---
layout: releasenotes
title: 'Mono 5.8.1 Release Notes'
version: 5.8.1
releasedate: '2018-03-26'
---

Mono 5.8.1 is a service release for the Mono 5.8 series.

## Release History

-   5.8.1.0 - Visual Studio for Mac Release *(26 March 2018)*

## Bug Fixes

-   GitHub [#6658](https://github.com/mono/mono/issues/6658) - `NullReferenceException` at `op_Increment` when using assemblies compiled by `csc` rather than `mcs` that use [native types](https://docs.microsoft.com/xamarin/cross-platform/macios/nativetypes) such as `nuint` and that have specially-handled assembly names like Xamarin.Mac.dll.
-   GitHub [#7472](https://github.com/mono/mono/issues/7472) - Incorrect `NullReferenceException` when using extension methods on null instances as `Action` or `Func` arguments or variables.

## Contributors

Jonathan Chambers, Ludovic Henry, Mathieu Bourgeois