diff --git a/lib/std/os/linux.zig b/lib/std/os/linux.zig
index a99cabfeab1cacefd6cc6f74d88b2df84c4a8e2f..74b0dae90e2397d6d1e3cc7cb1c42e60288d7b4c 100644
--- a/lib/std/os/linux.zig
+++ b/lib/std/os/linux.zig
@@ -2221,7 +2221,7 @@ pub fn epoll_pwait(epoll_fd: i32, events: [*]epoll_event, maxevents: u32, timeou
         @as(usize, @intCast(maxevents)),
         @as(usize, @bitCast(@as(isize, timeout))),
         @intFromPtr(sigmask),
-        @sizeOf(sigset_t),
+        NSIG / 8,
     );
 }