Any plans for wasm64 support?

[tudor]

Are there any plans to support 64-bit builds?

It looks to me like wasm64 (also known as "memory64") uses a LP64 model (int is 32 bits, long, long long, and pointers are 64 bits), which is the same as the memory model on 64-bit Unix-y platforms (not Windows, where long is still 32 bits even on x86_64).

[sunfishcode]

Yes; the main work right now is happening in upstream LLVM (eg. here).

There will also need to be some amount of work to port wasi-libc. All the code in wasi-libc is written with a wasm64 target in mind. We'll need a 64-bit version of the WASI APIs as well, and the code for that is also all written with a wasm64 target in mind. So in theory this should be a straightforward process.

[tudor]

Exciting!

I have a strong vested interest in seeing WASM succeed as a server-side plugin (and write-once, run-anywhere code distribution) platform. There are a few missing pieces:

• 64-bit support
• threads
• sockets
• stack unwinding / exception handling

but it seems that all 4 areas are seeing a lot of active work, which means 2022 will be an exciting year for WASM.

[TimWhiting]

It's been a few years and the clang link seems to have been resolved. Any updates?

[abrown]

I don't see anyone working on this too closely at the moment: are you interested in adding support for wasm64-wasi?

[TimWhiting]

If it isn't a bunch of work. Are there assumptions being made that make this a big effort, or is it a simple change?

[sbc100]

I would hope its not too much work. I imagine most things will just work. The biggest change is likely that would we would need to start shipping all of our pre-built libraries in wsam64 variants.

[mh4ck-Thales]

I'd be interested in seeing wasi-sdk support wasm64, if everything is ready for it. Seems that the first thing to do would be to make wasi-libc support wasm64 ; should we open an issue there ?

[abrown]

There's been some work already on that in WebAssembly/wasi-libc#444 but there are concerns about how that is implemented so I think some discussion is needed. @loganek is also interested in making this happen and has added an agenda item to the WASI subgroup meeting to have that discussion: WebAssembly/meetings#1479. Can you join that?