diff --git a/common/src/main/scala/scalan/util/CollectionUtil.scala b/common/src/main/scala/scalan/util/CollectionUtil.scala
index 7a5d6cf646..bba14c516f 100644
--- a/common/src/main/scala/scalan/util/CollectionUtil.scala
+++ b/common/src/main/scala/scalan/util/CollectionUtil.scala
@@ -168,6 +168,7 @@ object CollectionUtil {
   implicit class HashMapOps[K,V](val source: java.util.HashMap[K,V]) extends AnyVal {
     def toImmutableMap: Map[K,V] = {
       var res = Map[K,V]()
+      // don't beautify: at least this code should compile under java 1.7
       val entries = source.entrySet().iterator()
       while (entries.hasNext) {
         val e = entries.next()
diff --git a/sigmastate/src/test/scala/sigmastate/helpers/SigmaTestingCommons.scala b/sigmastate/src/test/scala/sigmastate/helpers/SigmaTestingCommons.scala
index 3a953dc122..0589eeeb1f 100644
--- a/sigmastate/src/test/scala/sigmastate/helpers/SigmaTestingCommons.scala
+++ b/sigmastate/src/test/scala/sigmastate/helpers/SigmaTestingCommons.scala
@@ -196,13 +196,6 @@ trait SigmaTestingCommons extends PropSpec
     val positionLimitBefore = r.positionLimit
     serializer.parse(r) shouldBe v
     r.positionLimit shouldBe positionLimitBefore
-
-    // using ergo's(scorex) reader/writer
-//    val w = new VLQByteStringWriter()
-//    serializer.serializeWithGenericWriter(v, w)
-//    val byteStr = w.result()
-//    byteStr.nonEmpty shouldBe true
-//    serializer.parseWithGenericReader(new VLQByteStringReader(byteStr)) shouldEqual v
   }
 
   protected def roundTripTestWithPos[T](v: T)(implicit serializer: SigmaSerializer[T, T]): Assertion = {