From ed4dc717696ddc791363f2301fb4a142d4ef4633 Mon Sep 17 00:00:00 2001
From: James Zern <jzern@google.com>
Date: Tue, 2 Apr 2013 18:45:02 -0700
Subject: [PATCH] configure.ac: add AM_PROG_AR for automake >= 1.12

fixes:
automake-1.12/am/ltlibrary.am: warning: 'libwebp.la': linking libtool libraries using a non-POSIX
automake-1.12/am/ltlibrary.am: archiver requires 'AM_PROG_AR' in 'configure.ac'

Change-Id: I223f93e5f075aaf23cfefceef55e2ab8eeb34ccd
---
 configure.ac | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/configure.ac b/configure.ac
index 3b344f0e..df0560a0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3,6 +3,11 @@ AC_INIT([libwebp], [0.3.0],
         [http://developers.google.com/speed/webp])
 AC_CANONICAL_TARGET
 AM_INIT_AUTOMAKE([-Wall foreign subdir-objects])
+
+dnl === automake >= 1.12 requires this for 'unusual archivers' support.
+dnl === it must occur before LT_INIT (AC_PROG_LIBTOOL).
+m4_ifdef([AM_PROG_AR], [AM_PROG_AR])
+
 AC_PROG_LIBTOOL
 AM_PROG_CC_C_O