opencv compile with clang ok, with gcc not ok os x 10.9

Question

I am on OS X 10.9, with opencv-2.4.8.2 installed. I am trying to compile a simple code:

#include <stdio.h>
#include <opencv2/opencv.hpp>

using namespace cv;

int main(int argc, char** argv )
{
    if ( argc != 2 )
    {
        printf("usage: DisplayImage.out <Image_Path>\n");
        return -1;
    }

    Mat image;
    image = imread( argv[1], 1 );

    if ( !image.data )
    {
        printf("No image data \n");
        return -1;
    }
    namedWindow("Display Image", WINDOW_AUTOSIZE );
    imshow("Display Image", image);

    waitKey(0);

    return 0;
}

and can do that with clang (/usr/bin/g++ -arch x86_64 pkg-config opencv --libs test.cpp), but not with gcc 4.9 (/usr/local/bin/g++ -arch x86_64 pkg-config opencv --libs test.cpp).

This is what I get with gcc 4.9:

$ /usr/local/bin/g++ `pkg-config opencv --libs` test.cpp
Undefined symbols for architecture x86_64:
  "cv::namedWindow(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, int)", referenced from:
      _main in cc52UZjK.o
  "cv::imread(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, int)", referenced from:
      _main in cc52UZjK.o
  "cv::imshow(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, cv::_InputArray const&)", referenced from:
      _main in cc52UZjK.o
ld: symbol(s) not found for architecture x86_64
collect2: error: ld returned 1 exit status

Can anyone help me figure out why?

info about my compilers:

$ /usr/bin/gcc -v Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1 Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn) Target: x86_64-apple-darwin13.1.0 Thread model: posix

$ /usr/local/bin/gcc -v Using built-in specs. COLLECT_GCC=/usr/local/bin/gcc COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/x86_64-apple-darwin13.0.0/4.9.0/lto-wrapper Target: x86_64-apple-darwin13.0.0 Configured with: ../gcc-4.9-20131215/configure --enable-languages=c++,fortran Thread model: posix gcc version 4.9.0 20131215 (experimental) (GCC)

I believe your problem is identical to the linked question. However, I would like to applaud you for posting a question with enough information to quickly identify your problem. — Aurelius

RJVB RJVB · Accepted Answer · 2014-11-21T17:15:54

The short answer is: you cannot use GCC to build C++ code on OS X 10.9 and newer, because Apple switched to using libc++ instead of libstdc++ and GCC is incompatible with that runtime. Many attempts have been made to find a workaround, but in the end it turned out to be infeasible.

opencv compile with clang ok, with gcc not ok os x 10.9

1 Answers