RFR: 8341553: Remove UseCompactObjectHeaders extra CDS archives [v2]

[Erik Joelsson]

On Wed, 13 Nov 2024 23:15:47 GMT, Calvin Cheung <ccheung at openjdk.org> wrote:

>> With this change, the compact object headers related CDS archives (`classes_coh.jsa` and `classes_nocoops_coh.jsa`) will not be generated by default. If the user needs them, the user can specify the `--enable-cds-archive-coh=yes` build configure option.
>> This change also modified the TestDefaultArchiveLoading.java test.
>> 
>> Testing:
>> 
>> - default build config: classes*coh.jsa CDS archives are not generated
>> - build configured with `--enable-cds-archive-coh=yes`: classes*coh.jsa CDS archives are generated
>> - build configured with `--enable-cds-archive-coh=no`: classes*coh.jsa CDS archives are not generated
>> - passed tiers 1 and 3 tests
>
> Calvin Cheung has updated the pull request incrementally with one additional commit since the last revision:
> 
>   @iklam comment

I'm a bit unsure what was actually agreed in the bug discussion. Are wanting to disable this by default for OpenJDK, requiring anyone who wants it enabled to add a new configure option, or are we only intending to change the configuration for Oracle builds? If the latter, we should just add the option `--disable-cds-archive-coh` to `jib-profiles.js` for the relevant build profiles.

make/autoconf/jdk-options.m4 line 730:

> 728:         else
> 729:           AC_MSG_RESULT([yes])
> 730:           AVAILABLE=false

This does not look correct. The `CHECK_AVAILABLE` block is meant to check if the preconditions for enabling this feature are met. Those preconditions should not change here. All you should need to do is change the default.

-------------

PR Review: https://git.openjdk.org/jdk/pull/22051#pullrequestreview-2445607153
PR Review Comment: https://git.openjdk.org/jdk/pull/22051#discussion_r1848444907