From 864316403192a3e93a2b1f37de479437964eb7f3 Mon Sep 17 00:00:00 2001
From: Changqing Li <changqing.li@windriver.com>
Date: Thu, 22 Aug 2019 10:45:46 +0800
Subject: [PATCH] Fix libtool detection

Use LT_INIT instead of the deprecated AC_PROG_LIBTOOL to detect libtool, so it
can work with our libtoolize and libtool.

Simplify the detection of ltdl. It will find the ltdl from the sysroot; the
switch --with-system-libltdl is no longer needed. The code is copied from
pulseaudio configure.ac, together with the comment paragraph.

Upstream-Status: Inappropriate [embedded specific]

Signed-off-by: Jesse Zhang <sen.zhang@windriver.com>
Signed-off-by: Jackie Huang <jackie.huang@windriver.com>
Signed-off-by: Changqing Li <changqing.li@windriver.com>
---
 configure.ac | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/configure.ac b/configure.ac
index 6f29206646..c0d6ea99ca 100644
--- a/configure.ac
+++ b/configure.ac
@@ -319,6 +319,42 @@ dnl #  See if we have Git.
 dnl #
 AC_CHECK_PROG(GIT, git, yes, no)
 
+#### libtool stuff ####
+
+dnl set this shit so it doesn't force CFLAGS...
+LTCFLAGS=" "
+
+LT_PREREQ(2.2)
+LT_INIT([dlopen disable-static])
+
+dnl Unfortunately, even up to libtool 2.2.6a there is no way to know
+dnl exactly which version of libltdl is present in the system, so we
+dnl just assume that it's a working version as long as we have the
+dnl library and the header files.
+dnl
+dnl As an extra safety device, check for lt_dladvise_init() which is
+dnl only implemented in libtool 2.x, and refine as we go if we have
+dnl refined requirements.
+dnl
+dnl Check the header files first since the system may have a
+dnl libltdl.so for runtime, but no headers, and we want to bail out as
+dnl soon as possible.
+dnl
+dnl We don't need any special variable for this though, since the user
+dnl can give the proper place to find libltdl through the standard
+dnl variables like LDFLAGS and CPPFLAGS.
+
+AC_CHECK_HEADER([ltdl.h],
+    [AC_CHECK_LIB([ltdl], [lt_dladvise_init], [LIBLTDL=-lltdl], [LIBLTDL=])],
+    [LIBLTDL=])
+
+AS_IF([test "x$LIBLTDL" = "x"],
+    [AC_MSG_ERROR([Unable to find libltdl version 2. Makes sure you have libtool 2.2 or later installed.])])
+AC_SUBST([LIBLTDL])
+LTDL_SUBDIRS=
+INCLTDL=-DWITH_SYSTEM_LTDL
+AC_SUBST(LTDL_SUBDIRS)
+
 dnl Put this in later, when all distributed modules use autoconf.
 dnl AC_ARG_WITH(disablemodulefoo,
 dnl [  --without-rlm_foo         Disables module compilation.  Module list:]
-- 
2.25.1

