diff --git a/compiler/src/dotty/tools/dotc/ast/Desugar.scala b/compiler/src/dotty/tools/dotc/ast/Desugar.scala
index 42108e10fb85..396cde32599a 100644
--- a/compiler/src/dotty/tools/dotc/ast/Desugar.scala
+++ b/compiler/src/dotty/tools/dotc/ast/Desugar.scala
@@ -578,7 +578,7 @@ object desugar {
       val clsName = moduleName.moduleClassName
       val clsRef = Ident(clsName)
       val modul = ValDef(moduleName, clsRef, New(clsRef, Nil))
-        .withMods(mods | ModuleCreationFlags | mods.flags & AccessFlags)
+        .withMods(mods.toTermFlags & RetainedModuleValFlags | ModuleValCreationFlags)
         .withPos(mdef.pos.startPos)
       val ValDef(selfName, selfTpt, _) = impl.self
       val selfMods = impl.self.mods
diff --git a/compiler/src/dotty/tools/dotc/core/Flags.scala b/compiler/src/dotty/tools/dotc/core/Flags.scala
index e8f71f8a1c28..4bf05f2fbd0b 100644
--- a/compiler/src/dotty/tools/dotc/core/Flags.scala
+++ b/compiler/src/dotty/tools/dotc/core/Flags.scala
@@ -472,7 +472,7 @@ object Flags {
   final val RetainedTypeArgFlags = VarianceFlags | Protected | Local
 
   /** Modules always have these flags set */
-  final val ModuleCreationFlags = ModuleVal | Lazy | Final | Stable
+  final val ModuleValCreationFlags = ModuleVal | Lazy | Final | Stable
 
   /** Module classes always have these flags set */
   final val ModuleClassCreationFlags = ModuleClass | Final
@@ -503,7 +503,7 @@ object Flags {
   /** Flags that can apply to a module val */
   final val RetainedModuleValFlags: FlagSet = RetainedModuleValAndClassFlags |
     Override | Final | Method | Implicit | Lazy |
-    Accessor | AbsOverride | Stable | Captured | Synchronized
+    Accessor | AbsOverride | Stable | Captured | Synchronized | Inline
 
   /** Flags that can apply to a module class */
   final val RetainedModuleClassFlags: FlagSet = RetainedModuleValAndClassFlags | ImplClass | Enum
diff --git a/compiler/src/dotty/tools/dotc/core/Symbols.scala b/compiler/src/dotty/tools/dotc/core/Symbols.scala
index 2e3661a52039..8cddd2e9d70c 100644
--- a/compiler/src/dotty/tools/dotc/core/Symbols.scala
+++ b/compiler/src/dotty/tools/dotc/core/Symbols.scala
@@ -153,7 +153,7 @@ trait Symbols { this: Context =>
         modcls, owner, modclsName, modclsFlags,
         infoFn(module, modcls), privateWithin)
     val mdenot = SymDenotation(
-        module, owner, name, modFlags | ModuleCreationFlags,
+        module, owner, name, modFlags | ModuleValCreationFlags,
         if (cdenot.isCompleted) TypeRef.withSym(owner.thisType, modcls, modclsName)
         else new ModuleCompleter(modcls))
     module.denot = mdenot
diff --git a/compiler/src/dotty/tools/dotc/core/tasty/TreeUnpickler.scala b/compiler/src/dotty/tools/dotc/core/tasty/TreeUnpickler.scala
index 301883ab4e2a..78a0fe11f16b 100644
--- a/compiler/src/dotty/tools/dotc/core/tasty/TreeUnpickler.scala
+++ b/compiler/src/dotty/tools/dotc/core/tasty/TreeUnpickler.scala
@@ -382,7 +382,7 @@ class TreeUnpickler(reader: TastyReader, nameAtRef: NameRef => TermName, posUnpi
       if (lacksDefinition && tag != PARAM) flags |= Deferred
       if (tag == DEFDEF) flags |= Method
       if (givenFlags is Module)
-        flags = flags | (if (tag == VALDEF) ModuleCreationFlags else ModuleClassCreationFlags)
+        flags = flags | (if (tag == VALDEF) ModuleValCreationFlags else ModuleClassCreationFlags)
       if (ctx.owner.isClass) {
         if (tag == TYPEPARAM) flags |= Param
         else if (tag == PARAM) flags |= ParamAccessor
diff --git a/compiler/src/dotty/tools/dotc/typer/Namer.scala b/compiler/src/dotty/tools/dotc/typer/Namer.scala
index 36216adf06dd..a4e989ad9d7e 100644
--- a/compiler/src/dotty/tools/dotc/typer/Namer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Namer.scala
@@ -274,7 +274,7 @@ class Namer { typer: Typer =>
       def preExisting = ctx.effectiveScope.lookup(name)
       if (ctx.owner is PackageClass)
         if (preExisting.isDefinedInCurrentRun)
-          errorName(s"${preExisting.showLocated} has already been compiled\nonce during this run")
+          errorName(s"${preExisting.showLocated} has already been compiled once during this run")
         else name
       else
         if ((!ctx.owner.isClass || name.isTypeName) && preExisting.exists)
diff --git a/tests/pos/i3471.scala b/tests/pos/i3471.scala
new file mode 100644
index 000000000000..9bc9e82537db
--- /dev/null
+++ b/tests/pos/i3471.scala
@@ -0,0 +1 @@
+sealed object Fun