Fix broken customization in Flymake.

* lisp/progmodes/flymake.el (flymake-get-real-file-name-function):
Fix broken customization.  (Bug#15184)

doc/lispref/nonascii.texi

@@ -248,6 +248,7 @@ unibyte string, it is returned unchanged.  Use this function for
 characters.
 @end defun
 
+@c FIXME: Should `@var{character}' be `@var{byte}'?
 @defun byte-to-string byte
 @cindex byte to string
 This function returns a unibyte string containing a single byte of
@@ -401,6 +402,8 @@ specifies how the character behaves and how it should be handled
 during text processing and display.  Thus, character properties are an
 important part of specifying the character's semantics.
 
+@c FIXME: Use the latest URI of this chapter?
+@c http://www.unicode.org/versions/latest/ch04.pdf
   On the whole, Emacs follows the Unicode Standard in its implementation
 of character properties.  In particular, Emacs supports the
 @uref{http://www.unicode.org/reports/tr23/, Unicode Character Property

lisp/ChangeLog

@@ -1,3 +1,8 @@
+2013-08-25  Xue Fuqiao  <xfq.free@gmail.com>
+
+	* progmodes/flymake.el (flymake-get-real-file-name-function):
+	Fix broken customization.  (Bug#15184)
+
 2013-08-25  Alan Mackenzie  <acm@muc.de>
 
 	Improve indentation of bracelists defined by macros (without "=").

lisp/progmodes/flymake.el

@@ -353,7 +353,7 @@ Return nil if we cannot, non-nil if we can."
       'flymake-simple-cleanup))
 
 (defun flymake-get-real-file-name-function (file-name)
-  (or (nth 4 (flymake-get-file-name-mode-and-masks file-name))
+  (or (nth 2 (flymake-get-file-name-mode-and-masks file-name))
       'flymake-get-real-file-name))
 
 (defvar flymake-find-buildfile-cache (flymake-makehash 'equal))