[clang] [analyzer] MallocChecker – Fix false positive leak for smart pointers in temporary objects (PR #152751)

[Ivan Murashko via cfe-commits]

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@@ -1096,6 +1100,41 @@ class StopTrackingCallback final : public SymbolVisitor {
     return true;
   }
 };
+
+/// EscapeTrackedCallback - A SymbolVisitor that marks allocated symbols as
+/// escaped.
+///
+/// This visitor is used to suppress false positive leak reports when smart
+/// pointers are nested in temporary objects passed by value to functions. When
+/// the analyzer can't see the destructor calls for temporary objects, it may
+/// incorrectly report leaks for memory that will be properly freed by the smart
+/// pointer destructors.
+///
+/// The visitor traverses reachable symbols from a given set of memory regions
+/// (typically smart pointer field regions) and marks any allocated symbols as
+/// escaped. Escaped symbols are not reported as leaks by checkDeadSymbols.
+///
+/// Usage:
+///   auto Scan =
+///   State->scanReachableSymbols<EscapeTrackedCallback>(RootRegions);
+///   ProgramStateRef NewState = Scan.getState();
+///   if (NewState != State) C.addTransition(NewState);
+class EscapeTrackedCallback final : public SymbolVisitor {
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ivanmurashko wrote:

Updated as suggested: constructor is now private, added EscapeTrackedRegionsReachableFrom() static helper, and replaced direct visitor usage with the new helper.

https://github.com/llvm/llvm-project/pull/152751