diff --git a/lib/std/os/linux.zig b/lib/std/os/linux.zig
index 39d3b6bf7edd640a78ecf8e8dafb9ead67c876ab..60885d1ba5803ac16e53c99516c60f576b5535e5 100644
--- a/lib/std/os/linux.zig
+++ b/lib/std/os/linux.zig
@@ -2242,7 +2242,7 @@ 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,
     );
 }