diff --git a/Makefile b/Makefile
index 19f48fc..d324e1f 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 TARGET = ciadpi
 
-CPPFLAGS = -D_XOPEN_SOURCE=600
+CPPFLAGS = -D_DEFAULT_SOURCE
 CFLAGS += -I. -std=c99 -Wall -Wno-unused -O2
 WIN_LDFLAGS = -lws2_32 -lmswsock
 
diff --git a/desync.c b/desync.c
index 7a4be2b..b7c3bd0 100644
--- a/desync.c
+++ b/desync.c
@@ -1,5 +1,3 @@
-#define _DEFAULT_SOURCE
-
 #include "desync.h"
 
 #include <stdio.h>