[Bug]: build stuck

[T9-Forever]

System Info

System:
OS: macOS 15.6.1
CPU: (10) arm64 Apple M1 Pro
Memory: 229.77 MB / 16.00 GB
Shell: 5.9 - /bin/zsh
Binaries:
Node: 18.16.0 - /Users/edson.lin/.nvm/versions/node/v18.16.0/bin/node
Yarn: 1.22.22 - /Users/edson.lin/.nvm/versions/node/v18.16.0/bin/yarn
npm: 9.5.1 - /Users/edson.lin/.nvm/versions/node/v18.16.0/bin/npm
pnpm: 10.20.0 - /Users/edson.lin/.nvm/versions/node/v18.16.0/bin/pnpm
Browsers:
Chrome: 142.0.7444.60
Safari: 18.6
npmPackages:
@rspack/cli: ^1.6.0 => 1.6.0
@rspack/core: ^1.6.0 => 1.6.0
@rspack/plugin-react-refresh: ^1.5.2 => 1.5.2

Details

If a worker includes styles (sass-loader + modern-compiler + sass-embedded), it causes the build to hang and the CI never finishes.

Reproduce link

https://github.com/T9-Forever/rspack-stuck

Reproduce Steps

1. Run npm run build
2. see console

[hardfist]

it's actually same issue as webpack/sass-loader#1244 which behaves same as webpack + worker-loader, so the real problem is

• worker-loader doesn't call childCompiler.close()
• sass-loader use shutdown hooks which may not be called for child-compiler

So we may have following solutions

• call childCompiler.close in worker-loader so it can successfully call shutdown hooks
• sass-loader use done hooks which may be more accurate than shutdown hook

cc @alexander-akait, what's your suggestion?

[alexander-akait]

@hardfist

call childCompiler.close in worker-loader so it can successfully call shutdown hooks

it is the right solution, but worker-loader is deprecated at all and should not be used, more likely doesn't have compatibility with webpack@5/rspack...

sass-loader use done hooks which may be more accurate than shutdown hook

shutdown is the place where we should shutdown everything - extra compilers, caches, active connections, etc, done is more about compilation was done, where you need to handle something from stats/reports/etc