From 400fbf9fdbf1661d3adfb124f2ed9d4aa6562979 Mon Sep 17 00:00:00 2001 From: Jim Wilson Date: Fri, 28 Feb 1992 10:53:39 -0800 Subject: [PATCH] Initial revision From-SVN: r364 --- gcc/c-typeck.c | 5013 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 5013 insertions(+) create mode 100644 gcc/c-typeck.c diff --git a/gcc/c-typeck.c b/gcc/c-typeck.c new file mode 100644 index 00000000000..c6de0645e08 --- /dev/null +++ b/gcc/c-typeck.c @@ -0,0 +1,5013 @@ +/* Build expressions with type checking for C compiler. + Copyright (C) 1987, 1988, 1989, 1992 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 +#include "tree.h" +#include "c-tree.h" +#include "flags.h" + +int mark_addressable (); +static tree convert_for_assignment (); +static void warn_for_assignment (); +static int function_types_compatible_p (); +static int type_lists_compatible_p (); +static int self_promoting_args_p (); +static int self_promoting_type_p (); +static int comp_target_types (); +static tree pointer_int_sum (); +static tree pointer_diff (); +static tree convert_sequence (); +static tree unary_complex_lvalue (); +static tree process_init_constructor (); +static tree convert_arguments (); +tree digest_init (); +static void pedantic_lvalue_warning (); +tree truthvalue_conversion (); +void incomplete_type_error (); +void readonly_warning (); + +/* 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. + + This is the type for the result of most arithmetic operations + if the operands have the given two types. + + We do not deal with enumeral types here because they have already been + converted to integer types. */ + +tree +common_type (t1, t2) + tree t1, t2; +{ + register enum tree_code code1; + register enum tree_code code2; + + /* 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; + + /* 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); + + 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 t1; + + if (code2 == REAL_TYPE && code1 != REAL_TYPE) + return t2; + + /* Both real or both integers; use the one with greater precision. */ + + if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2)) + return t1; + else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1)) + return t2; + + /* Same precision. Prefer longs to ints even when same size. */ + + if (t1 == long_unsigned_type_node + || t2 == long_unsigned_type_node) + return long_unsigned_type_node; + + if (t1 == long_integer_type_node + || 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)) + return long_unsigned_type_node; + return long_integer_type_node; + } + + /* Otherwise prefer the unsigned one. */ + + if (TREE_UNSIGNED (t1)) + return t1; + else return t2; + + case POINTER_TYPE: +#if 0 + /* For two pointers, do this recursively on the target type, + and combine the qualifiers of the two types' targets. */ + { + 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)); + return build_pointer_type (c_build_type_variant (target, constp, volatilep)); + } +#endif + return build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2))); + + 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 t1; + if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)) + return t2; + /* Merge the element types, and have a size if either arg has one. */ + return build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2)); + } + + 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 t1; + if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1)) + return t2; + + /* Simple way if one arg fails to specify argument types. */ + if (TYPE_ARG_TYPES (t1) == 0) + return build_function_type (valtype, TYPE_ARG_TYPES (t2)); + if (TYPE_ARG_TYPES (t2) == 0) + return build_function_type (valtype, TYPE_ARG_TYPES (t1)); + + /* 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 (0, 0, 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: ; + } + + return build_function_type (valtype, newargs); + } + + default: + return t1; + } + +} + +/* 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; + + /* 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 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); + + 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; + + /* If generating auxilliary info, allow for two different type nodes which + have essentially the same definition. */ + + if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2)) + return 1; + + switch (TREE_CODE (t1)) + { + case POINTER_TYPE: + return (TREE_TYPE (t1) == TREE_TYPE (t2) + ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2))); + + case FUNCTION_TYPE: + return function_types_compatible_p (t1, t2); + + case ARRAY_TYPE: + { + /* 1 if no need for warning yet, 2 if warning cause has been seen. */ + int val = 1; + tree d1 = TYPE_DOMAIN (t1); + tree d2 = TYPE_DOMAIN (t2); + + /* 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) + return val; + + return (((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); + } + + case RECORD_TYPE: + return maybe_objc_comptypes (t1, t2); + } + return 0; +} + +/* 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 = 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; + + 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. */ + +static 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 == float_type_node) + return 0; + + if (type + && TREE_CODE (type) == INTEGER_TYPE + && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)) + 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 == float_type_node) + return 0; + + if (TREE_CODE (type) == INTEGER_TYPE + && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)) + return 0; + + return 1; +} + +/* Return an unsigned type the same as TYPE in other respects. */ + +tree +unsigned_type (type) + tree type; +{ + if (type == signed_char_type_node || type == char_type_node) + return unsigned_char_type_node; + if (type == integer_type_node) + return unsigned_type_node; + if (type == short_integer_type_node) + return short_unsigned_type_node; + if (type == long_integer_type_node) + return long_unsigned_type_node; + if (type == 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; +{ + if (type == unsigned_char_type_node || type == char_type_node) + return signed_char_type_node; + if (type == unsigned_type_node) + return integer_type_node; + if (type == short_unsigned_type_node) + return short_integer_type_node; + if (type == long_unsigned_type_node) + return long_integer_type_node; + if (type == 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 (TREE_CODE (type) != INTEGER_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); + + 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. */ + return size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), + size_int (TYPE_PRECISION (char_type_node))); +} + +tree +c_sizeof_nowarn (type) + tree type; +{ + enum tree_code code = TREE_CODE (type); + + 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. */ + return size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), + size_int (TYPE_PRECISION (char_type_node))); +} + +/* Compute the size to increment a pointer by. */ + +tree +c_size_in_bytes (type) + tree type; +{ + enum tree_code code = TREE_CODE (type); + + 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. */ + return size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), + size_int (BITS_PER_UNIT)); +} + +/* 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) + && 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 + && TREE_READONLY (exp) + && DECL_MODE (exp) != BLKmode) + { + exp = decl_constant_value (exp); + type = TREE_TYPE (exp); + } + + /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ + if (TREE_CODE (exp) == NON_LVALUE_EXPR) + 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 && TREE_UNSIGNED (type))); + return convert (type, exp); + } + + if (code == INTEGER_TYPE + && (TYPE_PRECISION (type) + < TYPE_PRECISION (integer_type_node))) + { + /* Traditionally, unsignedness is preserved in default promotions. */ + if (flag_traditional && TREE_UNSIGNED (type)) + return convert (unsigned_type_node, exp); + return convert (integer_type_node, exp); + } + if (flag_traditional && 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; + + 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; + } + + if (TYPE_READONLY (type) || TYPE_VOLATILE (type)) + restype = c_build_type_variant (restype, TYPE_READONLY (type), + TYPE_VOLATILE (type)); + + 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; +} + +/* 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); + pedantic_lvalue_warning (COMPOUND_EXPR); + return build (COMPOUND_EXPR, TREE_TYPE (value), + TREE_OPERAND (datum, 0), value); + } + case COND_EXPR: + pedantic_lvalue_warning (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) + { + if (TYPE_SIZE (type) == 0) + { + incomplete_type_error (0, type); + return error_mark_node; + } + + /* Look up component name in the structure type definition. + + 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) + { + int cmp; + + half = (top - bot + 1) >> 1; + field = field_array[bot+half]; + cmp = (long)DECL_NAME (field) - (long)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) == component) + break; + } + } + + 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; + + 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 + && (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 (TREE_CODE (t) == VOID_TYPE + || (TYPE_SIZE (t) == 0 && TREE_CODE (t) != ARRAY_TYPE)) + { + error ("dereferencing pointer to incomplete type"); + return error_mark_node; + } + + /* We *must* set TREE_READONLY when dereferencinga 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); + 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; + + index = default_conversion (index); + if (index != error_mark_node + && TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE) + { + error ("array subscript is not an integer"); + return error_mark_node; + } + + /* 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'"); + + /* 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; + } + + if (pedantic && !lvalue_p (array)) + { + if (TREE_REGDECL (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 && TREE_REGDECL (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"); + } +} + +/* Check a printf/fprintf/sprintf/scanf/fscanf/sscanf format against PARAMS. */ + +#define ISDIGIT(c) ((c) >= '0' && (c) <= '9') + +#define T_I &integer_type_node +#define T_L &long_integer_type_node +#define T_S &short_integer_type_node +#define T_UI &unsigned_type_node +#define T_UL &long_unsigned_type_node +#define T_US &short_unsigned_type_node +#define T_F &float_type_node +#define T_D &double_type_node +#define T_LD &long_double_type_node +#define T_C &char_type_node +#define T_V &void_type_node + +typedef struct +{ + char *format_chars; + int pointer_count; + /* Type of argument if no length modifier is used. */ + tree *nolen; + /* Type of argument if length modifier for shortening is used. + If NULL, then this modifier is not allowed. */ + tree *hlen; + /* Type of argument if length modifier `l' is used. + If NULL, then this modifier is not allowed. */ + tree *llen; + /* Type of argument if length modifier `L' is used. + If NULL, then this modifier is not allowed. */ + tree *bigllen; + /* List of other modifier characters allowed with these options. */ + char *flag_chars; +} format_char_info; + +static format_char_info print_table[] + = { + { "di", 0, T_I, T_I, T_L, NULL, "-wp0 +" }, + { "oxX", 0, T_UI, T_UI, T_UL, NULL, "-wp0#" }, + { "u", 0, T_UI, T_UI, T_UL, NULL, "-wp0" }, + { "feEgG", 0, T_D, NULL, NULL, T_LD, "-wp0 +#" }, + { "c", 0, T_I, NULL, NULL, NULL, "-w" }, + { "s", 1, T_C, NULL, NULL, NULL, "-wp" }, + { "p", 1, T_V, NULL, NULL, NULL, "-" }, + { "n", 1, T_I, T_S, T_L, NULL, "" }, + { NULL } + }; + +static format_char_info scan_table[] + = { + { "di", 1, T_I, T_S, T_L, NULL, "*" }, + { "ouxX", 1, T_UI, T_US, T_UL, NULL, "*" }, + { "efgEG", 1, T_F, NULL, T_D, T_LD, "*" }, + { "s[c", 1, T_C, NULL, NULL, NULL, "*" }, + { "p", 2, T_V, NULL, NULL, NULL, "*" }, + { "n", 1, T_I, T_S, T_L, NULL, "" }, + { NULL } + }; + +typedef struct +{ + tree function_ident; /* identifier such as "printf" */ + int is_scan; /* TRUE if *scanf */ + int format_num; /* number of format argument */ + int first_arg_num; /* number of first arg (zero for varargs) */ +} function_info; + +static unsigned int function_info_entries = 0; +static function_info *function_info_table = NULL; + +/* Record information for argument format checking. FUNCTION_IDENT is + the identifier node for the name of the function to check (its decl + need not exist yet). IS_SCAN is true for scanf-type format checking; + false indicates printf-style format checking. FORMAT_NUM is the number + of the argument which is the format control string (starting from 1). + FIRST_ARG_NUM is the number of the first actual argument to check + against teh format string, or zero if no checking is not be done + (e.g. for varargs such as vfprintf). */ + +void +record_format_info (function_ident, is_scan, format_num, first_arg_num) + tree function_ident; + int is_scan; + int format_num; + int first_arg_num; +{ + function_info *info; + + function_info_entries++; + if (function_info_table) + function_info_table + = (function_info *) xrealloc (function_info_table, + function_info_entries * sizeof (function_info)); + else + function_info_table = (function_info *) xmalloc (sizeof (function_info)); + + info = &function_info_table[function_info_entries - 1]; + + info->function_ident = function_ident; + info->is_scan = is_scan; + info->format_num = format_num; + info->first_arg_num = first_arg_num; +} + +/* Initialize the table of functions to perform format checking on. + The ANSI functions are always checked (whether is + included or not), since it is common to call printf without + including . There shouldn't be a problem with this, + since ANSI reserves these function names whether you include the + header file or not. In any case, the checking is harmless. */ + +void +init_format_info_table () +{ + record_format_info (get_identifier ("printf"), 0, 1, 2); + record_format_info (get_identifier ("fprintf"), 0, 2, 3); + record_format_info (get_identifier ("sprintf"), 0, 2, 3); + record_format_info (get_identifier ("scanf"), 1, 1, 2); + record_format_info (get_identifier ("fscanf"), 1, 2, 3); + record_format_info (get_identifier ("sscanf"), 1, 2, 3); + record_format_info (get_identifier ("vprintf"), 0, 1, 0); + record_format_info (get_identifier ("vfprintf"), 0, 2, 0); + record_format_info (get_identifier ("vsprintf"), 0, 2, 0); +} + +static char tfaff[] = "too few arguments for format"; + +/* Don't rely on existence of strchr. */ + +static char * +my_strchr (string, c) + char *string; + int c; +{ + char *p; + for (p = string; *p; p++) + if (*p == c) + return p; + + return 0; +} + +/* Check the argument list of a call to printf, scanf, etc. + INFO points to the element of function_info_table. + PARAMS is the list of argument values. */ + +static void +check_format (info, params) + function_info *info; + tree params; +{ + int i; + int arg_num; + int suppressed, wide, precise; + int length_char; + int format_char; + int format_length; + tree format_tree; + tree cur_param; + tree cur_type; + tree wanted_type; + char *format_chars; + format_char_info *fci; + static char message[132]; + char flag_chars[8]; + + /* Skip to format argument. If the argument isn't available, there's + no work for us to do; prototype checking will catch the problem. */ + for (arg_num = 1; ; ++arg_num) + { + if (params == 0) + return; + if (arg_num == info->format_num) + break; + params = TREE_CHAIN (params); + } + format_tree = TREE_VALUE (params); + params = TREE_CHAIN (params); + if (format_tree == 0) + return; + /* We can only check the format if it's a string constant. */ + while (TREE_CODE (format_tree) == NOP_EXPR) + format_tree = TREE_OPERAND (format_tree, 0); /* strip coercion */ + if (format_tree == null_pointer_node) + { + warning ("null format string"); + return; + } + if (TREE_CODE (format_tree) != ADDR_EXPR) + return; + format_tree = TREE_OPERAND (format_tree, 0); + if (TREE_CODE (format_tree) != STRING_CST) + return; + format_chars = TREE_STRING_POINTER (format_tree); + format_length = TREE_STRING_LENGTH (format_tree); + if (format_length <= 1) + warning ("zero-length format string"); + if (format_chars[--format_length] != 0) + { + warning ("unterminated format string"); + return; + } + /* Skip to first argument to check. */ + while (arg_num + 1 < info->first_arg_num) + { + if (params == 0) + return; + params = TREE_CHAIN (params); + ++arg_num; + } + while (1) + { + if (*format_chars == 0) + { + if (format_chars - TREE_STRING_POINTER (format_tree) != format_length) + warning ("embedded `\\0' in format"); + if (info->first_arg_num != 0 && params != 0) + warning ("too many arguments for format"); + return; + } + if (*format_chars++ != '%') + continue; + if (*format_chars == 0) + { + warning ("spurious trailing `%%' in format"); + continue; + } + if (*format_chars == '%') + { + ++format_chars; + continue; + } + flag_chars[0] = 0; + suppressed = wide = precise = FALSE; + if (info->is_scan) + { + suppressed = *format_chars == '*'; + if (suppressed) + ++format_chars; + while (ISDIGIT (*format_chars)) + ++format_chars; + } + else + { + while (*format_chars != 0 && my_strchr (" +#0-", *format_chars) != 0) + { + if (my_strchr (flag_chars, *format_chars) != 0) + { + sprintf (message, "repeated `%c' flag in format", + *format_chars); + warning (message); + } + i = strlen (flag_chars); + flag_chars[i++] = *format_chars++; + flag_chars[i] = 0; + } + /* "If the space and + flags both appear, + the space flag will be ignored." */ + if (my_strchr (flag_chars, ' ') != 0 + && my_strchr (flag_chars, '+') != 0) + warning ("use of both ` ' and `+' flags in format"); + /* "If the 0 and - flags both appear, + the 0 flag will be ignored." */ + if (my_strchr (flag_chars, '0') != 0 + && my_strchr (flag_chars, '-') != 0) + warning ("use of both `0' and `-' flags in format"); + if (*format_chars == '*') + { + wide = TRUE; + /* "...a field width...may be indicated by an asterisk. + In this case, an int argument supplies the field width..." */ + ++format_chars; + if (params == 0) + { + warning (tfaff); + return; + } + if (info->first_arg_num != 0) + { + cur_param = TREE_VALUE (params); + params = TREE_CHAIN (params); + ++arg_num; + if (TREE_TYPE (cur_param) != integer_type_node) + { + sprintf (message, + "field width is not type int (arg %d)", + arg_num); + warning (message); + } + } + } + else + { + while (ISDIGIT (*format_chars)) + { + wide = TRUE; + ++format_chars; + } + } + if (*format_chars == '.') + { + precise = TRUE; + /* "For d, i, o, u, x, and X conversions, + if a precision is specified, the 0 flag will be ignored. + For other conversions, the behavior is undefined." */ + if (my_strchr (flag_chars, '0') != 0) + warning ("precision and `0' flag both used in one %%-sequence"); + ++format_chars; + if (*format_chars != '*' && !ISDIGIT (*format_chars)) + warning ("`.' not followed by `*' or digit in format"); + /* "...a...precision...may be indicated by an asterisk. + In this case, an int argument supplies the...precision." */ + if (*format_chars == '*') + { + if (info->first_arg_num != 0) + { + ++format_chars; + if (params == 0) + { + warning (tfaff); + return; + } + cur_param = TREE_VALUE (params); + params = TREE_CHAIN (params); + ++arg_num; + if (TREE_TYPE (cur_param) != integer_type_node) + { + sprintf (message, + "field width is not type int (arg %d)", + arg_num); + warning (message); + } + } + } + else + { + while (ISDIGIT (*format_chars)) + ++format_chars; + } + } + } + if (*format_chars == 'h' || *format_chars == 'l' || *format_chars == 'L') + length_char = *format_chars++; + else + length_char = 0; + if (suppressed && length_char != 0) + { + sprintf (message, + "use of `*' and `%c' together in format", + length_char); + warning (message); + } + format_char = *format_chars; + if (format_char == 0) + { + warning ("conversion lacks type at end of format"); + continue; + } + format_chars++; + fci = info->is_scan ? scan_table : print_table; + while (1) + { + if (fci->format_chars == 0 + || my_strchr (fci->format_chars, format_char) != 0) + break; + ++fci; + } + if (fci->format_chars == 0) + { + if (format_char >= 040 && format_char <= 0177) + sprintf (message, + "unknown conversion type character `%c' in format", + format_char); + else + sprintf (message, + "unknown conversion type character 0x%x in format", + format_char); + warning (message); + continue; + } + if (wide && my_strchr (fci->flag_chars, 'w') == 0) + { + sprintf (message, "width used with `%c' format", + format_char); + warning (message); + } + if (precise && my_strchr (fci->flag_chars, 'p') == 0) + { + sprintf (message, "precision used with `%c' format", + format_char); + warning (message); + } + if (suppressed) + { + if (my_strchr (fci->flag_chars, '*') == 0) + { + sprintf (message, + "suppression of `%c' conversion in format", + format_char); + warning (message); + } + continue; + } + for (i = 0; flag_chars[i] != 0; ++i) + { + if (my_strchr (fci->flag_chars, flag_chars[i]) == 0) + { + sprintf (message, "flag `%c' used with type `%c'", + flag_chars[i], format_char); + warning (message); + } + } + switch (length_char) + { + default: wanted_type = fci->nolen ? *(fci->nolen) : 0; break; + case 'h': wanted_type = fci->hlen ? *(fci->hlen) : 0; break; + case 'l': wanted_type = fci->llen ? *(fci->llen) : 0; break; + case 'L': wanted_type = fci->bigllen ? *(fci->bigllen) : 0; break; + } + if (wanted_type == 0) + { + sprintf (message, + "use of `%c' length character with `%c' type character", + length_char, format_char); + warning (message); + } + + /* + ** XXX -- should kvetch about stuff such as + ** { + ** const int i; + ** + ** scanf ("%d", &i); + ** } + */ + + /* Finally. . .check type of argument against desired type! */ + if (info->first_arg_num == 0) + continue; + if (params == 0) + { + warning (tfaff); + return; + } + cur_param = TREE_VALUE (params); + params = TREE_CHAIN (params); + ++arg_num; + cur_type = TREE_TYPE (cur_param); + + /* Check the types of any additional pointer arguments + that precede the "real" argument. */ + for (i = 0; i < fci->pointer_count; ++i) + { + if (TREE_CODE (cur_type) == POINTER_TYPE) + { + cur_type = TREE_TYPE (cur_type); + continue; + } + sprintf (message, + "format argument is not a %s (arg %d)", + ((fci->pointer_count == 1) ? "pointer" : "pointer to a pointer"), + arg_num); + warning (message); + break; + } + + /* Check the type of the "real" argument, if there's a type we want. */ + if (i == fci->pointer_count && wanted_type != 0 + && wanted_type != cur_type + /* Don't warn about differences merely in signedness. */ + && !(TREE_CODE (wanted_type) == INTEGER_TYPE + && TREE_CODE (cur_type) == INTEGER_TYPE + && TYPE_PRECISION (wanted_type) == TYPE_PRECISION (cur_type))) + { + register char *this; + register char *that; + + this = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (wanted_type))); + that = 0; + if (TYPE_NAME (cur_type) != 0) + if (DECL_NAME (TYPE_NAME (cur_type)) != 0) + that = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (cur_type))); + + /* A nameless type can't possibly match what the format wants. + So there will be a warning for it. + Make up a string to describe vaguely what it is. */ + if (that == 0) + { + if (TREE_CODE (cur_type) == POINTER_TYPE) + that = "pointer"; + else + that = "different type"; + } + + if (strcmp (this, that) != 0) + { + sprintf (message, "%s format, %s arg (arg %d)", + this, that, arg_num); + warning (message); + } + } + } +} + +/* 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; + register tree coerced_params; + tree name = NULL_TREE; + + /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ + if (TREE_CODE (function) == NON_LVALUE_EXPR) + function = TREE_OPERAND (function, 0); + + /* Convert anything with function type to a pointer-to-function. */ + if (TREE_CODE (function) == FUNCTION_DECL) + { + name = DECL_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)); + 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); + + /* Check for errors in format strings. */ + if (warn_format && name != 0) + { + unsigned int i; + + /* See if this function is a format function. */ + for (i = 0; i < function_info_entries; i++) + if (function_info_table[i].function_ident == name) + { + register char *message; + + /* If so, check it. */ + check_format (&function_info_table[i], coerced_params); + break; + } + } + + /* 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) + tree typelist, values, name; +{ + 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. */ + 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 + { + tree parmname; +#ifdef PROMOTE_PROTOTYPES + /* Rather than truncating and then reextending, + convert directly to int, if that's the type we will want. */ + if (! flag_traditional + && TREE_CODE (type) == INTEGER_TYPE + && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) + type = integer_type_node; +#endif + +#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 can overflow. */ + if (warn_conversion) + { + int formal_prec = TYPE_PRECISION (type); + int actual_prec = TYPE_PRECISION (TREE_TYPE (val)); + int int_prec = TYPE_PRECISION (integer_type_node); + + if (TREE_CODE (type) != REAL_TYPE + && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) + warning ("floating argument converted to integer"); + else if (TREE_CODE (type) == REAL_TYPE + && TREE_CODE (TREE_TYPE (val)) != REAL_TYPE) + warning ("integer argument converted to floating"); + /* 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_UNSIGNED (type) + != TREE_UNSIGNED (TREE_TYPE (val))) + || (MAX (formal_prec, int_prec) + != MAX (actual_prec, int_prec)))) + { + if (MAX (formal_prec, int_prec) + != MAX (actual_prec, int_prec)) + warning ("integer argument converted in width"); + 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. */ + ; + else if (TREE_UNSIGNED (type)) + warning ("signed argument converted to unsigned"); + else + warning ("unsigned argument converted to signed"); + } + } + + parmval = convert_for_assignment (type, val, + (char *)0, /* arg passing */ + name, parmnum + 1); + +#ifdef PROMOTE_PROTOTYPES + if (TREE_CODE (type) == INTEGER_TYPE + && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) + parmval = default_conversion (parmval); +#endif + } + result = tree_cons (0, 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< 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: + if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) + shorten = 1; + break; + + case TRUTH_ANDIF_EXPR: + case TRUTH_ORIF_EXPR: + case TRUTH_AND_EXPR: + case TRUTH_OR_EXPR: + if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE || code0 == REAL_TYPE) + && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE || code1 == REAL_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_LOW (op1) > 0) + short_shift = 1; + else if (TREE_INT_CST_LOW (op1) < 0) + warning ("shift count is negative"); + if (TREE_INT_CST_LOW (op1) >= TYPE_PRECISION (type0)) + warning ("shift count exceeds width of value shifted"); + } + /* Unless traditional, convert the shift-count to an integer, + regardless of size of value being shifted. */ + if (! flag_traditional) + { + result_type = type0; + if (TREE_TYPE (op1) != integer_type_node) + op1 = convert (integer_type_node, op1); + /* Avoid converting op1 to result_type later. */ + converted = 1; + } + else + common = 1; + } + break; + + case LSHIFT_EXPR: + if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) + { + if (TREE_CODE (op1) == INTEGER_CST + && TREE_INT_CST_LOW (op1) < 0) + warning ("shift count is negative"); + if (TREE_CODE (op1) == INTEGER_CST + && TREE_INT_CST_LOW (op1) >= TYPE_PRECISION (type0)) + warning ("shift count exceeds width of value shifted"); + /* Unless traditional, convert the shift-count to an integer, + regardless of size of value being shifted. */ + if (! flag_traditional) + { + result_type = type0; + if (TREE_TYPE (op1) != integer_type_node) + op1 = convert (integer_type_node, op1); + /* Avoid converting op1 to result_type later. */ + converted = 1; + } + else + common = 1; + } + break; + + case RROTATE_EXPR: + case LROTATE_EXPR: + if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) + { + if (TREE_CODE (op1) == INTEGER_CST + && TREE_INT_CST_LOW (op1) < 0) + warning ("shift count is negative"); + if (TREE_CODE (op1) == INTEGER_CST + && TREE_INT_CST_LOW (op1) >= TYPE_PRECISION (type0)) + warning ("shift count >= width of value shifted"); + /* Unless traditional, convert the shift-count to an integer, + regardless of size of value being shifted. */ + if (! flag_traditional) + { + result_type = type0; + if (TREE_TYPE (op1) != integer_type_node) + op1 = convert (integer_type_node, op1); + /* Avoid converting op1 to result_type later. */ + converted = 1; + } + else + common = 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) + && (code1 == INTEGER_TYPE || code1 == REAL_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 the same. */ + if (comp_target_types (type0, type1)) + ; + else if (TYPE_MAIN_VARIANT (tt0) == void_type_node) + { + if (pedantic && !integer_zerop (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) + && 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 (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 (! flag_traditional) + 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) + && (code1 == INTEGER_TYPE || code1 == REAL_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) + { + 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 does not *contain* a conversion + but it *requires* conversion to FINAL_TYPE. */ + + if (op0 == arg0 && TREE_TYPE (op0) != final_type) + unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0)); + if (op1 == 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; + if (TREE_CODE (intop) == MINUS_EXPR) + subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR); + ptrop = build_binary_op (subcode, ptrop, TREE_OPERAND (intop, 1), 1); + intop = 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. */ + + intop = build_binary_op (MULT_EXPR, 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); + op1 = c_size_in_bytes (target_type); + + /* Divide by the size, in easiest possible way. */ + + result = build (EXACT_DIV_EXPR, restype, op0, 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)) + 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)) + errstring = "wrong type argument to unary minus"; + else if (!noconvert) + arg = default_conversion (arg); + break; + + case BIT_NOT_EXPR: + 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)) + errstring = "wrong type argument to abs"; + else if (!noconvert) + arg = default_conversion (arg); + break; + + case TRUTH_NOT_EXPR: + if (typecode != INTEGER_TYPE + && typecode != REAL_TYPE && typecode != POINTER_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 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; + + /* 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 (pedantic + && (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: + /* 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; + pedantic_lvalue_warning (CONVERT_EXPR); + 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 (TYPE_READONLY (TREE_TYPE (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 + function counts as a constant */ + TREE_CONSTANT (addr) = staticp (arg); + 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 TREE_REGDECL. */ + +int +lvalue_p (ref) + tree ref; +{ + register enum tree_code code = TREE_CODE (ref); + + switch (code) + { + 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); + + 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: + 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 (TREE_REGDECL (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; + + /* 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 (TREE_CODE (ifexp) == ERROR_MARK + || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK + || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK) + return error_mark_node; + +#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 (integer_zerop (ifexp) ? op2 : op1); + + return fold (build (COND_EXPR, TREE_TYPE (op1), ifexp, op1, op2)); + } +#endif + + /* They don't match; promote them both and then try to reconcile them. */ + + if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE) + op1 = default_conversion (op1); + if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE) + op2 = default_conversion (op2); + + 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 (type1 == type2) + result_type = 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) + result_type = qualify_type (type2, type1); + else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node) + 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; + } + } + + if (result_type != TREE_TYPE (op1)) + op1 = convert (result_type, op1); + if (result_type != TREE_TYPE (op2)) + op2 = convert (result_type, op2); + +#if 0 + if (code1 == RECORD_TYPE || code1 == UNION_TYPE) + { + result_type = TREE_TYPE (op1); + if (TREE_CONSTANT (ifexp)) + return (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 (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; +{ + register tree rest; + + if (TREE_CHAIN (list) == 0) + { +#if 0 /* If something inside inhibited lvalueness, we shoukd 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 + + 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 = build_compound_expr (TREE_CHAIN (list)); + + if (! TREE_SIDE_EFFECTS (TREE_VALUE (list))) + 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; + 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) + { + tree nvalue = build1 (CONVERT_EXPR, type, value); + TREE_CONSTANT (nvalue) = TREE_CONSTANT (value); + if (pedantic) + pedwarn ("ANSI C forbids casts to union type"); + return nvalue; + } + error ("cast to union type from type not present in union"); + return error_mark_node; + } + else + { + tree otype; + /* 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 worrysome 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. */ +#ifdef STRICT_ALIGNMENT + if (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"); +#endif + + if (TREE_CODE (type) == INTEGER_TYPE + && TREE_CODE (otype) == POINTER_TYPE + && TYPE_PRECISION (type) != TYPE_PRECISION (otype)) + warning ("cast from pointer to integer of different size"); + + if (TREE_CODE (type) == POINTER_TYPE + && TREE_CODE (otype) == INTEGER_TYPE + && TYPE_PRECISION (type) != TYPE_PRECISION (otype)) + warning ("cast to pointer from integer of different size"); + + value = convert (type, value); + } + + if (value == expr && pedantic) + { + /* If pedantic, don't let a cast be an lvalue. */ + return 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. */ + 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); + return build (COMPOUND_EXPR, lhstype, + TREE_OPERAND (lhs, 0), + build_modify_expr (TREE_OPERAND (lhs, 1), + modifycode, rhs)); + + /* 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)); + /* 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))); + 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, 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, 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). + + 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, funname, parmnum) + tree type, rhs; + char *errtype; + tree 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. */ + 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); + + 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)) + 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) + && + (coder == INTEGER_TYPE || coder == REAL_TYPE || coder == ENUMERAL_TYPE)) + { + return convert (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) + || (!pedantic /* Unless pedantic, mix signed and unsigned. */ + && TREE_CODE (ttl) == INTEGER_TYPE + && TREE_CODE (ttr) == INTEGER_TYPE + && TYPE_PRECISION (ttl) == TYPE_PRECISION (ttr))) + { + if (pedantic + && ((TYPE_MAIN_VARIANT (ttl) == void_type_node + && TREE_CODE (ttr) == FUNCTION_TYPE) + || + (TYPE_MAIN_VARIANT (ttr) == void_type_node + && !integer_zerop (rhs) + && TREE_CODE (ttl) == FUNCTION_TYPE))) + warn_for_assignment ("ANSI forbids %s between function pointer and `void *'", + 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", + errtype, funname, parmnum); + if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr)) + warn_for_assignment ("%s discards `volatile' from pointer target type", + 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", + errtype, funname, parmnum); + if (TYPE_VOLATILE (ttl) && ! TYPE_VOLATILE (ttr)) + warn_for_assignment ("%s makes `volatile *' function pointer from non-volatile", + errtype, funname, parmnum); + } + } + else if (unsigned_type (TYPE_MAIN_VARIANT (ttl)) + == unsigned_type (TYPE_MAIN_VARIANT (ttr))) + warn_for_assignment ("pointer targets in %s differ in signedness", + errtype, funname, parmnum); + else + warn_for_assignment ("%s from incompatible pointer type", + errtype, funname, parmnum); + return convert (type, rhs); + } + else if (codel == POINTER_TYPE && coder == INTEGER_TYPE) + { + if (! integer_zerop (rhs)) + { + warn_for_assignment ("%s makes pointer from integer without a cast", + 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", + errtype, funname, parmnum); + return convert (type, rhs); + } + + if (!errtype) + { + if (funname) + 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", 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. */ + +static tree +initializer_constant_valid_p (value) + tree value; +{ + switch (TREE_CODE (value)) + { + case CONSTRUCTOR: + return TREE_STATIC (value) ? null_pointer_node : 0; + + case INTEGER_CST: + case REAL_CST: + case STRING_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)); + + 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)); + /* 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)); + /* 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 + && tree_int_cst_equal (TYPE_SIZE (TREE_TYPE (value)), + TYPE_SIZE (TREE_TYPE (TREE_OPERAND (value, 0))))) + return initializer_constant_valid_p (TREE_OPERAND (value, 0)); + /* Allow conversions between 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)); + if (inner == null_pointer_node) + return null_pointer_node; + return 0; + } + /* Allow (int) &foo. */ + if (TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE + && TREE_CODE (TREE_TYPE (TREE_OPERAND (value, 0))) == POINTER_TYPE + && tree_int_cst_equal (TYPE_SIZE (TREE_TYPE (value)), + TYPE_SIZE (TREE_TYPE (TREE_OPERAND (value, 0))))) + return initializer_constant_valid_p (TREE_OPERAND (value, 0)); + return 0; + + case PLUS_EXPR: + { + tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0)); + tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1)); + /* 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: + { + tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0)); + tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1)); + /* 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; +} + +/* 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, 0, TREE_STATIC (decl), + TREE_STATIC (decl) || pedantic, + IDENTIFIER_POINTER (DECL_NAME (decl))); + + /* 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 constuctor 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) == 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; +} + +/* 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 a null string, then LOCAL is omitted entirely. */ + +void +error_init (format, local, ofwhat) + char *format, *local, *ofwhat; +{ + char *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 a null string, then LOCAL is omitted entirely. */ + +void +pedwarn_init (format, local, ofwhat) + char *format, *local, *ofwhat; +{ + char *buffer = (char *) alloca (strlen (local) + strlen (ofwhat) + 2); + + if (*ofwhat) + sprintf (buffer, local, ofwhat); + else + buffer[0] = 0; + + pedwarn (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. + + If TAIL is nonzero, it points to a variable holding a list of elements + of which INIT is the first. We update the list stored there by + removing from the head all the elements that we use. + Normally this is only one; we use more than one element only if + TYPE is an aggregate and INIT is not a constructor. + + 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. + + If OFWHAT is nonzero, it specifies what we are initializing, for error + messages. Examples: variable name, variable.member, array[44]. */ + +tree +digest_init (type, init, tail, require_constant, constructor_constant, ofwhat) + tree type, init, *tail; + int require_constant, constructor_constant; + char *ofwhat; +{ + enum tree_code code = TREE_CODE (type); + tree element = 0; + tree old_tail_contents; + char *member_str; /* For building strings about member names. */ + /* Nonzero if INIT is a braced grouping, which comes in as a CONSTRUCTOR + tree node which has no TREE_TYPE. */ + int raw_constructor + = TREE_CODE (init) == CONSTRUCTOR && TREE_TYPE (init) == 0; + + /* By default, assume we use one element from a list. + We correct this later in the sole case where it is not true. */ + + if (tail) + { + old_tail_contents = *tail; + *tail = TREE_CHAIN (*tail); + } + + if (init == error_mark_node) + return init; + + /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ + if (TREE_CODE (init) == NON_LVALUE_EXPR) + init = TREE_OPERAND (init, 0); + + if (init && raw_constructor + && CONSTRUCTOR_ELTS (init) != 0 + && TREE_CHAIN (CONSTRUCTOR_ELTS (init)) == 0) + { + element = TREE_VALUE (CONSTRUCTOR_ELTS (init)); + /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ + if (element && TREE_CODE (element) == NON_LVALUE_EXPR) + element = TREE_OPERAND (element, 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) + && ((init && TREE_CODE (init) == STRING_CST) + || (element && TREE_CODE (element) == STRING_CST))) + { + tree string = element ? element : init; + + if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (string))) + != char_type_node) + && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node)) + { + error_init ("char-array%s initialized from wide string", + " `%s'", ofwhat); + return error_mark_node; + } + if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (string))) + == char_type_node) + && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node)) + { + error_init ("int-array%s initialized from non-wide string", + " `%s'", ofwhat); + return error_mark_node; + } + + TREE_TYPE (string) = 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 because it's ok to ignore the terminating null char + that is counted in the length of the constant. */ + if (size < TREE_STRING_LENGTH (string) - 1) + pedwarn_init ( + "initializer-string for array of chars%s is too long", + " `%s'", ofwhat); + } + return string; + } + } + + /* Any type except an array can be initialized + from an expression of the same type, optionally with braces. + For an array, this is allowed only for a string constant. */ + + if (init && (TREE_TYPE (init) == type + || (code == ARRAY_TYPE && TREE_TYPE (init) + && comptypes (TREE_TYPE (init), type)) + || (code == POINTER_TYPE + && TREE_TYPE (init) != 0 + && (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE + || TREE_CODE (TREE_TYPE (init)) == FUNCTION_TYPE) + && comptypes (TREE_TYPE (TREE_TYPE (init)), + TREE_TYPE (type))))) + { + if (code == POINTER_TYPE + && (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE + || TREE_CODE (TREE_TYPE (init)) == FUNCTION_TYPE)) + init = default_conversion (init); + else if (code == ARRAY_TYPE && TREE_CODE (init) != STRING_CST) + { + error_init ("array%s initialized from non-constant array expression", + " `%s'", ofwhat); + return error_mark_node; + } + + if (optimize && TREE_READONLY (init) && TREE_CODE (init) == VAR_DECL) + init = decl_constant_value (init); + + if (require_constant && ! TREE_CONSTANT (init)) + { + error_init ("initializer element%s is not constant", + " for `%s'", ofwhat); + init = error_mark_node; + } + else if (require_constant && initializer_constant_valid_p (init) == 0) + { + error_init ("initializer element%s is not computable at load time", + " for `%s'", ofwhat); + init = error_mark_node; + } + + return init; + } + + if (element && (TREE_TYPE (element) == type + || (code == ARRAY_TYPE && TREE_TYPE (element) + && comptypes (TREE_TYPE (element), type)))) + { + if (code == ARRAY_TYPE) + { + error_init ("array%s initialized from non-constant array expression", + " `%s'", ofwhat); + return error_mark_node; + } + if (pedantic && (code == RECORD_TYPE || code == UNION_TYPE)) + pedwarn ("single-expression nonscalar initializer has braces"); + if (optimize && TREE_READONLY (element) && TREE_CODE (element) == VAR_DECL) + element = decl_constant_value (element); + + if (require_constant && ! TREE_CONSTANT (element)) + { + error_init ("initializer element%s is not constant", + " for `%s'", ofwhat); + element = error_mark_node; + } + else if (require_constant && initializer_constant_valid_p (element) == 0) + { + error_init ("initializer element%s is not computable at load time", + " for `%s'", ofwhat); + element = error_mark_node; + } + + return element; + } + + /* Check for initializing a union by its first field. + Such an initializer must use braces. */ + + if (code == UNION_TYPE) + { + tree result; + tree field = TYPE_FIELDS (type); + + /* Find the first named field. ANSI decided in September 1990 + that only named fields count here. */ + while (field && DECL_NAME (field) == 0) + field = TREE_CHAIN (field); + + if (field == 0) + { + error_init ("union%s with no named members cannot be initialized", + " `%s'", ofwhat); + return error_mark_node; + } + + /* Build the name of this member, with a "." for membership. */ + member_str = (char *) alloca (strlen (ofwhat) + + IDENTIFIER_LENGTH (DECL_NAME (field)) + 2); + sprintf (member_str, "%s.%s", ofwhat, + IDENTIFIER_POINTER (DECL_NAME (field))); + + if (raw_constructor) + return process_init_constructor (type, init, 0, + require_constant, + constructor_constant, member_str); + else if (tail != 0) + { + *tail = old_tail_contents; + return process_init_constructor (type, 0, tail, + require_constant, + constructor_constant, member_str); + } + } + + /* Handle scalar types, including conversions. */ + + if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE + || code == ENUMERAL_TYPE) + { + if (raw_constructor) + { + if (element == 0) + { + error_init ( + "initializer for scalar%s requires one element", + " `%s'", ofwhat); + return error_mark_node; + } + init = element; + } + +#if 0 /* A non-raw constructor is an actual expression. */ + if (TREE_CODE (init) == CONSTRUCTOR) + { + error_init ("initializer for scalar%s has extra braces", + " `%s'", ofwhat); + return error_mark_node; + } +#endif + + /* Build the name of the member being initialized, for error msgs. */ + { + /* Avoid counting chars */ + static char message[] = "initialization of `%s'"; + member_str = (char *) alloca (strlen (ofwhat) + sizeof (message) + 1); + sprintf (member_str, message, ofwhat); + } + + init = convert_for_assignment (type, default_conversion (init), + member_str, NULL_TREE, 0); + + if (require_constant && ! TREE_CONSTANT (init)) + { + error_init ("initializer element%s is not constant", + " for `%s'", ofwhat); + init = error_mark_node; + } + else if (require_constant && initializer_constant_valid_p (init) == 0) + { + error_init ("initializer element%s is not computable at load time", + " for `%s'", ofwhat); + init = error_mark_node; + } + + return 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'", ofwhat); + return error_mark_node; + } + + if (code == ARRAY_TYPE || code == RECORD_TYPE) + { + if (raw_constructor) + return process_init_constructor (type, init, 0, constructor_constant, + constructor_constant, ofwhat); + else if (tail != 0) + { + *tail = old_tail_contents; + return process_init_constructor (type, 0, tail, constructor_constant, + constructor_constant, ofwhat); + } + else if (flag_traditional) + /* Traditionally one can say `char x[100] = 0;'. */ + return process_init_constructor (type, + build_nt (CONSTRUCTOR, 0, + tree_cons (0, init, 0)), + 0, constructor_constant, + constructor_constant, ofwhat); + } + + error_init ("invalid initializer%s", " for `%s'", ofwhat); + return error_mark_node; +} + +/* Process a constructor for a variable of type TYPE. + The constructor elements may be specified either with INIT or with ELTS, + only one of which should be non-null. + + If INIT is specified, it is a CONSTRUCTOR node which is specifically + and solely for initializing this datum. + + If ELTS is specified, it is the address of a variable containing + a list of expressions. We take as many elements as we need + from the head of the list and update the list. + + In the resulting constructor, TREE_CONSTANT is set if all elts are + constant, and TREE_STATIC is set if, in addition, all elts are simple enough + constants that the assembler and linker can compute them. + + The argument CONSTANT_VALUE says to print an error if either the + value or any element is not a constant. + + The argument CONSTANT_ELEMENT says to print an error if an element + of an aggregate is not constant. It does not apply to a value + which is not a constructor. + + OFWHAT is a character string describing the object being initialized, + for error messages. It might be "variable" or "variable.member" + or "variable[17].member[5]". */ + +static tree +process_init_constructor (type, init, elts, constant_value, constant_element, + ofwhat) + tree type, init, *elts; + int constant_value, constant_element; + char *ofwhat; +{ + register tree tail; + /* List of the elements of the result constructor, + in reverse order. */ + register tree members = NULL; + int members_length = 0; + tree result; + int allconstant = 1; + int allsimple = 1; + int erroneous = 0; + char *member_str; /* String used to pass member names. */ + + /* Make TAIL be the list of elements to use for the initialization, + no matter how the data was given to us. */ + + if (elts) + tail = *elts; + else + tail = CONSTRUCTOR_ELTS (init); + + /* Gobble as many elements as needed, and make a constructor or initial value + for each element of this aggregate. Chain them together in result. + If there are too few, use 0 for each scalar ultimate component. */ + + if (TREE_CODE (type) == ARRAY_TYPE) + { + tree domain = TYPE_DOMAIN (type); + register long len; + register int i; + + if (domain) + len = (TREE_INT_CST_LOW (TYPE_MAX_VALUE (domain)) + - TREE_INT_CST_LOW (TYPE_MIN_VALUE (domain)) + + 1); + else + len = -1; /* Take as many as there are */ + + /* Don't leave the loop based on i if the next item has an explicit + index value that will override i. */ + + for (i = 0; tail != 0; i++) + { + register tree next1; + + /* If this element specifies an index, + move to that index before storing it in the new list. */ + if (TREE_PURPOSE (tail) != 0) + { + int win = 0; + + if (TREE_CODE (TREE_PURPOSE (tail)) == IDENTIFIER_NODE) + error ("field name used as index in array initializer"); + else if (TREE_CODE (TREE_PURPOSE (tail)) != INTEGER_CST) + error ("non-constant array index in initializer"); + else if (domain != 0 + && (tree_int_cst_lt (TREE_PURPOSE (tail), + TYPE_MIN_VALUE (domain)) + || tree_int_cst_lt (TYPE_MAX_VALUE (domain), + TREE_PURPOSE (tail)))) + error ("array index out of range in initializer"); + else + i = TREE_INT_CST_LOW (TREE_PURPOSE (tail)), win = 1; + + if (!win) + TREE_VALUE (tail) = error_mark_node; + } + + if (len >= 0 && i >= len) + break; /* Stop if we've indeed run out of elements. */ + + /* Now digest the value specified. */ + if (TREE_VALUE (tail) != 0) + { + tree tail1 = tail; + + /* Build the index of this member, with a "." for membership. */ + member_str = (char *) alloca (25 + strlen (ofwhat)); + sprintf (member_str, "%s[%d]", ofwhat, i); + + next1 = digest_init (TYPE_MAIN_VARIANT (TREE_TYPE (type)), + TREE_VALUE (tail), &tail1, + /* Both of these are the same because + a value here is an elt overall. */ + constant_element, constant_element, + member_str); + + if (tail1 != 0 && TREE_CODE (tail1) != TREE_LIST) + abort (); + if (tail == tail1 && len < 0) + { + error_init ( + "non-empty initializer for array%s of empty elements", + " `%s'", ofwhat); + /* Just ignore what we were supposed to use. */ + tail1 = 0; + } + tail = tail1; + } + else + { + next1 = error_mark_node; + tail = TREE_CHAIN (tail); + } + + if (next1 == error_mark_node) + erroneous = 1; + else if (!TREE_CONSTANT (next1)) + allconstant = 0; + else if (initializer_constant_valid_p (next1) == 0) + allsimple = 0; + + /* Now store NEXT1 in the list, I elements from the *end*. + Make the list longer if necessary. */ + while (i >= members_length) + { + members = tree_cons (NULL_TREE, NULL_TREE, members); + members_length++; + } + { + tree temp; + int j; + + temp = members; + for (j = members_length - 1; j > i; j--) + temp = TREE_CHAIN (temp); + TREE_VALUE (temp) = next1; + } + } + } + if (TREE_CODE (type) == RECORD_TYPE) + { + register tree field; + int i; + + /* Don't leave the loop based on field just yet; see if next item + overrides the expected field first. */ + + for (field = TYPE_FIELDS (type), i = 0; tail; + field = TREE_CHAIN (field), i++) + { + register tree next1; + + /* If this element specifies a field, + move to that field before storing it in the new list. */ + if (TREE_PURPOSE (tail) != 0) + { + int win = 0; + + if (TREE_CODE (TREE_PURPOSE (tail)) != IDENTIFIER_NODE) + error ("index value instead of field name in structure initializer"); + else + { + tree temp; + int j; + for (temp = TYPE_FIELDS (type), j = 0; + temp; + temp = TREE_CHAIN (temp), j++) + if (DECL_NAME (temp) == TREE_PURPOSE (tail)) + break; + if (temp) + field = temp, i = j, win = 1; + else + error_with_decl (temp, "no field `%s' in structure being initialized"); + } + if (!win) + TREE_VALUE (tail) = error_mark_node; + } + + if (field == 0) + break; /* No more fields to init. */ + + if (! DECL_NAME (field)) + { + next1 = integer_zero_node; + } + else if (TREE_VALUE (tail) != 0) + { + tree tail1 = tail; + + /* Build the name of this member, with a "." for membership. */ + member_str = (char *) alloca (strlen (ofwhat) + + IDENTIFIER_LENGTH (DECL_NAME (field)) + 2); + sprintf (member_str, "%s.%s", ofwhat, + IDENTIFIER_POINTER (DECL_NAME (field))); + + next1 = digest_init (TREE_TYPE (field), + TREE_VALUE (tail), &tail1, + constant_element, constant_element, + member_str); + if (tail1 != 0 && TREE_CODE (tail1) != TREE_LIST) + abort (); + tail = tail1; + } + else + { + next1 = error_mark_node; + tail = TREE_CHAIN (tail); + } + + if (next1 == error_mark_node) + erroneous = 1; + else if (!TREE_CONSTANT (next1)) + allconstant = 0; + else if (initializer_constant_valid_p (next1) == 0) + allsimple = 0; + + /* Now store NEXT1 in the list, I elements from the *end*. + Make the list longer if necessary. */ + while (i >= members_length) + { + members = tree_cons (NULL_TREE, NULL_TREE, members); + members_length++; + } + { + tree temp; + int j; + + temp = members; + for (j = members_length - 1; j > i; j--) + temp = TREE_CHAIN (temp); + TREE_VALUE (temp) = next1; + TREE_PURPOSE (temp) = field; + } + } + } + if (TREE_CODE (type) == UNION_TYPE) + { + register tree field = TYPE_FIELDS (type); + register tree next1; + + /* Find the first named field. ANSI decided in September 1990 + that only named fields count here. */ + while (field && DECL_NAME (field) == 0) + field = TREE_CHAIN (field); + + /* For a union, get the initializer for 1 fld. */ + + /* If this element specifies a field, initialize via that field. */ + if (TREE_PURPOSE (tail) != 0) + { + int win = 0; + + if (TREE_CODE (TREE_PURPOSE (tail)) != IDENTIFIER_NODE) + error ("index value instead of field name in union initializer"); + else + { + tree temp; + for (temp = TYPE_FIELDS (type); + temp; + temp = TREE_CHAIN (temp)) + if (DECL_NAME (temp) == TREE_PURPOSE (tail)) + break; + if (temp) + field = temp, win = 1; + else + error_with_decl (temp, "no field `%s' in union being initialized"); + } + if (!win) + TREE_VALUE (tail) = error_mark_node; + } + + if (TREE_VALUE (tail) != 0) + { + tree tail1 = tail; + + /* Build the name of this member, with a "." for membership. */ + member_str = (char *) alloca (strlen (ofwhat) + + IDENTIFIER_LENGTH (DECL_NAME (field)) + 2); + sprintf (member_str, "%s.%s", ofwhat, + IDENTIFIER_POINTER (DECL_NAME (field))); + + next1 = digest_init (TREE_TYPE (field), + TREE_VALUE (tail), &tail1, + constant_value, constant_element, member_str); + if (tail1 != 0 && TREE_CODE (tail1) != TREE_LIST) + abort (); + tail = tail1; + } + else + { + next1 = error_mark_node; + tail = TREE_CHAIN (tail); + } + + if (next1 == error_mark_node) + erroneous = 1; + else if (!TREE_CONSTANT (next1)) + allconstant = 0; + else if (initializer_constant_valid_p (next1) == 0) + allsimple = 0; + members = tree_cons (field, next1, members); + } + + /* If arguments were specified as a list, just remove the ones we used. */ + if (elts) + *elts = tail; + /* If arguments were specified as a constructor, + complain unless we used all the elements of the constructor. */ + else if (tail) + { + if (TREE_CODE (type) == UNION_TYPE) + { + pedwarn_init ("excess elements in union initializer%s", + " after `%s'", ofwhat); + } + else + { + pedwarn_init ("excess elements in aggregate initializer%s", + " after `%s'", ofwhat); + } + } + + if (erroneous) + return error_mark_node; + + result = build (CONSTRUCTOR, type, NULL_TREE, nreverse (members)); + if (allconstant) TREE_CONSTANT (result) = 1; + if (allconstant && allsimple) TREE_STATIC (result) = 1; + return result; +} + +/* 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 modifed. */ + 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 `volatile' 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, 0); + tree res = DECL_RESULT (current_function_decl); + t = build (MODIFY_EXPR, TREE_TYPE (res), + res, convert (TREE_TYPE (res), t)); + 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; + + if (warn_traditional + && (TREE_TYPE (exp) == long_integer_type_node + || TREE_TYPE (exp) == 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, 0); + /* 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; +} -- 2.30.2