Re: [Xen-devel] [PATCH] xen: add macro for defining variable length array in public headers

[Juergen Gross <jgross@xxxxxxxx>]

On 30.08.19 16:21, Jan Beulich wrote:
> On 30.08.2019 10:32, Juergen Gross wrote:
> > --- a/xen/include/public/xen.h
> > +++ b/xen/include/public/xen.h
> > @@ -53,6 +53,15 @@ DEFINE_XEN_GUEST_HANDLE(uint64_t);
> >   DEFINE_XEN_GUEST_HANDLE(xen_pfn_t);
> >   DEFINE_XEN_GUEST_HANDLE(xen_ulong_t);
> >   
> > +/* Define a variable length array (depends on compiler). */
> > +#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
> > +#define __XEN_VARLEN_ARRAY_SIZE
> > +#elif defined(__GNUC__)
> > +#define __XEN_VARLEN_ARRAY_SIZE  0
> > +#else
> > +#define __XEN_VARLEN_ARRAY_SIZE  1 /* variable size */
> > +#endif
> To be in line with the intentions, the C90 standard, and io/ring.h
> I'd suggest to use FLEX instead of VARLEN. Furthermore, especially
> in a public header, two double leading underscores need to go away.
>
> And then, with FLEX in the name, SIZE isn't really appropriate
> anymore. Therefore I see three possible names: XEN_FLEXIBLE_ARRAY,
> XEN_FLEX_ARRAY_DIMENSION (possibly just _DIM at its end), or
> XEN_FLEX_ARRAY_DESIGNATOR.
Okay to the "FLEX" part, but the "XEN_" prefix is not working due to
compat header generation (that will result in COMPAT_ prefix in the
compat headers).

So any other ideas for a sensible prefix?


Juergen


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel