[clang] [Clang] eliminate shadowing warnings for parameters using deducing this (PR #114813)

[via cfe-commits]

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@@ -8236,11 +8236,14 @@ void Sema::CheckShadow(NamedDecl *D, NamedDecl *ShadowedDecl,
   DeclContext *NewDC = D->getDeclContext();
 
   if (FieldDecl *FD = dyn_cast<FieldDecl>(ShadowedDecl)) {
-    // Fields are not shadowed by variables in C++ static methods.
-    if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC))
+    if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC)) {
+      // Fields are not shadowed by variables in C++ static methods.
       if (MD->isStatic())
         return;
 
+      if (!MD->getParent()->isLambda() && MD->isExplicitObjectMemberFunction())
+        return;
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Sirraide wrote:

It makes sense that that would fail, but I’m still a bit confused as to how we end up w/ a `CXXMethodDecl` whose type (after desugaring) isn’t a `FunctionProtoType`. If that *does* happen somehow, I should hope that `isInvalidDecl()` also returns `true`, in which case you’d check for that first.

https://github.com/llvm/llvm-project/pull/114813