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

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@@ -0,0 +1,13 @@
+// RUN: %clang_cc1 -verify -fsyntax-only -std=c++2b -Wshadow-all %s
+
+namespace GH95707 {
+struct Foo {
+  int a; // expected-note {{previous declaration is here}}
+
+  void f1(this auto &self, int a) { self.a = a; }
+  void f2(int a) { } // expected-warning {{declaration shadows a field of 'GH95707::Foo'}}
+  void f3() {
+    (void)[&](this auto &self, int a) { };
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Sirraide wrote:

Ok, the test is correct now, but here we have a problem: The `a` parameter shadows the struct member, but it isn’t diagnosed—to be fair, we don’t currently diagnose that either, but it would be nice to do so. 

I think we do have to check if the `CXXMethodDecl` is a lambda call operator.

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