From 35fa7b30574244e4f99373f2a790f004b4a1dbbb Mon Sep 17 00:00:00 2001
From: Bogdan Vukobratovic <bogdan.vukobratovic@gmail.com>
Date: Thu, 27 Jun 2019 22:02:12 +0200
Subject: [PATCH] Fix memory leak when one of multiple DFF cells is removed in
 opt_rmdff

When there are multiple DFFs and one of them is removed, its reference lingers
inside bit2driver dict. While invoking handle_dff() function for other DFFs,
this broken reference is used isnside sat_import_cell() function.
---
 passes/opt/opt_rmdff.cc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/passes/opt/opt_rmdff.cc b/passes/opt/opt_rmdff.cc
index 5fc28ae92..17e0d7cd4 100644
--- a/passes/opt/opt_rmdff.cc
+++ b/passes/opt/opt_rmdff.cc
@@ -530,6 +530,11 @@ delete_dff:
 	log("Removing %s (%s) from module %s.\n", log_id(dff), log_id(dff->type), log_id(mod));
 	remove_init_attr(dff->getPort("\\Q"));
 	mod->remove(dff);
+
+	for (auto &entry : bit2driver)
+		if (entry.second == dff)
+			bit2driver.erase(entry.first);
+
 	return true;
 }