diff --git a/.ci/windows/build.sh b/.ci/windows/build.sh
index 82d62428a8..3b413b6de1 100644
--- a/.ci/windows/build.sh
+++ b/.ci/windows/build.sh
@@ -17,7 +17,7 @@ fi
 
 [ -z "$WINDEPLOYQT" ] && { echo "WINDEPLOYQT environment variable required."; exit 1; }
 
-export EXTRA_CMAKE_FLAGS=("${EXTRA_CMAKE_FLAGS[@]}" $@)
+EXTRA_CMAKE_FLAGS=("${EXTRA_CMAKE_FLAGS[@]}" $@)
 
 echo "${EXTRA_CMAKE_FLAGS[@]}"