Re: [Xen-devel] [PATCH v2] libxl: ocaml: guard x86-specific functions behind an ifdef

[Ian Campbell <Ian.Campbell@xxxxxxxxxx>]

On Tue, 2014-01-14 at 15:23 +0000, Anil Madhavapeddy wrote:

> > Perhaps CAMLlocal2 both defines and references the variables keeping
> > this issue at bay?
> 
> That's right.  CAMLlocal2 creates a stack variable and registers it with
> the garbage collector as a root (to ensure that it's not collected during
> the lifetime of the function).  This keeps it live and always used from
> the perspective of the C compiler.

Thanks.

> Yeah, I'm not aware of any compiler that doesn't respect the noreturn
> attribute and also emits unused variable warnings. I didn't modify the
> CAMLreturn in favour of minimising the x86/ARM differences, but you could
> modify the #endif to be an #else/#endif to only return on x86.  I'd prefer
> to keep these bindings as straight-line as possible for the 4.4 release
> though, and to refactor oxenstored to not depend on them at all in the
> future (it only uses a small part of libxc and these cpuid functions
> aren't used at all).

Thanks, I'm convinced by that argument, this can go in after rc2 is cut.

Release-ack: Ian Campbell

Ian.


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