[PATCH] include-next, warnings: support older autoconf

[Eric Blake]

Older autoconf did not know how to peer through quoting of the
m4 macro created by AS_VAR_PUSHDEF; while newer autoconf has
been patched to allow typical autoconf quoting rules to still
apply, compatibility with autoconf 2.59 requires the unquoted
use of the macro name for all uses prior to AS_VAR_POPDEF.

absolute-header.m4 and warn-on-use.m4 already got this right.

* m4/include_next.m4 (gl_NEXT_HEADERS_INTERNAL): Use
AS_VAR_PUSHDEF in a way that works with older autoconf.
* m4/warnings.m4 (gl_WARN_ADD): Likewise.
Reported by Daniel P. Berrange.

Signed-off-by: Eric Blake <address@hidden>
---
 ChangeLog          |    8 ++++++++
 m4/include_next.m4 |   12 ++++++------
 m4/warnings.m4     |   10 +++++-----
 3 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index cbf42ee..2752af0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2011-07-26  Eric Blake  <address@hidden>
+
+       include-next, warnings: support older autoconf
+       * m4/include_next.m4 (gl_NEXT_HEADERS_INTERNAL): Use
+       AS_VAR_PUSHDEF in a way that works with older autoconf.
+       * m4/warnings.m4 (gl_WARN_ADD): Likewise.
+       Reported by Daniel P. Berrange.
+
 2011-07-25  Bruno Haible  <address@hidden>

        fseek, ftell: Fix doc.
diff --git a/m4/include_next.m4 b/m4/include_next.m4
index b3c7849..da313b3 100644
--- a/m4/include_next.m4
+++ b/m4/include_next.m4
@@ -1,4 +1,4 @@
-# include_next.m4 serial 18
+# include_next.m4 serial 19
 dnl Copyright (C) 2006-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -179,7 +179,7 @@ AC_DEFUN([gl_NEXT_HEADERS_INTERNAL],
     [AS_VAR_PUSHDEF([gl_next_header],
                     [gl_cv_next_]m4_defn([gl_HEADER_NAME]))
      if test $gl_cv_have_include_next = yes; then
-       AS_VAR_SET([gl_next_header], ['<'gl_HEADER_NAME'>'])
+       AS_VAR_SET(gl_next_header, ['<'gl_HEADER_NAME'>'])
      else
        AC_CACHE_CHECK(
          [absolute name of <]m4_defn([gl_HEADER_NAME])[>],
@@ -208,7 +208,7 @@ AC_DEFUN([gl_NEXT_HEADERS_INTERNAL],
                dnl eval is necessary to expand gl_absname_cpp.
                dnl Ultrix and Pyramid sh refuse to redirect output of eval,
                dnl so use subshell.
-               AS_VAR_SET([gl_next_header],
+               AS_VAR_SET(gl_next_header,
                  ['"'`(eval "$gl_absname_cpp conftest.$ac_ext") 
2>&AS_MESSAGE_LOG_FD |
                   sed -n '\#/]m4_defn([gl_HEADER_NAME])[#{
                     s#.*"\(.*/]m4_defn([gl_HEADER_NAME])[\)".*#\1#
@@ -218,20 +218,20 @@ AC_DEFUN([gl_NEXT_HEADERS_INTERNAL],
                   }'`'"'])
           m4_if([$2], [check],
             [else
-               AS_VAR_SET([gl_next_header], ['<'gl_HEADER_NAME'>'])
+               AS_VAR_SET(gl_next_header, ['<'gl_HEADER_NAME'>'])
              fi
             ])
          ])
      fi
      AC_SUBST(
        AS_TR_CPP([NEXT_]m4_defn([gl_HEADER_NAME])),
-       [AS_VAR_GET([gl_next_header])])
+       [AS_VAR_GET(gl_next_header)])
      if test $gl_cv_have_include_next = yes || test $gl_cv_have_include_next = 
buggy; then
        # INCLUDE_NEXT_AS_FIRST_DIRECTIVE='include_next'
        gl_next_as_first_directive='<'gl_HEADER_NAME'>'
      else
        # INCLUDE_NEXT_AS_FIRST_DIRECTIVE='include'
-       gl_next_as_first_directive=AS_VAR_GET([gl_next_header])
+       gl_next_as_first_directive=AS_VAR_GET(gl_next_header)
      fi
      AC_SUBST(
        AS_TR_CPP([NEXT_AS_FIRST_DIRECTIVE_]m4_defn([gl_HEADER_NAME])),
diff --git a/m4/warnings.m4 b/m4/warnings.m4
index b2d1a29..877c5a7 100644
--- a/m4/warnings.m4
+++ b/m4/warnings.m4
@@ -1,4 +1,4 @@
-# warnings.m4 serial 3
+# warnings.m4 serial 4
 dnl Copyright (C) 2008-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -20,16 +20,16 @@ m4_ifdef([AS_VAR_APPEND],
 # gl_WARN_ADD([-Wparentheses]).
 AC_DEFUN([gl_WARN_ADD],
 [AS_VAR_PUSHDEF([gl_Warn], [gl_cv_warn_$1])dnl
-AC_CACHE_CHECK([whether compiler handles $1], [gl_Warn], [
+AC_CACHE_CHECK([whether compiler handles $1], m4_defn([gl_Warn]), [
   gl_save_CPPFLAGS="$CPPFLAGS"
   CPPFLAGS="${CPPFLAGS} $1"
   AC_PREPROC_IFELSE([AC_LANG_PROGRAM([])],
-                    [AS_VAR_SET([gl_Warn], [yes])],
-                    [AS_VAR_SET([gl_Warn], [no])])
+                    [AS_VAR_SET(gl_Warn, [yes])],
+                    [AS_VAR_SET(gl_Warn, [no])])
   CPPFLAGS="$gl_save_CPPFLAGS"
 ])
 AS_VAR_PUSHDEF([gl_Flags], m4_if([$2], [], [[WARN_CFLAGS]], [[$2]]))dnl
-AS_VAR_IF([gl_Warn], [yes], [gl_AS_VAR_APPEND([gl_Flags], [" $1"])])
+AS_VAR_IF(gl_Warn, [yes], [gl_AS_VAR_APPEND([gl_Flags], [" $1"])])
 AS_VAR_POPDEF([gl_Flags])dnl
 AS_VAR_POPDEF([gl_Warn])dnl
 m4_ifval([$2], [AS_LITERAL_IF([$2], [AC_SUBST([$2])], [])])dnl
-- 
1.7.4.4