[clang] [Clang] Clarify diagnostic notes for implicitly generated deduction guides (PR #96084)

[Younan Zhang via cfe-commits]

================
@@ -12114,6 +12115,35 @@ static void NoteFunctionCandidate(Sema &S, OverloadCandidate *Cand,
     return;
   }
 
+  // If this is an implicit deduction guide against an implicitly defined
+  // constructor, add a note for it. Neither these deduction guides nor their
+  // corresponding constructors are explicitly spelled in the source code,
----------------
zyn0217 wrote:

But I'm not opposed to removing the filter and emitting all the candidates like what GCC does, anyway.

https://github.com/llvm/llvm-project/pull/96084