set_up_x_back_buffer  165 src/xfns.c     static void set_up_x_back_buffer (struct frame *f);
set_up_x_back_buffer  872 src/xfns.c             set_up_x_back_buffer (f);
set_up_x_back_buffer 4020 src/xfns.c         set_up_x_back_buffer (f);