[libcxx-commits] [PATCH] D106763: [libc++][RFC] Disable incomplete library features.

[Mark de Wever via Phabricator via libcxx-commits]

Mordante marked an inline comment as done.
Mordante added a comment.

In D106763#2908310 <https://reviews.llvm.org/D106763#2908310>, @Quuxplusone wrote:

>> Consider that `__has_include(<format>)` will now return the "wrong" value; it would be better and simpler if you could just figure out a way to stop the build system from installing that header in `include/c++/v1/` at all. However, this is not a new problem: e.g., `__has_include(<variant>)` already has the "wrong" value in C++03/11/14 mode; we definitely have no way to fix that.
>
> IMO `__has_include(<variant>)` is the wrong tool for the job. If a user wants to to test the status of the headers they can use `__has_include(<version>)` and when that's available test the appropriate feature-test macro.

@Quuxplusone It seem http://wg21.link/SD6 recommends this practice. D107134 <https://reviews.llvm.org/D107134> should allow this usage pattern.


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https://reviews.llvm.org/D106763