Building R-3.1.1 on a PPC requires using a compiler that can properly handle ObjectiveC code

[josephsacco]

R-3.1.1, with default variants, builds on a PPC provided: (1) the Apple compiler is used for compiling ObjectiveC code, and (2) the gcc48 suite of compilers is used for everything else:

sudo port install R configure.compiler=macports-gcc-4.8 configure.objc=/usr/bin/gcc-4.2

The Apple compiler is necessary to properly compile the one .m file

./src/library/grDevices/src/qdCocoa.m

If gcc-mp-4.8 is used instead, the quartz graphic device will fail to launch, causing R to exit because of an error.

-Joseph