diff --git a/CMakeLists.txt b/CMakeLists.txt
index e9cfad7..9ca29d9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -36,7 +36,7 @@
 SET(SECURITY_FLAGS " -fstack-protector-strong -fPIE -fPIC -D_FORTIFY_SOURCE=2 -Wformat -Wformat-security")
 SET(CMAKE_CXX_FLAGS_RELEASE  "${CMAKE_CXX_FLAGS_RELEASE} ${SECURITY_FLAGS}" )
 SET(CMAKE_CXX_FLAGS_RELWITHDEBINFO  "${CMAKE_CXX_FLAGS_RELWITHDEBINFO} ${SECURITY_FLAGS}" )
-SET(CMAKE_C_FLAGS_MINSIZEREL  "${CMAKE_C_FLAGS_MINSIZEREL} ${SECURITY_FLAGS}" )
+SET(CMAKE_CXX_FLAGS_MINSIZEREL  "${CMAKE_C_FLAGS_MINSIZEREL} ${SECURITY_FLAGS}" )
 
 #add_definitions(-DBOOST_ASIO_ENABLE_HANDLER_TRACKING)
 add_definitions(-DBOOST_ERROR_CODE_HEADER_ONLY)