I am accessing some methods from unmanaged code dll using [DLLImport]
[DllImport("Foo.dll", CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Unicode)]
public static extern int CalcSome(byte[] jsonIn);
[DllImport("Foo.dll", CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Unicode)]
public static extern int GetResult(byte[] jsonOut);
When these methods are called synchronously there was no issue, but when executed parallel in a Task scheduler or Parallel.For() my application is crashing with error
Managed Debugging Assistant 'FatalExecutionEngineError' Message=Managed Debugging Assistant 'FatalExecutionEngineError' : 'The runtime has encountered a fatal error. The address of the error was at 0x74e0b428, on thread 0x390c. The error code is 0xc0000005. This error may be a bug in the CLR or in the unsafe or non-verifiable portions of user code. Common sources of this bug include user marshaling errors for COM-interop or PInvoke, which may corrupt the stack.'
I have no access to source code of Foo.dll, Can anyone help on how to identify on why this issue is happening.
PS: Both methods execute every time they are called (both Synchronous and Asynchronous) , till application crashes abruptly.