On Mon, 1 Sep 2025 05:31:43 GMT, Amit Kumar <[email protected]> wrote:
> Originally Reported in OpenJ9, fix by @AditiS11 present here: > https://github.com/ibmruntimes/openj9-openjdk-jdk25/pull/32 > > These test failure were reported in OpenJ9 (x86), I can't reproduce on my > system (s390x): > > java/foreign/TestFill.java > java/foreign/TestSegments.java > java/foreign/TestSegmentBulkOperationsContentHash.java > java/foreign/TestStringEncoding.java > java/foreign/TestVarArgs.java > > > > ```java > // Always allocate at least some memory so that zero-length segments > have distinct > // non-zero addresses. > alignedSize = Math.max(1, alignedSize); > > > Here minimum-allocated size will be 1, which is incorrect because > > > private static void initNativeMemory(long address, long byteSize) { > for (long i = 0; i < byteSize; i += Long.BYTES) { > UNSAFE.putLongUnaligned(null, address + i, 0); > } > } > > `initNativeMemory()` is going to write Long. I had a deeper look at this and this specific issue can happen only when the `byteSize` is 0 for example when calling Arena.allocate(). The `testZeroLengthNativeSegment()` test method in `test/jdk/java/foreign/TestSegments.java` already covers this code path and exercises this bug. So I think it's fine if you don't add any additional test as part of this PR. I just have one more review comment which I'll add inline. ------------- PR Comment: https://git.openjdk.org/jdk/pull/27027#issuecomment-3243788621
