[patch] Emit aliases for more constructors (V2)

[Rafael Espíndola]

> I haven't looked in detail at your change, but PR14610 (perhaps poorly
> explained by me in the bug) is more than about the duplicate debug info, but
> about the fact that we implement C1/C2 and D1/D2 by having one call the
> other so when you break on the ctor or dtor you actually break twice (once
> inside *1, then in *2 or whichever way it goes).
>
> By using aliases we get closer to (or the same as, in this instance) GCC's
> behavior where there's only one call on the stack rather than one ctor
> calling another ctor.
>
> I think it'd be fine to just remove the XFAIL (& update the bug to mention
> this). Might be worth mentioning that, if there are conditions where C1/C2
> can't be aliases, this bug will likely manifest there.

I agree that this is what is happening. My change doesn't fix that PR,
it just avoids the bug in the case the destructors can be aliased.

Any thoughts on the patch itself?

Cheers,
Rafael