[libcxx-commits] [libcxx] [libc++][modules] Add using_if_exists attribute (#77559) (PR #78909)

[Mark de Wever via libcxx-commits]

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@@ -16,10 +16,10 @@ export {
   // [support.start.term], start and termination
   using ::_Exit;
   using ::abort;
-  using ::at_quick_exit;
+  using ::at_quick_exit _LIBCPP_USING_IF_EXISTS;
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mordante wrote:

@ldionne we indeed probably should, I really hope we can start to make progress adding more CI testing for modules. For now I prefer to keep it so this lands in LLVM 18.

https://github.com/llvm/llvm-project/pull/78909