From cdd5865a6a31a593b8d33ee338638ebe3bed6391 Mon Sep 17 00:00:00 2001
From: Beniamino Galvani <bgalvani@redhat.com>
Date: Fri, 29 Mar 2019 09:13:59 +0100
Subject: [PATCH] build: fix searching dlopen in configure

The 4th argument of AC_SEARCH_LIBS is a list of additional libraries,
not the name of the variable to hold the result which is always
ac_cv_search_$function. Also, we should ignore the result when it is
"none required".

Fixes: 1f2eeb85d80d ('build: rename $(LIBDL) to $(DL_LIBS) and modify detection')
---
 configure.ac | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 334d9272d..fc09bd461 100644
--- a/configure.ac
+++ b/configure.ac
@@ -240,8 +240,9 @@ AM_CONDITIONAL(WITH_IWD, test x"${ac_with_iwd}" = x"yes")
 dnl
 dnl Checks for libdl - on certain platforms its part of libc
 dnl
-AC_SEARCH_LIBS([dlopen], [dl dld], [], [ac_cv_search_dlopen=])
-AC_SUBST([DL_LIBS], "$ac_cv_search_dlopen")
+AC_SEARCH_LIBS([dlopen], [dl dld],
+	[test "$ac_cv_search_dlopen" = "none required" || AC_SUBST([DL_LIBS], "$ac_cv_search_dlopen"]),
+	[])
 
 PKG_CHECK_MODULES(GLIB, [gio-unix-2.0 >= 2.37.6 gmodule-2.0],
                   [AC_SUBST(LOG_DRIVER, '$(top_srcdir)/build-aux/tap-driver.sh')
-- 
2.20.1