[ERROR] OpenCL JNI Library not found - Windows 11

[PreCyz]

Describe the bug

I tried to install and use tornadovm on Windows 11 according to the instruction found in youtube and official documentation. I do have 2 different laptops:

1. Asus TUF with integrated AMD Radeon(TM) Vega 8 Graphics, and additional Radeon RX 560X.
2. Dell with integrated Intel® Iris® Xe Graphics.
   I was able to compile tornadovm on both machines with the command:
   python .\bin\tornadovm-installer --jdk jdk21 --backend=opencl

On both laptops I used the following version of dependencies/libs:
Maven: 3.9.6 and 3.9.11
jdk: openjdk 21,
python: 3.13.7

When I execute a command tornado --version I do have the following output:

version=1.1.2-dev
branch=master
commit=6e29a5b

Backends installed:
         - opencl

PROBLEM: When I execute a command tornado --devices I have the following exception:

Exception in thread "main" java.lang.ExceptionInInitializerError
        at tornado.drivers.opencl@1.1.2-dev/uk.ac.manchester.tornado.drivers.opencl.OCLBackendImpl.<init>(OCLBackendImpl.java:69)
        at tornado.drivers.opencl@1.1.2-dev/uk.ac.manchester.tornado.drivers.opencl.OCLTornadoDriverProvider.createBackend(OCLTornadoDriverProvider.java:48)
        at tornado.runtime@1.1.2-dev/uk.ac.manchester.tornado.runtime.TornadoCoreRuntime.loadBackends(TornadoCoreRuntime.java:164)
        at tornado.runtime@1.1.2-dev/uk.ac.manchester.tornado.runtime.TornadoCoreRuntime.<init>(TornadoCoreRuntime.java:104)
        at tornado.runtime@1.1.2-dev/uk.ac.manchester.tornado.runtime.TornadoCoreRuntime.<clinit>(TornadoCoreRuntime.java:78)
        at java.base/java.lang.Class.forName0(Native Method)
        at java.base/java.lang.Class.forName(Class.java:421)
        at java.base/java.lang.Class.forName(Class.java:412)
        at tornado.api@1.1.2-dev/uk.ac.manchester.tornado.api.runtime.TornadoAPIProvider.loadTornadoRuntimeImpl(TornadoAPIProvider.java:48)
        at tornado.api@1.1.2-dev/uk.ac.manchester.tornado.api.runtime.TornadoRuntimeProvider.init(TornadoRuntimeProvider.java:34)
        at tornado.api@1.1.2-dev/uk.ac.manchester.tornado.api.runtime.TornadoRuntimeProvider.<clinit>(TornadoRuntimeProvider.java:29)
        at tornado.drivers.common@1.1.2-dev/uk.ac.manchester.tornado.drivers.TornadoDeviceQuery.main(TornadoDeviceQuery.java:74)
Caused by: uk.ac.manchester.tornado.api.exceptions.TornadoRuntimeException: [ERROR] OpenCL JNI Library not found
        at tornado.drivers.opencl@1.1.2-dev/uk.ac.manchester.tornado.drivers.opencl.OpenCL.<clinit>(OpenCL.java:69)
        ... 12 more

How To Reproduce

Try to built tornadoVM on Win 11 with the latest python, maven and jdk 11.

Expected behavior

I wish it works properly.

Computing system setup (please complete the following information):

• OS: Windows 11

• OpenCL and Driver versions: DELL: OpenCL 3.0,
  Intel® Graphics Driver 32.0.101.5186 for Intel® Iris® Xe Graphics,

• If applicable, PTX and CUDA Driver versions: Nvidia CUDA 13.0 and Blackwell, and intel-oneapi-base-toolkit-2025.2.1.46.

• If applicable, Level Zero & SPIR-V Versions: N/A

• TornadoVM commit id: 6e29a5b

• OS: Windows 11

• OpenCL and Driver versions: ASSUS,
  AMD Radeon(TM) Vega 8 Graphics: OpenCL 3.0, Driver version AMD for Windows 31.0.21923.1100,
  Radeon RX 560X - OpenCL 2.0, Driver version AMD for Windows 31.0.21923.11000

• If applicable, PTX and CUDA Driver versions: Nvidia CUDA 13.0 and Blackwell

• If applicable, Level Zero & SPIR-V Versions: N/A

• TornadoVM commit id: 6e29a5b

Additional context

On my Dell the command clinfo does not work. Probably it has to be added to the ENV vars somehow.
The setup works with WSL-2 on my Dell, however, I had to use Debian distro available from Microsoft Store. Ubuntu 22.04.5 LTS it did not work because of the wrong versions of the drivers.

I'm reporting this bug because it occurs on 2 independent machines with Windows 11, and with totally different graphics each.

Please help.
Cheers Paweł

[mikepapadim]

@stratika

[stratika]

hi @PreCyz, thanks for the issue. Windows is an experimental OS platform and to the best of my knowledge it has not been tested with AMD drivers yet.

My suspicion is that there is something wrong with the OpenCL driver installation. Ideally, it would be nice if you could run clinfo or any simple OpenCL program that can identify your GPU. That's because TornadoVM relies that OpenCL runtime and drivers have been installed and are working in a system. So, I would suggest to try this as a first step.

Additionally, you could run the following command to validate that the OpenCL runtime for your platform is installed:

where OpenCL.dll

Regarding your system with the Integrated Intel Iris Xe Graphics, I have installed TornadoVM on a Windows OS with this graphic card (driver version: 32.0.101.6881) and it is working. Have you installed the Intel OpenCL Runtime (See here)?

[PreCyz]

Hi @stratika ,
Thx for the response.
The command executed in Powershell

where OpenCL.dll

does not give any results.
However, I can see in my driver details (Device Manager -> Display Adapters -> Intel Iris Xe Graphics -> Properties -> Driver -> Driver Details) that the OpenCL.dll is present at the following location: C:\WINDOWS\system32\OpenCL.dll.
I update the driver to the newest version: 32.0.101.7026 and repeat the installation process. The outcome is the same for the command tornado --devices.

Caused by: uk.ac.manchester.tornado.api.exceptions.TornadoRuntimeException: [ERROR] OpenCL JNI Library not found

For the command tornado --version I got this:

(.venv) C:\Workspace\TornadoVM>tornado --version
version=1.1.2-dev
branch=master
commit=6e29a5b

Backends installed: 
         - opencl

But I double-checked the location of the OpenCL.dll. On my Windows 11 the exact location is different than I found in Driver Details. I used File Explorer to find out that the exact location is C:\Windows\System32\opencl.dll instead of C:\WINDOWS\system32\OpenCL.dll.
Then I executed the command in the command line and I got the following result

where OpenCL.dll
C:\Windows\System32\opencl.dll

which is aligned with the path from File Explorer.

Does this may cause the problem?

[natl-set]

Can you try to use https://learn.microsoft.com/en-us/sysinternals/downloads/procmon to see what dll it is looking for but didn't find ones?

[PreCyz]

Can you try to use https://learn.microsoft.com/en-us/sysinternals/downloads/procmon to see what dll it is looking for but didn't find ones?

I'm not familiar with this tool. What should I look/do exactly to find what you need? Could you pls guide me some how?