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import java.util.*;
import java.lang.*;
import java.io.*;
 
class Ideone
{
	public static List<? extends Object> produce(){
		return null; // Whatever
	}
 
	public static void main (String[] args) throws java.lang.Exception
	{
	}
 
	public static void a(NoGeneric noGeneric){
		noGeneric.call(produce());
	}
 
	public static <T> void b(Generic<T> generic){
		generic.call(produce());
	}
 
	public static <T, U extends Generic<T>> void d(U generic){
		generic.call(produce());
	}
 
	public static <T extends Generic> void c(T raw){
		raw.call(produce());
	}
}
 
class NoGeneric{
	public void call(List<Object> objects){	}
}
 
class Generic<T> {
	public void call(List<Object> objects){}
}

Main.java:16: error: incompatible types: List<CAP#1> cannot be converted to List<Object>
		noGeneric.call(produce());
		                      ^
  where CAP#1 is a fresh type-variable:
    CAP#1 extends Object from capture of ? extends Object
Main.java:20: error: incompatible types: List<CAP#1> cannot be converted to List<Object>
		generic.call(produce());
		                    ^
  where CAP#1 is a fresh type-variable:
    CAP#1 extends Object from capture of ? extends Object
Main.java:24: error: incompatible types: List<CAP#1> cannot be converted to List<Object>
		generic.call(produce());
		                    ^
  where CAP#1 is a fresh type-variable:
    CAP#1 extends Object from capture of ? extends Object
Note: Main.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
Note: Some messages have been simplified; recompile with -Xdiags:verbose to get full output
3 errors

Standard output is empty