[RFA] Ensure result of make_cleanup is never NULL.

[Pedro Alves]

On 04/18/2012 01:43 AM, Doug Evans wrote:

> btw, I thought about making cleanup_sentinel const here, for a bit of
> extra robustness.


Won't that mean you'd need to cast the constness out in most, if
not all places that use it?

-- 
Pedro Alves