From e855b2cb3137f4c2531a2ad0f2b18eef085787fe Mon Sep 17 00:00:00 2001
From: SASANO Takayoshi <uaa@uaa.org.uk>
Date: Tue, 3 Jan 2023 11:13:19 +0900
Subject: [PATCH] avoid libdl detecion on *BSD

  NetBSD and OpenBSD has no libdl
  FreeBSD and DragonFlyBSD has libdl but dummy

  These OSes are no need to use -ldl to use dlopen()
---
 configure.ac | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/configure.ac b/configure.ac
index 3989a743..aaf869df 100644
--- a/configure.ac
+++ b/configure.ac
@@ -255,11 +255,19 @@ AC_ARG_WITH(libdl,
   [ have_libdl="$withval" ], [ have_libdl="yes" ])
 HAVE_LIBDL=
 if test "$have_libdl" = "yes"; then
-  AC_CHECK_LIB([dl], [dlsym], [HAVE_LIBDL="yes"])
-  if test "$HAVE_LIBDL" = "yes" ; then
-    ALSA_DEPLIBS="$ALSA_DEPLIBS -ldl"
+  case $host_os in
+  netbsd* | freebsd* | dragonfly* | openbsd*)
+    HAVE_LIBDL=yes
     AC_DEFINE([HAVE_LIBDL], 1, [Have libdl])
-  fi
+    ;;
+  *)
+    AC_CHECK_LIB([dl], [dlsym], [HAVE_LIBDL="yes"])
+    if test "$HAVE_LIBDL" = "yes" ; then
+      ALSA_DEPLIBS="$ALSA_DEPLIBS -ldl"
+      AC_DEFINE([HAVE_LIBDL], 1, [Have libdl])
+    fi
+    ;;
+  esac
 else
   AC_MSG_RESULT(no)
 fi