fn mainIdle(k: *Kqueue, message: *const SwitchMessage) callconv(.withStackAlign(.c, @max(@alignOf(Thread), @alignOf(Io.fiber.Context)))) noreturn
fn mainIdle(k: *Kqueue, message: *const SwitchMessage) callconv(.withStackAlign(.c, @max(@alignOf(Thread), @alignOf(Io.fiber.Context)))) noreturn { message.handle(k); k.idle(&k.threads.allocated[0]); k.yield(@ptrCast(&k.main_fiber_buffer), .nothing); unreachable; // switched to dead fiber }