cmake: 
-- The C compiler identification is GNU 7.3.0
-- The CXX compiler identification is GNU 7.3.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Found OpenGL: /usr/lib/x86_64-linux-gnu/libOpenGL.so   
-- Found GLUT: /usr/lib/x86_64-linux-gnu/libglut.so  
-- Configuring done
-- Generating done
-- Build files have been written to: /out

make: 
Scanning dependencies of target p3_part1
[ 25%] Building CXX object CMakeFiles/p3_part1.dir/main.cpp.o
[ 50%] Linking CXX executable p3_part1
[ 50%] Built target p3_part1
Scanning dependencies of target p3_part2
[ 75%] Building CXX object CMakeFiles/p3_part2.dir/WinMain.cpp.o
In file included from /in/WinMain.cpp:3:0:
/in/util.h:5:13: error: #elif with no expression
 #elif _WIN32
             ^
/in/util.h:12:1: error: 'LRESULT' does not name a type; did you mean 'FREEGLUT'?
 LRESULT CALLBACK WndProc (HWND hWnd, UINT message,
 ^~~~~~~
 FREEGLUT
/in/util.h:42:20: error: variable or field 'EnableOpenGL' declared void
 void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC)
                    ^~~~
/in/util.h:42:20: error: 'HWND' was not declared in this scope
/in/util.h:42:31: error: 'HDC' was not declared in this scope
 void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC)
                               ^~~
/in/util.h:42:36: error: 'hDC' was not declared in this scope
 void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC)
                                    ^~~
/in/util.h:42:41: error: 'HGLRC' was not declared in this scope
 void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC)
                                         ^~~~~
/in/util.h:42:48: error: 'hRC' was not declared in this scope
 void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC)
                                                ^~~
/in/util.h:68:21: error: variable or field 'DisableOpenGL' declared void
 void DisableOpenGL (HWND hWnd, HDC hDC, HGLRC hRC)
                     ^~~~
/in/util.h:68:21: error: 'HWND' was not declared in this scope
/in/util.h:68:32: error: 'HDC' was not declared in this scope
 void DisableOpenGL (HWND hWnd, HDC hDC, HGLRC hRC)
                                ^~~
/in/util.h:68:41: error: 'HGLRC' was not declared in this scope
 void DisableOpenGL (HWND hWnd, HDC hDC, HGLRC hRC)
                                         ^~~~~
/in/WinMain.cpp:5:1: error: 'LRESULT' does not name a type; did you mean 'FREEGLUT'?
 LRESULT CALLBACK WndProc (HWND hWnd, UINT message,
 ^~~~~~~
 FREEGLUT
/in/WinMain.cpp:7:20: error: variable or field 'EnableOpenGL' declared void
 void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC);
                    ^~~~
/in/WinMain.cpp:7:20: error: 'HWND' was not declared in this scope
/in/WinMain.cpp:7:31: error: 'HDC' was not declared in this scope
 void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC);
                               ^~~
/in/WinMain.cpp:7:36: error: 'hDC' was not declared in this scope
 void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC);
                                    ^~~
/in/WinMain.cpp:7:41: error: 'HGLRC' was not declared in this scope
 void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC);
                                         ^~~~~
/in/WinMain.cpp:7:48: error: 'hRC' was not declared in this scope
 void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC);
                                                ^~~
/in/WinMain.cpp:8:21: error: variable or field 'DisableOpenGL' declared void
 void DisableOpenGL (HWND hWnd, HDC hDC, HGLRC hRC);
                     ^~~~
/in/WinMain.cpp:8:21: error: 'HWND' was not declared in this scope
/in/WinMain.cpp:8:32: error: 'HDC' was not declared in this scope
 void DisableOpenGL (HWND hWnd, HDC hDC, HGLRC hRC);
                                ^~~
/in/WinMain.cpp:8:41: error: 'HGLRC' was not declared in this scope
 void DisableOpenGL (HWND hWnd, HDC hDC, HGLRC hRC);
                                         ^~~~~
/in/WinMain.cpp:13:12: error: expected initializer before 'WinMain'
 int WINAPI WinMain (HINSTANCE hInstance,
            ^~~~~~~
CMakeFiles/p3_part2.dir/build.make:62: recipe for target 'CMakeFiles/p3_part2.dir/WinMain.cpp.o' failed
make[2]: *** [CMakeFiles/p3_part2.dir/WinMain.cpp.o] Error 1
CMakeFiles/Makefile2:104: recipe for target 'CMakeFiles/p3_part2.dir/all' failed
make[1]: *** [CMakeFiles/p3_part2.dir/all] Error 2
Makefile:83: recipe for target 'all' failed
make: *** [all] Error 2