patch 7.4.1084
Problem:    Using "." to repeat CTRL-A in Visual mode increments the wrong
            numbers.
Solution:   Append right size to the redo buffer. (Ozaki Kiichi)
diff --git a/src/normal.c b/src/normal.c
index 640c060..d513f75 100644
--- a/src/normal.c
+++ b/src/normal.c
@@ -3632,7 +3632,7 @@
 	else if (curbuf->b_visual.vi_end.col > curbuf->b_visual.vi_start.col)
 	{
 	    AppendNumberToRedobuff(curbuf->b_visual.vi_end.col
-					 - curbuf->b_visual.vi_start.col - 1);
+					     - curbuf->b_visual.vi_start.col);
 	    AppendCharToRedobuff(' ');
 	}
     }