Bug#919272: libblis2: different threading options need to be installable in parallel

[Dave Love]

Package: libblis2
Version: 0.5.1-1
Severity: important

The combinatorial builds are good (and I hope they're repeated for
openblas), but they need to be installable in parallel, and the default
should be serial because anything else is unsafe.  The Fedora openblas
and blis packages allow that.

Considering some Debian packages:  cp2k wants the serial version (see
cp2k.org), numpy apparently needs pthreads (see the openblas changelog),
and I might want OpenMP for linear algebra-heavy R (absent some
higher-level parallelization, like pbdR).  In some cases, like cp2k, you
might want to be able to enforce a version via the soname or rpath.  In
others, like different usages of R, you might want to switch with
LD_LIBRARY_PATH or LD_PRELOAD in different circumstances.

-- System Information:
Debian Release: 9.6
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable-debug'), (500, 'stable'), (50, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 4.9.0-8-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_GB.utf8, LC_CTYPE=en_GB.utf8 (charmap=UTF-8), LANGUAGE=en_GB:en (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: sysvinit (via /sbin/init)

Versions of packages libblis2 depends on:
ii  libblis2-openmp  0.5.1-1

libblis2 recommends no packages.

libblis2 suggests no packages.

-- no debconf information