> So what's wrong with that mangleof always return the correct mangle for symbol?

What exactly is *correct* mangle of symbol?  Maybe I'm an idiot here so please answer these three idiot questions.

1) Does the D define mangling as part of the ABI anywhere in it's language spec?
2) Does C++ define mangling as part of the ABI anywhere in it's language spec?
3) Does C define mangling as part of the ABI anywhere in it's *language* spec?