RFR: JDK-8275703: System.loadLibrary fails on Big Sur for libraries hidden from filesystem [v2]

[Maurizio Cimadamore]

On Wed, 27 Oct 2021 17:27:41 GMT, Mandy Chung <mchung at openjdk.org> wrote:

>> On, macOS 11.x, system libraries are loaded from dynamic linker cache.  The libraries are no longer present on the filesystem.   `NativeLibraries::loadLibrary` checks for the file existence before calling `JVM_LoadLibrary`.   Such check no longer applies on Big Sur.   This proposes that on macOS >= 11, it will skip the file existence check and attempt to load a library for each path from java.library.path and system library path.
>
> Mandy Chung has updated the pull request incrementally with two additional commits since the last revision:
> 
>  - Adjust parsing os.version to handle no dot version in case it's allowed
>  - Exclude building exeLibraryCache.c on other platforms except macOS

This came up on panama-dev a bunch of time now. In fact, in the panama use case this would make sense for other systems as well. For instance on linux systems, there's a bunch of known library names in gnu/lib-names.h which programs can depend on, but for which System::load/loadLibrary cannot be used - as they are neither library names, nor paths - for instance "libm.so.6".

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Marked as reviewed by mcimadamore (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/6127