Determining if the Q_WS_WIN exist failed with the following output:
Change Dir: /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp

Run Build Command:/usr/bin/gmake "cmTryCompileExec4259369566/fast"
/usr/bin/gmake -f CMakeFiles/cmTryCompileExec4259369566.dir/build.make CMakeFiles/cmTryCompileExec4259369566.dir/build
gmake[1]: Entering directory '/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp'
/usr/bin/cmake -E cmake_progress_report /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CMakeFiles 1
Building CXX object CMakeFiles/cmTryCompileExec4259369566.dir/CheckSymbolExists.cxx.o
/usr/bin/x86_64-pc-linux-gnu-g++    -DNDEBUG -mtune=native -O2 -msse3 -pipe   -I/usr/include/qt4    -o CMakeFiles/cmTryCompileExec4259369566.dir/CheckSymbolExists.cxx.o -c /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx
/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx: In function 'int main(int, char**)':
/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx:8:19: error: 'Q_WS_WIN' was not declared in this scope
   return ((int*)(&Q_WS_WIN))[argc];
                   ^
CMakeFiles/cmTryCompileExec4259369566.dir/build.make:60: recipe for target 'CMakeFiles/cmTryCompileExec4259369566.dir/CheckSymbolExists.cxx.o' failed
gmake[1]: *** [CMakeFiles/cmTryCompileExec4259369566.dir/CheckSymbolExists.cxx.o] Error 1
gmake[1]: Leaving directory '/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp'
Makefile:117: recipe for target 'cmTryCompileExec4259369566/fast' failed
gmake: *** [cmTryCompileExec4259369566/fast] Error 2

File /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx:
/* */
#include <QtCore/qglobal.h>

int main(int argc, char** argv)
{
  (void)argv;
#ifndef Q_WS_WIN
  return ((int*)(&Q_WS_WIN))[argc];
#else
  (void)argc;
  return 0;
#endif
}

Determining if the Q_WS_QWS exist failed with the following output:
Change Dir: /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp

Run Build Command:/usr/bin/gmake "cmTryCompileExec2060185000/fast"
/usr/bin/gmake -f CMakeFiles/cmTryCompileExec2060185000.dir/build.make CMakeFiles/cmTryCompileExec2060185000.dir/build
gmake[1]: Entering directory '/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp'
/usr/bin/cmake -E cmake_progress_report /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CMakeFiles 1
Building CXX object CMakeFiles/cmTryCompileExec2060185000.dir/CheckSymbolExists.cxx.o
/usr/bin/x86_64-pc-linux-gnu-g++    -DNDEBUG -mtune=native -O2 -msse3 -pipe   -I/usr/include/qt4    -o CMakeFiles/cmTryCompileExec2060185000.dir/CheckSymbolExists.cxx.o -c /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx
/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx: In function 'int main(int, char**)':
/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx:8:19: error: 'Q_WS_QWS' was not declared in this scope
   return ((int*)(&Q_WS_QWS))[argc];
                   ^
CMakeFiles/cmTryCompileExec2060185000.dir/build.make:60: recipe for target 'CMakeFiles/cmTryCompileExec2060185000.dir/CheckSymbolExists.cxx.o' failed
gmake[1]: *** [CMakeFiles/cmTryCompileExec2060185000.dir/CheckSymbolExists.cxx.o] Error 1
gmake[1]: Leaving directory '/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp'
Makefile:117: recipe for target 'cmTryCompileExec2060185000/fast' failed
gmake: *** [cmTryCompileExec2060185000/fast] Error 2

File /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx:
/* */
#include <QtCore/qglobal.h>

int main(int argc, char** argv)
{
  (void)argv;
#ifndef Q_WS_QWS
  return ((int*)(&Q_WS_QWS))[argc];
#else
  (void)argc;
  return 0;
#endif
}

Determining if the Q_WS_MAC exist failed with the following output:
Change Dir: /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp

Run Build Command:/usr/bin/gmake "cmTryCompileExec2904989990/fast"
/usr/bin/gmake -f CMakeFiles/cmTryCompileExec2904989990.dir/build.make CMakeFiles/cmTryCompileExec2904989990.dir/build
gmake[1]: Entering directory '/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp'
/usr/bin/cmake -E cmake_progress_report /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CMakeFiles 1
Building CXX object CMakeFiles/cmTryCompileExec2904989990.dir/CheckSymbolExists.cxx.o
/usr/bin/x86_64-pc-linux-gnu-g++    -DNDEBUG -mtune=native -O2 -msse3 -pipe   -I/usr/include/qt4    -o CMakeFiles/cmTryCompileExec2904989990.dir/CheckSymbolExists.cxx.o -c /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx
/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx: In function 'int main(int, char**)':
/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx:8:19: error: 'Q_WS_MAC' was not declared in this scope
   return ((int*)(&Q_WS_MAC))[argc];
                   ^
CMakeFiles/cmTryCompileExec2904989990.dir/build.make:60: recipe for target 'CMakeFiles/cmTryCompileExec2904989990.dir/CheckSymbolExists.cxx.o' failed
gmake[1]: *** [CMakeFiles/cmTryCompileExec2904989990.dir/CheckSymbolExists.cxx.o] Error 1
gmake[1]: Leaving directory '/var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp'
Makefile:117: recipe for target 'cmTryCompileExec2904989990/fast' failed
gmake: *** [cmTryCompileExec2904989990/fast] Error 2

File /var/tmp/portage/media-gfx/freecad-0.13.1830/work/freecad-0.13.1830_build/CMakeFiles/CMakeTmp/CheckSymbolExists.cxx:
/* */
#include <QtCore/qglobal.h>

int main(int argc, char** argv)
{
  (void)argv;
#ifndef Q_WS_MAC
  return ((int*)(&Q_WS_MAC))[argc];
#else
  (void)argc;
  return 0;
#endif
}