[PATCH] D52674: [AST] Add Obj-C discriminator to MS ABI RTTI

[Shoaib Meenai via Phabricator via cfe-commits]

smeenai planned changes to this revision.
smeenai added a comment.

In https://reviews.llvm.org/D52674#1251931, @rjmccall wrote:

> In https://reviews.llvm.org/D52674#1251439, @smeenai wrote:
>
> > In https://reviews.llvm.org/D52674#1251419, @rjmccall wrote:
> >
> > > Conceptually this seems fine, but I think it would be good to stop and make sure we're using a consistent style when mangling extensions.  Currently it feels like every patch to add a Clang extension to the Microsoft mangling ends up inventing its own rules and crossing its fingers.
> >
> >
> > That's a fair concern.
> >
> > I believe most of the Obj-C extensions have been handled by @compnerd, and he's been following a pretty consistent scheme using the `__Objc` namespace, e.g. `void f(id<P>) {}` is mangled as `void __cdecl f(struct objc_object<struct __ObjC::Protocol<struct P> > *)`. I could certainly try to implement something similar here, except as I mentioned, I'm pretty sure it would require maintaining some state in the demangler for indicating whether we were mangling for RTTI.
>
>
> State wouldn't really be the right solution anyway, although it might work because of the structural restrictions on Objective-C types.  If you wanted to keep that same rule, I think you could probably just pass a (default=`false`) flag down to the `ObjCObjectPointerType`, `ObjCObjectType`, and `ObjCInterfaceType` cases.  (The pointee type of the former will always be one of the latter two.)


Ah, there are fewer hops between the `mangleType` call and its ultimate destination than I was expecting, so a default parameter would work. I'll change this accordingly, thanks.


Repository:
  rC Clang

https://reviews.llvm.org/D52674