SWC Transpilation/Minification generates wrong code

[milap1296]

Link to the code that reproduces this issue

https://github.com/milap1296/swc-minify-issue

To Reproduce

I am using crypto-js as a dependency and while performing swc-minification it generates a wrong code.

Works correctly in dev environment

1. yarn install
2. yarn dev
3. No client exception

Works incorrectly in production with swcMinify:true

1. yarn install
2. yarn build
3. yarn start
4. You will be able to see client exception like below
   
   Error might be because of this Math = Math assignment in the minified code!
   

Works incorrectly in production with swcMinify:false

1. yarn install
2. yarn build
3. yarn start
4. You will be able to see same client exception as point:2

Current vs. Expected behavior

It should not throw exception in production and should work like it is in development mode.

Verify canary release

• I verified that the issue exists in the latest Next.js canary release

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 23.0.0: Fri Sep 15 14:41:43 PDT 2023; root:xnu-10002.1.13~1/RELEASE_ARM64_T6000
Binaries:
  Node: 18.18.2
  npm: 9.8.1
  Yarn: 1.22.19
  pnpm: N/A
Relevant Packages:
  next: 14.0.2
  eslint-config-next: 14.0.2
  react: 18.2.0
  react-dom: 18.2.0
  typescript: N/A
Next.js Config: {
    swcMinify: true,
    reactStrictMode: true
}

Which area(s) are affected? (Select all that apply)

SWC transforms

Additional context

No response

[heggland]

Confirming this bug on nextjs ^14.0.3

I use crypto-js to generate a md5 hash for API call and randomized filename on a form submit function.

link to last error - https://legacy.reactjs.org/docs/error-decoder.html/?invariant=423

[m19]

I think I am getting a similar issue because of the transpilation/minification, although I am not using crypto-js.

On 14.0.3 I'm getting this on a specific page, only in production:

Uncaught SyntaxError: Identifier 'Audio' has already been declared (at 9436-65c1526a112a4e04.js:4:22913)

On dev mode, it works fine.

If I downgrade back to 14.0.1 it works fine in both dev and prod. So I think it's related to this issue.

[kdy1]

Closing as fixed by #58517
You can use canary to get it fixed

[milap1296]

Closing as fixed by #58517 You can use canary to get it fixed

@kdy1 I am still able to reproduce the issue with next@14.0.4-canary.39, could you please check again ?

[github-actions]

This closed issue has been automatically locked because it had no new activity for 2 weeks. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.