$ ./get-completions /usr/share/bash-completion | ./completion-qa-check.py | grep git gitk: missing completion symlink for command (declared in /usr/share/bash-completion/git) Long story short, you need to install: gitk -> git symlink in $completionsdir to get 'gitk' completion autoloaded properly.
+ 11 Oct 2014; Michał Górny <mgorny@gentoo.org> git-2.1.2.ebuild, + git-9999-r1.ebuild, git-9999-r2.ebuild, git-9999-r3.ebuild, git-9999.ebuild: + Install bash completion alias for gitk command, bug #521168.