1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
23 /* This file is part of the C front end.
24 It contains routines to build C expressions given their operands,
25 including computing the types of the result, C-specific error checks,
26 and some optimization.
28 There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
29 and to process initializations in declarations (since they work
30 like a strange sort of assignment). */
46 /* Nonzero if we've already printed a "missing braces around initializer"
47 message within this initializer. */
48 static int missing_braces_mentioned;
50 /* 1 if we explained undeclared var errors. */
51 static int undeclared_variable_notice;
53 static tree qualify_type PARAMS ((tree, tree));
54 static int comp_target_types PARAMS ((tree, tree));
55 static int function_types_compatible_p PARAMS ((tree, tree));
56 static int type_lists_compatible_p PARAMS ((tree, tree));
57 static tree decl_constant_value_for_broken_optimization PARAMS ((tree));
58 static tree lookup_field PARAMS ((tree, tree, tree *));
59 static tree convert_arguments PARAMS ((tree, tree, tree, tree));
60 static tree pointer_int_sum PARAMS ((enum tree_code, tree, tree));
61 static tree pointer_diff PARAMS ((tree, tree));
62 static tree unary_complex_lvalue PARAMS ((enum tree_code, tree));
63 static void pedantic_lvalue_warning PARAMS ((enum tree_code));
64 static tree internal_build_compound_expr PARAMS ((tree, int));
65 static tree convert_for_assignment PARAMS ((tree, tree, const char *,
67 static void warn_for_assignment PARAMS ((const char *, const char *,
69 static tree valid_compound_expr_initializer PARAMS ((tree, tree));
70 static void push_string PARAMS ((const char *));
71 static void push_member_name PARAMS ((tree));
72 static void push_array_bounds PARAMS ((int));
73 static int spelling_length PARAMS ((void));
74 static char *print_spelling PARAMS ((char *));
75 static void warning_init PARAMS ((const char *));
76 static tree digest_init PARAMS ((tree, tree, int, int));
77 static void output_init_element PARAMS ((tree, tree, tree, int));
78 static void output_pending_init_elements PARAMS ((int));
79 static void add_pending_init PARAMS ((tree, tree));
80 static int pending_init_member PARAMS ((tree));
82 /* Do `exp = require_complete_type (exp);' to make sure exp
83 does not have an incomplete type. (That includes void types.) */
86 require_complete_type (value)
89 tree type = TREE_TYPE (value);
91 if (TREE_CODE (value) == ERROR_MARK)
92 return error_mark_node;
94 /* First, detect a valid value with a complete type. */
95 if (COMPLETE_TYPE_P (type))
98 incomplete_type_error (value, type);
99 return error_mark_node;
102 /* Print an error message for invalid use of an incomplete type.
103 VALUE is the expression that was used (or 0 if that isn't known)
104 and TYPE is the type that was invalid. */
107 incomplete_type_error (value, type)
111 const char *type_code_string;
113 /* Avoid duplicate error message. */
114 if (TREE_CODE (type) == ERROR_MARK)
117 if (value != 0 && (TREE_CODE (value) == VAR_DECL
118 || TREE_CODE (value) == PARM_DECL))
119 error ("`%s' has an incomplete type",
120 IDENTIFIER_POINTER (DECL_NAME (value)));
124 /* We must print an error message. Be clever about what it says. */
126 switch (TREE_CODE (type))
129 type_code_string = "struct";
133 type_code_string = "union";
137 type_code_string = "enum";
141 error ("invalid use of void expression");
145 if (TYPE_DOMAIN (type))
147 type = TREE_TYPE (type);
150 error ("invalid use of array with unspecified bounds");
157 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
158 error ("invalid use of undefined type `%s %s'",
159 type_code_string, IDENTIFIER_POINTER (TYPE_NAME (type)));
161 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
162 error ("invalid use of incomplete typedef `%s'",
163 IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
167 /* Return a variant of TYPE which has all the type qualifiers of LIKE
168 as well as those of TYPE. */
171 qualify_type (type, like)
174 return c_build_qualified_type (type,
175 TYPE_QUALS (type) | TYPE_QUALS (like));
178 /* Return the common type of two types.
179 We assume that comptypes has already been done and returned 1;
180 if that isn't so, this may crash. In particular, we assume that qualifiers
183 This is the type for the result of most arithmetic operations
184 if the operands have the given two types. */
190 register enum tree_code code1;
191 register enum tree_code code2;
194 /* Save time if the two types are the same. */
196 if (t1 == t2) return t1;
198 /* If one type is nonsense, use the other. */
199 if (t1 == error_mark_node)
201 if (t2 == error_mark_node)
204 /* Merge the attributes. */
205 attributes = merge_machine_type_attributes (t1, t2);
207 /* Treat an enum type as the unsigned integer type of the same width. */
209 if (TREE_CODE (t1) == ENUMERAL_TYPE)
210 t1 = type_for_size (TYPE_PRECISION (t1), 1);
211 if (TREE_CODE (t2) == ENUMERAL_TYPE)
212 t2 = type_for_size (TYPE_PRECISION (t2), 1);
214 code1 = TREE_CODE (t1);
215 code2 = TREE_CODE (t2);
217 /* If one type is complex, form the common type of the non-complex
218 components, then make that complex. Use T1 or T2 if it is the
220 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
222 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
223 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
224 tree subtype = common_type (subtype1, subtype2);
226 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
227 return build_type_attribute_variant (t1, attributes);
228 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
229 return build_type_attribute_variant (t2, attributes);
231 return build_type_attribute_variant (build_complex_type (subtype),
239 /* If only one is real, use it as the result. */
241 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
242 return build_type_attribute_variant (t1, attributes);
244 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
245 return build_type_attribute_variant (t2, attributes);
247 /* Both real or both integers; use the one with greater precision. */
249 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
250 return build_type_attribute_variant (t1, attributes);
251 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
252 return build_type_attribute_variant (t2, attributes);
254 /* Same precision. Prefer longs to ints even when same size. */
256 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
257 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
258 return build_type_attribute_variant (long_unsigned_type_node,
261 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
262 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
264 /* But preserve unsignedness from the other type,
265 since long cannot hold all the values of an unsigned int. */
266 if (TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
267 t1 = long_unsigned_type_node;
269 t1 = long_integer_type_node;
270 return build_type_attribute_variant (t1, attributes);
273 /* Likewise, prefer long double to double even if same size. */
274 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
275 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
276 return build_type_attribute_variant (long_double_type_node,
279 /* Otherwise prefer the unsigned one. */
281 if (TREE_UNSIGNED (t1))
282 return build_type_attribute_variant (t1, attributes);
284 return build_type_attribute_variant (t2, attributes);
287 /* For two pointers, do this recursively on the target type,
288 and combine the qualifiers of the two types' targets. */
289 /* This code was turned off; I don't know why.
290 But ANSI C specifies doing this with the qualifiers.
291 So I turned it on again. */
293 tree pointed_to_1 = TREE_TYPE (t1);
294 tree pointed_to_2 = TREE_TYPE (t2);
295 tree target = common_type (TYPE_MAIN_VARIANT (pointed_to_1),
296 TYPE_MAIN_VARIANT (pointed_to_2));
297 t1 = build_pointer_type (c_build_qualified_type
299 TYPE_QUALS (pointed_to_1) |
300 TYPE_QUALS (pointed_to_2)));
301 return build_type_attribute_variant (t1, attributes);
304 t1 = build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2)));
305 return build_type_attribute_variant (t1, attributes);
310 tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
311 /* Save space: see if the result is identical to one of the args. */
312 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
313 return build_type_attribute_variant (t1, attributes);
314 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
315 return build_type_attribute_variant (t2, attributes);
316 /* Merge the element types, and have a size if either arg has one. */
317 t1 = build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
318 return build_type_attribute_variant (t1, attributes);
322 /* Function types: prefer the one that specified arg types.
323 If both do, merge the arg types. Also merge the return types. */
325 tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
326 tree p1 = TYPE_ARG_TYPES (t1);
327 tree p2 = TYPE_ARG_TYPES (t2);
332 /* Save space: see if the result is identical to one of the args. */
333 if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2))
334 return build_type_attribute_variant (t1, attributes);
335 if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1))
336 return build_type_attribute_variant (t2, attributes);
338 /* Simple way if one arg fails to specify argument types. */
339 if (TYPE_ARG_TYPES (t1) == 0)
341 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
342 return build_type_attribute_variant (t1, attributes);
344 if (TYPE_ARG_TYPES (t2) == 0)
346 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
347 return build_type_attribute_variant (t1, attributes);
350 /* If both args specify argument types, we must merge the two
351 lists, argument by argument. */
353 len = list_length (p1);
356 for (i = 0; i < len; i++)
357 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
362 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
364 /* A null type means arg type is not specified.
365 Take whatever the other function type has. */
366 if (TREE_VALUE (p1) == 0)
368 TREE_VALUE (n) = TREE_VALUE (p2);
371 if (TREE_VALUE (p2) == 0)
373 TREE_VALUE (n) = TREE_VALUE (p1);
377 /* Given wait (union {union wait *u; int *i} *)
378 and wait (union wait *),
379 prefer union wait * as type of parm. */
380 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
381 && TREE_VALUE (p1) != TREE_VALUE (p2))
384 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
385 memb; memb = TREE_CHAIN (memb))
386 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2)))
388 TREE_VALUE (n) = TREE_VALUE (p2);
390 pedwarn ("function types not truly compatible in ISO C");
394 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
395 && TREE_VALUE (p2) != TREE_VALUE (p1))
398 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
399 memb; memb = TREE_CHAIN (memb))
400 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1)))
402 TREE_VALUE (n) = TREE_VALUE (p1);
404 pedwarn ("function types not truly compatible in ISO C");
408 TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2));
412 t1 = build_function_type (valtype, newargs);
413 /* ... falls through ... */
417 return build_type_attribute_variant (t1, attributes);
422 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
423 or various other operations. Return 2 if they are compatible
424 but a warning may be needed if you use them together. */
427 comptypes (type1, type2)
430 register tree t1 = type1;
431 register tree t2 = type2;
434 /* Suppress errors caused by previously reported errors. */
436 if (t1 == t2 || !t1 || !t2
437 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
440 /* If either type is the internal version of sizetype, return the
442 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
443 && TYPE_DOMAIN (t1) != 0)
444 t1 = TYPE_DOMAIN (t1);
446 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
447 && TYPE_DOMAIN (t2) != 0)
448 t2 = TYPE_DOMAIN (t2);
450 /* Treat an enum type as the integer type of the same width and
453 if (TREE_CODE (t1) == ENUMERAL_TYPE)
454 t1 = type_for_size (TYPE_PRECISION (t1), TREE_UNSIGNED (t1));
455 if (TREE_CODE (t2) == ENUMERAL_TYPE)
456 t2 = type_for_size (TYPE_PRECISION (t2), TREE_UNSIGNED (t2));
461 /* Different classes of types can't be compatible. */
463 if (TREE_CODE (t1) != TREE_CODE (t2)) return 0;
465 /* Qualifiers must match. */
467 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
470 /* Allow for two different type nodes which have essentially the same
471 definition. Note that we already checked for equality of the type
472 qualifiers (just above). */
474 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
477 #ifndef COMP_TYPE_ATTRIBUTES
478 #define COMP_TYPE_ATTRIBUTES(t1,t2) 1
481 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
482 if (! (attrval = COMP_TYPE_ATTRIBUTES (t1, t2)))
485 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
488 switch (TREE_CODE (t1))
491 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
492 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
496 val = function_types_compatible_p (t1, t2);
501 tree d1 = TYPE_DOMAIN (t1);
502 tree d2 = TYPE_DOMAIN (t2);
505 /* Target types must match incl. qualifiers. */
506 if (TREE_TYPE (t1) != TREE_TYPE (t2)
507 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
510 /* Sizes must match unless one is missing or variable. */
511 if (d1 == 0 || d2 == 0 || d1 == d2
512 || TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
513 || TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
514 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST
515 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)
518 if (! tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
519 || ! tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
526 if (maybe_objc_comptypes (t1, t2, 0) == 1)
533 return attrval == 2 && val == 1 ? 2 : val;
536 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
537 ignoring their qualifiers. */
540 comp_target_types (ttl, ttr)
545 /* Give maybe_objc_comptypes a crack at letting these types through. */
546 if ((val = maybe_objc_comptypes (ttl, ttr, 1)) >= 0)
549 val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)),
550 TYPE_MAIN_VARIANT (TREE_TYPE (ttr)));
552 if (val == 2 && pedantic)
553 pedwarn ("types are not quite compatible");
557 /* Subroutines of `comptypes'. */
559 /* Return 1 if two function types F1 and F2 are compatible.
560 If either type specifies no argument types,
561 the other must specify a fixed number of self-promoting arg types.
562 Otherwise, if one type specifies only the number of arguments,
563 the other must specify that number of self-promoting arg types.
564 Otherwise, the argument types must match. */
567 function_types_compatible_p (f1, f2)
571 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
575 if (!(TREE_TYPE (f1) == TREE_TYPE (f2)
576 || (val = comptypes (TREE_TYPE (f1), TREE_TYPE (f2)))))
579 args1 = TYPE_ARG_TYPES (f1);
580 args2 = TYPE_ARG_TYPES (f2);
582 /* An unspecified parmlist matches any specified parmlist
583 whose argument types don't need default promotions. */
587 if (!self_promoting_args_p (args2))
589 /* If one of these types comes from a non-prototype fn definition,
590 compare that with the other type's arglist.
591 If they don't match, ask for a warning (but no error). */
592 if (TYPE_ACTUAL_ARG_TYPES (f1)
593 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
599 if (!self_promoting_args_p (args1))
601 if (TYPE_ACTUAL_ARG_TYPES (f2)
602 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
607 /* Both types have argument lists: compare them and propagate results. */
608 val1 = type_lists_compatible_p (args1, args2);
609 return val1 != 1 ? val1 : val;
612 /* Check two lists of types for compatibility,
613 returning 0 for incompatible, 1 for compatible,
614 or 2 for compatible with warning. */
617 type_lists_compatible_p (args1, args2)
620 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
626 if (args1 == 0 && args2 == 0)
628 /* If one list is shorter than the other,
629 they fail to match. */
630 if (args1 == 0 || args2 == 0)
632 /* A null pointer instead of a type
633 means there is supposed to be an argument
634 but nothing is specified about what type it has.
635 So match anything that self-promotes. */
636 if (TREE_VALUE (args1) == 0)
638 if (simple_type_promotes_to (TREE_VALUE (args2)) != NULL_TREE)
641 else if (TREE_VALUE (args2) == 0)
643 if (simple_type_promotes_to (TREE_VALUE (args1)) != NULL_TREE)
646 else if (! (newval = comptypes (TREE_VALUE (args1), TREE_VALUE (args2))))
648 /* Allow wait (union {union wait *u; int *i} *)
649 and wait (union wait *) to be compatible. */
650 if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE
651 && (TYPE_NAME (TREE_VALUE (args1)) == 0
652 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args1)))
653 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST
654 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)),
655 TYPE_SIZE (TREE_VALUE (args2))))
658 for (memb = TYPE_FIELDS (TREE_VALUE (args1));
659 memb; memb = TREE_CHAIN (memb))
660 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2)))
665 else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE
666 && (TYPE_NAME (TREE_VALUE (args2)) == 0
667 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args2)))
668 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST
669 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)),
670 TYPE_SIZE (TREE_VALUE (args1))))
673 for (memb = TYPE_FIELDS (TREE_VALUE (args2));
674 memb; memb = TREE_CHAIN (memb))
675 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1)))
684 /* comptypes said ok, but record if it said to warn. */
688 args1 = TREE_CHAIN (args1);
689 args2 = TREE_CHAIN (args2);
693 /* Compute the value of the `sizeof' operator. */
699 enum tree_code code = TREE_CODE (type);
702 if (code == FUNCTION_TYPE)
704 if (pedantic || warn_pointer_arith)
705 pedwarn ("sizeof applied to a function type");
706 size = size_one_node;
708 else if (code == VOID_TYPE)
710 if (pedantic || warn_pointer_arith)
711 pedwarn ("sizeof applied to a void type");
712 size = size_one_node;
714 else if (code == ERROR_MARK)
715 size = size_one_node;
716 else if (!COMPLETE_TYPE_P (type))
718 error ("sizeof applied to an incomplete type");
719 size = size_zero_node;
722 /* Convert in case a char is more than one unit. */
723 size = size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
724 size_int (TYPE_PRECISION (char_type_node)
727 /* SIZE will have an integer type with TYPE_IS_SIZETYPE set.
728 TYPE_IS_SIZETYPE means that certain things (like overflow) will
729 never happen. However, this node should really have type
730 `size_t', which is just a typedef for an ordinary integer type. */
731 return fold (build1 (NOP_EXPR, c_size_type_node, size));
735 c_sizeof_nowarn (type)
738 enum tree_code code = TREE_CODE (type);
741 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
742 size = size_one_node;
743 else if (!COMPLETE_TYPE_P (type))
744 size = size_zero_node;
746 /* Convert in case a char is more than one unit. */
747 size = size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
748 size_int (TYPE_PRECISION (char_type_node)
751 /* SIZE will have an integer type with TYPE_IS_SIZETYPE set.
752 TYPE_IS_SIZETYPE means that certain things (like overflow) will
753 never happen. However, this node should really have type
754 `size_t', which is just a typedef for an ordinary integer type. */
755 return fold (build1 (NOP_EXPR, c_size_type_node, size));
758 /* Compute the size to increment a pointer by. */
761 c_size_in_bytes (type)
764 enum tree_code code = TREE_CODE (type);
766 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
767 return size_one_node;
769 if (!COMPLETE_OR_VOID_TYPE_P (type))
771 error ("arithmetic on pointer to an incomplete type");
772 return size_one_node;
775 /* Convert in case a char is more than one unit. */
776 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
777 size_int (TYPE_PRECISION (char_type_node)
781 /* Implement the __alignof keyword: Return the minimum required
782 alignment of TYPE, measured in bytes. */
788 enum tree_code code = TREE_CODE (type);
791 if (code == FUNCTION_TYPE)
792 t = size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
793 else if (code == VOID_TYPE || code == ERROR_MARK)
795 else if (code == ERROR_MARK)
797 else if (!COMPLETE_TYPE_P (type))
799 error ("__alignof__ applied to an incomplete type");
803 t = size_int (TYPE_ALIGN (type) / BITS_PER_UNIT);
805 return fold (build1 (NOP_EXPR, c_size_type_node, t));
808 /* Implement the __alignof keyword: Return the minimum required
809 alignment of EXPR, measured in bytes. For VAR_DECL's and
810 FIELD_DECL's return DECL_ALIGN (which can be set from an
811 "aligned" __attribute__ specification). */
814 c_alignof_expr (expr)
819 if (TREE_CODE (expr) == VAR_DECL)
820 t = size_int (DECL_ALIGN (expr) / BITS_PER_UNIT);
822 else if (TREE_CODE (expr) == COMPONENT_REF
823 && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1)))
825 error ("`__alignof' applied to a bit-field");
828 else if (TREE_CODE (expr) == COMPONENT_REF
829 && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
830 t = size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT);
832 else if (TREE_CODE (expr) == INDIRECT_REF)
834 tree t = TREE_OPERAND (expr, 0);
836 int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
838 while (TREE_CODE (t) == NOP_EXPR
839 && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
843 t = TREE_OPERAND (t, 0);
844 thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
845 if (thisalign > bestalign)
846 best = t, bestalign = thisalign;
848 return c_alignof (TREE_TYPE (TREE_TYPE (best)));
851 return c_alignof (TREE_TYPE (expr));
853 return fold (build1 (NOP_EXPR, c_size_type_node, t));
856 /* Return either DECL or its known constant value (if it has one). */
859 decl_constant_value (decl)
862 if (/* Don't change a variable array bound or initial value to a constant
863 in a place where a variable is invalid. */
864 current_function_decl != 0
865 && ! TREE_THIS_VOLATILE (decl)
866 && TREE_READONLY (decl)
867 && DECL_INITIAL (decl) != 0
868 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
869 /* This is invalid if initial value is not constant.
870 If it has either a function call, a memory reference,
871 or a variable, then re-evaluating it could give different results. */
872 && TREE_CONSTANT (DECL_INITIAL (decl))
873 /* Check for cases where this is sub-optimal, even though valid. */
874 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
875 return DECL_INITIAL (decl);
879 /* Return either DECL or its known constant value (if it has one), but
880 return DECL if pedantic or DECL has mode BLKmode. This is for
881 bug-compatibility with the old behavior of decl_constant_value
882 (before GCC 3.0); every use of this function is a bug and it should
883 be removed before GCC 3.1. It is not appropriate to use pedantic
884 in a way that affects optimization, and BLKmode is probably not the
885 right test for avoiding misoptimizations either. */
888 decl_constant_value_for_broken_optimization (decl)
891 if (pedantic || DECL_MODE (decl) == BLKmode)
894 return decl_constant_value (decl);
897 /* Perform default promotions for C data used in expressions.
898 Arrays and functions are converted to pointers;
899 enumeral types or short or char, to int.
900 In addition, manifest constants symbols are replaced by their values. */
903 default_conversion (exp)
906 register tree type = TREE_TYPE (exp);
907 register enum tree_code code = TREE_CODE (type);
909 /* Constants can be used directly unless they're not loadable. */
910 if (TREE_CODE (exp) == CONST_DECL)
911 exp = DECL_INITIAL (exp);
913 /* Replace a nonvolatile const static variable with its value unless
914 it is an array, in which case we must be sure that taking the
915 address of the array produces consistent results. */
916 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
918 exp = decl_constant_value_for_broken_optimization (exp);
919 type = TREE_TYPE (exp);
922 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
925 Do not use STRIP_NOPS here! It will remove conversions from pointer
926 to integer and cause infinite recursion. */
927 while (TREE_CODE (exp) == NON_LVALUE_EXPR
928 || (TREE_CODE (exp) == NOP_EXPR
929 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
930 exp = TREE_OPERAND (exp, 0);
932 /* Normally convert enums to int,
933 but convert wide enums to something wider. */
934 if (code == ENUMERAL_TYPE)
936 type = type_for_size (MAX (TYPE_PRECISION (type),
937 TYPE_PRECISION (integer_type_node)),
939 || (TYPE_PRECISION (type)
940 >= TYPE_PRECISION (integer_type_node)))
941 && TREE_UNSIGNED (type)));
943 return convert (type, exp);
946 if (TREE_CODE (exp) == COMPONENT_REF
947 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
948 /* If it's thinner than an int, promote it like a
949 C_PROMOTING_INTEGER_TYPE_P, otherwise leave it alone. */
950 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
951 TYPE_PRECISION (integer_type_node)))
952 return convert (flag_traditional && TREE_UNSIGNED (type)
953 ? unsigned_type_node : integer_type_node,
956 if (C_PROMOTING_INTEGER_TYPE_P (type))
958 /* Traditionally, unsignedness is preserved in default promotions.
959 Also preserve unsignedness if not really getting any wider. */
960 if (TREE_UNSIGNED (type)
962 || TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
963 return convert (unsigned_type_node, exp);
965 return convert (integer_type_node, exp);
968 if (code == BOOLEAN_TYPE)
969 return convert (integer_type_node, exp);
971 if (flag_traditional && !flag_allow_single_precision
972 && TYPE_MAIN_VARIANT (type) == float_type_node)
973 return convert (double_type_node, exp);
975 if (code == VOID_TYPE)
977 error ("void value not ignored as it ought to be");
978 return error_mark_node;
980 if (code == FUNCTION_TYPE)
982 return build_unary_op (ADDR_EXPR, exp, 0);
984 if (code == ARRAY_TYPE)
987 tree restype = TREE_TYPE (type);
992 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r' || DECL_P (exp))
994 constp = TREE_READONLY (exp);
995 volatilep = TREE_THIS_VOLATILE (exp);
998 if (TYPE_QUALS (type) || constp || volatilep)
1000 = c_build_qualified_type (restype,
1002 | (constp * TYPE_QUAL_CONST)
1003 | (volatilep * TYPE_QUAL_VOLATILE));
1005 if (TREE_CODE (exp) == INDIRECT_REF)
1006 return convert (TYPE_POINTER_TO (restype),
1007 TREE_OPERAND (exp, 0));
1009 if (TREE_CODE (exp) == COMPOUND_EXPR)
1011 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
1012 return build (COMPOUND_EXPR, TREE_TYPE (op1),
1013 TREE_OPERAND (exp, 0), op1);
1016 if (! lvalue_p (exp)
1017 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1019 error ("invalid use of non-lvalue array");
1020 return error_mark_node;
1023 ptrtype = build_pointer_type (restype);
1025 if (TREE_CODE (exp) == VAR_DECL)
1027 /* ??? This is not really quite correct
1028 in that the type of the operand of ADDR_EXPR
1029 is not the target type of the type of the ADDR_EXPR itself.
1030 Question is, can this lossage be avoided? */
1031 adr = build1 (ADDR_EXPR, ptrtype, exp);
1032 if (mark_addressable (exp) == 0)
1033 return error_mark_node;
1034 TREE_CONSTANT (adr) = staticp (exp);
1035 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1038 /* This way is better for a COMPONENT_REF since it can
1039 simplify the offset for a component. */
1040 adr = build_unary_op (ADDR_EXPR, exp, 1);
1041 return convert (ptrtype, adr);
1046 /* Look up component name in the structure type definition.
1048 If this component name is found indirectly within an anonymous union,
1049 store in *INDIRECT the component which directly contains
1050 that anonymous union. Otherwise, set *INDIRECT to 0. */
1053 lookup_field (type, component, indirect)
1054 tree type, component;
1059 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1060 to the field elements. Use a binary search on this array to quickly
1061 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1062 will always be set for structures which have many elements. */
1064 if (TYPE_LANG_SPECIFIC (type))
1067 tree *field_array = &TYPE_LANG_SPECIFIC (type)->elts[0];
1069 field = TYPE_FIELDS (type);
1071 top = TYPE_LANG_SPECIFIC (type)->len;
1072 while (top - bot > 1)
1074 half = (top - bot + 1) >> 1;
1075 field = field_array[bot+half];
1077 if (DECL_NAME (field) == NULL_TREE)
1079 /* Step through all anon unions in linear fashion. */
1080 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1082 tree anon = 0, junk;
1084 field = field_array[bot++];
1085 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1086 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1087 anon = lookup_field (TREE_TYPE (field), component, &junk);
1089 if (anon != NULL_TREE)
1096 /* Entire record is only anon unions. */
1100 /* Restart the binary search, with new lower bound. */
1104 if (DECL_NAME (field) == component)
1106 if (DECL_NAME (field) < component)
1112 if (DECL_NAME (field_array[bot]) == component)
1113 field = field_array[bot];
1114 else if (DECL_NAME (field) != component)
1119 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1121 if (DECL_NAME (field) == NULL_TREE)
1126 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1127 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1128 anon = lookup_field (TREE_TYPE (field), component, &junk);
1130 if (anon != NULL_TREE)
1137 if (DECL_NAME (field) == component)
1142 *indirect = NULL_TREE;
1146 /* Make an expression to refer to the COMPONENT field of
1147 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1150 build_component_ref (datum, component)
1151 tree datum, component;
1153 register tree type = TREE_TYPE (datum);
1154 register enum tree_code code = TREE_CODE (type);
1155 register tree field = NULL;
1158 /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it
1159 unless we are not to support things not strictly ANSI. */
1160 switch (TREE_CODE (datum))
1164 tree value = build_component_ref (TREE_OPERAND (datum, 1), component);
1165 return build (COMPOUND_EXPR, TREE_TYPE (value),
1166 TREE_OPERAND (datum, 0), value);
1169 return build_conditional_expr
1170 (TREE_OPERAND (datum, 0),
1171 build_component_ref (TREE_OPERAND (datum, 1), component),
1172 build_component_ref (TREE_OPERAND (datum, 2), component));
1178 /* See if there is a field or component with name COMPONENT. */
1180 if (code == RECORD_TYPE || code == UNION_TYPE)
1184 if (!COMPLETE_TYPE_P (type))
1186 incomplete_type_error (NULL_TREE, type);
1187 return error_mark_node;
1190 field = lookup_field (type, component, &indirect);
1194 error ("%s has no member named `%s'",
1195 code == RECORD_TYPE ? "structure" : "union",
1196 IDENTIFIER_POINTER (component));
1197 return error_mark_node;
1199 if (TREE_TYPE (field) == error_mark_node)
1200 return error_mark_node;
1202 /* If FIELD was found buried within an anonymous union,
1203 make one COMPONENT_REF to get that anonymous union,
1204 then fall thru to make a second COMPONENT_REF to get FIELD. */
1207 ref = build (COMPONENT_REF, TREE_TYPE (indirect), datum, indirect);
1208 if (TREE_READONLY (datum) || TREE_READONLY (indirect))
1209 TREE_READONLY (ref) = 1;
1210 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (indirect))
1211 TREE_THIS_VOLATILE (ref) = 1;
1215 ref = build (COMPONENT_REF, TREE_TYPE (field), datum, field);
1217 if (TREE_READONLY (datum) || TREE_READONLY (field))
1218 TREE_READONLY (ref) = 1;
1219 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (field))
1220 TREE_THIS_VOLATILE (ref) = 1;
1224 else if (code != ERROR_MARK)
1225 error ("request for member `%s' in something not a structure or union",
1226 IDENTIFIER_POINTER (component));
1228 return error_mark_node;
1231 /* Given an expression PTR for a pointer, return an expression
1232 for the value pointed to.
1233 ERRORSTRING is the name of the operator to appear in error messages. */
1236 build_indirect_ref (ptr, errorstring)
1238 const char *errorstring;
1240 register tree pointer = default_conversion (ptr);
1241 register tree type = TREE_TYPE (pointer);
1243 if (TREE_CODE (type) == POINTER_TYPE)
1245 if (TREE_CODE (pointer) == ADDR_EXPR
1247 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1248 == TREE_TYPE (type)))
1249 return TREE_OPERAND (pointer, 0);
1252 tree t = TREE_TYPE (type);
1253 register tree ref = build1 (INDIRECT_REF,
1254 TYPE_MAIN_VARIANT (t), pointer);
1256 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1258 error ("dereferencing pointer to incomplete type");
1259 return error_mark_node;
1261 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1262 warning ("dereferencing `void *' pointer");
1264 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1265 so that we get the proper error message if the result is used
1266 to assign to. Also, &* is supposed to be a no-op.
1267 And ANSI C seems to specify that the type of the result
1268 should be the const type. */
1269 /* A de-reference of a pointer to const is not a const. It is valid
1270 to change it via some other pointer. */
1271 TREE_READONLY (ref) = TYPE_READONLY (t);
1272 TREE_SIDE_EFFECTS (ref)
1273 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer) || flag_volatile;
1274 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1278 else if (TREE_CODE (pointer) != ERROR_MARK)
1279 error ("invalid type argument of `%s'", errorstring);
1280 return error_mark_node;
1283 /* This handles expressions of the form "a[i]", which denotes
1286 This is logically equivalent in C to *(a+i), but we may do it differently.
1287 If A is a variable or a member, we generate a primitive ARRAY_REF.
1288 This avoids forcing the array out of registers, and can work on
1289 arrays that are not lvalues (for example, members of structures returned
1293 build_array_ref (array, index)
1298 error ("subscript missing in array reference");
1299 return error_mark_node;
1302 if (TREE_TYPE (array) == error_mark_node
1303 || TREE_TYPE (index) == error_mark_node)
1304 return error_mark_node;
1306 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
1307 && TREE_CODE (array) != INDIRECT_REF)
1311 /* Subscripting with type char is likely to lose
1312 on a machine where chars are signed.
1313 So warn on any machine, but optionally.
1314 Don't warn for unsigned char since that type is safe.
1315 Don't warn for signed char because anyone who uses that
1316 must have done so deliberately. */
1317 if (warn_char_subscripts
1318 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1319 warning ("array subscript has type `char'");
1321 /* Apply default promotions *after* noticing character types. */
1322 index = default_conversion (index);
1324 /* Require integer *after* promotion, for sake of enums. */
1325 if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE)
1327 error ("array subscript is not an integer");
1328 return error_mark_node;
1331 /* An array that is indexed by a non-constant
1332 cannot be stored in a register; we must be able to do
1333 address arithmetic on its address.
1334 Likewise an array of elements of variable size. */
1335 if (TREE_CODE (index) != INTEGER_CST
1336 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1337 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1339 if (mark_addressable (array) == 0)
1340 return error_mark_node;
1342 /* An array that is indexed by a constant value which is not within
1343 the array bounds cannot be stored in a register either; because we
1344 would get a crash in store_bit_field/extract_bit_field when trying
1345 to access a non-existent part of the register. */
1346 if (TREE_CODE (index) == INTEGER_CST
1347 && TYPE_VALUES (TREE_TYPE (array))
1348 && ! int_fits_type_p (index, TYPE_VALUES (TREE_TYPE (array))))
1350 if (mark_addressable (array) == 0)
1351 return error_mark_node;
1357 while (TREE_CODE (foo) == COMPONENT_REF)
1358 foo = TREE_OPERAND (foo, 0);
1359 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
1360 pedwarn ("ISO C forbids subscripting `register' array");
1361 else if (! flag_isoc99 && ! lvalue_p (foo))
1362 pedwarn ("ISO C89 forbids subscripting non-lvalue array");
1365 type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array)));
1366 rval = build (ARRAY_REF, type, array, index);
1367 /* Array ref is const/volatile if the array elements are
1368 or if the array is. */
1369 TREE_READONLY (rval)
1370 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1371 | TREE_READONLY (array));
1372 TREE_SIDE_EFFECTS (rval)
1373 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1374 | TREE_SIDE_EFFECTS (array));
1375 TREE_THIS_VOLATILE (rval)
1376 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1377 /* This was added by rms on 16 Nov 91.
1378 It fixes vol struct foo *a; a->elts[1]
1379 in an inline function.
1380 Hope it doesn't break something else. */
1381 | TREE_THIS_VOLATILE (array));
1382 return require_complete_type (fold (rval));
1386 tree ar = default_conversion (array);
1387 tree ind = default_conversion (index);
1389 /* Do the same warning check as above, but only on the part that's
1390 syntactically the index and only if it is also semantically
1392 if (warn_char_subscripts
1393 && TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE
1394 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1395 warning ("subscript has type `char'");
1397 /* Put the integer in IND to simplify error checking. */
1398 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
1405 if (ar == error_mark_node)
1408 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE
1409 || TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) == FUNCTION_TYPE)
1411 error ("subscripted value is neither array nor pointer");
1412 return error_mark_node;
1414 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
1416 error ("array subscript is not an integer");
1417 return error_mark_node;
1420 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0),
1425 /* Build an external reference to identifier ID. FUN indicates
1426 whether this will be used for a function call. */
1428 build_external_ref (id, fun)
1433 tree decl = lookup_name (id);
1434 tree objc_ivar = lookup_objc_ivar (id);
1436 if (!decl || decl == error_mark_node || C_DECL_ANTICIPATED (decl))
1442 if (!decl || decl == error_mark_node)
1443 /* Ordinary implicit function declaration. */
1444 ref = implicitly_declare (id);
1447 /* Implicit declaration of built-in function. Don't
1448 change the built-in declaration, but don't let this
1449 go by silently, either. */
1450 implicit_decl_warning (id);
1452 /* only issue this warning once */
1453 C_DECL_ANTICIPATED (decl) = 0;
1459 /* Reference to undeclared variable, including reference to
1460 builtin outside of function-call context. */
1461 if (current_function_decl == 0)
1462 error ("`%s' undeclared here (not in a function)",
1463 IDENTIFIER_POINTER (id));
1466 if (IDENTIFIER_GLOBAL_VALUE (id) != error_mark_node
1467 || IDENTIFIER_ERROR_LOCUS (id) != current_function_decl)
1469 error ("`%s' undeclared (first use in this function)",
1470 IDENTIFIER_POINTER (id));
1472 if (! undeclared_variable_notice)
1474 error ("(Each undeclared identifier is reported only once");
1475 error ("for each function it appears in.)");
1476 undeclared_variable_notice = 1;
1479 IDENTIFIER_GLOBAL_VALUE (id) = error_mark_node;
1480 IDENTIFIER_ERROR_LOCUS (id) = current_function_decl;
1482 return error_mark_node;
1487 /* Properly declared variable or function reference. */
1490 else if (decl != objc_ivar && IDENTIFIER_LOCAL_VALUE (id))
1492 warning ("local declaration of `%s' hides instance variable",
1493 IDENTIFIER_POINTER (id));
1500 if (TREE_TYPE (ref) == error_mark_node)
1501 return error_mark_node;
1503 assemble_external (ref);
1504 TREE_USED (ref) = 1;
1506 if (TREE_CODE (ref) == CONST_DECL)
1508 ref = DECL_INITIAL (ref);
1509 TREE_CONSTANT (ref) = 1;
1515 /* Build a function call to function FUNCTION with parameters PARAMS.
1516 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1517 TREE_VALUE of each node is a parameter-expression.
1518 FUNCTION's data type may be a function type or a pointer-to-function. */
1521 build_function_call (function, params)
1522 tree function, params;
1524 register tree fntype, fundecl = 0;
1525 register tree coerced_params;
1526 tree name = NULL_TREE, assembler_name = NULL_TREE, result;
1528 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1529 STRIP_TYPE_NOPS (function);
1531 /* Convert anything with function type to a pointer-to-function. */
1532 if (TREE_CODE (function) == FUNCTION_DECL)
1534 name = DECL_NAME (function);
1535 assembler_name = DECL_ASSEMBLER_NAME (function);
1537 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1538 (because calling an inline function does not mean the function
1539 needs to be separately compiled). */
1540 fntype = build_type_variant (TREE_TYPE (function),
1541 TREE_READONLY (function),
1542 TREE_THIS_VOLATILE (function));
1544 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
1547 function = default_conversion (function);
1549 fntype = TREE_TYPE (function);
1551 if (TREE_CODE (fntype) == ERROR_MARK)
1552 return error_mark_node;
1554 if (!(TREE_CODE (fntype) == POINTER_TYPE
1555 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
1557 error ("called object is not a function");
1558 return error_mark_node;
1561 /* fntype now gets the type of function pointed to. */
1562 fntype = TREE_TYPE (fntype);
1564 /* Convert the parameters to the types declared in the
1565 function prototype, or apply default promotions. */
1568 = convert_arguments (TYPE_ARG_TYPES (fntype), params, name, fundecl);
1570 /* Check for errors in format strings. */
1572 if (warn_format && (name || assembler_name))
1573 check_function_format (NULL, name, assembler_name, coerced_params);
1575 /* Recognize certain built-in functions so we can make tree-codes
1576 other than CALL_EXPR. We do this when it enables fold-const.c
1577 to do something useful. */
1579 if (TREE_CODE (function) == ADDR_EXPR
1580 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
1581 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
1583 result = expand_tree_builtin (TREE_OPERAND (function, 0),
1584 params, coerced_params);
1589 result = build (CALL_EXPR, TREE_TYPE (fntype),
1590 function, coerced_params, NULL_TREE);
1591 TREE_SIDE_EFFECTS (result) = 1;
1592 result = fold (result);
1594 if (VOID_TYPE_P (TREE_TYPE (result)))
1596 return require_complete_type (result);
1599 /* Convert the argument expressions in the list VALUES
1600 to the types in the list TYPELIST. The result is a list of converted
1601 argument expressions.
1603 If TYPELIST is exhausted, or when an element has NULL as its type,
1604 perform the default conversions.
1606 PARMLIST is the chain of parm decls for the function being called.
1607 It may be 0, if that info is not available.
1608 It is used only for generating error messages.
1610 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1612 This is also where warnings about wrong number of args are generated.
1614 Both VALUES and the returned value are chains of TREE_LIST nodes
1615 with the elements of the list in the TREE_VALUE slots of those nodes. */
1618 convert_arguments (typelist, values, name, fundecl)
1619 tree typelist, values, name, fundecl;
1621 register tree typetail, valtail;
1622 register tree result = NULL;
1625 /* Scan the given expressions and types, producing individual
1626 converted arguments and pushing them on RESULT in reverse order. */
1628 for (valtail = values, typetail = typelist, parmnum = 0;
1630 valtail = TREE_CHAIN (valtail), parmnum++)
1632 register tree type = typetail ? TREE_VALUE (typetail) : 0;
1633 register tree val = TREE_VALUE (valtail);
1635 if (type == void_type_node)
1638 error ("too many arguments to function `%s'",
1639 IDENTIFIER_POINTER (name));
1641 error ("too many arguments to function");
1645 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1646 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1647 to convert automatically to a pointer. */
1648 if (TREE_CODE (val) == NON_LVALUE_EXPR)
1649 val = TREE_OPERAND (val, 0);
1651 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
1652 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE)
1653 val = default_conversion (val);
1655 val = require_complete_type (val);
1659 /* Formal parm type is specified by a function prototype. */
1662 if (!COMPLETE_TYPE_P (type))
1664 error ("type of formal parameter %d is incomplete", parmnum + 1);
1669 /* Optionally warn about conversions that
1670 differ from the default conversions. */
1671 if (warn_conversion)
1673 int formal_prec = TYPE_PRECISION (type);
1675 if (INTEGRAL_TYPE_P (type)
1676 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1677 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1678 else if (TREE_CODE (type) == COMPLEX_TYPE
1679 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1680 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1681 else if (TREE_CODE (type) == REAL_TYPE
1682 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1683 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1684 else if (TREE_CODE (type) == REAL_TYPE
1685 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
1686 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1687 /* ??? At some point, messages should be written about
1688 conversions between complex types, but that's too messy
1690 else if (TREE_CODE (type) == REAL_TYPE
1691 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1693 /* Warn if any argument is passed as `float',
1694 since without a prototype it would be `double'. */
1695 if (formal_prec == TYPE_PRECISION (float_type_node))
1696 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1698 /* Detect integer changing in width or signedness. */
1699 else if (INTEGRAL_TYPE_P (type)
1700 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
1702 tree would_have_been = default_conversion (val);
1703 tree type1 = TREE_TYPE (would_have_been);
1705 if (TREE_CODE (type) == ENUMERAL_TYPE
1706 && type == TREE_TYPE (val))
1707 /* No warning if function asks for enum
1708 and the actual arg is that enum type. */
1710 else if (formal_prec != TYPE_PRECISION (type1))
1711 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1712 else if (TREE_UNSIGNED (type) == TREE_UNSIGNED (type1))
1714 /* Don't complain if the formal parameter type
1715 is an enum, because we can't tell now whether
1716 the value was an enum--even the same enum. */
1717 else if (TREE_CODE (type) == ENUMERAL_TYPE)
1719 else if (TREE_CODE (val) == INTEGER_CST
1720 && int_fits_type_p (val, type))
1721 /* Change in signedness doesn't matter
1722 if a constant value is unaffected. */
1724 /* Likewise for a constant in a NOP_EXPR. */
1725 else if (TREE_CODE (val) == NOP_EXPR
1726 && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST
1727 && int_fits_type_p (TREE_OPERAND (val, 0), type))
1729 #if 0 /* We never get such tree structure here. */
1730 else if (TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE
1731 && int_fits_type_p (TYPE_MIN_VALUE (TREE_TYPE (val)), type)
1732 && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE (val)), type))
1733 /* Change in signedness doesn't matter
1734 if an enum value is unaffected. */
1737 /* If the value is extended from a narrower
1738 unsigned type, it doesn't matter whether we
1739 pass it as signed or unsigned; the value
1740 certainly is the same either way. */
1741 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
1742 && TREE_UNSIGNED (TREE_TYPE (val)))
1744 else if (TREE_UNSIGNED (type))
1745 warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1);
1747 warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1);
1751 parmval = convert_for_assignment (type, val,
1752 (char *) 0, /* arg passing */
1753 fundecl, name, parmnum + 1);
1755 if (PROMOTE_PROTOTYPES
1756 && (TREE_CODE (type) == INTEGER_TYPE
1757 || TREE_CODE (type) == ENUMERAL_TYPE
1758 || TREE_CODE (type) == BOOLEAN_TYPE)
1759 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
1760 parmval = default_conversion (parmval);
1762 result = tree_cons (NULL_TREE, parmval, result);
1764 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
1765 && (TYPE_PRECISION (TREE_TYPE (val))
1766 < TYPE_PRECISION (double_type_node)))
1767 /* Convert `float' to `double'. */
1768 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
1770 /* Convert `short' and `char' to full-size `int'. */
1771 result = tree_cons (NULL_TREE, default_conversion (val), result);
1774 typetail = TREE_CHAIN (typetail);
1777 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
1780 error ("too few arguments to function `%s'",
1781 IDENTIFIER_POINTER (name));
1783 error ("too few arguments to function");
1786 return nreverse (result);
1789 /* This is the entry point used by the parser
1790 for binary operators in the input.
1791 In addition to constructing the expression,
1792 we check for operands that were written with other binary operators
1793 in a way that is likely to confuse the user. */
1796 parser_build_binary_op (code, arg1, arg2)
1797 enum tree_code code;
1800 tree result = build_binary_op (code, arg1, arg2, 1);
1803 char class1 = TREE_CODE_CLASS (TREE_CODE (arg1));
1804 char class2 = TREE_CODE_CLASS (TREE_CODE (arg2));
1805 enum tree_code code1 = ERROR_MARK;
1806 enum tree_code code2 = ERROR_MARK;
1808 if (class1 == 'e' || class1 == '1'
1809 || class1 == '2' || class1 == '<')
1810 code1 = C_EXP_ORIGINAL_CODE (arg1);
1811 if (class2 == 'e' || class2 == '1'
1812 || class2 == '2' || class2 == '<')
1813 code2 = C_EXP_ORIGINAL_CODE (arg2);
1815 /* Check for cases such as x+y<<z which users are likely
1816 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1817 is cleared to prevent these warnings. */
1818 if (warn_parentheses)
1820 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
1822 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1823 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1824 warning ("suggest parentheses around + or - inside shift");
1827 if (code == TRUTH_ORIF_EXPR)
1829 if (code1 == TRUTH_ANDIF_EXPR
1830 || code2 == TRUTH_ANDIF_EXPR)
1831 warning ("suggest parentheses around && within ||");
1834 if (code == BIT_IOR_EXPR)
1836 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
1837 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1838 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
1839 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1840 warning ("suggest parentheses around arithmetic in operand of |");
1841 /* Check cases like x|y==z */
1842 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1843 warning ("suggest parentheses around comparison in operand of |");
1846 if (code == BIT_XOR_EXPR)
1848 if (code1 == BIT_AND_EXPR
1849 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
1850 || code2 == BIT_AND_EXPR
1851 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1852 warning ("suggest parentheses around arithmetic in operand of ^");
1853 /* Check cases like x^y==z */
1854 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1855 warning ("suggest parentheses around comparison in operand of ^");
1858 if (code == BIT_AND_EXPR)
1860 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
1861 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
1862 warning ("suggest parentheses around + or - in operand of &");
1863 /* Check cases like x&y==z */
1864 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
1865 warning ("suggest parentheses around comparison in operand of &");
1869 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1870 if (TREE_CODE_CLASS (code) == '<' && extra_warnings
1871 && (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<'))
1872 warning ("comparisons like X<=Y<=Z do not have their mathematical meaning");
1874 unsigned_conversion_warning (result, arg1);
1875 unsigned_conversion_warning (result, arg2);
1876 overflow_warning (result);
1878 class = TREE_CODE_CLASS (TREE_CODE (result));
1880 /* Record the code that was specified in the source,
1881 for the sake of warnings about confusing nesting. */
1882 if (class == 'e' || class == '1'
1883 || class == '2' || class == '<')
1884 C_SET_EXP_ORIGINAL_CODE (result, code);
1887 int flag = TREE_CONSTANT (result);
1888 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1889 so that convert_for_assignment wouldn't strip it.
1890 That way, we got warnings for things like p = (1 - 1).
1891 But it turns out we should not get those warnings. */
1892 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
1893 C_SET_EXP_ORIGINAL_CODE (result, code);
1894 TREE_CONSTANT (result) = flag;
1900 /* Build a binary-operation expression without default conversions.
1901 CODE is the kind of expression to build.
1902 This function differs from `build' in several ways:
1903 the data type of the result is computed and recorded in it,
1904 warnings are generated if arg data types are invalid,
1905 special handling for addition and subtraction of pointers is known,
1906 and some optimization is done (operations on narrow ints
1907 are done in the narrower type when that gives the same result).
1908 Constant folding is also done before the result is returned.
1910 Note that the operands will never have enumeral types, or function
1911 or array types, because either they will have the default conversions
1912 performed or they have both just been converted to some other type in which
1913 the arithmetic is to be done. */
1916 build_binary_op (code, orig_op0, orig_op1, convert_p)
1917 enum tree_code code;
1918 tree orig_op0, orig_op1;
1922 register enum tree_code code0, code1;
1925 /* Expression code to give to the expression when it is built.
1926 Normally this is CODE, which is what the caller asked for,
1927 but in some special cases we change it. */
1928 register enum tree_code resultcode = code;
1930 /* Data type in which the computation is to be performed.
1931 In the simplest cases this is the common type of the arguments. */
1932 register tree result_type = NULL;
1934 /* Nonzero means operands have already been type-converted
1935 in whatever way is necessary.
1936 Zero means they need to be converted to RESULT_TYPE. */
1939 /* Nonzero means create the expression with this type, rather than
1941 tree build_type = 0;
1943 /* Nonzero means after finally constructing the expression
1944 convert it to this type. */
1945 tree final_type = 0;
1947 /* Nonzero if this is an operation like MIN or MAX which can
1948 safely be computed in short if both args are promoted shorts.
1949 Also implies COMMON.
1950 -1 indicates a bitwise operation; this makes a difference
1951 in the exact conditions for when it is safe to do the operation
1952 in a narrower mode. */
1955 /* Nonzero if this is a comparison operation;
1956 if both args are promoted shorts, compare the original shorts.
1957 Also implies COMMON. */
1958 int short_compare = 0;
1960 /* Nonzero if this is a right-shift operation, which can be computed on the
1961 original short and then promoted if the operand is a promoted short. */
1962 int short_shift = 0;
1964 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1969 op0 = default_conversion (orig_op0);
1970 op1 = default_conversion (orig_op1);
1978 type0 = TREE_TYPE (op0);
1979 type1 = TREE_TYPE (op1);
1981 /* The expression codes of the data types of the arguments tell us
1982 whether the arguments are integers, floating, pointers, etc. */
1983 code0 = TREE_CODE (type0);
1984 code1 = TREE_CODE (type1);
1986 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1987 STRIP_TYPE_NOPS (op0);
1988 STRIP_TYPE_NOPS (op1);
1990 /* If an error was already reported for one of the arguments,
1991 avoid reporting another error. */
1993 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
1994 return error_mark_node;
1999 /* Handle the pointer + int case. */
2000 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2001 return pointer_int_sum (PLUS_EXPR, op0, op1);
2002 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
2003 return pointer_int_sum (PLUS_EXPR, op1, op0);
2009 /* Subtraction of two similar pointers.
2010 We must subtract them as integers, then divide by object size. */
2011 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
2012 && comp_target_types (type0, type1))
2013 return pointer_diff (op0, op1);
2014 /* Handle pointer minus int. Just like pointer plus int. */
2015 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2016 return pointer_int_sum (MINUS_EXPR, op0, op1);
2025 case TRUNC_DIV_EXPR:
2027 case FLOOR_DIV_EXPR:
2028 case ROUND_DIV_EXPR:
2029 case EXACT_DIV_EXPR:
2030 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2031 || code0 == COMPLEX_TYPE)
2032 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2033 || code1 == COMPLEX_TYPE))
2035 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
2036 resultcode = RDIV_EXPR;
2038 /* Although it would be tempting to shorten always here, that
2039 loses on some targets, since the modulo instruction is
2040 undefined if the quotient can't be represented in the
2041 computation mode. We shorten only if unsigned or if
2042 dividing by something we know != -1. */
2043 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
2044 || (TREE_CODE (op1) == INTEGER_CST
2045 && ! integer_all_onesp (op1)));
2051 case BIT_ANDTC_EXPR:
2054 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2056 /* If one operand is a constant, and the other is a short type
2057 that has been converted to an int,
2058 really do the work in the short type and then convert the
2059 result to int. If we are lucky, the constant will be 0 or 1
2060 in the short type, making the entire operation go away. */
2061 if (TREE_CODE (op0) == INTEGER_CST
2062 && TREE_CODE (op1) == NOP_EXPR
2063 && TYPE_PRECISION (type1) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))
2064 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0))))
2066 final_type = result_type;
2067 op1 = TREE_OPERAND (op1, 0);
2068 result_type = TREE_TYPE (op1);
2070 if (TREE_CODE (op1) == INTEGER_CST
2071 && TREE_CODE (op0) == NOP_EXPR
2072 && TYPE_PRECISION (type0) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))
2073 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2075 final_type = result_type;
2076 op0 = TREE_OPERAND (op0, 0);
2077 result_type = TREE_TYPE (op0);
2081 case TRUNC_MOD_EXPR:
2082 case FLOOR_MOD_EXPR:
2083 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2085 /* Although it would be tempting to shorten always here, that loses
2086 on some targets, since the modulo instruction is undefined if the
2087 quotient can't be represented in the computation mode. We shorten
2088 only if unsigned or if dividing by something we know != -1. */
2089 shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0))
2090 || (TREE_CODE (op1) == INTEGER_CST
2091 && ! integer_all_onesp (op1)));
2096 case TRUTH_ANDIF_EXPR:
2097 case TRUTH_ORIF_EXPR:
2098 case TRUTH_AND_EXPR:
2100 case TRUTH_XOR_EXPR:
2101 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
2102 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2103 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
2104 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2106 /* Result of these operations is always an int,
2107 but that does not mean the operands should be
2108 converted to ints! */
2109 result_type = integer_type_node;
2110 op0 = truthvalue_conversion (op0);
2111 op1 = truthvalue_conversion (op1);
2116 /* Shift operations: result has same type as first operand;
2117 always convert second operand to int.
2118 Also set SHORT_SHIFT if shifting rightward. */
2121 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2123 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2125 if (tree_int_cst_sgn (op1) < 0)
2126 warning ("right shift count is negative");
2129 if (! integer_zerop (op1))
2132 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2133 warning ("right shift count >= width of type");
2137 /* Use the type of the value to be shifted.
2138 This is what most traditional C compilers do. */
2139 result_type = type0;
2140 /* Unless traditional, convert the shift-count to an integer,
2141 regardless of size of value being shifted. */
2142 if (! flag_traditional)
2144 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2145 op1 = convert (integer_type_node, op1);
2146 /* Avoid converting op1 to result_type later. */
2153 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2155 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2157 if (tree_int_cst_sgn (op1) < 0)
2158 warning ("left shift count is negative");
2160 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2161 warning ("left shift count >= width of type");
2164 /* Use the type of the value to be shifted.
2165 This is what most traditional C compilers do. */
2166 result_type = type0;
2167 /* Unless traditional, convert the shift-count to an integer,
2168 regardless of size of value being shifted. */
2169 if (! flag_traditional)
2171 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2172 op1 = convert (integer_type_node, op1);
2173 /* Avoid converting op1 to result_type later. */
2181 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2183 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
2185 if (tree_int_cst_sgn (op1) < 0)
2186 warning ("shift count is negative");
2187 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2188 warning ("shift count >= width of type");
2191 /* Use the type of the value to be shifted.
2192 This is what most traditional C compilers do. */
2193 result_type = type0;
2194 /* Unless traditional, convert the shift-count to an integer,
2195 regardless of size of value being shifted. */
2196 if (! flag_traditional)
2198 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2199 op1 = convert (integer_type_node, op1);
2200 /* Avoid converting op1 to result_type later. */
2208 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
2209 warning ("comparing floating point with == or != is unsafe");
2210 /* Result of comparison is always int,
2211 but don't convert the args to int! */
2212 build_type = integer_type_node;
2213 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2214 || code0 == COMPLEX_TYPE)
2215 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2216 || code1 == COMPLEX_TYPE))
2218 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2220 register tree tt0 = TREE_TYPE (type0);
2221 register tree tt1 = TREE_TYPE (type1);
2222 /* Anything compares with void *. void * compares with anything.
2223 Otherwise, the targets must be compatible
2224 and both must be object or both incomplete. */
2225 if (comp_target_types (type0, type1))
2226 result_type = common_type (type0, type1);
2227 else if (VOID_TYPE_P (tt0))
2229 /* op0 != orig_op0 detects the case of something
2230 whose value is 0 but which isn't a valid null ptr const. */
2231 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
2232 && TREE_CODE (tt1) == FUNCTION_TYPE)
2233 pedwarn ("ISO C forbids comparison of `void *' with function pointer");
2235 else if (VOID_TYPE_P (tt1))
2237 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
2238 && TREE_CODE (tt0) == FUNCTION_TYPE)
2239 pedwarn ("ISO C forbids comparison of `void *' with function pointer");
2242 pedwarn ("comparison of distinct pointer types lacks a cast");
2244 if (result_type == NULL_TREE)
2245 result_type = ptr_type_node;
2247 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2248 && integer_zerop (op1))
2249 result_type = type0;
2250 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2251 && integer_zerop (op0))
2252 result_type = type1;
2253 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2255 result_type = type0;
2256 if (! flag_traditional)
2257 pedwarn ("comparison between pointer and integer");
2259 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2261 result_type = type1;
2262 if (! flag_traditional)
2263 pedwarn ("comparison between pointer and integer");
2269 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2270 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2272 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2274 if (comp_target_types (type0, type1))
2276 result_type = common_type (type0, type1);
2278 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2279 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
2283 result_type = ptr_type_node;
2284 pedwarn ("comparison of distinct pointer types lacks a cast");
2293 build_type = integer_type_node;
2294 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
2295 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
2297 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2299 if (comp_target_types (type0, type1))
2301 result_type = common_type (type0, type1);
2302 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
2303 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
2304 pedwarn ("comparison of complete and incomplete pointers");
2306 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
2307 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
2311 result_type = ptr_type_node;
2312 pedwarn ("comparison of distinct pointer types lacks a cast");
2315 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
2316 && integer_zerop (op1))
2318 result_type = type0;
2319 if (pedantic || extra_warnings)
2320 pedwarn ("ordered comparison of pointer with integer zero");
2322 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
2323 && integer_zerop (op0))
2325 result_type = type1;
2327 pedwarn ("ordered comparison of pointer with integer zero");
2329 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2331 result_type = type0;
2332 if (! flag_traditional)
2333 pedwarn ("comparison between pointer and integer");
2335 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2337 result_type = type1;
2338 if (! flag_traditional)
2339 pedwarn ("comparison between pointer and integer");
2343 case UNORDERED_EXPR:
2350 build_type = integer_type_node;
2351 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
2353 error ("unordered comparison on non-floating point argument");
2354 return error_mark_node;
2363 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
2365 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
2367 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
2369 if (shorten || common || short_compare)
2370 result_type = common_type (type0, type1);
2372 /* For certain operations (which identify themselves by shorten != 0)
2373 if both args were extended from the same smaller type,
2374 do the arithmetic in that type and then extend.
2376 shorten !=0 and !=1 indicates a bitwise operation.
2377 For them, this optimization is safe only if
2378 both args are zero-extended or both are sign-extended.
2379 Otherwise, we might change the result.
2380 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2381 but calculated in (unsigned short) it would be (unsigned short)-1. */
2383 if (shorten && none_complex)
2385 int unsigned0, unsigned1;
2386 tree arg0 = get_narrower (op0, &unsigned0);
2387 tree arg1 = get_narrower (op1, &unsigned1);
2388 /* UNS is 1 if the operation to be done is an unsigned one. */
2389 int uns = TREE_UNSIGNED (result_type);
2392 final_type = result_type;
2394 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2395 but it *requires* conversion to FINAL_TYPE. */
2397 if ((TYPE_PRECISION (TREE_TYPE (op0))
2398 == TYPE_PRECISION (TREE_TYPE (arg0)))
2399 && TREE_TYPE (op0) != final_type)
2400 unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
2401 if ((TYPE_PRECISION (TREE_TYPE (op1))
2402 == TYPE_PRECISION (TREE_TYPE (arg1)))
2403 && TREE_TYPE (op1) != final_type)
2404 unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
2406 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2408 /* For bitwise operations, signedness of nominal type
2409 does not matter. Consider only how operands were extended. */
2413 /* Note that in all three cases below we refrain from optimizing
2414 an unsigned operation on sign-extended args.
2415 That would not be valid. */
2417 /* Both args variable: if both extended in same way
2418 from same width, do it in that width.
2419 Do it unsigned if args were zero-extended. */
2420 if ((TYPE_PRECISION (TREE_TYPE (arg0))
2421 < TYPE_PRECISION (result_type))
2422 && (TYPE_PRECISION (TREE_TYPE (arg1))
2423 == TYPE_PRECISION (TREE_TYPE (arg0)))
2424 && unsigned0 == unsigned1
2425 && (unsigned0 || !uns))
2427 = signed_or_unsigned_type (unsigned0,
2428 common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
2429 else if (TREE_CODE (arg0) == INTEGER_CST
2430 && (unsigned1 || !uns)
2431 && (TYPE_PRECISION (TREE_TYPE (arg1))
2432 < TYPE_PRECISION (result_type))
2433 && (type = signed_or_unsigned_type (unsigned1,
2435 int_fits_type_p (arg0, type)))
2437 else if (TREE_CODE (arg1) == INTEGER_CST
2438 && (unsigned0 || !uns)
2439 && (TYPE_PRECISION (TREE_TYPE (arg0))
2440 < TYPE_PRECISION (result_type))
2441 && (type = signed_or_unsigned_type (unsigned0,
2443 int_fits_type_p (arg1, type)))
2447 /* Shifts can be shortened if shifting right. */
2452 tree arg0 = get_narrower (op0, &unsigned_arg);
2454 final_type = result_type;
2456 if (arg0 == op0 && final_type == TREE_TYPE (op0))
2457 unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
2459 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
2460 /* We can shorten only if the shift count is less than the
2461 number of bits in the smaller type size. */
2462 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
2463 /* If arg is sign-extended and then unsigned-shifted,
2464 we can simulate this with a signed shift in arg's type
2465 only if the extended result is at least twice as wide
2466 as the arg. Otherwise, the shift could use up all the
2467 ones made by sign-extension and bring in zeros.
2468 We can't optimize that case at all, but in most machines
2469 it never happens because available widths are 2**N. */
2470 && (!TREE_UNSIGNED (final_type)
2472 || (2 * TYPE_PRECISION (TREE_TYPE (arg0))
2473 <= TYPE_PRECISION (result_type))))
2475 /* Do an unsigned shift if the operand was zero-extended. */
2477 = signed_or_unsigned_type (unsigned_arg,
2479 /* Convert value-to-be-shifted to that type. */
2480 if (TREE_TYPE (op0) != result_type)
2481 op0 = convert (result_type, op0);
2486 /* Comparison operations are shortened too but differently.
2487 They identify themselves by setting short_compare = 1. */
2491 /* Don't write &op0, etc., because that would prevent op0
2492 from being kept in a register.
2493 Instead, make copies of the our local variables and
2494 pass the copies by reference, then copy them back afterward. */
2495 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
2496 enum tree_code xresultcode = resultcode;
2498 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
2503 op0 = xop0, op1 = xop1;
2505 resultcode = xresultcode;
2507 if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare != 0)
2508 && skip_evaluation == 0)
2510 int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0));
2511 int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1));
2512 int unsignedp0, unsignedp1;
2513 tree primop0 = get_narrower (op0, &unsignedp0);
2514 tree primop1 = get_narrower (op1, &unsignedp1);
2518 STRIP_TYPE_NOPS (xop0);
2519 STRIP_TYPE_NOPS (xop1);
2521 /* Give warnings for comparisons between signed and unsigned
2522 quantities that may fail.
2524 Do the checking based on the original operand trees, so that
2525 casts will be considered, but default promotions won't be.
2527 Do not warn if the comparison is being done in a signed type,
2528 since the signed type will only be chosen if it can represent
2529 all the values of the unsigned type. */
2530 if (! TREE_UNSIGNED (result_type))
2532 /* Do not warn if both operands are the same signedness. */
2533 else if (op0_signed == op1_signed)
2540 sop = xop0, uop = xop1;
2542 sop = xop1, uop = xop0;
2544 /* Do not warn if the signed quantity is an
2545 unsuffixed integer literal (or some static
2546 constant expression involving such literals or a
2547 conditional expression involving such literals)
2548 and it is non-negative. */
2549 if (tree_expr_nonnegative_p (sop))
2551 /* Do not warn if the comparison is an equality operation,
2552 the unsigned quantity is an integral constant, and it
2553 would fit in the result if the result were signed. */
2554 else if (TREE_CODE (uop) == INTEGER_CST
2555 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
2556 && int_fits_type_p (uop, signed_type (result_type)))
2558 /* Do not warn if the unsigned quantity is an enumeration
2559 constant and its maximum value would fit in the result
2560 if the result were signed. */
2561 else if (TREE_CODE (uop) == INTEGER_CST
2562 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
2563 && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE(uop)),
2564 signed_type (result_type)))
2567 warning ("comparison between signed and unsigned");
2570 /* Warn if two unsigned values are being compared in a size
2571 larger than their original size, and one (and only one) is the
2572 result of a `~' operator. This comparison will always fail.
2574 Also warn if one operand is a constant, and the constant
2575 does not have all bits set that are set in the ~ operand
2576 when it is extended. */
2578 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
2579 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
2581 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
2582 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
2585 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
2588 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
2591 HOST_WIDE_INT constant, mask;
2592 int unsignedp, bits;
2594 if (host_integerp (primop0, 0))
2597 unsignedp = unsignedp1;
2598 constant = tree_low_cst (primop0, 0);
2603 unsignedp = unsignedp0;
2604 constant = tree_low_cst (primop1, 0);
2607 bits = TYPE_PRECISION (TREE_TYPE (primop));
2608 if (bits < TYPE_PRECISION (result_type)
2609 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
2611 mask = (~ (HOST_WIDE_INT) 0) << bits;
2612 if ((mask & constant) != mask)
2613 warning ("comparison of promoted ~unsigned with constant");
2616 else if (unsignedp0 && unsignedp1
2617 && (TYPE_PRECISION (TREE_TYPE (primop0))
2618 < TYPE_PRECISION (result_type))
2619 && (TYPE_PRECISION (TREE_TYPE (primop1))
2620 < TYPE_PRECISION (result_type)))
2621 warning ("comparison of promoted ~unsigned with unsigned");
2627 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2628 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2629 Then the expression will be built.
2630 It will be given type FINAL_TYPE if that is nonzero;
2631 otherwise, it will be given type RESULT_TYPE. */
2635 binary_op_error (code);
2636 return error_mark_node;
2641 if (TREE_TYPE (op0) != result_type)
2642 op0 = convert (result_type, op0);
2643 if (TREE_TYPE (op1) != result_type)
2644 op1 = convert (result_type, op1);
2647 if (build_type == NULL_TREE)
2648 build_type = result_type;
2651 register tree result = build (resultcode, build_type, op0, op1);
2652 register tree folded;
2654 folded = fold (result);
2655 if (folded == result)
2656 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2657 if (final_type != 0)
2658 return convert (final_type, folded);
2663 /* Return a tree for the sum or difference (RESULTCODE says which)
2664 of pointer PTROP and integer INTOP. */
2667 pointer_int_sum (resultcode, ptrop, intop)
2668 enum tree_code resultcode;
2669 register tree ptrop, intop;
2673 register tree result;
2674 register tree folded;
2676 /* The result is a pointer of the same type that is being added. */
2678 register tree result_type = TREE_TYPE (ptrop);
2680 if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
2682 if (pedantic || warn_pointer_arith)
2683 pedwarn ("pointer of type `void *' used in arithmetic");
2684 size_exp = integer_one_node;
2686 else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
2688 if (pedantic || warn_pointer_arith)
2689 pedwarn ("pointer to a function used in arithmetic");
2690 size_exp = integer_one_node;
2693 size_exp = c_size_in_bytes (TREE_TYPE (result_type));
2695 /* If what we are about to multiply by the size of the elements
2696 contains a constant term, apply distributive law
2697 and multiply that constant term separately.
2698 This helps produce common subexpressions. */
2700 if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
2701 && ! TREE_CONSTANT (intop)
2702 && TREE_CONSTANT (TREE_OPERAND (intop, 1))
2703 && TREE_CONSTANT (size_exp)
2704 /* If the constant comes from pointer subtraction,
2705 skip this optimization--it would cause an error. */
2706 && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE
2707 /* If the constant is unsigned, and smaller than the pointer size,
2708 then we must skip this optimization. This is because it could cause
2709 an overflow error if the constant is negative but INTOP is not. */
2710 && (! TREE_UNSIGNED (TREE_TYPE (intop))
2711 || (TYPE_PRECISION (TREE_TYPE (intop))
2712 == TYPE_PRECISION (TREE_TYPE (ptrop)))))
2714 enum tree_code subcode = resultcode;
2715 tree int_type = TREE_TYPE (intop);
2716 if (TREE_CODE (intop) == MINUS_EXPR)
2717 subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
2718 /* Convert both subexpression types to the type of intop,
2719 because weird cases involving pointer arithmetic
2720 can result in a sum or difference with different type args. */
2721 ptrop = build_binary_op (subcode, ptrop,
2722 convert (int_type, TREE_OPERAND (intop, 1)), 1);
2723 intop = convert (int_type, TREE_OPERAND (intop, 0));
2726 /* Convert the integer argument to a type the same size as sizetype
2727 so the multiply won't overflow spuriously. */
2729 if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype)
2730 || TREE_UNSIGNED (TREE_TYPE (intop)) != TREE_UNSIGNED (sizetype))
2731 intop = convert (type_for_size (TYPE_PRECISION (sizetype),
2732 TREE_UNSIGNED (sizetype)), intop);
2734 /* Replace the integer argument with a suitable product by the object size.
2735 Do this multiplication as signed, then convert to the appropriate
2736 pointer type (actually unsigned integral). */
2738 intop = convert (result_type,
2739 build_binary_op (MULT_EXPR, intop,
2740 convert (TREE_TYPE (intop), size_exp), 1));
2742 /* Create the sum or difference. */
2744 result = build (resultcode, result_type, ptrop, intop);
2746 folded = fold (result);
2747 if (folded == result)
2748 TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop);
2752 /* Return a tree for the difference of pointers OP0 and OP1.
2753 The resulting tree has type int. */
2756 pointer_diff (op0, op1)
2757 register tree op0, op1;
2759 register tree result, folded;
2760 tree restype = ptrdiff_type_node;
2762 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2764 if (pedantic || warn_pointer_arith)
2766 if (TREE_CODE (target_type) == VOID_TYPE)
2767 pedwarn ("pointer of type `void *' used in subtraction");
2768 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2769 pedwarn ("pointer to a function used in subtraction");
2772 /* First do the subtraction as integers;
2773 then drop through to build the divide operator.
2774 Do not do default conversions on the minus operator
2775 in case restype is a short type. */
2777 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2778 convert (restype, op1), 0);
2779 /* This generates an error if op1 is pointer to incomplete type. */
2780 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
2781 error ("arithmetic on pointer to an incomplete type");
2783 /* This generates an error if op0 is pointer to incomplete type. */
2784 op1 = c_size_in_bytes (target_type);
2786 /* Divide by the size, in easiest possible way. */
2788 result = build (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2790 folded = fold (result);
2791 if (folded == result)
2792 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
2796 /* Construct and perhaps optimize a tree representation
2797 for a unary operation. CODE, a tree_code, specifies the operation
2798 and XARG is the operand. NOCONVERT nonzero suppresses
2799 the default promotions (such as from short to int). */
2802 build_unary_op (code, xarg, noconvert)
2803 enum tree_code code;
2807 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2808 register tree arg = xarg;
2809 register tree argtype = 0;
2810 register enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2813 if (typecode == ERROR_MARK)
2814 return error_mark_node;
2815 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2816 typecode = INTEGER_TYPE;
2821 /* This is used for unary plus, because a CONVERT_EXPR
2822 is enough to prevent anybody from looking inside for
2823 associativity, but won't generate any code. */
2824 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2825 || typecode == COMPLEX_TYPE))
2827 error ("wrong type argument to unary plus");
2828 return error_mark_node;
2830 else if (!noconvert)
2831 arg = default_conversion (arg);
2835 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2836 || typecode == COMPLEX_TYPE))
2838 error ("wrong type argument to unary minus");
2839 return error_mark_node;
2841 else if (!noconvert)
2842 arg = default_conversion (arg);
2846 if (typecode == COMPLEX_TYPE)
2850 pedwarn ("ISO C does not support `~' for complex conjugation");
2852 arg = default_conversion (arg);
2854 else if (typecode != INTEGER_TYPE)
2856 error ("wrong type argument to bit-complement");
2857 return error_mark_node;
2859 else if (!noconvert)
2860 arg = default_conversion (arg);
2864 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2865 || typecode == COMPLEX_TYPE))
2867 error ("wrong type argument to abs");
2868 return error_mark_node;
2870 else if (!noconvert)
2871 arg = default_conversion (arg);
2875 /* Conjugating a real value is a no-op, but allow it anyway. */
2876 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2877 || typecode == COMPLEX_TYPE))
2879 error ("wrong type argument to conjugation");
2880 return error_mark_node;
2882 else if (!noconvert)
2883 arg = default_conversion (arg);
2886 case TRUTH_NOT_EXPR:
2887 if (typecode != INTEGER_TYPE
2888 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2889 && typecode != COMPLEX_TYPE
2890 /* These will convert to a pointer. */
2891 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2893 error ("wrong type argument to unary exclamation mark");
2894 return error_mark_node;
2896 arg = truthvalue_conversion (arg);
2897 return invert_truthvalue (arg);
2903 if (TREE_CODE (arg) == COMPLEX_CST)
2904 return TREE_REALPART (arg);
2905 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2906 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2911 if (TREE_CODE (arg) == COMPLEX_CST)
2912 return TREE_IMAGPART (arg);
2913 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2914 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2916 return convert (TREE_TYPE (arg), integer_zero_node);
2918 case PREINCREMENT_EXPR:
2919 case POSTINCREMENT_EXPR:
2920 case PREDECREMENT_EXPR:
2921 case POSTDECREMENT_EXPR:
2922 /* Handle complex lvalues (when permitted)
2923 by reduction to simpler cases. */
2925 val = unary_complex_lvalue (code, arg);
2929 /* Increment or decrement the real part of the value,
2930 and don't change the imaginary part. */
2931 if (typecode == COMPLEX_TYPE)
2936 pedwarn ("ISO C does not support `++' and `--' on complex types");
2938 arg = stabilize_reference (arg);
2939 real = build_unary_op (REALPART_EXPR, arg, 1);
2940 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2941 return build (COMPLEX_EXPR, TREE_TYPE (arg),
2942 build_unary_op (code, real, 1), imag);
2945 /* Report invalid types. */
2947 if (typecode != POINTER_TYPE
2948 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2950 error ("wrong type argument to %s",
2951 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2952 ? "increment" : "decrement");
2953 return error_mark_node;
2958 tree result_type = TREE_TYPE (arg);
2960 arg = get_unwidened (arg, 0);
2961 argtype = TREE_TYPE (arg);
2963 /* Compute the increment. */
2965 if (typecode == POINTER_TYPE)
2967 /* If pointer target is an undefined struct,
2968 we just cannot know how to do the arithmetic. */
2969 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2970 error ("%s of pointer to unknown structure",
2971 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2972 ? "increment" : "decrement");
2973 else if ((pedantic || warn_pointer_arith)
2974 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2975 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2976 pedwarn ("wrong type argument to %s",
2977 code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR
2978 ? "increment" : "decrement");
2979 inc = c_size_in_bytes (TREE_TYPE (result_type));
2982 inc = integer_one_node;
2984 inc = convert (argtype, inc);
2986 /* Handle incrementing a cast-expression. */
2989 switch (TREE_CODE (arg))
2994 case FIX_TRUNC_EXPR:
2995 case FIX_FLOOR_EXPR:
2996 case FIX_ROUND_EXPR:
2998 pedantic_lvalue_warning (CONVERT_EXPR);
2999 /* If the real type has the same machine representation
3000 as the type it is cast to, we can make better output
3001 by adding directly to the inside of the cast. */
3002 if ((TREE_CODE (TREE_TYPE (arg))
3003 == TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0))))
3004 && (TYPE_MODE (TREE_TYPE (arg))
3005 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (arg, 0)))))
3006 arg = TREE_OPERAND (arg, 0);
3009 tree incremented, modify, value;
3010 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3011 value = boolean_increment (code, arg);
3014 arg = stabilize_reference (arg);
3015 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
3018 value = save_expr (arg);
3019 incremented = build (((code == PREINCREMENT_EXPR
3020 || code == POSTINCREMENT_EXPR)
3021 ? PLUS_EXPR : MINUS_EXPR),
3022 argtype, value, inc);
3023 TREE_SIDE_EFFECTS (incremented) = 1;
3024 modify = build_modify_expr (arg, NOP_EXPR, incremented);
3025 value = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
3027 TREE_USED (value) = 1;
3037 /* Complain about anything else that is not a true lvalue. */
3038 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
3039 || code == POSTINCREMENT_EXPR)
3040 ? "invalid lvalue in increment"
3041 : "invalid lvalue in decrement")))
3042 return error_mark_node;
3044 /* Report a read-only lvalue. */
3045 if (TREE_READONLY (arg))
3046 readonly_warning (arg,
3047 ((code == PREINCREMENT_EXPR
3048 || code == POSTINCREMENT_EXPR)
3049 ? "increment" : "decrement"));
3051 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3052 val = boolean_increment (code, arg);
3054 val = build (code, TREE_TYPE (arg), arg, inc);
3055 TREE_SIDE_EFFECTS (val) = 1;
3056 val = convert (result_type, val);
3057 if (TREE_CODE (val) != code)
3058 TREE_NO_UNUSED_WARNING (val) = 1;
3063 /* Note that this operation never does default_conversion
3064 regardless of NOCONVERT. */
3066 /* Let &* cancel out to simplify resulting code. */
3067 if (TREE_CODE (arg) == INDIRECT_REF)
3069 /* Don't let this be an lvalue. */
3070 if (lvalue_p (TREE_OPERAND (arg, 0)))
3071 return non_lvalue (TREE_OPERAND (arg, 0));
3072 return TREE_OPERAND (arg, 0);
3075 /* For &x[y], return x+y */
3076 if (TREE_CODE (arg) == ARRAY_REF)
3078 if (mark_addressable (TREE_OPERAND (arg, 0)) == 0)
3079 return error_mark_node;
3080 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
3081 TREE_OPERAND (arg, 1), 1);
3084 /* Handle complex lvalues (when permitted)
3085 by reduction to simpler cases. */
3086 val = unary_complex_lvalue (code, arg);
3090 #if 0 /* Turned off because inconsistent;
3091 float f; *&(int)f = 3.4 stores in int format
3092 whereas (int)f = 3.4 stores in float format. */
3093 /* Address of a cast is just a cast of the address
3094 of the operand of the cast. */
3095 switch (TREE_CODE (arg))
3100 case FIX_TRUNC_EXPR:
3101 case FIX_FLOOR_EXPR:
3102 case FIX_ROUND_EXPR:
3105 pedwarn ("ISO C forbids the address of a cast expression");
3106 return convert (build_pointer_type (TREE_TYPE (arg)),
3107 build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0),
3112 /* Allow the address of a constructor if all the elements
3114 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_CONSTANT (arg))
3116 /* Anything not already handled and not a true memory reference
3118 else if (typecode != FUNCTION_TYPE
3119 && !lvalue_or_else (arg, "invalid lvalue in unary `&'"))
3120 return error_mark_node;
3122 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3123 argtype = TREE_TYPE (arg);
3125 /* If the lvalue is const or volatile, merge that into the type
3126 to which the address will point. Note that you can't get a
3127 restricted pointer by taking the address of something, so we
3128 only have to deal with `const' and `volatile' here. */
3129 if ((DECL_P (arg) || TREE_CODE_CLASS (TREE_CODE (arg)) == 'r')
3130 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
3131 argtype = c_build_type_variant (argtype,
3132 TREE_READONLY (arg),
3133 TREE_THIS_VOLATILE (arg));
3135 argtype = build_pointer_type (argtype);
3137 if (mark_addressable (arg) == 0)
3138 return error_mark_node;
3143 if (TREE_CODE (arg) == COMPONENT_REF)
3145 tree field = TREE_OPERAND (arg, 1);
3147 addr = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
3149 if (DECL_C_BIT_FIELD (field))
3151 error ("attempt to take address of bit-field structure member `%s'",
3152 IDENTIFIER_POINTER (DECL_NAME (field)));
3153 return error_mark_node;
3156 addr = fold (build (PLUS_EXPR, argtype,
3157 convert (argtype, addr),
3158 convert (argtype, byte_position (field))));
3161 addr = build1 (code, argtype, arg);
3163 /* Address of a static or external variable or
3164 file-scope function counts as a constant. */
3166 && ! (TREE_CODE (arg) == FUNCTION_DECL
3167 && DECL_CONTEXT (arg) != 0))
3168 TREE_CONSTANT (addr) = 1;
3177 argtype = TREE_TYPE (arg);
3178 return fold (build1 (code, argtype, arg));
3182 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3183 convert ARG with the same conversions in the same order
3184 and return the result. */
3187 convert_sequence (conversions, arg)
3191 switch (TREE_CODE (conversions))
3196 case FIX_TRUNC_EXPR:
3197 case FIX_FLOOR_EXPR:
3198 case FIX_ROUND_EXPR:
3200 return convert (TREE_TYPE (conversions),
3201 convert_sequence (TREE_OPERAND (conversions, 0),
3210 /* Return nonzero if REF is an lvalue valid for this language.
3211 Lvalues can be assigned, unless their type has TYPE_READONLY.
3212 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3218 register enum tree_code code = TREE_CODE (ref);
3225 return lvalue_p (TREE_OPERAND (ref, 0));
3236 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3237 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3241 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3248 /* Return nonzero if REF is an lvalue valid for this language;
3249 otherwise, print an error message and return zero. */
3252 lvalue_or_else (ref, msgid)
3256 int win = lvalue_p (ref);
3259 error ("%s", msgid);
3264 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3265 for certain kinds of expressions which are not really lvalues
3266 but which we can accept as lvalues.
3268 If ARG is not a kind of expression we can handle, return zero. */
3271 unary_complex_lvalue (code, arg)
3272 enum tree_code code;
3275 /* Handle (a, b) used as an "lvalue". */
3276 if (TREE_CODE (arg) == COMPOUND_EXPR)
3278 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
3280 /* If this returns a function type, it isn't really being used as
3281 an lvalue, so don't issue a warning about it. */
3282 if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE)
3283 pedantic_lvalue_warning (COMPOUND_EXPR);
3285 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
3286 TREE_OPERAND (arg, 0), real_result);
3289 /* Handle (a ? b : c) used as an "lvalue". */
3290 if (TREE_CODE (arg) == COND_EXPR)
3292 pedantic_lvalue_warning (COND_EXPR);
3293 if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE)
3294 pedantic_lvalue_warning (COMPOUND_EXPR);
3296 return (build_conditional_expr
3297 (TREE_OPERAND (arg, 0),
3298 build_unary_op (code, TREE_OPERAND (arg, 1), 0),
3299 build_unary_op (code, TREE_OPERAND (arg, 2), 0)));
3305 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3306 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3309 pedantic_lvalue_warning (code)
3310 enum tree_code code;
3316 pedwarn ("ISO C forbids use of conditional expressions as lvalues");
3319 pedwarn ("ISO C forbids use of compound expressions as lvalues");
3322 pedwarn ("ISO C forbids use of cast expressions as lvalues");
3327 /* Warn about storing in something that is `const'. */
3330 readonly_warning (arg, msgid)
3334 if (TREE_CODE (arg) == COMPONENT_REF)
3336 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3337 readonly_warning (TREE_OPERAND (arg, 0), msgid);
3339 pedwarn ("%s of read-only member `%s'", _(msgid),
3340 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1))));
3342 else if (TREE_CODE (arg) == VAR_DECL)
3343 pedwarn ("%s of read-only variable `%s'", _(msgid),
3344 IDENTIFIER_POINTER (DECL_NAME (arg)));
3346 pedwarn ("%s of read-only location", _(msgid));
3349 /* Mark EXP saying that we need to be able to take the
3350 address of it; it should not be allocated in a register.
3351 Value is 1 if successful. */
3354 mark_addressable (exp)
3357 register tree x = exp;
3359 switch (TREE_CODE (x))
3362 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3364 error ("cannot take address of bitfield `%s'",
3365 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (x, 1))));
3369 /* ... fall through ... */
3375 x = TREE_OPERAND (x, 0);
3379 TREE_ADDRESSABLE (x) = 1;
3386 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
3387 && DECL_NONLOCAL (x))
3389 if (TREE_PUBLIC (x))
3391 error ("global register variable `%s' used in nested function",
3392 IDENTIFIER_POINTER (DECL_NAME (x)));
3395 pedwarn ("register variable `%s' used in nested function",
3396 IDENTIFIER_POINTER (DECL_NAME (x)));
3398 else if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x))
3400 if (TREE_PUBLIC (x))
3402 error ("address of global register variable `%s' requested",
3403 IDENTIFIER_POINTER (DECL_NAME (x)));
3407 /* If we are making this addressable due to its having
3408 volatile components, give a different error message. Also
3409 handle the case of an unnamed parameter by not trying
3410 to give the name. */
3412 else if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (x)))
3414 error ("cannot put object with volatile field into register");
3418 pedwarn ("address of register variable `%s' requested",
3419 IDENTIFIER_POINTER (DECL_NAME (x)));
3421 put_var_into_stack (x);
3425 TREE_ADDRESSABLE (x) = 1;
3426 #if 0 /* poplevel deals with this now. */
3427 if (DECL_CONTEXT (x) == 0)
3428 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
3436 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3439 build_conditional_expr (ifexp, op1, op2)
3440 tree ifexp, op1, op2;
3442 register tree type1;
3443 register tree type2;
3444 register enum tree_code code1;
3445 register enum tree_code code2;
3446 register tree result_type = NULL;
3447 tree orig_op1 = op1, orig_op2 = op2;
3449 ifexp = truthvalue_conversion (default_conversion (ifexp));
3451 #if 0 /* Produces wrong result if within sizeof. */
3452 /* Don't promote the operands separately if they promote
3453 the same way. Return the unpromoted type and let the combined
3454 value get promoted if necessary. */
3456 if (TREE_TYPE (op1) == TREE_TYPE (op2)
3457 && TREE_CODE (TREE_TYPE (op1)) != ARRAY_TYPE
3458 && TREE_CODE (TREE_TYPE (op1)) != ENUMERAL_TYPE
3459 && TREE_CODE (TREE_TYPE (op1)) != FUNCTION_TYPE)
3461 if (TREE_CODE (ifexp) == INTEGER_CST)
3462 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3464 return fold (build (COND_EXPR, TREE_TYPE (op1), ifexp, op1, op2));
3468 /* Promote both alternatives. */
3470 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3471 op1 = default_conversion (op1);
3472 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3473 op2 = default_conversion (op2);
3475 if (TREE_CODE (ifexp) == ERROR_MARK
3476 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3477 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3478 return error_mark_node;
3480 type1 = TREE_TYPE (op1);
3481 code1 = TREE_CODE (type1);
3482 type2 = TREE_TYPE (op2);
3483 code2 = TREE_CODE (type2);
3485 /* Quickly detect the usual case where op1 and op2 have the same type
3487 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3490 result_type = type1;
3492 result_type = TYPE_MAIN_VARIANT (type1);
3494 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3495 || code1 == COMPLEX_TYPE)
3496 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3497 || code2 == COMPLEX_TYPE))
3499 result_type = common_type (type1, type2);
3501 /* If -Wsign-compare, warn here if type1 and type2 have
3502 different signedness. We'll promote the signed to unsigned
3503 and later code won't know it used to be different.
3504 Do this check on the original types, so that explicit casts
3505 will be considered, but default promotions won't. */
3506 if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare)
3507 && !skip_evaluation)
3509 int unsigned_op1 = TREE_UNSIGNED (TREE_TYPE (orig_op1));
3510 int unsigned_op2 = TREE_UNSIGNED (TREE_TYPE (orig_op2));
3512 if (unsigned_op1 ^ unsigned_op2)
3514 /* Do not warn if the result type is signed, since the
3515 signed type will only be chosen if it can represent
3516 all the values of the unsigned type. */
3517 if (! TREE_UNSIGNED (result_type))
3519 /* Do not warn if the signed quantity is an unsuffixed
3520 integer literal (or some static constant expression
3521 involving such literals) and it is non-negative. */
3522 else if ((unsigned_op2 && tree_expr_nonnegative_p (op1))
3523 || (unsigned_op1 && tree_expr_nonnegative_p (op2)))
3526 warning ("signed and unsigned type in conditional expression");
3530 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3532 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3533 pedwarn ("ISO C forbids conditional expr with only one void side");
3534 result_type = void_type_node;
3536 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3538 if (comp_target_types (type1, type2))
3539 result_type = common_type (type1, type2);
3540 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
3541 && TREE_CODE (orig_op1) != NOP_EXPR)
3542 result_type = qualify_type (type2, type1);
3543 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
3544 && TREE_CODE (orig_op2) != NOP_EXPR)
3545 result_type = qualify_type (type1, type2);
3546 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3548 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3549 pedwarn ("ISO C forbids conditional expr between `void *' and function pointer");
3550 result_type = qualify_type (type1, type2);
3552 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3554 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3555 pedwarn ("ISO C forbids conditional expr between `void *' and function pointer");
3556 result_type = qualify_type (type2, type1);
3560 pedwarn ("pointer type mismatch in conditional expression");
3561 result_type = build_pointer_type (void_type_node);
3564 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3566 if (! integer_zerop (op2))
3567 pedwarn ("pointer/integer type mismatch in conditional expression");
3570 op2 = null_pointer_node;
3571 #if 0 /* The spec seems to say this is permitted. */
3572 if (pedantic && TREE_CODE (type1) == FUNCTION_TYPE)
3573 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3576 result_type = type1;
3578 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3580 if (!integer_zerop (op1))
3581 pedwarn ("pointer/integer type mismatch in conditional expression");
3584 op1 = null_pointer_node;
3585 #if 0 /* The spec seems to say this is permitted. */
3586 if (pedantic && TREE_CODE (type2) == FUNCTION_TYPE)
3587 pedwarn ("ANSI C forbids conditional expr between 0 and function pointer");
3590 result_type = type2;
3595 if (flag_cond_mismatch)
3596 result_type = void_type_node;
3599 error ("type mismatch in conditional expression");
3600 return error_mark_node;
3604 /* Merge const and volatile flags of the incoming types. */
3606 = build_type_variant (result_type,
3607 TREE_READONLY (op1) || TREE_READONLY (op2),
3608 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3610 if (result_type != TREE_TYPE (op1))
3611 op1 = convert_and_check (result_type, op1);
3612 if (result_type != TREE_TYPE (op2))
3613 op2 = convert_and_check (result_type, op2);
3615 if (TREE_CODE (ifexp) == INTEGER_CST)
3616 return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3618 return fold (build (COND_EXPR, result_type, ifexp, op1, op2));
3621 /* Given a list of expressions, return a compound expression
3622 that performs them all and returns the value of the last of them. */
3625 build_compound_expr (list)
3628 return internal_build_compound_expr (list, TRUE);
3632 internal_build_compound_expr (list, first_p)
3638 if (TREE_CHAIN (list) == 0)
3640 #if 0 /* If something inside inhibited lvalueness, we should not override. */
3641 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3643 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3644 if (TREE_CODE (list) == NON_LVALUE_EXPR)
3645 list = TREE_OPERAND (list, 0);
3648 /* Don't let (0, 0) be null pointer constant. */
3649 if (!first_p && integer_zerop (TREE_VALUE (list)))
3650 return non_lvalue (TREE_VALUE (list));
3651 return TREE_VALUE (list);
3654 if (TREE_CHAIN (list) != 0 && TREE_CHAIN (TREE_CHAIN (list)) == 0)
3656 /* Convert arrays to pointers when there really is a comma operator. */
3657 if (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (list)))) == ARRAY_TYPE)
3658 TREE_VALUE (TREE_CHAIN (list))
3659 = default_conversion (TREE_VALUE (TREE_CHAIN (list)));
3662 rest = internal_build_compound_expr (TREE_CHAIN (list), FALSE);
3664 if (! TREE_SIDE_EFFECTS (TREE_VALUE (list)))
3666 /* The left-hand operand of a comma expression is like an expression
3667 statement: with -W or -Wunused, we should warn if it doesn't have
3668 any side-effects, unless it was explicitly cast to (void). */
3669 if ((extra_warnings || warn_unused_value)
3670 && ! (TREE_CODE (TREE_VALUE (list)) == CONVERT_EXPR
3671 && VOID_TYPE_P (TREE_TYPE (TREE_VALUE (list)))))
3672 warning ("left-hand operand of comma expression has no effect");
3674 /* When pedantic, a compound expression can be neither an lvalue
3675 nor an integer constant expression. */
3680 /* With -Wunused, we should also warn if the left-hand operand does have
3681 side-effects, but computes a value which is not used. For example, in
3682 `foo() + bar(), baz()' the result of the `+' operator is not used,
3683 so we should issue a warning. */
3684 else if (warn_unused_value)
3685 warn_if_unused_value (TREE_VALUE (list));
3687 return build (COMPOUND_EXPR, TREE_TYPE (rest), TREE_VALUE (list), rest);
3690 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3693 build_c_cast (type, expr)
3697 register tree value = expr;
3699 if (type == error_mark_node || expr == error_mark_node)
3700 return error_mark_node;
3701 type = TYPE_MAIN_VARIANT (type);
3704 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3705 if (TREE_CODE (value) == NON_LVALUE_EXPR)
3706 value = TREE_OPERAND (value, 0);
3709 if (TREE_CODE (type) == ARRAY_TYPE)
3711 error ("cast specifies array type");
3712 return error_mark_node;
3715 if (TREE_CODE (type) == FUNCTION_TYPE)
3717 error ("cast specifies function type");
3718 return error_mark_node;
3721 if (type == TREE_TYPE (value))
3725 if (TREE_CODE (type) == RECORD_TYPE
3726 || TREE_CODE (type) == UNION_TYPE)
3727 pedwarn ("ISO C forbids casting nonscalar to the same type");
3730 else if (TREE_CODE (type) == UNION_TYPE)
3733 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
3734 || TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE)
3735 value = default_conversion (value);
3737 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3738 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3739 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3748 pedwarn ("ISO C forbids casts to union type");
3749 if (TYPE_NAME (type) != 0)
3751 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
3752 name = IDENTIFIER_POINTER (TYPE_NAME (type));
3754 name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));
3758 t = digest_init (type, build (CONSTRUCTOR, type, NULL_TREE,
3759 build_tree_list (field, value)),
3761 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3764 error ("cast to union type from type not present in union");
3765 return error_mark_node;
3771 /* If casting to void, avoid the error that would come
3772 from default_conversion in the case of a non-lvalue array. */
3773 if (type == void_type_node)
3774 return build1 (CONVERT_EXPR, type, value);
3776 /* Convert functions and arrays to pointers,
3777 but don't convert any other types. */
3778 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
3779 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE)
3780 value = default_conversion (value);
3781 otype = TREE_TYPE (value);
3783 /* Optionally warn about potentially worrisome casts. */
3786 && TREE_CODE (type) == POINTER_TYPE
3787 && TREE_CODE (otype) == POINTER_TYPE)
3789 tree in_type = type;
3790 tree in_otype = otype;
3793 /* Check that the qualifiers on IN_TYPE are a superset of
3794 the qualifiers of IN_OTYPE. The outermost level of
3795 POINTER_TYPE nodes is uninteresting and we stop as soon
3796 as we hit a non-POINTER_TYPE node on either type. */
3799 in_otype = TREE_TYPE (in_otype);
3800 in_type = TREE_TYPE (in_type);
3801 warn |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3803 while (TREE_CODE (in_type) == POINTER_TYPE
3804 && TREE_CODE (in_otype) == POINTER_TYPE);
3807 /* There are qualifiers present in IN_OTYPE that are not
3808 present in IN_TYPE. */
3809 warning ("cast discards qualifiers from pointer target type");
3812 /* Warn about possible alignment problems. */
3813 if (STRICT_ALIGNMENT && warn_cast_align
3814 && TREE_CODE (type) == POINTER_TYPE
3815 && TREE_CODE (otype) == POINTER_TYPE
3816 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3817 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3818 /* Don't warn about opaque types, where the actual alignment
3819 restriction is unknown. */
3820 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3821 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3822 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3823 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3824 warning ("cast increases required alignment of target type");
3826 if (TREE_CODE (type) == INTEGER_TYPE
3827 && TREE_CODE (otype) == POINTER_TYPE
3828 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3829 && !TREE_CONSTANT (value))
3830 warning ("cast from pointer to integer of different size");
3832 if (warn_bad_function_cast
3833 && TREE_CODE (value) == CALL_EXPR
3834 && TREE_CODE (type) != TREE_CODE (otype))
3835 warning ("cast does not match function type");
3837 if (TREE_CODE (type) == POINTER_TYPE
3838 && TREE_CODE (otype) == INTEGER_TYPE
3839 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3840 /* Don't warn about converting any constant. */
3841 && !TREE_CONSTANT (value))
3842 warning ("cast to pointer from integer of different size");
3845 value = convert (type, value);
3847 /* Ignore any integer overflow caused by the cast. */
3848 if (TREE_CODE (value) == INTEGER_CST)
3850 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3851 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3855 /* Pedantically, don't ley (void *) (FOO *) 0 be a null pointer constant. */
3856 if (pedantic && TREE_CODE (value) == INTEGER_CST
3857 && TREE_CODE (expr) == INTEGER_CST
3858 && TREE_CODE (TREE_TYPE (expr)) != INTEGER_TYPE)
3859 value = non_lvalue (value);
3861 /* If pedantic, don't let a cast be an lvalue. */
3862 if (value == expr && pedantic)
3863 value = non_lvalue (value);
3868 /* Build an assignment expression of lvalue LHS from value RHS.
3869 MODIFYCODE is the code for a binary operator that we use
3870 to combine the old value of LHS with RHS to get the new value.
3871 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3874 build_modify_expr (lhs, modifycode, rhs)
3876 enum tree_code modifycode;
3878 register tree result;
3880 tree lhstype = TREE_TYPE (lhs);
3881 tree olhstype = lhstype;
3883 /* Types that aren't fully specified cannot be used in assignments. */
3884 lhs = require_complete_type (lhs);
3886 /* Avoid duplicate error messages from operands that had errors. */
3887 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3888 return error_mark_node;
3890 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3891 /* Do not use STRIP_NOPS here. We do not want an enumerator
3892 whose value is 0 to count as a null pointer constant. */
3893 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3894 rhs = TREE_OPERAND (rhs, 0);
3898 /* Handle control structure constructs used as "lvalues". */
3900 switch (TREE_CODE (lhs))
3902 /* Handle (a, b) used as an "lvalue". */
3904 pedantic_lvalue_warning (COMPOUND_EXPR);
3905 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1), modifycode, rhs);
3906 if (TREE_CODE (newrhs) == ERROR_MARK)
3907 return error_mark_node;
3908 return build (COMPOUND_EXPR, lhstype,
3909 TREE_OPERAND (lhs, 0), newrhs);
3911 /* Handle (a ? b : c) used as an "lvalue". */
3913 pedantic_lvalue_warning (COND_EXPR);
3914 rhs = save_expr (rhs);
3916 /* Produce (a ? (b = rhs) : (c = rhs))
3917 except that the RHS goes through a save-expr
3918 so the code to compute it is only emitted once. */
3920 = build_conditional_expr (TREE_OPERAND (lhs, 0),
3921 build_modify_expr (TREE_OPERAND (lhs, 1),
3923 build_modify_expr (TREE_OPERAND (lhs, 2),
3925 if (TREE_CODE (cond) == ERROR_MARK)
3927 /* Make sure the code to compute the rhs comes out
3928 before the split. */
3929 return build (COMPOUND_EXPR, TREE_TYPE (lhs),
3930 /* But cast it to void to avoid an "unused" error. */
3931 convert (void_type_node, rhs), cond);
3937 /* If a binary op has been requested, combine the old LHS value with the RHS
3938 producing the value we should actually store into the LHS. */
3940 if (modifycode != NOP_EXPR)
3942 lhs = stabilize_reference (lhs);
3943 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3946 /* Handle a cast used as an "lvalue".
3947 We have already performed any binary operator using the value as cast.
3948 Now convert the result to the cast type of the lhs,
3949 and then true type of the lhs and store it there;
3950 then convert result back to the cast type to be the value
3951 of the assignment. */
3953 switch (TREE_CODE (lhs))
3958 case FIX_TRUNC_EXPR:
3959 case FIX_FLOOR_EXPR:
3960 case FIX_ROUND_EXPR:
3962 if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
3963 || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE)
3964 newrhs = default_conversion (newrhs);
3966 tree inner_lhs = TREE_OPERAND (lhs, 0);
3968 result = build_modify_expr (inner_lhs, NOP_EXPR,
3969 convert (TREE_TYPE (inner_lhs),
3970 convert (lhstype, newrhs)));
3971 if (TREE_CODE (result) == ERROR_MARK)
3973 pedantic_lvalue_warning (CONVERT_EXPR);
3974 return convert (TREE_TYPE (lhs), result);
3981 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3982 Reject anything strange now. */
3984 if (!lvalue_or_else (lhs, "invalid lvalue in assignment"))
3985 return error_mark_node;
3987 /* Warn about storing in something that is `const'. */
3989 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3990 || ((TREE_CODE (lhstype) == RECORD_TYPE
3991 || TREE_CODE (lhstype) == UNION_TYPE)
3992 && C_TYPE_FIELDS_READONLY (lhstype)))
3993 readonly_warning (lhs, "assignment");
3995 /* If storing into a structure or union member,
3996 it has probably been given type `int'.
3997 Compute the type that would go with
3998 the actual amount of storage the member occupies. */
4000 if (TREE_CODE (lhs) == COMPONENT_REF
4001 && (TREE_CODE (lhstype) == INTEGER_TYPE
4002 || TREE_CODE (lhstype) == BOOLEAN_TYPE
4003 || TREE_CODE (lhstype) == REAL_TYPE
4004 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
4005 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
4007 /* If storing in a field that is in actuality a short or narrower than one,
4008 we must store in the field in its actual type. */
4010 if (lhstype != TREE_TYPE (lhs))
4012 lhs = copy_node (lhs);
4013 TREE_TYPE (lhs) = lhstype;
4016 /* Convert new value to destination type. */
4018 newrhs = convert_for_assignment (lhstype, newrhs, _("assignment"),
4019 NULL_TREE, NULL_TREE, 0);
4020 if (TREE_CODE (newrhs) == ERROR_MARK)
4021 return error_mark_node;
4025 result = build (MODIFY_EXPR, lhstype, lhs, newrhs);
4026 TREE_SIDE_EFFECTS (result) = 1;
4028 /* If we got the LHS in a different type for storing in,
4029 convert the result back to the nominal type of LHS
4030 so that the value we return always has the same type
4031 as the LHS argument. */
4033 if (olhstype == TREE_TYPE (result))
4035 return convert_for_assignment (olhstype, result, _("assignment"),
4036 NULL_TREE, NULL_TREE, 0);
4039 /* Convert value RHS to type TYPE as preparation for an assignment
4040 to an lvalue of type TYPE.
4041 The real work of conversion is done by `convert'.
4042 The purpose of this function is to generate error messages
4043 for assignments that are not allowed in C.
4044 ERRTYPE is a string to use in error messages:
4045 "assignment", "return", etc. If it is null, this is parameter passing
4046 for a function call (and different error messages are output).
4048 FUNNAME is the name of the function being called,
4049 as an IDENTIFIER_NODE, or null.
4050 PARMNUM is the number of the argument, for printing in error messages. */
4053 convert_for_assignment (type, rhs, errtype, fundecl, funname, parmnum)
4055 const char *errtype;
4056 tree fundecl, funname;
4059 register enum tree_code codel = TREE_CODE (type);
4060 register tree rhstype;
4061 register enum tree_code coder;
4063 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4064 /* Do not use STRIP_NOPS here. We do not want an enumerator
4065 whose value is 0 to count as a null pointer constant. */
4066 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
4067 rhs = TREE_OPERAND (rhs, 0);
4069 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
4070 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
4071 rhs = default_conversion (rhs);
4072 else if (optimize && TREE_CODE (rhs) == VAR_DECL)
4073 rhs = decl_constant_value_for_broken_optimization (rhs);
4075 rhstype = TREE_TYPE (rhs);
4076 coder = TREE_CODE (rhstype);
4078 if (coder == ERROR_MARK)
4079 return error_mark_node;
4081 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
4083 overflow_warning (rhs);
4084 /* Check for Objective-C protocols. This will issue a warning if
4085 there are protocol violations. No need to use the return value. */
4086 maybe_objc_comptypes (type, rhstype, 0);
4090 if (coder == VOID_TYPE)
4092 error ("void value not ignored as it ought to be");
4093 return error_mark_node;
4095 /* A type converts to a reference to it.
4096 This code doesn't fully support references, it's just for the
4097 special case of va_start and va_copy. */
4098 if (codel == REFERENCE_TYPE
4099 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
4101 if (mark_addressable (rhs) == 0)
4102 return error_mark_node;
4103 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
4105 /* We already know that these two types are compatible, but they
4106 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4107 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4108 likely to be va_list, a typedef to __builtin_va_list, which
4109 is different enough that it will cause problems later. */
4110 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
4111 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
4113 rhs = build1 (NOP_EXPR, type, rhs);
4116 /* Arithmetic types all interconvert, and enum is treated like int. */
4117 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
4118 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
4119 || codel == BOOLEAN_TYPE)
4120 && (coder == INTEGER_TYPE || coder == REAL_TYPE
4121 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
4122 || coder == BOOLEAN_TYPE))
4123 return convert_and_check (type, rhs);
4125 /* Conversion to a transparent union from its member types.
4126 This applies only to function arguments. */
4127 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type) && ! errtype)
4130 tree marginal_memb_type = 0;
4132 for (memb_types = TYPE_FIELDS (type); memb_types;
4133 memb_types = TREE_CHAIN (memb_types))
4135 tree memb_type = TREE_TYPE (memb_types);
4137 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
4138 TYPE_MAIN_VARIANT (rhstype)))
4141 if (TREE_CODE (memb_type) != POINTER_TYPE)
4144 if (coder == POINTER_TYPE)
4146 register tree ttl = TREE_TYPE (memb_type);
4147 register tree ttr = TREE_TYPE (rhstype);
4149 /* Any non-function converts to a [const][volatile] void *
4150 and vice versa; otherwise, targets must be the same.
4151 Meanwhile, the lhs target must have all the qualifiers of
4153 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4154 || comp_target_types (memb_type, rhstype))
4156 /* If this type won't generate any warnings, use it. */
4157 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
4158 || ((TREE_CODE (ttr) == FUNCTION_TYPE
4159 && TREE_CODE (ttl) == FUNCTION_TYPE)
4160 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
4161 == TYPE_QUALS (ttr))
4162 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
4163 == TYPE_QUALS (ttl))))
4166 /* Keep looking for a better type, but remember this one. */
4167 if (! marginal_memb_type)
4168 marginal_memb_type = memb_type;
4172 /* Can convert integer zero to any pointer type. */
4173 if (integer_zerop (rhs)
4174 || (TREE_CODE (rhs) == NOP_EXPR
4175 && integer_zerop (TREE_OPERAND (rhs, 0))))
4177 rhs = null_pointer_node;
4182 if (memb_types || marginal_memb_type)
4186 /* We have only a marginally acceptable member type;
4187 it needs a warning. */
4188 register tree ttl = TREE_TYPE (marginal_memb_type);
4189 register tree ttr = TREE_TYPE (rhstype);
4191 /* Const and volatile mean something different for function
4192 types, so the usual warnings are not appropriate. */
4193 if (TREE_CODE (ttr) == FUNCTION_TYPE
4194 && TREE_CODE (ttl) == FUNCTION_TYPE)
4196 /* Because const and volatile on functions are
4197 restrictions that say the function will not do
4198 certain things, it is okay to use a const or volatile
4199 function where an ordinary one is wanted, but not
4201 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4202 warn_for_assignment ("%s makes qualified function pointer from unqualified",
4203 errtype, funname, parmnum);
4205 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4206 warn_for_assignment ("%s discards qualifiers from pointer target type",
4211 if (pedantic && ! DECL_IN_SYSTEM_HEADER (fundecl))
4212 pedwarn ("ISO C prohibits argument conversion to union type");
4214 return build1 (NOP_EXPR, type, rhs);
4218 /* Conversions among pointers */
4219 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
4220 && (coder == POINTER_TYPE || coder == REFERENCE_TYPE))
4222 register tree ttl = TREE_TYPE (type);
4223 register tree ttr = TREE_TYPE (rhstype);
4225 /* Any non-function converts to a [const][volatile] void *
4226 and vice versa; otherwise, targets must be the same.
4227 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4228 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4229 || comp_target_types (type, rhstype)
4230 || (unsigned_type (TYPE_MAIN_VARIANT (ttl))
4231 == unsigned_type (TYPE_MAIN_VARIANT (ttr))))
4234 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
4237 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4238 which are not ANSI null ptr constants. */
4239 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
4240 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4241 warn_for_assignment ("ISO C forbids %s between function pointer and `void *'",
4242 errtype, funname, parmnum);
4243 /* Const and volatile mean something different for function types,
4244 so the usual warnings are not appropriate. */
4245 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4246 && TREE_CODE (ttl) != FUNCTION_TYPE)
4248 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4249 warn_for_assignment ("%s discards qualifiers from pointer target type",
4250 errtype, funname, parmnum);
4251 /* If this is not a case of ignoring a mismatch in signedness,
4253 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4254 || comp_target_types (type, rhstype))
4256 /* If there is a mismatch, do warn. */
4258 warn_for_assignment ("pointer targets in %s differ in signedness",
4259 errtype, funname, parmnum);
4261 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4262 && TREE_CODE (ttr) == FUNCTION_TYPE)
4264 /* Because const and volatile on functions are restrictions
4265 that say the function will not do certain things,
4266 it is okay to use a const or volatile function
4267 where an ordinary one is wanted, but not vice-versa. */
4268 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4269 warn_for_assignment ("%s makes qualified function pointer from unqualified",
4270 errtype, funname, parmnum);
4274 warn_for_assignment ("%s from incompatible pointer type",
4275 errtype, funname, parmnum);
4276 return convert (type, rhs);
4278 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4280 /* An explicit constant 0 can convert to a pointer,
4281 or one that results from arithmetic, even including
4282 a cast to integer type. */
4283 if (! (TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
4285 ! (TREE_CODE (rhs) == NOP_EXPR
4286 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
4287 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
4288 && integer_zerop (TREE_OPERAND (rhs, 0))))
4290 warn_for_assignment ("%s makes pointer from integer without a cast",
4291 errtype, funname, parmnum);
4292 return convert (type, rhs);
4294 return null_pointer_node;
4296 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4298 warn_for_assignment ("%s makes integer from pointer without a cast",
4299 errtype, funname, parmnum);
4300 return convert (type, rhs);
4302 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
4303 return convert (type, rhs);
4309 tree selector = maybe_building_objc_message_expr ();
4311 if (selector && parmnum > 2)
4312 error ("incompatible type for argument %d of `%s'",
4313 parmnum - 2, IDENTIFIER_POINTER (selector));
4315 error ("incompatible type for argument %d of `%s'",
4316 parmnum, IDENTIFIER_POINTER (funname));
4319 error ("incompatible type for argument %d of indirect function call",
4323 error ("incompatible types in %s", errtype);
4325 return error_mark_node;
4328 /* Print a warning using MSGID.
4329 It gets OPNAME as its one parameter.
4330 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4331 FUNCTION and ARGNUM are handled specially if we are building an
4332 Objective-C selector. */
4335 warn_for_assignment (msgid, opname, function, argnum)
4343 tree selector = maybe_building_objc_message_expr ();
4346 if (selector && argnum > 2)
4348 function = selector;
4353 /* Function name is known; supply it. */
4354 const char *argstring = _("passing arg %d of `%s'");
4355 new_opname = (char *) alloca (IDENTIFIER_LENGTH (function)
4356 + strlen (argstring) + 1 + 25
4358 sprintf (new_opname, argstring, argnum,
4359 IDENTIFIER_POINTER (function));
4363 /* Function name unknown (call through ptr); just give arg number.*/
4364 const char *argnofun = _("passing arg %d of pointer to function");
4365 new_opname = (char *) alloca (strlen (argnofun) + 1 + 25 /*%d*/ + 1);
4366 sprintf (new_opname, argnofun, argnum);
4368 opname = new_opname;
4370 pedwarn (msgid, opname);
4373 /* If VALUE is a compound expr all of whose expressions are constant, then
4374 return its value. Otherwise, return error_mark_node.
4376 This is for handling COMPOUND_EXPRs as initializer elements
4377 which is allowed with a warning when -pedantic is specified. */
4380 valid_compound_expr_initializer (value, endtype)
4384 if (TREE_CODE (value) == COMPOUND_EXPR)
4386 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4388 return error_mark_node;
4389 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4392 else if (! TREE_CONSTANT (value)
4393 && ! initializer_constant_valid_p (value, endtype))
4394 return error_mark_node;
4399 /* Perform appropriate conversions on the initial value of a variable,
4400 store it in the declaration DECL,
4401 and print any error messages that are appropriate.
4402 If the init is invalid, store an ERROR_MARK. */
4405 store_init_value (decl, init)
4408 register tree value, type;
4410 /* If variable's type was invalidly declared, just ignore it. */
4412 type = TREE_TYPE (decl);
4413 if (TREE_CODE (type) == ERROR_MARK)
4416 /* Digest the specified initializer into an expression. */
4418 value = digest_init (type, init, TREE_STATIC (decl),
4419 TREE_STATIC (decl) || pedantic);
4421 /* Store the expression if valid; else report error. */
4424 /* Note that this is the only place we can detect the error
4425 in a case such as struct foo bar = (struct foo) { x, y };
4426 where there is one initial value which is a constructor expression. */
4427 if (value == error_mark_node)
4429 else if (TREE_STATIC (decl) && ! TREE_CONSTANT (value))
4431 error ("initializer for static variable is not constant");
4432 value = error_mark_node;
4434 else if (TREE_STATIC (decl)
4435 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
4437 error ("initializer for static variable uses complicated arithmetic");
4438 value = error_mark_node;
4442 if (pedantic && TREE_CODE (value) == CONSTRUCTOR)
4444 if (! TREE_CONSTANT (value))
4445 pedwarn ("aggregate initializer is not constant");
4446 else if (! TREE_STATIC (value))
4447 pedwarn ("aggregate initializer uses complicated arithmetic");
4452 if (warn_traditional && !in_system_header
4453 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && ! TREE_STATIC (decl))
4454 warning ("traditional C rejects automatic aggregate initialization");
4456 DECL_INITIAL (decl) = value;
4458 /* ANSI wants warnings about out-of-range constant initializers. */
4459 STRIP_TYPE_NOPS (value);
4460 constant_expression_warning (value);
4463 /* Methods for storing and printing names for error messages. */
4465 /* Implement a spelling stack that allows components of a name to be pushed
4466 and popped. Each element on the stack is this structure. */
4478 #define SPELLING_STRING 1
4479 #define SPELLING_MEMBER 2
4480 #define SPELLING_BOUNDS 3
4482 static struct spelling *spelling; /* Next stack element (unused). */
4483 static struct spelling *spelling_base; /* Spelling stack base. */
4484 static int spelling_size; /* Size of the spelling stack. */
4486 /* Macros to save and restore the spelling stack around push_... functions.
4487 Alternative to SAVE_SPELLING_STACK. */
4489 #define SPELLING_DEPTH() (spelling - spelling_base)
4490 #define RESTORE_SPELLING_DEPTH(depth) (spelling = spelling_base + depth)
4492 /* Save and restore the spelling stack around arbitrary C code. */
4494 #define SAVE_SPELLING_DEPTH(code) \
4496 int __depth = SPELLING_DEPTH (); \
4498 RESTORE_SPELLING_DEPTH (__depth); \
4501 /* Push an element on the spelling stack with type KIND and assign VALUE
4504 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4506 int depth = SPELLING_DEPTH (); \
4508 if (depth >= spelling_size) \
4510 spelling_size += 10; \
4511 if (spelling_base == 0) \
4513 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4516 = (struct spelling *) xrealloc (spelling_base, \
4517 spelling_size * sizeof (struct spelling)); \
4518 RESTORE_SPELLING_DEPTH (depth); \
4521 spelling->kind = (KIND); \
4522 spelling->MEMBER = (VALUE); \
4526 /* Push STRING on the stack. Printed literally. */
4529 push_string (string)
4532 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4535 /* Push a member name on the stack. Printed as '.' STRING. */
4538 push_member_name (decl)
4543 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4544 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4547 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4550 push_array_bounds (bounds)
4553 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4556 /* Compute the maximum size in bytes of the printed spelling. */
4561 register int size = 0;
4562 register struct spelling *p;
4564 for (p = spelling_base; p < spelling; p++)
4566 if (p->kind == SPELLING_BOUNDS)
4569 size += strlen (p->u.s) + 1;
4575 /* Print the spelling to BUFFER and return it. */
4578 print_spelling (buffer)
4579 register char *buffer;
4581 register char *d = buffer;
4582 register struct spelling *p;
4584 for (p = spelling_base; p < spelling; p++)
4585 if (p->kind == SPELLING_BOUNDS)
4587 sprintf (d, "[%d]", p->u.i);
4592 register const char *s;
4593 if (p->kind == SPELLING_MEMBER)
4595 for (s = p->u.s; (*d = *s++); d++)
4602 /* Issue an error message for a bad initializer component.
4603 MSGID identifies the message.
4604 The component name is taken from the spelling stack. */
4612 error ("%s", msgid);
4613 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4615 error ("(near initialization for `%s')", ofwhat);
4618 /* Issue a pedantic warning for a bad initializer component.
4619 MSGID identifies the message.
4620 The component name is taken from the spelling stack. */
4623 pedwarn_init (msgid)
4628 pedwarn ("%s", msgid);
4629 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4631 pedwarn ("(near initialization for `%s')", ofwhat);
4634 /* Issue a warning for a bad initializer component.
4635 MSGID identifies the message.
4636 The component name is taken from the spelling stack. */
4639 warning_init (msgid)
4644 warning ("%s", msgid);
4645 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4647 warning ("(near initialization for `%s')", ofwhat);
4650 /* Digest the parser output INIT as an initializer for type TYPE.
4651 Return a C expression of type TYPE to represent the initial value.
4653 The arguments REQUIRE_CONSTANT and CONSTRUCTOR_CONSTANT request errors
4654 if non-constant initializers or elements are seen. CONSTRUCTOR_CONSTANT
4655 applies only to elements of constructors. */
4658 digest_init (type, init, require_constant, constructor_constant)
4660 int require_constant, constructor_constant;
4662 enum tree_code code = TREE_CODE (type);
4663 tree inside_init = init;
4665 if (type == error_mark_node
4666 || init == error_mark_node
4667 || TREE_TYPE (init) == error_mark_node)
4668 return error_mark_node;
4670 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4671 /* Do not use STRIP_NOPS here. We do not want an enumerator
4672 whose value is 0 to count as a null pointer constant. */
4673 if (TREE_CODE (init) == NON_LVALUE_EXPR)
4674 inside_init = TREE_OPERAND (init, 0);
4676 /* Initialization of an array of chars from a string constant
4677 optionally enclosed in braces. */
4679 if (code == ARRAY_TYPE)
4681 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4682 if ((typ1 == char_type_node
4683 || typ1 == signed_char_type_node
4684 || typ1 == unsigned_char_type_node
4685 || typ1 == unsigned_wchar_type_node
4686 || typ1 == signed_wchar_type_node)
4687 && ((inside_init && TREE_CODE (inside_init) == STRING_CST)))
4689 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4690 TYPE_MAIN_VARIANT (type)))
4693 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4695 && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node))
4697 error_init ("char-array initialized from wide string");
4698 return error_mark_node;
4700 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4702 && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node))
4704 error_init ("int-array initialized from non-wide string");
4705 return error_mark_node;
4708 TREE_TYPE (inside_init) = type;
4709 if (TYPE_DOMAIN (type) != 0
4710 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4711 /* Subtract 1 (or sizeof (wchar_t))
4712 because it's ok to ignore the terminating null char
4713 that is counted in the length of the constant. */
4714 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4715 TREE_STRING_LENGTH (inside_init)
4716 - ((TYPE_PRECISION (typ1)
4717 != TYPE_PRECISION (char_type_node))
4718 ? (TYPE_PRECISION (wchar_type_node)
4721 pedwarn_init ("initializer-string for array of chars is too long");
4727 /* Any type can be initialized
4728 from an expression of the same type, optionally with braces. */
4730 if (inside_init && TREE_TYPE (inside_init) != 0
4731 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4732 TYPE_MAIN_VARIANT (type))
4733 || (code == ARRAY_TYPE
4734 && comptypes (TREE_TYPE (inside_init), type))
4735 || (code == POINTER_TYPE
4736 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4737 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE)
4738 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4739 TREE_TYPE (type)))))
4741 if (code == POINTER_TYPE
4742 && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4743 || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE))
4744 inside_init = default_conversion (inside_init);
4745 else if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4746 && TREE_CODE (inside_init) != CONSTRUCTOR)
4748 error_init ("array initialized from non-constant array expression");
4749 return error_mark_node;
4752 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4753 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4755 /* Compound expressions can only occur here if -pedantic or
4756 -pedantic-errors is specified. In the later case, we always want
4757 an error. In the former case, we simply want a warning. */
4758 if (require_constant && pedantic
4759 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4762 = valid_compound_expr_initializer (inside_init,
4763 TREE_TYPE (inside_init));
4764 if (inside_init == error_mark_node)
4765 error_init ("initializer element is not constant");
4767 pedwarn_init ("initializer element is not constant");
4768 if (flag_pedantic_errors)
4769 inside_init = error_mark_node;
4771 else if (require_constant && ! TREE_CONSTANT (inside_init))
4773 error_init ("initializer element is not constant");
4774 inside_init = error_mark_node;
4776 else if (require_constant
4777 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4779 error_init ("initializer element is not computable at load time");
4780 inside_init = error_mark_node;
4786 /* Handle scalar types, including conversions. */
4788 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4789 || code == ENUMERAL_TYPE || code == COMPLEX_TYPE)
4791 /* Note that convert_for_assignment calls default_conversion
4792 for arrays and functions. We must not call it in the
4793 case where inside_init is a null pointer constant. */
4795 = convert_for_assignment (type, init, _("initialization"),
4796 NULL_TREE, NULL_TREE, 0);
4798 if (require_constant && ! TREE_CONSTANT (inside_init))
4800 error_init ("initializer element is not constant");
4801 inside_init = error_mark_node;
4803 else if (require_constant
4804 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4806 error_init ("initializer element is not computable at load time");
4807 inside_init = error_mark_node;
4813 /* Come here only for records and arrays. */
4815 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4817 error_init ("variable-sized object may not be initialized");
4818 return error_mark_node;
4821 /* Traditionally, you can write struct foo x = 0;
4822 and it initializes the first element of x to 0. */
4823 if (flag_traditional)
4825 tree top = 0, prev = 0, otype = type;
4826 while (TREE_CODE (type) == RECORD_TYPE
4827 || TREE_CODE (type) == ARRAY_TYPE
4828 || TREE_CODE (type) == QUAL_UNION_TYPE
4829 || TREE_CODE (type) == UNION_TYPE)
4831 tree temp = build (CONSTRUCTOR, type, NULL_TREE, NULL_TREE);
4835 TREE_OPERAND (prev, 1) = build_tree_list (NULL_TREE, temp);
4837 if (TREE_CODE (type) == ARRAY_TYPE)
4838 type = TREE_TYPE (type);
4839 else if (TYPE_FIELDS (type))
4840 type = TREE_TYPE (TYPE_FIELDS (type));
4843 error_init ("invalid initializer");
4844 return error_mark_node;
4850 TREE_OPERAND (prev, 1)
4851 = build_tree_list (NULL_TREE,
4852 digest_init (type, init, require_constant,
4853 constructor_constant));
4857 return error_mark_node;
4859 error_init ("invalid initializer");
4860 return error_mark_node;
4863 /* Handle initializers that use braces. */
4865 /* Type of object we are accumulating a constructor for.
4866 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4867 static tree constructor_type;
4869 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4871 static tree constructor_fields;
4873 /* For an ARRAY_TYPE, this is the specified index
4874 at which to store the next element we get. */
4875 static tree constructor_index;
4877 /* For an ARRAY_TYPE, this is the end index of the range
4878 to initialize with the next element, or NULL in the ordinary case
4879 where the element is used just once. */
4880 static tree constructor_range_end;
4882 /* For an ARRAY_TYPE, this is the maximum index. */
4883 static tree constructor_max_index;
4885 /* For a RECORD_TYPE, this is the first field not yet written out. */
4886 static tree constructor_unfilled_fields;
4888 /* For an ARRAY_TYPE, this is the index of the first element
4889 not yet written out. */
4890 static tree constructor_unfilled_index;
4892 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4893 This is so we can generate gaps between fields, when appropriate. */
4894 static tree constructor_bit_index;
4896 /* If we are saving up the elements rather than allocating them,
4897 this is the list of elements so far (in reverse order,
4898 most recent first). */
4899 static tree constructor_elements;
4901 /* 1 if so far this constructor's elements are all compile-time constants. */
4902 static int constructor_constant;
4904 /* 1 if so far this constructor's elements are all valid address constants. */
4905 static int constructor_simple;
4907 /* 1 if this constructor is erroneous so far. */
4908 static int constructor_erroneous;
4910 /* 1 if have called defer_addressed_constants. */
4911 static int constructor_subconstants_deferred;
4913 /* Structure for managing pending initializer elements, organized as an
4918 struct init_node *left, *right;
4919 struct init_node *parent;
4925 /* Tree of pending elements at this constructor level.
4926 These are elements encountered out of order
4927 which belong at places we haven't reached yet in actually
4929 Will never hold tree nodes across GC runs. */
4930 static struct init_node *constructor_pending_elts;
4932 /* The SPELLING_DEPTH of this constructor. */
4933 static int constructor_depth;
4935 /* 0 if implicitly pushing constructor levels is allowed. */
4936 int constructor_no_implicit = 0; /* 0 for C; 1 for some other languages. */
4938 static int require_constant_value;
4939 static int require_constant_elements;
4941 /* DECL node for which an initializer is being read.
4942 0 means we are reading a constructor expression
4943 such as (struct foo) {...}. */
4944 static tree constructor_decl;
4946 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4947 static char *constructor_asmspec;
4949 /* Nonzero if this is an initializer for a top-level decl. */
4950 static int constructor_top_level;
4953 /* This stack has a level for each implicit or explicit level of
4954 structuring in the initializer, including the outermost one. It
4955 saves the values of most of the variables above. */
4957 struct constructor_stack
4959 struct constructor_stack *next;
4965 tree unfilled_index;
4966 tree unfilled_fields;
4970 struct init_node *pending_elts;
4972 /* If nonzero, this value should replace the entire
4973 constructor at this level. */
4974 tree replacement_value;
4982 struct constructor_stack *constructor_stack;
4984 /* This stack records separate initializers that are nested.
4985 Nested initializers can't happen in ANSI C, but GNU C allows them
4986 in cases like { ... (struct foo) { ... } ... }. */
4988 struct initializer_stack
4990 struct initializer_stack *next;
4993 struct constructor_stack *constructor_stack;
4995 struct spelling *spelling;
4996 struct spelling *spelling_base;
4999 char require_constant_value;
5000 char require_constant_elements;
5004 struct initializer_stack *initializer_stack;
5006 /* Prepare to parse and output the initializer for variable DECL. */
5009 start_init (decl, asmspec_tree, top_level)
5015 struct initializer_stack *p
5016 = (struct initializer_stack *) xmalloc (sizeof (struct initializer_stack));
5020 asmspec = TREE_STRING_POINTER (asmspec_tree);
5022 p->decl = constructor_decl;
5023 p->asmspec = constructor_asmspec;
5024 p->require_constant_value = require_constant_value;
5025 p->require_constant_elements = require_constant_elements;
5026 p->constructor_stack = constructor_stack;
5027 p->elements = constructor_elements;
5028 p->spelling = spelling;
5029 p->spelling_base = spelling_base;
5030 p->spelling_size = spelling_size;
5031 p->deferred = constructor_subconstants_deferred;
5032 p->top_level = constructor_top_level;
5033 p->next = initializer_stack;
5034 initializer_stack = p;
5036 constructor_decl = decl;
5037 constructor_asmspec = asmspec;
5038 constructor_subconstants_deferred = 0;
5039 constructor_top_level = top_level;
5043 require_constant_value = TREE_STATIC (decl);
5044 require_constant_elements
5045 = ((TREE_STATIC (decl) || pedantic)
5046 /* For a scalar, you can always use any value to initialize,
5047 even within braces. */
5048 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
5049 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
5050 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
5051 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
5052 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
5056 require_constant_value = 0;
5057 require_constant_elements = 0;
5058 locus = "(anonymous)";
5061 constructor_stack = 0;
5063 missing_braces_mentioned = 0;
5067 RESTORE_SPELLING_DEPTH (0);
5070 push_string (locus);
5076 struct initializer_stack *p = initializer_stack;
5078 /* Output subconstants (string constants, usually)
5079 that were referenced within this initializer and saved up.
5080 Must do this if and only if we called defer_addressed_constants. */
5081 if (constructor_subconstants_deferred)
5082 output_deferred_addressed_constants ();
5084 /* Free the whole constructor stack of this initializer. */
5085 while (constructor_stack)
5087 struct constructor_stack *q = constructor_stack;
5088 constructor_stack = q->next;
5092 /* Pop back to the data of the outer initializer (if any). */
5093 constructor_decl = p->decl;
5094 constructor_asmspec = p->asmspec;
5095 require_constant_value = p->require_constant_value;
5096 require_constant_elements = p->require_constant_elements;
5097 constructor_stack = p->constructor_stack;
5098 constructor_elements = p->elements;
5099 spelling = p->spelling;
5100 spelling_base = p->spelling_base;
5101 spelling_size = p->spelling_size;
5102 constructor_subconstants_deferred = p->deferred;
5103 constructor_top_level = p->top_level;
5104 initializer_stack = p->next;
5108 /* Call here when we see the initializer is surrounded by braces.
5109 This is instead of a call to push_init_level;
5110 it is matched by a call to pop_init_level.
5112 TYPE is the type to initialize, for a constructor expression.
5113 For an initializer for a decl, TYPE is zero. */
5116 really_start_incremental_init (type)
5119 struct constructor_stack *p
5120 = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5123 type = TREE_TYPE (constructor_decl);
5125 p->type = constructor_type;
5126 p->fields = constructor_fields;
5127 p->index = constructor_index;
5128 p->range_end = constructor_range_end;
5129 p->max_index = constructor_max_index;
5130 p->unfilled_index = constructor_unfilled_index;
5131 p->unfilled_fields = constructor_unfilled_fields;
5132 p->bit_index = constructor_bit_index;
5133 p->elements = constructor_elements;
5134 p->constant = constructor_constant;
5135 p->simple = constructor_simple;
5136 p->erroneous = constructor_erroneous;
5137 p->pending_elts = constructor_pending_elts;
5138 p->depth = constructor_depth;
5139 p->replacement_value = 0;
5143 constructor_stack = p;
5145 constructor_constant = 1;
5146 constructor_simple = 1;
5147 constructor_depth = SPELLING_DEPTH ();
5148 constructor_elements = 0;
5149 constructor_pending_elts = 0;
5150 constructor_type = type;
5152 if (TREE_CODE (constructor_type) == RECORD_TYPE
5153 || TREE_CODE (constructor_type) == UNION_TYPE)
5155 constructor_fields = TYPE_FIELDS (constructor_type);
5156 /* Skip any nameless bit fields at the beginning. */
5157 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5158 && DECL_NAME (constructor_fields) == 0)
5159 constructor_fields = TREE_CHAIN (constructor_fields);
5161 constructor_unfilled_fields = constructor_fields;
5162 constructor_bit_index = bitsize_zero_node;
5164 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5166 constructor_range_end = 0;
5167 if (TYPE_DOMAIN (constructor_type))
5169 constructor_max_index
5170 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5172 = convert (bitsizetype,
5173 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5176 constructor_index = bitsize_zero_node;
5178 constructor_unfilled_index = constructor_index;
5182 /* Handle the case of int x = {5}; */
5183 constructor_fields = constructor_type;
5184 constructor_unfilled_fields = constructor_type;
5188 /* Push down into a subobject, for initialization.
5189 If this is for an explicit set of braces, IMPLICIT is 0.
5190 If it is because the next element belongs at a lower level,
5194 push_init_level (implicit)
5197 struct constructor_stack *p;
5199 /* If we've exhausted any levels that didn't have braces,
5201 while (constructor_stack->implicit)
5203 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5204 || TREE_CODE (constructor_type) == UNION_TYPE)
5205 && constructor_fields == 0)
5206 process_init_element (pop_init_level (1));
5207 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5208 && tree_int_cst_lt (constructor_max_index, constructor_index))
5209 process_init_element (pop_init_level (1));
5214 p = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack));
5215 p->type = constructor_type;
5216 p->fields = constructor_fields;
5217 p->index = constructor_index;
5218 p->range_end = constructor_range_end;
5219 p->max_index = constructor_max_index;
5220 p->unfilled_index = constructor_unfilled_index;
5221 p->unfilled_fields = constructor_unfilled_fields;
5222 p->bit_index = constructor_bit_index;
5223 p->elements = constructor_elements;
5224 p->constant = constructor_constant;
5225 p->simple = constructor_simple;
5226 p->erroneous = constructor_erroneous;
5227 p->pending_elts = constructor_pending_elts;
5228 p->depth = constructor_depth;
5229 p->replacement_value = 0;
5230 p->implicit = implicit;
5232 p->next = constructor_stack;
5233 constructor_stack = p;
5235 constructor_constant = 1;
5236 constructor_simple = 1;
5237 constructor_depth = SPELLING_DEPTH ();
5238 constructor_elements = 0;
5239 constructor_pending_elts = 0;
5241 /* Don't die if an entire brace-pair level is superfluous
5242 in the containing level. */
5243 if (constructor_type == 0)
5245 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5246 || TREE_CODE (constructor_type) == UNION_TYPE)
5248 /* Don't die if there are extra init elts at the end. */
5249 if (constructor_fields == 0)
5250 constructor_type = 0;
5253 constructor_type = TREE_TYPE (constructor_fields);
5254 push_member_name (constructor_fields);
5255 constructor_depth++;
5258 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5260 constructor_type = TREE_TYPE (constructor_type);
5261 push_array_bounds (tree_low_cst (constructor_index, 0));
5262 constructor_depth++;
5265 if (constructor_type == 0)
5267 error_init ("extra brace group at end of initializer");
5268 constructor_fields = 0;
5269 constructor_unfilled_fields = 0;
5273 if (implicit && warn_missing_braces && !missing_braces_mentioned)
5275 missing_braces_mentioned = 1;
5276 warning_init ("missing braces around initializer");
5279 if (TREE_CODE (constructor_type) == RECORD_TYPE
5280 || TREE_CODE (constructor_type) == UNION_TYPE)
5282 constructor_fields = TYPE_FIELDS (constructor_type);
5283 /* Skip any nameless bit fields at the beginning. */
5284 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5285 && DECL_NAME (constructor_fields) == 0)
5286 constructor_fields = TREE_CHAIN (constructor_fields);
5288 constructor_unfilled_fields = constructor_fields;
5289 constructor_bit_index = bitsize_zero_node;
5291 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5293 constructor_range_end = 0;
5294 if (TYPE_DOMAIN (constructor_type))
5296 constructor_max_index
5297 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5299 = convert (bitsizetype,
5301 (TYPE_DOMAIN (constructor_type)));
5304 constructor_index = bitsize_zero_node;
5306 constructor_unfilled_index = constructor_index;
5310 warning_init ("braces around scalar initializer");
5311 constructor_fields = constructor_type;
5312 constructor_unfilled_fields = constructor_type;
5316 /* At the end of an implicit or explicit brace level,
5317 finish up that level of constructor.
5318 If we were outputting the elements as they are read, return 0
5319 from inner levels (process_init_element ignores that),
5320 but return error_mark_node from the outermost level
5321 (that's what we want to put in DECL_INITIAL).
5322 Otherwise, return a CONSTRUCTOR expression. */
5325 pop_init_level (implicit)
5328 struct constructor_stack *p;
5329 HOST_WIDE_INT size = 0;
5330 tree constructor = 0;
5334 /* When we come to an explicit close brace,
5335 pop any inner levels that didn't have explicit braces. */
5336 while (constructor_stack->implicit)
5337 process_init_element (pop_init_level (1));
5340 p = constructor_stack;
5342 if (constructor_type != 0)
5343 size = int_size_in_bytes (constructor_type);
5345 /* Warn when some struct elements are implicitly initialized to zero. */
5348 && TREE_CODE (constructor_type) == RECORD_TYPE
5349 && constructor_unfilled_fields)
5351 push_member_name (constructor_unfilled_fields);
5352 warning_init ("missing initializer");
5353 RESTORE_SPELLING_DEPTH (constructor_depth);
5356 /* Now output all pending elements. */
5357 output_pending_init_elements (1);
5359 #if 0 /* c-parse.in warns about {}. */
5360 /* In ANSI, each brace level must have at least one element. */
5361 if (! implicit && pedantic
5362 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5363 ? integer_zerop (constructor_unfilled_index)
5364 : constructor_unfilled_fields == TYPE_FIELDS (constructor_type)))
5365 pedwarn_init ("empty braces in initializer");
5368 /* Pad out the end of the structure. */
5370 if (p->replacement_value)
5371 /* If this closes a superfluous brace pair,
5372 just pass out the element between them. */
5373 constructor = p->replacement_value;
5374 else if (constructor_type == 0)
5376 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5377 && TREE_CODE (constructor_type) != UNION_TYPE
5378 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5380 /* A nonincremental scalar initializer--just return
5381 the element, after verifying there is just one. */
5382 if (constructor_elements == 0)
5384 error_init ("empty scalar initializer");
5385 constructor = error_mark_node;
5387 else if (TREE_CHAIN (constructor_elements) != 0)
5389 error_init ("extra elements in scalar initializer");
5390 constructor = TREE_VALUE (constructor_elements);
5393 constructor = TREE_VALUE (constructor_elements);
5397 if (constructor_erroneous)
5398 constructor = error_mark_node;
5401 constructor = build (CONSTRUCTOR, constructor_type, NULL_TREE,
5402 nreverse (constructor_elements));
5403 if (constructor_constant)
5404 TREE_CONSTANT (constructor) = 1;
5405 if (constructor_constant && constructor_simple)
5406 TREE_STATIC (constructor) = 1;
5410 constructor_type = p->type;
5411 constructor_fields = p->fields;
5412 constructor_index = p->index;
5413 constructor_range_end = p->range_end;
5414 constructor_max_index = p->max_index;
5415 constructor_unfilled_index = p->unfilled_index;
5416 constructor_unfilled_fields = p->unfilled_fields;
5417 constructor_bit_index = p->bit_index;
5418 constructor_elements = p->elements;
5419 constructor_constant = p->constant;
5420 constructor_simple = p->simple;
5421 constructor_erroneous = p->erroneous;
5422 constructor_pending_elts = p->pending_elts;
5423 constructor_depth = p->depth;
5424 RESTORE_SPELLING_DEPTH (constructor_depth);
5426 constructor_stack = p->next;
5429 if (constructor == 0)
5431 if (constructor_stack == 0)
5432 return error_mark_node;
5438 /* Within an array initializer, specify the next index to be initialized.
5439 FIRST is that index. If LAST is nonzero, then initialize a range
5440 of indices, running from FIRST through LAST. */
5443 set_init_index (first, last)
5446 while ((TREE_CODE (first) == NOP_EXPR
5447 || TREE_CODE (first) == CONVERT_EXPR
5448 || TREE_CODE (first) == NON_LVALUE_EXPR)
5449 && (TYPE_MODE (TREE_TYPE (first))
5450 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0)))))
5451 first = TREE_OPERAND (first, 0);
5454 while ((TREE_CODE (last) == NOP_EXPR
5455 || TREE_CODE (last) == CONVERT_EXPR
5456 || TREE_CODE (last) == NON_LVALUE_EXPR)
5457 && (TYPE_MODE (TREE_TYPE (last))
5458 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0)))))
5459 last = TREE_OPERAND (last, 0);
5461 if (TREE_CODE (first) != INTEGER_CST)
5462 error_init ("nonconstant array index in initializer");
5463 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5464 error_init ("nonconstant array index in initializer");
5465 else if (! constructor_unfilled_index)
5466 error_init ("array index in non-array initializer");
5467 else if (tree_int_cst_lt (first, constructor_unfilled_index))
5468 error_init ("duplicate array index in initializer");
5471 constructor_index = convert (bitsizetype, first);
5473 if (last != 0 && tree_int_cst_lt (last, first))
5474 error_init ("empty index range in initializer");
5476 constructor_range_end = last ? convert (bitsizetype, last) : 0;
5480 /* Within a struct initializer, specify the next field to be initialized. */
5483 set_init_label (fieldname)
5489 /* Don't die if an entire brace-pair level is superfluous
5490 in the containing level. */
5491 if (constructor_type == 0)
5494 for (tail = TYPE_FIELDS (constructor_type); tail;
5495 tail = TREE_CHAIN (tail))
5497 if (tail == constructor_unfilled_fields)
5499 if (DECL_NAME (tail) == fieldname)
5504 error ("unknown field `%s' specified in initializer",
5505 IDENTIFIER_POINTER (fieldname));
5507 error ("field `%s' already initialized",
5508 IDENTIFIER_POINTER (fieldname));
5510 constructor_fields = tail;
5513 /* Add a new initializer to the tree of pending initializers. PURPOSE
5514 indentifies the initializer, either array index or field in a structure.
5515 VALUE is the value of that index or field. */
5518 add_pending_init (purpose, value)
5519 tree purpose, value;
5521 struct init_node *p, **q, *r;
5523 q = &constructor_pending_elts;
5526 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5531 if (tree_int_cst_lt (purpose, p->purpose))
5533 else if (p->purpose != purpose)
5544 if (tree_int_cst_lt (bit_position (purpose),
5545 bit_position (p->purpose)))
5547 else if (p->purpose != purpose)
5554 r = (struct init_node *) ggc_alloc (sizeof (struct init_node));
5555 r->purpose = purpose;
5566 struct init_node *s;
5570 if (p->balance == 0)
5572 else if (p->balance < 0)
5579 p->left->parent = p;
5596 constructor_pending_elts = r;
5601 struct init_node *t = r->right;
5605 r->right->parent = r;
5610 p->left->parent = p;
5613 p->balance = t->balance < 0;
5614 r->balance = -(t->balance > 0);
5629 constructor_pending_elts = t;
5635 /* p->balance == +1; growth of left side balances the node. */
5640 else /* r == p->right */
5642 if (p->balance == 0)
5643 /* Growth propagation from right side. */
5645 else if (p->balance > 0)
5652 p->right->parent = p;
5669 constructor_pending_elts = r;
5671 else /* r->balance == -1 */
5674 struct init_node *t = r->left;
5678 r->left->parent = r;
5683 p->right->parent = p;
5686 r->balance = (t->balance < 0);
5687 p->balance = -(t->balance > 0);
5702 constructor_pending_elts = t;
5708 /* p->balance == -1; growth of right side balances the node. */
5719 /* Return nonzero if FIELD is equal to the index of a pending initializer. */
5722 pending_init_member (field)
5725 struct init_node *p;
5727 p = constructor_pending_elts;
5728 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5732 if (field == p->purpose)
5734 else if (tree_int_cst_lt (field, p->purpose))
5744 if (field == p->purpose)
5746 else if (tree_int_cst_lt (bit_position (field),
5747 bit_position (p->purpose)))
5757 /* "Output" the next constructor element.
5758 At top level, really output it to assembler code now.
5759 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5760 TYPE is the data type that the containing data type wants here.
5761 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5763 PENDING if non-nil means output pending elements that belong
5764 right after this element. (PENDING is normally 1;
5765 it is 0 while outputting pending elements, to avoid recursion.) */
5768 output_init_element (value, type, field, pending)
5769 tree value, type, field;
5774 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5775 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5776 && !(TREE_CODE (value) == STRING_CST
5777 && TREE_CODE (type) == ARRAY_TYPE
5778 && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE)
5779 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5780 TYPE_MAIN_VARIANT (type))))
5781 value = default_conversion (value);
5783 if (value == error_mark_node)
5784 constructor_erroneous = 1;
5785 else if (!TREE_CONSTANT (value))
5786 constructor_constant = 0;
5787 else if (initializer_constant_valid_p (value, TREE_TYPE (value)) == 0
5788 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5789 || TREE_CODE (constructor_type) == UNION_TYPE)
5790 && DECL_C_BIT_FIELD (field)
5791 && TREE_CODE (value) != INTEGER_CST))
5792 constructor_simple = 0;
5794 if (require_constant_value && ! TREE_CONSTANT (value))
5796 error_init ("initializer element is not constant");
5797 value = error_mark_node;
5799 else if (require_constant_elements
5800 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
5802 error_init ("initializer element is not computable at load time");
5803 value = error_mark_node;
5806 /* If this element duplicates one on constructor_pending_elts,
5807 print a message and ignore it. Don't do this when we're
5808 processing elements taken off constructor_pending_elts,
5809 because we'd always get spurious errors. */
5812 if (TREE_CODE (constructor_type) == RECORD_TYPE
5813 || TREE_CODE (constructor_type) == UNION_TYPE
5814 || TREE_CODE (constructor_type) == ARRAY_TYPE)
5816 if (pending_init_member (field))
5818 error_init ("duplicate initializer");
5824 /* If this element doesn't come next in sequence,
5825 put it on constructor_pending_elts. */
5826 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5827 && ! tree_int_cst_equal (field, constructor_unfilled_index))
5830 add_pending_init (field,
5831 digest_init (type, value, require_constant_value,
5832 require_constant_elements));
5834 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5835 && field != constructor_unfilled_fields)
5837 /* We do this for records but not for unions. In a union,
5838 no matter which field is specified, it can be initialized
5839 right away since it starts at the beginning of the union. */
5841 add_pending_init (field,
5842 digest_init (type, value, require_constant_value,
5843 require_constant_elements));
5847 /* Otherwise, output this element either to
5848 constructor_elements or to the assembler file. */
5852 if (field && TREE_CODE (field) == INTEGER_CST)
5853 field = copy_node (field);
5854 constructor_elements
5855 = tree_cons (field, digest_init (type, value,
5856 require_constant_value,
5857 require_constant_elements),
5858 constructor_elements);
5861 /* Advance the variable that indicates sequential elements output. */
5862 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5863 constructor_unfilled_index
5864 = size_binop (PLUS_EXPR, constructor_unfilled_index,
5866 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5868 constructor_unfilled_fields
5869 = TREE_CHAIN (constructor_unfilled_fields);
5871 /* Skip any nameless bit fields. */
5872 while (constructor_unfilled_fields != 0
5873 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5874 && DECL_NAME (constructor_unfilled_fields) == 0)
5875 constructor_unfilled_fields =
5876 TREE_CHAIN (constructor_unfilled_fields);
5878 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5879 constructor_unfilled_fields = 0;
5881 /* Now output any pending elements which have become next. */
5883 output_pending_init_elements (0);
5887 /* Output any pending elements which have become next.
5888 As we output elements, constructor_unfilled_{fields,index}
5889 advances, which may cause other elements to become next;
5890 if so, they too are output.
5892 If ALL is 0, we return when there are
5893 no more pending elements to output now.
5895 If ALL is 1, we output space as necessary so that
5896 we can output all the pending elements. */
5899 output_pending_init_elements (all)
5902 struct init_node *elt = constructor_pending_elts;
5907 /* Look thru the whole pending tree.
5908 If we find an element that should be output now,
5909 output it. Otherwise, set NEXT to the element
5910 that comes first among those still pending. */
5915 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5917 if (tree_int_cst_equal (elt->purpose,
5918 constructor_unfilled_index))
5919 output_init_element (elt->value,
5920 TREE_TYPE (constructor_type),
5921 constructor_unfilled_index, 0);
5922 else if (tree_int_cst_lt (constructor_unfilled_index,
5925 /* Advance to the next smaller node. */
5930 /* We have reached the smallest node bigger than the
5931 current unfilled index. Fill the space first. */
5932 next = elt->purpose;
5938 /* Advance to the next bigger node. */
5943 /* We have reached the biggest node in a subtree. Find
5944 the parent of it, which is the next bigger node. */
5945 while (elt->parent && elt->parent->right == elt)
5948 if (elt && tree_int_cst_lt (constructor_unfilled_index,
5951 next = elt->purpose;
5957 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5958 || TREE_CODE (constructor_type) == UNION_TYPE)
5960 /* If the current record is complete we are done. */
5961 if (constructor_unfilled_fields == 0)
5963 if (elt->purpose == constructor_unfilled_fields)
5965 output_init_element (elt->value,
5966 TREE_TYPE (constructor_unfilled_fields),
5967 constructor_unfilled_fields,
5970 else if (tree_int_cst_lt (bit_position (constructor_unfilled_fields),
5971 bit_position (elt->purpose)))
5973 /* Advance to the next smaller node. */
5978 /* We have reached the smallest node bigger than the
5979 current unfilled field. Fill the space first. */
5980 next = elt->purpose;
5986 /* Advance to the next bigger node. */
5991 /* We have reached the biggest node in a subtree. Find
5992 the parent of it, which is the next bigger node. */
5993 while (elt->parent && elt->parent->right == elt)
5998 (bit_position (constructor_unfilled_fields),
5999 bit_position (elt->purpose))))
6001 next = elt->purpose;
6009 /* Ordinarily return, but not if we want to output all
6010 and there are elements left. */
6011 if (! (all && next != 0))
6014 /* If it's not incremental, just skip over the gap, so that after
6015 jumping to retry we will output the next successive element. */
6016 if (TREE_CODE (constructor_type) == RECORD_TYPE
6017 || TREE_CODE (constructor_type) == UNION_TYPE)
6018 constructor_unfilled_fields = next;
6019 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6020 constructor_unfilled_index = next;
6022 /* ELT now points to the node in the pending tree with the next
6023 initializer to output. */
6027 /* Add one non-braced element to the current constructor level.
6028 This adjusts the current position within the constructor's type.
6029 This may also start or terminate implicit levels
6030 to handle a partly-braced initializer.
6032 Once this has found the correct level for the new element,
6033 it calls output_init_element. */
6036 process_init_element (value)
6039 tree orig_value = value;
6040 int string_flag = value != 0 && TREE_CODE (value) == STRING_CST;
6042 /* Handle superfluous braces around string cst as in
6043 char x[] = {"foo"}; */
6046 && TREE_CODE (constructor_type) == ARRAY_TYPE
6047 && TREE_CODE (TREE_TYPE (constructor_type)) == INTEGER_TYPE
6048 && integer_zerop (constructor_unfilled_index))
6050 if (constructor_stack->replacement_value)
6051 error_init ("excess elements in char array initializer");
6052 constructor_stack->replacement_value = value;
6056 if (constructor_stack->replacement_value != 0)
6058 error_init ("excess elements in struct initializer");
6062 /* Ignore elements of a brace group if it is entirely superfluous
6063 and has already been diagnosed. */
6064 if (constructor_type == 0)
6067 /* If we've exhausted any levels that didn't have braces,
6069 while (constructor_stack->implicit)
6071 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6072 || TREE_CODE (constructor_type) == UNION_TYPE)
6073 && constructor_fields == 0)
6074 process_init_element (pop_init_level (1));
6075 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6076 && (constructor_max_index == 0
6077 || tree_int_cst_lt (constructor_max_index,
6078 constructor_index)))
6079 process_init_element (pop_init_level (1));
6086 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6089 enum tree_code fieldcode;
6091 if (constructor_fields == 0)
6093 pedwarn_init ("excess elements in struct initializer");
6097 fieldtype = TREE_TYPE (constructor_fields);
6098 if (fieldtype != error_mark_node)
6099 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6100 fieldcode = TREE_CODE (fieldtype);
6102 /* Accept a string constant to initialize a subarray. */
6104 && fieldcode == ARRAY_TYPE
6105 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6108 /* Otherwise, if we have come to a subaggregate,
6109 and we don't have an element of its type, push into it. */
6110 else if (value != 0 && !constructor_no_implicit
6111 && value != error_mark_node
6112 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6113 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6114 || fieldcode == UNION_TYPE))
6116 push_init_level (1);
6122 push_member_name (constructor_fields);
6123 output_init_element (value, fieldtype, constructor_fields, 1);
6124 RESTORE_SPELLING_DEPTH (constructor_depth);
6127 /* Do the bookkeeping for an element that was
6128 directly output as a constructor. */
6130 /* For a record, keep track of end position of last field. */
6131 constructor_bit_index
6132 = size_binop (PLUS_EXPR,
6133 bit_position (constructor_fields),
6134 DECL_SIZE (constructor_fields));
6136 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6137 /* Skip any nameless bit fields. */
6138 while (constructor_unfilled_fields != 0
6139 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6140 && DECL_NAME (constructor_unfilled_fields) == 0)
6141 constructor_unfilled_fields =
6142 TREE_CHAIN (constructor_unfilled_fields);
6145 constructor_fields = TREE_CHAIN (constructor_fields);
6146 /* Skip any nameless bit fields at the beginning. */
6147 while (constructor_fields != 0
6148 && DECL_C_BIT_FIELD (constructor_fields)
6149 && DECL_NAME (constructor_fields) == 0)
6150 constructor_fields = TREE_CHAIN (constructor_fields);
6153 if (TREE_CODE (constructor_type) == UNION_TYPE)
6156 enum tree_code fieldcode;
6158 if (constructor_fields == 0)
6160 pedwarn_init ("excess elements in union initializer");
6164 fieldtype = TREE_TYPE (constructor_fields);
6165 if (fieldtype != error_mark_node)
6166 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6167 fieldcode = TREE_CODE (fieldtype);
6169 /* Warn that traditional C rejects initialization of unions.
6170 We skip the warning if the value is zero. This is done
6171 under the assumption that the zero initializer in user
6172 code appears conditioned on e.g. __STDC__ to avoid
6173 "missing initializer" warnings and relies on default
6174 initialization to zero in the traditional C case. */
6175 if (warn_traditional && !in_system_header
6176 && !(value && (integer_zerop (value) || real_zerop (value))))
6177 warning ("traditional C rejects initialization of unions");
6179 /* Accept a string constant to initialize a subarray. */
6181 && fieldcode == ARRAY_TYPE
6182 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
6185 /* Otherwise, if we have come to a subaggregate,
6186 and we don't have an element of its type, push into it. */
6187 else if (value != 0 && !constructor_no_implicit
6188 && value != error_mark_node
6189 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
6190 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6191 || fieldcode == UNION_TYPE))
6193 push_init_level (1);
6199 push_member_name (constructor_fields);
6200 output_init_element (value, fieldtype, constructor_fields, 1);
6201 RESTORE_SPELLING_DEPTH (constructor_depth);
6204 /* Do the bookkeeping for an element that was
6205 directly output as a constructor. */
6207 constructor_bit_index = DECL_SIZE (constructor_fields);
6208 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6211 constructor_fields = 0;
6214 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6216 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6217 enum tree_code eltcode = TREE_CODE (elttype);
6219 /* Accept a string constant to initialize a subarray. */
6221 && eltcode == ARRAY_TYPE
6222 && TREE_CODE (TREE_TYPE (elttype)) == INTEGER_TYPE
6225 /* Otherwise, if we have come to a subaggregate,
6226 and we don't have an element of its type, push into it. */
6227 else if (value != 0 && !constructor_no_implicit
6228 && value != error_mark_node
6229 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != elttype
6230 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6231 || eltcode == UNION_TYPE))
6233 push_init_level (1);
6237 if (constructor_max_index != 0
6238 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6239 || integer_all_onesp (constructor_max_index)))
6241 pedwarn_init ("excess elements in array initializer");
6245 /* In the case of [LO .. HI] = VALUE, only evaluate VALUE once. */
6246 if (constructor_range_end)
6248 if (constructor_max_index != 0
6249 && tree_int_cst_lt (constructor_max_index,
6250 constructor_range_end))
6252 pedwarn_init ("excess elements in array initializer");
6253 constructor_range_end = constructor_max_index;
6256 value = save_expr (value);
6259 /* Now output the actual element.
6260 Ordinarily, output once.
6261 If there is a range, repeat it till we advance past the range. */
6266 push_array_bounds (tree_low_cst (constructor_index, 0));
6267 output_init_element (value, elttype, constructor_index, 1);
6268 RESTORE_SPELLING_DEPTH (constructor_depth);
6272 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6275 /* If we are doing the bookkeeping for an element that was
6276 directly output as a constructor, we must update
6277 constructor_unfilled_index. */
6278 constructor_unfilled_index = constructor_index;
6280 while (! (constructor_range_end == 0
6281 || tree_int_cst_lt (constructor_range_end,
6282 constructor_index)));
6287 /* Handle the sole element allowed in a braced initializer
6288 for a scalar variable. */
6289 if (constructor_fields == 0)
6291 pedwarn_init ("excess elements in scalar initializer");
6296 output_init_element (value, constructor_type, NULL_TREE, 1);
6297 constructor_fields = 0;
6302 /* Expand an ASM statement with operands, handling output operands
6303 that are not variables or INDIRECT_REFS by transforming such
6304 cases into cases that expand_asm_operands can handle.
6306 Arguments are same as for expand_asm_operands. */
6309 c_expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line)
6310 tree string, outputs, inputs, clobbers;
6312 const char *filename;
6315 int noutputs = list_length (outputs);
6317 /* o[I] is the place that output number I should be written. */
6318 register tree *o = (tree *) alloca (noutputs * sizeof (tree));
6321 if (TREE_CODE (string) == ADDR_EXPR)
6322 string = TREE_OPERAND (string, 0);
6323 if (last_tree && TREE_CODE (string) != STRING_CST)
6325 error ("asm template is not a string constant");
6329 /* Record the contents of OUTPUTS before it is modified. */
6330 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6332 tree output = TREE_VALUE (tail);
6334 /* We can remove conversions that just change the type, not the mode. */
6335 STRIP_NOPS (output);
6338 /* Allow conversions as LHS here. build_modify_expr as called below
6339 will do the right thing with them. */
6340 while (TREE_CODE (output) == NOP_EXPR
6341 || TREE_CODE (output) == CONVERT_EXPR
6342 || TREE_CODE (output) == FLOAT_EXPR
6343 || TREE_CODE (output) == FIX_TRUNC_EXPR
6344 || TREE_CODE (output) == FIX_FLOOR_EXPR
6345 || TREE_CODE (output) == FIX_ROUND_EXPR
6346 || TREE_CODE (output) == FIX_CEIL_EXPR)
6347 output = TREE_OPERAND (output, 0);
6350 lvalue_or_else (o[i], "invalid lvalue in asm statement");
6353 /* Perform default conversions on array and function inputs. */
6354 /* Don't do this for other types--
6355 it would screw up operands expected to be in memory. */
6356 for (i = 0, tail = inputs; tail; tail = TREE_CHAIN (tail), i++)
6357 if (TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == ARRAY_TYPE
6358 || TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == FUNCTION_TYPE)
6359 TREE_VALUE (tail) = default_conversion (TREE_VALUE (tail));
6363 add_stmt (build_stmt (ASM_STMT,
6364 vol ? ridpointers[(int) RID_VOLATILE] : NULL_TREE,
6365 string, outputs, inputs, clobbers));
6369 /* Generate the ASM_OPERANDS insn;
6370 store into the TREE_VALUEs of OUTPUTS some trees for
6371 where the values were actually stored. */
6372 expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line);
6374 /* Copy all the intermediate outputs into the specified outputs. */
6375 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6377 if (o[i] != TREE_VALUE (tail))
6379 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
6380 NULL_RTX, VOIDmode, EXPAND_NORMAL);
6383 /* Restore the original value so that it's correct the next
6384 time we expand this function. */
6385 TREE_VALUE (tail) = o[i];
6387 /* Detect modification of read-only values.
6388 (Otherwise done by build_modify_expr.) */
6391 tree type = TREE_TYPE (o[i]);
6392 if (TREE_READONLY (o[i])
6393 || TYPE_READONLY (type)
6394 || ((TREE_CODE (type) == RECORD_TYPE
6395 || TREE_CODE (type) == UNION_TYPE)
6396 && C_TYPE_FIELDS_READONLY (type)))
6397 readonly_warning (o[i], "modification by `asm'");
6401 /* Those MODIFY_EXPRs could do autoincrements. */
6405 /* Expand a C `return' statement.
6406 RETVAL is the expression for what to return,
6407 or a null pointer for `return;' with no value. */
6410 c_expand_return (retval)
6413 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6415 if (TREE_THIS_VOLATILE (current_function_decl))
6416 warning ("function declared `noreturn' has a `return' statement");
6420 current_function_returns_null = 1;
6421 if ((warn_return_type || flag_isoc99)
6422 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6423 pedwarn_c99 ("`return' with no value, in function returning non-void");
6425 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6427 current_function_returns_null = 1;
6428 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6429 pedwarn ("`return' with a value, in function returning void");
6433 tree t = convert_for_assignment (valtype, retval, _("return"),
6434 NULL_TREE, NULL_TREE, 0);
6435 tree res = DECL_RESULT (current_function_decl);
6438 if (t == error_mark_node)
6441 inner = t = convert (TREE_TYPE (res), t);
6443 /* Strip any conversions, additions, and subtractions, and see if
6444 we are returning the address of a local variable. Warn if so. */
6447 switch (TREE_CODE (inner))
6449 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6451 inner = TREE_OPERAND (inner, 0);
6455 /* If the second operand of the MINUS_EXPR has a pointer
6456 type (or is converted from it), this may be valid, so
6457 don't give a warning. */
6459 tree op1 = TREE_OPERAND (inner, 1);
6461 while (! POINTER_TYPE_P (TREE_TYPE (op1))
6462 && (TREE_CODE (op1) == NOP_EXPR
6463 || TREE_CODE (op1) == NON_LVALUE_EXPR
6464 || TREE_CODE (op1) == CONVERT_EXPR))
6465 op1 = TREE_OPERAND (op1, 0);
6467 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6470 inner = TREE_OPERAND (inner, 0);
6475 inner = TREE_OPERAND (inner, 0);
6477 while (TREE_CODE_CLASS (TREE_CODE (inner)) == 'r')
6478 inner = TREE_OPERAND (inner, 0);
6480 if (TREE_CODE (inner) == VAR_DECL
6481 && ! DECL_EXTERNAL (inner)
6482 && ! TREE_STATIC (inner)
6483 && DECL_CONTEXT (inner) == current_function_decl)
6484 warning ("function returns address of local variable");
6494 retval = build (MODIFY_EXPR, TREE_TYPE (res), res, t);
6495 current_function_returns_value = 1;
6498 add_stmt (build_return_stmt (retval));
6502 /* The SWITCH_STMT being built. */
6504 /* A splay-tree mapping the low element of a case range to the high
6505 element, or NULL_TREE if there is no high element. Used to
6506 determine whether or not a new case label duplicates an old case
6507 label. We need a tree, rather than simply a hash table, because
6508 of the GNU case range extension. */
6510 /* The next node on the stack. */
6511 struct c_switch *next;
6514 /* A stack of the currently active switch statements. The innermost
6515 switch statement is on the top of the stack. There is no need to
6516 mark the stack for garbage collection because it is only active
6517 during the processing of the body of a function, and we never
6518 collect at that point. */
6520 static struct c_switch *switch_stack;
6522 /* Start a C switch statement, testing expression EXP. Return the new
6529 register enum tree_code code;
6531 struct c_switch *cs;
6533 if (exp != error_mark_node)
6535 code = TREE_CODE (TREE_TYPE (exp));
6536 type = TREE_TYPE (exp);
6538 if (code != INTEGER_TYPE
6539 && code != ENUMERAL_TYPE
6540 && code != ERROR_MARK)
6542 error ("switch quantity not an integer");
6543 exp = integer_zero_node;
6548 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6550 if (warn_traditional && !in_system_header
6551 && (type == long_integer_type_node
6552 || type == long_unsigned_type_node))
6553 warning ("`long' switch expression not converted to `int' in ISO C");
6555 exp = default_conversion (exp);
6556 type = TREE_TYPE (exp);
6557 index = get_unwidened (exp, NULL_TREE);
6558 /* We can't strip a conversion from a signed type to an
6559 unsigned, because if we did, int_fits_type_p would do the
6560 wrong thing when checking case values for being in range,
6561 and it's too hard to do the right thing. */
6562 if (TREE_UNSIGNED (TREE_TYPE (exp))
6563 == TREE_UNSIGNED (TREE_TYPE (index)))
6568 /* Add this new SWITCH_STMT to the stack. */
6569 cs = (struct c_switch *) xmalloc (sizeof (*cs));
6570 cs->switch_stmt = build_stmt (SWITCH_STMT, exp, NULL_TREE, NULL_TREE);
6571 cs->cases = splay_tree_new (case_compare, NULL, NULL);
6572 cs->next = switch_stack;
6575 return add_stmt (switch_stack->switch_stmt);
6578 /* Process a case label. */
6581 do_case (low_value, high_value)
6586 c_add_case_label (switch_stack->cases,
6587 SWITCH_COND (switch_stack->switch_stmt),
6591 error ("case label not within a switch statement");
6593 error ("`default' label not within a switch statement");
6596 /* Finish the switch statement. */
6601 struct c_switch *cs = switch_stack;
6603 RECHAIN_STMTS (cs->switch_stmt, SWITCH_BODY (cs->switch_stmt));
6605 /* Pop the stack. */
6606 switch_stack = switch_stack->next;
6607 splay_tree_delete (cs->cases);