On 2019-10-21 09:43, Per Liden wrote:
Hi Erik,
On 10/18/19 2:54 PM, Erik Joelsson wrote:
Hello Leo,
When removing a JVM feature from the VALID_JVM_FEATURES list, it
needs to be added to the DEPRECATED_JVM_FEATURES list. Deprecated
here means removed here, but configure will still accept the argument
(with a warning).
Are we really treating the list of JVM feature as a public/stable API,
or is there some other reason for this? Would the plan be to remove it
from the DEPRECATED_JVM_FEATURES in JDK 15?
Note that this is an issue for building only. A feature listed as
deprecated in the build will not propagate outside the build system.
We are basically treating the configure command line arguments as a
"stable API". The intention is that a command line on a build script
should not cause a build failure due to an unknown argument. We have
traditionally had 2-3 major releases before removing deprecated command
line options.
/Magnus
cheers,
Per
Otherwise build changes look good.
/Erik
On 2019-10-18 02:38, David Holmes wrote:
Hi Leo,
cc'ing build-dev. I think there is a process you need to follow to
remove VM features from the build system. And build folk need to
check all build changes anyway.
Thanks,
David
On 18/10/2019 6:20 pm, Leo Korinth wrote:
Hi,
Here is a patch that removes the CMS GC.
I have neither tested arm nor ppc; I hope my changes to those .ad
files are correct, if someone can test those architectures, that
would be great.
Please take an extra look at
CollectedHeap::check_for_non_bad_heap_word_value, it was buggy
before (but never called), It is now called (and hopefully correct).
I have tried to remove most parts of CMS. I have not made it a goal
to remove all traces of CMS. I guess there are much more to
cleanup, and suggestions of more to remove are welcomed. I think
more complicated cleanups should be dealt with in separate
enhancements.
Not fully addressed in code, but an issue that has to be dealt
with, how do I obsolete -Xconcgc and -Xnoconcgc? I believe the
option should be obsoleted, though I do not know if we have any
precedence obsoleting -X options.
My patch prints:
$ java -Xconcgc -jar Notepad.jar
Java HotSpot(TM) 64-Bit Server VM warning: -Xconcgc uses
UseConcMarkSweepGC
I guess that is not enough for being obsolete, compare with:
$ java -XX:UseConcMarkSweepGC -jar Notepad.jar
Java HotSpot(TM) 64-Bit Server VM warning: Ignoring option
UseConcMarkSweepGC; support was removed in 14.0
Bug:
https://bugs.openjdk.java.net/browse/JDK-8232365
Webrev:
http://cr.openjdk.java.net/~lkorinth/8232365/00
Testing:
tier 1-5.
Thanks,
Leo
