[petsc-dev] defaulting gnu compilers on Apple

[Sean Farley]

balay at mcs.anl.gov writes:

> unless everyone is using xcode5 - I think gcc/g++ is a safer default.

Apple stopped shipping gcc with Xcode 4.2 [1]. Since that version,
everyone has been using the llvm backend. Only in version >= 5.0 has
llvm-gcc been dropped. And in Mavericks only libc++ (and not libstdc++)
is shipped.

[1] http://en.wikipedia.org/wiki/Xcode#Toolchain_Versions