youcompleteme_build.sh

function python_finder {
  python_library="-DPYTHON_LIBRARY="
  python_include="-DPYTHON_INCLUDE_DIR="

  # python_library="/Users/ldong/.pyenv/versions/2.7.6/lib/python2.7/config"
  # python_include="/Users/ldong/.pyenv/versions/2.7.6/lib/python2.7/site-packages"
  # The CMake 'FindPythonLibs' Module does not work properly.
  # So we are forced to do its job for it.
  python_prefix=$(python-config --prefix | sed 's/^[ \t]*//')
  if [ -f "${python_prefix}/Python" ]; then
    python_library+="${python_prefix}/Python"
    python_include+="${python_prefix}/Headers"
  else
    which_python=$(python -c 'import sys;print(sys.version)' | sed 's/^[ \t]*//')
    which_python="python${which_python:0:3}"
    lib_python="${python_prefix}/lib/lib${which_python}"
    if [ -f "${lib_python}.a" ]; then
      python_library+="${lib_python}.a"
    # This check is for for CYGWIN
    elif [ -f "${lib_python}.dll.a" ]; then
      python_library+="${lib_python}.dll.a"
    else
      python_library+="${lib_python}.dylib"
    fi
    python_include+="${python_prefix}/include/${which_python}"
  fi

  python_library="-DPYTHON_LIBRARY="
  python_include="-DPYTHON_INCLUDE_DIR="

  python_prefix="/System/Library/Frameworks/Python.framework/Versions/2.7"
  python_library+="${python_prefix}/Python"
  python_include+="${python_prefix}/Headers"

  #python_library="/Users/ldong/.pyenv/versions/2.7.6/lib/python2.7/config"
  #python_include="/Users/ldong/.pyenv/versions/2.7.6/lib/python2.7/site-packages"
  #python_library+="/Users/ldong/.pyenv/versions/2.7.6/lib/libpython2.7.a"
  #python_include+="/Users/ldong/.pyenv/versions/2.7.6/include/python2.7"

  echo "${python_library} ${python_include}"
}

My version of YCM

/Users/ldong/.pyenv/versions/2.7.6/lib/libpython2.7.a
/Users/ldong/.pyenv/versions/2.7.6/lib/python2.7/site-packages/Users/ldong/.pyenv/versions/2.7.6/include/python2.7

New version of YCM

-DPYTHON_LIBRARY=/Users/ldong/.pyenv/versions/2.7.6/lib/libpython2.7.a 
-DPYTHON_INCLUDE_DIR=/Users/ldong/.pyenv/versions/2.7.6/include/python2.7

mine

/var/folders/jk/8dtll3q94tl33p291bw8_76c0000gn/T/ycm_build.XXXXXX.kO5BbIb2 ~/.vim/bundle/vim_youcompleteme
Path
/Users/ldong/.pyenv/versions/2.7.6/lib/libpython2.7.a /Users/ldong/.pyenv/versions/2.7.6/lib/python2.7/site-packages/Users/ldong/.pyenv/versions/2.7.6/include/python2.7