Index: parse.c
===================================================================
RCS file: /usr/cvs/cm3/m3-sys/m3cc/gcc/gcc/m3cg/parse.c,v
retrieving revision 1.168
diff -u -w -r1.168 parse.c
--- parse.c	1 Jun 2010 03:51:04 -0000	1.168
+++ parse.c	1 Jun 2010 12:06:55 -0000
@@ -4402,11 +4402,16 @@
   INTEGER (n);
 
   gcc_assert (INTEGRAL_TYPE_P (t));
-  gcc_assert (n > 0);
+  gcc_assert (n >= 0);
 
+  if (n == 0)
+    EXPR_REF (-2) = m3_cast(t, v_zero);
+  else
+  {
   t = sign_extend ? m3_signed_type (t) : m3_unsigned_type (t);
   EXPR_REF (-2) = m3_do_extract (EXPR_REF (-2), EXPR_REF (-1),
                                  build_int_cst (t_int, n), t);
+  }
   EXPR_POP ();
 }
 
@@ -4418,6 +4423,9 @@
   int b = TYPE_PRECISION (t) - n - m;
   tree c, d, e;
 
+  gcc_assert (m >= 0);
+  gcc_assert (n > 0);
+
   if ((a < 0) || (a >= TYPE_PRECISION (t)) ||
       (b < 0) || (b >= TYPE_PRECISION (t)))
     {
@@ -4444,11 +4452,16 @@
 
   gcc_assert (INTEGRAL_TYPE_P (t));
   gcc_assert (m >= 0);
-  gcc_assert (n > 0);
+  gcc_assert (n >= 0);
 
+  if (n == 0)
+    EXPR_REF (-1) = m3_cast(t, v_zero);
+  else
+  {
   t = sign_extend ? m3_signed_type (t) : m3_unsigned_type (t);
   EXPR_REF (-1) = m3_do_fixed_extract (EXPR_REF (-1), m, n, t);
 }
+}
 
 static void
 m3cg_insert (void)