FULL PRODUCT VERSION :
C:\Program Files\Java\jdk1.8.0_101\bin>java -version
java version "1.8.0_101"
Java(TM) SE Runtime Environment (build 1.8.0_101-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.101-b13, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Windows 7 64bit Ultimate Edition

A DESCRIPTION OF THE PROBLEM :
class Fruit implements Comparable<Fruit>
{
    @Override
    public int compareTo(Fruit o) { return 0; }
}

// Compiler not giving error upon wrong type passing in generic function

class Apple extends Fruit{}

class Main
{

    public static void main (String args[])
    {
        function(new Apple()); // this shouldn't work because Apple is implementing Comparable<Fruit>, not Comparable<Apple>
    }

    public static<T extends Comparable<T>> void function(T t){}
}

REGRESSION. Last worked in version 6u45

ADDITIONAL REGRESSION INFORMATION:
java version "1.6.0_45"
Java(TM) SE Runtime Environment (build 1.6.0_45-b06)
Java HotSpot(TM) 64-Bit Server VM (build 20.45-b01, mixed mode)

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Step 1 - Create Class Fruit

class Fruit implements Comparable<Fruit>
{
    @Override
    public int compareTo(Fruit o) { return 0; }
}

Step 2 - Create Class Apple

class Apple extends Fruit
{
}

Step 3 - Create Class Main

class Main
{

    public static void main (String args[])
    {
        function(new Apple()); // this shouldn't work because Apple is implementing Comparable<Fruit>, not Comparable<Apple>
    }

    public static<T extends Comparable<T>> void function(T t){}
}

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
<T extends Comparable<T>> working like <T extends Comparable<? super T>>

We were expecting compilation error caused by generics

like compiler gives error upon changing function defination to
        public static<T extends Comparable<T>> void function(List<T> t){}

and upon calling
        function(new ArrayList<Apple>());


ACTUAL -
Compiles without any issue.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.util.ArrayList;
import java.util.List;

public class SuperT {

public static void main (String args[]){

function(new ArrayList<Apple>()); // generic compilation error
function(new Apple()); // compiles without issue , although it should give error
}

private static<T extends Comparable<T>> void function(T t){

}

private static<T extends Comparable<T>> void function(List<T> t){ }
}

class Fruit implements Comparable<Fruit>
{
@Override
public int compareTo(Fruit o) { return 0; }
}

class Apple extends Fruit{}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Not yet.