mex file generation failed

i'm trying to generate mex file for my project. I'm always getting the following error and i don't understand it well and also how to fix it:

[11/11] /usr/bin/xcrun -sdk macosx12.1 clang build/maci64/simulation.o build/maci64/simulation_test_data.o build/maci64/rt_nonfinite.o build/maci64/simulation_test_initialize.o build/maci64/simulation_test_terminate.o build/maci64/simulation_test.o build/maci64/_coder_simulation_test_api.o build/maci64/_coder_simulation_test_mex.o build/maci64/_coder_simulation_test_info.o build/maci64/c_mexapi_version.o -Wl,-twolevel_namespace -undefined error -arch x86_64 -mmacosx-version-min=10.14 -Wl,-syslibroot,/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.1.sdk -bundle -L"/Applications/MATLAB_R2020b.app/bin/maci64" -lmx -lmex -lmat -lc++ -Wl,-rpath,@loader_path -o simulation_test_mex.mexmaci64 -lemlrt -lcovrt -lut -lmwmathutil -Wl,-exported_symbols_list,simulation_test_mex.map

FAILED: simulation_test_mex.mexmaci64

/usr/bin/xcrun -sdk macosx12.1 clang build/maci64/simulation.o build/maci64/simulation_test_data.o build/maci64/rt_nonfinite.o build/maci64/simulation_test_initialize.o build/maci64/simulation_test_terminate.o build/maci64/simulation_test.o build/maci64/_coder_simulation_test_api.o build/maci64/_coder_simulation_test_mex.o build/maci64/_coder_simulation_test_info.o build/maci64/c_mexapi_version.o -Wl,-twolevel_namespace -undefined error -arch x86_64 -mmacosx-version-min=10.14 -Wl,-syslibroot,/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.1.sdk -bundle -L"/Applications/MATLAB_R2020b.app/bin/maci64" -lmx -lmex -lmat -lc++ -Wl,-rpath,@loader_path -o simulation_test_mex.mexmaci64 -lemlrt -lcovrt -lut -lmwmathutil -Wl,-exported_symbols_list,simulation_test_mex.map

Undefined symbols for architecture x86_64:

"_speed_control_M", referenced from:

_simulate in simulation.o

"_speed_control_initialize", referenced from:

_simulate in simulation.o

"_speed_control_step", referenced from:

_simulate in simulation.o

ld: symbol(s) not found for architecture x86_64

clang: error: linker command failed with exit code 1 (use -v to see invocation)

The command i used to build and generate the mex file is shown as follow an:

codegen simulation_test -args {1,2} simulation.c -report

simulation_test.m is my matlab function and looks as follow:

function r_sim=simulation_test(KR,KI)

%#codegen

r_sim= zeros(size(0:0.01:0.25));

coder.cinclude('simulation.h');

coder.ceval('simulate',KR,KI, coder.wref(r_sim));

end

my simulation.c file looks as follow:

#include "simulation.h"

void simulate(double KR,double KI,double* r_sim)

{

speed_control_initialize();

/* Simulating the model step behavior (in non real-time) to

* simulate model behavior at stop time.

*/

while ((rtmGetErrorStatus(speed_control_M) == (NULL)) && !rtmGetStopRequested

(speed_control_M)) {

speed_control_step(KR,KI,r_sim);

}

}

now i'm not caring about the simulation result but the proper mex file generation.

I have been looking for a solution to my problem for 2 days and don't know how to move on. I tried things from Internet without success. I will appreciate your help very much.

Answer 1

[Mark McBroom]

It looks like you are missing the .c file that contains the code for speed_control_initialize() and speed_control_step()

[Emmanuel Walter Djeutsop Sonkoua]

@Mark McBroom yes you have right, i was not given my .c file were those functions are defined. So i just add it to the codegen command and the mex file is generated properly now. thanks !!!

[Emmanuel Walter Djeutsop Sonkoua]

Now i getting my mex file crashed when i attempt to run it. And Matlab also get close.

then i checked the dump file and the abort() function seems to be called during the execution of the mex file.

as you can see in the code above i have the function declaration in simulation.h:

void simulation(double KR, double KI, double * r_sim)

the simulation results have to be save in r_sim which is initialized in the matlab function simulation_test (r_sim= zeros(size(0:0.01:0.25));)

my question is: should i initialize the pointer r_sim within my c function before writing data to that adress?

i thouht that coder.wref(r_sim) was doing that.

Answer 2

[Mark McBroom]

See the bottom of this page for instructions on how to use a source code debugger on C Mex Functions.

https://www.mathworks.com/help/simulink/sfg/debugging-c-mex-s-functions.html#:~:text=%20Debug%20the%20MEX%20file%3A%20%201%20Start,Press%20Ctrl%2BC%20to%20open%20the%20debugger.%20See%20More.