It might be more beneficial to try to get them to improve llvm support for their respective os+archs. It'd be less diversity of compilers but is probably a better investment for them than shoe-horning a poor/incomplete C++11 implementation into their aging compilers.
Yeah I'm pushing this route as well, but unfortunately the "hard to reproduce" part is all of the chip specific optimization. You could imagine that if their optimization phase(s) look nothing like llvm it would be really hard to get them to buy into that. I've had more success getting vendors to contribute gdb support (IBM has). I'll keep trying, though.
