Re: Garbage Collection - The Trash Begins To Pile Up

Walter Bright <>
2 Jan 2007 10:36:40 -0500
Nemanja Trifunovic wrote:

Walter Bright wrote:

Nemanja Trifunovic wrote:

Walter Bright wrote:

You've a potential resource leak every time you use operator new, and a
potential dangling pointer problem every time you use RAII. For


just store a reference to an RAII stack allocated std::string into a
global map.

And who would do that, and why?

Stuffing a symbol table, for one.

So to stuff a symbol table, you would create a string on the stack, and
put a reference to it to a global map? Sorry, I think you know better
than that.

That's true, who would ever code a bug into their program? <g>

Sure, the language allows such a thing,
but if we are going to talk about real life situations this is simply
not an issue.

I write real life programs. It's an issue.

You write as if nobody ever needs to use the free store. I find that

Who said anything about not using free store? You imply it is a common
thing to create an object on the stack and put a pointer (or reference)
to it in a global map.

No, I said it was a common problem with using RAII objects.

*That* is what I don't consider a real life
issue. Where is the free store in the example you mention?

That was an example of a potential problem using RAII.

For the potential problem with the free store, just throw an exception:

    Object *o = new Object();
    foo(); // foo() throws an exception, o is now leaked
    return o;

You've got such potential every time you use free store. And every time
you use RAII, you have the potential for a dangling pointer.

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