--- /dev/null
+/* 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 <stdio.h>
+#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 ();
+\f
+/* 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);
+}
+\f
+/* 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;
+ }
+
+}
+\f
+/* 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;
+}
+\f
+/* 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;
+}
+\f
+/* 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);
+}
+\f
+/* 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;
+}
+\f
+/* 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;
+}
+\f
+/* 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");
+ }
+}
+\f
+/* 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 <stdio.h> is
+ included or not), since it is common to call printf without
+ including <stdio.h>. 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;
+}
+\f
+/* 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);
+ }
+ }
+ }
+}
+\f
+/* 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);
+ }
+}
+\f
+/* 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);
+}
+\f
+/* This is the entry point used by the parser
+ for binary operators in the input.
+ In addition to constructing the expression,
+ we check for operands that were written with other binary operators
+ in a way that is likely to confuse the user. */
+
+tree
+parser_build_binary_op (code, arg1, arg2)
+ enum tree_code code;
+ tree arg1, arg2;
+{
+ tree result = build_binary_op (code, arg1, arg2, 1);
+
+ char class;
+ char class1 = TREE_CODE_CLASS (TREE_CODE (arg1));
+ char class2 = TREE_CODE_CLASS (TREE_CODE (arg2));
+ enum tree_code code1 = ERROR_MARK;
+ enum tree_code code2 = ERROR_MARK;
+
+ if (class1 == 'e' || class1 == '1'
+ || class1 == '2' || class1 == '<')
+ code1 = C_EXP_ORIGINAL_CODE (arg1);
+ if (class2 == 'e' || class2 == '1'
+ || class2 == '2' || class2 == '<')
+ code2 = C_EXP_ORIGINAL_CODE (arg2);
+
+ /* Check for cases such as x+y<<z which users are likely
+ to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
+ is cleared to prevent these warnings. */
+ if (warn_parentheses)
+ {
+ if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
+ {
+ if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
+ || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
+ warning ("suggest parentheses around + or - inside shift");
+ }
+
+ if (code == TRUTH_ORIF_EXPR)
+ {
+ if (code1 == TRUTH_ANDIF_EXPR
+ || code2 == TRUTH_ANDIF_EXPR)
+ warning ("suggest parentheses around && within ||");
+ }
+
+ if (code == BIT_IOR_EXPR)
+ {
+ if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
+ || code1 == PLUS_EXPR || code1 == MINUS_EXPR
+ || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
+ || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
+ warning ("suggest parentheses around arithmetic in operand of |");
+ }
+
+ if (code == BIT_XOR_EXPR)
+ {
+ if (code1 == BIT_AND_EXPR
+ || code1 == PLUS_EXPR || code1 == MINUS_EXPR
+ || code2 == BIT_AND_EXPR
+ || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
+ warning ("suggest parentheses around arithmetic in operand of ^");
+ }
+
+ if (code == BIT_AND_EXPR)
+ {
+ if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
+ || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
+ warning ("suggest parentheses around + or - in operand of &");
+ }
+ }
+
+ class = TREE_CODE_CLASS (TREE_CODE (result));
+
+ /* Record the code that was specified in the source,
+ for the sake of warnings about confusing nesting. */
+ if (class == 'e' || class == '1'
+ || class == '2' || class == '<')
+ C_SET_EXP_ORIGINAL_CODE (result, code);
+ else
+ {
+ int flag = TREE_CONSTANT (result);
+ result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
+ C_SET_EXP_ORIGINAL_CODE (result, code);
+ TREE_CONSTANT (result) = flag;
+ }
+
+ return result;
+}
+
+/* Build a binary-operation expression without default conversions.
+ CODE is the kind of expression to build.
+ This function differs from `build' in several ways:
+ the data type of the result is computed and recorded in it,
+ warnings are generated if arg data types are invalid,
+ special handling for addition and subtraction of pointers is known,
+ and some optimization is done (operations on narrow ints
+ are done in the narrower type when that gives the same result).
+ Constant folding is also done before the result is returned.
+
+ Note that the operands will never have enumeral types, or function
+ or array types, because either they will have the default conversions
+ performed or they have both just been converted to some other type in which
+ the arithmetic is to be done. */
+
+tree
+build_binary_op (code, orig_op0, orig_op1, convert_p)
+ enum tree_code code;
+ tree orig_op0, orig_op1;
+ int convert_p;
+{
+ tree type0, type1;
+ register enum tree_code code0, code1;
+ tree op0, op1;
+
+ /* Expression code to give to the expression when it is built.
+ Normally this is CODE, which is what the caller asked for,
+ but in some special cases we change it. */
+ register enum tree_code resultcode = code;
+
+ /* Data type in which the computation is to be performed.
+ In the simplest cases this is the common type of the arguments. */
+ register tree result_type = NULL;
+
+ /* Nonzero means operands have already been type-converted
+ in whatever way is necessary.
+ Zero means they need to be converted to RESULT_TYPE. */
+ int converted = 0;
+
+ /* Nonzero means after finally constructing the expression
+ give it this type. Otherwise, give it type RESULT_TYPE. */
+ tree final_type = 0;
+
+ /* Nonzero if this is an operation like MIN or MAX which can
+ safely be computed in short if both args are promoted shorts.
+ Also implies COMMON.
+ -1 indicates a bitwise operation; this makes a difference
+ in the exact conditions for when it is safe to do the operation
+ in a narrower mode. */
+ int shorten = 0;
+
+ /* Nonzero if this is a comparison operation;
+ if both args are promoted shorts, compare the original shorts.
+ Also implies COMMON. */
+ int short_compare = 0;
+
+ /* Nonzero if this is a right-shift operation, which can be computed on the
+ original short and then promoted if the operand is a promoted short. */
+ int short_shift = 0;
+
+ /* Nonzero means set RESULT_TYPE to the common type of the args. */
+ int common = 0;
+
+ if (convert_p)
+ {
+ op0 = default_conversion (orig_op0);
+ op1 = default_conversion (orig_op1);
+ }
+ else
+ {
+ op0 = orig_op0;
+ op1 = orig_op1;
+ }
+
+ type0 = TREE_TYPE (op0);
+ type1 = TREE_TYPE (op1);
+
+ /* The expression codes of the data types of the arguments tell us
+ whether the arguments are integers, floating, pointers, etc. */
+ code0 = TREE_CODE (type0);
+ code1 = TREE_CODE (type1);
+
+ /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
+ if (TREE_CODE (op0) == NON_LVALUE_EXPR)
+ op0 = TREE_OPERAND (op0, 0);
+ if (TREE_CODE (op1) == NON_LVALUE_EXPR)
+ op1 = TREE_OPERAND (op1, 0);
+
+ /* If an error was already reported for one of the arguments,
+ avoid reporting another error. */
+
+ if (code0 == ERROR_MARK || code1 == ERROR_MARK)
+ return error_mark_node;
+
+ switch (code)
+ {
+ case PLUS_EXPR:
+ /* Handle the pointer + int case. */
+ if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
+ return pointer_int_sum (PLUS_EXPR, op0, op1);
+ else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
+ return pointer_int_sum (PLUS_EXPR, op1, op0);
+ else
+ common = 1;
+ break;
+
+ case MINUS_EXPR:
+ /* Subtraction of two similar pointers.
+ We must subtract them as integers, then divide by object size. */
+ if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
+ && comp_target_types (type0, type1))
+ return pointer_diff (op0, op1);
+ /* Handle pointer minus int. Just like pointer plus int. */
+ else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
+ return pointer_int_sum (MINUS_EXPR, op0, op1);
+ else
+ common = 1;
+ break;
+
+ case MULT_EXPR:
+ common = 1;
+ break;
+
+ case TRUNC_DIV_EXPR:
+ case CEIL_DIV_EXPR:
+ case FLOOR_DIV_EXPR:
+ case ROUND_DIV_EXPR:
+ case EXACT_DIV_EXPR:
+ if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
+ && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
+ {
+ if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
+ resultcode = RDIV_EXPR;
+ else
+ shorten = 1;
+ common = 1;
+ }
+ break;
+
+ case BIT_AND_EXPR:
+ case BIT_ANDTC_EXPR:
+ case BIT_IOR_EXPR:
+ case BIT_XOR_EXPR:
+ if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
+ shorten = -1;
+ /* If one operand is a constant, and the other is a short type
+ that has been converted to an int,
+ really do the work in the short type and then convert the
+ result to int. If we are lucky, the constant will be 0 or 1
+ in the short type, making the entire operation go away. */
+ if (TREE_CODE (op0) == INTEGER_CST
+ && TREE_CODE (op1) == NOP_EXPR
+ && TYPE_PRECISION (type1) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))
+ && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0))))
+ {
+ final_type = result_type;
+ op1 = TREE_OPERAND (op1, 0);
+ result_type = TREE_TYPE (op1);
+ }
+ if (TREE_CODE (op1) == INTEGER_CST
+ && TREE_CODE (op0) == NOP_EXPR
+ && TYPE_PRECISION (type0) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))
+ && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
+ {
+ final_type = result_type;
+ op0 = TREE_OPERAND (op0, 0);
+ result_type = TREE_TYPE (op0);
+ }
+ break;
+
+ case TRUNC_MOD_EXPR:
+ 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;
+ }
+}
+\f
+/* 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;
+}
+\f
+/* 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");
+}
+\f
+/* 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);
+ }
+}
+\f
+/* 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;
+ }
+}
+\f
+/* 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));
+}
+\f
+/* 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;
+}
+\f
+/* 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);
+}
+\f
+/* 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);
+}
+\f
+/* 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;
+}
+\f
+/* 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;
+}
+\f
+/* 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);
+}
+\f
+/* 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;
+}
+\f
+/* 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;
+}
+\f
+/* 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 ();
+}
+\f
+/* 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;
+ }
+}
+\f
+/* 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;
+}
projects / gcc.git / commitdiff