updated for version 7.4.643

Problem:    Using the default file format for Mac files. (Issue 77)
Solution:   Reset the try_mac counter in the right place. (Oswald)

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    643,
 /**/
     642,
 /**/