Re: disallow big-endian on aarch64

On 10/2/25 22:16, Nathan Bossart wrote:
> Some recent work involving SIMD instructions on AArch64 made me wonder
> whether we support $SUBJECT. For reference, AArch64 is bi-endian, but
> AFAICT all current AAarch64 buildfarm machines are on macOS, Linux, or
> FreeBSD, which appear to require little-endian [0] [1] [2]. I know there
> are efforts to support Windows on AAarch64, but that requires
> little-endian, too [3]. Given the apparent convergence on little-endian,
> IMHO we should require it for Postgres, too. The attached patch adds some
> configure-time checks for this.
>

I don't follow the reasoning. If there are no aarch64 platforms running
in big-endian mode (at least not supported ones), then how would you
even build Postgres in such environment?

Also, what's the benefit of disabling it? Is it about disabling
something we can't meaningfully test (even though we still support other
big-endian platforms, right?). Or does it affect the SIMD stuff somehow?

regards

--
Tomas Vondra