[PATCH] c-user: Document rtems_extension_create()

[Gedare Bloom]

On Fri, Apr 17, 2020 at 11:33 AM Sebastian Huber
<sebastian.huber at embedded-brains.de> wrote:
>
> On 17/04/2020 19:30, Gedare Bloom wrote:
>
> On Fri, Apr 17, 2020 at 2:11 AM Sebastian Huber
> <sebastian.huber at embedded-brains.de> wrote:
>
> Close #3953.
> ---
>  c-user/user_extensions.rst | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/c-user/user_extensions.rst b/c-user/user_extensions.rst
> index c3bd1c6..89b86fd 100644
> --- a/c-user/user_extensions.rst
> +++ b/c-user/user_extensions.rst
> @@ -466,6 +466,8 @@ DIRECTIVE STATUS CODES:
>
>       * - ``RTEMS_SUCCESSFUL``
>         - extension set created successfully
> +     * - ``RTEMS_INVALID_ADDRESS``
> +       - ``table`` or ``id`` are NULL
>
> This is OK, I guess there are no other valid checks that are made on
> addresses usually.
>
> As we continue to improve our processes, it may be worth considering
> the use of well-defined regions and symbol ranges to provide
> additional sanity checks on address pointers, maybe.  I'm just
> ruminating.
>
> Actually I think that all these NULL pointer checks are completely superfluous. However, since most RTEMS APIs have them I thought it would be consistent to add this also here.

I agree in the sense that they should probably be DEBUG filtered. They
are overhead/wasteful for well-developed applications.