Formalising Futures and Promises in Viper

National audienceFutures and promises are respectively a read-only and a write-once pointer to a placeholder in memory. They are used to transfer information between threads in the context of asynchronous concurrent programming. Futures and promises simplify the implementation of synchronisation mechanisms between threads. Nonetheless they can be error prone as data races may arise when references are shared and transferred. We aim at providing a formal tool to detect those errors. Hence, in this paper we propose a proof of concept by implementing the future/promise mechanism in Viper: a verification infrastructure, that provides a way to reason about resource ownership in programs