From 8c8825b9ce1ec04a812142d85ec1369c4c0d2ca7 Mon Sep 17 00:00:00 2001
From: Andreas Rumpf <rumpf_a@web.de>
Date: Mon, 28 Mar 2016 09:50:27 +0200
Subject: [PATCH] fixes #3975

---
 compiler/semstmts.nim | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/compiler/semstmts.nim b/compiler/semstmts.nim
index 5d16f2fba..910267e57 100644
--- a/compiler/semstmts.nim
+++ b/compiler/semstmts.nim
@@ -620,7 +620,8 @@ proc semFor(c: PContext, n: PNode): PNode =
       result.kind = nkParForStmt
     else:
       result = semForFields(c, n, call.sons[0].sym.magic)
-  elif isCallExpr and call.sons[0].typ.callConv == ccClosure:
+  elif isCallExpr and call.sons[0].typ.callConv == ccClosure and
+      tfIterator in call.sons[0].typ.flags:
     # first class iterator:
     result = semForVars(c, n)
   elif not isCallExpr or call.sons[0].kind != nkSym or