Bug#980751: petsc: breaks multiple autopkgtests: undefined reference to 'MPIU_SUM'

[Drew Parsons]

Source: dolfin
Followup-For: Bug #980751

Hard to say what went wrong here, to be honest.  As far as I can tell
dolfin is innocent in any case.  The problem was triggered in slepc
and fixed by rebuilding slepc.  On the face of it the problem is in
the dependency relationship between slepc and openmpi.

There were a lot of updates to the openmpi suite (including pmix and
ucx) in the past month. The openmpi library transition was already
declared to libopenmpi3 (>= 4.1.0). It must be some subtlety in the
handling of MPIU_SUM in openmpi 4.1.0, though it doesn't make sense
that pmix or ucx would affect that.

In short, buggered if I know.
https://youtu.be/BmRUJGRwkj0?t=111