I made mistake and changed perl non-threaded version to threaded by unmerge first, change
USE flags to include ithreads and emerge perl again. Now most packages depending on perl are broken. How do I rebuild them?
On way is to use
If you want to rebuild all of them, try something like:
You'll have issues with that if you have packages installed that were removed from the portage tree, so a sync and world update beforehand is a good idea.
For this specific case, you might also want to look at