[clang] [clang][Sema] Improve template argument deduction diagnostic (PR #122754)

[Aidan Goldfarb via cfe-commits]

================
@@ -11714,13 +11714,37 @@ static void DiagnoseBadDeduction(Sema &S, NamedDecl *Found, Decl *Templated,
     return;
   }
 
-  case TemplateDeductionResult::InvalidExplicitArguments:
+  case TemplateDeductionResult::InvalidExplicitArguments: {
     assert(ParamD && "no parameter found for invalid explicit arguments");
-    if (ParamD->getDeclName())
-      S.Diag(Templated->getLocation(),
-             diag::note_ovl_candidate_explicit_arg_mismatch_named)
-          << ParamD->getDeclName();
-    else {
+    if (ParamD->getDeclName()) {
----------------
AidanGoldfarb wrote:

My most recent change split up the information into two diags, much like GCC and what I think you were suggesting. Please let me know if this was what you had in mind

https://github.com/llvm/llvm-project/pull/122754