diff --git a/CMakeLists.txt b/CMakeLists.txt
index f8ef4aa..866b3ab 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,7 +1,13 @@
 cmake_minimum_required(VERSION 2.6)
 
 PROJECT(ubus C)
-ADD_DEFINITIONS(-Os -Wall -Werror --std=gnu99 -g3 -Wmissing-declarations)
+
+ADD_DEFINITIONS(-Wall -Werror)
+IF(CMAKE_C_COMPILER_VERSION VERSION_GREATER 6)
+	ADD_DEFINITIONS(-Wextra -Werror=implicit-function-declaration)
+	ADD_DEFINITIONS(-Wformat -Werror=format-security -Werror=format-nonliteral)
+ENDIF()
+ADD_DEFINITIONS(-Os -std=gnu99 -g3 -Wmissing-declarations -Wno-unused-parameter)
 
 OPTION(BUILD_LUA "build Lua plugin" ON)
 OPTION(BUILD_EXAMPLES "build examples" ON)