Compiling the C++ VM

Antal Szabó

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Oct 28, 2012, 5:51:05 PM10/28/12

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Hi!

How can I compile the C++ magpie VM?

Or is it not functional yet? I would like to try it.

BTW, I like the design of magpie a lot, although I woul like if it would be compiled :)

Bob Nystrom

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Oct 29, 2012, 10:09:52 AM10/29/12

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On Sun, Oct 28, 2012 at 2:51 PM, Antal Szabó <szabo.a...@gmail.com> wrote:

Hi!

How can I compile the C++ magpie VM?

Great question. I should write some docs on that. :)

The C++ VM generally uses gyp to generate project files / makefiles for your OS. However, I'm in the process of moving to OS X Mountain Lion my machine so right now there's a hand-maintained xcodeproject in the repo. If you're on Mountain Lion, just open that and build and you should be good to go. It builds into build/.

If you're on Windows or Linux:

1. Download gyp. Magpie uses that to generate project files / makefiles for your OS. I think I usually just the clone the repo from here: https://github.com/martine/gyp.

2. Run gyp from within the root directory of the magpie repo:

$ cd path/to/magpie

$ path/to/gyp/gyp --depth=1

That should create a Makefile, Visual Studio solution that you can use. Let me know if you run into any problems. :)

Or is it not functional yet? I would like to try it.

It's getting there, but there's still a long ways to go. The test/ directory has all of the tests that pass on the VM, so that gives you an idea of its capabilities.

BTW, I like the design of magpie a lot, although I woul like if it would be compiled :)

Thanks! I really like having a VM that doesn't require ahead-of-time compilation. It makes it feel more like a quick scripting language to me.

However, I have thought about also having some ahead-of-time compilation. The VM itself uses bytecode internally, so one option would be compile to bytecode and then having a runtime that can handle that but doesn't include the parser, compiler, etc.

It's not a high priority right now, but it could be fun.

Cheers!

- bob

Szabó Antal

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Oct 29, 2012, 6:23:42 PM10/29/12

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Hi!

Thanks for the help!

I made some changes, and now it works perfectly on Windows!
I made a pull request, so you can review the changes.

I also opened a new issue, which I found while compiling magpie, you
should take a look.

Antal Szabó

Bob Nystrom

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Oct 30, 2012, 10:12:42 AM10/30/12

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On Mon, Oct 29, 2012 at 3:23 PM, Szabó Antal <szabo.a...@gmail.com> wrote:

Hi!

Thanks for the help!

I made some changes, and now it works perfectly on Windows!

Awesome, this is great to hear.

I made a pull request, so you can review the changes.

Done. Nice code!

I also opened a new issue, which I found while compiling magpie, you should take a look.

Good catch. I had forgotten that I didn't pull all of the support for "else" in match expressions over from the Java interpreter. It's fully supported now. Thanks for noticing this.

Cheers!

- bob

Paul Woolcock

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Jan 9, 2013, 9:22:57 PM1/9/13

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Hello! Sorry to revive this thread, but I'm seem to be missing something. I have tried compiling the C++ VM on multiple different linuxes (linuces?), and every time, g++ gets stuck on ExprCompiler.cpp. It looks like every method that takes a `magpie::gc<magpie::Expr>` parameter is causing this error:

    error: cannot allocate an object of abstract type 'magpie::Expr'
    In file included from ../src/Syntax/Ast.h:223:0,
                                 ../src/VM/Method.h:4,
                                 ../src/Compiler/ExprCompiler.cpp:2:
    ../src/Syntax/Ast.generated.h:94:7: note:    because the following virtual functions are pure within 'magpie::Expr':

This goes on and on for pretty much every single method that takes a gc<Expr>. My C++ is a little rusty, but this seems like an odd error for *just* me to be getting...is there a compiler flag I need to turn on or something? Does anyone else see this?

Bob Nystrom

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Jan 9, 2013, 11:48:50 PM1/9/13

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On Wed, Jan 9, 2013 at 6:22 PM, Paul Woolcock <pwoo...@gmail.com> wrote:

Hello! Sorry to revive this thread, but I'm seem to be missing something. I have tried compiling the C++ VM on multiple different linuxes (linuces?), and every time, g++ gets stuck on ExprCompiler.cpp. It looks like every method that takes a `magpie::gc<magpie::Expr>` parameter is causing this error:

    error: cannot allocate an object of abstract type 'magpie::Expr'
    In file included from ../src/Syntax/Ast.h:223:0,
                                 ../src/VM/Method.h:4,
                                 ../src/Compiler/ExprCompiler.cpp:2:
    ../src/Syntax/Ast.generated.h:94:7: note:    because the following virtual functions are pure within 'magpie::Expr':

This goes on and on for pretty much every single method that takes a gc<Expr>.

Strange! Does it say which functions are missing? Feel free to throw some more error output spew here.

My C++ is a little rusty, but this seems like an odd error for *just* me to be getting...

Well, the set of people on Earth who've tried to build the Magpie VM at this point is probably pretty small, so this could very well mean 50% of all people who tried it are running into this issue. :)

is there a compiler flag I need to turn on or something? Does anyone else see this?

Not that I'm aware of, but I haven't personally had a chance to try the Linux build yet (I'm on Mac). In theory, thanks to gyp, it should Just Work (TM), but gyp is a little... uh... odd sometimes.

For what it's worth, I'm doing a bunch of hacking on the gyp files right now (I'm integrating libuv into Magpie) so that may or may not affect this when that lands.

- bob

Paul Woolcock

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Jan 10, 2013, 7:29:30 AM1/10/13

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Ok, you asked for it :)

~/code/magpie/1$ make
CXX(target) out/Debug/obj.target/magpie/../src/Base/MagpieString.o
CXX(target) out/Debug/obj.target/magpie/../src/Compiler/Compiler.o
CXX(target) out/Debug/obj.target/magpie/../src/Compiler/ExprCompiler.o
../src/Compiler/ExprCompiler.cpp: In member function ‘void magpie::ExprCompiler::compile(magpie::Module*, int, magpie::gc<magp
ie::Pattern>, magpie::gc<magpie::Pattern>, magpie::gc<magpie::Pattern>, magpie::gc<magpie::Expr>)’:
../src/Compiler/ExprCompiler.cpp:128:48: error: cannot allocate an object of abstract type ‘magpie::Expr’