--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -33,7 +33,6 @@ SET(ZLOG_SO_VERSION ${CPACK_PACKAGE_VERS
 message(STATUS "platform : ${CMAKE_SYSTEM}")
 
 add_definitions("-g -Wall -Wstrict-prototypes")
-set(CMAKE_C_FLAGS "-std=c99 -pedantic -D_DEFAULT_SOURCE")
 set(CMAKE_C_FLAGS_DEBUG "-ggdb3 -DDEBUG")
 set(CMAKE_C_FLAGS_RELEASE "-O2")
 
