diff --git a/src/sync/ntapi_tt_sync_block.c b/src/sync/ntapi_tt_sync_block.c
index bcb9691..b37659a 100644
--- a/src/sync/ntapi_tt_sync_block.c
+++ b/src/sync/ntapi_tt_sync_block.c
@@ -60,7 +60,8 @@ int32_t __stdcall __ntapi_tt_sync_block_lock(
 	if (sync_block->tid == tid) return NT_STATUS_SUCCESS;
 
 	/* yield to server? */
-	if ((sync_block->flags & NT_SYNC_BLOCK_YIELD_TO_SERVER) && (tid != sync_block->srvtid)) {
+	if ((sync_block->flags & NT_SYNC_BLOCK_YIELD_TO_SERVER)
+			&& ((uint32_t)tid != sync_block->srvtid)) {
 		hwait[0] = sync_block->hserver;
 		hwait[1] = sync_block->hsignal;