[PATCH] Add back AH_CHECK_HEADERS.

[Paolo Bonzini]

Here it is.  I tested with this:

        AC_INIT
        AC_CONFIG_HEADER([test.h])
        m4_define([a], [argh])
        m4_define([A], [argh])
        m4_define([HAVE_B_H], [strange])
        AH_CHECK_HEADERS([a.h b.h])

that the output is the same as for Autoconf 2.53.  I don't think the
testcase is worth putting in the testsuite, but I can do that if
you wish.

2009-07-30  Paolo Bonzini  <address@hidden>

        Add back AH_CHECK_HEADERS.
        * lib/autoconf/general.m4 (AH_CHECK_HEADERS): New.
        * NEWS: Create new section.
---
 ChangeLog               |    5 +++++
 NEWS                    |    9 +++++++++
 lib/autoconf/headers.m4 |    6 ++++++
 3 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 1e22e63..c086c57 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,4 +1,9 @@
 2009-07-30  Paolo Bonzini  <address@hidden>
+
+       Add back AH_CHECK_HEADERS.
+       * lib/autoconf/general.m4 (AH_CHECK_HEADERS): New.
+       * NEWS: Create new section.
+
+2009-07-30  Paolo Bonzini  <address@hidden>
            Joel E. Denny  <address@hidden>
 
        Clarify comparison of echo, printf, and AS_ECHO*.
diff --git a/NEWS b/NEWS
index fc5730f..7e8a522 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,14 @@
 GNU Autoconf NEWS - User visible changes.
 
+* Major changes in Autoconf 2.64a (????-??-??) [experimental]
+  Released by ???? ????
+
+** The following undocumented autoconf macros, removed in Autoconf 2.64,
+   have been reinstated:
+   AH_CHECK_HEADERS
+
+   These macros are present only for backwards compatibility purposes.
+
 * Major changes in Autoconf 2.64 (2009-07-26) [stable]
   Released by Eric Blake, based on git versions 2.63b.*.
 
diff --git a/lib/autoconf/headers.m4 b/lib/autoconf/headers.m4
index 21b512c..36c1899 100644
--- a/lib/autoconf/headers.m4
+++ b/lib/autoconf/headers.m4
@@ -253,6 +253,12 @@ m4_define([_AH_CHECK_HEADER],
   [Define to 1 if you have the <$1> header file.])])
 
 
+# AH_CHECK_HEADERS(HEADER-FILE...)
+# --------------------------------
+m4_define([AH_CHECK_HEADERS],
+[m4_foreach_w([AC_Header], [$1], [_AH_CHECK_HEADER(m4_defn([AC_Header]))])])
+
+
 # AC_CHECK_HEADERS(HEADER-FILE...,
 #                 [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND],
 #                 [INCLUDES])