[Fedora-packaging] Proposal: Remove BuildRequires: exceptions from the guidelines

[Jason L Tibbitts III]

TL;DR: There's a proposal for nuking the list of BuildRequires
exceptions from the packaging guidelines.

Important note: this is just an idea.  We're not currently changing the
guidelines based on this.  Nothing is set in stone.  It may end up that
nothing happens.  Don't panic.

A couple of times recently, people have floated proposals to the FPC
about removing certain things from the buildroot.  (Specifically, perl
and gcc*.)  And the bottom line for these is that while FPC tries to
maintain a list of BuildRequires: exceptions, this is really up to
releng and whatever rpm happens to pull in at any particular time.

This means that whatever list FPC maintains, it's going to get outdated
eventually, and giving packagers the idea that they don't have to
actually specify all of their dependencies restricts what releng can do
and, perhaps, what dependencies the RPM package can drop without
breaking builds.

So, the generally stated proposal:

I would like to get FPC out of the business of specifying this list of
exceptions, and instead just indicate that packagers should completely
specify their dependencies.

My specific proposal can be seen in
https://fedorahosted.org/fpc/ticket/497; the draft is at
https://fedoraproject.org/wiki/User:Tibbs/BuildReqDraft2.  You can use
the history tab to see the differences between that and the current
guidelines.

Now, the real issue is in what packagers can depend upon.  Obviously you
have RPM and an environment necessary to build a package (which means
you have to have a shell to execute the scripts that make up the RPM
sections, and redhat-rpm-config, and whatever RPM happens to use to
execute %patch, which I guess could be some internal library if the RPM
devs wanted).  But what else?  That's the open question.

The draft currently says:

---
You may assume that you have everything necessary for RPM to function
and process your spec file (so of course RPM is present, along with
redhat-rpm-config and what is necessary for RPM to apply patches, unpack
archives, and run the shell scripts which make up the spec file
sections.) You should not assume any other packages are present, as RPM
dependencies and anything brought into the buildroot by the build system
may change over time.
---

Honestly, I'm not completely satisfied with that but I can't come up
with anything better.  Polite discussion is welcomed and encouraged.

 - J<