compinit error when IFS is \n

["Avid Seeker" <avidseeker@xxxxxxxxxxx>]

~/.zshrc:

```
	. ~/.local/share/zsh/plugged/zsh-autosuggestions/zsh-autosuggestions.zsh

	IFS=$'\n'

	autoload -Uz compinit; compinit
```

results in

```
(eval):zle:1: not enough arguments for -C
_main_complete:compset:94: can only be called from completion function
_setup:37: compstate: assignment to invalid subscript range
(eval):zle:1: not enough arguments for -C
...
```

Uncomment any of the three lines in ~/.zshrc and the problem is gone.

```
$ZSH_VERSION is 5.9
```


zsh-autosuggestions open issue: https://github.com/zsh-users/zsh-autosuggestions/issues/825

Original discussion: https://github.com/gokcehan/lf/discussions/1947