aq banking wizard segfault

[Archimedes Submerged]

I have debugged a segfault arising when using  --enable-hbci --enable-ofx
--with-ofx-prefix=/opt/gnucash/libofx
--with-aqbanking-dir=/opt/gnucash/aqbanking, using gwenhywfar-2.3.0
 compiled from source, libxml++-1.0.5 compiled from source, libofx-CVS
compiled from source (apparently the only way to get a revision more recent
than libofx-0.8.0), aqbanking-2.1.0 with one patch to fix a different
segfault (reported to aqbanking-devel).

The segfault happens only if you enter the hbci setup druid from the second
page, after some existing hbci accounts are listed.  The problem is in
druid-hbci-utils.c, where hbci account pointers are kept in a hash table.
If AB_Banking_Fini is called, those pointers become stale.  But when the
setup druid button is pressed, AB_Banking_Fini is called.

Workaround:  enter the hbci setup druid from the first page and do not use
the setup button on the account list page.

I'm not sure how this ought to be fixed.  Apparently all the hash table is
used for is to allow values from the AB banking account fields to be looked
up when the "apply" button is pressed.  Maybe the best fix would be just
like the workaround:  remove the button from the account list page.  And if
you go back to the first page, the hash table has to be deleted.  (Maybe it
is already, didn't look).