diff --git a/CMakeLists.txt b/CMakeLists.txt
index e8a7d0b..00ade1c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -5,7 +5,7 @@ cmake_minimum_required(VERSION 2.8)
 #find_package(libssh)
 
 # Build the sshping binary
-set(CMAKE_CXX_FLAGS "-I ${CMAKE_CURRENT_SOURCE_DIR}/ext/ -Wall")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -I ${CMAKE_CURRENT_SOURCE_DIR}/ext/")
 add_executable(${PROJECT_NAME} src/sshping.cxx)
 target_link_libraries(${PROJECT_NAME} ssh)
 install(TARGETS ${PROJECT_NAME} DESTINATION bin)