYPE_MAIN_VARIANT (type);
5687 /* Make sure there is enough room for the new entry on the stack. */
5688 if (current_class_depth + 1 >= current_class_stack_size)
5690 current_class_stack_size *= 2;
5692 = XRESIZEVEC (struct class_stack_node, current_class_stack,
5693 current_class_stack_size);
5696 /* Insert a new entry on the class stack. */
5697 csn = current_class_stack + current_class_depth;
5698 csn->name = current_class_name;
5699 csn->type = current_class_type;
5700 csn->access = current_access_specifier;
5701 csn->names_used = 0;
5703 current_class_depth++;
5705 /* Now set up the new type. */
5706 current_class_name = TYPE_NAME (type);
5707 if (TREE_CODE (current_class_name) == TYPE_DECL)
5708 current_class_name = DECL_NAME (current_class_name);
5709 current_class_type = type;
5711 /* By default, things in classes are private, while things in
5712 structures or unions are public. */
5713 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5714 ? access_private_node
5715 : access_public_node);
5717 if (previous_class_level
5718 && type != previous_class_level->this_entity
5719 && current_class_depth == 1)
5721 /* Forcibly remove any old class remnants. */
5722 invalidate_class_lookup_cache ();
5725 if (!previous_class_level
5726 || type != previous_class_level->this_entity
5727 || current_class_depth > 1)
5730 restore_class_cache ();
5733 /* When we exit a toplevel class scope, we save its binding level so
5734 that we can restore it quickly. Here, we've entered some other
5735 class, so we must invalidate our cache. */
5738 invalidate_class_lookup_cache (void)
5740 previous_class_level = NULL;
5743 /* Get out of the current class scope. If we were in a class scope
5744 previously, that is the one popped to. */
5751 current_class_depth--;
5752 current_class_name = current_class_stack[current_class_depth].name;
5753 current_class_type = current_class_stack[current_class_depth].type;
5754 current_access_specifier = current_class_stack[current_class_depth].access;
5755 if (current_class_stack[current_class_depth].names_used)
5756 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5759 /* Mark the top of the class stack as hidden. */
5762 push_class_stack (void)
5764 if (current_class_depth)
5765 ++current_class_stack[current_class_depth - 1].hidden;
5768 /* Mark the top of the class stack as un-hidden. */
5771 pop_class_stack (void)
5773 if (current_class_depth)
5774 --current_class_stack[current_class_depth - 1].hidden;
5777 /* Returns 1 if the class type currently being defined is either T or
5778 a nested type of T. */
5781 currently_open_class (tree t)
5785 /* We start looking from 1 because entry 0 is from global scope,
5787 for (i = current_class_depth; i > 0; --i)
5790 if (i == current_class_depth)
5791 c = current_class_type;
5794 if (current_class_stack[i].hidden)
5796 c = current_class_stack[i].type;
5800 if (same_type_p (c, t))
5806 /* If either current_class_type or one of its enclosing classes are derived
5807 from T, return the appropriate type. Used to determine how we found
5808 something via unqualified lookup. */
5811 currently_open_derived_class (tree t)
5815 /* The bases of a dependent type are unknown. */
5816 if (dependent_type_p (t))
5819 if (!current_class_type)
5822 if (DERIVED_FROM_P (t, current_class_type))
5823 return current_class_type;
5825 for (i = current_class_depth - 1; i > 0; --i)
5827 if (current_class_stack[i].hidden)
5829 if (DERIVED_FROM_P (t, current_class_stack[i].type))
5830 return current_class_stack[i].type;
5836 /* When entering a class scope, all enclosing class scopes' names with
5837 static meaning (static variables, static functions, types and
5838 enumerators) have to be visible. This recursive function calls
5839 pushclass for all enclosing class contexts until global or a local
5840 scope is reached. TYPE is the enclosed class. */
5843 push_nested_class (tree type)
5845 /* A namespace might be passed in error cases, like A::B:C. */
5846 if (type == NULL_TREE
5847 || !CLASS_TYPE_P (type))
5850 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
5855 /* Undoes a push_nested_class call. */
5858 pop_nested_class (void)
5860 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5863 if (context && CLASS_TYPE_P (context))
5864 pop_nested_class ();
5867 /* Returns the number of extern "LANG" blocks we are nested within. */
5870 current_lang_depth (void)
5872 return VEC_length (tree, current_lang_base);
5875 /* Set global variables CURRENT_LANG_NAME to appropriate value
5876 so that behavior of name-mangling machinery is correct. */
5879 push_lang_context (tree name)
5881 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
5883 if (name == lang_name_cplusplus)
5885 current_lang_name = name;
5887 else if (name == lang_name_java)
5889 current_lang_name = name;
5890 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5891 (See record_builtin_java_type in decl.c.) However, that causes
5892 incorrect debug entries if these types are actually used.
5893 So we re-enable debug output after extern "Java". */
5894 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
5895 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
5896 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
5897 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
5898 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
5899 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
5900 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
5901 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
5903 else if (name == lang_name_c)
5905 current_lang_name = name;
5908 error ("language string %<\"%E\"%> not recognized", name);
5911 /* Get out of the current language scope. */
5914 pop_lang_context (void)
5916 current_lang_name = VEC_pop (tree, current_lang_base);
5919 /* Type instantiation routines. */
5921 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
5922 matches the TARGET_TYPE. If there is no satisfactory match, return
5923 error_mark_node, and issue an error & warning messages under
5924 control of FLAGS. Permit pointers to member function if FLAGS
5925 permits. If TEMPLATE_ONLY, the name of the overloaded function was
5926 a template-id, and EXPLICIT_TARGS are the explicitly provided
5927 template arguments. If OVERLOAD is for one or more member
5928 functions, then ACCESS_PATH is the base path used to reference
5929 those member functions. */
5932 resolve_address_of_overloaded_function (tree target_type,
5934 tsubst_flags_t flags,
5936 tree explicit_targs,
5939 /* Here's what the standard says:
5943 If the name is a function template, template argument deduction
5944 is done, and if the argument deduction succeeds, the deduced
5945 arguments are used to generate a single template function, which
5946 is added to the set of overloaded functions considered.
5948 Non-member functions and static member functions match targets of
5949 type "pointer-to-function" or "reference-to-function." Nonstatic
5950 member functions match targets of type "pointer-to-member
5951 function;" the function type of the pointer to member is used to
5952 select the member function from the set of overloaded member
5953 functions. If a nonstatic member function is selected, the
5954 reference to the overloaded function name is required to have the
5955 form of a pointer to member as described in 5.3.1.
5957 If more than one function is selected, any template functions in
5958 the set are eliminated if the set also contains a non-template
5959 function, and any given template function is eliminated if the
5960 set contains a second template function that is more specialized
5961 than the first according to the partial ordering rules 14.5.5.2.
5962 After such eliminations, if any, there shall remain exactly one
5963 selected function. */
5966 int is_reference = 0;
5967 /* We store the matches in a TREE_LIST rooted here. The functions
5968 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
5969 interoperability with most_specialized_instantiation. */
5970 tree matches = NULL_TREE;
5973 /* By the time we get here, we should be seeing only real
5974 pointer-to-member types, not the internal POINTER_TYPE to
5975 METHOD_TYPE representation. */
5976 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
5977 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
5979 gcc_assert (is_overloaded_fn (overload));
5981 /* Check that the TARGET_TYPE is reasonable. */
5982 if (TYPE_PTRFN_P (target_type))
5984 else if (TYPE_PTRMEMFUNC_P (target_type))
5985 /* This is OK, too. */
5987 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
5989 /* This is OK, too. This comes from a conversion to reference
5991 target_type = build_reference_type (target_type);
5996 if (flags & tf_error)
5997 error ("cannot resolve overloaded function %qD based on"
5998 " conversion to type %qT",
5999 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6000 return error_mark_node;
6003 /* If we can find a non-template function that matches, we can just
6004 use it. There's no point in generating template instantiations
6005 if we're just going to throw them out anyhow. But, of course, we
6006 can only do this when we don't *need* a template function. */
6011 for (fns = overload; fns; fns = OVL_NEXT (fns))
6013 tree fn = OVL_CURRENT (fns);
6016 if (TREE_CODE (fn) == TEMPLATE_DECL)
6017 /* We're not looking for templates just yet. */
6020 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6022 /* We're looking for a non-static member, and this isn't
6023 one, or vice versa. */
6026 /* Ignore functions which haven't been explicitly
6028 if (DECL_ANTICIPATED (fn))
6031 /* See if there's a match. */
6032 fntype = TREE_TYPE (fn);
6034 fntype = build_ptrmemfunc_type (build_pointer_type (fntype));
6035 else if (!is_reference)
6036 fntype = build_pointer_type (fntype);
6038 if (can_convert_arg (target_type, fntype, fn, LOOKUP_NORMAL))
6039 matches = tree_cons (fn, NULL_TREE, matches);
6043 /* Now, if we've already got a match (or matches), there's no need
6044 to proceed to the template functions. But, if we don't have a
6045 match we need to look at them, too. */
6048 tree target_fn_type;
6049 tree target_arg_types;
6050 tree target_ret_type;
6055 = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (target_type));
6057 target_fn_type = TREE_TYPE (target_type);
6058 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6059 target_ret_type = TREE_TYPE (target_fn_type);
6061 /* Never do unification on the 'this' parameter. */
6062 if (TREE_CODE (target_fn_type) == METHOD_TYPE)
6063 target_arg_types = TREE_CHAIN (target_arg_types);
6065 for (fns = overload; fns; fns = OVL_NEXT (fns))
6067 tree fn = OVL_CURRENT (fns);
6069 tree instantiation_type;
6072 if (TREE_CODE (fn) != TEMPLATE_DECL)
6073 /* We're only looking for templates. */
6076 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6078 /* We're not looking for a non-static member, and this is
6079 one, or vice versa. */
6082 /* Try to do argument deduction. */
6083 targs = make_tree_vec (DECL_NTPARMS (fn));
6084 if (fn_type_unification (fn, explicit_targs, targs,
6085 target_arg_types, target_ret_type,
6086 DEDUCE_EXACT, LOOKUP_NORMAL))
6087 /* Argument deduction failed. */
6090 /* Instantiate the template. */
6091 instantiation = instantiate_template (fn, targs, flags);
6092 if (instantiation == error_mark_node)
6093 /* Instantiation failed. */
6096 /* See if there's a match. */
6097 instantiation_type = TREE_TYPE (instantiation);
6099 instantiation_type =
6100 build_ptrmemfunc_type (build_pointer_type (instantiation_type));
6101 else if (!is_reference)
6102 instantiation_type = build_pointer_type (instantiation_type);
6103 if (can_convert_arg (target_type, instantiation_type, instantiation,
6105 matches = tree_cons (instantiation, fn, matches);
6108 /* Now, remove all but the most specialized of the matches. */
6111 tree match = most_specialized_instantiation (matches);
6113 if (match != error_mark_node)
6114 matches = tree_cons (TREE_PURPOSE (match),
6120 /* Now we should have exactly one function in MATCHES. */
6121 if (matches == NULL_TREE)
6123 /* There were *no* matches. */
6124 if (flags & tf_error)
6126 error ("no matches converting function %qD to type %q#T",
6127 DECL_NAME (OVL_FUNCTION (overload)),
6130 /* print_candidates expects a chain with the functions in
6131 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6132 so why be clever?). */
6133 for (; overload; overload = OVL_NEXT (overload))
6134 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
6137 print_candidates (matches);
6139 return error_mark_node;
6141 else if (TREE_CHAIN (matches))
6143 /* There were too many matches. */
6145 if (flags & tf_error)
6149 error ("converting overloaded function %qD to type %q#T is ambiguous",
6150 DECL_NAME (OVL_FUNCTION (overload)),
6153 /* Since print_candidates expects the functions in the
6154 TREE_VALUE slot, we flip them here. */
6155 for (match = matches; match; match = TREE_CHAIN (match))
6156 TREE_VALUE (match) = TREE_PURPOSE (match);
6158 print_candidates (matches);
6161 return error_mark_node;
6164 /* Good, exactly one match. Now, convert it to the correct type. */
6165 fn = TREE_PURPOSE (matches);
6167 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6168 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6170 static int explained;
6172 if (!(flags & tf_error))
6173 return error_mark_node;
6175 permerror (input_location, "assuming pointer to member %qD", fn);
6178 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6183 /* If we're doing overload resolution purely for the purpose of
6184 determining conversion sequences, we should not consider the
6185 function used. If this conversion sequence is selected, the
6186 function will be marked as used at this point. */
6187 if (!(flags & tf_conv))
6189 /* Make =delete work with SFINAE. */
6190 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6191 return error_mark_node;
6194 /* We could not check access when this expression was originally
6195 created since we did not know at that time to which function
6196 the expression referred. */
6197 if (DECL_FUNCTION_MEMBER_P (fn))
6199 gcc_assert (access_path);
6200 perform_or_defer_access_check (access_path, fn, fn);
6204 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6205 return cp_build_unary_op (ADDR_EXPR, fn, 0, flags);
6208 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6209 will mark the function as addressed, but here we must do it
6211 cxx_mark_addressable (fn);
6217 /* This function will instantiate the type of the expression given in
6218 RHS to match the type of LHSTYPE. If errors exist, then return
6219 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6220 we complain on errors. If we are not complaining, never modify rhs,
6221 as overload resolution wants to try many possible instantiations, in
6222 the hope that at least one will work.
6224 For non-recursive calls, LHSTYPE should be a function, pointer to
6225 function, or a pointer to member function. */
6228 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6230 tsubst_flags_t flags_in = flags;
6231 tree access_path = NULL_TREE;
6233 flags &= ~tf_ptrmem_ok;
6235 if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
6237 if (flags & tf_error)
6238 error ("not enough type information");
6239 return error_mark_node;
6242 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6244 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6246 if (flag_ms_extensions
6247 && TYPE_PTRMEMFUNC_P (lhstype)
6248 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6249 /* Microsoft allows `A::f' to be resolved to a
6250 pointer-to-member. */
6254 if (flags & tf_error)
6255 error ("argument of type %qT does not match %qT",
6256 TREE_TYPE (rhs), lhstype);
6257 return error_mark_node;
6261 if (TREE_CODE (rhs) == BASELINK)
6263 access_path = BASELINK_ACCESS_BINFO (rhs);
6264 rhs = BASELINK_FUNCTIONS (rhs);
6267 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6268 deduce any type information. */
6269 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6271 if (flags & tf_error)
6272 error ("not enough type information");
6273 return error_mark_node;
6276 /* There only a few kinds of expressions that may have a type
6277 dependent on overload resolution. */
6278 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6279 || TREE_CODE (rhs) == COMPONENT_REF
6280 || TREE_CODE (rhs) == COMPOUND_EXPR
6281 || really_overloaded_fn (rhs));
6283 /* We don't overwrite rhs if it is an overloaded function.
6284 Copying it would destroy the tree link. */
6285 if (TREE_CODE (rhs) != OVERLOAD)
6286 rhs = copy_node (rhs);
6288 /* This should really only be used when attempting to distinguish
6289 what sort of a pointer to function we have. For now, any
6290 arithmetic operation which is not supported on pointers
6291 is rejected as an error. */
6293 switch (TREE_CODE (rhs))
6297 tree member = TREE_OPERAND (rhs, 1);
6299 member = instantiate_type (lhstype, member, flags);
6300 if (member != error_mark_node
6301 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6302 /* Do not lose object's side effects. */
6303 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6304 TREE_OPERAND (rhs, 0), member);
6309 rhs = TREE_OPERAND (rhs, 1);
6310 if (BASELINK_P (rhs))
6311 return instantiate_type (lhstype, rhs, flags_in);
6313 /* This can happen if we are forming a pointer-to-member for a
6315 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6319 case TEMPLATE_ID_EXPR:
6321 tree fns = TREE_OPERAND (rhs, 0);
6322 tree args = TREE_OPERAND (rhs, 1);
6325 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6326 /*template_only=*/true,
6333 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6334 /*template_only=*/false,
6335 /*explicit_targs=*/NULL_TREE,
6339 TREE_OPERAND (rhs, 0)
6340 = instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6341 if (TREE_OPERAND (rhs, 0) == error_mark_node)
6342 return error_mark_node;
6343 TREE_OPERAND (rhs, 1)
6344 = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags);
6345 if (TREE_OPERAND (rhs, 1) == error_mark_node)
6346 return error_mark_node;
6348 TREE_TYPE (rhs) = lhstype;
6353 if (PTRMEM_OK_P (rhs))
6354 flags |= tf_ptrmem_ok;
6356 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6360 return error_mark_node;
6365 return error_mark_node;
6368 /* Return the name of the virtual function pointer field
6369 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6370 this may have to look back through base types to find the
6371 ultimate field name. (For single inheritance, these could
6372 all be the same name. Who knows for multiple inheritance). */
6375 get_vfield_name (tree type)
6377 tree binfo, base_binfo;
6380 for (binfo = TYPE_BINFO (type);
6381 BINFO_N_BASE_BINFOS (binfo);
6384 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6386 if (BINFO_VIRTUAL_P (base_binfo)
6387 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6391 type = BINFO_TYPE (binfo);
6392 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6393 + TYPE_NAME_LENGTH (type) + 2);
6394 sprintf (buf, VFIELD_NAME_FORMAT,
6395 IDENTIFIER_POINTER (constructor_name (type)));
6396 return get_identifier (buf);
6400 print_class_statistics (void)
6402 #ifdef GATHER_STATISTICS
6403 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6404 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6407 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6408 n_vtables, n_vtable_searches);
6409 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6410 n_vtable_entries, n_vtable_elems);
6415 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6416 according to [class]:
6417 The class-name is also inserted
6418 into the scope of the class itself. For purposes of access checking,
6419 the inserted class name is treated as if it were a public member name. */
6422 build_self_reference (void)
6424 tree name = constructor_name (current_class_type);
6425 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6428 DECL_NONLOCAL (value) = 1;
6429 DECL_CONTEXT (value) = current_class_type;
6430 DECL_ARTIFICIAL (value) = 1;
6431 SET_DECL_SELF_REFERENCE_P (value);
6433 if (processing_template_decl)
6434 value = push_template_decl (value);
6436 saved_cas = current_access_specifier;
6437 current_access_specifier = access_public_node;
6438 finish_member_declaration (value);
6439 current_access_specifier = saved_cas;
6442 /* Returns 1 if TYPE contains only padding bytes. */
6445 is_empty_class (tree type)
6447 if (type == error_mark_node)
6450 if (! MAYBE_CLASS_TYPE_P (type))
6453 /* In G++ 3.2, whether or not a class was empty was determined by
6454 looking at its size. */
6455 if (abi_version_at_least (2))
6456 return CLASSTYPE_EMPTY_P (type);
6458 return integer_zerop (CLASSTYPE_SIZE (type));
6461 /* Returns true if TYPE contains an empty class. */
6464 contains_empty_class_p (tree type)
6466 if (is_empty_class (type))
6468 if (CLASS_TYPE_P (type))
6475 for (binfo = TYPE_BINFO (type), i = 0;
6476 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6477 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6479 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6480 if (TREE_CODE (field) == FIELD_DECL
6481 && !DECL_ARTIFICIAL (field)
6482 && is_empty_class (TREE_TYPE (field)))
6485 else if (TREE_CODE (type) == ARRAY_TYPE)
6486 return contains_empty_class_p (TREE_TYPE (type));
6490 /* Note that NAME was looked up while the current class was being
6491 defined and that the result of that lookup was DECL. */
6494 maybe_note_name_used_in_class (tree name, tree decl)
6496 splay_tree names_used;
6498 /* If we're not defining a class, there's nothing to do. */
6499 if (!(innermost_scope_kind() == sk_class
6500 && TYPE_BEING_DEFINED (current_class_type)))
6503 /* If there's already a binding for this NAME, then we don't have
6504 anything to worry about. */
6505 if (lookup_member (current_class_type, name,
6506 /*protect=*/0, /*want_type=*/false))
6509 if (!current_class_stack[current_class_depth - 1].names_used)
6510 current_class_stack[current_class_depth - 1].names_used
6511 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6512 names_used = current_class_stack[current_class_depth - 1].names_used;
6514 splay_tree_insert (names_used,
6515 (splay_tree_key) name,
6516 (splay_tree_value) decl);
6519 /* Note that NAME was declared (as DECL) in the current class. Check
6520 to see that the declaration is valid. */
6523 note_name_declared_in_class (tree name, tree decl)
6525 splay_tree names_used;
6528 /* Look to see if we ever used this name. */
6530 = current_class_stack[current_class_depth - 1].names_used;
6534 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6537 /* [basic.scope.class]
6539 A name N used in a class S shall refer to the same declaration
6540 in its context and when re-evaluated in the completed scope of
6542 permerror (input_location, "declaration of %q#D", decl);
6543 permerror (input_location, "changes meaning of %qD from %q+#D",
6544 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6548 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6549 Secondary vtables are merged with primary vtables; this function
6550 will return the VAR_DECL for the primary vtable. */
6553 get_vtbl_decl_for_binfo (tree binfo)
6557 decl = BINFO_VTABLE (binfo);
6558 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
6560 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6561 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6564 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6569 /* Returns the binfo for the primary base of BINFO. If the resulting
6570 BINFO is a virtual base, and it is inherited elsewhere in the
6571 hierarchy, then the returned binfo might not be the primary base of
6572 BINFO in the complete object. Check BINFO_PRIMARY_P or
6573 BINFO_LOST_PRIMARY_P to be sure. */
6576 get_primary_binfo (tree binfo)
6580 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6584 return copied_binfo (primary_base, binfo);
6587 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6590 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6593 fprintf (stream, "%*s", indent, "");
6597 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6598 INDENT should be zero when called from the top level; it is
6599 incremented recursively. IGO indicates the next expected BINFO in
6600 inheritance graph ordering. */
6603 dump_class_hierarchy_r (FILE *stream,
6613 indented = maybe_indent_hierarchy (stream, indent, 0);
6614 fprintf (stream, "%s (0x%lx) ",
6615 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6616 (unsigned long) binfo);
6619 fprintf (stream, "alternative-path\n");
6622 igo = TREE_CHAIN (binfo);
6624 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6625 tree_low_cst (BINFO_OFFSET (binfo), 0));
6626 if (is_empty_class (BINFO_TYPE (binfo)))
6627 fprintf (stream, " empty");
6628 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6629 fprintf (stream, " nearly-empty");
6630 if (BINFO_VIRTUAL_P (binfo))
6631 fprintf (stream, " virtual");
6632 fprintf (stream, "\n");
6635 if (BINFO_PRIMARY_P (binfo))
6637 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6638 fprintf (stream, " primary-for %s (0x%lx)",
6639 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6640 TFF_PLAIN_IDENTIFIER),
6641 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6643 if (BINFO_LOST_PRIMARY_P (binfo))
6645 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6646 fprintf (stream, " lost-primary");
6649 fprintf (stream, "\n");
6651 if (!(flags & TDF_SLIM))
6655 if (BINFO_SUBVTT_INDEX (binfo))
6657 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6658 fprintf (stream, " subvttidx=%s",
6659 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6660 TFF_PLAIN_IDENTIFIER));
6662 if (BINFO_VPTR_INDEX (binfo))
6664 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6665 fprintf (stream, " vptridx=%s",
6666 expr_as_string (BINFO_VPTR_INDEX (binfo),
6667 TFF_PLAIN_IDENTIFIER));
6669 if (BINFO_VPTR_FIELD (binfo))
6671 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6672 fprintf (stream, " vbaseoffset=%s",
6673 expr_as_string (BINFO_VPTR_FIELD (binfo),
6674 TFF_PLAIN_IDENTIFIER));
6676 if (BINFO_VTABLE (binfo))
6678 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6679 fprintf (stream, " vptr=%s",
6680 expr_as_string (BINFO_VTABLE (binfo),
6681 TFF_PLAIN_IDENTIFIER));
6685 fprintf (stream, "\n");
6688 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6689 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6694 /* Dump the BINFO hierarchy for T. */
6697 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6699 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6700 fprintf (stream, " size=%lu align=%lu\n",
6701 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6702 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6703 fprintf (stream, " base size=%lu base align=%lu\n",
6704 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6706 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6708 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6709 fprintf (stream, "\n");
6712 /* Debug interface to hierarchy dumping. */
6715 debug_class (tree t)
6717 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6721 dump_class_hierarchy (tree t)
6724 FILE *stream = dump_begin (TDI_class, &flags);
6728 dump_class_hierarchy_1 (stream, flags, t);
6729 dump_end (TDI_class, stream);
6734 dump_array (FILE * stream, tree decl)
6737 unsigned HOST_WIDE_INT ix;
6739 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6741 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6743 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6744 fprintf (stream, " %s entries",
6745 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6746 TFF_PLAIN_IDENTIFIER));
6747 fprintf (stream, "\n");
6749 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
6751 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
6752 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
6756 dump_vtable (tree t, tree binfo, tree vtable)
6759 FILE *stream = dump_begin (TDI_class, &flags);
6764 if (!(flags & TDF_SLIM))
6766 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6768 fprintf (stream, "%s for %s",
6769 ctor_vtbl_p ? "Construction vtable" : "Vtable",
6770 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6773 if (!BINFO_VIRTUAL_P (binfo))
6774 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6775 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6777 fprintf (stream, "\n");
6778 dump_array (stream, vtable);
6779 fprintf (stream, "\n");
6782 dump_end (TDI_class, stream);
6786 dump_vtt (tree t, tree vtt)
6789 FILE *stream = dump_begin (TDI_class, &flags);
6794 if (!(flags & TDF_SLIM))
6796 fprintf (stream, "VTT for %s\n",
6797 type_as_string (t, TFF_PLAIN_IDENTIFIER));
6798 dump_array (stream, vtt);
6799 fprintf (stream, "\n");
6802 dump_end (TDI_class, stream);
6805 /* Dump a function or thunk and its thunkees. */
6808 dump_thunk (FILE *stream, int indent, tree thunk)
6810 static const char spaces[] = " ";
6811 tree name = DECL_NAME (thunk);
6814 fprintf (stream, "%.*s%p %s %s", indent, spaces,
6816 !DECL_THUNK_P (thunk) ? "function"
6817 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6818 name ? IDENTIFIER_POINTER (name) : "<unset>");
6819 if (DECL_THUNK_P (thunk))
6821 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6822 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6824 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6825 if (!virtual_adjust)
6827 else if (DECL_THIS_THUNK_P (thunk))
6828 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
6829 tree_low_cst (virtual_adjust, 0));
6831 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6832 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6833 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6834 if (THUNK_ALIAS (thunk))
6835 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6837 fprintf (stream, "\n");
6838 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6839 dump_thunk (stream, indent + 2, thunks);
6842 /* Dump the thunks for FN. */
6845 debug_thunks (tree fn)
6847 dump_thunk (stderr, 0, fn);
6850 /* Virtual function table initialization. */
6852 /* Create all the necessary vtables for T and its base classes. */
6855 finish_vtbls (tree t)
6860 /* We lay out the primary and secondary vtables in one contiguous
6861 vtable. The primary vtable is first, followed by the non-virtual
6862 secondary vtables in inheritance graph order. */
6863 list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6864 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6865 TYPE_BINFO (t), t, list);
6867 /* Then come the virtual bases, also in inheritance graph order. */
6868 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6870 if (!BINFO_VIRTUAL_P (vbase))
6872 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6875 if (BINFO_VTABLE (TYPE_BINFO (t)))
6876 initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
6879 /* Initialize the vtable for BINFO with the INITS. */
6882 initialize_vtable (tree binfo, tree inits)
6886 layout_vtable_decl (binfo, list_length (inits));
6887 decl = get_vtbl_decl_for_binfo (binfo);
6888 initialize_artificial_var (decl, inits);
6889 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
6892 /* Build the VTT (virtual table table) for T.
6893 A class requires a VTT if it has virtual bases.
6896 1 - primary virtual pointer for complete object T
6897 2 - secondary VTTs for each direct non-virtual base of T which requires a
6899 3 - secondary virtual pointers for each direct or indirect base of T which
6900 has virtual bases or is reachable via a virtual path from T.
6901 4 - secondary VTTs for each direct or indirect virtual base of T.
6903 Secondary VTTs look like complete object VTTs without part 4. */
6913 /* Build up the initializers for the VTT. */
6915 index = size_zero_node;
6916 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
6918 /* If we didn't need a VTT, we're done. */
6922 /* Figure out the type of the VTT. */
6923 type = build_index_type (size_int (list_length (inits) - 1));
6924 type = build_cplus_array_type (const_ptr_type_node, type);
6926 /* Now, build the VTT object itself. */
6927 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
6928 initialize_artificial_var (vtt, inits);
6929 /* Add the VTT to the vtables list. */
6930 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
6931 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
6936 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
6937 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
6938 and CHAIN the vtable pointer for this binfo after construction is
6939 complete. VALUE can also be another BINFO, in which case we recurse. */
6942 binfo_ctor_vtable (tree binfo)
6948 vt = BINFO_VTABLE (binfo);
6949 if (TREE_CODE (vt) == TREE_LIST)
6950 vt = TREE_VALUE (vt);
6951 if (TREE_CODE (vt) == TREE_BINFO)
6960 /* Data for secondary VTT initialization. */
6961 typedef struct secondary_vptr_vtt_init_data_s
6963 /* Is this the primary VTT? */
6966 /* Current index into the VTT. */
6969 /* TREE_LIST of initializers built up. */
6972 /* The type being constructed by this secondary VTT. */
6973 tree type_being_constructed;
6974 } secondary_vptr_vtt_init_data;
6976 /* Recursively build the VTT-initializer for BINFO (which is in the
6977 hierarchy dominated by T). INITS points to the end of the initializer
6978 list to date. INDEX is the VTT index where the next element will be
6979 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
6980 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
6981 for virtual bases of T. When it is not so, we build the constructor
6982 vtables for the BINFO-in-T variant. */
6985 build_vtt_inits (tree binfo, tree t, tree *inits, tree *index)
6990 tree secondary_vptrs;
6991 secondary_vptr_vtt_init_data data;
6992 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
6994 /* We only need VTTs for subobjects with virtual bases. */
6995 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
6998 /* We need to use a construction vtable if this is not the primary
7002 build_ctor_vtbl_group (binfo, t);
7004 /* Record the offset in the VTT where this sub-VTT can be found. */
7005 BINFO_SUBVTT_INDEX (binfo) = *index;
7008 /* Add the address of the primary vtable for the complete object. */
7009 init = binfo_ctor_vtable (binfo);
7010 *inits = build_tree_list (NULL_TREE, init);
7011 inits = &TREE_CHAIN (*inits);
7014 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7015 BINFO_VPTR_INDEX (binfo) = *index;
7017 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7019 /* Recursively add the secondary VTTs for non-virtual bases. */
7020 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7021 if (!BINFO_VIRTUAL_P (b))
7022 inits = build_vtt_inits (b, t, inits, index);
7024 /* Add secondary virtual pointers for all subobjects of BINFO with
7025 either virtual bases or reachable along a virtual path, except
7026 subobjects that are non-virtual primary bases. */
7027 data.top_level_p = top_level_p;
7028 data.index = *index;
7030 data.type_being_constructed = BINFO_TYPE (binfo);
7032 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7034 *index = data.index;
7036 /* The secondary vptrs come back in reverse order. After we reverse
7037 them, and add the INITS, the last init will be the first element
7039 secondary_vptrs = data.inits;
7040 if (secondary_vptrs)
7042 *inits = nreverse (secondary_vptrs);
7043 inits = &TREE_CHAIN (secondary_vptrs);
7044 gcc_assert (*inits == NULL_TREE);
7048 /* Add the secondary VTTs for virtual bases in inheritance graph
7050 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7052 if (!BINFO_VIRTUAL_P (b))
7055 inits = build_vtt_inits (b, t, inits, index);
7058 /* Remove the ctor vtables we created. */
7059 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7064 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7065 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7068 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7070 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7072 /* We don't care about bases that don't have vtables. */
7073 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7074 return dfs_skip_bases;
7076 /* We're only interested in proper subobjects of the type being
7078 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7081 /* We're only interested in bases with virtual bases or reachable
7082 via a virtual path from the type being constructed. */
7083 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7084 || binfo_via_virtual (binfo, data->type_being_constructed)))
7085 return dfs_skip_bases;
7087 /* We're not interested in non-virtual primary bases. */
7088 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7091 /* Record the index where this secondary vptr can be found. */
7092 if (data->top_level_p)
7094 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7095 BINFO_VPTR_INDEX (binfo) = data->index;
7097 if (BINFO_VIRTUAL_P (binfo))
7099 /* It's a primary virtual base, and this is not a
7100 construction vtable. Find the base this is primary of in
7101 the inheritance graph, and use that base's vtable
7103 while (BINFO_PRIMARY_P (binfo))
7104 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7108 /* Add the initializer for the secondary vptr itself. */
7109 data->inits = tree_cons (NULL_TREE, binfo_ctor_vtable (binfo), data->inits);
7111 /* Advance the vtt index. */
7112 data->index = size_binop (PLUS_EXPR, data->index,
7113 TYPE_SIZE_UNIT (ptr_type_node));
7118 /* Called from build_vtt_inits via dfs_walk. After building
7119 constructor vtables and generating the sub-vtt from them, we need
7120 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7121 binfo of the base whose sub vtt was generated. */
7124 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7126 tree vtable = BINFO_VTABLE (binfo);
7128 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7129 /* If this class has no vtable, none of its bases do. */
7130 return dfs_skip_bases;
7133 /* This might be a primary base, so have no vtable in this
7137 /* If we scribbled the construction vtable vptr into BINFO, clear it
7139 if (TREE_CODE (vtable) == TREE_LIST
7140 && (TREE_PURPOSE (vtable) == (tree) data))
7141 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7146 /* Build the construction vtable group for BINFO which is in the
7147 hierarchy dominated by T. */
7150 build_ctor_vtbl_group (tree binfo, tree t)
7159 /* See if we've already created this construction vtable group. */
7160 id = mangle_ctor_vtbl_for_type (t, binfo);
7161 if (IDENTIFIER_GLOBAL_VALUE (id))
7164 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7165 /* Build a version of VTBL (with the wrong type) for use in
7166 constructing the addresses of secondary vtables in the
7167 construction vtable group. */
7168 vtbl = build_vtable (t, id, ptr_type_node);
7169 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7170 list = build_tree_list (vtbl, NULL_TREE);
7171 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7174 /* Add the vtables for each of our virtual bases using the vbase in T
7176 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7178 vbase = TREE_CHAIN (vbase))
7182 if (!BINFO_VIRTUAL_P (vbase))
7184 b = copied_binfo (vbase, binfo);
7186 accumulate_vtbl_inits (b, vbase, binfo, t, list);
7188 inits = TREE_VALUE (list);
7190 /* Figure out the type of the construction vtable. */
7191 type = build_index_type (size_int (list_length (inits) - 1));
7192 type = build_cplus_array_type (vtable_entry_type, type);
7194 TREE_TYPE (vtbl) = type;
7195 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7196 layout_decl (vtbl, 0);
7198 /* Initialize the construction vtable. */
7199 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7200 initialize_artificial_var (vtbl, inits);
7201 dump_vtable (t, binfo, vtbl);
7204 /* Add the vtbl initializers for BINFO (and its bases other than
7205 non-virtual primaries) to the list of INITS. BINFO is in the
7206 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7207 the constructor the vtbl inits should be accumulated for. (If this
7208 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7209 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7210 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7211 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7212 but are not necessarily the same in terms of layout. */
7215 accumulate_vtbl_inits (tree binfo,
7223 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7225 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7227 /* If it doesn't have a vptr, we don't do anything. */
7228 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7231 /* If we're building a construction vtable, we're not interested in
7232 subobjects that don't require construction vtables. */
7234 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7235 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7238 /* Build the initializers for the BINFO-in-T vtable. */
7240 = chainon (TREE_VALUE (inits),
7241 dfs_accumulate_vtbl_inits (binfo, orig_binfo,
7242 rtti_binfo, t, inits));
7244 /* Walk the BINFO and its bases. We walk in preorder so that as we
7245 initialize each vtable we can figure out at what offset the
7246 secondary vtable lies from the primary vtable. We can't use
7247 dfs_walk here because we need to iterate through bases of BINFO
7248 and RTTI_BINFO simultaneously. */
7249 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7251 /* Skip virtual bases. */
7252 if (BINFO_VIRTUAL_P (base_binfo))
7254 accumulate_vtbl_inits (base_binfo,
7255 BINFO_BASE_BINFO (orig_binfo, i),
7261 /* Called from accumulate_vtbl_inits. Returns the initializers for
7262 the BINFO vtable. */
7265 dfs_accumulate_vtbl_inits (tree binfo,
7271 tree inits = NULL_TREE;
7272 tree vtbl = NULL_TREE;
7273 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7276 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7278 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7279 primary virtual base. If it is not the same primary in
7280 the hierarchy of T, we'll need to generate a ctor vtable
7281 for it, to place at its location in T. If it is the same
7282 primary, we still need a VTT entry for the vtable, but it
7283 should point to the ctor vtable for the base it is a
7284 primary for within the sub-hierarchy of RTTI_BINFO.
7286 There are three possible cases:
7288 1) We are in the same place.
7289 2) We are a primary base within a lost primary virtual base of
7291 3) We are primary to something not a base of RTTI_BINFO. */
7294 tree last = NULL_TREE;
7296 /* First, look through the bases we are primary to for RTTI_BINFO
7297 or a virtual base. */
7299 while (BINFO_PRIMARY_P (b))
7301 b = BINFO_INHERITANCE_CHAIN (b);
7303 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7306 /* If we run out of primary links, keep looking down our
7307 inheritance chain; we might be an indirect primary. */
7308 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7309 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7313 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7314 base B and it is a base of RTTI_BINFO, this is case 2. In
7315 either case, we share our vtable with LAST, i.e. the
7316 derived-most base within B of which we are a primary. */
7318 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7319 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7320 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7321 binfo_ctor_vtable after everything's been set up. */
7324 /* Otherwise, this is case 3 and we get our own. */
7326 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7334 /* Compute the initializer for this vtable. */
7335 inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7338 /* Figure out the position to which the VPTR should point. */
7339 vtbl = TREE_PURPOSE (l);
7340 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7341 index = size_binop (PLUS_EXPR,
7342 size_int (non_fn_entries),
7343 size_int (list_length (TREE_VALUE (l))));
7344 index = size_binop (MULT_EXPR,
7345 TYPE_SIZE_UNIT (vtable_entry_type),
7347 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7351 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7352 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7353 straighten this out. */
7354 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7355 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7358 /* For an ordinary vtable, set BINFO_VTABLE. */
7359 BINFO_VTABLE (binfo) = vtbl;
7364 static GTY(()) tree abort_fndecl_addr;
7366 /* Construct the initializer for BINFO's virtual function table. BINFO
7367 is part of the hierarchy dominated by T. If we're building a
7368 construction vtable, the ORIG_BINFO is the binfo we should use to
7369 find the actual function pointers to put in the vtable - but they
7370 can be overridden on the path to most-derived in the graph that
7371 ORIG_BINFO belongs. Otherwise,
7372 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7373 BINFO that should be indicated by the RTTI information in the
7374 vtable; it will be a base class of T, rather than T itself, if we
7375 are building a construction vtable.
7377 The value returned is a TREE_LIST suitable for wrapping in a
7378 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7379 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7380 number of non-function entries in the vtable.
7382 It might seem that this function should never be called with a
7383 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7384 base is always subsumed by a derived class vtable. However, when
7385 we are building construction vtables, we do build vtables for
7386 primary bases; we need these while the primary base is being
7390 build_vtbl_initializer (tree binfo,
7394 int* non_fn_entries_p)
7401 VEC(tree,gc) *vbases;
7403 /* Initialize VID. */
7404 memset (&vid, 0, sizeof (vid));
7407 vid.rtti_binfo = rtti_binfo;
7408 vid.last_init = &vid.inits;
7409 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7410 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7411 vid.generate_vcall_entries = true;
7412 /* The first vbase or vcall offset is at index -3 in the vtable. */
7413 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7415 /* Add entries to the vtable for RTTI. */
7416 build_rtti_vtbl_entries (binfo, &vid);
7418 /* Create an array for keeping track of the functions we've
7419 processed. When we see multiple functions with the same
7420 signature, we share the vcall offsets. */
7421 vid.fns = VEC_alloc (tree, gc, 32);
7422 /* Add the vcall and vbase offset entries. */
7423 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7425 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7426 build_vbase_offset_vtbl_entries. */
7427 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7428 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7429 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7431 /* If the target requires padding between data entries, add that now. */
7432 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7436 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7441 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7442 add = tree_cons (NULL_TREE,
7443 build1 (NOP_EXPR, vtable_entry_type,
7450 if (non_fn_entries_p)
7451 *non_fn_entries_p = list_length (vid.inits);
7453 /* Go through all the ordinary virtual functions, building up
7455 vfun_inits = NULL_TREE;
7456 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7460 tree fn, fn_original;
7461 tree init = NULL_TREE;
7465 if (DECL_THUNK_P (fn))
7467 if (!DECL_NAME (fn))
7469 if (THUNK_ALIAS (fn))
7471 fn = THUNK_ALIAS (fn);
7474 fn_original = THUNK_TARGET (fn);
7477 /* If the only definition of this function signature along our
7478 primary base chain is from a lost primary, this vtable slot will
7479 never be used, so just zero it out. This is important to avoid
7480 requiring extra thunks which cannot be generated with the function.
7482 We first check this in update_vtable_entry_for_fn, so we handle
7483 restored primary bases properly; we also need to do it here so we
7484 zero out unused slots in ctor vtables, rather than filling them
7485 with erroneous values (though harmless, apart from relocation
7487 for (b = binfo; ; b = get_primary_binfo (b))
7489 /* We found a defn before a lost primary; go ahead as normal. */
7490 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7493 /* The nearest definition is from a lost primary; clear the
7495 if (BINFO_LOST_PRIMARY_P (b))
7497 init = size_zero_node;
7504 /* Pull the offset for `this', and the function to call, out of
7506 delta = BV_DELTA (v);
7507 vcall_index = BV_VCALL_INDEX (v);
7509 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7510 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7512 /* You can't call an abstract virtual function; it's abstract.
7513 So, we replace these functions with __pure_virtual. */
7514 if (DECL_PURE_VIRTUAL_P (fn_original))
7517 if (abort_fndecl_addr == NULL)
7518 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7519 init = abort_fndecl_addr;
7523 if (!integer_zerop (delta) || vcall_index)
7525 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7526 if (!DECL_NAME (fn))
7529 /* Take the address of the function, considering it to be of an
7530 appropriate generic type. */
7531 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7535 /* And add it to the chain of initializers. */
7536 if (TARGET_VTABLE_USES_DESCRIPTORS)
7539 if (init == size_zero_node)
7540 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7541 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7543 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7545 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7546 TREE_OPERAND (init, 0),
7547 build_int_cst (NULL_TREE, i));
7548 TREE_CONSTANT (fdesc) = 1;
7550 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7554 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7557 /* The initializers for virtual functions were built up in reverse
7558 order; straighten them out now. */
7559 vfun_inits = nreverse (vfun_inits);
7561 /* The negative offset initializers are also in reverse order. */
7562 vid.inits = nreverse (vid.inits);
7564 /* Chain the two together. */
7565 return chainon (vid.inits, vfun_inits);
7568 /* Adds to vid->inits the initializers for the vbase and vcall
7569 offsets in BINFO, which is in the hierarchy dominated by T. */
7572 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7576 /* If this is a derived class, we must first create entries
7577 corresponding to the primary base class. */
7578 b = get_primary_binfo (binfo);
7580 build_vcall_and_vbase_vtbl_entries (b, vid);
7582 /* Add the vbase entries for this base. */
7583 build_vbase_offset_vtbl_entries (binfo, vid);
7584 /* Add the vcall entries for this base. */
7585 build_vcall_offset_vtbl_entries (binfo, vid);
7588 /* Returns the initializers for the vbase offset entries in the vtable
7589 for BINFO (which is part of the class hierarchy dominated by T), in
7590 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7591 where the next vbase offset will go. */
7594 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7598 tree non_primary_binfo;
7600 /* If there are no virtual baseclasses, then there is nothing to
7602 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7607 /* We might be a primary base class. Go up the inheritance hierarchy
7608 until we find the most derived class of which we are a primary base:
7609 it is the offset of that which we need to use. */
7610 non_primary_binfo = binfo;
7611 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7615 /* If we have reached a virtual base, then it must be a primary
7616 base (possibly multi-level) of vid->binfo, or we wouldn't
7617 have called build_vcall_and_vbase_vtbl_entries for it. But it
7618 might be a lost primary, so just skip down to vid->binfo. */
7619 if (BINFO_VIRTUAL_P (non_primary_binfo))
7621 non_primary_binfo = vid->binfo;
7625 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7626 if (get_primary_binfo (b) != non_primary_binfo)
7628 non_primary_binfo = b;
7631 /* Go through the virtual bases, adding the offsets. */
7632 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7634 vbase = TREE_CHAIN (vbase))
7639 if (!BINFO_VIRTUAL_P (vbase))
7642 /* Find the instance of this virtual base in the complete
7644 b = copied_binfo (vbase, binfo);
7646 /* If we've already got an offset for this virtual base, we
7647 don't need another one. */
7648 if (BINFO_VTABLE_PATH_MARKED (b))
7650 BINFO_VTABLE_PATH_MARKED (b) = 1;
7652 /* Figure out where we can find this vbase offset. */
7653 delta = size_binop (MULT_EXPR,
7656 TYPE_SIZE_UNIT (vtable_entry_type)));
7657 if (vid->primary_vtbl_p)
7658 BINFO_VPTR_FIELD (b) = delta;
7660 if (binfo != TYPE_BINFO (t))
7661 /* The vbase offset had better be the same. */
7662 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7664 /* The next vbase will come at a more negative offset. */
7665 vid->index = size_binop (MINUS_EXPR, vid->index,
7666 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7668 /* The initializer is the delta from BINFO to this virtual base.
7669 The vbase offsets go in reverse inheritance-graph order, and
7670 we are walking in inheritance graph order so these end up in
7672 delta = size_diffop (BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7675 = build_tree_list (NULL_TREE,
7676 fold_build1 (NOP_EXPR,
7679 vid->last_init = &TREE_CHAIN (*vid->last_init);
7683 /* Adds the initializers for the vcall offset entries in the vtable
7684 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7688 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7690 /* We only need these entries if this base is a virtual base. We
7691 compute the indices -- but do not add to the vtable -- when
7692 building the main vtable for a class. */
7693 if (binfo == TYPE_BINFO (vid->derived)
7694 || (BINFO_VIRTUAL_P (binfo)
7695 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7696 correspond to VID->DERIVED), we are building a primary
7697 construction virtual table. Since this is a primary
7698 virtual table, we do not need the vcall offsets for
7700 && binfo != vid->rtti_binfo))
7702 /* We need a vcall offset for each of the virtual functions in this
7703 vtable. For example:
7705 class A { virtual void f (); };
7706 class B1 : virtual public A { virtual void f (); };
7707 class B2 : virtual public A { virtual void f (); };
7708 class C: public B1, public B2 { virtual void f (); };
7710 A C object has a primary base of B1, which has a primary base of A. A
7711 C also has a secondary base of B2, which no longer has a primary base
7712 of A. So the B2-in-C construction vtable needs a secondary vtable for
7713 A, which will adjust the A* to a B2* to call f. We have no way of
7714 knowing what (or even whether) this offset will be when we define B2,
7715 so we store this "vcall offset" in the A sub-vtable and look it up in
7716 a "virtual thunk" for B2::f.
7718 We need entries for all the functions in our primary vtable and
7719 in our non-virtual bases' secondary vtables. */
7721 /* If we are just computing the vcall indices -- but do not need
7722 the actual entries -- not that. */
7723 if (!BINFO_VIRTUAL_P (binfo))
7724 vid->generate_vcall_entries = false;
7725 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7726 add_vcall_offset_vtbl_entries_r (binfo, vid);
7730 /* Build vcall offsets, starting with those for BINFO. */
7733 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7739 /* Don't walk into virtual bases -- except, of course, for the
7740 virtual base for which we are building vcall offsets. Any
7741 primary virtual base will have already had its offsets generated
7742 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7743 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7746 /* If BINFO has a primary base, process it first. */
7747 primary_binfo = get_primary_binfo (binfo);
7749 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7751 /* Add BINFO itself to the list. */
7752 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7754 /* Scan the non-primary bases of BINFO. */
7755 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7756 if (base_binfo != primary_binfo)
7757 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7760 /* Called from build_vcall_offset_vtbl_entries_r. */
7763 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7765 /* Make entries for the rest of the virtuals. */
7766 if (abi_version_at_least (2))
7770 /* The ABI requires that the methods be processed in declaration
7771 order. G++ 3.2 used the order in the vtable. */
7772 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7774 orig_fn = TREE_CHAIN (orig_fn))
7775 if (DECL_VINDEX (orig_fn))
7776 add_vcall_offset (orig_fn, binfo, vid);
7780 tree derived_virtuals;
7783 /* If BINFO is a primary base, the most derived class which has
7784 BINFO as a primary base; otherwise, just BINFO. */
7785 tree non_primary_binfo;
7787 /* We might be a primary base class. Go up the inheritance hierarchy
7788 until we find the most derived class of which we are a primary base:
7789 it is the BINFO_VIRTUALS there that we need to consider. */
7790 non_primary_binfo = binfo;
7791 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7795 /* If we have reached a virtual base, then it must be vid->vbase,
7796 because we ignore other virtual bases in
7797 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7798 base (possibly multi-level) of vid->binfo, or we wouldn't
7799 have called build_vcall_and_vbase_vtbl_entries for it. But it
7800 might be a lost primary, so just skip down to vid->binfo. */
7801 if (BINFO_VIRTUAL_P (non_primary_binfo))
7803 gcc_assert (non_primary_binfo == vid->vbase);
7804 non_primary_binfo = vid->binfo;
7808 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7809 if (get_primary_binfo (b) != non_primary_binfo)
7811 non_primary_binfo = b;
7814 if (vid->ctor_vtbl_p)
7815 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7816 where rtti_binfo is the most derived type. */
7818 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7820 for (base_virtuals = BINFO_VIRTUALS (binfo),
7821 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7822 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7824 base_virtuals = TREE_CHAIN (base_virtuals),
7825 derived_virtuals = TREE_CHAIN (derived_virtuals),
7826 orig_virtuals = TREE_CHAIN (orig_virtuals))
7830 /* Find the declaration that originally caused this function to
7831 be present in BINFO_TYPE (binfo). */
7832 orig_fn = BV_FN (orig_virtuals);
7834 /* When processing BINFO, we only want to generate vcall slots for
7835 function slots introduced in BINFO. So don't try to generate
7836 one if the function isn't even defined in BINFO. */
7837 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7840 add_vcall_offset (orig_fn, binfo, vid);
7845 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7848 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7854 /* If there is already an entry for a function with the same
7855 signature as FN, then we do not need a second vcall offset.
7856 Check the list of functions already present in the derived
7858 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7860 if (same_signature_p (derived_entry, orig_fn)
7861 /* We only use one vcall offset for virtual destructors,
7862 even though there are two virtual table entries. */
7863 || (DECL_DESTRUCTOR_P (derived_entry)
7864 && DECL_DESTRUCTOR_P (orig_fn)))
7868 /* If we are building these vcall offsets as part of building
7869 the vtable for the most derived class, remember the vcall
7871 if (vid->binfo == TYPE_BINFO (vid->derived))
7873 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
7874 CLASSTYPE_VCALL_INDICES (vid->derived),
7876 elt->purpose = orig_fn;
7877 elt->value = vid->index;
7880 /* The next vcall offset will be found at a more negative
7882 vid->index = size_binop (MINUS_EXPR, vid->index,
7883 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7885 /* Keep track of this function. */
7886 VEC_safe_push (tree, gc, vid->fns, orig_fn);
7888 if (vid->generate_vcall_entries)
7893 /* Find the overriding function. */
7894 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
7895 if (fn == error_mark_node)
7896 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
7900 base = TREE_VALUE (fn);
7902 /* The vbase we're working on is a primary base of
7903 vid->binfo. But it might be a lost primary, so its
7904 BINFO_OFFSET might be wrong, so we just use the
7905 BINFO_OFFSET from vid->binfo. */
7906 vcall_offset = size_diffop (BINFO_OFFSET (base),
7907 BINFO_OFFSET (vid->binfo));
7908 vcall_offset = fold_build1 (NOP_EXPR, vtable_entry_type,
7911 /* Add the initializer to the vtable. */
7912 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
7913 vid->last_init = &TREE_CHAIN (*vid->last_init);
7917 /* Return vtbl initializers for the RTTI entries corresponding to the
7918 BINFO's vtable. The RTTI entries should indicate the object given
7919 by VID->rtti_binfo. */
7922 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
7931 basetype = BINFO_TYPE (binfo);
7932 t = BINFO_TYPE (vid->rtti_binfo);
7934 /* To find the complete object, we will first convert to our most
7935 primary base, and then add the offset in the vtbl to that value. */
7937 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
7938 && !BINFO_LOST_PRIMARY_P (b))
7942 primary_base = get_primary_binfo (b);
7943 gcc_assert (BINFO_PRIMARY_P (primary_base)
7944 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
7947 offset = size_diffop (BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
7949 /* The second entry is the address of the typeinfo object. */
7951 decl = build_address (get_tinfo_decl (t));
7953 decl = integer_zero_node;
7955 /* Convert the declaration to a type that can be stored in the
7957 init = build_nop (vfunc_ptr_type_node, decl);
7958 *vid->last_init = build_tree_list (NULL_TREE, init);
7959 vid->last_init = &TREE_CHAIN (*vid->last_init);
7961 /* Add the offset-to-top entry. It comes earlier in the vtable than
7962 the typeinfo entry. Convert the offset to look like a
7963 function pointer, so that we can put it in the vtable. */
7964 init = build_nop (vfunc_ptr_type_node, offset);
7965 *vid->last_init = build_tree_list (NULL_TREE, init);
7966 vid->last_init = &TREE_CHAIN (*vid->last_init);
7969 /* Fold a OBJ_TYPE_REF expression to the address of a function.
7970 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
7973 cp_fold_obj_type_ref (tree ref, tree known_type)
7975 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
7976 HOST_WIDE_INT i = 0;
7977 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
7982 i += (TARGET_VTABLE_USES_DESCRIPTORS
7983 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
7989 #ifdef ENABLE_CHECKING
7990 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
7991 DECL_VINDEX (fndecl)));
7994 cgraph_node (fndecl)->local.vtable_method = true;
7996 return build_address (fndecl);
7999 #include "gt-cp-class.h"