diff --git a/cmake/Key4hepConfig.cmake b/cmake/Key4hepConfig.cmake
index 1309ed9f..6dd524ab 100644
--- a/cmake/Key4hepConfig.cmake
+++ b/cmake/Key4hepConfig.cmake
@@ -1,7 +1,8 @@
+# Do not edit this file, it will be overwritten!
+# The template file can be found in
+# https://github.com/key4hep/key4hep-dev-utils/blob/main/defaults/cmake/Key4hepConfig.cmake
+
 macro(key4hep_set_compiler_flags)
-  if (DEFINED KEY4HEP_SET_COMPILER_FLAGS AND NOT KEY4HEP_SET_COMPILER_FLAGS)
-    return()
-  endif()
 
   set(COMPILER_FLAGS "-fPIC -Wall -Wextra -Wpedantic -Wshadow -Wdeprecated")
 
@@ -11,7 +12,10 @@ macro(key4hep_set_compiler_flags)
     set(COMPILER_FLAGS "${COMPILER_FLAGS} -fdiagnostics-color=always")
   endif()
 
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${COMPILER_FLAGS}")
+  if (DEFINED KEY4HEP_SET_COMPILER_FLAGS AND NOT KEY4HEP_SET_COMPILER_FLAGS)
+  else()
+    set(CMAKE_CXX_FLAGS "${COMPILER_FLAGS} ${CMAKE_CXX_FLAGS}")
+  endif()
 
 endmacro()