diff --git a/Phys/ParticleCombiners/include/CombKernel/ParticleCombiner.h b/Phys/ParticleCombiners/include/CombKernel/ParticleCombiner.h
index 8b397f6fd9edd74d1dcc9490f6de8def9f62b918..639d6ab15a016b5dc56e54464ac7d69be0b216ae 100644
--- a/Phys/ParticleCombiners/include/CombKernel/ParticleCombiner.h
+++ b/Phys/ParticleCombiners/include/CombKernel/ParticleCombiner.h
@@ -168,8 +168,13 @@ public:
    */
   template <std::size_t... Is>
   static auto input_names( std::index_sequence<Is...> ) {
+#ifdef GAUDI_FUNCTIONAL_CONSTRUCTOR_USES_TUPLE
+    return std::make_tuple( KeyValue{"Input" + std::to_string( Is + 1 ), ""}...,
+                            KeyValue{"StandardGeometryTop", "/dd/Structure/LHCb"} );
+#else
     return std::array{KeyValue{"Input" + std::to_string( Is + 1 ), ""}...,
                       KeyValue{"StandardGeometryTop", "/dd/Structure/LHCb"}};
+#endif
   }
 
   StatusCode initialize() override {
diff --git a/Phys/ParticleCombiners/include/CombKernel/ThOrCombiner.h b/Phys/ParticleCombiners/include/CombKernel/ThOrCombiner.h
index c9ffcd5eba30448050ac54b9dba5b18e996f5a73..fbcd76008dbb9c24ae10275a81c435370daa8fe1 100644
--- a/Phys/ParticleCombiners/include/CombKernel/ThOrCombiner.h
+++ b/Phys/ParticleCombiners/include/CombKernel/ThOrCombiner.h
@@ -420,13 +420,17 @@ namespace ThOr {
 
     template <std::size_t... Is>
     static auto input_names( std::index_sequence<Is...> ) {
+#ifdef GAUDI_FUNCTIONAL_CONSTRUCTOR_USES_TUPLE
+      return std::make_tuple( KeyValue{"InputUniqueIDGenerator", LHCb::UniqueIDGeneratorLocation::Default},
+                              KeyValue{"Input" + std::to_string( Is + 1 ), ""}... );
+#else
       return std::array{KeyValue{"InputUniqueIDGenerator", LHCb::UniqueIDGeneratorLocation::Default},
                         KeyValue{"Input" + std::to_string( Is + 1 ), ""}...};
+#endif
     }
 
     Combiner( const std::string& name, ISvcLocator* pSvcLocator )
-        : base_t{name, pSvcLocator, input_names( std::index_sequence_for<InputTypes...>{} ), {KeyValue{"Output", ""}}} {
-    }
+        : base_t{name, pSvcLocator, input_names( std::index_sequence_for<InputTypes...>{} ), KeyValue{"Output", ""}} {}
 
     StatusCode initialize() override {
       StatusCode sc = base_t::initialize();