Merge branch 'maint'

lisp/org-agenda.el

@@ -7003,7 +7003,8 @@ The optional argument TYPE tells the agenda type."
 				  "\\([ \t]*\\[[a-zA-Z0-9]\\]\\)? *") tb)
 	(setq tb (substring tb (match-end 0))))
       (setq tb (downcase tb)))
-    (cond ((not ta) +1)
+    (cond ((not (or ta tb)) nil)
+	  ((not ta) +1)
 	  ((not tb) -1)
 	  ((string-lessp ta tb) -1)
 	  ((string-lessp tb ta) +1))))
@@ -7012,7 +7013,8 @@ The optional argument TYPE tells the agenda type."
   "Compare the string values of the first tags of A and B."
   (let ((ta (car (last (get-text-property 1 'tags a))))
 	(tb (car (last (get-text-property 1 'tags b)))))
-    (cond ((not ta) +1)
+    (cond ((not (or ta tb)) nil)
+	  ((not ta) +1)
 	  ((not tb) -1)
 	  ((string-lessp ta tb) -1)
 	  ((string-lessp tb ta) +1))))