From a32ad13a86a24013c1570f020de71bbb4df89180 Mon Sep 17 00:00:00 2001
From: laanwj <126646+laanwj@users.noreply.github.com>
Date: Tue, 14 Nov 2023 11:06:25 +0100
Subject: [PATCH] ecp5: Don't segfault while packing FFs when DI port of
 TRELLIS_FF unconnected

Currently a segfault happens when the DI port is not specified. Leaving
it unconnected is probably incorrect, but it shouldn't crash the placer.
Fix by adding a check.
---
 ecp5/pack.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ecp5/pack.cc b/ecp5/pack.cc
index df139860..69d7ccf8 100644
--- a/ecp5/pack.cc
+++ b/ecp5/pack.cc
@@ -240,7 +240,7 @@ class Ecp5Packer
                     ci->disconnectPort(id_M);
                     ci->ports.erase(id_M);
                 }
-                if (di->driver.cell != nullptr && di->driver.cell->type == id_TRELLIS_COMB && di->driver.port == id_F) {
+                if (di && di->driver.cell != nullptr && di->driver.cell->type == id_TRELLIS_COMB && di->driver.port == id_F) {
                     CellInfo *comb = di->driver.cell;
                     if (comb->cluster != ClusterId()) {
                         // Special procedure where the comb cell is part of an existing macro