diff -Nur patch-2.5.9.orig/pch.c patch-2.5.9/pch.c
--- patch-2.5.9.orig/pch.c	2007-08-26 17:56:57.000000000 +1000
+++ patch-2.5.9/pch.c	2007-08-29 07:23:16.000000000 +1000
@@ -617,9 +617,8 @@
 	      }
 
 	    is_empty = i == NONE || st[i].st_size == 0;
-	    if ((! is_empty) < p_says_nonexistent[reverse ^ is_empty])
+	    if (((! is_empty) < p_says_nonexistent[reverse ^ is_empty]) && (i0 != NONE))
 	      {
-		assert (i0 != NONE);
 		reverse ^=
 		  ok_to_reverse
 		    ("The next patch%s would %s the file %s,\nwhich %s!",