diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6c42da14c375b30c2d46764114c58e8ddd6c6c37..0488b61a3a8f2da61704564213f31328667de145 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,10 +2,16 @@ cmake_minimum_required(VERSION 2.8.7)
 project(macaon2)
 
 
-# for gcc < 5.3
-#add_definitions("-Wall -std=gnu11" )
 add_definitions("-Wall" )
 
+# for gcc < 5.3
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=gnu11")
+
+# better, but needs CMake >= 3.0
+#set_property(GLOBAL PROPERTY CXX_STANDARD 11)
+#set_property(GLOBAL PROPERTY C_STANDARD 11)
+
+
 # activate with cmake -DMACA_EXPORT=TRUE 
 # to use macaon in python/java (with swig)
 if(MACA_EXPORT)