diff --git a/runtime/doc/quickfix.txt b/runtime/doc/quickfix.txt
index 96ba382..cbfd791 100644
--- a/runtime/doc/quickfix.txt
+++ b/runtime/doc/quickfix.txt
@@ -1422,6 +1422,7 @@
 Basic items
 
 	%f		file name (finds a string)
+	%b		buffer number (finds a number)
 	%o		module name (finds a string)
 	%l		line number (finds a number)
 	%e		end line number (finds a number)
@@ -1461,6 +1462,11 @@
 This means that a file name which is a single alphabetical letter will not be
 detected.
 
+The "%b" conversion is used to parse a buffer number.  This is useful for
+referring to lines in a scratch buffer or a buffer with no name.  If a buffer
+with the matching number doesn't exist, then that line is used as a non-error
+line.
+
 The "%p" conversion is normally followed by a "^".  It's used for compilers
 that output a line like: >
 	    ^
diff --git a/runtime/doc/todo.txt b/runtime/doc/todo.txt
index 4dc8db4..3a7b6ef 100644
--- a/runtime/doc/todo.txt
+++ b/runtime/doc/todo.txt
@@ -5945,8 +5945,6 @@
 7   Instead of filtering errors with a shell script it should be possible to
     do this with Vim script.  A function that filters the raw text that comes
     from the 'makeprg'?
--   Add %b to 'errorformat': buffer number. (Yegappan Lakshmanan / Suresh
-    Govindachar)
 7   Allow a window not to have a statusline.  Makes it possible to use a
     window as a buffer-tab selection.
 8   Allow non-active windows to have a different statusline. (Yakov Lerner)