Undefined symbols "_getnumcores", referenced from: _imhist in imhist.o

I use matlab coder to generated the C code and call the function on my MAC running Catalina. Here is the error I got:

"Undefined symbols for architecture x86_64:

"_getnumcores", referenced from: _imhist in imhist.o

"_tbbhist_uint8", referenced from: _imhist in imhist.o

ld: symbol(s) not found for architecture x86_64

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

"imhist.h":

/*

* File: imhist.h

*

* MATLAB Coder version : 4.3

* C/C++ source code generated on : 12-Nov-2019 16:11:33

*/

#ifndef IMHIST_H

#define IMHIST_H

/* Include Files */

#include <stddef.h>

#include <stdlib.h>

#include "rtwtypes.h"

#include "SkyDetection_RGB_types.h"

/* Function Declarations */

extern void imhist(const emxArray_uint8_T *varargin_1, double yout[256]);

#endif

"imhist.c":

/*

* File: imhist.c

*

* MATLAB Coder version : 4.3

* C/C++ source code generated on : 12-Nov-2019 16:11:33

*/

/* Include Files */

#include "imhist.h"

#include "SkyDetection_RGB.h"

#include "libmwgetnumcores.h"

#include "libmwtbbhist.h"

#include "rt_nonfinite.h"

#include <string.h>

/* Function Definitions */

/*

* Arguments : const emxArray_uint8_T *varargin_1

* double yout[256]

* Return Type : void

*/

void imhist(const emxArray_uint8_T *varargin_1, double yout[256])

{

double numCores;

boolean_T nanFlag;

double localBins1[256];

boolean_T rngFlag;

double localBins2[256];

double localBins3[256];

int i;

int localBins2_tmp;

if (varargin_1->size[0] == 0) {

memset(&yout[0], 0, 256U * sizeof(double));

} else {

numCores = 1.0;

getnumcores(&numCores);

if ((varargin_1->size[0] > 500000) && (numCores > 1.0)) {

nanFlag = false;

rngFlag = false;

tbbhist_uint8(&varargin_1->data[0], (double)varargin_1->size[0], (double)

varargin_1->size[0], 1.0, yout, 256.0, 256.0, &rngFlag,

&nanFlag);

} else {

memset(&yout[0], 0, 256U * sizeof(double));

memset(&localBins1[0], 0, 256U * sizeof(double));

memset(&localBins2[0], 0, 256U * sizeof(double));

memset(&localBins3[0], 0, 256U * sizeof(double));

for (i = 0; i + 4 <= varargin_1->size[0]; i += 4) {

localBins1[varargin_1->data[i]]++;

localBins2_tmp = varargin_1->data[i + 1];

localBins2[localBins2_tmp]++;

localBins2_tmp = varargin_1->data[i + 2];

localBins3[localBins2_tmp]++;

localBins2_tmp = varargin_1->data[i + 3];

yout[localBins2_tmp]++;

}

while (i + 1 <= varargin_1->size[0]) {

yout[varargin_1->data[i]]++;

i++;

}

for (i = 0; i < 256; i++) {

yout[i] = ((yout[i] + localBins1[i]) + localBins2[i]) + localBins3[i];

}

}

}

}

[Mike Hosea]

There's a doc page Code Generation for Image Processing Toolbox that might be useful, something about shared library use.

[Ashish Uthama]

I would recommend contacting support with the repro steps (source code+config that you use to generate code), including the OS info you mention and the MATLAB version.