They plan to build a standardised garbage collector at a later stage so support other languages that require this so they can compile straight to web assembly.
2. If web-assembly incorporates a GC, then it will become needlessly complicated.
3. Unnecessary complication in web-assembly means also unnecessary room for security flaws.
(4. What good is a web assembly if you can't implement an efficient garbage collector in it?)
What is wrong with open-sourcing GC code as independent libraries, so that web-app makers or (more likely) compiler developers (with less skill/time) can use them at will?
> the issue with #4 is that you would need threads w/ shared memory
But this is exactly what we need for other applications as well. For example, how would you send a large immutable data-structure across two threads? By copying it? Of course not, you just share pointers, meaning that the address space should be shared. If this is not possible, then that is a major flaw in WASM's design.
I think you have the impression that incorporating a GC into WASM makes life easier. But it doesn't. It is the exact opposite. WASM should be as simple as possible.
There's nothing that would prevent writing your own GC if you felt the need.
I don't think it is. What I would like to see is that compiler writers keep control over their GC.
> Waiting until WASM has the ability to do threaded memory management at the same level as the existing GCs and have them rewritten (or refactored) for it may be too long.
I don't see the big problems. We already have assembly without GCs, and it is called VirtualBox (or VMWare). Why not use something like that? (Yes, there are still some security issues, but these can be solved much easier than when the hairy GC code becomes part of the game).
In other words, let's first create a real assembly language with a simple but adequate instruction set, and make it secure. This is what I would call "assembly language" anyway.
Since WebAsm is still Functional languages would still have the freedom to implement their own more efficient GC (avoid the write barrier in a lot of cases, scan only the young heap most of the time, etc).
This sounds a lot like "640k ought to be enough for everyone" :)
Also, it only addressed my first point.
There's nothing stopping you from implementing your own GC. But having a standardized GC (the JS engine's GC) means much simpler interop between wasm languages.