[clang] [clang][Sema] Fix assertion in `tryDiagnoseOverloadedCast` (PR #108021)

[Shafik Yaghmour via cfe-commits]

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@@ -446,7 +446,12 @@ static bool tryDiagnoseOverloadedCast(Sema &S, CastType CT,
     : InitializationKind::CreateCast(/*type range?*/ range);
   InitializationSequence sequence(S, entity, initKind, src);
 
-  assert(sequence.Failed() && "initialization succeeded on second try?");
+  // It could happen that a constructor failed to be used because
+  // it requires a temporary of a broken type. Still, it will be found when
+  // looking for a match.
+  if (!sequence.Failed())
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shafik wrote:

Does this mean that `destType->containsErrors()` is true? Perhaps both should be true otherwise assert?

https://github.com/llvm/llvm-project/pull/108021