[Debian-med-packaging] Bug#1146883: -dev package missing dependencies needed by pkg-config

[Benjamin Gilbert]

Package: openslide
Version: 4.0.1+dfsg-1
Severity: serious

After installing pkgconf and libopenslide-dev in a fresh sid container:

# pkg-config --libs openslide
Package glib-2.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `glib-2.0.pc'
to the PKG_CONFIG_PATH environment variable
Package 'glib-2.0', required by 'openslide', not found
Package 'gio-2.0', required by 'openslide', not found
Package 'gobject-2.0', required by 'openslide', not found
Package 'cairo', required by 'openslide', not found
Package 'libxml-2.0', required by 'openslide', not found
Package 'libtiff-4', required by 'openslide', not found
Package 'libopenjp2', required by 'openslide', not found
Package 'libjpeg', required by 'openslide', not found
Package 'libpng', required by 'openslide', not found
Package 'zlib', required by 'openslide', not found
Package 'libzstd', required by 'openslide', not found

pkg-config is the supported way to determine how to link with
OpenSlide, and pkg-config requires the .pc files mentioned in
openslide.pc's Requires.private to exist, so libopenslide-dev isn't
useful without the -dev packages that provide these files.  By policy
3.5, libopenslide-dev must therefore depend on those packages.

A couple such dependencies were added in #1146800; see previous
discussion there.