[clang] [coroutines] Introduce [[clang::coro_return_type]] and [[clang::coro_wrapper]] (PR #71945)

[Ilya Biryukov via cfe-commits]

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@@ -11183,6 +11183,7 @@ class Sema final {
   bool buildCoroutineParameterMoves(SourceLocation Loc);
   VarDecl *buildCoroutinePromise(SourceLocation Loc);
   void CheckCompletedCoroutineBody(FunctionDecl *FD, Stmt *&Body);
+  void CheckCoroutineWrapper(FunctionDecl *FD);
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ilya-biryukov wrote:

NIT: could you document this check is a Clang extension and mention the attribute names?

https://github.com/llvm/llvm-project/pull/71945