Bug#918919: freefem++: build does not detect PETSc

[Drew Parsons]

Package: freefem++
Version: 3.61.1+dfsg1-4
Severity: normal

freefem++ now Build-Depends on petsc dev packages.  But the
configuration can't detect it, it doesn't know which directory to look
in.

The default petsc directory is /usr/lib/petsc (links to the latest
petsc-real unless an alternative is set manually) but the freefem++
configuration doesn't look there (odd, given the large number of
directories it does look in).

But in your case if you want to specify petsc-complex (for the generic
case, without specifying the petsc version), you'll to get
it to look in /usr/lib/petscdir/complex.  Except I haven't created
that symlink yet, sorry about that. I'll upload another petsc version
for it.  

To keep it symmetric, look then for the real version in
/usr/lib/petscdir/real rather than /usr/lib/petsc. (The idea of
/usr/lib/petsc is to represent the default petsc for when you don't
actually care what the default is, real or complex or which version)

Note that I'd expect client packages to select either petsc-real or
petsc-complex.  I wouldn't expect freefem++ to be able to use both
from the same freefem++ binary, unless they've done something
particularly funky with their petsc handling.  If you want both you
probably have to run 2 separate builds for 2 binaries, freefem++-real
and freefem++-complex.

We don't yet have other packages using petsc-complex to compare with,
apart from slepc which builds separate real and complex libs.  dolfin
will use petsc-complex in the future, but that is not ready yet.

Separately, I've uploaded petsc 3.10.3+dfsg1-4 which provides dummy
packages libpetsc-real-dev and libpetsc-complex-dev that you will be
able to use in Build-Depends.  This will save having to update the
petsc version whenever there is a petsc upgrade.  (petsc-real was
already provided by petsc-dev but I hadn't previously created a
versionless dummy package for petsc-complex). It's waiting in the NEW
queue.

Drew

-- System Information:
Debian Release: buster/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.19.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_AU.UTF-8, LC_CTYPE=en_AU.UTF-8 (charmap=UTF-8), LANGUAGE=en_AU.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages freefem++ depends on:
ii  freeglut3                        2.8.1-3
ii  libarpack2                       3.6.3-1
ii  libatlas3-base [libblas.so.3]    3.10.3-7+b1
ii  libblas3 [libblas.so.3]          3.8.0-2
ii  libc6                            2.28-4
ii  libgcc1                          1:8.2.0-14
ii  libgl1                           1.1.0-1
ii  libglu1-mesa [libglu1]           9.0.0-2.1
ii  libhdf5-103                      1.10.4+repack-8
ii  libopenblas-base [libblas.so.3]  0.3.5+ds-1
ii  libopenmpi3                      3.1.3-9
ii  libstdc++6                       8.2.0-14
ii  libumfpack5                      1:5.4.0+dfsg-1

freefem++ recommends no packages.

freefem++ suggests no packages.

-- no debconf information