Re: 01/01: gnu: fftw: Build SIMD codelets.

[Mark H Weaver <mhw@netris.org>]

Hi Eric,

ericbavier@centurylink.net (Eric Bavier) writes:

> bavier pushed a commit to branch core-updates
> in repository guix.
>
> commit 65bb22796f854cbc3eae053a80b1d64365dad376
> Author: Eric Bavier <bavier@cray.com>
> Date:   Fri Apr 6 10:53:06 2018 -0500
>
>     gnu: fftw: Build SIMD codelets.
>     
>     * gnu/packages/algebra.scm (fftw)[arguments]: Remove 'no-native phase; use
>     configure cache value instead.  Add configure flags for SIMD codelets.
>     (fftwf)[arguments]: Add neon configuration flag for 32-bit arm.
>     (fftw-avx): Remove variable.

[...]

> @@ -560,7 +569,10 @@ cosine/ sine transforms or DCT/DST).")
>      (arguments
>       (substitute-keyword-arguments (package-arguments fftw)
>         ((#:configure-flags cf)
> -        `(cons "--enable-float" ,cf))))
> +        (if (string-prefix? "arm" (or (%current-target-system)
> +                                      (%current-system)))
> +            `(cons "--enable-neon" ,cf)
> +            cf))))

Did you intend to remove the "--enable-float" configure flag in fftwf?
You didn't mention this change in the commit log.

The description of fftwf appends "Single-precision version" to the
description from fftw, but since your commit above, the fftw and fftwf
packages are identical except on armhf, as far as I can tell.  On armhf,
the build now fails with "configure: error: NEON requires single
precision".

  https://hydra.gnu.org/build/2674813/nixlog/1/tail-reload

Can you take a look?

      Mark