Re: Re: [COMMITTERS] pgsql: Disable -faggressive-loop-optimizations in gcc 4.8+ for pre-9.2

On Tue, Jan 20, 2015 at 10:30 AM, Alvaro Herrera
<alvherre(at)2ndquadrant(dot)com> wrote:
> Tom Lane wrote:
>> Disable -faggressive-loop-optimizations in gcc 4.8+ for pre-9.2 branches.
>> With this optimization flag enabled, recent versions of gcc can generate
>> incorrect code that assumes variable-length arrays (such as oidvector)
>> are actually fixed-length because they're embedded in some larger struct.
>> The known instance of this problem was fixed in 9.2 and up by commit
>> 8137f2c32322c624e0431fac1621e8e9315202f9 and followon work, which hides
>> actually-variable-length catalog fields from the compiler altogether.
>> And we plan to gradually convert variable-length fields to official
>> "flexible array member" notation over time, which should prevent this type
>> of bug from reappearing as gcc gets smarter. We're not going to try to
>> back-port those changes into older branches, though, so apply this
>> band-aid instead.
>
> Would anybody object to me pushing this commit to branches 8.2 and 8.3?

Since those branches are out of support, I am not sure what the point
is. If we want people to be able to use those branches reasonably we
need to back-port fixes for critical security and stability issues,
not just this one thing.

But maybe I am missing something.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company