diff --git a/Jamfile b/Jamfile
index 41090d318..edc1f7dba 100644
--- a/Jamfile
+++ b/Jamfile
@@ -421,7 +421,7 @@ feature.compose <ipv6>off : <define>TORRENT_USE_IPV6=0 ;
 
 feature sanitize : off address undefined thread rtc : composite propagated link-incompatible ;
 # sanitize is a clang and GCC feature
-feature.compose <sanitize>undefined : <cflags>-fsanitize=undefined <linkflags>-fsanitize=undefined ;
+feature.compose <sanitize>undefined : <cflags>-fsanitize=undefined <cflags>-fsanitize-undefined-trap-on-error <linkflags>-fsanitize=undefined ;
 feature.compose <sanitize>thread : <cflags>-fsanitize=thread <linkflags>-fsanitize=thread ;
 feature.compose <sanitize>address : <cflags>-fsanitize=address <linkflags>-fsanitize=address ;
 # RTC (runtime check) is an msvc feature
diff --git a/include/libtorrent/alert_manager.hpp b/include/libtorrent/alert_manager.hpp
index beac278fd..f308b8c2c 100644
--- a/include/libtorrent/alert_manager.hpp
+++ b/include/libtorrent/alert_manager.hpp
@@ -93,8 +93,8 @@ namespace libtorrent {
 			// don't add more than this number of alerts, unless it's a
 			// high priority alert, in which case we try harder to deliver it
 			// for high priority alerts, double the upper limit
-			if (m_alerts[m_generation].size() >= m_queue_size_limit
-				* (1 + T::priority))
+			if (m_alerts[m_generation].size() / (1 + T::priority)
+				>= m_queue_size_limit)
 				return;
 
 			T alert(m_allocations[m_generation], std::forward<Args>(args)...);
@@ -118,8 +118,8 @@ namespace libtorrent {
 		bool should_post() const
 		{
 			recursive_mutex::scoped_lock lock(m_mutex);
-			if (m_alerts[m_generation].size() >= m_queue_size_limit
-				* (1 + T::priority))
+			if (m_alerts[m_generation].size() / (1 + T::priority)
+				>= m_queue_size_limit)
 			{
 				return false;
 			}
diff --git a/include/libtorrent/aux_/alert_manager_variadic_emplace.hpp b/include/libtorrent/aux_/alert_manager_variadic_emplace.hpp
index 180632edd..3cca6181e 100644
--- a/include/libtorrent/aux_/alert_manager_variadic_emplace.hpp
+++ b/include/libtorrent/aux_/alert_manager_variadic_emplace.hpp
@@ -37,8 +37,8 @@
 			// don't add more than this number of alerts, unless it's a
 			// high priority alert, in which case we try harder to deliver it
 			// for high priority alerts, double the upper limit
-			if (m_alerts[m_generation].size() >= m_queue_size_limit
-				* (1 + T::priority))
+			if (m_alerts[m_generation].size() / (1 + T::priority)
+				>= m_queue_size_limit)
 				return;
 
 			T alert(m_allocations[m_generation]
diff --git a/test/test_alert_manager.cpp b/test/test_alert_manager.cpp
index a1de83797..fbb2c5ecc 100644
--- a/test/test_alert_manager.cpp
+++ b/test/test_alert_manager.cpp
@@ -81,6 +81,26 @@ TORRENT_TEST(limit)
 	TEST_EQUAL(alerts.size(), 200);
 }
 
+TORRENT_TEST(limit_int_max)
+{
+	int const inf = std::numeric_limits<int>::max();
+	alert_manager mgr(inf, 0xffffffff);
+
+	TEST_EQUAL(mgr.alert_queue_size_limit(), inf);
+
+	for (int i = 0; i < 600; ++i)
+		mgr.emplace_alert<piece_finished_alert>(torrent_handle(), i);
+
+	for (int i = 0; i < 600; ++i)
+		mgr.emplace_alert<torrent_removed_alert>(torrent_handle(), sha1_hash());
+
+	std::vector<alert*> alerts;
+	int num_resume;
+	mgr.get_all(alerts, num_resume);
+
+	TEST_EQUAL(alerts.size(), 1200);
+}
+
 TORRENT_TEST(priority_limit)
 {
 	alert_manager mgr(100, 0xffffffff);