From 12525d4cd7c38937696adb827d5291669524eb2b Mon Sep 17 00:00:00 2001
From: Jan Beich <jbeich@FreeBSD.org>
Date: Wed, 1 Jan 2020 11:02:37 +0000
Subject: [PATCH] autotools: avoid -ldl if not required or not supported

ld: error: unable to find library -ldl
---
 configure.ac   |  5 +++++
 va/Makefile.am | 10 +++++-----
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/configure.ac b/configure.ac
index acb4c79..a62f4fd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -209,6 +209,11 @@ if test "$ac_cv_have_gnuc_visibility_attribute" = "yes"; then
               [Defined to 1 if GCC visibility attribute is supported])
 fi
 
+# Check for -ldl (often not required)
+AC_SEARCH_LIBS([dlopen], [dl], [], [
+  AC_MSG_ERROR([unable to find the dlopen() function])
+])
+
 # Check for -fstack-protector
 ssp_cc=yes
 if test "X$CC-cc" != "X"; then
diff --git a/va/Makefile.am b/va/Makefile.am
index 6742177..6155895 100644
--- a/va/Makefile.am
+++ b/va/Makefile.am
@@ -92,7 +92,7 @@ libva_la_SOURCES		= $(libva_source_c)
 libva_la_CFLAGS			= $(libva_cflags)
 libva_la_LDFLAGS		= $(libva_ldflags)
 libva_la_DEPENDENCIES		= libva.syms
-libva_la_LIBADD			= $(LIBVA_LIBS) -ldl
+libva_la_LIBADD			= $(LIBVA_LIBS)
 
 if USE_DRM
 SUBDIRS				+= drm
@@ -102,7 +102,7 @@ libva_drm_la_CFLAGS		= $(libva_cflags)
 libva_drm_la_LDFLAGS		= $(LDADD)
 libva_drm_la_DEPENDENCIES	= libva.la drm/libva_drm.la
 libva_drm_la_LIBADD		= libva.la drm/libva_drm.la \
-	$(LIBVA_LIBS) $(DRM_LIBS) -ldl
+	$(LIBVA_LIBS) $(DRM_LIBS)
 endif
 
 if USE_X11
@@ -114,7 +114,7 @@ libva_x11_la_CFLAGS		= $(libva_cflags)
 libva_x11_la_LDFLAGS		= $(LDADD)
 libva_x11_la_DEPENDENCIES	= libva.la x11/libva_x11.la
 libva_x11_la_LIBADD		= libva.la x11/libva_x11.la \
-	$(LIBVA_LIBS) $(X11_LIBS) $(XEXT_LIBS) $(XFIXES_LIBS) $(DRM_LIBS) -ldl
+	$(LIBVA_LIBS) $(X11_LIBS) $(XEXT_LIBS) $(XFIXES_LIBS) $(DRM_LIBS)
 endif
 
 if USE_GLX
@@ -125,7 +125,7 @@ libva_glx_la_CFLAGS		= $(libva_cflags)
 libva_glx_la_LDFLAGS		= $(LDADD)
 libva_glx_la_DEPENDENCIES	= libva.la glx/libva_glx.la libva-x11.la
 libva_glx_la_LIBADD		= libva.la glx/libva_glx.la libva-x11.la \
-	$(GLX_LIBS) -ldl
+	$(GLX_LIBS)
 endif
 
 if USE_WAYLAND
@@ -136,7 +136,7 @@ libva_wayland_la_CFLAGS		= $(libva_cflags)
 libva_wayland_la_LDFLAGS	= $(LDADD)
 libva_wayland_la_DEPENDENCIES	= libva.la wayland/libva_wayland.la
 libva_wayland_la_LIBADD		= libva.la wayland/libva_wayland.la \
-	$(WAYLAND_LIBS) $(DRM_LIBS) -ldl
+	$(WAYLAND_LIBS) $(DRM_LIBS)
 endif
 
 DIST_SUBDIRS = x11 glx drm wayland