1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
23 /* This file is part of the C front end.
24 It contains routines to build C expressions given their operands,
25 including computing the types of the result, C-specific error checks,
26 and some optimization.
28 There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
29 and to process initializations in declarations (since they work
30 like a strange sort of assignment). */
46 /* Nonzero if we've already printed a "missing braces around initializer"
47 message within this initializer. */
48 static int missing_braces_mentioned;
50 /* 1 if we explained undeclared var errors. */
51 static int undeclared_variable_notice;
53 static tree qualify_type PARAMS ((tree, tree));
54 static int comp_target_types PARAMS ((tree, tree));
55 static int function_types_compatible_p PARAMS ((tree, tree));
56 static int type_lists_compatible_p PARAMS ((tree, tree));
57 static tree decl_constant_value PARAMS ((tree));
58 static tree lookup_field PARAMS ((tree, tree, tree *));
59 static tree convert_arguments PARAMS ((tree, tree, tree, tree));
60 static tree pointer_int_sum PARAMS ((enum tree_code, tree, tree));
61 static tree pointer_diff PARAMS ((tree, tree));
62 static tree unary_complex_lvalue PARAMS ((enum tree_code, tree));
63 static void pedantic_lvalue_warning PARAMS ((enum tree_code));
64 static tree internal_build_compound_expr PARAMS ((tree, int));
65 static tree convert_for_assignment PARAMS ((tree, tree, const char *,
67 static void warn_for_assignment PARAMS ((const char *, const char *,
69 static tree valid_compound_expr_initializer PARAMS ((tree, tree));
70 static void push_string PARAMS ((const char *));
71 static void push_member_name PARAMS ((tree));
72 static void push_array_bounds PARAMS ((int));
73 static int spelling_length PARAMS ((void));
74 static char *print_spelling PARAMS ((char *));
75 static void warning_init PARAMS ((const char *));
76 static tree digest_init PARAMS ((tree, tree, int, int));
77 static void check_init_type_bitfields PARAMS ((tree));
78 static void output_init_element PARAMS ((tree, tree, tree, int));
79 static void output_pending_init_elements PARAMS ((int));
80 static void add_pending_init PARAMS ((tree, tree));
81 static int pending_init_member PARAMS ((tree));
83 /* Do `exp = require_complete_type (exp);' to make sure exp
84 does not have an incomplete type. (That includes void types.) */
87 require_complete_type (value)
90 tree type = TREE_TYPE (value);
92 if (TREE_CODE (value) == ERROR_MARK)
93 return error_mark_node;
95 /* First, detect a valid value with a complete type. */
96 if (COMPLETE_TYPE_P (type))
99 incomplete_type_error (value, type);
100 return error_mark_node;
103 /* Print an error message for invalid use of an incomplete type.
104 VALUE is the expression that was used (or 0 if that isn't known)
105 and TYPE is the type that was invalid. */
108 incomplete_type_error (value, type)
112 const char *type_code_string;
114 /* Avoid duplicate error message. */
115 if (TREE_CODE (type) == ERROR_MARK)
118 if (value != 0 && (TREE_CODE (value) == VAR_DECL
119 || TREE_CODE (value) == PARM_DECL))
120 error ("`%s' has an incomplete type",
121 IDENTIFIER_POINTER (DECL_NAME (value)));
125 /* We must print an error message. Be clever about what it says. */
127 switch (TREE_CODE (type))
130 type_code_string = "struct";
134 type_code_string = "union";
138 type_code_string = "enum";
142 error ("invalid use of void expression");
146 if (TYPE_DOMAIN (type))
148 type = TREE_TYPE (type);
151 error ("invalid use of array with unspecified bounds");
158 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
159 error ("invalid use of undefined type `%s %s'",
160 type_code_string, IDENTIFIER_POINTER (TYPE_NAME (type)));
162 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
163 error ("invalid use of incomplete typedef `%s'",
164 IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
168 /* Return a variant of TYPE which has all the type qualifiers of LIKE
169 as well as those of TYPE. */
172 qualify_type (type, like)
175 return c_build_qualified_type (type,
176 TYPE_QUALS (type) | TYPE_QUALS (like));
179 /* Return the common type of two types.
180 We assume that comptypes has already been done and returned 1;
181 if that isn't so, this may crash. In particular, we assume that qualifiers
184 This is the type for the result of most arithmetic operations
185 if the operands have the given two types. */
191 register enum tree_code code1;
192 register enum tree_code code2;
195 /* Save time if the two types are the same. */
197 if (t1 == t2) return t1;
199 /* If one type is nonsense, use the other. */
200 if (t1 == error_mark_node)
202 if (t2 == error_mark_node)
205 /* Merge the attributes. */
206 attributes = merge_machine_type_attributes (t1, t2);
208 /* Treat an enum type as the unsigned integer type of the same width. */
210 if (TREE_CODE (t1) == ENUMERAL_TYPE)
211 t1 = type_for_size (TYPE_PRECISION (t1), 1);
212 if (TREE_CODE (t2) == ENUMERAL_TYPE)
213 t2 = type_for_size (TYPE_PRECISION (t2), 1);
215 code1 = TREE_CODE (t1);
216 code2 = TREE_CODE (t2);
218 /* If one type is complex, form the common type of the non-complex
219 components, then make that complex. Use T1 or T2 if it is the
221 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
223 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
224 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
225 tree subtype = common_type (subtype1, subtype2);
227 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
228 return build_type_attribute_variant (t1, attributes);
229 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
230 return build_type_attribute_variant (t2, attributes);
232 return build_type_attribute_variant (build_complex_type (subtype),
240 /* If only one is real, use it as the result. */
242 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
243 return build_type_attribute_variant (t1, attributes);
245 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
246 return build_type_attribute_variant (t2, attributes);
248 /* Both real or both integers; use the one with greater precision. */
250 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
251 return build_type_attribute_variant (t1, attributes);
252 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
253 return build_type_attribute_variant (t2, attributes);
255 /* Same precision. Prefer longs to ints even when same size. */
257 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
258 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
259 return build_type_attribute_variant (long_unsigned_type_node,
262 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
263 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
265 /* But preserve unsignedness from the other type,
266 since long cannot hold all the values of an unsigned int. */
267 if (TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
268 t1 = long_unsigned_type_node;
270 t1 = long_integer_type_node;
271 return build_type_attribute_variant (t1, attributes);
274 /* Likewise, prefer long double to double even if same size. */
275 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
276 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
277 return build_type_attribute_variant (long_double_type_node,
280 /* Otherwise prefer the unsigned one. */
282 if (TREE_UNSIGNED (t1))
283 return build_type_attribute_variant (t1, attributes);
285 return build_type_attribute_variant (t2, attributes);
288 /* For two pointers, do this recursively on the target type,
289 and combine the qualifiers of the two types' targets. */
290 /* This code was turned off; I don't know why.
291 But ANSI C specifies doing this with the qualifiers.
292 So I turned it on again. */
294 tree pointed_to_1 = TREE_TYPE (t1);
295 tree pointed_to_2 = TREE_TYPE (t2);
296 tree target = common_type (TYPE_MAIN_VARIANT (pointed_to_1),
297 TYPE_MAIN_VARIANT (pointed_to_2));
298 t1 = build_pointer_type (c_build_qualified_type
300 TYPE_QUALS (pointed_to_1) |
301 TYPE_QUALS (pointed_to_2)));
302 return build_type_attribute_variant (t1, attributes);
305 t1 = build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2)));
306 return build_type_attribute_variant (t1, attributes);
311 tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
312 /* Save space: see if the result is identical to one of the args. */
313 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
314 return build_type_attribute_variant (t1, attributes);
315 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
316 return build_type_attribute_variant (t2, attributes);
317 /* Merge the element types, and have a size if either arg has one. */
318 t1 = build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
319 return build_type_attribute_variant (t1, attributes);
323 /* Function types: prefer the one that specified arg types.
324 If both do, merge the arg types. Also merge the return types. */
326 tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
327 tree p1 = TYPE_ARG_TYPES (t1);
328 tree p2 = TYPE_ARG_TYPES (t2);
333 /* Save space: see if the result is identical to one of the args. */
334 if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2))
335 return build_type_attribute_variant (t1, attributes);
336 if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1))
337 return build_type_attribute_variant (t2, attributes);
339 /* Simple way if one arg fails to specify argument types. */
340 if (TYPE_ARG_TYPES (t1) == 0)
342 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
343 return build_type_attribute_variant (t1, attributes);
345 if (TYPE_ARG_TYPES (t2) == 0)
347 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
348 return build_type_attribute_variant (t1, attributes);
351 /* If both args specify argument types, we must merge the two
352 lists, argument by argument. */
354 len = list_length (p1);
357 for (i = 0; i < len; i++)
358 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
363 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
365 /* A null type means arg type is not specified.
366 Take whatever the other function type has. */
367 if (TREE_VALUE (p1) == 0)
369 TREE_VALUE (n) = TREE_VALUE (p2);
372 if (TREE_VALUE (p2) == 0)
374 TREE_VALUE (n) = TREE_VALUE (p1);
378 /* Given wait (union {union wait *u; int *i} *)
379 and wait (union wait *),
380 prefer union wait * as type of parm. */
381 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
382 && TREE_VALUE (p1) != TREE_VALUE (p2))
385 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
386 memb; memb = TREE_CHAIN (memb))
387 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2)))
389 TREE_VALUE (n) = TREE_VALUE (p2);
391 pedwarn ("function types not truly compatible in ISO C");
395 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
396 && TREE_VALUE (p2) != TREE_VALUE (p1))
399 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
400 memb; memb = TREE_CHAIN (memb))
401 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1)))
403 TREE_VALUE (n) = TREE_VALUE (p1);
405 pedwarn ("function types not truly compatible in ISO C");
409 TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2));
413 t1 = build_function_type (valtype, newargs);
414 /* ... falls through ... */
418 return build_type_attribute_variant (t1, attributes);
423 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
424 or various other operations. Return 2 if they are compatible
425 but a warning may be needed if you use them together. */
428 comptypes (type1, type2)
431 register tree t1 = type1;
432 register tree t2 = type2;
435 /* Suppress errors caused by previously reported errors. */
437 if (t1 == t2 || !t1 || !t2
438 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
441 /* If either type is the internal version of sizetype, return the
443 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
444 && TYPE_DOMAIN (t1) != 0)
445 t1 = TYPE_DOMAIN (t1);
447 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
448 && TYPE_DOMAIN (t2) != 0)
449 t2 = TYPE_DOMAIN (t2);
451 /* Treat an enum type as the integer type of the same width and
454 if (TREE_CODE (t1) == ENUMERAL_TYPE)
455 t1 = type_for_size (TYPE_PRECISION (t1), TREE_UNSIGNED (t1));
456 if (TREE_CODE (t2) == ENUMERAL_TYPE)
457 t2 = type_for_size (TYPE_PRECISION (t2), TREE_UNSIGNED (t2));
462 /* Different classes of types can't be compatible. */
464 if (TREE_CODE (t1) != TREE_CODE (t2)) return 0;
466 /* Qualifiers must match. */
468 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
471 /* Allow for two different type nodes which have essentially the same
472 definition. Note that we already checked for equality of the type
473 qualifiers (just above). */
475 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
478 #ifndef COMP_TYPE_ATTRIBUTES
479 #define COMP_TYPE_ATTRIBUTES(t1,t2) 1
482 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
483 if (! (attrval = COMP_TYPE_ATTRIBUTES (t1, t2)))
486 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
489 switch (TREE_CODE (t1))
492 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
493 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
497 val = function_types_compatible_p (t1, t2);
502 tree d1 = TYPE_DOMAIN (t1);
503 tree d2 = TYPE_DOMAIN (t2);
506 /* Target types must match incl. qualifiers. */
507 if (TREE_TYPE (t1) != TREE_TYPE (t2)
508 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
511 /* Sizes must match unless one is missing or variable. */
512 if (d1 == 0 || d2 == 0 || d1 == d2
513 || TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
514 || TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
515 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST
516 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)
519 if (! tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
520 || ! tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
527 if (maybe_objc_comptypes (t1, t2, 0) == 1)
534 return attrval == 2 && val == 1 ? 2 : val;
537 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
538 ignoring their qualifiers. */
541 comp_target_types (ttl, ttr)
546 /* Give maybe_objc_comptypes a crack at letting these types through. */
547 if ((val = maybe_objc_comptypes (ttl, ttr, 1)) >= 0)
550 val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)),
551 TYPE_MAIN_VARIANT (TREE_TYPE (ttr)));
553 if (val == 2 && pedantic)
554 pedwarn ("types are not quite compatible");
558 /* Subroutines of `comptypes'. */
560 /* Return 1 if two function types F1 and F2 are compatible.
561 If either type specifies no argument types,
562 the other must specify a fixed number of self-promoting arg types.
563 Otherwise, if one type specifies only the number of arguments,
564 the other must specify that number of self-promoting arg types.
565 Otherwise, the argument types must match. */
568 function_types_compatible_p (f1, f2)
572 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
576 if (!(TREE_TYPE (f1) == TREE_TYPE (f2)
577 || (val = comptypes (TREE_TYPE (f1), TREE_TYPE (f2)))))
580 args1 = TYPE_ARG_TYPES (f1);
581 args2 = TYPE_ARG_TYPES (f2);
583 /* An unspecified parmlist matches any specified parmlist
584 whose argument types don't need default promotions. */
588 if (!self_promoting_args_p (args2))
590 /* If one of these types comes from a non-prototype fn definition,
591 compare that with the other type's arglist.
592 If they don't match, ask for a warning (but no error). */
593 if (TYPE_ACTUAL_ARG_TYPES (f1)
594 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
600 if (!self_promoting_args_p (args1))
602 if (TYPE_ACTUAL_ARG_TYPES (f2)
603 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
608 /* Both types have argument lists: compare them and propagate results. */
609 val1 = type_lists_compatible_p (args1, args2);
610 return val1 != 1 ? val1 : val;
613 /* Check two lists of types for compatibility,
614 returning 0 for incompatible, 1 for compatible,
615 or 2 for compatible with warning. */
618 type_lists_compatible_p (args1, args2)
621 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
627 if (args1 == 0 && args2 == 0)
629 /* If one list is shorter than the other,
630 they fail to match. */
631 if (args1 == 0 || args2 == 0)
633 /* A null pointer instead of a type
634 means there is supposed to be an argument
635 but nothing is specified about what type it has.
636 So match anything that self-promotes. */
637 if (TREE_VALUE (args1) == 0)
639 if (simple_type_promotes_to (TREE_VALUE (args2)) != NULL_TREE)
642 else if (TREE_VALUE (args2) == 0)
644 if (simple_type_promotes_to (TREE_VALUE (args1)) != NULL_TREE)
647 else if (! (newval = comptypes (TREE_VALUE (args1), TREE_VALUE (args2))))
649 /* Allow wait (union {union wait *u; int *i} *)
650 and wait (union wait *) to be compatible. */
651 if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE
652 && (TYPE_NAME (TREE_VALUE (args1)) == 0
653 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args1)))
654 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST
655 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)),
656 TYPE_SIZE (TREE_VALUE (args2))))
659 for (memb = TYPE_FIELDS (TREE_VALUE (args1));
660 memb; memb = TREE_CHAIN (memb))
661 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2)))
666 else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE
667 && (TYPE_NAME (TREE_VALUE (args2)) == 0
668 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args2)))
669 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST
670 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)),
671 TYPE_SIZE (TREE_VALUE (args1))))
674 for (memb = TYPE_FIELDS (TREE_VALUE (args2));
675 memb; memb = TREE_CHAIN (memb))
676 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1)))
685 /* comptypes said ok, but record if it said to warn. */
689 args1 = TREE_CHAIN (args1);
690 args2 = TREE_CHAIN (args2);
694 /* Compute the value of the `sizeof' operator. */
700 enum tree_code code = TREE_CODE (type);
702 if (code == FUNCTION_TYPE)
704 if (pedantic || warn_pointer_arith)
705 pedwarn ("sizeof applied to a function type");
706 return size_one_node;
708 if (code == VOID_TYPE)
710 if (pedantic || warn_pointer_arith)
711 pedwarn ("sizeof applied to a void type");
712 return size_one_node;
715 if (code == ERROR_MARK)
716 return size_one_node;
718 if (!COMPLETE_TYPE_P (type))
720 error ("sizeof applied to an incomplete type");
721 return size_zero_node;
724 /* Convert in case a char is more than one unit. */
725 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
726 size_int (TYPE_PRECISION (char_type_node)
731 c_sizeof_nowarn (type)
734 enum tree_code code = TREE_CODE (type);
736 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
737 return size_one_node;
739 if (!COMPLETE_TYPE_P (type))
740 return size_zero_node;
742 /* Convert in case a char is more than one unit. */
743 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
744 size_int (TYPE_PRECISION (char_type_node)
748 /* Compute the size to increment a pointer by. */
751 c_size_in_bytes (type)
754 enum tree_code code = TREE_CODE (type);
756 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
757 return size_one_node;
759 if (!COMPLETE_OR_VOID_TYPE_P (type))
761 error ("arithmetic on pointer to an incomplete type");
762 return size_one_node;
765 /* Convert in case a char is more than one unit. */
766 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
767 size_int (TYPE_PRECISION (char_type_node)
771 /* Implement the __alignof keyword: Return the minimum required
772 alignment of TYPE, measured in bytes. */
778 enum tree_code code = TREE_CODE (type);
780 if (code == FUNCTION_TYPE)
781 return size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
783 if (code == VOID_TYPE || code == ERROR_MARK)
784 return size_one_node;
786 if (!COMPLETE_TYPE_P (type))
788 error ("__alignof__ applied to an incomplete type");
789 return size_zero_node;
792 return size_int (TYPE_ALIGN (type) / BITS_PER_UNIT);
795 /* Implement the __alignof keyword: Return the minimum required
796 alignment of EXPR, measured in bytes. For VAR_DECL's and
797 FIELD_DECL's return DECL_ALIGN (which can be set from an
798 "aligned" __attribute__ specification). */
801 c_alignof_expr (expr)
804 if (TREE_CODE (expr) == VAR_DECL)
805 return size_int (DECL_ALIGN (expr) / BITS_PER_UNIT);
807 if (TREE_CODE (expr) == COMPONENT_REF
808 && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1)))
810 error ("`__alignof' applied to a bit-field");
811 return size_one_node;
813 else if (TREE_CODE (expr) == COMPONENT_REF
814 && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
815 return size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT);
817 if (TREE_CODE (expr) == INDIRECT_REF)
819 tree t = TREE_OPERAND (expr, 0);
821 int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
823 while (TREE_CODE (t) == NOP_EXPR
824 && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
828 t = TREE_OPERAND (t, 0);
829 thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
830 if (thisalign > bestalign)
831 best = t, bestalign = thisalign;
833 return c_alignof (TREE_TYPE (TREE_TYPE (best)));
836 return c_alignof (TREE_TYPE (expr));
839 /* Return either DECL or its known constant value (if it has one). */
842 decl_constant_value (decl)
845 if (/* Don't change a variable array bound or initial value to a constant
846 in a place where a variable is invalid. */
847 current_function_decl != 0
849 && ! TREE_THIS_VOLATILE (decl)
850 && TREE_READONLY (decl) && ! ITERATOR_P (decl)
851 && DECL_INITIAL (decl) != 0
852 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
853 /* This is invalid if initial value is not constant.
854 If it has either a function call, a memory reference,
855 or a variable, then re-evaluating it could give different results. */
856 && TREE_CONSTANT (DECL_INITIAL (decl))
857 /* Check for cases where this is sub-optimal, even though valid. */
858 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR
859 && DECL_MODE (decl) != BLKmode)
860 return DECL_INITIAL (decl);
864 /* Perform default promotions for C data used in expressions.
865 Arrays and functions are converted to pointers;
866 enumeral types or short or char, to int.
867 In addition, manifest constants symbols are replaced by their values. */
870 default_conversion (exp)
873 register tree type = TREE_TYPE (exp);
874 register enum tree_code code = TREE_CODE (type);
876 /* Constants can be used directly unless they're not loadable. */
877 if (TREE_CODE (exp) == CONST_DECL)
878 exp = DECL_INITIAL (exp);
880 /* Replace a nonvolatile const static variable with its value unless
881 it is an array, in which case we must be sure that taking the
882 address of the array produces consistent results. */
883 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
885 exp = decl_constant_value (exp);
886 type = TREE_TYPE (exp);
889 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
892 Do not use STRIP_NOPS here! It will remove conversions from pointer
893 to integer and cause infinite recursion. */
894 while (TREE_CODE (exp) == NON_LVALUE_EXPR
895 || (TREE_CODE (exp) == NOP_EXPR
896 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
897 exp = TREE_OPERAND (exp, 0);
899 /* Normally convert enums to int,
900 but convert wide enums to something wider. */
901 if (code == ENUMERAL_TYPE)
903 type = type_for_size (MAX (TYPE_PRECISION (type),
904 TYPE_PRECISION (integer_type_node)),
906 || (TYPE_PRECISION (type)
907 >= TYPE_PRECISION (integer_type_node)))
908 && TREE_UNSIGNED (type)));
910 return convert (type, exp);
913 if (TREE_CODE (exp) == COMPONENT_REF
914 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
915 /* If it's thinner than an int, promote it like a
916 C_PROMOTING_INTEGER_TYPE_P, otherwise leave it alone. */
917 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
918 TYPE_PRECISION (integer_type_node)))
919 return convert (flag_traditional && TREE_UNSIGNED (type)
920 ? unsigned_type_node : integer_type_node,
923 if (C_PROMOTING_INTEGER_TYPE_P (type))
925 /* Traditionally, unsignedness is preserved in default promotions.
926 Also preserve unsignedness if not really getting any wider. */
927 if (TREE_UNSIGNED (type)
929 || TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
930 return convert (unsigned_type_node, exp);
932 return convert (integer_type_node, exp);
935 if (flag_traditional && !flag_allow_single_precision
936 && TYPE_MAIN_VARIANT (type) == float_type_node)
937 return convert (double_type_node, exp);
939 if (code == VOID_TYPE)
941 error ("void value not ignored as it ought to be");
942 return error_mark_node;
944 if (code == FUNCTION_TYPE)
946 return build_unary_op (ADDR_EXPR, exp, 0);
948 if (code == ARRAY_TYPE)
951 tree restype = TREE_TYPE (type);
956 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r' || DECL_P (exp))
958 constp = TREE_READONLY (exp);
959 volatilep = TREE_THIS_VOLATILE (exp);
962 if (TYPE_QUALS (type) || constp || volatilep)
964 = c_build_qualified_type (restype,
966 | (constp * TYPE_QUAL_CONST)
967 | (volatilep * TYPE_QUAL_VOLATILE));
969 if (TREE_CODE (exp) == INDIRECT_REF)
970 return convert (TYPE_POINTER_TO (restype),
971 TREE_OPERAND (exp, 0));
973 if (TREE_CODE (exp) == COMPOUND_EXPR)
975 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
976 return build (COMPOUND_EXPR, TREE_TYPE (op1),
977 TREE_OPERAND (exp, 0), op1);
981 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
983 error ("invalid use of non-lvalue array");
984 return error_mark_node;
987 ptrtype = build_pointer_type (restype);
989 if (TREE_CODE (exp) == VAR_DECL)
991 /* ??? This is not really quite correct
992 in that the type of the operand of ADDR_EXPR
993 is not the target type of the type of the ADDR_EXPR itself.
994 Question is, can this lossage be avoided? */
995 adr = build1 (ADDR_EXPR, ptrtype, exp);
996 if (mark_addressable (exp) == 0)
997 return error_mark_node;
998 TREE_CONSTANT (adr) = staticp (exp);
999 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1002 /* This way is better for a COMPONENT_REF since it can
1003 simplify the offset for a component. */
1004 adr = build_unary_op (ADDR_EXPR, exp, 1);
1005 return convert (ptrtype, adr);
1010 /* Look up component name in the structure type definition.
1012 If this component name is found indirectly within an anonymous union,
1013 store in *INDIRECT the component which directly contains
1014 that anonymous union. Otherwise, set *INDIRECT to 0. */
1017 lookup_field (type, component, indirect)
1018 tree type, component;
1023 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1024 to the field elements. Use a binary search on this array to quickly
1025 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1026 will always be set for structures which have many elements. */
1028 if (TYPE_LANG_SPECIFIC (type))
1031 tree *field_array = &TYPE_LANG_SPECIFIC (type)->elts[0];
1033 field = TYPE_FIELDS (type);
1035 top = TYPE_LANG_SPECIFIC (type)->len;
1036 while (top - bot > 1)
1038 half = (top - bot + 1) >> 1;
1039 field = field_array[bot+half];
1041 if (DECL_NAME (field) == NULL_TREE)
1043 /* Step through all anon unions in linear fashion. */
1044 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1046 tree anon = 0, junk;
1048 field = field_array[bot++];
1049 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1050 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1051 anon = lookup_field (TREE_TYPE (field), component, &junk);
1053 if (anon != NULL_TREE)
1060 /* Entire record is only anon unions. */
1064 /* Restart the binary search, with new lower bound. */
1068 if (DECL_NAME (field) == component)
1070 if (DECL_NAME (field) < component)
1076 if (DECL_NAME (field_array[bot]) == component)
1077 field = field_array[bot];
1078 else if (DECL_NAME (field) != component)
1083 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1085 if (DECL_NAME (field) == NULL_TREE)
1090 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1091 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1092 anon = lookup_field (TREE_TYPE (field), component, &junk);
1094 if (anon != NULL_TREE)
1101 if (DECL_NAME (field) == component)
1106 *indirect = NULL_TREE;
1110 /* Make an expression to refer to the COMPONENT field of
1111 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1114 build_component_ref (datum, component)
1115 tree datum, component;
1117 register tree type = TREE_TYPE (datum);
1118 register enum tree_code code = TREE_CODE (type);
1119 register tree field = NULL;
1122 /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it
1123 unless we are not to support things not strictly ANSI. */
1124 switch (TREE_CODE (datum))
1128 tree value = build_component_ref (TREE_OPERAND (datum, 1), component);
1129 return build (COMPOUND_EXPR, TREE_TYPE (value),
1130 TREE_OPERAND (datum, 0), value);
1133 return build_conditional_expr
1134 (TREE_OPERAND (datum, 0),
1135 build_component_ref (TREE_OPERAND (datum, 1), component),
1136 build_component_ref (TREE_OPERAND (datum, 2), component));
1142 /* See if there is a field or component with name COMPONENT. */
1144 if (code == RECORD_TYPE || code == UNION_TYPE)
1148 if (!COMPLETE_TYPE_P (type))
1150 incomplete_type_error (NULL_TREE, type);
1151 return error_mark_node;
1154 field = lookup_field (type, component, &indirect);
1158 error ("%s has no member named `%s'",
1159 code == RECORD_TYPE ? "structure" : "union",
1160 IDENTIFIER_POINTER (component));
1161 return error_mark_node;
1163 if (TREE_TYPE (field) == error_mark_node)
1164 return error_mark_node;
1166 /* If FIELD was found buried within an anonymous union,
1167 make one COMPONENT_REF to get that anonymous union,
1168 then fall thru to make a second COMPONENT_REF to get FIELD. */
1171 ref = build (COMPONENT_REF, TREE_TYPE (indirect), datum, indirect);
1172 if (TREE_READONLY (datum) || TREE_READONLY (indirect))
1173 TREE_READONLY (ref) = 1;
1174 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (indirect))
1175 TREE_THIS_VOLATILE (ref) = 1;
1179 ref = build (COMPONENT_REF, TREE_TYPE (field), datum, field);
1181 if (TREE_READONLY (datum) || TREE_READONLY (field))
1182 TREE_READONLY (ref) = 1;
1183 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (field))
1184 TREE_THIS_VOLATILE (ref) = 1;
1188 else if (code != ERROR_MARK)
1189 error ("request for member `%s' in something not a structure or union",
1190 IDENTIFIER_POINTER (component));
1192 return error_mark_node;
1195 /* Given an expression PTR for a pointer, return an expression
1196 for the value pointed to.
1197 ERRORSTRING is the name of the operator to appear in error messages. */
1200 build_indirect_ref (ptr, errorstring)
1202 const char *errorstring;
1204 register tree pointer = default_conversion (ptr);
1205 register tree type = TREE_TYPE (pointer);
1207 if (TREE_CODE (type) == POINTER_TYPE)
1209 if (TREE_CODE (pointer) == ADDR_EXPR
1211 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1212 == TREE_TYPE (type)))
1213 return TREE_OPERAND (pointer, 0);
1216 tree t = TREE_TYPE (type);
1217 register tree ref = build1 (INDIRECT_REF,
1218 TYPE_MAIN_VARIANT (t), pointer);
1220 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1222 error ("dereferencing pointer to incomplete type");
1223 return error_mark_node;
1225 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1226 warning ("dereferencing `void *' pointer");
1228 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1229 so that we get the proper error message if the result is used
1230 to assign to. Also, &* is supposed to be a no-op.
1231 And ANSI C seems to specify that the type of the result
1232 should be the const type. */
1233 /* A de-reference of a pointer to const is not a const. It is valid
1234 to change it via some other pointer. */
1235 TREE_READONLY (ref) = TYPE_READONLY (t);
1236 TREE_SIDE_EFFECTS (ref)
1237 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer) || flag_volatile;
1238 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1242 else if (TREE_CODE (pointer) != ERROR_MARK)
1243 error ("invalid type argument of `%s'", errorstring);
1244 return error_mark_node;
1247 /* This handles expressions of the form "a[i]", which denotes
1250 This is logically equivalent in C to *(a+i), but we may do it differently.
1251 If A is a variable or a member, we generate a primitive ARRAY_REF.
1252 This avoids forcing the array out of registers, and can work on
1253 arrays that are not lvalues (for example, members of structures returned
1257 build_array_ref (array, index)
1262 error ("subscript missing in array reference");
1263 return error_mark_node;
1266 if (TREE_TYPE (array) == error_mark_node
1267 || TREE_TYPE (index) == error_mark_node)
1268 return error_mark_node;
1270 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
1271 && TREE_CODE (array) != INDIRECT_REF)
1275 /* Subscripting with type char is likely to lose
1276 on a machine where chars are signed.
1277 So warn on any machine, but optionally.
1278 Don't warn for unsigned char since that type is safe.
1279 Don't warn for signed char because anyone who uses that
1280 must have done so deliberately. */
1281 if (warn_char_subscripts
1282 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1283 warning ("array subscript has type `char'");
1285 /* Apply default promotions *after* noticing character types. */
1286 index = default_conversion (index);
1288 /* Require integer *after* promotion, for sake of enums. */
1289 if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE)
1291 error ("array subscript is not an integer");
1292 return error_mark_node;
1295 /* An array that is indexed by a non-constant
1296 cannot be stored in a register; we must be able to do
1297 address arithmetic on its address.
1298 Likewise an array of elements of variable size. */
1299 if (TREE_CODE (index) != INTEGER_CST
1300 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1301 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1303 if (mark_addressable (array) == 0)
1304 return error_mark_node;
1306 /* An array that is indexed by a constant value which is not within
1307 the array bounds cannot be stored in a register either; because we
1308 would get a crash in store_bit_field/extract_bit_field when trying
1309 to access a non-existent part of the register. */
1310 if (TREE_CODE (index) == INTEGER_CST
1311 && TYPE_VALUES (TREE_TYPE (array))
1312 && ! int_fits_type_p (index, TYPE_VALUES (TREE_TYPE (array))))
1314 if (mark_addressable (array) == 0)
1315 return error_mark_node;
1321 while (TREE_CODE (foo) == COMPONENT_REF)
1322 foo = TREE_OPERAND (foo, 0);
1323 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
1324 pedwarn ("ISO C forbids subscripting `register' array");
1325 else if (! flag_isoc99 && ! lvalue_p (foo))
1326 pedwarn ("ISO C89 forbids subscripting non-lvalue array");
1329 type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array)));
1330 rval = build (ARRAY_REF, type, array, index);
1331 /* Array ref is const/volatile if the array elements are
1332 or if the array is. */
1333 TREE_READONLY (rval)
1334 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1335 | TREE_READONLY (array));
1336 TREE_SIDE_EFFECTS (rval)
1337 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1338 | TREE_SIDE_EFFECTS (array));
1339 TREE_THIS_VOLATILE (rval)
1340 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1341 /* This was added by rms on 16 Nov 91.
1342 It fixes vol struct foo *a; a->elts[1]
1343 in an inline function.
1344 Hope it doesn't break something else. */
1345 | TREE_THIS_VOLATILE (array));
1346 return require_complete_type (fold (rval));
1350 tree ar = default_conversion (array);
1351 tree ind = default_conversion (index);
1353 /* Do the same warning check as above, but only on the part that's
1354 syntactically the index and only if it is also semantically
1356 if (warn_char_subscripts
1357 && TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE
1358 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1359 warning ("subscript has type `char'");
1361 /* Put the integer in IND to simplify error checking. */
1362 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
1369 if (ar == error_mark_node)
1372 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE
1373 || TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) == FUNCTION_TYPE)
1375 error ("subscripted value is neither array nor pointer");
1376 return error_mark_node;
1378 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
1380 error ("array subscript is not an integer");
1381 return error_mark_node;
1384 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0),
1389 /* Build an external reference to identifier ID. FUN indicates
1390 whether this will be used for a function call. */
1392 build_external_ref (id, fun)
1397 tree decl = lookup_name (id);
1398 tree objc_ivar = lookup_objc_ivar (id);
1400 if (!decl || decl == error_mark_node || C_DECL_ANTICIPATED (decl))
1406 if (!decl || decl == error_mark_node)
1407 /* Ordinary implicit function declaration. */
1408 ref = implicitly_declare (id);
1411 /* Implicit declaration of built-in function. Don't
1412 change the built-in declaration, but don't let this
1413 go by silently, either. */
1414 implicit_decl_warning (id);
1416 /* only issue this warning once */
1417 C_DECL_ANTICIPATED (decl) = 0;
1423 /* Reference to undeclared variable, including reference to
1424 builtin outside of function-call context. */
1425 if (current_function_decl == 0)
1426 error ("`%s' undeclared here (not in a function)",
1427 IDENTIFIER_POINTER (id));
1430 if (IDENTIFIER_GLOBAL_VALUE (id) != error_mark_node
1431 || IDENTIFIER_ERROR_LOCUS (id) != current_function_decl)
1433 error ("`%s' undeclared (first use in this function)",
1434 IDENTIFIER_POINTER (id));
1436 if (! undeclared_variable_notice)
1438 error ("(Each undeclared identifier is reported only once");
1439 error ("for each function it appears in.)");
1440 undeclared_variable_notice = 1;
1443 IDENTIFIER_GLOBAL_VALUE (id) = error_mark_node;
1444 IDENTIFIER_ERROR_LOCUS (id) = current_function_decl;
1446 return error_mark_node;
1451 /* Properly declared variable or function reference. */
1454 else if (decl != objc_ivar && IDENTIFIER_LOCAL_VALUE (id))
1456 warning ("local declaration of `%s' hides instance variable",
1457 IDENTIFIER_POINTER (id));
1464 if (TREE_TYPE (ref) == error_mark_node)
1465 return error_mark_node;
1467 assemble_external (ref);
1468 TREE_USED (ref) = 1;
1470 if (TREE_CODE (ref) == CONST_DECL)
1472 ref = DECL_INITIAL (ref);
1473 TREE_CONSTANT (ref) = 1;
1479 /* Build a function call to function FUNCTION with parameters PARAMS.
1480 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1481 TREE_VALUE of each node is a parameter-expression.
1482 FUNCTION's data type may be a function type or a pointer-to-function. */
1485 build_function_call (function, params)
1486 tree function, params;
1488 register tree fntype, fundecl = 0;
1489 register tree coerced_params;
1490 tree name = NULL_TREE, assembler_name = NULL_TREE, result;
1492 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1493 STRIP_TYPE_NOPS (function);
1495 /* Convert anything with function type to a pointer-to-function. */
1496 if (TREE_CODE (function) == FUNCTION_DECL)
1498 name = DECL_NAME (function);
1499 assembler_name = DECL_ASSEMBLER_NAME (function);
1501 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1502 (because calling an inline function does not mean the function
1503 needs to be separately compiled). */
1504 fntype = build_type_variant (TREE_TYPE (function),
1505 TREE_READONLY (function),
1506 TREE_THIS_VOLATILE (function));
1508 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
1511 function = default_conversion (function);
1513 fntype = TREE_TYPE (function);
1515 if (TREE_CODE (fntype) == ERROR_MARK)
1516 return error_mark_node;
1518 if (!(TREE_CODE (fntype) == POINTER_TYPE
1519 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
1521 error ("called object is not a function");
1522 return error_mark_node;
1525 /* fntype now gets the type of function pointed to. */
1526 fntype = TREE_TYPE (fntype);
1528 /* Convert the parameters to the types declared in the
1529 function prototype, or apply default promotions. */
1532 = convert_arguments (TYPE_ARG_TYPES (fntype), params, name, fundecl);
1534 /* Check for errors in format strings. */
1536 if (warn_format && (name || assembler_name))
1537 check_function_format (name, assembler_name, coerced_params);
1539 /* Recognize certain built-in functions so we can make tree-codes
1540 other than CALL_EXPR. We do this when it enables fold-const.c
1541 to do something useful. */
1543 if (TREE_CODE (function) == ADDR_EXPR
1544 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
1545 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
1547 result = expand_tree_builtin (TREE_OPERAND (function, 0),
1548 params, coerced_params);
1553 result = build (CALL_EXPR, TREE_TYPE (fntype),
1554 function, coerced_params, NULL_TREE);
1556 TREE_SIDE_EFFECTS (result) = 1;
1557 if (VOID_TYPE_P (TREE_TYPE (result)))
1559 return require_complete_type (result);
1562 /* Convert the argument expressions in the list VALUES
1563 to the types in the list TYPELIST. The result is a list of converted
1564 argument expressions.
1566 If TYPELIST is exhausted, or when an element has NULL as its type,
1567 perform the default conversions.
1569 PARMLIST is the chain of parm decls for the function being called.
1570 It may be 0, if that info is not available.
1571 It is used only for generating error messages.
1573 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1575 This is also where warnings about wrong number of args are generated.
1577 Both VALUES and the returned value are chains of TREE_LIST nodes
1578 with the elements of the list in the TREE_VALUE slots of those nodes. */
1581 convert_arguments (typelist, values, name, fundecl)
1582 tree typelist, values, name, fundecl;
1584 register tree typetail, valtail;
1585 register tree result = NULL;
1588 /* Scan the given expressions and types, producing individual
1589 converted arguments and pushing them on RESULT in reverse order. */
1591 for (valtail = values, typetail = typelist, parmnum = 0;
1593 valtail = TREE_CHAIN (valtail), parmnum++)
1595 register tree type = typetail ? TREE_VALUE (typetail) : 0;
1596 register tree val = TREE_VALUE (valtail);
1598 if (type == void_type_node)
1601 error ("too many arguments to function `%s'",
1602 IDENTIFIER_POINTER (name));
1604 error ("too many arguments to function");
1608 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1609 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1610 to convert automatically to a pointer. */
1611 if (TREE_CODE (val) == NON_LVALUE_EXPR)
1612 val = TREE_OPERAND (val, 0);
1614 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
1615 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE)
1616 val = default_conversion (val);
1618 val = require_complete_type (val);
1622 /* Formal parm type is specified by a function prototype. */
1625 if (!COMPLETE_TYPE_P (type))
1627 error ("type of formal parameter %d is incomplete", parmnum + 1);
1632 /* Optionally warn about conversions that
1633 differ from the default conversions. */
1634 if (warn_conversion)
1636 int formal_prec = TYPE_PRECISION (type);
1638 if (INTEGRAL_TYPE_P (type)
1639 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1640 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1641 else if (TREE_CODE (type) == COMPLEX_TYPE
1642 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1643 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1644 else if (TREE_CODE (type) == REAL_TYPE
1645 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1646 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1647 else if (TREE_CODE (type) == REAL_TYPE
1648 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
1649 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1650 /* ??? At some point, messages should be written about
1651 conversions between complex types, but that's too messy
1653 else if (TREE_CODE (type) == REAL_TYPE
1654 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1656 /* Warn if any argument is passed as `float',
1657 since without a prototype it would be `double'. */
1658 if (formal_prec == TYPE_PRECISION (float_type_node))
1659 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1661 /* Detect integer changing in width or signedness. */
1662 else if (INTEGRAL_TYPE_P (type)
1663 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1665 tree would_have_been = default_conversion (val);
1666 tree type1 = TREE_TYPE (would_have_been);
1668 if (TREE_CODE (type) == ENUMERAL_TYPE
1669 && type == TREE_TYPE (val))
1670 /* No warning if function asks for enum
1671 and the actual arg is that enum type. */
1673 else if (formal_prec != TYPE_PRECISION (type1))
1674 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1675 else if (TREE_UNSIGNED (type) == TREE_UNSIGNED (type1))
1677 /* Don't complain if the formal parameter type
1678 is an enum, because we can't tell now whether
1679 the value was an enum--even the same enum. */
1680 else if (TREE_CODE (type) == ENUMERAL_TYPE)
1682 else if (TREE_CODE (val) == INTEGER_CST
1683 && int_fits_type_p (val, type))
1684 /* Change in signedness doesn't matter
1685 if a constant value is unaffected. */
1687 /* Likewise for a constant in a NOP_EXPR. */
1688 else if (TREE_CODE (val) == NOP_EXPR
1689 && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST
1690 && int_fits_type_p (TREE_OPERAND (val, 0), type))
1692 #if 0 /* We never get such tree structure here. */
1693 else if (TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE
1694 && int_fits_type_p (TYPE_MIN_VALUE (TREE_TYPE (val)), type)
1695 && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE (val)), type))
1696 /* Change in signedness doesn't matter
1697 if an enum value is unaffected. */
1700 /* If the value is extended from a narrower
1701 unsigned type, it doesn't matter whether we
1702 pass it as signed or unsigned; the value
1703 certainly is the same either way. */
1704 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
1705 && TREE_UNSIGNED (TREE_TYPE (val)))
1707 else if (TREE_UNSIGNED (type))
1708 warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1);
1710 warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1);
1714 parmval = convert_for_assignment (type, val,
1715 (char *) 0, /* arg passing */
1716 fundecl, name, parmnum + 1);
1718 if (PROMOTE_PROTOTYPES
1719 && (TREE_CODE (type) == INTEGER_TYPE
1720 || TREE_CODE (type) == ENUMERAL_TYPE)
1721 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
1722 parmval = default_conversion (parmval);
1724 result = tree_cons (NULL_TREE, parmval, result);
1726 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
1727 && (TYPE_PRECISION (TREE_TYPE (val))
1728 < TYPE_PRECISION (double_type_node)))
1729 /* Convert `float' to `double'. */
1730 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
1732 /* Convert `short' and `char' to full-size `int'. */
1733 result = tree_cons (NULL_TREE, default_conversion (val), result);
1736 typetail = TREE_CHAIN (typetail);
1739 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
1742 error ("too few arguments to function `%s'",
1743 IDENTIFIER_POINTER (name));
1745 error ("too few arguments to function");
1748 return nreverse (result);
1751 /* This is the entry point used by the parser
1752 for binary operators in the input.
1753 In addition to constructing the expression,
1754 we check for operands that were written with other binary operators
1755 in a way that is likely to confuse the user. */
1758 parser_build_binary_op (code, arg1, arg2)
1759 enum tree_code code;
1762 tree result = build_binary_op (code, arg1, arg2, 1);
1765 char class1 = TREE_CODE_CLASS (TREE_CODE (arg1));
1766 char class2 = TREE_CODE_CLASS (TREE_CODE (arg2));
1767 enum tree_code code1 = ERROR_MARK;
1768 enum tree_code code2 = ERROR_MARK;
1770 if (class1 == 'e' || class1 == '1'
1771 || class1 == '2' || class1 == '<')
1772 code1 = C_EXP_ORIGINAL_CODE (arg1);
1773 if (class2 == 'e' || class2 == '1'
1774 || class2 == '2' || class2 == '<')
1775 code2 = C_EXP_ORIGINAL_CODE (arg2);
1777 /* Check for cases such as x+y<<z which users are likely
1778 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1779 is cleared to prevent these warnings. */
1780 if (warn_parentheses)
1782 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
1784 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1785 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1786 warning ("suggest parentheses around + or - inside shift");
1789 if (code == TRUTH_ORIF_EXPR)
1791 if (code1 == TRUTH_ANDIF_EXPR
1792 || code2 == TRUTH_ANDIF_EXPR)
1793 warning ("suggest parentheses around && within ||");
1796 if (code == BIT_IOR_EXPR)
1798 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
1799 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1800 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
1801 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1802 warning ("suggest parentheses around arithmetic in operand of |");
1803 /* Check cases like x|y==z */
1804 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1805 warning ("suggest parentheses around comparison in operand of |");
1808 if (code == BIT_XOR_EXPR)
1810 if (code1 == BIT_AND_EXPR
1811 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1812 || code2 == BIT_AND_EXPR
1813 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1814 warning ("suggest parentheses around arithmetic in operand of ^");
1815 /* Check cases like x^y==z */
1816 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1817 warning ("suggest parentheses around comparison in operand of ^");
1820 if (code == BIT_AND_EXPR)
1822 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1823 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1824 warning ("suggest parentheses around + or - in operand of &");
1825 /* Check cases like x&y==z */
1826 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1827 warning ("suggest parentheses around comparison in operand of &");
1831 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1832 if (TREE_CODE_CLASS (code) == '<' && extra_warnings
1833 && (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<'))
1834 warning ("comparisons like X<=Y<=Z do not have their mathematical meaning");
1836 unsigned_conversion_warning (result, arg1);
1837 unsigned_conversion_warning (result, arg2);
1838 overflow_warning (result);
1840 class = TREE_CODE_CLASS (TREE_CODE (result));
1842 /* Record the code that was specified in the source,
1843 for the sake of warnings about confusing nesting. */
1844 if (class == 'e' || class == '1'
1845 || class == '2' || class == '<')
1846 C_SET_EXP_ORIGINAL_CODE (result, code);
1849 int flag = TREE_CONSTANT (result);
1850 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1851 so that convert_for_assignment wouldn't strip it.
1852 That way, we got warnings for things like p = (1 - 1).
1853 But it turns out we should not get those warnings. */
1854 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
1855 C_SET_EXP_ORIGINAL_CODE (result, code);
1856 TREE_CONSTANT (result) = flag;
1862 /* Build a binary-operation expression without default conversions.
1863 CODE is the kind of expression to build.
1864 This function differs from `build' in several ways:
1865 the data type of the result is computed and recorded in it,
1866 warnings are generated if arg data types are invalid,
1867 special handling for addition and subtraction of pointers is known,
1868 and some optimization is done (operations on narrow ints
1869 are done in the narrower type when that gives the same result).
1870 Constant folding is also done before the result is returned.
1872 Note that the operands will never have enumeral types, or function
1873 or array types, because either they will have the default conversions
1874 performed or they have both just been converted to some other type in which
1875 the arithmetic is to be done. */
1878 build_binary_op (code, orig_op0, orig_op1, convert_p)
1879 enum tree_code code;
1880 tree orig_op0, orig_op1;
1884 register enum tree_code code0, code1;
1887 /* Expression code to give to the expression when it is built.
1888 Normally this is CODE, which is what the caller asked for,
1889 but in some special cases we change it. */
1890 register enum tree_code resultcode = code;
1892 /* Data type in which the computation is to be performed.
1893 In the simplest cases this is the common type of the arguments. */
1894 register tree result_type = NULL;
1896 /* Nonzero means operands have already been type-converted
1897 in whatever way is necessary.
1898 Zero means they need to be converted to RESULT_TYPE. */
1901 /* Nonzero means create the expression with this type, rather than
1903 tree build_type = 0;
1905 /* Nonzero means after finally constructing the expression
1906 convert it to this type. */
1907 tree final_type = 0;
1909 /* Nonzero if this is an operation like MIN or MAX which can
1910 safely be computed in short if both args are promoted shorts.
1911 Also implies COMMON.
1912 -1 indicates a bitwise operation; this makes a difference
1913 in the exact conditions for when it is safe to do the operation
1914 in a narrower mode. */
1917 /* Nonzero if this is a comparison operation;
1918 if both args are promoted shorts, compare the original shorts.
1919 Also implies COMMON. */
1920 int short_compare = 0;
1922 /* Nonzero if this is a right-shift operation, which can be computed on the
1923 original short and then promoted if the operand is a promoted short. */
1924 int short_shift = 0;
1926 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1931 op0 = default_conversion (orig_op0);
1932 op1 = default_conversion (orig_op1);
1940 type0 = TREE_TYPE (op0);
1941 type1 = TREE_TYPE (op1);
1943 /* The expression codes of the data types of the arguments tell us
1944 whether the arguments are integers, floating, pointers, etc. */
1945 code0 = TREE_CODE (type0);
1946 code1 = TREE_CODE (type1);
1948 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1949 STRIP_TYPE_NOPS (op0);
1950 STRIP_TYPE_NOPS (op1);
1952 /* If an error was already reported for one of the arguments,
1953 avoid reporting another error. */
1955 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
1956 return error_mark_node;
1961 /* Handle the pointer + int case. */
1962 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
1963 return pointer_int_sum (PLUS_EXPR, op0, op1);
1964 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
1965 return pointer_int_sum (PLUS_EXPR, op1, op0);
1971 /* Subtraction of two similar pointers.
1972 We must subtract them as integers, then divide by object size. */
1973 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
1974 && comp_target_types (type0, type1))
1975 return pointer_diff (op0, op1);
1976 /* Handle pointer minus int. Just like pointer plus int. */
1977 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
1978 return pointer_int_sum (MINUS_EXPR, op0, op1);
1987 case TRUNC_DIV_EXPR:
1989 case FLOOR_DIV_EXPR:
1990 case ROUND_DIV_EXPR:
1991 case EXACT_DIV_EXPR:
1992 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
1993 || code0 == COMPLEX_TYPE)
1994 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
1995 || code1 == COMPLEX_TYPE))
1997 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
1998 resultcode = RDIV_EXPR;
2000 /* Although it would be tempting to shorten always here, that
2001 loses on some targets, since the modulo instruction is
2002 undefined if the quotient can't be represented in the
2003 computation mode. We shorten only if unsigned or if
2004 dividing by something we know != -1. */
2005 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
2006 || (TREE_CODE (op1) == INTEGER_CST
2007 && ! integer_all_onesp (op1)));
2013 case BIT_ANDTC_EXPR:
2016 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2018 /* If one operand is a constant, and the other is a short type
2019 that has been converted to an int,
2020 really do the work in the short type and then convert the
2021 result to int. If we are lucky, the constant will be 0 or 1
2022 in the short type, making the entire operation go away. */
2023 if (TREE_CODE (op0) == INTEGER_CST
2024 && TREE_CODE (op1) == NOP_EXPR
2025 && TYPE_PRECISION (type1) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))
2026 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0))))
2028 final_type = result_type;
2029 op1 = TREE_OPERAND (op1, 0);
2030 result_type = TREE_TYPE (op1);
2032 if (TREE_CODE (op1) == INTEGER_CST
2033 && TREE_CODE (op0) == NOP_EXPR
2034 && TYPE_PRECISION (type0) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))
2035 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2037 final_type = result_type;
2038 op0 = TREE_OPERAND (op0, 0);
2039 result_type = TREE_TYPE (op0);
2043 case TRUNC_MOD_EXPR:
2044 case FLOOR_MOD_EXPR:
2045 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2047 /* Although it would be tempting to shorten always here, that loses
2048 on some targets, since the modulo instruction is undefined if the
2049 quotient can't be represented in the computation mode. We shorten
2050 only if unsigned or if dividing by something we know != -1. */
2051 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
2052 || (TREE_CODE (op1) == INTEGER_CST
2053 && ! integer_all_onesp (op1)));
2058 case TRUTH_ANDIF_EXPR:
2059 case TRUTH_ORIF_EXPR:
2060 case TRUTH_AND_EXPR:
2062 case TRUTH_XOR_EXPR:
2063 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
2064 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2065 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
2066 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2068 /* Result of these operations is always an int,
2069 but that does not mean the operands should be
2070 converted to ints! */
2071 result_type = integer_type_node;
2072 op0 = truthvalue_conversion (op0);
2073 op1 = truthvalue_conversion (op1);
2078 /* Shift operations: result has same type as first operand;
2079 always convert second operand to int.
2080 Also set SHORT_SHIFT if shifting rightward. */
2083 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2085 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2087 if (tree_int_cst_sgn (op1) < 0)
2088 warning ("right shift count is negative");
2091 if (! integer_zerop (op1))
2094 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2095 warning ("right shift count >= width of type");
2099 /* Use the type of the value to be shifted.
2100 This is what most traditional C compilers do. */
2101 result_type = type0;
2102 /* Unless traditional, convert the shift-count to an integer,
2103 regardless of size of value being shifted. */
2104 if (! flag_traditional)
2106 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2107 op1 = convert (integer_type_node, op1);
2108 /* Avoid converting op1 to result_type later. */
2115 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2117 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2119 if (tree_int_cst_sgn (op1) < 0)
2120 warning ("left shift count is negative");
2122 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2123 warning ("left shift count >= width of type");
2126 /* Use the type of the value to be shifted.
2127 This is what most traditional C compilers do. */
2128 result_type = type0;
2129 /* Unless traditional, convert the shift-count to an integer,
2130 regardless of size of value being shifted. */
2131 if (! flag_traditional)
2133 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2134 op1 = convert (integer_type_node, op1);
2135 /* Avoid converting op1 to result_type later. */
2143 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2145 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2147 if (tree_int_cst_sgn (op1) < 0)
2148 warning ("shift count is negative");
2149 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2150 warning ("shift count >= width of type");
2153 /* Use the type of the value to be shifted.
2154 This is what most traditional C compilers do. */
2155 result_type = type0;
2156 /* Unless traditional, convert the shift-count to an integer,
2157 regardless of size of value being shifted. */
2158 if (! flag_traditional)
2160 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2161 op1 = convert (integer_type_node, op1);
2162 /* Avoid converting op1 to result_type later. */
2170 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
2171 warning ("comparing floating point with == or != is unsafe");
2172 /* Result of comparison is always int,
2173 but don't convert the args to int! */
2174 build_type = integer_type_node;
2175 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2176 || code0 == COMPLEX_TYPE)
2177 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2178 || code1 == COMPLEX_TYPE))
2180 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2182 register tree tt0 = TREE_TYPE (type0);
2183 register tree tt1 = TREE_TYPE (type1);
2184 /* Anything compares with void *. void * compares with anything.
2185 Otherwise, the targets must be compatible
2186 and both must be object or both incomplete. */
2187 if (comp_target_types (type0, type1))
2188 result_type = common_type (type0, type1);
2189 else if (VOID_TYPE_P (tt0))
2191 /* op0 != orig_op0 detects the case of something
2192 whose value is 0 but which isn't a valid null ptr const. */
2193 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
2194 && TREE_CODE (tt1) == FUNCTION_TYPE)
2195 pedwarn ("ISO C forbids comparison of `void *' with function pointer");
2197 else if (VOID_TYPE_P (tt1))
2199 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
2200 && TREE_CODE (tt0) == FUNCTION_TYPE)
2201 pedwarn ("ISO C forbids comparison of `void *' with function pointer");
2204 pedwarn ("comparison of distinct pointer types lacks a cast");
2206 if (result_type == NULL_TREE)
2207 result_type = ptr_type_node;
2209 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2210 && integer_zerop (op1))
2211 result_type = type0;
2212 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2213 && integer_zerop (op0))
2214 result_type = type1;
2215 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2217 result_type = type0;
2218 if (! flag_traditional)
2219 pedwarn ("comparison between pointer and integer");
2221 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2223 result_type = type1;
2224 if (! flag_traditional)
2225 pedwarn ("comparison between pointer and integer");
2231 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2232 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2234 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2236 if (comp_target_types (type0, type1))
2238 result_type = common_type (type0, type1);
2240 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2241 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
2245 result_type = ptr_type_node;
2246 pedwarn ("comparison of distinct pointer types lacks a cast");
2255 build_type = integer_type_node;
2256 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2257 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2259 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2261 if (comp_target_types (type0, type1))
2263 result_type = common_type (type0, type1);
2264 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
2265 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
2266 pedwarn ("comparison of complete and incomplete pointers");
2268 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2269 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
2273 result_type = ptr_type_node;
2274 pedwarn ("comparison of distinct pointer types lacks a cast");
2277 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2278 && integer_zerop (op1))
2280 result_type = type0;
2281 if (pedantic || extra_warnings)
2282 pedwarn ("ordered comparison of pointer with integer zero");
2284 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2285 && integer_zerop (op0))
2287 result_type = type1;
2289 pedwarn ("ordered comparison of pointer with integer zero");
2291 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2293 result_type = type0;
2294 if (! flag_traditional)
2295 pedwarn ("comparison between pointer and integer");
2297 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2299 result_type = type1;
2300 if (! flag_traditional)
2301 pedwarn ("comparison between pointer and integer");
2305 case UNORDERED_EXPR:
2312 build_type = integer_type_node;
2313 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
2315 error ("unordered comparison on non-floating point argument");
2316 return error_mark_node;
2325 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2327 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2329 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
2331 if (shorten || common || short_compare)
2332 result_type = common_type (type0, type1);
2334 /* For certain operations (which identify themselves by shorten != 0)
2335 if both args were extended from the same smaller type,
2336 do the arithmetic in that type and then extend.
2338 shorten !=0 and !=1 indicates a bitwise operation.
2339 For them, this optimization is safe only if
2340 both args are zero-extended or both are sign-extended.
2341 Otherwise, we might change the result.
2342 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2343 but calculated in (unsigned short) it would be (unsigned short)-1. */
2345 if (shorten && none_complex)
2347 int unsigned0, unsigned1;
2348 tree arg0 = get_narrower (op0, &unsigned0);
2349 tree arg1 = get_narrower (op1, &unsigned1);
2350 /* UNS is 1 if the operation to be done is an unsigned one. */
2351 int uns = TREE_UNSIGNED (result_type);
2354 final_type = result_type;
2356 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2357 but it *requires* conversion to FINAL_TYPE. */
2359 if ((TYPE_PRECISION (TREE_TYPE (op0))
2360 == TYPE_PRECISION (TREE_TYPE (arg0)))
2361 && TREE_TYPE (op0) != final_type)
2362 unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
2363 if ((TYPE_PRECISION (TREE_TYPE (op1))
2364 == TYPE_PRECISION (TREE_TYPE (arg1)))
2365 && TREE_TYPE (op1) != final_type)
2366 unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
2368 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2370 /* For bitwise operations, signedness of nominal type
2371 does not matter. Consider only how operands were extended. */
2375 /* Note that in all three cases below we refrain from optimizing
2376 an unsigned operation on sign-extended args.
2377 That would not be valid. */
2379 /* Both args variable: if both extended in same way
2380 from same width, do it in that width.
2381 Do it unsigned if args were zero-extended. */
2382 if ((TYPE_PRECISION (TREE_TYPE (arg0))
2383 < TYPE_PRECISION (result_type))
2384 && (TYPE_PRECISION (TREE_TYPE (arg1))
2385 == TYPE_PRECISION (TREE_TYPE (arg0)))
2386 && unsigned0 == unsigned1
2387 && (unsigned0 || !uns))
2389 = signed_or_unsigned_type (unsigned0,
2390 common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
2391 else if (TREE_CODE (arg0) == INTEGER_CST
2392 && (unsigned1 || !uns)
2393 && (TYPE_PRECISION (TREE_TYPE (arg1))
2394 < TYPE_PRECISION (result_type))
2395 && (type = signed_or_unsigned_type (unsigned1,
2397 int_fits_type_p (arg0, type)))
2399 else if (TREE_CODE (arg1) == INTEGER_CST
2400 && (unsigned0 || !uns)
2401 && (TYPE_PRECISION (TREE_TYPE (arg0))
2402 < TYPE_PRECISION (result_type))
2403 && (type = signed_or_unsigned_type (unsigned0,
2405 int_fits_type_p (arg1, type)))
2409 /* Shifts can be shortened if shifting right. */
2414 tree arg0 = get_narrower (op0, &unsigned_arg);
2416 final_type = result_type;
2418 if (arg0 == op0 && final_type == TREE_TYPE (op0))
2419 unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
2421 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
2422 /* We can shorten only if the shift count is less than the
2423 number of bits in the smaller type size. */
2424 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
2425 /* If arg is sign-extended and then unsigned-shifted,
2426 we can simulate this with a signed shift in arg's type
2427 only if the extended result is at least twice as wide
2428 as the arg. Otherwise, the shift could use up all the
2429 ones made by sign-extension and bring in zeros.
2430 We can't optimize that case at all, but in most machines
2431 it never happens because available widths are 2**N. */
2432 && (!TREE_UNSIGNED (final_type)
2434 || (2 * TYPE_PRECISION (TREE_TYPE (arg0))
2435 <= TYPE_PRECISION (result_type))))
2437 /* Do an unsigned shift if the operand was zero-extended. */
2439 = signed_or_unsigned_type (unsigned_arg,
2441 /* Convert value-to-be-shifted to that type. */
2442 if (TREE_TYPE (op0) != result_type)
2443 op0 = convert (result_type, op0);
2448 /* Comparison operations are shortened too but differently.
2449 They identify themselves by setting short_compare = 1. */
2453 /* Don't write &op0, etc., because that would prevent op0
2454 from being kept in a register.
2455 Instead, make copies of the our local variables and
2456 pass the copies by reference, then copy them back afterward. */
2457 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
2458 enum tree_code xresultcode = resultcode;
2460 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
2465 op0 = xop0, op1 = xop1;
2467 resultcode = xresultcode;
2469 if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare != 0)
2470 && skip_evaluation == 0)
2472 int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0));
2473 int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1));
2474 int unsignedp0, unsignedp1;
2475 tree primop0 = get_narrower (op0, &unsignedp0);
2476 tree primop1 = get_narrower (op1, &unsignedp1);
2480 STRIP_TYPE_NOPS (xop0);
2481 STRIP_TYPE_NOPS (xop1);
2483 /* Give warnings for comparisons between signed and unsigned
2484 quantities that may fail.
2486 Do the checking based on the original operand trees, so that
2487 casts will be considered, but default promotions won't be.
2489 Do not warn if the comparison is being done in a signed type,
2490 since the signed type will only be chosen if it can represent
2491 all the values of the unsigned type. */
2492 if (! TREE_UNSIGNED (result_type))
2494 /* Do not warn if both operands are the same signedness. */
2495 else if (op0_signed == op1_signed)
2502 sop = xop0, uop = xop1;
2504 sop = xop1, uop = xop0;
2506 /* Do not warn if the signed quantity is an
2507 unsuffixed integer literal (or some static
2508 constant expression involving such literals or a
2509 conditional expression involving such literals)
2510 and it is non-negative. */
2511 if (tree_expr_nonnegative_p (sop))
2513 /* Do not warn if the comparison is an equality operation,
2514 the unsigned quantity is an integral constant, and it
2515 would fit in the result if the result were signed. */
2516 else if (TREE_CODE (uop) == INTEGER_CST
2517 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
2518 && int_fits_type_p (uop, signed_type (result_type)))
2520 /* Do not warn if the unsigned quantity is an enumeration
2521 constant and its maximum value would fit in the result
2522 if the result were signed. */
2523 else if (TREE_CODE (uop) == INTEGER_CST
2524 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
2525 && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE(uop)),
2526 signed_type (result_type)))
2529 warning ("comparison between signed and unsigned");
2532 /* Warn if two unsigned values are being compared in a size
2533 larger than their original size, and one (and only one) is the
2534 result of a `~' operator. This comparison will always fail.
2536 Also warn if one operand is a constant, and the constant
2537 does not have all bits set that are set in the ~ operand
2538 when it is extended. */
2540 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
2541 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
2543 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
2544 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
2547 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
2550 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
2553 HOST_WIDE_INT constant, mask;
2554 int unsignedp, bits;
2556 if (host_integerp (primop0, 0))
2559 unsignedp = unsignedp1;
2560 constant = tree_low_cst (primop0, 0);
2565 unsignedp = unsignedp0;
2566 constant = tree_low_cst (primop1, 0);
2569 bits = TYPE_PRECISION (TREE_TYPE (primop));
2570 if (bits < TYPE_PRECISION (result_type)
2571 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
2573 mask = (~ (HOST_WIDE_INT) 0) << bits;
2574 if ((mask & constant) != mask)
2575 warning ("comparison of promoted ~unsigned with constant");
2578 else if (unsignedp0 && unsignedp1
2579 && (TYPE_PRECISION (TREE_TYPE (primop0))
2580 < TYPE_PRECISION (result_type))
2581 && (TYPE_PRECISION (TREE_TYPE (primop1))
2582 < TYPE_PRECISION (result_type)))
2583 warning ("comparison of promoted ~unsigned with unsigned");
2589 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2590 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2591 Then the expression will be built.
2592 It will be given type FINAL_TYPE if that is nonzero;
2593 otherwise, it will be given type RESULT_TYPE. */
2597 binary_op_error (code);
2598 return error_mark_node;
2603 if (TREE_TYPE (op0) != result_type)
2604 op0 = convert (result_type, op0);
2605 if (TREE_TYPE (op1) != result_type)
2606 op1 = convert (result_type, op1);
2609 if (build_type == NULL_TREE)
2610 build_type = result_type;
2613 register tree result = build (resultcode, build_type, op0, op1);
2614 register tree folded;
2616 folded = fold (result);
2617 if (folded == result)
2618 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2619 if (final_type != 0)
2620 return convert (final_type, folded);
2625 /* Return a tree for the sum or difference (RESULTCODE says which)
2626 of pointer PTROP and integer INTOP. */
2629 pointer_int_sum (resultcode, ptrop, intop)
2630 enum tree_code resultcode;
2631 register tree ptrop, intop;
2635 register tree result;
2636 register tree folded;
2638 /* The result is a pointer of the same type that is being added. */
2640 register tree result_type = TREE_TYPE (ptrop);
2642 if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
2644 if (pedantic || warn_pointer_arith)
2645 pedwarn ("pointer of type `void *' used in arithmetic");
2646 size_exp = integer_one_node;
2648 else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
2650 if (pedantic || warn_pointer_arith)
2651 pedwarn ("pointer to a function used in arithmetic");
2652 size_exp = integer_one_node;
2655 size_exp = c_size_in_bytes (TREE_TYPE (result_type));
2657 /* If what we are about to multiply by the size of the elements
2658 contains a constant term, apply distributive law
2659 and multiply that constant term separately.
2660 This helps produce common subexpressions. */
2662 if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
2663 && ! TREE_CONSTANT (intop)
2664 && TREE_CONSTANT (TREE_OPERAND (intop, 1))
2665 && TREE_CONSTANT (size_exp)
2666 /* If the constant comes from pointer subtraction,
2667 skip this optimization--it would cause an error. */
2668 && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE
2669 /* If the constant is unsigned, and smaller than the pointer size,
2670 then we must skip this optimization. This is because it could cause
2671 an overflow error if the constant is negative but INTOP is not. */
2672 && (! TREE_UNSIGNED (TREE_TYPE (intop))
2673 || (TYPE_PRECISION (TREE_TYPE (intop))
2674 == TYPE_PRECISION (TREE_TYPE (ptrop)))))
2676 enum tree_code subcode = resultcode;
2677 tree int_type = TREE_TYPE (intop);
2678 if (TREE_CODE (intop) == MINUS_EXPR)
2679 subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
2680 /* Convert both subexpression types to the type of intop,
2681 because weird cases involving pointer arithmetic
2682 can result in a sum or difference with different type args. */
2683 ptrop = build_binary_op (subcode, ptrop,
2684 convert (int_type, TREE_OPERAND (intop, 1)), 1);
2685 intop = convert (int_type, TREE_OPERAND (intop, 0));
2688 /* Convert the integer argument to a type the same size as sizetype
2689 so the multiply won't overflow spuriously. */
2691 if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype)
2692 || TREE_UNSIGNED (TREE_TYPE (intop)) != TREE_UNSIGNED (sizetype))
2693 intop = convert (type_for_size (TYPE_PRECISION (sizetype),
2694 TREE_UNSIGNED (sizetype)), intop);
2696 /* Replace the integer argument with a suitable product by the object size.
2697 Do this multiplication as signed, then convert to the appropriate
2698 pointer type (actually unsigned integral). */
2700 intop = convert (result_type,
2701 build_binary_op (MULT_EXPR, intop,
2702 convert (TREE_TYPE (intop), size_exp), 1));
2704 /* Create the sum or difference. */
2706 result = build (resultcode, result_type, ptrop, intop);
2708 folded = fold (result);
2709 if (folded == result)
2710 TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop);
2714 /* Return a tree for the difference of pointers OP0 and OP1.
2715 The resulting tree has type int. */
2718 pointer_diff (op0, op1)
2719 register tree op0, op1;
2721 register tree result, folded;
2722 tree restype = ptrdiff_type_node;
2724 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2726 if (pedantic || warn_pointer_arith)
2728 if (TREE_CODE (target_type) == VOID_TYPE)
2729 pedwarn ("pointer of type `void *' used in subtraction");
2730 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2731 pedwarn ("pointer to a function used in subtraction");
2734 /* First do the subtraction as integers;
2735 then drop through to build the divide operator.
2736 Do not do default conversions on the minus operator
2737 in case restype is a short type. */
2739 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2740 convert (restype, op1), 0);
2741 /* This generates an error if op1 is pointer to incomplete type. */
2742 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
2743 error ("arithmetic on pointer to an incomplete type");
2745 /* This generates an error if op0 is pointer to incomplete type. */
2746 op1 = c_size_in_bytes (target_type);
2748 /* Divide by the size, in easiest possible way. */
2750 result = build (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2752 folded = fold (result);
2753 if (folded == result)
2754 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2758 /* Construct and perhaps optimize a tree representation
2759 for a unary operation. CODE, a tree_code, specifies the operation
2760 and XARG is the operand. NOCONVERT nonzero suppresses
2761 the default promotions (such as from short to int). */
2764 build_unary_op (code, xarg, noconvert)
2765 enum tree_code code;
2769 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2770 register tree arg = xarg;
2771 register tree argtype = 0;
2772 register enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2775 if (typecode == ERROR_MARK)
2776 return error_mark_node;
2777 if (typecode == ENUMERAL_TYPE)
2778 typecode = INTEGER_TYPE;
2783 /* This is used for unary plus, because a CONVERT_EXPR
2784 is enough to prevent anybody from looking inside for
2785 associativity, but won't generate any code. */
2786 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2787 || typecode == COMPLEX_TYPE))
2789 error ("wrong type argument to unary plus");
2790 return error_mark_node;
2792 else if (!noconvert)
2793 arg = default_conversion (arg);
2797 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2798 || typecode == COMPLEX_TYPE))
2800 error ("wrong type argument to unary minus");
2801 return error_mark_node;
2803 else if (!noconvert)
2804 arg = default_conversion (arg);
2808 if (typecode == COMPLEX_TYPE)
2812 arg = default_conversion (arg);
2814 else if (typecode != INTEGER_TYPE)
2816 error ("wrong type argument to bit-complement");
2817 return error_mark_node;
2819 else if (!noconvert)
2820 arg = default_conversion (arg);
2824 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2825 || typecode == COMPLEX_TYPE))
2827 error ("wrong type argument to abs");
2828 return error_mark_node;
2830 else if (!noconvert)
2831 arg = default_conversion (arg);
2835 /* Conjugating a real value is a no-op, but allow it anyway. */
2836 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2837 || typecode == COMPLEX_TYPE))
2839 error ("wrong type argument to conjugation");
2840 return error_mark_node;
2842 else if (!noconvert)
2843 arg = default_conversion (arg);
2846 case TRUTH_NOT_EXPR:
2847 if (typecode != INTEGER_TYPE
2848 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2849 && typecode != COMPLEX_TYPE
2850 /* These will convert to a pointer. */
2851 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2853 error ("wrong type argument to unary exclamation mark");
2854 return error_mark_node;
2856 arg = truthvalue_conversion (arg);
2857 return invert_truthvalue (arg);
2863 if (TREE_CODE (arg) == COMPLEX_CST)
2864 return TREE_REALPART (arg);
2865 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2866 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2871 if (TREE_CODE (arg) == COMPLEX_CST)
2872 return TREE_IMAGPART (arg);
2873 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2874 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2876 return convert (TREE_TYPE (arg), integer_zero_node);
2878 case PREINCREMENT_EXPR:
2879 case POSTINCREMENT_EXPR:
2880 case PREDECREMENT_EXPR:
2881 case POSTDECREMENT_EXPR:
2882 /* Handle complex lvalues (when permitted)
2883 by reduction to simpler cases. */
2885 val = unary_complex_lvalue (code, arg);
2889 /* Increment or decrement the real part of the value,
2890 and don't change the imaginary part. */
2891 if (typecode == COMPLEX_TYPE)
2895 arg = stabilize_reference (arg);
2896 real = build_unary_op (REALPART_EXPR, arg, 1);
2897 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2898 return build (COMPLEX_EXPR, TREE_TYPE (arg),
2899 build_unary_op (code, real, 1), imag);
2902 /* Report invalid types. */
2904 if (typecode != POINTER_TYPE
2905 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2907 error ("wrong type argument to %s",
2908 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2909 ? "increment" : "decrement");
2910 return error_mark_node;
2915 tree result_type = TREE_TYPE (arg);
2917 arg = get_unwidened (arg, 0);
2918 argtype = TREE_TYPE (arg);
2920 /* Compute the increment. */
2922 if (typecode == POINTER_TYPE)
2924 /* If pointer target is an undefined struct,
2925 we just cannot know how to do the arithmetic. */
2926 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2927 error ("%s of pointer to unknown structure",
2928 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2929 ? "increment" : "decrement");
2930 else if ((pedantic || warn_pointer_arith)
2931 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2932 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2933 pedwarn ("wrong type argument to %s",
2934 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2935 ? "increment" : "decrement");
2936 inc = c_size_in_bytes (TREE_TYPE (result_type));
2939 inc = integer_one_node;
2941 inc = convert (argtype, inc);
2943 /* Handle incrementing a cast-expression. */
2946 switch (TREE_CODE (arg))
2951 case FIX_TRUNC_EXPR:
2952 case FIX_FLOOR_EXPR:
2953 case FIX_ROUND_EXPR:
2955 pedantic_lvalue_warning (CONVERT_EXPR);
2956 /* If the real type has the same machine representation
2957 as the type it is cast to, we can make better output
2958 by adding directly to the inside of the cast. */
2959 if ((TREE_CODE (TREE_TYPE (arg))
2960 == TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0))))
2961 && (TYPE_MODE (TREE_TYPE (arg))
2962 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (arg, 0)))))
2963 arg = TREE_OPERAND (arg, 0);
2966 tree incremented, modify, value;
2967 arg = stabilize_reference (arg);
2968 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
2971 value = save_expr (arg);
2972 incremented = build (((code == PREINCREMENT_EXPR
2973 || code == POSTINCREMENT_EXPR)
2974 ? PLUS_EXPR : MINUS_EXPR),
2975 argtype, value, inc);
2976 TREE_SIDE_EFFECTS (incremented) = 1;
2977 modify = build_modify_expr (arg, NOP_EXPR, incremented);
2978 value = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
2979 TREE_USED (value) = 1;
2989 /* Complain about anything else that is not a true lvalue. */
2990 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2991 || code == POSTINCREMENT_EXPR)
2992 ? "invalid lvalue in increment"
2993 : "invalid lvalue in decrement")))
2994 return error_mark_node;
2996 /* Report a read-only lvalue. */
2997 if (TREE_READONLY (arg))
2998 readonly_warning (arg,
2999 ((code == PREINCREMENT_EXPR
3000 || code == POSTINCREMENT_EXPR)
3001 ? "increment" : "decrement"));
3003 val = build (code, TREE_TYPE (arg), arg, inc);
3004 TREE_SIDE_EFFECTS (val) = 1;
3005 val = convert (result_type, val);
3006 if (TREE_CODE (val) != code)
3007 TREE_NO_UNUSED_WARNING (val) = 1;
3012 /* Note that this operation never does default_conversion
3013 regardless of NOCONVERT. */
3015 /* Let &* cancel out to simplify resulting code. */
3016 if (TREE_CODE (arg) == INDIRECT_REF)
3018 /* Don't let this be an lvalue. */
3019 if (lvalue_p (TREE_OPERAND (arg, 0)))
3020 return non_lvalue (TREE_OPERAND (arg, 0));
3021 return TREE_OPERAND (arg, 0);
3024 /* For &x[y], return x+y */
3025 if (TREE_CODE (arg) == ARRAY_REF)
3027 if (mark_addressable (TREE_OPERAND (arg, 0)) == 0)
3028 return error_mark_node;
3029 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
3030 TREE_OPERAND (arg, 1), 1);
3033 /* Handle complex lvalues (when permitted)
3034 by reduction to simpler cases. */
3035 val = unary_complex_lvalue (code, arg);
3039 #if 0 /* Turned off because inconsistent;
3040 float f; *&(int)f = 3.4 stores in int format
3041 whereas (int)f = 3.4 stores in float format. */
3042 /* Address of a cast is just a cast of the address
3043 of the operand of the cast. */
3044 switch (TREE_CODE (arg))
3049 case FIX_TRUNC_EXPR:
3050 case FIX_FLOOR_EXPR:
3051 case FIX_ROUND_EXPR:
3054 pedwarn ("ISO C forbids the address of a cast expression");
3055 return convert (build_pointer_type (TREE_TYPE (arg)),
3056 build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0),
3061 /* Allow the address of a constructor if all the elements
3063 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_CONSTANT (arg))
3065 /* Anything not already handled and not a true memory reference
3067 else if (typecode != FUNCTION_TYPE
3068 && !lvalue_or_else (arg, "invalid lvalue in unary `&'"))
3069 return error_mark_node;
3071 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3072 argtype = TREE_TYPE (arg);
3074 /* If the lvalue is const or volatile, merge that into the type
3075 to which the address will point. Note that you can't get a
3076 restricted pointer by taking the address of something, so we
3077 only have to deal with `const' and `volatile' here. */
3078 if ((DECL_P (arg) || TREE_CODE_CLASS (TREE_CODE (arg)) == 'r')
3079 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
3080 argtype = c_build_type_variant (argtype,
3081 TREE_READONLY (arg),
3082 TREE_THIS_VOLATILE (arg));
3084 argtype = build_pointer_type (argtype);
3086 if (mark_addressable (arg) == 0)
3087 return error_mark_node;
3092 if (TREE_CODE (arg) == COMPONENT_REF)
3094 tree field = TREE_OPERAND (arg, 1);
3096 addr = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
3098 if (DECL_C_BIT_FIELD (field))
3100 error ("attempt to take address of bit-field structure member `%s'",
3101 IDENTIFIER_POINTER (DECL_NAME (field)));
3102 return error_mark_node;
3105 addr = fold (build (PLUS_EXPR, argtype,
3106 convert (argtype, addr),
3107 convert (argtype, byte_position (field))));
3110 addr = build1 (code, argtype, arg);
3112 /* Address of a static or external variable or
3113 file-scope function counts as a constant. */
3115 && ! (TREE_CODE (arg) == FUNCTION_DECL
3116 && DECL_CONTEXT (arg) != 0))
3117 TREE_CONSTANT (addr) = 1;
3126 argtype = TREE_TYPE (arg);
3127 return fold (build1 (code, argtype, arg));
3131 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3132 convert ARG with the same conversions in the same order
3133 and return the result. */
3136 convert_sequence (conversions, arg)
3140 switch (TREE_CODE (conversions))
3145 case FIX_TRUNC_EXPR:
3146 case FIX_FLOOR_EXPR:
3147 case FIX_ROUND_EXPR:
3149 return convert (TREE_TYPE (conversions),
3150 convert_sequence (TREE_OPERAND (conversions, 0),
3159 /* Return nonzero if REF is an lvalue valid for this language.
3160 Lvalues can be assigned, unless their type has TYPE_READONLY.
3161 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3167 register enum tree_code code = TREE_CODE (ref);
3174 return lvalue_p (TREE_OPERAND (ref, 0));
3185 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3186 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3190 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3197 /* Return nonzero if REF is an lvalue valid for this language;
3198 otherwise, print an error message and return zero. */
3201 lvalue_or_else (ref, msgid)
3205 int win = lvalue_p (ref);
3208 error ("%s", msgid);
3213 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3214 for certain kinds of expressions which are not really lvalues
3215 but which we can accept as lvalues.
3217 If ARG is not a kind of expression we can handle, return zero. */
3220 unary_complex_lvalue (code, arg)
3221 enum tree_code code;
3224 /* Handle (a, b) used as an "lvalue". */
3225 if (TREE_CODE (arg) == COMPOUND_EXPR)
3227 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
3229 /* If this returns a function type, it isn't really being used as
3230 an lvalue, so don't issue a warning about it. */
3231 if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE)
3232 pedantic_lvalue_warning (COMPOUND_EXPR);
3234 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
3235 TREE_OPERAND (arg, 0), real_result);
3238 /* Handle (a ? b : c) used as an "lvalue". */
3239 if (TREE_CODE (arg) == COND_EXPR)
3241 pedantic_lvalue_warning (COND_EXPR);
3242 if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE)
3243 pedantic_lvalue_warning (COMPOUND_EXPR);
3245 return (build_conditional_expr
3246 (TREE_OPERAND (arg, 0),
3247 build_unary_op (code, TREE_OPERAND (arg, 1), 0),
3248 build_unary_op (code, TREE_OPERAND (arg, 2), 0)));
3254 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3255 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3258 pedantic_lvalue_warning (code)
3259 enum tree_code code;
3265 pedwarn ("ISO C forbids use of conditional expressions as lvalues");
3268 pedwarn ("ISO C forbids use of compound expressions as lvalues");
3271 pedwarn ("ISO C forbids use of cast expressions as lvalues");
3276 /* Warn about storing in something that is `const'. */
3279 readonly_warning (arg, msgid)
3283 /* Forbid assignments to iterators. */
3284 if (TREE_CODE (arg) == VAR_DECL && ITERATOR_P (arg))
3285 pedwarn ("%s of iterator `%s'", _(msgid),
3286 IDENTIFIER_POINTER (DECL_NAME (arg)));
3288 if (TREE_CODE (arg) == COMPONENT_REF)
3290 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3291 readonly_warning (TREE_OPERAND (arg, 0), msgid);
3293 pedwarn ("%s of read-only member `%s'", _(msgid),
3294 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1))));
3296 else if (TREE_CODE (arg) == VAR_DECL)
3297 pedwarn ("%s of read-only variable `%s'", _(msgid),
3298 IDENTIFIER_POINTER (DECL_NAME (arg)));
3300 pedwarn ("%s of read-only location", _(msgid));
3303 /* Mark EXP saying that we need to be able to take the
3304 address of it; it should not be allocated in a register.
3305 Value is 1 if successful. */
3308 mark_addressable (exp)
3311 register tree x = exp;
3313 switch (TREE_CODE (x))
3316 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3318 error ("cannot take address of bitfield `%s'",
3319 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (x, 1))));
3323 /* ... fall through ... */
3329 x = TREE_OPERAND (x, 0);
3333 TREE_ADDRESSABLE (x) = 1;
3340 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
3341 && DECL_NONLOCAL (x))
3343 if (TREE_PUBLIC (x))
3345 error ("global register variable `%s' used in nested function",
3346 IDENTIFIER_POINTER (DECL_NAME (x)));
3349 pedwarn ("register variable `%s' used in nested function",
3350 IDENTIFIER_POINTER (DECL_NAME (x)));
3352 else if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x))
3354 if (TREE_PUBLIC (x))
3356 error ("address of global register variable `%s' requested",
3357 IDENTIFIER_POINTER (DECL_NAME (x)));
3361 /* If we are making this addressable due to its having
3362 volatile components, give a different error message. Also
3363 handle the case of an unnamed parameter by not trying
3364 to give the name. */
3366 else if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (x)))
3368 error ("cannot put object with volatile field into register");
3372 pedwarn ("address of register variable `%s' requested",
3373 IDENTIFIER_POINTER (DECL_NAME (x)));
3375 put_var_into_stack (x);
3379 TREE_ADDRESSABLE (x) = 1;
3380 #if 0 /* poplevel deals with this now. */
3381 if (DECL_CONTEXT (x) == 0)
3382 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
3390 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3393 build_conditional_expr (ifexp, op1, op2)
3394 tree ifexp, op1, op2;
3396 register tree type1;
3397 register tree type2;
3398 register enum tree_code code1;
3399 register enum tree_code code2;
3400 register tree result_type = NULL;
3401 tree orig_op1 = op1, orig_op2 = op2;
3403 ifexp = truthvalue_conversion (default_conversion (ifexp));
3405 #if 0 /* Produces wrong result if within sizeof. */
3406 /* Don't promote the operands separately if they promote
3407 the same way. Return the unpromoted type and let the combined
3408 value get promoted if necessary. */
3410 if (TREE_TYPE (op1) == TREE_TYPE (op2)
3411 && TREE_CODE (TREE_TYPE (op1)) != ARRAY_TYPE
3412 && TREE_CODE (TREE_TYPE (op1)) != ENUMERAL_TYPE
3413 && TREE_CODE (TREE_TYPE (op1)) != FUNCTION_TYPE)
3415 if (TREE_CODE (ifexp) == INTEGER_CST)
3416 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3418 return fold (build (COND_EXPR, TREE_TYPE (op1), ifexp, op1, op2));
3422 /* Promote both alternatives. */
3424 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3425 op1 = default_conversion (op1);
3426 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3427 op2 = default_conversion (op2);
3429 if (TREE_CODE (ifexp) == ERROR_MARK
3430 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3431 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3432 return error_mark_node;
3434 type1 = TREE_TYPE (op1);
3435 code1 = TREE_CODE (type1);
3436 type2 = TREE_TYPE (op2);
3437 code2 = TREE_CODE (type2);
3439 /* Quickly detect the usual case where op1 and op2 have the same type
3441 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3444 result_type = type1;
3446 result_type = TYPE_MAIN_VARIANT (type1);
3448 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3449 || code1 == COMPLEX_TYPE)
3450 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3451 || code2 == COMPLEX_TYPE))
3453 result_type = common_type (type1, type2);
3455 /* If -Wsign-compare, warn here if type1 and type2 have
3456 different signedness. We'll promote the signed to unsigned
3457 and later code won't know it used to be different.
3458 Do this check on the original types, so that explicit casts
3459 will be considered, but default promotions won't. */
3460 if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare)
3461 && !skip_evaluation)
3463 int unsigned_op1 = TREE_UNSIGNED (TREE_TYPE (orig_op1));
3464 int unsigned_op2 = TREE_UNSIGNED (TREE_TYPE (orig_op2));
3466 if (unsigned_op1 ^ unsigned_op2)
3468 /* Do not warn if the result type is signed, since the
3469 signed type will only be chosen if it can represent
3470 all the values of the unsigned type. */
3471 if (! TREE_UNSIGNED (result_type))
3473 /* Do not warn if the signed quantity is an unsuffixed
3474 integer literal (or some static constant expression
3475 involving such literals) and it is non-negative. */
3476 else if ((unsigned_op2 && tree_expr_nonnegative_p (op1))
3477 || (unsigned_op1 && tree_expr_nonnegative_p (op2)))
3480 warning ("signed and unsigned type in conditional expression");
3484 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3486 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3487 pedwarn ("ISO C forbids conditional expr with only one void side");
3488 result_type = void_type_node;
3490 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3492 if (comp_target_types (type1, type2))
3493 result_type = common_type (type1, type2);
3494 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
3495 && TREE_CODE (orig_op1) != NOP_EXPR)
3496 result_type = qualify_type (type2, type1);
3497 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
3498 && TREE_CODE (orig_op2) != NOP_EXPR)
3499 result_type = qualify_type (type1, type2);
3500 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3502 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3503 pedwarn ("ISO C forbids conditional expr between `void *' and function pointer");
3504 result_type = qualify_type (type1, type2);
3506 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3508 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3509 pedwarn ("ISO C forbids conditional expr between `void *' and function pointer");
3510 result_type = qualify_type (type2, type1);
3514 pedwarn ("pointer type mismatch in conditional expression");
3515 result_type = build_pointer_type (void_type_node);
3518 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3520 if (! integer_zerop (op2))
3521 pedwarn ("pointer/integer type mismatch in conditional expression");
3524 op2 = null_pointer_node;
3525 #if 0 /* The spec seems to say this is permitted. */
3526 if (pedantic && TREE_CODE (type1) == FUNCTION_TYPE)
3527 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3530 result_type = type1;
3532 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3534 if (!integer_zerop (op1))
3535 pedwarn ("pointer/integer type mismatch in conditional expression");
3538 op1 = null_pointer_node;
3539 #if 0 /* The spec seems to say this is permitted. */
3540 if (pedantic && TREE_CODE (type2) == FUNCTION_TYPE)
3541 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3544 result_type = type2;
3549 if (flag_cond_mismatch)
3550 result_type = void_type_node;
3553 error ("type mismatch in conditional expression");
3554 return error_mark_node;
3558 /* Merge const and volatile flags of the incoming types. */
3560 = build_type_variant (result_type,
3561 TREE_READONLY (op1) || TREE_READONLY (op2),
3562 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3564 if (result_type != TREE_TYPE (op1))
3565 op1 = convert_and_check (result_type, op1);
3566 if (result_type != TREE_TYPE (op2))
3567 op2 = convert_and_check (result_type, op2);
3569 if (TREE_CODE (ifexp) == INTEGER_CST)
3570 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3572 return fold (build (COND_EXPR, result_type, ifexp, op1, op2));
3575 /* Given a list of expressions, return a compound expression
3576 that performs them all and returns the value of the last of them. */
3579 build_compound_expr (list)
3582 return internal_build_compound_expr (list, TRUE);
3586 internal_build_compound_expr (list, first_p)
3592 if (TREE_CHAIN (list) == 0)
3594 #if 0 /* If something inside inhibited lvalueness, we should not override. */
3595 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3597 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3598 if (TREE_CODE (list) == NON_LVALUE_EXPR)
3599 list = TREE_OPERAND (list, 0);
3602 /* Don't let (0, 0) be null pointer constant. */
3603 if (!first_p && integer_zerop (TREE_VALUE (list)))
3604 return non_lvalue (TREE_VALUE (list));
3605 return TREE_VALUE (list);
3608 if (TREE_CHAIN (list) != 0 && TREE_CHAIN (TREE_CHAIN (list)) == 0)
3610 /* Convert arrays to pointers when there really is a comma operator. */
3611 if (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (list)))) == ARRAY_TYPE)
3612 TREE_VALUE (TREE_CHAIN (list))
3613 = default_conversion (TREE_VALUE (TREE_CHAIN (list)));
3616 rest = internal_build_compound_expr (TREE_CHAIN (list), FALSE);
3618 if (! TREE_SIDE_EFFECTS (TREE_VALUE (list)))
3620 /* The left-hand operand of a comma expression is like an expression
3621 statement: with -W or -Wunused, we should warn if it doesn't have
3622 any side-effects, unless it was explicitly cast to (void). */
3623 if ((extra_warnings || warn_unused_value)
3624 && ! (TREE_CODE (TREE_VALUE (list)) == CONVERT_EXPR
3625 && VOID_TYPE_P (TREE_TYPE (TREE_VALUE (list)))))
3626 warning ("left-hand operand of comma expression has no effect");
3628 /* When pedantic, a compound expression can be neither an lvalue
3629 nor an integer constant expression. */
3634 /* With -Wunused, we should also warn if the left-hand operand does have
3635 side-effects, but computes a value which is not used. For example, in
3636 `foo() + bar(), baz()' the result of the `+' operator is not used,
3637 so we should issue a warning. */
3638 else if (warn_unused_value)
3639 warn_if_unused_value (TREE_VALUE (list));
3641 return build (COMPOUND_EXPR, TREE_TYPE (rest), TREE_VALUE (list), rest);
3644 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3647 build_c_cast (type, expr)
3651 register tree value = expr;
3653 if (type == error_mark_node || expr == error_mark_node)
3654 return error_mark_node;
3655 type = TYPE_MAIN_VARIANT (type);
3658 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3659 if (TREE_CODE (value) == NON_LVALUE_EXPR)
3660 value = TREE_OPERAND (value, 0);
3663 if (TREE_CODE (type) == ARRAY_TYPE)
3665 error ("cast specifies array type");
3666 return error_mark_node;
3669 if (TREE_CODE (type) == FUNCTION_TYPE)
3671 error ("cast specifies function type");
3672 return error_mark_node;
3675 if (type == TREE_TYPE (value))
3679 if (TREE_CODE (type) == RECORD_TYPE
3680 || TREE_CODE (type) == UNION_TYPE)
3681 pedwarn ("ISO C forbids casting nonscalar to the same type");
3684 else if (TREE_CODE (type) == UNION_TYPE)
3687 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
3688 || TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE)
3689 value = default_conversion (value);
3691 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3692 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3693 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3702 pedwarn ("ISO C forbids casts to union type");
3703 if (TYPE_NAME (type) != 0)
3705 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
3706 name = IDENTIFIER_POINTER (TYPE_NAME (type));
3708 name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));
3712 t = digest_init (type, build (CONSTRUCTOR, type, NULL_TREE,
3713 build_tree_list (field, value)),
3715 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3718 error ("cast to union type from type not present in union");
3719 return error_mark_node;
3725 /* If casting to void, avoid the error that would come
3726 from default_conversion in the case of a non-lvalue array. */
3727 if (type == void_type_node)
3728 return build1 (CONVERT_EXPR, type, value);
3730 /* Convert functions and arrays to pointers,
3731 but don't convert any other types. */
3732 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
3733 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE)
3734 value = default_conversion (value);
3735 otype = TREE_TYPE (value);
3737 /* Optionally warn about potentially worrisome casts. */
3740 && TREE_CODE (type) == POINTER_TYPE
3741 && TREE_CODE (otype) == POINTER_TYPE)
3743 tree in_type = type;
3744 tree in_otype = otype;
3747 /* Check that the qualifiers on IN_TYPE are a superset of
3748 the qualifiers of IN_OTYPE. The outermost level of
3749 POINTER_TYPE nodes is uninteresting and we stop as soon
3750 as we hit a non-POINTER_TYPE node on either type. */
3753 in_otype = TREE_TYPE (in_otype);
3754 in_type = TREE_TYPE (in_type);
3755 warn |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3757 while (TREE_CODE (in_type) == POINTER_TYPE
3758 && TREE_CODE (in_otype) == POINTER_TYPE);
3761 /* There are qualifiers present in IN_OTYPE that are not
3762 present in IN_TYPE. */
3763 warning ("cast discards qualifiers from pointer target type");
3766 /* Warn about possible alignment problems. */
3767 if (STRICT_ALIGNMENT && warn_cast_align
3768 && TREE_CODE (type) == POINTER_TYPE
3769 && TREE_CODE (otype) == POINTER_TYPE
3770 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3771 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3772 /* Don't warn about opaque types, where the actual alignment
3773 restriction is unknown. */
3774 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3775 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3776 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3777 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3778 warning ("cast increases required alignment of target type");
3780 if (TREE_CODE (type) == INTEGER_TYPE
3781 && TREE_CODE (otype) == POINTER_TYPE
3782 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3783 && !TREE_CONSTANT (value))
3784 warning ("cast from pointer to integer of different size");
3786 if (warn_bad_function_cast
3787 && TREE_CODE (value) == CALL_EXPR
3788 && TREE_CODE (type) != TREE_CODE (otype))
3789 warning ("cast does not match function type");
3791 if (TREE_CODE (type) == POINTER_TYPE
3792 && TREE_CODE (otype) == INTEGER_TYPE
3793 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3794 /* Don't warn about converting any constant. */
3795 && !TREE_CONSTANT (value))
3796 warning ("cast to pointer from integer of different size");
3799 value = convert (type, value);
3801 /* Ignore any integer overflow caused by the cast. */
3802 if (TREE_CODE (value) == INTEGER_CST)
3804 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3805 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3809 /* Pedantically, don't ley (void *) (FOO *) 0 be a null pointer constant. */
3810 if (pedantic && TREE_CODE (value) == INTEGER_CST
3811 && TREE_CODE (expr) == INTEGER_CST
3812 && TREE_CODE (TREE_TYPE (expr)) != INTEGER_TYPE)
3813 value = non_lvalue (value);
3815 /* If pedantic, don't let a cast be an lvalue. */
3816 if (value == expr && pedantic)
3817 value = non_lvalue (value);
3822 /* Build an assignment expression of lvalue LHS from value RHS.
3823 MODIFYCODE is the code for a binary operator that we use
3824 to combine the old value of LHS with RHS to get the new value.
3825 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3828 build_modify_expr (lhs, modifycode, rhs)
3830 enum tree_code modifycode;
3832 register tree result;
3834 tree lhstype = TREE_TYPE (lhs);
3835 tree olhstype = lhstype;
3837 /* Types that aren't fully specified cannot be used in assignments. */
3838 lhs = require_complete_type (lhs);
3840 /* Avoid duplicate error messages from operands that had errors. */
3841 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3842 return error_mark_node;
3844 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3845 /* Do not use STRIP_NOPS here. We do not want an enumerator
3846 whose value is 0 to count as a null pointer constant. */
3847 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3848 rhs = TREE_OPERAND (rhs, 0);
3852 /* Handle control structure constructs used as "lvalues". */
3854 switch (TREE_CODE (lhs))
3856 /* Handle (a, b) used as an "lvalue". */
3858 pedantic_lvalue_warning (COMPOUND_EXPR);
3859 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1), modifycode, rhs);
3860 if (TREE_CODE (newrhs) == ERROR_MARK)
3861 return error_mark_node;
3862 return build (COMPOUND_EXPR, lhstype,
3863 TREE_OPERAND (lhs, 0), newrhs);
3865 /* Handle (a ? b : c) used as an "lvalue". */
3867 pedantic_lvalue_warning (COND_EXPR);
3868 rhs = save_expr (rhs);
3870 /* Produce (a ? (b = rhs) : (c = rhs))
3871 except that the RHS goes through a save-expr
3872 so the code to compute it is only emitted once. */
3874 = build_conditional_expr (TREE_OPERAND (lhs, 0),
3875 build_modify_expr (TREE_OPERAND (lhs, 1),
3877 build_modify_expr (TREE_OPERAND (lhs, 2),
3879 if (TREE_CODE (cond) == ERROR_MARK)
3881 /* Make sure the code to compute the rhs comes out
3882 before the split. */
3883 return build (COMPOUND_EXPR, TREE_TYPE (lhs),
3884 /* But cast it to void to avoid an "unused" error. */
3885 convert (void_type_node, rhs), cond);
3891 /* If a binary op has been requested, combine the old LHS value with the RHS
3892 producing the value we should actually store into the LHS. */
3894 if (modifycode != NOP_EXPR)
3896 lhs = stabilize_reference (lhs);
3897 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3900 /* Handle a cast used as an "lvalue".
3901 We have already performed any binary operator using the value as cast.
3902 Now convert the result to the cast type of the lhs,
3903 and then true type of the lhs and store it there;
3904 then convert result back to the cast type to be the value
3905 of the assignment. */
3907 switch (TREE_CODE (lhs))
3912 case FIX_TRUNC_EXPR:
3913 case FIX_FLOOR_EXPR:
3914 case FIX_ROUND_EXPR:
3916 if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
3917 || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE)
3918 newrhs = default_conversion (newrhs);
3920 tree inner_lhs = TREE_OPERAND (lhs, 0);
3922 result = build_modify_expr (inner_lhs, NOP_EXPR,
3923 convert (TREE_TYPE (inner_lhs),
3924 convert (lhstype, newrhs)));
3925 if (TREE_CODE (result) == ERROR_MARK)
3927 pedantic_lvalue_warning (CONVERT_EXPR);
3928 return convert (TREE_TYPE (lhs), result);
3935 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3936 Reject anything strange now. */
3938 if (!lvalue_or_else (lhs, "invalid lvalue in assignment"))
3939 return error_mark_node;
3941 /* Warn about storing in something that is `const'. */
3943 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3944 || ((TREE_CODE (lhstype) == RECORD_TYPE
3945 || TREE_CODE (lhstype) == UNION_TYPE)
3946 && C_TYPE_FIELDS_READONLY (lhstype)))
3947 readonly_warning (lhs, "assignment");
3949 /* If storing into a structure or union member,
3950 it has probably been given type `int'.
3951 Compute the type that would go with
3952 the actual amount of storage the member occupies. */
3954 if (TREE_CODE (lhs) == COMPONENT_REF
3955 && (TREE_CODE (lhstype) == INTEGER_TYPE
3956 || TREE_CODE (lhstype) == REAL_TYPE
3957 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3958 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3960 /* If storing in a field that is in actuality a short or narrower than one,
3961 we must store in the field in its actual type. */
3963 if (lhstype != TREE_TYPE (lhs))
3965 lhs = copy_node (lhs);
3966 TREE_TYPE (lhs) = lhstype;
3969 /* Convert new value to destination type. */
3971 newrhs = convert_for_assignment (lhstype, newrhs, _("assignment"),
3972 NULL_TREE, NULL_TREE, 0);
3973 if (TREE_CODE (newrhs) == ERROR_MARK)
3974 return error_mark_node;
3976 result = build (MODIFY_EXPR, lhstype, lhs, newrhs);
3977 TREE_SIDE_EFFECTS (result) = 1;
3979 /* If we got the LHS in a different type for storing in,
3980 convert the result back to the nominal type of LHS
3981 so that the value we return always has the same type
3982 as the LHS argument. */
3984 if (olhstype == TREE_TYPE (result))
3986 return convert_for_assignment (olhstype, result, _("assignment"),
3987 NULL_TREE, NULL_TREE, 0);
3990 /* Convert value RHS to type TYPE as preparation for an assignment
3991 to an lvalue of type TYPE.
3992 The real work of conversion is done by `convert'.
3993 The purpose of this function is to generate error messages
3994 for assignments that are not allowed in C.
3995 ERRTYPE is a string to use in error messages:
3996 "assignment", "return", etc. If it is null, this is parameter passing
3997 for a function call (and different error messages are output).
3999 FUNNAME is the name of the function being called,
4000 as an IDENTIFIER_NODE, or null.
4001 PARMNUM is the number of the argument, for printing in error messages. */
4004 convert_for_assignment (type, rhs, errtype, fundecl, funname, parmnum)
4006 const char *errtype;
4007 tree fundecl, funname;
4010 register enum tree_code codel = TREE_CODE (type);
4011 register tree rhstype;
4012 register enum tree_code coder;
4014 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4015 /* Do not use STRIP_NOPS here. We do not want an enumerator
4016 whose value is 0 to count as a null pointer constant. */
4017 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
4018 rhs = TREE_OPERAND (rhs, 0);
4020 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
4021 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
4022 rhs = default_conversion (rhs);
4023 else if (optimize && TREE_CODE (rhs) == VAR_DECL)
4024 rhs = decl_constant_value (rhs);
4026 rhstype = TREE_TYPE (rhs);
4027 coder = TREE_CODE (rhstype);
4029 if (coder == ERROR_MARK)
4030 return error_mark_node;
4032 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
4034 overflow_warning (rhs);
4035 /* Check for Objective-C protocols. This will issue a warning if
4036 there are protocol violations. No need to use the return value. */
4037 maybe_objc_comptypes (type, rhstype, 0);
4041 if (coder == VOID_TYPE)
4043 error ("void value not ignored as it ought to be");
4044 return error_mark_node;
4046 /* A type converts to a reference to it.
4047 This code doesn't fully support references, it's just for the
4048 special case of va_start and va_copy. */
4049 if (codel == REFERENCE_TYPE
4050 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
4052 if (mark_addressable (rhs) == 0)
4053 return error_mark_node;
4054 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
4056 /* We already know that these two types are compatible, but they
4057 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4058 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4059 likely to be va_list, a typedef to __builtin_va_list, which
4060 is different enough that it will cause problems later. */
4061 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
4062 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
4064 rhs = build1 (NOP_EXPR, type, rhs);
4067 /* Arithmetic types all interconvert, and enum is treated like int. */
4068 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
4069 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE)
4070 && (coder == INTEGER_TYPE || coder == REAL_TYPE
4071 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE))
4072 return convert_and_check (type, rhs);
4074 /* Conversion to a transparent union from its member types.
4075 This applies only to function arguments. */
4076 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type) && ! errtype)
4079 tree marginal_memb_type = 0;
4081 for (memb_types = TYPE_FIELDS (type); memb_types;
4082 memb_types = TREE_CHAIN (memb_types))
4084 tree memb_type = TREE_TYPE (memb_types);
4086 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
4087 TYPE_MAIN_VARIANT (rhstype)))
4090 if (TREE_CODE (memb_type) != POINTER_TYPE)
4093 if (coder == POINTER_TYPE)
4095 register tree ttl = TREE_TYPE (memb_type);
4096 register tree ttr = TREE_TYPE (rhstype);
4098 /* Any non-function converts to a [const][volatile] void *
4099 and vice versa; otherwise, targets must be the same.
4100 Meanwhile, the lhs target must have all the qualifiers of
4102 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4103 || comp_target_types (memb_type, rhstype))
4105 /* If this type won't generate any warnings, use it. */
4106 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
4107 || ((TREE_CODE (ttr) == FUNCTION_TYPE
4108 && TREE_CODE (ttl) == FUNCTION_TYPE)
4109 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
4110 == TYPE_QUALS (ttr))
4111 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
4112 == TYPE_QUALS (ttl))))
4115 /* Keep looking for a better type, but remember this one. */
4116 if (! marginal_memb_type)
4117 marginal_memb_type = memb_type;
4121 /* Can convert integer zero to any pointer type. */
4122 if (integer_zerop (rhs)
4123 || (TREE_CODE (rhs) == NOP_EXPR
4124 && integer_zerop (TREE_OPERAND (rhs, 0))))
4126 rhs = null_pointer_node;
4131 if (memb_types || marginal_memb_type)
4135 /* We have only a marginally acceptable member type;
4136 it needs a warning. */
4137 register tree ttl = TREE_TYPE (marginal_memb_type);
4138 register tree ttr = TREE_TYPE (rhstype);
4140 /* Const and volatile mean something different for function
4141 types, so the usual warnings are not appropriate. */
4142 if (TREE_CODE (ttr) == FUNCTION_TYPE
4143 && TREE_CODE (ttl) == FUNCTION_TYPE)
4145 /* Because const and volatile on functions are
4146 restrictions that say the function will not do
4147 certain things, it is okay to use a const or volatile
4148 function where an ordinary one is wanted, but not
4150 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4151 warn_for_assignment ("%s makes qualified function pointer from unqualified",
4152 errtype, funname, parmnum);
4154 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4155 warn_for_assignment ("%s discards qualifiers from pointer target type",
4160 if (pedantic && ! DECL_IN_SYSTEM_HEADER (fundecl))
4161 pedwarn ("ISO C prohibits argument conversion to union type");
4163 return build1 (NOP_EXPR, type, rhs);
4167 /* Conversions among pointers */
4168 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
4169 && (coder == POINTER_TYPE || coder == REFERENCE_TYPE))
4171 register tree ttl = TREE_TYPE (type);
4172 register tree ttr = TREE_TYPE (rhstype);
4174 /* Any non-function converts to a [const][volatile] void *
4175 and vice versa; otherwise, targets must be the same.
4176 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4177 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4178 || comp_target_types (type, rhstype)
4179 || (unsigned_type (TYPE_MAIN_VARIANT (ttl))
4180 == unsigned_type (TYPE_MAIN_VARIANT (ttr))))
4183 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
4186 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4187 which are not ANSI null ptr constants. */
4188 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
4189 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4190 warn_for_assignment ("ISO C forbids %s between function pointer and `void *'",
4191 errtype, funname, parmnum);
4192 /* Const and volatile mean something different for function types,
4193 so the usual warnings are not appropriate. */
4194 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4195 && TREE_CODE (ttl) != FUNCTION_TYPE)
4197 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4198 warn_for_assignment ("%s discards qualifiers from pointer target type",
4199 errtype, funname, parmnum);
4200 /* If this is not a case of ignoring a mismatch in signedness,
4202 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4203 || comp_target_types (type, rhstype))
4205 /* If there is a mismatch, do warn. */
4207 warn_for_assignment ("pointer targets in %s differ in signedness",
4208 errtype, funname, parmnum);
4210 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4211 && TREE_CODE (ttr) == FUNCTION_TYPE)
4213 /* Because const and volatile on functions are restrictions
4214 that say the function will not do certain things,
4215 it is okay to use a const or volatile function
4216 where an ordinary one is wanted, but not vice-versa. */
4217 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4218 warn_for_assignment ("%s makes qualified function pointer from unqualified",
4219 errtype, funname, parmnum);
4223 warn_for_assignment ("%s from incompatible pointer type",
4224 errtype, funname, parmnum);
4225 return convert (type, rhs);
4227 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4229 /* An explicit constant 0 can convert to a pointer,
4230 or one that results from arithmetic, even including
4231 a cast to integer type. */
4232 if (! (TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
4234 ! (TREE_CODE (rhs) == NOP_EXPR
4235 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
4236 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
4237 && integer_zerop (TREE_OPERAND (rhs, 0))))
4239 warn_for_assignment ("%s makes pointer from integer without a cast",
4240 errtype, funname, parmnum);
4241 return convert (type, rhs);
4243 return null_pointer_node;
4245 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4247 warn_for_assignment ("%s makes integer from pointer without a cast",
4248 errtype, funname, parmnum);
4249 return convert (type, rhs);
4256 tree selector = maybe_building_objc_message_expr ();
4258 if (selector && parmnum > 2)
4259 error ("incompatible type for argument %d of `%s'",
4260 parmnum - 2, IDENTIFIER_POINTER (selector));
4262 error ("incompatible type for argument %d of `%s'",
4263 parmnum, IDENTIFIER_POINTER (funname));
4266 error ("incompatible type for argument %d of indirect function call",
4270 error ("incompatible types in %s", errtype);
4272 return error_mark_node;
4275 /* Print a warning using MSGID.
4276 It gets OPNAME as its one parameter.
4277 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4278 FUNCTION and ARGNUM are handled specially if we are building an
4279 Objective-C selector. */
4282 warn_for_assignment (msgid, opname, function, argnum)
4290 tree selector = maybe_building_objc_message_expr ();
4293 if (selector && argnum > 2)
4295 function = selector;
4300 /* Function name is known; supply it. */
4301 const char *argstring = _("passing arg %d of `%s'");
4302 new_opname = (char *) alloca (IDENTIFIER_LENGTH (function)
4303 + strlen (argstring) + 1 + 25
4305 sprintf (new_opname, argstring, argnum,
4306 IDENTIFIER_POINTER (function));
4310 /* Function name unknown (call through ptr); just give arg number.*/
4311 const char *argnofun = _("passing arg %d of pointer to function");
4312 new_opname = (char *) alloca (strlen (argnofun) + 1 + 25 /*%d*/ + 1);
4313 sprintf (new_opname, argnofun, argnum);
4315 opname = new_opname;
4317 pedwarn (msgid, opname);
4320 /* If VALUE is a compound expr all of whose expressions are constant, then
4321 return its value. Otherwise, return error_mark_node.
4323 This is for handling COMPOUND_EXPRs as initializer elements
4324 which is allowed with a warning when -pedantic is specified. */
4327 valid_compound_expr_initializer (value, endtype)
4331 if (TREE_CODE (value) == COMPOUND_EXPR)
4333 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4335 return error_mark_node;
4336 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4339 else if (! TREE_CONSTANT (value)
4340 && ! initializer_constant_valid_p (value, endtype))
4341 return error_mark_node;
4346 /* Perform appropriate conversions on the initial value of a variable,
4347 store it in the declaration DECL,
4348 and print any error messages that are appropriate.
4349 If the init is invalid, store an ERROR_MARK. */
4352 store_init_value (decl, init)
4355 register tree value, type;
4357 /* If variable's type was invalidly declared, just ignore it. */
4359 type = TREE_TYPE (decl);
4360 if (TREE_CODE (type) == ERROR_MARK)
4363 /* Digest the specified initializer into an expression. */
4365 value = digest_init (type, init, TREE_STATIC (decl),
4366 TREE_STATIC (decl) || pedantic);
4368 /* Store the expression if valid; else report error. */
4371 /* Note that this is the only place we can detect the error
4372 in a case such as struct foo bar = (struct foo) { x, y };
4373 where there is one initial value which is a constructor expression. */
4374 if (value == error_mark_node)
4376 else if (TREE_STATIC (decl) && ! TREE_CONSTANT (value))
4378 error ("initializer for static variable is not constant");
4379 value = error_mark_node;
4381 else if (TREE_STATIC (decl)
4382 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
4384 error ("initializer for static variable uses complicated arithmetic");
4385 value = error_mark_node;
4389 if (pedantic && TREE_CODE (value) == CONSTRUCTOR)
4391 if (! TREE_CONSTANT (value))
4392 pedwarn ("aggregate initializer is not constant");
4393 else if (! TREE_STATIC (value))
4394 pedwarn ("aggregate initializer uses complicated arithmetic");
4399 if (warn_traditional
4400 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && ! TREE_STATIC (decl))
4401 warning ("traditional C rejects automatic aggregate initialization");
4403 DECL_INITIAL (decl) = value;
4405 /* ANSI wants warnings about out-of-range constant initializers. */
4406 STRIP_TYPE_NOPS (value);
4407 constant_expression_warning (value);
4410 /* Methods for storing and printing names for error messages. */
4412 /* Implement a spelling stack that allows components of a name to be pushed
4413 and popped. Each element on the stack is this structure. */
4425 #define SPELLING_STRING 1
4426 #define SPELLING_MEMBER 2
4427 #define SPELLING_BOUNDS 3
4429 static struct spelling *spelling; /* Next stack element (unused). */
4430 static struct spelling *spelling_base; /* Spelling stack base. */
4431 static int spelling_size; /* Size of the spelling stack. */
4433 /* Macros to save and restore the spelling stack around push_... functions.
4434 Alternative to SAVE_SPELLING_STACK. */
4436 #define SPELLING_DEPTH() (spelling - spelling_base)
4437 #define RESTORE_SPELLING_DEPTH(depth) (spelling = spelling_base + depth)
4439 /* Save and restore the spelling stack around arbitrary C code. */
4441 #define SAVE_SPELLING_DEPTH(code) \
4443 int __depth = SPELLING_DEPTH (); \
4445 RESTORE_SPELLING_DEPTH (__depth); \
4448 /* Push an element on the spelling stack with type KIND and assign VALUE
4451 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4453 int depth = SPELLING_DEPTH (); \
4455 if (depth >= spelling_size) \
4457 spelling_size += 10; \
4458 if (spelling_base == 0) \
4460 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4463 = (struct spelling *) xrealloc (spelling_base, \
4464 spelling_size * sizeof (struct spelling)); \
4465 RESTORE_SPELLING_DEPTH (depth); \
4468 spelling->kind = (KIND); \
4469 spelling->MEMBER = (VALUE); \
4473 /* Push STRING on the stack. Printed literally. */
4476 push_string (string)
4479 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4482 /* Push a member name on the stack. Printed as '.' STRING. */
4485 push_member_name (decl)
4490 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4491 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4494 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4497 push_array_bounds (bounds)
4500 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4503 /* Compute the maximum size in bytes of the printed spelling. */
4508 register int size = 0;
4509 register struct spelling *p;
4511 for (p = spelling_base; p < spelling; p++)
4513 if (p->kind == SPELLING_BOUNDS)
4516 size += strlen (p->u.s) + 1;
4522 /* Print the spelling to BUFFER and return it. */
4525 print_spelling (buffer)
4526 register char *buffer;
4528 register char *d = buffer;
4529 register struct spelling *p;
4531 for (p = spelling_base; p < spelling; p++)
4532 if (p->kind == SPELLING_BOUNDS)
4534 sprintf (d, "[%d]", p->u.i);
4539 register const char *s;
4540 if (p->kind == SPELLING_MEMBER)
4542 for (s = p->u.s; (*d = *s++); d++)
4549 /* Issue an error message for a bad initializer component.
4550 MSGID identifies the message.
4551 The component name is taken from the spelling stack. */
4559 error ("%s", msgid);
4560 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4562 error ("(near initialization for `%s')", ofwhat);
4565 /* Issue a pedantic warning for a bad initializer component.
4566 MSGID identifies the message.
4567 The component name is taken from the spelling stack. */
4570 pedwarn_init (msgid)
4575 pedwarn ("%s", msgid);
4576 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4578 pedwarn ("(near initialization for `%s')", ofwhat);
4581 /* Issue a warning for a bad initializer component.
4582 MSGID identifies the message.
4583 The component name is taken from the spelling stack. */
4586 warning_init (msgid)
4591 warning ("%s", msgid);
4592 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4594 warning ("(near initialization for `%s')", ofwhat);
4597 /* Digest the parser output INIT as an initializer for type TYPE.
4598 Return a C expression of type TYPE to represent the initial value.
4600 The arguments REQUIRE_CONSTANT and CONSTRUCTOR_CONSTANT request errors
4601 if non-constant initializers or elements are seen. CONSTRUCTOR_CONSTANT
4602 applies only to elements of constructors. */
4605 digest_init (type, init, require_constant, constructor_constant)
4607 int require_constant, constructor_constant;
4609 enum tree_code code = TREE_CODE (type);
4610 tree inside_init = init;
4612 if (type == error_mark_node
4613 || init == error_mark_node
4614 || TREE_TYPE (init) == error_mark_node)
4615 return error_mark_node;
4617 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4618 /* Do not use STRIP_NOPS here. We do not want an enumerator
4619 whose value is 0 to count as a null pointer constant. */
4620 if (TREE_CODE (init) == NON_LVALUE_EXPR)
4621 inside_init = TREE_OPERAND (init, 0);
4623 /* Initialization of an array of chars from a string constant
4624 optionally enclosed in braces. */
4626 if (code == ARRAY_TYPE)
4628 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4629 if ((typ1 == char_type_node
4630 || typ1 == signed_char_type_node
4631 || typ1 == unsigned_char_type_node
4632 || typ1 == unsigned_wchar_type_node
4633 || typ1 == signed_wchar_type_node)
4634 && ((inside_init && TREE_CODE (inside_init) == STRING_CST)))
4636 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4637 TYPE_MAIN_VARIANT (type)))
4640 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4642 && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node))
4644 error_init ("char-array initialized from wide string");
4645 return error_mark_node;
4647 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4649 && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node))
4651 error_init ("int-array initialized from non-wide string");
4652 return error_mark_node;
4655 TREE_TYPE (inside_init) = type;
4656 if (TYPE_DOMAIN (type) != 0
4657 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4658 /* Subtract 1 (or sizeof (wchar_t))
4659 because it's ok to ignore the terminating null char
4660 that is counted in the length of the constant. */
4661 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4662 TREE_STRING_LENGTH (inside_init)
4663 - ((TYPE_PRECISION (typ1)
4664 != TYPE_PRECISION (char_type_node))
4665 ? (TYPE_PRECISION (wchar_type_node)
4668 pedwarn_init ("initializer-string for array of chars is too long");
4674 /* Any type can be initialized
4675 from an expression of the same type, optionally with braces. */
4677 if (inside_init && TREE_TYPE (inside_init) != 0
4678 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4679 TYPE_MAIN_VARIANT (type))
4680 || (code == ARRAY_TYPE
4681 && comptypes (TREE_TYPE (inside_init), type))
4682 || (code == POINTER_TYPE
4683 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4684 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE)
4685 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4686 TREE_TYPE (type)))))
4688 if (code == POINTER_TYPE
4689 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4690 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE))
4691 inside_init = default_conversion (inside_init);
4692 else if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4693 && TREE_CODE (inside_init) != CONSTRUCTOR)
4695 error_init ("array initialized from non-constant array expression");
4696 return error_mark_node;
4699 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4700 inside_init = decl_constant_value (inside_init);
4702 /* Compound expressions can only occur here if -pedantic or
4703 -pedantic-errors is specified. In the later case, we always want
4704 an error. In the former case, we simply want a warning. */
4705 if (require_constant && pedantic
4706 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4709 = valid_compound_expr_initializer (inside_init,
4710 TREE_TYPE (inside_init));
4711 if (inside_init == error_mark_node)
4712 error_init ("initializer element is not constant");
4714 pedwarn_init ("initializer element is not constant");
4715 if (flag_pedantic_errors)
4716 inside_init = error_mark_node;
4718 else if (require_constant && ! TREE_CONSTANT (inside_init))
4720 error_init ("initializer element is not constant");
4721 inside_init = error_mark_node;
4723 else if (require_constant
4724 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4726 error_init ("initializer element is not computable at load time");
4727 inside_init = error_mark_node;
4733 /* Handle scalar types, including conversions. */
4735 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4736 || code == ENUMERAL_TYPE || code == COMPLEX_TYPE)
4738 /* Note that convert_for_assignment calls default_conversion
4739 for arrays and functions. We must not call it in the
4740 case where inside_init is a null pointer constant. */
4742 = convert_for_assignment (type, init, _("initialization"),
4743 NULL_TREE, NULL_TREE, 0);
4745 if (require_constant && ! TREE_CONSTANT (inside_init))
4747 error_init ("initializer element is not constant");
4748 inside_init = error_mark_node;
4750 else if (require_constant
4751 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4753 error_init ("initializer element is not computable at load time");
4754 inside_init = error_mark_node;
4760 /* Come here only for records and arrays. */
4762 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4764 error_init ("variable-sized object may not be initialized");
4765 return error_mark_node;
4768 /* Traditionally, you can write struct foo x = 0;
4769 and it initializes the first element of x to 0. */
4770 if (flag_traditional)
4772 tree top = 0, prev = 0, otype = type;
4773 while (TREE_CODE (type) == RECORD_TYPE
4774 || TREE_CODE (type) == ARRAY_TYPE
4775 || TREE_CODE (type) == QUAL_UNION_TYPE
4776 || TREE_CODE (type) == UNION_TYPE)
4778 tree temp = build (CONSTRUCTOR, type, NULL_TREE, NULL_TREE);
4782 TREE_OPERAND (prev, 1) = build_tree_list (NULL_TREE, temp);
4784 if (TREE_CODE (type) == ARRAY_TYPE)
4785 type = TREE_TYPE (type);
4786 else if (TYPE_FIELDS (type))
4787 type = TREE_TYPE (TYPE_FIELDS (type));
4790 error_init ("invalid initializer");
4791 return error_mark_node;
4797 TREE_OPERAND (prev, 1)
4798 = build_tree_list (NULL_TREE,
4799 digest_init (type, init, require_constant,
4800 constructor_constant));
4804 return error_mark_node;
4806 error_init ("invalid initializer");
4807 return error_mark_node;
4810 /* Handle initializers that use braces. */
4812 /* Type of object we are accumulating a constructor for.
4813 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4814 static tree constructor_type;
4816 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4818 static tree constructor_fields;
4820 /* For an ARRAY_TYPE, this is the specified index
4821 at which to store the next element we get. */
4822 static tree constructor_index;
4824 /* For an ARRAY_TYPE, this is the end index of the range
4825 to initialize with the next element, or NULL in the ordinary case
4826 where the element is used just once. */
4827 static tree constructor_range_end;
4829 /* For an ARRAY_TYPE, this is the maximum index. */
4830 static tree constructor_max_index;
4832 /* For a RECORD_TYPE, this is the first field not yet written out. */
4833 static tree constructor_unfilled_fields;
4835 /* For an ARRAY_TYPE, this is the index of the first element
4836 not yet written out. */
4837 static tree constructor_unfilled_index;
4839 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4840 This is so we can generate gaps between fields, when appropriate. */
4841 static tree constructor_bit_index;
4843 /* If we are saving up the elements rather than allocating them,
4844 this is the list of elements so far (in reverse order,
4845 most recent first). */
4846 static tree constructor_elements;
4848 /* 1 if so far this constructor's elements are all compile-time constants. */
4849 static int constructor_constant;
4851 /* 1 if so far this constructor's elements are all valid address constants. */
4852 static int constructor_simple;
4854 /* 1 if this constructor is erroneous so far. */
4855 static int constructor_erroneous;
4857 /* 1 if have called defer_addressed_constants. */
4858 static int constructor_subconstants_deferred;
4860 /* Structure for managing pending initializer elements, organized as an
4865 struct init_node *left, *right;
4866 struct init_node *parent;
4872 /* Tree of pending elements at this constructor level.
4873 These are elements encountered out of order
4874 which belong at places we haven't reached yet in actually
4876 Will never hold tree nodes across GC runs. */
4877 static struct init_node *constructor_pending_elts;
4879 /* The SPELLING_DEPTH of this constructor. */
4880 static int constructor_depth;
4882 /* 0 if implicitly pushing constructor levels is allowed. */
4883 int constructor_no_implicit = 0; /* 0 for C; 1 for some other languages. */
4885 static int require_constant_value;
4886 static int require_constant_elements;
4888 /* 1 if it is ok to output this constructor as we read it.
4889 0 means must accumulate a CONSTRUCTOR expression. */
4890 static int constructor_incremental;
4892 /* DECL node for which an initializer is being read.
4893 0 means we are reading a constructor expression
4894 such as (struct foo) {...}. */
4895 static tree constructor_decl;
4897 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4898 static char *constructor_asmspec;
4900 /* Nonzero if this is an initializer for a top-level decl. */
4901 static int constructor_top_level;
4904 /* This stack has a level for each implicit or explicit level of
4905 structuring in the initializer, including the outermost one. It
4906 saves the values of most of the variables above. */
4908 struct constructor_stack
4910 struct constructor_stack *next;
4916 tree unfilled_index;
4917 tree unfilled_fields;
4921 struct init_node *pending_elts;
4923 /* If nonzero, this value should replace the entire
4924 constructor at this level. */
4925 tree replacement_value;
4934 struct constructor_stack *constructor_stack;
4936 /* This stack records separate initializers that are nested.
4937 Nested initializers can't happen in ANSI C, but GNU C allows them
4938 in cases like { ... (struct foo) { ... } ... }. */
4940 struct initializer_stack
4942 struct initializer_stack *next;
4945 struct constructor_stack *constructor_stack;
4947 struct spelling *spelling;
4948 struct spelling *spelling_base;
4952 char require_constant_value;
4953 char require_constant_elements;
4957 struct initializer_stack *initializer_stack;
4959 /* Prepare to parse and output the initializer for variable DECL. */
4962 start_init (decl, asmspec_tree, top_level)
4968 struct initializer_stack *p
4969 = (struct initializer_stack *) xmalloc (sizeof (struct initializer_stack));
4973 asmspec = TREE_STRING_POINTER (asmspec_tree);
4975 p->decl = constructor_decl;
4976 p->asmspec = constructor_asmspec;
4977 p->incremental = constructor_incremental;
4978 p->require_constant_value = require_constant_value;
4979 p->require_constant_elements = require_constant_elements;
4980 p->constructor_stack = constructor_stack;
4981 p->elements = constructor_elements;
4982 p->spelling = spelling;
4983 p->spelling_base = spelling_base;
4984 p->spelling_size = spelling_size;
4985 p->deferred = constructor_subconstants_deferred;
4986 p->top_level = constructor_top_level;
4987 p->next = initializer_stack;
4988 initializer_stack = p;
4990 constructor_decl = decl;
4991 constructor_incremental = top_level;
4992 constructor_asmspec = asmspec;
4993 constructor_subconstants_deferred = 0;
4994 constructor_top_level = top_level;
4998 require_constant_value = TREE_STATIC (decl);
4999 require_constant_elements
5000 = ((TREE_STATIC (decl) || pedantic)
5001 /* For a scalar, you can always use any value to initialize,
5002 even within braces. */
5003 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
5004 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
5005 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
5006 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
5007 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
5008 constructor_incremental |= TREE_STATIC (decl);
5012 require_constant_value = 0;
5013 require_constant_elements = 0;
5014 locus = "(anonymous)";
5017 constructor_stack = 0;
5019 missing_braces_mentioned = 0;
5023 RESTORE_SPELLING_DEPTH (0);
5026 push_string (locus);
5032 struct initializer_stack *p = initializer_stack;
5034 /* Output subconstants (string constants, usually)
5035 that were referenced within this initializer and saved up.
5036 Must do this if and only if we called defer_addressed_constants. */
5037 if (constructor_subconstants_deferred)
5038 output_deferred_addressed_constants ();
5040 /* Free the whole constructor stack of this initializer. */
5041 while (constructor_stack)
5043 struct constructor_stack *q = constructor_stack;
5044 constructor_stack = q->next;
5048 /* Pop back to the data of the outer initializer (if any). */
5049 constructor_decl = p->decl;
5050 constructor_asmspec = p->asmspec;
5051 constructor_incremental = p->incremental;
5052 require_constant_value = p->require_constant_value;
5053 require_constant_elements = p->require_constant_elements;
5054 constructor_stack = p->constructor_stack;
5055 constructor_elements = p->elements;
5056 spelling = p->spelling;
5057 spelling_base = p->spelling_base;
5058 spelling_size = p->spelling_size;
5059 constructor_subconstants_deferred = p->deferred;
5060 constructor_top_level = p->top_level;
5061 initializer_stack = p->next;
5065 /* Call here when we see the initializer is surrounded by braces.
5066 This is instead of a call to push_init_level;
5067 it is matched by a call to pop_init_level.
5069 TYPE is the type to initialize, for a constructor expression.
5070 For an initializer for a decl, TYPE is zero. */
5073 really_start_incremental_init (type)
5076 struct constructor_stack *p
5077 = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5080 type = TREE_TYPE (constructor_decl);
5082 /* Turn off constructor_incremental if type is a struct with bitfields.
5083 Do this before the first push, so that the corrected value
5084 is available in finish_init. */
5085 check_init_type_bitfields (type);
5087 p->type = constructor_type;
5088 p->fields = constructor_fields;
5089 p->index = constructor_index;
5090 p->range_end = constructor_range_end;
5091 p->max_index = constructor_max_index;
5092 p->unfilled_index = constructor_unfilled_index;
5093 p->unfilled_fields = constructor_unfilled_fields;
5094 p->bit_index = constructor_bit_index;
5095 p->elements = constructor_elements;
5096 p->constant = constructor_constant;
5097 p->simple = constructor_simple;
5098 p->erroneous = constructor_erroneous;
5099 p->pending_elts = constructor_pending_elts;
5100 p->depth = constructor_depth;
5101 p->replacement_value = 0;
5103 p->incremental = constructor_incremental;
5106 constructor_stack = p;
5108 constructor_constant = 1;
5109 constructor_simple = 1;
5110 constructor_depth = SPELLING_DEPTH ();
5111 constructor_elements = 0;
5112 constructor_pending_elts = 0;
5113 constructor_type = type;
5115 if (TREE_CODE (constructor_type) == RECORD_TYPE
5116 || TREE_CODE (constructor_type) == UNION_TYPE)
5118 constructor_fields = TYPE_FIELDS (constructor_type);
5119 /* Skip any nameless bit fields at the beginning. */
5120 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5121 && DECL_NAME (constructor_fields) == 0)
5122 constructor_fields = TREE_CHAIN (constructor_fields);
5124 constructor_unfilled_fields = constructor_fields;
5125 constructor_bit_index = bitsize_zero_node;
5127 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5129 constructor_range_end = 0;
5130 if (TYPE_DOMAIN (constructor_type))
5132 constructor_max_index
5133 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5135 = convert (bitsizetype,
5136 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5139 constructor_index = bitsize_zero_node;
5141 constructor_unfilled_index = constructor_index;
5145 /* Handle the case of int x = {5}; */
5146 constructor_fields = constructor_type;
5147 constructor_unfilled_fields = constructor_type;
5150 if (constructor_incremental)
5152 make_decl_rtl (constructor_decl, constructor_asmspec,
5153 constructor_top_level);
5154 assemble_variable (constructor_decl, constructor_top_level, 0, 1);
5156 defer_addressed_constants ();
5157 constructor_subconstants_deferred = 1;
5161 /* Push down into a subobject, for initialization.
5162 If this is for an explicit set of braces, IMPLICIT is 0.
5163 If it is because the next element belongs at a lower level,
5167 push_init_level (implicit)
5170 struct constructor_stack *p;
5172 /* If we've exhausted any levels that didn't have braces,
5174 while (constructor_stack->implicit)
5176 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5177 || TREE_CODE (constructor_type) == UNION_TYPE)
5178 && constructor_fields == 0)
5179 process_init_element (pop_init_level (1));
5180 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5181 && tree_int_cst_lt (constructor_max_index, constructor_index))
5182 process_init_element (pop_init_level (1));
5187 /* Structure elements may require alignment. Do this now if necessary
5188 for the subaggregate, and if it comes next in sequence. Don't do
5189 this for subaggregates that will go on the pending list. */
5190 if (constructor_incremental && constructor_type != 0
5191 && TREE_CODE (constructor_type) == RECORD_TYPE && constructor_fields
5192 && constructor_fields == constructor_unfilled_fields)
5194 /* Advance to offset of this element. */
5195 if (! tree_int_cst_equal (constructor_bit_index,
5196 bit_position (constructor_fields)))
5199 (size_binop (TRUNC_DIV_EXPR,
5200 size_binop (MINUS_EXPR,
5201 bit_position (constructor_fields),
5202 constructor_bit_index),
5206 /* Indicate that we have now filled the structure up to the current
5208 constructor_unfilled_fields = constructor_fields;
5211 p = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5212 p->type = constructor_type;
5213 p->fields = constructor_fields;
5214 p->index = constructor_index;
5215 p->range_end = constructor_range_end;
5216 p->max_index = constructor_max_index;
5217 p->unfilled_index = constructor_unfilled_index;
5218 p->unfilled_fields = constructor_unfilled_fields;
5219 p->bit_index = constructor_bit_index;
5220 p->elements = constructor_elements;
5221 p->constant = constructor_constant;
5222 p->simple = constructor_simple;
5223 p->erroneous = constructor_erroneous;
5224 p->pending_elts = constructor_pending_elts;
5225 p->depth = constructor_depth;
5226 p->replacement_value = 0;
5227 p->implicit = implicit;
5228 p->incremental = constructor_incremental;
5230 p->next = constructor_stack;
5231 constructor_stack = p;
5233 constructor_constant = 1;
5234 constructor_simple = 1;
5235 constructor_depth = SPELLING_DEPTH ();
5236 constructor_elements = 0;
5237 constructor_pending_elts = 0;
5239 /* Don't die if an entire brace-pair level is superfluous
5240 in the containing level. */
5241 if (constructor_type == 0)
5243 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5244 || TREE_CODE (constructor_type) == UNION_TYPE)
5246 /* Don't die if there are extra init elts at the end. */
5247 if (constructor_fields == 0)
5248 constructor_type = 0;
5251 constructor_type = TREE_TYPE (constructor_fields);
5252 push_member_name (constructor_fields);
5253 constructor_depth++;
5254 if (constructor_fields != constructor_unfilled_fields)
5255 constructor_incremental = 0;
5258 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5260 constructor_type = TREE_TYPE (constructor_type);
5261 push_array_bounds (tree_low_cst (constructor_index, 0));
5262 constructor_depth++;
5263 if (! tree_int_cst_equal (constructor_index, constructor_unfilled_index)
5264 || constructor_range_end != 0)
5265 constructor_incremental = 0;
5268 if (constructor_type == 0)
5270 error_init ("extra brace group at end of initializer");
5271 constructor_fields = 0;
5272 constructor_unfilled_fields = 0;
5276 /* Turn off constructor_incremental if type is a struct with bitfields. */
5277 check_init_type_bitfields (constructor_type);
5279 if (implicit && warn_missing_braces && !missing_braces_mentioned)
5281 missing_braces_mentioned = 1;
5282 warning_init ("missing braces around initializer");
5285 if (TREE_CODE (constructor_type) == RECORD_TYPE
5286 || TREE_CODE (constructor_type) == UNION_TYPE)
5288 constructor_fields = TYPE_FIELDS (constructor_type);
5289 /* Skip any nameless bit fields at the beginning. */
5290 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5291 && DECL_NAME (constructor_fields) == 0)
5292 constructor_fields = TREE_CHAIN (constructor_fields);
5294 constructor_unfilled_fields = constructor_fields;
5295 constructor_bit_index = bitsize_zero_node;
5297 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5299 constructor_range_end = 0;
5300 if (TYPE_DOMAIN (constructor_type))
5302 constructor_max_index
5303 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5305 = convert (bitsizetype,
5307 (TYPE_DOMAIN (constructor_type)));
5310 constructor_index = bitsize_zero_node;
5312 constructor_unfilled_index = constructor_index;
5316 warning_init ("braces around scalar initializer");
5317 constructor_fields = constructor_type;
5318 constructor_unfilled_fields = constructor_type;
5322 /* Don't read a struct incrementally if it has any bitfields,
5323 because the incremental reading code doesn't know how to
5324 handle bitfields yet. */
5327 check_init_type_bitfields (type)
5330 if (TREE_CODE (type) == RECORD_TYPE)
5333 for (tail = TYPE_FIELDS (type); tail;
5334 tail = TREE_CHAIN (tail))
5336 if (DECL_C_BIT_FIELD (tail))
5338 constructor_incremental = 0;
5342 check_init_type_bitfields (TREE_TYPE (tail));
5346 else if (TREE_CODE (type) == UNION_TYPE)
5348 tree tail = TYPE_FIELDS (type);
5349 if (tail && DECL_C_BIT_FIELD (tail))
5350 /* We also use the nonincremental algorithm for initiliazation
5351 of unions whose first member is a bitfield, becuase the
5352 incremental algorithm has no code for dealing with
5354 constructor_incremental = 0;
5357 else if (TREE_CODE (type) == ARRAY_TYPE)
5358 check_init_type_bitfields (TREE_TYPE (type));
5361 /* At the end of an implicit or explicit brace level,
5362 finish up that level of constructor.
5363 If we were outputting the elements as they are read, return 0
5364 from inner levels (process_init_element ignores that),
5365 but return error_mark_node from the outermost level
5366 (that's what we want to put in DECL_INITIAL).
5367 Otherwise, return a CONSTRUCTOR expression. */
5370 pop_init_level (implicit)
5373 struct constructor_stack *p;
5374 HOST_WIDE_INT size = 0;
5375 tree constructor = 0;
5379 /* When we come to an explicit close brace,
5380 pop any inner levels that didn't have explicit braces. */
5381 while (constructor_stack->implicit)
5382 process_init_element (pop_init_level (1));
5385 p = constructor_stack;
5387 if (constructor_type != 0)
5388 size = int_size_in_bytes (constructor_type);
5390 /* Warn when some struct elements are implicitly initialized to zero. */
5393 && TREE_CODE (constructor_type) == RECORD_TYPE
5394 && constructor_unfilled_fields)
5396 push_member_name (constructor_unfilled_fields);
5397 warning_init ("missing initializer");
5398 RESTORE_SPELLING_DEPTH (constructor_depth);
5401 /* Now output all pending elements. */
5402 output_pending_init_elements (1);
5404 #if 0 /* c-parse.in warns about {}. */
5405 /* In ANSI, each brace level must have at least one element. */
5406 if (! implicit && pedantic
5407 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5408 ? integer_zerop (constructor_unfilled_index)
5409 : constructor_unfilled_fields == TYPE_FIELDS (constructor_type)))
5410 pedwarn_init ("empty braces in initializer");
5413 /* Pad out the end of the structure. */
5415 if (p->replacement_value)
5417 /* If this closes a superfluous brace pair,
5418 just pass out the element between them. */
5419 constructor = p->replacement_value;
5420 /* If this is the top level thing within the initializer,
5421 and it's for a variable, then since we already called
5422 assemble_variable, we must output the value now. */
5423 if (p->next == 0 && constructor_decl != 0
5424 && constructor_incremental)
5426 constructor = digest_init (constructor_type, constructor,
5427 require_constant_value,
5428 require_constant_elements);
5430 /* If initializing an array of unknown size,
5431 determine the size now. */
5432 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5433 && TYPE_DOMAIN (constructor_type) == 0)
5435 /* We shouldn't have an incomplete array type within
5437 if (constructor_stack->next)
5440 if (complete_array_type (constructor_type, constructor, 0))
5443 size = int_size_in_bytes (constructor_type);
5446 output_constant (constructor, size);
5449 else if (constructor_type == 0)
5451 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5452 && TREE_CODE (constructor_type) != UNION_TYPE
5453 && TREE_CODE (constructor_type) != ARRAY_TYPE
5454 && ! constructor_incremental)
5456 /* A nonincremental scalar initializer--just return
5457 the element, after verifying there is just one. */
5458 if (constructor_elements == 0)
5460 error_init ("empty scalar initializer");
5461 constructor = error_mark_node;
5463 else if (TREE_CHAIN (constructor_elements) != 0)
5465 error_init ("extra elements in scalar initializer");
5466 constructor = TREE_VALUE (constructor_elements);
5469 constructor = TREE_VALUE (constructor_elements);
5471 else if (! constructor_incremental)
5473 if (constructor_erroneous)
5474 constructor = error_mark_node;
5477 constructor = build (CONSTRUCTOR, constructor_type, NULL_TREE,
5478 nreverse (constructor_elements));
5479 if (constructor_constant)
5480 TREE_CONSTANT (constructor) = 1;
5481 if (constructor_constant && constructor_simple)
5482 TREE_STATIC (constructor) = 1;
5489 if (TREE_CODE (constructor_type) == RECORD_TYPE
5490 || TREE_CODE (constructor_type) == UNION_TYPE)
5491 /* Find the offset of the end of that field. */
5492 filled = size_binop (CEIL_DIV_EXPR, constructor_bit_index,
5495 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5497 /* If initializing an array of unknown size,
5498 determine the size now. */
5499 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5500 && TYPE_DOMAIN (constructor_type) == 0)
5503 = copy_node (size_diffop (constructor_unfilled_index,
5506 TYPE_DOMAIN (constructor_type) = build_index_type (maxindex);
5507 TREE_TYPE (maxindex) = TYPE_DOMAIN (constructor_type);
5509 /* TYPE_MAX_VALUE is always one less than the number of elements
5510 in the array, because we start counting at zero. Therefore,
5511 warn only if the value is less than zero. */
5513 && (tree_int_cst_sgn
5514 (TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5516 error_with_decl (constructor_decl,
5517 "zero or negative array size `%s'");
5519 layout_type (constructor_type);
5520 size = int_size_in_bytes (constructor_type);
5524 = size_binop (MULT_EXPR, constructor_unfilled_index,
5525 convert (bitsizetype,
5527 (TREE_TYPE (constructor_type))));
5533 assemble_zeros (size - tree_low_cst (filled, 1));
5537 constructor_type = p->type;
5538 constructor_fields = p->fields;
5539 constructor_index = p->index;
5540 constructor_range_end = p->range_end;
5541 constructor_max_index = p->max_index;
5542 constructor_unfilled_index = p->unfilled_index;
5543 constructor_unfilled_fields = p->unfilled_fields;
5544 constructor_bit_index = p->bit_index;
5545 constructor_elements = p->elements;
5546 constructor_constant = p->constant;
5547 constructor_simple = p->simple;
5548 constructor_erroneous = p->erroneous;
5549 constructor_pending_elts = p->pending_elts;
5550 constructor_depth = p->depth;
5551 constructor_incremental = p->incremental;
5552 RESTORE_SPELLING_DEPTH (constructor_depth);
5554 constructor_stack = p->next;
5557 if (constructor == 0)
5559 if (constructor_stack == 0)
5560 return error_mark_node;
5566 /* Within an array initializer, specify the next index to be initialized.
5567 FIRST is that index. If LAST is nonzero, then initialize a range
5568 of indices, running from FIRST through LAST. */
5571 set_init_index (first, last)
5574 while ((TREE_CODE (first) == NOP_EXPR
5575 || TREE_CODE (first) == CONVERT_EXPR
5576 || TREE_CODE (first) == NON_LVALUE_EXPR)
5577 && (TYPE_MODE (TREE_TYPE (first))
5578 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0)))))
5579 first = TREE_OPERAND (first, 0);
5582 while ((TREE_CODE (last) == NOP_EXPR
5583 || TREE_CODE (last) == CONVERT_EXPR
5584 || TREE_CODE (last) == NON_LVALUE_EXPR)
5585 && (TYPE_MODE (TREE_TYPE (last))
5586 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0)))))
5587 last = TREE_OPERAND (last, 0);
5589 if (TREE_CODE (first) != INTEGER_CST)
5590 error_init ("nonconstant array index in initializer");
5591 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5592 error_init ("nonconstant array index in initializer");
5593 else if (! constructor_unfilled_index)
5594 error_init ("array index in non-array initializer");
5595 else if (tree_int_cst_lt (first, constructor_unfilled_index))
5596 error_init ("duplicate array index in initializer");
5599 constructor_index = convert (bitsizetype, first);
5601 if (last != 0 && tree_int_cst_lt (last, first))
5602 error_init ("empty index range in initializer");
5606 pedwarn ("ISO C89 forbids specifying element to initialize");
5608 constructor_range_end = last ? convert (bitsizetype, last) : 0;
5613 /* Within a struct initializer, specify the next field to be initialized. */
5616 set_init_label (fieldname)
5622 /* Don't die if an entire brace-pair level is superfluous
5623 in the containing level. */
5624 if (constructor_type == 0)
5627 for (tail = TYPE_FIELDS (constructor_type); tail;
5628 tail = TREE_CHAIN (tail))
5630 if (tail == constructor_unfilled_fields)
5632 if (DECL_NAME (tail) == fieldname)
5637 error ("unknown field `%s' specified in initializer",
5638 IDENTIFIER_POINTER (fieldname));
5640 error ("field `%s' already initialized",
5641 IDENTIFIER_POINTER (fieldname));
5644 constructor_fields = tail;
5646 pedwarn ("ISO C89 forbids specifying structure member to initialize");
5650 /* Add a new initializer to the tree of pending initializers. PURPOSE
5651 indentifies the initializer, either array index or field in a structure.
5652 VALUE is the value of that index or field. */
5655 add_pending_init (purpose, value)
5656 tree purpose, value;
5658 struct init_node *p, **q, *r;
5660 q = &constructor_pending_elts;
5663 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5668 if (tree_int_cst_lt (purpose, p->purpose))
5670 else if (p->purpose != purpose)
5681 if (tree_int_cst_lt (bit_position (purpose),
5682 bit_position (p->purpose)))
5684 else if (p->purpose != purpose)
5691 r = (struct init_node *) ggc_alloc (sizeof (struct init_node));
5692 r->purpose = purpose;
5703 struct init_node *s;
5707 if (p->balance == 0)
5709 else if (p->balance < 0)
5716 p->left->parent = p;
5733 constructor_pending_elts = r;
5738 struct init_node *t = r->right;
5742 r->right->parent = r;
5747 p->left->parent = p;
5750 p->balance = t->balance < 0;
5751 r->balance = -(t->balance > 0);
5766 constructor_pending_elts = t;
5772 /* p->balance == +1; growth of left side balances the node. */
5777 else /* r == p->right */
5779 if (p->balance == 0)
5780 /* Growth propagation from right side. */
5782 else if (p->balance > 0)
5789 p->right->parent = p;
5806 constructor_pending_elts = r;
5808 else /* r->balance == -1 */
5811 struct init_node *t = r->left;
5815 r->left->parent = r;
5820 p->right->parent = p;
5823 r->balance = (t->balance < 0);
5824 p->balance = -(t->balance > 0);
5839 constructor_pending_elts = t;
5845 /* p->balance == -1; growth of right side balances the node. */
5856 /* Return nonzero if FIELD is equal to the index of a pending initializer. */
5859 pending_init_member (field)
5862 struct init_node *p;
5864 p = constructor_pending_elts;
5865 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5869 if (field == p->purpose)
5871 else if (tree_int_cst_lt (field, p->purpose))
5881 if (field == p->purpose)
5883 else if (tree_int_cst_lt (bit_position (field),
5884 bit_position (p->purpose)))
5894 /* "Output" the next constructor element.
5895 At top level, really output it to assembler code now.
5896 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5897 TYPE is the data type that the containing data type wants here.
5898 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5900 PENDING if non-nil means output pending elements that belong
5901 right after this element. (PENDING is normally 1;
5902 it is 0 while outputting pending elements, to avoid recursion.) */
5905 output_init_element (value, type, field, pending)
5906 tree value, type, field;
5911 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5912 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5913 && !(TREE_CODE (value) == STRING_CST
5914 && TREE_CODE (type) == ARRAY_TYPE
5915 && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE)
5916 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5917 TYPE_MAIN_VARIANT (type))))
5918 value = default_conversion (value);
5920 if (value == error_mark_node)
5921 constructor_erroneous = 1;
5922 else if (!TREE_CONSTANT (value))
5923 constructor_constant = 0;
5924 else if (initializer_constant_valid_p (value, TREE_TYPE (value)) == 0
5925 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5926 || TREE_CODE (constructor_type) == UNION_TYPE)
5927 && DECL_C_BIT_FIELD (field)
5928 && TREE_CODE (value) != INTEGER_CST))
5929 constructor_simple = 0;
5931 if (require_constant_value && ! TREE_CONSTANT (value))
5933 error_init ("initializer element is not constant");
5934 value = error_mark_node;
5936 else if (require_constant_elements
5937 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
5939 error_init ("initializer element is not computable at load time");
5940 value = error_mark_node;
5943 /* If this element duplicates one on constructor_pending_elts,
5944 print a message and ignore it. Don't do this when we're
5945 processing elements taken off constructor_pending_elts,
5946 because we'd always get spurious errors. */
5949 if (TREE_CODE (constructor_type) == RECORD_TYPE
5950 || TREE_CODE (constructor_type) == UNION_TYPE
5951 || TREE_CODE (constructor_type) == ARRAY_TYPE)
5953 if (pending_init_member (field))
5955 error_init ("duplicate initializer");
5961 /* If this element doesn't come next in sequence,
5962 put it on constructor_pending_elts. */
5963 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5964 && ! tree_int_cst_equal (field, constructor_unfilled_index))
5967 add_pending_init (field,
5968 digest_init (type, value, require_constant_value,
5969 require_constant_elements));
5971 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5972 && field != constructor_unfilled_fields)
5974 /* We do this for records but not for unions. In a union,
5975 no matter which field is specified, it can be initialized
5976 right away since it starts at the beginning of the union. */
5978 add_pending_init (field,
5979 digest_init (type, value, require_constant_value,
5980 require_constant_elements));
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
6004 && ! tree_int_cst_equal (constructor_bit_index,
6005 bit_position (field)))
6006 /* Advance to offset of this element. */
6009 (size_binop (TRUNC_DIV_EXPR,
6010 size_binop (MINUS_EXPR, bit_position (field),
6011 constructor_bit_index),
6015 output_constant (digest_init (type, value,
6016 require_constant_value,
6017 require_constant_elements),
6018 int_size_in_bytes (type));
6020 /* For a record or union,
6021 keep track of end position of last field. */
6022 if (TREE_CODE (constructor_type) == RECORD_TYPE
6023 || TREE_CODE (constructor_type) == UNION_TYPE)
6024 constructor_bit_index
6025 = size_binop (PLUS_EXPR, bit_position (field),
6030 /* Advance the variable that indicates sequential elements output. */
6031 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6032 constructor_unfilled_index
6033 = size_binop (PLUS_EXPR, constructor_unfilled_index,
6035 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6037 constructor_unfilled_fields
6038 = TREE_CHAIN (constructor_unfilled_fields);
6040 /* Skip any nameless bit fields. */
6041 while (constructor_unfilled_fields != 0
6042 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6043 && DECL_NAME (constructor_unfilled_fields) == 0)
6044 constructor_unfilled_fields =
6045 TREE_CHAIN (constructor_unfilled_fields);
6047 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6048 constructor_unfilled_fields = 0;
6050 /* Now output any pending elements which have become next. */
6052 output_pending_init_elements (0);
6056 /* Output any pending elements which have become next.
6057 As we output elements, constructor_unfilled_{fields,index}
6058 advances, which may cause other elements to become next;
6059 if so, they too are output.
6061 If ALL is 0, we return when there are
6062 no more pending elements to output now.
6064 If ALL is 1, we output space as necessary so that
6065 we can output all the pending elements. */
6068 output_pending_init_elements (all)
6071 struct init_node *elt = constructor_pending_elts;
6076 /* Look thru the whole pending tree.
6077 If we find an element that should be output now,
6078 output it. Otherwise, set NEXT to the element
6079 that comes first among those still pending. */
6084 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6086 if (tree_int_cst_equal (elt->purpose,
6087 constructor_unfilled_index))
6088 output_init_element (elt->value,
6089 TREE_TYPE (constructor_type),
6090 constructor_unfilled_index, 0);
6091 else if (tree_int_cst_lt (constructor_unfilled_index,
6094 /* Advance to the next smaller node. */
6099 /* We have reached the smallest node bigger than the
6100 current unfilled index. Fill the space first. */
6101 next = elt->purpose;
6107 /* Advance to the next bigger node. */
6112 /* We have reached the biggest node in a subtree. Find
6113 the parent of it, which is the next bigger node. */
6114 while (elt->parent && elt->parent->right == elt)
6117 if (elt && tree_int_cst_lt (constructor_unfilled_index,
6120 next = elt->purpose;
6126 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6127 || TREE_CODE (constructor_type) == UNION_TYPE)
6129 /* If the current record is complete we are done. */
6130 if (constructor_unfilled_fields == 0)
6132 if (elt->purpose == constructor_unfilled_fields)
6134 output_init_element (elt->value,
6135 TREE_TYPE (constructor_unfilled_fields),
6136 constructor_unfilled_fields,
6139 else if (tree_int_cst_lt (bit_position (constructor_unfilled_fields),
6140 bit_position (elt->purpose)))
6142 /* Advance to the next smaller node. */
6147 /* We have reached the smallest node bigger than the
6148 current unfilled field. Fill the space first. */
6149 next = elt->purpose;
6155 /* Advance to the next bigger node. */
6160 /* We have reached the biggest node in a subtree. Find
6161 the parent of it, which is the next bigger node. */
6162 while (elt->parent && elt->parent->right == elt)
6167 (bit_position (constructor_unfilled_fields),
6168 bit_position (elt->purpose))))
6170 next = elt->purpose;
6178 /* Ordinarily return, but not if we want to output all
6179 and there are elements left. */
6180 if (! (all && next != 0))
6183 /* Generate space up to the position of NEXT. */
6184 if (constructor_incremental)
6187 tree nextpos_tree = bitsize_zero_node;
6189 if (TREE_CODE (constructor_type) == RECORD_TYPE
6190 || TREE_CODE (constructor_type) == UNION_TYPE)
6194 /* Find the last field written out, if any. */
6195 for (tail = TYPE_FIELDS (constructor_type); tail;
6196 tail = TREE_CHAIN (tail))
6197 if (TREE_CHAIN (tail) == constructor_unfilled_fields)
6201 /* Find the offset of the end of that field. */
6202 filled = size_binop (CEIL_DIV_EXPR,
6203 size_binop (PLUS_EXPR, bit_position (tail),
6207 filled = bitsize_zero_node;
6209 nextpos_tree = convert (bitsizetype, byte_position (next));
6210 constructor_bit_index = bit_position (next);
6211 constructor_unfilled_fields = next;
6213 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6216 = size_binop (MULT_EXPR, constructor_unfilled_index,
6217 convert (bitsizetype,
6219 (TREE_TYPE (constructor_type))));
6221 = size_binop (MULT_EXPR, next,
6222 convert (bitsizetype, TYPE_SIZE_UNIT
6223 (TREE_TYPE (constructor_type))));
6224 constructor_unfilled_index = next;
6230 assemble_zeros (tree_low_cst (size_diffop (nextpos_tree, filled), 1));
6234 /* If it's not incremental, just skip over the gap,
6235 so that after jumping to retry we will output the next
6236 successive element. */
6237 if (TREE_CODE (constructor_type) == RECORD_TYPE
6238 || TREE_CODE (constructor_type) == UNION_TYPE)
6239 constructor_unfilled_fields = next;
6240 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6241 constructor_unfilled_index = next;
6244 /* ELT now points to the node in the pending tree with the next
6245 initializer to output. */
6249 /* Add one non-braced element to the current constructor level.
6250 This adjusts the current position within the constructor's type.
6251 This may also start or terminate implicit levels
6252 to handle a partly-braced initializer.
6254 Once this has found the correct level for the new element,
6255 it calls output_init_element.
6257 Note: if we are incrementally outputting this constructor,
6258 this function may be called with a null argument
6259 representing a sub-constructor that was already incrementally output.
6260 When that happens, we output nothing, but we do the bookkeeping
6261 to skip past that element of the current constructor. */
6264 process_init_element (value)
6267 tree orig_value = value;
6268 int string_flag = value != 0 && TREE_CODE (value) == STRING_CST;
6270 /* Handle superfluous braces around string cst as in
6271 char x[] = {"foo"}; */
6274 && TREE_CODE (constructor_type) == ARRAY_TYPE
6275 && TREE_CODE (TREE_TYPE (constructor_type)) == INTEGER_TYPE
6276 && integer_zerop (constructor_unfilled_index))
6278 if (constructor_stack->replacement_value)
6279 error_init ("excess elements in char array initializer");
6280 constructor_stack->replacement_value = value;
6284 if (constructor_stack->replacement_value != 0)
6286 error_init ("excess elements in struct initializer");
6290 /* Ignore elements of a brace group if it is entirely superfluous
6291 and has already been diagnosed. */
6292 if (constructor_type == 0)
6295 /* If we've exhausted any levels that didn't have braces,
6297 while (constructor_stack->implicit)
6299 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6300 || TREE_CODE (constructor_type) == UNION_TYPE)
6301 && constructor_fields == 0)
6302 process_init_element (pop_init_level (1));
6303 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6304 && (constructor_max_index == 0
6305 || tree_int_cst_lt (constructor_max_index,
6306 constructor_index)))
6307 process_init_element (pop_init_level (1));
6314 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6317 enum tree_code fieldcode;
6319 if (constructor_fields == 0)
6321 pedwarn_init ("excess elements in struct initializer");
6325 fieldtype = TREE_TYPE (constructor_fields);
6326 if (fieldtype != error_mark_node)
6327 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6328 fieldcode = TREE_CODE (fieldtype);
6330 /* Accept a string constant to initialize a subarray. */
6332 && fieldcode == ARRAY_TYPE
6333 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6336 /* Otherwise, if we have come to a subaggregate,
6337 and we don't have an element of its type, push into it. */
6338 else if (value != 0 && !constructor_no_implicit
6339 && value != error_mark_node
6340 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6341 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6342 || fieldcode == UNION_TYPE))
6344 push_init_level (1);
6350 push_member_name (constructor_fields);
6351 output_init_element (value, fieldtype, constructor_fields, 1);
6352 RESTORE_SPELLING_DEPTH (constructor_depth);
6355 /* Do the bookkeeping for an element that was
6356 directly output as a constructor. */
6358 /* For a record, keep track of end position of last field. */
6359 constructor_bit_index
6360 = size_binop (PLUS_EXPR,
6361 bit_position (constructor_fields),
6362 DECL_SIZE (constructor_fields));
6364 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6365 /* Skip any nameless bit fields. */
6366 while (constructor_unfilled_fields != 0
6367 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6368 && DECL_NAME (constructor_unfilled_fields) == 0)
6369 constructor_unfilled_fields =
6370 TREE_CHAIN (constructor_unfilled_fields);
6373 constructor_fields = TREE_CHAIN (constructor_fields);
6374 /* Skip any nameless bit fields at the beginning. */
6375 while (constructor_fields != 0
6376 && DECL_C_BIT_FIELD (constructor_fields)
6377 && DECL_NAME (constructor_fields) == 0)
6378 constructor_fields = TREE_CHAIN (constructor_fields);
6381 if (TREE_CODE (constructor_type) == UNION_TYPE)
6384 enum tree_code fieldcode;
6386 if (constructor_fields == 0)
6388 pedwarn_init ("excess elements in union initializer");
6392 fieldtype = TREE_TYPE (constructor_fields);
6393 if (fieldtype != error_mark_node)
6394 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6395 fieldcode = TREE_CODE (fieldtype);
6397 /* Warn that traditional C rejects initialization of unions.
6398 We skip the warning if the value is zero. This is done
6399 under the assumption that the zero initializer in user
6400 code appears conditioned on e.g. __STDC__ to avoid
6401 "missing initializer" warnings and relies on default
6402 initialization to zero in the traditional C case. */
6403 if (warn_traditional && !integer_zerop (value))
6404 warning ("traditional C rejects initialization of unions");
6406 /* Accept a string constant to initialize a subarray. */
6408 && fieldcode == ARRAY_TYPE
6409 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6412 /* Otherwise, if we have come to a subaggregate,
6413 and we don't have an element of its type, push into it. */
6414 else if (value != 0 && !constructor_no_implicit
6415 && value != error_mark_node
6416 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6417 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6418 || fieldcode == UNION_TYPE))
6420 push_init_level (1);
6426 push_member_name (constructor_fields);
6427 output_init_element (value, fieldtype, constructor_fields, 1);
6428 RESTORE_SPELLING_DEPTH (constructor_depth);
6431 /* Do the bookkeeping for an element that was
6432 directly output as a constructor. */
6434 constructor_bit_index = DECL_SIZE (constructor_fields);
6435 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6438 constructor_fields = 0;
6441 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6443 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6444 enum tree_code eltcode = TREE_CODE (elttype);
6446 /* Accept a string constant to initialize a subarray. */
6448 && eltcode == ARRAY_TYPE
6449 && TREE_CODE (TREE_TYPE (elttype)) == INTEGER_TYPE
6452 /* Otherwise, if we have come to a subaggregate,
6453 and we don't have an element of its type, push into it. */
6454 else if (value != 0 && !constructor_no_implicit
6455 && value != error_mark_node
6456 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != elttype
6457 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6458 || eltcode == UNION_TYPE))
6460 push_init_level (1);
6464 if (constructor_max_index != 0
6465 && tree_int_cst_lt (constructor_max_index, constructor_index))
6467 pedwarn_init ("excess elements in array initializer");
6471 /* In the case of [LO .. HI] = VALUE, only evaluate VALUE once. */
6472 if (constructor_range_end)
6474 if (constructor_max_index != 0
6475 && tree_int_cst_lt (constructor_max_index,
6476 constructor_range_end))
6478 pedwarn_init ("excess elements in array initializer");
6479 constructor_range_end = constructor_max_index;
6482 value = save_expr (value);
6485 /* Now output the actual element.
6486 Ordinarily, output once.
6487 If there is a range, repeat it till we advance past the range. */
6492 push_array_bounds (tree_low_cst (constructor_index, 0));
6493 output_init_element (value, elttype, constructor_index, 1);
6494 RESTORE_SPELLING_DEPTH (constructor_depth);
6498 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6501 /* If we are doing the bookkeeping for an element that was
6502 directly output as a constructor, we must update
6503 constructor_unfilled_index. */
6504 constructor_unfilled_index = constructor_index;
6506 while (! (constructor_range_end == 0
6507 || tree_int_cst_lt (constructor_range_end,
6508 constructor_index)));
6513 /* Handle the sole element allowed in a braced initializer
6514 for a scalar variable. */
6515 if (constructor_fields == 0)
6517 pedwarn_init ("excess elements in scalar initializer");
6522 output_init_element (value, constructor_type, NULL_TREE, 1);
6523 constructor_fields = 0;
6528 /* Expand an ASM statement with operands, handling output operands
6529 that are not variables or INDIRECT_REFS by transforming such
6530 cases into cases that expand_asm_operands can handle.
6532 Arguments are same as for expand_asm_operands. */
6535 c_expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line)
6536 tree string, outputs, inputs, clobbers;
6538 const char *filename;
6541 int noutputs = list_length (outputs);
6543 /* o[I] is the place that output number I should be written. */
6544 register tree *o = (tree *) alloca (noutputs * sizeof (tree));
6547 if (TREE_CODE (string) == ADDR_EXPR)
6548 string = TREE_OPERAND (string, 0);
6549 if (TREE_CODE (string) != STRING_CST)
6551 error ("asm template is not a string constant");
6555 /* Record the contents of OUTPUTS before it is modified. */
6556 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6558 tree output = TREE_VALUE (tail);
6560 /* We can remove conversions that just change the type, not the mode. */
6561 STRIP_NOPS (output);
6564 /* Allow conversions as LHS here. build_modify_expr as called below
6565 will do the right thing with them. */
6566 while (TREE_CODE (output) == NOP_EXPR
6567 || TREE_CODE (output) == CONVERT_EXPR
6568 || TREE_CODE (output) == FLOAT_EXPR
6569 || TREE_CODE (output) == FIX_TRUNC_EXPR
6570 || TREE_CODE (output) == FIX_FLOOR_EXPR
6571 || TREE_CODE (output) == FIX_ROUND_EXPR
6572 || TREE_CODE (output) == FIX_CEIL_EXPR)
6573 output = TREE_OPERAND (output, 0);
6575 lvalue_or_else (o[i], "invalid lvalue in asm statement");
6578 /* Perform default conversions on array and function inputs. */
6579 /* Don't do this for other types--
6580 it would screw up operands expected to be in memory. */
6581 for (i = 0, tail = inputs; tail; tail = TREE_CHAIN (tail), i++)
6582 if (TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == ARRAY_TYPE
6583 || TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == FUNCTION_TYPE)
6584 TREE_VALUE (tail) = default_conversion (TREE_VALUE (tail));
6586 /* Generate the ASM_OPERANDS insn;
6587 store into the TREE_VALUEs of OUTPUTS some trees for
6588 where the values were actually stored. */
6589 expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line);
6591 /* Copy all the intermediate outputs into the specified outputs. */
6592 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6594 if (o[i] != TREE_VALUE (tail))
6596 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
6597 NULL_RTX, VOIDmode, EXPAND_NORMAL);
6600 /* Detect modification of read-only values.
6601 (Otherwise done by build_modify_expr.) */
6604 tree type = TREE_TYPE (o[i]);
6605 if (TREE_READONLY (o[i])
6606 || TYPE_READONLY (type)
6607 || ((TREE_CODE (type) == RECORD_TYPE
6608 || TREE_CODE (type) == UNION_TYPE)
6609 && C_TYPE_FIELDS_READONLY (type)))
6610 readonly_warning (o[i], "modification by `asm'");
6614 /* Those MODIFY_EXPRs could do autoincrements. */
6618 /* Expand a C `return' statement.
6619 RETVAL is the expression for what to return,
6620 or a null pointer for `return;' with no value. */
6623 c_expand_return (retval)
6626 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6628 if (TREE_THIS_VOLATILE (current_function_decl))
6629 warning ("function declared `noreturn' has a `return' statement");
6633 current_function_returns_null = 1;
6634 if ((warn_return_type || flag_isoc99)
6635 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6636 pedwarn_c99 ("`return' with no value, in function returning non-void");
6637 expand_null_return ();
6639 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6641 current_function_returns_null = 1;
6642 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6643 pedwarn ("`return' with a value, in function returning void");
6644 expand_return (retval);
6648 tree t = convert_for_assignment (valtype, retval, _("return"),
6649 NULL_TREE, NULL_TREE, 0);
6650 tree res = DECL_RESULT (current_function_decl);
6653 if (t == error_mark_node)
6656 inner = t = convert (TREE_TYPE (res), t);
6658 /* Strip any conversions, additions, and subtractions, and see if
6659 we are returning the address of a local variable. Warn if so. */
6662 switch (TREE_CODE (inner))
6664 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6666 inner = TREE_OPERAND (inner, 0);
6670 /* If the second operand of the MINUS_EXPR has a pointer
6671 type (or is converted from it), this may be valid, so
6672 don't give a warning. */
6674 tree op1 = TREE_OPERAND (inner, 1);
6676 while (! POINTER_TYPE_P (TREE_TYPE (op1))
6677 && (TREE_CODE (op1) == NOP_EXPR
6678 || TREE_CODE (op1) == NON_LVALUE_EXPR
6679 || TREE_CODE (op1) == CONVERT_EXPR))
6680 op1 = TREE_OPERAND (op1, 0);
6682 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6685 inner = TREE_OPERAND (inner, 0);
6690 inner = TREE_OPERAND (inner, 0);
6692 while (TREE_CODE_CLASS (TREE_CODE (inner)) == 'r')
6693 inner = TREE_OPERAND (inner, 0);
6695 if (TREE_CODE (inner) == VAR_DECL
6696 && ! DECL_EXTERNAL (inner)
6697 && ! TREE_STATIC (inner)
6698 && DECL_CONTEXT (inner) == current_function_decl)
6699 warning ("function returns address of local variable");
6709 t = build (MODIFY_EXPR, TREE_TYPE (res), res, t);
6710 TREE_SIDE_EFFECTS (t) = 1;
6712 current_function_returns_value = 1;
6716 /* Start a C switch statement, testing expression EXP.
6717 Return EXP if it is valid, an error node otherwise. */
6720 c_expand_start_case (exp)
6723 register enum tree_code code;
6726 if (TREE_CODE (exp) == ERROR_MARK)
6729 code = TREE_CODE (TREE_TYPE (exp));
6730 type = TREE_TYPE (exp);
6732 if (code != INTEGER_TYPE && code != ENUMERAL_TYPE && code != ERROR_MARK)
6734 error ("switch quantity not an integer");
6735 exp = error_mark_node;
6740 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6742 if (warn_traditional
6743 && ! in_system_header
6744 && (type == long_integer_type_node
6745 || type == long_unsigned_type_node))
6746 warning ("`long' switch expression not converted to `int' in ISO C");
6748 exp = default_conversion (exp);
6749 type = TREE_TYPE (exp);
6750 index = get_unwidened (exp, NULL_TREE);
6751 /* We can't strip a conversion from a signed type to an unsigned,
6752 because if we did, int_fits_type_p would do the wrong thing
6753 when checking case values for being in range,
6754 and it's too hard to do the right thing. */
6755 if (TREE_UNSIGNED (TREE_TYPE (exp))
6756 == TREE_UNSIGNED (TREE_TYPE (index)))
6760 expand_start_case (1, exp, type, "switch statement");