diff --git a/libc/arch-x86/syscalls.mk b/libc/arch-x86/syscalls.mk
index b7d1e08..6d368b3 100644
--- a/libc/arch-x86/syscalls.mk
+++ b/libc/arch-x86/syscalls.mk
@@ -55,6 +55,7 @@
 syscall_src += arch-x86/syscalls/eventfd.S
 syscall_src += arch-x86/syscalls/execve.S
 syscall_src += arch-x86/syscalls/faccessat.S
+syscall_src += arch-x86/syscalls/fallocate64.S
 syscall_src += arch-x86/syscalls/fchdir.S
 syscall_src += arch-x86/syscalls/fchmod.S
 syscall_src += arch-x86/syscalls/fchmodat.S