With gcc-4.4.7, cmake-3.2.3, opencv-3.2.0 and gtk-2.18.9-10.el6 I get this error while making:
[ 30%] Building CXX object modules/highgui/CMakeFiles/opencv_highgui.dir/src/window_gtk.cpp.o
/share/apps/computer/opencv-3.2.0/modules/highgui/src/window_gtk.cpp: In function 'void cvImageWidget_realize(GtkWidget*)':
/share/apps/computer/opencv-3.2.0/modules/highgui/src/window_gtk.cpp:177: error: 'gtk_widget_set_realized' was not declared in this scope
/share/apps/computer/opencv-3.2.0/modules/highgui/src/window_gtk.cpp: In function 'void cvImageWidget_size_allocate(GtkWidget*, GtkAllocation*)':
/share/apps/computer/opencv-3.2.0/modules/highgui/src/window_gtk.cpp:389: error: 'gtk_widget_get_realized' was not declared in this scope
make[2]: *** [modules/highgui/CMakeFiles/opencv_highgui.dir/src/window_gtk.cpp.o] Error 1
make[1]: *** [modules/highgui/CMakeFiles/opencv_highgui.dir/all] Error 2
make: *** [all] Error 2
As I checked, the versions are compatible with the documents.