[clang] [Clang] CWG2789 Overload resolution with implicit and explicit object… (PR #73493)

[Aaron Ballman via cfe-commits]

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@@ -10121,22 +10143,41 @@ static bool haveSameParameterTypes(ASTContext &Context, const FunctionDecl *F1,
 
 /// We're allowed to use constraints partial ordering only if the candidates
 /// have the same parameter types:
-/// [over.match.best]p2.6
-/// F1 and F2 are non-template functions with the same parameter-type-lists,
-/// and F1 is more constrained than F2 [...]
+/// [over.match.best.general]p2.6
+/// F1 and F2 are non-template functions with the same
+/// non-object-parameter-type-lists, and F1 is more constrained than F2 [...]
 static bool sameFunctionParameterTypeLists(Sema &S,
-                                          const OverloadCandidate &Cand1,
-                                          const OverloadCandidate &Cand2) {
-  if (Cand1.Function && Cand2.Function) {
-    auto *PT1 = cast<FunctionProtoType>(Cand1.Function->getFunctionType());
-    auto *PT2 = cast<FunctionProtoType>(Cand2.Function->getFunctionType());
-    if (PT1->getNumParams() == PT2->getNumParams() &&
-        PT1->isVariadic() == PT2->isVariadic() &&
-        S.FunctionParamTypesAreEqual(PT1, PT2, nullptr,
-                                     Cand1.isReversed() ^ Cand2.isReversed()))
-      return true;
+                                           const OverloadCandidate &Cand1,
+                                           const OverloadCandidate &Cand2) {
+  if (!Cand1.Function || !Cand2.Function)
+    return false;
+
+  auto *Fn1 = Cand1.Function;
+  auto *Fn2 = Cand2.Function;
----------------
AaronBallman wrote:

Please spell out the types explicitly as they're not spelled by the initializer.

https://github.com/llvm/llvm-project/pull/73493