lapack only works as shared on Windows

[uilianries]

No description provided.

[uilianries]

lib/1.2.11@conan/stable: Package installed 15cf71dd0a958f4b330128b207351fcfd9ae304f
lapack/3.7.1@conan/stable: WARN: Can't find a 'lapack/3.7.1@conan/stable' package > for the specified settings, options and dependencies:

• Settings: arch=x86, build_type=Release, compiler=Visual Studio, compiler.runtime=MT, compiler.version=12, os=Windows
• Options: shared=True, visual_studio=True, zlib:minizip=False, zlib:shared=False
• Dependencies: zlib/1.2.11@conan/stable
• Package ID: c35253a749b74cac0d2f707564e38ca309001ad0

@danimtb is not possible forcing lapack:shared=True, because when relapack is built as static library, it needs compiler.runtime=MT

Possible options:

• Exclude MT support from Relapack
• Exclude static library support from Relapack

[danimtb]

It makes sense for visual studio. The current binary matrix is doesn't have VS packages at all, so better something than nothing:

Thanks

[SSE4]

@danimtb please fix CI errors

[danimtb]

Sorry, I have no idea what is the status of this. @uilianries could you check, please? What was the purpose of this PR?

[uilianries]

lapack support for Visual Studio is not working.

When building lapack with mingw for Visual Studio, the test package uses mingw:
https://ci.appveyor.com/project/ConanCIintegration/conan-lapack/build/job/o6jwdt5f8kid1hcw#L10040

To build relapack with Visual Studio, we need to force lapack as shared library cause it restriction, but it not enough. As it was built by mingw, the entrypoint is not found by Visual Studio and I'm afraid we need to import some mingw libs (e.g. libm).

On the other hand, we could use the specific version for Windows: https://icl.cs.utk.edu/lapack-for-windows/lapack/
I'm not sure about the compatibility, because they offer the version 3.1.1

Also, there is a project called clapack:

The CLAPACK library was built using a Fortran to C conversion utility called f2c. The entire Fortran 77 LAPACK library is run through f2c to obtain C code, and then modified to improve readability. CLAPACK's goal is to provide LAPACK for someone who does not have access to a Fortran compiler.

I don't if is it possible replacing lapack by clapack for this case.

Opinions ?