1 files changed, 11 insertions, 8 deletions
diff --git a/src/dotty/tools/dotc/typer/Typer.scala b/src/dotty/tools/dotc/typer/Typer.scala
index 3d36905f2..10d7516e6 100644
--- a/src/dotty/tools/dotc/typer/Typer.scala
+++ b/src/dotty/tools/dotc/typer/Typer.scala
@@ -1022,17 +1022,20 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit
     val DefDef(name, tparams, vparamss, tpt, _) = ddef
     completeAnnotations(ddef, sym)
     val tparams1 = tparams mapconserve (typed(_).asInstanceOf[TypeDef])
-    // for secondary constructors we need to use that their type parameters
-    // are aliases of the class type parameters. See pos/i941.scala
-    if (sym.isConstructor && !sym.isPrimaryConstructor)
-      (sym.owner.typeParams, tparams1).zipped.foreach {(tparam, tdef) =>
-        tdef.symbol.info = TypeAlias(tparam.typeRef)
-       }
-
     val vparamss1 = vparamss nestedMapconserve (typed(_).asInstanceOf[ValDef])
     if (sym is Implicit) checkImplicitParamsNotSingletons(vparamss1)
     val tpt1 = checkSimpleKinded(typedType(tpt))
-    val rhs1 = typedExpr(ddef.rhs, tpt1.tpe)
+
+    var rhsCtx = ctx
+    if (sym.isConstructor && !sym.isPrimaryConstructor && tparams1.nonEmpty) {
+      // for secondary constructors we need a context that "knows"
+      // that their type parameters are aliases of the class type parameters.
+      // See pos/i941.scala
+      rhsCtx = ctx.fresh.setFreshGADTBounds
+      (tparams1, sym.owner.typeParams).zipped.foreach ((tdef, tparam) =>
+        rhsCtx.gadt.setBounds(tdef.symbol, TypeAlias(tparam.typeRef)))
+    }
+    val rhs1 = typedExpr(ddef.rhs, tpt1.tpe)(rhsCtx)
     assignType(cpy.DefDef(ddef)(name, tparams1, vparamss1, tpt1, rhs1), sym)
     //todo: make sure dependent method types do not depend on implicits or by-name params
   }