Clang with C++11 on RedHat 6.3

We are attempting to get clang configured with C++11 on RedHat 6.3 which
has GCC 4.4.6. Since the version of GCC does not support C++11 we have
tried using version 3.3 of clang to build clang 3.4 with the C++11
support and it fails to compile early with typedef's unknown. We have
also tried building the debugger which also fails to build usign GCC.

Any help on how to get to a build supportting C++11 would be
appreciated. Pretty painful if we must build the latest GCC to get clang

Can't you use Red Hat Developer Toolset?

There is a buildbot that has this version of gcc installed. It uses
Clang as the compiler, though. But it was bootstrapped using that