[clang] [analyzer] Fix StackAddrEscapeChecker crash on temporary object fields (PR #66493)

[via cfe-commits]

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@@ -398,7 +400,7 @@ void StackAddrEscapeChecker::checkEndFunction(const ReturnStmt *RS,
     }(Referrer->getMemorySpace());
 
     // This cast supposed to succeed.
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DonatNagyE wrote:

Perhaps explain why will the cast succeed (or, alternatively, just remove this meaningless comment).

https://github.com/llvm/llvm-project/pull/66493