1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 88, 91, 92-5, 1996 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* This file is part of the C front end.
23 It contains routines to build C expressions given their operands,
24 including computing the types of the result, C-specific error checks,
25 and some optimization.
27 There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
28 and to process initializations in declarations (since they work
29 like a strange sort of assignment). */
38 /* Nonzero if we've already printed a "missing braces around initializer"
39 message within this initializer. */
40 static int missing_braces_mentioned;
42 extern char *index ();
43 extern char *rindex ();
45 static tree qualify_type PROTO((tree, tree));
46 static int comp_target_types PROTO((tree, tree));
47 static int function_types_compatible_p PROTO((tree, tree));
48 static int type_lists_compatible_p PROTO((tree, tree));
49 static int self_promoting_type_p PROTO((tree));
50 static tree decl_constant_value PROTO((tree));
51 static tree lookup_field PROTO((tree, tree, tree *));
52 static tree convert_arguments PROTO((tree, tree, tree, tree));
53 static tree pointer_int_sum PROTO((enum tree_code, tree, tree));
54 static tree pointer_diff PROTO((tree, tree));
55 static tree unary_complex_lvalue PROTO((enum tree_code, tree));
56 static void pedantic_lvalue_warning PROTO((enum tree_code));
57 static tree internal_build_compound_expr PROTO((tree, int));
58 static tree convert_for_assignment PROTO((tree, tree, char *, tree,
60 static void warn_for_assignment PROTO((char *, char *, tree, int));
61 static tree valid_compound_expr_initializer PROTO((tree, tree));
62 static void push_string PROTO((char *));
63 static void push_member_name PROTO((tree));
64 static void push_array_bounds PROTO((int));
65 static int spelling_length PROTO((void));
66 static char *print_spelling PROTO((char *));
67 static char *get_spelling PROTO((char *));
68 static void warning_init PROTO((char *, char *,
70 static tree digest_init PROTO((tree, tree, int, int));
71 static void check_init_type_bitfields PROTO((tree));
72 static void output_init_element PROTO((tree, tree, tree, int));
73 static void output_pending_init_elements PROTO((int));
75 /* Do `exp = require_complete_type (exp);' to make sure exp
76 does not have an incomplete type. (That includes void types.) */
79 require_complete_type (value)
82 tree type = TREE_TYPE (value);
84 /* First, detect a valid value with a complete type. */
85 if (TYPE_SIZE (type) != 0
86 && type != void_type_node)
89 incomplete_type_error (value, type);
90 return error_mark_node;
93 /* Print an error message for invalid use of an incomplete type.
94 VALUE is the expression that was used (or 0 if that isn't known)
95 and TYPE is the type that was invalid. */
98 incomplete_type_error (value, type)
104 /* Avoid duplicate error message. */
105 if (TREE_CODE (type) == ERROR_MARK)
108 if (value != 0 && (TREE_CODE (value) == VAR_DECL
109 || TREE_CODE (value) == PARM_DECL))
110 error ("`%s' has an incomplete type",
111 IDENTIFIER_POINTER (DECL_NAME (value)));
115 /* We must print an error message. Be clever about what it says. */
117 switch (TREE_CODE (type))
120 errmsg = "invalid use of undefined type `struct %s'";
124 errmsg = "invalid use of undefined type `union %s'";
128 errmsg = "invalid use of undefined type `enum %s'";
132 error ("invalid use of void expression");
136 if (TYPE_DOMAIN (type))
138 type = TREE_TYPE (type);
141 error ("invalid use of array with unspecified bounds");
148 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
149 error (errmsg, IDENTIFIER_POINTER (TYPE_NAME (type)));
151 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
152 error ("invalid use of incomplete typedef `%s'",
153 IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
157 /* Return a variant of TYPE which has all the type qualifiers of LIKE
158 as well as those of TYPE. */
161 qualify_type (type, like)
164 int constflag = TYPE_READONLY (type) || TYPE_READONLY (like);
165 int volflag = TYPE_VOLATILE (type) || TYPE_VOLATILE (like);
166 return c_build_type_variant (type, constflag, volflag);
169 /* Return the common type of two types.
170 We assume that comptypes has already been done and returned 1;
171 if that isn't so, this may crash. In particular, we assume that qualifiers
174 This is the type for the result of most arithmetic operations
175 if the operands have the given two types. */
181 register enum tree_code code1;
182 register enum tree_code code2;
185 /* Save time if the two types are the same. */
187 if (t1 == t2) return t1;
189 /* If one type is nonsense, use the other. */
190 if (t1 == error_mark_node)
192 if (t2 == error_mark_node)
195 /* Merge the attributes */
196 attributes = merge_attributes (TYPE_ATTRIBUTES (t1), TYPE_ATTRIBUTES (t2));
198 /* Treat an enum type as the unsigned integer type of the same width. */
200 if (TREE_CODE (t1) == ENUMERAL_TYPE)
201 t1 = type_for_size (TYPE_PRECISION (t1), 1);
202 if (TREE_CODE (t2) == ENUMERAL_TYPE)
203 t2 = type_for_size (TYPE_PRECISION (t2), 1);
205 code1 = TREE_CODE (t1);
206 code2 = TREE_CODE (t2);
208 /* If one type is complex, form the common type of the non-complex
209 components, then make that complex. Use T1 or T2 if it is the
211 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
213 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
214 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
215 tree subtype = common_type (subtype1, subtype2);
217 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
218 return build_type_attribute_variant (t1, attributes);
219 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
220 return build_type_attribute_variant (t2, attributes);
222 return build_type_attribute_variant (build_complex_type (subtype),
230 /* If only one is real, use it as the result. */
232 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
233 return build_type_attribute_variant (t1, attributes);
235 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
236 return build_type_attribute_variant (t2, attributes);
238 /* Both real or both integers; use the one with greater precision. */
240 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
241 return build_type_attribute_variant (t1, attributes);
242 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
243 return build_type_attribute_variant (t2, attributes);
245 /* Same precision. Prefer longs to ints even when same size. */
247 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
248 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
249 return build_type_attribute_variant (long_unsigned_type_node,
252 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
253 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
255 /* But preserve unsignedness from the other type,
256 since long cannot hold all the values of an unsigned int. */
257 if (TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
258 t1 = long_unsigned_type_node;
260 t1 = long_integer_type_node;
261 return build_type_attribute_variant (t1, attributes);
264 /* Otherwise prefer the unsigned one. */
266 if (TREE_UNSIGNED (t1))
267 return build_type_attribute_variant (t1, attributes);
269 return build_type_attribute_variant (t2, attributes);
272 /* For two pointers, do this recursively on the target type,
273 and combine the qualifiers of the two types' targets. */
274 /* This code was turned off; I don't know why.
275 But ANSI C specifies doing this with the qualifiers.
276 So I turned it on again. */
278 tree target = common_type (TYPE_MAIN_VARIANT (TREE_TYPE (t1)),
279 TYPE_MAIN_VARIANT (TREE_TYPE (t2)));
281 = TYPE_READONLY (TREE_TYPE (t1)) || TYPE_READONLY (TREE_TYPE (t2));
283 = TYPE_VOLATILE (TREE_TYPE (t1)) || TYPE_VOLATILE (TREE_TYPE (t2));
284 t1 = build_pointer_type (c_build_type_variant (target, constp,
286 return build_type_attribute_variant (t1, attributes);
289 t1 = build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2)));
290 return build_type_attribute_variant (t1, attributes);
295 tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
296 /* Save space: see if the result is identical to one of the args. */
297 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
298 return build_type_attribute_variant (t1, attributes);
299 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
300 return build_type_attribute_variant (t2, attributes);
301 /* Merge the element types, and have a size if either arg has one. */
302 t1 = build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
303 return build_type_attribute_variant (t1, attributes);
307 /* Function types: prefer the one that specified arg types.
308 If both do, merge the arg types. Also merge the return types. */
310 tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
311 tree p1 = TYPE_ARG_TYPES (t1);
312 tree p2 = TYPE_ARG_TYPES (t2);
317 /* Save space: see if the result is identical to one of the args. */
318 if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2))
319 return build_type_attribute_variant (t1, attributes);
320 if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1))
321 return build_type_attribute_variant (t2, attributes);
323 /* Simple way if one arg fails to specify argument types. */
324 if (TYPE_ARG_TYPES (t1) == 0)
326 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
327 return build_type_attribute_variant (t1, attributes);
329 if (TYPE_ARG_TYPES (t2) == 0)
331 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
332 return build_type_attribute_variant (t1, attributes);
335 /* If both args specify argument types, we must merge the two
336 lists, argument by argument. */
338 len = list_length (p1);
341 for (i = 0; i < len; i++)
342 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
347 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
349 /* A null type means arg type is not specified.
350 Take whatever the other function type has. */
351 if (TREE_VALUE (p1) == 0)
353 TREE_VALUE (n) = TREE_VALUE (p2);
356 if (TREE_VALUE (p2) == 0)
358 TREE_VALUE (n) = TREE_VALUE (p1);
362 /* Given wait (union {union wait *u; int *i} *)
363 and wait (union wait *),
364 prefer union wait * as type of parm. */
365 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
366 && TREE_VALUE (p1) != TREE_VALUE (p2))
369 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
370 memb; memb = TREE_CHAIN (memb))
371 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2)))
373 TREE_VALUE (n) = TREE_VALUE (p2);
375 pedwarn ("function types not truly compatible in ANSI C");
379 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
380 && TREE_VALUE (p2) != TREE_VALUE (p1))
383 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
384 memb; memb = TREE_CHAIN (memb))
385 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1)))
387 TREE_VALUE (n) = TREE_VALUE (p1);
389 pedwarn ("function types not truly compatible in ANSI C");
393 TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2));
397 t1 = build_function_type (valtype, newargs);
398 /* ... falls through ... */
402 return build_type_attribute_variant (t1, attributes);
407 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
408 or various other operations. Return 2 if they are compatible
409 but a warning may be needed if you use them together. */
412 comptypes (type1, type2)
415 register tree t1 = type1;
416 register tree t2 = type2;
419 /* Suppress errors caused by previously reported errors. */
421 if (t1 == t2 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
424 /* Treat an enum type as the integer type of the same width and
427 if (TREE_CODE (t1) == ENUMERAL_TYPE)
428 t1 = type_for_size (TYPE_PRECISION (t1), TREE_UNSIGNED (t1));
429 if (TREE_CODE (t2) == ENUMERAL_TYPE)
430 t2 = type_for_size (TYPE_PRECISION (t2), TREE_UNSIGNED (t2));
435 /* Different classes of types can't be compatible. */
437 if (TREE_CODE (t1) != TREE_CODE (t2)) return 0;
439 /* Qualifiers must match. */
441 if (TYPE_READONLY (t1) != TYPE_READONLY (t2))
443 if (TYPE_VOLATILE (t1) != TYPE_VOLATILE (t2))
446 /* Allow for two different type nodes which have essentially the same
447 definition. Note that we already checked for equality of the type
448 type qualifiers (just above). */
450 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
453 #ifndef COMP_TYPE_ATTRIBUTES
454 #define COMP_TYPE_ATTRIBUTES(t1,t2) 1
457 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
458 if (! (attrval = COMP_TYPE_ATTRIBUTES (t1, t2)))
461 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
464 switch (TREE_CODE (t1))
467 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
468 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
472 val = function_types_compatible_p (t1, t2);
477 tree d1 = TYPE_DOMAIN (t1);
478 tree d2 = TYPE_DOMAIN (t2);
481 /* Target types must match incl. qualifiers. */
482 if (TREE_TYPE (t1) != TREE_TYPE (t2)
483 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
486 /* Sizes must match unless one is missing or variable. */
487 if (d1 == 0 || d2 == 0 || d1 == d2
488 || TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
489 || TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
490 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST
491 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)
494 if (! ((TREE_INT_CST_LOW (TYPE_MIN_VALUE (d1))
495 == TREE_INT_CST_LOW (TYPE_MIN_VALUE (d2)))
496 && (TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d1))
497 == TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d2)))
498 && (TREE_INT_CST_LOW (TYPE_MAX_VALUE (d1))
499 == TREE_INT_CST_LOW (TYPE_MAX_VALUE (d2)))
500 && (TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d1))
501 == TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d2)))))
507 if (maybe_objc_comptypes (t1, t2, 0) == 1)
511 return attrval == 2 && val == 1 ? 2 : val;
514 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
515 ignoring their qualifiers. */
518 comp_target_types (ttl, ttr)
523 /* Give maybe_objc_comptypes a crack at letting these types through. */
524 if (val = maybe_objc_comptypes (ttl, ttr, 1) >= 0)
527 val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)),
528 TYPE_MAIN_VARIANT (TREE_TYPE (ttr)));
530 if (val == 2 && pedantic)
531 pedwarn ("types are not quite compatible");
535 /* Subroutines of `comptypes'. */
537 /* Return 1 if two function types F1 and F2 are compatible.
538 If either type specifies no argument types,
539 the other must specify a fixed number of self-promoting arg types.
540 Otherwise, if one type specifies only the number of arguments,
541 the other must specify that number of self-promoting arg types.
542 Otherwise, the argument types must match. */
545 function_types_compatible_p (f1, f2)
549 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
553 if (!(TREE_TYPE (f1) == TREE_TYPE (f2)
554 || (val = comptypes (TREE_TYPE (f1), TREE_TYPE (f2)))))
557 args1 = TYPE_ARG_TYPES (f1);
558 args2 = TYPE_ARG_TYPES (f2);
560 /* An unspecified parmlist matches any specified parmlist
561 whose argument types don't need default promotions. */
565 if (!self_promoting_args_p (args2))
567 /* If one of these types comes from a non-prototype fn definition,
568 compare that with the other type's arglist.
569 If they don't match, ask for a warning (but no error). */
570 if (TYPE_ACTUAL_ARG_TYPES (f1)
571 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
577 if (!self_promoting_args_p (args1))
579 if (TYPE_ACTUAL_ARG_TYPES (f2)
580 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
585 /* Both types have argument lists: compare them and propagate results. */
586 val1 = type_lists_compatible_p (args1, args2);
587 return val1 != 1 ? val1 : val;
590 /* Check two lists of types for compatibility,
591 returning 0 for incompatible, 1 for compatible,
592 or 2 for compatible with warning. */
595 type_lists_compatible_p (args1, args2)
598 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
604 if (args1 == 0 && args2 == 0)
606 /* If one list is shorter than the other,
607 they fail to match. */
608 if (args1 == 0 || args2 == 0)
610 /* A null pointer instead of a type
611 means there is supposed to be an argument
612 but nothing is specified about what type it has.
613 So match anything that self-promotes. */
614 if (TREE_VALUE (args1) == 0)
616 if (! self_promoting_type_p (TREE_VALUE (args2)))
619 else if (TREE_VALUE (args2) == 0)
621 if (! self_promoting_type_p (TREE_VALUE (args1)))
624 else if (! (newval = comptypes (TREE_VALUE (args1), TREE_VALUE (args2))))
626 /* Allow wait (union {union wait *u; int *i} *)
627 and wait (union wait *) to be compatible. */
628 if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE
629 && (TYPE_NAME (TREE_VALUE (args1)) == 0
630 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args1)))
631 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST
632 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)),
633 TYPE_SIZE (TREE_VALUE (args2))))
636 for (memb = TYPE_FIELDS (TREE_VALUE (args1));
637 memb; memb = TREE_CHAIN (memb))
638 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2)))
643 else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE
644 && (TYPE_NAME (TREE_VALUE (args2)) == 0
645 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args2)))
646 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST
647 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)),
648 TYPE_SIZE (TREE_VALUE (args1))))
651 for (memb = TYPE_FIELDS (TREE_VALUE (args2));
652 memb; memb = TREE_CHAIN (memb))
653 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1)))
662 /* comptypes said ok, but record if it said to warn. */
666 args1 = TREE_CHAIN (args1);
667 args2 = TREE_CHAIN (args2);
671 /* Return 1 if PARMS specifies a fixed number of parameters
672 and none of their types is affected by default promotions. */
675 self_promoting_args_p (parms)
679 for (t = parms; t; t = TREE_CHAIN (t))
681 register tree type = TREE_VALUE (t);
683 if (TREE_CHAIN (t) == 0 && type != void_type_node)
689 if (TYPE_MAIN_VARIANT (type) == float_type_node)
692 if (C_PROMOTING_INTEGER_TYPE_P (type))
698 /* Return 1 if TYPE is not affected by default promotions. */
701 self_promoting_type_p (type)
704 if (TYPE_MAIN_VARIANT (type) == float_type_node)
707 if (C_PROMOTING_INTEGER_TYPE_P (type))
713 /* Return an unsigned type the same as TYPE in other respects. */
719 tree type1 = TYPE_MAIN_VARIANT (type);
720 if (type1 == signed_char_type_node || type1 == char_type_node)
721 return unsigned_char_type_node;
722 if (type1 == integer_type_node)
723 return unsigned_type_node;
724 if (type1 == short_integer_type_node)
725 return short_unsigned_type_node;
726 if (type1 == long_integer_type_node)
727 return long_unsigned_type_node;
728 if (type1 == long_long_integer_type_node)
729 return long_long_unsigned_type_node;
730 if (type1 == intDI_type_node)
731 return unsigned_intDI_type_node;
732 if (type1 == intSI_type_node)
733 return unsigned_intSI_type_node;
734 if (type1 == intHI_type_node)
735 return unsigned_intHI_type_node;
736 if (type1 == intQI_type_node)
737 return unsigned_intQI_type_node;
739 return signed_or_unsigned_type (1, type);
742 /* Return a signed type the same as TYPE in other respects. */
748 tree type1 = TYPE_MAIN_VARIANT (type);
749 if (type1 == unsigned_char_type_node || type1 == char_type_node)
750 return signed_char_type_node;
751 if (type1 == unsigned_type_node)
752 return integer_type_node;
753 if (type1 == short_unsigned_type_node)
754 return short_integer_type_node;
755 if (type1 == long_unsigned_type_node)
756 return long_integer_type_node;
757 if (type1 == long_long_unsigned_type_node)
758 return long_long_integer_type_node;
759 if (type1 == unsigned_intDI_type_node)
760 return intDI_type_node;
761 if (type1 == unsigned_intSI_type_node)
762 return intSI_type_node;
763 if (type1 == unsigned_intHI_type_node)
764 return intHI_type_node;
765 if (type1 == unsigned_intQI_type_node)
766 return intQI_type_node;
768 return signed_or_unsigned_type (0, type);
771 /* Return a type the same as TYPE except unsigned or
772 signed according to UNSIGNEDP. */
775 signed_or_unsigned_type (unsignedp, type)
779 if (! INTEGRAL_TYPE_P (type))
781 if (TYPE_PRECISION (type) == TYPE_PRECISION (signed_char_type_node))
782 return unsignedp ? unsigned_char_type_node : signed_char_type_node;
783 if (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
784 return unsignedp ? unsigned_type_node : integer_type_node;
785 if (TYPE_PRECISION (type) == TYPE_PRECISION (short_integer_type_node))
786 return unsignedp ? short_unsigned_type_node : short_integer_type_node;
787 if (TYPE_PRECISION (type) == TYPE_PRECISION (long_integer_type_node))
788 return unsignedp ? long_unsigned_type_node : long_integer_type_node;
789 if (TYPE_PRECISION (type) == TYPE_PRECISION (long_long_integer_type_node))
790 return (unsignedp ? long_long_unsigned_type_node
791 : long_long_integer_type_node);
795 /* Compute the value of the `sizeof' operator. */
801 enum tree_code code = TREE_CODE (type);
804 if (code == FUNCTION_TYPE)
806 if (pedantic || warn_pointer_arith)
807 pedwarn ("sizeof applied to a function type");
810 if (code == VOID_TYPE)
812 if (pedantic || warn_pointer_arith)
813 pedwarn ("sizeof applied to a void type");
816 if (code == ERROR_MARK)
818 if (TYPE_SIZE (type) == 0)
820 error ("sizeof applied to an incomplete type");
824 /* Convert in case a char is more than one unit. */
825 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
826 size_int (TYPE_PRECISION (char_type_node)));
827 /* size_binop does not put the constant in range, so do it now. */
828 if (TREE_CODE (t) == INTEGER_CST && force_fit_type (t, 0))
829 TREE_CONSTANT_OVERFLOW (t) = TREE_OVERFLOW (t) = 1;
834 c_sizeof_nowarn (type)
837 enum tree_code code = TREE_CODE (type);
840 if (code == FUNCTION_TYPE
842 || code == ERROR_MARK)
844 if (TYPE_SIZE (type) == 0)
847 /* Convert in case a char is more than one unit. */
848 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
849 size_int (TYPE_PRECISION (char_type_node)));
850 force_fit_type (t, 0);
854 /* Compute the size to increment a pointer by. */
857 c_size_in_bytes (type)
860 enum tree_code code = TREE_CODE (type);
863 if (code == FUNCTION_TYPE)
865 if (code == VOID_TYPE)
867 if (code == ERROR_MARK)
869 if (TYPE_SIZE (type) == 0)
871 error ("arithmetic on pointer to an incomplete type");
875 /* Convert in case a char is more than one unit. */
876 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
877 size_int (BITS_PER_UNIT));
878 force_fit_type (t, 0);
882 /* Implement the __alignof keyword: Return the minimum required
883 alignment of TYPE, measured in bytes. */
889 enum tree_code code = TREE_CODE (type);
891 if (code == FUNCTION_TYPE)
892 return size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
894 if (code == VOID_TYPE || code == ERROR_MARK)
897 return size_int (TYPE_ALIGN (type) / BITS_PER_UNIT);
900 /* Implement the __alignof keyword: Return the minimum required
901 alignment of EXPR, measured in bytes. For VAR_DECL's and
902 FIELD_DECL's return DECL_ALIGN (which can be set from an
903 "aligned" __attribute__ specification). */
906 c_alignof_expr (expr)
909 if (TREE_CODE (expr) == VAR_DECL)
910 return size_int (DECL_ALIGN (expr) / BITS_PER_UNIT);
912 if (TREE_CODE (expr) == COMPONENT_REF
913 && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1)))
915 error ("`__alignof' applied to a bit-field");
918 else if (TREE_CODE (expr) == COMPONENT_REF
919 && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
920 return size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT);
922 if (TREE_CODE (expr) == INDIRECT_REF)
924 tree t = TREE_OPERAND (expr, 0);
926 int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
928 while (TREE_CODE (t) == NOP_EXPR
929 && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
933 t = TREE_OPERAND (t, 0);
934 thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
935 if (thisalign > bestalign)
936 best = t, bestalign = thisalign;
938 return c_alignof (TREE_TYPE (TREE_TYPE (best)));
941 return c_alignof (TREE_TYPE (expr));
944 /* Return either DECL or its known constant value (if it has one). */
947 decl_constant_value (decl)
950 if (/* Don't change a variable array bound or initial value to a constant
951 in a place where a variable is invalid. */
952 current_function_decl != 0
954 && ! TREE_THIS_VOLATILE (decl)
955 && TREE_READONLY (decl) && ! ITERATOR_P (decl)
956 && DECL_INITIAL (decl) != 0
957 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
958 /* This is invalid if initial value is not constant.
959 If it has either a function call, a memory reference,
960 or a variable, then re-evaluating it could give different results. */
961 && TREE_CONSTANT (DECL_INITIAL (decl))
962 /* Check for cases where this is sub-optimal, even though valid. */
963 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR
964 && DECL_MODE (decl) != BLKmode)
965 return DECL_INITIAL (decl);
969 /* Perform default promotions for C data used in expressions.
970 Arrays and functions are converted to pointers;
971 enumeral types or short or char, to int.
972 In addition, manifest constants symbols are replaced by their values. */
975 default_conversion (exp)
978 register tree type = TREE_TYPE (exp);
979 register enum tree_code code = TREE_CODE (type);
981 /* Constants can be used directly unless they're not loadable. */
982 if (TREE_CODE (exp) == CONST_DECL)
983 exp = DECL_INITIAL (exp);
985 /* Replace a nonvolatile const static variable with its value unless
986 it is an array, in which case we must be sure that taking the
987 address of the array produces consistent results. */
988 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
990 exp = decl_constant_value (exp);
991 type = TREE_TYPE (exp);
994 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
996 /* Do not use STRIP_NOPS here! It will remove conversions from pointer
997 to integer and cause infinite recursion. */
998 while (TREE_CODE (exp) == NON_LVALUE_EXPR
999 || (TREE_CODE (exp) == NOP_EXPR
1000 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
1001 exp = TREE_OPERAND (exp, 0);
1003 /* Normally convert enums to int,
1004 but convert wide enums to something wider. */
1005 if (code == ENUMERAL_TYPE)
1007 type = type_for_size (MAX (TYPE_PRECISION (type),
1008 TYPE_PRECISION (integer_type_node)),
1010 || TYPE_PRECISION (type) >= TYPE_PRECISION (integer_type_node))
1011 && TREE_UNSIGNED (type)));
1012 return convert (type, exp);
1015 if (TREE_CODE (exp) == COMPONENT_REF
1016 && DECL_BIT_FIELD (TREE_OPERAND (exp, 1)))
1018 tree width = DECL_SIZE (TREE_OPERAND (exp, 1));
1019 HOST_WIDE_INT low = TREE_INT_CST_LOW (width);
1021 /* If it's thinner than an int, promote it like a
1022 C_PROMOTING_INTEGER_TYPE_P, otherwise leave it alone. */
1024 if (low < TYPE_PRECISION (integer_type_node))
1026 if ( flag_traditional && TREE_UNSIGNED (type))
1027 return convert (unsigned_type_node, exp);
1029 return convert (integer_type_node, exp);
1033 if (C_PROMOTING_INTEGER_TYPE_P (type))
1035 /* Traditionally, unsignedness is preserved in default promotions.
1036 Also preserve unsignedness if not really getting any wider. */
1037 if (TREE_UNSIGNED (type)
1038 && (flag_traditional
1039 || TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
1040 return convert (unsigned_type_node, exp);
1041 return convert (integer_type_node, exp);
1043 if (flag_traditional && !flag_allow_single_precision
1044 && TYPE_MAIN_VARIANT (type) == float_type_node)
1045 return convert (double_type_node, exp);
1046 if (code == VOID_TYPE)
1048 error ("void value not ignored as it ought to be");
1049 return error_mark_node;
1051 if (code == FUNCTION_TYPE)
1053 return build_unary_op (ADDR_EXPR, exp, 0);
1055 if (code == ARRAY_TYPE)
1058 tree restype = TREE_TYPE (type);
1063 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r'
1064 || TREE_CODE_CLASS (TREE_CODE (exp)) == 'd')
1066 constp = TREE_READONLY (exp);
1067 volatilep = TREE_THIS_VOLATILE (exp);
1070 if (TYPE_READONLY (type) || TYPE_VOLATILE (type)
1071 || constp || volatilep)
1072 restype = c_build_type_variant (restype,
1073 TYPE_READONLY (type) || constp,
1074 TYPE_VOLATILE (type) || volatilep);
1076 if (TREE_CODE (exp) == INDIRECT_REF)
1077 return convert (TYPE_POINTER_TO (restype),
1078 TREE_OPERAND (exp, 0));
1080 if (TREE_CODE (exp) == COMPOUND_EXPR)
1082 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
1083 return build (COMPOUND_EXPR, TREE_TYPE (op1),
1084 TREE_OPERAND (exp, 0), op1);
1088 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1090 error ("invalid use of non-lvalue array");
1091 return error_mark_node;
1094 ptrtype = build_pointer_type (restype);
1096 if (TREE_CODE (exp) == VAR_DECL)
1098 /* ??? This is not really quite correct
1099 in that the type of the operand of ADDR_EXPR
1100 is not the target type of the type of the ADDR_EXPR itself.
1101 Question is, can this lossage be avoided? */
1102 adr = build1 (ADDR_EXPR, ptrtype, exp);
1103 if (mark_addressable (exp) == 0)
1104 return error_mark_node;
1105 TREE_CONSTANT (adr) = staticp (exp);
1106 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1109 /* This way is better for a COMPONENT_REF since it can
1110 simplify the offset for a component. */
1111 adr = build_unary_op (ADDR_EXPR, exp, 1);
1112 return convert (ptrtype, adr);
1117 /* Look up component name in the structure type definition.
1119 If this component name is found indirectly within an anonymous union,
1120 store in *INDIRECT the component which directly contains
1121 that anonymous union. Otherwise, set *INDIRECT to 0. */
1124 lookup_field (type, component, indirect)
1125 tree type, component;
1130 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1131 to the field elements. Use a binary search on this array to quickly
1132 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1133 will always be set for structures which have many elements. */
1135 if (TYPE_LANG_SPECIFIC (type))
1138 tree *field_array = &TYPE_LANG_SPECIFIC (type)->elts[0];
1140 field = TYPE_FIELDS (type);
1142 top = TYPE_LANG_SPECIFIC (type)->len;
1143 while (top - bot > 1)
1145 half = (top - bot + 1) >> 1;
1146 field = field_array[bot+half];
1148 if (DECL_NAME (field) == NULL_TREE)
1150 /* Step through all anon unions in linear fashion. */
1151 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1155 field = field_array[bot++];
1156 anon = lookup_field (TREE_TYPE (field), component, &junk);
1157 if (anon != NULL_TREE)
1164 /* Entire record is only anon unions. */
1168 /* Restart the binary search, with new lower bound. */
1172 if (DECL_NAME (field) == component)
1174 if (DECL_NAME (field) < component)
1180 if (DECL_NAME (field_array[bot]) == component)
1181 field = field_array[bot];
1182 else if (DECL_NAME (field) != component)
1187 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1189 if (DECL_NAME (field) == NULL_TREE)
1192 tree anon = lookup_field (TREE_TYPE (field), component, &junk);
1193 if (anon != NULL_TREE)
1200 if (DECL_NAME (field) == component)
1205 *indirect = NULL_TREE;
1209 /* Make an expression to refer to the COMPONENT field of
1210 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1213 build_component_ref (datum, component)
1214 tree datum, component;
1216 register tree type = TREE_TYPE (datum);
1217 register enum tree_code code = TREE_CODE (type);
1218 register tree field = NULL;
1221 /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it
1222 unless we are not to support things not strictly ANSI. */
1223 switch (TREE_CODE (datum))
1227 tree value = build_component_ref (TREE_OPERAND (datum, 1), component);
1228 return build (COMPOUND_EXPR, TREE_TYPE (value),
1229 TREE_OPERAND (datum, 0), value);
1232 return build_conditional_expr
1233 (TREE_OPERAND (datum, 0),
1234 build_component_ref (TREE_OPERAND (datum, 1), component),
1235 build_component_ref (TREE_OPERAND (datum, 2), component));
1238 /* See if there is a field or component with name COMPONENT. */
1240 if (code == RECORD_TYPE || code == UNION_TYPE)
1244 if (TYPE_SIZE (type) == 0)
1246 incomplete_type_error (NULL_TREE, type);
1247 return error_mark_node;
1250 field = lookup_field (type, component, &indirect);
1254 error (code == RECORD_TYPE
1255 ? "structure has no member named `%s'"
1256 : "union has no member named `%s'",
1257 IDENTIFIER_POINTER (component));
1258 return error_mark_node;
1260 if (TREE_TYPE (field) == error_mark_node)
1261 return error_mark_node;
1263 /* If FIELD was found buried within an anonymous union,
1264 make one COMPONENT_REF to get that anonymous union,
1265 then fall thru to make a second COMPONENT_REF to get FIELD. */
1268 ref = build (COMPONENT_REF, TREE_TYPE (indirect), datum, indirect);
1269 if (TREE_READONLY (datum) || TREE_READONLY (indirect))
1270 TREE_READONLY (ref) = 1;
1271 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (indirect))
1272 TREE_THIS_VOLATILE (ref) = 1;
1276 ref = build (COMPONENT_REF, TREE_TYPE (field), datum, field);
1278 if (TREE_READONLY (datum) || TREE_READONLY (field))
1279 TREE_READONLY (ref) = 1;
1280 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (field))
1281 TREE_THIS_VOLATILE (ref) = 1;
1285 else if (code != ERROR_MARK)
1286 error ("request for member `%s' in something not a structure or union",
1287 IDENTIFIER_POINTER (component));
1289 return error_mark_node;
1292 /* Given an expression PTR for a pointer, return an expression
1293 for the value pointed to.
1294 ERRORSTRING is the name of the operator to appear in error messages. */
1297 build_indirect_ref (ptr, errorstring)
1301 register tree pointer = default_conversion (ptr);
1302 register tree type = TREE_TYPE (pointer);
1304 if (TREE_CODE (type) == POINTER_TYPE)
1306 if (TREE_CODE (pointer) == ADDR_EXPR
1308 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1309 == TREE_TYPE (type)))
1310 return TREE_OPERAND (pointer, 0);
1313 tree t = TREE_TYPE (type);
1314 register tree ref = build1 (INDIRECT_REF,
1315 TYPE_MAIN_VARIANT (t), pointer);
1317 if (TYPE_SIZE (t) == 0 && TREE_CODE (t) != ARRAY_TYPE)
1319 error ("dereferencing pointer to incomplete type");
1320 return error_mark_node;
1322 if (TREE_CODE (t) == VOID_TYPE)
1323 warning ("dereferencing `void *' pointer");
1325 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1326 so that we get the proper error message if the result is used
1327 to assign to. Also, &* is supposed to be a no-op.
1328 And ANSI C seems to specify that the type of the result
1329 should be the const type. */
1330 /* A de-reference of a pointer to const is not a const. It is valid
1331 to change it via some other pointer. */
1332 TREE_READONLY (ref) = TYPE_READONLY (t);
1333 TREE_SIDE_EFFECTS (ref)
1334 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer) || flag_volatile;
1335 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1339 else if (TREE_CODE (pointer) != ERROR_MARK)
1340 error ("invalid type argument of `%s'", errorstring);
1341 return error_mark_node;
1344 /* This handles expressions of the form "a[i]", which denotes
1347 This is logically equivalent in C to *(a+i), but we may do it differently.
1348 If A is a variable or a member, we generate a primitive ARRAY_REF.
1349 This avoids forcing the array out of registers, and can work on
1350 arrays that are not lvalues (for example, members of structures returned
1354 build_array_ref (array, index)
1359 error ("subscript missing in array reference");
1360 return error_mark_node;
1363 if (TREE_TYPE (array) == error_mark_node
1364 || TREE_TYPE (index) == error_mark_node)
1365 return error_mark_node;
1367 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
1368 && TREE_CODE (array) != INDIRECT_REF)
1372 /* Subscripting with type char is likely to lose
1373 on a machine where chars are signed.
1374 So warn on any machine, but optionally.
1375 Don't warn for unsigned char since that type is safe.
1376 Don't warn for signed char because anyone who uses that
1377 must have done so deliberately. */
1378 if (warn_char_subscripts
1379 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1380 warning ("array subscript has type `char'");
1382 /* Apply default promotions *after* noticing character types. */
1383 index = default_conversion (index);
1385 /* Require integer *after* promotion, for sake of enums. */
1386 if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE)
1388 error ("array subscript is not an integer");
1389 return error_mark_node;
1392 /* An array that is indexed by a non-constant
1393 cannot be stored in a register; we must be able to do
1394 address arithmetic on its address.
1395 Likewise an array of elements of variable size. */
1396 if (TREE_CODE (index) != INTEGER_CST
1397 || (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))) != 0
1398 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1400 if (mark_addressable (array) == 0)
1401 return error_mark_node;
1403 /* An array that is indexed by a constant value which is not within
1404 the array bounds cannot be stored in a register either; because we
1405 would get a crash in store_bit_field/extract_bit_field when trying
1406 to access a non-existent part of the register. */
1407 if (TREE_CODE (index) == INTEGER_CST
1408 && TYPE_VALUES (TREE_TYPE (array))
1409 && ! int_fits_type_p (index, TYPE_VALUES (TREE_TYPE (array))))
1411 if (mark_addressable (array) == 0)
1412 return error_mark_node;
1415 if (pedantic && !lvalue_p (array))
1417 if (DECL_REGISTER (array))
1418 pedwarn ("ANSI C forbids subscripting `register' array");
1420 pedwarn ("ANSI C forbids subscripting non-lvalue array");
1426 while (TREE_CODE (foo) == COMPONENT_REF)
1427 foo = TREE_OPERAND (foo, 0);
1428 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
1429 pedwarn ("ANSI C forbids subscripting non-lvalue array");
1432 type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array)));
1433 rval = build (ARRAY_REF, type, array, index);
1434 /* Array ref is const/volatile if the array elements are
1435 or if the array is. */
1436 TREE_READONLY (rval)
1437 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1438 | TREE_READONLY (array));
1439 TREE_SIDE_EFFECTS (rval)
1440 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1441 | TREE_SIDE_EFFECTS (array));
1442 TREE_THIS_VOLATILE (rval)
1443 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1444 /* This was added by rms on 16 Nov 91.
1445 It fixes vol struct foo *a; a->elts[1]
1446 in an inline function.
1447 Hope it doesn't break something else. */
1448 | TREE_THIS_VOLATILE (array));
1449 return require_complete_type (fold (rval));
1453 tree ar = default_conversion (array);
1454 tree ind = default_conversion (index);
1456 /* Do the same warning check as above, but only on the part that's
1457 syntactically the index and only if it is also semantically
1459 if (warn_char_subscripts
1460 && TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE
1461 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1462 warning ("subscript has type `char'");
1464 /* Put the integer in IND to simplify error checking. */
1465 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
1472 if (ar == error_mark_node)
1475 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE
1476 || TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) == FUNCTION_TYPE)
1478 error ("subscripted value is neither array nor pointer");
1479 return error_mark_node;
1481 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
1483 error ("array subscript is not an integer");
1484 return error_mark_node;
1487 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0),
1492 /* Build a function call to function FUNCTION with parameters PARAMS.
1493 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1494 TREE_VALUE of each node is a parameter-expression.
1495 FUNCTION's data type may be a function type or a pointer-to-function. */
1498 build_function_call (function, params)
1499 tree function, params;
1501 register tree fntype, fundecl = 0;
1502 register tree coerced_params;
1503 tree name = NULL_TREE, assembler_name = NULL_TREE;
1505 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1506 STRIP_TYPE_NOPS (function);
1508 /* Convert anything with function type to a pointer-to-function. */
1509 if (TREE_CODE (function) == FUNCTION_DECL)
1511 name = DECL_NAME (function);
1512 assembler_name = DECL_ASSEMBLER_NAME (function);
1514 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1515 (because calling an inline function does not mean the function
1516 needs to be separately compiled). */
1517 fntype = build_type_variant (TREE_TYPE (function),
1518 TREE_READONLY (function),
1519 TREE_THIS_VOLATILE (function));
1521 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
1524 function = default_conversion (function);
1526 fntype = TREE_TYPE (function);
1528 if (TREE_CODE (fntype) == ERROR_MARK)
1529 return error_mark_node;
1531 if (!(TREE_CODE (fntype) == POINTER_TYPE
1532 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
1534 error ("called object is not a function");
1535 return error_mark_node;
1538 /* fntype now gets the type of function pointed to. */
1539 fntype = TREE_TYPE (fntype);
1541 /* Convert the parameters to the types declared in the
1542 function prototype, or apply default promotions. */
1545 = convert_arguments (TYPE_ARG_TYPES (fntype), params, name, fundecl);
1547 /* Check for errors in format strings. */
1549 if (warn_format && (name || assembler_name))
1550 check_function_format (name, assembler_name, coerced_params);
1552 /* Recognize certain built-in functions so we can make tree-codes
1553 other than CALL_EXPR. We do this when it enables fold-const.c
1554 to do something useful. */
1556 if (TREE_CODE (function) == ADDR_EXPR
1557 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
1558 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
1559 switch (DECL_FUNCTION_CODE (TREE_OPERAND (function, 0)))
1564 if (coerced_params == 0)
1565 return integer_zero_node;
1566 return build_unary_op (ABS_EXPR, TREE_VALUE (coerced_params), 0);
1570 register tree result
1571 = build (CALL_EXPR, TREE_TYPE (fntype),
1572 function, coerced_params, NULL_TREE);
1574 TREE_SIDE_EFFECTS (result) = 1;
1575 if (TREE_TYPE (result) == void_type_node)
1577 return require_complete_type (result);
1581 /* Convert the argument expressions in the list VALUES
1582 to the types in the list TYPELIST. The result is a list of converted
1583 argument expressions.
1585 If TYPELIST is exhausted, or when an element has NULL as its type,
1586 perform the default conversions.
1588 PARMLIST is the chain of parm decls for the function being called.
1589 It may be 0, if that info is not available.
1590 It is used only for generating error messages.
1592 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1594 This is also where warnings about wrong number of args are generated.
1596 Both VALUES and the returned value are chains of TREE_LIST nodes
1597 with the elements of the list in the TREE_VALUE slots of those nodes. */
1600 convert_arguments (typelist, values, name, fundecl)
1601 tree typelist, values, name, fundecl;
1603 register tree typetail, valtail;
1604 register tree result = NULL;
1607 /* Scan the given expressions and types, producing individual
1608 converted arguments and pushing them on RESULT in reverse order. */
1610 for (valtail = values, typetail = typelist, parmnum = 0;
1612 valtail = TREE_CHAIN (valtail), parmnum++)
1614 register tree type = typetail ? TREE_VALUE (typetail) : 0;
1615 register tree val = TREE_VALUE (valtail);
1617 if (type == void_type_node)
1620 error ("too many arguments to function `%s'",
1621 IDENTIFIER_POINTER (name));
1623 error ("too many arguments to function");
1627 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1628 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1629 to convert automatically to a pointer. */
1630 if (TREE_CODE (val) == NON_LVALUE_EXPR)
1631 val = TREE_OPERAND (val, 0);
1633 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
1634 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE)
1635 val = default_conversion (val);
1637 val = require_complete_type (val);
1641 /* Formal parm type is specified by a function prototype. */
1644 if (TYPE_SIZE (type) == 0)
1646 error ("type of formal parameter %d is incomplete", parmnum + 1);
1651 /* Optionally warn about conversions that
1652 differ from the default conversions. */
1653 if (warn_conversion)
1655 int formal_prec = TYPE_PRECISION (type);
1657 if (INTEGRAL_TYPE_P (type)
1658 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1659 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1660 else if (TREE_CODE (type) == COMPLEX_TYPE
1661 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1662 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1663 else if (TREE_CODE (type) == REAL_TYPE
1664 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1665 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1666 else if (TREE_CODE (type) == REAL_TYPE
1667 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
1668 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1669 /* ??? At some point, messages should be written about
1670 conversions between complex types, but that's too messy
1672 else if (TREE_CODE (type) == REAL_TYPE
1673 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1675 /* Warn if any argument is passed as `float',
1676 since without a prototype it would be `double'. */
1677 if (formal_prec == TYPE_PRECISION (float_type_node))
1678 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1680 /* Detect integer changing in width or signedness. */
1681 else if (INTEGRAL_TYPE_P (type)
1682 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1684 tree would_have_been = default_conversion (val);
1685 tree type1 = TREE_TYPE (would_have_been);
1687 if (TREE_CODE (type) == ENUMERAL_TYPE
1688 && type == TREE_TYPE (val))
1689 /* No warning if function asks for enum
1690 and the actual arg is that enum type. */
1692 else if (formal_prec != TYPE_PRECISION (type1))
1693 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1694 else if (TREE_UNSIGNED (type) == TREE_UNSIGNED (type1))
1696 /* Don't complain if the formal parameter type
1697 is an enum, because we can't tell now whether
1698 the value was an enum--even the same enum. */
1699 else if (TREE_CODE (type) == ENUMERAL_TYPE)
1701 else if (TREE_CODE (val) == INTEGER_CST
1702 && int_fits_type_p (val, type))
1703 /* Change in signedness doesn't matter
1704 if a constant value is unaffected. */
1706 /* Likewise for a constant in a NOP_EXPR. */
1707 else if (TREE_CODE (val) == NOP_EXPR
1708 && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST
1709 && int_fits_type_p (TREE_OPERAND (val, 0), type))
1711 #if 0 /* We never get such tree structure here. */
1712 else if (TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE
1713 && int_fits_type_p (TYPE_MIN_VALUE (TREE_TYPE (val)), type)
1714 && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE (val)), type))
1715 /* Change in signedness doesn't matter
1716 if an enum value is unaffected. */
1719 /* If the value is extended from a narrower
1720 unsigned type, it doesn't matter whether we
1721 pass it as signed or unsigned; the value
1722 certainly is the same either way. */
1723 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
1724 && TREE_UNSIGNED (TREE_TYPE (val)))
1726 else if (TREE_UNSIGNED (type))
1727 warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1);
1729 warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1);
1733 parmval = convert_for_assignment (type, val,
1734 (char *) 0, /* arg passing */
1735 fundecl, name, parmnum + 1);
1737 #ifdef PROMOTE_PROTOTYPES
1738 if ((TREE_CODE (type) == INTEGER_TYPE
1739 || TREE_CODE (type) == ENUMERAL_TYPE)
1740 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
1741 parmval = default_conversion (parmval);
1744 result = tree_cons (NULL_TREE, parmval, result);
1746 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
1747 && (TYPE_PRECISION (TREE_TYPE (val))
1748 < TYPE_PRECISION (double_type_node)))
1749 /* Convert `float' to `double'. */
1750 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
1752 /* Convert `short' and `char' to full-size `int'. */
1753 result = tree_cons (NULL_TREE, default_conversion (val), result);
1756 typetail = TREE_CHAIN (typetail);
1759 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
1762 error ("too few arguments to function `%s'",
1763 IDENTIFIER_POINTER (name));
1765 error ("too few arguments to function");
1768 return nreverse (result);
1771 /* This is the entry point used by the parser
1772 for binary operators in the input.
1773 In addition to constructing the expression,
1774 we check for operands that were written with other binary operators
1775 in a way that is likely to confuse the user. */
1778 parser_build_binary_op (code, arg1, arg2)
1779 enum tree_code code;
1782 tree result = build_binary_op (code, arg1, arg2, 1);
1785 char class1 = TREE_CODE_CLASS (TREE_CODE (arg1));
1786 char class2 = TREE_CODE_CLASS (TREE_CODE (arg2));
1787 enum tree_code code1 = ERROR_MARK;
1788 enum tree_code code2 = ERROR_MARK;
1790 if (class1 == 'e' || class1 == '1'
1791 || class1 == '2' || class1 == '<')
1792 code1 = C_EXP_ORIGINAL_CODE (arg1);
1793 if (class2 == 'e' || class2 == '1'
1794 || class2 == '2' || class2 == '<')
1795 code2 = C_EXP_ORIGINAL_CODE (arg2);
1797 /* Check for cases such as x+y<<z which users are likely
1798 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1799 is cleared to prevent these warnings. */
1800 if (warn_parentheses)
1802 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
1804 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1805 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1806 warning ("suggest parentheses around + or - inside shift");
1809 if (code == TRUTH_ORIF_EXPR)
1811 if (code1 == TRUTH_ANDIF_EXPR
1812 || code2 == TRUTH_ANDIF_EXPR)
1813 warning ("suggest parentheses around && within ||");
1816 if (code == BIT_IOR_EXPR)
1818 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
1819 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1820 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
1821 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1822 warning ("suggest parentheses around arithmetic in operand of |");
1823 /* Check cases like x|y==z */
1824 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1825 warning ("suggest parentheses around comparison in operand of |");
1828 if (code == BIT_XOR_EXPR)
1830 if (code1 == BIT_AND_EXPR
1831 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1832 || code2 == BIT_AND_EXPR
1833 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1834 warning ("suggest parentheses around arithmetic in operand of ^");
1835 /* Check cases like x^y==z */
1836 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1837 warning ("suggest parentheses around comparison in operand of ^");
1840 if (code == BIT_AND_EXPR)
1842 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1843 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1844 warning ("suggest parentheses around + or - in operand of &");
1845 /* Check cases like x&y==z */
1846 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1847 warning ("suggest parentheses around comparison in operand of &");
1851 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1852 if (TREE_CODE_CLASS (code) == '<' && extra_warnings
1853 && (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<'))
1854 warning ("comparisons like X<=Y<=Z do not have their mathematical meaning");
1856 unsigned_conversion_warning (result, arg1);
1857 unsigned_conversion_warning (result, arg2);
1858 overflow_warning (result);
1860 class = TREE_CODE_CLASS (TREE_CODE (result));
1862 /* Record the code that was specified in the source,
1863 for the sake of warnings about confusing nesting. */
1864 if (class == 'e' || class == '1'
1865 || class == '2' || class == '<')
1866 C_SET_EXP_ORIGINAL_CODE (result, code);
1869 int flag = TREE_CONSTANT (result);
1870 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1871 so that convert_for_assignment wouldn't strip it.
1872 That way, we got warnings for things like p = (1 - 1).
1873 But it turns out we should not get those warnings. */
1874 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
1875 C_SET_EXP_ORIGINAL_CODE (result, code);
1876 TREE_CONSTANT (result) = flag;
1882 /* Build a binary-operation expression without default conversions.
1883 CODE is the kind of expression to build.
1884 This function differs from `build' in several ways:
1885 the data type of the result is computed and recorded in it,
1886 warnings are generated if arg data types are invalid,
1887 special handling for addition and subtraction of pointers is known,
1888 and some optimization is done (operations on narrow ints
1889 are done in the narrower type when that gives the same result).
1890 Constant folding is also done before the result is returned.
1892 Note that the operands will never have enumeral types, or function
1893 or array types, because either they will have the default conversions
1894 performed or they have both just been converted to some other type in which
1895 the arithmetic is to be done. */
1898 build_binary_op (code, orig_op0, orig_op1, convert_p)
1899 enum tree_code code;
1900 tree orig_op0, orig_op1;
1904 register enum tree_code code0, code1;
1907 /* Expression code to give to the expression when it is built.
1908 Normally this is CODE, which is what the caller asked for,
1909 but in some special cases we change it. */
1910 register enum tree_code resultcode = code;
1912 /* Data type in which the computation is to be performed.
1913 In the simplest cases this is the common type of the arguments. */
1914 register tree result_type = NULL;
1916 /* Nonzero means operands have already been type-converted
1917 in whatever way is necessary.
1918 Zero means they need to be converted to RESULT_TYPE. */
1921 /* Nonzero means create the expression with this type, rather than
1923 tree build_type = 0;
1925 /* Nonzero means after finally constructing the expression
1926 convert it to this type. */
1927 tree final_type = 0;
1929 /* Nonzero if this is an operation like MIN or MAX which can
1930 safely be computed in short if both args are promoted shorts.
1931 Also implies COMMON.
1932 -1 indicates a bitwise operation; this makes a difference
1933 in the exact conditions for when it is safe to do the operation
1934 in a narrower mode. */
1937 /* Nonzero if this is a comparison operation;
1938 if both args are promoted shorts, compare the original shorts.
1939 Also implies COMMON. */
1940 int short_compare = 0;
1942 /* Nonzero if this is a right-shift operation, which can be computed on the
1943 original short and then promoted if the operand is a promoted short. */
1944 int short_shift = 0;
1946 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1951 op0 = default_conversion (orig_op0);
1952 op1 = default_conversion (orig_op1);
1960 type0 = TREE_TYPE (op0);
1961 type1 = TREE_TYPE (op1);
1963 /* The expression codes of the data types of the arguments tell us
1964 whether the arguments are integers, floating, pointers, etc. */
1965 code0 = TREE_CODE (type0);
1966 code1 = TREE_CODE (type1);
1968 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1969 STRIP_TYPE_NOPS (op0);
1970 STRIP_TYPE_NOPS (op1);
1972 /* If an error was already reported for one of the arguments,
1973 avoid reporting another error. */
1975 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
1976 return error_mark_node;
1981 /* Handle the pointer + int case. */
1982 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
1983 return pointer_int_sum (PLUS_EXPR, op0, op1);
1984 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
1985 return pointer_int_sum (PLUS_EXPR, op1, op0);
1991 /* Subtraction of two similar pointers.
1992 We must subtract them as integers, then divide by object size. */
1993 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
1994 && comp_target_types (type0, type1))
1995 return pointer_diff (op0, op1);
1996 /* Handle pointer minus int. Just like pointer plus int. */
1997 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
1998 return pointer_int_sum (MINUS_EXPR, op0, op1);
2007 case TRUNC_DIV_EXPR:
2009 case FLOOR_DIV_EXPR:
2010 case ROUND_DIV_EXPR:
2011 case EXACT_DIV_EXPR:
2012 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2013 || code0 == COMPLEX_TYPE)
2014 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2015 || code1 == COMPLEX_TYPE))
2017 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
2018 resultcode = RDIV_EXPR;
2021 /* Although it would be tempting to shorten always here, that
2022 loses on some targets, since the modulo instruction is
2023 undefined if the quotient can't be represented in the
2024 computation mode. We shorten only if unsigned or if
2025 dividing by something we know != -1. */
2026 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
2027 || (TREE_CODE (op1) == INTEGER_CST
2028 && (TREE_INT_CST_LOW (op1) != -1
2029 || TREE_INT_CST_HIGH (op1) != -1)));
2036 case BIT_ANDTC_EXPR:
2039 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2041 /* If one operand is a constant, and the other is a short type
2042 that has been converted to an int,
2043 really do the work in the short type and then convert the
2044 result to int. If we are lucky, the constant will be 0 or 1
2045 in the short type, making the entire operation go away. */
2046 if (TREE_CODE (op0) == INTEGER_CST
2047 && TREE_CODE (op1) == NOP_EXPR
2048 && TYPE_PRECISION (type1) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))
2049 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0))))
2051 final_type = result_type;
2052 op1 = TREE_OPERAND (op1, 0);
2053 result_type = TREE_TYPE (op1);
2055 if (TREE_CODE (op1) == INTEGER_CST
2056 && TREE_CODE (op0) == NOP_EXPR
2057 && TYPE_PRECISION (type0) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))
2058 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2060 final_type = result_type;
2061 op0 = TREE_OPERAND (op0, 0);
2062 result_type = TREE_TYPE (op0);
2066 case TRUNC_MOD_EXPR:
2067 case FLOOR_MOD_EXPR:
2068 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2070 /* Although it would be tempting to shorten always here, that loses
2071 on some targets, since the modulo instruction is undefined if the
2072 quotient can't be represented in the computation mode. We shorten
2073 only if unsigned or if dividing by something we know != -1. */
2074 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
2075 || (TREE_CODE (op1) == INTEGER_CST
2076 && (TREE_INT_CST_LOW (op1) != -1
2077 || TREE_INT_CST_HIGH (op1) != -1)));
2082 case TRUTH_ANDIF_EXPR:
2083 case TRUTH_ORIF_EXPR:
2084 case TRUTH_AND_EXPR:
2086 case TRUTH_XOR_EXPR:
2087 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
2088 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2089 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
2090 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2092 /* Result of these operations is always an int,
2093 but that does not mean the operands should be
2094 converted to ints! */
2095 result_type = integer_type_node;
2096 op0 = truthvalue_conversion (op0);
2097 op1 = truthvalue_conversion (op1);
2102 /* Shift operations: result has same type as first operand;
2103 always convert second operand to int.
2104 Also set SHORT_SHIFT if shifting rightward. */
2107 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2109 if (TREE_CODE (op1) == INTEGER_CST)
2111 if (tree_int_cst_sgn (op1) < 0)
2112 warning ("right shift count is negative");
2115 if (TREE_INT_CST_LOW (op1) | TREE_INT_CST_HIGH (op1))
2117 if (TREE_INT_CST_HIGH (op1) != 0
2118 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2119 >= TYPE_PRECISION (type0)))
2120 warning ("right shift count >= width of type");
2123 /* Use the type of the value to be shifted.
2124 This is what most traditional C compilers do. */
2125 result_type = type0;
2126 /* Unless traditional, convert the shift-count to an integer,
2127 regardless of size of value being shifted. */
2128 if (! flag_traditional)
2130 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2131 op1 = convert (integer_type_node, op1);
2132 /* Avoid converting op1 to result_type later. */
2139 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2141 if (TREE_CODE (op1) == INTEGER_CST)
2143 if (tree_int_cst_sgn (op1) < 0)
2144 warning ("left shift count is negative");
2145 else if (TREE_INT_CST_HIGH (op1) != 0
2146 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2147 >= TYPE_PRECISION (type0)))
2148 warning ("left shift count >= width of type");
2150 /* Use the type of the value to be shifted.
2151 This is what most traditional C compilers do. */
2152 result_type = type0;
2153 /* Unless traditional, convert the shift-count to an integer,
2154 regardless of size of value being shifted. */
2155 if (! flag_traditional)
2157 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2158 op1 = convert (integer_type_node, op1);
2159 /* Avoid converting op1 to result_type later. */
2167 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2169 if (TREE_CODE (op1) == INTEGER_CST)
2171 if (tree_int_cst_sgn (op1) < 0)
2172 warning ("shift count is negative");
2173 else if (TREE_INT_CST_HIGH (op1) != 0
2174 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2175 >= TYPE_PRECISION (type0)))
2176 warning ("shift count >= width of type");
2178 /* Use the type of the value to be shifted.
2179 This is what most traditional C compilers do. */
2180 result_type = type0;
2181 /* Unless traditional, convert the shift-count to an integer,
2182 regardless of size of value being shifted. */
2183 if (! flag_traditional)
2185 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2186 op1 = convert (integer_type_node, op1);
2187 /* Avoid converting op1 to result_type later. */
2195 /* Result of comparison is always int,
2196 but don't convert the args to int! */
2197 build_type = integer_type_node;
2198 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2199 || code0 == COMPLEX_TYPE)
2200 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2201 || code1 == COMPLEX_TYPE))
2203 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2205 register tree tt0 = TREE_TYPE (type0);
2206 register tree tt1 = TREE_TYPE (type1);
2207 /* Anything compares with void *. void * compares with anything.
2208 Otherwise, the targets must be compatible
2209 and both must be object or both incomplete. */
2210 if (comp_target_types (type0, type1))
2211 result_type = common_type (type0, type1);
2212 else if (TYPE_MAIN_VARIANT (tt0) == void_type_node)
2214 /* op0 != orig_op0 detects the case of something
2215 whose value is 0 but which isn't a valid null ptr const. */
2216 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
2217 && TREE_CODE (tt1) == FUNCTION_TYPE)
2218 pedwarn ("ANSI C forbids comparison of `void *' with function pointer");
2220 else if (TYPE_MAIN_VARIANT (tt1) == void_type_node)
2222 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
2223 && TREE_CODE (tt0) == FUNCTION_TYPE)
2224 pedwarn ("ANSI C forbids comparison of `void *' with function pointer");
2227 pedwarn ("comparison of distinct pointer types lacks a cast");
2229 if (result_type == NULL_TREE)
2230 result_type = ptr_type_node;
2232 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2233 && integer_zerop (op1))
2234 result_type = type0;
2235 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2236 && integer_zerop (op0))
2237 result_type = type1;
2238 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2240 result_type = type0;
2241 if (! flag_traditional)
2242 pedwarn ("comparison between pointer and integer");
2244 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2246 result_type = type1;
2247 if (! flag_traditional)
2248 pedwarn ("comparison between pointer and integer");
2254 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2255 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2257 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2259 if (comp_target_types (type0, type1))
2261 result_type = common_type (type0, type1);
2263 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2264 pedwarn ("ANSI C forbids ordered comparisons of pointers to functions");
2268 result_type = ptr_type_node;
2269 pedwarn ("comparison of distinct pointer types lacks a cast");
2278 build_type = integer_type_node;
2279 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2280 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2282 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2284 if (comp_target_types (type0, type1))
2286 result_type = common_type (type0, type1);
2287 if ((TYPE_SIZE (TREE_TYPE (type0)) != 0)
2288 != (TYPE_SIZE (TREE_TYPE (type1)) != 0))
2289 pedwarn ("comparison of complete and incomplete pointers");
2291 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2292 pedwarn ("ANSI C forbids ordered comparisons of pointers to functions");
2296 result_type = ptr_type_node;
2297 pedwarn ("comparison of distinct pointer types lacks a cast");
2300 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2301 && integer_zerop (op1))
2303 result_type = type0;
2304 if (pedantic || extra_warnings)
2305 pedwarn ("ordered comparison of pointer with integer zero");
2307 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2308 && integer_zerop (op0))
2310 result_type = type1;
2312 pedwarn ("ordered comparison of pointer with integer zero");
2314 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2316 result_type = type0;
2317 if (! flag_traditional)
2318 pedwarn ("comparison between pointer and integer");
2320 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2322 result_type = type1;
2323 if (! flag_traditional)
2324 pedwarn ("comparison between pointer and integer");
2329 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2331 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2333 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
2335 if (shorten || common || short_compare)
2336 result_type = common_type (type0, type1);
2338 /* For certain operations (which identify themselves by shorten != 0)
2339 if both args were extended from the same smaller type,
2340 do the arithmetic in that type and then extend.
2342 shorten !=0 and !=1 indicates a bitwise operation.
2343 For them, this optimization is safe only if
2344 both args are zero-extended or both are sign-extended.
2345 Otherwise, we might change the result.
2346 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2347 but calculated in (unsigned short) it would be (unsigned short)-1. */
2349 if (shorten && none_complex)
2351 int unsigned0, unsigned1;
2352 tree arg0 = get_narrower (op0, &unsigned0);
2353 tree arg1 = get_narrower (op1, &unsigned1);
2354 /* UNS is 1 if the operation to be done is an unsigned one. */
2355 int uns = TREE_UNSIGNED (result_type);
2358 final_type = result_type;
2360 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2361 but it *requires* conversion to FINAL_TYPE. */
2363 if ((TYPE_PRECISION (TREE_TYPE (op0))
2364 == TYPE_PRECISION (TREE_TYPE (arg0)))
2365 && TREE_TYPE (op0) != final_type)
2366 unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
2367 if ((TYPE_PRECISION (TREE_TYPE (op1))
2368 == TYPE_PRECISION (TREE_TYPE (arg1)))
2369 && TREE_TYPE (op1) != final_type)
2370 unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
2372 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2374 /* For bitwise operations, signedness of nominal type
2375 does not matter. Consider only how operands were extended. */
2379 /* Note that in all three cases below we refrain from optimizing
2380 an unsigned operation on sign-extended args.
2381 That would not be valid. */
2383 /* Both args variable: if both extended in same way
2384 from same width, do it in that width.
2385 Do it unsigned if args were zero-extended. */
2386 if ((TYPE_PRECISION (TREE_TYPE (arg0))
2387 < TYPE_PRECISION (result_type))
2388 && (TYPE_PRECISION (TREE_TYPE (arg1))
2389 == TYPE_PRECISION (TREE_TYPE (arg0)))
2390 && unsigned0 == unsigned1
2391 && (unsigned0 || !uns))
2393 = signed_or_unsigned_type (unsigned0,
2394 common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
2395 else if (TREE_CODE (arg0) == INTEGER_CST
2396 && (unsigned1 || !uns)
2397 && (TYPE_PRECISION (TREE_TYPE (arg1))
2398 < TYPE_PRECISION (result_type))
2399 && (type = signed_or_unsigned_type (unsigned1,
2401 int_fits_type_p (arg0, type)))
2403 else if (TREE_CODE (arg1) == INTEGER_CST
2404 && (unsigned0 || !uns)
2405 && (TYPE_PRECISION (TREE_TYPE (arg0))
2406 < TYPE_PRECISION (result_type))
2407 && (type = signed_or_unsigned_type (unsigned0,
2409 int_fits_type_p (arg1, type)))
2413 /* Shifts can be shortened if shifting right. */
2418 tree arg0 = get_narrower (op0, &unsigned_arg);
2420 final_type = result_type;
2422 if (arg0 == op0 && final_type == TREE_TYPE (op0))
2423 unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
2425 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
2426 /* We can shorten only if the shift count is less than the
2427 number of bits in the smaller type size. */
2428 && TREE_INT_CST_HIGH (op1) == 0
2429 && TYPE_PRECISION (TREE_TYPE (arg0)) > TREE_INT_CST_LOW (op1)
2430 /* If arg is sign-extended and then unsigned-shifted,
2431 we can simulate this with a signed shift in arg's type
2432 only if the extended result is at least twice as wide
2433 as the arg. Otherwise, the shift could use up all the
2434 ones made by sign-extension and bring in zeros.
2435 We can't optimize that case at all, but in most machines
2436 it never happens because available widths are 2**N. */
2437 && (!TREE_UNSIGNED (final_type)
2439 || 2 * TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (result_type)))
2441 /* Do an unsigned shift if the operand was zero-extended. */
2443 = signed_or_unsigned_type (unsigned_arg,
2445 /* Convert value-to-be-shifted to that type. */
2446 if (TREE_TYPE (op0) != result_type)
2447 op0 = convert (result_type, op0);
2452 /* Comparison operations are shortened too but differently.
2453 They identify themselves by setting short_compare = 1. */
2457 /* Don't write &op0, etc., because that would prevent op0
2458 from being kept in a register.
2459 Instead, make copies of the our local variables and
2460 pass the copies by reference, then copy them back afterward. */
2461 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
2462 enum tree_code xresultcode = resultcode;
2464 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
2467 op0 = xop0, op1 = xop1;
2469 resultcode = xresultcode;
2471 if (warn_sign_compare)
2473 int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0));
2474 int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1));
2476 int unsignedp0, unsignedp1;
2477 tree primop0 = get_narrower (op0, &unsignedp0);
2478 tree primop1 = get_narrower (op1, &unsignedp1);
2480 /* Avoid spurious warnings for comparison with enumerators. */
2484 STRIP_TYPE_NOPS (xop0);
2485 STRIP_TYPE_NOPS (xop1);
2487 /* Give warnings for comparisons between signed and unsigned
2488 quantities that may fail. */
2489 /* Do the checking based on the original operand trees, so that
2490 casts will be considered, but default promotions won't be. */
2492 /* Do not warn if the comparison is being done in a signed type,
2493 since the signed type will only be chosen if it can represent
2494 all the values of the unsigned type. */
2495 if (! TREE_UNSIGNED (result_type))
2497 /* Do not warn if both operands are unsigned. */
2498 else if (op0_signed == op1_signed)
2500 /* Do not warn if the signed quantity is an unsuffixed
2501 integer literal (or some static constant expression
2502 involving such literals) and it is non-negative. */
2503 else if ((op0_signed && TREE_CODE (xop0) == INTEGER_CST
2504 && tree_int_cst_sgn (xop0) >= 0)
2505 || (op1_signed && TREE_CODE (xop1) == INTEGER_CST
2506 && tree_int_cst_sgn (xop1) >= 0))
2508 /* Do not warn if the comparison is an equality operation,
2509 the unsigned quantity is an integral constant and it does
2510 not use the most significant bit of result_type. */
2511 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
2512 && ((op0_signed && TREE_CODE (xop1) == INTEGER_CST
2513 && int_fits_type_p (xop1, signed_type (result_type)))
2514 || (op1_signed && TREE_CODE (xop0) == INTEGER_CST
2515 && int_fits_type_p (xop0, signed_type (result_type)))))
2518 warning ("comparison between signed and unsigned");
2520 /* Warn if two unsigned values are being compared in a size
2521 larger than their original size, and one (and only one) is the
2522 result of a `~' operator. This comparison will always fail.
2524 Also warn if one operand is a constant, and the constant
2525 does not have all bits set that are set in the ~ operand
2526 when it is extended. */
2528 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
2529 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
2531 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
2532 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
2535 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
2538 if (TREE_CODE (primop0) == INTEGER_CST
2539 || TREE_CODE (primop1) == INTEGER_CST)
2542 long constant, mask;
2543 int unsignedp, bits;
2545 if (TREE_CODE (primop0) == INTEGER_CST)
2548 unsignedp = unsignedp1;
2549 constant = TREE_INT_CST_LOW (primop0);
2554 unsignedp = unsignedp0;
2555 constant = TREE_INT_CST_LOW (primop1);
2558 bits = TYPE_PRECISION (TREE_TYPE (primop));
2559 if (bits < TYPE_PRECISION (result_type)
2560 && bits < HOST_BITS_PER_LONG && unsignedp)
2562 mask = (~0L) << bits;
2563 if ((mask & constant) != mask)
2564 warning ("comparison of promoted ~unsigned with constant");
2567 else if (unsignedp0 && unsignedp1
2568 && (TYPE_PRECISION (TREE_TYPE (primop0))
2569 < TYPE_PRECISION (result_type))
2570 && (TYPE_PRECISION (TREE_TYPE (primop1))
2571 < TYPE_PRECISION (result_type)))
2572 warning ("comparison of promoted ~unsigned with unsigned");
2578 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2579 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2580 Then the expression will be built.
2581 It will be given type FINAL_TYPE if that is nonzero;
2582 otherwise, it will be given type RESULT_TYPE. */
2586 binary_op_error (code);
2587 return error_mark_node;
2592 if (TREE_TYPE (op0) != result_type)
2593 op0 = convert (result_type, op0);
2594 if (TREE_TYPE (op1) != result_type)
2595 op1 = convert (result_type, op1);
2598 if (build_type == NULL_TREE)
2599 build_type = result_type;
2602 register tree result = build (resultcode, build_type, op0, op1);
2603 register tree folded;
2605 folded = fold (result);
2606 if (folded == result)
2607 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2608 if (final_type != 0)
2609 return convert (final_type, folded);
2614 /* Return a tree for the sum or difference (RESULTCODE says which)
2615 of pointer PTROP and integer INTOP. */
2618 pointer_int_sum (resultcode, ptrop, intop)
2619 enum tree_code resultcode;
2620 register tree ptrop, intop;
2624 register tree result;
2625 register tree folded;
2627 /* The result is a pointer of the same type that is being added. */
2629 register tree result_type = TREE_TYPE (ptrop);
2631 if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
2633 if (pedantic || warn_pointer_arith)
2634 pedwarn ("pointer of type `void *' used in arithmetic");
2635 size_exp = integer_one_node;
2637 else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
2639 if (pedantic || warn_pointer_arith)
2640 pedwarn ("pointer to a function used in arithmetic");
2641 size_exp = integer_one_node;
2644 size_exp = c_size_in_bytes (TREE_TYPE (result_type));
2646 /* If what we are about to multiply by the size of the elements
2647 contains a constant term, apply distributive law
2648 and multiply that constant term separately.
2649 This helps produce common subexpressions. */
2651 if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
2652 && ! TREE_CONSTANT (intop)
2653 && TREE_CONSTANT (TREE_OPERAND (intop, 1))
2654 && TREE_CONSTANT (size_exp)
2655 /* If the constant comes from pointer subtraction,
2656 skip this optimization--it would cause an error. */
2657 && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE
2658 /* If the constant is unsigned, and smaller than the pointer size,
2659 then we must skip this optimization. This is because it could cause
2660 an overflow error if the constant is negative but INTOP is not. */
2661 && (! TREE_UNSIGNED (TREE_TYPE (intop))
2662 || (TYPE_PRECISION (TREE_TYPE (intop))
2663 == TYPE_PRECISION (TREE_TYPE (ptrop)))))
2665 enum tree_code subcode = resultcode;
2666 tree int_type = TREE_TYPE (intop);
2667 if (TREE_CODE (intop) == MINUS_EXPR)
2668 subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
2669 /* Convert both subexpression types to the type of intop,
2670 because weird cases involving pointer arithmetic
2671 can result in a sum or difference with different type args. */
2672 ptrop = build_binary_op (subcode, ptrop,
2673 convert (int_type, TREE_OPERAND (intop, 1)), 1);
2674 intop = convert (int_type, TREE_OPERAND (intop, 0));
2677 /* Convert the integer argument to a type the same size as sizetype
2678 so the multiply won't overflow spuriously. */
2680 if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype)
2681 || TREE_UNSIGNED (TREE_TYPE (intop)) != TREE_UNSIGNED (sizetype))
2682 intop = convert (type_for_size (TYPE_PRECISION (sizetype),
2683 TREE_UNSIGNED (sizetype)), intop);
2685 /* Replace the integer argument with a suitable product by the object size.
2686 Do this multiplication as signed, then convert to the appropriate
2687 pointer type (actually unsigned integral). */
2689 intop = convert (result_type,
2690 build_binary_op (MULT_EXPR, intop,
2691 convert (TREE_TYPE (intop), size_exp), 1));
2693 /* Create the sum or difference. */
2695 result = build (resultcode, result_type, ptrop, intop);
2697 folded = fold (result);
2698 if (folded == result)
2699 TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop);
2703 /* Return a tree for the difference of pointers OP0 and OP1.
2704 The resulting tree has type int. */
2707 pointer_diff (op0, op1)
2708 register tree op0, op1;
2710 register tree result, folded;
2711 tree restype = ptrdiff_type_node;
2713 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2715 if (pedantic || warn_pointer_arith)
2717 if (TREE_CODE (target_type) == VOID_TYPE)
2718 pedwarn ("pointer of type `void *' used in subtraction");
2719 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2720 pedwarn ("pointer to a function used in subtraction");
2723 /* First do the subtraction as integers;
2724 then drop through to build the divide operator.
2725 Do not do default conversions on the minus operator
2726 in case restype is a short type. */
2728 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2729 convert (restype, op1), 0);
2730 /* This generates an error if op1 is pointer to incomplete type. */
2731 if (TYPE_SIZE (TREE_TYPE (TREE_TYPE (op1))) == 0)
2732 error ("arithmetic on pointer to an incomplete type");
2734 /* This generates an error if op0 is pointer to incomplete type. */
2735 op1 = c_size_in_bytes (target_type);
2737 /* Divide by the size, in easiest possible way. */
2739 result = build (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2741 folded = fold (result);
2742 if (folded == result)
2743 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2747 /* Construct and perhaps optimize a tree representation
2748 for a unary operation. CODE, a tree_code, specifies the operation
2749 and XARG is the operand. NOCONVERT nonzero suppresses
2750 the default promotions (such as from short to int). */
2753 build_unary_op (code, xarg, noconvert)
2754 enum tree_code code;
2758 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2759 register tree arg = xarg;
2760 register tree argtype = 0;
2761 register enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2762 char *errstring = NULL;
2765 if (typecode == ERROR_MARK)
2766 return error_mark_node;
2767 if (typecode == ENUMERAL_TYPE)
2768 typecode = INTEGER_TYPE;
2773 /* This is used for unary plus, because a CONVERT_EXPR
2774 is enough to prevent anybody from looking inside for
2775 associativity, but won't generate any code. */
2776 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2777 || typecode == COMPLEX_TYPE))
2778 errstring = "wrong type argument to unary plus";
2779 else if (!noconvert)
2780 arg = default_conversion (arg);
2784 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2785 || typecode == COMPLEX_TYPE))
2786 errstring = "wrong type argument to unary minus";
2787 else if (!noconvert)
2788 arg = default_conversion (arg);
2792 if (typecode == COMPLEX_TYPE)
2796 arg = default_conversion (arg);
2798 else if (typecode != INTEGER_TYPE)
2799 errstring = "wrong type argument to bit-complement";
2800 else if (!noconvert)
2801 arg = default_conversion (arg);
2805 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2806 || typecode == COMPLEX_TYPE))
2807 errstring = "wrong type argument to abs";
2808 else if (!noconvert)
2809 arg = default_conversion (arg);
2813 /* Conjugating a real value is a no-op, but allow it anyway. */
2814 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2815 || typecode == COMPLEX_TYPE))
2816 errstring = "wrong type argument to conjugation";
2817 else if (!noconvert)
2818 arg = default_conversion (arg);
2821 case TRUTH_NOT_EXPR:
2822 if (typecode != INTEGER_TYPE
2823 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2824 && typecode != COMPLEX_TYPE
2825 /* These will convert to a pointer. */
2826 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2828 errstring = "wrong type argument to unary exclamation mark";
2831 arg = truthvalue_conversion (arg);
2832 return invert_truthvalue (arg);
2838 if (TREE_CODE (arg) == COMPLEX_CST)
2839 return TREE_REALPART (arg);
2840 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2841 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2846 if (TREE_CODE (arg) == COMPLEX_CST)
2847 return TREE_IMAGPART (arg);
2848 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2849 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2851 return convert (TREE_TYPE (arg), integer_zero_node);
2853 case PREINCREMENT_EXPR:
2854 case POSTINCREMENT_EXPR:
2855 case PREDECREMENT_EXPR:
2856 case POSTDECREMENT_EXPR:
2857 /* Handle complex lvalues (when permitted)
2858 by reduction to simpler cases. */
2860 val = unary_complex_lvalue (code, arg);
2864 /* Increment or decrement the real part of the value,
2865 and don't change the imaginary part. */
2866 if (typecode == COMPLEX_TYPE)
2870 arg = stabilize_reference (arg);
2871 real = build_unary_op (REALPART_EXPR, arg, 1);
2872 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2873 return build (COMPLEX_EXPR, TREE_TYPE (arg),
2874 build_unary_op (code, real, 1), imag);
2877 /* Report invalid types. */
2879 if (typecode != POINTER_TYPE
2880 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2882 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2883 errstring ="wrong type argument to increment";
2885 errstring ="wrong type argument to decrement";
2891 tree result_type = TREE_TYPE (arg);
2893 arg = get_unwidened (arg, 0);
2894 argtype = TREE_TYPE (arg);
2896 /* Compute the increment. */
2898 if (typecode == POINTER_TYPE)
2900 /* If pointer target is an undefined struct,
2901 we just cannot know how to do the arithmetic. */
2902 if (TYPE_SIZE (TREE_TYPE (result_type)) == 0)
2903 error ("%s of pointer to unknown structure",
2904 ((code == PREINCREMENT_EXPR
2905 || code == POSTINCREMENT_EXPR)
2906 ? "increment" : "decrement"));
2907 else if ((pedantic || warn_pointer_arith)
2908 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2909 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2910 pedwarn ("wrong type argument to %s",
2911 ((code == PREINCREMENT_EXPR
2912 || code == POSTINCREMENT_EXPR)
2913 ? "increment" : "decrement"));
2914 inc = c_size_in_bytes (TREE_TYPE (result_type));
2917 inc = integer_one_node;
2919 inc = convert (argtype, inc);
2921 /* Handle incrementing a cast-expression. */
2924 switch (TREE_CODE (arg))
2929 case FIX_TRUNC_EXPR:
2930 case FIX_FLOOR_EXPR:
2931 case FIX_ROUND_EXPR:
2933 pedantic_lvalue_warning (CONVERT_EXPR);
2934 /* If the real type has the same machine representation
2935 as the type it is cast to, we can make better output
2936 by adding directly to the inside of the cast. */
2937 if ((TREE_CODE (TREE_TYPE (arg))
2938 == TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0))))
2939 && (TYPE_MODE (TREE_TYPE (arg))
2940 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (arg, 0)))))
2941 arg = TREE_OPERAND (arg, 0);
2944 tree incremented, modify, value;
2945 arg = stabilize_reference (arg);
2946 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
2949 value = save_expr (arg);
2950 incremented = build (((code == PREINCREMENT_EXPR
2951 || code == POSTINCREMENT_EXPR)
2952 ? PLUS_EXPR : MINUS_EXPR),
2953 argtype, value, inc);
2954 TREE_SIDE_EFFECTS (incremented) = 1;
2955 modify = build_modify_expr (arg, NOP_EXPR, incremented);
2956 value = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
2957 TREE_USED (value) = 1;
2967 /* Complain about anything else that is not a true lvalue. */
2968 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2969 || code == POSTINCREMENT_EXPR)
2970 ? "increment" : "decrement")))
2971 return error_mark_node;
2973 /* Report a read-only lvalue. */
2974 if (TREE_READONLY (arg))
2975 readonly_warning (arg,
2976 ((code == PREINCREMENT_EXPR
2977 || code == POSTINCREMENT_EXPR)
2978 ? "increment" : "decrement"));
2980 val = build (code, TREE_TYPE (arg), arg, inc);
2981 TREE_SIDE_EFFECTS (val) = 1;
2982 val = convert (result_type, val);
2983 if (TREE_CODE (val) != code)
2984 TREE_NO_UNUSED_WARNING (val) = 1;
2989 /* Note that this operation never does default_conversion
2990 regardless of NOCONVERT. */
2992 /* Let &* cancel out to simplify resulting code. */
2993 if (TREE_CODE (arg) == INDIRECT_REF)
2995 /* Don't let this be an lvalue. */
2996 if (lvalue_p (TREE_OPERAND (arg, 0)))
2997 return non_lvalue (TREE_OPERAND (arg, 0));
2998 return TREE_OPERAND (arg, 0);
3001 /* For &x[y], return x+y */
3002 if (TREE_CODE (arg) == ARRAY_REF)
3004 if (mark_addressable (TREE_OPERAND (arg, 0)) == 0)
3005 return error_mark_node;
3006 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
3007 TREE_OPERAND (arg, 1), 1);
3010 /* Handle complex lvalues (when permitted)
3011 by reduction to simpler cases. */
3012 val = unary_complex_lvalue (code, arg);
3016 #if 0 /* Turned off because inconsistent;
3017 float f; *&(int)f = 3.4 stores in int format
3018 whereas (int)f = 3.4 stores in float format. */
3019 /* Address of a cast is just a cast of the address
3020 of the operand of the cast. */
3021 switch (TREE_CODE (arg))
3026 case FIX_TRUNC_EXPR:
3027 case FIX_FLOOR_EXPR:
3028 case FIX_ROUND_EXPR:
3031 pedwarn ("ANSI C forbids the address of a cast expression");
3032 return convert (build_pointer_type (TREE_TYPE (arg)),
3033 build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0),
3038 /* Allow the address of a constructor if all the elements
3040 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_CONSTANT (arg))
3042 /* Anything not already handled and not a true memory reference
3044 else if (typecode != FUNCTION_TYPE && !lvalue_or_else (arg, "unary `&'"))
3045 return error_mark_node;
3047 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3048 argtype = TREE_TYPE (arg);
3049 /* If the lvalue is const or volatile,
3050 merge that into the type that the address will point to. */
3051 if (TREE_CODE_CLASS (TREE_CODE (arg)) == 'd'
3052 || TREE_CODE_CLASS (TREE_CODE (arg)) == 'r')
3054 if (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg))
3055 argtype = c_build_type_variant (argtype,
3056 TREE_READONLY (arg),
3057 TREE_THIS_VOLATILE (arg));
3060 argtype = build_pointer_type (argtype);
3062 if (mark_addressable (arg) == 0)
3063 return error_mark_node;
3068 if (TREE_CODE (arg) == COMPONENT_REF)
3070 tree field = TREE_OPERAND (arg, 1);
3072 addr = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
3074 if (DECL_C_BIT_FIELD (field))
3076 error ("attempt to take address of bit-field structure member `%s'",
3077 IDENTIFIER_POINTER (DECL_NAME (field)));
3078 return error_mark_node;
3081 addr = convert (argtype, addr);
3083 if (! integer_zerop (DECL_FIELD_BITPOS (field)))
3086 = size_binop (EASY_DIV_EXPR, DECL_FIELD_BITPOS (field),
3087 size_int (BITS_PER_UNIT));
3088 int flag = TREE_CONSTANT (addr);
3089 addr = fold (build (PLUS_EXPR, argtype,
3090 addr, convert (argtype, offset)));
3091 TREE_CONSTANT (addr) = flag;
3095 addr = build1 (code, argtype, arg);
3097 /* Address of a static or external variable or
3098 file-scope function counts as a constant. */
3100 && ! (TREE_CODE (arg) == FUNCTION_DECL
3101 && DECL_CONTEXT (arg) != 0))
3102 TREE_CONSTANT (addr) = 1;
3110 argtype = TREE_TYPE (arg);
3111 return fold (build1 (code, argtype, arg));
3115 return error_mark_node;
3119 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3120 convert ARG with the same conversions in the same order
3121 and return the result. */
3124 convert_sequence (conversions, arg)
3128 switch (TREE_CODE (conversions))
3133 case FIX_TRUNC_EXPR:
3134 case FIX_FLOOR_EXPR:
3135 case FIX_ROUND_EXPR:
3137 return convert (TREE_TYPE (conversions),
3138 convert_sequence (TREE_OPERAND (conversions, 0),
3147 /* Return nonzero if REF is an lvalue valid for this language.
3148 Lvalues can be assigned, unless their type has TYPE_READONLY.
3149 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3155 register enum tree_code code = TREE_CODE (ref);
3162 return lvalue_p (TREE_OPERAND (ref, 0));
3173 if (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3174 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE)
3181 /* Return nonzero if REF is an lvalue valid for this language;
3182 otherwise, print an error message and return zero. */
3185 lvalue_or_else (ref, string)
3189 int win = lvalue_p (ref);
3191 error ("invalid lvalue in %s", string);
3195 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3196 for certain kinds of expressions which are not really lvalues
3197 but which we can accept as lvalues.
3199 If ARG is not a kind of expression we can handle, return zero. */
3202 unary_complex_lvalue (code, arg)
3203 enum tree_code code;
3206 /* Handle (a, b) used as an "lvalue". */
3207 if (TREE_CODE (arg) == COMPOUND_EXPR)
3209 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
3210 pedantic_lvalue_warning (COMPOUND_EXPR);
3211 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
3212 TREE_OPERAND (arg, 0), real_result);
3215 /* Handle (a ? b : c) used as an "lvalue". */
3216 if (TREE_CODE (arg) == COND_EXPR)
3218 pedantic_lvalue_warning (COND_EXPR);
3219 return (build_conditional_expr
3220 (TREE_OPERAND (arg, 0),
3221 build_unary_op (code, TREE_OPERAND (arg, 1), 0),
3222 build_unary_op (code, TREE_OPERAND (arg, 2), 0)));
3228 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3229 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3232 pedantic_lvalue_warning (code)
3233 enum tree_code code;
3236 pedwarn ("ANSI C forbids use of %s expressions as lvalues",
3237 code == COND_EXPR ? "conditional"
3238 : code == COMPOUND_EXPR ? "compound" : "cast");
3241 /* Warn about storing in something that is `const'. */
3244 readonly_warning (arg, string)
3249 strcpy (buf, string);
3251 /* Forbid assignments to iterators. */
3252 if (TREE_CODE (arg) == VAR_DECL && ITERATOR_P (arg))
3254 strcat (buf, " of iterator `%s'");
3255 pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (arg)));
3258 if (TREE_CODE (arg) == COMPONENT_REF)
3260 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3261 readonly_warning (TREE_OPERAND (arg, 0), string);
3264 strcat (buf, " of read-only member `%s'");
3265 pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1))));
3268 else if (TREE_CODE (arg) == VAR_DECL)
3270 strcat (buf, " of read-only variable `%s'");
3271 pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (arg)));
3275 pedwarn ("%s of read-only location", buf);
3279 /* Mark EXP saying that we need to be able to take the
3280 address of it; it should not be allocated in a register.
3281 Value is 1 if successful. */
3284 mark_addressable (exp)
3287 register tree x = exp;
3289 switch (TREE_CODE (x))
3292 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3294 error ("cannot take address of bitfield `%s'",
3295 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (x, 1))));
3299 /* ... fall through ... */
3305 x = TREE_OPERAND (x, 0);
3309 TREE_ADDRESSABLE (x) = 1;
3316 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
3317 && DECL_NONLOCAL (x))
3319 if (TREE_PUBLIC (x))
3321 error ("global register variable `%s' used in nested function",
3322 IDENTIFIER_POINTER (DECL_NAME (x)));
3325 pedwarn ("register variable `%s' used in nested function",
3326 IDENTIFIER_POINTER (DECL_NAME (x)));
3328 else if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x))
3330 if (TREE_PUBLIC (x))
3332 error ("address of global register variable `%s' requested",
3333 IDENTIFIER_POINTER (DECL_NAME (x)));
3337 /* If we are making this addressable due to its having
3338 volatile components, give a different error message. Also
3339 handle the case of an unnamed parameter by not trying
3340 to give the name. */
3342 else if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (x)))
3344 error ("cannot put object with volatile field into register");
3348 pedwarn ("address of register variable `%s' requested",
3349 IDENTIFIER_POINTER (DECL_NAME (x)));
3351 put_var_into_stack (x);
3355 TREE_ADDRESSABLE (x) = 1;
3356 #if 0 /* poplevel deals with this now. */
3357 if (DECL_CONTEXT (x) == 0)
3358 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
3366 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3369 build_conditional_expr (ifexp, op1, op2)
3370 tree ifexp, op1, op2;
3372 register tree type1;
3373 register tree type2;
3374 register enum tree_code code1;
3375 register enum tree_code code2;
3376 register tree result_type = NULL;
3377 tree orig_op1 = op1, orig_op2 = op2;
3379 /* If second operand is omitted, it is the same as the first one;
3380 make sure it is calculated only once. */
3384 pedwarn ("ANSI C forbids omitting the middle term of a ?: expression");
3385 ifexp = orig_op1 = op1 = save_expr (ifexp);
3388 ifexp = truthvalue_conversion (default_conversion (ifexp));
3390 #if 0 /* Produces wrong result if within sizeof. */
3391 /* Don't promote the operands separately if they promote
3392 the same way. Return the unpromoted type and let the combined
3393 value get promoted if necessary. */
3395 if (TREE_TYPE (op1) == TREE_TYPE (op2)
3396 && TREE_CODE (TREE_TYPE (op1)) != ARRAY_TYPE
3397 && TREE_CODE (TREE_TYPE (op1)) != ENUMERAL_TYPE
3398 && TREE_CODE (TREE_TYPE (op1)) != FUNCTION_TYPE)
3400 if (TREE_CODE (ifexp) == INTEGER_CST)
3401 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3403 return fold (build (COND_EXPR, TREE_TYPE (op1), ifexp, op1, op2));
3407 /* Promote both alternatives. */
3409 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3410 op1 = default_conversion (op1);
3411 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3412 op2 = default_conversion (op2);
3414 if (TREE_CODE (ifexp) == ERROR_MARK
3415 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3416 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3417 return error_mark_node;
3419 type1 = TREE_TYPE (op1);
3420 code1 = TREE_CODE (type1);
3421 type2 = TREE_TYPE (op2);
3422 code2 = TREE_CODE (type2);
3424 /* Quickly detect the usual case where op1 and op2 have the same type
3426 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3429 result_type = type1;
3431 result_type = TYPE_MAIN_VARIANT (type1);
3433 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE)
3434 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE))
3436 result_type = common_type (type1, type2);
3438 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3440 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3441 pedwarn ("ANSI C forbids conditional expr with only one void side");
3442 result_type = void_type_node;
3444 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3446 if (comp_target_types (type1, type2))
3447 result_type = common_type (type1, type2);
3448 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
3449 && TREE_CODE (orig_op1) != NOP_EXPR)
3450 result_type = qualify_type (type2, type1);
3451 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
3452 && TREE_CODE (orig_op2) != NOP_EXPR)
3453 result_type = qualify_type (type1, type2);
3454 else if (TYPE_MAIN_VARIANT (TREE_TYPE (type1)) == void_type_node)
3456 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3457 pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer");
3458 result_type = qualify_type (type1, type2);
3460 else if (TYPE_MAIN_VARIANT (TREE_TYPE (type2)) == void_type_node)
3462 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3463 pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer");
3464 result_type = qualify_type (type2, type1);
3468 pedwarn ("pointer type mismatch in conditional expression");
3469 result_type = build_pointer_type (void_type_node);
3472 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3474 if (! integer_zerop (op2))
3475 pedwarn ("pointer/integer type mismatch in conditional expression");
3478 op2 = null_pointer_node;
3479 #if 0 /* The spec seems to say this is permitted. */
3480 if (pedantic && TREE_CODE (type1) == FUNCTION_TYPE)
3481 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3484 result_type = type1;
3486 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3488 if (!integer_zerop (op1))
3489 pedwarn ("pointer/integer type mismatch in conditional expression");
3492 op1 = null_pointer_node;
3493 #if 0 /* The spec seems to say this is permitted. */
3494 if (pedantic && TREE_CODE (type2) == FUNCTION_TYPE)
3495 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3498 result_type = type2;
3503 if (flag_cond_mismatch)
3504 result_type = void_type_node;
3507 error ("type mismatch in conditional expression");
3508 return error_mark_node;
3512 /* Merge const and volatile flags of the incoming types. */
3514 = build_type_variant (result_type,
3515 TREE_READONLY (op1) || TREE_READONLY (op2),
3516 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3518 if (result_type != TREE_TYPE (op1))
3519 op1 = convert_and_check (result_type, op1);
3520 if (result_type != TREE_TYPE (op2))
3521 op2 = convert_and_check (result_type, op2);
3524 if (code1 == RECORD_TYPE || code1 == UNION_TYPE)
3526 result_type = TREE_TYPE (op1);
3527 if (TREE_CONSTANT (ifexp))
3528 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3530 if (TYPE_MODE (result_type) == BLKmode)
3532 register tree tempvar
3533 = build_decl (VAR_DECL, NULL_TREE, result_type);
3534 register tree xop1 = build_modify_expr (tempvar, op1);
3535 register tree xop2 = build_modify_expr (tempvar, op2);
3536 register tree result = fold (build (COND_EXPR, result_type,
3537 ifexp, xop1, xop2));
3539 layout_decl (tempvar, TYPE_ALIGN (result_type));
3540 /* No way to handle variable-sized objects here.
3541 I fear that the entire handling of BLKmode conditional exprs
3542 needs to be redone. */
3543 if (TREE_CODE (DECL_SIZE (tempvar)) != INTEGER_CST)
3546 = assign_stack_local (DECL_MODE (tempvar),
3547 (TREE_INT_CST_LOW (DECL_SIZE (tempvar))
3548 + BITS_PER_UNIT - 1)
3552 TREE_SIDE_EFFECTS (result)
3553 = TREE_SIDE_EFFECTS (ifexp) | TREE_SIDE_EFFECTS (op1)
3554 | TREE_SIDE_EFFECTS (op2);
3555 return build (COMPOUND_EXPR, result_type, result, tempvar);
3560 if (TREE_CODE (ifexp) == INTEGER_CST)
3561 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3563 return fold (build (COND_EXPR, result_type, ifexp, op1, op2));
3566 /* Given a list of expressions, return a compound expression
3567 that performs them all and returns the value of the last of them. */
3570 build_compound_expr (list)
3573 return internal_build_compound_expr (list, TRUE);
3577 internal_build_compound_expr (list, first_p)
3583 if (TREE_CHAIN (list) == 0)
3585 #if 0 /* If something inside inhibited lvalueness, we should not override. */
3586 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3588 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3589 if (TREE_CODE (list) == NON_LVALUE_EXPR)
3590 list = TREE_OPERAND (list, 0);
3593 /* Don't let (0, 0) be null pointer constant. */
3594 if (!first_p && integer_zerop (TREE_VALUE (list)))
3595 return non_lvalue (TREE_VALUE (list));
3596 return TREE_VALUE (list);
3599 if (TREE_CHAIN (list) != 0 && TREE_CHAIN (TREE_CHAIN (list)) == 0)
3601 /* Convert arrays to pointers when there really is a comma operator. */
3602 if (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (list)))) == ARRAY_TYPE)
3603 TREE_VALUE (TREE_CHAIN (list))
3604 = default_conversion (TREE_VALUE (TREE_CHAIN (list)));
3607 rest = internal_build_compound_expr (TREE_CHAIN (list), FALSE);
3609 if (! TREE_SIDE_EFFECTS (TREE_VALUE (list)))
3611 /* The left-hand operand of a comma expression is like an expression
3612 statement: with -W or -Wunused, we should warn if it doesn't have
3613 any side-effects, unless it was explicitly cast to (void). */
3614 if ((extra_warnings || warn_unused)
3615 && ! (TREE_CODE (TREE_VALUE (list)) == CONVERT_EXPR
3616 && TREE_TYPE (TREE_VALUE (list)) == void_type_node))
3617 warning ("left-hand operand of comma expression has no effect");
3619 /* When pedantic, a compound expression can be neither an lvalue
3620 nor an integer constant expression. */
3625 /* With -Wunused, we should also warn if the left-hand operand does have
3626 side-effects, but computes a value which is not used. For example, in
3627 `foo() + bar(), baz()' the result of the `+' operator is not used,
3628 so we should issue a warning. */
3629 else if (warn_unused)
3630 warn_if_unused_value (TREE_VALUE (list));
3632 return build (COMPOUND_EXPR, TREE_TYPE (rest), TREE_VALUE (list), rest);
3635 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3638 build_c_cast (type, expr)
3642 register tree value = expr;
3644 if (type == error_mark_node || expr == error_mark_node)
3645 return error_mark_node;
3646 type = TYPE_MAIN_VARIANT (type);
3649 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3650 if (TREE_CODE (value) == NON_LVALUE_EXPR)
3651 value = TREE_OPERAND (value, 0);
3654 if (TREE_CODE (type) == ARRAY_TYPE)
3656 error ("cast specifies array type");
3657 return error_mark_node;
3660 if (TREE_CODE (type) == FUNCTION_TYPE)
3662 error ("cast specifies function type");
3663 return error_mark_node;
3666 if (type == TREE_TYPE (value))
3670 if (TREE_CODE (type) == RECORD_TYPE
3671 || TREE_CODE (type) == UNION_TYPE)
3672 pedwarn ("ANSI C forbids casting nonscalar to the same type");
3675 else if (TREE_CODE (type) == UNION_TYPE)
3678 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
3679 || TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE)
3680 value = default_conversion (value);
3682 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3683 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3684 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3693 pedwarn ("ANSI C forbids casts to union type");
3694 if (TYPE_NAME (type) != 0)
3696 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
3697 name = IDENTIFIER_POINTER (TYPE_NAME (type));
3699 name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));
3703 t = digest_init (type, build (CONSTRUCTOR, type, NULL_TREE,
3704 build_tree_list (field, value)),
3706 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3709 error ("cast to union type from type not present in union");
3710 return error_mark_node;
3716 /* If casting to void, avoid the error that would come
3717 from default_conversion in the case of a non-lvalue array. */
3718 if (type == void_type_node)
3719 return build1 (CONVERT_EXPR, type, value);
3721 /* Convert functions and arrays to pointers,
3722 but don't convert any other types. */
3723 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
3724 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE)
3725 value = default_conversion (value);
3726 otype = TREE_TYPE (value);
3728 /* Optionally warn about potentially worrisome casts. */
3731 && TREE_CODE (type) == POINTER_TYPE
3732 && TREE_CODE (otype) == POINTER_TYPE)
3734 if (TYPE_VOLATILE (TREE_TYPE (otype))
3735 && ! TYPE_VOLATILE (TREE_TYPE (type)))
3736 pedwarn ("cast discards `volatile' from pointer target type");
3737 if (TYPE_READONLY (TREE_TYPE (otype))
3738 && ! TYPE_READONLY (TREE_TYPE (type)))
3739 pedwarn ("cast discards `const' from pointer target type");
3742 /* Warn about possible alignment problems. */
3743 if (STRICT_ALIGNMENT && warn_cast_align
3744 && TREE_CODE (type) == POINTER_TYPE
3745 && TREE_CODE (otype) == POINTER_TYPE
3746 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3747 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3748 /* Don't warn about opaque types, where the actual alignment
3749 restriction is unknown. */
3750 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3751 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3752 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3753 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3754 warning ("cast increases required alignment of target type");
3756 if (TREE_CODE (type) == INTEGER_TYPE
3757 && TREE_CODE (otype) == POINTER_TYPE
3758 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3759 && !TREE_CONSTANT (value))
3760 warning ("cast from pointer to integer of different size");
3762 if (warn_bad_function_cast
3763 && TREE_CODE (value) == CALL_EXPR
3764 && TREE_CODE (type) != TREE_CODE (otype))
3765 warning ("cast does not match function type");
3767 if (TREE_CODE (type) == POINTER_TYPE
3768 && TREE_CODE (otype) == INTEGER_TYPE
3769 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3771 /* Don't warn about converting 0 to pointer,
3772 provided the 0 was explicit--not cast or made by folding. */
3773 && !(TREE_CODE (value) == INTEGER_CST && integer_zerop (value))
3775 /* Don't warn about converting any constant. */
3776 && !TREE_CONSTANT (value))
3777 warning ("cast to pointer from integer of different size");
3780 value = convert (type, value);
3782 /* Ignore any integer overflow caused by the cast. */
3783 if (TREE_CODE (value) == INTEGER_CST)
3785 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3786 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3790 /* Pedantically, don't ley (void *) (FOO *) 0 be a null pointer constant. */
3791 if (pedantic && TREE_CODE (value) == INTEGER_CST
3792 && TREE_CODE (expr) == INTEGER_CST
3793 && TREE_CODE (TREE_TYPE (expr)) != INTEGER_TYPE)
3794 value = non_lvalue (value);
3796 /* If pedantic, don't let a cast be an lvalue. */
3797 if (value == expr && pedantic)
3798 value = non_lvalue (value);
3803 /* Build an assignment expression of lvalue LHS from value RHS.
3804 MODIFYCODE is the code for a binary operator that we use
3805 to combine the old value of LHS with RHS to get the new value.
3806 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3809 build_modify_expr (lhs, modifycode, rhs)
3811 enum tree_code modifycode;
3813 register tree result;
3815 tree lhstype = TREE_TYPE (lhs);
3816 tree olhstype = lhstype;
3818 /* Types that aren't fully specified cannot be used in assignments. */
3819 lhs = require_complete_type (lhs);
3821 /* Avoid duplicate error messages from operands that had errors. */
3822 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3823 return error_mark_node;
3825 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3826 /* Do not use STRIP_NOPS here. We do not want an enumerator
3827 whose value is 0 to count as a null pointer constant. */
3828 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3829 rhs = TREE_OPERAND (rhs, 0);
3833 /* Handle control structure constructs used as "lvalues". */
3835 switch (TREE_CODE (lhs))
3837 /* Handle (a, b) used as an "lvalue". */
3839 pedantic_lvalue_warning (COMPOUND_EXPR);
3840 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
3842 if (TREE_CODE (newrhs) == ERROR_MARK)
3843 return error_mark_node;
3844 return build (COMPOUND_EXPR, lhstype,
3845 TREE_OPERAND (lhs, 0), newrhs);
3847 /* Handle (a ? b : c) used as an "lvalue". */
3849 pedantic_lvalue_warning (COND_EXPR);
3850 rhs = save_expr (rhs);
3852 /* Produce (a ? (b = rhs) : (c = rhs))
3853 except that the RHS goes through a save-expr
3854 so the code to compute it is only emitted once. */
3856 = build_conditional_expr (TREE_OPERAND (lhs, 0),
3857 build_modify_expr (TREE_OPERAND (lhs, 1),
3859 build_modify_expr (TREE_OPERAND (lhs, 2),
3861 if (TREE_CODE (cond) == ERROR_MARK)
3863 /* Make sure the code to compute the rhs comes out
3864 before the split. */
3865 return build (COMPOUND_EXPR, TREE_TYPE (lhs),
3866 /* But cast it to void to avoid an "unused" error. */
3867 convert (void_type_node, rhs), cond);
3871 /* If a binary op has been requested, combine the old LHS value with the RHS
3872 producing the value we should actually store into the LHS. */
3874 if (modifycode != NOP_EXPR)
3876 lhs = stabilize_reference (lhs);
3877 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3880 /* Handle a cast used as an "lvalue".
3881 We have already performed any binary operator using the value as cast.
3882 Now convert the result to the cast type of the lhs,
3883 and then true type of the lhs and store it there;
3884 then convert result back to the cast type to be the value
3885 of the assignment. */
3887 switch (TREE_CODE (lhs))
3892 case FIX_TRUNC_EXPR:
3893 case FIX_FLOOR_EXPR:
3894 case FIX_ROUND_EXPR:
3896 if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
3897 || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE)
3898 newrhs = default_conversion (newrhs);
3900 tree inner_lhs = TREE_OPERAND (lhs, 0);
3902 result = build_modify_expr (inner_lhs, NOP_EXPR,
3903 convert (TREE_TYPE (inner_lhs),
3904 convert (lhstype, newrhs)));
3905 if (TREE_CODE (result) == ERROR_MARK)
3907 pedantic_lvalue_warning (CONVERT_EXPR);
3908 return convert (TREE_TYPE (lhs), result);
3912 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3913 Reject anything strange now. */
3915 if (!lvalue_or_else (lhs, "assignment"))
3916 return error_mark_node;
3918 /* Warn about storing in something that is `const'. */
3920 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3921 || ((TREE_CODE (lhstype) == RECORD_TYPE
3922 || TREE_CODE (lhstype) == UNION_TYPE)
3923 && C_TYPE_FIELDS_READONLY (lhstype)))
3924 readonly_warning (lhs, "assignment");
3926 /* If storing into a structure or union member,
3927 it has probably been given type `int'.
3928 Compute the type that would go with
3929 the actual amount of storage the member occupies. */
3931 if (TREE_CODE (lhs) == COMPONENT_REF
3932 && (TREE_CODE (lhstype) == INTEGER_TYPE
3933 || TREE_CODE (lhstype) == REAL_TYPE
3934 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3935 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3937 /* If storing in a field that is in actuality a short or narrower than one,
3938 we must store in the field in its actual type. */
3940 if (lhstype != TREE_TYPE (lhs))
3942 lhs = copy_node (lhs);
3943 TREE_TYPE (lhs) = lhstype;
3946 /* Convert new value to destination type. */
3948 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
3949 NULL_TREE, NULL_TREE, 0);
3950 if (TREE_CODE (newrhs) == ERROR_MARK)
3951 return error_mark_node;
3953 result = build (MODIFY_EXPR, lhstype, lhs, newrhs);
3954 TREE_SIDE_EFFECTS (result) = 1;
3956 /* If we got the LHS in a different type for storing in,
3957 convert the result back to the nominal type of LHS
3958 so that the value we return always has the same type
3959 as the LHS argument. */
3961 if (olhstype == TREE_TYPE (result))
3963 return convert_for_assignment (olhstype, result, "assignment",
3964 NULL_TREE, NULL_TREE, 0);
3967 /* Convert value RHS to type TYPE as preparation for an assignment
3968 to an lvalue of type TYPE.
3969 The real work of conversion is done by `convert'.
3970 The purpose of this function is to generate error messages
3971 for assignments that are not allowed in C.
3972 ERRTYPE is a string to use in error messages:
3973 "assignment", "return", etc. If it is null, this is parameter passing
3974 for a function call (and different error messages are output). Otherwise,
3975 it may be a name stored in the spelling stack and interpreted by
3978 FUNNAME is the name of the function being called,
3979 as an IDENTIFIER_NODE, or null.
3980 PARMNUM is the number of the argument, for printing in error messages. */
3983 convert_for_assignment (type, rhs, errtype, fundecl, funname, parmnum)
3986 tree fundecl, funname;
3989 register enum tree_code codel = TREE_CODE (type);
3990 register tree rhstype;
3991 register enum tree_code coder;
3993 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3994 /* Do not use STRIP_NOPS here. We do not want an enumerator
3995 whose value is 0 to count as a null pointer constant. */
3996 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3997 rhs = TREE_OPERAND (rhs, 0);
3999 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
4000 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
4001 rhs = default_conversion (rhs);
4002 else if (optimize && TREE_CODE (rhs) == VAR_DECL)
4003 rhs = decl_constant_value (rhs);
4005 rhstype = TREE_TYPE (rhs);
4006 coder = TREE_CODE (rhstype);
4008 if (coder == ERROR_MARK)
4009 return error_mark_node;
4011 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
4013 overflow_warning (rhs);
4014 /* Check for Objective-C protocols. This will issue a warning if
4015 there are protocol violations. No need to use the return value. */
4016 maybe_objc_comptypes (type, rhstype, 0);
4020 if (coder == VOID_TYPE)
4022 error ("void value not ignored as it ought to be");
4023 return error_mark_node;
4025 /* Arithmetic types all interconvert, and enum is treated like int. */
4026 if ((codel == INTEGER_TYPE || codel == REAL_TYPE || codel == ENUMERAL_TYPE
4027 || codel == COMPLEX_TYPE)
4028 && (coder == INTEGER_TYPE || coder == REAL_TYPE || coder == ENUMERAL_TYPE
4029 || coder == COMPLEX_TYPE))
4030 return convert_and_check (type, rhs);
4032 /* Conversion to a transparent union from its member types.
4033 This applies only to function arguments. */
4034 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type) && ! errtype)
4037 tree marginal_memb_type = 0;
4039 for (memb_types = TYPE_FIELDS (type); memb_types;
4040 memb_types = TREE_CHAIN (memb_types))
4042 tree memb_type = TREE_TYPE (memb_types);
4044 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
4045 TYPE_MAIN_VARIANT (rhstype)))
4048 if (TREE_CODE (memb_type) != POINTER_TYPE)
4051 if (coder == POINTER_TYPE)
4053 register tree ttl = TREE_TYPE (memb_type);
4054 register tree ttr = TREE_TYPE (rhstype);
4056 /* Any non-function converts to a [const][volatile] void *
4057 and vice versa; otherwise, targets must be the same.
4058 Meanwhile, the lhs target must have all the qualifiers of
4060 if (TYPE_MAIN_VARIANT (ttl) == void_type_node
4061 || TYPE_MAIN_VARIANT (ttr) == void_type_node
4062 || comp_target_types (memb_type, rhstype))
4064 /* If this type won't generate any warnings, use it. */
4065 if ((TREE_CODE (ttr) == FUNCTION_TYPE
4066 && TREE_CODE (ttl) == FUNCTION_TYPE)
4067 ? ((! TYPE_READONLY (ttl) | TYPE_READONLY (ttr))
4068 & (! TYPE_VOLATILE (ttl) | TYPE_VOLATILE (ttr)))
4069 : ((TYPE_READONLY (ttl) | ! TYPE_READONLY (ttr))
4070 & (TYPE_VOLATILE (ttl) | ! TYPE_VOLATILE (ttr))))
4073 /* Keep looking for a better type, but remember this one. */
4074 if (! marginal_memb_type)
4075 marginal_memb_type = memb_type;
4079 /* Can convert integer zero to any pointer type. */
4080 if (integer_zerop (rhs)
4081 || (TREE_CODE (rhs) == NOP_EXPR
4082 && integer_zerop (TREE_OPERAND (rhs, 0))))
4084 rhs = null_pointer_node;
4089 if (memb_types || marginal_memb_type)
4093 /* We have only a marginally acceptable member type;
4094 it needs a warning. */
4095 register tree ttl = TREE_TYPE (marginal_memb_type);
4096 register tree ttr = TREE_TYPE (rhstype);
4098 /* Const and volatile mean something different for function
4099 types, so the usual warnings are not appropriate. */
4100 if (TREE_CODE (ttr) == FUNCTION_TYPE
4101 && TREE_CODE (ttl) == FUNCTION_TYPE)
4103 /* Because const and volatile on functions are
4104 restrictions that say the function will not do
4105 certain things, it is okay to use a const or volatile
4106 function where an ordinary one is wanted, but not
4108 if (TYPE_READONLY (ttl) && ! TYPE_READONLY (ttr))
4109 warn_for_assignment ("%s makes `const *' function pointer from non-const",
4110 get_spelling (errtype), funname,
4112 if (TYPE_VOLATILE (ttl) && ! TYPE_VOLATILE (ttr))
4113 warn_for_assignment ("%s makes `volatile *' function pointer from non-volatile",
4114 get_spelling (errtype), funname,
4119 if (! TYPE_READONLY (ttl) && TYPE_READONLY (ttr))
4120 warn_for_assignment ("%s discards `const' from pointer target type",
4121 get_spelling (errtype), funname,
4123 if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr))
4124 warn_for_assignment ("%s discards `volatile' from pointer target type",
4125 get_spelling (errtype), funname,
4130 if (pedantic && ! DECL_IN_SYSTEM_HEADER (fundecl))
4131 pedwarn ("ANSI C prohibits argument conversion to union type");
4133 return build1 (NOP_EXPR, type, rhs);
4137 /* Conversions among pointers */
4138 else if (codel == POINTER_TYPE && coder == POINTER_TYPE)
4140 register tree ttl = TREE_TYPE (type);
4141 register tree ttr = TREE_TYPE (rhstype);
4143 /* Any non-function converts to a [const][volatile] void *
4144 and vice versa; otherwise, targets must be the same.
4145 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4146 if (TYPE_MAIN_VARIANT (ttl) == void_type_node
4147 || TYPE_MAIN_VARIANT (ttr) == void_type_node
4148 || comp_target_types (type, rhstype)
4149 || (unsigned_type (TYPE_MAIN_VARIANT (ttl))
4150 == unsigned_type (TYPE_MAIN_VARIANT (ttr))))
4153 && ((TYPE_MAIN_VARIANT (ttl) == void_type_node
4154 && TREE_CODE (ttr) == FUNCTION_TYPE)
4156 (TYPE_MAIN_VARIANT (ttr) == void_type_node
4157 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4158 which are not ANSI null ptr constants. */
4159 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
4160 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4161 warn_for_assignment ("ANSI forbids %s between function pointer and `void *'",
4162 get_spelling (errtype), funname, parmnum);
4163 /* Const and volatile mean something different for function types,
4164 so the usual warnings are not appropriate. */
4165 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4166 && TREE_CODE (ttl) != FUNCTION_TYPE)
4168 if (! TYPE_READONLY (ttl) && TYPE_READONLY (ttr))
4169 warn_for_assignment ("%s discards `const' from pointer target type",
4170 get_spelling (errtype), funname, parmnum);
4171 else if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr))
4172 warn_for_assignment ("%s discards `volatile' from pointer target type",
4173 get_spelling (errtype), funname, parmnum);
4174 /* If this is not a case of ignoring a mismatch in signedness,
4176 else if (TYPE_MAIN_VARIANT (ttl) == void_type_node
4177 || TYPE_MAIN_VARIANT (ttr) == void_type_node
4178 || comp_target_types (type, rhstype))
4180 /* If there is a mismatch, do warn. */
4182 warn_for_assignment ("pointer targets in %s differ in signedness",
4183 get_spelling (errtype), funname, parmnum);
4185 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4186 && TREE_CODE (ttr) == FUNCTION_TYPE)
4188 /* Because const and volatile on functions are restrictions
4189 that say the function will not do certain things,
4190 it is okay to use a const or volatile function
4191 where an ordinary one is wanted, but not vice-versa. */
4192 if (TYPE_READONLY (ttl) && ! TYPE_READONLY (ttr))
4193 warn_for_assignment ("%s makes `const *' function pointer from non-const",
4194 get_spelling (errtype), funname, parmnum);
4195 if (TYPE_VOLATILE (ttl) && ! TYPE_VOLATILE (ttr))
4196 warn_for_assignment ("%s makes `volatile *' function pointer from non-volatile",
4197 get_spelling (errtype), funname, parmnum);
4201 warn_for_assignment ("%s from incompatible pointer type",
4202 get_spelling (errtype), funname, parmnum);
4203 return convert (type, rhs);
4205 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4207 /* An explicit constant 0 can convert to a pointer,
4208 or one that results from arithmetic, even including
4209 a cast to integer type. */
4210 if (! (TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
4212 ! (TREE_CODE (rhs) == NOP_EXPR
4213 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
4214 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
4215 && integer_zerop (TREE_OPERAND (rhs, 0))))
4217 warn_for_assignment ("%s makes pointer from integer without a cast",
4218 get_spelling (errtype), funname, parmnum);
4219 return convert (type, rhs);
4221 return null_pointer_node;
4223 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4225 warn_for_assignment ("%s makes integer from pointer without a cast",
4226 get_spelling (errtype), funname, parmnum);
4227 return convert (type, rhs);
4234 tree selector = maybe_building_objc_message_expr ();
4236 if (selector && parmnum > 2)
4237 error ("incompatible type for argument %d of `%s'",
4238 parmnum - 2, IDENTIFIER_POINTER (selector));
4240 error ("incompatible type for argument %d of `%s'",
4241 parmnum, IDENTIFIER_POINTER (funname));
4244 error ("incompatible type for argument %d of indirect function call",
4248 error ("incompatible types in %s", get_spelling (errtype));
4250 return error_mark_node;
4253 /* Print a warning using MSG.
4254 It gets OPNAME as its one parameter.
4255 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4256 FUNCTION and ARGNUM are handled specially if we are building an
4257 Objective-C selector. */
4260 warn_for_assignment (msg, opname, function, argnum)
4266 static char argstring[] = "passing arg %d of `%s'";
4267 static char argnofun[] = "passing arg %d";
4271 tree selector = maybe_building_objc_message_expr ();
4273 if (selector && argnum > 2)
4275 function = selector;
4280 /* Function name is known; supply it. */
4281 opname = (char *) alloca (IDENTIFIER_LENGTH (function)
4282 + sizeof (argstring) + 25 /*%d*/ + 1);
4283 sprintf (opname, argstring, argnum, IDENTIFIER_POINTER (function));
4287 /* Function name unknown (call through ptr); just give arg number. */
4288 opname = (char *) alloca (sizeof (argnofun) + 25 /*%d*/ + 1);
4289 sprintf (opname, argnofun, argnum);
4292 pedwarn (msg, opname);
4295 /* Return nonzero if VALUE is a valid constant-valued expression
4296 for use in initializing a static variable; one that can be an
4297 element of a "constant" initializer.
4299 Return null_pointer_node if the value is absolute;
4300 if it is relocatable, return the variable that determines the relocation.
4301 We assume that VALUE has been folded as much as possible;
4302 therefore, we do not need to check for such things as
4303 arithmetic-combinations of integers. */
4306 initializer_constant_valid_p (value, endtype)
4310 switch (TREE_CODE (value))
4313 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
4314 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE)
4315 && TREE_CONSTANT (value)
4316 && CONSTRUCTOR_ELTS (value))
4318 initializer_constant_valid_p (TREE_VALUE (CONSTRUCTOR_ELTS (value)),
4321 return TREE_STATIC (value) ? null_pointer_node : 0;
4327 return null_pointer_node;
4330 return TREE_OPERAND (value, 0);
4332 case NON_LVALUE_EXPR:
4333 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4337 /* Allow conversions between pointer types. */
4338 if (TREE_CODE (TREE_TYPE (value)) == POINTER_TYPE
4339 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == POINTER_TYPE)
4340 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4342 /* Allow conversions between real types. */
4343 if (TREE_CODE (TREE_TYPE (value)) == REAL_TYPE
4344 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == REAL_TYPE)
4345 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4347 /* Allow length-preserving conversions between integer types. */
4348 if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
4349 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE
4350 && (TYPE_PRECISION (TREE_TYPE (value))
4351 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
4352 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4354 /* Allow conversions between other integer types only if
4356 if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
4357 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE)
4359 tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0),
4361 if (inner == null_pointer_node)
4362 return null_pointer_node;
4366 /* Allow (int) &foo provided int is as wide as a pointer. */
4367 if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
4368 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == POINTER_TYPE
4369 && (TYPE_PRECISION (TREE_TYPE (value))
4370 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
4371 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
4374 /* Likewise conversions from int to pointers. */
4375 if (TREE_CODE (TREE_TYPE (value)) == POINTER_TYPE
4376 && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE
4377 && (TYPE_PRECISION (TREE_TYPE (value))
4378 <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
4379 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
4382 /* Allow conversions to union types if the value inside is okay. */
4383 if (TREE_CODE (TREE_TYPE (value)) == UNION_TYPE)
4384 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
4389 if (TREE_CODE (endtype) == INTEGER_TYPE
4390 && TYPE_PRECISION (endtype) < POINTER_SIZE)
4393 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
4395 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
4397 /* If either term is absolute, use the other terms relocation. */
4398 if (valid0 == null_pointer_node)
4400 if (valid1 == null_pointer_node)
4406 if (TREE_CODE (endtype) == INTEGER_TYPE
4407 && TYPE_PRECISION (endtype) < POINTER_SIZE)
4410 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
4412 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
4414 /* Win if second argument is absolute. */
4415 if (valid1 == null_pointer_node)
4417 /* Win if both arguments have the same relocation.
4418 Then the value is absolute. */
4419 if (valid0 == valid1)
4420 return null_pointer_node;
4428 /* If VALUE is a compound expr all of whose expressions are constant, then
4429 return its value. Otherwise, return error_mark_node.
4431 This is for handling COMPOUND_EXPRs as initializer elements
4432 which is allowed with a warning when -pedantic is specified. */
4435 valid_compound_expr_initializer (value, endtype)
4439 if (TREE_CODE (value) == COMPOUND_EXPR)
4441 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4443 return error_mark_node;
4444 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4447 else if (! TREE_CONSTANT (value)
4448 && ! initializer_constant_valid_p (value, endtype))
4449 return error_mark_node;
4454 /* Perform appropriate conversions on the initial value of a variable,
4455 store it in the declaration DECL,
4456 and print any error messages that are appropriate.
4457 If the init is invalid, store an ERROR_MARK. */
4460 store_init_value (decl, init)
4463 register tree value, type;
4465 /* If variable's type was invalidly declared, just ignore it. */
4467 type = TREE_TYPE (decl);
4468 if (TREE_CODE (type) == ERROR_MARK)
4471 /* Digest the specified initializer into an expression. */
4473 value = digest_init (type, init, TREE_STATIC (decl),
4474 TREE_STATIC (decl) || pedantic);
4476 /* Store the expression if valid; else report error. */
4479 /* Note that this is the only place we can detect the error
4480 in a case such as struct foo bar = (struct foo) { x, y };
4481 where there is one initial value which is a constructor expression. */
4482 if (value == error_mark_node)
4484 else if (TREE_STATIC (decl) && ! TREE_CONSTANT (value))
4486 error ("initializer for static variable is not constant");
4487 value = error_mark_node;
4489 else if (TREE_STATIC (decl)
4490 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
4492 error ("initializer for static variable uses complicated arithmetic");
4493 value = error_mark_node;
4497 if (pedantic && TREE_CODE (value) == CONSTRUCTOR)
4499 if (! TREE_CONSTANT (value))
4500 pedwarn ("aggregate initializer is not constant");
4501 else if (! TREE_STATIC (value))
4502 pedwarn ("aggregate initializer uses complicated arithmetic");
4507 DECL_INITIAL (decl) = value;
4509 /* ANSI wants warnings about out-of-range constant initializers. */
4510 STRIP_TYPE_NOPS (value);
4511 constant_expression_warning (value);
4514 /* Methods for storing and printing names for error messages. */
4516 /* Implement a spelling stack that allows components of a name to be pushed
4517 and popped. Each element on the stack is this structure. */
4529 #define SPELLING_STRING 1
4530 #define SPELLING_MEMBER 2
4531 #define SPELLING_BOUNDS 3
4533 static struct spelling *spelling; /* Next stack element (unused). */
4534 static struct spelling *spelling_base; /* Spelling stack base. */
4535 static int spelling_size; /* Size of the spelling stack. */
4537 /* Macros to save and restore the spelling stack around push_... functions.
4538 Alternative to SAVE_SPELLING_STACK. */
4540 #define SPELLING_DEPTH() (spelling - spelling_base)
4541 #define RESTORE_SPELLING_DEPTH(depth) (spelling = spelling_base + depth)
4543 /* Save and restore the spelling stack around arbitrary C code. */
4545 #define SAVE_SPELLING_DEPTH(code) \
4547 int __depth = SPELLING_DEPTH (); \
4549 RESTORE_SPELLING_DEPTH (__depth); \
4552 /* Push an element on the spelling stack with type KIND and assign VALUE
4555 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4557 int depth = SPELLING_DEPTH (); \
4559 if (depth >= spelling_size) \
4561 spelling_size += 10; \
4562 if (spelling_base == 0) \
4564 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4567 = (struct spelling *) xrealloc (spelling_base, \
4568 spelling_size * sizeof (struct spelling)); \
4569 RESTORE_SPELLING_DEPTH (depth); \
4572 spelling->kind = (KIND); \
4573 spelling->MEMBER = (VALUE); \
4577 /* Push STRING on the stack. Printed literally. */
4580 push_string (string)
4583 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4586 /* Push a member name on the stack. Printed as '.' STRING. */
4589 push_member_name (decl)
4594 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4595 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4598 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4601 push_array_bounds (bounds)
4604 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4607 /* Compute the maximum size in bytes of the printed spelling. */
4612 register int size = 0;
4613 register struct spelling *p;
4615 for (p = spelling_base; p < spelling; p++)
4617 if (p->kind == SPELLING_BOUNDS)
4620 size += strlen (p->u.s) + 1;
4626 /* Print the spelling to BUFFER and return it. */
4629 print_spelling (buffer)
4630 register char *buffer;
4632 register char *d = buffer;
4634 register struct spelling *p;
4636 for (p = spelling_base; p < spelling; p++)
4637 if (p->kind == SPELLING_BOUNDS)
4639 sprintf (d, "[%d]", p->u.i);
4644 if (p->kind == SPELLING_MEMBER)
4646 for (s = p->u.s; *d = *s++; d++)
4653 /* Provide a means to pass component names derived from the spelling stack. */
4655 char initialization_message;
4657 /* Interpret the spelling of the given ERRTYPE message. */
4660 get_spelling (errtype)
4663 static char *buffer;
4664 static int size = -1;
4666 if (errtype == &initialization_message)
4668 /* Avoid counting chars */
4669 static char message[] = "initialization of `%s'";
4670 register int needed = sizeof (message) + spelling_length () + 1;
4674 buffer = (char *) xmalloc (size = needed);
4676 buffer = (char *) xrealloc (buffer, size = needed);
4678 temp = (char *) alloca (needed);
4679 sprintf (buffer, message, print_spelling (temp));
4686 /* Issue an error message for a bad initializer component.
4687 FORMAT describes the message. OFWHAT is the name for the component.
4688 LOCAL is a format string for formatting the insertion of the name
4691 If OFWHAT is null, the component name is stored on the spelling stack.
4692 If the component name is a null string, then LOCAL is omitted entirely. */
4695 error_init (format, local, ofwhat)
4696 char *format, *local, *ofwhat;
4701 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4702 buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2);
4705 sprintf (buffer, local, ofwhat);
4709 error (format, buffer);
4712 /* Issue a pedantic warning for a bad initializer component.
4713 FORMAT describes the message. OFWHAT is the name for the component.
4714 LOCAL is a format string for formatting the insertion of the name
4717 If OFWHAT is null, the component name is stored on the spelling stack.
4718 If the component name is a null string, then LOCAL is omitted entirely. */
4721 pedwarn_init (format, local, ofwhat)
4722 char *format, *local, *ofwhat;
4727 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4728 buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2);
4731 sprintf (buffer, local, ofwhat);
4735 pedwarn (format, buffer);
4738 /* Issue a warning for a bad initializer component.
4739 FORMAT describes the message. OFWHAT is the name for the component.
4740 LOCAL is a format string for formatting the insertion of the name
4743 If OFWHAT is null, the component name is stored on the spelling stack.
4744 If the component name is a null string, then LOCAL is omitted entirely. */
4747 warning_init (format, local, ofwhat)
4748 char *format, *local, *ofwhat;
4753 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4754 buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2);
4757 sprintf (buffer, local, ofwhat);
4761 warning (format, buffer);
4764 /* Digest the parser output INIT as an initializer for type TYPE.
4765 Return a C expression of type TYPE to represent the initial value.
4767 The arguments REQUIRE_CONSTANT and CONSTRUCTOR_CONSTANT request errors
4768 if non-constant initializers or elements are seen. CONSTRUCTOR_CONSTANT
4769 applies only to elements of constructors. */
4772 digest_init (type, init, require_constant, constructor_constant)
4774 int require_constant, constructor_constant;
4776 enum tree_code code = TREE_CODE (type);
4777 tree inside_init = init;
4779 if (init == error_mark_node)
4782 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4783 /* Do not use STRIP_NOPS here. We do not want an enumerator
4784 whose value is 0 to count as a null pointer constant. */
4785 if (TREE_CODE (init) == NON_LVALUE_EXPR)
4786 inside_init = TREE_OPERAND (init, 0);
4788 /* Initialization of an array of chars from a string constant
4789 optionally enclosed in braces. */
4791 if (code == ARRAY_TYPE)
4793 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4794 if ((typ1 == char_type_node
4795 || typ1 == signed_char_type_node
4796 || typ1 == unsigned_char_type_node
4797 || typ1 == unsigned_wchar_type_node
4798 || typ1 == signed_wchar_type_node)
4799 && ((inside_init && TREE_CODE (inside_init) == STRING_CST)))
4801 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4802 TYPE_MAIN_VARIANT (type)))
4805 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4807 && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node))
4809 error_init ("char-array%s initialized from wide string",
4811 return error_mark_node;
4813 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4815 && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node))
4817 error_init ("int-array%s initialized from non-wide string",
4819 return error_mark_node;
4822 TREE_TYPE (inside_init) = type;
4823 if (TYPE_DOMAIN (type) != 0
4824 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
4826 register int size = TREE_INT_CST_LOW (TYPE_SIZE (type));
4827 size = (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
4828 /* Subtract 1 (or sizeof (wchar_t))
4829 because it's ok to ignore the terminating null char
4830 that is counted in the length of the constant. */
4831 if (size < TREE_STRING_LENGTH (inside_init)
4832 - (TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node)
4833 ? TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT
4836 "initializer-string for array of chars%s is too long",
4843 /* Any type can be initialized
4844 from an expression of the same type, optionally with braces. */
4846 if (inside_init && TREE_TYPE (inside_init) != 0
4847 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4848 TYPE_MAIN_VARIANT (type))
4849 || (code == ARRAY_TYPE
4850 && comptypes (TREE_TYPE (inside_init), type))
4851 || (code == POINTER_TYPE
4852 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4853 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE)
4854 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4855 TREE_TYPE (type)))))
4857 if (code == POINTER_TYPE
4858 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4859 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE))
4860 inside_init = default_conversion (inside_init);
4861 else if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4862 && TREE_CODE (inside_init) != CONSTRUCTOR)
4864 error_init ("array%s initialized from non-constant array expression",
4866 return error_mark_node;
4869 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4870 inside_init = decl_constant_value (inside_init);
4872 /* Compound expressions can only occur here if -pedantic or
4873 -pedantic-errors is specified. In the later case, we always want
4874 an error. In the former case, we simply want a warning. */
4875 if (require_constant && pedantic
4876 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4879 = valid_compound_expr_initializer (inside_init,
4880 TREE_TYPE (inside_init));
4881 if (inside_init == error_mark_node)
4882 error_init ("initializer element%s is not constant",
4885 pedwarn_init ("initializer element%s is not constant",
4887 if (flag_pedantic_errors)
4888 inside_init = error_mark_node;
4890 else if (require_constant && ! TREE_CONSTANT (inside_init))
4892 error_init ("initializer element%s is not constant",
4894 inside_init = error_mark_node;
4896 else if (require_constant
4897 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4899 error_init ("initializer element%s is not computable at load time",
4901 inside_init = error_mark_node;
4907 /* Handle scalar types, including conversions. */
4909 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4910 || code == ENUMERAL_TYPE || code == COMPLEX_TYPE)
4912 /* Note that convert_for_assignment calls default_conversion
4913 for arrays and functions. We must not call it in the
4914 case where inside_init is a null pointer constant. */
4916 = convert_for_assignment (type, init, "initialization",
4917 NULL_TREE, NULL_TREE, 0);
4919 if (require_constant && ! TREE_CONSTANT (inside_init))
4921 error_init ("initializer element%s is not constant",
4923 inside_init = error_mark_node;
4925 else if (require_constant
4926 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4928 error_init ("initializer element%s is not computable at load time",
4930 inside_init = error_mark_node;
4936 /* Come here only for records and arrays. */
4938 if (TYPE_SIZE (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4940 error_init ("variable-sized object%s may not be initialized",
4942 return error_mark_node;
4945 /* Traditionally, you can write struct foo x = 0;
4946 and it initializes the first element of x to 0. */
4947 if (flag_traditional)
4949 tree top = 0, prev = 0, otype = type;
4950 while (TREE_CODE (type) == RECORD_TYPE
4951 || TREE_CODE (type) == ARRAY_TYPE
4952 || TREE_CODE (type) == QUAL_UNION_TYPE
4953 || TREE_CODE (type) == UNION_TYPE)
4955 tree temp = build (CONSTRUCTOR, type, NULL_TREE, NULL_TREE);
4959 TREE_OPERAND (prev, 1) = build_tree_list (NULL_TREE, temp);
4961 if (TREE_CODE (type) == ARRAY_TYPE)
4962 type = TREE_TYPE (type);
4963 else if (TYPE_FIELDS (type))
4964 type = TREE_TYPE (TYPE_FIELDS (type));
4967 error_init ("invalid initializer%s", " for `%s'", NULL);
4968 return error_mark_node;
4974 TREE_OPERAND (prev, 1)
4975 = build_tree_list (NULL_TREE,
4976 digest_init (type, init, require_constant,
4977 constructor_constant));
4981 return error_mark_node;
4983 error_init ("invalid initializer%s", " for `%s'", NULL);
4984 return error_mark_node;
4987 /* Handle initializers that use braces. */
4989 /* Type of object we are accumulating a constructor for.
4990 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4991 static tree constructor_type;
4993 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4995 static tree constructor_fields;
4997 /* For an ARRAY_TYPE, this is the specified index
4998 at which to store the next element we get.
4999 This is a special INTEGER_CST node that we modify in place. */
5000 static tree constructor_index;
5002 /* For an ARRAY_TYPE, this is the end index of the range
5003 to initialize with the next element, or NULL in the ordinary case
5004 where the element is used just once. */
5005 static tree constructor_range_end;
5007 /* For an ARRAY_TYPE, this is the maximum index. */
5008 static tree constructor_max_index;
5010 /* For a RECORD_TYPE, this is the first field not yet written out. */
5011 static tree constructor_unfilled_fields;
5013 /* For an ARRAY_TYPE, this is the index of the first element
5014 not yet written out.
5015 This is a special INTEGER_CST node that we modify in place. */
5016 static tree constructor_unfilled_index;
5018 /* In a RECORD_TYPE, the byte index of the next consecutive field.
5019 This is so we can generate gaps between fields, when appropriate.
5020 This is a special INTEGER_CST node that we modify in place. */
5021 static tree constructor_bit_index;
5023 /* If we are saving up the elements rather than allocating them,
5024 this is the list of elements so far (in reverse order,
5025 most recent first). */
5026 static tree constructor_elements;
5028 /* 1 if so far this constructor's elements are all compile-time constants. */
5029 static int constructor_constant;
5031 /* 1 if so far this constructor's elements are all valid address constants. */
5032 static int constructor_simple;
5034 /* 1 if this constructor is erroneous so far. */
5035 static int constructor_erroneous;
5037 /* 1 if have called defer_addressed_constants. */
5038 static int constructor_subconstants_deferred;
5040 /* List of pending elements at this constructor level.
5041 These are elements encountered out of order
5042 which belong at places we haven't reached yet in actually
5043 writing the output. */
5044 static tree constructor_pending_elts;
5046 /* The SPELLING_DEPTH of this constructor. */
5047 static int constructor_depth;
5049 /* 0 if implicitly pushing constructor levels is allowed. */
5050 int constructor_no_implicit = 0; /* 0 for C; 1 for some other languages. */
5052 /* 1 if this constructor level was entered implicitly. */
5053 static int constructor_implicit;
5055 static int require_constant_value;
5056 static int require_constant_elements;
5058 /* 1 if it is ok to output this constructor as we read it.
5059 0 means must accumulate a CONSTRUCTOR expression. */
5060 static int constructor_incremental;
5062 /* DECL node for which an initializer is being read.
5063 0 means we are reading a constructor expression
5064 such as (struct foo) {...}. */
5065 static tree constructor_decl;
5067 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
5068 static char *constructor_asmspec;
5070 /* Nonzero if this is an initializer for a top-level decl. */
5071 static int constructor_top_level;
5073 /* When we finish reading a constructor expression
5074 (constructor_decl is 0), the CONSTRUCTOR goes here. */
5075 static tree constructor_result;
5077 /* This stack has a level for each implicit or explicit level of
5078 structuring in the initializer, including the outermost one. It
5079 saves the values of most of the variables above. */
5081 struct constructor_stack
5083 struct constructor_stack *next;
5089 tree unfilled_index;
5090 tree unfilled_fields;
5096 /* If nonzero, this value should replace the entire
5097 constructor at this level. */
5098 tree replacement_value;
5107 struct constructor_stack *constructor_stack;
5109 /* This stack records separate initializers that are nested.
5110 Nested initializers can't happen in ANSI C, but GNU C allows them
5111 in cases like { ... (struct foo) { ... } ... }. */
5113 struct initializer_stack
5115 struct initializer_stack *next;
5118 struct constructor_stack *constructor_stack;
5120 struct spelling *spelling;
5121 struct spelling *spelling_base;
5125 char require_constant_value;
5126 char require_constant_elements;
5130 struct initializer_stack *initializer_stack;
5132 /* Prepare to parse and output the initializer for variable DECL. */
5135 start_init (decl, asmspec_tree, top_level)
5141 struct initializer_stack *p
5142 = (struct initializer_stack *) xmalloc (sizeof (struct initializer_stack));
5146 asmspec = TREE_STRING_POINTER (asmspec_tree);
5148 p->decl = constructor_decl;
5149 p->asmspec = constructor_asmspec;
5150 p->incremental = constructor_incremental;
5151 p->require_constant_value = require_constant_value;
5152 p->require_constant_elements = require_constant_elements;
5153 p->constructor_stack = constructor_stack;
5154 p->elements = constructor_elements;
5155 p->spelling = spelling;
5156 p->spelling_base = spelling_base;
5157 p->spelling_size = spelling_size;
5158 p->deferred = constructor_subconstants_deferred;
5159 p->top_level = constructor_top_level;
5160 p->next = initializer_stack;
5161 initializer_stack = p;
5163 constructor_decl = decl;
5164 constructor_incremental = top_level;
5165 constructor_asmspec = asmspec;
5166 constructor_subconstants_deferred = 0;
5167 constructor_top_level = top_level;
5171 require_constant_value = TREE_STATIC (decl);
5172 require_constant_elements
5173 = ((TREE_STATIC (decl) || pedantic)
5174 /* For a scalar, you can always use any value to initialize,
5175 even within braces. */
5176 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
5177 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
5178 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
5179 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
5180 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
5181 constructor_incremental |= TREE_STATIC (decl);
5185 require_constant_value = 0;
5186 require_constant_elements = 0;
5187 locus = "(anonymous)";
5190 constructor_stack = 0;
5192 missing_braces_mentioned = 0;
5196 RESTORE_SPELLING_DEPTH (0);
5199 push_string (locus);
5205 struct initializer_stack *p = initializer_stack;
5207 /* Output subconstants (string constants, usually)
5208 that were referenced within this initializer and saved up.
5209 Must do this if and only if we called defer_addressed_constants. */
5210 if (constructor_subconstants_deferred)
5211 output_deferred_addressed_constants ();
5213 /* Free the whole constructor stack of this initializer. */
5214 while (constructor_stack)
5216 struct constructor_stack *q = constructor_stack;
5217 constructor_stack = q->next;
5221 /* Pop back to the data of the outer initializer (if any). */
5222 constructor_decl = p->decl;
5223 constructor_asmspec = p->asmspec;
5224 constructor_incremental = p->incremental;
5225 require_constant_value = p->require_constant_value;
5226 require_constant_elements = p->require_constant_elements;
5227 constructor_stack = p->constructor_stack;
5228 constructor_elements = p->elements;
5229 spelling = p->spelling;
5230 spelling_base = p->spelling_base;
5231 spelling_size = p->spelling_size;
5232 constructor_subconstants_deferred = p->deferred;
5233 constructor_top_level = p->top_level;
5234 initializer_stack = p->next;
5238 /* Call here when we see the initializer is surrounded by braces.
5239 This is instead of a call to push_init_level;
5240 it is matched by a call to pop_init_level.
5242 TYPE is the type to initialize, for a constructor expression.
5243 For an initializer for a decl, TYPE is zero. */
5246 really_start_incremental_init (type)
5249 struct constructor_stack *p
5250 = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5253 type = TREE_TYPE (constructor_decl);
5255 /* Turn off constructor_incremental if type is a struct with bitfields.
5256 Do this before the first push, so that the corrected value
5257 is available in finish_init. */
5258 check_init_type_bitfields (type);
5260 p->type = constructor_type;
5261 p->fields = constructor_fields;
5262 p->index = constructor_index;
5263 p->range_end = constructor_range_end;
5264 p->max_index = constructor_max_index;
5265 p->unfilled_index = constructor_unfilled_index;
5266 p->unfilled_fields = constructor_unfilled_fields;
5267 p->bit_index = constructor_bit_index;
5268 p->elements = constructor_elements;
5269 p->constant = constructor_constant;
5270 p->simple = constructor_simple;
5271 p->erroneous = constructor_erroneous;
5272 p->pending_elts = constructor_pending_elts;
5273 p->depth = constructor_depth;
5274 p->replacement_value = 0;
5276 p->incremental = constructor_incremental;
5279 constructor_stack = p;
5281 constructor_constant = 1;
5282 constructor_simple = 1;
5283 constructor_depth = SPELLING_DEPTH ();
5284 constructor_elements = 0;
5285 constructor_pending_elts = 0;
5286 constructor_type = type;
5288 if (TREE_CODE (constructor_type) == RECORD_TYPE
5289 || TREE_CODE (constructor_type) == UNION_TYPE)
5291 constructor_fields = TYPE_FIELDS (constructor_type);
5292 /* Skip any nameless bit fields at the beginning. */
5293 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5294 && DECL_NAME (constructor_fields) == 0)
5295 constructor_fields = TREE_CHAIN (constructor_fields);
5296 constructor_unfilled_fields = constructor_fields;
5297 constructor_bit_index = copy_node (integer_zero_node);
5299 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5301 constructor_range_end = 0;
5302 if (TYPE_DOMAIN (constructor_type))
5304 constructor_max_index
5305 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5307 = copy_node (TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5310 constructor_index = copy_node (integer_zero_node);
5311 constructor_unfilled_index = copy_node (constructor_index);
5315 /* Handle the case of int x = {5}; */
5316 constructor_fields = constructor_type;
5317 constructor_unfilled_fields = constructor_type;
5320 if (constructor_incremental)
5322 int momentary = suspend_momentary ();
5323 push_obstacks_nochange ();
5324 if (TREE_PERMANENT (constructor_decl))
5325 end_temporary_allocation ();
5326 make_decl_rtl (constructor_decl, constructor_asmspec,
5327 constructor_top_level);
5328 assemble_variable (constructor_decl, constructor_top_level, 0, 1);
5330 resume_momentary (momentary);
5333 if (constructor_incremental)
5335 defer_addressed_constants ();
5336 constructor_subconstants_deferred = 1;
5340 /* Push down into a subobject, for initialization.
5341 If this is for an explicit set of braces, IMPLICIT is 0.
5342 If it is because the next element belongs at a lower level,
5346 push_init_level (implicit)
5349 struct constructor_stack *p;
5351 /* If we've exhausted any levels that didn't have braces,
5353 while (constructor_stack->implicit)
5355 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5356 || TREE_CODE (constructor_type) == UNION_TYPE)
5357 && constructor_fields == 0)
5358 process_init_element (pop_init_level (1));
5359 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5360 && tree_int_cst_lt (constructor_max_index, constructor_index))
5361 process_init_element (pop_init_level (1));
5366 /* Structure elements may require alignment. Do this now if necessary
5367 for the subaggregate, and if it comes next in sequence. Don't do
5368 this for subaggregates that will go on the pending list. */
5369 if (constructor_incremental && constructor_type != 0
5370 && TREE_CODE (constructor_type) == RECORD_TYPE && constructor_fields
5371 && constructor_fields == constructor_unfilled_fields)
5373 /* Advance to offset of this element. */
5374 if (! tree_int_cst_equal (constructor_bit_index,
5375 DECL_FIELD_BITPOS (constructor_fields)))
5377 int next = (TREE_INT_CST_LOW
5378 (DECL_FIELD_BITPOS (constructor_fields))
5380 int here = (TREE_INT_CST_LOW (constructor_bit_index)
5383 assemble_zeros (next - here);
5385 /* Indicate that we have now filled the structure up to the current
5387 constructor_unfilled_fields = constructor_fields;
5390 p = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5391 p->type = constructor_type;
5392 p->fields = constructor_fields;
5393 p->index = constructor_index;
5394 p->range_end = constructor_range_end;
5395 p->max_index = constructor_max_index;
5396 p->unfilled_index = constructor_unfilled_index;
5397 p->unfilled_fields = constructor_unfilled_fields;
5398 p->bit_index = constructor_bit_index;
5399 p->elements = constructor_elements;
5400 p->constant = constructor_constant;
5401 p->simple = constructor_simple;
5402 p->erroneous = constructor_erroneous;
5403 p->pending_elts = constructor_pending_elts;
5404 p->depth = constructor_depth;
5405 p->replacement_value = 0;
5406 p->implicit = implicit;
5407 p->incremental = constructor_incremental;
5409 p->next = constructor_stack;
5410 constructor_stack = p;
5412 constructor_constant = 1;
5413 constructor_simple = 1;
5414 constructor_depth = SPELLING_DEPTH ();
5415 constructor_elements = 0;
5416 constructor_pending_elts = 0;
5418 /* Don't die if an entire brace-pair level is superfluous
5419 in the containing level. */
5420 if (constructor_type == 0)
5422 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5423 || TREE_CODE (constructor_type) == UNION_TYPE)
5425 /* Don't die if there are extra init elts at the end. */
5426 if (constructor_fields == 0)
5427 constructor_type = 0;
5430 constructor_type = TREE_TYPE (constructor_fields);
5431 push_member_name (constructor_fields);
5432 constructor_depth++;
5433 if (constructor_fields != constructor_unfilled_fields)
5434 constructor_incremental = 0;
5437 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5439 constructor_type = TREE_TYPE (constructor_type);
5440 push_array_bounds (TREE_INT_CST_LOW (constructor_index));
5441 constructor_depth++;
5442 if (! tree_int_cst_equal (constructor_index, constructor_unfilled_index)
5443 || constructor_range_end != 0)
5444 constructor_incremental = 0;
5447 if (constructor_type == 0)
5449 error_init ("extra brace group at end of initializer%s",
5451 constructor_fields = 0;
5452 constructor_unfilled_fields = 0;
5456 /* Turn off constructor_incremental if type is a struct with bitfields. */
5457 check_init_type_bitfields (constructor_type);
5459 if (implicit && warn_missing_braces && !missing_braces_mentioned)
5461 missing_braces_mentioned = 1;
5462 warning_init ("missing braces around initializer%s", " for `%s'", NULL);
5465 if (TREE_CODE (constructor_type) == RECORD_TYPE
5466 || TREE_CODE (constructor_type) == UNION_TYPE)
5468 constructor_fields = TYPE_FIELDS (constructor_type);
5469 /* Skip any nameless bit fields at the beginning. */
5470 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5471 && DECL_NAME (constructor_fields) == 0)
5472 constructor_fields = TREE_CHAIN (constructor_fields);
5473 constructor_unfilled_fields = constructor_fields;
5474 constructor_bit_index = copy_node (integer_zero_node);
5476 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5478 constructor_range_end = 0;
5479 if (TYPE_DOMAIN (constructor_type))
5481 constructor_max_index
5482 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5484 = copy_node (TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5487 constructor_index = copy_node (integer_zero_node);
5488 constructor_unfilled_index = copy_node (constructor_index);
5492 warning_init ("braces around scalar initializer%s", " for `%s'", NULL);
5493 constructor_fields = constructor_type;
5494 constructor_unfilled_fields = constructor_type;
5498 /* Don't read a struct incrementally if it has any bitfields,
5499 because the incremental reading code doesn't know how to
5500 handle bitfields yet. */
5503 check_init_type_bitfields (type)
5506 if (TREE_CODE (type) == RECORD_TYPE)
5509 for (tail = TYPE_FIELDS (type); tail;
5510 tail = TREE_CHAIN (tail))
5512 if (DECL_C_BIT_FIELD (tail)
5513 /* This catches cases like `int foo : 8;'. */
5514 || DECL_MODE (tail) != TYPE_MODE (TREE_TYPE (tail)))
5516 constructor_incremental = 0;
5520 check_init_type_bitfields (TREE_TYPE (tail));
5524 else if (TREE_CODE (type) == ARRAY_TYPE)
5525 check_init_type_bitfields (TREE_TYPE (type));
5528 /* At the end of an implicit or explicit brace level,
5529 finish up that level of constructor.
5530 If we were outputting the elements as they are read, return 0
5531 from inner levels (process_init_element ignores that),
5532 but return error_mark_node from the outermost level
5533 (that's what we want to put in DECL_INITIAL).
5534 Otherwise, return a CONSTRUCTOR expression. */
5537 pop_init_level (implicit)
5540 struct constructor_stack *p;
5542 tree constructor = 0;
5546 /* When we come to an explicit close brace,
5547 pop any inner levels that didn't have explicit braces. */
5548 while (constructor_stack->implicit)
5549 process_init_element (pop_init_level (1));
5552 p = constructor_stack;
5554 if (constructor_type != 0)
5555 size = int_size_in_bytes (constructor_type);
5557 /* Now output all pending elements. */
5558 output_pending_init_elements (1);
5560 #if 0 /* c-parse.in warns about {}. */
5561 /* In ANSI, each brace level must have at least one element. */
5562 if (! implicit && pedantic
5563 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5564 ? integer_zerop (constructor_unfilled_index)
5565 : constructor_unfilled_fields == TYPE_FIELDS (constructor_type)))
5566 pedwarn_init ("empty braces in initializer%s", " for `%s'", NULL);
5569 /* Pad out the end of the structure. */
5571 if (p->replacement_value)
5573 /* If this closes a superfluous brace pair,
5574 just pass out the element between them. */
5575 constructor = p->replacement_value;
5576 /* If this is the top level thing within the initializer,
5577 and it's for a variable, then since we already called
5578 assemble_variable, we must output the value now. */
5579 if (p->next == 0 && constructor_decl != 0
5580 && constructor_incremental)
5582 constructor = digest_init (constructor_type, constructor,
5583 require_constant_value,
5584 require_constant_elements);
5586 /* If initializing an array of unknown size,
5587 determine the size now. */
5588 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5589 && TYPE_DOMAIN (constructor_type) == 0)
5594 push_obstacks_nochange ();
5595 if (TREE_PERMANENT (constructor_type))
5596 end_temporary_allocation ();
5598 momentary_p = suspend_momentary ();
5600 /* We shouldn't have an incomplete array type within
5602 if (constructor_stack->next)
5606 = complete_array_type (constructor_type,
5611 size = int_size_in_bytes (constructor_type);
5612 resume_momentary (momentary_p);
5616 output_constant (constructor, size);
5619 else if (constructor_type == 0)
5621 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5622 && TREE_CODE (constructor_type) != UNION_TYPE
5623 && TREE_CODE (constructor_type) != ARRAY_TYPE
5624 && ! constructor_incremental)
5626 /* A nonincremental scalar initializer--just return
5627 the element, after verifying there is just one. */
5628 if (constructor_elements == 0)
5630 error_init ("empty scalar initializer%s",
5632 constructor = error_mark_node;
5634 else if (TREE_CHAIN (constructor_elements) != 0)
5636 error_init ("extra elements in scalar initializer%s",
5638 constructor = TREE_VALUE (constructor_elements);
5641 constructor = TREE_VALUE (constructor_elements);
5643 else if (! constructor_incremental)
5645 if (constructor_erroneous)
5646 constructor = error_mark_node;
5649 int momentary = suspend_momentary ();
5651 constructor = build (CONSTRUCTOR, constructor_type, NULL_TREE,
5652 nreverse (constructor_elements));
5653 if (constructor_constant)
5654 TREE_CONSTANT (constructor) = 1;
5655 if (constructor_constant && constructor_simple)
5656 TREE_STATIC (constructor) = 1;
5658 resume_momentary (momentary);
5664 int momentary = suspend_momentary ();
5666 if (TREE_CODE (constructor_type) == RECORD_TYPE
5667 || TREE_CODE (constructor_type) == UNION_TYPE)
5669 /* Find the offset of the end of that field. */
5670 filled = size_binop (CEIL_DIV_EXPR,
5671 constructor_bit_index,
5672 size_int (BITS_PER_UNIT));
5674 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5676 /* If initializing an array of unknown size,
5677 determine the size now. */
5678 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5679 && TYPE_DOMAIN (constructor_type) == 0)
5682 = size_binop (MINUS_EXPR,
5683 constructor_unfilled_index,
5686 push_obstacks_nochange ();
5687 if (TREE_PERMANENT (constructor_type))
5688 end_temporary_allocation ();
5689 maxindex = copy_node (maxindex);
5690 TYPE_DOMAIN (constructor_type) = build_index_type (maxindex);
5691 TREE_TYPE (maxindex) = TYPE_DOMAIN (constructor_type);
5693 /* TYPE_MAX_VALUE is always one less than the number of elements
5694 in the array, because we start counting at zero. Therefore,
5695 warn only if the value is less than zero. */
5697 && (tree_int_cst_sgn (TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5699 error_with_decl (constructor_decl,
5700 "zero or negative array size `%s'");
5701 layout_type (constructor_type);
5702 size = int_size_in_bytes (constructor_type);
5706 filled = size_binop (MULT_EXPR, constructor_unfilled_index,
5707 size_in_bytes (TREE_TYPE (constructor_type)));
5713 assemble_zeros (size - TREE_INT_CST_LOW (filled));
5715 resume_momentary (momentary);
5719 constructor_type = p->type;
5720 constructor_fields = p->fields;
5721 constructor_index = p->index;
5722 constructor_range_end = p->range_end;
5723 constructor_max_index = p->max_index;
5724 constructor_unfilled_index = p->unfilled_index;
5725 constructor_unfilled_fields = p->unfilled_fields;
5726 constructor_bit_index = p->bit_index;
5727 constructor_elements = p->elements;
5728 constructor_constant = p->constant;
5729 constructor_simple = p->simple;
5730 constructor_erroneous = p->erroneous;
5731 constructor_pending_elts = p->pending_elts;
5732 constructor_depth = p->depth;
5733 constructor_incremental = p->incremental;
5734 RESTORE_SPELLING_DEPTH (constructor_depth);
5736 constructor_stack = p->next;
5739 if (constructor == 0)
5741 if (constructor_stack == 0)
5742 return error_mark_node;
5748 /* Within an array initializer, specify the next index to be initialized.
5749 FIRST is that index. If LAST is nonzero, then initialize a range
5750 of indices, running from FIRST through LAST. */
5753 set_init_index (first, last)
5756 while ((TREE_CODE (first) == NOP_EXPR
5757 || TREE_CODE (first) == CONVERT_EXPR
5758 || TREE_CODE (first) == NON_LVALUE_EXPR)
5759 && (TYPE_MODE (TREE_TYPE (first))
5760 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0)))))
5761 (first) = TREE_OPERAND (first, 0);
5763 while ((TREE_CODE (last) == NOP_EXPR
5764 || TREE_CODE (last) == CONVERT_EXPR
5765 || TREE_CODE (last) == NON_LVALUE_EXPR)
5766 && (TYPE_MODE (TREE_TYPE (last))
5767 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0)))))
5768 (last) = TREE_OPERAND (last, 0);
5770 if (TREE_CODE (first) != INTEGER_CST)
5771 error_init ("nonconstant array index in initializer%s", " for `%s'", NULL);
5772 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5773 error_init ("nonconstant array index in initializer%s", " for `%s'", NULL);
5774 else if (! constructor_unfilled_index)
5775 error_init ("array index in non-array initializer%s", " for `%s'", NULL);
5776 else if (tree_int_cst_lt (first, constructor_unfilled_index))
5777 error_init ("duplicate array index in initializer%s", " for `%s'", NULL);
5780 TREE_INT_CST_LOW (constructor_index)
5781 = TREE_INT_CST_LOW (first);
5782 TREE_INT_CST_HIGH (constructor_index)
5783 = TREE_INT_CST_HIGH (first);
5785 if (last != 0 && tree_int_cst_lt (last, first))
5786 error_init ("empty index range in initializer%s", " for `%s'", NULL);
5790 pedwarn ("ANSI C forbids specifying element to initialize");
5791 constructor_range_end = last;
5796 /* Within a struct initializer, specify the next field to be initialized. */
5799 set_init_label (fieldname)
5805 /* Don't die if an entire brace-pair level is superfluous
5806 in the containing level. */
5807 if (constructor_type == 0)
5810 for (tail = TYPE_FIELDS (constructor_type); tail;
5811 tail = TREE_CHAIN (tail))
5813 if (tail == constructor_unfilled_fields)
5815 if (DECL_NAME (tail) == fieldname)
5820 error ("unknown field `%s' specified in initializer",
5821 IDENTIFIER_POINTER (fieldname));
5823 error ("field `%s' already initialized",
5824 IDENTIFIER_POINTER (fieldname));
5827 constructor_fields = tail;
5829 pedwarn ("ANSI C forbids specifying structure member to initialize");
5833 /* "Output" the next constructor element.
5834 At top level, really output it to assembler code now.
5835 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5836 TYPE is the data type that the containing data type wants here.
5837 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5839 PENDING if non-nil means output pending elements that belong
5840 right after this element. (PENDING is normally 1;
5841 it is 0 while outputting pending elements, to avoid recursion.) */
5844 output_init_element (value, type, field, pending)
5845 tree value, type, field;
5850 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5851 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5852 && !(TREE_CODE (value) == STRING_CST
5853 && TREE_CODE (type) == ARRAY_TYPE
5854 && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE)
5855 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5856 TYPE_MAIN_VARIANT (type))))
5857 value = default_conversion (value);
5859 if (value == error_mark_node)
5860 constructor_erroneous = 1;
5861 else if (!TREE_CONSTANT (value))
5862 constructor_constant = 0;
5863 else if (initializer_constant_valid_p (value, TREE_TYPE (value)) == 0
5864 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5865 || TREE_CODE (constructor_type) == UNION_TYPE)
5866 && DECL_C_BIT_FIELD (field)
5867 && TREE_CODE (value) != INTEGER_CST))
5868 constructor_simple = 0;
5870 if (require_constant_value && ! TREE_CONSTANT (value))
5872 error_init ("initializer element%s is not constant",
5874 value = error_mark_node;
5876 else if (require_constant_elements
5877 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
5879 error_init ("initializer element%s is not computable at load time",
5881 value = error_mark_node;
5884 /* If this element duplicates one on constructor_pending_elts,
5885 print a message and ignore it. Don't do this when we're
5886 processing elements taken off constructor_pending_elts,
5887 because we'd always get spurious errors. */
5890 if (TREE_CODE (constructor_type) == RECORD_TYPE
5891 || TREE_CODE (constructor_type) == UNION_TYPE)
5893 if (purpose_member (field, constructor_pending_elts))
5895 error_init ("duplicate initializer%s", " for `%s'", NULL);
5899 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5902 for (tail = constructor_pending_elts; tail;
5903 tail = TREE_CHAIN (tail))
5904 if (TREE_PURPOSE (tail) != 0
5905 && TREE_CODE (TREE_PURPOSE (tail)) == INTEGER_CST
5906 && tree_int_cst_equal (TREE_PURPOSE (tail), constructor_index))
5911 error_init ("duplicate initializer%s", " for `%s'", NULL);
5917 /* If this element doesn't come next in sequence,
5918 put it on constructor_pending_elts. */
5919 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5920 && !tree_int_cst_equal (field, constructor_unfilled_index))
5923 /* The copy_node is needed in case field is actually
5924 constructor_index, which is modified in place. */
5925 constructor_pending_elts
5926 = tree_cons (copy_node (field),
5927 digest_init (type, value, require_constant_value,
5928 require_constant_elements),
5929 constructor_pending_elts);
5931 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5932 && field != constructor_unfilled_fields)
5934 /* We do this for records but not for unions. In a union,
5935 no matter which field is specified, it can be initialized
5936 right away since it starts at the beginning of the union. */
5938 constructor_pending_elts
5940 digest_init (type, value, require_constant_value,
5941 require_constant_elements),
5942 constructor_pending_elts);
5946 /* Otherwise, output this element either to
5947 constructor_elements or to the assembler file. */
5951 if (! constructor_incremental)
5953 if (field && TREE_CODE (field) == INTEGER_CST)
5954 field = copy_node (field);
5955 constructor_elements
5956 = tree_cons (field, digest_init (type, value,
5957 require_constant_value,
5958 require_constant_elements),
5959 constructor_elements);
5963 /* Structure elements may require alignment.
5964 Do this, if necessary. */
5965 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5967 /* Advance to offset of this element. */
5968 if (! tree_int_cst_equal (constructor_bit_index,
5969 DECL_FIELD_BITPOS (field)))
5971 int next = (TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field))
5973 int here = (TREE_INT_CST_LOW (constructor_bit_index)
5976 assemble_zeros (next - here);
5979 output_constant (digest_init (type, value,
5980 require_constant_value,
5981 require_constant_elements),
5982 int_size_in_bytes (type));
5984 /* For a record or union,
5985 keep track of end position of last field. */
5986 if (TREE_CODE (constructor_type) == RECORD_TYPE
5987 || TREE_CODE (constructor_type) == UNION_TYPE)
5989 tree temp = size_binop (PLUS_EXPR, DECL_FIELD_BITPOS (field),
5991 TREE_INT_CST_LOW (constructor_bit_index)
5992 = TREE_INT_CST_LOW (temp);
5993 TREE_INT_CST_HIGH (constructor_bit_index)
5994 = TREE_INT_CST_HIGH (temp);
5999 /* Advance the variable that indicates sequential elements output. */
6000 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6002 tree tem = size_binop (PLUS_EXPR, constructor_unfilled_index,
6004 TREE_INT_CST_LOW (constructor_unfilled_index)
6005 = TREE_INT_CST_LOW (tem);
6006 TREE_INT_CST_HIGH (constructor_unfilled_index)
6007 = TREE_INT_CST_HIGH (tem);
6009 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6010 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
6011 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6012 constructor_unfilled_fields = 0;
6014 /* Now output any pending elements which have become next. */
6016 output_pending_init_elements (0);
6020 /* Output any pending elements which have become next.
6021 As we output elements, constructor_unfilled_{fields,index}
6022 advances, which may cause other elements to become next;
6023 if so, they too are output.
6025 If ALL is 0, we return when there are
6026 no more pending elements to output now.
6028 If ALL is 1, we output space as necessary so that
6029 we can output all the pending elements. */
6032 output_pending_init_elements (all)
6040 /* Look thru the whole pending list.
6041 If we find an element that should be output now,
6042 output it. Otherwise, set NEXT to the element
6043 that comes first among those still pending. */
6046 for (tail = constructor_pending_elts; tail;
6047 tail = TREE_CHAIN (tail))
6049 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6051 if (tree_int_cst_equal (TREE_PURPOSE (tail),
6052 constructor_unfilled_index))
6054 output_init_element (TREE_VALUE (tail),
6055 TREE_TYPE (constructor_type),
6056 constructor_unfilled_index, 0);
6059 else if (tree_int_cst_lt (TREE_PURPOSE (tail),
6060 constructor_unfilled_index))
6063 || tree_int_cst_lt (TREE_PURPOSE (tail), next))
6064 next = TREE_PURPOSE (tail);
6066 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6067 || TREE_CODE (constructor_type) == UNION_TYPE)
6069 if (TREE_PURPOSE (tail) == constructor_unfilled_fields)
6071 output_init_element (TREE_VALUE (tail),
6072 TREE_TYPE (constructor_unfilled_fields),
6073 constructor_unfilled_fields,
6077 else if (constructor_unfilled_fields == 0
6078 || tree_int_cst_lt (DECL_FIELD_BITPOS (TREE_PURPOSE (tail)),
6079 DECL_FIELD_BITPOS (constructor_unfilled_fields)))
6082 || tree_int_cst_lt (DECL_FIELD_BITPOS (TREE_PURPOSE (tail)),
6083 DECL_FIELD_BITPOS (next)))
6084 next = TREE_PURPOSE (tail);
6088 /* Ordinarily return, but not if we want to output all
6089 and there are elements left. */
6090 if (! (all && next != 0))
6093 /* Generate space up to the position of NEXT. */
6094 if (constructor_incremental)
6097 tree nextpos_tree = size_int (0);
6099 if (TREE_CODE (constructor_type) == RECORD_TYPE
6100 || TREE_CODE (constructor_type) == UNION_TYPE)
6102 /* Find the last field written out, if any. */
6103 for (tail = TYPE_FIELDS (constructor_type); tail;
6104 tail = TREE_CHAIN (tail))
6105 if (TREE_CHAIN (tail) == constructor_unfilled_fields)
6109 /* Find the offset of the end of that field. */
6110 filled = size_binop (CEIL_DIV_EXPR,
6111 size_binop (PLUS_EXPR,
6112 DECL_FIELD_BITPOS (tail),
6114 size_int (BITS_PER_UNIT));
6116 filled = size_int (0);
6118 nextpos_tree = size_binop (CEIL_DIV_EXPR,
6119 DECL_FIELD_BITPOS (next),
6120 size_int (BITS_PER_UNIT));
6122 TREE_INT_CST_HIGH (constructor_bit_index)
6123 = TREE_INT_CST_HIGH (DECL_FIELD_BITPOS (next));
6124 TREE_INT_CST_LOW (constructor_bit_index)
6125 = TREE_INT_CST_LOW (DECL_FIELD_BITPOS (next));
6126 constructor_unfilled_fields = next;
6128 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6130 filled = size_binop (MULT_EXPR, constructor_unfilled_index,
6131 size_in_bytes (TREE_TYPE (constructor_type)));
6133 = size_binop (MULT_EXPR, next,
6134 size_in_bytes (TREE_TYPE (constructor_type)));
6135 TREE_INT_CST_LOW (constructor_unfilled_index)
6136 = TREE_INT_CST_LOW (next);
6137 TREE_INT_CST_HIGH (constructor_unfilled_index)
6138 = TREE_INT_CST_HIGH (next);
6145 int nextpos = TREE_INT_CST_LOW (nextpos_tree);
6147 assemble_zeros (nextpos - TREE_INT_CST_LOW (filled));
6152 /* If it's not incremental, just skip over the gap,
6153 so that after jumping to retry we will output the next
6154 successive element. */
6155 if (TREE_CODE (constructor_type) == RECORD_TYPE
6156 || TREE_CODE (constructor_type) == UNION_TYPE)
6157 constructor_unfilled_fields = next;
6158 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6160 TREE_INT_CST_LOW (constructor_unfilled_index)
6161 = TREE_INT_CST_LOW (next);
6162 TREE_INT_CST_HIGH (constructor_unfilled_index)
6163 = TREE_INT_CST_HIGH (next);
6170 /* Add one non-braced element to the current constructor level.
6171 This adjusts the current position within the constructor's type.
6172 This may also start or terminate implicit levels
6173 to handle a partly-braced initializer.
6175 Once this has found the correct level for the new element,
6176 it calls output_init_element.
6178 Note: if we are incrementally outputting this constructor,
6179 this function may be called with a null argument
6180 representing a sub-constructor that was already incrementally output.
6181 When that happens, we output nothing, but we do the bookkeeping
6182 to skip past that element of the current constructor. */
6185 process_init_element (value)
6188 tree orig_value = value;
6189 int string_flag = value != 0 && TREE_CODE (value) == STRING_CST;
6191 /* Handle superfluous braces around string cst as in
6192 char x[] = {"foo"}; */
6195 && TREE_CODE (constructor_type) == ARRAY_TYPE
6196 && TREE_CODE (TREE_TYPE (constructor_type)) == INTEGER_TYPE
6197 && integer_zerop (constructor_unfilled_index))
6199 constructor_stack->replacement_value = value;
6203 if (constructor_stack->replacement_value != 0)
6205 error_init ("excess elements in struct initializer%s",
6206 " after `%s'", NULL_PTR);
6210 /* Ignore elements of a brace group if it is entirely superfluous
6211 and has already been diagnosed. */
6212 if (constructor_type == 0)
6215 /* If we've exhausted any levels that didn't have braces,
6217 while (constructor_stack->implicit)
6219 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6220 || TREE_CODE (constructor_type) == UNION_TYPE)
6221 && constructor_fields == 0)
6222 process_init_element (pop_init_level (1));
6223 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6224 && tree_int_cst_lt (constructor_max_index, constructor_index))
6225 process_init_element (pop_init_level (1));
6232 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6235 enum tree_code fieldcode;
6237 if (constructor_fields == 0)
6239 pedwarn_init ("excess elements in struct initializer%s",
6240 " after `%s'", NULL_PTR);
6244 fieldtype = TREE_TYPE (constructor_fields);
6245 if (fieldtype != error_mark_node)
6246 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6247 fieldcode = TREE_CODE (fieldtype);
6249 /* Accept a string constant to initialize a subarray. */
6251 && fieldcode == ARRAY_TYPE
6252 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6255 /* Otherwise, if we have come to a subaggregate,
6256 and we don't have an element of its type, push into it. */
6257 else if (value != 0 && !constructor_no_implicit
6258 && value != error_mark_node
6259 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6260 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6261 || fieldcode == UNION_TYPE))
6263 push_init_level (1);
6269 push_member_name (constructor_fields);
6270 output_init_element (value, fieldtype, constructor_fields, 1);
6271 RESTORE_SPELLING_DEPTH (constructor_depth);
6274 /* Do the bookkeeping for an element that was
6275 directly output as a constructor. */
6277 /* For a record, keep track of end position of last field. */
6278 tree temp = size_binop (PLUS_EXPR,
6279 DECL_FIELD_BITPOS (constructor_fields),
6280 DECL_SIZE (constructor_fields));
6281 TREE_INT_CST_LOW (constructor_bit_index)
6282 = TREE_INT_CST_LOW (temp);
6283 TREE_INT_CST_HIGH (constructor_bit_index)
6284 = TREE_INT_CST_HIGH (temp);
6286 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6289 constructor_fields = TREE_CHAIN (constructor_fields);
6290 /* Skip any nameless bit fields at the beginning. */
6291 while (constructor_fields != 0
6292 && DECL_C_BIT_FIELD (constructor_fields)
6293 && DECL_NAME (constructor_fields) == 0)
6294 constructor_fields = TREE_CHAIN (constructor_fields);
6297 if (TREE_CODE (constructor_type) == UNION_TYPE)
6300 enum tree_code fieldcode;
6302 if (constructor_fields == 0)
6304 pedwarn_init ("excess elements in union initializer%s",
6305 " after `%s'", NULL_PTR);
6309 fieldtype = TREE_TYPE (constructor_fields);
6310 if (fieldtype != error_mark_node)
6311 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6312 fieldcode = TREE_CODE (fieldtype);
6314 /* Accept a string constant to initialize a subarray. */
6316 && fieldcode == ARRAY_TYPE
6317 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6320 /* Otherwise, if we have come to a subaggregate,
6321 and we don't have an element of its type, push into it. */
6322 else if (value != 0 && !constructor_no_implicit
6323 && value != error_mark_node
6324 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6325 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6326 || fieldcode == UNION_TYPE))
6328 push_init_level (1);
6334 push_member_name (constructor_fields);
6335 output_init_element (value, fieldtype, constructor_fields, 1);
6336 RESTORE_SPELLING_DEPTH (constructor_depth);
6339 /* Do the bookkeeping for an element that was
6340 directly output as a constructor. */
6342 TREE_INT_CST_LOW (constructor_bit_index)
6343 = TREE_INT_CST_LOW (DECL_SIZE (constructor_fields));
6344 TREE_INT_CST_HIGH (constructor_bit_index)
6345 = TREE_INT_CST_HIGH (DECL_SIZE (constructor_fields));
6347 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6350 constructor_fields = 0;
6353 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6355 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6356 enum tree_code eltcode = TREE_CODE (elttype);
6358 /* Accept a string constant to initialize a subarray. */
6360 && eltcode == ARRAY_TYPE
6361 && TREE_CODE (TREE_TYPE (elttype)) == INTEGER_TYPE
6364 /* Otherwise, if we have come to a subaggregate,
6365 and we don't have an element of its type, push into it. */
6366 else if (value != 0 && !constructor_no_implicit
6367 && value != error_mark_node
6368 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != elttype
6369 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6370 || eltcode == UNION_TYPE))
6372 push_init_level (1);
6376 if (constructor_max_index != 0
6377 && tree_int_cst_lt (constructor_max_index, constructor_index))
6379 pedwarn_init ("excess elements in array initializer%s",
6380 " after `%s'", NULL_PTR);
6384 /* In the case of [LO .. HI] = VALUE, only evaluate VALUE once. */
6385 if (constructor_range_end)
6386 value = save_expr (value);
6388 /* Now output the actual element.
6389 Ordinarily, output once.
6390 If there is a range, repeat it till we advance past the range. */
6397 push_array_bounds (TREE_INT_CST_LOW (constructor_index));
6398 output_init_element (value, elttype, constructor_index, 1);
6399 RESTORE_SPELLING_DEPTH (constructor_depth);
6402 tem = size_binop (PLUS_EXPR, constructor_index,
6404 TREE_INT_CST_LOW (constructor_index)
6405 = TREE_INT_CST_LOW (tem);
6406 TREE_INT_CST_HIGH (constructor_index)
6407 = TREE_INT_CST_HIGH (tem);
6410 /* If we are doing the bookkeeping for an element that was
6411 directly output as a constructor,
6412 we must update constructor_unfilled_index. */
6414 TREE_INT_CST_LOW (constructor_unfilled_index)
6415 = TREE_INT_CST_LOW (constructor_index);
6416 TREE_INT_CST_HIGH (constructor_unfilled_index)
6417 = TREE_INT_CST_HIGH (constructor_index);
6420 while (! (constructor_range_end == 0
6421 || tree_int_cst_lt (constructor_range_end,
6422 constructor_index)));
6427 /* Handle the sole element allowed in a braced initializer
6428 for a scalar variable. */
6429 if (constructor_fields == 0)
6431 pedwarn_init ("excess elements in scalar initializer%s",
6432 " after `%s'", NULL_PTR);
6437 output_init_element (value, constructor_type, NULL_TREE, 1);
6438 constructor_fields = 0;
6442 /* If the (lexically) previous elments are not now saved,
6443 we can discard the storage for them. */
6444 if (constructor_incremental && constructor_pending_elts == 0 && value != 0
6445 && constructor_stack == 0)
6449 /* Expand an ASM statement with operands, handling output operands
6450 that are not variables or INDIRECT_REFS by transforming such
6451 cases into cases that expand_asm_operands can handle.
6453 Arguments are same as for expand_asm_operands. */
6456 c_expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line)
6457 tree string, outputs, inputs, clobbers;
6462 int noutputs = list_length (outputs);
6464 /* o[I] is the place that output number I should be written. */
6465 register tree *o = (tree *) alloca (noutputs * sizeof (tree));
6468 if (TREE_CODE (string) == ADDR_EXPR)
6469 string = TREE_OPERAND (string, 0);
6470 if (TREE_CODE (string) != STRING_CST)
6472 error ("asm template is not a string constant");
6476 /* Record the contents of OUTPUTS before it is modified. */
6477 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6478 o[i] = TREE_VALUE (tail);
6480 /* Perform default conversions on array and function inputs. */
6481 /* Don't do this for other types--
6482 it would screw up operands expected to be in memory. */
6483 for (i = 0, tail = inputs; tail; tail = TREE_CHAIN (tail), i++)
6484 if (TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == ARRAY_TYPE
6485 || TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == FUNCTION_TYPE)
6486 TREE_VALUE (tail) = default_conversion (TREE_VALUE (tail));
6488 /* Generate the ASM_OPERANDS insn;
6489 store into the TREE_VALUEs of OUTPUTS some trees for
6490 where the values were actually stored. */
6491 expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line);
6493 /* Copy all the intermediate outputs into the specified outputs. */
6494 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6496 if (o[i] != TREE_VALUE (tail))
6498 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
6502 /* Detect modification of read-only values.
6503 (Otherwise done by build_modify_expr.) */
6506 tree type = TREE_TYPE (o[i]);
6507 if (TREE_READONLY (o[i])
6508 || TYPE_READONLY (type)
6509 || ((TREE_CODE (type) == RECORD_TYPE
6510 || TREE_CODE (type) == UNION_TYPE)
6511 && C_TYPE_FIELDS_READONLY (type)))
6512 readonly_warning (o[i], "modification by `asm'");
6516 /* Those MODIFY_EXPRs could do autoincrements. */
6520 /* Expand a C `return' statement.
6521 RETVAL is the expression for what to return,
6522 or a null pointer for `return;' with no value. */
6525 c_expand_return (retval)
6528 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6530 if (TREE_THIS_VOLATILE (current_function_decl))
6531 warning ("function declared `noreturn' has a `return' statement");
6535 current_function_returns_null = 1;
6536 if (warn_return_type && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6537 warning ("`return' with no value, in function returning non-void");
6538 expand_null_return ();
6540 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6542 current_function_returns_null = 1;
6543 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6544 pedwarn ("`return' with a value, in function returning void");
6545 expand_return (retval);
6549 tree t = convert_for_assignment (valtype, retval, "return",
6550 NULL_TREE, NULL_TREE, 0);
6551 tree res = DECL_RESULT (current_function_decl);
6554 if (t == error_mark_node)
6557 inner = t = convert (TREE_TYPE (res), t);
6559 /* Strip any conversions, additions, and subtractions, and see if
6560 we are returning the address of a local variable. Warn if so. */
6563 switch (TREE_CODE (inner))
6565 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6567 inner = TREE_OPERAND (inner, 0);
6571 /* If the second operand of the MINUS_EXPR has a pointer
6572 type (or is converted from it), this may be valid, so
6573 don't give a warning. */
6575 tree op1 = TREE_OPERAND (inner, 1);
6577 while (! POINTER_TYPE_P (TREE_TYPE (op1))
6578 && (TREE_CODE (op1) == NOP_EXPR
6579 || TREE_CODE (op1) == NON_LVALUE_EXPR
6580 || TREE_CODE (op1) == CONVERT_EXPR))
6581 op1 = TREE_OPERAND (op1, 0);
6583 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6586 inner = TREE_OPERAND (inner, 0);
6591 inner = TREE_OPERAND (inner, 0);
6593 while (TREE_CODE_CLASS (TREE_CODE (inner)) == 'r')
6594 inner = TREE_OPERAND (inner, 0);
6596 if (TREE_CODE (inner) == VAR_DECL
6597 && ! DECL_EXTERNAL (inner)
6598 && ! TREE_STATIC (inner)
6599 && DECL_CONTEXT (inner) == current_function_decl)
6600 warning ("function returns address of local variable");
6607 t = build (MODIFY_EXPR, TREE_TYPE (res), res, t);
6608 TREE_SIDE_EFFECTS (t) = 1;
6610 current_function_returns_value = 1;
6614 /* Start a C switch statement, testing expression EXP.
6615 Return EXP if it is valid, an error node otherwise. */
6618 c_expand_start_case (exp)
6621 register enum tree_code code = TREE_CODE (TREE_TYPE (exp));
6622 tree type = TREE_TYPE (exp);
6624 if (code != INTEGER_TYPE && code != ENUMERAL_TYPE && code != ERROR_MARK)
6626 error ("switch quantity not an integer");
6627 exp = error_mark_node;
6632 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6634 if (warn_traditional
6635 && (type == long_integer_type_node
6636 || type == long_unsigned_type_node))
6637 pedwarn ("`long' switch expression not converted to `int' in ANSI C");
6639 exp = default_conversion (exp);
6640 type = TREE_TYPE (exp);
6641 index = get_unwidened (exp, NULL_TREE);
6642 /* We can't strip a conversion from a signed type to an unsigned,
6643 because if we did, int_fits_type_p would do the wrong thing
6644 when checking case values for being in range,
6645 and it's too hard to do the right thing. */
6646 if (TREE_UNSIGNED (TREE_TYPE (exp))
6647 == TREE_UNSIGNED (TREE_TYPE (index)))
6651 expand_start_case (1, exp, type, "switch statement");