Andres Freund <andres@2ndquadrant.com> writes:
> On 2013-01-11 15:52:19 -0500, Tom Lane wrote:
>> I agree the scenario doesn't seem all that probable, but what scares me
>> here is that if we use "__builtin_constant_p(elevel) && (elevel) >= ERROR"
>> in some builds, and just "(elevel) >= ERROR" in others, then if there is
>> any code with a multiple-evaluation hazard, it is only buggy in the
>> latter builds. That's sufficiently nasty that I'm willing to give up
>> an optimization that we never had before 9.3 anyway.
> Well, why use it at all then and not just rely on
> __builtin_unreachable() in any recent gcc (and llvm fwiw) and abort()
> otherwise? Then the code is small for anything recent (gcc 4.4 afair)
> and always consistently buggy.
Uh ... because it's *not* unreachable if elevel < ERROR. Otherwise we'd
just mark errfinish as __attribute((noreturn)) and be done. Of course,
that's a gcc-ism too.
regards, tom lane