convert_to_pointer vs partial_int modes

[DJ Delorie]

One last invalid assumption tonight.  When pointers happen to be
partial_ints, sometimes the lang_hook chooses to do nothing to convert
it.  In that case, this patch avoids infinite recursion.

	* convert.c (convert_to_pointer): Avoid recursion if no
	conversion is needed.

Index: convert.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/convert.c,v
retrieving revision 1.63
diff -p -U3 -r1.63 convert.c
--- convert.c	26 May 2005 04:38:51 -0000	1.63
+++ convert.c	28 May 2005 03:05:51 -0000
@@ -41,6 +41,8 @@ Software Foundation, 59 Temple Place - S
 tree
 convert_to_pointer (tree type, tree expr)
 {
+  tree newexpr;
+
   if (integer_zerop (expr))
     {
       expr = build_int_cst (type, 0);
@@ -60,10 +62,11 @@ convert_to_pointer (tree type, tree expr
       if (TYPE_PRECISION (TREE_TYPE (expr)) == POINTER_SIZE)
 	return build1 (CONVERT_EXPR, type, expr);
 
-      return
-	convert_to_pointer (type,
-			    convert (lang_hooks.types.type_for_size
-				     (POINTER_SIZE, 0), expr));
+      newexpr = convert (lang_hooks.types.type_for_size
+			 (POINTER_SIZE, 0), expr);
+      if (newexpr == expr)
+	return expr;
+      return convert_to_pointer (type, newexpr);
 
     default:
       error ("cannot convert to a pointer type");