What's the latest version of Roslyn my analyzer can target if I support VS2015?

Question

I'm writing a Roslyn diagnostic analyzer that should work on VS2015 and later editions. I want to know the latest version of Microsoft.CodeAnalysis I can use with my project and still support VS2015. I need to use an API that was added in Roslyn 1.2.0 (AnalysisContext.EnableConcurrentExecution), but I think that version of Roslyn isn't included with VS2015 (IIRC, only VS2017 supports C# 7). Does this mean I can't use this API in my analyzer?

Ovalle

Why do you "need to" call AnalysisContext.EnableConcurrentExecution? If you don't, your analyzer will work just the same from a functional point of view (though maybe a bit slower). – Fender

@KrisVandermotten Okay, I didn't need to, I wanted to. The question still holds. – Ovalle

Yes, the question still holds indeed. And the accepted answer tells you what you need to know. If (and only if) you are ok with only supporting VS 2015 Update 2 or later, you can call EnableConcurrentExecution. – Fender

Answer 1

Yes, Roslyn 2.3.0 will only work on Visual Studio 2017.3 and newer.

In general the mappings of Roslyn to Visual Studio versions works like this:

Roslyn 1.0.x -> Visual Studio 2015.0 (RTM)

Roslyn 1.1.x -> Visual Studio 2015.1 (Update 1)

Roslyn 1.2.x -> Visual Studio 2015.2 (Update 2)

Roslyn 1.3.x -> Visual Studio 2015.3 (Update 3)

Roslyn 2.0.x -> Visual Studio 2017.0 (RTM)

Roslyn 2.1.x -> Visual Studio 2017.1.x

Roslyn 2.2.x -> Visual Studio 2017.2.x

Roslyn 2.3.x -> Visual Studio 2017.3.x

Roslyn 2.4.x -> Visual Studio 2017.4.x

Roslyn 2.6.x -> Visual Studio 2017.5.x

Roslyn 2.7.x -> Visual Studio 2017.7.x

Roslyn 2.8.x -> Visual Studio 2017.7.x

Roslyn 2.9.x -> Visual Studio 2017.8.x

Roslyn 2.10.x -> Visual Studio 2017.9.x

Roslyn 3.0.x -> Visual Studio 2019.0 (RTM)

Subnormal

+1 This is very helpful but is this documented somewhere? I had a hell of a time finding any info on this (I mean, this post is it). – Mayence

Does it matter which Roslyn version you pick in your analyzer project except that it gives you access to the APIs you want at compile time? Is the Roslyn version used at runtime determined by the host that's using the analyzer? – Pope

Full list: learn.microsoft.com/en-us/visualstudio/extensibility/… – Googolplex