[clang] [Clang][Sema] Properly get captured 'this' pointer in lambdas with an explicit object parameter in constant evaluator (PR #81102)

[Aaron Ballman via cfe-commits]

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@@ -9037,45 +9055,46 @@ class PointerExprEvaluator
     return Error(E);
   }
   bool VisitCXXThisExpr(const CXXThisExpr *E) {
-    // Can't look at 'this' when checking a potential constant expression.
-    if (Info.checkingPotentialConstantExpression())
-      return false;
-    if (!Info.CurrentCall->This) {
+    auto DiagnoseInvalidUseOfThis = [&] {
       if (Info.getLangOpts().CPlusPlus11)
         Info.FFDiag(E, diag::note_constexpr_this) << E->isImplicit();
       else
         Info.FFDiag(E);
+    };
+
+    // Can't look at 'this' when checking a potential constant expression.
+    if (Info.checkingPotentialConstantExpression())
       return false;
+
+    const bool IsExplicitLambda =
----------------
AaronBallman wrote:

```suggestion
    bool IsExplicitLambda =
```

https://github.com/llvm/llvm-project/pull/81102