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Posted: **Mon Jun 22, 2009 7:33 am**

Like the subject says, I surprised with dynamic memory allocation on stack!
I tried this code:

int main(int argc, char *argv[])
{
   int n;
   scanf("%d",&n);

  int vector[n];
}

And it worked!!
I'm using dev-cpp on Windows Vista ( gcc (GCC) 3.4.2 (mingw-special) )
( looking the asm code I could see that it does it by calling alloca() )
What I want to know is if this kind of memory allocation is allowed by ANSI C?
And, is there any other kind of stack dynamic memory allocation?

Posted: **Mon Jun 22, 2009 7:39 am**

Variable Length Arrays (VLA's), introduced with C99.

See http://www.geocities.com/vijoeyz/articl ... /pna2.html.

*Nods*

Yes, C99 has much to offer beyond what K&R told you. It's worth checking it out.

Posted: **Mon Jun 22, 2009 7:43 am**

Thanks a lot!
I'll take a look on that article!

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Surprised with dynamic memory allocation on stack

Surprised with dynamic memory allocation on stack

Re: Surprised with dynamic memory allocation on stack

Re: Surprised with dynamic memory allocation on stack