Gentoo's Bugzilla –
Attachment 539344 Details for
Bug 661046sci-mathematics/octave-4.4.0[graphicsmagick,imagemagick] with media-gfx/graphicsmagick-1.3.30[imagemagick]: libinterp/corefcn/__magick_read__.cc:801:11: error: ‘MAGICKCORE_QUANTUM_DEPTH’ was not declared in this scope