Error using Custom C Code Simulation Library with Simulink and Stateflow

I am using Matlab Stateflow to model specific processes and these processes are suppose to interact with an existing C++ library. To allow Matlab Stateflow to interact with the C++ library, I wrote a simple C interface for the library and imported the header file and the library in the Simulation Target options. Using this simple process, I was able to load the custom library in Stateflow under MacOS X and have it interact as exepected with the library.

Now I wanted to replicate this under linux, but have unfortunately had a lot of trouble and ultimately failed to get Stateflow to load the library successfully. I then created a new, proof-of-concept C library for debugging the issue only containing a single test function and was also unable to get Stateflow to load this shared library.

The error thrown by Stateflow every time:

Failed to load custom code simulation library:/home/davidk/Desktop/slprj/_slcc/qxnWz5tNfQfFLosY9yYvpC/qxnWz5tNfQfFLosY9yYvpC_cclib.so

This is the code for the proof-of-concept C library, which Stateflow also refused to load.

Header File - test.h

#ifndef TEST_H
#define TEST_H

extern void test();

#endif

C File - test.c

#include "test.h"
#include <stdio.h>


void test(){
    printf("test");
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.13)
project(test C)

set(CMAKE_BUILD_TYPE Debug)

file(GLOB SRC "*.c")
add_library(wrapper SHARED ${SRC})

add_executable(main "main.c")
target_link_libraries(main wrapper)

The executable in the CMakelists is not important, it was just a test to see, if i could successfully use the library for linking.

The folder structure is simply:

build

test.c

test.h

CMakeLists.txt

The code listed above compiles just fine and I can also run the executable without any issues.

I am using the following simulation target settings to load the library:

And this is how the function is being called from Stateflow.

More information about my setup:

I compiled and installed GCC 6.5 from source and verified that it is being used for the compilation.

I also know that the latest supported compiler version was GCC 6.3, however after a couple of tries of installing v6.3 I could not get it to work. I applied a patch detailed here: Stackoverflow, which solved the first issue and then had to apply this "Hack" (even called a Hack by the author) Github. Which also did not fix the issues I was having installing GCC 6.3.

I am also using Matlab Version R2019a but can also try a newer Version should that have a chance of helping.

This leads me to two questions:

Firstly, is it truly required to use GCC 6.3 and if that is the case, how am I expected to install this thing ?

Secondly, how do I debug Stateflows unwillingness to load my library ? In my tests, the generated library appears to be valid and I do not know how I would proceed to debug this issue ?

Thank you, David

[Martijn]

This is not Stateflow's unwillingness to load the library; the behavior which you see is standard dynamic loader behavior on Linux. The directory containing this libwrapper.so will have to be on your LD_LIBRARY_PATH for the dynamic loader to be able to load it.