[clang] [Clang] Static and explicit object member functions with the same parameter-type-lists (PR #93430)

[Aaron Ballman via cfe-commits]

================
@@ -5813,6 +5813,27 @@ static TypoCorrection TryTypoCorrectionForCall(Sema &S, Expr *Fn,
   return TypoCorrection();
 }
 
+// [C++26][[expr.unary.op]/p4
+// A pointer to member is only formed when an explicit &
+// is used and its operand is a qualified-id not enclosed in parentheses.
+static bool isParenthetizedAndQualifiedAddressOfExpr(Expr *Fn) {
+  if (!isa<ParenExpr>(Fn))
+    return false;
+
+  Fn = Fn->IgnoreParens();
+
+  auto *UO = dyn_cast<UnaryOperator>(Fn);
+  if (!UO || UO->getOpcode() != clang::UO_AddrOf)
+    return false;
+  if (auto *DRE = dyn_cast<DeclRefExpr>(UO->getSubExpr()->IgnoreParens())) {
+    return DRE->hasQualifier();
+  }
+  if (auto *OVL = dyn_cast<OverloadExpr>(UO->getSubExpr()->IgnoreParens())) {
+    return OVL->getQualifier();
+  }
----------------
AaronBallman wrote:

```suggestion
  if (auto *DRE = dyn_cast<DeclRefExpr>(UO->getSubExpr()->IgnoreParens()))
    return DRE->hasQualifier();
  if (auto *OVL = dyn_cast<OverloadExpr>(UO->getSubExpr()->IgnoreParens()))
    return OVL->getQualifier();
```
additional: is it possible to get a `MemberExpr` instead of a `DeclRefExpr`? (Thinking about accessing a data member by name; looks like a `DeclRefExpr` but is actually a `MemberExpr`.)

https://github.com/llvm/llvm-project/pull/93430