diff --git a/package/gstreamer1/gst1-plugins-bad/Config.in b/package/gstreamer1/gst1-plugins-bad/Config.in
index 6e7d21d126..68fed23de4 100644
--- a/package/gstreamer1/gst1-plugins-bad/Config.in
+++ b/package/gstreamer1/gst1-plugins-bad/Config.in
@@ -671,6 +671,7 @@ config BR2_PACKAGE_GST1_PLUGINS_BAD_PLUGIN_X265
 	bool "x265"
 	depends on BR2_INSTALL_LIBSTDCPP
 	depends on !BR2_STATIC_LIBS
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4 # x265
 	select BR2_PACKAGE_X265
 	help
 	  x265 encoding plugin
diff --git a/package/x265/Config.in b/package/x265/Config.in
index f268e65841..1d6eda2049 100644
--- a/package/x265/Config.in
+++ b/package/x265/Config.in
@@ -3,6 +3,7 @@ config BR2_PACKAGE_X265
 	depends on BR2_INSTALL_LIBSTDCPP
 	depends on BR2_TOOLCHAIN_HAS_THREADS
 	depends on !BR2_STATIC_LIBS # dlfcn
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	help
 	  x265 is an open source free software and library for encoding video
 	  using the High Efficiency Video Coding (HEVC/H.265) standard. x265 is
@@ -24,3 +25,4 @@ endif
 comment "x265 needs a toolchain w/ C++, threads, dynamic library"
 	depends on !BR2_INSTALL_LIBSTDCPP || BR2_STATIC_LIBS || \
 		!BR2_TOOLCHAIN_HAS_THREADS
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4