MSVC odd TAP test problem

I have been working on enabling the remaining TAP tests on MSVC build in
the buildfarm client, but I have come across an odd problem. The bin
tests all run fine, but the recover tests crash and in such a way as to
crash the buildfarm client itself and require some manual cleanup. This
happens at some stage after the tests have run (the final "ok" is
output) but before the END handler in PostgresNode.pm (I put some traces
in there to see if I could narrow down where there were problems).

The symptom is that this appears at the end of the output when the
client calls "vcregress.pl taptest src/test/recover":

Terminating on signal SIGBREAK(21)
Terminating on signal SIGBREAK(21)
Terminate batch job (Y/N)?

And at that point there is nothing at all apparently running, according
to Sysinternals Process Explorer, including the buildfarm client.

It's 100% repeatable on bowerbird, and I'm a bit puzzled about how to
fix it.

Anyone have any clues?

cheers

andrew

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Andrew Dunstan https://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services