diff -urN autoconf-2.62/ChangeLog autoconf-2.62_new/ChangeLog

--- autoconf-2.62/ChangeLog	2008-06-24 15:18:34.000000000 +0200

+++ autoconf-2.62_new/ChangeLog	2008-06-24 15:24:35.000000000 +0200

@@ -1,3 +1,14 @@

+2008-06-16  Ralf Wildenhues  <Ralf.Wildenhues@gmx.de>

+

+	Fix '#undef variable /* comment */' transform in config headers.

+	* lib/autoconf/status.m4 (_AC_OUTPUT_HEADERS_PREPARE): For

+	undefined preprocessor macros that are followed by a comment

+	in the header template, do not create nested comments in the

+	output.

+	* tests/torture.at (@%:@define header templates): Extend test.

+	* NEWS: Update.

+	Report by Karsten Hopp <karsten@redhat.com>.

+

 2008-06-05  Eric Blake  <ebb9@byu.net>

 	Fix regression in AT_KEYWORDS([Macro]), from 2007-10-18.

diff -urN autoconf-2.62/lib/autoconf/status.m4 autoconf-2.62_new/lib/autoconf/status.m4

--- autoconf-2.62/lib/autoconf/status.m4	2008-04-06 01:04:48.000000000 +0200

+++ autoconf-2.62_new/lib/autoconf/status.m4	2008-06-24 15:21:54.000000000 +0200

@@ -832,9 +832,9 @@

   }

   split(mac1, mac2, "(") #)

   macro = mac2[1]

+  prefix = substr(line, 1, index(line, defundef) - 1)

   if (D_is_set[macro]) {

     # Preserve the white space surrounding the "#".

-    prefix = substr(line, 1, index(line, defundef) - 1)

     print prefix "define", macro P[macro] D[macro]

     next

   } else {

@@ -842,7 +842,7 @@

     # in the case of _POSIX_SOURCE, which is predefined and required

     # on some systems where configure will not decide to define it.

     if (defundef == "undef") {

-      print "/*", line, "*/"

+      print "/*", prefix defundef, macro, "*/"

       next

     }

   }

diff -urN autoconf-2.62/NEWS autoconf-2.62_new/NEWS

--- autoconf-2.62/NEWS	2008-06-24 15:18:34.000000000 +0200

+++ autoconf-2.62_new/NEWS	2008-06-24 15:25:28.000000000 +0200

@@ -25,6 +25,9 @@

    like '__restrict' if the variant spelling is available, as this is

    more likely to work when mixing C and C++ code.

+** Config header templates `#undef UNDEFINED /* comment */' do not lead to

+   nested comments any more; regression introduced in 2.62.

+

 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must

    be a string of tokens such that "T y;" is a valid member declaration

    in a struct.

diff -urN autoconf-2.62/tests/torture.at autoconf-2.62_new/tests/torture.at

--- autoconf-2.62/tests/torture.at	2008-04-06 01:04:48.000000000 +0200

+++ autoconf-2.62_new/tests/torture.at	2008-06-24 15:23:21.000000000 +0200

@@ -497,6 +497,8 @@

 #define str(define) \

 #define

 #define stringify(arg) str(arg)

+#undef aaa /* with comments */

+#undef not_substed /* with comments */

 ]])

 AT_CHECK_AUTOCONF

@@ -527,6 +529,8 @@

 #define str(define) \

 #define

 #define stringify(arg) str(arg)

+#define aaa AAA

+/* #undef not_substed */

 ]])

 AT_CHECK([cat config.h], 0, expout)