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 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 register enum tree_code code1;
583 register 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 build_type_attribute_variant (t1, attributes);
670 if (valtype == TREE_TYPE (t2) && ! p1)
671 return 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 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 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);
719 return build_type_attribute_variant (t1, attributes);
722 /* Return the common type of two types.
723 We assume that comptypes has already been done and returned 1;
724 if that isn't so, this may crash.
726 This is the type for the result of most arithmetic operations
727 if the operands have the given two types. */
730 common_type (tree t1, tree t2)
732 enum tree_code code1;
733 enum tree_code code2;
735 /* If one type is nonsense, bail. */
736 if (t1 == error_mark_node || t2 == error_mark_node)
737 return error_mark_node;
739 code1 = TREE_CODE (t1);
740 code2 = TREE_CODE (t2);
742 if ((ARITHMETIC_TYPE_P (t1) || code1 == ENUMERAL_TYPE
743 || code1 == COMPLEX_TYPE)
744 && (ARITHMETIC_TYPE_P (t2) || code2 == ENUMERAL_TYPE
745 || code2 == COMPLEX_TYPE))
746 return type_after_usual_arithmetic_conversions (t1, t2);
748 else if ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
749 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
750 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)))
751 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
757 /* Compare two exception specifier types for exactness or subsetness, if
758 allowed. Returns false for mismatch, true for match (same, or
761 [except.spec] "If a class X ... objects of class X or any class publicly
762 and unambiguously derived from X. Similarly, if a pointer type Y * ...
763 exceptions of type Y * or that are pointers to any type publicly and
764 unambiguously derived from Y. Otherwise a function only allows exceptions
765 that have the same type ..."
766 This does not mention cv qualifiers and is different to what throw
767 [except.throw] and catch [except.catch] will do. They will ignore the
768 top level cv qualifiers, and allow qualifiers in the pointer to class
771 We implement the letter of the standard. */
774 comp_except_types (tree a, tree b, bool exact)
776 if (same_type_p (a, b))
780 if (cp_type_quals (a) || cp_type_quals (b))
783 if (TREE_CODE (a) == POINTER_TYPE
784 && TREE_CODE (b) == POINTER_TYPE)
788 if (cp_type_quals (a) || cp_type_quals (b))
792 if (TREE_CODE (a) != RECORD_TYPE
793 || TREE_CODE (b) != RECORD_TYPE)
796 if (ACCESSIBLY_UNIQUELY_DERIVED_P (a, b))
802 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
803 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
804 otherwise it must be exact. Exception lists are unordered, but
805 we've already filtered out duplicates. Most lists will be in order,
806 we should try to make use of that. */
809 comp_except_specs (tree t1, tree t2, bool exact)
818 if (t1 == NULL_TREE) /* T1 is ... */
819 return t2 == NULL_TREE || !exact;
820 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
821 return t2 != NULL_TREE && !TREE_VALUE (t2);
822 if (t2 == NULL_TREE) /* T2 is ... */
824 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
827 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
828 Count how many we find, to determine exactness. For exact matching and
829 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
831 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
833 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
835 tree a = TREE_VALUE (probe);
836 tree b = TREE_VALUE (t2);
838 if (comp_except_types (a, b, exact))
840 if (probe == base && exact)
841 base = TREE_CHAIN (probe);
846 if (probe == NULL_TREE)
849 return !exact || base == NULL_TREE || length == list_length (t1);
852 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
853 [] can match [size]. */
856 comp_array_types (tree t1, tree t2, bool allow_redeclaration)
864 /* The type of the array elements must be the same. */
865 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
868 d1 = TYPE_DOMAIN (t1);
869 d2 = TYPE_DOMAIN (t2);
874 /* If one of the arrays is dimensionless, and the other has a
875 dimension, they are of different types. However, it is valid to
883 declarations for an array object can specify
884 array types that differ by the presence or absence of a major
885 array bound (_dcl.array_). */
887 return allow_redeclaration;
889 /* Check that the dimensions are the same. */
890 return (cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
891 && cp_tree_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)));
894 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
895 is a bitwise-or of the COMPARE_* flags. */
898 comptypes (tree t1, tree t2, int strict)
903 /* Suppress errors caused by previously reported errors */
904 if (t1 == error_mark_node || t2 == error_mark_node)
907 my_friendly_assert (TYPE_P (t1) && TYPE_P (t2), 20030623);
909 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
910 current instantiation. */
911 if (TREE_CODE (t1) == TYPENAME_TYPE)
913 tree resolved = resolve_typename_type (t1, /*only_current_p=*/true);
915 if (resolved != error_mark_node)
919 if (TREE_CODE (t2) == TYPENAME_TYPE)
921 tree resolved = resolve_typename_type (t2, /*only_current_p=*/true);
923 if (resolved != error_mark_node)
927 /* If either type is the internal version of sizetype, use the
929 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
931 t1 = TYPE_DOMAIN (t1);
933 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
935 t2 = TYPE_DOMAIN (t2);
937 if (TYPE_PTRMEMFUNC_P (t1))
938 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
939 if (TYPE_PTRMEMFUNC_P (t2))
940 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
942 /* Different classes of types can't be compatible. */
943 if (TREE_CODE (t1) != TREE_CODE (t2))
946 /* Qualifiers must match. */
947 if (cp_type_quals (t1) != cp_type_quals (t2))
949 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
952 /* Allow for two different type nodes which have essentially the same
953 definition. Note that we already checked for equality of the type
954 qualifiers (just above). */
956 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
959 if (!(*targetm.comp_type_attributes) (t1, t2))
962 switch (TREE_CODE (t1))
964 case TEMPLATE_TEMPLATE_PARM:
965 case BOUND_TEMPLATE_TEMPLATE_PARM:
966 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
967 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
969 if (!comp_template_parms
970 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
971 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
973 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
975 /* Don't check inheritance. */
976 strict = COMPARE_STRICT;
981 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
982 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
983 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
984 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
987 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
989 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
995 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
996 strict & ~COMPARE_REDECLARATION))
1001 case REFERENCE_TYPE:
1002 return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1006 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1008 return compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2));
1011 /* Target types must match incl. qualifiers. */
1012 return comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION));
1014 case TEMPLATE_TYPE_PARM:
1015 return (TEMPLATE_TYPE_IDX (t1) == TEMPLATE_TYPE_IDX (t2)
1016 && TEMPLATE_TYPE_LEVEL (t1) == TEMPLATE_TYPE_LEVEL (t2));
1019 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1020 TYPENAME_TYPE_FULLNAME (t2)))
1022 return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
1024 case UNBOUND_CLASS_TEMPLATE:
1025 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1027 return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
1030 return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1038 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1041 at_least_as_qualified_p (tree type1, tree type2)
1043 int q1 = cp_type_quals (type1);
1044 int q2 = cp_type_quals (type2);
1046 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1047 return (q1 & q2) == q2;
1050 /* Returns 1 if TYPE1 is more qualified than TYPE2. */
1053 more_qualified_p (tree type1, tree type2)
1055 int q1 = cp_type_quals (type1);
1056 int q2 = cp_type_quals (type2);
1058 return q1 != q2 && (q1 & q2) == q2;
1061 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1062 more cv-qualified that TYPE1, and 0 otherwise. */
1065 comp_cv_qualification (tree type1, tree type2)
1067 int q1 = cp_type_quals (type1);
1068 int q2 = cp_type_quals (type2);
1073 if ((q1 & q2) == q2)
1075 else if ((q1 & q2) == q1)
1081 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1082 subset of the cv-qualification signature of TYPE2, and the types
1083 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1086 comp_cv_qual_signature (tree type1, tree type2)
1088 if (comp_ptr_ttypes_real (type2, type1, -1))
1090 else if (comp_ptr_ttypes_real (type1, type2, -1))
1096 /* If two types share a common base type, return that basetype.
1097 If there is not a unique most-derived base type, this function
1098 returns ERROR_MARK_NODE. */
1101 common_base_type (tree tt1, tree tt2)
1103 tree best = NULL_TREE;
1106 /* If one is a baseclass of another, that's good enough. */
1107 if (UNIQUELY_DERIVED_FROM_P (tt1, tt2))
1109 if (UNIQUELY_DERIVED_FROM_P (tt2, tt1))
1112 /* Otherwise, try to find a unique baseclass of TT1
1113 that is shared by TT2, and follow that down. */
1114 for (i = CLASSTYPE_N_BASECLASSES (tt1)-1; i >= 0; i--)
1116 tree basetype = TYPE_BINFO_BASETYPE (tt1, i);
1117 tree trial = common_base_type (basetype, tt2);
1120 if (trial == error_mark_node)
1122 if (best == NULL_TREE)
1124 else if (best != trial)
1125 return error_mark_node;
1130 for (i = CLASSTYPE_N_BASECLASSES (tt2)-1; i >= 0; i--)
1132 tree basetype = TYPE_BINFO_BASETYPE (tt2, i);
1133 tree trial = common_base_type (tt1, basetype);
1136 if (trial == error_mark_node)
1138 if (best == NULL_TREE)
1140 else if (best != trial)
1141 return error_mark_node;
1147 /* Subroutines of `comptypes'. */
1149 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1150 equivalent in the sense that functions with those parameter types
1151 can have equivalent types. The two lists must be equivalent,
1152 element by element. */
1155 compparms (tree parms1, tree parms2)
1159 /* An unspecified parmlist matches any specified parmlist
1160 whose argument types don't need default promotions. */
1162 for (t1 = parms1, t2 = parms2;
1164 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1166 /* If one parmlist is shorter than the other,
1167 they fail to match. */
1170 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1177 /* Process a sizeof or alignof expression where the operand is a
1181 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1183 enum tree_code type_code;
1185 const char *op_name;
1187 my_friendly_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR, 20020720);
1188 if (type == error_mark_node)
1189 return error_mark_node;
1191 if (processing_template_decl)
1193 value = build_min (op, size_type_node, type);
1194 TREE_READONLY (value) = 1;
1198 op_name = operator_name_info[(int) op].name;
1200 type = non_reference (type);
1201 type_code = TREE_CODE (type);
1203 if (type_code == METHOD_TYPE)
1205 if (complain && (pedantic || warn_pointer_arith))
1206 pedwarn ("invalid application of `%s' to a member function", op_name);
1207 value = size_one_node;
1210 value = c_sizeof_or_alignof_type (complete_type (type), op, complain);
1215 /* Process a sizeof or alignof expression where the operand is an
1219 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op)
1221 const char *op_name = operator_name_info[(int) op].name;
1223 if (e == error_mark_node)
1224 return error_mark_node;
1226 if (processing_template_decl)
1228 e = build_min (op, size_type_node, e);
1229 TREE_SIDE_EFFECTS (e) = 0;
1230 TREE_READONLY (e) = 1;
1235 if (TREE_CODE (e) == COMPONENT_REF
1236 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1238 error ("invalid application of `%s' to a bit-field", op_name);
1241 else if (is_overloaded_fn (e))
1243 pedwarn ("ISO C++ forbids applying `%s' to an expression of function type", op_name);
1246 else if (type_unknown_p (e))
1248 cxx_incomplete_type_error (e, TREE_TYPE (e));
1254 return cxx_sizeof_or_alignof_type (e, op, true);
1258 /* Perform the conversions in [expr] that apply when an lvalue appears
1259 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1260 function-to-pointer conversions.
1262 In addition manifest constants are replaced by their values. */
1265 decay_conversion (tree exp)
1268 register enum tree_code code;
1270 type = TREE_TYPE (exp);
1271 code = TREE_CODE (type);
1273 if (code == REFERENCE_TYPE)
1275 exp = convert_from_reference (exp);
1276 type = TREE_TYPE (exp);
1277 code = TREE_CODE (type);
1280 if (type == error_mark_node)
1281 return error_mark_node;
1283 if (type_unknown_p (exp))
1285 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1286 return error_mark_node;
1289 /* Constants can be used directly unless they're not loadable. */
1290 if (TREE_CODE (exp) == CONST_DECL)
1291 exp = DECL_INITIAL (exp);
1292 /* Replace a nonvolatile const static variable with its value. We
1293 don't do this for arrays, though; we want the address of the
1294 first element of the array, not the address of the first element
1295 of its initializing constant. */
1296 else if (code != ARRAY_TYPE)
1298 exp = decl_constant_value (exp);
1299 type = TREE_TYPE (exp);
1302 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1303 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1305 if (code == VOID_TYPE)
1307 error ("void value not ignored as it ought to be");
1308 return error_mark_node;
1310 if (code == METHOD_TYPE)
1312 error ("invalid use of non-static member function");
1313 return error_mark_node;
1315 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1316 return build_unary_op (ADDR_EXPR, exp, 0);
1317 if (code == ARRAY_TYPE)
1322 if (TREE_CODE (exp) == INDIRECT_REF)
1323 return build_nop (build_pointer_type (TREE_TYPE (type)),
1324 TREE_OPERAND (exp, 0));
1326 if (TREE_CODE (exp) == COMPOUND_EXPR)
1328 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1329 return build (COMPOUND_EXPR, TREE_TYPE (op1),
1330 TREE_OPERAND (exp, 0), op1);
1334 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1336 error ("invalid use of non-lvalue array");
1337 return error_mark_node;
1340 ptrtype = build_pointer_type (TREE_TYPE (type));
1342 if (TREE_CODE (exp) == VAR_DECL)
1344 /* ??? This is not really quite correct
1345 in that the type of the operand of ADDR_EXPR
1346 is not the target type of the type of the ADDR_EXPR itself.
1347 Question is, can this lossage be avoided? */
1348 adr = build1 (ADDR_EXPR, ptrtype, exp);
1349 if (!cxx_mark_addressable (exp))
1350 return error_mark_node;
1351 TREE_CONSTANT (adr) = staticp (exp);
1352 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1355 /* This way is better for a COMPONENT_REF since it can
1356 simplify the offset for a component. */
1357 adr = build_unary_op (ADDR_EXPR, exp, 1);
1358 return cp_convert (ptrtype, adr);
1361 /* [basic.lval]: Class rvalues can have cv-qualified types; non-class
1362 rvalues always have cv-unqualified types. */
1363 if (! CLASS_TYPE_P (type))
1364 exp = cp_convert (TYPE_MAIN_VARIANT (type), exp);
1370 default_conversion (tree exp)
1372 exp = decay_conversion (exp);
1374 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1375 exp = perform_integral_promotions (exp);
1380 /* EXPR is an expression with an integral or enumeration type.
1381 Perform the integral promotions in [conv.prom], and return the
1385 perform_integral_promotions (tree expr)
1390 type = TREE_TYPE (expr);
1391 my_friendly_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type), 20030703);
1392 promoted_type = type_promotes_to (type);
1393 if (type != promoted_type)
1394 expr = cp_convert (promoted_type, expr);
1398 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1402 inline_conversion (tree exp)
1404 if (TREE_CODE (exp) == FUNCTION_DECL)
1405 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1410 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1411 decay_conversion to one. */
1414 string_conv_p (tree totype, tree exp, int warn)
1418 if (! flag_const_strings || TREE_CODE (totype) != POINTER_TYPE)
1421 t = TREE_TYPE (totype);
1422 if (!same_type_p (t, char_type_node)
1423 && !same_type_p (t, wchar_type_node))
1426 if (TREE_CODE (exp) == STRING_CST)
1428 /* Make sure that we don't try to convert between char and wchar_t. */
1429 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1434 /* Is this a string constant which has decayed to 'const char *'? */
1435 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1436 if (!same_type_p (TREE_TYPE (exp), t))
1439 if (TREE_CODE (exp) != ADDR_EXPR
1440 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1444 /* This warning is not very useful, as it complains about printf. */
1445 if (warn && warn_write_strings)
1446 warning ("deprecated conversion from string constant to `%T'", totype);
1451 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1452 can, for example, use as an lvalue. This code used to be in
1453 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1454 expressions, where we're dealing with aggregates. But now it's again only
1455 called from unary_complex_lvalue. The case (in particular) that led to
1456 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1460 rationalize_conditional_expr (enum tree_code code, tree t)
1462 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1463 the first operand is always the one to be used if both operands
1464 are equal, so we know what conditional expression this used to be. */
1465 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1468 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1469 ? LE_EXPR : GE_EXPR),
1470 TREE_OPERAND (t, 0),
1471 TREE_OPERAND (t, 1)),
1472 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1473 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1477 build_conditional_expr (TREE_OPERAND (t, 0),
1478 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1479 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1482 /* Given the TYPE of an anonymous union field inside T, return the
1483 FIELD_DECL for the field. If not found return NULL_TREE. Because
1484 anonymous unions can nest, we must also search all anonymous unions
1485 that are directly reachable. */
1488 lookup_anon_field (tree t, tree type)
1492 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1494 if (TREE_STATIC (field))
1496 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1499 /* If we find it directly, return the field. */
1500 if (DECL_NAME (field) == NULL_TREE
1501 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1506 /* Otherwise, it could be nested, search harder. */
1507 if (DECL_NAME (field) == NULL_TREE
1508 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1510 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1518 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1519 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1520 non-NULL, it indicates the path to the base used to name MEMBER.
1521 If PRESERVE_REFERENCE is true, the expression returned will have
1522 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1523 returned will have the type referred to by the reference.
1525 This function does not perform access control; that is either done
1526 earlier by the parser when the name of MEMBER is resolved to MEMBER
1527 itself, or later when overload resolution selects one of the
1528 functions indicated by MEMBER. */
1531 build_class_member_access_expr (tree object, tree member,
1532 tree access_path, bool preserve_reference)
1536 tree result = NULL_TREE;
1538 if (object == error_mark_node || member == error_mark_node)
1539 return error_mark_node;
1541 if (TREE_CODE (member) == PSEUDO_DTOR_EXPR)
1544 my_friendly_assert (DECL_P (member) || BASELINK_P (member),
1549 The type of the first expression shall be "class object" (of a
1551 object_type = TREE_TYPE (object);
1552 if (!complete_type_or_else (object_type, object))
1553 return error_mark_node;
1554 if (!CLASS_TYPE_P (object_type))
1556 error ("request for member `%D' in `%E', which is of non-class type `%T'",
1557 member, object, object_type);
1558 return error_mark_node;
1561 /* The standard does not seem to actually say that MEMBER must be a
1562 member of OBJECT_TYPE. However, that is clearly what is
1564 if (DECL_P (member))
1566 member_scope = DECL_CLASS_CONTEXT (member);
1568 if (TREE_DEPRECATED (member))
1569 warn_deprecated_use (member);
1572 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1573 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1574 presently be the anonymous union. Go outwards until we find a
1575 type related to OBJECT_TYPE. */
1576 while (ANON_AGGR_TYPE_P (member_scope)
1577 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1579 member_scope = TYPE_CONTEXT (member_scope);
1580 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1582 if (TREE_CODE (member) == FIELD_DECL)
1583 error ("invalid use of nonstatic data member '%E'", member);
1585 error ("`%D' is not a member of `%T'", member, object_type);
1586 return error_mark_node;
1589 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1590 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1591 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1593 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1595 object = build_indirect_ref (temp, NULL);
1598 /* In [expr.ref], there is an explicit list of the valid choices for
1599 MEMBER. We check for each of those cases here. */
1600 if (TREE_CODE (member) == VAR_DECL)
1602 /* A static data member. */
1604 /* If OBJECT has side-effects, they are supposed to occur. */
1605 if (TREE_SIDE_EFFECTS (object))
1606 result = build (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1608 else if (TREE_CODE (member) == FIELD_DECL)
1610 /* A non-static data member. */
1615 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1616 && integer_zerop (TREE_OPERAND (object, 0)));
1618 /* Convert OBJECT to the type of MEMBER. */
1619 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1620 TYPE_MAIN_VARIANT (member_scope)))
1625 binfo = lookup_base (access_path ? access_path : object_type,
1626 member_scope, ba_ignore, &kind);
1627 if (binfo == error_mark_node)
1628 return error_mark_node;
1630 /* It is invalid to try to get to a virtual base of a
1631 NULL object. The most common cause is invalid use of
1633 if (null_object_p && kind == bk_via_virtual)
1635 error ("invalid access to non-static data member `%D' of NULL object",
1637 error ("(perhaps the `offsetof' macro was used incorrectly)");
1638 return error_mark_node;
1641 /* Convert to the base. */
1642 object = build_base_path (PLUS_EXPR, object, binfo,
1644 /* If we found the base successfully then we should be able
1645 to convert to it successfully. */
1646 my_friendly_assert (object != error_mark_node,
1650 /* Complain about other invalid uses of offsetof, even though they will
1651 give the right answer. Note that we complain whether or not they
1652 actually used the offsetof macro, since there's no way to know at this
1653 point. So we just give a warning, instead of a pedwarn. */
1654 if (null_object_p && warn_invalid_offsetof
1655 && CLASSTYPE_NON_POD_P (object_type))
1657 warning ("invalid access to non-static data member `%D' of NULL object",
1659 warning ("(perhaps the `offsetof' macro was used incorrectly)");
1662 /* If MEMBER is from an anonymous aggregate, we have converted
1663 OBJECT so that it refers to the class containing the
1664 anonymous union. Generate a reference to the anonymous union
1665 itself, and recur to find MEMBER. */
1666 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1667 /* When this code is called from build_field_call, the
1668 object already has the type of the anonymous union.
1669 That is because the COMPONENT_REF was already
1670 constructed, and was then disassembled before calling
1671 build_field_call. After the function-call code is
1672 cleaned up, this waste can be eliminated. */
1673 && (!same_type_ignoring_top_level_qualifiers_p
1674 (TREE_TYPE (object), DECL_CONTEXT (member))))
1676 tree anonymous_union;
1678 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1679 DECL_CONTEXT (member));
1680 object = build_class_member_access_expr (object,
1682 /*access_path=*/NULL_TREE,
1683 preserve_reference);
1686 /* Compute the type of the field, as described in [expr.ref]. */
1687 type_quals = TYPE_UNQUALIFIED;
1688 member_type = TREE_TYPE (member);
1689 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1691 type_quals = (cp_type_quals (member_type)
1692 | cp_type_quals (object_type));
1694 /* A field is const (volatile) if the enclosing object, or the
1695 field itself, is const (volatile). But, a mutable field is
1696 not const, even within a const object. */
1697 if (DECL_MUTABLE_P (member))
1698 type_quals &= ~TYPE_QUAL_CONST;
1699 member_type = cp_build_qualified_type (member_type, type_quals);
1702 result = fold (build (COMPONENT_REF, member_type, object, member));
1704 /* Mark the expression const or volatile, as appropriate. Even
1705 though we've dealt with the type above, we still have to mark the
1706 expression itself. */
1707 if (type_quals & TYPE_QUAL_CONST)
1708 TREE_READONLY (result) = 1;
1709 else if (type_quals & TYPE_QUAL_VOLATILE)
1710 TREE_THIS_VOLATILE (result) = 1;
1712 else if (BASELINK_P (member))
1714 /* The member is a (possibly overloaded) member function. */
1718 /* If the MEMBER is exactly one static member function, then we
1719 know the type of the expression. Otherwise, we must wait
1720 until overload resolution has been performed. */
1721 functions = BASELINK_FUNCTIONS (member);
1722 if (TREE_CODE (functions) == FUNCTION_DECL
1723 && DECL_STATIC_FUNCTION_P (functions))
1724 type = TREE_TYPE (functions);
1726 type = unknown_type_node;
1727 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1728 base. That will happen when the function is called. */
1729 result = build (COMPONENT_REF, type, object, member);
1731 else if (TREE_CODE (member) == CONST_DECL)
1733 /* The member is an enumerator. */
1735 /* If OBJECT has side-effects, they are supposed to occur. */
1736 if (TREE_SIDE_EFFECTS (object))
1737 result = build (COMPOUND_EXPR, TREE_TYPE (result),
1742 error ("invalid use of `%D'", member);
1743 return error_mark_node;
1746 if (!preserve_reference)
1749 If E2 is declared to have type "reference to T", then ... the
1750 type of E1.E2 is T. */
1751 result = convert_from_reference (result);
1756 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1757 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1760 lookup_destructor (tree object, tree scope, tree dtor_name)
1762 tree object_type = TREE_TYPE (object);
1763 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1765 if (scope && !check_dtor_name (scope, dtor_name))
1767 error ("qualified type `%T' does not match destructor name `~%T'",
1769 return error_mark_node;
1771 if (!same_type_p (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1773 error ("destructor name `%T' does not match type `%T' of expression",
1774 dtor_type, object_type);
1775 return error_mark_node;
1777 if (!TYPE_HAS_DESTRUCTOR (object_type))
1778 return build (PSEUDO_DTOR_EXPR, void_type_node, object, scope,
1780 return lookup_member (object_type, complete_dtor_identifier,
1781 /*protect=*/1, /*want_type=*/false);
1784 /* This function is called by the parser to process a class member
1785 access expression of the form OBJECT.NAME. NAME is a node used by
1786 the parser to represent a name; it is not yet a DECL. It may,
1787 however, be a BASELINK where the BASELINK_FUNCTIONS is a
1788 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
1789 there is no reason to do the lookup twice, so the parser keeps the
1793 finish_class_member_access_expr (tree object, tree name)
1798 tree access_path = NULL_TREE;
1799 tree orig_object = object;
1800 tree orig_name = name;
1802 if (object == error_mark_node || name == error_mark_node)
1803 return error_mark_node;
1805 object_type = TREE_TYPE (object);
1807 if (processing_template_decl)
1809 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
1810 dependent_type_p (object_type)
1811 /* If NAME is "f<args>", where either 'f' or 'args' is
1812 dependent, then the expression is dependent. */
1813 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
1814 && dependent_template_id_p (TREE_OPERAND (name, 0),
1815 TREE_OPERAND (name, 1)))
1816 /* If NAME is "T::X" where "T" is dependent, then the
1817 expression is dependent. */
1818 || (TREE_CODE (name) == SCOPE_REF
1819 && TYPE_P (TREE_OPERAND (name, 0))
1820 && dependent_type_p (TREE_OPERAND (name, 0))))
1821 return build_min_nt (COMPONENT_REF, object, name);
1822 object = build_non_dependent_expr (object);
1825 if (TREE_CODE (object_type) == REFERENCE_TYPE)
1827 object = convert_from_reference (object);
1828 object_type = TREE_TYPE (object);
1833 The type of the first expression shall be "class object" (of a
1835 if (!complete_type_or_else (object_type, object))
1836 return error_mark_node;
1837 if (!CLASS_TYPE_P (object_type))
1839 error ("request for member `%D' in `%E', which is of non-class type `%T'",
1840 name, object, object_type);
1841 return error_mark_node;
1844 if (BASELINK_P (name))
1846 /* A member function that has already been looked up. */
1847 my_friendly_assert ((TREE_CODE (BASELINK_FUNCTIONS (name))
1848 == TEMPLATE_ID_EXPR),
1854 bool is_template_id = false;
1855 tree template_args = NULL_TREE;
1858 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
1860 is_template_id = true;
1861 template_args = TREE_OPERAND (name, 1);
1862 name = TREE_OPERAND (name, 0);
1865 if (TREE_CODE (name) == SCOPE_REF)
1867 /* A qualified name. The qualifying class or namespace `S' has
1868 already been looked up; it is either a TYPE or a
1869 NAMESPACE_DECL. The member name is either an IDENTIFIER_NODE
1870 or a BIT_NOT_EXPR. */
1871 scope = TREE_OPERAND (name, 0);
1872 name = TREE_OPERAND (name, 1);
1873 my_friendly_assert ((CLASS_TYPE_P (scope)
1874 || TREE_CODE (scope) == NAMESPACE_DECL),
1876 my_friendly_assert ((TREE_CODE (name) == IDENTIFIER_NODE
1877 || TREE_CODE (name) == BIT_NOT_EXPR),
1880 /* If SCOPE is a namespace, then the qualified name does not
1881 name a member of OBJECT_TYPE. */
1882 if (TREE_CODE (scope) == NAMESPACE_DECL)
1884 error ("`%D::%D' is not a member of `%T'",
1885 scope, name, object_type);
1886 return error_mark_node;
1889 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
1890 access_path = lookup_base (object_type, scope, ba_check, NULL);
1891 if (!access_path || access_path == error_mark_node)
1892 return error_mark_node;
1897 access_path = object_type;
1900 if (TREE_CODE (name) == BIT_NOT_EXPR)
1901 member = lookup_destructor (object, scope, name);
1904 /* Look up the member. */
1905 member = lookup_member (access_path, name, /*protect=*/1,
1906 /*want_type=*/false);
1907 if (member == NULL_TREE)
1909 error ("'%D' has no member named '%E'", object_type, name);
1910 return error_mark_node;
1912 if (member == error_mark_node)
1913 return error_mark_node;
1918 tree template = member;
1920 if (BASELINK_P (template))
1921 template = lookup_template_function (template, template_args);
1924 error ("`%D' is not a member template function", name);
1925 return error_mark_node;
1930 if (TREE_DEPRECATED (member))
1931 warn_deprecated_use (member);
1933 expr = build_class_member_access_expr (object, member, access_path,
1934 /*preserve_reference=*/false);
1935 if (processing_template_decl && expr != error_mark_node)
1936 return build_min_non_dep (COMPONENT_REF, expr,
1937 orig_object, orig_name);
1941 /* Return an expression for the MEMBER_NAME field in the internal
1942 representation of PTRMEM, a pointer-to-member function. (Each
1943 pointer-to-member function type gets its own RECORD_TYPE so it is
1944 more convenient to access the fields by name than by FIELD_DECL.)
1945 This routine converts the NAME to a FIELD_DECL and then creates the
1946 node for the complete expression. */
1949 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
1955 /* This code is a stripped down version of
1956 build_class_member_access_expr. It does not work to use that
1957 routine directly because it expects the object to be of class
1959 ptrmem_type = TREE_TYPE (ptrmem);
1960 my_friendly_assert (TYPE_PTRMEMFUNC_P (ptrmem_type), 20020804);
1961 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
1962 /*want_type=*/false);
1963 member_type = cp_build_qualified_type (TREE_TYPE (member),
1964 cp_type_quals (ptrmem_type));
1965 return fold (build (COMPONENT_REF, member_type, ptrmem, member));
1968 /* Given an expression PTR for a pointer, return an expression
1969 for the value pointed to.
1970 ERRORSTRING is the name of the operator to appear in error messages.
1972 This function may need to overload OPERATOR_FNNAME.
1973 Must also handle REFERENCE_TYPEs for C++. */
1976 build_x_indirect_ref (tree expr, const char *errorstring)
1978 tree orig_expr = expr;
1981 if (processing_template_decl)
1983 if (type_dependent_expression_p (expr))
1984 return build_min_nt (INDIRECT_REF, expr);
1985 expr = build_non_dependent_expr (expr);
1988 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
1991 rval = build_indirect_ref (expr, errorstring);
1993 if (processing_template_decl && rval != error_mark_node)
1994 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2000 build_indirect_ref (tree ptr, const char *errorstring)
2002 register tree pointer, type;
2004 if (ptr == error_mark_node)
2005 return error_mark_node;
2007 if (ptr == current_class_ptr)
2008 return current_class_ref;
2010 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2011 ? ptr : decay_conversion (ptr));
2012 type = TREE_TYPE (pointer);
2014 if (TYPE_PTR_P (type) || TREE_CODE (type) == REFERENCE_TYPE)
2018 If the type of the expression is "pointer to T," the type
2019 of the result is "T."
2021 We must use the canonical variant because certain parts of
2022 the back end, like fold, do pointer comparisons between
2024 tree t = canonical_type_variant (TREE_TYPE (type));
2026 if (VOID_TYPE_P (t))
2028 /* A pointer to incomplete type (other than cv void) can be
2029 dereferenced [expr.unary.op]/1 */
2030 error ("`%T' is not a pointer-to-object type", type);
2031 return error_mark_node;
2033 else if (TREE_CODE (pointer) == ADDR_EXPR
2034 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2035 /* The POINTER was something like `&x'. We simplify `*&x' to
2037 return TREE_OPERAND (pointer, 0);
2040 tree ref = build1 (INDIRECT_REF, t, pointer);
2042 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2043 so that we get the proper error message if the result is used
2044 to assign to. Also, &* is supposed to be a no-op. */
2045 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2046 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2047 TREE_SIDE_EFFECTS (ref)
2048 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2052 /* `pointer' won't be an error_mark_node if we were given a
2053 pointer to member, so it's cool to check for this here. */
2054 else if (TYPE_PTR_TO_MEMBER_P (type))
2055 error ("invalid use of `%s' on pointer to member", errorstring);
2056 else if (pointer != error_mark_node)
2059 error ("invalid type argument of `%s'", errorstring);
2061 error ("invalid type argument");
2063 return error_mark_node;
2066 /* This handles expressions of the form "a[i]", which denotes
2069 This is logically equivalent in C to *(a+i), but we may do it differently.
2070 If A is a variable or a member, we generate a primitive ARRAY_REF.
2071 This avoids forcing the array out of registers, and can work on
2072 arrays that are not lvalues (for example, members of structures returned
2075 If INDEX is of some user-defined type, it must be converted to
2076 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2077 will inherit the type of the array, which will be some pointer type. */
2080 build_array_ref (tree array, tree idx)
2084 error ("subscript missing in array reference");
2085 return error_mark_node;
2088 if (TREE_TYPE (array) == error_mark_node
2089 || TREE_TYPE (idx) == error_mark_node)
2090 return error_mark_node;
2092 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2094 switch (TREE_CODE (array))
2098 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2099 return build (COMPOUND_EXPR, TREE_TYPE (value),
2100 TREE_OPERAND (array, 0), value);
2104 return build_conditional_expr
2105 (TREE_OPERAND (array, 0),
2106 build_array_ref (TREE_OPERAND (array, 1), idx),
2107 build_array_ref (TREE_OPERAND (array, 2), idx));
2113 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
2114 && TREE_CODE (array) != INDIRECT_REF)
2118 /* Subscripting with type char is likely to lose
2119 on a machine where chars are signed.
2120 So warn on any machine, but optionally.
2121 Don't warn for unsigned char since that type is safe.
2122 Don't warn for signed char because anyone who uses that
2123 must have done so deliberately. */
2124 if (warn_char_subscripts
2125 && TYPE_MAIN_VARIANT (TREE_TYPE (idx)) == char_type_node)
2126 warning ("array subscript has type `char'");
2128 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2130 error ("array subscript is not an integer");
2131 return error_mark_node;
2134 /* Apply integral promotions *after* noticing character types.
2135 (It is unclear why we do these promotions -- the standard
2136 does not say that we should. In fact, the natual thing would
2137 seem to be to convert IDX to ptrdiff_t; we're performing
2138 pointer arithmetic.) */
2139 idx = perform_integral_promotions (idx);
2141 /* An array that is indexed by a non-constant
2142 cannot be stored in a register; we must be able to do
2143 address arithmetic on its address.
2144 Likewise an array of elements of variable size. */
2145 if (TREE_CODE (idx) != INTEGER_CST
2146 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2147 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2150 if (!cxx_mark_addressable (array))
2151 return error_mark_node;
2154 /* An array that is indexed by a constant value which is not within
2155 the array bounds cannot be stored in a register either; because we
2156 would get a crash in store_bit_field/extract_bit_field when trying
2157 to access a non-existent part of the register. */
2158 if (TREE_CODE (idx) == INTEGER_CST
2159 && TYPE_VALUES (TREE_TYPE (array))
2160 && ! int_fits_type_p (idx, TYPE_VALUES (TREE_TYPE (array))))
2162 if (!cxx_mark_addressable (array))
2163 return error_mark_node;
2166 if (pedantic && !lvalue_p (array))
2167 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2169 /* Note in C++ it is valid to subscript a `register' array, since
2170 it is valid to take the address of something with that
2171 storage specification. */
2175 while (TREE_CODE (foo) == COMPONENT_REF)
2176 foo = TREE_OPERAND (foo, 0);
2177 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2178 warning ("subscripting array declared `register'");
2181 type = TREE_TYPE (TREE_TYPE (array));
2182 rval = build (ARRAY_REF, type, array, idx);
2183 /* Array ref is const/volatile if the array elements are
2184 or if the array is.. */
2185 TREE_READONLY (rval)
2186 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2187 TREE_SIDE_EFFECTS (rval)
2188 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2189 TREE_THIS_VOLATILE (rval)
2190 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2191 return require_complete_type (fold (rval));
2195 tree ar = default_conversion (array);
2196 tree ind = default_conversion (idx);
2198 /* Put the integer in IND to simplify error checking. */
2199 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2206 if (ar == error_mark_node)
2209 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2211 error ("subscripted value is neither array nor pointer");
2212 return error_mark_node;
2214 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2216 error ("array subscript is not an integer");
2217 return error_mark_node;
2220 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2225 /* Resolve a pointer to member function. INSTANCE is the object
2226 instance to use, if the member points to a virtual member.
2228 This used to avoid checking for virtual functions if basetype
2229 has no virtual functions, according to an earlier ANSI draft.
2230 With the final ISO C++ rules, such an optimization is
2231 incorrect: A pointer to a derived member can be static_cast
2232 to pointer-to-base-member, as long as the dynamic object
2233 later has the right member. */
2236 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2238 if (TREE_CODE (function) == OFFSET_REF)
2239 function = TREE_OPERAND (function, 1);
2241 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2243 tree idx, delta, e1, e2, e3, vtbl, basetype;
2244 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2246 tree instance_ptr = *instance_ptrptr;
2247 tree instance_save_expr = 0;
2248 if (instance_ptr == error_mark_node)
2250 if (TREE_CODE (function) == PTRMEM_CST)
2252 /* Extracting the function address from a pmf is only
2253 allowed with -Wno-pmf-conversions. It only works for
2255 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2256 e1 = convert (fntype, e1);
2261 error ("object missing in use of `%E'", function);
2262 return error_mark_node;
2266 if (TREE_SIDE_EFFECTS (instance_ptr))
2267 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2269 if (TREE_SIDE_EFFECTS (function))
2270 function = save_expr (function);
2272 /* Start by extracting all the information from the PMF itself. */
2273 e3 = PFN_FROM_PTRMEMFUNC (function);
2274 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2275 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2276 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2278 case ptrmemfunc_vbit_in_pfn:
2279 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2280 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2283 case ptrmemfunc_vbit_in_delta:
2284 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2285 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2292 /* Convert down to the right base before using the instance. First
2294 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2295 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2296 basetype, ba_check, NULL);
2297 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype, 1);
2298 if (instance_ptr == error_mark_node)
2299 return error_mark_node;
2300 /* ...and then the delta in the PMF. */
2301 instance_ptr = build (PLUS_EXPR, TREE_TYPE (instance_ptr),
2302 instance_ptr, delta);
2304 /* Hand back the adjusted 'this' argument to our caller. */
2305 *instance_ptrptr = instance_ptr;
2307 /* Next extract the vtable pointer from the object. */
2308 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2310 vtbl = build_indirect_ref (vtbl, NULL);
2312 /* Finally, extract the function pointer from the vtable. */
2313 e2 = fold (build (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx));
2314 e2 = build_indirect_ref (e2, NULL);
2315 TREE_CONSTANT (e2) = 1;
2317 /* When using function descriptors, the address of the
2318 vtable entry is treated as a function pointer. */
2319 if (TARGET_VTABLE_USES_DESCRIPTORS)
2320 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2321 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2323 TREE_TYPE (e2) = TREE_TYPE (e3);
2324 e1 = build_conditional_expr (e1, e2, e3);
2326 /* Make sure this doesn't get evaluated first inside one of the
2327 branches of the COND_EXPR. */
2328 if (instance_save_expr)
2329 e1 = build (COMPOUND_EXPR, TREE_TYPE (e1),
2330 instance_save_expr, e1);
2338 build_function_call (tree function, tree params)
2340 register tree fntype, fndecl;
2341 register tree coerced_params;
2343 tree name = NULL_TREE, assembler_name = NULL_TREE;
2345 tree original = function;
2347 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2348 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2349 if (TREE_CODE (function) == NOP_EXPR
2350 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2351 function = TREE_OPERAND (function, 0);
2353 if (TREE_CODE (function) == FUNCTION_DECL)
2355 name = DECL_NAME (function);
2356 assembler_name = DECL_ASSEMBLER_NAME (function);
2358 mark_used (function);
2361 /* Convert anything with function type to a pointer-to-function. */
2362 if (pedantic && DECL_MAIN_P (function))
2363 pedwarn ("ISO C++ forbids calling `::main' from within program");
2365 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2366 (because calling an inline function does not mean the function
2367 needs to be separately compiled). */
2369 if (DECL_INLINE (function))
2370 function = inline_conversion (function);
2372 function = build_addr_func (function);
2378 function = build_addr_func (function);
2381 if (function == error_mark_node)
2382 return error_mark_node;
2384 fntype = TREE_TYPE (function);
2386 if (TYPE_PTRMEMFUNC_P (fntype))
2388 error ("must use .* or ->* to call pointer-to-member function in `%E (...)'",
2390 return error_mark_node;
2393 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2394 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2396 if (!((TREE_CODE (fntype) == POINTER_TYPE
2397 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2399 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2401 error ("`%E' cannot be used as a function", original);
2402 return error_mark_node;
2405 /* fntype now gets the type of function pointed to. */
2406 fntype = TREE_TYPE (fntype);
2408 /* Convert the parameters to the types declared in the
2409 function prototype, or apply default promotions. */
2411 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2412 params, fndecl, LOOKUP_NORMAL);
2413 if (coerced_params == error_mark_node)
2414 return error_mark_node;
2416 /* Check for errors in format strings. */
2419 check_function_format (NULL, TYPE_ATTRIBUTES (fntype), coerced_params);
2421 /* Recognize certain built-in functions so we can make tree-codes
2422 other than CALL_EXPR. We do this when it enables fold-const.c
2423 to do something useful. */
2425 if (TREE_CODE (function) == ADDR_EXPR
2426 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
2427 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
2429 result = expand_tree_builtin (TREE_OPERAND (function, 0),
2430 params, coerced_params);
2435 return build_cxx_call (function, params, coerced_params);
2438 /* Convert the actual parameter expressions in the list VALUES
2439 to the types in the list TYPELIST.
2440 If parmdecls is exhausted, or when an element has NULL as its type,
2441 perform the default conversions.
2443 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2445 This is also where warnings about wrong number of args are generated.
2447 Return a list of expressions for the parameters as converted.
2449 Both VALUES and the returned value are chains of TREE_LIST nodes
2450 with the elements of the list in the TREE_VALUE slots of those nodes.
2452 In C++, unspecified trailing parameters can be filled in with their
2453 default arguments, if such were specified. Do so here. */
2456 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2458 register tree typetail, valtail;
2459 register tree result = NULL_TREE;
2460 const char *called_thing = 0;
2463 /* Argument passing is always copy-initialization. */
2464 flags |= LOOKUP_ONLYCONVERTING;
2468 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2470 if (DECL_NAME (fndecl) == NULL_TREE
2471 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2472 called_thing = "constructor";
2474 called_thing = "member function";
2477 called_thing = "function";
2480 for (valtail = values, typetail = typelist;
2482 valtail = TREE_CHAIN (valtail), i++)
2484 register tree type = typetail ? TREE_VALUE (typetail) : 0;
2485 register tree val = TREE_VALUE (valtail);
2487 if (val == error_mark_node)
2488 return error_mark_node;
2490 if (type == void_type_node)
2494 cp_error_at ("too many arguments to %s `%+#D'", called_thing,
2496 error ("at this point in file");
2499 error ("too many arguments to function");
2500 /* In case anybody wants to know if this argument
2503 TREE_TYPE (tree_last (result)) = error_mark_node;
2507 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2508 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2509 if (TREE_CODE (val) == NOP_EXPR
2510 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2511 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2512 val = TREE_OPERAND (val, 0);
2514 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2516 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2517 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2518 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2519 val = decay_conversion (val);
2522 if (val == error_mark_node)
2523 return error_mark_node;
2527 /* Formal parm type is specified by a function prototype. */
2530 if (!COMPLETE_TYPE_P (complete_type (type)))
2533 error ("parameter %P of `%D' has incomplete type `%T'",
2536 error ("parameter %P has incomplete type `%T'", i, type);
2537 parmval = error_mark_node;
2541 parmval = convert_for_initialization
2542 (NULL_TREE, type, val, flags,
2543 "argument passing", fndecl, i);
2544 parmval = convert_for_arg_passing (type, parmval);
2547 if (parmval == error_mark_node)
2548 return error_mark_node;
2550 result = tree_cons (NULL_TREE, parmval, result);
2554 if (TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE)
2555 val = convert_from_reference (val);
2557 if (fndecl && DECL_BUILT_IN (fndecl)
2558 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2559 /* Don't do ellipsis conversion for __built_in_constant_p
2560 as this will result in spurious warnings for non-POD
2562 val = require_complete_type (val);
2564 val = convert_arg_to_ellipsis (val);
2566 result = tree_cons (NULL_TREE, val, result);
2570 typetail = TREE_CHAIN (typetail);
2573 if (typetail != 0 && typetail != void_list_node)
2575 /* See if there are default arguments that can be used */
2576 if (TREE_PURPOSE (typetail)
2577 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2579 for (; typetail != void_list_node; ++i)
2582 = convert_default_arg (TREE_VALUE (typetail),
2583 TREE_PURPOSE (typetail),
2586 if (parmval == error_mark_node)
2587 return error_mark_node;
2589 result = tree_cons (0, parmval, result);
2590 typetail = TREE_CHAIN (typetail);
2591 /* ends with `...'. */
2592 if (typetail == NULL_TREE)
2600 cp_error_at ("too few arguments to %s `%+#D'",
2601 called_thing, fndecl);
2602 error ("at this point in file");
2605 error ("too few arguments to function");
2606 return error_mark_list;
2610 return nreverse (result);
2613 /* Build a binary-operation expression, after performing default
2614 conversions on the operands. CODE is the kind of expression to build. */
2617 build_x_binary_op (enum tree_code code, tree arg1, tree arg2)
2626 if (processing_template_decl)
2628 if (type_dependent_expression_p (arg1)
2629 || type_dependent_expression_p (arg2))
2630 return build_min_nt (code, arg1, arg2);
2631 arg1 = build_non_dependent_expr (arg1);
2632 arg2 = build_non_dependent_expr (arg2);
2635 if (code == DOTSTAR_EXPR)
2636 expr = build_m_component_ref (arg1, arg2);
2638 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE);
2640 if (processing_template_decl && expr != error_mark_node)
2641 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2646 /* Build a binary-operation expression without default conversions.
2647 CODE is the kind of expression to build.
2648 This function differs from `build' in several ways:
2649 the data type of the result is computed and recorded in it,
2650 warnings are generated if arg data types are invalid,
2651 special handling for addition and subtraction of pointers is known,
2652 and some optimization is done (operations on narrow ints
2653 are done in the narrower type when that gives the same result).
2654 Constant folding is also done before the result is returned.
2656 Note that the operands will never have enumeral types
2657 because either they have just had the default conversions performed
2658 or they have both just been converted to some other type in which
2659 the arithmetic is to be done.
2661 C++: must do special pointer arithmetic when implementing
2662 multiple inheritance, and deal with pointer to member functions. */
2665 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2666 int convert_p ATTRIBUTE_UNUSED)
2669 register enum tree_code code0, code1;
2672 /* Expression code to give to the expression when it is built.
2673 Normally this is CODE, which is what the caller asked for,
2674 but in some special cases we change it. */
2675 register enum tree_code resultcode = code;
2677 /* Data type in which the computation is to be performed.
2678 In the simplest cases this is the common type of the arguments. */
2679 register tree result_type = NULL;
2681 /* Nonzero means operands have already been type-converted
2682 in whatever way is necessary.
2683 Zero means they need to be converted to RESULT_TYPE. */
2686 /* Nonzero means create the expression with this type, rather than
2688 tree build_type = 0;
2690 /* Nonzero means after finally constructing the expression
2691 convert it to this type. */
2692 tree final_type = 0;
2694 /* Nonzero if this is an operation like MIN or MAX which can
2695 safely be computed in short if both args are promoted shorts.
2696 Also implies COMMON.
2697 -1 indicates a bitwise operation; this makes a difference
2698 in the exact conditions for when it is safe to do the operation
2699 in a narrower mode. */
2702 /* Nonzero if this is a comparison operation;
2703 if both args are promoted shorts, compare the original shorts.
2704 Also implies COMMON. */
2705 int short_compare = 0;
2707 /* Nonzero if this is a right-shift operation, which can be computed on the
2708 original short and then promoted if the operand is a promoted short. */
2709 int short_shift = 0;
2711 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2714 /* Apply default conversions. */
2718 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2719 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2720 || code == TRUTH_XOR_EXPR)
2722 if (!really_overloaded_fn (op0))
2723 op0 = decay_conversion (op0);
2724 if (!really_overloaded_fn (op1))
2725 op1 = decay_conversion (op1);
2729 if (!really_overloaded_fn (op0))
2730 op0 = default_conversion (op0);
2731 if (!really_overloaded_fn (op1))
2732 op1 = default_conversion (op1);
2735 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2736 STRIP_TYPE_NOPS (op0);
2737 STRIP_TYPE_NOPS (op1);
2739 /* DTRT if one side is an overloaded function, but complain about it. */
2740 if (type_unknown_p (op0))
2742 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
2743 if (t != error_mark_node)
2745 pedwarn ("assuming cast to type `%T' from overloaded function",
2750 if (type_unknown_p (op1))
2752 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
2753 if (t != error_mark_node)
2755 pedwarn ("assuming cast to type `%T' from overloaded function",
2761 type0 = TREE_TYPE (op0);
2762 type1 = TREE_TYPE (op1);
2764 /* The expression codes of the data types of the arguments tell us
2765 whether the arguments are integers, floating, pointers, etc. */
2766 code0 = TREE_CODE (type0);
2767 code1 = TREE_CODE (type1);
2769 /* If an error was already reported for one of the arguments,
2770 avoid reporting another error. */
2772 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
2773 return error_mark_node;
2778 /* Handle the pointer + int case. */
2779 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2780 return cp_pointer_int_sum (PLUS_EXPR, op0, op1);
2781 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
2782 return cp_pointer_int_sum (PLUS_EXPR, op1, op0);
2788 /* Subtraction of two similar pointers.
2789 We must subtract them as integers, then divide by object size. */
2790 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
2791 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
2793 return pointer_diff (op0, op1, common_type (type0, type1));
2794 /* Handle pointer minus int. Just like pointer plus int. */
2795 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2796 return cp_pointer_int_sum (MINUS_EXPR, op0, op1);
2805 case TRUNC_DIV_EXPR:
2807 case FLOOR_DIV_EXPR:
2808 case ROUND_DIV_EXPR:
2809 case EXACT_DIV_EXPR:
2810 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2811 || code0 == COMPLEX_TYPE)
2812 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2813 || code1 == COMPLEX_TYPE))
2815 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
2816 warning ("division by zero in `%E / 0'", op0);
2817 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
2818 warning ("division by zero in `%E / 0.'", op0);
2820 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
2821 resultcode = RDIV_EXPR;
2823 /* When dividing two signed integers, we have to promote to int.
2824 unless we divide by a constant != -1. Note that default
2825 conversion will have been performed on the operands at this
2826 point, so we have to dig out the original type to find out if
2828 shorten = ((TREE_CODE (op0) == NOP_EXPR
2829 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2830 || (TREE_CODE (op1) == INTEGER_CST
2831 && ! integer_all_onesp (op1)));
2840 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2844 case TRUNC_MOD_EXPR:
2845 case FLOOR_MOD_EXPR:
2846 if (code1 == INTEGER_TYPE && integer_zerop (op1))
2847 warning ("division by zero in `%E %% 0'", op0);
2848 else if (code1 == REAL_TYPE && real_zerop (op1))
2849 warning ("division by zero in `%E %% 0.'", op0);
2851 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2853 /* Although it would be tempting to shorten always here, that loses
2854 on some targets, since the modulo instruction is undefined if the
2855 quotient can't be represented in the computation mode. We shorten
2856 only if unsigned or if dividing by something we know != -1. */
2857 shorten = ((TREE_CODE (op0) == NOP_EXPR
2858 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2859 || (TREE_CODE (op1) == INTEGER_CST
2860 && ! integer_all_onesp (op1)));
2865 case TRUTH_ANDIF_EXPR:
2866 case TRUTH_ORIF_EXPR:
2867 case TRUTH_AND_EXPR:
2869 result_type = boolean_type_node;
2872 /* Shift operations: result has same type as first operand;
2873 always convert second operand to int.
2874 Also set SHORT_SHIFT if shifting rightward. */
2877 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2879 result_type = type0;
2880 if (TREE_CODE (op1) == INTEGER_CST)
2882 if (tree_int_cst_lt (op1, integer_zero_node))
2883 warning ("right shift count is negative");
2886 if (! integer_zerop (op1))
2888 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2889 warning ("right shift count >= width of type");
2892 /* Convert the shift-count to an integer, regardless of
2893 size of value being shifted. */
2894 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2895 op1 = cp_convert (integer_type_node, op1);
2896 /* Avoid converting op1 to result_type later. */
2902 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2904 result_type = type0;
2905 if (TREE_CODE (op1) == INTEGER_CST)
2907 if (tree_int_cst_lt (op1, integer_zero_node))
2908 warning ("left shift count is negative");
2909 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2910 warning ("left shift count >= width of type");
2912 /* Convert the shift-count to an integer, regardless of
2913 size of value being shifted. */
2914 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2915 op1 = cp_convert (integer_type_node, op1);
2916 /* Avoid converting op1 to result_type later. */
2923 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2925 result_type = type0;
2926 if (TREE_CODE (op1) == INTEGER_CST)
2928 if (tree_int_cst_lt (op1, integer_zero_node))
2929 warning ("%s rotate count is negative",
2930 (code == LROTATE_EXPR) ? "left" : "right");
2931 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2932 warning ("%s rotate count >= width of type",
2933 (code == LROTATE_EXPR) ? "left" : "right");
2935 /* Convert the shift-count to an integer, regardless of
2936 size of value being shifted. */
2937 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2938 op1 = cp_convert (integer_type_node, op1);
2944 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
2945 warning ("comparing floating point with == or != is unsafe");
2947 build_type = boolean_type_node;
2948 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2949 || code0 == COMPLEX_TYPE)
2950 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2951 || code1 == COMPLEX_TYPE))
2953 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2954 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
2955 result_type = composite_pointer_type (type0, type1, op0, op1,
2957 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
2958 && null_ptr_cst_p (op1))
2959 result_type = type0;
2960 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
2961 && null_ptr_cst_p (op0))
2962 result_type = type1;
2963 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2965 result_type = type0;
2966 error ("ISO C++ forbids comparison between pointer and integer");
2968 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2970 result_type = type1;
2971 error ("ISO C++ forbids comparison between pointer and integer");
2973 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
2975 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
2976 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
2977 result_type = TREE_TYPE (op0);
2979 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
2980 return cp_build_binary_op (code, op1, op0);
2981 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
2982 && same_type_p (type0, type1))
2984 /* E will be the final comparison. */
2986 /* E1 and E2 are for scratch. */
2994 if (TREE_SIDE_EFFECTS (op0))
2995 op0 = save_expr (op0);
2996 if (TREE_SIDE_EFFECTS (op1))
2997 op1 = save_expr (op1);
3002 && (!op0.pfn || op0.delta == op1.delta))
3004 The reason for the `!op0.pfn' bit is that a NULL
3005 pointer-to-member is any member with a zero PFN; the
3006 DELTA field is unspecified. */
3007 pfn0 = pfn_from_ptrmemfunc (op0);
3008 pfn1 = pfn_from_ptrmemfunc (op1);
3009 delta0 = build_ptrmemfunc_access_expr (op0,
3011 delta1 = build_ptrmemfunc_access_expr (op1,
3013 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3014 e2 = cp_build_binary_op (EQ_EXPR,
3016 cp_convert (TREE_TYPE (pfn0),
3017 integer_zero_node));
3018 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3019 e2 = build (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3020 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3021 if (code == EQ_EXPR)
3023 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3025 else if ((TYPE_PTRMEMFUNC_P (type0)
3026 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0), type1))
3027 || (TYPE_PTRMEMFUNC_P (type1)
3028 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1), type0)))
3034 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3035 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3037 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3038 result_type = composite_pointer_type (type0, type1, op0, op1,
3046 build_type = boolean_type_node;
3047 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3048 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3050 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3051 result_type = composite_pointer_type (type0, type1, op0, op1,
3053 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3054 && integer_zerop (op1))
3055 result_type = type0;
3056 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3057 && integer_zerop (op0))
3058 result_type = type1;
3059 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3061 result_type = type0;
3062 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3064 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3066 result_type = type1;
3067 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3071 case UNORDERED_EXPR:
3078 build_type = integer_type_node;
3079 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3081 error ("unordered comparison on non-floating point argument");
3082 return error_mark_node;
3091 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3093 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
3095 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3097 if (shorten || common || short_compare)
3098 result_type = common_type (type0, type1);
3100 /* For certain operations (which identify themselves by shorten != 0)
3101 if both args were extended from the same smaller type,
3102 do the arithmetic in that type and then extend.
3104 shorten !=0 and !=1 indicates a bitwise operation.
3105 For them, this optimization is safe only if
3106 both args are zero-extended or both are sign-extended.
3107 Otherwise, we might change the result.
3108 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3109 but calculated in (unsigned short) it would be (unsigned short)-1. */
3111 if (shorten && none_complex)
3113 int unsigned0, unsigned1;
3114 tree arg0 = get_narrower (op0, &unsigned0);
3115 tree arg1 = get_narrower (op1, &unsigned1);
3116 /* UNS is 1 if the operation to be done is an unsigned one. */
3117 int uns = TREE_UNSIGNED (result_type);
3120 final_type = result_type;
3122 /* Handle the case that OP0 does not *contain* a conversion
3123 but it *requires* conversion to FINAL_TYPE. */
3125 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3126 unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
3127 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3128 unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
3130 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3132 /* For bitwise operations, signedness of nominal type
3133 does not matter. Consider only how operands were extended. */
3137 /* Note that in all three cases below we refrain from optimizing
3138 an unsigned operation on sign-extended args.
3139 That would not be valid. */
3141 /* Both args variable: if both extended in same way
3142 from same width, do it in that width.
3143 Do it unsigned if args were zero-extended. */
3144 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3145 < TYPE_PRECISION (result_type))
3146 && (TYPE_PRECISION (TREE_TYPE (arg1))
3147 == TYPE_PRECISION (TREE_TYPE (arg0)))
3148 && unsigned0 == unsigned1
3149 && (unsigned0 || !uns))
3150 result_type = c_common_signed_or_unsigned_type
3151 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3152 else if (TREE_CODE (arg0) == INTEGER_CST
3153 && (unsigned1 || !uns)
3154 && (TYPE_PRECISION (TREE_TYPE (arg1))
3155 < TYPE_PRECISION (result_type))
3156 && (type = c_common_signed_or_unsigned_type
3157 (unsigned1, TREE_TYPE (arg1)),
3158 int_fits_type_p (arg0, type)))
3160 else if (TREE_CODE (arg1) == INTEGER_CST
3161 && (unsigned0 || !uns)
3162 && (TYPE_PRECISION (TREE_TYPE (arg0))
3163 < TYPE_PRECISION (result_type))
3164 && (type = c_common_signed_or_unsigned_type
3165 (unsigned0, TREE_TYPE (arg0)),
3166 int_fits_type_p (arg1, type)))
3170 /* Shifts can be shortened if shifting right. */
3175 tree arg0 = get_narrower (op0, &unsigned_arg);
3177 final_type = result_type;
3179 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3180 unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
3182 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3183 /* We can shorten only if the shift count is less than the
3184 number of bits in the smaller type size. */
3185 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3186 /* If arg is sign-extended and then unsigned-shifted,
3187 we can simulate this with a signed shift in arg's type
3188 only if the extended result is at least twice as wide
3189 as the arg. Otherwise, the shift could use up all the
3190 ones made by sign-extension and bring in zeros.
3191 We can't optimize that case at all, but in most machines
3192 it never happens because available widths are 2**N. */
3193 && (!TREE_UNSIGNED (final_type)
3195 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3196 <= TYPE_PRECISION (result_type))))
3198 /* Do an unsigned shift if the operand was zero-extended. */
3200 = c_common_signed_or_unsigned_type (unsigned_arg,
3202 /* Convert value-to-be-shifted to that type. */
3203 if (TREE_TYPE (op0) != result_type)
3204 op0 = cp_convert (result_type, op0);
3209 /* Comparison operations are shortened too but differently.
3210 They identify themselves by setting short_compare = 1. */
3214 /* Don't write &op0, etc., because that would prevent op0
3215 from being kept in a register.
3216 Instead, make copies of the our local variables and
3217 pass the copies by reference, then copy them back afterward. */
3218 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3219 enum tree_code xresultcode = resultcode;
3221 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3223 return cp_convert (boolean_type_node, val);
3224 op0 = xop0, op1 = xop1;
3226 resultcode = xresultcode;
3229 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3230 && warn_sign_compare
3231 /* Do not warn until the template is instantiated; we cannot
3232 bound the ranges of the arguments until that point. */
3233 && !processing_template_decl)
3235 int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0));
3236 int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1));
3238 int unsignedp0, unsignedp1;
3239 tree primop0 = get_narrower (op0, &unsignedp0);
3240 tree primop1 = get_narrower (op1, &unsignedp1);
3242 /* Check for comparison of different enum types. */
3243 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3244 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3245 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3246 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3248 warning ("comparison between types `%#T' and `%#T'",
3249 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3252 /* Give warnings for comparisons between signed and unsigned
3253 quantities that may fail. */
3254 /* Do the checking based on the original operand trees, so that
3255 casts will be considered, but default promotions won't be. */
3257 /* Do not warn if the comparison is being done in a signed type,
3258 since the signed type will only be chosen if it can represent
3259 all the values of the unsigned type. */
3260 if (! TREE_UNSIGNED (result_type))
3262 /* Do not warn if both operands are unsigned. */
3263 else if (op0_signed == op1_signed)
3265 /* Do not warn if the signed quantity is an unsuffixed
3266 integer literal (or some static constant expression
3267 involving such literals or a conditional expression
3268 involving such literals) and it is non-negative. */
3269 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3270 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3272 /* Do not warn if the comparison is an equality operation,
3273 the unsigned quantity is an integral constant and it does
3274 not use the most significant bit of result_type. */
3275 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3276 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3277 && int_fits_type_p (orig_op1, c_common_signed_type
3279 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3280 && int_fits_type_p (orig_op0, c_common_signed_type
3284 warning ("comparison between signed and unsigned integer expressions");
3286 /* Warn if two unsigned values are being compared in a size
3287 larger than their original size, and one (and only one) is the
3288 result of a `~' operator. This comparison will always fail.
3290 Also warn if one operand is a constant, and the constant does not
3291 have all bits set that are set in the ~ operand when it is
3294 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3295 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3297 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3298 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3299 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3300 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3302 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3305 HOST_WIDE_INT constant, mask;
3309 if (host_integerp (primop0, 0))
3312 unsignedp = unsignedp1;
3313 constant = tree_low_cst (primop0, 0);
3318 unsignedp = unsignedp0;
3319 constant = tree_low_cst (primop1, 0);
3322 bits = TYPE_PRECISION (TREE_TYPE (primop));
3323 if (bits < TYPE_PRECISION (result_type)
3324 && bits < HOST_BITS_PER_LONG && unsignedp)
3326 mask = (~ (HOST_WIDE_INT) 0) << bits;
3327 if ((mask & constant) != mask)
3328 warning ("comparison of promoted ~unsigned with constant");
3331 else if (unsignedp0 && unsignedp1
3332 && (TYPE_PRECISION (TREE_TYPE (primop0))
3333 < TYPE_PRECISION (result_type))
3334 && (TYPE_PRECISION (TREE_TYPE (primop1))
3335 < TYPE_PRECISION (result_type)))
3336 warning ("comparison of promoted ~unsigned with unsigned");
3341 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
3342 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3343 Then the expression will be built.
3344 It will be given type FINAL_TYPE if that is nonzero;
3345 otherwise, it will be given type RESULT_TYPE. */
3349 error ("invalid operands of types `%T' and `%T' to binary `%O'",
3350 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3351 return error_mark_node;
3354 /* Issue warnings about peculiar, but valid, uses of NULL. */
3355 if (/* It's reasonable to use pointer values as operands of &&
3356 and ||, so NULL is no exception. */
3357 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3358 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3359 (orig_op0 == null_node
3360 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3361 /* Or vice versa. */
3362 || (orig_op1 == null_node
3363 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3364 /* Or, both are NULL and the operation was not a comparison. */
3365 || (orig_op0 == null_node && orig_op1 == null_node
3366 && code != EQ_EXPR && code != NE_EXPR)))
3367 /* Some sort of arithmetic operation involving NULL was
3368 performed. Note that pointer-difference and pointer-addition
3369 have already been handled above, and so we don't end up here in
3371 warning ("NULL used in arithmetic");
3375 if (TREE_TYPE (op0) != result_type)
3376 op0 = cp_convert (result_type, op0);
3377 if (TREE_TYPE (op1) != result_type)
3378 op1 = cp_convert (result_type, op1);
3380 if (op0 == error_mark_node || op1 == error_mark_node)
3381 return error_mark_node;
3384 if (build_type == NULL_TREE)
3385 build_type = result_type;
3388 register tree result = build (resultcode, build_type, op0, op1);
3389 register tree folded;
3391 folded = fold (result);
3392 if (folded == result)
3393 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
3394 if (final_type != 0)
3395 return cp_convert (final_type, folded);
3400 /* Return a tree for the sum or difference (RESULTCODE says which)
3401 of pointer PTROP and integer INTOP. */
3404 cp_pointer_int_sum (enum tree_code resultcode, register tree ptrop,
3405 register tree intop)
3407 tree res_type = TREE_TYPE (ptrop);
3409 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3410 in certain circumstance (when it's valid to do so). So we need
3411 to make sure it's complete. We don't need to check here, if we
3412 can actually complete it at all, as those checks will be done in
3413 pointer_int_sum() anyway. */
3414 complete_type (TREE_TYPE (res_type));
3416 return pointer_int_sum (resultcode, ptrop, fold (intop));
3419 /* Return a tree for the difference of pointers OP0 and OP1.
3420 The resulting tree has type int. */
3423 pointer_diff (register tree op0, register tree op1, register tree ptrtype)
3425 register tree result, folded;
3426 tree restype = ptrdiff_type_node;
3427 tree target_type = TREE_TYPE (ptrtype);
3429 if (!complete_type_or_else (target_type, NULL_TREE))
3430 return error_mark_node;
3432 if (pedantic || warn_pointer_arith)
3434 if (TREE_CODE (target_type) == VOID_TYPE)
3435 pedwarn ("ISO C++ forbids using pointer of type `void *' in subtraction");
3436 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3437 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3438 if (TREE_CODE (target_type) == METHOD_TYPE)
3439 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3442 /* First do the subtraction as integers;
3443 then drop through to build the divide operator. */
3445 op0 = cp_build_binary_op (MINUS_EXPR,
3446 cp_convert (restype, op0),
3447 cp_convert (restype, op1));
3449 /* This generates an error if op1 is a pointer to an incomplete type. */
3450 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3451 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3453 op1 = (TYPE_PTROB_P (ptrtype)
3454 ? size_in_bytes (target_type)
3455 : integer_one_node);
3457 /* Do the division. */
3459 result = build (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3461 folded = fold (result);
3462 if (folded == result)
3463 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
3467 /* Construct and perhaps optimize a tree representation
3468 for a unary operation. CODE, a tree_code, specifies the operation
3469 and XARG is the operand. */
3472 build_x_unary_op (enum tree_code code, tree xarg)
3474 tree orig_expr = xarg;
3478 if (processing_template_decl)
3480 if (type_dependent_expression_p (xarg))
3481 return build_min_nt (code, xarg, NULL_TREE);
3482 xarg = build_non_dependent_expr (xarg);
3487 /* & rec, on incomplete RECORD_TYPEs is the simple opr &, not an
3489 if (code == ADDR_EXPR
3490 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3491 && ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (xarg)))
3492 && !COMPLETE_TYPE_P (TREE_TYPE (xarg)))
3493 || (TREE_CODE (xarg) == OFFSET_REF)))
3494 /* don't look for a function */;
3496 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE);
3497 if (!exp && code == ADDR_EXPR)
3499 /* A pointer to member-function can be formed only by saying
3501 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3502 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3504 if (TREE_CODE (xarg) != OFFSET_REF)
3506 error ("invalid use of '%E' to form a pointer-to-member-function. Use a qualified-id.",
3508 return error_mark_node;
3512 error ("parenthesis around '%E' cannot be used to form a pointer-to-member-function",
3514 PTRMEM_OK_P (xarg) = 1;
3518 if (TREE_CODE (xarg) == OFFSET_REF)
3520 ptrmem = PTRMEM_OK_P (xarg);
3522 if (!ptrmem && !flag_ms_extensions
3523 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3525 /* A single non-static member, make sure we don't allow a
3526 pointer-to-member. */
3527 xarg = build (OFFSET_REF, TREE_TYPE (xarg),
3528 TREE_OPERAND (xarg, 0),
3529 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3530 PTRMEM_OK_P (xarg) = ptrmem;
3533 else if (TREE_CODE (xarg) == TARGET_EXPR)
3534 warning ("taking address of temporary");
3535 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3536 if (TREE_CODE (exp) == ADDR_EXPR)
3537 PTRMEM_OK_P (exp) = ptrmem;
3540 if (processing_template_decl && exp != error_mark_node)
3541 return build_min_non_dep (code, exp, orig_expr,
3542 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3546 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3547 constants, where a null value is represented by an INTEGER_CST of
3551 cp_truthvalue_conversion (tree expr)
3553 tree type = TREE_TYPE (expr);
3554 if (TYPE_PTRMEM_P (type))
3555 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3557 return c_common_truthvalue_conversion (expr);
3560 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3563 condition_conversion (tree expr)
3566 if (processing_template_decl)
3568 t = perform_implicit_conversion (boolean_type_node, expr);
3569 t = fold (build1 (CLEANUP_POINT_EXPR, boolean_type_node, t));
3573 /* Return an ADDR_EXPR giving the address of T. This function
3574 attempts no optimizations or simplifications; it is a low-level
3578 build_address (tree t)
3582 if (error_operand_p (t) || !cxx_mark_addressable (t))
3583 return error_mark_node;
3585 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3587 TREE_CONSTANT (addr) = 1;
3592 /* Return a NOP_EXPR converting EXPR to TYPE. */
3595 build_nop (tree type, tree expr)
3599 if (type == error_mark_node || error_operand_p (expr))
3602 nop = build1 (NOP_EXPR, type, expr);
3603 if (TREE_CONSTANT (expr))
3604 TREE_CONSTANT (nop) = 1;
3609 /* C++: Must handle pointers to members.
3611 Perhaps type instantiation should be extended to handle conversion
3612 from aggregates to types we don't yet know we want? (Or are those
3613 cases typically errors which should be reported?)
3615 NOCONVERT nonzero suppresses the default promotions
3616 (such as from short to int). */
3619 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3621 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3622 register tree arg = xarg;
3623 register tree argtype = 0;
3624 const char *errstring = NULL;
3627 if (arg == error_mark_node)
3628 return error_mark_node;
3633 /* This is used for unary plus, because a CONVERT_EXPR
3634 is enough to prevent anybody from looking inside for
3635 associativity, but won't generate any code. */
3636 if (!(arg = build_expr_type_conversion
3637 (WANT_ARITH | WANT_ENUM | WANT_POINTER, arg, true)))
3638 errstring = "wrong type argument to unary plus";
3642 arg = default_conversion (arg);
3643 arg = build1 (NON_LVALUE_EXPR, TREE_TYPE (arg), arg);
3644 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3649 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3650 errstring = "wrong type argument to unary minus";
3651 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3652 arg = perform_integral_promotions (arg);
3656 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3660 arg = default_conversion (arg);
3662 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
3664 errstring = "wrong type argument to bit-complement";
3665 else if (!noconvert)
3666 arg = perform_integral_promotions (arg);
3670 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3671 errstring = "wrong type argument to abs";
3672 else if (!noconvert)
3673 arg = default_conversion (arg);
3677 /* Conjugating a real value is a no-op, but allow it anyway. */
3678 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3679 errstring = "wrong type argument to conjugation";
3680 else if (!noconvert)
3681 arg = default_conversion (arg);
3684 case TRUTH_NOT_EXPR:
3685 arg = perform_implicit_conversion (boolean_type_node, arg);
3686 val = invert_truthvalue (arg);
3687 if (arg != error_mark_node)
3689 errstring = "in argument to unary !";
3696 if (TREE_CODE (arg) == COMPLEX_CST)
3697 return TREE_REALPART (arg);
3698 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3699 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3704 if (TREE_CODE (arg) == COMPLEX_CST)
3705 return TREE_IMAGPART (arg);
3706 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3707 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3709 return cp_convert (TREE_TYPE (arg), integer_zero_node);
3711 case PREINCREMENT_EXPR:
3712 case POSTINCREMENT_EXPR:
3713 case PREDECREMENT_EXPR:
3714 case POSTDECREMENT_EXPR:
3715 /* Handle complex lvalues (when permitted)
3716 by reduction to simpler cases. */
3718 val = unary_complex_lvalue (code, arg);
3722 /* Increment or decrement the real part of the value,
3723 and don't change the imaginary part. */
3724 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3728 arg = stabilize_reference (arg);
3729 real = build_unary_op (REALPART_EXPR, arg, 1);
3730 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
3731 return build (COMPLEX_EXPR, TREE_TYPE (arg),
3732 build_unary_op (code, real, 1), imag);
3735 /* Report invalid types. */
3737 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
3740 if (code == PREINCREMENT_EXPR)
3741 errstring ="no pre-increment operator for type";
3742 else if (code == POSTINCREMENT_EXPR)
3743 errstring ="no post-increment operator for type";
3744 else if (code == PREDECREMENT_EXPR)
3745 errstring ="no pre-decrement operator for type";
3747 errstring ="no post-decrement operator for type";
3751 /* Report something read-only. */
3753 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
3754 || TREE_READONLY (arg))
3755 readonly_error (arg, ((code == PREINCREMENT_EXPR
3756 || code == POSTINCREMENT_EXPR)
3757 ? "increment" : "decrement"),
3762 tree result_type = TREE_TYPE (arg);
3764 arg = get_unwidened (arg, 0);
3765 argtype = TREE_TYPE (arg);
3767 /* ARM $5.2.5 last annotation says this should be forbidden. */
3768 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
3769 pedwarn ("ISO C++ forbids %sing an enum",
3770 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3771 ? "increment" : "decrement");
3773 /* Compute the increment. */
3775 if (TREE_CODE (argtype) == POINTER_TYPE)
3777 tree type = complete_type (TREE_TYPE (argtype));
3779 if (!COMPLETE_OR_VOID_TYPE_P (type))
3780 error ("cannot %s a pointer to incomplete type `%T'",
3781 ((code == PREINCREMENT_EXPR
3782 || code == POSTINCREMENT_EXPR)
3783 ? "increment" : "decrement"), TREE_TYPE (argtype));
3784 else if ((pedantic || warn_pointer_arith)
3785 && !TYPE_PTROB_P (argtype))
3786 pedwarn ("ISO C++ forbids %sing a pointer of type `%T'",
3787 ((code == PREINCREMENT_EXPR
3788 || code == POSTINCREMENT_EXPR)
3789 ? "increment" : "decrement"), argtype);
3790 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
3793 inc = integer_one_node;
3795 inc = cp_convert (argtype, inc);
3797 /* Handle incrementing a cast-expression. */
3799 switch (TREE_CODE (arg))
3804 case FIX_TRUNC_EXPR:
3805 case FIX_FLOOR_EXPR:
3806 case FIX_ROUND_EXPR:
3809 tree incremented, modify, value, compound;
3810 if (! lvalue_p (arg) && pedantic)
3811 pedwarn ("cast to non-reference type used as lvalue");
3812 arg = stabilize_reference (arg);
3813 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
3816 value = save_expr (arg);
3817 incremented = build (((code == PREINCREMENT_EXPR
3818 || code == POSTINCREMENT_EXPR)
3819 ? PLUS_EXPR : MINUS_EXPR),
3820 argtype, value, inc);
3822 modify = build_modify_expr (arg, NOP_EXPR, incremented);
3823 compound = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
3825 /* Eliminate warning about unused result of + or -. */
3826 TREE_NO_UNUSED_WARNING (compound) = 1;
3834 /* Complain about anything else that is not a true lvalue. */
3835 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
3836 || code == POSTINCREMENT_EXPR)
3837 ? "increment" : "decrement")))
3838 return error_mark_node;
3840 /* Forbid using -- on `bool'. */
3841 if (TREE_TYPE (arg) == boolean_type_node)
3843 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
3845 error ("invalid use of `--' on bool variable `%D'", arg);
3846 return error_mark_node;
3848 val = boolean_increment (code, arg);
3851 val = build (code, TREE_TYPE (arg), arg, inc);
3853 TREE_SIDE_EFFECTS (val) = 1;
3854 return cp_convert (result_type, val);
3858 /* Note that this operation never does default_conversion
3859 regardless of NOCONVERT. */
3861 argtype = lvalue_type (arg);
3863 if (TREE_CODE (arg) == OFFSET_REF)
3866 if (TREE_CODE (argtype) == REFERENCE_TYPE)
3870 build_pointer_type (TREE_TYPE (argtype)), arg);
3871 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3874 else if (pedantic && DECL_MAIN_P (arg))
3876 pedwarn ("ISO C++ forbids taking address of function `::main'");
3878 /* Let &* cancel out to simplify resulting code. */
3879 if (TREE_CODE (arg) == INDIRECT_REF)
3881 /* We don't need to have `current_class_ptr' wrapped in a
3882 NON_LVALUE_EXPR node. */
3883 if (arg == current_class_ref)
3884 return current_class_ptr;
3886 arg = TREE_OPERAND (arg, 0);
3887 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
3891 build_pointer_type (TREE_TYPE (TREE_TYPE (arg))), arg);
3892 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3894 else if (lvalue_p (arg))
3895 /* Don't let this be an lvalue. */
3896 return non_lvalue (arg);
3900 /* For &x[y], return x+y */
3901 if (TREE_CODE (arg) == ARRAY_REF)
3903 if (!cxx_mark_addressable (TREE_OPERAND (arg, 0)))
3904 return error_mark_node;
3905 return cp_build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
3906 TREE_OPERAND (arg, 1));
3909 /* Uninstantiated types are all functions. Taking the
3910 address of a function is a no-op, so just return the
3913 if (TREE_CODE (arg) == IDENTIFIER_NODE
3914 && IDENTIFIER_OPNAME_P (arg))
3917 /* We don't know the type yet, so just work around the problem.
3918 We know that this will resolve to an lvalue. */
3919 return build1 (ADDR_EXPR, unknown_type_node, arg);
3922 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
3923 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
3925 /* They're trying to take the address of a unique non-static
3926 member function. This is ill-formed (except in MS-land),
3927 but let's try to DTRT.
3928 Note: We only handle unique functions here because we don't
3929 want to complain if there's a static overload; non-unique
3930 cases will be handled by instantiate_type. But we need to
3931 handle this case here to allow casts on the resulting PMF.
3932 We could defer this in non-MS mode, but it's easier to give
3933 a useful error here. */
3935 /* Inside constant member functions, the `this' pointer
3936 contains an extra const qualifier. TYPE_MAIN_VARIANT
3937 is used here to remove this const from the diagnostics
3938 and the created OFFSET_REF. */
3939 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
3940 tree name = DECL_NAME (get_first_fn (TREE_OPERAND (arg, 1)));
3942 if (! flag_ms_extensions)
3944 if (current_class_type
3945 && TREE_OPERAND (arg, 0) == current_class_ref)
3946 /* An expression like &memfn. */
3947 pedwarn ("ISO C++ forbids taking the address of an unqualified"
3948 " or parenthesized non-static member function to form"
3949 " a pointer to member function. Say `&%T::%D'",
3952 pedwarn ("ISO C++ forbids taking the address of a bound member"
3953 " function to form a pointer to member function."
3957 arg = build_offset_ref (base, name, /*address_p=*/true);
3961 if (type_unknown_p (arg))
3962 return build1 (ADDR_EXPR, unknown_type_node, arg);
3964 /* Handle complex lvalues (when permitted)
3965 by reduction to simpler cases. */
3966 val = unary_complex_lvalue (code, arg);
3970 switch (TREE_CODE (arg))
3975 case FIX_TRUNC_EXPR:
3976 case FIX_FLOOR_EXPR:
3977 case FIX_ROUND_EXPR:
3979 if (! lvalue_p (arg) && pedantic)
3980 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
3987 /* Allow the address of a constructor if all the elements
3989 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_HAS_CONSTRUCTOR (arg)
3990 && TREE_CONSTANT (arg))
3992 /* Anything not already handled and not a true memory reference
3994 else if (TREE_CODE (argtype) != FUNCTION_TYPE
3995 && TREE_CODE (argtype) != METHOD_TYPE
3996 && !lvalue_or_else (arg, "unary `&'"))
3997 return error_mark_node;
3999 if (argtype != error_mark_node)
4000 argtype = build_pointer_type (argtype);
4005 if (TREE_CODE (arg) != COMPONENT_REF)
4006 addr = build_address (arg);
4007 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4009 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4011 /* We can only get here with a single static member
4013 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL
4014 && DECL_STATIC_FUNCTION_P (fn),
4017 addr = build_address (fn);
4018 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4019 /* Do not lose object's side effects. */
4020 addr = build (COMPOUND_EXPR, TREE_TYPE (addr),
4021 TREE_OPERAND (arg, 0), addr);
4023 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4025 error ("attempt to take address of bit-field structure member `%D'",
4026 TREE_OPERAND (arg, 1));
4027 return error_mark_node;
4031 /* Unfortunately we cannot just build an address
4032 expression here, because we would not handle
4033 address-constant-expressions or offsetof correctly. */
4034 tree field = TREE_OPERAND (arg, 1);
4035 tree rval = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
4036 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (rval)),
4037 decl_type_context (field),
4040 rval = build_base_path (PLUS_EXPR, rval, binfo, 1);
4041 rval = build_nop (argtype, rval);
4042 addr = fold (build (PLUS_EXPR, argtype, rval,
4043 cp_convert (argtype, byte_position (field))));
4046 if (TREE_CODE (argtype) == POINTER_TYPE
4047 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4049 build_ptrmemfunc_type (argtype);
4050 addr = build_ptrmemfunc (argtype, addr, 0);
4063 argtype = TREE_TYPE (arg);
4064 return fold (build1 (code, argtype, arg));
4067 error ("%s", errstring);
4068 return error_mark_node;
4071 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4072 for certain kinds of expressions which are not really lvalues
4073 but which we can accept as lvalues.
4075 If ARG is not a kind of expression we can handle, return zero. */
4078 unary_complex_lvalue (enum tree_code code, tree arg)
4080 /* Handle (a, b) used as an "lvalue". */
4081 if (TREE_CODE (arg) == COMPOUND_EXPR)
4083 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4084 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
4085 TREE_OPERAND (arg, 0), real_result);
4088 /* Handle (a ? b : c) used as an "lvalue". */
4089 if (TREE_CODE (arg) == COND_EXPR
4090 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4091 return rationalize_conditional_expr (code, arg);
4093 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4094 if (TREE_CODE (arg) == MODIFY_EXPR
4095 || TREE_CODE (arg) == PREINCREMENT_EXPR
4096 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4098 tree lvalue = TREE_OPERAND (arg, 0);
4099 if (TREE_SIDE_EFFECTS (lvalue))
4101 lvalue = stabilize_reference (lvalue);
4102 arg = build (TREE_CODE (arg), TREE_TYPE (arg),
4103 lvalue, TREE_OPERAND (arg, 1));
4105 return unary_complex_lvalue
4106 (code, build (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4109 if (code != ADDR_EXPR)
4112 /* Handle (a = b) used as an "lvalue" for `&'. */
4113 if (TREE_CODE (arg) == MODIFY_EXPR
4114 || TREE_CODE (arg) == INIT_EXPR)
4116 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4117 arg = build (COMPOUND_EXPR, TREE_TYPE (real_result), arg, real_result);
4118 TREE_NO_UNUSED_WARNING (arg) = 1;
4122 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4123 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4124 || TREE_CODE (arg) == OFFSET_REF)
4128 my_friendly_assert (TREE_CODE (arg) != SCOPE_REF, 313);
4130 if (TREE_CODE (arg) != OFFSET_REF)
4133 t = TREE_OPERAND (arg, 1);
4135 /* Check all this code for right semantics. */
4136 if (TREE_CODE (t) == FUNCTION_DECL)
4138 if (DECL_DESTRUCTOR_P (t))
4139 error ("taking address of destructor");
4140 return build_unary_op (ADDR_EXPR, t, 0);
4142 if (TREE_CODE (t) == VAR_DECL)
4143 return build_unary_op (ADDR_EXPR, t, 0);
4148 if (TREE_OPERAND (arg, 0)
4149 && ! is_dummy_object (TREE_OPERAND (arg, 0))
4150 && TREE_CODE (t) != FIELD_DECL)
4152 error ("taking address of bound pointer-to-member expression");
4153 return error_mark_node;
4155 if (!PTRMEM_OK_P (arg))
4156 return build_unary_op (code, arg, 0);
4158 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4160 error ("cannot create pointer to reference member `%D'", t);
4161 return error_mark_node;
4164 type = build_ptrmem_type (DECL_FIELD_CONTEXT (t), TREE_TYPE (t));
4165 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4171 /* We permit compiler to make function calls returning
4172 objects of aggregate type look like lvalues. */
4176 if (TREE_CODE (targ) == SAVE_EXPR)
4177 targ = TREE_OPERAND (targ, 0);
4179 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4181 if (TREE_CODE (arg) == SAVE_EXPR)
4184 targ = build_cplus_new (TREE_TYPE (arg), arg);
4185 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4188 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4189 return build (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4190 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4193 /* Don't let anything else be handled specially. */
4197 /* Mark EXP saying that we need to be able to take the
4198 address of it; it should not be allocated in a register.
4199 Value is true if successful.
4201 C++: we do not allow `current_class_ptr' to be addressable. */
4204 cxx_mark_addressable (tree exp)
4206 register tree x = exp;
4209 switch (TREE_CODE (x))
4216 x = TREE_OPERAND (x, 0);
4220 if (x == current_class_ptr)
4222 error ("cannot take the address of `this', which is an rvalue expression");
4223 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later */
4229 /* Caller should not be trying to mark initialized
4230 constant fields addressable. */
4231 my_friendly_assert (DECL_LANG_SPECIFIC (x) == 0
4232 || DECL_IN_AGGR_P (x) == 0
4234 || DECL_EXTERNAL (x), 314);
4239 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4240 && !DECL_ARTIFICIAL (x) && extra_warnings)
4241 warning ("address requested for `%D', which is declared `register'",
4243 TREE_ADDRESSABLE (x) = 1;
4244 put_var_into_stack (x, /*rescan=*/true);
4248 TREE_ADDRESSABLE (x) = 1;
4249 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
4253 TREE_ADDRESSABLE (x) = 1;
4257 TREE_ADDRESSABLE (x) = 1;
4258 cxx_mark_addressable (TREE_OPERAND (x, 0));
4266 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4269 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4271 tree orig_ifexp = ifexp;
4272 tree orig_op1 = op1;
4273 tree orig_op2 = op2;
4276 if (processing_template_decl)
4278 /* The standard says that the expression is type-dependent if
4279 IFEXP is type-dependent, even though the eventual type of the
4280 expression doesn't dependent on IFEXP. */
4281 if (type_dependent_expression_p (ifexp)
4282 || type_dependent_expression_p (op1)
4283 || type_dependent_expression_p (op2))
4284 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4285 ifexp = build_non_dependent_expr (ifexp);
4286 op1 = build_non_dependent_expr (op1);
4287 op2 = build_non_dependent_expr (op2);
4290 expr = build_conditional_expr (ifexp, op1, op2);
4291 if (processing_template_decl && expr != error_mark_node)
4292 return build_min_non_dep (COND_EXPR, expr,
4293 orig_ifexp, orig_op1, orig_op2);
4297 /* Given a list of expressions, return a compound expression
4298 that performs them all and returns the value of the last of them. */
4300 tree build_x_compound_expr_from_list (tree list, const char *msg)
4302 tree expr = TREE_VALUE (list);
4304 if (TREE_CHAIN (list))
4307 pedwarn ("%s expression list treated as compound expression", msg);
4309 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4310 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4316 /* Handle overloading of the ',' operator when needed. */
4319 build_x_compound_expr (tree op1, tree op2)
4322 tree orig_op1 = op1;
4323 tree orig_op2 = op2;
4325 if (processing_template_decl)
4327 if (type_dependent_expression_p (op1)
4328 || type_dependent_expression_p (op2))
4329 return build_min_nt (COMPOUND_EXPR, op1, op2);
4330 op1 = build_non_dependent_expr (op1);
4331 op2 = build_non_dependent_expr (op2);
4334 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE);
4336 result = build_compound_expr (op1, op2);
4338 if (processing_template_decl && result != error_mark_node)
4339 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4344 /* Build a compound expression. */
4347 build_compound_expr (tree lhs, tree rhs)
4349 lhs = decl_constant_value (lhs);
4350 lhs = convert_to_void (lhs, "left-hand operand of comma");
4352 if (lhs == error_mark_node || rhs == error_mark_node)
4353 return error_mark_node;
4355 if (TREE_CODE (rhs) == TARGET_EXPR)
4357 /* If the rhs is a TARGET_EXPR, then build the compound
4358 expression inside the target_expr's initializer. This
4359 helps the compiler to eliminate unncessary temporaries. */
4360 tree init = TREE_OPERAND (rhs, 1);
4362 init = build (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4363 TREE_OPERAND (rhs, 1) = init;
4368 return build (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4371 /* Issue an error message if casting from SRC_TYPE to DEST_TYPE casts
4372 away constness. DESCRIPTION explains what operation is taking
4376 check_for_casting_away_constness (tree src_type, tree dest_type,
4377 const char *description)
4379 if (casts_away_constness (src_type, dest_type))
4380 error ("%s from type `%T' to type `%T' casts away constness",
4381 description, src_type, dest_type);
4384 /* Return an expression representing static_cast<TYPE>(EXPR). */
4387 build_static_cast (tree type, tree expr)
4392 if (type == error_mark_node || expr == error_mark_node)
4393 return error_mark_node;
4395 if (processing_template_decl)
4397 expr = build_min (STATIC_CAST_EXPR, type, expr);
4398 /* We don't know if it will or will not have side effects. */
4399 TREE_SIDE_EFFECTS (expr) = 1;
4403 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4404 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4405 if (TREE_CODE (type) != REFERENCE_TYPE
4406 && TREE_CODE (expr) == NOP_EXPR
4407 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4408 expr = TREE_OPERAND (expr, 0);
4410 intype = TREE_TYPE (expr);
4412 /* [expr.static.cast]
4414 An lvalue of type "cv1 B", where B is a class type, can be cast
4415 to type "reference to cv2 D", where D is a class derived (clause
4416 _class.derived_) from B, if a valid standard conversion from
4417 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4418 same cv-qualification as, or greater cv-qualification than, cv1,
4419 and B is not a virtual base class of D. */
4420 /* We check this case before checking the validity of "TYPE t =
4421 EXPR;" below because for this case:
4424 struct D : public B { D(const B&); };
4426 void f() { static_cast<const D&>(b); }
4428 we want to avoid constructing a new D. The standard is not
4429 completely clear about this issue, but our interpretation is
4430 consistent with other compilers. */
4431 if (TREE_CODE (type) == REFERENCE_TYPE
4432 && CLASS_TYPE_P (TREE_TYPE (type))
4433 && CLASS_TYPE_P (intype)
4434 && real_lvalue_p (expr)
4435 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4436 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4437 build_pointer_type (TYPE_MAIN_VARIANT
4438 (TREE_TYPE (type))))
4439 && at_least_as_qualified_p (TREE_TYPE (type), intype))
4441 /* There is a standard conversion from "D*" to "B*" even if "B"
4442 is ambiguous or inaccessible. Therefore, we ask lookup_base
4443 to check these conditions. */
4444 tree base = lookup_base (TREE_TYPE (type), intype, ba_check, NULL);
4446 /* Convert from "B*" to "D*". This function will check that "B"
4447 is not a virtual base of "D". */
4448 expr = build_base_path (MINUS_EXPR, build_address (expr),
4449 base, /*nonnull=*/false);
4450 /* Convert the pointer to a reference -- but then remember that
4451 there are no expressions with reference type in C++. */
4452 return convert_from_reference (build_nop (type, expr));
4455 /* [expr.static.cast]
4457 An expression e can be explicitly converted to a type T using a
4458 static_cast of the form static_cast<T>(e) if the declaration T
4459 t(e);" is well-formed, for some invented temporary variable
4461 result = perform_direct_initialization_if_possible (type, expr);
4463 return convert_from_reference (result);
4465 /* [expr.static.cast]
4467 Any expression can be explicitly converted to type cv void. */
4468 if (TREE_CODE (type) == VOID_TYPE)
4469 return convert_to_void (expr, /*implicit=*/NULL);
4471 /* [expr.static.cast]
4473 The inverse of any standard conversion sequence (clause _conv_),
4474 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4475 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4476 (_conv.bool_) conversions, can be performed explicitly using
4477 static_cast subject to the restriction that the explicit
4478 conversion does not cast away constness (_expr.const.cast_), and
4479 the following additional rules for specific cases: */
4480 /* For reference, the conversions not excluded are: integral
4481 promotions, floating point promotion, integral conversions,
4482 floating point conversions, floating-integral conversions,
4483 pointer conversions, and pointer to member conversions. */
4484 if ((ARITHMETIC_TYPE_P (type) && ARITHMETIC_TYPE_P (intype))
4487 A value of integral _or enumeration_ type can be explicitly
4488 converted to an enumeration type. */
4489 || (INTEGRAL_OR_ENUMERATION_TYPE_P (type)
4490 && INTEGRAL_OR_ENUMERATION_TYPE_P (intype)))
4491 /* Really, build_c_cast should defer to this function rather
4492 than the other way around. */
4493 return build_c_cast (type, expr);
4495 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4496 && CLASS_TYPE_P (TREE_TYPE (type))
4497 && CLASS_TYPE_P (TREE_TYPE (intype))
4498 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4499 (TREE_TYPE (intype))),
4500 build_pointer_type (TYPE_MAIN_VARIANT
4501 (TREE_TYPE (type)))))
4505 check_for_casting_away_constness (intype, type, "static_cast");
4506 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype), ba_check,
4508 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4511 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4512 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4519 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4520 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4522 if (TYPE_PTRMEM_P (type))
4524 t1 = (build_ptrmem_type
4526 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4527 t2 = (build_ptrmem_type
4529 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4536 if (can_convert (t1, t2))
4538 check_for_casting_away_constness (intype, type, "static_cast");
4539 if (TYPE_PTRMEM_P (type))
4543 if (TREE_CODE (expr) == PTRMEM_CST)
4544 expr = cplus_expand_constant (expr);
4545 delta = get_delta_difference (c1, c2, /*force=*/1);
4546 if (!integer_zerop (delta))
4547 expr = cp_build_binary_op (PLUS_EXPR,
4548 build_nop (ptrdiff_type_node, expr),
4550 return build_nop (type, expr);
4553 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4558 /* [expr.static.cast]
4560 An rvalue of type "pointer to cv void" can be explicitly
4561 converted to a pointer to object type. A value of type pointer
4562 to object converted to "pointer to cv void" and back to the
4563 original pointer type will have its original value. */
4564 if (TREE_CODE (intype) == POINTER_TYPE
4565 && VOID_TYPE_P (TREE_TYPE (intype))
4566 && TYPE_PTROB_P (type))
4568 check_for_casting_away_constness (intype, type, "static_cast");
4569 return build_nop (type, expr);
4572 error ("invalid static_cast from type `%T' to type `%T'", intype, type);
4573 return error_mark_node;
4577 build_reinterpret_cast (tree type, tree expr)
4581 if (type == error_mark_node || expr == error_mark_node)
4582 return error_mark_node;
4584 if (processing_template_decl)
4586 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
4588 if (!TREE_SIDE_EFFECTS (t)
4589 && type_dependent_expression_p (expr))
4590 /* There might turn out to be side effects inside expr. */
4591 TREE_SIDE_EFFECTS (t) = 1;
4595 if (TREE_CODE (type) != REFERENCE_TYPE)
4597 expr = decay_conversion (expr);
4599 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4600 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4601 if (TREE_CODE (expr) == NOP_EXPR
4602 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4603 expr = TREE_OPERAND (expr, 0);
4606 intype = TREE_TYPE (expr);
4608 if (TREE_CODE (type) == REFERENCE_TYPE)
4610 if (! real_lvalue_p (expr))
4612 error ("invalid reinterpret_cast of an rvalue expression of type `%T' to type `%T'", intype, type);
4613 return error_mark_node;
4615 expr = build_unary_op (ADDR_EXPR, expr, 0);
4616 if (expr != error_mark_node)
4617 expr = build_reinterpret_cast
4618 (build_pointer_type (TREE_TYPE (type)), expr);
4619 if (expr != error_mark_node)
4620 expr = build_indirect_ref (expr, 0);
4623 else if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4624 return build_static_cast (type, expr);
4626 if (TYPE_PTR_P (type) && (TREE_CODE (intype) == INTEGER_TYPE
4627 || TREE_CODE (intype) == ENUMERAL_TYPE))
4629 else if (TREE_CODE (type) == INTEGER_TYPE && TYPE_PTR_P (intype))
4631 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
4632 pedwarn ("reinterpret_cast from `%T' to `%T' loses precision",
4635 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
4636 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4638 expr = decl_constant_value (expr);
4639 return fold (build1 (NOP_EXPR, type, expr));
4641 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4642 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
4644 check_for_casting_away_constness (intype, type, "reinterpret_cast");
4645 expr = decl_constant_value (expr);
4646 return fold (build1 (NOP_EXPR, type, expr));
4648 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
4649 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
4651 pedwarn ("ISO C++ forbids casting between pointer-to-function and pointer-to-object");
4652 expr = decl_constant_value (expr);
4653 return fold (build1 (NOP_EXPR, type, expr));
4657 error ("invalid reinterpret_cast from type `%T' to type `%T'",
4659 return error_mark_node;
4662 return cp_convert (type, expr);
4666 build_const_cast (tree type, tree expr)
4670 if (type == error_mark_node || expr == error_mark_node)
4671 return error_mark_node;
4673 if (processing_template_decl)
4675 tree t = build_min (CONST_CAST_EXPR, type, expr);
4677 if (!TREE_SIDE_EFFECTS (t)
4678 && type_dependent_expression_p (expr))
4679 /* There might turn out to be side effects inside expr. */
4680 TREE_SIDE_EFFECTS (t) = 1;
4684 if (!POINTER_TYPE_P (type))
4685 error ("invalid use of const_cast with type `%T', which is not a pointer, reference, nor a pointer-to-data-member type", type);
4686 else if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4688 error ("invalid use of const_cast with type `%T', which is a pointer or reference to a function type", type);
4689 return error_mark_node;
4692 if (TREE_CODE (type) != REFERENCE_TYPE)
4694 expr = decay_conversion (expr);
4696 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4697 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4698 if (TREE_CODE (expr) == NOP_EXPR
4699 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4700 expr = TREE_OPERAND (expr, 0);
4703 intype = TREE_TYPE (expr);
4705 if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4706 return build_static_cast (type, expr);
4707 else if (TREE_CODE (type) == REFERENCE_TYPE)
4709 if (! real_lvalue_p (expr))
4711 error ("invalid const_cast of an rvalue of type `%T' to type `%T'", intype, type);
4712 return error_mark_node;
4715 if (comp_ptr_ttypes_const (TREE_TYPE (type), intype))
4717 expr = build_unary_op (ADDR_EXPR, expr, 0);
4718 expr = build1 (NOP_EXPR, type, expr);
4719 return convert_from_reference (expr);
4722 else if (((TREE_CODE (type) == POINTER_TYPE
4723 && TREE_CODE (intype) == POINTER_TYPE)
4724 || (TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype)))
4725 && comp_ptr_ttypes_const (TREE_TYPE (type), TREE_TYPE (intype)))
4726 return cp_convert (type, expr);
4728 error ("invalid const_cast from type `%T' to type `%T'", intype, type);
4729 return error_mark_node;
4732 /* Build an expression representing a cast to type TYPE of expression EXPR.
4734 ALLOW_NONCONVERTING is true if we should allow non-converting constructors
4735 when doing the cast. */
4738 build_c_cast (tree type, tree expr)
4740 register tree value = expr;
4743 if (type == error_mark_node || expr == error_mark_node)
4744 return error_mark_node;
4746 if (processing_template_decl)
4748 tree t = build_min (CAST_EXPR, type,
4749 tree_cons (NULL_TREE, value, NULL_TREE));
4750 /* We don't know if it will or will not have side effects. */
4751 TREE_SIDE_EFFECTS (t) = 1;
4755 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4756 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4757 if (TREE_CODE (type) != REFERENCE_TYPE
4758 && TREE_CODE (value) == NOP_EXPR
4759 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
4760 value = TREE_OPERAND (value, 0);
4762 if (TREE_CODE (type) == ARRAY_TYPE)
4764 /* Allow casting from T1* to T2[] because Cfront allows it.
4765 NIHCL uses it. It is not valid ISO C++ however. */
4766 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
4768 pedwarn ("ISO C++ forbids casting to an array type `%T'", type);
4769 type = build_pointer_type (TREE_TYPE (type));
4773 error ("ISO C++ forbids casting to an array type `%T'", type);
4774 return error_mark_node;
4778 if (TREE_CODE (type) == FUNCTION_TYPE
4779 || TREE_CODE (type) == METHOD_TYPE)
4781 error ("invalid cast to function type `%T'", type);
4782 return error_mark_node;
4785 if (TREE_CODE (type) == VOID_TYPE)
4787 /* Conversion to void does not cause any of the normal function to
4788 * pointer, array to pointer and lvalue to rvalue decays. */
4790 value = convert_to_void (value, /*implicit=*/NULL);
4794 if (!complete_type_or_else (type, NULL_TREE))
4795 return error_mark_node;
4797 /* Convert functions and arrays to pointers and
4798 convert references to their expanded types,
4799 but don't convert any other types. If, however, we are
4800 casting to a class type, there's no reason to do this: the
4801 cast will only succeed if there is a converting constructor,
4802 and the default conversions will be done at that point. In
4803 fact, doing the default conversion here is actually harmful
4807 struct S { S(const A&); };
4809 since we don't want the array-to-pointer conversion done. */
4810 if (!IS_AGGR_TYPE (type))
4812 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
4813 || (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE
4814 /* Don't do the default conversion on a ->* expression. */
4815 && ! (TREE_CODE (type) == POINTER_TYPE
4816 && bound_pmf_p (value)))
4817 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
4818 || TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4819 value = decay_conversion (value);
4821 else if (TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4822 /* However, even for class types, we still need to strip away
4823 the reference type, since the call to convert_force below
4824 does not expect the input expression to be of reference
4826 value = convert_from_reference (value);
4828 otype = TREE_TYPE (value);
4830 /* Optionally warn about potentially worrisome casts. */
4833 && TREE_CODE (type) == POINTER_TYPE
4834 && TREE_CODE (otype) == POINTER_TYPE
4835 && !at_least_as_qualified_p (TREE_TYPE (type),
4837 warning ("cast from `%T' to `%T' discards qualifiers from pointer target type",
4840 if (TREE_CODE (type) == INTEGER_TYPE
4841 && TYPE_PTR_P (otype)
4842 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
4843 warning ("cast from pointer to integer of different size");
4845 if (TYPE_PTR_P (type)
4846 && TREE_CODE (otype) == INTEGER_TYPE
4847 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
4848 /* Don't warn about converting any constant. */
4849 && !TREE_CONSTANT (value))
4850 warning ("cast to pointer from integer of different size");
4852 if (TREE_CODE (type) == REFERENCE_TYPE)
4853 value = (convert_from_reference
4854 (convert_to_reference (type, value, CONV_C_CAST,
4855 LOOKUP_COMPLAIN, NULL_TREE)));
4860 value = decl_constant_value (value);
4863 value = convert_force (type, value, CONV_C_CAST);
4865 /* Ignore any integer overflow caused by the cast. */
4866 if (TREE_CODE (value) == INTEGER_CST)
4868 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
4869 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
4873 /* Warn about possible alignment problems. Do this here when we will have
4874 instantiated any necessary template types. */
4875 if (STRICT_ALIGNMENT && warn_cast_align
4876 && TREE_CODE (type) == POINTER_TYPE
4877 && TREE_CODE (otype) == POINTER_TYPE
4878 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
4879 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
4880 && COMPLETE_TYPE_P (TREE_TYPE (otype))
4881 && COMPLETE_TYPE_P (TREE_TYPE (type))
4882 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
4883 warning ("cast from `%T' to `%T' increases required alignment of target type",
4886 /* Always produce some operator for an explicit cast,
4887 so we can tell (for -pedantic) that the cast is no lvalue. */
4888 if (TREE_CODE (type) != REFERENCE_TYPE && value == expr
4889 && real_lvalue_p (value))
4890 value = non_lvalue (value);
4895 /* Build an assignment expression of lvalue LHS from value RHS.
4896 MODIFYCODE is the code for a binary operator that we use
4897 to combine the old value of LHS with RHS to get the new value.
4898 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
4900 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
4903 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
4905 register tree result;
4907 tree lhstype = TREE_TYPE (lhs);
4908 tree olhstype = lhstype;
4911 /* Avoid duplicate error messages from operands that had errors. */
4912 if (lhs == error_mark_node || rhs == error_mark_node)
4913 return error_mark_node;
4915 /* Handle control structure constructs used as "lvalues". */
4916 switch (TREE_CODE (lhs))
4918 /* Handle --foo = 5; as these are valid constructs in C++ */
4919 case PREDECREMENT_EXPR:
4920 case PREINCREMENT_EXPR:
4921 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4922 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4923 stabilize_reference (TREE_OPERAND (lhs, 0)),
4924 TREE_OPERAND (lhs, 1));
4925 return build (COMPOUND_EXPR, lhstype,
4927 build_modify_expr (TREE_OPERAND (lhs, 0),
4930 /* Handle (a, b) used as an "lvalue". */
4932 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
4934 if (newrhs == error_mark_node)
4935 return error_mark_node;
4936 return build (COMPOUND_EXPR, lhstype,
4937 TREE_OPERAND (lhs, 0), newrhs);
4940 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4941 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4942 stabilize_reference (TREE_OPERAND (lhs, 0)),
4943 TREE_OPERAND (lhs, 1));
4944 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
4945 if (newrhs == error_mark_node)
4946 return error_mark_node;
4947 return build (COMPOUND_EXPR, lhstype, lhs, newrhs);
4949 /* Handle (a ? b : c) used as an "lvalue". */
4952 /* Produce (a ? (b = rhs) : (c = rhs))
4953 except that the RHS goes through a save-expr
4954 so the code to compute it is only emitted once. */
4956 tree preeval = NULL_TREE;
4958 rhs = stabilize_expr (rhs, &preeval);
4960 /* Check this here to avoid odd errors when trying to convert
4961 a throw to the type of the COND_EXPR. */
4962 if (!lvalue_or_else (lhs, "assignment"))
4963 return error_mark_node;
4965 cond = build_conditional_expr
4966 (TREE_OPERAND (lhs, 0),
4967 build_modify_expr (cp_convert (TREE_TYPE (lhs),
4968 TREE_OPERAND (lhs, 1)),
4970 build_modify_expr (cp_convert (TREE_TYPE (lhs),
4971 TREE_OPERAND (lhs, 2)),
4974 if (cond == error_mark_node)
4976 /* Make sure the code to compute the rhs comes out
4977 before the split. */
4978 return build (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
4985 if (modifycode == INIT_EXPR)
4987 if (TREE_CODE (rhs) == CONSTRUCTOR)
4989 my_friendly_assert (same_type_p (TREE_TYPE (rhs), lhstype),
4991 result = build (INIT_EXPR, lhstype, lhs, rhs);
4992 TREE_SIDE_EFFECTS (result) = 1;
4995 else if (! IS_AGGR_TYPE (lhstype))
4996 /* Do the default thing */;
4999 result = build_special_member_call (lhs, complete_ctor_identifier,
5000 build_tree_list (NULL_TREE, rhs),
5001 TYPE_BINFO (lhstype),
5003 if (result == NULL_TREE)
5004 return error_mark_node;
5010 if (TREE_CODE (lhstype) == REFERENCE_TYPE)
5012 lhs = convert_from_reference (lhs);
5013 olhstype = lhstype = TREE_TYPE (lhs);
5015 lhs = require_complete_type (lhs);
5016 if (lhs == error_mark_node)
5017 return error_mark_node;
5019 if (modifycode == NOP_EXPR)
5021 /* `operator=' is not an inheritable operator. */
5022 if (! IS_AGGR_TYPE (lhstype))
5023 /* Do the default thing */;
5026 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5027 lhs, rhs, make_node (NOP_EXPR));
5028 if (result == NULL_TREE)
5029 return error_mark_node;
5036 /* A binary op has been requested. Combine the old LHS
5037 value with the RHS producing the value we should actually
5038 store into the LHS. */
5040 my_friendly_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE),
5042 lhs = stabilize_reference (lhs);
5043 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5044 if (newrhs == error_mark_node)
5046 error (" in evaluation of `%Q(%#T, %#T)'", modifycode,
5047 TREE_TYPE (lhs), TREE_TYPE (rhs));
5048 return error_mark_node;
5051 /* Now it looks like a plain assignment. */
5052 modifycode = NOP_EXPR;
5054 my_friendly_assert (TREE_CODE (lhstype) != REFERENCE_TYPE, 20011220);
5055 my_friendly_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE,
5059 /* Handle a cast used as an "lvalue".
5060 We have already performed any binary operator using the value as cast.
5061 Now convert the result to the cast type of the lhs,
5062 and then true type of the lhs and store it there;
5063 then convert result back to the cast type to be the value
5064 of the assignment. */
5066 switch (TREE_CODE (lhs))
5071 case FIX_TRUNC_EXPR:
5072 case FIX_FLOOR_EXPR:
5073 case FIX_ROUND_EXPR:
5076 tree inner_lhs = TREE_OPERAND (lhs, 0);
5079 if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5080 || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE
5081 || TREE_CODE (TREE_TYPE (newrhs)) == METHOD_TYPE
5082 || TREE_CODE (TREE_TYPE (newrhs)) == OFFSET_TYPE)
5083 newrhs = decay_conversion (newrhs);
5085 /* ISO C++ 5.4/1: The result is an lvalue if T is a reference
5086 type, otherwise the result is an rvalue. */
5087 if (! lvalue_p (lhs))
5088 pedwarn ("ISO C++ forbids cast to non-reference type used as lvalue");
5090 result = build_modify_expr (inner_lhs, NOP_EXPR,
5091 cp_convert (TREE_TYPE (inner_lhs),
5092 cp_convert (lhstype, newrhs)));
5093 if (result == error_mark_node)
5095 return cp_convert (TREE_TYPE (lhs), result);
5102 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
5103 Reject anything strange now. */
5105 if (!lvalue_or_else (lhs, "assignment"))
5106 return error_mark_node;
5108 /* Warn about modifying something that is `const'. Don't warn if
5109 this is initialization. */
5110 if (modifycode != INIT_EXPR
5111 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5112 /* Functions are not modifiable, even though they are
5114 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5115 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5116 /* If it's an aggregate and any field is const, then it is
5117 effectively const. */
5118 || (CLASS_TYPE_P (lhstype)
5119 && C_TYPE_FIELDS_READONLY (lhstype))))
5120 readonly_error (lhs, "assignment", 0);
5122 /* If storing into a structure or union member, it has probably been
5123 given type `int'. Compute the type that would go with the actual
5124 amount of storage the member occupies. */
5126 if (TREE_CODE (lhs) == COMPONENT_REF
5127 && (TREE_CODE (lhstype) == INTEGER_TYPE
5128 || TREE_CODE (lhstype) == REAL_TYPE
5129 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5131 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5133 /* If storing in a field that is in actuality a short or narrower
5134 than one, we must store in the field in its actual type. */
5136 if (lhstype != TREE_TYPE (lhs))
5138 lhs = copy_node (lhs);
5139 TREE_TYPE (lhs) = lhstype;
5143 /* Convert new value to destination type. */
5145 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5149 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5150 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5152 error ("incompatible types in assignment of `%T' to `%T'",
5153 TREE_TYPE (rhs), lhstype);
5154 return error_mark_node;
5157 /* Allow array assignment in compiler-generated code. */
5158 if (! DECL_ARTIFICIAL (current_function_decl))
5159 pedwarn ("ISO C++ forbids assignment of arrays");
5161 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5162 ? 1 + (modifycode != INIT_EXPR): 0;
5163 return build_vec_init (lhs, NULL_TREE, newrhs, from_array);
5166 if (modifycode == INIT_EXPR)
5167 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5168 "initialization", NULL_TREE, 0);
5171 /* Avoid warnings on enum bit fields. */
5172 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5173 && TREE_CODE (lhstype) == INTEGER_TYPE)
5175 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5177 newrhs = convert_force (lhstype, newrhs, 0);
5180 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5182 if (TREE_CODE (newrhs) == CALL_EXPR
5183 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5184 newrhs = build_cplus_new (lhstype, newrhs);
5186 /* Can't initialize directly from a TARGET_EXPR, since that would
5187 cause the lhs to be constructed twice, and possibly result in
5188 accidental self-initialization. So we force the TARGET_EXPR to be
5189 expanded without a target. */
5190 if (TREE_CODE (newrhs) == TARGET_EXPR)
5191 newrhs = build (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5192 TREE_OPERAND (newrhs, 0));
5195 if (newrhs == error_mark_node)
5196 return error_mark_node;
5198 result = build (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5199 lhstype, lhs, newrhs);
5201 TREE_SIDE_EFFECTS (result) = 1;
5203 /* If we got the LHS in a different type for storing in,
5204 convert the result back to the nominal type of LHS
5205 so that the value we return always has the same type
5206 as the LHS argument. */
5208 if (olhstype == TREE_TYPE (result))
5210 /* Avoid warnings converting integral types back into enums
5211 for enum bit fields. */
5212 if (TREE_CODE (TREE_TYPE (result)) == INTEGER_TYPE
5213 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5215 result = build (COMPOUND_EXPR, olhstype, result, olhs);
5216 TREE_NO_UNUSED_WARNING (result) = 1;
5219 return convert_for_assignment (olhstype, result, "assignment",
5224 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5226 if (processing_template_decl)
5227 return build_min_nt (MODOP_EXPR, lhs,
5228 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5230 if (modifycode != NOP_EXPR)
5232 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5233 make_node (modifycode));
5237 return build_modify_expr (lhs, modifycode, rhs);
5241 /* Get difference in deltas for different pointer to member function
5242 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5243 the conversion is invalid, the constant is zero. If FORCE is true,
5244 then allow reverse conversions as well.
5246 Note that the naming of FROM and TO is kind of backwards; the return
5247 value is what we add to a TO in order to get a FROM. They are named
5248 this way because we call this function to find out how to convert from
5249 a pointer to member of FROM to a pointer to member of TO. */
5252 get_delta_difference (tree from, tree to, int force)
5258 binfo = lookup_base (to, from, ba_check, &kind);
5259 if (kind == bk_inaccessible || kind == bk_ambig)
5261 error (" in pointer to member function conversion");
5268 error_not_base_type (from, to);
5269 error (" in pointer to member conversion");
5272 binfo = lookup_base (from, to, ba_check, &kind);
5275 virt_binfo = binfo_from_vbase (binfo);
5278 /* This is a reinterpret cast, we choose to do nothing. */
5279 warning ("pointer to member cast via virtual base `%T'",
5280 BINFO_TYPE (virt_binfo));
5283 return convert_to_integer (ptrdiff_type_node,
5284 size_diffop (size_zero_node,
5285 BINFO_OFFSET (binfo)));
5288 virt_binfo = binfo_from_vbase (binfo);
5290 return convert_to_integer (ptrdiff_type_node, BINFO_OFFSET (binfo));
5292 /* This is a reinterpret cast, we choose to do nothing. */
5294 warning ("pointer to member cast via virtual base `%T'",
5295 BINFO_TYPE (virt_binfo));
5297 error ("pointer to member conversion via virtual base `%T'",
5298 BINFO_TYPE (virt_binfo));
5301 return convert_to_integer(ptrdiff_type_node, integer_zero_node);
5304 /* Return a constructor for the pointer-to-member-function TYPE using
5305 the other components as specified. */
5308 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5314 /* Pull the FIELD_DECLs out of the type. */
5315 pfn_field = TYPE_FIELDS (type);
5316 delta_field = TREE_CHAIN (pfn_field);
5318 /* Make sure DELTA has the type we want. */
5319 delta = convert_and_check (delta_type_node, delta);
5321 /* Finish creating the initializer. */
5322 u = tree_cons (pfn_field, pfn,
5323 build_tree_list (delta_field, delta));
5324 u = build_constructor (type, u);
5325 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) && TREE_CONSTANT (delta);
5326 TREE_STATIC (u) = (TREE_CONSTANT (u)
5327 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5329 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5334 /* Build a constructor for a pointer to member function. It can be
5335 used to initialize global variables, local variable, or used
5336 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5339 If FORCE is nonzero, then force this conversion, even if
5340 we would rather not do it. Usually set when using an explicit
5343 Return error_mark_node, if something goes wrong. */
5346 build_ptrmemfunc (tree type, tree pfn, int force)
5352 if (error_operand_p (pfn))
5353 return error_mark_node;
5355 pfn_type = TREE_TYPE (pfn);
5356 to_type = build_ptrmemfunc_type (type);
5358 /* Handle multiple conversions of pointer to member functions. */
5359 if (TYPE_PTRMEMFUNC_P (pfn_type))
5361 tree delta = NULL_TREE;
5362 tree npfn = NULL_TREE;
5366 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn))
5367 error ("invalid conversion to type `%T' from type `%T'",
5370 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5371 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5374 /* We don't have to do any conversion to convert a
5375 pointer-to-member to its own type. But, we don't want to
5376 just return a PTRMEM_CST if there's an explicit cast; that
5377 cast should make the expression an invalid template argument. */
5378 if (TREE_CODE (pfn) != PTRMEM_CST)
5380 if (same_type_p (to_type, pfn_type))
5382 else if (integer_zerop (n))
5383 return build_reinterpret_cast (to_type, pfn);
5386 if (TREE_SIDE_EFFECTS (pfn))
5387 pfn = save_expr (pfn);
5389 /* Obtain the function pointer and the current DELTA. */
5390 if (TREE_CODE (pfn) == PTRMEM_CST)
5391 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
5394 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
5395 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
5398 /* Just adjust the DELTA field. */
5399 my_friendly_assert (TREE_TYPE (delta) == ptrdiff_type_node, 20030727);
5400 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
5401 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
5402 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
5403 return build_ptrmemfunc1 (to_type, delta, npfn);
5406 /* Handle null pointer to member function conversions. */
5407 if (integer_zerop (pfn))
5409 pfn = build_c_cast (type, integer_zero_node);
5410 return build_ptrmemfunc1 (to_type,
5415 if (type_unknown_p (pfn))
5416 return instantiate_type (type, pfn, tf_error | tf_warning);
5418 fn = TREE_OPERAND (pfn, 0);
5419 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5420 return make_ptrmem_cst (to_type, fn);
5423 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
5426 ??? There is no consistency as to the types returned for the above
5427 values. Some code acts as if its a sizetype and some as if its
5428 integer_type_node. */
5431 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
5433 tree type = TREE_TYPE (cst);
5434 tree fn = PTRMEM_CST_MEMBER (cst);
5435 tree ptr_class, fn_class;
5437 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5439 /* The class that the function belongs to. */
5440 fn_class = DECL_CONTEXT (fn);
5442 /* The class that we're creating a pointer to member of. */
5443 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
5445 /* First, calculate the adjustment to the function's class. */
5446 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0);
5448 if (!DECL_VIRTUAL_P (fn))
5449 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
5452 /* If we're dealing with a virtual function, we have to adjust 'this'
5453 again, to point to the base which provides the vtable entry for
5454 fn; the call will do the opposite adjustment. */
5455 tree orig_class = DECL_CONTEXT (fn);
5456 tree binfo = binfo_or_else (orig_class, fn_class);
5457 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5458 *delta, BINFO_OFFSET (binfo)));
5460 /* We set PFN to the vtable offset at which the function can be
5461 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
5462 case delta is shifted left, and then incremented). */
5463 *pfn = DECL_VINDEX (fn);
5464 *pfn = fold (build (MULT_EXPR, integer_type_node, *pfn,
5465 TYPE_SIZE_UNIT (vtable_entry_type)));
5467 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
5469 case ptrmemfunc_vbit_in_pfn:
5470 *pfn = fold (build (PLUS_EXPR, integer_type_node, *pfn,
5474 case ptrmemfunc_vbit_in_delta:
5475 *delta = fold (build (LSHIFT_EXPR, TREE_TYPE (*delta),
5476 *delta, integer_one_node));
5477 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5478 *delta, integer_one_node));
5485 *pfn = fold (build1 (NOP_EXPR, TYPE_PTRMEMFUNC_FN_TYPE (type),
5490 /* Return an expression for PFN from the pointer-to-member function
5494 pfn_from_ptrmemfunc (tree t)
5496 if (TREE_CODE (t) == PTRMEM_CST)
5501 expand_ptrmemfunc_cst (t, &delta, &pfn);
5506 return build_ptrmemfunc_access_expr (t, pfn_identifier);
5509 /* Expression EXPR is about to be implicitly converted to TYPE. Warn
5510 if this is a potentially dangerous thing to do. Returns a possibly
5514 dubious_conversion_warnings (tree type, tree expr,
5515 const char *errtype, tree fndecl, int parmnum)
5517 type = non_reference (type);
5519 /* Issue warnings about peculiar, but valid, uses of NULL. */
5520 if (ARITHMETIC_TYPE_P (type) && expr == null_node)
5523 warning ("passing NULL used for non-pointer %s %P of `%D'",
5524 errtype, parmnum, fndecl);
5526 warning ("%s to non-pointer type `%T' from NULL", errtype, type);
5529 /* Warn about assigning a floating-point type to an integer type. */
5530 if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE
5531 && TREE_CODE (type) == INTEGER_TYPE)
5534 warning ("passing `%T' for %s %P of `%D'",
5535 TREE_TYPE (expr), errtype, parmnum, fndecl);
5537 warning ("%s to `%T' from `%T'", errtype, type, TREE_TYPE (expr));
5539 /* And warn about assigning a negative value to an unsigned
5541 else if (TREE_UNSIGNED (type) && TREE_CODE (type) != BOOLEAN_TYPE)
5543 if (TREE_CODE (expr) == INTEGER_CST
5544 && TREE_NEGATED_INT (expr))
5547 warning ("passing negative value `%E' for %s %P of `%D'",
5548 expr, errtype, parmnum, fndecl);
5550 warning ("%s of negative value `%E' to `%T'",
5551 errtype, expr, type);
5554 overflow_warning (expr);
5556 if (TREE_CONSTANT (expr))
5562 /* Convert value RHS to type TYPE as preparation for an assignment to
5563 an lvalue of type TYPE. ERRTYPE is a string to use in error
5564 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
5565 are doing the conversion in order to pass the PARMNUMth argument of
5569 convert_for_assignment (tree type, tree rhs,
5570 const char *errtype, tree fndecl, int parmnum)
5572 register tree rhstype;
5573 register enum tree_code coder;
5575 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
5576 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
5577 rhs = TREE_OPERAND (rhs, 0);
5579 rhstype = TREE_TYPE (rhs);
5580 coder = TREE_CODE (rhstype);
5582 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
5583 && ((*targetm.vector_opaque_p) (type)
5584 || (*targetm.vector_opaque_p) (rhstype)))
5585 return convert (type, rhs);
5587 if (rhs == error_mark_node || rhstype == error_mark_node)
5588 return error_mark_node;
5589 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
5590 return error_mark_node;
5592 rhs = dubious_conversion_warnings (type, rhs, errtype, fndecl, parmnum);
5594 /* The RHS of an assignment cannot have void type. */
5595 if (coder == VOID_TYPE)
5597 error ("void value not ignored as it ought to be");
5598 return error_mark_node;
5601 /* Simplify the RHS if possible. */
5602 if (TREE_CODE (rhs) == CONST_DECL)
5603 rhs = DECL_INITIAL (rhs);
5605 /* We do not use decl_constant_value here because of this case:
5607 const char* const s = "s";
5609 The conversion rules for a string literal are more lax than for a
5610 variable; in particular, a string literal can be converted to a
5611 "char *" but the variable "s" cannot be converted in the same
5612 way. If the conversion is allowed, the optimization should be
5613 performed while creating the converted expression. */
5617 The expression is implicitly converted (clause _conv_) to the
5618 cv-unqualified type of the left operand.
5620 We allow bad conversions here because by the time we get to this point
5621 we are committed to doing the conversion. If we end up doing a bad
5622 conversion, convert_like will complain. */
5623 if (!can_convert_arg_bad (type, rhstype, rhs))
5625 /* When -Wno-pmf-conversions is use, we just silently allow
5626 conversions from pointers-to-members to plain pointers. If
5627 the conversion doesn't work, cp_convert will complain. */
5629 && TYPE_PTR_P (type)
5630 && TYPE_PTRMEMFUNC_P (rhstype))
5631 rhs = cp_convert (strip_top_quals (type), rhs);
5634 /* If the right-hand side has unknown type, then it is an
5635 overloaded function. Call instantiate_type to get error
5637 if (rhstype == unknown_type_node)
5638 instantiate_type (type, rhs, tf_error | tf_warning);
5640 error ("cannot convert `%T' to `%T' for argument `%P' to `%D'",
5641 rhstype, type, parmnum, fndecl);
5643 error ("cannot convert `%T' to `%T' in %s", rhstype, type,
5645 return error_mark_node;
5648 return perform_implicit_conversion (strip_top_quals (type), rhs);
5651 /* Convert RHS to be of type TYPE.
5652 If EXP is nonzero, it is the target of the initialization.
5653 ERRTYPE is a string to use in error messages.
5655 Two major differences between the behavior of
5656 `convert_for_assignment' and `convert_for_initialization'
5657 are that references are bashed in the former, while
5658 copied in the latter, and aggregates are assigned in
5659 the former (operator=) while initialized in the
5662 If using constructor make sure no conversion operator exists, if one does
5663 exist, an ambiguity exists.
5665 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
5668 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
5669 const char *errtype, tree fndecl, int parmnum)
5671 register enum tree_code codel = TREE_CODE (type);
5672 register tree rhstype;
5673 register enum tree_code coder;
5675 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5676 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
5677 if (TREE_CODE (rhs) == NOP_EXPR
5678 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
5679 && codel != REFERENCE_TYPE)
5680 rhs = TREE_OPERAND (rhs, 0);
5682 if (rhs == error_mark_node
5683 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
5684 return error_mark_node;
5686 if (TREE_CODE (TREE_TYPE (rhs)) == REFERENCE_TYPE)
5687 rhs = convert_from_reference (rhs);
5689 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
5690 && TREE_CODE (type) != ARRAY_TYPE
5691 && (TREE_CODE (type) != REFERENCE_TYPE
5692 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
5693 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
5694 && (TREE_CODE (type) != REFERENCE_TYPE
5695 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
5696 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
5697 rhs = decay_conversion (rhs);
5699 rhstype = TREE_TYPE (rhs);
5700 coder = TREE_CODE (rhstype);
5702 if (coder == ERROR_MARK)
5703 return error_mark_node;
5705 /* We accept references to incomplete types, so we can
5706 return here before checking if RHS is of complete type. */
5708 if (codel == REFERENCE_TYPE)
5710 /* This should eventually happen in convert_arguments. */
5711 int savew = 0, savee = 0;
5714 savew = warningcount, savee = errorcount;
5715 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
5719 if (warningcount > savew)
5720 cp_warning_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5721 else if (errorcount > savee)
5722 cp_error_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5728 exp = require_complete_type (exp);
5729 if (exp == error_mark_node)
5730 return error_mark_node;
5732 rhstype = non_reference (rhstype);
5734 type = complete_type (type);
5736 if (IS_AGGR_TYPE (type))
5737 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
5739 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
5742 /* Expand an ASM statement with operands, handling output operands
5743 that are not variables or INDIRECT_REFS by transforming such
5744 cases into cases that expand_asm_operands can handle.
5746 Arguments are same as for expand_asm_operands.
5748 We don't do default conversions on all inputs, because it can screw
5749 up operands that are expected to be in memory. */
5752 c_expand_asm_operands (tree string, tree outputs, tree inputs, tree clobbers,
5753 int vol, const char *filename, int line)
5755 int noutputs = list_length (outputs);
5757 /* o[I] is the place that output number I should be written. */
5758 register tree *o = alloca (noutputs * sizeof (tree));
5761 /* Record the contents of OUTPUTS before it is modified. */
5762 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5763 o[i] = TREE_VALUE (tail);
5765 /* Generate the ASM_OPERANDS insn;
5766 store into the TREE_VALUEs of OUTPUTS some trees for
5767 where the values were actually stored. */
5768 expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line);
5770 /* Copy all the intermediate outputs into the specified outputs. */
5771 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5773 if (o[i] != TREE_VALUE (tail))
5775 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
5776 const0_rtx, VOIDmode, EXPAND_NORMAL);
5779 /* Restore the original value so that it's correct the next
5780 time we expand this function. */
5781 TREE_VALUE (tail) = o[i];
5783 /* Detect modification of read-only values.
5784 (Otherwise done by build_modify_expr.) */
5787 tree type = TREE_TYPE (o[i]);
5788 if (type != error_mark_node
5789 && (CP_TYPE_CONST_P (type)
5790 || (CLASS_TYPE_P (type) && C_TYPE_FIELDS_READONLY (type))))
5791 readonly_error (o[i], "modification by `asm'", 1);
5795 /* Those MODIFY_EXPRs could do autoincrements. */
5799 /* If RETVAL is the address of, or a reference to, a local variable or
5800 temporary give an appropriate warning. */
5803 maybe_warn_about_returning_address_of_local (tree retval)
5805 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
5806 tree whats_returned = retval;
5810 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
5811 whats_returned = TREE_OPERAND (whats_returned, 1);
5812 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
5813 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
5814 || TREE_CODE (whats_returned) == NOP_EXPR)
5815 whats_returned = TREE_OPERAND (whats_returned, 0);
5820 if (TREE_CODE (whats_returned) != ADDR_EXPR)
5822 whats_returned = TREE_OPERAND (whats_returned, 0);
5824 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5826 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
5827 || TREE_CODE (whats_returned) == TARGET_EXPR)
5829 warning ("returning reference to temporary");
5832 if (TREE_CODE (whats_returned) == VAR_DECL
5833 && DECL_NAME (whats_returned)
5834 && TEMP_NAME_P (DECL_NAME (whats_returned)))
5836 warning ("reference to non-lvalue returned");
5841 if (TREE_CODE (whats_returned) == VAR_DECL
5842 && DECL_NAME (whats_returned)
5843 && DECL_FUNCTION_SCOPE_P (whats_returned)
5844 && !(TREE_STATIC (whats_returned)
5845 || TREE_PUBLIC (whats_returned)))
5847 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5848 cp_warning_at ("reference to local variable `%D' returned",
5851 cp_warning_at ("address of local variable `%D' returned",
5857 /* Check that returning RETVAL from the current function is valid.
5858 Return an expression explicitly showing all conversions required to
5859 change RETVAL into the function return type, and to assign it to
5860 the DECL_RESULT for the function. */
5863 check_return_expr (tree retval)
5866 /* The type actually returned by the function, after any
5869 int fn_returns_value_p;
5871 /* A `volatile' function is one that isn't supposed to return, ever.
5872 (This is a G++ extension, used to get better code for functions
5873 that call the `volatile' function.) */
5874 if (TREE_THIS_VOLATILE (current_function_decl))
5875 warning ("function declared `noreturn' has a `return' statement");
5877 /* Check for various simple errors. */
5878 if (DECL_DESTRUCTOR_P (current_function_decl))
5881 error ("returning a value from a destructor");
5884 else if (DECL_CONSTRUCTOR_P (current_function_decl))
5886 if (in_function_try_handler)
5887 /* If a return statement appears in a handler of the
5888 function-try-block of a constructor, the program is ill-formed. */
5889 error ("cannot return from a handler of a function-try-block of a constructor");
5891 /* You can't return a value from a constructor. */
5892 error ("returning a value from a constructor");
5896 if (processing_template_decl)
5898 current_function_returns_value = 1;
5902 /* When no explicit return-value is given in a function with a named
5903 return value, the named return value is used. */
5904 result = DECL_RESULT (current_function_decl);
5905 valtype = TREE_TYPE (result);
5906 my_friendly_assert (valtype != NULL_TREE, 19990924);
5907 fn_returns_value_p = !VOID_TYPE_P (valtype);
5908 if (!retval && DECL_NAME (result) && fn_returns_value_p)
5911 /* Check for a return statement with no return value in a function
5912 that's supposed to return a value. */
5913 if (!retval && fn_returns_value_p)
5915 pedwarn ("return-statement with no value, in function returning '%T'",
5917 /* Clear this, so finish_function won't say that we reach the
5918 end of a non-void function (which we don't, we gave a
5920 current_function_returns_null = 0;
5922 /* Check for a return statement with a value in a function that
5923 isn't supposed to return a value. */
5924 else if (retval && !fn_returns_value_p)
5926 if (VOID_TYPE_P (TREE_TYPE (retval)))
5927 /* You can return a `void' value from a function of `void'
5928 type. In that case, we have to evaluate the expression for
5929 its side-effects. */
5930 finish_expr_stmt (retval);
5932 pedwarn ("return-statement with a value, in function "
5933 "returning 'void'");
5935 current_function_returns_null = 1;
5937 /* There's really no value to return, after all. */
5941 /* Remember that this function can sometimes return without a
5943 current_function_returns_null = 1;
5945 /* Remember that this function did return a value. */
5946 current_function_returns_value = 1;
5948 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
5949 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
5950 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
5951 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
5953 && null_ptr_cst_p (retval))
5954 warning ("`operator new' must not return NULL unless it is declared `throw()' (or -fcheck-new is in effect)");
5956 /* Effective C++ rule 15. See also start_function. */
5958 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR)
5959 && retval != current_class_ref)
5960 warning ("`operator=' should return a reference to `*this'");
5962 /* The fabled Named Return Value optimization, as per [class.copy]/15:
5964 [...] For a function with a class return type, if the expression
5965 in the return statement is the name of a local object, and the cv-
5966 unqualified type of the local object is the same as the function
5967 return type, an implementation is permitted to omit creating the tem-
5968 porary object to hold the function return value [...]
5970 So, if this is a value-returning function that always returns the same
5971 local variable, remember it.
5973 It might be nice to be more flexible, and choose the first suitable
5974 variable even if the function sometimes returns something else, but
5975 then we run the risk of clobbering the variable we chose if the other
5976 returned expression uses the chosen variable somehow. And people expect
5977 this restriction, anyway. (jason 2000-11-19)
5979 See finish_function, genrtl_start_function, and declare_return_variable
5980 for other pieces of this optimization. */
5982 if (fn_returns_value_p && flag_elide_constructors)
5984 if (retval != NULL_TREE
5985 && (current_function_return_value == NULL_TREE
5986 || current_function_return_value == retval)
5987 && TREE_CODE (retval) == VAR_DECL
5988 && DECL_CONTEXT (retval) == current_function_decl
5989 && ! TREE_STATIC (retval)
5990 && (DECL_ALIGN (retval)
5991 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
5992 && same_type_p ((TYPE_MAIN_VARIANT
5993 (TREE_TYPE (retval))),
5995 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
5996 current_function_return_value = retval;
5998 current_function_return_value = error_mark_node;
6001 /* We don't need to do any conversions when there's nothing being
6003 if (!retval || retval == error_mark_node)
6006 /* Do any required conversions. */
6007 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6008 /* No conversions are required. */
6012 /* The type the function is declared to return. */
6013 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6015 /* First convert the value to the function's return type, then
6016 to the type of return value's location to handle the
6017 case that functype is smaller than the valtype. */
6018 retval = convert_for_initialization
6019 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6020 "return", NULL_TREE, 0);
6021 retval = convert (valtype, retval);
6023 /* If the conversion failed, treat this just like `return;'. */
6024 if (retval == error_mark_node)
6026 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6027 else if (! current_function_returns_struct
6028 && TREE_CODE (retval) == TARGET_EXPR
6029 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6030 retval = build (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6031 TREE_OPERAND (retval, 0));
6033 maybe_warn_about_returning_address_of_local (retval);
6036 /* Actually copy the value returned into the appropriate location. */
6037 if (retval && retval != result)
6038 retval = build (INIT_EXPR, TREE_TYPE (result), result, retval);
6044 /* Returns nonzero if the pointer-type FROM can be converted to the
6045 pointer-type TO via a qualification conversion. If CONSTP is -1,
6046 then we return nonzero if the pointers are similar, and the
6047 cv-qualification signature of FROM is a proper subset of that of TO.
6049 If CONSTP is positive, then all outer pointers have been
6053 comp_ptr_ttypes_real (tree to, tree from, int constp)
6055 bool to_more_cv_qualified = false;
6057 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6059 if (TREE_CODE (to) != TREE_CODE (from))
6062 if (TREE_CODE (from) == OFFSET_TYPE
6063 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6064 TYPE_OFFSET_BASETYPE (to)))
6067 /* Const and volatile mean something different for function types,
6068 so the usual checks are not appropriate. */
6069 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6071 if (!at_least_as_qualified_p (to, from))
6074 if (!at_least_as_qualified_p (from, to))
6078 to_more_cv_qualified = true;
6082 constp &= TYPE_READONLY (to);
6085 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6086 return ((constp >= 0 || to_more_cv_qualified)
6087 && same_type_ignoring_top_level_qualifiers_p (to, from));
6091 /* When comparing, say, char ** to char const **, this function takes
6092 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6093 types to this function. */
6096 comp_ptr_ttypes (tree to, tree from)
6098 return comp_ptr_ttypes_real (to, from, 1);
6101 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6102 type or inheritance-related types, regardless of cv-quals. */
6105 ptr_reasonably_similar (tree to, tree from)
6107 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6109 /* Any target type is similar enough to void. */
6110 if (TREE_CODE (to) == VOID_TYPE
6111 || TREE_CODE (from) == VOID_TYPE)
6114 if (TREE_CODE (to) != TREE_CODE (from))
6117 if (TREE_CODE (from) == OFFSET_TYPE
6118 && comptypes (TYPE_OFFSET_BASETYPE (to),
6119 TYPE_OFFSET_BASETYPE (from),
6120 COMPARE_BASE | COMPARE_DERIVED))
6123 if (TREE_CODE (to) == INTEGER_TYPE
6124 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6127 if (TREE_CODE (to) == FUNCTION_TYPE)
6130 if (TREE_CODE (to) != POINTER_TYPE)
6132 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6133 COMPARE_BASE | COMPARE_DERIVED);
6137 /* Like comp_ptr_ttypes, for const_cast. */
6140 comp_ptr_ttypes_const (tree to, tree from)
6142 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6144 if (TREE_CODE (to) != TREE_CODE (from))
6147 if (TREE_CODE (from) == OFFSET_TYPE
6148 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6149 TYPE_OFFSET_BASETYPE (to)))
6152 if (TREE_CODE (to) != POINTER_TYPE)
6153 return same_type_ignoring_top_level_qualifiers_p (to, from);
6157 /* Returns the type qualifiers for this type, including the qualifiers on the
6158 elements for an array type. */
6161 cp_type_quals (tree type)
6163 type = strip_array_types (type);
6164 if (type == error_mark_node)
6165 return TYPE_UNQUALIFIED;
6166 return TYPE_QUALS (type);
6169 /* Returns nonzero if the TYPE contains a mutable member */
6172 cp_has_mutable_p (tree type)
6174 type = strip_array_types (type);
6176 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6179 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6180 exemplar types such that casting T1 to T2 is casting away castness
6181 if and only if there is no implicit conversion from T1 to T2. */
6184 casts_away_constness_r (tree *t1, tree *t2)
6189 /* [expr.const.cast]
6191 For multi-level pointer to members and multi-level mixed pointers
6192 and pointers to members (conv.qual), the "member" aspect of a
6193 pointer to member level is ignored when determining if a const
6194 cv-qualifier has been cast away. */
6195 if (TYPE_PTRMEM_P (*t1))
6196 *t1 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t1));
6197 if (TYPE_PTRMEM_P (*t2))
6198 *t2 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t2));
6200 /* [expr.const.cast]
6202 For two pointer types:
6204 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6205 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6208 casting from X1 to X2 casts away constness if, for a non-pointer
6209 type T there does not exist an implicit conversion (clause
6212 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6216 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6218 if (TREE_CODE (*t1) != POINTER_TYPE
6219 || TREE_CODE (*t2) != POINTER_TYPE)
6221 *t1 = cp_build_qualified_type (void_type_node,
6222 cp_type_quals (*t1));
6223 *t2 = cp_build_qualified_type (void_type_node,
6224 cp_type_quals (*t2));
6228 quals1 = cp_type_quals (*t1);
6229 quals2 = cp_type_quals (*t2);
6230 *t1 = TREE_TYPE (*t1);
6231 *t2 = TREE_TYPE (*t2);
6232 casts_away_constness_r (t1, t2);
6233 *t1 = build_pointer_type (*t1);
6234 *t2 = build_pointer_type (*t2);
6235 *t1 = cp_build_qualified_type (*t1, quals1);
6236 *t2 = cp_build_qualified_type (*t2, quals2);
6239 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6243 casts_away_constness (tree t1, tree t2)
6245 if (TREE_CODE (t2) == REFERENCE_TYPE)
6247 /* [expr.const.cast]
6249 Casting from an lvalue of type T1 to an lvalue of type T2
6250 using a reference cast casts away constness if a cast from an
6251 rvalue of type "pointer to T1" to the type "pointer to T2"
6252 casts away constness. */
6253 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6254 return casts_away_constness (build_pointer_type (t1),
6255 build_pointer_type (TREE_TYPE (t2)));
6258 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6259 /* [expr.const.cast]
6261 Casting from an rvalue of type "pointer to data member of X
6262 of type T1" to the type "pointer to data member of Y of type
6263 T2" casts away constness if a cast from an rvalue of type
6264 "pointer to T1" to the type "pointer to T2" casts away
6266 return casts_away_constness
6267 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6268 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6270 /* Casting away constness is only something that makes sense for
6271 pointer or reference types. */
6272 if (TREE_CODE (t1) != POINTER_TYPE
6273 || TREE_CODE (t2) != POINTER_TYPE)
6276 /* Top-level qualifiers don't matter. */
6277 t1 = TYPE_MAIN_VARIANT (t1);
6278 t2 = TYPE_MAIN_VARIANT (t2);
6279 casts_away_constness_r (&t1, &t2);
6280 if (!can_convert (t2, t1))
6286 /* If T is a REFERENCE_TYPE return the type to which T refers.
6287 Otherwise, return T itself. */
6290 non_reference (tree t)
6292 if (TREE_CODE (t) == REFERENCE_TYPE)