[clang] [clang-tools-extra] [clang] Do not cache variable linkage before type deduction (PR #221474)

[Chen Miao via cfe-commits]

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@@ -0,0 +1,4 @@
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify %s
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ChenMiaoi wrote:

Could we add this case to an existing test file instead? It seems small enough that a separate file may not be necessary.

https://github.com/llvm/llvm-project/pull/221474