swift234

When trying out potential bindings for a given type variable, take greater measures not to try the same binding against a bound generic type more than once. Multiple attempts at bindings can result in massive slow downs in overload resolution, because we'll potentially post many duplicate results to the solution. (In cases such as "[0..<10, 0..<10, 0..<10, 0..<10, 0..<10]", for example.)