Model-driven engineering advocates the use of models to describe and automate many software development tasks. The syntax of modelling languages is defined by meta-models, making them essential artefacts. A combination of product line engineering methods and meta-models has been proposed to enable specification of modelling language variants, e.g., to describe a range of systems. However, there is a lack of techniques for ensuring syntactic correctness of all meta-models within a family (including their OCL constraints), and semantic correctness related to properties of individual instances of the different variants. The absence of verification methods at the product-line level can cause synthesis of ill-formed meta-models and problematic feature combinations whose effect at the instance level may go unnoticed.

To attack this problem, we propose an approach to lifting both the meta-model syntax checking and the satisfiability checking of properties of individual meta-model instances, to the product-line level. We validate the approach via a prototype tool called Merlin, and report on several experiments that show the advantages of our method w.r.t. an enumerative analysis approach.