A DESCRIPTION OF THE PROBLEM :
Upon compilation of the provided source code an incorrect warning is given for an unchecked conversion at the line containing the cast in the method named compiles_with_unchecked_cast_warning. It does not show this warning for the same operation in the method named compiles_with_no_warnings with the difference being that this method has a static context.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Compile the provided source code using javac version 1.8.0_191 .

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
No javac warnings should be given upon compilation.
ACTUAL -
Warning:java: unchecked cast
  required: InterfaceImpl
  found: Interface<java.lang.Object>

---------- BEGIN SOURCE ----------
class Scratch
{
    interface Interface<T>{}
    class InterfaceImpl implements Interface<Object>{}
    static class StaticInterfaceImpl implements Interface<Object>{}

    public void compiles_with_unchecked_cast_warning( Interface<Object> list )
    {
        InterfaceImpl classA = (InterfaceImpl)list;
    }

    public static void compiles_with_no_warnings( Interface<Object> list )
    {
        StaticInterfaceImpl classA = (StaticInterfaceImpl)list;
    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
The warnings can be suppressed by adding an annotation, @SuppressWarnings("unchecked"), above the statement.

FREQUENCY : always