[clang] [Clang] support storage-class specifiers in C23 compound literals (PR #212559)

[Nick Desaulniers via cfe-commits]

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@@ -185,7 +185,7 @@ constexpr struct S5 V47[3] = {randomFoo() };
 // expected-error at -1 {{constexpr variable 'V47' must be initialized by a constant expression}}
 
 const static int V48 = V38;
-constexpr static int V49 = V48;
+constexpr static int V49 = V48; // expected-warning {{expression is not an integer constant expression}}
 // expected-error at -1 {{constexpr variable 'V49' must be initialized by a constant expression}}
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nickdesaulniers wrote:

duplicative?

https://github.com/llvm/llvm-project/pull/212559