configure.ac: add an autoconf version prerequisite

ax_pthread.m4 uses AS_CASE() which was added in 2.60

Change-Id: Ifafe2271a8814c734a20d24048e9b24925e13077
This commit is contained in:
James Zern 2014-07-01 20:02:58 -07:00
parent 6ee7160dd2
commit 34b02f8cb0

View File

@ -2,6 +2,7 @@ AC_INIT([libwebp], [0.4.0],
[http://code.google.com/p/webp/issues],,
[http://developers.google.com/speed/webp])
AC_CANONICAL_TARGET
AC_PREREQ([2.60])
AM_INIT_AUTOMAKE([-Wall foreign subdir-objects])
dnl === automake >= 1.12 requires this for 'unusual archivers' support.