RFR (S) 8140483: Atomic*FieldUpdaters final fields should be trusted

[John Rose]

On Oct 27, 2015, at 4:19 AM, Aleksey Shipilev <aleksey.shipilev at oracle.com> wrote:
> 
> Hi,
> 
> I'd like to start a formal review for the change:
>   https://bugs.openjdk.java.net/browse/JDK-8140483
> 
> The feedback was overwhelmingly positive so far. Some suggested we use
> compiler control and/or maintain the list of trusted classes. I still
> think it is an overkill for the fix at hand, and we should instead wait
> for the wholesale final field optimizations.

This is a good point-fix for a specific problem with a specific set of performance-sensitive classes.

I prefer class-based exceptions (b), as more accurate and less likely to be subverted by "surprising" package additions.  (The check for Serializable, does, however, cut out the main "surprise" effect.)

— John

P.S. Fixing finals is one of those slippery-slope problems, like fixing the class file format (or, for that matter, fixing our broken kitchen stove, which ended up with a much more expensive kitchen remodel, because we couldn't fix just the stove).