diff options
Diffstat (limited to 'gnu/usr.bin/cc/cc1/c-typeck.c')
-rw-r--r-- | gnu/usr.bin/cc/cc1/c-typeck.c | 6384 |
1 files changed, 6384 insertions, 0 deletions
diff --git a/gnu/usr.bin/cc/cc1/c-typeck.c b/gnu/usr.bin/cc/cc1/c-typeck.c new file mode 100644 index 0000000..d5283c6 --- /dev/null +++ b/gnu/usr.bin/cc/cc1/c-typeck.c @@ -0,0 +1,6384 @@ +/* Build expressions with type checking for C compiler. + Copyright (C) 1987, 88, 91, 92, 93, 1994 Free Software Foundation, Inc. + +This file is part of GNU CC. + +GNU CC is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU CC is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU CC; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + + +/* This file is part of the C front end. + It contains routines to build C expressions given their operands, + including computing the types of the result, C-specific error checks, + and some optimization. + + There are also routines to build RETURN_STMT nodes and CASE_STMT nodes, + and to process initializations in declarations (since they work + like a strange sort of assignment). */ + +#include "config.h" +#include <stdio.h> +#include "tree.h" +#include "c-tree.h" +#include "flags.h" + +/* Nonzero if we've already printed a "missing braces around initializer" + message within this initializer. */ +static int missing_braces_mentioned; + +extern char *index (); +extern char *rindex (); + +static tree quality_type PROTO((tree, tree)); +static int comp_target_types PROTO((tree, tree)); +static int function_types_compatible_p PROTO((tree, tree)); +static int type_lists_compatible_p PROTO((tree, tree)); +static int self_promoting_type_p PROTO((tree)); +static tree decl_constant_value PROTO((tree)); +static tree lookup_field PROTO((tree, tree, tree *)); +static tree convert_arguments PROTO((tree, tree, tree, tree)); +static tree pointer_int_sum PROTO((enum tree_code, tree, tree)); +static tree pointer_diff PROTO((tree, tree)); +static tree unary_complex_lvalue PROTO((enum tree_code, tree)); +static void pedantic_lvalue_warning PROTO((enum tree_code)); +static tree internal_build_compound_expr PROTO((tree, int)); +static tree convert_for_assignment PROTO((tree, tree, char *, tree, + tree, int)); +static void warn_for_assignment PROTO((char *, char *, tree, int)); +static tree valid_compound_expr_initializer PROTO((tree, tree)); +static void push_string PROTO((char *)); +static void push_member_name PROTO((tree)); +static void push_array_bounds PROTO((int)); +static int spelling_length PROTO((void)); +static char *print_spelling PROTO((char *)); +static char *get_spelling PROTO((char *)); +static void warning_init PROTO((char *, char *, + char *)); +static tree digest_init PROTO((tree, tree, int, int)); +static void check_init_type_bitfields PROTO((tree)); +static void output_init_element PROTO((tree, tree, tree, int)); +static void output_pending_init_elements PROTO((int)); + +/* Do `exp = require_complete_type (exp);' to make sure exp + does not have an incomplete type. (That includes void types.) */ + +tree +require_complete_type (value) + tree value; +{ + tree type = TREE_TYPE (value); + + /* First, detect a valid value with a complete type. */ + if (TYPE_SIZE (type) != 0 + && type != void_type_node) + return value; + + incomplete_type_error (value, type); + return error_mark_node; +} + +/* Print an error message for invalid use of an incomplete type. + VALUE is the expression that was used (or 0 if that isn't known) + and TYPE is the type that was invalid. */ + +void +incomplete_type_error (value, type) + tree value; + tree type; +{ + char *errmsg; + + /* Avoid duplicate error message. */ + if (TREE_CODE (type) == ERROR_MARK) + return; + + if (value != 0 && (TREE_CODE (value) == VAR_DECL + || TREE_CODE (value) == PARM_DECL)) + error ("`%s' has an incomplete type", + IDENTIFIER_POINTER (DECL_NAME (value))); + else + { + retry: + /* We must print an error message. Be clever about what it says. */ + + switch (TREE_CODE (type)) + { + case RECORD_TYPE: + errmsg = "invalid use of undefined type `struct %s'"; + break; + + case UNION_TYPE: + errmsg = "invalid use of undefined type `union %s'"; + break; + + case ENUMERAL_TYPE: + errmsg = "invalid use of undefined type `enum %s'"; + break; + + case VOID_TYPE: + error ("invalid use of void expression"); + return; + + case ARRAY_TYPE: + if (TYPE_DOMAIN (type)) + { + type = TREE_TYPE (type); + goto retry; + } + error ("invalid use of array with unspecified bounds"); + return; + + default: + abort (); + } + + if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE) + error (errmsg, IDENTIFIER_POINTER (TYPE_NAME (type))); + else + /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */ + error ("invalid use of incomplete typedef `%s'", + IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)))); + } +} + +/* Return a variant of TYPE which has all the type qualifiers of LIKE + as well as those of TYPE. */ + +static tree +qualify_type (type, like) + tree type, like; +{ + int constflag = TYPE_READONLY (type) || TYPE_READONLY (like); + int volflag = TYPE_VOLATILE (type) || TYPE_VOLATILE (like); + return c_build_type_variant (type, constflag, volflag); +} + +/* Return the common type of two types. + We assume that comptypes has already been done and returned 1; + if that isn't so, this may crash. In particular, we assume that qualifiers + match. + + This is the type for the result of most arithmetic operations + if the operands have the given two types. */ + +tree +common_type (t1, t2) + tree t1, t2; +{ + register enum tree_code code1; + register enum tree_code code2; + tree attributes; + + /* Save time if the two types are the same. */ + + if (t1 == t2) return t1; + + /* If one type is nonsense, use the other. */ + if (t1 == error_mark_node) + return t2; + if (t2 == error_mark_node) + return t1; + + /* Merge the attributes */ + + { register tree a1, a2; + a1 = TYPE_ATTRIBUTES (t1); + a2 = TYPE_ATTRIBUTES (t2); + + /* Either one unset? Take the set one. */ + + if (!(attributes = a1)) + attributes = a2; + + /* One that completely contains the other? Take it. */ + + else if (a2 && !attribute_list_contained (a1, a2)) + if (attribute_list_contained (a2, a1)) + attributes = a2; + else + { + /* Pick the longest list, and hang on the other + list. */ + + if (list_length (a1) < list_length (a2)) + attributes = a2, a2 = a1; + + for (; a2; a2 = TREE_CHAIN (a2)) + if (!value_member (attributes, a2)) + { + a1 = copy_node (a2); + TREE_CHAIN (a1) = attributes; + attributes = a1; + } + } + } + + /* Treat an enum type as the unsigned integer type of the same width. */ + + if (TREE_CODE (t1) == ENUMERAL_TYPE) + t1 = type_for_size (TYPE_PRECISION (t1), 1); + if (TREE_CODE (t2) == ENUMERAL_TYPE) + t2 = type_for_size (TYPE_PRECISION (t2), 1); + + code1 = TREE_CODE (t1); + code2 = TREE_CODE (t2); + + /* If one type is complex, form the common type of the non-complex + components, then make that complex. Use T1 or T2 if it is the + required type. */ + if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE) + { + tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1; + tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2; + tree subtype = common_type (subtype1, subtype2); + + if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype) + return build_type_attribute_variant (t1, attributes); + else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype) + return build_type_attribute_variant (t2, attributes); + else + return build_type_attribute_variant (build_complex_type (subtype), + attributes); + } + + switch (code1) + { + case INTEGER_TYPE: + case REAL_TYPE: + /* If only one is real, use it as the result. */ + + if (code1 == REAL_TYPE && code2 != REAL_TYPE) + return build_type_attribute_variant (t1, attributes); + + if (code2 == REAL_TYPE && code1 != REAL_TYPE) + return build_type_attribute_variant (t2, attributes); + + /* Both real or both integers; use the one with greater precision. */ + + if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2)) + return build_type_attribute_variant (t1, attributes); + else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1)) + return build_type_attribute_variant (t2, attributes); + + /* Same precision. Prefer longs to ints even when same size. */ + + if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node + || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node) + return build_type_attribute_variant (long_unsigned_type_node, + attributes); + + if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node + || TYPE_MAIN_VARIANT (t2) == long_integer_type_node) + { + /* But preserve unsignedness from the other type, + since long cannot hold all the values of an unsigned int. */ + if (TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2)) + t1 = long_unsigned_type_node; + else + t1 = long_integer_type_node; + return build_type_attribute_variant (t1, attributes); + } + + /* Otherwise prefer the unsigned one. */ + + if (TREE_UNSIGNED (t1)) + return build_type_attribute_variant (t1, attributes); + else + return build_type_attribute_variant (t2, attributes); + + case POINTER_TYPE: + /* For two pointers, do this recursively on the target type, + and combine the qualifiers of the two types' targets. */ + /* This code was turned off; I don't know why. + But ANSI C specifies doing this with the qualifiers. + So I turned it on again. */ + { + tree target = common_type (TYPE_MAIN_VARIANT (TREE_TYPE (t1)), + TYPE_MAIN_VARIANT (TREE_TYPE (t2))); + int constp + = TYPE_READONLY (TREE_TYPE (t1)) || TYPE_READONLY (TREE_TYPE (t2)); + int volatilep + = TYPE_VOLATILE (TREE_TYPE (t1)) || TYPE_VOLATILE (TREE_TYPE (t2)); + t1 = build_pointer_type (c_build_type_variant (target, constp, + volatilep)); + return build_type_attribute_variant (t1, attributes); + } +#if 0 + t1 = build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2))); + return build_type_attribute_variant (t1, attributes); +#endif + + case ARRAY_TYPE: + { + tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2)); + /* Save space: see if the result is identical to one of the args. */ + if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1)) + return build_type_attribute_variant (t1, attributes); + if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)) + return build_type_attribute_variant (t2, attributes); + /* Merge the element types, and have a size if either arg has one. */ + t1 = build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2)); + return build_type_attribute_variant (t1, attributes); + } + + case FUNCTION_TYPE: + /* Function types: prefer the one that specified arg types. + If both do, merge the arg types. Also merge the return types. */ + { + tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2)); + tree p1 = TYPE_ARG_TYPES (t1); + tree p2 = TYPE_ARG_TYPES (t2); + int len; + tree newargs, n; + int i; + + /* Save space: see if the result is identical to one of the args. */ + if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2)) + return build_type_attribute_variant (t1, attributes); + if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1)) + return build_type_attribute_variant (t2, attributes); + + /* Simple way if one arg fails to specify argument types. */ + if (TYPE_ARG_TYPES (t1) == 0) + { + t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2)); + return build_type_attribute_variant (t1, attributes); + } + if (TYPE_ARG_TYPES (t2) == 0) + { + t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1)); + return build_type_attribute_variant (t1, attributes); + } + + /* If both args specify argument types, we must merge the two + lists, argument by argument. */ + + len = list_length (p1); + newargs = 0; + + for (i = 0; i < len; i++) + newargs = tree_cons (NULL_TREE, NULL_TREE, newargs); + + n = newargs; + + for (; p1; + p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n)) + { + /* A null type means arg type is not specified. + Take whatever the other function type has. */ + if (TREE_VALUE (p1) == 0) + { + TREE_VALUE (n) = TREE_VALUE (p2); + goto parm_done; + } + if (TREE_VALUE (p2) == 0) + { + TREE_VALUE (n) = TREE_VALUE (p1); + goto parm_done; + } + + /* Given wait (union {union wait *u; int *i} *) + and wait (union wait *), + prefer union wait * as type of parm. */ + if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE + && TREE_VALUE (p1) != TREE_VALUE (p2)) + { + tree memb; + for (memb = TYPE_FIELDS (TREE_VALUE (p1)); + memb; memb = TREE_CHAIN (memb)) + if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2))) + { + TREE_VALUE (n) = TREE_VALUE (p2); + if (pedantic) + pedwarn ("function types not truly compatible in ANSI C"); + goto parm_done; + } + } + if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE + && TREE_VALUE (p2) != TREE_VALUE (p1)) + { + tree memb; + for (memb = TYPE_FIELDS (TREE_VALUE (p2)); + memb; memb = TREE_CHAIN (memb)) + if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1))) + { + TREE_VALUE (n) = TREE_VALUE (p1); + if (pedantic) + pedwarn ("function types not truly compatible in ANSI C"); + goto parm_done; + } + } + TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2)); + parm_done: ; + } + + t1 = build_function_type (valtype, newargs); + /* ... falls through ... */ + } + + default: + return build_type_attribute_variant (t1, attributes); + } + +} + +/* Return 1 if TYPE1 and TYPE2 are compatible types for assignment + or various other operations. Return 2 if they are compatible + but a warning may be needed if you use them together. */ + +int +comptypes (type1, type2) + tree type1, type2; +{ + register tree t1 = type1; + register tree t2 = type2; + int attrval, val; + + /* Suppress errors caused by previously reported errors. */ + + if (t1 == t2 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK) + return 1; + + /* Treat an enum type as the integer type of the same width and + signedness. */ + + if (TREE_CODE (t1) == ENUMERAL_TYPE) + t1 = type_for_size (TYPE_PRECISION (t1), TREE_UNSIGNED (t1)); + if (TREE_CODE (t2) == ENUMERAL_TYPE) + t2 = type_for_size (TYPE_PRECISION (t2), TREE_UNSIGNED (t2)); + + if (t1 == t2) + return 1; + + /* Different classes of types can't be compatible. */ + + if (TREE_CODE (t1) != TREE_CODE (t2)) return 0; + + /* Qualifiers must match. */ + + if (TYPE_READONLY (t1) != TYPE_READONLY (t2)) + return 0; + if (TYPE_VOLATILE (t1) != TYPE_VOLATILE (t2)) + return 0; + + /* Allow for two different type nodes which have essentially the same + definition. Note that we already checked for equality of the type + type qualifiers (just above). */ + + if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2)) + return 1; + +#ifndef COMP_TYPE_ATTRIBUTES +#define COMP_TYPE_ATTRIBUTES(t1,t2) 1 +#endif + + /* 1 if no need for warning yet, 2 if warning cause has been seen. */ + if (! (attrval = COMP_TYPE_ATTRIBUTES (t1, t2))) + return 0; + + /* 1 if no need for warning yet, 2 if warning cause has been seen. */ + val = 0; + + switch (TREE_CODE (t1)) + { + case POINTER_TYPE: + val = (TREE_TYPE (t1) == TREE_TYPE (t2) + ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2))); + break; + + case FUNCTION_TYPE: + val = function_types_compatible_p (t1, t2); + break; + + case ARRAY_TYPE: + { + tree d1 = TYPE_DOMAIN (t1); + tree d2 = TYPE_DOMAIN (t2); + val = 1; + + /* Target types must match incl. qualifiers. */ + if (TREE_TYPE (t1) != TREE_TYPE (t2) + && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2)))) + return 0; + + /* Sizes must match unless one is missing or variable. */ + if (d1 == 0 || d2 == 0 || d1 == d2 + || TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST + || TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST + || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST + || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST) + break; + + if (! ((TREE_INT_CST_LOW (TYPE_MIN_VALUE (d1)) + == TREE_INT_CST_LOW (TYPE_MIN_VALUE (d2))) + && (TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d1)) + == TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d2))) + && (TREE_INT_CST_LOW (TYPE_MAX_VALUE (d1)) + == TREE_INT_CST_LOW (TYPE_MAX_VALUE (d2))) + && (TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d1)) + == TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d2))))) + val = 0; + break; + } + + case RECORD_TYPE: + if (maybe_objc_comptypes (t1, t2, 0) == 1) + val = 1; + break; + } + return attrval == 2 && val == 1 ? 2 : val; +} + +/* Return 1 if TTL and TTR are pointers to types that are equivalent, + ignoring their qualifiers. */ + +static int +comp_target_types (ttl, ttr) + tree ttl, ttr; +{ + int val; + + /* Give maybe_objc_comptypes a crack at letting these types through. */ + if (val = maybe_objc_comptypes (ttl, ttr, 1) >= 0) + return val; + + val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)), + TYPE_MAIN_VARIANT (TREE_TYPE (ttr))); + + if (val == 2 && pedantic) + pedwarn ("types are not quite compatible"); + return val; +} + +/* Subroutines of `comptypes'. */ + +/* Return 1 if two function types F1 and F2 are compatible. + If either type specifies no argument types, + the other must specify a fixed number of self-promoting arg types. + Otherwise, if one type specifies only the number of arguments, + the other must specify that number of self-promoting arg types. + Otherwise, the argument types must match. */ + +static int +function_types_compatible_p (f1, f2) + tree f1, f2; +{ + tree args1, args2; + /* 1 if no need for warning yet, 2 if warning cause has been seen. */ + int val = 1; + int val1; + + if (!(TREE_TYPE (f1) == TREE_TYPE (f2) + || (val = comptypes (TREE_TYPE (f1), TREE_TYPE (f2))))) + return 0; + + args1 = TYPE_ARG_TYPES (f1); + args2 = TYPE_ARG_TYPES (f2); + + /* An unspecified parmlist matches any specified parmlist + whose argument types don't need default promotions. */ + + if (args1 == 0) + { + if (!self_promoting_args_p (args2)) + return 0; + /* If one of these types comes from a non-prototype fn definition, + compare that with the other type's arglist. + If they don't match, ask for a warning (but no error). */ + if (TYPE_ACTUAL_ARG_TYPES (f1) + && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1))) + val = 2; + return val; + } + if (args2 == 0) + { + if (!self_promoting_args_p (args1)) + return 0; + if (TYPE_ACTUAL_ARG_TYPES (f2) + && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2))) + val = 2; + return val; + } + + /* Both types have argument lists: compare them and propagate results. */ + val1 = type_lists_compatible_p (args1, args2); + return val1 != 1 ? val1 : val; +} + +/* Check two lists of types for compatibility, + returning 0 for incompatible, 1 for compatible, + or 2 for compatible with warning. */ + +static int +type_lists_compatible_p (args1, args2) + tree args1, args2; +{ + /* 1 if no need for warning yet, 2 if warning cause has been seen. */ + int val = 1; + int newval = 0; + + while (1) + { + if (args1 == 0 && args2 == 0) + return val; + /* If one list is shorter than the other, + they fail to match. */ + if (args1 == 0 || args2 == 0) + return 0; + /* A null pointer instead of a type + means there is supposed to be an argument + but nothing is specified about what type it has. + So match anything that self-promotes. */ + if (TREE_VALUE (args1) == 0) + { + if (! self_promoting_type_p (TREE_VALUE (args2))) + return 0; + } + else if (TREE_VALUE (args2) == 0) + { + if (! self_promoting_type_p (TREE_VALUE (args1))) + return 0; + } + else if (! (newval = comptypes (TREE_VALUE (args1), TREE_VALUE (args2)))) + { + /* Allow wait (union {union wait *u; int *i} *) + and wait (union wait *) to be compatible. */ + if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE + && TYPE_NAME (TREE_VALUE (args1)) == 0 + && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST + && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)), + TYPE_SIZE (TREE_VALUE (args2)))) + { + tree memb; + for (memb = TYPE_FIELDS (TREE_VALUE (args1)); + memb; memb = TREE_CHAIN (memb)) + if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2))) + break; + if (memb == 0) + return 0; + } + else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE + && TYPE_NAME (TREE_VALUE (args2)) == 0 + && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST + && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)), + TYPE_SIZE (TREE_VALUE (args1)))) + { + tree memb; + for (memb = TYPE_FIELDS (TREE_VALUE (args2)); + memb; memb = TREE_CHAIN (memb)) + if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1))) + break; + if (memb == 0) + return 0; + } + else + return 0; + } + + /* comptypes said ok, but record if it said to warn. */ + if (newval > val) + val = newval; + + args1 = TREE_CHAIN (args1); + args2 = TREE_CHAIN (args2); + } +} + +/* Return 1 if PARMS specifies a fixed number of parameters + and none of their types is affected by default promotions. */ + +int +self_promoting_args_p (parms) + tree parms; +{ + register tree t; + for (t = parms; t; t = TREE_CHAIN (t)) + { + register tree type = TREE_VALUE (t); + + if (TREE_CHAIN (t) == 0 && type != void_type_node) + return 0; + + if (type == 0) + return 0; + + if (TYPE_MAIN_VARIANT (type) == float_type_node) + return 0; + + if (C_PROMOTING_INTEGER_TYPE_P (type)) + return 0; + } + return 1; +} + +/* Return 1 if TYPE is not affected by default promotions. */ + +static int +self_promoting_type_p (type) + tree type; +{ + if (TYPE_MAIN_VARIANT (type) == float_type_node) + return 0; + + if (C_PROMOTING_INTEGER_TYPE_P (type)) + return 0; + + return 1; +} + +/* Return an unsigned type the same as TYPE in other respects. */ + +tree +unsigned_type (type) + tree type; +{ + tree type1 = TYPE_MAIN_VARIANT (type); + if (type1 == signed_char_type_node || type1 == char_type_node) + return unsigned_char_type_node; + if (type1 == integer_type_node) + return unsigned_type_node; + if (type1 == short_integer_type_node) + return short_unsigned_type_node; + if (type1 == long_integer_type_node) + return long_unsigned_type_node; + if (type1 == long_long_integer_type_node) + return long_long_unsigned_type_node; + return type; +} + +/* Return a signed type the same as TYPE in other respects. */ + +tree +signed_type (type) + tree type; +{ + tree type1 = TYPE_MAIN_VARIANT (type); + if (type1 == unsigned_char_type_node || type1 == char_type_node) + return signed_char_type_node; + if (type1 == unsigned_type_node) + return integer_type_node; + if (type1 == short_unsigned_type_node) + return short_integer_type_node; + if (type1 == long_unsigned_type_node) + return long_integer_type_node; + if (type1 == long_long_unsigned_type_node) + return long_long_integer_type_node; + return type; +} + +/* Return a type the same as TYPE except unsigned or + signed according to UNSIGNEDP. */ + +tree +signed_or_unsigned_type (unsignedp, type) + int unsignedp; + tree type; +{ + if (! INTEGRAL_TYPE_P (type)) + return type; + if (TYPE_PRECISION (type) == TYPE_PRECISION (signed_char_type_node)) + return unsignedp ? unsigned_char_type_node : signed_char_type_node; + if (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)) + return unsignedp ? unsigned_type_node : integer_type_node; + if (TYPE_PRECISION (type) == TYPE_PRECISION (short_integer_type_node)) + return unsignedp ? short_unsigned_type_node : short_integer_type_node; + if (TYPE_PRECISION (type) == TYPE_PRECISION (long_integer_type_node)) + return unsignedp ? long_unsigned_type_node : long_integer_type_node; + if (TYPE_PRECISION (type) == TYPE_PRECISION (long_long_integer_type_node)) + return (unsignedp ? long_long_unsigned_type_node + : long_long_integer_type_node); + return type; +} + +/* Compute the value of the `sizeof' operator. */ + +tree +c_sizeof (type) + tree type; +{ + enum tree_code code = TREE_CODE (type); + tree t; + + if (code == FUNCTION_TYPE) + { + if (pedantic || warn_pointer_arith) + pedwarn ("sizeof applied to a function type"); + return size_int (1); + } + if (code == VOID_TYPE) + { + if (pedantic || warn_pointer_arith) + pedwarn ("sizeof applied to a void type"); + return size_int (1); + } + if (code == ERROR_MARK) + return size_int (1); + if (TYPE_SIZE (type) == 0) + { + error ("sizeof applied to an incomplete type"); + return size_int (0); + } + + /* Convert in case a char is more than one unit. */ + t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), + size_int (TYPE_PRECISION (char_type_node))); + /* size_binop does not put the constant in range, so do it now. */ + if (TREE_CODE (t) == INTEGER_CST && force_fit_type (t, 0)) + TREE_CONSTANT_OVERFLOW (t) = TREE_OVERFLOW (t) = 1; + return t; +} + +tree +c_sizeof_nowarn (type) + tree type; +{ + enum tree_code code = TREE_CODE (type); + tree t; + + if (code == FUNCTION_TYPE + || code == VOID_TYPE + || code == ERROR_MARK) + return size_int (1); + if (TYPE_SIZE (type) == 0) + return size_int (0); + + /* Convert in case a char is more than one unit. */ + t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), + size_int (TYPE_PRECISION (char_type_node))); + force_fit_type (t, 0); + return t; +} + +/* Compute the size to increment a pointer by. */ + +tree +c_size_in_bytes (type) + tree type; +{ + enum tree_code code = TREE_CODE (type); + tree t; + + if (code == FUNCTION_TYPE) + return size_int (1); + if (code == VOID_TYPE) + return size_int (1); + if (code == ERROR_MARK) + return size_int (1); + if (TYPE_SIZE (type) == 0) + { + error ("arithmetic on pointer to an incomplete type"); + return size_int (1); + } + + /* Convert in case a char is more than one unit. */ + t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), + size_int (BITS_PER_UNIT)); + force_fit_type (t, 0); + return t; +} + +/* Implement the __alignof keyword: Return the minimum required + alignment of TYPE, measured in bytes. */ + +tree +c_alignof (type) + tree type; +{ + enum tree_code code = TREE_CODE (type); + + if (code == FUNCTION_TYPE) + return size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT); + + if (code == VOID_TYPE || code == ERROR_MARK) + return size_int (1); + + return size_int (TYPE_ALIGN (type) / BITS_PER_UNIT); +} + +/* Implement the __alignof keyword: Return the minimum required + alignment of EXPR, measured in bytes. For VAR_DECL's and + FIELD_DECL's return DECL_ALIGN (which can be set from an + "aligned" __attribute__ specification). */ + +tree +c_alignof_expr (expr) + tree expr; +{ + if (TREE_CODE (expr) == VAR_DECL) + return size_int (DECL_ALIGN (expr) / BITS_PER_UNIT); + + if (TREE_CODE (expr) == COMPONENT_REF + && DECL_BIT_FIELD (TREE_OPERAND (expr, 1))) + { + error ("`__alignof' applied to a bit-field"); + return size_int (1); + } + else if (TREE_CODE (expr) == COMPONENT_REF + && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL) + return size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT); + + if (TREE_CODE (expr) == INDIRECT_REF) + { + tree t = TREE_OPERAND (expr, 0); + tree best = t; + int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t))); + + while (TREE_CODE (t) == NOP_EXPR + && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE) + { + int thisalign; + + t = TREE_OPERAND (t, 0); + thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t))); + if (thisalign > bestalign) + best = t, bestalign = thisalign; + } + return c_alignof (TREE_TYPE (TREE_TYPE (best))); + } + else + return c_alignof (TREE_TYPE (expr)); +} +/* Return either DECL or its known constant value (if it has one). */ + +static tree +decl_constant_value (decl) + tree decl; +{ + if (! TREE_PUBLIC (decl) + /* Don't change a variable array bound or initial value to a constant + in a place where a variable is invalid. */ + && current_function_decl != 0 + && ! pedantic + && ! TREE_THIS_VOLATILE (decl) + && TREE_READONLY (decl) && ! ITERATOR_P (decl) + && DECL_INITIAL (decl) != 0 + && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK + /* This is invalid if initial value is not constant. + If it has either a function call, a memory reference, + or a variable, then re-evaluating it could give different results. */ + && TREE_CONSTANT (DECL_INITIAL (decl)) + /* Check for cases where this is sub-optimal, even though valid. */ + && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR + && DECL_MODE (decl) != BLKmode) + return DECL_INITIAL (decl); + return decl; +} + +/* Perform default promotions for C data used in expressions. + Arrays and functions are converted to pointers; + enumeral types or short or char, to int. + In addition, manifest constants symbols are replaced by their values. */ + +tree +default_conversion (exp) + tree exp; +{ + register tree type = TREE_TYPE (exp); + register enum tree_code code = TREE_CODE (type); + + /* Constants can be used directly unless they're not loadable. */ + if (TREE_CODE (exp) == CONST_DECL) + exp = DECL_INITIAL (exp); + /* Replace a nonvolatile const static variable with its value. */ + else if (optimize && TREE_CODE (exp) == VAR_DECL) + { + exp = decl_constant_value (exp); + type = TREE_TYPE (exp); + } + + /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as + an lvalue. */ + /* Do not use STRIP_NOPS here! It will remove conversions from pointer + to integer and cause infinite recursion. */ + while (TREE_CODE (exp) == NON_LVALUE_EXPR + || (TREE_CODE (exp) == NOP_EXPR + && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp))) + exp = TREE_OPERAND (exp, 0); + + /* Normally convert enums to int, + but convert wide enums to something wider. */ + if (code == ENUMERAL_TYPE) + { + type = type_for_size (MAX (TYPE_PRECISION (type), + TYPE_PRECISION (integer_type_node)), + ((flag_traditional + || TYPE_PRECISION (type) >= TYPE_PRECISION (integer_type_node)) + && TREE_UNSIGNED (type))); + return convert (type, exp); + } + + if (C_PROMOTING_INTEGER_TYPE_P (type)) + { + /* Traditionally, unsignedness is preserved in default promotions. + Also preserve unsignedness if not really getting any wider. */ + if (TREE_UNSIGNED (type) + && (flag_traditional + || TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))) + return convert (unsigned_type_node, exp); + return convert (integer_type_node, exp); + } + if (flag_traditional && !flag_allow_single_precision + && TYPE_MAIN_VARIANT (type) == float_type_node) + return convert (double_type_node, exp); + if (code == VOID_TYPE) + { + error ("void value not ignored as it ought to be"); + return error_mark_node; + } + if (code == FUNCTION_TYPE) + { + return build_unary_op (ADDR_EXPR, exp, 0); + } + if (code == ARRAY_TYPE) + { + register tree adr; + tree restype = TREE_TYPE (type); + tree ptrtype; + int constp = 0; + int volatilep = 0; + + if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r' + || TREE_CODE_CLASS (TREE_CODE (exp)) == 'd') + { + constp = TREE_READONLY (exp); + volatilep = TREE_THIS_VOLATILE (exp); + } + + if (TYPE_READONLY (type) || TYPE_VOLATILE (type) + || constp || volatilep) + restype = c_build_type_variant (restype, + TYPE_READONLY (type) || constp, + TYPE_VOLATILE (type) || volatilep); + + if (TREE_CODE (exp) == INDIRECT_REF) + return convert (TYPE_POINTER_TO (restype), + TREE_OPERAND (exp, 0)); + + if (TREE_CODE (exp) == COMPOUND_EXPR) + { + tree op1 = default_conversion (TREE_OPERAND (exp, 1)); + return build (COMPOUND_EXPR, TREE_TYPE (op1), + TREE_OPERAND (exp, 0), op1); + } + + if (!lvalue_p (exp) + && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp))) + { + error ("invalid use of non-lvalue array"); + return error_mark_node; + } + + ptrtype = build_pointer_type (restype); + + if (TREE_CODE (exp) == VAR_DECL) + { + /* ??? This is not really quite correct + in that the type of the operand of ADDR_EXPR + is not the target type of the type of the ADDR_EXPR itself. + Question is, can this lossage be avoided? */ + adr = build1 (ADDR_EXPR, ptrtype, exp); + if (mark_addressable (exp) == 0) + return error_mark_node; + TREE_CONSTANT (adr) = staticp (exp); + TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */ + return adr; + } + /* This way is better for a COMPONENT_REF since it can + simplify the offset for a component. */ + adr = build_unary_op (ADDR_EXPR, exp, 1); + return convert (ptrtype, adr); + } + return exp; +} + +/* Look up component name in the structure type definition. + + If this component name is found indirectly within an anonymous union, + store in *INDIRECT the component which directly contains + that anonymous union. Otherwise, set *INDIRECT to 0. */ + +static tree +lookup_field (type, component, indirect) + tree type, component; + tree *indirect; +{ + tree field; + + /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers + to the field elements. Use a binary search on this array to quickly + find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC + will always be set for structures which have many elements. */ + + if (TYPE_LANG_SPECIFIC (type)) + { + int bot, top, half; + tree *field_array = &TYPE_LANG_SPECIFIC (type)->elts[0]; + + field = TYPE_FIELDS (type); + bot = 0; + top = TYPE_LANG_SPECIFIC (type)->len; + while (top - bot > 1) + { + HOST_WIDE_INT cmp; + + half = (top - bot + 1) >> 1; + field = field_array[bot+half]; + + if (DECL_NAME (field) == NULL_TREE) + { + /* Step through all anon unions in linear fashion. */ + while (DECL_NAME (field_array[bot]) == NULL_TREE) + { + tree anon, junk; + + field = field_array[bot++]; + anon = lookup_field (TREE_TYPE (field), component, &junk); + if (anon != NULL_TREE) + { + *indirect = field; + return anon; + } + } + + /* Entire record is only anon unions. */ + if (bot > top) + return NULL_TREE; + + /* Restart the binary search, with new lower bound. */ + continue; + } + + cmp = (HOST_WIDE_INT) DECL_NAME (field) - (HOST_WIDE_INT) component; + if (cmp == 0) + break; + if (cmp < 0) + bot += half; + else + top = bot + half; + } + + if (DECL_NAME (field_array[bot]) == component) + field = field_array[bot]; + else if (DECL_NAME (field) != component) + field = 0; + } + else + { + for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) + { + if (DECL_NAME (field) == NULL_TREE) + { + tree junk; + tree anon = lookup_field (TREE_TYPE (field), component, &junk); + if (anon != NULL_TREE) + { + *indirect = field; + return anon; + } + } + + if (DECL_NAME (field) == component) + break; + } + } + + *indirect = NULL_TREE; + return field; +} + +/* Make an expression to refer to the COMPONENT field of + structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */ + +tree +build_component_ref (datum, component) + tree datum, component; +{ + register tree type = TREE_TYPE (datum); + register enum tree_code code = TREE_CODE (type); + register tree field = NULL; + register tree ref; + + /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it + unless we are not to support things not strictly ANSI. */ + switch (TREE_CODE (datum)) + { + case COMPOUND_EXPR: + { + tree value = build_component_ref (TREE_OPERAND (datum, 1), component); + return build (COMPOUND_EXPR, TREE_TYPE (value), + TREE_OPERAND (datum, 0), value); + } + case COND_EXPR: + return build_conditional_expr + (TREE_OPERAND (datum, 0), + build_component_ref (TREE_OPERAND (datum, 1), component), + build_component_ref (TREE_OPERAND (datum, 2), component)); + } + + /* See if there is a field or component with name COMPONENT. */ + + if (code == RECORD_TYPE || code == UNION_TYPE) + { + tree indirect = 0; + + if (TYPE_SIZE (type) == 0) + { + incomplete_type_error (NULL_TREE, type); + return error_mark_node; + } + + field = lookup_field (type, component, &indirect); + + if (!field) + { + error (code == RECORD_TYPE + ? "structure has no member named `%s'" + : "union has no member named `%s'", + IDENTIFIER_POINTER (component)); + return error_mark_node; + } + if (TREE_TYPE (field) == error_mark_node) + return error_mark_node; + + /* If FIELD was found buried within an anonymous union, + make one COMPONENT_REF to get that anonymous union, + then fall thru to make a second COMPONENT_REF to get FIELD. */ + if (indirect != 0) + { + ref = build (COMPONENT_REF, TREE_TYPE (indirect), datum, indirect); + if (TREE_READONLY (datum) || TREE_READONLY (indirect)) + TREE_READONLY (ref) = 1; + if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (indirect)) + TREE_THIS_VOLATILE (ref) = 1; + datum = ref; + } + + ref = build (COMPONENT_REF, TREE_TYPE (field), datum, field); + + if (TREE_READONLY (datum) || TREE_READONLY (field)) + TREE_READONLY (ref) = 1; + if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (field)) + TREE_THIS_VOLATILE (ref) = 1; + + return ref; + } + else if (code != ERROR_MARK) + error ("request for member `%s' in something not a structure or union", + IDENTIFIER_POINTER (component)); + + return error_mark_node; +} + +/* Given an expression PTR for a pointer, return an expression + for the value pointed to. + ERRORSTRING is the name of the operator to appear in error messages. */ + +tree +build_indirect_ref (ptr, errorstring) + tree ptr; + char *errorstring; +{ + register tree pointer = default_conversion (ptr); + register tree type = TREE_TYPE (pointer); + + if (TREE_CODE (type) == POINTER_TYPE) + { + if (TREE_CODE (pointer) == ADDR_EXPR + && !flag_volatile + && (TREE_TYPE (TREE_OPERAND (pointer, 0)) + == TREE_TYPE (type))) + return TREE_OPERAND (pointer, 0); + else + { + tree t = TREE_TYPE (type); + register tree ref = build1 (INDIRECT_REF, + TYPE_MAIN_VARIANT (t), pointer); + + if (TYPE_SIZE (t) == 0 && TREE_CODE (t) != ARRAY_TYPE) + { + error ("dereferencing pointer to incomplete type"); + return error_mark_node; + } + if (TREE_CODE (t) == VOID_TYPE) + warning ("dereferencing `void *' pointer"); + + /* We *must* set TREE_READONLY when dereferencing a pointer to const, + so that we get the proper error message if the result is used + to assign to. Also, &* is supposed to be a no-op. + And ANSI C seems to specify that the type of the result + should be the const type. */ + /* A de-reference of a pointer to const is not a const. It is valid + to change it via some other pointer. */ + TREE_READONLY (ref) = TYPE_READONLY (t); + TREE_SIDE_EFFECTS (ref) + = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer) || flag_volatile; + TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t); + return ref; + } + } + else if (TREE_CODE (pointer) != ERROR_MARK) + error ("invalid type argument of `%s'", errorstring); + return error_mark_node; +} + +/* This handles expressions of the form "a[i]", which denotes + an array reference. + + This is logically equivalent in C to *(a+i), but we may do it differently. + If A is a variable or a member, we generate a primitive ARRAY_REF. + This avoids forcing the array out of registers, and can work on + arrays that are not lvalues (for example, members of structures returned + by functions). */ + +tree +build_array_ref (array, index) + tree array, index; +{ + if (index == 0) + { + error ("subscript missing in array reference"); + return error_mark_node; + } + + if (TREE_TYPE (array) == error_mark_node + || TREE_TYPE (index) == error_mark_node) + return error_mark_node; + + if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE + && TREE_CODE (array) != INDIRECT_REF) + { + tree rval, type; + + /* Subscripting with type char is likely to lose + on a machine where chars are signed. + So warn on any machine, but optionally. + Don't warn for unsigned char since that type is safe. + Don't warn for signed char because anyone who uses that + must have done so deliberately. */ + if (warn_char_subscripts + && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node) + warning ("array subscript has type `char'"); + + /* Apply default promotions *after* noticing character types. */ + index = default_conversion (index); + + /* Require integer *after* promotion, for sake of enums. */ + if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE) + { + error ("array subscript is not an integer"); + return error_mark_node; + } + + /* An array that is indexed by a non-constant + cannot be stored in a register; we must be able to do + address arithmetic on its address. + Likewise an array of elements of variable size. */ + if (TREE_CODE (index) != INTEGER_CST + || (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))) != 0 + && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST)) + { + if (mark_addressable (array) == 0) + return error_mark_node; + } + /* An array that is indexed by a constant value which is not within + the array bounds cannot be stored in a register either; because we + would get a crash in store_bit_field/extract_bit_field when trying + to access a non-existent part of the register. */ + if (TREE_CODE (index) == INTEGER_CST + && TYPE_VALUES (TREE_TYPE (array)) + && ! int_fits_type_p (index, TYPE_VALUES (TREE_TYPE (array)))) + { + if (mark_addressable (array) == 0) + return error_mark_node; + } + + if (pedantic && !lvalue_p (array)) + { + if (DECL_REGISTER (array)) + pedwarn ("ANSI C forbids subscripting `register' array"); + else + pedwarn ("ANSI C forbids subscripting non-lvalue array"); + } + + if (pedantic) + { + tree foo = array; + while (TREE_CODE (foo) == COMPONENT_REF) + foo = TREE_OPERAND (foo, 0); + if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo)) + pedwarn ("ANSI C forbids subscripting non-lvalue array"); + } + + type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array))); + rval = build (ARRAY_REF, type, array, index); + /* Array ref is const/volatile if the array elements are + or if the array is. */ + TREE_READONLY (rval) + |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array))) + | TREE_READONLY (array)); + TREE_SIDE_EFFECTS (rval) + |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) + | TREE_SIDE_EFFECTS (array)); + TREE_THIS_VOLATILE (rval) + |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) + /* This was added by rms on 16 Nov 91. + It fixes vol struct foo *a; a->elts[1] + in an inline function. + Hope it doesn't break something else. */ + | TREE_THIS_VOLATILE (array)); + return require_complete_type (fold (rval)); + } + + { + tree ar = default_conversion (array); + tree ind = default_conversion (index); + + /* Put the integer in IND to simplify error checking. */ + if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE) + { + tree temp = ar; + ar = ind; + ind = temp; + } + + if (ar == error_mark_node) + return ar; + + if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE) + { + error ("subscripted value is neither array nor pointer"); + return error_mark_node; + } + if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE) + { + error ("array subscript is not an integer"); + return error_mark_node; + } + + return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0), + "array indexing"); + } +} + +/* Build a function call to function FUNCTION with parameters PARAMS. + PARAMS is a list--a chain of TREE_LIST nodes--in which the + TREE_VALUE of each node is a parameter-expression. + FUNCTION's data type may be a function type or a pointer-to-function. */ + +tree +build_function_call (function, params) + tree function, params; +{ + register tree fntype, fundecl = 0; + register tree coerced_params; + tree name = NULL_TREE, assembler_name = NULL_TREE; + + /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ + STRIP_TYPE_NOPS (function); + + /* Convert anything with function type to a pointer-to-function. */ + if (TREE_CODE (function) == FUNCTION_DECL) + { + name = DECL_NAME (function); + assembler_name = DECL_ASSEMBLER_NAME (function); + + /* Differs from default_conversion by not setting TREE_ADDRESSABLE + (because calling an inline function does not mean the function + needs to be separately compiled). */ + fntype = build_type_variant (TREE_TYPE (function), + TREE_READONLY (function), + TREE_THIS_VOLATILE (function)); + fundecl = function; + function = build1 (ADDR_EXPR, build_pointer_type (fntype), function); + } + else + function = default_conversion (function); + + fntype = TREE_TYPE (function); + + if (TREE_CODE (fntype) == ERROR_MARK) + return error_mark_node; + + if (!(TREE_CODE (fntype) == POINTER_TYPE + && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)) + { + error ("called object is not a function"); + return error_mark_node; + } + + /* fntype now gets the type of function pointed to. */ + fntype = TREE_TYPE (fntype); + + /* Convert the parameters to the types declared in the + function prototype, or apply default promotions. */ + + coerced_params + = convert_arguments (TYPE_ARG_TYPES (fntype), params, name, fundecl); + + /* Check for errors in format strings. */ + + if (warn_format && (name || assembler_name)) + check_function_format (name, assembler_name, coerced_params); + + /* Recognize certain built-in functions so we can make tree-codes + other than CALL_EXPR. We do this when it enables fold-const.c + to do something useful. */ + + if (TREE_CODE (function) == ADDR_EXPR + && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL + && DECL_BUILT_IN (TREE_OPERAND (function, 0))) + switch (DECL_FUNCTION_CODE (TREE_OPERAND (function, 0))) + { + case BUILT_IN_ABS: + case BUILT_IN_LABS: + case BUILT_IN_FABS: + if (coerced_params == 0) + return integer_zero_node; + return build_unary_op (ABS_EXPR, TREE_VALUE (coerced_params), 0); + } + + { + register tree result + = build (CALL_EXPR, TREE_TYPE (fntype), + function, coerced_params, NULL_TREE); + + TREE_SIDE_EFFECTS (result) = 1; + if (TREE_TYPE (result) == void_type_node) + return result; + return require_complete_type (result); + } +} + +/* Convert the argument expressions in the list VALUES + to the types in the list TYPELIST. The result is a list of converted + argument expressions. + + If TYPELIST is exhausted, or when an element has NULL as its type, + perform the default conversions. + + PARMLIST is the chain of parm decls for the function being called. + It may be 0, if that info is not available. + It is used only for generating error messages. + + NAME is an IDENTIFIER_NODE or 0. It is used only for error messages. + + This is also where warnings about wrong number of args are generated. + + Both VALUES and the returned value are chains of TREE_LIST nodes + with the elements of the list in the TREE_VALUE slots of those nodes. */ + +static tree +convert_arguments (typelist, values, name, fundecl) + tree typelist, values, name, fundecl; +{ + register tree typetail, valtail; + register tree result = NULL; + int parmnum; + + /* Scan the given expressions and types, producing individual + converted arguments and pushing them on RESULT in reverse order. */ + + for (valtail = values, typetail = typelist, parmnum = 0; + valtail; + valtail = TREE_CHAIN (valtail), parmnum++) + { + register tree type = typetail ? TREE_VALUE (typetail) : 0; + register tree val = TREE_VALUE (valtail); + + if (type == void_type_node) + { + if (name) + error ("too many arguments to function `%s'", + IDENTIFIER_POINTER (name)); + else + error ("too many arguments to function"); + break; + } + + /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ + /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0 + to convert automatically to a pointer. */ + if (TREE_CODE (val) == NON_LVALUE_EXPR) + val = TREE_OPERAND (val, 0); + + if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE + || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE) + val = default_conversion (val); + + val = require_complete_type (val); + + if (type != 0) + { + /* Formal parm type is specified by a function prototype. */ + tree parmval; + + if (TYPE_SIZE (type) == 0) + { + error ("type of formal parameter %d is incomplete", parmnum + 1); + parmval = val; + } + else + { +#if 0 /* This turns out not to win--there's no way to write a prototype + for a function whose arg type is a union with no tag. */ + /* Nameless union automatically casts the types it contains. */ + if (TREE_CODE (type) == UNION_TYPE && TYPE_NAME (type) == 0) + { + tree field; + + for (field = TYPE_FIELDS (type); field; + field = TREE_CHAIN (field)) + if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)), + TYPE_MAIN_VARIANT (TREE_TYPE (val)))) + break; + + if (field) + val = build1 (CONVERT_EXPR, type, val); + } +#endif + + /* Optionally warn about conversions that + differ from the default conversions. */ + if (warn_conversion) + { + int formal_prec = TYPE_PRECISION (type); + + if (TREE_CODE (type) != REAL_TYPE + && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) + warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1); + else if (TREE_CODE (type) == REAL_TYPE + && TREE_CODE (TREE_TYPE (val)) != REAL_TYPE) + warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1); + else if (TREE_CODE (type) == REAL_TYPE + && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) + { + /* Warn if any argument is passed as `float', + since without a prototype it would be `double'. */ + if (formal_prec == TYPE_PRECISION (float_type_node)) + warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1); + } + /* Detect integer changing in width or signedness. */ + else if ((TREE_CODE (type) == INTEGER_TYPE + || TREE_CODE (type) == ENUMERAL_TYPE) + && (TREE_CODE (TREE_TYPE (val)) == INTEGER_TYPE + || TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE)) + { + tree would_have_been = default_conversion (val); + tree type1 = TREE_TYPE (would_have_been); + + if (TREE_CODE (type) == ENUMERAL_TYPE + && type == TREE_TYPE (val)) + /* No warning if function asks for enum + and the actual arg is that enum type. */ + ; + else if (formal_prec != TYPE_PRECISION (type1)) + warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1); + else if (TREE_UNSIGNED (type) == TREE_UNSIGNED (type1)) + ; + /* Don't complain if the formal parameter type + is an enum, because we can't tell now whether + the value was an enum--even the same enum. */ + else if (TREE_CODE (type) == ENUMERAL_TYPE) + ; + else if (TREE_CODE (val) == INTEGER_CST + && int_fits_type_p (val, type)) + /* Change in signedness doesn't matter + if a constant value is unaffected. */ + ; + /* Likewise for a constant in a NOP_EXPR. */ + else if (TREE_CODE (val) == NOP_EXPR + && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST + && int_fits_type_p (TREE_OPERAND (val, 0), type)) + ; +#if 0 /* We never get such tree structure here. */ + else if (TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE + && int_fits_type_p (TYPE_MIN_VALUE (TREE_TYPE (val)), type) + && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE (val)), type)) + /* Change in signedness doesn't matter + if an enum value is unaffected. */ + ; +#endif + /* If the value is extended from a narrower + unsigned type, it doesn't matter whether we + pass it as signed or unsigned; the value + certainly is the same either way. */ + else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type) + && TREE_UNSIGNED (TREE_TYPE (val))) + ; + else if (TREE_UNSIGNED (type)) + warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1); + else + warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1); + } + } + + parmval = convert_for_assignment (type, val, + (char *)0, /* arg passing */ + fundecl, name, parmnum + 1); + +#ifdef PROMOTE_PROTOTYPES + if ((TREE_CODE (type) == INTEGER_TYPE + || TREE_CODE (type) == ENUMERAL_TYPE) + && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) + parmval = default_conversion (parmval); +#endif + } + result = tree_cons (NULL_TREE, parmval, result); + } + else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE + && (TYPE_PRECISION (TREE_TYPE (val)) + < TYPE_PRECISION (double_type_node))) + /* Convert `float' to `double'. */ + result = tree_cons (NULL_TREE, convert (double_type_node, val), result); + else + /* Convert `short' and `char' to full-size `int'. */ + result = tree_cons (NULL_TREE, default_conversion (val), result); + + if (typetail) + typetail = TREE_CHAIN (typetail); + } + + if (typetail != 0 && TREE_VALUE (typetail) != void_type_node) + { + if (name) + error ("too few arguments to function `%s'", + IDENTIFIER_POINTER (name)); + else + error ("too few arguments to function"); + } + + return nreverse (result); +} + +/* This is the entry point used by the parser + for binary operators in the input. + In addition to constructing the expression, + we check for operands that were written with other binary operators + in a way that is likely to confuse the user. */ + +tree +parser_build_binary_op (code, arg1, arg2) + enum tree_code code; + tree arg1, arg2; +{ + tree result = build_binary_op (code, arg1, arg2, 1); + + char class; + char class1 = TREE_CODE_CLASS (TREE_CODE (arg1)); + char class2 = TREE_CODE_CLASS (TREE_CODE (arg2)); + enum tree_code code1 = ERROR_MARK; + enum tree_code code2 = ERROR_MARK; + + if (class1 == 'e' || class1 == '1' + || class1 == '2' || class1 == '<') + code1 = C_EXP_ORIGINAL_CODE (arg1); + if (class2 == 'e' || class2 == '1' + || class2 == '2' || class2 == '<') + code2 = C_EXP_ORIGINAL_CODE (arg2); + + /* Check for cases such as x+y<<z which users are likely + to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE + is cleared to prevent these warnings. */ + if (warn_parentheses) + { + if (code == LSHIFT_EXPR || code == RSHIFT_EXPR) + { + if (code1 == PLUS_EXPR || code1 == MINUS_EXPR + || code2 == PLUS_EXPR || code2 == MINUS_EXPR) + warning ("suggest parentheses around + or - inside shift"); + } + + if (code == TRUTH_ORIF_EXPR) + { + if (code1 == TRUTH_ANDIF_EXPR + || code2 == TRUTH_ANDIF_EXPR) + warning ("suggest parentheses around && within ||"); + } + + if (code == BIT_IOR_EXPR) + { + if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR + || code1 == PLUS_EXPR || code1 == MINUS_EXPR + || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR + || code2 == PLUS_EXPR || code2 == MINUS_EXPR) + warning ("suggest parentheses around arithmetic in operand of |"); + } + + if (code == BIT_XOR_EXPR) + { + if (code1 == BIT_AND_EXPR + || code1 == PLUS_EXPR || code1 == MINUS_EXPR + || code2 == BIT_AND_EXPR + || code2 == PLUS_EXPR || code2 == MINUS_EXPR) + warning ("suggest parentheses around arithmetic in operand of ^"); + } + + if (code == BIT_AND_EXPR) + { + if (code1 == PLUS_EXPR || code1 == MINUS_EXPR + || code2 == PLUS_EXPR || code2 == MINUS_EXPR) + warning ("suggest parentheses around + or - in operand of &"); + } + } + + /* Similarly, check for cases like 1<=i<=10 that are probably errors. */ + if (TREE_CODE_CLASS (code) == '<' && extra_warnings + && (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')) + warning ("comparisons like X<=Y<=Z do not have their mathematical meaning"); + + unsigned_conversion_warning (result, arg1); + unsigned_conversion_warning (result, arg2); + overflow_warning (result); + + class = TREE_CODE_CLASS (TREE_CODE (result)); + + /* Record the code that was specified in the source, + for the sake of warnings about confusing nesting. */ + if (class == 'e' || class == '1' + || class == '2' || class == '<') + C_SET_EXP_ORIGINAL_CODE (result, code); + else + { + int flag = TREE_CONSTANT (result); + /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR + so that convert_for_assignment wouldn't strip it. + That way, we got warnings for things like p = (1 - 1). + But it turns out we should not get those warnings. */ + result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result); + C_SET_EXP_ORIGINAL_CODE (result, code); + TREE_CONSTANT (result) = flag; + } + + return result; +} + +/* Build a binary-operation expression without default conversions. + CODE is the kind of expression to build. + This function differs from `build' in several ways: + the data type of the result is computed and recorded in it, + warnings are generated if arg data types are invalid, + special handling for addition and subtraction of pointers is known, + and some optimization is done (operations on narrow ints + are done in the narrower type when that gives the same result). + Constant folding is also done before the result is returned. + + Note that the operands will never have enumeral types, or function + or array types, because either they will have the default conversions + performed or they have both just been converted to some other type in which + the arithmetic is to be done. */ + +tree +build_binary_op (code, orig_op0, orig_op1, convert_p) + enum tree_code code; + tree orig_op0, orig_op1; + int convert_p; +{ + tree type0, type1; + register enum tree_code code0, code1; + tree op0, op1; + + /* Expression code to give to the expression when it is built. + Normally this is CODE, which is what the caller asked for, + but in some special cases we change it. */ + register enum tree_code resultcode = code; + + /* Data type in which the computation is to be performed. + In the simplest cases this is the common type of the arguments. */ + register tree result_type = NULL; + + /* Nonzero means operands have already been type-converted + in whatever way is necessary. + Zero means they need to be converted to RESULT_TYPE. */ + int converted = 0; + + /* Nonzero means after finally constructing the expression + give it this type. Otherwise, give it type RESULT_TYPE. */ + tree final_type = 0; + + /* Nonzero if this is an operation like MIN or MAX which can + safely be computed in short if both args are promoted shorts. + Also implies COMMON. + -1 indicates a bitwise operation; this makes a difference + in the exact conditions for when it is safe to do the operation + in a narrower mode. */ + int shorten = 0; + + /* Nonzero if this is a comparison operation; + if both args are promoted shorts, compare the original shorts. + Also implies COMMON. */ + int short_compare = 0; + + /* Nonzero if this is a right-shift operation, which can be computed on the + original short and then promoted if the operand is a promoted short. */ + int short_shift = 0; + + /* Nonzero means set RESULT_TYPE to the common type of the args. */ + int common = 0; + + if (convert_p) + { + op0 = default_conversion (orig_op0); + op1 = default_conversion (orig_op1); + } + else + { + op0 = orig_op0; + op1 = orig_op1; + } + + type0 = TREE_TYPE (op0); + type1 = TREE_TYPE (op1); + + /* The expression codes of the data types of the arguments tell us + whether the arguments are integers, floating, pointers, etc. */ + code0 = TREE_CODE (type0); + code1 = TREE_CODE (type1); + + /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ + STRIP_TYPE_NOPS (op0); + STRIP_TYPE_NOPS (op1); + + /* If an error was already reported for one of the arguments, + avoid reporting another error. */ + + if (code0 == ERROR_MARK || code1 == ERROR_MARK) + return error_mark_node; + + switch (code) + { + case PLUS_EXPR: + /* Handle the pointer + int case. */ + if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) + return pointer_int_sum (PLUS_EXPR, op0, op1); + else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE) + return pointer_int_sum (PLUS_EXPR, op1, op0); + else + common = 1; + break; + + case MINUS_EXPR: + /* Subtraction of two similar pointers. + We must subtract them as integers, then divide by object size. */ + if (code0 == POINTER_TYPE && code1 == POINTER_TYPE + && comp_target_types (type0, type1)) + return pointer_diff (op0, op1); + /* Handle pointer minus int. Just like pointer plus int. */ + else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) + return pointer_int_sum (MINUS_EXPR, op0, op1); + else + common = 1; + break; + + case MULT_EXPR: + common = 1; + break; + + case TRUNC_DIV_EXPR: + case CEIL_DIV_EXPR: + case FLOOR_DIV_EXPR: + case ROUND_DIV_EXPR: + case EXACT_DIV_EXPR: + if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE + || code0 == COMPLEX_TYPE) + && (code1 == INTEGER_TYPE || code1 == REAL_TYPE + || code1 == COMPLEX_TYPE)) + { + if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)) + resultcode = RDIV_EXPR; + else + { + /* Although it would be tempting to shorten always here, that + loses on some targets, since the modulo instruction is + undefined if the quotient can't be represented in the + computation mode. We shorten only if unsigned or if + dividing by something we know != -1. */ + shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0)) + || (TREE_CODE (op1) == INTEGER_CST + && (TREE_INT_CST_LOW (op1) != -1 + || TREE_INT_CST_HIGH (op1) != -1))); + } + common = 1; + } + break; + + case BIT_AND_EXPR: + case BIT_ANDTC_EXPR: + case BIT_IOR_EXPR: + case BIT_XOR_EXPR: + if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) + shorten = -1; + /* If one operand is a constant, and the other is a short type + that has been converted to an int, + really do the work in the short type and then convert the + result to int. If we are lucky, the constant will be 0 or 1 + in the short type, making the entire operation go away. */ + if (TREE_CODE (op0) == INTEGER_CST + && TREE_CODE (op1) == NOP_EXPR + && TYPE_PRECISION (type1) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0))) + && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0)))) + { + final_type = result_type; + op1 = TREE_OPERAND (op1, 0); + result_type = TREE_TYPE (op1); + } + if (TREE_CODE (op1) == INTEGER_CST + && TREE_CODE (op0) == NOP_EXPR + && TYPE_PRECISION (type0) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0))) + && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0)))) + { + final_type = result_type; + op0 = TREE_OPERAND (op0, 0); + result_type = TREE_TYPE (op0); + } + break; + + case TRUNC_MOD_EXPR: + case FLOOR_MOD_EXPR: + if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) + { + /* Although it would be tempting to shorten always here, that loses + on some targets, since the modulo instruction is undefined if the + quotient can't be represented in the computation mode. We shorten + only if unsigned or if dividing by something we know != -1. */ + shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0)) + || (TREE_CODE (op1) == INTEGER_CST + && (TREE_INT_CST_LOW (op1) != -1 + || TREE_INT_CST_HIGH (op1) != -1))); + common = 1; + } + break; + + case TRUTH_ANDIF_EXPR: + case TRUTH_ORIF_EXPR: + case TRUTH_AND_EXPR: + case TRUTH_OR_EXPR: + case TRUTH_XOR_EXPR: + if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE + || code0 == REAL_TYPE || code0 == COMPLEX_TYPE) + && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE + || code1 == REAL_TYPE || code1 == COMPLEX_TYPE)) + { + /* Result of these operations is always an int, + but that does not mean the operands should be + converted to ints! */ + result_type = integer_type_node; + op0 = truthvalue_conversion (op0); + op1 = truthvalue_conversion (op1); + converted = 1; + } + break; + + /* Shift operations: result has same type as first operand; + always convert second operand to int. + Also set SHORT_SHIFT if shifting rightward. */ + + case RSHIFT_EXPR: + if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) + { + if (TREE_CODE (op1) == INTEGER_CST) + { + if (tree_int_cst_sgn (op1) < 0) + warning ("right shift count is negative"); + else + { + if (TREE_INT_CST_LOW (op1) | TREE_INT_CST_HIGH (op1)) + short_shift = 1; + if (TREE_INT_CST_HIGH (op1) != 0 + || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1) + >= TYPE_PRECISION (type0))) + warning ("right shift count >= width of type"); + } + } + /* Use the type of the value to be shifted. + This is what most traditional C compilers do. */ + result_type = type0; + /* Unless traditional, convert the shift-count to an integer, + regardless of size of value being shifted. */ + if (! flag_traditional) + { + if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) + op1 = convert (integer_type_node, op1); + /* Avoid converting op1 to result_type later. */ + converted = 1; + } + } + break; + + case LSHIFT_EXPR: + if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) + { + if (TREE_CODE (op1) == INTEGER_CST) + { + if (tree_int_cst_sgn (op1) < 0) + warning ("left shift count is negative"); + else if (TREE_INT_CST_HIGH (op1) != 0 + || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1) + >= TYPE_PRECISION (type0))) + warning ("left shift count >= width of type"); + } + /* Use the type of the value to be shifted. + This is what most traditional C compilers do. */ + result_type = type0; + /* Unless traditional, convert the shift-count to an integer, + regardless of size of value being shifted. */ + if (! flag_traditional) + { + if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) + op1 = convert (integer_type_node, op1); + /* Avoid converting op1 to result_type later. */ + converted = 1; + } + } + break; + + case RROTATE_EXPR: + case LROTATE_EXPR: + if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) + { + if (TREE_CODE (op1) == INTEGER_CST) + { + if (tree_int_cst_sgn (op1) < 0) + warning ("shift count is negative"); + else if (TREE_INT_CST_HIGH (op1) != 0 + || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1) + >= TYPE_PRECISION (type0))) + warning ("shift count >= width of type"); + } + /* Use the type of the value to be shifted. + This is what most traditional C compilers do. */ + result_type = type0; + /* Unless traditional, convert the shift-count to an integer, + regardless of size of value being shifted. */ + if (! flag_traditional) + { + if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) + op1 = convert (integer_type_node, op1); + /* Avoid converting op1 to result_type later. */ + converted = 1; + } + } + break; + + case EQ_EXPR: + case NE_EXPR: + /* Result of comparison is always int, + but don't convert the args to int! */ + result_type = integer_type_node; + converted = 1; + if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE + || code0 == COMPLEX_TYPE) + && (code1 == INTEGER_TYPE || code1 == REAL_TYPE + || code1 == COMPLEX_TYPE)) + short_compare = 1; + else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) + { + register tree tt0 = TREE_TYPE (type0); + register tree tt1 = TREE_TYPE (type1); + /* Anything compares with void *. void * compares with anything. + Otherwise, the targets must be compatible + and both must be object or both incomplete. */ + if (comp_target_types (type0, type1)) + ; + else if (TYPE_MAIN_VARIANT (tt0) == void_type_node) + { + /* op0 != orig_op0 detects the case of something + whose value is 0 but which isn't a valid null ptr const. */ + if (pedantic && (!integer_zerop (op0) || op0 != orig_op0) + && TREE_CODE (tt1) == FUNCTION_TYPE) + pedwarn ("ANSI C forbids comparison of `void *' with function pointer"); + } + else if (TYPE_MAIN_VARIANT (tt1) == void_type_node) + { + if (pedantic && (!integer_zerop (op1) || op1 != orig_op1) + && TREE_CODE (tt0) == FUNCTION_TYPE) + pedwarn ("ANSI C forbids comparison of `void *' with function pointer"); + } + else + pedwarn ("comparison of distinct pointer types lacks a cast"); + } + else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST + && integer_zerop (op1)) + op1 = null_pointer_node; + else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST + && integer_zerop (op0)) + op0 = null_pointer_node; + else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) + { + if (! flag_traditional) + pedwarn ("comparison between pointer and integer"); + op1 = convert (TREE_TYPE (op0), op1); + } + else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) + { + if (! flag_traditional) + pedwarn ("comparison between pointer and integer"); + op0 = convert (TREE_TYPE (op1), op0); + } + else + /* If args are not valid, clear out RESULT_TYPE + to cause an error message later. */ + result_type = 0; + break; + + case MAX_EXPR: + case MIN_EXPR: + if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) + && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) + shorten = 1; + else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) + { + if (! comp_target_types (type0, type1)) + pedwarn ("comparison of distinct pointer types lacks a cast"); + else if (pedantic + && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE) + pedwarn ("ANSI C forbids ordered comparisons of pointers to functions"); + result_type = common_type (type0, type1); + } + break; + + case LE_EXPR: + case GE_EXPR: + case LT_EXPR: + case GT_EXPR: + if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) + && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) + short_compare = 1; + else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) + { + if (! comp_target_types (type0, type1)) + pedwarn ("comparison of distinct pointer types lacks a cast"); + else if ((TYPE_SIZE (TREE_TYPE (type0)) != 0) + != (TYPE_SIZE (TREE_TYPE (type1)) != 0)) + pedwarn ("comparison of complete and incomplete pointers"); + else if (pedantic + && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE) + pedwarn ("ANSI C forbids ordered comparisons of pointers to functions"); + result_type = integer_type_node; + } + else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST + && integer_zerop (op1)) + { + result_type = integer_type_node; + op1 = null_pointer_node; + if (pedantic) + pedwarn ("ordered comparison of pointer with integer zero"); + } + else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST + && integer_zerop (op0)) + { + result_type = integer_type_node; + op0 = null_pointer_node; + if (pedantic) + pedwarn ("ordered comparison of pointer with integer zero"); + } + else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) + { + result_type = integer_type_node; + if (! flag_traditional) + pedwarn ("comparison between pointer and integer"); + op1 = convert (TREE_TYPE (op0), op1); + } + else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) + { + result_type = integer_type_node; + if (! flag_traditional) + pedwarn ("comparison between pointer and integer"); + op0 = convert (TREE_TYPE (op1), op0); + } + converted = 1; + break; + } + + if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE) + && + (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE)) + { + int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE); + + if (shorten || common || short_compare) + result_type = common_type (type0, type1); + + /* For certain operations (which identify themselves by shorten != 0) + if both args were extended from the same smaller type, + do the arithmetic in that type and then extend. + + shorten !=0 and !=1 indicates a bitwise operation. + For them, this optimization is safe only if + both args are zero-extended or both are sign-extended. + Otherwise, we might change the result. + Eg, (short)-1 | (unsigned short)-1 is (int)-1 + but calculated in (unsigned short) it would be (unsigned short)-1. */ + + if (shorten && none_complex) + { + int unsigned0, unsigned1; + tree arg0 = get_narrower (op0, &unsigned0); + tree arg1 = get_narrower (op1, &unsigned1); + /* UNS is 1 if the operation to be done is an unsigned one. */ + int uns = TREE_UNSIGNED (result_type); + tree type; + + final_type = result_type; + + /* Handle the case that OP0 (or OP1) does not *contain* a conversion + but it *requires* conversion to FINAL_TYPE. */ + + if ((TYPE_PRECISION (TREE_TYPE (op0)) + == TYPE_PRECISION (TREE_TYPE (arg0))) + && TREE_TYPE (op0) != final_type) + unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0)); + if ((TYPE_PRECISION (TREE_TYPE (op1)) + == TYPE_PRECISION (TREE_TYPE (arg1))) + && TREE_TYPE (op1) != final_type) + unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1)); + + /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */ + + /* For bitwise operations, signedness of nominal type + does not matter. Consider only how operands were extended. */ + if (shorten == -1) + uns = unsigned0; + + /* Note that in all three cases below we refrain from optimizing + an unsigned operation on sign-extended args. + That would not be valid. */ + + /* Both args variable: if both extended in same way + from same width, do it in that width. + Do it unsigned if args were zero-extended. */ + if ((TYPE_PRECISION (TREE_TYPE (arg0)) + < TYPE_PRECISION (result_type)) + && (TYPE_PRECISION (TREE_TYPE (arg1)) + == TYPE_PRECISION (TREE_TYPE (arg0))) + && unsigned0 == unsigned1 + && (unsigned0 || !uns)) + result_type + = signed_or_unsigned_type (unsigned0, + common_type (TREE_TYPE (arg0), TREE_TYPE (arg1))); + else if (TREE_CODE (arg0) == INTEGER_CST + && (unsigned1 || !uns) + && (TYPE_PRECISION (TREE_TYPE (arg1)) + < TYPE_PRECISION (result_type)) + && (type = signed_or_unsigned_type (unsigned1, + TREE_TYPE (arg1)), + int_fits_type_p (arg0, type))) + result_type = type; + else if (TREE_CODE (arg1) == INTEGER_CST + && (unsigned0 || !uns) + && (TYPE_PRECISION (TREE_TYPE (arg0)) + < TYPE_PRECISION (result_type)) + && (type = signed_or_unsigned_type (unsigned0, + TREE_TYPE (arg0)), + int_fits_type_p (arg1, type))) + result_type = type; + } + + /* Shifts can be shortened if shifting right. */ + + if (short_shift) + { + int unsigned_arg; + tree arg0 = get_narrower (op0, &unsigned_arg); + + final_type = result_type; + + if (arg0 == op0 && final_type == TREE_TYPE (op0)) + unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0)); + + if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type) + /* If arg is sign-extended and then unsigned-shifted, + we can simulate this with a signed shift in arg's type + only if the extended result is at least twice as wide + as the arg. Otherwise, the shift could use up all the + ones made by sign-extension and bring in zeros. + We can't optimize that case at all, but in most machines + it never happens because available widths are 2**N. */ + && (!TREE_UNSIGNED (final_type) + || unsigned_arg + || 2 * TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (result_type))) + { + /* Do an unsigned shift if the operand was zero-extended. */ + result_type + = signed_or_unsigned_type (unsigned_arg, + TREE_TYPE (arg0)); + /* Convert value-to-be-shifted to that type. */ + if (TREE_TYPE (op0) != result_type) + op0 = convert (result_type, op0); + converted = 1; + } + } + + /* Comparison operations are shortened too but differently. + They identify themselves by setting short_compare = 1. */ + + if (short_compare) + { + /* Don't write &op0, etc., because that would prevent op0 + from being kept in a register. + Instead, make copies of the our local variables and + pass the copies by reference, then copy them back afterward. */ + tree xop0 = op0, xop1 = op1, xresult_type = result_type; + enum tree_code xresultcode = resultcode; + tree val + = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode); + if (val != 0) + return val; + op0 = xop0, op1 = xop1, result_type = xresult_type; + resultcode = xresultcode; + + if (extra_warnings) + { + tree op0_type = TREE_TYPE (orig_op0); + tree op1_type = TREE_TYPE (orig_op1); + int op0_unsigned = TREE_UNSIGNED (op0_type); + int op1_unsigned = TREE_UNSIGNED (op1_type); + + /* Give warnings for comparisons between signed and unsigned + quantities that will fail. Do not warn if the signed quantity + is an unsuffixed integer literal (or some static constant + expression involving such literals) and it is positive. + Do not warn if the width of the unsigned quantity is less + than that of the signed quantity, since in this case all + values of the unsigned quantity fit in the signed quantity. + Do not warn if the signed type is the same size as the + result_type since sign extension does not cause trouble in + this case. */ + /* Do the checking based on the original operand trees, so that + casts will be considered, but default promotions won't be. */ + if (op0_unsigned != op1_unsigned + && ((op0_unsigned + && TYPE_PRECISION (op0_type) >= TYPE_PRECISION (op1_type) + && TYPE_PRECISION (op0_type) < TYPE_PRECISION (result_type) + && (TREE_CODE (op1) != INTEGER_CST + || (TREE_CODE (op1) == INTEGER_CST + && INT_CST_LT (op1, integer_zero_node)))) + || + (op1_unsigned + && TYPE_PRECISION (op1_type) >= TYPE_PRECISION (op0_type) + && TYPE_PRECISION (op1_type) < TYPE_PRECISION (result_type) + && (TREE_CODE (op0) != INTEGER_CST + || (TREE_CODE (op0) == INTEGER_CST + && INT_CST_LT (op0, integer_zero_node)))))) + warning ("comparison between signed and unsigned"); + } + } + } + + /* At this point, RESULT_TYPE must be nonzero to avoid an error message. + If CONVERTED is zero, both args will be converted to type RESULT_TYPE. + Then the expression will be built. + It will be given type FINAL_TYPE if that is nonzero; + otherwise, it will be given type RESULT_TYPE. */ + + if (!result_type) + { + binary_op_error (code); + return error_mark_node; + } + + if (! converted) + { + if (TREE_TYPE (op0) != result_type) + op0 = convert (result_type, op0); + if (TREE_TYPE (op1) != result_type) + op1 = convert (result_type, op1); + } + + { + register tree result = build (resultcode, result_type, op0, op1); + register tree folded; + + folded = fold (result); + if (folded == result) + TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1); + if (final_type != 0) + return convert (final_type, folded); + return folded; + } +} + +/* Return a tree for the sum or difference (RESULTCODE says which) + of pointer PTROP and integer INTOP. */ + +static tree +pointer_int_sum (resultcode, ptrop, intop) + enum tree_code resultcode; + register tree ptrop, intop; +{ + tree size_exp; + + register tree result; + register tree folded; + + /* The result is a pointer of the same type that is being added. */ + + register tree result_type = TREE_TYPE (ptrop); + + if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE) + { + if (pedantic || warn_pointer_arith) + pedwarn ("pointer of type `void *' used in arithmetic"); + size_exp = integer_one_node; + } + else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE) + { + if (pedantic || warn_pointer_arith) + pedwarn ("pointer to a function used in arithmetic"); + size_exp = integer_one_node; + } + else + size_exp = c_size_in_bytes (TREE_TYPE (result_type)); + + /* If what we are about to multiply by the size of the elements + contains a constant term, apply distributive law + and multiply that constant term separately. + This helps produce common subexpressions. */ + + if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR) + && ! TREE_CONSTANT (intop) + && TREE_CONSTANT (TREE_OPERAND (intop, 1)) + && TREE_CONSTANT (size_exp) + /* If the constant comes from pointer subtraction, + skip this optimization--it would cause an error. */ + && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE) + { + enum tree_code subcode = resultcode; + tree int_type = TREE_TYPE (intop); + if (TREE_CODE (intop) == MINUS_EXPR) + subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR); + /* Convert both subexpression types to the type of intop, + because weird cases involving pointer arithmetic + can result in a sum or difference with different type args. */ + ptrop = build_binary_op (subcode, ptrop, + convert (int_type, TREE_OPERAND (intop, 1)), 1); + intop = convert (int_type, TREE_OPERAND (intop, 0)); + } + + /* Convert the integer argument to a type the same size as a pointer + so the multiply won't overflow spuriously. */ + + if (TYPE_PRECISION (TREE_TYPE (intop)) != POINTER_SIZE) + intop = convert (type_for_size (POINTER_SIZE, 0), intop); + + /* Replace the integer argument with a suitable product by the object size. + Do this multiplication as signed, then convert to the appropriate + pointer type (actually unsigned integral). */ + + intop = convert (result_type, + build_binary_op (MULT_EXPR, intop, + convert (TREE_TYPE (intop), size_exp), 1)); + + /* Create the sum or difference. */ + + result = build (resultcode, result_type, ptrop, intop); + + folded = fold (result); + if (folded == result) + TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop); + return folded; +} + +/* Return a tree for the difference of pointers OP0 and OP1. + The resulting tree has type int. */ + +static tree +pointer_diff (op0, op1) + register tree op0, op1; +{ + register tree result, folded; + tree restype = ptrdiff_type_node; + + tree target_type = TREE_TYPE (TREE_TYPE (op0)); + + if (pedantic || warn_pointer_arith) + { + if (TREE_CODE (target_type) == VOID_TYPE) + pedwarn ("pointer of type `void *' used in subtraction"); + if (TREE_CODE (target_type) == FUNCTION_TYPE) + pedwarn ("pointer to a function used in subtraction"); + } + + /* First do the subtraction as integers; + then drop through to build the divide operator. */ + + op0 = build_binary_op (MINUS_EXPR, convert (restype, op0), + convert (restype, op1), 1); + /* This generates an error if op1 is pointer to incomplete type. */ + if (TYPE_SIZE (TREE_TYPE (TREE_TYPE (op1))) == 0) + error ("arithmetic on pointer to an incomplete type"); + + /* This generates an error if op0 is pointer to incomplete type. */ + op1 = c_size_in_bytes (target_type); + + /* Divide by the size, in easiest possible way. */ + + result = build (EXACT_DIV_EXPR, restype, op0, convert (restype, op1)); + + folded = fold (result); + if (folded == result) + TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1); + return folded; +} + +/* Construct and perhaps optimize a tree representation + for a unary operation. CODE, a tree_code, specifies the operation + and XARG is the operand. NOCONVERT nonzero suppresses + the default promotions (such as from short to int). */ + +tree +build_unary_op (code, xarg, noconvert) + enum tree_code code; + tree xarg; + int noconvert; +{ + /* No default_conversion here. It causes trouble for ADDR_EXPR. */ + register tree arg = xarg; + register tree argtype = 0; + register enum tree_code typecode = TREE_CODE (TREE_TYPE (arg)); + char *errstring = NULL; + tree val; + + if (typecode == ERROR_MARK) + return error_mark_node; + if (typecode == ENUMERAL_TYPE) + typecode = INTEGER_TYPE; + + switch (code) + { + case CONVERT_EXPR: + /* This is used for unary plus, because a CONVERT_EXPR + is enough to prevent anybody from looking inside for + associativity, but won't generate any code. */ + if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE + || typecode == COMPLEX_TYPE)) + errstring = "wrong type argument to unary plus"; + else if (!noconvert) + arg = default_conversion (arg); + break; + + case NEGATE_EXPR: + if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE + || typecode == COMPLEX_TYPE)) + errstring = "wrong type argument to unary minus"; + else if (!noconvert) + arg = default_conversion (arg); + break; + + case BIT_NOT_EXPR: + if (typecode == COMPLEX_TYPE) + { + code = CONJ_EXPR; + if (!noconvert) + arg = default_conversion (arg); + } + else if (typecode != INTEGER_TYPE) + errstring = "wrong type argument to bit-complement"; + else if (!noconvert) + arg = default_conversion (arg); + break; + + case ABS_EXPR: + if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE + || typecode == COMPLEX_TYPE)) + errstring = "wrong type argument to abs"; + else if (!noconvert) + arg = default_conversion (arg); + break; + + case CONJ_EXPR: + /* Conjugating a real value is a no-op, but allow it anyway. */ + if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE + || typecode == COMPLEX_TYPE)) + errstring = "wrong type argument to conjugation"; + else if (!noconvert) + arg = default_conversion (arg); + break; + + case TRUTH_NOT_EXPR: + if (typecode != INTEGER_TYPE + && typecode != REAL_TYPE && typecode != POINTER_TYPE + && typecode != COMPLEX_TYPE + /* These will convert to a pointer. */ + && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE) + { + errstring = "wrong type argument to unary exclamation mark"; + break; + } + arg = truthvalue_conversion (arg); + return invert_truthvalue (arg); + + case NOP_EXPR: + break; + + case REALPART_EXPR: + if (TREE_CODE (arg) == COMPLEX_CST) + return TREE_REALPART (arg); + else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) + return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg)); + else + return arg; + + case IMAGPART_EXPR: + if (TREE_CODE (arg) == COMPLEX_CST) + return TREE_IMAGPART (arg); + else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) + return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg)); + else + return convert (TREE_TYPE (arg), integer_zero_node); + + case PREINCREMENT_EXPR: + case POSTINCREMENT_EXPR: + case PREDECREMENT_EXPR: + case POSTDECREMENT_EXPR: + /* Handle complex lvalues (when permitted) + by reduction to simpler cases. */ + + val = unary_complex_lvalue (code, arg); + if (val != 0) + return val; + + /* Increment or decrement the real part of the value, + and don't change the imaginary part. */ + if (typecode == COMPLEX_TYPE) + { + tree real, imag; + + arg = stabilize_reference (arg); + real = build_unary_op (REALPART_EXPR, arg, 1); + imag = build_unary_op (IMAGPART_EXPR, arg, 1); + return build (COMPLEX_EXPR, TREE_TYPE (arg), + build_unary_op (code, real, 1), imag); + } + + /* Report invalid types. */ + + if (typecode != POINTER_TYPE + && typecode != INTEGER_TYPE && typecode != REAL_TYPE) + { + if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) + errstring ="wrong type argument to increment"; + else + errstring ="wrong type argument to decrement"; + break; + } + + { + register tree inc; + tree result_type = TREE_TYPE (arg); + + arg = get_unwidened (arg, 0); + argtype = TREE_TYPE (arg); + + /* Compute the increment. */ + + if (typecode == POINTER_TYPE) + { + /* If pointer target is an undefined struct, + we just cannot know how to do the arithmetic. */ + if (TYPE_SIZE (TREE_TYPE (result_type)) == 0) + error ("%s of pointer to unknown structure", + ((code == PREINCREMENT_EXPR + || code == POSTINCREMENT_EXPR) + ? "increment" : "decrement")); + else if ((pedantic || warn_pointer_arith) + && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE + || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)) + pedwarn ("wrong type argument to %s", + ((code == PREINCREMENT_EXPR + || code == POSTINCREMENT_EXPR) + ? "increment" : "decrement")); + inc = c_sizeof_nowarn (TREE_TYPE (result_type)); + } + else + inc = integer_one_node; + + inc = convert (argtype, inc); + + /* Handle incrementing a cast-expression. */ + + while (1) + switch (TREE_CODE (arg)) + { + case NOP_EXPR: + case CONVERT_EXPR: + case FLOAT_EXPR: + case FIX_TRUNC_EXPR: + case FIX_FLOOR_EXPR: + case FIX_ROUND_EXPR: + case FIX_CEIL_EXPR: + pedantic_lvalue_warning (CONVERT_EXPR); + /* If the real type has the same machine representation + as the type it is cast to, we can make better output + by adding directly to the inside of the cast. */ + if ((TREE_CODE (TREE_TYPE (arg)) + == TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0)))) + && (TYPE_MODE (TREE_TYPE (arg)) + == TYPE_MODE (TREE_TYPE (TREE_OPERAND (arg, 0))))) + arg = TREE_OPERAND (arg, 0); + else + { + tree incremented, modify, value; + arg = stabilize_reference (arg); + if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR) + value = arg; + else + value = save_expr (arg); + incremented = build (((code == PREINCREMENT_EXPR + || code == POSTINCREMENT_EXPR) + ? PLUS_EXPR : MINUS_EXPR), + argtype, value, inc); + TREE_SIDE_EFFECTS (incremented) = 1; + modify = build_modify_expr (arg, NOP_EXPR, incremented); + value = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value); + TREE_USED (value) = 1; + return value; + } + break; + + default: + goto give_up; + } + give_up: + + /* Complain about anything else that is not a true lvalue. */ + if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR + || code == POSTINCREMENT_EXPR) + ? "increment" : "decrement"))) + return error_mark_node; + + /* Report a read-only lvalue. */ + if (TREE_READONLY (arg)) + readonly_warning (arg, + ((code == PREINCREMENT_EXPR + || code == POSTINCREMENT_EXPR) + ? "increment" : "decrement")); + + val = build (code, TREE_TYPE (arg), arg, inc); + TREE_SIDE_EFFECTS (val) = 1; + val = convert (result_type, val); + if (TREE_CODE (val) != code) + TREE_NO_UNUSED_WARNING (val) = 1; + return val; + } + + case ADDR_EXPR: + /* Note that this operation never does default_conversion + regardless of NOCONVERT. */ + + /* Let &* cancel out to simplify resulting code. */ + if (TREE_CODE (arg) == INDIRECT_REF) + { + /* Don't let this be an lvalue. */ + if (lvalue_p (TREE_OPERAND (arg, 0))) + return non_lvalue (TREE_OPERAND (arg, 0)); + return TREE_OPERAND (arg, 0); + } + + /* For &x[y], return x+y */ + if (TREE_CODE (arg) == ARRAY_REF) + { + if (mark_addressable (TREE_OPERAND (arg, 0)) == 0) + return error_mark_node; + return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0), + TREE_OPERAND (arg, 1), 1); + } + + /* Handle complex lvalues (when permitted) + by reduction to simpler cases. */ + val = unary_complex_lvalue (code, arg); + if (val != 0) + return val; + +#if 0 /* Turned off because inconsistent; + float f; *&(int)f = 3.4 stores in int format + whereas (int)f = 3.4 stores in float format. */ + /* Address of a cast is just a cast of the address + of the operand of the cast. */ + switch (TREE_CODE (arg)) + { + case NOP_EXPR: + case CONVERT_EXPR: + case FLOAT_EXPR: + case FIX_TRUNC_EXPR: + case FIX_FLOOR_EXPR: + case FIX_ROUND_EXPR: + case FIX_CEIL_EXPR: + if (pedantic) + pedwarn ("ANSI C forbids the address of a cast expression"); + return convert (build_pointer_type (TREE_TYPE (arg)), + build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), + 0)); + } +#endif + + /* Allow the address of a constructor if all the elements + are constant. */ + if (TREE_CODE (arg) == CONSTRUCTOR && TREE_CONSTANT (arg)) + ; + /* Anything not already handled and not a true memory reference + is an error. */ + else if (typecode != FUNCTION_TYPE && !lvalue_or_else (arg, "unary `&'")) + return error_mark_node; + + /* Ordinary case; arg is a COMPONENT_REF or a decl. */ + argtype = TREE_TYPE (arg); + /* If the lvalue is const or volatile, + merge that into the type that the address will point to. */ + if (TREE_CODE_CLASS (TREE_CODE (arg)) == 'd' + || TREE_CODE_CLASS (TREE_CODE (arg)) == 'r') + { + if (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)) + argtype = c_build_type_variant (argtype, + TREE_READONLY (arg), + TREE_THIS_VOLATILE (arg)); + } + + argtype = build_pointer_type (argtype); + + if (mark_addressable (arg) == 0) + return error_mark_node; + + { + tree addr; + + if (TREE_CODE (arg) == COMPONENT_REF) + { + tree field = TREE_OPERAND (arg, 1); + + addr = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0); + + if (DECL_BIT_FIELD (field)) + { + error ("attempt to take address of bit-field structure member `%s'", + IDENTIFIER_POINTER (DECL_NAME (field))); + return error_mark_node; + } + + addr = convert (argtype, addr); + + if (! integer_zerop (DECL_FIELD_BITPOS (field))) + { + tree offset + = size_binop (EASY_DIV_EXPR, DECL_FIELD_BITPOS (field), + size_int (BITS_PER_UNIT)); + int flag = TREE_CONSTANT (addr); + addr = fold (build (PLUS_EXPR, argtype, + addr, convert (argtype, offset))); + TREE_CONSTANT (addr) = flag; + } + } + else + addr = build1 (code, argtype, arg); + + /* Address of a static or external variable or + file-scope function counts as a constant. */ + if (staticp (arg) + && ! (TREE_CODE (arg) == FUNCTION_DECL + && DECL_CONTEXT (arg) != 0)) + TREE_CONSTANT (addr) = 1; + return addr; + } + } + + if (!errstring) + { + if (argtype == 0) + argtype = TREE_TYPE (arg); + return fold (build1 (code, argtype, arg)); + } + + error (errstring); + return error_mark_node; +} + +#if 0 +/* If CONVERSIONS is a conversion expression or a nested sequence of such, + convert ARG with the same conversions in the same order + and return the result. */ + +static tree +convert_sequence (conversions, arg) + tree conversions; + tree arg; +{ + switch (TREE_CODE (conversions)) + { + case NOP_EXPR: + case CONVERT_EXPR: + case FLOAT_EXPR: + case FIX_TRUNC_EXPR: + case FIX_FLOOR_EXPR: + case FIX_ROUND_EXPR: + case FIX_CEIL_EXPR: + return convert (TREE_TYPE (conversions), + convert_sequence (TREE_OPERAND (conversions, 0), + arg)); + + default: + return arg; + } +} +#endif /* 0 */ + +/* Return nonzero if REF is an lvalue valid for this language. + Lvalues can be assigned, unless their type has TYPE_READONLY. + Lvalues can have their address taken, unless they have DECL_REGISTER. */ + +int +lvalue_p (ref) + tree ref; +{ + register enum tree_code code = TREE_CODE (ref); + + switch (code) + { + case REALPART_EXPR: + case IMAGPART_EXPR: + case COMPONENT_REF: + return lvalue_p (TREE_OPERAND (ref, 0)); + + case STRING_CST: + return 1; + + case INDIRECT_REF: + case ARRAY_REF: + case VAR_DECL: + case PARM_DECL: + case RESULT_DECL: + case ERROR_MARK: + if (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE + && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE) + return 1; + break; + } + return 0; +} + +/* Return nonzero if REF is an lvalue valid for this language; + otherwise, print an error message and return zero. */ + +int +lvalue_or_else (ref, string) + tree ref; + char *string; +{ + int win = lvalue_p (ref); + if (! win) + error ("invalid lvalue in %s", string); + return win; +} + +/* Apply unary lvalue-demanding operator CODE to the expression ARG + for certain kinds of expressions which are not really lvalues + but which we can accept as lvalues. + + If ARG is not a kind of expression we can handle, return zero. */ + +static tree +unary_complex_lvalue (code, arg) + enum tree_code code; + tree arg; +{ + /* Handle (a, b) used as an "lvalue". */ + if (TREE_CODE (arg) == COMPOUND_EXPR) + { + tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0); + pedantic_lvalue_warning (COMPOUND_EXPR); + return build (COMPOUND_EXPR, TREE_TYPE (real_result), + TREE_OPERAND (arg, 0), real_result); + } + + /* Handle (a ? b : c) used as an "lvalue". */ + if (TREE_CODE (arg) == COND_EXPR) + { + pedantic_lvalue_warning (COND_EXPR); + return (build_conditional_expr + (TREE_OPERAND (arg, 0), + build_unary_op (code, TREE_OPERAND (arg, 1), 0), + build_unary_op (code, TREE_OPERAND (arg, 2), 0))); + } + + return 0; +} + +/* If pedantic, warn about improper lvalue. CODE is either COND_EXPR + COMPOUND_EXPR, or CONVERT_EXPR (for casts). */ + +static void +pedantic_lvalue_warning (code) + enum tree_code code; +{ + if (pedantic) + pedwarn ("ANSI C forbids use of %s expressions as lvalues", + code == COND_EXPR ? "conditional" + : code == COMPOUND_EXPR ? "compound" : "cast"); +} + +/* Warn about storing in something that is `const'. */ + +void +readonly_warning (arg, string) + tree arg; + char *string; +{ + char buf[80]; + strcpy (buf, string); + + /* Forbid assignments to iterators. */ + if (TREE_CODE (arg) == VAR_DECL && ITERATOR_P (arg)) + { + strcat (buf, " of iterator `%s'"); + pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (arg))); + } + + if (TREE_CODE (arg) == COMPONENT_REF) + { + if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0)))) + readonly_warning (TREE_OPERAND (arg, 0), string); + else + { + strcat (buf, " of read-only member `%s'"); + pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1)))); + } + } + else if (TREE_CODE (arg) == VAR_DECL) + { + strcat (buf, " of read-only variable `%s'"); + pedwarn (buf, IDENTIFIER_POINTER (DECL_NAME (arg))); + } + else + { + pedwarn ("%s of read-only location", buf); + } +} + +/* Mark EXP saying that we need to be able to take the + address of it; it should not be allocated in a register. + Value is 1 if successful. */ + +int +mark_addressable (exp) + tree exp; +{ + register tree x = exp; + while (1) + switch (TREE_CODE (x)) + { + case ADDR_EXPR: + case COMPONENT_REF: + case ARRAY_REF: + case REALPART_EXPR: + case IMAGPART_EXPR: + x = TREE_OPERAND (x, 0); + break; + + case CONSTRUCTOR: + TREE_ADDRESSABLE (x) = 1; + return 1; + + case VAR_DECL: + case CONST_DECL: + case PARM_DECL: + case RESULT_DECL: + if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x) + && DECL_NONLOCAL (x)) + { + if (TREE_PUBLIC (x)) + { + error ("global register variable `%s' used in nested function", + IDENTIFIER_POINTER (DECL_NAME (x))); + return 0; + } + pedwarn ("register variable `%s' used in nested function", + IDENTIFIER_POINTER (DECL_NAME (x))); + } + else if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)) + { + if (TREE_PUBLIC (x)) + { + error ("address of global register variable `%s' requested", + IDENTIFIER_POINTER (DECL_NAME (x))); + return 0; + } + pedwarn ("address of register variable `%s' requested", + IDENTIFIER_POINTER (DECL_NAME (x))); + } + put_var_into_stack (x); + + /* drops in */ + case FUNCTION_DECL: + TREE_ADDRESSABLE (x) = 1; +#if 0 /* poplevel deals with this now. */ + if (DECL_CONTEXT (x) == 0) + TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1; +#endif + + default: + return 1; + } +} + +/* Build and return a conditional expression IFEXP ? OP1 : OP2. */ + +tree +build_conditional_expr (ifexp, op1, op2) + tree ifexp, op1, op2; +{ + register tree type1; + register tree type2; + register enum tree_code code1; + register enum tree_code code2; + register tree result_type = NULL; + tree orig_op1 = op1, orig_op2 = op2; + + /* If second operand is omitted, it is the same as the first one; + make sure it is calculated only once. */ + if (op1 == 0) + { + if (pedantic) + pedwarn ("ANSI C forbids omitting the middle term of a ?: expression"); + ifexp = op1 = save_expr (ifexp); + } + + ifexp = truthvalue_conversion (default_conversion (ifexp)); + +#if 0 /* Produces wrong result if within sizeof. */ + /* Don't promote the operands separately if they promote + the same way. Return the unpromoted type and let the combined + value get promoted if necessary. */ + + if (TREE_TYPE (op1) == TREE_TYPE (op2) + && TREE_CODE (TREE_TYPE (op1)) != ARRAY_TYPE + && TREE_CODE (TREE_TYPE (op1)) != ENUMERAL_TYPE + && TREE_CODE (TREE_TYPE (op1)) != FUNCTION_TYPE) + { + if (TREE_CODE (ifexp) == INTEGER_CST) + return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1); + + return fold (build (COND_EXPR, TREE_TYPE (op1), ifexp, op1, op2)); + } +#endif + + /* Promote both alternatives. */ + + if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE) + op1 = default_conversion (op1); + if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE) + op2 = default_conversion (op2); + + if (TREE_CODE (ifexp) == ERROR_MARK + || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK + || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK) + return error_mark_node; + + type1 = TREE_TYPE (op1); + code1 = TREE_CODE (type1); + type2 = TREE_TYPE (op2); + code2 = TREE_CODE (type2); + + /* Quickly detect the usual case where op1 and op2 have the same type + after promotion. */ + if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2)) + { + if (type1 == type2) + result_type = type1; + else + result_type = TYPE_MAIN_VARIANT (type1); + } + else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE) + && (code2 == INTEGER_TYPE || code2 == REAL_TYPE)) + { + result_type = common_type (type1, type2); + } + else if (code1 == VOID_TYPE || code2 == VOID_TYPE) + { + if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE)) + pedwarn ("ANSI C forbids conditional expr with only one void side"); + result_type = void_type_node; + } + else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE) + { + if (comp_target_types (type1, type2)) + result_type = common_type (type1, type2); + else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node + && TREE_CODE (orig_op1) != NOP_EXPR) + result_type = qualify_type (type2, type1); + else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node + && TREE_CODE (orig_op2) != NOP_EXPR) + result_type = qualify_type (type1, type2); + else if (TYPE_MAIN_VARIANT (TREE_TYPE (type1)) == void_type_node) + { + if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE) + pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer"); + result_type = qualify_type (type1, type2); + } + else if (TYPE_MAIN_VARIANT (TREE_TYPE (type2)) == void_type_node) + { + if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE) + pedwarn ("ANSI C forbids conditional expr between `void *' and function pointer"); + result_type = qualify_type (type2, type1); + } + else + { + pedwarn ("pointer type mismatch in conditional expression"); + result_type = build_pointer_type (void_type_node); + } + } + else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE) + { + if (! integer_zerop (op2)) + pedwarn ("pointer/integer type mismatch in conditional expression"); + else + { + op2 = null_pointer_node; +#if 0 /* The spec seems to say this is permitted. */ + if (pedantic && TREE_CODE (type1) == FUNCTION_TYPE) + pedwarn ("ANSI C forbids conditional expr between 0 and function pointer"); +#endif + } + result_type = type1; + } + else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE) + { + if (!integer_zerop (op1)) + pedwarn ("pointer/integer type mismatch in conditional expression"); + else + { + op1 = null_pointer_node; +#if 0 /* The spec seems to say this is permitted. */ + if (pedantic && TREE_CODE (type2) == FUNCTION_TYPE) + pedwarn ("ANSI C forbids conditional expr between 0 and function pointer"); +#endif + } + result_type = type2; + } + + if (!result_type) + { + if (flag_cond_mismatch) + result_type = void_type_node; + else + { + error ("type mismatch in conditional expression"); + return error_mark_node; + } + } + + /* Merge const and volatile flags of the incoming types. */ + result_type + = build_type_variant (result_type, + TREE_READONLY (op1) || TREE_READONLY (op2), + TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2)); + + if (result_type != TREE_TYPE (op1)) + op1 = convert_and_check (result_type, op1); + if (result_type != TREE_TYPE (op2)) + op2 = convert_and_check (result_type, op2); + +#if 0 + if (code1 == RECORD_TYPE || code1 == UNION_TYPE) + { + result_type = TREE_TYPE (op1); + if (TREE_CONSTANT (ifexp)) + return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1); + + if (TYPE_MODE (result_type) == BLKmode) + { + register tree tempvar + = build_decl (VAR_DECL, NULL_TREE, result_type); + register tree xop1 = build_modify_expr (tempvar, op1); + register tree xop2 = build_modify_expr (tempvar, op2); + register tree result = fold (build (COND_EXPR, result_type, + ifexp, xop1, xop2)); + + layout_decl (tempvar, TYPE_ALIGN (result_type)); + /* No way to handle variable-sized objects here. + I fear that the entire handling of BLKmode conditional exprs + needs to be redone. */ + if (TREE_CODE (DECL_SIZE (tempvar)) != INTEGER_CST) + abort (); + DECL_RTL (tempvar) + = assign_stack_local (DECL_MODE (tempvar), + (TREE_INT_CST_LOW (DECL_SIZE (tempvar)) + + BITS_PER_UNIT - 1) + / BITS_PER_UNIT, + 0); + + TREE_SIDE_EFFECTS (result) + = TREE_SIDE_EFFECTS (ifexp) | TREE_SIDE_EFFECTS (op1) + | TREE_SIDE_EFFECTS (op2); + return build (COMPOUND_EXPR, result_type, result, tempvar); + } + } +#endif /* 0 */ + + if (TREE_CODE (ifexp) == INTEGER_CST) + return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1); + + return fold (build (COND_EXPR, result_type, ifexp, op1, op2)); +} + +/* Given a list of expressions, return a compound expression + that performs them all and returns the value of the last of them. */ + +tree +build_compound_expr (list) + tree list; +{ + return internal_build_compound_expr (list, TRUE); +} + +static tree +internal_build_compound_expr (list, first_p) + tree list; + int first_p; +{ + register tree rest; + + if (TREE_CHAIN (list) == 0) + { +#if 0 /* If something inside inhibited lvalueness, we should not override. */ + /* Consider (x, y+0), which is not an lvalue since y+0 is not. */ + + /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ + if (TREE_CODE (list) == NON_LVALUE_EXPR) + list = TREE_OPERAND (list, 0); +#endif + + /* Don't let (0, 0) be null pointer constant. */ + if (!first_p && integer_zerop (TREE_VALUE (list))) + return non_lvalue (TREE_VALUE (list)); + return TREE_VALUE (list); + } + + if (TREE_CHAIN (list) != 0 && TREE_CHAIN (TREE_CHAIN (list)) == 0) + { + /* Convert arrays to pointers when there really is a comma operator. */ + if (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (list)))) == ARRAY_TYPE) + TREE_VALUE (TREE_CHAIN (list)) + = default_conversion (TREE_VALUE (TREE_CHAIN (list))); + } + + rest = internal_build_compound_expr (TREE_CHAIN (list), FALSE); + + /* When pedantic, a compound expression can be neither an lvalue + nor an integer constant expression. */ + if (! TREE_SIDE_EFFECTS (TREE_VALUE (list)) && ! pedantic) + return rest; + + return build (COMPOUND_EXPR, TREE_TYPE (rest), TREE_VALUE (list), rest); +} + +/* Build an expression representing a cast to type TYPE of expression EXPR. */ + +tree +build_c_cast (type, expr) + register tree type; + tree expr; +{ + register tree value = expr; + + if (type == error_mark_node || expr == error_mark_node) + return error_mark_node; + type = TYPE_MAIN_VARIANT (type); + +#if 0 + /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ + if (TREE_CODE (value) == NON_LVALUE_EXPR) + value = TREE_OPERAND (value, 0); +#endif + + if (TREE_CODE (type) == ARRAY_TYPE) + { + error ("cast specifies array type"); + return error_mark_node; + } + + if (TREE_CODE (type) == FUNCTION_TYPE) + { + error ("cast specifies function type"); + return error_mark_node; + } + + if (type == TREE_TYPE (value)) + { + if (pedantic) + { + if (TREE_CODE (type) == RECORD_TYPE + || TREE_CODE (type) == UNION_TYPE) + pedwarn ("ANSI C forbids casting nonscalar to the same type"); + } + } + else if (TREE_CODE (type) == UNION_TYPE) + { + tree field; + if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE + || TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE) + value = default_conversion (value); + + for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) + if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)), + TYPE_MAIN_VARIANT (TREE_TYPE (value)))) + break; + + if (field) + { + char *name; + tree t; + + if (pedantic) + pedwarn ("ANSI C forbids casts to union type"); + if (TYPE_NAME (type) != 0) + { + if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE) + name = IDENTIFIER_POINTER (TYPE_NAME (type)); + else + name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))); + } + else + name = ""; + t = digest_init (type, build (CONSTRUCTOR, type, NULL_TREE, + build_tree_list (field, value)), + 0, 0); + TREE_CONSTANT (t) = TREE_CONSTANT (value); + return t; + } + error ("cast to union type from type not present in union"); + return error_mark_node; + } + else + { + tree otype, ovalue; + + /* If casting to void, avoid the error that would come + from default_conversion in the case of a non-lvalue array. */ + if (type == void_type_node) + return build1 (CONVERT_EXPR, type, value); + + /* Convert functions and arrays to pointers, + but don't convert any other types. */ + if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE + || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE) + value = default_conversion (value); + otype = TREE_TYPE (value); + + /* Optionally warn about potentially worrisome casts. */ + + if (warn_cast_qual + && TREE_CODE (type) == POINTER_TYPE + && TREE_CODE (otype) == POINTER_TYPE) + { + if (TYPE_VOLATILE (TREE_TYPE (otype)) + && ! TYPE_VOLATILE (TREE_TYPE (type))) + pedwarn ("cast discards `volatile' from pointer target type"); + if (TYPE_READONLY (TREE_TYPE (otype)) + && ! TYPE_READONLY (TREE_TYPE (type))) + pedwarn ("cast discards `const' from pointer target type"); + } + + /* Warn about possible alignment problems. */ + if (STRICT_ALIGNMENT && warn_cast_align + && TREE_CODE (type) == POINTER_TYPE + && TREE_CODE (otype) == POINTER_TYPE + && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE + && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE + && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype))) + warning ("cast increases required alignment of target type"); + + if (TREE_CODE (type) == INTEGER_TYPE + && TREE_CODE (otype) == POINTER_TYPE + && TYPE_PRECISION (type) != TYPE_PRECISION (otype) + && !TREE_CONSTANT (value)) + warning ("cast from pointer to integer of different size"); + + if (warn_bad_function_cast + && TREE_CODE (value) == CALL_EXPR + && TREE_CODE (type) != TREE_CODE (otype)) + warning ("cast does not match function type"); + + if (TREE_CODE (type) == POINTER_TYPE + && TREE_CODE (otype) == INTEGER_TYPE + && TYPE_PRECISION (type) != TYPE_PRECISION (otype) +#if 0 + /* Don't warn about converting 0 to pointer, + provided the 0 was explicit--not cast or made by folding. */ + && !(TREE_CODE (value) == INTEGER_CST && integer_zerop (value)) +#endif + /* Don't warn about converting any constant. */ + && !TREE_CONSTANT (value)) + warning ("cast to pointer from integer of different size"); + + ovalue = value; + value = convert (type, value); + + /* Ignore any integer overflow caused by the cast. */ + if (TREE_CODE (value) == INTEGER_CST) + { + TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue); + TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue); + } + } + + /* Pedantically, don't ley (void *) (FOO *) 0 be a null pointer constant. */ + if (pedantic && TREE_CODE (value) == INTEGER_CST + && TREE_CODE (expr) == INTEGER_CST + && TREE_CODE (TREE_TYPE (expr)) != INTEGER_TYPE) + value = non_lvalue (value); + + /* If pedantic, don't let a cast be an lvalue. */ + if (value == expr && pedantic) + value = non_lvalue (value); + + return value; +} + +/* Build an assignment expression of lvalue LHS from value RHS. + MODIFYCODE is the code for a binary operator that we use + to combine the old value of LHS with RHS to get the new value. + Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */ + +tree +build_modify_expr (lhs, modifycode, rhs) + tree lhs, rhs; + enum tree_code modifycode; +{ + register tree result; + tree newrhs; + tree lhstype = TREE_TYPE (lhs); + tree olhstype = lhstype; + + /* Types that aren't fully specified cannot be used in assignments. */ + lhs = require_complete_type (lhs); + + /* Avoid duplicate error messages from operands that had errors. */ + if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK) + return error_mark_node; + + /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ + /* Do not use STRIP_NOPS here. We do not want an enumerator + whose value is 0 to count as a null pointer constant. */ + if (TREE_CODE (rhs) == NON_LVALUE_EXPR) + rhs = TREE_OPERAND (rhs, 0); + + newrhs = rhs; + + /* Handle control structure constructs used as "lvalues". */ + + switch (TREE_CODE (lhs)) + { + /* Handle (a, b) used as an "lvalue". */ + case COMPOUND_EXPR: + pedantic_lvalue_warning (COMPOUND_EXPR); + newrhs = build_modify_expr (TREE_OPERAND (lhs, 1), + modifycode, rhs); + if (TREE_CODE (newrhs) == ERROR_MARK) + return error_mark_node; + return build (COMPOUND_EXPR, lhstype, + TREE_OPERAND (lhs, 0), newrhs); + + /* Handle (a ? b : c) used as an "lvalue". */ + case COND_EXPR: + pedantic_lvalue_warning (COND_EXPR); + rhs = save_expr (rhs); + { + /* Produce (a ? (b = rhs) : (c = rhs)) + except that the RHS goes through a save-expr + so the code to compute it is only emitted once. */ + tree cond + = build_conditional_expr (TREE_OPERAND (lhs, 0), + build_modify_expr (TREE_OPERAND (lhs, 1), + modifycode, rhs), + build_modify_expr (TREE_OPERAND (lhs, 2), + modifycode, rhs)); + if (TREE_CODE (cond) == ERROR_MARK) + return cond; + /* Make sure the code to compute the rhs comes out + before the split. */ + return build (COMPOUND_EXPR, TREE_TYPE (lhs), + /* But cast it to void to avoid an "unused" error. */ + convert (void_type_node, rhs), cond); + } + } + + /* If a binary op has been requested, combine the old LHS value with the RHS + producing the value we should actually store into the LHS. */ + + if (modifycode != NOP_EXPR) + { + lhs = stabilize_reference (lhs); + newrhs = build_binary_op (modifycode, lhs, rhs, 1); + } + + /* Handle a cast used as an "lvalue". + We have already performed any binary operator using the value as cast. + Now convert the result to the cast type of the lhs, + and then true type of the lhs and store it there; + then convert result back to the cast type to be the value + of the assignment. */ + + switch (TREE_CODE (lhs)) + { + case NOP_EXPR: + case CONVERT_EXPR: + case FLOAT_EXPR: + case FIX_TRUNC_EXPR: + case FIX_FLOOR_EXPR: + case FIX_ROUND_EXPR: + case FIX_CEIL_EXPR: + if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE + || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE) + newrhs = default_conversion (newrhs); + { + tree inner_lhs = TREE_OPERAND (lhs, 0); + tree result; + result = build_modify_expr (inner_lhs, NOP_EXPR, + convert (TREE_TYPE (inner_lhs), + convert (lhstype, newrhs))); + if (TREE_CODE (result) == ERROR_MARK) + return result; + pedantic_lvalue_warning (CONVERT_EXPR); + return convert (TREE_TYPE (lhs), result); + } + } + + /* Now we have handled acceptable kinds of LHS that are not truly lvalues. + Reject anything strange now. */ + + if (!lvalue_or_else (lhs, "assignment")) + return error_mark_node; + + /* Warn about storing in something that is `const'. */ + + if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype) + || ((TREE_CODE (lhstype) == RECORD_TYPE + || TREE_CODE (lhstype) == UNION_TYPE) + && C_TYPE_FIELDS_READONLY (lhstype))) + readonly_warning (lhs, "assignment"); + + /* If storing into a structure or union member, + it has probably been given type `int'. + Compute the type that would go with + the actual amount of storage the member occupies. */ + + if (TREE_CODE (lhs) == COMPONENT_REF + && (TREE_CODE (lhstype) == INTEGER_TYPE + || TREE_CODE (lhstype) == REAL_TYPE + || TREE_CODE (lhstype) == ENUMERAL_TYPE)) + lhstype = TREE_TYPE (get_unwidened (lhs, 0)); + + /* If storing in a field that is in actuality a short or narrower than one, + we must store in the field in its actual type. */ + + if (lhstype != TREE_TYPE (lhs)) + { + lhs = copy_node (lhs); + TREE_TYPE (lhs) = lhstype; + } + + /* Convert new value to destination type. */ + + newrhs = convert_for_assignment (lhstype, newrhs, "assignment", + NULL_TREE, NULL_TREE, 0); + if (TREE_CODE (newrhs) == ERROR_MARK) + return error_mark_node; + + result = build (MODIFY_EXPR, lhstype, lhs, newrhs); + TREE_SIDE_EFFECTS (result) = 1; + + /* If we got the LHS in a different type for storing in, + convert the result back to the nominal type of LHS + so that the value we return always has the same type + as the LHS argument. */ + + if (olhstype == TREE_TYPE (result)) + return result; + return convert_for_assignment (olhstype, result, "assignment", + NULL_TREE, NULL_TREE, 0); +} + +/* Convert value RHS to type TYPE as preparation for an assignment + to an lvalue of type TYPE. + The real work of conversion is done by `convert'. + The purpose of this function is to generate error messages + for assignments that are not allowed in C. + ERRTYPE is a string to use in error messages: + "assignment", "return", etc. If it is null, this is parameter passing + for a function call (and different error messages are output). Otherwise, + it may be a name stored in the spelling stack and interpreted by + get_spelling. + + FUNNAME is the name of the function being called, + as an IDENTIFIER_NODE, or null. + PARMNUM is the number of the argument, for printing in error messages. */ + +static tree +convert_for_assignment (type, rhs, errtype, fundecl, funname, parmnum) + tree type, rhs; + char *errtype; + tree fundecl, funname; + int parmnum; +{ + register enum tree_code codel = TREE_CODE (type); + register tree rhstype; + register enum tree_code coder; + + /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ + /* Do not use STRIP_NOPS here. We do not want an enumerator + whose value is 0 to count as a null pointer constant. */ + if (TREE_CODE (rhs) == NON_LVALUE_EXPR) + rhs = TREE_OPERAND (rhs, 0); + + if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE + || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE) + rhs = default_conversion (rhs); + else if (optimize && TREE_CODE (rhs) == VAR_DECL) + rhs = decl_constant_value (rhs); + + rhstype = TREE_TYPE (rhs); + coder = TREE_CODE (rhstype); + + if (coder == ERROR_MARK) + return error_mark_node; + + if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype)) + { + overflow_warning (rhs); + /* Check for Objective-C protocols. This will issue a warning if + there are protocol violations. No need to use the return value. */ + maybe_objc_comptypes (type, rhstype, 0); + return rhs; + } + + if (coder == VOID_TYPE) + { + error ("void value not ignored as it ought to be"); + return error_mark_node; + } + /* Arithmetic types all interconvert, and enum is treated like int. */ + if ((codel == INTEGER_TYPE || codel == REAL_TYPE || codel == ENUMERAL_TYPE + || codel == COMPLEX_TYPE) + && + (coder == INTEGER_TYPE || coder == REAL_TYPE || coder == ENUMERAL_TYPE + || coder == COMPLEX_TYPE)) + return convert_and_check (type, rhs); + /* Conversion to a union from its member types. */ + else if (codel == UNION_TYPE) + { + tree memb_types; + for (memb_types = TYPE_FIELDS (type); memb_types; + memb_types = TREE_CHAIN (memb_types)) + { + if (comptypes (TREE_TYPE (memb_types), TREE_TYPE (rhs))) + { + if (pedantic + && !(fundecl != 0 && DECL_IN_SYSTEM_HEADER (fundecl))) + pedwarn ("ANSI C prohibits argument conversion to union type"); + return build1 (NOP_EXPR, type, rhs); + } + else if (coder == POINTER_TYPE + && TREE_CODE (TREE_TYPE (memb_types)) == POINTER_TYPE) + { + tree memb_type = TREE_TYPE (memb_types); + register tree ttl = TREE_TYPE (memb_type); + register tree ttr = TREE_TYPE (rhstype); + + /* Any non-function converts to a [const][volatile] void * + and vice versa; otherwise, targets must be the same. + Meanwhile, the lhs target must have all the qualifiers of the rhs. */ + if (TYPE_MAIN_VARIANT (ttl) == void_type_node + || TYPE_MAIN_VARIANT (ttr) == void_type_node + || comp_target_types (memb_type, rhstype)) + { + /* Const and volatile mean something different for function types, + so the usual warnings are not appropriate. */ + if (TREE_CODE (ttr) != FUNCTION_TYPE + || TREE_CODE (ttl) != FUNCTION_TYPE) + { + if (! TYPE_READONLY (ttl) && TYPE_READONLY (ttr)) + warn_for_assignment ("%s discards `const' from pointer target type", + get_spelling (errtype), funname, parmnum); + if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr)) + warn_for_assignment ("%s discards `volatile' from pointer target type", + get_spelling (errtype), funname, parmnum); + } + else + { + /* Because const and volatile on functions are restrictions + that say the function will not do certain things, + it is okay to use a const or volatile function + where an ordinary one is wanted, but not vice-versa. */ + if (TYPE_READONLY (ttl) && ! TYPE_READONLY (ttr)) + warn_for_assignment ("%s makes `const *' function pointer from non-const", + get_spelling (errtype), funname, parmnum); + if (TYPE_VOLATILE (ttl) && ! TYPE_VOLATILE (ttr)) + warn_for_assignment ("%s makes `volatile *' function pointer from non-volatile", + get_spelling (errtype), funname, parmnum); + } + if (pedantic + && !(fundecl != 0 && DECL_IN_SYSTEM_HEADER (fundecl))) + pedwarn ("ANSI C prohibits argument conversion to union type"); + return build1 (NOP_EXPR, type, rhs); + } + } + } + } + /* Conversions among pointers */ + else if (codel == POINTER_TYPE && coder == POINTER_TYPE) + { + register tree ttl = TREE_TYPE (type); + register tree ttr = TREE_TYPE (rhstype); + + /* Any non-function converts to a [const][volatile] void * + and vice versa; otherwise, targets must be the same. + Meanwhile, the lhs target must have all the qualifiers of the rhs. */ + if (TYPE_MAIN_VARIANT (ttl) == void_type_node + || TYPE_MAIN_VARIANT (ttr) == void_type_node + || comp_target_types (type, rhstype) + || (unsigned_type (TYPE_MAIN_VARIANT (ttl)) + == unsigned_type (TYPE_MAIN_VARIANT (ttr)))) + { + if (pedantic + && ((TYPE_MAIN_VARIANT (ttl) == void_type_node + && TREE_CODE (ttr) == FUNCTION_TYPE) + || + (TYPE_MAIN_VARIANT (ttr) == void_type_node + /* Check TREE_CODE to catch cases like (void *) (char *) 0 + which are not ANSI null ptr constants. */ + && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR) + && TREE_CODE (ttl) == FUNCTION_TYPE))) + warn_for_assignment ("ANSI forbids %s between function pointer and `void *'", + get_spelling (errtype), funname, parmnum); + /* Const and volatile mean something different for function types, + so the usual warnings are not appropriate. */ + else if (TREE_CODE (ttr) != FUNCTION_TYPE + || TREE_CODE (ttl) != FUNCTION_TYPE) + { + if (! TYPE_READONLY (ttl) && TYPE_READONLY (ttr)) + warn_for_assignment ("%s discards `const' from pointer target type", + get_spelling (errtype), funname, parmnum); + else if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr)) + warn_for_assignment ("%s discards `volatile' from pointer target type", + get_spelling (errtype), funname, parmnum); + /* If this is not a case of ignoring a mismatch in signedness, + no warning. */ + else if (TYPE_MAIN_VARIANT (ttl) == void_type_node + || TYPE_MAIN_VARIANT (ttr) == void_type_node + || comp_target_types (type, rhstype)) + ; + /* If there is a mismatch, do warn. */ + else if (pedantic) + warn_for_assignment ("pointer targets in %s differ in signedness", + get_spelling (errtype), funname, parmnum); + } + else + { + /* Because const and volatile on functions are restrictions + that say the function will not do certain things, + it is okay to use a const or volatile function + where an ordinary one is wanted, but not vice-versa. */ + if (TYPE_READONLY (ttl) && ! TYPE_READONLY (ttr)) + warn_for_assignment ("%s makes `const *' function pointer from non-const", + get_spelling (errtype), funname, parmnum); + if (TYPE_VOLATILE (ttl) && ! TYPE_VOLATILE (ttr)) + warn_for_assignment ("%s makes `volatile *' function pointer from non-volatile", + get_spelling (errtype), funname, parmnum); + } + } + else + warn_for_assignment ("%s from incompatible pointer type", + get_spelling (errtype), funname, parmnum); + return convert (type, rhs); + } + else if (codel == POINTER_TYPE && coder == INTEGER_TYPE) + { + /* An explicit constant 0 can convert to a pointer, + or one that results from arithmetic, even including + a cast to integer type. */ + if (! (TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs)) + && + ! (TREE_CODE (rhs) == NOP_EXPR + && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE + && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST + && integer_zerop (TREE_OPERAND (rhs, 0)))) + { + warn_for_assignment ("%s makes pointer from integer without a cast", + get_spelling (errtype), funname, parmnum); + return convert (type, rhs); + } + return null_pointer_node; + } + else if (codel == INTEGER_TYPE && coder == POINTER_TYPE) + { + warn_for_assignment ("%s makes integer from pointer without a cast", + get_spelling (errtype), funname, parmnum); + return convert (type, rhs); + } + + if (!errtype) + { + if (funname) + { + tree selector = maybe_building_objc_message_expr (); + + if (selector && parmnum > 2) + error ("incompatible type for argument %d of `%s'", + parmnum - 2, IDENTIFIER_POINTER (selector)); + else + error ("incompatible type for argument %d of `%s'", + parmnum, IDENTIFIER_POINTER (funname)); + } + else + error ("incompatible type for argument %d of indirect function call", + parmnum); + } + else + error ("incompatible types in %s", get_spelling (errtype)); + + return error_mark_node; +} + +/* Print a warning using MSG. + It gets OPNAME as its one parameter. + If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'". + FUNCTION and ARGNUM are handled specially if we are building an + Objective-C selector. */ + +static void +warn_for_assignment (msg, opname, function, argnum) + char *msg; + char *opname; + tree function; + int argnum; +{ + static char argstring[] = "passing arg %d of `%s'"; + static char argnofun[] = "passing arg %d"; + + if (opname == 0) + { + tree selector = maybe_building_objc_message_expr (); + + if (selector && argnum > 2) + { + function = selector; + argnum -= 2; + } + if (function) + { + /* Function name is known; supply it. */ + opname = (char *) alloca (IDENTIFIER_LENGTH (function) + + sizeof (argstring) + 25 /*%d*/ + 1); + sprintf (opname, argstring, argnum, IDENTIFIER_POINTER (function)); + } + else + { + /* Function name unknown (call through ptr); just give arg number. */ + opname = (char *) alloca (sizeof (argnofun) + 25 /*%d*/ + 1); + sprintf (opname, argnofun, argnum); + } + } + pedwarn (msg, opname); +} + +/* Return nonzero if VALUE is a valid constant-valued expression + for use in initializing a static variable; one that can be an + element of a "constant" initializer. + + Return null_pointer_node if the value is absolute; + if it is relocatable, return the variable that determines the relocation. + We assume that VALUE has been folded as much as possible; + therefore, we do not need to check for such things as + arithmetic-combinations of integers. */ + +tree +initializer_constant_valid_p (value, endtype) + tree value; + tree endtype; +{ + switch (TREE_CODE (value)) + { + case CONSTRUCTOR: + if (TREE_CODE (TREE_TYPE (value)) == UNION_TYPE + && TREE_CONSTANT (value)) + return + initializer_constant_valid_p (TREE_VALUE (CONSTRUCTOR_ELTS (value)), + endtype); + + return TREE_STATIC (value) ? null_pointer_node : 0; + + case INTEGER_CST: + case REAL_CST: + case STRING_CST: + case COMPLEX_CST: + return null_pointer_node; + + case ADDR_EXPR: + return TREE_OPERAND (value, 0); + + case NON_LVALUE_EXPR: + return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype); + + case CONVERT_EXPR: + case NOP_EXPR: + /* Allow conversions between pointer types. */ + if (TREE_CODE (TREE_TYPE (value)) == POINTER_TYPE + && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == POINTER_TYPE) + return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype); + + /* Allow conversions between real types. */ + if (TREE_CODE (TREE_TYPE (value)) == REAL_TYPE + && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == REAL_TYPE) + return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype); + + /* Allow length-preserving conversions between integer types. */ + if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE + && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE + && (TYPE_PRECISION (TREE_TYPE (value)) + == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))) + return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype); + + /* Allow conversions between other integer types only if + explicit value. */ + if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE + && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE) + { + tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0), + endtype); + if (inner == null_pointer_node) + return null_pointer_node; + return 0; + } + + /* Allow (int) &foo provided int is as wide as a pointer. */ + if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE + && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == POINTER_TYPE + && (TYPE_PRECISION (TREE_TYPE (value)) + >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))) + return initializer_constant_valid_p (TREE_OPERAND (value, 0), + endtype); + + /* Likewise conversions from int to pointers. */ + if (TREE_CODE (TREE_TYPE (value)) == POINTER_TYPE + && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == INTEGER_TYPE + && (TYPE_PRECISION (TREE_TYPE (value)) + <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))) + return initializer_constant_valid_p (TREE_OPERAND (value, 0), + endtype); + + /* Allow conversions to union types if the value inside is okay. */ + if (TREE_CODE (TREE_TYPE (value)) == UNION_TYPE) + return initializer_constant_valid_p (TREE_OPERAND (value, 0), + endtype); + return 0; + + case PLUS_EXPR: + if (TREE_CODE (endtype) == INTEGER_TYPE + && TYPE_PRECISION (endtype) < POINTER_SIZE) + return 0; + { + tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0), + endtype); + tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1), + endtype); + /* If either term is absolute, use the other terms relocation. */ + if (valid0 == null_pointer_node) + return valid1; + if (valid1 == null_pointer_node) + return valid0; + return 0; + } + + case MINUS_EXPR: + if (TREE_CODE (endtype) == INTEGER_TYPE + && TYPE_PRECISION (endtype) < POINTER_SIZE) + return 0; + { + tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0), + endtype); + tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1), + endtype); + /* Win if second argument is absolute. */ + if (valid1 == null_pointer_node) + return valid0; + /* Win if both arguments have the same relocation. + Then the value is absolute. */ + if (valid0 == valid1) + return null_pointer_node; + return 0; + } + } + + return 0; +} + +/* If VALUE is a compound expr all of whose expressions are constant, then + return its value. Otherwise, return error_mark_node. + + This is for handling COMPOUND_EXPRs as initializer elements + which is allowed with a warning when -pedantic is specified. */ + +static tree +valid_compound_expr_initializer (value, endtype) + tree value; + tree endtype; +{ + if (TREE_CODE (value) == COMPOUND_EXPR) + { + if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype) + == error_mark_node) + return error_mark_node; + return valid_compound_expr_initializer (TREE_OPERAND (value, 1), + endtype); + } + else if (! TREE_CONSTANT (value) + && ! initializer_constant_valid_p (value, endtype)) + return error_mark_node; + else + return value; +} + +/* Perform appropriate conversions on the initial value of a variable, + store it in the declaration DECL, + and print any error messages that are appropriate. + If the init is invalid, store an ERROR_MARK. */ + +void +store_init_value (decl, init) + tree decl, init; +{ + register tree value, type; + + /* If variable's type was invalidly declared, just ignore it. */ + + type = TREE_TYPE (decl); + if (TREE_CODE (type) == ERROR_MARK) + return; + + /* Digest the specified initializer into an expression. */ + + value = digest_init (type, init, TREE_STATIC (decl), + TREE_STATIC (decl) || pedantic); + + /* Store the expression if valid; else report error. */ + +#if 0 + /* Note that this is the only place we can detect the error + in a case such as struct foo bar = (struct foo) { x, y }; + where there is one initial value which is a constructor expression. */ + if (value == error_mark_node) + ; + else if (TREE_STATIC (decl) && ! TREE_CONSTANT (value)) + { + error ("initializer for static variable is not constant"); + value = error_mark_node; + } + else if (TREE_STATIC (decl) + && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0) + { + error ("initializer for static variable uses complicated arithmetic"); + value = error_mark_node; + } + else + { + if (pedantic && TREE_CODE (value) == CONSTRUCTOR) + { + if (! TREE_CONSTANT (value)) + pedwarn ("aggregate initializer is not constant"); + else if (! TREE_STATIC (value)) + pedwarn ("aggregate initializer uses complicated arithmetic"); + } + } +#endif + + DECL_INITIAL (decl) = value; + + /* ANSI wants warnings about out-of-range constant initializers. */ + STRIP_TYPE_NOPS (value); + constant_expression_warning (value); +} + +/* Methods for storing and printing names for error messages. */ + +/* Implement a spelling stack that allows components of a name to be pushed + and popped. Each element on the stack is this structure. */ + +struct spelling +{ + int kind; + union + { + int i; + char *s; + } u; +}; + +#define SPELLING_STRING 1 +#define SPELLING_MEMBER 2 +#define SPELLING_BOUNDS 3 + +static struct spelling *spelling; /* Next stack element (unused). */ +static struct spelling *spelling_base; /* Spelling stack base. */ +static int spelling_size; /* Size of the spelling stack. */ + +/* Macros to save and restore the spelling stack around push_... functions. + Alternative to SAVE_SPELLING_STACK. */ + +#define SPELLING_DEPTH() (spelling - spelling_base) +#define RESTORE_SPELLING_DEPTH(depth) (spelling = spelling_base + depth) + +/* Save and restore the spelling stack around arbitrary C code. */ + +#define SAVE_SPELLING_DEPTH(code) \ +{ \ + int __depth = SPELLING_DEPTH (); \ + code; \ + RESTORE_SPELLING_DEPTH (__depth); \ +} + +/* Push an element on the spelling stack with type KIND and assign VALUE + to MEMBER. */ + +#define PUSH_SPELLING(KIND, VALUE, MEMBER) \ +{ \ + int depth = SPELLING_DEPTH (); \ + \ + if (depth >= spelling_size) \ + { \ + spelling_size += 10; \ + if (spelling_base == 0) \ + spelling_base \ + = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \ + else \ + spelling_base \ + = (struct spelling *) xrealloc (spelling_base, \ + spelling_size * sizeof (struct spelling)); \ + RESTORE_SPELLING_DEPTH (depth); \ + } \ + \ + spelling->kind = (KIND); \ + spelling->MEMBER = (VALUE); \ + spelling++; \ +} + +/* Push STRING on the stack. Printed literally. */ + +static void +push_string (string) + char *string; +{ + PUSH_SPELLING (SPELLING_STRING, string, u.s); +} + +/* Push a member name on the stack. Printed as '.' STRING. */ + +static void +push_member_name (decl) + tree decl; + +{ + char *string + = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>"; + PUSH_SPELLING (SPELLING_MEMBER, string, u.s); +} + +/* Push an array bounds on the stack. Printed as [BOUNDS]. */ + +static void +push_array_bounds (bounds) + int bounds; +{ + PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i); +} + +/* Compute the maximum size in bytes of the printed spelling. */ + +static int +spelling_length () +{ + register int size = 0; + register struct spelling *p; + + for (p = spelling_base; p < spelling; p++) + { + if (p->kind == SPELLING_BOUNDS) + size += 25; + else + size += strlen (p->u.s) + 1; + } + + return size; +} + +/* Print the spelling to BUFFER and return it. */ + +static char * +print_spelling (buffer) + register char *buffer; +{ + register char *d = buffer; + register char *s; + register struct spelling *p; + + for (p = spelling_base; p < spelling; p++) + if (p->kind == SPELLING_BOUNDS) + { + sprintf (d, "[%d]", p->u.i); + d += strlen (d); + } + else + { + if (p->kind == SPELLING_MEMBER) + *d++ = '.'; + for (s = p->u.s; *d = *s++; d++) + ; + } + *d++ = '\0'; + return buffer; +} + +/* Provide a means to pass component names derived from the spelling stack. */ + +char initialization_message; + +/* Interpret the spelling of the given ERRTYPE message. */ + +static char * +get_spelling (errtype) + char *errtype; +{ + static char *buffer; + static int size = -1; + + if (errtype == &initialization_message) + { + /* Avoid counting chars */ + static char message[] = "initialization of `%s'"; + register int needed = sizeof (message) + spelling_length () + 1; + char *temp; + + if (size < 0) + buffer = (char *) xmalloc (size = needed); + if (needed > size) + buffer = (char *) xrealloc (buffer, size = needed); + + temp = (char *) alloca (needed); + sprintf (buffer, message, print_spelling (temp)); + return buffer; + } + + return errtype; +} + +/* Issue an error message for a bad initializer component. + FORMAT describes the message. OFWHAT is the name for the component. + LOCAL is a format string for formatting the insertion of the name + into the message. + + If OFWHAT is null, the component name is stored on the spelling stack. + If the component name is a null string, then LOCAL is omitted entirely. */ + +void +error_init (format, local, ofwhat) + char *format, *local, *ofwhat; +{ + char *buffer; + + if (ofwhat == 0) + ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); + buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2); + + if (*ofwhat) + sprintf (buffer, local, ofwhat); + else + buffer[0] = 0; + + error (format, buffer); +} + +/* Issue a pedantic warning for a bad initializer component. + FORMAT describes the message. OFWHAT is the name for the component. + LOCAL is a format string for formatting the insertion of the name + into the message. + + If OFWHAT is null, the component name is stored on the spelling stack. + If the component name is a null string, then LOCAL is omitted entirely. */ + +void +pedwarn_init (format, local, ofwhat) + char *format, *local, *ofwhat; +{ + char *buffer; + + if (ofwhat == 0) + ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); + buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2); + + if (*ofwhat) + sprintf (buffer, local, ofwhat); + else + buffer[0] = 0; + + pedwarn (format, buffer); +} + +/* Issue a warning for a bad initializer component. + FORMAT describes the message. OFWHAT is the name for the component. + LOCAL is a format string for formatting the insertion of the name + into the message. + + If OFWHAT is null, the component name is stored on the spelling stack. + If the component name is a null string, then LOCAL is omitted entirely. */ + +static void +warning_init (format, local, ofwhat) + char *format, *local, *ofwhat; +{ + char *buffer; + + if (ofwhat == 0) + ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); + buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2); + + if (*ofwhat) + sprintf (buffer, local, ofwhat); + else + buffer[0] = 0; + + warning (format, buffer); +} + +/* Digest the parser output INIT as an initializer for type TYPE. + Return a C expression of type TYPE to represent the initial value. + + The arguments REQUIRE_CONSTANT and CONSTRUCTOR_CONSTANT request errors + if non-constant initializers or elements are seen. CONSTRUCTOR_CONSTANT + applies only to elements of constructors. */ + +static tree +digest_init (type, init, require_constant, constructor_constant) + tree type, init; + int require_constant, constructor_constant; +{ + enum tree_code code = TREE_CODE (type); + tree inside_init = init; + + if (init == error_mark_node) + return init; + + /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ + /* Do not use STRIP_NOPS here. We do not want an enumerator + whose value is 0 to count as a null pointer constant. */ + if (TREE_CODE (init) == NON_LVALUE_EXPR) + inside_init = TREE_OPERAND (init, 0); + + /* Initialization of an array of chars from a string constant + optionally enclosed in braces. */ + + if (code == ARRAY_TYPE) + { + tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type)); + if ((typ1 == char_type_node + || typ1 == signed_char_type_node + || typ1 == unsigned_char_type_node + || typ1 == unsigned_wchar_type_node + || typ1 == signed_wchar_type_node) + && ((inside_init && TREE_CODE (inside_init) == STRING_CST))) + { + if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), + TYPE_MAIN_VARIANT (type))) + return inside_init; + + if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init))) + != char_type_node) + && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node)) + { + error_init ("char-array%s initialized from wide string", + " `%s'", NULL); + return error_mark_node; + } + if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init))) + == char_type_node) + && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node)) + { + error_init ("int-array%s initialized from non-wide string", + " `%s'", NULL); + return error_mark_node; + } + + TREE_TYPE (inside_init) = type; + if (TYPE_DOMAIN (type) != 0 + && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST) + { + register int size = TREE_INT_CST_LOW (TYPE_SIZE (type)); + size = (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT; + /* Subtract 1 (or sizeof (wchar_t)) + because it's ok to ignore the terminating null char + that is counted in the length of the constant. */ + if (size < TREE_STRING_LENGTH (inside_init) + - (TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node) + ? TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT + : 1)) + pedwarn_init ( + "initializer-string for array of chars%s is too long", + " `%s'", NULL); + } + return inside_init; + } + } + + /* Any type can be initialized + from an expression of the same type, optionally with braces. */ + + if (inside_init && TREE_TYPE (inside_init) != 0 + && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), + TYPE_MAIN_VARIANT (type)) + || (code == ARRAY_TYPE + && comptypes (TREE_TYPE (inside_init), type)) + || (code == POINTER_TYPE + && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE + || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE) + && comptypes (TREE_TYPE (TREE_TYPE (inside_init)), + TREE_TYPE (type))))) + { + if (code == POINTER_TYPE + && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE + || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE)) + inside_init = default_conversion (inside_init); + else if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST + && TREE_CODE (inside_init) != CONSTRUCTOR) + { + error_init ("array%s initialized from non-constant array expression", + " `%s'", NULL); + return error_mark_node; + } + + if (optimize && TREE_CODE (inside_init) == VAR_DECL) + inside_init = decl_constant_value (inside_init); + + /* Compound expressions can only occur here if -pedantic or + -pedantic-errors is specified. In the later case, we always want + an error. In the former case, we simply want a warning. */ + if (require_constant && pedantic + && TREE_CODE (inside_init) == COMPOUND_EXPR) + { + inside_init + = valid_compound_expr_initializer (inside_init, + TREE_TYPE (inside_init)); + if (inside_init == error_mark_node) + error_init ("initializer element%s is not constant", + " for `%s'", NULL); + else + pedwarn_init ("initializer element%s is not constant", + " for `%s'", NULL); + if (flag_pedantic_errors) + inside_init = error_mark_node; + } + else if (require_constant && ! TREE_CONSTANT (inside_init)) + { + error_init ("initializer element%s is not constant", + " for `%s'", NULL); + inside_init = error_mark_node; + } + else if (require_constant + && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0) + { + error_init ("initializer element%s is not computable at load time", + " for `%s'", NULL); + inside_init = error_mark_node; + } + + return inside_init; + } + + /* Handle scalar types, including conversions. */ + + if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE + || code == ENUMERAL_TYPE || code == COMPLEX_TYPE) + { + /* Note that convert_for_assignment calls default_conversion + for arrays and functions. We must not call it in the + case where inside_init is a null pointer constant. */ + inside_init + = convert_for_assignment (type, init, "initialization", + NULL_TREE, NULL_TREE, 0); + + if (require_constant && ! TREE_CONSTANT (inside_init)) + { + error_init ("initializer element%s is not constant", + " for `%s'", NULL); + inside_init = error_mark_node; + } + else if (require_constant + && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0) + { + error_init ("initializer element%s is not computable at load time", + " for `%s'", NULL); + inside_init = error_mark_node; + } + + return inside_init; + } + + /* Come here only for records and arrays. */ + + if (TYPE_SIZE (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) + { + error_init ("variable-sized object%s may not be initialized", + " `%s'", NULL); + return error_mark_node; + } + + /* Traditionally, you can write struct foo x = 0; + and it initializes the first element of x to 0. */ + if (flag_traditional) + { + tree top = 0, prev = 0; + while (TREE_CODE (type) == RECORD_TYPE + || TREE_CODE (type) == ARRAY_TYPE + || TREE_CODE (type) == QUAL_UNION_TYPE + || TREE_CODE (type) == UNION_TYPE) + { + tree temp = build (CONSTRUCTOR, type, NULL_TREE, NULL_TREE); + if (prev == 0) + top = temp; + else + TREE_OPERAND (prev, 1) = build_tree_list (NULL_TREE, temp); + prev = temp; + if (TREE_CODE (type) == ARRAY_TYPE) + type = TREE_TYPE (type); + else if (TYPE_FIELDS (type)) + type = TREE_TYPE (TYPE_FIELDS (type)); + else + { + error_init ("invalid initializer%s", " for `%s'", NULL); + return error_mark_node; + } + } + TREE_OPERAND (prev, 1) + = build_tree_list (NULL_TREE, + digest_init (type, init, require_constant, + constructor_constant)); + return top; + } + error_init ("invalid initializer%s", " for `%s'", NULL); + return error_mark_node; +} + +/* Handle initializers that use braces. */ + +/* Type of object we are accumulating a constructor for. + This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */ +static tree constructor_type; + +/* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields + left to fill. */ +static tree constructor_fields; + +/* For an ARRAY_TYPE, this is the specified index + at which to store the next element we get. + This is a special INTEGER_CST node that we modify in place. */ +static tree constructor_index; + +/* For an ARRAY_TYPE, this is the end index of the range + to intitialize with the next element, or NULL in the ordinary case + where the element is used just once. */ +static tree constructor_range_end; + +/* For an ARRAY_TYPE, this is the maximum index. */ +static tree constructor_max_index; + +/* For a RECORD_TYPE, this is the first field not yet written out. */ +static tree constructor_unfilled_fields; + +/* For an ARRAY_TYPE, this is the index of the first element + not yet written out. + This is a special INTEGER_CST node that we modify in place. */ +static tree constructor_unfilled_index; + +/* In a RECORD_TYPE, the byte index of the next consecutive field. + This is so we can generate gaps between fields, when appropriate. + This is a special INTEGER_CST node that we modify in place. */ +static tree constructor_bit_index; + +/* If we are saving up the elements rather than allocating them, + this is the list of elements so far (in reverse order, + most recent first). */ +static tree constructor_elements; + +/* 1 if so far this constructor's elements are all compile-time constants. */ +static int constructor_constant; + +/* 1 if so far this constructor's elements are all valid address constants. */ +static int constructor_simple; + +/* 1 if this constructor is erroneous so far. */ +static int constructor_erroneous; + +/* 1 if have called defer_addressed_constants. */ +static int constructor_subconstants_deferred; + +/* List of pending elements at this constructor level. + These are elements encountered out of order + which belong at places we haven't reached yet in actually + writing the output. */ +static tree constructor_pending_elts; + +/* The SPELLING_DEPTH of this constructor. */ +static int constructor_depth; + +/* 0 if implicitly pushing constructor levels is allowed. */ +int constructor_no_implicit = 0; /* 0 for C; 1 for some other languages. */ + +/* 1 if this constructor level was entered implicitly. */ +static int constructor_implicit; + +static int require_constant_value; +static int require_constant_elements; + +/* 1 if it is ok to output this constructor as we read it. + 0 means must accumulate a CONSTRUCTOR expression. */ +static int constructor_incremental; + +/* DECL node for which an initializer is being read. + 0 means we are reading a constructor expression + such as (struct foo) {...}. */ +static tree constructor_decl; + +/* start_init saves the ASMSPEC arg here for really_start_incremental_init. */ +static char *constructor_asmspec; + +/* Nonzero if this is an initializer for a top-level decl. */ +static int constructor_top_level; + +/* When we finish reading a constructor expression + (constructor_decl is 0), the CONSTRUCTOR goes here. */ +static tree constructor_result; + +/* This stack has a level for each implicit or explicit level of + structuring in the initializer, including the outermost one. It + saves the values of most of the variables above. */ + +struct constructor_stack +{ + struct constructor_stack *next; + tree type; + tree fields; + tree index; + tree range_end; + tree max_index; + tree unfilled_index; + tree unfilled_fields; + tree bit_index; + tree elements; + int offset; + tree pending_elts; + int depth; + /* If nonzero, this value should replace the entire + constructor at this level. */ + tree replacement_value; + char constant; + char simple; + char implicit; + char incremental; + char erroneous; + char outer; +}; + +struct constructor_stack *constructor_stack; + +/* This stack records separate initializers that are nested. + Nested initializers can't happen in ANSI C, but GNU C allows them + in cases like { ... (struct foo) { ... } ... }. */ + +struct initializer_stack +{ + struct initializer_stack *next; + tree decl; + char *asmspec; + struct constructor_stack *constructor_stack; + tree elements; + struct spelling *spelling; + struct spelling *spelling_base; + int spelling_size; + char top_level; + char incremental; + char require_constant_value; + char require_constant_elements; + char deferred; +}; + +struct initializer_stack *initializer_stack; + +/* Prepare to parse and output the initializer for variable DECL. */ + +void +start_init (decl, asmspec_tree, top_level) + tree decl; + tree asmspec_tree; + int top_level; +{ + char *locus; + struct initializer_stack *p + = (struct initializer_stack *) xmalloc (sizeof (struct initializer_stack)); + char *asmspec = 0; + + if (asmspec_tree) + asmspec = TREE_STRING_POINTER (asmspec_tree); + + p->decl = constructor_decl; + p->asmspec = constructor_asmspec; + p->incremental = constructor_incremental; + p->require_constant_value = require_constant_value; + p->require_constant_elements = require_constant_elements; + p->constructor_stack = constructor_stack; + p->elements = constructor_elements; + p->spelling = spelling; + p->spelling_base = spelling_base; + p->spelling_size = spelling_size; + p->deferred = constructor_subconstants_deferred; + p->top_level = constructor_top_level; + p->next = initializer_stack; + initializer_stack = p; + + constructor_decl = decl; + constructor_incremental = top_level; + constructor_asmspec = asmspec; + constructor_subconstants_deferred = 0; + constructor_top_level = top_level; + + if (decl != 0) + { + require_constant_value = TREE_STATIC (decl); + require_constant_elements + = ((TREE_STATIC (decl) || pedantic) + /* For a scalar, you can always use any value to initialize, + even within braces. */ + && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE + || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE + || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE + || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE)); + locus = IDENTIFIER_POINTER (DECL_NAME (decl)); + constructor_incremental |= TREE_STATIC (decl); + } + else + { + require_constant_value = 0; + require_constant_elements = 0; + locus = "(anonymous)"; + } + + constructor_stack = 0; + + missing_braces_mentioned = 0; + + spelling_base = 0; + spelling_size = 0; + RESTORE_SPELLING_DEPTH (0); + + if (locus) + push_string (locus); +} + +void +finish_init () +{ + struct initializer_stack *p = initializer_stack; + + /* Output subconstants (string constants, usually) + that were referenced within this initializer and saved up. + Must do this if and only if we called defer_addressed_constants. */ + if (constructor_subconstants_deferred) + output_deferred_addressed_constants (); + + /* Free the whole constructor stack of this initializer. */ + while (constructor_stack) + { + struct constructor_stack *q = constructor_stack; + constructor_stack = q->next; + free (q); + } + + /* Pop back to the data of the outer initializer (if any). */ + constructor_decl = p->decl; + constructor_asmspec = p->asmspec; + constructor_incremental = p->incremental; + require_constant_value = p->require_constant_value; + require_constant_elements = p->require_constant_elements; + constructor_stack = p->constructor_stack; + constructor_elements = p->elements; + spelling = p->spelling; + spelling_base = p->spelling_base; + spelling_size = p->spelling_size; + constructor_subconstants_deferred = p->deferred; + constructor_top_level = p->top_level; + initializer_stack = p->next; + free (p); +} + +/* Call here when we see the initializer is surrounded by braces. + This is instead of a call to push_init_level; + it is matched by a call to pop_init_level. + + TYPE is the type to initialize, for a constructor expression. + For an initializer for a decl, TYPE is zero. */ + +void +really_start_incremental_init (type) + tree type; +{ + struct constructor_stack *p + = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack)); + + if (type == 0) + type = TREE_TYPE (constructor_decl); + + /* Turn off constructor_incremental if type is a struct with bitfields. + Do this before the first push, so that the corrected value + is available in finish_init. */ + check_init_type_bitfields (type); + + p->type = constructor_type; + p->fields = constructor_fields; + p->index = constructor_index; + p->range_end = constructor_range_end; + p->max_index = constructor_max_index; + p->unfilled_index = constructor_unfilled_index; + p->unfilled_fields = constructor_unfilled_fields; + p->bit_index = constructor_bit_index; + p->elements = constructor_elements; + p->constant = constructor_constant; + p->simple = constructor_simple; + p->erroneous = constructor_erroneous; + p->pending_elts = constructor_pending_elts; + p->depth = constructor_depth; + p->replacement_value = 0; + p->implicit = 0; + p->incremental = constructor_incremental; + p->outer = 0; + p->next = 0; + constructor_stack = p; + + constructor_constant = 1; + constructor_simple = 1; + constructor_depth = SPELLING_DEPTH (); + constructor_elements = 0; + constructor_pending_elts = 0; + constructor_type = type; + + if (TREE_CODE (constructor_type) == RECORD_TYPE + || TREE_CODE (constructor_type) == UNION_TYPE) + { + constructor_fields = TYPE_FIELDS (constructor_type); + /* Skip any nameless bit fields atthe beginning. */ + while (constructor_fields != 0 && DECL_BIT_FIELD (constructor_fields) + && DECL_NAME (constructor_fields) == 0) + constructor_fields = TREE_CHAIN (constructor_fields); + constructor_unfilled_fields = constructor_fields; + constructor_bit_index = copy_node (integer_zero_node); + } + else if (TREE_CODE (constructor_type) == ARRAY_TYPE) + { + constructor_range_end = 0; + if (TYPE_DOMAIN (constructor_type)) + { + constructor_max_index + = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)); + constructor_index + = copy_node (TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); + } + else + constructor_index = copy_node (integer_zero_node); + constructor_unfilled_index = copy_node (constructor_index); + } + else + { + /* Handle the case of int x = {5}; */ + constructor_fields = constructor_type; + constructor_unfilled_fields = constructor_type; + } + + if (constructor_incremental) + { + int momentary = suspend_momentary (); + push_obstacks_nochange (); + if (TREE_PERMANENT (constructor_decl)) + end_temporary_allocation (); + make_decl_rtl (constructor_decl, constructor_asmspec, + constructor_top_level); + assemble_variable (constructor_decl, constructor_top_level, 0, 1); + pop_obstacks (); + resume_momentary (momentary); + } + + if (constructor_incremental) + { + defer_addressed_constants (); + constructor_subconstants_deferred = 1; + } +} + +/* Push down into a subobject, for initialization. + If this is for an explicit set of braces, IMPLICIT is 0. + If it is because the next element belongs at a lower level, + IMPLICIT is 1. */ + +void +push_init_level (implicit) + int implicit; +{ + struct constructor_stack *p; + + /* If we've exhausted any levels that didn't have braces, + pop them now. */ + while (constructor_stack->implicit) + { + if ((TREE_CODE (constructor_type) == RECORD_TYPE + || TREE_CODE (constructor_type) == UNION_TYPE) + && constructor_fields == 0) + process_init_element (pop_init_level (1)); + else if (TREE_CODE (constructor_type) == ARRAY_TYPE + && tree_int_cst_lt (constructor_max_index, constructor_index)) + process_init_element (pop_init_level (1)); + else + break; + } + + /* Structure elements may require alignment. Do this now + if necessary for the subaggregate. */ + if (constructor_incremental && TREE_CODE (constructor_type) == RECORD_TYPE + && constructor_fields) + { + /* Advance to offset of this element. */ + if (! tree_int_cst_equal (constructor_bit_index, + DECL_FIELD_BITPOS (constructor_fields))) + { + int next = (TREE_INT_CST_LOW + (DECL_FIELD_BITPOS (constructor_fields)) + / BITS_PER_UNIT); + int here = (TREE_INT_CST_LOW (constructor_bit_index) + / BITS_PER_UNIT); + + assemble_zeros (next - here); + } + } + + p = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack)); + p->type = constructor_type; + p->fields = constructor_fields; + p->index = constructor_index; + p->range_end = constructor_range_end; + p->max_index = constructor_max_index; + p->unfilled_index = constructor_unfilled_index; + p->unfilled_fields = constructor_unfilled_fields; + p->bit_index = constructor_bit_index; + p->elements = constructor_elements; + p->constant = constructor_constant; + p->simple = constructor_simple; + p->erroneous = constructor_erroneous; + p->pending_elts = constructor_pending_elts; + p->depth = constructor_depth; + p->replacement_value = 0; + p->implicit = implicit; + p->incremental = constructor_incremental; + p->outer = 0; + p->next = constructor_stack; + constructor_stack = p; + + constructor_constant = 1; + constructor_simple = 1; + constructor_depth = SPELLING_DEPTH (); + constructor_elements = 0; + constructor_pending_elts = 0; + + /* Don't die if an entire brace-pair level is superfluous + in the containing level. */ + if (constructor_type == 0) + ; + else if (TREE_CODE (constructor_type) == RECORD_TYPE + || TREE_CODE (constructor_type) == UNION_TYPE) + { + /* Don't die if there are extra init elts at the end. */ + if (constructor_fields == 0) + constructor_type = 0; + else + { + constructor_type = TREE_TYPE (constructor_fields); + push_member_name (constructor_fields); + if (constructor_fields != constructor_unfilled_fields) + constructor_incremental = 0; + } + } + else if (TREE_CODE (constructor_type) == ARRAY_TYPE) + { + constructor_type = TREE_TYPE (constructor_type); + push_array_bounds (TREE_INT_CST_LOW (constructor_index)); + if (! tree_int_cst_equal (constructor_index, constructor_unfilled_index) + || constructor_range_end != 0) + constructor_incremental = 0; + } + + if (constructor_type == 0) + { + error_init ("extra brace group at end of initializer%s", + " for `%s'", NULL); + constructor_fields = 0; + constructor_unfilled_fields = 0; + return; + } + + /* Turn off constructor_incremental if type is a struct with bitfields. */ + check_init_type_bitfields (constructor_type); + + if (implicit && warn_missing_braces && !missing_braces_mentioned) + { + missing_braces_mentioned = 1; + warning_init ("missing braces around initializer%s", " for `%s'", NULL); + } + + if (TREE_CODE (constructor_type) == RECORD_TYPE + || TREE_CODE (constructor_type) == UNION_TYPE) + { + constructor_fields = TYPE_FIELDS (constructor_type); + /* Skip any nameless bit fields atthe beginning. */ + while (constructor_fields != 0 && DECL_BIT_FIELD (constructor_fields) + && DECL_NAME (constructor_fields) == 0) + constructor_fields = TREE_CHAIN (constructor_fields); + constructor_unfilled_fields = constructor_fields; + constructor_bit_index = copy_node (integer_zero_node); + } + else if (TREE_CODE (constructor_type) == ARRAY_TYPE) + { + constructor_range_end = 0; + if (TYPE_DOMAIN (constructor_type)) + { + constructor_max_index + = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)); + constructor_index + = copy_node (TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); + } + else + constructor_index = copy_node (integer_zero_node); + constructor_unfilled_index = copy_node (constructor_index); + } + else + { + warning_init ("braces around scalar initializer%s", " for `%s'", NULL); + constructor_fields = constructor_type; + constructor_unfilled_fields = constructor_type; + } +} + +/* Don't read a struct incrementally if it has any bitfields, + because the incremental reading code doesn't know how to + handle bitfields yet. */ + +static void +check_init_type_bitfields (type) + tree type; +{ + if (TREE_CODE (type) == RECORD_TYPE) + { + tree tail; + for (tail = TYPE_FIELDS (type); tail; + tail = TREE_CHAIN (tail)) + { + if (DECL_BIT_FIELD (tail) + /* This catches cases like `int foo : 8;'. */ + || DECL_MODE (tail) != TYPE_MODE (TREE_TYPE (tail))) + { + constructor_incremental = 0; + break; + } + + check_init_type_bitfields (TREE_TYPE (tail)); + } + } + + else if (TREE_CODE (type) == ARRAY_TYPE) + check_init_type_bitfields (TREE_TYPE (type)); +} + +/* At the end of an implicit or explicit brace level, + finish up that level of constructor. + If we were outputting the elements as they are read, return 0 + from inner levels (process_init_element ignores that), + but return error_mark_node from the outermost level + (that's what we want to put in DECL_INITIAL). + Otherwise, return a CONSTRUCTOR expression. */ + +tree +pop_init_level (implicit) + int implicit; +{ + struct constructor_stack *p; + int size = 0; + tree constructor = 0; + + if (implicit == 0) + { + /* When we come to an explicit close brace, + pop any inner levels that didn't have explicit braces. */ + while (constructor_stack->implicit) + process_init_element (pop_init_level (1)); + } + + p = constructor_stack; + + if (constructor_type != 0) + size = int_size_in_bytes (constructor_type); + + /* Now output all pending elements. */ + output_pending_init_elements (1); + +#if 0 /* c-parse.in warns about {}. */ + /* In ANSI, each brace level must have at least one element. */ + if (! implicit && pedantic + && (TREE_CODE (constructor_type) == ARRAY_TYPE + ? integer_zerop (constructor_unfilled_index) + : constructor_unfilled_fields == TYPE_FIELDS (constructor_type))) + pedwarn_init ("empty braces in initializer%s", " for `%s'", NULL); +#endif + + /* Pad out the end of the structure. */ + + if (p->replacement_value) + { + /* If this closes a superfluous brace pair, + just pass out the element between them. */ + constructor = p->replacement_value; + /* If this is the top level thing within the initializer, + and it's for a variable, then since we already called + assemble_variable, we must output the value now. */ + if (p->next == 0 && constructor_decl != 0 + && constructor_incremental) + { + constructor = digest_init (constructor_type, constructor, + 0, 0); + + /* If initializing an array of unknown size, + determine the size now. */ + if (TREE_CODE (constructor_type) == ARRAY_TYPE + && TYPE_DOMAIN (constructor_type) == 0) + { + int failure; + int momentary_p; + + push_obstacks_nochange (); + if (TREE_PERMANENT (constructor_type)) + end_temporary_allocation (); + + momentary_p = suspend_momentary (); + + /* We shouldn't have an incomplete array type within + some other type. */ + if (constructor_stack->next) + abort (); + + failure + = complete_array_type (constructor_type, + constructor, 0); + if (failure) + abort (); + + size = int_size_in_bytes (constructor_type); + resume_momentary (momentary_p); + pop_obstacks (); + } + + output_constant (constructor, size); + } + } + else if (constructor_type == 0) + ; + else if (TREE_CODE (constructor_type) != RECORD_TYPE + && TREE_CODE (constructor_type) != UNION_TYPE + && TREE_CODE (constructor_type) != ARRAY_TYPE + && ! constructor_incremental) + { + /* A nonincremental scalar initializer--just return + the element, after verifying there is just one. */ + if (constructor_elements == 0) + { + error_init ("empty scalar initializer%s", + " for `%s'", NULL); + constructor = error_mark_node; + } + else if (TREE_CHAIN (constructor_elements) != 0) + { + error_init ("extra elements in scalar initializer%s", + " for `%s'", NULL); + constructor = TREE_VALUE (constructor_elements); + } + else + constructor = TREE_VALUE (constructor_elements); + } + else if (! constructor_incremental) + { + if (constructor_erroneous) + constructor = error_mark_node; + else + { + int momentary = suspend_momentary (); + + constructor = build (CONSTRUCTOR, constructor_type, NULL_TREE, + nreverse (constructor_elements)); + if (constructor_constant) + TREE_CONSTANT (constructor) = 1; + if (constructor_constant && constructor_simple) + TREE_STATIC (constructor) = 1; + + resume_momentary (momentary); + } + } + else + { + tree filled; + int momentary = suspend_momentary (); + + if (TREE_CODE (constructor_type) == RECORD_TYPE + || TREE_CODE (constructor_type) == UNION_TYPE) + { + /* Find the offset of the end of that field. */ + filled = size_binop (CEIL_DIV_EXPR, + constructor_bit_index, + size_int (BITS_PER_UNIT)); + } + else if (TREE_CODE (constructor_type) == ARRAY_TYPE) + { + /* If initializing an array of unknown size, + determine the size now. */ + if (TREE_CODE (constructor_type) == ARRAY_TYPE + && TYPE_DOMAIN (constructor_type) == 0) + { + tree maxindex + = size_binop (MINUS_EXPR, + constructor_unfilled_index, + integer_one_node); + + push_obstacks_nochange (); + if (TREE_PERMANENT (constructor_type)) + end_temporary_allocation (); + maxindex = copy_node (maxindex); + TYPE_DOMAIN (constructor_type) = build_index_type (maxindex); + TREE_TYPE (maxindex) = TYPE_DOMAIN (constructor_type); + + /* TYPE_MAX_VALUE is always one less than the number of elements + in the array, because we start counting at zero. Therefore, + warn only if the value is less than zero. */ + if (pedantic + && (tree_int_cst_sgn (TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type))) + < 0)) + error_with_decl (constructor_decl, + "zero or negative array size `%s'"); + layout_type (constructor_type); + size = int_size_in_bytes (constructor_type); + pop_obstacks (); + } + + filled = size_binop (MULT_EXPR, constructor_unfilled_index, + size_in_bytes (TREE_TYPE (constructor_type))); + } + else + filled = 0; + + if (filled != 0) + assemble_zeros (size - TREE_INT_CST_LOW (filled)); + + resume_momentary (momentary); + } + + + constructor_type = p->type; + constructor_fields = p->fields; + constructor_index = p->index; + constructor_range_end = p->range_end; + constructor_max_index = p->max_index; + constructor_unfilled_index = p->unfilled_index; + constructor_unfilled_fields = p->unfilled_fields; + constructor_bit_index = p->bit_index; + constructor_elements = p->elements; + constructor_constant = p->constant; + constructor_simple = p->simple; + constructor_erroneous = p->erroneous; + constructor_pending_elts = p->pending_elts; + constructor_depth = p->depth; + constructor_incremental = p->incremental; + RESTORE_SPELLING_DEPTH (constructor_depth); + + constructor_stack = p->next; + free (p); + + if (constructor == 0) + { + if (constructor_stack == 0) + return error_mark_node; + return NULL_TREE; + } + return constructor; +} + +/* Within an array initializer, specify the next index to be initialized. + FIRST is that index. If LAST is nonzero, then initialize a range + of indices, running from FIRST through LAST. */ + +void +set_init_index (first, last) + tree first, last; +{ + while ((TREE_CODE (first) == NOP_EXPR + || TREE_CODE (first) == CONVERT_EXPR + || TREE_CODE (first) == NON_LVALUE_EXPR) + && (TYPE_MODE (TREE_TYPE (first)) + == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0))))) + (first) = TREE_OPERAND (first, 0); + if (last) + while ((TREE_CODE (last) == NOP_EXPR + || TREE_CODE (last) == CONVERT_EXPR + || TREE_CODE (last) == NON_LVALUE_EXPR) + && (TYPE_MODE (TREE_TYPE (last)) + == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0))))) + (last) = TREE_OPERAND (last, 0); + + if (TREE_CODE (first) != INTEGER_CST) + error_init ("nonconstant array index in initializer%s", " for `%s'", NULL); + else if (last != 0 && TREE_CODE (last) != INTEGER_CST) + error_init ("nonconstant array index in initializer%s", " for `%s'", NULL); + else if (tree_int_cst_lt (first, constructor_unfilled_index)) + error_init ("duplicate array index in initializer%s", " for `%s'", NULL); + else + { + TREE_INT_CST_LOW (constructor_index) + = TREE_INT_CST_LOW (first); + TREE_INT_CST_HIGH (constructor_index) + = TREE_INT_CST_HIGH (first); + + if (last != 0 && tree_int_cst_lt (last, first)) + error_init ("empty index range in initializer%s", " for `%s'", NULL); + else + { + if (pedantic) + pedwarn ("ANSI C forbids specifying element to initialize"); + constructor_range_end = last; + } + } +} + +/* Within a struct initializer, specify the next field to be initialized. */ + +void +set_init_label (fieldname) + tree fieldname; +{ + tree tail; + int passed = 0; + + for (tail = TYPE_FIELDS (constructor_type); tail; + tail = TREE_CHAIN (tail)) + { + if (tail == constructor_unfilled_fields) + passed = 1; + if (DECL_NAME (tail) == fieldname) + break; + } + + if (tail == 0) + error ("unknown field `%s' specified in initializer", + IDENTIFIER_POINTER (fieldname)); + else if (!passed) + error ("field `%s' already initialized", + IDENTIFIER_POINTER (fieldname)); + else + { + constructor_fields = tail; + if (pedantic) + pedwarn ("ANSI C forbids specifying structure member to initialize"); + } +} + +/* "Output" the next constructor element. + At top level, really output it to assembler code now. + Otherwise, collect it in a list from which we will make a CONSTRUCTOR. + TYPE is the data type that the containing data type wants here. + FIELD is the field (a FIELD_DECL) or the index that this element fills. + + PENDING if non-nil means output pending elements that belong + right after this element. (PENDING is normally 1; + it is 0 while outputting pending elements, to avoid recursion.) */ + +static void +output_init_element (value, type, field, pending) + tree value, type, field; + int pending; +{ + int duplicate = 0; + + if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE + || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE + && !(TREE_CODE (value) == STRING_CST + && TREE_CODE (type) == ARRAY_TYPE + && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE) + && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)), + TYPE_MAIN_VARIANT (type)))) + value = default_conversion (value); + + if (value == error_mark_node) + constructor_erroneous = 1; + else if (!TREE_CONSTANT (value)) + constructor_constant = 0; + else if (initializer_constant_valid_p (value, TREE_TYPE (value)) == 0) + constructor_simple = 0; + + if (require_constant_value && ! TREE_CONSTANT (value)) + { + error_init ("initializer element%s is not constant", + " for `%s'", NULL); + value = error_mark_node; + } + else if (require_constant_elements + && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0) + { + error_init ("initializer element%s is not computable at load time", + " for `%s'", NULL); + value = error_mark_node; + } + + /* If this element duplicates one on constructor_pending_elts, + print a message and ignore it. Don't do this when we're + processing elements taken off constructor_pending_elts, + because we'd always get spurious errors. */ + if (pending) + { + if (TREE_CODE (constructor_type) == RECORD_TYPE + || TREE_CODE (constructor_type) == UNION_TYPE) + { + if (purpose_member (field, constructor_pending_elts)) + { + error_init ("duplicate initializer%s", " for `%s'", NULL); + duplicate = 1; + } + } + if (TREE_CODE (constructor_type) == ARRAY_TYPE) + { + tree tail; + for (tail = constructor_pending_elts; tail; + tail = TREE_CHAIN (tail)) + if (TREE_PURPOSE (tail) != 0 + && TREE_CODE (TREE_PURPOSE (tail)) == INTEGER_CST + && tree_int_cst_equal (TREE_PURPOSE (tail), constructor_index)) + break; + + if (tail != 0) + { + error_init ("duplicate initializer%s", " for `%s'", NULL); + duplicate = 1; + } + } + } + + /* If this element doesn't come next in sequence, + put it on constructor_pending_elts. */ + if (TREE_CODE (constructor_type) == ARRAY_TYPE + && !tree_int_cst_equal (field, constructor_unfilled_index)) + { + if (! duplicate) + /* The copy_node is needed in case field is actually + constructor_index, which is modified in place. */ + constructor_pending_elts + = tree_cons (copy_node (field), + digest_init (type, value, 0, 0), + constructor_pending_elts); + } + else if (TREE_CODE (constructor_type) == RECORD_TYPE + && field != constructor_unfilled_fields) + { + /* We do this for records but not for unions. In a union, + no matter which field is specified, it can be initialized + right away since it starts at the beginning of the union. */ + if (!duplicate) + constructor_pending_elts + = tree_cons (field, + digest_init (type, value, 0, 0), + constructor_pending_elts); + } + else + { + /* Otherwise, output this element either to + constructor_elements or to the assembler file. */ + + if (!duplicate) + { + if (! constructor_incremental) + { + if (field && TREE_CODE (field) == INTEGER_CST) + field = copy_node (field); + constructor_elements + = tree_cons (field, digest_init (type, value, 0, 0), + constructor_elements); + } + else + { + /* Structure elements may require alignment. + Do this, if necessary. */ + if (TREE_CODE (constructor_type) == RECORD_TYPE) + { + /* Advance to offset of this element. */ + if (! tree_int_cst_equal (constructor_bit_index, + DECL_FIELD_BITPOS (field))) + { + int next = (TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field)) + / BITS_PER_UNIT); + int here = (TREE_INT_CST_LOW (constructor_bit_index) + / BITS_PER_UNIT); + + assemble_zeros (next - here); + } + } + output_constant (digest_init (type, value, 0, 0), + int_size_in_bytes (type)); + + /* For a record or union, + keep track of end position of last field. */ + if (TREE_CODE (constructor_type) == RECORD_TYPE + || TREE_CODE (constructor_type) == UNION_TYPE) + { + tree temp = size_binop (PLUS_EXPR, DECL_FIELD_BITPOS (field), + DECL_SIZE (field)); + TREE_INT_CST_LOW (constructor_bit_index) + = TREE_INT_CST_LOW (temp); + TREE_INT_CST_HIGH (constructor_bit_index) + = TREE_INT_CST_HIGH (temp); + } + } + } + + /* Advance the variable that indicates sequential elements output. */ + if (TREE_CODE (constructor_type) == ARRAY_TYPE) + { + tree tem = size_binop (PLUS_EXPR, constructor_unfilled_index, + integer_one_node); + TREE_INT_CST_LOW (constructor_unfilled_index) + = TREE_INT_CST_LOW (tem); + TREE_INT_CST_HIGH (constructor_unfilled_index) + = TREE_INT_CST_HIGH (tem); + } + else if (TREE_CODE (constructor_type) == RECORD_TYPE) + constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); + else if (TREE_CODE (constructor_type) == UNION_TYPE) + constructor_unfilled_fields = 0; + + /* Now output any pending elements which have become next. */ + if (pending) + output_pending_init_elements (0); + } +} + +/* Output any pending elements which have become next. + As we output elements, constructor_unfilled_{fields,index} + advances, which may cause other elements to become next; + if so, they too are output. + + If ALL is 0, we return when there are + no more pending elements to output now. + + If ALL is 1, we output space as necessary so that + we can output all the pending elements. */ + +static void +output_pending_init_elements (all) + int all; +{ + tree tail; + tree next; + + retry: + + /* Look thru the whole pending list. + If we find an element that should be output now, + output it. Otherwise, set NEXT to the element + that comes first among those still pending. */ + + next = 0; + for (tail = constructor_pending_elts; tail; + tail = TREE_CHAIN (tail)) + { + if (TREE_CODE (constructor_type) == ARRAY_TYPE) + { + if (tree_int_cst_equal (TREE_PURPOSE (tail), + constructor_unfilled_index)) + { + output_init_element (TREE_VALUE (tail), + TREE_TYPE (constructor_type), + constructor_unfilled_index, 0); + goto retry; + } + else if (tree_int_cst_lt (TREE_PURPOSE (tail), + constructor_unfilled_index)) + ; + else if (next == 0 + || tree_int_cst_lt (TREE_PURPOSE (tail), next)) + next = TREE_PURPOSE (tail); + } + else if (TREE_CODE (constructor_type) == RECORD_TYPE + || TREE_CODE (constructor_type) == UNION_TYPE) + { + if (TREE_PURPOSE (tail) == constructor_unfilled_fields) + { + output_init_element (TREE_VALUE (tail), + TREE_TYPE (constructor_unfilled_fields), + constructor_unfilled_fields, + 0); + goto retry; + } + else if (constructor_unfilled_fields == 0 + || tree_int_cst_lt (DECL_FIELD_BITPOS (TREE_PURPOSE (tail)), + DECL_FIELD_BITPOS (constructor_unfilled_fields))) + ; + else if (next == 0 + || tree_int_cst_lt (DECL_FIELD_BITPOS (TREE_PURPOSE (tail)), + DECL_FIELD_BITPOS (next))) + next = TREE_PURPOSE (tail); + } + } + + /* Ordinarily return, but not if we want to output all + and there are elements left. */ + if (! (all && next != 0)) + return; + + /* Generate space up to the position of NEXT. */ + if (constructor_incremental) + { + tree filled; + tree nextpos_tree = size_int (0); + + if (TREE_CODE (constructor_type) == RECORD_TYPE + || TREE_CODE (constructor_type) == UNION_TYPE) + { + /* Find the last field written out, if any. */ + for (tail = TYPE_FIELDS (constructor_type); tail; + tail = TREE_CHAIN (tail)) + if (TREE_CHAIN (tail) == constructor_unfilled_fields) + break; + + if (tail) + /* Find the offset of the end of that field. */ + filled = size_binop (CEIL_DIV_EXPR, + size_binop (PLUS_EXPR, + DECL_FIELD_BITPOS (tail), + DECL_SIZE (tail)), + size_int (BITS_PER_UNIT)); + else + filled = size_int (0); + + nextpos_tree = size_binop (CEIL_DIV_EXPR, + DECL_FIELD_BITPOS (next), + size_int (BITS_PER_UNIT)); + + TREE_INT_CST_HIGH (constructor_bit_index) + = TREE_INT_CST_HIGH (DECL_FIELD_BITPOS (next)); + TREE_INT_CST_LOW (constructor_bit_index) + = TREE_INT_CST_LOW (DECL_FIELD_BITPOS (next)); + constructor_unfilled_fields = next; + } + else if (TREE_CODE (constructor_type) == ARRAY_TYPE) + { + filled = size_binop (MULT_EXPR, constructor_unfilled_index, + size_in_bytes (TREE_TYPE (constructor_type))); + nextpos_tree + = size_binop (MULT_EXPR, next, + size_in_bytes (TREE_TYPE (constructor_type))); + TREE_INT_CST_LOW (constructor_unfilled_index) + = TREE_INT_CST_LOW (next); + TREE_INT_CST_HIGH (constructor_unfilled_index) + = TREE_INT_CST_HIGH (next); + } + else + filled = 0; + + if (filled) + { + int nextpos = TREE_INT_CST_LOW (nextpos_tree); + + assemble_zeros (nextpos - TREE_INT_CST_LOW (filled)); + } + } + else + { + /* If it's not incremental, just skip over the gap, + so that after jumping to retry we will output the next + successive element. */ + if (TREE_CODE (constructor_type) == RECORD_TYPE + || TREE_CODE (constructor_type) == UNION_TYPE) + constructor_unfilled_fields = next; + else if (TREE_CODE (constructor_type) == ARRAY_TYPE) + { + TREE_INT_CST_LOW (constructor_unfilled_index) + = TREE_INT_CST_LOW (next); + TREE_INT_CST_HIGH (constructor_unfilled_index) + = TREE_INT_CST_HIGH (next); + } + } + + goto retry; +} + +/* Add one non-braced element to the current constructor level. + This adjusts the current position within the constructor's type. + This may also start or terminate implicit levels + to handle a partly-braced initializer. + + Once this has found the correct level for the new element, + it calls output_init_element. + + Note: if we are incrementally outputting this constructor, + this function may be called with a null argument + representing a sub-constructor that was already incrementally output. + When that happens, we output nothing, but we do the bookkeeping + to skip past that element of the current constructor. */ + +void +process_init_element (value) + tree value; +{ + tree orig_value = value; + int string_flag = value != 0 && TREE_CODE (value) == STRING_CST; + + /* Handle superfluous braces around string cst as in + char x[] = {"foo"}; */ + if (string_flag + && constructor_type + && TREE_CODE (constructor_type) == ARRAY_TYPE + && TREE_CODE (TREE_TYPE (constructor_type)) == INTEGER_TYPE + && integer_zerop (constructor_unfilled_index)) + { + constructor_stack->replacement_value = value; + return; + } + + if (constructor_stack->replacement_value != 0) + { + error_init ("excess elements in struct initializer%s", + " after `%s'", NULL_PTR); + return; + } + + /* Ignore elements of a brace group if it is entirely superfluous + and has already been diagnosed. */ + if (constructor_type == 0) + return; + + /* If we've exhausted any levels that didn't have braces, + pop them now. */ + while (constructor_stack->implicit) + { + if ((TREE_CODE (constructor_type) == RECORD_TYPE + || TREE_CODE (constructor_type) == UNION_TYPE) + && constructor_fields == 0) + process_init_element (pop_init_level (1)); + else if (TREE_CODE (constructor_type) == ARRAY_TYPE + && tree_int_cst_lt (constructor_max_index, constructor_index)) + process_init_element (pop_init_level (1)); + else + break; + } + + while (1) + { + if (TREE_CODE (constructor_type) == RECORD_TYPE) + { + tree fieldtype; + enum tree_code fieldcode; + + if (constructor_fields == 0) + { + pedwarn_init ("excess elements in struct initializer%s", + " after `%s'", NULL_PTR); + break; + } + + fieldtype = TREE_TYPE (constructor_fields); + if (fieldtype != error_mark_node) + fieldtype = TYPE_MAIN_VARIANT (fieldtype); + fieldcode = TREE_CODE (fieldtype); + + /* Accept a string constant to initialize a subarray. */ + if (value != 0 + && fieldcode == ARRAY_TYPE + && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE + && string_flag) + value = orig_value; + /* Otherwise, if we have come to a subaggregate, + and we don't have an element of its type, push into it. */ + else if (value != 0 && !constructor_no_implicit + && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype + && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE + || fieldcode == UNION_TYPE)) + { + push_init_level (1); + continue; + } + + if (value) + { + push_member_name (constructor_fields); + output_init_element (value, fieldtype, constructor_fields, 1); + RESTORE_SPELLING_DEPTH (constructor_depth); + } + else + /* Do the bookkeeping for an element that was + directly output as a constructor. */ + { + /* For a record, keep track of end position of last field. */ + tree temp = size_binop (PLUS_EXPR, + DECL_FIELD_BITPOS (constructor_fields), + DECL_SIZE (constructor_fields)); + TREE_INT_CST_LOW (constructor_bit_index) + = TREE_INT_CST_LOW (temp); + TREE_INT_CST_HIGH (constructor_bit_index) + = TREE_INT_CST_HIGH (temp); + + constructor_unfilled_fields = TREE_CHAIN (constructor_fields); + } + + constructor_fields = TREE_CHAIN (constructor_fields); + /* Skip any nameless bit fields atthe beginning. */ + while (constructor_fields != 0 && DECL_BIT_FIELD (constructor_fields) + && DECL_NAME (constructor_fields) == 0) + constructor_fields = TREE_CHAIN (constructor_fields); + break; + } + if (TREE_CODE (constructor_type) == UNION_TYPE) + { + tree fieldtype; + enum tree_code fieldcode; + + if (constructor_fields == 0) + { + pedwarn_init ("excess elements in union initializer%s", + " after `%s'", NULL_PTR); + break; + } + + fieldtype = TREE_TYPE (constructor_fields); + if (fieldtype != error_mark_node) + fieldtype = TYPE_MAIN_VARIANT (fieldtype); + fieldcode = TREE_CODE (fieldtype); + + /* Accept a string constant to initialize a subarray. */ + if (value != 0 + && fieldcode == ARRAY_TYPE + && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE + && string_flag) + value = orig_value; + /* Otherwise, if we have come to a subaggregate, + and we don't have an element of its type, push into it. */ + else if (value != 0 && !constructor_no_implicit + && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype + && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE + || fieldcode == UNION_TYPE)) + { + push_init_level (1); + continue; + } + + if (value) + { + push_member_name (constructor_fields); + output_init_element (value, fieldtype, constructor_fields, 1); + RESTORE_SPELLING_DEPTH (constructor_depth); + } + else + /* Do the bookkeeping for an element that was + directly output as a constructor. */ + { + TREE_INT_CST_LOW (constructor_bit_index) + = TREE_INT_CST_LOW (DECL_SIZE (constructor_fields)); + TREE_INT_CST_HIGH (constructor_bit_index) + = TREE_INT_CST_HIGH (DECL_SIZE (constructor_fields)); + + constructor_unfilled_fields = TREE_CHAIN (constructor_fields); + } + + constructor_fields = 0; + break; + } + if (TREE_CODE (constructor_type) == ARRAY_TYPE) + { + tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); + enum tree_code eltcode = TREE_CODE (elttype); + + /* Accept a string constant to initialize a subarray. */ + if (value != 0 + && eltcode == ARRAY_TYPE + && TREE_CODE (TREE_TYPE (elttype)) == INTEGER_TYPE + && string_flag) + value = orig_value; + /* Otherwise, if we have come to a subaggregate, + and we don't have an element of its type, push into it. */ + else if (value != 0 && !constructor_no_implicit + && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != elttype + && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE + || eltcode == UNION_TYPE)) + { + push_init_level (1); + continue; + } + + if (constructor_max_index != 0 + && tree_int_cst_lt (constructor_max_index, constructor_index)) + { + pedwarn_init ("excess elements in array initializer%s", + " after `%s'", NULL_PTR); + break; + } + + /* Now output the actual element. + Ordinarily, output once. + If there is a range, repeat it till we advance past the range. */ + do + { + tree tem; + + if (value) + { + push_array_bounds (TREE_INT_CST_LOW (constructor_index)); + output_init_element (value, elttype, constructor_index, 1); + RESTORE_SPELLING_DEPTH (constructor_depth); + } + + tem = size_binop (PLUS_EXPR, constructor_index, + integer_one_node); + TREE_INT_CST_LOW (constructor_index) + = TREE_INT_CST_LOW (tem); + TREE_INT_CST_HIGH (constructor_index) + = TREE_INT_CST_HIGH (tem); + + if (!value) + /* If we are doing the bookkeeping for an element that was + directly output as a constructor, + we must update constructor_unfilled_index. */ + { + TREE_INT_CST_LOW (constructor_unfilled_index) + = TREE_INT_CST_LOW (constructor_index); + TREE_INT_CST_HIGH (constructor_unfilled_index) + = TREE_INT_CST_HIGH (constructor_index); + } + } + while (! (constructor_range_end == 0 + || tree_int_cst_lt (constructor_range_end, + constructor_index))); + + break; + } + + /* Handle the sole element allowed in a braced initializer + for a scalar variable. */ + if (constructor_fields == 0) + { + pedwarn_init ("excess elements in scalar initializer%s", + " after `%s'", NULL_PTR); + break; + } + + if (value) + output_init_element (value, constructor_type, NULL_TREE, 1); + constructor_fields = 0; + break; + } + + /* If the (lexically) previous elments are not now saved, + we can discard the storage for them. */ + if (constructor_incremental && constructor_pending_elts == 0 && value != 0) + clear_momentary (); +} + +/* Expand an ASM statement with operands, handling output operands + that are not variables or INDIRECT_REFS by transforming such + cases into cases that expand_asm_operands can handle. + + Arguments are same as for expand_asm_operands. */ + +void +c_expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line) + tree string, outputs, inputs, clobbers; + int vol; + char *filename; + int line; +{ + int noutputs = list_length (outputs); + register int i; + /* o[I] is the place that output number I should be written. */ + register tree *o = (tree *) alloca (noutputs * sizeof (tree)); + register tree tail; + + if (TREE_CODE (string) == ADDR_EXPR) + string = TREE_OPERAND (string, 0); + if (TREE_CODE (string) != STRING_CST) + { + error ("asm template is not a string constant"); + return; + } + + /* Record the contents of OUTPUTS before it is modified. */ + for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) + o[i] = TREE_VALUE (tail); + + /* Perform default conversions on array and function inputs. */ + /* Don't do this for other types-- + it would screw up operands expected to be in memory. */ + for (i = 0, tail = inputs; tail; tail = TREE_CHAIN (tail), i++) + if (TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == ARRAY_TYPE + || TREE_CODE (TREE_TYPE (TREE_VALUE (tail))) == FUNCTION_TYPE) + TREE_VALUE (tail) = default_conversion (TREE_VALUE (tail)); + + /* Generate the ASM_OPERANDS insn; + store into the TREE_VALUEs of OUTPUTS some trees for + where the values were actually stored. */ + expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line); + + /* Copy all the intermediate outputs into the specified outputs. */ + for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) + { + if (o[i] != TREE_VALUE (tail)) + { + expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)), + 0, VOIDmode, 0); + free_temp_slots (); + } + /* Detect modification of read-only values. + (Otherwise done by build_modify_expr.) */ + else + { + tree type = TREE_TYPE (o[i]); + if (TYPE_READONLY (type) + || ((TREE_CODE (type) == RECORD_TYPE + || TREE_CODE (type) == UNION_TYPE) + && C_TYPE_FIELDS_READONLY (type))) + readonly_warning (o[i], "modification by `asm'"); + } + } + + /* Those MODIFY_EXPRs could do autoincrements. */ + emit_queue (); +} + +/* Expand a C `return' statement. + RETVAL is the expression for what to return, + or a null pointer for `return;' with no value. */ + +void +c_expand_return (retval) + tree retval; +{ + tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)); + + if (TREE_THIS_VOLATILE (current_function_decl)) + warning ("function declared `noreturn' has a `return' statement"); + + if (!retval) + { + current_function_returns_null = 1; + if (warn_return_type && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE) + warning ("`return' with no value, in function returning non-void"); + expand_null_return (); + } + else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE) + { + current_function_returns_null = 1; + if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE) + pedwarn ("`return' with a value, in function returning void"); + expand_return (retval); + } + else + { + tree t = convert_for_assignment (valtype, retval, "return", + NULL_TREE, NULL_TREE, 0); + tree res = DECL_RESULT (current_function_decl); + tree inner; + + if (t == error_mark_node) + return; + + inner = t = convert (TREE_TYPE (res), t); + + /* Strip any conversions, additions, and subtractions, and see if + we are returning the address of a local variable. Warn if so. */ + while (TREE_CODE (inner) == NOP_EXPR + || TREE_CODE (inner) == NON_LVALUE_EXPR + || TREE_CODE (inner) == CONVERT_EXPR + || TREE_CODE (inner) == PLUS_EXPR + || TREE_CODE (inner) == MINUS_EXPR) + inner = TREE_OPERAND (inner, 0); + + if (TREE_CODE (inner) == ADDR_EXPR) + { + inner = TREE_OPERAND (inner, 0); + + while (TREE_CODE_CLASS (TREE_CODE (inner)) == 'r') + inner = TREE_OPERAND (inner, 0); + + if (TREE_CODE (inner) == VAR_DECL + && ! DECL_EXTERNAL (inner) + && ! TREE_STATIC (inner) + && DECL_CONTEXT (inner) == current_function_decl) + warning ("function returns address of local variable"); + } + + t = build (MODIFY_EXPR, TREE_TYPE (res), res, t); + TREE_SIDE_EFFECTS (t) = 1; + expand_return (t); + current_function_returns_value = 1; + } +} + +/* Start a C switch statement, testing expression EXP. + Return EXP if it is valid, an error node otherwise. */ + +tree +c_expand_start_case (exp) + tree exp; +{ + register enum tree_code code = TREE_CODE (TREE_TYPE (exp)); + tree type = TREE_TYPE (exp); + + if (code != INTEGER_TYPE && code != ENUMERAL_TYPE && code != ERROR_MARK) + { + error ("switch quantity not an integer"); + exp = error_mark_node; + } + else + { + tree index; + type = TYPE_MAIN_VARIANT (TREE_TYPE (exp)); + + if (warn_traditional + && (type == long_integer_type_node + || type == long_unsigned_type_node)) + pedwarn ("`long' switch expression not converted to `int' in ANSI C"); + + exp = default_conversion (exp); + type = TREE_TYPE (exp); + index = get_unwidened (exp, NULL_TREE); + /* We can't strip a conversion from a signed type to an unsigned, + because if we did, int_fits_type_p would do the wrong thing + when checking case values for being in range, + and it's too hard to do the right thing. */ + if (TREE_UNSIGNED (TREE_TYPE (exp)) + == TREE_UNSIGNED (TREE_TYPE (index))) + exp = index; + } + + expand_start_case (1, exp, type, "switch statement"); + + return exp; +} |