diff --git a/cpp/build.sh b/cpp/build.sh
index 984ae9d365..1279725162 100755
--- a/cpp/build.sh
+++ b/cpp/build.sh
@@ -18,6 +18,7 @@ do
         case $arg in
              t)
                 BUILD_TYPE=$OPTARG # BUILD_TYPE
+                KNOWHERE_OPTS="${KNOWHERE_OPTS} -t $OPTARG"
                 ;;
              u)
                 echo "Build and run unittest cases" ;