[libcxx-commits] [PATCH] D154499: [libc++] Do not use stringbuf's string after move

[Louis Dionne via Phabricator via libcxx-commits]

ldionne commandeered this revision.
ldionne added a reviewer: pfusik.
ldionne added a comment.

Commandeering to finish for the GH PR transition.

After consideration, I think our current tests are lacking a bit but there is no risk of use-after-move. Indeed, when we set `__p = const_cast<char_type*>(__rhs.__str_.data());`, `__p` is:

- `nullptr` if the string was not using SSO, because it was moved-out-from above in `__str_ = _VSTD::move(__rhs.__str_);`
- a pointer to the start of the SSO inside `__rhs.__str_` if the string was using SSO

Either way, we are not reusing the storage incorrectly. I will commandeer and fix the tests, but I think our current implementation is fine.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D154499/new/

https://reviews.llvm.org/D154499