Symfony version(s) affected: 4.1 (maybe 3.4 as well)

Description
The error happens in AnalyzeServiceReferencesPass.php(119) and seems to happen as soon as a service looses some reference. Nested call involved with the service :)

How to reproduce

see https://github.com/ro0NL/sf-di/commits/master

Additional context

not sure if i relied on a bug actually =/

cc @nicolas-grekas