From 60b9c9dc1f4a45afe2813abc4234766019862549 Mon Sep 17 00:00:00 2001
From: Yuriy Glukhov <yuriy.glukhov@gmail.com>
Date: Thu, 7 Jun 2018 19:14:14 +0300
Subject: [PATCH] Fixes #7985

---
 compiler/closureiters.nim | 21 ++++++++++-----------
 tests/async/t7985.nim     | 19 +++++++++++++++++++
 2 files changed, 29 insertions(+), 11 deletions(-)
 create mode 100644 tests/async/t7985.nim

diff --git a/compiler/closureiters.nim b/compiler/closureiters.nim
index e8f4d62c1..5568fd37b 100644
--- a/compiler/closureiters.nim
+++ b/compiler/closureiters.nim
@@ -397,18 +397,17 @@ proc hasYieldsInExpressions(n: PNode): bool =
 
 proc exprToStmtList(n: PNode): tuple[s, res: PNode] =
   assert(n.kind == nkStmtListExpr)
-
-  var parent = n
-  var lastSon = n[^1]
-
-  while lastSon.kind == nkStmtListExpr:
-    parent = lastSon
-    lastSon = lastSon[^1]
-
   result.s = newNodeI(nkStmtList, n.info)
-  result.s.sons = parent.sons
-  result.s.sons.setLen(result.s.sons.len - 1) # delete last son
-  result.res = lastSon
+  result.s.sons = @[]
+
+  var n = n
+  while n.kind == nkStmtListExpr:
+    result.s.sons.add(n.sons)
+    result.s.sons.setLen(result.s.sons.len - 1) # delete last son
+    n = n[^1]
+
+  result.res = n
+
 
 proc newEnvVarAsgn(ctx: Ctx, s: PSym, v: PNode): PNode =
   result = newTree(nkFastAsgn, ctx.newEnvVarAccess(s), v)
diff --git a/tests/async/t7985.nim b/tests/async/t7985.nim
new file mode 100644
index 000000000..0365499d3
--- /dev/null
+++ b/tests/async/t7985.nim
@@ -0,0 +1,19 @@
+discard """
+  file: "t7985.nim"
+  exitcode: 0
+  output: "(value: 1)"
+"""
+import json, asyncdispatch
+
+proc getData(): Future[JsonNode] {.async.} =
+  result = %*{"value": 1}
+
+type
+  MyData = object
+    value: BiggestInt
+
+proc main() {.async.} =
+  let data = to(await(getData()), MyData)
+  echo data
+
+waitFor(main())