From f8273c8bc33afde989b46e31eb95f982550b2ad9 Mon Sep 17 00:00:00 2001
From: Dale Wijnand <dale.wijnand@gmail.com>
Date: Thu, 10 Nov 2022 14:21:24 +0000
Subject: [PATCH] Avoid EmptyScope.cloneScope crashing, eg on missing
 references

---
 compiler/src/dotty/tools/dotc/core/Scopes.scala | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/src/dotty/tools/dotc/core/Scopes.scala b/compiler/src/dotty/tools/dotc/core/Scopes.scala
index 863ae4fa6b7f..99076b422358 100644
--- a/compiler/src/dotty/tools/dotc/core/Scopes.scala
+++ b/compiler/src/dotty/tools/dotc/core/Scopes.scala
@@ -467,7 +467,7 @@ object Scopes {
     override def size: Int = 0
     override def nestingLevel: Int = 0
     override def toList(using Context): List[Symbol] = Nil
-    override def cloneScope(using Context): MutableScope = unsupported("cloneScope")
+    override def cloneScope(using Context): MutableScope = newScope(nestingLevel)
     override def lookupEntry(name: Name)(using Context): ScopeEntry | Null = null
     override def lookupNextEntry(entry: ScopeEntry)(using Context): ScopeEntry | Null = null
   }