diff --git a/libc/arch-x86_64/syscalls/adjtimex.S b/libc/arch-x86_64/syscalls/adjtimex.S
new file mode 100644
index 0000000..292b9f3
--- /dev/null
+++ b/libc/arch-x86_64/syscalls/adjtimex.S
@@ -0,0 +1,15 @@
+/* Generated by gensyscalls.py. Do not edit. */
+
+#include <private/bionic_asm.h>
+
+ENTRY(adjtimex)
+    movl    $__NR_adjtimex, %eax
+    syscall
+    cmpq    $-MAX_ERRNO, %rax
+    jb      1f
+    negl    %eax
+    movl    %eax, %edi
+    call    __set_errno_internal
+1:
+    ret
+END(adjtimex)