diff --git a/src/Mayaqua/Encrypt.c b/src/Mayaqua/Encrypt.c
index e9b8b745..c52ed16a 100644
--- a/src/Mayaqua/Encrypt.c
+++ b/src/Mayaqua/Encrypt.c
@@ -4761,7 +4761,7 @@ static void MY_SHA0_Transform(MY_SHA0_CTX* ctx) {
 	UCHAR* p = ctx->buf;
 	int t;
 	for(t = 0; t < 16; ++t) {
-		UINT tmp =  *p++ << 24;
+		UINT tmp =  (UINT)*p++ << 24;
 		tmp |= *p++ << 16;
 		tmp |= *p++ << 8;
 		tmp |= *p++;