참조를 통한 동적 메모리 할당은 안되는 건가요?

/*////////////////원본
cNode* cRedBlackTree::treeInsert(cNode* &t, cNode* &p, int d)
{
	if (t == nil)
	{
		t = (cNode*)malloc(sizeof(cNode));
		t->key = d;
		t->left = nil;
		t->right = nil;
		t->parent = p;
		t->color = RED;
	}
	else if (d < t->key)
	{
		t->left = treeInsert(t->left, t, d);
	}
	else if (d > t->key)
	{
		t->right = treeInsert(t->right, t, d);
	}
 
	return t;
}
*/////////////////원본
//////////////////수정본
void cRedBlackTree::treeInsert(cNode* &t, cNode* p, int d)
{
	while (t != nil)
	{
		p = t;
 
		if (d < t->key)
			t = t->left;
		else if (d > t->key)
			t = t->right;
	}
 
	t = (cNode*)malloc(sizeof(cNode));
	t->key = d;
	t->left = nil;
	t->right = nil;
	t->parent = p;
	t->color = RED;
 
	//balanceInsert(t);
 
	while (t->parent != nil)
		t = t->parent;
}
/////////////////////수정본
void cRedBlackTree::treeInsert(int d)
{
	treeInsert(root, nil, d);      ///원본에서는 root = treeInsert(root, nil, d);
}