OpenCV C++/C 编译错误：未定义对 'cv：：fastFree(void*)' 的引用

我试图有一个C程序调用使用OpenCV的c++文件中的函数。我可以让C文件调用c++文件中的基本整数函数并返回结果，但是每当我尝试向c++文件添加一些OpenCV代码时，我都会得到编译错误。以下是我在每个模块中的简单代码:

foo.cpp

#include <time.h>
#include "opencv2/core/core.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/core/core.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/core/mat.hpp"
#include "opencv/cv.hpp"
#include <iostream>
#ifdef _cplusplus 
extern "C" int f(int);
#endif 
using namespace std;
using namespace cv;
int f(int i)
{
cout << "CPP SON: " << i << endl;
i--;
//Mat image;
//image = imread( "image1.jpg", 1 );
//namedWindow( "image1.jpg", CV_WINDOW_AUTOSIZE );
//imshow( "image1.jpg", image );
//waitKey(0);
return i;
}

bar.c

#include <stdio.h>
int global = 0;
int f(int);
void cc(int i)
{
    global = f(i);
    /* ... */
    printf("hello from C! %d n", global);
}
int main(int argc, char *argv[]) {
    printf("this si is the C code called mainn");
    cc(32);

}

Makefile

mot : foo.o bar.o
    g++ `pkg-config --cflags opencv` -o mot `pkg-config --libs opencv` foo.o bar.o
foo.o : foo.cpp
    g++ `pkg-config --cflags opencv` -c foo.cpp `pkg-config --libs opencv` -o foo.o
bar.o : bar.c
    g++ `pkg-config --cflags opencv` -c bar.c `pkg-config --libs opencv` -o bar.o
clean : 
    rm foo.o
    rm bar.o
    rm mot

当注释掉foo.cpp文件中的所有OpenCV行时，返回以下输出:

bi@rtes4:~/Desktop$ make
g++ `pkg-config --cflags opencv` -c foo.cpp `pkg-config --libs opencv` -o foo.o
g++ `pkg-config --cflags opencv` -c bar.c `pkg-config --libs opencv` -o bar.o
g++ `pkg-config --cflags opencv` -o mot `pkg-config --libs opencv` foo.o bar.o
bi@rtes4:~/Desktop$ ./mot
this si is the C code called main
CPP SON: 32
hello from C! 31 

注释掉"Mat image;"行后会产生以下错误:

bi@rtes4:~/Desktop$ make
g++ `pkg-config --cflags opencv` -c foo.cpp `pkg-config --libs opencv` -o foo.o
g++ `pkg-config --cflags opencv` -c bar.c `pkg-config --libs opencv` -o bar.o
g++ `pkg-config --cflags opencv` -o mot `pkg-config --libs opencv` foo.o bar.o
foo.o: In function `cv::Mat::~Mat()':
foo.cpp:(.text._ZN2cv3MatD2Ev[_ZN2cv3MatD5Ev]+0x39): undefined reference to `cv::fastFree(void*)'
foo.o: In function `cv::Mat::release()':
foo.cpp:(.text._ZN2cv3Mat7releaseEv[_ZN2cv3Mat7releaseEv]+0x47): undefined reference to `cv::Mat::deallocate()'
collect2: error: ld returned 1 exit status
make: *** [mot] Error 1

有谁可以帮忙吗?事先感谢您对此事的协助，不胜感激。