It doesn't look like libreoffice actually needs gdk-pixbuf[X] dependency (but probably needs just gdk-pixbuf dep). Please check if it is really needed and remove the USE depend if it isn't. gdk-pixbuf USE=X just builds and installs an extra legacy library that isn't really used in modern applications. It doesn't mean gdk-pixbuf X support inside the main library, but a Xlib extra helper library that even gtk+ itself doesn't use at all.
The extra library is named libgdk_pixbuf_xlib-2.0.so - if libreoffice doesn't DT_NEEDED or dlopen it, it should be safe to remove the [X] part in the depend if configure doesn't specifically check for it either.
I can't find any NEEDED entry, and dont see it loaded when lowriter is running. So, I'm going to remove it from the live ebuilds and it'll drop out from the releases over the next version bumps. Please tell me if there is hurry.
commit 863d598a9ffc1f2e7ac6c73102d84766f1cd355e Author: Andreas K. Hüttel <dilfridge@gentoo.org> Date: Thu May 5 00:21:16 2016 +0200 app-office/libreoffice: Remove use-flag requirement on gdk-pixbuf, bug 582090 Package-Manager: portage-2.2.28 app-office/libreoffice/libreoffice-5.0.9999.ebuild | 2 +- app-office/libreoffice/libreoffice-5.1.9999.ebuild | 2 +- app-office/libreoffice/libreoffice-9999.ebuild | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-)
Fixed from 5.1.3 on