Re: vectorized CRC on ARM64

On Sat, Apr 4, 2026 at 8:52 PM John Naylor <johncnaylorls(at)gmail(dot)com> wrote:
> Let's see what the buildfarm thinks.

hoatzin is failing with:

[1481/2135] "link" @src/backend/postgres.exe.rsp
FAILED: src/backend/postgres.exe src/backend/postgres.pdb
"link" @src/backend/postgres.exe.rsp
Creating library src\\backend\\postgres.lib
utils_hash_pg_crc.c.obj : error LNK2001: unresolved external symbol
__builtin_constant_p

That should have been pg_integer_constant_p to work on MSVC since
length in bytes is an integer. That symbol is new in the PG19 cycle
and I didn't know about it until now. I've pushed a fix using that,
and appropriate guards. The earlier use of __builtin_constant_p in the
x86 case didn't happen to cause any failures on MSVC for some reason.
That path needs a guard as well, but since that's backpatchable I
handle it later. It's unlikely anyone passing special CFLAGS is using
a non-mainstream compiler, but that's still a potential trap waiting
for someone.

--
John Naylor
Amazon Web Services