[clang] [clang] Fix false positive with -Wdocumentation and explicit instanti… (PR #178223)

[Mariya Podchishchaeva via cfe-commits]

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@@ -1536,3 +1536,13 @@ template <class T, class = void> constexpr auto var = T{};
 template <typename T> constexpr auto var<T> = T{};
 } // namespace GH144775
 #endif
+
+namespace GH64087
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Fznamznon wrote:

I was curious about the original problem but can't see it using the test https://godbolt.org/z/YMaWfnMx9  .
The GH issue does have https://godbolt.org/z/cac86944Y but if I switch it to class, the warning disappears -https://godbolt.org/z/abx7oPcb8 . I wonder if the test should exercise template functions instead? 

https://github.com/llvm/llvm-project/pull/178223