Mono 4.0.0 Release Notes

http://www.mono-project.com/docs/about-mono/releases/4.0.0/

by tizoc • 11 years ago

171 62 11 years ago

And with this release we see the beginning of the convergence of the Mono and Microsoft codebases. I'm glad Mono will be more reliable as a result, there have always been persistent reliability and compatibility issues that the Mono team hasn't been able to really fix.

It's also a little sad, in a way. It relegates Xamarin to maintainers of a distribution for another operating system. At the end of the day, C# and .NET are now officially first class citizens on Linux. Speaking as someone that actually ran Mono in production for around a year before realizing it was a ridiculous waste of time and money and switching to Windows Server 2012 after finding and filling dozens of untrackable deployment and stability issues in ASP.NET under Mono, I'm definitely not ready to switch back anytime soon, but Mono is definitely foreseeably a real option.

tacos5• 11 years ago

The Mono team did an amazing job, and they actually had a lot of support deep within Microsoft all along. But yeah, I think it's okay to say "it never really worked."

(And there's nothing wrong with being a port factory that deals with obscure path issues all day. That's why they give you a paycheck...)

Still, Xamarin is doing a LOT more than just Mono, much of it extraordinary.

Also delivering something that actually works is an ego boost. Probably attracts the "right" kind of employee for the task, too.

smosher_4• 11 years ago

But yeah, I think it's okay to say "it never really worked."

I don't. I mean yes mono <4.0 has a lot of problems, but it works well enough for me to shell out money for applications running on mono and be happy about it.

azakai4• 11 years ago

It's also a little sad, in a way. It relegates Xamarin to maintainers of a distribution for another operating system.

I'm not sure I understand what you mean here. As I understand things, Mono is still keeping its runtime - JIT, garbage collector (the release notes here mention optimizations to SGen), etc. That means Mono isn't nor is it planning to be "just" a distro for Microsoft's .NET. (But it is using more and more Microsoft library and compiler code.)

coldtea4• 11 years ago

I'm not sure I understand what you mean here. As I understand things, Mono is still keeping its runtime - JIT, garbage collector (the release notes here mention optimizations to SGen), etc.

So? Who will still use those, if there's a fully supported MS based (+ some open source effort for some edges) alternative?

nickysielicki4• 11 years ago

At the end of the day, C# and .NET are now officially first class citizens on Linux.

C# and .NET will never be first class citizens on unix. This is by design.

http://en.wikipedia.org/wiki/Embrace,_extend_and_extinguish

happycube2• 11 years ago

Maybe not first class, but I think Microsoft's eaten a bit of humble pie (ala IBM ~15-20 years ago when they started ramping up Linux efforts) and generally playing nice.

Who ten years ago would have imagined so much of .NET would wind up MIT licensed, not just some 'shared source' malarky, on Sourceforge's ~2015 successor?

This isn't the Microsoft of the Halloween memos anymore.

Locke16894• 11 years ago

You're aware the past can only inform the future, not predict it?

coldtea4• 11 years ago

That's a 15+ years off slogan from the Desktop/Browser wars era...

Nowhere near as relevant or enlightening as you think it is in 2015 (wasn't much of an analysis in 1998 either, but still...)

j_s• 11 years ago

It will be interesting to see if anyone releases an open-source port of the MS runtime to ARM... Xamarin could wind up left with only their proprietary cross-platform UI toolkit!

yareally4• 11 years ago

Runtime is already open and runs on Linux, one just has to cross compile it, optimize for mobile and do the bindings and such that Xamarin already does. That's still quite a bit of legwork since Xamarin has been doing it for some years now. Not saying someone couldn't do it, but it would take a good amount of time to be on the level Xamarin is in stability and performance.

I pay for Xamarin personally and think it's well worth it if doing cross-platform compared to the alternatives out there. I'd continue to do so until there's a very stable open sourced alternative. However, I think Xamarin knows such a possibility could happen and that's why they primarily target enterprise and not individual developers.

https://github.com/dotnet/coreclr

moonchrome• 11 years ago

For Android this could be possible.

For iOS I think you would have to figure out how to hook up MS runtime to a LLVM AOT compiler and then do all the work Mono team did to make sure libraries compile/work without JIT.

I really hope Xamarin guys follow Microsoft lead and make entry level version of their product free. It's not just about the ~25$ per month, it's about community as well - say some guy X is maintaining .NET library Y. I write up a port/pull for Xamarin - X goes "sweet but I can't test that since I don't own Xamarin and I can't even include it in my test suite to not break it further". Now I have to maintain a branch of Y for Xamarin and most other people are likely not going to find it or willing to use it.

I don't know which % of their profit comes from the indie licensing but if it's not significant as I suspect I would hope that they see this - it will help both their adoption and the OSS community build tools for their product.

gnud• 11 years ago

We no longer build or package reference assemblies for the .NET 2.0, .NET 3.5 or .NET 4.0 APIs. We only support now the .NET 4.5 assemblies as well as the mobile-based profiles.

Does that go for the runtime as well? Does this mean I can no longer run a (compiled) .NET 2.0 application on Linux?

akoeplinger3• 11 years ago

No, it should run on the 4.5 profile just fine as backwards compatibility in the .NET APIs is very good.

Please note that this is still a draft and the .NET 2.0/3.5 assemblies will likely reappear as reference assemblies (i.e. containing only method signatures in IL, so you can build against those profiles but not run on them).

glutamate2• 11 years ago

Tail call optimisation in F# ?

saosebastiao2• 11 years ago

Wait...mono doesn't do tail call optimization with f#???

glutamate2• 11 years ago

It is (or was) complicated, you could stack overflow on two mutually recursive functions or tail calling inside continuations.

knocte5• 11 years ago

This is a draft. Mono 4.0 hasn't been released yet. Who keeps publishing mono's release-notes drafts as HN news?

akoeplinger3• 11 years ago

I added a note to the page to make this clear.

HN mods: can we get a "(draft)" note added to the submission title as well?

knocte5• 11 years ago

thanks Alex

golergka2• 11 years ago

This is on HN homepage now, so the question you should ask is not who published it, but who upvoted it. And the answer is, at least 158 different people who found it useful.

coldtea4• 11 years ago

People who want to learn some details about this upcoming release before it happens?

thurn• 11 years ago

I look forward to being able to use this all in Unity3D in 7 years.

azakai4• 11 years ago

Unity is moving away from Mono anyhow,

http://blogs.unity3d.com/2014/05/20/the-future-of-scripting-...

so updates in Mono are irrelevant to Unity.

golergka2• 11 years ago

What? That's what this post says:

we will also be upgrading to recent versions of the Mono C# compiler, base class libraries, and runtime for use in the editor
We will continue to use the Mono C# compiler (and perhaps later, Roslyn). We will continue to use the Mono class libraries. All currently supported features and 3rd party libraries which work with Mono AOT should continue to work with IL2CPP. We are only seeking to provide a replacement for the Mono VM and AOT compiler, and will keep on leveraging the wonderful Mono Project.

needusername• 11 years ago

Unity is moving away from Mono anyhow,

I don't know man. Mono moved away from Boehm GC to a real gc (SGen) because it never really worked for them bespite feeding it a lot of metadata. Others before them have found out that tanspiling to C/C++ isn't really that great (some of the more recent ones where HipHop PHP).

rajeevk• 11 years ago

Just curious.. Why cant the mono team replaces almost whole of their codebase with the code Microsoft open sourced? Is there anything stopping them to do that? Maybe licensing issues?

knocte5• 11 years ago

You know that Mono is cross-platform and Microsoft code only runs in Windows right?

gfodor• 11 years ago

Is this true?

akoeplinger3• 11 years ago

Because it is a lot of work and takes time to integrate the pieces MS open sourced :)

There are also a few cases where the code needs to be tweaked so it works correctly on Mono and the platforms it runs on.

azakai4• 11 years ago

First, the code Microsoft released does not build and run on all platforms. They promised Linux support, and are working on it now in the open, but it's not there yet. So Mono can't just adopt the Microsoft .NET VM without losing features.

Second, Microsoft is open-sourcing their whole VM - JIT, GC, as well as compiler and libraries. Compiler and library code is already being utilized by Mono, and more all the time. However, Mono doesn't even have plans to replace their JIT or GC with .NET's, as far as I know (and the Trello board linked to in the article seems consistent with that).

Could Mono do that (once Microsoft's builds on Linux and other platforms Mono needs)? Yes in theory, but it would mean abandoning all the massive amount of work they put into their VM over many years. I don't know whether it would be rational or not to do so.

Licensing isn't a problem for Mono to use Microsoft code. However, Mono's runtime is LGPL licensed, and this has been a source of revenue for them (people pay Xamarin for licenses for platforms like consoles where LGPL is a problem). So to replace the Mono VM with Microsoft's could be a step back there.

Locke16894• 11 years ago

I can't speak for mono, but converging makes sense where it makes sense -- if mono has a solid implementation of something they consider core and the MS implementation isn't trivial to port, I don't see a good reason to port it.

migueldeicaza2• 11 years ago

We are working on replacing those parts that we can.

But there are several issues:

* reference source code not being portable and not working on Unix. * complex dependencies between the portable and non portable pieces * some bits were only released recently, and without those it was not possible to port other chunks * dynamic happy code high prevents some code from being adopted as Mono can be used as a full static compiler on iOS, Xbox and Playstation.

So as time permits we will bring those over.

We also plan on supporting the "core" model where our contributions will flow back upstream.

But "core" is still a bit undefined

jordz• 11 years ago

This draft looks great. We've been running Mono since December 2013 for a fairly big data processing framework - 2014 saw us move it into production. We've had our fair share of really horrible performance issues, runtime issues and the rest. 4.0 has some stuff in that fixes many of those nasty issues!

Awesome work by team Xamarin + Contributors.

migueldeicaza2• 11 years ago

It is a shame that this got submitted before we actually published the code. It is Easter and many of our engineers are taking these days off.

The release notes are also incomplete and not ready for publishing

Miguel

tizoc• 11 years ago

Sorry, saw it on reddit as "Mono 4 Released"[1] and reposted here, without noticing it was just a draft (the "THIS IS A DRAFT" comment wasn't there at the moment).

[1] http://www.reddit.com/r/programming/comments/31ezp0/mono_4_r...

Mono 4.0.0 Release Notes

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