Re: [Xen-devel] [PATCH] pub-headers: reduce C99 dependencies

[Julien Grall <julien.grall@xxxxxxx>]

Hi Jan,

On 28/09/2016 05:00, Jan Beulich wrote:
> For consumers not using (fully) C99-aware compilers, limit the number
> of places where tweaking of the headers would be necessary: Introduce
> and use xen_mk_ullong(), allowing its helper macro to be overridden at
> once.
>
> For now don't touch public/io/, which also has a few offenders.
>
> The need to include xen.h in hvm/e820.h demonstrates that it is a bad
> idea to include public headers first thing - arch/x86/hvm/mtrr.c needs
> adjustment just because of this.
>
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
> ---
> I wonder why all those ARM constants carry the ULL suffix despite only
> two of them actually exceeding 32 significant bits.
I am not the author of the code, but I think it was to declare all the 
constants of a given set uniformed.
For instance all the GUEST_* constants are used to define the layout of 
the guest. This may be shuffle in this future (this is not part of ABI) 
and if we suffix with ULL only 64-bits constant, it would be a call to 
forget when moving from a 32-bit to 64-bit value.
Cheers,

--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel