diff --git a/libc/include/sys/prctl.h b/libc/include/sys/prctl.h
index f66f6f5..8c61677 100644
--- a/libc/include/sys/prctl.h
+++ b/libc/include/sys/prctl.h
@@ -31,13 +31,6 @@
 #include <linux/prctl.h>
 #include <sys/cdefs.h>
 
-/* These should appear in the uapi headers at some point, but they're not there right now. */
-#if !defined(PR_SET_TIMERSLACK_PID)
-#define PR_SET_TIMERSLACK_PID 41
-#else
-#error PR_SET_TIMERSLACK_PID defined twice
-#endif
-
 __BEGIN_DECLS
 
 /* IMPORTANT NOTE: This function is declared as taking a variable number