title: C++ Ubuntu makefile error
body: <p>I have a C++ application and I have created makefile for it. how,ever I am getting the following error:</p>
  
  <pre><code>/usr/bin/ld: orsProcessor.o: undefined reference to symbol 'atan@@GLIBC_2.2.5'
  //lib/x86_64-linux-gnu/libm.so.6: error adding symbols: DSO missing from command line
  collect2: error: ld returned 1 exit status
  make: *** [ors] Error 1
  </code></pre>
  
  <p>I am stuck from the past 4 hours. Can someone help me please.?</p>
  
  <p>And my Makefile looks like this:</p>
  
  <pre><code>cc=g++
  cflags = -c
  
  all: ors
  
  ors: orsMain.o orsClassifier.o orsObjectData.o orsProcessor.o
      $(CC) orsMain.o orsClassifier.o orsObjectData.o orsProcessor.o -o ors -lstdc++
  
  orsMain.o: orsMain.cpp
        $(CC) -lhighgui.so -limgproc.so -lcore.so $(cflags) orsMain.cpp -o orsMain.o -lstdc++
  
  orsClassifier.o: orsClassifier.cpp
           $(CC) -lhighgui.so -limgproc.so -lcore.so $(cflags) orsClassifier.cpp -o orsClassifier.o -lstdc++ -lm
  
  orsObjectData.o: orsObjectData.cpp
           $(CC) -lhighgui.so -limgproc.so -lcore.so $(cflags) orsObjectData.cpp -o orsObjectData.o -lstdc++ -lm
  
  
  orsProcessor.o: orsProcessor.cpp
          $(CC) -lhighgui.so -limgproc.so -lcore.so $(cflags)  orsProcessor.cpp -o orsProcessor.o -lstdc++ -lm
  
  clean:
      rm -rf *.o *~ ors
  
  #ORSObjectRecognition.o: ORSObjectRecognition.cpp
  #           $(CC) $(cflags) ORSObjectRecognition.cpp
  </code></pre>