Gthumb doesn't compile with LDFLAGS="-Wl,--as-needed", because libgthumb.so is not linked to the numerous libs it uses, and thus has tens of unresolved symbols. The attached patch fixes that by setting libgthumb_la_LIBADD in its Makefile.
Created attachment 86296 [details, diff] files/gthumb-2.6.8-as-needed.patch
Created attachment 86297 [details, diff] gthumb-2.6.8-r2-ebuild.patch Patch for the ebuild.
thanks, in cvs, along with 2.6.9.