Octave sample code failing to compile in g++? - c++

Question

I'm attempting to get the Octave C++ code here to compile in g++ (Ubuntu/Linaro 4.6.4-1ubuntu1~12.04) 4.6.4).
This trimmed version of the above will compile in g++:
#include <iostream>
#include <octave/oct.h>
using namespace std;
int main() {
// Matrix L=Matrix(2,2);
return 0;
}
but if I unremark out the line Matrix L=Matrix(2,2); then compile with g++ temp.cpp it gives the error message:
/tmp/ccTa3Am5.o: In function `Array2<double>::~Array2()':
temp.cpp:(.text._ZN6Array2IdED2Ev[_ZN6Array2IdED5Ev]+0x1f): undefined reference to `Array<double>::~Array()'
/tmp/ccTa3Am5.o: In function `Array<double>::Array(dim_vector const&)':
temp.cpp:(.text._ZN5ArrayIdEC2ERK10dim_vector[_ZN5ArrayIdEC5ERK10dim_vector]+0x26): undefined reference to `Array<double>::get_size(dim_vector const&)'
/tmp/ccTa3Am5.o:(.rodata._ZTV5ArrayIdE[vtable for Array<double>]+0x10): undefined reference to `Array<double>::~Array()'
/tmp/ccTa3Am5.o:(.rodata._ZTV5ArrayIdE[vtable for Array<double>]+0x18): undefined reference to `Array<double>::~Array()'
collect2: ld returned 1 exit status
I'm unsure why. Perhaps I'm missing an #include, perhaps I don't have an appropriate file installed, perhaps I'm not linking to the appropriate library, or perhaps I'm misusing Octave in some way.
Question: Why is this failing to compile? How can I fix it?
It compiles fine if I use mkoctfile --link-stand-alone temp.cpp as indicated at the above site, however, I'd like to use g++ if possible, since I eventually want to be able to call Octave functions from another program I've written in C++.

Answer 1

As indicated in my comment a simple example can be found in this Howto. So in your case a simple way to achieve compilation will be creating a makefile as follows:
makefile:
all: temp
clean:
-rm temp.o temp
temp: temp.o
mkoctfile --link-stand-alone -o temp temp.o
temp.o: temp.cpp
g++ -c -I$(OCTAVE_INCLUDE)
-I$(OCTAVE_INCLUDE)octave -o temp.o temp.cpp
$(OCTAVE_INCLUDE) is an environment variable that should be set to your octave include path (e.g. /usr/include/octave-x.x.xx). Then you can simply compile and link your test application using the command make all.

Answer 2

You need to link to the octave library. If the library is octave.a:
g++ -loctave temp.cpp

Answer 3

Add the library directories to your link command:
your-local-path\octave-x.x.xx\lib\
your-local-path\octave-x.x.xx\lib\octave\x.x.xx\
mkoctfile -L"\your-path\octave-x.x.xx\lib" -L"\your-path\octave-x.x.x\lib\octave\x.x.xx" --link-stand-alone temp.cpp
For cxx11 linker errors:
Converting std::__cxx11::string to std::string
"If you get linker errors about undefined references to symbols that involve types in the std::__cxx11 namespace or the tag [abi:cxx11] then it probably indicates that you are trying to link together object files that were compiled with different values for the _GLIBCXX_USE_CXX11_ABI macro. This commonly happens when linking to a third-party library that was compiled with an older version of GCC."
Defining the following macro before including any standard library headers should fix your problem:
#define _GLIBCXX_USE_CXX11_ABI 0