diff --git a/compiler/semtypinst.nim b/compiler/semtypinst.nim
index bd2b25c24e..4ab0e2de10 100644
--- a/compiler/semtypinst.nim
+++ b/compiler/semtypinst.nim
@@ -45,7 +45,8 @@ proc searchInstTypes*(g: ModuleGraph; key: PType): PType =
       # XXX: This happens for prematurely cached
       # types such as Channel[empty]. Why?
       # See the notes for PActor in handleGenericInvocation
-      return
+      # if this is return the same type gets cached more than it needs to
+      continue
     if not sameFlags(inst, key):
       continue
 
diff --git a/tests/generics/t17509.nim b/tests/generics/t17509.nim
new file mode 100644
index 0000000000..89f507577d
--- /dev/null
+++ b/tests/generics/t17509.nim
@@ -0,0 +1,25 @@
+type List[O] = object
+  next: ptr List[O]
+
+proc initList[O](l: ptr List[O]) =
+  l[].next = l
+
+type
+  PolytopeVertex[R] = object
+    list: List[PolytopeVertex[R]]
+
+  PolytopeEdge[R] = object
+    list: List[PolytopeEdge[R]]
+
+  Polytope[R] = object
+    vertices: List[PolytopeVertex[R]]
+    edges: List[PolytopeEdge[R]]
+
+var pt: Polytope[float]
+
+static:
+  doAssert pt.vertices.next is (ptr List[PolytopeVertex[float]])
+  doAssert pt.edges.next is (ptr List[PolytopeEdge[float]])
+
+initList(addr pt.vertices)
+initList(addr pt.edges)
\ No newline at end of file