diff --git a/gas/ChangeLog b/gas/ChangeLog
index 5d5ece9a46..77f16283c2 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,8 @@
+2002-01-07  Nick Clifton  <nickc@cambridge.redhat.com>
+
+	* read.c (emit_expr): Do not allow 'size' or 'nbytes' to go
+	negative.
+
 2002-01-06  Alan Modra  <amodra@bigpond.net.au>
 
 	* config/tc-m68k.h (md_prepare_relax_scan): Rewrite.
diff --git a/gas/read.c b/gas/read.c
index 5fc9511314..b0446c8d13 100644
--- a/gas/read.c
+++ b/gas/read.c
@@ -3683,7 +3683,7 @@ emit_expr (exp, nbytes)
 	    }
 
 	  nums = generic_bignum + size / CHARS_PER_LITTLENUM;
-	  while (size > 0)
+	  while (size >= CHARS_PER_LITTLENUM)
 	    {
 	      --nums;
 	      md_number_to_chars (p, (valueT) *nums, CHARS_PER_LITTLENUM);
@@ -3694,7 +3694,7 @@ emit_expr (exp, nbytes)
       else
 	{
 	  nums = generic_bignum;
-	  while (size > 0)
+	  while (size >= CHARS_PER_LITTLENUM)
 	    {
 	      md_number_to_chars (p, (valueT) *nums, CHARS_PER_LITTLENUM);
 	      ++nums;
@@ -3703,7 +3703,7 @@ emit_expr (exp, nbytes)
 	      nbytes -= CHARS_PER_LITTLENUM;
 	    }
 
-	  while (nbytes > 0)
+	  while (nbytes >= CHARS_PER_LITTLENUM)
 	    {
 	      md_number_to_chars (p, extra_digit, CHARS_PER_LITTLENUM);
 	      nbytes -= CHARS_PER_LITTLENUM;