issue with past-the-end pointer

[Vincent Blanchon]

Hi all,

In this proposal https://github.com/golang/proposal/blob/master/design/24543-non-cooperative-preemption.md, it is mentioned past-the-end pointer and the fact it should be avoided. My assumption is that it could lead to a bad memory tracking/cleaning since the write barriers keep track of the change in the pointers. Is that correct?

Thank you

[Ian Lance Taylor]

On Wed, Mar 18, 2020 at 9:33 AM Vincent Blanchon
<blanchon...@gmail.com> wrote:
>
> In this proposal https://github.com/golang/proposal/blob/master/design/24543-non-cooperative-preemption.md, it is mentioned past-the-end pointer and the fact it should be avoided. My assumption is that it could lead to a bad memory tracking/cleaning since the write barriers keep track of the change in the pointers. Is that correct?

Pretty much, yes. A past-the-end pointer looks like a pointer to the
next object, and the write barrier can't tell the difference.

Ian

[Vincent Blanchon]

Thank you Ian!