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

[Balazs Benics via cfe-commits]

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@@ -3068,11 +3111,174 @@ void MallocChecker::checkDeadSymbols(SymbolReaper &SymReaper,
   C.addTransition(state->set<RegionState>(RS), N);
 }
 
+// Use isWithinStdNamespace from CheckerHelpers.h instead of custom
+// implementation
+
+// Allowlist of owning smart pointers we want to recognize.
+// Start with unique_ptr and shared_ptr. (intentionally exclude weak_ptr)
+static bool isSmartOwningPtrType(QualType QT) {
+  QT = QT->getCanonicalTypeUnqualified();
+
+  // First try TemplateSpecializationType (for std smart pointers)
+  const auto *TST = QT->getAs<TemplateSpecializationType>();
+  if (TST) {
----------------
steakhal wrote:

```suggestion
  if (const auto *TST = QT->getAs<TemplateSpecializationType>()) {
```

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