diff --git a/libc/include/sched.h b/libc/include/sched.h
index 6600bae..33b9ad6 100644
--- a/libc/include/sched.h
+++ b/libc/include/sched.h
@@ -69,8 +69,9 @@
 #define CLONE_CHILD_SETTID   0x01000000
 #define CLONE_STOPPED        0x02000000
 
-extern int    clone(int (*fn)(void*), void *child_stack, int flags, void *arg);
-extern pid_t  __clone(int, void *);
+#ifdef __GNU_SOURCE
+extern int clone(int (*fn)(void *), void *child_stack, int flags, void*  arg, ...);
+#endif
 
 __END_DECLS
 
diff --git a/libc/include/sys/linux-unistd.h b/libc/include/sys/linux-unistd.h
index 12f7704..9a151d2 100644
--- a/libc/include/sys/linux-unistd.h
+++ b/libc/include/sys/linux-unistd.h
@@ -10,7 +10,7 @@
 pid_t            __fork (void);
 pid_t            _waitpid (pid_t, int*, int, struct rusage*);
 int              waitid (int, pid_t, struct siginfo_t*, int,void*);
-pid_t            __clone (int (*fn)(void*), void *child_stack, int flags, void *arg);
+pid_t            __sys_clone (int, void*, int*, void*, int*);
 int              execve (const char*, char* const*, char* const*);
 int              setuid (uid_t);
 uid_t            getuid (void);