diff --git a/ksw2_extd2_sse.c b/ksw2_extd2_sse.c
index c638738..3130eec 100644
--- a/ksw2_extd2_sse.c
+++ b/ksw2_extd2_sse.c
@@ -50,7 +50,7 @@ void ksw_extd2_sse(void *km, int qlen, const uint8_t *query, int tlen, const uin
 	__m128i *u, *v, *x, *y, *x2, *y2, *s, *p = 0;
 
 	ksw_reset_extz(ez);
-	if (m <= 1 || qlen <= 0 || tlen <= 0 || w < 0) return;
+	if (m <= 1 || qlen <= 0 || tlen <= 0) return;
 
 	if (q2 + e2 < q + e) t = q, q = q2, q2 = t, t = e, e = e2, e2 = t; // make sure q+e no larger than q2+e2
 
@@ -63,6 +63,7 @@ void ksw_extd2_sse(void *km, int qlen, const uint8_t *query, int tlen, const uin
 	sc_mis_ = _mm_set1_epi8(mat[1]);
 	m1_     = _mm_set1_epi8(m - 1); // wildcard
 
+	if (w < 0) w = tlen > qlen? tlen : qlen;
 	wl = wr = w;
 	tlen_ = (tlen + 15) / 16;
 	n_col_ = ((w + 1 < tlen? (w + 1 < qlen? w + 1 : qlen): tlen) + 15) / 16 + 1;
diff --git a/ksw2_extz2_sse.c b/ksw2_extz2_sse.c
index 16f4fcd..f728619 100644
--- a/ksw2_extz2_sse.c
+++ b/ksw2_extz2_sse.c
@@ -41,7 +41,7 @@ void ksw_extz2_sse(void *km, int qlen, const uint8_t *query, int tlen, const uin
 	__m128i *u, *v, *x, *y, *s, *p = 0;
 
 	ksw_reset_extz(ez);
-	if (m <= 0 || qlen <= 0 || tlen <= 0 || w < 0) return;
+	if (m <= 0 || qlen <= 0 || tlen <= 0) return;
 
 	zero_   = _mm_set1_epi8(0);
 	q_      = _mm_set1_epi8(q);
@@ -55,6 +55,7 @@ void ksw_extz2_sse(void *km, int qlen, const uint8_t *query, int tlen, const uin
 	m1_     = _mm_set1_epi8(m - 1); // wildcard
 	max_sc_ = _mm_set1_epi8(mat[0] + (q + e) * 2);
 
+	if (w < 0) w = tlen > qlen? tlen : qlen;
 	wl = wr = w;
 	tlen_ = (tlen + 15) / 16;
 	n_col_ = ((w + 1 < tlen? (w + 1 < qlen? w + 1 : qlen): tlen) + 15) / 16 + 1;
diff --git a/main.c b/main.c
index c554bd9..16d5d58 100644
--- a/main.c
+++ b/main.c
@@ -10,7 +10,7 @@
 #include "minimap.h"
 #include "mmpriv.h"
 
-#define MM_VERSION "2.0-r188-dirty"
+#define MM_VERSION "2.0-r189-dirty"
 
 void liftrlimit()
 {