Comment # 46 on bug 1177260 from Egbert Eich

(In reply to Stefan Br���ns from comment #45)
> 
> I think for Leap/SLE 15, the old SONAME is actually the better option.
> Otherwise, you need a full rebuild (at least the parts which directly or
> indirectly use openblas), othwerwise you may end up with a binary which
> links to openblas.so and openblas_pthreads.so at the same time.
> 
> If you don't do a rebuild, you may end up with a user using the openmp
> openblas.so via update alternatives, and openblas_pthreads.so. I a quite
> sure this will not work.

Well, the old SONAME scheme would require even more %if ... %endif mess in the
spec file. 
All standard binaries are built for openblas_pthreads.so.0. If we provide a
compatibility link, why would a user end up with two openblas libraries?
Because  of a binary requiring two libs that themselves require openblas - one
of which has been rebuilt and one hasn't?