About mex function problem

Hi everyone,

I recieved the code using mex function. When I run it on Matlab, it occured errors as below

Error using mex

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x0):

multiple definition of `vsnprintf'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x3b0): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x10):

multiple definition of `getc'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x3c0): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x40):

multiple definition of `putc'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x3f0): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x70):

multiple definition of `getchar'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x420): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0xa0):

multiple definition of `putchar'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x450): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0xe0):

multiple definition of `fopen64'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x490): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0xf0):

multiple definition of `ftello64'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x4a0): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x120):

multiple definition of `vsnwprintf'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x4d0): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x130):

multiple definition of `strtof'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x4e0): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x150):

multiple definition of `wcstof'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x500): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x170):

multiple definition of `_Exit'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x520): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x180):

multiple definition of `llabs'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x530): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x1a0):

multiple definition of `atoll'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x550): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x1b0):

multiple definition of `lltoa'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x560): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x1c0):

multiple definition of `ulltoa'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x570): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x1d0):

multiple definition of `wtoll'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x580): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x1e0):

multiple definition of `lltow'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x590): first defined here

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\c_mexapi_version.obj:c_mexapi_version.c:(.text+0x1f0):

multiple definition of `ulltow'

C:\Users\BAO_MA~1\AppData\Local\Temp\mex_85703934924329_1184\lbfgsC.obj:lbfgsC.c:(.text+0x5a0): first defined here

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libm.a when searching for -lm

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libmingw32.a when searching for -lmingw32

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libmoldname.a when searching for -lmoldname

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libmingwex.a when searching for -lmingwex

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libmsvcrt.a when searching for -lmsvcrt

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libuser32.a when searching for -luser32

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libkernel32.a when searching for -lkernel32

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libadvapi32.a when searching for -ladvapi32

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libshell32.a when searching for -lshell32

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libmingw32.a when searching for -lmingw32

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libmoldname.a when searching for -lmoldname

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libmingwex.a when searching for -lmingwex

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

skipping incompatible C:/HEN_HOUSE/gnu/lib\libmsvcrt.a when searching for -lmsvcrt

C:/ProgramData/MATLAB/SupportPackages/R2019b/3P.instrset/mingw_w64.instrset/bin/../lib/gcc/x86_64-w64-mingw32/6.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe:

i386 architecture of input file `C:/HEN_HOUSE/gnu/lib/dllcrt2.o' is incompatible with i386:x86-64 output

C:/HEN_HOUSE/gnu/lib/dllcrt2.o: In function `__dll_exit':

d:/src/mingw/build/runtime/../../runtime/dllcrt1.c:140: undefined reference to `_free'

d:/src/mingw/build/runtime/../../runtime/dllcrt1.c:148: undefined reference to `_fflush'

C:/HEN_HOUSE/gnu/lib/dllcrt2.o: In function `DllMainCRTStartup':

d:/src/mingw/build/runtime/../../runtime/dllcrt1.c:87: undefined reference to `_DllMain@12'

d:/src/mingw/build/runtime/../../runtime/dllcrt1.c:56: undefined reference to `_malloc'

d:/src/mingw/build/runtime/../../runtime/dllcrt1.c:67: undefined reference to `__pei386_runtime_relocator'

d:/src/mingw/build/runtime/../../runtime/dllcrt1.c:74: undefined reference to `___main'

d:/src/mingw/build/runtime/../../runtime/dllcrt1.c:59: undefined reference to `__errno'

C:/HEN_HOUSE/gnu/lib/dllcrt2.o: In function `atexit':

d:/src/mingw/build/runtime/../../runtime/dllcrt1.c:166: undefined reference to `___dllonexit'

C:/HEN_HOUSE/gnu/lib/dllcrt2.o: In function `_onexit':

d:/src/mingw/build/runtime/../../runtime/dllcrt1.c:182: undefined reference to `___dllonexit'

collect2.exe: error: ld returned 1 exit status

I tried to understand it and fixed but I did not resolve.

I also represented the code here.

#include <math.h>
#include "mex.h"

/* See lbfgs.m for details! */
/* This function may not exit gracefully on bad input! */


void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{
    /* Variable Declarations */
    
    double *s, *y, *g, *H, *d, *ro, *alpha, *beta, *q, *r;
    int nVars,nSteps,lhs_dims[2];
    double temp;
    int i,j;
    
    /* Get Input Pointers */
	
    g = mxGetDoubles(prhs[0]);
    s = mxGetDoubles(prhs[1]);
    y = mxGetDoubles(prhs[2]);
    H = mxGetDoubles(prhs[3]);
    
    /* Compute number of variables (p), rank of update (d) */
    
    nVars = mxGetDimensions(prhs[1])[0];
    nSteps = mxGetDimensions(prhs[1])[1];
    
	/* Allocated Memory for Function Variables */
    ro = mxCalloc(nSteps,sizeof(double));
	alpha = mxCalloc(nSteps,sizeof(double));
	beta = mxCalloc(nSteps,sizeof(double));
	q = mxCalloc(nVars*(nSteps+1),sizeof(double));
	r = mxCalloc(nVars*(nSteps+1),sizeof(double));
	
    /* Set-up Output Vector */
    
    lhs_dims[0] = nVars;
    lhs_dims[1] = 1;
    
    plhs[0] = mxCreateNumericArray(2,lhs_dims,mxDOUBLE_CLASS,mxREAL);
    d = mxGetDoubles(plhs[0]);
    
    /* ro = 1/(y(:,i)'*s(:,i)) */
    for(i=0;i<nSteps;i++)
    {
        temp = 0;
        for(j=0;j<nVars;j++)
        {
			temp += y[j+nVars*i]*s[j+nVars*i];
        }
        ro[i] = 1/temp;
    }
	
	/* q(:,k+1) = g */
	for(i=0;i<nVars;i++)
	{
		q[i+nVars*nSteps] = g[i];
	}

	for(i=nSteps-1;i>=0;i--)
	{
		/* alpha(i) = ro(i)*s(:,i)'*q(:,i+1) */
		alpha[i] = 0;
		for(j=0;j<nVars;j++)
		{
			alpha[i] += s[j+nVars*i]*q[j+nVars*(i+1)]; 
		}
		alpha[i] *= ro[i];

		/* q(:,i) = q(:,i+1)-alpha(i)*y(:,i) */
		for(j=0;j<nVars;j++)
		{
			q[j+nVars*i]=q[j+nVars*(i+1)]-alpha[i]*y[j+nVars*i];
		}
	}

	/*  r(:,1) = q(:,1) */
	for(i=0;i<nVars;i++)
	{
		r[i] = H[0]*q[i];
	}

	for(i=0;i<nSteps;i++)
	{
		/* beta(i) = ro(i)*y(:,i)'*r(:,i) */
		beta[i] = 0;
		for(j=0;j<nVars;j++)
		{
			beta[i] += y[j+nVars*i]*r[j+nVars*i];
		}
		beta[i] *= ro[i];

		/* r(:,i+1) = r(:,i) + s(:,i)*(alpha(i)-beta(i)) */
		for(j=0;j<nVars;j++)
		{
			r[j+nVars*(i+1)]=r[j+nVars*i]+s[j+nVars*i]*(alpha[i]-beta[i]);
		}
	}

	/* d = r(:,k+1) */
	for(i=0;i<nVars;i++)
	{
		d[i]=r[i+nVars*nSteps];
	}

	/* Free Memory */
	
	mxFree(ro);
	mxFree(alpha);
	mxFree(beta);
	mxFree(q);
	mxFree(r);
	
}

I have been using Matlab 2019b and mexw64.

Anybody can help me. Thank you so much.

Thu Nguyen

[Walter Roberson]

Your toolchain appears to be getting gcc libraries from C:/HEN_HOUSE/gnu/lib but what you have installed there is for 32 bit i386.

[thu nguyen]

Can you tell me how to fix that? Because I know a little a bit about C and mex function. This code I got from another. Thank you.

[Walter Roberson]

mex -v -setup C

and choose an appropriate compiler. As you are using MS Windows, MinGW is supported but gcc directly is not supported.

[thu nguyen]

I have aldready setup the MinGW64 Compiler (C)

and using

mex -setup C

mex lbfgsC.c

But the errors occured as I mentioned above.

[Walter Roberson]

Check your environment variables; they are possibly pointing you to an incorrect gcc installation.

[thu nguyen]

I am checking all. Thank for your recommendation.

[Bramcal]

have you been able to solve the problem?

[thu nguyen]

I have not fixed the problem yet.

Can you help me to solve this?

Thank you for your consideration.

[Rahul Pathak]

I am also facing the similar type of problem and I am working on 2019b ver.

Kindly help me.

Answer 1

[James Tursa]

This code is incorrect:

    int nVars,nSteps,lhs_dims[2];
    :
    plhs[0] = mxCreateNumericArray(2,lhs_dims,mxDOUBLE_CLASS,mxREAL);

The int type is almost certainly a 32-bit integer on your system, but for 64-bit compiles that dimension array needs to be mwSize (which probably converts to a 64-bit size_t integer type). So a mismatch. The code needs to be this:

    mwSize lhs_dims[2];