diff --git a/Code/Mantid/Framework/DataObjects/src/EventWorkspace.cpp b/Code/Mantid/Framework/DataObjects/src/EventWorkspace.cpp
index 64b0db718cd64e0a5f62e010ac086cdf7f10ce0e..0c41329627ad022d03eca4afa94ce7b7562eeb0c 100644
--- a/Code/Mantid/Framework/DataObjects/src/EventWorkspace.cpp
+++ b/Code/Mantid/Framework/DataObjects/src/EventWorkspace.cpp
@@ -981,7 +981,7 @@ namespace DataObjects
   public:
     /// ctor
     EventSortingTask(const EventWorkspace * WS, int wiStart, int wiStop, EventSortType sortType, size_t howManyCores, Mantid::API::Progress * prog)
-    : m_wiStart(wiStart), m_wiStop(wiStop),  m_sortType(sortType), m_howManyCores(howManyCores), m_WS(WS), prog(prog)
+    : Task(), m_wiStart(wiStart), m_wiStop(wiStop),  m_sortType(sortType), m_howManyCores(howManyCores), m_WS(WS), prog(prog)
     {
       m_cost = 0;
       if (m_wiStop > m_WS->getNumberHistograms())
diff --git a/Code/Mantid/Framework/Kernel/test/ThreadPoolTest.h b/Code/Mantid/Framework/Kernel/test/ThreadPoolTest.h
index facf6e55ae2aa1f53c94bf2753c20bc3929f1218..2a028f2f6e98abc7546244b7bd743528eb8c6c55 100644
--- a/Code/Mantid/Framework/Kernel/test/ThreadPoolTest.h
+++ b/Code/Mantid/Framework/Kernel/test/ThreadPoolTest.h
@@ -101,7 +101,7 @@ class TaskThatAddsTasks : public Task
 public:
   // ctor
   TaskThatAddsTasks(ThreadScheduler * scheduler, size_t depth)
-  : m_scheduler(scheduler), depth(depth)
+  : Task(), m_scheduler(scheduler), depth(depth)
   {
     // Use a randomized cost function; this will have an effect on the sorted schedulers.
     m_cost = rand();
diff --git a/Code/Mantid/Framework/Kernel/test/ThreadSchedulerTest.h b/Code/Mantid/Framework/Kernel/test/ThreadSchedulerTest.h
index 91e5d2ebaabed9c3a03a0c915ab8bfbaa7baad59..b1c0cabc10796cf5a58adbc96654bd66e2325983 100644
--- a/Code/Mantid/Framework/Kernel/test/ThreadSchedulerTest.h
+++ b/Code/Mantid/Framework/Kernel/test/ThreadSchedulerTest.h
@@ -21,8 +21,8 @@ public:
   class TaskDoNothing : public Task
   {
   public:
-    TaskDoNothing() {}
-    TaskDoNothing(double cost) {m_cost = cost;}
+    TaskDoNothing() : Task() {}
+    TaskDoNothing(double cost) : Task() {m_cost = cost;}
 
     ~TaskDoNothing()
     {