I've been very use to the requirement of using a constant expression
for array size during array declaration.

I was just told that the C++ standard allows the following:

..
void foo(int n) {
int myArray[n];
for (int i = 0; i < n; myArray[i++] = 0);
}

int main() {
int arraySize = 1000;
foo(arraySize);
return 0;
}

Now, this *seems* to be just plain wrong; however, some c++ compilers
accept it, while some don't.  I thought the standard stated you must
use a constant expression.

Can anyone please tell me what the actual standard says is legal
(regardless of how compilers implement it)?

Thanks!

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* dave.lowe@gmail.com:
>
> I was just told that the C++ standard allows the following:
>
> ..
> void foo(int n) {
> int myArray[n];
> for (int i = 0; i < n; myArray[i++] = 0);
> }

That's incorrect.

It is allowed in C99 (C is not C++, and C99 is not previous
versions of C).


> Can anyone please tell me what the actual standard says is legal
> (regardless of how compilers implement it)?

n must be a compile-time integral constant, except when you allocate
the array dynamically.

--
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<dave.lowe@gmail.com> wrote in message
news:1102531235.242333.57250@f14g2000cwb.googlegroups.com...

> I was just told that the C++ standard allows the following:

> void foo(int n) {
> int myArray[n];
> for (int i = 0; i < n; myArray[i++] = 0);
> }

It doesn't.  Whoever told you that is mistaken.

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