The error in question being:
make: *** No rule to make target `gdl-3-docs.sgml', needed by `html-build.stamp'. Stop.
Probably an upstream issue.
a build.log and emerge --info are still required for overlay reports.
<ass-mode> USE=doc emerge -1 =gdl-2.91.4 Tell me you fail to reproduce (what you'll probably do anyway) and I will provide what you request</ass-mode>
OK, I'll attach when I get home.
Sorry I don't run the overlay, but there is no way to check if the problem is something else than you think it is without the requested information. It is the minimal information requested as stated by portage and bugzilla.
And please keep your ass-mode to yourself or I'll have to call in userrel, thanks.