[clang] [C23] Implement N3018: The constexpr specifier for object definitions (PR #73099)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,6 @@
+// RUN: %clang_cc1 -fsyntax-only -verify=c23 -std=c23 %s -Wpre-c2x-compat
+// RUN: %clang_cc1 -fsyntax-only -verify=c17 -std=c17 %s
+
+
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AaronBallman wrote:

```suggestion

```

https://github.com/llvm/llvm-project/pull/73099