GenericRelation's on proxy models do not cascade deletion

[Mehmet Dogan]

For this code (from ​this StackOverflow question ):

class Person(models.Model):
    identity = models.CharField(max_length=13, verbose_name="ID")
    name = models.CharField(max_length=255, verbose_name="Name")
    board = GenericRelation('second_app.BoardMember') #Second Try

    def __unicode__(self):
        return self.identity

    class Meta:
        verbose_name = "Person"
        verbose_name_plural = "People"

class Student(Person):
    class Meta:
        proxy = True

class Parent(Person):
    class Meta:
        proxy = True

class Teacher(Person):
    board = GenericRelation('second_app.BoardMember') # first try
    class Meta:
        proxy = True

class BoardMember(models.Model):
    content_type = models.ForeignKey(ContentType)
    object_id = models.PositiveIntegerField()
    content_object = GenericForeignKey('content_type', 'object_id', for_concrete_model=False)
    responsabilities = models.CharField(max_length=255)

In the 'first try', deleting the Teacher record (proxy) does not delete the BoardMember record. However, in the 'second try', deleting the Person record (concrete), does delete the BoardMember record.

[Carlton Gibson]

Regression test — already passes

[Carlton Gibson]

I uploaded a regression test attempting to reproduce this. It already passes.

If we can get a failing test case reproducing the issue then we could look into it. Pending that I'm going to close.