[CMake] FindLAPACK/FindBLAS require Fortran compiler. Why?

[Alin M Elena]

Hi Marcel,

There are two reasons for that.
1. The way in which FindBlas and Lapack are working. They check that actually 
you can link against this libs, by writing a small Fortran call program. 
2. They are for Fortran use projects. Calling fortran functions from C/C++, in 
a portable way, is not as simple as it looks.

As the modules do a little bit more than just finding some names, we decided 
some time ago that is better to keep Fortran versions FindBlas/Lapack and in 
future if necessary to add C versions.

As a note, if you are interested in mixing C/C++/Fortran I will recommend you 
the iso_c_binding module, from Fortran 2003 standard as a portable, standard 
way of doing it.

regards,

Alin

-- 
 ______________________________________________________________________
 "If the Universities will not study useless subjects, who will?"
                             G. F. FitzGerald, Nature, 45/46, 392 (1892)
 ______________________________________________________________________
 Mr  Alin M ELENA
 Irish Centre for High-End Computing -- www.ichec.ie
 The Design Tower, Trinity Technology & Enterprise Campus
 Grand Canal Quay,  Dublin 2, Ireland
 Tel:   +353 (0) 1 5241608 ext 29
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 http://alin.elenaworld.net
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 alinm.elena at gmail.com
 ______________________________________________________________________
On Tuesday 07 July 2009 09:31:57 cmake-request at cmake.org wrote:
> Message: 5
> Date: Tue, 07 Jul 2009 10:11:21 +0200
> From: "Marcel Loose" <loose at astron.nl>
> Subject: [CMake] FindLAPACK/FindBLAS require Fortran compiler. Why?
> To: <cmake at cmake.org>
> Message-ID: <4A531F4902000020000062F6 at server7.nfra.nl>
> Content-Type: text/plain; charset=US-ASCII
>
> Hi all,
>
> I noticed that FindLAPACK and FindBLAS require that you enable Fortran
> as language, which causes CMake to check for a working Fortran
> compiler.
> IMHO, you only need the fortran runtime libraries, cause you're only
> linking against the Lapack/Blas libraries. Most Linux distro's have
> separate packages for compiler and runtime libraries.
>
> Is there a good reason for FindLAPACK and FindBLAS to require a working
> Fortran compiler?
>
> Best regards,
> Marcel Loose.