[libcxx-commits] [PATCH] D101729: [libcxx] deprecates `std::iterator` and removes it as a base class

[Eric Fiselier via Phabricator via libcxx-commits]

EricWF added a comment.

Removing the `std::iterator` inheritance is potentially ABI breaking. In particular in the case of `reverse_iterator`.
If the iterator provided to `reverse_iterator` also inherits from `std::iterator`, then the first member of `reverse_iterator` goes from having an offset of 4 to an offset of 0 bytes
(because the compiler couldn't place the same empty base at the same address).

I'm not sure how much we care, but I see this being a case that could easily arise in real world code.
@ldionne thoughts?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D101729/new/

https://reviews.llvm.org/D101729