# Two-Variable Separation Logic and Its Inner Circle

```@article{Demri2015TwoVariableSL,
title={Two-Variable Separation Logic and Its Inner Circle},
author={Stephane Demri and Morgan Deters},
journal={ACM Transactions on Computational Logic (TOCL)},
year={2015},
volume={16},
pages={1 - 36}
}```
• Published 21 March 2015
• Philosophy
• ACM Transactions on Computational Logic (TOCL)
Separation logic is a well-known assertion language for Hoare-style proof systems. We show that first-order separation logic with a unique record field restricted to two quantified variables and no program variables is undecidable. This is among the smallest fragments of separation logic known to be undecidable, and this contrasts with the decidability of two-variable first-order logic. We also investigate its restriction by dropping the magic wand connective, known to be decidable with…

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