[clang] [clang] LazyOffsetPtr: Use native pointer width (PR #111995)

[Chuanqi Xu via cfe-commits]

ChuanqiXu9 wrote:

> > > Can we remove `getAddressOfPointer` instead?. Where is it being used?
> > 
> > 
> > It is used in `VarDecl::getInitAddress()` in Decl.cpp. It looks like it is used indirectly by the StmtIterator
> 
> And that in turn is used in `StmtIterator`, and indeed we can end up _storing through_ the type-punned `Stmt*` here:
> 
> https://github.com/llvm/llvm-project/blob/9930a5a3338ba642c52292107e0f729328d79034/clang/lib/Frontend/Rewrite/RewriteObjC.cpp#L4561
> 
> (and also in `RewriteModernObjC.cpp`). Are the ObjC rewriters still in use? Can we remove them? If not it looks like we'll need to do some substantial rewrites.

@rjmccall @jansvoboda11 for ObjC topics.

https://github.com/llvm/llvm-project/pull/111995