Merge pull request #3491 from retronym/backport/7902v2.10.4-RC3v2.10.4

[backport] SI-7902 Fix spurious kind error due to an unitialized symbol

2 files changed, 19 insertions, 1 deletions

diff --git a/src/reflect/scala/reflect/internal/Kinds.scala b/src/reflect/scala/reflect/internal/Kinds.scala
index 08686832ef..3ab7b20ecd 100644
--- a/src/reflect/scala/reflect/internal/Kinds.scala
+++ b/src/reflect/scala/reflect/internal/Kinds.scala
@@ -184,6 +184,7 @@ trait Kinds {
           )
         }
         else {
+          hkarg.initialize // SI-7902 otherwise hkarg.typeParams yields List(NoSymbol)!
           debuglog("checkKindBoundsHK recursing to compare params of "+ hkparam +" with "+ hkarg)
           kindErrors ++= checkKindBoundsHK(
             hkarg.typeParams,
@@ -229,4 +230,4 @@ trait Kinds {
       }
     }
   }
-}
\ No newline at end of file
+}
diff --git a/test/files/pos/t7902.scala b/test/files/pos/t7902.scala
new file mode 100644
index 0000000000..47c525c179
--- /dev/null
+++ b/test/files/pos/t7902.scala
@@ -0,0 +1,17 @@
+import scala.language.higherKinds
+
+object Bug {
+  class Tag[W[M1[X1]]]
+
+  def ofType[W[M2[X2]]]: Tag[W] = ???
+  type InSeq  [M3[X3]] = Some[M3[Any]]
+
+  // fail
+  val x = ofType[InSeq]
+
+  // okay
+  val y: Any = ofType[InSeq]
+  object T {
+    val z = ofType[InSeq]
+  }
+}