--- gforth/engine/dblsub.c	2003/03/09 15:17:02	1.3
+++ gforth/engine/dblsub.c	2006/10/22 20:45:34	1.6
@@ -1,7 +1,7 @@
 /* some routines for double-cell arithmetic
    only used if BUGGY_LONG_LONG
 
-   Copyright (C) 1996,2000 Free Software Foundation, Inc.
+   Copyright (C) 1996,2000,2003 Free Software Foundation, Inc.
  * Copyright (C) 1995  Dirk Uwe Zoller
  *
  * This library is free software; you can redistribute it and/or
@@ -81,6 +81,10 @@ UDCell umdiv (UDCell u, UCell v)
   UCell q = 0, h = u.hi, l = u.lo;
   UDCell res;
 
+  if (v==0)
+    throw(BALL_DIVZERO);
+  if (h>=v)
+    throw(BALL_RESULTRANGE);
   for (;;)
     {
       if (c || h >= v)
@@ -112,8 +116,14 @@ DCell smdiv (DCell num, Cell denom)	/* s
   if (denomsign < 0)
     denom = -denom;
   res = UD2D(umdiv (D2UD(num), denom));
-  if ((numsign^denomsign)<0)
+  if (res.lo > (UCell)CELL_MIN)
+    throw(BALL_RESULTRANGE);
+  if ((numsign^denomsign)<0) {
     res.lo = -res.lo;
+  } else {
+    if (res.lo == CELL_MIN)
+      throw(BALL_RESULTRANGE);
+  }
   if (numsign<0)
     res.hi = -res.hi;
   return res;
@@ -124,14 +134,23 @@ DCell fmdiv (DCell num, Cell denom)	/* f
   /* I have this technique from Andrew Haley */
   DCell res;
   Cell denomsign=denom;
+  Cell numsign;
 
   if (denom < 0) {
     denom = -denom;
     num = dnegate(num);
   }
-  if (num.hi < 0)
+  numsign = num.hi;
+  if (numsign < 0)
     num.hi += denom;
   res = UD2D(umdiv(D2UD(num),denom));
+  if (numsign < 0) {
+    if (res.lo < (UCell)CELL_MIN)
+      throw(BALL_RESULTRANGE);
+  } else {
+    if (res.lo >= (UCell)CELL_MIN)
+      throw(BALL_RESULTRANGE);
+  }
   if (denomsign<0)
     res.hi = -res.hi;
   return res;