having a hard time with codegen, even though interactive coder works fine

While in an interactive matlab session, when I export *.m scripts to C sources and build, I do get an executable and it actually runs correctly; when I attempt to do the same thing programmatically with codegen, with another matlab script that I run with matlab in batch mode, I do get an executable, but it does not run, I just get "Bus error (core dumped)".

May I get some assistance on what matlab commands needed and where to place them?

Here are a couple of considerations:

- I provide my own main.c

- I use a dynamic library of mine that is somewhere else

Here is the script I am passing to matlab in batch mode:

function codegen_exec()

    global libname_path
    global libname_ext

    libname_path = '/path/to/mylib/parentDir';
    libname_ext = '.so';

    addpath(genpath(libname_path));

    entry_point_function = 'Main.m'

    cfg = coder.config('exe');
    cfg.TargetLang = 'C';
    cfg.TargetLangStandard = 'C99 (ISO)';
    cfg.CustomSource = 'main.c';

    example_filename = "Input.in";
    t = coder.typeof(example_filename);
    t.StringLength = Inf;     
    input_args = {t};

    codegen(entry_point_function, ...
            '-config', cfg, ...
            '-globals', {'libname_path', libname_path, 'libname_ext', libname_ext}, ...
            '-args', input_args);
end

One think I did interactively is to provide matlab coder with a test script 'launch_Main.m', that runs 'Main.m'. I don't know how to that programmatically.

What am I missing? All hints will be very much appreciated.

[Raghu Boggavarapu]

Are you loading any shared library from the libname_path ? How are you loading the library from the path ?

If possible could you share your main.c

Interactive session creates a MEX to ensure that generated code works correctly with your test bench. You can generate MEX and use coder.runTest to reproduce the results: please see the documentation here: coder.runTest - Run test replacing calls to MATLAB functions with calls to MEX functions - MATLAB

[German]

Thanks for the hint.

I am not the actual matlab user, I am just helping a designer. Browsing around the matlab UI, I discover that it can export the coder project file to a script file; so, I did that and it totally help....I just had to do was add the path to my external library.

Answer 1

[Ayush]

Hi German,

The main cause seemed to be that the path to your external library wasn't properly set in your batch script. Exporting the Coder project to a script and explicitly adding the library path before running codegen solved the problem.

Glad it worked out!