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diff --git a/gcc/c-convert.c b/gcc/c-convert.c
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+/* Language-level data type conversion for GNU C.
+   Copyright (C) 1987, 1988, 1991, 1998 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, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+
+/* This file contains the functions for converting C expressions
+   to different data types.  The only entry point is `convert'.
+   Every language front end must have a `convert' function
+   but what kind of conversions it does will depend on the language.  */
+
+#include "config.h"
+#include "tree.h"
+#include "flags.h"
+#include "convert.h"
+#include "toplev.h"
+
+/* Change of width--truncation and extension of integers or reals--
+   is represented with NOP_EXPR.  Proper functioning of many things
+   assumes that no other conversions can be NOP_EXPRs.
+
+   Conversion between integer and pointer is represented with CONVERT_EXPR.
+   Converting integer to real uses FLOAT_EXPR
+   and real to integer uses FIX_TRUNC_EXPR.
+
+   Here is a list of all the functions that assume that widening and
+   narrowing is always done with a NOP_EXPR:
+     In convert.c, convert_to_integer.
+     In c-typeck.c, build_binary_op (boolean ops), and truthvalue_conversion.
+     In expr.c: expand_expr, for operands of a MULT_EXPR.
+     In fold-const.c: fold.
+     In tree.c: get_narrower and get_unwidened.  */
+
+/* Subroutines of `convert'.  */
+
+
+
+/* Create an expression whose value is that of EXPR,
+   converted to type TYPE.  The TREE_TYPE of the value
+   is always TYPE.  This function implements all reasonable
+   conversions; callers should filter out those that are
+   not permitted by the language being compiled.  */
+
+tree
+convert (type, expr)
+     tree type, expr;
+{
+  register tree e = expr;
+  register enum tree_code code = TREE_CODE (type);
+
+  if (type == TREE_TYPE (expr)
+      || TREE_CODE (expr) == ERROR_MARK)
+    return expr;
+  if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (TREE_TYPE (expr)))
+    return fold (build1 (NOP_EXPR, type, expr));
+  if (TREE_CODE (TREE_TYPE (expr)) == ERROR_MARK)
+    return error_mark_node;
+  if (TREE_CODE (TREE_TYPE (expr)) == VOID_TYPE)
+    {
+      error ("void value not ignored as it ought to be");
+      return error_mark_node;
+    }
+  if (code == VOID_TYPE)
+    return build1 (CONVERT_EXPR, type, e);
+#if 0
+  /* This is incorrect.  A truncation can't be stripped this way.
+     Extensions will be stripped by the use of get_unwidened.  */
+  if (TREE_CODE (expr) == NOP_EXPR)
+    return convert (type, TREE_OPERAND (expr, 0));
+#endif
+  if (code == INTEGER_TYPE || code == ENUMERAL_TYPE)
+    return fold (convert_to_integer (type, e));
+  if (code == POINTER_TYPE)
+    return fold (convert_to_pointer (type, e));
+  if (code == REAL_TYPE)
+    return fold (convert_to_real (type, e));
+  if (code == COMPLEX_TYPE)
+    return fold (convert_to_complex (type, e));
+
+  error ("conversion to non-scalar type requested");
+  return error_mark_node;
+}