diff --git a/scripts/ports.cmake b/scripts/ports.cmake
index 026555e41b5a35..0ff66379e16d00 100644
--- a/scripts/ports.cmake
+++ b/scripts/ports.cmake
@@ -124,8 +124,15 @@ file(TO_CMAKE_PATH "${PACKAGES_DIR}" PACKAGES_DIR)
 
 set(CURRENT_INSTALLED_DIR "${_VCPKG_INSTALLED_DIR}/${TARGET_TRIPLET}" CACHE PATH "Location to install final packages")
 
-if(PORT)
+if(DEFINED CURRENT_BUILDTREES_DIR)
+    file(TO_CMAKE_PATH "${CURRENT_BUILDTREES_DIR}" CURRENT_BUILDTREES_DIR)
+elseif(PORT)
     set(CURRENT_BUILDTREES_DIR "${BUILDTREES_DIR}/${PORT}")
+endif()
+
+if(DEFINED CURRENT_PACKAGES_DIR)
+    file(TO_CMAKE_PATH "${CURRENT_PACKAGES_DIR}" CURRENT_PACKAGES_DIR)
+elseif(PORT)
     set(CURRENT_PACKAGES_DIR "${PACKAGES_DIR}/${PORT}_${TARGET_TRIPLET}")
 endif()