// CS8178: `await' cannot be used in an expression containing a call to `X.Wrap(int)' because it returns by reference // Line: 12 using System.Threading.Tasks; class X { int x; async Task Test () { Foo (ref Wrap (await Task.FromResult (1))) = 4; } ref int Wrap (int arg) { return ref x; } static ref int Foo (ref int arg) { return ref arg; } }