https://gitlab.gnome.org/GNOME/vte/-/issues/72
https://bugs.gentoo.org/835489
https://bugs.gentoo/org/554416

From 1c1de9e9119cf1e0ef45a594ca9bbf306d2209cb Mon Sep 17 00:00:00 2001
From:
Date: Fri, 12 Mar 2021 08:41:13 -0600
Subject: [PATCH] Expanded non-standard W_EXITCODE macro for Musl compatibility

--- a/src/widget.cc
+++ b/src/widget.cc
@@ -20,8 +20,6 @@
 
 #include "widget.hh"
 
-#include <sys/wait.h> // for W_EXITCODE
-
 #include <exception>
 #include <new>
 #include <string>
@@ -235,7 +233,7 @@ void
 Widget::dispose() noexcept
 {
         if (m_terminal->terminate_child()) {
-                int status = W_EXITCODE(0, SIGKILL);
+                int status = (0) << 8 | (SIGKILL); // W_EXITCODE(ret, sig)
                 emit_child_exited(status);
         }
 }