From b3e006fc72bd7c489b62716bc89d4f6f390d79a2 Mon Sep 17 00:00:00 2001
From: odersky <odersky@gmail.com>
Date: Fri, 25 Mar 2022 11:39:25 +0100
Subject: [PATCH] Don't force LazyRefs when computing DepStatus

Fixes #14771
---
 compiler/src/dotty/tools/dotc/core/Types.scala |  3 +++
 tests/pos/i14771.scala                         | 13 +++++++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 tests/pos/i14771.scala

diff --git a/compiler/src/dotty/tools/dotc/core/Types.scala b/compiler/src/dotty/tools/dotc/core/Types.scala
index 24acce54cc4b..14ffa150818b 100644
--- a/compiler/src/dotty/tools/dotc/core/Types.scala
+++ b/compiler/src/dotty/tools/dotc/core/Types.scala
@@ -3635,6 +3635,9 @@ object Types {
             if ann.refersToParamOf(thisLambdaType) then TrueDeps
             else compute(status, parent, theAcc)
           case _: ThisType | _: BoundType | NoPrefix => status
+          case t: LazyRef =>
+            if t.completed then compute(status, t.ref, theAcc)
+            else Unknown
           case _ =>
             (if theAcc != null then theAcc else DepAcc()).foldOver(status, tp)
       compute(initial, tp, null)
diff --git a/tests/pos/i14771.scala b/tests/pos/i14771.scala
new file mode 100644
index 000000000000..31b12602fd00
--- /dev/null
+++ b/tests/pos/i14771.scala
@@ -0,0 +1,13 @@
+trait Layouts:
+  type Layout <: {
+    def withName(name: String): Layout
+  }
+  val l: Layout
+
+val ls = new Layouts:
+  class Layout17:
+    def withName(name: String): Layout17 = this
+  type Layout = Layout17
+  val l = Layout17()
+
+def test = ls.l