@langou : @phcerdan and I will start working on the following

• Do not require Fortran. See

  lapack/CMakeLists.txt

  Line 3 in 9fb29d8

  project(LAPACK Fortran C)

• Add option LAPACK enabled by default (similar to the other option named LAPACKE and CBLAS). Enable Fortran only with LAPACK is on. In a nutshell, enable_language(Fortran) will be called only if LAPACK is ON

• Exclude this code if CMAKE_CONFIGURATION_TYPES is defined

• Update appveyor.yml to test building with LAPACK:BOOL=OFF and LAPACKE:BOOL=ON using generators -G "Visual Studio 14 2015 Win64 (will add VS 2017 later)