1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009
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. */
298 if (cp_unevaluated_operand != 0)
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);
629 aref = build_array_ref (input_location, vtbl, idx);
630 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
636 build_vtbl_ref (tree instance, tree idx)
638 tree aref = build_vtbl_ref_1 (instance, idx);
643 /* Given a stable object pointer INSTANCE_PTR, return an expression which
644 yields a function pointer corresponding to vtable element INDEX. */
647 build_vfn_ref (tree instance_ptr, tree idx)
651 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, 0,
652 tf_warning_or_error),
655 /* When using function descriptors, the address of the
656 vtable entry is treated as a function pointer. */
657 if (TARGET_VTABLE_USES_DESCRIPTORS)
658 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
659 cp_build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1,
660 tf_warning_or_error));
662 /* Remember this as a method reference, for later devirtualization. */
663 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
668 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
669 for the given TYPE. */
672 get_vtable_name (tree type)
674 return mangle_vtbl_for_type (type);
677 /* DECL is an entity associated with TYPE, like a virtual table or an
678 implicitly generated constructor. Determine whether or not DECL
679 should have external or internal linkage at the object file
680 level. This routine does not deal with COMDAT linkage and other
681 similar complexities; it simply sets TREE_PUBLIC if it possible for
682 entities in other translation units to contain copies of DECL, in
686 set_linkage_according_to_type (tree type, tree decl)
688 /* If TYPE involves a local class in a function with internal
689 linkage, then DECL should have internal linkage too. Other local
690 classes have no linkage -- but if their containing functions
691 have external linkage, it makes sense for DECL to have external
692 linkage too. That will allow template definitions to be merged,
694 if (no_linkage_check (type, /*relaxed_p=*/true))
696 TREE_PUBLIC (decl) = 0;
697 DECL_INTERFACE_KNOWN (decl) = 1;
700 TREE_PUBLIC (decl) = 1;
703 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
704 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
705 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
708 build_vtable (tree class_type, tree name, tree vtable_type)
712 decl = build_lang_decl (VAR_DECL, name, vtable_type);
713 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
714 now to avoid confusion in mangle_decl. */
715 SET_DECL_ASSEMBLER_NAME (decl, name);
716 DECL_CONTEXT (decl) = class_type;
717 DECL_ARTIFICIAL (decl) = 1;
718 TREE_STATIC (decl) = 1;
719 TREE_READONLY (decl) = 1;
720 DECL_VIRTUAL_P (decl) = 1;
721 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
722 DECL_VTABLE_OR_VTT_P (decl) = 1;
723 /* At one time the vtable info was grabbed 2 words at a time. This
724 fails on sparc unless you have 8-byte alignment. (tiemann) */
725 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
727 set_linkage_according_to_type (class_type, decl);
728 /* The vtable has not been defined -- yet. */
729 DECL_EXTERNAL (decl) = 1;
730 DECL_NOT_REALLY_EXTERN (decl) = 1;
732 /* Mark the VAR_DECL node representing the vtable itself as a
733 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
734 is rather important that such things be ignored because any
735 effort to actually generate DWARF for them will run into
736 trouble when/if we encounter code like:
739 struct S { virtual void member (); };
741 because the artificial declaration of the vtable itself (as
742 manufactured by the g++ front end) will say that the vtable is
743 a static member of `S' but only *after* the debug output for
744 the definition of `S' has already been output. This causes
745 grief because the DWARF entry for the definition of the vtable
746 will try to refer back to an earlier *declaration* of the
747 vtable as a static member of `S' and there won't be one. We
748 might be able to arrange to have the "vtable static member"
749 attached to the member list for `S' before the debug info for
750 `S' get written (which would solve the problem) but that would
751 require more intrusive changes to the g++ front end. */
752 DECL_IGNORED_P (decl) = 1;
757 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
758 or even complete. If this does not exist, create it. If COMPLETE is
759 nonzero, then complete the definition of it -- that will render it
760 impossible to actually build the vtable, but is useful to get at those
761 which are known to exist in the runtime. */
764 get_vtable_decl (tree type, int complete)
768 if (CLASSTYPE_VTABLES (type))
769 return CLASSTYPE_VTABLES (type);
771 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
772 CLASSTYPE_VTABLES (type) = decl;
776 DECL_EXTERNAL (decl) = 1;
777 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
783 /* Build the primary virtual function table for TYPE. If BINFO is
784 non-NULL, build the vtable starting with the initial approximation
785 that it is the same as the one which is the head of the association
786 list. Returns a nonzero value if a new vtable is actually
790 build_primary_vtable (tree binfo, tree type)
795 decl = get_vtable_decl (type, /*complete=*/0);
799 if (BINFO_NEW_VTABLE_MARKED (binfo))
800 /* We have already created a vtable for this base, so there's
801 no need to do it again. */
804 virtuals = copy_list (BINFO_VIRTUALS (binfo));
805 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
806 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
807 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
811 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
812 virtuals = NULL_TREE;
815 #ifdef GATHER_STATISTICS
817 n_vtable_elems += list_length (virtuals);
820 /* Initialize the association list for this type, based
821 on our first approximation. */
822 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
823 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
824 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
828 /* Give BINFO a new virtual function table which is initialized
829 with a skeleton-copy of its original initialization. The only
830 entry that changes is the `delta' entry, so we can really
831 share a lot of structure.
833 FOR_TYPE is the most derived type which caused this table to
836 Returns nonzero if we haven't met BINFO before.
838 The order in which vtables are built (by calling this function) for
839 an object must remain the same, otherwise a binary incompatibility
843 build_secondary_vtable (tree binfo)
845 if (BINFO_NEW_VTABLE_MARKED (binfo))
846 /* We already created a vtable for this base. There's no need to
850 /* Remember that we've created a vtable for this BINFO, so that we
851 don't try to do so again. */
852 SET_BINFO_NEW_VTABLE_MARKED (binfo);
854 /* Make fresh virtual list, so we can smash it later. */
855 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
857 /* Secondary vtables are laid out as part of the same structure as
858 the primary vtable. */
859 BINFO_VTABLE (binfo) = NULL_TREE;
863 /* Create a new vtable for BINFO which is the hierarchy dominated by
864 T. Return nonzero if we actually created a new vtable. */
867 make_new_vtable (tree t, tree binfo)
869 if (binfo == TYPE_BINFO (t))
870 /* In this case, it is *type*'s vtable we are modifying. We start
871 with the approximation that its vtable is that of the
872 immediate base class. */
873 return build_primary_vtable (binfo, t);
875 /* This is our very own copy of `basetype' to play with. Later,
876 we will fill in all the virtual functions that override the
877 virtual functions in these base classes which are not defined
878 by the current type. */
879 return build_secondary_vtable (binfo);
882 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
883 (which is in the hierarchy dominated by T) list FNDECL as its
884 BV_FN. DELTA is the required constant adjustment from the `this'
885 pointer where the vtable entry appears to the `this' required when
886 the function is actually called. */
889 modify_vtable_entry (tree t,
899 if (fndecl != BV_FN (v)
900 || !tree_int_cst_equal (delta, BV_DELTA (v)))
902 /* We need a new vtable for BINFO. */
903 if (make_new_vtable (t, binfo))
905 /* If we really did make a new vtable, we also made a copy
906 of the BINFO_VIRTUALS list. Now, we have to find the
907 corresponding entry in that list. */
908 *virtuals = BINFO_VIRTUALS (binfo);
909 while (BV_FN (*virtuals) != BV_FN (v))
910 *virtuals = TREE_CHAIN (*virtuals);
914 BV_DELTA (v) = delta;
915 BV_VCALL_INDEX (v) = NULL_TREE;
921 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
922 the USING_DECL naming METHOD. Returns true if the method could be
923 added to the method vec. */
926 add_method (tree type, tree method, tree using_decl)
930 bool template_conv_p = false;
932 VEC(tree,gc) *method_vec;
934 bool insert_p = false;
938 if (method == error_mark_node)
941 complete_p = COMPLETE_TYPE_P (type);
942 conv_p = DECL_CONV_FN_P (method);
944 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
945 && DECL_TEMPLATE_CONV_FN_P (method));
947 method_vec = CLASSTYPE_METHOD_VEC (type);
950 /* Make a new method vector. We start with 8 entries. We must
951 allocate at least two (for constructors and destructors), and
952 we're going to end up with an assignment operator at some
954 method_vec = VEC_alloc (tree, gc, 8);
955 /* Create slots for constructors and destructors. */
956 VEC_quick_push (tree, method_vec, NULL_TREE);
957 VEC_quick_push (tree, method_vec, NULL_TREE);
958 CLASSTYPE_METHOD_VEC (type) = method_vec;
961 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
962 grok_special_member_properties (method);
964 /* Constructors and destructors go in special slots. */
965 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
966 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
967 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
969 slot = CLASSTYPE_DESTRUCTOR_SLOT;
971 if (TYPE_FOR_JAVA (type))
973 if (!DECL_ARTIFICIAL (method))
974 error ("Java class %qT cannot have a destructor", type);
975 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
976 error ("Java class %qT cannot have an implicit non-trivial "
986 /* See if we already have an entry with this name. */
987 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
988 VEC_iterate (tree, method_vec, slot, m);
994 if (TREE_CODE (m) == TEMPLATE_DECL
995 && DECL_TEMPLATE_CONV_FN_P (m))
999 if (conv_p && !DECL_CONV_FN_P (m))
1001 if (DECL_NAME (m) == DECL_NAME (method))
1007 && !DECL_CONV_FN_P (m)
1008 && DECL_NAME (m) > DECL_NAME (method))
1012 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1014 /* Check to see if we've already got this method. */
1015 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1017 tree fn = OVL_CURRENT (fns);
1023 if (TREE_CODE (fn) != TREE_CODE (method))
1026 /* [over.load] Member function declarations with the
1027 same name and the same parameter types cannot be
1028 overloaded if any of them is a static member
1029 function declaration.
1031 [namespace.udecl] When a using-declaration brings names
1032 from a base class into a derived class scope, member
1033 functions in the derived class override and/or hide member
1034 functions with the same name and parameter types in a base
1035 class (rather than conflicting). */
1036 fn_type = TREE_TYPE (fn);
1037 method_type = TREE_TYPE (method);
1038 parms1 = TYPE_ARG_TYPES (fn_type);
1039 parms2 = TYPE_ARG_TYPES (method_type);
1041 /* Compare the quals on the 'this' parm. Don't compare
1042 the whole types, as used functions are treated as
1043 coming from the using class in overload resolution. */
1044 if (! DECL_STATIC_FUNCTION_P (fn)
1045 && ! DECL_STATIC_FUNCTION_P (method)
1046 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1047 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1048 && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
1049 != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
1052 /* For templates, the return type and template parameters
1053 must be identical. */
1054 if (TREE_CODE (fn) == TEMPLATE_DECL
1055 && (!same_type_p (TREE_TYPE (fn_type),
1056 TREE_TYPE (method_type))
1057 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1058 DECL_TEMPLATE_PARMS (method))))
1061 if (! DECL_STATIC_FUNCTION_P (fn))
1062 parms1 = TREE_CHAIN (parms1);
1063 if (! DECL_STATIC_FUNCTION_P (method))
1064 parms2 = TREE_CHAIN (parms2);
1066 if (compparms (parms1, parms2)
1067 && (!DECL_CONV_FN_P (fn)
1068 || same_type_p (TREE_TYPE (fn_type),
1069 TREE_TYPE (method_type))))
1073 if (DECL_CONTEXT (fn) == type)
1074 /* Defer to the local function. */
1076 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1077 error ("repeated using declaration %q+D", using_decl);
1079 error ("using declaration %q+D conflicts with a previous using declaration",
1084 error ("%q+#D cannot be overloaded", method);
1085 error ("with %q+#D", fn);
1088 /* We don't call duplicate_decls here to merge the
1089 declarations because that will confuse things if the
1090 methods have inline definitions. In particular, we
1091 will crash while processing the definitions. */
1096 /* A class should never have more than one destructor. */
1097 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1100 /* Add the new binding. */
1101 overload = build_overload (method, current_fns);
1104 TYPE_HAS_CONVERSION (type) = 1;
1105 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1106 push_class_level_binding (DECL_NAME (method), overload);
1112 /* We only expect to add few methods in the COMPLETE_P case, so
1113 just make room for one more method in that case. */
1115 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1117 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1119 CLASSTYPE_METHOD_VEC (type) = method_vec;
1120 if (slot == VEC_length (tree, method_vec))
1121 VEC_quick_push (tree, method_vec, overload);
1123 VEC_quick_insert (tree, method_vec, slot, overload);
1126 /* Replace the current slot. */
1127 VEC_replace (tree, method_vec, slot, overload);
1131 /* Subroutines of finish_struct. */
1133 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1134 legit, otherwise return 0. */
1137 alter_access (tree t, tree fdecl, tree access)
1141 if (!DECL_LANG_SPECIFIC (fdecl))
1142 retrofit_lang_decl (fdecl);
1144 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1146 elem = purpose_member (t, DECL_ACCESS (fdecl));
1149 if (TREE_VALUE (elem) != access)
1151 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1152 error ("conflicting access specifications for method"
1153 " %q+D, ignored", TREE_TYPE (fdecl));
1155 error ("conflicting access specifications for field %qE, ignored",
1160 /* They're changing the access to the same thing they changed
1161 it to before. That's OK. */
1167 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1168 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1174 /* Process the USING_DECL, which is a member of T. */
1177 handle_using_decl (tree using_decl, tree t)
1179 tree decl = USING_DECL_DECLS (using_decl);
1180 tree name = DECL_NAME (using_decl);
1182 = TREE_PRIVATE (using_decl) ? access_private_node
1183 : TREE_PROTECTED (using_decl) ? access_protected_node
1184 : access_public_node;
1185 tree flist = NULL_TREE;
1188 gcc_assert (!processing_template_decl && decl);
1190 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1193 if (is_overloaded_fn (old_value))
1194 old_value = OVL_CURRENT (old_value);
1196 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1199 old_value = NULL_TREE;
1202 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1204 if (is_overloaded_fn (decl))
1209 else if (is_overloaded_fn (old_value))
1212 /* It's OK to use functions from a base when there are functions with
1213 the same name already present in the current class. */;
1216 error ("%q+D invalid in %q#T", using_decl, t);
1217 error (" because of local method %q+#D with same name",
1218 OVL_CURRENT (old_value));
1222 else if (!DECL_ARTIFICIAL (old_value))
1224 error ("%q+D invalid in %q#T", using_decl, t);
1225 error (" because of local member %q+#D with same name", old_value);
1229 /* Make type T see field decl FDECL with access ACCESS. */
1231 for (; flist; flist = OVL_NEXT (flist))
1233 add_method (t, OVL_CURRENT (flist), using_decl);
1234 alter_access (t, OVL_CURRENT (flist), access);
1237 alter_access (t, decl, access);
1240 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1241 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1242 properties of the bases. */
1245 check_bases (tree t,
1246 int* cant_have_const_ctor_p,
1247 int* no_const_asn_ref_p)
1250 int seen_non_virtual_nearly_empty_base_p;
1254 seen_non_virtual_nearly_empty_base_p = 0;
1256 for (binfo = TYPE_BINFO (t), i = 0;
1257 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1259 tree basetype = TREE_TYPE (base_binfo);
1261 gcc_assert (COMPLETE_TYPE_P (basetype));
1263 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1264 here because the case of virtual functions but non-virtual
1265 dtor is handled in finish_struct_1. */
1266 if (!TYPE_POLYMORPHIC_P (basetype))
1267 warning (OPT_Weffc__,
1268 "base class %q#T has a non-virtual destructor", basetype);
1270 /* If the base class doesn't have copy constructors or
1271 assignment operators that take const references, then the
1272 derived class cannot have such a member automatically
1274 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1275 *cant_have_const_ctor_p = 1;
1276 if (TYPE_HAS_ASSIGN_REF (basetype)
1277 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1278 *no_const_asn_ref_p = 1;
1280 if (BINFO_VIRTUAL_P (base_binfo))
1281 /* A virtual base does not effect nearly emptiness. */
1283 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1285 if (seen_non_virtual_nearly_empty_base_p)
1286 /* And if there is more than one nearly empty base, then the
1287 derived class is not nearly empty either. */
1288 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1290 /* Remember we've seen one. */
1291 seen_non_virtual_nearly_empty_base_p = 1;
1293 else if (!is_empty_class (basetype))
1294 /* If the base class is not empty or nearly empty, then this
1295 class cannot be nearly empty. */
1296 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1298 /* A lot of properties from the bases also apply to the derived
1300 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1301 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1302 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1303 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1304 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1305 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1306 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1307 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1308 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1309 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (basetype);
1313 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1314 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1315 that have had a nearly-empty virtual primary base stolen by some
1316 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1320 determine_primary_bases (tree t)
1323 tree primary = NULL_TREE;
1324 tree type_binfo = TYPE_BINFO (t);
1327 /* Determine the primary bases of our bases. */
1328 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1329 base_binfo = TREE_CHAIN (base_binfo))
1331 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1333 /* See if we're the non-virtual primary of our inheritance
1335 if (!BINFO_VIRTUAL_P (base_binfo))
1337 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1338 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1341 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1342 BINFO_TYPE (parent_primary)))
1343 /* We are the primary binfo. */
1344 BINFO_PRIMARY_P (base_binfo) = 1;
1346 /* Determine if we have a virtual primary base, and mark it so.
1348 if (primary && BINFO_VIRTUAL_P (primary))
1350 tree this_primary = copied_binfo (primary, base_binfo);
1352 if (BINFO_PRIMARY_P (this_primary))
1353 /* Someone already claimed this base. */
1354 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1359 BINFO_PRIMARY_P (this_primary) = 1;
1360 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1362 /* A virtual binfo might have been copied from within
1363 another hierarchy. As we're about to use it as a
1364 primary base, make sure the offsets match. */
1365 delta = size_diffop (convert (ssizetype,
1366 BINFO_OFFSET (base_binfo)),
1368 BINFO_OFFSET (this_primary)));
1370 propagate_binfo_offsets (this_primary, delta);
1375 /* First look for a dynamic direct non-virtual base. */
1376 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1378 tree basetype = BINFO_TYPE (base_binfo);
1380 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1382 primary = base_binfo;
1387 /* A "nearly-empty" virtual base class can be the primary base
1388 class, if no non-virtual polymorphic base can be found. Look for
1389 a nearly-empty virtual dynamic base that is not already a primary
1390 base of something in the hierarchy. If there is no such base,
1391 just pick the first nearly-empty virtual base. */
1393 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1394 base_binfo = TREE_CHAIN (base_binfo))
1395 if (BINFO_VIRTUAL_P (base_binfo)
1396 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1398 if (!BINFO_PRIMARY_P (base_binfo))
1400 /* Found one that is not primary. */
1401 primary = base_binfo;
1405 /* Remember the first candidate. */
1406 primary = base_binfo;
1410 /* If we've got a primary base, use it. */
1413 tree basetype = BINFO_TYPE (primary);
1415 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1416 if (BINFO_PRIMARY_P (primary))
1417 /* We are stealing a primary base. */
1418 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1419 BINFO_PRIMARY_P (primary) = 1;
1420 if (BINFO_VIRTUAL_P (primary))
1424 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1425 /* A virtual binfo might have been copied from within
1426 another hierarchy. As we're about to use it as a primary
1427 base, make sure the offsets match. */
1428 delta = size_diffop (ssize_int (0),
1429 convert (ssizetype, BINFO_OFFSET (primary)));
1431 propagate_binfo_offsets (primary, delta);
1434 primary = TYPE_BINFO (basetype);
1436 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1437 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1438 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1442 /* Update the variant types of T. */
1445 fixup_type_variants (tree t)
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);
1478 /* Set memoizing fields and bits of T (and its variants) for later
1482 finish_struct_bits (tree t)
1484 /* Fix up variants (if any). */
1485 fixup_type_variants (t);
1487 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1488 /* For a class w/o baseclasses, 'finish_struct' has set
1489 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1490 Similarly for a class whose base classes do not have vtables.
1491 When neither of these is true, we might have removed abstract
1492 virtuals (by providing a definition), added some (by declaring
1493 new ones), or redeclared ones from a base class. We need to
1494 recalculate what's really an abstract virtual at this point (by
1495 looking in the vtables). */
1496 get_pure_virtuals (t);
1498 /* If this type has a copy constructor or a destructor, force its
1499 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1500 nonzero. This will cause it to be passed by invisible reference
1501 and prevent it from being returned in a register. */
1502 if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1505 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1506 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1508 SET_TYPE_MODE (variants, BLKmode);
1509 TREE_ADDRESSABLE (variants) = 1;
1514 /* Issue warnings about T having private constructors, but no friends,
1517 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1518 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1519 non-private static member functions. */
1522 maybe_warn_about_overly_private_class (tree t)
1524 int has_member_fn = 0;
1525 int has_nonprivate_method = 0;
1528 if (!warn_ctor_dtor_privacy
1529 /* If the class has friends, those entities might create and
1530 access instances, so we should not warn. */
1531 || (CLASSTYPE_FRIEND_CLASSES (t)
1532 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1533 /* We will have warned when the template was declared; there's
1534 no need to warn on every instantiation. */
1535 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1536 /* There's no reason to even consider warning about this
1540 /* We only issue one warning, if more than one applies, because
1541 otherwise, on code like:
1544 // Oops - forgot `public:'
1550 we warn several times about essentially the same problem. */
1552 /* Check to see if all (non-constructor, non-destructor) member
1553 functions are private. (Since there are no friends or
1554 non-private statics, we can't ever call any of the private member
1556 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1557 /* We're not interested in compiler-generated methods; they don't
1558 provide any way to call private members. */
1559 if (!DECL_ARTIFICIAL (fn))
1561 if (!TREE_PRIVATE (fn))
1563 if (DECL_STATIC_FUNCTION_P (fn))
1564 /* A non-private static member function is just like a
1565 friend; it can create and invoke private member
1566 functions, and be accessed without a class
1570 has_nonprivate_method = 1;
1571 /* Keep searching for a static member function. */
1573 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1577 if (!has_nonprivate_method && has_member_fn)
1579 /* There are no non-private methods, and there's at least one
1580 private member function that isn't a constructor or
1581 destructor. (If all the private members are
1582 constructors/destructors we want to use the code below that
1583 issues error messages specifically referring to
1584 constructors/destructors.) */
1586 tree binfo = TYPE_BINFO (t);
1588 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1589 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1591 has_nonprivate_method = 1;
1594 if (!has_nonprivate_method)
1596 warning (OPT_Wctor_dtor_privacy,
1597 "all member functions in class %qT are private", t);
1602 /* Even if some of the member functions are non-private, the class
1603 won't be useful for much if all the constructors or destructors
1604 are private: such an object can never be created or destroyed. */
1605 fn = CLASSTYPE_DESTRUCTORS (t);
1606 if (fn && TREE_PRIVATE (fn))
1608 warning (OPT_Wctor_dtor_privacy,
1609 "%q#T only defines a private destructor and has no friends",
1614 /* Warn about classes that have private constructors and no friends. */
1615 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1616 /* Implicitly generated constructors are always public. */
1617 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1618 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1620 int nonprivate_ctor = 0;
1622 /* If a non-template class does not define a copy
1623 constructor, one is defined for it, enabling it to avoid
1624 this warning. For a template class, this does not
1625 happen, and so we would normally get a warning on:
1627 template <class T> class C { private: C(); };
1629 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1630 complete non-template or fully instantiated classes have this
1632 if (!TYPE_HAS_INIT_REF (t))
1633 nonprivate_ctor = 1;
1635 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1637 tree ctor = OVL_CURRENT (fn);
1638 /* Ideally, we wouldn't count copy constructors (or, in
1639 fact, any constructor that takes an argument of the
1640 class type as a parameter) because such things cannot
1641 be used to construct an instance of the class unless
1642 you already have one. But, for now at least, we're
1644 if (! TREE_PRIVATE (ctor))
1646 nonprivate_ctor = 1;
1651 if (nonprivate_ctor == 0)
1653 warning (OPT_Wctor_dtor_privacy,
1654 "%q#T only defines private constructors and has no friends",
1662 gt_pointer_operator new_value;
1666 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1669 method_name_cmp (const void* m1_p, const void* m2_p)
1671 const tree *const m1 = (const tree *) m1_p;
1672 const tree *const m2 = (const tree *) m2_p;
1674 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1676 if (*m1 == NULL_TREE)
1678 if (*m2 == NULL_TREE)
1680 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1685 /* This routine compares two fields like method_name_cmp but using the
1686 pointer operator in resort_field_decl_data. */
1689 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1691 const tree *const m1 = (const tree *) m1_p;
1692 const tree *const m2 = (const tree *) m2_p;
1693 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1695 if (*m1 == NULL_TREE)
1697 if (*m2 == NULL_TREE)
1700 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1701 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1702 resort_data.new_value (&d1, resort_data.cookie);
1703 resort_data.new_value (&d2, resort_data.cookie);
1710 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1713 resort_type_method_vec (void* obj,
1714 void* orig_obj ATTRIBUTE_UNUSED ,
1715 gt_pointer_operator new_value,
1718 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1719 int len = VEC_length (tree, method_vec);
1723 /* The type conversion ops have to live at the front of the vec, so we
1725 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1726 VEC_iterate (tree, method_vec, slot, fn);
1728 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1733 resort_data.new_value = new_value;
1734 resort_data.cookie = cookie;
1735 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1736 resort_method_name_cmp);
1740 /* Warn about duplicate methods in fn_fields.
1742 Sort methods that are not special (i.e., constructors, destructors,
1743 and type conversion operators) so that we can find them faster in
1747 finish_struct_methods (tree t)
1750 VEC(tree,gc) *method_vec;
1753 method_vec = CLASSTYPE_METHOD_VEC (t);
1757 len = VEC_length (tree, method_vec);
1759 /* Clear DECL_IN_AGGR_P for all functions. */
1760 for (fn_fields = TYPE_METHODS (t); fn_fields;
1761 fn_fields = TREE_CHAIN (fn_fields))
1762 DECL_IN_AGGR_P (fn_fields) = 0;
1764 /* Issue warnings about private constructors and such. If there are
1765 no methods, then some public defaults are generated. */
1766 maybe_warn_about_overly_private_class (t);
1768 /* The type conversion ops have to live at the front of the vec, so we
1770 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1771 VEC_iterate (tree, method_vec, slot, fn_fields);
1773 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1776 qsort (VEC_address (tree, method_vec) + slot,
1777 len-slot, sizeof (tree), method_name_cmp);
1780 /* Make BINFO's vtable have N entries, including RTTI entries,
1781 vbase and vcall offsets, etc. Set its type and call the back end
1785 layout_vtable_decl (tree binfo, int n)
1790 atype = build_cplus_array_type (vtable_entry_type,
1791 build_index_type (size_int (n - 1)));
1792 layout_type (atype);
1794 /* We may have to grow the vtable. */
1795 vtable = get_vtbl_decl_for_binfo (binfo);
1796 if (!same_type_p (TREE_TYPE (vtable), atype))
1798 TREE_TYPE (vtable) = atype;
1799 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1800 layout_decl (vtable, 0);
1804 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1805 have the same signature. */
1808 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1810 /* One destructor overrides another if they are the same kind of
1812 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1813 && special_function_p (base_fndecl) == special_function_p (fndecl))
1815 /* But a non-destructor never overrides a destructor, nor vice
1816 versa, nor do different kinds of destructors override
1817 one-another. For example, a complete object destructor does not
1818 override a deleting destructor. */
1819 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1822 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1823 || (DECL_CONV_FN_P (fndecl)
1824 && DECL_CONV_FN_P (base_fndecl)
1825 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1826 DECL_CONV_FN_TYPE (base_fndecl))))
1828 tree types, base_types;
1829 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1830 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1831 if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1832 == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1833 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1839 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1843 base_derived_from (tree derived, tree base)
1847 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1849 if (probe == derived)
1851 else if (BINFO_VIRTUAL_P (probe))
1852 /* If we meet a virtual base, we can't follow the inheritance
1853 any more. See if the complete type of DERIVED contains
1854 such a virtual base. */
1855 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1861 typedef struct find_final_overrider_data_s {
1862 /* The function for which we are trying to find a final overrider. */
1864 /* The base class in which the function was declared. */
1865 tree declaring_base;
1866 /* The candidate overriders. */
1868 /* Path to most derived. */
1869 VEC(tree,heap) *path;
1870 } find_final_overrider_data;
1872 /* Add the overrider along the current path to FFOD->CANDIDATES.
1873 Returns true if an overrider was found; false otherwise. */
1876 dfs_find_final_overrider_1 (tree binfo,
1877 find_final_overrider_data *ffod,
1882 /* If BINFO is not the most derived type, try a more derived class.
1883 A definition there will overrider a definition here. */
1887 if (dfs_find_final_overrider_1
1888 (VEC_index (tree, ffod->path, depth), ffod, depth))
1892 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1895 tree *candidate = &ffod->candidates;
1897 /* Remove any candidates overridden by this new function. */
1900 /* If *CANDIDATE overrides METHOD, then METHOD
1901 cannot override anything else on the list. */
1902 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1904 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1905 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1906 *candidate = TREE_CHAIN (*candidate);
1908 candidate = &TREE_CHAIN (*candidate);
1911 /* Add the new function. */
1912 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1919 /* Called from find_final_overrider via dfs_walk. */
1922 dfs_find_final_overrider_pre (tree binfo, void *data)
1924 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1926 if (binfo == ffod->declaring_base)
1927 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1928 VEC_safe_push (tree, heap, ffod->path, binfo);
1934 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1936 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1937 VEC_pop (tree, ffod->path);
1942 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1943 FN and whose TREE_VALUE is the binfo for the base where the
1944 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1945 DERIVED) is the base object in which FN is declared. */
1948 find_final_overrider (tree derived, tree binfo, tree fn)
1950 find_final_overrider_data ffod;
1952 /* Getting this right is a little tricky. This is valid:
1954 struct S { virtual void f (); };
1955 struct T { virtual void f (); };
1956 struct U : public S, public T { };
1958 even though calling `f' in `U' is ambiguous. But,
1960 struct R { virtual void f(); };
1961 struct S : virtual public R { virtual void f (); };
1962 struct T : virtual public R { virtual void f (); };
1963 struct U : public S, public T { };
1965 is not -- there's no way to decide whether to put `S::f' or
1966 `T::f' in the vtable for `R'.
1968 The solution is to look at all paths to BINFO. If we find
1969 different overriders along any two, then there is a problem. */
1970 if (DECL_THUNK_P (fn))
1971 fn = THUNK_TARGET (fn);
1973 /* Determine the depth of the hierarchy. */
1975 ffod.declaring_base = binfo;
1976 ffod.candidates = NULL_TREE;
1977 ffod.path = VEC_alloc (tree, heap, 30);
1979 dfs_walk_all (derived, dfs_find_final_overrider_pre,
1980 dfs_find_final_overrider_post, &ffod);
1982 VEC_free (tree, heap, ffod.path);
1984 /* If there was no winner, issue an error message. */
1985 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
1986 return error_mark_node;
1988 return ffod.candidates;
1991 /* Return the index of the vcall offset for FN when TYPE is used as a
1995 get_vcall_index (tree fn, tree type)
1997 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2001 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
2002 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2003 || same_signature_p (fn, p->purpose))
2006 /* There should always be an appropriate index. */
2010 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2011 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
2012 corresponding position in the BINFO_VIRTUALS list. */
2015 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2023 tree overrider_fn, overrider_target;
2024 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2025 tree over_return, base_return;
2028 /* Find the nearest primary base (possibly binfo itself) which defines
2029 this function; this is the class the caller will convert to when
2030 calling FN through BINFO. */
2031 for (b = binfo; ; b = get_primary_binfo (b))
2034 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2037 /* The nearest definition is from a lost primary. */
2038 if (BINFO_LOST_PRIMARY_P (b))
2043 /* Find the final overrider. */
2044 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2045 if (overrider == error_mark_node)
2047 error ("no unique final overrider for %qD in %qT", target_fn, t);
2050 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2052 /* Check for adjusting covariant return types. */
2053 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2054 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2056 if (POINTER_TYPE_P (over_return)
2057 && TREE_CODE (over_return) == TREE_CODE (base_return)
2058 && CLASS_TYPE_P (TREE_TYPE (over_return))
2059 && CLASS_TYPE_P (TREE_TYPE (base_return))
2060 /* If the overrider is invalid, don't even try. */
2061 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2063 /* If FN is a covariant thunk, we must figure out the adjustment
2064 to the final base FN was converting to. As OVERRIDER_TARGET might
2065 also be converting to the return type of FN, we have to
2066 combine the two conversions here. */
2067 tree fixed_offset, virtual_offset;
2069 over_return = TREE_TYPE (over_return);
2070 base_return = TREE_TYPE (base_return);
2072 if (DECL_THUNK_P (fn))
2074 gcc_assert (DECL_RESULT_THUNK_P (fn));
2075 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2076 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2079 fixed_offset = virtual_offset = NULL_TREE;
2082 /* Find the equivalent binfo within the return type of the
2083 overriding function. We will want the vbase offset from
2085 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2087 else if (!same_type_ignoring_top_level_qualifiers_p
2088 (over_return, base_return))
2090 /* There was no existing virtual thunk (which takes
2091 precedence). So find the binfo of the base function's
2092 return type within the overriding function's return type.
2093 We cannot call lookup base here, because we're inside a
2094 dfs_walk, and will therefore clobber the BINFO_MARKED
2095 flags. Fortunately we know the covariancy is valid (it
2096 has already been checked), so we can just iterate along
2097 the binfos, which have been chained in inheritance graph
2098 order. Of course it is lame that we have to repeat the
2099 search here anyway -- we should really be caching pieces
2100 of the vtable and avoiding this repeated work. */
2101 tree thunk_binfo, base_binfo;
2103 /* Find the base binfo within the overriding function's
2104 return type. We will always find a thunk_binfo, except
2105 when the covariancy is invalid (which we will have
2106 already diagnosed). */
2107 for (base_binfo = TYPE_BINFO (base_return),
2108 thunk_binfo = TYPE_BINFO (over_return);
2110 thunk_binfo = TREE_CHAIN (thunk_binfo))
2111 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2112 BINFO_TYPE (base_binfo)))
2115 /* See if virtual inheritance is involved. */
2116 for (virtual_offset = thunk_binfo;
2118 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2119 if (BINFO_VIRTUAL_P (virtual_offset))
2123 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2125 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2129 /* We convert via virtual base. Adjust the fixed
2130 offset to be from there. */
2131 offset = size_diffop
2133 (ssizetype, BINFO_OFFSET (virtual_offset)));
2136 /* There was an existing fixed offset, this must be
2137 from the base just converted to, and the base the
2138 FN was thunking to. */
2139 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2141 fixed_offset = offset;
2145 if (fixed_offset || virtual_offset)
2146 /* Replace the overriding function with a covariant thunk. We
2147 will emit the overriding function in its own slot as
2149 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2150 fixed_offset, virtual_offset);
2153 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2154 !DECL_THUNK_P (fn));
2156 /* Assume that we will produce a thunk that convert all the way to
2157 the final overrider, and not to an intermediate virtual base. */
2158 virtual_base = NULL_TREE;
2160 /* See if we can convert to an intermediate virtual base first, and then
2161 use the vcall offset located there to finish the conversion. */
2162 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2164 /* If we find the final overrider, then we can stop
2166 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2167 BINFO_TYPE (TREE_VALUE (overrider))))
2170 /* If we find a virtual base, and we haven't yet found the
2171 overrider, then there is a virtual base between the
2172 declaring base (first_defn) and the final overrider. */
2173 if (BINFO_VIRTUAL_P (b))
2180 if (overrider_fn != overrider_target && !virtual_base)
2182 /* The ABI specifies that a covariant thunk includes a mangling
2183 for a this pointer adjustment. This-adjusting thunks that
2184 override a function from a virtual base have a vcall
2185 adjustment. When the virtual base in question is a primary
2186 virtual base, we know the adjustments are zero, (and in the
2187 non-covariant case, we would not use the thunk).
2188 Unfortunately we didn't notice this could happen, when
2189 designing the ABI and so never mandated that such a covariant
2190 thunk should be emitted. Because we must use the ABI mandated
2191 name, we must continue searching from the binfo where we
2192 found the most recent definition of the function, towards the
2193 primary binfo which first introduced the function into the
2194 vtable. If that enters a virtual base, we must use a vcall
2195 this-adjusting thunk. Bleah! */
2196 tree probe = first_defn;
2198 while ((probe = get_primary_binfo (probe))
2199 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2200 if (BINFO_VIRTUAL_P (probe))
2201 virtual_base = probe;
2204 /* Even if we find a virtual base, the correct delta is
2205 between the overrider and the binfo we're building a vtable
2207 goto virtual_covariant;
2210 /* Compute the constant adjustment to the `this' pointer. The
2211 `this' pointer, when this function is called, will point at BINFO
2212 (or one of its primary bases, which are at the same offset). */
2214 /* The `this' pointer needs to be adjusted from the declaration to
2215 the nearest virtual base. */
2216 delta = size_diffop (convert (ssizetype, BINFO_OFFSET (virtual_base)),
2217 convert (ssizetype, BINFO_OFFSET (first_defn)));
2219 /* If the nearest definition is in a lost primary, we don't need an
2220 entry in our vtable. Except possibly in a constructor vtable,
2221 if we happen to get our primary back. In that case, the offset
2222 will be zero, as it will be a primary base. */
2223 delta = size_zero_node;
2225 /* The `this' pointer needs to be adjusted from pointing to
2226 BINFO to pointing at the base where the final overrider
2229 delta = size_diffop (convert (ssizetype,
2230 BINFO_OFFSET (TREE_VALUE (overrider))),
2231 convert (ssizetype, BINFO_OFFSET (binfo)));
2233 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2236 BV_VCALL_INDEX (*virtuals)
2237 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2239 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2242 /* Called from modify_all_vtables via dfs_walk. */
2245 dfs_modify_vtables (tree binfo, void* data)
2247 tree t = (tree) data;
2252 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2253 /* A base without a vtable needs no modification, and its bases
2254 are uninteresting. */
2255 return dfs_skip_bases;
2257 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2258 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2259 /* Don't do the primary vtable, if it's new. */
2262 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2263 /* There's no need to modify the vtable for a non-virtual primary
2264 base; we're not going to use that vtable anyhow. We do still
2265 need to do this for virtual primary bases, as they could become
2266 non-primary in a construction vtable. */
2269 make_new_vtable (t, binfo);
2271 /* Now, go through each of the virtual functions in the virtual
2272 function table for BINFO. Find the final overrider, and update
2273 the BINFO_VIRTUALS list appropriately. */
2274 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2275 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2277 ix++, virtuals = TREE_CHAIN (virtuals),
2278 old_virtuals = TREE_CHAIN (old_virtuals))
2279 update_vtable_entry_for_fn (t,
2281 BV_FN (old_virtuals),
2287 /* Update all of the primary and secondary vtables for T. Create new
2288 vtables as required, and initialize their RTTI information. Each
2289 of the functions in VIRTUALS is declared in T and may override a
2290 virtual function from a base class; find and modify the appropriate
2291 entries to point to the overriding functions. Returns a list, in
2292 declaration order, of the virtual functions that are declared in T,
2293 but do not appear in the primary base class vtable, and which
2294 should therefore be appended to the end of the vtable for T. */
2297 modify_all_vtables (tree t, tree virtuals)
2299 tree binfo = TYPE_BINFO (t);
2302 /* Update all of the vtables. */
2303 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2305 /* Add virtual functions not already in our primary vtable. These
2306 will be both those introduced by this class, and those overridden
2307 from secondary bases. It does not include virtuals merely
2308 inherited from secondary bases. */
2309 for (fnsp = &virtuals; *fnsp; )
2311 tree fn = TREE_VALUE (*fnsp);
2313 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2314 || DECL_VINDEX (fn) == error_mark_node)
2316 /* We don't need to adjust the `this' pointer when
2317 calling this function. */
2318 BV_DELTA (*fnsp) = integer_zero_node;
2319 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2321 /* This is a function not already in our vtable. Keep it. */
2322 fnsp = &TREE_CHAIN (*fnsp);
2325 /* We've already got an entry for this function. Skip it. */
2326 *fnsp = TREE_CHAIN (*fnsp);
2332 /* Get the base virtual function declarations in T that have the
2336 get_basefndecls (tree name, tree t)
2339 tree base_fndecls = NULL_TREE;
2340 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2343 /* Find virtual functions in T with the indicated NAME. */
2344 i = lookup_fnfields_1 (t, name);
2346 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2348 methods = OVL_NEXT (methods))
2350 tree method = OVL_CURRENT (methods);
2352 if (TREE_CODE (method) == FUNCTION_DECL
2353 && DECL_VINDEX (method))
2354 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2358 return base_fndecls;
2360 for (i = 0; i < n_baseclasses; i++)
2362 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2363 base_fndecls = chainon (get_basefndecls (name, basetype),
2367 return base_fndecls;
2370 /* If this declaration supersedes the declaration of
2371 a method declared virtual in the base class, then
2372 mark this field as being virtual as well. */
2375 check_for_override (tree decl, tree ctype)
2377 if (TREE_CODE (decl) == TEMPLATE_DECL)
2378 /* In [temp.mem] we have:
2380 A specialization of a member function template does not
2381 override a virtual function from a base class. */
2383 if ((DECL_DESTRUCTOR_P (decl)
2384 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2385 || DECL_CONV_FN_P (decl))
2386 && look_for_overrides (ctype, decl)
2387 && !DECL_STATIC_FUNCTION_P (decl))
2388 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2389 the error_mark_node so that we know it is an overriding
2391 DECL_VINDEX (decl) = decl;
2393 if (DECL_VIRTUAL_P (decl))
2395 if (!DECL_VINDEX (decl))
2396 DECL_VINDEX (decl) = error_mark_node;
2397 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2401 /* Warn about hidden virtual functions that are not overridden in t.
2402 We know that constructors and destructors don't apply. */
2405 warn_hidden (tree t)
2407 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2411 /* We go through each separately named virtual function. */
2412 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2413 VEC_iterate (tree, method_vec, i, fns);
2424 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2425 have the same name. Figure out what name that is. */
2426 name = DECL_NAME (OVL_CURRENT (fns));
2427 /* There are no possibly hidden functions yet. */
2428 base_fndecls = NULL_TREE;
2429 /* Iterate through all of the base classes looking for possibly
2430 hidden functions. */
2431 for (binfo = TYPE_BINFO (t), j = 0;
2432 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2434 tree basetype = BINFO_TYPE (base_binfo);
2435 base_fndecls = chainon (get_basefndecls (name, basetype),
2439 /* If there are no functions to hide, continue. */
2443 /* Remove any overridden functions. */
2444 for (fn = fns; fn; fn = OVL_NEXT (fn))
2446 fndecl = OVL_CURRENT (fn);
2447 if (DECL_VINDEX (fndecl))
2449 tree *prev = &base_fndecls;
2452 /* If the method from the base class has the same
2453 signature as the method from the derived class, it
2454 has been overridden. */
2455 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2456 *prev = TREE_CHAIN (*prev);
2458 prev = &TREE_CHAIN (*prev);
2462 /* Now give a warning for all base functions without overriders,
2463 as they are hidden. */
2464 while (base_fndecls)
2466 /* Here we know it is a hider, and no overrider exists. */
2467 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2468 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2469 base_fndecls = TREE_CHAIN (base_fndecls);
2474 /* Check for things that are invalid. There are probably plenty of other
2475 things we should check for also. */
2478 finish_struct_anon (tree t)
2482 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2484 if (TREE_STATIC (field))
2486 if (TREE_CODE (field) != FIELD_DECL)
2489 if (DECL_NAME (field) == NULL_TREE
2490 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2492 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2493 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2494 for (; elt; elt = TREE_CHAIN (elt))
2496 /* We're generally only interested in entities the user
2497 declared, but we also find nested classes by noticing
2498 the TYPE_DECL that we create implicitly. You're
2499 allowed to put one anonymous union inside another,
2500 though, so we explicitly tolerate that. We use
2501 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2502 we also allow unnamed types used for defining fields. */
2503 if (DECL_ARTIFICIAL (elt)
2504 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2505 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2508 if (TREE_CODE (elt) != FIELD_DECL)
2511 permerror (input_location, "%q+#D invalid; an anonymous union can "
2512 "only have non-static data members", elt);
2514 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2515 "only have non-static data members", elt);
2519 if (TREE_PRIVATE (elt))
2522 permerror (input_location, "private member %q+#D in anonymous union", elt);
2524 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2526 else if (TREE_PROTECTED (elt))
2529 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2531 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2534 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2535 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2541 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2542 will be used later during class template instantiation.
2543 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2544 a non-static member data (FIELD_DECL), a member function
2545 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2546 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2547 When FRIEND_P is nonzero, T is either a friend class
2548 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2549 (FUNCTION_DECL, TEMPLATE_DECL). */
2552 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2554 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2555 if (CLASSTYPE_TEMPLATE_INFO (type))
2556 CLASSTYPE_DECL_LIST (type)
2557 = tree_cons (friend_p ? NULL_TREE : type,
2558 t, CLASSTYPE_DECL_LIST (type));
2561 /* Create default constructors, assignment operators, and so forth for
2562 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2563 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2564 the class cannot have a default constructor, copy constructor
2565 taking a const reference argument, or an assignment operator taking
2566 a const reference, respectively. */
2569 add_implicitly_declared_members (tree t,
2570 int cant_have_const_cctor,
2571 int cant_have_const_assignment)
2574 if (!CLASSTYPE_DESTRUCTORS (t))
2576 /* In general, we create destructors lazily. */
2577 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2578 /* However, if the implicit destructor is non-trivial
2579 destructor, we sometimes have to create it at this point. */
2580 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2584 if (TYPE_FOR_JAVA (t))
2585 /* If this a Java class, any non-trivial destructor is
2586 invalid, even if compiler-generated. Therefore, if the
2587 destructor is non-trivial we create it now. */
2595 /* If the implicit destructor will be virtual, then we must
2596 generate it now because (unfortunately) we do not
2597 generate virtual tables lazily. */
2598 binfo = TYPE_BINFO (t);
2599 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2604 base_type = BINFO_TYPE (base_binfo);
2605 dtor = CLASSTYPE_DESTRUCTORS (base_type);
2606 if (dtor && DECL_VIRTUAL_P (dtor))
2614 /* If we can't get away with being lazy, generate the destructor
2617 lazily_declare_fn (sfk_destructor, t);
2623 If there is no user-declared constructor for a class, a default
2624 constructor is implicitly declared. */
2625 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2627 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2628 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2633 If a class definition does not explicitly declare a copy
2634 constructor, one is declared implicitly. */
2635 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2637 TYPE_HAS_INIT_REF (t) = 1;
2638 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2639 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2642 /* If there is no assignment operator, one will be created if and
2643 when it is needed. For now, just record whether or not the type
2644 of the parameter to the assignment operator will be a const or
2645 non-const reference. */
2646 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2648 TYPE_HAS_ASSIGN_REF (t) = 1;
2649 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2650 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2654 /* Subroutine of finish_struct_1. Recursively count the number of fields
2655 in TYPE, including anonymous union members. */
2658 count_fields (tree fields)
2662 for (x = fields; x; x = TREE_CHAIN (x))
2664 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2665 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2672 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2673 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2676 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2679 for (x = fields; x; x = TREE_CHAIN (x))
2681 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2682 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2684 field_vec->elts[idx++] = x;
2689 /* FIELD is a bit-field. We are finishing the processing for its
2690 enclosing type. Issue any appropriate messages and set appropriate
2691 flags. Returns false if an error has been diagnosed. */
2694 check_bitfield_decl (tree field)
2696 tree type = TREE_TYPE (field);
2699 /* Extract the declared width of the bitfield, which has been
2700 temporarily stashed in DECL_INITIAL. */
2701 w = DECL_INITIAL (field);
2702 gcc_assert (w != NULL_TREE);
2703 /* Remove the bit-field width indicator so that the rest of the
2704 compiler does not treat that value as an initializer. */
2705 DECL_INITIAL (field) = NULL_TREE;
2707 /* Detect invalid bit-field type. */
2708 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2710 error ("bit-field %q+#D with non-integral type", field);
2711 w = error_mark_node;
2715 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2718 /* detect invalid field size. */
2719 w = integral_constant_value (w);
2721 if (TREE_CODE (w) != INTEGER_CST)
2723 error ("bit-field %q+D width not an integer constant", field);
2724 w = error_mark_node;
2726 else if (tree_int_cst_sgn (w) < 0)
2728 error ("negative width in bit-field %q+D", field);
2729 w = error_mark_node;
2731 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2733 error ("zero width for bit-field %q+D", field);
2734 w = error_mark_node;
2736 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2737 && TREE_CODE (type) != ENUMERAL_TYPE
2738 && TREE_CODE (type) != BOOLEAN_TYPE)
2739 warning (0, "width of %q+D exceeds its type", field);
2740 else if (TREE_CODE (type) == ENUMERAL_TYPE
2741 && (0 > compare_tree_int (w,
2742 tree_int_cst_min_precision
2743 (TYPE_MIN_VALUE (type),
2744 TYPE_UNSIGNED (type)))
2745 || 0 > compare_tree_int (w,
2746 tree_int_cst_min_precision
2747 (TYPE_MAX_VALUE (type),
2748 TYPE_UNSIGNED (type)))))
2749 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2752 if (w != error_mark_node)
2754 DECL_SIZE (field) = convert (bitsizetype, w);
2755 DECL_BIT_FIELD (field) = 1;
2760 /* Non-bit-fields are aligned for their type. */
2761 DECL_BIT_FIELD (field) = 0;
2762 CLEAR_DECL_C_BIT_FIELD (field);
2767 /* FIELD is a non bit-field. We are finishing the processing for its
2768 enclosing type T. Issue any appropriate messages and set appropriate
2772 check_field_decl (tree field,
2774 int* cant_have_const_ctor,
2775 int* no_const_asn_ref,
2776 int* any_default_members)
2778 tree type = strip_array_types (TREE_TYPE (field));
2780 /* An anonymous union cannot contain any fields which would change
2781 the settings of CANT_HAVE_CONST_CTOR and friends. */
2782 if (ANON_UNION_TYPE_P (type))
2784 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2785 structs. So, we recurse through their fields here. */
2786 else if (ANON_AGGR_TYPE_P (type))
2790 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2791 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2792 check_field_decl (fields, t, cant_have_const_ctor,
2793 no_const_asn_ref, any_default_members);
2795 /* Check members with class type for constructors, destructors,
2797 else if (CLASS_TYPE_P (type))
2799 /* Never let anything with uninheritable virtuals
2800 make it through without complaint. */
2801 abstract_virtuals_error (field, type);
2803 if (TREE_CODE (t) == UNION_TYPE)
2805 if (TYPE_NEEDS_CONSTRUCTING (type))
2806 error ("member %q+#D with constructor not allowed in union",
2808 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2809 error ("member %q+#D with destructor not allowed in union", field);
2810 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2811 error ("member %q+#D with copy assignment operator not allowed in union",
2816 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2817 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2818 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2819 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2820 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2821 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (type);
2824 if (!TYPE_HAS_CONST_INIT_REF (type))
2825 *cant_have_const_ctor = 1;
2827 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2828 *no_const_asn_ref = 1;
2830 if (DECL_INITIAL (field) != NULL_TREE)
2832 /* `build_class_init_list' does not recognize
2834 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2835 error ("multiple fields in union %qT initialized", t);
2836 *any_default_members = 1;
2840 /* Check the data members (both static and non-static), class-scoped
2841 typedefs, etc., appearing in the declaration of T. Issue
2842 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2843 declaration order) of access declarations; each TREE_VALUE in this
2844 list is a USING_DECL.
2846 In addition, set the following flags:
2849 The class is empty, i.e., contains no non-static data members.
2851 CANT_HAVE_CONST_CTOR_P
2852 This class cannot have an implicitly generated copy constructor
2853 taking a const reference.
2855 CANT_HAVE_CONST_ASN_REF
2856 This class cannot have an implicitly generated assignment
2857 operator taking a const reference.
2859 All of these flags should be initialized before calling this
2862 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2863 fields can be added by adding to this chain. */
2866 check_field_decls (tree t, tree *access_decls,
2867 int *cant_have_const_ctor_p,
2868 int *no_const_asn_ref_p)
2873 int any_default_members;
2876 /* Assume there are no access declarations. */
2877 *access_decls = NULL_TREE;
2878 /* Assume this class has no pointer members. */
2879 has_pointers = false;
2880 /* Assume none of the members of this class have default
2882 any_default_members = 0;
2884 for (field = &TYPE_FIELDS (t); *field; field = next)
2887 tree type = TREE_TYPE (x);
2889 next = &TREE_CHAIN (x);
2891 if (TREE_CODE (x) == USING_DECL)
2893 /* Prune the access declaration from the list of fields. */
2894 *field = TREE_CHAIN (x);
2896 /* Save the access declarations for our caller. */
2897 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2899 /* Since we've reset *FIELD there's no reason to skip to the
2905 if (TREE_CODE (x) == TYPE_DECL
2906 || TREE_CODE (x) == TEMPLATE_DECL)
2909 /* If we've gotten this far, it's a data member, possibly static,
2910 or an enumerator. */
2911 DECL_CONTEXT (x) = t;
2913 /* When this goes into scope, it will be a non-local reference. */
2914 DECL_NONLOCAL (x) = 1;
2916 if (TREE_CODE (t) == UNION_TYPE)
2920 If a union contains a static data member, or a member of
2921 reference type, the program is ill-formed. */
2922 if (TREE_CODE (x) == VAR_DECL)
2924 error ("%q+D may not be static because it is a member of a union", x);
2927 if (TREE_CODE (type) == REFERENCE_TYPE)
2929 error ("%q+D may not have reference type %qT because"
2930 " it is a member of a union",
2936 /* Perform error checking that did not get done in
2938 if (TREE_CODE (type) == FUNCTION_TYPE)
2940 error ("field %q+D invalidly declared function type", x);
2941 type = build_pointer_type (type);
2942 TREE_TYPE (x) = type;
2944 else if (TREE_CODE (type) == METHOD_TYPE)
2946 error ("field %q+D invalidly declared method type", x);
2947 type = build_pointer_type (type);
2948 TREE_TYPE (x) = type;
2951 if (type == error_mark_node)
2954 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
2957 /* Now it can only be a FIELD_DECL. */
2959 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
2960 CLASSTYPE_NON_AGGREGATE (t) = 1;
2962 /* If this is of reference type, check if it needs an init. */
2963 if (TREE_CODE (type) == REFERENCE_TYPE)
2965 CLASSTYPE_NON_POD_P (t) = 1;
2966 if (DECL_INITIAL (x) == NULL_TREE)
2967 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2969 /* ARM $12.6.2: [A member initializer list] (or, for an
2970 aggregate, initialization by a brace-enclosed list) is the
2971 only way to initialize nonstatic const and reference
2973 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2976 type = strip_array_types (type);
2978 if (TYPE_PACKED (t))
2980 if (!pod_type_p (type) && !TYPE_PACKED (type))
2984 "ignoring packed attribute because of unpacked non-POD field %q+#D",
2988 else if (DECL_C_BIT_FIELD (x)
2989 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
2990 DECL_PACKED (x) = 1;
2993 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
2994 /* We don't treat zero-width bitfields as making a class
2999 /* The class is non-empty. */
3000 CLASSTYPE_EMPTY_P (t) = 0;
3001 /* The class is not even nearly empty. */
3002 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3003 /* If one of the data members contains an empty class,
3005 if (CLASS_TYPE_P (type)
3006 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3007 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3010 /* This is used by -Weffc++ (see below). Warn only for pointers
3011 to members which might hold dynamic memory. So do not warn
3012 for pointers to functions or pointers to members. */
3013 if (TYPE_PTR_P (type)
3014 && !TYPE_PTRFN_P (type)
3015 && !TYPE_PTR_TO_MEMBER_P (type))
3016 has_pointers = true;
3018 if (CLASS_TYPE_P (type))
3020 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3021 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3022 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3023 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3026 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3027 CLASSTYPE_HAS_MUTABLE (t) = 1;
3029 if (! pod_type_p (type))
3030 /* DR 148 now allows pointers to members (which are POD themselves),
3031 to be allowed in POD structs. */
3032 CLASSTYPE_NON_POD_P (t) = 1;
3034 if (! zero_init_p (type))
3035 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3037 /* If any field is const, the structure type is pseudo-const. */
3038 if (CP_TYPE_CONST_P (type))
3040 C_TYPE_FIELDS_READONLY (t) = 1;
3041 if (DECL_INITIAL (x) == NULL_TREE)
3042 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3044 /* ARM $12.6.2: [A member initializer list] (or, for an
3045 aggregate, initialization by a brace-enclosed list) is the
3046 only way to initialize nonstatic const and reference
3048 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3050 /* A field that is pseudo-const makes the structure likewise. */
3051 else if (CLASS_TYPE_P (type))
3053 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3054 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3055 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3056 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3059 /* Core issue 80: A nonstatic data member is required to have a
3060 different name from the class iff the class has a
3061 user-declared constructor. */
3062 if (constructor_name_p (DECL_NAME (x), t)
3063 && TYPE_HAS_USER_CONSTRUCTOR (t))
3064 permerror (input_location, "field %q+#D with same name as class", x);
3066 /* We set DECL_C_BIT_FIELD in grokbitfield.
3067 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3068 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3069 check_field_decl (x, t,
3070 cant_have_const_ctor_p,
3072 &any_default_members);
3075 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3076 it should also define a copy constructor and an assignment operator to
3077 implement the correct copy semantic (deep vs shallow, etc.). As it is
3078 not feasible to check whether the constructors do allocate dynamic memory
3079 and store it within members, we approximate the warning like this:
3081 -- Warn only if there are members which are pointers
3082 -- Warn only if there is a non-trivial constructor (otherwise,
3083 there cannot be memory allocated).
3084 -- Warn only if there is a non-trivial destructor. We assume that the
3085 user at least implemented the cleanup correctly, and a destructor
3086 is needed to free dynamic memory.
3088 This seems enough for practical purposes. */
3091 && TYPE_HAS_USER_CONSTRUCTOR (t)
3092 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3093 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3095 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3097 if (! TYPE_HAS_INIT_REF (t))
3099 warning (OPT_Weffc__,
3100 " but does not override %<%T(const %T&)%>", t, t);
3101 if (!TYPE_HAS_ASSIGN_REF (t))
3102 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3104 else if (! TYPE_HAS_ASSIGN_REF (t))
3105 warning (OPT_Weffc__,
3106 " but does not override %<operator=(const %T&)%>", t);
3109 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3111 TYPE_PACKED (t) = 0;
3113 /* Check anonymous struct/anonymous union fields. */
3114 finish_struct_anon (t);
3116 /* We've built up the list of access declarations in reverse order.
3118 *access_decls = nreverse (*access_decls);
3121 /* If TYPE is an empty class type, records its OFFSET in the table of
3125 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3129 if (!is_empty_class (type))
3132 /* Record the location of this empty object in OFFSETS. */
3133 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3135 n = splay_tree_insert (offsets,
3136 (splay_tree_key) offset,
3137 (splay_tree_value) NULL_TREE);
3138 n->value = ((splay_tree_value)
3139 tree_cons (NULL_TREE,
3146 /* Returns nonzero if TYPE is an empty class type and there is
3147 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3150 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3155 if (!is_empty_class (type))
3158 /* Record the location of this empty object in OFFSETS. */
3159 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3163 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3164 if (same_type_p (TREE_VALUE (t), type))
3170 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3171 F for every subobject, passing it the type, offset, and table of
3172 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3175 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3176 than MAX_OFFSET will not be walked.
3178 If F returns a nonzero value, the traversal ceases, and that value
3179 is returned. Otherwise, returns zero. */
3182 walk_subobject_offsets (tree type,
3183 subobject_offset_fn f,
3190 tree type_binfo = NULL_TREE;
3192 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3194 if (max_offset && INT_CST_LT (max_offset, offset))
3197 if (type == error_mark_node)
3202 if (abi_version_at_least (2))
3204 type = BINFO_TYPE (type);
3207 if (CLASS_TYPE_P (type))
3213 /* Avoid recursing into objects that are not interesting. */
3214 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3217 /* Record the location of TYPE. */
3218 r = (*f) (type, offset, offsets);
3222 /* Iterate through the direct base classes of TYPE. */
3224 type_binfo = TYPE_BINFO (type);
3225 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3229 if (abi_version_at_least (2)
3230 && BINFO_VIRTUAL_P (binfo))
3234 && BINFO_VIRTUAL_P (binfo)
3235 && !BINFO_PRIMARY_P (binfo))
3238 if (!abi_version_at_least (2))
3239 binfo_offset = size_binop (PLUS_EXPR,
3241 BINFO_OFFSET (binfo));
3245 /* We cannot rely on BINFO_OFFSET being set for the base
3246 class yet, but the offsets for direct non-virtual
3247 bases can be calculated by going back to the TYPE. */
3248 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3249 binfo_offset = size_binop (PLUS_EXPR,
3251 BINFO_OFFSET (orig_binfo));
3254 r = walk_subobject_offsets (binfo,
3259 (abi_version_at_least (2)
3260 ? /*vbases_p=*/0 : vbases_p));
3265 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3268 VEC(tree,gc) *vbases;
3270 /* Iterate through the virtual base classes of TYPE. In G++
3271 3.2, we included virtual bases in the direct base class
3272 loop above, which results in incorrect results; the
3273 correct offsets for virtual bases are only known when
3274 working with the most derived type. */
3276 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3277 VEC_iterate (tree, vbases, ix, binfo); ix++)
3279 r = walk_subobject_offsets (binfo,
3281 size_binop (PLUS_EXPR,
3283 BINFO_OFFSET (binfo)),
3292 /* We still have to walk the primary base, if it is
3293 virtual. (If it is non-virtual, then it was walked
3295 tree vbase = get_primary_binfo (type_binfo);
3297 if (vbase && BINFO_VIRTUAL_P (vbase)
3298 && BINFO_PRIMARY_P (vbase)
3299 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3301 r = (walk_subobject_offsets
3303 offsets, max_offset, /*vbases_p=*/0));
3310 /* Iterate through the fields of TYPE. */
3311 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3312 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3316 if (abi_version_at_least (2))
3317 field_offset = byte_position (field);
3319 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3320 field_offset = DECL_FIELD_OFFSET (field);
3322 r = walk_subobject_offsets (TREE_TYPE (field),
3324 size_binop (PLUS_EXPR,
3334 else if (TREE_CODE (type) == ARRAY_TYPE)
3336 tree element_type = strip_array_types (type);
3337 tree domain = TYPE_DOMAIN (type);
3340 /* Avoid recursing into objects that are not interesting. */
3341 if (!CLASS_TYPE_P (element_type)
3342 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3345 /* Step through each of the elements in the array. */
3346 for (index = size_zero_node;
3347 /* G++ 3.2 had an off-by-one error here. */
3348 (abi_version_at_least (2)
3349 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3350 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3351 index = size_binop (PLUS_EXPR, index, size_one_node))
3353 r = walk_subobject_offsets (TREE_TYPE (type),
3361 offset = size_binop (PLUS_EXPR, offset,
3362 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3363 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3364 there's no point in iterating through the remaining
3365 elements of the array. */
3366 if (max_offset && INT_CST_LT (max_offset, offset))
3374 /* Record all of the empty subobjects of TYPE (either a type or a
3375 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3376 is being placed at OFFSET; otherwise, it is a base class that is
3377 being placed at OFFSET. */
3380 record_subobject_offsets (tree type,
3383 bool is_data_member)
3386 /* If recording subobjects for a non-static data member or a
3387 non-empty base class , we do not need to record offsets beyond
3388 the size of the biggest empty class. Additional data members
3389 will go at the end of the class. Additional base classes will go
3390 either at offset zero (if empty, in which case they cannot
3391 overlap with offsets past the size of the biggest empty class) or
3392 at the end of the class.
3394 However, if we are placing an empty base class, then we must record
3395 all offsets, as either the empty class is at offset zero (where
3396 other empty classes might later be placed) or at the end of the
3397 class (where other objects might then be placed, so other empty
3398 subobjects might later overlap). */
3400 || !is_empty_class (BINFO_TYPE (type)))
3401 max_offset = sizeof_biggest_empty_class;
3403 max_offset = NULL_TREE;
3404 walk_subobject_offsets (type, record_subobject_offset, offset,
3405 offsets, max_offset, is_data_member);
3408 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3409 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3410 virtual bases of TYPE are examined. */
3413 layout_conflict_p (tree type,
3418 splay_tree_node max_node;
3420 /* Get the node in OFFSETS that indicates the maximum offset where
3421 an empty subobject is located. */
3422 max_node = splay_tree_max (offsets);
3423 /* If there aren't any empty subobjects, then there's no point in
3424 performing this check. */
3428 return walk_subobject_offsets (type, check_subobject_offset, offset,
3429 offsets, (tree) (max_node->key),
3433 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3434 non-static data member of the type indicated by RLI. BINFO is the
3435 binfo corresponding to the base subobject, OFFSETS maps offsets to
3436 types already located at those offsets. This function determines
3437 the position of the DECL. */
3440 layout_nonempty_base_or_field (record_layout_info rli,
3445 tree offset = NULL_TREE;
3451 /* For the purposes of determining layout conflicts, we want to
3452 use the class type of BINFO; TREE_TYPE (DECL) will be the
3453 CLASSTYPE_AS_BASE version, which does not contain entries for
3454 zero-sized bases. */
3455 type = TREE_TYPE (binfo);
3460 type = TREE_TYPE (decl);
3464 /* Try to place the field. It may take more than one try if we have
3465 a hard time placing the field without putting two objects of the
3466 same type at the same address. */
3469 struct record_layout_info_s old_rli = *rli;
3471 /* Place this field. */
3472 place_field (rli, decl);
3473 offset = byte_position (decl);
3475 /* We have to check to see whether or not there is already
3476 something of the same type at the offset we're about to use.
3477 For example, consider:
3480 struct T : public S { int i; };
3481 struct U : public S, public T {};
3483 Here, we put S at offset zero in U. Then, we can't put T at
3484 offset zero -- its S component would be at the same address
3485 as the S we already allocated. So, we have to skip ahead.
3486 Since all data members, including those whose type is an
3487 empty class, have nonzero size, any overlap can happen only
3488 with a direct or indirect base-class -- it can't happen with
3490 /* In a union, overlap is permitted; all members are placed at
3492 if (TREE_CODE (rli->t) == UNION_TYPE)
3494 /* G++ 3.2 did not check for overlaps when placing a non-empty
3496 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3498 if (layout_conflict_p (field_p ? type : binfo, offset,
3501 /* Strip off the size allocated to this field. That puts us
3502 at the first place we could have put the field with
3503 proper alignment. */
3506 /* Bump up by the alignment required for the type. */
3508 = size_binop (PLUS_EXPR, rli->bitpos,
3510 ? CLASSTYPE_ALIGN (type)
3511 : TYPE_ALIGN (type)));
3512 normalize_rli (rli);
3515 /* There was no conflict. We're done laying out this field. */
3519 /* Now that we know where it will be placed, update its
3521 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3522 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3523 this point because their BINFO_OFFSET is copied from another
3524 hierarchy. Therefore, we may not need to add the entire
3526 propagate_binfo_offsets (binfo,
3527 size_diffop (convert (ssizetype, offset),
3529 BINFO_OFFSET (binfo))));
3532 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3535 empty_base_at_nonzero_offset_p (tree type,
3537 splay_tree offsets ATTRIBUTE_UNUSED)
3539 return is_empty_class (type) && !integer_zerop (offset);
3542 /* Layout the empty base BINFO. EOC indicates the byte currently just
3543 past the end of the class, and should be correctly aligned for a
3544 class of the type indicated by BINFO; OFFSETS gives the offsets of
3545 the empty bases allocated so far. T is the most derived
3546 type. Return nonzero iff we added it at the end. */
3549 layout_empty_base (record_layout_info rli, tree binfo,
3550 tree eoc, splay_tree offsets)
3553 tree basetype = BINFO_TYPE (binfo);
3556 /* This routine should only be used for empty classes. */
3557 gcc_assert (is_empty_class (basetype));
3558 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3560 if (!integer_zerop (BINFO_OFFSET (binfo)))
3562 if (abi_version_at_least (2))
3563 propagate_binfo_offsets
3564 (binfo, size_diffop (size_zero_node, BINFO_OFFSET (binfo)));
3567 "offset of empty base %qT may not be ABI-compliant and may"
3568 "change in a future version of GCC",
3569 BINFO_TYPE (binfo));
3572 /* This is an empty base class. We first try to put it at offset
3574 if (layout_conflict_p (binfo,
3575 BINFO_OFFSET (binfo),
3579 /* That didn't work. Now, we move forward from the next
3580 available spot in the class. */
3582 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3585 if (!layout_conflict_p (binfo,
3586 BINFO_OFFSET (binfo),
3589 /* We finally found a spot where there's no overlap. */
3592 /* There's overlap here, too. Bump along to the next spot. */
3593 propagate_binfo_offsets (binfo, alignment);
3597 if (CLASSTYPE_USER_ALIGN (basetype))
3599 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3601 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3602 TYPE_USER_ALIGN (rli->t) = 1;
3608 /* Layout the base given by BINFO in the class indicated by RLI.
3609 *BASE_ALIGN is a running maximum of the alignments of
3610 any base class. OFFSETS gives the location of empty base
3611 subobjects. T is the most derived type. Return nonzero if the new
3612 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3613 *NEXT_FIELD, unless BINFO is for an empty base class.
3615 Returns the location at which the next field should be inserted. */
3618 build_base_field (record_layout_info rli, tree binfo,
3619 splay_tree offsets, tree *next_field)
3622 tree basetype = BINFO_TYPE (binfo);
3624 if (!COMPLETE_TYPE_P (basetype))
3625 /* This error is now reported in xref_tag, thus giving better
3626 location information. */
3629 /* Place the base class. */
3630 if (!is_empty_class (basetype))
3634 /* The containing class is non-empty because it has a non-empty
3636 CLASSTYPE_EMPTY_P (t) = 0;
3638 /* Create the FIELD_DECL. */
3639 decl = build_decl (input_location,
3640 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3641 DECL_ARTIFICIAL (decl) = 1;
3642 DECL_IGNORED_P (decl) = 1;
3643 DECL_FIELD_CONTEXT (decl) = t;
3644 if (CLASSTYPE_AS_BASE (basetype))
3646 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3647 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3648 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3649 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3650 DECL_MODE (decl) = TYPE_MODE (basetype);
3651 DECL_FIELD_IS_BASE (decl) = 1;
3653 /* Try to place the field. It may take more than one try if we
3654 have a hard time placing the field without putting two
3655 objects of the same type at the same address. */
3656 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3657 /* Add the new FIELD_DECL to the list of fields for T. */
3658 TREE_CHAIN (decl) = *next_field;
3660 next_field = &TREE_CHAIN (decl);
3668 /* On some platforms (ARM), even empty classes will not be
3670 eoc = round_up (rli_size_unit_so_far (rli),
3671 CLASSTYPE_ALIGN_UNIT (basetype));
3672 atend = layout_empty_base (rli, binfo, eoc, offsets);
3673 /* A nearly-empty class "has no proper base class that is empty,
3674 not morally virtual, and at an offset other than zero." */
3675 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3678 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3679 /* The check above (used in G++ 3.2) is insufficient because
3680 an empty class placed at offset zero might itself have an
3681 empty base at a nonzero offset. */
3682 else if (walk_subobject_offsets (basetype,
3683 empty_base_at_nonzero_offset_p,
3686 /*max_offset=*/NULL_TREE,
3689 if (abi_version_at_least (2))
3690 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3693 "class %qT will be considered nearly empty in a "
3694 "future version of GCC", t);
3698 /* We do not create a FIELD_DECL for empty base classes because
3699 it might overlap some other field. We want to be able to
3700 create CONSTRUCTORs for the class by iterating over the
3701 FIELD_DECLs, and the back end does not handle overlapping
3704 /* An empty virtual base causes a class to be non-empty
3705 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3706 here because that was already done when the virtual table
3707 pointer was created. */
3710 /* Record the offsets of BINFO and its base subobjects. */
3711 record_subobject_offsets (binfo,
3712 BINFO_OFFSET (binfo),
3714 /*is_data_member=*/false);
3719 /* Layout all of the non-virtual base classes. Record empty
3720 subobjects in OFFSETS. T is the most derived type. Return nonzero
3721 if the type cannot be nearly empty. The fields created
3722 corresponding to the base classes will be inserted at
3726 build_base_fields (record_layout_info rli,
3727 splay_tree offsets, tree *next_field)
3729 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3732 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3735 /* The primary base class is always allocated first. */
3736 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3737 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3738 offsets, next_field);
3740 /* Now allocate the rest of the bases. */
3741 for (i = 0; i < n_baseclasses; ++i)
3745 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3747 /* The primary base was already allocated above, so we don't
3748 need to allocate it again here. */
3749 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3752 /* Virtual bases are added at the end (a primary virtual base
3753 will have already been added). */
3754 if (BINFO_VIRTUAL_P (base_binfo))
3757 next_field = build_base_field (rli, base_binfo,
3758 offsets, next_field);
3762 /* Go through the TYPE_METHODS of T issuing any appropriate
3763 diagnostics, figuring out which methods override which other
3764 methods, and so forth. */
3767 check_methods (tree t)
3771 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3773 check_for_override (x, t);
3774 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3775 error ("initializer specified for non-virtual method %q+D", x);
3776 /* The name of the field is the original field name
3777 Save this in auxiliary field for later overloading. */
3778 if (DECL_VINDEX (x))
3780 TYPE_POLYMORPHIC_P (t) = 1;
3781 if (DECL_PURE_VIRTUAL_P (x))
3782 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3784 /* All user-provided destructors are non-trivial. */
3785 if (DECL_DESTRUCTOR_P (x) && !DECL_DEFAULTED_FN (x))
3786 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3790 /* FN is a constructor or destructor. Clone the declaration to create
3791 a specialized in-charge or not-in-charge version, as indicated by
3795 build_clone (tree fn, tree name)
3800 /* Copy the function. */
3801 clone = copy_decl (fn);
3802 /* Remember where this function came from. */
3803 DECL_CLONED_FUNCTION (clone) = fn;
3804 DECL_ABSTRACT_ORIGIN (clone) = fn;
3805 /* Reset the function name. */
3806 DECL_NAME (clone) = name;
3807 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3808 /* There's no pending inline data for this function. */
3809 DECL_PENDING_INLINE_INFO (clone) = NULL;
3810 DECL_PENDING_INLINE_P (clone) = 0;
3811 /* And it hasn't yet been deferred. */
3812 DECL_DEFERRED_FN (clone) = 0;
3814 /* The base-class destructor is not virtual. */
3815 if (name == base_dtor_identifier)
3817 DECL_VIRTUAL_P (clone) = 0;
3818 if (TREE_CODE (clone) != TEMPLATE_DECL)
3819 DECL_VINDEX (clone) = NULL_TREE;
3822 /* If there was an in-charge parameter, drop it from the function
3824 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3830 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3831 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3832 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3833 /* Skip the `this' parameter. */
3834 parmtypes = TREE_CHAIN (parmtypes);
3835 /* Skip the in-charge parameter. */
3836 parmtypes = TREE_CHAIN (parmtypes);
3837 /* And the VTT parm, in a complete [cd]tor. */
3838 if (DECL_HAS_VTT_PARM_P (fn)
3839 && ! DECL_NEEDS_VTT_PARM_P (clone))
3840 parmtypes = TREE_CHAIN (parmtypes);
3841 /* If this is subobject constructor or destructor, add the vtt
3844 = build_method_type_directly (basetype,
3845 TREE_TYPE (TREE_TYPE (clone)),
3848 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3851 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3852 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3855 /* Copy the function parameters. But, DECL_ARGUMENTS on a TEMPLATE_DECL
3856 aren't function parameters; those are the template parameters. */
3857 if (TREE_CODE (clone) != TEMPLATE_DECL)
3859 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3860 /* Remove the in-charge parameter. */
3861 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3863 TREE_CHAIN (DECL_ARGUMENTS (clone))
3864 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3865 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3867 /* And the VTT parm, in a complete [cd]tor. */
3868 if (DECL_HAS_VTT_PARM_P (fn))
3870 if (DECL_NEEDS_VTT_PARM_P (clone))
3871 DECL_HAS_VTT_PARM_P (clone) = 1;
3874 TREE_CHAIN (DECL_ARGUMENTS (clone))
3875 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3876 DECL_HAS_VTT_PARM_P (clone) = 0;
3880 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3882 DECL_CONTEXT (parms) = clone;
3883 cxx_dup_lang_specific_decl (parms);
3887 /* Create the RTL for this function. */
3888 SET_DECL_RTL (clone, NULL_RTX);
3889 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3891 /* Make it easy to find the CLONE given the FN. */
3892 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3893 TREE_CHAIN (fn) = clone;
3895 /* If this is a template, handle the DECL_TEMPLATE_RESULT as well. */
3896 if (TREE_CODE (clone) == TEMPLATE_DECL)
3900 DECL_TEMPLATE_RESULT (clone)
3901 = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3902 result = DECL_TEMPLATE_RESULT (clone);
3903 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3904 DECL_TI_TEMPLATE (result) = clone;
3907 note_decl_for_pch (clone);
3912 /* Produce declarations for all appropriate clones of FN. If
3913 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
3914 CLASTYPE_METHOD_VEC as well. */
3917 clone_function_decl (tree fn, int update_method_vec_p)
3921 /* Avoid inappropriate cloning. */
3923 && DECL_CLONED_FUNCTION (TREE_CHAIN (fn)))
3926 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
3928 /* For each constructor, we need two variants: an in-charge version
3929 and a not-in-charge version. */
3930 clone = build_clone (fn, complete_ctor_identifier);
3931 if (update_method_vec_p)
3932 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3933 clone = build_clone (fn, base_ctor_identifier);
3934 if (update_method_vec_p)
3935 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3939 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
3941 /* For each destructor, we need three variants: an in-charge
3942 version, a not-in-charge version, and an in-charge deleting
3943 version. We clone the deleting version first because that
3944 means it will go second on the TYPE_METHODS list -- and that
3945 corresponds to the correct layout order in the virtual
3948 For a non-virtual destructor, we do not build a deleting
3950 if (DECL_VIRTUAL_P (fn))
3952 clone = build_clone (fn, deleting_dtor_identifier);
3953 if (update_method_vec_p)
3954 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3956 clone = build_clone (fn, complete_dtor_identifier);
3957 if (update_method_vec_p)
3958 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3959 clone = build_clone (fn, base_dtor_identifier);
3960 if (update_method_vec_p)
3961 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3964 /* Note that this is an abstract function that is never emitted. */
3965 DECL_ABSTRACT (fn) = 1;
3968 /* DECL is an in charge constructor, which is being defined. This will
3969 have had an in class declaration, from whence clones were
3970 declared. An out-of-class definition can specify additional default
3971 arguments. As it is the clones that are involved in overload
3972 resolution, we must propagate the information from the DECL to its
3976 adjust_clone_args (tree decl)
3980 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION (clone);
3981 clone = TREE_CHAIN (clone))
3983 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
3984 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
3985 tree decl_parms, clone_parms;
3987 clone_parms = orig_clone_parms;
3989 /* Skip the 'this' parameter. */
3990 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
3991 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3993 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
3994 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3995 if (DECL_HAS_VTT_PARM_P (decl))
3996 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3998 clone_parms = orig_clone_parms;
3999 if (DECL_HAS_VTT_PARM_P (clone))
4000 clone_parms = TREE_CHAIN (clone_parms);
4002 for (decl_parms = orig_decl_parms; decl_parms;
4003 decl_parms = TREE_CHAIN (decl_parms),
4004 clone_parms = TREE_CHAIN (clone_parms))
4006 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4007 TREE_TYPE (clone_parms)));
4009 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4011 /* A default parameter has been added. Adjust the
4012 clone's parameters. */
4013 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4014 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4017 clone_parms = orig_decl_parms;
4019 if (DECL_HAS_VTT_PARM_P (clone))
4021 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4022 TREE_VALUE (orig_clone_parms),
4024 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4026 type = build_method_type_directly (basetype,
4027 TREE_TYPE (TREE_TYPE (clone)),
4030 type = build_exception_variant (type, exceptions);
4031 TREE_TYPE (clone) = type;
4033 clone_parms = NULL_TREE;
4037 gcc_assert (!clone_parms);
4041 /* For each of the constructors and destructors in T, create an
4042 in-charge and not-in-charge variant. */
4045 clone_constructors_and_destructors (tree t)
4049 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4051 if (!CLASSTYPE_METHOD_VEC (t))
4054 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4055 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4056 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4057 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4060 /* Returns true iff class T has a user-defined constructor other than
4061 the default constructor. */
4064 type_has_user_nondefault_constructor (tree t)
4068 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4071 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4073 tree fn = OVL_CURRENT (fns);
4074 if (!DECL_ARTIFICIAL (fn)
4075 && (TREE_CODE (fn) == TEMPLATE_DECL
4076 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4084 /* Returns true iff FN is a user-provided function, i.e. user-declared
4085 and not defaulted at its first declaration. */
4088 user_provided_p (tree fn)
4090 if (TREE_CODE (fn) == TEMPLATE_DECL)
4093 return (!DECL_ARTIFICIAL (fn)
4094 && !(DECL_DEFAULTED_FN (fn)
4095 && DECL_INITIALIZED_IN_CLASS_P (fn)));
4098 /* Returns true iff class T has a user-provided constructor. */
4101 type_has_user_provided_constructor (tree t)
4105 if (!CLASS_TYPE_P (t))
4108 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4111 /* This can happen in error cases; avoid crashing. */
4112 if (!CLASSTYPE_METHOD_VEC (t))
4115 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4116 if (user_provided_p (OVL_CURRENT (fns)))
4122 /* Returns true iff class T has a user-provided default constructor. */
4125 type_has_user_provided_default_constructor (tree t)
4129 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4132 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4134 tree fn = OVL_CURRENT (fns);
4135 if (TREE_CODE (fn) == FUNCTION_DECL
4136 && user_provided_p (fn))
4138 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4139 while (args && TREE_PURPOSE (args))
4140 args = TREE_CHAIN (args);
4141 if (!args || args == void_list_node)
4149 /* Returns true if FN can be explicitly defaulted. */
4152 defaultable_fn_p (tree fn)
4154 if (DECL_CONSTRUCTOR_P (fn))
4156 if (FUNCTION_FIRST_USER_PARMTYPE (fn) == void_list_node)
4158 else if (copy_fn_p (fn) > 0
4159 && (TREE_CHAIN (FUNCTION_FIRST_USER_PARMTYPE (fn))
4165 else if (DECL_DESTRUCTOR_P (fn))
4167 else if (DECL_ASSIGNMENT_OPERATOR_P (fn)
4168 && DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR)
4169 return copy_fn_p (fn);
4174 /* Remove all zero-width bit-fields from T. */
4177 remove_zero_width_bit_fields (tree t)
4181 fieldsp = &TYPE_FIELDS (t);
4184 if (TREE_CODE (*fieldsp) == FIELD_DECL
4185 && DECL_C_BIT_FIELD (*fieldsp)
4186 && DECL_INITIAL (*fieldsp))
4187 *fieldsp = TREE_CHAIN (*fieldsp);
4189 fieldsp = &TREE_CHAIN (*fieldsp);
4193 /* Returns TRUE iff we need a cookie when dynamically allocating an
4194 array whose elements have the indicated class TYPE. */
4197 type_requires_array_cookie (tree type)
4200 bool has_two_argument_delete_p = false;
4202 gcc_assert (CLASS_TYPE_P (type));
4204 /* If there's a non-trivial destructor, we need a cookie. In order
4205 to iterate through the array calling the destructor for each
4206 element, we'll have to know how many elements there are. */
4207 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4210 /* If the usual deallocation function is a two-argument whose second
4211 argument is of type `size_t', then we have to pass the size of
4212 the array to the deallocation function, so we will need to store
4214 fns = lookup_fnfields (TYPE_BINFO (type),
4215 ansi_opname (VEC_DELETE_EXPR),
4217 /* If there are no `operator []' members, or the lookup is
4218 ambiguous, then we don't need a cookie. */
4219 if (!fns || fns == error_mark_node)
4221 /* Loop through all of the functions. */
4222 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4227 /* Select the current function. */
4228 fn = OVL_CURRENT (fns);
4229 /* See if this function is a one-argument delete function. If
4230 it is, then it will be the usual deallocation function. */
4231 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4232 if (second_parm == void_list_node)
4234 /* Do not consider this function if its second argument is an
4238 /* Otherwise, if we have a two-argument function and the second
4239 argument is `size_t', it will be the usual deallocation
4240 function -- unless there is one-argument function, too. */
4241 if (TREE_CHAIN (second_parm) == void_list_node
4242 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4243 has_two_argument_delete_p = true;
4246 return has_two_argument_delete_p;
4249 /* Check the validity of the bases and members declared in T. Add any
4250 implicitly-generated functions (like copy-constructors and
4251 assignment operators). Compute various flag bits (like
4252 CLASSTYPE_NON_POD_T) for T. This routine works purely at the C++
4253 level: i.e., independently of the ABI in use. */
4256 check_bases_and_members (tree t)
4258 /* Nonzero if the implicitly generated copy constructor should take
4259 a non-const reference argument. */
4260 int cant_have_const_ctor;
4261 /* Nonzero if the implicitly generated assignment operator
4262 should take a non-const reference argument. */
4263 int no_const_asn_ref;
4265 bool saved_complex_asn_ref;
4266 bool saved_nontrivial_dtor;
4268 /* By default, we use const reference arguments and generate default
4270 cant_have_const_ctor = 0;
4271 no_const_asn_ref = 0;
4273 /* Check all the base-classes. */
4274 check_bases (t, &cant_have_const_ctor,
4277 /* Check all the method declarations. */
4280 /* Save the initial values of these flags which only indicate whether
4281 or not the class has user-provided functions. As we analyze the
4282 bases and members we can set these flags for other reasons. */
4283 saved_complex_asn_ref = TYPE_HAS_COMPLEX_ASSIGN_REF (t);
4284 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4286 /* Check all the data member declarations. We cannot call
4287 check_field_decls until we have called check_bases check_methods,
4288 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4289 being set appropriately. */
4290 check_field_decls (t, &access_decls,
4291 &cant_have_const_ctor,
4294 /* A nearly-empty class has to be vptr-containing; a nearly empty
4295 class contains just a vptr. */
4296 if (!TYPE_CONTAINS_VPTR_P (t))
4297 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4299 /* Do some bookkeeping that will guide the generation of implicitly
4300 declared member functions. */
4301 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4302 /* We need to call a constructor for this class if it has a
4303 user-provided constructor, or if the default constructor is going
4304 to initialize the vptr. (This is not an if-and-only-if;
4305 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4306 themselves need constructing.) */
4307 TYPE_NEEDS_CONSTRUCTING (t)
4308 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4311 An aggregate is an array or a class with no user-provided
4312 constructors ... and no virtual functions.
4314 Again, other conditions for being an aggregate are checked
4316 CLASSTYPE_NON_AGGREGATE (t)
4317 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4318 CLASSTYPE_NON_POD_P (t)
4319 |= (CLASSTYPE_NON_AGGREGATE (t)
4320 || saved_nontrivial_dtor || saved_complex_asn_ref);
4321 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4322 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4324 /* If the class has no user-declared constructor, but does have
4325 non-static const or reference data members that can never be
4326 initialized, issue a warning. */
4327 if (warn_uninitialized
4328 /* Classes with user-declared constructors are presumed to
4329 initialize these members. */
4330 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4331 /* Aggregates can be initialized with brace-enclosed
4333 && CLASSTYPE_NON_AGGREGATE (t))
4337 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4341 if (TREE_CODE (field) != FIELD_DECL)
4344 type = TREE_TYPE (field);
4345 if (TREE_CODE (type) == REFERENCE_TYPE)
4346 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4347 "in class without a constructor", field);
4348 else if (CP_TYPE_CONST_P (type)
4349 && (!CLASS_TYPE_P (type)
4350 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4351 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4352 "in class without a constructor", field);
4356 /* Synthesize any needed methods. */
4357 add_implicitly_declared_members (t,
4358 cant_have_const_ctor,
4361 /* Create the in-charge and not-in-charge variants of constructors
4363 clone_constructors_and_destructors (t);
4365 /* Process the using-declarations. */
4366 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4367 handle_using_decl (TREE_VALUE (access_decls), t);
4369 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4370 finish_struct_methods (t);
4372 /* Figure out whether or not we will need a cookie when dynamically
4373 allocating an array of this type. */
4374 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4375 = type_requires_array_cookie (t);
4378 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4379 accordingly. If a new vfield was created (because T doesn't have a
4380 primary base class), then the newly created field is returned. It
4381 is not added to the TYPE_FIELDS list; it is the caller's
4382 responsibility to do that. Accumulate declared virtual functions
4386 create_vtable_ptr (tree t, tree* virtuals_p)
4390 /* Collect the virtual functions declared in T. */
4391 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4392 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4393 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4395 tree new_virtual = make_node (TREE_LIST);
4397 BV_FN (new_virtual) = fn;
4398 BV_DELTA (new_virtual) = integer_zero_node;
4399 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4401 TREE_CHAIN (new_virtual) = *virtuals_p;
4402 *virtuals_p = new_virtual;
4405 /* If we couldn't find an appropriate base class, create a new field
4406 here. Even if there weren't any new virtual functions, we might need a
4407 new virtual function table if we're supposed to include vptrs in
4408 all classes that need them. */
4409 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4411 /* We build this decl with vtbl_ptr_type_node, which is a
4412 `vtable_entry_type*'. It might seem more precise to use
4413 `vtable_entry_type (*)[N]' where N is the number of virtual
4414 functions. However, that would require the vtable pointer in
4415 base classes to have a different type than the vtable pointer
4416 in derived classes. We could make that happen, but that
4417 still wouldn't solve all the problems. In particular, the
4418 type-based alias analysis code would decide that assignments
4419 to the base class vtable pointer can't alias assignments to
4420 the derived class vtable pointer, since they have different
4421 types. Thus, in a derived class destructor, where the base
4422 class constructor was inlined, we could generate bad code for
4423 setting up the vtable pointer.
4425 Therefore, we use one type for all vtable pointers. We still
4426 use a type-correct type; it's just doesn't indicate the array
4427 bounds. That's better than using `void*' or some such; it's
4428 cleaner, and it let's the alias analysis code know that these
4429 stores cannot alias stores to void*! */
4432 field = build_decl (input_location,
4433 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4434 DECL_VIRTUAL_P (field) = 1;
4435 DECL_ARTIFICIAL (field) = 1;
4436 DECL_FIELD_CONTEXT (field) = t;
4437 DECL_FCONTEXT (field) = t;
4439 TYPE_VFIELD (t) = field;
4441 /* This class is non-empty. */
4442 CLASSTYPE_EMPTY_P (t) = 0;
4450 /* Fixup the inline function given by INFO now that the class is
4454 fixup_pending_inline (tree fn)
4456 if (DECL_PENDING_INLINE_INFO (fn))
4458 tree args = DECL_ARGUMENTS (fn);
4461 DECL_CONTEXT (args) = fn;
4462 args = TREE_CHAIN (args);
4467 /* Fixup the inline methods and friends in TYPE now that TYPE is
4471 fixup_inline_methods (tree type)
4473 tree method = TYPE_METHODS (type);
4474 VEC(tree,gc) *friends;
4477 if (method && TREE_CODE (method) == TREE_VEC)
4479 if (TREE_VEC_ELT (method, 1))
4480 method = TREE_VEC_ELT (method, 1);
4481 else if (TREE_VEC_ELT (method, 0))
4482 method = TREE_VEC_ELT (method, 0);
4484 method = TREE_VEC_ELT (method, 2);
4487 /* Do inline member functions. */
4488 for (; method; method = TREE_CHAIN (method))
4489 fixup_pending_inline (method);
4492 for (friends = CLASSTYPE_INLINE_FRIENDS (type), ix = 0;
4493 VEC_iterate (tree, friends, ix, method); ix++)
4494 fixup_pending_inline (method);
4495 CLASSTYPE_INLINE_FRIENDS (type) = NULL;
4498 /* Add OFFSET to all base types of BINFO which is a base in the
4499 hierarchy dominated by T.
4501 OFFSET, which is a type offset, is number of bytes. */
4504 propagate_binfo_offsets (tree binfo, tree offset)
4510 /* Update BINFO's offset. */
4511 BINFO_OFFSET (binfo)
4512 = convert (sizetype,
4513 size_binop (PLUS_EXPR,
4514 convert (ssizetype, BINFO_OFFSET (binfo)),
4517 /* Find the primary base class. */
4518 primary_binfo = get_primary_binfo (binfo);
4520 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4521 propagate_binfo_offsets (primary_binfo, offset);
4523 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4525 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4527 /* Don't do the primary base twice. */
4528 if (base_binfo == primary_binfo)
4531 if (BINFO_VIRTUAL_P (base_binfo))
4534 propagate_binfo_offsets (base_binfo, offset);
4538 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4539 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4540 empty subobjects of T. */
4543 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4547 bool first_vbase = true;
4550 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4553 if (!abi_version_at_least(2))
4555 /* In G++ 3.2, we incorrectly rounded the size before laying out
4556 the virtual bases. */
4557 finish_record_layout (rli, /*free_p=*/false);
4558 #ifdef STRUCTURE_SIZE_BOUNDARY
4559 /* Packed structures don't need to have minimum size. */
4560 if (! TYPE_PACKED (t))
4561 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4563 rli->offset = TYPE_SIZE_UNIT (t);
4564 rli->bitpos = bitsize_zero_node;
4565 rli->record_align = TYPE_ALIGN (t);
4568 /* Find the last field. The artificial fields created for virtual
4569 bases will go after the last extant field to date. */
4570 next_field = &TYPE_FIELDS (t);
4572 next_field = &TREE_CHAIN (*next_field);
4574 /* Go through the virtual bases, allocating space for each virtual
4575 base that is not already a primary base class. These are
4576 allocated in inheritance graph order. */
4577 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4579 if (!BINFO_VIRTUAL_P (vbase))
4582 if (!BINFO_PRIMARY_P (vbase))
4584 tree basetype = TREE_TYPE (vbase);
4586 /* This virtual base is not a primary base of any class in the
4587 hierarchy, so we have to add space for it. */
4588 next_field = build_base_field (rli, vbase,
4589 offsets, next_field);
4591 /* If the first virtual base might have been placed at a
4592 lower address, had we started from CLASSTYPE_SIZE, rather
4593 than TYPE_SIZE, issue a warning. There can be both false
4594 positives and false negatives from this warning in rare
4595 cases; to deal with all the possibilities would probably
4596 require performing both layout algorithms and comparing
4597 the results which is not particularly tractable. */
4601 (size_binop (CEIL_DIV_EXPR,
4602 round_up (CLASSTYPE_SIZE (t),
4603 CLASSTYPE_ALIGN (basetype)),
4605 BINFO_OFFSET (vbase))))
4607 "offset of virtual base %qT is not ABI-compliant and "
4608 "may change in a future version of GCC",
4611 first_vbase = false;
4616 /* Returns the offset of the byte just past the end of the base class
4620 end_of_base (tree binfo)
4624 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
4625 size = TYPE_SIZE_UNIT (char_type_node);
4626 else if (is_empty_class (BINFO_TYPE (binfo)))
4627 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4628 allocate some space for it. It cannot have virtual bases, so
4629 TYPE_SIZE_UNIT is fine. */
4630 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4632 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4634 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4637 /* Returns the offset of the byte just past the end of the base class
4638 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4639 only non-virtual bases are included. */
4642 end_of_class (tree t, int include_virtuals_p)
4644 tree result = size_zero_node;
4645 VEC(tree,gc) *vbases;
4651 for (binfo = TYPE_BINFO (t), i = 0;
4652 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4654 if (!include_virtuals_p
4655 && BINFO_VIRTUAL_P (base_binfo)
4656 && (!BINFO_PRIMARY_P (base_binfo)
4657 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4660 offset = end_of_base (base_binfo);
4661 if (INT_CST_LT_UNSIGNED (result, offset))
4665 /* G++ 3.2 did not check indirect virtual bases. */
4666 if (abi_version_at_least (2) && include_virtuals_p)
4667 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4668 VEC_iterate (tree, vbases, i, base_binfo); i++)
4670 offset = end_of_base (base_binfo);
4671 if (INT_CST_LT_UNSIGNED (result, offset))
4678 /* Warn about bases of T that are inaccessible because they are
4679 ambiguous. For example:
4682 struct T : public S {};
4683 struct U : public S, public T {};
4685 Here, `(S*) new U' is not allowed because there are two `S'
4689 warn_about_ambiguous_bases (tree t)
4692 VEC(tree,gc) *vbases;
4697 /* If there are no repeated bases, nothing can be ambiguous. */
4698 if (!CLASSTYPE_REPEATED_BASE_P (t))
4701 /* Check direct bases. */
4702 for (binfo = TYPE_BINFO (t), i = 0;
4703 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4705 basetype = BINFO_TYPE (base_binfo);
4707 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4708 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4712 /* Check for ambiguous virtual bases. */
4714 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4715 VEC_iterate (tree, vbases, i, binfo); i++)
4717 basetype = BINFO_TYPE (binfo);
4719 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4720 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4725 /* Compare two INTEGER_CSTs K1 and K2. */
4728 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4730 return tree_int_cst_compare ((tree) k1, (tree) k2);
4733 /* Increase the size indicated in RLI to account for empty classes
4734 that are "off the end" of the class. */
4737 include_empty_classes (record_layout_info rli)
4742 /* It might be the case that we grew the class to allocate a
4743 zero-sized base class. That won't be reflected in RLI, yet,
4744 because we are willing to overlay multiple bases at the same
4745 offset. However, now we need to make sure that RLI is big enough
4746 to reflect the entire class. */
4747 eoc = end_of_class (rli->t,
4748 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4749 rli_size = rli_size_unit_so_far (rli);
4750 if (TREE_CODE (rli_size) == INTEGER_CST
4751 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4753 if (!abi_version_at_least (2))
4754 /* In version 1 of the ABI, the size of a class that ends with
4755 a bitfield was not rounded up to a whole multiple of a
4756 byte. Because rli_size_unit_so_far returns only the number
4757 of fully allocated bytes, any extra bits were not included
4759 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4761 /* The size should have been rounded to a whole byte. */
4762 gcc_assert (tree_int_cst_equal
4763 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4765 = size_binop (PLUS_EXPR,
4767 size_binop (MULT_EXPR,
4768 convert (bitsizetype,
4769 size_binop (MINUS_EXPR,
4771 bitsize_int (BITS_PER_UNIT)));
4772 normalize_rli (rli);
4776 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4777 BINFO_OFFSETs for all of the base-classes. Position the vtable
4778 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4781 layout_class_type (tree t, tree *virtuals_p)
4783 tree non_static_data_members;
4786 record_layout_info rli;
4787 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4788 types that appear at that offset. */
4789 splay_tree empty_base_offsets;
4790 /* True if the last field layed out was a bit-field. */
4791 bool last_field_was_bitfield = false;
4792 /* The location at which the next field should be inserted. */
4794 /* T, as a base class. */
4797 /* Keep track of the first non-static data member. */
4798 non_static_data_members = TYPE_FIELDS (t);
4800 /* Start laying out the record. */
4801 rli = start_record_layout (t);
4803 /* Mark all the primary bases in the hierarchy. */
4804 determine_primary_bases (t);
4806 /* Create a pointer to our virtual function table. */
4807 vptr = create_vtable_ptr (t, virtuals_p);
4809 /* The vptr is always the first thing in the class. */
4812 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4813 TYPE_FIELDS (t) = vptr;
4814 next_field = &TREE_CHAIN (vptr);
4815 place_field (rli, vptr);
4818 next_field = &TYPE_FIELDS (t);
4820 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4821 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4823 build_base_fields (rli, empty_base_offsets, next_field);
4825 /* Layout the non-static data members. */
4826 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4831 /* We still pass things that aren't non-static data members to
4832 the back end, in case it wants to do something with them. */
4833 if (TREE_CODE (field) != FIELD_DECL)
4835 place_field (rli, field);
4836 /* If the static data member has incomplete type, keep track
4837 of it so that it can be completed later. (The handling
4838 of pending statics in finish_record_layout is
4839 insufficient; consider:
4842 struct S2 { static S1 s1; };
4844 At this point, finish_record_layout will be called, but
4845 S1 is still incomplete.) */
4846 if (TREE_CODE (field) == VAR_DECL)
4848 maybe_register_incomplete_var (field);
4849 /* The visibility of static data members is determined
4850 at their point of declaration, not their point of
4852 determine_visibility (field);
4857 type = TREE_TYPE (field);
4858 if (type == error_mark_node)
4861 padding = NULL_TREE;
4863 /* If this field is a bit-field whose width is greater than its
4864 type, then there are some special rules for allocating
4866 if (DECL_C_BIT_FIELD (field)
4867 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4871 bool was_unnamed_p = false;
4872 /* We must allocate the bits as if suitably aligned for the
4873 longest integer type that fits in this many bits. type
4874 of the field. Then, we are supposed to use the left over
4875 bits as additional padding. */
4876 for (itk = itk_char; itk != itk_none; ++itk)
4877 if (INT_CST_LT (DECL_SIZE (field),
4878 TYPE_SIZE (integer_types[itk])))
4881 /* ITK now indicates a type that is too large for the
4882 field. We have to back up by one to find the largest
4884 integer_type = integer_types[itk - 1];
4886 /* Figure out how much additional padding is required. GCC
4887 3.2 always created a padding field, even if it had zero
4889 if (!abi_version_at_least (2)
4890 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4892 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4893 /* In a union, the padding field must have the full width
4894 of the bit-field; all fields start at offset zero. */
4895 padding = DECL_SIZE (field);
4898 if (TREE_CODE (t) == UNION_TYPE)
4899 warning (OPT_Wabi, "size assigned to %qT may not be "
4900 "ABI-compliant and may change in a future "
4903 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4904 TYPE_SIZE (integer_type));
4907 #ifdef PCC_BITFIELD_TYPE_MATTERS
4908 /* An unnamed bitfield does not normally affect the
4909 alignment of the containing class on a target where
4910 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4911 make any exceptions for unnamed bitfields when the
4912 bitfields are longer than their types. Therefore, we
4913 temporarily give the field a name. */
4914 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4916 was_unnamed_p = true;
4917 DECL_NAME (field) = make_anon_name ();
4920 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4921 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4922 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4923 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4924 empty_base_offsets);
4926 DECL_NAME (field) = NULL_TREE;
4927 /* Now that layout has been performed, set the size of the
4928 field to the size of its declared type; the rest of the
4929 field is effectively invisible. */
4930 DECL_SIZE (field) = TYPE_SIZE (type);
4931 /* We must also reset the DECL_MODE of the field. */
4932 if (abi_version_at_least (2))
4933 DECL_MODE (field) = TYPE_MODE (type);
4935 && DECL_MODE (field) != TYPE_MODE (type))
4936 /* Versions of G++ before G++ 3.4 did not reset the
4939 "the offset of %qD may not be ABI-compliant and may "
4940 "change in a future version of GCC", field);
4943 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4944 empty_base_offsets);
4946 /* Remember the location of any empty classes in FIELD. */
4947 if (abi_version_at_least (2))
4948 record_subobject_offsets (TREE_TYPE (field),
4949 byte_position(field),
4951 /*is_data_member=*/true);
4953 /* If a bit-field does not immediately follow another bit-field,
4954 and yet it starts in the middle of a byte, we have failed to
4955 comply with the ABI. */
4957 && DECL_C_BIT_FIELD (field)
4958 /* The TREE_NO_WARNING flag gets set by Objective-C when
4959 laying out an Objective-C class. The ObjC ABI differs
4960 from the C++ ABI, and so we do not want a warning
4962 && !TREE_NO_WARNING (field)
4963 && !last_field_was_bitfield
4964 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
4965 DECL_FIELD_BIT_OFFSET (field),
4966 bitsize_unit_node)))
4967 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
4968 "change in a future version of GCC", field);
4970 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
4971 offset of the field. */
4973 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
4974 byte_position (field))
4975 && contains_empty_class_p (TREE_TYPE (field)))
4976 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
4977 "classes to be placed at different locations in a "
4978 "future version of GCC", field);
4980 /* The middle end uses the type of expressions to determine the
4981 possible range of expression values. In order to optimize
4982 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
4983 must be made aware of the width of "i", via its type.
4985 Because C++ does not have integer types of arbitrary width,
4986 we must (for the purposes of the front end) convert from the
4987 type assigned here to the declared type of the bitfield
4988 whenever a bitfield expression is used as an rvalue.
4989 Similarly, when assigning a value to a bitfield, the value
4990 must be converted to the type given the bitfield here. */
4991 if (DECL_C_BIT_FIELD (field))
4993 unsigned HOST_WIDE_INT width;
4994 tree ftype = TREE_TYPE (field);
4995 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
4996 if (width != TYPE_PRECISION (ftype))
4999 = c_build_bitfield_integer_type (width,
5000 TYPE_UNSIGNED (ftype));
5002 = cp_build_qualified_type (TREE_TYPE (field),
5003 TYPE_QUALS (ftype));
5007 /* If we needed additional padding after this field, add it
5013 padding_field = build_decl (input_location,
5017 DECL_BIT_FIELD (padding_field) = 1;
5018 DECL_SIZE (padding_field) = padding;
5019 DECL_CONTEXT (padding_field) = t;
5020 DECL_ARTIFICIAL (padding_field) = 1;
5021 DECL_IGNORED_P (padding_field) = 1;
5022 layout_nonempty_base_or_field (rli, padding_field,
5024 empty_base_offsets);
5027 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5030 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5032 /* Make sure that we are on a byte boundary so that the size of
5033 the class without virtual bases will always be a round number
5035 rli->bitpos = round_up (rli->bitpos, BITS_PER_UNIT);
5036 normalize_rli (rli);
5039 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5041 if (!abi_version_at_least (2))
5042 include_empty_classes(rli);
5044 /* Delete all zero-width bit-fields from the list of fields. Now
5045 that the type is laid out they are no longer important. */
5046 remove_zero_width_bit_fields (t);
5048 /* Create the version of T used for virtual bases. We do not use
5049 make_class_type for this version; this is an artificial type. For
5050 a POD type, we just reuse T. */
5051 if (CLASSTYPE_NON_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5053 base_t = make_node (TREE_CODE (t));
5055 /* Set the size and alignment for the new type. In G++ 3.2, all
5056 empty classes were considered to have size zero when used as
5058 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5060 TYPE_SIZE (base_t) = bitsize_zero_node;
5061 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5062 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5064 "layout of classes derived from empty class %qT "
5065 "may change in a future version of GCC",
5072 /* If the ABI version is not at least two, and the last
5073 field was a bit-field, RLI may not be on a byte
5074 boundary. In particular, rli_size_unit_so_far might
5075 indicate the last complete byte, while rli_size_so_far
5076 indicates the total number of bits used. Therefore,
5077 rli_size_so_far, rather than rli_size_unit_so_far, is
5078 used to compute TYPE_SIZE_UNIT. */
5079 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5080 TYPE_SIZE_UNIT (base_t)
5081 = size_binop (MAX_EXPR,
5083 size_binop (CEIL_DIV_EXPR,
5084 rli_size_so_far (rli),
5085 bitsize_int (BITS_PER_UNIT))),
5088 = size_binop (MAX_EXPR,
5089 rli_size_so_far (rli),
5090 size_binop (MULT_EXPR,
5091 convert (bitsizetype, eoc),
5092 bitsize_int (BITS_PER_UNIT)));
5094 TYPE_ALIGN (base_t) = rli->record_align;
5095 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5097 /* Copy the fields from T. */
5098 next_field = &TYPE_FIELDS (base_t);
5099 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5100 if (TREE_CODE (field) == FIELD_DECL)
5102 *next_field = build_decl (input_location,
5106 DECL_CONTEXT (*next_field) = base_t;
5107 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5108 DECL_FIELD_BIT_OFFSET (*next_field)
5109 = DECL_FIELD_BIT_OFFSET (field);
5110 DECL_SIZE (*next_field) = DECL_SIZE (field);
5111 DECL_MODE (*next_field) = DECL_MODE (field);
5112 next_field = &TREE_CHAIN (*next_field);
5115 /* Record the base version of the type. */
5116 CLASSTYPE_AS_BASE (t) = base_t;
5117 TYPE_CONTEXT (base_t) = t;
5120 CLASSTYPE_AS_BASE (t) = t;
5122 /* Every empty class contains an empty class. */
5123 if (CLASSTYPE_EMPTY_P (t))
5124 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5126 /* Set the TYPE_DECL for this type to contain the right
5127 value for DECL_OFFSET, so that we can use it as part
5128 of a COMPONENT_REF for multiple inheritance. */
5129 layout_decl (TYPE_MAIN_DECL (t), 0);
5131 /* Now fix up any virtual base class types that we left lying
5132 around. We must get these done before we try to lay out the
5133 virtual function table. As a side-effect, this will remove the
5134 base subobject fields. */
5135 layout_virtual_bases (rli, empty_base_offsets);
5137 /* Make sure that empty classes are reflected in RLI at this
5139 include_empty_classes(rli);
5141 /* Make sure not to create any structures with zero size. */
5142 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5144 build_decl (input_location,
5145 FIELD_DECL, NULL_TREE, char_type_node));
5147 /* Let the back end lay out the type. */
5148 finish_record_layout (rli, /*free_p=*/true);
5150 /* Warn about bases that can't be talked about due to ambiguity. */
5151 warn_about_ambiguous_bases (t);
5153 /* Now that we're done with layout, give the base fields the real types. */
5154 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5155 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5156 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5159 splay_tree_delete (empty_base_offsets);
5161 if (CLASSTYPE_EMPTY_P (t)
5162 && tree_int_cst_lt (sizeof_biggest_empty_class,
5163 TYPE_SIZE_UNIT (t)))
5164 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5167 /* Determine the "key method" for the class type indicated by TYPE,
5168 and set CLASSTYPE_KEY_METHOD accordingly. */
5171 determine_key_method (tree type)
5175 if (TYPE_FOR_JAVA (type)
5176 || processing_template_decl
5177 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5178 || CLASSTYPE_INTERFACE_KNOWN (type))
5181 /* The key method is the first non-pure virtual function that is not
5182 inline at the point of class definition. On some targets the
5183 key function may not be inline; those targets should not call
5184 this function until the end of the translation unit. */
5185 for (method = TYPE_METHODS (type); method != NULL_TREE;
5186 method = TREE_CHAIN (method))
5187 if (DECL_VINDEX (method) != NULL_TREE
5188 && ! DECL_DECLARED_INLINE_P (method)
5189 && ! DECL_PURE_VIRTUAL_P (method))
5191 CLASSTYPE_KEY_METHOD (type) = method;
5198 /* Perform processing required when the definition of T (a class type)
5202 finish_struct_1 (tree t)
5205 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5206 tree virtuals = NULL_TREE;
5209 if (COMPLETE_TYPE_P (t))
5211 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5212 error ("redefinition of %q#T", t);
5217 /* If this type was previously laid out as a forward reference,
5218 make sure we lay it out again. */
5219 TYPE_SIZE (t) = NULL_TREE;
5220 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5222 fixup_inline_methods (t);
5224 /* Make assumptions about the class; we'll reset the flags if
5226 CLASSTYPE_EMPTY_P (t) = 1;
5227 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5228 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5230 /* Do end-of-class semantic processing: checking the validity of the
5231 bases and members and add implicitly generated methods. */
5232 check_bases_and_members (t);
5234 /* Find the key method. */
5235 if (TYPE_CONTAINS_VPTR_P (t))
5237 /* The Itanium C++ ABI permits the key method to be chosen when
5238 the class is defined -- even though the key method so
5239 selected may later turn out to be an inline function. On
5240 some systems (such as ARM Symbian OS) the key method cannot
5241 be determined until the end of the translation unit. On such
5242 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5243 will cause the class to be added to KEYED_CLASSES. Then, in
5244 finish_file we will determine the key method. */
5245 if (targetm.cxx.key_method_may_be_inline ())
5246 determine_key_method (t);
5248 /* If a polymorphic class has no key method, we may emit the vtable
5249 in every translation unit where the class definition appears. */
5250 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5251 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5254 /* Layout the class itself. */
5255 layout_class_type (t, &virtuals);
5256 if (CLASSTYPE_AS_BASE (t) != t)
5257 /* We use the base type for trivial assignments, and hence it
5259 compute_record_mode (CLASSTYPE_AS_BASE (t));
5261 virtuals = modify_all_vtables (t, nreverse (virtuals));
5263 /* If necessary, create the primary vtable for this class. */
5264 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5266 /* We must enter these virtuals into the table. */
5267 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5268 build_primary_vtable (NULL_TREE, t);
5269 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5270 /* Here we know enough to change the type of our virtual
5271 function table, but we will wait until later this function. */
5272 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5275 if (TYPE_CONTAINS_VPTR_P (t))
5280 if (BINFO_VTABLE (TYPE_BINFO (t)))
5281 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5282 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5283 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5285 /* Add entries for virtual functions introduced by this class. */
5286 BINFO_VIRTUALS (TYPE_BINFO (t))
5287 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5289 /* Set DECL_VINDEX for all functions declared in this class. */
5290 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5292 fn = TREE_CHAIN (fn),
5293 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5294 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5296 tree fndecl = BV_FN (fn);
5298 if (DECL_THUNK_P (fndecl))
5299 /* A thunk. We should never be calling this entry directly
5300 from this vtable -- we'd use the entry for the non
5301 thunk base function. */
5302 DECL_VINDEX (fndecl) = NULL_TREE;
5303 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5304 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5308 finish_struct_bits (t);
5310 /* Complete the rtl for any static member objects of the type we're
5312 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5313 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5314 && TREE_TYPE (x) != error_mark_node
5315 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5316 DECL_MODE (x) = TYPE_MODE (t);
5318 /* Done with FIELDS...now decide whether to sort these for
5319 faster lookups later.
5321 We use a small number because most searches fail (succeeding
5322 ultimately as the search bores through the inheritance
5323 hierarchy), and we want this failure to occur quickly. */
5325 n_fields = count_fields (TYPE_FIELDS (t));
5328 struct sorted_fields_type *field_vec = GGC_NEWVAR
5329 (struct sorted_fields_type,
5330 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5331 field_vec->len = n_fields;
5332 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5333 qsort (field_vec->elts, n_fields, sizeof (tree),
5335 if (! DECL_LANG_SPECIFIC (TYPE_MAIN_DECL (t)))
5336 retrofit_lang_decl (TYPE_MAIN_DECL (t));
5337 DECL_SORTED_FIELDS (TYPE_MAIN_DECL (t)) = field_vec;
5340 /* Complain if one of the field types requires lower visibility. */
5341 constrain_class_visibility (t);
5343 /* Make the rtl for any new vtables we have created, and unmark
5344 the base types we marked. */
5347 /* Build the VTT for T. */
5350 /* This warning does not make sense for Java classes, since they
5351 cannot have destructors. */
5352 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5356 dtor = CLASSTYPE_DESTRUCTORS (t);
5357 if (/* An implicitly declared destructor is always public. And,
5358 if it were virtual, we would have created it by now. */
5360 || (!DECL_VINDEX (dtor)
5361 && (/* public non-virtual */
5362 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5363 || (/* non-public non-virtual with friends */
5364 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5365 && (CLASSTYPE_FRIEND_CLASSES (t)
5366 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5367 warning (OPT_Wnon_virtual_dtor,
5368 "%q#T has virtual functions and accessible"
5369 " non-virtual destructor", t);
5374 if (warn_overloaded_virtual)
5377 /* Class layout, assignment of virtual table slots, etc., is now
5378 complete. Give the back end a chance to tweak the visibility of
5379 the class or perform any other required target modifications. */
5380 targetm.cxx.adjust_class_at_definition (t);
5382 maybe_suppress_debug_info (t);
5384 dump_class_hierarchy (t);
5386 /* Finish debugging output for this type. */
5387 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5390 /* When T was built up, the member declarations were added in reverse
5391 order. Rearrange them to declaration order. */
5394 unreverse_member_declarations (tree t)
5400 /* The following lists are all in reverse order. Put them in
5401 declaration order now. */
5402 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5403 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5405 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5406 reverse order, so we can't just use nreverse. */
5408 for (x = TYPE_FIELDS (t);
5409 x && TREE_CODE (x) != TYPE_DECL;
5412 next = TREE_CHAIN (x);
5413 TREE_CHAIN (x) = prev;
5418 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5420 TYPE_FIELDS (t) = prev;
5425 finish_struct (tree t, tree attributes)
5427 location_t saved_loc = input_location;
5429 /* Now that we've got all the field declarations, reverse everything
5431 unreverse_member_declarations (t);
5433 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5435 /* Nadger the current location so that diagnostics point to the start of
5436 the struct, not the end. */
5437 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5439 if (processing_template_decl)
5443 finish_struct_methods (t);
5444 TYPE_SIZE (t) = bitsize_zero_node;
5445 TYPE_SIZE_UNIT (t) = size_zero_node;
5447 /* We need to emit an error message if this type was used as a parameter
5448 and it is an abstract type, even if it is a template. We construct
5449 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5450 account and we call complete_vars with this type, which will check
5451 the PARM_DECLS. Note that while the type is being defined,
5452 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5453 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5454 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5455 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5456 if (DECL_PURE_VIRTUAL_P (x))
5457 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5461 finish_struct_1 (t);
5463 input_location = saved_loc;
5465 TYPE_BEING_DEFINED (t) = 0;
5467 if (current_class_type)
5470 error ("trying to finish struct, but kicked out due to previous parse errors");
5472 if (processing_template_decl && at_function_scope_p ())
5473 add_stmt (build_min (TAG_DEFN, t));
5478 /* Return the dynamic type of INSTANCE, if known.
5479 Used to determine whether the virtual function table is needed
5482 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5483 of our knowledge of its type. *NONNULL should be initialized
5484 before this function is called. */
5487 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5489 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5491 switch (TREE_CODE (instance))
5494 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5497 return RECUR (TREE_OPERAND (instance, 0));
5500 /* This is a call to a constructor, hence it's never zero. */
5501 if (TREE_HAS_CONSTRUCTOR (instance))
5505 return TREE_TYPE (instance);
5510 /* This is a call to a constructor, hence it's never zero. */
5511 if (TREE_HAS_CONSTRUCTOR (instance))
5515 return TREE_TYPE (instance);
5517 return RECUR (TREE_OPERAND (instance, 0));
5519 case POINTER_PLUS_EXPR:
5522 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5523 return RECUR (TREE_OPERAND (instance, 0));
5524 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5525 /* Propagate nonnull. */
5526 return RECUR (TREE_OPERAND (instance, 0));
5531 return RECUR (TREE_OPERAND (instance, 0));
5534 instance = TREE_OPERAND (instance, 0);
5537 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5538 with a real object -- given &p->f, p can still be null. */
5539 tree t = get_base_address (instance);
5540 /* ??? Probably should check DECL_WEAK here. */
5541 if (t && DECL_P (t))
5544 return RECUR (instance);
5547 /* If this component is really a base class reference, then the field
5548 itself isn't definitive. */
5549 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5550 return RECUR (TREE_OPERAND (instance, 0));
5551 return RECUR (TREE_OPERAND (instance, 1));
5555 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5556 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
5560 return TREE_TYPE (TREE_TYPE (instance));
5562 /* fall through... */
5566 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
5570 return TREE_TYPE (instance);
5572 else if (instance == current_class_ptr)
5577 /* if we're in a ctor or dtor, we know our type. */
5578 if (DECL_LANG_SPECIFIC (current_function_decl)
5579 && (DECL_CONSTRUCTOR_P (current_function_decl)
5580 || DECL_DESTRUCTOR_P (current_function_decl)))
5584 return TREE_TYPE (TREE_TYPE (instance));
5587 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5589 /* We only need one hash table because it is always left empty. */
5592 ht = htab_create (37,
5597 /* Reference variables should be references to objects. */
5601 /* Enter the INSTANCE in a table to prevent recursion; a
5602 variable's initializer may refer to the variable
5604 if (TREE_CODE (instance) == VAR_DECL
5605 && DECL_INITIAL (instance)
5606 && !htab_find (ht, instance))
5611 slot = htab_find_slot (ht, instance, INSERT);
5613 type = RECUR (DECL_INITIAL (instance));
5614 htab_remove_elt (ht, instance);
5627 /* Return nonzero if the dynamic type of INSTANCE is known, and
5628 equivalent to the static type. We also handle the case where
5629 INSTANCE is really a pointer. Return negative if this is a
5630 ctor/dtor. There the dynamic type is known, but this might not be
5631 the most derived base of the original object, and hence virtual
5632 bases may not be layed out according to this type.
5634 Used to determine whether the virtual function table is needed
5637 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5638 of our knowledge of its type. *NONNULL should be initialized
5639 before this function is called. */
5642 resolves_to_fixed_type_p (tree instance, int* nonnull)
5644 tree t = TREE_TYPE (instance);
5646 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5647 if (fixed == NULL_TREE)
5649 if (POINTER_TYPE_P (t))
5651 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5653 return cdtorp ? -1 : 1;
5658 init_class_processing (void)
5660 current_class_depth = 0;
5661 current_class_stack_size = 10;
5663 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5664 local_classes = VEC_alloc (tree, gc, 8);
5665 sizeof_biggest_empty_class = size_zero_node;
5667 ridpointers[(int) RID_PUBLIC] = access_public_node;
5668 ridpointers[(int) RID_PRIVATE] = access_private_node;
5669 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5672 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5675 restore_class_cache (void)
5679 /* We are re-entering the same class we just left, so we don't
5680 have to search the whole inheritance matrix to find all the
5681 decls to bind again. Instead, we install the cached
5682 class_shadowed list and walk through it binding names. */
5683 push_binding_level (previous_class_level);
5684 class_binding_level = previous_class_level;
5685 /* Restore IDENTIFIER_TYPE_VALUE. */
5686 for (type = class_binding_level->type_shadowed;
5688 type = TREE_CHAIN (type))
5689 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5692 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5693 appropriate for TYPE.
5695 So that we may avoid calls to lookup_name, we cache the _TYPE
5696 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5698 For multiple inheritance, we perform a two-pass depth-first search
5699 of the type lattice. */
5702 pushclass (tree type)
5704 class_stack_node_t csn;
5706 type = TYPE_MAIN_VARIANT (type);
5708 /* Make sure there is enough room for the new entry on the stack. */
5709 if (current_class_depth + 1 >= current_class_stack_size)
5711 current_class_stack_size *= 2;
5713 = XRESIZEVEC (struct class_stack_node, current_class_stack,
5714 current_class_stack_size);
5717 /* Insert a new entry on the class stack. */
5718 csn = current_class_stack + current_class_depth;
5719 csn->name = current_class_name;
5720 csn->type = current_class_type;
5721 csn->access = current_access_specifier;
5722 csn->names_used = 0;
5724 current_class_depth++;
5726 /* Now set up the new type. */
5727 current_class_name = TYPE_NAME (type);
5728 if (TREE_CODE (current_class_name) == TYPE_DECL)
5729 current_class_name = DECL_NAME (current_class_name);
5730 current_class_type = type;
5732 /* By default, things in classes are private, while things in
5733 structures or unions are public. */
5734 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5735 ? access_private_node
5736 : access_public_node);
5738 if (previous_class_level
5739 && type != previous_class_level->this_entity
5740 && current_class_depth == 1)
5742 /* Forcibly remove any old class remnants. */
5743 invalidate_class_lookup_cache ();
5746 if (!previous_class_level
5747 || type != previous_class_level->this_entity
5748 || current_class_depth > 1)
5751 restore_class_cache ();
5754 /* When we exit a toplevel class scope, we save its binding level so
5755 that we can restore it quickly. Here, we've entered some other
5756 class, so we must invalidate our cache. */
5759 invalidate_class_lookup_cache (void)
5761 previous_class_level = NULL;
5764 /* Get out of the current class scope. If we were in a class scope
5765 previously, that is the one popped to. */
5772 current_class_depth--;
5773 current_class_name = current_class_stack[current_class_depth].name;
5774 current_class_type = current_class_stack[current_class_depth].type;
5775 current_access_specifier = current_class_stack[current_class_depth].access;
5776 if (current_class_stack[current_class_depth].names_used)
5777 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5780 /* Mark the top of the class stack as hidden. */
5783 push_class_stack (void)
5785 if (current_class_depth)
5786 ++current_class_stack[current_class_depth - 1].hidden;
5789 /* Mark the top of the class stack as un-hidden. */
5792 pop_class_stack (void)
5794 if (current_class_depth)
5795 --current_class_stack[current_class_depth - 1].hidden;
5798 /* Returns 1 if the class type currently being defined is either T or
5799 a nested type of T. */
5802 currently_open_class (tree t)
5806 if (!CLASS_TYPE_P (t))
5809 /* We start looking from 1 because entry 0 is from global scope,
5811 for (i = current_class_depth; i > 0; --i)
5814 if (i == current_class_depth)
5815 c = current_class_type;
5818 if (current_class_stack[i].hidden)
5820 c = current_class_stack[i].type;
5824 if (same_type_p (c, t))
5830 /* If either current_class_type or one of its enclosing classes are derived
5831 from T, return the appropriate type. Used to determine how we found
5832 something via unqualified lookup. */
5835 currently_open_derived_class (tree t)
5839 /* The bases of a dependent type are unknown. */
5840 if (dependent_type_p (t))
5843 if (!current_class_type)
5846 if (DERIVED_FROM_P (t, current_class_type))
5847 return current_class_type;
5849 for (i = current_class_depth - 1; i > 0; --i)
5851 if (current_class_stack[i].hidden)
5853 if (DERIVED_FROM_P (t, current_class_stack[i].type))
5854 return current_class_stack[i].type;
5860 /* When entering a class scope, all enclosing class scopes' names with
5861 static meaning (static variables, static functions, types and
5862 enumerators) have to be visible. This recursive function calls
5863 pushclass for all enclosing class contexts until global or a local
5864 scope is reached. TYPE is the enclosed class. */
5867 push_nested_class (tree type)
5869 /* A namespace might be passed in error cases, like A::B:C. */
5870 if (type == NULL_TREE
5871 || !CLASS_TYPE_P (type))
5874 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
5879 /* Undoes a push_nested_class call. */
5882 pop_nested_class (void)
5884 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5887 if (context && CLASS_TYPE_P (context))
5888 pop_nested_class ();
5891 /* Returns the number of extern "LANG" blocks we are nested within. */
5894 current_lang_depth (void)
5896 return VEC_length (tree, current_lang_base);
5899 /* Set global variables CURRENT_LANG_NAME to appropriate value
5900 so that behavior of name-mangling machinery is correct. */
5903 push_lang_context (tree name)
5905 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
5907 if (name == lang_name_cplusplus)
5909 current_lang_name = name;
5911 else if (name == lang_name_java)
5913 current_lang_name = name;
5914 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5915 (See record_builtin_java_type in decl.c.) However, that causes
5916 incorrect debug entries if these types are actually used.
5917 So we re-enable debug output after extern "Java". */
5918 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
5919 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
5920 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
5921 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
5922 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
5923 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
5924 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
5925 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
5927 else if (name == lang_name_c)
5929 current_lang_name = name;
5932 error ("language string %<\"%E\"%> not recognized", name);
5935 /* Get out of the current language scope. */
5938 pop_lang_context (void)
5940 current_lang_name = VEC_pop (tree, current_lang_base);
5943 /* Type instantiation routines. */
5945 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
5946 matches the TARGET_TYPE. If there is no satisfactory match, return
5947 error_mark_node, and issue an error & warning messages under
5948 control of FLAGS. Permit pointers to member function if FLAGS
5949 permits. If TEMPLATE_ONLY, the name of the overloaded function was
5950 a template-id, and EXPLICIT_TARGS are the explicitly provided
5953 If OVERLOAD is for one or more member functions, then ACCESS_PATH
5954 is the base path used to reference those member functions. If
5955 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
5956 resolved to a member function, access checks will be performed and
5957 errors issued if appropriate. */
5960 resolve_address_of_overloaded_function (tree target_type,
5962 tsubst_flags_t flags,
5964 tree explicit_targs,
5967 /* Here's what the standard says:
5971 If the name is a function template, template argument deduction
5972 is done, and if the argument deduction succeeds, the deduced
5973 arguments are used to generate a single template function, which
5974 is added to the set of overloaded functions considered.
5976 Non-member functions and static member functions match targets of
5977 type "pointer-to-function" or "reference-to-function." Nonstatic
5978 member functions match targets of type "pointer-to-member
5979 function;" the function type of the pointer to member is used to
5980 select the member function from the set of overloaded member
5981 functions. If a nonstatic member function is selected, the
5982 reference to the overloaded function name is required to have the
5983 form of a pointer to member as described in 5.3.1.
5985 If more than one function is selected, any template functions in
5986 the set are eliminated if the set also contains a non-template
5987 function, and any given template function is eliminated if the
5988 set contains a second template function that is more specialized
5989 than the first according to the partial ordering rules 14.5.5.2.
5990 After such eliminations, if any, there shall remain exactly one
5991 selected function. */
5994 int is_reference = 0;
5995 /* We store the matches in a TREE_LIST rooted here. The functions
5996 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
5997 interoperability with most_specialized_instantiation. */
5998 tree matches = NULL_TREE;
6001 /* By the time we get here, we should be seeing only real
6002 pointer-to-member types, not the internal POINTER_TYPE to
6003 METHOD_TYPE representation. */
6004 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6005 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6007 gcc_assert (is_overloaded_fn (overload));
6009 /* Check that the TARGET_TYPE is reasonable. */
6010 if (TYPE_PTRFN_P (target_type))
6012 else if (TYPE_PTRMEMFUNC_P (target_type))
6013 /* This is OK, too. */
6015 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6017 /* This is OK, too. This comes from a conversion to reference
6019 target_type = build_reference_type (target_type);
6024 if (flags & tf_error)
6025 error ("cannot resolve overloaded function %qD based on"
6026 " conversion to type %qT",
6027 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6028 return error_mark_node;
6031 /* If we can find a non-template function that matches, we can just
6032 use it. There's no point in generating template instantiations
6033 if we're just going to throw them out anyhow. But, of course, we
6034 can only do this when we don't *need* a template function. */
6039 for (fns = overload; fns; fns = OVL_NEXT (fns))
6041 tree fn = OVL_CURRENT (fns);
6044 if (TREE_CODE (fn) == TEMPLATE_DECL)
6045 /* We're not looking for templates just yet. */
6048 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6050 /* We're looking for a non-static member, and this isn't
6051 one, or vice versa. */
6054 /* Ignore functions which haven't been explicitly
6056 if (DECL_ANTICIPATED (fn))
6059 /* See if there's a match. */
6060 fntype = TREE_TYPE (fn);
6062 fntype = build_ptrmemfunc_type (build_pointer_type (fntype));
6063 else if (!is_reference)
6064 fntype = build_pointer_type (fntype);
6066 if (can_convert_arg (target_type, fntype, fn, LOOKUP_NORMAL))
6067 matches = tree_cons (fn, NULL_TREE, matches);
6071 /* Now, if we've already got a match (or matches), there's no need
6072 to proceed to the template functions. But, if we don't have a
6073 match we need to look at them, too. */
6076 tree target_fn_type;
6077 tree target_arg_types;
6078 tree target_ret_type;
6081 unsigned int nargs, ia;
6086 = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (target_type));
6088 target_fn_type = TREE_TYPE (target_type);
6089 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6090 target_ret_type = TREE_TYPE (target_fn_type);
6092 /* Never do unification on the 'this' parameter. */
6093 if (TREE_CODE (target_fn_type) == METHOD_TYPE)
6094 target_arg_types = TREE_CHAIN (target_arg_types);
6096 nargs = list_length (target_arg_types);
6097 args = XALLOCAVEC (tree, nargs);
6098 for (arg = target_arg_types, ia = 0;
6099 arg != NULL_TREE && arg != void_list_node;
6100 arg = TREE_CHAIN (arg), ++ia)
6101 args[ia] = TREE_VALUE (arg);
6104 for (fns = overload; fns; fns = OVL_NEXT (fns))
6106 tree fn = OVL_CURRENT (fns);
6108 tree instantiation_type;
6111 if (TREE_CODE (fn) != TEMPLATE_DECL)
6112 /* We're only looking for templates. */
6115 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6117 /* We're not looking for a non-static member, and this is
6118 one, or vice versa. */
6121 /* Try to do argument deduction. */
6122 targs = make_tree_vec (DECL_NTPARMS (fn));
6123 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6124 target_ret_type, DEDUCE_EXACT,
6126 /* Argument deduction failed. */
6129 /* Instantiate the template. */
6130 instantiation = instantiate_template (fn, targs, flags);
6131 if (instantiation == error_mark_node)
6132 /* Instantiation failed. */
6135 /* See if there's a match. */
6136 instantiation_type = TREE_TYPE (instantiation);
6138 instantiation_type =
6139 build_ptrmemfunc_type (build_pointer_type (instantiation_type));
6140 else if (!is_reference)
6141 instantiation_type = build_pointer_type (instantiation_type);
6142 if (can_convert_arg (target_type, instantiation_type, instantiation,
6144 matches = tree_cons (instantiation, fn, matches);
6147 /* Now, remove all but the most specialized of the matches. */
6150 tree match = most_specialized_instantiation (matches);
6152 if (match != error_mark_node)
6153 matches = tree_cons (TREE_PURPOSE (match),
6159 /* Now we should have exactly one function in MATCHES. */
6160 if (matches == NULL_TREE)
6162 /* There were *no* matches. */
6163 if (flags & tf_error)
6165 error ("no matches converting function %qD to type %q#T",
6166 DECL_NAME (OVL_CURRENT (overload)),
6169 /* print_candidates expects a chain with the functions in
6170 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6171 so why be clever?). */
6172 for (; overload; overload = OVL_NEXT (overload))
6173 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
6176 print_candidates (matches);
6178 return error_mark_node;
6180 else if (TREE_CHAIN (matches))
6182 /* There were too many matches. First check if they're all
6183 the same function. */
6186 fn = TREE_PURPOSE (matches);
6187 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6188 if (!decls_match (fn, TREE_PURPOSE (matches)))
6193 if (flags & tf_error)
6195 error ("converting overloaded function %qD to type %q#T is ambiguous",
6196 DECL_NAME (OVL_FUNCTION (overload)),
6199 /* Since print_candidates expects the functions in the
6200 TREE_VALUE slot, we flip them here. */
6201 for (match = matches; match; match = TREE_CHAIN (match))
6202 TREE_VALUE (match) = TREE_PURPOSE (match);
6204 print_candidates (matches);
6207 return error_mark_node;
6211 /* Good, exactly one match. Now, convert it to the correct type. */
6212 fn = TREE_PURPOSE (matches);
6214 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6215 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6217 static int explained;
6219 if (!(flags & tf_error))
6220 return error_mark_node;
6222 permerror (input_location, "assuming pointer to member %qD", fn);
6225 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6230 /* If we're doing overload resolution purely for the purpose of
6231 determining conversion sequences, we should not consider the
6232 function used. If this conversion sequence is selected, the
6233 function will be marked as used at this point. */
6234 if (!(flags & tf_conv))
6236 /* Make =delete work with SFINAE. */
6237 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6238 return error_mark_node;
6243 /* We could not check access to member functions when this
6244 expression was originally created since we did not know at that
6245 time to which function the expression referred. */
6246 if (!(flags & tf_no_access_control)
6247 && DECL_FUNCTION_MEMBER_P (fn))
6249 gcc_assert (access_path);
6250 perform_or_defer_access_check (access_path, fn, fn);
6253 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6254 return cp_build_unary_op (ADDR_EXPR, fn, 0, flags);
6257 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6258 will mark the function as addressed, but here we must do it
6260 cxx_mark_addressable (fn);
6266 /* This function will instantiate the type of the expression given in
6267 RHS to match the type of LHSTYPE. If errors exist, then return
6268 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6269 we complain on errors. If we are not complaining, never modify rhs,
6270 as overload resolution wants to try many possible instantiations, in
6271 the hope that at least one will work.
6273 For non-recursive calls, LHSTYPE should be a function, pointer to
6274 function, or a pointer to member function. */
6277 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6279 tsubst_flags_t flags_in = flags;
6280 tree access_path = NULL_TREE;
6282 flags &= ~tf_ptrmem_ok;
6284 if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
6286 if (flags & tf_error)
6287 error ("not enough type information");
6288 return error_mark_node;
6291 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6293 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6295 if (flag_ms_extensions
6296 && TYPE_PTRMEMFUNC_P (lhstype)
6297 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6298 /* Microsoft allows `A::f' to be resolved to a
6299 pointer-to-member. */
6303 if (flags & tf_error)
6304 error ("argument of type %qT does not match %qT",
6305 TREE_TYPE (rhs), lhstype);
6306 return error_mark_node;
6310 if (TREE_CODE (rhs) == BASELINK)
6312 access_path = BASELINK_ACCESS_BINFO (rhs);
6313 rhs = BASELINK_FUNCTIONS (rhs);
6316 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6317 deduce any type information. */
6318 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6320 if (flags & tf_error)
6321 error ("not enough type information");
6322 return error_mark_node;
6325 /* There only a few kinds of expressions that may have a type
6326 dependent on overload resolution. */
6327 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6328 || TREE_CODE (rhs) == COMPONENT_REF
6329 || really_overloaded_fn (rhs)
6330 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
6332 /* This should really only be used when attempting to distinguish
6333 what sort of a pointer to function we have. For now, any
6334 arithmetic operation which is not supported on pointers
6335 is rejected as an error. */
6337 switch (TREE_CODE (rhs))
6341 tree member = TREE_OPERAND (rhs, 1);
6343 member = instantiate_type (lhstype, member, flags);
6344 if (member != error_mark_node
6345 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6346 /* Do not lose object's side effects. */
6347 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6348 TREE_OPERAND (rhs, 0), member);
6353 rhs = TREE_OPERAND (rhs, 1);
6354 if (BASELINK_P (rhs))
6355 return instantiate_type (lhstype, rhs, flags_in);
6357 /* This can happen if we are forming a pointer-to-member for a
6359 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6363 case TEMPLATE_ID_EXPR:
6365 tree fns = TREE_OPERAND (rhs, 0);
6366 tree args = TREE_OPERAND (rhs, 1);
6369 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6370 /*template_only=*/true,
6377 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6378 /*template_only=*/false,
6379 /*explicit_targs=*/NULL_TREE,
6384 if (PTRMEM_OK_P (rhs))
6385 flags |= tf_ptrmem_ok;
6387 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6391 return error_mark_node;
6396 return error_mark_node;
6399 /* Return the name of the virtual function pointer field
6400 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6401 this may have to look back through base types to find the
6402 ultimate field name. (For single inheritance, these could
6403 all be the same name. Who knows for multiple inheritance). */
6406 get_vfield_name (tree type)
6408 tree binfo, base_binfo;
6411 for (binfo = TYPE_BINFO (type);
6412 BINFO_N_BASE_BINFOS (binfo);
6415 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6417 if (BINFO_VIRTUAL_P (base_binfo)
6418 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6422 type = BINFO_TYPE (binfo);
6423 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6424 + TYPE_NAME_LENGTH (type) + 2);
6425 sprintf (buf, VFIELD_NAME_FORMAT,
6426 IDENTIFIER_POINTER (constructor_name (type)));
6427 return get_identifier (buf);
6431 print_class_statistics (void)
6433 #ifdef GATHER_STATISTICS
6434 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6435 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6438 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6439 n_vtables, n_vtable_searches);
6440 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6441 n_vtable_entries, n_vtable_elems);
6446 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6447 according to [class]:
6448 The class-name is also inserted
6449 into the scope of the class itself. For purposes of access checking,
6450 the inserted class name is treated as if it were a public member name. */
6453 build_self_reference (void)
6455 tree name = constructor_name (current_class_type);
6456 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6459 DECL_NONLOCAL (value) = 1;
6460 DECL_CONTEXT (value) = current_class_type;
6461 DECL_ARTIFICIAL (value) = 1;
6462 SET_DECL_SELF_REFERENCE_P (value);
6464 if (processing_template_decl)
6465 value = push_template_decl (value);
6467 saved_cas = current_access_specifier;
6468 current_access_specifier = access_public_node;
6469 finish_member_declaration (value);
6470 current_access_specifier = saved_cas;
6473 /* Returns 1 if TYPE contains only padding bytes. */
6476 is_empty_class (tree type)
6478 if (type == error_mark_node)
6481 if (! CLASS_TYPE_P (type))
6484 /* In G++ 3.2, whether or not a class was empty was determined by
6485 looking at its size. */
6486 if (abi_version_at_least (2))
6487 return CLASSTYPE_EMPTY_P (type);
6489 return integer_zerop (CLASSTYPE_SIZE (type));
6492 /* Returns true if TYPE contains an empty class. */
6495 contains_empty_class_p (tree type)
6497 if (is_empty_class (type))
6499 if (CLASS_TYPE_P (type))
6506 for (binfo = TYPE_BINFO (type), i = 0;
6507 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6508 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6510 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6511 if (TREE_CODE (field) == FIELD_DECL
6512 && !DECL_ARTIFICIAL (field)
6513 && is_empty_class (TREE_TYPE (field)))
6516 else if (TREE_CODE (type) == ARRAY_TYPE)
6517 return contains_empty_class_p (TREE_TYPE (type));
6521 /* Returns true if TYPE contains no actual data, just various
6522 possible combinations of empty classes. */
6525 is_really_empty_class (tree type)
6527 if (is_empty_class (type))
6529 if (CLASS_TYPE_P (type))
6536 for (binfo = TYPE_BINFO (type), i = 0;
6537 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6538 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
6540 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6541 if (TREE_CODE (field) == FIELD_DECL
6542 && !DECL_ARTIFICIAL (field)
6543 && !is_really_empty_class (TREE_TYPE (field)))
6547 else if (TREE_CODE (type) == ARRAY_TYPE)
6548 return is_really_empty_class (TREE_TYPE (type));
6552 /* Note that NAME was looked up while the current class was being
6553 defined and that the result of that lookup was DECL. */
6556 maybe_note_name_used_in_class (tree name, tree decl)
6558 splay_tree names_used;
6560 /* If we're not defining a class, there's nothing to do. */
6561 if (!(innermost_scope_kind() == sk_class
6562 && TYPE_BEING_DEFINED (current_class_type)))
6565 /* If there's already a binding for this NAME, then we don't have
6566 anything to worry about. */
6567 if (lookup_member (current_class_type, name,
6568 /*protect=*/0, /*want_type=*/false))
6571 if (!current_class_stack[current_class_depth - 1].names_used)
6572 current_class_stack[current_class_depth - 1].names_used
6573 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6574 names_used = current_class_stack[current_class_depth - 1].names_used;
6576 splay_tree_insert (names_used,
6577 (splay_tree_key) name,
6578 (splay_tree_value) decl);
6581 /* Note that NAME was declared (as DECL) in the current class. Check
6582 to see that the declaration is valid. */
6585 note_name_declared_in_class (tree name, tree decl)
6587 splay_tree names_used;
6590 /* Look to see if we ever used this name. */
6592 = current_class_stack[current_class_depth - 1].names_used;
6596 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6599 /* [basic.scope.class]
6601 A name N used in a class S shall refer to the same declaration
6602 in its context and when re-evaluated in the completed scope of
6604 permerror (input_location, "declaration of %q#D", decl);
6605 permerror (input_location, "changes meaning of %qD from %q+#D",
6606 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6610 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6611 Secondary vtables are merged with primary vtables; this function
6612 will return the VAR_DECL for the primary vtable. */
6615 get_vtbl_decl_for_binfo (tree binfo)
6619 decl = BINFO_VTABLE (binfo);
6620 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
6622 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6623 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6626 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6631 /* Returns the binfo for the primary base of BINFO. If the resulting
6632 BINFO is a virtual base, and it is inherited elsewhere in the
6633 hierarchy, then the returned binfo might not be the primary base of
6634 BINFO in the complete object. Check BINFO_PRIMARY_P or
6635 BINFO_LOST_PRIMARY_P to be sure. */
6638 get_primary_binfo (tree binfo)
6642 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6646 return copied_binfo (primary_base, binfo);
6649 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6652 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6655 fprintf (stream, "%*s", indent, "");
6659 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6660 INDENT should be zero when called from the top level; it is
6661 incremented recursively. IGO indicates the next expected BINFO in
6662 inheritance graph ordering. */
6665 dump_class_hierarchy_r (FILE *stream,
6675 indented = maybe_indent_hierarchy (stream, indent, 0);
6676 fprintf (stream, "%s (0x%lx) ",
6677 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6678 (unsigned long) binfo);
6681 fprintf (stream, "alternative-path\n");
6684 igo = TREE_CHAIN (binfo);
6686 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6687 tree_low_cst (BINFO_OFFSET (binfo), 0));
6688 if (is_empty_class (BINFO_TYPE (binfo)))
6689 fprintf (stream, " empty");
6690 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6691 fprintf (stream, " nearly-empty");
6692 if (BINFO_VIRTUAL_P (binfo))
6693 fprintf (stream, " virtual");
6694 fprintf (stream, "\n");
6697 if (BINFO_PRIMARY_P (binfo))
6699 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6700 fprintf (stream, " primary-for %s (0x%lx)",
6701 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6702 TFF_PLAIN_IDENTIFIER),
6703 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6705 if (BINFO_LOST_PRIMARY_P (binfo))
6707 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6708 fprintf (stream, " lost-primary");
6711 fprintf (stream, "\n");
6713 if (!(flags & TDF_SLIM))
6717 if (BINFO_SUBVTT_INDEX (binfo))
6719 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6720 fprintf (stream, " subvttidx=%s",
6721 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6722 TFF_PLAIN_IDENTIFIER));
6724 if (BINFO_VPTR_INDEX (binfo))
6726 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6727 fprintf (stream, " vptridx=%s",
6728 expr_as_string (BINFO_VPTR_INDEX (binfo),
6729 TFF_PLAIN_IDENTIFIER));
6731 if (BINFO_VPTR_FIELD (binfo))
6733 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6734 fprintf (stream, " vbaseoffset=%s",
6735 expr_as_string (BINFO_VPTR_FIELD (binfo),
6736 TFF_PLAIN_IDENTIFIER));
6738 if (BINFO_VTABLE (binfo))
6740 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6741 fprintf (stream, " vptr=%s",
6742 expr_as_string (BINFO_VTABLE (binfo),
6743 TFF_PLAIN_IDENTIFIER));
6747 fprintf (stream, "\n");
6750 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6751 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6756 /* Dump the BINFO hierarchy for T. */
6759 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6761 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6762 fprintf (stream, " size=%lu align=%lu\n",
6763 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6764 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6765 fprintf (stream, " base size=%lu base align=%lu\n",
6766 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6768 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6770 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6771 fprintf (stream, "\n");
6774 /* Debug interface to hierarchy dumping. */
6777 debug_class (tree t)
6779 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6783 dump_class_hierarchy (tree t)
6786 FILE *stream = dump_begin (TDI_class, &flags);
6790 dump_class_hierarchy_1 (stream, flags, t);
6791 dump_end (TDI_class, stream);
6796 dump_array (FILE * stream, tree decl)
6799 unsigned HOST_WIDE_INT ix;
6801 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6803 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6805 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6806 fprintf (stream, " %s entries",
6807 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6808 TFF_PLAIN_IDENTIFIER));
6809 fprintf (stream, "\n");
6811 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
6813 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
6814 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
6818 dump_vtable (tree t, tree binfo, tree vtable)
6821 FILE *stream = dump_begin (TDI_class, &flags);
6826 if (!(flags & TDF_SLIM))
6828 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6830 fprintf (stream, "%s for %s",
6831 ctor_vtbl_p ? "Construction vtable" : "Vtable",
6832 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6835 if (!BINFO_VIRTUAL_P (binfo))
6836 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6837 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6839 fprintf (stream, "\n");
6840 dump_array (stream, vtable);
6841 fprintf (stream, "\n");
6844 dump_end (TDI_class, stream);
6848 dump_vtt (tree t, tree vtt)
6851 FILE *stream = dump_begin (TDI_class, &flags);
6856 if (!(flags & TDF_SLIM))
6858 fprintf (stream, "VTT for %s\n",
6859 type_as_string (t, TFF_PLAIN_IDENTIFIER));
6860 dump_array (stream, vtt);
6861 fprintf (stream, "\n");
6864 dump_end (TDI_class, stream);
6867 /* Dump a function or thunk and its thunkees. */
6870 dump_thunk (FILE *stream, int indent, tree thunk)
6872 static const char spaces[] = " ";
6873 tree name = DECL_NAME (thunk);
6876 fprintf (stream, "%.*s%p %s %s", indent, spaces,
6878 !DECL_THUNK_P (thunk) ? "function"
6879 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6880 name ? IDENTIFIER_POINTER (name) : "<unset>");
6881 if (DECL_THUNK_P (thunk))
6883 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6884 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6886 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6887 if (!virtual_adjust)
6889 else if (DECL_THIS_THUNK_P (thunk))
6890 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
6891 tree_low_cst (virtual_adjust, 0));
6893 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6894 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6895 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6896 if (THUNK_ALIAS (thunk))
6897 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6899 fprintf (stream, "\n");
6900 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6901 dump_thunk (stream, indent + 2, thunks);
6904 /* Dump the thunks for FN. */
6907 debug_thunks (tree fn)
6909 dump_thunk (stderr, 0, fn);
6912 /* Virtual function table initialization. */
6914 /* Create all the necessary vtables for T and its base classes. */
6917 finish_vtbls (tree t)
6922 /* We lay out the primary and secondary vtables in one contiguous
6923 vtable. The primary vtable is first, followed by the non-virtual
6924 secondary vtables in inheritance graph order. */
6925 list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6926 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6927 TYPE_BINFO (t), t, list);
6929 /* Then come the virtual bases, also in inheritance graph order. */
6930 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6932 if (!BINFO_VIRTUAL_P (vbase))
6934 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6937 if (BINFO_VTABLE (TYPE_BINFO (t)))
6938 initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
6941 /* Initialize the vtable for BINFO with the INITS. */
6944 initialize_vtable (tree binfo, tree inits)
6948 layout_vtable_decl (binfo, list_length (inits));
6949 decl = get_vtbl_decl_for_binfo (binfo);
6950 initialize_artificial_var (decl, inits);
6951 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
6954 /* Build the VTT (virtual table table) for T.
6955 A class requires a VTT if it has virtual bases.
6958 1 - primary virtual pointer for complete object T
6959 2 - secondary VTTs for each direct non-virtual base of T which requires a
6961 3 - secondary virtual pointers for each direct or indirect base of T which
6962 has virtual bases or is reachable via a virtual path from T.
6963 4 - secondary VTTs for each direct or indirect virtual base of T.
6965 Secondary VTTs look like complete object VTTs without part 4. */
6975 /* Build up the initializers for the VTT. */
6977 index = size_zero_node;
6978 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
6980 /* If we didn't need a VTT, we're done. */
6984 /* Figure out the type of the VTT. */
6985 type = build_index_type (size_int (list_length (inits) - 1));
6986 type = build_cplus_array_type (const_ptr_type_node, type);
6988 /* Now, build the VTT object itself. */
6989 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
6990 initialize_artificial_var (vtt, inits);
6991 /* Add the VTT to the vtables list. */
6992 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
6993 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
6998 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
6999 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7000 and CHAIN the vtable pointer for this binfo after construction is
7001 complete. VALUE can also be another BINFO, in which case we recurse. */
7004 binfo_ctor_vtable (tree binfo)
7010 vt = BINFO_VTABLE (binfo);
7011 if (TREE_CODE (vt) == TREE_LIST)
7012 vt = TREE_VALUE (vt);
7013 if (TREE_CODE (vt) == TREE_BINFO)
7022 /* Data for secondary VTT initialization. */
7023 typedef struct secondary_vptr_vtt_init_data_s
7025 /* Is this the primary VTT? */
7028 /* Current index into the VTT. */
7031 /* TREE_LIST of initializers built up. */
7034 /* The type being constructed by this secondary VTT. */
7035 tree type_being_constructed;
7036 } secondary_vptr_vtt_init_data;
7038 /* Recursively build the VTT-initializer for BINFO (which is in the
7039 hierarchy dominated by T). INITS points to the end of the initializer
7040 list to date. INDEX is the VTT index where the next element will be
7041 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7042 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7043 for virtual bases of T. When it is not so, we build the constructor
7044 vtables for the BINFO-in-T variant. */
7047 build_vtt_inits (tree binfo, tree t, tree *inits, tree *index)
7052 tree secondary_vptrs;
7053 secondary_vptr_vtt_init_data data;
7054 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7056 /* We only need VTTs for subobjects with virtual bases. */
7057 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7060 /* We need to use a construction vtable if this is not the primary
7064 build_ctor_vtbl_group (binfo, t);
7066 /* Record the offset in the VTT where this sub-VTT can be found. */
7067 BINFO_SUBVTT_INDEX (binfo) = *index;
7070 /* Add the address of the primary vtable for the complete object. */
7071 init = binfo_ctor_vtable (binfo);
7072 *inits = build_tree_list (NULL_TREE, init);
7073 inits = &TREE_CHAIN (*inits);
7076 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7077 BINFO_VPTR_INDEX (binfo) = *index;
7079 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7081 /* Recursively add the secondary VTTs for non-virtual bases. */
7082 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7083 if (!BINFO_VIRTUAL_P (b))
7084 inits = build_vtt_inits (b, t, inits, index);
7086 /* Add secondary virtual pointers for all subobjects of BINFO with
7087 either virtual bases or reachable along a virtual path, except
7088 subobjects that are non-virtual primary bases. */
7089 data.top_level_p = top_level_p;
7090 data.index = *index;
7092 data.type_being_constructed = BINFO_TYPE (binfo);
7094 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7096 *index = data.index;
7098 /* The secondary vptrs come back in reverse order. After we reverse
7099 them, and add the INITS, the last init will be the first element
7101 secondary_vptrs = data.inits;
7102 if (secondary_vptrs)
7104 *inits = nreverse (secondary_vptrs);
7105 inits = &TREE_CHAIN (secondary_vptrs);
7106 gcc_assert (*inits == NULL_TREE);
7110 /* Add the secondary VTTs for virtual bases in inheritance graph
7112 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7114 if (!BINFO_VIRTUAL_P (b))
7117 inits = build_vtt_inits (b, t, inits, index);
7120 /* Remove the ctor vtables we created. */
7121 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7126 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7127 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7130 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7132 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7134 /* We don't care about bases that don't have vtables. */
7135 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7136 return dfs_skip_bases;
7138 /* We're only interested in proper subobjects of the type being
7140 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7143 /* We're only interested in bases with virtual bases or reachable
7144 via a virtual path from the type being constructed. */
7145 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7146 || binfo_via_virtual (binfo, data->type_being_constructed)))
7147 return dfs_skip_bases;
7149 /* We're not interested in non-virtual primary bases. */
7150 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7153 /* Record the index where this secondary vptr can be found. */
7154 if (data->top_level_p)
7156 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7157 BINFO_VPTR_INDEX (binfo) = data->index;
7159 if (BINFO_VIRTUAL_P (binfo))
7161 /* It's a primary virtual base, and this is not a
7162 construction vtable. Find the base this is primary of in
7163 the inheritance graph, and use that base's vtable
7165 while (BINFO_PRIMARY_P (binfo))
7166 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7170 /* Add the initializer for the secondary vptr itself. */
7171 data->inits = tree_cons (NULL_TREE, binfo_ctor_vtable (binfo), data->inits);
7173 /* Advance the vtt index. */
7174 data->index = size_binop (PLUS_EXPR, data->index,
7175 TYPE_SIZE_UNIT (ptr_type_node));
7180 /* Called from build_vtt_inits via dfs_walk. After building
7181 constructor vtables and generating the sub-vtt from them, we need
7182 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7183 binfo of the base whose sub vtt was generated. */
7186 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7188 tree vtable = BINFO_VTABLE (binfo);
7190 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7191 /* If this class has no vtable, none of its bases do. */
7192 return dfs_skip_bases;
7195 /* This might be a primary base, so have no vtable in this
7199 /* If we scribbled the construction vtable vptr into BINFO, clear it
7201 if (TREE_CODE (vtable) == TREE_LIST
7202 && (TREE_PURPOSE (vtable) == (tree) data))
7203 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7208 /* Build the construction vtable group for BINFO which is in the
7209 hierarchy dominated by T. */
7212 build_ctor_vtbl_group (tree binfo, tree t)
7221 /* See if we've already created this construction vtable group. */
7222 id = mangle_ctor_vtbl_for_type (t, binfo);
7223 if (IDENTIFIER_GLOBAL_VALUE (id))
7226 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7227 /* Build a version of VTBL (with the wrong type) for use in
7228 constructing the addresses of secondary vtables in the
7229 construction vtable group. */
7230 vtbl = build_vtable (t, id, ptr_type_node);
7231 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7232 list = build_tree_list (vtbl, NULL_TREE);
7233 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7236 /* Add the vtables for each of our virtual bases using the vbase in T
7238 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7240 vbase = TREE_CHAIN (vbase))
7244 if (!BINFO_VIRTUAL_P (vbase))
7246 b = copied_binfo (vbase, binfo);
7248 accumulate_vtbl_inits (b, vbase, binfo, t, list);
7250 inits = TREE_VALUE (list);
7252 /* Figure out the type of the construction vtable. */
7253 type = build_index_type (size_int (list_length (inits) - 1));
7254 type = build_cplus_array_type (vtable_entry_type, type);
7256 TREE_TYPE (vtbl) = type;
7257 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7258 layout_decl (vtbl, 0);
7260 /* Initialize the construction vtable. */
7261 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7262 initialize_artificial_var (vtbl, inits);
7263 dump_vtable (t, binfo, vtbl);
7266 /* Add the vtbl initializers for BINFO (and its bases other than
7267 non-virtual primaries) to the list of INITS. BINFO is in the
7268 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7269 the constructor the vtbl inits should be accumulated for. (If this
7270 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7271 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7272 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7273 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7274 but are not necessarily the same in terms of layout. */
7277 accumulate_vtbl_inits (tree binfo,
7285 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7287 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7289 /* If it doesn't have a vptr, we don't do anything. */
7290 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7293 /* If we're building a construction vtable, we're not interested in
7294 subobjects that don't require construction vtables. */
7296 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7297 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7300 /* Build the initializers for the BINFO-in-T vtable. */
7302 = chainon (TREE_VALUE (inits),
7303 dfs_accumulate_vtbl_inits (binfo, orig_binfo,
7304 rtti_binfo, t, inits));
7306 /* Walk the BINFO and its bases. We walk in preorder so that as we
7307 initialize each vtable we can figure out at what offset the
7308 secondary vtable lies from the primary vtable. We can't use
7309 dfs_walk here because we need to iterate through bases of BINFO
7310 and RTTI_BINFO simultaneously. */
7311 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7313 /* Skip virtual bases. */
7314 if (BINFO_VIRTUAL_P (base_binfo))
7316 accumulate_vtbl_inits (base_binfo,
7317 BINFO_BASE_BINFO (orig_binfo, i),
7323 /* Called from accumulate_vtbl_inits. Returns the initializers for
7324 the BINFO vtable. */
7327 dfs_accumulate_vtbl_inits (tree binfo,
7333 tree inits = NULL_TREE;
7334 tree vtbl = NULL_TREE;
7335 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7338 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7340 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7341 primary virtual base. If it is not the same primary in
7342 the hierarchy of T, we'll need to generate a ctor vtable
7343 for it, to place at its location in T. If it is the same
7344 primary, we still need a VTT entry for the vtable, but it
7345 should point to the ctor vtable for the base it is a
7346 primary for within the sub-hierarchy of RTTI_BINFO.
7348 There are three possible cases:
7350 1) We are in the same place.
7351 2) We are a primary base within a lost primary virtual base of
7353 3) We are primary to something not a base of RTTI_BINFO. */
7356 tree last = NULL_TREE;
7358 /* First, look through the bases we are primary to for RTTI_BINFO
7359 or a virtual base. */
7361 while (BINFO_PRIMARY_P (b))
7363 b = BINFO_INHERITANCE_CHAIN (b);
7365 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7368 /* If we run out of primary links, keep looking down our
7369 inheritance chain; we might be an indirect primary. */
7370 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7371 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7375 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7376 base B and it is a base of RTTI_BINFO, this is case 2. In
7377 either case, we share our vtable with LAST, i.e. the
7378 derived-most base within B of which we are a primary. */
7380 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7381 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7382 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7383 binfo_ctor_vtable after everything's been set up. */
7386 /* Otherwise, this is case 3 and we get our own. */
7388 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7396 /* Compute the initializer for this vtable. */
7397 inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7400 /* Figure out the position to which the VPTR should point. */
7401 vtbl = TREE_PURPOSE (l);
7402 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7403 index = size_binop (PLUS_EXPR,
7404 size_int (non_fn_entries),
7405 size_int (list_length (TREE_VALUE (l))));
7406 index = size_binop (MULT_EXPR,
7407 TYPE_SIZE_UNIT (vtable_entry_type),
7409 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7413 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7414 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7415 straighten this out. */
7416 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7417 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7420 /* For an ordinary vtable, set BINFO_VTABLE. */
7421 BINFO_VTABLE (binfo) = vtbl;
7426 static GTY(()) tree abort_fndecl_addr;
7428 /* Construct the initializer for BINFO's virtual function table. BINFO
7429 is part of the hierarchy dominated by T. If we're building a
7430 construction vtable, the ORIG_BINFO is the binfo we should use to
7431 find the actual function pointers to put in the vtable - but they
7432 can be overridden on the path to most-derived in the graph that
7433 ORIG_BINFO belongs. Otherwise,
7434 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7435 BINFO that should be indicated by the RTTI information in the
7436 vtable; it will be a base class of T, rather than T itself, if we
7437 are building a construction vtable.
7439 The value returned is a TREE_LIST suitable for wrapping in a
7440 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7441 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7442 number of non-function entries in the vtable.
7444 It might seem that this function should never be called with a
7445 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7446 base is always subsumed by a derived class vtable. However, when
7447 we are building construction vtables, we do build vtables for
7448 primary bases; we need these while the primary base is being
7452 build_vtbl_initializer (tree binfo,
7456 int* non_fn_entries_p)
7463 VEC(tree,gc) *vbases;
7465 /* Initialize VID. */
7466 memset (&vid, 0, sizeof (vid));
7469 vid.rtti_binfo = rtti_binfo;
7470 vid.last_init = &vid.inits;
7471 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7472 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7473 vid.generate_vcall_entries = true;
7474 /* The first vbase or vcall offset is at index -3 in the vtable. */
7475 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7477 /* Add entries to the vtable for RTTI. */
7478 build_rtti_vtbl_entries (binfo, &vid);
7480 /* Create an array for keeping track of the functions we've
7481 processed. When we see multiple functions with the same
7482 signature, we share the vcall offsets. */
7483 vid.fns = VEC_alloc (tree, gc, 32);
7484 /* Add the vcall and vbase offset entries. */
7485 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7487 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7488 build_vbase_offset_vtbl_entries. */
7489 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7490 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7491 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7493 /* If the target requires padding between data entries, add that now. */
7494 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7498 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7503 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7504 add = tree_cons (NULL_TREE,
7505 build1 (NOP_EXPR, vtable_entry_type,
7512 if (non_fn_entries_p)
7513 *non_fn_entries_p = list_length (vid.inits);
7515 /* Go through all the ordinary virtual functions, building up
7517 vfun_inits = NULL_TREE;
7518 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7522 tree fn, fn_original;
7523 tree init = NULL_TREE;
7527 if (DECL_THUNK_P (fn))
7529 if (!DECL_NAME (fn))
7531 if (THUNK_ALIAS (fn))
7533 fn = THUNK_ALIAS (fn);
7536 fn_original = THUNK_TARGET (fn);
7539 /* If the only definition of this function signature along our
7540 primary base chain is from a lost primary, this vtable slot will
7541 never be used, so just zero it out. This is important to avoid
7542 requiring extra thunks which cannot be generated with the function.
7544 We first check this in update_vtable_entry_for_fn, so we handle
7545 restored primary bases properly; we also need to do it here so we
7546 zero out unused slots in ctor vtables, rather than filling them
7547 with erroneous values (though harmless, apart from relocation
7549 for (b = binfo; ; b = get_primary_binfo (b))
7551 /* We found a defn before a lost primary; go ahead as normal. */
7552 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7555 /* The nearest definition is from a lost primary; clear the
7557 if (BINFO_LOST_PRIMARY_P (b))
7559 init = size_zero_node;
7566 /* Pull the offset for `this', and the function to call, out of
7568 delta = BV_DELTA (v);
7569 vcall_index = BV_VCALL_INDEX (v);
7571 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7572 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7574 /* You can't call an abstract virtual function; it's abstract.
7575 So, we replace these functions with __pure_virtual. */
7576 if (DECL_PURE_VIRTUAL_P (fn_original))
7579 if (abort_fndecl_addr == NULL)
7580 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7581 init = abort_fndecl_addr;
7585 if (!integer_zerop (delta) || vcall_index)
7587 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7588 if (!DECL_NAME (fn))
7591 /* Take the address of the function, considering it to be of an
7592 appropriate generic type. */
7593 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7597 /* And add it to the chain of initializers. */
7598 if (TARGET_VTABLE_USES_DESCRIPTORS)
7601 if (init == size_zero_node)
7602 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7603 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7605 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7607 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7608 TREE_OPERAND (init, 0),
7609 build_int_cst (NULL_TREE, i));
7610 TREE_CONSTANT (fdesc) = 1;
7612 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7616 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7619 /* The initializers for virtual functions were built up in reverse
7620 order; straighten them out now. */
7621 vfun_inits = nreverse (vfun_inits);
7623 /* The negative offset initializers are also in reverse order. */
7624 vid.inits = nreverse (vid.inits);
7626 /* Chain the two together. */
7627 return chainon (vid.inits, vfun_inits);
7630 /* Adds to vid->inits the initializers for the vbase and vcall
7631 offsets in BINFO, which is in the hierarchy dominated by T. */
7634 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7638 /* If this is a derived class, we must first create entries
7639 corresponding to the primary base class. */
7640 b = get_primary_binfo (binfo);
7642 build_vcall_and_vbase_vtbl_entries (b, vid);
7644 /* Add the vbase entries for this base. */
7645 build_vbase_offset_vtbl_entries (binfo, vid);
7646 /* Add the vcall entries for this base. */
7647 build_vcall_offset_vtbl_entries (binfo, vid);
7650 /* Returns the initializers for the vbase offset entries in the vtable
7651 for BINFO (which is part of the class hierarchy dominated by T), in
7652 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7653 where the next vbase offset will go. */
7656 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7660 tree non_primary_binfo;
7662 /* If there are no virtual baseclasses, then there is nothing to
7664 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7669 /* We might be a primary base class. Go up the inheritance hierarchy
7670 until we find the most derived class of which we are a primary base:
7671 it is the offset of that which we need to use. */
7672 non_primary_binfo = binfo;
7673 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7677 /* If we have reached a virtual base, then it must be a primary
7678 base (possibly multi-level) of vid->binfo, or we wouldn't
7679 have called build_vcall_and_vbase_vtbl_entries for it. But it
7680 might be a lost primary, so just skip down to vid->binfo. */
7681 if (BINFO_VIRTUAL_P (non_primary_binfo))
7683 non_primary_binfo = vid->binfo;
7687 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7688 if (get_primary_binfo (b) != non_primary_binfo)
7690 non_primary_binfo = b;
7693 /* Go through the virtual bases, adding the offsets. */
7694 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7696 vbase = TREE_CHAIN (vbase))
7701 if (!BINFO_VIRTUAL_P (vbase))
7704 /* Find the instance of this virtual base in the complete
7706 b = copied_binfo (vbase, binfo);
7708 /* If we've already got an offset for this virtual base, we
7709 don't need another one. */
7710 if (BINFO_VTABLE_PATH_MARKED (b))
7712 BINFO_VTABLE_PATH_MARKED (b) = 1;
7714 /* Figure out where we can find this vbase offset. */
7715 delta = size_binop (MULT_EXPR,
7718 TYPE_SIZE_UNIT (vtable_entry_type)));
7719 if (vid->primary_vtbl_p)
7720 BINFO_VPTR_FIELD (b) = delta;
7722 if (binfo != TYPE_BINFO (t))
7723 /* The vbase offset had better be the same. */
7724 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7726 /* The next vbase will come at a more negative offset. */
7727 vid->index = size_binop (MINUS_EXPR, vid->index,
7728 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7730 /* The initializer is the delta from BINFO to this virtual base.
7731 The vbase offsets go in reverse inheritance-graph order, and
7732 we are walking in inheritance graph order so these end up in
7734 delta = size_diffop (BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7737 = build_tree_list (NULL_TREE,
7738 fold_build1 (NOP_EXPR,
7741 vid->last_init = &TREE_CHAIN (*vid->last_init);
7745 /* Adds the initializers for the vcall offset entries in the vtable
7746 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7750 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7752 /* We only need these entries if this base is a virtual base. We
7753 compute the indices -- but do not add to the vtable -- when
7754 building the main vtable for a class. */
7755 if (binfo == TYPE_BINFO (vid->derived)
7756 || (BINFO_VIRTUAL_P (binfo)
7757 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7758 correspond to VID->DERIVED), we are building a primary
7759 construction virtual table. Since this is a primary
7760 virtual table, we do not need the vcall offsets for
7762 && binfo != vid->rtti_binfo))
7764 /* We need a vcall offset for each of the virtual functions in this
7765 vtable. For example:
7767 class A { virtual void f (); };
7768 class B1 : virtual public A { virtual void f (); };
7769 class B2 : virtual public A { virtual void f (); };
7770 class C: public B1, public B2 { virtual void f (); };
7772 A C object has a primary base of B1, which has a primary base of A. A
7773 C also has a secondary base of B2, which no longer has a primary base
7774 of A. So the B2-in-C construction vtable needs a secondary vtable for
7775 A, which will adjust the A* to a B2* to call f. We have no way of
7776 knowing what (or even whether) this offset will be when we define B2,
7777 so we store this "vcall offset" in the A sub-vtable and look it up in
7778 a "virtual thunk" for B2::f.
7780 We need entries for all the functions in our primary vtable and
7781 in our non-virtual bases' secondary vtables. */
7783 /* If we are just computing the vcall indices -- but do not need
7784 the actual entries -- not that. */
7785 if (!BINFO_VIRTUAL_P (binfo))
7786 vid->generate_vcall_entries = false;
7787 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7788 add_vcall_offset_vtbl_entries_r (binfo, vid);
7792 /* Build vcall offsets, starting with those for BINFO. */
7795 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7801 /* Don't walk into virtual bases -- except, of course, for the
7802 virtual base for which we are building vcall offsets. Any
7803 primary virtual base will have already had its offsets generated
7804 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7805 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7808 /* If BINFO has a primary base, process it first. */
7809 primary_binfo = get_primary_binfo (binfo);
7811 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7813 /* Add BINFO itself to the list. */
7814 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7816 /* Scan the non-primary bases of BINFO. */
7817 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7818 if (base_binfo != primary_binfo)
7819 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7822 /* Called from build_vcall_offset_vtbl_entries_r. */
7825 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7827 /* Make entries for the rest of the virtuals. */
7828 if (abi_version_at_least (2))
7832 /* The ABI requires that the methods be processed in declaration
7833 order. G++ 3.2 used the order in the vtable. */
7834 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7836 orig_fn = TREE_CHAIN (orig_fn))
7837 if (DECL_VINDEX (orig_fn))
7838 add_vcall_offset (orig_fn, binfo, vid);
7842 tree derived_virtuals;
7845 /* If BINFO is a primary base, the most derived class which has
7846 BINFO as a primary base; otherwise, just BINFO. */
7847 tree non_primary_binfo;
7849 /* We might be a primary base class. Go up the inheritance hierarchy
7850 until we find the most derived class of which we are a primary base:
7851 it is the BINFO_VIRTUALS there that we need to consider. */
7852 non_primary_binfo = binfo;
7853 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7857 /* If we have reached a virtual base, then it must be vid->vbase,
7858 because we ignore other virtual bases in
7859 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7860 base (possibly multi-level) of vid->binfo, or we wouldn't
7861 have called build_vcall_and_vbase_vtbl_entries for it. But it
7862 might be a lost primary, so just skip down to vid->binfo. */
7863 if (BINFO_VIRTUAL_P (non_primary_binfo))
7865 gcc_assert (non_primary_binfo == vid->vbase);
7866 non_primary_binfo = vid->binfo;
7870 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7871 if (get_primary_binfo (b) != non_primary_binfo)
7873 non_primary_binfo = b;
7876 if (vid->ctor_vtbl_p)
7877 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7878 where rtti_binfo is the most derived type. */
7880 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7882 for (base_virtuals = BINFO_VIRTUALS (binfo),
7883 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7884 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7886 base_virtuals = TREE_CHAIN (base_virtuals),
7887 derived_virtuals = TREE_CHAIN (derived_virtuals),
7888 orig_virtuals = TREE_CHAIN (orig_virtuals))
7892 /* Find the declaration that originally caused this function to
7893 be present in BINFO_TYPE (binfo). */
7894 orig_fn = BV_FN (orig_virtuals);
7896 /* When processing BINFO, we only want to generate vcall slots for
7897 function slots introduced in BINFO. So don't try to generate
7898 one if the function isn't even defined in BINFO. */
7899 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7902 add_vcall_offset (orig_fn, binfo, vid);
7907 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7910 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7916 /* If there is already an entry for a function with the same
7917 signature as FN, then we do not need a second vcall offset.
7918 Check the list of functions already present in the derived
7920 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7922 if (same_signature_p (derived_entry, orig_fn)
7923 /* We only use one vcall offset for virtual destructors,
7924 even though there are two virtual table entries. */
7925 || (DECL_DESTRUCTOR_P (derived_entry)
7926 && DECL_DESTRUCTOR_P (orig_fn)))
7930 /* If we are building these vcall offsets as part of building
7931 the vtable for the most derived class, remember the vcall
7933 if (vid->binfo == TYPE_BINFO (vid->derived))
7935 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
7936 CLASSTYPE_VCALL_INDICES (vid->derived),
7938 elt->purpose = orig_fn;
7939 elt->value = vid->index;
7942 /* The next vcall offset will be found at a more negative
7944 vid->index = size_binop (MINUS_EXPR, vid->index,
7945 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7947 /* Keep track of this function. */
7948 VEC_safe_push (tree, gc, vid->fns, orig_fn);
7950 if (vid->generate_vcall_entries)
7955 /* Find the overriding function. */
7956 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
7957 if (fn == error_mark_node)
7958 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
7962 base = TREE_VALUE (fn);
7964 /* The vbase we're working on is a primary base of
7965 vid->binfo. But it might be a lost primary, so its
7966 BINFO_OFFSET might be wrong, so we just use the
7967 BINFO_OFFSET from vid->binfo. */
7968 vcall_offset = size_diffop (BINFO_OFFSET (base),
7969 BINFO_OFFSET (vid->binfo));
7970 vcall_offset = fold_build1 (NOP_EXPR, vtable_entry_type,
7973 /* Add the initializer to the vtable. */
7974 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
7975 vid->last_init = &TREE_CHAIN (*vid->last_init);
7979 /* Return vtbl initializers for the RTTI entries corresponding to the
7980 BINFO's vtable. The RTTI entries should indicate the object given
7981 by VID->rtti_binfo. */
7984 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
7993 basetype = BINFO_TYPE (binfo);
7994 t = BINFO_TYPE (vid->rtti_binfo);
7996 /* To find the complete object, we will first convert to our most
7997 primary base, and then add the offset in the vtbl to that value. */
7999 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8000 && !BINFO_LOST_PRIMARY_P (b))
8004 primary_base = get_primary_binfo (b);
8005 gcc_assert (BINFO_PRIMARY_P (primary_base)
8006 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8009 offset = size_diffop (BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8011 /* The second entry is the address of the typeinfo object. */
8013 decl = build_address (get_tinfo_decl (t));
8015 decl = integer_zero_node;
8017 /* Convert the declaration to a type that can be stored in the
8019 init = build_nop (vfunc_ptr_type_node, decl);
8020 *vid->last_init = build_tree_list (NULL_TREE, init);
8021 vid->last_init = &TREE_CHAIN (*vid->last_init);
8023 /* Add the offset-to-top entry. It comes earlier in the vtable than
8024 the typeinfo entry. Convert the offset to look like a
8025 function pointer, so that we can put it in the vtable. */
8026 init = build_nop (vfunc_ptr_type_node, offset);
8027 *vid->last_init = build_tree_list (NULL_TREE, init);
8028 vid->last_init = &TREE_CHAIN (*vid->last_init);
8031 /* Fold a OBJ_TYPE_REF expression to the address of a function.
8032 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
8035 cp_fold_obj_type_ref (tree ref, tree known_type)
8037 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
8038 HOST_WIDE_INT i = 0;
8039 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
8044 i += (TARGET_VTABLE_USES_DESCRIPTORS
8045 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
8051 #ifdef ENABLE_CHECKING
8052 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
8053 DECL_VINDEX (fndecl)));
8056 cgraph_node (fndecl)->local.vtable_method = true;
8058 return build_address (fndecl);
8061 #include "gt-cp-class.h"