From c2287a25baa3470fdc0a42198062dbabf97aedb2 Mon Sep 17 00:00:00 2001
From: Jan Chyb <jan.chyb.99@gmail.com>
Date: Fri, 6 Sep 2024 18:04:35 +0200
Subject: [PATCH] Check if symbol was moved to a companion when bringing
 forward denotation

While bringing forward the denotation to a new run, check if the
symbol was moved from its owner to a companion object. If so, return
NoDenotation, as that denotation seems to be a leftover from
pre-MoveStatics phases in a previous run.
---
 compiler/src/dotty/tools/dotc/core/Denotations.scala |  7 ++++++-
 .../src/dotty/tools/dotc/core/SymDenotations.scala   |  4 ++++
 tests/pos-macros/i21271/Macro.scala                  | 12 ++++++++++++
 tests/pos-macros/i21271/Test.scala                   |  1 +
 4 files changed, 23 insertions(+), 1 deletion(-)
 create mode 100644 tests/pos-macros/i21271/Macro.scala
 create mode 100644 tests/pos-macros/i21271/Test.scala

diff --git a/compiler/src/dotty/tools/dotc/core/Denotations.scala b/compiler/src/dotty/tools/dotc/core/Denotations.scala
index 2418aba1978b..60a7555456bf 100644
--- a/compiler/src/dotty/tools/dotc/core/Denotations.scala
+++ b/compiler/src/dotty/tools/dotc/core/Denotations.scala
@@ -2,7 +2,7 @@ package dotty.tools
 package dotc
 package core
 
-import SymDenotations.{ SymDenotation, ClassDenotation, NoDenotation, LazyType, stillValid, acceptStale, traceInvalid }
+import SymDenotations.{ SymDenotation, ClassDenotation, NoDenotation, LazyType, stillValid, movedToCompanionClass, acceptStale, traceInvalid }
 import Contexts.*
 import Names.*
 import NameKinds.*
@@ -755,6 +755,11 @@ object Denotations {
       }
       if (!symbol.exists) return updateValidity()
       if (!coveredInterval.containsPhaseId(ctx.phaseId)) return NoDenotation
+      // Moved to a companion class, likely at a later phase (in MoveStatics)
+      this match {
+        case symd: SymDenotation if movedToCompanionClass(symd) => return NoDenotation
+        case _ =>
+      }
       if (ctx.debug) traceInvalid(this)
       staleSymbolError
     }
diff --git a/compiler/src/dotty/tools/dotc/core/SymDenotations.scala b/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
index 3904228756a0..906e74735097 100644
--- a/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
+++ b/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
@@ -2680,6 +2680,10 @@ object SymDenotations {
         stillValidInOwner(denot)
     }
 
+  def movedToCompanionClass(denot: SymDenotation)(using Context): Boolean =
+    val ownerCompanion = denot.maybeOwner.companionClass
+    stillValid(ownerCompanion) && ownerCompanion.unforcedDecls.contains(denot.name, denot.symbol)
+
   private[SymDenotations] def stillValidInOwner(denot: SymDenotation)(using Context): Boolean = try
     val owner = denot.maybeOwner.denot
     stillValid(owner)
diff --git a/tests/pos-macros/i21271/Macro.scala b/tests/pos-macros/i21271/Macro.scala
new file mode 100644
index 000000000000..09d29ecc65af
--- /dev/null
+++ b/tests/pos-macros/i21271/Macro.scala
@@ -0,0 +1,12 @@
+import scala.quoted.*
+
+trait Schema
+object Schema:
+  lazy val sampleDate: String = "" // lazy val requried to reproduce
+
+  inline def derived: Schema =
+    annotations
+    new Schema {}
+
+inline def annotations: Int = ${ annotationsImpl }
+def annotationsImpl(using Quotes): Expr[Int] = Expr(1)
diff --git a/tests/pos-macros/i21271/Test.scala b/tests/pos-macros/i21271/Test.scala
new file mode 100644
index 000000000000..c0ba38212b09
--- /dev/null
+++ b/tests/pos-macros/i21271/Test.scala
@@ -0,0 +1 @@
+val inputValueSchema = Schema.derived