Compiler Error CS0221

Constant value 'value' cannot be converted to a 'type' (use 'unchecked' syntax to override)

An assignment operation that would result in a data loss was detected by checked, which is on by default. Either correct the assignment or use unchecked to resolve this error. For more information, see Checked and Unchecked (C# Reference).

The following sample generates CS0221:

// CS0221.cs
public class MyClass
{
   public static void Main()
   {
      // unchecked
      // {
         int a = (int)0xFFFFFFFF;   // CS0221
         a++;
      // }
   }
}