1 files changed, 1 insertions, 0 deletions
diff --git a/bignum.c b/bignum.c
index 77dec0f6cf..7b6e257e62 100644
--- a/bignum.c
+++ b/bignum.c
@@ -2125,6 +2125,7 @@ bigmul1_karatsuba(VALUE x, VALUE y)
     }
     else {
 	t2 = Qundef;
+	t2n = 0;
 
 	/* copy 0 into low bytes of the result (z0) */
 	for (i = 0; i < 2 * n; i++) zds[i] = 0;