Variable: semanticdb-mode-hook
semanticdb-mode-hook is an alias and customizable for
global-semanticdb-minor-mode-hook, defined in db-mode.el.gz.
Value
(semantic-imenu-semanticdb-hook)
Documentation
Hook run after entering or leaving global-semanticdb-minor-mode(var)/global-semanticdb-minor-mode(fun).
No problems result if this variable is not bound.
add-hook automatically binds it. (This is true for all hook variables.)