ARM Cortex-A7 feature misdetection

Jeffrey Walton noloader at
Mon Feb 5 21:46:17 UTC 2018

On Mon, Feb 5, 2018 at 3:56 PM, Torbjörn Granlund <tg at> wrote:
> nisse at (Niels Möller) writes:
>   What I've done in other neon assembly files is to add a
>     .fpu neon
>   pseudo-op early in the file. Seems less brittle to me than passing the
>   corresponding command line options, in particular for fat builds (i.e.,
>   some files with neon assembly, used at runtime only after some check of
>   available instructions), where one might not want the C compiler to emit
>   any neon instructions.
> If we add support for fat arm builds, then that's what we'll need to do!
> I don't know if it could cause some portability problems to add it.

I was in a similar spot last year. I think Marc's solution is the
recommended one. It sidesteps the problem without putzing with
configuration options, CFLAGS and CXXFLAGS.

Also see



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