[m-rev.] for review: Support building with AddressSanitizer and UndefinedBehaviorSanitizer.

[Peter Wang]

On Wed, 12 Oct 2016 12:48:51 +1100 (AEDT), Julien Fischer <jfischer at opturion.com> wrote:
> > +Likewise, pass --c-debug when building user programs.
> 
> Just using an .ll_debug grade would have the same effect and is less
> fiddly.

Thanks, I assume the rest was okay.  Committed.

Peter