From 3532c7174f9a167740154018b1d95e8c86af6079 Mon Sep 17 00:00:00 2001
From: Mike J Innes <mike.j.innes@gmail.com>
Date: Mon, 22 May 2017 17:32:10 +0100
Subject: [PATCH] early throw on cyclic graphs

---
 src/compiler/interp.jl | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/compiler/interp.jl b/src/compiler/interp.jl
index f3fe4a21..2e307006 100644
--- a/src/compiler/interp.jl
+++ b/src/compiler/interp.jl
@@ -15,6 +15,7 @@ end
 
 function interp(ctx, f, xs...)
   g = graph(f)
+  g ≠ nothing && iscyclic(g) && error("Can't interpret cyclic graph")
   @icatch(ctx, g ≠ nothing ?
     interpret(ctx, reifyparams(g), xs...) :
     f(xs...))