WIP

Author: noti0na1

compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala

@@ -962,6 +962,16 @@ class CheckCaptures extends Recheck, SymTransformer:
         openClosures = openClosures.tail
     end recheckClosureBlock
 
+    override def recheckReturn(tree: Return)(using Context): Type =
+      super.recheckReturn(tree)
+      val sym = tree.symbol
+      if sym.exists then
+        // check that the return type conforms to the expected type
+        val resType = tree.expr.nuType
+        val expectedType = sym.info
+        checkConformsExpr(resType, expectedType, tree)
+      defn.NothingType
+
     /** Elements of a SeqLiteral instantiate a Seq or Array parameter, so they
      *  should be boxed.
      */

compiler/src/dotty/tools/dotc/cc/Setup.scala

@@ -685,6 +685,13 @@ class Setup extends PreRecheck, SymTransformer, SetupAPI:
       case tree: Bind =>
         val sym = tree.symbol
         updateInfo(sym, transformInferredType(sym.info), sym.owner)
+
+      case tree: Labeled =>
+        val sym = tree.bind.symbol
+        if sym.exists then
+          println(i"update info of $sym in ${ctx.owner} from ${sym.info} to ${transformInferredType(sym.info)}, tree = $tree")
+          updateInfo(sym, transformInferredType(sym.info), sym.owner)
+
       case tree: TypeDef =>
         tree.symbol match
           case cls: ClassSymbol =>

tests/neg-custom-args/captures/match.scala

@@ -19,3 +19,8 @@ def test =
 
   val x4: AnyRef = a match
     case b: B => b.x // error
+
+  val x5: AnyRef^{x} = a match
+    case b: B =>
+      val bx: AnyRef^{b.x} = b.x
+      bx