Unable to compile the raytrace-parallel example

[AnneKitsune]

Describe the Bug

@alexcrichton
The example will not compile.

Steps to Reproduce

rustup update
rustup target add wasm32-unknown-unknown
git clone https://github.com/rustwasm/wasm-bindgen/
cd wasm-bindgen/examples/raytrace-parallel
./build.sh

Expected Behavior

The example compiles and everything works.

Actual Behavior

Error:

+ RUSTFLAGS='-C target-feature=+atomics,+bulk-memory'
+ cargo build --target wasm32-unknown-unknown --release -Z build-std
warning: unused label
   --> crates/webidl/src/util.rs:427:9
    |
427 |         'outer: for signature in data.signatures.iter() {
    |         ^^^^^^
    |
    = note: `#[warn(unused_labels)]` on by default

   Compiling raytrace-parallel v0.1.0 (/tmp/wasm-bindgen/examples/raytrace-parallel)
error: duplicate lang item in crate `core`: `bool`.
  |
  = note: first defined in crate `core` (which `std` depends on).

error: duplicate lang item in crate `core`: `char`.
  |
  = note: first defined in crate `core` (which `std` depends on).

error: duplicate lang item in crate `core`: `str`.
  |
  = note: first defined in crate `core` (which `std` depends on).

...100 more

Additional Context

Similar issue? rust-lang/cargo#7359

Thanks for your time :)

[alexcrichton]

Thanks for the report! I think this should be fixed now.