diff --git a/posix/JackPosixSemaphore.cpp b/posix/JackPosixSemaphore.cpp
index 5103f1cf..49012312 100644
--- a/posix/JackPosixSemaphore.cpp
+++ b/posix/JackPosixSemaphore.cpp
@@ -17,8 +17,6 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
 */
 
-// #define _POSIX_C_SOURCE 200112L
-
 #include "JackPosixSemaphore.h"
 #include "JackTools.h"
 #include "JackConstants.h"