Is there a way in C++ to allocate a variable amount of stack space at
run-time?

void complex_maths_operation(const int num_rows, double* vector)
{
double temp[num_rows];
....
}

The obvious answer is to use the heap... but if this isn't an option.

Adam wrote:

> Is there a way in C++ to allocate a variable amount of stack space at
> run-time?

Well, there is the class std::stack, but I doubt that you are referring to
that. However, other than that, C++ doesn't define anything called "stack".

Adam wrote:
> Is there a way in C++ to allocate a variable amount of stack space at
> run-time?
>
> void complex_maths_operation(const int num_rows, double* vector)
> {
> double temp[num_rows];
> ....
> }
>
> The obvious answer is to use the heap... but if this isn't an option.

Recurse. Your base case can depend on a run-time variable.

Adam wrote:
> Is there a way in C++ to allocate a variable amount of stack space at
> run-time?
>
> void complex_maths_operation(const int num_rows, double* vector)
> {
> double temp[num_rows];
> ....
> }
>
> The obvious answer is to use the heap... but if this isn't an option.
> ...

There's no C++-standard way to do that.

If you don't mind going outside the limits of C++ standard, look up the 'alloca'
function. It does exactly what you want but has some limitations, which might be
(or might not be) critical in your case.

--
Best regards,
Andrey Tarasevich

Thanks Andrey,

Yes, 'alloca' style allocation is what I was looking for.
This sort of behavor is supported by Ada and I've become fond of it.

Adam

"Andrey Tarasevich" <andreytarasevich@hotmail.com> wrote in message
news:OPqdnWZLEKaxhFzanZ2dnUVZ_ubinZ2d@comcast.com. ..
> Adam wrote:
>> Is there a way in C++ to allocate a variable amount of stack space at
>> run-time?
>>
>> void complex_maths_operation(const int num_rows, double* vector)
>> {
>> double temp[num_rows];
>> ....
>> }
>>
>> The obvious answer is to use the heap... but if this isn't an option.
>> ...
>
> There's no C++-standard way to do that.
>
> If you don't mind going outside the limits of C++ standard, look up the
> 'alloca' function. It does exactly what you want but has some limitations,
> which might be (or might not be) critical in your case.
>
> --
> Best regards,
> Andrey Tarasevich

Adam wrote:

> Yes, 'alloca' style allocation is what I was looking for.
> This sort of behavor is supported by Ada and I've become fond of it.

Don't allocate too much with alloca(), on most systems, there's a lot
less stack space than heap space available with default settings.