[llvm] [ADT] Deprecate ArrayRef(std::nullopt) (PR #146011)

[Kazu Hirata via llvm-commits]

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@@ -67,7 +67,7 @@ namespace llvm {
     /*implicit*/ ArrayRef() = default;
 
     /// Construct an empty ArrayRef from std::nullopt.
-    /*implicit*/ ArrayRef(std::nullopt_t) {}
+    /*implicit*/ [[deprecated]] ArrayRef(std::nullopt_t) {}
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kazutakahirata wrote:

Addressed in the latest revision.  Thanks!

https://github.com/llvm/llvm-project/pull/146011