1 files changed, 14 insertions, 4 deletions

diff --git a/src/keyboard.c b/src/keyboard.c
index f41ce352cb8..3826d460e3f 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -5507,13 +5507,23 @@ make_lispy_event (event)
                 if (CONSP (down)
                     && INTEGERP (XCAR (down)) && INTEGERP (XCDR (down)))
                   {
-                    xdiff = XFASTINT (event->x) - XFASTINT (XCAR (down));
-                    ydiff = XFASTINT (event->y) - XFASTINT (XCDR (down));
+                    xdiff = XINT (event->x) - XINT (XCAR (down));
+                    ydiff = XINT (event->y) - XINT (XCDR (down));
                   }
 
                 if (xdiff < double_click_fuzz && xdiff > - double_click_fuzz
-                    && ydiff < double_click_fuzz
-                    && ydiff > - double_click_fuzz)
+                    && ydiff < double_click_fuzz && ydiff > - double_click_fuzz
+                  /* Maybe the mouse has moved a lot, caused scrolling, and
+                     eventually ended up at the same screen position (but
+                     not buffer position) in which case it is a drag, not
+                     a click.  */
+                    /* FIXME: OTOH if the buffer position has changed
+                       because of a timer or process filter rather than
+                       because of mouse movement, it should be considered as
+                       a click.  But mouse-drag-region completely ignores
+                       this case and it hasn't caused any real problem, so
+                       it's probably OK to ignore it as well.  */
+                    && EQ (Fcar (Fcdr (start_pos)), Fcar (Fcdr (position))))
                   /* Mouse hasn't moved (much).  */
                   event->modifiers |= click_modifier;
                 else