[clang] [Clang][Sema] Reject undeduced static data members without initializers (#173349) (PR #174281)

[Yanzuo Liu via cfe-commits]

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@@ -1,5 +1,7 @@
 // RUN: %clang_cc1 -verify -std=c++14 -fcxx-exceptions %s
+// RUN: %clang_cc1 -fsyntax-only -verify -std=c++20 %s
 
+#if __cplusplus < 202002L
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zwuis wrote:

Can we remove this `#if`?

https://github.com/llvm/llvm-project/pull/174281