A revdep-rebuild is necessary if this lib is upgraded, the ebuild should add some ewarn about that. Reproducible: Always
revdep-rebuild should be run after almost every library upgrade... I think you can consider your-self always warned... :) You can create a simple script which revdep-rebuild after each emerge... This will probably help keeping system integrity.
(In reply to comment #1) > revdep-rebuild should be run after almost every library upgrade... I think you > can consider your-self always warned... :) That's right, had have the similar issues with libexif. OTOH what's about send a warning always if a lib is updated ?
You can try to file a new bug against portage... But I don't think you will have much luck... :( We can add something like: EBUILD_FLAGS="library" so that portage will be able to notify users.. But best while package is unmerged and a file is removed, it will be searched for dependent packages and auto remerge them.