[clang] [clang] Implement CWG2428 "Deprecating a concept" (PR #92295)

[via cfe-commits]

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@@ -8092,6 +8092,18 @@ void Sema::checkCall(NamedDecl *FDecl, const FunctionProtoType *Proto,
     diagnoseArgDependentDiagnoseIfAttrs(FD, ThisArg, Args, Loc);
 }
 
+void Sema::CheckConstrainedAuto(TypeSourceInfo *TS) {
+  if (getLangOpts().CPlusPlus20) {
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cor3ntin wrote:

Does the check for `getLangOpts().CPlusPlus20` does anything here?

https://github.com/llvm/llvm-project/pull/92295