Multiple spurious dependencies that actually are not there

[Aleksej Lebedev <root%zta.lk@localhost>]

Hi, everyone!

I think I found two kinds of bugs (I guess) somewhere in 
mk/pkgformat/pkg.

When building some packages on Linux (some on Darwin and I guess other 
on other platforms too), for example devel/glib2, the script that 
creates metadata, specifically ./+BUILD_INFO, picks up some spurious 
dependencies from the host system that are not actually needed.

For example I have /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0 in the 
list of dependencies for devel/glib2. If I delete the package, then 
remove the system libglib (apt-get remove libglib2.0) and rebuild glib2 
from pkgsrc, the dependency disappears.

Normally it's not a problem because I tend to build packages on a really 
minimalistic chroot'd ubuntu environment.
But it turned out that libglib2 is part of ubuntu-minimal which I 
automatically have after debootstrap finishes.

Even more upsetting is the fact that devel/libidn2 (needed for www/curl) 
is created with spurious dependency on host's libidn, which is needed by 
init.

I found out about it when I tried to install freshly built packages on 
docker image that contains pretty much nothing at all (but in fact 
satisfy all real dependencies of pkgsrc packages).

This was the first kind of bug.

The other one is related but a bit different. Besides the dependencies 
on libs from the host system there are sometimes appear deps on libs 
that are located in the temporary destdir where the package is 
stage-installed.
I.e. +BUILD_INFO contains REQUIRES= entries that point to 
/var/tmp/pkgsrc-obj/devel/libidn2/work/.destdir/pkg/lib/...
(I can provide more details if needed.)

I am quite busy with my full-time job, so I didn't spend enough time to 
figure out where exactly the bug is. So I decided to post it here and 
hope maybe somebody will help me out.

--
Aleksej Lebedev