On Tue, 20 Oct 2026 21:45:14 GMT, Phil Race <[email protected]> wrote:
> The native code on macOS which initializes cached JNI refs is not thread safe. > The fix is to use the macOS dispatch_once mechanism as a lock. > The fix is essentially all in JNIUtilities.h. There's some refactoring of the > macros in there to make things a bit cleaner > and DECLARE_*_ONLY macros are added which the non-local clients now use to > declare variables. > > The problem can be demonstrated with multi-threaded initialisation, and using > -Xcheck:jni > A case which reproduces "fairly often" has been added as a test. > > --------- > - [x] I confirm that I make this contribution in accordance with the [OpenJDK > Interim AI Policy](https://openjdk.org/legal/ai). src/java.desktop/macosx/native/libawt_lwawt/awt/a11y/ColumnAccessibility.m line 37: > 35: #import "sun_lwawt_macosx_CAccessibility.h" > 36: > 37: static jclass sjc_CAccessibility = NULL; Seems all of this is unused, so it is deleted. src/java.desktop/macosx/native/libawt_lwawt/awt/a11y/ComboBoxAccessibility.m line 34: > 32: static jclass sjc_CAccessibility = NULL; > 33: > 34: static jmethodID sjm_getAccessibleName = NULL; Turns out this isn't used. So it is deleted. src/java.desktop/macosx/native/libosxapp/JNIUtilities.h line 55: > 53: > 54: #define GET_CLASS_ONLY(dst_var, cls) \ > 55: dispatch_once(&dst_var##_once, ^{ \ This change from a test for NULL to dispatch_once is the fix. The rest is just to support it. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/33481#discussion_r4330683156 PR Review Comment: https://git.openjdk.org/jdk/pull/33481#discussion_r4330679410 PR Review Comment: https://git.openjdk.org/jdk/pull/33481#discussion_r4330690966
