[libcxx-commits] [libcxx] [libc++] Reenable codecvt in the dylib. (PR #73679)

[Mark de Wever via libcxx-commits]

mordante wrote:

> I just fetched the toolchain from the failed task I mentioned. By default, without supplying any std flag, the `__cplusplus` macro value is `201402` .
> 
> I belive what @petrhosek found out about how libcxx select c++ std is the reason why we are seeing the test failures. And that is why upstream bots is not seeing this test error.

I'm quite puzzled, based on the `__cplusplus`  you're using C++14, but when forcing C++23 things are fixed. This issue should only occur in C++26. I wonder whether this could be a side effect of f97a579b74a6e65a3f58813b36f6a789102ce315?

> Thanks a lot for the analysis @petrhosek , this is extremely useful. So yeah the problem's on our side, basically the library fails to build in C++26 mode on Windows and we never noticed because our Windows bot is building as C++23.

The first part of the dylib we would have found if any bot tried to build the dylib with C++26. The latest issues would require a Windows bot to test C++26.

@zeroomega @petrhosek I just pushed another commit can you test whether that completely fixes the issue for you?



https://github.com/llvm/llvm-project/pull/73679