align.el marker fix.

* lisp/align.el (align--set-marker): Add doc-string.
Don't try to move something that is not a marker. 
Eg the first call from align-region passes eol == 0.

Fixes: debbugs:10216

2 files changed, 8 insertions, 1 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index e1fa6c6ec31..413a2947a58 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,8 @@
+2011-12-05  Glenn Morris  <rgm@gnu.org>
+
+        * align.el (align--set-marker): Add doc-string.
+        Don't try to move something that is not a marker.  (Bug#10216)
+
 2011-12-04  Glenn Morris  <rgm@gnu.org>
 
         * calendar/appt.el (appt-add): Rewrite the interactive-spec to avoid
diff --git a/lisp/align.el b/lisp/align.el
index 0d9f351b9da..a386b7a82ba 100644
--- a/lisp/align.el
+++ b/lisp/align.el
@@ -1247,7 +1247,9 @@ have been aligned.  No changes will be made to the buffer."
         (setq areas (cdr areas))))))
 
 (defmacro align--set-marker (marker-var pos &optional type)
-  `(if ,marker-var
+  "If MARKER-VAR is a marker, move it to position POS.
+Otherwise, create a new marker at position POS, with type TYPE."
+  `(if (markerp ,marker-var)
        (move-marker ,marker-var ,pos)
      (setq ,marker-var (copy-marker ,pos ,type))))