RFR: JDK-8274435: EXCEPTION_ACCESS_VIOLATION in BFSClosure::closure_impl [v2]

[Erik Österlund]

On Thu, 30 Sep 2021 21:54:05 GMT, Ekaterina Vergizova <evergizova at openjdk.org> wrote:

>> Hi,
>> please review this small change that prevents EXCEPTION_ACCESS_VIOLATION on some Windows machines.
>> The crash is intermittently reproducible on win32 client jvm when running e.g. jdk/jfr/jcmd/TestJcmdDumpPathToGCRoots.java test.
>> It is caused by BitSet::get_fragment_bits method which returns null for the newly initialized BitSet if granule (= addr >> _bitmap_granularity_shift) is equal to 0.
>> 
>> Testing:
>> jdk/jfr/* with win32 and win64 builds, no crashes or regression after the fix.
>
> Ekaterina Vergizova has updated the pull request incrementally with one additional commit since the last revision:
> 
>   JDK-8274435: EXCEPTION_ACCESS_VIOLATION in BFSClosure::closure_impl

Looks good.

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PR: https://git.openjdk.java.net/jdk/pull/5736