4 ms·

your intel CPU allows you to iterate through the stack and jump to a location in the heap though (as long as you don't mark the page NX). These features are use

your intel CPU allows you to iterate through the stack and jump to a location in the heap though (as long as you don't mark the page NX). These features are used by most gc and jit implementations respectively. wasm requires all functions to be specified at module creation time and gives no access to the stack.

pjmlp 7y ago
There are plenty of GC algorithms to chose from, and several examples how to implement them in WebAssembly already. https://github.com/appcypher/awesome-wasm-langs/blob/master/README.md https://github.com/appcypher/awesome-wasm-langs/blob/master/... No need to get everything served on a plate.
- monocasa 7y ago
  Those have suboptimal GC implementations because of the lack of primitives to do better. Some just straight up use reference counting and leak anything with circular references.
  - pjmlp 7y ago
    So what? Yes some have buggy implementations, others could do better, yet they exist. I rather have a half working bicycle that takes me to town than none at all.
    - monocasa 7y ago
      What is a "half working bicycle that takes me to town". Like by definition it fulfills it purpose. A garbage collector that breaks down on circular references is crazy town for real work. Like there's even AI Lab Koan about that specifically. http://catb.org/jargon/html/koans.html http://catb.org/jargon/html/koans.html A better example would be a bicycle without the front wheel. Yeah, if you're real good and real careful you can probably treat it as a unicycle and get to where you're going, but you'd be real pissed if someone sold it to you as a working bicycle, no?
      - pjmlp 7y ago
        Not all GC enabled languages that currently target WebAssembly are buggy as you make it to be. PNaCL also did not have direct GC support, yet it got released with working OCaml support.
        monocasa 7y ago
        Did anyone actually use that OCaml support? Like a single production application?
        pjmlp 7y ago
        Maybe yes, maybe no. Enjoying moving goalposts?
        monocasa 7y ago
        It's not moving goalposts. If nobody is using it, not even the developers who put in the effort to make it work, it's a pretty good sign it's not a production ready solution. Like "technically works enough for a demo" isn't what I'd call full support.
        pjmlp 7y ago
        The whole point of this thread was that implementing a GC is possible with what WebAssembly provides today, no need to wait for an API that might never come. Yes there are bugs in some implementations and others could have been better done, it happens. Discussing technicalities of who is using what in production is moving goalposts. Not a big fan of having lost PNaCL in favour of WebAssembly craziness, but that is what we have to work with, GC might come in 5 years time or even never, who knows. What I know is that despite the flaws, many developers are eager to implement something with what we have now and kudos to them for trying it out. “They did not know it was impossible so they did it” ― Mark Twain
        monocasa 7y ago

pjmlp 7y ago

There are plenty of GC algorithms to chose from, and several examples how to implement them in WebAssembly already. https://github.com/appcypher/awesome-wasm-langs/blob/master/README.md https://github.com/appcypher/awesome-wasm-langs/blob/master/... No need to get everything served on a plate.

monocasa 7y ago
Those have suboptimal GC implementations because of the lack of primitives to do better. Some just straight up use reference counting and leak anything with circular references.
- pjmlp 7y ago
  So what? Yes some have buggy implementations, others could do better, yet they exist. I rather have a half working bicycle that takes me to town than none at all.
  - monocasa 7y ago
    What is a "half working bicycle that takes me to town". Like by definition it fulfills it purpose. A garbage collector that breaks down on circular references is crazy town for real work. Like there's even AI Lab Koan about that specifically. http://catb.org/jargon/html/koans.html http://catb.org/jargon/html/koans.html A better example would be a bicycle without the front wheel. Yeah, if you're real good and real careful you can probably treat it as a unicycle and get to where you're going, but you'd be real pissed if someone sold it to you as a working bicycle, no?
    - pjmlp 7y ago
      Not all GC enabled languages that currently target WebAssembly are buggy as you make it to be. PNaCL also did not have direct GC support, yet it got released with working OCaml support.
      - monocasa 7y ago
        Did anyone actually use that OCaml support? Like a single production application?
        pjmlp 7y ago
        Maybe yes, maybe no. Enjoying moving goalposts?
        monocasa 7y ago
        It's not moving goalposts. If nobody is using it, not even the developers who put in the effort to make it work, it's a pretty good sign it's not a production ready solution. Like "technically works enough for a demo" isn't what I'd call full support.
        pjmlp 7y ago
        The whole point of this thread was that implementing a GC is possible with what WebAssembly provides today, no need to wait for an API that might never come. Yes there are bugs in some implementations and others could have been better done, it happens. Discussing technicalities of who is using what in production is moving goalposts. Not a big fan of having lost PNaCL in favour of WebAssembly craziness, but that is what we have to work with, GC might come in 5 years time or even never, who knows. What I know is that despite the flaws, many developers are eager to implement something with what we have now and kudos to them for trying it out. “They did not know it was impossible so they did it” ― Mark Twain
        monocasa 7y ago