S-function crashes when accessing external dll compiled with /CLR

Hello, I have been trying to use .NET libraries in simulink. I am testing it with the c++/cli dll that calls the .NET assembly and am trying to include this dll into the s-function. The code for the dll is below.

Inside the s-function I use #include "ManagedDll.dll" ,and then call the two exposed functions in the mdlOutputs.

The s-function compiles normally (with with -lManagedDll) , but when running it causes a crash with "Fatal Exception" and the stack trace seems to point to the CLR.dll

If I remove the call to the dll functions everything runs normally, no crashes.

Is simulink not compatible with C++/CLI?

#include "stdafx.h"

#include "ManagedDll.h"

// ManagedDll.h

#pragma once

using namespace System;
using namespace System::Reflection;


namespace ManagedDll {

	public ref class DoWork
	{

	public:int CSharpIntSum(int arg1, int arg2)
	{
		ManagedCSharp::ManagedClass^ mcs = gcnew ManagedCSharp::ManagedClass(1, 2);
		return mcs->IntSum(arg1, arg2);
	}
	public:float CSharpFloatSum(float arg1, float arg2)
	{
		ManagedCSharp::ManagedClass^ mcs = gcnew ManagedCSharp::ManagedClass(1, 2);
		return mcs->FloatSum(arg1, arg2);
	}

	};

}

__declspec(dllexport) int GetIntResult(int arg1, int arg2)
{
	ManagedDll::DoWork work;
	return work.CSharpIntSum(arg1, arg2);
}


__declspec(dllexport) float GetFloatResult(float arg1, float arg2)
{
	ManagedDll::DoWork work;
	return work.CSharpFloatSum(arg1, arg2);
}

Answer 1

[Maneet Kaur Bagga]

Hi Pavel,

As per my understanding of the question the code provided is an example of a C++/CLI DLL that wraps around a .NET assembly called "ManagedDll". The DLL exposes two functions, "GetIntResult" and "GetFloatResult", which internally call functions from the "ManagedDll" assembly. This code demonstrates how to create a C++/CLI DLL that acts as a bridge between native C++ code and managed .NET code.

The issue being faced is an S-Function feature.Simulink is primarily designed to work with C and C++ code, and it may not have direct support for C++/CLI (Common Language Infrastructure). C++/CLI is a specific technology that allows to mix native C++ code with managed .NET code.The crash might be caused due to the custom .NET file and not due to the MATLAB generated files.

For better understanding of the S-Function block please refer to the MATLAB Documentation below.

https://www.mathworks.com/help/simulink/sfg/what-is-an-s-function.html

Thank You!

Maneet Bagga