The attached patch should allow sys-libs/ncurses to only build shared libs (except for libncurses++ and libncurses++w, which only ever install static libs) based on the setting of the "static-libs" USE flag.
Created attachment 236193 [details, diff] add USE=static-libs
looks sane enough. assuming it installs as expected, feel free to revbump with that. thanks ;).
Committed as 5.7-r4