[clang] Diagnose problematic uses of constructor/destructor attribute (PR #67673)

[Erich Keane via cfe-commits]

erichkeane wrote:

I missed the compiler-rt bit there, thats a real shame, this is a really valueable patch that I'd hope someone would take up.  While "GCC Doesnt Error" isn't particularly compelling and we SHOULD be better than that, I'd also prefer not throwing the baby out with the bath water.

That said, if you're unable to do the cmake work, I'm hopeful someone else can come along.  Is there a 'beginner commandeer' (ala-beginner-bug?) tag we could throw on this? 

https://github.com/llvm/llvm-project/pull/67673