Re: Add last commit LSN to pg_last_committed_xact()

On Fri, Jan 28, 2022 at 7:47 PM Andres Freund <andres(at)anarazel(dot)de> wrote:
>
> On 2022-01-28 16:36:32 -0800, Andres Freund wrote:
> > On 2022-01-28 18:43:57 -0500, James Coleman wrote:
> > > Alternatively I see pg_attribute_aligned, but that's not defined
> > > (AFAICT) on clang, for example, so I'm not sure that'd be acceptable?
> >
> > clang should have it (it defines __GNUC__). The problem would be msvc, I
> > think. Not sure if there's a way to get to a common way of defining it between
> > gcc-like compilers and msvc (the rest is niche enough that we don't need to
> > care about the efficiency I think).
>
> Seems like it's doable:
>
> https://godbolt.org/z/3c5573bTW

Oh, thanks. I'd seen some discussion previously on the list about
clang not supporting it, but that seems to have been incorrect. Also I
didn't know about that compiler site -- that's really neat.

Here's an updated patch series using that approach; the first patch
can (and probably should be) committed separately/regardless to update
the pg_attribute_aligned to be used in MSVC.

Thanks,
James Coleman