Compiler version
a3f3ae3
Minimized code
Start the REPL and do the following:
scala> :settings -Xrepl-disable-display
scala> System.exit(123)
scala>
Output
The expression is not evaluated and the E part of REPL is missing (instead of R).
Expectation
The flag says that we disable rendering, not evaluation.
Running the REPL without the adding the flag will indeed evaluate the expression and kill the REPL with exit code 123 in this example.