diff --git a/cpp/include/Ice/ProxyFunctions.h b/cpp/include/Ice/ProxyFunctions.h
index 459442f79b0..b3f69dbb7e5 100644
--- a/cpp/include/Ice/ProxyFunctions.h
+++ b/cpp/include/Ice/ProxyFunctions.h
@@ -15,11 +15,13 @@ namespace Ice
     /**
      * Verifies that a proxy received from the client is not null, and throws a MarshalException if it is.
      * @param prx The proxy to check.
+     * @param file The source file name.
+     * @param line The source line number.
      * @param current The Current object for the invocation.
      * @throw MarshalException If the proxy is null.
      * */
     template<typename Prx, std::enable_if_t<std::is_base_of<ObjectPrx, Prx>::value, bool> = true>
-    void checkNotNull(std::optional<Prx> prx, const Current& current)
+    void checkNotNull(std::optional<Prx> prx, const char* file, int line, const Current& current)
     {
         if (!prx)
         {
@@ -27,7 +29,7 @@ namespace Ice
             std::ostringstream os;
             os << "null proxy passed to " << current.operation << " on object "
                << current.adapter->getCommunicator()->identityToString(current.id);
-            throw MarshalException{__FILE__, __LINE__, os.str()};
+            throw MarshalException{file, line, os.str()};
         }
     }
 
diff --git a/cpp/src/IceDiscovery/LookupI.cpp b/cpp/src/IceDiscovery/LookupI.cpp
index 68f91e26dc9..b490f882a81 100644
--- a/cpp/src/IceDiscovery/LookupI.cpp
+++ b/cpp/src/IceDiscovery/LookupI.cpp
@@ -480,13 +480,13 @@ LookupReplyI::LookupReplyI(const LookupIPtr& lookup) : _lookup(lookup) {}
 void
 LookupReplyI::foundObjectById(Identity id, optional<ObjectPrx> proxy, const Current& current)
 {
-    Ice::checkNotNull(proxy, current);
+    checkNotNull(proxy, __FILE__, __LINE__, current);
     _lookup->foundObject(id, current.id.name, *proxy);
 }
 
 void
 LookupReplyI::foundAdapterById(string adapterId, optional<ObjectPrx> proxy, bool isReplicaGroup, const Current& current)
 {
-    Ice::checkNotNull(proxy, current);
+    checkNotNull(proxy, __FILE__, __LINE__, current);
     _lookup->foundAdapter(adapterId, current.id.name, *proxy, isReplicaGroup);
 }
diff --git a/cpp/src/IceStorm/NodeI.cpp b/cpp/src/IceStorm/NodeI.cpp
index aa970d8fb50..023d87ca660 100644
--- a/cpp/src/IceStorm/NodeI.cpp
+++ b/cpp/src/IceStorm/NodeI.cpp
@@ -800,7 +800,7 @@ NodeI::ready(
     int64_t generation,
     const Ice::Current& current)
 {
-    Ice::checkNotNull(coordinator, current);
+    checkNotNull(coordinator, __FILE__, __LINE__, current);
     lock_guard lock(_mutex);
     if (!_destroy && _state == NodeState::NodeStateReorganization && _group == gn)
     {
diff --git a/cpp/src/IceStorm/TopicI.cpp b/cpp/src/IceStorm/TopicI.cpp
index f43a6231395..e0ecbca35e0 100644
--- a/cpp/src/IceStorm/TopicI.cpp
+++ b/cpp/src/IceStorm/TopicI.cpp
@@ -116,7 +116,7 @@ namespace
         optional<Ice::ObjectPrx>
         subscribeAndGetPublisher(QoS qos, optional<Ice::ObjectPrx> obj, const Ice::Current& current) override
         {
-            Ice::checkNotNull(obj, current);
+            checkNotNull(obj, __FILE__, __LINE__, current);
             while (true)
             {
                 int64_t generation = -1;
@@ -149,7 +149,7 @@ namespace
 
         void unsubscribe(optional<Ice::ObjectPrx> subscriber, const Ice::Current& current) override
         {
-            Ice::checkNotNull(subscriber, current);
+            checkNotNull(subscriber, __FILE__, __LINE__, current);
             while (true)
             {
                 int64_t generation = -1;
diff --git a/cpp/src/IceStorm/TransientTopicI.cpp b/cpp/src/IceStorm/TransientTopicI.cpp
index 999a9a83af9..3465eefe528 100644
--- a/cpp/src/IceStorm/TransientTopicI.cpp
+++ b/cpp/src/IceStorm/TransientTopicI.cpp
@@ -137,7 +137,7 @@ TransientTopicImpl::getNonReplicatedPublisher(const Ice::Current&) const
 optional<Ice::ObjectPrx>
 TransientTopicImpl::subscribeAndGetPublisher(QoS qos, optional<Ice::ObjectPrx> obj, const Ice::Current& current)
 {
-    Ice::checkNotNull(obj, current);
+    checkNotNull(obj, __FILE__, __LINE__, current);
     Ice::Identity id = obj->ice_getIdentity();
 
     auto traceLevels = _instance->traceLevels();
@@ -183,7 +183,7 @@ TransientTopicImpl::subscribeAndGetPublisher(QoS qos, optional<Ice::ObjectPrx> o
 void
 TransientTopicImpl::unsubscribe(optional<Ice::ObjectPrx> subscriber, const Ice::Current& current)
 {
-    Ice::checkNotNull(subscriber, current);
+    checkNotNull(subscriber, __FILE__, __LINE__, current);
     Ice::Identity id = subscriber->ice_getIdentity();
 
     auto traceLevels = _instance->traceLevels();
@@ -221,7 +221,7 @@ TransientTopicImpl::getLinkProxy(const Ice::Current&)
 void
 TransientTopicImpl::link(optional<TopicPrx> topic, int cost, const Ice::Current& current)
 {
-    Ice::checkNotNull(topic, current);
+    checkNotNull(topic, __FILE__, __LINE__, current);
     TopicInternalPrx internal(*topic);
     auto link = internal->getLinkProxy();