x11-drivers/xf86-video-nouveau fails compilation if x11-proto/dri2proto is not installed. There must be a build-time dependency on dri2proto. Reproducible: Always
Can you please attach the build.log and the environment file on the failed emerge process? Thanks
Created attachment 241863 [details] bu'ld log
Created attachment 241865 [details] environment file
I should add that I mostly use binary packages on this machine. The lack of the dependency may have slipped because use of binary packages in gentoo is not widespread.
Fixed in CVS.