Re: OpenBLAS

[Federico Beffa]

On Sun, Oct 9, 2016 at 2:19 PM, Pjotr Prins <address@hidden> wrote:
> On Sat, Oct 08, 2016 at 10:13:39PM +0200, Federico Beffa wrote:
>> Hi,
>>
>> I'm wondering why our OpenBLAS package is built with the flag
>> "NO_LAPACK=1". It is my understanding that with this optional flag
>> OpenBLAS doesn't include LAPACK, while without this flag and by
>> default it does include the LAPACK functions.  In the latter case
>> OpenBLAS could be used by a larger number of packages which do require
>> LAPACK functions.
>>
>> https://github.com/xianyi/OpenBLAS/issues/203
>
> NO_LAPACK=0 does not use external libs. NO_LAPACK=1 uses external
> liblapack. They both cover LAPACK functionality.
>
> NO_LAPACK=1 is the conservative choice - it still is what most
> software has been developed against today.
>
> OpenBLAS has merged LAPACK code and they have been changing things,
> claiming their version is better performing. But since it is less well
> tested, new bugs are quite possible. I have hit at least one OpenBLAS
> bug, so far.

Thanks for the info.  OpenBLAS is now around since several years and
has gained in popularity. I'm sure that any bug report will be
addressed timely.

In any case, I find that with "NO_LAPACK=1" hmatrix can't use it
http://hackage.haskell.org/package/hmatrix

>
> Personally I think we should have both options in Guix, but we should
> probably keep defaulting to NO_LAPACK=1.

For the moment I will use LAPACK.  If your proposal will happen I will switch.

Thanks for the reply,
Fede