[clang] [clang][SemaCXX] Fix crash caused by unresolved overloaded function type when using `__builtin_bit_cast` (PR #200574)

[Corentin Jabot via cfe-commits]

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@@ -439,6 +439,13 @@ ExprResult Sema::ActOnBuiltinBitCastExpr(SourceLocation KWLoc, Declarator &D,
 ExprResult Sema::BuildBuiltinBitCastExpr(SourceLocation KWLoc,
                                          TypeSourceInfo *TSI, Expr *Operand,
                                          SourceLocation RParenLoc) {
+  if (Operand->hasPlaceholderType()) {
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cor3ntin wrote:

Maybe but we are not consistent about that - It's pre-existing here, Operand is used L454 without null check. But yeah, an assert would not hurt

https://github.com/llvm/llvm-project/pull/200574