diff --git a/testsuite/memxor-test.c b/testsuite/memxor-test.c
index 3319433..84d0a7d 100644
--- a/testsuite/memxor-test.c
+++ b/testsuite/memxor-test.c
@@ -73,11 +73,15 @@ test_memxor3 (const uint8_t *ain, const uint8_t *bin, const uint8_t *c,
   ASSERT (MEMEQ (size, dst, c));
   ASSERT (dst[-1] == 17);
   ASSERT (dst[size] == 17);
+
 }
 
 void
 test_main(void)
 {
+  uint8_t dst_buf[MAX_SIZE];
+  uint8_t *c_buf;
+  uint8_t *d_buf;
   const uint8_t *a = H("ecc8737f 38f2f9e8 86b9d84c 42a9c7ef"
 		       "27a50860 49c6be97 c5cc6c35 3981b367"
 		       "f8b4397b 951e3b2f 35749fe1 25884fa6"
@@ -144,4 +148,15 @@ test_main(void)
 	  for (align_b = 0; align_b < ALIGN_SIZE; align_b++)
 	    test_memxor3 (a, b, c, size[i], align_dst, align_a, align_b);
 	}
+
+  c_buf = malloc(111);
+  d_buf = malloc(111);
+  memset(c_buf, 1, 111);
+  memset(d_buf, 3, 111);
+
+  memxor3 (dst_buf+13, c_buf+96, d_buf, 15);
+
+  ASSERT(dst_buf[14] == 2);
+  free(c_buf);
+  free(d_buf);
 }