[clang] [analyzer] Assert isImplicitObjectMemberFunction in SValBuilder::getCXXThis (PR #220114)

[Balázs Benics via cfe-commits]

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@@ -44,6 +44,9 @@ void CXXSelfAssignmentChecker::checkBeginFunction(CheckerContext &C) const {
     return;
   if (!MD->isCopyAssignmentOperator() && !MD->isMoveAssignmentOperator())
     return;
+  if (!MD->isImplicitObjectMemberFunction())
+    return;
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steakhal wrote:

This doesn't seem to be the right fix for this checker.
My impression would be that `CXXSelfAssignmentChecker` is outght to work regardless if the assignment has explicit or implicit obj param.

This also raises an important usability point: the checker devs who just want to model a binary operator (like assignment here), they want two svals: LHS and RHS.
What convenient ways can we offer to get them these that works regardless if the method has explicit or implicit obj param?

https://github.com/llvm/llvm-project/pull/220114