Re: Gnulib needed in AC_CHECK_HEADERS

[Paul Eggert]

Bruno Haible <address@hidden> writes:

> Ok, if you don't think there are negative side effects of the change, I don't
> want to stand in your way. I only mentioned an alternative change that could
> potentially have less negative side effects. But if there are no downsides
> anyway, your change is preferable.

OK, thanks, I installed it.  Here it is again, for reference:

2008-01-08  Paul Eggert  <address@hidden>

        gl_FUNC_ALLOCA no longer defines HAVE_ALLOCA_H unconditionally.
        See 
<http://lists.gnu.org/archive/html/bug-gnulib/2007-12/msg00149.html>.
        * NEWS: announce this.
        * m4/alloca.m4 (gl_FUNC_ALLOCA): Don't define HAVE_ALLOCA_H.

diff --git a/NEWS b/NEWS
index c30b272..b60233f 100644
--- a/NEWS
+++ b/NEWS
@@ -6,6 +6,12 @@ User visible incompatible changes

 Date        Modules         Changes

+2008-01-08  alloca-opt      Now defines HAVE_ALLOCA_H only when the system
+                            supplies an <alloca.h>.  Gnulib-using code is now
+                            expected to include <alloca.h> unconditionally.
+                            Non-gnulib-using code can continue to include
+                            <alloca.h> only if HAVE_ALLOCA_H is defined.
+
 2007-12-24  setenv          The include file is changed from "setenv.h" to
                             <stdlib.h>. Also, the unsetenv function is no
                             longer declared in this module; use the 'unsetenv'
diff --git a/m4/alloca.m4 b/m4/alloca.m4
index eb62e0e..95f54a6 100644
--- a/m4/alloca.m4
+++ b/m4/alloca.m4
@@ -1,5 +1,5 @@
-# alloca.m4 serial 7
-dnl Copyright (C) 2002-2004, 2006 Free Software Foundation, Inc.
+# alloca.m4 serial 8
+dnl Copyright (C) 2002-2004, 2006, 2007 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -39,10 +39,6 @@ AC_DEFUN([gl_FUNC_ALLOCA],
     ALLOCA_H=alloca.h
   fi
   AC_SUBST([ALLOCA_H])
-
-  AC_DEFINE(HAVE_ALLOCA_H, 1,
-    [Define HAVE_ALLOCA_H for backward compatibility with older code
-     that includes <alloca.h> only if HAVE_ALLOCA_H is defined.])
 ])

 # Prerequisites of lib/alloca.c.