Windows compile fixes

src/voxels/ChunksController.cpp

@@ -10,7 +10,7 @@
 #include <iostream>
 #include <limits.h>
 
-#ifdef _WIN32
+#if defined(_WIN32) && defined(__MINGW32__)
 #define _WIN32_WINNT 0x0501
 #include <mingw.thread.h>
 #else

src/voxels/ChunksLoader.h

@@ -1,12 +1,12 @@
 #ifndef VOXELS_CHUNKSLOADER_H_
 #define VOXELS_CHUNKSLOADER_H_
 
-#ifdef _WIN32
+#if defined(_WIN32) && defined(__MINGW32__)
 #define _WIN32_WINNT 0x0501
 #include <mingw.thread.h>
 #else
 #include <thread>
-#endif
+#endif  // _WIN32 && __MINGW32__
 
 #include <atomic>
 

src/window/Window.cpp

@@ -1,9 +1,9 @@
 #include <iostream>
+#include "Window.h"
 #include <GL/glew.h>
 #include <GLFW/glfw3.h>
-#include "Window.h"
 
-GLFWwindow* Window::window;
+GLFWwindow* Window::window = nullptr;
 uint Window::width = 0;
 uint Window::height = 0;