On Tue, Mar 15, 2016 at 11:14 AM, Drew Parsons <[email protected]> wrote: > Hi PETSc users and friends, > > I'm thinking to changing the versioned naming scheme used for PETSc > packages in Debian. I'd like to hear if you think that might break > something. > > Up till now the minor version has been embedded in the package name, > e.g. dev package is libpetsc3.6.2-dev, which strictly depends on the > matching version of the library binary package. > > Previously the library package also included the minor version, > e.g. libpetsc3.4.2. But the soname inside the library itself does not > include the minor version. e.g. the current library file > /usr/lib/x86_64-linux-gnu/libpetsc_real.so.3.6.2 has > soname libpetsc_real.so.3.6 (I injected "_real" myself to distinguish > from the version with complex number support). So all 3.6 versions > should be binary compatible, whether 3.6.2 or 3.6.3, assuming upstream > has correctly defined the soname. > > For this reason I removed the minor version from the library package > name, so the package is just libpetsc3.6 not libpetsc3.6.2 or > libpetsc3.6.3. > > But because of the tight dependence of the dev package, > libpetsc3.6.2-dev needs libpetsc3.6 (3.6.2.dfsg1-3+b3), so > libpetsc3.6 (3.6.3.dfsg1-1) won't do. Hence libpetsc3.6.2-dev cannot > currently be installed parallel to libpetsc3.6.3-dev. > > For this reason, I think it might be simplest to just drop the minor > version from the dev package. > > So then libdolfin-dev, for example, would depend on libpetsc3.6-dev > instead of libpetsc3.6.2-dev. > > Now PETSc is installed using the minor version, e.g. separate > directories /usr/lib/petscdir/3.6.2 and /usr/lib/petscdir/3.6.3. So in > principle it is possible to organising the packages to allow parallel > installations. > > But I'm not certain that anything is gained by having parallel > installations for a library with the same soname. It could be done, > e.g. libpetsc3.6-dev could be a virtual package that depends on the > latest libpetsc3.6.x-dev. But would that provide any real benefit? It > seems to me that using libpetsc3.6-dev as the dev package would be > simpler. > > What do you think?
Sounds good to me. Johannes
