While testing a variety of different build configurations for gcc, I spotted that using `USE="-* go" emerge gcc, I get : >>> Running pre-merge checks for sys-devel/gcc-7.2.0-r1 * Go requires a C++ compiler, disabled due to USE="-cxx" Could this warning be made fatal ? I don't see the point of telling it in a warning and not building what the user wanted. Especially when doing a long emerge run when it is easy to miss some warnings. Reproducible: Always Actual Results: User with USE="-cxx go" gets a gcc without go but a simple warning. Expected Results: Emerge dies like when REQUIRED_USE constraints are unmet in other ebuilds. I set the severity as minor because I spotted it during tests, I don't expect much people wanting a go compiler without a c++ one.
Yeah, we can leverage REQUIRED_USE for that.
