The wasm*-unknown-unknown targets are not supported by default, you may need to enable the "js" feature

⚓ Rust    📅 2025-06-28    👤 surdeus    👁️ 8      

surdeus

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Hi

I am trying to get lox-wasm running to contribute to the Tor Project.

I followed the README.md and executed wasm-pack build --target web but I get the following errors:

rror: the wasm*-unknown-unknown targets are not supported by default, you may need to enable the "js" feature. For more information see: https://docs.rs/getrandom/#webassembly-support
   --> /Users/niel/.cargo/registry/src/index.crates.io-6f17d22bba15001f/getrandom-0.2.16/src/lib.rs:346:9
    |
346 | /         compile_error!("the wasm*-unknown-unknown targets are not supported by \
347 | |                         default, you may need to enable the \"js\" feature. \
348 | |                         For more information see: \
349 | |                         https://docs.rs/getrandom/#webassembly-support");
    | |________________________________________________________________________^

   Compiling wasm-bindgen v0.2.100
error[E0433]: failed to resolve: use of undeclared crate or module `imp`
   --> /Users/niel/.cargo/registry/src/index.crates.io-6f17d22bba15001f/getrandom-0.2.16/src/lib.rs:402:9
    |
402 |         imp::getrandom_inner(dest)?;
    |         ^^^ use of undeclared crate or module `imp`

For more information about this error, try `rustc --explain E0433`.
error: could not compile `getrandom` (lib) due to 2 previous errors

But wasm_js is set for get_random in the Cargo.toml.

It compiles with cargo build --lib --release but that of course does not generate the correct WASM files IG.

My rustc version:

rustc 1.83.0 (90b35a623 2024-11-26)
binary: rustc
commit-hash: 90b35a6239c3d8bdabc530a6a0816f7ff89a0aaf
commit-date: 2024-11-26
host: aarch64-apple-darwin
release: 1.83.0
LLVM version: 19.1.1

What am I missing?

Edit: Also weird, the Cargo.toml specifies v0.3.0 for get_random, but the error output seems to be working with v0.2.16 :thinking:

├── getrandom v0.3.3
│   │   │   │   │   └── getrandom v0.2.16

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