[libcxx-commits] [libcxx] [libc++][modules] Uses _LIBCPP_USING_IF_EXISTS. (PR #90409)

[Mark de Wever via libcxx-commits]

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@@ -10,132 +10,132 @@
 export namespace std {
 
   // [atomics.order], order and consistency
-  using std::memory_order;
-  using std::memory_order_acq_rel;
-  using std::memory_order_acquire;
-  using std::memory_order_consume;
-  using std::memory_order_relaxed;
-  using std::memory_order_release;
-  using std::memory_order_seq_cst;
+  using std::memory_order _LIBCPP_USING_IF_EXISTS;
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mordante wrote:

These values are from C headers too.
I indeed added what we did for the C-headers. Before I did not add all of these and that lead to several issues. So I agree with @ldionne's approach.

https://github.com/llvm/llvm-project/pull/90409