Syntax highlighting broken in Emacs 30.1

[jlandahl]

What happened?

1. I compiled Emacs 30.1 locally with my usual configuration flags (nothing fancy)
2. I started up Emacs with the Doom config I’ve been using for a year or two
3. I noticed immediately that there is no syntax highlighting for Rust code, just white text on a dark background
4. I then opened some of the .el files in ~/.config/doom and saw that the same problem is happening for elisp files
5. Org files somehow do have correct syntax highlighting

Update: Cargo.toml is shown correctly, and warnings are being highlighted in Rust code as expected, but no syntax highlighting, and also there are no completions as I type (e.g. typing use serde:: should show some completions, but doesn’t). See second screen shot.

What did you expect to happen?

I expected Emacs 30.1 with an existing Doom setup to look the same as it did the day before with Emacs 29.4.

Steps to reproduce

1. Run Emacs 30.1
2. See code with not syntax highlighting

System information

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