On Tue, Dec 8, 2015 at 12:36 PM John Wiegley <jwiegley@gmail.com> wrote:

Nice backtrace, thank you. I wonder what object XCAR is being applied to, that
it would segfault like this.

Seems garbagy; see my earlier response to Eli.

Does this happen consistently, even if you don't know exactly what caused it?

Nope, it seems quite random. I've probably seen it a total of 3 or 4 times.