Splitting libHYPRE.so into sublibs ================================== The entire HYPRE library libHYPRE.so, taken as a single monolithic library, is quite large (approx. 6 MB with symbols stripped). Debian has therefore split HYPRE into sublibraries to bring the size of each sublibrary into line with other libraries. Specifically, the FEI component is split into a separate library. Due to circular dependencies between other components, we are not able split other components out into separate sublibraries. Starting from HYPRE 2.15.1, the sublibraries are libHYPRE_core.so libHYPRE_FEI.so which you may link with '-lHYPRE_FEI -lHYPRE_core'. If you do not use FEI then you may save space by linking only against -lHYPRE_core. libHYPRE.so is provided as a "dummy" library which is dynamically linked to libHYPRE_core.so and libHYPRE_FEI.so. Library version, soname and package name ======================================== HYPRE does not provide ABI backwards compatibility. The ABI might change, even between patch version updates (Z in X.Y.Z). This makes it inconvenient to follow the usual Debian practice of creating a library binary package libhypre-X.Y containing the library for a given ABI soname. The package would have to pass through the NEW queue as a new package each time, even for a minor patch update. For this reason, starting with 2.18.1, the library binary package is provided as libhypre without the soname version embedded in the name. Version dependency is enforced via a strict shlibs patch version dependency in the shlibs file, libHYPRE_core __HYPRE_VERSION__ libhypre (>= __HYPRE_VERSION__), libhypre (<< __HYPRE_VERSION_NEXT__) This practice of strict shlibs dependency is not normally done since it impedes transition of packages into testing: all dependent packages need to be rebuilt against the new library version and transition at the same time. For hypre this is expected to be less of an inconvenience than the inconvenience of traversing the NEW queue with each version update. There are only 2* dependent packages: petsc (*and slepc) sundials