False positive for TS2448 "use before declaration" in 3.8.3 --target esnext

[Jessidhia]

TypeScript Version: 3.8.3

Search Terms:
TS2448, use before declaration

Code

const a = () => b()
const b = () => null
a()

Expected behavior:
No errors

Actual behavior:

Block-scoped variable 'b' used before its declaration.

Playground Link: Playground Link

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This error seems to only happen, at least in the playground, when the target is set to ESNext. If it's set to, say, ES2020, the error goes away... in tsservice; it still happens in tsc.

This seems to have been introduced between 3.8.0-beta (builds) and 3.8.1-rc (errors).

[RyanCavanaugh]

@Jessidhia do you need a patch build for this?

[Jessidhia]

Probably not, I can just move to the nightly or 3.9.0 when it's fixed 🤔