Solve libcxx issue in ConfigureEnvironment

[memsharded]

It is always None:

         try:
            self.compiler = str(self._settings.compiler)
        except:
            self.compiler = None


        try:
            self.libcxx = str(self.compiler.libcxx)
        except:
            self.libcxx = None

So I am getting some weird link errors in Protobuf