1 files changed, 56 insertions, 0 deletions
diff --git a/tests/gc/cycleleak.nim b/tests/gc/cycleleak.nim
new file mode 100644
index 000000000..e355abc96
--- /dev/null
+++ b/tests/gc/cycleleak.nim
@@ -0,0 +1,56 @@
+discard """
+  outputsub: "no leak: "
+"""
+
+type
+  Module = object
+    nodes*: seq[PNode]
+    id: int
+
+  PModule = ref Module
+
+  Node = object
+    owner* {.cursor.}: PModule
+    data*: array[0..200, char] # some fat to drain memory faster
+    id: int
+
+  PNode = ref Node
+
+var
+  gid: int
+
+when false:
+  proc finalizeNode(x: PNode) =
+    echo "node id: ", x.id
+  proc finalizeModule(x: PModule) =
+    echo "module id: ", x.id
+
+proc newNode(owner: PModule): PNode =
+  new(result)
+  result.owner = owner
+  inc gid
+  result.id = gid
+
+proc compileModule: PModule =
+  new(result)
+  result.nodes = @[]
+  for i in 0..100:
+    result.nodes.add newNode(result)
+  inc gid
+  result.id = gid
+
+var gModuleCache: PModule
+
+proc loop =
+  for i in 0..1000:
+    gModuleCache = compileModule()
+    gModuleCache = nil
+    GC_fullCollect()
+
+    if getOccupiedMem() > 9_000_000:
+      echo "still a leak! ", getOccupiedMem()
+      quit(1)
+  echo "no leak: ", getOccupiedMem()
+
+loop()
+