Following part is not confirmed other than NetBSD :-)
---------
$NetBSD: TODO,v 1.1 2014/12/12 00:15:43 makoto Exp $

(At least NetBSD/amd64 7.99.1 has following problem)
slirp/compat.cc:141:40: error: 'WIFEXITED' was not declared in this scope
slirp/compat.cc:144:35: error: 'WEXITSTATUS' was not declared in this scope

--- iodev/network/slirp/compat.cc~	2014-04-19 02:14:32.000000000 +0900
+++ iodev/network/slirp/compat.cc	2014-12-12 01:01:35.000000000 +0900
@@ -27,6 +27,10 @@
 
 #include "slirp.h"
 
+#ifdef __NetBSD__
+# include "sys/wait.h"
+#endif
+
