Error: unrecognized switch '--DRT-oncycle=print' => where is switch defined?

[Timothee Cour via Digitalmars-d-learn]

Getting this:

```
Deprecation 16211 warning:
A cycle has been detected in your program that was undetected prior to DMD
2.072. This program will continue, but will not operate when using DMD 2.073
to compile. Use runtime option --DRT-oncycle=print to see the cycle details.
```

Where is ` --DRT-oncycle=print` defined? can't find it even on DMD64 D
Compiler v2.075.0-devel-c3ddfaa-dirty

And adding the switch results in:
Error: unrecognized switch '--DRT-oncycle=print'