# revdep-rebuild -p
 * Configuring search environment for revdep-rebuild

 * Checking reverse dependencies
 * Packages containing binaries and libraries broken by a package update
 * will be emerged.

 * Collecting system binaries and libraries
 * Generated new 1_files.rr
 * Collecting complete LD_LIBRARY_PATH
 * Generated new 2_ldpath.rr
 * Checking dynamic linking consistency
[ 100% ]                 
 *   broken /usr/lib/libgio-2.0.so.0 (no version information available)
 *   broken /usr/lib/libxml2.so.2 (no version information available)
 *   broken /usr/lib/perl5/5.12.4/i686-linux/auto/Compress/Raw/Zlib/Zlib.so (no version information available)
 *   broken /usr//lib/libxml2.so.2 (no version information available)
 * Generated new 3_broken.rr
 * Assigning files to packages
 *   /usr//lib/libxml2.so.2 -> dev-libs/libxml2
 *   /usr/lib/libgio-2.0.so.0 -> dev-libs/glib
 *   /usr/lib/libxml2.so.2 -> dev-libs/libxml2
 *   /usr/lib/perl5/5.12.4/i686-linux/auto/Compress/Raw/Zlib/Zlib.so -> dev-lang/perl
 * Generated new 4_raw.rr and 4_owners.rr
 * Cleaning list of packages to rebuild
 * Generated new 4_pkgs.rr
 * Assigning packages to ebuilds
 * Generated new 4_ebuilds.rr
 * Evaluating package order
 * Generated new 5_order.rr
 * All prepared. Starting rebuild
emerge --complete-graph=y --oneshot  --pretend dev-lang/perl:0 dev-libs/glib:2 dev-libs/libxml2:2

These are the packages that would be merged, in order:

Calculating dependencies            ... done!    
[ebuild   R    ] dev-lang/perl-5.12.4-r1 
[ebuild   R    ] dev-libs/libxml2-2.7.8-r1 
[ebuild   R   ~] dev-libs/glib-2.30.0 
 * Now you can remove -p (or --pretend) from arguments and re-run revdep-rebuild.