Mono C# Compiler Compiles Itself

Bob Smith writes: "Miguel just commited the last patch nessisary to get Mono's C# compiler to compile itself. After 7 odd months, MCS is now self hosting." jbarn adds: "Mono-list email is here."

Comments

Re:good news,

[Ace Rimmer]

It depends on how this C# is intended to be use. If it is only to leech from MS .net it's not an alternative - you'll still be tied to MS thoughts of a row ahead...

More developers to mono

[famazza]

I think it'll bring more developers to mono, and also more accurate code. Many developers couldn't code with quality due to the lack of a linux compiler, to develop the mono framework developers should go to windows and compile at .net compiler.

It's a big step forward. Congratulations

Re:a dumb question

[Anonymous Coward]

From a software development stance, it's basically just a fundamental benchmark to show that the code is solid, and the language is mature.

Obviously, it's not magic: you won't get a Lisp compiler that was written in C to compile itself, ever.

Samba anyone ?

[MosesJones]

Isn't it wonderful having C# and .NET on Linux, after all they won't have the problems that Samba boys have trying to keep up with MS deliberately changing things to stop them, and it won't be miles worse.

Mono is a nice idea, but unfortunately .NET isn't a revolution, its a way to build poor quality mainframes, lots of boxes, poor IO. In terms of distribution there is none. Full credit to the guys for doing this but it does remind me of a Larson cartoon, you know the one with the Sheep Bar and the line

"What do you know, I'm a follower too"

Re:Samba anyone ?

[Craig Maloney]

Having the compiler is nice, but unfortunately it doesn't preclude the perennial "catch-up" game that Microsoft is so fond of playing. The compiler is just one part of the puzzle... there's libraries and other assorted goodies that Linux will need which Microsoft can (and probably will) use some tom-foolery to make projects that ride on their coat-tails fall off.

Re:Samba anyone ?

[Ayende Rahien]

One of the biggest advantages of COM over CORBA is a *big* speed difference when running in-proc, while maintaining the same speed as CORBA as out-proccess & out-machine.

Re:I haven't heard good things about C#

[Ace Rimmer]

Well if one needs to develop a new language why, for God's sake, must everyone reimplement language at the nearly-the-same level as C?

And (unlike C), most of this so-called-portable languages use a stack VM machine. We don't know much about optimizing it in hardware and we don't have compilers capable doing that.

Guess why ppc (which is slower than most x86 in real apps) wins in float SPECs that much. Guess why hammer and p4 have sse2. Hint - 80387 design ... which is ... yes you got it.

Re: eat your own dogfood

[Anonymous Coward]

Self-hosting is always a huge win from a quality point of view. If the C# compiler is used to build itself, you know the bugs will be discovered and worked out quickly. I try to do something similar with all of my projects. Basically it's the 'eat your own dog food' philosophy - if you need your own product every day, you're super-motivated to fix it ;-)

Re:I haven't heard good things about C#

[Crimplene Prakman]

Hence Mono.

And and the controversy over the last while over whether our buddy Miguel et al are aiding and abetting the Redmond Ragtags, or opening the use of C#, quite likely one of the best all-round OOP RAD-able languages available, to the rest of the world outside those who don't mind being "locked in", as you say.

If nothing else, it will be yet another choice, and let's face it: if Linux allows for nothing else, it's choice. Choice in WMs, xterms, Desktop Environments, GUI toolkits, distros, package managers, and now choice in top-end populist OOP languages.

Re:I haven't heard good things about C#

[Crimplene Prakman]

If you think C# is at nearly the same level as C, you're very mistaken. It has much in common with Java, which is only related to C about as much as mice are to elephants.

C# and C share a letter and an ancestry, but have a completely different raison d'être, philosophy and implementation.

Re:a dumb question

[Alsee]

but what is so good about a compiler being able to compile itself?

A compiler being able to compile itself is an important "graduation ceremony". Any language that is incapable of compiling itself is obviously incomplete in some fundamental way.

Until a compiler compiles itself it is usally considered a "toy" language. There are 100's of them out there. They may be interesting academiclly, but they get no respect.

Sometimes the parent compiler can even have legal restrictions the use/distribution of it's output.

It's also sort of symbolic - the language is now self sustaining, and can break free. You can continue development in a "pure" enviorment of the new language.

-

Re:a dumb question

[cperciva]

what is so good about a compiler being able to compile itself?

Once the compiler can compile itself, you can stick a trojan into it and have a good chance of nobody noticing.

Great, but Microsoft will probably win in the end

[bjb]

I think its great that the non-Windows world is getting a C# compiler, however, it doesn't guarantee that we'll be fine in the future.

When you compile a C# application, you have a choice of compiling to the CLR bytecode, or to a native EXE. True, many apps from Microsoft will be written in C# in the near future, but they'll all be compiled into native code. Any 3rd party apps that get compiled will probably be built to native simply for the speed. Why would you want to want to build into bytecode when you can build it natively? Why release two separate binaries?

Of course, once Miguel's C# compiler catches up with the still-haven't-seen-it Microsoft C# compiler, Bill & Co. will definately come out with a way to extend it either by libraries or functionality that will leave Miguel in a constant state of catch-up.

Again, I appreciate the work, but I would be very surprised if it isn't simply "trying to catch our own tail".

Re:a dumb question

[Scooter]

Hmm interesting article - but having the compiler compile itself does not help you to do this - you could introduce such trojans to the compiler and then compile it with some other compiler - the result would be the same.

Re:Realitive?

[markmoss]

how mature is a compiler when it reaches self compiling capabilities? It looks like this milepost is "compiles itself", but "compiles itself correctly" is still a long time away. This probably means that nearly all the essential features are in the compiler now, but there is a lot of debugging left. When it compiles itself correctly, it will be close to done, but there are probably some features that aren't used by the compiler, and still have to be written and debugged. For instance, I can't see how a SQL database interface, or the ability to create a web page, would be relevant to compilers, but I would certainly want these capabilities in the library before I tossed out all my old programming tools.

Incidentally, self-compiling is a self-test that is only relevant to some languages. Many languages are quite useful in limited fields, but their primary features are not relevant to compilers, and they may lack features that are essential to compilers. It would be possible to write a compiler in BASIC, FORTRAN, or COBOL, but it would be insane to try it. OTOH, some languages were invented solely for writing compilers -- when it compiles itself correctly, it's done, but it's not much interest to anyone except a computer science professor specializing in compilers.

Self-compilation is a pretty good test for C-type compilers, because these are general purpose languages that are appropriate for compilers, among other things. It's a good test in another sense; quite often one of the problems in testing software is determining whether the output of the program is right or not. If you ran a CAD program (say) through the compiler, the compiler-writers could recognize a few gross errors (won't compile, won't run, erases the data file when you hit Save), but couldn't tell whether or not the finer nuances came out right. But they definitely know what a _compiler_ should do.

Is this progress?

[Anonymous Coward]

Once again, we have an announcement that makes me wonder if the open/free software community has a direction or just Brownian motion.

Sure, getting a compiler to this stage is a significant accomplishment. I've written compilers, and I know that self-compilation is probably the boggest (or at least most satisfying) milestone in the whole project.

But this does more to help MS than it does Linux, since it will remove yet another barrier to exit for people running Linux on servers. (Run C# and .Net on Linux, and it's easier to convert to Windows.) And remember, MS has concluded that Linux is not a threat on the desktop, but a very serious threat on servers. (I agree with both parts of that, FWIW.)

And as much as I hate to say it, this also provides ammunition to the people who claim that open source is very good at copying other projects' work, but terrible at innovating. Honestly, of all the high profile open source projects, how many of them are a significant innovation, and how many are merely an attempt to produce an equivalent of feature Z of Windows or Unix or Mac OS on Linux?

Re:Is this progress?

[kirkb]

The linux kernel itself certainly seems governed by Brownian motion. Linus himself suggests that development is random, and that evolution ends up sorting out the good stuff from the bad.

Check out http://kt.zork.net/kernel-traffic/kt20011217_146.h tml#1

Re:Request

[Hard_Code]

No C# is getting attention because it is part of .NET (or at least an language binding for the common language runtime, the basis of .NET), and lots of people give a damn about .NET and think it has significance (either bad or good). Not many people care about new compilers for functional languages that will never get above %0.01 acceptance. Actually, I would rather Slashdot *not* post frivolous stories about every compiler on earth.

Re:I haven't heard good things about C#

[Anonymous Coward]

taken from http://www.sys-con.com/java/article.cfm?id=1259

"When BEA Systems, IBM, HP, Borland, Oracle, and Sun Microsystems combine forces, there can only be one reason...and it isn't just mutual admiration.

This "Six Pack" of software giants has just joined the so-called Open Mobile Architecture initiative, or OMA, under the terms of which these global companies, inspired by the lead of Finnish phone dynamo Nokia last month, now agree to work together to facilitate the creation of mobile services - by standardizing how mobile devices connect to the Internet.

One notable giant is missing from the OMA line-up to date...Microsoft Corp."

I respect gnome guys but still dont know why not go
with java that was tons of support from big companies.
We see more and more alliances agains Microsoft.Why are open source community chasing Microsoft ?

ctyu

Busy Miguel

[MicroBerto]

Does Miguel seem to be overworked? Every single Gnome/Ximian announcement I've seen has his name in it. While I'm sure he's one badass dude, should he stick within just a few projects so that he doesn't go anymore insane than necessary?

EMCA doesn't mean Sh*t!

[bryanbrunton]

Microsoft has also submitted their implementation of Javascript (which they call JScript) to the EMCA. There are untold deviatations from what they submitted to the EMCA and bugs that will never be addressed by MS.

Good luck to the Mono development staff. A typical days work will consist of ensuring that bug #34433 behaves exactly like the bug in the MS code.

If they can't guarantee 100% bug-infested compatibility, then Mono is worthless.

Re:Mono?

[hetairoi]

hmmm, according to the fish it means "monkey". I don't get it, but I'm neither quick of wit nor a speculater. Maybe he is "monkeying" around with Macro$oft? I always thought it was odd that they were trying to infect computers with mononucleosis (see, I told you about my lack of wit).

Re:Get Your Hands Off My Pointers

[spacehug]

erm ... C# has pointers. Or were you referring to Java? ;)

Re:Microsoft and "standards"

[SerpentMage]

You are right on all of your points. But I ask the following. Can your HP-UX station use authentication that allows it to hook into Active Directory with all bells and whistles? Probably not.

It is not that Microsoft changes the basics. That is pretty easy to catch up to. What is more problematic is keeping up.

Let me explain. Lets say that I build an application using the Windows API (actually am). Everything works fine until the user starts using it on Windows XP or Windows 2000. You may ask why? Well according to the new security rules the application must only save content under the "My Documents" folder and not the folder installed to or something else. So now you are wondering how do I get access to the "My Documents" folder? The answer is a brand new API that is only available in a modern Platform SDK because when Visual C++ was released the API did not exist.

Do you see the issue? It is not that they break backward compatibility. It is that they introduce new rules which require you force upgrade your code. And that will happen with .NET. That is also why Miguel is dreaming about doing .NET on LINUX.

Re:Microsoft and "standards"

[spitzak]

This is exactly the sort of crap that MicroSoft does and why programmers hate it.

If you say that "MyDocuments" is equivalent to the Unix "home" directory, notice that on Unix the method to get this information is to call getenv("HOME"), while apparently on MicroSoft it is the new getMyDocumentsDirectory() call. Notice that the Unix solution reuses a current interface. If home directories did not exist before and they were added to Unix, most systems (like perl, etc) would already have the getenv() call and could immediately take advantage of it. The MicroSoft solution requires perl to be recompiled to call this.

I can find no clearer explanation as to why software engineers hate MicroSoft.

And they definately do this to break things. They have getenv() and a zillion other things (registry, for instance) to look up a string such as the MyDocuments directory name, but they insist on adding a new call. The fact is the engineers at MicroSoft are not idiots and it should be obvious that there are better ways to do this than adding new calls, but they are also blinded by absolute hatred for anything outside MicroSoft that they will gladly throw good engineering out in order to force people to stick to their platform.

Not enough C#

[GCP]

*And* not enough functional language articles.

One thing that disturbs me is how difficult it is for an elegant new language to replace the old hairballs that no longer resemble anything that any sensible person would have designed and are no longer used for what they were originally designed for.

New languages require extraordinary advantages outside the language itself for them to stand a chance at significant popularity. C# is the first since Java to have enough "outside" advantages to make it a realistic candidate to replace C++ for GUI apps.

I'd love to see some of the best functional languages get enough attention that maybe one of them could be in the right place at the right time to also join the exclusive club of Languages That Employers Actually Care About. More attention on Slashdot couldn't hurt.