Corresponding USE statements should be advised in all cases when such USE is equivalent to dependency.
devel/bison is one example I encountered, please make sure the rest are also handled.
This has been added to 2.17.7.
A commit references this bug:
Date: Wed Mar 29 15:28:56 UTC 2017
New revision: 437207
Update to 2.17.7.
* Fold in the same removal of the obsolete HTTP-only warning
* Add support for checking for direct dependency on bison, fmake, and libexecinfo. 
PR: 216268