Merge pull request #3648 from dotty-staging/fix-#2730

Fix #2730: Add regression test

Author: allanrenucci

tests/neg/i2730.scala

@@ -0,0 +1,8 @@
+object Test {
+  def test: Unit = {
+    val x = iDontExist(32) // error: not found: iDontExist
+    val y = x
+    x + x
+    println(x)
+  }
+}