[clang] [analyzer] Variant checker bindings (PR #87886)

[Donát Nagy via cfe-commits]

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@@ -51,27 +47,29 @@ removeInformationStoredForDeadInstances(const CallEvent &Call,
 }
 
 template <class TypeMap>
-void handleConstructorAndAssignment(const CallEvent &Call, CheckerContext &C,
+bool handleConstructorAndAssignment(const CallEvent &Call, CheckerContext &C,
                                     SVal ThisSVal) {
   ProgramStateRef State = Call.getState();
 
   if (!State)
-    return;
+    return false;
 
   auto ArgSVal = Call.getArgSVal(0);
   const auto *ThisRegion = ThisSVal.getAsRegion();
   const auto *ArgMemRegion = ArgSVal.getAsRegion();
+  if (!ArgMemRegion)
+    return false;
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NagyDonat wrote:

Are you sure that `ThisRegion` cannot be null?

I suspect that `ThisSVal` might be `UnknownVal` in some circumstances (e.g. invalidation, complexity limit reached etc.) and that would lead to a `getAsRegion()` returning `nullptr` while modeling e.g. an assignment operator call.

https://github.com/llvm/llvm-project/pull/87886