diff --git a/lib/base/scriptutils.cpp b/lib/base/scriptutils.cpp
index 50659bdc3..0f7b97449 100644
--- a/lib/base/scriptutils.cpp
+++ b/lib/base/scriptutils.cpp
@@ -151,6 +151,8 @@ Array::Ptr ScriptUtils::Range(const std::vector<Value>& arguments)
 			end = arguments[1];
 			increment = arguments[2];
 			break;
+		default:
+			BOOST_THROW_EXCEPTION(std::invalid_argument("Invalid number of arguments for range()"));
 	}
 
 	Array::Ptr result = make_shared<Array>();
diff --git a/lib/base/threadpool.cpp b/lib/base/threadpool.cpp
index ea8b4304c..ba2e5dc9e 100644
--- a/lib/base/threadpool.cpp
+++ b/lib/base/threadpool.cpp
@@ -33,10 +33,10 @@ using namespace icinga;
 
 int ThreadPool::m_NextID = 1;
 
-ThreadPool::ThreadPool(int max_threads)
+ThreadPool::ThreadPool(size_t max_threads)
 	: m_ID(m_NextID++), m_MaxThreads(max_threads), m_Stopped(false)
 {
-	if (m_MaxThreads != -1 && m_MaxThreads < sizeof(m_Queues) / sizeof(m_Queues[0]))
+	if (m_MaxThreads != UINT_MAX && m_MaxThreads < sizeof(m_Queues) / sizeof(m_Queues[0]))
 		m_MaxThreads = sizeof(m_Queues) / sizeof(m_Queues[0]);
 
 	Start();
@@ -242,7 +242,7 @@ void ThreadPool::ManagerThreadProc(void)
 				break;
 		}
 
-		for (int i = 0; i < sizeof(m_Queues) / sizeof(m_Queues[0]); i++) {
+		for (size_t i = 0; i < sizeof(m_Queues) / sizeof(m_Queues[0]); i++) {
 			size_t pending, alive = 0;
 			double avg_latency;
 			double utilization = 0;
@@ -287,7 +287,7 @@ void ThreadPool::ManagerThreadProc(void)
 				if (tthreads > 0 && pending > 0)
 					tthreads = 8;
 
-				if (m_MaxThreads != -1 && (alive + tthreads) * (sizeof(m_Queues) / sizeof(m_Queues[0])) > m_MaxThreads)
+				if (m_MaxThreads != UINT_MAX && (alive + tthreads) * (sizeof(m_Queues) / sizeof(m_Queues[0])) > m_MaxThreads)
 					tthreads = m_MaxThreads / (sizeof(m_Queues) / sizeof(m_Queues[0])) - alive;
 
 				if (tthreads != 0) {
@@ -383,7 +383,7 @@ void ThreadPool::WorkerThread::UpdateUtilization(ThreadState state)
 			utilization = 1;
 			break;
 		default:
-			ASSERT(0);
+			VERIFY(0);
 	}
 
 	double now = Utility::GetTime();
diff --git a/lib/base/threadpool.h b/lib/base/threadpool.h
index 7460a5d21..3949e70b2 100644
--- a/lib/base/threadpool.h
+++ b/lib/base/threadpool.h
@@ -40,7 +40,7 @@ class I2_BASE_API ThreadPool
 public:
 	typedef boost::function<void ()> WorkFunction;
 
-	ThreadPool(int max_threads = -1);
+	ThreadPool(size_t max_threads = UINT_MAX);
 	~ThreadPool(void);
 
 	void Start(void);
@@ -110,7 +110,7 @@ private:
 	int m_ID;
 	static int m_NextID;
 
-	unsigned int m_MaxThreads;
+	size_t m_MaxThreads;
 
 	boost::thread_group m_ThreadGroup;
 
diff --git a/lib/icinga/legacytimeperiod.cpp b/lib/icinga/legacytimeperiod.cpp
index 84a4cbfe5..e9256da47 100644
--- a/lib/icinga/legacytimeperiod.cpp
+++ b/lib/icinga/legacytimeperiod.cpp
@@ -402,7 +402,6 @@ Dictionary::Ptr LegacyTimePeriod::FindNextSegment(const String& daydef, const St
 		iter = begin;
 
 		tsend = mktime(&end);
-		tsiter = mktime(&iter);
 
 		do {
 			if (IsInTimeRange(&begin, &end, stride, &iter)) {