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

[Nick Desaulniers via cfe-commits]

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@@ -423,7 +423,7 @@ bool issue155507(v2int16_t a, v2int16_t b) {
     return __builtin_bit_cast(unsigned char, __builtin_convertvector(a == b, __vbool2)) == 0b11;
 }
 
-constexpr bool b2 = (bool)nullptr;
+constexpr bool b2 = (bool)nullptr; // expected-warning {{expression is not an integer constant expression}}
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nickdesaulniers wrote:

uh...what's going on here? This looks valid to me. I don't think we should be warning here; this looks like a false positive.  https://github.com/llvm/llvm-project/pull/212559/changes/d656b81f0d018b3623cd28be0909a00de2747347 seems like a _regression_.

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