diff --git a/package/collectd/Config.in b/package/collectd/Config.in
index 683141b120..47bfe95d98 100644
--- a/package/collectd/Config.in
+++ b/package/collectd/Config.in
@@ -526,6 +526,7 @@ config BR2_PACKAGE_COLLECTD_GRAPHITE
 
 config BR2_PACKAGE_COLLECTD_MQTT
 	bool "mqtt"
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4 # mosquitto
 	select BR2_PACKAGE_MOSQUITTO
 	help
 	  Sends metrics to and/or receives metrics from an MQTT broker.
diff --git a/package/domoticz/Config.in b/package/domoticz/Config.in
index f128e6f88c..c6550d2ad0 100644
--- a/package/domoticz/Config.in
+++ b/package/domoticz/Config.in
@@ -1,6 +1,7 @@
 config BR2_PACKAGE_DOMOTICZ
 	bool "domoticz"
 	depends on BR2_USE_MMU # mosquitto
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4 # mosquitto
 	depends on !BR2_STATIC_LIBS # mosquitto
 	depends on BR2_TOOLCHAIN_HAS_THREADS
 	depends on BR2_INSTALL_LIBSTDCPP
@@ -28,6 +29,7 @@ config BR2_PACKAGE_DOMOTICZ
 
 comment "domoticz needs lua >= 5.2 and a toolchain w/ C++, threads, wchar, dynamic library"
 	depends on BR2_USE_MMU
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	depends on !BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_SH
 	depends on !BR2_INSTALL_LIBSTDCPP || !BR2_TOOLCHAIN_HAS_THREADS || \
 		!BR2_USE_WCHAR || BR2_STATIC_LIBS || \
diff --git a/package/mosquitto/Config.in b/package/mosquitto/Config.in
index 50937d0554..1e6418a4de 100644
--- a/package/mosquitto/Config.in
+++ b/package/mosquitto/Config.in
@@ -1,6 +1,7 @@
 config BR2_PACKAGE_MOSQUITTO
 	bool "mosquitto"
 	depends on BR2_USE_MMU # fork()
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	depends on !BR2_STATIC_LIBS # builds .so
 	help
 	  Mosquitto is an open source message broker that implements
@@ -15,4 +16,5 @@ config BR2_PACKAGE_MOSQUITTO
 
 comment "mosquitto needs a toolchain w/ dynamic library"
 	depends on BR2_USE_MMU
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	depends on BR2_STATIC_LIBS