To Require or not to Require?

[Michael Schwendt]

On Thu, 11 Aug 2011 16:13:48 +0200, AS (Andreas) wrote:

> > No external package can build with new features of the new "foo-libs" package
> > prior to making that package available in the buildroot.
> 
> How is the contents of the buildroot relevant to "yum install bar"?

"bar" has been built with an older libfoo. The newer libfoo isn't strictly
needed, because any available package providing the needed ABI will suffice.

"foo", on the other hand, would be first to actually use the very latest
API extensions. Not always, but often (and more often that many ordinary
app bug-fix updates that have build dependencies on much older lib versions).
The explicit dep on the lib pkg is _not_ mandatory.

> > If "foo" is the base package of "foo-libs", and this -libs package has
> > added symbols needed by programs in package "foo", an older release
> > of "foo-libs" would not suffice. On the contrary, all programs
> > linked with an older foo library will continue to work.
> 
> How is that different from the above?

Well, feel free to toggle on/off the explicit dep whenever you think
that's appropriate. Have fun with the typical breakage when subpackages
get out of sync with base packages (such as in the case of a patched
-devel package not depending on the patched library base package -- which
has resulted in a lot of head-scratching when rebuilds against a new
-devel package didn't fix an issue because the fixed library wasn't
installed yet). Only a full "yum update" before and after any "yum
install" action will avoid many issues with dependencies.