diff --git a/crypto/mem_clr.c b/crypto/mem_clr.c
index e4b7f540b0bd12dd03608b52e8214332cb1a8b72..75cbfb374e3bd4e09af7e9dd0999a7e39a8b0c32 100644
--- a/crypto/mem_clr.c
+++ b/crypto/mem_clr.c
@@ -68,7 +68,7 @@ void OPENSSL_cleanse(void *ptr, size_t len)
 	while(loop--)
 		{
 		*(p++) = cleanse_ctr;
-		cleanse_ctr += (17 + (unsigned char)((int)p & 0xF));
+		cleanse_ctr += (17 + (unsigned char)((unsigned long)p & 0xF));
 		}
 	if(memchr(ptr, cleanse_ctr, len))
 		cleanse_ctr += 63;