Review Request: 7193406 - Clean-up JDK Build Warnings in java.util,

Doug Lea dl at
Fri Aug 24 13:02:23 UTC 2012

Vitaly Davidovich wrote:

> So it sounds like avoiding these locals is basically trying to work 
> around current compiler limitations, rather than something more fundamental.

If javac did even a smidgen of optimization, this problem would
also go away.

> I'm also curious if someone has actually noticed any perf degradation in 
> hot code when adding locals like this (Doug? :)).  If not (but perf 
> tests were done), then I'm not sure it's worth worrying about.

Of course, I have measured actual performance problems -- otherwise
I would not be bringing up this issue :-) Not every case is a
problem, but there are some cases that matter, and it is not a
good idea to invite people to rewrite, just for the sake of warning
suppression, code that explicitly chose not to introduce redundant locals.


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