If qgis-2.18.3 is emerged with USE=-webkit, but dev-qt/qtwebkit:4 is installed on the system nevertheless, the USE flag is ignored and /usr/bin/qbrowser and /usr/lib/libqgis_app.so link against libQtWebKit.so. This looks like a bug in the qgis build system; unfortunately I lack sufficient knowledge about cmake to fix it myself.
It should be fixed in commit: https://gitweb.gentoo.org/repo/gentoo.git/commit/sci-geosciences/qgis/qgis-2.18.3.ebuild?id=0333e35edc0fe153dcf8227974ee05cec0844ce8 Are you sure you synced your tree since 21 of January?
(In reply to Amy Liffey from comment #1) > Are you sure you synced your tree since 21 of January? Yes, I am. I'm using the current tree; the qgis ebuilds before Jan 21 wouldn't have had the webkit USE flag, anyway.
(In reply to Luis Ressel from comment #2) > (In reply to Amy Liffey from comment #1) > > Are you sure you synced your tree since 21 of January? > > Yes, I am. I'm using the current tree; the qgis ebuilds before Jan 21 > wouldn't have had the webkit USE flag, anyway. Oh yes I read it badly my bad sorry.
Thanks, fixed with qgis-2.18.3-r1.