[libcxx-commits] [PATCH] D102135: [libcxx][ranges] adds _`copyable-box`_

[Tim Song via Phabricator via libcxx-commits]

tcanens added inline comments.


================
Comment at: libcxx/include/__ranges/copyable_box.h:111
+  class __copyable_box<_Tp> {
+    [[no_unique_address]] _Tp __val_;
+
----------------
zoecarver wrote:
> What do you think about this problem: https://reviews.llvm.org/D103056#inline-999709
> 
> Basically, if we have two copyable-box members that are both `no_unique_address` where T is copyable and empty, we will never invoke the copy constructor on assignment. I think this is probably a bug with copyable box, and not its users. 
`no_unique_address` doesn't change the basic object model rule that two living objects of the same type must have distinct addresses.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D102135/new/

https://reviews.llvm.org/D102135