From 71a7f3fabd17f5f6966fc56aa3a89bcd6e8be6af Mon Sep 17 00:00:00 2001
From: Akash Levy <akashlevy@gmail.com>
Date: Wed, 14 Aug 2024 16:00:03 -0700
Subject: [PATCH] Fix for segfaulting

---
 passes/cmds/splitfanout.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/passes/cmds/splitfanout.cc b/passes/cmds/splitfanout.cc
index 3fba251a0..1adaabec2 100644
--- a/passes/cmds/splitfanout.cc
+++ b/passes/cmds/splitfanout.cc
@@ -118,7 +118,9 @@ struct SplitfanoutWorker
 			}
 			else {
 				Wire *new_wire = module->addWire(NEW_ID, GetSize(outsig));
-				SigSpec sig = module->cell(std::get<0>(bit_user))->getPort(std::get<1>(bit_user));
+				Cell *target_cell = module->cell(std::get<0>(bit_user));
+				if (!target_cell) continue; // cell might no longer exist
+				SigSpec sig = target_cell->getPort(std::get<1>(bit_user));
 				sig.replace(std::get<2>(bit_user), new_wire);
 				module->cell(std::get<0>(bit_user))->setPort(std::get<1>(bit_user), sig);
 				new_cell->setPort(outport, new_wire);