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);
1864 if (TREE_CODE (name) == OVERLOAD)
1865 name = DECL_NAME (get_first_fn (name));
1866 else if (DECL_P (name))
1867 name = DECL_NAME (name);
1870 if (TREE_CODE (name) == SCOPE_REF)
1872 /* A qualified name. The qualifying class or namespace `S' has
1873 already been looked up; it is either a TYPE or a
1874 NAMESPACE_DECL. The member name is either an IDENTIFIER_NODE
1875 or a BIT_NOT_EXPR. */
1876 scope = TREE_OPERAND (name, 0);
1877 name = TREE_OPERAND (name, 1);
1878 my_friendly_assert ((CLASS_TYPE_P (scope)
1879 || TREE_CODE (scope) == NAMESPACE_DECL),
1881 my_friendly_assert ((TREE_CODE (name) == IDENTIFIER_NODE
1882 || TREE_CODE (name) == BIT_NOT_EXPR),
1885 /* If SCOPE is a namespace, then the qualified name does not
1886 name a member of OBJECT_TYPE. */
1887 if (TREE_CODE (scope) == NAMESPACE_DECL)
1889 error ("`%D::%D' is not a member of `%T'",
1890 scope, name, object_type);
1891 return error_mark_node;
1894 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
1895 access_path = lookup_base (object_type, scope, ba_check, NULL);
1896 if (access_path == error_mark_node)
1897 return error_mark_node;
1900 error ("`%T' is not a base of `%T'", scope, object_type);
1901 return error_mark_node;
1907 access_path = object_type;
1910 if (TREE_CODE (name) == BIT_NOT_EXPR)
1911 member = lookup_destructor (object, scope, name);
1914 /* Look up the member. */
1915 member = lookup_member (access_path, name, /*protect=*/1,
1916 /*want_type=*/false);
1917 if (member == NULL_TREE)
1919 error ("'%D' has no member named '%E'", object_type, name);
1920 return error_mark_node;
1922 if (member == error_mark_node)
1923 return error_mark_node;
1928 tree template = member;
1930 if (BASELINK_P (template))
1931 template = lookup_template_function (template, template_args);
1934 error ("`%D' is not a member template function", name);
1935 return error_mark_node;
1940 if (TREE_DEPRECATED (member))
1941 warn_deprecated_use (member);
1943 expr = build_class_member_access_expr (object, member, access_path,
1944 /*preserve_reference=*/false);
1945 if (processing_template_decl && expr != error_mark_node)
1946 return build_min_non_dep (COMPONENT_REF, expr,
1947 orig_object, orig_name);
1951 /* Return an expression for the MEMBER_NAME field in the internal
1952 representation of PTRMEM, a pointer-to-member function. (Each
1953 pointer-to-member function type gets its own RECORD_TYPE so it is
1954 more convenient to access the fields by name than by FIELD_DECL.)
1955 This routine converts the NAME to a FIELD_DECL and then creates the
1956 node for the complete expression. */
1959 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
1965 /* This code is a stripped down version of
1966 build_class_member_access_expr. It does not work to use that
1967 routine directly because it expects the object to be of class
1969 ptrmem_type = TREE_TYPE (ptrmem);
1970 my_friendly_assert (TYPE_PTRMEMFUNC_P (ptrmem_type), 20020804);
1971 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
1972 /*want_type=*/false);
1973 member_type = cp_build_qualified_type (TREE_TYPE (member),
1974 cp_type_quals (ptrmem_type));
1975 return fold (build (COMPONENT_REF, member_type, ptrmem, member));
1978 /* Given an expression PTR for a pointer, return an expression
1979 for the value pointed to.
1980 ERRORSTRING is the name of the operator to appear in error messages.
1982 This function may need to overload OPERATOR_FNNAME.
1983 Must also handle REFERENCE_TYPEs for C++. */
1986 build_x_indirect_ref (tree expr, const char *errorstring)
1988 tree orig_expr = expr;
1991 if (processing_template_decl)
1993 if (type_dependent_expression_p (expr))
1994 return build_min_nt (INDIRECT_REF, expr);
1995 expr = build_non_dependent_expr (expr);
1998 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2001 rval = build_indirect_ref (expr, errorstring);
2003 if (processing_template_decl && rval != error_mark_node)
2004 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2010 build_indirect_ref (tree ptr, const char *errorstring)
2012 register tree pointer, type;
2014 if (ptr == error_mark_node)
2015 return error_mark_node;
2017 if (ptr == current_class_ptr)
2018 return current_class_ref;
2020 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2021 ? ptr : decay_conversion (ptr));
2022 type = TREE_TYPE (pointer);
2024 if (TYPE_PTR_P (type) || TREE_CODE (type) == REFERENCE_TYPE)
2028 If the type of the expression is "pointer to T," the type
2029 of the result is "T."
2031 We must use the canonical variant because certain parts of
2032 the back end, like fold, do pointer comparisons between
2034 tree t = canonical_type_variant (TREE_TYPE (type));
2036 if (VOID_TYPE_P (t))
2038 /* A pointer to incomplete type (other than cv void) can be
2039 dereferenced [expr.unary.op]/1 */
2040 error ("`%T' is not a pointer-to-object type", type);
2041 return error_mark_node;
2043 else if (TREE_CODE (pointer) == ADDR_EXPR
2044 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2045 /* The POINTER was something like `&x'. We simplify `*&x' to
2047 return TREE_OPERAND (pointer, 0);
2050 tree ref = build1 (INDIRECT_REF, t, pointer);
2052 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2053 so that we get the proper error message if the result is used
2054 to assign to. Also, &* is supposed to be a no-op. */
2055 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2056 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2057 TREE_SIDE_EFFECTS (ref)
2058 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2062 /* `pointer' won't be an error_mark_node if we were given a
2063 pointer to member, so it's cool to check for this here. */
2064 else if (TYPE_PTR_TO_MEMBER_P (type))
2065 error ("invalid use of `%s' on pointer to member", errorstring);
2066 else if (pointer != error_mark_node)
2069 error ("invalid type argument of `%s'", errorstring);
2071 error ("invalid type argument");
2073 return error_mark_node;
2076 /* This handles expressions of the form "a[i]", which denotes
2079 This is logically equivalent in C to *(a+i), but we may do it differently.
2080 If A is a variable or a member, we generate a primitive ARRAY_REF.
2081 This avoids forcing the array out of registers, and can work on
2082 arrays that are not lvalues (for example, members of structures returned
2085 If INDEX is of some user-defined type, it must be converted to
2086 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2087 will inherit the type of the array, which will be some pointer type. */
2090 build_array_ref (tree array, tree idx)
2094 error ("subscript missing in array reference");
2095 return error_mark_node;
2098 if (TREE_TYPE (array) == error_mark_node
2099 || TREE_TYPE (idx) == error_mark_node)
2100 return error_mark_node;
2102 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2104 switch (TREE_CODE (array))
2108 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2109 return build (COMPOUND_EXPR, TREE_TYPE (value),
2110 TREE_OPERAND (array, 0), value);
2114 return build_conditional_expr
2115 (TREE_OPERAND (array, 0),
2116 build_array_ref (TREE_OPERAND (array, 1), idx),
2117 build_array_ref (TREE_OPERAND (array, 2), idx));
2123 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
2124 && TREE_CODE (array) != INDIRECT_REF)
2128 /* Subscripting with type char is likely to lose
2129 on a machine where chars are signed.
2130 So warn on any machine, but optionally.
2131 Don't warn for unsigned char since that type is safe.
2132 Don't warn for signed char because anyone who uses that
2133 must have done so deliberately. */
2134 if (warn_char_subscripts
2135 && TYPE_MAIN_VARIANT (TREE_TYPE (idx)) == char_type_node)
2136 warning ("array subscript has type `char'");
2138 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2140 error ("array subscript is not an integer");
2141 return error_mark_node;
2144 /* Apply integral promotions *after* noticing character types.
2145 (It is unclear why we do these promotions -- the standard
2146 does not say that we should. In fact, the natual thing would
2147 seem to be to convert IDX to ptrdiff_t; we're performing
2148 pointer arithmetic.) */
2149 idx = perform_integral_promotions (idx);
2151 /* An array that is indexed by a non-constant
2152 cannot be stored in a register; we must be able to do
2153 address arithmetic on its address.
2154 Likewise an array of elements of variable size. */
2155 if (TREE_CODE (idx) != INTEGER_CST
2156 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2157 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2160 if (!cxx_mark_addressable (array))
2161 return error_mark_node;
2164 /* An array that is indexed by a constant value which is not within
2165 the array bounds cannot be stored in a register either; because we
2166 would get a crash in store_bit_field/extract_bit_field when trying
2167 to access a non-existent part of the register. */
2168 if (TREE_CODE (idx) == INTEGER_CST
2169 && TYPE_VALUES (TREE_TYPE (array))
2170 && ! int_fits_type_p (idx, TYPE_VALUES (TREE_TYPE (array))))
2172 if (!cxx_mark_addressable (array))
2173 return error_mark_node;
2176 if (pedantic && !lvalue_p (array))
2177 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2179 /* Note in C++ it is valid to subscript a `register' array, since
2180 it is valid to take the address of something with that
2181 storage specification. */
2185 while (TREE_CODE (foo) == COMPONENT_REF)
2186 foo = TREE_OPERAND (foo, 0);
2187 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2188 warning ("subscripting array declared `register'");
2191 type = TREE_TYPE (TREE_TYPE (array));
2192 rval = build (ARRAY_REF, type, array, idx);
2193 /* Array ref is const/volatile if the array elements are
2194 or if the array is.. */
2195 TREE_READONLY (rval)
2196 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2197 TREE_SIDE_EFFECTS (rval)
2198 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2199 TREE_THIS_VOLATILE (rval)
2200 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2201 return require_complete_type (fold (rval));
2205 tree ar = default_conversion (array);
2206 tree ind = default_conversion (idx);
2208 /* Put the integer in IND to simplify error checking. */
2209 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2216 if (ar == error_mark_node)
2219 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2221 error ("subscripted value is neither array nor pointer");
2222 return error_mark_node;
2224 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2226 error ("array subscript is not an integer");
2227 return error_mark_node;
2230 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2235 /* Resolve a pointer to member function. INSTANCE is the object
2236 instance to use, if the member points to a virtual member.
2238 This used to avoid checking for virtual functions if basetype
2239 has no virtual functions, according to an earlier ANSI draft.
2240 With the final ISO C++ rules, such an optimization is
2241 incorrect: A pointer to a derived member can be static_cast
2242 to pointer-to-base-member, as long as the dynamic object
2243 later has the right member. */
2246 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2248 if (TREE_CODE (function) == OFFSET_REF)
2249 function = TREE_OPERAND (function, 1);
2251 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2253 tree idx, delta, e1, e2, e3, vtbl, basetype;
2254 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2256 tree instance_ptr = *instance_ptrptr;
2257 tree instance_save_expr = 0;
2258 if (instance_ptr == error_mark_node)
2260 if (TREE_CODE (function) == PTRMEM_CST)
2262 /* Extracting the function address from a pmf is only
2263 allowed with -Wno-pmf-conversions. It only works for
2265 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2266 e1 = convert (fntype, e1);
2271 error ("object missing in use of `%E'", function);
2272 return error_mark_node;
2276 if (TREE_SIDE_EFFECTS (instance_ptr))
2277 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2279 if (TREE_SIDE_EFFECTS (function))
2280 function = save_expr (function);
2282 /* Start by extracting all the information from the PMF itself. */
2283 e3 = PFN_FROM_PTRMEMFUNC (function);
2284 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2285 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2286 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2288 case ptrmemfunc_vbit_in_pfn:
2289 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2290 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2293 case ptrmemfunc_vbit_in_delta:
2294 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2295 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2302 /* Convert down to the right base before using the instance. First
2304 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2305 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2306 basetype, ba_check, NULL);
2307 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype, 1);
2308 if (instance_ptr == error_mark_node)
2309 return error_mark_node;
2310 /* ...and then the delta in the PMF. */
2311 instance_ptr = build (PLUS_EXPR, TREE_TYPE (instance_ptr),
2312 instance_ptr, delta);
2314 /* Hand back the adjusted 'this' argument to our caller. */
2315 *instance_ptrptr = instance_ptr;
2317 /* Next extract the vtable pointer from the object. */
2318 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2320 vtbl = build_indirect_ref (vtbl, NULL);
2322 /* Finally, extract the function pointer from the vtable. */
2323 e2 = fold (build (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx));
2324 e2 = build_indirect_ref (e2, NULL);
2325 TREE_CONSTANT (e2) = 1;
2327 /* When using function descriptors, the address of the
2328 vtable entry is treated as a function pointer. */
2329 if (TARGET_VTABLE_USES_DESCRIPTORS)
2330 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2331 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2333 TREE_TYPE (e2) = TREE_TYPE (e3);
2334 e1 = build_conditional_expr (e1, e2, e3);
2336 /* Make sure this doesn't get evaluated first inside one of the
2337 branches of the COND_EXPR. */
2338 if (instance_save_expr)
2339 e1 = build (COMPOUND_EXPR, TREE_TYPE (e1),
2340 instance_save_expr, e1);
2348 build_function_call (tree function, tree params)
2350 register tree fntype, fndecl;
2351 register tree coerced_params;
2353 tree name = NULL_TREE, assembler_name = NULL_TREE;
2355 tree original = function;
2357 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2358 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2359 if (TREE_CODE (function) == NOP_EXPR
2360 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2361 function = TREE_OPERAND (function, 0);
2363 if (TREE_CODE (function) == FUNCTION_DECL)
2365 name = DECL_NAME (function);
2366 assembler_name = DECL_ASSEMBLER_NAME (function);
2368 mark_used (function);
2371 /* Convert anything with function type to a pointer-to-function. */
2372 if (pedantic && DECL_MAIN_P (function))
2373 pedwarn ("ISO C++ forbids calling `::main' from within program");
2375 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2376 (because calling an inline function does not mean the function
2377 needs to be separately compiled). */
2379 if (DECL_INLINE (function))
2380 function = inline_conversion (function);
2382 function = build_addr_func (function);
2388 function = build_addr_func (function);
2391 if (function == error_mark_node)
2392 return error_mark_node;
2394 fntype = TREE_TYPE (function);
2396 if (TYPE_PTRMEMFUNC_P (fntype))
2398 error ("must use .* or ->* to call pointer-to-member function in `%E (...)'",
2400 return error_mark_node;
2403 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2404 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2406 if (!((TREE_CODE (fntype) == POINTER_TYPE
2407 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2409 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2411 error ("`%E' cannot be used as a function", original);
2412 return error_mark_node;
2415 /* fntype now gets the type of function pointed to. */
2416 fntype = TREE_TYPE (fntype);
2418 /* Convert the parameters to the types declared in the
2419 function prototype, or apply default promotions. */
2421 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2422 params, fndecl, LOOKUP_NORMAL);
2423 if (coerced_params == error_mark_node)
2424 return error_mark_node;
2426 /* Check for errors in format strings. */
2429 check_function_format (NULL, TYPE_ATTRIBUTES (fntype), coerced_params);
2431 /* Recognize certain built-in functions so we can make tree-codes
2432 other than CALL_EXPR. We do this when it enables fold-const.c
2433 to do something useful. */
2435 if (TREE_CODE (function) == ADDR_EXPR
2436 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
2437 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
2439 result = expand_tree_builtin (TREE_OPERAND (function, 0),
2440 params, coerced_params);
2445 return build_cxx_call (function, params, coerced_params);
2448 /* Convert the actual parameter expressions in the list VALUES
2449 to the types in the list TYPELIST.
2450 If parmdecls is exhausted, or when an element has NULL as its type,
2451 perform the default conversions.
2453 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2455 This is also where warnings about wrong number of args are generated.
2457 Return a list of expressions for the parameters as converted.
2459 Both VALUES and the returned value are chains of TREE_LIST nodes
2460 with the elements of the list in the TREE_VALUE slots of those nodes.
2462 In C++, unspecified trailing parameters can be filled in with their
2463 default arguments, if such were specified. Do so here. */
2466 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2468 register tree typetail, valtail;
2469 register tree result = NULL_TREE;
2470 const char *called_thing = 0;
2473 /* Argument passing is always copy-initialization. */
2474 flags |= LOOKUP_ONLYCONVERTING;
2478 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2480 if (DECL_NAME (fndecl) == NULL_TREE
2481 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2482 called_thing = "constructor";
2484 called_thing = "member function";
2487 called_thing = "function";
2490 for (valtail = values, typetail = typelist;
2492 valtail = TREE_CHAIN (valtail), i++)
2494 register tree type = typetail ? TREE_VALUE (typetail) : 0;
2495 register tree val = TREE_VALUE (valtail);
2497 if (val == error_mark_node)
2498 return error_mark_node;
2500 if (type == void_type_node)
2504 cp_error_at ("too many arguments to %s `%+#D'", called_thing,
2506 error ("at this point in file");
2509 error ("too many arguments to function");
2510 /* In case anybody wants to know if this argument
2513 TREE_TYPE (tree_last (result)) = error_mark_node;
2517 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2518 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2519 if (TREE_CODE (val) == NOP_EXPR
2520 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2521 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2522 val = TREE_OPERAND (val, 0);
2524 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2526 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2527 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2528 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2529 val = decay_conversion (val);
2532 if (val == error_mark_node)
2533 return error_mark_node;
2537 /* Formal parm type is specified by a function prototype. */
2540 if (!COMPLETE_TYPE_P (complete_type (type)))
2543 error ("parameter %P of `%D' has incomplete type `%T'",
2546 error ("parameter %P has incomplete type `%T'", i, type);
2547 parmval = error_mark_node;
2551 parmval = convert_for_initialization
2552 (NULL_TREE, type, val, flags,
2553 "argument passing", fndecl, i);
2554 parmval = convert_for_arg_passing (type, parmval);
2557 if (parmval == error_mark_node)
2558 return error_mark_node;
2560 result = tree_cons (NULL_TREE, parmval, result);
2564 if (TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE)
2565 val = convert_from_reference (val);
2567 if (fndecl && DECL_BUILT_IN (fndecl)
2568 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2569 /* Don't do ellipsis conversion for __built_in_constant_p
2570 as this will result in spurious warnings for non-POD
2572 val = require_complete_type (val);
2574 val = convert_arg_to_ellipsis (val);
2576 result = tree_cons (NULL_TREE, val, result);
2580 typetail = TREE_CHAIN (typetail);
2583 if (typetail != 0 && typetail != void_list_node)
2585 /* See if there are default arguments that can be used */
2586 if (TREE_PURPOSE (typetail)
2587 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2589 for (; typetail != void_list_node; ++i)
2592 = convert_default_arg (TREE_VALUE (typetail),
2593 TREE_PURPOSE (typetail),
2596 if (parmval == error_mark_node)
2597 return error_mark_node;
2599 result = tree_cons (0, parmval, result);
2600 typetail = TREE_CHAIN (typetail);
2601 /* ends with `...'. */
2602 if (typetail == NULL_TREE)
2610 cp_error_at ("too few arguments to %s `%+#D'",
2611 called_thing, fndecl);
2612 error ("at this point in file");
2615 error ("too few arguments to function");
2616 return error_mark_list;
2620 return nreverse (result);
2623 /* Build a binary-operation expression, after performing default
2624 conversions on the operands. CODE is the kind of expression to build. */
2627 build_x_binary_op (enum tree_code code, tree arg1, tree arg2)
2636 if (processing_template_decl)
2638 if (type_dependent_expression_p (arg1)
2639 || type_dependent_expression_p (arg2))
2640 return build_min_nt (code, arg1, arg2);
2641 arg1 = build_non_dependent_expr (arg1);
2642 arg2 = build_non_dependent_expr (arg2);
2645 if (code == DOTSTAR_EXPR)
2646 expr = build_m_component_ref (arg1, arg2);
2648 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE);
2650 if (processing_template_decl && expr != error_mark_node)
2651 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2656 /* Build a binary-operation expression without default conversions.
2657 CODE is the kind of expression to build.
2658 This function differs from `build' in several ways:
2659 the data type of the result is computed and recorded in it,
2660 warnings are generated if arg data types are invalid,
2661 special handling for addition and subtraction of pointers is known,
2662 and some optimization is done (operations on narrow ints
2663 are done in the narrower type when that gives the same result).
2664 Constant folding is also done before the result is returned.
2666 Note that the operands will never have enumeral types
2667 because either they have just had the default conversions performed
2668 or they have both just been converted to some other type in which
2669 the arithmetic is to be done.
2671 C++: must do special pointer arithmetic when implementing
2672 multiple inheritance, and deal with pointer to member functions. */
2675 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2676 int convert_p ATTRIBUTE_UNUSED)
2679 register enum tree_code code0, code1;
2682 /* Expression code to give to the expression when it is built.
2683 Normally this is CODE, which is what the caller asked for,
2684 but in some special cases we change it. */
2685 register enum tree_code resultcode = code;
2687 /* Data type in which the computation is to be performed.
2688 In the simplest cases this is the common type of the arguments. */
2689 register tree result_type = NULL;
2691 /* Nonzero means operands have already been type-converted
2692 in whatever way is necessary.
2693 Zero means they need to be converted to RESULT_TYPE. */
2696 /* Nonzero means create the expression with this type, rather than
2698 tree build_type = 0;
2700 /* Nonzero means after finally constructing the expression
2701 convert it to this type. */
2702 tree final_type = 0;
2704 /* Nonzero if this is an operation like MIN or MAX which can
2705 safely be computed in short if both args are promoted shorts.
2706 Also implies COMMON.
2707 -1 indicates a bitwise operation; this makes a difference
2708 in the exact conditions for when it is safe to do the operation
2709 in a narrower mode. */
2712 /* Nonzero if this is a comparison operation;
2713 if both args are promoted shorts, compare the original shorts.
2714 Also implies COMMON. */
2715 int short_compare = 0;
2717 /* Nonzero if this is a right-shift operation, which can be computed on the
2718 original short and then promoted if the operand is a promoted short. */
2719 int short_shift = 0;
2721 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2724 /* Apply default conversions. */
2728 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2729 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2730 || code == TRUTH_XOR_EXPR)
2732 if (!really_overloaded_fn (op0))
2733 op0 = decay_conversion (op0);
2734 if (!really_overloaded_fn (op1))
2735 op1 = decay_conversion (op1);
2739 if (!really_overloaded_fn (op0))
2740 op0 = default_conversion (op0);
2741 if (!really_overloaded_fn (op1))
2742 op1 = default_conversion (op1);
2745 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2746 STRIP_TYPE_NOPS (op0);
2747 STRIP_TYPE_NOPS (op1);
2749 /* DTRT if one side is an overloaded function, but complain about it. */
2750 if (type_unknown_p (op0))
2752 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
2753 if (t != error_mark_node)
2755 pedwarn ("assuming cast to type `%T' from overloaded function",
2760 if (type_unknown_p (op1))
2762 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
2763 if (t != error_mark_node)
2765 pedwarn ("assuming cast to type `%T' from overloaded function",
2771 type0 = TREE_TYPE (op0);
2772 type1 = TREE_TYPE (op1);
2774 /* The expression codes of the data types of the arguments tell us
2775 whether the arguments are integers, floating, pointers, etc. */
2776 code0 = TREE_CODE (type0);
2777 code1 = TREE_CODE (type1);
2779 /* If an error was already reported for one of the arguments,
2780 avoid reporting another error. */
2782 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
2783 return error_mark_node;
2788 /* Handle the pointer + int case. */
2789 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2790 return cp_pointer_int_sum (PLUS_EXPR, op0, op1);
2791 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
2792 return cp_pointer_int_sum (PLUS_EXPR, op1, op0);
2798 /* Subtraction of two similar pointers.
2799 We must subtract them as integers, then divide by object size. */
2800 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
2801 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
2803 return pointer_diff (op0, op1, common_type (type0, type1));
2804 /* Handle pointer minus int. Just like pointer plus int. */
2805 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2806 return cp_pointer_int_sum (MINUS_EXPR, op0, op1);
2815 case TRUNC_DIV_EXPR:
2817 case FLOOR_DIV_EXPR:
2818 case ROUND_DIV_EXPR:
2819 case EXACT_DIV_EXPR:
2820 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2821 || code0 == COMPLEX_TYPE)
2822 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2823 || code1 == COMPLEX_TYPE))
2825 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
2826 warning ("division by zero in `%E / 0'", op0);
2827 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
2828 warning ("division by zero in `%E / 0.'", op0);
2830 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
2831 resultcode = RDIV_EXPR;
2833 /* When dividing two signed integers, we have to promote to int.
2834 unless we divide by a constant != -1. Note that default
2835 conversion will have been performed on the operands at this
2836 point, so we have to dig out the original type to find out if
2838 shorten = ((TREE_CODE (op0) == NOP_EXPR
2839 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2840 || (TREE_CODE (op1) == INTEGER_CST
2841 && ! integer_all_onesp (op1)));
2850 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2854 case TRUNC_MOD_EXPR:
2855 case FLOOR_MOD_EXPR:
2856 if (code1 == INTEGER_TYPE && integer_zerop (op1))
2857 warning ("division by zero in `%E %% 0'", op0);
2858 else if (code1 == REAL_TYPE && real_zerop (op1))
2859 warning ("division by zero in `%E %% 0.'", op0);
2861 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2863 /* Although it would be tempting to shorten always here, that loses
2864 on some targets, since the modulo instruction is undefined if the
2865 quotient can't be represented in the computation mode. We shorten
2866 only if unsigned or if dividing by something we know != -1. */
2867 shorten = ((TREE_CODE (op0) == NOP_EXPR
2868 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2869 || (TREE_CODE (op1) == INTEGER_CST
2870 && ! integer_all_onesp (op1)));
2875 case TRUTH_ANDIF_EXPR:
2876 case TRUTH_ORIF_EXPR:
2877 case TRUTH_AND_EXPR:
2879 result_type = boolean_type_node;
2882 /* Shift operations: result has same type as first operand;
2883 always convert second operand to int.
2884 Also set SHORT_SHIFT if shifting rightward. */
2887 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2889 result_type = type0;
2890 if (TREE_CODE (op1) == INTEGER_CST)
2892 if (tree_int_cst_lt (op1, integer_zero_node))
2893 warning ("right shift count is negative");
2896 if (! integer_zerop (op1))
2898 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2899 warning ("right shift count >= width of type");
2902 /* Convert the shift-count to an integer, regardless of
2903 size of value being shifted. */
2904 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2905 op1 = cp_convert (integer_type_node, op1);
2906 /* Avoid converting op1 to result_type later. */
2912 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2914 result_type = type0;
2915 if (TREE_CODE (op1) == INTEGER_CST)
2917 if (tree_int_cst_lt (op1, integer_zero_node))
2918 warning ("left shift count is negative");
2919 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2920 warning ("left shift count >= width of type");
2922 /* Convert the shift-count to an integer, regardless of
2923 size of value being shifted. */
2924 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2925 op1 = cp_convert (integer_type_node, op1);
2926 /* Avoid converting op1 to result_type later. */
2933 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2935 result_type = type0;
2936 if (TREE_CODE (op1) == INTEGER_CST)
2938 if (tree_int_cst_lt (op1, integer_zero_node))
2939 warning ("%s rotate count is negative",
2940 (code == LROTATE_EXPR) ? "left" : "right");
2941 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2942 warning ("%s rotate count >= width of type",
2943 (code == LROTATE_EXPR) ? "left" : "right");
2945 /* Convert the shift-count to an integer, regardless of
2946 size of value being shifted. */
2947 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2948 op1 = cp_convert (integer_type_node, op1);
2954 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
2955 warning ("comparing floating point with == or != is unsafe");
2957 build_type = boolean_type_node;
2958 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2959 || code0 == COMPLEX_TYPE)
2960 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2961 || code1 == COMPLEX_TYPE))
2963 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2964 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
2965 result_type = composite_pointer_type (type0, type1, op0, op1,
2967 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
2968 && null_ptr_cst_p (op1))
2969 result_type = type0;
2970 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
2971 && null_ptr_cst_p (op0))
2972 result_type = type1;
2973 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2975 result_type = type0;
2976 error ("ISO C++ forbids comparison between pointer and integer");
2978 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2980 result_type = type1;
2981 error ("ISO C++ forbids comparison between pointer and integer");
2983 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
2985 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
2986 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
2987 result_type = TREE_TYPE (op0);
2989 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
2990 return cp_build_binary_op (code, op1, op0);
2991 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
2992 && same_type_p (type0, type1))
2994 /* E will be the final comparison. */
2996 /* E1 and E2 are for scratch. */
3004 if (TREE_SIDE_EFFECTS (op0))
3005 op0 = save_expr (op0);
3006 if (TREE_SIDE_EFFECTS (op1))
3007 op1 = save_expr (op1);
3012 && (!op0.pfn || op0.delta == op1.delta))
3014 The reason for the `!op0.pfn' bit is that a NULL
3015 pointer-to-member is any member with a zero PFN; the
3016 DELTA field is unspecified. */
3017 pfn0 = pfn_from_ptrmemfunc (op0);
3018 pfn1 = pfn_from_ptrmemfunc (op1);
3019 delta0 = build_ptrmemfunc_access_expr (op0,
3021 delta1 = build_ptrmemfunc_access_expr (op1,
3023 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3024 e2 = cp_build_binary_op (EQ_EXPR,
3026 cp_convert (TREE_TYPE (pfn0),
3027 integer_zero_node));
3028 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3029 e2 = build (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3030 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3031 if (code == EQ_EXPR)
3033 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3035 else if ((TYPE_PTRMEMFUNC_P (type0)
3036 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0), type1))
3037 || (TYPE_PTRMEMFUNC_P (type1)
3038 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1), type0)))
3044 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3045 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3047 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3048 result_type = composite_pointer_type (type0, type1, op0, op1,
3056 build_type = boolean_type_node;
3057 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3058 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3060 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3061 result_type = composite_pointer_type (type0, type1, op0, op1,
3063 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3064 && integer_zerop (op1))
3065 result_type = type0;
3066 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3067 && integer_zerop (op0))
3068 result_type = type1;
3069 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3071 result_type = type0;
3072 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3074 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3076 result_type = type1;
3077 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3081 case UNORDERED_EXPR:
3088 build_type = integer_type_node;
3089 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3091 error ("unordered comparison on non-floating point argument");
3092 return error_mark_node;
3101 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3103 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
3105 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3107 if (shorten || common || short_compare)
3108 result_type = common_type (type0, type1);
3110 /* For certain operations (which identify themselves by shorten != 0)
3111 if both args were extended from the same smaller type,
3112 do the arithmetic in that type and then extend.
3114 shorten !=0 and !=1 indicates a bitwise operation.
3115 For them, this optimization is safe only if
3116 both args are zero-extended or both are sign-extended.
3117 Otherwise, we might change the result.
3118 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3119 but calculated in (unsigned short) it would be (unsigned short)-1. */
3121 if (shorten && none_complex)
3123 int unsigned0, unsigned1;
3124 tree arg0 = get_narrower (op0, &unsigned0);
3125 tree arg1 = get_narrower (op1, &unsigned1);
3126 /* UNS is 1 if the operation to be done is an unsigned one. */
3127 int uns = TREE_UNSIGNED (result_type);
3130 final_type = result_type;
3132 /* Handle the case that OP0 does not *contain* a conversion
3133 but it *requires* conversion to FINAL_TYPE. */
3135 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3136 unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
3137 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3138 unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
3140 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3142 /* For bitwise operations, signedness of nominal type
3143 does not matter. Consider only how operands were extended. */
3147 /* Note that in all three cases below we refrain from optimizing
3148 an unsigned operation on sign-extended args.
3149 That would not be valid. */
3151 /* Both args variable: if both extended in same way
3152 from same width, do it in that width.
3153 Do it unsigned if args were zero-extended. */
3154 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3155 < TYPE_PRECISION (result_type))
3156 && (TYPE_PRECISION (TREE_TYPE (arg1))
3157 == TYPE_PRECISION (TREE_TYPE (arg0)))
3158 && unsigned0 == unsigned1
3159 && (unsigned0 || !uns))
3160 result_type = c_common_signed_or_unsigned_type
3161 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3162 else if (TREE_CODE (arg0) == INTEGER_CST
3163 && (unsigned1 || !uns)
3164 && (TYPE_PRECISION (TREE_TYPE (arg1))
3165 < TYPE_PRECISION (result_type))
3166 && (type = c_common_signed_or_unsigned_type
3167 (unsigned1, TREE_TYPE (arg1)),
3168 int_fits_type_p (arg0, type)))
3170 else if (TREE_CODE (arg1) == INTEGER_CST
3171 && (unsigned0 || !uns)
3172 && (TYPE_PRECISION (TREE_TYPE (arg0))
3173 < TYPE_PRECISION (result_type))
3174 && (type = c_common_signed_or_unsigned_type
3175 (unsigned0, TREE_TYPE (arg0)),
3176 int_fits_type_p (arg1, type)))
3180 /* Shifts can be shortened if shifting right. */
3185 tree arg0 = get_narrower (op0, &unsigned_arg);
3187 final_type = result_type;
3189 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3190 unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
3192 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3193 /* We can shorten only if the shift count is less than the
3194 number of bits in the smaller type size. */
3195 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3196 /* If arg is sign-extended and then unsigned-shifted,
3197 we can simulate this with a signed shift in arg's type
3198 only if the extended result is at least twice as wide
3199 as the arg. Otherwise, the shift could use up all the
3200 ones made by sign-extension and bring in zeros.
3201 We can't optimize that case at all, but in most machines
3202 it never happens because available widths are 2**N. */
3203 && (!TREE_UNSIGNED (final_type)
3205 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3206 <= TYPE_PRECISION (result_type))))
3208 /* Do an unsigned shift if the operand was zero-extended. */
3210 = c_common_signed_or_unsigned_type (unsigned_arg,
3212 /* Convert value-to-be-shifted to that type. */
3213 if (TREE_TYPE (op0) != result_type)
3214 op0 = cp_convert (result_type, op0);
3219 /* Comparison operations are shortened too but differently.
3220 They identify themselves by setting short_compare = 1. */
3224 /* Don't write &op0, etc., because that would prevent op0
3225 from being kept in a register.
3226 Instead, make copies of the our local variables and
3227 pass the copies by reference, then copy them back afterward. */
3228 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3229 enum tree_code xresultcode = resultcode;
3231 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3233 return cp_convert (boolean_type_node, val);
3234 op0 = xop0, op1 = xop1;
3236 resultcode = xresultcode;
3239 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3240 && warn_sign_compare
3241 /* Do not warn until the template is instantiated; we cannot
3242 bound the ranges of the arguments until that point. */
3243 && !processing_template_decl)
3245 int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0));
3246 int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1));
3248 int unsignedp0, unsignedp1;
3249 tree primop0 = get_narrower (op0, &unsignedp0);
3250 tree primop1 = get_narrower (op1, &unsignedp1);
3252 /* Check for comparison of different enum types. */
3253 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3254 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3255 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3256 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3258 warning ("comparison between types `%#T' and `%#T'",
3259 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3262 /* Give warnings for comparisons between signed and unsigned
3263 quantities that may fail. */
3264 /* Do the checking based on the original operand trees, so that
3265 casts will be considered, but default promotions won't be. */
3267 /* Do not warn if the comparison is being done in a signed type,
3268 since the signed type will only be chosen if it can represent
3269 all the values of the unsigned type. */
3270 if (! TREE_UNSIGNED (result_type))
3272 /* Do not warn if both operands are unsigned. */
3273 else if (op0_signed == op1_signed)
3275 /* Do not warn if the signed quantity is an unsuffixed
3276 integer literal (or some static constant expression
3277 involving such literals or a conditional expression
3278 involving such literals) and it is non-negative. */
3279 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3280 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3282 /* Do not warn if the comparison is an equality operation,
3283 the unsigned quantity is an integral constant and it does
3284 not use the most significant bit of result_type. */
3285 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3286 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3287 && int_fits_type_p (orig_op1, c_common_signed_type
3289 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3290 && int_fits_type_p (orig_op0, c_common_signed_type
3294 warning ("comparison between signed and unsigned integer expressions");
3296 /* Warn if two unsigned values are being compared in a size
3297 larger than their original size, and one (and only one) is the
3298 result of a `~' operator. This comparison will always fail.
3300 Also warn if one operand is a constant, and the constant does not
3301 have all bits set that are set in the ~ operand when it is
3304 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3305 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3307 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3308 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3309 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3310 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3312 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3315 HOST_WIDE_INT constant, mask;
3319 if (host_integerp (primop0, 0))
3322 unsignedp = unsignedp1;
3323 constant = tree_low_cst (primop0, 0);
3328 unsignedp = unsignedp0;
3329 constant = tree_low_cst (primop1, 0);
3332 bits = TYPE_PRECISION (TREE_TYPE (primop));
3333 if (bits < TYPE_PRECISION (result_type)
3334 && bits < HOST_BITS_PER_LONG && unsignedp)
3336 mask = (~ (HOST_WIDE_INT) 0) << bits;
3337 if ((mask & constant) != mask)
3338 warning ("comparison of promoted ~unsigned with constant");
3341 else if (unsignedp0 && unsignedp1
3342 && (TYPE_PRECISION (TREE_TYPE (primop0))
3343 < TYPE_PRECISION (result_type))
3344 && (TYPE_PRECISION (TREE_TYPE (primop1))
3345 < TYPE_PRECISION (result_type)))
3346 warning ("comparison of promoted ~unsigned with unsigned");
3351 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
3352 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3353 Then the expression will be built.
3354 It will be given type FINAL_TYPE if that is nonzero;
3355 otherwise, it will be given type RESULT_TYPE. */
3359 error ("invalid operands of types `%T' and `%T' to binary `%O'",
3360 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3361 return error_mark_node;
3364 /* Issue warnings about peculiar, but valid, uses of NULL. */
3365 if (/* It's reasonable to use pointer values as operands of &&
3366 and ||, so NULL is no exception. */
3367 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3368 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3369 (orig_op0 == null_node
3370 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3371 /* Or vice versa. */
3372 || (orig_op1 == null_node
3373 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3374 /* Or, both are NULL and the operation was not a comparison. */
3375 || (orig_op0 == null_node && orig_op1 == null_node
3376 && code != EQ_EXPR && code != NE_EXPR)))
3377 /* Some sort of arithmetic operation involving NULL was
3378 performed. Note that pointer-difference and pointer-addition
3379 have already been handled above, and so we don't end up here in
3381 warning ("NULL used in arithmetic");
3385 if (TREE_TYPE (op0) != result_type)
3386 op0 = cp_convert (result_type, op0);
3387 if (TREE_TYPE (op1) != result_type)
3388 op1 = cp_convert (result_type, op1);
3390 if (op0 == error_mark_node || op1 == error_mark_node)
3391 return error_mark_node;
3394 if (build_type == NULL_TREE)
3395 build_type = result_type;
3398 register tree result = build (resultcode, build_type, op0, op1);
3399 register tree folded;
3401 folded = fold (result);
3402 if (folded == result)
3403 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
3404 if (final_type != 0)
3405 return cp_convert (final_type, folded);
3410 /* Return a tree for the sum or difference (RESULTCODE says which)
3411 of pointer PTROP and integer INTOP. */
3414 cp_pointer_int_sum (enum tree_code resultcode, register tree ptrop,
3415 register tree intop)
3417 tree res_type = TREE_TYPE (ptrop);
3419 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3420 in certain circumstance (when it's valid to do so). So we need
3421 to make sure it's complete. We don't need to check here, if we
3422 can actually complete it at all, as those checks will be done in
3423 pointer_int_sum() anyway. */
3424 complete_type (TREE_TYPE (res_type));
3426 return pointer_int_sum (resultcode, ptrop, fold (intop));
3429 /* Return a tree for the difference of pointers OP0 and OP1.
3430 The resulting tree has type int. */
3433 pointer_diff (register tree op0, register tree op1, register tree ptrtype)
3435 register tree result, folded;
3436 tree restype = ptrdiff_type_node;
3437 tree target_type = TREE_TYPE (ptrtype);
3439 if (!complete_type_or_else (target_type, NULL_TREE))
3440 return error_mark_node;
3442 if (pedantic || warn_pointer_arith)
3444 if (TREE_CODE (target_type) == VOID_TYPE)
3445 pedwarn ("ISO C++ forbids using pointer of type `void *' in subtraction");
3446 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3447 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3448 if (TREE_CODE (target_type) == METHOD_TYPE)
3449 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3452 /* First do the subtraction as integers;
3453 then drop through to build the divide operator. */
3455 op0 = cp_build_binary_op (MINUS_EXPR,
3456 cp_convert (restype, op0),
3457 cp_convert (restype, op1));
3459 /* This generates an error if op1 is a pointer to an incomplete type. */
3460 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3461 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3463 op1 = (TYPE_PTROB_P (ptrtype)
3464 ? size_in_bytes (target_type)
3465 : integer_one_node);
3467 /* Do the division. */
3469 result = build (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3471 folded = fold (result);
3472 if (folded == result)
3473 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
3477 /* Construct and perhaps optimize a tree representation
3478 for a unary operation. CODE, a tree_code, specifies the operation
3479 and XARG is the operand. */
3482 build_x_unary_op (enum tree_code code, tree xarg)
3484 tree orig_expr = xarg;
3488 if (processing_template_decl)
3490 if (type_dependent_expression_p (xarg))
3491 return build_min_nt (code, xarg, NULL_TREE);
3492 xarg = build_non_dependent_expr (xarg);
3497 /* & rec, on incomplete RECORD_TYPEs is the simple opr &, not an
3499 if (code == ADDR_EXPR
3500 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3501 && ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (xarg)))
3502 && !COMPLETE_TYPE_P (TREE_TYPE (xarg)))
3503 || (TREE_CODE (xarg) == OFFSET_REF)))
3504 /* don't look for a function */;
3506 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE);
3507 if (!exp && code == ADDR_EXPR)
3509 /* A pointer to member-function can be formed only by saying
3511 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3512 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3514 if (TREE_CODE (xarg) != OFFSET_REF)
3516 error ("invalid use of '%E' to form a pointer-to-member-function. Use a qualified-id.",
3518 return error_mark_node;
3522 error ("parenthesis around '%E' cannot be used to form a pointer-to-member-function",
3524 PTRMEM_OK_P (xarg) = 1;
3528 if (TREE_CODE (xarg) == OFFSET_REF)
3530 ptrmem = PTRMEM_OK_P (xarg);
3532 if (!ptrmem && !flag_ms_extensions
3533 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3535 /* A single non-static member, make sure we don't allow a
3536 pointer-to-member. */
3537 xarg = build (OFFSET_REF, TREE_TYPE (xarg),
3538 TREE_OPERAND (xarg, 0),
3539 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3540 PTRMEM_OK_P (xarg) = ptrmem;
3543 else if (TREE_CODE (xarg) == TARGET_EXPR)
3544 warning ("taking address of temporary");
3545 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3546 if (TREE_CODE (exp) == ADDR_EXPR)
3547 PTRMEM_OK_P (exp) = ptrmem;
3550 if (processing_template_decl && exp != error_mark_node)
3551 return build_min_non_dep (code, exp, orig_expr,
3552 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3556 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3557 constants, where a null value is represented by an INTEGER_CST of
3561 cp_truthvalue_conversion (tree expr)
3563 tree type = TREE_TYPE (expr);
3564 if (TYPE_PTRMEM_P (type))
3565 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3567 return c_common_truthvalue_conversion (expr);
3570 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3573 condition_conversion (tree expr)
3576 if (processing_template_decl)
3578 t = perform_implicit_conversion (boolean_type_node, expr);
3579 t = fold (build1 (CLEANUP_POINT_EXPR, boolean_type_node, t));
3583 /* Return an ADDR_EXPR giving the address of T. This function
3584 attempts no optimizations or simplifications; it is a low-level
3588 build_address (tree t)
3592 if (error_operand_p (t) || !cxx_mark_addressable (t))
3593 return error_mark_node;
3595 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3597 TREE_CONSTANT (addr) = 1;
3602 /* Return a NOP_EXPR converting EXPR to TYPE. */
3605 build_nop (tree type, tree expr)
3609 if (type == error_mark_node || error_operand_p (expr))
3612 nop = build1 (NOP_EXPR, type, expr);
3613 if (TREE_CONSTANT (expr))
3614 TREE_CONSTANT (nop) = 1;
3619 /* C++: Must handle pointers to members.
3621 Perhaps type instantiation should be extended to handle conversion
3622 from aggregates to types we don't yet know we want? (Or are those
3623 cases typically errors which should be reported?)
3625 NOCONVERT nonzero suppresses the default promotions
3626 (such as from short to int). */
3629 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3631 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3632 register tree arg = xarg;
3633 register tree argtype = 0;
3634 const char *errstring = NULL;
3637 if (arg == error_mark_node)
3638 return error_mark_node;
3643 /* This is used for unary plus, because a CONVERT_EXPR
3644 is enough to prevent anybody from looking inside for
3645 associativity, but won't generate any code. */
3646 if (!(arg = build_expr_type_conversion
3647 (WANT_ARITH | WANT_ENUM | WANT_POINTER, arg, true)))
3648 errstring = "wrong type argument to unary plus";
3652 arg = default_conversion (arg);
3653 arg = build1 (NON_LVALUE_EXPR, TREE_TYPE (arg), arg);
3654 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3659 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3660 errstring = "wrong type argument to unary minus";
3661 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3662 arg = perform_integral_promotions (arg);
3666 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3670 arg = default_conversion (arg);
3672 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
3674 errstring = "wrong type argument to bit-complement";
3675 else if (!noconvert)
3676 arg = perform_integral_promotions (arg);
3680 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3681 errstring = "wrong type argument to abs";
3682 else if (!noconvert)
3683 arg = default_conversion (arg);
3687 /* Conjugating a real value is a no-op, but allow it anyway. */
3688 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3689 errstring = "wrong type argument to conjugation";
3690 else if (!noconvert)
3691 arg = default_conversion (arg);
3694 case TRUTH_NOT_EXPR:
3695 arg = perform_implicit_conversion (boolean_type_node, arg);
3696 val = invert_truthvalue (arg);
3697 if (arg != error_mark_node)
3699 errstring = "in argument to unary !";
3706 if (TREE_CODE (arg) == COMPLEX_CST)
3707 return TREE_REALPART (arg);
3708 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3709 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3714 if (TREE_CODE (arg) == COMPLEX_CST)
3715 return TREE_IMAGPART (arg);
3716 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3717 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3719 return cp_convert (TREE_TYPE (arg), integer_zero_node);
3721 case PREINCREMENT_EXPR:
3722 case POSTINCREMENT_EXPR:
3723 case PREDECREMENT_EXPR:
3724 case POSTDECREMENT_EXPR:
3725 /* Handle complex lvalues (when permitted)
3726 by reduction to simpler cases. */
3728 val = unary_complex_lvalue (code, arg);
3732 /* Increment or decrement the real part of the value,
3733 and don't change the imaginary part. */
3734 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3738 arg = stabilize_reference (arg);
3739 real = build_unary_op (REALPART_EXPR, arg, 1);
3740 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
3741 return build (COMPLEX_EXPR, TREE_TYPE (arg),
3742 build_unary_op (code, real, 1), imag);
3745 /* Report invalid types. */
3747 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
3750 if (code == PREINCREMENT_EXPR)
3751 errstring ="no pre-increment operator for type";
3752 else if (code == POSTINCREMENT_EXPR)
3753 errstring ="no post-increment operator for type";
3754 else if (code == PREDECREMENT_EXPR)
3755 errstring ="no pre-decrement operator for type";
3757 errstring ="no post-decrement operator for type";
3761 /* Report something read-only. */
3763 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
3764 || TREE_READONLY (arg))
3765 readonly_error (arg, ((code == PREINCREMENT_EXPR
3766 || code == POSTINCREMENT_EXPR)
3767 ? "increment" : "decrement"),
3772 tree result_type = TREE_TYPE (arg);
3774 arg = get_unwidened (arg, 0);
3775 argtype = TREE_TYPE (arg);
3777 /* ARM $5.2.5 last annotation says this should be forbidden. */
3778 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
3779 pedwarn ("ISO C++ forbids %sing an enum",
3780 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3781 ? "increment" : "decrement");
3783 /* Compute the increment. */
3785 if (TREE_CODE (argtype) == POINTER_TYPE)
3787 tree type = complete_type (TREE_TYPE (argtype));
3789 if (!COMPLETE_OR_VOID_TYPE_P (type))
3790 error ("cannot %s a pointer to incomplete type `%T'",
3791 ((code == PREINCREMENT_EXPR
3792 || code == POSTINCREMENT_EXPR)
3793 ? "increment" : "decrement"), TREE_TYPE (argtype));
3794 else if ((pedantic || warn_pointer_arith)
3795 && !TYPE_PTROB_P (argtype))
3796 pedwarn ("ISO C++ forbids %sing a pointer of type `%T'",
3797 ((code == PREINCREMENT_EXPR
3798 || code == POSTINCREMENT_EXPR)
3799 ? "increment" : "decrement"), argtype);
3800 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
3803 inc = integer_one_node;
3805 inc = cp_convert (argtype, inc);
3807 /* Handle incrementing a cast-expression. */
3809 switch (TREE_CODE (arg))
3814 case FIX_TRUNC_EXPR:
3815 case FIX_FLOOR_EXPR:
3816 case FIX_ROUND_EXPR:
3819 tree incremented, modify, value, compound;
3820 if (! lvalue_p (arg) && pedantic)
3821 pedwarn ("cast to non-reference type used as lvalue");
3822 arg = stabilize_reference (arg);
3823 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
3826 value = save_expr (arg);
3827 incremented = build (((code == PREINCREMENT_EXPR
3828 || code == POSTINCREMENT_EXPR)
3829 ? PLUS_EXPR : MINUS_EXPR),
3830 argtype, value, inc);
3832 modify = build_modify_expr (arg, NOP_EXPR, incremented);
3833 compound = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
3835 /* Eliminate warning about unused result of + or -. */
3836 TREE_NO_UNUSED_WARNING (compound) = 1;
3844 /* Complain about anything else that is not a true lvalue. */
3845 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
3846 || code == POSTINCREMENT_EXPR)
3847 ? "increment" : "decrement")))
3848 return error_mark_node;
3850 /* Forbid using -- on `bool'. */
3851 if (TREE_TYPE (arg) == boolean_type_node)
3853 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
3855 error ("invalid use of `--' on bool variable `%D'", arg);
3856 return error_mark_node;
3858 val = boolean_increment (code, arg);
3861 val = build (code, TREE_TYPE (arg), arg, inc);
3863 TREE_SIDE_EFFECTS (val) = 1;
3864 return cp_convert (result_type, val);
3868 /* Note that this operation never does default_conversion
3869 regardless of NOCONVERT. */
3871 argtype = lvalue_type (arg);
3873 if (TREE_CODE (arg) == OFFSET_REF)
3876 if (TREE_CODE (argtype) == REFERENCE_TYPE)
3880 build_pointer_type (TREE_TYPE (argtype)), arg);
3881 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3884 else if (pedantic && DECL_MAIN_P (arg))
3886 pedwarn ("ISO C++ forbids taking address of function `::main'");
3888 /* Let &* cancel out to simplify resulting code. */
3889 if (TREE_CODE (arg) == INDIRECT_REF)
3891 /* We don't need to have `current_class_ptr' wrapped in a
3892 NON_LVALUE_EXPR node. */
3893 if (arg == current_class_ref)
3894 return current_class_ptr;
3896 arg = TREE_OPERAND (arg, 0);
3897 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
3901 build_pointer_type (TREE_TYPE (TREE_TYPE (arg))), arg);
3902 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3904 else if (lvalue_p (arg))
3905 /* Don't let this be an lvalue. */
3906 return non_lvalue (arg);
3910 /* For &x[y], return x+y */
3911 if (TREE_CODE (arg) == ARRAY_REF)
3913 if (!cxx_mark_addressable (TREE_OPERAND (arg, 0)))
3914 return error_mark_node;
3915 return cp_build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
3916 TREE_OPERAND (arg, 1));
3919 /* Uninstantiated types are all functions. Taking the
3920 address of a function is a no-op, so just return the
3923 if (TREE_CODE (arg) == IDENTIFIER_NODE
3924 && IDENTIFIER_OPNAME_P (arg))
3927 /* We don't know the type yet, so just work around the problem.
3928 We know that this will resolve to an lvalue. */
3929 return build1 (ADDR_EXPR, unknown_type_node, arg);
3932 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
3933 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
3935 /* They're trying to take the address of a unique non-static
3936 member function. This is ill-formed (except in MS-land),
3937 but let's try to DTRT.
3938 Note: We only handle unique functions here because we don't
3939 want to complain if there's a static overload; non-unique
3940 cases will be handled by instantiate_type. But we need to
3941 handle this case here to allow casts on the resulting PMF.
3942 We could defer this in non-MS mode, but it's easier to give
3943 a useful error here. */
3945 /* Inside constant member functions, the `this' pointer
3946 contains an extra const qualifier. TYPE_MAIN_VARIANT
3947 is used here to remove this const from the diagnostics
3948 and the created OFFSET_REF. */
3949 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
3950 tree name = DECL_NAME (get_first_fn (TREE_OPERAND (arg, 1)));
3952 if (! flag_ms_extensions)
3954 if (current_class_type
3955 && TREE_OPERAND (arg, 0) == current_class_ref)
3956 /* An expression like &memfn. */
3957 pedwarn ("ISO C++ forbids taking the address of an unqualified"
3958 " or parenthesized non-static member function to form"
3959 " a pointer to member function. Say `&%T::%D'",
3962 pedwarn ("ISO C++ forbids taking the address of a bound member"
3963 " function to form a pointer to member function."
3967 arg = build_offset_ref (base, name, /*address_p=*/true);
3971 if (type_unknown_p (arg))
3972 return build1 (ADDR_EXPR, unknown_type_node, arg);
3974 /* Handle complex lvalues (when permitted)
3975 by reduction to simpler cases. */
3976 val = unary_complex_lvalue (code, arg);
3980 switch (TREE_CODE (arg))
3985 case FIX_TRUNC_EXPR:
3986 case FIX_FLOOR_EXPR:
3987 case FIX_ROUND_EXPR:
3989 if (! lvalue_p (arg) && pedantic)
3990 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
3997 /* Allow the address of a constructor if all the elements
3999 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_HAS_CONSTRUCTOR (arg)
4000 && TREE_CONSTANT (arg))
4002 /* Anything not already handled and not a true memory reference
4004 else if (TREE_CODE (argtype) != FUNCTION_TYPE
4005 && TREE_CODE (argtype) != METHOD_TYPE
4006 && !lvalue_or_else (arg, "unary `&'"))
4007 return error_mark_node;
4009 if (argtype != error_mark_node)
4010 argtype = build_pointer_type (argtype);
4015 if (TREE_CODE (arg) != COMPONENT_REF)
4016 addr = build_address (arg);
4017 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4019 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4021 /* We can only get here with a single static member
4023 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL
4024 && DECL_STATIC_FUNCTION_P (fn),
4027 addr = build_address (fn);
4028 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4029 /* Do not lose object's side effects. */
4030 addr = build (COMPOUND_EXPR, TREE_TYPE (addr),
4031 TREE_OPERAND (arg, 0), addr);
4033 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4035 error ("attempt to take address of bit-field structure member `%D'",
4036 TREE_OPERAND (arg, 1));
4037 return error_mark_node;
4041 /* Unfortunately we cannot just build an address
4042 expression here, because we would not handle
4043 address-constant-expressions or offsetof correctly. */
4044 tree field = TREE_OPERAND (arg, 1);
4045 tree rval = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
4046 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (rval)),
4047 decl_type_context (field),
4050 rval = build_base_path (PLUS_EXPR, rval, binfo, 1);
4051 rval = build_nop (argtype, rval);
4052 addr = fold (build (PLUS_EXPR, argtype, rval,
4053 cp_convert (argtype, byte_position (field))));
4056 if (TREE_CODE (argtype) == POINTER_TYPE
4057 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4059 build_ptrmemfunc_type (argtype);
4060 addr = build_ptrmemfunc (argtype, addr, 0);
4073 argtype = TREE_TYPE (arg);
4074 return fold (build1 (code, argtype, arg));
4077 error ("%s", errstring);
4078 return error_mark_node;
4081 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4082 for certain kinds of expressions which are not really lvalues
4083 but which we can accept as lvalues.
4085 If ARG is not a kind of expression we can handle, return zero. */
4088 unary_complex_lvalue (enum tree_code code, tree arg)
4090 /* Handle (a, b) used as an "lvalue". */
4091 if (TREE_CODE (arg) == COMPOUND_EXPR)
4093 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4094 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
4095 TREE_OPERAND (arg, 0), real_result);
4098 /* Handle (a ? b : c) used as an "lvalue". */
4099 if (TREE_CODE (arg) == COND_EXPR
4100 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4101 return rationalize_conditional_expr (code, arg);
4103 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4104 if (TREE_CODE (arg) == MODIFY_EXPR
4105 || TREE_CODE (arg) == PREINCREMENT_EXPR
4106 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4108 tree lvalue = TREE_OPERAND (arg, 0);
4109 if (TREE_SIDE_EFFECTS (lvalue))
4111 lvalue = stabilize_reference (lvalue);
4112 arg = build (TREE_CODE (arg), TREE_TYPE (arg),
4113 lvalue, TREE_OPERAND (arg, 1));
4115 return unary_complex_lvalue
4116 (code, build (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4119 if (code != ADDR_EXPR)
4122 /* Handle (a = b) used as an "lvalue" for `&'. */
4123 if (TREE_CODE (arg) == MODIFY_EXPR
4124 || TREE_CODE (arg) == INIT_EXPR)
4126 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4127 arg = build (COMPOUND_EXPR, TREE_TYPE (real_result), arg, real_result);
4128 TREE_NO_UNUSED_WARNING (arg) = 1;
4132 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4133 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4134 || TREE_CODE (arg) == OFFSET_REF)
4138 my_friendly_assert (TREE_CODE (arg) != SCOPE_REF, 313);
4140 if (TREE_CODE (arg) != OFFSET_REF)
4143 t = TREE_OPERAND (arg, 1);
4145 /* Check all this code for right semantics. */
4146 if (TREE_CODE (t) == FUNCTION_DECL)
4148 if (DECL_DESTRUCTOR_P (t))
4149 error ("taking address of destructor");
4150 return build_unary_op (ADDR_EXPR, t, 0);
4152 if (TREE_CODE (t) == VAR_DECL)
4153 return build_unary_op (ADDR_EXPR, t, 0);
4158 if (TREE_OPERAND (arg, 0)
4159 && ! is_dummy_object (TREE_OPERAND (arg, 0))
4160 && TREE_CODE (t) != FIELD_DECL)
4162 error ("taking address of bound pointer-to-member expression");
4163 return error_mark_node;
4165 if (!PTRMEM_OK_P (arg))
4166 return build_unary_op (code, arg, 0);
4168 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4170 error ("cannot create pointer to reference member `%D'", t);
4171 return error_mark_node;
4174 type = build_ptrmem_type (DECL_FIELD_CONTEXT (t), TREE_TYPE (t));
4175 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4181 /* We permit compiler to make function calls returning
4182 objects of aggregate type look like lvalues. */
4186 if (TREE_CODE (targ) == SAVE_EXPR)
4187 targ = TREE_OPERAND (targ, 0);
4189 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4191 if (TREE_CODE (arg) == SAVE_EXPR)
4194 targ = build_cplus_new (TREE_TYPE (arg), arg);
4195 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4198 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4199 return build (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4200 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4203 /* Don't let anything else be handled specially. */
4207 /* Mark EXP saying that we need to be able to take the
4208 address of it; it should not be allocated in a register.
4209 Value is true if successful.
4211 C++: we do not allow `current_class_ptr' to be addressable. */
4214 cxx_mark_addressable (tree exp)
4216 register tree x = exp;
4219 switch (TREE_CODE (x))
4226 x = TREE_OPERAND (x, 0);
4230 if (x == current_class_ptr)
4232 error ("cannot take the address of `this', which is an rvalue expression");
4233 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later */
4239 /* Caller should not be trying to mark initialized
4240 constant fields addressable. */
4241 my_friendly_assert (DECL_LANG_SPECIFIC (x) == 0
4242 || DECL_IN_AGGR_P (x) == 0
4244 || DECL_EXTERNAL (x), 314);
4249 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4250 && !DECL_ARTIFICIAL (x) && extra_warnings)
4251 warning ("address requested for `%D', which is declared `register'",
4253 TREE_ADDRESSABLE (x) = 1;
4254 put_var_into_stack (x, /*rescan=*/true);
4258 TREE_ADDRESSABLE (x) = 1;
4259 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
4263 TREE_ADDRESSABLE (x) = 1;
4267 TREE_ADDRESSABLE (x) = 1;
4268 cxx_mark_addressable (TREE_OPERAND (x, 0));
4276 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4279 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4281 tree orig_ifexp = ifexp;
4282 tree orig_op1 = op1;
4283 tree orig_op2 = op2;
4286 if (processing_template_decl)
4288 /* The standard says that the expression is type-dependent if
4289 IFEXP is type-dependent, even though the eventual type of the
4290 expression doesn't dependent on IFEXP. */
4291 if (type_dependent_expression_p (ifexp)
4292 /* As a GNU extension, the middle operand may be omitted. */
4293 || (op1 && type_dependent_expression_p (op1))
4294 || type_dependent_expression_p (op2))
4295 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4296 ifexp = build_non_dependent_expr (ifexp);
4298 op1 = build_non_dependent_expr (op1);
4299 op2 = build_non_dependent_expr (op2);
4302 expr = build_conditional_expr (ifexp, op1, op2);
4303 if (processing_template_decl && expr != error_mark_node)
4304 return build_min_non_dep (COND_EXPR, expr,
4305 orig_ifexp, orig_op1, orig_op2);
4309 /* Given a list of expressions, return a compound expression
4310 that performs them all and returns the value of the last of them. */
4312 tree build_x_compound_expr_from_list (tree list, const char *msg)
4314 tree expr = TREE_VALUE (list);
4316 if (TREE_CHAIN (list))
4319 pedwarn ("%s expression list treated as compound expression", msg);
4321 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4322 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4328 /* Handle overloading of the ',' operator when needed. */
4331 build_x_compound_expr (tree op1, tree op2)
4334 tree orig_op1 = op1;
4335 tree orig_op2 = op2;
4337 if (processing_template_decl)
4339 if (type_dependent_expression_p (op1)
4340 || type_dependent_expression_p (op2))
4341 return build_min_nt (COMPOUND_EXPR, op1, op2);
4342 op1 = build_non_dependent_expr (op1);
4343 op2 = build_non_dependent_expr (op2);
4346 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE);
4348 result = build_compound_expr (op1, op2);
4350 if (processing_template_decl && result != error_mark_node)
4351 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4356 /* Build a compound expression. */
4359 build_compound_expr (tree lhs, tree rhs)
4361 lhs = decl_constant_value (lhs);
4362 lhs = convert_to_void (lhs, "left-hand operand of comma");
4364 if (lhs == error_mark_node || rhs == error_mark_node)
4365 return error_mark_node;
4367 if (TREE_CODE (rhs) == TARGET_EXPR)
4369 /* If the rhs is a TARGET_EXPR, then build the compound
4370 expression inside the target_expr's initializer. This
4371 helps the compiler to eliminate unnecessary temporaries. */
4372 tree init = TREE_OPERAND (rhs, 1);
4374 init = build (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4375 TREE_OPERAND (rhs, 1) = init;
4380 return build (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4383 /* Issue an error message if casting from SRC_TYPE to DEST_TYPE casts
4384 away constness. DESCRIPTION explains what operation is taking
4388 check_for_casting_away_constness (tree src_type, tree dest_type,
4389 const char *description)
4391 if (casts_away_constness (src_type, dest_type))
4392 error ("%s from type `%T' to type `%T' casts away constness",
4393 description, src_type, dest_type);
4396 /* Return an expression representing static_cast<TYPE>(EXPR). */
4399 build_static_cast (tree type, tree expr)
4404 if (type == error_mark_node || expr == error_mark_node)
4405 return error_mark_node;
4407 if (processing_template_decl)
4409 expr = build_min (STATIC_CAST_EXPR, type, expr);
4410 /* We don't know if it will or will not have side effects. */
4411 TREE_SIDE_EFFECTS (expr) = 1;
4415 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4416 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4417 if (TREE_CODE (type) != REFERENCE_TYPE
4418 && TREE_CODE (expr) == NOP_EXPR
4419 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4420 expr = TREE_OPERAND (expr, 0);
4422 intype = TREE_TYPE (expr);
4424 /* [expr.static.cast]
4426 An lvalue of type "cv1 B", where B is a class type, can be cast
4427 to type "reference to cv2 D", where D is a class derived (clause
4428 _class.derived_) from B, if a valid standard conversion from
4429 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4430 same cv-qualification as, or greater cv-qualification than, cv1,
4431 and B is not a virtual base class of D. */
4432 /* We check this case before checking the validity of "TYPE t =
4433 EXPR;" below because for this case:
4436 struct D : public B { D(const B&); };
4438 void f() { static_cast<const D&>(b); }
4440 we want to avoid constructing a new D. The standard is not
4441 completely clear about this issue, but our interpretation is
4442 consistent with other compilers. */
4443 if (TREE_CODE (type) == REFERENCE_TYPE
4444 && CLASS_TYPE_P (TREE_TYPE (type))
4445 && CLASS_TYPE_P (intype)
4446 && real_lvalue_p (expr)
4447 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4448 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4449 build_pointer_type (TYPE_MAIN_VARIANT
4450 (TREE_TYPE (type))))
4451 && at_least_as_qualified_p (TREE_TYPE (type), intype))
4453 /* There is a standard conversion from "D*" to "B*" even if "B"
4454 is ambiguous or inaccessible. Therefore, we ask lookup_base
4455 to check these conditions. */
4456 tree base = lookup_base (TREE_TYPE (type), intype, ba_check, NULL);
4458 /* Convert from "B*" to "D*". This function will check that "B"
4459 is not a virtual base of "D". */
4460 expr = build_base_path (MINUS_EXPR, build_address (expr),
4461 base, /*nonnull=*/false);
4462 /* Convert the pointer to a reference -- but then remember that
4463 there are no expressions with reference type in C++. */
4464 return convert_from_reference (build_nop (type, expr));
4467 /* [expr.static.cast]
4469 An expression e can be explicitly converted to a type T using a
4470 static_cast of the form static_cast<T>(e) if the declaration T
4471 t(e);" is well-formed, for some invented temporary variable
4473 result = perform_direct_initialization_if_possible (type, expr);
4475 return convert_from_reference (result);
4477 /* [expr.static.cast]
4479 Any expression can be explicitly converted to type cv void. */
4480 if (TREE_CODE (type) == VOID_TYPE)
4481 return convert_to_void (expr, /*implicit=*/NULL);
4483 /* [expr.static.cast]
4485 The inverse of any standard conversion sequence (clause _conv_),
4486 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4487 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4488 (_conv.bool_) conversions, can be performed explicitly using
4489 static_cast subject to the restriction that the explicit
4490 conversion does not cast away constness (_expr.const.cast_), and
4491 the following additional rules for specific cases: */
4492 /* For reference, the conversions not excluded are: integral
4493 promotions, floating point promotion, integral conversions,
4494 floating point conversions, floating-integral conversions,
4495 pointer conversions, and pointer to member conversions. */
4496 if ((ARITHMETIC_TYPE_P (type) && ARITHMETIC_TYPE_P (intype))
4499 A value of integral _or enumeration_ type can be explicitly
4500 converted to an enumeration type. */
4501 || (INTEGRAL_OR_ENUMERATION_TYPE_P (type)
4502 && INTEGRAL_OR_ENUMERATION_TYPE_P (intype)))
4503 /* Really, build_c_cast should defer to this function rather
4504 than the other way around. */
4505 return build_c_cast (type, expr);
4507 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4508 && CLASS_TYPE_P (TREE_TYPE (type))
4509 && CLASS_TYPE_P (TREE_TYPE (intype))
4510 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4511 (TREE_TYPE (intype))),
4512 build_pointer_type (TYPE_MAIN_VARIANT
4513 (TREE_TYPE (type)))))
4517 check_for_casting_away_constness (intype, type, "static_cast");
4518 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype), ba_check,
4520 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4523 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4524 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4531 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4532 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4534 if (TYPE_PTRMEM_P (type))
4536 t1 = (build_ptrmem_type
4538 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4539 t2 = (build_ptrmem_type
4541 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4548 if (can_convert (t1, t2))
4550 check_for_casting_away_constness (intype, type, "static_cast");
4551 if (TYPE_PTRMEM_P (type))
4555 if (TREE_CODE (expr) == PTRMEM_CST)
4556 expr = cplus_expand_constant (expr);
4557 delta = get_delta_difference (c1, c2, /*force=*/1);
4558 if (!integer_zerop (delta))
4559 expr = cp_build_binary_op (PLUS_EXPR,
4560 build_nop (ptrdiff_type_node, expr),
4562 return build_nop (type, expr);
4565 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4570 /* [expr.static.cast]
4572 An rvalue of type "pointer to cv void" can be explicitly
4573 converted to a pointer to object type. A value of type pointer
4574 to object converted to "pointer to cv void" and back to the
4575 original pointer type will have its original value. */
4576 if (TREE_CODE (intype) == POINTER_TYPE
4577 && VOID_TYPE_P (TREE_TYPE (intype))
4578 && TYPE_PTROB_P (type))
4580 check_for_casting_away_constness (intype, type, "static_cast");
4581 return build_nop (type, expr);
4584 error ("invalid static_cast from type `%T' to type `%T'", intype, type);
4585 return error_mark_node;
4589 build_reinterpret_cast (tree type, tree expr)
4593 if (type == error_mark_node || expr == error_mark_node)
4594 return error_mark_node;
4596 if (processing_template_decl)
4598 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
4600 if (!TREE_SIDE_EFFECTS (t)
4601 && type_dependent_expression_p (expr))
4602 /* There might turn out to be side effects inside expr. */
4603 TREE_SIDE_EFFECTS (t) = 1;
4607 if (TREE_CODE (type) != REFERENCE_TYPE)
4609 expr = decay_conversion (expr);
4611 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4612 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4613 if (TREE_CODE (expr) == NOP_EXPR
4614 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4615 expr = TREE_OPERAND (expr, 0);
4618 intype = TREE_TYPE (expr);
4620 if (TREE_CODE (type) == REFERENCE_TYPE)
4622 if (! real_lvalue_p (expr))
4624 error ("invalid reinterpret_cast of an rvalue expression of type `%T' to type `%T'", intype, type);
4625 return error_mark_node;
4627 expr = build_unary_op (ADDR_EXPR, expr, 0);
4628 if (expr != error_mark_node)
4629 expr = build_reinterpret_cast
4630 (build_pointer_type (TREE_TYPE (type)), expr);
4631 if (expr != error_mark_node)
4632 expr = build_indirect_ref (expr, 0);
4635 else if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4636 return build_static_cast (type, expr);
4638 if (TYPE_PTR_P (type) && (TREE_CODE (intype) == INTEGER_TYPE
4639 || TREE_CODE (intype) == ENUMERAL_TYPE))
4641 else if (TREE_CODE (type) == INTEGER_TYPE && TYPE_PTR_P (intype))
4643 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
4644 pedwarn ("reinterpret_cast from `%T' to `%T' loses precision",
4647 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
4648 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4650 expr = decl_constant_value (expr);
4651 return fold (build1 (NOP_EXPR, type, expr));
4653 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4654 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
4656 check_for_casting_away_constness (intype, type, "reinterpret_cast");
4657 expr = decl_constant_value (expr);
4658 return fold (build1 (NOP_EXPR, type, expr));
4660 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
4661 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
4663 pedwarn ("ISO C++ forbids casting between pointer-to-function and pointer-to-object");
4664 expr = decl_constant_value (expr);
4665 return fold (build1 (NOP_EXPR, type, expr));
4669 error ("invalid reinterpret_cast from type `%T' to type `%T'",
4671 return error_mark_node;
4674 return cp_convert (type, expr);
4678 build_const_cast (tree type, tree expr)
4682 if (type == error_mark_node || expr == error_mark_node)
4683 return error_mark_node;
4685 if (processing_template_decl)
4687 tree t = build_min (CONST_CAST_EXPR, type, expr);
4689 if (!TREE_SIDE_EFFECTS (t)
4690 && type_dependent_expression_p (expr))
4691 /* There might turn out to be side effects inside expr. */
4692 TREE_SIDE_EFFECTS (t) = 1;
4696 if (!POINTER_TYPE_P (type))
4697 error ("invalid use of const_cast with type `%T', which is not a pointer, reference, nor a pointer-to-data-member type", type);
4698 else if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4700 error ("invalid use of const_cast with type `%T', which is a pointer or reference to a function type", type);
4701 return error_mark_node;
4704 if (TREE_CODE (type) != REFERENCE_TYPE)
4706 expr = decay_conversion (expr);
4708 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4709 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4710 if (TREE_CODE (expr) == NOP_EXPR
4711 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4712 expr = TREE_OPERAND (expr, 0);
4715 intype = TREE_TYPE (expr);
4717 if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4718 return build_static_cast (type, expr);
4719 else if (TREE_CODE (type) == REFERENCE_TYPE)
4721 if (! real_lvalue_p (expr))
4723 error ("invalid const_cast of an rvalue of type `%T' to type `%T'", intype, type);
4724 return error_mark_node;
4727 if (comp_ptr_ttypes_const (TREE_TYPE (type), intype))
4729 expr = build_unary_op (ADDR_EXPR, expr, 0);
4730 expr = build1 (NOP_EXPR, type, expr);
4731 return convert_from_reference (expr);
4734 else if (((TREE_CODE (type) == POINTER_TYPE
4735 && TREE_CODE (intype) == POINTER_TYPE)
4736 || (TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype)))
4737 && comp_ptr_ttypes_const (TREE_TYPE (type), TREE_TYPE (intype)))
4738 return cp_convert (type, expr);
4740 error ("invalid const_cast from type `%T' to type `%T'", intype, type);
4741 return error_mark_node;
4744 /* Build an expression representing a cast to type TYPE of expression EXPR.
4746 ALLOW_NONCONVERTING is true if we should allow non-converting constructors
4747 when doing the cast. */
4750 build_c_cast (tree type, tree expr)
4752 register tree value = expr;
4755 if (type == error_mark_node || expr == error_mark_node)
4756 return error_mark_node;
4758 if (processing_template_decl)
4760 tree t = build_min (CAST_EXPR, type,
4761 tree_cons (NULL_TREE, value, NULL_TREE));
4762 /* We don't know if it will or will not have side effects. */
4763 TREE_SIDE_EFFECTS (t) = 1;
4767 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4768 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4769 if (TREE_CODE (type) != REFERENCE_TYPE
4770 && TREE_CODE (value) == NOP_EXPR
4771 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
4772 value = TREE_OPERAND (value, 0);
4774 if (TREE_CODE (type) == ARRAY_TYPE)
4776 /* Allow casting from T1* to T2[] because Cfront allows it.
4777 NIHCL uses it. It is not valid ISO C++ however. */
4778 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
4780 pedwarn ("ISO C++ forbids casting to an array type `%T'", type);
4781 type = build_pointer_type (TREE_TYPE (type));
4785 error ("ISO C++ forbids casting to an array type `%T'", type);
4786 return error_mark_node;
4790 if (TREE_CODE (type) == FUNCTION_TYPE
4791 || TREE_CODE (type) == METHOD_TYPE)
4793 error ("invalid cast to function type `%T'", type);
4794 return error_mark_node;
4797 if (TREE_CODE (type) == VOID_TYPE)
4799 /* Conversion to void does not cause any of the normal function to
4800 * pointer, array to pointer and lvalue to rvalue decays. */
4802 value = convert_to_void (value, /*implicit=*/NULL);
4806 if (!complete_type_or_else (type, NULL_TREE))
4807 return error_mark_node;
4809 /* Convert functions and arrays to pointers and
4810 convert references to their expanded types,
4811 but don't convert any other types. If, however, we are
4812 casting to a class type, there's no reason to do this: the
4813 cast will only succeed if there is a converting constructor,
4814 and the default conversions will be done at that point. In
4815 fact, doing the default conversion here is actually harmful
4819 struct S { S(const A&); };
4821 since we don't want the array-to-pointer conversion done. */
4822 if (!IS_AGGR_TYPE (type))
4824 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
4825 || (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE
4826 /* Don't do the default conversion on a ->* expression. */
4827 && ! (TREE_CODE (type) == POINTER_TYPE
4828 && bound_pmf_p (value)))
4829 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
4830 || TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4831 value = decay_conversion (value);
4833 else if (TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4834 /* However, even for class types, we still need to strip away
4835 the reference type, since the call to convert_force below
4836 does not expect the input expression to be of reference
4838 value = convert_from_reference (value);
4840 otype = TREE_TYPE (value);
4842 /* Optionally warn about potentially worrisome casts. */
4845 && TREE_CODE (type) == POINTER_TYPE
4846 && TREE_CODE (otype) == POINTER_TYPE
4847 && !at_least_as_qualified_p (TREE_TYPE (type),
4849 warning ("cast from `%T' to `%T' discards qualifiers from pointer target type",
4852 if (TREE_CODE (type) == INTEGER_TYPE
4853 && TYPE_PTR_P (otype)
4854 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
4855 warning ("cast from pointer to integer of different size");
4857 if (TYPE_PTR_P (type)
4858 && TREE_CODE (otype) == INTEGER_TYPE
4859 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
4860 /* Don't warn about converting any constant. */
4861 && !TREE_CONSTANT (value))
4862 warning ("cast to pointer from integer of different size");
4864 if (TREE_CODE (type) == REFERENCE_TYPE)
4865 value = (convert_from_reference
4866 (convert_to_reference (type, value, CONV_C_CAST,
4867 LOOKUP_COMPLAIN, NULL_TREE)));
4872 value = decl_constant_value (value);
4875 value = convert_force (type, value, CONV_C_CAST);
4877 /* Ignore any integer overflow caused by the cast. */
4878 if (TREE_CODE (value) == INTEGER_CST)
4880 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
4881 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
4885 /* Warn about possible alignment problems. Do this here when we will have
4886 instantiated any necessary template types. */
4887 if (STRICT_ALIGNMENT && warn_cast_align
4888 && TREE_CODE (type) == POINTER_TYPE
4889 && TREE_CODE (otype) == POINTER_TYPE
4890 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
4891 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
4892 && COMPLETE_TYPE_P (TREE_TYPE (otype))
4893 && COMPLETE_TYPE_P (TREE_TYPE (type))
4894 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
4895 warning ("cast from `%T' to `%T' increases required alignment of target type",
4898 /* Always produce some operator for an explicit cast,
4899 so we can tell (for -pedantic) that the cast is no lvalue. */
4900 if (TREE_CODE (type) != REFERENCE_TYPE && value == expr
4901 && real_lvalue_p (value))
4902 value = non_lvalue (value);
4907 /* Build an assignment expression of lvalue LHS from value RHS.
4908 MODIFYCODE is the code for a binary operator that we use
4909 to combine the old value of LHS with RHS to get the new value.
4910 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
4912 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
4915 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
4917 register tree result;
4919 tree lhstype = TREE_TYPE (lhs);
4920 tree olhstype = lhstype;
4923 /* Avoid duplicate error messages from operands that had errors. */
4924 if (lhs == error_mark_node || rhs == error_mark_node)
4925 return error_mark_node;
4927 /* Handle control structure constructs used as "lvalues". */
4928 switch (TREE_CODE (lhs))
4930 /* Handle --foo = 5; as these are valid constructs in C++ */
4931 case PREDECREMENT_EXPR:
4932 case PREINCREMENT_EXPR:
4933 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4934 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4935 stabilize_reference (TREE_OPERAND (lhs, 0)),
4936 TREE_OPERAND (lhs, 1));
4937 return build (COMPOUND_EXPR, lhstype,
4939 build_modify_expr (TREE_OPERAND (lhs, 0),
4942 /* Handle (a, b) used as an "lvalue". */
4944 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
4946 if (newrhs == error_mark_node)
4947 return error_mark_node;
4948 return build (COMPOUND_EXPR, lhstype,
4949 TREE_OPERAND (lhs, 0), newrhs);
4952 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4953 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4954 stabilize_reference (TREE_OPERAND (lhs, 0)),
4955 TREE_OPERAND (lhs, 1));
4956 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
4957 if (newrhs == error_mark_node)
4958 return error_mark_node;
4959 return build (COMPOUND_EXPR, lhstype, lhs, newrhs);
4961 /* Handle (a ? b : c) used as an "lvalue". */
4964 /* Produce (a ? (b = rhs) : (c = rhs))
4965 except that the RHS goes through a save-expr
4966 so the code to compute it is only emitted once. */
4968 tree preeval = NULL_TREE;
4970 rhs = stabilize_expr (rhs, &preeval);
4972 /* Check this here to avoid odd errors when trying to convert
4973 a throw to the type of the COND_EXPR. */
4974 if (!lvalue_or_else (lhs, "assignment"))
4975 return error_mark_node;
4977 cond = build_conditional_expr
4978 (TREE_OPERAND (lhs, 0),
4979 build_modify_expr (cp_convert (TREE_TYPE (lhs),
4980 TREE_OPERAND (lhs, 1)),
4982 build_modify_expr (cp_convert (TREE_TYPE (lhs),
4983 TREE_OPERAND (lhs, 2)),
4986 if (cond == error_mark_node)
4988 /* Make sure the code to compute the rhs comes out
4989 before the split. */
4990 return build (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
4997 if (modifycode == INIT_EXPR)
4999 if (TREE_CODE (rhs) == CONSTRUCTOR)
5001 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5002 /* Call convert to generate an error; see PR 11063. */
5003 rhs = convert (lhstype, rhs);
5004 result = build (INIT_EXPR, lhstype, lhs, rhs);
5005 TREE_SIDE_EFFECTS (result) = 1;
5008 else if (! IS_AGGR_TYPE (lhstype))
5009 /* Do the default thing */;
5012 result = build_special_member_call (lhs, complete_ctor_identifier,
5013 build_tree_list (NULL_TREE, rhs),
5014 TYPE_BINFO (lhstype),
5016 if (result == NULL_TREE)
5017 return error_mark_node;
5023 if (TREE_CODE (lhstype) == REFERENCE_TYPE)
5025 lhs = convert_from_reference (lhs);
5026 olhstype = lhstype = TREE_TYPE (lhs);
5028 lhs = require_complete_type (lhs);
5029 if (lhs == error_mark_node)
5030 return error_mark_node;
5032 if (modifycode == NOP_EXPR)
5034 /* `operator=' is not an inheritable operator. */
5035 if (! IS_AGGR_TYPE (lhstype))
5036 /* Do the default thing */;
5039 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5040 lhs, rhs, make_node (NOP_EXPR));
5041 if (result == NULL_TREE)
5042 return error_mark_node;
5049 /* A binary op has been requested. Combine the old LHS
5050 value with the RHS producing the value we should actually
5051 store into the LHS. */
5053 my_friendly_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE),
5055 lhs = stabilize_reference (lhs);
5056 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5057 if (newrhs == error_mark_node)
5059 error (" in evaluation of `%Q(%#T, %#T)'", modifycode,
5060 TREE_TYPE (lhs), TREE_TYPE (rhs));
5061 return error_mark_node;
5064 /* Now it looks like a plain assignment. */
5065 modifycode = NOP_EXPR;
5067 my_friendly_assert (TREE_CODE (lhstype) != REFERENCE_TYPE, 20011220);
5068 my_friendly_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE,
5072 /* Handle a cast used as an "lvalue".
5073 We have already performed any binary operator using the value as cast.
5074 Now convert the result to the cast type of the lhs,
5075 and then true type of the lhs and store it there;
5076 then convert result back to the cast type to be the value
5077 of the assignment. */
5079 switch (TREE_CODE (lhs))
5084 case FIX_TRUNC_EXPR:
5085 case FIX_FLOOR_EXPR:
5086 case FIX_ROUND_EXPR:
5089 tree inner_lhs = TREE_OPERAND (lhs, 0);
5092 if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5093 || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE
5094 || TREE_CODE (TREE_TYPE (newrhs)) == METHOD_TYPE
5095 || TREE_CODE (TREE_TYPE (newrhs)) == OFFSET_TYPE)
5096 newrhs = decay_conversion (newrhs);
5098 /* ISO C++ 5.4/1: The result is an lvalue if T is a reference
5099 type, otherwise the result is an rvalue. */
5100 if (! lvalue_p (lhs))
5101 pedwarn ("ISO C++ forbids cast to non-reference type used as lvalue");
5103 result = build_modify_expr (inner_lhs, NOP_EXPR,
5104 cp_convert (TREE_TYPE (inner_lhs),
5105 cp_convert (lhstype, newrhs)));
5106 if (result == error_mark_node)
5108 return cp_convert (TREE_TYPE (lhs), result);
5115 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
5116 Reject anything strange now. */
5118 if (!lvalue_or_else (lhs, "assignment"))
5119 return error_mark_node;
5121 /* Warn about modifying something that is `const'. Don't warn if
5122 this is initialization. */
5123 if (modifycode != INIT_EXPR
5124 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5125 /* Functions are not modifiable, even though they are
5127 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5128 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5129 /* If it's an aggregate and any field is const, then it is
5130 effectively const. */
5131 || (CLASS_TYPE_P (lhstype)
5132 && C_TYPE_FIELDS_READONLY (lhstype))))
5133 readonly_error (lhs, "assignment", 0);
5135 /* If storing into a structure or union member, it has probably been
5136 given type `int'. Compute the type that would go with the actual
5137 amount of storage the member occupies. */
5139 if (TREE_CODE (lhs) == COMPONENT_REF
5140 && (TREE_CODE (lhstype) == INTEGER_TYPE
5141 || TREE_CODE (lhstype) == REAL_TYPE
5142 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5144 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5146 /* If storing in a field that is in actuality a short or narrower
5147 than one, we must store in the field in its actual type. */
5149 if (lhstype != TREE_TYPE (lhs))
5151 lhs = copy_node (lhs);
5152 TREE_TYPE (lhs) = lhstype;
5156 /* Convert new value to destination type. */
5158 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5162 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5163 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5165 error ("incompatible types in assignment of `%T' to `%T'",
5166 TREE_TYPE (rhs), lhstype);
5167 return error_mark_node;
5170 /* Allow array assignment in compiler-generated code. */
5171 if (! DECL_ARTIFICIAL (current_function_decl))
5172 pedwarn ("ISO C++ forbids assignment of arrays");
5174 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5175 ? 1 + (modifycode != INIT_EXPR): 0;
5176 return build_vec_init (lhs, NULL_TREE, newrhs, from_array);
5179 if (modifycode == INIT_EXPR)
5180 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5181 "initialization", NULL_TREE, 0);
5184 /* Avoid warnings on enum bit fields. */
5185 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5186 && TREE_CODE (lhstype) == INTEGER_TYPE)
5188 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5190 newrhs = convert_force (lhstype, newrhs, 0);
5193 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5195 if (TREE_CODE (newrhs) == CALL_EXPR
5196 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5197 newrhs = build_cplus_new (lhstype, newrhs);
5199 /* Can't initialize directly from a TARGET_EXPR, since that would
5200 cause the lhs to be constructed twice, and possibly result in
5201 accidental self-initialization. So we force the TARGET_EXPR to be
5202 expanded without a target. */
5203 if (TREE_CODE (newrhs) == TARGET_EXPR)
5204 newrhs = build (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5205 TREE_OPERAND (newrhs, 0));
5208 if (newrhs == error_mark_node)
5209 return error_mark_node;
5211 result = build (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5212 lhstype, lhs, newrhs);
5214 TREE_SIDE_EFFECTS (result) = 1;
5216 /* If we got the LHS in a different type for storing in,
5217 convert the result back to the nominal type of LHS
5218 so that the value we return always has the same type
5219 as the LHS argument. */
5221 if (olhstype == TREE_TYPE (result))
5223 /* Avoid warnings converting integral types back into enums
5224 for enum bit fields. */
5225 if (TREE_CODE (TREE_TYPE (result)) == INTEGER_TYPE
5226 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5228 result = build (COMPOUND_EXPR, olhstype, result, olhs);
5229 TREE_NO_UNUSED_WARNING (result) = 1;
5232 return convert_for_assignment (olhstype, result, "assignment",
5237 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5239 if (processing_template_decl)
5240 return build_min_nt (MODOP_EXPR, lhs,
5241 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5243 if (modifycode != NOP_EXPR)
5245 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5246 make_node (modifycode));
5250 return build_modify_expr (lhs, modifycode, rhs);
5254 /* Get difference in deltas for different pointer to member function
5255 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5256 the conversion is invalid, the constant is zero. If FORCE is true,
5257 then allow reverse conversions as well.
5259 Note that the naming of FROM and TO is kind of backwards; the return
5260 value is what we add to a TO in order to get a FROM. They are named
5261 this way because we call this function to find out how to convert from
5262 a pointer to member of FROM to a pointer to member of TO. */
5265 get_delta_difference (tree from, tree to, int force)
5271 binfo = lookup_base (to, from, ba_check, &kind);
5272 if (kind == bk_inaccessible || kind == bk_ambig)
5274 error (" in pointer to member function conversion");
5281 error_not_base_type (from, to);
5282 error (" in pointer to member conversion");
5285 binfo = lookup_base (from, to, ba_check, &kind);
5288 virt_binfo = binfo_from_vbase (binfo);
5291 /* This is a reinterpret cast, we choose to do nothing. */
5292 warning ("pointer to member cast via virtual base `%T'",
5293 BINFO_TYPE (virt_binfo));
5296 return convert_to_integer (ptrdiff_type_node,
5297 size_diffop (size_zero_node,
5298 BINFO_OFFSET (binfo)));
5301 virt_binfo = binfo_from_vbase (binfo);
5303 return convert_to_integer (ptrdiff_type_node, BINFO_OFFSET (binfo));
5305 /* This is a reinterpret cast, we choose to do nothing. */
5307 warning ("pointer to member cast via virtual base `%T'",
5308 BINFO_TYPE (virt_binfo));
5310 error ("pointer to member conversion via virtual base `%T'",
5311 BINFO_TYPE (virt_binfo));
5314 return convert_to_integer(ptrdiff_type_node, integer_zero_node);
5317 /* Return a constructor for the pointer-to-member-function TYPE using
5318 the other components as specified. */
5321 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5327 /* Pull the FIELD_DECLs out of the type. */
5328 pfn_field = TYPE_FIELDS (type);
5329 delta_field = TREE_CHAIN (pfn_field);
5331 /* Make sure DELTA has the type we want. */
5332 delta = convert_and_check (delta_type_node, delta);
5334 /* Finish creating the initializer. */
5335 u = tree_cons (pfn_field, pfn,
5336 build_tree_list (delta_field, delta));
5337 u = build_constructor (type, u);
5338 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) && TREE_CONSTANT (delta);
5339 TREE_STATIC (u) = (TREE_CONSTANT (u)
5340 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5342 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5347 /* Build a constructor for a pointer to member function. It can be
5348 used to initialize global variables, local variable, or used
5349 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5352 If FORCE is nonzero, then force this conversion, even if
5353 we would rather not do it. Usually set when using an explicit
5356 Return error_mark_node, if something goes wrong. */
5359 build_ptrmemfunc (tree type, tree pfn, int force)
5365 if (error_operand_p (pfn))
5366 return error_mark_node;
5368 pfn_type = TREE_TYPE (pfn);
5369 to_type = build_ptrmemfunc_type (type);
5371 /* Handle multiple conversions of pointer to member functions. */
5372 if (TYPE_PTRMEMFUNC_P (pfn_type))
5374 tree delta = NULL_TREE;
5375 tree npfn = NULL_TREE;
5379 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn))
5380 error ("invalid conversion to type `%T' from type `%T'",
5383 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5384 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5387 /* We don't have to do any conversion to convert a
5388 pointer-to-member to its own type. But, we don't want to
5389 just return a PTRMEM_CST if there's an explicit cast; that
5390 cast should make the expression an invalid template argument. */
5391 if (TREE_CODE (pfn) != PTRMEM_CST)
5393 if (same_type_p (to_type, pfn_type))
5395 else if (integer_zerop (n))
5396 return build_reinterpret_cast (to_type, pfn);
5399 if (TREE_SIDE_EFFECTS (pfn))
5400 pfn = save_expr (pfn);
5402 /* Obtain the function pointer and the current DELTA. */
5403 if (TREE_CODE (pfn) == PTRMEM_CST)
5404 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
5407 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
5408 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
5411 /* Just adjust the DELTA field. */
5412 my_friendly_assert (TREE_TYPE (delta) == ptrdiff_type_node, 20030727);
5413 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
5414 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
5415 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
5416 return build_ptrmemfunc1 (to_type, delta, npfn);
5419 /* Handle null pointer to member function conversions. */
5420 if (integer_zerop (pfn))
5422 pfn = build_c_cast (type, integer_zero_node);
5423 return build_ptrmemfunc1 (to_type,
5428 if (type_unknown_p (pfn))
5429 return instantiate_type (type, pfn, tf_error | tf_warning);
5431 fn = TREE_OPERAND (pfn, 0);
5432 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5433 return make_ptrmem_cst (to_type, fn);
5436 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
5439 ??? There is no consistency as to the types returned for the above
5440 values. Some code acts as if its a sizetype and some as if its
5441 integer_type_node. */
5444 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
5446 tree type = TREE_TYPE (cst);
5447 tree fn = PTRMEM_CST_MEMBER (cst);
5448 tree ptr_class, fn_class;
5450 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5452 /* The class that the function belongs to. */
5453 fn_class = DECL_CONTEXT (fn);
5455 /* The class that we're creating a pointer to member of. */
5456 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
5458 /* First, calculate the adjustment to the function's class. */
5459 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0);
5461 if (!DECL_VIRTUAL_P (fn))
5462 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
5465 /* If we're dealing with a virtual function, we have to adjust 'this'
5466 again, to point to the base which provides the vtable entry for
5467 fn; the call will do the opposite adjustment. */
5468 tree orig_class = DECL_CONTEXT (fn);
5469 tree binfo = binfo_or_else (orig_class, fn_class);
5470 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5471 *delta, BINFO_OFFSET (binfo)));
5473 /* We set PFN to the vtable offset at which the function can be
5474 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
5475 case delta is shifted left, and then incremented). */
5476 *pfn = DECL_VINDEX (fn);
5477 *pfn = fold (build (MULT_EXPR, integer_type_node, *pfn,
5478 TYPE_SIZE_UNIT (vtable_entry_type)));
5480 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
5482 case ptrmemfunc_vbit_in_pfn:
5483 *pfn = fold (build (PLUS_EXPR, integer_type_node, *pfn,
5487 case ptrmemfunc_vbit_in_delta:
5488 *delta = fold (build (LSHIFT_EXPR, TREE_TYPE (*delta),
5489 *delta, integer_one_node));
5490 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5491 *delta, integer_one_node));
5498 *pfn = fold (build1 (NOP_EXPR, TYPE_PTRMEMFUNC_FN_TYPE (type),
5503 /* Return an expression for PFN from the pointer-to-member function
5507 pfn_from_ptrmemfunc (tree t)
5509 if (TREE_CODE (t) == PTRMEM_CST)
5514 expand_ptrmemfunc_cst (t, &delta, &pfn);
5519 return build_ptrmemfunc_access_expr (t, pfn_identifier);
5522 /* Expression EXPR is about to be implicitly converted to TYPE. Warn
5523 if this is a potentially dangerous thing to do. Returns a possibly
5527 dubious_conversion_warnings (tree type, tree expr,
5528 const char *errtype, tree fndecl, int parmnum)
5530 type = non_reference (type);
5532 /* Issue warnings about peculiar, but valid, uses of NULL. */
5533 if (ARITHMETIC_TYPE_P (type) && expr == null_node)
5536 warning ("passing NULL used for non-pointer %s %P of `%D'",
5537 errtype, parmnum, fndecl);
5539 warning ("%s to non-pointer type `%T' from NULL", errtype, type);
5542 /* Warn about assigning a floating-point type to an integer type. */
5543 if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE
5544 && TREE_CODE (type) == INTEGER_TYPE)
5547 warning ("passing `%T' for %s %P of `%D'",
5548 TREE_TYPE (expr), errtype, parmnum, fndecl);
5550 warning ("%s to `%T' from `%T'", errtype, type, TREE_TYPE (expr));
5552 /* And warn about assigning a negative value to an unsigned
5554 else if (TREE_UNSIGNED (type) && TREE_CODE (type) != BOOLEAN_TYPE)
5556 if (TREE_CODE (expr) == INTEGER_CST
5557 && TREE_NEGATED_INT (expr))
5560 warning ("passing negative value `%E' for %s %P of `%D'",
5561 expr, errtype, parmnum, fndecl);
5563 warning ("%s of negative value `%E' to `%T'",
5564 errtype, expr, type);
5567 overflow_warning (expr);
5569 if (TREE_CONSTANT (expr))
5575 /* Convert value RHS to type TYPE as preparation for an assignment to
5576 an lvalue of type TYPE. ERRTYPE is a string to use in error
5577 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
5578 are doing the conversion in order to pass the PARMNUMth argument of
5582 convert_for_assignment (tree type, tree rhs,
5583 const char *errtype, tree fndecl, int parmnum)
5585 register tree rhstype;
5586 register enum tree_code coder;
5588 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
5589 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
5590 rhs = TREE_OPERAND (rhs, 0);
5592 rhstype = TREE_TYPE (rhs);
5593 coder = TREE_CODE (rhstype);
5595 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
5596 && ((*targetm.vector_opaque_p) (type)
5597 || (*targetm.vector_opaque_p) (rhstype)))
5598 return convert (type, rhs);
5600 if (rhs == error_mark_node || rhstype == error_mark_node)
5601 return error_mark_node;
5602 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
5603 return error_mark_node;
5605 rhs = dubious_conversion_warnings (type, rhs, errtype, fndecl, parmnum);
5607 /* The RHS of an assignment cannot have void type. */
5608 if (coder == VOID_TYPE)
5610 error ("void value not ignored as it ought to be");
5611 return error_mark_node;
5614 /* Simplify the RHS if possible. */
5615 if (TREE_CODE (rhs) == CONST_DECL)
5616 rhs = DECL_INITIAL (rhs);
5618 /* We do not use decl_constant_value here because of this case:
5620 const char* const s = "s";
5622 The conversion rules for a string literal are more lax than for a
5623 variable; in particular, a string literal can be converted to a
5624 "char *" but the variable "s" cannot be converted in the same
5625 way. If the conversion is allowed, the optimization should be
5626 performed while creating the converted expression. */
5630 The expression is implicitly converted (clause _conv_) to the
5631 cv-unqualified type of the left operand.
5633 We allow bad conversions here because by the time we get to this point
5634 we are committed to doing the conversion. If we end up doing a bad
5635 conversion, convert_like will complain. */
5636 if (!can_convert_arg_bad (type, rhstype, rhs))
5638 /* When -Wno-pmf-conversions is use, we just silently allow
5639 conversions from pointers-to-members to plain pointers. If
5640 the conversion doesn't work, cp_convert will complain. */
5642 && TYPE_PTR_P (type)
5643 && TYPE_PTRMEMFUNC_P (rhstype))
5644 rhs = cp_convert (strip_top_quals (type), rhs);
5647 /* If the right-hand side has unknown type, then it is an
5648 overloaded function. Call instantiate_type to get error
5650 if (rhstype == unknown_type_node)
5651 instantiate_type (type, rhs, tf_error | tf_warning);
5653 error ("cannot convert `%T' to `%T' for argument `%P' to `%D'",
5654 rhstype, type, parmnum, fndecl);
5656 error ("cannot convert `%T' to `%T' in %s", rhstype, type,
5658 return error_mark_node;
5661 return perform_implicit_conversion (strip_top_quals (type), rhs);
5664 /* Convert RHS to be of type TYPE.
5665 If EXP is nonzero, it is the target of the initialization.
5666 ERRTYPE is a string to use in error messages.
5668 Two major differences between the behavior of
5669 `convert_for_assignment' and `convert_for_initialization'
5670 are that references are bashed in the former, while
5671 copied in the latter, and aggregates are assigned in
5672 the former (operator=) while initialized in the
5675 If using constructor make sure no conversion operator exists, if one does
5676 exist, an ambiguity exists.
5678 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
5681 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
5682 const char *errtype, tree fndecl, int parmnum)
5684 register enum tree_code codel = TREE_CODE (type);
5685 register tree rhstype;
5686 register enum tree_code coder;
5688 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5689 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
5690 if (TREE_CODE (rhs) == NOP_EXPR
5691 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
5692 && codel != REFERENCE_TYPE)
5693 rhs = TREE_OPERAND (rhs, 0);
5695 if (rhs == error_mark_node
5696 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
5697 return error_mark_node;
5699 if (TREE_CODE (TREE_TYPE (rhs)) == REFERENCE_TYPE)
5700 rhs = convert_from_reference (rhs);
5702 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
5703 && TREE_CODE (type) != ARRAY_TYPE
5704 && (TREE_CODE (type) != REFERENCE_TYPE
5705 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
5706 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
5707 && (TREE_CODE (type) != REFERENCE_TYPE
5708 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
5709 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
5710 rhs = decay_conversion (rhs);
5712 rhstype = TREE_TYPE (rhs);
5713 coder = TREE_CODE (rhstype);
5715 if (coder == ERROR_MARK)
5716 return error_mark_node;
5718 /* We accept references to incomplete types, so we can
5719 return here before checking if RHS is of complete type. */
5721 if (codel == REFERENCE_TYPE)
5723 /* This should eventually happen in convert_arguments. */
5724 int savew = 0, savee = 0;
5727 savew = warningcount, savee = errorcount;
5728 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
5732 if (warningcount > savew)
5733 cp_warning_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5734 else if (errorcount > savee)
5735 cp_error_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5741 exp = require_complete_type (exp);
5742 if (exp == error_mark_node)
5743 return error_mark_node;
5745 rhstype = non_reference (rhstype);
5747 type = complete_type (type);
5749 if (IS_AGGR_TYPE (type))
5750 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
5752 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
5755 /* Expand an ASM statement with operands, handling output operands
5756 that are not variables or INDIRECT_REFS by transforming such
5757 cases into cases that expand_asm_operands can handle.
5759 Arguments are same as for expand_asm_operands.
5761 We don't do default conversions on all inputs, because it can screw
5762 up operands that are expected to be in memory. */
5765 c_expand_asm_operands (tree string, tree outputs, tree inputs, tree clobbers,
5766 int vol, location_t locus)
5768 int noutputs = list_length (outputs);
5770 /* o[I] is the place that output number I should be written. */
5771 register tree *o = alloca (noutputs * sizeof (tree));
5774 /* Record the contents of OUTPUTS before it is modified. */
5775 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5776 o[i] = TREE_VALUE (tail);
5778 /* Generate the ASM_OPERANDS insn;
5779 store into the TREE_VALUEs of OUTPUTS some trees for
5780 where the values were actually stored. */
5781 expand_asm_operands (string, outputs, inputs, clobbers, vol, locus);
5783 /* Copy all the intermediate outputs into the specified outputs. */
5784 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5786 if (o[i] != TREE_VALUE (tail))
5788 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
5789 const0_rtx, VOIDmode, EXPAND_NORMAL);
5792 /* Restore the original value so that it's correct the next
5793 time we expand this function. */
5794 TREE_VALUE (tail) = o[i];
5796 /* Detect modification of read-only values.
5797 (Otherwise done by build_modify_expr.) */
5800 tree type = TREE_TYPE (o[i]);
5801 if (type != error_mark_node
5802 && (CP_TYPE_CONST_P (type)
5803 || (CLASS_TYPE_P (type) && C_TYPE_FIELDS_READONLY (type))))
5804 readonly_error (o[i], "modification by `asm'", 1);
5808 /* Those MODIFY_EXPRs could do autoincrements. */
5812 /* If RETVAL is the address of, or a reference to, a local variable or
5813 temporary give an appropriate warning. */
5816 maybe_warn_about_returning_address_of_local (tree retval)
5818 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
5819 tree whats_returned = retval;
5823 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
5824 whats_returned = TREE_OPERAND (whats_returned, 1);
5825 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
5826 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
5827 || TREE_CODE (whats_returned) == NOP_EXPR)
5828 whats_returned = TREE_OPERAND (whats_returned, 0);
5833 if (TREE_CODE (whats_returned) != ADDR_EXPR)
5835 whats_returned = TREE_OPERAND (whats_returned, 0);
5837 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5839 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
5840 || TREE_CODE (whats_returned) == TARGET_EXPR)
5842 warning ("returning reference to temporary");
5845 if (TREE_CODE (whats_returned) == VAR_DECL
5846 && DECL_NAME (whats_returned)
5847 && TEMP_NAME_P (DECL_NAME (whats_returned)))
5849 warning ("reference to non-lvalue returned");
5854 if (TREE_CODE (whats_returned) == VAR_DECL
5855 && DECL_NAME (whats_returned)
5856 && DECL_FUNCTION_SCOPE_P (whats_returned)
5857 && !(TREE_STATIC (whats_returned)
5858 || TREE_PUBLIC (whats_returned)))
5860 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5861 cp_warning_at ("reference to local variable `%D' returned",
5864 cp_warning_at ("address of local variable `%D' returned",
5870 /* Check that returning RETVAL from the current function is valid.
5871 Return an expression explicitly showing all conversions required to
5872 change RETVAL into the function return type, and to assign it to
5873 the DECL_RESULT for the function. */
5876 check_return_expr (tree retval)
5879 /* The type actually returned by the function, after any
5882 int fn_returns_value_p;
5884 /* A `volatile' function is one that isn't supposed to return, ever.
5885 (This is a G++ extension, used to get better code for functions
5886 that call the `volatile' function.) */
5887 if (TREE_THIS_VOLATILE (current_function_decl))
5888 warning ("function declared `noreturn' has a `return' statement");
5890 /* Check for various simple errors. */
5891 if (DECL_DESTRUCTOR_P (current_function_decl))
5894 error ("returning a value from a destructor");
5897 else if (DECL_CONSTRUCTOR_P (current_function_decl))
5899 if (in_function_try_handler)
5900 /* If a return statement appears in a handler of the
5901 function-try-block of a constructor, the program is ill-formed. */
5902 error ("cannot return from a handler of a function-try-block of a constructor");
5904 /* You can't return a value from a constructor. */
5905 error ("returning a value from a constructor");
5909 if (processing_template_decl)
5911 current_function_returns_value = 1;
5915 /* When no explicit return-value is given in a function with a named
5916 return value, the named return value is used. */
5917 result = DECL_RESULT (current_function_decl);
5918 valtype = TREE_TYPE (result);
5919 my_friendly_assert (valtype != NULL_TREE, 19990924);
5920 fn_returns_value_p = !VOID_TYPE_P (valtype);
5921 if (!retval && DECL_NAME (result) && fn_returns_value_p)
5924 /* Check for a return statement with no return value in a function
5925 that's supposed to return a value. */
5926 if (!retval && fn_returns_value_p)
5928 pedwarn ("return-statement with no value, in function returning '%T'",
5930 /* Clear this, so finish_function won't say that we reach the
5931 end of a non-void function (which we don't, we gave a
5933 current_function_returns_null = 0;
5935 /* Check for a return statement with a value in a function that
5936 isn't supposed to return a value. */
5937 else if (retval && !fn_returns_value_p)
5939 if (VOID_TYPE_P (TREE_TYPE (retval)))
5940 /* You can return a `void' value from a function of `void'
5941 type. In that case, we have to evaluate the expression for
5942 its side-effects. */
5943 finish_expr_stmt (retval);
5945 pedwarn ("return-statement with a value, in function "
5946 "returning 'void'");
5948 current_function_returns_null = 1;
5950 /* There's really no value to return, after all. */
5954 /* Remember that this function can sometimes return without a
5956 current_function_returns_null = 1;
5958 /* Remember that this function did return a value. */
5959 current_function_returns_value = 1;
5961 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
5962 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
5963 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
5964 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
5966 && null_ptr_cst_p (retval))
5967 warning ("`operator new' must not return NULL unless it is declared `throw()' (or -fcheck-new is in effect)");
5969 /* Effective C++ rule 15. See also start_function. */
5971 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR)
5972 && retval != current_class_ref)
5973 warning ("`operator=' should return a reference to `*this'");
5975 /* The fabled Named Return Value optimization, as per [class.copy]/15:
5977 [...] For a function with a class return type, if the expression
5978 in the return statement is the name of a local object, and the cv-
5979 unqualified type of the local object is the same as the function
5980 return type, an implementation is permitted to omit creating the tem-
5981 porary object to hold the function return value [...]
5983 So, if this is a value-returning function that always returns the same
5984 local variable, remember it.
5986 It might be nice to be more flexible, and choose the first suitable
5987 variable even if the function sometimes returns something else, but
5988 then we run the risk of clobbering the variable we chose if the other
5989 returned expression uses the chosen variable somehow. And people expect
5990 this restriction, anyway. (jason 2000-11-19)
5992 See finish_function, cxx_expand_function_start, and
5993 cp_copy_res_decl_for_inlining for other pieces of this
5996 if (fn_returns_value_p && flag_elide_constructors)
5998 if (retval != NULL_TREE
5999 && (current_function_return_value == NULL_TREE
6000 || current_function_return_value == retval)
6001 && TREE_CODE (retval) == VAR_DECL
6002 && DECL_CONTEXT (retval) == current_function_decl
6003 && ! TREE_STATIC (retval)
6004 && (DECL_ALIGN (retval)
6005 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6006 && same_type_p ((TYPE_MAIN_VARIANT
6007 (TREE_TYPE (retval))),
6009 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
6010 current_function_return_value = retval;
6012 current_function_return_value = error_mark_node;
6015 /* We don't need to do any conversions when there's nothing being
6017 if (!retval || retval == error_mark_node)
6020 /* Do any required conversions. */
6021 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6022 /* No conversions are required. */
6026 /* The type the function is declared to return. */
6027 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6029 /* First convert the value to the function's return type, then
6030 to the type of return value's location to handle the
6031 case that functype is smaller than the valtype. */
6032 retval = convert_for_initialization
6033 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6034 "return", NULL_TREE, 0);
6035 retval = convert (valtype, retval);
6037 /* If the conversion failed, treat this just like `return;'. */
6038 if (retval == error_mark_node)
6040 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6041 else if (! current_function_returns_struct
6042 && TREE_CODE (retval) == TARGET_EXPR
6043 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6044 retval = build (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6045 TREE_OPERAND (retval, 0));
6047 maybe_warn_about_returning_address_of_local (retval);
6050 /* Actually copy the value returned into the appropriate location. */
6051 if (retval && retval != result)
6052 retval = build (INIT_EXPR, TREE_TYPE (result), result, retval);
6058 /* Returns nonzero if the pointer-type FROM can be converted to the
6059 pointer-type TO via a qualification conversion. If CONSTP is -1,
6060 then we return nonzero if the pointers are similar, and the
6061 cv-qualification signature of FROM is a proper subset of that of TO.
6063 If CONSTP is positive, then all outer pointers have been
6067 comp_ptr_ttypes_real (tree to, tree from, int constp)
6069 bool to_more_cv_qualified = false;
6071 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6073 if (TREE_CODE (to) != TREE_CODE (from))
6076 if (TREE_CODE (from) == OFFSET_TYPE
6077 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6078 TYPE_OFFSET_BASETYPE (to)))
6081 /* Const and volatile mean something different for function types,
6082 so the usual checks are not appropriate. */
6083 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6085 if (!at_least_as_qualified_p (to, from))
6088 if (!at_least_as_qualified_p (from, to))
6092 to_more_cv_qualified = true;
6096 constp &= TYPE_READONLY (to);
6099 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6100 return ((constp >= 0 || to_more_cv_qualified)
6101 && same_type_ignoring_top_level_qualifiers_p (to, from));
6105 /* When comparing, say, char ** to char const **, this function takes
6106 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6107 types to this function. */
6110 comp_ptr_ttypes (tree to, tree from)
6112 return comp_ptr_ttypes_real (to, from, 1);
6115 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6116 type or inheritance-related types, regardless of cv-quals. */
6119 ptr_reasonably_similar (tree to, tree from)
6121 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6123 /* Any target type is similar enough to void. */
6124 if (TREE_CODE (to) == VOID_TYPE
6125 || TREE_CODE (from) == VOID_TYPE)
6128 if (TREE_CODE (to) != TREE_CODE (from))
6131 if (TREE_CODE (from) == OFFSET_TYPE
6132 && comptypes (TYPE_OFFSET_BASETYPE (to),
6133 TYPE_OFFSET_BASETYPE (from),
6134 COMPARE_BASE | COMPARE_DERIVED))
6137 if (TREE_CODE (to) == INTEGER_TYPE
6138 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6141 if (TREE_CODE (to) == FUNCTION_TYPE)
6144 if (TREE_CODE (to) != POINTER_TYPE)
6146 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6147 COMPARE_BASE | COMPARE_DERIVED);
6151 /* Like comp_ptr_ttypes, for const_cast. */
6154 comp_ptr_ttypes_const (tree to, tree from)
6156 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6158 if (TREE_CODE (to) != TREE_CODE (from))
6161 if (TREE_CODE (from) == OFFSET_TYPE
6162 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6163 TYPE_OFFSET_BASETYPE (to)))
6166 if (TREE_CODE (to) != POINTER_TYPE)
6167 return same_type_ignoring_top_level_qualifiers_p (to, from);
6171 /* Returns the type qualifiers for this type, including the qualifiers on the
6172 elements for an array type. */
6175 cp_type_quals (tree type)
6177 type = strip_array_types (type);
6178 if (type == error_mark_node)
6179 return TYPE_UNQUALIFIED;
6180 return TYPE_QUALS (type);
6183 /* Returns nonzero if the TYPE contains a mutable member */
6186 cp_has_mutable_p (tree type)
6188 type = strip_array_types (type);
6190 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6193 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6194 exemplar types such that casting T1 to T2 is casting away castness
6195 if and only if there is no implicit conversion from T1 to T2. */
6198 casts_away_constness_r (tree *t1, tree *t2)
6203 /* [expr.const.cast]
6205 For multi-level pointer to members and multi-level mixed pointers
6206 and pointers to members (conv.qual), the "member" aspect of a
6207 pointer to member level is ignored when determining if a const
6208 cv-qualifier has been cast away. */
6209 if (TYPE_PTRMEM_P (*t1))
6210 *t1 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t1));
6211 if (TYPE_PTRMEM_P (*t2))
6212 *t2 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t2));
6214 /* [expr.const.cast]
6216 For two pointer types:
6218 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6219 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6222 casting from X1 to X2 casts away constness if, for a non-pointer
6223 type T there does not exist an implicit conversion (clause
6226 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6230 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6232 if (TREE_CODE (*t1) != POINTER_TYPE
6233 || TREE_CODE (*t2) != POINTER_TYPE)
6235 *t1 = cp_build_qualified_type (void_type_node,
6236 cp_type_quals (*t1));
6237 *t2 = cp_build_qualified_type (void_type_node,
6238 cp_type_quals (*t2));
6242 quals1 = cp_type_quals (*t1);
6243 quals2 = cp_type_quals (*t2);
6244 *t1 = TREE_TYPE (*t1);
6245 *t2 = TREE_TYPE (*t2);
6246 casts_away_constness_r (t1, t2);
6247 *t1 = build_pointer_type (*t1);
6248 *t2 = build_pointer_type (*t2);
6249 *t1 = cp_build_qualified_type (*t1, quals1);
6250 *t2 = cp_build_qualified_type (*t2, quals2);
6253 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6257 casts_away_constness (tree t1, tree t2)
6259 if (TREE_CODE (t2) == REFERENCE_TYPE)
6261 /* [expr.const.cast]
6263 Casting from an lvalue of type T1 to an lvalue of type T2
6264 using a reference cast casts away constness if a cast from an
6265 rvalue of type "pointer to T1" to the type "pointer to T2"
6266 casts away constness. */
6267 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6268 return casts_away_constness (build_pointer_type (t1),
6269 build_pointer_type (TREE_TYPE (t2)));
6272 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6273 /* [expr.const.cast]
6275 Casting from an rvalue of type "pointer to data member of X
6276 of type T1" to the type "pointer to data member of Y of type
6277 T2" casts away constness if a cast from an rvalue of type
6278 "pointer to T1" to the type "pointer to T2" casts away
6280 return casts_away_constness
6281 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6282 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6284 /* Casting away constness is only something that makes sense for
6285 pointer or reference types. */
6286 if (TREE_CODE (t1) != POINTER_TYPE
6287 || TREE_CODE (t2) != POINTER_TYPE)
6290 /* Top-level qualifiers don't matter. */
6291 t1 = TYPE_MAIN_VARIANT (t1);
6292 t2 = TYPE_MAIN_VARIANT (t2);
6293 casts_away_constness_r (&t1, &t2);
6294 if (!can_convert (t2, t1))
6300 /* If T is a REFERENCE_TYPE return the type to which T refers.
6301 Otherwise, return T itself. */
6304 non_reference (tree t)
6306 if (TREE_CODE (t) == REFERENCE_TYPE)