4 files changed, 8 insertions, 0 deletions

diff --git a/include/opkele/consumer.h b/include/opkele/consumer.h
index b9d1e54..50ff692 100644
--- a/include/opkele/consumer.h
+++ b/include/opkele/consumer.h
@@ -19,12 +19,14 @@ namespace opkele {
      * libopkele in multithreaded environment you should call curl_global_init
      * yourself before spawning any threads.
      */
     class consumer_t {
         public:
 
+            virtual ~consumer_t() { }
+
             /**
              * store association. The function should be overridden in the real
              * implementation to provide persistent associations store.
              * @param server the OpenID server
              * @param handle association handle
              * @param secret the secret associated with the server and handle
diff --git a/include/opkele/extension.h b/include/opkele/extension.h
index ea0c74c..513672f 100644
--- a/include/opkele/extension.h
+++ b/include/opkele/extension.h
@@ -12,12 +12,14 @@ namespace opkele {
 
     /**
      * OpenID extension hooks base class
      */
     class extension_t {
         public:
+
+            virtual ~extension_t() { }
             /**
              * hook called by consumer before submitting data to OpenID server.
              * It is supposed to manipulate parameters list.
              * @param p parameters about to be submitted to server
              * @param identity identity being verified. It may differ from the
              * one available in parameters list in case of delegation
diff --git a/include/opkele/server.h b/include/opkele/server.h
index e7e5bb3..dd7fc41 100644
--- a/include/opkele/server.h
+++ b/include/opkele/server.h
@@ -14,12 +14,14 @@ namespace opkele {
     /**
      * implementation of basic server functionality
      */
     class server_t {
         public:
 
+            virtual ~server_t() { }
+
             /**
              * allocate the new association. The function should be overridden
              * in the real implementation to provide persistent assocations
              * store.
              * @param mode the mode of request being processed to base the
              * statelessness of the association upon
diff --git a/include/opkele/types.h b/include/opkele/types.h
index 8f4bf73..f732a1e 100644
--- a/include/opkele/types.h
+++ b/include/opkele/types.h
@@ -62,12 +62,14 @@ namespace opkele {
     /**
      * Interface to the association.
      */
     class association_t {
         public:
 
+            virtual ~association_t() { }
+
             /**
              * retrieve the server with which association was established.
              * @return server name
              */
             virtual string server() const = 0;
             /**