Description of problem:
Development packages which provide .pc files often require .pc files (and
headers, and libraries) provided by other development packages.  Fedora Core's
pkgconfig package (at least as of 1:0.15.0-6) can be used to query this
information.  It would be useful if the RPM recorded this dependency information
in packages so that it could be tracked.

Version-Release number of selected component (if applicable):
4.4.1-21

How reproducible:
Always

Steps to Reproduce:
1. Install pygtk2-devel, uninstall glib2-devel.
2. Attempt to compile anything using pygtk2's pygobject-2.0.pc file.
3. Scratch your head in confusion.
  
Actual results:
Failure to link.

Expected results:
Successful link, or a dependency between pygtk2-devel and glib2-devel at least
getting in your way.

Additional info:
Scripts for extracting requires/provides information are in bugzilla as
attachment #112736 [details] and attachment #112737 [details], attached to bug #153936.