RFR: 8335591: Fix -Wzero-as-null-pointer-constant warnings in ConcurrentHashTable

[Kim Barrett]

On Wed, 3 Jul 2024 06:56:12 GMT, Christian Hagedorn <chagedorn at openjdk.org> wrote:

>> Please review this trivial change to ConcurrentHashTable.  Initialization of
>> and assignments to the _invisible_epoch member are changed from a value of 0
>> to nullptr.  This removes some -Wzero-as-null-pointer-constant warnings when
>> building with that enabled.
>> 
>> Testing: mach5 tier1
>
> Looks good and trivial.

Thanks for review @chhagedorn

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PR Comment: https://git.openjdk.org/jdk/pull/19996#issuecomment-2205826875