[PATCH] D45470: Emit an error when include <atomic> after <stdatomic.h>

[JF Bastien via Phabricator via cfe-commits]

jfb added a comment.

In https://reviews.llvm.org/D45470#1092212, @vsapsai wrote:

> Here is another approach that should emit an error only when mixing headers
>  causes compilation problems.
>
> Have no ideas how to test the change. `-verify` doesn't work with fatal errors
>  and libcxx doesn't use FileCheck. Performed only manual testing.


This worked with `<atomic>` before `<stdatomic.h>` as well as with the order reversed?

LGTM pending testing answer. This seems simpler than implementing  http://wg21.link/p0943 outright, though that would still be the best solution IMO.



================
Comment at: libcxx/include/atomic:558
 #endif
+#ifdef kill_dependency
+#error C++ standard library is incompatible with <stdatomic.h>
----------------
I checked and C guarantees that this is a macro :)


https://reviews.llvm.org/D45470