2 files changed, 20 insertions, 0 deletions
diff --git a/test/files/neg/t3854.check b/test/files/neg/t3854.check
new file mode 100644
index 0000000000..c478481a6f
--- /dev/null
+++ b/test/files/neg/t3854.check
@@ -0,0 +1,5 @@
+t3854.scala:1: error: class Bar needs to be abstract, since method foo in trait Foo of type [G[_]](implicit n: N[G,F])X[F] is not defined
+(Note that N[G,F] does not match M[G])
+class Bar[F[_]] extends Foo[F] {
+      ^
+one error found
diff --git a/test/files/neg/t3854.scala b/test/files/neg/t3854.scala
new file mode 100644
index 0000000000..e8db76c0a5
--- /dev/null
+++ b/test/files/neg/t3854.scala
@@ -0,0 +1,15 @@
+class Bar[F[_]] extends Foo[F] {
+  def foo[G[_[_], _]](implicit M: M[G]): X[({type λ[α] = G[F, α] })#λ] = null
+}
+// vim: set ts=4 sw=4 et:
+
+trait M[F[_[_], _]]
+trait N[F[_], G[_]]
+
+trait X[F[_]] {
+  def apply[A]: F[A]
+}
+
+trait Foo[F[_]] {
+  def foo[G[_]](implicit n: N[G, F]): X[F]
+}