Ubuntu LTS 16.04, libmpich-dev:i386, wrong dependencies in package

[Dandy Eschricht]

Dear Maintainers,

i am trying to install libmpich-dev:i386 with the following outcome:
root at ubuntu:~/MPICH_1604# apt-get install libmpich-dev:i386
...
The following packages have unmet dependencies:
 libmpich-dev:i386 : Depends: gfortran:i386 but it is not going to be installed
                     Depends: g++:i386 but it is not going to be installed
E: Unable to correct problems, you have held broken packages.


Please note, that gfortran:i386 and g++:i386 are neither required to use the package, nor do they appear in the dependencies list.
Details on the package libmpich-dev, i put at the end of this mail.

I have the following packages installed (which allows me to build 32- and 64-bit applications using gcc, g++ and gfortran):
root at ubuntu:~/MPICH_1604# dpkg --get-selections | grep gfortran
gfortran					install
gfortran-5					install
gfortran-5-doc					install
gfortran-5-multilib				install
gfortran-doc					install
lib32gfortran-5-dev				install
lib32gfortran3					install
libgfortran-5-dev:amd64				install
libgfortran3:amd64				install
libx32gfortran-5-dev				install
libx32gfortran3					install

root at ubuntu:~/MPICH_1604# dpkg --get-selections | grep g++
g++						install
g++-5						install

Please mind that after a force install via:
root at ubuntu:~/MPICH_1604# apt-get download libmpich-dev:i386
and
root at ubuntu:~/MPICH_1604# dpkg --force-depends -i libmpich-dev_3.2-6build1_i386.deb
all required files to compile and link are available.
mpich-packages installed now:
root at ubuntu:~/MPICH_1604# dpkg --get-selections | grep mpich
libmpich-dev:i386				install
libmpich12:i386					install
mpich:i386					install
mpich-doc					install

and building mpich-applications works fine using either:
mpicc.mpich -o ../bin/hello hello.c -m32
or
gcc -o ../bin/hello hello.c -m32 -I/usr/include/mpich/ -L/usr/lib/i386-linux-gnu -lmpich
or
mpif90.mpich -cpp -o ../bin/hello hello.f90 -m32

I do not know whether the problem is on the apt side.
If apt translates the dependency gfortran to gfortran:i386 because the package is :i386 then the bug is in apt.
Please let me know if should file a bug for apt.

Best Regards,
Dandy


root at ubuntu:~/MPICH_1604# apt-cache show libmpich-dev:i386
Package: libmpich-dev
Priority: extra
Section: universe/libdevel
Installed-Size: 6891
Maintainer: Ubuntu Developers <ubuntu-devel-discuss at lists.ubuntu.com>
Original-Maintainer: Debian Science Maintainers <debian-science-maintainers at lists.alioth.debian.org>
Architecture: i386
Source: mpich
Version: 3.2-6build1
Replaces: libmpich1.0-dev, libmpich2-dev, libmpl-dev, libopa-dev
Depends: gfortran, g++, libcr-dev, libmpich12 (= 3.2-6build1), libc6 (>= 2.7), libcr0 (>= 0.8.2)
Recommends: mpich (= 3.2-6build1)
Breaks: libmpich1.0-dev, libmpich2-dev, libmpl-dev, libopa-dev
Filename: pool/universe/m/mpich/libmpich-dev_3.2-6build1_i386.deb
Size: 1182728
MD5sum: f38849c1b456fc3633d499a1e1a77038
SHA1: f30dc911c5d160a313fb304f4249773cc8c65e8f
SHA256: f441e1e1c1da783a877733fef6f62dc3189bc5a810b2449813442d9225faffa0
Description-en: Development files for MPICH
 MPICH is a high-performance and widely portable implementation of the
 Message Passing Interface (MPI) standard (both MPI-1 and MPI-2). It
 efficiently supports different computation and communication platforms
 including commodity clusters, SMPs, massively parallel systems, and
 high-speed networks.
 .
 This package includes the MPICH headers and static libraries, as well
 as the compiler wrappers needed to build MPICH programs.
Description-md5: 3c6557ee2e0f267fcc0f7b3491d99d3c
Homepage: http://www.mpich.org/
Bugs: https://bugs.launchpad.net/ubuntu/+filebug
Origin: Ubuntu