diff --git a/include/armnn/Types.hpp b/include/armnn/Types.hpp
index 438b6be..53aa437 100644
--- a/include/armnn/Types.hpp
+++ b/include/armnn/Types.hpp
@@ -118,6 +118,8 @@
 protected:
     IDeviceSpec() {}
     virtual ~IDeviceSpec() {}
+public:
+    virtual const BackendIdSet& GetSupportedBackends() const = 0;
 };
 
 /// Type of identifiers for bindable layers (inputs, outputs).
diff --git a/src/armnn/DeviceSpec.hpp b/src/armnn/DeviceSpec.hpp
index 834ce09..35923e6 100644
--- a/src/armnn/DeviceSpec.hpp
+++ b/src/armnn/DeviceSpec.hpp
@@ -19,7 +19,7 @@
 
     virtual ~DeviceSpec() {}
 
-    virtual const BackendIdSet& GetSupportedBackends() const
+    virtual const BackendIdSet& GetSupportedBackends() const override
     {
         return m_SupportedBackends;
     }