From fbc48c2275b5b3f594af25e2be05a392d3e10449 Mon Sep 17 00:00:00 2001
From: Martin Odersky <odersky@gmail.com>
Date: Sun, 31 Dec 2017 15:27:39 +0100
Subject: [PATCH] Handle SkolemTypes in avoid

---
 compiler/src/dotty/tools/dotc/typer/TypeAssigner.scala |  2 ++
 tests/pos/i3637.scala                                  | 10 ++++++++++
 2 files changed, 12 insertions(+)
 create mode 100644 tests/pos/i3637.scala

diff --git a/compiler/src/dotty/tools/dotc/typer/TypeAssigner.scala b/compiler/src/dotty/tools/dotc/typer/TypeAssigner.scala
index bd7662032daf..59210fde2ea7 100644
--- a/compiler/src/dotty/tools/dotc/typer/TypeAssigner.scala
+++ b/compiler/src/dotty/tools/dotc/typer/TypeAssigner.scala
@@ -110,6 +110,8 @@ trait TypeAssigner {
           }
         case tp: ThisType if toAvoid(tp.cls) =>
           range(tp.bottomType, apply(classBound(tp.cls.classInfo)))
+        case tp: SkolemType if partsToAvoid(mutable.Set.empty, tp.info).nonEmpty =>
+          range(tp.info.bottomType, apply(tp.info))
         case tp: TypeVar if ctx.typerState.constraint.contains(tp) =>
           val lo = ctx.typeComparer.instanceType(tp.origin, fromBelow = variance >= 0)
           val lo1 = apply(lo)
diff --git a/tests/pos/i3637.scala b/tests/pos/i3637.scala
new file mode 100644
index 000000000000..542199800701
--- /dev/null
+++ b/tests/pos/i3637.scala
@@ -0,0 +1,10 @@
+import reflect.ClassTag
+
+object Demo {
+  def the[T](implicit ev: T): ev.type = ev // More precise implicitly, needed to crash
+
+  {
+    case class B(i: Int)
+    the[ClassTag[B]] // Has to be the last statement of the block
+  }
+}