Call delete [] on array of std :: aligned_storage_t

I have a class, myclass, that does not have a default constructor. I wanted to new an array my_array of myclass, so here is what I did:

• I newed an equally-sized array my_tmp_array of std :: aligned_storage_t <sizeof(myclass), alignof(myclass)>.
• I looped over every item in the array, calling new (&(my_tmp_array[i])) myclass(/*params*/);.
• I set my_array = reinterpret_cast <myclass *> (my_tmp_array);

So far so good. Everything works nicely and all is good. Now, I naively expected that by calling delete [] my_array; I would have successfully deleted the array, but no dice: I get a pointer being freed was not allocated. I noticed that the value of the pointer that is actually being fed to free is a couple of bytes smaller than that of my_array.

I guess this has to do with the whole alignment issue, but I am confused. I expected std :: aligned_storage_t <sizeof(myclass), alignof(myclass)> would be stored in memory just as myclass.

Disclaimer: I am aware of the existence of std :: vectors. I would like, however, to take the chance to learn something here. What have I done wrong?