Building matplotlib-1.2.1 with the doc USE flag enabled causes a sandbox violation on attempting to emerge. See attached logs. Reproducible: Always
Created attachment 358608 [details] output of emerge --info
Created attachment 358610 [details] Sandbox violation log
Created attachment 358612 [details] full build log
Is this still reproducible with latest matplotlib? No clue what is happening here.
I can confirm this works now with matplotlib-1.3.0 and the doc flag.