Package: src:ncl Version: 6.3.0-10 Severity: serious ncl (6.3.0-10) unstable; urgency=medium * Preferentially use openblas not blas
This is implemented as: Build-Depends: ... libopenblas-dev | libblas-dev, This prevents your package from being built on the architectures where OpenBLAS is not available: https://buildd.debian.org/status/package.php?p=ncl The autobuilders always pick the first choice only, to prevent changed builds when a build dependency is temporarily not installable on unstable. You must state in the build dependencies explicitely on which architectures libopenblas-dev is used instead of libblas-dev. The severity is based on the fact that "package builds no longer on an architecture where it was previously built" is a FTBFS.
