/var/tmp/portage/dev-games/openscenegraph-2.8.3/work/OpenSceneGraph-2.8.3/src/osgPlugins/curl/ReaderWriterCURL.cpp:24:24: fatal error: curl/types.h: No such file or directory compilation terminated. make[2]: *** [src/osgPlugins/curl/CMakeFiles/osgdb_curl.dir/ReaderWriterCURL.o] Error 1
Accoding to bug #376007 it should be safe to simply stop including that file.
Created attachment 287625 [details, diff] osg-curl.patch Patch as above.
in portage. thanks for the bug report and patch.