diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6d6a2b9e4213b3a87917115c6a346b34e528c765..eeb924a1bcafd589ac5e598c0cff7986cae3c0aa 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -147,11 +147,9 @@ endfunction()
 if (CMAKE_COMPILER_IS_GNUCXX)
   get_compiler_version(_GCC_VERSION)
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall")
-  #if (_GCC_VERSION MATCHES "42")
-  #  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall")
-  #else()
-  #  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -fvisibility=hidden")  
-  #endif()
+  if (APPLE AND NOT GCC_VERSION MATCHES "42")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fvisibility=hidden")
+  endif()
 endif()
 
 set(CMAKE_LIBRARY_OUTPUT_DIRECTORY)