This package installs also static libs ".a" please provide do add relative USE. TIA /usr/lib/libexiv2.a /usr/lib/libexiv2.so.6.0.0 /usr/lib/pkgconfig/exiv2.pc /usr/lib/libexiv2.la /usr/lib/libexiv2.so /usr/lib/libexiv2.so.6 Please remove also .la if is not needed.
fixed with media-gfx/exiv2-0.23.