RFR: 8200550: Xcode 9.3 produce warning on heapRegionSet.hpp (original) (raw)

Thomas Schatzl thomas.schatzl at oracle.com
Mon Apr 9 07:05:36 UTC 2018

Hi,

On Mon, 2018-04-09 at 02:55 -0400, Kim Barrett wrote:

> > NOTPRODUCT/#ifndef PRODUCT is the wrong choice, being contrary > > to to the intent of an optimize build to be similar in > > performance characteristics to a product build. > > In my understanding there is an additional clause in that sentence: > "[...] to a product build, including some extra verification". > > There is lots of similar verification that uses > PRODUCTRETURN/#ifndef PRODUCT that also already changes > performance characteristics for an optimized build. > See the other PRODUCTRETURN uses (I can find 107 in just the gc > directory) in this and other files.

That's not my understanding from discussions with Jon Masamitsu (who was the only person I knew of to regularly use and care about "optimized" builds). But it is certainly true there is a lot of code that violates that rule. I occasionally wonder whether anyone would care or notice if we killed off "optimized" builds; we don't test that mode, with the result that it is often broken.

I agree that we may probably just remove optimized builds for the above stated reasons, but that is another discussion :)

> So yes, I recommend removing this capability in this instance. This > verification does not seem to be any different than any other. > > Not sure if this capability is too expensive or not (this is > typically a bit fuzzy), but in the worst case one can use > NOTDEBUGRETURN.

Since it was previously only under ASSERT, I'm leaving it that way. New webrevs: full: http://cr.openjdk.java.net/~kbarrett/8200550/open.01/ incr: http://cr.openjdk.java.net/~kbarrett/8200550/open.01.inc/

looks good.

Thanks, Thomas

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