diff --git a/Tests/RunCMake/CompileFeatures/NonValidTarget2.cmake b/Tests/RunCMake/CompileFeatures/NonValidTarget2.cmake
index eb84692cb..c41bf57cc 100644
--- a/Tests/RunCMake/CompileFeatures/NonValidTarget2.cmake
+++ b/Tests/RunCMake/CompileFeatures/NonValidTarget2.cmake
@@ -4,5 +4,7 @@ set(genexvar $<COMPILE_FEATURES:cxx_final>)
 add_custom_target(copy_target
   COMMAND "${CMAKE_COMMAND}" -E copy "${CMAKE_CURRENT_SOURCE_DIR}/empty.cpp" "${CMAKE_CURRENT_BINARY_DIR}/copied_file${genexvar}.txt"
 )
+set_property(SOURCE "${CMAKE_CURRENT_BINARY_DIR}/copied_file0.cpp" PROPERTY GENERATED 1)
+set_property(SOURCE "${CMAKE_CURRENT_BINARY_DIR}/copied_file1.cpp" PROPERTY GENERATED 1)
 
 add_library(empty "${CMAKE_CURRENT_BINARY_DIR}/copied_file${genexvar}.cpp")