1) vte_terminal_set_emulation calls vte_terminal_set_termcap(terminal, NULL, FALSE);
2) vte_terminal_set_termcap gets passed NULL as path and hence it tries to first
open:
        wpath = g_strdup_printf(DATADIR "/" PACKAGE "/termcap/%s",
                                terminal->pvt->emulation ?
                                terminal->pvt->emulation :
                                vte_terminal_get_default_emulation(terminal));
        if (stat(wpath, &st) != 0) {
                g_free(wpath);
                wpath = g_strdup("/etc/termcap");
        }

   If we don't find both files (DATADIR "/" PACKAGE "/termcap/%s" _and_
/etc/termcap)
3) _vte_termcap_new(NULL) gets called and from there on the _vte_termcap termcap
variable is
   NULL all the time and we trigger a whole bunch of "_vte_termcap_find:
assertion `termcap != NULL' failed" warnings.
   We also end up in a segfault as soon as we _vte_termcap_destroy gets called
by the g_cache cleanup handlers
   since we have:

   for (entry = termcap->entries; entry != NULL; entry = nextentry) {

   at the beginning of that function.

I'll attach a patch that fixes the destroy handler to not crash. We could also
simply refuse to start if no termcap
file.