SEGFAULT on SELECT * FROM view

Hi all,

When SELECTing from one particular view, I get reproducible SEGFAULTs in
my pg 9.1.2 production database. To test for hardware errors, I ran
memtest, which succeeded. I then asked for help in #postgres and got
advice to create stacktraces, but I couldn't find the problem yet.

Scenario: VIEW 'vwa' on TABLE 'tba' and some subselects and aggregates.
I've no idea what's wrong with this view, but a
  SELECT * FROM vwa WHERE myid = 1000010 LIMIT 100 OFFSET 0;

and even EXPLAINing this statement SEGFAULTs the server.

gdb trace: http://pgsql.privatepaste.com/eacd1b6c5d
gdb "ec" output: http://pgsql.privatepaste.com/a61db5b564
smaps: http://pgsql.privatepaste.com/3c4f494015

Then I used the definition of vwa, and created vwb, and the very same
SELECT (just with vwb) works perfectly fine. I've a pastebin link
comparing the two view definitions, which I'm willing to share privately
if that helps. The views actually differ, although the look identical
with \d+ in the psql console, in that the newer view names more columns
that were added to the referenced tables lately.

So, you tell me, what's wrong with the old view?

Thanks a lot,
Chris