Member Avatar for mindgames

Does memory allocated for built-in types (in particular int, float and double) with the new operator initialize them to 0 (or 0.0, as the case may be)? Just trying to remember. (I seem to remember that new invokes a constructor even for the built-in types, but i'm not sure).

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Member Avatar for Ancient Dragon

No.

Proof:

int main()
{
    int* n = new int;
    cout << *n << "\n";
}
Edited by Ancient Dragon because: n/a
Member Avatar for mindgames

hm, are you sure, I'm getting n as 0 with the above code? (which is what i would expect from initialization). I'm using g++ 4.3.3 btw, if it makes any difference.

Member Avatar for Ancient Dragon

The value could be anything -- I got 23 with vc++ 2008 express and 3346328 with Code::Blocks (MinGW). It all depends on what was in that memory location.

Edited by Ancient Dragon because: n/a
Member Avatar for mindgames

I guess that makes sense... thanks.
It seems we can specify an initializer in constructor style:

int * n = new int(0)

but since (from what i just read) this doesn't work with arrays, it doesn't help with what i had in mind.
Thanks

Edited by mindgames because: n/a
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