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, 2005 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, 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, 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. */
31 #include "coretypes.h"
41 #include "diagnostic.h"
46 static tree
pfn_from_ptrmemfunc (tree
);
47 static tree
convert_for_assignment (tree
, tree
, const char *, tree
, int);
48 static tree
cp_pointer_int_sum (enum tree_code
, tree
, tree
);
49 static tree
rationalize_conditional_expr (enum tree_code
, tree
);
50 static int comp_ptr_ttypes_real (tree
, tree
, int);
51 static bool comp_except_types (tree
, tree
, bool);
52 static bool comp_array_types (tree
, tree
, bool);
53 static tree
common_base_type (tree
, tree
);
54 static tree
pointer_diff (tree
, tree
, tree
);
55 static tree
get_delta_difference (tree
, tree
, bool, bool);
56 static void casts_away_constness_r (tree
*, tree
*);
57 static bool casts_away_constness (tree
, tree
);
58 static void maybe_warn_about_returning_address_of_local (tree
);
59 static tree
lookup_destructor (tree
, tree
, tree
);
60 static tree
convert_arguments (tree
, tree
, tree
, int);
62 /* Do `exp = require_complete_type (exp);' to make sure exp
63 does not have an incomplete type. (That includes void types.)
64 Returns the error_mark_node if the VALUE does not have
65 complete type when this function returns. */
68 require_complete_type (tree value
)
72 if (processing_template_decl
|| value
== error_mark_node
)
75 if (TREE_CODE (value
) == OVERLOAD
)
76 type
= unknown_type_node
;
78 type
= TREE_TYPE (value
);
80 if (type
== error_mark_node
)
81 return error_mark_node
;
83 /* First, detect a valid value with a complete type. */
84 if (COMPLETE_TYPE_P (type
))
87 if (complete_type_or_else (type
, value
))
90 return error_mark_node
;
93 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
94 a template instantiation, do the instantiation. Returns TYPE,
95 whether or not it could be completed, unless something goes
96 horribly wrong, in which case the error_mark_node is returned. */
99 complete_type (tree type
)
101 if (type
== NULL_TREE
)
102 /* Rather than crash, we return something sure to cause an error
104 return error_mark_node
;
106 if (type
== error_mark_node
|| COMPLETE_TYPE_P (type
))
108 else if (TREE_CODE (type
) == ARRAY_TYPE
&& TYPE_DOMAIN (type
))
110 tree t
= complete_type (TREE_TYPE (type
));
111 unsigned int needs_constructing
, has_nontrivial_dtor
;
112 if (COMPLETE_TYPE_P (t
) && !dependent_type_p (type
))
115 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t
));
117 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t
));
118 for (t
= TYPE_MAIN_VARIANT (type
); t
; t
= TYPE_NEXT_VARIANT (t
))
120 TYPE_NEEDS_CONSTRUCTING (t
) = needs_constructing
;
121 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t
) = has_nontrivial_dtor
;
124 else if (CLASS_TYPE_P (type
) && CLASSTYPE_TEMPLATE_INSTANTIATION (type
))
125 instantiate_class_template (TYPE_MAIN_VARIANT (type
));
130 /* Like complete_type, but issue an error if the TYPE cannot be completed.
131 VALUE is used for informative diagnostics.
132 Returns NULL_TREE if the type cannot be made complete. */
135 complete_type_or_else (tree type
, tree value
)
137 type
= complete_type (type
);
138 if (type
== error_mark_node
)
139 /* We already issued an error. */
141 else if (!COMPLETE_TYPE_P (type
))
143 cxx_incomplete_type_diagnostic (value
, type
, 0);
150 /* Return truthvalue of whether type of EXP is instantiated. */
153 type_unknown_p (tree exp
)
155 return (TREE_CODE (exp
) == TREE_LIST
156 || TREE_TYPE (exp
) == unknown_type_node
);
160 /* Return the common type of two parameter lists.
161 We assume that comptypes has already been done and returned 1;
162 if that isn't so, this may crash.
164 As an optimization, free the space we allocate if the parameter
165 lists are already common. */
168 commonparms (tree p1
, tree p2
)
170 tree oldargs
= p1
, newargs
, n
;
174 len
= list_length (p1
);
175 newargs
= tree_last (p1
);
177 if (newargs
== void_list_node
)
186 newargs
= tree_cons (NULL_TREE
, NULL_TREE
, newargs
);
191 p1
= TREE_CHAIN (p1
), p2
= TREE_CHAIN (p2
), n
= TREE_CHAIN (n
), i
++)
193 if (TREE_PURPOSE (p1
) && !TREE_PURPOSE (p2
))
195 TREE_PURPOSE (n
) = TREE_PURPOSE (p1
);
198 else if (! TREE_PURPOSE (p1
))
200 if (TREE_PURPOSE (p2
))
202 TREE_PURPOSE (n
) = TREE_PURPOSE (p2
);
208 if (1 != simple_cst_equal (TREE_PURPOSE (p1
), TREE_PURPOSE (p2
)))
210 TREE_PURPOSE (n
) = TREE_PURPOSE (p2
);
212 if (TREE_VALUE (p1
) != TREE_VALUE (p2
))
215 TREE_VALUE (n
) = merge_types (TREE_VALUE (p1
), TREE_VALUE (p2
));
218 TREE_VALUE (n
) = TREE_VALUE (p1
);
226 /* Given a type, perhaps copied for a typedef,
227 find the "original" version of it. */
229 original_type (tree t
)
231 while (TYPE_NAME (t
) != NULL_TREE
)
233 tree x
= TYPE_NAME (t
);
234 if (TREE_CODE (x
) != TYPE_DECL
)
236 x
= DECL_ORIGINAL_TYPE (x
);
244 /* T1 and T2 are arithmetic or enumeration types. Return the type
245 that will result from the "usual arithmetic conversions" on T1 and
246 T2 as described in [expr]. */
249 type_after_usual_arithmetic_conversions (tree t1
, tree t2
)
251 enum tree_code code1
= TREE_CODE (t1
);
252 enum tree_code code2
= TREE_CODE (t2
);
255 /* FIXME: Attributes. */
256 gcc_assert (ARITHMETIC_TYPE_P (t1
)
257 || TREE_CODE (t1
) == COMPLEX_TYPE
258 || TREE_CODE (t1
) == VECTOR_TYPE
259 || TREE_CODE (t1
) == ENUMERAL_TYPE
);
260 gcc_assert (ARITHMETIC_TYPE_P (t2
)
261 || TREE_CODE (t2
) == COMPLEX_TYPE
262 || TREE_CODE (t1
) == VECTOR_TYPE
263 || TREE_CODE (t2
) == ENUMERAL_TYPE
);
265 /* In what follows, we slightly generalize the rules given in [expr] so
266 as to deal with `long long' and `complex'. First, merge the
268 attributes
= (*targetm
.merge_type_attributes
) (t1
, t2
);
270 /* If one type is complex, form the common type of the non-complex
271 components, then make that complex. Use T1 or T2 if it is the
273 if (code1
== COMPLEX_TYPE
|| code2
== COMPLEX_TYPE
)
275 tree subtype1
= code1
== COMPLEX_TYPE
? TREE_TYPE (t1
) : t1
;
276 tree subtype2
= code2
== COMPLEX_TYPE
? TREE_TYPE (t2
) : t2
;
278 = type_after_usual_arithmetic_conversions (subtype1
, subtype2
);
280 if (code1
== COMPLEX_TYPE
&& TREE_TYPE (t1
) == subtype
)
281 return build_type_attribute_variant (t1
, attributes
);
282 else if (code2
== COMPLEX_TYPE
&& TREE_TYPE (t2
) == subtype
)
283 return build_type_attribute_variant (t2
, attributes
);
285 return build_type_attribute_variant (build_complex_type (subtype
),
289 if (code1
== VECTOR_TYPE
)
291 /* When we get here we should have two vectors of the same size.
292 Just prefer the unsigned one if present. */
293 if (TYPE_UNSIGNED (t1
))
294 return build_type_attribute_variant (t1
, attributes
);
296 return build_type_attribute_variant (t2
, attributes
);
299 /* If only one is real, use it as the result. */
300 if (code1
== REAL_TYPE
&& code2
!= REAL_TYPE
)
301 return build_type_attribute_variant (t1
, attributes
);
302 if (code2
== REAL_TYPE
&& code1
!= REAL_TYPE
)
303 return build_type_attribute_variant (t2
, attributes
);
305 /* Perform the integral promotions. */
306 if (code1
!= REAL_TYPE
)
308 t1
= type_promotes_to (t1
);
309 t2
= type_promotes_to (t2
);
312 /* Both real or both integers; use the one with greater precision. */
313 if (TYPE_PRECISION (t1
) > TYPE_PRECISION (t2
))
314 return build_type_attribute_variant (t1
, attributes
);
315 else if (TYPE_PRECISION (t2
) > TYPE_PRECISION (t1
))
316 return build_type_attribute_variant (t2
, attributes
);
318 /* The types are the same; no need to do anything fancy. */
319 if (TYPE_MAIN_VARIANT (t1
) == TYPE_MAIN_VARIANT (t2
))
320 return build_type_attribute_variant (t1
, attributes
);
322 if (code1
!= REAL_TYPE
)
324 /* If one is a sizetype, use it so size_binop doesn't blow up. */
325 if (TYPE_IS_SIZETYPE (t1
) > TYPE_IS_SIZETYPE (t2
))
326 return build_type_attribute_variant (t1
, attributes
);
327 if (TYPE_IS_SIZETYPE (t2
) > TYPE_IS_SIZETYPE (t1
))
328 return build_type_attribute_variant (t2
, attributes
);
330 /* If one is unsigned long long, then convert the other to unsigned
332 if (same_type_p (TYPE_MAIN_VARIANT (t1
), long_long_unsigned_type_node
)
333 || same_type_p (TYPE_MAIN_VARIANT (t2
), long_long_unsigned_type_node
))
334 return build_type_attribute_variant (long_long_unsigned_type_node
,
336 /* If one is a long long, and the other is an unsigned long, and
337 long long can represent all the values of an unsigned long, then
338 convert to a long long. Otherwise, convert to an unsigned long
339 long. Otherwise, if either operand is long long, convert the
342 Since we're here, we know the TYPE_PRECISION is the same;
343 therefore converting to long long cannot represent all the values
344 of an unsigned long, so we choose unsigned long long in that
346 if (same_type_p (TYPE_MAIN_VARIANT (t1
), long_long_integer_type_node
)
347 || same_type_p (TYPE_MAIN_VARIANT (t2
), long_long_integer_type_node
))
349 tree t
= ((TYPE_UNSIGNED (t1
) || TYPE_UNSIGNED (t2
))
350 ? long_long_unsigned_type_node
351 : long_long_integer_type_node
);
352 return build_type_attribute_variant (t
, attributes
);
355 /* Go through the same procedure, but for longs. */
356 if (same_type_p (TYPE_MAIN_VARIANT (t1
), long_unsigned_type_node
)
357 || same_type_p (TYPE_MAIN_VARIANT (t2
), long_unsigned_type_node
))
358 return build_type_attribute_variant (long_unsigned_type_node
,
360 if (same_type_p (TYPE_MAIN_VARIANT (t1
), long_integer_type_node
)
361 || same_type_p (TYPE_MAIN_VARIANT (t2
), long_integer_type_node
))
363 tree t
= ((TYPE_UNSIGNED (t1
) || TYPE_UNSIGNED (t2
))
364 ? long_unsigned_type_node
: long_integer_type_node
);
365 return build_type_attribute_variant (t
, attributes
);
367 /* Otherwise prefer the unsigned one. */
368 if (TYPE_UNSIGNED (t1
))
369 return build_type_attribute_variant (t1
, attributes
);
371 return build_type_attribute_variant (t2
, attributes
);
375 if (same_type_p (TYPE_MAIN_VARIANT (t1
), long_double_type_node
)
376 || same_type_p (TYPE_MAIN_VARIANT (t2
), long_double_type_node
))
377 return build_type_attribute_variant (long_double_type_node
,
379 if (same_type_p (TYPE_MAIN_VARIANT (t1
), double_type_node
)
380 || same_type_p (TYPE_MAIN_VARIANT (t2
), double_type_node
))
381 return build_type_attribute_variant (double_type_node
,
383 if (same_type_p (TYPE_MAIN_VARIANT (t1
), float_type_node
)
384 || same_type_p (TYPE_MAIN_VARIANT (t2
), float_type_node
))
385 return build_type_attribute_variant (float_type_node
,
388 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
389 the standard C++ floating-point types. Logic earlier in this
390 function has already eliminated the possibility that
391 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
392 compelling reason to choose one or the other. */
393 return build_type_attribute_variant (t1
, attributes
);
397 /* Subroutine of composite_pointer_type to implement the recursive
398 case. See that function for documentation fo the parameters. */
401 composite_pointer_type_r (tree t1
, tree t2
, const char* location
)
408 /* Determine the types pointed to by T1 and T2. */
409 if (TREE_CODE (t1
) == POINTER_TYPE
)
411 pointee1
= TREE_TYPE (t1
);
412 pointee2
= TREE_TYPE (t2
);
416 pointee1
= TYPE_PTRMEM_POINTED_TO_TYPE (t1
);
417 pointee2
= TYPE_PTRMEM_POINTED_TO_TYPE (t2
);
422 Otherwise, the composite pointer type is a pointer type
423 similar (_conv.qual_) to the type of one of the operands,
424 with a cv-qualification signature (_conv.qual_) that is the
425 union of the cv-qualification signatures of the operand
427 if (same_type_ignoring_top_level_qualifiers_p (pointee1
, pointee2
))
428 result_type
= pointee1
;
429 else if ((TREE_CODE (pointee1
) == POINTER_TYPE
430 && TREE_CODE (pointee2
) == POINTER_TYPE
)
431 || (TYPE_PTR_TO_MEMBER_P (pointee1
)
432 && TYPE_PTR_TO_MEMBER_P (pointee2
)))
433 result_type
= composite_pointer_type_r (pointee1
, pointee2
, location
);
436 pedwarn ("%s between distinct pointer types %qT and %qT "
439 result_type
= void_type_node
;
441 result_type
= cp_build_qualified_type (result_type
,
442 (cp_type_quals (pointee1
)
443 | cp_type_quals (pointee2
)));
444 /* If the original types were pointers to members, so is the
446 if (TYPE_PTR_TO_MEMBER_P (t1
))
448 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1
),
449 TYPE_PTRMEM_CLASS_TYPE (t2
)))
450 pedwarn ("%s between distinct pointer types %qT and %qT "
453 result_type
= build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1
),
457 result_type
= build_pointer_type (result_type
);
459 /* Merge the attributes. */
460 attributes
= (*targetm
.merge_type_attributes
) (t1
, t2
);
461 return build_type_attribute_variant (result_type
, attributes
);
464 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
465 ARG1 and ARG2 are the values with those types. The LOCATION is a
466 string describing the current location, in case an error occurs.
468 This routine also implements the computation of a common type for
469 pointers-to-members as per [expr.eq]. */
472 composite_pointer_type (tree t1
, tree t2
, tree arg1
, tree arg2
,
473 const char* location
)
480 If one operand is a null pointer constant, the composite pointer
481 type is the type of the other operand. */
482 if (null_ptr_cst_p (arg1
))
484 if (null_ptr_cst_p (arg2
))
491 If one of the operands has type "pointer to cv1 void*", then
492 the other has type "pointer to cv2T", and the composite pointer
493 type is "pointer to cv12 void", where cv12 is the union of cv1
496 If either type is a pointer to void, make sure it is T1. */
497 if (TREE_CODE (t2
) == POINTER_TYPE
&& VOID_TYPE_P (TREE_TYPE (t2
)))
505 /* Now, if T1 is a pointer to void, merge the qualifiers. */
506 if (TREE_CODE (t1
) == POINTER_TYPE
&& VOID_TYPE_P (TREE_TYPE (t1
)))
511 if (pedantic
&& TYPE_PTRFN_P (t2
))
512 pedwarn ("ISO C++ forbids %s between pointer of type %<void *%> "
513 "and pointer-to-function", location
);
515 = cp_build_qualified_type (void_type_node
,
516 (cp_type_quals (TREE_TYPE (t1
))
517 | cp_type_quals (TREE_TYPE (t2
))));
518 result_type
= build_pointer_type (result_type
);
519 /* Merge the attributes. */
520 attributes
= (*targetm
.merge_type_attributes
) (t1
, t2
);
521 return build_type_attribute_variant (result_type
, attributes
);
524 if (c_dialect_objc () && TREE_CODE (t1
) == POINTER_TYPE
525 && TREE_CODE (t2
) == POINTER_TYPE
)
527 if (objc_compare_types (t1
, t2
, -3, NULL_TREE
))
531 /* [expr.eq] permits the application of a pointer conversion to
532 bring the pointers to a common type. */
533 if (TREE_CODE (t1
) == POINTER_TYPE
&& TREE_CODE (t2
) == POINTER_TYPE
534 && CLASS_TYPE_P (TREE_TYPE (t1
))
535 && CLASS_TYPE_P (TREE_TYPE (t2
))
536 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1
),
539 class1
= TREE_TYPE (t1
);
540 class2
= TREE_TYPE (t2
);
542 if (DERIVED_FROM_P (class1
, class2
))
543 t2
= (build_pointer_type
544 (cp_build_qualified_type (class1
, TYPE_QUALS (class2
))));
545 else if (DERIVED_FROM_P (class2
, class1
))
546 t1
= (build_pointer_type
547 (cp_build_qualified_type (class2
, TYPE_QUALS (class1
))));
550 error ("%s between distinct pointer types %qT and %qT "
551 "lacks a cast", location
, t1
, t2
);
552 return error_mark_node
;
555 /* [expr.eq] permits the application of a pointer-to-member
556 conversion to change the class type of one of the types. */
557 else if (TYPE_PTR_TO_MEMBER_P (t1
)
558 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1
),
559 TYPE_PTRMEM_CLASS_TYPE (t2
)))
561 class1
= TYPE_PTRMEM_CLASS_TYPE (t1
);
562 class2
= TYPE_PTRMEM_CLASS_TYPE (t2
);
564 if (DERIVED_FROM_P (class1
, class2
))
565 t1
= build_ptrmem_type (class2
, TYPE_PTRMEM_POINTED_TO_TYPE (t1
));
566 else if (DERIVED_FROM_P (class2
, class1
))
567 t2
= build_ptrmem_type (class1
, TYPE_PTRMEM_POINTED_TO_TYPE (t2
));
570 error ("%s between distinct pointer-to-member types %qT and %qT "
571 "lacks a cast", location
, t1
, t2
);
572 return error_mark_node
;
576 return composite_pointer_type_r (t1
, t2
, location
);
579 /* Return the merged type of two types.
580 We assume that comptypes has already been done and returned 1;
581 if that isn't so, this may crash.
583 This just combines attributes and default arguments; any other
584 differences would cause the two types to compare unalike. */
587 merge_types (tree t1
, tree t2
)
589 enum tree_code code1
;
590 enum tree_code code2
;
593 /* Save time if the two types are the same. */
596 if (original_type (t1
) == original_type (t2
))
599 /* If one type is nonsense, use the other. */
600 if (t1
== error_mark_node
)
602 if (t2
== error_mark_node
)
605 /* Merge the attributes. */
606 attributes
= (*targetm
.merge_type_attributes
) (t1
, t2
);
608 if (TYPE_PTRMEMFUNC_P (t1
))
609 t1
= TYPE_PTRMEMFUNC_FN_TYPE (t1
);
610 if (TYPE_PTRMEMFUNC_P (t2
))
611 t2
= TYPE_PTRMEMFUNC_FN_TYPE (t2
);
613 code1
= TREE_CODE (t1
);
614 code2
= TREE_CODE (t2
);
620 /* For two pointers, do this recursively on the target type. */
622 tree target
= merge_types (TREE_TYPE (t1
), TREE_TYPE (t2
));
623 int quals
= cp_type_quals (t1
);
625 if (code1
== POINTER_TYPE
)
626 t1
= build_pointer_type (target
);
628 t1
= build_reference_type (target
);
629 t1
= build_type_attribute_variant (t1
, attributes
);
630 t1
= cp_build_qualified_type (t1
, quals
);
632 if (TREE_CODE (target
) == METHOD_TYPE
)
633 t1
= build_ptrmemfunc_type (t1
);
642 quals
= cp_type_quals (t1
);
643 pointee
= merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1
),
644 TYPE_PTRMEM_POINTED_TO_TYPE (t2
));
645 t1
= build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1
),
647 t1
= cp_build_qualified_type (t1
, quals
);
653 tree elt
= merge_types (TREE_TYPE (t1
), TREE_TYPE (t2
));
654 /* Save space: see if the result is identical to one of the args. */
655 if (elt
== TREE_TYPE (t1
) && TYPE_DOMAIN (t1
))
656 return build_type_attribute_variant (t1
, attributes
);
657 if (elt
== TREE_TYPE (t2
) && TYPE_DOMAIN (t2
))
658 return build_type_attribute_variant (t2
, attributes
);
659 /* Merge the element types, and have a size if either arg has one. */
660 t1
= build_cplus_array_type
661 (elt
, TYPE_DOMAIN (TYPE_DOMAIN (t1
) ? t1
: t2
));
666 /* Function types: prefer the one that specified arg types.
667 If both do, merge the arg types. Also merge the return types. */
669 tree valtype
= merge_types (TREE_TYPE (t1
), TREE_TYPE (t2
));
670 tree p1
= TYPE_ARG_TYPES (t1
);
671 tree p2
= TYPE_ARG_TYPES (t2
);
674 /* Save space: see if the result is identical to one of the args. */
675 if (valtype
== TREE_TYPE (t1
) && ! p2
)
676 return cp_build_type_attribute_variant (t1
, attributes
);
677 if (valtype
== TREE_TYPE (t2
) && ! p1
)
678 return cp_build_type_attribute_variant (t2
, attributes
);
680 /* Simple way if one arg fails to specify argument types. */
681 if (p1
== NULL_TREE
|| TREE_VALUE (p1
) == void_type_node
)
683 rval
= build_function_type (valtype
, p2
);
684 if ((raises
= TYPE_RAISES_EXCEPTIONS (t2
)))
685 rval
= build_exception_variant (rval
, raises
);
686 return cp_build_type_attribute_variant (rval
, attributes
);
688 raises
= TYPE_RAISES_EXCEPTIONS (t1
);
689 if (p2
== NULL_TREE
|| TREE_VALUE (p2
) == void_type_node
)
691 rval
= build_function_type (valtype
, p1
);
693 rval
= build_exception_variant (rval
, raises
);
694 return cp_build_type_attribute_variant (rval
, attributes
);
697 rval
= build_function_type (valtype
, commonparms (p1
, p2
));
698 t1
= build_exception_variant (rval
, raises
);
704 /* Get this value the long way, since TYPE_METHOD_BASETYPE
705 is just the main variant of this. */
706 tree basetype
= TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2
)));
707 tree raises
= TYPE_RAISES_EXCEPTIONS (t1
);
710 /* If this was a member function type, get back to the
711 original type of type member function (i.e., without
712 the class instance variable up front. */
713 t1
= build_function_type (TREE_TYPE (t1
),
714 TREE_CHAIN (TYPE_ARG_TYPES (t1
)));
715 t2
= build_function_type (TREE_TYPE (t2
),
716 TREE_CHAIN (TYPE_ARG_TYPES (t2
)));
717 t3
= merge_types (t1
, t2
);
718 t3
= build_method_type_directly (basetype
, TREE_TYPE (t3
),
719 TYPE_ARG_TYPES (t3
));
720 t1
= build_exception_variant (t3
, raises
);
725 /* There is no need to merge attributes into a TYPENAME_TYPE.
726 When the type is instantiated it will have whatever
727 attributes result from the instantiation. */
732 return cp_build_type_attribute_variant (t1
, attributes
);
735 /* Return the common type of two types.
736 We assume that comptypes has already been done and returned 1;
737 if that isn't so, this may crash.
739 This is the type for the result of most arithmetic operations
740 if the operands have the given two types. */
743 common_type (tree t1
, tree t2
)
745 enum tree_code code1
;
746 enum tree_code code2
;
748 /* If one type is nonsense, bail. */
749 if (t1
== error_mark_node
|| t2
== error_mark_node
)
750 return error_mark_node
;
752 code1
= TREE_CODE (t1
);
753 code2
= TREE_CODE (t2
);
755 if ((ARITHMETIC_TYPE_P (t1
) || code1
== ENUMERAL_TYPE
756 || code1
== COMPLEX_TYPE
|| code1
== VECTOR_TYPE
)
757 && (ARITHMETIC_TYPE_P (t2
) || code2
== ENUMERAL_TYPE
758 || code2
== COMPLEX_TYPE
|| code2
== VECTOR_TYPE
))
759 return type_after_usual_arithmetic_conversions (t1
, t2
);
761 else if ((TYPE_PTR_P (t1
) && TYPE_PTR_P (t2
))
762 || (TYPE_PTRMEM_P (t1
) && TYPE_PTRMEM_P (t2
))
763 || (TYPE_PTRMEMFUNC_P (t1
) && TYPE_PTRMEMFUNC_P (t2
)))
764 return composite_pointer_type (t1
, t2
, error_mark_node
, error_mark_node
,
770 /* Compare two exception specifier types for exactness or subsetness, if
771 allowed. Returns false for mismatch, true for match (same, or
774 [except.spec] "If a class X ... objects of class X or any class publicly
775 and unambiguously derived from X. Similarly, if a pointer type Y * ...
776 exceptions of type Y * or that are pointers to any type publicly and
777 unambiguously derived from Y. Otherwise a function only allows exceptions
778 that have the same type ..."
779 This does not mention cv qualifiers and is different to what throw
780 [except.throw] and catch [except.catch] will do. They will ignore the
781 top level cv qualifiers, and allow qualifiers in the pointer to class
784 We implement the letter of the standard. */
787 comp_except_types (tree a
, tree b
, bool exact
)
789 if (same_type_p (a
, b
))
793 if (cp_type_quals (a
) || cp_type_quals (b
))
796 if (TREE_CODE (a
) == POINTER_TYPE
797 && TREE_CODE (b
) == POINTER_TYPE
)
801 if (cp_type_quals (a
) || cp_type_quals (b
))
805 if (TREE_CODE (a
) != RECORD_TYPE
806 || TREE_CODE (b
) != RECORD_TYPE
)
809 if (PUBLICLY_UNIQUELY_DERIVED_P (a
, b
))
815 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
816 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
817 otherwise it must be exact. Exception lists are unordered, but
818 we've already filtered out duplicates. Most lists will be in order,
819 we should try to make use of that. */
822 comp_except_specs (tree t1
, tree t2
, bool exact
)
831 if (t1
== NULL_TREE
) /* T1 is ... */
832 return t2
== NULL_TREE
|| !exact
;
833 if (!TREE_VALUE (t1
)) /* t1 is EMPTY */
834 return t2
!= NULL_TREE
&& !TREE_VALUE (t2
);
835 if (t2
== NULL_TREE
) /* T2 is ... */
837 if (TREE_VALUE (t1
) && !TREE_VALUE (t2
)) /* T2 is EMPTY, T1 is not */
840 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
841 Count how many we find, to determine exactness. For exact matching and
842 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
844 for (base
= t1
; t2
!= NULL_TREE
; t2
= TREE_CHAIN (t2
))
846 for (probe
= base
; probe
!= NULL_TREE
; probe
= TREE_CHAIN (probe
))
848 tree a
= TREE_VALUE (probe
);
849 tree b
= TREE_VALUE (t2
);
851 if (comp_except_types (a
, b
, exact
))
853 if (probe
== base
&& exact
)
854 base
= TREE_CHAIN (probe
);
859 if (probe
== NULL_TREE
)
862 return !exact
|| base
== NULL_TREE
|| length
== list_length (t1
);
865 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
866 [] can match [size]. */
869 comp_array_types (tree t1
, tree t2
, bool allow_redeclaration
)
878 /* The type of the array elements must be the same. */
879 if (!same_type_p (TREE_TYPE (t1
), TREE_TYPE (t2
)))
882 d1
= TYPE_DOMAIN (t1
);
883 d2
= TYPE_DOMAIN (t2
);
888 /* If one of the arrays is dimensionless, and the other has a
889 dimension, they are of different types. However, it is valid to
897 declarations for an array object can specify
898 array types that differ by the presence or absence of a major
899 array bound (_dcl.array_). */
901 return allow_redeclaration
;
903 /* Check that the dimensions are the same. */
905 if (!cp_tree_equal (TYPE_MIN_VALUE (d1
), TYPE_MIN_VALUE (d2
)))
907 max1
= TYPE_MAX_VALUE (d1
);
908 max2
= TYPE_MAX_VALUE (d2
);
909 if (processing_template_decl
&& !abi_version_at_least (2)
910 && !value_dependent_expression_p (max1
)
911 && !value_dependent_expression_p (max2
))
913 /* With abi-1 we do not fold non-dependent array bounds, (and
914 consequently mangle them incorrectly). We must therefore
915 fold them here, to verify the domains have the same
921 if (!cp_tree_equal (max1
, max2
))
927 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
928 is a bitwise-or of the COMPARE_* flags. */
931 comptypes (tree t1
, tree t2
, int strict
)
936 /* Suppress errors caused by previously reported errors. */
937 if (t1
== error_mark_node
|| t2
== error_mark_node
)
940 gcc_assert (TYPE_P (t1
) && TYPE_P (t2
));
942 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
943 current instantiation. */
944 if (TREE_CODE (t1
) == TYPENAME_TYPE
)
946 tree resolved
= resolve_typename_type (t1
, /*only_current_p=*/true);
948 if (resolved
!= error_mark_node
)
952 if (TREE_CODE (t2
) == TYPENAME_TYPE
)
954 tree resolved
= resolve_typename_type (t2
, /*only_current_p=*/true);
956 if (resolved
!= error_mark_node
)
960 /* If either type is the internal version of sizetype, use the
962 if (TREE_CODE (t1
) == INTEGER_TYPE
&& TYPE_IS_SIZETYPE (t1
)
963 && TYPE_ORIG_SIZE_TYPE (t1
))
964 t1
= TYPE_ORIG_SIZE_TYPE (t1
);
966 if (TREE_CODE (t2
) == INTEGER_TYPE
&& TYPE_IS_SIZETYPE (t2
)
967 && TYPE_ORIG_SIZE_TYPE (t2
))
968 t2
= TYPE_ORIG_SIZE_TYPE (t2
);
970 if (TYPE_PTRMEMFUNC_P (t1
))
971 t1
= TYPE_PTRMEMFUNC_FN_TYPE (t1
);
972 if (TYPE_PTRMEMFUNC_P (t2
))
973 t2
= TYPE_PTRMEMFUNC_FN_TYPE (t2
);
975 /* Different classes of types can't be compatible. */
976 if (TREE_CODE (t1
) != TREE_CODE (t2
))
979 /* Qualifiers must match. For array types, we will check when we
980 recur on the array element types. */
981 if (TREE_CODE (t1
) != ARRAY_TYPE
982 && TYPE_QUALS (t1
) != TYPE_QUALS (t2
))
984 if (TYPE_FOR_JAVA (t1
) != TYPE_FOR_JAVA (t2
))
987 /* Allow for two different type nodes which have essentially the same
988 definition. Note that we already checked for equality of the type
989 qualifiers (just above). */
991 if (TREE_CODE (t1
) != ARRAY_TYPE
992 && TYPE_MAIN_VARIANT (t1
) == TYPE_MAIN_VARIANT (t2
))
995 /* Compare the types. Break out if they could be the same. */
996 switch (TREE_CODE (t1
))
998 case TEMPLATE_TEMPLATE_PARM
:
999 case BOUND_TEMPLATE_TEMPLATE_PARM
:
1000 if (TEMPLATE_TYPE_IDX (t1
) != TEMPLATE_TYPE_IDX (t2
)
1001 || TEMPLATE_TYPE_LEVEL (t1
) != TEMPLATE_TYPE_LEVEL (t2
))
1003 if (!comp_template_parms
1004 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1
)),
1005 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2
))))
1007 if (TREE_CODE (t1
) == TEMPLATE_TEMPLATE_PARM
)
1009 /* Don't check inheritance. */
1010 strict
= COMPARE_STRICT
;
1015 if (TYPE_TEMPLATE_INFO (t1
) && TYPE_TEMPLATE_INFO (t2
)
1016 && (TYPE_TI_TEMPLATE (t1
) == TYPE_TI_TEMPLATE (t2
)
1017 || TREE_CODE (t1
) == BOUND_TEMPLATE_TEMPLATE_PARM
)
1018 && comp_template_args (TYPE_TI_ARGS (t1
), TYPE_TI_ARGS (t2
)))
1021 if ((strict
& COMPARE_BASE
) && DERIVED_FROM_P (t1
, t2
))
1023 else if ((strict
& COMPARE_DERIVED
) && DERIVED_FROM_P (t2
, t1
))
1029 if (!comptypes (TYPE_OFFSET_BASETYPE (t1
), TYPE_OFFSET_BASETYPE (t2
),
1030 strict
& ~COMPARE_REDECLARATION
))
1032 if (!same_type_p (TREE_TYPE (t1
), TREE_TYPE (t2
)))
1037 case REFERENCE_TYPE
:
1038 if (TYPE_MODE (t1
) != TYPE_MODE (t2
)
1039 || TYPE_REF_CAN_ALIAS_ALL (t1
) != TYPE_REF_CAN_ALIAS_ALL (t2
)
1040 || !same_type_p (TREE_TYPE (t1
), TREE_TYPE (t2
)))
1046 if (!same_type_p (TREE_TYPE (t1
), TREE_TYPE (t2
)))
1048 if (!compparms (TYPE_ARG_TYPES (t1
), TYPE_ARG_TYPES (t2
)))
1053 /* Target types must match incl. qualifiers. */
1054 if (!comp_array_types (t1
, t2
, !!(strict
& COMPARE_REDECLARATION
)))
1058 case TEMPLATE_TYPE_PARM
:
1059 if (TEMPLATE_TYPE_IDX (t1
) != TEMPLATE_TYPE_IDX (t2
)
1060 || TEMPLATE_TYPE_LEVEL (t1
) != TEMPLATE_TYPE_LEVEL (t2
))
1065 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1
),
1066 TYPENAME_TYPE_FULLNAME (t2
)))
1068 if (!same_type_p (TYPE_CONTEXT (t1
), TYPE_CONTEXT (t2
)))
1072 case UNBOUND_CLASS_TEMPLATE
:
1073 if (!cp_tree_equal (TYPE_IDENTIFIER (t1
), TYPE_IDENTIFIER (t2
)))
1075 if (!same_type_p (TYPE_CONTEXT (t1
), TYPE_CONTEXT (t2
)))
1080 if (!same_type_p (TREE_TYPE (t1
), TREE_TYPE (t2
)))
1085 if (TYPE_VECTOR_SUBPARTS (t1
) != TYPE_VECTOR_SUBPARTS (t2
)
1086 || !same_type_p (TREE_TYPE (t1
), TREE_TYPE (t2
)))
1094 /* If we get here, we know that from a target independent POV the
1095 types are the same. Make sure the target attributes are also
1097 return targetm
.comp_type_attributes (t1
, t2
);
1100 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1103 at_least_as_qualified_p (tree type1
, tree type2
)
1105 int q1
= cp_type_quals (type1
);
1106 int q2
= cp_type_quals (type2
);
1108 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1109 return (q1
& q2
) == q2
;
1112 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1113 more cv-qualified that TYPE1, and 0 otherwise. */
1116 comp_cv_qualification (tree type1
, tree type2
)
1118 int q1
= cp_type_quals (type1
);
1119 int q2
= cp_type_quals (type2
);
1124 if ((q1
& q2
) == q2
)
1126 else if ((q1
& q2
) == q1
)
1132 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1133 subset of the cv-qualification signature of TYPE2, and the types
1134 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1137 comp_cv_qual_signature (tree type1
, tree type2
)
1139 if (comp_ptr_ttypes_real (type2
, type1
, -1))
1141 else if (comp_ptr_ttypes_real (type1
, type2
, -1))
1147 /* If two types share a common base type, return that basetype.
1148 If there is not a unique most-derived base type, this function
1149 returns ERROR_MARK_NODE. */
1152 common_base_type (tree tt1
, tree tt2
)
1154 tree best
= NULL_TREE
;
1157 /* If one is a baseclass of another, that's good enough. */
1158 if (UNIQUELY_DERIVED_FROM_P (tt1
, tt2
))
1160 if (UNIQUELY_DERIVED_FROM_P (tt2
, tt1
))
1163 /* Otherwise, try to find a unique baseclass of TT1
1164 that is shared by TT2, and follow that down. */
1165 for (i
= BINFO_N_BASE_BINFOS (TYPE_BINFO (tt1
))-1; i
>= 0; i
--)
1167 tree basetype
= BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt1
), i
));
1168 tree trial
= common_base_type (basetype
, tt2
);
1172 if (trial
== error_mark_node
)
1174 if (best
== NULL_TREE
)
1176 else if (best
!= trial
)
1177 return error_mark_node
;
1182 for (i
= BINFO_N_BASE_BINFOS (TYPE_BINFO (tt2
))-1; i
>= 0; i
--)
1184 tree basetype
= BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt2
), i
));
1185 tree trial
= common_base_type (tt1
, basetype
);
1189 if (trial
== error_mark_node
)
1191 if (best
== NULL_TREE
)
1193 else if (best
!= trial
)
1194 return error_mark_node
;
1200 /* Subroutines of `comptypes'. */
1202 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1203 equivalent in the sense that functions with those parameter types
1204 can have equivalent types. The two lists must be equivalent,
1205 element by element. */
1208 compparms (tree parms1
, tree parms2
)
1212 /* An unspecified parmlist matches any specified parmlist
1213 whose argument types don't need default promotions. */
1215 for (t1
= parms1
, t2
= parms2
;
1217 t1
= TREE_CHAIN (t1
), t2
= TREE_CHAIN (t2
))
1219 /* If one parmlist is shorter than the other,
1220 they fail to match. */
1223 if (!same_type_p (TREE_VALUE (t1
), TREE_VALUE (t2
)))
1230 /* Process a sizeof or alignof expression where the operand is a
1234 cxx_sizeof_or_alignof_type (tree type
, enum tree_code op
, bool complain
)
1236 enum tree_code type_code
;
1238 const char *op_name
;
1240 gcc_assert (op
== SIZEOF_EXPR
|| op
== ALIGNOF_EXPR
);
1241 if (type
== error_mark_node
)
1242 return error_mark_node
;
1244 if (dependent_type_p (type
))
1246 value
= build_min (op
, size_type_node
, type
);
1247 TREE_READONLY (value
) = 1;
1251 op_name
= operator_name_info
[(int) op
].name
;
1253 type
= non_reference (type
);
1254 type_code
= TREE_CODE (type
);
1256 if (type_code
== METHOD_TYPE
)
1258 if (complain
&& (pedantic
|| warn_pointer_arith
))
1259 pedwarn ("invalid application of %qs to a member function", op_name
);
1260 value
= size_one_node
;
1263 value
= c_sizeof_or_alignof_type (complete_type (type
),
1270 /* Process a sizeof expression where the operand is an expression. */
1273 cxx_sizeof_expr (tree e
)
1275 if (e
== error_mark_node
)
1276 return error_mark_node
;
1278 if (processing_template_decl
)
1280 e
= build_min (SIZEOF_EXPR
, size_type_node
, e
);
1281 TREE_SIDE_EFFECTS (e
) = 0;
1282 TREE_READONLY (e
) = 1;
1287 if (TREE_CODE (e
) == COMPONENT_REF
1288 && TREE_CODE (TREE_OPERAND (e
, 1)) == FIELD_DECL
1289 && DECL_C_BIT_FIELD (TREE_OPERAND (e
, 1)))
1291 error ("invalid application of %<sizeof%> to a bit-field");
1294 else if (is_overloaded_fn (e
))
1296 pedwarn ("ISO C++ forbids applying %<sizeof%> to an expression of "
1300 else if (type_unknown_p (e
))
1302 cxx_incomplete_type_error (e
, TREE_TYPE (e
));
1308 return cxx_sizeof_or_alignof_type (e
, SIZEOF_EXPR
, true);
1311 /* Implement the __alignof keyword: Return the minimum required
1312 alignment of E, measured in bytes. For VAR_DECL's and
1313 FIELD_DECL's return DECL_ALIGN (which can be set from an
1314 "aligned" __attribute__ specification). */
1317 cxx_alignof_expr (tree e
)
1321 if (e
== error_mark_node
)
1322 return error_mark_node
;
1324 if (processing_template_decl
)
1326 e
= build_min (ALIGNOF_EXPR
, size_type_node
, e
);
1327 TREE_SIDE_EFFECTS (e
) = 0;
1328 TREE_READONLY (e
) = 1;
1333 if (TREE_CODE (e
) == VAR_DECL
)
1334 t
= size_int (DECL_ALIGN_UNIT (e
));
1335 else if (TREE_CODE (e
) == COMPONENT_REF
1336 && TREE_CODE (TREE_OPERAND (e
, 1)) == FIELD_DECL
1337 && DECL_C_BIT_FIELD (TREE_OPERAND (e
, 1)))
1339 error ("invalid application of %<__alignof%> to a bit-field");
1342 else if (TREE_CODE (e
) == COMPONENT_REF
1343 && TREE_CODE (TREE_OPERAND (e
, 1)) == FIELD_DECL
)
1344 t
= size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e
, 1)));
1345 else if (is_overloaded_fn (e
))
1347 pedwarn ("ISO C++ forbids applying %<__alignof%> to an expression of "
1351 else if (type_unknown_p (e
))
1353 cxx_incomplete_type_error (e
, TREE_TYPE (e
));
1357 return cxx_sizeof_or_alignof_type (TREE_TYPE (e
), ALIGNOF_EXPR
, true);
1359 return fold_convert (size_type_node
, t
);
1362 /* Process a sizeof or alignof expression E with code OP where the operand
1363 is an expression. */
1366 cxx_sizeof_or_alignof_expr (tree e
, enum tree_code op
)
1368 if (op
== SIZEOF_EXPR
)
1369 return cxx_sizeof_expr (e
);
1371 return cxx_alignof_expr (e
);
1374 /* EXPR is being used in a context that is not a function call.
1379 The expression can be used only as the left-hand operand of a
1380 member function call.
1382 [expr.mptr.operator]
1384 If the result of .* or ->* is a function, then that result can be
1385 used only as the operand for the function call operator ().
1387 by issuing an error message if appropriate. Returns true iff EXPR
1388 violates these rules. */
1391 invalid_nonstatic_memfn_p (tree expr
)
1393 if (TREE_CODE (TREE_TYPE (expr
)) == METHOD_TYPE
)
1395 error ("invalid use of non-static member function");
1401 /* If EXP is a reference to a bitfield, and the type of EXP does not
1402 match the declared type of the bitfield, return the declared type
1403 of the bitfield. Otherwise, return NULL_TREE. */
1406 is_bitfield_expr_with_lowered_type (tree exp
)
1410 if (TREE_CODE (exp
) == COND_EXPR
)
1412 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp
, 1)))
1414 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp
, 2));
1416 if (TREE_CODE (exp
) != COMPONENT_REF
)
1418 field
= TREE_OPERAND (exp
, 1);
1419 if (TREE_CODE (field
) != FIELD_DECL
|| !DECL_C_BIT_FIELD (field
))
1421 if (same_type_ignoring_top_level_qualifiers_p
1422 (TREE_TYPE (exp
), DECL_BIT_FIELD_TYPE (field
)))
1424 return DECL_BIT_FIELD_TYPE (field
);
1427 /* Perform the conversions in [expr] that apply when an lvalue appears
1428 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1429 function-to-pointer conversions. In addition, manifest constants
1430 are replaced by their values, and bitfield references are converted
1431 to their declared types.
1433 Although the returned value is being used as an rvalue, this
1434 function does not wrap the returned expression in a
1435 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1436 that the return value is no longer an lvalue. */
1439 decay_conversion (tree exp
)
1442 enum tree_code code
;
1444 type
= TREE_TYPE (exp
);
1445 if (type
== error_mark_node
)
1446 return error_mark_node
;
1448 if (type_unknown_p (exp
))
1450 cxx_incomplete_type_error (exp
, TREE_TYPE (exp
));
1451 return error_mark_node
;
1454 exp
= decl_constant_value (exp
);
1455 if (error_operand_p (exp
))
1456 return error_mark_node
;
1458 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1459 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1460 code
= TREE_CODE (type
);
1461 if (code
== VOID_TYPE
)
1463 error ("void value not ignored as it ought to be");
1464 return error_mark_node
;
1466 if (invalid_nonstatic_memfn_p (exp
))
1467 return error_mark_node
;
1468 if (code
== FUNCTION_TYPE
|| is_overloaded_fn (exp
))
1469 return build_unary_op (ADDR_EXPR
, exp
, 0);
1470 if (code
== ARRAY_TYPE
)
1475 if (TREE_CODE (exp
) == INDIRECT_REF
)
1476 return build_nop (build_pointer_type (TREE_TYPE (type
)),
1477 TREE_OPERAND (exp
, 0));
1479 if (TREE_CODE (exp
) == COMPOUND_EXPR
)
1481 tree op1
= decay_conversion (TREE_OPERAND (exp
, 1));
1482 return build2 (COMPOUND_EXPR
, TREE_TYPE (op1
),
1483 TREE_OPERAND (exp
, 0), op1
);
1487 && ! (TREE_CODE (exp
) == CONSTRUCTOR
&& TREE_STATIC (exp
)))
1489 error ("invalid use of non-lvalue array");
1490 return error_mark_node
;
1493 ptrtype
= build_pointer_type (TREE_TYPE (type
));
1495 if (TREE_CODE (exp
) == VAR_DECL
)
1497 if (!cxx_mark_addressable (exp
))
1498 return error_mark_node
;
1499 adr
= build_nop (ptrtype
, build_address (exp
));
1502 /* This way is better for a COMPONENT_REF since it can
1503 simplify the offset for a component. */
1504 adr
= build_unary_op (ADDR_EXPR
, exp
, 1);
1505 return cp_convert (ptrtype
, adr
);
1508 /* If a bitfield is used in a context where integral promotion
1509 applies, then the caller is expected to have used
1510 default_conversion. That function promotes bitfields correctly
1511 before calling this function. At this point, if we have a
1512 bitfield referenced, we may assume that is not subject to
1513 promotion, and that, therefore, the type of the resulting rvalue
1514 is the declared type of the bitfield. */
1515 exp
= convert_bitfield_to_declared_type (exp
);
1517 /* We do not call rvalue() here because we do not want to wrap EXP
1518 in a NON_LVALUE_EXPR. */
1522 Non-class rvalues always have cv-unqualified types. */
1523 type
= TREE_TYPE (exp
);
1524 if (!CLASS_TYPE_P (type
) && cp_type_quals (type
))
1525 exp
= build_nop (TYPE_MAIN_VARIANT (type
), exp
);
1530 /* Perform prepatory conversions, as part of the "usual arithmetic
1531 conversions". In particular, as per [expr]:
1533 Whenever an lvalue expression appears as an operand of an
1534 operator that expects the rvalue for that operand, the
1535 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
1536 standard conversions are applied to convert the expression to an
1539 In addition, we perform integral promotions here, as those are
1540 applied to both operands to a binary operator before determining
1541 what additional conversions should apply. */
1544 default_conversion (tree exp
)
1546 /* Perform the integral promotions first so that bitfield
1547 expressions (which may promote to "int", even if the bitfield is
1548 declared "unsigned") are promoted correctly. */
1549 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp
)))
1550 exp
= perform_integral_promotions (exp
);
1551 /* Perform the other conversions. */
1552 exp
= decay_conversion (exp
);
1557 /* EXPR is an expression with an integral or enumeration type.
1558 Perform the integral promotions in [conv.prom], and return the
1562 perform_integral_promotions (tree expr
)
1569 If the bitfield has an enumerated type, it is treated as any
1570 other value of that type for promotion purposes. */
1571 type
= is_bitfield_expr_with_lowered_type (expr
);
1572 if (!type
|| TREE_CODE (type
) != ENUMERAL_TYPE
)
1573 type
= TREE_TYPE (expr
);
1574 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type
));
1575 promoted_type
= type_promotes_to (type
);
1576 if (type
!= promoted_type
)
1577 expr
= cp_convert (promoted_type
, expr
);
1581 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1585 inline_conversion (tree exp
)
1587 if (TREE_CODE (exp
) == FUNCTION_DECL
)
1588 exp
= build1 (ADDR_EXPR
, build_pointer_type (TREE_TYPE (exp
)), exp
);
1593 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1594 decay_conversion to one. */
1597 string_conv_p (tree totype
, tree exp
, int warn
)
1601 if (TREE_CODE (totype
) != POINTER_TYPE
)
1604 t
= TREE_TYPE (totype
);
1605 if (!same_type_p (t
, char_type_node
)
1606 && !same_type_p (t
, wchar_type_node
))
1609 if (TREE_CODE (exp
) == STRING_CST
)
1611 /* Make sure that we don't try to convert between char and wchar_t. */
1612 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp
))), t
))
1617 /* Is this a string constant which has decayed to 'const char *'? */
1618 t
= build_pointer_type (build_qualified_type (t
, TYPE_QUAL_CONST
));
1619 if (!same_type_p (TREE_TYPE (exp
), t
))
1622 if (TREE_CODE (exp
) != ADDR_EXPR
1623 || TREE_CODE (TREE_OPERAND (exp
, 0)) != STRING_CST
)
1627 /* This warning is not very useful, as it complains about printf. */
1629 warning (OPT_Wwrite_strings
, "deprecated conversion from string constant to %qT'", totype
);
1634 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1635 can, for example, use as an lvalue. This code used to be in
1636 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1637 expressions, where we're dealing with aggregates. But now it's again only
1638 called from unary_complex_lvalue. The case (in particular) that led to
1639 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1643 rationalize_conditional_expr (enum tree_code code
, tree t
)
1645 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1646 the first operand is always the one to be used if both operands
1647 are equal, so we know what conditional expression this used to be. */
1648 if (TREE_CODE (t
) == MIN_EXPR
|| TREE_CODE (t
) == MAX_EXPR
)
1650 /* The following code is incorrect if either operand side-effects. */
1651 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 0))
1652 && !TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 1)));
1654 build_conditional_expr (build_x_binary_op ((TREE_CODE (t
) == MIN_EXPR
1655 ? LE_EXPR
: GE_EXPR
),
1656 TREE_OPERAND (t
, 0),
1657 TREE_OPERAND (t
, 1),
1658 /*overloaded_p=*/NULL
),
1659 build_unary_op (code
, TREE_OPERAND (t
, 0), 0),
1660 build_unary_op (code
, TREE_OPERAND (t
, 1), 0));
1664 build_conditional_expr (TREE_OPERAND (t
, 0),
1665 build_unary_op (code
, TREE_OPERAND (t
, 1), 0),
1666 build_unary_op (code
, TREE_OPERAND (t
, 2), 0));
1669 /* Given the TYPE of an anonymous union field inside T, return the
1670 FIELD_DECL for the field. If not found return NULL_TREE. Because
1671 anonymous unions can nest, we must also search all anonymous unions
1672 that are directly reachable. */
1675 lookup_anon_field (tree t
, tree type
)
1679 for (field
= TYPE_FIELDS (t
); field
; field
= TREE_CHAIN (field
))
1681 if (TREE_STATIC (field
))
1683 if (TREE_CODE (field
) != FIELD_DECL
|| DECL_ARTIFICIAL (field
))
1686 /* If we find it directly, return the field. */
1687 if (DECL_NAME (field
) == NULL_TREE
1688 && type
== TYPE_MAIN_VARIANT (TREE_TYPE (field
)))
1693 /* Otherwise, it could be nested, search harder. */
1694 if (DECL_NAME (field
) == NULL_TREE
1695 && ANON_AGGR_TYPE_P (TREE_TYPE (field
)))
1697 tree subfield
= lookup_anon_field (TREE_TYPE (field
), type
);
1705 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1706 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1707 non-NULL, it indicates the path to the base used to name MEMBER.
1708 If PRESERVE_REFERENCE is true, the expression returned will have
1709 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1710 returned will have the type referred to by the reference.
1712 This function does not perform access control; that is either done
1713 earlier by the parser when the name of MEMBER is resolved to MEMBER
1714 itself, or later when overload resolution selects one of the
1715 functions indicated by MEMBER. */
1718 build_class_member_access_expr (tree object
, tree member
,
1719 tree access_path
, bool preserve_reference
)
1723 tree result
= NULL_TREE
;
1725 if (object
== error_mark_node
|| member
== error_mark_node
)
1726 return error_mark_node
;
1728 gcc_assert (DECL_P (member
) || BASELINK_P (member
));
1732 The type of the first expression shall be "class object" (of a
1734 object_type
= TREE_TYPE (object
);
1735 if (!currently_open_class (object_type
)
1736 && !complete_type_or_else (object_type
, object
))
1737 return error_mark_node
;
1738 if (!CLASS_TYPE_P (object_type
))
1740 error ("request for member %qD in %qE, which is of non-class type %qT",
1741 member
, object
, object_type
);
1742 return error_mark_node
;
1745 /* The standard does not seem to actually say that MEMBER must be a
1746 member of OBJECT_TYPE. However, that is clearly what is
1748 if (DECL_P (member
))
1750 member_scope
= DECL_CLASS_CONTEXT (member
);
1752 if (TREE_DEPRECATED (member
))
1753 warn_deprecated_use (member
);
1756 member_scope
= BINFO_TYPE (BASELINK_BINFO (member
));
1757 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1758 presently be the anonymous union. Go outwards until we find a
1759 type related to OBJECT_TYPE. */
1760 while (ANON_AGGR_TYPE_P (member_scope
)
1761 && !same_type_ignoring_top_level_qualifiers_p (member_scope
,
1763 member_scope
= TYPE_CONTEXT (member_scope
);
1764 if (!member_scope
|| !DERIVED_FROM_P (member_scope
, object_type
))
1766 if (TREE_CODE (member
) == FIELD_DECL
)
1767 error ("invalid use of nonstatic data member %qE", member
);
1769 error ("%qD is not a member of %qT", member
, object_type
);
1770 return error_mark_node
;
1773 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1774 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1775 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1777 tree temp
= unary_complex_lvalue (ADDR_EXPR
, object
);
1779 object
= build_indirect_ref (temp
, NULL
);
1782 /* In [expr.ref], there is an explicit list of the valid choices for
1783 MEMBER. We check for each of those cases here. */
1784 if (TREE_CODE (member
) == VAR_DECL
)
1786 /* A static data member. */
1788 /* If OBJECT has side-effects, they are supposed to occur. */
1789 if (TREE_SIDE_EFFECTS (object
))
1790 result
= build2 (COMPOUND_EXPR
, TREE_TYPE (result
), object
, result
);
1792 else if (TREE_CODE (member
) == FIELD_DECL
)
1794 /* A non-static data member. */
1799 null_object_p
= (TREE_CODE (object
) == INDIRECT_REF
1800 && integer_zerop (TREE_OPERAND (object
, 0)));
1802 /* Convert OBJECT to the type of MEMBER. */
1803 if (!same_type_p (TYPE_MAIN_VARIANT (object_type
),
1804 TYPE_MAIN_VARIANT (member_scope
)))
1809 binfo
= lookup_base (access_path
? access_path
: object_type
,
1810 member_scope
, ba_unique
, &kind
);
1811 if (binfo
== error_mark_node
)
1812 return error_mark_node
;
1814 /* It is invalid to try to get to a virtual base of a
1815 NULL object. The most common cause is invalid use of
1817 if (null_object_p
&& kind
== bk_via_virtual
)
1819 error ("invalid access to non-static data member %qD of "
1822 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
1823 return error_mark_node
;
1826 /* Convert to the base. */
1827 object
= build_base_path (PLUS_EXPR
, object
, binfo
,
1829 /* If we found the base successfully then we should be able
1830 to convert to it successfully. */
1831 gcc_assert (object
!= error_mark_node
);
1834 /* Complain about other invalid uses of offsetof, even though they will
1835 give the right answer. Note that we complain whether or not they
1836 actually used the offsetof macro, since there's no way to know at this
1837 point. So we just give a warning, instead of a pedwarn. */
1838 /* Do not produce this warning for base class field references, because
1839 we know for a fact that didn't come from offsetof. This does occur
1840 in various testsuite cases where a null object is passed where a
1841 vtable access is required. */
1842 if (null_object_p
&& warn_invalid_offsetof
1843 && CLASSTYPE_NON_POD_P (object_type
)
1844 && !DECL_FIELD_IS_BASE (member
)
1845 && !skip_evaluation
)
1847 warning (0, "invalid access to non-static data member %qD of NULL object",
1849 warning (0, "(perhaps the %<offsetof%> macro was used incorrectly)");
1852 /* If MEMBER is from an anonymous aggregate, we have converted
1853 OBJECT so that it refers to the class containing the
1854 anonymous union. Generate a reference to the anonymous union
1855 itself, and recur to find MEMBER. */
1856 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member
))
1857 /* When this code is called from build_field_call, the
1858 object already has the type of the anonymous union.
1859 That is because the COMPONENT_REF was already
1860 constructed, and was then disassembled before calling
1861 build_field_call. After the function-call code is
1862 cleaned up, this waste can be eliminated. */
1863 && (!same_type_ignoring_top_level_qualifiers_p
1864 (TREE_TYPE (object
), DECL_CONTEXT (member
))))
1866 tree anonymous_union
;
1868 anonymous_union
= lookup_anon_field (TREE_TYPE (object
),
1869 DECL_CONTEXT (member
));
1870 object
= build_class_member_access_expr (object
,
1872 /*access_path=*/NULL_TREE
,
1873 preserve_reference
);
1876 /* Compute the type of the field, as described in [expr.ref]. */
1877 type_quals
= TYPE_UNQUALIFIED
;
1878 member_type
= TREE_TYPE (member
);
1879 if (TREE_CODE (member_type
) != REFERENCE_TYPE
)
1881 type_quals
= (cp_type_quals (member_type
)
1882 | cp_type_quals (object_type
));
1884 /* A field is const (volatile) if the enclosing object, or the
1885 field itself, is const (volatile). But, a mutable field is
1886 not const, even within a const object. */
1887 if (DECL_MUTABLE_P (member
))
1888 type_quals
&= ~TYPE_QUAL_CONST
;
1889 member_type
= cp_build_qualified_type (member_type
, type_quals
);
1892 result
= build3 (COMPONENT_REF
, member_type
, object
, member
,
1894 result
= fold_if_not_in_template (result
);
1896 /* Mark the expression const or volatile, as appropriate. Even
1897 though we've dealt with the type above, we still have to mark the
1898 expression itself. */
1899 if (type_quals
& TYPE_QUAL_CONST
)
1900 TREE_READONLY (result
) = 1;
1901 if (type_quals
& TYPE_QUAL_VOLATILE
)
1902 TREE_THIS_VOLATILE (result
) = 1;
1904 else if (BASELINK_P (member
))
1906 /* The member is a (possibly overloaded) member function. */
1910 /* If the MEMBER is exactly one static member function, then we
1911 know the type of the expression. Otherwise, we must wait
1912 until overload resolution has been performed. */
1913 functions
= BASELINK_FUNCTIONS (member
);
1914 if (TREE_CODE (functions
) == FUNCTION_DECL
1915 && DECL_STATIC_FUNCTION_P (functions
))
1916 type
= TREE_TYPE (functions
);
1918 type
= unknown_type_node
;
1919 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1920 base. That will happen when the function is called. */
1921 result
= build3 (COMPONENT_REF
, type
, object
, member
, NULL_TREE
);
1923 else if (TREE_CODE (member
) == CONST_DECL
)
1925 /* The member is an enumerator. */
1927 /* If OBJECT has side-effects, they are supposed to occur. */
1928 if (TREE_SIDE_EFFECTS (object
))
1929 result
= build2 (COMPOUND_EXPR
, TREE_TYPE (result
),
1934 error ("invalid use of %qD", member
);
1935 return error_mark_node
;
1938 if (!preserve_reference
)
1941 If E2 is declared to have type "reference to T", then ... the
1942 type of E1.E2 is T. */
1943 result
= convert_from_reference (result
);
1948 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1949 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1952 lookup_destructor (tree object
, tree scope
, tree dtor_name
)
1954 tree object_type
= TREE_TYPE (object
);
1955 tree dtor_type
= TREE_OPERAND (dtor_name
, 0);
1958 if (scope
&& !check_dtor_name (scope
, dtor_type
))
1960 error ("qualified type %qT does not match destructor name ~%qT",
1962 return error_mark_node
;
1964 if (!DERIVED_FROM_P (dtor_type
, TYPE_MAIN_VARIANT (object_type
)))
1966 error ("the type being destroyed is %qT, but the destructor refers to %qT",
1967 TYPE_MAIN_VARIANT (object_type
), dtor_type
);
1968 return error_mark_node
;
1970 expr
= lookup_member (dtor_type
, complete_dtor_identifier
,
1971 /*protect=*/1, /*want_type=*/false);
1972 expr
= (adjust_result_of_qualified_name_lookup
1973 (expr
, dtor_type
, object_type
));
1977 /* An expression of the form "A::template B" has been resolved to
1978 DECL. Issue a diagnostic if B is not a template or template
1982 check_template_keyword (tree decl
)
1984 /* The standard says:
1988 If a name prefixed by the keyword template is not a member
1989 template, the program is ill-formed.
1991 DR 228 removed the restriction that the template be a member
1994 DR 96, if accepted would add the further restriction that explicit
1995 template arguments must be provided if the template keyword is
1996 used, but, as of 2005-10-16, that DR is still in "drafting". If
1997 this DR is accepted, then the semantic checks here can be
1998 simplified, as the entity named must in fact be a template
1999 specialization, rather than, as at present, a set of overloaded
2000 functions containing at least one template function. */
2001 if (TREE_CODE (decl
) != TEMPLATE_DECL
2002 && TREE_CODE (decl
) != TEMPLATE_ID_EXPR
)
2004 if (!is_overloaded_fn (decl
))
2005 pedwarn ("%qD is not a template", decl
);
2010 if (BASELINK_P (fns
))
2011 fns
= BASELINK_FUNCTIONS (fns
);
2014 tree fn
= OVL_CURRENT (fns
);
2015 if (TREE_CODE (fn
) == TEMPLATE_DECL
2016 || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
2018 if (TREE_CODE (fn
) == FUNCTION_DECL
2019 && DECL_USE_TEMPLATE (fn
)
2020 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
2022 fns
= OVL_NEXT (fns
);
2025 pedwarn ("%qD is not a template", decl
);
2030 /* This function is called by the parser to process a class member
2031 access expression of the form OBJECT.NAME. NAME is a node used by
2032 the parser to represent a name; it is not yet a DECL. It may,
2033 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2034 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2035 there is no reason to do the lookup twice, so the parser keeps the
2036 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2037 be a template via the use of the "A::template B" syntax. */
2040 finish_class_member_access_expr (tree object
, tree name
, bool template_p
)
2045 tree access_path
= NULL_TREE
;
2046 tree orig_object
= object
;
2047 tree orig_name
= name
;
2049 if (object
== error_mark_node
|| name
== error_mark_node
)
2050 return error_mark_node
;
2052 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2053 if (!objc_is_public (object
, name
))
2054 return error_mark_node
;
2056 object_type
= TREE_TYPE (object
);
2058 if (processing_template_decl
)
2060 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2061 dependent_type_p (object_type
)
2062 /* If NAME is just an IDENTIFIER_NODE, then the expression
2064 || TREE_CODE (object
) == IDENTIFIER_NODE
2065 /* If NAME is "f<args>", where either 'f' or 'args' is
2066 dependent, then the expression is dependent. */
2067 || (TREE_CODE (name
) == TEMPLATE_ID_EXPR
2068 && dependent_template_id_p (TREE_OPERAND (name
, 0),
2069 TREE_OPERAND (name
, 1)))
2070 /* If NAME is "T::X" where "T" is dependent, then the
2071 expression is dependent. */
2072 || (TREE_CODE (name
) == SCOPE_REF
2073 && TYPE_P (TREE_OPERAND (name
, 0))
2074 && dependent_type_p (TREE_OPERAND (name
, 0))))
2075 return build_min_nt (COMPONENT_REF
, object
, name
, NULL_TREE
);
2076 object
= build_non_dependent_expr (object
);
2081 The type of the first expression shall be "class object" (of a
2083 if (!currently_open_class (object_type
)
2084 && !complete_type_or_else (object_type
, object
))
2085 return error_mark_node
;
2086 if (!CLASS_TYPE_P (object_type
))
2088 error ("request for member %qD in %qE, which is of non-class type %qT",
2089 name
, object
, object_type
);
2090 return error_mark_node
;
2093 if (BASELINK_P (name
))
2094 /* A member function that has already been looked up. */
2098 bool is_template_id
= false;
2099 tree template_args
= NULL_TREE
;
2102 if (TREE_CODE (name
) == TEMPLATE_ID_EXPR
)
2104 is_template_id
= true;
2105 template_args
= TREE_OPERAND (name
, 1);
2106 name
= TREE_OPERAND (name
, 0);
2108 if (TREE_CODE (name
) == OVERLOAD
)
2109 name
= DECL_NAME (get_first_fn (name
));
2110 else if (DECL_P (name
))
2111 name
= DECL_NAME (name
);
2114 if (TREE_CODE (name
) == SCOPE_REF
)
2116 /* A qualified name. The qualifying class or namespace `S'
2117 has already been looked up; it is either a TYPE or a
2119 scope
= TREE_OPERAND (name
, 0);
2120 name
= TREE_OPERAND (name
, 1);
2122 /* If SCOPE is a namespace, then the qualified name does not
2123 name a member of OBJECT_TYPE. */
2124 if (TREE_CODE (scope
) == NAMESPACE_DECL
)
2126 error ("%<%D::%D%> is not a member of %qT",
2127 scope
, name
, object_type
);
2128 return error_mark_node
;
2131 gcc_assert (CLASS_TYPE_P (scope
));
2132 gcc_assert (TREE_CODE (name
) == IDENTIFIER_NODE
2133 || TREE_CODE (name
) == BIT_NOT_EXPR
);
2135 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2136 access_path
= lookup_base (object_type
, scope
, ba_check
, NULL
);
2137 if (access_path
== error_mark_node
)
2138 return error_mark_node
;
2141 error ("%qT is not a base of %qT", scope
, object_type
);
2142 return error_mark_node
;
2148 access_path
= object_type
;
2151 if (TREE_CODE (name
) == BIT_NOT_EXPR
)
2152 member
= lookup_destructor (object
, scope
, name
);
2155 /* Look up the member. */
2156 member
= lookup_member (access_path
, name
, /*protect=*/1,
2157 /*want_type=*/false);
2158 if (member
== NULL_TREE
)
2160 error ("%qD has no member named %qE", object_type
, name
);
2161 return error_mark_node
;
2163 if (member
== error_mark_node
)
2164 return error_mark_node
;
2169 tree
template = member
;
2171 if (BASELINK_P (template))
2172 template = lookup_template_function (template, template_args
);
2175 error ("%qD is not a member template function", name
);
2176 return error_mark_node
;
2181 if (TREE_DEPRECATED (member
))
2182 warn_deprecated_use (member
);
2185 check_template_keyword (member
);
2187 expr
= build_class_member_access_expr (object
, member
, access_path
,
2188 /*preserve_reference=*/false);
2189 if (processing_template_decl
&& expr
!= error_mark_node
)
2191 if (BASELINK_P (member
))
2193 if (TREE_CODE (orig_name
) == SCOPE_REF
)
2194 BASELINK_QUALIFIED_P (member
) = 1;
2197 return build_min_non_dep (COMPONENT_REF
, expr
,
2198 orig_object
, orig_name
,
2205 /* Return an expression for the MEMBER_NAME field in the internal
2206 representation of PTRMEM, a pointer-to-member function. (Each
2207 pointer-to-member function type gets its own RECORD_TYPE so it is
2208 more convenient to access the fields by name than by FIELD_DECL.)
2209 This routine converts the NAME to a FIELD_DECL and then creates the
2210 node for the complete expression. */
2213 build_ptrmemfunc_access_expr (tree ptrmem
, tree member_name
)
2219 /* This code is a stripped down version of
2220 build_class_member_access_expr. It does not work to use that
2221 routine directly because it expects the object to be of class
2223 ptrmem_type
= TREE_TYPE (ptrmem
);
2224 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type
));
2225 member
= lookup_member (ptrmem_type
, member_name
, /*protect=*/0,
2226 /*want_type=*/false);
2227 member_type
= cp_build_qualified_type (TREE_TYPE (member
),
2228 cp_type_quals (ptrmem_type
));
2229 return fold_build3 (COMPONENT_REF
, member_type
,
2230 ptrmem
, member
, NULL_TREE
);
2233 /* Given an expression PTR for a pointer, return an expression
2234 for the value pointed to.
2235 ERRORSTRING is the name of the operator to appear in error messages.
2237 This function may need to overload OPERATOR_FNNAME.
2238 Must also handle REFERENCE_TYPEs for C++. */
2241 build_x_indirect_ref (tree expr
, const char *errorstring
)
2243 tree orig_expr
= expr
;
2246 if (processing_template_decl
)
2248 if (type_dependent_expression_p (expr
))
2249 return build_min_nt (INDIRECT_REF
, expr
);
2250 expr
= build_non_dependent_expr (expr
);
2253 rval
= build_new_op (INDIRECT_REF
, LOOKUP_NORMAL
, expr
, NULL_TREE
,
2254 NULL_TREE
, /*overloaded_p=*/NULL
);
2256 rval
= build_indirect_ref (expr
, errorstring
);
2258 if (processing_template_decl
&& rval
!= error_mark_node
)
2259 return build_min_non_dep (INDIRECT_REF
, rval
, orig_expr
);
2265 build_indirect_ref (tree ptr
, const char *errorstring
)
2269 if (ptr
== error_mark_node
)
2270 return error_mark_node
;
2272 if (ptr
== current_class_ptr
)
2273 return current_class_ref
;
2275 pointer
= (TREE_CODE (TREE_TYPE (ptr
)) == REFERENCE_TYPE
2276 ? ptr
: decay_conversion (ptr
));
2277 type
= TREE_TYPE (pointer
);
2279 if (POINTER_TYPE_P (type
))
2283 If the type of the expression is "pointer to T," the type
2284 of the result is "T."
2286 We must use the canonical variant because certain parts of
2287 the back end, like fold, do pointer comparisons between
2289 tree t
= canonical_type_variant (TREE_TYPE (type
));
2291 if (VOID_TYPE_P (t
))
2293 /* A pointer to incomplete type (other than cv void) can be
2294 dereferenced [expr.unary.op]/1 */
2295 error ("%qT is not a pointer-to-object type", type
);
2296 return error_mark_node
;
2298 else if (TREE_CODE (pointer
) == ADDR_EXPR
2299 && same_type_p (t
, TREE_TYPE (TREE_OPERAND (pointer
, 0))))
2300 /* The POINTER was something like `&x'. We simplify `*&x' to
2302 return TREE_OPERAND (pointer
, 0);
2305 tree ref
= build1 (INDIRECT_REF
, t
, pointer
);
2307 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2308 so that we get the proper error message if the result is used
2309 to assign to. Also, &* is supposed to be a no-op. */
2310 TREE_READONLY (ref
) = CP_TYPE_CONST_P (t
);
2311 TREE_THIS_VOLATILE (ref
) = CP_TYPE_VOLATILE_P (t
);
2312 TREE_SIDE_EFFECTS (ref
)
2313 = (TREE_THIS_VOLATILE (ref
) || TREE_SIDE_EFFECTS (pointer
));
2317 /* `pointer' won't be an error_mark_node if we were given a
2318 pointer to member, so it's cool to check for this here. */
2319 else if (TYPE_PTR_TO_MEMBER_P (type
))
2320 error ("invalid use of %qs on pointer to member", errorstring
);
2321 else if (pointer
!= error_mark_node
)
2324 error ("invalid type argument of %qs", errorstring
);
2326 error ("invalid type argument");
2328 return error_mark_node
;
2331 /* This handles expressions of the form "a[i]", which denotes
2334 This is logically equivalent in C to *(a+i), but we may do it differently.
2335 If A is a variable or a member, we generate a primitive ARRAY_REF.
2336 This avoids forcing the array out of registers, and can work on
2337 arrays that are not lvalues (for example, members of structures returned
2340 If INDEX is of some user-defined type, it must be converted to
2341 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2342 will inherit the type of the array, which will be some pointer type. */
2345 build_array_ref (tree array
, tree idx
)
2349 error ("subscript missing in array reference");
2350 return error_mark_node
;
2353 if (TREE_TYPE (array
) == error_mark_node
2354 || TREE_TYPE (idx
) == error_mark_node
)
2355 return error_mark_node
;
2357 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2359 switch (TREE_CODE (array
))
2363 tree value
= build_array_ref (TREE_OPERAND (array
, 1), idx
);
2364 return build2 (COMPOUND_EXPR
, TREE_TYPE (value
),
2365 TREE_OPERAND (array
, 0), value
);
2369 return build_conditional_expr
2370 (TREE_OPERAND (array
, 0),
2371 build_array_ref (TREE_OPERAND (array
, 1), idx
),
2372 build_array_ref (TREE_OPERAND (array
, 2), idx
));
2378 if (TREE_CODE (TREE_TYPE (array
)) == ARRAY_TYPE
)
2382 warn_array_subscript_with_type_char (idx
);
2384 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx
)))
2386 error ("array subscript is not an integer");
2387 return error_mark_node
;
2390 /* Apply integral promotions *after* noticing character types.
2391 (It is unclear why we do these promotions -- the standard
2392 does not say that we should. In fact, the natural thing would
2393 seem to be to convert IDX to ptrdiff_t; we're performing
2394 pointer arithmetic.) */
2395 idx
= perform_integral_promotions (idx
);
2397 /* An array that is indexed by a non-constant
2398 cannot be stored in a register; we must be able to do
2399 address arithmetic on its address.
2400 Likewise an array of elements of variable size. */
2401 if (TREE_CODE (idx
) != INTEGER_CST
2402 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array
)))
2403 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array
))))
2406 if (!cxx_mark_addressable (array
))
2407 return error_mark_node
;
2410 /* An array that is indexed by a constant value which is not within
2411 the array bounds cannot be stored in a register either; because we
2412 would get a crash in store_bit_field/extract_bit_field when trying
2413 to access a non-existent part of the register. */
2414 if (TREE_CODE (idx
) == INTEGER_CST
2415 && TYPE_DOMAIN (TREE_TYPE (array
))
2416 && ! int_fits_type_p (idx
, TYPE_DOMAIN (TREE_TYPE (array
))))
2418 if (!cxx_mark_addressable (array
))
2419 return error_mark_node
;
2422 if (pedantic
&& !lvalue_p (array
))
2423 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2425 /* Note in C++ it is valid to subscript a `register' array, since
2426 it is valid to take the address of something with that
2427 storage specification. */
2431 while (TREE_CODE (foo
) == COMPONENT_REF
)
2432 foo
= TREE_OPERAND (foo
, 0);
2433 if (TREE_CODE (foo
) == VAR_DECL
&& DECL_REGISTER (foo
))
2434 warning (OPT_Wextra
, "subscripting array declared %<register%>");
2437 type
= TREE_TYPE (TREE_TYPE (array
));
2438 rval
= build4 (ARRAY_REF
, type
, array
, idx
, NULL_TREE
, NULL_TREE
);
2439 /* Array ref is const/volatile if the array elements are
2440 or if the array is.. */
2441 TREE_READONLY (rval
)
2442 |= (CP_TYPE_CONST_P (type
) | TREE_READONLY (array
));
2443 TREE_SIDE_EFFECTS (rval
)
2444 |= (CP_TYPE_VOLATILE_P (type
) | TREE_SIDE_EFFECTS (array
));
2445 TREE_THIS_VOLATILE (rval
)
2446 |= (CP_TYPE_VOLATILE_P (type
) | TREE_THIS_VOLATILE (array
));
2447 return require_complete_type (fold_if_not_in_template (rval
));
2451 tree ar
= default_conversion (array
);
2452 tree ind
= default_conversion (idx
);
2454 /* Put the integer in IND to simplify error checking. */
2455 if (TREE_CODE (TREE_TYPE (ar
)) == INTEGER_TYPE
)
2462 if (ar
== error_mark_node
)
2465 if (TREE_CODE (TREE_TYPE (ar
)) != POINTER_TYPE
)
2467 error ("subscripted value is neither array nor pointer");
2468 return error_mark_node
;
2470 if (TREE_CODE (TREE_TYPE (ind
)) != INTEGER_TYPE
)
2472 error ("array subscript is not an integer");
2473 return error_mark_node
;
2476 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR
, ar
, ind
),
2481 /* Resolve a pointer to member function. INSTANCE is the object
2482 instance to use, if the member points to a virtual member.
2484 This used to avoid checking for virtual functions if basetype
2485 has no virtual functions, according to an earlier ANSI draft.
2486 With the final ISO C++ rules, such an optimization is
2487 incorrect: A pointer to a derived member can be static_cast
2488 to pointer-to-base-member, as long as the dynamic object
2489 later has the right member. */
2492 get_member_function_from_ptrfunc (tree
*instance_ptrptr
, tree function
)
2494 if (TREE_CODE (function
) == OFFSET_REF
)
2495 function
= TREE_OPERAND (function
, 1);
2497 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function
)))
2499 tree idx
, delta
, e1
, e2
, e3
, vtbl
, basetype
;
2500 tree fntype
= TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function
));
2502 tree instance_ptr
= *instance_ptrptr
;
2503 tree instance_save_expr
= 0;
2504 if (instance_ptr
== error_mark_node
)
2506 if (TREE_CODE (function
) == PTRMEM_CST
)
2508 /* Extracting the function address from a pmf is only
2509 allowed with -Wno-pmf-conversions. It only works for
2511 e1
= build_addr_func (PTRMEM_CST_MEMBER (function
));
2512 e1
= convert (fntype
, e1
);
2517 error ("object missing in use of %qE", function
);
2518 return error_mark_node
;
2522 if (TREE_SIDE_EFFECTS (instance_ptr
))
2523 instance_ptr
= instance_save_expr
= save_expr (instance_ptr
);
2525 if (TREE_SIDE_EFFECTS (function
))
2526 function
= save_expr (function
);
2528 /* Start by extracting all the information from the PMF itself. */
2529 e3
= pfn_from_ptrmemfunc (function
);
2530 delta
= build_ptrmemfunc_access_expr (function
, delta_identifier
);
2531 idx
= build1 (NOP_EXPR
, vtable_index_type
, e3
);
2532 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION
)
2534 case ptrmemfunc_vbit_in_pfn
:
2535 e1
= cp_build_binary_op (BIT_AND_EXPR
, idx
, integer_one_node
);
2536 idx
= cp_build_binary_op (MINUS_EXPR
, idx
, integer_one_node
);
2539 case ptrmemfunc_vbit_in_delta
:
2540 e1
= cp_build_binary_op (BIT_AND_EXPR
, delta
, integer_one_node
);
2541 delta
= cp_build_binary_op (RSHIFT_EXPR
, delta
, integer_one_node
);
2548 /* Convert down to the right base before using the instance. A
2549 special case is that in a pointer to member of class C, C may
2550 be incomplete. In that case, the function will of course be
2551 a member of C, and no conversion is required. In fact,
2552 lookup_base will fail in that case, because incomplete
2553 classes do not have BINFOs. */
2554 basetype
= TYPE_METHOD_BASETYPE (TREE_TYPE (fntype
));
2555 if (!same_type_ignoring_top_level_qualifiers_p
2556 (basetype
, TREE_TYPE (TREE_TYPE (instance_ptr
))))
2558 basetype
= lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr
)),
2559 basetype
, ba_check
, NULL
);
2560 instance_ptr
= build_base_path (PLUS_EXPR
, instance_ptr
, basetype
,
2562 if (instance_ptr
== error_mark_node
)
2563 return error_mark_node
;
2565 /* ...and then the delta in the PMF. */
2566 instance_ptr
= build2 (PLUS_EXPR
, TREE_TYPE (instance_ptr
),
2567 instance_ptr
, delta
);
2569 /* Hand back the adjusted 'this' argument to our caller. */
2570 *instance_ptrptr
= instance_ptr
;
2572 /* Next extract the vtable pointer from the object. */
2573 vtbl
= build1 (NOP_EXPR
, build_pointer_type (vtbl_ptr_type_node
),
2575 vtbl
= build_indirect_ref (vtbl
, NULL
);
2577 /* Finally, extract the function pointer from the vtable. */
2578 e2
= fold_build2 (PLUS_EXPR
, TREE_TYPE (vtbl
), vtbl
, idx
);
2579 e2
= build_indirect_ref (e2
, NULL
);
2580 TREE_CONSTANT (e2
) = 1;
2581 TREE_INVARIANT (e2
) = 1;
2583 /* When using function descriptors, the address of the
2584 vtable entry is treated as a function pointer. */
2585 if (TARGET_VTABLE_USES_DESCRIPTORS
)
2586 e2
= build1 (NOP_EXPR
, TREE_TYPE (e2
),
2587 build_unary_op (ADDR_EXPR
, e2
, /*noconvert=*/1));
2589 TREE_TYPE (e2
) = TREE_TYPE (e3
);
2590 e1
= build_conditional_expr (e1
, e2
, e3
);
2592 /* Make sure this doesn't get evaluated first inside one of the
2593 branches of the COND_EXPR. */
2594 if (instance_save_expr
)
2595 e1
= build2 (COMPOUND_EXPR
, TREE_TYPE (e1
),
2596 instance_save_expr
, e1
);
2604 build_function_call (tree function
, tree params
)
2606 tree fntype
, fndecl
;
2607 tree coerced_params
;
2608 tree name
= NULL_TREE
;
2610 tree original
= function
;
2612 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2613 expressions, like those used for ObjC messenger dispatches. */
2614 function
= objc_rewrite_function_call (function
, params
);
2616 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2617 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2618 if (TREE_CODE (function
) == NOP_EXPR
2619 && TREE_TYPE (function
) == TREE_TYPE (TREE_OPERAND (function
, 0)))
2620 function
= TREE_OPERAND (function
, 0);
2622 if (TREE_CODE (function
) == FUNCTION_DECL
)
2624 name
= DECL_NAME (function
);
2626 mark_used (function
);
2629 /* Convert anything with function type to a pointer-to-function. */
2630 if (pedantic
&& DECL_MAIN_P (function
))
2631 pedwarn ("ISO C++ forbids calling %<::main%> from within program");
2633 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2634 (because calling an inline function does not mean the function
2635 needs to be separately compiled). */
2637 if (DECL_INLINE (function
))
2638 function
= inline_conversion (function
);
2640 function
= build_addr_func (function
);
2646 function
= build_addr_func (function
);
2649 if (function
== error_mark_node
)
2650 return error_mark_node
;
2652 fntype
= TREE_TYPE (function
);
2654 if (TYPE_PTRMEMFUNC_P (fntype
))
2656 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2657 "function in %<%E (...)%>",
2659 return error_mark_node
;
2662 is_method
= (TREE_CODE (fntype
) == POINTER_TYPE
2663 && TREE_CODE (TREE_TYPE (fntype
)) == METHOD_TYPE
);
2665 if (!((TREE_CODE (fntype
) == POINTER_TYPE
2666 && TREE_CODE (TREE_TYPE (fntype
)) == FUNCTION_TYPE
)
2668 || TREE_CODE (function
) == TEMPLATE_ID_EXPR
))
2670 error ("%qE cannot be used as a function", original
);
2671 return error_mark_node
;
2674 /* fntype now gets the type of function pointed to. */
2675 fntype
= TREE_TYPE (fntype
);
2677 /* Convert the parameters to the types declared in the
2678 function prototype, or apply default promotions. */
2680 coerced_params
= convert_arguments (TYPE_ARG_TYPES (fntype
),
2681 params
, fndecl
, LOOKUP_NORMAL
);
2682 if (coerced_params
== error_mark_node
)
2683 return error_mark_node
;
2685 /* Check for errors in format strings and inappropriately
2688 check_function_arguments (TYPE_ATTRIBUTES (fntype
), coerced_params
,
2689 TYPE_ARG_TYPES (fntype
));
2691 return build_cxx_call (function
, coerced_params
);
2694 /* Convert the actual parameter expressions in the list VALUES
2695 to the types in the list TYPELIST.
2696 If parmdecls is exhausted, or when an element has NULL as its type,
2697 perform the default conversions.
2699 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2701 This is also where warnings about wrong number of args are generated.
2703 Return a list of expressions for the parameters as converted.
2705 Both VALUES and the returned value are chains of TREE_LIST nodes
2706 with the elements of the list in the TREE_VALUE slots of those nodes.
2708 In C++, unspecified trailing parameters can be filled in with their
2709 default arguments, if such were specified. Do so here. */
2712 convert_arguments (tree typelist
, tree values
, tree fndecl
, int flags
)
2714 tree typetail
, valtail
;
2715 tree result
= NULL_TREE
;
2716 const char *called_thing
= 0;
2719 /* Argument passing is always copy-initialization. */
2720 flags
|= LOOKUP_ONLYCONVERTING
;
2724 if (TREE_CODE (TREE_TYPE (fndecl
)) == METHOD_TYPE
)
2726 if (DECL_NAME (fndecl
) == NULL_TREE
2727 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl
)))
2728 called_thing
= "constructor";
2730 called_thing
= "member function";
2733 called_thing
= "function";
2736 for (valtail
= values
, typetail
= typelist
;
2738 valtail
= TREE_CHAIN (valtail
), i
++)
2740 tree type
= typetail
? TREE_VALUE (typetail
) : 0;
2741 tree val
= TREE_VALUE (valtail
);
2743 if (val
== error_mark_node
|| type
== error_mark_node
)
2744 return error_mark_node
;
2746 if (type
== void_type_node
)
2750 error ("too many arguments to %s %q+#D", called_thing
, fndecl
);
2751 error ("at this point in file");
2754 error ("too many arguments to function");
2755 /* In case anybody wants to know if this argument
2758 TREE_TYPE (tree_last (result
)) = error_mark_node
;
2762 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2763 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2764 if (TREE_CODE (val
) == NOP_EXPR
2765 && TREE_TYPE (val
) == TREE_TYPE (TREE_OPERAND (val
, 0))
2766 && (type
== 0 || TREE_CODE (type
) != REFERENCE_TYPE
))
2767 val
= TREE_OPERAND (val
, 0);
2769 if (type
== 0 || TREE_CODE (type
) != REFERENCE_TYPE
)
2771 if (TREE_CODE (TREE_TYPE (val
)) == ARRAY_TYPE
2772 || TREE_CODE (TREE_TYPE (val
)) == FUNCTION_TYPE
2773 || TREE_CODE (TREE_TYPE (val
)) == METHOD_TYPE
)
2774 val
= decay_conversion (val
);
2777 if (val
== error_mark_node
)
2778 return error_mark_node
;
2782 /* Formal parm type is specified by a function prototype. */
2785 if (!COMPLETE_TYPE_P (complete_type (type
)))
2788 error ("parameter %P of %qD has incomplete type %qT",
2791 error ("parameter %P has incomplete type %qT", i
, type
);
2792 parmval
= error_mark_node
;
2796 parmval
= convert_for_initialization
2797 (NULL_TREE
, type
, val
, flags
,
2798 "argument passing", fndecl
, i
);
2799 parmval
= convert_for_arg_passing (type
, parmval
);
2802 if (parmval
== error_mark_node
)
2803 return error_mark_node
;
2805 result
= tree_cons (NULL_TREE
, parmval
, result
);
2809 if (fndecl
&& DECL_BUILT_IN (fndecl
)
2810 && DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_CONSTANT_P
)
2811 /* Don't do ellipsis conversion for __built_in_constant_p
2812 as this will result in spurious warnings for non-POD
2814 val
= require_complete_type (val
);
2816 val
= convert_arg_to_ellipsis (val
);
2818 result
= tree_cons (NULL_TREE
, val
, result
);
2822 typetail
= TREE_CHAIN (typetail
);
2825 if (typetail
!= 0 && typetail
!= void_list_node
)
2827 /* See if there are default arguments that can be used. */
2828 if (TREE_PURPOSE (typetail
)
2829 && TREE_CODE (TREE_PURPOSE (typetail
)) != DEFAULT_ARG
)
2831 for (; typetail
!= void_list_node
; ++i
)
2834 = convert_default_arg (TREE_VALUE (typetail
),
2835 TREE_PURPOSE (typetail
),
2838 if (parmval
== error_mark_node
)
2839 return error_mark_node
;
2841 result
= tree_cons (0, parmval
, result
);
2842 typetail
= TREE_CHAIN (typetail
);
2843 /* ends with `...'. */
2844 if (typetail
== NULL_TREE
)
2852 error ("too few arguments to %s %q+#D", called_thing
, fndecl
);
2853 error ("at this point in file");
2856 error ("too few arguments to function");
2857 return error_mark_node
;
2861 return nreverse (result
);
2864 /* Build a binary-operation expression, after performing default
2865 conversions on the operands. CODE is the kind of expression to build. */
2868 build_x_binary_op (enum tree_code code
, tree arg1
, tree arg2
,
2878 if (processing_template_decl
)
2880 if (type_dependent_expression_p (arg1
)
2881 || type_dependent_expression_p (arg2
))
2882 return build_min_nt (code
, arg1
, arg2
);
2883 arg1
= build_non_dependent_expr (arg1
);
2884 arg2
= build_non_dependent_expr (arg2
);
2887 if (code
== DOTSTAR_EXPR
)
2888 expr
= build_m_component_ref (arg1
, arg2
);
2890 expr
= build_new_op (code
, LOOKUP_NORMAL
, arg1
, arg2
, NULL_TREE
,
2893 if (processing_template_decl
&& expr
!= error_mark_node
)
2894 return build_min_non_dep (code
, expr
, orig_arg1
, orig_arg2
);
2899 /* Build a binary-operation expression without default conversions.
2900 CODE is the kind of expression to build.
2901 This function differs from `build' in several ways:
2902 the data type of the result is computed and recorded in it,
2903 warnings are generated if arg data types are invalid,
2904 special handling for addition and subtraction of pointers is known,
2905 and some optimization is done (operations on narrow ints
2906 are done in the narrower type when that gives the same result).
2907 Constant folding is also done before the result is returned.
2909 Note that the operands will never have enumeral types
2910 because either they have just had the default conversions performed
2911 or they have both just been converted to some other type in which
2912 the arithmetic is to be done.
2914 C++: must do special pointer arithmetic when implementing
2915 multiple inheritance, and deal with pointer to member functions. */
2918 build_binary_op (enum tree_code code
, tree orig_op0
, tree orig_op1
,
2919 int convert_p ATTRIBUTE_UNUSED
)
2922 enum tree_code code0
, code1
;
2924 const char *invalid_op_diag
;
2926 /* Expression code to give to the expression when it is built.
2927 Normally this is CODE, which is what the caller asked for,
2928 but in some special cases we change it. */
2929 enum tree_code resultcode
= code
;
2931 /* Data type in which the computation is to be performed.
2932 In the simplest cases this is the common type of the arguments. */
2933 tree result_type
= NULL
;
2935 /* Nonzero means operands have already been type-converted
2936 in whatever way is necessary.
2937 Zero means they need to be converted to RESULT_TYPE. */
2940 /* Nonzero means create the expression with this type, rather than
2942 tree build_type
= 0;
2944 /* Nonzero means after finally constructing the expression
2945 convert it to this type. */
2946 tree final_type
= 0;
2950 /* Nonzero if this is an operation like MIN or MAX which can
2951 safely be computed in short if both args are promoted shorts.
2952 Also implies COMMON.
2953 -1 indicates a bitwise operation; this makes a difference
2954 in the exact conditions for when it is safe to do the operation
2955 in a narrower mode. */
2958 /* Nonzero if this is a comparison operation;
2959 if both args are promoted shorts, compare the original shorts.
2960 Also implies COMMON. */
2961 int short_compare
= 0;
2963 /* Nonzero if this is a right-shift operation, which can be computed on the
2964 original short and then promoted if the operand is a promoted short. */
2965 int short_shift
= 0;
2967 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2970 /* True if both operands have arithmetic type. */
2971 bool arithmetic_types_p
;
2973 /* Apply default conversions. */
2977 if (code
== TRUTH_AND_EXPR
|| code
== TRUTH_ANDIF_EXPR
2978 || code
== TRUTH_OR_EXPR
|| code
== TRUTH_ORIF_EXPR
2979 || code
== TRUTH_XOR_EXPR
)
2981 if (!really_overloaded_fn (op0
))
2982 op0
= decay_conversion (op0
);
2983 if (!really_overloaded_fn (op1
))
2984 op1
= decay_conversion (op1
);
2988 if (!really_overloaded_fn (op0
))
2989 op0
= default_conversion (op0
);
2990 if (!really_overloaded_fn (op1
))
2991 op1
= default_conversion (op1
);
2994 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2995 STRIP_TYPE_NOPS (op0
);
2996 STRIP_TYPE_NOPS (op1
);
2998 /* DTRT if one side is an overloaded function, but complain about it. */
2999 if (type_unknown_p (op0
))
3001 tree t
= instantiate_type (TREE_TYPE (op1
), op0
, tf_none
);
3002 if (t
!= error_mark_node
)
3004 pedwarn ("assuming cast to type %qT from overloaded function",
3009 if (type_unknown_p (op1
))
3011 tree t
= instantiate_type (TREE_TYPE (op0
), op1
, tf_none
);
3012 if (t
!= error_mark_node
)
3014 pedwarn ("assuming cast to type %qT from overloaded function",
3020 type0
= TREE_TYPE (op0
);
3021 type1
= TREE_TYPE (op1
);
3023 /* The expression codes of the data types of the arguments tell us
3024 whether the arguments are integers, floating, pointers, etc. */
3025 code0
= TREE_CODE (type0
);
3026 code1
= TREE_CODE (type1
);
3028 /* If an error was already reported for one of the arguments,
3029 avoid reporting another error. */
3031 if (code0
== ERROR_MARK
|| code1
== ERROR_MARK
)
3032 return error_mark_node
;
3034 if ((invalid_op_diag
3035 = targetm
.invalid_binary_op (code
, type0
, type1
)))
3037 error (invalid_op_diag
);
3038 return error_mark_node
;
3044 /* Handle the pointer + int case. */
3045 if (code0
== POINTER_TYPE
&& code1
== INTEGER_TYPE
)
3046 return cp_pointer_int_sum (PLUS_EXPR
, op0
, op1
);
3047 else if (code1
== POINTER_TYPE
&& code0
== INTEGER_TYPE
)
3048 return cp_pointer_int_sum (PLUS_EXPR
, op1
, op0
);
3054 /* Subtraction of two similar pointers.
3055 We must subtract them as integers, then divide by object size. */
3056 if (code0
== POINTER_TYPE
&& code1
== POINTER_TYPE
3057 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0
),
3059 return pointer_diff (op0
, op1
, common_type (type0
, type1
));
3060 /* Handle pointer minus int. Just like pointer plus int. */
3061 else if (code0
== POINTER_TYPE
&& code1
== INTEGER_TYPE
)
3062 return cp_pointer_int_sum (MINUS_EXPR
, op0
, op1
);
3071 case TRUNC_DIV_EXPR
:
3073 case FLOOR_DIV_EXPR
:
3074 case ROUND_DIV_EXPR
:
3075 case EXACT_DIV_EXPR
:
3076 if ((code0
== INTEGER_TYPE
|| code0
== REAL_TYPE
3077 || code0
== COMPLEX_TYPE
|| code0
== VECTOR_TYPE
)
3078 && (code1
== INTEGER_TYPE
|| code1
== REAL_TYPE
3079 || code1
== COMPLEX_TYPE
|| code1
== VECTOR_TYPE
))
3081 if (TREE_CODE (op1
) == INTEGER_CST
&& integer_zerop (op1
))
3082 warning (OPT_Wdiv_by_zero
, "division by zero in %<%E / 0%>", op0
);
3083 else if (TREE_CODE (op1
) == REAL_CST
&& real_zerop (op1
))
3084 warning (OPT_Wdiv_by_zero
, "division by zero in %<%E / 0.%>", op0
);
3086 if (code0
== COMPLEX_TYPE
|| code0
== VECTOR_TYPE
)
3087 code0
= TREE_CODE (TREE_TYPE (TREE_TYPE (op0
)));
3088 if (code1
== COMPLEX_TYPE
|| code1
== VECTOR_TYPE
)
3089 code1
= TREE_CODE (TREE_TYPE (TREE_TYPE (op1
)));
3091 if (!(code0
== INTEGER_TYPE
&& code1
== INTEGER_TYPE
))
3092 resultcode
= RDIV_EXPR
;
3094 /* When dividing two signed integers, we have to promote to int.
3095 unless we divide by a constant != -1. Note that default
3096 conversion will have been performed on the operands at this
3097 point, so we have to dig out the original type to find out if
3099 shorten
= ((TREE_CODE (op0
) == NOP_EXPR
3100 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0
, 0))))
3101 || (TREE_CODE (op1
) == INTEGER_CST
3102 && ! integer_all_onesp (op1
)));
3111 if ((code0
== INTEGER_TYPE
&& code1
== INTEGER_TYPE
)
3112 || (code0
== VECTOR_TYPE
&& code1
== VECTOR_TYPE
))
3116 case TRUNC_MOD_EXPR
:
3117 case FLOOR_MOD_EXPR
:
3118 if (code1
== INTEGER_TYPE
&& integer_zerop (op1
))
3119 warning (OPT_Wdiv_by_zero
, "division by zero in %<%E %% 0%>", op0
);
3120 else if (code1
== REAL_TYPE
&& real_zerop (op1
))
3121 warning (OPT_Wdiv_by_zero
, "division by zero in %<%E %% 0.%>", op0
);
3123 if (code0
== INTEGER_TYPE
&& code1
== INTEGER_TYPE
)
3125 /* Although it would be tempting to shorten always here, that loses
3126 on some targets, since the modulo instruction is undefined if the
3127 quotient can't be represented in the computation mode. We shorten
3128 only if unsigned or if dividing by something we know != -1. */
3129 shorten
= ((TREE_CODE (op0
) == NOP_EXPR
3130 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0
, 0))))
3131 || (TREE_CODE (op1
) == INTEGER_CST
3132 && ! integer_all_onesp (op1
)));
3137 case TRUTH_ANDIF_EXPR
:
3138 case TRUTH_ORIF_EXPR
:
3139 case TRUTH_AND_EXPR
:
3141 result_type
= boolean_type_node
;
3144 /* Shift operations: result has same type as first operand;
3145 always convert second operand to int.
3146 Also set SHORT_SHIFT if shifting rightward. */
3149 if (code0
== INTEGER_TYPE
&& code1
== INTEGER_TYPE
)
3151 result_type
= type0
;
3152 if (TREE_CODE (op1
) == INTEGER_CST
)
3154 if (tree_int_cst_lt (op1
, integer_zero_node
))
3155 warning (0, "right shift count is negative");
3158 if (! integer_zerop (op1
))
3160 if (compare_tree_int (op1
, TYPE_PRECISION (type0
)) >= 0)
3161 warning (0, "right shift count >= width of type");
3164 /* Convert the shift-count to an integer, regardless of
3165 size of value being shifted. */
3166 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1
)) != integer_type_node
)
3167 op1
= cp_convert (integer_type_node
, op1
);
3168 /* Avoid converting op1 to result_type later. */
3174 if (code0
== INTEGER_TYPE
&& code1
== INTEGER_TYPE
)
3176 result_type
= type0
;
3177 if (TREE_CODE (op1
) == INTEGER_CST
)
3179 if (tree_int_cst_lt (op1
, integer_zero_node
))
3180 warning (0, "left shift count is negative");
3181 else if (compare_tree_int (op1
, TYPE_PRECISION (type0
)) >= 0)
3182 warning (0, "left shift count >= width of type");
3184 /* Convert the shift-count to an integer, regardless of
3185 size of value being shifted. */
3186 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1
)) != integer_type_node
)
3187 op1
= cp_convert (integer_type_node
, op1
);
3188 /* Avoid converting op1 to result_type later. */
3195 if (code0
== INTEGER_TYPE
&& code1
== INTEGER_TYPE
)
3197 result_type
= type0
;
3198 if (TREE_CODE (op1
) == INTEGER_CST
)
3200 if (tree_int_cst_lt (op1
, integer_zero_node
))
3201 warning (0, "%s rotate count is negative",
3202 (code
== LROTATE_EXPR
) ? "left" : "right");
3203 else if (compare_tree_int (op1
, TYPE_PRECISION (type0
)) >= 0)
3204 warning (0, "%s rotate count >= width of type",
3205 (code
== LROTATE_EXPR
) ? "left" : "right");
3207 /* Convert the shift-count to an integer, regardless of
3208 size of value being shifted. */
3209 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1
)) != integer_type_node
)
3210 op1
= cp_convert (integer_type_node
, op1
);
3216 if (code0
== REAL_TYPE
|| code1
== REAL_TYPE
)
3217 warning (OPT_Wfloat_equal
,
3218 "comparing floating point with == or != is unsafe");
3219 if ((TREE_CODE (orig_op0
) == STRING_CST
&& !integer_zerop (op1
))
3220 || (TREE_CODE (orig_op1
) == STRING_CST
&& !integer_zerop (op0
)))
3221 warning (OPT_Wstring_literal_comparison
,
3222 "comparison with string literal");
3224 build_type
= boolean_type_node
;
3225 if ((code0
== INTEGER_TYPE
|| code0
== REAL_TYPE
3226 || code0
== COMPLEX_TYPE
)
3227 && (code1
== INTEGER_TYPE
|| code1
== REAL_TYPE
3228 || code1
== COMPLEX_TYPE
))
3230 else if ((code0
== POINTER_TYPE
&& code1
== POINTER_TYPE
)
3231 || (TYPE_PTRMEM_P (type0
) && TYPE_PTRMEM_P (type1
)))
3232 result_type
= composite_pointer_type (type0
, type1
, op0
, op1
,
3234 else if ((code0
== POINTER_TYPE
|| TYPE_PTRMEM_P (type0
))
3235 && null_ptr_cst_p (op1
))
3236 result_type
= type0
;
3237 else if ((code1
== POINTER_TYPE
|| TYPE_PTRMEM_P (type1
))
3238 && null_ptr_cst_p (op0
))
3239 result_type
= type1
;
3240 else if (code0
== POINTER_TYPE
&& code1
== INTEGER_TYPE
)
3242 result_type
= type0
;
3243 error ("ISO C++ forbids comparison between pointer and integer");
3245 else if (code0
== INTEGER_TYPE
&& code1
== POINTER_TYPE
)
3247 result_type
= type1
;
3248 error ("ISO C++ forbids comparison between pointer and integer");
3250 else if (TYPE_PTRMEMFUNC_P (type0
) && null_ptr_cst_p (op1
))
3252 op0
= build_ptrmemfunc_access_expr (op0
, pfn_identifier
);
3253 op1
= cp_convert (TREE_TYPE (op0
), integer_zero_node
);
3254 result_type
= TREE_TYPE (op0
);
3256 else if (TYPE_PTRMEMFUNC_P (type1
) && null_ptr_cst_p (op0
))
3257 return cp_build_binary_op (code
, op1
, op0
);
3258 else if (TYPE_PTRMEMFUNC_P (type0
) && TYPE_PTRMEMFUNC_P (type1
)
3259 && same_type_p (type0
, type1
))
3261 /* E will be the final comparison. */
3263 /* E1 and E2 are for scratch. */
3271 if (TREE_SIDE_EFFECTS (op0
))
3272 op0
= save_expr (op0
);
3273 if (TREE_SIDE_EFFECTS (op1
))
3274 op1
= save_expr (op1
);
3279 && (!op0.pfn || op0.delta == op1.delta))
3281 The reason for the `!op0.pfn' bit is that a NULL
3282 pointer-to-member is any member with a zero PFN; the
3283 DELTA field is unspecified. */
3284 pfn0
= pfn_from_ptrmemfunc (op0
);
3285 pfn1
= pfn_from_ptrmemfunc (op1
);
3286 delta0
= build_ptrmemfunc_access_expr (op0
,
3288 delta1
= build_ptrmemfunc_access_expr (op1
,
3290 e1
= cp_build_binary_op (EQ_EXPR
, delta0
, delta1
);
3291 e2
= cp_build_binary_op (EQ_EXPR
,
3293 cp_convert (TREE_TYPE (pfn0
),
3294 integer_zero_node
));
3295 e1
= cp_build_binary_op (TRUTH_ORIF_EXPR
, e1
, e2
);
3296 e2
= build2 (EQ_EXPR
, boolean_type_node
, pfn0
, pfn1
);
3297 e
= cp_build_binary_op (TRUTH_ANDIF_EXPR
, e2
, e1
);
3298 if (code
== EQ_EXPR
)
3300 return cp_build_binary_op (EQ_EXPR
, e
, integer_zero_node
);
3304 gcc_assert (!TYPE_PTRMEMFUNC_P (type0
)
3305 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0
),
3307 gcc_assert (!TYPE_PTRMEMFUNC_P (type1
)
3308 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1
),
3316 if ((code0
== INTEGER_TYPE
|| code0
== REAL_TYPE
)
3317 && (code1
== INTEGER_TYPE
|| code1
== REAL_TYPE
))
3319 else if (code0
== POINTER_TYPE
&& code1
== POINTER_TYPE
)
3320 result_type
= composite_pointer_type (type0
, type1
, op0
, op1
,
3328 if (TREE_CODE (orig_op0
) == STRING_CST
3329 || TREE_CODE (orig_op1
) == STRING_CST
)
3330 warning (OPT_Wstring_literal_comparison
,
3331 "comparison with string literal");
3333 build_type
= boolean_type_node
;
3334 if ((code0
== INTEGER_TYPE
|| code0
== REAL_TYPE
)
3335 && (code1
== INTEGER_TYPE
|| code1
== REAL_TYPE
))
3337 else if (code0
== POINTER_TYPE
&& code1
== POINTER_TYPE
)
3338 result_type
= composite_pointer_type (type0
, type1
, op0
, op1
,
3340 else if (code0
== POINTER_TYPE
&& TREE_CODE (op1
) == INTEGER_CST
3341 && integer_zerop (op1
))
3342 result_type
= type0
;
3343 else if (code1
== POINTER_TYPE
&& TREE_CODE (op0
) == INTEGER_CST
3344 && integer_zerop (op0
))
3345 result_type
= type1
;
3346 else if (code0
== POINTER_TYPE
&& code1
== INTEGER_TYPE
)
3348 result_type
= type0
;
3349 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3351 else if (code0
== INTEGER_TYPE
&& code1
== POINTER_TYPE
)
3353 result_type
= type1
;
3354 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3358 case UNORDERED_EXPR
:
3365 build_type
= integer_type_node
;
3366 if (code0
!= REAL_TYPE
|| code1
!= REAL_TYPE
)
3368 error ("unordered comparison on non-floating point argument");
3369 return error_mark_node
;
3378 if (((code0
== INTEGER_TYPE
|| code0
== REAL_TYPE
|| code0
== COMPLEX_TYPE
)
3379 && (code1
== INTEGER_TYPE
|| code1
== REAL_TYPE
3380 || code1
== COMPLEX_TYPE
)))
3381 arithmetic_types_p
= 1;
3384 arithmetic_types_p
= 0;
3385 /* Vector arithmetic is only allowed when both sides are vectors. */
3386 if (code0
== VECTOR_TYPE
&& code1
== VECTOR_TYPE
)
3388 if (!tree_int_cst_equal (TYPE_SIZE (type0
), TYPE_SIZE (type1
))
3389 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0
),
3392 binary_op_error (code
);
3393 return error_mark_node
;
3395 arithmetic_types_p
= 1;
3398 /* Determine the RESULT_TYPE, if it is not already known. */
3400 && arithmetic_types_p
3401 && (shorten
|| common
|| short_compare
))
3402 result_type
= common_type (type0
, type1
);
3406 error ("invalid operands of types %qT and %qT to binary %qO",
3407 TREE_TYPE (orig_op0
), TREE_TYPE (orig_op1
), code
);
3408 return error_mark_node
;
3411 /* If we're in a template, the only thing we need to know is the
3413 if (processing_template_decl
)
3414 return build2 (resultcode
,
3415 build_type
? build_type
: result_type
,
3418 if (arithmetic_types_p
)
3420 int none_complex
= (code0
!= COMPLEX_TYPE
&& code1
!= COMPLEX_TYPE
);
3422 /* For certain operations (which identify themselves by shorten != 0)
3423 if both args were extended from the same smaller type,
3424 do the arithmetic in that type and then extend.
3426 shorten !=0 and !=1 indicates a bitwise operation.
3427 For them, this optimization is safe only if
3428 both args are zero-extended or both are sign-extended.
3429 Otherwise, we might change the result.
3430 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3431 but calculated in (unsigned short) it would be (unsigned short)-1. */
3433 if (shorten
&& none_complex
)
3435 int unsigned0
, unsigned1
;
3436 tree arg0
= get_narrower (op0
, &unsigned0
);
3437 tree arg1
= get_narrower (op1
, &unsigned1
);
3438 /* UNS is 1 if the operation to be done is an unsigned one. */
3439 int uns
= TYPE_UNSIGNED (result_type
);
3442 final_type
= result_type
;
3444 /* Handle the case that OP0 does not *contain* a conversion
3445 but it *requires* conversion to FINAL_TYPE. */
3447 if (op0
== arg0
&& TREE_TYPE (op0
) != final_type
)
3448 unsigned0
= TYPE_UNSIGNED (TREE_TYPE (op0
));
3449 if (op1
== arg1
&& TREE_TYPE (op1
) != final_type
)
3450 unsigned1
= TYPE_UNSIGNED (TREE_TYPE (op1
));
3452 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3454 /* For bitwise operations, signedness of nominal type
3455 does not matter. Consider only how operands were extended. */
3459 /* Note that in all three cases below we refrain from optimizing
3460 an unsigned operation on sign-extended args.
3461 That would not be valid. */
3463 /* Both args variable: if both extended in same way
3464 from same width, do it in that width.
3465 Do it unsigned if args were zero-extended. */
3466 if ((TYPE_PRECISION (TREE_TYPE (arg0
))
3467 < TYPE_PRECISION (result_type
))
3468 && (TYPE_PRECISION (TREE_TYPE (arg1
))
3469 == TYPE_PRECISION (TREE_TYPE (arg0
)))
3470 && unsigned0
== unsigned1
3471 && (unsigned0
|| !uns
))
3472 result_type
= c_common_signed_or_unsigned_type
3473 (unsigned0
, common_type (TREE_TYPE (arg0
), TREE_TYPE (arg1
)));
3474 else if (TREE_CODE (arg0
) == INTEGER_CST
3475 && (unsigned1
|| !uns
)
3476 && (TYPE_PRECISION (TREE_TYPE (arg1
))
3477 < TYPE_PRECISION (result_type
))
3478 && (type
= c_common_signed_or_unsigned_type
3479 (unsigned1
, TREE_TYPE (arg1
)),
3480 int_fits_type_p (arg0
, type
)))
3482 else if (TREE_CODE (arg1
) == INTEGER_CST
3483 && (unsigned0
|| !uns
)
3484 && (TYPE_PRECISION (TREE_TYPE (arg0
))
3485 < TYPE_PRECISION (result_type
))
3486 && (type
= c_common_signed_or_unsigned_type
3487 (unsigned0
, TREE_TYPE (arg0
)),
3488 int_fits_type_p (arg1
, type
)))
3492 /* Shifts can be shortened if shifting right. */
3497 tree arg0
= get_narrower (op0
, &unsigned_arg
);
3499 final_type
= result_type
;
3501 if (arg0
== op0
&& final_type
== TREE_TYPE (op0
))
3502 unsigned_arg
= TYPE_UNSIGNED (TREE_TYPE (op0
));
3504 if (TYPE_PRECISION (TREE_TYPE (arg0
)) < TYPE_PRECISION (result_type
)
3505 /* We can shorten only if the shift count is less than the
3506 number of bits in the smaller type size. */
3507 && compare_tree_int (op1
, TYPE_PRECISION (TREE_TYPE (arg0
))) < 0
3508 /* If arg is sign-extended and then unsigned-shifted,
3509 we can simulate this with a signed shift in arg's type
3510 only if the extended result is at least twice as wide
3511 as the arg. Otherwise, the shift could use up all the
3512 ones made by sign-extension and bring in zeros.
3513 We can't optimize that case at all, but in most machines
3514 it never happens because available widths are 2**N. */
3515 && (!TYPE_UNSIGNED (final_type
)
3517 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0
)))
3518 <= TYPE_PRECISION (result_type
))))
3520 /* Do an unsigned shift if the operand was zero-extended. */
3522 = c_common_signed_or_unsigned_type (unsigned_arg
,
3524 /* Convert value-to-be-shifted to that type. */
3525 if (TREE_TYPE (op0
) != result_type
)
3526 op0
= cp_convert (result_type
, op0
);
3531 /* Comparison operations are shortened too but differently.
3532 They identify themselves by setting short_compare = 1. */
3536 /* Don't write &op0, etc., because that would prevent op0
3537 from being kept in a register.
3538 Instead, make copies of the our local variables and
3539 pass the copies by reference, then copy them back afterward. */
3540 tree xop0
= op0
, xop1
= op1
, xresult_type
= result_type
;
3541 enum tree_code xresultcode
= resultcode
;
3543 = shorten_compare (&xop0
, &xop1
, &xresult_type
, &xresultcode
);
3545 return cp_convert (boolean_type_node
, val
);
3546 op0
= xop0
, op1
= xop1
;
3548 resultcode
= xresultcode
;
3551 if ((short_compare
|| code
== MIN_EXPR
|| code
== MAX_EXPR
)
3552 && warn_sign_compare
3553 /* Do not warn until the template is instantiated; we cannot
3554 bound the ranges of the arguments until that point. */
3555 && !processing_template_decl
)
3557 int op0_signed
= !TYPE_UNSIGNED (TREE_TYPE (orig_op0
));
3558 int op1_signed
= !TYPE_UNSIGNED (TREE_TYPE (orig_op1
));
3560 int unsignedp0
, unsignedp1
;
3561 tree primop0
= get_narrower (op0
, &unsignedp0
);
3562 tree primop1
= get_narrower (op1
, &unsignedp1
);
3564 /* Check for comparison of different enum types. */
3565 if (TREE_CODE (TREE_TYPE (orig_op0
)) == ENUMERAL_TYPE
3566 && TREE_CODE (TREE_TYPE (orig_op1
)) == ENUMERAL_TYPE
3567 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0
))
3568 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1
)))
3570 warning (0, "comparison between types %q#T and %q#T",
3571 TREE_TYPE (orig_op0
), TREE_TYPE (orig_op1
));
3574 /* Give warnings for comparisons between signed and unsigned
3575 quantities that may fail. */
3576 /* Do the checking based on the original operand trees, so that
3577 casts will be considered, but default promotions won't be. */
3579 /* Do not warn if the comparison is being done in a signed type,
3580 since the signed type will only be chosen if it can represent
3581 all the values of the unsigned type. */
3582 if (!TYPE_UNSIGNED (result_type
))
3584 /* Do not warn if both operands are unsigned. */
3585 else if (op0_signed
== op1_signed
)
3587 /* Do not warn if the signed quantity is an unsuffixed
3588 integer literal (or some static constant expression
3589 involving such literals or a conditional expression
3590 involving such literals) and it is non-negative. */
3591 else if ((op0_signed
&& tree_expr_nonnegative_p (orig_op0
))
3592 || (op1_signed
&& tree_expr_nonnegative_p (orig_op1
)))
3594 /* Do not warn if the comparison is an equality operation,
3595 the unsigned quantity is an integral constant and it does
3596 not use the most significant bit of result_type. */
3597 else if ((resultcode
== EQ_EXPR
|| resultcode
== NE_EXPR
)
3598 && ((op0_signed
&& TREE_CODE (orig_op1
) == INTEGER_CST
3599 && int_fits_type_p (orig_op1
, c_common_signed_type
3601 || (op1_signed
&& TREE_CODE (orig_op0
) == INTEGER_CST
3602 && int_fits_type_p (orig_op0
, c_common_signed_type
3606 warning (0, "comparison between signed and unsigned integer expressions");
3608 /* Warn if two unsigned values are being compared in a size
3609 larger than their original size, and one (and only one) is the
3610 result of a `~' operator. This comparison will always fail.
3612 Also warn if one operand is a constant, and the constant does not
3613 have all bits set that are set in the ~ operand when it is
3616 if ((TREE_CODE (primop0
) == BIT_NOT_EXPR
)
3617 ^ (TREE_CODE (primop1
) == BIT_NOT_EXPR
))
3619 if (TREE_CODE (primop0
) == BIT_NOT_EXPR
)
3620 primop0
= get_narrower (TREE_OPERAND (op0
, 0), &unsignedp0
);
3621 if (TREE_CODE (primop1
) == BIT_NOT_EXPR
)
3622 primop1
= get_narrower (TREE_OPERAND (op1
, 0), &unsignedp1
);
3624 if (host_integerp (primop0
, 0) || host_integerp (primop1
, 0))
3627 HOST_WIDE_INT constant
, mask
;
3631 if (host_integerp (primop0
, 0))
3634 unsignedp
= unsignedp1
;
3635 constant
= tree_low_cst (primop0
, 0);
3640 unsignedp
= unsignedp0
;
3641 constant
= tree_low_cst (primop1
, 0);
3644 bits
= TYPE_PRECISION (TREE_TYPE (primop
));
3645 if (bits
< TYPE_PRECISION (result_type
)
3646 && bits
< HOST_BITS_PER_LONG
&& unsignedp
)
3648 mask
= (~ (HOST_WIDE_INT
) 0) << bits
;
3649 if ((mask
& constant
) != mask
)
3650 warning (0, "comparison of promoted ~unsigned with constant");
3653 else if (unsignedp0
&& unsignedp1
3654 && (TYPE_PRECISION (TREE_TYPE (primop0
))
3655 < TYPE_PRECISION (result_type
))
3656 && (TYPE_PRECISION (TREE_TYPE (primop1
))
3657 < TYPE_PRECISION (result_type
)))
3658 warning (0, "comparison of promoted ~unsigned with unsigned");
3663 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3664 Then the expression will be built.
3665 It will be given type FINAL_TYPE if that is nonzero;
3666 otherwise, it will be given type RESULT_TYPE. */
3668 /* Issue warnings about peculiar, but valid, uses of NULL. */
3669 if (/* It's reasonable to use pointer values as operands of &&
3670 and ||, so NULL is no exception. */
3671 !(code
== TRUTH_ANDIF_EXPR
|| code
== TRUTH_ORIF_EXPR
)
3672 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3673 (orig_op0
== null_node
3674 && TREE_CODE (TREE_TYPE (op1
)) != POINTER_TYPE
)
3675 /* Or vice versa. */
3676 || (orig_op1
== null_node
3677 && TREE_CODE (TREE_TYPE (op0
)) != POINTER_TYPE
)
3678 /* Or, both are NULL and the operation was not a comparison. */
3679 || (orig_op0
== null_node
&& orig_op1
== null_node
3680 && code
!= EQ_EXPR
&& code
!= NE_EXPR
)))
3681 /* Some sort of arithmetic operation involving NULL was
3682 performed. Note that pointer-difference and pointer-addition
3683 have already been handled above, and so we don't end up here in
3685 warning (0, "NULL used in arithmetic");
3689 if (TREE_TYPE (op0
) != result_type
)
3690 op0
= cp_convert (result_type
, op0
);
3691 if (TREE_TYPE (op1
) != result_type
)
3692 op1
= cp_convert (result_type
, op1
);
3694 if (op0
== error_mark_node
|| op1
== error_mark_node
)
3695 return error_mark_node
;
3698 if (build_type
== NULL_TREE
)
3699 build_type
= result_type
;
3701 result
= build2 (resultcode
, build_type
, op0
, op1
);
3702 result
= fold_if_not_in_template (result
);
3703 if (final_type
!= 0)
3704 result
= cp_convert (final_type
, result
);
3708 /* Return a tree for the sum or difference (RESULTCODE says which)
3709 of pointer PTROP and integer INTOP. */
3712 cp_pointer_int_sum (enum tree_code resultcode
, tree ptrop
, tree intop
)
3714 tree res_type
= TREE_TYPE (ptrop
);
3716 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3717 in certain circumstance (when it's valid to do so). So we need
3718 to make sure it's complete. We don't need to check here, if we
3719 can actually complete it at all, as those checks will be done in
3720 pointer_int_sum() anyway. */
3721 complete_type (TREE_TYPE (res_type
));
3723 return pointer_int_sum (resultcode
, ptrop
,
3724 fold_if_not_in_template (intop
));
3727 /* Return a tree for the difference of pointers OP0 and OP1.
3728 The resulting tree has type int. */
3731 pointer_diff (tree op0
, tree op1
, tree ptrtype
)
3734 tree restype
= ptrdiff_type_node
;
3735 tree target_type
= TREE_TYPE (ptrtype
);
3737 if (!complete_type_or_else (target_type
, NULL_TREE
))
3738 return error_mark_node
;
3740 if (pedantic
|| warn_pointer_arith
)
3742 if (TREE_CODE (target_type
) == VOID_TYPE
)
3743 pedwarn ("ISO C++ forbids using pointer of type %<void *%> in subtraction");
3744 if (TREE_CODE (target_type
) == FUNCTION_TYPE
)
3745 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3746 if (TREE_CODE (target_type
) == METHOD_TYPE
)
3747 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3750 /* First do the subtraction as integers;
3751 then drop through to build the divide operator. */
3753 op0
= cp_build_binary_op (MINUS_EXPR
,
3754 cp_convert (restype
, op0
),
3755 cp_convert (restype
, op1
));
3757 /* This generates an error if op1 is a pointer to an incomplete type. */
3758 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1
))))
3759 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3761 op1
= (TYPE_PTROB_P (ptrtype
)
3762 ? size_in_bytes (target_type
)
3763 : integer_one_node
);
3765 /* Do the division. */
3767 result
= build2 (EXACT_DIV_EXPR
, restype
, op0
, cp_convert (restype
, op1
));
3768 return fold_if_not_in_template (result
);
3771 /* Construct and perhaps optimize a tree representation
3772 for a unary operation. CODE, a tree_code, specifies the operation
3773 and XARG is the operand. */
3776 build_x_unary_op (enum tree_code code
, tree xarg
)
3778 tree orig_expr
= xarg
;
3782 if (processing_template_decl
)
3784 if (type_dependent_expression_p (xarg
))
3785 return build_min_nt (code
, xarg
, NULL_TREE
);
3787 xarg
= build_non_dependent_expr (xarg
);
3792 /* [expr.unary.op] says:
3794 The address of an object of incomplete type can be taken.
3796 (And is just the ordinary address operator, not an overloaded
3797 "operator &".) However, if the type is a template
3798 specialization, we must complete the type at this point so that
3799 an overloaded "operator &" will be available if required. */
3800 if (code
== ADDR_EXPR
3801 && TREE_CODE (xarg
) != TEMPLATE_ID_EXPR
3802 && ((CLASS_TYPE_P (TREE_TYPE (xarg
))
3803 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg
))))
3804 || (TREE_CODE (xarg
) == OFFSET_REF
)))
3805 /* Don't look for a function. */;
3807 exp
= build_new_op (code
, LOOKUP_NORMAL
, xarg
, NULL_TREE
, NULL_TREE
,
3808 /*overloaded_p=*/NULL
);
3809 if (!exp
&& code
== ADDR_EXPR
)
3811 /* A pointer to member-function can be formed only by saying
3813 if (!flag_ms_extensions
&& TREE_CODE (TREE_TYPE (xarg
)) == METHOD_TYPE
3814 && (TREE_CODE (xarg
) != OFFSET_REF
|| !PTRMEM_OK_P (xarg
)))
3816 if (TREE_CODE (xarg
) != OFFSET_REF
3817 || !TYPE_P (TREE_OPERAND (xarg
, 0)))
3819 error ("invalid use of %qE to form a pointer-to-member-function",
3821 if (TREE_CODE (xarg
) != OFFSET_REF
)
3822 inform (" a qualified-id is required");
3823 return error_mark_node
;
3827 error ("parentheses around %qE cannot be used to form a"
3828 " pointer-to-member-function",
3830 PTRMEM_OK_P (xarg
) = 1;
3834 if (TREE_CODE (xarg
) == OFFSET_REF
)
3836 ptrmem
= PTRMEM_OK_P (xarg
);
3838 if (!ptrmem
&& !flag_ms_extensions
3839 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg
, 1))) == METHOD_TYPE
)
3841 /* A single non-static member, make sure we don't allow a
3842 pointer-to-member. */
3843 xarg
= build2 (OFFSET_REF
, TREE_TYPE (xarg
),
3844 TREE_OPERAND (xarg
, 0),
3845 ovl_cons (TREE_OPERAND (xarg
, 1), NULL_TREE
));
3846 PTRMEM_OK_P (xarg
) = ptrmem
;
3849 else if (TREE_CODE (xarg
) == TARGET_EXPR
)
3850 warning (0, "taking address of temporary");
3851 exp
= build_unary_op (ADDR_EXPR
, xarg
, 0);
3854 if (processing_template_decl
&& exp
!= error_mark_node
)
3855 exp
= build_min_non_dep (code
, exp
, orig_expr
,
3856 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE
);
3857 if (TREE_CODE (exp
) == ADDR_EXPR
)
3858 PTRMEM_OK_P (exp
) = ptrmem
;
3862 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3863 constants, where a null value is represented by an INTEGER_CST of
3867 cp_truthvalue_conversion (tree expr
)
3869 tree type
= TREE_TYPE (expr
);
3870 if (TYPE_PTRMEM_P (type
))
3871 return build_binary_op (NE_EXPR
, expr
, integer_zero_node
, 1);
3873 return c_common_truthvalue_conversion (expr
);
3876 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3879 condition_conversion (tree expr
)
3882 if (processing_template_decl
)
3884 t
= perform_implicit_conversion (boolean_type_node
, expr
);
3885 t
= fold_build_cleanup_point_expr (boolean_type_node
, t
);
3889 /* Return an ADDR_EXPR giving the address of T. This function
3890 attempts no optimizations or simplifications; it is a low-level
3894 build_address (tree t
)
3898 if (error_operand_p (t
) || !cxx_mark_addressable (t
))
3899 return error_mark_node
;
3901 addr
= build1 (ADDR_EXPR
, build_pointer_type (TREE_TYPE (t
)), t
);
3906 /* Return a NOP_EXPR converting EXPR to TYPE. */
3909 build_nop (tree type
, tree expr
)
3911 if (type
== error_mark_node
|| error_operand_p (expr
))
3913 return build1 (NOP_EXPR
, type
, expr
);
3916 /* C++: Must handle pointers to members.
3918 Perhaps type instantiation should be extended to handle conversion
3919 from aggregates to types we don't yet know we want? (Or are those
3920 cases typically errors which should be reported?)
3922 NOCONVERT nonzero suppresses the default promotions
3923 (such as from short to int). */
3926 build_unary_op (enum tree_code code
, tree xarg
, int noconvert
)
3928 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3931 const char *errstring
= NULL
;
3933 const char *invalid_op_diag
;
3935 if (arg
== error_mark_node
)
3936 return error_mark_node
;
3938 if ((invalid_op_diag
3939 = targetm
.invalid_unary_op ((code
== UNARY_PLUS_EXPR
3944 error (invalid_op_diag
);
3945 return error_mark_node
;
3950 case UNARY_PLUS_EXPR
:
3953 int flags
= WANT_ARITH
| WANT_ENUM
;
3954 /* Unary plus (but not unary minus) is allowed on pointers. */
3955 if (code
== UNARY_PLUS_EXPR
)
3956 flags
|= WANT_POINTER
;
3957 arg
= build_expr_type_conversion (flags
, arg
, true);
3959 errstring
= (code
== NEGATE_EXPR
3960 ? "wrong type argument to unary minus"
3961 : "wrong type argument to unary plus");
3964 if (!noconvert
&& CP_INTEGRAL_TYPE_P (TREE_TYPE (arg
)))
3965 arg
= perform_integral_promotions (arg
);
3967 /* Make sure the result is not an lvalue: a unary plus or minus
3968 expression is always a rvalue. */
3975 if (TREE_CODE (TREE_TYPE (arg
)) == COMPLEX_TYPE
)
3979 arg
= default_conversion (arg
);
3981 else if (!(arg
= build_expr_type_conversion (WANT_INT
| WANT_ENUM
,
3983 errstring
= "wrong type argument to bit-complement";
3984 else if (!noconvert
)
3985 arg
= perform_integral_promotions (arg
);
3989 if (!(arg
= build_expr_type_conversion (WANT_ARITH
| WANT_ENUM
, arg
, true)))
3990 errstring
= "wrong type argument to abs";
3991 else if (!noconvert
)
3992 arg
= default_conversion (arg
);
3996 /* Conjugating a real value is a no-op, but allow it anyway. */
3997 if (!(arg
= build_expr_type_conversion (WANT_ARITH
| WANT_ENUM
, arg
, true)))
3998 errstring
= "wrong type argument to conjugation";
3999 else if (!noconvert
)
4000 arg
= default_conversion (arg
);
4003 case TRUTH_NOT_EXPR
:
4004 arg
= perform_implicit_conversion (boolean_type_node
, arg
);
4005 val
= invert_truthvalue (arg
);
4006 if (arg
!= error_mark_node
)
4008 errstring
= "in argument to unary !";
4015 if (TREE_CODE (arg
) == COMPLEX_CST
)
4016 return TREE_REALPART (arg
);
4017 else if (TREE_CODE (TREE_TYPE (arg
)) == COMPLEX_TYPE
)
4019 arg
= build1 (REALPART_EXPR
, TREE_TYPE (TREE_TYPE (arg
)), arg
);
4020 return fold_if_not_in_template (arg
);
4026 if (TREE_CODE (arg
) == COMPLEX_CST
)
4027 return TREE_IMAGPART (arg
);
4028 else if (TREE_CODE (TREE_TYPE (arg
)) == COMPLEX_TYPE
)
4030 arg
= build1 (IMAGPART_EXPR
, TREE_TYPE (TREE_TYPE (arg
)), arg
);
4031 return fold_if_not_in_template (arg
);
4034 return cp_convert (TREE_TYPE (arg
), integer_zero_node
);
4036 case PREINCREMENT_EXPR
:
4037 case POSTINCREMENT_EXPR
:
4038 case PREDECREMENT_EXPR
:
4039 case POSTDECREMENT_EXPR
:
4040 /* Handle complex lvalues (when permitted)
4041 by reduction to simpler cases. */
4043 val
= unary_complex_lvalue (code
, arg
);
4047 /* Increment or decrement the real part of the value,
4048 and don't change the imaginary part. */
4049 if (TREE_CODE (TREE_TYPE (arg
)) == COMPLEX_TYPE
)
4053 arg
= stabilize_reference (arg
);
4054 real
= build_unary_op (REALPART_EXPR
, arg
, 1);
4055 imag
= build_unary_op (IMAGPART_EXPR
, arg
, 1);
4056 return build2 (COMPLEX_EXPR
, TREE_TYPE (arg
),
4057 build_unary_op (code
, real
, 1), imag
);
4060 /* Report invalid types. */
4062 if (!(arg
= build_expr_type_conversion (WANT_ARITH
| WANT_POINTER
,
4065 if (code
== PREINCREMENT_EXPR
)
4066 errstring
="no pre-increment operator for type";
4067 else if (code
== POSTINCREMENT_EXPR
)
4068 errstring
="no post-increment operator for type";
4069 else if (code
== PREDECREMENT_EXPR
)
4070 errstring
="no pre-decrement operator for type";
4072 errstring
="no post-decrement operator for type";
4076 /* Report something read-only. */
4078 if (CP_TYPE_CONST_P (TREE_TYPE (arg
))
4079 || TREE_READONLY (arg
))
4080 readonly_error (arg
, ((code
== PREINCREMENT_EXPR
4081 || code
== POSTINCREMENT_EXPR
)
4082 ? "increment" : "decrement"),
4087 tree result_type
= TREE_TYPE (arg
);
4089 arg
= get_unwidened (arg
, 0);
4090 argtype
= TREE_TYPE (arg
);
4092 /* ARM $5.2.5 last annotation says this should be forbidden. */
4093 if (TREE_CODE (argtype
) == ENUMERAL_TYPE
)
4094 pedwarn ("ISO C++ forbids %sing an enum",
4095 (code
== PREINCREMENT_EXPR
|| code
== POSTINCREMENT_EXPR
)
4096 ? "increment" : "decrement");
4098 /* Compute the increment. */
4100 if (TREE_CODE (argtype
) == POINTER_TYPE
)
4102 tree type
= complete_type (TREE_TYPE (argtype
));
4104 if (!COMPLETE_OR_VOID_TYPE_P (type
))
4105 error ("cannot %s a pointer to incomplete type %qT",
4106 ((code
== PREINCREMENT_EXPR
4107 || code
== POSTINCREMENT_EXPR
)
4108 ? "increment" : "decrement"), TREE_TYPE (argtype
));
4109 else if ((pedantic
|| warn_pointer_arith
)
4110 && !TYPE_PTROB_P (argtype
))
4111 pedwarn ("ISO C++ forbids %sing a pointer of type %qT",
4112 ((code
== PREINCREMENT_EXPR
4113 || code
== POSTINCREMENT_EXPR
)
4114 ? "increment" : "decrement"), argtype
);
4115 inc
= cxx_sizeof_nowarn (TREE_TYPE (argtype
));
4118 inc
= integer_one_node
;
4120 inc
= cp_convert (argtype
, inc
);
4122 /* Handle incrementing a cast-expression. */
4124 switch (TREE_CODE (arg
))
4129 case FIX_TRUNC_EXPR
:
4130 case FIX_FLOOR_EXPR
:
4131 case FIX_ROUND_EXPR
:
4134 tree incremented
, modify
, value
, compound
;
4135 if (! lvalue_p (arg
) && pedantic
)
4136 pedwarn ("cast to non-reference type used as lvalue");
4137 arg
= stabilize_reference (arg
);
4138 if (code
== PREINCREMENT_EXPR
|| code
== PREDECREMENT_EXPR
)
4141 value
= save_expr (arg
);
4142 incremented
= build2 (((code
== PREINCREMENT_EXPR
4143 || code
== POSTINCREMENT_EXPR
)
4144 ? PLUS_EXPR
: MINUS_EXPR
),
4145 argtype
, value
, inc
);
4147 modify
= build_modify_expr (arg
, NOP_EXPR
, incremented
);
4148 compound
= build2 (COMPOUND_EXPR
, TREE_TYPE (arg
),
4151 /* Eliminate warning about unused result of + or -. */
4152 TREE_NO_WARNING (compound
) = 1;
4160 /* Complain about anything else that is not a true lvalue. */
4161 if (!lvalue_or_else (arg
, ((code
== PREINCREMENT_EXPR
4162 || code
== POSTINCREMENT_EXPR
)
4163 ? lv_increment
: lv_decrement
)))
4164 return error_mark_node
;
4166 /* Forbid using -- on `bool'. */
4167 if (TREE_TYPE (arg
) == boolean_type_node
)
4169 if (code
== POSTDECREMENT_EXPR
|| code
== PREDECREMENT_EXPR
)
4171 error ("invalid use of %<--%> on bool variable %qD", arg
);
4172 return error_mark_node
;
4174 val
= boolean_increment (code
, arg
);
4177 val
= build2 (code
, TREE_TYPE (arg
), arg
, inc
);
4179 TREE_SIDE_EFFECTS (val
) = 1;
4180 return cp_convert (result_type
, val
);
4184 /* Note that this operation never does default_conversion
4185 regardless of NOCONVERT. */
4187 argtype
= lvalue_type (arg
);
4189 if (TREE_CODE (arg
) == OFFSET_REF
)
4192 if (TREE_CODE (argtype
) == REFERENCE_TYPE
)
4194 tree type
= build_pointer_type (TREE_TYPE (argtype
));
4195 arg
= build1 (CONVERT_EXPR
, type
, arg
);
4198 else if (pedantic
&& DECL_MAIN_P (arg
))
4200 pedwarn ("ISO C++ forbids taking address of function %<::main%>");
4202 /* Let &* cancel out to simplify resulting code. */
4203 if (TREE_CODE (arg
) == INDIRECT_REF
)
4205 /* We don't need to have `current_class_ptr' wrapped in a
4206 NON_LVALUE_EXPR node. */
4207 if (arg
== current_class_ref
)
4208 return current_class_ptr
;
4210 arg
= TREE_OPERAND (arg
, 0);
4211 if (TREE_CODE (TREE_TYPE (arg
)) == REFERENCE_TYPE
)
4213 tree type
= build_pointer_type (TREE_TYPE (TREE_TYPE (arg
)));
4214 arg
= build1 (CONVERT_EXPR
, type
, arg
);
4217 /* Don't let this be an lvalue. */
4222 /* Uninstantiated types are all functions. Taking the
4223 address of a function is a no-op, so just return the
4226 gcc_assert (TREE_CODE (arg
) != IDENTIFIER_NODE
4227 || !IDENTIFIER_OPNAME_P (arg
));
4229 if (TREE_CODE (arg
) == COMPONENT_REF
&& type_unknown_p (arg
)
4230 && !really_overloaded_fn (TREE_OPERAND (arg
, 1)))
4232 /* They're trying to take the address of a unique non-static
4233 member function. This is ill-formed (except in MS-land),
4234 but let's try to DTRT.
4235 Note: We only handle unique functions here because we don't
4236 want to complain if there's a static overload; non-unique
4237 cases will be handled by instantiate_type. But we need to
4238 handle this case here to allow casts on the resulting PMF.
4239 We could defer this in non-MS mode, but it's easier to give
4240 a useful error here. */
4242 /* Inside constant member functions, the `this' pointer
4243 contains an extra const qualifier. TYPE_MAIN_VARIANT
4244 is used here to remove this const from the diagnostics
4245 and the created OFFSET_REF. */
4246 tree base
= TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg
, 0)));
4247 tree fn
= get_first_fn (TREE_OPERAND (arg
, 1));
4250 if (! flag_ms_extensions
)
4252 tree name
= DECL_NAME (fn
);
4253 if (current_class_type
4254 && TREE_OPERAND (arg
, 0) == current_class_ref
)
4255 /* An expression like &memfn. */
4256 pedwarn ("ISO C++ forbids taking the address of an unqualified"
4257 " or parenthesized non-static member function to form"
4258 " a pointer to member function. Say %<&%T::%D%>",
4261 pedwarn ("ISO C++ forbids taking the address of a bound member"
4262 " function to form a pointer to member function."
4266 arg
= build_offset_ref (base
, fn
, /*address_p=*/true);
4270 if (type_unknown_p (arg
))
4271 return build1 (ADDR_EXPR
, unknown_type_node
, arg
);
4273 /* Handle complex lvalues (when permitted)
4274 by reduction to simpler cases. */
4275 val
= unary_complex_lvalue (code
, arg
);
4279 switch (TREE_CODE (arg
))
4284 case FIX_TRUNC_EXPR
:
4285 case FIX_FLOOR_EXPR
:
4286 case FIX_ROUND_EXPR
:
4288 if (! lvalue_p (arg
) && pedantic
)
4289 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4293 arg
= OVL_CURRENT (arg
);
4297 /* Turn a reference to a non-static data member into a
4298 pointer-to-member. */
4303 if (!PTRMEM_OK_P (arg
))
4304 return build_unary_op (code
, arg
, 0);
4306 t
= TREE_OPERAND (arg
, 1);
4307 if (TREE_CODE (TREE_TYPE (t
)) == REFERENCE_TYPE
)
4309 error ("cannot create pointer to reference member %qD", t
);
4310 return error_mark_node
;
4313 type
= build_ptrmem_type (context_for_name_lookup (t
),
4315 t
= make_ptrmem_cst (type
, TREE_OPERAND (arg
, 1));
4323 /* Anything not already handled and not a true memory reference
4325 if (TREE_CODE (argtype
) != FUNCTION_TYPE
4326 && TREE_CODE (argtype
) != METHOD_TYPE
4327 && TREE_CODE (arg
) != OFFSET_REF
4328 && !lvalue_or_else (arg
, lv_addressof
))
4329 return error_mark_node
;
4331 if (argtype
!= error_mark_node
)
4332 argtype
= build_pointer_type (argtype
);
4334 /* In a template, we are processing a non-dependent expression
4335 so we can just form an ADDR_EXPR with the correct type. */
4336 if (processing_template_decl
)
4338 val
= build_address (arg
);
4339 if (TREE_CODE (arg
) == OFFSET_REF
)
4340 PTRMEM_OK_P (val
) = PTRMEM_OK_P (arg
);
4344 if (TREE_CODE (arg
) != COMPONENT_REF
)
4346 val
= build_address (arg
);
4347 if (TREE_CODE (arg
) == OFFSET_REF
)
4348 PTRMEM_OK_P (val
) = PTRMEM_OK_P (arg
);
4350 else if (TREE_CODE (TREE_OPERAND (arg
, 1)) == BASELINK
)
4352 tree fn
= BASELINK_FUNCTIONS (TREE_OPERAND (arg
, 1));
4354 /* We can only get here with a single static member
4356 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
4357 && DECL_STATIC_FUNCTION_P (fn
));
4359 val
= build_address (fn
);
4360 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg
, 0)))
4361 /* Do not lose object's side effects. */
4362 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (val
),
4363 TREE_OPERAND (arg
, 0), val
);
4365 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg
, 1)))
4367 error ("attempt to take address of bit-field structure member %qD",
4368 TREE_OPERAND (arg
, 1));
4369 return error_mark_node
;
4373 tree object
= TREE_OPERAND (arg
, 0);
4374 tree field
= TREE_OPERAND (arg
, 1);
4375 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4376 (TREE_TYPE (object
), decl_type_context (field
)));
4377 val
= build_address (arg
);
4380 if (TREE_CODE (argtype
) == POINTER_TYPE
4381 && TREE_CODE (TREE_TYPE (argtype
)) == METHOD_TYPE
)
4383 build_ptrmemfunc_type (argtype
);
4384 val
= build_ptrmemfunc (argtype
, val
, 0,
4385 /*c_cast_p=*/false);
4397 argtype
= TREE_TYPE (arg
);
4398 return fold_if_not_in_template (build1 (code
, argtype
, arg
));
4401 error ("%s", errstring
);
4402 return error_mark_node
;
4405 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4406 for certain kinds of expressions which are not really lvalues
4407 but which we can accept as lvalues.
4409 If ARG is not a kind of expression we can handle, return
4413 unary_complex_lvalue (enum tree_code code
, tree arg
)
4415 /* Inside a template, making these kinds of adjustments is
4416 pointless; we are only concerned with the type of the
4418 if (processing_template_decl
)
4421 /* Handle (a, b) used as an "lvalue". */
4422 if (TREE_CODE (arg
) == COMPOUND_EXPR
)
4424 tree real_result
= build_unary_op (code
, TREE_OPERAND (arg
, 1), 0);
4425 return build2 (COMPOUND_EXPR
, TREE_TYPE (real_result
),
4426 TREE_OPERAND (arg
, 0), real_result
);
4429 /* Handle (a ? b : c) used as an "lvalue". */
4430 if (TREE_CODE (arg
) == COND_EXPR
4431 || TREE_CODE (arg
) == MIN_EXPR
|| TREE_CODE (arg
) == MAX_EXPR
)
4432 return rationalize_conditional_expr (code
, arg
);
4434 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4435 if (TREE_CODE (arg
) == MODIFY_EXPR
4436 || TREE_CODE (arg
) == PREINCREMENT_EXPR
4437 || TREE_CODE (arg
) == PREDECREMENT_EXPR
)
4439 tree lvalue
= TREE_OPERAND (arg
, 0);
4440 if (TREE_SIDE_EFFECTS (lvalue
))
4442 lvalue
= stabilize_reference (lvalue
);
4443 arg
= build2 (TREE_CODE (arg
), TREE_TYPE (arg
),
4444 lvalue
, TREE_OPERAND (arg
, 1));
4446 return unary_complex_lvalue
4447 (code
, build2 (COMPOUND_EXPR
, TREE_TYPE (lvalue
), arg
, lvalue
));
4450 if (code
!= ADDR_EXPR
)
4453 /* Handle (a = b) used as an "lvalue" for `&'. */
4454 if (TREE_CODE (arg
) == MODIFY_EXPR
4455 || TREE_CODE (arg
) == INIT_EXPR
)
4457 tree real_result
= build_unary_op (code
, TREE_OPERAND (arg
, 0), 0);
4458 arg
= build2 (COMPOUND_EXPR
, TREE_TYPE (real_result
),
4460 TREE_NO_WARNING (arg
) = 1;
4464 if (TREE_CODE (TREE_TYPE (arg
)) == FUNCTION_TYPE
4465 || TREE_CODE (TREE_TYPE (arg
)) == METHOD_TYPE
4466 || TREE_CODE (arg
) == OFFSET_REF
)
4469 /* We permit compiler to make function calls returning
4470 objects of aggregate type look like lvalues. */
4474 if (TREE_CODE (targ
) == SAVE_EXPR
)
4475 targ
= TREE_OPERAND (targ
, 0);
4477 if (TREE_CODE (targ
) == CALL_EXPR
&& IS_AGGR_TYPE (TREE_TYPE (targ
)))
4479 if (TREE_CODE (arg
) == SAVE_EXPR
)
4482 targ
= build_cplus_new (TREE_TYPE (arg
), arg
);
4483 return build1 (ADDR_EXPR
, build_pointer_type (TREE_TYPE (arg
)), targ
);
4486 if (TREE_CODE (arg
) == SAVE_EXPR
&& TREE_CODE (targ
) == INDIRECT_REF
)
4487 return build3 (SAVE_EXPR
, build_pointer_type (TREE_TYPE (arg
)),
4488 TREE_OPERAND (targ
, 0), current_function_decl
, NULL
);
4491 /* Don't let anything else be handled specially. */
4495 /* Mark EXP saying that we need to be able to take the
4496 address of it; it should not be allocated in a register.
4497 Value is true if successful.
4499 C++: we do not allow `current_class_ptr' to be addressable. */
4502 cxx_mark_addressable (tree exp
)
4507 switch (TREE_CODE (x
))
4514 x
= TREE_OPERAND (x
, 0);
4518 if (x
== current_class_ptr
)
4520 error ("cannot take the address of %<this%>, which is an rvalue expression");
4521 TREE_ADDRESSABLE (x
) = 1; /* so compiler doesn't die later. */
4527 /* Caller should not be trying to mark initialized
4528 constant fields addressable. */
4529 gcc_assert (DECL_LANG_SPECIFIC (x
) == 0
4530 || DECL_IN_AGGR_P (x
) == 0
4532 || DECL_EXTERNAL (x
));
4537 if (DECL_REGISTER (x
) && !TREE_ADDRESSABLE (x
)
4538 && !DECL_ARTIFICIAL (x
))
4540 if (TREE_CODE (x
) == VAR_DECL
&& DECL_HARD_REGISTER (x
))
4543 ("address of explicit register variable %qD requested", x
);
4546 else if (extra_warnings
)
4548 (OPT_Wextra
, "address requested for %qD, which is declared %<register%>", x
);
4550 TREE_ADDRESSABLE (x
) = 1;
4554 TREE_ADDRESSABLE (x
) = 1;
4558 TREE_ADDRESSABLE (x
) = 1;
4562 TREE_ADDRESSABLE (x
) = 1;
4563 cxx_mark_addressable (TREE_OPERAND (x
, 0));
4571 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4574 build_x_conditional_expr (tree ifexp
, tree op1
, tree op2
)
4576 tree orig_ifexp
= ifexp
;
4577 tree orig_op1
= op1
;
4578 tree orig_op2
= op2
;
4581 if (processing_template_decl
)
4583 /* The standard says that the expression is type-dependent if
4584 IFEXP is type-dependent, even though the eventual type of the
4585 expression doesn't dependent on IFEXP. */
4586 if (type_dependent_expression_p (ifexp
)
4587 /* As a GNU extension, the middle operand may be omitted. */
4588 || (op1
&& type_dependent_expression_p (op1
))
4589 || type_dependent_expression_p (op2
))
4590 return build_min_nt (COND_EXPR
, ifexp
, op1
, op2
);
4591 ifexp
= build_non_dependent_expr (ifexp
);
4593 op1
= build_non_dependent_expr (op1
);
4594 op2
= build_non_dependent_expr (op2
);
4597 expr
= build_conditional_expr (ifexp
, op1
, op2
);
4598 if (processing_template_decl
&& expr
!= error_mark_node
)
4599 return build_min_non_dep (COND_EXPR
, expr
,
4600 orig_ifexp
, orig_op1
, orig_op2
);
4604 /* Given a list of expressions, return a compound expression
4605 that performs them all and returns the value of the last of them. */
4607 tree
build_x_compound_expr_from_list (tree list
, const char *msg
)
4609 tree expr
= TREE_VALUE (list
);
4611 if (TREE_CHAIN (list
))
4614 pedwarn ("%s expression list treated as compound expression", msg
);
4616 for (list
= TREE_CHAIN (list
); list
; list
= TREE_CHAIN (list
))
4617 expr
= build_x_compound_expr (expr
, TREE_VALUE (list
));
4623 /* Handle overloading of the ',' operator when needed. */
4626 build_x_compound_expr (tree op1
, tree op2
)
4629 tree orig_op1
= op1
;
4630 tree orig_op2
= op2
;
4632 if (processing_template_decl
)
4634 if (type_dependent_expression_p (op1
)
4635 || type_dependent_expression_p (op2
))
4636 return build_min_nt (COMPOUND_EXPR
, op1
, op2
);
4637 op1
= build_non_dependent_expr (op1
);
4638 op2
= build_non_dependent_expr (op2
);
4641 result
= build_new_op (COMPOUND_EXPR
, LOOKUP_NORMAL
, op1
, op2
, NULL_TREE
,
4642 /*overloaded_p=*/NULL
);
4644 result
= build_compound_expr (op1
, op2
);
4646 if (processing_template_decl
&& result
!= error_mark_node
)
4647 return build_min_non_dep (COMPOUND_EXPR
, result
, orig_op1
, orig_op2
);
4652 /* Build a compound expression. */
4655 build_compound_expr (tree lhs
, tree rhs
)
4657 lhs
= convert_to_void (lhs
, "left-hand operand of comma");
4659 if (lhs
== error_mark_node
|| rhs
== error_mark_node
)
4660 return error_mark_node
;
4662 if (TREE_CODE (rhs
) == TARGET_EXPR
)
4664 /* If the rhs is a TARGET_EXPR, then build the compound
4665 expression inside the target_expr's initializer. This
4666 helps the compiler to eliminate unnecessary temporaries. */
4667 tree init
= TREE_OPERAND (rhs
, 1);
4669 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), lhs
, init
);
4670 TREE_OPERAND (rhs
, 1) = init
;
4675 return build2 (COMPOUND_EXPR
, TREE_TYPE (rhs
), lhs
, rhs
);
4678 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
4679 casts away constness. DIAG_FN gives the function to call if we
4680 need to issue a diagnostic; if it is NULL, no diagnostic will be
4681 issued. DESCRIPTION explains what operation is taking place. */
4684 check_for_casting_away_constness (tree src_type
, tree dest_type
,
4685 void (*diag_fn
)(const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2),
4686 const char *description
)
4688 if (diag_fn
&& casts_away_constness (src_type
, dest_type
))
4689 diag_fn ("%s from type %qT to type %qT casts away constness",
4690 description
, src_type
, dest_type
);
4693 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
4694 (another pointer-to-member type in the same hierarchy) and return
4695 the converted expression. If ALLOW_INVERSE_P is permitted, a
4696 pointer-to-derived may be converted to pointer-to-base; otherwise,
4697 only the other direction is permitted. If C_CAST_P is true, this
4698 conversion is taking place as part of a C-style cast. */
4701 convert_ptrmem (tree type
, tree expr
, bool allow_inverse_p
,
4704 if (TYPE_PTRMEM_P (type
))
4708 if (TREE_CODE (expr
) == PTRMEM_CST
)
4709 expr
= cplus_expand_constant (expr
);
4710 delta
= get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr
)),
4711 TYPE_PTRMEM_CLASS_TYPE (type
),
4714 if (!integer_zerop (delta
))
4715 expr
= cp_build_binary_op (PLUS_EXPR
,
4716 build_nop (ptrdiff_type_node
, expr
),
4718 return build_nop (type
, expr
);
4721 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type
), expr
,
4722 allow_inverse_p
, c_cast_p
);
4725 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
4726 a version of EXPR that has TREE_OVERFLOW and/or TREE_CONSTANT_OVERFLOW
4727 set iff they are set in ORIG. Otherwise, return EXPR unchanged. */
4730 ignore_overflows (tree expr
, tree orig
)
4732 if (TREE_CODE (expr
) == INTEGER_CST
4733 && CONSTANT_CLASS_P (orig
)
4734 && TREE_CODE (orig
) != STRING_CST
4735 && (TREE_OVERFLOW (expr
) != TREE_OVERFLOW (orig
)
4736 || TREE_CONSTANT_OVERFLOW (expr
)
4737 != TREE_CONSTANT_OVERFLOW (orig
)))
4739 if (!TREE_OVERFLOW (orig
) && !TREE_CONSTANT_OVERFLOW (orig
))
4740 /* Ensure constant sharing. */
4741 expr
= build_int_cst_wide (TREE_TYPE (expr
),
4742 TREE_INT_CST_LOW (expr
),
4743 TREE_INT_CST_HIGH (expr
));
4746 /* Avoid clobbering a shared constant. */
4747 expr
= copy_node (expr
);
4748 TREE_OVERFLOW (expr
) = TREE_OVERFLOW (orig
);
4749 TREE_CONSTANT_OVERFLOW (expr
)
4750 = TREE_CONSTANT_OVERFLOW (orig
);
4756 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
4757 this static_cast is being attempted as one of the possible casts
4758 allowed by a C-style cast. (In that case, accessibility of base
4759 classes is not considered, and it is OK to cast away
4760 constness.) Return the result of the cast. *VALID_P is set to
4761 indicate whether or not the cast was valid. */
4764 build_static_cast_1 (tree type
, tree expr
, bool c_cast_p
,
4770 void (*diag_fn
)(const char*, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
4773 /* Assume the cast is valid. */
4776 intype
= TREE_TYPE (expr
);
4778 /* Save casted types in the function's used types hash table. */
4779 used_types_insert (type
);
4781 /* Determine what to do when casting away constness. */
4784 /* C-style casts are allowed to cast away constness. With
4785 WARN_CAST_QUAL, we still want to issue a warning. */
4786 diag_fn
= warn_cast_qual
? warning0
: NULL
;
4791 /* A static_cast may not cast away constness. */
4793 desc
= "static_cast";
4796 /* [expr.static.cast]
4798 An lvalue of type "cv1 B", where B is a class type, can be cast
4799 to type "reference to cv2 D", where D is a class derived (clause
4800 _class.derived_) from B, if a valid standard conversion from
4801 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4802 same cv-qualification as, or greater cv-qualification than, cv1,
4803 and B is not a virtual base class of D. */
4804 /* We check this case before checking the validity of "TYPE t =
4805 EXPR;" below because for this case:
4808 struct D : public B { D(const B&); };
4810 void f() { static_cast<const D&>(b); }
4812 we want to avoid constructing a new D. The standard is not
4813 completely clear about this issue, but our interpretation is
4814 consistent with other compilers. */
4815 if (TREE_CODE (type
) == REFERENCE_TYPE
4816 && CLASS_TYPE_P (TREE_TYPE (type
))
4817 && CLASS_TYPE_P (intype
)
4818 && real_lvalue_p (expr
)
4819 && DERIVED_FROM_P (intype
, TREE_TYPE (type
))
4820 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype
)),
4821 build_pointer_type (TYPE_MAIN_VARIANT
4822 (TREE_TYPE (type
))))
4824 || at_least_as_qualified_p (TREE_TYPE (type
), intype
)))
4828 /* There is a standard conversion from "D*" to "B*" even if "B"
4829 is ambiguous or inaccessible. If this is really a
4830 static_cast, then we check both for inaccessibility and
4831 ambiguity. However, if this is a static_cast being performed
4832 because the user wrote a C-style cast, then accessibility is
4834 base
= lookup_base (TREE_TYPE (type
), intype
,
4835 c_cast_p
? ba_unique
: ba_check
,
4838 /* Convert from "B*" to "D*". This function will check that "B"
4839 is not a virtual base of "D". */
4840 expr
= build_base_path (MINUS_EXPR
, build_address (expr
),
4841 base
, /*nonnull=*/false);
4842 /* Convert the pointer to a reference -- but then remember that
4843 there are no expressions with reference type in C++. */
4844 return convert_from_reference (build_nop (type
, expr
));
4849 /* [expr.static.cast]
4851 An expression e can be explicitly converted to a type T using a
4852 static_cast of the form static_cast<T>(e) if the declaration T
4853 t(e);" is well-formed, for some invented temporary variable
4855 result
= perform_direct_initialization_if_possible (type
, expr
,
4859 result
= convert_from_reference (result
);
4861 /* Ignore any integer overflow caused by the cast. */
4862 result
= ignore_overflows (result
, orig
);
4864 /* [expr.static.cast]
4866 If T is a reference type, the result is an lvalue; otherwise,
4867 the result is an rvalue. */
4868 if (TREE_CODE (type
) != REFERENCE_TYPE
)
4869 result
= rvalue (result
);
4873 /* [expr.static.cast]
4875 Any expression can be explicitly converted to type cv void. */
4876 if (TREE_CODE (type
) == VOID_TYPE
)
4877 return convert_to_void (expr
, /*implicit=*/NULL
);
4879 /* [expr.static.cast]
4881 The inverse of any standard conversion sequence (clause _conv_),
4882 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4883 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4884 (_conv.bool_) conversions, can be performed explicitly using
4885 static_cast subject to the restriction that the explicit
4886 conversion does not cast away constness (_expr.const.cast_), and
4887 the following additional rules for specific cases: */
4888 /* For reference, the conversions not excluded are: integral
4889 promotions, floating point promotion, integral conversions,
4890 floating point conversions, floating-integral conversions,
4891 pointer conversions, and pointer to member conversions. */
4894 A value of integral _or enumeration_ type can be explicitly
4895 converted to an enumeration type. */
4896 /* The effect of all that is that any conversion between any two
4897 types which are integral, floating, or enumeration types can be
4899 if ((INTEGRAL_TYPE_P (type
) || SCALAR_FLOAT_TYPE_P (type
))
4900 && (INTEGRAL_TYPE_P (intype
) || SCALAR_FLOAT_TYPE_P (intype
)))
4902 expr
= ocp_convert (type
, expr
, CONV_C_CAST
, LOOKUP_NORMAL
);
4904 /* Ignore any integer overflow caused by the cast. */
4905 expr
= ignore_overflows (expr
, orig
);
4909 if (TYPE_PTR_P (type
) && TYPE_PTR_P (intype
)
4910 && CLASS_TYPE_P (TREE_TYPE (type
))
4911 && CLASS_TYPE_P (TREE_TYPE (intype
))
4912 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4913 (TREE_TYPE (intype
))),
4914 build_pointer_type (TYPE_MAIN_VARIANT
4915 (TREE_TYPE (type
)))))
4920 check_for_casting_away_constness (intype
, type
, diag_fn
, desc
);
4921 base
= lookup_base (TREE_TYPE (type
), TREE_TYPE (intype
),
4922 c_cast_p
? ba_unique
: ba_check
,
4924 return build_base_path (MINUS_EXPR
, expr
, base
, /*nonnull=*/false);
4927 if ((TYPE_PTRMEM_P (type
) && TYPE_PTRMEM_P (intype
))
4928 || (TYPE_PTRMEMFUNC_P (type
) && TYPE_PTRMEMFUNC_P (intype
)))
4935 c1
= TYPE_PTRMEM_CLASS_TYPE (intype
);
4936 c2
= TYPE_PTRMEM_CLASS_TYPE (type
);
4938 if (TYPE_PTRMEM_P (type
))
4940 t1
= (build_ptrmem_type
4942 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype
))));
4943 t2
= (build_ptrmem_type
4945 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type
))));
4952 if (can_convert (t1
, t2
))
4955 check_for_casting_away_constness (intype
, type
, diag_fn
,
4957 return convert_ptrmem (type
, expr
, /*allow_inverse_p=*/1,
4962 /* [expr.static.cast]
4964 An rvalue of type "pointer to cv void" can be explicitly
4965 converted to a pointer to object type. A value of type pointer
4966 to object converted to "pointer to cv void" and back to the
4967 original pointer type will have its original value. */
4968 if (TREE_CODE (intype
) == POINTER_TYPE
4969 && VOID_TYPE_P (TREE_TYPE (intype
))
4970 && TYPE_PTROB_P (type
))
4973 check_for_casting_away_constness (intype
, type
, diag_fn
, desc
);
4974 return build_nop (type
, expr
);
4978 return error_mark_node
;
4981 /* Return an expression representing static_cast<TYPE>(EXPR). */
4984 build_static_cast (tree type
, tree expr
)
4989 if (type
== error_mark_node
|| expr
== error_mark_node
)
4990 return error_mark_node
;
4992 if (processing_template_decl
)
4994 expr
= build_min (STATIC_CAST_EXPR
, type
, expr
);
4995 /* We don't know if it will or will not have side effects. */
4996 TREE_SIDE_EFFECTS (expr
) = 1;
4997 return convert_from_reference (expr
);
5000 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5001 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5002 if (TREE_CODE (type
) != REFERENCE_TYPE
5003 && TREE_CODE (expr
) == NOP_EXPR
5004 && TREE_TYPE (expr
) == TREE_TYPE (TREE_OPERAND (expr
, 0)))
5005 expr
= TREE_OPERAND (expr
, 0);
5007 result
= build_static_cast_1 (type
, expr
, /*c_cast_p=*/false, &valid_p
);
5011 error ("invalid static_cast from type %qT to type %qT",
5012 TREE_TYPE (expr
), type
);
5013 return error_mark_node
;
5016 /* EXPR is an expression with member function or pointer-to-member
5017 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5018 not permitted by ISO C++, but we accept it in some modes. If we
5019 are not in one of those modes, issue a diagnostic. Return the
5020 converted expression. */
5023 convert_member_func_to_ptr (tree type
, tree expr
)
5028 intype
= TREE_TYPE (expr
);
5029 gcc_assert (TYPE_PTRMEMFUNC_P (intype
)
5030 || TREE_CODE (intype
) == METHOD_TYPE
);
5032 if (pedantic
|| warn_pmf2ptr
)
5033 pedwarn ("converting from %qT to %qT", intype
, type
);
5035 if (TREE_CODE (intype
) == METHOD_TYPE
)
5036 expr
= build_addr_func (expr
);
5037 else if (TREE_CODE (expr
) == PTRMEM_CST
)
5038 expr
= build_address (PTRMEM_CST_MEMBER (expr
));
5041 decl
= maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype
), 0);
5042 decl
= build_address (decl
);
5043 expr
= get_member_function_from_ptrfunc (&decl
, expr
);
5046 return build_nop (type
, expr
);
5049 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5050 If C_CAST_P is true, this reinterpret cast is being done as part of
5051 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5052 indicate whether or not reinterpret_cast was valid. */
5055 build_reinterpret_cast_1 (tree type
, tree expr
, bool c_cast_p
,
5060 /* Assume the cast is invalid. */
5064 if (type
== error_mark_node
|| error_operand_p (expr
))
5065 return error_mark_node
;
5067 intype
= TREE_TYPE (expr
);
5069 /* Save casted types in the function's used types hash table. */
5070 used_types_insert (type
);
5072 /* [expr.reinterpret.cast]
5073 An lvalue expression of type T1 can be cast to the type
5074 "reference to T2" if an expression of type "pointer to T1" can be
5075 explicitly converted to the type "pointer to T2" using a
5076 reinterpret_cast. */
5077 if (TREE_CODE (type
) == REFERENCE_TYPE
)
5079 if (! real_lvalue_p (expr
))
5081 error ("invalid cast of an rvalue expression of type "
5084 return error_mark_node
;
5087 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5088 "B" are related class types; the reinterpret_cast does not
5089 adjust the pointer. */
5090 if (TYPE_PTR_P (intype
)
5091 && (comptypes (TREE_TYPE (intype
), TREE_TYPE (type
),
5092 COMPARE_BASE
| COMPARE_DERIVED
)))
5093 warning (0, "casting %qT to %qT does not dereference pointer",
5096 expr
= build_unary_op (ADDR_EXPR
, expr
, 0);
5097 if (expr
!= error_mark_node
)
5098 expr
= build_reinterpret_cast_1
5099 (build_pointer_type (TREE_TYPE (type
)), expr
, c_cast_p
,
5101 if (expr
!= error_mark_node
)
5102 expr
= build_indirect_ref (expr
, 0);
5106 /* As a G++ extension, we consider conversions from member
5107 functions, and pointers to member functions to
5108 pointer-to-function and pointer-to-void types. If
5109 -Wno-pmf-conversions has not been specified,
5110 convert_member_func_to_ptr will issue an error message. */
5111 if ((TYPE_PTRMEMFUNC_P (intype
)
5112 || TREE_CODE (intype
) == METHOD_TYPE
)
5113 && TYPE_PTR_P (type
)
5114 && (TREE_CODE (TREE_TYPE (type
)) == FUNCTION_TYPE
5115 || VOID_TYPE_P (TREE_TYPE (type
))))
5116 return convert_member_func_to_ptr (type
, expr
);
5118 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5119 array-to-pointer, and function-to-pointer conversions are
5121 expr
= decay_conversion (expr
);
5123 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5124 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5125 if (TREE_CODE (expr
) == NOP_EXPR
5126 && TREE_TYPE (expr
) == TREE_TYPE (TREE_OPERAND (expr
, 0)))
5127 expr
= TREE_OPERAND (expr
, 0);
5129 if (error_operand_p (expr
))
5130 return error_mark_node
;
5132 intype
= TREE_TYPE (expr
);
5134 /* [expr.reinterpret.cast]
5135 A pointer can be converted to any integral type large enough to
5137 if (CP_INTEGRAL_TYPE_P (type
) && TYPE_PTR_P (intype
))
5139 if (TYPE_PRECISION (type
) < TYPE_PRECISION (intype
))
5140 pedwarn ("cast from %qT to %qT loses precision",
5143 /* [expr.reinterpret.cast]
5144 A value of integral or enumeration type can be explicitly
5145 converted to a pointer. */
5146 else if (TYPE_PTR_P (type
) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype
))
5149 else if ((TYPE_PTRFN_P (type
) && TYPE_PTRFN_P (intype
))
5150 || (TYPE_PTRMEMFUNC_P (type
) && TYPE_PTRMEMFUNC_P (intype
)))
5151 return fold_if_not_in_template (build_nop (type
, expr
));
5152 else if ((TYPE_PTRMEM_P (type
) && TYPE_PTRMEM_P (intype
))
5153 || (TYPE_PTROBV_P (type
) && TYPE_PTROBV_P (intype
)))
5158 check_for_casting_away_constness (intype
, type
, error
,
5159 "reinterpret_cast");
5160 /* Warn about possible alignment problems. */
5161 if (STRICT_ALIGNMENT
&& warn_cast_align
5162 && !VOID_TYPE_P (type
)
5163 && TREE_CODE (TREE_TYPE (intype
)) != FUNCTION_TYPE
5164 && COMPLETE_TYPE_P (TREE_TYPE (type
))
5165 && COMPLETE_TYPE_P (TREE_TYPE (intype
))
5166 && TYPE_ALIGN (TREE_TYPE (type
)) > TYPE_ALIGN (TREE_TYPE (intype
)))
5167 warning (0, "cast from %qT to %qT increases required alignment of "
5171 /* We need to strip nops here, because the frontend likes to
5172 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5174 strict_aliasing_warning (intype
, type
, sexpr
);
5176 return fold_if_not_in_template (build_nop (type
, expr
));
5178 else if ((TYPE_PTRFN_P (type
) && TYPE_PTROBV_P (intype
))
5179 || (TYPE_PTRFN_P (intype
) && TYPE_PTROBV_P (type
)))
5182 /* Only issue a warning, as we have always supported this
5183 where possible, and it is necessary in some cases. DR 195
5184 addresses this issue, but as of 2004/10/26 is still in
5186 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5187 return fold_if_not_in_template (build_nop (type
, expr
));
5189 else if (TREE_CODE (type
) == VECTOR_TYPE
)
5190 return fold_if_not_in_template (convert_to_vector (type
, expr
));
5191 else if (TREE_CODE (intype
) == VECTOR_TYPE
)
5192 return fold_if_not_in_template (convert_to_integer (type
, expr
));
5197 error ("invalid cast from type %qT to type %qT", intype
, type
);
5198 return error_mark_node
;
5201 return cp_convert (type
, expr
);
5205 build_reinterpret_cast (tree type
, tree expr
)
5207 if (type
== error_mark_node
|| expr
== error_mark_node
)
5208 return error_mark_node
;
5210 if (processing_template_decl
)
5212 tree t
= build_min (REINTERPRET_CAST_EXPR
, type
, expr
);
5214 if (!TREE_SIDE_EFFECTS (t
)
5215 && type_dependent_expression_p (expr
))
5216 /* There might turn out to be side effects inside expr. */
5217 TREE_SIDE_EFFECTS (t
) = 1;
5218 return convert_from_reference (t
);
5221 return build_reinterpret_cast_1 (type
, expr
, /*c_cast_p=*/false,
5225 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5226 return an appropriate expression. Otherwise, return
5227 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5228 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5229 performing a C-style cast, its value upon return will indicate
5230 whether or not the conversion succeeded. */
5233 build_const_cast_1 (tree dst_type
, tree expr
, bool complain
,
5237 tree reference_type
;
5239 /* Callers are responsible for handling error_mark_node as a
5240 destination type. */
5241 gcc_assert (dst_type
!= error_mark_node
);
5242 /* In a template, callers should be building syntactic
5243 representations of casts, not using this machinery. */
5244 gcc_assert (!processing_template_decl
);
5246 /* Assume the conversion is invalid. */
5250 if (!POINTER_TYPE_P (dst_type
) && !TYPE_PTRMEM_P (dst_type
))
5253 error ("invalid use of const_cast with type %qT, "
5254 "which is not a pointer, "
5255 "reference, nor a pointer-to-data-member type", dst_type
);
5256 return error_mark_node
;
5259 if (TREE_CODE (TREE_TYPE (dst_type
)) == FUNCTION_TYPE
)
5262 error ("invalid use of const_cast with type %qT, which is a pointer "
5263 "or reference to a function type", dst_type
);
5264 return error_mark_node
;
5267 /* Save casted types in the function's used types hash table. */
5268 used_types_insert (dst_type
);
5270 src_type
= TREE_TYPE (expr
);
5271 /* Expressions do not really have reference types. */
5272 if (TREE_CODE (src_type
) == REFERENCE_TYPE
)
5273 src_type
= TREE_TYPE (src_type
);
5275 /* [expr.const.cast]
5277 An lvalue of type T1 can be explicitly converted to an lvalue of
5278 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5279 types) if a pointer to T1 can be explicitly converted to the type
5280 pointer to T2 using a const_cast. */
5281 if (TREE_CODE (dst_type
) == REFERENCE_TYPE
)
5283 reference_type
= dst_type
;
5284 if (! real_lvalue_p (expr
))
5287 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5288 src_type
, dst_type
);
5289 return error_mark_node
;
5291 dst_type
= build_pointer_type (TREE_TYPE (dst_type
));
5292 src_type
= build_pointer_type (src_type
);
5296 reference_type
= NULL_TREE
;
5297 /* If the destination type is not a reference type, the
5298 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5299 conversions are performed. */
5300 src_type
= type_decays_to (src_type
);
5301 if (src_type
== error_mark_node
)
5302 return error_mark_node
;
5305 if ((TYPE_PTR_P (src_type
) || TYPE_PTRMEM_P (src_type
))
5306 && comp_ptr_ttypes_const (dst_type
, src_type
))
5311 /* This cast is actually a C-style cast. Issue a warning if
5312 the user is making a potentially unsafe cast. */
5314 check_for_casting_away_constness (src_type
, dst_type
,
5320 expr
= build_unary_op (ADDR_EXPR
, expr
, 0);
5321 expr
= build_nop (reference_type
, expr
);
5322 return convert_from_reference (expr
);
5326 expr
= decay_conversion (expr
);
5327 /* build_c_cast puts on a NOP_EXPR to make the result not an
5328 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5329 non-lvalue context. */
5330 if (TREE_CODE (expr
) == NOP_EXPR
5331 && TREE_TYPE (expr
) == TREE_TYPE (TREE_OPERAND (expr
, 0)))
5332 expr
= TREE_OPERAND (expr
, 0);
5333 return build_nop (dst_type
, expr
);
5338 error ("invalid const_cast from type %qT to type %qT",
5339 src_type
, dst_type
);
5340 return error_mark_node
;
5344 build_const_cast (tree type
, tree expr
)
5346 if (type
== error_mark_node
|| error_operand_p (expr
))
5347 return error_mark_node
;
5349 if (processing_template_decl
)
5351 tree t
= build_min (CONST_CAST_EXPR
, type
, expr
);
5353 if (!TREE_SIDE_EFFECTS (t
)
5354 && type_dependent_expression_p (expr
))
5355 /* There might turn out to be side effects inside expr. */
5356 TREE_SIDE_EFFECTS (t
) = 1;
5357 return convert_from_reference (t
);
5360 return build_const_cast_1 (type
, expr
, /*complain=*/true,
5364 /* Build an expression representing an explicit C-style cast to type
5365 TYPE of expression EXPR. */
5368 build_c_cast (tree type
, tree expr
)
5374 if (type
== error_mark_node
|| error_operand_p (expr
))
5375 return error_mark_node
;
5377 if (processing_template_decl
)
5379 tree t
= build_min (CAST_EXPR
, type
,
5380 tree_cons (NULL_TREE
, value
, NULL_TREE
));
5381 /* We don't know if it will or will not have side effects. */
5382 TREE_SIDE_EFFECTS (t
) = 1;
5383 return convert_from_reference (t
);
5386 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5387 'Class') should always be retained, because this information aids
5388 in method lookup. */
5389 if (objc_is_object_ptr (type
)
5390 && objc_is_object_ptr (TREE_TYPE (expr
)))
5391 return build_nop (type
, expr
);
5393 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5394 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5395 if (TREE_CODE (type
) != REFERENCE_TYPE
5396 && TREE_CODE (value
) == NOP_EXPR
5397 && TREE_TYPE (value
) == TREE_TYPE (TREE_OPERAND (value
, 0)))
5398 value
= TREE_OPERAND (value
, 0);
5400 if (TREE_CODE (type
) == ARRAY_TYPE
)
5402 /* Allow casting from T1* to T2[] because Cfront allows it.
5403 NIHCL uses it. It is not valid ISO C++ however. */
5404 if (TREE_CODE (TREE_TYPE (expr
)) == POINTER_TYPE
)
5406 pedwarn ("ISO C++ forbids casting to an array type %qT", type
);
5407 type
= build_pointer_type (TREE_TYPE (type
));
5411 error ("ISO C++ forbids casting to an array type %qT", type
);
5412 return error_mark_node
;
5416 if (TREE_CODE (type
) == FUNCTION_TYPE
5417 || TREE_CODE (type
) == METHOD_TYPE
)
5419 error ("invalid cast to function type %qT", type
);
5420 return error_mark_node
;
5423 /* A C-style cast can be a const_cast. */
5424 result
= build_const_cast_1 (type
, value
, /*complain=*/false,
5429 /* Or a static cast. */
5430 result
= build_static_cast_1 (type
, value
, /*c_cast_p=*/true,
5432 /* Or a reinterpret_cast. */
5434 result
= build_reinterpret_cast_1 (type
, value
, /*c_cast_p=*/true,
5436 /* The static_cast or reinterpret_cast may be followed by a
5439 /* A valid cast may result in errors if, for example, a
5440 conversion to am ambiguous base class is required. */
5441 && !error_operand_p (result
))
5445 /* Non-class rvalues always have cv-unqualified type. */
5446 if (!CLASS_TYPE_P (type
))
5447 type
= TYPE_MAIN_VARIANT (type
);
5448 result_type
= TREE_TYPE (result
);
5449 if (!CLASS_TYPE_P (result_type
))
5450 result_type
= TYPE_MAIN_VARIANT (result_type
);
5451 /* If the type of RESULT does not match TYPE, perform a
5452 const_cast to make it match. If the static_cast or
5453 reinterpret_cast succeeded, we will differ by at most
5454 cv-qualification, so the follow-on const_cast is guaranteed
5456 if (!same_type_p (non_reference (type
), non_reference (result_type
)))
5458 result
= build_const_cast_1 (type
, result
, false, &valid_p
);
5459 gcc_assert (valid_p
);
5464 return error_mark_node
;
5467 /* Build an assignment expression of lvalue LHS from value RHS.
5468 MODIFYCODE is the code for a binary operator that we use
5469 to combine the old value of LHS with RHS to get the new value.
5470 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5472 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5475 build_modify_expr (tree lhs
, enum tree_code modifycode
, tree rhs
)
5479 tree lhstype
= TREE_TYPE (lhs
);
5480 tree olhstype
= lhstype
;
5481 tree olhs
= NULL_TREE
;
5482 bool plain_assign
= (modifycode
== NOP_EXPR
);
5484 /* Avoid duplicate error messages from operands that had errors. */
5485 if (error_operand_p (lhs
) || error_operand_p (rhs
))
5486 return error_mark_node
;
5488 /* Handle control structure constructs used as "lvalues". */
5489 switch (TREE_CODE (lhs
))
5491 /* Handle --foo = 5; as these are valid constructs in C++. */
5492 case PREDECREMENT_EXPR
:
5493 case PREINCREMENT_EXPR
:
5494 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs
, 0)))
5495 lhs
= build2 (TREE_CODE (lhs
), TREE_TYPE (lhs
),
5496 stabilize_reference (TREE_OPERAND (lhs
, 0)),
5497 TREE_OPERAND (lhs
, 1));
5498 return build2 (COMPOUND_EXPR
, lhstype
,
5500 build_modify_expr (TREE_OPERAND (lhs
, 0),
5503 /* Handle (a, b) used as an "lvalue". */
5505 newrhs
= build_modify_expr (TREE_OPERAND (lhs
, 1),
5507 if (newrhs
== error_mark_node
)
5508 return error_mark_node
;
5509 return build2 (COMPOUND_EXPR
, lhstype
,
5510 TREE_OPERAND (lhs
, 0), newrhs
);
5513 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs
, 0)))
5514 lhs
= build2 (TREE_CODE (lhs
), TREE_TYPE (lhs
),
5515 stabilize_reference (TREE_OPERAND (lhs
, 0)),
5516 TREE_OPERAND (lhs
, 1));
5517 newrhs
= build_modify_expr (TREE_OPERAND (lhs
, 0), modifycode
, rhs
);
5518 if (newrhs
== error_mark_node
)
5519 return error_mark_node
;
5520 return build2 (COMPOUND_EXPR
, lhstype
, lhs
, newrhs
);
5524 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
5525 when neither operand has side-effects. */
5526 if (!lvalue_or_else (lhs
, lv_assign
))
5527 return error_mark_node
;
5529 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs
, 0))
5530 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs
, 1)));
5532 lhs
= build3 (COND_EXPR
, TREE_TYPE (lhs
),
5533 build2 (TREE_CODE (lhs
) == MIN_EXPR
? LE_EXPR
: GE_EXPR
,
5535 TREE_OPERAND (lhs
, 0),
5536 TREE_OPERAND (lhs
, 1)),
5537 TREE_OPERAND (lhs
, 0),
5538 TREE_OPERAND (lhs
, 1));
5541 /* Handle (a ? b : c) used as an "lvalue". */
5544 /* Produce (a ? (b = rhs) : (c = rhs))
5545 except that the RHS goes through a save-expr
5546 so the code to compute it is only emitted once. */
5548 tree preeval
= NULL_TREE
;
5550 rhs
= stabilize_expr (rhs
, &preeval
);
5552 /* Check this here to avoid odd errors when trying to convert
5553 a throw to the type of the COND_EXPR. */
5554 if (!lvalue_or_else (lhs
, lv_assign
))
5555 return error_mark_node
;
5557 cond
= build_conditional_expr
5558 (TREE_OPERAND (lhs
, 0),
5559 build_modify_expr (TREE_OPERAND (lhs
, 1),
5561 build_modify_expr (TREE_OPERAND (lhs
, 2),
5564 if (cond
== error_mark_node
)
5566 /* Make sure the code to compute the rhs comes out
5567 before the split. */
5569 cond
= build2 (COMPOUND_EXPR
, TREE_TYPE (lhs
), preeval
, cond
);
5577 if (modifycode
== INIT_EXPR
)
5579 if (TREE_CODE (rhs
) == CONSTRUCTOR
)
5581 if (! same_type_p (TREE_TYPE (rhs
), lhstype
))
5582 /* Call convert to generate an error; see PR 11063. */
5583 rhs
= convert (lhstype
, rhs
);
5584 result
= build2 (INIT_EXPR
, lhstype
, lhs
, rhs
);
5585 TREE_SIDE_EFFECTS (result
) = 1;
5588 else if (! IS_AGGR_TYPE (lhstype
))
5589 /* Do the default thing. */;
5592 result
= build_special_member_call (lhs
, complete_ctor_identifier
,
5593 build_tree_list (NULL_TREE
, rhs
),
5594 lhstype
, LOOKUP_NORMAL
);
5595 if (result
== NULL_TREE
)
5596 return error_mark_node
;
5602 lhs
= require_complete_type (lhs
);
5603 if (lhs
== error_mark_node
)
5604 return error_mark_node
;
5606 if (modifycode
== NOP_EXPR
)
5608 /* `operator=' is not an inheritable operator. */
5609 if (! IS_AGGR_TYPE (lhstype
))
5610 /* Do the default thing. */;
5613 result
= build_new_op (MODIFY_EXPR
, LOOKUP_NORMAL
,
5614 lhs
, rhs
, make_node (NOP_EXPR
),
5615 /*overloaded_p=*/NULL
);
5616 if (result
== NULL_TREE
)
5617 return error_mark_node
;
5624 /* A binary op has been requested. Combine the old LHS
5625 value with the RHS producing the value we should actually
5626 store into the LHS. */
5628 gcc_assert (!PROMOTES_TO_AGGR_TYPE (lhstype
, REFERENCE_TYPE
));
5629 lhs
= stabilize_reference (lhs
);
5630 newrhs
= cp_build_binary_op (modifycode
, lhs
, rhs
);
5631 if (newrhs
== error_mark_node
)
5633 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode
,
5634 TREE_TYPE (lhs
), TREE_TYPE (rhs
));
5635 return error_mark_node
;
5638 /* Now it looks like a plain assignment. */
5639 modifycode
= NOP_EXPR
;
5641 gcc_assert (TREE_CODE (lhstype
) != REFERENCE_TYPE
);
5642 gcc_assert (TREE_CODE (TREE_TYPE (newrhs
)) != REFERENCE_TYPE
);
5645 /* The left-hand side must be an lvalue. */
5646 if (!lvalue_or_else (lhs
, lv_assign
))
5647 return error_mark_node
;
5649 /* Warn about modifying something that is `const'. Don't warn if
5650 this is initialization. */
5651 if (modifycode
!= INIT_EXPR
5652 && (TREE_READONLY (lhs
) || CP_TYPE_CONST_P (lhstype
)
5653 /* Functions are not modifiable, even though they are
5655 || TREE_CODE (TREE_TYPE (lhs
)) == FUNCTION_TYPE
5656 || TREE_CODE (TREE_TYPE (lhs
)) == METHOD_TYPE
5657 /* If it's an aggregate and any field is const, then it is
5658 effectively const. */
5659 || (CLASS_TYPE_P (lhstype
)
5660 && C_TYPE_FIELDS_READONLY (lhstype
))))
5661 readonly_error (lhs
, "assignment", 0);
5663 /* If storing into a structure or union member, it has probably been
5664 given type `int'. Compute the type that would go with the actual
5665 amount of storage the member occupies. */
5667 if (TREE_CODE (lhs
) == COMPONENT_REF
5668 && (TREE_CODE (lhstype
) == INTEGER_TYPE
5669 || TREE_CODE (lhstype
) == REAL_TYPE
5670 || TREE_CODE (lhstype
) == ENUMERAL_TYPE
))
5672 lhstype
= TREE_TYPE (get_unwidened (lhs
, 0));
5674 /* If storing in a field that is in actuality a short or narrower
5675 than one, we must store in the field in its actual type. */
5677 if (lhstype
!= TREE_TYPE (lhs
))
5679 /* Avoid warnings converting integral types back into enums for
5681 if (TREE_CODE (lhstype
) == INTEGER_TYPE
5682 && TREE_CODE (olhstype
) == ENUMERAL_TYPE
)
5684 if (TREE_SIDE_EFFECTS (lhs
))
5685 lhs
= stabilize_reference (lhs
);
5688 lhs
= copy_node (lhs
);
5689 TREE_TYPE (lhs
) = lhstype
;
5693 /* Convert new value to destination type. */
5695 if (TREE_CODE (lhstype
) == ARRAY_TYPE
)
5699 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype
),
5700 TYPE_MAIN_VARIANT (TREE_TYPE (rhs
))))
5702 error ("incompatible types in assignment of %qT to %qT",
5703 TREE_TYPE (rhs
), lhstype
);
5704 return error_mark_node
;
5707 /* Allow array assignment in compiler-generated code. */
5708 if (! DECL_ARTIFICIAL (current_function_decl
))
5709 pedwarn ("ISO C++ forbids assignment of arrays");
5711 from_array
= TREE_CODE (TREE_TYPE (newrhs
)) == ARRAY_TYPE
5712 ? 1 + (modifycode
!= INIT_EXPR
): 0;
5713 return build_vec_init (lhs
, NULL_TREE
, newrhs
,
5714 /*explicit_default_init_p=*/false,
5718 if (modifycode
== INIT_EXPR
)
5719 newrhs
= convert_for_initialization (lhs
, lhstype
, newrhs
, LOOKUP_NORMAL
,
5720 "initialization", NULL_TREE
, 0);
5723 /* Avoid warnings on enum bit fields. */
5724 if (TREE_CODE (olhstype
) == ENUMERAL_TYPE
5725 && TREE_CODE (lhstype
) == INTEGER_TYPE
)
5727 newrhs
= convert_for_assignment (olhstype
, newrhs
, "assignment",
5729 newrhs
= convert_force (lhstype
, newrhs
, 0);
5732 newrhs
= convert_for_assignment (lhstype
, newrhs
, "assignment",
5734 if (TREE_CODE (newrhs
) == CALL_EXPR
5735 && TYPE_NEEDS_CONSTRUCTING (lhstype
))
5736 newrhs
= build_cplus_new (lhstype
, newrhs
);
5738 /* Can't initialize directly from a TARGET_EXPR, since that would
5739 cause the lhs to be constructed twice, and possibly result in
5740 accidental self-initialization. So we force the TARGET_EXPR to be
5741 expanded without a target. */
5742 if (TREE_CODE (newrhs
) == TARGET_EXPR
)
5743 newrhs
= build2 (COMPOUND_EXPR
, TREE_TYPE (newrhs
), newrhs
,
5744 TREE_OPERAND (newrhs
, 0));
5747 if (newrhs
== error_mark_node
)
5748 return error_mark_node
;
5750 if (c_dialect_objc () && flag_objc_gc
)
5752 result
= objc_generate_write_barrier (lhs
, modifycode
, newrhs
);
5758 result
= build2 (modifycode
== NOP_EXPR
? MODIFY_EXPR
: INIT_EXPR
,
5759 lhstype
, lhs
, newrhs
);
5761 TREE_SIDE_EFFECTS (result
) = 1;
5763 TREE_NO_WARNING (result
) = 1;
5765 /* If we got the LHS in a different type for storing in,
5766 convert the result back to the nominal type of LHS
5767 so that the value we return always has the same type
5768 as the LHS argument. */
5770 if (olhstype
== TREE_TYPE (result
))
5774 result
= build2 (COMPOUND_EXPR
, olhstype
, result
, olhs
);
5775 TREE_NO_WARNING (result
) = 1;
5778 return convert_for_assignment (olhstype
, result
, "assignment",
5783 build_x_modify_expr (tree lhs
, enum tree_code modifycode
, tree rhs
)
5785 if (processing_template_decl
)
5786 return build_min_nt (MODOP_EXPR
, lhs
,
5787 build_min_nt (modifycode
, NULL_TREE
, NULL_TREE
), rhs
);
5789 if (modifycode
!= NOP_EXPR
)
5791 tree rval
= build_new_op (MODIFY_EXPR
, LOOKUP_NORMAL
, lhs
, rhs
,
5792 make_node (modifycode
),
5793 /*overloaded_p=*/NULL
);
5796 TREE_NO_WARNING (rval
) = 1;
5800 return build_modify_expr (lhs
, modifycode
, rhs
);
5804 /* Get difference in deltas for different pointer to member function
5805 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5806 the conversion is invalid, the constant is zero. If
5807 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
5808 If C_CAST_P is true this conversion is taking place as part of a
5811 Note that the naming of FROM and TO is kind of backwards; the return
5812 value is what we add to a TO in order to get a FROM. They are named
5813 this way because we call this function to find out how to convert from
5814 a pointer to member of FROM to a pointer to member of TO. */
5817 get_delta_difference (tree from
, tree to
,
5818 bool allow_inverse_p
,
5825 /* Assume no conversion is required. */
5826 result
= integer_zero_node
;
5827 binfo
= lookup_base (to
, from
, c_cast_p
? ba_unique
: ba_check
, &kind
);
5828 if (kind
== bk_inaccessible
|| kind
== bk_ambig
)
5829 error (" in pointer to member function conversion");
5832 if (kind
!= bk_via_virtual
)
5833 result
= BINFO_OFFSET (binfo
);
5836 tree virt_binfo
= binfo_from_vbase (binfo
);
5838 /* This is a reinterpret cast, we choose to do nothing. */
5839 if (allow_inverse_p
)
5840 warning (0, "pointer to member cast via virtual base %qT",
5841 BINFO_TYPE (virt_binfo
));
5843 error ("pointer to member conversion via virtual base %qT",
5844 BINFO_TYPE (virt_binfo
));
5847 else if (same_type_ignoring_top_level_qualifiers_p (from
, to
))
5848 /* Pointer to member of incomplete class is permitted*/;
5849 else if (!allow_inverse_p
)
5851 error_not_base_type (from
, to
);
5852 error (" in pointer to member conversion");
5856 binfo
= lookup_base (from
, to
, c_cast_p
? ba_unique
: ba_check
, &kind
);
5859 if (kind
!= bk_via_virtual
)
5860 result
= size_diffop (size_zero_node
, BINFO_OFFSET (binfo
));
5863 /* This is a reinterpret cast, we choose to do nothing. */
5864 tree virt_binfo
= binfo_from_vbase (binfo
);
5866 warning (0, "pointer to member cast via virtual base %qT",
5867 BINFO_TYPE (virt_binfo
));
5872 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node
,
5876 /* Return a constructor for the pointer-to-member-function TYPE using
5877 the other components as specified. */
5880 build_ptrmemfunc1 (tree type
, tree delta
, tree pfn
)
5885 VEC(constructor_elt
, gc
) *v
;
5887 /* Pull the FIELD_DECLs out of the type. */
5888 pfn_field
= TYPE_FIELDS (type
);
5889 delta_field
= TREE_CHAIN (pfn_field
);
5891 /* Make sure DELTA has the type we want. */
5892 delta
= convert_and_check (delta_type_node
, delta
);
5894 /* Finish creating the initializer. */
5895 v
= VEC_alloc(constructor_elt
, gc
, 2);
5896 CONSTRUCTOR_APPEND_ELT(v
, pfn_field
, pfn
);
5897 CONSTRUCTOR_APPEND_ELT(v
, delta_field
, delta
);
5898 u
= build_constructor (type
, v
);
5899 TREE_CONSTANT (u
) = TREE_CONSTANT (pfn
) & TREE_CONSTANT (delta
);
5900 TREE_INVARIANT (u
) = TREE_INVARIANT (pfn
) & TREE_INVARIANT (delta
);
5901 TREE_STATIC (u
) = (TREE_CONSTANT (u
)
5902 && (initializer_constant_valid_p (pfn
, TREE_TYPE (pfn
))
5904 && (initializer_constant_valid_p (delta
, TREE_TYPE (delta
))
5909 /* Build a constructor for a pointer to member function. It can be
5910 used to initialize global variables, local variable, or used
5911 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5914 If FORCE is nonzero, then force this conversion, even if
5915 we would rather not do it. Usually set when using an explicit
5916 cast. A C-style cast is being processed iff C_CAST_P is true.
5918 Return error_mark_node, if something goes wrong. */
5921 build_ptrmemfunc (tree type
, tree pfn
, int force
, bool c_cast_p
)
5927 if (error_operand_p (pfn
))
5928 return error_mark_node
;
5930 pfn_type
= TREE_TYPE (pfn
);
5931 to_type
= build_ptrmemfunc_type (type
);
5933 /* Handle multiple conversions of pointer to member functions. */
5934 if (TYPE_PTRMEMFUNC_P (pfn_type
))
5936 tree delta
= NULL_TREE
;
5937 tree npfn
= NULL_TREE
;
5941 && !can_convert_arg (to_type
, TREE_TYPE (pfn
), pfn
, LOOKUP_NORMAL
))
5942 error ("invalid conversion to type %qT from type %qT",
5945 n
= get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type
),
5946 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type
),
5950 /* We don't have to do any conversion to convert a
5951 pointer-to-member to its own type. But, we don't want to
5952 just return a PTRMEM_CST if there's an explicit cast; that
5953 cast should make the expression an invalid template argument. */
5954 if (TREE_CODE (pfn
) != PTRMEM_CST
)
5956 if (same_type_p (to_type
, pfn_type
))
5958 else if (integer_zerop (n
))
5959 return build_reinterpret_cast (to_type
, pfn
);
5962 if (TREE_SIDE_EFFECTS (pfn
))
5963 pfn
= save_expr (pfn
);
5965 /* Obtain the function pointer and the current DELTA. */
5966 if (TREE_CODE (pfn
) == PTRMEM_CST
)
5967 expand_ptrmemfunc_cst (pfn
, &delta
, &npfn
);
5970 npfn
= build_ptrmemfunc_access_expr (pfn
, pfn_identifier
);
5971 delta
= build_ptrmemfunc_access_expr (pfn
, delta_identifier
);
5974 /* Just adjust the DELTA field. */
5975 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5976 (TREE_TYPE (delta
), ptrdiff_type_node
));
5977 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
== ptrmemfunc_vbit_in_delta
)
5978 n
= cp_build_binary_op (LSHIFT_EXPR
, n
, integer_one_node
);
5979 delta
= cp_build_binary_op (PLUS_EXPR
, delta
, n
);
5980 return build_ptrmemfunc1 (to_type
, delta
, npfn
);
5983 /* Handle null pointer to member function conversions. */
5984 if (integer_zerop (pfn
))
5986 pfn
= build_c_cast (type
, integer_zero_node
);
5987 return build_ptrmemfunc1 (to_type
,
5992 if (type_unknown_p (pfn
))
5993 return instantiate_type (type
, pfn
, tf_warning_or_error
);
5995 fn
= TREE_OPERAND (pfn
, 0);
5996 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
5997 /* In a template, we will have preserved the
5999 || (processing_template_decl
&& TREE_CODE (fn
) == OFFSET_REF
));
6000 return make_ptrmem_cst (to_type
, fn
);
6003 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6006 ??? There is no consistency as to the types returned for the above
6007 values. Some code acts as if it were a sizetype and some as if it were
6008 integer_type_node. */
6011 expand_ptrmemfunc_cst (tree cst
, tree
*delta
, tree
*pfn
)
6013 tree type
= TREE_TYPE (cst
);
6014 tree fn
= PTRMEM_CST_MEMBER (cst
);
6015 tree ptr_class
, fn_class
;
6017 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6019 /* The class that the function belongs to. */
6020 fn_class
= DECL_CONTEXT (fn
);
6022 /* The class that we're creating a pointer to member of. */
6023 ptr_class
= TYPE_PTRMEMFUNC_OBJECT_TYPE (type
);
6025 /* First, calculate the adjustment to the function's class. */
6026 *delta
= get_delta_difference (fn_class
, ptr_class
, /*force=*/0,
6029 if (!DECL_VIRTUAL_P (fn
))
6030 *pfn
= convert (TYPE_PTRMEMFUNC_FN_TYPE (type
), build_addr_func (fn
));
6033 /* If we're dealing with a virtual function, we have to adjust 'this'
6034 again, to point to the base which provides the vtable entry for
6035 fn; the call will do the opposite adjustment. */
6036 tree orig_class
= DECL_CONTEXT (fn
);
6037 tree binfo
= binfo_or_else (orig_class
, fn_class
);
6038 *delta
= build2 (PLUS_EXPR
, TREE_TYPE (*delta
),
6039 *delta
, BINFO_OFFSET (binfo
));
6040 *delta
= fold_if_not_in_template (*delta
);
6042 /* We set PFN to the vtable offset at which the function can be
6043 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6044 case delta is shifted left, and then incremented). */
6045 *pfn
= DECL_VINDEX (fn
);
6046 *pfn
= build2 (MULT_EXPR
, integer_type_node
, *pfn
,
6047 TYPE_SIZE_UNIT (vtable_entry_type
));
6048 *pfn
= fold_if_not_in_template (*pfn
);
6050 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION
)
6052 case ptrmemfunc_vbit_in_pfn
:
6053 *pfn
= build2 (PLUS_EXPR
, integer_type_node
, *pfn
,
6055 *pfn
= fold_if_not_in_template (*pfn
);
6058 case ptrmemfunc_vbit_in_delta
:
6059 *delta
= build2 (LSHIFT_EXPR
, TREE_TYPE (*delta
),
6060 *delta
, integer_one_node
);
6061 *delta
= fold_if_not_in_template (*delta
);
6062 *delta
= build2 (PLUS_EXPR
, TREE_TYPE (*delta
),
6063 *delta
, integer_one_node
);
6064 *delta
= fold_if_not_in_template (*delta
);
6071 *pfn
= build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type
), *pfn
);
6072 *pfn
= fold_if_not_in_template (*pfn
);
6076 /* Return an expression for PFN from the pointer-to-member function
6080 pfn_from_ptrmemfunc (tree t
)
6082 if (TREE_CODE (t
) == PTRMEM_CST
)
6087 expand_ptrmemfunc_cst (t
, &delta
, &pfn
);
6092 return build_ptrmemfunc_access_expr (t
, pfn_identifier
);
6095 /* Convert value RHS to type TYPE as preparation for an assignment to
6096 an lvalue of type TYPE. ERRTYPE is a string to use in error
6097 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6098 are doing the conversion in order to pass the PARMNUMth argument of
6102 convert_for_assignment (tree type
, tree rhs
,
6103 const char *errtype
, tree fndecl
, int parmnum
)
6106 enum tree_code coder
;
6108 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6109 if (TREE_CODE (rhs
) == NON_LVALUE_EXPR
)
6110 rhs
= TREE_OPERAND (rhs
, 0);
6112 rhstype
= TREE_TYPE (rhs
);
6113 coder
= TREE_CODE (rhstype
);
6115 if (TREE_CODE (type
) == VECTOR_TYPE
&& coder
== VECTOR_TYPE
6116 && vector_types_convertible_p (type
, rhstype
))
6117 return convert (type
, rhs
);
6119 if (rhs
== error_mark_node
|| rhstype
== error_mark_node
)
6120 return error_mark_node
;
6121 if (TREE_CODE (rhs
) == TREE_LIST
&& TREE_VALUE (rhs
) == error_mark_node
)
6122 return error_mark_node
;
6124 /* The RHS of an assignment cannot have void type. */
6125 if (coder
== VOID_TYPE
)
6127 error ("void value not ignored as it ought to be");
6128 return error_mark_node
;
6131 /* Simplify the RHS if possible. */
6132 if (TREE_CODE (rhs
) == CONST_DECL
)
6133 rhs
= DECL_INITIAL (rhs
);
6135 if (c_dialect_objc ())
6138 tree rname
= fndecl
;
6140 if (!strcmp (errtype
, "assignment"))
6142 else if (!strcmp (errtype
, "initialization"))
6146 tree selector
= objc_message_selector ();
6150 if (selector
&& parmno
> 1)
6157 if (objc_compare_types (type
, rhstype
, parmno
, rname
))
6158 return convert (type
, rhs
);
6163 The expression is implicitly converted (clause _conv_) to the
6164 cv-unqualified type of the left operand.
6166 We allow bad conversions here because by the time we get to this point
6167 we are committed to doing the conversion. If we end up doing a bad
6168 conversion, convert_like will complain. */
6169 if (!can_convert_arg_bad (type
, rhstype
, rhs
))
6171 /* When -Wno-pmf-conversions is use, we just silently allow
6172 conversions from pointers-to-members to plain pointers. If
6173 the conversion doesn't work, cp_convert will complain. */
6175 && TYPE_PTR_P (type
)
6176 && TYPE_PTRMEMFUNC_P (rhstype
))
6177 rhs
= cp_convert (strip_top_quals (type
), rhs
);
6180 /* If the right-hand side has unknown type, then it is an
6181 overloaded function. Call instantiate_type to get error
6183 if (rhstype
== unknown_type_node
)
6184 instantiate_type (type
, rhs
, tf_warning_or_error
);
6186 error ("cannot convert %qT to %qT for argument %qP to %qD",
6187 rhstype
, type
, parmnum
, fndecl
);
6189 error ("cannot convert %qT to %qT in %s", rhstype
, type
, errtype
);
6190 return error_mark_node
;
6193 if (warn_missing_format_attribute
)
6195 const enum tree_code codel
= TREE_CODE (type
);
6196 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
6198 && check_missing_format_attribute (type
, rhstype
))
6199 warning (OPT_Wmissing_format_attribute
,
6200 "%s might be a candidate for a format attribute",
6204 return perform_implicit_conversion (strip_top_quals (type
), rhs
);
6207 /* Convert RHS to be of type TYPE.
6208 If EXP is nonzero, it is the target of the initialization.
6209 ERRTYPE is a string to use in error messages.
6211 Two major differences between the behavior of
6212 `convert_for_assignment' and `convert_for_initialization'
6213 are that references are bashed in the former, while
6214 copied in the latter, and aggregates are assigned in
6215 the former (operator=) while initialized in the
6218 If using constructor make sure no conversion operator exists, if one does
6219 exist, an ambiguity exists.
6221 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6224 convert_for_initialization (tree exp
, tree type
, tree rhs
, int flags
,
6225 const char *errtype
, tree fndecl
, int parmnum
)
6227 enum tree_code codel
= TREE_CODE (type
);
6229 enum tree_code coder
;
6231 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6232 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6233 if (TREE_CODE (rhs
) == NOP_EXPR
6234 && TREE_TYPE (rhs
) == TREE_TYPE (TREE_OPERAND (rhs
, 0))
6235 && codel
!= REFERENCE_TYPE
)
6236 rhs
= TREE_OPERAND (rhs
, 0);
6238 if (type
== error_mark_node
6239 || rhs
== error_mark_node
6240 || (TREE_CODE (rhs
) == TREE_LIST
&& TREE_VALUE (rhs
) == error_mark_node
))
6241 return error_mark_node
;
6243 if ((TREE_CODE (TREE_TYPE (rhs
)) == ARRAY_TYPE
6244 && TREE_CODE (type
) != ARRAY_TYPE
6245 && (TREE_CODE (type
) != REFERENCE_TYPE
6246 || TREE_CODE (TREE_TYPE (type
)) != ARRAY_TYPE
))
6247 || (TREE_CODE (TREE_TYPE (rhs
)) == FUNCTION_TYPE
6248 && (TREE_CODE (type
) != REFERENCE_TYPE
6249 || TREE_CODE (TREE_TYPE (type
)) != FUNCTION_TYPE
))
6250 || TREE_CODE (TREE_TYPE (rhs
)) == METHOD_TYPE
)
6251 rhs
= decay_conversion (rhs
);
6253 rhstype
= TREE_TYPE (rhs
);
6254 coder
= TREE_CODE (rhstype
);
6256 if (coder
== ERROR_MARK
)
6257 return error_mark_node
;
6259 /* We accept references to incomplete types, so we can
6260 return here before checking if RHS is of complete type. */
6262 if (codel
== REFERENCE_TYPE
)
6264 /* This should eventually happen in convert_arguments. */
6265 int savew
= 0, savee
= 0;
6268 savew
= warningcount
, savee
= errorcount
;
6269 rhs
= initialize_reference (type
, rhs
, /*decl=*/NULL_TREE
,
6273 if (warningcount
> savew
)
6274 warning (0, "in passing argument %P of %q+D", parmnum
, fndecl
);
6275 else if (errorcount
> savee
)
6276 error ("in passing argument %P of %q+D", parmnum
, fndecl
);
6282 exp
= require_complete_type (exp
);
6283 if (exp
== error_mark_node
)
6284 return error_mark_node
;
6286 rhstype
= non_reference (rhstype
);
6288 type
= complete_type (type
);
6290 if (IS_AGGR_TYPE (type
))
6291 return ocp_convert (type
, rhs
, CONV_IMPLICIT
|CONV_FORCE_TEMP
, flags
);
6293 return convert_for_assignment (type
, rhs
, errtype
, fndecl
, parmnum
);
6296 /* If RETVAL is the address of, or a reference to, a local variable or
6297 temporary give an appropriate warning. */
6300 maybe_warn_about_returning_address_of_local (tree retval
)
6302 tree valtype
= TREE_TYPE (DECL_RESULT (current_function_decl
));
6303 tree whats_returned
= retval
;
6307 if (TREE_CODE (whats_returned
) == COMPOUND_EXPR
)
6308 whats_returned
= TREE_OPERAND (whats_returned
, 1);
6309 else if (TREE_CODE (whats_returned
) == CONVERT_EXPR
6310 || TREE_CODE (whats_returned
) == NON_LVALUE_EXPR
6311 || TREE_CODE (whats_returned
) == NOP_EXPR
)
6312 whats_returned
= TREE_OPERAND (whats_returned
, 0);
6317 if (TREE_CODE (whats_returned
) != ADDR_EXPR
)
6319 whats_returned
= TREE_OPERAND (whats_returned
, 0);
6321 if (TREE_CODE (valtype
) == REFERENCE_TYPE
)
6323 if (TREE_CODE (whats_returned
) == AGGR_INIT_EXPR
6324 || TREE_CODE (whats_returned
) == TARGET_EXPR
)
6326 warning (0, "returning reference to temporary");
6329 if (TREE_CODE (whats_returned
) == VAR_DECL
6330 && DECL_NAME (whats_returned
)
6331 && TEMP_NAME_P (DECL_NAME (whats_returned
)))
6333 warning (0, "reference to non-lvalue returned");
6338 if (DECL_P (whats_returned
)
6339 && DECL_NAME (whats_returned
)
6340 && DECL_FUNCTION_SCOPE_P (whats_returned
)
6341 && !(TREE_STATIC (whats_returned
)
6342 || TREE_PUBLIC (whats_returned
)))
6344 if (TREE_CODE (valtype
) == REFERENCE_TYPE
)
6345 warning (0, "reference to local variable %q+D returned",
6348 warning (0, "address of local variable %q+D returned",
6354 /* Check that returning RETVAL from the current function is valid.
6355 Return an expression explicitly showing all conversions required to
6356 change RETVAL into the function return type, and to assign it to
6357 the DECL_RESULT for the function. Set *NO_WARNING to true if
6358 code reaches end of non-void function warning shouldn't be issued
6359 on this RETURN_EXPR. */
6362 check_return_expr (tree retval
, bool *no_warning
)
6365 /* The type actually returned by the function, after any
6368 int fn_returns_value_p
;
6370 *no_warning
= false;
6372 /* A `volatile' function is one that isn't supposed to return, ever.
6373 (This is a G++ extension, used to get better code for functions
6374 that call the `volatile' function.) */
6375 if (TREE_THIS_VOLATILE (current_function_decl
))
6376 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6378 /* Check for various simple errors. */
6379 if (DECL_DESTRUCTOR_P (current_function_decl
))
6382 error ("returning a value from a destructor");
6385 else if (DECL_CONSTRUCTOR_P (current_function_decl
))
6387 if (in_function_try_handler
)
6388 /* If a return statement appears in a handler of the
6389 function-try-block of a constructor, the program is ill-formed. */
6390 error ("cannot return from a handler of a function-try-block of a constructor");
6392 /* You can't return a value from a constructor. */
6393 error ("returning a value from a constructor");
6397 if (processing_template_decl
)
6399 current_function_returns_value
= 1;
6403 /* When no explicit return-value is given in a function with a named
6404 return value, the named return value is used. */
6405 result
= DECL_RESULT (current_function_decl
);
6406 valtype
= TREE_TYPE (result
);
6407 gcc_assert (valtype
!= NULL_TREE
);
6408 fn_returns_value_p
= !VOID_TYPE_P (valtype
);
6409 if (!retval
&& DECL_NAME (result
) && fn_returns_value_p
)
6412 /* Check for a return statement with no return value in a function
6413 that's supposed to return a value. */
6414 if (!retval
&& fn_returns_value_p
)
6416 pedwarn ("return-statement with no value, in function returning %qT",
6418 /* Clear this, so finish_function won't say that we reach the
6419 end of a non-void function (which we don't, we gave a
6421 current_function_returns_null
= 0;
6422 /* And signal caller that TREE_NO_WARNING should be set on the
6423 RETURN_EXPR to avoid control reaches end of non-void function
6424 warnings in tree-cfg.c. */
6427 /* Check for a return statement with a value in a function that
6428 isn't supposed to return a value. */
6429 else if (retval
&& !fn_returns_value_p
)
6431 if (VOID_TYPE_P (TREE_TYPE (retval
)))
6432 /* You can return a `void' value from a function of `void'
6433 type. In that case, we have to evaluate the expression for
6434 its side-effects. */
6435 finish_expr_stmt (retval
);
6437 pedwarn ("return-statement with a value, in function "
6438 "returning 'void'");
6440 current_function_returns_null
= 1;
6442 /* There's really no value to return, after all. */
6446 /* Remember that this function can sometimes return without a
6448 current_function_returns_null
= 1;
6450 /* Remember that this function did return a value. */
6451 current_function_returns_value
= 1;
6453 /* Check for erroneous operands -- but after giving ourselves a
6454 chance to provide an error about returning a value from a void
6456 if (error_operand_p (retval
))
6458 current_function_return_value
= error_mark_node
;
6459 return error_mark_node
;
6462 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
6463 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl
) == NEW_EXPR
6464 || DECL_OVERLOADED_OPERATOR_P (current_function_decl
) == VEC_NEW_EXPR
)
6465 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl
))
6467 && null_ptr_cst_p (retval
))
6468 warning (0, "%<operator new%> must not return NULL unless it is "
6469 "declared %<throw()%> (or -fcheck-new is in effect)");
6471 /* Effective C++ rule 15. See also start_function. */
6473 && DECL_NAME (current_function_decl
) == ansi_assopname(NOP_EXPR
))
6477 /* The function return type must be a reference to the current
6479 if (TREE_CODE (valtype
) == REFERENCE_TYPE
6480 && same_type_ignoring_top_level_qualifiers_p
6481 (TREE_TYPE (valtype
), TREE_TYPE (current_class_ref
)))
6483 /* Returning '*this' is obviously OK. */
6484 if (retval
== current_class_ref
)
6486 /* If we are calling a function whose return type is the same of
6487 the current class reference, it is ok. */
6488 else if (TREE_CODE (retval
) == INDIRECT_REF
6489 && TREE_CODE (TREE_OPERAND (retval
, 0)) == CALL_EXPR
)
6494 warning (OPT_Weffc__
, "%<operator=%> should return a reference to %<*this%>");
6497 /* The fabled Named Return Value optimization, as per [class.copy]/15:
6499 [...] For a function with a class return type, if the expression
6500 in the return statement is the name of a local object, and the cv-
6501 unqualified type of the local object is the same as the function
6502 return type, an implementation is permitted to omit creating the tem-
6503 porary object to hold the function return value [...]
6505 So, if this is a value-returning function that always returns the same
6506 local variable, remember it.
6508 It might be nice to be more flexible, and choose the first suitable
6509 variable even if the function sometimes returns something else, but
6510 then we run the risk of clobbering the variable we chose if the other
6511 returned expression uses the chosen variable somehow. And people expect
6512 this restriction, anyway. (jason 2000-11-19)
6514 See finish_function and finalize_nrv for the rest of this optimization. */
6516 if (fn_returns_value_p
&& flag_elide_constructors
)
6518 if (retval
!= NULL_TREE
6519 && (current_function_return_value
== NULL_TREE
6520 || current_function_return_value
== retval
)
6521 && TREE_CODE (retval
) == VAR_DECL
6522 && DECL_CONTEXT (retval
) == current_function_decl
6523 && ! TREE_STATIC (retval
)
6524 && (DECL_ALIGN (retval
)
6525 >= DECL_ALIGN (DECL_RESULT (current_function_decl
)))
6526 && same_type_p ((TYPE_MAIN_VARIANT
6527 (TREE_TYPE (retval
))),
6529 (TREE_TYPE (TREE_TYPE (current_function_decl
))))))
6530 current_function_return_value
= retval
;
6532 current_function_return_value
= error_mark_node
;
6535 /* We don't need to do any conversions when there's nothing being
6540 /* Do any required conversions. */
6541 if (retval
== result
|| DECL_CONSTRUCTOR_P (current_function_decl
))
6542 /* No conversions are required. */
6546 /* The type the function is declared to return. */
6547 tree functype
= TREE_TYPE (TREE_TYPE (current_function_decl
));
6549 /* The functype's return type will have been set to void, if it
6550 was an incomplete type. Just treat this as 'return;' */
6551 if (VOID_TYPE_P (functype
))
6552 return error_mark_node
;
6554 /* First convert the value to the function's return type, then
6555 to the type of return value's location to handle the
6556 case that functype is smaller than the valtype. */
6557 retval
= convert_for_initialization
6558 (NULL_TREE
, functype
, retval
, LOOKUP_NORMAL
|LOOKUP_ONLYCONVERTING
,
6559 "return", NULL_TREE
, 0);
6560 retval
= convert (valtype
, retval
);
6562 /* If the conversion failed, treat this just like `return;'. */
6563 if (retval
== error_mark_node
)
6565 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6566 else if (! current_function_returns_struct
6567 && TREE_CODE (retval
) == TARGET_EXPR
6568 && TREE_CODE (TREE_OPERAND (retval
, 1)) == AGGR_INIT_EXPR
)
6569 retval
= build2 (COMPOUND_EXPR
, TREE_TYPE (retval
), retval
,
6570 TREE_OPERAND (retval
, 0));
6572 maybe_warn_about_returning_address_of_local (retval
);
6575 /* Actually copy the value returned into the appropriate location. */
6576 if (retval
&& retval
!= result
)
6577 retval
= build2 (INIT_EXPR
, TREE_TYPE (result
), result
, retval
);
6583 /* Returns nonzero if the pointer-type FROM can be converted to the
6584 pointer-type TO via a qualification conversion. If CONSTP is -1,
6585 then we return nonzero if the pointers are similar, and the
6586 cv-qualification signature of FROM is a proper subset of that of TO.
6588 If CONSTP is positive, then all outer pointers have been
6592 comp_ptr_ttypes_real (tree to
, tree from
, int constp
)
6594 bool to_more_cv_qualified
= false;
6596 for (; ; to
= TREE_TYPE (to
), from
= TREE_TYPE (from
))
6598 if (TREE_CODE (to
) != TREE_CODE (from
))
6601 if (TREE_CODE (from
) == OFFSET_TYPE
6602 && !same_type_p (TYPE_OFFSET_BASETYPE (from
),
6603 TYPE_OFFSET_BASETYPE (to
)))
6606 /* Const and volatile mean something different for function types,
6607 so the usual checks are not appropriate. */
6608 if (TREE_CODE (to
) != FUNCTION_TYPE
&& TREE_CODE (to
) != METHOD_TYPE
)
6610 /* In Objective-C++, some types may have been 'volatilized' by
6611 the compiler for EH; when comparing them here, the volatile
6612 qualification must be ignored. */
6613 bool objc_quals_match
= objc_type_quals_match (to
, from
);
6615 if (!at_least_as_qualified_p (to
, from
) && !objc_quals_match
)
6618 if (!at_least_as_qualified_p (from
, to
) && !objc_quals_match
)
6622 to_more_cv_qualified
= true;
6626 constp
&= TYPE_READONLY (to
);
6629 if (TREE_CODE (to
) != POINTER_TYPE
&& !TYPE_PTRMEM_P (to
))
6630 return ((constp
>= 0 || to_more_cv_qualified
)
6631 && same_type_ignoring_top_level_qualifiers_p (to
, from
));
6635 /* When comparing, say, char ** to char const **, this function takes
6636 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6637 types to this function. */
6640 comp_ptr_ttypes (tree to
, tree from
)
6642 return comp_ptr_ttypes_real (to
, from
, 1);
6645 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6646 type or inheritance-related types, regardless of cv-quals. */
6649 ptr_reasonably_similar (tree to
, tree from
)
6651 for (; ; to
= TREE_TYPE (to
), from
= TREE_TYPE (from
))
6653 /* Any target type is similar enough to void. */
6654 if (TREE_CODE (to
) == VOID_TYPE
6655 || TREE_CODE (from
) == VOID_TYPE
)
6658 if (TREE_CODE (to
) != TREE_CODE (from
))
6661 if (TREE_CODE (from
) == OFFSET_TYPE
6662 && comptypes (TYPE_OFFSET_BASETYPE (to
),
6663 TYPE_OFFSET_BASETYPE (from
),
6664 COMPARE_BASE
| COMPARE_DERIVED
))
6667 if (TREE_CODE (to
) == VECTOR_TYPE
6668 && vector_types_convertible_p (to
, from
))
6671 if (TREE_CODE (to
) == INTEGER_TYPE
6672 && TYPE_PRECISION (to
) == TYPE_PRECISION (from
))
6675 if (TREE_CODE (to
) == FUNCTION_TYPE
)
6678 if (TREE_CODE (to
) != POINTER_TYPE
)
6680 (TYPE_MAIN_VARIANT (to
), TYPE_MAIN_VARIANT (from
),
6681 COMPARE_BASE
| COMPARE_DERIVED
);
6685 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
6686 pointer-to-member types) are the same, ignoring cv-qualification at
6690 comp_ptr_ttypes_const (tree to
, tree from
)
6692 for (; ; to
= TREE_TYPE (to
), from
= TREE_TYPE (from
))
6694 if (TREE_CODE (to
) != TREE_CODE (from
))
6697 if (TREE_CODE (from
) == OFFSET_TYPE
6698 && same_type_p (TYPE_OFFSET_BASETYPE (from
),
6699 TYPE_OFFSET_BASETYPE (to
)))
6702 if (TREE_CODE (to
) != POINTER_TYPE
)
6703 return same_type_ignoring_top_level_qualifiers_p (to
, from
);
6707 /* Returns the type qualifiers for this type, including the qualifiers on the
6708 elements for an array type. */
6711 cp_type_quals (tree type
)
6713 type
= strip_array_types (type
);
6714 if (type
== error_mark_node
)
6715 return TYPE_UNQUALIFIED
;
6716 return TYPE_QUALS (type
);
6719 /* Returns nonzero if the TYPE contains a mutable member. */
6722 cp_has_mutable_p (tree type
)
6724 type
= strip_array_types (type
);
6726 return CLASS_TYPE_P (type
) && CLASSTYPE_HAS_MUTABLE (type
);
6729 /* Apply the TYPE_QUALS to the new DECL. */
6731 cp_apply_type_quals_to_decl (int type_quals
, tree decl
)
6733 tree type
= TREE_TYPE (decl
);
6735 if (type
== error_mark_node
)
6738 if (TREE_CODE (type
) == FUNCTION_TYPE
6739 && type_quals
!= TYPE_UNQUALIFIED
)
6741 /* This was an error in C++98 (cv-qualifiers cannot be added to
6742 a function type), but DR 295 makes the code well-formed by
6743 dropping the extra qualifiers. */
6746 tree bad_type
= build_qualified_type (type
, type_quals
);
6747 pedwarn ("ignoring %qV qualifiers added to function type %qT",
6751 TREE_TYPE (decl
) = TYPE_MAIN_VARIANT (type
);
6755 /* Avoid setting TREE_READONLY incorrectly. */
6756 if (/* If the object has a constructor, the constructor may modify
6758 TYPE_NEEDS_CONSTRUCTING (type
)
6759 /* If the type isn't complete, we don't know yet if it will need
6761 || !COMPLETE_TYPE_P (type
)
6762 /* If the type has a mutable component, that component might be
6764 || TYPE_HAS_MUTABLE_P (type
))
6765 type_quals
&= ~TYPE_QUAL_CONST
;
6767 c_apply_type_quals_to_decl (type_quals
, decl
);
6770 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6771 exemplar types such that casting T1 to T2 is casting away constness
6772 if and only if there is no implicit conversion from T1 to T2. */
6775 casts_away_constness_r (tree
*t1
, tree
*t2
)
6780 /* [expr.const.cast]
6782 For multi-level pointer to members and multi-level mixed pointers
6783 and pointers to members (conv.qual), the "member" aspect of a
6784 pointer to member level is ignored when determining if a const
6785 cv-qualifier has been cast away. */
6786 /* [expr.const.cast]
6788 For two pointer types:
6790 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6791 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6794 casting from X1 to X2 casts away constness if, for a non-pointer
6795 type T there does not exist an implicit conversion (clause
6798 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6802 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6803 if ((!TYPE_PTR_P (*t1
) && !TYPE_PTRMEM_P (*t1
))
6804 || (!TYPE_PTR_P (*t2
) && !TYPE_PTRMEM_P (*t2
)))
6806 *t1
= cp_build_qualified_type (void_type_node
,
6807 cp_type_quals (*t1
));
6808 *t2
= cp_build_qualified_type (void_type_node
,
6809 cp_type_quals (*t2
));
6813 quals1
= cp_type_quals (*t1
);
6814 quals2
= cp_type_quals (*t2
);
6816 if (TYPE_PTRMEM_P (*t1
))
6817 *t1
= TYPE_PTRMEM_POINTED_TO_TYPE (*t1
);
6819 *t1
= TREE_TYPE (*t1
);
6820 if (TYPE_PTRMEM_P (*t2
))
6821 *t2
= TYPE_PTRMEM_POINTED_TO_TYPE (*t2
);
6823 *t2
= TREE_TYPE (*t2
);
6825 casts_away_constness_r (t1
, t2
);
6826 *t1
= build_pointer_type (*t1
);
6827 *t2
= build_pointer_type (*t2
);
6828 *t1
= cp_build_qualified_type (*t1
, quals1
);
6829 *t2
= cp_build_qualified_type (*t2
, quals2
);
6832 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6836 casts_away_constness (tree t1
, tree t2
)
6838 if (TREE_CODE (t2
) == REFERENCE_TYPE
)
6840 /* [expr.const.cast]
6842 Casting from an lvalue of type T1 to an lvalue of type T2
6843 using a reference cast casts away constness if a cast from an
6844 rvalue of type "pointer to T1" to the type "pointer to T2"
6845 casts away constness. */
6846 t1
= (TREE_CODE (t1
) == REFERENCE_TYPE
? TREE_TYPE (t1
) : t1
);
6847 return casts_away_constness (build_pointer_type (t1
),
6848 build_pointer_type (TREE_TYPE (t2
)));
6851 if (TYPE_PTRMEM_P (t1
) && TYPE_PTRMEM_P (t2
))
6852 /* [expr.const.cast]
6854 Casting from an rvalue of type "pointer to data member of X
6855 of type T1" to the type "pointer to data member of Y of type
6856 T2" casts away constness if a cast from an rvalue of type
6857 "pointer to T1" to the type "pointer to T2" casts away
6859 return casts_away_constness
6860 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1
)),
6861 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2
)));
6863 /* Casting away constness is only something that makes sense for
6864 pointer or reference types. */
6865 if (TREE_CODE (t1
) != POINTER_TYPE
6866 || TREE_CODE (t2
) != POINTER_TYPE
)
6869 /* Top-level qualifiers don't matter. */
6870 t1
= TYPE_MAIN_VARIANT (t1
);
6871 t2
= TYPE_MAIN_VARIANT (t2
);
6872 casts_away_constness_r (&t1
, &t2
);
6873 if (!can_convert (t2
, t1
))
6879 /* If T is a REFERENCE_TYPE return the type to which T refers.
6880 Otherwise, return T itself. */
6883 non_reference (tree t
)
6885 if (TREE_CODE (t
) == REFERENCE_TYPE
)
6891 /* Return nonzero if REF is an lvalue valid for this language;
6892 otherwise, print an error message and return zero. USE says
6893 how the lvalue is being used and so selects the error message. */
6896 lvalue_or_else (tree ref
, enum lvalue_use use
)
6898 int win
= lvalue_p (ref
);