diff --git a/extras/Catch.cmake b/extras/Catch.cmake
index b3f90a79..a3885162 100644
--- a/extras/Catch.cmake
+++ b/extras/Catch.cmake
@@ -202,4 +202,5 @@ endfunction()
 
 set(_CATCH_DISCOVER_TESTS_SCRIPT
   ${CMAKE_CURRENT_LIST_DIR}/CatchAddTests.cmake
+  CACHE INTERNAL "Catch2 full path to CatchAddTests.cmake helper file"
 )