rustwasm
wasm-opt fail with [parse exception: invalid code after misc prefix: 17 (at 0:61491)]
🐛 Bug description
Our build was working up to rust 1.81.0. With Rustc 1.82.0, I am getting an error with wasm-opt.
🤔 Expected Behavior
wasm-opt should work with rustc 1.82.0
👟 Steps to reproduce
wasm-pack build --release --no-typescript --target nodejs --out-dir ../_build/wasm/node
[INFO]: Checking for the Wasm target...
info: downloading component 'rust-std' for 'wasm32-unknown-unknown'
info: installing component 'rust-std' for 'wasm32-unknown-unknown'
18.7 MiB / 18.7 MiB (100 %) 13.8 MiB/s in 1s ETA: 0s
[INFO]: Compiling to Wasm...
Finished `release` profile [optimized] target(s) in 0.08s
[INFO]: Installing wasm-bindgen...
[INFO]: found wasm-opt at "/usr/bin/wasm-opt"
[INFO]: Optimizing wasm binaries with `wasm-opt`...
[parse exception: invalid code after misc prefix: 17 (at 0:61491)]
Fatal: error parsing wasm
Error: failed to execute `wasm-opt`: exited with exit status: 1
full command: "/usr/bin/wasm-opt" "/home/ubuntu/symbol/sdk/javascript/_build/wasm/node/symbol_crypto_wasm_bg.wasm" "-o" "/home/ubuntu/symbol/sdk/javascript/_build/wasm/node/symbol_crypto_wasm_bg.wasm-opt.wasm" "-O"
To disable `wasm-opt`, add `wasm-opt = false` to your package metadata in your `Cargo.toml`.
Caused by: failed to execute `wasm-opt`: exited with exit status: 1
full command: "/usr/bin/wasm-opt" "/home/ubuntu/symbol/sdk/javascript/_build/wasm/node/symbol_crypto_wasm_bg.wasm" "-o" "/home/ubuntu/symbol/sdk/javascript/_build/wasm/node/symbol_crypto_wasm_bg.wasm-opt.wasm" "-O"
To disable `wasm-opt`, add `wasm-opt = false` to your package metadata in your `Cargo.toml`.
🌍 Your environment
Include the relevant details of your environment. Ubuntu 24.04(it works on MacOs) wasm-pack version: wasm-pack -V wasm-pack 0.13.1
rustc version: rustc -V rustc 1.82.0 (f6e511eec 2024-10-15)
The code is here - https://github.com/symbol/symbol/tree/dev/sdk/javascript/wasm
When wasm-bindgen 0.2.94-95 sees the wasm target-features metadata emitted by rustc 1.82.0, it enables additional webassembly features on its output (bulk memory instructions) that can cause issues with downstream tools like wasm-opt. This will be fixed in the next release of wasm-bindgen. Until then, workarounds include adding --enable-bulk-memory to the wasm-opt commandline (if your runtime is compatible with bulk-memory instructions), not using wasm-opt at all, or downgrading to rust 1.81 or to wasm-bindgen 0.2.93.
Related discussions: https://github.com/rustwasm/wasm-bindgen/issues/4250 https://github.com/rustwasm/wasm-bindgen/issues/4211 https://github.com/rust-lang/rust/issues/132620 https://github.com/trunk-rs/trunk/issues/904
I fixed this by upgrading wasm-pack to the latest version.
It's a bit annoying because it doesn't auto update. It's not a js library or a rust crate or whatever. I had to install it from the site: https://rustwasm.github.io/wasm-pack/installer/
Also experiencing compilation failures when following the MDN docs at https://developer.mozilla.org/en-US/docs/WebAssembly/Guides/Rust_to_Wasm
It seems a similar case was reported with Rust 1.87. Is there anything that can be done on the wasm-pack side to address this?
https://github.com/rust-lang/rust/issues/141048
In our case, we worked around this by putting
[package.metadata.wasm-pack.profile.release]
wasm-opt = ["--enable-bulk-memory", "--enable-nontrapping-float-to-int"]
in our Cargo.toml.
Note from the future: the default for this is ["-O"], so you probably want ["-O", "--enable-bulk-memory", "--enable-nontrapping-float-to-int"].
I am seeing this problem again with Rustc 1.87.0
1.87.0-aarch64-unknown-linux-gnu installed - rustc 1.87.0 (17067e9ac 2025-05-09)
info: default toolchain set to '1.87.0-aarch64-unknown-linux-gnu'
info: checking for self-update
+ wasm-pack build --release --no-typescript --target nodejs --out-dir ../_build/wasm/node
[INFO]: Checking for the Wasm target...
info: downloading component 'rust-std' for 'wasm32-unknown-unknown'
info: installing component 'rust-std' for 'wasm32-unknown-unknown'
[INFO]: Compiling to Wasm...
Compiling unicode-ident v1.0.18
Compiling proc-macro2 v1.0.95
Compiling version_check v0.9.5
Compiling wasm-bindgen-shared v0.2.100
Compiling typenum v1.18.0
Compiling bumpalo v3.17.0
Compiling semver v1.0.26
Compiling log v0.4.27
Compiling cfg-if v1.0.0
Compiling rustversion v1.0.21
Compiling wasm-bindgen v0.2.100
Compiling once_cell v1.21.3
Compiling serde v1.0.219
Compiling keccak v0.1.5
Compiling zeroize v1.8.1
Compiling subtle v2.6.1
Compiling generic-array v0.14.7
Compiling rustc_version v0.4.1
Compiling curve25519-dalek v4.1.3
Compiling quote v1.0.40
Compiling syn v2.0.101
Compiling block-buffer v0.10.4
Compiling crypto-common v0.1.6
Compiling digest v0.10.7
Compiling sha2 v0.10.9
Compiling sha3 v0.10.8
Compiling hex v0.4.3
Compiling wasm-bindgen-backend v0.2.100
Compiling wasm-bindgen-macro-support v0.2.100
Compiling wasm-bindgen-macro v0.2.100
Compiling console_error_panic_hook v0.1.7
Compiling js-sys v0.3.77
Compiling symbol-crypto-wasm v0.1.0 (/symbol/sdk/javascript/wasm)
Finished `release` profile [optimized] target(s) in 4.00s
[INFO]: Installing wasm-bindgen...
[INFO]: found wasm-opt at "/usr/bin/wasm-opt"
[INFO]: Optimizing wasm binaries with `wasm-opt`...
[parse exception: invalid code after misc prefix: 17 (at 0:62712)]
Fatal: error parsing wasm
Error: failed to execute `wasm-opt`: exited with exit status: 1
full command: "/usr/bin/wasm-opt" "/symbol/sdk/javascript/_build/wasm/node/symbol_crypto_wasm_bg.wasm" "-o" "/symbol/sdk/javascript/_build/wasm/node/symbol_crypto_wasm_bg.wasm-opt.wasm" "-O"
To disable `wasm-opt`, add `wasm-opt = false` to your package metadata in your `Cargo.toml`.
Caused by: failed to execute `wasm-opt`: exited with exit status: 1
full command: "/usr/bin/wasm-opt" "/symbol/sdk/javascript/_build/wasm/node/symbol_crypto_wasm_bg.wasm" "-o" "/symbol/sdk/javascript/_build/wasm/node/symbol_crypto_wasm_bg.wasm-opt.wasm" "-O"
To disable `wasm-opt`, add `wasm-opt = false` to your package metadata in your `Cargo.toml`.
Rust 1.87.0 moved to LLVM 20, which enabled more webassembly features by default.
wasm-opt needs additional commandline flags to enable the same webassembly features, or it will fail with this error. See earlier comments for some flags to try.
Rust 1.87.0 moved to LLVM 20, which enabled more webassembly features by default.
wasm-optneeds additional commandline flags to enable the same webassembly features, or it will fail with this error. See earlier comments for some flags to try.
Yes, Thanks. I have tried the flags above, but it does not help. I forgot to mention that the build only fails on Ubuntu ARM. So, Ubuntu AMD64/Windows AMD64 builds are correct.
@Wayonb consider checking what version of wasm-opt you are running at /usr/bin/wasm-opt. I saw a similar issue on Rustc 1.87.0 with version 116 and it was fixed by upgrading to version 117.
