diff --git a/compiler/injectdestructors.nim b/compiler/injectdestructors.nim
index bec8b49f4f..b18bcf34e1 100644
--- a/compiler/injectdestructors.nim
+++ b/compiler/injectdestructors.nim
@@ -411,7 +411,9 @@ proc passCopyToSink(n: PNode; c: var Con; s: var Scope): PNode =
         "if possible, rearrange your program's control flow to prevent it") % $n)
   else:
     if c.graph.config.selectedGC in {gcArc, gcOrc}:
-      assert(not containsGarbageCollectedRef(n.typ))
+      assert(not containsManagedMemory(n.typ))
+    if n.typ.skipTypes(abstractInst).kind in {tyOpenArray, tyVarargs}:
+      localError(c.graph.config, n.info, "cannot create an implicit openArray copy to be passed to a sink parameter")
     result.add newTree(nkAsgn, tmp, p(n, c, s, normal))
   # Since we know somebody will take over the produced copy, there is
   # no need to destroy it.
diff --git a/compiler/types.nim b/compiler/types.nim
index b9fc4d4a28..b20bf9c06c 100644
--- a/compiler/types.nim
+++ b/compiler/types.nim
@@ -321,6 +321,13 @@ proc containsGarbageCollectedRef*(typ: PType): bool =
   # things that are garbage-collected)
   result = searchTypeFor(typ, isGCRef)
 
+proc isManagedMemory(t: PType): bool =
+  result = t.kind in GcTypeKinds or
+    (t.kind == tyProc and t.callConv == ccClosure)
+
+proc containsManagedMemory*(typ: PType): bool =
+  result = searchTypeFor(typ, isManagedMemory)
+
 proc isTyRef(t: PType): bool =
   result = t.kind == tyRef or (t.kind == tyProc and t.callConv == ccClosure)