Horton

Re: Detection of hadware feature => please do not use signal

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Thomas Munro <thomas.munro@gmail.com>
Cc: Heikki Linnakangas <hlinnaka@iki.fi>, Bastien Roucariès <rouca@debian.org>, pgsql-bugs@lists.postgresql.org
Date: 2024-11-25T00:40:29Z
Lists: pgsql-bugs 
I wrote:
> It's very confusing, especially given this:

> $ gcc -march=armv8-a+crc+fp testarm32.c
> gcc: error: 'armv8-a' does not support feature 'fp'
> gcc: note: valid feature names are: crc simd crypto nocrypto nofp sb predres; did you mean 'nofp'?

> If they think that base armv8-a doesn't include FP, why is there a
> +nofp option?

Bug filed at

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117766

We'll see what they say, but it seems like we need a workaround
in any case.

			regards, tom lane

Commits

  1. Update configure probes for CFLAGS needed for ARM CRC instructions.

  2. Support runtime CRC feature probing on NetBSD/ARM using sysctl().

  3. Use auxv to check for CRC32 instructions on ARM.

  4. Improve our method for probing the availability of ARM CRC instructions.