@@ -180,6 +180,13 @@ StaticCallInterfaceDescriptor<DerivedDescriptor>::GetStackParameterCount() {
          DerivedDescriptor::GetRegisterParameterCount();
 }
 
+// static
+template <typename DerivedDescriptor>
+constexpr Register
+StaticCallInterfaceDescriptor<DerivedDescriptor>::GetRegisterParameter(int i) {
+  return DerivedDescriptor::registers()[i];
+}
+
 // static
 constexpr Register FastNewObjectDescriptor::TargetRegister() {
   return kJSFunctionRegister;
 
@@ -469,10 +469,8 @@ class StaticCallInterfaceDescriptor : public CallInterfaceDescriptor {
   static constexpr inline int GetRegisterParameterCount();
   static constexpr inline int GetStackParameterCount();
   static constexpr inline Register* GetRegisterData();
+  static constexpr inline Register GetRegisterParameter(int i);
 
-  static constexpr inline Register GetRegisterParameter(int i) {
-    return DerivedDescriptor::registers()[i];
-  }
   explicit StaticCallInterfaceDescriptor(CallDescriptors::Key key)
       : CallInterfaceDescriptor(key) {}