https://bugs.gentoo.org/944149
https://github.com/racket/racket/issues/5183
https://github.com/racket/racket/commit/72b83f784ad1c6fb6ee3fb7b31df165bebfb21ed

From 72b83f784ad1c6fb6ee3fb7b31df165bebfb21ed Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Sun, 19 Jan 2025 11:03:31 -0700
Subject: [PATCH] rktio: add missing signal-handler argument

Closes #5183
--- a/rktio/rktio_process.c
+++ b/rktio/rktio_process.c
@@ -390,7 +390,7 @@ void centralized_done_with_process_id(int pid, int in_group)
   pthread_mutex_unlock(&child_wait_lock);
 }
 
-static void got_sigchld()
+static void got_sigchld(int ignored)
 { 
   /* handle doesn't need to to anything, since sigwait()
      in a thread does the work. */