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 lookup_field PARAMS ((tree, tree, tree *));
58 static tree convert_arguments PARAMS ((tree, tree, tree, tree));
59 static tree pointer_int_sum PARAMS ((enum tree_code, tree, tree));
60 static tree pointer_diff PARAMS ((tree, tree));
61 static tree unary_complex_lvalue PARAMS ((enum tree_code, tree));
62 static void pedantic_lvalue_warning PARAMS ((enum tree_code));
63 static tree internal_build_compound_expr PARAMS ((tree, int));
64 static tree convert_for_assignment PARAMS ((tree, tree, const char *,
66 static void warn_for_assignment PARAMS ((const char *, const char *,
68 static tree valid_compound_expr_initializer PARAMS ((tree, tree));
69 static void push_string PARAMS ((const char *));
70 static void push_member_name PARAMS ((tree));
71 static void push_array_bounds PARAMS ((int));
72 static int spelling_length PARAMS ((void));
73 static char *print_spelling PARAMS ((char *));
74 static void warning_init PARAMS ((const char *));
75 static tree digest_init PARAMS ((tree, tree, int, int));
76 static void check_init_type_bitfields PARAMS ((tree));
77 static void output_init_element PARAMS ((tree, tree, tree, int));
78 static void output_pending_init_elements PARAMS ((int));
79 static void add_pending_init PARAMS ((tree, tree));
80 static int pending_init_member PARAMS ((tree));
82 /* Do `exp = require_complete_type (exp);' to make sure exp
83 does not have an incomplete type. (That includes void types.) */
86 require_complete_type (value)
89 tree type = TREE_TYPE (value);
91 if (TREE_CODE (value) == ERROR_MARK)
92 return error_mark_node;
94 /* First, detect a valid value with a complete type. */
95 if (COMPLETE_TYPE_P (type))
98 incomplete_type_error (value, type);
99 return error_mark_node;
102 /* Print an error message for invalid use of an incomplete type.
103 VALUE is the expression that was used (or 0 if that isn't known)
104 and TYPE is the type that was invalid. */
107 incomplete_type_error (value, type)
111 const char *type_code_string;
113 /* Avoid duplicate error message. */
114 if (TREE_CODE (type) == ERROR_MARK)
117 if (value != 0 && (TREE_CODE (value) == VAR_DECL
118 || TREE_CODE (value) == PARM_DECL))
119 error ("`%s' has an incomplete type",
120 IDENTIFIER_POINTER (DECL_NAME (value)));
124 /* We must print an error message. Be clever about what it says. */
126 switch (TREE_CODE (type))
129 type_code_string = "struct";
133 type_code_string = "union";
137 type_code_string = "enum";
141 error ("invalid use of void expression");
145 if (TYPE_DOMAIN (type))
147 type = TREE_TYPE (type);
150 error ("invalid use of array with unspecified bounds");
157 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
158 error ("invalid use of undefined type `%s %s'",
159 type_code_string, IDENTIFIER_POINTER (TYPE_NAME (type)));
161 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
162 error ("invalid use of incomplete typedef `%s'",
163 IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
167 /* Return a variant of TYPE which has all the type qualifiers of LIKE
168 as well as those of TYPE. */
171 qualify_type (type, like)
174 return c_build_qualified_type (type,
175 TYPE_QUALS (type) | TYPE_QUALS (like));
178 /* Return the common type of two types.
179 We assume that comptypes has already been done and returned 1;
180 if that isn't so, this may crash. In particular, we assume that qualifiers
183 This is the type for the result of most arithmetic operations
184 if the operands have the given two types. */
190 register enum tree_code code1;
191 register enum tree_code code2;
194 /* Save time if the two types are the same. */
196 if (t1 == t2) return t1;
198 /* If one type is nonsense, use the other. */
199 if (t1 == error_mark_node)
201 if (t2 == error_mark_node)
204 /* Merge the attributes. */
205 attributes = merge_machine_type_attributes (t1, t2);
207 /* Treat an enum type as the unsigned integer type of the same width. */
209 if (TREE_CODE (t1) == ENUMERAL_TYPE)
210 t1 = type_for_size (TYPE_PRECISION (t1), 1);
211 if (TREE_CODE (t2) == ENUMERAL_TYPE)
212 t2 = type_for_size (TYPE_PRECISION (t2), 1);
214 code1 = TREE_CODE (t1);
215 code2 = TREE_CODE (t2);
217 /* If one type is complex, form the common type of the non-complex
218 components, then make that complex. Use T1 or T2 if it is the
220 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
222 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
223 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
224 tree subtype = common_type (subtype1, subtype2);
226 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
227 return build_type_attribute_variant (t1, attributes);
228 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
229 return build_type_attribute_variant (t2, attributes);
231 return build_type_attribute_variant (build_complex_type (subtype),
239 /* If only one is real, use it as the result. */
241 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
242 return build_type_attribute_variant (t1, attributes);
244 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
245 return build_type_attribute_variant (t2, attributes);
247 /* Both real or both integers; use the one with greater precision. */
249 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
250 return build_type_attribute_variant (t1, attributes);
251 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
252 return build_type_attribute_variant (t2, attributes);
254 /* Same precision. Prefer longs to ints even when same size. */
256 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
257 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
258 return build_type_attribute_variant (long_unsigned_type_node,
261 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
262 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
264 /* But preserve unsignedness from the other type,
265 since long cannot hold all the values of an unsigned int. */
266 if (TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
267 t1 = long_unsigned_type_node;
269 t1 = long_integer_type_node;
270 return build_type_attribute_variant (t1, attributes);
273 /* Likewise, prefer long double to double even if same size. */
274 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
275 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
276 return build_type_attribute_variant (long_double_type_node,
279 /* Otherwise prefer the unsigned one. */
281 if (TREE_UNSIGNED (t1))
282 return build_type_attribute_variant (t1, attributes);
284 return build_type_attribute_variant (t2, attributes);
287 /* For two pointers, do this recursively on the target type,
288 and combine the qualifiers of the two types' targets. */
289 /* This code was turned off; I don't know why.
290 But ANSI C specifies doing this with the qualifiers.
291 So I turned it on again. */
293 tree pointed_to_1 = TREE_TYPE (t1);
294 tree pointed_to_2 = TREE_TYPE (t2);
295 tree target = common_type (TYPE_MAIN_VARIANT (pointed_to_1),
296 TYPE_MAIN_VARIANT (pointed_to_2));
297 t1 = build_pointer_type (c_build_qualified_type
299 TYPE_QUALS (pointed_to_1) |
300 TYPE_QUALS (pointed_to_2)));
301 return build_type_attribute_variant (t1, attributes);
304 t1 = build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2)));
305 return build_type_attribute_variant (t1, attributes);
310 tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
311 /* Save space: see if the result is identical to one of the args. */
312 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
313 return build_type_attribute_variant (t1, attributes);
314 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
315 return build_type_attribute_variant (t2, attributes);
316 /* Merge the element types, and have a size if either arg has one. */
317 t1 = build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
318 return build_type_attribute_variant (t1, attributes);
322 /* Function types: prefer the one that specified arg types.
323 If both do, merge the arg types. Also merge the return types. */
325 tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
326 tree p1 = TYPE_ARG_TYPES (t1);
327 tree p2 = TYPE_ARG_TYPES (t2);
332 /* Save space: see if the result is identical to one of the args. */
333 if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2))
334 return build_type_attribute_variant (t1, attributes);
335 if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1))
336 return build_type_attribute_variant (t2, attributes);
338 /* Simple way if one arg fails to specify argument types. */
339 if (TYPE_ARG_TYPES (t1) == 0)
341 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
342 return build_type_attribute_variant (t1, attributes);
344 if (TYPE_ARG_TYPES (t2) == 0)
346 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
347 return build_type_attribute_variant (t1, attributes);
350 /* If both args specify argument types, we must merge the two
351 lists, argument by argument. */
353 len = list_length (p1);
356 for (i = 0; i < len; i++)
357 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
362 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
364 /* A null type means arg type is not specified.
365 Take whatever the other function type has. */
366 if (TREE_VALUE (p1) == 0)
368 TREE_VALUE (n) = TREE_VALUE (p2);
371 if (TREE_VALUE (p2) == 0)
373 TREE_VALUE (n) = TREE_VALUE (p1);
377 /* Given wait (union {union wait *u; int *i} *)
378 and wait (union wait *),
379 prefer union wait * as type of parm. */
380 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
381 && TREE_VALUE (p1) != TREE_VALUE (p2))
384 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
385 memb; memb = TREE_CHAIN (memb))
386 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2)))
388 TREE_VALUE (n) = TREE_VALUE (p2);
390 pedwarn ("function types not truly compatible in ISO C");
394 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
395 && TREE_VALUE (p2) != TREE_VALUE (p1))
398 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
399 memb; memb = TREE_CHAIN (memb))
400 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1)))
402 TREE_VALUE (n) = TREE_VALUE (p1);
404 pedwarn ("function types not truly compatible in ISO C");
408 TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2));
412 t1 = build_function_type (valtype, newargs);
413 /* ... falls through ... */
417 return build_type_attribute_variant (t1, attributes);
422 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
423 or various other operations. Return 2 if they are compatible
424 but a warning may be needed if you use them together. */
427 comptypes (type1, type2)
430 register tree t1 = type1;
431 register tree t2 = type2;
434 /* Suppress errors caused by previously reported errors. */
436 if (t1 == t2 || !t1 || !t2
437 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
440 /* If either type is the internal version of sizetype, return the
442 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
443 && TYPE_DOMAIN (t1) != 0)
444 t1 = TYPE_DOMAIN (t1);
446 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
447 && TYPE_DOMAIN (t2) != 0)
448 t2 = TYPE_DOMAIN (t2);
450 /* Treat an enum type as the integer type of the same width and
453 if (TREE_CODE (t1) == ENUMERAL_TYPE)
454 t1 = type_for_size (TYPE_PRECISION (t1), TREE_UNSIGNED (t1));
455 if (TREE_CODE (t2) == ENUMERAL_TYPE)
456 t2 = type_for_size (TYPE_PRECISION (t2), TREE_UNSIGNED (t2));
461 /* Different classes of types can't be compatible. */
463 if (TREE_CODE (t1) != TREE_CODE (t2)) return 0;
465 /* Qualifiers must match. */
467 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
470 /* Allow for two different type nodes which have essentially the same
471 definition. Note that we already checked for equality of the type
472 qualifiers (just above). */
474 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
477 #ifndef COMP_TYPE_ATTRIBUTES
478 #define COMP_TYPE_ATTRIBUTES(t1,t2) 1
481 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
482 if (! (attrval = COMP_TYPE_ATTRIBUTES (t1, t2)))
485 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
488 switch (TREE_CODE (t1))
491 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
492 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
496 val = function_types_compatible_p (t1, t2);
501 tree d1 = TYPE_DOMAIN (t1);
502 tree d2 = TYPE_DOMAIN (t2);
505 /* Target types must match incl. qualifiers. */
506 if (TREE_TYPE (t1) != TREE_TYPE (t2)
507 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
510 /* Sizes must match unless one is missing or variable. */
511 if (d1 == 0 || d2 == 0 || d1 == d2
512 || TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
513 || TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
514 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST
515 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)
518 if (! tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
519 || ! tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
526 if (maybe_objc_comptypes (t1, t2, 0) == 1)
533 return attrval == 2 && val == 1 ? 2 : val;
536 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
537 ignoring their qualifiers. */
540 comp_target_types (ttl, ttr)
545 /* Give maybe_objc_comptypes a crack at letting these types through. */
546 if ((val = maybe_objc_comptypes (ttl, ttr, 1)) >= 0)
549 val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)),
550 TYPE_MAIN_VARIANT (TREE_TYPE (ttr)));
552 if (val == 2 && pedantic)
553 pedwarn ("types are not quite compatible");
557 /* Subroutines of `comptypes'. */
559 /* Return 1 if two function types F1 and F2 are compatible.
560 If either type specifies no argument types,
561 the other must specify a fixed number of self-promoting arg types.
562 Otherwise, if one type specifies only the number of arguments,
563 the other must specify that number of self-promoting arg types.
564 Otherwise, the argument types must match. */
567 function_types_compatible_p (f1, f2)
571 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
575 if (!(TREE_TYPE (f1) == TREE_TYPE (f2)
576 || (val = comptypes (TREE_TYPE (f1), TREE_TYPE (f2)))))
579 args1 = TYPE_ARG_TYPES (f1);
580 args2 = TYPE_ARG_TYPES (f2);
582 /* An unspecified parmlist matches any specified parmlist
583 whose argument types don't need default promotions. */
587 if (!self_promoting_args_p (args2))
589 /* If one of these types comes from a non-prototype fn definition,
590 compare that with the other type's arglist.
591 If they don't match, ask for a warning (but no error). */
592 if (TYPE_ACTUAL_ARG_TYPES (f1)
593 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
599 if (!self_promoting_args_p (args1))
601 if (TYPE_ACTUAL_ARG_TYPES (f2)
602 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
607 /* Both types have argument lists: compare them and propagate results. */
608 val1 = type_lists_compatible_p (args1, args2);
609 return val1 != 1 ? val1 : val;
612 /* Check two lists of types for compatibility,
613 returning 0 for incompatible, 1 for compatible,
614 or 2 for compatible with warning. */
617 type_lists_compatible_p (args1, args2)
620 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
626 if (args1 == 0 && args2 == 0)
628 /* If one list is shorter than the other,
629 they fail to match. */
630 if (args1 == 0 || args2 == 0)
632 /* A null pointer instead of a type
633 means there is supposed to be an argument
634 but nothing is specified about what type it has.
635 So match anything that self-promotes. */
636 if (TREE_VALUE (args1) == 0)
638 if (simple_type_promotes_to (TREE_VALUE (args2)) != NULL_TREE)
641 else if (TREE_VALUE (args2) == 0)
643 if (simple_type_promotes_to (TREE_VALUE (args1)) != NULL_TREE)
646 else if (! (newval = comptypes (TREE_VALUE (args1), TREE_VALUE (args2))))
648 /* Allow wait (union {union wait *u; int *i} *)
649 and wait (union wait *) to be compatible. */
650 if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE
651 && (TYPE_NAME (TREE_VALUE (args1)) == 0
652 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args1)))
653 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST
654 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)),
655 TYPE_SIZE (TREE_VALUE (args2))))
658 for (memb = TYPE_FIELDS (TREE_VALUE (args1));
659 memb; memb = TREE_CHAIN (memb))
660 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2)))
665 else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE
666 && (TYPE_NAME (TREE_VALUE (args2)) == 0
667 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args2)))
668 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST
669 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)),
670 TYPE_SIZE (TREE_VALUE (args1))))
673 for (memb = TYPE_FIELDS (TREE_VALUE (args2));
674 memb; memb = TREE_CHAIN (memb))
675 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1)))
684 /* comptypes said ok, but record if it said to warn. */
688 args1 = TREE_CHAIN (args1);
689 args2 = TREE_CHAIN (args2);
693 /* Compute the value of the `sizeof' operator. */
699 enum tree_code code = TREE_CODE (type);
701 if (code == FUNCTION_TYPE)
703 if (pedantic || warn_pointer_arith)
704 pedwarn ("sizeof applied to a function type");
705 return size_one_node;
707 if (code == VOID_TYPE)
709 if (pedantic || warn_pointer_arith)
710 pedwarn ("sizeof applied to a void type");
711 return size_one_node;
714 if (code == ERROR_MARK)
715 return size_one_node;
717 if (!COMPLETE_TYPE_P (type))
719 error ("sizeof applied to an incomplete type");
720 return size_zero_node;
723 /* Convert in case a char is more than one unit. */
724 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
725 size_int (TYPE_PRECISION (char_type_node)
730 c_sizeof_nowarn (type)
733 enum tree_code code = TREE_CODE (type);
735 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
736 return size_one_node;
738 if (!COMPLETE_TYPE_P (type))
739 return size_zero_node;
741 /* Convert in case a char is more than one unit. */
742 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
743 size_int (TYPE_PRECISION (char_type_node)
747 /* Compute the size to increment a pointer by. */
750 c_size_in_bytes (type)
753 enum tree_code code = TREE_CODE (type);
755 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
756 return size_one_node;
758 if (!COMPLETE_OR_VOID_TYPE_P (type))
760 error ("arithmetic on pointer to an incomplete type");
761 return size_one_node;
764 /* Convert in case a char is more than one unit. */
765 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
766 size_int (TYPE_PRECISION (char_type_node)
770 /* Implement the __alignof keyword: Return the minimum required
771 alignment of TYPE, measured in bytes. */
777 enum tree_code code = TREE_CODE (type);
779 if (code == FUNCTION_TYPE)
780 return size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
782 if (code == VOID_TYPE || code == ERROR_MARK)
783 return size_one_node;
785 if (!COMPLETE_TYPE_P (type))
787 error ("__alignof__ applied to an incomplete type");
788 return size_zero_node;
791 return size_int (TYPE_ALIGN (type) / BITS_PER_UNIT);
794 /* Implement the __alignof keyword: Return the minimum required
795 alignment of EXPR, measured in bytes. For VAR_DECL's and
796 FIELD_DECL's return DECL_ALIGN (which can be set from an
797 "aligned" __attribute__ specification). */
800 c_alignof_expr (expr)
803 if (TREE_CODE (expr) == VAR_DECL)
804 return size_int (DECL_ALIGN (expr) / BITS_PER_UNIT);
806 if (TREE_CODE (expr) == COMPONENT_REF
807 && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1)))
809 error ("`__alignof' applied to a bit-field");
810 return size_one_node;
812 else if (TREE_CODE (expr) == COMPONENT_REF
813 && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
814 return size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT);
816 if (TREE_CODE (expr) == INDIRECT_REF)
818 tree t = TREE_OPERAND (expr, 0);
820 int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
822 while (TREE_CODE (t) == NOP_EXPR
823 && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
827 t = TREE_OPERAND (t, 0);
828 thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
829 if (thisalign > bestalign)
830 best = t, bestalign = thisalign;
832 return c_alignof (TREE_TYPE (TREE_TYPE (best)));
835 return c_alignof (TREE_TYPE (expr));
838 /* Return either DECL or its known constant value (if it has one). */
841 decl_constant_value (decl)
844 if (/* Don't change a variable array bound or initial value to a constant
845 in a place where a variable is invalid. */
846 current_function_decl != 0
848 && ! TREE_THIS_VOLATILE (decl)
849 && TREE_READONLY (decl)
850 && DECL_INITIAL (decl) != 0
851 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
852 /* This is invalid if initial value is not constant.
853 If it has either a function call, a memory reference,
854 or a variable, then re-evaluating it could give different results. */
855 && TREE_CONSTANT (DECL_INITIAL (decl))
856 /* Check for cases where this is sub-optimal, even though valid. */
857 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR
858 && DECL_MODE (decl) != BLKmode)
859 return DECL_INITIAL (decl);
863 /* Perform default promotions for C data used in expressions.
864 Arrays and functions are converted to pointers;
865 enumeral types or short or char, to int.
866 In addition, manifest constants symbols are replaced by their values. */
869 default_conversion (exp)
872 register tree type = TREE_TYPE (exp);
873 register enum tree_code code = TREE_CODE (type);
875 /* Constants can be used directly unless they're not loadable. */
876 if (TREE_CODE (exp) == CONST_DECL)
877 exp = DECL_INITIAL (exp);
879 /* Replace a nonvolatile const static variable with its value unless
880 it is an array, in which case we must be sure that taking the
881 address of the array produces consistent results. */
882 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
884 exp = decl_constant_value (exp);
885 type = TREE_TYPE (exp);
888 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
891 Do not use STRIP_NOPS here! It will remove conversions from pointer
892 to integer and cause infinite recursion. */
893 while (TREE_CODE (exp) == NON_LVALUE_EXPR
894 || (TREE_CODE (exp) == NOP_EXPR
895 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
896 exp = TREE_OPERAND (exp, 0);
898 /* Normally convert enums to int,
899 but convert wide enums to something wider. */
900 if (code == ENUMERAL_TYPE)
902 type = type_for_size (MAX (TYPE_PRECISION (type),
903 TYPE_PRECISION (integer_type_node)),
905 || (TYPE_PRECISION (type)
906 >= TYPE_PRECISION (integer_type_node)))
907 && TREE_UNSIGNED (type)));
909 return convert (type, exp);
912 if (TREE_CODE (exp) == COMPONENT_REF
913 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
914 /* If it's thinner than an int, promote it like a
915 C_PROMOTING_INTEGER_TYPE_P, otherwise leave it alone. */
916 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
917 TYPE_PRECISION (integer_type_node)))
918 return convert (flag_traditional && TREE_UNSIGNED (type)
919 ? unsigned_type_node : integer_type_node,
922 if (C_PROMOTING_INTEGER_TYPE_P (type))
924 /* Traditionally, unsignedness is preserved in default promotions.
925 Also preserve unsignedness if not really getting any wider. */
926 if (TREE_UNSIGNED (type)
928 || TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
929 return convert (unsigned_type_node, exp);
931 return convert (integer_type_node, exp);
934 if (flag_traditional && !flag_allow_single_precision
935 && TYPE_MAIN_VARIANT (type) == float_type_node)
936 return convert (double_type_node, exp);
938 if (code == VOID_TYPE)
940 error ("void value not ignored as it ought to be");
941 return error_mark_node;
943 if (code == FUNCTION_TYPE)
945 return build_unary_op (ADDR_EXPR, exp, 0);
947 if (code == ARRAY_TYPE)
950 tree restype = TREE_TYPE (type);
955 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r' || DECL_P (exp))
957 constp = TREE_READONLY (exp);
958 volatilep = TREE_THIS_VOLATILE (exp);
961 if (TYPE_QUALS (type) || constp || volatilep)
963 = c_build_qualified_type (restype,
965 | (constp * TYPE_QUAL_CONST)
966 | (volatilep * TYPE_QUAL_VOLATILE));
968 if (TREE_CODE (exp) == INDIRECT_REF)
969 return convert (TYPE_POINTER_TO (restype),
970 TREE_OPERAND (exp, 0));
972 if (TREE_CODE (exp) == COMPOUND_EXPR)
974 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
975 return build (COMPOUND_EXPR, TREE_TYPE (op1),
976 TREE_OPERAND (exp, 0), op1);
980 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
982 error ("invalid use of non-lvalue array");
983 return error_mark_node;
986 ptrtype = build_pointer_type (restype);
988 if (TREE_CODE (exp) == VAR_DECL)
990 /* ??? This is not really quite correct
991 in that the type of the operand of ADDR_EXPR
992 is not the target type of the type of the ADDR_EXPR itself.
993 Question is, can this lossage be avoided? */
994 adr = build1 (ADDR_EXPR, ptrtype, exp);
995 if (mark_addressable (exp) == 0)
996 return error_mark_node;
997 TREE_CONSTANT (adr) = staticp (exp);
998 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1001 /* This way is better for a COMPONENT_REF since it can
1002 simplify the offset for a component. */
1003 adr = build_unary_op (ADDR_EXPR, exp, 1);
1004 return convert (ptrtype, adr);
1009 /* Look up component name in the structure type definition.
1011 If this component name is found indirectly within an anonymous union,
1012 store in *INDIRECT the component which directly contains
1013 that anonymous union. Otherwise, set *INDIRECT to 0. */
1016 lookup_field (type, component, indirect)
1017 tree type, component;
1022 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1023 to the field elements. Use a binary search on this array to quickly
1024 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1025 will always be set for structures which have many elements. */
1027 if (TYPE_LANG_SPECIFIC (type))
1030 tree *field_array = &TYPE_LANG_SPECIFIC (type)->elts[0];
1032 field = TYPE_FIELDS (type);
1034 top = TYPE_LANG_SPECIFIC (type)->len;
1035 while (top - bot > 1)
1037 half = (top - bot + 1) >> 1;
1038 field = field_array[bot+half];
1040 if (DECL_NAME (field) == NULL_TREE)
1042 /* Step through all anon unions in linear fashion. */
1043 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1045 tree anon = 0, junk;
1047 field = field_array[bot++];
1048 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1049 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1050 anon = lookup_field (TREE_TYPE (field), component, &junk);
1052 if (anon != NULL_TREE)
1059 /* Entire record is only anon unions. */
1063 /* Restart the binary search, with new lower bound. */
1067 if (DECL_NAME (field) == component)
1069 if (DECL_NAME (field) < component)
1075 if (DECL_NAME (field_array[bot]) == component)
1076 field = field_array[bot];
1077 else if (DECL_NAME (field) != component)
1082 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1084 if (DECL_NAME (field) == NULL_TREE)
1089 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1090 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1091 anon = lookup_field (TREE_TYPE (field), component, &junk);
1093 if (anon != NULL_TREE)
1100 if (DECL_NAME (field) == component)
1105 *indirect = NULL_TREE;
1109 /* Make an expression to refer to the COMPONENT field of
1110 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1113 build_component_ref (datum, component)
1114 tree datum, component;
1116 register tree type = TREE_TYPE (datum);
1117 register enum tree_code code = TREE_CODE (type);
1118 register tree field = NULL;
1121 /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it
1122 unless we are not to support things not strictly ANSI. */
1123 switch (TREE_CODE (datum))
1127 tree value = build_component_ref (TREE_OPERAND (datum, 1), component);
1128 return build (COMPOUND_EXPR, TREE_TYPE (value),
1129 TREE_OPERAND (datum, 0), value);
1132 return build_conditional_expr
1133 (TREE_OPERAND (datum, 0),
1134 build_component_ref (TREE_OPERAND (datum, 1), component),
1135 build_component_ref (TREE_OPERAND (datum, 2), component));
1141 /* See if there is a field or component with name COMPONENT. */
1143 if (code == RECORD_TYPE || code == UNION_TYPE)
1147 if (!COMPLETE_TYPE_P (type))
1149 incomplete_type_error (NULL_TREE, type);
1150 return error_mark_node;
1153 field = lookup_field (type, component, &indirect);
1157 error ("%s has no member named `%s'",
1158 code == RECORD_TYPE ? "structure" : "union",
1159 IDENTIFIER_POINTER (component));
1160 return error_mark_node;
1162 if (TREE_TYPE (field) == error_mark_node)
1163 return error_mark_node;
1165 /* If FIELD was found buried within an anonymous union,
1166 make one COMPONENT_REF to get that anonymous union,
1167 then fall thru to make a second COMPONENT_REF to get FIELD. */
1170 ref = build (COMPONENT_REF, TREE_TYPE (indirect), datum, indirect);
1171 if (TREE_READONLY (datum) || TREE_READONLY (indirect))
1172 TREE_READONLY (ref) = 1;
1173 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (indirect))
1174 TREE_THIS_VOLATILE (ref) = 1;
1178 ref = build (COMPONENT_REF, TREE_TYPE (field), datum, field);
1180 if (TREE_READONLY (datum) || TREE_READONLY (field))
1181 TREE_READONLY (ref) = 1;
1182 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (field))
1183 TREE_THIS_VOLATILE (ref) = 1;
1187 else if (code != ERROR_MARK)
1188 error ("request for member `%s' in something not a structure or union",
1189 IDENTIFIER_POINTER (component));
1191 return error_mark_node;
1194 /* Given an expression PTR for a pointer, return an expression
1195 for the value pointed to.
1196 ERRORSTRING is the name of the operator to appear in error messages. */
1199 build_indirect_ref (ptr, errorstring)
1201 const char *errorstring;
1203 register tree pointer = default_conversion (ptr);
1204 register tree type = TREE_TYPE (pointer);
1206 if (TREE_CODE (type) == POINTER_TYPE)
1208 if (TREE_CODE (pointer) == ADDR_EXPR
1210 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1211 == TREE_TYPE (type)))
1212 return TREE_OPERAND (pointer, 0);
1215 tree t = TREE_TYPE (type);
1216 register tree ref = build1 (INDIRECT_REF,
1217 TYPE_MAIN_VARIANT (t), pointer);
1219 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1221 error ("dereferencing pointer to incomplete type");
1222 return error_mark_node;
1224 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1225 warning ("dereferencing `void *' pointer");
1227 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1228 so that we get the proper error message if the result is used
1229 to assign to. Also, &* is supposed to be a no-op.
1230 And ANSI C seems to specify that the type of the result
1231 should be the const type. */
1232 /* A de-reference of a pointer to const is not a const. It is valid
1233 to change it via some other pointer. */
1234 TREE_READONLY (ref) = TYPE_READONLY (t);
1235 TREE_SIDE_EFFECTS (ref)
1236 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer) || flag_volatile;
1237 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1241 else if (TREE_CODE (pointer) != ERROR_MARK)
1242 error ("invalid type argument of `%s'", errorstring);
1243 return error_mark_node;
1246 /* This handles expressions of the form "a[i]", which denotes
1249 This is logically equivalent in C to *(a+i), but we may do it differently.
1250 If A is a variable or a member, we generate a primitive ARRAY_REF.
1251 This avoids forcing the array out of registers, and can work on
1252 arrays that are not lvalues (for example, members of structures returned
1256 build_array_ref (array, index)
1261 error ("subscript missing in array reference");
1262 return error_mark_node;
1265 if (TREE_TYPE (array) == error_mark_node
1266 || TREE_TYPE (index) == error_mark_node)
1267 return error_mark_node;
1269 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
1270 && TREE_CODE (array) != INDIRECT_REF)
1274 /* Subscripting with type char is likely to lose
1275 on a machine where chars are signed.
1276 So warn on any machine, but optionally.
1277 Don't warn for unsigned char since that type is safe.
1278 Don't warn for signed char because anyone who uses that
1279 must have done so deliberately. */
1280 if (warn_char_subscripts
1281 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1282 warning ("array subscript has type `char'");
1284 /* Apply default promotions *after* noticing character types. */
1285 index = default_conversion (index);
1287 /* Require integer *after* promotion, for sake of enums. */
1288 if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE)
1290 error ("array subscript is not an integer");
1291 return error_mark_node;
1294 /* An array that is indexed by a non-constant
1295 cannot be stored in a register; we must be able to do
1296 address arithmetic on its address.
1297 Likewise an array of elements of variable size. */
1298 if (TREE_CODE (index) != INTEGER_CST
1299 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1300 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1302 if (mark_addressable (array) == 0)
1303 return error_mark_node;
1305 /* An array that is indexed by a constant value which is not within
1306 the array bounds cannot be stored in a register either; because we
1307 would get a crash in store_bit_field/extract_bit_field when trying
1308 to access a non-existent part of the register. */
1309 if (TREE_CODE (index) == INTEGER_CST
1310 && TYPE_VALUES (TREE_TYPE (array))
1311 && ! int_fits_type_p (index, TYPE_VALUES (TREE_TYPE (array))))
1313 if (mark_addressable (array) == 0)
1314 return error_mark_node;
1320 while (TREE_CODE (foo) == COMPONENT_REF)
1321 foo = TREE_OPERAND (foo, 0);
1322 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
1323 pedwarn ("ISO C forbids subscripting `register' array");
1324 else if (! flag_isoc99 && ! lvalue_p (foo))
1325 pedwarn ("ISO C89 forbids subscripting non-lvalue array");
1328 type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array)));
1329 rval = build (ARRAY_REF, type, array, index);
1330 /* Array ref is const/volatile if the array elements are
1331 or if the array is. */
1332 TREE_READONLY (rval)
1333 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1334 | TREE_READONLY (array));
1335 TREE_SIDE_EFFECTS (rval)
1336 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1337 | TREE_SIDE_EFFECTS (array));
1338 TREE_THIS_VOLATILE (rval)
1339 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1340 /* This was added by rms on 16 Nov 91.
1341 It fixes vol struct foo *a; a->elts[1]
1342 in an inline function.
1343 Hope it doesn't break something else. */
1344 | TREE_THIS_VOLATILE (array));
1345 return require_complete_type (fold (rval));
1349 tree ar = default_conversion (array);
1350 tree ind = default_conversion (index);
1352 /* Do the same warning check as above, but only on the part that's
1353 syntactically the index and only if it is also semantically
1355 if (warn_char_subscripts
1356 && TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE
1357 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1358 warning ("subscript has type `char'");
1360 /* Put the integer in IND to simplify error checking. */
1361 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
1368 if (ar == error_mark_node)
1371 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE
1372 || TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) == FUNCTION_TYPE)
1374 error ("subscripted value is neither array nor pointer");
1375 return error_mark_node;
1377 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
1379 error ("array subscript is not an integer");
1380 return error_mark_node;
1383 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0),
1388 /* Build an external reference to identifier ID. FUN indicates
1389 whether this will be used for a function call. */
1391 build_external_ref (id, fun)
1396 tree decl = lookup_name (id);
1397 tree objc_ivar = lookup_objc_ivar (id);
1399 if (!decl || decl == error_mark_node || C_DECL_ANTICIPATED (decl))
1405 if (!decl || decl == error_mark_node)
1406 /* Ordinary implicit function declaration. */
1407 ref = implicitly_declare (id);
1410 /* Implicit declaration of built-in function. Don't
1411 change the built-in declaration, but don't let this
1412 go by silently, either. */
1413 implicit_decl_warning (id);
1415 /* only issue this warning once */
1416 C_DECL_ANTICIPATED (decl) = 0;
1422 /* Reference to undeclared variable, including reference to
1423 builtin outside of function-call context. */
1424 if (current_function_decl == 0)
1425 error ("`%s' undeclared here (not in a function)",
1426 IDENTIFIER_POINTER (id));
1429 if (IDENTIFIER_GLOBAL_VALUE (id) != error_mark_node
1430 || IDENTIFIER_ERROR_LOCUS (id) != current_function_decl)
1432 error ("`%s' undeclared (first use in this function)",
1433 IDENTIFIER_POINTER (id));
1435 if (! undeclared_variable_notice)
1437 error ("(Each undeclared identifier is reported only once");
1438 error ("for each function it appears in.)");
1439 undeclared_variable_notice = 1;
1442 IDENTIFIER_GLOBAL_VALUE (id) = error_mark_node;
1443 IDENTIFIER_ERROR_LOCUS (id) = current_function_decl;
1445 return error_mark_node;
1450 /* Properly declared variable or function reference. */
1453 else if (decl != objc_ivar && IDENTIFIER_LOCAL_VALUE (id))
1455 warning ("local declaration of `%s' hides instance variable",
1456 IDENTIFIER_POINTER (id));
1463 if (TREE_TYPE (ref) == error_mark_node)
1464 return error_mark_node;
1466 assemble_external (ref);
1467 TREE_USED (ref) = 1;
1469 if (TREE_CODE (ref) == CONST_DECL)
1471 ref = DECL_INITIAL (ref);
1472 TREE_CONSTANT (ref) = 1;
1478 /* Build a function call to function FUNCTION with parameters PARAMS.
1479 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1480 TREE_VALUE of each node is a parameter-expression.
1481 FUNCTION's data type may be a function type or a pointer-to-function. */
1484 build_function_call (function, params)
1485 tree function, params;
1487 register tree fntype, fundecl = 0;
1488 register tree coerced_params;
1489 tree name = NULL_TREE, assembler_name = NULL_TREE, result;
1491 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1492 STRIP_TYPE_NOPS (function);
1494 /* Convert anything with function type to a pointer-to-function. */
1495 if (TREE_CODE (function) == FUNCTION_DECL)
1497 name = DECL_NAME (function);
1498 assembler_name = DECL_ASSEMBLER_NAME (function);
1500 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1501 (because calling an inline function does not mean the function
1502 needs to be separately compiled). */
1503 fntype = build_type_variant (TREE_TYPE (function),
1504 TREE_READONLY (function),
1505 TREE_THIS_VOLATILE (function));
1507 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
1510 function = default_conversion (function);
1512 fntype = TREE_TYPE (function);
1514 if (TREE_CODE (fntype) == ERROR_MARK)
1515 return error_mark_node;
1517 if (!(TREE_CODE (fntype) == POINTER_TYPE
1518 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
1520 error ("called object is not a function");
1521 return error_mark_node;
1524 /* fntype now gets the type of function pointed to. */
1525 fntype = TREE_TYPE (fntype);
1527 /* Convert the parameters to the types declared in the
1528 function prototype, or apply default promotions. */
1531 = convert_arguments (TYPE_ARG_TYPES (fntype), params, name, fundecl);
1533 /* Check for errors in format strings. */
1535 if (warn_format && (name || assembler_name))
1536 check_function_format (NULL, name, assembler_name, coerced_params);
1538 /* Recognize certain built-in functions so we can make tree-codes
1539 other than CALL_EXPR. We do this when it enables fold-const.c
1540 to do something useful. */
1542 if (TREE_CODE (function) == ADDR_EXPR
1543 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
1544 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
1546 result = expand_tree_builtin (TREE_OPERAND (function, 0),
1547 params, coerced_params);
1552 result = build (CALL_EXPR, TREE_TYPE (fntype),
1553 function, coerced_params, NULL_TREE);
1555 TREE_SIDE_EFFECTS (result) = 1;
1556 if (VOID_TYPE_P (TREE_TYPE (result)))
1558 return require_complete_type (result);
1561 /* Convert the argument expressions in the list VALUES
1562 to the types in the list TYPELIST. The result is a list of converted
1563 argument expressions.
1565 If TYPELIST is exhausted, or when an element has NULL as its type,
1566 perform the default conversions.
1568 PARMLIST is the chain of parm decls for the function being called.
1569 It may be 0, if that info is not available.
1570 It is used only for generating error messages.
1572 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1574 This is also where warnings about wrong number of args are generated.
1576 Both VALUES and the returned value are chains of TREE_LIST nodes
1577 with the elements of the list in the TREE_VALUE slots of those nodes. */
1580 convert_arguments (typelist, values, name, fundecl)
1581 tree typelist, values, name, fundecl;
1583 register tree typetail, valtail;
1584 register tree result = NULL;
1587 /* Scan the given expressions and types, producing individual
1588 converted arguments and pushing them on RESULT in reverse order. */
1590 for (valtail = values, typetail = typelist, parmnum = 0;
1592 valtail = TREE_CHAIN (valtail), parmnum++)
1594 register tree type = typetail ? TREE_VALUE (typetail) : 0;
1595 register tree val = TREE_VALUE (valtail);
1597 if (type == void_type_node)
1600 error ("too many arguments to function `%s'",
1601 IDENTIFIER_POINTER (name));
1603 error ("too many arguments to function");
1607 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1608 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1609 to convert automatically to a pointer. */
1610 if (TREE_CODE (val) == NON_LVALUE_EXPR)
1611 val = TREE_OPERAND (val, 0);
1613 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
1614 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE)
1615 val = default_conversion (val);
1617 val = require_complete_type (val);
1621 /* Formal parm type is specified by a function prototype. */
1624 if (!COMPLETE_TYPE_P (type))
1626 error ("type of formal parameter %d is incomplete", parmnum + 1);
1631 /* Optionally warn about conversions that
1632 differ from the default conversions. */
1633 if (warn_conversion)
1635 int formal_prec = TYPE_PRECISION (type);
1637 if (INTEGRAL_TYPE_P (type)
1638 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1639 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1640 else if (TREE_CODE (type) == COMPLEX_TYPE
1641 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1642 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1643 else if (TREE_CODE (type) == REAL_TYPE
1644 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1645 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1646 else if (TREE_CODE (type) == REAL_TYPE
1647 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
1648 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1649 /* ??? At some point, messages should be written about
1650 conversions between complex types, but that's too messy
1652 else if (TREE_CODE (type) == REAL_TYPE
1653 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1655 /* Warn if any argument is passed as `float',
1656 since without a prototype it would be `double'. */
1657 if (formal_prec == TYPE_PRECISION (float_type_node))
1658 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1660 /* Detect integer changing in width or signedness. */
1661 else if (INTEGRAL_TYPE_P (type)
1662 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1664 tree would_have_been = default_conversion (val);
1665 tree type1 = TREE_TYPE (would_have_been);
1667 if (TREE_CODE (type) == ENUMERAL_TYPE
1668 && type == TREE_TYPE (val))
1669 /* No warning if function asks for enum
1670 and the actual arg is that enum type. */
1672 else if (formal_prec != TYPE_PRECISION (type1))
1673 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1674 else if (TREE_UNSIGNED (type) == TREE_UNSIGNED (type1))
1676 /* Don't complain if the formal parameter type
1677 is an enum, because we can't tell now whether
1678 the value was an enum--even the same enum. */
1679 else if (TREE_CODE (type) == ENUMERAL_TYPE)
1681 else if (TREE_CODE (val) == INTEGER_CST
1682 && int_fits_type_p (val, type))
1683 /* Change in signedness doesn't matter
1684 if a constant value is unaffected. */
1686 /* Likewise for a constant in a NOP_EXPR. */
1687 else if (TREE_CODE (val) == NOP_EXPR
1688 && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST
1689 && int_fits_type_p (TREE_OPERAND (val, 0), type))
1691 #if 0 /* We never get such tree structure here. */
1692 else if (TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE
1693 && int_fits_type_p (TYPE_MIN_VALUE (TREE_TYPE (val)), type)
1694 && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE (val)), type))
1695 /* Change in signedness doesn't matter
1696 if an enum value is unaffected. */
1699 /* If the value is extended from a narrower
1700 unsigned type, it doesn't matter whether we
1701 pass it as signed or unsigned; the value
1702 certainly is the same either way. */
1703 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
1704 && TREE_UNSIGNED (TREE_TYPE (val)))
1706 else if (TREE_UNSIGNED (type))
1707 warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1);
1709 warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1);
1713 parmval = convert_for_assignment (type, val,
1714 (char *) 0, /* arg passing */
1715 fundecl, name, parmnum + 1);
1717 if (PROMOTE_PROTOTYPES
1718 && (TREE_CODE (type) == INTEGER_TYPE
1719 || TREE_CODE (type) == ENUMERAL_TYPE)
1720 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
1721 parmval = default_conversion (parmval);
1723 result = tree_cons (NULL_TREE, parmval, result);
1725 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
1726 && (TYPE_PRECISION (TREE_TYPE (val))
1727 < TYPE_PRECISION (double_type_node)))
1728 /* Convert `float' to `double'. */
1729 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
1731 /* Convert `short' and `char' to full-size `int'. */
1732 result = tree_cons (NULL_TREE, default_conversion (val), result);
1735 typetail = TREE_CHAIN (typetail);
1738 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
1741 error ("too few arguments to function `%s'",
1742 IDENTIFIER_POINTER (name));
1744 error ("too few arguments to function");
1747 return nreverse (result);
1750 /* This is the entry point used by the parser
1751 for binary operators in the input.
1752 In addition to constructing the expression,
1753 we check for operands that were written with other binary operators
1754 in a way that is likely to confuse the user. */
1757 parser_build_binary_op (code, arg1, arg2)
1758 enum tree_code code;
1761 tree result = build_binary_op (code, arg1, arg2, 1);
1764 char class1 = TREE_CODE_CLASS (TREE_CODE (arg1));
1765 char class2 = TREE_CODE_CLASS (TREE_CODE (arg2));
1766 enum tree_code code1 = ERROR_MARK;
1767 enum tree_code code2 = ERROR_MARK;
1769 if (class1 == 'e' || class1 == '1'
1770 || class1 == '2' || class1 == '<')
1771 code1 = C_EXP_ORIGINAL_CODE (arg1);
1772 if (class2 == 'e' || class2 == '1'
1773 || class2 == '2' || class2 == '<')
1774 code2 = C_EXP_ORIGINAL_CODE (arg2);
1776 /* Check for cases such as x+y<<z which users are likely
1777 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1778 is cleared to prevent these warnings. */
1779 if (warn_parentheses)
1781 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
1783 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1784 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1785 warning ("suggest parentheses around + or - inside shift");
1788 if (code == TRUTH_ORIF_EXPR)
1790 if (code1 == TRUTH_ANDIF_EXPR
1791 || code2 == TRUTH_ANDIF_EXPR)
1792 warning ("suggest parentheses around && within ||");
1795 if (code == BIT_IOR_EXPR)
1797 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
1798 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1799 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
1800 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1801 warning ("suggest parentheses around arithmetic in operand of |");
1802 /* Check cases like x|y==z */
1803 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1804 warning ("suggest parentheses around comparison in operand of |");
1807 if (code == BIT_XOR_EXPR)
1809 if (code1 == BIT_AND_EXPR
1810 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1811 || code2 == BIT_AND_EXPR
1812 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1813 warning ("suggest parentheses around arithmetic in operand of ^");
1814 /* Check cases like x^y==z */
1815 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1816 warning ("suggest parentheses around comparison in operand of ^");
1819 if (code == BIT_AND_EXPR)
1821 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1822 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1823 warning ("suggest parentheses around + or - in operand of &");
1824 /* Check cases like x&y==z */
1825 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1826 warning ("suggest parentheses around comparison in operand of &");
1830 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1831 if (TREE_CODE_CLASS (code) == '<' && extra_warnings
1832 && (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<'))
1833 warning ("comparisons like X<=Y<=Z do not have their mathematical meaning");
1835 unsigned_conversion_warning (result, arg1);
1836 unsigned_conversion_warning (result, arg2);
1837 overflow_warning (result);
1839 class = TREE_CODE_CLASS (TREE_CODE (result));
1841 /* Record the code that was specified in the source,
1842 for the sake of warnings about confusing nesting. */
1843 if (class == 'e' || class == '1'
1844 || class == '2' || class == '<')
1845 C_SET_EXP_ORIGINAL_CODE (result, code);
1848 int flag = TREE_CONSTANT (result);
1849 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1850 so that convert_for_assignment wouldn't strip it.
1851 That way, we got warnings for things like p = (1 - 1).
1852 But it turns out we should not get those warnings. */
1853 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
1854 C_SET_EXP_ORIGINAL_CODE (result, code);
1855 TREE_CONSTANT (result) = flag;
1861 /* Build a binary-operation expression without default conversions.
1862 CODE is the kind of expression to build.
1863 This function differs from `build' in several ways:
1864 the data type of the result is computed and recorded in it,
1865 warnings are generated if arg data types are invalid,
1866 special handling for addition and subtraction of pointers is known,
1867 and some optimization is done (operations on narrow ints
1868 are done in the narrower type when that gives the same result).
1869 Constant folding is also done before the result is returned.
1871 Note that the operands will never have enumeral types, or function
1872 or array types, because either they will have the default conversions
1873 performed or they have both just been converted to some other type in which
1874 the arithmetic is to be done. */
1877 build_binary_op (code, orig_op0, orig_op1, convert_p)
1878 enum tree_code code;
1879 tree orig_op0, orig_op1;
1883 register enum tree_code code0, code1;
1886 /* Expression code to give to the expression when it is built.
1887 Normally this is CODE, which is what the caller asked for,
1888 but in some special cases we change it. */
1889 register enum tree_code resultcode = code;
1891 /* Data type in which the computation is to be performed.
1892 In the simplest cases this is the common type of the arguments. */
1893 register tree result_type = NULL;
1895 /* Nonzero means operands have already been type-converted
1896 in whatever way is necessary.
1897 Zero means they need to be converted to RESULT_TYPE. */
1900 /* Nonzero means create the expression with this type, rather than
1902 tree build_type = 0;
1904 /* Nonzero means after finally constructing the expression
1905 convert it to this type. */
1906 tree final_type = 0;
1908 /* Nonzero if this is an operation like MIN or MAX which can
1909 safely be computed in short if both args are promoted shorts.
1910 Also implies COMMON.
1911 -1 indicates a bitwise operation; this makes a difference
1912 in the exact conditions for when it is safe to do the operation
1913 in a narrower mode. */
1916 /* Nonzero if this is a comparison operation;
1917 if both args are promoted shorts, compare the original shorts.
1918 Also implies COMMON. */
1919 int short_compare = 0;
1921 /* Nonzero if this is a right-shift operation, which can be computed on the
1922 original short and then promoted if the operand is a promoted short. */
1923 int short_shift = 0;
1925 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1930 op0 = default_conversion (orig_op0);
1931 op1 = default_conversion (orig_op1);
1939 type0 = TREE_TYPE (op0);
1940 type1 = TREE_TYPE (op1);
1942 /* The expression codes of the data types of the arguments tell us
1943 whether the arguments are integers, floating, pointers, etc. */
1944 code0 = TREE_CODE (type0);
1945 code1 = TREE_CODE (type1);
1947 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1948 STRIP_TYPE_NOPS (op0);
1949 STRIP_TYPE_NOPS (op1);
1951 /* If an error was already reported for one of the arguments,
1952 avoid reporting another error. */
1954 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
1955 return error_mark_node;
1960 /* Handle the pointer + int case. */
1961 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
1962 return pointer_int_sum (PLUS_EXPR, op0, op1);
1963 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
1964 return pointer_int_sum (PLUS_EXPR, op1, op0);
1970 /* Subtraction of two similar pointers.
1971 We must subtract them as integers, then divide by object size. */
1972 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
1973 && comp_target_types (type0, type1))
1974 return pointer_diff (op0, op1);
1975 /* Handle pointer minus int. Just like pointer plus int. */
1976 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
1977 return pointer_int_sum (MINUS_EXPR, op0, op1);
1986 case TRUNC_DIV_EXPR:
1988 case FLOOR_DIV_EXPR:
1989 case ROUND_DIV_EXPR:
1990 case EXACT_DIV_EXPR:
1991 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
1992 || code0 == COMPLEX_TYPE)
1993 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
1994 || code1 == COMPLEX_TYPE))
1996 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
1997 resultcode = RDIV_EXPR;
1999 /* Although it would be tempting to shorten always here, that
2000 loses on some targets, since the modulo instruction is
2001 undefined if the quotient can't be represented in the
2002 computation mode. We shorten only if unsigned or if
2003 dividing by something we know != -1. */
2004 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
2005 || (TREE_CODE (op1) == INTEGER_CST
2006 && ! integer_all_onesp (op1)));
2012 case BIT_ANDTC_EXPR:
2015 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2017 /* If one operand is a constant, and the other is a short type
2018 that has been converted to an int,
2019 really do the work in the short type and then convert the
2020 result to int. If we are lucky, the constant will be 0 or 1
2021 in the short type, making the entire operation go away. */
2022 if (TREE_CODE (op0) == INTEGER_CST
2023 && TREE_CODE (op1) == NOP_EXPR
2024 && TYPE_PRECISION (type1) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))
2025 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0))))
2027 final_type = result_type;
2028 op1 = TREE_OPERAND (op1, 0);
2029 result_type = TREE_TYPE (op1);
2031 if (TREE_CODE (op1) == INTEGER_CST
2032 && TREE_CODE (op0) == NOP_EXPR
2033 && TYPE_PRECISION (type0) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))
2034 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2036 final_type = result_type;
2037 op0 = TREE_OPERAND (op0, 0);
2038 result_type = TREE_TYPE (op0);
2042 case TRUNC_MOD_EXPR:
2043 case FLOOR_MOD_EXPR:
2044 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2046 /* Although it would be tempting to shorten always here, that loses
2047 on some targets, since the modulo instruction is undefined if the
2048 quotient can't be represented in the computation mode. We shorten
2049 only if unsigned or if dividing by something we know != -1. */
2050 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
2051 || (TREE_CODE (op1) == INTEGER_CST
2052 && ! integer_all_onesp (op1)));
2057 case TRUTH_ANDIF_EXPR:
2058 case TRUTH_ORIF_EXPR:
2059 case TRUTH_AND_EXPR:
2061 case TRUTH_XOR_EXPR:
2062 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
2063 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2064 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
2065 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2067 /* Result of these operations is always an int,
2068 but that does not mean the operands should be
2069 converted to ints! */
2070 result_type = integer_type_node;
2071 op0 = truthvalue_conversion (op0);
2072 op1 = truthvalue_conversion (op1);
2077 /* Shift operations: result has same type as first operand;
2078 always convert second operand to int.
2079 Also set SHORT_SHIFT if shifting rightward. */
2082 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2084 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2086 if (tree_int_cst_sgn (op1) < 0)
2087 warning ("right shift count is negative");
2090 if (! integer_zerop (op1))
2093 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2094 warning ("right shift count >= width of type");
2098 /* Use the type of the value to be shifted.
2099 This is what most traditional C compilers do. */
2100 result_type = type0;
2101 /* Unless traditional, convert the shift-count to an integer,
2102 regardless of size of value being shifted. */
2103 if (! flag_traditional)
2105 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2106 op1 = convert (integer_type_node, op1);
2107 /* Avoid converting op1 to result_type later. */
2114 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2116 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2118 if (tree_int_cst_sgn (op1) < 0)
2119 warning ("left shift count is negative");
2121 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2122 warning ("left shift count >= width of type");
2125 /* Use the type of the value to be shifted.
2126 This is what most traditional C compilers do. */
2127 result_type = type0;
2128 /* Unless traditional, convert the shift-count to an integer,
2129 regardless of size of value being shifted. */
2130 if (! flag_traditional)
2132 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2133 op1 = convert (integer_type_node, op1);
2134 /* Avoid converting op1 to result_type later. */
2142 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2144 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2146 if (tree_int_cst_sgn (op1) < 0)
2147 warning ("shift count is negative");
2148 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2149 warning ("shift count >= width of type");
2152 /* Use the type of the value to be shifted.
2153 This is what most traditional C compilers do. */
2154 result_type = type0;
2155 /* Unless traditional, convert the shift-count to an integer,
2156 regardless of size of value being shifted. */
2157 if (! flag_traditional)
2159 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2160 op1 = convert (integer_type_node, op1);
2161 /* Avoid converting op1 to result_type later. */
2169 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
2170 warning ("comparing floating point with == or != is unsafe");
2171 /* Result of comparison is always int,
2172 but don't convert the args to int! */
2173 build_type = integer_type_node;
2174 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2175 || code0 == COMPLEX_TYPE)
2176 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2177 || code1 == COMPLEX_TYPE))
2179 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2181 register tree tt0 = TREE_TYPE (type0);
2182 register tree tt1 = TREE_TYPE (type1);
2183 /* Anything compares with void *. void * compares with anything.
2184 Otherwise, the targets must be compatible
2185 and both must be object or both incomplete. */
2186 if (comp_target_types (type0, type1))
2187 result_type = common_type (type0, type1);
2188 else if (VOID_TYPE_P (tt0))
2190 /* op0 != orig_op0 detects the case of something
2191 whose value is 0 but which isn't a valid null ptr const. */
2192 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
2193 && TREE_CODE (tt1) == FUNCTION_TYPE)
2194 pedwarn ("ISO C forbids comparison of `void *' with function pointer");
2196 else if (VOID_TYPE_P (tt1))
2198 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
2199 && TREE_CODE (tt0) == FUNCTION_TYPE)
2200 pedwarn ("ISO C forbids comparison of `void *' with function pointer");
2203 pedwarn ("comparison of distinct pointer types lacks a cast");
2205 if (result_type == NULL_TREE)
2206 result_type = ptr_type_node;
2208 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2209 && integer_zerop (op1))
2210 result_type = type0;
2211 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2212 && integer_zerop (op0))
2213 result_type = type1;
2214 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2216 result_type = type0;
2217 if (! flag_traditional)
2218 pedwarn ("comparison between pointer and integer");
2220 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2222 result_type = type1;
2223 if (! flag_traditional)
2224 pedwarn ("comparison between pointer and integer");
2230 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2231 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2233 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2235 if (comp_target_types (type0, type1))
2237 result_type = common_type (type0, type1);
2239 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2240 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
2244 result_type = ptr_type_node;
2245 pedwarn ("comparison of distinct pointer types lacks a cast");
2254 build_type = integer_type_node;
2255 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2256 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2258 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2260 if (comp_target_types (type0, type1))
2262 result_type = common_type (type0, type1);
2263 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
2264 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
2265 pedwarn ("comparison of complete and incomplete pointers");
2267 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2268 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
2272 result_type = ptr_type_node;
2273 pedwarn ("comparison of distinct pointer types lacks a cast");
2276 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2277 && integer_zerop (op1))
2279 result_type = type0;
2280 if (pedantic || extra_warnings)
2281 pedwarn ("ordered comparison of pointer with integer zero");
2283 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2284 && integer_zerop (op0))
2286 result_type = type1;
2288 pedwarn ("ordered comparison of pointer with integer zero");
2290 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2292 result_type = type0;
2293 if (! flag_traditional)
2294 pedwarn ("comparison between pointer and integer");
2296 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2298 result_type = type1;
2299 if (! flag_traditional)
2300 pedwarn ("comparison between pointer and integer");
2304 case UNORDERED_EXPR:
2311 build_type = integer_type_node;
2312 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
2314 error ("unordered comparison on non-floating point argument");
2315 return error_mark_node;
2324 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2326 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2328 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
2330 if (shorten || common || short_compare)
2331 result_type = common_type (type0, type1);
2333 /* For certain operations (which identify themselves by shorten != 0)
2334 if both args were extended from the same smaller type,
2335 do the arithmetic in that type and then extend.
2337 shorten !=0 and !=1 indicates a bitwise operation.
2338 For them, this optimization is safe only if
2339 both args are zero-extended or both are sign-extended.
2340 Otherwise, we might change the result.
2341 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2342 but calculated in (unsigned short) it would be (unsigned short)-1. */
2344 if (shorten && none_complex)
2346 int unsigned0, unsigned1;
2347 tree arg0 = get_narrower (op0, &unsigned0);
2348 tree arg1 = get_narrower (op1, &unsigned1);
2349 /* UNS is 1 if the operation to be done is an unsigned one. */
2350 int uns = TREE_UNSIGNED (result_type);
2353 final_type = result_type;
2355 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2356 but it *requires* conversion to FINAL_TYPE. */
2358 if ((TYPE_PRECISION (TREE_TYPE (op0))
2359 == TYPE_PRECISION (TREE_TYPE (arg0)))
2360 && TREE_TYPE (op0) != final_type)
2361 unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
2362 if ((TYPE_PRECISION (TREE_TYPE (op1))
2363 == TYPE_PRECISION (TREE_TYPE (arg1)))
2364 && TREE_TYPE (op1) != final_type)
2365 unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
2367 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2369 /* For bitwise operations, signedness of nominal type
2370 does not matter. Consider only how operands were extended. */
2374 /* Note that in all three cases below we refrain from optimizing
2375 an unsigned operation on sign-extended args.
2376 That would not be valid. */
2378 /* Both args variable: if both extended in same way
2379 from same width, do it in that width.
2380 Do it unsigned if args were zero-extended. */
2381 if ((TYPE_PRECISION (TREE_TYPE (arg0))
2382 < TYPE_PRECISION (result_type))
2383 && (TYPE_PRECISION (TREE_TYPE (arg1))
2384 == TYPE_PRECISION (TREE_TYPE (arg0)))
2385 && unsigned0 == unsigned1
2386 && (unsigned0 || !uns))
2388 = signed_or_unsigned_type (unsigned0,
2389 common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
2390 else if (TREE_CODE (arg0) == INTEGER_CST
2391 && (unsigned1 || !uns)
2392 && (TYPE_PRECISION (TREE_TYPE (arg1))
2393 < TYPE_PRECISION (result_type))
2394 && (type = signed_or_unsigned_type (unsigned1,
2396 int_fits_type_p (arg0, type)))
2398 else if (TREE_CODE (arg1) == INTEGER_CST
2399 && (unsigned0 || !uns)
2400 && (TYPE_PRECISION (TREE_TYPE (arg0))
2401 < TYPE_PRECISION (result_type))
2402 && (type = signed_or_unsigned_type (unsigned0,
2404 int_fits_type_p (arg1, type)))
2408 /* Shifts can be shortened if shifting right. */
2413 tree arg0 = get_narrower (op0, &unsigned_arg);
2415 final_type = result_type;
2417 if (arg0 == op0 && final_type == TREE_TYPE (op0))
2418 unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
2420 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
2421 /* We can shorten only if the shift count is less than the
2422 number of bits in the smaller type size. */
2423 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
2424 /* If arg is sign-extended and then unsigned-shifted,
2425 we can simulate this with a signed shift in arg's type
2426 only if the extended result is at least twice as wide
2427 as the arg. Otherwise, the shift could use up all the
2428 ones made by sign-extension and bring in zeros.
2429 We can't optimize that case at all, but in most machines
2430 it never happens because available widths are 2**N. */
2431 && (!TREE_UNSIGNED (final_type)
2433 || (2 * TYPE_PRECISION (TREE_TYPE (arg0))
2434 <= TYPE_PRECISION (result_type))))
2436 /* Do an unsigned shift if the operand was zero-extended. */
2438 = signed_or_unsigned_type (unsigned_arg,
2440 /* Convert value-to-be-shifted to that type. */
2441 if (TREE_TYPE (op0) != result_type)
2442 op0 = convert (result_type, op0);
2447 /* Comparison operations are shortened too but differently.
2448 They identify themselves by setting short_compare = 1. */
2452 /* Don't write &op0, etc., because that would prevent op0
2453 from being kept in a register.
2454 Instead, make copies of the our local variables and
2455 pass the copies by reference, then copy them back afterward. */
2456 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
2457 enum tree_code xresultcode = resultcode;
2459 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
2464 op0 = xop0, op1 = xop1;
2466 resultcode = xresultcode;
2468 if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare != 0)
2469 && skip_evaluation == 0)
2471 int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0));
2472 int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1));
2473 int unsignedp0, unsignedp1;
2474 tree primop0 = get_narrower (op0, &unsignedp0);
2475 tree primop1 = get_narrower (op1, &unsignedp1);
2479 STRIP_TYPE_NOPS (xop0);
2480 STRIP_TYPE_NOPS (xop1);
2482 /* Give warnings for comparisons between signed and unsigned
2483 quantities that may fail.
2485 Do the checking based on the original operand trees, so that
2486 casts will be considered, but default promotions won't be.
2488 Do not warn if the comparison is being done in a signed type,
2489 since the signed type will only be chosen if it can represent
2490 all the values of the unsigned type. */
2491 if (! TREE_UNSIGNED (result_type))
2493 /* Do not warn if both operands are the same signedness. */
2494 else if (op0_signed == op1_signed)
2501 sop = xop0, uop = xop1;
2503 sop = xop1, uop = xop0;
2505 /* Do not warn if the signed quantity is an
2506 unsuffixed integer literal (or some static
2507 constant expression involving such literals or a
2508 conditional expression involving such literals)
2509 and it is non-negative. */
2510 if (tree_expr_nonnegative_p (sop))
2512 /* Do not warn if the comparison is an equality operation,
2513 the unsigned quantity is an integral constant, and it
2514 would fit in the result if the result were signed. */
2515 else if (TREE_CODE (uop) == INTEGER_CST
2516 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
2517 && int_fits_type_p (uop, signed_type (result_type)))
2519 /* Do not warn if the unsigned quantity is an enumeration
2520 constant and its maximum value would fit in the result
2521 if the result were signed. */
2522 else if (TREE_CODE (uop) == INTEGER_CST
2523 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
2524 && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE(uop)),
2525 signed_type (result_type)))
2528 warning ("comparison between signed and unsigned");
2531 /* Warn if two unsigned values are being compared in a size
2532 larger than their original size, and one (and only one) is the
2533 result of a `~' operator. This comparison will always fail.
2535 Also warn if one operand is a constant, and the constant
2536 does not have all bits set that are set in the ~ operand
2537 when it is extended. */
2539 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
2540 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
2542 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
2543 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
2546 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
2549 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
2552 HOST_WIDE_INT constant, mask;
2553 int unsignedp, bits;
2555 if (host_integerp (primop0, 0))
2558 unsignedp = unsignedp1;
2559 constant = tree_low_cst (primop0, 0);
2564 unsignedp = unsignedp0;
2565 constant = tree_low_cst (primop1, 0);
2568 bits = TYPE_PRECISION (TREE_TYPE (primop));
2569 if (bits < TYPE_PRECISION (result_type)
2570 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
2572 mask = (~ (HOST_WIDE_INT) 0) << bits;
2573 if ((mask & constant) != mask)
2574 warning ("comparison of promoted ~unsigned with constant");
2577 else if (unsignedp0 && unsignedp1
2578 && (TYPE_PRECISION (TREE_TYPE (primop0))
2579 < TYPE_PRECISION (result_type))
2580 && (TYPE_PRECISION (TREE_TYPE (primop1))
2581 < TYPE_PRECISION (result_type)))
2582 warning ("comparison of promoted ~unsigned with unsigned");
2588 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2589 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2590 Then the expression will be built.
2591 It will be given type FINAL_TYPE if that is nonzero;
2592 otherwise, it will be given type RESULT_TYPE. */
2596 binary_op_error (code);
2597 return error_mark_node;
2602 if (TREE_TYPE (op0) != result_type)
2603 op0 = convert (result_type, op0);
2604 if (TREE_TYPE (op1) != result_type)
2605 op1 = convert (result_type, op1);
2608 if (build_type == NULL_TREE)
2609 build_type = result_type;
2612 register tree result = build (resultcode, build_type, op0, op1);
2613 register tree folded;
2615 folded = fold (result);
2616 if (folded == result)
2617 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2618 if (final_type != 0)
2619 return convert (final_type, folded);
2624 /* Return a tree for the sum or difference (RESULTCODE says which)
2625 of pointer PTROP and integer INTOP. */
2628 pointer_int_sum (resultcode, ptrop, intop)
2629 enum tree_code resultcode;
2630 register tree ptrop, intop;
2634 register tree result;
2635 register tree folded;
2637 /* The result is a pointer of the same type that is being added. */
2639 register tree result_type = TREE_TYPE (ptrop);
2641 if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
2643 if (pedantic || warn_pointer_arith)
2644 pedwarn ("pointer of type `void *' used in arithmetic");
2645 size_exp = integer_one_node;
2647 else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
2649 if (pedantic || warn_pointer_arith)
2650 pedwarn ("pointer to a function used in arithmetic");
2651 size_exp = integer_one_node;
2654 size_exp = c_size_in_bytes (TREE_TYPE (result_type));
2656 /* If what we are about to multiply by the size of the elements
2657 contains a constant term, apply distributive law
2658 and multiply that constant term separately.
2659 This helps produce common subexpressions. */
2661 if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
2662 && ! TREE_CONSTANT (intop)
2663 && TREE_CONSTANT (TREE_OPERAND (intop, 1))
2664 && TREE_CONSTANT (size_exp)
2665 /* If the constant comes from pointer subtraction,
2666 skip this optimization--it would cause an error. */
2667 && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE
2668 /* If the constant is unsigned, and smaller than the pointer size,
2669 then we must skip this optimization. This is because it could cause
2670 an overflow error if the constant is negative but INTOP is not. */
2671 && (! TREE_UNSIGNED (TREE_TYPE (intop))
2672 || (TYPE_PRECISION (TREE_TYPE (intop))
2673 == TYPE_PRECISION (TREE_TYPE (ptrop)))))
2675 enum tree_code subcode = resultcode;
2676 tree int_type = TREE_TYPE (intop);
2677 if (TREE_CODE (intop) == MINUS_EXPR)
2678 subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
2679 /* Convert both subexpression types to the type of intop,
2680 because weird cases involving pointer arithmetic
2681 can result in a sum or difference with different type args. */
2682 ptrop = build_binary_op (subcode, ptrop,
2683 convert (int_type, TREE_OPERAND (intop, 1)), 1);
2684 intop = convert (int_type, TREE_OPERAND (intop, 0));
2687 /* Convert the integer argument to a type the same size as sizetype
2688 so the multiply won't overflow spuriously. */
2690 if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype)
2691 || TREE_UNSIGNED (TREE_TYPE (intop)) != TREE_UNSIGNED (sizetype))
2692 intop = convert (type_for_size (TYPE_PRECISION (sizetype),
2693 TREE_UNSIGNED (sizetype)), intop);
2695 /* Replace the integer argument with a suitable product by the object size.
2696 Do this multiplication as signed, then convert to the appropriate
2697 pointer type (actually unsigned integral). */
2699 intop = convert (result_type,
2700 build_binary_op (MULT_EXPR, intop,
2701 convert (TREE_TYPE (intop), size_exp), 1));
2703 /* Create the sum or difference. */
2705 result = build (resultcode, result_type, ptrop, intop);
2707 folded = fold (result);
2708 if (folded == result)
2709 TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop);
2713 /* Return a tree for the difference of pointers OP0 and OP1.
2714 The resulting tree has type int. */
2717 pointer_diff (op0, op1)
2718 register tree op0, op1;
2720 register tree result, folded;
2721 tree restype = ptrdiff_type_node;
2723 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2725 if (pedantic || warn_pointer_arith)
2727 if (TREE_CODE (target_type) == VOID_TYPE)
2728 pedwarn ("pointer of type `void *' used in subtraction");
2729 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2730 pedwarn ("pointer to a function used in subtraction");
2733 /* First do the subtraction as integers;
2734 then drop through to build the divide operator.
2735 Do not do default conversions on the minus operator
2736 in case restype is a short type. */
2738 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2739 convert (restype, op1), 0);
2740 /* This generates an error if op1 is pointer to incomplete type. */
2741 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
2742 error ("arithmetic on pointer to an incomplete type");
2744 /* This generates an error if op0 is pointer to incomplete type. */
2745 op1 = c_size_in_bytes (target_type);
2747 /* Divide by the size, in easiest possible way. */
2749 result = build (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2751 folded = fold (result);
2752 if (folded == result)
2753 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2757 /* Construct and perhaps optimize a tree representation
2758 for a unary operation. CODE, a tree_code, specifies the operation
2759 and XARG is the operand. NOCONVERT nonzero suppresses
2760 the default promotions (such as from short to int). */
2763 build_unary_op (code, xarg, noconvert)
2764 enum tree_code code;
2768 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2769 register tree arg = xarg;
2770 register tree argtype = 0;
2771 register enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2774 if (typecode == ERROR_MARK)
2775 return error_mark_node;
2776 if (typecode == ENUMERAL_TYPE)
2777 typecode = INTEGER_TYPE;
2782 /* This is used for unary plus, because a CONVERT_EXPR
2783 is enough to prevent anybody from looking inside for
2784 associativity, but won't generate any code. */
2785 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2786 || typecode == COMPLEX_TYPE))
2788 error ("wrong type argument to unary plus");
2789 return error_mark_node;
2791 else if (!noconvert)
2792 arg = default_conversion (arg);
2796 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2797 || typecode == COMPLEX_TYPE))
2799 error ("wrong type argument to unary minus");
2800 return error_mark_node;
2802 else if (!noconvert)
2803 arg = default_conversion (arg);
2807 if (typecode == COMPLEX_TYPE)
2811 pedwarn ("ISO C does not support `~' for complex conjugation");
2813 arg = default_conversion (arg);
2815 else if (typecode != INTEGER_TYPE)
2817 error ("wrong type argument to bit-complement");
2818 return error_mark_node;
2820 else if (!noconvert)
2821 arg = default_conversion (arg);
2825 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2826 || typecode == COMPLEX_TYPE))
2828 error ("wrong type argument to abs");
2829 return error_mark_node;
2831 else if (!noconvert)
2832 arg = default_conversion (arg);
2836 /* Conjugating a real value is a no-op, but allow it anyway. */
2837 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2838 || typecode == COMPLEX_TYPE))
2840 error ("wrong type argument to conjugation");
2841 return error_mark_node;
2843 else if (!noconvert)
2844 arg = default_conversion (arg);
2847 case TRUTH_NOT_EXPR:
2848 if (typecode != INTEGER_TYPE
2849 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2850 && typecode != COMPLEX_TYPE
2851 /* These will convert to a pointer. */
2852 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2854 error ("wrong type argument to unary exclamation mark");
2855 return error_mark_node;
2857 arg = truthvalue_conversion (arg);
2858 return invert_truthvalue (arg);
2864 if (TREE_CODE (arg) == COMPLEX_CST)
2865 return TREE_REALPART (arg);
2866 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2867 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2872 if (TREE_CODE (arg) == COMPLEX_CST)
2873 return TREE_IMAGPART (arg);
2874 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2875 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2877 return convert (TREE_TYPE (arg), integer_zero_node);
2879 case PREINCREMENT_EXPR:
2880 case POSTINCREMENT_EXPR:
2881 case PREDECREMENT_EXPR:
2882 case POSTDECREMENT_EXPR:
2883 /* Handle complex lvalues (when permitted)
2884 by reduction to simpler cases. */
2886 val = unary_complex_lvalue (code, arg);
2890 /* Increment or decrement the real part of the value,
2891 and don't change the imaginary part. */
2892 if (typecode == COMPLEX_TYPE)
2896 arg = stabilize_reference (arg);
2897 real = build_unary_op (REALPART_EXPR, arg, 1);
2898 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2899 return build (COMPLEX_EXPR, TREE_TYPE (arg),
2900 build_unary_op (code, real, 1), imag);
2903 /* Report invalid types. */
2905 if (typecode != POINTER_TYPE
2906 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2908 error ("wrong type argument to %s",
2909 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2910 ? "increment" : "decrement");
2911 return error_mark_node;
2916 tree result_type = TREE_TYPE (arg);
2918 arg = get_unwidened (arg, 0);
2919 argtype = TREE_TYPE (arg);
2921 /* Compute the increment. */
2923 if (typecode == POINTER_TYPE)
2925 /* If pointer target is an undefined struct,
2926 we just cannot know how to do the arithmetic. */
2927 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2928 error ("%s of pointer to unknown structure",
2929 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2930 ? "increment" : "decrement");
2931 else if ((pedantic || warn_pointer_arith)
2932 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2933 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2934 pedwarn ("wrong type argument to %s",
2935 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2936 ? "increment" : "decrement");
2937 inc = c_size_in_bytes (TREE_TYPE (result_type));
2940 inc = integer_one_node;
2942 inc = convert (argtype, inc);
2944 /* Handle incrementing a cast-expression. */
2947 switch (TREE_CODE (arg))
2952 case FIX_TRUNC_EXPR:
2953 case FIX_FLOOR_EXPR:
2954 case FIX_ROUND_EXPR:
2956 pedantic_lvalue_warning (CONVERT_EXPR);
2957 /* If the real type has the same machine representation
2958 as the type it is cast to, we can make better output
2959 by adding directly to the inside of the cast. */
2960 if ((TREE_CODE (TREE_TYPE (arg))
2961 == TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0))))
2962 && (TYPE_MODE (TREE_TYPE (arg))
2963 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (arg, 0)))))
2964 arg = TREE_OPERAND (arg, 0);
2967 tree incremented, modify, value;
2968 arg = stabilize_reference (arg);
2969 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
2972 value = save_expr (arg);
2973 incremented = build (((code == PREINCREMENT_EXPR
2974 || code == POSTINCREMENT_EXPR)
2975 ? PLUS_EXPR : MINUS_EXPR),
2976 argtype, value, inc);
2977 TREE_SIDE_EFFECTS (incremented) = 1;
2978 modify = build_modify_expr (arg, NOP_EXPR, incremented);
2979 value = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
2980 TREE_USED (value) = 1;
2990 /* Complain about anything else that is not a true lvalue. */
2991 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2992 || code == POSTINCREMENT_EXPR)
2993 ? "invalid lvalue in increment"
2994 : "invalid lvalue in decrement")))
2995 return error_mark_node;
2997 /* Report a read-only lvalue. */
2998 if (TREE_READONLY (arg))
2999 readonly_warning (arg,
3000 ((code == PREINCREMENT_EXPR
3001 || code == POSTINCREMENT_EXPR)
3002 ? "increment" : "decrement"));
3004 val = build (code, TREE_TYPE (arg), arg, inc);
3005 TREE_SIDE_EFFECTS (val) = 1;
3006 val = convert (result_type, val);
3007 if (TREE_CODE (val) != code)
3008 TREE_NO_UNUSED_WARNING (val) = 1;
3013 /* Note that this operation never does default_conversion
3014 regardless of NOCONVERT. */
3016 /* Let &* cancel out to simplify resulting code. */
3017 if (TREE_CODE (arg) == INDIRECT_REF)
3019 /* Don't let this be an lvalue. */
3020 if (lvalue_p (TREE_OPERAND (arg, 0)))
3021 return non_lvalue (TREE_OPERAND (arg, 0));
3022 return TREE_OPERAND (arg, 0);
3025 /* For &x[y], return x+y */
3026 if (TREE_CODE (arg) == ARRAY_REF)
3028 if (mark_addressable (TREE_OPERAND (arg, 0)) == 0)
3029 return error_mark_node;
3030 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
3031 TREE_OPERAND (arg, 1), 1);
3034 /* Handle complex lvalues (when permitted)
3035 by reduction to simpler cases. */
3036 val = unary_complex_lvalue (code, arg);
3040 #if 0 /* Turned off because inconsistent;
3041 float f; *&(int)f = 3.4 stores in int format
3042 whereas (int)f = 3.4 stores in float format. */
3043 /* Address of a cast is just a cast of the address
3044 of the operand of the cast. */
3045 switch (TREE_CODE (arg))
3050 case FIX_TRUNC_EXPR:
3051 case FIX_FLOOR_EXPR:
3052 case FIX_ROUND_EXPR:
3055 pedwarn ("ISO C forbids the address of a cast expression");
3056 return convert (build_pointer_type (TREE_TYPE (arg)),
3057 build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0),
3062 /* Allow the address of a constructor if all the elements
3064 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_CONSTANT (arg))
3066 /* Anything not already handled and not a true memory reference
3068 else if (typecode != FUNCTION_TYPE
3069 && !lvalue_or_else (arg, "invalid lvalue in unary `&'"))
3070 return error_mark_node;
3072 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3073 argtype = TREE_TYPE (arg);
3075 /* If the lvalue is const or volatile, merge that into the type
3076 to which the address will point. Note that you can't get a
3077 restricted pointer by taking the address of something, so we
3078 only have to deal with `const' and `volatile' here. */
3079 if ((DECL_P (arg) || TREE_CODE_CLASS (TREE_CODE (arg)) == 'r')
3080 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
3081 argtype = c_build_type_variant (argtype,
3082 TREE_READONLY (arg),
3083 TREE_THIS_VOLATILE (arg));
3085 argtype = build_pointer_type (argtype);
3087 if (mark_addressable (arg) == 0)
3088 return error_mark_node;
3093 if (TREE_CODE (arg) == COMPONENT_REF)
3095 tree field = TREE_OPERAND (arg, 1);
3097 addr = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
3099 if (DECL_C_BIT_FIELD (field))
3101 error ("attempt to take address of bit-field structure member `%s'",
3102 IDENTIFIER_POINTER (DECL_NAME (field)));
3103 return error_mark_node;
3106 addr = fold (build (PLUS_EXPR, argtype,
3107 convert (argtype, addr),
3108 convert (argtype, byte_position (field))));
3111 addr = build1 (code, argtype, arg);
3113 /* Address of a static or external variable or
3114 file-scope function counts as a constant. */
3116 && ! (TREE_CODE (arg) == FUNCTION_DECL
3117 && DECL_CONTEXT (arg) != 0))
3118 TREE_CONSTANT (addr) = 1;
3127 argtype = TREE_TYPE (arg);
3128 return fold (build1 (code, argtype, arg));
3132 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3133 convert ARG with the same conversions in the same order
3134 and return the result. */
3137 convert_sequence (conversions, arg)
3141 switch (TREE_CODE (conversions))
3146 case FIX_TRUNC_EXPR:
3147 case FIX_FLOOR_EXPR:
3148 case FIX_ROUND_EXPR:
3150 return convert (TREE_TYPE (conversions),
3151 convert_sequence (TREE_OPERAND (conversions, 0),
3160 /* Return nonzero if REF is an lvalue valid for this language.
3161 Lvalues can be assigned, unless their type has TYPE_READONLY.
3162 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3168 register enum tree_code code = TREE_CODE (ref);
3175 return lvalue_p (TREE_OPERAND (ref, 0));
3186 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3187 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3191 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3198 /* Return nonzero if REF is an lvalue valid for this language;
3199 otherwise, print an error message and return zero. */
3202 lvalue_or_else (ref, msgid)
3206 int win = lvalue_p (ref);
3209 error ("%s", msgid);
3214 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3215 for certain kinds of expressions which are not really lvalues
3216 but which we can accept as lvalues.
3218 If ARG is not a kind of expression we can handle, return zero. */
3221 unary_complex_lvalue (code, arg)
3222 enum tree_code code;
3225 /* Handle (a, b) used as an "lvalue". */
3226 if (TREE_CODE (arg) == COMPOUND_EXPR)
3228 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
3230 /* If this returns a function type, it isn't really being used as
3231 an lvalue, so don't issue a warning about it. */
3232 if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE)
3233 pedantic_lvalue_warning (COMPOUND_EXPR);
3235 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
3236 TREE_OPERAND (arg, 0), real_result);
3239 /* Handle (a ? b : c) used as an "lvalue". */
3240 if (TREE_CODE (arg) == COND_EXPR)
3242 pedantic_lvalue_warning (COND_EXPR);
3243 if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE)
3244 pedantic_lvalue_warning (COMPOUND_EXPR);
3246 return (build_conditional_expr
3247 (TREE_OPERAND (arg, 0),
3248 build_unary_op (code, TREE_OPERAND (arg, 1), 0),
3249 build_unary_op (code, TREE_OPERAND (arg, 2), 0)));
3255 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3256 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3259 pedantic_lvalue_warning (code)
3260 enum tree_code code;
3266 pedwarn ("ISO C forbids use of conditional expressions as lvalues");
3269 pedwarn ("ISO C forbids use of compound expressions as lvalues");
3272 pedwarn ("ISO C forbids use of cast expressions as lvalues");
3277 /* Warn about storing in something that is `const'. */
3280 readonly_warning (arg, msgid)
3284 if (TREE_CODE (arg) == COMPONENT_REF)
3286 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3287 readonly_warning (TREE_OPERAND (arg, 0), msgid);
3289 pedwarn ("%s of read-only member `%s'", _(msgid),
3290 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1))));
3292 else if (TREE_CODE (arg) == VAR_DECL)
3293 pedwarn ("%s of read-only variable `%s'", _(msgid),
3294 IDENTIFIER_POINTER (DECL_NAME (arg)));
3296 pedwarn ("%s of read-only location", _(msgid));
3299 /* Mark EXP saying that we need to be able to take the
3300 address of it; it should not be allocated in a register.
3301 Value is 1 if successful. */
3304 mark_addressable (exp)
3307 register tree x = exp;
3309 switch (TREE_CODE (x))
3312 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3314 error ("cannot take address of bitfield `%s'",
3315 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (x, 1))));
3319 /* ... fall through ... */
3325 x = TREE_OPERAND (x, 0);
3329 TREE_ADDRESSABLE (x) = 1;
3336 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
3337 && DECL_NONLOCAL (x))
3339 if (TREE_PUBLIC (x))
3341 error ("global register variable `%s' used in nested function",
3342 IDENTIFIER_POINTER (DECL_NAME (x)));
3345 pedwarn ("register variable `%s' used in nested function",
3346 IDENTIFIER_POINTER (DECL_NAME (x)));
3348 else if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x))
3350 if (TREE_PUBLIC (x))
3352 error ("address of global register variable `%s' requested",
3353 IDENTIFIER_POINTER (DECL_NAME (x)));
3357 /* If we are making this addressable due to its having
3358 volatile components, give a different error message. Also
3359 handle the case of an unnamed parameter by not trying
3360 to give the name. */
3362 else if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (x)))
3364 error ("cannot put object with volatile field into register");
3368 pedwarn ("address of register variable `%s' requested",
3369 IDENTIFIER_POINTER (DECL_NAME (x)));
3371 put_var_into_stack (x);
3375 TREE_ADDRESSABLE (x) = 1;
3376 #if 0 /* poplevel deals with this now. */
3377 if (DECL_CONTEXT (x) == 0)
3378 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
3386 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3389 build_conditional_expr (ifexp, op1, op2)
3390 tree ifexp, op1, op2;
3392 register tree type1;
3393 register tree type2;
3394 register enum tree_code code1;
3395 register enum tree_code code2;
3396 register tree result_type = NULL;
3397 tree orig_op1 = op1, orig_op2 = op2;
3399 ifexp = truthvalue_conversion (default_conversion (ifexp));
3401 #if 0 /* Produces wrong result if within sizeof. */
3402 /* Don't promote the operands separately if they promote
3403 the same way. Return the unpromoted type and let the combined
3404 value get promoted if necessary. */
3406 if (TREE_TYPE (op1) == TREE_TYPE (op2)
3407 && TREE_CODE (TREE_TYPE (op1)) != ARRAY_TYPE
3408 && TREE_CODE (TREE_TYPE (op1)) != ENUMERAL_TYPE
3409 && TREE_CODE (TREE_TYPE (op1)) != FUNCTION_TYPE)
3411 if (TREE_CODE (ifexp) == INTEGER_CST)
3412 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3414 return fold (build (COND_EXPR, TREE_TYPE (op1), ifexp, op1, op2));
3418 /* Promote both alternatives. */
3420 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3421 op1 = default_conversion (op1);
3422 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3423 op2 = default_conversion (op2);
3425 if (TREE_CODE (ifexp) == ERROR_MARK
3426 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3427 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3428 return error_mark_node;
3430 type1 = TREE_TYPE (op1);
3431 code1 = TREE_CODE (type1);
3432 type2 = TREE_TYPE (op2);
3433 code2 = TREE_CODE (type2);
3435 /* Quickly detect the usual case where op1 and op2 have the same type
3437 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3440 result_type = type1;
3442 result_type = TYPE_MAIN_VARIANT (type1);
3444 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3445 || code1 == COMPLEX_TYPE)
3446 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3447 || code2 == COMPLEX_TYPE))
3449 result_type = common_type (type1, type2);
3451 /* If -Wsign-compare, warn here if type1 and type2 have
3452 different signedness. We'll promote the signed to unsigned
3453 and later code won't know it used to be different.
3454 Do this check on the original types, so that explicit casts
3455 will be considered, but default promotions won't. */
3456 if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare)
3457 && !skip_evaluation)
3459 int unsigned_op1 = TREE_UNSIGNED (TREE_TYPE (orig_op1));
3460 int unsigned_op2 = TREE_UNSIGNED (TREE_TYPE (orig_op2));
3462 if (unsigned_op1 ^ unsigned_op2)
3464 /* Do not warn if the result type is signed, since the
3465 signed type will only be chosen if it can represent
3466 all the values of the unsigned type. */
3467 if (! TREE_UNSIGNED (result_type))
3469 /* Do not warn if the signed quantity is an unsuffixed
3470 integer literal (or some static constant expression
3471 involving such literals) and it is non-negative. */
3472 else if ((unsigned_op2 && tree_expr_nonnegative_p (op1))
3473 || (unsigned_op1 && tree_expr_nonnegative_p (op2)))
3476 warning ("signed and unsigned type in conditional expression");
3480 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3482 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3483 pedwarn ("ISO C forbids conditional expr with only one void side");
3484 result_type = void_type_node;
3486 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3488 if (comp_target_types (type1, type2))
3489 result_type = common_type (type1, type2);
3490 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
3491 && TREE_CODE (orig_op1) != NOP_EXPR)
3492 result_type = qualify_type (type2, type1);
3493 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
3494 && TREE_CODE (orig_op2) != NOP_EXPR)
3495 result_type = qualify_type (type1, type2);
3496 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3498 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3499 pedwarn ("ISO C forbids conditional expr between `void *' and function pointer");
3500 result_type = qualify_type (type1, type2);
3502 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3504 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3505 pedwarn ("ISO C forbids conditional expr between `void *' and function pointer");
3506 result_type = qualify_type (type2, type1);
3510 pedwarn ("pointer type mismatch in conditional expression");
3511 result_type = build_pointer_type (void_type_node);
3514 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3516 if (! integer_zerop (op2))
3517 pedwarn ("pointer/integer type mismatch in conditional expression");
3520 op2 = null_pointer_node;
3521 #if 0 /* The spec seems to say this is permitted. */
3522 if (pedantic && TREE_CODE (type1) == FUNCTION_TYPE)
3523 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3526 result_type = type1;
3528 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3530 if (!integer_zerop (op1))
3531 pedwarn ("pointer/integer type mismatch in conditional expression");
3534 op1 = null_pointer_node;
3535 #if 0 /* The spec seems to say this is permitted. */
3536 if (pedantic && TREE_CODE (type2) == FUNCTION_TYPE)
3537 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3540 result_type = type2;
3545 if (flag_cond_mismatch)
3546 result_type = void_type_node;
3549 error ("type mismatch in conditional expression");
3550 return error_mark_node;
3554 /* Merge const and volatile flags of the incoming types. */
3556 = build_type_variant (result_type,
3557 TREE_READONLY (op1) || TREE_READONLY (op2),
3558 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3560 if (result_type != TREE_TYPE (op1))
3561 op1 = convert_and_check (result_type, op1);
3562 if (result_type != TREE_TYPE (op2))
3563 op2 = convert_and_check (result_type, op2);
3565 if (TREE_CODE (ifexp) == INTEGER_CST)
3566 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3568 return fold (build (COND_EXPR, result_type, ifexp, op1, op2));
3571 /* Given a list of expressions, return a compound expression
3572 that performs them all and returns the value of the last of them. */
3575 build_compound_expr (list)
3578 return internal_build_compound_expr (list, TRUE);
3582 internal_build_compound_expr (list, first_p)
3588 if (TREE_CHAIN (list) == 0)
3590 #if 0 /* If something inside inhibited lvalueness, we should not override. */
3591 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3593 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3594 if (TREE_CODE (list) == NON_LVALUE_EXPR)
3595 list = TREE_OPERAND (list, 0);
3598 /* Don't let (0, 0) be null pointer constant. */
3599 if (!first_p && integer_zerop (TREE_VALUE (list)))
3600 return non_lvalue (TREE_VALUE (list));
3601 return TREE_VALUE (list);
3604 if (TREE_CHAIN (list) != 0 && TREE_CHAIN (TREE_CHAIN (list)) == 0)
3606 /* Convert arrays to pointers when there really is a comma operator. */
3607 if (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (list)))) == ARRAY_TYPE)
3608 TREE_VALUE (TREE_CHAIN (list))
3609 = default_conversion (TREE_VALUE (TREE_CHAIN (list)));
3612 rest = internal_build_compound_expr (TREE_CHAIN (list), FALSE);
3614 if (! TREE_SIDE_EFFECTS (TREE_VALUE (list)))
3616 /* The left-hand operand of a comma expression is like an expression
3617 statement: with -W or -Wunused, we should warn if it doesn't have
3618 any side-effects, unless it was explicitly cast to (void). */
3619 if ((extra_warnings || warn_unused_value)
3620 && ! (TREE_CODE (TREE_VALUE (list)) == CONVERT_EXPR
3621 && VOID_TYPE_P (TREE_TYPE (TREE_VALUE (list)))))
3622 warning ("left-hand operand of comma expression has no effect");
3624 /* When pedantic, a compound expression can be neither an lvalue
3625 nor an integer constant expression. */
3630 /* With -Wunused, we should also warn if the left-hand operand does have
3631 side-effects, but computes a value which is not used. For example, in
3632 `foo() + bar(), baz()' the result of the `+' operator is not used,
3633 so we should issue a warning. */
3634 else if (warn_unused_value)
3635 warn_if_unused_value (TREE_VALUE (list));
3637 return build (COMPOUND_EXPR, TREE_TYPE (rest), TREE_VALUE (list), rest);
3640 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3643 build_c_cast (type, expr)
3647 register tree value = expr;
3649 if (type == error_mark_node || expr == error_mark_node)
3650 return error_mark_node;
3651 type = TYPE_MAIN_VARIANT (type);
3654 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3655 if (TREE_CODE (value) == NON_LVALUE_EXPR)
3656 value = TREE_OPERAND (value, 0);
3659 if (TREE_CODE (type) == ARRAY_TYPE)
3661 error ("cast specifies array type");
3662 return error_mark_node;
3665 if (TREE_CODE (type) == FUNCTION_TYPE)
3667 error ("cast specifies function type");
3668 return error_mark_node;
3671 if (type == TREE_TYPE (value))
3675 if (TREE_CODE (type) == RECORD_TYPE
3676 || TREE_CODE (type) == UNION_TYPE)
3677 pedwarn ("ISO C forbids casting nonscalar to the same type");
3680 else if (TREE_CODE (type) == UNION_TYPE)
3683 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
3684 || TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE)
3685 value = default_conversion (value);
3687 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3688 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3689 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3698 pedwarn ("ISO C forbids casts to union type");
3699 if (TYPE_NAME (type) != 0)
3701 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
3702 name = IDENTIFIER_POINTER (TYPE_NAME (type));
3704 name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));
3708 t = digest_init (type, build (CONSTRUCTOR, type, NULL_TREE,
3709 build_tree_list (field, value)),
3711 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3714 error ("cast to union type from type not present in union");
3715 return error_mark_node;
3721 /* If casting to void, avoid the error that would come
3722 from default_conversion in the case of a non-lvalue array. */
3723 if (type == void_type_node)
3724 return build1 (CONVERT_EXPR, type, value);
3726 /* Convert functions and arrays to pointers,
3727 but don't convert any other types. */
3728 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
3729 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE)
3730 value = default_conversion (value);
3731 otype = TREE_TYPE (value);
3733 /* Optionally warn about potentially worrisome casts. */
3736 && TREE_CODE (type) == POINTER_TYPE
3737 && TREE_CODE (otype) == POINTER_TYPE)
3739 tree in_type = type;
3740 tree in_otype = otype;
3743 /* Check that the qualifiers on IN_TYPE are a superset of
3744 the qualifiers of IN_OTYPE. The outermost level of
3745 POINTER_TYPE nodes is uninteresting and we stop as soon
3746 as we hit a non-POINTER_TYPE node on either type. */
3749 in_otype = TREE_TYPE (in_otype);
3750 in_type = TREE_TYPE (in_type);
3751 warn |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3753 while (TREE_CODE (in_type) == POINTER_TYPE
3754 && TREE_CODE (in_otype) == POINTER_TYPE);
3757 /* There are qualifiers present in IN_OTYPE that are not
3758 present in IN_TYPE. */
3759 warning ("cast discards qualifiers from pointer target type");
3762 /* Warn about possible alignment problems. */
3763 if (STRICT_ALIGNMENT && warn_cast_align
3764 && TREE_CODE (type) == POINTER_TYPE
3765 && TREE_CODE (otype) == POINTER_TYPE
3766 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3767 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3768 /* Don't warn about opaque types, where the actual alignment
3769 restriction is unknown. */
3770 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3771 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3772 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3773 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3774 warning ("cast increases required alignment of target type");
3776 if (TREE_CODE (type) == INTEGER_TYPE
3777 && TREE_CODE (otype) == POINTER_TYPE
3778 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3779 && !TREE_CONSTANT (value))
3780 warning ("cast from pointer to integer of different size");
3782 if (warn_bad_function_cast
3783 && TREE_CODE (value) == CALL_EXPR
3784 && TREE_CODE (type) != TREE_CODE (otype))
3785 warning ("cast does not match function type");
3787 if (TREE_CODE (type) == POINTER_TYPE
3788 && TREE_CODE (otype) == INTEGER_TYPE
3789 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3790 /* Don't warn about converting any constant. */
3791 && !TREE_CONSTANT (value))
3792 warning ("cast to pointer from integer of different size");
3795 value = convert (type, value);
3797 /* Ignore any integer overflow caused by the cast. */
3798 if (TREE_CODE (value) == INTEGER_CST)
3800 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3801 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3805 /* Pedantically, don't ley (void *) (FOO *) 0 be a null pointer constant. */
3806 if (pedantic && TREE_CODE (value) == INTEGER_CST
3807 && TREE_CODE (expr) == INTEGER_CST
3808 && TREE_CODE (TREE_TYPE (expr)) != INTEGER_TYPE)
3809 value = non_lvalue (value);
3811 /* If pedantic, don't let a cast be an lvalue. */
3812 if (value == expr && pedantic)
3813 value = non_lvalue (value);
3818 /* Build an assignment expression of lvalue LHS from value RHS.
3819 MODIFYCODE is the code for a binary operator that we use
3820 to combine the old value of LHS with RHS to get the new value.
3821 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3824 build_modify_expr (lhs, modifycode, rhs)
3826 enum tree_code modifycode;
3828 register tree result;
3830 tree lhstype = TREE_TYPE (lhs);
3831 tree olhstype = lhstype;
3833 /* Types that aren't fully specified cannot be used in assignments. */
3834 lhs = require_complete_type (lhs);
3836 /* Avoid duplicate error messages from operands that had errors. */
3837 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3838 return error_mark_node;
3840 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3841 /* Do not use STRIP_NOPS here. We do not want an enumerator
3842 whose value is 0 to count as a null pointer constant. */
3843 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3844 rhs = TREE_OPERAND (rhs, 0);
3848 /* Handle control structure constructs used as "lvalues". */
3850 switch (TREE_CODE (lhs))
3852 /* Handle (a, b) used as an "lvalue". */
3854 pedantic_lvalue_warning (COMPOUND_EXPR);
3855 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1), modifycode, rhs);
3856 if (TREE_CODE (newrhs) == ERROR_MARK)
3857 return error_mark_node;
3858 return build (COMPOUND_EXPR, lhstype,
3859 TREE_OPERAND (lhs, 0), newrhs);
3861 /* Handle (a ? b : c) used as an "lvalue". */
3863 pedantic_lvalue_warning (COND_EXPR);
3864 rhs = save_expr (rhs);
3866 /* Produce (a ? (b = rhs) : (c = rhs))
3867 except that the RHS goes through a save-expr
3868 so the code to compute it is only emitted once. */
3870 = build_conditional_expr (TREE_OPERAND (lhs, 0),
3871 build_modify_expr (TREE_OPERAND (lhs, 1),
3873 build_modify_expr (TREE_OPERAND (lhs, 2),
3875 if (TREE_CODE (cond) == ERROR_MARK)
3877 /* Make sure the code to compute the rhs comes out
3878 before the split. */
3879 return build (COMPOUND_EXPR, TREE_TYPE (lhs),
3880 /* But cast it to void to avoid an "unused" error. */
3881 convert (void_type_node, rhs), cond);
3887 /* If a binary op has been requested, combine the old LHS value with the RHS
3888 producing the value we should actually store into the LHS. */
3890 if (modifycode != NOP_EXPR)
3892 lhs = stabilize_reference (lhs);
3893 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3896 /* Handle a cast used as an "lvalue".
3897 We have already performed any binary operator using the value as cast.
3898 Now convert the result to the cast type of the lhs,
3899 and then true type of the lhs and store it there;
3900 then convert result back to the cast type to be the value
3901 of the assignment. */
3903 switch (TREE_CODE (lhs))
3908 case FIX_TRUNC_EXPR:
3909 case FIX_FLOOR_EXPR:
3910 case FIX_ROUND_EXPR:
3912 if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
3913 || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE)
3914 newrhs = default_conversion (newrhs);
3916 tree inner_lhs = TREE_OPERAND (lhs, 0);
3918 result = build_modify_expr (inner_lhs, NOP_EXPR,
3919 convert (TREE_TYPE (inner_lhs),
3920 convert (lhstype, newrhs)));
3921 if (TREE_CODE (result) == ERROR_MARK)
3923 pedantic_lvalue_warning (CONVERT_EXPR);
3924 return convert (TREE_TYPE (lhs), result);
3931 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3932 Reject anything strange now. */
3934 if (!lvalue_or_else (lhs, "invalid lvalue in assignment"))
3935 return error_mark_node;
3937 /* Warn about storing in something that is `const'. */
3939 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3940 || ((TREE_CODE (lhstype) == RECORD_TYPE
3941 || TREE_CODE (lhstype) == UNION_TYPE)
3942 && C_TYPE_FIELDS_READONLY (lhstype)))
3943 readonly_warning (lhs, "assignment");
3945 /* If storing into a structure or union member,
3946 it has probably been given type `int'.
3947 Compute the type that would go with
3948 the actual amount of storage the member occupies. */
3950 if (TREE_CODE (lhs) == COMPONENT_REF
3951 && (TREE_CODE (lhstype) == INTEGER_TYPE
3952 || TREE_CODE (lhstype) == REAL_TYPE
3953 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3954 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3956 /* If storing in a field that is in actuality a short or narrower than one,
3957 we must store in the field in its actual type. */
3959 if (lhstype != TREE_TYPE (lhs))
3961 lhs = copy_node (lhs);
3962 TREE_TYPE (lhs) = lhstype;
3965 /* Convert new value to destination type. */
3967 newrhs = convert_for_assignment (lhstype, newrhs, _("assignment"),
3968 NULL_TREE, NULL_TREE, 0);
3969 if (TREE_CODE (newrhs) == ERROR_MARK)
3970 return error_mark_node;
3972 result = build (MODIFY_EXPR, lhstype, lhs, newrhs);
3973 TREE_SIDE_EFFECTS (result) = 1;
3975 /* If we got the LHS in a different type for storing in,
3976 convert the result back to the nominal type of LHS
3977 so that the value we return always has the same type
3978 as the LHS argument. */
3980 if (olhstype == TREE_TYPE (result))
3982 return convert_for_assignment (olhstype, result, _("assignment"),
3983 NULL_TREE, NULL_TREE, 0);
3986 /* Convert value RHS to type TYPE as preparation for an assignment
3987 to an lvalue of type TYPE.
3988 The real work of conversion is done by `convert'.
3989 The purpose of this function is to generate error messages
3990 for assignments that are not allowed in C.
3991 ERRTYPE is a string to use in error messages:
3992 "assignment", "return", etc. If it is null, this is parameter passing
3993 for a function call (and different error messages are output).
3995 FUNNAME is the name of the function being called,
3996 as an IDENTIFIER_NODE, or null.
3997 PARMNUM is the number of the argument, for printing in error messages. */
4000 convert_for_assignment (type, rhs, errtype, fundecl, funname, parmnum)
4002 const char *errtype;
4003 tree fundecl, funname;
4006 register enum tree_code codel = TREE_CODE (type);
4007 register tree rhstype;
4008 register enum tree_code coder;
4010 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4011 /* Do not use STRIP_NOPS here. We do not want an enumerator
4012 whose value is 0 to count as a null pointer constant. */
4013 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
4014 rhs = TREE_OPERAND (rhs, 0);
4016 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
4017 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
4018 rhs = default_conversion (rhs);
4019 else if (optimize && TREE_CODE (rhs) == VAR_DECL)
4020 rhs = decl_constant_value (rhs);
4022 rhstype = TREE_TYPE (rhs);
4023 coder = TREE_CODE (rhstype);
4025 if (coder == ERROR_MARK)
4026 return error_mark_node;
4028 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
4030 overflow_warning (rhs);
4031 /* Check for Objective-C protocols. This will issue a warning if
4032 there are protocol violations. No need to use the return value. */
4033 maybe_objc_comptypes (type, rhstype, 0);
4037 if (coder == VOID_TYPE)
4039 error ("void value not ignored as it ought to be");
4040 return error_mark_node;
4042 /* A type converts to a reference to it.
4043 This code doesn't fully support references, it's just for the
4044 special case of va_start and va_copy. */
4045 if (codel == REFERENCE_TYPE
4046 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
4048 if (mark_addressable (rhs) == 0)
4049 return error_mark_node;
4050 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
4052 /* We already know that these two types are compatible, but they
4053 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4054 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4055 likely to be va_list, a typedef to __builtin_va_list, which
4056 is different enough that it will cause problems later. */
4057 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
4058 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
4060 rhs = build1 (NOP_EXPR, type, rhs);
4063 /* Arithmetic types all interconvert, and enum is treated like int. */
4064 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
4065 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE)
4066 && (coder == INTEGER_TYPE || coder == REAL_TYPE
4067 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE))
4068 return convert_and_check (type, rhs);
4070 /* Conversion to a transparent union from its member types.
4071 This applies only to function arguments. */
4072 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type) && ! errtype)
4075 tree marginal_memb_type = 0;
4077 for (memb_types = TYPE_FIELDS (type); memb_types;
4078 memb_types = TREE_CHAIN (memb_types))
4080 tree memb_type = TREE_TYPE (memb_types);
4082 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
4083 TYPE_MAIN_VARIANT (rhstype)))
4086 if (TREE_CODE (memb_type) != POINTER_TYPE)
4089 if (coder == POINTER_TYPE)
4091 register tree ttl = TREE_TYPE (memb_type);
4092 register tree ttr = TREE_TYPE (rhstype);
4094 /* Any non-function converts to a [const][volatile] void *
4095 and vice versa; otherwise, targets must be the same.
4096 Meanwhile, the lhs target must have all the qualifiers of
4098 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4099 || comp_target_types (memb_type, rhstype))
4101 /* If this type won't generate any warnings, use it. */
4102 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
4103 || ((TREE_CODE (ttr) == FUNCTION_TYPE
4104 && TREE_CODE (ttl) == FUNCTION_TYPE)
4105 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
4106 == TYPE_QUALS (ttr))
4107 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
4108 == TYPE_QUALS (ttl))))
4111 /* Keep looking for a better type, but remember this one. */
4112 if (! marginal_memb_type)
4113 marginal_memb_type = memb_type;
4117 /* Can convert integer zero to any pointer type. */
4118 if (integer_zerop (rhs)
4119 || (TREE_CODE (rhs) == NOP_EXPR
4120 && integer_zerop (TREE_OPERAND (rhs, 0))))
4122 rhs = null_pointer_node;
4127 if (memb_types || marginal_memb_type)
4131 /* We have only a marginally acceptable member type;
4132 it needs a warning. */
4133 register tree ttl = TREE_TYPE (marginal_memb_type);
4134 register tree ttr = TREE_TYPE (rhstype);
4136 /* Const and volatile mean something different for function
4137 types, so the usual warnings are not appropriate. */
4138 if (TREE_CODE (ttr) == FUNCTION_TYPE
4139 && TREE_CODE (ttl) == FUNCTION_TYPE)
4141 /* Because const and volatile on functions are
4142 restrictions that say the function will not do
4143 certain things, it is okay to use a const or volatile
4144 function where an ordinary one is wanted, but not
4146 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4147 warn_for_assignment ("%s makes qualified function pointer from unqualified",
4148 errtype, funname, parmnum);
4150 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4151 warn_for_assignment ("%s discards qualifiers from pointer target type",
4156 if (pedantic && ! DECL_IN_SYSTEM_HEADER (fundecl))
4157 pedwarn ("ISO C prohibits argument conversion to union type");
4159 return build1 (NOP_EXPR, type, rhs);
4163 /* Conversions among pointers */
4164 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
4165 && (coder == POINTER_TYPE || coder == REFERENCE_TYPE))
4167 register tree ttl = TREE_TYPE (type);
4168 register tree ttr = TREE_TYPE (rhstype);
4170 /* Any non-function converts to a [const][volatile] void *
4171 and vice versa; otherwise, targets must be the same.
4172 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4173 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4174 || comp_target_types (type, rhstype)
4175 || (unsigned_type (TYPE_MAIN_VARIANT (ttl))
4176 == unsigned_type (TYPE_MAIN_VARIANT (ttr))))
4179 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
4182 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4183 which are not ANSI null ptr constants. */
4184 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
4185 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4186 warn_for_assignment ("ISO C forbids %s between function pointer and `void *'",
4187 errtype, funname, parmnum);
4188 /* Const and volatile mean something different for function types,
4189 so the usual warnings are not appropriate. */
4190 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4191 && TREE_CODE (ttl) != FUNCTION_TYPE)
4193 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4194 warn_for_assignment ("%s discards qualifiers from pointer target type",
4195 errtype, funname, parmnum);
4196 /* If this is not a case of ignoring a mismatch in signedness,
4198 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4199 || comp_target_types (type, rhstype))
4201 /* If there is a mismatch, do warn. */
4203 warn_for_assignment ("pointer targets in %s differ in signedness",
4204 errtype, funname, parmnum);
4206 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4207 && TREE_CODE (ttr) == FUNCTION_TYPE)
4209 /* Because const and volatile on functions are restrictions
4210 that say the function will not do certain things,
4211 it is okay to use a const or volatile function
4212 where an ordinary one is wanted, but not vice-versa. */
4213 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4214 warn_for_assignment ("%s makes qualified function pointer from unqualified",
4215 errtype, funname, parmnum);
4219 warn_for_assignment ("%s from incompatible pointer type",
4220 errtype, funname, parmnum);
4221 return convert (type, rhs);
4223 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4225 /* An explicit constant 0 can convert to a pointer,
4226 or one that results from arithmetic, even including
4227 a cast to integer type. */
4228 if (! (TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
4230 ! (TREE_CODE (rhs) == NOP_EXPR
4231 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
4232 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
4233 && integer_zerop (TREE_OPERAND (rhs, 0))))
4235 warn_for_assignment ("%s makes pointer from integer without a cast",
4236 errtype, funname, parmnum);
4237 return convert (type, rhs);
4239 return null_pointer_node;
4241 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4243 warn_for_assignment ("%s makes integer from pointer without a cast",
4244 errtype, funname, parmnum);
4245 return convert (type, rhs);
4252 tree selector = maybe_building_objc_message_expr ();
4254 if (selector && parmnum > 2)
4255 error ("incompatible type for argument %d of `%s'",
4256 parmnum - 2, IDENTIFIER_POINTER (selector));
4258 error ("incompatible type for argument %d of `%s'",
4259 parmnum, IDENTIFIER_POINTER (funname));
4262 error ("incompatible type for argument %d of indirect function call",
4266 error ("incompatible types in %s", errtype);
4268 return error_mark_node;
4271 /* Print a warning using MSGID.
4272 It gets OPNAME as its one parameter.
4273 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4274 FUNCTION and ARGNUM are handled specially if we are building an
4275 Objective-C selector. */
4278 warn_for_assignment (msgid, opname, function, argnum)
4286 tree selector = maybe_building_objc_message_expr ();
4289 if (selector && argnum > 2)
4291 function = selector;
4296 /* Function name is known; supply it. */
4297 const char *argstring = _("passing arg %d of `%s'");
4298 new_opname = (char *) alloca (IDENTIFIER_LENGTH (function)
4299 + strlen (argstring) + 1 + 25
4301 sprintf (new_opname, argstring, argnum,
4302 IDENTIFIER_POINTER (function));
4306 /* Function name unknown (call through ptr); just give arg number.*/
4307 const char *argnofun = _("passing arg %d of pointer to function");
4308 new_opname = (char *) alloca (strlen (argnofun) + 1 + 25 /*%d*/ + 1);
4309 sprintf (new_opname, argnofun, argnum);
4311 opname = new_opname;
4313 pedwarn (msgid, opname);
4316 /* If VALUE is a compound expr all of whose expressions are constant, then
4317 return its value. Otherwise, return error_mark_node.
4319 This is for handling COMPOUND_EXPRs as initializer elements
4320 which is allowed with a warning when -pedantic is specified. */
4323 valid_compound_expr_initializer (value, endtype)
4327 if (TREE_CODE (value) == COMPOUND_EXPR)
4329 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4331 return error_mark_node;
4332 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4335 else if (! TREE_CONSTANT (value)
4336 && ! initializer_constant_valid_p (value, endtype))
4337 return error_mark_node;
4342 /* Perform appropriate conversions on the initial value of a variable,
4343 store it in the declaration DECL,
4344 and print any error messages that are appropriate.
4345 If the init is invalid, store an ERROR_MARK. */
4348 store_init_value (decl, init)
4351 register tree value, type;
4353 /* If variable's type was invalidly declared, just ignore it. */
4355 type = TREE_TYPE (decl);
4356 if (TREE_CODE (type) == ERROR_MARK)
4359 /* Digest the specified initializer into an expression. */
4361 value = digest_init (type, init, TREE_STATIC (decl),
4362 TREE_STATIC (decl) || pedantic);
4364 /* Store the expression if valid; else report error. */
4367 /* Note that this is the only place we can detect the error
4368 in a case such as struct foo bar = (struct foo) { x, y };
4369 where there is one initial value which is a constructor expression. */
4370 if (value == error_mark_node)
4372 else if (TREE_STATIC (decl) && ! TREE_CONSTANT (value))
4374 error ("initializer for static variable is not constant");
4375 value = error_mark_node;
4377 else if (TREE_STATIC (decl)
4378 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
4380 error ("initializer for static variable uses complicated arithmetic");
4381 value = error_mark_node;
4385 if (pedantic && TREE_CODE (value) == CONSTRUCTOR)
4387 if (! TREE_CONSTANT (value))
4388 pedwarn ("aggregate initializer is not constant");
4389 else if (! TREE_STATIC (value))
4390 pedwarn ("aggregate initializer uses complicated arithmetic");
4395 if (warn_traditional && !in_system_header
4396 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && ! TREE_STATIC (decl))
4397 warning ("traditional C rejects automatic aggregate initialization");
4399 DECL_INITIAL (decl) = value;
4401 /* ANSI wants warnings about out-of-range constant initializers. */
4402 STRIP_TYPE_NOPS (value);
4403 constant_expression_warning (value);
4406 /* Methods for storing and printing names for error messages. */
4408 /* Implement a spelling stack that allows components of a name to be pushed
4409 and popped. Each element on the stack is this structure. */
4421 #define SPELLING_STRING 1
4422 #define SPELLING_MEMBER 2
4423 #define SPELLING_BOUNDS 3
4425 static struct spelling *spelling; /* Next stack element (unused). */
4426 static struct spelling *spelling_base; /* Spelling stack base. */
4427 static int spelling_size; /* Size of the spelling stack. */
4429 /* Macros to save and restore the spelling stack around push_... functions.
4430 Alternative to SAVE_SPELLING_STACK. */
4432 #define SPELLING_DEPTH() (spelling - spelling_base)
4433 #define RESTORE_SPELLING_DEPTH(depth) (spelling = spelling_base + depth)
4435 /* Save and restore the spelling stack around arbitrary C code. */
4437 #define SAVE_SPELLING_DEPTH(code) \
4439 int __depth = SPELLING_DEPTH (); \
4441 RESTORE_SPELLING_DEPTH (__depth); \
4444 /* Push an element on the spelling stack with type KIND and assign VALUE
4447 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4449 int depth = SPELLING_DEPTH (); \
4451 if (depth >= spelling_size) \
4453 spelling_size += 10; \
4454 if (spelling_base == 0) \
4456 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4459 = (struct spelling *) xrealloc (spelling_base, \
4460 spelling_size * sizeof (struct spelling)); \
4461 RESTORE_SPELLING_DEPTH (depth); \
4464 spelling->kind = (KIND); \
4465 spelling->MEMBER = (VALUE); \
4469 /* Push STRING on the stack. Printed literally. */
4472 push_string (string)
4475 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4478 /* Push a member name on the stack. Printed as '.' STRING. */
4481 push_member_name (decl)
4486 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4487 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4490 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4493 push_array_bounds (bounds)
4496 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4499 /* Compute the maximum size in bytes of the printed spelling. */
4504 register int size = 0;
4505 register struct spelling *p;
4507 for (p = spelling_base; p < spelling; p++)
4509 if (p->kind == SPELLING_BOUNDS)
4512 size += strlen (p->u.s) + 1;
4518 /* Print the spelling to BUFFER and return it. */
4521 print_spelling (buffer)
4522 register char *buffer;
4524 register char *d = buffer;
4525 register struct spelling *p;
4527 for (p = spelling_base; p < spelling; p++)
4528 if (p->kind == SPELLING_BOUNDS)
4530 sprintf (d, "[%d]", p->u.i);
4535 register const char *s;
4536 if (p->kind == SPELLING_MEMBER)
4538 for (s = p->u.s; (*d = *s++); d++)
4545 /* Issue an error message for a bad initializer component.
4546 MSGID identifies the message.
4547 The component name is taken from the spelling stack. */
4555 error ("%s", msgid);
4556 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4558 error ("(near initialization for `%s')", ofwhat);
4561 /* Issue a pedantic warning for a bad initializer component.
4562 MSGID identifies the message.
4563 The component name is taken from the spelling stack. */
4566 pedwarn_init (msgid)
4571 pedwarn ("%s", msgid);
4572 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4574 pedwarn ("(near initialization for `%s')", ofwhat);
4577 /* Issue a warning for a bad initializer component.
4578 MSGID identifies the message.
4579 The component name is taken from the spelling stack. */
4582 warning_init (msgid)
4587 warning ("%s", msgid);
4588 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4590 warning ("(near initialization for `%s')", ofwhat);
4593 /* Digest the parser output INIT as an initializer for type TYPE.
4594 Return a C expression of type TYPE to represent the initial value.
4596 The arguments REQUIRE_CONSTANT and CONSTRUCTOR_CONSTANT request errors
4597 if non-constant initializers or elements are seen. CONSTRUCTOR_CONSTANT
4598 applies only to elements of constructors. */
4601 digest_init (type, init, require_constant, constructor_constant)
4603 int require_constant, constructor_constant;
4605 enum tree_code code = TREE_CODE (type);
4606 tree inside_init = init;
4608 if (type == error_mark_node
4609 || init == error_mark_node
4610 || TREE_TYPE (init) == error_mark_node)
4611 return error_mark_node;
4613 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4614 /* Do not use STRIP_NOPS here. We do not want an enumerator
4615 whose value is 0 to count as a null pointer constant. */
4616 if (TREE_CODE (init) == NON_LVALUE_EXPR)
4617 inside_init = TREE_OPERAND (init, 0);
4619 /* Initialization of an array of chars from a string constant
4620 optionally enclosed in braces. */
4622 if (code == ARRAY_TYPE)
4624 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4625 if ((typ1 == char_type_node
4626 || typ1 == signed_char_type_node
4627 || typ1 == unsigned_char_type_node
4628 || typ1 == unsigned_wchar_type_node
4629 || typ1 == signed_wchar_type_node)
4630 && ((inside_init && TREE_CODE (inside_init) == STRING_CST)))
4632 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4633 TYPE_MAIN_VARIANT (type)))
4636 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4638 && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node))
4640 error_init ("char-array initialized from wide string");
4641 return error_mark_node;
4643 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4645 && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node))
4647 error_init ("int-array initialized from non-wide string");
4648 return error_mark_node;
4651 TREE_TYPE (inside_init) = type;
4652 if (TYPE_DOMAIN (type) != 0
4653 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4654 /* Subtract 1 (or sizeof (wchar_t))
4655 because it's ok to ignore the terminating null char
4656 that is counted in the length of the constant. */
4657 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4658 TREE_STRING_LENGTH (inside_init)
4659 - ((TYPE_PRECISION (typ1)
4660 != TYPE_PRECISION (char_type_node))
4661 ? (TYPE_PRECISION (wchar_type_node)
4664 pedwarn_init ("initializer-string for array of chars is too long");
4670 /* Any type can be initialized
4671 from an expression of the same type, optionally with braces. */
4673 if (inside_init && TREE_TYPE (inside_init) != 0
4674 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4675 TYPE_MAIN_VARIANT (type))
4676 || (code == ARRAY_TYPE
4677 && comptypes (TREE_TYPE (inside_init), type))
4678 || (code == POINTER_TYPE
4679 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4680 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE)
4681 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4682 TREE_TYPE (type)))))
4684 if (code == POINTER_TYPE
4685 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4686 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE))
4687 inside_init = default_conversion (inside_init);
4688 else if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4689 && TREE_CODE (inside_init) != CONSTRUCTOR)
4691 error_init ("array initialized from non-constant array expression");
4692 return error_mark_node;
4695 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4696 inside_init = decl_constant_value (inside_init);
4698 /* Compound expressions can only occur here if -pedantic or
4699 -pedantic-errors is specified. In the later case, we always want
4700 an error. In the former case, we simply want a warning. */
4701 if (require_constant && pedantic
4702 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4705 = valid_compound_expr_initializer (inside_init,
4706 TREE_TYPE (inside_init));
4707 if (inside_init == error_mark_node)
4708 error_init ("initializer element is not constant");
4710 pedwarn_init ("initializer element is not constant");
4711 if (flag_pedantic_errors)
4712 inside_init = error_mark_node;
4714 else if (require_constant && ! TREE_CONSTANT (inside_init))
4716 error_init ("initializer element is not constant");
4717 inside_init = error_mark_node;
4719 else if (require_constant
4720 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4722 error_init ("initializer element is not computable at load time");
4723 inside_init = error_mark_node;
4729 /* Handle scalar types, including conversions. */
4731 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4732 || code == ENUMERAL_TYPE || code == COMPLEX_TYPE)
4734 /* Note that convert_for_assignment calls default_conversion
4735 for arrays and functions. We must not call it in the
4736 case where inside_init is a null pointer constant. */
4738 = convert_for_assignment (type, init, _("initialization"),
4739 NULL_TREE, NULL_TREE, 0);
4741 if (require_constant && ! TREE_CONSTANT (inside_init))
4743 error_init ("initializer element is not constant");
4744 inside_init = error_mark_node;
4746 else if (require_constant
4747 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4749 error_init ("initializer element is not computable at load time");
4750 inside_init = error_mark_node;
4756 /* Come here only for records and arrays. */
4758 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4760 error_init ("variable-sized object may not be initialized");
4761 return error_mark_node;
4764 /* Traditionally, you can write struct foo x = 0;
4765 and it initializes the first element of x to 0. */
4766 if (flag_traditional)
4768 tree top = 0, prev = 0, otype = type;
4769 while (TREE_CODE (type) == RECORD_TYPE
4770 || TREE_CODE (type) == ARRAY_TYPE
4771 || TREE_CODE (type) == QUAL_UNION_TYPE
4772 || TREE_CODE (type) == UNION_TYPE)
4774 tree temp = build (CONSTRUCTOR, type, NULL_TREE, NULL_TREE);
4778 TREE_OPERAND (prev, 1) = build_tree_list (NULL_TREE, temp);
4780 if (TREE_CODE (type) == ARRAY_TYPE)
4781 type = TREE_TYPE (type);
4782 else if (TYPE_FIELDS (type))
4783 type = TREE_TYPE (TYPE_FIELDS (type));
4786 error_init ("invalid initializer");
4787 return error_mark_node;
4793 TREE_OPERAND (prev, 1)
4794 = build_tree_list (NULL_TREE,
4795 digest_init (type, init, require_constant,
4796 constructor_constant));
4800 return error_mark_node;
4802 error_init ("invalid initializer");
4803 return error_mark_node;
4806 /* Handle initializers that use braces. */
4808 /* Type of object we are accumulating a constructor for.
4809 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4810 static tree constructor_type;
4812 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4814 static tree constructor_fields;
4816 /* For an ARRAY_TYPE, this is the specified index
4817 at which to store the next element we get. */
4818 static tree constructor_index;
4820 /* For an ARRAY_TYPE, this is the end index of the range
4821 to initialize with the next element, or NULL in the ordinary case
4822 where the element is used just once. */
4823 static tree constructor_range_end;
4825 /* For an ARRAY_TYPE, this is the maximum index. */
4826 static tree constructor_max_index;
4828 /* For a RECORD_TYPE, this is the first field not yet written out. */
4829 static tree constructor_unfilled_fields;
4831 /* For an ARRAY_TYPE, this is the index of the first element
4832 not yet written out. */
4833 static tree constructor_unfilled_index;
4835 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4836 This is so we can generate gaps between fields, when appropriate. */
4837 static tree constructor_bit_index;
4839 /* If we are saving up the elements rather than allocating them,
4840 this is the list of elements so far (in reverse order,
4841 most recent first). */
4842 static tree constructor_elements;
4844 /* 1 if so far this constructor's elements are all compile-time constants. */
4845 static int constructor_constant;
4847 /* 1 if so far this constructor's elements are all valid address constants. */
4848 static int constructor_simple;
4850 /* 1 if this constructor is erroneous so far. */
4851 static int constructor_erroneous;
4853 /* 1 if have called defer_addressed_constants. */
4854 static int constructor_subconstants_deferred;
4856 /* Structure for managing pending initializer elements, organized as an
4861 struct init_node *left, *right;
4862 struct init_node *parent;
4868 /* Tree of pending elements at this constructor level.
4869 These are elements encountered out of order
4870 which belong at places we haven't reached yet in actually
4872 Will never hold tree nodes across GC runs. */
4873 static struct init_node *constructor_pending_elts;
4875 /* The SPELLING_DEPTH of this constructor. */
4876 static int constructor_depth;
4878 /* 0 if implicitly pushing constructor levels is allowed. */
4879 int constructor_no_implicit = 0; /* 0 for C; 1 for some other languages. */
4881 static int require_constant_value;
4882 static int require_constant_elements;
4884 /* 1 if it is ok to output this constructor as we read it.
4885 0 means must accumulate a CONSTRUCTOR expression. */
4886 static int constructor_incremental;
4888 /* DECL node for which an initializer is being read.
4889 0 means we are reading a constructor expression
4890 such as (struct foo) {...}. */
4891 static tree constructor_decl;
4893 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4894 static char *constructor_asmspec;
4896 /* Nonzero if this is an initializer for a top-level decl. */
4897 static int constructor_top_level;
4900 /* This stack has a level for each implicit or explicit level of
4901 structuring in the initializer, including the outermost one. It
4902 saves the values of most of the variables above. */
4904 struct constructor_stack
4906 struct constructor_stack *next;
4912 tree unfilled_index;
4913 tree unfilled_fields;
4917 struct init_node *pending_elts;
4919 /* If nonzero, this value should replace the entire
4920 constructor at this level. */
4921 tree replacement_value;
4930 struct constructor_stack *constructor_stack;
4932 /* This stack records separate initializers that are nested.
4933 Nested initializers can't happen in ANSI C, but GNU C allows them
4934 in cases like { ... (struct foo) { ... } ... }. */
4936 struct initializer_stack
4938 struct initializer_stack *next;
4941 struct constructor_stack *constructor_stack;
4943 struct spelling *spelling;
4944 struct spelling *spelling_base;
4948 char require_constant_value;
4949 char require_constant_elements;
4953 struct initializer_stack *initializer_stack;
4955 /* Prepare to parse and output the initializer for variable DECL. */
4958 start_init (decl, asmspec_tree, top_level)
4964 struct initializer_stack *p
4965 = (struct initializer_stack *) xmalloc (sizeof (struct initializer_stack));
4969 asmspec = TREE_STRING_POINTER (asmspec_tree);
4971 p->decl = constructor_decl;
4972 p->asmspec = constructor_asmspec;
4973 p->incremental = constructor_incremental;
4974 p->require_constant_value = require_constant_value;
4975 p->require_constant_elements = require_constant_elements;
4976 p->constructor_stack = constructor_stack;
4977 p->elements = constructor_elements;
4978 p->spelling = spelling;
4979 p->spelling_base = spelling_base;
4980 p->spelling_size = spelling_size;
4981 p->deferred = constructor_subconstants_deferred;
4982 p->top_level = constructor_top_level;
4983 p->next = initializer_stack;
4984 initializer_stack = p;
4986 constructor_decl = decl;
4987 constructor_incremental = top_level;
4988 constructor_asmspec = asmspec;
4989 constructor_subconstants_deferred = 0;
4990 constructor_top_level = top_level;
4994 require_constant_value = TREE_STATIC (decl);
4995 require_constant_elements
4996 = ((TREE_STATIC (decl) || pedantic)
4997 /* For a scalar, you can always use any value to initialize,
4998 even within braces. */
4999 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
5000 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
5001 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
5002 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
5003 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
5004 constructor_incremental
5005 |= (TREE_STATIC (decl) && !DECL_CONTEXT (decl));
5009 require_constant_value = 0;
5010 require_constant_elements = 0;
5011 locus = "(anonymous)";
5014 constructor_stack = 0;
5016 missing_braces_mentioned = 0;
5020 RESTORE_SPELLING_DEPTH (0);
5023 push_string (locus);
5029 struct initializer_stack *p = initializer_stack;
5031 /* Output subconstants (string constants, usually)
5032 that were referenced within this initializer and saved up.
5033 Must do this if and only if we called defer_addressed_constants. */
5034 if (constructor_subconstants_deferred)
5035 output_deferred_addressed_constants ();
5037 /* Free the whole constructor stack of this initializer. */
5038 while (constructor_stack)
5040 struct constructor_stack *q = constructor_stack;
5041 constructor_stack = q->next;
5045 /* Pop back to the data of the outer initializer (if any). */
5046 constructor_decl = p->decl;
5047 constructor_asmspec = p->asmspec;
5048 constructor_incremental = p->incremental;
5049 require_constant_value = p->require_constant_value;
5050 require_constant_elements = p->require_constant_elements;
5051 constructor_stack = p->constructor_stack;
5052 constructor_elements = p->elements;
5053 spelling = p->spelling;
5054 spelling_base = p->spelling_base;
5055 spelling_size = p->spelling_size;
5056 constructor_subconstants_deferred = p->deferred;
5057 constructor_top_level = p->top_level;
5058 initializer_stack = p->next;
5062 /* Call here when we see the initializer is surrounded by braces.
5063 This is instead of a call to push_init_level;
5064 it is matched by a call to pop_init_level.
5066 TYPE is the type to initialize, for a constructor expression.
5067 For an initializer for a decl, TYPE is zero. */
5070 really_start_incremental_init (type)
5073 struct constructor_stack *p
5074 = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5077 type = TREE_TYPE (constructor_decl);
5079 /* Turn off constructor_incremental if type is a struct with bitfields.
5080 Do this before the first push, so that the corrected value
5081 is available in finish_init. */
5082 check_init_type_bitfields (type);
5084 p->type = constructor_type;
5085 p->fields = constructor_fields;
5086 p->index = constructor_index;
5087 p->range_end = constructor_range_end;
5088 p->max_index = constructor_max_index;
5089 p->unfilled_index = constructor_unfilled_index;
5090 p->unfilled_fields = constructor_unfilled_fields;
5091 p->bit_index = constructor_bit_index;
5092 p->elements = constructor_elements;
5093 p->constant = constructor_constant;
5094 p->simple = constructor_simple;
5095 p->erroneous = constructor_erroneous;
5096 p->pending_elts = constructor_pending_elts;
5097 p->depth = constructor_depth;
5098 p->replacement_value = 0;
5100 p->incremental = constructor_incremental;
5103 constructor_stack = p;
5105 constructor_constant = 1;
5106 constructor_simple = 1;
5107 constructor_depth = SPELLING_DEPTH ();
5108 constructor_elements = 0;
5109 constructor_pending_elts = 0;
5110 constructor_type = type;
5112 if (TREE_CODE (constructor_type) == RECORD_TYPE
5113 || TREE_CODE (constructor_type) == UNION_TYPE)
5115 constructor_fields = TYPE_FIELDS (constructor_type);
5116 /* Skip any nameless bit fields at the beginning. */
5117 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5118 && DECL_NAME (constructor_fields) == 0)
5119 constructor_fields = TREE_CHAIN (constructor_fields);
5121 constructor_unfilled_fields = constructor_fields;
5122 constructor_bit_index = bitsize_zero_node;
5124 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5126 constructor_range_end = 0;
5127 if (TYPE_DOMAIN (constructor_type))
5129 constructor_max_index
5130 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5132 = convert (bitsizetype,
5133 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5136 constructor_index = bitsize_zero_node;
5138 constructor_unfilled_index = constructor_index;
5142 /* Handle the case of int x = {5}; */
5143 constructor_fields = constructor_type;
5144 constructor_unfilled_fields = constructor_type;
5147 if (constructor_incremental)
5149 make_decl_rtl (constructor_decl, constructor_asmspec,
5150 constructor_top_level);
5151 assemble_variable (constructor_decl, constructor_top_level, 0, 1);
5153 defer_addressed_constants ();
5154 constructor_subconstants_deferred = 1;
5158 /* Push down into a subobject, for initialization.
5159 If this is for an explicit set of braces, IMPLICIT is 0.
5160 If it is because the next element belongs at a lower level,
5164 push_init_level (implicit)
5167 struct constructor_stack *p;
5169 /* If we've exhausted any levels that didn't have braces,
5171 while (constructor_stack->implicit)
5173 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5174 || TREE_CODE (constructor_type) == UNION_TYPE)
5175 && constructor_fields == 0)
5176 process_init_element (pop_init_level (1));
5177 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5178 && tree_int_cst_lt (constructor_max_index, constructor_index))
5179 process_init_element (pop_init_level (1));
5184 /* Structure elements may require alignment. Do this now if necessary
5185 for the subaggregate, and if it comes next in sequence. Don't do
5186 this for subaggregates that will go on the pending list. */
5187 if (constructor_incremental && constructor_type != 0
5188 && TREE_CODE (constructor_type) == RECORD_TYPE && constructor_fields
5189 && constructor_fields == constructor_unfilled_fields)
5191 /* Advance to offset of this element. */
5192 if (! tree_int_cst_equal (constructor_bit_index,
5193 bit_position (constructor_fields)))
5196 (size_binop (TRUNC_DIV_EXPR,
5197 size_binop (MINUS_EXPR,
5198 bit_position (constructor_fields),
5199 constructor_bit_index),
5203 /* Indicate that we have now filled the structure up to the current
5205 constructor_unfilled_fields = constructor_fields;
5208 p = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5209 p->type = constructor_type;
5210 p->fields = constructor_fields;
5211 p->index = constructor_index;
5212 p->range_end = constructor_range_end;
5213 p->max_index = constructor_max_index;
5214 p->unfilled_index = constructor_unfilled_index;
5215 p->unfilled_fields = constructor_unfilled_fields;
5216 p->bit_index = constructor_bit_index;
5217 p->elements = constructor_elements;
5218 p->constant = constructor_constant;
5219 p->simple = constructor_simple;
5220 p->erroneous = constructor_erroneous;
5221 p->pending_elts = constructor_pending_elts;
5222 p->depth = constructor_depth;
5223 p->replacement_value = 0;
5224 p->implicit = implicit;
5225 p->incremental = constructor_incremental;
5227 p->next = constructor_stack;
5228 constructor_stack = p;
5230 constructor_constant = 1;
5231 constructor_simple = 1;
5232 constructor_depth = SPELLING_DEPTH ();
5233 constructor_elements = 0;
5234 constructor_pending_elts = 0;
5236 /* Don't die if an entire brace-pair level is superfluous
5237 in the containing level. */
5238 if (constructor_type == 0)
5240 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5241 || TREE_CODE (constructor_type) == UNION_TYPE)
5243 /* Don't die if there are extra init elts at the end. */
5244 if (constructor_fields == 0)
5245 constructor_type = 0;
5248 constructor_type = TREE_TYPE (constructor_fields);
5249 push_member_name (constructor_fields);
5250 constructor_depth++;
5251 if (constructor_fields != constructor_unfilled_fields)
5252 constructor_incremental = 0;
5255 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5257 constructor_type = TREE_TYPE (constructor_type);
5258 push_array_bounds (tree_low_cst (constructor_index, 0));
5259 constructor_depth++;
5260 if (! tree_int_cst_equal (constructor_index, constructor_unfilled_index)
5261 || constructor_range_end != 0)
5262 constructor_incremental = 0;
5265 if (constructor_type == 0)
5267 error_init ("extra brace group at end of initializer");
5268 constructor_fields = 0;
5269 constructor_unfilled_fields = 0;
5273 /* Turn off constructor_incremental if type is a struct with bitfields. */
5274 check_init_type_bitfields (constructor_type);
5276 if (implicit && warn_missing_braces && !missing_braces_mentioned)
5278 missing_braces_mentioned = 1;
5279 warning_init ("missing braces around initializer");
5282 if (TREE_CODE (constructor_type) == RECORD_TYPE
5283 || TREE_CODE (constructor_type) == UNION_TYPE)
5285 constructor_fields = TYPE_FIELDS (constructor_type);
5286 /* Skip any nameless bit fields at the beginning. */
5287 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5288 && DECL_NAME (constructor_fields) == 0)
5289 constructor_fields = TREE_CHAIN (constructor_fields);
5291 constructor_unfilled_fields = constructor_fields;
5292 constructor_bit_index = bitsize_zero_node;
5294 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5296 constructor_range_end = 0;
5297 if (TYPE_DOMAIN (constructor_type))
5299 constructor_max_index
5300 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5302 = convert (bitsizetype,
5304 (TYPE_DOMAIN (constructor_type)));
5307 constructor_index = bitsize_zero_node;
5309 constructor_unfilled_index = constructor_index;
5313 warning_init ("braces around scalar initializer");
5314 constructor_fields = constructor_type;
5315 constructor_unfilled_fields = constructor_type;
5319 /* Don't read a struct incrementally if it has any bitfields,
5320 because the incremental reading code doesn't know how to
5321 handle bitfields yet. */
5324 check_init_type_bitfields (type)
5327 if (TREE_CODE (type) == RECORD_TYPE)
5330 for (tail = TYPE_FIELDS (type); tail;
5331 tail = TREE_CHAIN (tail))
5333 if (DECL_C_BIT_FIELD (tail))
5335 constructor_incremental = 0;
5339 check_init_type_bitfields (TREE_TYPE (tail));
5343 else if (TREE_CODE (type) == UNION_TYPE)
5345 tree tail = TYPE_FIELDS (type);
5346 if (tail && DECL_C_BIT_FIELD (tail))
5347 /* We also use the nonincremental algorithm for initiliazation
5348 of unions whose first member is a bitfield, becuase the
5349 incremental algorithm has no code for dealing with
5351 constructor_incremental = 0;
5354 else if (TREE_CODE (type) == ARRAY_TYPE)
5355 check_init_type_bitfields (TREE_TYPE (type));
5358 /* At the end of an implicit or explicit brace level,
5359 finish up that level of constructor.
5360 If we were outputting the elements as they are read, return 0
5361 from inner levels (process_init_element ignores that),
5362 but return error_mark_node from the outermost level
5363 (that's what we want to put in DECL_INITIAL).
5364 Otherwise, return a CONSTRUCTOR expression. */
5367 pop_init_level (implicit)
5370 struct constructor_stack *p;
5371 HOST_WIDE_INT size = 0;
5372 tree constructor = 0;
5376 /* When we come to an explicit close brace,
5377 pop any inner levels that didn't have explicit braces. */
5378 while (constructor_stack->implicit)
5379 process_init_element (pop_init_level (1));
5382 p = constructor_stack;
5384 if (constructor_type != 0)
5385 size = int_size_in_bytes (constructor_type);
5387 /* Warn when some struct elements are implicitly initialized to zero. */
5390 && TREE_CODE (constructor_type) == RECORD_TYPE
5391 && constructor_unfilled_fields)
5393 push_member_name (constructor_unfilled_fields);
5394 warning_init ("missing initializer");
5395 RESTORE_SPELLING_DEPTH (constructor_depth);
5398 /* Now output all pending elements. */
5399 output_pending_init_elements (1);
5401 #if 0 /* c-parse.in warns about {}. */
5402 /* In ANSI, each brace level must have at least one element. */
5403 if (! implicit && pedantic
5404 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5405 ? integer_zerop (constructor_unfilled_index)
5406 : constructor_unfilled_fields == TYPE_FIELDS (constructor_type)))
5407 pedwarn_init ("empty braces in initializer");
5410 /* Pad out the end of the structure. */
5412 if (p->replacement_value)
5414 /* If this closes a superfluous brace pair,
5415 just pass out the element between them. */
5416 constructor = p->replacement_value;
5417 /* If this is the top level thing within the initializer,
5418 and it's for a variable, then since we already called
5419 assemble_variable, we must output the value now. */
5420 if (p->next == 0 && constructor_decl != 0
5421 && constructor_incremental)
5423 constructor = digest_init (constructor_type, constructor,
5424 require_constant_value,
5425 require_constant_elements);
5427 /* If initializing an array of unknown size,
5428 determine the size now. */
5429 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5430 && TYPE_DOMAIN (constructor_type) == 0)
5432 /* We shouldn't have an incomplete array type within
5434 if (constructor_stack->next)
5437 if (complete_array_type (constructor_type, constructor, 0))
5440 size = int_size_in_bytes (constructor_type);
5443 output_constant (constructor, size);
5446 else if (constructor_type == 0)
5448 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5449 && TREE_CODE (constructor_type) != UNION_TYPE
5450 && TREE_CODE (constructor_type) != ARRAY_TYPE
5451 && ! constructor_incremental)
5453 /* A nonincremental scalar initializer--just return
5454 the element, after verifying there is just one. */
5455 if (constructor_elements == 0)
5457 error_init ("empty scalar initializer");
5458 constructor = error_mark_node;
5460 else if (TREE_CHAIN (constructor_elements) != 0)
5462 error_init ("extra elements in scalar initializer");
5463 constructor = TREE_VALUE (constructor_elements);
5466 constructor = TREE_VALUE (constructor_elements);
5468 else if (! constructor_incremental)
5470 if (constructor_erroneous)
5471 constructor = error_mark_node;
5474 constructor = build (CONSTRUCTOR, constructor_type, NULL_TREE,
5475 nreverse (constructor_elements));
5476 if (constructor_constant)
5477 TREE_CONSTANT (constructor) = 1;
5478 if (constructor_constant && constructor_simple)
5479 TREE_STATIC (constructor) = 1;
5486 if (TREE_CODE (constructor_type) == RECORD_TYPE
5487 || TREE_CODE (constructor_type) == UNION_TYPE)
5488 /* Find the offset of the end of that field. */
5489 filled = size_binop (CEIL_DIV_EXPR, constructor_bit_index,
5492 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5494 /* If initializing an array of unknown size,
5495 determine the size now. */
5496 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5497 && TYPE_DOMAIN (constructor_type) == 0)
5500 = copy_node (size_diffop (constructor_unfilled_index,
5503 TYPE_DOMAIN (constructor_type) = build_index_type (maxindex);
5504 TREE_TYPE (maxindex) = TYPE_DOMAIN (constructor_type);
5506 /* TYPE_MAX_VALUE is always one less than the number of elements
5507 in the array, because we start counting at zero. Therefore,
5508 warn only if the value is less than zero. */
5510 && (tree_int_cst_sgn
5511 (TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5513 error_with_decl (constructor_decl,
5514 "zero or negative array size `%s'");
5516 layout_type (constructor_type);
5517 size = int_size_in_bytes (constructor_type);
5521 = size_binop (MULT_EXPR, constructor_unfilled_index,
5522 convert (bitsizetype,
5524 (TREE_TYPE (constructor_type))));
5530 assemble_zeros (size - tree_low_cst (filled, 1));
5534 constructor_type = p->type;
5535 constructor_fields = p->fields;
5536 constructor_index = p->index;
5537 constructor_range_end = p->range_end;
5538 constructor_max_index = p->max_index;
5539 constructor_unfilled_index = p->unfilled_index;
5540 constructor_unfilled_fields = p->unfilled_fields;
5541 constructor_bit_index = p->bit_index;
5542 constructor_elements = p->elements;
5543 constructor_constant = p->constant;
5544 constructor_simple = p->simple;
5545 constructor_erroneous = p->erroneous;
5546 constructor_pending_elts = p->pending_elts;
5547 constructor_depth = p->depth;
5548 constructor_incremental = p->incremental;
5549 RESTORE_SPELLING_DEPTH (constructor_depth);
5551 constructor_stack = p->next;
5554 if (constructor == 0)
5556 if (constructor_stack == 0)
5557 return error_mark_node;
5563 /* Within an array initializer, specify the next index to be initialized.
5564 FIRST is that index. If LAST is nonzero, then initialize a range
5565 of indices, running from FIRST through LAST. */
5568 set_init_index (first, last)
5571 while ((TREE_CODE (first) == NOP_EXPR
5572 || TREE_CODE (first) == CONVERT_EXPR
5573 || TREE_CODE (first) == NON_LVALUE_EXPR)
5574 && (TYPE_MODE (TREE_TYPE (first))
5575 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0)))))
5576 first = TREE_OPERAND (first, 0);
5579 while ((TREE_CODE (last) == NOP_EXPR
5580 || TREE_CODE (last) == CONVERT_EXPR
5581 || TREE_CODE (last) == NON_LVALUE_EXPR)
5582 && (TYPE_MODE (TREE_TYPE (last))
5583 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0)))))
5584 last = TREE_OPERAND (last, 0);
5586 if (TREE_CODE (first) != INTEGER_CST)
5587 error_init ("nonconstant array index in initializer");
5588 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5589 error_init ("nonconstant array index in initializer");
5590 else if (! constructor_unfilled_index)
5591 error_init ("array index in non-array initializer");
5592 else if (tree_int_cst_lt (first, constructor_unfilled_index))
5593 error_init ("duplicate array index in initializer");
5596 constructor_index = convert (bitsizetype, first);
5598 if (last != 0 && tree_int_cst_lt (last, first))
5599 error_init ("empty index range in initializer");
5603 pedwarn ("ISO C89 forbids specifying element to initialize");
5605 constructor_range_end = last ? convert (bitsizetype, last) : 0;
5610 /* Within a struct initializer, specify the next field to be initialized. */
5613 set_init_label (fieldname)
5619 /* Don't die if an entire brace-pair level is superfluous
5620 in the containing level. */
5621 if (constructor_type == 0)
5624 for (tail = TYPE_FIELDS (constructor_type); tail;
5625 tail = TREE_CHAIN (tail))
5627 if (tail == constructor_unfilled_fields)
5629 if (DECL_NAME (tail) == fieldname)
5634 error ("unknown field `%s' specified in initializer",
5635 IDENTIFIER_POINTER (fieldname));
5637 error ("field `%s' already initialized",
5638 IDENTIFIER_POINTER (fieldname));
5641 constructor_fields = tail;
5643 pedwarn ("ISO C89 forbids specifying structure member to initialize");
5647 /* Add a new initializer to the tree of pending initializers. PURPOSE
5648 indentifies the initializer, either array index or field in a structure.
5649 VALUE is the value of that index or field. */
5652 add_pending_init (purpose, value)
5653 tree purpose, value;
5655 struct init_node *p, **q, *r;
5657 q = &constructor_pending_elts;
5660 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5665 if (tree_int_cst_lt (purpose, p->purpose))
5667 else if (p->purpose != purpose)
5678 if (tree_int_cst_lt (bit_position (purpose),
5679 bit_position (p->purpose)))
5681 else if (p->purpose != purpose)
5688 r = (struct init_node *) ggc_alloc (sizeof (struct init_node));
5689 r->purpose = purpose;
5700 struct init_node *s;
5704 if (p->balance == 0)
5706 else if (p->balance < 0)
5713 p->left->parent = p;
5730 constructor_pending_elts = r;
5735 struct init_node *t = r->right;
5739 r->right->parent = r;
5744 p->left->parent = p;
5747 p->balance = t->balance < 0;
5748 r->balance = -(t->balance > 0);
5763 constructor_pending_elts = t;
5769 /* p->balance == +1; growth of left side balances the node. */
5774 else /* r == p->right */
5776 if (p->balance == 0)
5777 /* Growth propagation from right side. */
5779 else if (p->balance > 0)
5786 p->right->parent = p;
5803 constructor_pending_elts = r;
5805 else /* r->balance == -1 */
5808 struct init_node *t = r->left;
5812 r->left->parent = r;
5817 p->right->parent = p;
5820 r->balance = (t->balance < 0);
5821 p->balance = -(t->balance > 0);
5836 constructor_pending_elts = t;
5842 /* p->balance == -1; growth of right side balances the node. */
5853 /* Return nonzero if FIELD is equal to the index of a pending initializer. */
5856 pending_init_member (field)
5859 struct init_node *p;
5861 p = constructor_pending_elts;
5862 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5866 if (field == p->purpose)
5868 else if (tree_int_cst_lt (field, p->purpose))
5878 if (field == p->purpose)
5880 else if (tree_int_cst_lt (bit_position (field),
5881 bit_position (p->purpose)))
5891 /* "Output" the next constructor element.
5892 At top level, really output it to assembler code now.
5893 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5894 TYPE is the data type that the containing data type wants here.
5895 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5897 PENDING if non-nil means output pending elements that belong
5898 right after this element. (PENDING is normally 1;
5899 it is 0 while outputting pending elements, to avoid recursion.) */
5902 output_init_element (value, type, field, pending)
5903 tree value, type, field;
5908 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5909 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5910 && !(TREE_CODE (value) == STRING_CST
5911 && TREE_CODE (type) == ARRAY_TYPE
5912 && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE)
5913 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5914 TYPE_MAIN_VARIANT (type))))
5915 value = default_conversion (value);
5917 if (value == error_mark_node)
5918 constructor_erroneous = 1;
5919 else if (!TREE_CONSTANT (value))
5920 constructor_constant = 0;
5921 else if (initializer_constant_valid_p (value, TREE_TYPE (value)) == 0
5922 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5923 || TREE_CODE (constructor_type) == UNION_TYPE)
5924 && DECL_C_BIT_FIELD (field)
5925 && TREE_CODE (value) != INTEGER_CST))
5926 constructor_simple = 0;
5928 if (require_constant_value && ! TREE_CONSTANT (value))
5930 error_init ("initializer element is not constant");
5931 value = error_mark_node;
5933 else if (require_constant_elements
5934 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
5936 error_init ("initializer element is not computable at load time");
5937 value = error_mark_node;
5940 /* If this element duplicates one on constructor_pending_elts,
5941 print a message and ignore it. Don't do this when we're
5942 processing elements taken off constructor_pending_elts,
5943 because we'd always get spurious errors. */
5946 if (TREE_CODE (constructor_type) == RECORD_TYPE
5947 || TREE_CODE (constructor_type) == UNION_TYPE
5948 || TREE_CODE (constructor_type) == ARRAY_TYPE)
5950 if (pending_init_member (field))
5952 error_init ("duplicate initializer");
5958 /* If this element doesn't come next in sequence,
5959 put it on constructor_pending_elts. */
5960 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5961 && ! tree_int_cst_equal (field, constructor_unfilled_index))
5964 add_pending_init (field,
5965 digest_init (type, value, require_constant_value,
5966 require_constant_elements));
5968 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5969 && field != constructor_unfilled_fields)
5971 /* We do this for records but not for unions. In a union,
5972 no matter which field is specified, it can be initialized
5973 right away since it starts at the beginning of the union. */
5975 add_pending_init (field,
5976 digest_init (type, value, require_constant_value,
5977 require_constant_elements));
5981 /* Otherwise, output this element either to
5982 constructor_elements or to the assembler file. */
5986 if (! constructor_incremental)
5988 if (field && TREE_CODE (field) == INTEGER_CST)
5989 field = copy_node (field);
5990 constructor_elements
5991 = tree_cons (field, digest_init (type, value,
5992 require_constant_value,
5993 require_constant_elements),
5994 constructor_elements);
5998 /* Structure elements may require alignment.
5999 Do this, if necessary. */
6000 if (TREE_CODE (constructor_type) == RECORD_TYPE
6001 && ! tree_int_cst_equal (constructor_bit_index,
6002 bit_position (field)))
6003 /* Advance to offset of this element. */
6006 (size_binop (TRUNC_DIV_EXPR,
6007 size_binop (MINUS_EXPR, bit_position (field),
6008 constructor_bit_index),
6012 output_constant (digest_init (type, value,
6013 require_constant_value,
6014 require_constant_elements),
6015 int_size_in_bytes (type));
6017 /* For a record or union,
6018 keep track of end position of last field. */
6019 if (TREE_CODE (constructor_type) == RECORD_TYPE
6020 || TREE_CODE (constructor_type) == UNION_TYPE)
6021 constructor_bit_index
6022 = size_binop (PLUS_EXPR, bit_position (field),
6027 /* Advance the variable that indicates sequential elements output. */
6028 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6029 constructor_unfilled_index
6030 = size_binop (PLUS_EXPR, constructor_unfilled_index,
6032 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6034 constructor_unfilled_fields
6035 = TREE_CHAIN (constructor_unfilled_fields);
6037 /* Skip any nameless bit fields. */
6038 while (constructor_unfilled_fields != 0
6039 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6040 && DECL_NAME (constructor_unfilled_fields) == 0)
6041 constructor_unfilled_fields =
6042 TREE_CHAIN (constructor_unfilled_fields);
6044 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6045 constructor_unfilled_fields = 0;
6047 /* Now output any pending elements which have become next. */
6049 output_pending_init_elements (0);
6053 /* Output any pending elements which have become next.
6054 As we output elements, constructor_unfilled_{fields,index}
6055 advances, which may cause other elements to become next;
6056 if so, they too are output.
6058 If ALL is 0, we return when there are
6059 no more pending elements to output now.
6061 If ALL is 1, we output space as necessary so that
6062 we can output all the pending elements. */
6065 output_pending_init_elements (all)
6068 struct init_node *elt = constructor_pending_elts;
6073 /* Look thru the whole pending tree.
6074 If we find an element that should be output now,
6075 output it. Otherwise, set NEXT to the element
6076 that comes first among those still pending. */
6081 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6083 if (tree_int_cst_equal (elt->purpose,
6084 constructor_unfilled_index))
6085 output_init_element (elt->value,
6086 TREE_TYPE (constructor_type),
6087 constructor_unfilled_index, 0);
6088 else if (tree_int_cst_lt (constructor_unfilled_index,
6091 /* Advance to the next smaller node. */
6096 /* We have reached the smallest node bigger than the
6097 current unfilled index. Fill the space first. */
6098 next = elt->purpose;
6104 /* Advance to the next bigger node. */
6109 /* We have reached the biggest node in a subtree. Find
6110 the parent of it, which is the next bigger node. */
6111 while (elt->parent && elt->parent->right == elt)
6114 if (elt && tree_int_cst_lt (constructor_unfilled_index,
6117 next = elt->purpose;
6123 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6124 || TREE_CODE (constructor_type) == UNION_TYPE)
6126 /* If the current record is complete we are done. */
6127 if (constructor_unfilled_fields == 0)
6129 if (elt->purpose == constructor_unfilled_fields)
6131 output_init_element (elt->value,
6132 TREE_TYPE (constructor_unfilled_fields),
6133 constructor_unfilled_fields,
6136 else if (tree_int_cst_lt (bit_position (constructor_unfilled_fields),
6137 bit_position (elt->purpose)))
6139 /* Advance to the next smaller node. */
6144 /* We have reached the smallest node bigger than the
6145 current unfilled field. Fill the space first. */
6146 next = elt->purpose;
6152 /* Advance to the next bigger node. */
6157 /* We have reached the biggest node in a subtree. Find
6158 the parent of it, which is the next bigger node. */
6159 while (elt->parent && elt->parent->right == elt)
6164 (bit_position (constructor_unfilled_fields),
6165 bit_position (elt->purpose))))
6167 next = elt->purpose;
6175 /* Ordinarily return, but not if we want to output all
6176 and there are elements left. */
6177 if (! (all && next != 0))
6180 /* Generate space up to the position of NEXT. */
6181 if (constructor_incremental)
6184 tree nextpos_tree = bitsize_zero_node;
6186 if (TREE_CODE (constructor_type) == RECORD_TYPE
6187 || TREE_CODE (constructor_type) == UNION_TYPE)
6191 /* Find the last field written out, if any. */
6192 for (tail = TYPE_FIELDS (constructor_type); tail;
6193 tail = TREE_CHAIN (tail))
6194 if (TREE_CHAIN (tail) == constructor_unfilled_fields)
6198 /* Find the offset of the end of that field. */
6199 filled = size_binop (CEIL_DIV_EXPR,
6200 size_binop (PLUS_EXPR, bit_position (tail),
6204 filled = bitsize_zero_node;
6206 nextpos_tree = convert (bitsizetype, byte_position (next));
6207 constructor_bit_index = bit_position (next);
6208 constructor_unfilled_fields = next;
6210 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6213 = size_binop (MULT_EXPR, constructor_unfilled_index,
6214 convert (bitsizetype,
6216 (TREE_TYPE (constructor_type))));
6218 = size_binop (MULT_EXPR, next,
6219 convert (bitsizetype, TYPE_SIZE_UNIT
6220 (TREE_TYPE (constructor_type))));
6221 constructor_unfilled_index = next;
6227 assemble_zeros (tree_low_cst (size_diffop (nextpos_tree, filled), 1));
6231 /* If it's not incremental, just skip over the gap,
6232 so that after jumping to retry we will output the next
6233 successive element. */
6234 if (TREE_CODE (constructor_type) == RECORD_TYPE
6235 || TREE_CODE (constructor_type) == UNION_TYPE)
6236 constructor_unfilled_fields = next;
6237 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6238 constructor_unfilled_index = next;
6241 /* ELT now points to the node in the pending tree with the next
6242 initializer to output. */
6246 /* Add one non-braced element to the current constructor level.
6247 This adjusts the current position within the constructor's type.
6248 This may also start or terminate implicit levels
6249 to handle a partly-braced initializer.
6251 Once this has found the correct level for the new element,
6252 it calls output_init_element.
6254 Note: if we are incrementally outputting this constructor,
6255 this function may be called with a null argument
6256 representing a sub-constructor that was already incrementally output.
6257 When that happens, we output nothing, but we do the bookkeeping
6258 to skip past that element of the current constructor. */
6261 process_init_element (value)
6264 tree orig_value = value;
6265 int string_flag = value != 0 && TREE_CODE (value) == STRING_CST;
6267 /* Handle superfluous braces around string cst as in
6268 char x[] = {"foo"}; */
6271 && TREE_CODE (constructor_type) == ARRAY_TYPE
6272 && TREE_CODE (TREE_TYPE (constructor_type)) == INTEGER_TYPE
6273 && integer_zerop (constructor_unfilled_index))
6275 if (constructor_stack->replacement_value)
6276 error_init ("excess elements in char array initializer");
6277 constructor_stack->replacement_value = value;
6281 if (constructor_stack->replacement_value != 0)
6283 error_init ("excess elements in struct initializer");
6287 /* Ignore elements of a brace group if it is entirely superfluous
6288 and has already been diagnosed. */
6289 if (constructor_type == 0)
6292 /* If we've exhausted any levels that didn't have braces,
6294 while (constructor_stack->implicit)
6296 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6297 || TREE_CODE (constructor_type) == UNION_TYPE)
6298 && constructor_fields == 0)
6299 process_init_element (pop_init_level (1));
6300 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6301 && (constructor_max_index == 0
6302 || tree_int_cst_lt (constructor_max_index,
6303 constructor_index)))
6304 process_init_element (pop_init_level (1));
6311 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6314 enum tree_code fieldcode;
6316 if (constructor_fields == 0)
6318 pedwarn_init ("excess elements in struct initializer");
6322 fieldtype = TREE_TYPE (constructor_fields);
6323 if (fieldtype != error_mark_node)
6324 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6325 fieldcode = TREE_CODE (fieldtype);
6327 /* Accept a string constant to initialize a subarray. */
6329 && fieldcode == ARRAY_TYPE
6330 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6333 /* Otherwise, if we have come to a subaggregate,
6334 and we don't have an element of its type, push into it. */
6335 else if (value != 0 && !constructor_no_implicit
6336 && value != error_mark_node
6337 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6338 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6339 || fieldcode == UNION_TYPE))
6341 push_init_level (1);
6347 push_member_name (constructor_fields);
6348 output_init_element (value, fieldtype, constructor_fields, 1);
6349 RESTORE_SPELLING_DEPTH (constructor_depth);
6352 /* Do the bookkeeping for an element that was
6353 directly output as a constructor. */
6355 /* For a record, keep track of end position of last field. */
6356 constructor_bit_index
6357 = size_binop (PLUS_EXPR,
6358 bit_position (constructor_fields),
6359 DECL_SIZE (constructor_fields));
6361 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6362 /* Skip any nameless bit fields. */
6363 while (constructor_unfilled_fields != 0
6364 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6365 && DECL_NAME (constructor_unfilled_fields) == 0)
6366 constructor_unfilled_fields =
6367 TREE_CHAIN (constructor_unfilled_fields);
6370 constructor_fields = TREE_CHAIN (constructor_fields);
6371 /* Skip any nameless bit fields at the beginning. */
6372 while (constructor_fields != 0
6373 && DECL_C_BIT_FIELD (constructor_fields)
6374 && DECL_NAME (constructor_fields) == 0)
6375 constructor_fields = TREE_CHAIN (constructor_fields);
6378 if (TREE_CODE (constructor_type) == UNION_TYPE)
6381 enum tree_code fieldcode;
6383 if (constructor_fields == 0)
6385 pedwarn_init ("excess elements in union initializer");
6389 fieldtype = TREE_TYPE (constructor_fields);
6390 if (fieldtype != error_mark_node)
6391 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6392 fieldcode = TREE_CODE (fieldtype);
6394 /* Warn that traditional C rejects initialization of unions.
6395 We skip the warning if the value is zero. This is done
6396 under the assumption that the zero initializer in user
6397 code appears conditioned on e.g. __STDC__ to avoid
6398 "missing initializer" warnings and relies on default
6399 initialization to zero in the traditional C case. */
6400 if (warn_traditional && !in_system_header
6401 && !(value && (integer_zerop (value) || real_zerop (value))))
6402 warning ("traditional C rejects initialization of unions");
6404 /* Accept a string constant to initialize a subarray. */
6406 && fieldcode == ARRAY_TYPE
6407 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6410 /* Otherwise, if we have come to a subaggregate,
6411 and we don't have an element of its type, push into it. */
6412 else if (value != 0 && !constructor_no_implicit
6413 && value != error_mark_node
6414 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6415 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6416 || fieldcode == UNION_TYPE))
6418 push_init_level (1);
6424 push_member_name (constructor_fields);
6425 output_init_element (value, fieldtype, constructor_fields, 1);
6426 RESTORE_SPELLING_DEPTH (constructor_depth);
6429 /* Do the bookkeeping for an element that was
6430 directly output as a constructor. */
6432 constructor_bit_index = DECL_SIZE (constructor_fields);
6433 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6436 constructor_fields = 0;
6439 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6441 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6442 enum tree_code eltcode = TREE_CODE (elttype);
6444 /* Accept a string constant to initialize a subarray. */
6446 && eltcode == ARRAY_TYPE
6447 && TREE_CODE (TREE_TYPE (elttype)) == INTEGER_TYPE
6450 /* Otherwise, if we have come to a subaggregate,
6451 and we don't have an element of its type, push into it. */
6452 else if (value != 0 && !constructor_no_implicit
6453 && value != error_mark_node
6454 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != elttype
6455 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6456 || eltcode == UNION_TYPE))
6458 push_init_level (1);
6462 if (constructor_max_index != 0
6463 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6464 || integer_all_onesp (constructor_max_index)))
6466 pedwarn_init ("excess elements in array initializer");
6470 /* In the case of [LO .. HI] = VALUE, only evaluate VALUE once. */
6471 if (constructor_range_end)
6473 if (constructor_max_index != 0
6474 && tree_int_cst_lt (constructor_max_index,
6475 constructor_range_end))
6477 pedwarn_init ("excess elements in array initializer");
6478 constructor_range_end = constructor_max_index;
6481 value = save_expr (value);
6484 /* Now output the actual element.
6485 Ordinarily, output once.
6486 If there is a range, repeat it till we advance past the range. */
6491 push_array_bounds (tree_low_cst (constructor_index, 0));
6492 output_init_element (value, elttype, constructor_index, 1);
6493 RESTORE_SPELLING_DEPTH (constructor_depth);
6497 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6500 /* If we are doing the bookkeeping for an element that was
6501 directly output as a constructor, we must update
6502 constructor_unfilled_index. */
6503 constructor_unfilled_index = constructor_index;
6505 while (! (constructor_range_end == 0
6506 || tree_int_cst_lt (constructor_range_end,
6507 constructor_index)));
6512 /* Handle the sole element allowed in a braced initializer
6513 for a scalar variable. */
6514 if (constructor_fields == 0)
6516 pedwarn_init ("excess elements in scalar initializer");
6521 output_init_element (value, constructor_type, NULL_TREE, 1);
6522 constructor_fields = 0;
6527 /* Expand an ASM statement with operands, handling output operands
6528 that are not variables or INDIRECT_REFS by transforming such
6529 cases into cases that expand_asm_operands can handle.
6531 Arguments are same as for expand_asm_operands. */
6534 c_expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line)
6535 tree string, outputs, inputs, clobbers;
6537 const char *filename;
6540 int noutputs = list_length (outputs);
6542 /* o[I] is the place that output number I should be written. */
6543 register tree *o = (tree *) alloca (noutputs * sizeof (tree));
6546 if (TREE_CODE (string) == ADDR_EXPR)
6547 string = TREE_OPERAND (string, 0);
6548 if (last_tree && TREE_CODE (string) != STRING_CST)
6550 error ("asm template is not a string constant");
6554 /* Record the contents of OUTPUTS before it is modified. */
6555 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6557 tree output = TREE_VALUE (tail);
6559 /* We can remove conversions that just change the type, not the mode. */
6560 STRIP_NOPS (output);
6563 /* Allow conversions as LHS here. build_modify_expr as called below
6564 will do the right thing with them. */
6565 while (TREE_CODE (output) == NOP_EXPR
6566 || TREE_CODE (output) == CONVERT_EXPR
6567 || TREE_CODE (output) == FLOAT_EXPR
6568 || TREE_CODE (output) == FIX_TRUNC_EXPR
6569 || TREE_CODE (output) == FIX_FLOOR_EXPR
6570 || TREE_CODE (output) == FIX_ROUND_EXPR
6571 || TREE_CODE (output) == FIX_CEIL_EXPR)
6572 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));
6588 add_stmt (build_stmt (ASM_STMT,
6589 vol ? ridpointers[(int) RID_VOLATILE] : NULL_TREE,
6590 string, outputs, inputs, clobbers));
6594 /* Generate the ASM_OPERANDS insn;
6595 store into the TREE_VALUEs of OUTPUTS some trees for
6596 where the values were actually stored. */
6597 expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line);
6599 /* Copy all the intermediate outputs into the specified outputs. */
6600 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6602 if (o[i] != TREE_VALUE (tail))
6604 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
6605 NULL_RTX, VOIDmode, EXPAND_NORMAL);
6608 /* Restore the original value so that it's correct the next
6609 time we expand this function. */
6610 TREE_VALUE (tail) = o[i];
6612 /* Detect modification of read-only values.
6613 (Otherwise done by build_modify_expr.) */
6616 tree type = TREE_TYPE (o[i]);
6617 if (TREE_READONLY (o[i])
6618 || TYPE_READONLY (type)
6619 || ((TREE_CODE (type) == RECORD_TYPE
6620 || TREE_CODE (type) == UNION_TYPE)
6621 && C_TYPE_FIELDS_READONLY (type)))
6622 readonly_warning (o[i], "modification by `asm'");
6626 /* Those MODIFY_EXPRs could do autoincrements. */
6630 /* Expand a C `return' statement.
6631 RETVAL is the expression for what to return,
6632 or a null pointer for `return;' with no value. */
6635 c_expand_return (retval)
6638 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6640 if (TREE_THIS_VOLATILE (current_function_decl))
6641 warning ("function declared `noreturn' has a `return' statement");
6645 current_function_returns_null = 1;
6646 if ((warn_return_type || flag_isoc99)
6647 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6648 pedwarn_c99 ("`return' with no value, in function returning non-void");
6650 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6652 current_function_returns_null = 1;
6653 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6654 pedwarn ("`return' with a value, in function returning void");
6658 tree t = convert_for_assignment (valtype, retval, _("return"),
6659 NULL_TREE, NULL_TREE, 0);
6660 tree res = DECL_RESULT (current_function_decl);
6663 if (t == error_mark_node)
6666 inner = t = convert (TREE_TYPE (res), t);
6668 /* Strip any conversions, additions, and subtractions, and see if
6669 we are returning the address of a local variable. Warn if so. */
6672 switch (TREE_CODE (inner))
6674 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6676 inner = TREE_OPERAND (inner, 0);
6680 /* If the second operand of the MINUS_EXPR has a pointer
6681 type (or is converted from it), this may be valid, so
6682 don't give a warning. */
6684 tree op1 = TREE_OPERAND (inner, 1);
6686 while (! POINTER_TYPE_P (TREE_TYPE (op1))
6687 && (TREE_CODE (op1) == NOP_EXPR
6688 || TREE_CODE (op1) == NON_LVALUE_EXPR
6689 || TREE_CODE (op1) == CONVERT_EXPR))
6690 op1 = TREE_OPERAND (op1, 0);
6692 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6695 inner = TREE_OPERAND (inner, 0);
6700 inner = TREE_OPERAND (inner, 0);
6702 while (TREE_CODE_CLASS (TREE_CODE (inner)) == 'r')
6703 inner = TREE_OPERAND (inner, 0);
6705 if (TREE_CODE (inner) == VAR_DECL
6706 && ! DECL_EXTERNAL (inner)
6707 && ! TREE_STATIC (inner)
6708 && DECL_CONTEXT (inner) == current_function_decl)
6709 warning ("function returns address of local variable");
6719 retval = build (MODIFY_EXPR, TREE_TYPE (res), res, t);
6720 current_function_returns_value = 1;
6723 add_stmt (build_return_stmt (retval));
6727 /* The SWITCH_STMT being built. */
6729 /* A splay-tree mapping the low element of a case range to the high
6730 element, or NULL_TREE if there is no high element. Used to
6731 determine whether or not a new case label duplicates an old case
6732 label. We need a tree, rather than simply a hash table, because
6733 of the GNU case range extension. */
6735 /* The next node on the stack. */
6736 struct c_switch *next;
6739 /* A stack of the currently active switch statements. The innermost
6740 switch statement is on the top of the stack. There is no need to
6741 mark the stack for garbage collection because it is only active
6742 during the processing of the body of a function, and we never
6743 collect at that point. */
6745 static struct c_switch *switch_stack;
6747 /* Start a C switch statement, testing expression EXP. Return the new
6754 register enum tree_code code;
6756 struct c_switch *cs;
6758 if (exp != error_mark_node)
6760 code = TREE_CODE (TREE_TYPE (exp));
6761 type = TREE_TYPE (exp);
6763 if (code != INTEGER_TYPE
6764 && code != ENUMERAL_TYPE
6765 && code != ERROR_MARK)
6767 error ("switch quantity not an integer");
6768 exp = integer_zero_node;
6773 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6775 if (warn_traditional && !in_system_header
6776 && (type == long_integer_type_node
6777 || type == long_unsigned_type_node))
6778 warning ("`long' switch expression not converted to `int' in ISO C");
6780 exp = default_conversion (exp);
6781 type = TREE_TYPE (exp);
6782 index = get_unwidened (exp, NULL_TREE);
6783 /* We can't strip a conversion from a signed type to an
6784 unsigned, because if we did, int_fits_type_p would do the
6785 wrong thing when checking case values for being in range,
6786 and it's too hard to do the right thing. */
6787 if (TREE_UNSIGNED (TREE_TYPE (exp))
6788 == TREE_UNSIGNED (TREE_TYPE (index)))
6793 /* Add this new SWITCH_STMT to the stack. */
6794 cs = (struct c_switch *) xmalloc (sizeof (*cs));
6795 cs->switch_stmt = build_stmt (SWITCH_STMT, exp, NULL_TREE, NULL_TREE);
6796 cs->cases = splay_tree_new (case_compare, NULL, NULL);
6797 cs->next = switch_stack;
6800 return add_stmt (switch_stack->switch_stmt);
6803 /* Process a case label. */
6806 do_case (low_value, high_value)
6811 c_add_case_label (switch_stack->cases,
6812 SWITCH_COND (switch_stack->switch_stmt),
6816 error ("case label not within a switch statement");
6818 error ("`default' label not within a switch statement");
6821 /* Finish the switch statement. */
6826 struct c_switch *cs = switch_stack;
6828 RECHAIN_STMTS (cs->switch_stmt, SWITCH_BODY (cs->switch_stmt));
6830 /* Pop the stack. */
6831 switch_stack = switch_stack->next;
6832 splay_tree_delete (cs->cases);