1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
21 /* This file is part of the C front end.
22 It contains routines to build C expressions given their operands,
23 including computing the types of the result, C-specific error checks,
24 and some optimization.
26 There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
27 and to process initializations in declarations (since they work
28 like a strange sort of assignment). */
36 /* Nonzero if we've already printed a "partly bracketed initializer"
37 message within this initializer. */
38 static int partial_bracket_mentioned = 0;
40 extern char *index ();
41 extern char *rindex ();
43 int mark_addressable ();
44 static tree convert_for_assignment ();
45 static void warn_for_assignment ();
46 static int function_types_compatible_p ();
47 static int type_lists_compatible_p ();
48 int self_promoting_args_p ();
49 static int self_promoting_type_p ();
50 static int comp_target_types ();
51 static tree pointer_int_sum ();
52 static tree pointer_diff ();
53 static tree convert_sequence ();
54 static tree unary_complex_lvalue ();
55 static tree process_init_constructor ();
56 static tree convert_arguments ();
57 static char *get_spelling ();
58 static tree digest_init ();
59 static void pedantic_lvalue_warning ();
60 tree truthvalue_conversion ();
61 void incomplete_type_error ();
62 void readonly_warning ();
63 static tree internal_build_compound_expr ();
65 void process_init_element ();
67 /* Do `exp = require_complete_type (exp);' to make sure exp
68 does not have an incomplete type. (That includes void types.) */
71 require_complete_type (value)
74 tree type = TREE_TYPE (value);
76 /* First, detect a valid value with a complete type. */
77 if (TYPE_SIZE (type) != 0
78 && type != void_type_node)
81 incomplete_type_error (value, type);
82 return error_mark_node;
85 /* Print an error message for invalid use of an incomplete type.
86 VALUE is the expression that was used (or 0 if that isn't known)
87 and TYPE is the type that was invalid. */
90 incomplete_type_error (value, type)
96 /* Avoid duplicate error message. */
97 if (TREE_CODE (type) == ERROR_MARK)
100 if (value != 0 && (TREE_CODE (value) == VAR_DECL
101 || TREE_CODE (value) == PARM_DECL))
102 error ("`%s' has an incomplete type",
103 IDENTIFIER_POINTER (DECL_NAME (value)));
107 /* We must print an error message. Be clever about what it says. */
109 switch (TREE_CODE (type))
112 errmsg = "invalid use of undefined type `struct %s'";
116 errmsg = "invalid use of undefined type `union %s'";
120 errmsg = "invalid use of undefined type `enum %s'";
124 error ("invalid use of void expression");
128 if (TYPE_DOMAIN (type))
130 type = TREE_TYPE (type);
133 error ("invalid use of array with unspecified bounds");
140 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
141 error (errmsg, IDENTIFIER_POINTER (TYPE_NAME (type)));
143 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
144 error ("invalid use of incomplete typedef `%s'",
145 IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
149 /* Return a variant of TYPE which has all the type qualifiers of LIKE
150 as well as those of TYPE. */
153 qualify_type (type, like)
156 int constflag = TYPE_READONLY (type) || TYPE_READONLY (like);
157 int volflag = TYPE_VOLATILE (type) || TYPE_VOLATILE (like);
158 return c_build_type_variant (type, constflag, volflag);
161 /* Return the common type of two types.
162 We assume that comptypes has already been done and returned 1;
163 if that isn't so, this may crash. In particular, we assume that qualifiers
166 This is the type for the result of most arithmetic operations
167 if the operands have the given two types. */
173 register enum tree_code code1;
174 register enum tree_code code2;
176 /* Save time if the two types are the same. */
178 if (t1 == t2) return t1;
180 /* If one type is nonsense, use the other. */
181 if (t1 == error_mark_node)
183 if (t2 == error_mark_node)
186 /* Treat an enum type as the unsigned integer type of the same width. */
188 if (TREE_CODE (t1) == ENUMERAL_TYPE)
189 t1 = type_for_size (TYPE_PRECISION (t1), 1);
190 if (TREE_CODE (t2) == ENUMERAL_TYPE)
191 t2 = type_for_size (TYPE_PRECISION (t2), 1);
193 code1 = TREE_CODE (t1);
194 code2 = TREE_CODE (t2);
196 /* If one type is complex, form the common type
197 of the non-complex components,
198 then make that complex. */
199 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
201 tree subtype1, subtype2, subtype;
202 if (code1 == COMPLEX_TYPE)
203 subtype1 = TREE_TYPE (t1);
206 if (code2 == COMPLEX_TYPE)
207 subtype2 = TREE_TYPE (t2);
210 subtype = common_type (subtype1, subtype2);
211 return build_complex_type (subtype);
218 /* If only one is real, use it as the result. */
220 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
223 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
226 /* Both real or both integers; use the one with greater precision. */
228 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
230 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
233 /* Same precision. Prefer longs to ints even when same size. */
235 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
236 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
237 return long_unsigned_type_node;
239 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
240 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
242 /* But preserve unsignedness from the other type,
243 since long cannot hold all the values of an unsigned int. */
244 if (TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
245 return long_unsigned_type_node;
246 return long_integer_type_node;
249 /* Otherwise prefer the unsigned one. */
251 if (TREE_UNSIGNED (t1))
256 /* For two pointers, do this recursively on the target type,
257 and combine the qualifiers of the two types' targets. */
258 /* This code was turned off; I don't know why.
259 But ANSI C specifies doing this with the qualifiers.
260 So I turned it on again. */
262 tree target = common_type (TYPE_MAIN_VARIANT (TREE_TYPE (t1)),
263 TYPE_MAIN_VARIANT (TREE_TYPE (t2)));
265 = TYPE_READONLY (TREE_TYPE (t1)) || TYPE_READONLY (TREE_TYPE (t2));
267 = TYPE_VOLATILE (TREE_TYPE (t1)) || TYPE_VOLATILE (TREE_TYPE (t2));
268 return build_pointer_type (c_build_type_variant (target, constp, volatilep));
271 return build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2)));
276 tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
277 /* Save space: see if the result is identical to one of the args. */
278 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
280 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
282 /* Merge the element types, and have a size if either arg has one. */
283 return build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
287 /* Function types: prefer the one that specified arg types.
288 If both do, merge the arg types. Also merge the return types. */
290 tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
291 tree p1 = TYPE_ARG_TYPES (t1);
292 tree p2 = TYPE_ARG_TYPES (t2);
297 /* Save space: see if the result is identical to one of the args. */
298 if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2))
300 if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1))
303 /* Simple way if one arg fails to specify argument types. */
304 if (TYPE_ARG_TYPES (t1) == 0)
305 return build_function_type (valtype, TYPE_ARG_TYPES (t2));
306 if (TYPE_ARG_TYPES (t2) == 0)
307 return build_function_type (valtype, TYPE_ARG_TYPES (t1));
309 /* If both args specify argument types, we must merge the two
310 lists, argument by argument. */
312 len = list_length (p1);
315 for (i = 0; i < len; i++)
316 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
321 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
323 /* A null type means arg type is not specified.
324 Take whatever the other function type has. */
325 if (TREE_VALUE (p1) == 0)
327 TREE_VALUE (n) = TREE_VALUE (p2);
330 if (TREE_VALUE (p2) == 0)
332 TREE_VALUE (n) = TREE_VALUE (p1);
336 /* Given wait (union {union wait *u; int *i} *)
337 and wait (union wait *),
338 prefer union wait * as type of parm. */
339 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
340 && TREE_VALUE (p1) != TREE_VALUE (p2))
343 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
344 memb; memb = TREE_CHAIN (memb))
345 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2)))
347 TREE_VALUE (n) = TREE_VALUE (p2);
349 pedwarn ("function types not truly compatible in ANSI C");
353 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
354 && TREE_VALUE (p2) != TREE_VALUE (p1))
357 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
358 memb; memb = TREE_CHAIN (memb))
359 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1)))
361 TREE_VALUE (n) = TREE_VALUE (p1);
363 pedwarn ("function types not truly compatible in ANSI C");
367 TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2));
371 return build_function_type (valtype, newargs);
380 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
381 or various other operations. Return 2 if they are compatible
382 but a warning may be needed if you use them together. */
385 comptypes (type1, type2)
388 register tree t1 = type1;
389 register tree t2 = type2;
391 /* Suppress errors caused by previously reported errors. */
393 if (t1 == t2 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
396 /* Treat an enum type as the unsigned integer type of the same width. */
398 if (TREE_CODE (t1) == ENUMERAL_TYPE)
399 t1 = type_for_size (TYPE_PRECISION (t1), 1);
400 if (TREE_CODE (t2) == ENUMERAL_TYPE)
401 t2 = type_for_size (TYPE_PRECISION (t2), 1);
406 /* Different classes of types can't be compatible. */
408 if (TREE_CODE (t1) != TREE_CODE (t2)) return 0;
410 /* Qualifiers must match. */
412 if (TYPE_READONLY (t1) != TYPE_READONLY (t2))
414 if (TYPE_VOLATILE (t1) != TYPE_VOLATILE (t2))
417 /* Allow for two different type nodes which have essentially the same
418 definition. Note that we already checked for equality of the type
419 type qualifiers (just above). */
421 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
424 switch (TREE_CODE (t1))
427 return (TREE_TYPE (t1) == TREE_TYPE (t2)
428 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
431 return function_types_compatible_p (t1, t2);
435 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
437 tree d1 = TYPE_DOMAIN (t1);
438 tree d2 = TYPE_DOMAIN (t2);
440 /* Target types must match incl. qualifiers. */
441 if (TREE_TYPE (t1) != TREE_TYPE (t2)
442 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
445 /* Sizes must match unless one is missing or variable. */
446 if (d1 == 0 || d2 == 0 || d1 == d2
447 || TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
448 || TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
449 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST
450 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)
453 return (((TREE_INT_CST_LOW (TYPE_MIN_VALUE (d1))
454 == TREE_INT_CST_LOW (TYPE_MIN_VALUE (d2)))
455 && (TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d1))
456 == TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d2)))
457 && (TREE_INT_CST_LOW (TYPE_MAX_VALUE (d1))
458 == TREE_INT_CST_LOW (TYPE_MAX_VALUE (d2)))
459 && (TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d1))
460 == TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d2))))
465 if (maybe_objc_comptypes (t1, t2, 0) == 1)
471 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
472 ignoring their qualifiers. */
475 comp_target_types (ttl, ttr)
480 /* Give maybe_objc_comptypes a crack at letting these types through. */
481 if (val = maybe_objc_comptypes (ttl, ttr, 1) >= 0)
484 val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)),
485 TYPE_MAIN_VARIANT (TREE_TYPE (ttr)));
487 if (val == 2 && pedantic)
488 pedwarn ("types are not quite compatible");
492 /* Subroutines of `comptypes'. */
494 /* Return 1 if two function types F1 and F2 are compatible.
495 If either type specifies no argument types,
496 the other must specify a fixed number of self-promoting arg types.
497 Otherwise, if one type specifies only the number of arguments,
498 the other must specify that number of self-promoting arg types.
499 Otherwise, the argument types must match. */
502 function_types_compatible_p (f1, f2)
506 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
510 if (!(TREE_TYPE (f1) == TREE_TYPE (f2)
511 || (val = comptypes (TREE_TYPE (f1), TREE_TYPE (f2)))))
514 args1 = TYPE_ARG_TYPES (f1);
515 args2 = TYPE_ARG_TYPES (f2);
517 /* An unspecified parmlist matches any specified parmlist
518 whose argument types don't need default promotions. */
522 if (!self_promoting_args_p (args2))
524 /* If one of these types comes from a non-prototype fn definition,
525 compare that with the other type's arglist.
526 If they don't match, ask for a warning (but no error). */
527 if (TYPE_ACTUAL_ARG_TYPES (f1)
528 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
534 if (!self_promoting_args_p (args1))
536 if (TYPE_ACTUAL_ARG_TYPES (f2)
537 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
542 /* Both types have argument lists: compare them and propagate results. */
543 val1 = type_lists_compatible_p (args1, args2);
544 return val1 != 1 ? val1 : val;
547 /* Check two lists of types for compatibility,
548 returning 0 for incompatible, 1 for compatible,
549 or 2 for compatible with warning. */
552 type_lists_compatible_p (args1, args2)
555 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
561 if (args1 == 0 && args2 == 0)
563 /* If one list is shorter than the other,
564 they fail to match. */
565 if (args1 == 0 || args2 == 0)
567 /* A null pointer instead of a type
568 means there is supposed to be an argument
569 but nothing is specified about what type it has.
570 So match anything that self-promotes. */
571 if (TREE_VALUE (args1) == 0)
573 if (! self_promoting_type_p (TREE_VALUE (args2)))
576 else if (TREE_VALUE (args2) == 0)
578 if (! self_promoting_type_p (TREE_VALUE (args1)))
581 else if (! (newval = comptypes (TREE_VALUE (args1), TREE_VALUE (args2))))
583 /* Allow wait (union {union wait *u; int *i} *)
584 and wait (union wait *) to be compatible. */
585 if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE
586 && TYPE_NAME (TREE_VALUE (args1)) == 0
587 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST
588 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)),
589 TYPE_SIZE (TREE_VALUE (args2))))
592 for (memb = TYPE_FIELDS (TREE_VALUE (args1));
593 memb; memb = TREE_CHAIN (memb))
594 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2)))
599 else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE
600 && TYPE_NAME (TREE_VALUE (args2)) == 0
601 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST
602 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)),
603 TYPE_SIZE (TREE_VALUE (args1))))
606 for (memb = TYPE_FIELDS (TREE_VALUE (args2));
607 memb; memb = TREE_CHAIN (memb))
608 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1)))
617 /* comptypes said ok, but record if it said to warn. */
621 args1 = TREE_CHAIN (args1);
622 args2 = TREE_CHAIN (args2);
626 /* Return 1 if PARMS specifies a fixed number of parameters
627 and none of their types is affected by default promotions. */
630 self_promoting_args_p (parms)
634 for (t = parms; t; t = TREE_CHAIN (t))
636 register tree type = TREE_VALUE (t);
638 if (TREE_CHAIN (t) == 0 && type != void_type_node)
644 if (TYPE_MAIN_VARIANT (type) == float_type_node)
647 if (C_PROMOTING_INTEGER_TYPE_P (type))
653 /* Return 1 if TYPE is not affected by default promotions. */
656 self_promoting_type_p (type)
659 if (TYPE_MAIN_VARIANT (type) == float_type_node)
662 if (C_PROMOTING_INTEGER_TYPE_P (type))
668 /* Return an unsigned type the same as TYPE in other respects. */
674 tree type1 = TYPE_MAIN_VARIANT (type);
675 if (type1 == signed_char_type_node || type1 == char_type_node)
676 return unsigned_char_type_node;
677 if (type1 == integer_type_node)
678 return unsigned_type_node;
679 if (type1 == short_integer_type_node)
680 return short_unsigned_type_node;
681 if (type1 == long_integer_type_node)
682 return long_unsigned_type_node;
683 if (type1 == long_long_integer_type_node)
684 return long_long_unsigned_type_node;
688 /* Return a signed type the same as TYPE in other respects. */
694 tree type1 = TYPE_MAIN_VARIANT (type);
695 if (type1 == unsigned_char_type_node || type1 == char_type_node)
696 return signed_char_type_node;
697 if (type1 == unsigned_type_node)
698 return integer_type_node;
699 if (type1 == short_unsigned_type_node)
700 return short_integer_type_node;
701 if (type1 == long_unsigned_type_node)
702 return long_integer_type_node;
703 if (type1 == long_long_unsigned_type_node)
704 return long_long_integer_type_node;
708 /* Return a type the same as TYPE except unsigned or
709 signed according to UNSIGNEDP. */
712 signed_or_unsigned_type (unsignedp, type)
716 if (TREE_CODE (type) != INTEGER_TYPE)
718 if (TYPE_PRECISION (type) == TYPE_PRECISION (signed_char_type_node))
719 return unsignedp ? unsigned_char_type_node : signed_char_type_node;
720 if (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
721 return unsignedp ? unsigned_type_node : integer_type_node;
722 if (TYPE_PRECISION (type) == TYPE_PRECISION (short_integer_type_node))
723 return unsignedp ? short_unsigned_type_node : short_integer_type_node;
724 if (TYPE_PRECISION (type) == TYPE_PRECISION (long_integer_type_node))
725 return unsignedp ? long_unsigned_type_node : long_integer_type_node;
726 if (TYPE_PRECISION (type) == TYPE_PRECISION (long_long_integer_type_node))
727 return (unsignedp ? long_long_unsigned_type_node
728 : long_long_integer_type_node);
732 /* Compute the value of the `sizeof' operator. */
738 enum tree_code code = TREE_CODE (type);
741 if (code == FUNCTION_TYPE)
743 if (pedantic || warn_pointer_arith)
744 pedwarn ("sizeof applied to a function type");
747 if (code == VOID_TYPE)
749 if (pedantic || warn_pointer_arith)
750 pedwarn ("sizeof applied to a void type");
753 if (code == ERROR_MARK)
755 if (TYPE_SIZE (type) == 0)
757 error ("sizeof applied to an incomplete type");
761 /* Convert in case a char is more than one unit. */
762 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
763 size_int (TYPE_PRECISION (char_type_node)));
764 /* size_binop does not put the constant in range, so do it now. */
765 if (TREE_CODE (t) == INTEGER_CST && force_fit_type (t, 0))
766 TREE_CONSTANT_OVERFLOW (t) = TREE_OVERFLOW (t) = 1;
771 c_sizeof_nowarn (type)
774 enum tree_code code = TREE_CODE (type);
777 if (code == FUNCTION_TYPE
779 || code == ERROR_MARK)
781 if (TYPE_SIZE (type) == 0)
784 /* Convert in case a char is more than one unit. */
785 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
786 size_int (TYPE_PRECISION (char_type_node)));
787 force_fit_type (t, 0);
791 /* Compute the size to increment a pointer by. */
794 c_size_in_bytes (type)
797 enum tree_code code = TREE_CODE (type);
800 if (code == FUNCTION_TYPE)
802 if (code == VOID_TYPE)
804 if (code == ERROR_MARK)
806 if (TYPE_SIZE (type) == 0)
808 error ("arithmetic on pointer to an incomplete type");
812 /* Convert in case a char is more than one unit. */
813 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
814 size_int (BITS_PER_UNIT));
815 force_fit_type (t, 0);
819 /* Implement the __alignof keyword: Return the minimum required
820 alignment of TYPE, measured in bytes. */
826 enum tree_code code = TREE_CODE (type);
828 if (code == FUNCTION_TYPE)
829 return size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
831 if (code == VOID_TYPE || code == ERROR_MARK)
834 return size_int (TYPE_ALIGN (type) / BITS_PER_UNIT);
837 /* Implement the __alignof keyword: Return the minimum required
838 alignment of EXPR, measured in bytes. For VAR_DECL's and
839 FIELD_DECL's return DECL_ALIGN (which can be set from an
840 "aligned" __attribute__ specification). */
843 c_alignof_expr (expr)
846 if (TREE_CODE (expr) == VAR_DECL)
847 return size_int (DECL_ALIGN (expr) / BITS_PER_UNIT);
849 if (TREE_CODE (expr) == COMPONENT_REF
850 && DECL_BIT_FIELD (TREE_OPERAND (expr, 1)))
852 error ("`__alignof' applied to a bit-field");
855 else if (TREE_CODE (expr) == COMPONENT_REF
856 && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
857 return size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT);
859 if (TREE_CODE (expr) == INDIRECT_REF)
861 tree t = TREE_OPERAND (expr, 0);
863 int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
865 while (TREE_CODE (t) == NOP_EXPR
866 && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
870 t = TREE_OPERAND (t, 0);
871 thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
872 if (thisalign > bestalign)
873 best = t, bestalign = thisalign;
875 return c_alignof (TREE_TYPE (TREE_TYPE (best)));
878 return c_alignof (TREE_TYPE (expr));
880 /* Return either DECL or its known constant value (if it has one). */
883 decl_constant_value (decl)
886 if (! TREE_PUBLIC (decl)
887 /* Don't change a variable array bound or initial value to a constant
888 in a place where a variable is invalid. */
889 && current_function_decl != 0
891 && ! TREE_THIS_VOLATILE (decl)
892 && DECL_INITIAL (decl) != 0
893 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
894 /* This is invalid if initial value is not constant.
895 If it has either a function call, a memory reference,
896 or a variable, then re-evaluating it could give different results. */
897 && TREE_CONSTANT (DECL_INITIAL (decl))
898 /* Check for cases where this is sub-optimal, even though valid. */
899 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR
900 && DECL_MODE (decl) != BLKmode)
901 return DECL_INITIAL (decl);
905 /* Perform default promotions for C data used in expressions.
906 Arrays and functions are converted to pointers;
907 enumeral types or short or char, to int.
908 In addition, manifest constants symbols are replaced by their values. */
911 default_conversion (exp)
914 register tree type = TREE_TYPE (exp);
915 register enum tree_code code = TREE_CODE (type);
917 /* Constants can be used directly unless they're not loadable. */
918 if (TREE_CODE (exp) == CONST_DECL)
919 exp = DECL_INITIAL (exp);
920 /* Replace a nonvolatile const static variable with its value. */
922 && TREE_CODE (exp) == VAR_DECL
923 && TREE_READONLY (exp)
924 /* But not for iterators! */
926 && DECL_MODE (exp) != BLKmode)
928 exp = decl_constant_value (exp);
929 type = TREE_TYPE (exp);
932 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
934 /* Do not use STRIP_NOPS here! It will remove conversions from pointer
935 to integer and cause infinite recursion. */
936 while (TREE_CODE (exp) == NON_LVALUE_EXPR
937 || (TREE_CODE (exp) == NOP_EXPR
938 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
939 exp = TREE_OPERAND (exp, 0);
941 /* Normally convert enums to int,
942 but convert wide enums to something wider. */
943 if (code == ENUMERAL_TYPE)
945 type = type_for_size (MAX (TYPE_PRECISION (type),
946 TYPE_PRECISION (integer_type_node)),
948 || TYPE_PRECISION (type) >= TYPE_PRECISION (integer_type_node))
949 && TREE_UNSIGNED (type)));
950 return convert (type, exp);
953 if (C_PROMOTING_INTEGER_TYPE_P (type))
955 /* Traditionally, unsignedness is preserved in default promotions.
956 Also preserve unsignedness if not really getting any wider. */
957 if (TREE_UNSIGNED (type)
959 || TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
960 return convert (unsigned_type_node, exp);
961 return convert (integer_type_node, exp);
963 if (flag_traditional && !flag_allow_single_precision
964 && TYPE_MAIN_VARIANT (type) == float_type_node)
965 return convert (double_type_node, exp);
966 if (code == VOID_TYPE)
968 error ("void value not ignored as it ought to be");
969 return error_mark_node;
971 if (code == FUNCTION_TYPE)
973 return build_unary_op (ADDR_EXPR, exp, 0);
975 if (code == ARRAY_TYPE)
978 tree restype = TREE_TYPE (type);
983 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r'
984 || TREE_CODE_CLASS (TREE_CODE (exp)) == 'd')
986 constp = TREE_READONLY (exp);
987 volatilep = TREE_THIS_VOLATILE (exp);
990 if (TYPE_READONLY (type) || TYPE_VOLATILE (type)
991 || constp || volatilep)
992 restype = c_build_type_variant (restype,
993 TYPE_READONLY (type) || constp,
994 TYPE_VOLATILE (type) || volatilep);
996 if (TREE_CODE (exp) == INDIRECT_REF)
997 return convert (TYPE_POINTER_TO (restype),
998 TREE_OPERAND (exp, 0));
1000 if (TREE_CODE (exp) == COMPOUND_EXPR)
1002 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
1003 return build (COMPOUND_EXPR, TREE_TYPE (op1),
1004 TREE_OPERAND (exp, 0), op1);
1008 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1010 error ("invalid use of non-lvalue array");
1011 return error_mark_node;
1014 ptrtype = build_pointer_type (restype);
1016 if (TREE_CODE (exp) == VAR_DECL)
1018 /* ??? This is not really quite correct
1019 in that the type of the operand of ADDR_EXPR
1020 is not the target type of the type of the ADDR_EXPR itself.
1021 Question is, can this lossage be avoided? */
1022 adr = build1 (ADDR_EXPR, ptrtype, exp);
1023 if (mark_addressable (exp) == 0)
1024 return error_mark_node;
1025 TREE_CONSTANT (adr) = staticp (exp);
1026 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1029 /* This way is better for a COMPONENT_REF since it can
1030 simplify the offset for a component. */
1031 adr = build_unary_op (ADDR_EXPR, exp, 1);
1032 return convert (ptrtype, adr);
1037 /* Look up component name in the structure type definition.
1039 If this component name is found indirectly within an anonymous union,
1040 store in *INDIRECT the component which directly contains
1041 that anonymous union. Otherwise, set *INDIRECT to 0. */
1044 lookup_field (type, component, indirect)
1045 tree type, component;
1050 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1051 to the field elements. Use a binary search on this array to quickly
1052 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1053 will always be set for structures which have many elements. */
1055 if (TYPE_LANG_SPECIFIC (type))
1058 tree *field_array = &TYPE_LANG_SPECIFIC (type)->elts[0];
1060 field = TYPE_FIELDS (type);
1062 top = TYPE_LANG_SPECIFIC (type)->len;
1063 while (top - bot > 1)
1067 half = (top - bot + 1) >> 1;
1068 field = field_array[bot+half];
1070 if (DECL_NAME (field) == NULL_TREE)
1072 /* Step through all anon unions in linear fashion. */
1073 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1077 field = field_array[bot++];
1078 anon = lookup_field (TREE_TYPE (field), component, &junk);
1079 if (anon != NULL_TREE)
1086 /* Entire record is only anon unions. */
1090 /* Restart the binary search, with new lower bound. */
1094 cmp = (HOST_WIDE_INT) DECL_NAME (field) - (HOST_WIDE_INT) component;
1103 if (DECL_NAME (field_array[bot]) == component)
1104 field = field_array[bot];
1105 else if (DECL_NAME (field) != component)
1110 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1112 if (DECL_NAME (field) == NULL_TREE)
1115 tree anon = lookup_field (TREE_TYPE (field), component, &junk);
1116 if (anon != NULL_TREE)
1123 if (DECL_NAME (field) == component)
1128 *indirect = NULL_TREE;
1132 /* Make an expression to refer to the COMPONENT field of
1133 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1136 build_component_ref (datum, component)
1137 tree datum, component;
1139 register tree type = TREE_TYPE (datum);
1140 register enum tree_code code = TREE_CODE (type);
1141 register tree field = NULL;
1144 /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it
1145 unless we are not to support things not strictly ANSI. */
1146 switch (TREE_CODE (datum))
1150 tree value = build_component_ref (TREE_OPERAND (datum, 1), component);
1151 return build (COMPOUND_EXPR, TREE_TYPE (value),
1152 TREE_OPERAND (datum, 0), value);
1155 return build_conditional_expr
1156 (TREE_OPERAND (datum, 0),
1157 build_component_ref (TREE_OPERAND (datum, 1), component),
1158 build_component_ref (TREE_OPERAND (datum, 2), component));
1161 /* See if there is a field or component with name COMPONENT. */
1163 if (code == RECORD_TYPE || code == UNION_TYPE)
1167 if (TYPE_SIZE (type) == 0)
1169 incomplete_type_error (NULL_TREE, type);
1170 return error_mark_node;
1173 field = lookup_field (type, component, &indirect);
1177 error (code == RECORD_TYPE
1178 ? "structure has no member named `%s'"
1179 : "union has no member named `%s'",
1180 IDENTIFIER_POINTER (component));
1181 return error_mark_node;
1183 if (TREE_TYPE (field) == error_mark_node)
1184 return error_mark_node;
1186 /* If FIELD was found buried within an anonymous union,
1187 make one COMPONENT_REF to get that anonymous union,
1188 then fall thru to make a second COMPONENT_REF to get FIELD. */
1191 ref = build (COMPONENT_REF, TREE_TYPE (indirect), datum, indirect);
1192 if (TREE_READONLY (datum) || TREE_READONLY (indirect))
1193 TREE_READONLY (ref) = 1;
1194 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (indirect))
1195 TREE_THIS_VOLATILE (ref) = 1;
1199 ref = build (COMPONENT_REF, TREE_TYPE (field), datum, field);
1201 if (TREE_READONLY (datum) || TREE_READONLY (field))
1202 TREE_READONLY (ref) = 1;
1203 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (field))
1204 TREE_THIS_VOLATILE (ref) = 1;
1208 else if (code != ERROR_MARK)
1209 error ("request for member `%s' in something not a structure or union",
1210 IDENTIFIER_POINTER (component));
1212 return error_mark_node;
1215 /* Given an expression PTR for a pointer, return an expression
1216 for the value pointed to.
1217 ERRORSTRING is the name of the operator to appear in error messages. */
1220 build_indirect_ref (ptr, errorstring)
1224 register tree pointer = default_conversion (ptr);
1225 register tree type = TREE_TYPE (pointer);
1227 if (TREE_CODE (type) == POINTER_TYPE)
1229 if (TREE_CODE (pointer) == ADDR_EXPR
1231 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1232 == TREE_TYPE (type)))
1233 return TREE_OPERAND (pointer, 0);
1236 tree t = TREE_TYPE (type);
1237 register tree ref = build1 (INDIRECT_REF,
1238 TYPE_MAIN_VARIANT (t), pointer);
1240 if (TYPE_SIZE (t) == 0 && TREE_CODE (t) != ARRAY_TYPE)
1242 error ("dereferencing pointer to incomplete type");
1243 return error_mark_node;
1245 if (TREE_CODE (t) == VOID_TYPE)
1246 warning ("dereferencing `void *' pointer");
1248 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1249 so that we get the proper error message if the result is used
1250 to assign to. Also, &* is supposed to be a no-op.
1251 And ANSI C seems to specify that the type of the result
1252 should be the const type. */
1253 /* A de-reference of a pointer to const is not a const. It is valid
1254 to change it via some other pointer. */
1255 TREE_READONLY (ref) = TYPE_READONLY (t);
1256 TREE_SIDE_EFFECTS (ref)
1257 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer) || flag_volatile;
1258 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1262 else if (TREE_CODE (pointer) != ERROR_MARK)
1263 error ("invalid type argument of `%s'", errorstring);
1264 return error_mark_node;
1267 /* This handles expressions of the form "a[i]", which denotes
1270 This is logically equivalent in C to *(a+i), but we may do it differently.
1271 If A is a variable or a member, we generate a primitive ARRAY_REF.
1272 This avoids forcing the array out of registers, and can work on
1273 arrays that are not lvalues (for example, members of structures returned
1277 build_array_ref (array, index)
1282 error ("subscript missing in array reference");
1283 return error_mark_node;
1286 if (TREE_TYPE (array) == error_mark_node
1287 || TREE_TYPE (index) == error_mark_node)
1288 return error_mark_node;
1290 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
1291 && TREE_CODE (array) != INDIRECT_REF)
1295 /* Subscripting with type char is likely to lose
1296 on a machine where chars are signed.
1297 So warn on any machine, but optionally.
1298 Don't warn for unsigned char since that type is safe.
1299 Don't warn for signed char because anyone who uses that
1300 must have done so deliberately. */
1301 if (warn_char_subscripts
1302 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1303 warning ("array subscript has type `char'");
1305 /* Apply default promotions *after* noticing character types. */
1306 index = default_conversion (index);
1308 /* Require integer *after* promotion, for sake of enums. */
1309 if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE)
1311 error ("array subscript is not an integer");
1312 return error_mark_node;
1315 /* An array that is indexed by a non-constant
1316 cannot be stored in a register; we must be able to do
1317 address arithmetic on its address.
1318 Likewise an array of elements of variable size. */
1319 if (TREE_CODE (index) != INTEGER_CST
1320 || (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))) != 0
1321 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1323 if (mark_addressable (array) == 0)
1324 return error_mark_node;
1326 /* An array that is indexed by a constant value which is not within
1327 the array bounds cannot be stored in a register either; because we
1328 would get a crash in store_bit_field/extract_bit_field when trying
1329 to access a non-existent part of the register. */
1330 if (TREE_CODE (index) == INTEGER_CST
1331 && TYPE_VALUES (TREE_TYPE (array))
1332 && ! int_fits_type_p (index, TYPE_VALUES (TREE_TYPE (array))))
1334 if (mark_addressable (array) == 0)
1335 return error_mark_node;
1338 if (pedantic && !lvalue_p (array))
1340 if (DECL_REGISTER (array))
1341 pedwarn ("ANSI C forbids subscripting `register' array");
1343 pedwarn ("ANSI C forbids subscripting non-lvalue array");
1349 while (TREE_CODE (foo) == COMPONENT_REF)
1350 foo = TREE_OPERAND (foo, 0);
1351 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
1352 pedwarn ("ANSI C forbids subscripting non-lvalue array");
1355 type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array)));
1356 rval = build (ARRAY_REF, type, array, index);
1357 /* Array ref is const/volatile if the array elements are
1358 or if the array is. */
1359 TREE_READONLY (rval)
1360 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1361 | TREE_READONLY (array));
1362 TREE_SIDE_EFFECTS (rval)
1363 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1364 | TREE_SIDE_EFFECTS (array));
1365 TREE_THIS_VOLATILE (rval)
1366 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1367 /* This was added by rms on 16 Nov 91.
1368 It fixes vol struct foo *a; a->elts[1]
1369 in an inline function.
1370 Hope it doesn't break something else. */
1371 | TREE_THIS_VOLATILE (array));
1372 return require_complete_type (fold (rval));
1376 tree ar = default_conversion (array);
1377 tree ind = default_conversion (index);
1379 /* Put the integer in IND to simplify error checking. */
1380 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
1387 if (ar == error_mark_node)
1390 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
1392 error ("subscripted value is neither array nor pointer");
1393 return error_mark_node;
1395 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
1397 error ("array subscript is not an integer");
1398 return error_mark_node;
1401 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0),
1406 /* Build a function call to function FUNCTION with parameters PARAMS.
1407 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1408 TREE_VALUE of each node is a parameter-expression.
1409 FUNCTION's data type may be a function type or a pointer-to-function. */
1412 build_function_call (function, params)
1413 tree function, params;
1415 register tree fntype, fundecl;
1416 register tree coerced_params;
1417 tree name = NULL_TREE, assembler_name = NULL_TREE;
1419 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1420 STRIP_TYPE_NOPS (function);
1422 /* Convert anything with function type to a pointer-to-function. */
1423 if (TREE_CODE (function) == FUNCTION_DECL)
1425 name = DECL_NAME (function);
1426 assembler_name = DECL_ASSEMBLER_NAME (function);
1428 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1429 (because calling an inline function does not mean the function
1430 needs to be separately compiled). */
1431 fntype = build_type_variant (TREE_TYPE (function),
1432 TREE_READONLY (function),
1433 TREE_THIS_VOLATILE (function));
1435 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
1438 function = default_conversion (function);
1440 fntype = TREE_TYPE (function);
1442 if (TREE_CODE (fntype) == ERROR_MARK)
1443 return error_mark_node;
1445 if (!(TREE_CODE (fntype) == POINTER_TYPE
1446 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
1448 error ("called object is not a function");
1449 return error_mark_node;
1452 /* fntype now gets the type of function pointed to. */
1453 fntype = TREE_TYPE (fntype);
1455 /* Convert the parameters to the types declared in the
1456 function prototype, or apply default promotions. */
1459 = convert_arguments (TYPE_ARG_TYPES (fntype), params, name, fundecl);
1461 /* Check for errors in format strings. */
1463 if (warn_format && (name || assembler_name))
1464 check_function_format (name, assembler_name, coerced_params);
1466 /* Recognize certain built-in functions so we can make tree-codes
1467 other than CALL_EXPR. We do this when it enables fold-const.c
1468 to do something useful. */
1470 if (TREE_CODE (function) == ADDR_EXPR
1471 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
1472 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
1473 switch (DECL_FUNCTION_CODE (TREE_OPERAND (function, 0)))
1478 if (coerced_params == 0)
1479 return integer_zero_node;
1480 return build_unary_op (ABS_EXPR, TREE_VALUE (coerced_params), 0);
1484 register tree result
1485 = build (CALL_EXPR, TREE_TYPE (fntype),
1486 function, coerced_params, NULL_TREE);
1488 TREE_SIDE_EFFECTS (result) = 1;
1489 if (TREE_TYPE (result) == void_type_node)
1491 return require_complete_type (result);
1495 /* Convert the argument expressions in the list VALUES
1496 to the types in the list TYPELIST. The result is a list of converted
1497 argument expressions.
1499 If TYPELIST is exhausted, or when an element has NULL as its type,
1500 perform the default conversions.
1502 PARMLIST is the chain of parm decls for the function being called.
1503 It may be 0, if that info is not available.
1504 It is used only for generating error messages.
1506 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1508 This is also where warnings about wrong number of args are generated.
1510 Both VALUES and the returned value are chains of TREE_LIST nodes
1511 with the elements of the list in the TREE_VALUE slots of those nodes. */
1514 convert_arguments (typelist, values, name, fundecl)
1515 tree typelist, values, name, fundecl;
1517 register tree typetail, valtail;
1518 register tree result = NULL;
1521 /* Scan the given expressions and types, producing individual
1522 converted arguments and pushing them on RESULT in reverse order. */
1524 for (valtail = values, typetail = typelist, parmnum = 0;
1526 valtail = TREE_CHAIN (valtail), parmnum++)
1528 register tree type = typetail ? TREE_VALUE (typetail) : 0;
1529 register tree val = TREE_VALUE (valtail);
1531 if (type == void_type_node)
1534 error ("too many arguments to function `%s'",
1535 IDENTIFIER_POINTER (name));
1537 error ("too many arguments to function");
1541 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1542 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1543 to convert automatically to a pointer. */
1544 if (TREE_CODE (val) == NON_LVALUE_EXPR)
1545 val = TREE_OPERAND (val, 0);
1547 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
1548 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE)
1549 val = default_conversion (val);
1551 val = require_complete_type (val);
1555 /* Formal parm type is specified by a function prototype. */
1558 if (TYPE_SIZE (type) == 0)
1560 error ("type of formal parameter %d is incomplete", parmnum + 1);
1567 #ifdef PROMOTE_PROTOTYPES
1568 /* Rather than truncating and then reextending,
1569 convert directly to int, if that's the type we will want. */
1570 if (! flag_traditional
1571 && (TREE_CODE (type) == INTEGER_TYPE
1572 || TREE_CODE (type) == ENUMERAL_TYPE)
1573 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
1574 type = integer_type_node;
1577 #if 0 /* This turns out not to win--there's no way to write a prototype
1578 for a function whose arg type is a union with no tag. */
1579 /* Nameless union automatically casts the types it contains. */
1580 if (TREE_CODE (type) == UNION_TYPE && TYPE_NAME (type) == 0)
1584 for (field = TYPE_FIELDS (type); field;
1585 field = TREE_CHAIN (field))
1586 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
1587 TYPE_MAIN_VARIANT (TREE_TYPE (val))))
1591 val = build1 (CONVERT_EXPR, type, val);
1595 /* Optionally warn about conversions that
1596 differ from the default conversions. */
1597 if (warn_conversion)
1599 int formal_prec = TYPE_PRECISION (type);
1601 if (TREE_CODE (type) != REAL_TYPE
1602 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1603 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1604 else if (TREE_CODE (type) == REAL_TYPE
1605 && TREE_CODE (TREE_TYPE (val)) != REAL_TYPE)
1606 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1607 else if (TREE_CODE (type) == REAL_TYPE
1608 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1610 /* Warn if any argument is passed as `float',
1611 since without a prototype it would be `double'. */
1612 if (formal_prec == TYPE_PRECISION (float_type_node))
1613 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1615 /* Detect integer changing in width or signedness. */
1616 else if ((TREE_CODE (type) == INTEGER_TYPE
1617 || TREE_CODE (type) == ENUMERAL_TYPE)
1618 && (TREE_CODE (TREE_TYPE (val)) == INTEGER_TYPE
1619 || TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE))
1621 tree would_have_been = default_conversion (val);
1622 tree type1 = TREE_TYPE (would_have_been);
1624 if (TREE_CODE (type) == ENUMERAL_TYPE
1625 && type == TREE_TYPE (val))
1626 /* No warning if function asks for enum
1627 and the actual arg is that enum type. */
1629 else if (formal_prec != TYPE_PRECISION (type1))
1630 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1631 else if (TREE_UNSIGNED (type) == TREE_UNSIGNED (type1))
1633 /* Don't complain if the formal parameter type
1634 is an enum, because we can't tell now whether
1635 the value was an enum--even the same enum. */
1636 else if (TREE_CODE (type) == ENUMERAL_TYPE)
1638 else if (TREE_CODE (val) == INTEGER_CST
1639 && int_fits_type_p (val, type))
1640 /* Change in signedness doesn't matter
1641 if a constant value is unaffected. */
1643 /* Likewise for a constant in a NOP_EXPR. */
1644 else if (TREE_CODE (val) == NOP_EXPR
1645 && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST
1646 && int_fits_type_p (TREE_OPERAND (val, 0), type))
1648 #if 0 /* We never get such tree structure here. */
1649 else if (TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE
1650 && int_fits_type_p (TYPE_MIN_VALUE (TREE_TYPE (val)), type)
1651 && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE (val)), type))
1652 /* Change in signedness doesn't matter
1653 if an enum value is unaffected. */
1656 /* If the value is extended from a narrower
1657 unsigned type, it doesn't matter whether we
1658 pass it as signed or unsigned; the value
1659 certainly is the same either way. */
1660 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
1661 && TREE_UNSIGNED (TREE_TYPE (val)))
1663 else if (TREE_UNSIGNED (type))
1664 warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1);
1666 warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1);
1670 parmval = convert_for_assignment (type, val,
1671 (char *)0, /* arg passing */
1672 fundecl, name, parmnum + 1);
1674 #ifdef PROMOTE_PROTOTYPES
1675 if ((TREE_CODE (type) == INTEGER_TYPE
1676 || TREE_CODE (type) == ENUMERAL_TYPE)
1677 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
1678 parmval = default_conversion (parmval);
1681 result = tree_cons (NULL_TREE, parmval, result);
1683 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
1684 && (TYPE_PRECISION (TREE_TYPE (val))
1685 < TYPE_PRECISION (double_type_node)))
1686 /* Convert `float' to `double'. */
1687 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
1689 /* Convert `short' and `char' to full-size `int'. */
1690 result = tree_cons (NULL_TREE, default_conversion (val), result);
1693 typetail = TREE_CHAIN (typetail);
1696 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
1699 error ("too few arguments to function `%s'",
1700 IDENTIFIER_POINTER (name));
1702 error ("too few arguments to function");
1705 return nreverse (result);
1708 /* This is the entry point used by the parser
1709 for binary operators in the input.
1710 In addition to constructing the expression,
1711 we check for operands that were written with other binary operators
1712 in a way that is likely to confuse the user. */
1715 parser_build_binary_op (code, arg1, arg2)
1716 enum tree_code code;
1719 tree result = build_binary_op (code, arg1, arg2, 1);
1722 char class1 = TREE_CODE_CLASS (TREE_CODE (arg1));
1723 char class2 = TREE_CODE_CLASS (TREE_CODE (arg2));
1724 enum tree_code code1 = ERROR_MARK;
1725 enum tree_code code2 = ERROR_MARK;
1727 if (class1 == 'e' || class1 == '1'
1728 || class1 == '2' || class1 == '<')
1729 code1 = C_EXP_ORIGINAL_CODE (arg1);
1730 if (class2 == 'e' || class2 == '1'
1731 || class2 == '2' || class2 == '<')
1732 code2 = C_EXP_ORIGINAL_CODE (arg2);
1734 /* Check for cases such as x+y<<z which users are likely
1735 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1736 is cleared to prevent these warnings. */
1737 if (warn_parentheses)
1739 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
1741 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1742 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1743 warning ("suggest parentheses around + or - inside shift");
1746 if (code == TRUTH_ORIF_EXPR)
1748 if (code1 == TRUTH_ANDIF_EXPR
1749 || code2 == TRUTH_ANDIF_EXPR)
1750 warning ("suggest parentheses around && within ||");
1753 if (code == BIT_IOR_EXPR)
1755 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
1756 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1757 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
1758 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1759 warning ("suggest parentheses around arithmetic in operand of |");
1762 if (code == BIT_XOR_EXPR)
1764 if (code1 == BIT_AND_EXPR
1765 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1766 || code2 == BIT_AND_EXPR
1767 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1768 warning ("suggest parentheses around arithmetic in operand of ^");
1771 if (code == BIT_AND_EXPR)
1773 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1774 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1775 warning ("suggest parentheses around + or - in operand of &");
1779 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1780 if (TREE_CODE_CLASS (code) == '<' && extra_warnings
1781 && (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<'))
1782 warning ("comparisons like X<=Y<=Z do not have their mathematical meaning");
1784 unsigned_conversion_warning (result, arg1);
1785 unsigned_conversion_warning (result, arg2);
1786 overflow_warning (result);
1788 class = TREE_CODE_CLASS (TREE_CODE (result));
1790 /* Record the code that was specified in the source,
1791 for the sake of warnings about confusing nesting. */
1792 if (class == 'e' || class == '1'
1793 || class == '2' || class == '<')
1794 C_SET_EXP_ORIGINAL_CODE (result, code);
1797 int flag = TREE_CONSTANT (result);
1798 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1799 so that convert_for_assignment wouldn't strip it.
1800 That way, we got warnings for things like p = (1 - 1).
1801 But it turns out we should not get those warnings. */
1802 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
1803 C_SET_EXP_ORIGINAL_CODE (result, code);
1804 TREE_CONSTANT (result) = flag;
1810 /* Build a binary-operation expression without default conversions.
1811 CODE is the kind of expression to build.
1812 This function differs from `build' in several ways:
1813 the data type of the result is computed and recorded in it,
1814 warnings are generated if arg data types are invalid,
1815 special handling for addition and subtraction of pointers is known,
1816 and some optimization is done (operations on narrow ints
1817 are done in the narrower type when that gives the same result).
1818 Constant folding is also done before the result is returned.
1820 Note that the operands will never have enumeral types, or function
1821 or array types, because either they will have the default conversions
1822 performed or they have both just been converted to some other type in which
1823 the arithmetic is to be done. */
1826 build_binary_op (code, orig_op0, orig_op1, convert_p)
1827 enum tree_code code;
1828 tree orig_op0, orig_op1;
1832 register enum tree_code code0, code1;
1835 /* Expression code to give to the expression when it is built.
1836 Normally this is CODE, which is what the caller asked for,
1837 but in some special cases we change it. */
1838 register enum tree_code resultcode = code;
1840 /* Data type in which the computation is to be performed.
1841 In the simplest cases this is the common type of the arguments. */
1842 register tree result_type = NULL;
1844 /* Nonzero means operands have already been type-converted
1845 in whatever way is necessary.
1846 Zero means they need to be converted to RESULT_TYPE. */
1849 /* Nonzero means after finally constructing the expression
1850 give it this type. Otherwise, give it type RESULT_TYPE. */
1851 tree final_type = 0;
1853 /* Nonzero if this is an operation like MIN or MAX which can
1854 safely be computed in short if both args are promoted shorts.
1855 Also implies COMMON.
1856 -1 indicates a bitwise operation; this makes a difference
1857 in the exact conditions for when it is safe to do the operation
1858 in a narrower mode. */
1861 /* Nonzero if this is a comparison operation;
1862 if both args are promoted shorts, compare the original shorts.
1863 Also implies COMMON. */
1864 int short_compare = 0;
1866 /* Nonzero if this is a right-shift operation, which can be computed on the
1867 original short and then promoted if the operand is a promoted short. */
1868 int short_shift = 0;
1870 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1875 op0 = default_conversion (orig_op0);
1876 op1 = default_conversion (orig_op1);
1884 type0 = TREE_TYPE (op0);
1885 type1 = TREE_TYPE (op1);
1887 /* The expression codes of the data types of the arguments tell us
1888 whether the arguments are integers, floating, pointers, etc. */
1889 code0 = TREE_CODE (type0);
1890 code1 = TREE_CODE (type1);
1892 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1893 STRIP_TYPE_NOPS (op0);
1894 STRIP_TYPE_NOPS (op1);
1896 /* If an error was already reported for one of the arguments,
1897 avoid reporting another error. */
1899 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
1900 return error_mark_node;
1905 /* Handle the pointer + int case. */
1906 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
1907 return pointer_int_sum (PLUS_EXPR, op0, op1);
1908 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
1909 return pointer_int_sum (PLUS_EXPR, op1, op0);
1915 /* Subtraction of two similar pointers.
1916 We must subtract them as integers, then divide by object size. */
1917 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
1918 && comp_target_types (type0, type1))
1919 return pointer_diff (op0, op1);
1920 /* Handle pointer minus int. Just like pointer plus int. */
1921 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
1922 return pointer_int_sum (MINUS_EXPR, op0, op1);
1931 case TRUNC_DIV_EXPR:
1933 case FLOOR_DIV_EXPR:
1934 case ROUND_DIV_EXPR:
1935 case EXACT_DIV_EXPR:
1936 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
1937 || code0 == COMPLEX_TYPE)
1938 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
1939 || code1 == COMPLEX_TYPE))
1941 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
1942 resultcode = RDIV_EXPR;
1944 /* When dividing two signed integers, you have to promote to int.
1945 E.g. (short) -32868 / (short) -1 doesn't fit in a short. */
1946 shorten = TREE_UNSIGNED (orig_op0);
1952 case BIT_ANDTC_EXPR:
1955 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
1957 /* If one operand is a constant, and the other is a short type
1958 that has been converted to an int,
1959 really do the work in the short type and then convert the
1960 result to int. If we are lucky, the constant will be 0 or 1
1961 in the short type, making the entire operation go away. */
1962 if (TREE_CODE (op0) == INTEGER_CST
1963 && TREE_CODE (op1) == NOP_EXPR
1964 && TYPE_PRECISION (type1) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))
1965 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0))))
1967 final_type = result_type;
1968 op1 = TREE_OPERAND (op1, 0);
1969 result_type = TREE_TYPE (op1);
1971 if (TREE_CODE (op1) == INTEGER_CST
1972 && TREE_CODE (op0) == NOP_EXPR
1973 && TYPE_PRECISION (type0) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))
1974 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
1976 final_type = result_type;
1977 op0 = TREE_OPERAND (op0, 0);
1978 result_type = TREE_TYPE (op0);
1982 case TRUNC_MOD_EXPR:
1983 case FLOOR_MOD_EXPR:
1984 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
1988 case TRUTH_ANDIF_EXPR:
1989 case TRUTH_ORIF_EXPR:
1990 case TRUTH_AND_EXPR:
1992 case TRUTH_XOR_EXPR:
1993 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
1994 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
1995 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
1996 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
1998 /* Result of these operations is always an int,
1999 but that does not mean the operands should be
2000 converted to ints! */
2001 result_type = integer_type_node;
2002 op0 = truthvalue_conversion (op0);
2003 op1 = truthvalue_conversion (op1);
2008 /* Shift operations: result has same type as first operand;
2009 always convert second operand to int.
2010 Also set SHORT_SHIFT if shifting rightward. */
2013 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2015 if (TREE_CODE (op1) == INTEGER_CST)
2017 if (tree_int_cst_lt (op1, integer_zero_node))
2018 warning ("right shift count is negative");
2021 if (TREE_INT_CST_LOW (op1) | TREE_INT_CST_HIGH (op1))
2023 if (TREE_INT_CST_HIGH (op1) != 0
2024 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2025 >= TYPE_PRECISION (type0)))
2026 warning ("right shift count >= width of type");
2029 /* Use the type of the value to be shifted.
2030 This is what most traditional C compilers do. */
2031 result_type = type0;
2032 /* Unless traditional, convert the shift-count to an integer,
2033 regardless of size of value being shifted. */
2034 if (! flag_traditional)
2036 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2037 op1 = convert (integer_type_node, op1);
2038 /* Avoid converting op1 to result_type later. */
2045 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2047 if (TREE_CODE (op1) == INTEGER_CST)
2049 if (tree_int_cst_lt (op1, integer_zero_node))
2050 warning ("left shift count is negative");
2051 else if (TREE_INT_CST_HIGH (op1) != 0
2052 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2053 >= TYPE_PRECISION (type0)))
2054 warning ("left shift count >= width of type");
2056 /* Use the type of the value to be shifted.
2057 This is what most traditional C compilers do. */
2058 result_type = type0;
2059 /* Unless traditional, convert the shift-count to an integer,
2060 regardless of size of value being shifted. */
2061 if (! flag_traditional)
2063 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2064 op1 = convert (integer_type_node, op1);
2065 /* Avoid converting op1 to result_type later. */
2073 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2075 if (TREE_CODE (op1) == INTEGER_CST)
2077 if (tree_int_cst_lt (op1, integer_zero_node))
2078 warning ("shift count is negative");
2079 else if (TREE_INT_CST_HIGH (op1) != 0
2080 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2081 >= TYPE_PRECISION (type0)))
2082 warning ("shift count >= width of type");
2084 /* Use the type of the value to be shifted.
2085 This is what most traditional C compilers do. */
2086 result_type = type0;
2087 /* Unless traditional, convert the shift-count to an integer,
2088 regardless of size of value being shifted. */
2089 if (! flag_traditional)
2091 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2092 op1 = convert (integer_type_node, op1);
2093 /* Avoid converting op1 to result_type later. */
2101 /* Result of comparison is always int,
2102 but don't convert the args to int! */
2103 result_type = integer_type_node;
2105 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2106 || code0 == COMPLEX_TYPE)
2107 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2108 || code1 == COMPLEX_TYPE))
2110 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2112 register tree tt0 = TREE_TYPE (type0);
2113 register tree tt1 = TREE_TYPE (type1);
2114 /* Anything compares with void *. void * compares with anything.
2115 Otherwise, the targets must be compatible
2116 and both must be object or both incomplete. */
2117 if (comp_target_types (type0, type1))
2119 else if (TYPE_MAIN_VARIANT (tt0) == void_type_node)
2121 /* op0 != orig_op0 detects the case of something
2122 whose value is 0 but which isn't a valid null ptr const. */
2123 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
2124 && TREE_CODE (tt1) == FUNCTION_TYPE)
2125 pedwarn ("ANSI C forbids comparison of `void *' with function pointer");
2127 else if (TYPE_MAIN_VARIANT (tt1) == void_type_node)
2129 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
2130 && TREE_CODE (tt0) == FUNCTION_TYPE)
2131 pedwarn ("ANSI C forbids comparison of `void *' with function pointer");
2134 pedwarn ("comparison of distinct pointer types lacks a cast");
2136 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2137 && integer_zerop (op1))
2138 op1 = null_pointer_node;
2139 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2140 && integer_zerop (op0))
2141 op0 = null_pointer_node;
2142 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2144 if (! flag_traditional)
2145 pedwarn ("comparison between pointer and integer");
2146 op1 = convert (TREE_TYPE (op0), op1);
2148 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2150 if (! flag_traditional)
2151 pedwarn ("comparison between pointer and integer");
2152 op0 = convert (TREE_TYPE (op1), op0);
2155 /* If args are not valid, clear out RESULT_TYPE
2156 to cause an error message later. */
2162 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2163 || code0 == COMPLEX_TYPE)
2164 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2165 || code1 == COMPLEX_TYPE))
2167 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2169 if (! comp_target_types (type0, type1))
2170 pedwarn ("comparison of distinct pointer types lacks a cast");
2172 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2173 pedwarn ("ANSI C forbids ordered comparisons of pointers to functions");
2174 result_type = common_type (type0, type1);
2182 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2183 || code0 == COMPLEX_TYPE)
2184 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2185 || code1 == COMPLEX_TYPE))
2187 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2189 if (! comp_target_types (type0, type1))
2190 pedwarn ("comparison of distinct pointer types lacks a cast");
2191 else if ((TYPE_SIZE (TREE_TYPE (type0)) != 0)
2192 != (TYPE_SIZE (TREE_TYPE (type1)) != 0))
2193 pedwarn ("comparison of complete and incomplete pointers");
2195 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2196 pedwarn ("ANSI C forbids ordered comparisons of pointers to functions");
2197 result_type = integer_type_node;
2199 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2200 && integer_zerop (op1))
2202 result_type = integer_type_node;
2203 op1 = null_pointer_node;
2204 if (! flag_traditional)
2205 pedwarn ("ordered comparison of pointer with integer zero");
2207 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2208 && integer_zerop (op0))
2210 result_type = integer_type_node;
2211 op0 = null_pointer_node;
2213 pedwarn ("ordered comparison of pointer with integer zero");
2215 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2217 result_type = integer_type_node;
2218 if (! flag_traditional)
2219 pedwarn ("comparison between pointer and integer");
2220 op1 = convert (TREE_TYPE (op0), op1);
2222 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2224 result_type = integer_type_node;
2225 if (! flag_traditional)
2226 pedwarn ("comparison between pointer and integer");
2227 op0 = convert (TREE_TYPE (op1), op0);
2233 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2235 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2237 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
2239 if (shorten || common || short_compare)
2240 result_type = common_type (type0, type1);
2242 /* For certain operations (which identify themselves by shorten != 0)
2243 if both args were extended from the same smaller type,
2244 do the arithmetic in that type and then extend.
2246 shorten !=0 and !=1 indicates a bitwise operation.
2247 For them, this optimization is safe only if
2248 both args are zero-extended or both are sign-extended.
2249 Otherwise, we might change the result.
2250 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2251 but calculated in (unsigned short) it would be (unsigned short)-1. */
2253 if (shorten && none_complex)
2255 int unsigned0, unsigned1;
2256 tree arg0 = get_narrower (op0, &unsigned0);
2257 tree arg1 = get_narrower (op1, &unsigned1);
2258 /* UNS is 1 if the operation to be done is an unsigned one. */
2259 int uns = TREE_UNSIGNED (result_type);
2262 final_type = result_type;
2264 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2265 but it *requires* conversion to FINAL_TYPE. */
2267 if ((TYPE_PRECISION (TREE_TYPE (op0))
2268 == TYPE_PRECISION (TREE_TYPE (arg0)))
2269 && TREE_TYPE (op0) != final_type)
2270 unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
2271 if ((TYPE_PRECISION (TREE_TYPE (op1))
2272 == TYPE_PRECISION (TREE_TYPE (arg1)))
2273 && TREE_TYPE (op1) != final_type)
2274 unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
2276 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2278 /* For bitwise operations, signedness of nominal type
2279 does not matter. Consider only how operands were extended. */
2283 /* Note that in all three cases below we refrain from optimizing
2284 an unsigned operation on sign-extended args.
2285 That would not be valid. */
2287 /* Both args variable: if both extended in same way
2288 from same width, do it in that width.
2289 Do it unsigned if args were zero-extended. */
2290 if ((TYPE_PRECISION (TREE_TYPE (arg0))
2291 < TYPE_PRECISION (result_type))
2292 && (TYPE_PRECISION (TREE_TYPE (arg1))
2293 == TYPE_PRECISION (TREE_TYPE (arg0)))
2294 && unsigned0 == unsigned1
2295 && (unsigned0 || !uns))
2297 = signed_or_unsigned_type (unsigned0,
2298 common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
2299 else if (TREE_CODE (arg0) == INTEGER_CST
2300 && (unsigned1 || !uns)
2301 && (TYPE_PRECISION (TREE_TYPE (arg1))
2302 < TYPE_PRECISION (result_type))
2303 && (type = signed_or_unsigned_type (unsigned1,
2305 int_fits_type_p (arg0, type)))
2307 else if (TREE_CODE (arg1) == INTEGER_CST
2308 && (unsigned0 || !uns)
2309 && (TYPE_PRECISION (TREE_TYPE (arg0))
2310 < TYPE_PRECISION (result_type))
2311 && (type = signed_or_unsigned_type (unsigned0,
2313 int_fits_type_p (arg1, type)))
2317 /* Shifts can be shortened if shifting right. */
2322 tree arg0 = get_narrower (op0, &unsigned_arg);
2324 final_type = result_type;
2326 if (arg0 == op0 && final_type == TREE_TYPE (op0))
2327 unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
2329 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
2330 /* If arg is sign-extended and then unsigned-shifted,
2331 we can simulate this with a signed shift in arg's type
2332 only if the extended result is at least twice as wide
2333 as the arg. Otherwise, the shift could use up all the
2334 ones made by sign-extension and bring in zeros.
2335 We can't optimize that case at all, but in most machines
2336 it never happens because available widths are 2**N. */
2337 && (!TREE_UNSIGNED (final_type)
2339 || 2 * TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (result_type)))
2341 /* Do an unsigned shift if the operand was zero-extended. */
2343 = signed_or_unsigned_type (unsigned_arg,
2345 /* Convert value-to-be-shifted to that type. */
2346 if (TREE_TYPE (op0) != result_type)
2347 op0 = convert (result_type, op0);
2352 /* Comparison operations are shortened too but differently.
2353 They identify themselves by setting short_compare = 1. */
2355 if (short_compare && none_complex)
2357 /* Don't write &op0, etc., because that would prevent op0
2358 from being kept in a register.
2359 Instead, make copies of the our local variables and
2360 pass the copies by reference, then copy them back afterward. */
2361 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
2362 enum tree_code xresultcode = resultcode;
2364 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
2367 op0 = xop0, op1 = xop1, result_type = xresult_type;
2368 resultcode = xresultcode;
2372 tree op0_type = TREE_TYPE (orig_op0);
2373 tree op1_type = TREE_TYPE (orig_op1);
2374 int op0_unsigned = TREE_UNSIGNED (op0_type);
2375 int op1_unsigned = TREE_UNSIGNED (op1_type);
2377 /* Give warnings for comparisons between signed and unsigned
2378 quantities that will fail. Do not warn if the signed quantity
2379 is an unsuffixed integer literal (or some static constant
2380 expression involving such literals) and it is positive.
2381 Do not warn if the width of the unsigned quantity is less
2382 than that of the signed quantity, since in this case all
2383 values of the unsigned quantity fit in the signed quantity.
2384 Do not warn if the signed type is the same size as the
2385 result_type since sign extension does not cause trouble in
2387 /* Do the checking based on the original operand trees, so that
2388 casts will be considered, but default promotions won't be. */
2389 if (op0_unsigned != op1_unsigned
2391 && TYPE_PRECISION (op0_type) >= TYPE_PRECISION (op1_type)
2392 && TYPE_PRECISION (op0_type) < TYPE_PRECISION (result_type)
2393 && (TREE_CODE (op1) != INTEGER_CST
2394 || (TREE_CODE (op1) == INTEGER_CST
2395 && INT_CST_LT (op1, integer_zero_node))))
2398 && TYPE_PRECISION (op1_type) >= TYPE_PRECISION (op0_type)
2399 && TYPE_PRECISION (op1_type) < TYPE_PRECISION (result_type)
2400 && (TREE_CODE (op0) != INTEGER_CST
2401 || (TREE_CODE (op0) == INTEGER_CST
2402 && INT_CST_LT (op0, integer_zero_node))))))
2403 warning ("comparison between signed and unsigned");
2408 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2409 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2410 Then the expression will be built.
2411 It will be given type FINAL_TYPE if that is nonzero;
2412 otherwise, it will be given type RESULT_TYPE. */
2416 binary_op_error (code);
2417 return error_mark_node;
2422 if (TREE_TYPE (op0) != result_type)
2423 op0 = convert (result_type, op0);
2424 if (TREE_TYPE (op1) != result_type)
2425 op1 = convert (result_type, op1);
2429 register tree result = build (resultcode, result_type, op0, op1);
2430 register tree folded;
2432 folded = fold (result);
2433 if (folded == result)
2434 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2435 if (final_type != 0)
2436 return convert (final_type, folded);
2441 /* Return a tree for the sum or difference (RESULTCODE says which)
2442 of pointer PTROP and integer INTOP. */
2445 pointer_int_sum (resultcode, ptrop, intop)
2446 enum tree_code resultcode;
2447 register tree ptrop, intop;
2451 register tree result;
2452 register tree folded;
2454 /* The result is a pointer of the same type that is being added. */
2456 register tree result_type = TREE_TYPE (ptrop);
2458 if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
2460 if (pedantic || warn_pointer_arith)
2461 pedwarn ("pointer of type `void *' used in arithmetic");
2462 size_exp = integer_one_node;
2464 else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
2466 if (pedantic || warn_pointer_arith)
2467 pedwarn ("pointer to a function used in arithmetic");
2468 size_exp = integer_one_node;
2471 size_exp = c_size_in_bytes (TREE_TYPE (result_type));
2473 /* If what we are about to multiply by the size of the elements
2474 contains a constant term, apply distributive law
2475 and multiply that constant term separately.
2476 This helps produce common subexpressions. */
2478 if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
2479 && ! TREE_CONSTANT (intop)
2480 && TREE_CONSTANT (TREE_OPERAND (intop, 1))
2481 && TREE_CONSTANT (size_exp)
2482 /* If the constant comes from pointer subtraction,
2483 skip this optimization--it would cause an error. */
2484 && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE)
2486 enum tree_code subcode = resultcode;
2487 tree int_type = TREE_TYPE (intop);
2488 if (TREE_CODE (intop) == MINUS_EXPR)
2489 subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
2490 /* Convert both subexpression types to the type of intop,
2491 because weird cases involving pointer arithmetic
2492 can result in a sum or difference with different type args. */
2493 ptrop = build_binary_op (subcode, ptrop,
2494 convert (int_type, TREE_OPERAND (intop, 1)), 1);
2495 intop = convert (int_type, TREE_OPERAND (intop, 0));
2498 /* Convert the integer argument to a type the same size as a pointer
2499 so the multiply won't overflow spuriously. */
2501 if (TYPE_PRECISION (TREE_TYPE (intop)) != POINTER_SIZE)
2502 intop = convert (type_for_size (POINTER_SIZE, 0), intop);
2504 /* Replace the integer argument
2505 with a suitable product by the object size. */
2507 intop = build_binary_op (MULT_EXPR, intop, size_exp, 1);
2509 /* Create the sum or difference. */
2511 result = build (resultcode, result_type, ptrop, intop);
2513 folded = fold (result);
2514 if (folded == result)
2515 TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop);
2519 /* Return a tree for the difference of pointers OP0 and OP1.
2520 The resulting tree has type int. */
2523 pointer_diff (op0, op1)
2524 register tree op0, op1;
2526 register tree result, folded;
2527 tree restype = ptrdiff_type_node;
2529 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2531 if (pedantic || warn_pointer_arith)
2533 if (TREE_CODE (target_type) == VOID_TYPE)
2534 pedwarn ("pointer of type `void *' used in subtraction");
2535 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2536 pedwarn ("pointer to a function used in subtraction");
2539 /* First do the subtraction as integers;
2540 then drop through to build the divide operator. */
2542 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2543 convert (restype, op1), 1);
2544 /* This generates an error if op1 is pointer to incomplete type. */
2545 if (TYPE_SIZE (TREE_TYPE (TREE_TYPE (op1))) == 0)
2546 error ("arithmetic on pointer to an incomplete type");
2547 /* This generates an error if op0 is pointer to incomplete type. */
2548 op1 = c_size_in_bytes (target_type);
2550 /* Divide by the size, in easiest possible way. */
2552 result = build (EXACT_DIV_EXPR, restype, op0, op1);
2554 folded = fold (result);
2555 if (folded == result)
2556 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2560 /* Construct and perhaps optimize a tree representation
2561 for a unary operation. CODE, a tree_code, specifies the operation
2562 and XARG is the operand. NOCONVERT nonzero suppresses
2563 the default promotions (such as from short to int). */
2566 build_unary_op (code, xarg, noconvert)
2567 enum tree_code code;
2571 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2572 register tree arg = xarg;
2573 register tree argtype = 0;
2574 register enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2575 char *errstring = NULL;
2578 if (typecode == ERROR_MARK)
2579 return error_mark_node;
2580 if (typecode == ENUMERAL_TYPE)
2581 typecode = INTEGER_TYPE;
2586 /* This is used for unary plus, because a CONVERT_EXPR
2587 is enough to prevent anybody from looking inside for
2588 associativity, but won't generate any code. */
2589 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2590 || typecode == COMPLEX_TYPE))
2591 errstring = "wrong type argument to unary plus";
2592 else if (!noconvert)
2593 arg = default_conversion (arg);
2597 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2598 || typecode == COMPLEX_TYPE))
2599 errstring = "wrong type argument to unary minus";
2600 else if (!noconvert)
2601 arg = default_conversion (arg);
2605 if (typecode == COMPLEX_TYPE)
2609 arg = default_conversion (arg);
2611 else if (typecode != INTEGER_TYPE)
2612 errstring = "wrong type argument to bit-complement";
2613 else if (!noconvert)
2614 arg = default_conversion (arg);
2618 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2619 || typecode == COMPLEX_TYPE))
2620 errstring = "wrong type argument to abs";
2621 else if (!noconvert)
2622 arg = default_conversion (arg);
2626 /* Conjugating a real value is a no-op, but allow it anyway. */
2627 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2628 || typecode == COMPLEX_TYPE))
2629 errstring = "wrong type argument to conjugation";
2630 else if (!noconvert)
2631 arg = default_conversion (arg);
2634 case TRUTH_NOT_EXPR:
2635 if (typecode != INTEGER_TYPE
2636 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2637 && typecode != COMPLEX_TYPE
2638 /* These will convert to a pointer. */
2639 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2641 errstring = "wrong type argument to unary exclamation mark";
2644 arg = truthvalue_conversion (arg);
2645 return invert_truthvalue (arg);
2651 if (TREE_CODE (arg) == COMPLEX_CST)
2652 return TREE_REALPART (arg);
2653 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2654 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2659 if (TREE_CODE (arg) == COMPLEX_CST)
2660 return TREE_IMAGPART (arg);
2661 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2662 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2664 return convert (TREE_TYPE (arg), integer_zero_node);
2666 case PREINCREMENT_EXPR:
2667 case POSTINCREMENT_EXPR:
2668 case PREDECREMENT_EXPR:
2669 case POSTDECREMENT_EXPR:
2670 /* Handle complex lvalues (when permitted)
2671 by reduction to simpler cases. */
2673 val = unary_complex_lvalue (code, arg);
2677 /* Increment or decrement the real part of the value,
2678 and don't change the imaginary part. */
2679 if (typecode == COMPLEX_TYPE)
2683 arg = stabilize_reference (arg);
2684 real = build_unary_op (REALPART_EXPR, arg, 1);
2685 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2686 return build (COMPLEX_EXPR, TREE_TYPE (arg),
2687 build_unary_op (code, real, 1), imag);
2690 /* Report invalid types. */
2692 if (typecode != POINTER_TYPE
2693 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2695 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2696 errstring ="wrong type argument to increment";
2698 errstring ="wrong type argument to decrement";
2704 tree result_type = TREE_TYPE (arg);
2706 arg = get_unwidened (arg, 0);
2707 argtype = TREE_TYPE (arg);
2709 /* Compute the increment. */
2711 if (typecode == POINTER_TYPE)
2713 /* If pointer target is an undefined struct,
2714 we just cannot know how to do the arithmetic. */
2715 if (TYPE_SIZE (TREE_TYPE (result_type)) == 0)
2716 error ("%s of pointer to unknown structure",
2717 ((code == PREINCREMENT_EXPR
2718 || code == POSTINCREMENT_EXPR)
2719 ? "increment" : "decrement"));
2720 else if ((pedantic || warn_pointer_arith)
2721 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2722 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2723 pedwarn ("wrong type argument to %s",
2724 ((code == PREINCREMENT_EXPR
2725 || code == POSTINCREMENT_EXPR)
2726 ? "increment" : "decrement"));
2727 inc = c_sizeof_nowarn (TREE_TYPE (result_type));
2730 inc = integer_one_node;
2732 inc = convert (argtype, inc);
2734 /* Handle incrementing a cast-expression. */
2737 switch (TREE_CODE (arg))
2742 case FIX_TRUNC_EXPR:
2743 case FIX_FLOOR_EXPR:
2744 case FIX_ROUND_EXPR:
2746 pedantic_lvalue_warning (CONVERT_EXPR);
2747 /* If the real type has the same machine representation
2748 as the type it is cast to, we can make better output
2749 by adding directly to the inside of the cast. */
2750 if ((TREE_CODE (TREE_TYPE (arg))
2751 == TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0))))
2752 && (TYPE_MODE (TREE_TYPE (arg))
2753 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (arg, 0)))))
2754 arg = TREE_OPERAND (arg, 0);
2757 tree incremented, modify, value;
2758 arg = stabilize_reference (arg);
2759 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
2762 value = save_expr (arg);
2763 incremented = build (((code == PREINCREMENT_EXPR
2764 || code == POSTINCREMENT_EXPR)
2765 ? PLUS_EXPR : MINUS_EXPR),
2766 argtype, value, inc);
2767 TREE_SIDE_EFFECTS (incremented) = 1;
2768 modify = build_modify_expr (arg, NOP_EXPR, incremented);
2769 value = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
2770 TREE_USED (value) = 1;
2780 /* Complain about anything else that is not a true lvalue. */
2781 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2782 || code == POSTINCREMENT_EXPR)
2783 ? "increment" : "decrement")))
2784 return error_mark_node;
2786 /* Report a read-only lvalue. */
2787 if (TREE_READONLY (arg))
2788 readonly_warning (arg,
2789 ((code == PREINCREMENT_EXPR
2790 || code == POSTINCREMENT_EXPR)
2791 ? "increment" : "decrement"));
2793 val = build (code, TREE_TYPE (arg), arg, inc);
2794 TREE_SIDE_EFFECTS (val) = 1;
2795 val = convert (result_type, val);
2796 if (TREE_CODE (val) != code)
2797 TREE_NO_UNUSED_WARNING (val) = 1;
2802 /* Note that this operation never does default_conversion
2803 regardless of NOCONVERT. */
2805 /* Let &* cancel out to simplify resulting code. */
2806 if (TREE_CODE (arg) == INDIRECT_REF)
2808 /* Don't let this be an lvalue. */
2809 if (lvalue_p (TREE_OPERAND (arg, 0)))
2810 return non_lvalue (TREE_OPERAND (arg, 0));
2811 return TREE_OPERAND (arg, 0);
2814 /* For &x[y], return x+y */
2815 if (TREE_CODE (arg) == ARRAY_REF)
2817 if (mark_addressable (TREE_OPERAND (arg, 0)) == 0)
2818 return error_mark_node;
2819 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
2820 TREE_OPERAND (arg, 1), 1);
2823 /* Handle complex lvalues (when permitted)
2824 by reduction to simpler cases. */
2825 val = unary_complex_lvalue (code, arg);
2829 #if 0 /* Turned off because inconsistent;
2830 float f; *&(int)f = 3.4 stores in int format
2831 whereas (int)f = 3.4 stores in float format. */
2832 /* Address of a cast is just a cast of the address
2833 of the operand of the cast. */
2834 switch (TREE_CODE (arg))
2839 case FIX_TRUNC_EXPR:
2840 case FIX_FLOOR_EXPR:
2841 case FIX_ROUND_EXPR:
2844 pedwarn ("ANSI C forbids the address of a cast expression");
2845 return convert (build_pointer_type (TREE_TYPE (arg)),
2846 build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0),
2851 /* Allow the address of a constructor if all the elements
2853 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_CONSTANT (arg))
2855 /* Anything not already handled and not a true memory reference
2857 else if (typecode != FUNCTION_TYPE && !lvalue_or_else (arg, "unary `&'"))
2858 return error_mark_node;
2860 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
2861 argtype = TREE_TYPE (arg);
2862 /* If the lvalue is const or volatile,
2863 merge that into the type that the address will point to. */
2864 if (TREE_CODE_CLASS (TREE_CODE (arg)) == 'd'
2865 || TREE_CODE_CLASS (TREE_CODE (arg)) == 'r')
2867 if (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg))
2868 argtype = c_build_type_variant (argtype,
2869 TREE_READONLY (arg),
2870 TREE_THIS_VOLATILE (arg));
2873 argtype = build_pointer_type (argtype);
2875 if (mark_addressable (arg) == 0)
2876 return error_mark_node;
2881 if (TREE_CODE (arg) == COMPONENT_REF)
2883 tree field = TREE_OPERAND (arg, 1);
2885 addr = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
2887 if (DECL_BIT_FIELD (field))
2889 error ("attempt to take address of bit-field structure member `%s'",
2890 IDENTIFIER_POINTER (DECL_NAME (field)));
2891 return error_mark_node;
2894 addr = convert (argtype, addr);
2896 if (! integer_zerop (DECL_FIELD_BITPOS (field)))
2899 = size_binop (EASY_DIV_EXPR, DECL_FIELD_BITPOS (field),
2900 size_int (BITS_PER_UNIT));
2901 int flag = TREE_CONSTANT (addr);
2902 addr = fold (build (PLUS_EXPR, argtype,
2903 addr, convert (argtype, offset)));
2904 TREE_CONSTANT (addr) = flag;
2908 addr = build1 (code, argtype, arg);
2910 /* Address of a static or external variable or
2911 file-scope function counts as a constant. */
2913 && ! (TREE_CODE (arg) == FUNCTION_DECL
2914 && DECL_CONTEXT (arg) != 0))
2915 TREE_CONSTANT (addr) = 1;
2923 argtype = TREE_TYPE (arg);
2924 return fold (build1 (code, argtype, arg));
2928 return error_mark_node;
2932 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
2933 convert ARG with the same conversions in the same order
2934 and return the result. */
2937 convert_sequence (conversions, arg)
2941 switch (TREE_CODE (conversions))
2946 case FIX_TRUNC_EXPR:
2947 case FIX_FLOOR_EXPR:
2948 case FIX_ROUND_EXPR:
2950 return convert (TREE_TYPE (conversions),
2951 convert_sequence (TREE_OPERAND (conversions, 0),
2960 /* Return nonzero if REF is an lvalue valid for this language.
2961 Lvalues can be assigned, unless their type has TYPE_READONLY.
2962 Lvalues can have their address taken, unless they have DECL_REGISTER. */
2968 register enum tree_code code = TREE_CODE (ref);
2975 return lvalue_p (TREE_OPERAND (ref, 0));
2986 if (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
2987 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE)
2994 /* Return nonzero if REF is an lvalue valid for this language;
2995 otherwise, print an error message and return zero. */
2998 lvalue_or_else (ref, string)
3002 int win = lvalue_p (ref);
3004 error ("invalid lvalue in %s", string);
3008 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3009 for certain kinds of expressions which are not really lvalues
3010 but which we can accept as lvalues.
3012 If ARG is not a kind of expression we can handle, return zero. */
3015 unary_complex_lvalue (code, arg)
3016 enum tree_code code;
3019 /* Handle (a, b) used as an "lvalue". */
3020 if (TREE_CODE (arg) == COMPOUND_EXPR)
3022 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
3023 pedantic_lvalue_warning (COMPOUND_EXPR);
3024 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
3025 TREE_OPERAND (arg, 0), real_result);
3028 /* Handle (a ? b : c) used as an "lvalue". */
3029 if (TREE_CODE (arg) == COND_EXPR)
3031 pedantic_lvalue_warning (COND_EXPR);
3032 return (build_conditional_expr
3033 (TREE_OPERAND (arg, 0),
3034 build_unary_op (code, TREE_OPERAND (arg, 1), 0),
3035 build_unary_op (code, TREE_OPERAND (arg, 2), 0)));
3041 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3042 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3045 pedantic_lvalue_warning (code)
3046 enum tree_code code;
3049 pedwarn ("ANSI C forbids use of %s expressions as lvalues",
3050 code == COND_EXPR ? "conditional"
3051 : code == COMPOUND_EXPR ? "compound" : "cast");
3054 /* Warn about storing in something that is `const'. */
3057 readonly_warning (arg, string)
3062 strcpy (buf, string);
3064 /* Forbid assignments to iterators. */
3065 if (TREE_CODE (arg) == VAR_DECL && ITERATOR_P (arg))
3067 strcat (buf, " of iterator `%s'");
3068 pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (arg)));
3071 if (TREE_CODE (arg) == COMPONENT_REF)
3073 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3074 readonly_warning (TREE_OPERAND (arg, 0), string);
3077 strcat (buf, " of read-only member `%s'");
3078 pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1))));
3081 else if (TREE_CODE (arg) == VAR_DECL)
3083 strcat (buf, " of read-only variable `%s'");
3084 pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (arg)));
3088 pedwarn ("%s of read-only location", buf);
3092 /* Mark EXP saying that we need to be able to take the
3093 address of it; it should not be allocated in a register.
3094 Value is 1 if successful. */
3097 mark_addressable (exp)
3100 register tree x = exp;
3102 switch (TREE_CODE (x))
3107 x = TREE_OPERAND (x, 0);
3111 TREE_ADDRESSABLE (x) = 1;
3118 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
3119 && DECL_NONLOCAL (x))
3121 if (TREE_PUBLIC (x))
3123 error ("global register variable `%s' used in nested function",
3124 IDENTIFIER_POINTER (DECL_NAME (x)));
3127 pedwarn ("register variable `%s' used in nested function",
3128 IDENTIFIER_POINTER (DECL_NAME (x)));
3130 else if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x))
3132 if (TREE_PUBLIC (x))
3134 error ("address of global register variable `%s' requested",
3135 IDENTIFIER_POINTER (DECL_NAME (x)));
3138 pedwarn ("address of register variable `%s' requested",
3139 IDENTIFIER_POINTER (DECL_NAME (x)));
3141 put_var_into_stack (x);
3145 TREE_ADDRESSABLE (x) = 1;
3146 #if 0 /* poplevel deals with this now. */
3147 if (DECL_CONTEXT (x) == 0)
3148 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
3156 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3159 build_conditional_expr (ifexp, op1, op2)
3160 tree ifexp, op1, op2;
3162 register tree type1;
3163 register tree type2;
3164 register enum tree_code code1;
3165 register enum tree_code code2;
3166 register tree result_type = NULL;
3167 tree orig_op1 = op1, orig_op2 = op2;
3169 /* If second operand is omitted, it is the same as the first one;
3170 make sure it is calculated only once. */
3174 pedwarn ("ANSI C forbids omitting the middle term of a ?: expression");
3175 ifexp = op1 = save_expr (ifexp);
3178 ifexp = truthvalue_conversion (default_conversion (ifexp));
3180 #if 0 /* Produces wrong result if within sizeof. */
3181 /* Don't promote the operands separately if they promote
3182 the same way. Return the unpromoted type and let the combined
3183 value get promoted if necessary. */
3185 if (TREE_TYPE (op1) == TREE_TYPE (op2)
3186 && TREE_CODE (TREE_TYPE (op1)) != ARRAY_TYPE
3187 && TREE_CODE (TREE_TYPE (op1)) != ENUMERAL_TYPE
3188 && TREE_CODE (TREE_TYPE (op1)) != FUNCTION_TYPE)
3190 if (TREE_CODE (ifexp) == INTEGER_CST)
3191 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3193 return fold (build (COND_EXPR, TREE_TYPE (op1), ifexp, op1, op2));
3197 /* Promote both alternatives. */
3199 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3200 op1 = default_conversion (op1);
3201 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3202 op2 = default_conversion (op2);
3204 if (TREE_CODE (ifexp) == ERROR_MARK
3205 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3206 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3207 return error_mark_node;
3209 type1 = TREE_TYPE (op1);
3210 code1 = TREE_CODE (type1);
3211 type2 = TREE_TYPE (op2);
3212 code2 = TREE_CODE (type2);
3214 /* Quickly detect the usual case where op1 and op2 have the same type
3216 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3219 result_type = type1;
3221 result_type = TYPE_MAIN_VARIANT (type1);
3223 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE)
3224 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE))
3226 result_type = common_type (type1, type2);
3228 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3230 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3231 pedwarn ("ANSI C forbids conditional expr with only one void side");
3232 result_type = void_type_node;
3234 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3236 if (comp_target_types (type1, type2))
3237 result_type = common_type (type1, type2);
3238 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
3239 && TREE_CODE (orig_op1) != NOP_EXPR)
3240 result_type = qualify_type (type2, type1);
3241 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
3242 && TREE_CODE (orig_op2) != NOP_EXPR)
3243 result_type = qualify_type (type1, type2);
3244 else if (TYPE_MAIN_VARIANT (TREE_TYPE (type1)) == void_type_node)
3246 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3247 pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer");
3248 result_type = qualify_type (type1, type2);
3250 else if (TYPE_MAIN_VARIANT (TREE_TYPE (type2)) == void_type_node)
3252 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3253 pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer");
3254 result_type = qualify_type (type2, type1);
3258 pedwarn ("pointer type mismatch in conditional expression");
3259 result_type = build_pointer_type (void_type_node);
3262 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3264 if (! integer_zerop (op2))
3265 pedwarn ("pointer/integer type mismatch in conditional expression");
3268 op2 = null_pointer_node;
3269 #if 0 /* The spec seems to say this is permitted. */
3270 if (pedantic && TREE_CODE (type1) == FUNCTION_TYPE)
3271 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3274 result_type = type1;
3276 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3278 if (!integer_zerop (op1))
3279 pedwarn ("pointer/integer type mismatch in conditional expression");
3282 op1 = null_pointer_node;
3283 #if 0 /* The spec seems to say this is permitted. */
3284 if (pedantic && TREE_CODE (type2) == FUNCTION_TYPE)
3285 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3288 result_type = type2;
3293 if (flag_cond_mismatch)
3294 result_type = void_type_node;
3297 error ("type mismatch in conditional expression");
3298 return error_mark_node;
3302 /* Merge const and volatile flags of the incoming types. */
3304 = build_type_variant (result_type,
3305 TREE_READONLY (op1) || TREE_READONLY (op2),
3306 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3308 if (result_type != TREE_TYPE (op1))
3309 op1 = convert_and_check (result_type, op1);
3310 if (result_type != TREE_TYPE (op2))
3311 op2 = convert_and_check (result_type, op2);
3314 if (code1 == RECORD_TYPE || code1 == UNION_TYPE)
3316 result_type = TREE_TYPE (op1);
3317 if (TREE_CONSTANT (ifexp))
3318 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3320 if (TYPE_MODE (result_type) == BLKmode)
3322 register tree tempvar
3323 = build_decl (VAR_DECL, NULL_TREE, result_type);
3324 register tree xop1 = build_modify_expr (tempvar, op1);
3325 register tree xop2 = build_modify_expr (tempvar, op2);
3326 register tree result = fold (build (COND_EXPR, result_type,
3327 ifexp, xop1, xop2));
3329 layout_decl (tempvar, TYPE_ALIGN (result_type));
3330 /* No way to handle variable-sized objects here.
3331 I fear that the entire handling of BLKmode conditional exprs
3332 needs to be redone. */
3333 if (TREE_CODE (DECL_SIZE (tempvar)) != INTEGER_CST)
3336 = assign_stack_local (DECL_MODE (tempvar),
3337 (TREE_INT_CST_LOW (DECL_SIZE (tempvar))
3338 + BITS_PER_UNIT - 1)
3342 TREE_SIDE_EFFECTS (result)
3343 = TREE_SIDE_EFFECTS (ifexp) | TREE_SIDE_EFFECTS (op1)
3344 | TREE_SIDE_EFFECTS (op2);
3345 return build (COMPOUND_EXPR, result_type, result, tempvar);
3350 if (TREE_CODE (ifexp) == INTEGER_CST)
3351 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3353 return fold (build (COND_EXPR, result_type, ifexp, op1, op2));
3356 /* Given a list of expressions, return a compound expression
3357 that performs them all and returns the value of the last of them. */
3360 build_compound_expr (list)
3363 return internal_build_compound_expr (list, TRUE);
3367 internal_build_compound_expr (list, first_p)
3373 if (TREE_CHAIN (list) == 0)
3375 #if 0 /* If something inside inhibited lvalueness, we should not override. */
3376 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3378 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3379 if (TREE_CODE (list) == NON_LVALUE_EXPR)
3380 list = TREE_OPERAND (list, 0);
3383 /* Don't let (0, 0) be null pointer constant. */
3384 if (!first_p && integer_zerop (TREE_VALUE (list)))
3385 return non_lvalue (TREE_VALUE (list));
3386 return TREE_VALUE (list);
3389 if (TREE_CHAIN (list) != 0 && TREE_CHAIN (TREE_CHAIN (list)) == 0)
3391 /* Convert arrays to pointers when there really is a comma operator. */
3392 if (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (list)))) == ARRAY_TYPE)
3393 TREE_VALUE (TREE_CHAIN (list))
3394 = default_conversion (TREE_VALUE (TREE_CHAIN (list)));
3397 rest = internal_build_compound_expr (TREE_CHAIN (list), FALSE);
3399 /* When pedantic, a compound expression can be neither an lvalue
3400 nor an integer constant expression. */
3401 if (! TREE_SIDE_EFFECTS (TREE_VALUE (list)) && ! pedantic)
3404 return build (COMPOUND_EXPR, TREE_TYPE (rest), TREE_VALUE (list), rest);
3407 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3410 build_c_cast (type, expr)
3414 register tree value = expr;
3416 if (type == error_mark_node || expr == error_mark_node)
3417 return error_mark_node;
3418 type = TYPE_MAIN_VARIANT (type);
3421 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3422 if (TREE_CODE (value) == NON_LVALUE_EXPR)
3423 value = TREE_OPERAND (value, 0);
3426 if (TREE_CODE (type) == ARRAY_TYPE)
3428 error ("cast specifies array type");
3429 return error_mark_node;
3432 if (TREE_CODE (type) == FUNCTION_TYPE)
3434 error ("cast specifies function type");
3435 return error_mark_node;
3438 if (type == TREE_TYPE (value))
3442 if (TREE_CODE (type) == RECORD_TYPE
3443 || TREE_CODE (type) == UNION_TYPE)
3444 pedwarn ("ANSI C forbids casting nonscalar to the same type");
3447 else if (TREE_CODE (type) == UNION_TYPE)
3450 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
3451 || TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE)
3452 value = default_conversion (value);
3454 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3455 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3456 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3465 pedwarn ("ANSI C forbids casts to union type");
3466 if (TYPE_NAME (type) != 0)
3468 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
3469 name = IDENTIFIER_POINTER (TYPE_NAME (type));
3471 name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));
3475 return digest_init (type, build (CONSTRUCTOR, type, NULL_TREE,
3476 build_tree_list (field, value)),
3479 error ("cast to union type from type not present in union");
3480 return error_mark_node;
3486 /* If casting to void, avoid the error that would come
3487 from default_conversion in the case of a non-lvalue array. */
3488 if (type == void_type_node)
3489 return build1 (CONVERT_EXPR, type, value);
3491 /* Convert functions and arrays to pointers,
3492 but don't convert any other types. */
3493 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
3494 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE)
3495 value = default_conversion (value);
3496 otype = TREE_TYPE (value);
3498 /* Optionally warn about potentially worrisome casts. */
3501 && TREE_CODE (type) == POINTER_TYPE
3502 && TREE_CODE (otype) == POINTER_TYPE)
3504 if (TYPE_VOLATILE (TREE_TYPE (otype))
3505 && ! TYPE_VOLATILE (TREE_TYPE (type)))
3506 pedwarn ("cast discards `volatile' from pointer target type");
3507 if (TYPE_READONLY (TREE_TYPE (otype))
3508 && ! TYPE_READONLY (TREE_TYPE (type)))
3509 pedwarn ("cast discards `const' from pointer target type");
3512 /* Warn about possible alignment problems. */
3513 if (STRICT_ALIGNMENT && warn_cast_align
3514 && TREE_CODE (type) == POINTER_TYPE
3515 && TREE_CODE (otype) == POINTER_TYPE
3516 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3517 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3518 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3519 warning ("cast increases required alignment of target type");
3521 if (TREE_CODE (type) == INTEGER_TYPE
3522 && TREE_CODE (otype) == POINTER_TYPE
3523 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3524 && !TREE_CONSTANT (value))
3525 warning ("cast from pointer to integer of different size");
3527 if (TREE_CODE (type) == POINTER_TYPE
3528 && TREE_CODE (otype) == INTEGER_TYPE
3529 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3531 /* Don't warn about converting 0 to pointer,
3532 provided the 0 was explicit--not cast or made by folding. */
3533 && !(TREE_CODE (value) == INTEGER_CST && integer_zerop (value))
3535 /* Don't warn about converting any constant. */
3536 && !TREE_CONSTANT (value))
3537 warning ("cast to pointer from integer of different size");
3540 value = convert (type, value);
3542 /* Ignore any integer overflow caused by the cast. */
3543 if (TREE_CODE (value) == INTEGER_CST)
3545 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3546 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3550 /* Pedantically, don't ley (void *) (FOO *) 0 be a null pointer constant. */
3551 if (pedantic && TREE_CODE (value) == INTEGER_CST
3552 && TREE_CODE (expr) == INTEGER_CST
3553 && TREE_CODE (TREE_TYPE (expr)) != INTEGER_TYPE)
3554 value = non_lvalue (value);
3556 /* If pedantic, don't let a cast be an lvalue. */
3557 if (value == expr && pedantic)
3558 value = non_lvalue (value);
3563 /* Build an assignment expression of lvalue LHS from value RHS.
3564 MODIFYCODE is the code for a binary operator that we use
3565 to combine the old value of LHS with RHS to get the new value.
3566 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3569 build_modify_expr (lhs, modifycode, rhs)
3571 enum tree_code modifycode;
3573 register tree result;
3575 tree lhstype = TREE_TYPE (lhs);
3576 tree olhstype = lhstype;
3578 /* Types that aren't fully specified cannot be used in assignments. */
3579 lhs = require_complete_type (lhs);
3581 /* Avoid duplicate error messages from operands that had errors. */
3582 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3583 return error_mark_node;
3585 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3586 /* Do not use STRIP_NOPS here. We do not want an enumerator
3587 whose value is 0 to count as a null pointer constant. */
3588 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3589 rhs = TREE_OPERAND (rhs, 0);
3593 /* Handle control structure constructs used as "lvalues". */
3595 switch (TREE_CODE (lhs))
3597 /* Handle (a, b) used as an "lvalue". */
3599 pedantic_lvalue_warning (COMPOUND_EXPR);
3600 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
3602 if (TREE_CODE (newrhs) == ERROR_MARK)
3603 return error_mark_node;
3604 return build (COMPOUND_EXPR, lhstype,
3605 TREE_OPERAND (lhs, 0), newrhs);
3607 /* Handle (a ? b : c) used as an "lvalue". */
3609 pedantic_lvalue_warning (COND_EXPR);
3610 rhs = save_expr (rhs);
3612 /* Produce (a ? (b = rhs) : (c = rhs))
3613 except that the RHS goes through a save-expr
3614 so the code to compute it is only emitted once. */
3616 = build_conditional_expr (TREE_OPERAND (lhs, 0),
3617 build_modify_expr (TREE_OPERAND (lhs, 1),
3619 build_modify_expr (TREE_OPERAND (lhs, 2),
3621 if (TREE_CODE (cond) == ERROR_MARK)
3623 /* Make sure the code to compute the rhs comes out
3624 before the split. */
3625 return build (COMPOUND_EXPR, TREE_TYPE (lhs),
3626 /* But cast it to void to avoid an "unused" error. */
3627 convert (void_type_node, rhs), cond);
3631 /* If a binary op has been requested, combine the old LHS value with the RHS
3632 producing the value we should actually store into the LHS. */
3634 if (modifycode != NOP_EXPR)
3636 lhs = stabilize_reference (lhs);
3637 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3640 /* Handle a cast used as an "lvalue".
3641 We have already performed any binary operator using the value as cast.
3642 Now convert the result to the cast type of the lhs,
3643 and then true type of the lhs and store it there;
3644 then convert result back to the cast type to be the value
3645 of the assignment. */
3647 switch (TREE_CODE (lhs))
3652 case FIX_TRUNC_EXPR:
3653 case FIX_FLOOR_EXPR:
3654 case FIX_ROUND_EXPR:
3656 if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
3657 || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE)
3658 newrhs = default_conversion (newrhs);
3660 tree inner_lhs = TREE_OPERAND (lhs, 0);
3662 result = build_modify_expr (inner_lhs, NOP_EXPR,
3663 convert (TREE_TYPE (inner_lhs),
3664 convert (lhstype, newrhs)));
3665 if (TREE_CODE (result) == ERROR_MARK)
3667 pedantic_lvalue_warning (CONVERT_EXPR);
3668 return convert (TREE_TYPE (lhs), result);
3672 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3673 Reject anything strange now. */
3675 if (!lvalue_or_else (lhs, "assignment"))
3676 return error_mark_node;
3678 /* Warn about storing in something that is `const'. */
3680 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3681 || ((TREE_CODE (lhstype) == RECORD_TYPE
3682 || TREE_CODE (lhstype) == UNION_TYPE)
3683 && C_TYPE_FIELDS_READONLY (lhstype)))
3684 readonly_warning (lhs, "assignment");
3686 /* If storing into a structure or union member,
3687 it has probably been given type `int'.
3688 Compute the type that would go with
3689 the actual amount of storage the member occupies. */
3691 if (TREE_CODE (lhs) == COMPONENT_REF
3692 && (TREE_CODE (lhstype) == INTEGER_TYPE
3693 || TREE_CODE (lhstype) == REAL_TYPE
3694 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3695 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3697 /* If storing in a field that is in actuality a short or narrower than one,
3698 we must store in the field in its actual type. */
3700 if (lhstype != TREE_TYPE (lhs))
3702 lhs = copy_node (lhs);
3703 TREE_TYPE (lhs) = lhstype;
3706 /* Convert new value to destination type. */
3708 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
3709 NULL_TREE, NULL_TREE, 0);
3710 if (TREE_CODE (newrhs) == ERROR_MARK)
3711 return error_mark_node;
3713 result = build (MODIFY_EXPR, lhstype, lhs, newrhs);
3714 TREE_SIDE_EFFECTS (result) = 1;
3716 /* If we got the LHS in a different type for storing in,
3717 convert the result back to the nominal type of LHS
3718 so that the value we return always has the same type
3719 as the LHS argument. */
3721 if (olhstype == TREE_TYPE (result))
3723 return convert_for_assignment (olhstype, result, "assignment",
3724 NULL_TREE, NULL_TREE, 0);
3727 /* Convert value RHS to type TYPE as preparation for an assignment
3728 to an lvalue of type TYPE.
3729 The real work of conversion is done by `convert'.
3730 The purpose of this function is to generate error messages
3731 for assignments that are not allowed in C.
3732 ERRTYPE is a string to use in error messages:
3733 "assignment", "return", etc. If it is null, this is parameter passing
3734 for a function call (and different error messages are output). Otherwise,
3735 it may be a name stored in the spelling stack and interpreted by
3738 FUNNAME is the name of the function being called,
3739 as an IDENTIFIER_NODE, or null.
3740 PARMNUM is the number of the argument, for printing in error messages. */
3743 convert_for_assignment (type, rhs, errtype, fundecl, funname, parmnum)
3746 tree fundecl, funname;
3749 register enum tree_code codel = TREE_CODE (type);
3750 register tree rhstype;
3751 register enum tree_code coder;
3753 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3754 /* Do not use STRIP_NOPS here. We do not want an enumerator
3755 whose value is 0 to count as a null pointer constant. */
3756 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3757 rhs = TREE_OPERAND (rhs, 0);
3759 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
3760 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
3761 rhs = default_conversion (rhs);
3763 rhstype = TREE_TYPE (rhs);
3764 coder = TREE_CODE (rhstype);
3766 if (coder == ERROR_MARK)
3767 return error_mark_node;
3769 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3771 overflow_warning (rhs);
3772 /* Check for Objective-C protocols. This will issue a warning if
3773 there are protocol violations. No need to use the return value. */
3774 maybe_objc_comptypes (type, rhstype, 0);
3778 if (coder == VOID_TYPE)
3780 error ("void value not ignored as it ought to be");
3781 return error_mark_node;
3783 /* Arithmetic types all interconvert, and enum is treated like int. */
3784 if ((codel == INTEGER_TYPE || codel == REAL_TYPE || codel == ENUMERAL_TYPE
3785 || codel == COMPLEX_TYPE)
3787 (coder == INTEGER_TYPE || coder == REAL_TYPE || coder == ENUMERAL_TYPE
3788 || codel == COMPLEX_TYPE))
3789 return convert_and_check (type, rhs);
3790 /* Conversion to a union from its member types. */
3791 else if (codel == UNION_TYPE)
3794 for (memb_types = TYPE_FIELDS (type); memb_types;
3795 memb_types = TREE_CHAIN (memb_types))
3797 if (comptypes (TREE_TYPE (memb_types), TREE_TYPE (rhs)))
3800 && !(fundecl != 0 && DECL_IN_SYSTEM_HEADER (fundecl)))
3801 pedwarn ("ANSI C prohibits argument conversion to union type");
3802 return build1 (NOP_EXPR, type, rhs);
3804 else if (coder == POINTER_TYPE
3805 && TREE_CODE (TREE_TYPE (memb_types)) == POINTER_TYPE)
3807 tree memb_type = TREE_TYPE (memb_types);
3808 register tree ttl = TREE_TYPE (memb_type);
3809 register tree ttr = TREE_TYPE (rhstype);
3811 /* Any non-function converts to a [const][volatile] void *
3812 and vice versa; otherwise, targets must be the same.
3813 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
3814 if (TYPE_MAIN_VARIANT (ttl) == void_type_node
3815 || TYPE_MAIN_VARIANT (ttr) == void_type_node
3816 || comp_target_types (memb_type, rhstype))
3818 /* Const and volatile mean something different for function types,
3819 so the usual warnings are not appropriate. */
3820 if (TREE_CODE (ttr) != FUNCTION_TYPE
3821 || TREE_CODE (ttl) != FUNCTION_TYPE)
3823 if (! TYPE_READONLY (ttl) && TYPE_READONLY (ttr))
3824 warn_for_assignment ("%s discards `const' from pointer target type",
3825 get_spelling (errtype), funname, parmnum);
3826 if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr))
3827 warn_for_assignment ("%s discards `volatile' from pointer target type",
3828 get_spelling (errtype), funname, parmnum);
3832 /* Because const and volatile on functions are restrictions
3833 that say the function will not do certain things,
3834 it is okay to use a const or volatile function
3835 where an ordinary one is wanted, but not vice-versa. */
3836 if (TYPE_READONLY (ttl) && ! TYPE_READONLY (ttr))
3837 warn_for_assignment ("%s makes `const *' function pointer from non-const",
3838 get_spelling (errtype), funname, parmnum);
3839 if (TYPE_VOLATILE (ttl) && ! TYPE_VOLATILE (ttr))
3840 warn_for_assignment ("%s makes `volatile *' function pointer from non-volatile",
3841 get_spelling (errtype), funname, parmnum);
3844 && !(fundecl != 0 && DECL_IN_SYSTEM_HEADER (fundecl)))
3845 pedwarn ("ANSI C prohibits argument conversion to union type");
3846 return build1 (NOP_EXPR, type, rhs);
3851 /* Conversions among pointers */
3852 else if (codel == POINTER_TYPE && coder == POINTER_TYPE)
3854 register tree ttl = TREE_TYPE (type);
3855 register tree ttr = TREE_TYPE (rhstype);
3857 /* Any non-function converts to a [const][volatile] void *
3858 and vice versa; otherwise, targets must be the same.
3859 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
3860 if (TYPE_MAIN_VARIANT (ttl) == void_type_node
3861 || TYPE_MAIN_VARIANT (ttr) == void_type_node
3862 || comp_target_types (type, rhstype)
3863 || (unsigned_type (TYPE_MAIN_VARIANT (ttl))
3864 == unsigned_type (TYPE_MAIN_VARIANT (ttr))))
3867 && ((TYPE_MAIN_VARIANT (ttl) == void_type_node
3868 && TREE_CODE (ttr) == FUNCTION_TYPE)
3870 (TYPE_MAIN_VARIANT (ttr) == void_type_node
3871 /* Check TREE_CODE to catch cases like (void *) (char *) 0
3872 which are not ANSI null ptr constants. */
3873 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
3874 && TREE_CODE (ttl) == FUNCTION_TYPE)))
3875 warn_for_assignment ("ANSI forbids %s between function pointer and `void *'",
3876 get_spelling (errtype), funname, parmnum);
3877 /* Const and volatile mean something different for function types,
3878 so the usual warnings are not appropriate. */
3879 else if (TREE_CODE (ttr) != FUNCTION_TYPE
3880 || TREE_CODE (ttl) != FUNCTION_TYPE)
3882 if (! TYPE_READONLY (ttl) && TYPE_READONLY (ttr))
3883 warn_for_assignment ("%s discards `const' from pointer target type",
3884 get_spelling (errtype), funname, parmnum);
3885 else if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr))
3886 warn_for_assignment ("%s discards `volatile' from pointer target type",
3887 get_spelling (errtype), funname, parmnum);
3888 /* If this is not a case of ignoring a mismatch in signedness,
3890 else if (TYPE_MAIN_VARIANT (ttl) == void_type_node
3891 || TYPE_MAIN_VARIANT (ttr) == void_type_node
3892 || comp_target_types (type, rhstype))
3894 /* If there is a mismatch, do warn. */
3896 warn_for_assignment ("pointer targets in %s differ in signedness",
3897 get_spelling (errtype), funname, parmnum);
3901 /* Because const and volatile on functions are restrictions
3902 that say the function will not do certain things,
3903 it is okay to use a const or volatile function
3904 where an ordinary one is wanted, but not vice-versa. */
3905 if (TYPE_READONLY (ttl) && ! TYPE_READONLY (ttr))
3906 warn_for_assignment ("%s makes `const *' function pointer from non-const",
3907 get_spelling (errtype), funname, parmnum);
3908 if (TYPE_VOLATILE (ttl) && ! TYPE_VOLATILE (ttr))
3909 warn_for_assignment ("%s makes `volatile *' function pointer from non-volatile",
3910 get_spelling (errtype), funname, parmnum);
3914 warn_for_assignment ("%s from incompatible pointer type",
3915 get_spelling (errtype), funname, parmnum);
3916 return convert (type, rhs);
3918 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
3920 /* An explicit constant 0 can convert to a pointer,
3921 or one that results from arithmetic, even including
3922 a cast to integer type. */
3923 if (! (TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
3925 ! (TREE_CODE (rhs) == NOP_EXPR
3926 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
3927 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
3928 && integer_zerop (TREE_OPERAND (rhs, 0))))
3930 warn_for_assignment ("%s makes pointer from integer without a cast",
3931 get_spelling (errtype), funname, parmnum);
3932 return convert (type, rhs);
3934 return null_pointer_node;
3936 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
3938 warn_for_assignment ("%s makes integer from pointer without a cast",
3939 get_spelling (errtype), funname, parmnum);
3940 return convert (type, rhs);
3947 tree selector = maybe_building_objc_message_expr ();
3949 if (selector && parmnum > 2)
3950 error ("incompatible type for argument %d of `%s'",
3951 parmnum - 2, IDENTIFIER_POINTER (selector));
3953 error ("incompatible type for argument %d of `%s'",
3954 parmnum, IDENTIFIER_POINTER (funname));
3957 error ("incompatible type for argument %d of indirect function call",
3961 error ("incompatible types in %s", get_spelling (errtype));
3963 return error_mark_node;
3966 /* Print a warning using MSG.
3967 It gets OPNAME as its one parameter.
3968 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
3969 FUNCTION and ARGNUM are handled specially if we are building an
3970 Objective-C selector. */
3973 warn_for_assignment (msg, opname, function, argnum)
3979 static char argstring[] = "passing arg %d of `%s'";
3980 static char argnofun[] = "passing arg %d";
3984 tree selector = maybe_building_objc_message_expr ();
3986 if (selector && argnum > 2)
3988 function = selector;
3993 /* Function name is known; supply it. */
3994 opname = (char *) alloca (IDENTIFIER_LENGTH (function)
3995 + sizeof (argstring) + 25 /*%d*/ + 1);
3996 sprintf (opname, argstring, argnum, IDENTIFIER_POINTER (function));
4000 /* Function name unknown (call through ptr); just give arg number. */
4001 opname = (char *) alloca (sizeof (argnofun) + 25 /*%d*/ + 1);
4002 sprintf (opname, argnofun, argnum);
4005 pedwarn (msg, opname);
4008 /* Return nonzero if VALUE is a valid constant-valued expression
4009 for use in initializing a static variable; one that can be an
4010 element of a "constant" initializer.
4012 Return null_pointer_node if the value is absolute;
4013 if it is relocatable, return the variable that determines the relocation.
4014 We assume that VALUE has been folded as much as possible;
4015 therefore, we do not need to check for such things as
4016 arithmetic-combinations of integers. */
4019 initializer_constant_valid_p (value, endtype)
4023 switch (TREE_CODE (value))
4026 return TREE_STATIC (value) ? null_pointer_node : 0;
4032 return null_pointer_node;
4035 return TREE_OPERAND (value, 0);
4037 case NON_LVALUE_EXPR:
4038 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4042 /* Allow conversions between pointer types. */
4043 if (TREE_CODE (TREE_TYPE (value)) == POINTER_TYPE
4044 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == POINTER_TYPE)
4045 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4046 /* Allow conversions between real types. */
4047 if (TREE_CODE (TREE_TYPE (value)) == REAL_TYPE
4048 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == REAL_TYPE)
4049 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4050 /* Allow length-preserving conversions between integer types. */
4051 if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
4052 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE
4053 && tree_int_cst_equal (TYPE_SIZE (TREE_TYPE (value)),
4054 TYPE_SIZE (TREE_TYPE (TREE_OPERAND (value, 0)))))
4055 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4056 /* Allow conversions between integer types only if explicit value. */
4057 if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
4058 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE)
4060 tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0),
4062 if (inner == null_pointer_node)
4063 return null_pointer_node;
4066 /* Allow (int) &foo provided int is as wide as a pointer. */
4067 if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
4068 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == POINTER_TYPE
4069 && ! tree_int_cst_lt (TYPE_SIZE (TREE_TYPE (value)),
4070 TYPE_SIZE (TREE_TYPE (TREE_OPERAND (value, 0)))))
4071 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
4073 /* Allow conversions to union types if the value inside is okay. */
4074 if (TREE_CODE (TREE_TYPE (value)) == UNION_TYPE)
4075 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
4080 if (TREE_CODE (endtype) == INTEGER_TYPE
4081 && TYPE_PRECISION (endtype) < POINTER_SIZE)
4084 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
4086 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
4088 /* If either term is absolute, use the other terms relocation. */
4089 if (valid0 == null_pointer_node)
4091 if (valid1 == null_pointer_node)
4097 if (TREE_CODE (endtype) == INTEGER_TYPE
4098 && TYPE_PRECISION (endtype) < POINTER_SIZE)
4101 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
4103 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
4105 /* Win if second argument is absolute. */
4106 if (valid1 == null_pointer_node)
4108 /* Win if both arguments have the same relocation.
4109 Then the value is absolute. */
4110 if (valid0 == valid1)
4111 return null_pointer_node;
4119 /* If VALUE is a compound expr all of whose expressions are constant, then
4120 return its value. Otherwise, return error_mark_node.
4122 This is for handling COMPOUND_EXPRs as initializer elements
4123 which is allowed with a warning when -pedantic is specified. */
4126 valid_compound_expr_initializer (value, endtype)
4130 if (TREE_CODE (value) == COMPOUND_EXPR)
4132 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4134 return error_mark_node;
4135 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4138 else if (! TREE_CONSTANT (value)
4139 && ! initializer_constant_valid_p (value, endtype))
4140 return error_mark_node;
4145 /* Perform appropriate conversions on the initial value of a variable,
4146 store it in the declaration DECL,
4147 and print any error messages that are appropriate.
4148 If the init is invalid, store an ERROR_MARK. */
4151 store_init_value (decl, init)
4154 register tree value, type;
4156 /* If variable's type was invalidly declared, just ignore it. */
4158 type = TREE_TYPE (decl);
4159 if (TREE_CODE (type) == ERROR_MARK)
4162 /* Digest the specified initializer into an expression. */
4164 value = digest_init (type, init, TREE_STATIC (decl),
4165 TREE_STATIC (decl) || pedantic);
4167 /* Store the expression if valid; else report error. */
4170 /* Note that this is the only place we can detect the error
4171 in a case such as struct foo bar = (struct foo) { x, y };
4172 where there is one initial value which is a constructor expression. */
4173 if (value == error_mark_node)
4175 else if (TREE_STATIC (decl) && ! TREE_CONSTANT (value))
4177 error ("initializer for static variable is not constant");
4178 value = error_mark_node;
4180 else if (TREE_STATIC (decl)
4181 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
4183 error ("initializer for static variable uses complicated arithmetic");
4184 value = error_mark_node;
4188 if (pedantic && TREE_CODE (value) == CONSTRUCTOR)
4190 if (! TREE_CONSTANT (value))
4191 pedwarn ("aggregate initializer is not constant");
4192 else if (! TREE_STATIC (value))
4193 pedwarn ("aggregate initializer uses complicated arithmetic");
4198 DECL_INITIAL (decl) = value;
4200 /* ANSI wants warnings about out-of-range constant initializers. */
4201 STRIP_TYPE_NOPS (value);
4202 constant_expression_warning (value);
4205 /* Methods for storing and printing names for error messages. */
4207 /* Implement a spelling stack that allows components of a name to be pushed
4208 and popped. Each element on the stack is this structure. */
4220 #define SPELLING_STRING 1
4221 #define SPELLING_MEMBER 2
4222 #define SPELLING_BOUNDS 3
4224 static struct spelling *spelling; /* Next stack element (unused). */
4225 static struct spelling *spelling_base; /* Spelling stack base. */
4226 static int spelling_size; /* Size of the spelling stack. */
4228 /* Macros to save and restore the spelling stack around push_... functions.
4229 Alternative to SAVE_SPELLING_STACK. */
4231 #define SPELLING_DEPTH() (spelling - spelling_base)
4232 #define RESTORE_SPELLING_DEPTH(depth) (spelling = spelling_base + depth)
4234 /* Save and restore the spelling stack around arbitrary C code. */
4236 #define SAVE_SPELLING_DEPTH(code) \
4238 int __depth = SPELLING_DEPTH (); \
4240 RESTORE_SPELLING_DEPTH (__depth); \
4243 /* Push an element on the spelling stack with type KIND and assign VALUE
4246 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4248 int depth = SPELLING_DEPTH (); \
4250 if (depth >= spelling_size) \
4252 spelling_size += 10; \
4253 if (spelling_base == 0) \
4255 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4258 = (struct spelling *) xrealloc (spelling_base, \
4259 spelling_size * sizeof (struct spelling)); \
4260 RESTORE_SPELLING_DEPTH (depth); \
4263 spelling->kind = (KIND); \
4264 spelling->MEMBER = (VALUE); \
4268 /* Push STRING on the stack. Printed literally. */
4271 push_string (string)
4274 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4277 /* Push a member name on the stack. Printed as '.' STRING. */
4280 push_member_name (decl)
4285 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4286 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4289 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4292 push_array_bounds (bounds)
4295 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4298 /* Compute the maximum size in bytes of the printed spelling. */
4303 register int size = 0;
4304 register struct spelling *p;
4306 for (p = spelling_base; p < spelling; p++)
4308 if (p->kind == SPELLING_BOUNDS)
4311 size += strlen (p->u.s) + 1;
4317 /* Print the spelling to BUFFER and return it. */
4320 print_spelling (buffer)
4321 register char *buffer;
4323 register char *d = buffer;
4325 register struct spelling *p;
4327 for (p = spelling_base; p < spelling; p++)
4328 if (p->kind == SPELLING_BOUNDS)
4330 sprintf (d, "[%d]", p->u.i);
4335 if (p->kind == SPELLING_MEMBER)
4337 for (s = p->u.s; *d = *s++; d++)
4344 /* Provide a means to pass component names derived from the spelling stack. */
4346 char initialization_message;
4348 /* Interpret the spelling of the given ERRTYPE message. */
4351 get_spelling (errtype)
4354 static char *buffer;
4355 static int size = -1;
4357 if (errtype == &initialization_message)
4359 /* Avoid counting chars */
4360 static char message[] = "initialization of `%s'";
4361 register int needed = sizeof (message) + spelling_length () + 1;
4365 buffer = (char *) xmalloc (size = needed);
4367 buffer = (char *) xrealloc (buffer, size = needed);
4369 temp = (char *) alloca (needed);
4370 sprintf (buffer, message, print_spelling (temp));
4377 /* Issue an error message for a bad initializer component.
4378 FORMAT describes the message. OFWHAT is the name for the component.
4379 LOCAL is a format string for formatting the insertion of the name
4382 If OFWHAT is null, the component name is stored on the spelling stack.
4383 If the component name is a null string, then LOCAL is omitted entirely. */
4386 error_init (format, local, ofwhat)
4387 char *format, *local, *ofwhat;
4392 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4393 buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2);
4396 sprintf (buffer, local, ofwhat);
4400 error (format, buffer);
4403 /* Issue a pedantic warning for a bad initializer component.
4404 FORMAT describes the message. OFWHAT is the name for the component.
4405 LOCAL is a format string for formatting the insertion of the name
4408 If OFWHAT is null, the component name is stored on the spelling stack.
4409 If the component name is a null string, then LOCAL is omitted entirely. */
4412 pedwarn_init (format, local, ofwhat)
4413 char *format, *local, *ofwhat;
4418 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4419 buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2);
4422 sprintf (buffer, local, ofwhat);
4426 pedwarn (format, buffer);
4429 /* Digest the parser output INIT as an initializer for type TYPE.
4430 Return a C expression of type TYPE to represent the initial value.
4432 The arguments REQUIRE_CONSTANT and CONSTRUCTOR_CONSTANT request errors
4433 if non-constant initializers or elements are seen. CONSTRUCTOR_CONSTANT
4434 applies only to elements of constructors. */
4437 digest_init (type, init, require_constant, constructor_constant)
4439 int require_constant, constructor_constant;
4441 enum tree_code code = TREE_CODE (type);
4442 tree inside_init = init;
4444 if (init == error_mark_node)
4447 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4448 /* Do not use STRIP_NOPS here. We do not want an enumerator
4449 whose value is 0 to count as a null pointer constant. */
4450 if (TREE_CODE (init) == NON_LVALUE_EXPR)
4451 inside_init = TREE_OPERAND (init, 0);
4453 /* Initialization of an array of chars from a string constant
4454 optionally enclosed in braces. */
4456 if (code == ARRAY_TYPE)
4458 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4459 if ((typ1 == char_type_node
4460 || typ1 == signed_char_type_node
4461 || typ1 == unsigned_char_type_node
4462 || typ1 == unsigned_wchar_type_node
4463 || typ1 == signed_wchar_type_node)
4464 && ((inside_init && TREE_CODE (inside_init) == STRING_CST)))
4466 if (TREE_TYPE (inside_init) == type)
4469 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4471 && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node))
4473 error_init ("char-array%s initialized from wide string",
4475 return error_mark_node;
4477 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4479 && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node))
4481 error_init ("int-array%s initialized from non-wide string",
4483 return error_mark_node;
4486 TREE_TYPE (inside_init) = type;
4487 if (TYPE_DOMAIN (type) != 0
4488 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
4490 register int size = TREE_INT_CST_LOW (TYPE_SIZE (type));
4491 size = (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
4492 /* Subtract 1 (or sizeof (wchar_t))
4493 because it's ok to ignore the terminating null char
4494 that is counted in the length of the constant. */
4495 if (size < TREE_STRING_LENGTH (inside_init)
4496 - (TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node)
4497 ? TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT
4500 "initializer-string for array of chars%s is too long",
4507 /* Any type can be initialized
4508 from an expression of the same type, optionally with braces. */
4510 if (inside_init && TREE_TYPE (inside_init) != 0
4511 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4512 TYPE_MAIN_VARIANT (type))
4513 || (code == ARRAY_TYPE
4514 && comptypes (TREE_TYPE (inside_init), type))
4515 || (code == POINTER_TYPE
4516 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4517 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE)
4518 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4519 TREE_TYPE (type)))))
4521 if (code == POINTER_TYPE
4522 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4523 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE))
4524 inside_init = default_conversion (inside_init);
4525 else if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4526 && TREE_CODE (inside_init) != CONSTRUCTOR)
4528 error_init ("array%s initialized from non-constant array expression",
4530 return error_mark_node;
4533 if (optimize && TREE_READONLY (inside_init)
4534 && TREE_CODE (inside_init) == VAR_DECL)
4535 inside_init = decl_constant_value (inside_init);
4537 /* Compound expressions can only occur here if -pedantic or
4538 -pedantic-errors is specified. In the later case, we always want
4539 an error. In the former case, we simply want a warning. */
4540 if (require_constant && pedantic
4541 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4544 = valid_compound_expr_initializer (inside_init,
4545 TREE_TYPE (inside_init));
4546 if (inside_init == error_mark_node)
4547 error_init ("initializer element%s is not constant",
4550 pedwarn_init ("initializer element%s is not constant",
4552 if (flag_pedantic_errors)
4553 inside_init = error_mark_node;
4555 else if (require_constant && ! TREE_CONSTANT (inside_init))
4557 error_init ("initializer element%s is not constant",
4559 inside_init = error_mark_node;
4561 else if (require_constant
4562 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4564 error_init ("initializer element%s is not computable at load time",
4566 inside_init = error_mark_node;
4572 /* Handle scalar types, including conversions. */
4574 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4575 || code == ENUMERAL_TYPE || code == COMPLEX_TYPE)
4577 /* Note that convert_for_assignment calls default_conversion
4578 for arrays and functions. We must not call it in the
4579 case where inside_init is a null pointer constant. */
4581 = convert_for_assignment (type, init, "initialization",
4582 NULL_TREE, NULL_TREE, 0);
4584 if (require_constant && ! TREE_CONSTANT (inside_init))
4586 error_init ("initializer element%s is not constant",
4588 inside_init = error_mark_node;
4590 else if (require_constant
4591 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4593 error_init ("initializer element%s is not computable at load time",
4595 inside_init = error_mark_node;
4601 /* Come here only for records and arrays. */
4603 if (TYPE_SIZE (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4605 error_init ("variable-sized object%s may not be initialized",
4607 return error_mark_node;
4610 /* Traditionally, you can write struct foo x = 0;
4611 and it initializes the first element of x to 0. */
4612 if (flag_traditional)
4614 tree top = 0, prev = 0;
4615 while (TREE_CODE (type) == RECORD_TYPE
4616 || TREE_CODE (type) == ARRAY_TYPE
4617 || TREE_CODE (type) == QUAL_UNION_TYPE
4618 || TREE_CODE (type) == UNION_TYPE)
4620 tree temp = build (CONSTRUCTOR, type, NULL_TREE, NULL_TREE);
4624 TREE_OPERAND (prev, 1) = build_tree_list (NULL_TREE, temp);
4626 if (TREE_CODE (type) == ARRAY_TYPE)
4627 type = TREE_TYPE (type);
4628 else if (TYPE_FIELDS (type))
4629 type = TREE_TYPE (TYPE_FIELDS (type));
4632 error_init ("invalid initializer%s", " for `%s'", NULL);
4633 return error_mark_node;
4636 TREE_OPERAND (prev, 1)
4637 = build_tree_list (NULL_TREE,
4638 digest_init (type, init, require_constant,
4639 constructor_constant));
4642 error_init ("invalid initializer%s", " for `%s'", NULL);
4643 return error_mark_node;
4646 /* Handle initializers that use braces. */
4648 static void output_init_element ();
4649 static void output_pending_init_elements ();
4650 static void check_init_type_bitfields ();
4652 /* Type of object we are accumulating a constructor for.
4653 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4654 static tree constructor_type;
4656 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4658 static tree constructor_fields;
4660 /* For an ARRAY_TYPE, this is the specified index
4661 at which to store the next element we get.
4662 This is a special INTEGER_CST node that we modify in place. */
4663 static tree constructor_index;
4665 /* For an ARRAY_TYPE, this is the end index of the range
4666 to intitialize with the next element, or NULL in the ordinary case
4667 where the element is used just once. */
4668 static tree constructor_range_end;
4670 /* For an ARRAY_TYPE, this is the maximum index. */
4671 static tree constructor_max_index;
4673 /* For a RECORD_TYPE, this is the first field not yet written out. */
4674 static tree constructor_unfilled_fields;
4676 /* For an ARRAY_TYPE, this is the index of the first element
4677 not yet written out.
4678 This is a special INTEGER_CST node that we modify in place. */
4679 static tree constructor_unfilled_index;
4681 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4682 This is so we can generate gaps between fields, when appropriate.
4683 This is a special INTEGER_CST node that we modify in place. */
4684 static tree constructor_bit_index;
4686 /* If we are saving up the elements rather than allocating them,
4687 this is the list of elements so far (in reverse order,
4688 most recent first). */
4689 static tree constructor_elements;
4691 /* 1 if so far this constructor's elements are all compile-time constants. */
4692 static int constructor_constant;
4694 /* 1 if so far this constructor's elements are all valid address constants. */
4695 static int constructor_simple;
4697 /* 1 if this constructor is erroneous so far. */
4698 static int constructor_erroneous;
4700 /* 1 if have called defer_addressed_constants. */
4701 static int constructor_subconstants_deferred;
4703 /* List of pending elements at this constructor level.
4704 These are elements encountered out of order
4705 which belong at places we haven't reached yet in actually
4706 writing the output. */
4707 static tree constructor_pending_elts;
4709 /* The SPELLING_DEPTH of this constructor. */
4710 static int constructor_depth;
4712 /* 0 if implicitly pushing constructor levels is allowed. */
4713 int constructor_no_implicit = 0; /* 0 for C; 1 for some other languages. */
4715 /* 1 if this constructor level was entered implicitly. */
4716 static int constructor_implicit;
4718 static int require_constant_value;
4719 static int require_constant_elements;
4721 /* 1 if it is ok to output this constructor as we read it.
4722 0 means must accumulate a CONSTRUCTOR expression. */
4723 static int constructor_incremental;
4725 /* DECL node for which an initializer is being read.
4726 0 means we are reading a constructor expression
4727 such as (struct foo) {...}. */
4728 static tree constructor_decl;
4730 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4731 static char *constructor_asmspec;
4733 /* Nonzero if this is an initializer for a top-level decl. */
4734 static int constructor_top_level;
4736 /* When we finish reading a constructor expression
4737 (constructor_decl is 0), the CONSTRUCTOR goes here. */
4738 static tree constructor_result;
4740 /* This stack has a level for each implicit or explicit level of
4741 structuring in the initializer, including the outermost one. It
4742 saves the values of most of the variables above. */
4744 struct constructor_stack
4746 struct constructor_stack *next;
4752 tree unfilled_index;
4753 tree unfilled_fields;
4759 /* If nonzero, this value should replace the entire
4760 constructor at this level. */
4761 tree replacement_value;
4770 struct constructor_stack *constructor_stack;
4772 /* This stack records separate initializers that are nested.
4773 Nested initializers can't happen in ANSI C, but GNU C allows them
4774 in cases like { ... (struct foo) { ... } ... }. */
4776 struct initializer_stack
4778 struct initializer_stack *next;
4781 struct constructor_stack *constructor_stack;
4782 struct spelling *spelling;
4783 struct spelling *spelling_base;
4787 char require_constant_value;
4788 char require_constant_elements;
4792 struct initializer_stack *initializer_stack;
4794 /* Prepare to parse and output the initializer for variable DECL. */
4797 start_init (decl, asmspec_tree, top_level)
4803 struct initializer_stack *p
4804 = (struct initializer_stack *) xmalloc (sizeof (struct initializer_stack));
4808 asmspec = TREE_STRING_POINTER (asmspec_tree);
4810 p->decl = constructor_decl;
4811 p->asmspec = constructor_asmspec;
4812 p->incremental = constructor_incremental;
4813 p->require_constant_value = require_constant_value;
4814 p->require_constant_elements = require_constant_elements;
4815 p->constructor_stack = constructor_stack;
4816 p->spelling = spelling;
4817 p->spelling_base = spelling_base;
4818 p->spelling_size = spelling_size;
4819 p->deferred = constructor_subconstants_deferred;
4820 p->top_level = constructor_top_level;
4821 p->next = initializer_stack;
4822 initializer_stack = p;
4824 constructor_decl = decl;
4825 constructor_incremental = top_level;
4826 constructor_asmspec = asmspec;
4827 constructor_subconstants_deferred = 0;
4828 constructor_top_level = top_level;
4832 require_constant_value = TREE_STATIC (decl);
4833 require_constant_elements
4834 = ((TREE_STATIC (decl) || pedantic)
4835 /* For a scalar, you can always use any value to initialize,
4836 even within braces. */
4837 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4838 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4839 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4840 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4841 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4842 constructor_incremental |= TREE_STATIC (decl);
4846 require_constant_value = 0;
4847 require_constant_elements = 0;
4848 locus = "(anonymous)";
4851 constructor_stack = 0;
4855 RESTORE_SPELLING_DEPTH (0);
4858 push_string (locus);
4864 struct initializer_stack *p = initializer_stack;
4866 /* Output subconstants (string constants, usually)
4867 that were referenced within this initializer and saved up.
4868 Must do this if and only if we called defer_addressed_constants. */
4869 if (constructor_subconstants_deferred)
4870 output_deferred_addressed_constants ();
4872 /* Free the whole constructor stack of this initializer. */
4873 while (constructor_stack)
4875 struct constructor_stack *q = constructor_stack;
4876 constructor_stack = q->next;
4880 /* Pop back to the data of the outer initializer (if any). */
4881 constructor_decl = p->decl;
4882 constructor_asmspec = p->asmspec;
4883 constructor_incremental = p->incremental;
4884 require_constant_value = p->require_constant_value;
4885 require_constant_elements = p->require_constant_elements;
4886 constructor_stack = p->constructor_stack;
4887 spelling = p->spelling;
4888 spelling_base = p->spelling_base;
4889 spelling_size = p->spelling_size;
4890 constructor_subconstants_deferred = p->deferred;
4891 constructor_top_level = p->top_level;
4892 initializer_stack = p->next;
4896 /* Call here when we see the initializer is surrounded by braces.
4897 This is instead of a call to push_init_level;
4898 it is matched by a call to pop_init_level.
4900 TYPE is the type to initialize, for a constructor expression.
4901 For an initializer for a decl, TYPE is zero. */
4904 really_start_incremental_init (type)
4907 struct constructor_stack *p
4908 = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
4911 type = TREE_TYPE (constructor_decl);
4913 /* Turn off constructor_incremental if type is a struct with bitfields.
4914 Do this before the first push, so that the corrected value
4915 is available in finish_init. */
4916 check_init_type_bitfields (type);
4918 p->type = constructor_type;
4919 p->fields = constructor_fields;
4920 p->index = constructor_index;
4921 p->range_end = constructor_range_end;
4922 p->max_index = constructor_max_index;
4923 p->unfilled_index = constructor_unfilled_index;
4924 p->unfilled_fields = constructor_unfilled_fields;
4925 p->bit_index = constructor_bit_index;
4927 p->constant = constructor_constant;
4928 p->simple = constructor_simple;
4929 p->erroneous = constructor_erroneous;
4930 p->pending_elts = constructor_pending_elts;
4931 p->depth = constructor_depth;
4932 p->replacement_value = 0;
4934 p->incremental = constructor_incremental;
4937 constructor_stack = p;
4939 constructor_constant = 1;
4940 constructor_simple = 1;
4941 constructor_depth = SPELLING_DEPTH ();
4942 constructor_elements = 0;
4943 constructor_pending_elts = 0;
4944 constructor_type = type;
4946 if (TREE_CODE (constructor_type) == RECORD_TYPE
4947 || TREE_CODE (constructor_type) == UNION_TYPE)
4949 constructor_fields = TYPE_FIELDS (constructor_type);
4950 constructor_unfilled_fields = constructor_fields;
4951 constructor_bit_index = copy_node (integer_zero_node);
4953 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4955 constructor_range_end = 0;
4956 if (TYPE_DOMAIN (constructor_type))
4958 constructor_max_index
4959 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4961 = copy_node (TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
4964 constructor_index = copy_node (integer_zero_node);
4965 constructor_unfilled_index = copy_node (constructor_index);
4969 /* Handle the case of int x = {5}; */
4970 constructor_fields = constructor_type;
4971 constructor_unfilled_fields = constructor_type;
4974 if (constructor_incremental)
4976 int momentary = suspend_momentary ();
4977 push_obstacks_nochange ();
4978 if (TREE_PERMANENT (constructor_decl))
4979 end_temporary_allocation ();
4980 make_decl_rtl (constructor_decl, constructor_asmspec,
4981 constructor_top_level);
4982 assemble_variable (constructor_decl, constructor_top_level, 0, 1);
4984 resume_momentary (momentary);
4987 if (constructor_incremental)
4989 defer_addressed_constants ();
4990 constructor_subconstants_deferred = 1;
4994 /* Push down into a subobject, for initialization.
4995 If this is for an explicit set of braces, IMPLICIT is 0.
4996 If it is because the next element belongs at a lower level,
5000 push_init_level (implicit)
5003 struct constructor_stack *p;
5005 /* If we've exhausted any levels that didn't have braces,
5007 while (constructor_stack->implicit)
5009 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5010 || TREE_CODE (constructor_type) == UNION_TYPE)
5011 && constructor_fields == 0)
5012 process_init_element (pop_init_level (1));
5013 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5014 && tree_int_cst_lt (constructor_max_index, constructor_index))
5015 process_init_element (pop_init_level (1));
5020 p = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5021 p->type = constructor_type;
5022 p->fields = constructor_fields;
5023 p->index = constructor_index;
5024 p->range_end = constructor_range_end;
5025 p->max_index = constructor_max_index;
5026 p->unfilled_index = constructor_unfilled_index;
5027 p->unfilled_fields = constructor_unfilled_fields;
5028 p->bit_index = constructor_bit_index;
5029 p->elements = constructor_elements;
5030 p->constant = constructor_constant;
5031 p->simple = constructor_simple;
5032 p->erroneous = constructor_erroneous;
5033 p->pending_elts = constructor_pending_elts;
5034 p->depth = constructor_depth;
5035 p->replacement_value = 0;
5036 p->implicit = implicit;
5037 p->incremental = constructor_incremental;
5039 p->next = constructor_stack;
5040 constructor_stack = p;
5042 constructor_constant = 1;
5043 constructor_simple = 1;
5044 constructor_depth = SPELLING_DEPTH ();
5045 constructor_elements = 0;
5046 constructor_pending_elts = 0;
5048 /* Don't die if an entire brace-pair level is superfluous
5049 in the containing level. */
5050 if (constructor_type == 0)
5052 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5053 || TREE_CODE (constructor_type) == UNION_TYPE)
5055 /* Don't die if there are extra init elts at the end. */
5056 if (constructor_fields == 0)
5057 constructor_type = 0;
5060 constructor_type = TREE_TYPE (constructor_fields);
5061 push_member_name (constructor_fields);
5064 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5066 constructor_type = TREE_TYPE (constructor_type);
5067 push_array_bounds (TREE_INT_CST_LOW (constructor_index));
5070 /* Turn off constructor_incremental if type is a struct with bitfields. */
5071 if (constructor_type != 0)
5072 check_init_type_bitfields (constructor_type);
5074 if (constructor_type == 0)
5076 error_init ("extra brace group at end of initializer%s",
5078 constructor_fields = 0;
5079 constructor_unfilled_fields = 0;
5081 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5082 || TREE_CODE (constructor_type) == UNION_TYPE)
5084 constructor_fields = TYPE_FIELDS (constructor_type);
5085 constructor_unfilled_fields = constructor_fields;
5086 constructor_bit_index = copy_node (integer_zero_node);
5088 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5090 constructor_range_end = 0;
5091 if (TYPE_DOMAIN (constructor_type))
5093 constructor_max_index
5094 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5096 = copy_node (TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5099 constructor_index = copy_node (integer_zero_node);
5100 constructor_unfilled_index = copy_node (constructor_index);
5104 warning ("braces around scalar initializer");
5105 constructor_fields = constructor_type;
5106 constructor_unfilled_fields = constructor_type;
5110 /* Don't read a struct incrementally if it has any bitfields,
5111 because the incremental reading code doesn't know how to
5112 handle bitfields yet. */
5115 check_init_type_bitfields (type)
5118 if (TREE_CODE (type) == RECORD_TYPE)
5121 for (tail = TYPE_FIELDS (type); tail;
5122 tail = TREE_CHAIN (tail))
5123 if (DECL_BIT_FIELD (tail)
5124 /* This catches cases like `int foo : 8;'. */
5125 || DECL_MODE (tail) != TYPE_MODE (TREE_TYPE (tail)))
5127 constructor_incremental = 0;
5133 /* At the end of an implicit or explicit brace level,
5134 finish up that level of constructor.
5135 If we were outputting the elements as they are read, return 0
5136 from inner levels (process_init_element ignores that),
5137 but return error_mark_node from the outermost level
5138 (that's what we want to put in DECL_INITIAL).
5139 Otherwise, return a CONSTRUCTOR expression. */
5142 pop_init_level (implicit)
5145 struct constructor_stack *p;
5147 tree constructor = 0;
5151 /* When we come to an explicit close brace,
5152 pop any inner levels that didn't have explicit braces. */
5153 while (constructor_stack->implicit)
5154 process_init_element (pop_init_level (1));
5157 p = constructor_stack;
5159 if (constructor_type != 0)
5160 size = int_size_in_bytes (constructor_type);
5162 /* Now output all pending elements. */
5163 output_pending_init_elements (1);
5165 #if 0 /* c-parse.in warns about {}. */
5166 /* In ANSI, each brace level must have at least one element. */
5167 if (! implicit && pedantic
5168 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5169 ? integer_zerop (constructor_unfilled_index)
5170 : constructor_unfilled_fields == TYPE_FIELDS (constructor_type)))
5171 pedwarn_init ("empty braces in initializer%s", " for `%s'", NULL);
5174 /* Pad out the end of the structure. */
5176 if (p->replacement_value)
5178 /* If this closes a superfluous brace pair,
5179 just pass out the element between them. */
5180 constructor = p->replacement_value;
5181 /* If this is the top level thing within the initializer,
5182 and it's for a variable, then since we already called
5183 assemble_variable, we must output the value now. */
5184 if (p->next == 0 && constructor_decl != 0
5185 && constructor_incremental)
5187 constructor = digest_init (constructor_type, constructor,
5190 /* If initializing an array of unknown size,
5191 determine the size now. */
5192 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5193 && TYPE_DOMAIN (constructor_type) == 0)
5197 push_obstacks_nochange ();
5198 if (TREE_PERMANENT (constructor_type))
5199 end_temporary_allocation ();
5201 /* We shouldn't have an incomplete array type within
5203 if (constructor_stack->next)
5207 = complete_array_type (constructor_type,
5212 size = int_size_in_bytes (constructor_type);
5216 output_constant (constructor, size);
5219 else if (constructor_type == 0)
5221 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5222 && TREE_CODE (constructor_type) != UNION_TYPE
5223 && TREE_CODE (constructor_type) != ARRAY_TYPE
5224 && ! constructor_incremental)
5226 /* A nonincremental scalar initializer--just return
5227 the element, after verifying there is just one. */
5228 if (constructor_elements == 0)
5230 error_init ("empty scalar initializer%s",
5232 constructor = error_mark_node;
5234 else if (TREE_CHAIN (constructor_elements) != 0)
5236 error_init ("extra elements in scalar initializer%s",
5238 constructor = TREE_VALUE (constructor_elements);
5241 constructor = TREE_VALUE (constructor_elements);
5243 else if (! constructor_incremental)
5245 if (constructor_erroneous)
5246 constructor = error_mark_node;
5249 int momentary = suspend_momentary ();
5251 constructor = build (CONSTRUCTOR, constructor_type, NULL_TREE,
5252 nreverse (constructor_elements));
5253 if (constructor_constant)
5254 TREE_CONSTANT (constructor) = 1;
5255 if (constructor_constant && constructor_simple)
5256 TREE_STATIC (constructor) = 1;
5258 resume_momentary (momentary);
5264 int momentary = suspend_momentary ();
5266 if (TREE_CODE (constructor_type) == RECORD_TYPE
5267 || TREE_CODE (constructor_type) == UNION_TYPE)
5269 /* Find the offset of the end of that field. */
5270 filled = size_binop (CEIL_DIV_EXPR,
5271 constructor_bit_index,
5272 size_int (BITS_PER_UNIT));
5274 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5276 /* If initializing an array of unknown size,
5277 determine the size now. */
5278 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5279 && TYPE_DOMAIN (constructor_type) == 0)
5282 = size_binop (MINUS_EXPR,
5283 constructor_unfilled_index,
5286 push_obstacks_nochange ();
5287 if (TREE_PERMANENT (constructor_type))
5288 end_temporary_allocation ();
5289 maxindex = copy_node (maxindex);
5290 TYPE_DOMAIN (constructor_type) = build_index_type (maxindex);
5291 TREE_TYPE (maxindex) = TYPE_DOMAIN (constructor_type);
5293 /* We shouldn't have an incomplete array type within
5295 if (constructor_stack->next)
5299 && tree_int_cst_lt (TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)),
5301 error_with_decl (constructor_decl, "zero-size array `%s'");
5302 layout_type (constructor_type);
5303 size = int_size_in_bytes (constructor_type);
5307 filled = size_binop (MULT_EXPR, constructor_unfilled_index,
5308 size_in_bytes (TREE_TYPE (constructor_type)));
5314 assemble_zeros (size - TREE_INT_CST_LOW (filled));
5316 resume_momentary (momentary);
5320 constructor_type = p->type;
5321 constructor_fields = p->fields;
5322 constructor_index = p->index;
5323 constructor_range_end = p->range_end;
5324 constructor_max_index = p->max_index;
5325 constructor_unfilled_index = p->unfilled_index;
5326 constructor_unfilled_fields = p->unfilled_fields;
5327 constructor_bit_index = p->bit_index;
5328 constructor_elements = p->elements;
5329 constructor_constant = p->constant;
5330 constructor_simple = p->simple;
5331 constructor_erroneous = p->erroneous;
5332 constructor_pending_elts = p->pending_elts;
5333 constructor_depth = p->depth;
5334 constructor_incremental = p->incremental;
5335 RESTORE_SPELLING_DEPTH (constructor_depth);
5337 constructor_stack = p->next;
5340 if (constructor == 0)
5342 if (constructor_stack == 0)
5343 return error_mark_node;
5349 /* Within an array initializer, specify the next index to be initialized.
5350 FIRST is that index. If LAST is nonzero, then initialize a range
5351 of indices, running from FIRST through LAST. */
5354 set_init_index (first, last)
5357 while ((TREE_CODE (first) == NOP_EXPR
5358 || TREE_CODE (first) == CONVERT_EXPR
5359 || TREE_CODE (first) == NON_LVALUE_EXPR)
5360 && (TYPE_MODE (TREE_TYPE (first))
5361 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0)))))
5362 (first) = TREE_OPERAND (first, 0);
5364 while ((TREE_CODE (last) == NOP_EXPR
5365 || TREE_CODE (last) == CONVERT_EXPR
5366 || TREE_CODE (last) == NON_LVALUE_EXPR)
5367 && (TYPE_MODE (TREE_TYPE (last))
5368 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0)))))
5369 (last) = TREE_OPERAND (last, 0);
5371 if (TREE_CODE (first) != INTEGER_CST)
5372 error_init ("nonconstant array index in initializer%s", " for `%s'", NULL);
5373 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5374 error_init ("nonconstant array index in initializer%s", " for `%s'", NULL);
5375 else if (tree_int_cst_lt (first, constructor_unfilled_index))
5376 error_init ("duplicate array index in initializer%s", " for `%s'", NULL);
5379 TREE_INT_CST_LOW (constructor_index)
5380 = TREE_INT_CST_LOW (first);
5381 TREE_INT_CST_HIGH (constructor_index)
5382 = TREE_INT_CST_HIGH (first);
5384 if (last != 0 && tree_int_cst_lt (last, first))
5385 error_init ("empty index range in initializer%s", " for `%s'", NULL);
5389 pedwarn ("ANSI C forbids specifying element to initialize");
5390 constructor_range_end = last;
5395 /* Within a struct initializer, specify the next field to be initialized. */
5398 set_init_label (fieldname)
5404 for (tail = TYPE_FIELDS (constructor_type); tail;
5405 tail = TREE_CHAIN (tail))
5407 if (tail == constructor_unfilled_fields)
5409 if (DECL_NAME (tail) == fieldname)
5414 error ("unknown field `%s' specified in initializer",
5415 IDENTIFIER_POINTER (fieldname));
5417 error ("field `%s' already initialized",
5418 IDENTIFIER_POINTER (fieldname));
5421 constructor_fields = tail;
5423 pedwarn ("ANSI C forbids specifying structure member to initialize");
5427 /* "Output" the next constructor element.
5428 At top level, really output it to assembler code now.
5429 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5430 TYPE is the data type that the containing data type wants here.
5431 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5433 PENDING if non-nil means output pending elements that belong
5434 right after this element. (PENDING is normally 1;
5435 it is 0 while outputting pending elements, to avoid recursion.) */
5438 output_init_element (value, type, field, pending)
5439 tree value, type, field;
5444 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5445 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5446 && !(TREE_CODE (value) == STRING_CST
5447 && TREE_CODE (type) == ARRAY_TYPE
5448 && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE)
5449 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5450 TYPE_MAIN_VARIANT (type))))
5451 value = default_conversion (value);
5453 if (value == error_mark_node)
5454 constructor_erroneous = 1;
5455 else if (!TREE_CONSTANT (value))
5456 constructor_constant = 0;
5457 else if (initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
5458 constructor_simple = 0;
5460 if (require_constant_value && ! TREE_CONSTANT (value))
5462 error_init ("initializer element%s is not constant",
5464 value = error_mark_node;
5466 else if (require_constant_elements
5467 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
5469 error_init ("initializer element%s is not computable at load time",
5471 value = error_mark_node;
5474 /* If this element duplicates one on constructor_pending_elts,
5475 print a message and ignore it. Don't do this when we're
5476 processing elements taken off constructor_pending_elts,
5477 because we'd always get spurious errors. */
5480 if (TREE_CODE (constructor_type) == RECORD_TYPE
5481 || TREE_CODE (constructor_type) == UNION_TYPE)
5483 if (purpose_member (field, constructor_pending_elts))
5485 error_init ("duplicate initializer%s", " for `%s'", NULL);
5489 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5492 for (tail = constructor_pending_elts; tail;
5493 tail = TREE_CHAIN (tail))
5494 if (TREE_PURPOSE (tail) != 0
5495 && TREE_CODE (TREE_PURPOSE (tail)) == INTEGER_CST
5496 && tree_int_cst_equal (TREE_PURPOSE (tail), constructor_index))
5501 error_init ("duplicate initializer%s", " for `%s'", NULL);
5507 /* If this element doesn't come next in sequence,
5508 put it on constructor_pending_elts. */
5509 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5510 && !tree_int_cst_equal (field, constructor_unfilled_index))
5513 /* The copy_node is needed in case field is actually
5514 constructor_index, which is modified in place. */
5515 constructor_pending_elts
5516 = tree_cons (copy_node (field),
5517 digest_init (type, value, 0, 0),
5518 constructor_pending_elts);
5520 else if ((TREE_CODE (constructor_type) == RECORD_TYPE
5521 || TREE_CODE (constructor_type) == UNION_TYPE)
5522 && field != constructor_unfilled_fields)
5525 constructor_pending_elts
5527 digest_init (type, value, 0, 0),
5528 constructor_pending_elts);
5532 /* Otherwise, output this element either to
5533 constructor_elements or to the assembler file. */
5537 if (! constructor_incremental)
5539 if (field && TREE_CODE (field) == INTEGER_CST)
5540 field = copy_node (field);
5541 constructor_elements
5542 = tree_cons (field, digest_init (type, value, 0, 0),
5543 constructor_elements);
5547 /* Structure elements may require alignment.
5548 Do this, if necessary. */
5549 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5551 /* Advance to offset of this element. */
5552 if (! tree_int_cst_equal (constructor_bit_index,
5553 DECL_FIELD_BITPOS (constructor_fields)))
5555 int next = (TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field))
5557 int here = (TREE_INT_CST_LOW (constructor_bit_index)
5560 assemble_zeros (next - here);
5563 output_constant (digest_init (type, value, 0, 0),
5564 int_size_in_bytes (type));
5566 /* For a record or union,
5567 keep track of end position of last field. */
5568 if (TREE_CODE (constructor_type) == RECORD_TYPE
5569 || TREE_CODE (constructor_type) == UNION_TYPE)
5571 tree temp = size_binop (PLUS_EXPR,
5572 DECL_FIELD_BITPOS (constructor_fields),
5573 DECL_SIZE (constructor_fields));
5574 TREE_INT_CST_LOW (constructor_bit_index)
5575 = TREE_INT_CST_LOW (temp);
5576 TREE_INT_CST_HIGH (constructor_bit_index)
5577 = TREE_INT_CST_HIGH (temp);
5582 /* Advance the variable that indicates sequential elements output. */
5583 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5585 tree tem = size_binop (PLUS_EXPR, constructor_unfilled_index,
5587 TREE_INT_CST_LOW (constructor_unfilled_index)
5588 = TREE_INT_CST_LOW (tem);
5589 TREE_INT_CST_HIGH (constructor_unfilled_index)
5590 = TREE_INT_CST_HIGH (tem);
5592 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5593 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5594 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5595 constructor_unfilled_fields = 0;
5597 /* Now output any pending elements which have become next. */
5599 output_pending_init_elements (0);
5603 /* Output any pending elements which have become next.
5604 As we output elements, constructor_unfilled_{fields,index}
5605 advances, which may cause other elements to become next;
5606 if so, they too are output.
5608 If ALL is 0, we return when there are
5609 no more pending elements to output now.
5611 If ALL is 1, we output space as necessary so that
5612 we can output all the pending elements. */
5615 output_pending_init_elements (all)
5623 /* Look thru the whole pending list.
5624 If we find an element that should be output now,
5625 output it. Otherwise, set NEXT to the element
5626 that comes first among those still pending. */
5629 for (tail = constructor_pending_elts; tail;
5630 tail = TREE_CHAIN (tail))
5632 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5634 if (tree_int_cst_equal (TREE_PURPOSE (tail),
5635 constructor_unfilled_index))
5637 output_init_element (TREE_VALUE (tail), TREE_TYPE (constructor_type),
5638 constructor_unfilled_index, 0);
5641 else if (tree_int_cst_lt (TREE_PURPOSE (tail),
5642 constructor_unfilled_index))
5645 || tree_int_cst_lt (TREE_PURPOSE (tail),
5647 next = TREE_PURPOSE (tail);
5649 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5650 || TREE_CODE (constructor_type) == UNION_TYPE)
5652 if (TREE_PURPOSE (tail) == constructor_unfilled_fields)
5654 output_init_element (TREE_VALUE (tail),
5655 TREE_TYPE (constructor_unfilled_fields),
5656 constructor_unfilled_fields,
5660 else if (tree_int_cst_lt (DECL_FIELD_BITPOS (TREE_PURPOSE (tail)),
5661 DECL_FIELD_BITPOS (constructor_unfilled_fields)))
5664 || tree_int_cst_lt (DECL_FIELD_BITPOS (TREE_PURPOSE (tail)),
5665 DECL_FIELD_BITPOS (next)))
5666 next = TREE_PURPOSE (tail);
5670 /* Ordinarily return, but not if we want to output all
5671 and there are elements left. */
5672 if (! (all && next != 0))
5675 /* Generate space up to the position of NEXT. */
5676 if (constructor_incremental)
5681 if (TREE_CODE (constructor_type) == RECORD_TYPE
5682 || TREE_CODE (constructor_type) == UNION_TYPE)
5684 /* Find the last field written out. */
5685 for (tail = TYPE_FIELDS (constructor_type); tail;
5686 tail = TREE_CHAIN (tail))
5687 if (TREE_CHAIN (tail) == constructor_unfilled_fields)
5689 /* Find the offset of the end of that field. */
5690 filled = size_binop (CEIL_DIV_EXPR,
5691 size_binop (PLUS_EXPR,
5692 DECL_FIELD_BITPOS (tail),
5694 size_int (BITS_PER_UNIT));
5695 nextpos_tree = size_binop (CEIL_DIV_EXPR,
5696 DECL_FIELD_BITPOS (next),
5697 size_int (BITS_PER_UNIT));
5698 constructor_unfilled_fields = next;
5700 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5702 filled = size_binop (MULT_EXPR, constructor_unfilled_index,
5703 size_in_bytes (TREE_TYPE (constructor_type)));
5705 = size_binop (MULT_EXPR, next,
5706 size_in_bytes (TREE_TYPE (constructor_type)));
5707 TREE_INT_CST_LOW (constructor_unfilled_index)
5708 = TREE_INT_CST_LOW (next);
5709 TREE_INT_CST_HIGH (constructor_unfilled_index)
5710 = TREE_INT_CST_HIGH (next);
5717 int nextpos = TREE_INT_CST_LOW (nextpos_tree);
5719 assemble_zeros (nextpos - TREE_INT_CST_LOW (filled));
5724 /* If it's not incremental, just skip over the gap,
5725 so that after jumping to retry we will output the next
5726 successive element. */
5727 if (TREE_CODE (constructor_type) == RECORD_TYPE
5728 || TREE_CODE (constructor_type) == UNION_TYPE)
5729 constructor_unfilled_fields = next;
5730 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5732 TREE_INT_CST_LOW (constructor_unfilled_index)
5733 = TREE_INT_CST_LOW (next);
5734 TREE_INT_CST_HIGH (constructor_unfilled_index)
5735 = TREE_INT_CST_HIGH (next);
5742 /* Add one non-braced element to the current constructor level.
5743 This adjusts the current position within the constructor's type.
5744 This may also start or terminate implicit levels
5745 to handle a partly-braced initializer.
5747 Once this has found the correct level for the new element,
5748 it calls output_init_element.
5750 Note: if we are incrementally outputting this constructor,
5751 this function may be called with a null argument
5752 representing a sub-constructor that was already incrementally output.
5753 When that happens, we output nothing, but we do the bookkeeping
5754 to skip past that element of the current constructor. */
5757 process_init_element (value)
5760 tree orig_value = value;
5761 int string_flag = value != 0 && TREE_CODE (value) == STRING_CST;
5763 /* Handle superfluous braces around string cst as in
5764 char x[] = {"foo"}; */
5766 && TREE_CODE (constructor_type) == ARRAY_TYPE
5767 && TREE_CODE (TREE_TYPE (constructor_type)) == INTEGER_TYPE
5768 && integer_zerop (constructor_unfilled_index))
5770 constructor_stack->replacement_value = value;
5774 if (constructor_stack->replacement_value != 0)
5776 error_init ("excess elements in struct initializer%s",
5777 " after `%s'", NULL_PTR);
5781 /* Ignore elements of a brace group if it is entirely superfluous
5782 and has already been diagnosed. */
5783 if (constructor_type == 0)
5786 /* If we've exhausted any levels that didn't have braces,
5788 while (constructor_stack->implicit)
5790 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5791 || TREE_CODE (constructor_type) == UNION_TYPE)
5792 && constructor_fields == 0)
5793 process_init_element (pop_init_level (1));
5794 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5795 && tree_int_cst_lt (constructor_max_index, constructor_index))
5796 process_init_element (pop_init_level (1));
5803 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5806 enum tree_code fieldcode;
5808 if (constructor_fields == 0)
5810 pedwarn_init ("excess elements in struct initializer%s",
5811 " after `%s'", NULL_PTR);
5815 fieldtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_fields));
5816 fieldcode = TREE_CODE (fieldtype);
5818 /* Accept a string constant to initialize a subarray. */
5820 && fieldcode == ARRAY_TYPE
5821 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
5824 /* Otherwise, if we have come to a subaggregate,
5825 and we don't have an element of its type, push into it. */
5826 else if (value != 0 && !constructor_no_implicit
5827 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
5828 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
5829 || fieldcode == UNION_TYPE))
5831 push_init_level (1);
5837 push_member_name (constructor_fields);
5838 output_init_element (value, fieldtype, constructor_fields, 1);
5839 RESTORE_SPELLING_DEPTH (constructor_depth);
5842 /* Do the bookkeeping for an element that was
5843 directly output as a constructor. */
5845 /* For a record, keep track of end position of last field. */
5846 tree temp = size_binop (PLUS_EXPR,
5847 DECL_FIELD_BITPOS (constructor_fields),
5848 DECL_SIZE (constructor_fields));
5849 TREE_INT_CST_LOW (constructor_bit_index)
5850 = TREE_INT_CST_LOW (temp);
5851 TREE_INT_CST_HIGH (constructor_bit_index)
5852 = TREE_INT_CST_HIGH (temp);
5854 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
5857 constructor_fields = TREE_CHAIN (constructor_fields);
5860 if (TREE_CODE (constructor_type) == UNION_TYPE)
5863 enum tree_code fieldcode;
5865 if (constructor_fields == 0)
5867 pedwarn_init ("excess elements in union initializer%s",
5868 " after `%s'", NULL_PTR);
5872 fieldtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_fields));
5873 fieldcode = TREE_CODE (fieldtype);
5875 /* Accept a string constant to initialize a subarray. */
5877 && fieldcode == ARRAY_TYPE
5878 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
5881 /* Otherwise, if we have come to a subaggregate,
5882 and we don't have an element of its type, push into it. */
5883 else if (value != 0 && !constructor_no_implicit
5884 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
5885 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
5886 || fieldcode == UNION_TYPE))
5888 push_init_level (1);
5894 push_member_name (constructor_fields);
5895 output_init_element (value, fieldtype, constructor_fields, 1);
5896 RESTORE_SPELLING_DEPTH (constructor_depth);
5899 /* Do the bookkeeping for an element that was
5900 directly output as a constructor. */
5902 TREE_INT_CST_LOW (constructor_bit_index)
5903 = TREE_INT_CST_LOW (DECL_SIZE (constructor_fields));
5904 TREE_INT_CST_HIGH (constructor_bit_index)
5905 = TREE_INT_CST_HIGH (DECL_SIZE (constructor_fields));
5907 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
5910 constructor_fields = 0;
5913 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5915 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5916 enum tree_code eltcode = TREE_CODE (elttype);
5918 /* Accept a string constant to initialize a subarray. */
5920 && eltcode == ARRAY_TYPE
5921 && TREE_CODE (TREE_TYPE (elttype)) == INTEGER_TYPE
5924 /* Otherwise, if we have come to a subaggregate,
5925 and we don't have an element of its type, push into it. */
5926 else if (value != 0 && !constructor_no_implicit
5927 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != elttype
5928 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
5929 || eltcode == UNION_TYPE))
5931 push_init_level (1);
5935 if (constructor_max_index != 0
5936 && tree_int_cst_lt (constructor_max_index, constructor_index))
5938 pedwarn_init ("excess elements in array initializer%s",
5939 " after `%s'", NULL_PTR);
5943 /* Now output the actual element.
5944 Ordinarily, output once.
5945 If there is a range, repeat it till we advance past the range. */
5952 push_array_bounds (TREE_INT_CST_LOW (constructor_index));
5953 output_init_element (value, elttype, constructor_index, 1);
5954 RESTORE_SPELLING_DEPTH (constructor_depth);
5957 tem = size_binop (PLUS_EXPR, constructor_index,
5959 TREE_INT_CST_LOW (constructor_index)
5960 = TREE_INT_CST_LOW (tem);
5961 TREE_INT_CST_HIGH (constructor_index)
5962 = TREE_INT_CST_HIGH (tem);
5965 /* If we are doing the bookkeeping for an element that was
5966 directly output as a constructor,
5967 we must update constructor_unfilled_index. */
5969 TREE_INT_CST_LOW (constructor_unfilled_index)
5970 = TREE_INT_CST_LOW (constructor_index);
5971 TREE_INT_CST_HIGH (constructor_unfilled_index)
5972 = TREE_INT_CST_HIGH (constructor_index);
5975 while (! (constructor_range_end == 0
5976 || tree_int_cst_lt (constructor_range_end,
5977 constructor_index)));
5982 /* Handle the sole element allowed in a braced initializer
5983 for a scalar variable. */
5984 if (constructor_fields == 0)
5986 pedwarn_init ("excess elements in scalar initializer%s",
5987 " after `%s'", NULL_PTR);
5992 output_init_element (value, constructor_type, NULL_TREE, 1);
5993 constructor_fields = 0;
5997 /* If the (lexically) previous elments are not now saved,
5998 we can discard the storage for them. */
5999 if (constructor_incremental && constructor_pending_elts == 0 && value != 0)
6003 /* Expand an ASM statement with operands, handling output operands
6004 that are not variables or INDIRECT_REFS by transforming such
6005 cases into cases that expand_asm_operands can handle.
6007 Arguments are same as for expand_asm_operands. */
6010 c_expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line)
6011 tree string, outputs, inputs, clobbers;
6016 int noutputs = list_length (outputs);
6018 /* o[I] is the place that output number I should be written. */
6019 register tree *o = (tree *) alloca (noutputs * sizeof (tree));
6022 if (TREE_CODE (string) == ADDR_EXPR)
6023 string = TREE_OPERAND (string, 0);
6024 if (TREE_CODE (string) != STRING_CST)
6026 error ("asm template is not a string constant");
6030 /* Record the contents of OUTPUTS before it is modified. */
6031 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6032 o[i] = TREE_VALUE (tail);
6034 /* Perform default conversions on array and function inputs. */
6035 /* Don't do this for other types--
6036 it would screw up operands expected to be in memory. */
6037 for (i = 0, tail = inputs; tail; tail = TREE_CHAIN (tail), i++)
6038 if (TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == ARRAY_TYPE
6039 || TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == FUNCTION_TYPE)
6040 TREE_VALUE (tail) = default_conversion (TREE_VALUE (tail));
6042 /* Generate the ASM_OPERANDS insn;
6043 store into the TREE_VALUEs of OUTPUTS some trees for
6044 where the values were actually stored. */
6045 expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line);
6047 /* Copy all the intermediate outputs into the specified outputs. */
6048 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6050 if (o[i] != TREE_VALUE (tail))
6052 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
6056 /* Detect modification of read-only values.
6057 (Otherwise done by build_modify_expr.) */
6060 tree type = TREE_TYPE (o[i]);
6061 if (TYPE_READONLY (type)
6062 || ((TREE_CODE (type) == RECORD_TYPE
6063 || TREE_CODE (type) == UNION_TYPE)
6064 && C_TYPE_FIELDS_READONLY (type)))
6065 readonly_warning (o[i], "modification by `asm'");
6069 /* Those MODIFY_EXPRs could do autoincrements. */
6073 /* Expand a C `return' statement.
6074 RETVAL is the expression for what to return,
6075 or a null pointer for `return;' with no value. */
6078 c_expand_return (retval)
6081 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6083 if (TREE_THIS_VOLATILE (current_function_decl))
6084 warning ("function declared `volatile' has a `return' statement");
6088 current_function_returns_null = 1;
6089 if (warn_return_type && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6090 warning ("`return' with no value, in function returning non-void");
6091 expand_null_return ();
6093 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6095 current_function_returns_null = 1;
6096 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6097 pedwarn ("`return' with a value, in function returning void");
6098 expand_return (retval);
6102 tree t = convert_for_assignment (valtype, retval, "return",
6103 NULL_TREE, NULL_TREE, 0);
6104 tree res = DECL_RESULT (current_function_decl);
6105 t = build (MODIFY_EXPR, TREE_TYPE (res),
6106 res, convert (TREE_TYPE (res), t));
6107 TREE_SIDE_EFFECTS (t) = 1;
6109 current_function_returns_value = 1;
6113 /* Start a C switch statement, testing expression EXP.
6114 Return EXP if it is valid, an error node otherwise. */
6117 c_expand_start_case (exp)
6120 register enum tree_code code = TREE_CODE (TREE_TYPE (exp));
6121 tree type = TREE_TYPE (exp);
6123 if (code != INTEGER_TYPE && code != ENUMERAL_TYPE && code != ERROR_MARK)
6125 error ("switch quantity not an integer");
6126 exp = error_mark_node;
6131 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6133 if (warn_traditional
6134 && (type == long_integer_type_node
6135 || type == long_unsigned_type_node))
6136 pedwarn ("`long' switch expression not converted to `int' in ANSI C");
6138 exp = default_conversion (exp);
6139 type = TREE_TYPE (exp);
6140 index = get_unwidened (exp, NULL_TREE);
6141 /* We can't strip a conversion from a signed type to an unsigned,
6142 because if we did, int_fits_type_p would do the wrong thing
6143 when checking case values for being in range,
6144 and it's too hard to do the right thing. */
6145 if (TREE_UNSIGNED (TREE_TYPE (exp))
6146 == TREE_UNSIGNED (TREE_TYPE (index)))
6150 expand_start_case (1, exp, type, "switch statement");