diff --git a/libc/include/sched.h b/libc/include/sched.h
index 930dd7c85..d08b3baed 100644
--- a/libc/include/sched.h
+++ b/libc/include/sched.h
@@ -50,6 +50,10 @@ extern int sched_setparam(pid_t, const struct sched_param*);
 extern int sched_getparam(pid_t, struct sched_param*);
 extern int sched_rr_get_interval(pid_t, struct timespec*);
 
+#if defined(__CRYSTAX__)
+#define __USE_GNU 1
+#endif
+
 #if defined(__USE_GNU)
 
 extern int clone(int (*)(void*), void*, int, void*, ...);