Re: [PATCH newlib] libc/include/malloc.h: Add prototype for GNU extension malloc_usable_size()

[Joel Sherrill <joel@rtems.org>]

On Tue, Mar 15, 2022, 1:43 PM Sebastian Huber <
sebastian.huber@embedded-brains.de> wrote:

> On 15/03/2022 16:47, Mike Frysinger wrote:
> > On 15 Mar 2022 10:16, Joel Sherrill wrote:
> >> This is not provided by the newlib malloc implementation but may
> >> be available in external implementations.
> >> ---
> >>   newlib/libc/include/malloc.h | 4 ++++
> >>   1 file changed, 4 insertions(+)
> >>
> >> diff --git a/newlib/libc/include/malloc.h b/newlib/libc/include/malloc.h
> >> index a9dc5bca6..e73095e1e 100644
> >> --- a/newlib/libc/include/malloc.h
> >> +++ b/newlib/libc/include/malloc.h
> >> @@ -137,6 +137,10 @@ extern void __malloc_lock(struct _reent *);
> >>
> >>   extern void __malloc_unlock(struct _reent *);
> >>
> >> +#if __GNU_VISIBLE
> >> +extern size_t malloc_usable_size(void *);
> >> +#endif
> >> +
> > i'm confused.  isn't this prototype already defined in this header file
> > on line 101 above where you added this ?
>
> Yes, and it is implemented by the Newlib malloc.
>

Thanks Sebastian. Good catch.

The prototype isn't wrapped by __GNU_VISIBLE. Should it be?

--joel

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