What does composer error mean?

Question

macOS

Can't install any Laravel add-ons. After entering commands like this composer require barryvdh/laravel-debugbarin the terminal, an error appears

[Symfony\Component\Process\Exception\RuntimeException]
  The process has been signaled with signal "5".

After several attempts to remove and reinstall Composer on the system (Mac Os X El Capitan), the situation did not change.
Google didn't help. What to do?

Answer 1

Hooray! Found. I'll leave it for the rest

$brew install svn
$brew link --overwrite subversion

Answer 2

Google did not help, we try Yandex
Although Google is the norm: tyts
In general, you would supplement the question with the full text of the error.