On 29/05/2025 10:54, Peter Dyballa wrote:

Am 29.05.2025 um 11:06 schrieb Pádraig Brady <p...@draigbrady.com>:

        <stdin>:59:2: error: instruction requires: AVX-512 ISA
                vmovdqa64       lC0(%rip), %zmm0
                ^

The above suggests that `/opt/local/bin/gcc-mp-14 -std=gnu23 ... -mavx512bw 
-mavx512f -mvpclmulqdq ... -arch x86_64`
isn't enough to support building with AVX-512 ISA.

That should be fine though if the same determination is made at configure time,
which would cause USE_AVX512_CRC32 to _not_ be defined.
You should be able to see the configure time checks with:

  grep -A3 'avx512 pclmul intrinsic exists' config.log

Output is:

        configure:94181: checking if avx512 pclmul intrinsic exists
        configure:94209: /opt/local/bin/gcc-mp-14 -std=gnu23 -o conftest  -mavx512bw 
-mavx512f -mvpclmulqdq -pipe -Os -arch x86_64 -I/opt/local/include -L/opt/local/lib 
-Wl,-headerpad_max_install_names -arch x86_64 conftest.c  >&5
        configure:94209: $? = 0
        configure:94225: result: yes

OK that does suggest the configure test isn't sufficient here
(Nor the patch to that I sent previously).

Since this is for an optional performance enhancement,
you should be able to bypass this build issue with:

  ./configure utils_cv_avx512_pclmul_intrinsic_exists=no ...

You might have to also disable other intrinsics, as listed by:

  grep CACHE.*utils_cv.*intrins configure.ac

cheers,
Pádraig



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