r225116 - Volatile reads are side-effecting operations, but in the general case of access through a volatile-qualified type, we're not certain of the underlying object's side-effects on access.

[Joerg Sonnenberger]

On Sat, Jan 03, 2015 at 05:00:13PM -0000, Aaron Ballman wrote:
> Treat volatile accesses as "maybe" instead of "definite" side effects
> for the purposes of warning on evaluations in an unevaluated context.
> No longer diagnose on idiomatic code like:
> 
> int * volatile v;
> (void)sizeof(*v);

Thanks!

Joerg