1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 88, 91-6, 1997 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* This file is part of the C front end.
23 It contains routines to build C expressions given their operands,
24 including computing the types of the result, C-specific error checks,
25 and some optimization.
27 There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
28 and to process initializations in declarations (since they work
29 like a strange sort of assignment). */
38 /* Nonzero if we've already printed a "missing braces around initializer"
39 message within this initializer. */
40 static int missing_braces_mentioned;
42 extern char *index ();
43 extern char *rindex ();
45 static tree qualify_type PROTO((tree, tree));
46 static int comp_target_types PROTO((tree, tree));
47 static int function_types_compatible_p PROTO((tree, tree));
48 static int type_lists_compatible_p PROTO((tree, tree));
49 static int self_promoting_type_p PROTO((tree));
50 static tree decl_constant_value PROTO((tree));
51 static tree lookup_field PROTO((tree, tree, tree *));
52 static tree convert_arguments PROTO((tree, tree, tree, tree));
53 static tree pointer_int_sum PROTO((enum tree_code, tree, tree));
54 static tree pointer_diff PROTO((tree, tree));
55 static tree unary_complex_lvalue PROTO((enum tree_code, tree));
56 static void pedantic_lvalue_warning PROTO((enum tree_code));
57 static tree internal_build_compound_expr PROTO((tree, int));
58 static tree convert_for_assignment PROTO((tree, tree, char *, tree,
60 static void warn_for_assignment PROTO((char *, char *, tree, int));
61 static tree valid_compound_expr_initializer PROTO((tree, tree));
62 static void push_string PROTO((char *));
63 static void push_member_name PROTO((tree));
64 static void push_array_bounds PROTO((int));
65 static int spelling_length PROTO((void));
66 static char *print_spelling PROTO((char *));
67 static char *get_spelling PROTO((char *));
68 static void warning_init PROTO((char *, char *,
70 static tree digest_init PROTO((tree, tree, int, int));
71 static void check_init_type_bitfields PROTO((tree));
72 static void output_init_element PROTO((tree, tree, tree, int));
73 static void output_pending_init_elements PROTO((int));
75 /* Do `exp = require_complete_type (exp);' to make sure exp
76 does not have an incomplete type. (That includes void types.) */
79 require_complete_type (value)
82 tree type = TREE_TYPE (value);
84 /* First, detect a valid value with a complete type. */
85 if (TYPE_SIZE (type) != 0
86 && type != void_type_node)
89 incomplete_type_error (value, type);
90 return error_mark_node;
93 /* Print an error message for invalid use of an incomplete type.
94 VALUE is the expression that was used (or 0 if that isn't known)
95 and TYPE is the type that was invalid. */
98 incomplete_type_error (value, type)
104 /* Avoid duplicate error message. */
105 if (TREE_CODE (type) == ERROR_MARK)
108 if (value != 0 && (TREE_CODE (value) == VAR_DECL
109 || TREE_CODE (value) == PARM_DECL))
110 error ("`%s' has an incomplete type",
111 IDENTIFIER_POINTER (DECL_NAME (value)));
115 /* We must print an error message. Be clever about what it says. */
117 switch (TREE_CODE (type))
120 errmsg = "invalid use of undefined type `struct %s'";
124 errmsg = "invalid use of undefined type `union %s'";
128 errmsg = "invalid use of undefined type `enum %s'";
132 error ("invalid use of void expression");
136 if (TYPE_DOMAIN (type))
138 type = TREE_TYPE (type);
141 error ("invalid use of array with unspecified bounds");
148 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
149 error (errmsg, IDENTIFIER_POINTER (TYPE_NAME (type)));
151 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
152 error ("invalid use of incomplete typedef `%s'",
153 IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
157 /* Return a variant of TYPE which has all the type qualifiers of LIKE
158 as well as those of TYPE. */
161 qualify_type (type, like)
164 int constflag = TYPE_READONLY (type) || TYPE_READONLY (like);
165 int volflag = TYPE_VOLATILE (type) || TYPE_VOLATILE (like);
166 return c_build_type_variant (type, constflag, volflag);
169 /* Return the common type of two types.
170 We assume that comptypes has already been done and returned 1;
171 if that isn't so, this may crash. In particular, we assume that qualifiers
174 This is the type for the result of most arithmetic operations
175 if the operands have the given two types. */
181 register enum tree_code code1;
182 register enum tree_code code2;
185 /* Save time if the two types are the same. */
187 if (t1 == t2) return t1;
189 /* If one type is nonsense, use the other. */
190 if (t1 == error_mark_node)
192 if (t2 == error_mark_node)
195 /* Merge the attributes */
196 attributes = merge_attributes (TYPE_ATTRIBUTES (t1), TYPE_ATTRIBUTES (t2));
198 /* Treat an enum type as the unsigned integer type of the same width. */
200 if (TREE_CODE (t1) == ENUMERAL_TYPE)
201 t1 = type_for_size (TYPE_PRECISION (t1), 1);
202 if (TREE_CODE (t2) == ENUMERAL_TYPE)
203 t2 = type_for_size (TYPE_PRECISION (t2), 1);
205 code1 = TREE_CODE (t1);
206 code2 = TREE_CODE (t2);
208 /* If one type is complex, form the common type of the non-complex
209 components, then make that complex. Use T1 or T2 if it is the
211 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
213 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
214 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
215 tree subtype = common_type (subtype1, subtype2);
217 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
218 return build_type_attribute_variant (t1, attributes);
219 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
220 return build_type_attribute_variant (t2, attributes);
222 return build_type_attribute_variant (build_complex_type (subtype),
230 /* If only one is real, use it as the result. */
232 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
233 return build_type_attribute_variant (t1, attributes);
235 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
236 return build_type_attribute_variant (t2, attributes);
238 /* Both real or both integers; use the one with greater precision. */
240 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
241 return build_type_attribute_variant (t1, attributes);
242 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
243 return build_type_attribute_variant (t2, attributes);
245 /* Same precision. Prefer longs to ints even when same size. */
247 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
248 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
249 return build_type_attribute_variant (long_unsigned_type_node,
252 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
253 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
255 /* But preserve unsignedness from the other type,
256 since long cannot hold all the values of an unsigned int. */
257 if (TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
258 t1 = long_unsigned_type_node;
260 t1 = long_integer_type_node;
261 return build_type_attribute_variant (t1, attributes);
264 /* Likewise, prefer long double to double even if same size. */
265 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
266 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
267 return build_type_attribute_variant (long_double_type_node,
270 /* Otherwise prefer the unsigned one. */
272 if (TREE_UNSIGNED (t1))
273 return build_type_attribute_variant (t1, attributes);
275 return build_type_attribute_variant (t2, attributes);
278 /* For two pointers, do this recursively on the target type,
279 and combine the qualifiers of the two types' targets. */
280 /* This code was turned off; I don't know why.
281 But ANSI C specifies doing this with the qualifiers.
282 So I turned it on again. */
284 tree target = common_type (TYPE_MAIN_VARIANT (TREE_TYPE (t1)),
285 TYPE_MAIN_VARIANT (TREE_TYPE (t2)));
287 = TYPE_READONLY (TREE_TYPE (t1)) || TYPE_READONLY (TREE_TYPE (t2));
289 = TYPE_VOLATILE (TREE_TYPE (t1)) || TYPE_VOLATILE (TREE_TYPE (t2));
290 t1 = build_pointer_type (c_build_type_variant (target, constp,
292 return build_type_attribute_variant (t1, attributes);
295 t1 = build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2)));
296 return build_type_attribute_variant (t1, attributes);
301 tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
302 /* Save space: see if the result is identical to one of the args. */
303 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
304 return build_type_attribute_variant (t1, attributes);
305 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
306 return build_type_attribute_variant (t2, attributes);
307 /* Merge the element types, and have a size if either arg has one. */
308 t1 = build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
309 return build_type_attribute_variant (t1, attributes);
313 /* Function types: prefer the one that specified arg types.
314 If both do, merge the arg types. Also merge the return types. */
316 tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
317 tree p1 = TYPE_ARG_TYPES (t1);
318 tree p2 = TYPE_ARG_TYPES (t2);
323 /* Save space: see if the result is identical to one of the args. */
324 if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2))
325 return build_type_attribute_variant (t1, attributes);
326 if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1))
327 return build_type_attribute_variant (t2, attributes);
329 /* Simple way if one arg fails to specify argument types. */
330 if (TYPE_ARG_TYPES (t1) == 0)
332 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
333 return build_type_attribute_variant (t1, attributes);
335 if (TYPE_ARG_TYPES (t2) == 0)
337 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
338 return build_type_attribute_variant (t1, attributes);
341 /* If both args specify argument types, we must merge the two
342 lists, argument by argument. */
344 len = list_length (p1);
347 for (i = 0; i < len; i++)
348 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
353 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
355 /* A null type means arg type is not specified.
356 Take whatever the other function type has. */
357 if (TREE_VALUE (p1) == 0)
359 TREE_VALUE (n) = TREE_VALUE (p2);
362 if (TREE_VALUE (p2) == 0)
364 TREE_VALUE (n) = TREE_VALUE (p1);
368 /* Given wait (union {union wait *u; int *i} *)
369 and wait (union wait *),
370 prefer union wait * as type of parm. */
371 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
372 && TREE_VALUE (p1) != TREE_VALUE (p2))
375 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
376 memb; memb = TREE_CHAIN (memb))
377 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2)))
379 TREE_VALUE (n) = TREE_VALUE (p2);
381 pedwarn ("function types not truly compatible in ANSI C");
385 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
386 && TREE_VALUE (p2) != TREE_VALUE (p1))
389 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
390 memb; memb = TREE_CHAIN (memb))
391 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1)))
393 TREE_VALUE (n) = TREE_VALUE (p1);
395 pedwarn ("function types not truly compatible in ANSI C");
399 TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2));
403 t1 = build_function_type (valtype, newargs);
404 /* ... falls through ... */
408 return build_type_attribute_variant (t1, attributes);
413 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
414 or various other operations. Return 2 if they are compatible
415 but a warning may be needed if you use them together. */
418 comptypes (type1, type2)
421 register tree t1 = type1;
422 register tree t2 = type2;
425 /* Suppress errors caused by previously reported errors. */
427 if (t1 == t2 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
430 /* Treat an enum type as the integer type of the same width and
433 if (TREE_CODE (t1) == ENUMERAL_TYPE)
434 t1 = type_for_size (TYPE_PRECISION (t1), TREE_UNSIGNED (t1));
435 if (TREE_CODE (t2) == ENUMERAL_TYPE)
436 t2 = type_for_size (TYPE_PRECISION (t2), TREE_UNSIGNED (t2));
441 /* Different classes of types can't be compatible. */
443 if (TREE_CODE (t1) != TREE_CODE (t2)) return 0;
445 /* Qualifiers must match. */
447 if (TYPE_READONLY (t1) != TYPE_READONLY (t2))
449 if (TYPE_VOLATILE (t1) != TYPE_VOLATILE (t2))
452 /* Allow for two different type nodes which have essentially the same
453 definition. Note that we already checked for equality of the type
454 type qualifiers (just above). */
456 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
459 #ifndef COMP_TYPE_ATTRIBUTES
460 #define COMP_TYPE_ATTRIBUTES(t1,t2) 1
463 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
464 if (! (attrval = COMP_TYPE_ATTRIBUTES (t1, t2)))
467 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
470 switch (TREE_CODE (t1))
473 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
474 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
478 val = function_types_compatible_p (t1, t2);
483 tree d1 = TYPE_DOMAIN (t1);
484 tree d2 = TYPE_DOMAIN (t2);
487 /* Target types must match incl. qualifiers. */
488 if (TREE_TYPE (t1) != TREE_TYPE (t2)
489 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
492 /* Sizes must match unless one is missing or variable. */
493 if (d1 == 0 || d2 == 0 || d1 == d2
494 || TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
495 || TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
496 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST
497 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)
500 if (! ((TREE_INT_CST_LOW (TYPE_MIN_VALUE (d1))
501 == TREE_INT_CST_LOW (TYPE_MIN_VALUE (d2)))
502 && (TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d1))
503 == TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d2)))
504 && (TREE_INT_CST_LOW (TYPE_MAX_VALUE (d1))
505 == TREE_INT_CST_LOW (TYPE_MAX_VALUE (d2)))
506 && (TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d1))
507 == TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d2)))))
513 if (maybe_objc_comptypes (t1, t2, 0) == 1)
520 return attrval == 2 && val == 1 ? 2 : val;
523 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
524 ignoring their qualifiers. */
527 comp_target_types (ttl, ttr)
532 /* Give maybe_objc_comptypes a crack at letting these types through. */
533 if (val = maybe_objc_comptypes (ttl, ttr, 1) >= 0)
536 val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)),
537 TYPE_MAIN_VARIANT (TREE_TYPE (ttr)));
539 if (val == 2 && pedantic)
540 pedwarn ("types are not quite compatible");
544 /* Subroutines of `comptypes'. */
546 /* Return 1 if two function types F1 and F2 are compatible.
547 If either type specifies no argument types,
548 the other must specify a fixed number of self-promoting arg types.
549 Otherwise, if one type specifies only the number of arguments,
550 the other must specify that number of self-promoting arg types.
551 Otherwise, the argument types must match. */
554 function_types_compatible_p (f1, f2)
558 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
562 if (!(TREE_TYPE (f1) == TREE_TYPE (f2)
563 || (val = comptypes (TREE_TYPE (f1), TREE_TYPE (f2)))))
566 args1 = TYPE_ARG_TYPES (f1);
567 args2 = TYPE_ARG_TYPES (f2);
569 /* An unspecified parmlist matches any specified parmlist
570 whose argument types don't need default promotions. */
574 if (!self_promoting_args_p (args2))
576 /* If one of these types comes from a non-prototype fn definition,
577 compare that with the other type's arglist.
578 If they don't match, ask for a warning (but no error). */
579 if (TYPE_ACTUAL_ARG_TYPES (f1)
580 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
586 if (!self_promoting_args_p (args1))
588 if (TYPE_ACTUAL_ARG_TYPES (f2)
589 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
594 /* Both types have argument lists: compare them and propagate results. */
595 val1 = type_lists_compatible_p (args1, args2);
596 return val1 != 1 ? val1 : val;
599 /* Check two lists of types for compatibility,
600 returning 0 for incompatible, 1 for compatible,
601 or 2 for compatible with warning. */
604 type_lists_compatible_p (args1, args2)
607 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
613 if (args1 == 0 && args2 == 0)
615 /* If one list is shorter than the other,
616 they fail to match. */
617 if (args1 == 0 || args2 == 0)
619 /* A null pointer instead of a type
620 means there is supposed to be an argument
621 but nothing is specified about what type it has.
622 So match anything that self-promotes. */
623 if (TREE_VALUE (args1) == 0)
625 if (! self_promoting_type_p (TREE_VALUE (args2)))
628 else if (TREE_VALUE (args2) == 0)
630 if (! self_promoting_type_p (TREE_VALUE (args1)))
633 else if (! (newval = comptypes (TREE_VALUE (args1), TREE_VALUE (args2))))
635 /* Allow wait (union {union wait *u; int *i} *)
636 and wait (union wait *) to be compatible. */
637 if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE
638 && (TYPE_NAME (TREE_VALUE (args1)) == 0
639 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args1)))
640 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST
641 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)),
642 TYPE_SIZE (TREE_VALUE (args2))))
645 for (memb = TYPE_FIELDS (TREE_VALUE (args1));
646 memb; memb = TREE_CHAIN (memb))
647 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2)))
652 else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE
653 && (TYPE_NAME (TREE_VALUE (args2)) == 0
654 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args2)))
655 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST
656 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)),
657 TYPE_SIZE (TREE_VALUE (args1))))
660 for (memb = TYPE_FIELDS (TREE_VALUE (args2));
661 memb; memb = TREE_CHAIN (memb))
662 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1)))
671 /* comptypes said ok, but record if it said to warn. */
675 args1 = TREE_CHAIN (args1);
676 args2 = TREE_CHAIN (args2);
680 /* Return 1 if PARMS specifies a fixed number of parameters
681 and none of their types is affected by default promotions. */
684 self_promoting_args_p (parms)
688 for (t = parms; t; t = TREE_CHAIN (t))
690 register tree type = TREE_VALUE (t);
692 if (TREE_CHAIN (t) == 0 && type != void_type_node)
698 if (TYPE_MAIN_VARIANT (type) == float_type_node)
701 if (C_PROMOTING_INTEGER_TYPE_P (type))
707 /* Return 1 if TYPE is not affected by default promotions. */
710 self_promoting_type_p (type)
713 if (TYPE_MAIN_VARIANT (type) == float_type_node)
716 if (C_PROMOTING_INTEGER_TYPE_P (type))
722 /* Return an unsigned type the same as TYPE in other respects. */
728 tree type1 = TYPE_MAIN_VARIANT (type);
729 if (type1 == signed_char_type_node || type1 == char_type_node)
730 return unsigned_char_type_node;
731 if (type1 == integer_type_node)
732 return unsigned_type_node;
733 if (type1 == short_integer_type_node)
734 return short_unsigned_type_node;
735 if (type1 == long_integer_type_node)
736 return long_unsigned_type_node;
737 if (type1 == long_long_integer_type_node)
738 return long_long_unsigned_type_node;
739 if (type1 == intDI_type_node)
740 return unsigned_intDI_type_node;
741 if (type1 == intSI_type_node)
742 return unsigned_intSI_type_node;
743 if (type1 == intHI_type_node)
744 return unsigned_intHI_type_node;
745 if (type1 == intQI_type_node)
746 return unsigned_intQI_type_node;
748 return signed_or_unsigned_type (1, type);
751 /* Return a signed type the same as TYPE in other respects. */
757 tree type1 = TYPE_MAIN_VARIANT (type);
758 if (type1 == unsigned_char_type_node || type1 == char_type_node)
759 return signed_char_type_node;
760 if (type1 == unsigned_type_node)
761 return integer_type_node;
762 if (type1 == short_unsigned_type_node)
763 return short_integer_type_node;
764 if (type1 == long_unsigned_type_node)
765 return long_integer_type_node;
766 if (type1 == long_long_unsigned_type_node)
767 return long_long_integer_type_node;
768 if (type1 == unsigned_intDI_type_node)
769 return intDI_type_node;
770 if (type1 == unsigned_intSI_type_node)
771 return intSI_type_node;
772 if (type1 == unsigned_intHI_type_node)
773 return intHI_type_node;
774 if (type1 == unsigned_intQI_type_node)
775 return intQI_type_node;
777 return signed_or_unsigned_type (0, type);
780 /* Return a type the same as TYPE except unsigned or
781 signed according to UNSIGNEDP. */
784 signed_or_unsigned_type (unsignedp, type)
788 if (! INTEGRAL_TYPE_P (type)
789 || TREE_UNSIGNED (type) == unsignedp)
791 if (TYPE_PRECISION (type) == TYPE_PRECISION (signed_char_type_node))
792 return unsignedp ? unsigned_char_type_node : signed_char_type_node;
793 if (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
794 return unsignedp ? unsigned_type_node : integer_type_node;
795 if (TYPE_PRECISION (type) == TYPE_PRECISION (short_integer_type_node))
796 return unsignedp ? short_unsigned_type_node : short_integer_type_node;
797 if (TYPE_PRECISION (type) == TYPE_PRECISION (long_integer_type_node))
798 return unsignedp ? long_unsigned_type_node : long_integer_type_node;
799 if (TYPE_PRECISION (type) == TYPE_PRECISION (long_long_integer_type_node))
800 return (unsignedp ? long_long_unsigned_type_node
801 : long_long_integer_type_node);
805 /* Compute the value of the `sizeof' operator. */
811 enum tree_code code = TREE_CODE (type);
814 if (code == FUNCTION_TYPE)
816 if (pedantic || warn_pointer_arith)
817 pedwarn ("sizeof applied to a function type");
820 if (code == VOID_TYPE)
822 if (pedantic || warn_pointer_arith)
823 pedwarn ("sizeof applied to a void type");
826 if (code == ERROR_MARK)
828 if (TYPE_SIZE (type) == 0)
830 error ("sizeof applied to an incomplete type");
834 /* Convert in case a char is more than one unit. */
835 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
836 size_int (TYPE_PRECISION (char_type_node)));
837 /* size_binop does not put the constant in range, so do it now. */
838 if (TREE_CODE (t) == INTEGER_CST && force_fit_type (t, 0))
839 TREE_CONSTANT_OVERFLOW (t) = TREE_OVERFLOW (t) = 1;
844 c_sizeof_nowarn (type)
847 enum tree_code code = TREE_CODE (type);
850 if (code == FUNCTION_TYPE
852 || code == ERROR_MARK)
854 if (TYPE_SIZE (type) == 0)
857 /* Convert in case a char is more than one unit. */
858 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
859 size_int (TYPE_PRECISION (char_type_node)));
860 force_fit_type (t, 0);
864 /* Compute the size to increment a pointer by. */
867 c_size_in_bytes (type)
870 enum tree_code code = TREE_CODE (type);
873 if (code == FUNCTION_TYPE)
875 if (code == VOID_TYPE)
877 if (code == ERROR_MARK)
879 if (TYPE_SIZE (type) == 0)
881 error ("arithmetic on pointer to an incomplete type");
885 /* Convert in case a char is more than one unit. */
886 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
887 size_int (BITS_PER_UNIT));
888 force_fit_type (t, 0);
892 /* Implement the __alignof keyword: Return the minimum required
893 alignment of TYPE, measured in bytes. */
899 enum tree_code code = TREE_CODE (type);
901 if (code == FUNCTION_TYPE)
902 return size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
904 if (code == VOID_TYPE || code == ERROR_MARK)
907 return size_int (TYPE_ALIGN (type) / BITS_PER_UNIT);
910 /* Implement the __alignof keyword: Return the minimum required
911 alignment of EXPR, measured in bytes. For VAR_DECL's and
912 FIELD_DECL's return DECL_ALIGN (which can be set from an
913 "aligned" __attribute__ specification). */
916 c_alignof_expr (expr)
919 if (TREE_CODE (expr) == VAR_DECL)
920 return size_int (DECL_ALIGN (expr) / BITS_PER_UNIT);
922 if (TREE_CODE (expr) == COMPONENT_REF
923 && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1)))
925 error ("`__alignof' applied to a bit-field");
928 else if (TREE_CODE (expr) == COMPONENT_REF
929 && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
930 return size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT);
932 if (TREE_CODE (expr) == INDIRECT_REF)
934 tree t = TREE_OPERAND (expr, 0);
936 int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
938 while (TREE_CODE (t) == NOP_EXPR
939 && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
943 t = TREE_OPERAND (t, 0);
944 thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
945 if (thisalign > bestalign)
946 best = t, bestalign = thisalign;
948 return c_alignof (TREE_TYPE (TREE_TYPE (best)));
951 return c_alignof (TREE_TYPE (expr));
954 /* Return either DECL or its known constant value (if it has one). */
957 decl_constant_value (decl)
960 if (/* Don't change a variable array bound or initial value to a constant
961 in a place where a variable is invalid. */
962 current_function_decl != 0
964 && ! TREE_THIS_VOLATILE (decl)
965 && TREE_READONLY (decl) && ! ITERATOR_P (decl)
966 && DECL_INITIAL (decl) != 0
967 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
968 /* This is invalid if initial value is not constant.
969 If it has either a function call, a memory reference,
970 or a variable, then re-evaluating it could give different results. */
971 && TREE_CONSTANT (DECL_INITIAL (decl))
972 /* Check for cases where this is sub-optimal, even though valid. */
973 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR
974 && DECL_MODE (decl) != BLKmode)
975 return DECL_INITIAL (decl);
979 /* Perform default promotions for C data used in expressions.
980 Arrays and functions are converted to pointers;
981 enumeral types or short or char, to int.
982 In addition, manifest constants symbols are replaced by their values. */
985 default_conversion (exp)
988 register tree type = TREE_TYPE (exp);
989 register enum tree_code code = TREE_CODE (type);
991 /* Constants can be used directly unless they're not loadable. */
992 if (TREE_CODE (exp) == CONST_DECL)
993 exp = DECL_INITIAL (exp);
995 /* Replace a nonvolatile const static variable with its value unless
996 it is an array, in which case we must be sure that taking the
997 address of the array produces consistent results. */
998 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
1000 exp = decl_constant_value (exp);
1001 type = TREE_TYPE (exp);
1004 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
1006 /* Do not use STRIP_NOPS here! It will remove conversions from pointer
1007 to integer and cause infinite recursion. */
1008 while (TREE_CODE (exp) == NON_LVALUE_EXPR
1009 || (TREE_CODE (exp) == NOP_EXPR
1010 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
1011 exp = TREE_OPERAND (exp, 0);
1013 /* Normally convert enums to int,
1014 but convert wide enums to something wider. */
1015 if (code == ENUMERAL_TYPE)
1017 type = type_for_size (MAX (TYPE_PRECISION (type),
1018 TYPE_PRECISION (integer_type_node)),
1020 || (TYPE_PRECISION (type)
1021 >= TYPE_PRECISION (integer_type_node)))
1022 && TREE_UNSIGNED (type)));
1023 return convert (type, exp);
1026 if (TREE_CODE (exp) == COMPONENT_REF
1027 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1)))
1029 tree width = DECL_SIZE (TREE_OPERAND (exp, 1));
1030 HOST_WIDE_INT low = TREE_INT_CST_LOW (width);
1032 /* If it's thinner than an int, promote it like a
1033 C_PROMOTING_INTEGER_TYPE_P, otherwise leave it alone. */
1035 if (low < TYPE_PRECISION (integer_type_node))
1037 if (flag_traditional && TREE_UNSIGNED (type))
1038 return convert (unsigned_type_node, exp);
1040 return convert (integer_type_node, exp);
1044 if (C_PROMOTING_INTEGER_TYPE_P (type))
1046 /* Traditionally, unsignedness is preserved in default promotions.
1047 Also preserve unsignedness if not really getting any wider. */
1048 if (TREE_UNSIGNED (type)
1049 && (flag_traditional
1050 || TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
1051 return convert (unsigned_type_node, exp);
1052 return convert (integer_type_node, exp);
1054 if (flag_traditional && !flag_allow_single_precision
1055 && TYPE_MAIN_VARIANT (type) == float_type_node)
1056 return convert (double_type_node, exp);
1057 if (code == VOID_TYPE)
1059 error ("void value not ignored as it ought to be");
1060 return error_mark_node;
1062 if (code == FUNCTION_TYPE)
1064 return build_unary_op (ADDR_EXPR, exp, 0);
1066 if (code == ARRAY_TYPE)
1069 tree restype = TREE_TYPE (type);
1074 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r'
1075 || TREE_CODE_CLASS (TREE_CODE (exp)) == 'd')
1077 constp = TREE_READONLY (exp);
1078 volatilep = TREE_THIS_VOLATILE (exp);
1081 if (TYPE_READONLY (type) || TYPE_VOLATILE (type)
1082 || constp || volatilep)
1083 restype = c_build_type_variant (restype,
1084 TYPE_READONLY (type) || constp,
1085 TYPE_VOLATILE (type) || volatilep);
1087 if (TREE_CODE (exp) == INDIRECT_REF)
1088 return convert (TYPE_POINTER_TO (restype),
1089 TREE_OPERAND (exp, 0));
1091 if (TREE_CODE (exp) == COMPOUND_EXPR)
1093 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
1094 return build (COMPOUND_EXPR, TREE_TYPE (op1),
1095 TREE_OPERAND (exp, 0), op1);
1098 if (! lvalue_p (exp)
1099 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1101 error ("invalid use of non-lvalue array");
1102 return error_mark_node;
1105 ptrtype = build_pointer_type (restype);
1107 if (TREE_CODE (exp) == VAR_DECL)
1109 /* ??? This is not really quite correct
1110 in that the type of the operand of ADDR_EXPR
1111 is not the target type of the type of the ADDR_EXPR itself.
1112 Question is, can this lossage be avoided? */
1113 adr = build1 (ADDR_EXPR, ptrtype, exp);
1114 if (mark_addressable (exp) == 0)
1115 return error_mark_node;
1116 TREE_CONSTANT (adr) = staticp (exp);
1117 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1120 /* This way is better for a COMPONENT_REF since it can
1121 simplify the offset for a component. */
1122 adr = build_unary_op (ADDR_EXPR, exp, 1);
1123 return convert (ptrtype, adr);
1128 /* Look up component name in the structure type definition.
1130 If this component name is found indirectly within an anonymous union,
1131 store in *INDIRECT the component which directly contains
1132 that anonymous union. Otherwise, set *INDIRECT to 0. */
1135 lookup_field (type, component, indirect)
1136 tree type, component;
1141 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1142 to the field elements. Use a binary search on this array to quickly
1143 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1144 will always be set for structures which have many elements. */
1146 if (TYPE_LANG_SPECIFIC (type))
1149 tree *field_array = &TYPE_LANG_SPECIFIC (type)->elts[0];
1151 field = TYPE_FIELDS (type);
1153 top = TYPE_LANG_SPECIFIC (type)->len;
1154 while (top - bot > 1)
1156 half = (top - bot + 1) >> 1;
1157 field = field_array[bot+half];
1159 if (DECL_NAME (field) == NULL_TREE)
1161 /* Step through all anon unions in linear fashion. */
1162 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1164 tree anon = 0, junk;
1166 field = field_array[bot++];
1167 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1168 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1169 anon = lookup_field (TREE_TYPE (field), component, &junk);
1171 if (anon != NULL_TREE)
1178 /* Entire record is only anon unions. */
1182 /* Restart the binary search, with new lower bound. */
1186 if (DECL_NAME (field) == component)
1188 if (DECL_NAME (field) < component)
1194 if (DECL_NAME (field_array[bot]) == component)
1195 field = field_array[bot];
1196 else if (DECL_NAME (field) != component)
1201 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1203 if (DECL_NAME (field) == NULL_TREE)
1208 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1209 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1210 anon = lookup_field (TREE_TYPE (field), component, &junk);
1212 if (anon != NULL_TREE)
1219 if (DECL_NAME (field) == component)
1224 *indirect = NULL_TREE;
1228 /* Make an expression to refer to the COMPONENT field of
1229 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1232 build_component_ref (datum, component)
1233 tree datum, component;
1235 register tree type = TREE_TYPE (datum);
1236 register enum tree_code code = TREE_CODE (type);
1237 register tree field = NULL;
1240 /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it
1241 unless we are not to support things not strictly ANSI. */
1242 switch (TREE_CODE (datum))
1246 tree value = build_component_ref (TREE_OPERAND (datum, 1), component);
1247 return build (COMPOUND_EXPR, TREE_TYPE (value),
1248 TREE_OPERAND (datum, 0), value);
1251 return build_conditional_expr
1252 (TREE_OPERAND (datum, 0),
1253 build_component_ref (TREE_OPERAND (datum, 1), component),
1254 build_component_ref (TREE_OPERAND (datum, 2), component));
1260 /* See if there is a field or component with name COMPONENT. */
1262 if (code == RECORD_TYPE || code == UNION_TYPE)
1266 if (TYPE_SIZE (type) == 0)
1268 incomplete_type_error (NULL_TREE, type);
1269 return error_mark_node;
1272 field = lookup_field (type, component, &indirect);
1276 error (code == RECORD_TYPE
1277 ? "structure has no member named `%s'"
1278 : "union has no member named `%s'",
1279 IDENTIFIER_POINTER (component));
1280 return error_mark_node;
1282 if (TREE_TYPE (field) == error_mark_node)
1283 return error_mark_node;
1285 /* If FIELD was found buried within an anonymous union,
1286 make one COMPONENT_REF to get that anonymous union,
1287 then fall thru to make a second COMPONENT_REF to get FIELD. */
1290 ref = build (COMPONENT_REF, TREE_TYPE (indirect), datum, indirect);
1291 if (TREE_READONLY (datum) || TREE_READONLY (indirect))
1292 TREE_READONLY (ref) = 1;
1293 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (indirect))
1294 TREE_THIS_VOLATILE (ref) = 1;
1298 ref = build (COMPONENT_REF, TREE_TYPE (field), datum, field);
1300 if (TREE_READONLY (datum) || TREE_READONLY (field))
1301 TREE_READONLY (ref) = 1;
1302 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (field))
1303 TREE_THIS_VOLATILE (ref) = 1;
1307 else if (code != ERROR_MARK)
1308 error ("request for member `%s' in something not a structure or union",
1309 IDENTIFIER_POINTER (component));
1311 return error_mark_node;
1314 /* Given an expression PTR for a pointer, return an expression
1315 for the value pointed to.
1316 ERRORSTRING is the name of the operator to appear in error messages. */
1319 build_indirect_ref (ptr, errorstring)
1323 register tree pointer = default_conversion (ptr);
1324 register tree type = TREE_TYPE (pointer);
1326 if (TREE_CODE (type) == POINTER_TYPE)
1328 if (TREE_CODE (pointer) == ADDR_EXPR
1330 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1331 == TREE_TYPE (type)))
1332 return TREE_OPERAND (pointer, 0);
1335 tree t = TREE_TYPE (type);
1336 register tree ref = build1 (INDIRECT_REF,
1337 TYPE_MAIN_VARIANT (t), pointer);
1339 if (TYPE_SIZE (t) == 0 && TREE_CODE (t) != ARRAY_TYPE)
1341 error ("dereferencing pointer to incomplete type");
1342 return error_mark_node;
1344 if (TREE_CODE (t) == VOID_TYPE && skip_evaluation == 0)
1345 warning ("dereferencing `void *' pointer");
1347 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1348 so that we get the proper error message if the result is used
1349 to assign to. Also, &* is supposed to be a no-op.
1350 And ANSI C seems to specify that the type of the result
1351 should be the const type. */
1352 /* A de-reference of a pointer to const is not a const. It is valid
1353 to change it via some other pointer. */
1354 TREE_READONLY (ref) = TYPE_READONLY (t);
1355 TREE_SIDE_EFFECTS (ref)
1356 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer) || flag_volatile;
1357 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1361 else if (TREE_CODE (pointer) != ERROR_MARK)
1362 error ("invalid type argument of `%s'", errorstring);
1363 return error_mark_node;
1366 /* This handles expressions of the form "a[i]", which denotes
1369 This is logically equivalent in C to *(a+i), but we may do it differently.
1370 If A is a variable or a member, we generate a primitive ARRAY_REF.
1371 This avoids forcing the array out of registers, and can work on
1372 arrays that are not lvalues (for example, members of structures returned
1376 build_array_ref (array, index)
1381 error ("subscript missing in array reference");
1382 return error_mark_node;
1385 if (TREE_TYPE (array) == error_mark_node
1386 || TREE_TYPE (index) == error_mark_node)
1387 return error_mark_node;
1389 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
1390 && TREE_CODE (array) != INDIRECT_REF)
1394 /* Subscripting with type char is likely to lose
1395 on a machine where chars are signed.
1396 So warn on any machine, but optionally.
1397 Don't warn for unsigned char since that type is safe.
1398 Don't warn for signed char because anyone who uses that
1399 must have done so deliberately. */
1400 if (warn_char_subscripts
1401 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1402 warning ("array subscript has type `char'");
1404 /* Apply default promotions *after* noticing character types. */
1405 index = default_conversion (index);
1407 /* Require integer *after* promotion, for sake of enums. */
1408 if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE)
1410 error ("array subscript is not an integer");
1411 return error_mark_node;
1414 /* An array that is indexed by a non-constant
1415 cannot be stored in a register; we must be able to do
1416 address arithmetic on its address.
1417 Likewise an array of elements of variable size. */
1418 if (TREE_CODE (index) != INTEGER_CST
1419 || (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))) != 0
1420 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1422 if (mark_addressable (array) == 0)
1423 return error_mark_node;
1425 /* An array that is indexed by a constant value which is not within
1426 the array bounds cannot be stored in a register either; because we
1427 would get a crash in store_bit_field/extract_bit_field when trying
1428 to access a non-existent part of the register. */
1429 if (TREE_CODE (index) == INTEGER_CST
1430 && TYPE_VALUES (TREE_TYPE (array))
1431 && ! int_fits_type_p (index, TYPE_VALUES (TREE_TYPE (array))))
1433 if (mark_addressable (array) == 0)
1434 return error_mark_node;
1437 if (pedantic && !lvalue_p (array))
1439 if (DECL_REGISTER (array))
1440 pedwarn ("ANSI C forbids subscripting `register' array");
1442 pedwarn ("ANSI C forbids subscripting non-lvalue array");
1448 while (TREE_CODE (foo) == COMPONENT_REF)
1449 foo = TREE_OPERAND (foo, 0);
1450 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
1451 pedwarn ("ANSI C forbids subscripting non-lvalue array");
1454 type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array)));
1455 rval = build (ARRAY_REF, type, array, index);
1456 /* Array ref is const/volatile if the array elements are
1457 or if the array is. */
1458 TREE_READONLY (rval)
1459 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1460 | TREE_READONLY (array));
1461 TREE_SIDE_EFFECTS (rval)
1462 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1463 | TREE_SIDE_EFFECTS (array));
1464 TREE_THIS_VOLATILE (rval)
1465 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1466 /* This was added by rms on 16 Nov 91.
1467 It fixes vol struct foo *a; a->elts[1]
1468 in an inline function.
1469 Hope it doesn't break something else. */
1470 | TREE_THIS_VOLATILE (array));
1471 return require_complete_type (fold (rval));
1475 tree ar = default_conversion (array);
1476 tree ind = default_conversion (index);
1478 /* Do the same warning check as above, but only on the part that's
1479 syntactically the index and only if it is also semantically
1481 if (warn_char_subscripts
1482 && TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE
1483 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1484 warning ("subscript has type `char'");
1486 /* Put the integer in IND to simplify error checking. */
1487 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
1494 if (ar == error_mark_node)
1497 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE
1498 || TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) == FUNCTION_TYPE)
1500 error ("subscripted value is neither array nor pointer");
1501 return error_mark_node;
1503 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
1505 error ("array subscript is not an integer");
1506 return error_mark_node;
1509 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0),
1514 /* Build a function call to function FUNCTION with parameters PARAMS.
1515 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1516 TREE_VALUE of each node is a parameter-expression.
1517 FUNCTION's data type may be a function type or a pointer-to-function. */
1520 build_function_call (function, params)
1521 tree function, params;
1523 register tree fntype, fundecl = 0;
1524 register tree coerced_params;
1525 tree name = NULL_TREE, assembler_name = NULL_TREE;
1527 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1528 STRIP_TYPE_NOPS (function);
1530 /* Convert anything with function type to a pointer-to-function. */
1531 if (TREE_CODE (function) == FUNCTION_DECL)
1533 name = DECL_NAME (function);
1534 assembler_name = DECL_ASSEMBLER_NAME (function);
1536 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1537 (because calling an inline function does not mean the function
1538 needs to be separately compiled). */
1539 fntype = build_type_variant (TREE_TYPE (function),
1540 TREE_READONLY (function),
1541 TREE_THIS_VOLATILE (function));
1543 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
1546 function = default_conversion (function);
1548 fntype = TREE_TYPE (function);
1550 if (TREE_CODE (fntype) == ERROR_MARK)
1551 return error_mark_node;
1553 if (!(TREE_CODE (fntype) == POINTER_TYPE
1554 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
1556 error ("called object is not a function");
1557 return error_mark_node;
1560 /* fntype now gets the type of function pointed to. */
1561 fntype = TREE_TYPE (fntype);
1563 /* Convert the parameters to the types declared in the
1564 function prototype, or apply default promotions. */
1567 = convert_arguments (TYPE_ARG_TYPES (fntype), params, name, fundecl);
1569 /* Check for errors in format strings. */
1571 if (warn_format && (name || assembler_name))
1572 check_function_format (name, assembler_name, coerced_params);
1574 /* Recognize certain built-in functions so we can make tree-codes
1575 other than CALL_EXPR. We do this when it enables fold-const.c
1576 to do something useful. */
1578 if (TREE_CODE (function) == ADDR_EXPR
1579 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
1580 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
1581 switch (DECL_FUNCTION_CODE (TREE_OPERAND (function, 0)))
1586 if (coerced_params == 0)
1587 return integer_zero_node;
1588 return build_unary_op (ABS_EXPR, TREE_VALUE (coerced_params), 0);
1594 register tree result
1595 = build (CALL_EXPR, TREE_TYPE (fntype),
1596 function, coerced_params, NULL_TREE);
1598 TREE_SIDE_EFFECTS (result) = 1;
1599 if (TREE_TYPE (result) == void_type_node)
1601 return require_complete_type (result);
1605 /* Convert the argument expressions in the list VALUES
1606 to the types in the list TYPELIST. The result is a list of converted
1607 argument expressions.
1609 If TYPELIST is exhausted, or when an element has NULL as its type,
1610 perform the default conversions.
1612 PARMLIST is the chain of parm decls for the function being called.
1613 It may be 0, if that info is not available.
1614 It is used only for generating error messages.
1616 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1618 This is also where warnings about wrong number of args are generated.
1620 Both VALUES and the returned value are chains of TREE_LIST nodes
1621 with the elements of the list in the TREE_VALUE slots of those nodes. */
1624 convert_arguments (typelist, values, name, fundecl)
1625 tree typelist, values, name, fundecl;
1627 register tree typetail, valtail;
1628 register tree result = NULL;
1631 /* Scan the given expressions and types, producing individual
1632 converted arguments and pushing them on RESULT in reverse order. */
1634 for (valtail = values, typetail = typelist, parmnum = 0;
1636 valtail = TREE_CHAIN (valtail), parmnum++)
1638 register tree type = typetail ? TREE_VALUE (typetail) : 0;
1639 register tree val = TREE_VALUE (valtail);
1641 if (type == void_type_node)
1644 error ("too many arguments to function `%s'",
1645 IDENTIFIER_POINTER (name));
1647 error ("too many arguments to function");
1651 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1652 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1653 to convert automatically to a pointer. */
1654 if (TREE_CODE (val) == NON_LVALUE_EXPR)
1655 val = TREE_OPERAND (val, 0);
1657 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
1658 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE)
1659 val = default_conversion (val);
1661 val = require_complete_type (val);
1665 /* Formal parm type is specified by a function prototype. */
1668 if (TYPE_SIZE (type) == 0)
1670 error ("type of formal parameter %d is incomplete", parmnum + 1);
1675 /* Optionally warn about conversions that
1676 differ from the default conversions. */
1677 if (warn_conversion)
1679 int formal_prec = TYPE_PRECISION (type);
1681 if (INTEGRAL_TYPE_P (type)
1682 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1683 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1684 else if (TREE_CODE (type) == COMPLEX_TYPE
1685 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1686 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1687 else if (TREE_CODE (type) == REAL_TYPE
1688 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1689 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1690 else if (TREE_CODE (type) == REAL_TYPE
1691 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
1692 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1693 /* ??? At some point, messages should be written about
1694 conversions between complex types, but that's too messy
1696 else if (TREE_CODE (type) == REAL_TYPE
1697 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1699 /* Warn if any argument is passed as `float',
1700 since without a prototype it would be `double'. */
1701 if (formal_prec == TYPE_PRECISION (float_type_node))
1702 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1704 /* Detect integer changing in width or signedness. */
1705 else if (INTEGRAL_TYPE_P (type)
1706 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1708 tree would_have_been = default_conversion (val);
1709 tree type1 = TREE_TYPE (would_have_been);
1711 if (TREE_CODE (type) == ENUMERAL_TYPE
1712 && type == TREE_TYPE (val))
1713 /* No warning if function asks for enum
1714 and the actual arg is that enum type. */
1716 else if (formal_prec != TYPE_PRECISION (type1))
1717 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1718 else if (TREE_UNSIGNED (type) == TREE_UNSIGNED (type1))
1720 /* Don't complain if the formal parameter type
1721 is an enum, because we can't tell now whether
1722 the value was an enum--even the same enum. */
1723 else if (TREE_CODE (type) == ENUMERAL_TYPE)
1725 else if (TREE_CODE (val) == INTEGER_CST
1726 && int_fits_type_p (val, type))
1727 /* Change in signedness doesn't matter
1728 if a constant value is unaffected. */
1730 /* Likewise for a constant in a NOP_EXPR. */
1731 else if (TREE_CODE (val) == NOP_EXPR
1732 && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST
1733 && int_fits_type_p (TREE_OPERAND (val, 0), type))
1735 #if 0 /* We never get such tree structure here. */
1736 else if (TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE
1737 && int_fits_type_p (TYPE_MIN_VALUE (TREE_TYPE (val)), type)
1738 && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE (val)), type))
1739 /* Change in signedness doesn't matter
1740 if an enum value is unaffected. */
1743 /* If the value is extended from a narrower
1744 unsigned type, it doesn't matter whether we
1745 pass it as signed or unsigned; the value
1746 certainly is the same either way. */
1747 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
1748 && TREE_UNSIGNED (TREE_TYPE (val)))
1750 else if (TREE_UNSIGNED (type))
1751 warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1);
1753 warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1);
1757 parmval = convert_for_assignment (type, val,
1758 (char *) 0, /* arg passing */
1759 fundecl, name, parmnum + 1);
1761 #ifdef PROMOTE_PROTOTYPES
1762 if ((TREE_CODE (type) == INTEGER_TYPE
1763 || TREE_CODE (type) == ENUMERAL_TYPE)
1764 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
1765 parmval = default_conversion (parmval);
1768 result = tree_cons (NULL_TREE, parmval, result);
1770 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
1771 && (TYPE_PRECISION (TREE_TYPE (val))
1772 < TYPE_PRECISION (double_type_node)))
1773 /* Convert `float' to `double'. */
1774 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
1776 /* Convert `short' and `char' to full-size `int'. */
1777 result = tree_cons (NULL_TREE, default_conversion (val), result);
1780 typetail = TREE_CHAIN (typetail);
1783 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
1786 error ("too few arguments to function `%s'",
1787 IDENTIFIER_POINTER (name));
1789 error ("too few arguments to function");
1792 return nreverse (result);
1795 /* This is the entry point used by the parser
1796 for binary operators in the input.
1797 In addition to constructing the expression,
1798 we check for operands that were written with other binary operators
1799 in a way that is likely to confuse the user. */
1802 parser_build_binary_op (code, arg1, arg2)
1803 enum tree_code code;
1806 tree result = build_binary_op (code, arg1, arg2, 1);
1809 char class1 = TREE_CODE_CLASS (TREE_CODE (arg1));
1810 char class2 = TREE_CODE_CLASS (TREE_CODE (arg2));
1811 enum tree_code code1 = ERROR_MARK;
1812 enum tree_code code2 = ERROR_MARK;
1814 if (class1 == 'e' || class1 == '1'
1815 || class1 == '2' || class1 == '<')
1816 code1 = C_EXP_ORIGINAL_CODE (arg1);
1817 if (class2 == 'e' || class2 == '1'
1818 || class2 == '2' || class2 == '<')
1819 code2 = C_EXP_ORIGINAL_CODE (arg2);
1821 /* Check for cases such as x+y<<z which users are likely
1822 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1823 is cleared to prevent these warnings. */
1824 if (warn_parentheses)
1826 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
1828 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1829 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1830 warning ("suggest parentheses around + or - inside shift");
1833 if (code == TRUTH_ORIF_EXPR)
1835 if (code1 == TRUTH_ANDIF_EXPR
1836 || code2 == TRUTH_ANDIF_EXPR)
1837 warning ("suggest parentheses around && within ||");
1840 if (code == BIT_IOR_EXPR)
1842 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
1843 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1844 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
1845 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1846 warning ("suggest parentheses around arithmetic in operand of |");
1847 /* Check cases like x|y==z */
1848 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1849 warning ("suggest parentheses around comparison in operand of |");
1852 if (code == BIT_XOR_EXPR)
1854 if (code1 == BIT_AND_EXPR
1855 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1856 || code2 == BIT_AND_EXPR
1857 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1858 warning ("suggest parentheses around arithmetic in operand of ^");
1859 /* Check cases like x^y==z */
1860 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1861 warning ("suggest parentheses around comparison in operand of ^");
1864 if (code == BIT_AND_EXPR)
1866 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1867 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1868 warning ("suggest parentheses around + or - in operand of &");
1869 /* Check cases like x&y==z */
1870 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1871 warning ("suggest parentheses around comparison in operand of &");
1875 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1876 if (TREE_CODE_CLASS (code) == '<' && extra_warnings
1877 && (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<'))
1878 warning ("comparisons like X<=Y<=Z do not have their mathematical meaning");
1880 unsigned_conversion_warning (result, arg1);
1881 unsigned_conversion_warning (result, arg2);
1882 overflow_warning (result);
1884 class = TREE_CODE_CLASS (TREE_CODE (result));
1886 /* Record the code that was specified in the source,
1887 for the sake of warnings about confusing nesting. */
1888 if (class == 'e' || class == '1'
1889 || class == '2' || class == '<')
1890 C_SET_EXP_ORIGINAL_CODE (result, code);
1893 int flag = TREE_CONSTANT (result);
1894 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1895 so that convert_for_assignment wouldn't strip it.
1896 That way, we got warnings for things like p = (1 - 1).
1897 But it turns out we should not get those warnings. */
1898 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
1899 C_SET_EXP_ORIGINAL_CODE (result, code);
1900 TREE_CONSTANT (result) = flag;
1906 /* Build a binary-operation expression without default conversions.
1907 CODE is the kind of expression to build.
1908 This function differs from `build' in several ways:
1909 the data type of the result is computed and recorded in it,
1910 warnings are generated if arg data types are invalid,
1911 special handling for addition and subtraction of pointers is known,
1912 and some optimization is done (operations on narrow ints
1913 are done in the narrower type when that gives the same result).
1914 Constant folding is also done before the result is returned.
1916 Note that the operands will never have enumeral types, or function
1917 or array types, because either they will have the default conversions
1918 performed or they have both just been converted to some other type in which
1919 the arithmetic is to be done. */
1922 build_binary_op (code, orig_op0, orig_op1, convert_p)
1923 enum tree_code code;
1924 tree orig_op0, orig_op1;
1928 register enum tree_code code0, code1;
1931 /* Expression code to give to the expression when it is built.
1932 Normally this is CODE, which is what the caller asked for,
1933 but in some special cases we change it. */
1934 register enum tree_code resultcode = code;
1936 /* Data type in which the computation is to be performed.
1937 In the simplest cases this is the common type of the arguments. */
1938 register tree result_type = NULL;
1940 /* Nonzero means operands have already been type-converted
1941 in whatever way is necessary.
1942 Zero means they need to be converted to RESULT_TYPE. */
1945 /* Nonzero means create the expression with this type, rather than
1947 tree build_type = 0;
1949 /* Nonzero means after finally constructing the expression
1950 convert it to this type. */
1951 tree final_type = 0;
1953 /* Nonzero if this is an operation like MIN or MAX which can
1954 safely be computed in short if both args are promoted shorts.
1955 Also implies COMMON.
1956 -1 indicates a bitwise operation; this makes a difference
1957 in the exact conditions for when it is safe to do the operation
1958 in a narrower mode. */
1961 /* Nonzero if this is a comparison operation;
1962 if both args are promoted shorts, compare the original shorts.
1963 Also implies COMMON. */
1964 int short_compare = 0;
1966 /* Nonzero if this is a right-shift operation, which can be computed on the
1967 original short and then promoted if the operand is a promoted short. */
1968 int short_shift = 0;
1970 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1975 op0 = default_conversion (orig_op0);
1976 op1 = default_conversion (orig_op1);
1984 type0 = TREE_TYPE (op0);
1985 type1 = TREE_TYPE (op1);
1987 /* The expression codes of the data types of the arguments tell us
1988 whether the arguments are integers, floating, pointers, etc. */
1989 code0 = TREE_CODE (type0);
1990 code1 = TREE_CODE (type1);
1992 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1993 STRIP_TYPE_NOPS (op0);
1994 STRIP_TYPE_NOPS (op1);
1996 /* If an error was already reported for one of the arguments,
1997 avoid reporting another error. */
1999 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
2000 return error_mark_node;
2005 /* Handle the pointer + int case. */
2006 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2007 return pointer_int_sum (PLUS_EXPR, op0, op1);
2008 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
2009 return pointer_int_sum (PLUS_EXPR, op1, op0);
2015 /* Subtraction of two similar pointers.
2016 We must subtract them as integers, then divide by object size. */
2017 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
2018 && comp_target_types (type0, type1))
2019 return pointer_diff (op0, op1);
2020 /* Handle pointer minus int. Just like pointer plus int. */
2021 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2022 return pointer_int_sum (MINUS_EXPR, op0, op1);
2031 case TRUNC_DIV_EXPR:
2033 case FLOOR_DIV_EXPR:
2034 case ROUND_DIV_EXPR:
2035 case EXACT_DIV_EXPR:
2036 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2037 || code0 == COMPLEX_TYPE)
2038 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2039 || code1 == COMPLEX_TYPE))
2041 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
2042 resultcode = RDIV_EXPR;
2045 /* Although it would be tempting to shorten always here, that
2046 loses on some targets, since the modulo instruction is
2047 undefined if the quotient can't be represented in the
2048 computation mode. We shorten only if unsigned or if
2049 dividing by something we know != -1. */
2050 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
2051 || (TREE_CODE (op1) == INTEGER_CST
2052 && (TREE_INT_CST_LOW (op1) != -1
2053 || TREE_INT_CST_HIGH (op1) != -1)));
2060 case BIT_ANDTC_EXPR:
2063 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2065 /* If one operand is a constant, and the other is a short type
2066 that has been converted to an int,
2067 really do the work in the short type and then convert the
2068 result to int. If we are lucky, the constant will be 0 or 1
2069 in the short type, making the entire operation go away. */
2070 if (TREE_CODE (op0) == INTEGER_CST
2071 && TREE_CODE (op1) == NOP_EXPR
2072 && TYPE_PRECISION (type1) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))
2073 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0))))
2075 final_type = result_type;
2076 op1 = TREE_OPERAND (op1, 0);
2077 result_type = TREE_TYPE (op1);
2079 if (TREE_CODE (op1) == INTEGER_CST
2080 && TREE_CODE (op0) == NOP_EXPR
2081 && TYPE_PRECISION (type0) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))
2082 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2084 final_type = result_type;
2085 op0 = TREE_OPERAND (op0, 0);
2086 result_type = TREE_TYPE (op0);
2090 case TRUNC_MOD_EXPR:
2091 case FLOOR_MOD_EXPR:
2092 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2094 /* Although it would be tempting to shorten always here, that loses
2095 on some targets, since the modulo instruction is undefined if the
2096 quotient can't be represented in the computation mode. We shorten
2097 only if unsigned or if dividing by something we know != -1. */
2098 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
2099 || (TREE_CODE (op1) == INTEGER_CST
2100 && (TREE_INT_CST_LOW (op1) != -1
2101 || TREE_INT_CST_HIGH (op1) != -1)));
2106 case TRUTH_ANDIF_EXPR:
2107 case TRUTH_ORIF_EXPR:
2108 case TRUTH_AND_EXPR:
2110 case TRUTH_XOR_EXPR:
2111 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
2112 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2113 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
2114 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2116 /* Result of these operations is always an int,
2117 but that does not mean the operands should be
2118 converted to ints! */
2119 result_type = integer_type_node;
2120 op0 = truthvalue_conversion (op0);
2121 op1 = truthvalue_conversion (op1);
2126 /* Shift operations: result has same type as first operand;
2127 always convert second operand to int.
2128 Also set SHORT_SHIFT if shifting rightward. */
2131 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2133 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2135 if (tree_int_cst_sgn (op1) < 0)
2136 warning ("right shift count is negative");
2139 if (TREE_INT_CST_LOW (op1) | TREE_INT_CST_HIGH (op1))
2141 if (TREE_INT_CST_HIGH (op1) != 0
2142 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2143 >= TYPE_PRECISION (type0)))
2144 warning ("right shift count >= width of type");
2147 /* Use the type of the value to be shifted.
2148 This is what most traditional C compilers do. */
2149 result_type = type0;
2150 /* Unless traditional, convert the shift-count to an integer,
2151 regardless of size of value being shifted. */
2152 if (! flag_traditional)
2154 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2155 op1 = convert (integer_type_node, op1);
2156 /* Avoid converting op1 to result_type later. */
2163 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2165 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2167 if (tree_int_cst_sgn (op1) < 0)
2168 warning ("left shift count is negative");
2169 else if (TREE_INT_CST_HIGH (op1) != 0
2170 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2171 >= TYPE_PRECISION (type0)))
2172 warning ("left shift count >= width of type");
2174 /* Use the type of the value to be shifted.
2175 This is what most traditional C compilers do. */
2176 result_type = type0;
2177 /* Unless traditional, convert the shift-count to an integer,
2178 regardless of size of value being shifted. */
2179 if (! flag_traditional)
2181 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2182 op1 = convert (integer_type_node, op1);
2183 /* Avoid converting op1 to result_type later. */
2191 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2193 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2195 if (tree_int_cst_sgn (op1) < 0)
2196 warning ("shift count is negative");
2197 else if (TREE_INT_CST_HIGH (op1) != 0
2198 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2199 >= TYPE_PRECISION (type0)))
2200 warning ("shift count >= width of type");
2202 /* Use the type of the value to be shifted.
2203 This is what most traditional C compilers do. */
2204 result_type = type0;
2205 /* Unless traditional, convert the shift-count to an integer,
2206 regardless of size of value being shifted. */
2207 if (! flag_traditional)
2209 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2210 op1 = convert (integer_type_node, op1);
2211 /* Avoid converting op1 to result_type later. */
2219 /* Result of comparison is always int,
2220 but don't convert the args to int! */
2221 build_type = integer_type_node;
2222 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2223 || code0 == COMPLEX_TYPE)
2224 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2225 || code1 == COMPLEX_TYPE))
2227 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2229 register tree tt0 = TREE_TYPE (type0);
2230 register tree tt1 = TREE_TYPE (type1);
2231 /* Anything compares with void *. void * compares with anything.
2232 Otherwise, the targets must be compatible
2233 and both must be object or both incomplete. */
2234 if (comp_target_types (type0, type1))
2235 result_type = common_type (type0, type1);
2236 else if (TYPE_MAIN_VARIANT (tt0) == void_type_node)
2238 /* op0 != orig_op0 detects the case of something
2239 whose value is 0 but which isn't a valid null ptr const. */
2240 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
2241 && TREE_CODE (tt1) == FUNCTION_TYPE)
2242 pedwarn ("ANSI C forbids comparison of `void *' with function pointer");
2244 else if (TYPE_MAIN_VARIANT (tt1) == void_type_node)
2246 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
2247 && TREE_CODE (tt0) == FUNCTION_TYPE)
2248 pedwarn ("ANSI C forbids comparison of `void *' with function pointer");
2251 pedwarn ("comparison of distinct pointer types lacks a cast");
2253 if (result_type == NULL_TREE)
2254 result_type = ptr_type_node;
2256 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2257 && integer_zerop (op1))
2258 result_type = type0;
2259 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2260 && integer_zerop (op0))
2261 result_type = type1;
2262 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2264 result_type = type0;
2265 if (! flag_traditional)
2266 pedwarn ("comparison between pointer and integer");
2268 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2270 result_type = type1;
2271 if (! flag_traditional)
2272 pedwarn ("comparison between pointer and integer");
2278 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2279 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2281 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2283 if (comp_target_types (type0, type1))
2285 result_type = common_type (type0, type1);
2287 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2288 pedwarn ("ANSI C forbids ordered comparisons of pointers to functions");
2292 result_type = ptr_type_node;
2293 pedwarn ("comparison of distinct pointer types lacks a cast");
2302 build_type = integer_type_node;
2303 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2304 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2306 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2308 if (comp_target_types (type0, type1))
2310 result_type = common_type (type0, type1);
2311 if ((TYPE_SIZE (TREE_TYPE (type0)) != 0)
2312 != (TYPE_SIZE (TREE_TYPE (type1)) != 0))
2313 pedwarn ("comparison of complete and incomplete pointers");
2315 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2316 pedwarn ("ANSI C forbids ordered comparisons of pointers to functions");
2320 result_type = ptr_type_node;
2321 pedwarn ("comparison of distinct pointer types lacks a cast");
2324 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2325 && integer_zerop (op1))
2327 result_type = type0;
2328 if (pedantic || extra_warnings)
2329 pedwarn ("ordered comparison of pointer with integer zero");
2331 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2332 && integer_zerop (op0))
2334 result_type = type1;
2336 pedwarn ("ordered comparison of pointer with integer zero");
2338 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2340 result_type = type0;
2341 if (! flag_traditional)
2342 pedwarn ("comparison between pointer and integer");
2344 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2346 result_type = type1;
2347 if (! flag_traditional)
2348 pedwarn ("comparison between pointer and integer");
2356 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2358 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2360 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
2362 if (shorten || common || short_compare)
2363 result_type = common_type (type0, type1);
2365 /* For certain operations (which identify themselves by shorten != 0)
2366 if both args were extended from the same smaller type,
2367 do the arithmetic in that type and then extend.
2369 shorten !=0 and !=1 indicates a bitwise operation.
2370 For them, this optimization is safe only if
2371 both args are zero-extended or both are sign-extended.
2372 Otherwise, we might change the result.
2373 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2374 but calculated in (unsigned short) it would be (unsigned short)-1. */
2376 if (shorten && none_complex)
2378 int unsigned0, unsigned1;
2379 tree arg0 = get_narrower (op0, &unsigned0);
2380 tree arg1 = get_narrower (op1, &unsigned1);
2381 /* UNS is 1 if the operation to be done is an unsigned one. */
2382 int uns = TREE_UNSIGNED (result_type);
2385 final_type = result_type;
2387 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2388 but it *requires* conversion to FINAL_TYPE. */
2390 if ((TYPE_PRECISION (TREE_TYPE (op0))
2391 == TYPE_PRECISION (TREE_TYPE (arg0)))
2392 && TREE_TYPE (op0) != final_type)
2393 unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
2394 if ((TYPE_PRECISION (TREE_TYPE (op1))
2395 == TYPE_PRECISION (TREE_TYPE (arg1)))
2396 && TREE_TYPE (op1) != final_type)
2397 unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
2399 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2401 /* For bitwise operations, signedness of nominal type
2402 does not matter. Consider only how operands were extended. */
2406 /* Note that in all three cases below we refrain from optimizing
2407 an unsigned operation on sign-extended args.
2408 That would not be valid. */
2410 /* Both args variable: if both extended in same way
2411 from same width, do it in that width.
2412 Do it unsigned if args were zero-extended. */
2413 if ((TYPE_PRECISION (TREE_TYPE (arg0))
2414 < TYPE_PRECISION (result_type))
2415 && (TYPE_PRECISION (TREE_TYPE (arg1))
2416 == TYPE_PRECISION (TREE_TYPE (arg0)))
2417 && unsigned0 == unsigned1
2418 && (unsigned0 || !uns))
2420 = signed_or_unsigned_type (unsigned0,
2421 common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
2422 else if (TREE_CODE (arg0) == INTEGER_CST
2423 && (unsigned1 || !uns)
2424 && (TYPE_PRECISION (TREE_TYPE (arg1))
2425 < TYPE_PRECISION (result_type))
2426 && (type = signed_or_unsigned_type (unsigned1,
2428 int_fits_type_p (arg0, type)))
2430 else if (TREE_CODE (arg1) == INTEGER_CST
2431 && (unsigned0 || !uns)
2432 && (TYPE_PRECISION (TREE_TYPE (arg0))
2433 < TYPE_PRECISION (result_type))
2434 && (type = signed_or_unsigned_type (unsigned0,
2436 int_fits_type_p (arg1, type)))
2440 /* Shifts can be shortened if shifting right. */
2445 tree arg0 = get_narrower (op0, &unsigned_arg);
2447 final_type = result_type;
2449 if (arg0 == op0 && final_type == TREE_TYPE (op0))
2450 unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
2452 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
2453 /* We can shorten only if the shift count is less than the
2454 number of bits in the smaller type size. */
2455 && TREE_INT_CST_HIGH (op1) == 0
2456 && TYPE_PRECISION (TREE_TYPE (arg0)) > TREE_INT_CST_LOW (op1)
2457 /* If arg is sign-extended and then unsigned-shifted,
2458 we can simulate this with a signed shift in arg's type
2459 only if the extended result is at least twice as wide
2460 as the arg. Otherwise, the shift could use up all the
2461 ones made by sign-extension and bring in zeros.
2462 We can't optimize that case at all, but in most machines
2463 it never happens because available widths are 2**N. */
2464 && (!TREE_UNSIGNED (final_type)
2466 || 2 * TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (result_type)))
2468 /* Do an unsigned shift if the operand was zero-extended. */
2470 = signed_or_unsigned_type (unsigned_arg,
2472 /* Convert value-to-be-shifted to that type. */
2473 if (TREE_TYPE (op0) != result_type)
2474 op0 = convert (result_type, op0);
2479 /* Comparison operations are shortened too but differently.
2480 They identify themselves by setting short_compare = 1. */
2484 /* Don't write &op0, etc., because that would prevent op0
2485 from being kept in a register.
2486 Instead, make copies of the our local variables and
2487 pass the copies by reference, then copy them back afterward. */
2488 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
2489 enum tree_code xresultcode = resultcode;
2491 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
2494 op0 = xop0, op1 = xop1;
2496 resultcode = xresultcode;
2498 if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare != 0)
2499 && skip_evaluation == 0)
2501 int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0));
2502 int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1));
2504 int unsignedp0, unsignedp1;
2505 tree primop0 = get_narrower (op0, &unsignedp0);
2506 tree primop1 = get_narrower (op1, &unsignedp1);
2508 /* Avoid spurious warnings for comparison with enumerators. */
2512 STRIP_TYPE_NOPS (xop0);
2513 STRIP_TYPE_NOPS (xop1);
2515 /* Give warnings for comparisons between signed and unsigned
2516 quantities that may fail. */
2517 /* Do the checking based on the original operand trees, so that
2518 casts will be considered, but default promotions won't be. */
2520 /* Do not warn if the comparison is being done in a signed type,
2521 since the signed type will only be chosen if it can represent
2522 all the values of the unsigned type. */
2523 if (! TREE_UNSIGNED (result_type))
2525 /* Do not warn if both operands are unsigned. */
2526 else if (op0_signed == op1_signed)
2528 /* Do not warn if the signed quantity is an unsuffixed
2529 integer literal (or some static constant expression
2530 involving such literals) and it is non-negative. */
2531 else if ((op0_signed && TREE_CODE (xop0) == INTEGER_CST
2532 && tree_int_cst_sgn (xop0) >= 0)
2533 || (op1_signed && TREE_CODE (xop1) == INTEGER_CST
2534 && tree_int_cst_sgn (xop1) >= 0))
2536 /* Do not warn if the comparison is an equality operation,
2537 the unsigned quantity is an integral constant and it does
2538 not use the most significant bit of result_type. */
2539 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
2540 && ((op0_signed && TREE_CODE (xop1) == INTEGER_CST
2541 && int_fits_type_p (xop1, signed_type (result_type)))
2542 || (op1_signed && TREE_CODE (xop0) == INTEGER_CST
2543 && int_fits_type_p (xop0, signed_type (result_type)))))
2546 warning ("comparison between signed and unsigned");
2548 /* Warn if two unsigned values are being compared in a size
2549 larger than their original size, and one (and only one) is the
2550 result of a `~' operator. This comparison will always fail.
2552 Also warn if one operand is a constant, and the constant
2553 does not have all bits set that are set in the ~ operand
2554 when it is extended. */
2556 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
2557 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
2559 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
2560 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
2563 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
2566 if (TREE_CODE (primop0) == INTEGER_CST
2567 || TREE_CODE (primop1) == INTEGER_CST)
2570 long constant, mask;
2571 int unsignedp, bits;
2573 if (TREE_CODE (primop0) == INTEGER_CST)
2576 unsignedp = unsignedp1;
2577 constant = TREE_INT_CST_LOW (primop0);
2582 unsignedp = unsignedp0;
2583 constant = TREE_INT_CST_LOW (primop1);
2586 bits = TYPE_PRECISION (TREE_TYPE (primop));
2587 if (bits < TYPE_PRECISION (result_type)
2588 && bits < HOST_BITS_PER_LONG && unsignedp)
2590 mask = (~0L) << bits;
2591 if ((mask & constant) != mask)
2592 warning ("comparison of promoted ~unsigned with constant");
2595 else if (unsignedp0 && unsignedp1
2596 && (TYPE_PRECISION (TREE_TYPE (primop0))
2597 < TYPE_PRECISION (result_type))
2598 && (TYPE_PRECISION (TREE_TYPE (primop1))
2599 < TYPE_PRECISION (result_type)))
2600 warning ("comparison of promoted ~unsigned with unsigned");
2606 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2607 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2608 Then the expression will be built.
2609 It will be given type FINAL_TYPE if that is nonzero;
2610 otherwise, it will be given type RESULT_TYPE. */
2614 binary_op_error (code);
2615 return error_mark_node;
2620 if (TREE_TYPE (op0) != result_type)
2621 op0 = convert (result_type, op0);
2622 if (TREE_TYPE (op1) != result_type)
2623 op1 = convert (result_type, op1);
2626 if (build_type == NULL_TREE)
2627 build_type = result_type;
2630 register tree result = build (resultcode, build_type, op0, op1);
2631 register tree folded;
2633 folded = fold (result);
2634 if (folded == result)
2635 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2636 if (final_type != 0)
2637 return convert (final_type, folded);
2642 /* Return a tree for the sum or difference (RESULTCODE says which)
2643 of pointer PTROP and integer INTOP. */
2646 pointer_int_sum (resultcode, ptrop, intop)
2647 enum tree_code resultcode;
2648 register tree ptrop, intop;
2652 register tree result;
2653 register tree folded;
2655 /* The result is a pointer of the same type that is being added. */
2657 register tree result_type = TREE_TYPE (ptrop);
2659 if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
2661 if (pedantic || warn_pointer_arith)
2662 pedwarn ("pointer of type `void *' used in arithmetic");
2663 size_exp = integer_one_node;
2665 else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
2667 if (pedantic || warn_pointer_arith)
2668 pedwarn ("pointer to a function used in arithmetic");
2669 size_exp = integer_one_node;
2672 size_exp = c_size_in_bytes (TREE_TYPE (result_type));
2674 /* If what we are about to multiply by the size of the elements
2675 contains a constant term, apply distributive law
2676 and multiply that constant term separately.
2677 This helps produce common subexpressions. */
2679 if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
2680 && ! TREE_CONSTANT (intop)
2681 && TREE_CONSTANT (TREE_OPERAND (intop, 1))
2682 && TREE_CONSTANT (size_exp)
2683 /* If the constant comes from pointer subtraction,
2684 skip this optimization--it would cause an error. */
2685 && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE
2686 /* If the constant is unsigned, and smaller than the pointer size,
2687 then we must skip this optimization. This is because it could cause
2688 an overflow error if the constant is negative but INTOP is not. */
2689 && (! TREE_UNSIGNED (TREE_TYPE (intop))
2690 || (TYPE_PRECISION (TREE_TYPE (intop))
2691 == TYPE_PRECISION (TREE_TYPE (ptrop)))))
2693 enum tree_code subcode = resultcode;
2694 tree int_type = TREE_TYPE (intop);
2695 if (TREE_CODE (intop) == MINUS_EXPR)
2696 subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
2697 /* Convert both subexpression types to the type of intop,
2698 because weird cases involving pointer arithmetic
2699 can result in a sum or difference with different type args. */
2700 ptrop = build_binary_op (subcode, ptrop,
2701 convert (int_type, TREE_OPERAND (intop, 1)), 1);
2702 intop = convert (int_type, TREE_OPERAND (intop, 0));
2705 /* Convert the integer argument to a type the same size as sizetype
2706 so the multiply won't overflow spuriously. */
2708 if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype)
2709 || TREE_UNSIGNED (TREE_TYPE (intop)) != TREE_UNSIGNED (sizetype))
2710 intop = convert (type_for_size (TYPE_PRECISION (sizetype),
2711 TREE_UNSIGNED (sizetype)), intop);
2713 /* Replace the integer argument with a suitable product by the object size.
2714 Do this multiplication as signed, then convert to the appropriate
2715 pointer type (actually unsigned integral). */
2717 intop = convert (result_type,
2718 build_binary_op (MULT_EXPR, intop,
2719 convert (TREE_TYPE (intop), size_exp), 1));
2721 /* Create the sum or difference. */
2723 result = build (resultcode, result_type, ptrop, intop);
2725 folded = fold (result);
2726 if (folded == result)
2727 TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop);
2731 /* Return a tree for the difference of pointers OP0 and OP1.
2732 The resulting tree has type int. */
2735 pointer_diff (op0, op1)
2736 register tree op0, op1;
2738 register tree result, folded;
2739 tree restype = ptrdiff_type_node;
2741 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2743 if (pedantic || warn_pointer_arith)
2745 if (TREE_CODE (target_type) == VOID_TYPE)
2746 pedwarn ("pointer of type `void *' used in subtraction");
2747 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2748 pedwarn ("pointer to a function used in subtraction");
2751 /* First do the subtraction as integers;
2752 then drop through to build the divide operator.
2753 Do not do default conversions on the minus operator
2754 in case restype is a short type. */
2756 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2757 convert (restype, op1), 0);
2758 /* This generates an error if op1 is pointer to incomplete type. */
2759 if (TYPE_SIZE (TREE_TYPE (TREE_TYPE (op1))) == 0)
2760 error ("arithmetic on pointer to an incomplete type");
2762 /* This generates an error if op0 is pointer to incomplete type. */
2763 op1 = c_size_in_bytes (target_type);
2765 /* Divide by the size, in easiest possible way. */
2767 result = build (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2769 folded = fold (result);
2770 if (folded == result)
2771 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2775 /* Construct and perhaps optimize a tree representation
2776 for a unary operation. CODE, a tree_code, specifies the operation
2777 and XARG is the operand. NOCONVERT nonzero suppresses
2778 the default promotions (such as from short to int). */
2781 build_unary_op (code, xarg, noconvert)
2782 enum tree_code code;
2786 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2787 register tree arg = xarg;
2788 register tree argtype = 0;
2789 register enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2790 char *errstring = NULL;
2793 if (typecode == ERROR_MARK)
2794 return error_mark_node;
2795 if (typecode == ENUMERAL_TYPE)
2796 typecode = INTEGER_TYPE;
2801 /* This is used for unary plus, because a CONVERT_EXPR
2802 is enough to prevent anybody from looking inside for
2803 associativity, but won't generate any code. */
2804 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2805 || typecode == COMPLEX_TYPE))
2806 errstring = "wrong type argument to unary plus";
2807 else if (!noconvert)
2808 arg = default_conversion (arg);
2812 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2813 || typecode == COMPLEX_TYPE))
2814 errstring = "wrong type argument to unary minus";
2815 else if (!noconvert)
2816 arg = default_conversion (arg);
2820 if (typecode == COMPLEX_TYPE)
2824 arg = default_conversion (arg);
2826 else if (typecode != INTEGER_TYPE)
2827 errstring = "wrong type argument to bit-complement";
2828 else if (!noconvert)
2829 arg = default_conversion (arg);
2833 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2834 || typecode == COMPLEX_TYPE))
2835 errstring = "wrong type argument to abs";
2836 else if (!noconvert)
2837 arg = default_conversion (arg);
2841 /* Conjugating a real value is a no-op, but allow it anyway. */
2842 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2843 || typecode == COMPLEX_TYPE))
2844 errstring = "wrong type argument to conjugation";
2845 else if (!noconvert)
2846 arg = default_conversion (arg);
2849 case TRUTH_NOT_EXPR:
2850 if (typecode != INTEGER_TYPE
2851 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2852 && typecode != COMPLEX_TYPE
2853 /* These will convert to a pointer. */
2854 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2856 errstring = "wrong type argument to unary exclamation mark";
2859 arg = truthvalue_conversion (arg);
2860 return invert_truthvalue (arg);
2866 if (TREE_CODE (arg) == COMPLEX_CST)
2867 return TREE_REALPART (arg);
2868 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2869 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2874 if (TREE_CODE (arg) == COMPLEX_CST)
2875 return TREE_IMAGPART (arg);
2876 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2877 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2879 return convert (TREE_TYPE (arg), integer_zero_node);
2881 case PREINCREMENT_EXPR:
2882 case POSTINCREMENT_EXPR:
2883 case PREDECREMENT_EXPR:
2884 case POSTDECREMENT_EXPR:
2885 /* Handle complex lvalues (when permitted)
2886 by reduction to simpler cases. */
2888 val = unary_complex_lvalue (code, arg);
2892 /* Increment or decrement the real part of the value,
2893 and don't change the imaginary part. */
2894 if (typecode == COMPLEX_TYPE)
2898 arg = stabilize_reference (arg);
2899 real = build_unary_op (REALPART_EXPR, arg, 1);
2900 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2901 return build (COMPLEX_EXPR, TREE_TYPE (arg),
2902 build_unary_op (code, real, 1), imag);
2905 /* Report invalid types. */
2907 if (typecode != POINTER_TYPE
2908 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2910 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2911 errstring ="wrong type argument to increment";
2913 errstring ="wrong type argument to decrement";
2919 tree result_type = TREE_TYPE (arg);
2921 arg = get_unwidened (arg, 0);
2922 argtype = TREE_TYPE (arg);
2924 /* Compute the increment. */
2926 if (typecode == POINTER_TYPE)
2928 /* If pointer target is an undefined struct,
2929 we just cannot know how to do the arithmetic. */
2930 if (TYPE_SIZE (TREE_TYPE (result_type)) == 0)
2931 error ("%s of pointer to unknown structure",
2932 ((code == PREINCREMENT_EXPR
2933 || code == POSTINCREMENT_EXPR)
2934 ? "increment" : "decrement"));
2935 else if ((pedantic || warn_pointer_arith)
2936 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2937 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2938 pedwarn ("wrong type argument to %s",
2939 ((code == PREINCREMENT_EXPR
2940 || code == POSTINCREMENT_EXPR)
2941 ? "increment" : "decrement"));
2942 inc = c_size_in_bytes (TREE_TYPE (result_type));
2945 inc = integer_one_node;
2947 inc = convert (argtype, inc);
2949 /* Handle incrementing a cast-expression. */
2952 switch (TREE_CODE (arg))
2957 case FIX_TRUNC_EXPR:
2958 case FIX_FLOOR_EXPR:
2959 case FIX_ROUND_EXPR:
2961 pedantic_lvalue_warning (CONVERT_EXPR);
2962 /* If the real type has the same machine representation
2963 as the type it is cast to, we can make better output
2964 by adding directly to the inside of the cast. */
2965 if ((TREE_CODE (TREE_TYPE (arg))
2966 == TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0))))
2967 && (TYPE_MODE (TREE_TYPE (arg))
2968 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (arg, 0)))))
2969 arg = TREE_OPERAND (arg, 0);
2972 tree incremented, modify, value;
2973 arg = stabilize_reference (arg);
2974 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
2977 value = save_expr (arg);
2978 incremented = build (((code == PREINCREMENT_EXPR
2979 || code == POSTINCREMENT_EXPR)
2980 ? PLUS_EXPR : MINUS_EXPR),
2981 argtype, value, inc);
2982 TREE_SIDE_EFFECTS (incremented) = 1;
2983 modify = build_modify_expr (arg, NOP_EXPR, incremented);
2984 value = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
2985 TREE_USED (value) = 1;
2995 /* Complain about anything else that is not a true lvalue. */
2996 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2997 || code == POSTINCREMENT_EXPR)
2998 ? "increment" : "decrement")))
2999 return error_mark_node;
3001 /* Report a read-only lvalue. */
3002 if (TREE_READONLY (arg))
3003 readonly_warning (arg,
3004 ((code == PREINCREMENT_EXPR
3005 || code == POSTINCREMENT_EXPR)
3006 ? "increment" : "decrement"));
3008 val = build (code, TREE_TYPE (arg), arg, inc);
3009 TREE_SIDE_EFFECTS (val) = 1;
3010 val = convert (result_type, val);
3011 if (TREE_CODE (val) != code)
3012 TREE_NO_UNUSED_WARNING (val) = 1;
3017 /* Note that this operation never does default_conversion
3018 regardless of NOCONVERT. */
3020 /* Let &* cancel out to simplify resulting code. */
3021 if (TREE_CODE (arg) == INDIRECT_REF)
3023 /* Don't let this be an lvalue. */
3024 if (lvalue_p (TREE_OPERAND (arg, 0)))
3025 return non_lvalue (TREE_OPERAND (arg, 0));
3026 return TREE_OPERAND (arg, 0);
3029 /* For &x[y], return x+y */
3030 if (TREE_CODE (arg) == ARRAY_REF)
3032 if (mark_addressable (TREE_OPERAND (arg, 0)) == 0)
3033 return error_mark_node;
3034 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
3035 TREE_OPERAND (arg, 1), 1);
3038 /* Handle complex lvalues (when permitted)
3039 by reduction to simpler cases. */
3040 val = unary_complex_lvalue (code, arg);
3044 #if 0 /* Turned off because inconsistent;
3045 float f; *&(int)f = 3.4 stores in int format
3046 whereas (int)f = 3.4 stores in float format. */
3047 /* Address of a cast is just a cast of the address
3048 of the operand of the cast. */
3049 switch (TREE_CODE (arg))
3054 case FIX_TRUNC_EXPR:
3055 case FIX_FLOOR_EXPR:
3056 case FIX_ROUND_EXPR:
3059 pedwarn ("ANSI C forbids the address of a cast expression");
3060 return convert (build_pointer_type (TREE_TYPE (arg)),
3061 build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0),
3066 /* Allow the address of a constructor if all the elements
3068 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_CONSTANT (arg))
3070 /* Anything not already handled and not a true memory reference
3072 else if (typecode != FUNCTION_TYPE && !lvalue_or_else (arg, "unary `&'"))
3073 return error_mark_node;
3075 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3076 argtype = TREE_TYPE (arg);
3077 /* If the lvalue is const or volatile,
3078 merge that into the type that the address will point to. */
3079 if (TREE_CODE_CLASS (TREE_CODE (arg)) == 'd'
3080 || TREE_CODE_CLASS (TREE_CODE (arg)) == 'r')
3082 if (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg))
3083 argtype = c_build_type_variant (argtype,
3084 TREE_READONLY (arg),
3085 TREE_THIS_VOLATILE (arg));
3088 argtype = build_pointer_type (argtype);
3090 if (mark_addressable (arg) == 0)
3091 return error_mark_node;
3096 if (TREE_CODE (arg) == COMPONENT_REF)
3098 tree field = TREE_OPERAND (arg, 1);
3100 addr = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
3102 if (DECL_C_BIT_FIELD (field))
3104 error ("attempt to take address of bit-field structure member `%s'",
3105 IDENTIFIER_POINTER (DECL_NAME (field)));
3106 return error_mark_node;
3109 addr = convert (argtype, addr);
3111 if (! integer_zerop (DECL_FIELD_BITPOS (field)))
3114 = size_binop (EASY_DIV_EXPR, DECL_FIELD_BITPOS (field),
3115 size_int (BITS_PER_UNIT));
3116 int flag = TREE_CONSTANT (addr);
3117 addr = fold (build (PLUS_EXPR, argtype,
3118 addr, convert (argtype, offset)));
3119 TREE_CONSTANT (addr) = flag;
3123 addr = build1 (code, argtype, arg);
3125 /* Address of a static or external variable or
3126 file-scope function counts as a constant. */
3128 && ! (TREE_CODE (arg) == FUNCTION_DECL
3129 && DECL_CONTEXT (arg) != 0))
3130 TREE_CONSTANT (addr) = 1;
3141 argtype = TREE_TYPE (arg);
3142 return fold (build1 (code, argtype, arg));
3146 return error_mark_node;
3150 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3151 convert ARG with the same conversions in the same order
3152 and return the result. */
3155 convert_sequence (conversions, arg)
3159 switch (TREE_CODE (conversions))
3164 case FIX_TRUNC_EXPR:
3165 case FIX_FLOOR_EXPR:
3166 case FIX_ROUND_EXPR:
3168 return convert (TREE_TYPE (conversions),
3169 convert_sequence (TREE_OPERAND (conversions, 0),
3178 /* Return nonzero if REF is an lvalue valid for this language.
3179 Lvalues can be assigned, unless their type has TYPE_READONLY.
3180 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3186 register enum tree_code code = TREE_CODE (ref);
3193 return lvalue_p (TREE_OPERAND (ref, 0));
3204 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3205 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3209 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3216 /* Return nonzero if REF is an lvalue valid for this language;
3217 otherwise, print an error message and return zero. */
3220 lvalue_or_else (ref, string)
3224 int win = lvalue_p (ref);
3226 error ("invalid lvalue in %s", string);
3230 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3231 for certain kinds of expressions which are not really lvalues
3232 but which we can accept as lvalues.
3234 If ARG is not a kind of expression we can handle, return zero. */
3237 unary_complex_lvalue (code, arg)
3238 enum tree_code code;
3241 /* Handle (a, b) used as an "lvalue". */
3242 if (TREE_CODE (arg) == COMPOUND_EXPR)
3244 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
3246 /* If this returns a function type, it isn't really being used as
3247 an lvalue, so don't issue a warning about it. */
3248 if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE)
3249 pedantic_lvalue_warning (COMPOUND_EXPR);
3251 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
3252 TREE_OPERAND (arg, 0), real_result);
3255 /* Handle (a ? b : c) used as an "lvalue". */
3256 if (TREE_CODE (arg) == COND_EXPR)
3258 pedantic_lvalue_warning (COND_EXPR);
3259 if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE)
3260 pedantic_lvalue_warning (COMPOUND_EXPR);
3262 return (build_conditional_expr
3263 (TREE_OPERAND (arg, 0),
3264 build_unary_op (code, TREE_OPERAND (arg, 1), 0),
3265 build_unary_op (code, TREE_OPERAND (arg, 2), 0)));
3271 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3272 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3275 pedantic_lvalue_warning (code)
3276 enum tree_code code;
3279 pedwarn ("ANSI C forbids use of %s expressions as lvalues",
3280 code == COND_EXPR ? "conditional"
3281 : code == COMPOUND_EXPR ? "compound" : "cast");
3284 /* Warn about storing in something that is `const'. */
3287 readonly_warning (arg, string)
3292 strcpy (buf, string);
3294 /* Forbid assignments to iterators. */
3295 if (TREE_CODE (arg) == VAR_DECL && ITERATOR_P (arg))
3297 strcat (buf, " of iterator `%s'");
3298 pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (arg)));
3301 if (TREE_CODE (arg) == COMPONENT_REF)
3303 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3304 readonly_warning (TREE_OPERAND (arg, 0), string);
3307 strcat (buf, " of read-only member `%s'");
3308 pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1))));
3311 else if (TREE_CODE (arg) == VAR_DECL)
3313 strcat (buf, " of read-only variable `%s'");
3314 pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (arg)));
3318 pedwarn ("%s of read-only location", buf);
3322 /* Mark EXP saying that we need to be able to take the
3323 address of it; it should not be allocated in a register.
3324 Value is 1 if successful. */
3327 mark_addressable (exp)
3330 register tree x = exp;
3332 switch (TREE_CODE (x))
3335 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3337 error ("cannot take address of bitfield `%s'",
3338 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (x, 1))));
3342 /* ... fall through ... */
3348 x = TREE_OPERAND (x, 0);
3352 TREE_ADDRESSABLE (x) = 1;
3359 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
3360 && DECL_NONLOCAL (x))
3362 if (TREE_PUBLIC (x))
3364 error ("global register variable `%s' used in nested function",
3365 IDENTIFIER_POINTER (DECL_NAME (x)));
3368 pedwarn ("register variable `%s' used in nested function",
3369 IDENTIFIER_POINTER (DECL_NAME (x)));
3371 else if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x))
3373 if (TREE_PUBLIC (x))
3375 error ("address of global register variable `%s' requested",
3376 IDENTIFIER_POINTER (DECL_NAME (x)));
3380 /* If we are making this addressable due to its having
3381 volatile components, give a different error message. Also
3382 handle the case of an unnamed parameter by not trying
3383 to give the name. */
3385 else if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (x)))
3387 error ("cannot put object with volatile field into register");
3391 pedwarn ("address of register variable `%s' requested",
3392 IDENTIFIER_POINTER (DECL_NAME (x)));
3394 put_var_into_stack (x);
3398 TREE_ADDRESSABLE (x) = 1;
3399 #if 0 /* poplevel deals with this now. */
3400 if (DECL_CONTEXT (x) == 0)
3401 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
3409 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3412 build_conditional_expr (ifexp, op1, op2)
3413 tree ifexp, op1, op2;
3415 register tree type1;
3416 register tree type2;
3417 register enum tree_code code1;
3418 register enum tree_code code2;
3419 register tree result_type = NULL;
3420 tree orig_op1 = op1, orig_op2 = op2;
3422 ifexp = truthvalue_conversion (default_conversion (ifexp));
3424 #if 0 /* Produces wrong result if within sizeof. */
3425 /* Don't promote the operands separately if they promote
3426 the same way. Return the unpromoted type and let the combined
3427 value get promoted if necessary. */
3429 if (TREE_TYPE (op1) == TREE_TYPE (op2)
3430 && TREE_CODE (TREE_TYPE (op1)) != ARRAY_TYPE
3431 && TREE_CODE (TREE_TYPE (op1)) != ENUMERAL_TYPE
3432 && TREE_CODE (TREE_TYPE (op1)) != FUNCTION_TYPE)
3434 if (TREE_CODE (ifexp) == INTEGER_CST)
3435 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3437 return fold (build (COND_EXPR, TREE_TYPE (op1), ifexp, op1, op2));
3441 /* Promote both alternatives. */
3443 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3444 op1 = default_conversion (op1);
3445 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3446 op2 = default_conversion (op2);
3448 if (TREE_CODE (ifexp) == ERROR_MARK
3449 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3450 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3451 return error_mark_node;
3453 type1 = TREE_TYPE (op1);
3454 code1 = TREE_CODE (type1);
3455 type2 = TREE_TYPE (op2);
3456 code2 = TREE_CODE (type2);
3458 /* Quickly detect the usual case where op1 and op2 have the same type
3460 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3463 result_type = type1;
3465 result_type = TYPE_MAIN_VARIANT (type1);
3467 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE)
3468 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE))
3470 result_type = common_type (type1, type2);
3472 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3474 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3475 pedwarn ("ANSI C forbids conditional expr with only one void side");
3476 result_type = void_type_node;
3478 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3480 if (comp_target_types (type1, type2))
3481 result_type = common_type (type1, type2);
3482 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
3483 && TREE_CODE (orig_op1) != NOP_EXPR)
3484 result_type = qualify_type (type2, type1);
3485 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
3486 && TREE_CODE (orig_op2) != NOP_EXPR)
3487 result_type = qualify_type (type1, type2);
3488 else if (TYPE_MAIN_VARIANT (TREE_TYPE (type1)) == void_type_node)
3490 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3491 pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer");
3492 result_type = qualify_type (type1, type2);
3494 else if (TYPE_MAIN_VARIANT (TREE_TYPE (type2)) == void_type_node)
3496 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3497 pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer");
3498 result_type = qualify_type (type2, type1);
3502 pedwarn ("pointer type mismatch in conditional expression");
3503 result_type = build_pointer_type (void_type_node);
3506 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3508 if (! integer_zerop (op2))
3509 pedwarn ("pointer/integer type mismatch in conditional expression");
3512 op2 = null_pointer_node;
3513 #if 0 /* The spec seems to say this is permitted. */
3514 if (pedantic && TREE_CODE (type1) == FUNCTION_TYPE)
3515 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3518 result_type = type1;
3520 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3522 if (!integer_zerop (op1))
3523 pedwarn ("pointer/integer type mismatch in conditional expression");
3526 op1 = null_pointer_node;
3527 #if 0 /* The spec seems to say this is permitted. */
3528 if (pedantic && TREE_CODE (type2) == FUNCTION_TYPE)
3529 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3532 result_type = type2;
3537 if (flag_cond_mismatch)
3538 result_type = void_type_node;
3541 error ("type mismatch in conditional expression");
3542 return error_mark_node;
3546 /* Merge const and volatile flags of the incoming types. */
3548 = build_type_variant (result_type,
3549 TREE_READONLY (op1) || TREE_READONLY (op2),
3550 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3552 if (result_type != TREE_TYPE (op1))
3553 op1 = convert_and_check (result_type, op1);
3554 if (result_type != TREE_TYPE (op2))
3555 op2 = convert_and_check (result_type, op2);
3558 if (code1 == RECORD_TYPE || code1 == UNION_TYPE)
3560 result_type = TREE_TYPE (op1);
3561 if (TREE_CONSTANT (ifexp))
3562 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3564 if (TYPE_MODE (result_type) == BLKmode)
3566 register tree tempvar
3567 = build_decl (VAR_DECL, NULL_TREE, result_type);
3568 register tree xop1 = build_modify_expr (tempvar, op1);
3569 register tree xop2 = build_modify_expr (tempvar, op2);
3570 register tree result = fold (build (COND_EXPR, result_type,
3571 ifexp, xop1, xop2));
3573 layout_decl (tempvar, TYPE_ALIGN (result_type));
3574 /* No way to handle variable-sized objects here.
3575 I fear that the entire handling of BLKmode conditional exprs
3576 needs to be redone. */
3577 if (TREE_CODE (DECL_SIZE (tempvar)) != INTEGER_CST)
3580 = assign_stack_local (DECL_MODE (tempvar),
3581 (TREE_INT_CST_LOW (DECL_SIZE (tempvar))
3582 + BITS_PER_UNIT - 1)
3586 TREE_SIDE_EFFECTS (result)
3587 = TREE_SIDE_EFFECTS (ifexp) | TREE_SIDE_EFFECTS (op1)
3588 | TREE_SIDE_EFFECTS (op2);
3589 return build (COMPOUND_EXPR, result_type, result, tempvar);
3594 if (TREE_CODE (ifexp) == INTEGER_CST)
3595 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3597 return fold (build (COND_EXPR, result_type, ifexp, op1, op2));
3600 /* Given a list of expressions, return a compound expression
3601 that performs them all and returns the value of the last of them. */
3604 build_compound_expr (list)
3607 return internal_build_compound_expr (list, TRUE);
3611 internal_build_compound_expr (list, first_p)
3617 if (TREE_CHAIN (list) == 0)
3619 #if 0 /* If something inside inhibited lvalueness, we should not override. */
3620 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3622 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3623 if (TREE_CODE (list) == NON_LVALUE_EXPR)
3624 list = TREE_OPERAND (list, 0);
3627 /* Don't let (0, 0) be null pointer constant. */
3628 if (!first_p && integer_zerop (TREE_VALUE (list)))
3629 return non_lvalue (TREE_VALUE (list));
3630 return TREE_VALUE (list);
3633 if (TREE_CHAIN (list) != 0 && TREE_CHAIN (TREE_CHAIN (list)) == 0)
3635 /* Convert arrays to pointers when there really is a comma operator. */
3636 if (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (list)))) == ARRAY_TYPE)
3637 TREE_VALUE (TREE_CHAIN (list))
3638 = default_conversion (TREE_VALUE (TREE_CHAIN (list)));
3641 rest = internal_build_compound_expr (TREE_CHAIN (list), FALSE);
3643 if (! TREE_SIDE_EFFECTS (TREE_VALUE (list)))
3645 /* The left-hand operand of a comma expression is like an expression
3646 statement: with -W or -Wunused, we should warn if it doesn't have
3647 any side-effects, unless it was explicitly cast to (void). */
3648 if ((extra_warnings || warn_unused)
3649 && ! (TREE_CODE (TREE_VALUE (list)) == CONVERT_EXPR
3650 && TREE_TYPE (TREE_VALUE (list)) == void_type_node))
3651 warning ("left-hand operand of comma expression has no effect");
3653 /* When pedantic, a compound expression can be neither an lvalue
3654 nor an integer constant expression. */
3659 /* With -Wunused, we should also warn if the left-hand operand does have
3660 side-effects, but computes a value which is not used. For example, in
3661 `foo() + bar(), baz()' the result of the `+' operator is not used,
3662 so we should issue a warning. */
3663 else if (warn_unused)
3664 warn_if_unused_value (TREE_VALUE (list));
3666 return build (COMPOUND_EXPR, TREE_TYPE (rest), TREE_VALUE (list), rest);
3669 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3672 build_c_cast (type, expr)
3676 register tree value = expr;
3678 if (type == error_mark_node || expr == error_mark_node)
3679 return error_mark_node;
3680 type = TYPE_MAIN_VARIANT (type);
3683 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3684 if (TREE_CODE (value) == NON_LVALUE_EXPR)
3685 value = TREE_OPERAND (value, 0);
3688 if (TREE_CODE (type) == ARRAY_TYPE)
3690 error ("cast specifies array type");
3691 return error_mark_node;
3694 if (TREE_CODE (type) == FUNCTION_TYPE)
3696 error ("cast specifies function type");
3697 return error_mark_node;
3700 if (type == TREE_TYPE (value))
3704 if (TREE_CODE (type) == RECORD_TYPE
3705 || TREE_CODE (type) == UNION_TYPE)
3706 pedwarn ("ANSI C forbids casting nonscalar to the same type");
3709 else if (TREE_CODE (type) == UNION_TYPE)
3712 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
3713 || TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE)
3714 value = default_conversion (value);
3716 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3717 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3718 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3727 pedwarn ("ANSI C forbids casts to union type");
3728 if (TYPE_NAME (type) != 0)
3730 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
3731 name = IDENTIFIER_POINTER (TYPE_NAME (type));
3733 name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));
3737 t = digest_init (type, build (CONSTRUCTOR, type, NULL_TREE,
3738 build_tree_list (field, value)),
3740 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3743 error ("cast to union type from type not present in union");
3744 return error_mark_node;
3750 /* If casting to void, avoid the error that would come
3751 from default_conversion in the case of a non-lvalue array. */
3752 if (type == void_type_node)
3753 return build1 (CONVERT_EXPR, type, value);
3755 /* Convert functions and arrays to pointers,
3756 but don't convert any other types. */
3757 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
3758 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE)
3759 value = default_conversion (value);
3760 otype = TREE_TYPE (value);
3762 /* Optionally warn about potentially worrisome casts. */
3765 && TREE_CODE (type) == POINTER_TYPE
3766 && TREE_CODE (otype) == POINTER_TYPE)
3768 if (TYPE_VOLATILE (TREE_TYPE (otype))
3769 && ! TYPE_VOLATILE (TREE_TYPE (type)))
3770 pedwarn ("cast discards `volatile' from pointer target type");
3771 if (TYPE_READONLY (TREE_TYPE (otype))
3772 && ! TYPE_READONLY (TREE_TYPE (type)))
3773 pedwarn ("cast discards `const' from pointer target type");
3776 /* Warn about possible alignment problems. */
3777 if (STRICT_ALIGNMENT && warn_cast_align
3778 && TREE_CODE (type) == POINTER_TYPE
3779 && TREE_CODE (otype) == POINTER_TYPE
3780 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3781 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3782 /* Don't warn about opaque types, where the actual alignment
3783 restriction is unknown. */
3784 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3785 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3786 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3787 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3788 warning ("cast increases required alignment of target type");
3790 if (TREE_CODE (type) == INTEGER_TYPE
3791 && TREE_CODE (otype) == POINTER_TYPE
3792 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3793 && !TREE_CONSTANT (value))
3794 warning ("cast from pointer to integer of different size");
3796 if (warn_bad_function_cast
3797 && TREE_CODE (value) == CALL_EXPR
3798 && TREE_CODE (type) != TREE_CODE (otype))
3799 warning ("cast does not match function type");
3801 if (TREE_CODE (type) == POINTER_TYPE
3802 && TREE_CODE (otype) == INTEGER_TYPE
3803 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3805 /* Don't warn about converting 0 to pointer,
3806 provided the 0 was explicit--not cast or made by folding. */
3807 && !(TREE_CODE (value) == INTEGER_CST && integer_zerop (value))
3809 /* Don't warn about converting any constant. */
3810 && !TREE_CONSTANT (value))
3811 warning ("cast to pointer from integer of different size");
3814 value = convert (type, value);
3816 /* Ignore any integer overflow caused by the cast. */
3817 if (TREE_CODE (value) == INTEGER_CST)
3819 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3820 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3824 /* Pedantically, don't ley (void *) (FOO *) 0 be a null pointer constant. */
3825 if (pedantic && TREE_CODE (value) == INTEGER_CST
3826 && TREE_CODE (expr) == INTEGER_CST
3827 && TREE_CODE (TREE_TYPE (expr)) != INTEGER_TYPE)
3828 value = non_lvalue (value);
3830 /* If pedantic, don't let a cast be an lvalue. */
3831 if (value == expr && pedantic)
3832 value = non_lvalue (value);
3837 /* Build an assignment expression of lvalue LHS from value RHS.
3838 MODIFYCODE is the code for a binary operator that we use
3839 to combine the old value of LHS with RHS to get the new value.
3840 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3843 build_modify_expr (lhs, modifycode, rhs)
3845 enum tree_code modifycode;
3847 register tree result;
3849 tree lhstype = TREE_TYPE (lhs);
3850 tree olhstype = lhstype;
3852 /* Types that aren't fully specified cannot be used in assignments. */
3853 lhs = require_complete_type (lhs);
3855 /* Avoid duplicate error messages from operands that had errors. */
3856 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3857 return error_mark_node;
3859 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3860 /* Do not use STRIP_NOPS here. We do not want an enumerator
3861 whose value is 0 to count as a null pointer constant. */
3862 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3863 rhs = TREE_OPERAND (rhs, 0);
3867 /* Handle control structure constructs used as "lvalues". */
3869 switch (TREE_CODE (lhs))
3871 /* Handle (a, b) used as an "lvalue". */
3873 pedantic_lvalue_warning (COMPOUND_EXPR);
3874 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
3876 if (TREE_CODE (newrhs) == ERROR_MARK)
3877 return error_mark_node;
3878 return build (COMPOUND_EXPR, lhstype,
3879 TREE_OPERAND (lhs, 0), newrhs);
3881 /* Handle (a ? b : c) used as an "lvalue". */
3883 pedantic_lvalue_warning (COND_EXPR);
3884 rhs = save_expr (rhs);
3886 /* Produce (a ? (b = rhs) : (c = rhs))
3887 except that the RHS goes through a save-expr
3888 so the code to compute it is only emitted once. */
3890 = build_conditional_expr (TREE_OPERAND (lhs, 0),
3891 build_modify_expr (TREE_OPERAND (lhs, 1),
3893 build_modify_expr (TREE_OPERAND (lhs, 2),
3895 if (TREE_CODE (cond) == ERROR_MARK)
3897 /* Make sure the code to compute the rhs comes out
3898 before the split. */
3899 return build (COMPOUND_EXPR, TREE_TYPE (lhs),
3900 /* But cast it to void to avoid an "unused" error. */
3901 convert (void_type_node, rhs), cond);
3907 /* If a binary op has been requested, combine the old LHS value with the RHS
3908 producing the value we should actually store into the LHS. */
3910 if (modifycode != NOP_EXPR)
3912 lhs = stabilize_reference (lhs);
3913 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3916 /* Handle a cast used as an "lvalue".
3917 We have already performed any binary operator using the value as cast.
3918 Now convert the result to the cast type of the lhs,
3919 and then true type of the lhs and store it there;
3920 then convert result back to the cast type to be the value
3921 of the assignment. */
3923 switch (TREE_CODE (lhs))
3928 case FIX_TRUNC_EXPR:
3929 case FIX_FLOOR_EXPR:
3930 case FIX_ROUND_EXPR:
3932 if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
3933 || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE)
3934 newrhs = default_conversion (newrhs);
3936 tree inner_lhs = TREE_OPERAND (lhs, 0);
3938 result = build_modify_expr (inner_lhs, NOP_EXPR,
3939 convert (TREE_TYPE (inner_lhs),
3940 convert (lhstype, newrhs)));
3941 if (TREE_CODE (result) == ERROR_MARK)
3943 pedantic_lvalue_warning (CONVERT_EXPR);
3944 return convert (TREE_TYPE (lhs), result);
3951 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3952 Reject anything strange now. */
3954 if (!lvalue_or_else (lhs, "assignment"))
3955 return error_mark_node;
3957 /* Warn about storing in something that is `const'. */
3959 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3960 || ((TREE_CODE (lhstype) == RECORD_TYPE
3961 || TREE_CODE (lhstype) == UNION_TYPE)
3962 && C_TYPE_FIELDS_READONLY (lhstype)))
3963 readonly_warning (lhs, "assignment");
3965 /* If storing into a structure or union member,
3966 it has probably been given type `int'.
3967 Compute the type that would go with
3968 the actual amount of storage the member occupies. */
3970 if (TREE_CODE (lhs) == COMPONENT_REF
3971 && (TREE_CODE (lhstype) == INTEGER_TYPE
3972 || TREE_CODE (lhstype) == REAL_TYPE
3973 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3974 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3976 /* If storing in a field that is in actuality a short or narrower than one,
3977 we must store in the field in its actual type. */
3979 if (lhstype != TREE_TYPE (lhs))
3981 lhs = copy_node (lhs);
3982 TREE_TYPE (lhs) = lhstype;
3985 /* Convert new value to destination type. */
3987 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
3988 NULL_TREE, NULL_TREE, 0);
3989 if (TREE_CODE (newrhs) == ERROR_MARK)
3990 return error_mark_node;
3992 result = build (MODIFY_EXPR, lhstype, lhs, newrhs);
3993 TREE_SIDE_EFFECTS (result) = 1;
3995 /* If we got the LHS in a different type for storing in,
3996 convert the result back to the nominal type of LHS
3997 so that the value we return always has the same type
3998 as the LHS argument. */
4000 if (olhstype == TREE_TYPE (result))
4002 return convert_for_assignment (olhstype, result, "assignment",
4003 NULL_TREE, NULL_TREE, 0);
4006 /* Convert value RHS to type TYPE as preparation for an assignment
4007 to an lvalue of type TYPE.
4008 The real work of conversion is done by `convert'.
4009 The purpose of this function is to generate error messages
4010 for assignments that are not allowed in C.
4011 ERRTYPE is a string to use in error messages:
4012 "assignment", "return", etc. If it is null, this is parameter passing
4013 for a function call (and different error messages are output). Otherwise,
4014 it may be a name stored in the spelling stack and interpreted by
4017 FUNNAME is the name of the function being called,
4018 as an IDENTIFIER_NODE, or null.
4019 PARMNUM is the number of the argument, for printing in error messages. */
4022 convert_for_assignment (type, rhs, errtype, fundecl, funname, parmnum)
4025 tree fundecl, funname;
4028 register enum tree_code codel = TREE_CODE (type);
4029 register tree rhstype;
4030 register enum tree_code coder;
4032 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4033 /* Do not use STRIP_NOPS here. We do not want an enumerator
4034 whose value is 0 to count as a null pointer constant. */
4035 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
4036 rhs = TREE_OPERAND (rhs, 0);
4038 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
4039 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
4040 rhs = default_conversion (rhs);
4041 else if (optimize && TREE_CODE (rhs) == VAR_DECL)
4042 rhs = decl_constant_value (rhs);
4044 rhstype = TREE_TYPE (rhs);
4045 coder = TREE_CODE (rhstype);
4047 if (coder == ERROR_MARK)
4048 return error_mark_node;
4050 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
4052 overflow_warning (rhs);
4053 /* Check for Objective-C protocols. This will issue a warning if
4054 there are protocol violations. No need to use the return value. */
4055 maybe_objc_comptypes (type, rhstype, 0);
4059 if (coder == VOID_TYPE)
4061 error ("void value not ignored as it ought to be");
4062 return error_mark_node;
4064 /* Arithmetic types all interconvert, and enum is treated like int. */
4065 if ((codel == INTEGER_TYPE || codel == REAL_TYPE || codel == ENUMERAL_TYPE
4066 || codel == COMPLEX_TYPE)
4067 && (coder == INTEGER_TYPE || coder == REAL_TYPE || coder == ENUMERAL_TYPE
4068 || coder == COMPLEX_TYPE))
4069 return convert_and_check (type, rhs);
4071 /* Conversion to a transparent union from its member types.
4072 This applies only to function arguments. */
4073 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type) && ! errtype)
4076 tree marginal_memb_type = 0;
4078 for (memb_types = TYPE_FIELDS (type); memb_types;
4079 memb_types = TREE_CHAIN (memb_types))
4081 tree memb_type = TREE_TYPE (memb_types);
4083 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
4084 TYPE_MAIN_VARIANT (rhstype)))
4087 if (TREE_CODE (memb_type) != POINTER_TYPE)
4090 if (coder == POINTER_TYPE)
4092 register tree ttl = TREE_TYPE (memb_type);
4093 register tree ttr = TREE_TYPE (rhstype);
4095 /* Any non-function converts to a [const][volatile] void *
4096 and vice versa; otherwise, targets must be the same.
4097 Meanwhile, the lhs target must have all the qualifiers of
4099 if (TYPE_MAIN_VARIANT (ttl) == void_type_node
4100 || TYPE_MAIN_VARIANT (ttr) == void_type_node
4101 || comp_target_types (memb_type, rhstype))
4103 /* If this type won't generate any warnings, use it. */
4104 if ((TREE_CODE (ttr) == FUNCTION_TYPE
4105 && TREE_CODE (ttl) == FUNCTION_TYPE)
4106 ? ((! TYPE_READONLY (ttl) | TYPE_READONLY (ttr))
4107 & (! TYPE_VOLATILE (ttl) | TYPE_VOLATILE (ttr)))
4108 : ((TYPE_READONLY (ttl) | ! TYPE_READONLY (ttr))
4109 & (TYPE_VOLATILE (ttl) | ! TYPE_VOLATILE (ttr))))
4112 /* Keep looking for a better type, but remember this one. */
4113 if (! marginal_memb_type)
4114 marginal_memb_type = memb_type;
4118 /* Can convert integer zero to any pointer type. */
4119 if (integer_zerop (rhs)
4120 || (TREE_CODE (rhs) == NOP_EXPR
4121 && integer_zerop (TREE_OPERAND (rhs, 0))))
4123 rhs = null_pointer_node;
4128 if (memb_types || marginal_memb_type)
4132 /* We have only a marginally acceptable member type;
4133 it needs a warning. */
4134 register tree ttl = TREE_TYPE (marginal_memb_type);
4135 register tree ttr = TREE_TYPE (rhstype);
4137 /* Const and volatile mean something different for function
4138 types, so the usual warnings are not appropriate. */
4139 if (TREE_CODE (ttr) == FUNCTION_TYPE
4140 && TREE_CODE (ttl) == FUNCTION_TYPE)
4142 /* Because const and volatile on functions are
4143 restrictions that say the function will not do
4144 certain things, it is okay to use a const or volatile
4145 function where an ordinary one is wanted, but not
4147 if (TYPE_READONLY (ttl) && ! TYPE_READONLY (ttr))
4148 warn_for_assignment ("%s makes `const *' function pointer from non-const",
4149 get_spelling (errtype), funname,
4151 if (TYPE_VOLATILE (ttl) && ! TYPE_VOLATILE (ttr))
4152 warn_for_assignment ("%s makes `volatile *' function pointer from non-volatile",
4153 get_spelling (errtype), funname,
4158 if (! TYPE_READONLY (ttl) && TYPE_READONLY (ttr))
4159 warn_for_assignment ("%s discards `const' from pointer target type",
4160 get_spelling (errtype), funname,
4162 if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr))
4163 warn_for_assignment ("%s discards `volatile' from pointer target type",
4164 get_spelling (errtype), funname,
4169 if (pedantic && ! DECL_IN_SYSTEM_HEADER (fundecl))
4170 pedwarn ("ANSI C prohibits argument conversion to union type");
4172 return build1 (NOP_EXPR, type, rhs);
4176 /* Conversions among pointers */
4177 else if (codel == POINTER_TYPE && coder == POINTER_TYPE)
4179 register tree ttl = TREE_TYPE (type);
4180 register tree ttr = TREE_TYPE (rhstype);
4182 /* Any non-function converts to a [const][volatile] void *
4183 and vice versa; otherwise, targets must be the same.
4184 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4185 if (TYPE_MAIN_VARIANT (ttl) == void_type_node
4186 || TYPE_MAIN_VARIANT (ttr) == void_type_node
4187 || comp_target_types (type, rhstype)
4188 || (unsigned_type (TYPE_MAIN_VARIANT (ttl))
4189 == unsigned_type (TYPE_MAIN_VARIANT (ttr))))
4192 && ((TYPE_MAIN_VARIANT (ttl) == void_type_node
4193 && TREE_CODE (ttr) == FUNCTION_TYPE)
4195 (TYPE_MAIN_VARIANT (ttr) == void_type_node
4196 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4197 which are not ANSI null ptr constants. */
4198 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
4199 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4200 warn_for_assignment ("ANSI forbids %s between function pointer and `void *'",
4201 get_spelling (errtype), funname, parmnum);
4202 /* Const and volatile mean something different for function types,
4203 so the usual warnings are not appropriate. */
4204 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4205 && TREE_CODE (ttl) != FUNCTION_TYPE)
4207 if (! TYPE_READONLY (ttl) && TYPE_READONLY (ttr))
4208 warn_for_assignment ("%s discards `const' from pointer target type",
4209 get_spelling (errtype), funname, parmnum);
4210 else if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr))
4211 warn_for_assignment ("%s discards `volatile' from pointer target type",
4212 get_spelling (errtype), funname, parmnum);
4213 /* If this is not a case of ignoring a mismatch in signedness,
4215 else if (TYPE_MAIN_VARIANT (ttl) == void_type_node
4216 || TYPE_MAIN_VARIANT (ttr) == void_type_node
4217 || comp_target_types (type, rhstype))
4219 /* If there is a mismatch, do warn. */
4221 warn_for_assignment ("pointer targets in %s differ in signedness",
4222 get_spelling (errtype), funname, parmnum);
4224 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4225 && TREE_CODE (ttr) == FUNCTION_TYPE)
4227 /* Because const and volatile on functions are restrictions
4228 that say the function will not do certain things,
4229 it is okay to use a const or volatile function
4230 where an ordinary one is wanted, but not vice-versa. */
4231 if (TYPE_READONLY (ttl) && ! TYPE_READONLY (ttr))
4232 warn_for_assignment ("%s makes `const *' function pointer from non-const",
4233 get_spelling (errtype), funname, parmnum);
4234 if (TYPE_VOLATILE (ttl) && ! TYPE_VOLATILE (ttr))
4235 warn_for_assignment ("%s makes `volatile *' function pointer from non-volatile",
4236 get_spelling (errtype), funname, parmnum);
4240 warn_for_assignment ("%s from incompatible pointer type",
4241 get_spelling (errtype), funname, parmnum);
4242 return convert (type, rhs);
4244 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4246 /* An explicit constant 0 can convert to a pointer,
4247 or one that results from arithmetic, even including
4248 a cast to integer type. */
4249 if (! (TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
4251 ! (TREE_CODE (rhs) == NOP_EXPR
4252 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
4253 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
4254 && integer_zerop (TREE_OPERAND (rhs, 0))))
4256 warn_for_assignment ("%s makes pointer from integer without a cast",
4257 get_spelling (errtype), funname, parmnum);
4258 return convert (type, rhs);
4260 return null_pointer_node;
4262 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4264 warn_for_assignment ("%s makes integer from pointer without a cast",
4265 get_spelling (errtype), funname, parmnum);
4266 return convert (type, rhs);
4273 tree selector = maybe_building_objc_message_expr ();
4275 if (selector && parmnum > 2)
4276 error ("incompatible type for argument %d of `%s'",
4277 parmnum - 2, IDENTIFIER_POINTER (selector));
4279 error ("incompatible type for argument %d of `%s'",
4280 parmnum, IDENTIFIER_POINTER (funname));
4283 error ("incompatible type for argument %d of indirect function call",
4287 error ("incompatible types in %s", get_spelling (errtype));
4289 return error_mark_node;
4292 /* Print a warning using MSG.
4293 It gets OPNAME as its one parameter.
4294 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4295 FUNCTION and ARGNUM are handled specially if we are building an
4296 Objective-C selector. */
4299 warn_for_assignment (msg, opname, function, argnum)
4305 static char argstring[] = "passing arg %d of `%s'";
4306 static char argnofun[] = "passing arg %d";
4310 tree selector = maybe_building_objc_message_expr ();
4312 if (selector && argnum > 2)
4314 function = selector;
4319 /* Function name is known; supply it. */
4320 opname = (char *) alloca (IDENTIFIER_LENGTH (function)
4321 + sizeof (argstring) + 25 /*%d*/ + 1);
4322 sprintf (opname, argstring, argnum, IDENTIFIER_POINTER (function));
4326 /* Function name unknown (call through ptr); just give arg number. */
4327 opname = (char *) alloca (sizeof (argnofun) + 25 /*%d*/ + 1);
4328 sprintf (opname, argnofun, argnum);
4331 pedwarn (msg, opname);
4334 /* Return nonzero if VALUE is a valid constant-valued expression
4335 for use in initializing a static variable; one that can be an
4336 element of a "constant" initializer.
4338 Return null_pointer_node if the value is absolute;
4339 if it is relocatable, return the variable that determines the relocation.
4340 We assume that VALUE has been folded as much as possible;
4341 therefore, we do not need to check for such things as
4342 arithmetic-combinations of integers. */
4345 initializer_constant_valid_p (value, endtype)
4349 switch (TREE_CODE (value))
4352 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
4353 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE)
4354 && TREE_CONSTANT (value)
4355 && CONSTRUCTOR_ELTS (value))
4357 initializer_constant_valid_p (TREE_VALUE (CONSTRUCTOR_ELTS (value)),
4360 return TREE_STATIC (value) ? null_pointer_node : 0;
4366 return null_pointer_node;
4369 return TREE_OPERAND (value, 0);
4371 case NON_LVALUE_EXPR:
4372 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4376 /* Allow conversions between pointer types. */
4377 if (TREE_CODE (TREE_TYPE (value)) == POINTER_TYPE
4378 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == POINTER_TYPE)
4379 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4381 /* Allow conversions between real types. */
4382 if (TREE_CODE (TREE_TYPE (value)) == REAL_TYPE
4383 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == REAL_TYPE)
4384 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4386 /* Allow length-preserving conversions between integer types. */
4387 if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
4388 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE
4389 && (TYPE_PRECISION (TREE_TYPE (value))
4390 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
4391 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4393 /* Allow conversions between other integer types only if
4395 if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
4396 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE)
4398 tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0),
4400 if (inner == null_pointer_node)
4401 return null_pointer_node;
4405 /* Allow (int) &foo provided int is as wide as a pointer. */
4406 if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
4407 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == POINTER_TYPE
4408 && (TYPE_PRECISION (TREE_TYPE (value))
4409 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
4410 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
4413 /* Likewise conversions from int to pointers. */
4414 if (TREE_CODE (TREE_TYPE (value)) == POINTER_TYPE
4415 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE
4416 && (TYPE_PRECISION (TREE_TYPE (value))
4417 <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
4418 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
4421 /* Allow conversions to union types if the value inside is okay. */
4422 if (TREE_CODE (TREE_TYPE (value)) == UNION_TYPE)
4423 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
4428 if (TREE_CODE (endtype) == INTEGER_TYPE
4429 && TYPE_PRECISION (endtype) < POINTER_SIZE)
4432 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
4434 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
4436 /* If either term is absolute, use the other terms relocation. */
4437 if (valid0 == null_pointer_node)
4439 if (valid1 == null_pointer_node)
4445 if (TREE_CODE (endtype) == INTEGER_TYPE
4446 && TYPE_PRECISION (endtype) < POINTER_SIZE)
4449 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
4451 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
4453 /* Win if second argument is absolute. */
4454 if (valid1 == null_pointer_node)
4456 /* Win if both arguments have the same relocation.
4457 Then the value is absolute. */
4458 if (valid0 == valid1)
4459 return null_pointer_node;
4468 /* If VALUE is a compound expr all of whose expressions are constant, then
4469 return its value. Otherwise, return error_mark_node.
4471 This is for handling COMPOUND_EXPRs as initializer elements
4472 which is allowed with a warning when -pedantic is specified. */
4475 valid_compound_expr_initializer (value, endtype)
4479 if (TREE_CODE (value) == COMPOUND_EXPR)
4481 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4483 return error_mark_node;
4484 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4487 else if (! TREE_CONSTANT (value)
4488 && ! initializer_constant_valid_p (value, endtype))
4489 return error_mark_node;
4494 /* Perform appropriate conversions on the initial value of a variable,
4495 store it in the declaration DECL,
4496 and print any error messages that are appropriate.
4497 If the init is invalid, store an ERROR_MARK. */
4500 store_init_value (decl, init)
4503 register tree value, type;
4505 /* If variable's type was invalidly declared, just ignore it. */
4507 type = TREE_TYPE (decl);
4508 if (TREE_CODE (type) == ERROR_MARK)
4511 /* Digest the specified initializer into an expression. */
4513 value = digest_init (type, init, TREE_STATIC (decl),
4514 TREE_STATIC (decl) || pedantic);
4516 /* Store the expression if valid; else report error. */
4519 /* Note that this is the only place we can detect the error
4520 in a case such as struct foo bar = (struct foo) { x, y };
4521 where there is one initial value which is a constructor expression. */
4522 if (value == error_mark_node)
4524 else if (TREE_STATIC (decl) && ! TREE_CONSTANT (value))
4526 error ("initializer for static variable is not constant");
4527 value = error_mark_node;
4529 else if (TREE_STATIC (decl)
4530 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
4532 error ("initializer for static variable uses complicated arithmetic");
4533 value = error_mark_node;
4537 if (pedantic && TREE_CODE (value) == CONSTRUCTOR)
4539 if (! TREE_CONSTANT (value))
4540 pedwarn ("aggregate initializer is not constant");
4541 else if (! TREE_STATIC (value))
4542 pedwarn ("aggregate initializer uses complicated arithmetic");
4547 DECL_INITIAL (decl) = value;
4549 /* ANSI wants warnings about out-of-range constant initializers. */
4550 STRIP_TYPE_NOPS (value);
4551 constant_expression_warning (value);
4554 /* Methods for storing and printing names for error messages. */
4556 /* Implement a spelling stack that allows components of a name to be pushed
4557 and popped. Each element on the stack is this structure. */
4569 #define SPELLING_STRING 1
4570 #define SPELLING_MEMBER 2
4571 #define SPELLING_BOUNDS 3
4573 static struct spelling *spelling; /* Next stack element (unused). */
4574 static struct spelling *spelling_base; /* Spelling stack base. */
4575 static int spelling_size; /* Size of the spelling stack. */
4577 /* Macros to save and restore the spelling stack around push_... functions.
4578 Alternative to SAVE_SPELLING_STACK. */
4580 #define SPELLING_DEPTH() (spelling - spelling_base)
4581 #define RESTORE_SPELLING_DEPTH(depth) (spelling = spelling_base + depth)
4583 /* Save and restore the spelling stack around arbitrary C code. */
4585 #define SAVE_SPELLING_DEPTH(code) \
4587 int __depth = SPELLING_DEPTH (); \
4589 RESTORE_SPELLING_DEPTH (__depth); \
4592 /* Push an element on the spelling stack with type KIND and assign VALUE
4595 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4597 int depth = SPELLING_DEPTH (); \
4599 if (depth >= spelling_size) \
4601 spelling_size += 10; \
4602 if (spelling_base == 0) \
4604 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4607 = (struct spelling *) xrealloc (spelling_base, \
4608 spelling_size * sizeof (struct spelling)); \
4609 RESTORE_SPELLING_DEPTH (depth); \
4612 spelling->kind = (KIND); \
4613 spelling->MEMBER = (VALUE); \
4617 /* Push STRING on the stack. Printed literally. */
4620 push_string (string)
4623 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4626 /* Push a member name on the stack. Printed as '.' STRING. */
4629 push_member_name (decl)
4634 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4635 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4638 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4641 push_array_bounds (bounds)
4644 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4647 /* Compute the maximum size in bytes of the printed spelling. */
4652 register int size = 0;
4653 register struct spelling *p;
4655 for (p = spelling_base; p < spelling; p++)
4657 if (p->kind == SPELLING_BOUNDS)
4660 size += strlen (p->u.s) + 1;
4666 /* Print the spelling to BUFFER and return it. */
4669 print_spelling (buffer)
4670 register char *buffer;
4672 register char *d = buffer;
4674 register struct spelling *p;
4676 for (p = spelling_base; p < spelling; p++)
4677 if (p->kind == SPELLING_BOUNDS)
4679 sprintf (d, "[%d]", p->u.i);
4684 if (p->kind == SPELLING_MEMBER)
4686 for (s = p->u.s; *d = *s++; d++)
4693 /* Provide a means to pass component names derived from the spelling stack. */
4695 char initialization_message;
4697 /* Interpret the spelling of the given ERRTYPE message. */
4700 get_spelling (errtype)
4703 static char *buffer;
4704 static int size = -1;
4706 if (errtype == &initialization_message)
4708 /* Avoid counting chars */
4709 static char message[] = "initialization of `%s'";
4710 register int needed = sizeof (message) + spelling_length () + 1;
4714 buffer = (char *) xmalloc (size = needed);
4716 buffer = (char *) xrealloc (buffer, size = needed);
4718 temp = (char *) alloca (needed);
4719 sprintf (buffer, message, print_spelling (temp));
4726 /* Issue an error message for a bad initializer component.
4727 FORMAT describes the message. OFWHAT is the name for the component.
4728 LOCAL is a format string for formatting the insertion of the name
4731 If OFWHAT is null, the component name is stored on the spelling stack.
4732 If the component name is a null string, then LOCAL is omitted entirely. */
4735 error_init (format, local, ofwhat)
4736 char *format, *local, *ofwhat;
4741 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4742 buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2);
4745 sprintf (buffer, local, ofwhat);
4749 error (format, buffer);
4752 /* Issue a pedantic warning for a bad initializer component.
4753 FORMAT describes the message. OFWHAT is the name for the component.
4754 LOCAL is a format string for formatting the insertion of the name
4757 If OFWHAT is null, the component name is stored on the spelling stack.
4758 If the component name is a null string, then LOCAL is omitted entirely. */
4761 pedwarn_init (format, local, ofwhat)
4762 char *format, *local, *ofwhat;
4767 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4768 buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2);
4771 sprintf (buffer, local, ofwhat);
4775 pedwarn (format, buffer);
4778 /* Issue a warning for a bad initializer component.
4779 FORMAT describes the message. OFWHAT is the name for the component.
4780 LOCAL is a format string for formatting the insertion of the name
4783 If OFWHAT is null, the component name is stored on the spelling stack.
4784 If the component name is a null string, then LOCAL is omitted entirely. */
4787 warning_init (format, local, ofwhat)
4788 char *format, *local, *ofwhat;
4793 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4794 buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2);
4797 sprintf (buffer, local, ofwhat);
4801 warning (format, buffer);
4804 /* Digest the parser output INIT as an initializer for type TYPE.
4805 Return a C expression of type TYPE to represent the initial value.
4807 The arguments REQUIRE_CONSTANT and CONSTRUCTOR_CONSTANT request errors
4808 if non-constant initializers or elements are seen. CONSTRUCTOR_CONSTANT
4809 applies only to elements of constructors. */
4812 digest_init (type, init, require_constant, constructor_constant)
4814 int require_constant, constructor_constant;
4816 enum tree_code code = TREE_CODE (type);
4817 tree inside_init = init;
4819 if (init == error_mark_node)
4822 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4823 /* Do not use STRIP_NOPS here. We do not want an enumerator
4824 whose value is 0 to count as a null pointer constant. */
4825 if (TREE_CODE (init) == NON_LVALUE_EXPR)
4826 inside_init = TREE_OPERAND (init, 0);
4828 /* Initialization of an array of chars from a string constant
4829 optionally enclosed in braces. */
4831 if (code == ARRAY_TYPE)
4833 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4834 if ((typ1 == char_type_node
4835 || typ1 == signed_char_type_node
4836 || typ1 == unsigned_char_type_node
4837 || typ1 == unsigned_wchar_type_node
4838 || typ1 == signed_wchar_type_node)
4839 && ((inside_init && TREE_CODE (inside_init) == STRING_CST)))
4841 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4842 TYPE_MAIN_VARIANT (type)))
4845 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4847 && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node))
4849 error_init ("char-array%s initialized from wide string",
4851 return error_mark_node;
4853 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4855 && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node))
4857 error_init ("int-array%s initialized from non-wide string",
4859 return error_mark_node;
4862 TREE_TYPE (inside_init) = type;
4863 if (TYPE_DOMAIN (type) != 0
4864 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
4866 register int size = TREE_INT_CST_LOW (TYPE_SIZE (type));
4867 size = (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
4868 /* Subtract 1 (or sizeof (wchar_t))
4869 because it's ok to ignore the terminating null char
4870 that is counted in the length of the constant. */
4871 if (size < TREE_STRING_LENGTH (inside_init)
4872 - (TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node)
4873 ? TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT
4876 "initializer-string for array of chars%s is too long",
4883 /* Any type can be initialized
4884 from an expression of the same type, optionally with braces. */
4886 if (inside_init && TREE_TYPE (inside_init) != 0
4887 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4888 TYPE_MAIN_VARIANT (type))
4889 || (code == ARRAY_TYPE
4890 && comptypes (TREE_TYPE (inside_init), type))
4891 || (code == POINTER_TYPE
4892 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4893 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE)
4894 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4895 TREE_TYPE (type)))))
4897 if (code == POINTER_TYPE
4898 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4899 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE))
4900 inside_init = default_conversion (inside_init);
4901 else if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4902 && TREE_CODE (inside_init) != CONSTRUCTOR)
4904 error_init ("array%s initialized from non-constant array expression",
4906 return error_mark_node;
4909 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4910 inside_init = decl_constant_value (inside_init);
4912 /* Compound expressions can only occur here if -pedantic or
4913 -pedantic-errors is specified. In the later case, we always want
4914 an error. In the former case, we simply want a warning. */
4915 if (require_constant && pedantic
4916 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4919 = valid_compound_expr_initializer (inside_init,
4920 TREE_TYPE (inside_init));
4921 if (inside_init == error_mark_node)
4922 error_init ("initializer element%s is not constant",
4925 pedwarn_init ("initializer element%s is not constant",
4927 if (flag_pedantic_errors)
4928 inside_init = error_mark_node;
4930 else if (require_constant && ! TREE_CONSTANT (inside_init))
4932 error_init ("initializer element%s is not constant",
4934 inside_init = error_mark_node;
4936 else if (require_constant
4937 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4939 error_init ("initializer element%s is not computable at load time",
4941 inside_init = error_mark_node;
4947 /* Handle scalar types, including conversions. */
4949 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4950 || code == ENUMERAL_TYPE || code == COMPLEX_TYPE)
4952 /* Note that convert_for_assignment calls default_conversion
4953 for arrays and functions. We must not call it in the
4954 case where inside_init is a null pointer constant. */
4956 = convert_for_assignment (type, init, "initialization",
4957 NULL_TREE, NULL_TREE, 0);
4959 if (require_constant && ! TREE_CONSTANT (inside_init))
4961 error_init ("initializer element%s is not constant",
4963 inside_init = error_mark_node;
4965 else if (require_constant
4966 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4968 error_init ("initializer element%s is not computable at load time",
4970 inside_init = error_mark_node;
4976 /* Come here only for records and arrays. */
4978 if (TYPE_SIZE (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4980 error_init ("variable-sized object%s may not be initialized",
4982 return error_mark_node;
4985 /* Traditionally, you can write struct foo x = 0;
4986 and it initializes the first element of x to 0. */
4987 if (flag_traditional)
4989 tree top = 0, prev = 0, otype = type;
4990 while (TREE_CODE (type) == RECORD_TYPE
4991 || TREE_CODE (type) == ARRAY_TYPE
4992 || TREE_CODE (type) == QUAL_UNION_TYPE
4993 || TREE_CODE (type) == UNION_TYPE)
4995 tree temp = build (CONSTRUCTOR, type, NULL_TREE, NULL_TREE);
4999 TREE_OPERAND (prev, 1) = build_tree_list (NULL_TREE, temp);
5001 if (TREE_CODE (type) == ARRAY_TYPE)
5002 type = TREE_TYPE (type);
5003 else if (TYPE_FIELDS (type))
5004 type = TREE_TYPE (TYPE_FIELDS (type));
5007 error_init ("invalid initializer%s", " for `%s'", NULL);
5008 return error_mark_node;
5014 TREE_OPERAND (prev, 1)
5015 = build_tree_list (NULL_TREE,
5016 digest_init (type, init, require_constant,
5017 constructor_constant));
5021 return error_mark_node;
5023 error_init ("invalid initializer%s", " for `%s'", NULL);
5024 return error_mark_node;
5027 /* Handle initializers that use braces. */
5029 /* Type of object we are accumulating a constructor for.
5030 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
5031 static tree constructor_type;
5033 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
5035 static tree constructor_fields;
5037 /* For an ARRAY_TYPE, this is the specified index
5038 at which to store the next element we get.
5039 This is a special INTEGER_CST node that we modify in place. */
5040 static tree constructor_index;
5042 /* For an ARRAY_TYPE, this is the end index of the range
5043 to initialize with the next element, or NULL in the ordinary case
5044 where the element is used just once. */
5045 static tree constructor_range_end;
5047 /* For an ARRAY_TYPE, this is the maximum index. */
5048 static tree constructor_max_index;
5050 /* For a RECORD_TYPE, this is the first field not yet written out. */
5051 static tree constructor_unfilled_fields;
5053 /* For an ARRAY_TYPE, this is the index of the first element
5054 not yet written out.
5055 This is a special INTEGER_CST node that we modify in place. */
5056 static tree constructor_unfilled_index;
5058 /* In a RECORD_TYPE, the byte index of the next consecutive field.
5059 This is so we can generate gaps between fields, when appropriate.
5060 This is a special INTEGER_CST node that we modify in place. */
5061 static tree constructor_bit_index;
5063 /* If we are saving up the elements rather than allocating them,
5064 this is the list of elements so far (in reverse order,
5065 most recent first). */
5066 static tree constructor_elements;
5068 /* 1 if so far this constructor's elements are all compile-time constants. */
5069 static int constructor_constant;
5071 /* 1 if so far this constructor's elements are all valid address constants. */
5072 static int constructor_simple;
5074 /* 1 if this constructor is erroneous so far. */
5075 static int constructor_erroneous;
5077 /* 1 if have called defer_addressed_constants. */
5078 static int constructor_subconstants_deferred;
5080 /* List of pending elements at this constructor level.
5081 These are elements encountered out of order
5082 which belong at places we haven't reached yet in actually
5083 writing the output. */
5084 static tree constructor_pending_elts;
5086 /* The SPELLING_DEPTH of this constructor. */
5087 static int constructor_depth;
5089 /* 0 if implicitly pushing constructor levels is allowed. */
5090 int constructor_no_implicit = 0; /* 0 for C; 1 for some other languages. */
5092 /* 1 if this constructor level was entered implicitly. */
5093 static int constructor_implicit;
5095 static int require_constant_value;
5096 static int require_constant_elements;
5098 /* 1 if it is ok to output this constructor as we read it.
5099 0 means must accumulate a CONSTRUCTOR expression. */
5100 static int constructor_incremental;
5102 /* DECL node for which an initializer is being read.
5103 0 means we are reading a constructor expression
5104 such as (struct foo) {...}. */
5105 static tree constructor_decl;
5107 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
5108 static char *constructor_asmspec;
5110 /* Nonzero if this is an initializer for a top-level decl. */
5111 static int constructor_top_level;
5113 /* When we finish reading a constructor expression
5114 (constructor_decl is 0), the CONSTRUCTOR goes here. */
5115 static tree constructor_result;
5117 /* This stack has a level for each implicit or explicit level of
5118 structuring in the initializer, including the outermost one. It
5119 saves the values of most of the variables above. */
5121 struct constructor_stack
5123 struct constructor_stack *next;
5129 tree unfilled_index;
5130 tree unfilled_fields;
5136 /* If nonzero, this value should replace the entire
5137 constructor at this level. */
5138 tree replacement_value;
5147 struct constructor_stack *constructor_stack;
5149 /* This stack records separate initializers that are nested.
5150 Nested initializers can't happen in ANSI C, but GNU C allows them
5151 in cases like { ... (struct foo) { ... } ... }. */
5153 struct initializer_stack
5155 struct initializer_stack *next;
5158 struct constructor_stack *constructor_stack;
5160 struct spelling *spelling;
5161 struct spelling *spelling_base;
5165 char require_constant_value;
5166 char require_constant_elements;
5170 struct initializer_stack *initializer_stack;
5172 /* Prepare to parse and output the initializer for variable DECL. */
5175 start_init (decl, asmspec_tree, top_level)
5181 struct initializer_stack *p
5182 = (struct initializer_stack *) xmalloc (sizeof (struct initializer_stack));
5186 asmspec = TREE_STRING_POINTER (asmspec_tree);
5188 p->decl = constructor_decl;
5189 p->asmspec = constructor_asmspec;
5190 p->incremental = constructor_incremental;
5191 p->require_constant_value = require_constant_value;
5192 p->require_constant_elements = require_constant_elements;
5193 p->constructor_stack = constructor_stack;
5194 p->elements = constructor_elements;
5195 p->spelling = spelling;
5196 p->spelling_base = spelling_base;
5197 p->spelling_size = spelling_size;
5198 p->deferred = constructor_subconstants_deferred;
5199 p->top_level = constructor_top_level;
5200 p->next = initializer_stack;
5201 initializer_stack = p;
5203 constructor_decl = decl;
5204 constructor_incremental = top_level;
5205 constructor_asmspec = asmspec;
5206 constructor_subconstants_deferred = 0;
5207 constructor_top_level = top_level;
5211 require_constant_value = TREE_STATIC (decl);
5212 require_constant_elements
5213 = ((TREE_STATIC (decl) || pedantic)
5214 /* For a scalar, you can always use any value to initialize,
5215 even within braces. */
5216 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
5217 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
5218 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
5219 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
5220 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
5221 constructor_incremental |= TREE_STATIC (decl);
5225 require_constant_value = 0;
5226 require_constant_elements = 0;
5227 locus = "(anonymous)";
5230 constructor_stack = 0;
5232 missing_braces_mentioned = 0;
5236 RESTORE_SPELLING_DEPTH (0);
5239 push_string (locus);
5245 struct initializer_stack *p = initializer_stack;
5247 /* Output subconstants (string constants, usually)
5248 that were referenced within this initializer and saved up.
5249 Must do this if and only if we called defer_addressed_constants. */
5250 if (constructor_subconstants_deferred)
5251 output_deferred_addressed_constants ();
5253 /* Free the whole constructor stack of this initializer. */
5254 while (constructor_stack)
5256 struct constructor_stack *q = constructor_stack;
5257 constructor_stack = q->next;
5261 /* Pop back to the data of the outer initializer (if any). */
5262 constructor_decl = p->decl;
5263 constructor_asmspec = p->asmspec;
5264 constructor_incremental = p->incremental;
5265 require_constant_value = p->require_constant_value;
5266 require_constant_elements = p->require_constant_elements;
5267 constructor_stack = p->constructor_stack;
5268 constructor_elements = p->elements;
5269 spelling = p->spelling;
5270 spelling_base = p->spelling_base;
5271 spelling_size = p->spelling_size;
5272 constructor_subconstants_deferred = p->deferred;
5273 constructor_top_level = p->top_level;
5274 initializer_stack = p->next;
5278 /* Call here when we see the initializer is surrounded by braces.
5279 This is instead of a call to push_init_level;
5280 it is matched by a call to pop_init_level.
5282 TYPE is the type to initialize, for a constructor expression.
5283 For an initializer for a decl, TYPE is zero. */
5286 really_start_incremental_init (type)
5289 struct constructor_stack *p
5290 = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5293 type = TREE_TYPE (constructor_decl);
5295 /* Turn off constructor_incremental if type is a struct with bitfields.
5296 Do this before the first push, so that the corrected value
5297 is available in finish_init. */
5298 check_init_type_bitfields (type);
5300 p->type = constructor_type;
5301 p->fields = constructor_fields;
5302 p->index = constructor_index;
5303 p->range_end = constructor_range_end;
5304 p->max_index = constructor_max_index;
5305 p->unfilled_index = constructor_unfilled_index;
5306 p->unfilled_fields = constructor_unfilled_fields;
5307 p->bit_index = constructor_bit_index;
5308 p->elements = constructor_elements;
5309 p->constant = constructor_constant;
5310 p->simple = constructor_simple;
5311 p->erroneous = constructor_erroneous;
5312 p->pending_elts = constructor_pending_elts;
5313 p->depth = constructor_depth;
5314 p->replacement_value = 0;
5316 p->incremental = constructor_incremental;
5319 constructor_stack = p;
5321 constructor_constant = 1;
5322 constructor_simple = 1;
5323 constructor_depth = SPELLING_DEPTH ();
5324 constructor_elements = 0;
5325 constructor_pending_elts = 0;
5326 constructor_type = type;
5328 if (TREE_CODE (constructor_type) == RECORD_TYPE
5329 || TREE_CODE (constructor_type) == UNION_TYPE)
5331 constructor_fields = TYPE_FIELDS (constructor_type);
5332 /* Skip any nameless bit fields at the beginning. */
5333 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5334 && DECL_NAME (constructor_fields) == 0)
5335 constructor_fields = TREE_CHAIN (constructor_fields);
5336 constructor_unfilled_fields = constructor_fields;
5337 constructor_bit_index = copy_node (integer_zero_node);
5339 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5341 constructor_range_end = 0;
5342 if (TYPE_DOMAIN (constructor_type))
5344 constructor_max_index
5345 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5347 = copy_node (TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5350 constructor_index = copy_node (integer_zero_node);
5351 constructor_unfilled_index = copy_node (constructor_index);
5355 /* Handle the case of int x = {5}; */
5356 constructor_fields = constructor_type;
5357 constructor_unfilled_fields = constructor_type;
5360 if (constructor_incremental)
5362 int momentary = suspend_momentary ();
5363 push_obstacks_nochange ();
5364 if (TREE_PERMANENT (constructor_decl))
5365 end_temporary_allocation ();
5366 make_decl_rtl (constructor_decl, constructor_asmspec,
5367 constructor_top_level);
5368 assemble_variable (constructor_decl, constructor_top_level, 0, 1);
5370 resume_momentary (momentary);
5373 if (constructor_incremental)
5375 defer_addressed_constants ();
5376 constructor_subconstants_deferred = 1;
5380 /* Push down into a subobject, for initialization.
5381 If this is for an explicit set of braces, IMPLICIT is 0.
5382 If it is because the next element belongs at a lower level,
5386 push_init_level (implicit)
5389 struct constructor_stack *p;
5391 /* If we've exhausted any levels that didn't have braces,
5393 while (constructor_stack->implicit)
5395 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5396 || TREE_CODE (constructor_type) == UNION_TYPE)
5397 && constructor_fields == 0)
5398 process_init_element (pop_init_level (1));
5399 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5400 && tree_int_cst_lt (constructor_max_index, constructor_index))
5401 process_init_element (pop_init_level (1));
5406 /* Structure elements may require alignment. Do this now if necessary
5407 for the subaggregate, and if it comes next in sequence. Don't do
5408 this for subaggregates that will go on the pending list. */
5409 if (constructor_incremental && constructor_type != 0
5410 && TREE_CODE (constructor_type) == RECORD_TYPE && constructor_fields
5411 && constructor_fields == constructor_unfilled_fields)
5413 /* Advance to offset of this element. */
5414 if (! tree_int_cst_equal (constructor_bit_index,
5415 DECL_FIELD_BITPOS (constructor_fields)))
5417 int next = (TREE_INT_CST_LOW
5418 (DECL_FIELD_BITPOS (constructor_fields))
5420 int here = (TREE_INT_CST_LOW (constructor_bit_index)
5423 assemble_zeros (next - here);
5425 /* Indicate that we have now filled the structure up to the current
5427 constructor_unfilled_fields = constructor_fields;
5430 p = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5431 p->type = constructor_type;
5432 p->fields = constructor_fields;
5433 p->index = constructor_index;
5434 p->range_end = constructor_range_end;
5435 p->max_index = constructor_max_index;
5436 p->unfilled_index = constructor_unfilled_index;
5437 p->unfilled_fields = constructor_unfilled_fields;
5438 p->bit_index = constructor_bit_index;
5439 p->elements = constructor_elements;
5440 p->constant = constructor_constant;
5441 p->simple = constructor_simple;
5442 p->erroneous = constructor_erroneous;
5443 p->pending_elts = constructor_pending_elts;
5444 p->depth = constructor_depth;
5445 p->replacement_value = 0;
5446 p->implicit = implicit;
5447 p->incremental = constructor_incremental;
5449 p->next = constructor_stack;
5450 constructor_stack = p;
5452 constructor_constant = 1;
5453 constructor_simple = 1;
5454 constructor_depth = SPELLING_DEPTH ();
5455 constructor_elements = 0;
5456 constructor_pending_elts = 0;
5458 /* Don't die if an entire brace-pair level is superfluous
5459 in the containing level. */
5460 if (constructor_type == 0)
5462 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5463 || TREE_CODE (constructor_type) == UNION_TYPE)
5465 /* Don't die if there are extra init elts at the end. */
5466 if (constructor_fields == 0)
5467 constructor_type = 0;
5470 constructor_type = TREE_TYPE (constructor_fields);
5471 push_member_name (constructor_fields);
5472 constructor_depth++;
5473 if (constructor_fields != constructor_unfilled_fields)
5474 constructor_incremental = 0;
5477 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5479 constructor_type = TREE_TYPE (constructor_type);
5480 push_array_bounds (TREE_INT_CST_LOW (constructor_index));
5481 constructor_depth++;
5482 if (! tree_int_cst_equal (constructor_index, constructor_unfilled_index)
5483 || constructor_range_end != 0)
5484 constructor_incremental = 0;
5487 if (constructor_type == 0)
5489 error_init ("extra brace group at end of initializer%s",
5491 constructor_fields = 0;
5492 constructor_unfilled_fields = 0;
5496 /* Turn off constructor_incremental if type is a struct with bitfields. */
5497 check_init_type_bitfields (constructor_type);
5499 if (implicit && warn_missing_braces && !missing_braces_mentioned)
5501 missing_braces_mentioned = 1;
5502 warning_init ("missing braces around initializer%s", " for `%s'", NULL);
5505 if (TREE_CODE (constructor_type) == RECORD_TYPE
5506 || TREE_CODE (constructor_type) == UNION_TYPE)
5508 constructor_fields = TYPE_FIELDS (constructor_type);
5509 /* Skip any nameless bit fields at the beginning. */
5510 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5511 && DECL_NAME (constructor_fields) == 0)
5512 constructor_fields = TREE_CHAIN (constructor_fields);
5513 constructor_unfilled_fields = constructor_fields;
5514 constructor_bit_index = copy_node (integer_zero_node);
5516 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5518 constructor_range_end = 0;
5519 if (TYPE_DOMAIN (constructor_type))
5521 constructor_max_index
5522 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5524 = copy_node (TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5527 constructor_index = copy_node (integer_zero_node);
5528 constructor_unfilled_index = copy_node (constructor_index);
5532 warning_init ("braces around scalar initializer%s", " for `%s'", NULL);
5533 constructor_fields = constructor_type;
5534 constructor_unfilled_fields = constructor_type;
5538 /* Don't read a struct incrementally if it has any bitfields,
5539 because the incremental reading code doesn't know how to
5540 handle bitfields yet. */
5543 check_init_type_bitfields (type)
5546 if (TREE_CODE (type) == RECORD_TYPE)
5549 for (tail = TYPE_FIELDS (type); tail;
5550 tail = TREE_CHAIN (tail))
5552 if (DECL_C_BIT_FIELD (tail)
5553 /* This catches cases like `int foo : 8;'. */
5554 || DECL_MODE (tail) != TYPE_MODE (TREE_TYPE (tail)))
5556 constructor_incremental = 0;
5560 check_init_type_bitfields (TREE_TYPE (tail));
5564 else if (TREE_CODE (type) == ARRAY_TYPE)
5565 check_init_type_bitfields (TREE_TYPE (type));
5568 /* At the end of an implicit or explicit brace level,
5569 finish up that level of constructor.
5570 If we were outputting the elements as they are read, return 0
5571 from inner levels (process_init_element ignores that),
5572 but return error_mark_node from the outermost level
5573 (that's what we want to put in DECL_INITIAL).
5574 Otherwise, return a CONSTRUCTOR expression. */
5577 pop_init_level (implicit)
5580 struct constructor_stack *p;
5582 tree constructor = 0;
5586 /* When we come to an explicit close brace,
5587 pop any inner levels that didn't have explicit braces. */
5588 while (constructor_stack->implicit)
5589 process_init_element (pop_init_level (1));
5592 p = constructor_stack;
5594 if (constructor_type != 0)
5595 size = int_size_in_bytes (constructor_type);
5597 /* Now output all pending elements. */
5598 output_pending_init_elements (1);
5600 #if 0 /* c-parse.in warns about {}. */
5601 /* In ANSI, each brace level must have at least one element. */
5602 if (! implicit && pedantic
5603 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5604 ? integer_zerop (constructor_unfilled_index)
5605 : constructor_unfilled_fields == TYPE_FIELDS (constructor_type)))
5606 pedwarn_init ("empty braces in initializer%s", " for `%s'", NULL);
5609 /* Pad out the end of the structure. */
5611 if (p->replacement_value)
5613 /* If this closes a superfluous brace pair,
5614 just pass out the element between them. */
5615 constructor = p->replacement_value;
5616 /* If this is the top level thing within the initializer,
5617 and it's for a variable, then since we already called
5618 assemble_variable, we must output the value now. */
5619 if (p->next == 0 && constructor_decl != 0
5620 && constructor_incremental)
5622 constructor = digest_init (constructor_type, constructor,
5623 require_constant_value,
5624 require_constant_elements);
5626 /* If initializing an array of unknown size,
5627 determine the size now. */
5628 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5629 && TYPE_DOMAIN (constructor_type) == 0)
5634 push_obstacks_nochange ();
5635 if (TREE_PERMANENT (constructor_type))
5636 end_temporary_allocation ();
5638 momentary_p = suspend_momentary ();
5640 /* We shouldn't have an incomplete array type within
5642 if (constructor_stack->next)
5646 = complete_array_type (constructor_type,
5651 size = int_size_in_bytes (constructor_type);
5652 resume_momentary (momentary_p);
5656 output_constant (constructor, size);
5659 else if (constructor_type == 0)
5661 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5662 && TREE_CODE (constructor_type) != UNION_TYPE
5663 && TREE_CODE (constructor_type) != ARRAY_TYPE
5664 && ! constructor_incremental)
5666 /* A nonincremental scalar initializer--just return
5667 the element, after verifying there is just one. */
5668 if (constructor_elements == 0)
5670 error_init ("empty scalar initializer%s",
5672 constructor = error_mark_node;
5674 else if (TREE_CHAIN (constructor_elements) != 0)
5676 error_init ("extra elements in scalar initializer%s",
5678 constructor = TREE_VALUE (constructor_elements);
5681 constructor = TREE_VALUE (constructor_elements);
5683 else if (! constructor_incremental)
5685 if (constructor_erroneous)
5686 constructor = error_mark_node;
5689 int momentary = suspend_momentary ();
5691 constructor = build (CONSTRUCTOR, constructor_type, NULL_TREE,
5692 nreverse (constructor_elements));
5693 if (constructor_constant)
5694 TREE_CONSTANT (constructor) = 1;
5695 if (constructor_constant && constructor_simple)
5696 TREE_STATIC (constructor) = 1;
5698 resume_momentary (momentary);
5704 int momentary = suspend_momentary ();
5706 if (TREE_CODE (constructor_type) == RECORD_TYPE
5707 || TREE_CODE (constructor_type) == UNION_TYPE)
5709 /* Find the offset of the end of that field. */
5710 filled = size_binop (CEIL_DIV_EXPR,
5711 constructor_bit_index,
5712 size_int (BITS_PER_UNIT));
5714 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5716 /* If initializing an array of unknown size,
5717 determine the size now. */
5718 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5719 && TYPE_DOMAIN (constructor_type) == 0)
5722 = size_binop (MINUS_EXPR,
5723 constructor_unfilled_index,
5726 push_obstacks_nochange ();
5727 if (TREE_PERMANENT (constructor_type))
5728 end_temporary_allocation ();
5729 maxindex = copy_node (maxindex);
5730 TYPE_DOMAIN (constructor_type) = build_index_type (maxindex);
5731 TREE_TYPE (maxindex) = TYPE_DOMAIN (constructor_type);
5733 /* TYPE_MAX_VALUE is always one less than the number of elements
5734 in the array, because we start counting at zero. Therefore,
5735 warn only if the value is less than zero. */
5737 && (tree_int_cst_sgn (TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5739 error_with_decl (constructor_decl,
5740 "zero or negative array size `%s'");
5741 layout_type (constructor_type);
5742 size = int_size_in_bytes (constructor_type);
5746 filled = size_binop (MULT_EXPR, constructor_unfilled_index,
5747 size_in_bytes (TREE_TYPE (constructor_type)));
5753 assemble_zeros (size - TREE_INT_CST_LOW (filled));
5755 resume_momentary (momentary);
5759 constructor_type = p->type;
5760 constructor_fields = p->fields;
5761 constructor_index = p->index;
5762 constructor_range_end = p->range_end;
5763 constructor_max_index = p->max_index;
5764 constructor_unfilled_index = p->unfilled_index;
5765 constructor_unfilled_fields = p->unfilled_fields;
5766 constructor_bit_index = p->bit_index;
5767 constructor_elements = p->elements;
5768 constructor_constant = p->constant;
5769 constructor_simple = p->simple;
5770 constructor_erroneous = p->erroneous;
5771 constructor_pending_elts = p->pending_elts;
5772 constructor_depth = p->depth;
5773 constructor_incremental = p->incremental;
5774 RESTORE_SPELLING_DEPTH (constructor_depth);
5776 constructor_stack = p->next;
5779 if (constructor == 0)
5781 if (constructor_stack == 0)
5782 return error_mark_node;
5788 /* Within an array initializer, specify the next index to be initialized.
5789 FIRST is that index. If LAST is nonzero, then initialize a range
5790 of indices, running from FIRST through LAST. */
5793 set_init_index (first, last)
5796 while ((TREE_CODE (first) == NOP_EXPR
5797 || TREE_CODE (first) == CONVERT_EXPR
5798 || TREE_CODE (first) == NON_LVALUE_EXPR)
5799 && (TYPE_MODE (TREE_TYPE (first))
5800 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0)))))
5801 (first) = TREE_OPERAND (first, 0);
5803 while ((TREE_CODE (last) == NOP_EXPR
5804 || TREE_CODE (last) == CONVERT_EXPR
5805 || TREE_CODE (last) == NON_LVALUE_EXPR)
5806 && (TYPE_MODE (TREE_TYPE (last))
5807 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0)))))
5808 (last) = TREE_OPERAND (last, 0);
5810 if (TREE_CODE (first) != INTEGER_CST)
5811 error_init ("nonconstant array index in initializer%s", " for `%s'", NULL);
5812 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5813 error_init ("nonconstant array index in initializer%s", " for `%s'", NULL);
5814 else if (! constructor_unfilled_index)
5815 error_init ("array index in non-array initializer%s", " for `%s'", NULL);
5816 else if (tree_int_cst_lt (first, constructor_unfilled_index))
5817 error_init ("duplicate array index in initializer%s", " for `%s'", NULL);
5820 TREE_INT_CST_LOW (constructor_index) = TREE_INT_CST_LOW (first);
5821 TREE_INT_CST_HIGH (constructor_index) = TREE_INT_CST_HIGH (first);
5823 if (last != 0 && tree_int_cst_lt (last, first))
5824 error_init ("empty index range in initializer%s", " for `%s'", NULL);
5828 pedwarn ("ANSI C forbids specifying element to initialize");
5829 constructor_range_end = last;
5834 /* Within a struct initializer, specify the next field to be initialized. */
5837 set_init_label (fieldname)
5843 /* Don't die if an entire brace-pair level is superfluous
5844 in the containing level. */
5845 if (constructor_type == 0)
5848 for (tail = TYPE_FIELDS (constructor_type); tail;
5849 tail = TREE_CHAIN (tail))
5851 if (tail == constructor_unfilled_fields)
5853 if (DECL_NAME (tail) == fieldname)
5858 error ("unknown field `%s' specified in initializer",
5859 IDENTIFIER_POINTER (fieldname));
5861 error ("field `%s' already initialized",
5862 IDENTIFIER_POINTER (fieldname));
5865 constructor_fields = tail;
5867 pedwarn ("ANSI C forbids specifying structure member to initialize");
5871 /* "Output" the next constructor element.
5872 At top level, really output it to assembler code now.
5873 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5874 TYPE is the data type that the containing data type wants here.
5875 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5877 PENDING if non-nil means output pending elements that belong
5878 right after this element. (PENDING is normally 1;
5879 it is 0 while outputting pending elements, to avoid recursion.) */
5882 output_init_element (value, type, field, pending)
5883 tree value, type, field;
5888 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5889 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5890 && !(TREE_CODE (value) == STRING_CST
5891 && TREE_CODE (type) == ARRAY_TYPE
5892 && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE)
5893 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5894 TYPE_MAIN_VARIANT (type))))
5895 value = default_conversion (value);
5897 if (value == error_mark_node)
5898 constructor_erroneous = 1;
5899 else if (!TREE_CONSTANT (value))
5900 constructor_constant = 0;
5901 else if (initializer_constant_valid_p (value, TREE_TYPE (value)) == 0
5902 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5903 || TREE_CODE (constructor_type) == UNION_TYPE)
5904 && DECL_C_BIT_FIELD (field)
5905 && TREE_CODE (value) != INTEGER_CST))
5906 constructor_simple = 0;
5908 if (require_constant_value && ! TREE_CONSTANT (value))
5910 error_init ("initializer element%s is not constant",
5912 value = error_mark_node;
5914 else if (require_constant_elements
5915 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
5917 error_init ("initializer element%s is not computable at load time",
5919 value = error_mark_node;
5922 /* If this element duplicates one on constructor_pending_elts,
5923 print a message and ignore it. Don't do this when we're
5924 processing elements taken off constructor_pending_elts,
5925 because we'd always get spurious errors. */
5928 if (TREE_CODE (constructor_type) == RECORD_TYPE
5929 || TREE_CODE (constructor_type) == UNION_TYPE)
5931 if (purpose_member (field, constructor_pending_elts))
5933 error_init ("duplicate initializer%s", " for `%s'", NULL);
5937 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5940 for (tail = constructor_pending_elts; tail;
5941 tail = TREE_CHAIN (tail))
5942 if (TREE_PURPOSE (tail) != 0
5943 && TREE_CODE (TREE_PURPOSE (tail)) == INTEGER_CST
5944 && tree_int_cst_equal (TREE_PURPOSE (tail), constructor_index))
5949 error_init ("duplicate initializer%s", " for `%s'", NULL);
5955 /* If this element doesn't come next in sequence,
5956 put it on constructor_pending_elts. */
5957 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5958 && !tree_int_cst_equal (field, constructor_unfilled_index))
5961 /* The copy_node is needed in case field is actually
5962 constructor_index, which is modified in place. */
5963 constructor_pending_elts
5964 = tree_cons (copy_node (field),
5965 digest_init (type, value, require_constant_value,
5966 require_constant_elements),
5967 constructor_pending_elts);
5969 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5970 && field != constructor_unfilled_fields)
5972 /* We do this for records but not for unions. In a union,
5973 no matter which field is specified, it can be initialized
5974 right away since it starts at the beginning of the union. */
5976 constructor_pending_elts
5978 digest_init (type, value, require_constant_value,
5979 require_constant_elements),
5980 constructor_pending_elts);
5984 /* Otherwise, output this element either to
5985 constructor_elements or to the assembler file. */
5989 if (! constructor_incremental)
5991 if (field && TREE_CODE (field) == INTEGER_CST)
5992 field = copy_node (field);
5993 constructor_elements
5994 = tree_cons (field, digest_init (type, value,
5995 require_constant_value,
5996 require_constant_elements),
5997 constructor_elements);
6001 /* Structure elements may require alignment.
6002 Do this, if necessary. */
6003 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6005 /* Advance to offset of this element. */
6006 if (! tree_int_cst_equal (constructor_bit_index,
6007 DECL_FIELD_BITPOS (field)))
6009 int next = (TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field))
6011 int here = (TREE_INT_CST_LOW (constructor_bit_index)
6014 assemble_zeros (next - here);
6017 output_constant (digest_init (type, value,
6018 require_constant_value,
6019 require_constant_elements),
6020 int_size_in_bytes (type));
6022 /* For a record or union,
6023 keep track of end position of last field. */
6024 if (TREE_CODE (constructor_type) == RECORD_TYPE
6025 || TREE_CODE (constructor_type) == UNION_TYPE)
6027 tree temp = size_binop (PLUS_EXPR, DECL_FIELD_BITPOS (field),
6029 TREE_INT_CST_LOW (constructor_bit_index)
6030 = TREE_INT_CST_LOW (temp);
6031 TREE_INT_CST_HIGH (constructor_bit_index)
6032 = TREE_INT_CST_HIGH (temp);
6037 /* Advance the variable that indicates sequential elements output. */
6038 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6040 tree tem = size_binop (PLUS_EXPR, constructor_unfilled_index,
6042 TREE_INT_CST_LOW (constructor_unfilled_index)
6043 = TREE_INT_CST_LOW (tem);
6044 TREE_INT_CST_HIGH (constructor_unfilled_index)
6045 = TREE_INT_CST_HIGH (tem);
6047 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6048 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
6049 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6050 constructor_unfilled_fields = 0;
6052 /* Now output any pending elements which have become next. */
6054 output_pending_init_elements (0);
6058 /* Output any pending elements which have become next.
6059 As we output elements, constructor_unfilled_{fields,index}
6060 advances, which may cause other elements to become next;
6061 if so, they too are output.
6063 If ALL is 0, we return when there are
6064 no more pending elements to output now.
6066 If ALL is 1, we output space as necessary so that
6067 we can output all the pending elements. */
6070 output_pending_init_elements (all)
6078 /* Look thru the whole pending list.
6079 If we find an element that should be output now,
6080 output it. Otherwise, set NEXT to the element
6081 that comes first among those still pending. */
6084 for (tail = constructor_pending_elts; tail;
6085 tail = TREE_CHAIN (tail))
6087 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6089 if (tree_int_cst_equal (TREE_PURPOSE (tail),
6090 constructor_unfilled_index))
6092 output_init_element (TREE_VALUE (tail),
6093 TREE_TYPE (constructor_type),
6094 constructor_unfilled_index, 0);
6097 else if (tree_int_cst_lt (TREE_PURPOSE (tail),
6098 constructor_unfilled_index))
6101 || tree_int_cst_lt (TREE_PURPOSE (tail), next))
6102 next = TREE_PURPOSE (tail);
6104 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6105 || TREE_CODE (constructor_type) == UNION_TYPE)
6107 if (TREE_PURPOSE (tail) == constructor_unfilled_fields)
6109 output_init_element (TREE_VALUE (tail),
6110 TREE_TYPE (constructor_unfilled_fields),
6111 constructor_unfilled_fields,
6115 else if (constructor_unfilled_fields == 0
6116 || tree_int_cst_lt (DECL_FIELD_BITPOS (TREE_PURPOSE (tail)),
6117 DECL_FIELD_BITPOS (constructor_unfilled_fields)))
6120 || tree_int_cst_lt (DECL_FIELD_BITPOS (TREE_PURPOSE (tail)),
6121 DECL_FIELD_BITPOS (next)))
6122 next = TREE_PURPOSE (tail);
6126 /* Ordinarily return, but not if we want to output all
6127 and there are elements left. */
6128 if (! (all && next != 0))
6131 /* Generate space up to the position of NEXT. */
6132 if (constructor_incremental)
6135 tree nextpos_tree = size_int (0);
6137 if (TREE_CODE (constructor_type) == RECORD_TYPE
6138 || TREE_CODE (constructor_type) == UNION_TYPE)
6140 /* Find the last field written out, if any. */
6141 for (tail = TYPE_FIELDS (constructor_type); tail;
6142 tail = TREE_CHAIN (tail))
6143 if (TREE_CHAIN (tail) == constructor_unfilled_fields)
6147 /* Find the offset of the end of that field. */
6148 filled = size_binop (CEIL_DIV_EXPR,
6149 size_binop (PLUS_EXPR,
6150 DECL_FIELD_BITPOS (tail),
6152 size_int (BITS_PER_UNIT));
6154 filled = size_int (0);
6156 nextpos_tree = size_binop (CEIL_DIV_EXPR,
6157 DECL_FIELD_BITPOS (next),
6158 size_int (BITS_PER_UNIT));
6160 TREE_INT_CST_HIGH (constructor_bit_index)
6161 = TREE_INT_CST_HIGH (DECL_FIELD_BITPOS (next));
6162 TREE_INT_CST_LOW (constructor_bit_index)
6163 = TREE_INT_CST_LOW (DECL_FIELD_BITPOS (next));
6164 constructor_unfilled_fields = next;
6166 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6168 filled = size_binop (MULT_EXPR, constructor_unfilled_index,
6169 size_in_bytes (TREE_TYPE (constructor_type)));
6171 = size_binop (MULT_EXPR, next,
6172 size_in_bytes (TREE_TYPE (constructor_type)));
6173 TREE_INT_CST_LOW (constructor_unfilled_index)
6174 = TREE_INT_CST_LOW (next);
6175 TREE_INT_CST_HIGH (constructor_unfilled_index)
6176 = TREE_INT_CST_HIGH (next);
6183 int nextpos = TREE_INT_CST_LOW (nextpos_tree);
6185 assemble_zeros (nextpos - TREE_INT_CST_LOW (filled));
6190 /* If it's not incremental, just skip over the gap,
6191 so that after jumping to retry we will output the next
6192 successive element. */
6193 if (TREE_CODE (constructor_type) == RECORD_TYPE
6194 || TREE_CODE (constructor_type) == UNION_TYPE)
6195 constructor_unfilled_fields = next;
6196 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6198 TREE_INT_CST_LOW (constructor_unfilled_index)
6199 = TREE_INT_CST_LOW (next);
6200 TREE_INT_CST_HIGH (constructor_unfilled_index)
6201 = TREE_INT_CST_HIGH (next);
6208 /* Add one non-braced element to the current constructor level.
6209 This adjusts the current position within the constructor's type.
6210 This may also start or terminate implicit levels
6211 to handle a partly-braced initializer.
6213 Once this has found the correct level for the new element,
6214 it calls output_init_element.
6216 Note: if we are incrementally outputting this constructor,
6217 this function may be called with a null argument
6218 representing a sub-constructor that was already incrementally output.
6219 When that happens, we output nothing, but we do the bookkeeping
6220 to skip past that element of the current constructor. */
6223 process_init_element (value)
6226 tree orig_value = value;
6227 int string_flag = value != 0 && TREE_CODE (value) == STRING_CST;
6229 /* Handle superfluous braces around string cst as in
6230 char x[] = {"foo"}; */
6233 && TREE_CODE (constructor_type) == ARRAY_TYPE
6234 && TREE_CODE (TREE_TYPE (constructor_type)) == INTEGER_TYPE
6235 && integer_zerop (constructor_unfilled_index))
6237 constructor_stack->replacement_value = value;
6241 if (constructor_stack->replacement_value != 0)
6243 error_init ("excess elements in struct initializer%s",
6244 " after `%s'", NULL_PTR);
6248 /* Ignore elements of a brace group if it is entirely superfluous
6249 and has already been diagnosed. */
6250 if (constructor_type == 0)
6253 /* If we've exhausted any levels that didn't have braces,
6255 while (constructor_stack->implicit)
6257 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6258 || TREE_CODE (constructor_type) == UNION_TYPE)
6259 && constructor_fields == 0)
6260 process_init_element (pop_init_level (1));
6261 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6262 && (constructor_max_index == 0
6263 || tree_int_cst_lt (constructor_max_index,
6264 constructor_index)))
6265 process_init_element (pop_init_level (1));
6272 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6275 enum tree_code fieldcode;
6277 if (constructor_fields == 0)
6279 pedwarn_init ("excess elements in struct initializer%s",
6280 " after `%s'", NULL_PTR);
6284 fieldtype = TREE_TYPE (constructor_fields);
6285 if (fieldtype != error_mark_node)
6286 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6287 fieldcode = TREE_CODE (fieldtype);
6289 /* Accept a string constant to initialize a subarray. */
6291 && fieldcode == ARRAY_TYPE
6292 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6295 /* Otherwise, if we have come to a subaggregate,
6296 and we don't have an element of its type, push into it. */
6297 else if (value != 0 && !constructor_no_implicit
6298 && value != error_mark_node
6299 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6300 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6301 || fieldcode == UNION_TYPE))
6303 push_init_level (1);
6309 push_member_name (constructor_fields);
6310 output_init_element (value, fieldtype, constructor_fields, 1);
6311 RESTORE_SPELLING_DEPTH (constructor_depth);
6314 /* Do the bookkeeping for an element that was
6315 directly output as a constructor. */
6317 /* For a record, keep track of end position of last field. */
6318 tree temp = size_binop (PLUS_EXPR,
6319 DECL_FIELD_BITPOS (constructor_fields),
6320 DECL_SIZE (constructor_fields));
6321 TREE_INT_CST_LOW (constructor_bit_index)
6322 = TREE_INT_CST_LOW (temp);
6323 TREE_INT_CST_HIGH (constructor_bit_index)
6324 = TREE_INT_CST_HIGH (temp);
6326 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6329 constructor_fields = TREE_CHAIN (constructor_fields);
6330 /* Skip any nameless bit fields at the beginning. */
6331 while (constructor_fields != 0
6332 && DECL_C_BIT_FIELD (constructor_fields)
6333 && DECL_NAME (constructor_fields) == 0)
6334 constructor_fields = TREE_CHAIN (constructor_fields);
6337 if (TREE_CODE (constructor_type) == UNION_TYPE)
6340 enum tree_code fieldcode;
6342 if (constructor_fields == 0)
6344 pedwarn_init ("excess elements in union initializer%s",
6345 " after `%s'", NULL_PTR);
6349 fieldtype = TREE_TYPE (constructor_fields);
6350 if (fieldtype != error_mark_node)
6351 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6352 fieldcode = TREE_CODE (fieldtype);
6354 /* Accept a string constant to initialize a subarray. */
6356 && fieldcode == ARRAY_TYPE
6357 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6360 /* Otherwise, if we have come to a subaggregate,
6361 and we don't have an element of its type, push into it. */
6362 else if (value != 0 && !constructor_no_implicit
6363 && value != error_mark_node
6364 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6365 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6366 || fieldcode == UNION_TYPE))
6368 push_init_level (1);
6374 push_member_name (constructor_fields);
6375 output_init_element (value, fieldtype, constructor_fields, 1);
6376 RESTORE_SPELLING_DEPTH (constructor_depth);
6379 /* Do the bookkeeping for an element that was
6380 directly output as a constructor. */
6382 TREE_INT_CST_LOW (constructor_bit_index)
6383 = TREE_INT_CST_LOW (DECL_SIZE (constructor_fields));
6384 TREE_INT_CST_HIGH (constructor_bit_index)
6385 = TREE_INT_CST_HIGH (DECL_SIZE (constructor_fields));
6387 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6390 constructor_fields = 0;
6393 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6395 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6396 enum tree_code eltcode = TREE_CODE (elttype);
6398 /* Accept a string constant to initialize a subarray. */
6400 && eltcode == ARRAY_TYPE
6401 && TREE_CODE (TREE_TYPE (elttype)) == INTEGER_TYPE
6404 /* Otherwise, if we have come to a subaggregate,
6405 and we don't have an element of its type, push into it. */
6406 else if (value != 0 && !constructor_no_implicit
6407 && value != error_mark_node
6408 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != elttype
6409 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6410 || eltcode == UNION_TYPE))
6412 push_init_level (1);
6416 if (constructor_max_index != 0
6417 && tree_int_cst_lt (constructor_max_index, constructor_index))
6419 pedwarn_init ("excess elements in array initializer%s",
6420 " after `%s'", NULL_PTR);
6424 /* In the case of [LO .. HI] = VALUE, only evaluate VALUE once. */
6425 if (constructor_range_end)
6427 if (constructor_max_index != 0
6428 && tree_int_cst_lt (constructor_max_index,
6429 constructor_range_end))
6431 pedwarn_init ("excess elements in array initializer%s",
6432 " after `%s'", NULL_PTR);
6433 TREE_INT_CST_HIGH (constructor_range_end)
6434 = TREE_INT_CST_HIGH (constructor_max_index);
6435 TREE_INT_CST_LOW (constructor_range_end)
6436 = TREE_INT_CST_LOW (constructor_max_index);
6439 value = save_expr (value);
6442 /* Now output the actual element.
6443 Ordinarily, output once.
6444 If there is a range, repeat it till we advance past the range. */
6451 push_array_bounds (TREE_INT_CST_LOW (constructor_index));
6452 output_init_element (value, elttype, constructor_index, 1);
6453 RESTORE_SPELLING_DEPTH (constructor_depth);
6456 tem = size_binop (PLUS_EXPR, constructor_index,
6458 TREE_INT_CST_LOW (constructor_index) = TREE_INT_CST_LOW (tem);
6459 TREE_INT_CST_HIGH (constructor_index) = TREE_INT_CST_HIGH (tem);
6462 /* If we are doing the bookkeeping for an element that was
6463 directly output as a constructor,
6464 we must update constructor_unfilled_index. */
6466 TREE_INT_CST_LOW (constructor_unfilled_index)
6467 = TREE_INT_CST_LOW (constructor_index);
6468 TREE_INT_CST_HIGH (constructor_unfilled_index)
6469 = TREE_INT_CST_HIGH (constructor_index);
6472 while (! (constructor_range_end == 0
6473 || tree_int_cst_lt (constructor_range_end,
6474 constructor_index)));
6479 /* Handle the sole element allowed in a braced initializer
6480 for a scalar variable. */
6481 if (constructor_fields == 0)
6483 pedwarn_init ("excess elements in scalar initializer%s",
6484 " after `%s'", NULL_PTR);
6489 output_init_element (value, constructor_type, NULL_TREE, 1);
6490 constructor_fields = 0;
6494 /* If the (lexically) previous elments are not now saved,
6495 we can discard the storage for them. */
6496 if (constructor_incremental && constructor_pending_elts == 0 && value != 0
6497 && constructor_stack == 0)
6501 /* Expand an ASM statement with operands, handling output operands
6502 that are not variables or INDIRECT_REFS by transforming such
6503 cases into cases that expand_asm_operands can handle.
6505 Arguments are same as for expand_asm_operands. */
6508 c_expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line)
6509 tree string, outputs, inputs, clobbers;
6514 int noutputs = list_length (outputs);
6516 /* o[I] is the place that output number I should be written. */
6517 register tree *o = (tree *) alloca (noutputs * sizeof (tree));
6520 if (TREE_CODE (string) == ADDR_EXPR)
6521 string = TREE_OPERAND (string, 0);
6522 if (TREE_CODE (string) != STRING_CST)
6524 error ("asm template is not a string constant");
6528 /* Record the contents of OUTPUTS before it is modified. */
6529 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6530 o[i] = TREE_VALUE (tail);
6532 /* Perform default conversions on array and function inputs. */
6533 /* Don't do this for other types--
6534 it would screw up operands expected to be in memory. */
6535 for (i = 0, tail = inputs; tail; tail = TREE_CHAIN (tail), i++)
6536 if (TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == ARRAY_TYPE
6537 || TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == FUNCTION_TYPE)
6538 TREE_VALUE (tail) = default_conversion (TREE_VALUE (tail));
6540 /* Generate the ASM_OPERANDS insn;
6541 store into the TREE_VALUEs of OUTPUTS some trees for
6542 where the values were actually stored. */
6543 expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line);
6545 /* Copy all the intermediate outputs into the specified outputs. */
6546 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6548 if (o[i] != TREE_VALUE (tail))
6550 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
6554 /* Detect modification of read-only values.
6555 (Otherwise done by build_modify_expr.) */
6558 tree type = TREE_TYPE (o[i]);
6559 if (TREE_READONLY (o[i])
6560 || TYPE_READONLY (type)
6561 || ((TREE_CODE (type) == RECORD_TYPE
6562 || TREE_CODE (type) == UNION_TYPE)
6563 && C_TYPE_FIELDS_READONLY (type)))
6564 readonly_warning (o[i], "modification by `asm'");
6568 /* Those MODIFY_EXPRs could do autoincrements. */
6572 /* Expand a C `return' statement.
6573 RETVAL is the expression for what to return,
6574 or a null pointer for `return;' with no value. */
6577 c_expand_return (retval)
6580 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6582 if (TREE_THIS_VOLATILE (current_function_decl))
6583 warning ("function declared `noreturn' has a `return' statement");
6587 current_function_returns_null = 1;
6588 if (warn_return_type && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6589 warning ("`return' with no value, in function returning non-void");
6590 expand_null_return ();
6592 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6594 current_function_returns_null = 1;
6595 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6596 pedwarn ("`return' with a value, in function returning void");
6597 expand_return (retval);
6601 tree t = convert_for_assignment (valtype, retval, "return",
6602 NULL_TREE, NULL_TREE, 0);
6603 tree res = DECL_RESULT (current_function_decl);
6606 if (t == error_mark_node)
6609 inner = t = convert (TREE_TYPE (res), t);
6611 /* Strip any conversions, additions, and subtractions, and see if
6612 we are returning the address of a local variable. Warn if so. */
6615 switch (TREE_CODE (inner))
6617 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6619 inner = TREE_OPERAND (inner, 0);
6623 /* If the second operand of the MINUS_EXPR has a pointer
6624 type (or is converted from it), this may be valid, so
6625 don't give a warning. */
6627 tree op1 = TREE_OPERAND (inner, 1);
6629 while (! POINTER_TYPE_P (TREE_TYPE (op1))
6630 && (TREE_CODE (op1) == NOP_EXPR
6631 || TREE_CODE (op1) == NON_LVALUE_EXPR
6632 || TREE_CODE (op1) == CONVERT_EXPR))
6633 op1 = TREE_OPERAND (op1, 0);
6635 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6638 inner = TREE_OPERAND (inner, 0);
6643 inner = TREE_OPERAND (inner, 0);
6645 while (TREE_CODE_CLASS (TREE_CODE (inner)) == 'r')
6646 inner = TREE_OPERAND (inner, 0);
6648 if (TREE_CODE (inner) == VAR_DECL
6649 && ! DECL_EXTERNAL (inner)
6650 && ! TREE_STATIC (inner)
6651 && DECL_CONTEXT (inner) == current_function_decl)
6652 warning ("function returns address of local variable");
6662 t = build (MODIFY_EXPR, TREE_TYPE (res), res, t);
6663 TREE_SIDE_EFFECTS (t) = 1;
6665 current_function_returns_value = 1;
6669 /* Start a C switch statement, testing expression EXP.
6670 Return EXP if it is valid, an error node otherwise. */
6673 c_expand_start_case (exp)
6676 register enum tree_code code = TREE_CODE (TREE_TYPE (exp));
6677 tree type = TREE_TYPE (exp);
6679 if (code != INTEGER_TYPE && code != ENUMERAL_TYPE && code != ERROR_MARK)
6681 error ("switch quantity not an integer");
6682 exp = error_mark_node;
6687 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6689 if (warn_traditional
6690 && (type == long_integer_type_node
6691 || type == long_unsigned_type_node))
6692 pedwarn ("`long' switch expression not converted to `int' in ANSI C");
6694 exp = default_conversion (exp);
6695 type = TREE_TYPE (exp);
6696 index = get_unwidened (exp, NULL_TREE);
6697 /* We can't strip a conversion from a signed type to an unsigned,
6698 because if we did, int_fits_type_p would do the wrong thing
6699 when checking case values for being in range,
6700 and it's too hard to do the right thing. */
6701 if (TREE_UNSIGNED (TREE_TYPE (exp))
6702 == TREE_UNSIGNED (TREE_TYPE (index)))
6706 expand_start_case (1, exp, type, "switch statement");