False negative in contract support

[sonalmahajan15]

Below is a case of false negative when using non-literals. Replacing return x with return nil, works as expected

func fooReturn(x *int) *int {
	if x == nil {
		return x
	}
	return new(int)
}

func barReturn1(n int) {
	b1 := fooReturn(nil)
	print(*b1) // Expected: ERROR!
}