Dear Maintainer,

prime-phylo fails to build on armhf platform due to the disabled openmpi-bin
and libopenmpi-dev in mpi-defaults 1.17:
---
- libopenmpi-dev (>= 1.4.3-2.1) [alpha amd64 arm64 armel armhf hppa hurd-amd64
hurd-i386 i386 ia64 kfreebsd-amd64 kfreebsd-i386 loong64 m68k mips mips6
4el mipsel powerpc powerpcspe ppc64 ppc64el riscv64 s390x sh4 sparc64 x32],
- openmpi-bin (>= 1.4.3-2.1) [alpha amd64 arm64 armel armhf hppa hurd-amd64
hurd-i386 i386 ia64 kfreebsd-amd64 kfreebsd-i386 loong64 m68k mips mips64el
 mipsel powerpc powerpcspe ppc64 ppc64el riscv64 s390x sh4 sparc64 x32],
-# libmpich-dev [],
-# mpich []
+ libopenmpi-dev (>= 1.4.3-2.1) [alpha amd64 arm64 hurd-amd64 ia64 kfreebsd-
amd64 loong64 mips64el ppc64 ppc64el riscv64 s390x sparc64],
+ openmpi-bin (>= 1.4.3-2.1) [alpha amd64 arm64 hurd-amd64 ia64 kfreebsd-amd64
loong64 mips64el ppc64 ppc64el riscv64 s390x sparc64],
+ libmpich-dev [armel armhf hppa hurd-i386 i386 kfreebsd-i386 m68k mips mipsel
powerpc powerpcspe sh4 x32],
+ mpich [armel armhf hppa hurd-i386 i386 kfreebsd-i386 m68k mips mipsel powerpc
powerpcspe sh4 x32]
---

This causes the following error:
/usr/bin/ld: ../../libraries/prime/libprime-phylo.so: undefined reference to
`boost::mpi::communicator::operator ompi_communicator_t*() const'
/usr/bin/ld: ../../libraries/prime/libprime-phylo.so: undefined reference to
`boost::mpi::detail::mpi_datatype_map::set(std::type_info const*,
ompi_datatype_t*)'
collect2: error: ld returned 1 exit status
The failing build log[1]

[1] https://launchpadlibrarian.net/742981238/buildlog_ubuntu-oracular-
armhf.prime-phylo_1.0.11-12_BUILDING.txt.gz

Hi,

Vladimir Petko, on 2024-08-13:

If I understand the situation correctly, prime-phylo expects for
the boost build to provide openmpi support specifically.  This
is not a matter of pulling more packages in prime-phylo depends:
the build failure persists anyway.  This looks more to be a
matter of building boost with openmpi support for 32-bit archs.

I see three non-exclusive courses of action.  First option would
be to adjust prime-phylo so it builds for generic mpi and has no
specific expectation for openmpi (from quick glimpse in the
source code, this looks very involved, and upstream shown no
activity since introduction of the package in 2012).  Second
option would be to bring back openmpi builds in boost (I don't
know whether this is feasible or not).  Third option would be to
stop supporting 32-bit platforms (the present ftbfs bug probably
should have been serious in the first place, important severity
could be parsed as an invitation to proceed to the removal).

I'll request the removal to buy us some time in case someone
wants to implement one of the two first options; the build issue
is currently preventing migration of the resolution of RC bug
#1075397.

Have a nice day,  :)