[llvm] [llvm] Support building with c++23 (PR #154372)

[Shafik Yaghmour via llvm-commits]

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@@ -36,7 +36,7 @@ class MachineFunctionAnalysis
     std::unique_ptr<MachineFunction> MF;
 
   public:
-    Result(std::unique_ptr<MachineFunction> MF) : MF(std::move(MF)) {}
+    Result(std::unique_ptr<MachineFunction> MF);
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shafik wrote:

I am not necessarily arguing against this but I suspect if we do look into this, it won't be a quick fix and we will likely run into a lot of core issues along the way. I don't see this being resolved quickly. 

One also has to consider, we eventually need someone to implement reflection and that is likely going to be a large set of refactoring and a core issue generator galore. Likely the refactoring and core issues will kind of all be around the same areas. So we may be pretty resource constrained once this work starts. 

BTW Aaron is out for the next month.

https://github.com/llvm/llvm-project/pull/154372