RFR: 8346394: Bundled freetype library needs to have JNI_OnLoad for static builds [v3]

[Erik Joelsson]

On Tue, 17 Dec 2024 18:16:55 GMT, Magnus Ihse Bursie <ihse at openjdk.org> wrote:

>> All JDK native libraries needs to have a proper `JNI_OnLoad`, set either by `DEF_STATIC_JNI_OnLoad` or `DEF_JNI_OnLoad`. This is so that in a static build, the JVM can recognize that the library is already loaded, and does not try to load a (non-existent) external library.
>> 
>> Our bundled version of freetype is missing such a marker.
>> 
>> This turns out to be a problem just on Windows, since the `System.loadLibrary("freetype")` code in `FontManagerNativeLibrary` is only executed on Windows. However, the cost of including this in the bundled versions on all platforms is very small, and it is a safeguard for any future changes. In practice, freetype bundling is only enabled on Windows anyways.
>
> Magnus Ihse Bursie has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Document purpose of java_freetype.c

Marked as reviewed by erikj (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/22791#pullrequestreview-2509734898