Create shared libraries lib{blas,lapack}.so.3

Create shared libraries lib{blas,lapack}.so.3

Forwarded: not-needed
Last-Update: 2020-07-31

* It is done so that duplicate code with libopenblas.so.0 is kept as low as
  possible. Only the symbols from the external BLAS/LAPACK API are incorporated
  in the shared libraries. The rest is obtained by dynamic linking against
  libopenblas.so.0. This also gives access to some extra OpenBLAS symbols, in
  order to differentiate it at runtime from other BLAS implementations (see
  #960728).
  The -rpath,'$ORIGIN' is there to ensure that the OpenBLAS flavour used is
  the one selected in the lib{blas,lapack}.so.3 alternative, and not the one
  selected in the libopenblas.so.0 alternative.
* See also override_dh_shlibdeps in debian/rules
* Also order the files when calling `ar' or $(CC), to make
  the build reproducible (see #824639)
* Also link the shared blas and lapack against gomp (see #945791)
Last-Update: 2020-07-31
Gbp-Pq: Name shared-blas-lapack.patch