lapack doesn't properly export library name on OS X

[ahmadia]

on OS X, it will be liblapack.dylib, the name is liblapack.so currently. Should be a simple fix.

[chvillanuevap]

For example, ScaLAPACK is built with:

extends: [cmake_package]

dependencies:
  build: [lapack, mpi]

sources:
- url: http://www.netlib.org/scalapack/scalapack.tgz
  key: tar.gz:br2k5ltjb7s64tnxsjxutroqxnu44cpo

defaults:
  # lib/libscalapack.so contains hard-coded path
  relocatable: false

build_stages:
- name: configure
  when compiler == 'gcc':
      extra: ['-D CMAKE_Fortran_FLAGS_RELEASE:STRING="-O3 -fPIC -march=native -ffast-math -funroll-loops"',
              '-D BUILD_TESTING:BOOL=OFF',
              '-D BUILD_SHARED_LIBS:BOOL=ON',
              '-D LAPACK_LIBRARIES:STRING="${LAPACK_DIR}/lib/liblapack.so"',
              '-D BLAS_LIBRARIES:STRING="${LAPACK_DIR}/lib/libblas.so"',
              ]
  when compiler != 'gcc':
      extra: ['-D BUILD_TESTING:BOOL=OFF',
              '-D BUILD_SHARED_LIBS:BOOL=ON',
              '-D LAPACK_LIBRARIES:STRING="${LAPACK_DIR}/lib/liblapack.so"',
              '-D BLAS_LIBRARIES:STRING="${LAPACK_DIR}/lib/libblas.so"',
              ]
  build_in_source: true

- name: setup_builddir
  mode: override
  bash: |

However, on OS X the library is named liblapack.dylib as you said. Should I just override the build stage in my profile? Or is there a generic way of handling library names?

[certik]

I think the solution is along these lines: https://github.com/hashdist/hashstack/pull/709#issuecomment-88595480, the lapack implementation should export couple environment variables about how to link it, paths to the libraries (i.e. .so or .dylib, or .dll) and so on. Then packages like scalapack just use those environment variables instead of hardwiring ${LAPACK_DIR}/lib/liblapack.so.