diff --git a/libc/arch-sh/syscalls.mk b/libc/arch-sh/syscalls.mk
index ac12ae4..c848954 100644
--- a/libc/arch-sh/syscalls.mk
+++ b/libc/arch-sh/syscalls.mk
@@ -41,6 +41,7 @@
 syscall_src += arch-sh/syscalls/prctl.S
 syscall_src += arch-sh/syscalls/capget.S
 syscall_src += arch-sh/syscalls/capset.S
+syscall_src += arch-sh/syscalls/sigaltstack.S
 syscall_src += arch-sh/syscalls/acct.S
 syscall_src += arch-sh/syscalls/read.S
 syscall_src += arch-sh/syscalls/write.S