Re: Heapless C/C++

[Shiv Shankar Dayal <shivshankar dot dayal at gmail dot com>]

> If you're using RAII consistently and correctly then the problems
> associated with heap memory go away, so you don't need to avoid the
> heap. ?If you're not using RAII correctly, your proposal won't work
> anyway and you'll leak memory. ?So what's the point?
>
> Why is it better to do dynamic allocation on the stack? ?(Answer: it's not.)
>
> You say "A record of all allocated objects by this function has to be
> kept. Also, there will be gaps or fragmentation in Stack because of
> this for which we will have to move allocated area down almost in all
> cases and sometimes up." ?You haven't got rid of heap, you've got rid
> of the stack, making using the stack as complicated as using the heap.
> ?How do you propose to move the area? ?You have to adjust all pointers
> referring to it, which is not possible in the general case (even if
> you scan the process' entire memory to look for pointer-like patterns,
> they could be obfuscated or stored in a file, or outside the process
> in other ways.) ?If the stack needs to grow to call a function, but
> the space it wants to grow into contains dynamically-allocated
> objects, what happens? ?Does the stack skip over that block,
> remembering where to skip back over it when unwinding? ?Your stack is
> no longer contiguous and must keep track of far more information. A
> stack pointer won't work anymore.
>
> There are good reasons why dynamic memory, which has unpredictable
> lifetime, is kept in a separate region from stack memory, which
> doesn't.
>
> I agree the proposal is hopeless.
>

To add more, I am trying to enforce RAII. You are not allowed to do memory
allocation at any place other than construction and deallocate it other than
destructor. Hope you get the point.

-- 
Best regards,
Shiv Shankar Dayal