configure: fix libtool warning

Recent versions of libtool are now tracing usage of AC_CONFIG_MACRO_DIR
macro and warn heavily when not used in configure script along with
ACLOCAL_AMFLAGS in Makefile.am.  So in order to make libtool happy
while keeping backwards compatibility this is added.

diff --git a/configure.ac b/configure.ac
index d5be61c..730f8ff 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -8,6 +8,7 @@ CARES_OVERRIDE_AUTOCONF
 
 AC_CONFIG_SRCDIR([ares_ipv6.h])
 AM_CONFIG_HEADER([ares_config.h ares_build.h])
+AC_CONFIG_MACRO_DIR([m4])
 AM_MAINTAINER_MODE
 
 CARES_CHECK_OPTION_DEBUG

diff --git a/m4/cares-override.m4 b/m4/cares-override.m4
index b29c960..101ca61 100644 (file)
--- a/m4/cares-override.m4
+++ b/m4/cares-override.m4
@@ -3,7 +3,7 @@
 #***************************************************************************
 
 # File version for 'aclocal' use. Keep it a single number.
-# serial 3
+# serial 4
 
 dnl CARES_OVERRIDE_AUTOCONF
 dnl -------------------------------------------------
@@ -100,3 +100,12 @@ m4_defun([_LT_AC_LIBTOOL_SYS_PATH_SEPARATOR],
 [CARES_CHECK_PATH_SEPARATOR
 m4_define([$0],[])])
 
+dnl Override Autoconf's AC_CONFIG_MACRO_DIR (DIR)
+dnl -------------------------------------------------
+dnl This is an emulation of Autoconf's 2.61 macro.
+dnl This is done to use fixed macro across Autoconf
+dnl versions, and avoid warnings from modern libtool
+dnl which traces usage of this macro.
+
+AC_DEFUN([AC_CONFIG_MACRO_DIR],[:])
+