[clang] [analyzer] Improve dangling value tracking in DanglingPtrDeref (PR #211818)

[via cfe-commits]

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@@ -15,6 +15,10 @@ getDanglingRegionsAfterReturn(SVal Source, ProgramStateRef State,
 
 /// Returns true if the underlying MemRegion is deallocated.
 bool isDeallocated(ProgramStateRef State, const MemRegion *Region);
+
+/// Returns the descriptive name of the memory region or a placeholder if a
+/// descriptive name cannot be constructed for it.
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isuckatcs wrote:

> or a placeholder if a descriptive name cannot be constructed for it.

Where do we construct this placeholder? Is it something handled by `MemRegion::getDescriptiveName()`?

https://github.com/llvm/llvm-project/pull/211818