diff --git a/inc/lektor/internal/os.h b/inc/lektor/internal/os.h
index d71239a3797f168b6e4e374d88b2d3e925104deb..301fdd86517e540a92dac6f4fc05bb7e28e95c3c 100644
--- a/inc/lektor/internal/os.h
+++ b/inc/lektor/internal/os.h
@@ -221,7 +221,7 @@ is_error_broken_pipe(int error)
 
 #if defined(LKT_OS_WIN) && (LKT_OS_WIN == 1)
 PRIVATE_FUNCTION int
-poll(struct pollfd fds[], nfds_t nfds, int timeout)
+poll(fd_set *fds, nfds_t nfds, int timeout)
 {
     return WSAPoll(fds, nfds, timeout);
 }