Make errors are not swept under the carpet

Typer#ensureReported's comment outlines an example where errors
could go unreported, resulting in error trees after typer without
any reported error messages. This commit makes sure that at least
one error is reported if a tree node has an error type.

Fixes #1802.

1 files changed, 2 insertions, 2 deletions

diff --git a/compiler/src/dotty/tools/backend/jvm/scalaPrimitives.scala b/compiler/src/dotty/tools/backend/jvm/scalaPrimitives.scala
index eb4da5400..89831e56b 100644
--- a/compiler/src/dotty/tools/backend/jvm/scalaPrimitives.scala
+++ b/compiler/src/dotty/tools/backend/jvm/scalaPrimitives.scala
@@ -12,7 +12,7 @@ import dotty.tools.dotc.ast.tpd._
 import dotty.tools.dotc.core.Names.TermName
 import dotty.tools.dotc.core.StdNames
 import dotty.tools.dotc.core.StdNames._
-import dotty.tools.dotc.core.Types.{JavaArrayType, ErrorType, Type}
+import dotty.tools.dotc.core.Types.{JavaArrayType, UnspecifiedErrorType, Type}
 
 import scala.collection.{ mutable, immutable }
 
@@ -73,7 +73,7 @@ class DottyPrimitives(ctx: Context) {
       case JavaArrayType(el) => el
       case _ =>
         ctx.error(s"expected Array $tpe")
-        ErrorType
+        UnspecifiedErrorType
     }
 
     code match {