diff --git a/test/libsolidity/util/TestFunctionCall.cpp b/test/libsolidity/util/TestFunctionCall.cpp
index 6adf4fcaf..0e411a458 100644
--- a/test/libsolidity/util/TestFunctionCall.cpp
+++ b/test/libsolidity/util/TestFunctionCall.cpp
@@ -83,12 +83,17 @@ string TestFunctionCall::format(
 		stream << _linePrefix << newline << ws << m_call.signature;
 		if (m_call.value.value > u256(0))
 		{
-			if (m_call.value.unit == FunctionValueUnit::Ether)
+			switch (m_call.value.unit)
+			{
+			case FunctionValueUnit::Ether:
 				stream << comma << ws << (m_call.value.value / exp256(10, 18)) << ws << ether;
-			else if (m_call.value.unit == FunctionValueUnit::Wei)
+				break;
+			case FunctionValueUnit::Wei:
 				stream << comma << ws << m_call.value.value << ws << wei;
-			else
+				break;
+			default:
 				soltestAssert(false, "");
+			}
 		}
 		if (!m_call.arguments.rawBytes().empty())
 		{
@@ -360,6 +365,7 @@ void TestFunctionCall::reset()
 {
 	m_rawBytes = bytes{};
 	m_failure = true;
+	m_contractABI = Json::Value{};
 	m_calledNonExistingFunction = false;
 }
 
diff --git a/test/libsolidity/util/TestFunctionCall.h b/test/libsolidity/util/TestFunctionCall.h
index 839c86553..35ae139ad 100644
--- a/test/libsolidity/util/TestFunctionCall.h
+++ b/test/libsolidity/util/TestFunctionCall.h
@@ -150,7 +150,7 @@ private:
 	bool m_failure = true;
 	/// JSON object which holds the contract ABI and that is used to set the output formatting
 	/// in the interactive update routine.
-	Json::Value m_contractABI;
+	Json::Value m_contractABI = Json::Value{};
 	/// Flags that the test failed because the called function is not known to exist on the contract.
 	bool m_calledNonExistingFunction = false;
 };
diff --git a/test/tools/isoltest.cpp b/test/tools/isoltest.cpp
index 91efedadb..b05cbe84a 100644
--- a/test/tools/isoltest.cpp
+++ b/test/tools/isoltest.cpp
@@ -151,7 +151,6 @@ bool TestTool::m_exitRequested = false;
 TestTool::Result TestTool::process()
 {
 	bool formatted{!m_options.noColor};
-	std::stringstream outputMessages;
 
 	try
 	{
@@ -168,6 +167,8 @@ TestTool::Result TestTool::process()
 				m_options.enforceGasTestMinValue
 			});
 			if (m_test->shouldRun())
+			{
+				std::stringstream outputMessages;
 				switch (TestCase::TestResult result = m_test->run(outputMessages, "  ", formatted))
 				{
 					case TestCase::TestResult::Success:
@@ -183,6 +184,7 @@ TestTool::Result TestTool::process()
 						cout << endl << outputMessages.str() << endl;
 						return result == TestCase::TestResult::FatalError ? Result::Exception : Result::Failure;
 				}
+			}
 			else
 			{
 				AnsiColorized(cout, formatted, {BOLD, YELLOW}) << "NOT RUN" << endl;