pcb crashes when --lib-newlib option argument contains link cycles

On July 11th, 2022 Britton Kerin in the geda-user mailing list:

e.g.:

$ pwd
/tmp/test_dir
$ ls
foo/
$ file foo/foo
foo/foo: symbolic link to ../foo
$ pcb --lib-newlib /tmp/test_dir
Segmentation fault (core dumped)

It crashes on mutual links and probably all kinds of cycles, the core
dump (attached) looks like clear stack overflow.

Britton