I didn't realize that clang is mostly a drop in replacement for cl, and matches the C++ abi. That in of itself is awesome.
clang-cl is a drop-in replacement for cl (even the command lines are the same).
But clang-cl is just a driver for clang, and it's still possible to get the ABI compatibility without clang-cl, but you have to know what you're doing and get the flags right.