Completions for bash 4 never finish loading

I've installed bash 4 and bash-completions@2 with Homebrew following all kinds of guides I found online. However, when I open a new terminal it just hangs. By placing some echos in my .bash_profile it seems to be hanging on loading the completions.

My .bash_profile:

# Import all files
for DOTFILE in ~/.{aliases,env,functions,path,prompt,extra}
do
    [ -r "$DOTFILE" ] && [ -f "$DOTFILE" ] && source "$DOTFILE"
done

unset DOTFILE;

echo $BASH_VERSION
printf "Loading bash completions..."
if [ -f /usr/local/share/bash-completion/bash_completion ]; then
    . /usr/local/share/bash-completion/bash_completion
fi
printf "done!"

if [ -f "$(brew --prefix)/opt/bash-git-prompt/share/gitprompt.sh" ]; then
    GIT_PROMPT_THEME=Default
    source "$(brew --prefix)/opt/bash-git-prompt/share/gitprompt.sh"
fi

(the DOTFILE stuff is loading my dotfiles)

When I open a new terminal with the above .bash_profile I get this output:

Last login: Fri Jun 23 10:43:12 on ttys001
4.4.12(1)-release
Loading bash completions...

Running brew doctor doesn't say anything about bash completions.

What can I do to get this working?

UPDATE
There were a bunch of rustc processes taking up a lot of CPU. Most likely related.