diff --git a/libc/arch-aarch64/syscalls/setitimer.S b/libc/arch-aarch64/syscalls/setitimer.S
new file mode 100644
index 0000000..aa0c0c2
--- /dev/null
+++ b/libc/arch-aarch64/syscalls/setitimer.S
@@ -0,0 +1,23 @@
+/* Generated by gensyscalls.py. Do not edit. */
+
+#include <asm/unistd.h>
+#include <linux/err.h>
+#include <machine/asm.h>
+
+ENTRY(setitimer)
+    stp     x29, x30, [sp, #-16]!
+    mov     x29,  sp
+    str     x8,       [sp, #-16]!
+
+    mov     x8, __NR_setitimer
+    svc     #0
+
+    ldr     x8,       [sp], #16
+    ldp     x29, x30, [sp], #16
+
+    cmn     x0, #(MAX_ERRNO + 1)
+    cneg    x0, x0, hi
+    b.hi    __set_errno
+
+    ret
+END(setitimer)