[clang] [Clang] prevent assertion failure by avoiding casts on type declarations that require complete types (PR #101426)

[Shafik Yaghmour via cfe-commits]

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@@ -9267,14 +9267,14 @@ bool Sema::RequireLiteralType(SourceLocation Loc, QualType T,
   if (!RT)
     return true;
 
-  const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
-
   // A partially-defined class type can't be a literal type, because a literal
   // class type must have a trivial destructor (which can't be checked until
   // the class definition is complete).
   if (RequireCompleteType(Loc, ElemType, diag::note_non_literal_incomplete, T))
     return true;
 
+  const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
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shafik wrote:

I am surprised we have not run into this before this code was added in 2012.

https://github.com/llvm/llvm-project/pull/101426