Undefined symbols for architecture x86_64

[jeanbza]

Running on a mac using gcc-4.9 (also tried and got the same error with the provided xcode c++ compiler), I get this error. This is using the project as a submodule and following the README step by step. Here is my CMakeList.txt and error when I try to make. Any ideas?

cmake_minimum_required(VERSION 2.8)
project (rest_test)

ADD_SUBDIRECTORY(lib/curlcpp)
INCLUDE_DIRECTORIES(${CURLCPP_SOURCE_DIR}/include)

add_executable (rest_test rest_test.cc)

Linking CXX executable rest_test
Undefined symbols for architecture x86_64:
  "curl::curl_exception::traceback", referenced from:
      curl::curl_exception::what() in rest_test.cc.o
      curl::curl_exception::print_traceback() const in rest_test.cc.o
  "curl::curl_exception::curl_exception(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >)", referenced from:
      curl::curl_easy_exception::curl_easy_exception(CURLcode, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >) in rest_test.cc.o
  "curl::curl_exception::~curl_exception()", referenced from:
      curl::curl_easy_exception::~curl_easy_exception() in rest_test.cc.o
  "curl::curl_easy::perform()", referenced from:
      _main in rest_test.cc.o
  "curl::curl_easy::curl_easy()", referenced from:
      _main in rest_test.cc.o
  "curl::curl_easy::~curl_easy()", referenced from:
      _main in rest_test.cc.o
  "typeinfo for curl::curl_exception", referenced from:
      typeinfo for curl::curl_easy_exception in rest_test.cc.o
  "vtable for curl::curl_exception", referenced from:
      curl::curl_exception::curl_exception(curl::curl_exception const&) in rest_test.cc.o
  NOTE: a missing vtable usually means the first non-inline virtual member function has no definition.
  "_curl_easy_setopt", referenced from:
      void curl::curl_easy::add<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > >(curl::curl_pair<CURLoption, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > >) in rest_test.cc.o
      void curl::curl_easy::add<long>(curl::curl_pair<CURLoption, long>) in rest_test.cc.o
  "_curl_easy_strerror", referenced from:
      curl::curl_easy_exception::curl_easy_exception(CURLcode, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >) in rest_test.cc.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]: *** [rest_test] Error 1
make[1]: *** [CMakeFiles/rest_test.dir/all] Error 2
make: *** [all] Error 2

[jeanbza]

Additional data point - when I cd into curlcpp, I run cmake . and make and get the following:

jadekler at Jeans-MacBook-Pro in ~/workspace/git-c-rgbmatrix/lib/curlcpp on master*
$ make
Scanning dependencies of target curlcpp
[ 12%] Building CXX object src/CMakeFiles/curlcpp.dir/curl_easy.cpp.o
gcc-4.9: error: unrecognized command line option '-stdlib=libc++'
make[2]: *** [src/CMakeFiles/curlcpp.dir/curl_easy.cpp.o] Error 1
make[1]: *** [src/CMakeFiles/curlcpp.dir/all] Error 2
make: *** [all] Error 2

[JosephP91]

@jadekler it's strange. I have g++49 too and I can't reproduce this error

[susnux]

The first one is using clang

clang: error: linker ...

But the second one is using gcc, the problem here is that cmake put a clan command (-stdlib) into gcc makefile.
Try with a clean copy of curlcpp something like:

CC=gcc CXX=g++ cmake .