diff --git a/CMakeLists.txt b/CMakeLists.txt
index 48f6421..cf14682 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -18,7 +18,6 @@ set(VERSION_PATCHLEVEL     "12")
 set(VERSION_SO             "1")
 set(PACKAGE_VERSION "${VERSION_MAJOR}.${VERSION_MINOR}.${VERSION_PATCHLEVEL}")
 set(PROJECT_BUGREPORT_PATH "https://github.com/LibVNC/libvncserver/issues")
-set(CMAKE_C_FLAGS "-O2 -W -Wall -g")
 set(LIBVNCSERVER_DIR ${CMAKE_CURRENT_SOURCE_DIR}/libvncserver)
 set(COMMON_DIR ${CMAKE_CURRENT_SOURCE_DIR}/common)
 set(LIBVNCCLIENT_DIR ${CMAKE_CURRENT_SOURCE_DIR}/libvncclient)