What does it mean to get "Compiler internal error" but then for the compile to proceed?

When I compile, I first get the error:

Error:Compiler internal error. Process terminated with exit code 1

But then compile continuous, I get some more errors (maybe) and then get the three Information messages that get inserted /before/ the internal error

Information:Compilation completed with 101 errors and 0 warnings

Information:101 errors

Information:0 warnings

Error:Compiler internal error. Process terminated with exit code 1

E:\si\insight.liftui\servers\si-utilization\src\test\scala\systeminsights\utilization\parts\OnStateWhileProducingPartsRuleSpec.scala

    Error:Error:line (15)error: not found: type OnStateWhileProducingPartsRule

val rule = new OnStateWhileProducingPartsRule[Program](

E:\si\insight.liftui\servers\si-utilization\src\test\scala\systeminsights\utilization\parts\AbstractPartsRuleSpec.scala

    Error:Error:line (18)error: not found: type PartsUpdating

The above happens when doing a full compile of a module. When I compile just one file I only get the internal error.