WASM support broken due to incompatible dependencies

[jozanza]

Following instructions at https://jolt.a16zcrypto.com/usage/wasm_support.html, I was unable to compile my project to wasm.

Steps to reproduce

1. Make a new project (jolt new foo --wasm)
2. Ensure fib(n: 32) -> u128 in guest/src/lib.rs has #[jolt::provable(wasm)]
3. Build the project jolt build-wasm

Expected result
I expect a wasm bin to be compiled and output to target/wasm32-unknown-unknown/release as well as an index.html and a pkg dir with some wasm-pack stuff.

Actual result
index.html is created, but wasm compilation fails as it encounters some nix modules within the tracing-profile dependency:

error[E0433]: failed to resolve: could not find `sys` in `nix`
 --> ~/.cargo/git/checkouts/tracing-profile-ea11638690e1685c/6d986ca/src/data/span_metadata.rs:4:10
  |
4 | use nix::sys::time::TimeSpec;
  |          ^^^ could not find `sys` in `nix`

error[E0433]: failed to resolve: could not find `sys` in `nix`
 --> ~/.cargo/git/checkouts/tracing-profile-ea11638690e1685c/6d986ca/src/layers/csv.rs:1:10
  |
1 | use nix::sys::time::TimeValLike;
  |          ^^^ could not find `sys` in `nix`

error[E0432]: unresolved import `nix::time`
 --> ~/.cargo/git/checkouts/tracing-profile-ea11638690e1685c/6d986ca/src/layers/csv.rs:2:10
  |
2 | use nix::time::{clock_gettime, ClockId};
  |          ^^^^ could not find `time` in `nix`

cargo tree -i tracing profile reveals the tree:

cargo tree -i tracing-profile              
tracing-profile v0.8.0 (https://gitlab.com/IrreducibleOSS/tracing-profile.git?branch=main#6d986ca1)
└── binius_utils v0.1.0 (https://gitlab.com/UlvetannaOSS/binius#a0a71393)
    └── binius_field v0.1.0 (https://gitlab.com/UlvetannaOSS/binius#a0a71393)
        └── jolt-core v0.1.0 (https://github.com/a16z/jolt#e08998e8)
            └── jolt-sdk v0.1.0 (https://github.com/a16z/jolt#e08998e8)
                ├── guest v0.1.0 (~/foo/guest)
                │   └── foo v0.1.0 (~/foo)
                └── foo v0.1.0 (~/foo)

[moodlezoup]

Hmm does #462 fix the issue?

[myceliaspy]

hey! I'm getting this same issue, which is unrelated to my pr. that one was introduced to fix an issue originally mentioned here #448. I think the problem with this one is that, since nix uses sys related functions, it's definitely not no_std – which I think is a wasm requirements – so it can't be compiled. not sure what the fix can be, as I tried writing my own no_std compatible equivalents and it made me want to die. Will look forward to the progress here.

[jozanza]

@myceliaspy no_std isn't required for wasm. Typically, the solution is just making sure code paths that use native-only crates/modules don't get imported. Just based on cursory observations, it looks like nix::sys is really just being used for some profiling that most likely wouldn't make sense in a wasm env anyways or at least wouldn't be critical to generate proofs, etc.

[moodlezoup]

hmm I guess we could just slap a #[cfg(not(target_arch = "wasm32"))] on all the Binius stuff... we'll need an upstream fix eventually though if we want to support Binius+wasm

[sagar-a16z]

filed https://gitlab.com/IrreducibleOSS/binius/-/issues/5 to track the upstream fix and #483 to unblock wasm for now