10 April 2013

Nuitka needs you - a call for help

Update 3

And the first point has been done too, Python3.3 is now fully supported, including yield from syntax.

Update 2

The third point, Windows 64 support has been done as well. Turns out, that I do in fact own only Win64 systems, and with MSVC support in place, only a few portability fixes were needed.

Help with the other point, “re-formulation of yield”, would still be more than welcome, and no signs of progress there yet. So stop thinking “you could”, enter telling people “you did” mode.

Update

The second point, Fibers implementation for Windows, has been done. Thanks for the help you people provide. The next release will contain it.

Hello everybody,

the Python compiler Nuitka has come an ever longer way, and currently I have quite a bunch of issues, that I believe could well need your help. These are all issues of some important and significance, yet self contained jobs that you may enjoy.

Note

You can check the page What is Nuitka? for clarification of what it is now and what it wants to be.

  • Python 3.3 - reformulation of yield from needed.

    As you can see, covering all the CPython 2.6, 2.7, and 3.2 language features is already something. Also CPython 3.3 is now working on a basic level. Other projects are far, far away from that.

    Many language constructs, such as the with statement are re-formulated into other constructs. This makes it possible to work with a simple core for optimization, and to reduce the complexity a lot. For the with statement case, it’s changed to try/finally and try/except statements, together with a few temporary variables. Check the Nuitka source of it:

    ReformulationWithStatements.py

    There is also descriptions of all these re-formulations in the Developer Manual so you can see how this is done.

    Now check PEP 380 for the details of it, and your task would be to come up with a re-formulation of yield from statements to the semantically equivalent.

    The benefit is, you are working on a totally self-contained level. The re-formulation only needs to use ast node information, and turn that into Nuitka nodes. The problem will be fully solved this way.

    And once we have this, we can pronounce CPython3.3 as fully supported. So if you would like to see this happen, please join.

  • Windows - MSVC support needs low level code help

    update

    This is now done.

    The support for MSVC is already mostly there. If you execute the environment setting script, and use Nuitka under Windows, it will work. The only problem is that for the generator functions, Nuitka is using a concept called “Fiber”, which is basically just switching C stacks, so called co-routines.

    It works great for Linux and UNIX. For Windows, Fibers are currently using threads, which wouldn’t be as much of a performance problem, because they are very lightweight, it is slightly wasteful only.

    But, the bad thing, is with these threads switching and C++ exceptions used to represent Python exceptions, no combination of MSVC options seems to carry the day and keep the exception in the current thread. They are caught in the wrong thread, and make generators misbehave, crash.

    This is the only thing that holds back proper MSVC support at this time, and it has been like this for a while. With MinGW, the issue does not exist, but MinGW is a stranger to many, and MSVC will be more efficient code generation, so we would like to have that.

    So what it takes is somebody familiar with Windows and its ABI, esp. register usage to write code that swaps the registers around, so we can have multiple C stacks without threads for it too. This may involve messing around with exception jump back pointers as well.

    It needs somebody who can handle this and does it for Nuitka, and then it would be well supported. It may involve writing some assembler code. The job is also very well contained, but also requires very specific knowledge, so please join me here. If you think you can do this, do it.

  • Windows 64 bit

    I have no access to Win64. I bought many Windows versions, but not the Win64 variants so far. I understand that there are CPython builds for it, and probably a MinGW matching it, as well as a matching newer MSVC, that may work better for C++ exceptions than the one CPython 2.x is tied to.

    Doing that, you would mostly only have to play around with SingleExe.scons, which abstracts the details of it all. One issue you will encounter is that Scons needs a Python2, and other small things. This is mostly only about porting Nuitka, and could be done by anybody with access to Win64 and willing to fiddle around a bit.

So these are 3 different ways you can help Nuitka. Creating the Python compiler is a huge effort. And if you help it, we will sooner arrive at its goals. Join the Nuitka mailing list (since closed) or contact me directly if you choose to help with any of these issues.

Wait, actually there is another way you can help. Please spread this news to people that you believe might be willing to help. And allow me to plug this, I am doing Nuitka in my spare time. If you feel, you cannot help, but still would like to support it, you can still make donations to allow me to travel to conferences and spend more time on it myself.

Anyway, it would be great if these 3 things got sorted out. Come and join me for this grand vision of the Python compiler.

Yours,
Kay