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From: Thomas Munro <thomas.munro@gmail.com>
Date: Fri, 29 Mar 2024 16:14:37 +1300
Message-ID: <CA+hUKG+7_ON7hd_oB6YjD4Tx23wL4E1UBSWg6C+O1brMgDB58A@mail.gmail.com>
Subject: Re: AIX support
To: Noah Misch <noah@leadboat.com>
Cc: Sriram RK <sriram.rk@outlook.com>, Tom Lane <tgl@sss.pgh.pa.us>, 
	Alvaro Herrera <alvherre@alvh.no-ip.org>, 
	"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
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On Fri, Mar 29, 2024 at 4:00=E2=80=AFPM Thomas Munro <thomas.munro@gmail.co=
m> wrote:
> On Fri, Mar 29, 2024 at 3:48=E2=80=AFPM Noah Misch <noah@leadboat.com> wr=
ote:
> > The thread Alvaro and Tom cited contains an analysis.  It's a compiler =
bug.
> > You can get past the compiler bug by upgrading your compiler; both ibm-=
clang
> > 17.1.1.2 and gcc 13.2.0 are free from the bug.
>
> For the specific issue that triggered that, I strongly suspect that it
> would go away if we just used smgrzeroextend() instead of smgrextend()
> using that variable with the alignment requirement, since, as far as I
> can tell from build farm clues, the otherwise similar function-local
> static variable used by the former (ie one that the linker must still
> control the location of AFAIK?) seems to work fine.

Oh, sorry, I had missed the part where newer compilers fix the issue
too.  Old out-of-support versions of AIX running old compilers, what
fun.