Add setup.py hooks to disable AVX2, SSE2 or C extensions altogether

[alimanfoo]

Resolves #24.

[FrancescAlted]

FWIW, I am afraid that just avoiding AVX2 instructions in Blosc is not enough. Unless I am missing something, you are not passing any flag for the compiler so as to prevent AVX2 instructions when compiling the Cython extension.

[alimanfoo]

I thought AVX2 will only be used if the compiler has -mavx2? This option is only included in the compile args if AVX2 is detected and DISABLE_NUMCODECS_AVX2 is not set... https://github.com/alimanfoo/numcodecs/blob/master/setup.py#L83

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On Wed, Mar 1, 2017 at 2:13 PM, Francesc Alted ***@***.***> wrote: FWIW, I am afraid that just avoiding AVX2 instructions in Blosc is not enough. Unless I am missing something, you are not passing any flag for the compiler so as to prevent AVX2 instructions when compiling the Cython extension. — You are receiving this because you modified the open/close state. Reply to this email directly, view it on GitHub <https://github.com/alimanfoo/numcodecs/pull/26#issuecomment-283350279>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAq8Qj5nO3GFj0r3j_OAFikB7TvYkIouks5rhXz3gaJpZM4MPmBv> .

-- Alistair Miles Head of Epidemiological Informatics Centre for Genomics and Global Health <http://cggh.org> The Wellcome Trust Centre for Human Genetics Roosevelt Drive Oxford OX3 7BN United Kingdom Email: alimanfoo@googlemail.com Web: http://purl.org/net/aliman Twitter: https://twitter.com/alimanfoo Tel: +44 (0)1865 287721

[FrancescAlted]

Not completely sure about that. To be sure, I would add -mno-avx2.

[FrancescAlted]

But the -mno-avx2 flag would be useful only in case you want to produce binaries for distribution (alas, conda-forge or wheels).

[alimanfoo]

OK, thanks for the info, appreciated.

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On Wed, Mar 1, 2017 at 3:43 PM, Francesc Alted ***@***.***> wrote: But the -mno-avx2 flag would be useful only in case you want to produce binaries for distribution (alas, conda-forge or wheels). — You are receiving this because you modified the open/close state. Reply to this email directly, view it on GitHub <https://github.com/alimanfoo/numcodecs/pull/26#issuecomment-283376517>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAq8QpE_CYyAdkmgSLmwhxioUBHJIZjwks5rhZIxgaJpZM4MPmBv> .

-- Alistair Miles Head of Epidemiological Informatics Centre for Genomics and Global Health <http://cggh.org> The Wellcome Trust Centre for Human Genetics Roosevelt Drive Oxford OX3 7BN United Kingdom Email: alimanfoo@googlemail.com Web: http://purl.org/net/aliman Twitter: https://twitter.com/alimanfoo Tel: +44 (0)1865 287721

[alimanfoo]

For reference I made a new PR (#27) which uses -mno-avx2 if DISABLE_NUMCODECS_AVX2 is set.