it hangs when it started.
$ pd pd-hangs-serialize.pd
watchdog: signaling pd...
watchdog: signaling pd...
max size for a Tcl value (2147483647 bytes) exceeded
watchdog: signaling pd...
watchdog: signaling pd...
Aborted (core dumped)
watchdog: signaling pd...
watchdog: signaling pd...
^CPd: signal 2
kim@computer:~/$
this patch only crashed on 0.48.1. It's ok on old version of Pd.