diff --git a/upnp/inc/ActionComplete.h b/upnp/inc/ActionComplete.h
index f545b5b..13af8f4 100644
--- a/upnp/inc/ActionComplete.h
+++ b/upnp/inc/ActionComplete.h
@@ -9,7 +9,7 @@ extern "C" {
 #endif /* __cplusplus */
 
 
-typedef struct {} UpnpActionComplete;
+typedef struct s_UpnpActionComplete UpnpActionComplete;
 
 
 #include "UpnpString.h"
diff --git a/upnp/inc/ActionRequest.h b/upnp/inc/ActionRequest.h
index 3c18a21..39f5290 100644
--- a/upnp/inc/ActionRequest.h
+++ b/upnp/inc/ActionRequest.h
@@ -10,7 +10,7 @@ extern "C" {
 
 
 /** Returned as part of a \b UPNP_CONTROL_ACTION_COMPLETE callback.  */
-typedef struct {} UpnpActionRequest;
+typedef struct s_UpnpActionRequest UpnpActionRequest;
 
 
 #include "ixml.h"       // for IXML_Document
diff --git a/upnp/inc/Discovery.h b/upnp/inc/Discovery.h
index 50947d2..ed96007 100644
--- a/upnp/inc/Discovery.h
+++ b/upnp/inc/Discovery.h
@@ -10,7 +10,7 @@ extern "C" {
 
 
 /** Returned in a \b UPNP_DISCOVERY_RESULT callback. */
-typedef struct {} UpnpDiscovery;
+typedef struct s_UpnpDiscovery UpnpDiscovery;
 
 
 #include "UpnpString.h"
diff --git a/upnp/inc/Event.h b/upnp/inc/Event.h
index 6d9a1b2..f573b34 100644
--- a/upnp/inc/Event.h
+++ b/upnp/inc/Event.h
@@ -10,7 +10,7 @@ extern "C" {
 
 
 /** Returned along with a \b UPNP_EVENT_RECEIVED callback.  */
-typedef struct {} UpnpEvent;
+typedef struct s_UpnpEvent UpnpEvent;
 
 
 #include "ixml.h"       // for IXML_Document
diff --git a/upnp/inc/EventSubscribe.h b/upnp/inc/EventSubscribe.h
index 4615099..a7c2bff 100644
--- a/upnp/inc/EventSubscribe.h
+++ b/upnp/inc/EventSubscribe.h
@@ -11,7 +11,7 @@ extern "C" {
 
 /** Returned along with a \b UPNP_EVENT_SUBSCRIBE_COMPLETE or
  * \b UPNP_EVENT_UNSUBSCRIBE_COMPLETE callback.  */
-typedef struct {} UpnpEventSubscribe;
+typedef struct s_UpnpEventSubscribe UpnpEventSubscribe;
 
 
 #include "UpnpString.h"
diff --git a/upnp/inc/FileInfo.h b/upnp/inc/FileInfo.h
index 35bdfc8..3da7549 100644
--- a/upnp/inc/FileInfo.h
+++ b/upnp/inc/FileInfo.h
@@ -10,7 +10,7 @@ extern "C" {
 
 
 /** Detailed description of this class should go here */
-typedef struct {} UpnpFileInfo;
+typedef struct s_UpnpFileInfo UpnpFileInfo;
 
 
 #include "ixml.h"       // for DOMString
diff --git a/upnp/inc/StateVarComplete.h b/upnp/inc/StateVarComplete.h
index 05a30c5..7d91687 100644
--- a/upnp/inc/StateVarComplete.h
+++ b/upnp/inc/StateVarComplete.h
@@ -11,7 +11,7 @@ extern "C" {
 
 /** Represents the reply for the current value of a state variable in an
     asynchronous call. */
-typedef struct {} UpnpStateVarComplete;
+typedef struct s_UpnpStateVarComplete UpnpStateVarComplete;
 
 
 #include "UpnpString.h"
diff --git a/upnp/inc/StateVarRequest.h b/upnp/inc/StateVarRequest.h
index 4abc308..3532aa1 100644
--- a/upnp/inc/StateVarRequest.h
+++ b/upnp/inc/StateVarRequest.h
@@ -11,7 +11,7 @@ extern "C" {
 
 /** Represents the request for current value of a state variable in a service
  *  state table.  */
-typedef struct {} UpnpStateVarRequest;
+typedef struct s_UpnpStateVarRequest UpnpStateVarRequest;
 
 
 #include "UpnpString.h"
diff --git a/upnp/inc/SubscriptionRequest.h b/upnp/inc/SubscriptionRequest.h
index 502db9f..e23fd2f 100644
--- a/upnp/inc/SubscriptionRequest.h
+++ b/upnp/inc/SubscriptionRequest.h
@@ -10,7 +10,7 @@ extern "C" {
 
 
 /** Returned along with a \b UPNP_EVENT_SUBSCRIPTION_REQUEST callback. */
-typedef struct {} UpnpSubscriptionRequest;
+typedef struct s_UpnpSubscriptionRequest UpnpSubscriptionRequest;
 
 
 #include "UpnpString.h"
diff --git a/upnp/inc/UpnpString.h b/upnp/inc/UpnpString.h
index 06c31df..2324f6e 100644
--- a/upnp/inc/UpnpString.h
+++ b/upnp/inc/UpnpString.h
@@ -29,7 +29,7 @@ extern "C" {
 /*!
  * \brief Type of the string objects inside libupnp.
  */
-typedef struct {} UpnpString;
+typedef struct s_UpnpString UpnpString;
 
 
 /*!
diff --git a/upnp/src/inc/client_table.h b/upnp/src/inc/client_table.h
index bdf9533..df388f4 100644
--- a/upnp/src/inc/client_table.h
+++ b/upnp/src/inc/client_table.h
@@ -58,7 +58,7 @@ extern TimerThread gTimerThread;
 #ifdef INCLUDE_CLIENT_APIS
 
 
-typedef struct {} ClientSubscription;
+typedef struct s_ClientSubscription ClientSubscription;
 
 
 /** Constructor */
diff --git a/upnp/src/ssdp/ssdp_ResultData.h b/upnp/src/ssdp/ssdp_ResultData.h
index e318d87..65fedb9 100644
--- a/upnp/src/ssdp/ssdp_ResultData.h
+++ b/upnp/src/ssdp/ssdp_ResultData.h
@@ -5,7 +5,7 @@
 
 
 /** Structure to contain Discovery response */
-typedef struct {} SSDPResultData;
+typedef struct s_SSDPResultData SSDPResultData;
 
 
 #include "Discovery.h" /* for UpnpDiscovery */