RFR: 8339480: Build static-jdk image with a statically linked launcher [v9]

[Jiangli Zhou]

On Wed, 13 Nov 2024 01:40:23 GMT, Jiangli Zhou <jiangli at openjdk.org> wrote:

>> @jianglizhou Thank you for your assistance in figuring out the problem. I guess I throw out too much code from the hermetic-java-runtime branch when trying to minimize the changes to only build-related stuff. The jimage changes were so busy so I probably ignored them a bit too much.
>
> @magicus Just want to check if there's anything that you are waiting from me for this PR. My understanding is that you'll update the PR to fix the incremental build and debuginfo before the last review iteration. Please let me know if there are anything else. Thanks!

> @jianglizhou
> 
> > I think we would need to decide what is the dll_dir with the static JDK support and hermetic support.
> 
> From my understanding, `_sun_boot_library_path` does not have any meaning when running with static builds. As I said before, I think we really ought to take a step back, consider the wider picture, and refactor the way we interact with internal native libraries. Determining how to handle `_sun_boot_library_path` for static builds are definitely part of that work.

There might still be some usages of `_sun_boot_library_path` with static JDK. I recently made changes (in our local copy and not yet in https://github.com/openjdk/leyden/tree/hermetic-java-runtime) to use `_sun_boot_library_path` to locate the `jspawnhelper` in `<jdk>/lib` when spawning child process is needed, for supporting specific hermetic Java testing mode (without building a full hermetic image). At some point, we want to call out the supported execution modes (e.g. hermetic mode, dynamic/tradition mode, hermetic testing mode, etc) in https://docs.google.com/document/d/1LWy9vFDis5-hbJwrFUBH1rc8w8f3oL6O3sOzQXjXVUM/edit?usp=sharing as part of the ongoing discussions with Alan, Ron and others. Agreed that `_sun_boot_library_path` should be part of the bigger picture design/discussion.

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PR Comment: https://git.openjdk.org/jdk/pull/20837#issuecomment-2486244160