* Don't ignore errors from writing to stderr. That way, when

nix-store -r (or some other operation) is started via ssh, it will
  at least have a chance of terminating quickly when the connection is
  killed.  Right now it just runs to completion, because it never
  notices that stderr is no longer connected to anything.  Of course
  it would be better if sshd would just send a SIGHUP, but it doesn't
  (https://bugzilla.mindrot.org/show_bug.cgi?id=396).

src/libutil/util.cc

@@ -469,11 +469,7 @@ void warnOnce(bool & haveWarned, const format & f)
 
 static void defaultWriteToStderr(const unsigned char * buf, size_t count)
 {
-    try {
-        writeFull(STDERR_FILENO, buf, count);
-    } catch (SysError & e) {
-        /* ignore EPIPE etc. */
-    }
+    writeFull(STDERR_FILENO, buf, count);
 }