diff --git a/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala b/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala
index 3e3ce7745896..455f643f4934 100644
--- a/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala
+++ b/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala
@@ -1117,7 +1117,7 @@ abstract class ClassfileParser(reader: ReusableInstance[ReusableDataReader]) {
           isScalaRaw = true
           i = numAttrs
         case tpnme.TASTYATTR if !YtastyReader =>
-          reporter.warning(NoPosition, s"Add -Ytasty-reader to scalac options to parse the TASTy in $file")
+          MissingRequirementError.signal(s"Add -Ytasty-reader to scalac options to parse the TASTy in $file")
         case tpnme.TASTYATTR =>
           isTASTY = true
           TASTYAttrLen = attrLen