From eea2a63607bcad56edda614e49635c4f32c941ae Mon Sep 17 00:00:00 2001
From: Andreas Rumpf <rumpf_a@web.de>
Date: Sat, 30 Jan 2016 15:45:45 +0100
Subject: [PATCH] fixes #3794

---
 compiler/ccgtrav.nim                           |  2 ++
 tests/ccgbugs/tmissing_ccgtrav_unique_type.nim | 12 ++++++++++++
 2 files changed, 14 insertions(+)
 create mode 100644 tests/ccgbugs/tmissing_ccgtrav_unique_type.nim

diff --git a/compiler/ccgtrav.nim b/compiler/ccgtrav.nim
index 5f59702e55..0da6396ead 100644
--- a/compiler/ccgtrav.nim
+++ b/compiler/ccgtrav.nim
@@ -57,6 +57,8 @@ proc parentObj(accessor: Rope; m: BModule): Rope {.inline.} =
 
 proc genTraverseProc(c: var TTraversalClosure, accessor: Rope, typ: PType) =
   if typ == nil: return
+
+  let typ = getUniqueType(typ)
   var p = c.p
   case typ.kind
   of tyGenericInst, tyGenericBody, tyTypeDesc:
diff --git a/tests/ccgbugs/tmissing_ccgtrav_unique_type.nim b/tests/ccgbugs/tmissing_ccgtrav_unique_type.nim
new file mode 100644
index 0000000000..cb87eabd8c
--- /dev/null
+++ b/tests/ccgbugs/tmissing_ccgtrav_unique_type.nim
@@ -0,0 +1,12 @@
+
+# bug #3794
+
+
+import options
+
+proc getRef*(): Option[int] =
+  return none(int)
+
+proc getChild*() =
+  let iter = iterator (): int {.closure.} =
+    let reference = getRef()