vmTestbase/vm/mlvm/hiddenloader/stress/byteMutation/Test.java fails on Windows aarch64

[Grinder](https://ci.adoptium.net/job/Grinder/parambuild/?SDK_RESOURCE=upstream&TARGET=hotspot_custom&TEST_FLAG=&UPSTREAM_TEST_JOB_NAME=&DOCKER_REQUIRED=false&ACTIVE_NODE_TIMEOUT=5&VENDOR_TEST_DIRS=&EXTRA_DOCKER_ARGS=&TKG_OWNER_BRANCH=adoptium%3Amaster&OPENJ9_SYSTEMTEST_OWNER_BRANCH=eclipse%3Amaster&PLATFORM=aarch64_windows&GENERATE_JOBS=true&KEEP_REPORTDIR=true&PERSONAL_BUILD=false&ADOPTOPENJDK_REPO=https%3A%2F%2Fgithub.com%2Fadoptium%2Faqa-tests.git&RERUN_ITERATIONS=0&LABEL=&EXTRA_OPTIONS=&CUSTOMIZED_SDK_URL=&BUILD_IDENTIFIER=&ADOPTOPENJDK_BRANCH=v1.0.13-release&LIGHT_WEIGHT_CHECKOUT=false&NON_AQA_TEST_REPOS=&USE_JRE=false&ARTIFACTORY_SERVER=&KEEP_WORKSPACE=false&USER_CREDENTIALS_ID=&JDK_VERSION=21&ITERATIONS=1&VENDOR_TEST_REPOS=&JDK_REPO=https%3A%2F%2Fgithub.com%2Fadoptium%2Fjdk21u&OPENJ9_BRANCH=master&OPENJ9_SHA=&JCK_GIT_REPO=&VENDOR_TEST_BRANCHES=&OPENJ9_REPO=https%3A%2F%2Fgithub.com%2Feclipse-openj9%2Fopenj9.git&UPSTREAM_JOB_NAME=build-scripts%2Fjobs%2Frelease%2Fjobs%2Fjdk21u%2Fjdk21u-release-windows-aarch64-temurin&CLOUD_PROVIDER=&PLATFORM_AND_MACHINE=&CUSTOM_TARGET=vmTestbase%2Fvm%2Fmlvm%2Fhiddenloader%2Fstress%2FbyteMutation%2FTest.java&VENDOR_TEST_SHAS=&JDK_BRANCH=jdk-21.0.11%2B9_adopt&TEST_IMAGES_REQUIRED=true&LABEL_ADDITION=&ARTIFACTORY_REPO=&ARTIFACTORY_ROOT_DIR=&UPSTREAM_TEST_JOB_NUMBER=&DOCKERIMAGE_TAG=&JDK_IMPL=hotspot&TEST_TIME=&SSH_AGENT_CREDENTIAL=&AUTO_DETECT=true&SLACK_CHANNEL=aqavit-bot&DYNAMIC_COMPILE=false&ADOPTOPENJDK_SYSTEMTEST_OWNER_BRANCH=adoptium%3Amaster&APPLICATION_OPTIONS=&CUSTOMIZED_SDK_URL_CREDENTIAL_ID=eclipse_temurin_bot_email_and_token&ARCHIVE_TEST_RESULTS=false&OPENJDK_SHA=&NUM_MACHINES=&RERUN_FAILURE=false&BUILD_LIST=openjdk&USE_TESTENV_PROPERTIES=true&UPSTREAM_JOB_NUMBER=18&STF_OWNER_BRANCH=adoptium%3Amaster&TIME_LIMIT=25&JVM_OPTIONS=&PARALLEL=None)
```
17:05:26 STDOUT:
17:05:26 [16:5:12.809] ### TRACE 1: RNG seed = 351052243703212786 (0x4df3027db88aaf2)
17:05:26 For random generator using seed: 351052243703212786
17:05:26 To re-run test with same seed value please add "-Djdk.test.lib.random.seed=351052243703212786" to command line.
17:05:26 [16:5:12.857] ### TRACE 1: If the JVM crashes then the class file causing the crash is saved as *_*__HiddenkTestee01.class
17:05:26 STDERR:
17:05:26 rerun:
17:05:26 cd 'C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\scratch\0' && \
17:05:26 PATH='D:\Program Files (Arm)\Microsoft\jdk-17.0.6.10-hotspot\bin;C:\cygwin64\bin;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0;C:\Windows\System32\OpenSSH;C:\Users\adoptopenjdk\AppData\Local\Microsoft\WindowsApps;C:\Strawberry\perl\bin;C:\Program Files\Git\cmd;C:\openjdk\jdk-8\bin;C:\apache-ant\apache-ant-1.10.15\bin;C:\rust\bin;C:\Program Files\IcedTeaWEB\bin;C:\Program Files (x86)\Windows Kits\10\Windows Performance Toolkit;C:\Program Files (x86)\Incredibuild;C:\cygwin64\bin;C:\Users\jenkins\AppData\Local\Microsoft\WindowsApps;C:\Users\jenkins\.dotnet\tools' \
17:05:26 SystemDrive=C: \
17:05:26 SystemRoot='C:\Windows' \
17:05:26 TEMP='C:\Users\jenkins\AppData\Local\Temp' \
17:05:26 TMP='C:\Users\jenkins\AppData\Local\Temp' \
17:05:26 windir='C:\Windows' \
17:05:26 CLASSPATH='C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\classes\0\vmTestbase\vm\mlvm\hiddenloader\stress\byteMutation\Test.d;C:\Users\jenkins\workspace\Grinder\aqa-tests\openjdk\openjdk-jdk\test\hotspot\jtreg\vmTestbase\vm\mlvm\hiddenloader\stress\byteMutation;C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\classes\0\vmTestbase;C:\Users\jenkins\workspace\Grinder\aqa-tests\openjdk\openjdk-jdk\test\hotspot\jtreg\vmTestbase;C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\classes\0\test\lib;C:\Users\jenkins\workspace\Grinder\aqa-tests\openjdk\openjdk-jdk\test\lib;C:\Users\jenkins\workspace\Grinder\jvmtest\openjdk\jtreg\lib\javatest.jar;C:\Users\jenkins\workspace\Grinder\jvmtest\openjdk\jtreg\lib\jtreg.jar' \
17:05:26 'C:\Users\jenkins\workspace\Grinder\jdkbinary\j2sdk-image\bin\java' \
17:05:26 -Dtest.vm.opts='-ea -esa -Xmx512m' \
17:05:26 -Dtest.tool.vm.opts='-J-ea -J-esa -J-Xmx512m' \
17:05:26 -Dtest.compiler.opts= \
17:05:26 -Dtest.java.opts= \
17:05:26 -Dtest.jdk='C:\Users\jenkins\workspace\Grinder\jdkbinary\j2sdk-image' \
17:05:26 -Dcompile.jdk='C:\Users\jenkins\workspace\Grinder\jdkbinary\j2sdk-image' \
17:05:26 -Dtest.timeout.factor=8.0 \
17:05:26 -Dtest.nativepath='C:\Users\jenkins\workspace\Grinder\jdkbinary\openjdk-test-image\hotspot\jtreg\native' \
17:05:26 -Dtest.root='C:\Users\jenkins\workspace\Grinder\aqa-tests\openjdk\openjdk-jdk\test\hotspot\jtreg' \
17:05:26 -Dtest.name=vmTestbase/vm/mlvm/hiddenloader/stress/byteMutation/Test.java \
17:05:26 -Dtest.verbose=Verbose[p=NONE,f=FULL,e=FULL,t=true,m=false] \
17:05:26 -Dtest.file='C:\Users\jenkins\workspace\Grinder\aqa-tests\openjdk\openjdk-jdk\test\hotspot\jtreg\vmTestbase\vm\mlvm\hiddenloader\stress\byteMutation\Test.java' \
17:05:26 -Dtest.main.class=vm.mlvm.hiddenloader.stress.byteMutation.Test \
17:05:26 -Dtest.src='C:\Users\jenkins\workspace\Grinder\aqa-tests\openjdk\openjdk-jdk\test\hotspot\jtreg\vmTestbase\vm\mlvm\hiddenloader\stress\byteMutation' \
17:05:26 -Dtest.src.path='C:\Users\jenkins\workspace\Grinder\aqa-tests\openjdk\openjdk-jdk\test\hotspot\jtreg\vmTestbase\vm\mlvm\hiddenloader\stress\byteMutation;C:\Users\jenkins\workspace\Grinder\aqa-tests\openjdk\openjdk-jdk\test\hotspot\jtreg\vmTestbase;C:\Users\jenkins\workspace\Grinder\aqa-tests\openjdk\openjdk-jdk\test\lib' \
17:05:26 -Dtest.classes='C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\classes\0\vmTestbase\vm\mlvm\hiddenloader\stress\byteMutation\Test.d' \
17:05:26 -Dtest.class.path='C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\classes\0\vmTestbase\vm\mlvm\hiddenloader\stress\byteMutation\Test.d;C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\classes\0\vmTestbase;C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\classes\0\test\lib' \
17:05:26 -Dtest.class.path.prefix='C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\classes\0\vmTestbase\vm\mlvm\hiddenloader\stress\byteMutation\Test.d;C:\Users\jenkins\workspace\Grinder\aqa-tests\openjdk\openjdk-jdk\test\hotspot\jtreg\vmTestbase\vm\mlvm\hiddenloader\stress\byteMutation;C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\classes\0\vmTestbase;C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\classes\0\test\lib' \
17:05:26 -Dtest.modules=java.base/jdk.internal.misc \
17:05:26 --add-modules java.base \
17:05:26 --add-exports java.base/jdk.internal.misc=ALL-UNNAMED \
17:05:26 -ea \
17:05:26 -esa \
17:05:26 -Xmx512m \
17:05:26 '-Djava.library.path=C:\Users\jenkins\workspace\Grinder\jdkbinary\openjdk-test-image\hotspot\jtreg\native' \
17:05:26 com.sun.javatest.regtest.agent.MainWrapper 'C:\Users\jenkins\workspace\Grinder\aqa-tests\TKG\output_1776269095728\hotspot_custom_0\work\vmTestbase\vm\mlvm\hiddenloader\stress\byteMutation\Test.d\main.0.jta' -stressIterationsFactor 100000
17:05:26
17:05:26 TEST RESULT: Failed. Unexpected exit from test [exit code: -1073741819]
```

Assisted-by: copilot
**April 2026 failure** ([#7008 comment](https://github.com/adoptium/aqa-tests/issues/7008#issuecomment-4253374708)):
- Job: [Test_openjdk21_hs_extended.openjdk_aarch64_windows_rerun #63](https://ci.adoptium.net/job/Test_openjdk21_hs_extended.openjdk_aarch64_windows_rerun/63/) — `hotspot_vmTestbase_vm_mlvm_0` — passed: 43; **failed: 1** (`vmTestbase/vm/mlvm/hiddenloader/stress/byteMutation/Test.java`)
- Grinder rerun: [#16980](https://ci.adoptium.net/job/Grinder/16980/) — ⚠️ UNSTABLE

No prior occurrences were found in the October 2025 or January 2026 JDK-21 triage comments for this specific test on windows-aarch64. This appears to be a new intermittent failure — the test involves stress-testing bytecode mutation via hidden class loaders, and windows-aarch64 is a cross-compiled platform which may have additional instability.

Start with vmTestbase/vm/mlvm/hiddenloader/stress/byteMutation/Test.java and the supplied Grinder rerun, then compare the Windows aarch64 failure logs with a passing run. Investigate the unexpected exit code -1073741819 during the hidden-class bytecode-mutation stress test. Done means identifying and correcting the platform-specific failure, or documenting a reproducible cause and confirmed workaround.

Written by the indexing model from the issue text.