1 /* Build expressions with type checking for C++ compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
4 Hacked by Michael Tiemann (tiemann@cygnus.com)
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to
20 the Free Software Foundation, 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
24 /* This file is part of the C++ front end.
25 It contains routines to build C++ expressions given their operands,
26 including computing the types of the result, C and C++ specific error
27 checks, and some optimization.
29 There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
30 and to process initializations in declarations (since they work
31 like a strange sort of assignment). */
35 #include "coretypes.h"
45 #include "diagnostic.h"
49 static tree convert_for_assignment (tree, tree, const char *, tree, int);
50 static tree cp_pointer_int_sum (enum tree_code, tree, tree);
51 static tree rationalize_conditional_expr (enum tree_code, tree);
52 static int comp_ptr_ttypes_real (tree, tree, int);
53 static int comp_ptr_ttypes_const (tree, tree);
54 static bool comp_except_types (tree, tree, bool);
55 static bool comp_array_types (tree, tree, bool);
56 static tree common_base_type (tree, tree);
57 static tree lookup_anon_field (tree, tree);
58 static tree pointer_diff (tree, tree, tree);
59 static tree get_delta_difference (tree, tree, int);
60 static void casts_away_constness_r (tree *, tree *);
61 static bool casts_away_constness (tree, tree);
62 static void maybe_warn_about_returning_address_of_local (tree);
63 static tree lookup_destructor (tree, tree, tree);
65 /* Return the target type of TYPE, which means return T for:
66 T*, T&, T[], T (...), and otherwise, just T. */
69 target_type (tree type)
71 type = non_reference (type);
72 while (TREE_CODE (type) == POINTER_TYPE
73 || TREE_CODE (type) == ARRAY_TYPE
74 || TREE_CODE (type) == FUNCTION_TYPE
75 || TREE_CODE (type) == METHOD_TYPE
76 || TYPE_PTRMEM_P (type))
77 type = TREE_TYPE (type);
81 /* Do `exp = require_complete_type (exp);' to make sure exp
82 does not have an incomplete type. (That includes void types.)
83 Returns the error_mark_node if the VALUE does not have
84 complete type when this function returns. */
87 require_complete_type (tree value)
91 if (processing_template_decl || value == error_mark_node)
94 if (TREE_CODE (value) == OVERLOAD)
95 type = unknown_type_node;
97 type = TREE_TYPE (value);
99 /* First, detect a valid value with a complete type. */
100 if (COMPLETE_TYPE_P (type))
103 if (complete_type_or_else (type, value))
106 return error_mark_node;
109 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
110 a template instantiation, do the instantiation. Returns TYPE,
111 whether or not it could be completed, unless something goes
112 horribly wrong, in which case the error_mark_node is returned. */
115 complete_type (tree type)
117 if (type == NULL_TREE)
118 /* Rather than crash, we return something sure to cause an error
120 return error_mark_node;
122 if (type == error_mark_node || COMPLETE_TYPE_P (type))
124 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
126 tree t = complete_type (TREE_TYPE (type));
127 if (COMPLETE_TYPE_P (t) && ! processing_template_decl)
129 TYPE_NEEDS_CONSTRUCTING (type)
130 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
131 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
132 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
134 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
135 instantiate_class_template (TYPE_MAIN_VARIANT (type));
140 /* Like complete_type, but issue an error if the TYPE cannot be completed.
141 VALUE is used for informative diagnostics. DIAG_TYPE indicates the type
142 of diagnostic: 0 for an error, 1 for a warning, 2 for a pedwarn.
143 Returns NULL_TREE if the type cannot be made complete. */
146 complete_type_or_diagnostic (tree type, tree value, int diag_type)
148 type = complete_type (type);
149 if (type == error_mark_node)
150 /* We already issued an error. */
152 else if (!COMPLETE_TYPE_P (type))
154 cxx_incomplete_type_diagnostic (value, type, diag_type);
161 /* Return truthvalue of whether type of EXP is instantiated. */
164 type_unknown_p (tree exp)
166 return (TREE_CODE (exp) == OVERLOAD
167 || TREE_CODE (exp) == TREE_LIST
168 || TREE_TYPE (exp) == unknown_type_node);
172 /* Return the common type of two parameter lists.
173 We assume that comptypes has already been done and returned 1;
174 if that isn't so, this may crash.
176 As an optimization, free the space we allocate if the parameter
177 lists are already common. */
180 commonparms (tree p1, tree p2)
182 tree oldargs = p1, newargs, n;
186 len = list_length (p1);
187 newargs = tree_last (p1);
189 if (newargs == void_list_node)
198 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
203 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
205 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
207 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
210 else if (! TREE_PURPOSE (p1))
212 if (TREE_PURPOSE (p2))
214 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
220 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
222 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
224 if (TREE_VALUE (p1) != TREE_VALUE (p2))
227 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
230 TREE_VALUE (n) = TREE_VALUE (p1);
238 /* Given a type, perhaps copied for a typedef,
239 find the "original" version of it. */
241 original_type (tree t)
243 while (TYPE_NAME (t) != NULL_TREE)
245 tree x = TYPE_NAME (t);
246 if (TREE_CODE (x) != TYPE_DECL)
248 x = DECL_ORIGINAL_TYPE (x);
256 /* T1 and T2 are arithmetic or enumeration types. Return the type
257 that will result from the "usual arithmetic conversions" on T1 and
258 T2 as described in [expr]. */
261 type_after_usual_arithmetic_conversions (tree t1, tree t2)
263 enum tree_code code1 = TREE_CODE (t1);
264 enum tree_code code2 = TREE_CODE (t2);
267 /* FIXME: Attributes. */
268 my_friendly_assert (ARITHMETIC_TYPE_P (t1)
269 || TREE_CODE (t1) == COMPLEX_TYPE
270 || TREE_CODE (t1) == ENUMERAL_TYPE,
272 my_friendly_assert (ARITHMETIC_TYPE_P (t2)
273 || TREE_CODE (t2) == COMPLEX_TYPE
274 || TREE_CODE (t2) == ENUMERAL_TYPE,
277 /* In what follows, we slightly generalize the rules given in [expr] so
278 as to deal with `long long' and `complex'. First, merge the
280 attributes = (*targetm.merge_type_attributes) (t1, t2);
282 /* If one type is complex, form the common type of the non-complex
283 components, then make that complex. Use T1 or T2 if it is the
285 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
287 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
288 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
290 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
292 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
293 return build_type_attribute_variant (t1, attributes);
294 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
295 return build_type_attribute_variant (t2, attributes);
297 return build_type_attribute_variant (build_complex_type (subtype),
301 /* If only one is real, use it as the result. */
302 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
303 return build_type_attribute_variant (t1, attributes);
304 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
305 return build_type_attribute_variant (t2, attributes);
307 /* Perform the integral promotions. */
308 if (code1 != REAL_TYPE)
310 t1 = type_promotes_to (t1);
311 t2 = type_promotes_to (t2);
314 /* Both real or both integers; use the one with greater precision. */
315 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
316 return build_type_attribute_variant (t1, attributes);
317 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
318 return build_type_attribute_variant (t2, attributes);
320 /* The types are the same; no need to do anything fancy. */
321 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
322 return build_type_attribute_variant (t1, attributes);
324 if (code1 != REAL_TYPE)
326 /* If one is a sizetype, use it so size_binop doesn't blow up. */
327 if (TYPE_IS_SIZETYPE (t1) > TYPE_IS_SIZETYPE (t2))
328 return build_type_attribute_variant (t1, attributes);
329 if (TYPE_IS_SIZETYPE (t2) > TYPE_IS_SIZETYPE (t1))
330 return build_type_attribute_variant (t2, attributes);
332 /* If one is unsigned long long, then convert the other to unsigned
334 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
335 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
336 return build_type_attribute_variant (long_long_unsigned_type_node,
338 /* If one is a long long, and the other is an unsigned long, and
339 long long can represent all the values of an unsigned long, then
340 convert to a long long. Otherwise, convert to an unsigned long
341 long. Otherwise, if either operand is long long, convert the
344 Since we're here, we know the TYPE_PRECISION is the same;
345 therefore converting to long long cannot represent all the values
346 of an unsigned long, so we choose unsigned long long in that
348 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
349 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
351 tree t = ((TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
352 ? long_long_unsigned_type_node
353 : long_long_integer_type_node);
354 return build_type_attribute_variant (t, attributes);
357 /* Go through the same procedure, but for longs. */
358 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
359 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
360 return build_type_attribute_variant (long_unsigned_type_node,
362 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
363 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
365 tree t = ((TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
366 ? long_unsigned_type_node : long_integer_type_node);
367 return build_type_attribute_variant (t, attributes);
369 /* Otherwise prefer the unsigned one. */
370 if (TREE_UNSIGNED (t1))
371 return build_type_attribute_variant (t1, attributes);
373 return build_type_attribute_variant (t2, attributes);
377 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
378 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
379 return build_type_attribute_variant (long_double_type_node,
381 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
382 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
383 return build_type_attribute_variant (double_type_node,
385 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
386 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
387 return build_type_attribute_variant (float_type_node,
390 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
391 the standard C++ floating-point types. Logic earlier in this
392 function has already eliminated the possibility that
393 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
394 compelling reason to choose one or the other. */
395 return build_type_attribute_variant (t1, attributes);
399 /* Subroutine of composite_pointer_type to implement the recursive
400 case. See that function for documentation fo the parameters. */
403 composite_pointer_type_r (tree t1, tree t2, const char* location)
410 /* Determine the types pointed to by T1 and T2. */
411 if (TREE_CODE (t1) == POINTER_TYPE)
413 pointee1 = TREE_TYPE (t1);
414 pointee2 = TREE_TYPE (t2);
418 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
419 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
424 Otherwise, the composite pointer type is a pointer type
425 similar (_conv.qual_) to the type of one of the operands,
426 with a cv-qualification signature (_conv.qual_) that is the
427 union of the cv-qualification signatures of the operand
429 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
430 result_type = pointee1;
431 else if ((TREE_CODE (pointee1) == POINTER_TYPE
432 && TREE_CODE (pointee2) == POINTER_TYPE)
433 || (TYPE_PTR_TO_MEMBER_P (pointee1)
434 && TYPE_PTR_TO_MEMBER_P (pointee2)))
435 result_type = composite_pointer_type_r (pointee1, pointee2, location);
438 pedwarn ("%s between distinct pointer types `%T' and `%T' "
441 result_type = void_type_node;
443 result_type = cp_build_qualified_type (result_type,
444 (cp_type_quals (pointee1)
445 | cp_type_quals (pointee2)));
446 result_type = build_pointer_type (result_type);
447 /* If the original types were pointers to members, so is the
449 if (TYPE_PTR_TO_MEMBER_P (t1))
451 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
452 TYPE_PTRMEM_CLASS_TYPE (t2)))
453 pedwarn ("%s between distinct pointer types `%T' and `%T' "
456 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
460 /* Merge the attributes. */
461 attributes = (*targetm.merge_type_attributes) (t1, t2);
462 return build_type_attribute_variant (result_type, attributes);
465 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
466 ARG1 and ARG2 are the values with those types. The LOCATION is a
467 string describing the current location, in case an error occurs.
469 This routine also implements the computation of a common type for
470 pointers-to-members as per [expr.eq]. */
473 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
474 const char* location)
481 If one operand is a null pointer constant, the composite pointer
482 type is the type of the other operand. */
483 if (null_ptr_cst_p (arg1))
485 if (null_ptr_cst_p (arg2))
492 If one of the operands has type "pointer to cv1 void*", then
493 the other has type "pointer to cv2T", and the composite pointer
494 type is "pointer to cv12 void", where cv12 is the union of cv1
497 If either type is a pointer to void, make sure it is T1. */
498 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
506 /* Now, if T1 is a pointer to void, merge the qualifiers. */
507 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
512 if (pedantic && TYPE_PTRFN_P (t2))
513 pedwarn ("ISO C++ forbids %s between pointer of type `void *' and pointer-to-function", location);
515 = cp_build_qualified_type (void_type_node,
516 (cp_type_quals (TREE_TYPE (t1))
517 | cp_type_quals (TREE_TYPE (t2))));
518 result_type = build_pointer_type (result_type);
519 /* Merge the attributes. */
520 attributes = (*targetm.merge_type_attributes) (t1, t2);
521 return build_type_attribute_variant (result_type, attributes);
524 /* [expr.eq] permits the application of a pointer conversion to
525 bring the pointers to a common type. */
526 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
527 && CLASS_TYPE_P (TREE_TYPE (t1))
528 && CLASS_TYPE_P (TREE_TYPE (t2))
529 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
532 class1 = TREE_TYPE (t1);
533 class2 = TREE_TYPE (t2);
535 if (DERIVED_FROM_P (class1, class2))
536 t2 = (build_pointer_type
537 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
538 else if (DERIVED_FROM_P (class2, class1))
539 t1 = (build_pointer_type
540 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
543 error ("%s between distinct pointer types `%T' and `%T' "
544 "lacks a cast", location, t1, t2);
545 return error_mark_node;
548 /* [expr.eq] permits the application of a pointer-to-member
549 conversion to change the class type of one of the types. */
550 else if (TYPE_PTR_TO_MEMBER_P (t1)
551 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
552 TYPE_PTRMEM_CLASS_TYPE (t2)))
554 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
555 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
557 if (DERIVED_FROM_P (class1, class2))
558 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
559 else if (DERIVED_FROM_P (class2, class1))
560 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
563 error ("%s between distinct pointer-to-member types `%T' and `%T' "
564 "lacks a cast", location, t1, t2);
565 return error_mark_node;
569 return composite_pointer_type_r (t1, t2, location);
572 /* Return the merged type of two types.
573 We assume that comptypes has already been done and returned 1;
574 if that isn't so, this may crash.
576 This just combines attributes and default arguments; any other
577 differences would cause the two types to compare unalike. */
580 merge_types (tree t1, tree t2)
582 enum tree_code code1;
583 enum tree_code code2;
586 /* Save time if the two types are the same. */
589 if (original_type (t1) == original_type (t2))
592 /* If one type is nonsense, use the other. */
593 if (t1 == error_mark_node)
595 if (t2 == error_mark_node)
598 /* Merge the attributes. */
599 attributes = (*targetm.merge_type_attributes) (t1, t2);
601 if (TYPE_PTRMEMFUNC_P (t1))
602 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
603 if (TYPE_PTRMEMFUNC_P (t2))
604 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
606 code1 = TREE_CODE (t1);
607 code2 = TREE_CODE (t2);
613 /* For two pointers, do this recursively on the target type. */
615 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
616 int quals = cp_type_quals (t1);
618 if (code1 == POINTER_TYPE)
619 t1 = build_pointer_type (target);
621 t1 = build_reference_type (target);
622 t1 = build_type_attribute_variant (t1, attributes);
623 t1 = cp_build_qualified_type (t1, quals);
625 if (TREE_CODE (target) == METHOD_TYPE)
626 t1 = build_ptrmemfunc_type (t1);
635 quals = cp_type_quals (t1);
636 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
637 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
638 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
640 t1 = cp_build_qualified_type (t1, quals);
646 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
647 /* Save space: see if the result is identical to one of the args. */
648 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
649 return build_type_attribute_variant (t1, attributes);
650 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
651 return build_type_attribute_variant (t2, attributes);
652 /* Merge the element types, and have a size if either arg has one. */
653 t1 = build_cplus_array_type
654 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
659 /* Function types: prefer the one that specified arg types.
660 If both do, merge the arg types. Also merge the return types. */
662 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
663 tree p1 = TYPE_ARG_TYPES (t1);
664 tree p2 = TYPE_ARG_TYPES (t2);
667 /* Save space: see if the result is identical to one of the args. */
668 if (valtype == TREE_TYPE (t1) && ! p2)
669 return cp_build_type_attribute_variant (t1, attributes);
670 if (valtype == TREE_TYPE (t2) && ! p1)
671 return cp_build_type_attribute_variant (t2, attributes);
673 /* Simple way if one arg fails to specify argument types. */
674 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
676 rval = build_function_type (valtype, p2);
677 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
678 rval = build_exception_variant (rval, raises);
679 return cp_build_type_attribute_variant (rval, attributes);
681 raises = TYPE_RAISES_EXCEPTIONS (t1);
682 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
684 rval = build_function_type (valtype, p1);
686 rval = build_exception_variant (rval, raises);
687 return cp_build_type_attribute_variant (rval, attributes);
690 rval = build_function_type (valtype, commonparms (p1, p2));
691 t1 = build_exception_variant (rval, raises);
697 /* Get this value the long way, since TYPE_METHOD_BASETYPE
698 is just the main variant of this. */
699 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
700 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
703 /* If this was a member function type, get back to the
704 original type of type member function (i.e., without
705 the class instance variable up front. */
706 t1 = build_function_type (TREE_TYPE (t1),
707 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
708 t2 = build_function_type (TREE_TYPE (t2),
709 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
710 t3 = merge_types (t1, t2);
711 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
712 TYPE_ARG_TYPES (t3));
713 t1 = build_exception_variant (t3, raises);
718 /* There is no need to merge attributes into a TYPENAME_TYPE.
719 When the type is instantiated it will have whatever
720 attributes result from the instantiation. */
725 return cp_build_type_attribute_variant (t1, attributes);
728 /* Return the common type of two types.
729 We assume that comptypes has already been done and returned 1;
730 if that isn't so, this may crash.
732 This is the type for the result of most arithmetic operations
733 if the operands have the given two types. */
736 common_type (tree t1, tree t2)
738 enum tree_code code1;
739 enum tree_code code2;
741 /* If one type is nonsense, bail. */
742 if (t1 == error_mark_node || t2 == error_mark_node)
743 return error_mark_node;
745 code1 = TREE_CODE (t1);
746 code2 = TREE_CODE (t2);
748 if ((ARITHMETIC_TYPE_P (t1) || code1 == ENUMERAL_TYPE
749 || code1 == COMPLEX_TYPE)
750 && (ARITHMETIC_TYPE_P (t2) || code2 == ENUMERAL_TYPE
751 || code2 == COMPLEX_TYPE))
752 return type_after_usual_arithmetic_conversions (t1, t2);
754 else if ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
755 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
756 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)))
757 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
763 /* Compare two exception specifier types for exactness or subsetness, if
764 allowed. Returns false for mismatch, true for match (same, or
767 [except.spec] "If a class X ... objects of class X or any class publicly
768 and unambiguously derived from X. Similarly, if a pointer type Y * ...
769 exceptions of type Y * or that are pointers to any type publicly and
770 unambiguously derived from Y. Otherwise a function only allows exceptions
771 that have the same type ..."
772 This does not mention cv qualifiers and is different to what throw
773 [except.throw] and catch [except.catch] will do. They will ignore the
774 top level cv qualifiers, and allow qualifiers in the pointer to class
777 We implement the letter of the standard. */
780 comp_except_types (tree a, tree b, bool exact)
782 if (same_type_p (a, b))
786 if (cp_type_quals (a) || cp_type_quals (b))
789 if (TREE_CODE (a) == POINTER_TYPE
790 && TREE_CODE (b) == POINTER_TYPE)
794 if (cp_type_quals (a) || cp_type_quals (b))
798 if (TREE_CODE (a) != RECORD_TYPE
799 || TREE_CODE (b) != RECORD_TYPE)
802 if (ACCESSIBLY_UNIQUELY_DERIVED_P (a, b))
808 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
809 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
810 otherwise it must be exact. Exception lists are unordered, but
811 we've already filtered out duplicates. Most lists will be in order,
812 we should try to make use of that. */
815 comp_except_specs (tree t1, tree t2, bool exact)
824 if (t1 == NULL_TREE) /* T1 is ... */
825 return t2 == NULL_TREE || !exact;
826 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
827 return t2 != NULL_TREE && !TREE_VALUE (t2);
828 if (t2 == NULL_TREE) /* T2 is ... */
830 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
833 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
834 Count how many we find, to determine exactness. For exact matching and
835 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
837 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
839 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
841 tree a = TREE_VALUE (probe);
842 tree b = TREE_VALUE (t2);
844 if (comp_except_types (a, b, exact))
846 if (probe == base && exact)
847 base = TREE_CHAIN (probe);
852 if (probe == NULL_TREE)
855 return !exact || base == NULL_TREE || length == list_length (t1);
858 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
859 [] can match [size]. */
862 comp_array_types (tree t1, tree t2, bool allow_redeclaration)
871 /* The type of the array elements must be the same. */
872 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
875 d1 = TYPE_DOMAIN (t1);
876 d2 = TYPE_DOMAIN (t2);
881 /* If one of the arrays is dimensionless, and the other has a
882 dimension, they are of different types. However, it is valid to
890 declarations for an array object can specify
891 array types that differ by the presence or absence of a major
892 array bound (_dcl.array_). */
894 return allow_redeclaration;
896 /* Check that the dimensions are the same. */
898 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
900 max1 = TYPE_MAX_VALUE (d1);
901 max2 = TYPE_MAX_VALUE (d2);
902 if (processing_template_decl && !abi_version_at_least (2)
903 && !value_dependent_expression_p (max1)
904 && !value_dependent_expression_p (max2))
906 /* With abi-1 we do not fold non-dependent array bounds, (and
907 consequently mangle them incorrectly). We must therefore
908 fold them here, to verify the domains have the same
914 if (!cp_tree_equal (max1, max2))
920 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
921 is a bitwise-or of the COMPARE_* flags. */
924 comptypes (tree t1, tree t2, int strict)
929 /* Suppress errors caused by previously reported errors. */
930 if (t1 == error_mark_node || t2 == error_mark_node)
933 my_friendly_assert (TYPE_P (t1) && TYPE_P (t2), 20030623);
935 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
936 current instantiation. */
937 if (TREE_CODE (t1) == TYPENAME_TYPE)
939 tree resolved = resolve_typename_type (t1, /*only_current_p=*/true);
941 if (resolved != error_mark_node)
945 if (TREE_CODE (t2) == TYPENAME_TYPE)
947 tree resolved = resolve_typename_type (t2, /*only_current_p=*/true);
949 if (resolved != error_mark_node)
953 /* If either type is the internal version of sizetype, use the
955 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
957 t1 = TYPE_DOMAIN (t1);
959 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
961 t2 = TYPE_DOMAIN (t2);
963 if (TYPE_PTRMEMFUNC_P (t1))
964 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
965 if (TYPE_PTRMEMFUNC_P (t2))
966 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
968 /* Different classes of types can't be compatible. */
969 if (TREE_CODE (t1) != TREE_CODE (t2))
972 /* Qualifiers must match. For array types, we will check when we
973 recur on the array element types. */
974 if (TREE_CODE (t1) != ARRAY_TYPE
975 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
977 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
980 /* Allow for two different type nodes which have essentially the same
981 definition. Note that we already checked for equality of the type
982 qualifiers (just above). */
984 if (TREE_CODE (t1) != ARRAY_TYPE
985 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
988 if (!(*targetm.comp_type_attributes) (t1, t2))
991 switch (TREE_CODE (t1))
993 case TEMPLATE_TEMPLATE_PARM:
994 case BOUND_TEMPLATE_TEMPLATE_PARM:
995 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
996 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
998 if (!comp_template_parms
999 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1000 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1002 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1004 /* Don't check inheritance. */
1005 strict = COMPARE_STRICT;
1010 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1011 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1012 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1013 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1016 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1018 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1024 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1025 strict & ~COMPARE_REDECLARATION))
1030 case REFERENCE_TYPE:
1031 return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1035 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1037 return compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2));
1040 /* Target types must match incl. qualifiers. */
1041 return comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION));
1043 case TEMPLATE_TYPE_PARM:
1044 return (TEMPLATE_TYPE_IDX (t1) == TEMPLATE_TYPE_IDX (t2)
1045 && TEMPLATE_TYPE_LEVEL (t1) == TEMPLATE_TYPE_LEVEL (t2));
1048 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1049 TYPENAME_TYPE_FULLNAME (t2)))
1051 return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
1053 case UNBOUND_CLASS_TEMPLATE:
1054 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1056 return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
1059 return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1067 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1070 at_least_as_qualified_p (tree type1, tree type2)
1072 int q1 = cp_type_quals (type1);
1073 int q2 = cp_type_quals (type2);
1075 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1076 return (q1 & q2) == q2;
1079 /* Returns 1 if TYPE1 is more qualified than TYPE2. */
1082 more_qualified_p (tree type1, tree type2)
1084 int q1 = cp_type_quals (type1);
1085 int q2 = cp_type_quals (type2);
1087 return q1 != q2 && (q1 & q2) == q2;
1090 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1091 more cv-qualified that TYPE1, and 0 otherwise. */
1094 comp_cv_qualification (tree type1, tree type2)
1096 int q1 = cp_type_quals (type1);
1097 int q2 = cp_type_quals (type2);
1102 if ((q1 & q2) == q2)
1104 else if ((q1 & q2) == q1)
1110 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1111 subset of the cv-qualification signature of TYPE2, and the types
1112 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1115 comp_cv_qual_signature (tree type1, tree type2)
1117 if (comp_ptr_ttypes_real (type2, type1, -1))
1119 else if (comp_ptr_ttypes_real (type1, type2, -1))
1125 /* If two types share a common base type, return that basetype.
1126 If there is not a unique most-derived base type, this function
1127 returns ERROR_MARK_NODE. */
1130 common_base_type (tree tt1, tree tt2)
1132 tree best = NULL_TREE;
1135 /* If one is a baseclass of another, that's good enough. */
1136 if (UNIQUELY_DERIVED_FROM_P (tt1, tt2))
1138 if (UNIQUELY_DERIVED_FROM_P (tt2, tt1))
1141 /* Otherwise, try to find a unique baseclass of TT1
1142 that is shared by TT2, and follow that down. */
1143 for (i = CLASSTYPE_N_BASECLASSES (tt1)-1; i >= 0; i--)
1145 tree basetype = TYPE_BINFO_BASETYPE (tt1, i);
1146 tree trial = common_base_type (basetype, tt2);
1149 if (trial == error_mark_node)
1151 if (best == NULL_TREE)
1153 else if (best != trial)
1154 return error_mark_node;
1159 for (i = CLASSTYPE_N_BASECLASSES (tt2)-1; i >= 0; i--)
1161 tree basetype = TYPE_BINFO_BASETYPE (tt2, i);
1162 tree trial = common_base_type (tt1, basetype);
1165 if (trial == error_mark_node)
1167 if (best == NULL_TREE)
1169 else if (best != trial)
1170 return error_mark_node;
1176 /* Subroutines of `comptypes'. */
1178 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1179 equivalent in the sense that functions with those parameter types
1180 can have equivalent types. The two lists must be equivalent,
1181 element by element. */
1184 compparms (tree parms1, tree parms2)
1188 /* An unspecified parmlist matches any specified parmlist
1189 whose argument types don't need default promotions. */
1191 for (t1 = parms1, t2 = parms2;
1193 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1195 /* If one parmlist is shorter than the other,
1196 they fail to match. */
1199 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1206 /* Process a sizeof or alignof expression where the operand is a
1210 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1212 enum tree_code type_code;
1214 const char *op_name;
1216 my_friendly_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR, 20020720);
1217 if (type == error_mark_node)
1218 return error_mark_node;
1220 if (processing_template_decl)
1222 value = build_min (op, size_type_node, type);
1223 TREE_READONLY (value) = 1;
1227 op_name = operator_name_info[(int) op].name;
1229 type = non_reference (type);
1230 type_code = TREE_CODE (type);
1232 if (type_code == METHOD_TYPE)
1234 if (complain && (pedantic || warn_pointer_arith))
1235 pedwarn ("invalid application of `%s' to a member function", op_name);
1236 value = size_one_node;
1239 value = c_sizeof_or_alignof_type (complete_type (type), op, complain);
1244 /* Process a sizeof or alignof expression where the operand is an
1248 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op)
1250 const char *op_name = operator_name_info[(int) op].name;
1252 if (e == error_mark_node)
1253 return error_mark_node;
1255 if (processing_template_decl)
1257 e = build_min (op, size_type_node, e);
1258 TREE_SIDE_EFFECTS (e) = 0;
1259 TREE_READONLY (e) = 1;
1264 if (TREE_CODE (e) == COMPONENT_REF
1265 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1266 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1268 error ("invalid application of `%s' to a bit-field", op_name);
1271 else if (is_overloaded_fn (e))
1273 pedwarn ("ISO C++ forbids applying `%s' to an expression of function type", op_name);
1276 else if (type_unknown_p (e))
1278 cxx_incomplete_type_error (e, TREE_TYPE (e));
1284 return cxx_sizeof_or_alignof_type (e, op, true);
1288 /* Perform the conversions in [expr] that apply when an lvalue appears
1289 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1290 function-to-pointer conversions.
1292 In addition manifest constants are replaced by their values. */
1295 decay_conversion (tree exp)
1298 enum tree_code code;
1300 type = TREE_TYPE (exp);
1301 code = TREE_CODE (type);
1303 if (code == REFERENCE_TYPE)
1305 exp = convert_from_reference (exp);
1306 type = TREE_TYPE (exp);
1307 code = TREE_CODE (type);
1310 if (type == error_mark_node)
1311 return error_mark_node;
1313 if (type_unknown_p (exp))
1315 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1316 return error_mark_node;
1319 /* Constants can be used directly unless they're not loadable. */
1320 if (TREE_CODE (exp) == CONST_DECL)
1321 exp = DECL_INITIAL (exp);
1322 /* Replace a nonvolatile const static variable with its value. We
1323 don't do this for arrays, though; we want the address of the
1324 first element of the array, not the address of the first element
1325 of its initializing constant. */
1326 else if (code != ARRAY_TYPE)
1328 exp = decl_constant_value (exp);
1329 type = TREE_TYPE (exp);
1332 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1333 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1335 if (code == VOID_TYPE)
1337 error ("void value not ignored as it ought to be");
1338 return error_mark_node;
1340 if (code == METHOD_TYPE)
1342 error ("invalid use of non-static member function");
1343 return error_mark_node;
1345 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1346 return build_unary_op (ADDR_EXPR, exp, 0);
1347 if (code == ARRAY_TYPE)
1352 if (TREE_CODE (exp) == INDIRECT_REF)
1353 return build_nop (build_pointer_type (TREE_TYPE (type)),
1354 TREE_OPERAND (exp, 0));
1356 if (TREE_CODE (exp) == COMPOUND_EXPR)
1358 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1359 return build (COMPOUND_EXPR, TREE_TYPE (op1),
1360 TREE_OPERAND (exp, 0), op1);
1364 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1366 error ("invalid use of non-lvalue array");
1367 return error_mark_node;
1370 ptrtype = build_pointer_type (TREE_TYPE (type));
1372 if (TREE_CODE (exp) == VAR_DECL)
1374 if (!cxx_mark_addressable (exp))
1375 return error_mark_node;
1376 adr = build_nop (ptrtype, build_address (exp));
1377 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1380 /* This way is better for a COMPONENT_REF since it can
1381 simplify the offset for a component. */
1382 adr = build_unary_op (ADDR_EXPR, exp, 1);
1383 return cp_convert (ptrtype, adr);
1386 /* [basic.lval]: Class rvalues can have cv-qualified types; non-class
1387 rvalues always have cv-unqualified types. */
1388 if (! CLASS_TYPE_P (type))
1389 exp = cp_convert (TYPE_MAIN_VARIANT (type), exp);
1395 default_conversion (tree exp)
1397 exp = decay_conversion (exp);
1399 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1400 exp = perform_integral_promotions (exp);
1405 /* EXPR is an expression with an integral or enumeration type.
1406 Perform the integral promotions in [conv.prom], and return the
1410 perform_integral_promotions (tree expr)
1415 type = TREE_TYPE (expr);
1416 my_friendly_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type), 20030703);
1417 promoted_type = type_promotes_to (type);
1418 if (type != promoted_type)
1419 expr = cp_convert (promoted_type, expr);
1423 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1427 inline_conversion (tree exp)
1429 if (TREE_CODE (exp) == FUNCTION_DECL)
1430 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1435 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1436 decay_conversion to one. */
1439 string_conv_p (tree totype, tree exp, int warn)
1443 if (! flag_const_strings || TREE_CODE (totype) != POINTER_TYPE)
1446 t = TREE_TYPE (totype);
1447 if (!same_type_p (t, char_type_node)
1448 && !same_type_p (t, wchar_type_node))
1451 if (TREE_CODE (exp) == STRING_CST)
1453 /* Make sure that we don't try to convert between char and wchar_t. */
1454 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1459 /* Is this a string constant which has decayed to 'const char *'? */
1460 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1461 if (!same_type_p (TREE_TYPE (exp), t))
1464 if (TREE_CODE (exp) != ADDR_EXPR
1465 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1469 /* This warning is not very useful, as it complains about printf. */
1470 if (warn && warn_write_strings)
1471 warning ("deprecated conversion from string constant to `%T'", totype);
1476 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1477 can, for example, use as an lvalue. This code used to be in
1478 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1479 expressions, where we're dealing with aggregates. But now it's again only
1480 called from unary_complex_lvalue. The case (in particular) that led to
1481 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1485 rationalize_conditional_expr (enum tree_code code, tree t)
1487 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1488 the first operand is always the one to be used if both operands
1489 are equal, so we know what conditional expression this used to be. */
1490 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1493 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1494 ? LE_EXPR : GE_EXPR),
1495 TREE_OPERAND (t, 0),
1496 TREE_OPERAND (t, 1),
1497 /*overloaded_p=*/NULL),
1498 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1499 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1503 build_conditional_expr (TREE_OPERAND (t, 0),
1504 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1505 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1508 /* Given the TYPE of an anonymous union field inside T, return the
1509 FIELD_DECL for the field. If not found return NULL_TREE. Because
1510 anonymous unions can nest, we must also search all anonymous unions
1511 that are directly reachable. */
1514 lookup_anon_field (tree t, tree type)
1518 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1520 if (TREE_STATIC (field))
1522 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1525 /* If we find it directly, return the field. */
1526 if (DECL_NAME (field) == NULL_TREE
1527 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1532 /* Otherwise, it could be nested, search harder. */
1533 if (DECL_NAME (field) == NULL_TREE
1534 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1536 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1544 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1545 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1546 non-NULL, it indicates the path to the base used to name MEMBER.
1547 If PRESERVE_REFERENCE is true, the expression returned will have
1548 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1549 returned will have the type referred to by the reference.
1551 This function does not perform access control; that is either done
1552 earlier by the parser when the name of MEMBER is resolved to MEMBER
1553 itself, or later when overload resolution selects one of the
1554 functions indicated by MEMBER. */
1557 build_class_member_access_expr (tree object, tree member,
1558 tree access_path, bool preserve_reference)
1562 tree result = NULL_TREE;
1564 if (object == error_mark_node || member == error_mark_node)
1565 return error_mark_node;
1567 if (TREE_CODE (member) == PSEUDO_DTOR_EXPR)
1570 my_friendly_assert (DECL_P (member) || BASELINK_P (member),
1575 The type of the first expression shall be "class object" (of a
1577 object_type = TREE_TYPE (object);
1578 if (!currently_open_class (object_type)
1579 && !complete_type_or_else (object_type, object))
1580 return error_mark_node;
1581 if (!CLASS_TYPE_P (object_type))
1583 error ("request for member `%D' in `%E', which is of non-class type `%T'",
1584 member, object, object_type);
1585 return error_mark_node;
1588 /* The standard does not seem to actually say that MEMBER must be a
1589 member of OBJECT_TYPE. However, that is clearly what is
1591 if (DECL_P (member))
1593 member_scope = DECL_CLASS_CONTEXT (member);
1595 if (TREE_DEPRECATED (member))
1596 warn_deprecated_use (member);
1599 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1600 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1601 presently be the anonymous union. Go outwards until we find a
1602 type related to OBJECT_TYPE. */
1603 while (ANON_AGGR_TYPE_P (member_scope)
1604 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1606 member_scope = TYPE_CONTEXT (member_scope);
1607 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1609 if (TREE_CODE (member) == FIELD_DECL)
1610 error ("invalid use of nonstatic data member '%E'", member);
1612 error ("`%D' is not a member of `%T'", member, object_type);
1613 return error_mark_node;
1616 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1617 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1618 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1620 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1622 object = build_indirect_ref (temp, NULL);
1625 /* In [expr.ref], there is an explicit list of the valid choices for
1626 MEMBER. We check for each of those cases here. */
1627 if (TREE_CODE (member) == VAR_DECL)
1629 /* A static data member. */
1631 /* If OBJECT has side-effects, they are supposed to occur. */
1632 if (TREE_SIDE_EFFECTS (object))
1633 result = build (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1635 else if (TREE_CODE (member) == FIELD_DECL)
1637 /* A non-static data member. */
1642 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1643 && integer_zerop (TREE_OPERAND (object, 0)));
1645 /* Convert OBJECT to the type of MEMBER. */
1646 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1647 TYPE_MAIN_VARIANT (member_scope)))
1652 binfo = lookup_base (access_path ? access_path : object_type,
1653 member_scope, ba_ignore, &kind);
1654 if (binfo == error_mark_node)
1655 return error_mark_node;
1657 /* It is invalid to try to get to a virtual base of a
1658 NULL object. The most common cause is invalid use of
1660 if (null_object_p && kind == bk_via_virtual)
1662 error ("invalid access to non-static data member `%D' of NULL object",
1664 error ("(perhaps the `offsetof' macro was used incorrectly)");
1665 return error_mark_node;
1668 /* Convert to the base. */
1669 object = build_base_path (PLUS_EXPR, object, binfo,
1671 /* If we found the base successfully then we should be able
1672 to convert to it successfully. */
1673 my_friendly_assert (object != error_mark_node,
1677 /* Complain about other invalid uses of offsetof, even though they will
1678 give the right answer. Note that we complain whether or not they
1679 actually used the offsetof macro, since there's no way to know at this
1680 point. So we just give a warning, instead of a pedwarn. */
1681 if (null_object_p && warn_invalid_offsetof
1682 && CLASSTYPE_NON_POD_P (object_type))
1684 warning ("invalid access to non-static data member `%D' of NULL object",
1686 warning ("(perhaps the `offsetof' macro was used incorrectly)");
1689 /* If MEMBER is from an anonymous aggregate, we have converted
1690 OBJECT so that it refers to the class containing the
1691 anonymous union. Generate a reference to the anonymous union
1692 itself, and recur to find MEMBER. */
1693 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1694 /* When this code is called from build_field_call, the
1695 object already has the type of the anonymous union.
1696 That is because the COMPONENT_REF was already
1697 constructed, and was then disassembled before calling
1698 build_field_call. After the function-call code is
1699 cleaned up, this waste can be eliminated. */
1700 && (!same_type_ignoring_top_level_qualifiers_p
1701 (TREE_TYPE (object), DECL_CONTEXT (member))))
1703 tree anonymous_union;
1705 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1706 DECL_CONTEXT (member));
1707 object = build_class_member_access_expr (object,
1709 /*access_path=*/NULL_TREE,
1710 preserve_reference);
1713 /* Compute the type of the field, as described in [expr.ref]. */
1714 type_quals = TYPE_UNQUALIFIED;
1715 member_type = TREE_TYPE (member);
1716 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1718 type_quals = (cp_type_quals (member_type)
1719 | cp_type_quals (object_type));
1721 /* A field is const (volatile) if the enclosing object, or the
1722 field itself, is const (volatile). But, a mutable field is
1723 not const, even within a const object. */
1724 if (DECL_MUTABLE_P (member))
1725 type_quals &= ~TYPE_QUAL_CONST;
1726 member_type = cp_build_qualified_type (member_type, type_quals);
1729 result = fold (build (COMPONENT_REF, member_type, object, member));
1731 /* Mark the expression const or volatile, as appropriate. Even
1732 though we've dealt with the type above, we still have to mark the
1733 expression itself. */
1734 if (type_quals & TYPE_QUAL_CONST)
1735 TREE_READONLY (result) = 1;
1736 else if (type_quals & TYPE_QUAL_VOLATILE)
1737 TREE_THIS_VOLATILE (result) = 1;
1739 else if (BASELINK_P (member))
1741 /* The member is a (possibly overloaded) member function. */
1745 /* If the MEMBER is exactly one static member function, then we
1746 know the type of the expression. Otherwise, we must wait
1747 until overload resolution has been performed. */
1748 functions = BASELINK_FUNCTIONS (member);
1749 if (TREE_CODE (functions) == FUNCTION_DECL
1750 && DECL_STATIC_FUNCTION_P (functions))
1751 type = TREE_TYPE (functions);
1753 type = unknown_type_node;
1754 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1755 base. That will happen when the function is called. */
1756 result = build (COMPONENT_REF, type, object, member);
1758 else if (TREE_CODE (member) == CONST_DECL)
1760 /* The member is an enumerator. */
1762 /* If OBJECT has side-effects, they are supposed to occur. */
1763 if (TREE_SIDE_EFFECTS (object))
1764 result = build (COMPOUND_EXPR, TREE_TYPE (result),
1769 error ("invalid use of `%D'", member);
1770 return error_mark_node;
1773 if (!preserve_reference)
1776 If E2 is declared to have type "reference to T", then ... the
1777 type of E1.E2 is T. */
1778 result = convert_from_reference (result);
1783 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1784 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1787 lookup_destructor (tree object, tree scope, tree dtor_name)
1789 tree object_type = TREE_TYPE (object);
1790 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1792 if (scope && !check_dtor_name (scope, dtor_name))
1794 error ("qualified type `%T' does not match destructor name `~%T'",
1796 return error_mark_node;
1798 if (!same_type_p (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1800 error ("the type being destroyed is `%T', but the destructor refers to `%T'",
1801 TYPE_MAIN_VARIANT (object_type), dtor_type);
1802 return error_mark_node;
1804 if (!TYPE_HAS_DESTRUCTOR (object_type))
1805 return build (PSEUDO_DTOR_EXPR, void_type_node, object, scope,
1807 return lookup_member (object_type, complete_dtor_identifier,
1808 /*protect=*/1, /*want_type=*/false);
1811 /* This function is called by the parser to process a class member
1812 access expression of the form OBJECT.NAME. NAME is a node used by
1813 the parser to represent a name; it is not yet a DECL. It may,
1814 however, be a BASELINK where the BASELINK_FUNCTIONS is a
1815 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
1816 there is no reason to do the lookup twice, so the parser keeps the
1820 finish_class_member_access_expr (tree object, tree name)
1825 tree access_path = NULL_TREE;
1826 tree orig_object = object;
1827 tree orig_name = name;
1829 if (object == error_mark_node || name == error_mark_node)
1830 return error_mark_node;
1832 object_type = TREE_TYPE (object);
1834 if (processing_template_decl)
1836 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
1837 dependent_type_p (object_type)
1838 /* If NAME is just an IDENTIFIER_NODE, then the expression
1840 || TREE_CODE (object) == IDENTIFIER_NODE
1841 /* If NAME is "f<args>", where either 'f' or 'args' is
1842 dependent, then the expression is dependent. */
1843 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
1844 && dependent_template_id_p (TREE_OPERAND (name, 0),
1845 TREE_OPERAND (name, 1)))
1846 /* If NAME is "T::X" where "T" is dependent, then the
1847 expression is dependent. */
1848 || (TREE_CODE (name) == SCOPE_REF
1849 && TYPE_P (TREE_OPERAND (name, 0))
1850 && dependent_type_p (TREE_OPERAND (name, 0))))
1851 return build_min_nt (COMPONENT_REF, object, name);
1852 object = build_non_dependent_expr (object);
1855 if (TREE_CODE (object_type) == REFERENCE_TYPE)
1857 object = convert_from_reference (object);
1858 object_type = TREE_TYPE (object);
1863 The type of the first expression shall be "class object" (of a
1865 if (!currently_open_class (object_type)
1866 && !complete_type_or_else (object_type, object))
1867 return error_mark_node;
1868 if (!CLASS_TYPE_P (object_type))
1870 error ("request for member `%D' in `%E', which is of non-class type `%T'",
1871 name, object, object_type);
1872 return error_mark_node;
1875 if (BASELINK_P (name))
1877 /* A member function that has already been looked up. */
1878 my_friendly_assert ((TREE_CODE (BASELINK_FUNCTIONS (name))
1879 == TEMPLATE_ID_EXPR),
1885 bool is_template_id = false;
1886 tree template_args = NULL_TREE;
1889 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
1891 is_template_id = true;
1892 template_args = TREE_OPERAND (name, 1);
1893 name = TREE_OPERAND (name, 0);
1895 if (TREE_CODE (name) == OVERLOAD)
1896 name = DECL_NAME (get_first_fn (name));
1897 else if (DECL_P (name))
1898 name = DECL_NAME (name);
1901 if (TREE_CODE (name) == SCOPE_REF)
1903 /* A qualified name. The qualifying class or namespace `S' has
1904 already been looked up; it is either a TYPE or a
1905 NAMESPACE_DECL. The member name is either an IDENTIFIER_NODE
1906 or a BIT_NOT_EXPR. */
1907 scope = TREE_OPERAND (name, 0);
1908 name = TREE_OPERAND (name, 1);
1909 my_friendly_assert ((CLASS_TYPE_P (scope)
1910 || TREE_CODE (scope) == NAMESPACE_DECL),
1912 my_friendly_assert ((TREE_CODE (name) == IDENTIFIER_NODE
1913 || TREE_CODE (name) == BIT_NOT_EXPR),
1916 /* If SCOPE is a namespace, then the qualified name does not
1917 name a member of OBJECT_TYPE. */
1918 if (TREE_CODE (scope) == NAMESPACE_DECL)
1920 error ("`%D::%D' is not a member of `%T'",
1921 scope, name, object_type);
1922 return error_mark_node;
1925 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
1926 access_path = lookup_base (object_type, scope, ba_check, NULL);
1927 if (access_path == error_mark_node)
1928 return error_mark_node;
1931 error ("`%T' is not a base of `%T'", scope, object_type);
1932 return error_mark_node;
1938 access_path = object_type;
1941 if (TREE_CODE (name) == BIT_NOT_EXPR)
1942 member = lookup_destructor (object, scope, name);
1945 /* Look up the member. */
1946 member = lookup_member (access_path, name, /*protect=*/1,
1947 /*want_type=*/false);
1948 if (member == NULL_TREE)
1950 error ("'%D' has no member named '%E'", object_type, name);
1951 return error_mark_node;
1953 if (member == error_mark_node)
1954 return error_mark_node;
1959 tree template = member;
1961 if (BASELINK_P (template))
1962 template = lookup_template_function (template, template_args);
1965 error ("`%D' is not a member template function", name);
1966 return error_mark_node;
1971 if (TREE_DEPRECATED (member))
1972 warn_deprecated_use (member);
1974 expr = build_class_member_access_expr (object, member, access_path,
1975 /*preserve_reference=*/false);
1976 if (processing_template_decl && expr != error_mark_node)
1977 return build_min_non_dep (COMPONENT_REF, expr,
1978 orig_object, orig_name);
1982 /* Return an expression for the MEMBER_NAME field in the internal
1983 representation of PTRMEM, a pointer-to-member function. (Each
1984 pointer-to-member function type gets its own RECORD_TYPE so it is
1985 more convenient to access the fields by name than by FIELD_DECL.)
1986 This routine converts the NAME to a FIELD_DECL and then creates the
1987 node for the complete expression. */
1990 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
1996 /* This code is a stripped down version of
1997 build_class_member_access_expr. It does not work to use that
1998 routine directly because it expects the object to be of class
2000 ptrmem_type = TREE_TYPE (ptrmem);
2001 my_friendly_assert (TYPE_PTRMEMFUNC_P (ptrmem_type), 20020804);
2002 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2003 /*want_type=*/false);
2004 member_type = cp_build_qualified_type (TREE_TYPE (member),
2005 cp_type_quals (ptrmem_type));
2006 return fold (build (COMPONENT_REF, member_type, ptrmem, member));
2009 /* Given an expression PTR for a pointer, return an expression
2010 for the value pointed to.
2011 ERRORSTRING is the name of the operator to appear in error messages.
2013 This function may need to overload OPERATOR_FNNAME.
2014 Must also handle REFERENCE_TYPEs for C++. */
2017 build_x_indirect_ref (tree expr, const char *errorstring)
2019 tree orig_expr = expr;
2022 if (processing_template_decl)
2024 if (type_dependent_expression_p (expr))
2025 return build_min_nt (INDIRECT_REF, expr);
2026 expr = build_non_dependent_expr (expr);
2029 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2030 NULL_TREE, /*overloaded_p=*/NULL);
2032 rval = build_indirect_ref (expr, errorstring);
2034 if (processing_template_decl && rval != error_mark_node)
2035 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2041 build_indirect_ref (tree ptr, const char *errorstring)
2045 if (ptr == error_mark_node)
2046 return error_mark_node;
2048 if (ptr == current_class_ptr)
2049 return current_class_ref;
2051 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2052 ? ptr : decay_conversion (ptr));
2053 type = TREE_TYPE (pointer);
2055 if (TYPE_PTR_P (type) || TREE_CODE (type) == REFERENCE_TYPE)
2059 If the type of the expression is "pointer to T," the type
2060 of the result is "T."
2062 We must use the canonical variant because certain parts of
2063 the back end, like fold, do pointer comparisons between
2065 tree t = canonical_type_variant (TREE_TYPE (type));
2067 if (VOID_TYPE_P (t))
2069 /* A pointer to incomplete type (other than cv void) can be
2070 dereferenced [expr.unary.op]/1 */
2071 error ("`%T' is not a pointer-to-object type", type);
2072 return error_mark_node;
2074 else if (TREE_CODE (pointer) == ADDR_EXPR
2075 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2076 /* The POINTER was something like `&x'. We simplify `*&x' to
2078 return TREE_OPERAND (pointer, 0);
2081 tree ref = build1 (INDIRECT_REF, t, pointer);
2083 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2084 so that we get the proper error message if the result is used
2085 to assign to. Also, &* is supposed to be a no-op. */
2086 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2087 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2088 TREE_SIDE_EFFECTS (ref)
2089 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2093 /* `pointer' won't be an error_mark_node if we were given a
2094 pointer to member, so it's cool to check for this here. */
2095 else if (TYPE_PTR_TO_MEMBER_P (type))
2096 error ("invalid use of `%s' on pointer to member", errorstring);
2097 else if (pointer != error_mark_node)
2100 error ("invalid type argument of `%s'", errorstring);
2102 error ("invalid type argument");
2104 return error_mark_node;
2107 /* This handles expressions of the form "a[i]", which denotes
2110 This is logically equivalent in C to *(a+i), but we may do it differently.
2111 If A is a variable or a member, we generate a primitive ARRAY_REF.
2112 This avoids forcing the array out of registers, and can work on
2113 arrays that are not lvalues (for example, members of structures returned
2116 If INDEX is of some user-defined type, it must be converted to
2117 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2118 will inherit the type of the array, which will be some pointer type. */
2121 build_array_ref (tree array, tree idx)
2125 error ("subscript missing in array reference");
2126 return error_mark_node;
2129 if (TREE_TYPE (array) == error_mark_node
2130 || TREE_TYPE (idx) == error_mark_node)
2131 return error_mark_node;
2133 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2135 switch (TREE_CODE (array))
2139 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2140 return build (COMPOUND_EXPR, TREE_TYPE (value),
2141 TREE_OPERAND (array, 0), value);
2145 return build_conditional_expr
2146 (TREE_OPERAND (array, 0),
2147 build_array_ref (TREE_OPERAND (array, 1), idx),
2148 build_array_ref (TREE_OPERAND (array, 2), idx));
2154 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
2155 && TREE_CODE (array) != INDIRECT_REF)
2159 /* Subscripting with type char is likely to lose
2160 on a machine where chars are signed.
2161 So warn on any machine, but optionally.
2162 Don't warn for unsigned char since that type is safe.
2163 Don't warn for signed char because anyone who uses that
2164 must have done so deliberately. */
2165 if (warn_char_subscripts
2166 && TYPE_MAIN_VARIANT (TREE_TYPE (idx)) == char_type_node)
2167 warning ("array subscript has type `char'");
2169 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2171 error ("array subscript is not an integer");
2172 return error_mark_node;
2175 /* Apply integral promotions *after* noticing character types.
2176 (It is unclear why we do these promotions -- the standard
2177 does not say that we should. In fact, the natual thing would
2178 seem to be to convert IDX to ptrdiff_t; we're performing
2179 pointer arithmetic.) */
2180 idx = perform_integral_promotions (idx);
2182 /* An array that is indexed by a non-constant
2183 cannot be stored in a register; we must be able to do
2184 address arithmetic on its address.
2185 Likewise an array of elements of variable size. */
2186 if (TREE_CODE (idx) != INTEGER_CST
2187 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2188 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2191 if (!cxx_mark_addressable (array))
2192 return error_mark_node;
2195 /* An array that is indexed by a constant value which is not within
2196 the array bounds cannot be stored in a register either; because we
2197 would get a crash in store_bit_field/extract_bit_field when trying
2198 to access a non-existent part of the register. */
2199 if (TREE_CODE (idx) == INTEGER_CST
2200 && TYPE_VALUES (TREE_TYPE (array))
2201 && ! int_fits_type_p (idx, TYPE_VALUES (TREE_TYPE (array))))
2203 if (!cxx_mark_addressable (array))
2204 return error_mark_node;
2207 if (pedantic && !lvalue_p (array))
2208 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2210 /* Note in C++ it is valid to subscript a `register' array, since
2211 it is valid to take the address of something with that
2212 storage specification. */
2216 while (TREE_CODE (foo) == COMPONENT_REF)
2217 foo = TREE_OPERAND (foo, 0);
2218 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2219 warning ("subscripting array declared `register'");
2222 type = TREE_TYPE (TREE_TYPE (array));
2223 rval = build (ARRAY_REF, type, array, idx);
2224 /* Array ref is const/volatile if the array elements are
2225 or if the array is.. */
2226 TREE_READONLY (rval)
2227 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2228 TREE_SIDE_EFFECTS (rval)
2229 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2230 TREE_THIS_VOLATILE (rval)
2231 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2232 return require_complete_type (fold (rval));
2236 tree ar = default_conversion (array);
2237 tree ind = default_conversion (idx);
2239 /* Put the integer in IND to simplify error checking. */
2240 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2247 if (ar == error_mark_node)
2250 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2252 error ("subscripted value is neither array nor pointer");
2253 return error_mark_node;
2255 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2257 error ("array subscript is not an integer");
2258 return error_mark_node;
2261 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2266 /* Resolve a pointer to member function. INSTANCE is the object
2267 instance to use, if the member points to a virtual member.
2269 This used to avoid checking for virtual functions if basetype
2270 has no virtual functions, according to an earlier ANSI draft.
2271 With the final ISO C++ rules, such an optimization is
2272 incorrect: A pointer to a derived member can be static_cast
2273 to pointer-to-base-member, as long as the dynamic object
2274 later has the right member. */
2277 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2279 if (TREE_CODE (function) == OFFSET_REF)
2280 function = TREE_OPERAND (function, 1);
2282 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2284 tree idx, delta, e1, e2, e3, vtbl, basetype;
2285 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2287 tree instance_ptr = *instance_ptrptr;
2288 tree instance_save_expr = 0;
2289 if (instance_ptr == error_mark_node)
2291 if (TREE_CODE (function) == PTRMEM_CST)
2293 /* Extracting the function address from a pmf is only
2294 allowed with -Wno-pmf-conversions. It only works for
2296 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2297 e1 = convert (fntype, e1);
2302 error ("object missing in use of `%E'", function);
2303 return error_mark_node;
2307 if (TREE_SIDE_EFFECTS (instance_ptr))
2308 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2310 if (TREE_SIDE_EFFECTS (function))
2311 function = save_expr (function);
2313 /* Start by extracting all the information from the PMF itself. */
2314 e3 = PFN_FROM_PTRMEMFUNC (function);
2315 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2316 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2317 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2319 case ptrmemfunc_vbit_in_pfn:
2320 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2321 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2324 case ptrmemfunc_vbit_in_delta:
2325 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2326 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2333 /* Convert down to the right base before using the instance. First
2335 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2336 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2337 basetype, ba_check, NULL);
2338 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype, 1);
2339 if (instance_ptr == error_mark_node)
2340 return error_mark_node;
2341 /* ...and then the delta in the PMF. */
2342 instance_ptr = build (PLUS_EXPR, TREE_TYPE (instance_ptr),
2343 instance_ptr, delta);
2345 /* Hand back the adjusted 'this' argument to our caller. */
2346 *instance_ptrptr = instance_ptr;
2348 /* Next extract the vtable pointer from the object. */
2349 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2351 vtbl = build_indirect_ref (vtbl, NULL);
2353 /* Finally, extract the function pointer from the vtable. */
2354 e2 = fold (build (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx));
2355 e2 = build_indirect_ref (e2, NULL);
2356 TREE_CONSTANT (e2) = 1;
2358 /* When using function descriptors, the address of the
2359 vtable entry is treated as a function pointer. */
2360 if (TARGET_VTABLE_USES_DESCRIPTORS)
2361 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2362 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2364 TREE_TYPE (e2) = TREE_TYPE (e3);
2365 e1 = build_conditional_expr (e1, e2, e3);
2367 /* Make sure this doesn't get evaluated first inside one of the
2368 branches of the COND_EXPR. */
2369 if (instance_save_expr)
2370 e1 = build (COMPOUND_EXPR, TREE_TYPE (e1),
2371 instance_save_expr, e1);
2379 build_function_call (tree function, tree params)
2381 tree fntype, fndecl;
2382 tree coerced_params;
2384 tree name = NULL_TREE;
2386 tree original = function;
2388 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2389 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2390 if (TREE_CODE (function) == NOP_EXPR
2391 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2392 function = TREE_OPERAND (function, 0);
2394 if (TREE_CODE (function) == FUNCTION_DECL)
2396 name = DECL_NAME (function);
2398 mark_used (function);
2401 /* Convert anything with function type to a pointer-to-function. */
2402 if (pedantic && DECL_MAIN_P (function))
2403 pedwarn ("ISO C++ forbids calling `::main' from within program");
2405 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2406 (because calling an inline function does not mean the function
2407 needs to be separately compiled). */
2409 if (DECL_INLINE (function))
2410 function = inline_conversion (function);
2412 function = build_addr_func (function);
2418 function = build_addr_func (function);
2421 if (function == error_mark_node)
2422 return error_mark_node;
2424 fntype = TREE_TYPE (function);
2426 if (TYPE_PTRMEMFUNC_P (fntype))
2428 error ("must use .* or ->* to call pointer-to-member function in `%E (...)'",
2430 return error_mark_node;
2433 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2434 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2436 if (!((TREE_CODE (fntype) == POINTER_TYPE
2437 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2439 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2441 error ("`%E' cannot be used as a function", original);
2442 return error_mark_node;
2445 /* fntype now gets the type of function pointed to. */
2446 fntype = TREE_TYPE (fntype);
2448 /* Convert the parameters to the types declared in the
2449 function prototype, or apply default promotions. */
2451 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2452 params, fndecl, LOOKUP_NORMAL);
2453 if (coerced_params == error_mark_node)
2454 return error_mark_node;
2456 /* Check for errors in format strings. */
2459 check_function_format (NULL, TYPE_ATTRIBUTES (fntype), coerced_params);
2461 /* Recognize certain built-in functions so we can make tree-codes
2462 other than CALL_EXPR. We do this when it enables fold-const.c
2463 to do something useful. */
2465 if (TREE_CODE (function) == ADDR_EXPR
2466 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
2467 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
2469 result = expand_tree_builtin (TREE_OPERAND (function, 0),
2470 params, coerced_params);
2475 return build_cxx_call (function, params, coerced_params);
2478 /* Convert the actual parameter expressions in the list VALUES
2479 to the types in the list TYPELIST.
2480 If parmdecls is exhausted, or when an element has NULL as its type,
2481 perform the default conversions.
2483 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2485 This is also where warnings about wrong number of args are generated.
2487 Return a list of expressions for the parameters as converted.
2489 Both VALUES and the returned value are chains of TREE_LIST nodes
2490 with the elements of the list in the TREE_VALUE slots of those nodes.
2492 In C++, unspecified trailing parameters can be filled in with their
2493 default arguments, if such were specified. Do so here. */
2496 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2498 tree typetail, valtail;
2499 tree result = NULL_TREE;
2500 const char *called_thing = 0;
2503 /* Argument passing is always copy-initialization. */
2504 flags |= LOOKUP_ONLYCONVERTING;
2508 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2510 if (DECL_NAME (fndecl) == NULL_TREE
2511 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2512 called_thing = "constructor";
2514 called_thing = "member function";
2517 called_thing = "function";
2520 for (valtail = values, typetail = typelist;
2522 valtail = TREE_CHAIN (valtail), i++)
2524 tree type = typetail ? TREE_VALUE (typetail) : 0;
2525 tree val = TREE_VALUE (valtail);
2527 if (val == error_mark_node)
2528 return error_mark_node;
2530 if (type == void_type_node)
2534 cp_error_at ("too many arguments to %s `%+#D'", called_thing,
2536 error ("at this point in file");
2539 error ("too many arguments to function");
2540 /* In case anybody wants to know if this argument
2543 TREE_TYPE (tree_last (result)) = error_mark_node;
2547 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2548 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2549 if (TREE_CODE (val) == NOP_EXPR
2550 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2551 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2552 val = TREE_OPERAND (val, 0);
2554 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2556 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2557 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2558 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2559 val = decay_conversion (val);
2562 if (val == error_mark_node)
2563 return error_mark_node;
2567 /* Formal parm type is specified by a function prototype. */
2570 if (!COMPLETE_TYPE_P (complete_type (type)))
2573 error ("parameter %P of `%D' has incomplete type `%T'",
2576 error ("parameter %P has incomplete type `%T'", i, type);
2577 parmval = error_mark_node;
2581 parmval = convert_for_initialization
2582 (NULL_TREE, type, val, flags,
2583 "argument passing", fndecl, i);
2584 parmval = convert_for_arg_passing (type, parmval);
2587 if (parmval == error_mark_node)
2588 return error_mark_node;
2590 result = tree_cons (NULL_TREE, parmval, result);
2594 if (TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE)
2595 val = convert_from_reference (val);
2597 if (fndecl && DECL_BUILT_IN (fndecl)
2598 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2599 /* Don't do ellipsis conversion for __built_in_constant_p
2600 as this will result in spurious warnings for non-POD
2602 val = require_complete_type (val);
2604 val = convert_arg_to_ellipsis (val);
2606 result = tree_cons (NULL_TREE, val, result);
2610 typetail = TREE_CHAIN (typetail);
2613 if (typetail != 0 && typetail != void_list_node)
2615 /* See if there are default arguments that can be used. */
2616 if (TREE_PURPOSE (typetail)
2617 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2619 for (; typetail != void_list_node; ++i)
2622 = convert_default_arg (TREE_VALUE (typetail),
2623 TREE_PURPOSE (typetail),
2626 if (parmval == error_mark_node)
2627 return error_mark_node;
2629 result = tree_cons (0, parmval, result);
2630 typetail = TREE_CHAIN (typetail);
2631 /* ends with `...'. */
2632 if (typetail == NULL_TREE)
2640 cp_error_at ("too few arguments to %s `%+#D'",
2641 called_thing, fndecl);
2642 error ("at this point in file");
2645 error ("too few arguments to function");
2646 return error_mark_list;
2650 return nreverse (result);
2653 /* Build a binary-operation expression, after performing default
2654 conversions on the operands. CODE is the kind of expression to build. */
2657 build_x_binary_op (enum tree_code code, tree arg1, tree arg2,
2667 if (processing_template_decl)
2669 if (type_dependent_expression_p (arg1)
2670 || type_dependent_expression_p (arg2))
2671 return build_min_nt (code, arg1, arg2);
2672 arg1 = build_non_dependent_expr (arg1);
2673 arg2 = build_non_dependent_expr (arg2);
2676 if (code == DOTSTAR_EXPR)
2677 expr = build_m_component_ref (arg1, arg2);
2679 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
2682 if (processing_template_decl && expr != error_mark_node)
2683 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2688 /* Build a binary-operation expression without default conversions.
2689 CODE is the kind of expression to build.
2690 This function differs from `build' in several ways:
2691 the data type of the result is computed and recorded in it,
2692 warnings are generated if arg data types are invalid,
2693 special handling for addition and subtraction of pointers is known,
2694 and some optimization is done (operations on narrow ints
2695 are done in the narrower type when that gives the same result).
2696 Constant folding is also done before the result is returned.
2698 Note that the operands will never have enumeral types
2699 because either they have just had the default conversions performed
2700 or they have both just been converted to some other type in which
2701 the arithmetic is to be done.
2703 C++: must do special pointer arithmetic when implementing
2704 multiple inheritance, and deal with pointer to member functions. */
2707 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2708 int convert_p ATTRIBUTE_UNUSED)
2711 enum tree_code code0, code1;
2714 /* Expression code to give to the expression when it is built.
2715 Normally this is CODE, which is what the caller asked for,
2716 but in some special cases we change it. */
2717 enum tree_code resultcode = code;
2719 /* Data type in which the computation is to be performed.
2720 In the simplest cases this is the common type of the arguments. */
2721 tree result_type = NULL;
2723 /* Nonzero means operands have already been type-converted
2724 in whatever way is necessary.
2725 Zero means they need to be converted to RESULT_TYPE. */
2728 /* Nonzero means create the expression with this type, rather than
2730 tree build_type = 0;
2732 /* Nonzero means after finally constructing the expression
2733 convert it to this type. */
2734 tree final_type = 0;
2736 /* Nonzero if this is an operation like MIN or MAX which can
2737 safely be computed in short if both args are promoted shorts.
2738 Also implies COMMON.
2739 -1 indicates a bitwise operation; this makes a difference
2740 in the exact conditions for when it is safe to do the operation
2741 in a narrower mode. */
2744 /* Nonzero if this is a comparison operation;
2745 if both args are promoted shorts, compare the original shorts.
2746 Also implies COMMON. */
2747 int short_compare = 0;
2749 /* Nonzero if this is a right-shift operation, which can be computed on the
2750 original short and then promoted if the operand is a promoted short. */
2751 int short_shift = 0;
2753 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2756 /* Apply default conversions. */
2760 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2761 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2762 || code == TRUTH_XOR_EXPR)
2764 if (!really_overloaded_fn (op0))
2765 op0 = decay_conversion (op0);
2766 if (!really_overloaded_fn (op1))
2767 op1 = decay_conversion (op1);
2771 if (!really_overloaded_fn (op0))
2772 op0 = default_conversion (op0);
2773 if (!really_overloaded_fn (op1))
2774 op1 = default_conversion (op1);
2777 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2778 STRIP_TYPE_NOPS (op0);
2779 STRIP_TYPE_NOPS (op1);
2781 /* DTRT if one side is an overloaded function, but complain about it. */
2782 if (type_unknown_p (op0))
2784 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
2785 if (t != error_mark_node)
2787 pedwarn ("assuming cast to type `%T' from overloaded function",
2792 if (type_unknown_p (op1))
2794 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
2795 if (t != error_mark_node)
2797 pedwarn ("assuming cast to type `%T' from overloaded function",
2803 type0 = TREE_TYPE (op0);
2804 type1 = TREE_TYPE (op1);
2806 /* The expression codes of the data types of the arguments tell us
2807 whether the arguments are integers, floating, pointers, etc. */
2808 code0 = TREE_CODE (type0);
2809 code1 = TREE_CODE (type1);
2811 /* If an error was already reported for one of the arguments,
2812 avoid reporting another error. */
2814 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
2815 return error_mark_node;
2820 /* Handle the pointer + int case. */
2821 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2822 return cp_pointer_int_sum (PLUS_EXPR, op0, op1);
2823 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
2824 return cp_pointer_int_sum (PLUS_EXPR, op1, op0);
2830 /* Subtraction of two similar pointers.
2831 We must subtract them as integers, then divide by object size. */
2832 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
2833 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
2835 return pointer_diff (op0, op1, common_type (type0, type1));
2836 /* Handle pointer minus int. Just like pointer plus int. */
2837 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2838 return cp_pointer_int_sum (MINUS_EXPR, op0, op1);
2847 case TRUNC_DIV_EXPR:
2849 case FLOOR_DIV_EXPR:
2850 case ROUND_DIV_EXPR:
2851 case EXACT_DIV_EXPR:
2852 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2853 || code0 == COMPLEX_TYPE)
2854 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2855 || code1 == COMPLEX_TYPE))
2857 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
2858 warning ("division by zero in `%E / 0'", op0);
2859 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
2860 warning ("division by zero in `%E / 0.'", op0);
2862 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
2863 resultcode = RDIV_EXPR;
2865 /* When dividing two signed integers, we have to promote to int.
2866 unless we divide by a constant != -1. Note that default
2867 conversion will have been performed on the operands at this
2868 point, so we have to dig out the original type to find out if
2870 shorten = ((TREE_CODE (op0) == NOP_EXPR
2871 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2872 || (TREE_CODE (op1) == INTEGER_CST
2873 && ! integer_all_onesp (op1)));
2882 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2886 case TRUNC_MOD_EXPR:
2887 case FLOOR_MOD_EXPR:
2888 if (code1 == INTEGER_TYPE && integer_zerop (op1))
2889 warning ("division by zero in `%E %% 0'", op0);
2890 else if (code1 == REAL_TYPE && real_zerop (op1))
2891 warning ("division by zero in `%E %% 0.'", op0);
2893 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2895 /* Although it would be tempting to shorten always here, that loses
2896 on some targets, since the modulo instruction is undefined if the
2897 quotient can't be represented in the computation mode. We shorten
2898 only if unsigned or if dividing by something we know != -1. */
2899 shorten = ((TREE_CODE (op0) == NOP_EXPR
2900 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2901 || (TREE_CODE (op1) == INTEGER_CST
2902 && ! integer_all_onesp (op1)));
2907 case TRUTH_ANDIF_EXPR:
2908 case TRUTH_ORIF_EXPR:
2909 case TRUTH_AND_EXPR:
2911 result_type = boolean_type_node;
2914 /* Shift operations: result has same type as first operand;
2915 always convert second operand to int.
2916 Also set SHORT_SHIFT if shifting rightward. */
2919 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2921 result_type = type0;
2922 if (TREE_CODE (op1) == INTEGER_CST)
2924 if (tree_int_cst_lt (op1, integer_zero_node))
2925 warning ("right shift count is negative");
2928 if (! integer_zerop (op1))
2930 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2931 warning ("right shift count >= width of type");
2934 /* Convert the shift-count to an integer, regardless of
2935 size of value being shifted. */
2936 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2937 op1 = cp_convert (integer_type_node, op1);
2938 /* Avoid converting op1 to result_type later. */
2944 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2946 result_type = type0;
2947 if (TREE_CODE (op1) == INTEGER_CST)
2949 if (tree_int_cst_lt (op1, integer_zero_node))
2950 warning ("left shift count is negative");
2951 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2952 warning ("left shift count >= width of type");
2954 /* Convert the shift-count to an integer, regardless of
2955 size of value being shifted. */
2956 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2957 op1 = cp_convert (integer_type_node, op1);
2958 /* Avoid converting op1 to result_type later. */
2965 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2967 result_type = type0;
2968 if (TREE_CODE (op1) == INTEGER_CST)
2970 if (tree_int_cst_lt (op1, integer_zero_node))
2971 warning ("%s rotate count is negative",
2972 (code == LROTATE_EXPR) ? "left" : "right");
2973 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2974 warning ("%s rotate count >= width of type",
2975 (code == LROTATE_EXPR) ? "left" : "right");
2977 /* Convert the shift-count to an integer, regardless of
2978 size of value being shifted. */
2979 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2980 op1 = cp_convert (integer_type_node, op1);
2986 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
2987 warning ("comparing floating point with == or != is unsafe");
2989 build_type = boolean_type_node;
2990 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2991 || code0 == COMPLEX_TYPE)
2992 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2993 || code1 == COMPLEX_TYPE))
2995 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2996 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
2997 result_type = composite_pointer_type (type0, type1, op0, op1,
2999 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3000 && null_ptr_cst_p (op1))
3001 result_type = type0;
3002 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3003 && null_ptr_cst_p (op0))
3004 result_type = type1;
3005 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3007 result_type = type0;
3008 error ("ISO C++ forbids comparison between pointer and integer");
3010 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3012 result_type = type1;
3013 error ("ISO C++ forbids comparison between pointer and integer");
3015 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3017 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3018 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3019 result_type = TREE_TYPE (op0);
3021 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3022 return cp_build_binary_op (code, op1, op0);
3023 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
3024 && same_type_p (type0, type1))
3026 /* E will be the final comparison. */
3028 /* E1 and E2 are for scratch. */
3036 if (TREE_SIDE_EFFECTS (op0))
3037 op0 = save_expr (op0);
3038 if (TREE_SIDE_EFFECTS (op1))
3039 op1 = save_expr (op1);
3044 && (!op0.pfn || op0.delta == op1.delta))
3046 The reason for the `!op0.pfn' bit is that a NULL
3047 pointer-to-member is any member with a zero PFN; the
3048 DELTA field is unspecified. */
3049 pfn0 = pfn_from_ptrmemfunc (op0);
3050 pfn1 = pfn_from_ptrmemfunc (op1);
3051 delta0 = build_ptrmemfunc_access_expr (op0,
3053 delta1 = build_ptrmemfunc_access_expr (op1,
3055 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3056 e2 = cp_build_binary_op (EQ_EXPR,
3058 cp_convert (TREE_TYPE (pfn0),
3059 integer_zero_node));
3060 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3061 e2 = build (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3062 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3063 if (code == EQ_EXPR)
3065 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3067 else if ((TYPE_PTRMEMFUNC_P (type0)
3068 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0), type1))
3069 || (TYPE_PTRMEMFUNC_P (type1)
3070 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1), type0)))
3076 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3077 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3079 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3080 result_type = composite_pointer_type (type0, type1, op0, op1,
3088 build_type = boolean_type_node;
3089 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3090 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3092 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3093 result_type = composite_pointer_type (type0, type1, op0, op1,
3095 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3096 && integer_zerop (op1))
3097 result_type = type0;
3098 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3099 && integer_zerop (op0))
3100 result_type = type1;
3101 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3103 result_type = type0;
3104 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3106 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3108 result_type = type1;
3109 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3113 case UNORDERED_EXPR:
3120 build_type = integer_type_node;
3121 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3123 error ("unordered comparison on non-floating point argument");
3124 return error_mark_node;
3133 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3135 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
3137 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3139 if (shorten || common || short_compare)
3140 result_type = common_type (type0, type1);
3142 /* For certain operations (which identify themselves by shorten != 0)
3143 if both args were extended from the same smaller type,
3144 do the arithmetic in that type and then extend.
3146 shorten !=0 and !=1 indicates a bitwise operation.
3147 For them, this optimization is safe only if
3148 both args are zero-extended or both are sign-extended.
3149 Otherwise, we might change the result.
3150 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3151 but calculated in (unsigned short) it would be (unsigned short)-1. */
3153 if (shorten && none_complex)
3155 int unsigned0, unsigned1;
3156 tree arg0 = get_narrower (op0, &unsigned0);
3157 tree arg1 = get_narrower (op1, &unsigned1);
3158 /* UNS is 1 if the operation to be done is an unsigned one. */
3159 int uns = TREE_UNSIGNED (result_type);
3162 final_type = result_type;
3164 /* Handle the case that OP0 does not *contain* a conversion
3165 but it *requires* conversion to FINAL_TYPE. */
3167 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3168 unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
3169 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3170 unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
3172 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3174 /* For bitwise operations, signedness of nominal type
3175 does not matter. Consider only how operands were extended. */
3179 /* Note that in all three cases below we refrain from optimizing
3180 an unsigned operation on sign-extended args.
3181 That would not be valid. */
3183 /* Both args variable: if both extended in same way
3184 from same width, do it in that width.
3185 Do it unsigned if args were zero-extended. */
3186 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3187 < TYPE_PRECISION (result_type))
3188 && (TYPE_PRECISION (TREE_TYPE (arg1))
3189 == TYPE_PRECISION (TREE_TYPE (arg0)))
3190 && unsigned0 == unsigned1
3191 && (unsigned0 || !uns))
3192 result_type = c_common_signed_or_unsigned_type
3193 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3194 else if (TREE_CODE (arg0) == INTEGER_CST
3195 && (unsigned1 || !uns)
3196 && (TYPE_PRECISION (TREE_TYPE (arg1))
3197 < TYPE_PRECISION (result_type))
3198 && (type = c_common_signed_or_unsigned_type
3199 (unsigned1, TREE_TYPE (arg1)),
3200 int_fits_type_p (arg0, type)))
3202 else if (TREE_CODE (arg1) == INTEGER_CST
3203 && (unsigned0 || !uns)
3204 && (TYPE_PRECISION (TREE_TYPE (arg0))
3205 < TYPE_PRECISION (result_type))
3206 && (type = c_common_signed_or_unsigned_type
3207 (unsigned0, TREE_TYPE (arg0)),
3208 int_fits_type_p (arg1, type)))
3212 /* Shifts can be shortened if shifting right. */
3217 tree arg0 = get_narrower (op0, &unsigned_arg);
3219 final_type = result_type;
3221 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3222 unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
3224 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3225 /* We can shorten only if the shift count is less than the
3226 number of bits in the smaller type size. */
3227 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3228 /* If arg is sign-extended and then unsigned-shifted,
3229 we can simulate this with a signed shift in arg's type
3230 only if the extended result is at least twice as wide
3231 as the arg. Otherwise, the shift could use up all the
3232 ones made by sign-extension and bring in zeros.
3233 We can't optimize that case at all, but in most machines
3234 it never happens because available widths are 2**N. */
3235 && (!TREE_UNSIGNED (final_type)
3237 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3238 <= TYPE_PRECISION (result_type))))
3240 /* Do an unsigned shift if the operand was zero-extended. */
3242 = c_common_signed_or_unsigned_type (unsigned_arg,
3244 /* Convert value-to-be-shifted to that type. */
3245 if (TREE_TYPE (op0) != result_type)
3246 op0 = cp_convert (result_type, op0);
3251 /* Comparison operations are shortened too but differently.
3252 They identify themselves by setting short_compare = 1. */
3256 /* Don't write &op0, etc., because that would prevent op0
3257 from being kept in a register.
3258 Instead, make copies of the our local variables and
3259 pass the copies by reference, then copy them back afterward. */
3260 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3261 enum tree_code xresultcode = resultcode;
3263 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3265 return cp_convert (boolean_type_node, val);
3266 op0 = xop0, op1 = xop1;
3268 resultcode = xresultcode;
3271 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3272 && warn_sign_compare
3273 /* Do not warn until the template is instantiated; we cannot
3274 bound the ranges of the arguments until that point. */
3275 && !processing_template_decl)
3277 int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0));
3278 int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1));
3280 int unsignedp0, unsignedp1;
3281 tree primop0 = get_narrower (op0, &unsignedp0);
3282 tree primop1 = get_narrower (op1, &unsignedp1);
3284 /* Check for comparison of different enum types. */
3285 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3286 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3287 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3288 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3290 warning ("comparison between types `%#T' and `%#T'",
3291 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3294 /* Give warnings for comparisons between signed and unsigned
3295 quantities that may fail. */
3296 /* Do the checking based on the original operand trees, so that
3297 casts will be considered, but default promotions won't be. */
3299 /* Do not warn if the comparison is being done in a signed type,
3300 since the signed type will only be chosen if it can represent
3301 all the values of the unsigned type. */
3302 if (! TREE_UNSIGNED (result_type))
3304 /* Do not warn if both operands are unsigned. */
3305 else if (op0_signed == op1_signed)
3307 /* Do not warn if the signed quantity is an unsuffixed
3308 integer literal (or some static constant expression
3309 involving such literals or a conditional expression
3310 involving such literals) and it is non-negative. */
3311 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3312 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3314 /* Do not warn if the comparison is an equality operation,
3315 the unsigned quantity is an integral constant and it does
3316 not use the most significant bit of result_type. */
3317 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3318 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3319 && int_fits_type_p (orig_op1, c_common_signed_type
3321 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3322 && int_fits_type_p (orig_op0, c_common_signed_type
3326 warning ("comparison between signed and unsigned integer expressions");
3328 /* Warn if two unsigned values are being compared in a size
3329 larger than their original size, and one (and only one) is the
3330 result of a `~' operator. This comparison will always fail.
3332 Also warn if one operand is a constant, and the constant does not
3333 have all bits set that are set in the ~ operand when it is
3336 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3337 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3339 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3340 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3341 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3342 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3344 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3347 HOST_WIDE_INT constant, mask;
3351 if (host_integerp (primop0, 0))
3354 unsignedp = unsignedp1;
3355 constant = tree_low_cst (primop0, 0);
3360 unsignedp = unsignedp0;
3361 constant = tree_low_cst (primop1, 0);
3364 bits = TYPE_PRECISION (TREE_TYPE (primop));
3365 if (bits < TYPE_PRECISION (result_type)
3366 && bits < HOST_BITS_PER_LONG && unsignedp)
3368 mask = (~ (HOST_WIDE_INT) 0) << bits;
3369 if ((mask & constant) != mask)
3370 warning ("comparison of promoted ~unsigned with constant");
3373 else if (unsignedp0 && unsignedp1
3374 && (TYPE_PRECISION (TREE_TYPE (primop0))
3375 < TYPE_PRECISION (result_type))
3376 && (TYPE_PRECISION (TREE_TYPE (primop1))
3377 < TYPE_PRECISION (result_type)))
3378 warning ("comparison of promoted ~unsigned with unsigned");
3383 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
3384 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3385 Then the expression will be built.
3386 It will be given type FINAL_TYPE if that is nonzero;
3387 otherwise, it will be given type RESULT_TYPE. */
3391 error ("invalid operands of types `%T' and `%T' to binary `%O'",
3392 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3393 return error_mark_node;
3396 /* Issue warnings about peculiar, but valid, uses of NULL. */
3397 if (/* It's reasonable to use pointer values as operands of &&
3398 and ||, so NULL is no exception. */
3399 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3400 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3401 (orig_op0 == null_node
3402 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3403 /* Or vice versa. */
3404 || (orig_op1 == null_node
3405 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3406 /* Or, both are NULL and the operation was not a comparison. */
3407 || (orig_op0 == null_node && orig_op1 == null_node
3408 && code != EQ_EXPR && code != NE_EXPR)))
3409 /* Some sort of arithmetic operation involving NULL was
3410 performed. Note that pointer-difference and pointer-addition
3411 have already been handled above, and so we don't end up here in
3413 warning ("NULL used in arithmetic");
3417 if (TREE_TYPE (op0) != result_type)
3418 op0 = cp_convert (result_type, op0);
3419 if (TREE_TYPE (op1) != result_type)
3420 op1 = cp_convert (result_type, op1);
3422 if (op0 == error_mark_node || op1 == error_mark_node)
3423 return error_mark_node;
3426 if (build_type == NULL_TREE)
3427 build_type = result_type;
3430 tree result = build (resultcode, build_type, op0, op1);
3433 folded = fold (result);
3434 if (folded == result)
3435 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
3436 if (final_type != 0)
3437 return cp_convert (final_type, folded);
3442 /* Return a tree for the sum or difference (RESULTCODE says which)
3443 of pointer PTROP and integer INTOP. */
3446 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3448 tree res_type = TREE_TYPE (ptrop);
3450 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3451 in certain circumstance (when it's valid to do so). So we need
3452 to make sure it's complete. We don't need to check here, if we
3453 can actually complete it at all, as those checks will be done in
3454 pointer_int_sum() anyway. */
3455 complete_type (TREE_TYPE (res_type));
3457 return pointer_int_sum (resultcode, ptrop, fold (intop));
3460 /* Return a tree for the difference of pointers OP0 and OP1.
3461 The resulting tree has type int. */
3464 pointer_diff (tree op0, tree op1, tree ptrtype)
3466 tree result, folded;
3467 tree restype = ptrdiff_type_node;
3468 tree target_type = TREE_TYPE (ptrtype);
3470 if (!complete_type_or_else (target_type, NULL_TREE))
3471 return error_mark_node;
3473 if (pedantic || warn_pointer_arith)
3475 if (TREE_CODE (target_type) == VOID_TYPE)
3476 pedwarn ("ISO C++ forbids using pointer of type `void *' in subtraction");
3477 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3478 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3479 if (TREE_CODE (target_type) == METHOD_TYPE)
3480 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3483 /* First do the subtraction as integers;
3484 then drop through to build the divide operator. */
3486 op0 = cp_build_binary_op (MINUS_EXPR,
3487 cp_convert (restype, op0),
3488 cp_convert (restype, op1));
3490 /* This generates an error if op1 is a pointer to an incomplete type. */
3491 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3492 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3494 op1 = (TYPE_PTROB_P (ptrtype)
3495 ? size_in_bytes (target_type)
3496 : integer_one_node);
3498 /* Do the division. */
3500 result = build (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3502 folded = fold (result);
3503 if (folded == result)
3504 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
3508 /* Construct and perhaps optimize a tree representation
3509 for a unary operation. CODE, a tree_code, specifies the operation
3510 and XARG is the operand. */
3513 build_x_unary_op (enum tree_code code, tree xarg)
3515 tree orig_expr = xarg;
3519 if (processing_template_decl)
3521 if (type_dependent_expression_p (xarg))
3522 return build_min_nt (code, xarg, NULL_TREE);
3523 xarg = build_non_dependent_expr (xarg);
3528 /* & rec, on incomplete RECORD_TYPEs is the simple opr &, not an
3530 if (code == ADDR_EXPR
3531 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3532 && ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (xarg)))
3533 && !COMPLETE_TYPE_P (TREE_TYPE (xarg)))
3534 || (TREE_CODE (xarg) == OFFSET_REF)))
3535 /* Don't look for a function. */;
3537 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
3538 /*overloaded_p=*/NULL);
3539 if (!exp && code == ADDR_EXPR)
3541 /* A pointer to member-function can be formed only by saying
3543 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3544 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3546 if (TREE_CODE (xarg) != OFFSET_REF)
3548 error ("invalid use of '%E' to form a pointer-to-member-function. Use a qualified-id.",
3550 return error_mark_node;
3554 error ("parenthesis around '%E' cannot be used to form a pointer-to-member-function",
3556 PTRMEM_OK_P (xarg) = 1;
3560 if (TREE_CODE (xarg) == OFFSET_REF)
3562 ptrmem = PTRMEM_OK_P (xarg);
3564 if (!ptrmem && !flag_ms_extensions
3565 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3567 /* A single non-static member, make sure we don't allow a
3568 pointer-to-member. */
3569 xarg = build (OFFSET_REF, TREE_TYPE (xarg),
3570 TREE_OPERAND (xarg, 0),
3571 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3572 PTRMEM_OK_P (xarg) = ptrmem;
3575 else if (TREE_CODE (xarg) == TARGET_EXPR)
3576 warning ("taking address of temporary");
3577 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3578 if (TREE_CODE (exp) == ADDR_EXPR)
3579 PTRMEM_OK_P (exp) = ptrmem;
3582 if (processing_template_decl && exp != error_mark_node)
3583 return build_min_non_dep (code, exp, orig_expr,
3584 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3588 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3589 constants, where a null value is represented by an INTEGER_CST of
3593 cp_truthvalue_conversion (tree expr)
3595 tree type = TREE_TYPE (expr);
3596 if (TYPE_PTRMEM_P (type))
3597 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3599 return c_common_truthvalue_conversion (expr);
3602 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3605 condition_conversion (tree expr)
3608 if (processing_template_decl)
3610 t = perform_implicit_conversion (boolean_type_node, expr);
3611 t = fold (build1 (CLEANUP_POINT_EXPR, boolean_type_node, t));
3615 /* Return an ADDR_EXPR giving the address of T. This function
3616 attempts no optimizations or simplifications; it is a low-level
3620 build_address (tree t)
3624 if (error_operand_p (t) || !cxx_mark_addressable (t))
3625 return error_mark_node;
3627 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3629 TREE_CONSTANT (addr) = 1;
3634 /* Return a NOP_EXPR converting EXPR to TYPE. */
3637 build_nop (tree type, tree expr)
3641 if (type == error_mark_node || error_operand_p (expr))
3644 nop = build1 (NOP_EXPR, type, expr);
3645 if (TREE_CONSTANT (expr))
3646 TREE_CONSTANT (nop) = 1;
3651 /* C++: Must handle pointers to members.
3653 Perhaps type instantiation should be extended to handle conversion
3654 from aggregates to types we don't yet know we want? (Or are those
3655 cases typically errors which should be reported?)
3657 NOCONVERT nonzero suppresses the default promotions
3658 (such as from short to int). */
3661 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3663 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3666 const char *errstring = NULL;
3669 if (arg == error_mark_node)
3670 return error_mark_node;
3675 /* This is used for unary plus, because a CONVERT_EXPR
3676 is enough to prevent anybody from looking inside for
3677 associativity, but won't generate any code. */
3678 if (!(arg = build_expr_type_conversion
3679 (WANT_ARITH | WANT_ENUM | WANT_POINTER, arg, true)))
3680 errstring = "wrong type argument to unary plus";
3684 arg = default_conversion (arg);
3685 arg = build1 (NON_LVALUE_EXPR, TREE_TYPE (arg), arg);
3686 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3691 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3692 errstring = "wrong type argument to unary minus";
3693 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3694 arg = perform_integral_promotions (arg);
3698 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3702 arg = default_conversion (arg);
3704 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
3706 errstring = "wrong type argument to bit-complement";
3707 else if (!noconvert)
3708 arg = perform_integral_promotions (arg);
3712 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3713 errstring = "wrong type argument to abs";
3714 else if (!noconvert)
3715 arg = default_conversion (arg);
3719 /* Conjugating a real value is a no-op, but allow it anyway. */
3720 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3721 errstring = "wrong type argument to conjugation";
3722 else if (!noconvert)
3723 arg = default_conversion (arg);
3726 case TRUTH_NOT_EXPR:
3727 arg = perform_implicit_conversion (boolean_type_node, arg);
3728 val = invert_truthvalue (arg);
3729 if (arg != error_mark_node)
3731 errstring = "in argument to unary !";
3738 if (TREE_CODE (arg) == COMPLEX_CST)
3739 return TREE_REALPART (arg);
3740 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3741 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3746 if (TREE_CODE (arg) == COMPLEX_CST)
3747 return TREE_IMAGPART (arg);
3748 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3749 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3751 return cp_convert (TREE_TYPE (arg), integer_zero_node);
3753 case PREINCREMENT_EXPR:
3754 case POSTINCREMENT_EXPR:
3755 case PREDECREMENT_EXPR:
3756 case POSTDECREMENT_EXPR:
3757 /* Handle complex lvalues (when permitted)
3758 by reduction to simpler cases. */
3760 val = unary_complex_lvalue (code, arg);
3764 /* Increment or decrement the real part of the value,
3765 and don't change the imaginary part. */
3766 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3770 arg = stabilize_reference (arg);
3771 real = build_unary_op (REALPART_EXPR, arg, 1);
3772 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
3773 return build (COMPLEX_EXPR, TREE_TYPE (arg),
3774 build_unary_op (code, real, 1), imag);
3777 /* Report invalid types. */
3779 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
3782 if (code == PREINCREMENT_EXPR)
3783 errstring ="no pre-increment operator for type";
3784 else if (code == POSTINCREMENT_EXPR)
3785 errstring ="no post-increment operator for type";
3786 else if (code == PREDECREMENT_EXPR)
3787 errstring ="no pre-decrement operator for type";
3789 errstring ="no post-decrement operator for type";
3793 /* Report something read-only. */
3795 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
3796 || TREE_READONLY (arg))
3797 readonly_error (arg, ((code == PREINCREMENT_EXPR
3798 || code == POSTINCREMENT_EXPR)
3799 ? "increment" : "decrement"),
3804 tree result_type = TREE_TYPE (arg);
3806 arg = get_unwidened (arg, 0);
3807 argtype = TREE_TYPE (arg);
3809 /* ARM $5.2.5 last annotation says this should be forbidden. */
3810 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
3811 pedwarn ("ISO C++ forbids %sing an enum",
3812 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3813 ? "increment" : "decrement");
3815 /* Compute the increment. */
3817 if (TREE_CODE (argtype) == POINTER_TYPE)
3819 tree type = complete_type (TREE_TYPE (argtype));
3821 if (!COMPLETE_OR_VOID_TYPE_P (type))
3822 error ("cannot %s a pointer to incomplete type `%T'",
3823 ((code == PREINCREMENT_EXPR
3824 || code == POSTINCREMENT_EXPR)
3825 ? "increment" : "decrement"), TREE_TYPE (argtype));
3826 else if ((pedantic || warn_pointer_arith)
3827 && !TYPE_PTROB_P (argtype))
3828 pedwarn ("ISO C++ forbids %sing a pointer of type `%T'",
3829 ((code == PREINCREMENT_EXPR
3830 || code == POSTINCREMENT_EXPR)
3831 ? "increment" : "decrement"), argtype);
3832 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
3835 inc = integer_one_node;
3837 inc = cp_convert (argtype, inc);
3839 /* Handle incrementing a cast-expression. */
3841 switch (TREE_CODE (arg))
3846 case FIX_TRUNC_EXPR:
3847 case FIX_FLOOR_EXPR:
3848 case FIX_ROUND_EXPR:
3851 tree incremented, modify, value, compound;
3852 if (! lvalue_p (arg) && pedantic)
3853 pedwarn ("cast to non-reference type used as lvalue");
3854 arg = stabilize_reference (arg);
3855 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
3858 value = save_expr (arg);
3859 incremented = build (((code == PREINCREMENT_EXPR
3860 || code == POSTINCREMENT_EXPR)
3861 ? PLUS_EXPR : MINUS_EXPR),
3862 argtype, value, inc);
3864 modify = build_modify_expr (arg, NOP_EXPR, incremented);
3865 compound = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
3867 /* Eliminate warning about unused result of + or -. */
3868 TREE_NO_UNUSED_WARNING (compound) = 1;
3876 /* Complain about anything else that is not a true lvalue. */
3877 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
3878 || code == POSTINCREMENT_EXPR)
3879 ? "increment" : "decrement")))
3880 return error_mark_node;
3882 /* Forbid using -- on `bool'. */
3883 if (TREE_TYPE (arg) == boolean_type_node)
3885 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
3887 error ("invalid use of `--' on bool variable `%D'", arg);
3888 return error_mark_node;
3890 val = boolean_increment (code, arg);
3893 val = build (code, TREE_TYPE (arg), arg, inc);
3895 TREE_SIDE_EFFECTS (val) = 1;
3896 return cp_convert (result_type, val);
3900 /* Note that this operation never does default_conversion
3901 regardless of NOCONVERT. */
3903 argtype = lvalue_type (arg);
3905 if (TREE_CODE (arg) == OFFSET_REF)
3908 if (TREE_CODE (argtype) == REFERENCE_TYPE)
3912 build_pointer_type (TREE_TYPE (argtype)), arg);
3913 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3916 else if (pedantic && DECL_MAIN_P (arg))
3918 pedwarn ("ISO C++ forbids taking address of function `::main'");
3920 /* Let &* cancel out to simplify resulting code. */
3921 if (TREE_CODE (arg) == INDIRECT_REF)
3923 /* We don't need to have `current_class_ptr' wrapped in a
3924 NON_LVALUE_EXPR node. */
3925 if (arg == current_class_ref)
3926 return current_class_ptr;
3928 arg = TREE_OPERAND (arg, 0);
3929 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
3933 build_pointer_type (TREE_TYPE (TREE_TYPE (arg))), arg);
3934 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3936 else if (lvalue_p (arg))
3937 /* Don't let this be an lvalue. */
3938 return non_lvalue (arg);
3942 /* For &x[y], return x+y. */
3943 if (TREE_CODE (arg) == ARRAY_REF)
3945 if (!cxx_mark_addressable (TREE_OPERAND (arg, 0)))
3946 return error_mark_node;
3947 return cp_build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
3948 TREE_OPERAND (arg, 1));
3951 /* Uninstantiated types are all functions. Taking the
3952 address of a function is a no-op, so just return the
3955 if (TREE_CODE (arg) == IDENTIFIER_NODE
3956 && IDENTIFIER_OPNAME_P (arg))
3959 /* We don't know the type yet, so just work around the problem.
3960 We know that this will resolve to an lvalue. */
3961 return build1 (ADDR_EXPR, unknown_type_node, arg);
3964 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
3965 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
3967 /* They're trying to take the address of a unique non-static
3968 member function. This is ill-formed (except in MS-land),
3969 but let's try to DTRT.
3970 Note: We only handle unique functions here because we don't
3971 want to complain if there's a static overload; non-unique
3972 cases will be handled by instantiate_type. But we need to
3973 handle this case here to allow casts on the resulting PMF.
3974 We could defer this in non-MS mode, but it's easier to give
3975 a useful error here. */
3977 /* Inside constant member functions, the `this' pointer
3978 contains an extra const qualifier. TYPE_MAIN_VARIANT
3979 is used here to remove this const from the diagnostics
3980 and the created OFFSET_REF. */
3981 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
3982 tree name = DECL_NAME (get_first_fn (TREE_OPERAND (arg, 1)));
3984 if (! flag_ms_extensions)
3986 if (current_class_type
3987 && TREE_OPERAND (arg, 0) == current_class_ref)
3988 /* An expression like &memfn. */
3989 pedwarn ("ISO C++ forbids taking the address of an unqualified"
3990 " or parenthesized non-static member function to form"
3991 " a pointer to member function. Say `&%T::%D'",
3994 pedwarn ("ISO C++ forbids taking the address of a bound member"
3995 " function to form a pointer to member function."
3999 arg = build_offset_ref (base, name, /*address_p=*/true);
4003 if (type_unknown_p (arg))
4004 return build1 (ADDR_EXPR, unknown_type_node, arg);
4006 /* Handle complex lvalues (when permitted)
4007 by reduction to simpler cases. */
4008 val = unary_complex_lvalue (code, arg);
4012 switch (TREE_CODE (arg))
4017 case FIX_TRUNC_EXPR:
4018 case FIX_FLOOR_EXPR:
4019 case FIX_ROUND_EXPR:
4021 if (! lvalue_p (arg) && pedantic)
4022 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4029 /* Allow the address of a constructor if all the elements
4031 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_HAS_CONSTRUCTOR (arg)
4032 && TREE_CONSTANT (arg))
4034 /* Anything not already handled and not a true memory reference
4036 else if (TREE_CODE (argtype) != FUNCTION_TYPE
4037 && TREE_CODE (argtype) != METHOD_TYPE
4038 && !lvalue_or_else (arg, "unary `&'"))
4039 return error_mark_node;
4041 if (argtype != error_mark_node)
4042 argtype = build_pointer_type (argtype);
4047 if (TREE_CODE (arg) != COMPONENT_REF)
4048 addr = build_address (arg);
4049 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4051 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4053 /* We can only get here with a single static member
4055 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL
4056 && DECL_STATIC_FUNCTION_P (fn),
4059 addr = build_address (fn);
4060 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4061 /* Do not lose object's side effects. */
4062 addr = build (COMPOUND_EXPR, TREE_TYPE (addr),
4063 TREE_OPERAND (arg, 0), addr);
4065 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4067 error ("attempt to take address of bit-field structure member `%D'",
4068 TREE_OPERAND (arg, 1));
4069 return error_mark_node;
4073 /* Unfortunately we cannot just build an address
4074 expression here, because we would not handle
4075 address-constant-expressions or offsetof correctly. */
4076 tree field = TREE_OPERAND (arg, 1);
4077 tree rval = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
4078 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (rval)),
4079 decl_type_context (field),
4082 rval = build_base_path (PLUS_EXPR, rval, binfo, 1);
4083 rval = build_nop (argtype, rval);
4084 addr = fold (build (PLUS_EXPR, argtype, rval,
4085 cp_convert (argtype, byte_position (field))));
4088 if (TREE_CODE (argtype) == POINTER_TYPE
4089 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4091 build_ptrmemfunc_type (argtype);
4092 addr = build_ptrmemfunc (argtype, addr, 0);
4105 argtype = TREE_TYPE (arg);
4106 return fold (build1 (code, argtype, arg));
4109 error ("%s", errstring);
4110 return error_mark_node;
4113 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4114 for certain kinds of expressions which are not really lvalues
4115 but which we can accept as lvalues.
4117 If ARG is not a kind of expression we can handle, return zero. */
4120 unary_complex_lvalue (enum tree_code code, tree arg)
4122 /* Handle (a, b) used as an "lvalue". */
4123 if (TREE_CODE (arg) == COMPOUND_EXPR)
4125 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4126 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
4127 TREE_OPERAND (arg, 0), real_result);
4130 /* Handle (a ? b : c) used as an "lvalue". */
4131 if (TREE_CODE (arg) == COND_EXPR
4132 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4133 return rationalize_conditional_expr (code, arg);
4135 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4136 if (TREE_CODE (arg) == MODIFY_EXPR
4137 || TREE_CODE (arg) == PREINCREMENT_EXPR
4138 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4140 tree lvalue = TREE_OPERAND (arg, 0);
4141 if (TREE_SIDE_EFFECTS (lvalue))
4143 lvalue = stabilize_reference (lvalue);
4144 arg = build (TREE_CODE (arg), TREE_TYPE (arg),
4145 lvalue, TREE_OPERAND (arg, 1));
4147 return unary_complex_lvalue
4148 (code, build (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4151 if (code != ADDR_EXPR)
4154 /* Handle (a = b) used as an "lvalue" for `&'. */
4155 if (TREE_CODE (arg) == MODIFY_EXPR
4156 || TREE_CODE (arg) == INIT_EXPR)
4158 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4159 arg = build (COMPOUND_EXPR, TREE_TYPE (real_result), arg, real_result);
4160 TREE_NO_UNUSED_WARNING (arg) = 1;
4164 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4165 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4166 || TREE_CODE (arg) == OFFSET_REF)
4170 my_friendly_assert (TREE_CODE (arg) != SCOPE_REF, 313);
4172 if (TREE_CODE (arg) != OFFSET_REF)
4175 t = TREE_OPERAND (arg, 1);
4177 /* Check all this code for right semantics. */
4178 if (TREE_CODE (t) == FUNCTION_DECL)
4180 if (DECL_DESTRUCTOR_P (t))
4181 error ("taking address of destructor");
4182 return build_unary_op (ADDR_EXPR, t, 0);
4184 if (TREE_CODE (t) == VAR_DECL)
4185 return build_unary_op (ADDR_EXPR, t, 0);
4190 if (TREE_OPERAND (arg, 0)
4191 && ! is_dummy_object (TREE_OPERAND (arg, 0))
4192 && TREE_CODE (t) != FIELD_DECL)
4194 error ("taking address of bound pointer-to-member expression");
4195 return error_mark_node;
4197 if (!PTRMEM_OK_P (arg))
4198 return build_unary_op (code, arg, 0);
4200 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4202 error ("cannot create pointer to reference member `%D'", t);
4203 return error_mark_node;
4206 type = build_ptrmem_type (DECL_FIELD_CONTEXT (t), TREE_TYPE (t));
4207 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4213 /* We permit compiler to make function calls returning
4214 objects of aggregate type look like lvalues. */
4218 if (TREE_CODE (targ) == SAVE_EXPR)
4219 targ = TREE_OPERAND (targ, 0);
4221 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4223 if (TREE_CODE (arg) == SAVE_EXPR)
4226 targ = build_cplus_new (TREE_TYPE (arg), arg);
4227 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4230 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4231 return build (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4232 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4235 /* Don't let anything else be handled specially. */
4239 /* Mark EXP saying that we need to be able to take the
4240 address of it; it should not be allocated in a register.
4241 Value is true if successful.
4243 C++: we do not allow `current_class_ptr' to be addressable. */
4246 cxx_mark_addressable (tree exp)
4251 switch (TREE_CODE (x))
4258 x = TREE_OPERAND (x, 0);
4262 if (x == current_class_ptr)
4264 error ("cannot take the address of `this', which is an rvalue expression");
4265 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4271 /* Caller should not be trying to mark initialized
4272 constant fields addressable. */
4273 my_friendly_assert (DECL_LANG_SPECIFIC (x) == 0
4274 || DECL_IN_AGGR_P (x) == 0
4276 || DECL_EXTERNAL (x), 314);
4281 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4282 && !DECL_ARTIFICIAL (x) && extra_warnings)
4283 warning ("address requested for `%D', which is declared `register'",
4285 TREE_ADDRESSABLE (x) = 1;
4286 put_var_into_stack (x, /*rescan=*/true);
4290 TREE_ADDRESSABLE (x) = 1;
4291 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
4295 TREE_ADDRESSABLE (x) = 1;
4299 TREE_ADDRESSABLE (x) = 1;
4300 cxx_mark_addressable (TREE_OPERAND (x, 0));
4308 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4311 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4313 tree orig_ifexp = ifexp;
4314 tree orig_op1 = op1;
4315 tree orig_op2 = op2;
4318 if (processing_template_decl)
4320 /* The standard says that the expression is type-dependent if
4321 IFEXP is type-dependent, even though the eventual type of the
4322 expression doesn't dependent on IFEXP. */
4323 if (type_dependent_expression_p (ifexp)
4324 /* As a GNU extension, the middle operand may be omitted. */
4325 || (op1 && type_dependent_expression_p (op1))
4326 || type_dependent_expression_p (op2))
4327 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4328 ifexp = build_non_dependent_expr (ifexp);
4330 op1 = build_non_dependent_expr (op1);
4331 op2 = build_non_dependent_expr (op2);
4334 expr = build_conditional_expr (ifexp, op1, op2);
4335 if (processing_template_decl && expr != error_mark_node)
4336 return build_min_non_dep (COND_EXPR, expr,
4337 orig_ifexp, orig_op1, orig_op2);
4341 /* Given a list of expressions, return a compound expression
4342 that performs them all and returns the value of the last of them. */
4344 tree build_x_compound_expr_from_list (tree list, const char *msg)
4346 tree expr = TREE_VALUE (list);
4348 if (TREE_CHAIN (list))
4351 pedwarn ("%s expression list treated as compound expression", msg);
4353 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4354 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4360 /* Handle overloading of the ',' operator when needed. */
4363 build_x_compound_expr (tree op1, tree op2)
4366 tree orig_op1 = op1;
4367 tree orig_op2 = op2;
4369 if (processing_template_decl)
4371 if (type_dependent_expression_p (op1)
4372 || type_dependent_expression_p (op2))
4373 return build_min_nt (COMPOUND_EXPR, op1, op2);
4374 op1 = build_non_dependent_expr (op1);
4375 op2 = build_non_dependent_expr (op2);
4378 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4379 /*overloaded_p=*/NULL);
4381 result = build_compound_expr (op1, op2);
4383 if (processing_template_decl && result != error_mark_node)
4384 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4389 /* Build a compound expression. */
4392 build_compound_expr (tree lhs, tree rhs)
4394 lhs = decl_constant_value (lhs);
4395 lhs = convert_to_void (lhs, "left-hand operand of comma");
4397 if (lhs == error_mark_node || rhs == error_mark_node)
4398 return error_mark_node;
4400 if (TREE_CODE (rhs) == TARGET_EXPR)
4402 /* If the rhs is a TARGET_EXPR, then build the compound
4403 expression inside the target_expr's initializer. This
4404 helps the compiler to eliminate unnecessary temporaries. */
4405 tree init = TREE_OPERAND (rhs, 1);
4407 init = build (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4408 TREE_OPERAND (rhs, 1) = init;
4413 return build (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4416 /* Issue an error message if casting from SRC_TYPE to DEST_TYPE casts
4417 away constness. DESCRIPTION explains what operation is taking
4421 check_for_casting_away_constness (tree src_type, tree dest_type,
4422 const char *description)
4424 if (casts_away_constness (src_type, dest_type))
4425 error ("%s from type `%T' to type `%T' casts away constness",
4426 description, src_type, dest_type);
4429 /* Return an expression representing static_cast<TYPE>(EXPR). */
4432 build_static_cast (tree type, tree expr)
4437 if (type == error_mark_node || expr == error_mark_node)
4438 return error_mark_node;
4440 if (processing_template_decl)
4442 expr = build_min (STATIC_CAST_EXPR, type, expr);
4443 /* We don't know if it will or will not have side effects. */
4444 TREE_SIDE_EFFECTS (expr) = 1;
4448 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4449 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4450 if (TREE_CODE (type) != REFERENCE_TYPE
4451 && TREE_CODE (expr) == NOP_EXPR
4452 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4453 expr = TREE_OPERAND (expr, 0);
4455 intype = TREE_TYPE (expr);
4457 /* [expr.static.cast]
4459 An lvalue of type "cv1 B", where B is a class type, can be cast
4460 to type "reference to cv2 D", where D is a class derived (clause
4461 _class.derived_) from B, if a valid standard conversion from
4462 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4463 same cv-qualification as, or greater cv-qualification than, cv1,
4464 and B is not a virtual base class of D. */
4465 /* We check this case before checking the validity of "TYPE t =
4466 EXPR;" below because for this case:
4469 struct D : public B { D(const B&); };
4471 void f() { static_cast<const D&>(b); }
4473 we want to avoid constructing a new D. The standard is not
4474 completely clear about this issue, but our interpretation is
4475 consistent with other compilers. */
4476 if (TREE_CODE (type) == REFERENCE_TYPE
4477 && CLASS_TYPE_P (TREE_TYPE (type))
4478 && CLASS_TYPE_P (intype)
4479 && real_lvalue_p (expr)
4480 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4481 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4482 build_pointer_type (TYPE_MAIN_VARIANT
4483 (TREE_TYPE (type))))
4484 && at_least_as_qualified_p (TREE_TYPE (type), intype))
4486 /* There is a standard conversion from "D*" to "B*" even if "B"
4487 is ambiguous or inaccessible. Therefore, we ask lookup_base
4488 to check these conditions. */
4489 tree base = lookup_base (TREE_TYPE (type), intype, ba_check, NULL);
4491 /* Convert from "B*" to "D*". This function will check that "B"
4492 is not a virtual base of "D". */
4493 expr = build_base_path (MINUS_EXPR, build_address (expr),
4494 base, /*nonnull=*/false);
4495 /* Convert the pointer to a reference -- but then remember that
4496 there are no expressions with reference type in C++. */
4497 return convert_from_reference (build_nop (type, expr));
4500 /* [expr.static.cast]
4502 An expression e can be explicitly converted to a type T using a
4503 static_cast of the form static_cast<T>(e) if the declaration T
4504 t(e);" is well-formed, for some invented temporary variable
4506 result = perform_direct_initialization_if_possible (type, expr);
4508 return convert_from_reference (result);
4510 /* [expr.static.cast]
4512 Any expression can be explicitly converted to type cv void. */
4513 if (TREE_CODE (type) == VOID_TYPE)
4514 return convert_to_void (expr, /*implicit=*/NULL);
4516 /* [expr.static.cast]
4518 The inverse of any standard conversion sequence (clause _conv_),
4519 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4520 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4521 (_conv.bool_) conversions, can be performed explicitly using
4522 static_cast subject to the restriction that the explicit
4523 conversion does not cast away constness (_expr.const.cast_), and
4524 the following additional rules for specific cases: */
4525 /* For reference, the conversions not excluded are: integral
4526 promotions, floating point promotion, integral conversions,
4527 floating point conversions, floating-integral conversions,
4528 pointer conversions, and pointer to member conversions. */
4529 if ((ARITHMETIC_TYPE_P (type) && ARITHMETIC_TYPE_P (intype))
4532 A value of integral _or enumeration_ type can be explicitly
4533 converted to an enumeration type. */
4534 || (INTEGRAL_OR_ENUMERATION_TYPE_P (type)
4535 && INTEGRAL_OR_ENUMERATION_TYPE_P (intype)))
4536 /* Really, build_c_cast should defer to this function rather
4537 than the other way around. */
4538 return build_c_cast (type, expr);
4540 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4541 && CLASS_TYPE_P (TREE_TYPE (type))
4542 && CLASS_TYPE_P (TREE_TYPE (intype))
4543 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4544 (TREE_TYPE (intype))),
4545 build_pointer_type (TYPE_MAIN_VARIANT
4546 (TREE_TYPE (type)))))
4550 check_for_casting_away_constness (intype, type, "static_cast");
4551 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype), ba_check,
4553 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4556 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4557 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4564 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4565 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4567 if (TYPE_PTRMEM_P (type))
4569 t1 = (build_ptrmem_type
4571 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4572 t2 = (build_ptrmem_type
4574 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4581 if (can_convert (t1, t2))
4583 check_for_casting_away_constness (intype, type, "static_cast");
4584 if (TYPE_PTRMEM_P (type))
4588 if (TREE_CODE (expr) == PTRMEM_CST)
4589 expr = cplus_expand_constant (expr);
4590 delta = get_delta_difference (c1, c2, /*force=*/1);
4591 if (!integer_zerop (delta))
4592 expr = cp_build_binary_op (PLUS_EXPR,
4593 build_nop (ptrdiff_type_node, expr),
4595 return build_nop (type, expr);
4598 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4603 /* [expr.static.cast]
4605 An rvalue of type "pointer to cv void" can be explicitly
4606 converted to a pointer to object type. A value of type pointer
4607 to object converted to "pointer to cv void" and back to the
4608 original pointer type will have its original value. */
4609 if (TREE_CODE (intype) == POINTER_TYPE
4610 && VOID_TYPE_P (TREE_TYPE (intype))
4611 && TYPE_PTROB_P (type))
4613 check_for_casting_away_constness (intype, type, "static_cast");
4614 return build_nop (type, expr);
4617 error ("invalid static_cast from type `%T' to type `%T'", intype, type);
4618 return error_mark_node;
4622 build_reinterpret_cast (tree type, tree expr)
4626 if (type == error_mark_node || expr == error_mark_node)
4627 return error_mark_node;
4629 if (processing_template_decl)
4631 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
4633 if (!TREE_SIDE_EFFECTS (t)
4634 && type_dependent_expression_p (expr))
4635 /* There might turn out to be side effects inside expr. */
4636 TREE_SIDE_EFFECTS (t) = 1;
4640 if (TREE_CODE (type) != REFERENCE_TYPE)
4642 expr = decay_conversion (expr);
4644 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4645 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4646 if (TREE_CODE (expr) == NOP_EXPR
4647 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4648 expr = TREE_OPERAND (expr, 0);
4651 intype = TREE_TYPE (expr);
4653 if (TREE_CODE (type) == REFERENCE_TYPE)
4655 if (! real_lvalue_p (expr))
4657 error ("invalid reinterpret_cast of an rvalue expression of type `%T' to type `%T'", intype, type);
4658 return error_mark_node;
4660 expr = build_unary_op (ADDR_EXPR, expr, 0);
4661 if (expr != error_mark_node)
4662 expr = build_reinterpret_cast
4663 (build_pointer_type (TREE_TYPE (type)), expr);
4664 if (expr != error_mark_node)
4665 expr = build_indirect_ref (expr, 0);
4668 else if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4669 return build_static_cast (type, expr);
4671 if (TYPE_PTR_P (type) && (TREE_CODE (intype) == INTEGER_TYPE
4672 || TREE_CODE (intype) == ENUMERAL_TYPE))
4674 else if (TREE_CODE (type) == INTEGER_TYPE && TYPE_PTR_P (intype))
4676 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
4677 pedwarn ("reinterpret_cast from `%T' to `%T' loses precision",
4680 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
4681 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4683 expr = decl_constant_value (expr);
4684 return fold (build1 (NOP_EXPR, type, expr));
4686 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4687 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
4689 check_for_casting_away_constness (intype, type, "reinterpret_cast");
4690 expr = decl_constant_value (expr);
4691 return fold (build1 (NOP_EXPR, type, expr));
4693 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
4694 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
4696 pedwarn ("ISO C++ forbids casting between pointer-to-function and pointer-to-object");
4697 expr = decl_constant_value (expr);
4698 return fold (build1 (NOP_EXPR, type, expr));
4702 error ("invalid reinterpret_cast from type `%T' to type `%T'",
4704 return error_mark_node;
4707 return cp_convert (type, expr);
4711 build_const_cast (tree type, tree expr)
4715 if (type == error_mark_node || expr == error_mark_node)
4716 return error_mark_node;
4718 if (processing_template_decl)
4720 tree t = build_min (CONST_CAST_EXPR, type, expr);
4722 if (!TREE_SIDE_EFFECTS (t)
4723 && type_dependent_expression_p (expr))
4724 /* There might turn out to be side effects inside expr. */
4725 TREE_SIDE_EFFECTS (t) = 1;
4729 if (!POINTER_TYPE_P (type))
4730 error ("invalid use of const_cast with type `%T', which is not a pointer, reference, nor a pointer-to-data-member type", type);
4731 else if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4733 error ("invalid use of const_cast with type `%T', which is a pointer or reference to a function type", type);
4734 return error_mark_node;
4737 if (TREE_CODE (type) != REFERENCE_TYPE)
4739 expr = decay_conversion (expr);
4741 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4742 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4743 if (TREE_CODE (expr) == NOP_EXPR
4744 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4745 expr = TREE_OPERAND (expr, 0);
4748 intype = TREE_TYPE (expr);
4750 if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4751 return build_static_cast (type, expr);
4752 else if (TREE_CODE (type) == REFERENCE_TYPE)
4754 if (! real_lvalue_p (expr))
4756 error ("invalid const_cast of an rvalue of type `%T' to type `%T'", intype, type);
4757 return error_mark_node;
4760 if (comp_ptr_ttypes_const (TREE_TYPE (type), intype))
4762 expr = build_unary_op (ADDR_EXPR, expr, 0);
4763 expr = build1 (NOP_EXPR, type, expr);
4764 return convert_from_reference (expr);
4767 else if (((TREE_CODE (type) == POINTER_TYPE
4768 && TREE_CODE (intype) == POINTER_TYPE)
4769 || (TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype)))
4770 && comp_ptr_ttypes_const (TREE_TYPE (type), TREE_TYPE (intype)))
4771 return cp_convert (type, expr);
4773 error ("invalid const_cast from type `%T' to type `%T'", intype, type);
4774 return error_mark_node;
4777 /* Build an expression representing a cast to type TYPE of expression EXPR.
4779 ALLOW_NONCONVERTING is true if we should allow non-converting constructors
4780 when doing the cast. */
4783 build_c_cast (tree type, tree expr)
4788 if (type == error_mark_node || expr == error_mark_node)
4789 return error_mark_node;
4791 if (processing_template_decl)
4793 tree t = build_min (CAST_EXPR, type,
4794 tree_cons (NULL_TREE, value, NULL_TREE));
4795 /* We don't know if it will or will not have side effects. */
4796 TREE_SIDE_EFFECTS (t) = 1;
4800 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4801 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4802 if (TREE_CODE (type) != REFERENCE_TYPE
4803 && TREE_CODE (value) == NOP_EXPR
4804 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
4805 value = TREE_OPERAND (value, 0);
4807 if (TREE_CODE (type) == ARRAY_TYPE)
4809 /* Allow casting from T1* to T2[] because Cfront allows it.
4810 NIHCL uses it. It is not valid ISO C++ however. */
4811 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
4813 pedwarn ("ISO C++ forbids casting to an array type `%T'", type);
4814 type = build_pointer_type (TREE_TYPE (type));
4818 error ("ISO C++ forbids casting to an array type `%T'", type);
4819 return error_mark_node;
4823 if (TREE_CODE (type) == FUNCTION_TYPE
4824 || TREE_CODE (type) == METHOD_TYPE)
4826 error ("invalid cast to function type `%T'", type);
4827 return error_mark_node;
4830 if (TREE_CODE (type) == VOID_TYPE)
4832 /* Conversion to void does not cause any of the normal function to
4833 * pointer, array to pointer and lvalue to rvalue decays. */
4835 value = convert_to_void (value, /*implicit=*/NULL);
4839 if (!complete_type_or_else (type, NULL_TREE))
4840 return error_mark_node;
4842 /* Convert functions and arrays to pointers and
4843 convert references to their expanded types,
4844 but don't convert any other types. If, however, we are
4845 casting to a class type, there's no reason to do this: the
4846 cast will only succeed if there is a converting constructor,
4847 and the default conversions will be done at that point. In
4848 fact, doing the default conversion here is actually harmful
4852 struct S { S(const A&); };
4854 since we don't want the array-to-pointer conversion done. */
4855 if (!IS_AGGR_TYPE (type))
4857 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
4858 || (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE
4859 /* Don't do the default conversion on a ->* expression. */
4860 && ! (TREE_CODE (type) == POINTER_TYPE
4861 && bound_pmf_p (value)))
4862 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
4863 || TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4864 value = decay_conversion (value);
4866 else if (TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4867 /* However, even for class types, we still need to strip away
4868 the reference type, since the call to convert_force below
4869 does not expect the input expression to be of reference
4871 value = convert_from_reference (value);
4873 otype = TREE_TYPE (value);
4875 /* Optionally warn about potentially worrisome casts. */
4878 && TREE_CODE (type) == POINTER_TYPE
4879 && TREE_CODE (otype) == POINTER_TYPE
4880 && !at_least_as_qualified_p (TREE_TYPE (type),
4882 warning ("cast from `%T' to `%T' discards qualifiers from pointer target type",
4885 if (TREE_CODE (type) == INTEGER_TYPE
4886 && TYPE_PTR_P (otype)
4887 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
4888 warning ("cast from pointer to integer of different size");
4890 if (TYPE_PTR_P (type)
4891 && TREE_CODE (otype) == INTEGER_TYPE
4892 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
4893 /* Don't warn about converting any constant. */
4894 && !TREE_CONSTANT (value))
4895 warning ("cast to pointer from integer of different size");
4897 if (TREE_CODE (type) == REFERENCE_TYPE)
4898 value = (convert_from_reference
4899 (convert_to_reference (type, value, CONV_C_CAST,
4900 LOOKUP_COMPLAIN, NULL_TREE)));
4905 value = decl_constant_value (value);
4908 value = convert_force (type, value, CONV_C_CAST);
4910 /* Ignore any integer overflow caused by the cast. */
4911 if (TREE_CODE (value) == INTEGER_CST)
4913 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
4914 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
4918 /* Warn about possible alignment problems. Do this here when we will have
4919 instantiated any necessary template types. */
4920 if (STRICT_ALIGNMENT && warn_cast_align
4921 && TREE_CODE (type) == POINTER_TYPE
4922 && TREE_CODE (otype) == POINTER_TYPE
4923 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
4924 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
4925 && COMPLETE_TYPE_P (TREE_TYPE (otype))
4926 && COMPLETE_TYPE_P (TREE_TYPE (type))
4927 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
4928 warning ("cast from `%T' to `%T' increases required alignment of target type",
4931 /* Always produce some operator for an explicit cast,
4932 so we can tell (for -pedantic) that the cast is no lvalue. */
4933 if (TREE_CODE (type) != REFERENCE_TYPE && value == expr
4934 && real_lvalue_p (value))
4935 value = non_lvalue (value);
4940 /* Build an assignment expression of lvalue LHS from value RHS.
4941 MODIFYCODE is the code for a binary operator that we use
4942 to combine the old value of LHS with RHS to get the new value.
4943 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
4945 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
4948 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
4952 tree lhstype = TREE_TYPE (lhs);
4953 tree olhstype = lhstype;
4954 tree olhs = NULL_TREE;
4956 /* Avoid duplicate error messages from operands that had errors. */
4957 if (lhs == error_mark_node || rhs == error_mark_node)
4958 return error_mark_node;
4960 /* Handle control structure constructs used as "lvalues". */
4961 switch (TREE_CODE (lhs))
4963 /* Handle --foo = 5; as these are valid constructs in C++. */
4964 case PREDECREMENT_EXPR:
4965 case PREINCREMENT_EXPR:
4966 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4967 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4968 stabilize_reference (TREE_OPERAND (lhs, 0)),
4969 TREE_OPERAND (lhs, 1));
4970 return build (COMPOUND_EXPR, lhstype,
4972 build_modify_expr (TREE_OPERAND (lhs, 0),
4975 /* Handle (a, b) used as an "lvalue". */
4977 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
4979 if (newrhs == error_mark_node)
4980 return error_mark_node;
4981 return build (COMPOUND_EXPR, lhstype,
4982 TREE_OPERAND (lhs, 0), newrhs);
4985 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4986 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4987 stabilize_reference (TREE_OPERAND (lhs, 0)),
4988 TREE_OPERAND (lhs, 1));
4989 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
4990 if (newrhs == error_mark_node)
4991 return error_mark_node;
4992 return build (COMPOUND_EXPR, lhstype, lhs, newrhs);
4994 /* Handle (a ? b : c) used as an "lvalue". */
4997 /* Produce (a ? (b = rhs) : (c = rhs))
4998 except that the RHS goes through a save-expr
4999 so the code to compute it is only emitted once. */
5001 tree preeval = NULL_TREE;
5003 rhs = stabilize_expr (rhs, &preeval);
5005 /* Check this here to avoid odd errors when trying to convert
5006 a throw to the type of the COND_EXPR. */
5007 if (!lvalue_or_else (lhs, "assignment"))
5008 return error_mark_node;
5010 cond = build_conditional_expr
5011 (TREE_OPERAND (lhs, 0),
5012 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5013 TREE_OPERAND (lhs, 1)),
5015 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5016 TREE_OPERAND (lhs, 2)),
5019 if (cond == error_mark_node)
5021 /* Make sure the code to compute the rhs comes out
5022 before the split. */
5023 return build (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5030 if (modifycode == INIT_EXPR)
5032 if (TREE_CODE (rhs) == CONSTRUCTOR)
5034 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5035 /* Call convert to generate an error; see PR 11063. */
5036 rhs = convert (lhstype, rhs);
5037 result = build (INIT_EXPR, lhstype, lhs, rhs);
5038 TREE_SIDE_EFFECTS (result) = 1;
5041 else if (! IS_AGGR_TYPE (lhstype))
5042 /* Do the default thing. */;
5045 result = build_special_member_call (lhs, complete_ctor_identifier,
5046 build_tree_list (NULL_TREE, rhs),
5047 TYPE_BINFO (lhstype),
5049 if (result == NULL_TREE)
5050 return error_mark_node;
5056 if (TREE_CODE (lhstype) == REFERENCE_TYPE)
5058 lhs = convert_from_reference (lhs);
5059 olhstype = lhstype = TREE_TYPE (lhs);
5061 lhs = require_complete_type (lhs);
5062 if (lhs == error_mark_node)
5063 return error_mark_node;
5065 if (modifycode == NOP_EXPR)
5067 /* `operator=' is not an inheritable operator. */
5068 if (! IS_AGGR_TYPE (lhstype))
5069 /* Do the default thing. */;
5072 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5073 lhs, rhs, make_node (NOP_EXPR),
5074 /*overloaded_p=*/NULL);
5075 if (result == NULL_TREE)
5076 return error_mark_node;
5083 /* A binary op has been requested. Combine the old LHS
5084 value with the RHS producing the value we should actually
5085 store into the LHS. */
5087 my_friendly_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE),
5089 lhs = stabilize_reference (lhs);
5090 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5091 if (newrhs == error_mark_node)
5093 error (" in evaluation of `%Q(%#T, %#T)'", modifycode,
5094 TREE_TYPE (lhs), TREE_TYPE (rhs));
5095 return error_mark_node;
5098 /* Now it looks like a plain assignment. */
5099 modifycode = NOP_EXPR;
5101 my_friendly_assert (TREE_CODE (lhstype) != REFERENCE_TYPE, 20011220);
5102 my_friendly_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE,
5106 /* The left-hand side must be an lvalue. */
5107 if (!lvalue_or_else (lhs, "assignment"))
5108 return error_mark_node;
5110 /* Warn about modifying something that is `const'. Don't warn if
5111 this is initialization. */
5112 if (modifycode != INIT_EXPR
5113 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5114 /* Functions are not modifiable, even though they are
5116 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5117 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5118 /* If it's an aggregate and any field is const, then it is
5119 effectively const. */
5120 || (CLASS_TYPE_P (lhstype)
5121 && C_TYPE_FIELDS_READONLY (lhstype))))
5122 readonly_error (lhs, "assignment", 0);
5124 /* If storing into a structure or union member, it has probably been
5125 given type `int'. Compute the type that would go with the actual
5126 amount of storage the member occupies. */
5128 if (TREE_CODE (lhs) == COMPONENT_REF
5129 && (TREE_CODE (lhstype) == INTEGER_TYPE
5130 || TREE_CODE (lhstype) == REAL_TYPE
5131 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5133 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5135 /* If storing in a field that is in actuality a short or narrower
5136 than one, we must store in the field in its actual type. */
5138 if (lhstype != TREE_TYPE (lhs))
5140 /* Avoid warnings converting integral types back into enums for
5142 if (TREE_CODE (lhstype) == INTEGER_TYPE
5143 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5145 if (TREE_SIDE_EFFECTS (lhs))
5146 lhs = stabilize_reference (lhs);
5149 lhs = copy_node (lhs);
5150 TREE_TYPE (lhs) = lhstype;
5154 /* Convert new value to destination type. */
5156 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5160 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5161 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5163 error ("incompatible types in assignment of `%T' to `%T'",
5164 TREE_TYPE (rhs), lhstype);
5165 return error_mark_node;
5168 /* Allow array assignment in compiler-generated code. */
5169 if (! DECL_ARTIFICIAL (current_function_decl))
5170 pedwarn ("ISO C++ forbids assignment of arrays");
5172 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5173 ? 1 + (modifycode != INIT_EXPR): 0;
5174 return build_vec_init (lhs, NULL_TREE, newrhs, from_array);
5177 if (modifycode == INIT_EXPR)
5178 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5179 "initialization", NULL_TREE, 0);
5182 /* Avoid warnings on enum bit fields. */
5183 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5184 && TREE_CODE (lhstype) == INTEGER_TYPE)
5186 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5188 newrhs = convert_force (lhstype, newrhs, 0);
5191 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5193 if (TREE_CODE (newrhs) == CALL_EXPR
5194 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5195 newrhs = build_cplus_new (lhstype, newrhs);
5197 /* Can't initialize directly from a TARGET_EXPR, since that would
5198 cause the lhs to be constructed twice, and possibly result in
5199 accidental self-initialization. So we force the TARGET_EXPR to be
5200 expanded without a target. */
5201 if (TREE_CODE (newrhs) == TARGET_EXPR)
5202 newrhs = build (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5203 TREE_OPERAND (newrhs, 0));
5206 if (newrhs == error_mark_node)
5207 return error_mark_node;
5209 result = build (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5210 lhstype, lhs, newrhs);
5212 TREE_SIDE_EFFECTS (result) = 1;
5214 /* If we got the LHS in a different type for storing in,
5215 convert the result back to the nominal type of LHS
5216 so that the value we return always has the same type
5217 as the LHS argument. */
5219 if (olhstype == TREE_TYPE (result))
5223 result = build (COMPOUND_EXPR, olhstype, result, olhs);
5224 TREE_NO_UNUSED_WARNING (result) = 1;
5227 return convert_for_assignment (olhstype, result, "assignment",
5232 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5234 if (processing_template_decl)
5235 return build_min_nt (MODOP_EXPR, lhs,
5236 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5238 if (modifycode != NOP_EXPR)
5240 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5241 make_node (modifycode),
5242 /*overloaded_p=*/NULL);
5246 return build_modify_expr (lhs, modifycode, rhs);
5250 /* Get difference in deltas for different pointer to member function
5251 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5252 the conversion is invalid, the constant is zero. If FORCE is true,
5253 then allow reverse conversions as well.
5255 Note that the naming of FROM and TO is kind of backwards; the return
5256 value is what we add to a TO in order to get a FROM. They are named
5257 this way because we call this function to find out how to convert from
5258 a pointer to member of FROM to a pointer to member of TO. */
5261 get_delta_difference (tree from, tree to, int force)
5267 binfo = lookup_base (to, from, ba_check, &kind);
5268 if (kind == bk_inaccessible || kind == bk_ambig)
5270 error (" in pointer to member function conversion");
5277 error_not_base_type (from, to);
5278 error (" in pointer to member conversion");
5281 binfo = lookup_base (from, to, ba_check, &kind);
5284 virt_binfo = binfo_from_vbase (binfo);
5287 /* This is a reinterpret cast, we choose to do nothing. */
5288 warning ("pointer to member cast via virtual base `%T'",
5289 BINFO_TYPE (virt_binfo));
5292 return convert_to_integer (ptrdiff_type_node,
5293 size_diffop (size_zero_node,
5294 BINFO_OFFSET (binfo)));
5297 virt_binfo = binfo_from_vbase (binfo);
5299 return convert_to_integer (ptrdiff_type_node, BINFO_OFFSET (binfo));
5301 /* This is a reinterpret cast, we choose to do nothing. */
5303 warning ("pointer to member cast via virtual base `%T'",
5304 BINFO_TYPE (virt_binfo));
5306 error ("pointer to member conversion via virtual base `%T'",
5307 BINFO_TYPE (virt_binfo));
5310 return convert_to_integer(ptrdiff_type_node, integer_zero_node);
5313 /* Return a constructor for the pointer-to-member-function TYPE using
5314 the other components as specified. */
5317 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5323 /* Pull the FIELD_DECLs out of the type. */
5324 pfn_field = TYPE_FIELDS (type);
5325 delta_field = TREE_CHAIN (pfn_field);
5327 /* Make sure DELTA has the type we want. */
5328 delta = convert_and_check (delta_type_node, delta);
5330 /* Finish creating the initializer. */
5331 u = tree_cons (pfn_field, pfn,
5332 build_tree_list (delta_field, delta));
5333 u = build_constructor (type, u);
5334 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) && TREE_CONSTANT (delta);
5335 TREE_STATIC (u) = (TREE_CONSTANT (u)
5336 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5338 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5343 /* Build a constructor for a pointer to member function. It can be
5344 used to initialize global variables, local variable, or used
5345 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5348 If FORCE is nonzero, then force this conversion, even if
5349 we would rather not do it. Usually set when using an explicit
5352 Return error_mark_node, if something goes wrong. */
5355 build_ptrmemfunc (tree type, tree pfn, int force)
5361 if (error_operand_p (pfn))
5362 return error_mark_node;
5364 pfn_type = TREE_TYPE (pfn);
5365 to_type = build_ptrmemfunc_type (type);
5367 /* Handle multiple conversions of pointer to member functions. */
5368 if (TYPE_PTRMEMFUNC_P (pfn_type))
5370 tree delta = NULL_TREE;
5371 tree npfn = NULL_TREE;
5375 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn))
5376 error ("invalid conversion to type `%T' from type `%T'",
5379 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5380 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5383 /* We don't have to do any conversion to convert a
5384 pointer-to-member to its own type. But, we don't want to
5385 just return a PTRMEM_CST if there's an explicit cast; that
5386 cast should make the expression an invalid template argument. */
5387 if (TREE_CODE (pfn) != PTRMEM_CST)
5389 if (same_type_p (to_type, pfn_type))
5391 else if (integer_zerop (n))
5392 return build_reinterpret_cast (to_type, pfn);
5395 if (TREE_SIDE_EFFECTS (pfn))
5396 pfn = save_expr (pfn);
5398 /* Obtain the function pointer and the current DELTA. */
5399 if (TREE_CODE (pfn) == PTRMEM_CST)
5400 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
5403 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
5404 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
5407 /* Just adjust the DELTA field. */
5408 my_friendly_assert (TREE_TYPE (delta) == ptrdiff_type_node, 20030727);
5409 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
5410 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
5411 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
5412 return build_ptrmemfunc1 (to_type, delta, npfn);
5415 /* Handle null pointer to member function conversions. */
5416 if (integer_zerop (pfn))
5418 pfn = build_c_cast (type, integer_zero_node);
5419 return build_ptrmemfunc1 (to_type,
5424 if (type_unknown_p (pfn))
5425 return instantiate_type (type, pfn, tf_error | tf_warning);
5427 fn = TREE_OPERAND (pfn, 0);
5428 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5429 return make_ptrmem_cst (to_type, fn);
5432 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
5435 ??? There is no consistency as to the types returned for the above
5436 values. Some code acts as if it were a sizetype and some as if it were
5437 integer_type_node. */
5440 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
5442 tree type = TREE_TYPE (cst);
5443 tree fn = PTRMEM_CST_MEMBER (cst);
5444 tree ptr_class, fn_class;
5446 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5448 /* The class that the function belongs to. */
5449 fn_class = DECL_CONTEXT (fn);
5451 /* The class that we're creating a pointer to member of. */
5452 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
5454 /* First, calculate the adjustment to the function's class. */
5455 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0);
5457 if (!DECL_VIRTUAL_P (fn))
5458 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
5461 /* If we're dealing with a virtual function, we have to adjust 'this'
5462 again, to point to the base which provides the vtable entry for
5463 fn; the call will do the opposite adjustment. */
5464 tree orig_class = DECL_CONTEXT (fn);
5465 tree binfo = binfo_or_else (orig_class, fn_class);
5466 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5467 *delta, BINFO_OFFSET (binfo)));
5469 /* We set PFN to the vtable offset at which the function can be
5470 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
5471 case delta is shifted left, and then incremented). */
5472 *pfn = DECL_VINDEX (fn);
5473 *pfn = fold (build (MULT_EXPR, integer_type_node, *pfn,
5474 TYPE_SIZE_UNIT (vtable_entry_type)));
5476 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
5478 case ptrmemfunc_vbit_in_pfn:
5479 *pfn = fold (build (PLUS_EXPR, integer_type_node, *pfn,
5483 case ptrmemfunc_vbit_in_delta:
5484 *delta = fold (build (LSHIFT_EXPR, TREE_TYPE (*delta),
5485 *delta, integer_one_node));
5486 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5487 *delta, integer_one_node));
5494 *pfn = fold (build1 (NOP_EXPR, TYPE_PTRMEMFUNC_FN_TYPE (type),
5499 /* Return an expression for PFN from the pointer-to-member function
5503 pfn_from_ptrmemfunc (tree t)
5505 if (TREE_CODE (t) == PTRMEM_CST)
5510 expand_ptrmemfunc_cst (t, &delta, &pfn);
5515 return build_ptrmemfunc_access_expr (t, pfn_identifier);
5518 /* Expression EXPR is about to be implicitly converted to TYPE. Warn
5519 if this is a potentially dangerous thing to do. Returns a possibly
5523 dubious_conversion_warnings (tree type, tree expr,
5524 const char *errtype, tree fndecl, int parmnum)
5526 type = non_reference (type);
5528 /* Issue warnings about peculiar, but valid, uses of NULL. */
5529 if (ARITHMETIC_TYPE_P (type) && expr == null_node)
5532 warning ("passing NULL used for non-pointer %s %P of `%D'",
5533 errtype, parmnum, fndecl);
5535 warning ("%s to non-pointer type `%T' from NULL", errtype, type);
5538 /* Warn about assigning a floating-point type to an integer type. */
5539 if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE
5540 && TREE_CODE (type) == INTEGER_TYPE)
5543 warning ("passing `%T' for %s %P of `%D'",
5544 TREE_TYPE (expr), errtype, parmnum, fndecl);
5546 warning ("%s to `%T' from `%T'", errtype, type, TREE_TYPE (expr));
5548 /* And warn about assigning a negative value to an unsigned
5550 else if (TREE_UNSIGNED (type) && TREE_CODE (type) != BOOLEAN_TYPE)
5552 if (TREE_CODE (expr) == INTEGER_CST
5553 && TREE_NEGATED_INT (expr))
5556 warning ("passing negative value `%E' for %s %P of `%D'",
5557 expr, errtype, parmnum, fndecl);
5559 warning ("%s of negative value `%E' to `%T'",
5560 errtype, expr, type);
5563 overflow_warning (expr);
5565 if (TREE_CONSTANT (expr))
5571 /* Convert value RHS to type TYPE as preparation for an assignment to
5572 an lvalue of type TYPE. ERRTYPE is a string to use in error
5573 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
5574 are doing the conversion in order to pass the PARMNUMth argument of
5578 convert_for_assignment (tree type, tree rhs,
5579 const char *errtype, tree fndecl, int parmnum)
5582 enum tree_code coder;
5584 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
5585 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
5586 rhs = TREE_OPERAND (rhs, 0);
5588 rhstype = TREE_TYPE (rhs);
5589 coder = TREE_CODE (rhstype);
5591 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
5592 && ((*targetm.vector_opaque_p) (type)
5593 || (*targetm.vector_opaque_p) (rhstype)))
5594 return convert (type, rhs);
5596 if (rhs == error_mark_node || rhstype == error_mark_node)
5597 return error_mark_node;
5598 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
5599 return error_mark_node;
5601 /* The RHS of an assignment cannot have void type. */
5602 if (coder == VOID_TYPE)
5604 error ("void value not ignored as it ought to be");
5605 return error_mark_node;
5608 /* Simplify the RHS if possible. */
5609 if (TREE_CODE (rhs) == CONST_DECL)
5610 rhs = DECL_INITIAL (rhs);
5612 /* We do not use decl_constant_value here because of this case:
5614 const char* const s = "s";
5616 The conversion rules for a string literal are more lax than for a
5617 variable; in particular, a string literal can be converted to a
5618 "char *" but the variable "s" cannot be converted in the same
5619 way. If the conversion is allowed, the optimization should be
5620 performed while creating the converted expression. */
5624 The expression is implicitly converted (clause _conv_) to the
5625 cv-unqualified type of the left operand.
5627 We allow bad conversions here because by the time we get to this point
5628 we are committed to doing the conversion. If we end up doing a bad
5629 conversion, convert_like will complain. */
5630 if (!can_convert_arg_bad (type, rhstype, rhs))
5632 /* When -Wno-pmf-conversions is use, we just silently allow
5633 conversions from pointers-to-members to plain pointers. If
5634 the conversion doesn't work, cp_convert will complain. */
5636 && TYPE_PTR_P (type)
5637 && TYPE_PTRMEMFUNC_P (rhstype))
5638 rhs = cp_convert (strip_top_quals (type), rhs);
5641 /* If the right-hand side has unknown type, then it is an
5642 overloaded function. Call instantiate_type to get error
5644 if (rhstype == unknown_type_node)
5645 instantiate_type (type, rhs, tf_error | tf_warning);
5647 error ("cannot convert `%T' to `%T' for argument `%P' to `%D'",
5648 rhstype, type, parmnum, fndecl);
5650 error ("cannot convert `%T' to `%T' in %s", rhstype, type,
5652 return error_mark_node;
5655 return perform_implicit_conversion (strip_top_quals (type), rhs);
5658 /* Convert RHS to be of type TYPE.
5659 If EXP is nonzero, it is the target of the initialization.
5660 ERRTYPE is a string to use in error messages.
5662 Two major differences between the behavior of
5663 `convert_for_assignment' and `convert_for_initialization'
5664 are that references are bashed in the former, while
5665 copied in the latter, and aggregates are assigned in
5666 the former (operator=) while initialized in the
5669 If using constructor make sure no conversion operator exists, if one does
5670 exist, an ambiguity exists.
5672 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
5675 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
5676 const char *errtype, tree fndecl, int parmnum)
5678 enum tree_code codel = TREE_CODE (type);
5680 enum tree_code coder;
5682 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5683 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
5684 if (TREE_CODE (rhs) == NOP_EXPR
5685 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
5686 && codel != REFERENCE_TYPE)
5687 rhs = TREE_OPERAND (rhs, 0);
5689 if (rhs == error_mark_node
5690 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
5691 return error_mark_node;
5693 if (TREE_CODE (TREE_TYPE (rhs)) == REFERENCE_TYPE)
5694 rhs = convert_from_reference (rhs);
5696 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
5697 && TREE_CODE (type) != ARRAY_TYPE
5698 && (TREE_CODE (type) != REFERENCE_TYPE
5699 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
5700 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
5701 && (TREE_CODE (type) != REFERENCE_TYPE
5702 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
5703 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
5704 rhs = decay_conversion (rhs);
5706 rhstype = TREE_TYPE (rhs);
5707 coder = TREE_CODE (rhstype);
5709 if (coder == ERROR_MARK)
5710 return error_mark_node;
5712 /* We accept references to incomplete types, so we can
5713 return here before checking if RHS is of complete type. */
5715 if (codel == REFERENCE_TYPE)
5717 /* This should eventually happen in convert_arguments. */
5718 int savew = 0, savee = 0;
5721 savew = warningcount, savee = errorcount;
5722 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
5726 if (warningcount > savew)
5727 cp_warning_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5728 else if (errorcount > savee)
5729 cp_error_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5735 exp = require_complete_type (exp);
5736 if (exp == error_mark_node)
5737 return error_mark_node;
5739 rhstype = non_reference (rhstype);
5741 type = complete_type (type);
5743 if (IS_AGGR_TYPE (type))
5744 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
5746 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
5749 /* Expand an ASM statement with operands, handling output operands
5750 that are not variables or INDIRECT_REFS by transforming such
5751 cases into cases that expand_asm_operands can handle.
5753 Arguments are same as for expand_asm_operands.
5755 We don't do default conversions on all inputs, because it can screw
5756 up operands that are expected to be in memory. */
5759 c_expand_asm_operands (tree string, tree outputs, tree inputs, tree clobbers,
5760 int vol, location_t locus)
5762 int noutputs = list_length (outputs);
5764 /* o[I] is the place that output number I should be written. */
5765 tree *o = alloca (noutputs * sizeof (tree));
5768 /* Record the contents of OUTPUTS before it is modified. */
5769 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5770 o[i] = TREE_VALUE (tail);
5772 /* Generate the ASM_OPERANDS insn;
5773 store into the TREE_VALUEs of OUTPUTS some trees for
5774 where the values were actually stored. */
5775 expand_asm_operands (string, outputs, inputs, clobbers, vol, locus);
5777 /* Copy all the intermediate outputs into the specified outputs. */
5778 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5780 if (o[i] != TREE_VALUE (tail))
5782 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
5783 const0_rtx, VOIDmode, EXPAND_NORMAL);
5786 /* Restore the original value so that it's correct the next
5787 time we expand this function. */
5788 TREE_VALUE (tail) = o[i];
5790 /* Detect modification of read-only values.
5791 (Otherwise done by build_modify_expr.) */
5794 tree type = TREE_TYPE (o[i]);
5795 if (type != error_mark_node
5796 && (CP_TYPE_CONST_P (type)
5797 || (CLASS_TYPE_P (type) && C_TYPE_FIELDS_READONLY (type))))
5798 readonly_error (o[i], "modification by `asm'", 1);
5802 /* Those MODIFY_EXPRs could do autoincrements. */
5806 /* If RETVAL is the address of, or a reference to, a local variable or
5807 temporary give an appropriate warning. */
5810 maybe_warn_about_returning_address_of_local (tree retval)
5812 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
5813 tree whats_returned = retval;
5817 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
5818 whats_returned = TREE_OPERAND (whats_returned, 1);
5819 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
5820 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
5821 || TREE_CODE (whats_returned) == NOP_EXPR)
5822 whats_returned = TREE_OPERAND (whats_returned, 0);
5827 if (TREE_CODE (whats_returned) != ADDR_EXPR)
5829 whats_returned = TREE_OPERAND (whats_returned, 0);
5831 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5833 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
5834 || TREE_CODE (whats_returned) == TARGET_EXPR)
5836 warning ("returning reference to temporary");
5839 if (TREE_CODE (whats_returned) == VAR_DECL
5840 && DECL_NAME (whats_returned)
5841 && TEMP_NAME_P (DECL_NAME (whats_returned)))
5843 warning ("reference to non-lvalue returned");
5848 if (DECL_P (whats_returned)
5849 && DECL_NAME (whats_returned)
5850 && DECL_FUNCTION_SCOPE_P (whats_returned)
5851 && !(TREE_STATIC (whats_returned)
5852 || TREE_PUBLIC (whats_returned)))
5854 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5855 cp_warning_at ("reference to local variable `%D' returned",
5858 cp_warning_at ("address of local variable `%D' returned",
5864 /* Check that returning RETVAL from the current function is valid.
5865 Return an expression explicitly showing all conversions required to
5866 change RETVAL into the function return type, and to assign it to
5867 the DECL_RESULT for the function. */
5870 check_return_expr (tree retval)
5873 /* The type actually returned by the function, after any
5876 int fn_returns_value_p;
5878 /* A `volatile' function is one that isn't supposed to return, ever.
5879 (This is a G++ extension, used to get better code for functions
5880 that call the `volatile' function.) */
5881 if (TREE_THIS_VOLATILE (current_function_decl))
5882 warning ("function declared `noreturn' has a `return' statement");
5884 /* Check for various simple errors. */
5885 if (DECL_DESTRUCTOR_P (current_function_decl))
5888 error ("returning a value from a destructor");
5891 else if (DECL_CONSTRUCTOR_P (current_function_decl))
5893 if (in_function_try_handler)
5894 /* If a return statement appears in a handler of the
5895 function-try-block of a constructor, the program is ill-formed. */
5896 error ("cannot return from a handler of a function-try-block of a constructor");
5898 /* You can't return a value from a constructor. */
5899 error ("returning a value from a constructor");
5903 if (processing_template_decl)
5905 current_function_returns_value = 1;
5909 /* When no explicit return-value is given in a function with a named
5910 return value, the named return value is used. */
5911 result = DECL_RESULT (current_function_decl);
5912 valtype = TREE_TYPE (result);
5913 my_friendly_assert (valtype != NULL_TREE, 19990924);
5914 fn_returns_value_p = !VOID_TYPE_P (valtype);
5915 if (!retval && DECL_NAME (result) && fn_returns_value_p)
5918 /* Check for a return statement with no return value in a function
5919 that's supposed to return a value. */
5920 if (!retval && fn_returns_value_p)
5922 pedwarn ("return-statement with no value, in function returning '%T'",
5924 /* Clear this, so finish_function won't say that we reach the
5925 end of a non-void function (which we don't, we gave a
5927 current_function_returns_null = 0;
5929 /* Check for a return statement with a value in a function that
5930 isn't supposed to return a value. */
5931 else if (retval && !fn_returns_value_p)
5933 if (VOID_TYPE_P (TREE_TYPE (retval)))
5934 /* You can return a `void' value from a function of `void'
5935 type. In that case, we have to evaluate the expression for
5936 its side-effects. */
5937 finish_expr_stmt (retval);
5939 pedwarn ("return-statement with a value, in function "
5940 "returning 'void'");
5942 current_function_returns_null = 1;
5944 /* There's really no value to return, after all. */
5948 /* Remember that this function can sometimes return without a
5950 current_function_returns_null = 1;
5952 /* Remember that this function did return a value. */
5953 current_function_returns_value = 1;
5955 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
5956 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
5957 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
5958 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
5960 && null_ptr_cst_p (retval))
5961 warning ("`operator new' must not return NULL unless it is declared `throw()' (or -fcheck-new is in effect)");
5963 /* Effective C++ rule 15. See also start_function. */
5965 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR)
5966 && retval != current_class_ref)
5967 warning ("`operator=' should return a reference to `*this'");
5969 /* The fabled Named Return Value optimization, as per [class.copy]/15:
5971 [...] For a function with a class return type, if the expression
5972 in the return statement is the name of a local object, and the cv-
5973 unqualified type of the local object is the same as the function
5974 return type, an implementation is permitted to omit creating the tem-
5975 porary object to hold the function return value [...]
5977 So, if this is a value-returning function that always returns the same
5978 local variable, remember it.
5980 It might be nice to be more flexible, and choose the first suitable
5981 variable even if the function sometimes returns something else, but
5982 then we run the risk of clobbering the variable we chose if the other
5983 returned expression uses the chosen variable somehow. And people expect
5984 this restriction, anyway. (jason 2000-11-19)
5986 See finish_function, cxx_expand_function_start, and
5987 cp_copy_res_decl_for_inlining for other pieces of this
5990 if (fn_returns_value_p && flag_elide_constructors)
5992 if (retval != NULL_TREE
5993 && (current_function_return_value == NULL_TREE
5994 || current_function_return_value == retval)
5995 && TREE_CODE (retval) == VAR_DECL
5996 && DECL_CONTEXT (retval) == current_function_decl
5997 && ! TREE_STATIC (retval)
5998 && (DECL_ALIGN (retval)
5999 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6000 && same_type_p ((TYPE_MAIN_VARIANT
6001 (TREE_TYPE (retval))),
6003 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
6004 current_function_return_value = retval;
6006 current_function_return_value = error_mark_node;
6009 /* We don't need to do any conversions when there's nothing being
6011 if (!retval || retval == error_mark_node)
6014 /* Do any required conversions. */
6015 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6016 /* No conversions are required. */
6020 /* The type the function is declared to return. */
6021 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6023 /* First convert the value to the function's return type, then
6024 to the type of return value's location to handle the
6025 case that functype is smaller than the valtype. */
6026 retval = convert_for_initialization
6027 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6028 "return", NULL_TREE, 0);
6029 retval = convert (valtype, retval);
6031 /* If the conversion failed, treat this just like `return;'. */
6032 if (retval == error_mark_node)
6034 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6035 else if (! current_function_returns_struct
6036 && TREE_CODE (retval) == TARGET_EXPR
6037 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6038 retval = build (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6039 TREE_OPERAND (retval, 0));
6041 maybe_warn_about_returning_address_of_local (retval);
6044 /* Actually copy the value returned into the appropriate location. */
6045 if (retval && retval != result)
6046 retval = build (INIT_EXPR, TREE_TYPE (result), result, retval);
6052 /* Returns nonzero if the pointer-type FROM can be converted to the
6053 pointer-type TO via a qualification conversion. If CONSTP is -1,
6054 then we return nonzero if the pointers are similar, and the
6055 cv-qualification signature of FROM is a proper subset of that of TO.
6057 If CONSTP is positive, then all outer pointers have been
6061 comp_ptr_ttypes_real (tree to, tree from, int constp)
6063 bool to_more_cv_qualified = false;
6065 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6067 if (TREE_CODE (to) != TREE_CODE (from))
6070 if (TREE_CODE (from) == OFFSET_TYPE
6071 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6072 TYPE_OFFSET_BASETYPE (to)))
6075 /* Const and volatile mean something different for function types,
6076 so the usual checks are not appropriate. */
6077 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6079 if (!at_least_as_qualified_p (to, from))
6082 if (!at_least_as_qualified_p (from, to))
6086 to_more_cv_qualified = true;
6090 constp &= TYPE_READONLY (to);
6093 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6094 return ((constp >= 0 || to_more_cv_qualified)
6095 && same_type_ignoring_top_level_qualifiers_p (to, from));
6099 /* When comparing, say, char ** to char const **, this function takes
6100 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6101 types to this function. */
6104 comp_ptr_ttypes (tree to, tree from)
6106 return comp_ptr_ttypes_real (to, from, 1);
6109 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6110 type or inheritance-related types, regardless of cv-quals. */
6113 ptr_reasonably_similar (tree to, tree from)
6115 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6117 /* Any target type is similar enough to void. */
6118 if (TREE_CODE (to) == VOID_TYPE
6119 || TREE_CODE (from) == VOID_TYPE)
6122 if (TREE_CODE (to) != TREE_CODE (from))
6125 if (TREE_CODE (from) == OFFSET_TYPE
6126 && comptypes (TYPE_OFFSET_BASETYPE (to),
6127 TYPE_OFFSET_BASETYPE (from),
6128 COMPARE_BASE | COMPARE_DERIVED))
6131 if (TREE_CODE (to) == INTEGER_TYPE
6132 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6135 if (TREE_CODE (to) == FUNCTION_TYPE)
6138 if (TREE_CODE (to) != POINTER_TYPE)
6140 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6141 COMPARE_BASE | COMPARE_DERIVED);
6145 /* Like comp_ptr_ttypes, for const_cast. */
6148 comp_ptr_ttypes_const (tree to, tree from)
6150 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6152 if (TREE_CODE (to) != TREE_CODE (from))
6155 if (TREE_CODE (from) == OFFSET_TYPE
6156 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6157 TYPE_OFFSET_BASETYPE (to)))
6160 if (TREE_CODE (to) != POINTER_TYPE)
6161 return same_type_ignoring_top_level_qualifiers_p (to, from);
6165 /* Returns the type qualifiers for this type, including the qualifiers on the
6166 elements for an array type. */
6169 cp_type_quals (tree type)
6171 type = strip_array_types (type);
6172 if (type == error_mark_node)
6173 return TYPE_UNQUALIFIED;
6174 return TYPE_QUALS (type);
6177 /* Returns nonzero if the TYPE contains a mutable member. */
6180 cp_has_mutable_p (tree type)
6182 type = strip_array_types (type);
6184 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6187 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6188 exemplar types such that casting T1 to T2 is casting away castness
6189 if and only if there is no implicit conversion from T1 to T2. */
6192 casts_away_constness_r (tree *t1, tree *t2)
6197 /* [expr.const.cast]
6199 For multi-level pointer to members and multi-level mixed pointers
6200 and pointers to members (conv.qual), the "member" aspect of a
6201 pointer to member level is ignored when determining if a const
6202 cv-qualifier has been cast away. */
6203 if (TYPE_PTRMEM_P (*t1))
6204 *t1 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t1));
6205 if (TYPE_PTRMEM_P (*t2))
6206 *t2 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t2));
6208 /* [expr.const.cast]
6210 For two pointer types:
6212 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6213 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6216 casting from X1 to X2 casts away constness if, for a non-pointer
6217 type T there does not exist an implicit conversion (clause
6220 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6224 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6226 if (TREE_CODE (*t1) != POINTER_TYPE
6227 || TREE_CODE (*t2) != POINTER_TYPE)
6229 *t1 = cp_build_qualified_type (void_type_node,
6230 cp_type_quals (*t1));
6231 *t2 = cp_build_qualified_type (void_type_node,
6232 cp_type_quals (*t2));
6236 quals1 = cp_type_quals (*t1);
6237 quals2 = cp_type_quals (*t2);
6238 *t1 = TREE_TYPE (*t1);
6239 *t2 = TREE_TYPE (*t2);
6240 casts_away_constness_r (t1, t2);
6241 *t1 = build_pointer_type (*t1);
6242 *t2 = build_pointer_type (*t2);
6243 *t1 = cp_build_qualified_type (*t1, quals1);
6244 *t2 = cp_build_qualified_type (*t2, quals2);
6247 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6251 casts_away_constness (tree t1, tree t2)
6253 if (TREE_CODE (t2) == REFERENCE_TYPE)
6255 /* [expr.const.cast]
6257 Casting from an lvalue of type T1 to an lvalue of type T2
6258 using a reference cast casts away constness if a cast from an
6259 rvalue of type "pointer to T1" to the type "pointer to T2"
6260 casts away constness. */
6261 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6262 return casts_away_constness (build_pointer_type (t1),
6263 build_pointer_type (TREE_TYPE (t2)));
6266 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6267 /* [expr.const.cast]
6269 Casting from an rvalue of type "pointer to data member of X
6270 of type T1" to the type "pointer to data member of Y of type
6271 T2" casts away constness if a cast from an rvalue of type
6272 "pointer to T1" to the type "pointer to T2" casts away
6274 return casts_away_constness
6275 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6276 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6278 /* Casting away constness is only something that makes sense for
6279 pointer or reference types. */
6280 if (TREE_CODE (t1) != POINTER_TYPE
6281 || TREE_CODE (t2) != POINTER_TYPE)
6284 /* Top-level qualifiers don't matter. */
6285 t1 = TYPE_MAIN_VARIANT (t1);
6286 t2 = TYPE_MAIN_VARIANT (t2);
6287 casts_away_constness_r (&t1, &t2);
6288 if (!can_convert (t2, t1))
6294 /* If T is a REFERENCE_TYPE return the type to which T refers.
6295 Otherwise, return T itself. */
6298 non_reference (tree t)
6300 if (TREE_CODE (t) == REFERENCE_TYPE)