building on OS X 10.9

[psycharo-zz]

there are some problems when building for OS X 10.9 (clang-500.2.79).

It seems that it has to do primarily with linking.
Editing this line to allow not only GCC makes it possible to proceed further, but then I get undefined references to (so it seems) OpenCV (even though it is installed):

--  Has OpenCV (Image manipulation)          : Yes (System) [Version: 2.4.6.1, Has non-free: 1]

Error log:

Linking CXX shared library ../../lib/libmrpt-vision.dylib
clang: warning: argument unused during compilation: '-pthread'
Undefined symbols for architecture x86_64:
  "cv::FeatureDetector::detect(cv::Mat const&, std::vector<cv::KeyPoint, std::allocator<cv::KeyPoint> >&, cv::Mat const&) const", referenced from:
      mrpt::vision::CFeatureExtraction::extractFeaturesFAST(mrpt::utils::CImage const&, mrpt::vision::CFeatureList&, unsigned int, unsigned int, mrpt::vision::TImageROI const&, mrpt::math::CMatrixTemplate<bool> const*) const in CFeatureExtraction_FAST.cpp.o
      mrpt::vision::CFeatureExtraction::extractFeaturesSIFT(mrpt::utils::CImage const&, mrpt::vision::CFeatureList&, unsigned int, unsigned int, mrpt::vision::TImageROI const&) const in CFeatureExtraction_SIFT.cpp.o
  "cv::DescriptorExtractor::compute(cv::Mat const&, std::vector<cv::KeyPoint, std::allocator<cv::KeyPoint> >&, cv::Mat&) const", referenced from:
      mrpt::vision::CFeatureExtraction::extractFeaturesSIFT(mrpt::utils::CImage const&, mrpt::vision::CFeatureList&, unsigned int, unsigned int, mrpt::vision::TImageROI const&) const in CFeatureExtraction_SIFT.cpp.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [lib/libmrpt-vision.1.0.3.dylib] Error 1
make[1]: *** [libs/vision/CMakeFiles/mrpt-vision.dir/all] Error 2
make: *** [all] Error 2

[jlblancoc]

Thanks for the pointer: the patch for CLang is not in master.

On the linking error, I can only give these ideas:

• Build with: "VERBOSE=1 make" to see the full linker command line.
• Perhaps you have 2 conflicting versions of OpenCV in the system?
• This is not a solution, but if you don't need OpenCV in MRPT you can just check the (advanced option) DISABLE_OpenCV in CMake.

[psycharo-zz]

OK, the problem with linking was due to the fact that in OS X 10.9 standard library has changed to libc++ (whereas it is forces to be libstdc++ in mrpt). There are still some problems after that, which can be fixed by using a newer version of octomap, and substituting GNU extensions with something else (it might be a good idea not to use those at all to make the library cross-compiler compatible).
But then, I was not able to compile the hw library and some of the apps, though the tests for the libraries that do not depend on that passed OK.

[jlblancoc]

Could you please attach a patch with the fixes you had to make? Thanks.