All, the problem is the following.
Back when deal.II was built [1] the location of the MPI headers was at MPI_INCLUDE_DIRS: /usr/lib/openmpi/include/openmpi;[...];/usr/lib/openmpi/include this was found during configure time and recorded in the deal.IIConfig.cmake file that gets installed to /usr/share/cmake/deal.II/deal.IIConfig.cmake Now, this location changed on disc [2] for the newest openmpi version in stretch - it is now: MPI_INCLUDE_DIRS = /usr/lib/x86_64-linux-gnu/openmpi/include/openmpi;[...];/usr/lib/x86_64-linux-gnu/openmpi/include (As correctly picked up by configuring the source package.) We have to recompile deal.II yet another time to reflect these changes in the configuration. :-/ Best, Matthias [1] https://buildd.debian.org/status/fetch.php?pkg=deal.ii&arch=amd64&ver=8.4.2-2&stamp=1481120232&raw=0 [2] openmpi (2.0.2~git.20161225-8) unstable; urgency=medium * Multiarch support. Closes: #833728, #842881. -- Alastair McKinstry <mckins...@debian.org> Sat, 17 Dec 2016 14:17:24 +0000 -- debian-science-maintainers mailing list debian-science-maintainers@lists.alioth.debian.org http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/debian-science-maintainers