diff --git a/extensions/CCArmature/external_tool/sigslot.h b/extensions/CCArmature/external_tool/sigslot.h
index 23c4e5bb4c..3513a6f857 100644
--- a/extensions/CCArmature/external_tool/sigslot.h
+++ b/extensions/CCArmature/external_tool/sigslot.h
@@ -311,6 +311,7 @@ namespace sigslot {
 	class _connection_base1
 	{
 	public:
+		virtual ~_connection_base1() {};
 		virtual has_slots<mt_policy>* getdest() const = 0;
 		virtual void emit(arg1_type) = 0;
 		virtual _connection_base1<arg1_type, mt_policy>* clone() = 0;
@@ -321,6 +322,7 @@ namespace sigslot {
 	class _connection_base2
 	{
 	public:
+		virtual ~_connection_base2() {};
 		virtual has_slots<mt_policy>* getdest() const = 0;
 		virtual void emit(arg1_type, arg2_type) = 0;
 		virtual _connection_base2<arg1_type, arg2_type, mt_policy>* clone() = 0;
@@ -331,6 +333,7 @@ namespace sigslot {
 	class _connection_base3
 	{
 	public:
+		virtual ~_connection_base3() {};
 		virtual has_slots<mt_policy>* getdest() const = 0;
 		virtual void emit(arg1_type, arg2_type, arg3_type) = 0;
 		virtual _connection_base3<arg1_type, arg2_type, arg3_type, mt_policy>* clone() = 0;
@@ -341,6 +344,7 @@ namespace sigslot {
 	class _connection_base4
 	{
 	public:
+		virtual ~_connection_base4() {};
 		virtual has_slots<mt_policy>* getdest() const = 0;
 		virtual void emit(arg1_type, arg2_type, arg3_type, arg4_type) = 0;
 		virtual _connection_base4<arg1_type, arg2_type, arg3_type, arg4_type, mt_policy>* clone() = 0;
@@ -352,6 +356,7 @@ namespace sigslot {
 	class _connection_base5
 	{
 	public:
+		virtual ~_connection_base5() {};
 		virtual has_slots<mt_policy>* getdest() const = 0;
 		virtual void emit(arg1_type, arg2_type, arg3_type, arg4_type,
                           arg5_type) = 0;
@@ -366,6 +371,7 @@ namespace sigslot {
 	class _connection_base6
 	{
 	public:
+		virtual ~_connection_base6() {};
 		virtual has_slots<mt_policy>* getdest() const = 0;
 		virtual void emit(arg1_type, arg2_type, arg3_type, arg4_type, arg5_type,
                           arg6_type) = 0;