[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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@@ -8485,6 +8485,53 @@ class LValueExprEvaluator
 };
 } // end anonymous namespace
 
+/// Get an lvalue to a field of a lambda's closure type.
+static bool HandleLambdaCapture(EvalInfo &Info, const Expr *E, LValue &Result,
+                                const CXXMethodDecl *MD, const FieldDecl *FD,
+                                bool LValueToRValueConversion) {
+  // Static lambda function call operators can't have captures. We already
+  // diagnosed this, so bail out here.
+  if (MD->isStatic()) {
+    assert(Info.CurrentCall->This == nullptr &&
+           "This should not be set for a static call operator");
+    return false;
+  }
+
+  // Start with 'Result' referring to the complete closure object...
+  if (MD->isExplicitObjectMemberFunction()) {
+    // Self may be passed by reference or by value.
+    auto *Self = MD->getParamDecl(0);
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AaronBallman wrote:

Should spell this type out as well

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