[clang] [clang][dataflow] Fix crash on base-to-derived cast of unmodeled pointer value. (PR #179060)

[Yitzhak Mandelbaum via cfe-commits]

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@@ -328,9 +328,9 @@ class TransferVisitor : public ConstStmtVisitor<TransferVisitor> {
       RecordStorageLocation *Loc = nullptr;
       if (S->getType()->isPointerType()) {
         auto *PV = Env.get<PointerValue>(*SubExpr);
-        assert(PV != nullptr);
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ymand wrote:

Why remove? My sense is that the intuition is that this situation shouldn't happen, but if it does we don't want to crash in release code, so we handle the case. But, we still want to find it in debug. If you think its correct to remove, please explain (that is, I understand it could be a mistake/left over, but would like that verified).

https://github.com/llvm/llvm-project/pull/179060