[clang] Fix/interp init list unnamed bitfields (PR #87799)

[Timm Baeder via cfe-commits]

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@@ -0,0 +1,114 @@
+// UNSUPPORTED: asserts
+// REQUIRES: asserts
+// ^ this attempts to say "don't actually run this test", because it's broken
+//
+// The point of this test is to demonstrate something that ExprConstant accepts,
+// but Interp rejects. I had hoped to express that as the same file with two
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tbaederr wrote:

Please stop calling it "Interp", it just sounds silly.

https://github.com/llvm/llvm-project/pull/87799