From 8c18baf10ec89dc0b207f7c1f5c5a0fd5fe2b664 Mon Sep 17 00:00:00 2001
From: arvidn <arvid@libtorrent.org>
Date: Fri, 16 Nov 2018 02:44:11 +0100
Subject: [PATCH] check for self-assignment in bitfield operator=

---
 include/libtorrent/bitfield.hpp | 1 +
 test/test_bitfield.cpp          | 8 ++++++++
 2 files changed, 9 insertions(+)

diff --git a/include/libtorrent/bitfield.hpp b/include/libtorrent/bitfield.hpp
index 1b54d9f2a..2aad3738c 100644
--- a/include/libtorrent/bitfield.hpp
+++ b/include/libtorrent/bitfield.hpp
@@ -145,6 +145,7 @@ namespace libtorrent {
 		// assignment operator
 		bitfield& operator=(bitfield const& rhs)
 		{
+			if (&rhs == this) return *this;
 			assign(rhs.data(), rhs.size());
 			return *this;
 		}
diff --git a/test/test_bitfield.cpp b/test/test_bitfield.cpp
index a1906b8ad..e52eda752 100644
--- a/test/test_bitfield.cpp
+++ b/test/test_bitfield.cpp
@@ -387,6 +387,14 @@ TORRENT_TEST(not_initialized)
 	// get_bit, clear_bit, set_bit
 }
 
+TORRENT_TEST(self_assign)
+{
+	bitfield test1(123, false);
+	test1 = test1;
+	TEST_EQUAL(test1.size(), 123);
+	TEST_EQUAL(test1.count(), 0);
+}
+
 TORRENT_TEST(not_initialized_assign)
 {
 	// check a not initialized empty bitfield