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explicit instantiation vs std::vector template how: gotcha

icegood (63)
Just continuation of closed theme
http://cplusplus.com/forum/general/83798/
Now have a kind of library with <algorithms> involved. Crashes again.

main file ex.cpp:
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#include "sub.h"
int main(int argc, const char **argv)
{
  CMain<TCbDoubleBridgeBase_Candidates> cs;
  //
  return 0;
}


and library: sub.cpp+sub.h. Want to do instantiation encapsulated:
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#ifndef sub_h
#define sub_h
#include <vector>
#include <iostream>
using namespace std;

struct TCbDoubleBridgeBase_Candidates
{
public:
  int I;
  int J;
  //
  TCbDoubleBridgeBase_Candidates() {}
  TCbDoubleBridgeBase_Candidates(int AI, int AJ)
  {
    I=AI;
    J=AJ;
  };
  inline bool operator < (const TCbDoubleBridgeBase_Candidates &other) const
  {
    int i=I-other.I;
    //
    if (i<0)
      return true;
    else if (i==0)
      return J<other.J;
    else 
      return false;
  }
};

template <typename T>
class CMain
{
public:
  CMain();
  std::vector<T> data;
};

#ifndef ExplicitInstantiation
  #include "sub.cpp"
#endif
#endif //sub_h 


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#ifndef sub_cpp
#define sub_cpp
#include "sub.h"
#include <algorithm>

template <typename T>
CMain<T>::CMain()
{
  data.reserve(100);
  std::sort(data.begin(), data.end(), 
      [] (TCbDoubleBridgeBase_Candidates lp1, TCbDoubleBridgeBase_Candidates lp2)
      {
        return lp1<lp2;
      });
}

#ifdef ExplicitInstantiation
template class std::vector<TCbDoubleBridgeBase_Candidates>;
template class CMain<TCbDoubleBridgeBase_Candidates>;
#endif
#endif //sub_cpp



Now with 3 commands

g++ -c sub.cpp -std=gnu++11
g++ -c ex.cpp -std=gnu++11
g++ sub.o ex.o -std=gnu++11

everything is OK. But with next 3 commands:

g++ -c sub.cpp -std=gnu++11 -fno-implicit-templates -DExplicitInstantiation
g++ -c ex.cpp -std=gnu++11 -fno-implicit-templates -DExplicitInstantiation
g++ sub.o ex.o -std=gnu++11 -fno-implicit-templates -DExplicitInstantiation


i got linker errors. So how to create instantiation with encapsulation?

Last edited on
icegood (63)
anyone has same?
guestgulkan (2942)
anyone has same?

Don't know - not tried it yet.
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