Hello Jeff,
>> I suspect the easiest thing to narrow it down would be to bisect the
>> problem in gcc :(
>
> Their commit r265241 is what broke the PostgreSQL build. It also broke the
> compiler itself--at that commit it was no longer possible to build itself.
> I had to --disable-bootstrap in order to get a r265241 compiler to test
> PostgreSQL on.
It seems they have done a API change around some kind of "range" analysis,
which must have been incomplete.
> Their commit r265375 fixed the ability to compile itself, but built
> PostgreSQL binaries remain broken there and thereafter.
>
> |...]
Thanks a lot for this investigation! I can fill in a gcc bug report. There
would be a enormous work to narrow it down to a small test case, it is
unclear how they can act about it, but at least they would know.
--
Fabien.