When a checkout fails, it doesn't stop properly, but tries to continue, so it's hard to find out what really went wrong. (just a little "|| die" would do the trick). Reproducible: Always
Created attachment 237649 [details, diff] fix for git.eclass
+1 This one-liner fix is so important to for development use of Gentoo, though may not be so for the official portage tree.
git.eclass is obsoleted by git-2 eclass. It is more sanely separated and has dies on all proper places :)