Fixed GCC warnings.

src/x11_fullscreen.c

@@ -323,7 +323,7 @@ struct _glfwResolution
 int _glfwPlatformGetVideoModes(GLFWvidmode* list, int maxcount)
 {
     int count, k, l, r, g, b, rgba, gl;
-    int depth, screen;
+    int depth, screen = DefaultScreen(_glfwLibrary.X11.display);
     XVisualInfo* vislist;
     XVisualInfo dummy;
     int viscount, rgbcount, rescount;

src/x11_init.c

@@ -470,8 +470,8 @@ static void initGammaRamp(void)
     // RandR gamma support is only available with version 1.2 and above
     if (_glfwLibrary.X11.RandR.available &&
         (_glfwLibrary.X11.RandR.majorVersion > 1 ||
-         _glfwLibrary.X11.RandR.majorVersion == 1 &&
-         _glfwLibrary.X11.RandR.minorVersion >= 2))
+         (_glfwLibrary.X11.RandR.majorVersion == 1 &&
+          _glfwLibrary.X11.RandR.minorVersion >= 2)))
     {
         // FIXME: Assumes that all monitors have the same size gamma tables
         // This is reasonable as I suspect the that if they did differ, it

src/x11_time.c

@@ -30,6 +30,7 @@
 
 #include "internal.h"
 
+#include <sys/time.h>
 #include <time.h>