Differences between .dlls in NuGet and Python versions of DirectML provider

[Levyks]

I'm trying to write a C++ application that uses the DirectML Execution Provider, I was using the onnxruntime.dll and onnxruntime_providers_shared.dll from the NuGet C# package Microsoft.ML.OnnxRuntime.DirectML and everything worked fine for the first 2 models I tried to run, but later, when trying to run a YOLO one, it didn't ran on DML, only in CUDA or CPU.

After a lot of debugging, I tried running it on python and everything worked fine, out of curiosity, I tried copying the python dlls from Python313\Lib\site-packages\onnxruntime\capi to my own C++ project, and voala, it worked!

I noticed that the Python version has 1 extra dll, DirectML.dll, that the C# one does not.

Also, Python's onnxruntime.dll has 19-ish KB, while the one from C# has 16-ish KB

What's the reason for this difference? Shouldn't both packages just be thin wrappers around the same lib?

The error I was getting was

←[1;31m2025-05-26 17:36:02.1363987 [E:onnxruntime:, inference_session.cc:2281 onnxruntime::InferenceSession::Initialize:
:<lambda_5767435f92a738c7a221df2e7c461c0f>::operator ()] Exception during initialization: D:\a\_work\1\s\onnxruntime\cor
e\providers\dml\DmlExecutionProvider\src\AbiCustomRegistry.cpp(519)\onnxruntime.dll!00007FFDB396E372: (caller: 00007FFDB
38DDB99) Exception(3) tid(7150) 80070057 ParFailed to create segmenter: Exception during initialization: D:\a\_work\1\s\
onnxruntime\core\providers\dml\DmlExecutionProvider\src\AbiCustomRegistry.cpp(519)\onnxruntime.dll!00007FFDB396E372: (ca
ller: 00007FFDB38DDB99) Exception(3) tid(7150) 80070057 Incorrect parameter.