From 52a4ce6b4c01c3dd6274bea6886283e406b2f21b Mon Sep 17 00:00:00 2001
From: James Cherry <cherry@parallaxsw.com>
Date: Wed, 11 Nov 2020 10:01:15 -0700
Subject: [PATCH] Network::libertyPort

---
 network/Network.cc | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/network/Network.cc b/network/Network.cc
index e282e114..86f173b2 100644
--- a/network/Network.cc
+++ b/network/Network.cc
@@ -120,7 +120,11 @@ Network::libertyCell(const Instance *instance) const
 LibertyPort *
 Network::libertyPort(const Pin *pin) const
 {
-  return libertyPort(port(pin));
+  Port *port = this->port(pin);
+  if (port)
+    return libertyPort(port);
+  else
+    return nullptr;
 }
 
 bool