1 /* Build expressions with type checking for C++ compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
4 Hacked by Michael Tiemann (tiemann@cygnus.com)
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to
20 the Free Software Foundation, 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
24 /* This file is part of the C++ front end.
25 It contains routines to build C++ expressions given their operands,
26 including computing the types of the result, C and C++ specific error
27 checks, and some optimization.
29 There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
30 and to process initializations in declarations (since they work
31 like a strange sort of assignment). */
35 #include "coretypes.h"
45 #include "diagnostic.h"
49 static tree convert_for_assignment (tree, tree, const char *, tree, int);
50 static tree cp_pointer_int_sum (enum tree_code, tree, tree);
51 static tree rationalize_conditional_expr (enum tree_code, tree);
52 static int comp_ptr_ttypes_real (tree, tree, int);
53 static int comp_ptr_ttypes_const (tree, tree);
54 static bool comp_except_types (tree, tree, bool);
55 static bool comp_array_types (tree, tree, bool);
56 static tree common_base_type (tree, tree);
57 static tree pointer_diff (tree, tree, tree);
58 static tree get_delta_difference (tree, tree, int);
59 static void casts_away_constness_r (tree *, tree *);
60 static bool casts_away_constness (tree, tree);
61 static void maybe_warn_about_returning_address_of_local (tree);
62 static tree lookup_destructor (tree, tree, tree);
64 /* Return the target type of TYPE, which means return T for:
65 T*, T&, T[], T (...), and otherwise, just T. */
68 target_type (tree type)
70 type = non_reference (type);
71 while (TREE_CODE (type) == POINTER_TYPE
72 || TREE_CODE (type) == ARRAY_TYPE
73 || TREE_CODE (type) == FUNCTION_TYPE
74 || TREE_CODE (type) == METHOD_TYPE
75 || TYPE_PTRMEM_P (type))
76 type = TREE_TYPE (type);
80 /* Do `exp = require_complete_type (exp);' to make sure exp
81 does not have an incomplete type. (That includes void types.)
82 Returns the error_mark_node if the VALUE does not have
83 complete type when this function returns. */
86 require_complete_type (tree value)
90 if (processing_template_decl || value == error_mark_node)
93 if (TREE_CODE (value) == OVERLOAD)
94 type = unknown_type_node;
96 type = TREE_TYPE (value);
98 if (type == error_mark_node)
99 return error_mark_node;
101 /* First, detect a valid value with a complete type. */
102 if (COMPLETE_TYPE_P (type))
105 if (complete_type_or_else (type, value))
108 return error_mark_node;
111 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
112 a template instantiation, do the instantiation. Returns TYPE,
113 whether or not it could be completed, unless something goes
114 horribly wrong, in which case the error_mark_node is returned. */
117 complete_type (tree type)
119 if (type == NULL_TREE)
120 /* Rather than crash, we return something sure to cause an error
122 return error_mark_node;
124 if (type == error_mark_node || COMPLETE_TYPE_P (type))
126 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
128 tree t = complete_type (TREE_TYPE (type));
129 if (COMPLETE_TYPE_P (t) && !dependent_type_p (type))
131 TYPE_NEEDS_CONSTRUCTING (type)
132 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
133 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
134 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
136 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
137 instantiate_class_template (TYPE_MAIN_VARIANT (type));
142 /* Like complete_type, but issue an error if the TYPE cannot be completed.
143 VALUE is used for informative diagnostics. DIAG_TYPE indicates the type
144 of diagnostic: 0 for an error, 1 for a warning, 2 for a pedwarn.
145 Returns NULL_TREE if the type cannot be made complete. */
148 complete_type_or_diagnostic (tree type, tree value, int diag_type)
150 type = complete_type (type);
151 if (type == error_mark_node)
152 /* We already issued an error. */
154 else if (!COMPLETE_TYPE_P (type))
156 cxx_incomplete_type_diagnostic (value, type, diag_type);
163 /* Return truthvalue of whether type of EXP is instantiated. */
166 type_unknown_p (tree exp)
168 return (TREE_CODE (exp) == TREE_LIST
169 || TREE_TYPE (exp) == unknown_type_node);
173 /* Return the common type of two parameter lists.
174 We assume that comptypes has already been done and returned 1;
175 if that isn't so, this may crash.
177 As an optimization, free the space we allocate if the parameter
178 lists are already common. */
181 commonparms (tree p1, tree p2)
183 tree oldargs = p1, newargs, n;
187 len = list_length (p1);
188 newargs = tree_last (p1);
190 if (newargs == void_list_node)
199 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
204 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
206 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
208 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
211 else if (! TREE_PURPOSE (p1))
213 if (TREE_PURPOSE (p2))
215 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
221 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
223 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
225 if (TREE_VALUE (p1) != TREE_VALUE (p2))
228 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
231 TREE_VALUE (n) = TREE_VALUE (p1);
239 /* Given a type, perhaps copied for a typedef,
240 find the "original" version of it. */
242 original_type (tree t)
244 while (TYPE_NAME (t) != NULL_TREE)
246 tree x = TYPE_NAME (t);
247 if (TREE_CODE (x) != TYPE_DECL)
249 x = DECL_ORIGINAL_TYPE (x);
257 /* T1 and T2 are arithmetic or enumeration types. Return the type
258 that will result from the "usual arithmetic conversions" on T1 and
259 T2 as described in [expr]. */
262 type_after_usual_arithmetic_conversions (tree t1, tree t2)
264 enum tree_code code1 = TREE_CODE (t1);
265 enum tree_code code2 = TREE_CODE (t2);
268 /* FIXME: Attributes. */
269 my_friendly_assert (ARITHMETIC_TYPE_P (t1)
270 || TREE_CODE (t1) == COMPLEX_TYPE
271 || TREE_CODE (t1) == ENUMERAL_TYPE,
273 my_friendly_assert (ARITHMETIC_TYPE_P (t2)
274 || TREE_CODE (t2) == COMPLEX_TYPE
275 || TREE_CODE (t2) == ENUMERAL_TYPE,
278 /* In what follows, we slightly generalize the rules given in [expr] so
279 as to deal with `long long' and `complex'. First, merge the
281 attributes = (*targetm.merge_type_attributes) (t1, t2);
283 /* If one type is complex, form the common type of the non-complex
284 components, then make that complex. Use T1 or T2 if it is the
286 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
288 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
289 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
291 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
293 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
294 return build_type_attribute_variant (t1, attributes);
295 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
296 return build_type_attribute_variant (t2, attributes);
298 return build_type_attribute_variant (build_complex_type (subtype),
302 /* If only one is real, use it as the result. */
303 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
304 return build_type_attribute_variant (t1, attributes);
305 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
306 return build_type_attribute_variant (t2, attributes);
308 /* Perform the integral promotions. */
309 if (code1 != REAL_TYPE)
311 t1 = type_promotes_to (t1);
312 t2 = type_promotes_to (t2);
315 /* Both real or both integers; use the one with greater precision. */
316 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
317 return build_type_attribute_variant (t1, attributes);
318 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
319 return build_type_attribute_variant (t2, attributes);
321 /* The types are the same; no need to do anything fancy. */
322 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
323 return build_type_attribute_variant (t1, attributes);
325 if (code1 != REAL_TYPE)
327 /* If one is a sizetype, use it so size_binop doesn't blow up. */
328 if (TYPE_IS_SIZETYPE (t1) > TYPE_IS_SIZETYPE (t2))
329 return build_type_attribute_variant (t1, attributes);
330 if (TYPE_IS_SIZETYPE (t2) > TYPE_IS_SIZETYPE (t1))
331 return build_type_attribute_variant (t2, attributes);
333 /* If one is unsigned long long, then convert the other to unsigned
335 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
336 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
337 return build_type_attribute_variant (long_long_unsigned_type_node,
339 /* If one is a long long, and the other is an unsigned long, and
340 long long can represent all the values of an unsigned long, then
341 convert to a long long. Otherwise, convert to an unsigned long
342 long. Otherwise, if either operand is long long, convert the
345 Since we're here, we know the TYPE_PRECISION is the same;
346 therefore converting to long long cannot represent all the values
347 of an unsigned long, so we choose unsigned long long in that
349 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
350 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
352 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
353 ? long_long_unsigned_type_node
354 : long_long_integer_type_node);
355 return build_type_attribute_variant (t, attributes);
358 /* Go through the same procedure, but for longs. */
359 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
360 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
361 return build_type_attribute_variant (long_unsigned_type_node,
363 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
364 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
366 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
367 ? long_unsigned_type_node : long_integer_type_node);
368 return build_type_attribute_variant (t, attributes);
370 /* Otherwise prefer the unsigned one. */
371 if (TYPE_UNSIGNED (t1))
372 return build_type_attribute_variant (t1, attributes);
374 return build_type_attribute_variant (t2, attributes);
378 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
379 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
380 return build_type_attribute_variant (long_double_type_node,
382 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
383 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
384 return build_type_attribute_variant (double_type_node,
386 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
387 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
388 return build_type_attribute_variant (float_type_node,
391 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
392 the standard C++ floating-point types. Logic earlier in this
393 function has already eliminated the possibility that
394 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
395 compelling reason to choose one or the other. */
396 return build_type_attribute_variant (t1, attributes);
400 /* Subroutine of composite_pointer_type to implement the recursive
401 case. See that function for documentation fo the parameters. */
404 composite_pointer_type_r (tree t1, tree t2, const char* location)
411 /* Determine the types pointed to by T1 and T2. */
412 if (TREE_CODE (t1) == POINTER_TYPE)
414 pointee1 = TREE_TYPE (t1);
415 pointee2 = TREE_TYPE (t2);
419 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
420 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
425 Otherwise, the composite pointer type is a pointer type
426 similar (_conv.qual_) to the type of one of the operands,
427 with a cv-qualification signature (_conv.qual_) that is the
428 union of the cv-qualification signatures of the operand
430 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
431 result_type = pointee1;
432 else if ((TREE_CODE (pointee1) == POINTER_TYPE
433 && TREE_CODE (pointee2) == POINTER_TYPE)
434 || (TYPE_PTR_TO_MEMBER_P (pointee1)
435 && TYPE_PTR_TO_MEMBER_P (pointee2)))
436 result_type = composite_pointer_type_r (pointee1, pointee2, location);
439 pedwarn ("%s between distinct pointer types `%T' and `%T' "
442 result_type = void_type_node;
444 result_type = cp_build_qualified_type (result_type,
445 (cp_type_quals (pointee1)
446 | cp_type_quals (pointee2)));
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 result_type = build_pointer_type (result_type);
462 /* Merge the attributes. */
463 attributes = (*targetm.merge_type_attributes) (t1, t2);
464 return build_type_attribute_variant (result_type, attributes);
467 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
468 ARG1 and ARG2 are the values with those types. The LOCATION is a
469 string describing the current location, in case an error occurs.
471 This routine also implements the computation of a common type for
472 pointers-to-members as per [expr.eq]. */
475 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
476 const char* location)
483 If one operand is a null pointer constant, the composite pointer
484 type is the type of the other operand. */
485 if (null_ptr_cst_p (arg1))
487 if (null_ptr_cst_p (arg2))
494 If one of the operands has type "pointer to cv1 void*", then
495 the other has type "pointer to cv2T", and the composite pointer
496 type is "pointer to cv12 void", where cv12 is the union of cv1
499 If either type is a pointer to void, make sure it is T1. */
500 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
508 /* Now, if T1 is a pointer to void, merge the qualifiers. */
509 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
514 if (pedantic && TYPE_PTRFN_P (t2))
515 pedwarn ("ISO C++ forbids %s between pointer of type `void *' and pointer-to-function", location);
517 = cp_build_qualified_type (void_type_node,
518 (cp_type_quals (TREE_TYPE (t1))
519 | cp_type_quals (TREE_TYPE (t2))));
520 result_type = build_pointer_type (result_type);
521 /* Merge the attributes. */
522 attributes = (*targetm.merge_type_attributes) (t1, t2);
523 return build_type_attribute_variant (result_type, attributes);
526 /* [expr.eq] permits the application of a pointer conversion to
527 bring the pointers to a common type. */
528 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
529 && CLASS_TYPE_P (TREE_TYPE (t1))
530 && CLASS_TYPE_P (TREE_TYPE (t2))
531 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
534 class1 = TREE_TYPE (t1);
535 class2 = TREE_TYPE (t2);
537 if (DERIVED_FROM_P (class1, class2))
538 t2 = (build_pointer_type
539 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
540 else if (DERIVED_FROM_P (class2, class1))
541 t1 = (build_pointer_type
542 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
545 error ("%s between distinct pointer types `%T' and `%T' "
546 "lacks a cast", location, t1, t2);
547 return error_mark_node;
550 /* [expr.eq] permits the application of a pointer-to-member
551 conversion to change the class type of one of the types. */
552 else if (TYPE_PTR_TO_MEMBER_P (t1)
553 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
554 TYPE_PTRMEM_CLASS_TYPE (t2)))
556 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
557 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
559 if (DERIVED_FROM_P (class1, class2))
560 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
561 else if (DERIVED_FROM_P (class2, class1))
562 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
565 error ("%s between distinct pointer-to-member types `%T' and `%T' "
566 "lacks a cast", location, t1, t2);
567 return error_mark_node;
571 return composite_pointer_type_r (t1, t2, location);
574 /* Return the merged type of two types.
575 We assume that comptypes has already been done and returned 1;
576 if that isn't so, this may crash.
578 This just combines attributes and default arguments; any other
579 differences would cause the two types to compare unalike. */
582 merge_types (tree t1, tree t2)
584 enum tree_code code1;
585 enum tree_code code2;
588 /* Save time if the two types are the same. */
591 if (original_type (t1) == original_type (t2))
594 /* If one type is nonsense, use the other. */
595 if (t1 == error_mark_node)
597 if (t2 == error_mark_node)
600 /* Merge the attributes. */
601 attributes = (*targetm.merge_type_attributes) (t1, t2);
603 if (TYPE_PTRMEMFUNC_P (t1))
604 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
605 if (TYPE_PTRMEMFUNC_P (t2))
606 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
608 code1 = TREE_CODE (t1);
609 code2 = TREE_CODE (t2);
615 /* For two pointers, do this recursively on the target type. */
617 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
618 int quals = cp_type_quals (t1);
620 if (code1 == POINTER_TYPE)
621 t1 = build_pointer_type (target);
623 t1 = build_reference_type (target);
624 t1 = build_type_attribute_variant (t1, attributes);
625 t1 = cp_build_qualified_type (t1, quals);
627 if (TREE_CODE (target) == METHOD_TYPE)
628 t1 = build_ptrmemfunc_type (t1);
637 quals = cp_type_quals (t1);
638 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
639 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
640 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
642 t1 = cp_build_qualified_type (t1, quals);
648 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
649 /* Save space: see if the result is identical to one of the args. */
650 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
651 return build_type_attribute_variant (t1, attributes);
652 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
653 return build_type_attribute_variant (t2, attributes);
654 /* Merge the element types, and have a size if either arg has one. */
655 t1 = build_cplus_array_type
656 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
661 /* Function types: prefer the one that specified arg types.
662 If both do, merge the arg types. Also merge the return types. */
664 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
665 tree p1 = TYPE_ARG_TYPES (t1);
666 tree p2 = TYPE_ARG_TYPES (t2);
669 /* Save space: see if the result is identical to one of the args. */
670 if (valtype == TREE_TYPE (t1) && ! p2)
671 return cp_build_type_attribute_variant (t1, attributes);
672 if (valtype == TREE_TYPE (t2) && ! p1)
673 return cp_build_type_attribute_variant (t2, attributes);
675 /* Simple way if one arg fails to specify argument types. */
676 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
678 rval = build_function_type (valtype, p2);
679 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
680 rval = build_exception_variant (rval, raises);
681 return cp_build_type_attribute_variant (rval, attributes);
683 raises = TYPE_RAISES_EXCEPTIONS (t1);
684 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
686 rval = build_function_type (valtype, p1);
688 rval = build_exception_variant (rval, raises);
689 return cp_build_type_attribute_variant (rval, attributes);
692 rval = build_function_type (valtype, commonparms (p1, p2));
693 t1 = build_exception_variant (rval, raises);
699 /* Get this value the long way, since TYPE_METHOD_BASETYPE
700 is just the main variant of this. */
701 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
702 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
705 /* If this was a member function type, get back to the
706 original type of type member function (i.e., without
707 the class instance variable up front. */
708 t1 = build_function_type (TREE_TYPE (t1),
709 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
710 t2 = build_function_type (TREE_TYPE (t2),
711 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
712 t3 = merge_types (t1, t2);
713 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
714 TYPE_ARG_TYPES (t3));
715 t1 = build_exception_variant (t3, raises);
720 /* There is no need to merge attributes into a TYPENAME_TYPE.
721 When the type is instantiated it will have whatever
722 attributes result from the instantiation. */
727 return cp_build_type_attribute_variant (t1, attributes);
730 /* Return the common type of two types.
731 We assume that comptypes has already been done and returned 1;
732 if that isn't so, this may crash.
734 This is the type for the result of most arithmetic operations
735 if the operands have the given two types. */
738 common_type (tree t1, tree t2)
740 enum tree_code code1;
741 enum tree_code code2;
743 /* If one type is nonsense, bail. */
744 if (t1 == error_mark_node || t2 == error_mark_node)
745 return error_mark_node;
747 code1 = TREE_CODE (t1);
748 code2 = TREE_CODE (t2);
750 if ((ARITHMETIC_TYPE_P (t1) || code1 == ENUMERAL_TYPE
751 || code1 == COMPLEX_TYPE)
752 && (ARITHMETIC_TYPE_P (t2) || code2 == ENUMERAL_TYPE
753 || code2 == COMPLEX_TYPE))
754 return type_after_usual_arithmetic_conversions (t1, t2);
756 else if ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
757 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
758 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)))
759 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
765 /* Compare two exception specifier types for exactness or subsetness, if
766 allowed. Returns false for mismatch, true for match (same, or
769 [except.spec] "If a class X ... objects of class X or any class publicly
770 and unambiguously derived from X. Similarly, if a pointer type Y * ...
771 exceptions of type Y * or that are pointers to any type publicly and
772 unambiguously derived from Y. Otherwise a function only allows exceptions
773 that have the same type ..."
774 This does not mention cv qualifiers and is different to what throw
775 [except.throw] and catch [except.catch] will do. They will ignore the
776 top level cv qualifiers, and allow qualifiers in the pointer to class
779 We implement the letter of the standard. */
782 comp_except_types (tree a, tree b, bool exact)
784 if (same_type_p (a, b))
788 if (cp_type_quals (a) || cp_type_quals (b))
791 if (TREE_CODE (a) == POINTER_TYPE
792 && TREE_CODE (b) == POINTER_TYPE)
796 if (cp_type_quals (a) || cp_type_quals (b))
800 if (TREE_CODE (a) != RECORD_TYPE
801 || TREE_CODE (b) != RECORD_TYPE)
804 if (ACCESSIBLY_UNIQUELY_DERIVED_P (a, b))
810 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
811 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
812 otherwise it must be exact. Exception lists are unordered, but
813 we've already filtered out duplicates. Most lists will be in order,
814 we should try to make use of that. */
817 comp_except_specs (tree t1, tree t2, bool exact)
826 if (t1 == NULL_TREE) /* T1 is ... */
827 return t2 == NULL_TREE || !exact;
828 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
829 return t2 != NULL_TREE && !TREE_VALUE (t2);
830 if (t2 == NULL_TREE) /* T2 is ... */
832 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
835 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
836 Count how many we find, to determine exactness. For exact matching and
837 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
839 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
841 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
843 tree a = TREE_VALUE (probe);
844 tree b = TREE_VALUE (t2);
846 if (comp_except_types (a, b, exact))
848 if (probe == base && exact)
849 base = TREE_CHAIN (probe);
854 if (probe == NULL_TREE)
857 return !exact || base == NULL_TREE || length == list_length (t1);
860 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
861 [] can match [size]. */
864 comp_array_types (tree t1, tree t2, bool allow_redeclaration)
873 /* The type of the array elements must be the same. */
874 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
877 d1 = TYPE_DOMAIN (t1);
878 d2 = TYPE_DOMAIN (t2);
883 /* If one of the arrays is dimensionless, and the other has a
884 dimension, they are of different types. However, it is valid to
892 declarations for an array object can specify
893 array types that differ by the presence or absence of a major
894 array bound (_dcl.array_). */
896 return allow_redeclaration;
898 /* Check that the dimensions are the same. */
900 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
902 max1 = TYPE_MAX_VALUE (d1);
903 max2 = TYPE_MAX_VALUE (d2);
904 if (processing_template_decl && !abi_version_at_least (2)
905 && !value_dependent_expression_p (max1)
906 && !value_dependent_expression_p (max2))
908 /* With abi-1 we do not fold non-dependent array bounds, (and
909 consequently mangle them incorrectly). We must therefore
910 fold them here, to verify the domains have the same
916 if (!cp_tree_equal (max1, max2))
922 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
923 is a bitwise-or of the COMPARE_* flags. */
926 comptypes (tree t1, tree t2, int strict)
931 /* Suppress errors caused by previously reported errors. */
932 if (t1 == error_mark_node || t2 == error_mark_node)
935 my_friendly_assert (TYPE_P (t1) && TYPE_P (t2), 20030623);
937 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
938 current instantiation. */
939 if (TREE_CODE (t1) == TYPENAME_TYPE)
941 tree resolved = resolve_typename_type (t1, /*only_current_p=*/true);
943 if (resolved != error_mark_node)
947 if (TREE_CODE (t2) == TYPENAME_TYPE)
949 tree resolved = resolve_typename_type (t2, /*only_current_p=*/true);
951 if (resolved != error_mark_node)
955 /* If either type is the internal version of sizetype, use the
957 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
958 && TYPE_ORIG_SIZE_TYPE (t1))
959 t1 = TYPE_ORIG_SIZE_TYPE (t1);
961 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
962 && TYPE_ORIG_SIZE_TYPE (t2))
963 t2 = TYPE_ORIG_SIZE_TYPE (t2);
965 if (TYPE_PTRMEMFUNC_P (t1))
966 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
967 if (TYPE_PTRMEMFUNC_P (t2))
968 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
970 /* Different classes of types can't be compatible. */
971 if (TREE_CODE (t1) != TREE_CODE (t2))
974 /* Qualifiers must match. For array types, we will check when we
975 recur on the array element types. */
976 if (TREE_CODE (t1) != ARRAY_TYPE
977 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
979 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
982 /* Allow for two different type nodes which have essentially the same
983 definition. Note that we already checked for equality of the type
984 qualifiers (just above). */
986 if (TREE_CODE (t1) != ARRAY_TYPE
987 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
990 if (!(*targetm.comp_type_attributes) (t1, t2))
993 switch (TREE_CODE (t1))
995 case TEMPLATE_TEMPLATE_PARM:
996 case BOUND_TEMPLATE_TEMPLATE_PARM:
997 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
998 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1000 if (!comp_template_parms
1001 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1002 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1004 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1006 /* Don't check inheritance. */
1007 strict = COMPARE_STRICT;
1012 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1013 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1014 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1015 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1018 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1020 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1026 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1027 strict & ~COMPARE_REDECLARATION))
1032 case REFERENCE_TYPE:
1033 return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1037 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1039 return compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2));
1042 /* Target types must match incl. qualifiers. */
1043 return comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION));
1045 case TEMPLATE_TYPE_PARM:
1046 return (TEMPLATE_TYPE_IDX (t1) == TEMPLATE_TYPE_IDX (t2)
1047 && TEMPLATE_TYPE_LEVEL (t1) == TEMPLATE_TYPE_LEVEL (t2));
1050 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1051 TYPENAME_TYPE_FULLNAME (t2)))
1053 return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
1055 case UNBOUND_CLASS_TEMPLATE:
1056 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1058 return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
1061 return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1064 return TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
1065 && same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1074 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1077 at_least_as_qualified_p (tree type1, tree type2)
1079 int q1 = cp_type_quals (type1);
1080 int q2 = cp_type_quals (type2);
1082 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1083 return (q1 & q2) == q2;
1086 /* Returns 1 if TYPE1 is more qualified than TYPE2. */
1089 more_qualified_p (tree type1, tree type2)
1091 int q1 = cp_type_quals (type1);
1092 int q2 = cp_type_quals (type2);
1094 return q1 != q2 && (q1 & q2) == q2;
1097 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1098 more cv-qualified that TYPE1, and 0 otherwise. */
1101 comp_cv_qualification (tree type1, tree type2)
1103 int q1 = cp_type_quals (type1);
1104 int q2 = cp_type_quals (type2);
1109 if ((q1 & q2) == q2)
1111 else if ((q1 & q2) == q1)
1117 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1118 subset of the cv-qualification signature of TYPE2, and the types
1119 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1122 comp_cv_qual_signature (tree type1, tree type2)
1124 if (comp_ptr_ttypes_real (type2, type1, -1))
1126 else if (comp_ptr_ttypes_real (type1, type2, -1))
1132 /* If two types share a common base type, return that basetype.
1133 If there is not a unique most-derived base type, this function
1134 returns ERROR_MARK_NODE. */
1137 common_base_type (tree tt1, tree tt2)
1139 tree best = NULL_TREE;
1142 /* If one is a baseclass of another, that's good enough. */
1143 if (UNIQUELY_DERIVED_FROM_P (tt1, tt2))
1145 if (UNIQUELY_DERIVED_FROM_P (tt2, tt1))
1148 /* Otherwise, try to find a unique baseclass of TT1
1149 that is shared by TT2, and follow that down. */
1150 for (i = CLASSTYPE_N_BASECLASSES (tt1)-1; i >= 0; i--)
1152 tree basetype = TYPE_BINFO_BASETYPE (tt1, i);
1153 tree trial = common_base_type (basetype, tt2);
1156 if (trial == error_mark_node)
1158 if (best == NULL_TREE)
1160 else if (best != trial)
1161 return error_mark_node;
1166 for (i = CLASSTYPE_N_BASECLASSES (tt2)-1; i >= 0; i--)
1168 tree basetype = TYPE_BINFO_BASETYPE (tt2, i);
1169 tree trial = common_base_type (tt1, basetype);
1172 if (trial == error_mark_node)
1174 if (best == NULL_TREE)
1176 else if (best != trial)
1177 return error_mark_node;
1183 /* Subroutines of `comptypes'. */
1185 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1186 equivalent in the sense that functions with those parameter types
1187 can have equivalent types. The two lists must be equivalent,
1188 element by element. */
1191 compparms (tree parms1, tree parms2)
1195 /* An unspecified parmlist matches any specified parmlist
1196 whose argument types don't need default promotions. */
1198 for (t1 = parms1, t2 = parms2;
1200 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1202 /* If one parmlist is shorter than the other,
1203 they fail to match. */
1206 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1213 /* Process a sizeof or alignof expression where the operand is a
1217 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1219 enum tree_code type_code;
1221 const char *op_name;
1223 my_friendly_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR, 20020720);
1224 if (type == error_mark_node)
1225 return error_mark_node;
1227 if (processing_template_decl)
1229 value = build_min (op, size_type_node, type);
1230 TREE_READONLY (value) = 1;
1234 op_name = operator_name_info[(int) op].name;
1236 type = non_reference (type);
1237 type_code = TREE_CODE (type);
1239 if (type_code == METHOD_TYPE)
1241 if (complain && (pedantic || warn_pointer_arith))
1242 pedwarn ("invalid application of `%s' to a member function", op_name);
1243 value = size_one_node;
1246 value = c_sizeof_or_alignof_type (complete_type (type), op, complain);
1251 /* Process a sizeof or alignof expression where the operand is an
1255 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op)
1257 const char *op_name = operator_name_info[(int) op].name;
1259 if (e == error_mark_node)
1260 return error_mark_node;
1262 if (processing_template_decl)
1264 e = build_min (op, size_type_node, e);
1265 TREE_SIDE_EFFECTS (e) = 0;
1266 TREE_READONLY (e) = 1;
1271 if (TREE_CODE (e) == COMPONENT_REF
1272 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1273 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1275 error ("invalid application of `%s' to a bit-field", op_name);
1278 else if (is_overloaded_fn (e))
1280 pedwarn ("ISO C++ forbids applying `%s' to an expression of function type", op_name);
1283 else if (type_unknown_p (e))
1285 cxx_incomplete_type_error (e, TREE_TYPE (e));
1291 return cxx_sizeof_or_alignof_type (e, op, true);
1295 /* Perform the conversions in [expr] that apply when an lvalue appears
1296 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1297 function-to-pointer conversions.
1299 In addition manifest constants are replaced by their values. */
1302 decay_conversion (tree exp)
1305 enum tree_code code;
1307 type = TREE_TYPE (exp);
1308 code = TREE_CODE (type);
1310 if (code == REFERENCE_TYPE)
1312 exp = convert_from_reference (exp);
1313 type = TREE_TYPE (exp);
1314 code = TREE_CODE (type);
1317 if (type == error_mark_node)
1318 return error_mark_node;
1320 if (type_unknown_p (exp))
1322 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1323 return error_mark_node;
1326 /* Constants can be used directly unless they're not loadable. */
1327 if (TREE_CODE (exp) == CONST_DECL)
1328 exp = DECL_INITIAL (exp);
1329 /* Replace a nonvolatile const static variable with its value. We
1330 don't do this for arrays, though; we want the address of the
1331 first element of the array, not the address of the first element
1332 of its initializing constant. */
1333 else if (code != ARRAY_TYPE)
1335 exp = decl_constant_value (exp);
1336 type = TREE_TYPE (exp);
1339 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1340 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1342 if (code == VOID_TYPE)
1344 error ("void value not ignored as it ought to be");
1345 return error_mark_node;
1347 if (code == METHOD_TYPE)
1349 error ("invalid use of non-static member function");
1350 return error_mark_node;
1352 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1353 return build_unary_op (ADDR_EXPR, exp, 0);
1354 if (code == ARRAY_TYPE)
1359 if (TREE_CODE (exp) == INDIRECT_REF)
1360 return build_nop (build_pointer_type (TREE_TYPE (type)),
1361 TREE_OPERAND (exp, 0));
1363 if (TREE_CODE (exp) == COMPOUND_EXPR)
1365 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1366 return build (COMPOUND_EXPR, TREE_TYPE (op1),
1367 TREE_OPERAND (exp, 0), op1);
1371 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1373 error ("invalid use of non-lvalue array");
1374 return error_mark_node;
1377 ptrtype = build_pointer_type (TREE_TYPE (type));
1379 if (TREE_CODE (exp) == VAR_DECL)
1381 if (!cxx_mark_addressable (exp))
1382 return error_mark_node;
1383 adr = build_nop (ptrtype, build_address (exp));
1386 /* This way is better for a COMPONENT_REF since it can
1387 simplify the offset for a component. */
1388 adr = build_unary_op (ADDR_EXPR, exp, 1);
1389 return cp_convert (ptrtype, adr);
1392 /* [basic.lval]: Class rvalues can have cv-qualified types; non-class
1393 rvalues always have cv-unqualified types. */
1394 if (! CLASS_TYPE_P (type))
1395 exp = cp_convert (TYPE_MAIN_VARIANT (type), exp);
1401 default_conversion (tree exp)
1403 exp = decay_conversion (exp);
1405 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1406 exp = perform_integral_promotions (exp);
1411 /* EXPR is an expression with an integral or enumeration type.
1412 Perform the integral promotions in [conv.prom], and return the
1416 perform_integral_promotions (tree expr)
1421 type = TREE_TYPE (expr);
1422 my_friendly_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type), 20030703);
1423 promoted_type = type_promotes_to (type);
1424 if (type != promoted_type)
1425 expr = cp_convert (promoted_type, expr);
1429 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1433 inline_conversion (tree exp)
1435 if (TREE_CODE (exp) == FUNCTION_DECL)
1436 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1441 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1442 decay_conversion to one. */
1445 string_conv_p (tree totype, tree exp, int warn)
1449 if (! flag_const_strings || TREE_CODE (totype) != POINTER_TYPE)
1452 t = TREE_TYPE (totype);
1453 if (!same_type_p (t, char_type_node)
1454 && !same_type_p (t, wchar_type_node))
1457 if (TREE_CODE (exp) == STRING_CST)
1459 /* Make sure that we don't try to convert between char and wchar_t. */
1460 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1465 /* Is this a string constant which has decayed to 'const char *'? */
1466 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1467 if (!same_type_p (TREE_TYPE (exp), t))
1470 if (TREE_CODE (exp) != ADDR_EXPR
1471 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1475 /* This warning is not very useful, as it complains about printf. */
1476 if (warn && warn_write_strings)
1477 warning ("deprecated conversion from string constant to `%T'", totype);
1482 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1483 can, for example, use as an lvalue. This code used to be in
1484 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1485 expressions, where we're dealing with aggregates. But now it's again only
1486 called from unary_complex_lvalue. The case (in particular) that led to
1487 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1491 rationalize_conditional_expr (enum tree_code code, tree t)
1493 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1494 the first operand is always the one to be used if both operands
1495 are equal, so we know what conditional expression this used to be. */
1496 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1499 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1500 ? LE_EXPR : GE_EXPR),
1501 TREE_OPERAND (t, 0),
1502 TREE_OPERAND (t, 1),
1503 /*overloaded_p=*/NULL),
1504 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1505 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1509 build_conditional_expr (TREE_OPERAND (t, 0),
1510 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1511 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1514 /* Given the TYPE of an anonymous union field inside T, return the
1515 FIELD_DECL for the field. If not found return NULL_TREE. Because
1516 anonymous unions can nest, we must also search all anonymous unions
1517 that are directly reachable. */
1520 lookup_anon_field (tree t, tree type)
1524 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1526 if (TREE_STATIC (field))
1528 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1531 /* If we find it directly, return the field. */
1532 if (DECL_NAME (field) == NULL_TREE
1533 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1538 /* Otherwise, it could be nested, search harder. */
1539 if (DECL_NAME (field) == NULL_TREE
1540 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1542 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1550 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1551 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1552 non-NULL, it indicates the path to the base used to name MEMBER.
1553 If PRESERVE_REFERENCE is true, the expression returned will have
1554 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1555 returned will have the type referred to by the reference.
1557 This function does not perform access control; that is either done
1558 earlier by the parser when the name of MEMBER is resolved to MEMBER
1559 itself, or later when overload resolution selects one of the
1560 functions indicated by MEMBER. */
1563 build_class_member_access_expr (tree object, tree member,
1564 tree access_path, bool preserve_reference)
1568 tree result = NULL_TREE;
1570 if (object == error_mark_node || member == error_mark_node)
1571 return error_mark_node;
1573 if (TREE_CODE (member) == PSEUDO_DTOR_EXPR)
1576 my_friendly_assert (DECL_P (member) || BASELINK_P (member),
1581 The type of the first expression shall be "class object" (of a
1583 object_type = TREE_TYPE (object);
1584 if (!currently_open_class (object_type)
1585 && !complete_type_or_else (object_type, object))
1586 return error_mark_node;
1587 if (!CLASS_TYPE_P (object_type))
1589 error ("request for member `%D' in `%E', which is of non-class type `%T'",
1590 member, object, object_type);
1591 return error_mark_node;
1594 /* The standard does not seem to actually say that MEMBER must be a
1595 member of OBJECT_TYPE. However, that is clearly what is
1597 if (DECL_P (member))
1599 member_scope = DECL_CLASS_CONTEXT (member);
1601 if (TREE_DEPRECATED (member))
1602 warn_deprecated_use (member);
1605 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1606 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1607 presently be the anonymous union. Go outwards until we find a
1608 type related to OBJECT_TYPE. */
1609 while (ANON_AGGR_TYPE_P (member_scope)
1610 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1612 member_scope = TYPE_CONTEXT (member_scope);
1613 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1615 if (TREE_CODE (member) == FIELD_DECL)
1616 error ("invalid use of nonstatic data member '%E'", member);
1618 error ("`%D' is not a member of `%T'", member, object_type);
1619 return error_mark_node;
1622 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1623 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1624 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1626 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1628 object = build_indirect_ref (temp, NULL);
1631 /* In [expr.ref], there is an explicit list of the valid choices for
1632 MEMBER. We check for each of those cases here. */
1633 if (TREE_CODE (member) == VAR_DECL)
1635 /* A static data member. */
1637 /* If OBJECT has side-effects, they are supposed to occur. */
1638 if (TREE_SIDE_EFFECTS (object))
1639 result = build (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1641 else if (TREE_CODE (member) == FIELD_DECL)
1643 /* A non-static data member. */
1648 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1649 && integer_zerop (TREE_OPERAND (object, 0)));
1651 /* Convert OBJECT to the type of MEMBER. */
1652 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1653 TYPE_MAIN_VARIANT (member_scope)))
1658 binfo = lookup_base (access_path ? access_path : object_type,
1659 member_scope, ba_ignore, &kind);
1660 if (binfo == error_mark_node)
1661 return error_mark_node;
1663 /* It is invalid to try to get to a virtual base of a
1664 NULL object. The most common cause is invalid use of
1666 if (null_object_p && kind == bk_via_virtual)
1668 error ("invalid access to non-static data member `%D' of NULL object",
1670 error ("(perhaps the `offsetof' macro was used incorrectly)");
1671 return error_mark_node;
1674 /* Convert to the base. */
1675 object = build_base_path (PLUS_EXPR, object, binfo,
1677 /* If we found the base successfully then we should be able
1678 to convert to it successfully. */
1679 my_friendly_assert (object != error_mark_node,
1683 /* Complain about other invalid uses of offsetof, even though they will
1684 give the right answer. Note that we complain whether or not they
1685 actually used the offsetof macro, since there's no way to know at this
1686 point. So we just give a warning, instead of a pedwarn. */
1687 if (null_object_p && warn_invalid_offsetof
1688 && CLASSTYPE_NON_POD_P (object_type))
1690 warning ("invalid access to non-static data member `%D' of NULL object",
1692 warning ("(perhaps the `offsetof' macro was used incorrectly)");
1695 /* If MEMBER is from an anonymous aggregate, we have converted
1696 OBJECT so that it refers to the class containing the
1697 anonymous union. Generate a reference to the anonymous union
1698 itself, and recur to find MEMBER. */
1699 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1700 /* When this code is called from build_field_call, the
1701 object already has the type of the anonymous union.
1702 That is because the COMPONENT_REF was already
1703 constructed, and was then disassembled before calling
1704 build_field_call. After the function-call code is
1705 cleaned up, this waste can be eliminated. */
1706 && (!same_type_ignoring_top_level_qualifiers_p
1707 (TREE_TYPE (object), DECL_CONTEXT (member))))
1709 tree anonymous_union;
1711 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1712 DECL_CONTEXT (member));
1713 object = build_class_member_access_expr (object,
1715 /*access_path=*/NULL_TREE,
1716 preserve_reference);
1719 /* Compute the type of the field, as described in [expr.ref]. */
1720 type_quals = TYPE_UNQUALIFIED;
1721 member_type = TREE_TYPE (member);
1722 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1724 type_quals = (cp_type_quals (member_type)
1725 | cp_type_quals (object_type));
1727 /* A field is const (volatile) if the enclosing object, or the
1728 field itself, is const (volatile). But, a mutable field is
1729 not const, even within a const object. */
1730 if (DECL_MUTABLE_P (member))
1731 type_quals &= ~TYPE_QUAL_CONST;
1732 member_type = cp_build_qualified_type (member_type, type_quals);
1735 result = fold (build (COMPONENT_REF, member_type, object, member));
1737 /* Mark the expression const or volatile, as appropriate. Even
1738 though we've dealt with the type above, we still have to mark the
1739 expression itself. */
1740 if (type_quals & TYPE_QUAL_CONST)
1741 TREE_READONLY (result) = 1;
1742 else if (type_quals & TYPE_QUAL_VOLATILE)
1743 TREE_THIS_VOLATILE (result) = 1;
1745 else if (BASELINK_P (member))
1747 /* The member is a (possibly overloaded) member function. */
1751 /* If the MEMBER is exactly one static member function, then we
1752 know the type of the expression. Otherwise, we must wait
1753 until overload resolution has been performed. */
1754 functions = BASELINK_FUNCTIONS (member);
1755 if (TREE_CODE (functions) == FUNCTION_DECL
1756 && DECL_STATIC_FUNCTION_P (functions))
1757 type = TREE_TYPE (functions);
1759 type = unknown_type_node;
1760 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1761 base. That will happen when the function is called. */
1762 result = build (COMPONENT_REF, type, object, member);
1764 else if (TREE_CODE (member) == CONST_DECL)
1766 /* The member is an enumerator. */
1768 /* If OBJECT has side-effects, they are supposed to occur. */
1769 if (TREE_SIDE_EFFECTS (object))
1770 result = build (COMPOUND_EXPR, TREE_TYPE (result),
1775 error ("invalid use of `%D'", member);
1776 return error_mark_node;
1779 if (!preserve_reference)
1782 If E2 is declared to have type "reference to T", then ... the
1783 type of E1.E2 is T. */
1784 result = convert_from_reference (result);
1789 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1790 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1793 lookup_destructor (tree object, tree scope, tree dtor_name)
1795 tree object_type = TREE_TYPE (object);
1796 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1799 if (scope && !check_dtor_name (scope, dtor_name))
1801 error ("qualified type `%T' does not match destructor name `~%T'",
1803 return error_mark_node;
1805 if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1807 error ("the type being destroyed is `%T', but the destructor refers to `%T'",
1808 TYPE_MAIN_VARIANT (object_type), dtor_type);
1809 return error_mark_node;
1811 if (!TYPE_HAS_DESTRUCTOR (dtor_type))
1812 return build (PSEUDO_DTOR_EXPR, void_type_node, object, scope,
1814 expr = lookup_member (dtor_type, complete_dtor_identifier,
1815 /*protect=*/1, /*want_type=*/false);
1816 expr = (adjust_result_of_qualified_name_lookup
1817 (expr, dtor_type, object_type));
1821 /* This function is called by the parser to process a class member
1822 access expression of the form OBJECT.NAME. NAME is a node used by
1823 the parser to represent a name; it is not yet a DECL. It may,
1824 however, be a BASELINK where the BASELINK_FUNCTIONS is a
1825 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
1826 there is no reason to do the lookup twice, so the parser keeps the
1830 finish_class_member_access_expr (tree object, tree name)
1835 tree access_path = NULL_TREE;
1836 tree orig_object = object;
1837 tree orig_name = name;
1839 if (object == error_mark_node || name == error_mark_node)
1840 return error_mark_node;
1842 object_type = TREE_TYPE (object);
1844 if (processing_template_decl)
1846 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
1847 dependent_type_p (object_type)
1848 /* If NAME is just an IDENTIFIER_NODE, then the expression
1850 || TREE_CODE (object) == IDENTIFIER_NODE
1851 /* If NAME is "f<args>", where either 'f' or 'args' is
1852 dependent, then the expression is dependent. */
1853 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
1854 && dependent_template_id_p (TREE_OPERAND (name, 0),
1855 TREE_OPERAND (name, 1)))
1856 /* If NAME is "T::X" where "T" is dependent, then the
1857 expression is dependent. */
1858 || (TREE_CODE (name) == SCOPE_REF
1859 && TYPE_P (TREE_OPERAND (name, 0))
1860 && dependent_type_p (TREE_OPERAND (name, 0))))
1861 return build_min_nt (COMPONENT_REF, object, name);
1862 object = build_non_dependent_expr (object);
1865 if (TREE_CODE (object_type) == REFERENCE_TYPE)
1867 object = convert_from_reference (object);
1868 object_type = TREE_TYPE (object);
1873 The type of the first expression shall be "class object" (of a
1875 if (!currently_open_class (object_type)
1876 && !complete_type_or_else (object_type, object))
1877 return error_mark_node;
1878 if (!CLASS_TYPE_P (object_type))
1880 error ("request for member `%D' in `%E', which is of non-class type `%T'",
1881 name, object, object_type);
1882 return error_mark_node;
1885 if (BASELINK_P (name))
1887 /* A member function that has already been looked up. */
1888 my_friendly_assert ((TREE_CODE (BASELINK_FUNCTIONS (name))
1889 == TEMPLATE_ID_EXPR),
1895 bool is_template_id = false;
1896 tree template_args = NULL_TREE;
1899 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
1901 is_template_id = true;
1902 template_args = TREE_OPERAND (name, 1);
1903 name = TREE_OPERAND (name, 0);
1905 if (TREE_CODE (name) == OVERLOAD)
1906 name = DECL_NAME (get_first_fn (name));
1907 else if (DECL_P (name))
1908 name = DECL_NAME (name);
1911 if (TREE_CODE (name) == SCOPE_REF)
1913 /* A qualified name. The qualifying class or namespace `S' has
1914 already been looked up; it is either a TYPE or a
1915 NAMESPACE_DECL. The member name is either an IDENTIFIER_NODE
1916 or a BIT_NOT_EXPR. */
1917 scope = TREE_OPERAND (name, 0);
1918 name = TREE_OPERAND (name, 1);
1919 my_friendly_assert ((CLASS_TYPE_P (scope)
1920 || TREE_CODE (scope) == NAMESPACE_DECL),
1922 my_friendly_assert ((TREE_CODE (name) == IDENTIFIER_NODE
1923 || TREE_CODE (name) == BIT_NOT_EXPR),
1926 /* If SCOPE is a namespace, then the qualified name does not
1927 name a member of OBJECT_TYPE. */
1928 if (TREE_CODE (scope) == NAMESPACE_DECL)
1930 error ("`%D::%D' is not a member of `%T'",
1931 scope, name, object_type);
1932 return error_mark_node;
1935 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
1936 access_path = lookup_base (object_type, scope, ba_check, NULL);
1937 if (access_path == error_mark_node)
1938 return error_mark_node;
1941 error ("`%T' is not a base of `%T'", scope, object_type);
1942 return error_mark_node;
1948 access_path = object_type;
1951 if (TREE_CODE (name) == BIT_NOT_EXPR)
1952 member = lookup_destructor (object, scope, name);
1955 /* Look up the member. */
1956 member = lookup_member (access_path, name, /*protect=*/1,
1957 /*want_type=*/false);
1958 if (member == NULL_TREE)
1960 error ("'%D' has no member named '%E'", object_type, name);
1961 return error_mark_node;
1963 if (member == error_mark_node)
1964 return error_mark_node;
1969 tree template = member;
1971 if (BASELINK_P (template))
1972 template = lookup_template_function (template, template_args);
1975 error ("`%D' is not a member template function", name);
1976 return error_mark_node;
1981 if (TREE_DEPRECATED (member))
1982 warn_deprecated_use (member);
1984 expr = build_class_member_access_expr (object, member, access_path,
1985 /*preserve_reference=*/false);
1986 if (processing_template_decl && expr != error_mark_node)
1987 return build_min_non_dep (COMPONENT_REF, expr,
1988 orig_object, orig_name);
1992 /* Return an expression for the MEMBER_NAME field in the internal
1993 representation of PTRMEM, a pointer-to-member function. (Each
1994 pointer-to-member function type gets its own RECORD_TYPE so it is
1995 more convenient to access the fields by name than by FIELD_DECL.)
1996 This routine converts the NAME to a FIELD_DECL and then creates the
1997 node for the complete expression. */
2000 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2006 /* This code is a stripped down version of
2007 build_class_member_access_expr. It does not work to use that
2008 routine directly because it expects the object to be of class
2010 ptrmem_type = TREE_TYPE (ptrmem);
2011 my_friendly_assert (TYPE_PTRMEMFUNC_P (ptrmem_type), 20020804);
2012 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2013 /*want_type=*/false);
2014 member_type = cp_build_qualified_type (TREE_TYPE (member),
2015 cp_type_quals (ptrmem_type));
2016 return fold (build (COMPONENT_REF, member_type, ptrmem, member));
2019 /* Given an expression PTR for a pointer, return an expression
2020 for the value pointed to.
2021 ERRORSTRING is the name of the operator to appear in error messages.
2023 This function may need to overload OPERATOR_FNNAME.
2024 Must also handle REFERENCE_TYPEs for C++. */
2027 build_x_indirect_ref (tree expr, const char *errorstring)
2029 tree orig_expr = expr;
2032 if (processing_template_decl)
2034 if (type_dependent_expression_p (expr))
2035 return build_min_nt (INDIRECT_REF, expr);
2036 expr = build_non_dependent_expr (expr);
2039 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2040 NULL_TREE, /*overloaded_p=*/NULL);
2042 rval = build_indirect_ref (expr, errorstring);
2044 if (processing_template_decl && rval != error_mark_node)
2045 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2051 build_indirect_ref (tree ptr, const char *errorstring)
2055 if (ptr == error_mark_node)
2056 return error_mark_node;
2058 if (ptr == current_class_ptr)
2059 return current_class_ref;
2061 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2062 ? ptr : decay_conversion (ptr));
2063 type = TREE_TYPE (pointer);
2065 if (TYPE_PTR_P (type) || TREE_CODE (type) == REFERENCE_TYPE)
2069 If the type of the expression is "pointer to T," the type
2070 of the result is "T."
2072 We must use the canonical variant because certain parts of
2073 the back end, like fold, do pointer comparisons between
2075 tree t = canonical_type_variant (TREE_TYPE (type));
2077 if (VOID_TYPE_P (t))
2079 /* A pointer to incomplete type (other than cv void) can be
2080 dereferenced [expr.unary.op]/1 */
2081 error ("`%T' is not a pointer-to-object type", type);
2082 return error_mark_node;
2084 else if (TREE_CODE (pointer) == ADDR_EXPR
2085 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2086 /* The POINTER was something like `&x'. We simplify `*&x' to
2088 return TREE_OPERAND (pointer, 0);
2091 tree ref = build1 (INDIRECT_REF, t, pointer);
2093 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2094 so that we get the proper error message if the result is used
2095 to assign to. Also, &* is supposed to be a no-op. */
2096 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2097 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2098 TREE_SIDE_EFFECTS (ref)
2099 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2103 /* `pointer' won't be an error_mark_node if we were given a
2104 pointer to member, so it's cool to check for this here. */
2105 else if (TYPE_PTR_TO_MEMBER_P (type))
2106 error ("invalid use of `%s' on pointer to member", errorstring);
2107 else if (pointer != error_mark_node)
2110 error ("invalid type argument of `%s'", errorstring);
2112 error ("invalid type argument");
2114 return error_mark_node;
2117 /* This handles expressions of the form "a[i]", which denotes
2120 This is logically equivalent in C to *(a+i), but we may do it differently.
2121 If A is a variable or a member, we generate a primitive ARRAY_REF.
2122 This avoids forcing the array out of registers, and can work on
2123 arrays that are not lvalues (for example, members of structures returned
2126 If INDEX is of some user-defined type, it must be converted to
2127 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2128 will inherit the type of the array, which will be some pointer type. */
2131 build_array_ref (tree array, tree idx)
2135 error ("subscript missing in array reference");
2136 return error_mark_node;
2139 if (TREE_TYPE (array) == error_mark_node
2140 || TREE_TYPE (idx) == error_mark_node)
2141 return error_mark_node;
2143 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2145 switch (TREE_CODE (array))
2149 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2150 return build (COMPOUND_EXPR, TREE_TYPE (value),
2151 TREE_OPERAND (array, 0), value);
2155 return build_conditional_expr
2156 (TREE_OPERAND (array, 0),
2157 build_array_ref (TREE_OPERAND (array, 1), idx),
2158 build_array_ref (TREE_OPERAND (array, 2), idx));
2164 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2168 /* Subscripting with type char is likely to lose
2169 on a machine where chars are signed.
2170 So warn on any machine, but optionally.
2171 Don't warn for unsigned char since that type is safe.
2172 Don't warn for signed char because anyone who uses that
2173 must have done so deliberately. */
2174 if (warn_char_subscripts
2175 && TYPE_MAIN_VARIANT (TREE_TYPE (idx)) == char_type_node)
2176 warning ("array subscript has type `char'");
2178 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2180 error ("array subscript is not an integer");
2181 return error_mark_node;
2184 /* Apply integral promotions *after* noticing character types.
2185 (It is unclear why we do these promotions -- the standard
2186 does not say that we should. In fact, the natual thing would
2187 seem to be to convert IDX to ptrdiff_t; we're performing
2188 pointer arithmetic.) */
2189 idx = perform_integral_promotions (idx);
2191 /* An array that is indexed by a non-constant
2192 cannot be stored in a register; we must be able to do
2193 address arithmetic on its address.
2194 Likewise an array of elements of variable size. */
2195 if (TREE_CODE (idx) != INTEGER_CST
2196 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2197 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2200 if (!cxx_mark_addressable (array))
2201 return error_mark_node;
2204 /* An array that is indexed by a constant value which is not within
2205 the array bounds cannot be stored in a register either; because we
2206 would get a crash in store_bit_field/extract_bit_field when trying
2207 to access a non-existent part of the register. */
2208 if (TREE_CODE (idx) == INTEGER_CST
2209 && TYPE_DOMAIN (TREE_TYPE (array))
2210 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2212 if (!cxx_mark_addressable (array))
2213 return error_mark_node;
2216 if (pedantic && !lvalue_p (array))
2217 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2219 /* Note in C++ it is valid to subscript a `register' array, since
2220 it is valid to take the address of something with that
2221 storage specification. */
2225 while (TREE_CODE (foo) == COMPONENT_REF)
2226 foo = TREE_OPERAND (foo, 0);
2227 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2228 warning ("subscripting array declared `register'");
2231 type = TREE_TYPE (TREE_TYPE (array));
2232 rval = build (ARRAY_REF, type, array, idx);
2233 /* Array ref is const/volatile if the array elements are
2234 or if the array is.. */
2235 TREE_READONLY (rval)
2236 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2237 TREE_SIDE_EFFECTS (rval)
2238 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2239 TREE_THIS_VOLATILE (rval)
2240 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2241 return require_complete_type (fold (rval));
2245 tree ar = default_conversion (array);
2246 tree ind = default_conversion (idx);
2248 /* Put the integer in IND to simplify error checking. */
2249 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2256 if (ar == error_mark_node)
2259 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2261 error ("subscripted value is neither array nor pointer");
2262 return error_mark_node;
2264 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2266 error ("array subscript is not an integer");
2267 return error_mark_node;
2270 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2275 /* Resolve a pointer to member function. INSTANCE is the object
2276 instance to use, if the member points to a virtual member.
2278 This used to avoid checking for virtual functions if basetype
2279 has no virtual functions, according to an earlier ANSI draft.
2280 With the final ISO C++ rules, such an optimization is
2281 incorrect: A pointer to a derived member can be static_cast
2282 to pointer-to-base-member, as long as the dynamic object
2283 later has the right member. */
2286 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2288 if (TREE_CODE (function) == OFFSET_REF)
2289 function = TREE_OPERAND (function, 1);
2291 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2293 tree idx, delta, e1, e2, e3, vtbl, basetype;
2294 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2296 tree instance_ptr = *instance_ptrptr;
2297 tree instance_save_expr = 0;
2298 if (instance_ptr == error_mark_node)
2300 if (TREE_CODE (function) == PTRMEM_CST)
2302 /* Extracting the function address from a pmf is only
2303 allowed with -Wno-pmf-conversions. It only works for
2305 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2306 e1 = convert (fntype, e1);
2311 error ("object missing in use of `%E'", function);
2312 return error_mark_node;
2316 if (TREE_SIDE_EFFECTS (instance_ptr))
2317 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2319 if (TREE_SIDE_EFFECTS (function))
2320 function = save_expr (function);
2322 /* Start by extracting all the information from the PMF itself. */
2323 e3 = PFN_FROM_PTRMEMFUNC (function);
2324 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2325 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2326 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2328 case ptrmemfunc_vbit_in_pfn:
2329 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2330 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2333 case ptrmemfunc_vbit_in_delta:
2334 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2335 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2342 /* Convert down to the right base before using the instance. First
2344 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2345 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2346 basetype, ba_check, NULL);
2347 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype, 1);
2348 if (instance_ptr == error_mark_node)
2349 return error_mark_node;
2350 /* ...and then the delta in the PMF. */
2351 instance_ptr = build (PLUS_EXPR, TREE_TYPE (instance_ptr),
2352 instance_ptr, delta);
2354 /* Hand back the adjusted 'this' argument to our caller. */
2355 *instance_ptrptr = instance_ptr;
2357 /* Next extract the vtable pointer from the object. */
2358 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2360 vtbl = build_indirect_ref (vtbl, NULL);
2362 /* Finally, extract the function pointer from the vtable. */
2363 e2 = fold (build (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx));
2364 e2 = build_indirect_ref (e2, NULL);
2365 TREE_CONSTANT (e2) = 1;
2366 TREE_INVARIANT (e2) = 1;
2368 /* When using function descriptors, the address of the
2369 vtable entry is treated as a function pointer. */
2370 if (TARGET_VTABLE_USES_DESCRIPTORS)
2371 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2372 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2374 TREE_TYPE (e2) = TREE_TYPE (e3);
2375 e1 = build_conditional_expr (e1, e2, e3);
2377 /* Make sure this doesn't get evaluated first inside one of the
2378 branches of the COND_EXPR. */
2379 if (instance_save_expr)
2380 e1 = build (COMPOUND_EXPR, TREE_TYPE (e1),
2381 instance_save_expr, e1);
2389 build_function_call (tree function, tree params)
2391 tree fntype, fndecl;
2392 tree coerced_params;
2394 tree name = NULL_TREE;
2396 tree original = function;
2398 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2399 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2400 if (TREE_CODE (function) == NOP_EXPR
2401 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2402 function = TREE_OPERAND (function, 0);
2404 if (TREE_CODE (function) == FUNCTION_DECL)
2406 name = DECL_NAME (function);
2408 mark_used (function);
2411 /* Convert anything with function type to a pointer-to-function. */
2412 if (pedantic && DECL_MAIN_P (function))
2413 pedwarn ("ISO C++ forbids calling `::main' from within program");
2415 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2416 (because calling an inline function does not mean the function
2417 needs to be separately compiled). */
2419 if (DECL_INLINE (function))
2420 function = inline_conversion (function);
2422 function = build_addr_func (function);
2428 function = build_addr_func (function);
2431 if (function == error_mark_node)
2432 return error_mark_node;
2434 fntype = TREE_TYPE (function);
2436 if (TYPE_PTRMEMFUNC_P (fntype))
2438 error ("must use .* or ->* to call pointer-to-member function in `%E (...)'",
2440 return error_mark_node;
2443 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2444 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2446 if (!((TREE_CODE (fntype) == POINTER_TYPE
2447 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2449 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2451 error ("`%E' cannot be used as a function", original);
2452 return error_mark_node;
2455 /* fntype now gets the type of function pointed to. */
2456 fntype = TREE_TYPE (fntype);
2458 /* Convert the parameters to the types declared in the
2459 function prototype, or apply default promotions. */
2461 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2462 params, fndecl, LOOKUP_NORMAL);
2463 if (coerced_params == error_mark_node)
2464 return error_mark_node;
2466 /* Check for errors in format strings. */
2469 check_function_format (NULL, TYPE_ATTRIBUTES (fntype), coerced_params);
2471 /* Recognize certain built-in functions so we can make tree-codes
2472 other than CALL_EXPR. We do this when it enables fold-const.c
2473 to do something useful. */
2475 if (TREE_CODE (function) == ADDR_EXPR
2476 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
2477 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
2479 result = expand_tree_builtin (TREE_OPERAND (function, 0),
2480 params, coerced_params);
2485 return build_cxx_call (function, params, coerced_params);
2488 /* Convert the actual parameter expressions in the list VALUES
2489 to the types in the list TYPELIST.
2490 If parmdecls is exhausted, or when an element has NULL as its type,
2491 perform the default conversions.
2493 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2495 This is also where warnings about wrong number of args are generated.
2497 Return a list of expressions for the parameters as converted.
2499 Both VALUES and the returned value are chains of TREE_LIST nodes
2500 with the elements of the list in the TREE_VALUE slots of those nodes.
2502 In C++, unspecified trailing parameters can be filled in with their
2503 default arguments, if such were specified. Do so here. */
2506 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2508 tree typetail, valtail;
2509 tree result = NULL_TREE;
2510 const char *called_thing = 0;
2513 /* Argument passing is always copy-initialization. */
2514 flags |= LOOKUP_ONLYCONVERTING;
2518 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2520 if (DECL_NAME (fndecl) == NULL_TREE
2521 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2522 called_thing = "constructor";
2524 called_thing = "member function";
2527 called_thing = "function";
2530 for (valtail = values, typetail = typelist;
2532 valtail = TREE_CHAIN (valtail), i++)
2534 tree type = typetail ? TREE_VALUE (typetail) : 0;
2535 tree val = TREE_VALUE (valtail);
2537 if (val == error_mark_node)
2538 return error_mark_node;
2540 if (type == void_type_node)
2544 cp_error_at ("too many arguments to %s `%+#D'", called_thing,
2546 error ("at this point in file");
2549 error ("too many arguments to function");
2550 /* In case anybody wants to know if this argument
2553 TREE_TYPE (tree_last (result)) = error_mark_node;
2557 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2558 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2559 if (TREE_CODE (val) == NOP_EXPR
2560 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2561 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2562 val = TREE_OPERAND (val, 0);
2564 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2566 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2567 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2568 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2569 val = decay_conversion (val);
2572 if (val == error_mark_node)
2573 return error_mark_node;
2577 /* Formal parm type is specified by a function prototype. */
2580 if (!COMPLETE_TYPE_P (complete_type (type)))
2583 error ("parameter %P of `%D' has incomplete type `%T'",
2586 error ("parameter %P has incomplete type `%T'", i, type);
2587 parmval = error_mark_node;
2591 parmval = convert_for_initialization
2592 (NULL_TREE, type, val, flags,
2593 "argument passing", fndecl, i);
2594 parmval = convert_for_arg_passing (type, parmval);
2597 if (parmval == error_mark_node)
2598 return error_mark_node;
2600 result = tree_cons (NULL_TREE, parmval, result);
2604 if (TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE)
2605 val = convert_from_reference (val);
2607 if (fndecl && DECL_BUILT_IN (fndecl)
2608 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2609 /* Don't do ellipsis conversion for __built_in_constant_p
2610 as this will result in spurious warnings for non-POD
2612 val = require_complete_type (val);
2614 val = convert_arg_to_ellipsis (val);
2616 result = tree_cons (NULL_TREE, val, result);
2620 typetail = TREE_CHAIN (typetail);
2623 if (typetail != 0 && typetail != void_list_node)
2625 /* See if there are default arguments that can be used. */
2626 if (TREE_PURPOSE (typetail)
2627 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2629 for (; typetail != void_list_node; ++i)
2632 = convert_default_arg (TREE_VALUE (typetail),
2633 TREE_PURPOSE (typetail),
2636 if (parmval == error_mark_node)
2637 return error_mark_node;
2639 result = tree_cons (0, parmval, result);
2640 typetail = TREE_CHAIN (typetail);
2641 /* ends with `...'. */
2642 if (typetail == NULL_TREE)
2650 cp_error_at ("too few arguments to %s `%+#D'",
2651 called_thing, fndecl);
2652 error ("at this point in file");
2655 error ("too few arguments to function");
2656 return error_mark_list;
2660 return nreverse (result);
2663 /* Build a binary-operation expression, after performing default
2664 conversions on the operands. CODE is the kind of expression to build. */
2667 build_x_binary_op (enum tree_code code, tree arg1, tree arg2,
2677 if (processing_template_decl)
2679 if (type_dependent_expression_p (arg1)
2680 || type_dependent_expression_p (arg2))
2681 return build_min_nt (code, arg1, arg2);
2682 arg1 = build_non_dependent_expr (arg1);
2683 arg2 = build_non_dependent_expr (arg2);
2686 if (code == DOTSTAR_EXPR)
2687 expr = build_m_component_ref (arg1, arg2);
2689 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
2692 if (processing_template_decl && expr != error_mark_node)
2693 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2698 /* Build a binary-operation expression without default conversions.
2699 CODE is the kind of expression to build.
2700 This function differs from `build' in several ways:
2701 the data type of the result is computed and recorded in it,
2702 warnings are generated if arg data types are invalid,
2703 special handling for addition and subtraction of pointers is known,
2704 and some optimization is done (operations on narrow ints
2705 are done in the narrower type when that gives the same result).
2706 Constant folding is also done before the result is returned.
2708 Note that the operands will never have enumeral types
2709 because either they have just had the default conversions performed
2710 or they have both just been converted to some other type in which
2711 the arithmetic is to be done.
2713 C++: must do special pointer arithmetic when implementing
2714 multiple inheritance, and deal with pointer to member functions. */
2717 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2718 int convert_p ATTRIBUTE_UNUSED)
2721 enum tree_code code0, code1;
2724 /* Expression code to give to the expression when it is built.
2725 Normally this is CODE, which is what the caller asked for,
2726 but in some special cases we change it. */
2727 enum tree_code resultcode = code;
2729 /* Data type in which the computation is to be performed.
2730 In the simplest cases this is the common type of the arguments. */
2731 tree result_type = NULL;
2733 /* Nonzero means operands have already been type-converted
2734 in whatever way is necessary.
2735 Zero means they need to be converted to RESULT_TYPE. */
2738 /* Nonzero means create the expression with this type, rather than
2740 tree build_type = 0;
2742 /* Nonzero means after finally constructing the expression
2743 convert it to this type. */
2744 tree final_type = 0;
2746 /* Nonzero if this is an operation like MIN or MAX which can
2747 safely be computed in short if both args are promoted shorts.
2748 Also implies COMMON.
2749 -1 indicates a bitwise operation; this makes a difference
2750 in the exact conditions for when it is safe to do the operation
2751 in a narrower mode. */
2754 /* Nonzero if this is a comparison operation;
2755 if both args are promoted shorts, compare the original shorts.
2756 Also implies COMMON. */
2757 int short_compare = 0;
2759 /* Nonzero if this is a right-shift operation, which can be computed on the
2760 original short and then promoted if the operand is a promoted short. */
2761 int short_shift = 0;
2763 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2766 /* Apply default conversions. */
2770 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2771 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2772 || code == TRUTH_XOR_EXPR)
2774 if (!really_overloaded_fn (op0))
2775 op0 = decay_conversion (op0);
2776 if (!really_overloaded_fn (op1))
2777 op1 = decay_conversion (op1);
2781 if (!really_overloaded_fn (op0))
2782 op0 = default_conversion (op0);
2783 if (!really_overloaded_fn (op1))
2784 op1 = default_conversion (op1);
2787 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2788 STRIP_TYPE_NOPS (op0);
2789 STRIP_TYPE_NOPS (op1);
2791 /* DTRT if one side is an overloaded function, but complain about it. */
2792 if (type_unknown_p (op0))
2794 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
2795 if (t != error_mark_node)
2797 pedwarn ("assuming cast to type `%T' from overloaded function",
2802 if (type_unknown_p (op1))
2804 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
2805 if (t != error_mark_node)
2807 pedwarn ("assuming cast to type `%T' from overloaded function",
2813 type0 = TREE_TYPE (op0);
2814 type1 = TREE_TYPE (op1);
2816 /* The expression codes of the data types of the arguments tell us
2817 whether the arguments are integers, floating, pointers, etc. */
2818 code0 = TREE_CODE (type0);
2819 code1 = TREE_CODE (type1);
2821 /* If an error was already reported for one of the arguments,
2822 avoid reporting another error. */
2824 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
2825 return error_mark_node;
2830 /* Handle the pointer + int case. */
2831 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2832 return cp_pointer_int_sum (PLUS_EXPR, op0, op1);
2833 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
2834 return cp_pointer_int_sum (PLUS_EXPR, op1, op0);
2840 /* Subtraction of two similar pointers.
2841 We must subtract them as integers, then divide by object size. */
2842 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
2843 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
2845 return pointer_diff (op0, op1, common_type (type0, type1));
2846 /* Handle pointer minus int. Just like pointer plus int. */
2847 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2848 return cp_pointer_int_sum (MINUS_EXPR, op0, op1);
2857 case TRUNC_DIV_EXPR:
2859 case FLOOR_DIV_EXPR:
2860 case ROUND_DIV_EXPR:
2861 case EXACT_DIV_EXPR:
2862 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2863 || code0 == COMPLEX_TYPE)
2864 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2865 || code1 == COMPLEX_TYPE))
2867 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
2868 warning ("division by zero in `%E / 0'", op0);
2869 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
2870 warning ("division by zero in `%E / 0.'", op0);
2872 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
2873 resultcode = RDIV_EXPR;
2875 /* When dividing two signed integers, we have to promote to int.
2876 unless we divide by a constant != -1. Note that default
2877 conversion will have been performed on the operands at this
2878 point, so we have to dig out the original type to find out if
2880 shorten = ((TREE_CODE (op0) == NOP_EXPR
2881 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2882 || (TREE_CODE (op1) == INTEGER_CST
2883 && ! integer_all_onesp (op1)));
2892 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2896 case TRUNC_MOD_EXPR:
2897 case FLOOR_MOD_EXPR:
2898 if (code1 == INTEGER_TYPE && integer_zerop (op1))
2899 warning ("division by zero in `%E %% 0'", op0);
2900 else if (code1 == REAL_TYPE && real_zerop (op1))
2901 warning ("division by zero in `%E %% 0.'", op0);
2903 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2905 /* Although it would be tempting to shorten always here, that loses
2906 on some targets, since the modulo instruction is undefined if the
2907 quotient can't be represented in the computation mode. We shorten
2908 only if unsigned or if dividing by something we know != -1. */
2909 shorten = ((TREE_CODE (op0) == NOP_EXPR
2910 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2911 || (TREE_CODE (op1) == INTEGER_CST
2912 && ! integer_all_onesp (op1)));
2917 case TRUTH_ANDIF_EXPR:
2918 case TRUTH_ORIF_EXPR:
2919 case TRUTH_AND_EXPR:
2921 result_type = boolean_type_node;
2924 /* Shift operations: result has same type as first operand;
2925 always convert second operand to int.
2926 Also set SHORT_SHIFT if shifting rightward. */
2929 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2931 result_type = type0;
2932 if (TREE_CODE (op1) == INTEGER_CST)
2934 if (tree_int_cst_lt (op1, integer_zero_node))
2935 warning ("right shift count is negative");
2938 if (! integer_zerop (op1))
2940 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2941 warning ("right shift count >= width of type");
2944 /* Convert the shift-count to an integer, regardless of
2945 size of value being shifted. */
2946 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2947 op1 = cp_convert (integer_type_node, op1);
2948 /* Avoid converting op1 to result_type later. */
2954 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2956 result_type = type0;
2957 if (TREE_CODE (op1) == INTEGER_CST)
2959 if (tree_int_cst_lt (op1, integer_zero_node))
2960 warning ("left shift count is negative");
2961 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2962 warning ("left shift count >= width of type");
2964 /* Convert the shift-count to an integer, regardless of
2965 size of value being shifted. */
2966 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2967 op1 = cp_convert (integer_type_node, op1);
2968 /* Avoid converting op1 to result_type later. */
2975 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2977 result_type = type0;
2978 if (TREE_CODE (op1) == INTEGER_CST)
2980 if (tree_int_cst_lt (op1, integer_zero_node))
2981 warning ("%s rotate count is negative",
2982 (code == LROTATE_EXPR) ? "left" : "right");
2983 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2984 warning ("%s rotate count >= width of type",
2985 (code == LROTATE_EXPR) ? "left" : "right");
2987 /* Convert the shift-count to an integer, regardless of
2988 size of value being shifted. */
2989 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2990 op1 = cp_convert (integer_type_node, op1);
2996 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
2997 warning ("comparing floating point with == or != is unsafe");
2999 build_type = boolean_type_node;
3000 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3001 || code0 == COMPLEX_TYPE)
3002 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3003 || code1 == COMPLEX_TYPE))
3005 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3006 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3007 result_type = composite_pointer_type (type0, type1, op0, op1,
3009 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3010 && null_ptr_cst_p (op1))
3011 result_type = type0;
3012 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3013 && null_ptr_cst_p (op0))
3014 result_type = type1;
3015 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3017 result_type = type0;
3018 error ("ISO C++ forbids comparison between pointer and integer");
3020 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3022 result_type = type1;
3023 error ("ISO C++ forbids comparison between pointer and integer");
3025 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3027 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3028 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3029 result_type = TREE_TYPE (op0);
3031 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3032 return cp_build_binary_op (code, op1, op0);
3033 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
3034 && same_type_p (type0, type1))
3036 /* E will be the final comparison. */
3038 /* E1 and E2 are for scratch. */
3046 if (TREE_SIDE_EFFECTS (op0))
3047 op0 = save_expr (op0);
3048 if (TREE_SIDE_EFFECTS (op1))
3049 op1 = save_expr (op1);
3054 && (!op0.pfn || op0.delta == op1.delta))
3056 The reason for the `!op0.pfn' bit is that a NULL
3057 pointer-to-member is any member with a zero PFN; the
3058 DELTA field is unspecified. */
3059 pfn0 = pfn_from_ptrmemfunc (op0);
3060 pfn1 = pfn_from_ptrmemfunc (op1);
3061 delta0 = build_ptrmemfunc_access_expr (op0,
3063 delta1 = build_ptrmemfunc_access_expr (op1,
3065 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3066 e2 = cp_build_binary_op (EQ_EXPR,
3068 cp_convert (TREE_TYPE (pfn0),
3069 integer_zero_node));
3070 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3071 e2 = build (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3072 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3073 if (code == EQ_EXPR)
3075 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3077 else if ((TYPE_PTRMEMFUNC_P (type0)
3078 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0), type1))
3079 || (TYPE_PTRMEMFUNC_P (type1)
3080 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1), type0)))
3086 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3087 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3089 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3090 result_type = composite_pointer_type (type0, type1, op0, op1,
3098 build_type = boolean_type_node;
3099 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3100 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3102 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3103 result_type = composite_pointer_type (type0, type1, op0, op1,
3105 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3106 && integer_zerop (op1))
3107 result_type = type0;
3108 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3109 && integer_zerop (op0))
3110 result_type = type1;
3111 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3113 result_type = type0;
3114 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3116 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3118 result_type = type1;
3119 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3123 case UNORDERED_EXPR:
3130 build_type = integer_type_node;
3131 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3133 error ("unordered comparison on non-floating point argument");
3134 return error_mark_node;
3143 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3145 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
3147 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3149 if (shorten || common || short_compare)
3150 result_type = common_type (type0, type1);
3152 /* For certain operations (which identify themselves by shorten != 0)
3153 if both args were extended from the same smaller type,
3154 do the arithmetic in that type and then extend.
3156 shorten !=0 and !=1 indicates a bitwise operation.
3157 For them, this optimization is safe only if
3158 both args are zero-extended or both are sign-extended.
3159 Otherwise, we might change the result.
3160 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3161 but calculated in (unsigned short) it would be (unsigned short)-1. */
3163 if (shorten && none_complex)
3165 int unsigned0, unsigned1;
3166 tree arg0 = get_narrower (op0, &unsigned0);
3167 tree arg1 = get_narrower (op1, &unsigned1);
3168 /* UNS is 1 if the operation to be done is an unsigned one. */
3169 int uns = TYPE_UNSIGNED (result_type);
3172 final_type = result_type;
3174 /* Handle the case that OP0 does not *contain* a conversion
3175 but it *requires* conversion to FINAL_TYPE. */
3177 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3178 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
3179 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3180 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
3182 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3184 /* For bitwise operations, signedness of nominal type
3185 does not matter. Consider only how operands were extended. */
3189 /* Note that in all three cases below we refrain from optimizing
3190 an unsigned operation on sign-extended args.
3191 That would not be valid. */
3193 /* Both args variable: if both extended in same way
3194 from same width, do it in that width.
3195 Do it unsigned if args were zero-extended. */
3196 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3197 < TYPE_PRECISION (result_type))
3198 && (TYPE_PRECISION (TREE_TYPE (arg1))
3199 == TYPE_PRECISION (TREE_TYPE (arg0)))
3200 && unsigned0 == unsigned1
3201 && (unsigned0 || !uns))
3202 result_type = c_common_signed_or_unsigned_type
3203 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3204 else if (TREE_CODE (arg0) == INTEGER_CST
3205 && (unsigned1 || !uns)
3206 && (TYPE_PRECISION (TREE_TYPE (arg1))
3207 < TYPE_PRECISION (result_type))
3208 && (type = c_common_signed_or_unsigned_type
3209 (unsigned1, TREE_TYPE (arg1)),
3210 int_fits_type_p (arg0, type)))
3212 else if (TREE_CODE (arg1) == INTEGER_CST
3213 && (unsigned0 || !uns)
3214 && (TYPE_PRECISION (TREE_TYPE (arg0))
3215 < TYPE_PRECISION (result_type))
3216 && (type = c_common_signed_or_unsigned_type
3217 (unsigned0, TREE_TYPE (arg0)),
3218 int_fits_type_p (arg1, type)))
3222 /* Shifts can be shortened if shifting right. */
3227 tree arg0 = get_narrower (op0, &unsigned_arg);
3229 final_type = result_type;
3231 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3232 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
3234 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3235 /* We can shorten only if the shift count is less than the
3236 number of bits in the smaller type size. */
3237 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3238 /* If arg is sign-extended and then unsigned-shifted,
3239 we can simulate this with a signed shift in arg's type
3240 only if the extended result is at least twice as wide
3241 as the arg. Otherwise, the shift could use up all the
3242 ones made by sign-extension and bring in zeros.
3243 We can't optimize that case at all, but in most machines
3244 it never happens because available widths are 2**N. */
3245 && (!TYPE_UNSIGNED (final_type)
3247 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3248 <= TYPE_PRECISION (result_type))))
3250 /* Do an unsigned shift if the operand was zero-extended. */
3252 = c_common_signed_or_unsigned_type (unsigned_arg,
3254 /* Convert value-to-be-shifted to that type. */
3255 if (TREE_TYPE (op0) != result_type)
3256 op0 = cp_convert (result_type, op0);
3261 /* Comparison operations are shortened too but differently.
3262 They identify themselves by setting short_compare = 1. */
3266 /* Don't write &op0, etc., because that would prevent op0
3267 from being kept in a register.
3268 Instead, make copies of the our local variables and
3269 pass the copies by reference, then copy them back afterward. */
3270 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3271 enum tree_code xresultcode = resultcode;
3273 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3275 return cp_convert (boolean_type_node, val);
3276 op0 = xop0, op1 = xop1;
3278 resultcode = xresultcode;
3281 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3282 && warn_sign_compare
3283 /* Do not warn until the template is instantiated; we cannot
3284 bound the ranges of the arguments until that point. */
3285 && !processing_template_decl)
3287 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
3288 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3290 int unsignedp0, unsignedp1;
3291 tree primop0 = get_narrower (op0, &unsignedp0);
3292 tree primop1 = get_narrower (op1, &unsignedp1);
3294 /* Check for comparison of different enum types. */
3295 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3296 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3297 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3298 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3300 warning ("comparison between types `%#T' and `%#T'",
3301 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3304 /* Give warnings for comparisons between signed and unsigned
3305 quantities that may fail. */
3306 /* Do the checking based on the original operand trees, so that
3307 casts will be considered, but default promotions won't be. */
3309 /* Do not warn if the comparison is being done in a signed type,
3310 since the signed type will only be chosen if it can represent
3311 all the values of the unsigned type. */
3312 if (!TYPE_UNSIGNED (result_type))
3314 /* Do not warn if both operands are unsigned. */
3315 else if (op0_signed == op1_signed)
3317 /* Do not warn if the signed quantity is an unsuffixed
3318 integer literal (or some static constant expression
3319 involving such literals or a conditional expression
3320 involving such literals) and it is non-negative. */
3321 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3322 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3324 /* Do not warn if the comparison is an equality operation,
3325 the unsigned quantity is an integral constant and it does
3326 not use the most significant bit of result_type. */
3327 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3328 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3329 && int_fits_type_p (orig_op1, c_common_signed_type
3331 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3332 && int_fits_type_p (orig_op0, c_common_signed_type
3336 warning ("comparison between signed and unsigned integer expressions");
3338 /* Warn if two unsigned values are being compared in a size
3339 larger than their original size, and one (and only one) is the
3340 result of a `~' operator. This comparison will always fail.
3342 Also warn if one operand is a constant, and the constant does not
3343 have all bits set that are set in the ~ operand when it is
3346 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3347 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3349 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3350 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3351 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3352 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3354 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3357 HOST_WIDE_INT constant, mask;
3361 if (host_integerp (primop0, 0))
3364 unsignedp = unsignedp1;
3365 constant = tree_low_cst (primop0, 0);
3370 unsignedp = unsignedp0;
3371 constant = tree_low_cst (primop1, 0);
3374 bits = TYPE_PRECISION (TREE_TYPE (primop));
3375 if (bits < TYPE_PRECISION (result_type)
3376 && bits < HOST_BITS_PER_LONG && unsignedp)
3378 mask = (~ (HOST_WIDE_INT) 0) << bits;
3379 if ((mask & constant) != mask)
3380 warning ("comparison of promoted ~unsigned with constant");
3383 else if (unsignedp0 && unsignedp1
3384 && (TYPE_PRECISION (TREE_TYPE (primop0))
3385 < TYPE_PRECISION (result_type))
3386 && (TYPE_PRECISION (TREE_TYPE (primop1))
3387 < TYPE_PRECISION (result_type)))
3388 warning ("comparison of promoted ~unsigned with unsigned");
3393 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
3394 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3395 Then the expression will be built.
3396 It will be given type FINAL_TYPE if that is nonzero;
3397 otherwise, it will be given type RESULT_TYPE. */
3401 error ("invalid operands of types `%T' and `%T' to binary `%O'",
3402 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3403 return error_mark_node;
3406 /* Issue warnings about peculiar, but valid, uses of NULL. */
3407 if (/* It's reasonable to use pointer values as operands of &&
3408 and ||, so NULL is no exception. */
3409 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3410 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3411 (orig_op0 == null_node
3412 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3413 /* Or vice versa. */
3414 || (orig_op1 == null_node
3415 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3416 /* Or, both are NULL and the operation was not a comparison. */
3417 || (orig_op0 == null_node && orig_op1 == null_node
3418 && code != EQ_EXPR && code != NE_EXPR)))
3419 /* Some sort of arithmetic operation involving NULL was
3420 performed. Note that pointer-difference and pointer-addition
3421 have already been handled above, and so we don't end up here in
3423 warning ("NULL used in arithmetic");
3427 if (TREE_TYPE (op0) != result_type)
3428 op0 = cp_convert (result_type, op0);
3429 if (TREE_TYPE (op1) != result_type)
3430 op1 = cp_convert (result_type, op1);
3432 if (op0 == error_mark_node || op1 == error_mark_node)
3433 return error_mark_node;
3436 if (build_type == NULL_TREE)
3437 build_type = result_type;
3440 tree result = fold (build (resultcode, build_type, op0, op1));
3441 if (final_type != 0)
3442 result = cp_convert (final_type, result);
3447 /* Return a tree for the sum or difference (RESULTCODE says which)
3448 of pointer PTROP and integer INTOP. */
3451 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3453 tree res_type = TREE_TYPE (ptrop);
3455 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3456 in certain circumstance (when it's valid to do so). So we need
3457 to make sure it's complete. We don't need to check here, if we
3458 can actually complete it at all, as those checks will be done in
3459 pointer_int_sum() anyway. */
3460 complete_type (TREE_TYPE (res_type));
3462 return pointer_int_sum (resultcode, ptrop, fold (intop));
3465 /* Return a tree for the difference of pointers OP0 and OP1.
3466 The resulting tree has type int. */
3469 pointer_diff (tree op0, tree op1, tree ptrtype)
3472 tree restype = ptrdiff_type_node;
3473 tree target_type = TREE_TYPE (ptrtype);
3475 if (!complete_type_or_else (target_type, NULL_TREE))
3476 return error_mark_node;
3478 if (pedantic || warn_pointer_arith)
3480 if (TREE_CODE (target_type) == VOID_TYPE)
3481 pedwarn ("ISO C++ forbids using pointer of type `void *' in subtraction");
3482 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3483 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3484 if (TREE_CODE (target_type) == METHOD_TYPE)
3485 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3488 /* First do the subtraction as integers;
3489 then drop through to build the divide operator. */
3491 op0 = cp_build_binary_op (MINUS_EXPR,
3492 cp_convert (restype, op0),
3493 cp_convert (restype, op1));
3495 /* This generates an error if op1 is a pointer to an incomplete type. */
3496 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3497 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3499 op1 = (TYPE_PTROB_P (ptrtype)
3500 ? size_in_bytes (target_type)
3501 : integer_one_node);
3503 /* Do the division. */
3505 result = build (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3506 return fold (result);
3509 /* Construct and perhaps optimize a tree representation
3510 for a unary operation. CODE, a tree_code, specifies the operation
3511 and XARG is the operand. */
3514 build_x_unary_op (enum tree_code code, tree xarg)
3516 tree orig_expr = xarg;
3520 if (processing_template_decl)
3522 if (type_dependent_expression_p (xarg))
3523 return build_min_nt (code, xarg, NULL_TREE);
3524 xarg = build_non_dependent_expr (xarg);
3529 /* [expr.unary.op] says:
3531 The address of an object of incomplete type can be taken.
3533 (And is just the ordinary address operator, not an overloaded
3534 "operator &".) However, if the type is a template
3535 specialization, we must complete the type at this point so that
3536 an overloaded "operator &" will be available if required. */
3537 if (code == ADDR_EXPR
3538 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3539 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
3540 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
3541 || (TREE_CODE (xarg) == OFFSET_REF)))
3542 /* Don't look for a function. */;
3544 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
3545 /*overloaded_p=*/NULL);
3546 if (!exp && code == ADDR_EXPR)
3548 /* A pointer to member-function can be formed only by saying
3550 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3551 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3553 if (TREE_CODE (xarg) != OFFSET_REF)
3555 error ("invalid use of '%E' to form a pointer-to-member-function. Use a qualified-id.",
3557 return error_mark_node;
3561 error ("parenthesis around '%E' cannot be used to form a pointer-to-member-function",
3563 PTRMEM_OK_P (xarg) = 1;
3567 if (TREE_CODE (xarg) == OFFSET_REF)
3569 ptrmem = PTRMEM_OK_P (xarg);
3571 if (!ptrmem && !flag_ms_extensions
3572 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3574 /* A single non-static member, make sure we don't allow a
3575 pointer-to-member. */
3576 xarg = build (OFFSET_REF, TREE_TYPE (xarg),
3577 TREE_OPERAND (xarg, 0),
3578 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3579 PTRMEM_OK_P (xarg) = ptrmem;
3582 else if (TREE_CODE (xarg) == TARGET_EXPR)
3583 warning ("taking address of temporary");
3584 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3585 if (TREE_CODE (exp) == ADDR_EXPR)
3586 PTRMEM_OK_P (exp) = ptrmem;
3589 if (processing_template_decl && exp != error_mark_node)
3590 return build_min_non_dep (code, exp, orig_expr,
3591 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3595 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3596 constants, where a null value is represented by an INTEGER_CST of
3600 cp_truthvalue_conversion (tree expr)
3602 tree type = TREE_TYPE (expr);
3603 if (TYPE_PTRMEM_P (type))
3604 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3606 return c_common_truthvalue_conversion (expr);
3609 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3612 condition_conversion (tree expr)
3615 if (processing_template_decl)
3617 t = perform_implicit_conversion (boolean_type_node, expr);
3618 t = fold (build1 (CLEANUP_POINT_EXPR, boolean_type_node, t));
3622 /* Return an ADDR_EXPR giving the address of T. This function
3623 attempts no optimizations or simplifications; it is a low-level
3627 build_address (tree t)
3631 if (error_operand_p (t) || !cxx_mark_addressable (t))
3632 return error_mark_node;
3634 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3639 /* Return a NOP_EXPR converting EXPR to TYPE. */
3642 build_nop (tree type, tree expr)
3644 if (type == error_mark_node || error_operand_p (expr))
3646 return build1 (NOP_EXPR, type, expr);
3649 /* C++: Must handle pointers to members.
3651 Perhaps type instantiation should be extended to handle conversion
3652 from aggregates to types we don't yet know we want? (Or are those
3653 cases typically errors which should be reported?)
3655 NOCONVERT nonzero suppresses the default promotions
3656 (such as from short to int). */
3659 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3661 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3664 const char *errstring = NULL;
3667 if (arg == error_mark_node)
3668 return error_mark_node;
3673 /* This is used for unary plus, because a CONVERT_EXPR
3674 is enough to prevent anybody from looking inside for
3675 associativity, but won't generate any code. */
3676 if (!(arg = build_expr_type_conversion
3677 (WANT_ARITH | WANT_ENUM | WANT_POINTER, arg, true)))
3678 errstring = "wrong type argument to unary plus";
3682 arg = default_conversion (arg);
3683 arg = build1 (NON_LVALUE_EXPR, TREE_TYPE (arg), arg);
3688 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3689 errstring = "wrong type argument to unary minus";
3690 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3691 arg = perform_integral_promotions (arg);
3695 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3699 arg = default_conversion (arg);
3701 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
3703 errstring = "wrong type argument to bit-complement";
3704 else if (!noconvert)
3705 arg = perform_integral_promotions (arg);
3709 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3710 errstring = "wrong type argument to abs";
3711 else if (!noconvert)
3712 arg = default_conversion (arg);
3716 /* Conjugating a real value is a no-op, but allow it anyway. */
3717 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3718 errstring = "wrong type argument to conjugation";
3719 else if (!noconvert)
3720 arg = default_conversion (arg);
3723 case TRUTH_NOT_EXPR:
3724 arg = perform_implicit_conversion (boolean_type_node, arg);
3725 val = invert_truthvalue (arg);
3726 if (arg != error_mark_node)
3728 errstring = "in argument to unary !";
3735 if (TREE_CODE (arg) == COMPLEX_CST)
3736 return TREE_REALPART (arg);
3737 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3738 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3743 if (TREE_CODE (arg) == COMPLEX_CST)
3744 return TREE_IMAGPART (arg);
3745 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3746 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3748 return cp_convert (TREE_TYPE (arg), integer_zero_node);
3750 case PREINCREMENT_EXPR:
3751 case POSTINCREMENT_EXPR:
3752 case PREDECREMENT_EXPR:
3753 case POSTDECREMENT_EXPR:
3754 /* Handle complex lvalues (when permitted)
3755 by reduction to simpler cases. */
3757 val = unary_complex_lvalue (code, arg);
3761 /* Increment or decrement the real part of the value,
3762 and don't change the imaginary part. */
3763 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3767 arg = stabilize_reference (arg);
3768 real = build_unary_op (REALPART_EXPR, arg, 1);
3769 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
3770 return build (COMPLEX_EXPR, TREE_TYPE (arg),
3771 build_unary_op (code, real, 1), imag);
3774 /* Report invalid types. */
3776 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
3779 if (code == PREINCREMENT_EXPR)
3780 errstring ="no pre-increment operator for type";
3781 else if (code == POSTINCREMENT_EXPR)
3782 errstring ="no post-increment operator for type";
3783 else if (code == PREDECREMENT_EXPR)
3784 errstring ="no pre-decrement operator for type";
3786 errstring ="no post-decrement operator for type";
3790 /* Report something read-only. */
3792 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
3793 || TREE_READONLY (arg))
3794 readonly_error (arg, ((code == PREINCREMENT_EXPR
3795 || code == POSTINCREMENT_EXPR)
3796 ? "increment" : "decrement"),
3801 tree result_type = TREE_TYPE (arg);
3803 arg = get_unwidened (arg, 0);
3804 argtype = TREE_TYPE (arg);
3806 /* ARM $5.2.5 last annotation says this should be forbidden. */
3807 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
3808 pedwarn ("ISO C++ forbids %sing an enum",
3809 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3810 ? "increment" : "decrement");
3812 /* Compute the increment. */
3814 if (TREE_CODE (argtype) == POINTER_TYPE)
3816 tree type = complete_type (TREE_TYPE (argtype));
3818 if (!COMPLETE_OR_VOID_TYPE_P (type))
3819 error ("cannot %s a pointer to incomplete type `%T'",
3820 ((code == PREINCREMENT_EXPR
3821 || code == POSTINCREMENT_EXPR)
3822 ? "increment" : "decrement"), TREE_TYPE (argtype));
3823 else if ((pedantic || warn_pointer_arith)
3824 && !TYPE_PTROB_P (argtype))
3825 pedwarn ("ISO C++ forbids %sing a pointer of type `%T'",
3826 ((code == PREINCREMENT_EXPR
3827 || code == POSTINCREMENT_EXPR)
3828 ? "increment" : "decrement"), argtype);
3829 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
3832 inc = integer_one_node;
3834 inc = cp_convert (argtype, inc);
3836 /* Handle incrementing a cast-expression. */
3838 switch (TREE_CODE (arg))
3843 case FIX_TRUNC_EXPR:
3844 case FIX_FLOOR_EXPR:
3845 case FIX_ROUND_EXPR:
3848 tree incremented, modify, value, compound;
3849 if (! lvalue_p (arg) && pedantic)
3850 pedwarn ("cast to non-reference type used as lvalue");
3851 arg = stabilize_reference (arg);
3852 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
3855 value = save_expr (arg);
3856 incremented = build (((code == PREINCREMENT_EXPR
3857 || code == POSTINCREMENT_EXPR)
3858 ? PLUS_EXPR : MINUS_EXPR),
3859 argtype, value, inc);
3861 modify = build_modify_expr (arg, NOP_EXPR, incremented);
3862 compound = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
3864 /* Eliminate warning about unused result of + or -. */
3865 TREE_NO_WARNING (compound) = 1;
3873 /* Complain about anything else that is not a true lvalue. */
3874 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
3875 || code == POSTINCREMENT_EXPR)
3876 ? "increment" : "decrement")))
3877 return error_mark_node;
3879 /* Forbid using -- on `bool'. */
3880 if (TREE_TYPE (arg) == boolean_type_node)
3882 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
3884 error ("invalid use of `--' on bool variable `%D'", arg);
3885 return error_mark_node;
3887 val = boolean_increment (code, arg);
3890 val = build (code, TREE_TYPE (arg), arg, inc);
3892 TREE_SIDE_EFFECTS (val) = 1;
3893 return cp_convert (result_type, val);
3897 /* Note that this operation never does default_conversion
3898 regardless of NOCONVERT. */
3900 argtype = lvalue_type (arg);
3902 if (TREE_CODE (arg) == OFFSET_REF)
3905 if (TREE_CODE (argtype) == REFERENCE_TYPE)
3907 tree type = build_pointer_type (TREE_TYPE (argtype));
3908 arg = build1 (CONVERT_EXPR, type, arg);
3911 else if (pedantic && DECL_MAIN_P (arg))
3913 pedwarn ("ISO C++ forbids taking address of function `::main'");
3915 /* Let &* cancel out to simplify resulting code. */
3916 if (TREE_CODE (arg) == INDIRECT_REF)
3918 /* We don't need to have `current_class_ptr' wrapped in a
3919 NON_LVALUE_EXPR node. */
3920 if (arg == current_class_ref)
3921 return current_class_ptr;
3923 arg = TREE_OPERAND (arg, 0);
3924 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
3926 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
3927 arg = build1 (CONVERT_EXPR, type, arg);
3929 else if (lvalue_p (arg))
3930 /* Don't let this be an lvalue. */
3931 return non_lvalue (arg);
3935 /* For &x[y], return x+y. But, in a template, ARG may be an
3936 ARRAY_REF representing a non-dependent expression. In that
3937 case, there may be an overloaded "operator []" that will be
3938 chosen at instantiation time; we must not try to optimize
3940 if (TREE_CODE (arg) == ARRAY_REF && !processing_template_decl)
3942 if (!cxx_mark_addressable (TREE_OPERAND (arg, 0)))
3943 return error_mark_node;
3944 return cp_build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
3945 TREE_OPERAND (arg, 1));
3948 /* Uninstantiated types are all functions. Taking the
3949 address of a function is a no-op, so just return the
3952 if (TREE_CODE (arg) == IDENTIFIER_NODE
3953 && IDENTIFIER_OPNAME_P (arg))
3956 /* We don't know the type yet, so just work around the problem.
3957 We know that this will resolve to an lvalue. */
3958 return build1 (ADDR_EXPR, unknown_type_node, arg);
3961 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
3962 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
3964 /* They're trying to take the address of a unique non-static
3965 member function. This is ill-formed (except in MS-land),
3966 but let's try to DTRT.
3967 Note: We only handle unique functions here because we don't
3968 want to complain if there's a static overload; non-unique
3969 cases will be handled by instantiate_type. But we need to
3970 handle this case here to allow casts on the resulting PMF.
3971 We could defer this in non-MS mode, but it's easier to give
3972 a useful error here. */
3974 /* Inside constant member functions, the `this' pointer
3975 contains an extra const qualifier. TYPE_MAIN_VARIANT
3976 is used here to remove this const from the diagnostics
3977 and the created OFFSET_REF. */
3978 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
3979 tree name = DECL_NAME (get_first_fn (TREE_OPERAND (arg, 1)));
3981 if (! flag_ms_extensions)
3983 if (current_class_type
3984 && TREE_OPERAND (arg, 0) == current_class_ref)
3985 /* An expression like &memfn. */
3986 pedwarn ("ISO C++ forbids taking the address of an unqualified"
3987 " or parenthesized non-static member function to form"
3988 " a pointer to member function. Say `&%T::%D'",
3991 pedwarn ("ISO C++ forbids taking the address of a bound member"
3992 " function to form a pointer to member function."
3996 arg = build_offset_ref (base, name, /*address_p=*/true);
4000 if (type_unknown_p (arg))
4001 return build1 (ADDR_EXPR, unknown_type_node, arg);
4003 /* Handle complex lvalues (when permitted)
4004 by reduction to simpler cases. */
4005 val = unary_complex_lvalue (code, arg);
4009 switch (TREE_CODE (arg))
4014 case FIX_TRUNC_EXPR:
4015 case FIX_FLOOR_EXPR:
4016 case FIX_ROUND_EXPR:
4018 if (! lvalue_p (arg) && pedantic)
4019 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4023 arg = OVL_CURRENT (arg);
4030 /* Allow the address of a constructor if all the elements
4032 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_HAS_CONSTRUCTOR (arg)
4033 && TREE_CONSTANT (arg))
4035 /* Anything not already handled and not a true memory reference
4037 else if (TREE_CODE (argtype) != FUNCTION_TYPE
4038 && TREE_CODE (argtype) != METHOD_TYPE
4039 && !lvalue_or_else (arg, "unary `&'"))
4040 return error_mark_node;
4042 if (argtype != error_mark_node)
4043 argtype = build_pointer_type (argtype);
4048 if (TREE_CODE (arg) != COMPONENT_REF
4049 /* Inside a template, we are processing a non-dependent
4050 expression so we can just form an ADDR_EXPR with the
4052 || processing_template_decl)
4053 addr = build_address (arg);
4054 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4056 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4058 /* We can only get here with a single static member
4060 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL
4061 && DECL_STATIC_FUNCTION_P (fn),
4064 addr = build_address (fn);
4065 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4066 /* Do not lose object's side effects. */
4067 addr = build (COMPOUND_EXPR, TREE_TYPE (addr),
4068 TREE_OPERAND (arg, 0), addr);
4070 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4072 error ("attempt to take address of bit-field structure member `%D'",
4073 TREE_OPERAND (arg, 1));
4074 return error_mark_node;
4078 /* Unfortunately we cannot just build an address
4079 expression here, because we would not handle
4080 address-constant-expressions or offsetof correctly. */
4081 tree field = TREE_OPERAND (arg, 1);
4082 tree rval = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
4083 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (rval)),
4084 decl_type_context (field),
4087 rval = build_base_path (PLUS_EXPR, rval, binfo, 1);
4088 rval = build_nop (argtype, rval);
4089 addr = fold (build (PLUS_EXPR, argtype, rval,
4090 cp_convert (argtype, byte_position (field))));
4093 if (TREE_CODE (argtype) == POINTER_TYPE
4094 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4096 build_ptrmemfunc_type (argtype);
4097 addr = build_ptrmemfunc (argtype, addr, 0);
4110 argtype = TREE_TYPE (arg);
4111 return fold (build1 (code, argtype, arg));
4114 error ("%s", errstring);
4115 return error_mark_node;
4118 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4119 for certain kinds of expressions which are not really lvalues
4120 but which we can accept as lvalues.
4122 If ARG is not a kind of expression we can handle, return zero. */
4125 unary_complex_lvalue (enum tree_code code, tree arg)
4127 /* Handle (a, b) used as an "lvalue". */
4128 if (TREE_CODE (arg) == COMPOUND_EXPR)
4130 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4131 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
4132 TREE_OPERAND (arg, 0), real_result);
4135 /* Handle (a ? b : c) used as an "lvalue". */
4136 if (TREE_CODE (arg) == COND_EXPR
4137 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4138 return rationalize_conditional_expr (code, arg);
4140 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4141 if (TREE_CODE (arg) == MODIFY_EXPR
4142 || TREE_CODE (arg) == PREINCREMENT_EXPR
4143 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4145 tree lvalue = TREE_OPERAND (arg, 0);
4146 if (TREE_SIDE_EFFECTS (lvalue))
4148 lvalue = stabilize_reference (lvalue);
4149 arg = build (TREE_CODE (arg), TREE_TYPE (arg),
4150 lvalue, TREE_OPERAND (arg, 1));
4152 return unary_complex_lvalue
4153 (code, build (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4156 if (code != ADDR_EXPR)
4159 /* Handle (a = b) used as an "lvalue" for `&'. */
4160 if (TREE_CODE (arg) == MODIFY_EXPR
4161 || TREE_CODE (arg) == INIT_EXPR)
4163 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4164 arg = build (COMPOUND_EXPR, TREE_TYPE (real_result), arg, real_result);
4165 TREE_NO_WARNING (arg) = 1;
4169 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4170 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4171 || TREE_CODE (arg) == OFFSET_REF)
4175 my_friendly_assert (TREE_CODE (arg) != SCOPE_REF, 313);
4177 if (TREE_CODE (arg) != OFFSET_REF)
4180 t = TREE_OPERAND (arg, 1);
4182 /* Check all this code for right semantics. */
4183 if (TREE_CODE (t) == FUNCTION_DECL)
4185 if (DECL_DESTRUCTOR_P (t))
4186 error ("taking address of destructor");
4187 return build_unary_op (ADDR_EXPR, t, 0);
4189 if (TREE_CODE (t) == VAR_DECL)
4190 return build_unary_op (ADDR_EXPR, t, 0);
4195 if (TREE_OPERAND (arg, 0)
4196 && ! is_dummy_object (TREE_OPERAND (arg, 0))
4197 && TREE_CODE (t) != FIELD_DECL)
4199 error ("taking address of bound pointer-to-member expression");
4200 return error_mark_node;
4202 if (!PTRMEM_OK_P (arg))
4203 return build_unary_op (code, arg, 0);
4205 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4207 error ("cannot create pointer to reference member `%D'", t);
4208 return error_mark_node;
4211 type = build_ptrmem_type (context_for_name_lookup (t),
4213 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4219 /* We permit compiler to make function calls returning
4220 objects of aggregate type look like lvalues. */
4224 if (TREE_CODE (targ) == SAVE_EXPR)
4225 targ = TREE_OPERAND (targ, 0);
4227 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4229 if (TREE_CODE (arg) == SAVE_EXPR)
4232 targ = build_cplus_new (TREE_TYPE (arg), arg);
4233 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4236 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4237 return build (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4238 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4241 /* Don't let anything else be handled specially. */
4245 /* Mark EXP saying that we need to be able to take the
4246 address of it; it should not be allocated in a register.
4247 Value is true if successful.
4249 C++: we do not allow `current_class_ptr' to be addressable. */
4252 cxx_mark_addressable (tree exp)
4257 switch (TREE_CODE (x))
4264 x = TREE_OPERAND (x, 0);
4268 if (x == current_class_ptr)
4270 error ("cannot take the address of `this', which is an rvalue expression");
4271 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4277 /* Caller should not be trying to mark initialized
4278 constant fields addressable. */
4279 my_friendly_assert (DECL_LANG_SPECIFIC (x) == 0
4280 || DECL_IN_AGGR_P (x) == 0
4282 || DECL_EXTERNAL (x), 314);
4287 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4288 && !DECL_ARTIFICIAL (x) && extra_warnings)
4289 warning ("address requested for `%D', which is declared `register'",
4291 TREE_ADDRESSABLE (x) = 1;
4292 put_var_into_stack (x, /*rescan=*/true);
4296 TREE_ADDRESSABLE (x) = 1;
4297 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
4301 TREE_ADDRESSABLE (x) = 1;
4305 TREE_ADDRESSABLE (x) = 1;
4306 cxx_mark_addressable (TREE_OPERAND (x, 0));
4314 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4317 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4319 tree orig_ifexp = ifexp;
4320 tree orig_op1 = op1;
4321 tree orig_op2 = op2;
4324 if (processing_template_decl)
4326 /* The standard says that the expression is type-dependent if
4327 IFEXP is type-dependent, even though the eventual type of the
4328 expression doesn't dependent on IFEXP. */
4329 if (type_dependent_expression_p (ifexp)
4330 /* As a GNU extension, the middle operand may be omitted. */
4331 || (op1 && type_dependent_expression_p (op1))
4332 || type_dependent_expression_p (op2))
4333 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4334 ifexp = build_non_dependent_expr (ifexp);
4336 op1 = build_non_dependent_expr (op1);
4337 op2 = build_non_dependent_expr (op2);
4340 expr = build_conditional_expr (ifexp, op1, op2);
4341 if (processing_template_decl && expr != error_mark_node)
4342 return build_min_non_dep (COND_EXPR, expr,
4343 orig_ifexp, orig_op1, orig_op2);
4347 /* Given a list of expressions, return a compound expression
4348 that performs them all and returns the value of the last of them. */
4350 tree build_x_compound_expr_from_list (tree list, const char *msg)
4352 tree expr = TREE_VALUE (list);
4354 if (TREE_CHAIN (list))
4357 pedwarn ("%s expression list treated as compound expression", msg);
4359 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4360 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4366 /* Handle overloading of the ',' operator when needed. */
4369 build_x_compound_expr (tree op1, tree op2)
4372 tree orig_op1 = op1;
4373 tree orig_op2 = op2;
4375 if (processing_template_decl)
4377 if (type_dependent_expression_p (op1)
4378 || type_dependent_expression_p (op2))
4379 return build_min_nt (COMPOUND_EXPR, op1, op2);
4380 op1 = build_non_dependent_expr (op1);
4381 op2 = build_non_dependent_expr (op2);
4384 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4385 /*overloaded_p=*/NULL);
4387 result = build_compound_expr (op1, op2);
4389 if (processing_template_decl && result != error_mark_node)
4390 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4395 /* Build a compound expression. */
4398 build_compound_expr (tree lhs, tree rhs)
4400 lhs = decl_constant_value (lhs);
4401 lhs = convert_to_void (lhs, "left-hand operand of comma");
4403 if (lhs == error_mark_node || rhs == error_mark_node)
4404 return error_mark_node;
4406 if (TREE_CODE (rhs) == TARGET_EXPR)
4408 /* If the rhs is a TARGET_EXPR, then build the compound
4409 expression inside the target_expr's initializer. This
4410 helps the compiler to eliminate unnecessary temporaries. */
4411 tree init = TREE_OPERAND (rhs, 1);
4413 init = build (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4414 TREE_OPERAND (rhs, 1) = init;
4419 return build (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4422 /* Issue an error message if casting from SRC_TYPE to DEST_TYPE casts
4423 away constness. DESCRIPTION explains what operation is taking
4427 check_for_casting_away_constness (tree src_type, tree dest_type,
4428 const char *description)
4430 if (casts_away_constness (src_type, dest_type))
4431 error ("%s from type `%T' to type `%T' casts away constness",
4432 description, src_type, dest_type);
4435 /* Return an expression representing static_cast<TYPE>(EXPR). */
4438 build_static_cast (tree type, tree expr)
4443 if (type == error_mark_node || expr == error_mark_node)
4444 return error_mark_node;
4446 if (processing_template_decl)
4448 expr = build_min (STATIC_CAST_EXPR, type, expr);
4449 /* We don't know if it will or will not have side effects. */
4450 TREE_SIDE_EFFECTS (expr) = 1;
4454 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4455 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4456 if (TREE_CODE (type) != REFERENCE_TYPE
4457 && TREE_CODE (expr) == NOP_EXPR
4458 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4459 expr = TREE_OPERAND (expr, 0);
4461 intype = TREE_TYPE (expr);
4463 /* [expr.static.cast]
4465 An lvalue of type "cv1 B", where B is a class type, can be cast
4466 to type "reference to cv2 D", where D is a class derived (clause
4467 _class.derived_) from B, if a valid standard conversion from
4468 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4469 same cv-qualification as, or greater cv-qualification than, cv1,
4470 and B is not a virtual base class of D. */
4471 /* We check this case before checking the validity of "TYPE t =
4472 EXPR;" below because for this case:
4475 struct D : public B { D(const B&); };
4477 void f() { static_cast<const D&>(b); }
4479 we want to avoid constructing a new D. The standard is not
4480 completely clear about this issue, but our interpretation is
4481 consistent with other compilers. */
4482 if (TREE_CODE (type) == REFERENCE_TYPE
4483 && CLASS_TYPE_P (TREE_TYPE (type))
4484 && CLASS_TYPE_P (intype)
4485 && real_lvalue_p (expr)
4486 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4487 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4488 build_pointer_type (TYPE_MAIN_VARIANT
4489 (TREE_TYPE (type))))
4490 && at_least_as_qualified_p (TREE_TYPE (type), intype))
4492 /* There is a standard conversion from "D*" to "B*" even if "B"
4493 is ambiguous or inaccessible. Therefore, we ask lookup_base
4494 to check these conditions. */
4495 tree base = lookup_base (TREE_TYPE (type), intype, ba_check, NULL);
4497 /* Convert from "B*" to "D*". This function will check that "B"
4498 is not a virtual base of "D". */
4499 expr = build_base_path (MINUS_EXPR, build_address (expr),
4500 base, /*nonnull=*/false);
4501 /* Convert the pointer to a reference -- but then remember that
4502 there are no expressions with reference type in C++. */
4503 return convert_from_reference (build_nop (type, expr));
4506 /* [expr.static.cast]
4508 An expression e can be explicitly converted to a type T using a
4509 static_cast of the form static_cast<T>(e) if the declaration T
4510 t(e);" is well-formed, for some invented temporary variable
4512 result = perform_direct_initialization_if_possible (type, expr);
4514 return convert_from_reference (result);
4516 /* [expr.static.cast]
4518 Any expression can be explicitly converted to type cv void. */
4519 if (TREE_CODE (type) == VOID_TYPE)
4520 return convert_to_void (expr, /*implicit=*/NULL);
4522 /* [expr.static.cast]
4524 The inverse of any standard conversion sequence (clause _conv_),
4525 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4526 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4527 (_conv.bool_) conversions, can be performed explicitly using
4528 static_cast subject to the restriction that the explicit
4529 conversion does not cast away constness (_expr.const.cast_), and
4530 the following additional rules for specific cases: */
4531 /* For reference, the conversions not excluded are: integral
4532 promotions, floating point promotion, integral conversions,
4533 floating point conversions, floating-integral conversions,
4534 pointer conversions, and pointer to member conversions. */
4535 if ((ARITHMETIC_TYPE_P (type) && ARITHMETIC_TYPE_P (intype))
4538 A value of integral _or enumeration_ type can be explicitly
4539 converted to an enumeration type. */
4540 || (INTEGRAL_OR_ENUMERATION_TYPE_P (type)
4541 && INTEGRAL_OR_ENUMERATION_TYPE_P (intype)))
4542 /* Really, build_c_cast should defer to this function rather
4543 than the other way around. */
4544 return build_c_cast (type, expr);
4546 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4547 && CLASS_TYPE_P (TREE_TYPE (type))
4548 && CLASS_TYPE_P (TREE_TYPE (intype))
4549 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4550 (TREE_TYPE (intype))),
4551 build_pointer_type (TYPE_MAIN_VARIANT
4552 (TREE_TYPE (type)))))
4556 check_for_casting_away_constness (intype, type, "static_cast");
4557 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype), ba_check,
4559 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4562 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4563 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4570 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4571 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4573 if (TYPE_PTRMEM_P (type))
4575 t1 = (build_ptrmem_type
4577 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4578 t2 = (build_ptrmem_type
4580 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4587 if (can_convert (t1, t2))
4589 check_for_casting_away_constness (intype, type, "static_cast");
4590 if (TYPE_PTRMEM_P (type))
4594 if (TREE_CODE (expr) == PTRMEM_CST)
4595 expr = cplus_expand_constant (expr);
4596 delta = get_delta_difference (c1, c2, /*force=*/1);
4597 if (!integer_zerop (delta))
4598 expr = cp_build_binary_op (PLUS_EXPR,
4599 build_nop (ptrdiff_type_node, expr),
4601 return build_nop (type, expr);
4604 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4609 /* [expr.static.cast]
4611 An rvalue of type "pointer to cv void" can be explicitly
4612 converted to a pointer to object type. A value of type pointer
4613 to object converted to "pointer to cv void" and back to the
4614 original pointer type will have its original value. */
4615 if (TREE_CODE (intype) == POINTER_TYPE
4616 && VOID_TYPE_P (TREE_TYPE (intype))
4617 && TYPE_PTROB_P (type))
4619 check_for_casting_away_constness (intype, type, "static_cast");
4620 return build_nop (type, expr);
4623 error ("invalid static_cast from type `%T' to type `%T'", intype, type);
4624 return error_mark_node;
4628 build_reinterpret_cast (tree type, tree expr)
4632 if (type == error_mark_node || expr == error_mark_node)
4633 return error_mark_node;
4635 if (processing_template_decl)
4637 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
4639 if (!TREE_SIDE_EFFECTS (t)
4640 && type_dependent_expression_p (expr))
4641 /* There might turn out to be side effects inside expr. */
4642 TREE_SIDE_EFFECTS (t) = 1;
4646 if (TREE_CODE (type) != REFERENCE_TYPE)
4648 expr = decay_conversion (expr);
4650 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4651 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4652 if (TREE_CODE (expr) == NOP_EXPR
4653 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4654 expr = TREE_OPERAND (expr, 0);
4657 intype = TREE_TYPE (expr);
4659 if (TREE_CODE (type) == REFERENCE_TYPE)
4661 if (! real_lvalue_p (expr))
4663 error ("invalid reinterpret_cast of an rvalue expression of type `%T' to type `%T'", intype, type);
4664 return error_mark_node;
4666 expr = build_unary_op (ADDR_EXPR, expr, 0);
4667 if (expr != error_mark_node)
4668 expr = build_reinterpret_cast
4669 (build_pointer_type (TREE_TYPE (type)), expr);
4670 if (expr != error_mark_node)
4671 expr = build_indirect_ref (expr, 0);
4674 else if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4675 return build_static_cast (type, expr);
4677 if (TYPE_PTR_P (type) && (TREE_CODE (intype) == INTEGER_TYPE
4678 || TREE_CODE (intype) == ENUMERAL_TYPE))
4680 else if (TREE_CODE (type) == INTEGER_TYPE && TYPE_PTR_P (intype))
4682 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
4683 pedwarn ("reinterpret_cast from `%T' to `%T' loses precision",
4686 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
4687 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4689 expr = decl_constant_value (expr);
4690 return fold (build1 (NOP_EXPR, type, expr));
4692 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4693 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
4695 check_for_casting_away_constness (intype, type, "reinterpret_cast");
4696 expr = decl_constant_value (expr);
4697 return fold (build1 (NOP_EXPR, type, expr));
4699 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
4700 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
4702 pedwarn ("ISO C++ forbids casting between pointer-to-function and pointer-to-object");
4703 expr = decl_constant_value (expr);
4704 return fold (build1 (NOP_EXPR, type, expr));
4708 error ("invalid reinterpret_cast from type `%T' to type `%T'",
4710 return error_mark_node;
4713 return cp_convert (type, expr);
4717 build_const_cast (tree type, tree expr)
4721 if (type == error_mark_node || expr == error_mark_node)
4722 return error_mark_node;
4724 if (processing_template_decl)
4726 tree t = build_min (CONST_CAST_EXPR, type, expr);
4728 if (!TREE_SIDE_EFFECTS (t)
4729 && type_dependent_expression_p (expr))
4730 /* There might turn out to be side effects inside expr. */
4731 TREE_SIDE_EFFECTS (t) = 1;
4735 if (!POINTER_TYPE_P (type) && !TYPE_PTRMEM_P (type))
4736 error ("invalid use of const_cast with type `%T', which is not a pointer, reference, nor a pointer-to-data-member type", type);
4737 else if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4739 error ("invalid use of const_cast with type `%T', which is a pointer or reference to a function type", type);
4740 return error_mark_node;
4743 if (TREE_CODE (type) != REFERENCE_TYPE)
4745 expr = decay_conversion (expr);
4747 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4748 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4749 if (TREE_CODE (expr) == NOP_EXPR
4750 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4751 expr = TREE_OPERAND (expr, 0);
4754 intype = TREE_TYPE (expr);
4756 if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4757 return build_static_cast (type, expr);
4758 else if (TREE_CODE (type) == REFERENCE_TYPE)
4760 if (! real_lvalue_p (expr))
4762 error ("invalid const_cast of an rvalue of type `%T' to type `%T'", intype, type);
4763 return error_mark_node;
4766 if (comp_ptr_ttypes_const (TREE_TYPE (type), intype))
4768 expr = build_unary_op (ADDR_EXPR, expr, 0);
4769 expr = build1 (NOP_EXPR, type, expr);
4770 return convert_from_reference (expr);
4773 else if (((TREE_CODE (type) == POINTER_TYPE
4774 && TREE_CODE (intype) == POINTER_TYPE)
4775 || (TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype)))
4776 && comp_ptr_ttypes_const (TREE_TYPE (type), TREE_TYPE (intype)))
4777 return cp_convert (type, expr);
4779 error ("invalid const_cast from type `%T' to type `%T'", intype, type);
4780 return error_mark_node;
4783 /* Build an expression representing a cast to type TYPE of expression EXPR.
4785 ALLOW_NONCONVERTING is true if we should allow non-converting constructors
4786 when doing the cast. */
4789 build_c_cast (tree type, tree expr)
4794 if (type == error_mark_node || expr == error_mark_node)
4795 return error_mark_node;
4797 if (processing_template_decl)
4799 tree t = build_min (CAST_EXPR, type,
4800 tree_cons (NULL_TREE, value, NULL_TREE));
4801 /* We don't know if it will or will not have side effects. */
4802 TREE_SIDE_EFFECTS (t) = 1;
4806 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4807 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4808 if (TREE_CODE (type) != REFERENCE_TYPE
4809 && TREE_CODE (value) == NOP_EXPR
4810 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
4811 value = TREE_OPERAND (value, 0);
4813 if (TREE_CODE (type) == ARRAY_TYPE)
4815 /* Allow casting from T1* to T2[] because Cfront allows it.
4816 NIHCL uses it. It is not valid ISO C++ however. */
4817 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
4819 pedwarn ("ISO C++ forbids casting to an array type `%T'", type);
4820 type = build_pointer_type (TREE_TYPE (type));
4824 error ("ISO C++ forbids casting to an array type `%T'", type);
4825 return error_mark_node;
4829 if (TREE_CODE (type) == FUNCTION_TYPE
4830 || TREE_CODE (type) == METHOD_TYPE)
4832 error ("invalid cast to function type `%T'", type);
4833 return error_mark_node;
4836 if (TREE_CODE (type) == VOID_TYPE)
4838 /* Conversion to void does not cause any of the normal function to
4839 * pointer, array to pointer and lvalue to rvalue decays. */
4841 value = convert_to_void (value, /*implicit=*/NULL);
4845 if (!complete_type_or_else (type, NULL_TREE))
4846 return error_mark_node;
4848 /* Convert functions and arrays to pointers and
4849 convert references to their expanded types,
4850 but don't convert any other types. If, however, we are
4851 casting to a class type, there's no reason to do this: the
4852 cast will only succeed if there is a converting constructor,
4853 and the default conversions will be done at that point. In
4854 fact, doing the default conversion here is actually harmful
4858 struct S { S(const A&); };
4860 since we don't want the array-to-pointer conversion done. */
4861 if (!IS_AGGR_TYPE (type))
4863 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
4864 || (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE
4865 /* Don't do the default conversion on a ->* expression. */
4866 && ! (TREE_CODE (type) == POINTER_TYPE
4867 && bound_pmf_p (value)))
4868 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
4869 || TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4870 value = decay_conversion (value);
4872 else if (TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4873 /* However, even for class types, we still need to strip away
4874 the reference type, since the call to convert_force below
4875 does not expect the input expression to be of reference
4877 value = convert_from_reference (value);
4879 otype = TREE_TYPE (value);
4881 /* Optionally warn about potentially worrisome casts. */
4884 && TREE_CODE (type) == POINTER_TYPE
4885 && TREE_CODE (otype) == POINTER_TYPE
4886 && !at_least_as_qualified_p (TREE_TYPE (type),
4888 warning ("cast from `%T' to `%T' discards qualifiers from pointer target type",
4891 if (TREE_CODE (type) == INTEGER_TYPE
4892 && TYPE_PTR_P (otype)
4893 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
4894 warning ("cast from pointer to integer of different size");
4896 if (TYPE_PTR_P (type)
4897 && TREE_CODE (otype) == INTEGER_TYPE
4898 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
4899 /* Don't warn about converting any constant. */
4900 && !TREE_CONSTANT (value))
4901 warning ("cast to pointer from integer of different size");
4903 if (TREE_CODE (type) == REFERENCE_TYPE)
4904 value = (convert_from_reference
4905 (convert_to_reference (type, value, CONV_C_CAST,
4906 LOOKUP_COMPLAIN, NULL_TREE)));
4911 value = decl_constant_value (value);
4914 value = convert_force (type, value, CONV_C_CAST);
4916 /* Ignore any integer overflow caused by the cast. */
4917 if (TREE_CODE (value) == INTEGER_CST)
4919 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
4921 if (TREE_CODE_CLASS (TREE_CODE (ovalue)) == 'c')
4922 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
4926 /* Warn about possible alignment problems. Do this here when we will have
4927 instantiated any necessary template types. */
4928 if (STRICT_ALIGNMENT && warn_cast_align
4929 && TREE_CODE (type) == POINTER_TYPE
4930 && TREE_CODE (otype) == POINTER_TYPE
4931 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
4932 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
4933 && COMPLETE_TYPE_P (TREE_TYPE (otype))
4934 && COMPLETE_TYPE_P (TREE_TYPE (type))
4935 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
4936 warning ("cast from `%T' to `%T' increases required alignment of target type",
4939 /* Always produce some operator for an explicit cast,
4940 so we can tell (for -pedantic) that the cast is no lvalue. */
4941 if (TREE_CODE (type) != REFERENCE_TYPE && value == expr
4942 && real_lvalue_p (value))
4943 value = non_lvalue (value);
4948 /* Build an assignment expression of lvalue LHS from value RHS.
4949 MODIFYCODE is the code for a binary operator that we use
4950 to combine the old value of LHS with RHS to get the new value.
4951 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
4953 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
4956 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
4960 tree lhstype = TREE_TYPE (lhs);
4961 tree olhstype = lhstype;
4962 tree olhs = NULL_TREE;
4964 /* Avoid duplicate error messages from operands that had errors. */
4965 if (lhs == error_mark_node || rhs == error_mark_node)
4966 return error_mark_node;
4968 /* Handle control structure constructs used as "lvalues". */
4969 switch (TREE_CODE (lhs))
4971 /* Handle --foo = 5; as these are valid constructs in C++. */
4972 case PREDECREMENT_EXPR:
4973 case PREINCREMENT_EXPR:
4974 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4975 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4976 stabilize_reference (TREE_OPERAND (lhs, 0)),
4977 TREE_OPERAND (lhs, 1));
4978 return build (COMPOUND_EXPR, lhstype,
4980 build_modify_expr (TREE_OPERAND (lhs, 0),
4983 /* Handle (a, b) used as an "lvalue". */
4985 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
4987 if (newrhs == error_mark_node)
4988 return error_mark_node;
4989 return build (COMPOUND_EXPR, lhstype,
4990 TREE_OPERAND (lhs, 0), newrhs);
4993 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4994 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4995 stabilize_reference (TREE_OPERAND (lhs, 0)),
4996 TREE_OPERAND (lhs, 1));
4997 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
4998 if (newrhs == error_mark_node)
4999 return error_mark_node;
5000 return build (COMPOUND_EXPR, lhstype, lhs, newrhs);
5002 /* Handle (a ? b : c) used as an "lvalue". */
5005 /* Produce (a ? (b = rhs) : (c = rhs))
5006 except that the RHS goes through a save-expr
5007 so the code to compute it is only emitted once. */
5009 tree preeval = NULL_TREE;
5011 rhs = stabilize_expr (rhs, &preeval);
5013 /* Check this here to avoid odd errors when trying to convert
5014 a throw to the type of the COND_EXPR. */
5015 if (!lvalue_or_else (lhs, "assignment"))
5016 return error_mark_node;
5018 cond = build_conditional_expr
5019 (TREE_OPERAND (lhs, 0),
5020 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5021 TREE_OPERAND (lhs, 1)),
5023 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5024 TREE_OPERAND (lhs, 2)),
5027 if (cond == error_mark_node)
5029 /* Make sure the code to compute the rhs comes out
5030 before the split. */
5032 cond = build (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5040 if (modifycode == INIT_EXPR)
5042 if (TREE_CODE (rhs) == CONSTRUCTOR)
5044 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5045 /* Call convert to generate an error; see PR 11063. */
5046 rhs = convert (lhstype, rhs);
5047 result = build (INIT_EXPR, lhstype, lhs, rhs);
5048 TREE_SIDE_EFFECTS (result) = 1;
5051 else if (! IS_AGGR_TYPE (lhstype))
5052 /* Do the default thing. */;
5055 result = build_special_member_call (lhs, complete_ctor_identifier,
5056 build_tree_list (NULL_TREE, rhs),
5057 TYPE_BINFO (lhstype),
5059 if (result == NULL_TREE)
5060 return error_mark_node;
5066 if (TREE_CODE (lhstype) == REFERENCE_TYPE)
5068 lhs = convert_from_reference (lhs);
5069 olhstype = lhstype = TREE_TYPE (lhs);
5071 lhs = require_complete_type (lhs);
5072 if (lhs == error_mark_node)
5073 return error_mark_node;
5075 if (modifycode == NOP_EXPR)
5077 /* `operator=' is not an inheritable operator. */
5078 if (! IS_AGGR_TYPE (lhstype))
5079 /* Do the default thing. */;
5082 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5083 lhs, rhs, make_node (NOP_EXPR),
5084 /*overloaded_p=*/NULL);
5085 if (result == NULL_TREE)
5086 return error_mark_node;
5093 /* A binary op has been requested. Combine the old LHS
5094 value with the RHS producing the value we should actually
5095 store into the LHS. */
5097 my_friendly_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE),
5099 lhs = stabilize_reference (lhs);
5100 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5101 if (newrhs == error_mark_node)
5103 error (" in evaluation of `%Q(%#T, %#T)'", modifycode,
5104 TREE_TYPE (lhs), TREE_TYPE (rhs));
5105 return error_mark_node;
5108 /* Now it looks like a plain assignment. */
5109 modifycode = NOP_EXPR;
5111 my_friendly_assert (TREE_CODE (lhstype) != REFERENCE_TYPE, 20011220);
5112 my_friendly_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE,
5116 /* The left-hand side must be an lvalue. */
5117 if (!lvalue_or_else (lhs, "assignment"))
5118 return error_mark_node;
5120 /* Warn about modifying something that is `const'. Don't warn if
5121 this is initialization. */
5122 if (modifycode != INIT_EXPR
5123 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5124 /* Functions are not modifiable, even though they are
5126 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5127 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5128 /* If it's an aggregate and any field is const, then it is
5129 effectively const. */
5130 || (CLASS_TYPE_P (lhstype)
5131 && C_TYPE_FIELDS_READONLY (lhstype))))
5132 readonly_error (lhs, "assignment", 0);
5134 /* If storing into a structure or union member, it has probably been
5135 given type `int'. Compute the type that would go with the actual
5136 amount of storage the member occupies. */
5138 if (TREE_CODE (lhs) == COMPONENT_REF
5139 && (TREE_CODE (lhstype) == INTEGER_TYPE
5140 || TREE_CODE (lhstype) == REAL_TYPE
5141 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5143 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5145 /* If storing in a field that is in actuality a short or narrower
5146 than one, we must store in the field in its actual type. */
5148 if (lhstype != TREE_TYPE (lhs))
5150 /* Avoid warnings converting integral types back into enums for
5152 if (TREE_CODE (lhstype) == INTEGER_TYPE
5153 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5155 if (TREE_SIDE_EFFECTS (lhs))
5156 lhs = stabilize_reference (lhs);
5159 lhs = copy_node (lhs);
5160 TREE_TYPE (lhs) = lhstype;
5164 /* Convert new value to destination type. */
5166 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5170 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5171 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5173 error ("incompatible types in assignment of `%T' to `%T'",
5174 TREE_TYPE (rhs), lhstype);
5175 return error_mark_node;
5178 /* Allow array assignment in compiler-generated code. */
5179 if (! DECL_ARTIFICIAL (current_function_decl))
5180 pedwarn ("ISO C++ forbids assignment of arrays");
5182 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5183 ? 1 + (modifycode != INIT_EXPR): 0;
5184 return build_vec_init (lhs, NULL_TREE, newrhs, from_array);
5187 if (modifycode == INIT_EXPR)
5188 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5189 "initialization", NULL_TREE, 0);
5192 /* Avoid warnings on enum bit fields. */
5193 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5194 && TREE_CODE (lhstype) == INTEGER_TYPE)
5196 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5198 newrhs = convert_force (lhstype, newrhs, 0);
5201 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5203 if (TREE_CODE (newrhs) == CALL_EXPR
5204 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5205 newrhs = build_cplus_new (lhstype, newrhs);
5207 /* Can't initialize directly from a TARGET_EXPR, since that would
5208 cause the lhs to be constructed twice, and possibly result in
5209 accidental self-initialization. So we force the TARGET_EXPR to be
5210 expanded without a target. */
5211 if (TREE_CODE (newrhs) == TARGET_EXPR)
5212 newrhs = build (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5213 TREE_OPERAND (newrhs, 0));
5216 if (newrhs == error_mark_node)
5217 return error_mark_node;
5219 result = build (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5220 lhstype, lhs, newrhs);
5222 TREE_SIDE_EFFECTS (result) = 1;
5224 /* If we got the LHS in a different type for storing in,
5225 convert the result back to the nominal type of LHS
5226 so that the value we return always has the same type
5227 as the LHS argument. */
5229 if (olhstype == TREE_TYPE (result))
5233 result = build (COMPOUND_EXPR, olhstype, result, olhs);
5234 TREE_NO_WARNING (result) = 1;
5237 return convert_for_assignment (olhstype, result, "assignment",
5242 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5244 if (processing_template_decl)
5245 return build_min_nt (MODOP_EXPR, lhs,
5246 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5248 if (modifycode != NOP_EXPR)
5250 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5251 make_node (modifycode),
5252 /*overloaded_p=*/NULL);
5256 return build_modify_expr (lhs, modifycode, rhs);
5260 /* Get difference in deltas for different pointer to member function
5261 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5262 the conversion is invalid, the constant is zero. If FORCE is true,
5263 then allow reverse conversions as well.
5265 Note that the naming of FROM and TO is kind of backwards; the return
5266 value is what we add to a TO in order to get a FROM. They are named
5267 this way because we call this function to find out how to convert from
5268 a pointer to member of FROM to a pointer to member of TO. */
5271 get_delta_difference (tree from, tree to, int force)
5278 /* Assume no conversion is required. */
5279 result = integer_zero_node;
5280 binfo = lookup_base (to, from, ba_check, &kind);
5281 if (kind == bk_inaccessible || kind == bk_ambig)
5282 error (" in pointer to member function conversion");
5287 error_not_base_type (from, to);
5288 error (" in pointer to member conversion");
5292 binfo = lookup_base (from, to, ba_check, &kind);
5295 virt_binfo = binfo_from_vbase (binfo);
5297 /* This is a reinterpret cast, we choose to do nothing. */
5298 warning ("pointer to member cast via virtual base `%T'",
5299 BINFO_TYPE (virt_binfo));
5301 result = size_diffop (size_zero_node, BINFO_OFFSET (binfo));
5307 virt_binfo = binfo_from_vbase (binfo);
5309 result = BINFO_OFFSET (binfo);
5312 /* This is a reinterpret cast, we choose to do nothing. */
5314 warning ("pointer to member cast via virtual base `%T'",
5315 BINFO_TYPE (virt_binfo));
5317 error ("pointer to member conversion via virtual base `%T'",
5318 BINFO_TYPE (virt_binfo));
5322 return fold (convert_to_integer (ptrdiff_type_node, result));
5325 /* Return a constructor for the pointer-to-member-function TYPE using
5326 the other components as specified. */
5329 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5335 /* Pull the FIELD_DECLs out of the type. */
5336 pfn_field = TYPE_FIELDS (type);
5337 delta_field = TREE_CHAIN (pfn_field);
5339 /* Make sure DELTA has the type we want. */
5340 delta = convert_and_check (delta_type_node, delta);
5342 /* Finish creating the initializer. */
5343 u = tree_cons (pfn_field, pfn,
5344 build_tree_list (delta_field, delta));
5345 u = build_constructor (type, u);
5346 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
5347 TREE_INVARIANT (u) = TREE_INVARIANT (pfn) & TREE_INVARIANT (delta);
5348 TREE_STATIC (u) = (TREE_CONSTANT (u)
5349 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5351 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5356 /* Build a constructor for a pointer to member function. It can be
5357 used to initialize global variables, local variable, or used
5358 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5361 If FORCE is nonzero, then force this conversion, even if
5362 we would rather not do it. Usually set when using an explicit
5365 Return error_mark_node, if something goes wrong. */
5368 build_ptrmemfunc (tree type, tree pfn, int force)
5374 if (error_operand_p (pfn))
5375 return error_mark_node;
5377 pfn_type = TREE_TYPE (pfn);
5378 to_type = build_ptrmemfunc_type (type);
5380 /* Handle multiple conversions of pointer to member functions. */
5381 if (TYPE_PTRMEMFUNC_P (pfn_type))
5383 tree delta = NULL_TREE;
5384 tree npfn = NULL_TREE;
5388 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn))
5389 error ("invalid conversion to type `%T' from type `%T'",
5392 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5393 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5396 /* We don't have to do any conversion to convert a
5397 pointer-to-member to its own type. But, we don't want to
5398 just return a PTRMEM_CST if there's an explicit cast; that
5399 cast should make the expression an invalid template argument. */
5400 if (TREE_CODE (pfn) != PTRMEM_CST)
5402 if (same_type_p (to_type, pfn_type))
5404 else if (integer_zerop (n))
5405 return build_reinterpret_cast (to_type, pfn);
5408 if (TREE_SIDE_EFFECTS (pfn))
5409 pfn = save_expr (pfn);
5411 /* Obtain the function pointer and the current DELTA. */
5412 if (TREE_CODE (pfn) == PTRMEM_CST)
5413 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
5416 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
5417 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
5420 /* Just adjust the DELTA field. */
5421 my_friendly_assert (TREE_TYPE (delta) == ptrdiff_type_node, 20030727);
5422 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
5423 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
5424 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
5425 return build_ptrmemfunc1 (to_type, delta, npfn);
5428 /* Handle null pointer to member function conversions. */
5429 if (integer_zerop (pfn))
5431 pfn = build_c_cast (type, integer_zero_node);
5432 return build_ptrmemfunc1 (to_type,
5437 if (type_unknown_p (pfn))
5438 return instantiate_type (type, pfn, tf_error | tf_warning);
5440 fn = TREE_OPERAND (pfn, 0);
5441 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5442 return make_ptrmem_cst (to_type, fn);
5445 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
5448 ??? There is no consistency as to the types returned for the above
5449 values. Some code acts as if it were a sizetype and some as if it were
5450 integer_type_node. */
5453 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
5455 tree type = TREE_TYPE (cst);
5456 tree fn = PTRMEM_CST_MEMBER (cst);
5457 tree ptr_class, fn_class;
5459 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5461 /* The class that the function belongs to. */
5462 fn_class = DECL_CONTEXT (fn);
5464 /* The class that we're creating a pointer to member of. */
5465 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
5467 /* First, calculate the adjustment to the function's class. */
5468 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0);
5470 if (!DECL_VIRTUAL_P (fn))
5471 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
5474 /* If we're dealing with a virtual function, we have to adjust 'this'
5475 again, to point to the base which provides the vtable entry for
5476 fn; the call will do the opposite adjustment. */
5477 tree orig_class = DECL_CONTEXT (fn);
5478 tree binfo = binfo_or_else (orig_class, fn_class);
5479 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5480 *delta, BINFO_OFFSET (binfo)));
5482 /* We set PFN to the vtable offset at which the function can be
5483 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
5484 case delta is shifted left, and then incremented). */
5485 *pfn = DECL_VINDEX (fn);
5486 *pfn = fold (build (MULT_EXPR, integer_type_node, *pfn,
5487 TYPE_SIZE_UNIT (vtable_entry_type)));
5489 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
5491 case ptrmemfunc_vbit_in_pfn:
5492 *pfn = fold (build (PLUS_EXPR, integer_type_node, *pfn,
5496 case ptrmemfunc_vbit_in_delta:
5497 *delta = fold (build (LSHIFT_EXPR, TREE_TYPE (*delta),
5498 *delta, integer_one_node));
5499 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5500 *delta, integer_one_node));
5507 *pfn = fold (build1 (NOP_EXPR, TYPE_PTRMEMFUNC_FN_TYPE (type),
5512 /* Return an expression for PFN from the pointer-to-member function
5516 pfn_from_ptrmemfunc (tree t)
5518 if (TREE_CODE (t) == PTRMEM_CST)
5523 expand_ptrmemfunc_cst (t, &delta, &pfn);
5528 return build_ptrmemfunc_access_expr (t, pfn_identifier);
5531 /* Expression EXPR is about to be implicitly converted to TYPE. Warn
5532 if this is a potentially dangerous thing to do. Returns a possibly
5536 dubious_conversion_warnings (tree type, tree expr,
5537 const char *errtype, tree fndecl, int parmnum)
5539 type = non_reference (type);
5541 /* Issue warnings about peculiar, but valid, uses of NULL. */
5542 if (ARITHMETIC_TYPE_P (type) && expr == null_node)
5545 warning ("passing NULL used for non-pointer %s %P of `%D'",
5546 errtype, parmnum, fndecl);
5548 warning ("%s to non-pointer type `%T' from NULL", errtype, type);
5551 /* Warn about assigning a floating-point type to an integer type. */
5552 if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE
5553 && TREE_CODE (type) == INTEGER_TYPE)
5556 warning ("passing `%T' for %s %P of `%D'",
5557 TREE_TYPE (expr), errtype, parmnum, fndecl);
5559 warning ("%s to `%T' from `%T'", errtype, type, TREE_TYPE (expr));
5561 /* And warn about assigning a negative value to an unsigned
5563 else if (TYPE_UNSIGNED (type) && TREE_CODE (type) != BOOLEAN_TYPE)
5565 if (TREE_CODE (expr) == INTEGER_CST && TREE_NEGATED_INT (expr))
5568 warning ("passing negative value `%E' for %s %P of `%D'",
5569 expr, errtype, parmnum, fndecl);
5571 warning ("%s of negative value `%E' to `%T'",
5572 errtype, expr, type);
5575 overflow_warning (expr);
5577 if (TREE_CONSTANT (expr))
5583 /* Convert value RHS to type TYPE as preparation for an assignment to
5584 an lvalue of type TYPE. ERRTYPE is a string to use in error
5585 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
5586 are doing the conversion in order to pass the PARMNUMth argument of
5590 convert_for_assignment (tree type, tree rhs,
5591 const char *errtype, tree fndecl, int parmnum)
5594 enum tree_code coder;
5596 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
5597 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
5598 rhs = TREE_OPERAND (rhs, 0);
5600 rhstype = TREE_TYPE (rhs);
5601 coder = TREE_CODE (rhstype);
5603 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
5604 && vector_types_convertible_p (type, rhstype))
5605 return convert (type, rhs);
5607 if (rhs == error_mark_node || rhstype == error_mark_node)
5608 return error_mark_node;
5609 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
5610 return error_mark_node;
5612 /* The RHS of an assignment cannot have void type. */
5613 if (coder == VOID_TYPE)
5615 error ("void value not ignored as it ought to be");
5616 return error_mark_node;
5619 /* Simplify the RHS if possible. */
5620 if (TREE_CODE (rhs) == CONST_DECL)
5621 rhs = DECL_INITIAL (rhs);
5623 /* We do not use decl_constant_value here because of this case:
5625 const char* const s = "s";
5627 The conversion rules for a string literal are more lax than for a
5628 variable; in particular, a string literal can be converted to a
5629 "char *" but the variable "s" cannot be converted in the same
5630 way. If the conversion is allowed, the optimization should be
5631 performed while creating the converted expression. */
5635 The expression is implicitly converted (clause _conv_) to the
5636 cv-unqualified type of the left operand.
5638 We allow bad conversions here because by the time we get to this point
5639 we are committed to doing the conversion. If we end up doing a bad
5640 conversion, convert_like will complain. */
5641 if (!can_convert_arg_bad (type, rhstype, rhs))
5643 /* When -Wno-pmf-conversions is use, we just silently allow
5644 conversions from pointers-to-members to plain pointers. If
5645 the conversion doesn't work, cp_convert will complain. */
5647 && TYPE_PTR_P (type)
5648 && TYPE_PTRMEMFUNC_P (rhstype))
5649 rhs = cp_convert (strip_top_quals (type), rhs);
5652 /* If the right-hand side has unknown type, then it is an
5653 overloaded function. Call instantiate_type to get error
5655 if (rhstype == unknown_type_node)
5656 instantiate_type (type, rhs, tf_error | tf_warning);
5658 error ("cannot convert `%T' to `%T' for argument `%P' to `%D'",
5659 rhstype, type, parmnum, fndecl);
5661 error ("cannot convert `%T' to `%T' in %s", rhstype, type,
5663 return error_mark_node;
5666 return perform_implicit_conversion (strip_top_quals (type), rhs);
5669 /* Convert RHS to be of type TYPE.
5670 If EXP is nonzero, it is the target of the initialization.
5671 ERRTYPE is a string to use in error messages.
5673 Two major differences between the behavior of
5674 `convert_for_assignment' and `convert_for_initialization'
5675 are that references are bashed in the former, while
5676 copied in the latter, and aggregates are assigned in
5677 the former (operator=) while initialized in the
5680 If using constructor make sure no conversion operator exists, if one does
5681 exist, an ambiguity exists.
5683 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
5686 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
5687 const char *errtype, tree fndecl, int parmnum)
5689 enum tree_code codel = TREE_CODE (type);
5691 enum tree_code coder;
5693 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5694 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
5695 if (TREE_CODE (rhs) == NOP_EXPR
5696 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
5697 && codel != REFERENCE_TYPE)
5698 rhs = TREE_OPERAND (rhs, 0);
5700 if (rhs == error_mark_node
5701 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
5702 return error_mark_node;
5704 if (TREE_CODE (TREE_TYPE (rhs)) == REFERENCE_TYPE)
5705 rhs = convert_from_reference (rhs);
5707 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
5708 && TREE_CODE (type) != ARRAY_TYPE
5709 && (TREE_CODE (type) != REFERENCE_TYPE
5710 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
5711 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
5712 && (TREE_CODE (type) != REFERENCE_TYPE
5713 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
5714 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
5715 rhs = decay_conversion (rhs);
5717 rhstype = TREE_TYPE (rhs);
5718 coder = TREE_CODE (rhstype);
5720 if (coder == ERROR_MARK)
5721 return error_mark_node;
5723 /* We accept references to incomplete types, so we can
5724 return here before checking if RHS is of complete type. */
5726 if (codel == REFERENCE_TYPE)
5728 /* This should eventually happen in convert_arguments. */
5729 int savew = 0, savee = 0;
5732 savew = warningcount, savee = errorcount;
5733 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
5737 if (warningcount > savew)
5738 cp_warning_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5739 else if (errorcount > savee)
5740 cp_error_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5746 exp = require_complete_type (exp);
5747 if (exp == error_mark_node)
5748 return error_mark_node;
5750 rhstype = non_reference (rhstype);
5752 type = complete_type (type);
5754 if (IS_AGGR_TYPE (type))
5755 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
5757 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
5760 /* Expand an ASM statement with operands, handling output operands
5761 that are not variables or INDIRECT_REFS by transforming such
5762 cases into cases that expand_asm_operands can handle.
5764 Arguments are same as for expand_asm_operands.
5766 We don't do default conversions on all inputs, because it can screw
5767 up operands that are expected to be in memory. */
5770 c_expand_asm_operands (tree string, tree outputs, tree inputs, tree clobbers,
5771 int vol, location_t locus)
5773 int noutputs = list_length (outputs);
5775 /* o[I] is the place that output number I should be written. */
5776 tree *o = alloca (noutputs * sizeof (tree));
5779 /* Record the contents of OUTPUTS before it is modified. */
5780 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5781 o[i] = TREE_VALUE (tail);
5783 /* Generate the ASM_OPERANDS insn;
5784 store into the TREE_VALUEs of OUTPUTS some trees for
5785 where the values were actually stored. */
5786 expand_asm_operands (string, outputs, inputs, clobbers, vol, locus);
5788 /* Copy all the intermediate outputs into the specified outputs. */
5789 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5791 if (o[i] != TREE_VALUE (tail))
5793 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
5794 const0_rtx, VOIDmode, EXPAND_NORMAL);
5797 /* Restore the original value so that it's correct the next
5798 time we expand this function. */
5799 TREE_VALUE (tail) = o[i];
5801 /* Detect modification of read-only values.
5802 (Otherwise done by build_modify_expr.) */
5805 tree type = TREE_TYPE (o[i]);
5806 if (type != error_mark_node
5807 && (CP_TYPE_CONST_P (type)
5808 || (CLASS_TYPE_P (type) && C_TYPE_FIELDS_READONLY (type))))
5809 readonly_error (o[i], "modification by `asm'", 1);
5813 /* Those MODIFY_EXPRs could do autoincrements. */
5817 /* If RETVAL is the address of, or a reference to, a local variable or
5818 temporary give an appropriate warning. */
5821 maybe_warn_about_returning_address_of_local (tree retval)
5823 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
5824 tree whats_returned = retval;
5828 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
5829 whats_returned = TREE_OPERAND (whats_returned, 1);
5830 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
5831 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
5832 || TREE_CODE (whats_returned) == NOP_EXPR)
5833 whats_returned = TREE_OPERAND (whats_returned, 0);
5838 if (TREE_CODE (whats_returned) != ADDR_EXPR)
5840 whats_returned = TREE_OPERAND (whats_returned, 0);
5842 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5844 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
5845 || TREE_CODE (whats_returned) == TARGET_EXPR)
5847 warning ("returning reference to temporary");
5850 if (TREE_CODE (whats_returned) == VAR_DECL
5851 && DECL_NAME (whats_returned)
5852 && TEMP_NAME_P (DECL_NAME (whats_returned)))
5854 warning ("reference to non-lvalue returned");
5859 if (DECL_P (whats_returned)
5860 && DECL_NAME (whats_returned)
5861 && DECL_FUNCTION_SCOPE_P (whats_returned)
5862 && !(TREE_STATIC (whats_returned)
5863 || TREE_PUBLIC (whats_returned)))
5865 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5866 cp_warning_at ("reference to local variable `%D' returned",
5869 cp_warning_at ("address of local variable `%D' returned",
5875 /* Check that returning RETVAL from the current function is valid.
5876 Return an expression explicitly showing all conversions required to
5877 change RETVAL into the function return type, and to assign it to
5878 the DECL_RESULT for the function. */
5881 check_return_expr (tree retval)
5884 /* The type actually returned by the function, after any
5887 int fn_returns_value_p;
5889 /* A `volatile' function is one that isn't supposed to return, ever.
5890 (This is a G++ extension, used to get better code for functions
5891 that call the `volatile' function.) */
5892 if (TREE_THIS_VOLATILE (current_function_decl))
5893 warning ("function declared `noreturn' has a `return' statement");
5895 /* Check for various simple errors. */
5896 if (DECL_DESTRUCTOR_P (current_function_decl))
5899 error ("returning a value from a destructor");
5902 else if (DECL_CONSTRUCTOR_P (current_function_decl))
5904 if (in_function_try_handler)
5905 /* If a return statement appears in a handler of the
5906 function-try-block of a constructor, the program is ill-formed. */
5907 error ("cannot return from a handler of a function-try-block of a constructor");
5909 /* You can't return a value from a constructor. */
5910 error ("returning a value from a constructor");
5914 if (processing_template_decl)
5916 current_function_returns_value = 1;
5920 /* When no explicit return-value is given in a function with a named
5921 return value, the named return value is used. */
5922 result = DECL_RESULT (current_function_decl);
5923 valtype = TREE_TYPE (result);
5924 my_friendly_assert (valtype != NULL_TREE, 19990924);
5925 fn_returns_value_p = !VOID_TYPE_P (valtype);
5926 if (!retval && DECL_NAME (result) && fn_returns_value_p)
5929 /* Check for a return statement with no return value in a function
5930 that's supposed to return a value. */
5931 if (!retval && fn_returns_value_p)
5933 pedwarn ("return-statement with no value, in function returning '%T'",
5935 /* Clear this, so finish_function won't say that we reach the
5936 end of a non-void function (which we don't, we gave a
5938 current_function_returns_null = 0;
5940 /* Check for a return statement with a value in a function that
5941 isn't supposed to return a value. */
5942 else if (retval && !fn_returns_value_p)
5944 if (VOID_TYPE_P (TREE_TYPE (retval)))
5945 /* You can return a `void' value from a function of `void'
5946 type. In that case, we have to evaluate the expression for
5947 its side-effects. */
5948 finish_expr_stmt (retval);
5950 pedwarn ("return-statement with a value, in function "
5951 "returning 'void'");
5953 current_function_returns_null = 1;
5955 /* There's really no value to return, after all. */
5959 /* Remember that this function can sometimes return without a
5961 current_function_returns_null = 1;
5963 /* Remember that this function did return a value. */
5964 current_function_returns_value = 1;
5966 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
5967 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
5968 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
5969 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
5971 && null_ptr_cst_p (retval))
5972 warning ("`operator new' must not return NULL unless it is declared `throw()' (or -fcheck-new is in effect)");
5974 /* Effective C++ rule 15. See also start_function. */
5976 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR)
5977 && retval != current_class_ref)
5978 warning ("`operator=' should return a reference to `*this'");
5980 /* The fabled Named Return Value optimization, as per [class.copy]/15:
5982 [...] For a function with a class return type, if the expression
5983 in the return statement is the name of a local object, and the cv-
5984 unqualified type of the local object is the same as the function
5985 return type, an implementation is permitted to omit creating the tem-
5986 porary object to hold the function return value [...]
5988 So, if this is a value-returning function that always returns the same
5989 local variable, remember it.
5991 It might be nice to be more flexible, and choose the first suitable
5992 variable even if the function sometimes returns something else, but
5993 then we run the risk of clobbering the variable we chose if the other
5994 returned expression uses the chosen variable somehow. And people expect
5995 this restriction, anyway. (jason 2000-11-19)
5997 See finish_function and finalize_nrv for the rest of this optimization. */
5999 if (fn_returns_value_p && flag_elide_constructors)
6001 if (retval != NULL_TREE
6002 && (current_function_return_value == NULL_TREE
6003 || current_function_return_value == retval)
6004 && TREE_CODE (retval) == VAR_DECL
6005 && DECL_CONTEXT (retval) == current_function_decl
6006 && ! TREE_STATIC (retval)
6007 && (DECL_ALIGN (retval)
6008 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6009 && same_type_p ((TYPE_MAIN_VARIANT
6010 (TREE_TYPE (retval))),
6012 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
6013 current_function_return_value = retval;
6015 current_function_return_value = error_mark_node;
6018 /* We don't need to do any conversions when there's nothing being
6020 if (!retval || retval == error_mark_node)
6023 /* Do any required conversions. */
6024 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6025 /* No conversions are required. */
6029 /* The type the function is declared to return. */
6030 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6032 /* First convert the value to the function's return type, then
6033 to the type of return value's location to handle the
6034 case that functype is smaller than the valtype. */
6035 retval = convert_for_initialization
6036 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6037 "return", NULL_TREE, 0);
6038 retval = convert (valtype, retval);
6040 /* If the conversion failed, treat this just like `return;'. */
6041 if (retval == error_mark_node)
6043 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6044 else if (! current_function_returns_struct
6045 && TREE_CODE (retval) == TARGET_EXPR
6046 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6047 retval = build (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6048 TREE_OPERAND (retval, 0));
6050 maybe_warn_about_returning_address_of_local (retval);
6053 /* Actually copy the value returned into the appropriate location. */
6054 if (retval && retval != result)
6055 retval = build (INIT_EXPR, TREE_TYPE (result), result, retval);
6061 /* Returns nonzero if the pointer-type FROM can be converted to the
6062 pointer-type TO via a qualification conversion. If CONSTP is -1,
6063 then we return nonzero if the pointers are similar, and the
6064 cv-qualification signature of FROM is a proper subset of that of TO.
6066 If CONSTP is positive, then all outer pointers have been
6070 comp_ptr_ttypes_real (tree to, tree from, int constp)
6072 bool to_more_cv_qualified = false;
6074 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6076 if (TREE_CODE (to) != TREE_CODE (from))
6079 if (TREE_CODE (from) == OFFSET_TYPE
6080 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6081 TYPE_OFFSET_BASETYPE (to)))
6084 /* Const and volatile mean something different for function types,
6085 so the usual checks are not appropriate. */
6086 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6088 if (!at_least_as_qualified_p (to, from))
6091 if (!at_least_as_qualified_p (from, to))
6095 to_more_cv_qualified = true;
6099 constp &= TYPE_READONLY (to);
6102 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6103 return ((constp >= 0 || to_more_cv_qualified)
6104 && same_type_ignoring_top_level_qualifiers_p (to, from));
6108 /* When comparing, say, char ** to char const **, this function takes
6109 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6110 types to this function. */
6113 comp_ptr_ttypes (tree to, tree from)
6115 return comp_ptr_ttypes_real (to, from, 1);
6118 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6119 type or inheritance-related types, regardless of cv-quals. */
6122 ptr_reasonably_similar (tree to, tree from)
6124 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6126 /* Any target type is similar enough to void. */
6127 if (TREE_CODE (to) == VOID_TYPE
6128 || TREE_CODE (from) == VOID_TYPE)
6131 if (TREE_CODE (to) != TREE_CODE (from))
6134 if (TREE_CODE (from) == OFFSET_TYPE
6135 && comptypes (TYPE_OFFSET_BASETYPE (to),
6136 TYPE_OFFSET_BASETYPE (from),
6137 COMPARE_BASE | COMPARE_DERIVED))
6140 if (TREE_CODE (to) == INTEGER_TYPE
6141 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6144 if (TREE_CODE (to) == FUNCTION_TYPE)
6147 if (TREE_CODE (to) != POINTER_TYPE)
6149 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6150 COMPARE_BASE | COMPARE_DERIVED);
6154 /* Like comp_ptr_ttypes, for const_cast. */
6157 comp_ptr_ttypes_const (tree to, tree from)
6159 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6161 if (TREE_CODE (to) != TREE_CODE (from))
6164 if (TREE_CODE (from) == OFFSET_TYPE
6165 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6166 TYPE_OFFSET_BASETYPE (to)))
6169 if (TREE_CODE (to) != POINTER_TYPE)
6170 return same_type_ignoring_top_level_qualifiers_p (to, from);
6174 /* Returns the type qualifiers for this type, including the qualifiers on the
6175 elements for an array type. */
6178 cp_type_quals (tree type)
6180 type = strip_array_types (type);
6181 if (type == error_mark_node)
6182 return TYPE_UNQUALIFIED;
6183 return TYPE_QUALS (type);
6186 /* Returns nonzero if the TYPE contains a mutable member. */
6189 cp_has_mutable_p (tree type)
6191 type = strip_array_types (type);
6193 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6196 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6197 exemplar types such that casting T1 to T2 is casting away castness
6198 if and only if there is no implicit conversion from T1 to T2. */
6201 casts_away_constness_r (tree *t1, tree *t2)
6206 /* [expr.const.cast]
6208 For multi-level pointer to members and multi-level mixed pointers
6209 and pointers to members (conv.qual), the "member" aspect of a
6210 pointer to member level is ignored when determining if a const
6211 cv-qualifier has been cast away. */
6212 if (TYPE_PTRMEM_P (*t1))
6213 *t1 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t1));
6214 if (TYPE_PTRMEM_P (*t2))
6215 *t2 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t2));
6217 /* [expr.const.cast]
6219 For two pointer types:
6221 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6222 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6225 casting from X1 to X2 casts away constness if, for a non-pointer
6226 type T there does not exist an implicit conversion (clause
6229 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6233 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6235 if (TREE_CODE (*t1) != POINTER_TYPE
6236 || TREE_CODE (*t2) != POINTER_TYPE)
6238 *t1 = cp_build_qualified_type (void_type_node,
6239 cp_type_quals (*t1));
6240 *t2 = cp_build_qualified_type (void_type_node,
6241 cp_type_quals (*t2));
6245 quals1 = cp_type_quals (*t1);
6246 quals2 = cp_type_quals (*t2);
6247 *t1 = TREE_TYPE (*t1);
6248 *t2 = TREE_TYPE (*t2);
6249 casts_away_constness_r (t1, t2);
6250 *t1 = build_pointer_type (*t1);
6251 *t2 = build_pointer_type (*t2);
6252 *t1 = cp_build_qualified_type (*t1, quals1);
6253 *t2 = cp_build_qualified_type (*t2, quals2);
6256 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6260 casts_away_constness (tree t1, tree t2)
6262 if (TREE_CODE (t2) == REFERENCE_TYPE)
6264 /* [expr.const.cast]
6266 Casting from an lvalue of type T1 to an lvalue of type T2
6267 using a reference cast casts away constness if a cast from an
6268 rvalue of type "pointer to T1" to the type "pointer to T2"
6269 casts away constness. */
6270 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6271 return casts_away_constness (build_pointer_type (t1),
6272 build_pointer_type (TREE_TYPE (t2)));
6275 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6276 /* [expr.const.cast]
6278 Casting from an rvalue of type "pointer to data member of X
6279 of type T1" to the type "pointer to data member of Y of type
6280 T2" casts away constness if a cast from an rvalue of type
6281 "pointer to T1" to the type "pointer to T2" casts away
6283 return casts_away_constness
6284 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6285 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6287 /* Casting away constness is only something that makes sense for
6288 pointer or reference types. */
6289 if (TREE_CODE (t1) != POINTER_TYPE
6290 || TREE_CODE (t2) != POINTER_TYPE)
6293 /* Top-level qualifiers don't matter. */
6294 t1 = TYPE_MAIN_VARIANT (t1);
6295 t2 = TYPE_MAIN_VARIANT (t2);
6296 casts_away_constness_r (&t1, &t2);
6297 if (!can_convert (t2, t1))
6303 /* If T is a REFERENCE_TYPE return the type to which T refers.
6304 Otherwise, return T itself. */
6307 non_reference (tree t)
6309 if (TREE_CODE (t) == REFERENCE_TYPE)