1 files changed, 1 insertions, 1 deletions
diff --git a/bignum.c b/bignum.c
index 3ddc50c673..c58de5d5bb 100644
--- a/bignum.c
+++ b/bignum.c
@@ -920,7 +920,7 @@ bigdivrem(x, y, divp, modp)
     if (modp) {			/* just normalize remainder */
 	*modp = rb_big_clone(z);
 	zds = BDIGITS(*modp);
-	while (!zds[ny-1]) ny--;
+	while (ny-- && !zds[ny]); ++ny;
 	if (dd) {
 	    t2 = 0; i = ny;
 	    while(i--) {