[clang] [Clang] [C++26] Implement P2573R2: `= delete("should have a reason");` (PR #86526)

[via cfe-commits]

================
@@ -18157,7 +18158,7 @@ void Sema::SetDeclDeleted(Decl *Dcl, SourceLocation DelLoc) {
   // C++11 [dcl.fct.def.delete]p4:
   //  A deleted function is implicitly inline.
   Fn->setImplicitlyInline();
-  Fn->setDeletedAsWritten();
+  Fn->setDeletedWithMessage(Message);
----------------
Sirraide wrote:

> I think we should just add the Message as parameter to `setDeletedAsWritten`

I don’t think that would work too well after all now that the message is stored in the `DefaultFunctionInfo`, because `setDeletedAsWritten()` is called in many places, but the `DefaultFunctionInfo` needs to be constructed separately in some. Currently, there is only one place where `setDeletedAsWritten()` is called and then immediately after `setDeletedMessage()`, so I don’t thing it’s worth merging the two.


https://github.com/llvm/llvm-project/pull/86526