[clang] [clang] Fix assertion failure in constexpr union deserialization (PR #140179)

[Alexander Kornienko via cfe-commits]

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@@ -414,7 +414,7 @@ let Class = PropertyTypeCase<APValue, "Union"> in {
     let Read = [{ node.getUnionValue() }];
   }
   def : Creator<[{
-    return APValue(cast<clang::FieldDecl>(fieldDecl), std::move(value));
+    return APValue(cast_if_present<clang::FieldDecl>(fieldDecl), std::move(value));
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alexfh wrote:

Sorry to make you reconstruct this explanation yourself @hokein. Added a comment.

https://github.com/llvm/llvm-project/pull/140179