1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 88, 91-97, 1998 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). */
44 /* Nonzero if we've already printed a "missing braces around initializer"
45 message within this initializer. */
46 static int missing_braces_mentioned;
48 static tree qualify_type PROTO((tree, tree));
49 static int comp_target_types PROTO((tree, tree));
50 static int function_types_compatible_p PROTO((tree, tree));
51 static int type_lists_compatible_p PROTO((tree, tree));
52 static tree decl_constant_value PROTO((tree));
53 static tree lookup_field PROTO((tree, tree, tree *));
54 static tree convert_arguments PROTO((tree, tree, tree, tree));
55 static tree pointer_int_sum PROTO((enum tree_code, tree, tree));
56 static tree pointer_diff PROTO((tree, tree));
57 static tree unary_complex_lvalue PROTO((enum tree_code, tree));
58 static void pedantic_lvalue_warning PROTO((enum tree_code));
59 static tree internal_build_compound_expr PROTO((tree, int));
60 static tree convert_for_assignment PROTO((tree, tree, const char *, tree,
62 static void warn_for_assignment PROTO((const char *, const char *,
64 static tree valid_compound_expr_initializer PROTO((tree, tree));
65 static void push_string PROTO((const char *));
66 static void push_member_name PROTO((tree));
67 static void push_array_bounds PROTO((int));
68 static int spelling_length PROTO((void));
69 static char *print_spelling PROTO((char *));
70 static void warning_init PROTO((const char *));
71 static tree digest_init PROTO((tree, tree, int, int));
72 static void check_init_type_bitfields PROTO((tree));
73 static void output_init_element PROTO((tree, tree, tree, int));
74 static void output_pending_init_elements PROTO((int));
75 static void add_pending_init PROTO((tree, tree));
76 static int pending_init_member PROTO((tree));
78 /* Do `exp = require_complete_type (exp);' to make sure exp
79 does not have an incomplete type. (That includes void types.) */
82 require_complete_type (value)
85 tree type = TREE_TYPE (value);
87 if (TREE_CODE (value) == ERROR_MARK)
88 return error_mark_node;
90 /* First, detect a valid value with a complete type. */
91 if (TYPE_SIZE (type) != 0
92 && type != void_type_node)
95 incomplete_type_error (value, type);
96 return error_mark_node;
99 /* Print an error message for invalid use of an incomplete type.
100 VALUE is the expression that was used (or 0 if that isn't known)
101 and TYPE is the type that was invalid. */
104 incomplete_type_error (value, type)
108 const char *type_code_string;
110 /* Avoid duplicate error message. */
111 if (TREE_CODE (type) == ERROR_MARK)
114 if (value != 0 && (TREE_CODE (value) == VAR_DECL
115 || TREE_CODE (value) == PARM_DECL))
116 error ("`%s' has an incomplete type",
117 IDENTIFIER_POINTER (DECL_NAME (value)));
121 /* We must print an error message. Be clever about what it says. */
123 switch (TREE_CODE (type))
126 type_code_string = "struct";
130 type_code_string = "union";
134 type_code_string = "enum";
138 error ("invalid use of void expression");
142 if (TYPE_DOMAIN (type))
144 type = TREE_TYPE (type);
147 error ("invalid use of array with unspecified bounds");
154 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
155 error ("invalid use of undefined type `%s %s'",
156 type_code_string, IDENTIFIER_POINTER (TYPE_NAME (type)));
158 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
159 error ("invalid use of incomplete typedef `%s'",
160 IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
164 /* Return a variant of TYPE which has all the type qualifiers of LIKE
165 as well as those of TYPE. */
168 qualify_type (type, like)
171 return c_build_qualified_type (type,
172 TYPE_QUALS (type) | TYPE_QUALS (like));
175 /* Return the common type of two types.
176 We assume that comptypes has already been done and returned 1;
177 if that isn't so, this may crash. In particular, we assume that qualifiers
180 This is the type for the result of most arithmetic operations
181 if the operands have the given two types. */
187 register enum tree_code code1;
188 register enum tree_code code2;
191 /* Save time if the two types are the same. */
193 if (t1 == t2) return t1;
195 /* If one type is nonsense, use the other. */
196 if (t1 == error_mark_node)
198 if (t2 == error_mark_node)
201 /* Merge the attributes. */
202 attributes = merge_machine_type_attributes (t1, t2);
204 /* Treat an enum type as the unsigned integer type of the same width. */
206 if (TREE_CODE (t1) == ENUMERAL_TYPE)
207 t1 = type_for_size (TYPE_PRECISION (t1), 1);
208 if (TREE_CODE (t2) == ENUMERAL_TYPE)
209 t2 = type_for_size (TYPE_PRECISION (t2), 1);
211 code1 = TREE_CODE (t1);
212 code2 = TREE_CODE (t2);
214 /* If one type is complex, form the common type of the non-complex
215 components, then make that complex. Use T1 or T2 if it is the
217 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
219 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
220 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
221 tree subtype = common_type (subtype1, subtype2);
223 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
224 return build_type_attribute_variant (t1, attributes);
225 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
226 return build_type_attribute_variant (t2, attributes);
228 return build_type_attribute_variant (build_complex_type (subtype),
236 /* If only one is real, use it as the result. */
238 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
239 return build_type_attribute_variant (t1, attributes);
241 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
242 return build_type_attribute_variant (t2, attributes);
244 /* Both real or both integers; use the one with greater precision. */
246 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
247 return build_type_attribute_variant (t1, attributes);
248 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
249 return build_type_attribute_variant (t2, attributes);
251 /* Same precision. Prefer longs to ints even when same size. */
253 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
254 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
255 return build_type_attribute_variant (long_unsigned_type_node,
258 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
259 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
261 /* But preserve unsignedness from the other type,
262 since long cannot hold all the values of an unsigned int. */
263 if (TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
264 t1 = long_unsigned_type_node;
266 t1 = long_integer_type_node;
267 return build_type_attribute_variant (t1, attributes);
270 /* Likewise, prefer long double to double even if same size. */
271 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
272 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
273 return build_type_attribute_variant (long_double_type_node,
276 /* Otherwise prefer the unsigned one. */
278 if (TREE_UNSIGNED (t1))
279 return build_type_attribute_variant (t1, attributes);
281 return build_type_attribute_variant (t2, attributes);
284 /* For two pointers, do this recursively on the target type,
285 and combine the qualifiers of the two types' targets. */
286 /* This code was turned off; I don't know why.
287 But ANSI C specifies doing this with the qualifiers.
288 So I turned it on again. */
290 tree pointed_to_1 = TREE_TYPE (t1);
291 tree pointed_to_2 = TREE_TYPE (t2);
292 tree target = common_type (TYPE_MAIN_VARIANT (pointed_to_1),
293 TYPE_MAIN_VARIANT (pointed_to_2));
294 t1 = build_pointer_type (c_build_qualified_type
296 TYPE_QUALS (pointed_to_1) |
297 TYPE_QUALS (pointed_to_2)));
298 return build_type_attribute_variant (t1, attributes);
301 t1 = build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2)));
302 return build_type_attribute_variant (t1, attributes);
307 tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
308 /* Save space: see if the result is identical to one of the args. */
309 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
310 return build_type_attribute_variant (t1, attributes);
311 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
312 return build_type_attribute_variant (t2, attributes);
313 /* Merge the element types, and have a size if either arg has one. */
314 t1 = build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
315 return build_type_attribute_variant (t1, attributes);
319 /* Function types: prefer the one that specified arg types.
320 If both do, merge the arg types. Also merge the return types. */
322 tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
323 tree p1 = TYPE_ARG_TYPES (t1);
324 tree p2 = TYPE_ARG_TYPES (t2);
329 /* Save space: see if the result is identical to one of the args. */
330 if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2))
331 return build_type_attribute_variant (t1, attributes);
332 if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1))
333 return build_type_attribute_variant (t2, attributes);
335 /* Simple way if one arg fails to specify argument types. */
336 if (TYPE_ARG_TYPES (t1) == 0)
338 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
339 return build_type_attribute_variant (t1, attributes);
341 if (TYPE_ARG_TYPES (t2) == 0)
343 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
344 return build_type_attribute_variant (t1, attributes);
347 /* If both args specify argument types, we must merge the two
348 lists, argument by argument. */
350 len = list_length (p1);
353 for (i = 0; i < len; i++)
354 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
359 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
361 /* A null type means arg type is not specified.
362 Take whatever the other function type has. */
363 if (TREE_VALUE (p1) == 0)
365 TREE_VALUE (n) = TREE_VALUE (p2);
368 if (TREE_VALUE (p2) == 0)
370 TREE_VALUE (n) = TREE_VALUE (p1);
374 /* Given wait (union {union wait *u; int *i} *)
375 and wait (union wait *),
376 prefer union wait * as type of parm. */
377 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
378 && TREE_VALUE (p1) != TREE_VALUE (p2))
381 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
382 memb; memb = TREE_CHAIN (memb))
383 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2)))
385 TREE_VALUE (n) = TREE_VALUE (p2);
387 pedwarn ("function types not truly compatible in ANSI C");
391 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
392 && TREE_VALUE (p2) != TREE_VALUE (p1))
395 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
396 memb; memb = TREE_CHAIN (memb))
397 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1)))
399 TREE_VALUE (n) = TREE_VALUE (p1);
401 pedwarn ("function types not truly compatible in ANSI C");
405 TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2));
409 t1 = build_function_type (valtype, newargs);
410 /* ... falls through ... */
414 return build_type_attribute_variant (t1, attributes);
419 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
420 or various other operations. Return 2 if they are compatible
421 but a warning may be needed if you use them together. */
424 comptypes (type1, type2)
427 register tree t1 = type1;
428 register tree t2 = type2;
431 /* Suppress errors caused by previously reported errors. */
433 if (t1 == t2 || !t1 || !t2
434 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
437 /* Treat an enum type as the integer type of the same width and
440 if (TREE_CODE (t1) == ENUMERAL_TYPE)
441 t1 = type_for_size (TYPE_PRECISION (t1), TREE_UNSIGNED (t1));
442 if (TREE_CODE (t2) == ENUMERAL_TYPE)
443 t2 = type_for_size (TYPE_PRECISION (t2), TREE_UNSIGNED (t2));
448 /* Different classes of types can't be compatible. */
450 if (TREE_CODE (t1) != TREE_CODE (t2)) return 0;
452 /* Qualifiers must match. */
454 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
457 /* Allow for two different type nodes which have essentially the same
458 definition. Note that we already checked for equality of the type
459 qualifiers (just above). */
461 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
464 #ifndef COMP_TYPE_ATTRIBUTES
465 #define COMP_TYPE_ATTRIBUTES(t1,t2) 1
468 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
469 if (! (attrval = COMP_TYPE_ATTRIBUTES (t1, t2)))
472 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
475 switch (TREE_CODE (t1))
478 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
479 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
483 val = function_types_compatible_p (t1, t2);
488 tree d1 = TYPE_DOMAIN (t1);
489 tree d2 = TYPE_DOMAIN (t2);
492 /* Target types must match incl. qualifiers. */
493 if (TREE_TYPE (t1) != TREE_TYPE (t2)
494 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
497 /* Sizes must match unless one is missing or variable. */
498 if (d1 == 0 || d2 == 0 || d1 == d2
499 || TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
500 || TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
501 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST
502 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)
505 if (! ((TREE_INT_CST_LOW (TYPE_MIN_VALUE (d1))
506 == TREE_INT_CST_LOW (TYPE_MIN_VALUE (d2)))
507 && (TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d1))
508 == TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d2)))
509 && (TREE_INT_CST_LOW (TYPE_MAX_VALUE (d1))
510 == TREE_INT_CST_LOW (TYPE_MAX_VALUE (d2)))
511 && (TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d1))
512 == TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d2)))))
518 if (maybe_objc_comptypes (t1, t2, 0) == 1)
525 return attrval == 2 && val == 1 ? 2 : val;
528 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
529 ignoring their qualifiers. */
532 comp_target_types (ttl, ttr)
537 /* Give maybe_objc_comptypes a crack at letting these types through. */
538 if ((val = maybe_objc_comptypes (ttl, ttr, 1)) >= 0)
541 val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)),
542 TYPE_MAIN_VARIANT (TREE_TYPE (ttr)));
544 if (val == 2 && pedantic)
545 pedwarn ("types are not quite compatible");
549 /* Subroutines of `comptypes'. */
551 /* Return 1 if two function types F1 and F2 are compatible.
552 If either type specifies no argument types,
553 the other must specify a fixed number of self-promoting arg types.
554 Otherwise, if one type specifies only the number of arguments,
555 the other must specify that number of self-promoting arg types.
556 Otherwise, the argument types must match. */
559 function_types_compatible_p (f1, f2)
563 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
567 if (!(TREE_TYPE (f1) == TREE_TYPE (f2)
568 || (val = comptypes (TREE_TYPE (f1), TREE_TYPE (f2)))))
571 args1 = TYPE_ARG_TYPES (f1);
572 args2 = TYPE_ARG_TYPES (f2);
574 /* An unspecified parmlist matches any specified parmlist
575 whose argument types don't need default promotions. */
579 if (!self_promoting_args_p (args2))
581 /* If one of these types comes from a non-prototype fn definition,
582 compare that with the other type's arglist.
583 If they don't match, ask for a warning (but no error). */
584 if (TYPE_ACTUAL_ARG_TYPES (f1)
585 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
591 if (!self_promoting_args_p (args1))
593 if (TYPE_ACTUAL_ARG_TYPES (f2)
594 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
599 /* Both types have argument lists: compare them and propagate results. */
600 val1 = type_lists_compatible_p (args1, args2);
601 return val1 != 1 ? val1 : val;
604 /* Check two lists of types for compatibility,
605 returning 0 for incompatible, 1 for compatible,
606 or 2 for compatible with warning. */
609 type_lists_compatible_p (args1, args2)
612 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
618 if (args1 == 0 && args2 == 0)
620 /* If one list is shorter than the other,
621 they fail to match. */
622 if (args1 == 0 || args2 == 0)
624 /* A null pointer instead of a type
625 means there is supposed to be an argument
626 but nothing is specified about what type it has.
627 So match anything that self-promotes. */
628 if (TREE_VALUE (args1) == 0)
630 if (simple_type_promotes_to (TREE_VALUE (args2)) != NULL_TREE)
633 else if (TREE_VALUE (args2) == 0)
635 if (simple_type_promotes_to (TREE_VALUE (args1)) != NULL_TREE)
638 else if (! (newval = comptypes (TREE_VALUE (args1), TREE_VALUE (args2))))
640 /* Allow wait (union {union wait *u; int *i} *)
641 and wait (union wait *) to be compatible. */
642 if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE
643 && (TYPE_NAME (TREE_VALUE (args1)) == 0
644 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args1)))
645 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST
646 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)),
647 TYPE_SIZE (TREE_VALUE (args2))))
650 for (memb = TYPE_FIELDS (TREE_VALUE (args1));
651 memb; memb = TREE_CHAIN (memb))
652 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2)))
657 else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE
658 && (TYPE_NAME (TREE_VALUE (args2)) == 0
659 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args2)))
660 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST
661 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)),
662 TYPE_SIZE (TREE_VALUE (args1))))
665 for (memb = TYPE_FIELDS (TREE_VALUE (args2));
666 memb; memb = TREE_CHAIN (memb))
667 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1)))
676 /* comptypes said ok, but record if it said to warn. */
680 args1 = TREE_CHAIN (args1);
681 args2 = TREE_CHAIN (args2);
685 /* Compute the value of the `sizeof' operator. */
691 enum tree_code code = TREE_CODE (type);
694 if (code == FUNCTION_TYPE)
696 if (pedantic || warn_pointer_arith)
697 pedwarn ("sizeof applied to a function type");
700 if (code == VOID_TYPE)
702 if (pedantic || warn_pointer_arith)
703 pedwarn ("sizeof applied to a void type");
706 if (code == ERROR_MARK)
708 if (TYPE_SIZE (type) == 0)
710 error ("sizeof applied to an incomplete type");
714 /* Convert in case a char is more than one unit. */
715 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
716 size_int (TYPE_PRECISION (char_type_node)));
717 t = convert (sizetype, t);
718 /* size_binop does not put the constant in range, so do it now. */
719 if (TREE_CODE (t) == INTEGER_CST && force_fit_type (t, 0))
720 TREE_CONSTANT_OVERFLOW (t) = TREE_OVERFLOW (t) = 1;
725 c_sizeof_nowarn (type)
728 enum tree_code code = TREE_CODE (type);
731 if (code == FUNCTION_TYPE
733 || code == ERROR_MARK)
735 if (TYPE_SIZE (type) == 0)
738 /* Convert in case a char is more than one unit. */
739 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
740 size_int (TYPE_PRECISION (char_type_node)));
741 t = convert (sizetype, t);
742 force_fit_type (t, 0);
746 /* Compute the size to increment a pointer by. */
749 c_size_in_bytes (type)
752 enum tree_code code = TREE_CODE (type);
755 if (code == FUNCTION_TYPE)
757 if (code == VOID_TYPE)
759 if (code == ERROR_MARK)
761 if (TYPE_SIZE (type) == 0)
763 error ("arithmetic on pointer to an incomplete type");
767 /* Convert in case a char is more than one unit. */
768 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
769 size_int (BITS_PER_UNIT));
770 t = convert (sizetype, t);
771 force_fit_type (t, 0);
775 /* Implement the __alignof keyword: Return the minimum required
776 alignment of TYPE, measured in bytes. */
782 enum tree_code code = TREE_CODE (type);
784 if (code == FUNCTION_TYPE)
785 return size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
787 if (code == VOID_TYPE || code == ERROR_MARK)
790 return size_int (TYPE_ALIGN (type) / BITS_PER_UNIT);
793 /* Implement the __alignof keyword: Return the minimum required
794 alignment of EXPR, measured in bytes. For VAR_DECL's and
795 FIELD_DECL's return DECL_ALIGN (which can be set from an
796 "aligned" __attribute__ specification). */
799 c_alignof_expr (expr)
802 if (TREE_CODE (expr) == VAR_DECL)
803 return size_int (DECL_ALIGN (expr) / BITS_PER_UNIT);
805 if (TREE_CODE (expr) == COMPONENT_REF
806 && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1)))
808 error ("`__alignof' applied to a bit-field");
811 else if (TREE_CODE (expr) == COMPONENT_REF
812 && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
813 return size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT);
815 if (TREE_CODE (expr) == INDIRECT_REF)
817 tree t = TREE_OPERAND (expr, 0);
819 int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
821 while (TREE_CODE (t) == NOP_EXPR
822 && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
826 t = TREE_OPERAND (t, 0);
827 thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
828 if (thisalign > bestalign)
829 best = t, bestalign = thisalign;
831 return c_alignof (TREE_TYPE (TREE_TYPE (best)));
834 return c_alignof (TREE_TYPE (expr));
837 /* Return either DECL or its known constant value (if it has one). */
840 decl_constant_value (decl)
843 if (/* Don't change a variable array bound or initial value to a constant
844 in a place where a variable is invalid. */
845 current_function_decl != 0
847 && ! TREE_THIS_VOLATILE (decl)
848 && TREE_READONLY (decl) && ! ITERATOR_P (decl)
849 && DECL_INITIAL (decl) != 0
850 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
851 /* This is invalid if initial value is not constant.
852 If it has either a function call, a memory reference,
853 or a variable, then re-evaluating it could give different results. */
854 && TREE_CONSTANT (DECL_INITIAL (decl))
855 /* Check for cases where this is sub-optimal, even though valid. */
856 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR
857 && DECL_MODE (decl) != BLKmode)
858 return DECL_INITIAL (decl);
862 /* Perform default promotions for C data used in expressions.
863 Arrays and functions are converted to pointers;
864 enumeral types or short or char, to int.
865 In addition, manifest constants symbols are replaced by their values. */
868 default_conversion (exp)
871 register tree type = TREE_TYPE (exp);
872 register enum tree_code code = TREE_CODE (type);
874 /* Constants can be used directly unless they're not loadable. */
875 if (TREE_CODE (exp) == CONST_DECL)
876 exp = DECL_INITIAL (exp);
878 /* Replace a nonvolatile const static variable with its value unless
879 it is an array, in which case we must be sure that taking the
880 address of the array produces consistent results. */
881 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
883 exp = decl_constant_value (exp);
884 type = TREE_TYPE (exp);
887 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
889 /* Do not use STRIP_NOPS here! It will remove conversions from pointer
890 to integer and cause infinite recursion. */
891 while (TREE_CODE (exp) == NON_LVALUE_EXPR
892 || (TREE_CODE (exp) == NOP_EXPR
893 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
894 exp = TREE_OPERAND (exp, 0);
896 /* Normally convert enums to int,
897 but convert wide enums to something wider. */
898 if (code == ENUMERAL_TYPE)
900 type = type_for_size (MAX (TYPE_PRECISION (type),
901 TYPE_PRECISION (integer_type_node)),
903 || (TYPE_PRECISION (type)
904 >= TYPE_PRECISION (integer_type_node)))
905 && TREE_UNSIGNED (type)));
906 return convert (type, exp);
909 if (TREE_CODE (exp) == COMPONENT_REF
910 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1)))
912 tree width = DECL_SIZE (TREE_OPERAND (exp, 1));
913 HOST_WIDE_INT low = TREE_INT_CST_LOW (width);
915 /* If it's thinner than an int, promote it like a
916 C_PROMOTING_INTEGER_TYPE_P, otherwise leave it alone. */
918 if (low < TYPE_PRECISION (integer_type_node))
920 if (flag_traditional && TREE_UNSIGNED (type))
921 return convert (unsigned_type_node, exp);
923 return convert (integer_type_node, exp);
927 if (C_PROMOTING_INTEGER_TYPE_P (type))
929 /* Traditionally, unsignedness is preserved in default promotions.
930 Also preserve unsignedness if not really getting any wider. */
931 if (TREE_UNSIGNED (type)
933 || TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
934 return convert (unsigned_type_node, exp);
935 return convert (integer_type_node, exp);
937 if (flag_traditional && !flag_allow_single_precision
938 && TYPE_MAIN_VARIANT (type) == float_type_node)
939 return convert (double_type_node, exp);
940 if (code == VOID_TYPE)
942 error ("void value not ignored as it ought to be");
943 return error_mark_node;
945 if (code == FUNCTION_TYPE)
947 return build_unary_op (ADDR_EXPR, exp, 0);
949 if (code == ARRAY_TYPE)
952 tree restype = TREE_TYPE (type);
957 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r'
958 || TREE_CODE_CLASS (TREE_CODE (exp)) == 'd')
960 constp = TREE_READONLY (exp);
961 volatilep = TREE_THIS_VOLATILE (exp);
964 if (TYPE_QUALS (type) || constp || volatilep)
966 = c_build_qualified_type (restype,
968 | (constp * TYPE_QUAL_CONST)
969 | (volatilep * TYPE_QUAL_VOLATILE));
971 if (TREE_CODE (exp) == INDIRECT_REF)
972 return convert (TYPE_POINTER_TO (restype),
973 TREE_OPERAND (exp, 0));
975 if (TREE_CODE (exp) == COMPOUND_EXPR)
977 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
978 return build (COMPOUND_EXPR, TREE_TYPE (op1),
979 TREE_OPERAND (exp, 0), op1);
983 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
985 error ("invalid use of non-lvalue array");
986 return error_mark_node;
989 ptrtype = build_pointer_type (restype);
991 if (TREE_CODE (exp) == VAR_DECL)
993 /* ??? This is not really quite correct
994 in that the type of the operand of ADDR_EXPR
995 is not the target type of the type of the ADDR_EXPR itself.
996 Question is, can this lossage be avoided? */
997 adr = build1 (ADDR_EXPR, ptrtype, exp);
998 if (mark_addressable (exp) == 0)
999 return error_mark_node;
1000 TREE_CONSTANT (adr) = staticp (exp);
1001 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1004 /* This way is better for a COMPONENT_REF since it can
1005 simplify the offset for a component. */
1006 adr = build_unary_op (ADDR_EXPR, exp, 1);
1007 return convert (ptrtype, adr);
1012 /* Look up component name in the structure type definition.
1014 If this component name is found indirectly within an anonymous union,
1015 store in *INDIRECT the component which directly contains
1016 that anonymous union. Otherwise, set *INDIRECT to 0. */
1019 lookup_field (type, component, indirect)
1020 tree type, component;
1025 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1026 to the field elements. Use a binary search on this array to quickly
1027 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1028 will always be set for structures which have many elements. */
1030 if (TYPE_LANG_SPECIFIC (type))
1033 tree *field_array = &TYPE_LANG_SPECIFIC (type)->elts[0];
1035 field = TYPE_FIELDS (type);
1037 top = TYPE_LANG_SPECIFIC (type)->len;
1038 while (top - bot > 1)
1040 half = (top - bot + 1) >> 1;
1041 field = field_array[bot+half];
1043 if (DECL_NAME (field) == NULL_TREE)
1045 /* Step through all anon unions in linear fashion. */
1046 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1048 tree anon = 0, junk;
1050 field = field_array[bot++];
1051 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1052 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1053 anon = lookup_field (TREE_TYPE (field), component, &junk);
1055 if (anon != NULL_TREE)
1062 /* Entire record is only anon unions. */
1066 /* Restart the binary search, with new lower bound. */
1070 if (DECL_NAME (field) == component)
1072 if (DECL_NAME (field) < component)
1078 if (DECL_NAME (field_array[bot]) == component)
1079 field = field_array[bot];
1080 else if (DECL_NAME (field) != component)
1085 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1087 if (DECL_NAME (field) == NULL_TREE)
1092 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1093 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1094 anon = lookup_field (TREE_TYPE (field), component, &junk);
1096 if (anon != NULL_TREE)
1103 if (DECL_NAME (field) == component)
1108 *indirect = NULL_TREE;
1112 /* Make an expression to refer to the COMPONENT field of
1113 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1116 build_component_ref (datum, component)
1117 tree datum, component;
1119 register tree type = TREE_TYPE (datum);
1120 register enum tree_code code = TREE_CODE (type);
1121 register tree field = NULL;
1124 /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it
1125 unless we are not to support things not strictly ANSI. */
1126 switch (TREE_CODE (datum))
1130 tree value = build_component_ref (TREE_OPERAND (datum, 1), component);
1131 return build (COMPOUND_EXPR, TREE_TYPE (value),
1132 TREE_OPERAND (datum, 0), value);
1135 return build_conditional_expr
1136 (TREE_OPERAND (datum, 0),
1137 build_component_ref (TREE_OPERAND (datum, 1), component),
1138 build_component_ref (TREE_OPERAND (datum, 2), component));
1144 /* See if there is a field or component with name COMPONENT. */
1146 if (code == RECORD_TYPE || code == UNION_TYPE)
1150 if (TYPE_SIZE (type) == 0)
1152 incomplete_type_error (NULL_TREE, type);
1153 return error_mark_node;
1156 field = lookup_field (type, component, &indirect);
1160 error ("%s has no member named `%s'",
1161 code == RECORD_TYPE ? "structure" : "union",
1162 IDENTIFIER_POINTER (component));
1163 return error_mark_node;
1165 if (TREE_TYPE (field) == error_mark_node)
1166 return error_mark_node;
1168 /* If FIELD was found buried within an anonymous union,
1169 make one COMPONENT_REF to get that anonymous union,
1170 then fall thru to make a second COMPONENT_REF to get FIELD. */
1173 ref = build (COMPONENT_REF, TREE_TYPE (indirect), datum, indirect);
1174 if (TREE_READONLY (datum) || TREE_READONLY (indirect))
1175 TREE_READONLY (ref) = 1;
1176 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (indirect))
1177 TREE_THIS_VOLATILE (ref) = 1;
1181 ref = build (COMPONENT_REF, TREE_TYPE (field), datum, field);
1183 if (TREE_READONLY (datum) || TREE_READONLY (field))
1184 TREE_READONLY (ref) = 1;
1185 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (field))
1186 TREE_THIS_VOLATILE (ref) = 1;
1190 else if (code != ERROR_MARK)
1191 error ("request for member `%s' in something not a structure or union",
1192 IDENTIFIER_POINTER (component));
1194 return error_mark_node;
1197 /* Given an expression PTR for a pointer, return an expression
1198 for the value pointed to.
1199 ERRORSTRING is the name of the operator to appear in error messages. */
1202 build_indirect_ref (ptr, errorstring)
1204 const char *errorstring;
1206 register tree pointer = default_conversion (ptr);
1207 register tree type = TREE_TYPE (pointer);
1209 if (TREE_CODE (type) == POINTER_TYPE)
1211 if (TREE_CODE (pointer) == ADDR_EXPR
1213 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1214 == TREE_TYPE (type)))
1215 return TREE_OPERAND (pointer, 0);
1218 tree t = TREE_TYPE (type);
1219 register tree ref = build1 (INDIRECT_REF,
1220 TYPE_MAIN_VARIANT (t), pointer);
1222 if (TYPE_SIZE (t) == 0 && TREE_CODE (t) != ARRAY_TYPE)
1224 error ("dereferencing pointer to incomplete type");
1225 return error_mark_node;
1227 if (TREE_CODE (t) == VOID_TYPE && skip_evaluation == 0)
1228 warning ("dereferencing `void *' pointer");
1230 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1231 so that we get the proper error message if the result is used
1232 to assign to. Also, &* is supposed to be a no-op.
1233 And ANSI C seems to specify that the type of the result
1234 should be the const type. */
1235 /* A de-reference of a pointer to const is not a const. It is valid
1236 to change it via some other pointer. */
1237 TREE_READONLY (ref) = TYPE_READONLY (t);
1238 TREE_SIDE_EFFECTS (ref)
1239 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer) || flag_volatile;
1240 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1244 else if (TREE_CODE (pointer) != ERROR_MARK)
1245 error ("invalid type argument of `%s'", errorstring);
1246 return error_mark_node;
1249 /* This handles expressions of the form "a[i]", which denotes
1252 This is logically equivalent in C to *(a+i), but we may do it differently.
1253 If A is a variable or a member, we generate a primitive ARRAY_REF.
1254 This avoids forcing the array out of registers, and can work on
1255 arrays that are not lvalues (for example, members of structures returned
1259 build_array_ref (array, index)
1264 error ("subscript missing in array reference");
1265 return error_mark_node;
1268 if (TREE_TYPE (array) == error_mark_node
1269 || TREE_TYPE (index) == error_mark_node)
1270 return error_mark_node;
1272 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
1273 && TREE_CODE (array) != INDIRECT_REF)
1277 /* Subscripting with type char is likely to lose
1278 on a machine where chars are signed.
1279 So warn on any machine, but optionally.
1280 Don't warn for unsigned char since that type is safe.
1281 Don't warn for signed char because anyone who uses that
1282 must have done so deliberately. */
1283 if (warn_char_subscripts
1284 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1285 warning ("array subscript has type `char'");
1287 /* Apply default promotions *after* noticing character types. */
1288 index = default_conversion (index);
1290 /* Require integer *after* promotion, for sake of enums. */
1291 if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE)
1293 error ("array subscript is not an integer");
1294 return error_mark_node;
1297 /* An array that is indexed by a non-constant
1298 cannot be stored in a register; we must be able to do
1299 address arithmetic on its address.
1300 Likewise an array of elements of variable size. */
1301 if (TREE_CODE (index) != INTEGER_CST
1302 || (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))) != 0
1303 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1305 if (mark_addressable (array) == 0)
1306 return error_mark_node;
1308 /* An array that is indexed by a constant value which is not within
1309 the array bounds cannot be stored in a register either; because we
1310 would get a crash in store_bit_field/extract_bit_field when trying
1311 to access a non-existent part of the register. */
1312 if (TREE_CODE (index) == INTEGER_CST
1313 && TYPE_VALUES (TREE_TYPE (array))
1314 && ! int_fits_type_p (index, TYPE_VALUES (TREE_TYPE (array))))
1316 if (mark_addressable (array) == 0)
1317 return error_mark_node;
1320 if (pedantic && !lvalue_p (array))
1322 if (DECL_REGISTER (array))
1323 pedwarn ("ANSI C forbids subscripting `register' array");
1325 pedwarn ("ANSI C forbids subscripting non-lvalue array");
1331 while (TREE_CODE (foo) == COMPONENT_REF)
1332 foo = TREE_OPERAND (foo, 0);
1333 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
1334 pedwarn ("ANSI C forbids subscripting non-lvalue array");
1337 type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array)));
1338 rval = build (ARRAY_REF, type, array, index);
1339 /* Array ref is const/volatile if the array elements are
1340 or if the array is. */
1341 TREE_READONLY (rval)
1342 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1343 | TREE_READONLY (array));
1344 TREE_SIDE_EFFECTS (rval)
1345 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1346 | TREE_SIDE_EFFECTS (array));
1347 TREE_THIS_VOLATILE (rval)
1348 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1349 /* This was added by rms on 16 Nov 91.
1350 It fixes vol struct foo *a; a->elts[1]
1351 in an inline function.
1352 Hope it doesn't break something else. */
1353 | TREE_THIS_VOLATILE (array));
1354 return require_complete_type (fold (rval));
1358 tree ar = default_conversion (array);
1359 tree ind = default_conversion (index);
1361 /* Do the same warning check as above, but only on the part that's
1362 syntactically the index and only if it is also semantically
1364 if (warn_char_subscripts
1365 && TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE
1366 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1367 warning ("subscript has type `char'");
1369 /* Put the integer in IND to simplify error checking. */
1370 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
1377 if (ar == error_mark_node)
1380 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE
1381 || TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) == FUNCTION_TYPE)
1383 error ("subscripted value is neither array nor pointer");
1384 return error_mark_node;
1386 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
1388 error ("array subscript is not an integer");
1389 return error_mark_node;
1392 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0),
1397 /* Build a function call to function FUNCTION with parameters PARAMS.
1398 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1399 TREE_VALUE of each node is a parameter-expression.
1400 FUNCTION's data type may be a function type or a pointer-to-function. */
1403 build_function_call (function, params)
1404 tree function, params;
1406 register tree fntype, fundecl = 0;
1407 register tree coerced_params;
1408 tree name = NULL_TREE, assembler_name = NULL_TREE;
1410 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1411 STRIP_TYPE_NOPS (function);
1413 /* Convert anything with function type to a pointer-to-function. */
1414 if (TREE_CODE (function) == FUNCTION_DECL)
1416 name = DECL_NAME (function);
1417 assembler_name = DECL_ASSEMBLER_NAME (function);
1419 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1420 (because calling an inline function does not mean the function
1421 needs to be separately compiled). */
1422 fntype = build_type_variant (TREE_TYPE (function),
1423 TREE_READONLY (function),
1424 TREE_THIS_VOLATILE (function));
1426 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
1429 function = default_conversion (function);
1431 fntype = TREE_TYPE (function);
1433 if (TREE_CODE (fntype) == ERROR_MARK)
1434 return error_mark_node;
1436 if (!(TREE_CODE (fntype) == POINTER_TYPE
1437 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
1439 error ("called object is not a function");
1440 return error_mark_node;
1443 /* fntype now gets the type of function pointed to. */
1444 fntype = TREE_TYPE (fntype);
1446 /* Convert the parameters to the types declared in the
1447 function prototype, or apply default promotions. */
1450 = convert_arguments (TYPE_ARG_TYPES (fntype), params, name, fundecl);
1452 /* Check for errors in format strings. */
1454 if (warn_format && (name || assembler_name))
1455 check_function_format (name, assembler_name, coerced_params);
1457 /* Recognize certain built-in functions so we can make tree-codes
1458 other than CALL_EXPR. We do this when it enables fold-const.c
1459 to do something useful. */
1461 if (TREE_CODE (function) == ADDR_EXPR
1462 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
1463 && DECL_BUILT_IN (TREE_OPERAND (function, 0))
1464 && DECL_BUILT_IN_CLASS (TREE_OPERAND (function, 0)) == BUILT_IN_NORMAL)
1465 switch (DECL_FUNCTION_CODE (TREE_OPERAND (function, 0)))
1470 if (coerced_params == 0)
1471 return integer_zero_node;
1472 return build_unary_op (ABS_EXPR, TREE_VALUE (coerced_params), 0);
1478 register tree result
1479 = build (CALL_EXPR, TREE_TYPE (fntype),
1480 function, coerced_params, NULL_TREE);
1482 TREE_SIDE_EFFECTS (result) = 1;
1483 if (TREE_TYPE (result) == void_type_node)
1485 return require_complete_type (result);
1489 /* Convert the argument expressions in the list VALUES
1490 to the types in the list TYPELIST. The result is a list of converted
1491 argument expressions.
1493 If TYPELIST is exhausted, or when an element has NULL as its type,
1494 perform the default conversions.
1496 PARMLIST is the chain of parm decls for the function being called.
1497 It may be 0, if that info is not available.
1498 It is used only for generating error messages.
1500 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1502 This is also where warnings about wrong number of args are generated.
1504 Both VALUES and the returned value are chains of TREE_LIST nodes
1505 with the elements of the list in the TREE_VALUE slots of those nodes. */
1508 convert_arguments (typelist, values, name, fundecl)
1509 tree typelist, values, name, fundecl;
1511 register tree typetail, valtail;
1512 register tree result = NULL;
1515 /* Scan the given expressions and types, producing individual
1516 converted arguments and pushing them on RESULT in reverse order. */
1518 for (valtail = values, typetail = typelist, parmnum = 0;
1520 valtail = TREE_CHAIN (valtail), parmnum++)
1522 register tree type = typetail ? TREE_VALUE (typetail) : 0;
1523 register tree val = TREE_VALUE (valtail);
1525 if (type == void_type_node)
1528 error ("too many arguments to function `%s'",
1529 IDENTIFIER_POINTER (name));
1531 error ("too many arguments to function");
1535 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1536 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1537 to convert automatically to a pointer. */
1538 if (TREE_CODE (val) == NON_LVALUE_EXPR)
1539 val = TREE_OPERAND (val, 0);
1541 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
1542 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE)
1543 val = default_conversion (val);
1545 val = require_complete_type (val);
1549 /* Formal parm type is specified by a function prototype. */
1552 if (TYPE_SIZE (type) == 0)
1554 error ("type of formal parameter %d is incomplete", parmnum + 1);
1559 /* Optionally warn about conversions that
1560 differ from the default conversions. */
1561 if (warn_conversion)
1563 int formal_prec = TYPE_PRECISION (type);
1565 if (INTEGRAL_TYPE_P (type)
1566 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1567 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1568 else if (TREE_CODE (type) == COMPLEX_TYPE
1569 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1570 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1571 else if (TREE_CODE (type) == REAL_TYPE
1572 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1573 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1574 else if (TREE_CODE (type) == REAL_TYPE
1575 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
1576 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1577 /* ??? At some point, messages should be written about
1578 conversions between complex types, but that's too messy
1580 else if (TREE_CODE (type) == REAL_TYPE
1581 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1583 /* Warn if any argument is passed as `float',
1584 since without a prototype it would be `double'. */
1585 if (formal_prec == TYPE_PRECISION (float_type_node))
1586 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1588 /* Detect integer changing in width or signedness. */
1589 else if (INTEGRAL_TYPE_P (type)
1590 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1592 tree would_have_been = default_conversion (val);
1593 tree type1 = TREE_TYPE (would_have_been);
1595 if (TREE_CODE (type) == ENUMERAL_TYPE
1596 && type == TREE_TYPE (val))
1597 /* No warning if function asks for enum
1598 and the actual arg is that enum type. */
1600 else if (formal_prec != TYPE_PRECISION (type1))
1601 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1602 else if (TREE_UNSIGNED (type) == TREE_UNSIGNED (type1))
1604 /* Don't complain if the formal parameter type
1605 is an enum, because we can't tell now whether
1606 the value was an enum--even the same enum. */
1607 else if (TREE_CODE (type) == ENUMERAL_TYPE)
1609 else if (TREE_CODE (val) == INTEGER_CST
1610 && int_fits_type_p (val, type))
1611 /* Change in signedness doesn't matter
1612 if a constant value is unaffected. */
1614 /* Likewise for a constant in a NOP_EXPR. */
1615 else if (TREE_CODE (val) == NOP_EXPR
1616 && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST
1617 && int_fits_type_p (TREE_OPERAND (val, 0), type))
1619 #if 0 /* We never get such tree structure here. */
1620 else if (TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE
1621 && int_fits_type_p (TYPE_MIN_VALUE (TREE_TYPE (val)), type)
1622 && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE (val)), type))
1623 /* Change in signedness doesn't matter
1624 if an enum value is unaffected. */
1627 /* If the value is extended from a narrower
1628 unsigned type, it doesn't matter whether we
1629 pass it as signed or unsigned; the value
1630 certainly is the same either way. */
1631 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
1632 && TREE_UNSIGNED (TREE_TYPE (val)))
1634 else if (TREE_UNSIGNED (type))
1635 warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1);
1637 warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1);
1641 parmval = convert_for_assignment (type, val,
1642 (char *) 0, /* arg passing */
1643 fundecl, name, parmnum + 1);
1645 if (PROMOTE_PROTOTYPES
1646 && (TREE_CODE (type) == INTEGER_TYPE
1647 || TREE_CODE (type) == ENUMERAL_TYPE)
1648 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
1649 parmval = default_conversion (parmval);
1651 result = tree_cons (NULL_TREE, parmval, result);
1653 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
1654 && (TYPE_PRECISION (TREE_TYPE (val))
1655 < TYPE_PRECISION (double_type_node)))
1656 /* Convert `float' to `double'. */
1657 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
1659 /* Convert `short' and `char' to full-size `int'. */
1660 result = tree_cons (NULL_TREE, default_conversion (val), result);
1663 typetail = TREE_CHAIN (typetail);
1666 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
1669 error ("too few arguments to function `%s'",
1670 IDENTIFIER_POINTER (name));
1672 error ("too few arguments to function");
1675 return nreverse (result);
1678 /* This is the entry point used by the parser
1679 for binary operators in the input.
1680 In addition to constructing the expression,
1681 we check for operands that were written with other binary operators
1682 in a way that is likely to confuse the user. */
1685 parser_build_binary_op (code, arg1, arg2)
1686 enum tree_code code;
1689 tree result = build_binary_op (code, arg1, arg2, 1);
1692 char class1 = TREE_CODE_CLASS (TREE_CODE (arg1));
1693 char class2 = TREE_CODE_CLASS (TREE_CODE (arg2));
1694 enum tree_code code1 = ERROR_MARK;
1695 enum tree_code code2 = ERROR_MARK;
1697 if (class1 == 'e' || class1 == '1'
1698 || class1 == '2' || class1 == '<')
1699 code1 = C_EXP_ORIGINAL_CODE (arg1);
1700 if (class2 == 'e' || class2 == '1'
1701 || class2 == '2' || class2 == '<')
1702 code2 = C_EXP_ORIGINAL_CODE (arg2);
1704 /* Check for cases such as x+y<<z which users are likely
1705 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1706 is cleared to prevent these warnings. */
1707 if (warn_parentheses)
1709 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
1711 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1712 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1713 warning ("suggest parentheses around + or - inside shift");
1716 if (code == TRUTH_ORIF_EXPR)
1718 if (code1 == TRUTH_ANDIF_EXPR
1719 || code2 == TRUTH_ANDIF_EXPR)
1720 warning ("suggest parentheses around && within ||");
1723 if (code == BIT_IOR_EXPR)
1725 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
1726 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1727 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
1728 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1729 warning ("suggest parentheses around arithmetic in operand of |");
1730 /* Check cases like x|y==z */
1731 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1732 warning ("suggest parentheses around comparison in operand of |");
1735 if (code == BIT_XOR_EXPR)
1737 if (code1 == BIT_AND_EXPR
1738 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1739 || code2 == BIT_AND_EXPR
1740 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1741 warning ("suggest parentheses around arithmetic in operand of ^");
1742 /* Check cases like x^y==z */
1743 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1744 warning ("suggest parentheses around comparison in operand of ^");
1747 if (code == BIT_AND_EXPR)
1749 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1750 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1751 warning ("suggest parentheses around + or - in operand of &");
1752 /* Check cases like x&y==z */
1753 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1754 warning ("suggest parentheses around comparison in operand of &");
1758 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1759 if (TREE_CODE_CLASS (code) == '<' && extra_warnings
1760 && (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<'))
1761 warning ("comparisons like X<=Y<=Z do not have their mathematical meaning");
1763 unsigned_conversion_warning (result, arg1);
1764 unsigned_conversion_warning (result, arg2);
1765 overflow_warning (result);
1767 class = TREE_CODE_CLASS (TREE_CODE (result));
1769 /* Record the code that was specified in the source,
1770 for the sake of warnings about confusing nesting. */
1771 if (class == 'e' || class == '1'
1772 || class == '2' || class == '<')
1773 C_SET_EXP_ORIGINAL_CODE (result, code);
1776 int flag = TREE_CONSTANT (result);
1777 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1778 so that convert_for_assignment wouldn't strip it.
1779 That way, we got warnings for things like p = (1 - 1).
1780 But it turns out we should not get those warnings. */
1781 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
1782 C_SET_EXP_ORIGINAL_CODE (result, code);
1783 TREE_CONSTANT (result) = flag;
1789 /* Build a binary-operation expression without default conversions.
1790 CODE is the kind of expression to build.
1791 This function differs from `build' in several ways:
1792 the data type of the result is computed and recorded in it,
1793 warnings are generated if arg data types are invalid,
1794 special handling for addition and subtraction of pointers is known,
1795 and some optimization is done (operations on narrow ints
1796 are done in the narrower type when that gives the same result).
1797 Constant folding is also done before the result is returned.
1799 Note that the operands will never have enumeral types, or function
1800 or array types, because either they will have the default conversions
1801 performed or they have both just been converted to some other type in which
1802 the arithmetic is to be done. */
1805 build_binary_op (code, orig_op0, orig_op1, convert_p)
1806 enum tree_code code;
1807 tree orig_op0, orig_op1;
1811 register enum tree_code code0, code1;
1814 /* Expression code to give to the expression when it is built.
1815 Normally this is CODE, which is what the caller asked for,
1816 but in some special cases we change it. */
1817 register enum tree_code resultcode = code;
1819 /* Data type in which the computation is to be performed.
1820 In the simplest cases this is the common type of the arguments. */
1821 register tree result_type = NULL;
1823 /* Nonzero means operands have already been type-converted
1824 in whatever way is necessary.
1825 Zero means they need to be converted to RESULT_TYPE. */
1828 /* Nonzero means create the expression with this type, rather than
1830 tree build_type = 0;
1832 /* Nonzero means after finally constructing the expression
1833 convert it to this type. */
1834 tree final_type = 0;
1836 /* Nonzero if this is an operation like MIN or MAX which can
1837 safely be computed in short if both args are promoted shorts.
1838 Also implies COMMON.
1839 -1 indicates a bitwise operation; this makes a difference
1840 in the exact conditions for when it is safe to do the operation
1841 in a narrower mode. */
1844 /* Nonzero if this is a comparison operation;
1845 if both args are promoted shorts, compare the original shorts.
1846 Also implies COMMON. */
1847 int short_compare = 0;
1849 /* Nonzero if this is a right-shift operation, which can be computed on the
1850 original short and then promoted if the operand is a promoted short. */
1851 int short_shift = 0;
1853 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1858 op0 = default_conversion (orig_op0);
1859 op1 = default_conversion (orig_op1);
1867 type0 = TREE_TYPE (op0);
1868 type1 = TREE_TYPE (op1);
1870 /* The expression codes of the data types of the arguments tell us
1871 whether the arguments are integers, floating, pointers, etc. */
1872 code0 = TREE_CODE (type0);
1873 code1 = TREE_CODE (type1);
1875 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1876 STRIP_TYPE_NOPS (op0);
1877 STRIP_TYPE_NOPS (op1);
1879 /* If an error was already reported for one of the arguments,
1880 avoid reporting another error. */
1882 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
1883 return error_mark_node;
1888 /* Handle the pointer + int case. */
1889 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
1890 return pointer_int_sum (PLUS_EXPR, op0, op1);
1891 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
1892 return pointer_int_sum (PLUS_EXPR, op1, op0);
1898 /* Subtraction of two similar pointers.
1899 We must subtract them as integers, then divide by object size. */
1900 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
1901 && comp_target_types (type0, type1))
1902 return pointer_diff (op0, op1);
1903 /* Handle pointer minus int. Just like pointer plus int. */
1904 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
1905 return pointer_int_sum (MINUS_EXPR, op0, op1);
1914 case TRUNC_DIV_EXPR:
1916 case FLOOR_DIV_EXPR:
1917 case ROUND_DIV_EXPR:
1918 case EXACT_DIV_EXPR:
1919 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
1920 || code0 == COMPLEX_TYPE)
1921 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
1922 || code1 == COMPLEX_TYPE))
1924 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
1925 resultcode = RDIV_EXPR;
1928 /* Although it would be tempting to shorten always here, that
1929 loses on some targets, since the modulo instruction is
1930 undefined if the quotient can't be represented in the
1931 computation mode. We shorten only if unsigned or if
1932 dividing by something we know != -1. */
1933 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
1934 || (TREE_CODE (op1) == INTEGER_CST
1935 && (TREE_INT_CST_LOW (op1) != -1
1936 || TREE_INT_CST_HIGH (op1) != -1)));
1943 case BIT_ANDTC_EXPR:
1946 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
1948 /* If one operand is a constant, and the other is a short type
1949 that has been converted to an int,
1950 really do the work in the short type and then convert the
1951 result to int. If we are lucky, the constant will be 0 or 1
1952 in the short type, making the entire operation go away. */
1953 if (TREE_CODE (op0) == INTEGER_CST
1954 && TREE_CODE (op1) == NOP_EXPR
1955 && TYPE_PRECISION (type1) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))
1956 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0))))
1958 final_type = result_type;
1959 op1 = TREE_OPERAND (op1, 0);
1960 result_type = TREE_TYPE (op1);
1962 if (TREE_CODE (op1) == INTEGER_CST
1963 && TREE_CODE (op0) == NOP_EXPR
1964 && TYPE_PRECISION (type0) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))
1965 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
1967 final_type = result_type;
1968 op0 = TREE_OPERAND (op0, 0);
1969 result_type = TREE_TYPE (op0);
1973 case TRUNC_MOD_EXPR:
1974 case FLOOR_MOD_EXPR:
1975 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
1977 /* Although it would be tempting to shorten always here, that loses
1978 on some targets, since the modulo instruction is undefined if the
1979 quotient can't be represented in the computation mode. We shorten
1980 only if unsigned or if dividing by something we know != -1. */
1981 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
1982 || (TREE_CODE (op1) == INTEGER_CST
1983 && (TREE_INT_CST_LOW (op1) != -1
1984 || TREE_INT_CST_HIGH (op1) != -1)));
1989 case TRUTH_ANDIF_EXPR:
1990 case TRUTH_ORIF_EXPR:
1991 case TRUTH_AND_EXPR:
1993 case TRUTH_XOR_EXPR:
1994 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
1995 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
1996 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
1997 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
1999 /* Result of these operations is always an int,
2000 but that does not mean the operands should be
2001 converted to ints! */
2002 result_type = integer_type_node;
2003 op0 = truthvalue_conversion (op0);
2004 op1 = truthvalue_conversion (op1);
2009 /* Shift operations: result has same type as first operand;
2010 always convert second operand to int.
2011 Also set SHORT_SHIFT if shifting rightward. */
2014 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2016 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2018 if (tree_int_cst_sgn (op1) < 0)
2019 warning ("right shift count is negative");
2022 if (TREE_INT_CST_LOW (op1) | TREE_INT_CST_HIGH (op1))
2024 if (TREE_INT_CST_HIGH (op1) != 0
2025 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2026 >= TYPE_PRECISION (type0)))
2027 warning ("right shift count >= width of type");
2030 /* Use the type of the value to be shifted.
2031 This is what most traditional C compilers do. */
2032 result_type = type0;
2033 /* Unless traditional, convert the shift-count to an integer,
2034 regardless of size of value being shifted. */
2035 if (! flag_traditional)
2037 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2038 op1 = convert (integer_type_node, op1);
2039 /* Avoid converting op1 to result_type later. */
2046 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2048 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2050 if (tree_int_cst_sgn (op1) < 0)
2051 warning ("left shift count is negative");
2052 else if (TREE_INT_CST_HIGH (op1) != 0
2053 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2054 >= TYPE_PRECISION (type0)))
2055 warning ("left shift count >= width of type");
2057 /* Use the type of the value to be shifted.
2058 This is what most traditional C compilers do. */
2059 result_type = type0;
2060 /* Unless traditional, convert the shift-count to an integer,
2061 regardless of size of value being shifted. */
2062 if (! flag_traditional)
2064 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2065 op1 = convert (integer_type_node, op1);
2066 /* Avoid converting op1 to result_type later. */
2074 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2076 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2078 if (tree_int_cst_sgn (op1) < 0)
2079 warning ("shift count is negative");
2080 else if (TREE_INT_CST_HIGH (op1) != 0
2081 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1)
2082 >= TYPE_PRECISION (type0)))
2083 warning ("shift count >= width of type");
2085 /* Use the type of the value to be shifted.
2086 This is what most traditional C compilers do. */
2087 result_type = type0;
2088 /* Unless traditional, convert the shift-count to an integer,
2089 regardless of size of value being shifted. */
2090 if (! flag_traditional)
2092 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2093 op1 = convert (integer_type_node, op1);
2094 /* Avoid converting op1 to result_type later. */
2102 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
2103 warning ("comparing floating point with == or != is unsafe");
2104 /* Result of comparison is always int,
2105 but don't convert the args to int! */
2106 build_type = integer_type_node;
2107 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2108 || code0 == COMPLEX_TYPE)
2109 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2110 || code1 == COMPLEX_TYPE))
2112 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2114 register tree tt0 = TREE_TYPE (type0);
2115 register tree tt1 = TREE_TYPE (type1);
2116 /* Anything compares with void *. void * compares with anything.
2117 Otherwise, the targets must be compatible
2118 and both must be object or both incomplete. */
2119 if (comp_target_types (type0, type1))
2120 result_type = common_type (type0, type1);
2121 else if (TYPE_MAIN_VARIANT (tt0) == void_type_node)
2123 /* op0 != orig_op0 detects the case of something
2124 whose value is 0 but which isn't a valid null ptr const. */
2125 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
2126 && TREE_CODE (tt1) == FUNCTION_TYPE)
2127 pedwarn ("ANSI C forbids comparison of `void *' with function pointer");
2129 else if (TYPE_MAIN_VARIANT (tt1) == void_type_node)
2131 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
2132 && TREE_CODE (tt0) == FUNCTION_TYPE)
2133 pedwarn ("ANSI C forbids comparison of `void *' with function pointer");
2136 pedwarn ("comparison of distinct pointer types lacks a cast");
2138 if (result_type == NULL_TREE)
2139 result_type = ptr_type_node;
2141 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2142 && integer_zerop (op1))
2143 result_type = type0;
2144 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2145 && integer_zerop (op0))
2146 result_type = type1;
2147 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2149 result_type = type0;
2150 if (! flag_traditional)
2151 pedwarn ("comparison between pointer and integer");
2153 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2155 result_type = type1;
2156 if (! flag_traditional)
2157 pedwarn ("comparison between pointer and integer");
2163 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2164 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2166 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2168 if (comp_target_types (type0, type1))
2170 result_type = common_type (type0, type1);
2172 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2173 pedwarn ("ANSI C forbids ordered comparisons of pointers to functions");
2177 result_type = ptr_type_node;
2178 pedwarn ("comparison of distinct pointer types lacks a cast");
2187 build_type = integer_type_node;
2188 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2189 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2191 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2193 if (comp_target_types (type0, type1))
2195 result_type = common_type (type0, type1);
2196 if ((TYPE_SIZE (TREE_TYPE (type0)) != 0)
2197 != (TYPE_SIZE (TREE_TYPE (type1)) != 0))
2198 pedwarn ("comparison of complete and incomplete pointers");
2200 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2201 pedwarn ("ANSI C forbids ordered comparisons of pointers to functions");
2205 result_type = ptr_type_node;
2206 pedwarn ("comparison of distinct pointer types lacks a cast");
2209 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2210 && integer_zerop (op1))
2212 result_type = type0;
2213 if (pedantic || extra_warnings)
2214 pedwarn ("ordered comparison of pointer with integer zero");
2216 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2217 && integer_zerop (op0))
2219 result_type = type1;
2221 pedwarn ("ordered comparison of pointer with integer zero");
2223 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2225 result_type = type0;
2226 if (! flag_traditional)
2227 pedwarn ("comparison between pointer and integer");
2229 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2231 result_type = type1;
2232 if (! flag_traditional)
2233 pedwarn ("comparison between pointer and integer");
2241 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2243 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2245 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
2247 if (shorten || common || short_compare)
2248 result_type = common_type (type0, type1);
2250 /* For certain operations (which identify themselves by shorten != 0)
2251 if both args were extended from the same smaller type,
2252 do the arithmetic in that type and then extend.
2254 shorten !=0 and !=1 indicates a bitwise operation.
2255 For them, this optimization is safe only if
2256 both args are zero-extended or both are sign-extended.
2257 Otherwise, we might change the result.
2258 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2259 but calculated in (unsigned short) it would be (unsigned short)-1. */
2261 if (shorten && none_complex)
2263 int unsigned0, unsigned1;
2264 tree arg0 = get_narrower (op0, &unsigned0);
2265 tree arg1 = get_narrower (op1, &unsigned1);
2266 /* UNS is 1 if the operation to be done is an unsigned one. */
2267 int uns = TREE_UNSIGNED (result_type);
2270 final_type = result_type;
2272 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2273 but it *requires* conversion to FINAL_TYPE. */
2275 if ((TYPE_PRECISION (TREE_TYPE (op0))
2276 == TYPE_PRECISION (TREE_TYPE (arg0)))
2277 && TREE_TYPE (op0) != final_type)
2278 unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
2279 if ((TYPE_PRECISION (TREE_TYPE (op1))
2280 == TYPE_PRECISION (TREE_TYPE (arg1)))
2281 && TREE_TYPE (op1) != final_type)
2282 unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
2284 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2286 /* For bitwise operations, signedness of nominal type
2287 does not matter. Consider only how operands were extended. */
2291 /* Note that in all three cases below we refrain from optimizing
2292 an unsigned operation on sign-extended args.
2293 That would not be valid. */
2295 /* Both args variable: if both extended in same way
2296 from same width, do it in that width.
2297 Do it unsigned if args were zero-extended. */
2298 if ((TYPE_PRECISION (TREE_TYPE (arg0))
2299 < TYPE_PRECISION (result_type))
2300 && (TYPE_PRECISION (TREE_TYPE (arg1))
2301 == TYPE_PRECISION (TREE_TYPE (arg0)))
2302 && unsigned0 == unsigned1
2303 && (unsigned0 || !uns))
2305 = signed_or_unsigned_type (unsigned0,
2306 common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
2307 else if (TREE_CODE (arg0) == INTEGER_CST
2308 && (unsigned1 || !uns)
2309 && (TYPE_PRECISION (TREE_TYPE (arg1))
2310 < TYPE_PRECISION (result_type))
2311 && (type = signed_or_unsigned_type (unsigned1,
2313 int_fits_type_p (arg0, type)))
2315 else if (TREE_CODE (arg1) == INTEGER_CST
2316 && (unsigned0 || !uns)
2317 && (TYPE_PRECISION (TREE_TYPE (arg0))
2318 < TYPE_PRECISION (result_type))
2319 && (type = signed_or_unsigned_type (unsigned0,
2321 int_fits_type_p (arg1, type)))
2325 /* Shifts can be shortened if shifting right. */
2330 tree arg0 = get_narrower (op0, &unsigned_arg);
2332 final_type = result_type;
2334 if (arg0 == op0 && final_type == TREE_TYPE (op0))
2335 unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
2337 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
2338 /* We can shorten only if the shift count is less than the
2339 number of bits in the smaller type size. */
2340 && TREE_INT_CST_HIGH (op1) == 0
2341 && TYPE_PRECISION (TREE_TYPE (arg0)) > TREE_INT_CST_LOW (op1)
2342 /* If arg is sign-extended and then unsigned-shifted,
2343 we can simulate this with a signed shift in arg's type
2344 only if the extended result is at least twice as wide
2345 as the arg. Otherwise, the shift could use up all the
2346 ones made by sign-extension and bring in zeros.
2347 We can't optimize that case at all, but in most machines
2348 it never happens because available widths are 2**N. */
2349 && (!TREE_UNSIGNED (final_type)
2351 || 2 * TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (result_type)))
2353 /* Do an unsigned shift if the operand was zero-extended. */
2355 = signed_or_unsigned_type (unsigned_arg,
2357 /* Convert value-to-be-shifted to that type. */
2358 if (TREE_TYPE (op0) != result_type)
2359 op0 = convert (result_type, op0);
2364 /* Comparison operations are shortened too but differently.
2365 They identify themselves by setting short_compare = 1. */
2369 /* Don't write &op0, etc., because that would prevent op0
2370 from being kept in a register.
2371 Instead, make copies of the our local variables and
2372 pass the copies by reference, then copy them back afterward. */
2373 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
2374 enum tree_code xresultcode = resultcode;
2376 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
2379 op0 = xop0, op1 = xop1;
2381 resultcode = xresultcode;
2383 if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare != 0)
2384 && skip_evaluation == 0)
2386 int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0));
2387 int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1));
2389 int unsignedp0, unsignedp1;
2390 tree primop0 = get_narrower (op0, &unsignedp0);
2391 tree primop1 = get_narrower (op1, &unsignedp1);
2395 STRIP_TYPE_NOPS (xop0);
2396 STRIP_TYPE_NOPS (xop1);
2398 /* Give warnings for comparisons between signed and unsigned
2399 quantities that may fail. */
2400 /* Do the checking based on the original operand trees, so that
2401 casts will be considered, but default promotions won't be. */
2403 /* Do not warn if the comparison is being done in a signed type,
2404 since the signed type will only be chosen if it can represent
2405 all the values of the unsigned type. */
2406 if (! TREE_UNSIGNED (result_type))
2408 /* Do not warn if both operands are the same signedness. */
2409 else if (op0_signed == op1_signed)
2415 sop = xop0, uop = xop1;
2417 sop = xop1, uop = xop0;
2419 /* Do not warn if the signed quantity is an unsuffixed
2420 integer literal (or some static constant expression
2421 involving such literals) and it is non-negative. */
2422 if (TREE_CODE (sop) == INTEGER_CST
2423 && tree_int_cst_sgn (sop) >= 0)
2425 /* Do not warn if the comparison is an equality operation,
2426 the unsigned quantity is an integral constant, and it
2427 would fit in the result if the result were signed. */
2428 else if (TREE_CODE (uop) == INTEGER_CST
2429 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
2430 && int_fits_type_p (uop, signed_type (result_type)))
2432 /* Do not warn if the unsigned quantity is an enumeration
2433 constant and its maximum value would fit in the result
2434 if the result were signed. */
2435 else if (TREE_CODE (uop) == INTEGER_CST
2436 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
2437 && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE(uop)),
2438 signed_type (result_type)))
2441 warning ("comparison between signed and unsigned");
2444 /* Warn if two unsigned values are being compared in a size
2445 larger than their original size, and one (and only one) is the
2446 result of a `~' operator. This comparison will always fail.
2448 Also warn if one operand is a constant, and the constant
2449 does not have all bits set that are set in the ~ operand
2450 when it is extended. */
2452 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
2453 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
2455 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
2456 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
2459 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
2462 if (TREE_CODE (primop0) == INTEGER_CST
2463 || TREE_CODE (primop1) == INTEGER_CST)
2466 long constant, mask;
2467 int unsignedp, bits;
2469 if (TREE_CODE (primop0) == INTEGER_CST)
2472 unsignedp = unsignedp1;
2473 constant = TREE_INT_CST_LOW (primop0);
2478 unsignedp = unsignedp0;
2479 constant = TREE_INT_CST_LOW (primop1);
2482 bits = TYPE_PRECISION (TREE_TYPE (primop));
2483 if (bits < TYPE_PRECISION (result_type)
2484 && bits < HOST_BITS_PER_LONG && unsignedp)
2486 mask = (~0L) << bits;
2487 if ((mask & constant) != mask)
2488 warning ("comparison of promoted ~unsigned with constant");
2491 else if (unsignedp0 && unsignedp1
2492 && (TYPE_PRECISION (TREE_TYPE (primop0))
2493 < TYPE_PRECISION (result_type))
2494 && (TYPE_PRECISION (TREE_TYPE (primop1))
2495 < TYPE_PRECISION (result_type)))
2496 warning ("comparison of promoted ~unsigned with unsigned");
2502 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2503 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2504 Then the expression will be built.
2505 It will be given type FINAL_TYPE if that is nonzero;
2506 otherwise, it will be given type RESULT_TYPE. */
2510 binary_op_error (code);
2511 return error_mark_node;
2516 if (TREE_TYPE (op0) != result_type)
2517 op0 = convert (result_type, op0);
2518 if (TREE_TYPE (op1) != result_type)
2519 op1 = convert (result_type, op1);
2522 if (build_type == NULL_TREE)
2523 build_type = result_type;
2526 register tree result = build (resultcode, build_type, op0, op1);
2527 register tree folded;
2529 folded = fold (result);
2530 if (folded == result)
2531 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2532 if (final_type != 0)
2533 return convert (final_type, folded);
2538 /* Return a tree for the sum or difference (RESULTCODE says which)
2539 of pointer PTROP and integer INTOP. */
2542 pointer_int_sum (resultcode, ptrop, intop)
2543 enum tree_code resultcode;
2544 register tree ptrop, intop;
2548 register tree result;
2549 register tree folded;
2551 /* The result is a pointer of the same type that is being added. */
2553 register tree result_type = TREE_TYPE (ptrop);
2555 if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
2557 if (pedantic || warn_pointer_arith)
2558 pedwarn ("pointer of type `void *' used in arithmetic");
2559 size_exp = integer_one_node;
2561 else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
2563 if (pedantic || warn_pointer_arith)
2564 pedwarn ("pointer to a function used in arithmetic");
2565 size_exp = integer_one_node;
2568 size_exp = c_size_in_bytes (TREE_TYPE (result_type));
2570 /* If what we are about to multiply by the size of the elements
2571 contains a constant term, apply distributive law
2572 and multiply that constant term separately.
2573 This helps produce common subexpressions. */
2575 if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
2576 && ! TREE_CONSTANT (intop)
2577 && TREE_CONSTANT (TREE_OPERAND (intop, 1))
2578 && TREE_CONSTANT (size_exp)
2579 /* If the constant comes from pointer subtraction,
2580 skip this optimization--it would cause an error. */
2581 && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE
2582 /* If the constant is unsigned, and smaller than the pointer size,
2583 then we must skip this optimization. This is because it could cause
2584 an overflow error if the constant is negative but INTOP is not. */
2585 && (! TREE_UNSIGNED (TREE_TYPE (intop))
2586 || (TYPE_PRECISION (TREE_TYPE (intop))
2587 == TYPE_PRECISION (TREE_TYPE (ptrop)))))
2589 enum tree_code subcode = resultcode;
2590 tree int_type = TREE_TYPE (intop);
2591 if (TREE_CODE (intop) == MINUS_EXPR)
2592 subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
2593 /* Convert both subexpression types to the type of intop,
2594 because weird cases involving pointer arithmetic
2595 can result in a sum or difference with different type args. */
2596 ptrop = build_binary_op (subcode, ptrop,
2597 convert (int_type, TREE_OPERAND (intop, 1)), 1);
2598 intop = convert (int_type, TREE_OPERAND (intop, 0));
2601 /* Convert the integer argument to a type the same size as sizetype
2602 so the multiply won't overflow spuriously. */
2604 if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype)
2605 || TREE_UNSIGNED (TREE_TYPE (intop)) != TREE_UNSIGNED (sizetype))
2606 intop = convert (type_for_size (TYPE_PRECISION (sizetype),
2607 TREE_UNSIGNED (sizetype)), intop);
2609 /* Replace the integer argument with a suitable product by the object size.
2610 Do this multiplication as signed, then convert to the appropriate
2611 pointer type (actually unsigned integral). */
2613 intop = convert (result_type,
2614 build_binary_op (MULT_EXPR, intop,
2615 convert (TREE_TYPE (intop), size_exp), 1));
2617 /* Create the sum or difference. */
2619 result = build (resultcode, result_type, ptrop, intop);
2621 folded = fold (result);
2622 if (folded == result)
2623 TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop);
2627 /* Return a tree for the difference of pointers OP0 and OP1.
2628 The resulting tree has type int. */
2631 pointer_diff (op0, op1)
2632 register tree op0, op1;
2634 register tree result, folded;
2635 tree restype = ptrdiff_type_node;
2637 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2639 if (pedantic || warn_pointer_arith)
2641 if (TREE_CODE (target_type) == VOID_TYPE)
2642 pedwarn ("pointer of type `void *' used in subtraction");
2643 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2644 pedwarn ("pointer to a function used in subtraction");
2647 /* First do the subtraction as integers;
2648 then drop through to build the divide operator.
2649 Do not do default conversions on the minus operator
2650 in case restype is a short type. */
2652 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2653 convert (restype, op1), 0);
2654 /* This generates an error if op1 is pointer to incomplete type. */
2655 if (TYPE_SIZE (TREE_TYPE (TREE_TYPE (op1))) == 0)
2656 error ("arithmetic on pointer to an incomplete type");
2658 /* This generates an error if op0 is pointer to incomplete type. */
2659 op1 = c_size_in_bytes (target_type);
2661 /* Divide by the size, in easiest possible way. */
2663 result = build (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2665 folded = fold (result);
2666 if (folded == result)
2667 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2671 /* Construct and perhaps optimize a tree representation
2672 for a unary operation. CODE, a tree_code, specifies the operation
2673 and XARG is the operand. NOCONVERT nonzero suppresses
2674 the default promotions (such as from short to int). */
2677 build_unary_op (code, xarg, noconvert)
2678 enum tree_code code;
2682 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2683 register tree arg = xarg;
2684 register tree argtype = 0;
2685 register enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2688 if (typecode == ERROR_MARK)
2689 return error_mark_node;
2690 if (typecode == ENUMERAL_TYPE)
2691 typecode = INTEGER_TYPE;
2696 /* This is used for unary plus, because a CONVERT_EXPR
2697 is enough to prevent anybody from looking inside for
2698 associativity, but won't generate any code. */
2699 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2700 || typecode == COMPLEX_TYPE))
2702 error ("wrong type argument to unary plus");
2703 return error_mark_node;
2705 else if (!noconvert)
2706 arg = default_conversion (arg);
2710 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2711 || typecode == COMPLEX_TYPE))
2713 error ("wrong type argument to unary minus");
2714 return error_mark_node;
2716 else if (!noconvert)
2717 arg = default_conversion (arg);
2721 if (typecode == COMPLEX_TYPE)
2725 arg = default_conversion (arg);
2727 else if (typecode != INTEGER_TYPE)
2729 error ("wrong type argument to bit-complement");
2730 return error_mark_node;
2732 else if (!noconvert)
2733 arg = default_conversion (arg);
2737 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2738 || typecode == COMPLEX_TYPE))
2740 error ("wrong type argument to abs");
2741 return error_mark_node;
2743 else if (!noconvert)
2744 arg = default_conversion (arg);
2748 /* Conjugating a real value is a no-op, but allow it anyway. */
2749 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2750 || typecode == COMPLEX_TYPE))
2752 error ("wrong type argument to conjugation");
2753 return error_mark_node;
2755 else if (!noconvert)
2756 arg = default_conversion (arg);
2759 case TRUTH_NOT_EXPR:
2760 if (typecode != INTEGER_TYPE
2761 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2762 && typecode != COMPLEX_TYPE
2763 /* These will convert to a pointer. */
2764 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2766 error ("wrong type argument to unary exclamation mark");
2767 return error_mark_node;
2769 arg = truthvalue_conversion (arg);
2770 return invert_truthvalue (arg);
2776 if (TREE_CODE (arg) == COMPLEX_CST)
2777 return TREE_REALPART (arg);
2778 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2779 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2784 if (TREE_CODE (arg) == COMPLEX_CST)
2785 return TREE_IMAGPART (arg);
2786 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2787 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2789 return convert (TREE_TYPE (arg), integer_zero_node);
2791 case PREINCREMENT_EXPR:
2792 case POSTINCREMENT_EXPR:
2793 case PREDECREMENT_EXPR:
2794 case POSTDECREMENT_EXPR:
2795 /* Handle complex lvalues (when permitted)
2796 by reduction to simpler cases. */
2798 val = unary_complex_lvalue (code, arg);
2802 /* Increment or decrement the real part of the value,
2803 and don't change the imaginary part. */
2804 if (typecode == COMPLEX_TYPE)
2808 arg = stabilize_reference (arg);
2809 real = build_unary_op (REALPART_EXPR, arg, 1);
2810 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2811 return build (COMPLEX_EXPR, TREE_TYPE (arg),
2812 build_unary_op (code, real, 1), imag);
2815 /* Report invalid types. */
2817 if (typecode != POINTER_TYPE
2818 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2820 error ("wrong type argument to %s",
2821 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2822 ? "increment" : "decrement");
2823 return error_mark_node;
2828 tree result_type = TREE_TYPE (arg);
2830 arg = get_unwidened (arg, 0);
2831 argtype = TREE_TYPE (arg);
2833 /* Compute the increment. */
2835 if (typecode == POINTER_TYPE)
2837 /* If pointer target is an undefined struct,
2838 we just cannot know how to do the arithmetic. */
2839 if (TYPE_SIZE (TREE_TYPE (result_type)) == 0)
2840 error ("%s of pointer to unknown structure",
2841 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2842 ? "increment" : "decrement");
2843 else if ((pedantic || warn_pointer_arith)
2844 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2845 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2846 pedwarn ("wrong type argument to %s",
2847 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2848 ? "increment" : "decrement");
2849 inc = c_size_in_bytes (TREE_TYPE (result_type));
2852 inc = integer_one_node;
2854 inc = convert (argtype, inc);
2856 /* Handle incrementing a cast-expression. */
2859 switch (TREE_CODE (arg))
2864 case FIX_TRUNC_EXPR:
2865 case FIX_FLOOR_EXPR:
2866 case FIX_ROUND_EXPR:
2868 pedantic_lvalue_warning (CONVERT_EXPR);
2869 /* If the real type has the same machine representation
2870 as the type it is cast to, we can make better output
2871 by adding directly to the inside of the cast. */
2872 if ((TREE_CODE (TREE_TYPE (arg))
2873 == TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0))))
2874 && (TYPE_MODE (TREE_TYPE (arg))
2875 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (arg, 0)))))
2876 arg = TREE_OPERAND (arg, 0);
2879 tree incremented, modify, value;
2880 arg = stabilize_reference (arg);
2881 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
2884 value = save_expr (arg);
2885 incremented = build (((code == PREINCREMENT_EXPR
2886 || code == POSTINCREMENT_EXPR)
2887 ? PLUS_EXPR : MINUS_EXPR),
2888 argtype, value, inc);
2889 TREE_SIDE_EFFECTS (incremented) = 1;
2890 modify = build_modify_expr (arg, NOP_EXPR, incremented);
2891 value = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
2892 TREE_USED (value) = 1;
2902 /* Complain about anything else that is not a true lvalue. */
2903 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2904 || code == POSTINCREMENT_EXPR)
2905 ? "invalid lvalue in increment"
2906 : "invalid lvalue in decrement")))
2907 return error_mark_node;
2909 /* Report a read-only lvalue. */
2910 if (TREE_READONLY (arg))
2911 readonly_warning (arg,
2912 ((code == PREINCREMENT_EXPR
2913 || code == POSTINCREMENT_EXPR)
2914 ? "increment" : "decrement"));
2916 val = build (code, TREE_TYPE (arg), arg, inc);
2917 TREE_SIDE_EFFECTS (val) = 1;
2918 val = convert (result_type, val);
2919 if (TREE_CODE (val) != code)
2920 TREE_NO_UNUSED_WARNING (val) = 1;
2925 /* Note that this operation never does default_conversion
2926 regardless of NOCONVERT. */
2928 /* Let &* cancel out to simplify resulting code. */
2929 if (TREE_CODE (arg) == INDIRECT_REF)
2931 /* Don't let this be an lvalue. */
2932 if (lvalue_p (TREE_OPERAND (arg, 0)))
2933 return non_lvalue (TREE_OPERAND (arg, 0));
2934 return TREE_OPERAND (arg, 0);
2937 /* For &x[y], return x+y */
2938 if (TREE_CODE (arg) == ARRAY_REF)
2940 if (mark_addressable (TREE_OPERAND (arg, 0)) == 0)
2941 return error_mark_node;
2942 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
2943 TREE_OPERAND (arg, 1), 1);
2946 /* Handle complex lvalues (when permitted)
2947 by reduction to simpler cases. */
2948 val = unary_complex_lvalue (code, arg);
2952 #if 0 /* Turned off because inconsistent;
2953 float f; *&(int)f = 3.4 stores in int format
2954 whereas (int)f = 3.4 stores in float format. */
2955 /* Address of a cast is just a cast of the address
2956 of the operand of the cast. */
2957 switch (TREE_CODE (arg))
2962 case FIX_TRUNC_EXPR:
2963 case FIX_FLOOR_EXPR:
2964 case FIX_ROUND_EXPR:
2967 pedwarn ("ANSI C forbids the address of a cast expression");
2968 return convert (build_pointer_type (TREE_TYPE (arg)),
2969 build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0),
2974 /* Allow the address of a constructor if all the elements
2976 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_CONSTANT (arg))
2978 /* Anything not already handled and not a true memory reference
2980 else if (typecode != FUNCTION_TYPE
2981 && !lvalue_or_else (arg, "invalid lvalue in unary `&'"))
2982 return error_mark_node;
2984 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
2985 argtype = TREE_TYPE (arg);
2986 /* If the lvalue is const or volatile, merge that into the type
2987 to which the address will point. Note that you can't get a
2988 restricted pointer by taking the address of something, so we
2989 only have to deal with `const' and `volatile' here. */
2990 if (TREE_CODE_CLASS (TREE_CODE (arg)) == 'd'
2991 || TREE_CODE_CLASS (TREE_CODE (arg)) == 'r')
2993 if (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg))
2994 argtype = c_build_type_variant (argtype,
2995 TREE_READONLY (arg),
2996 TREE_THIS_VOLATILE (arg));
2999 argtype = build_pointer_type (argtype);
3001 if (mark_addressable (arg) == 0)
3002 return error_mark_node;
3007 if (TREE_CODE (arg) == COMPONENT_REF)
3009 tree field = TREE_OPERAND (arg, 1);
3011 addr = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
3013 if (DECL_C_BIT_FIELD (field))
3015 error ("attempt to take address of bit-field structure member `%s'",
3016 IDENTIFIER_POINTER (DECL_NAME (field)));
3017 return error_mark_node;
3020 addr = convert (argtype, addr);
3022 if (! integer_zerop (DECL_FIELD_BITPOS (field)))
3025 = size_binop (EASY_DIV_EXPR, DECL_FIELD_BITPOS (field),
3026 size_int (BITS_PER_UNIT));
3027 int flag = TREE_CONSTANT (addr);
3028 addr = fold (build (PLUS_EXPR, argtype,
3029 addr, convert (argtype, offset)));
3030 TREE_CONSTANT (addr) = flag;
3034 addr = build1 (code, argtype, arg);
3036 /* Address of a static or external variable or
3037 file-scope function counts as a constant. */
3039 && ! (TREE_CODE (arg) == FUNCTION_DECL
3040 && DECL_CONTEXT (arg) != 0))
3041 TREE_CONSTANT (addr) = 1;
3050 argtype = TREE_TYPE (arg);
3051 return fold (build1 (code, argtype, arg));
3055 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3056 convert ARG with the same conversions in the same order
3057 and return the result. */
3060 convert_sequence (conversions, arg)
3064 switch (TREE_CODE (conversions))
3069 case FIX_TRUNC_EXPR:
3070 case FIX_FLOOR_EXPR:
3071 case FIX_ROUND_EXPR:
3073 return convert (TREE_TYPE (conversions),
3074 convert_sequence (TREE_OPERAND (conversions, 0),
3083 /* Return nonzero if REF is an lvalue valid for this language.
3084 Lvalues can be assigned, unless their type has TYPE_READONLY.
3085 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3091 register enum tree_code code = TREE_CODE (ref);
3098 return lvalue_p (TREE_OPERAND (ref, 0));
3109 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3110 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3114 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3121 /* Return nonzero if REF is an lvalue valid for this language;
3122 otherwise, print an error message and return zero. */
3125 lvalue_or_else (ref, msgid)
3129 int win = lvalue_p (ref);
3132 error ("%s", msgid);
3137 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3138 for certain kinds of expressions which are not really lvalues
3139 but which we can accept as lvalues.
3141 If ARG is not a kind of expression we can handle, return zero. */
3144 unary_complex_lvalue (code, arg)
3145 enum tree_code code;
3148 /* Handle (a, b) used as an "lvalue". */
3149 if (TREE_CODE (arg) == COMPOUND_EXPR)
3151 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
3153 /* If this returns a function type, it isn't really being used as
3154 an lvalue, so don't issue a warning about it. */
3155 if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE)
3156 pedantic_lvalue_warning (COMPOUND_EXPR);
3158 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
3159 TREE_OPERAND (arg, 0), real_result);
3162 /* Handle (a ? b : c) used as an "lvalue". */
3163 if (TREE_CODE (arg) == COND_EXPR)
3165 pedantic_lvalue_warning (COND_EXPR);
3166 if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE)
3167 pedantic_lvalue_warning (COMPOUND_EXPR);
3169 return (build_conditional_expr
3170 (TREE_OPERAND (arg, 0),
3171 build_unary_op (code, TREE_OPERAND (arg, 1), 0),
3172 build_unary_op (code, TREE_OPERAND (arg, 2), 0)));
3178 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3179 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3182 pedantic_lvalue_warning (code)
3183 enum tree_code code;
3189 pedwarn ("ANSI C forbids use of conditional expressions as lvalues");
3192 pedwarn ("ANSI C forbids use of compound expressions as lvalues");
3195 pedwarn ("ANSI C forbids use of cast expressions as lvalues");
3200 /* Warn about storing in something that is `const'. */
3203 readonly_warning (arg, msgid)
3207 /* Forbid assignments to iterators. */
3208 if (TREE_CODE (arg) == VAR_DECL && ITERATOR_P (arg))
3209 pedwarn ("%s of iterator `%s'", _(msgid),
3210 IDENTIFIER_POINTER (DECL_NAME (arg)));
3212 if (TREE_CODE (arg) == COMPONENT_REF)
3214 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3215 readonly_warning (TREE_OPERAND (arg, 0), msgid);
3217 pedwarn ("%s of read-only member `%s'", _(msgid),
3218 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1))));
3220 else if (TREE_CODE (arg) == VAR_DECL)
3221 pedwarn ("%s of read-only variable `%s'", _(msgid),
3222 IDENTIFIER_POINTER (DECL_NAME (arg)));
3224 pedwarn ("%s of read-only location", _(msgid));
3227 /* Mark EXP saying that we need to be able to take the
3228 address of it; it should not be allocated in a register.
3229 Value is 1 if successful. */
3232 mark_addressable (exp)
3235 register tree x = exp;
3237 switch (TREE_CODE (x))
3240 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3242 error ("cannot take address of bitfield `%s'",
3243 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (x, 1))));
3247 /* ... fall through ... */
3253 x = TREE_OPERAND (x, 0);
3257 TREE_ADDRESSABLE (x) = 1;
3264 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
3265 && DECL_NONLOCAL (x))
3267 if (TREE_PUBLIC (x))
3269 error ("global register variable `%s' used in nested function",
3270 IDENTIFIER_POINTER (DECL_NAME (x)));
3273 pedwarn ("register variable `%s' used in nested function",
3274 IDENTIFIER_POINTER (DECL_NAME (x)));
3276 else if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x))
3278 if (TREE_PUBLIC (x))
3280 error ("address of global register variable `%s' requested",
3281 IDENTIFIER_POINTER (DECL_NAME (x)));
3285 /* If we are making this addressable due to its having
3286 volatile components, give a different error message. Also
3287 handle the case of an unnamed parameter by not trying
3288 to give the name. */
3290 else if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (x)))
3292 error ("cannot put object with volatile field into register");
3296 pedwarn ("address of register variable `%s' requested",
3297 IDENTIFIER_POINTER (DECL_NAME (x)));
3299 put_var_into_stack (x);
3303 TREE_ADDRESSABLE (x) = 1;
3304 #if 0 /* poplevel deals with this now. */
3305 if (DECL_CONTEXT (x) == 0)
3306 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
3314 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3317 build_conditional_expr (ifexp, op1, op2)
3318 tree ifexp, op1, op2;
3320 register tree type1;
3321 register tree type2;
3322 register enum tree_code code1;
3323 register enum tree_code code2;
3324 register tree result_type = NULL;
3325 tree orig_op1 = op1, orig_op2 = op2;
3327 ifexp = truthvalue_conversion (default_conversion (ifexp));
3329 #if 0 /* Produces wrong result if within sizeof. */
3330 /* Don't promote the operands separately if they promote
3331 the same way. Return the unpromoted type and let the combined
3332 value get promoted if necessary. */
3334 if (TREE_TYPE (op1) == TREE_TYPE (op2)
3335 && TREE_CODE (TREE_TYPE (op1)) != ARRAY_TYPE
3336 && TREE_CODE (TREE_TYPE (op1)) != ENUMERAL_TYPE
3337 && TREE_CODE (TREE_TYPE (op1)) != FUNCTION_TYPE)
3339 if (TREE_CODE (ifexp) == INTEGER_CST)
3340 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3342 return fold (build (COND_EXPR, TREE_TYPE (op1), ifexp, op1, op2));
3346 /* Promote both alternatives. */
3348 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3349 op1 = default_conversion (op1);
3350 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3351 op2 = default_conversion (op2);
3353 if (TREE_CODE (ifexp) == ERROR_MARK
3354 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3355 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3356 return error_mark_node;
3358 type1 = TREE_TYPE (op1);
3359 code1 = TREE_CODE (type1);
3360 type2 = TREE_TYPE (op2);
3361 code2 = TREE_CODE (type2);
3363 /* Quickly detect the usual case where op1 and op2 have the same type
3365 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3368 result_type = type1;
3370 result_type = TYPE_MAIN_VARIANT (type1);
3372 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE)
3373 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE))
3375 result_type = common_type (type1, type2);
3377 /* If -Wsign-compare, warn here if type1 and type2 have
3378 different signedness. We'll promote the signed to unsigned
3379 and later code won't know it used to be different.
3380 Do this check on the original types, so that explicit casts
3381 will be considered, but default promotions won't. */
3382 if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare)
3383 && !skip_evaluation)
3385 int unsigned_op1 = TREE_UNSIGNED (TREE_TYPE (orig_op1));
3386 int unsigned_op2 = TREE_UNSIGNED (TREE_TYPE (orig_op2));
3388 if (unsigned_op1 ^ unsigned_op2)
3390 /* Do not warn if the result type is signed, since the
3391 signed type will only be chosen if it can represent
3392 all the values of the unsigned type. */
3393 if (! TREE_UNSIGNED (result_type))
3395 /* Do not warn if the signed quantity is an unsuffixed
3396 integer literal (or some static constant expression
3397 involving such literals) and it is non-negative. */
3398 else if ((unsigned_op2 && TREE_CODE (op1) == INTEGER_CST
3399 && tree_int_cst_sgn (op1) >= 0)
3400 || (unsigned_op1 && TREE_CODE (op2) == INTEGER_CST
3401 && tree_int_cst_sgn (op2) >= 0))
3404 warning ("signed and unsigned type in conditional expression");
3408 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3410 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3411 pedwarn ("ANSI C forbids conditional expr with only one void side");
3412 result_type = void_type_node;
3414 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3416 if (comp_target_types (type1, type2))
3417 result_type = common_type (type1, type2);
3418 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
3419 && TREE_CODE (orig_op1) != NOP_EXPR)
3420 result_type = qualify_type (type2, type1);
3421 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
3422 && TREE_CODE (orig_op2) != NOP_EXPR)
3423 result_type = qualify_type (type1, type2);
3424 else if (TYPE_MAIN_VARIANT (TREE_TYPE (type1)) == void_type_node)
3426 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3427 pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer");
3428 result_type = qualify_type (type1, type2);
3430 else if (TYPE_MAIN_VARIANT (TREE_TYPE (type2)) == void_type_node)
3432 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3433 pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer");
3434 result_type = qualify_type (type2, type1);
3438 pedwarn ("pointer type mismatch in conditional expression");
3439 result_type = build_pointer_type (void_type_node);
3442 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3444 if (! integer_zerop (op2))
3445 pedwarn ("pointer/integer type mismatch in conditional expression");
3448 op2 = null_pointer_node;
3449 #if 0 /* The spec seems to say this is permitted. */
3450 if (pedantic && TREE_CODE (type1) == FUNCTION_TYPE)
3451 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3454 result_type = type1;
3456 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3458 if (!integer_zerop (op1))
3459 pedwarn ("pointer/integer type mismatch in conditional expression");
3462 op1 = null_pointer_node;
3463 #if 0 /* The spec seems to say this is permitted. */
3464 if (pedantic && TREE_CODE (type2) == FUNCTION_TYPE)
3465 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3468 result_type = type2;
3473 if (flag_cond_mismatch)
3474 result_type = void_type_node;
3477 error ("type mismatch in conditional expression");
3478 return error_mark_node;
3482 /* Merge const and volatile flags of the incoming types. */
3484 = build_type_variant (result_type,
3485 TREE_READONLY (op1) || TREE_READONLY (op2),
3486 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3488 if (result_type != TREE_TYPE (op1))
3489 op1 = convert_and_check (result_type, op1);
3490 if (result_type != TREE_TYPE (op2))
3491 op2 = convert_and_check (result_type, op2);
3494 if (code1 == RECORD_TYPE || code1 == UNION_TYPE)
3496 result_type = TREE_TYPE (op1);
3497 if (TREE_CONSTANT (ifexp))
3498 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3500 if (TYPE_MODE (result_type) == BLKmode)
3502 register tree tempvar
3503 = build_decl (VAR_DECL, NULL_TREE, result_type);
3504 register tree xop1 = build_modify_expr (tempvar, op1);
3505 register tree xop2 = build_modify_expr (tempvar, op2);
3506 register tree result = fold (build (COND_EXPR, result_type,
3507 ifexp, xop1, xop2));
3509 layout_decl (tempvar, TYPE_ALIGN (result_type));
3510 /* No way to handle variable-sized objects here.
3511 I fear that the entire handling of BLKmode conditional exprs
3512 needs to be redone. */
3513 if (TREE_CODE (DECL_SIZE (tempvar)) != INTEGER_CST)
3516 = assign_stack_local (DECL_MODE (tempvar),
3517 (TREE_INT_CST_LOW (DECL_SIZE (tempvar))
3518 + BITS_PER_UNIT - 1)
3522 TREE_SIDE_EFFECTS (result)
3523 = TREE_SIDE_EFFECTS (ifexp) | TREE_SIDE_EFFECTS (op1)
3524 | TREE_SIDE_EFFECTS (op2);
3525 return build (COMPOUND_EXPR, result_type, result, tempvar);
3530 if (TREE_CODE (ifexp) == INTEGER_CST)
3531 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3533 return fold (build (COND_EXPR, result_type, ifexp, op1, op2));
3536 /* Given a list of expressions, return a compound expression
3537 that performs them all and returns the value of the last of them. */
3540 build_compound_expr (list)
3543 return internal_build_compound_expr (list, TRUE);
3547 internal_build_compound_expr (list, first_p)
3553 if (TREE_CHAIN (list) == 0)
3555 #if 0 /* If something inside inhibited lvalueness, we should not override. */
3556 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3558 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3559 if (TREE_CODE (list) == NON_LVALUE_EXPR)
3560 list = TREE_OPERAND (list, 0);
3563 /* Don't let (0, 0) be null pointer constant. */
3564 if (!first_p && integer_zerop (TREE_VALUE (list)))
3565 return non_lvalue (TREE_VALUE (list));
3566 return TREE_VALUE (list);
3569 if (TREE_CHAIN (list) != 0 && TREE_CHAIN (TREE_CHAIN (list)) == 0)
3571 /* Convert arrays to pointers when there really is a comma operator. */
3572 if (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (list)))) == ARRAY_TYPE)
3573 TREE_VALUE (TREE_CHAIN (list))
3574 = default_conversion (TREE_VALUE (TREE_CHAIN (list)));
3577 rest = internal_build_compound_expr (TREE_CHAIN (list), FALSE);
3579 if (! TREE_SIDE_EFFECTS (TREE_VALUE (list)))
3581 /* The left-hand operand of a comma expression is like an expression
3582 statement: with -W or -Wunused, we should warn if it doesn't have
3583 any side-effects, unless it was explicitly cast to (void). */
3584 if ((extra_warnings || warn_unused)
3585 && ! (TREE_CODE (TREE_VALUE (list)) == CONVERT_EXPR
3586 && TREE_TYPE (TREE_VALUE (list)) == void_type_node))
3587 warning ("left-hand operand of comma expression has no effect");
3589 /* When pedantic, a compound expression can be neither an lvalue
3590 nor an integer constant expression. */
3595 /* With -Wunused, we should also warn if the left-hand operand does have
3596 side-effects, but computes a value which is not used. For example, in
3597 `foo() + bar(), baz()' the result of the `+' operator is not used,
3598 so we should issue a warning. */
3599 else if (warn_unused)
3600 warn_if_unused_value (TREE_VALUE (list));
3602 return build (COMPOUND_EXPR, TREE_TYPE (rest), TREE_VALUE (list), rest);
3605 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3608 build_c_cast (type, expr)
3612 register tree value = expr;
3614 if (type == error_mark_node || expr == error_mark_node)
3615 return error_mark_node;
3616 type = TYPE_MAIN_VARIANT (type);
3619 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3620 if (TREE_CODE (value) == NON_LVALUE_EXPR)
3621 value = TREE_OPERAND (value, 0);
3624 if (TREE_CODE (type) == ARRAY_TYPE)
3626 error ("cast specifies array type");
3627 return error_mark_node;
3630 if (TREE_CODE (type) == FUNCTION_TYPE)
3632 error ("cast specifies function type");
3633 return error_mark_node;
3636 if (type == TREE_TYPE (value))
3640 if (TREE_CODE (type) == RECORD_TYPE
3641 || TREE_CODE (type) == UNION_TYPE)
3642 pedwarn ("ANSI C forbids casting nonscalar to the same type");
3645 else if (TREE_CODE (type) == UNION_TYPE)
3648 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
3649 || TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE)
3650 value = default_conversion (value);
3652 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3653 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3654 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3663 pedwarn ("ANSI C forbids casts to union type");
3664 if (TYPE_NAME (type) != 0)
3666 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
3667 name = IDENTIFIER_POINTER (TYPE_NAME (type));
3669 name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));
3673 t = digest_init (type, build (CONSTRUCTOR, type, NULL_TREE,
3674 build_tree_list (field, value)),
3676 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3679 error ("cast to union type from type not present in union");
3680 return error_mark_node;
3686 /* If casting to void, avoid the error that would come
3687 from default_conversion in the case of a non-lvalue array. */
3688 if (type == void_type_node)
3689 return build1 (CONVERT_EXPR, type, value);
3691 /* Convert functions and arrays to pointers,
3692 but don't convert any other types. */
3693 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
3694 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE)
3695 value = default_conversion (value);
3696 otype = TREE_TYPE (value);
3698 /* Optionally warn about potentially worrisome casts. */
3701 && TREE_CODE (type) == POINTER_TYPE
3702 && TREE_CODE (otype) == POINTER_TYPE)
3704 /* Go to the innermost object being pointed to. */
3705 tree in_type = type;
3706 tree in_otype = otype;
3708 while (TREE_CODE (in_type) == POINTER_TYPE)
3709 in_type = TREE_TYPE (in_type);
3710 while (TREE_CODE (in_otype) == POINTER_TYPE)
3711 in_otype = TREE_TYPE (in_otype);
3713 if (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type))
3714 /* There are qualifiers present in IN_OTYPE that are not
3715 present in IN_TYPE. */
3716 pedwarn ("cast discards qualifiers from pointer target type");
3719 /* Warn about possible alignment problems. */
3720 if (STRICT_ALIGNMENT && warn_cast_align
3721 && TREE_CODE (type) == POINTER_TYPE
3722 && TREE_CODE (otype) == POINTER_TYPE
3723 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3724 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3725 /* Don't warn about opaque types, where the actual alignment
3726 restriction is unknown. */
3727 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3728 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3729 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3730 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3731 warning ("cast increases required alignment of target type");
3733 if (TREE_CODE (type) == INTEGER_TYPE
3734 && TREE_CODE (otype) == POINTER_TYPE
3735 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3736 && !TREE_CONSTANT (value))
3737 warning ("cast from pointer to integer of different size");
3739 if (warn_bad_function_cast
3740 && TREE_CODE (value) == CALL_EXPR
3741 && TREE_CODE (type) != TREE_CODE (otype))
3742 warning ("cast does not match function type");
3744 if (TREE_CODE (type) == POINTER_TYPE
3745 && TREE_CODE (otype) == INTEGER_TYPE
3746 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3748 /* Don't warn about converting 0 to pointer,
3749 provided the 0 was explicit--not cast or made by folding. */
3750 && !(TREE_CODE (value) == INTEGER_CST && integer_zerop (value))
3752 /* Don't warn about converting any constant. */
3753 && !TREE_CONSTANT (value))
3754 warning ("cast to pointer from integer of different size");
3757 value = convert (type, value);
3759 /* Ignore any integer overflow caused by the cast. */
3760 if (TREE_CODE (value) == INTEGER_CST)
3762 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3763 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3767 /* Pedantically, don't ley (void *) (FOO *) 0 be a null pointer constant. */
3768 if (pedantic && TREE_CODE (value) == INTEGER_CST
3769 && TREE_CODE (expr) == INTEGER_CST
3770 && TREE_CODE (TREE_TYPE (expr)) != INTEGER_TYPE)
3771 value = non_lvalue (value);
3773 /* If pedantic, don't let a cast be an lvalue. */
3774 if (value == expr && pedantic)
3775 value = non_lvalue (value);
3780 /* Build an assignment expression of lvalue LHS from value RHS.
3781 MODIFYCODE is the code for a binary operator that we use
3782 to combine the old value of LHS with RHS to get the new value.
3783 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3786 build_modify_expr (lhs, modifycode, rhs)
3788 enum tree_code modifycode;
3790 register tree result;
3792 tree lhstype = TREE_TYPE (lhs);
3793 tree olhstype = lhstype;
3795 /* Types that aren't fully specified cannot be used in assignments. */
3796 lhs = require_complete_type (lhs);
3798 /* Avoid duplicate error messages from operands that had errors. */
3799 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3800 return error_mark_node;
3802 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3803 /* Do not use STRIP_NOPS here. We do not want an enumerator
3804 whose value is 0 to count as a null pointer constant. */
3805 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3806 rhs = TREE_OPERAND (rhs, 0);
3810 /* Handle control structure constructs used as "lvalues". */
3812 switch (TREE_CODE (lhs))
3814 /* Handle (a, b) used as an "lvalue". */
3816 pedantic_lvalue_warning (COMPOUND_EXPR);
3817 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1), modifycode, rhs);
3818 if (TREE_CODE (newrhs) == ERROR_MARK)
3819 return error_mark_node;
3820 return build (COMPOUND_EXPR, lhstype,
3821 TREE_OPERAND (lhs, 0), newrhs);
3823 /* Handle (a ? b : c) used as an "lvalue". */
3825 pedantic_lvalue_warning (COND_EXPR);
3826 rhs = save_expr (rhs);
3828 /* Produce (a ? (b = rhs) : (c = rhs))
3829 except that the RHS goes through a save-expr
3830 so the code to compute it is only emitted once. */
3832 = build_conditional_expr (TREE_OPERAND (lhs, 0),
3833 build_modify_expr (TREE_OPERAND (lhs, 1),
3835 build_modify_expr (TREE_OPERAND (lhs, 2),
3837 if (TREE_CODE (cond) == ERROR_MARK)
3839 /* Make sure the code to compute the rhs comes out
3840 before the split. */
3841 return build (COMPOUND_EXPR, TREE_TYPE (lhs),
3842 /* But cast it to void to avoid an "unused" error. */
3843 convert (void_type_node, rhs), cond);
3849 /* If a binary op has been requested, combine the old LHS value with the RHS
3850 producing the value we should actually store into the LHS. */
3852 if (modifycode != NOP_EXPR)
3854 lhs = stabilize_reference (lhs);
3855 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3858 /* Handle a cast used as an "lvalue".
3859 We have already performed any binary operator using the value as cast.
3860 Now convert the result to the cast type of the lhs,
3861 and then true type of the lhs and store it there;
3862 then convert result back to the cast type to be the value
3863 of the assignment. */
3865 switch (TREE_CODE (lhs))
3870 case FIX_TRUNC_EXPR:
3871 case FIX_FLOOR_EXPR:
3872 case FIX_ROUND_EXPR:
3874 if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
3875 || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE)
3876 newrhs = default_conversion (newrhs);
3878 tree inner_lhs = TREE_OPERAND (lhs, 0);
3880 result = build_modify_expr (inner_lhs, NOP_EXPR,
3881 convert (TREE_TYPE (inner_lhs),
3882 convert (lhstype, newrhs)));
3883 if (TREE_CODE (result) == ERROR_MARK)
3885 pedantic_lvalue_warning (CONVERT_EXPR);
3886 return convert (TREE_TYPE (lhs), result);
3893 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3894 Reject anything strange now. */
3896 if (!lvalue_or_else (lhs, "invalid lvalue in assignment"))
3897 return error_mark_node;
3899 /* Warn about storing in something that is `const'. */
3901 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3902 || ((TREE_CODE (lhstype) == RECORD_TYPE
3903 || TREE_CODE (lhstype) == UNION_TYPE)
3904 && C_TYPE_FIELDS_READONLY (lhstype)))
3905 readonly_warning (lhs, "assignment");
3907 /* If storing into a structure or union member,
3908 it has probably been given type `int'.
3909 Compute the type that would go with
3910 the actual amount of storage the member occupies. */
3912 if (TREE_CODE (lhs) == COMPONENT_REF
3913 && (TREE_CODE (lhstype) == INTEGER_TYPE
3914 || TREE_CODE (lhstype) == REAL_TYPE
3915 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3916 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3918 /* If storing in a field that is in actuality a short or narrower than one,
3919 we must store in the field in its actual type. */
3921 if (lhstype != TREE_TYPE (lhs))
3923 lhs = copy_node (lhs);
3924 TREE_TYPE (lhs) = lhstype;
3927 /* Convert new value to destination type. */
3929 newrhs = convert_for_assignment (lhstype, newrhs, _("assignment"),
3930 NULL_TREE, NULL_TREE, 0);
3931 if (TREE_CODE (newrhs) == ERROR_MARK)
3932 return error_mark_node;
3934 result = build (MODIFY_EXPR, lhstype, lhs, newrhs);
3935 TREE_SIDE_EFFECTS (result) = 1;
3937 /* If we got the LHS in a different type for storing in,
3938 convert the result back to the nominal type of LHS
3939 so that the value we return always has the same type
3940 as the LHS argument. */
3942 if (olhstype == TREE_TYPE (result))
3944 return convert_for_assignment (olhstype, result, _("assignment"),
3945 NULL_TREE, NULL_TREE, 0);
3948 /* Convert value RHS to type TYPE as preparation for an assignment
3949 to an lvalue of type TYPE.
3950 The real work of conversion is done by `convert'.
3951 The purpose of this function is to generate error messages
3952 for assignments that are not allowed in C.
3953 ERRTYPE is a string to use in error messages:
3954 "assignment", "return", etc. If it is null, this is parameter passing
3955 for a function call (and different error messages are output).
3957 FUNNAME is the name of the function being called,
3958 as an IDENTIFIER_NODE, or null.
3959 PARMNUM is the number of the argument, for printing in error messages. */
3962 convert_for_assignment (type, rhs, errtype, fundecl, funname, parmnum)
3964 const char *errtype;
3965 tree fundecl, funname;
3968 register enum tree_code codel = TREE_CODE (type);
3969 register tree rhstype;
3970 register enum tree_code coder;
3972 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3973 /* Do not use STRIP_NOPS here. We do not want an enumerator
3974 whose value is 0 to count as a null pointer constant. */
3975 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3976 rhs = TREE_OPERAND (rhs, 0);
3978 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
3979 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
3980 rhs = default_conversion (rhs);
3981 else if (optimize && TREE_CODE (rhs) == VAR_DECL)
3982 rhs = decl_constant_value (rhs);
3984 rhstype = TREE_TYPE (rhs);
3985 coder = TREE_CODE (rhstype);
3987 if (coder == ERROR_MARK)
3988 return error_mark_node;
3990 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3992 overflow_warning (rhs);
3993 /* Check for Objective-C protocols. This will issue a warning if
3994 there are protocol violations. No need to use the return value. */
3995 maybe_objc_comptypes (type, rhstype, 0);
3999 if (coder == VOID_TYPE)
4001 error ("void value not ignored as it ought to be");
4002 return error_mark_node;
4004 /* Arithmetic types all interconvert, and enum is treated like int. */
4005 if ((codel == INTEGER_TYPE || codel == REAL_TYPE || codel == ENUMERAL_TYPE
4006 || codel == COMPLEX_TYPE)
4007 && (coder == INTEGER_TYPE || coder == REAL_TYPE || coder == ENUMERAL_TYPE
4008 || coder == COMPLEX_TYPE))
4009 return convert_and_check (type, rhs);
4011 /* Conversion to a transparent union from its member types.
4012 This applies only to function arguments. */
4013 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type) && ! errtype)
4016 tree marginal_memb_type = 0;
4018 for (memb_types = TYPE_FIELDS (type); memb_types;
4019 memb_types = TREE_CHAIN (memb_types))
4021 tree memb_type = TREE_TYPE (memb_types);
4023 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
4024 TYPE_MAIN_VARIANT (rhstype)))
4027 if (TREE_CODE (memb_type) != POINTER_TYPE)
4030 if (coder == POINTER_TYPE)
4032 register tree ttl = TREE_TYPE (memb_type);
4033 register tree ttr = TREE_TYPE (rhstype);
4035 /* Any non-function converts to a [const][volatile] void *
4036 and vice versa; otherwise, targets must be the same.
4037 Meanwhile, the lhs target must have all the qualifiers of
4039 if (TYPE_MAIN_VARIANT (ttl) == void_type_node
4040 || TYPE_MAIN_VARIANT (ttr) == void_type_node
4041 || comp_target_types (memb_type, rhstype))
4043 /* If this type won't generate any warnings, use it. */
4044 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
4045 || ((TREE_CODE (ttr) == FUNCTION_TYPE
4046 && TREE_CODE (ttl) == FUNCTION_TYPE)
4047 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
4048 == TYPE_QUALS (ttr))
4049 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
4050 == TYPE_QUALS (ttl))))
4053 /* Keep looking for a better type, but remember this one. */
4054 if (! marginal_memb_type)
4055 marginal_memb_type = memb_type;
4059 /* Can convert integer zero to any pointer type. */
4060 if (integer_zerop (rhs)
4061 || (TREE_CODE (rhs) == NOP_EXPR
4062 && integer_zerop (TREE_OPERAND (rhs, 0))))
4064 rhs = null_pointer_node;
4069 if (memb_types || marginal_memb_type)
4073 /* We have only a marginally acceptable member type;
4074 it needs a warning. */
4075 register tree ttl = TREE_TYPE (marginal_memb_type);
4076 register tree ttr = TREE_TYPE (rhstype);
4078 /* Const and volatile mean something different for function
4079 types, so the usual warnings are not appropriate. */
4080 if (TREE_CODE (ttr) == FUNCTION_TYPE
4081 && TREE_CODE (ttl) == FUNCTION_TYPE)
4083 /* Because const and volatile on functions are
4084 restrictions that say the function will not do
4085 certain things, it is okay to use a const or volatile
4086 function where an ordinary one is wanted, but not
4088 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4089 warn_for_assignment ("%s makes qualified function pointer from unqualified",
4090 errtype, funname, parmnum);
4092 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4093 warn_for_assignment ("%s discards qualifiers from pointer target type",
4098 if (pedantic && ! DECL_IN_SYSTEM_HEADER (fundecl))
4099 pedwarn ("ANSI C prohibits argument conversion to union type");
4101 return build1 (NOP_EXPR, type, rhs);
4105 /* Conversions among pointers */
4106 else if (codel == POINTER_TYPE && coder == POINTER_TYPE)
4108 register tree ttl = TREE_TYPE (type);
4109 register tree ttr = TREE_TYPE (rhstype);
4111 /* Any non-function converts to a [const][volatile] void *
4112 and vice versa; otherwise, targets must be the same.
4113 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4114 if (TYPE_MAIN_VARIANT (ttl) == void_type_node
4115 || TYPE_MAIN_VARIANT (ttr) == void_type_node
4116 || comp_target_types (type, rhstype)
4117 || (unsigned_type (TYPE_MAIN_VARIANT (ttl))
4118 == unsigned_type (TYPE_MAIN_VARIANT (ttr))))
4121 && ((TYPE_MAIN_VARIANT (ttl) == void_type_node
4122 && TREE_CODE (ttr) == FUNCTION_TYPE)
4124 (TYPE_MAIN_VARIANT (ttr) == void_type_node
4125 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4126 which are not ANSI null ptr constants. */
4127 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
4128 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4129 warn_for_assignment ("ANSI forbids %s between function pointer and `void *'",
4130 errtype, funname, parmnum);
4131 /* Const and volatile mean something different for function types,
4132 so the usual warnings are not appropriate. */
4133 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4134 && TREE_CODE (ttl) != FUNCTION_TYPE)
4136 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4137 warn_for_assignment ("%s discards qualifiers from pointer target type",
4138 errtype, funname, parmnum);
4139 /* If this is not a case of ignoring a mismatch in signedness,
4141 else if (TYPE_MAIN_VARIANT (ttl) == void_type_node
4142 || TYPE_MAIN_VARIANT (ttr) == void_type_node
4143 || comp_target_types (type, rhstype))
4145 /* If there is a mismatch, do warn. */
4147 warn_for_assignment ("pointer targets in %s differ in signedness",
4148 errtype, funname, parmnum);
4150 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4151 && TREE_CODE (ttr) == FUNCTION_TYPE)
4153 /* Because const and volatile on functions are restrictions
4154 that say the function will not do certain things,
4155 it is okay to use a const or volatile function
4156 where an ordinary one is wanted, but not vice-versa. */
4157 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4158 warn_for_assignment ("%s makes qualified function pointer from unqualified",
4159 errtype, funname, parmnum);
4163 warn_for_assignment ("%s from incompatible pointer type",
4164 errtype, funname, parmnum);
4165 return convert (type, rhs);
4167 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4169 /* An explicit constant 0 can convert to a pointer,
4170 or one that results from arithmetic, even including
4171 a cast to integer type. */
4172 if (! (TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
4174 ! (TREE_CODE (rhs) == NOP_EXPR
4175 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
4176 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
4177 && integer_zerop (TREE_OPERAND (rhs, 0))))
4179 warn_for_assignment ("%s makes pointer from integer without a cast",
4180 errtype, funname, parmnum);
4181 return convert (type, rhs);
4183 return null_pointer_node;
4185 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4187 warn_for_assignment ("%s makes integer from pointer without a cast",
4188 errtype, funname, parmnum);
4189 return convert (type, rhs);
4196 tree selector = maybe_building_objc_message_expr ();
4198 if (selector && parmnum > 2)
4199 error ("incompatible type for argument %d of `%s'",
4200 parmnum - 2, IDENTIFIER_POINTER (selector));
4202 error ("incompatible type for argument %d of `%s'",
4203 parmnum, IDENTIFIER_POINTER (funname));
4206 error ("incompatible type for argument %d of indirect function call",
4210 error ("incompatible types in %s", errtype);
4212 return error_mark_node;
4215 /* Print a warning using MSGID.
4216 It gets OPNAME as its one parameter.
4217 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4218 FUNCTION and ARGNUM are handled specially if we are building an
4219 Objective-C selector. */
4222 warn_for_assignment (msgid, opname, function, argnum)
4230 tree selector = maybe_building_objc_message_expr ();
4233 if (selector && argnum > 2)
4235 function = selector;
4240 /* Function name is known; supply it. */
4241 const char *argstring = _("passing arg %d of `%s'");
4242 new_opname = (char *) alloca (IDENTIFIER_LENGTH (function)
4243 + strlen (argstring) + 1 + 25
4245 sprintf (new_opname, argstring, argnum,
4246 IDENTIFIER_POINTER (function));
4250 /* Function name unknown (call through ptr); just give arg number.*/
4251 const char *argnofun = _("passing arg %d of pointer to function");
4252 new_opname = (char *) alloca (strlen (argnofun) + 1 + 25 /*%d*/ + 1);
4253 sprintf (new_opname, argnofun, argnum);
4255 opname = new_opname;
4257 pedwarn (msgid, opname);
4260 /* If VALUE is a compound expr all of whose expressions are constant, then
4261 return its value. Otherwise, return error_mark_node.
4263 This is for handling COMPOUND_EXPRs as initializer elements
4264 which is allowed with a warning when -pedantic is specified. */
4267 valid_compound_expr_initializer (value, endtype)
4271 if (TREE_CODE (value) == COMPOUND_EXPR)
4273 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4275 return error_mark_node;
4276 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4279 else if (! TREE_CONSTANT (value)
4280 && ! initializer_constant_valid_p (value, endtype))
4281 return error_mark_node;
4286 /* Perform appropriate conversions on the initial value of a variable,
4287 store it in the declaration DECL,
4288 and print any error messages that are appropriate.
4289 If the init is invalid, store an ERROR_MARK. */
4292 store_init_value (decl, init)
4295 register tree value, type;
4297 /* If variable's type was invalidly declared, just ignore it. */
4299 type = TREE_TYPE (decl);
4300 if (TREE_CODE (type) == ERROR_MARK)
4303 /* Digest the specified initializer into an expression. */
4305 value = digest_init (type, init, TREE_STATIC (decl),
4306 TREE_STATIC (decl) || pedantic);
4308 /* Store the expression if valid; else report error. */
4311 /* Note that this is the only place we can detect the error
4312 in a case such as struct foo bar = (struct foo) { x, y };
4313 where there is one initial value which is a constructor expression. */
4314 if (value == error_mark_node)
4316 else if (TREE_STATIC (decl) && ! TREE_CONSTANT (value))
4318 error ("initializer for static variable is not constant");
4319 value = error_mark_node;
4321 else if (TREE_STATIC (decl)
4322 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
4324 error ("initializer for static variable uses complicated arithmetic");
4325 value = error_mark_node;
4329 if (pedantic && TREE_CODE (value) == CONSTRUCTOR)
4331 if (! TREE_CONSTANT (value))
4332 pedwarn ("aggregate initializer is not constant");
4333 else if (! TREE_STATIC (value))
4334 pedwarn ("aggregate initializer uses complicated arithmetic");
4339 DECL_INITIAL (decl) = value;
4341 /* ANSI wants warnings about out-of-range constant initializers. */
4342 STRIP_TYPE_NOPS (value);
4343 constant_expression_warning (value);
4346 /* Methods for storing and printing names for error messages. */
4348 /* Implement a spelling stack that allows components of a name to be pushed
4349 and popped. Each element on the stack is this structure. */
4361 #define SPELLING_STRING 1
4362 #define SPELLING_MEMBER 2
4363 #define SPELLING_BOUNDS 3
4365 static struct spelling *spelling; /* Next stack element (unused). */
4366 static struct spelling *spelling_base; /* Spelling stack base. */
4367 static int spelling_size; /* Size of the spelling stack. */
4369 /* Macros to save and restore the spelling stack around push_... functions.
4370 Alternative to SAVE_SPELLING_STACK. */
4372 #define SPELLING_DEPTH() (spelling - spelling_base)
4373 #define RESTORE_SPELLING_DEPTH(depth) (spelling = spelling_base + depth)
4375 /* Save and restore the spelling stack around arbitrary C code. */
4377 #define SAVE_SPELLING_DEPTH(code) \
4379 int __depth = SPELLING_DEPTH (); \
4381 RESTORE_SPELLING_DEPTH (__depth); \
4384 /* Push an element on the spelling stack with type KIND and assign VALUE
4387 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4389 int depth = SPELLING_DEPTH (); \
4391 if (depth >= spelling_size) \
4393 spelling_size += 10; \
4394 if (spelling_base == 0) \
4396 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4399 = (struct spelling *) xrealloc (spelling_base, \
4400 spelling_size * sizeof (struct spelling)); \
4401 RESTORE_SPELLING_DEPTH (depth); \
4404 spelling->kind = (KIND); \
4405 spelling->MEMBER = (VALUE); \
4409 /* Push STRING on the stack. Printed literally. */
4412 push_string (string)
4415 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4418 /* Push a member name on the stack. Printed as '.' STRING. */
4421 push_member_name (decl)
4426 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4427 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4430 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4433 push_array_bounds (bounds)
4436 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4439 /* Compute the maximum size in bytes of the printed spelling. */
4444 register int size = 0;
4445 register struct spelling *p;
4447 for (p = spelling_base; p < spelling; p++)
4449 if (p->kind == SPELLING_BOUNDS)
4452 size += strlen (p->u.s) + 1;
4458 /* Print the spelling to BUFFER and return it. */
4461 print_spelling (buffer)
4462 register char *buffer;
4464 register char *d = buffer;
4465 register struct spelling *p;
4467 for (p = spelling_base; p < spelling; p++)
4468 if (p->kind == SPELLING_BOUNDS)
4470 sprintf (d, "[%d]", p->u.i);
4475 register const char *s;
4476 if (p->kind == SPELLING_MEMBER)
4478 for (s = p->u.s; (*d = *s++); d++)
4485 /* Issue an error message for a bad initializer component.
4486 MSGID identifies the message.
4487 The component name is taken from the spelling stack. */
4495 error ("%s", msgid);
4496 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4498 error ("(near initialization for `%s')", ofwhat);
4501 /* Issue a pedantic warning for a bad initializer component.
4502 MSGID identifies the message.
4503 The component name is taken from the spelling stack. */
4506 pedwarn_init (msgid)
4511 pedwarn ("%s", msgid);
4512 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4514 pedwarn ("(near initialization for `%s')", ofwhat);
4517 /* Issue a warning for a bad initializer component.
4518 MSGID identifies the message.
4519 The component name is taken from the spelling stack. */
4522 warning_init (msgid)
4527 warning ("%s", msgid);
4528 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4530 warning ("(near initialization for `%s')", ofwhat);
4533 /* Digest the parser output INIT as an initializer for type TYPE.
4534 Return a C expression of type TYPE to represent the initial value.
4536 The arguments REQUIRE_CONSTANT and CONSTRUCTOR_CONSTANT request errors
4537 if non-constant initializers or elements are seen. CONSTRUCTOR_CONSTANT
4538 applies only to elements of constructors. */
4541 digest_init (type, init, require_constant, constructor_constant)
4543 int require_constant, constructor_constant;
4545 enum tree_code code = TREE_CODE (type);
4546 tree inside_init = init;
4548 if (type == error_mark_node || init == error_mark_node)
4549 return error_mark_node;
4551 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4552 /* Do not use STRIP_NOPS here. We do not want an enumerator
4553 whose value is 0 to count as a null pointer constant. */
4554 if (TREE_CODE (init) == NON_LVALUE_EXPR)
4555 inside_init = TREE_OPERAND (init, 0);
4557 /* Initialization of an array of chars from a string constant
4558 optionally enclosed in braces. */
4560 if (code == ARRAY_TYPE)
4562 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4563 if ((typ1 == char_type_node
4564 || typ1 == signed_char_type_node
4565 || typ1 == unsigned_char_type_node
4566 || typ1 == unsigned_wchar_type_node
4567 || typ1 == signed_wchar_type_node)
4568 && ((inside_init && TREE_CODE (inside_init) == STRING_CST)))
4570 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4571 TYPE_MAIN_VARIANT (type)))
4574 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4576 && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node))
4578 error_init ("char-array initialized from wide string");
4579 return error_mark_node;
4581 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4583 && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node))
4585 error_init ("int-array initialized from non-wide string");
4586 return error_mark_node;
4589 TREE_TYPE (inside_init) = type;
4590 if (TYPE_DOMAIN (type) != 0
4591 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
4593 register int size = TREE_INT_CST_LOW (TYPE_SIZE (type));
4594 size = (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
4595 /* Subtract 1 (or sizeof (wchar_t))
4596 because it's ok to ignore the terminating null char
4597 that is counted in the length of the constant. */
4598 if (size < TREE_STRING_LENGTH (inside_init)
4599 - (TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node)
4600 ? TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT
4602 pedwarn_init ("initializer-string for array of chars is too long");
4608 /* Any type can be initialized
4609 from an expression of the same type, optionally with braces. */
4611 if (inside_init && TREE_TYPE (inside_init) != 0
4612 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4613 TYPE_MAIN_VARIANT (type))
4614 || (code == ARRAY_TYPE
4615 && comptypes (TREE_TYPE (inside_init), type))
4616 || (code == POINTER_TYPE
4617 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4618 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE)
4619 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4620 TREE_TYPE (type)))))
4622 if (code == POINTER_TYPE
4623 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4624 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE))
4625 inside_init = default_conversion (inside_init);
4626 else if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4627 && TREE_CODE (inside_init) != CONSTRUCTOR)
4629 error_init ("array initialized from non-constant array expression");
4630 return error_mark_node;
4633 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4634 inside_init = decl_constant_value (inside_init);
4636 /* Compound expressions can only occur here if -pedantic or
4637 -pedantic-errors is specified. In the later case, we always want
4638 an error. In the former case, we simply want a warning. */
4639 if (require_constant && pedantic
4640 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4643 = valid_compound_expr_initializer (inside_init,
4644 TREE_TYPE (inside_init));
4645 if (inside_init == error_mark_node)
4646 error_init ("initializer element is not constant");
4648 pedwarn_init ("initializer element is not constant");
4649 if (flag_pedantic_errors)
4650 inside_init = error_mark_node;
4652 else if (require_constant && ! TREE_CONSTANT (inside_init))
4654 error_init ("initializer element is not constant");
4655 inside_init = error_mark_node;
4657 else if (require_constant
4658 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4660 error_init ("initializer element is not computable at load time");
4661 inside_init = error_mark_node;
4667 /* Handle scalar types, including conversions. */
4669 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4670 || code == ENUMERAL_TYPE || code == COMPLEX_TYPE)
4672 /* Note that convert_for_assignment calls default_conversion
4673 for arrays and functions. We must not call it in the
4674 case where inside_init is a null pointer constant. */
4676 = convert_for_assignment (type, init, _("initialization"),
4677 NULL_TREE, NULL_TREE, 0);
4679 if (require_constant && ! TREE_CONSTANT (inside_init))
4681 error_init ("initializer element is not constant");
4682 inside_init = error_mark_node;
4684 else if (require_constant
4685 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4687 error_init ("initializer element is not computable at load time");
4688 inside_init = error_mark_node;
4694 /* Come here only for records and arrays. */
4696 if (TYPE_SIZE (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4698 error_init ("variable-sized object may not be initialized");
4699 return error_mark_node;
4702 /* Traditionally, you can write struct foo x = 0;
4703 and it initializes the first element of x to 0. */
4704 if (flag_traditional)
4706 tree top = 0, prev = 0, otype = type;
4707 while (TREE_CODE (type) == RECORD_TYPE
4708 || TREE_CODE (type) == ARRAY_TYPE
4709 || TREE_CODE (type) == QUAL_UNION_TYPE
4710 || TREE_CODE (type) == UNION_TYPE)
4712 tree temp = build (CONSTRUCTOR, type, NULL_TREE, NULL_TREE);
4716 TREE_OPERAND (prev, 1) = build_tree_list (NULL_TREE, temp);
4718 if (TREE_CODE (type) == ARRAY_TYPE)
4719 type = TREE_TYPE (type);
4720 else if (TYPE_FIELDS (type))
4721 type = TREE_TYPE (TYPE_FIELDS (type));
4724 error_init ("invalid initializer");
4725 return error_mark_node;
4731 TREE_OPERAND (prev, 1)
4732 = build_tree_list (NULL_TREE,
4733 digest_init (type, init, require_constant,
4734 constructor_constant));
4738 return error_mark_node;
4740 error_init ("invalid initializer");
4741 return error_mark_node;
4744 /* Handle initializers that use braces. */
4746 /* Type of object we are accumulating a constructor for.
4747 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4748 static tree constructor_type;
4750 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4752 static tree constructor_fields;
4754 /* For an ARRAY_TYPE, this is the specified index
4755 at which to store the next element we get.
4756 This is a special INTEGER_CST node that we modify in place. */
4757 static tree constructor_index;
4759 /* For an ARRAY_TYPE, this is the end index of the range
4760 to initialize with the next element, or NULL in the ordinary case
4761 where the element is used just once. */
4762 static tree constructor_range_end;
4764 /* For an ARRAY_TYPE, this is the maximum index. */
4765 static tree constructor_max_index;
4767 /* For a RECORD_TYPE, this is the first field not yet written out. */
4768 static tree constructor_unfilled_fields;
4770 /* For an ARRAY_TYPE, this is the index of the first element
4771 not yet written out.
4772 This is a special INTEGER_CST node that we modify in place. */
4773 static tree constructor_unfilled_index;
4775 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4776 This is so we can generate gaps between fields, when appropriate.
4777 This is a special INTEGER_CST node that we modify in place. */
4778 static tree constructor_bit_index;
4780 /* If we are saving up the elements rather than allocating them,
4781 this is the list of elements so far (in reverse order,
4782 most recent first). */
4783 static tree constructor_elements;
4785 /* 1 if so far this constructor's elements are all compile-time constants. */
4786 static int constructor_constant;
4788 /* 1 if so far this constructor's elements are all valid address constants. */
4789 static int constructor_simple;
4791 /* 1 if this constructor is erroneous so far. */
4792 static int constructor_erroneous;
4794 /* 1 if have called defer_addressed_constants. */
4795 static int constructor_subconstants_deferred;
4797 /* Structure for managing pending initializer elements, organized as an
4802 struct init_node *left, *right;
4803 struct init_node *parent;
4809 /* Tree of pending elements at this constructor level.
4810 These are elements encountered out of order
4811 which belong at places we haven't reached yet in actually
4812 writing the output. */
4813 static struct init_node *constructor_pending_elts;
4815 /* The SPELLING_DEPTH of this constructor. */
4816 static int constructor_depth;
4818 /* 0 if implicitly pushing constructor levels is allowed. */
4819 int constructor_no_implicit = 0; /* 0 for C; 1 for some other languages. */
4821 static int require_constant_value;
4822 static int require_constant_elements;
4824 /* 1 if it is ok to output this constructor as we read it.
4825 0 means must accumulate a CONSTRUCTOR expression. */
4826 static int constructor_incremental;
4828 /* DECL node for which an initializer is being read.
4829 0 means we are reading a constructor expression
4830 such as (struct foo) {...}. */
4831 static tree constructor_decl;
4833 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4834 static char *constructor_asmspec;
4836 /* Nonzero if this is an initializer for a top-level decl. */
4837 static int constructor_top_level;
4840 /* This stack has a level for each implicit or explicit level of
4841 structuring in the initializer, including the outermost one. It
4842 saves the values of most of the variables above. */
4844 struct constructor_stack
4846 struct constructor_stack *next;
4852 tree unfilled_index;
4853 tree unfilled_fields;
4857 struct init_node *pending_elts;
4859 /* If nonzero, this value should replace the entire
4860 constructor at this level. */
4861 tree replacement_value;
4870 struct constructor_stack *constructor_stack;
4872 /* This stack records separate initializers that are nested.
4873 Nested initializers can't happen in ANSI C, but GNU C allows them
4874 in cases like { ... (struct foo) { ... } ... }. */
4876 struct initializer_stack
4878 struct initializer_stack *next;
4881 struct constructor_stack *constructor_stack;
4883 struct spelling *spelling;
4884 struct spelling *spelling_base;
4888 char require_constant_value;
4889 char require_constant_elements;
4893 struct initializer_stack *initializer_stack;
4895 /* Prepare to parse and output the initializer for variable DECL. */
4898 start_init (decl, asmspec_tree, top_level)
4904 struct initializer_stack *p
4905 = (struct initializer_stack *) xmalloc (sizeof (struct initializer_stack));
4909 asmspec = TREE_STRING_POINTER (asmspec_tree);
4911 p->decl = constructor_decl;
4912 p->asmspec = constructor_asmspec;
4913 p->incremental = constructor_incremental;
4914 p->require_constant_value = require_constant_value;
4915 p->require_constant_elements = require_constant_elements;
4916 p->constructor_stack = constructor_stack;
4917 p->elements = constructor_elements;
4918 p->spelling = spelling;
4919 p->spelling_base = spelling_base;
4920 p->spelling_size = spelling_size;
4921 p->deferred = constructor_subconstants_deferred;
4922 p->top_level = constructor_top_level;
4923 p->next = initializer_stack;
4924 initializer_stack = p;
4926 constructor_decl = decl;
4927 constructor_incremental = top_level;
4928 constructor_asmspec = asmspec;
4929 constructor_subconstants_deferred = 0;
4930 constructor_top_level = top_level;
4934 require_constant_value = TREE_STATIC (decl);
4935 require_constant_elements
4936 = ((TREE_STATIC (decl) || pedantic)
4937 /* For a scalar, you can always use any value to initialize,
4938 even within braces. */
4939 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4940 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4941 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4942 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4943 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4944 constructor_incremental |= TREE_STATIC (decl);
4948 require_constant_value = 0;
4949 require_constant_elements = 0;
4950 locus = "(anonymous)";
4953 constructor_stack = 0;
4955 missing_braces_mentioned = 0;
4959 RESTORE_SPELLING_DEPTH (0);
4962 push_string (locus);
4968 struct initializer_stack *p = initializer_stack;
4970 /* Output subconstants (string constants, usually)
4971 that were referenced within this initializer and saved up.
4972 Must do this if and only if we called defer_addressed_constants. */
4973 if (constructor_subconstants_deferred)
4974 output_deferred_addressed_constants ();
4976 /* Free the whole constructor stack of this initializer. */
4977 while (constructor_stack)
4979 struct constructor_stack *q = constructor_stack;
4980 constructor_stack = q->next;
4984 /* Pop back to the data of the outer initializer (if any). */
4985 constructor_decl = p->decl;
4986 constructor_asmspec = p->asmspec;
4987 constructor_incremental = p->incremental;
4988 require_constant_value = p->require_constant_value;
4989 require_constant_elements = p->require_constant_elements;
4990 constructor_stack = p->constructor_stack;
4991 constructor_elements = p->elements;
4992 spelling = p->spelling;
4993 spelling_base = p->spelling_base;
4994 spelling_size = p->spelling_size;
4995 constructor_subconstants_deferred = p->deferred;
4996 constructor_top_level = p->top_level;
4997 initializer_stack = p->next;
5001 /* Call here when we see the initializer is surrounded by braces.
5002 This is instead of a call to push_init_level;
5003 it is matched by a call to pop_init_level.
5005 TYPE is the type to initialize, for a constructor expression.
5006 For an initializer for a decl, TYPE is zero. */
5009 really_start_incremental_init (type)
5012 struct constructor_stack *p
5013 = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5016 type = TREE_TYPE (constructor_decl);
5018 /* Turn off constructor_incremental if type is a struct with bitfields.
5019 Do this before the first push, so that the corrected value
5020 is available in finish_init. */
5021 check_init_type_bitfields (type);
5023 p->type = constructor_type;
5024 p->fields = constructor_fields;
5025 p->index = constructor_index;
5026 p->range_end = constructor_range_end;
5027 p->max_index = constructor_max_index;
5028 p->unfilled_index = constructor_unfilled_index;
5029 p->unfilled_fields = constructor_unfilled_fields;
5030 p->bit_index = constructor_bit_index;
5031 p->elements = constructor_elements;
5032 p->constant = constructor_constant;
5033 p->simple = constructor_simple;
5034 p->erroneous = constructor_erroneous;
5035 p->pending_elts = constructor_pending_elts;
5036 p->depth = constructor_depth;
5037 p->replacement_value = 0;
5039 p->incremental = constructor_incremental;
5042 constructor_stack = p;
5044 constructor_constant = 1;
5045 constructor_simple = 1;
5046 constructor_depth = SPELLING_DEPTH ();
5047 constructor_elements = 0;
5048 constructor_pending_elts = 0;
5049 constructor_type = type;
5051 if (TREE_CODE (constructor_type) == RECORD_TYPE
5052 || TREE_CODE (constructor_type) == UNION_TYPE)
5054 constructor_fields = TYPE_FIELDS (constructor_type);
5055 /* Skip any nameless bit fields at the beginning. */
5056 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5057 && DECL_NAME (constructor_fields) == 0)
5058 constructor_fields = TREE_CHAIN (constructor_fields);
5059 constructor_unfilled_fields = constructor_fields;
5060 constructor_bit_index = copy_node (integer_zero_node);
5061 TREE_TYPE (constructor_bit_index) = sbitsizetype;
5063 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5065 constructor_range_end = 0;
5066 if (TYPE_DOMAIN (constructor_type))
5068 constructor_max_index
5069 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5071 = copy_node (TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5074 constructor_index = copy_node (integer_zero_node);
5075 constructor_unfilled_index = copy_node (constructor_index);
5079 /* Handle the case of int x = {5}; */
5080 constructor_fields = constructor_type;
5081 constructor_unfilled_fields = constructor_type;
5084 if (constructor_incremental)
5086 int momentary = suspend_momentary ();
5087 push_obstacks_nochange ();
5088 if (TREE_PERMANENT (constructor_decl))
5089 end_temporary_allocation ();
5090 make_decl_rtl (constructor_decl, constructor_asmspec,
5091 constructor_top_level);
5092 assemble_variable (constructor_decl, constructor_top_level, 0, 1);
5094 resume_momentary (momentary);
5097 if (constructor_incremental)
5099 defer_addressed_constants ();
5100 constructor_subconstants_deferred = 1;
5104 /* Push down into a subobject, for initialization.
5105 If this is for an explicit set of braces, IMPLICIT is 0.
5106 If it is because the next element belongs at a lower level,
5110 push_init_level (implicit)
5113 struct constructor_stack *p;
5115 /* If we've exhausted any levels that didn't have braces,
5117 while (constructor_stack->implicit)
5119 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5120 || TREE_CODE (constructor_type) == UNION_TYPE)
5121 && constructor_fields == 0)
5122 process_init_element (pop_init_level (1));
5123 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5124 && tree_int_cst_lt (constructor_max_index, constructor_index))
5125 process_init_element (pop_init_level (1));
5130 /* Structure elements may require alignment. Do this now if necessary
5131 for the subaggregate, and if it comes next in sequence. Don't do
5132 this for subaggregates that will go on the pending list. */
5133 if (constructor_incremental && constructor_type != 0
5134 && TREE_CODE (constructor_type) == RECORD_TYPE && constructor_fields
5135 && constructor_fields == constructor_unfilled_fields)
5137 /* Advance to offset of this element. */
5138 if (! tree_int_cst_equal (constructor_bit_index,
5139 DECL_FIELD_BITPOS (constructor_fields)))
5141 /* By using unsigned arithmetic, the result will be correct even
5142 in case of overflows, if BITS_PER_UNIT is a power of two. */
5143 unsigned next = (TREE_INT_CST_LOW
5144 (DECL_FIELD_BITPOS (constructor_fields))
5145 / (unsigned)BITS_PER_UNIT);
5146 unsigned here = (TREE_INT_CST_LOW (constructor_bit_index)
5147 / (unsigned)BITS_PER_UNIT);
5149 assemble_zeros ((next - here)
5150 * (unsigned)BITS_PER_UNIT
5151 / (unsigned)BITS_PER_UNIT);
5153 /* Indicate that we have now filled the structure up to the current
5155 constructor_unfilled_fields = constructor_fields;
5158 p = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5159 p->type = constructor_type;
5160 p->fields = constructor_fields;
5161 p->index = constructor_index;
5162 p->range_end = constructor_range_end;
5163 p->max_index = constructor_max_index;
5164 p->unfilled_index = constructor_unfilled_index;
5165 p->unfilled_fields = constructor_unfilled_fields;
5166 p->bit_index = constructor_bit_index;
5167 p->elements = constructor_elements;
5168 p->constant = constructor_constant;
5169 p->simple = constructor_simple;
5170 p->erroneous = constructor_erroneous;
5171 p->pending_elts = constructor_pending_elts;
5172 p->depth = constructor_depth;
5173 p->replacement_value = 0;
5174 p->implicit = implicit;
5175 p->incremental = constructor_incremental;
5177 p->next = constructor_stack;
5178 constructor_stack = p;
5180 constructor_constant = 1;
5181 constructor_simple = 1;
5182 constructor_depth = SPELLING_DEPTH ();
5183 constructor_elements = 0;
5184 constructor_pending_elts = 0;
5186 /* Don't die if an entire brace-pair level is superfluous
5187 in the containing level. */
5188 if (constructor_type == 0)
5190 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5191 || TREE_CODE (constructor_type) == UNION_TYPE)
5193 /* Don't die if there are extra init elts at the end. */
5194 if (constructor_fields == 0)
5195 constructor_type = 0;
5198 constructor_type = TREE_TYPE (constructor_fields);
5199 push_member_name (constructor_fields);
5200 constructor_depth++;
5201 if (constructor_fields != constructor_unfilled_fields)
5202 constructor_incremental = 0;
5205 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5207 constructor_type = TREE_TYPE (constructor_type);
5208 push_array_bounds (TREE_INT_CST_LOW (constructor_index));
5209 constructor_depth++;
5210 if (! tree_int_cst_equal (constructor_index, constructor_unfilled_index)
5211 || constructor_range_end != 0)
5212 constructor_incremental = 0;
5215 if (constructor_type == 0)
5217 error_init ("extra brace group at end of initializer");
5218 constructor_fields = 0;
5219 constructor_unfilled_fields = 0;
5223 /* Turn off constructor_incremental if type is a struct with bitfields. */
5224 check_init_type_bitfields (constructor_type);
5226 if (implicit && warn_missing_braces && !missing_braces_mentioned)
5228 missing_braces_mentioned = 1;
5229 warning_init ("missing braces around initializer");
5232 if (TREE_CODE (constructor_type) == RECORD_TYPE
5233 || TREE_CODE (constructor_type) == UNION_TYPE)
5235 constructor_fields = TYPE_FIELDS (constructor_type);
5236 /* Skip any nameless bit fields at the beginning. */
5237 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5238 && DECL_NAME (constructor_fields) == 0)
5239 constructor_fields = TREE_CHAIN (constructor_fields);
5240 constructor_unfilled_fields = constructor_fields;
5241 constructor_bit_index = copy_node (integer_zero_node);
5242 TREE_TYPE (constructor_bit_index) = sbitsizetype;
5244 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5246 constructor_range_end = 0;
5247 if (TYPE_DOMAIN (constructor_type))
5249 constructor_max_index
5250 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5252 = copy_node (TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5255 constructor_index = copy_node (integer_zero_node);
5256 constructor_unfilled_index = copy_node (constructor_index);
5260 warning_init ("braces around scalar initializer");
5261 constructor_fields = constructor_type;
5262 constructor_unfilled_fields = constructor_type;
5266 /* Don't read a struct incrementally if it has any bitfields,
5267 because the incremental reading code doesn't know how to
5268 handle bitfields yet. */
5271 check_init_type_bitfields (type)
5274 if (TREE_CODE (type) == RECORD_TYPE)
5277 for (tail = TYPE_FIELDS (type); tail;
5278 tail = TREE_CHAIN (tail))
5280 if (DECL_C_BIT_FIELD (tail))
5282 constructor_incremental = 0;
5286 check_init_type_bitfields (TREE_TYPE (tail));
5290 else if (TREE_CODE (type) == UNION_TYPE)
5292 tree tail = TYPE_FIELDS (type);
5293 if (tail && DECL_C_BIT_FIELD (tail))
5294 /* We also use the nonincremental algorithm for initiliazation
5295 of unions whose first member is a bitfield, becuase the
5296 incremental algorithm has no code for dealing with
5298 constructor_incremental = 0;
5301 else if (TREE_CODE (type) == ARRAY_TYPE)
5302 check_init_type_bitfields (TREE_TYPE (type));
5305 /* At the end of an implicit or explicit brace level,
5306 finish up that level of constructor.
5307 If we were outputting the elements as they are read, return 0
5308 from inner levels (process_init_element ignores that),
5309 but return error_mark_node from the outermost level
5310 (that's what we want to put in DECL_INITIAL).
5311 Otherwise, return a CONSTRUCTOR expression. */
5314 pop_init_level (implicit)
5317 struct constructor_stack *p;
5319 tree constructor = 0;
5323 /* When we come to an explicit close brace,
5324 pop any inner levels that didn't have explicit braces. */
5325 while (constructor_stack->implicit)
5326 process_init_element (pop_init_level (1));
5329 p = constructor_stack;
5331 if (constructor_type != 0)
5332 size = int_size_in_bytes (constructor_type);
5334 /* Warn when some struct elements are implicitly initialized to zero. */
5337 && TREE_CODE (constructor_type) == RECORD_TYPE
5338 && constructor_unfilled_fields)
5340 push_member_name (constructor_unfilled_fields);
5341 warning_init ("missing initializer");
5342 RESTORE_SPELLING_DEPTH (constructor_depth);
5345 /* Now output all pending elements. */
5346 output_pending_init_elements (1);
5348 #if 0 /* c-parse.in warns about {}. */
5349 /* In ANSI, each brace level must have at least one element. */
5350 if (! implicit && pedantic
5351 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5352 ? integer_zerop (constructor_unfilled_index)
5353 : constructor_unfilled_fields == TYPE_FIELDS (constructor_type)))
5354 pedwarn_init ("empty braces in initializer");
5357 /* Pad out the end of the structure. */
5359 if (p->replacement_value)
5361 /* If this closes a superfluous brace pair,
5362 just pass out the element between them. */
5363 constructor = p->replacement_value;
5364 /* If this is the top level thing within the initializer,
5365 and it's for a variable, then since we already called
5366 assemble_variable, we must output the value now. */
5367 if (p->next == 0 && constructor_decl != 0
5368 && constructor_incremental)
5370 constructor = digest_init (constructor_type, constructor,
5371 require_constant_value,
5372 require_constant_elements);
5374 /* If initializing an array of unknown size,
5375 determine the size now. */
5376 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5377 && TYPE_DOMAIN (constructor_type) == 0)
5382 push_obstacks_nochange ();
5383 if (TREE_PERMANENT (constructor_type))
5384 end_temporary_allocation ();
5386 momentary_p = suspend_momentary ();
5388 /* We shouldn't have an incomplete array type within
5390 if (constructor_stack->next)
5394 = complete_array_type (constructor_type,
5399 size = int_size_in_bytes (constructor_type);
5400 resume_momentary (momentary_p);
5404 output_constant (constructor, size);
5407 else if (constructor_type == 0)
5409 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5410 && TREE_CODE (constructor_type) != UNION_TYPE
5411 && TREE_CODE (constructor_type) != ARRAY_TYPE
5412 && ! constructor_incremental)
5414 /* A nonincremental scalar initializer--just return
5415 the element, after verifying there is just one. */
5416 if (constructor_elements == 0)
5418 error_init ("empty scalar initializer");
5419 constructor = error_mark_node;
5421 else if (TREE_CHAIN (constructor_elements) != 0)
5423 error_init ("extra elements in scalar initializer");
5424 constructor = TREE_VALUE (constructor_elements);
5427 constructor = TREE_VALUE (constructor_elements);
5429 else if (! constructor_incremental)
5431 if (constructor_erroneous)
5432 constructor = error_mark_node;
5435 int momentary = suspend_momentary ();
5437 constructor = build (CONSTRUCTOR, constructor_type, NULL_TREE,
5438 nreverse (constructor_elements));
5439 if (constructor_constant)
5440 TREE_CONSTANT (constructor) = 1;
5441 if (constructor_constant && constructor_simple)
5442 TREE_STATIC (constructor) = 1;
5444 resume_momentary (momentary);
5450 int momentary = suspend_momentary ();
5452 if (TREE_CODE (constructor_type) == RECORD_TYPE
5453 || TREE_CODE (constructor_type) == UNION_TYPE)
5455 /* Find the offset of the end of that field. */
5456 filled = size_binop (CEIL_DIV_EXPR,
5457 constructor_bit_index,
5458 size_int (BITS_PER_UNIT));
5460 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5462 /* If initializing an array of unknown size,
5463 determine the size now. */
5464 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5465 && TYPE_DOMAIN (constructor_type) == 0)
5468 = size_binop (MINUS_EXPR,
5469 constructor_unfilled_index,
5472 push_obstacks_nochange ();
5473 if (TREE_PERMANENT (constructor_type))
5474 end_temporary_allocation ();
5475 maxindex = copy_node (maxindex);
5476 TYPE_DOMAIN (constructor_type) = build_index_type (maxindex);
5477 TREE_TYPE (maxindex) = TYPE_DOMAIN (constructor_type);
5479 /* TYPE_MAX_VALUE is always one less than the number of elements
5480 in the array, because we start counting at zero. Therefore,
5481 warn only if the value is less than zero. */
5483 && (tree_int_cst_sgn (TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5485 error_with_decl (constructor_decl,
5486 "zero or negative array size `%s'");
5487 layout_type (constructor_type);
5488 size = int_size_in_bytes (constructor_type);
5492 filled = size_binop (MULT_EXPR, constructor_unfilled_index,
5493 size_in_bytes (TREE_TYPE (constructor_type)));
5499 assemble_zeros (size - TREE_INT_CST_LOW (filled));
5501 resume_momentary (momentary);
5505 constructor_type = p->type;
5506 constructor_fields = p->fields;
5507 constructor_index = p->index;
5508 constructor_range_end = p->range_end;
5509 constructor_max_index = p->max_index;
5510 constructor_unfilled_index = p->unfilled_index;
5511 constructor_unfilled_fields = p->unfilled_fields;
5512 constructor_bit_index = p->bit_index;
5513 constructor_elements = p->elements;
5514 constructor_constant = p->constant;
5515 constructor_simple = p->simple;
5516 constructor_erroneous = p->erroneous;
5517 constructor_pending_elts = p->pending_elts;
5518 constructor_depth = p->depth;
5519 constructor_incremental = p->incremental;
5520 RESTORE_SPELLING_DEPTH (constructor_depth);
5522 constructor_stack = p->next;
5525 if (constructor == 0)
5527 if (constructor_stack == 0)
5528 return error_mark_node;
5534 /* Within an array initializer, specify the next index to be initialized.
5535 FIRST is that index. If LAST is nonzero, then initialize a range
5536 of indices, running from FIRST through LAST. */
5539 set_init_index (first, last)
5542 while ((TREE_CODE (first) == NOP_EXPR
5543 || TREE_CODE (first) == CONVERT_EXPR
5544 || TREE_CODE (first) == NON_LVALUE_EXPR)
5545 && (TYPE_MODE (TREE_TYPE (first))
5546 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0)))))
5547 (first) = TREE_OPERAND (first, 0);
5549 while ((TREE_CODE (last) == NOP_EXPR
5550 || TREE_CODE (last) == CONVERT_EXPR
5551 || TREE_CODE (last) == NON_LVALUE_EXPR)
5552 && (TYPE_MODE (TREE_TYPE (last))
5553 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0)))))
5554 (last) = TREE_OPERAND (last, 0);
5556 if (TREE_CODE (first) != INTEGER_CST)
5557 error_init ("nonconstant array index in initializer");
5558 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5559 error_init ("nonconstant array index in initializer");
5560 else if (! constructor_unfilled_index)
5561 error_init ("array index in non-array initializer");
5562 else if (tree_int_cst_lt (first, constructor_unfilled_index))
5563 error_init ("duplicate array index in initializer");
5566 TREE_INT_CST_LOW (constructor_index) = TREE_INT_CST_LOW (first);
5567 TREE_INT_CST_HIGH (constructor_index) = TREE_INT_CST_HIGH (first);
5569 if (last != 0 && tree_int_cst_lt (last, first))
5570 error_init ("empty index range in initializer");
5574 pedwarn ("ANSI C forbids specifying element to initialize");
5575 constructor_range_end = last;
5580 /* Within a struct initializer, specify the next field to be initialized. */
5583 set_init_label (fieldname)
5589 /* Don't die if an entire brace-pair level is superfluous
5590 in the containing level. */
5591 if (constructor_type == 0)
5594 for (tail = TYPE_FIELDS (constructor_type); tail;
5595 tail = TREE_CHAIN (tail))
5597 if (tail == constructor_unfilled_fields)
5599 if (DECL_NAME (tail) == fieldname)
5604 error ("unknown field `%s' specified in initializer",
5605 IDENTIFIER_POINTER (fieldname));
5607 error ("field `%s' already initialized",
5608 IDENTIFIER_POINTER (fieldname));
5611 constructor_fields = tail;
5613 pedwarn ("ANSI C forbids specifying structure member to initialize");
5617 /* Add a new initializer to the tree of pending initializers. PURPOSE
5618 indentifies the initializer, either array index or field in a structure.
5619 VALUE is the value of that index or field. */
5622 add_pending_init (purpose, value)
5623 tree purpose, value;
5625 struct init_node *p, **q, *r;
5627 q = &constructor_pending_elts;
5630 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5635 if (tree_int_cst_lt (purpose, p->purpose))
5637 else if (tree_int_cst_lt (p->purpose, purpose))
5648 if (tree_int_cst_lt (DECL_FIELD_BITPOS (purpose),
5649 DECL_FIELD_BITPOS (p->purpose)))
5651 else if (tree_int_cst_lt (DECL_FIELD_BITPOS (p->purpose),
5652 DECL_FIELD_BITPOS (purpose)))
5659 r = (struct init_node *) oballoc (sizeof (struct init_node));
5660 r->purpose = purpose;
5671 struct init_node *s;
5675 if (p->balance == 0)
5677 else if (p->balance < 0)
5684 p->left->parent = p;
5701 constructor_pending_elts = r;
5706 struct init_node *t = r->right;
5710 r->right->parent = r;
5715 p->left->parent = p;
5718 p->balance = t->balance < 0;
5719 r->balance = -(t->balance > 0);
5734 constructor_pending_elts = t;
5740 /* p->balance == +1; growth of left side balances the node. */
5745 else /* r == p->right */
5747 if (p->balance == 0)
5748 /* Growth propagation from right side. */
5750 else if (p->balance > 0)
5757 p->right->parent = p;
5774 constructor_pending_elts = r;
5776 else /* r->balance == -1 */
5779 struct init_node *t = r->left;
5783 r->left->parent = r;
5788 p->right->parent = p;
5791 r->balance = (t->balance < 0);
5792 p->balance = -(t->balance > 0);
5807 constructor_pending_elts = t;
5813 /* p->balance == -1; growth of right side balances the node. */
5824 /* Return nonzero if FIELD is equal to the index of a pending initializer. */
5827 pending_init_member (field)
5830 struct init_node *p;
5832 p = constructor_pending_elts;
5833 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5837 if (tree_int_cst_equal (field, p->purpose))
5839 else if (tree_int_cst_lt (field, p->purpose))
5849 if (field == p->purpose)
5851 else if (tree_int_cst_lt (DECL_FIELD_BITPOS (field),
5852 DECL_FIELD_BITPOS (p->purpose)))
5862 /* "Output" the next constructor element.
5863 At top level, really output it to assembler code now.
5864 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5865 TYPE is the data type that the containing data type wants here.
5866 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5868 PENDING if non-nil means output pending elements that belong
5869 right after this element. (PENDING is normally 1;
5870 it is 0 while outputting pending elements, to avoid recursion.) */
5873 output_init_element (value, type, field, pending)
5874 tree value, type, field;
5879 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5880 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5881 && !(TREE_CODE (value) == STRING_CST
5882 && TREE_CODE (type) == ARRAY_TYPE
5883 && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE)
5884 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5885 TYPE_MAIN_VARIANT (type))))
5886 value = default_conversion (value);
5888 if (value == error_mark_node)
5889 constructor_erroneous = 1;
5890 else if (!TREE_CONSTANT (value))
5891 constructor_constant = 0;
5892 else if (initializer_constant_valid_p (value, TREE_TYPE (value)) == 0
5893 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5894 || TREE_CODE (constructor_type) == UNION_TYPE)
5895 && DECL_C_BIT_FIELD (field)
5896 && TREE_CODE (value) != INTEGER_CST))
5897 constructor_simple = 0;
5899 if (require_constant_value && ! TREE_CONSTANT (value))
5901 error_init ("initializer element is not constant");
5902 value = error_mark_node;
5904 else if (require_constant_elements
5905 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
5907 error_init ("initializer element is not computable at load time");
5908 value = error_mark_node;
5911 /* If this element duplicates one on constructor_pending_elts,
5912 print a message and ignore it. Don't do this when we're
5913 processing elements taken off constructor_pending_elts,
5914 because we'd always get spurious errors. */
5917 if (TREE_CODE (constructor_type) == RECORD_TYPE
5918 || TREE_CODE (constructor_type) == UNION_TYPE
5919 || TREE_CODE (constructor_type) == ARRAY_TYPE)
5921 if (pending_init_member (field))
5923 error_init ("duplicate initializer");
5929 /* If this element doesn't come next in sequence,
5930 put it on constructor_pending_elts. */
5931 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5932 && !tree_int_cst_equal (field, constructor_unfilled_index))
5935 /* The copy_node is needed in case field is actually
5936 constructor_index, which is modified in place. */
5937 add_pending_init (copy_node (field),
5938 digest_init (type, value, require_constant_value,
5939 require_constant_elements));
5941 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5942 && field != constructor_unfilled_fields)
5944 /* We do this for records but not for unions. In a union,
5945 no matter which field is specified, it can be initialized
5946 right away since it starts at the beginning of the union. */
5948 add_pending_init (field,
5949 digest_init (type, value, require_constant_value,
5950 require_constant_elements));
5954 /* Otherwise, output this element either to
5955 constructor_elements or to the assembler file. */
5959 if (! constructor_incremental)
5961 if (field && TREE_CODE (field) == INTEGER_CST)
5962 field = copy_node (field);
5963 constructor_elements
5964 = tree_cons (field, digest_init (type, value,
5965 require_constant_value,
5966 require_constant_elements),
5967 constructor_elements);
5971 /* Structure elements may require alignment.
5972 Do this, if necessary. */
5973 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5975 /* Advance to offset of this element. */
5976 if (! tree_int_cst_equal (constructor_bit_index,
5977 DECL_FIELD_BITPOS (field)))
5979 /* By using unsigned arithmetic, the result will be
5980 correct even in case of overflows, if BITS_PER_UNIT
5981 is a power of two. */
5982 unsigned next = (TREE_INT_CST_LOW
5983 (DECL_FIELD_BITPOS (field))
5984 / (unsigned)BITS_PER_UNIT);
5985 unsigned here = (TREE_INT_CST_LOW
5986 (constructor_bit_index)
5987 / (unsigned)BITS_PER_UNIT);
5989 assemble_zeros ((next - here)
5990 * (unsigned)BITS_PER_UNIT
5991 / (unsigned)BITS_PER_UNIT);
5994 output_constant (digest_init (type, value,
5995 require_constant_value,
5996 require_constant_elements),
5997 int_size_in_bytes (type));
5999 /* For a record or union,
6000 keep track of end position of last field. */
6001 if (TREE_CODE (constructor_type) == RECORD_TYPE
6002 || TREE_CODE (constructor_type) == UNION_TYPE)
6004 tree temp = size_binop (PLUS_EXPR, DECL_FIELD_BITPOS (field),
6006 TREE_INT_CST_LOW (constructor_bit_index)
6007 = TREE_INT_CST_LOW (temp);
6008 TREE_INT_CST_HIGH (constructor_bit_index)
6009 = TREE_INT_CST_HIGH (temp);
6014 /* Advance the variable that indicates sequential elements output. */
6015 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6017 tree tem = size_binop (PLUS_EXPR, constructor_unfilled_index,
6019 TREE_INT_CST_LOW (constructor_unfilled_index)
6020 = TREE_INT_CST_LOW (tem);
6021 TREE_INT_CST_HIGH (constructor_unfilled_index)
6022 = TREE_INT_CST_HIGH (tem);
6024 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6026 constructor_unfilled_fields =
6027 TREE_CHAIN (constructor_unfilled_fields);
6028 /* Skip any nameless bit fields. */
6029 while (constructor_unfilled_fields != 0
6030 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6031 && DECL_NAME (constructor_unfilled_fields) == 0)
6032 constructor_unfilled_fields =
6033 TREE_CHAIN (constructor_unfilled_fields);
6035 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6036 constructor_unfilled_fields = 0;
6038 /* Now output any pending elements which have become next. */
6040 output_pending_init_elements (0);
6044 /* Output any pending elements which have become next.
6045 As we output elements, constructor_unfilled_{fields,index}
6046 advances, which may cause other elements to become next;
6047 if so, they too are output.
6049 If ALL is 0, we return when there are
6050 no more pending elements to output now.
6052 If ALL is 1, we output space as necessary so that
6053 we can output all the pending elements. */
6056 output_pending_init_elements (all)
6059 struct init_node *elt = constructor_pending_elts;
6064 /* Look thru the whole pending tree.
6065 If we find an element that should be output now,
6066 output it. Otherwise, set NEXT to the element
6067 that comes first among those still pending. */
6072 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6074 if (tree_int_cst_equal (elt->purpose,
6075 constructor_unfilled_index))
6076 output_init_element (elt->value,
6077 TREE_TYPE (constructor_type),
6078 constructor_unfilled_index, 0);
6079 else if (tree_int_cst_lt (constructor_unfilled_index,
6082 /* Advance to the next smaller node. */
6087 /* We have reached the smallest node bigger than the
6088 current unfilled index. Fill the space first. */
6089 next = elt->purpose;
6095 /* Advance to the next bigger node. */
6100 /* We have reached the biggest node in a subtree. Find
6101 the parent of it, which is the next bigger node. */
6102 while (elt->parent && elt->parent->right == elt)
6105 if (elt && tree_int_cst_lt (constructor_unfilled_index,
6108 next = elt->purpose;
6114 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6115 || TREE_CODE (constructor_type) == UNION_TYPE)
6117 /* If the current record is complete we are done. */
6118 if (constructor_unfilled_fields == 0)
6120 if (elt->purpose == constructor_unfilled_fields)
6122 output_init_element (elt->value,
6123 TREE_TYPE (constructor_unfilled_fields),
6124 constructor_unfilled_fields,
6127 else if (tree_int_cst_lt (DECL_FIELD_BITPOS (constructor_unfilled_fields),
6128 DECL_FIELD_BITPOS (elt->purpose)))
6130 /* Advance to the next smaller node. */
6135 /* We have reached the smallest node bigger than the
6136 current unfilled field. Fill the space first. */
6137 next = elt->purpose;
6143 /* Advance to the next bigger node. */
6148 /* We have reached the biggest node in a subtree. Find
6149 the parent of it, which is the next bigger node. */
6150 while (elt->parent && elt->parent->right == elt)
6154 && tree_int_cst_lt (DECL_FIELD_BITPOS (constructor_unfilled_fields),
6155 DECL_FIELD_BITPOS (elt->purpose)))
6157 next = elt->purpose;
6165 /* Ordinarily return, but not if we want to output all
6166 and there are elements left. */
6167 if (! (all && next != 0))
6170 /* Generate space up to the position of NEXT. */
6171 if (constructor_incremental)
6174 tree nextpos_tree = size_int (0);
6176 if (TREE_CODE (constructor_type) == RECORD_TYPE
6177 || TREE_CODE (constructor_type) == UNION_TYPE)
6180 /* Find the last field written out, if any. */
6181 for (tail = TYPE_FIELDS (constructor_type); tail;
6182 tail = TREE_CHAIN (tail))
6183 if (TREE_CHAIN (tail) == constructor_unfilled_fields)
6187 /* Find the offset of the end of that field. */
6188 filled = size_binop (CEIL_DIV_EXPR,
6189 size_binop (PLUS_EXPR,
6190 DECL_FIELD_BITPOS (tail),
6192 size_int (BITS_PER_UNIT));
6194 filled = size_int (0);
6196 nextpos_tree = size_binop (CEIL_DIV_EXPR,
6197 DECL_FIELD_BITPOS (next),
6198 size_int (BITS_PER_UNIT));
6200 TREE_INT_CST_HIGH (constructor_bit_index)
6201 = TREE_INT_CST_HIGH (DECL_FIELD_BITPOS (next));
6202 TREE_INT_CST_LOW (constructor_bit_index)
6203 = TREE_INT_CST_LOW (DECL_FIELD_BITPOS (next));
6204 constructor_unfilled_fields = next;
6206 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6208 filled = size_binop (MULT_EXPR, constructor_unfilled_index,
6209 size_in_bytes (TREE_TYPE (constructor_type)));
6211 = size_binop (MULT_EXPR, next,
6212 size_in_bytes (TREE_TYPE (constructor_type)));
6213 TREE_INT_CST_LOW (constructor_unfilled_index)
6214 = TREE_INT_CST_LOW (next);
6215 TREE_INT_CST_HIGH (constructor_unfilled_index)
6216 = TREE_INT_CST_HIGH (next);
6223 int nextpos = TREE_INT_CST_LOW (nextpos_tree);
6225 assemble_zeros (nextpos - TREE_INT_CST_LOW (filled));
6230 /* If it's not incremental, just skip over the gap,
6231 so that after jumping to retry we will output the next
6232 successive element. */
6233 if (TREE_CODE (constructor_type) == RECORD_TYPE
6234 || TREE_CODE (constructor_type) == UNION_TYPE)
6235 constructor_unfilled_fields = next;
6236 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6238 TREE_INT_CST_LOW (constructor_unfilled_index)
6239 = TREE_INT_CST_LOW (next);
6240 TREE_INT_CST_HIGH (constructor_unfilled_index)
6241 = TREE_INT_CST_HIGH (next);
6245 /* ELT now points to the node in the pending tree with the next
6246 initializer to output. */
6250 /* Add one non-braced element to the current constructor level.
6251 This adjusts the current position within the constructor's type.
6252 This may also start or terminate implicit levels
6253 to handle a partly-braced initializer.
6255 Once this has found the correct level for the new element,
6256 it calls output_init_element.
6258 Note: if we are incrementally outputting this constructor,
6259 this function may be called with a null argument
6260 representing a sub-constructor that was already incrementally output.
6261 When that happens, we output nothing, but we do the bookkeeping
6262 to skip past that element of the current constructor. */
6265 process_init_element (value)
6268 tree orig_value = value;
6269 int string_flag = value != 0 && TREE_CODE (value) == STRING_CST;
6271 /* Handle superfluous braces around string cst as in
6272 char x[] = {"foo"}; */
6275 && TREE_CODE (constructor_type) == ARRAY_TYPE
6276 && TREE_CODE (TREE_TYPE (constructor_type)) == INTEGER_TYPE
6277 && integer_zerop (constructor_unfilled_index))
6279 if (constructor_stack->replacement_value)
6280 error_init ("excess elements in char array initializer");
6281 constructor_stack->replacement_value = value;
6285 if (constructor_stack->replacement_value != 0)
6287 error_init ("excess elements in struct initializer");
6291 /* Ignore elements of a brace group if it is entirely superfluous
6292 and has already been diagnosed. */
6293 if (constructor_type == 0)
6296 /* If we've exhausted any levels that didn't have braces,
6298 while (constructor_stack->implicit)
6300 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6301 || TREE_CODE (constructor_type) == UNION_TYPE)
6302 && constructor_fields == 0)
6303 process_init_element (pop_init_level (1));
6304 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6305 && (constructor_max_index == 0
6306 || tree_int_cst_lt (constructor_max_index,
6307 constructor_index)))
6308 process_init_element (pop_init_level (1));
6315 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6318 enum tree_code fieldcode;
6320 if (constructor_fields == 0)
6322 pedwarn_init ("excess elements in struct initializer");
6326 fieldtype = TREE_TYPE (constructor_fields);
6327 if (fieldtype != error_mark_node)
6328 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6329 fieldcode = TREE_CODE (fieldtype);
6331 /* Accept a string constant to initialize a subarray. */
6333 && fieldcode == ARRAY_TYPE
6334 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6337 /* Otherwise, if we have come to a subaggregate,
6338 and we don't have an element of its type, push into it. */
6339 else if (value != 0 && !constructor_no_implicit
6340 && value != error_mark_node
6341 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6342 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6343 || fieldcode == UNION_TYPE))
6345 push_init_level (1);
6351 push_member_name (constructor_fields);
6352 output_init_element (value, fieldtype, constructor_fields, 1);
6353 RESTORE_SPELLING_DEPTH (constructor_depth);
6356 /* Do the bookkeeping for an element that was
6357 directly output as a constructor. */
6359 /* For a record, keep track of end position of last field. */
6360 tree temp = size_binop (PLUS_EXPR,
6361 DECL_FIELD_BITPOS (constructor_fields),
6362 DECL_SIZE (constructor_fields));
6363 TREE_INT_CST_LOW (constructor_bit_index)
6364 = TREE_INT_CST_LOW (temp);
6365 TREE_INT_CST_HIGH (constructor_bit_index)
6366 = TREE_INT_CST_HIGH (temp);
6368 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6369 /* Skip any nameless bit fields. */
6370 while (constructor_unfilled_fields != 0
6371 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6372 && DECL_NAME (constructor_unfilled_fields) == 0)
6373 constructor_unfilled_fields =
6374 TREE_CHAIN (constructor_unfilled_fields);
6377 constructor_fields = TREE_CHAIN (constructor_fields);
6378 /* Skip any nameless bit fields at the beginning. */
6379 while (constructor_fields != 0
6380 && DECL_C_BIT_FIELD (constructor_fields)
6381 && DECL_NAME (constructor_fields) == 0)
6382 constructor_fields = TREE_CHAIN (constructor_fields);
6385 if (TREE_CODE (constructor_type) == UNION_TYPE)
6388 enum tree_code fieldcode;
6390 if (constructor_fields == 0)
6392 pedwarn_init ("excess elements in union initializer");
6396 fieldtype = TREE_TYPE (constructor_fields);
6397 if (fieldtype != error_mark_node)
6398 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6399 fieldcode = TREE_CODE (fieldtype);
6401 /* Accept a string constant to initialize a subarray. */
6403 && fieldcode == ARRAY_TYPE
6404 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6407 /* Otherwise, if we have come to a subaggregate,
6408 and we don't have an element of its type, push into it. */
6409 else if (value != 0 && !constructor_no_implicit
6410 && value != error_mark_node
6411 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6412 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6413 || fieldcode == UNION_TYPE))
6415 push_init_level (1);
6421 push_member_name (constructor_fields);
6422 output_init_element (value, fieldtype, constructor_fields, 1);
6423 RESTORE_SPELLING_DEPTH (constructor_depth);
6426 /* Do the bookkeeping for an element that was
6427 directly output as a constructor. */
6429 TREE_INT_CST_LOW (constructor_bit_index)
6430 = TREE_INT_CST_LOW (DECL_SIZE (constructor_fields));
6431 TREE_INT_CST_HIGH (constructor_bit_index)
6432 = TREE_INT_CST_HIGH (DECL_SIZE (constructor_fields));
6434 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6437 constructor_fields = 0;
6440 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6442 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6443 enum tree_code eltcode = TREE_CODE (elttype);
6445 /* Accept a string constant to initialize a subarray. */
6447 && eltcode == ARRAY_TYPE
6448 && TREE_CODE (TREE_TYPE (elttype)) == INTEGER_TYPE
6451 /* Otherwise, if we have come to a subaggregate,
6452 and we don't have an element of its type, push into it. */
6453 else if (value != 0 && !constructor_no_implicit
6454 && value != error_mark_node
6455 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != elttype
6456 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6457 || eltcode == UNION_TYPE))
6459 push_init_level (1);
6463 if (constructor_max_index != 0
6464 && tree_int_cst_lt (constructor_max_index, constructor_index))
6466 pedwarn_init ("excess elements in array initializer");
6470 /* In the case of [LO .. HI] = VALUE, only evaluate VALUE once. */
6471 if (constructor_range_end)
6473 if (constructor_max_index != 0
6474 && tree_int_cst_lt (constructor_max_index,
6475 constructor_range_end))
6477 pedwarn_init ("excess elements in array initializer");
6478 TREE_INT_CST_HIGH (constructor_range_end)
6479 = TREE_INT_CST_HIGH (constructor_max_index);
6480 TREE_INT_CST_LOW (constructor_range_end)
6481 = TREE_INT_CST_LOW (constructor_max_index);
6484 value = save_expr (value);
6487 /* Now output the actual element.
6488 Ordinarily, output once.
6489 If there is a range, repeat it till we advance past the range. */
6496 push_array_bounds (TREE_INT_CST_LOW (constructor_index));
6497 output_init_element (value, elttype, constructor_index, 1);
6498 RESTORE_SPELLING_DEPTH (constructor_depth);
6501 tem = size_binop (PLUS_EXPR, constructor_index,
6503 TREE_INT_CST_LOW (constructor_index) = TREE_INT_CST_LOW (tem);
6504 TREE_INT_CST_HIGH (constructor_index) = TREE_INT_CST_HIGH (tem);
6507 /* If we are doing the bookkeeping for an element that was
6508 directly output as a constructor,
6509 we must update constructor_unfilled_index. */
6511 TREE_INT_CST_LOW (constructor_unfilled_index)
6512 = TREE_INT_CST_LOW (constructor_index);
6513 TREE_INT_CST_HIGH (constructor_unfilled_index)
6514 = TREE_INT_CST_HIGH (constructor_index);
6517 while (! (constructor_range_end == 0
6518 || tree_int_cst_lt (constructor_range_end,
6519 constructor_index)));
6524 /* Handle the sole element allowed in a braced initializer
6525 for a scalar variable. */
6526 if (constructor_fields == 0)
6528 pedwarn_init ("excess elements in scalar initializer");
6533 output_init_element (value, constructor_type, NULL_TREE, 1);
6534 constructor_fields = 0;
6538 /* If the (lexically) previous elments are not now saved,
6539 we can discard the storage for them. */
6540 if (constructor_incremental && constructor_pending_elts == 0 && value != 0
6541 && constructor_stack == 0)
6545 /* Expand an ASM statement with operands, handling output operands
6546 that are not variables or INDIRECT_REFS by transforming such
6547 cases into cases that expand_asm_operands can handle.
6549 Arguments are same as for expand_asm_operands. */
6552 c_expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line)
6553 tree string, outputs, inputs, clobbers;
6558 int noutputs = list_length (outputs);
6560 /* o[I] is the place that output number I should be written. */
6561 register tree *o = (tree *) alloca (noutputs * sizeof (tree));
6564 if (TREE_CODE (string) == ADDR_EXPR)
6565 string = TREE_OPERAND (string, 0);
6566 if (TREE_CODE (string) != STRING_CST)
6568 error ("asm template is not a string constant");
6572 /* Record the contents of OUTPUTS before it is modified. */
6573 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6575 tree output = TREE_VALUE (tail);
6577 /* We can remove conversions that just change the type, not the mode. */
6578 STRIP_NOPS (output);
6581 /* Allow conversions as LHS here. build_modify_expr as called below
6582 will do the right thing with them. */
6583 while (TREE_CODE (output) == NOP_EXPR
6584 || TREE_CODE (output) == CONVERT_EXPR
6585 || TREE_CODE (output) == FLOAT_EXPR
6586 || TREE_CODE (output) == FIX_TRUNC_EXPR
6587 || TREE_CODE (output) == FIX_FLOOR_EXPR
6588 || TREE_CODE (output) == FIX_ROUND_EXPR
6589 || TREE_CODE (output) == FIX_CEIL_EXPR)
6590 output = TREE_OPERAND (output, 0);
6592 lvalue_or_else (o[i], "invalid lvalue in asm statement");
6595 /* Perform default conversions on array and function inputs. */
6596 /* Don't do this for other types--
6597 it would screw up operands expected to be in memory. */
6598 for (i = 0, tail = inputs; tail; tail = TREE_CHAIN (tail), i++)
6599 if (TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == ARRAY_TYPE
6600 || TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == FUNCTION_TYPE)
6601 TREE_VALUE (tail) = default_conversion (TREE_VALUE (tail));
6603 /* Generate the ASM_OPERANDS insn;
6604 store into the TREE_VALUEs of OUTPUTS some trees for
6605 where the values were actually stored. */
6606 expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line);
6608 /* Copy all the intermediate outputs into the specified outputs. */
6609 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6611 if (o[i] != TREE_VALUE (tail))
6613 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
6614 NULL_RTX, VOIDmode, EXPAND_NORMAL);
6617 /* Detect modification of read-only values.
6618 (Otherwise done by build_modify_expr.) */
6621 tree type = TREE_TYPE (o[i]);
6622 if (TREE_READONLY (o[i])
6623 || TYPE_READONLY (type)
6624 || ((TREE_CODE (type) == RECORD_TYPE
6625 || TREE_CODE (type) == UNION_TYPE)
6626 && C_TYPE_FIELDS_READONLY (type)))
6627 readonly_warning (o[i], "modification by `asm'");
6631 /* Those MODIFY_EXPRs could do autoincrements. */
6635 /* Expand a C `return' statement.
6636 RETVAL is the expression for what to return,
6637 or a null pointer for `return;' with no value. */
6640 c_expand_return (retval)
6643 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6645 if (TREE_THIS_VOLATILE (current_function_decl))
6646 warning ("function declared `noreturn' has a `return' statement");
6650 current_function_returns_null = 1;
6651 if (warn_return_type && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6652 warning ("`return' with no value, in function returning non-void");
6653 expand_null_return ();
6655 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6657 current_function_returns_null = 1;
6658 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6659 pedwarn ("`return' with a value, in function returning void");
6660 expand_return (retval);
6664 tree t = convert_for_assignment (valtype, retval, _("return"),
6665 NULL_TREE, NULL_TREE, 0);
6666 tree res = DECL_RESULT (current_function_decl);
6669 if (t == error_mark_node)
6672 inner = t = convert (TREE_TYPE (res), t);
6674 /* Strip any conversions, additions, and subtractions, and see if
6675 we are returning the address of a local variable. Warn if so. */
6678 switch (TREE_CODE (inner))
6680 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6682 inner = TREE_OPERAND (inner, 0);
6686 /* If the second operand of the MINUS_EXPR has a pointer
6687 type (or is converted from it), this may be valid, so
6688 don't give a warning. */
6690 tree op1 = TREE_OPERAND (inner, 1);
6692 while (! POINTER_TYPE_P (TREE_TYPE (op1))
6693 && (TREE_CODE (op1) == NOP_EXPR
6694 || TREE_CODE (op1) == NON_LVALUE_EXPR
6695 || TREE_CODE (op1) == CONVERT_EXPR))
6696 op1 = TREE_OPERAND (op1, 0);
6698 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6701 inner = TREE_OPERAND (inner, 0);
6706 inner = TREE_OPERAND (inner, 0);
6708 while (TREE_CODE_CLASS (TREE_CODE (inner)) == 'r')
6709 inner = TREE_OPERAND (inner, 0);
6711 if (TREE_CODE (inner) == VAR_DECL
6712 && ! DECL_EXTERNAL (inner)
6713 && ! TREE_STATIC (inner)
6714 && DECL_CONTEXT (inner) == current_function_decl)
6715 warning ("function returns address of local variable");
6725 t = build (MODIFY_EXPR, TREE_TYPE (res), res, t);
6726 TREE_SIDE_EFFECTS (t) = 1;
6728 current_function_returns_value = 1;
6732 /* Start a C switch statement, testing expression EXP.
6733 Return EXP if it is valid, an error node otherwise. */
6736 c_expand_start_case (exp)
6739 register enum tree_code code;
6742 if (TREE_CODE (exp) == ERROR_MARK)
6745 code = TREE_CODE (TREE_TYPE (exp));
6746 type = TREE_TYPE (exp);
6748 if (code != INTEGER_TYPE && code != ENUMERAL_TYPE && code != ERROR_MARK)
6750 error ("switch quantity not an integer");
6751 exp = error_mark_node;
6756 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6758 if (warn_traditional
6759 && ! in_system_header
6760 && (type == long_integer_type_node
6761 || type == long_unsigned_type_node))
6762 pedwarn ("`long' switch expression not converted to `int' in ANSI C");
6764 exp = default_conversion (exp);
6765 type = TREE_TYPE (exp);
6766 index = get_unwidened (exp, NULL_TREE);
6767 /* We can't strip a conversion from a signed type to an unsigned,
6768 because if we did, int_fits_type_p would do the wrong thing
6769 when checking case values for being in range,
6770 and it's too hard to do the right thing. */
6771 if (TREE_UNSIGNED (TREE_TYPE (exp))
6772 == TREE_UNSIGNED (TREE_TYPE (index)))
6776 expand_start_case (1, exp, type, "switch statement");