bug#20209: GUILE 2.0.11: crash in set_port_filename_x for bytevector ports

[Mark H Weaver]

David Kastrup <address@hidden> writes:

> It's also a rather inscrutable error symptom.  Any chance wrong-type-arg
> can guard against uninitialized/invalid types specifically?

In this case the "bad type tag" was a valid tag, but not the one
intended for ports.  The tags of the returned port indicated that it was
a pair those car contained a non-immediate object located at an unmapped
address, which caused a segfault while trying to print it.

     Mark