[Compiler Bug]: Compiler introduces unnecessary breaks that skips its own memoization

[refparo]

What kind of issue is this?

• React Compiler core (the JS output is incorrect, or your app works incorrectly after optimization)
• babel-plugin-react-compiler (build issue installing or using the Babel plugin)
• eslint-plugin-react-compiler (build issue installing or using the eslint plugin)
• react-compiler-healthcheck (build issue installing or using the healthcheck script)

Link to repro

https://playground.react.dev/#N4Igzg9grgTgxgUxALhAgHgBwjALgAgBMEAzAQygBsCSoA7OXASwjvwFkBPAQU0wApg+XJ0wJ8AXwCU+YAB02+OKzAEAtgjUQmALwSF8AXnxQwCdpoj9+MwwD5ZC-M6UqCANzKUo44xjF0YEzuCDYA3E4uTCT4-CJiRobGcuAAFji4APq4CDBqKTLyii74MAi4sGye3ggRxZL4CJRmjvXO1T4AdGpQuGQ54ZElZRUwVV4+dSUSkRIANPgA2vEIALpSU6XllfgAPITBdgASTZQQ+ADqOJQGwBpauvoSuwD0B+52dTN0IBJAA

(Update: made the repro shorter and more generic)

Repro steps

1. See the playground link.
2. Look at the two breaks the compiler introduced in the output. The memoization is skipped by the two breaks, making the result of useMemo always new in each render.

How often does this bug happen?

Every time

What version of React are you using?

Both 18.3.1 and the version used by Playground

What version of React Compiler are you using?

Both 19.1.0-rc.2 and the version used by Playground

[josephsavona]

Thanks for posting, that’s definitely a bug. We’ll take a look!

[Shonferns004]

Hello! 👋 I came across issue and would love to work on this. I’ve set up the repo locally and started digging into it.

Just wanted to check in before starting — is anyone already working on this? If not, I’d love to take it up.

Thanks!