diff --git a/.gitignore b/.gitignore
index 6f15a4cb4..750826475 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,8 +1,8 @@
-#Third-Party libs
-resources/3rdparty/log4cplus-1.1.0/
-resources/3rdparty/gtest-1.6.0/
-resources/3rdparty/eigen/
-resources/3rdparty/gmm-4.2/
+##Third-Party libs
+resources/3rdparty/log4cplus-1.1.0/**
+resources/3rdparty/gtest-1.6.0/**
+resources/3rdparty/eigen/**
+resources/3rdparty/gmm-4.2/**
 #Visual Studio files
 *.[Oo]bj
 *.user
@@ -25,6 +25,8 @@ resources/3rdparty/gmm-4.2/
 *.sdf
 *.opensdf
 *.unsuccessfulbuild
+# XCode directories and files
+storm/**
 ipch/
 obj/
 CMakeFiles/
diff --git a/test/parser/ParseMdpTest.cpp b/test/parser/ParseMdpTest.cpp
index 4147c0122..cfa50f1c7 100644
--- a/test/parser/ParseMdpTest.cpp
+++ b/test/parser/ParseMdpTest.cpp
@@ -12,7 +12,7 @@
 #include "src/utility/IoUtility.h"
 
 TEST(ParseMdpTest, parseAndOutput) {
-	storm::parser::MdpParser* mdpParser;
+	storm::parser::MdpParser* mdpParser = nullptr;
 	ASSERT_NO_THROW(mdpParser = new storm::parser::MdpParser(
 			STORM_CPP_TESTS_BASE_PATH "/parser/tra_files/mdp_general_input_01.tra",
 			STORM_CPP_TESTS_BASE_PATH "/parser/lab_files/pctl_general_input_01.lab"));
diff --git a/test/parser/ReadLabFileTest.cpp b/test/parser/ReadLabFileTest.cpp
index e7e2df029..9b1d72241 100644
--- a/test/parser/ReadLabFileTest.cpp
+++ b/test/parser/ReadLabFileTest.cpp
@@ -23,7 +23,7 @@ TEST(ReadLabFileTest, ParseTest) {
 	//This test is based on a test case from the original MRMC.
 	
 	
-	storm::parser::AtomicPropositionLabelingParser* parser;
+	storm::parser::AtomicPropositionLabelingParser* parser = nullptr;
 	//Parsing the file
 	ASSERT_NO_THROW(parser = new storm::parser::AtomicPropositionLabelingParser(12, STORM_CPP_TESTS_BASE_PATH "/parser/lab_files/pctl_general_input_01.lab"));
 	std::shared_ptr<storm::models::AtomicPropositionsLabeling> labeling(parser->getLabeling());
@@ -32,7 +32,7 @@ TEST(ReadLabFileTest, ParseTest) {
 
 	char phi[] = "phi", psi[] = "psi", smth[] = "smth";
 
-	if (labeling != NULL) {
+	if (labeling != nullptr) {
 		ASSERT_TRUE(labeling->containsAtomicProposition(phi));
 		ASSERT_TRUE(labeling->containsAtomicProposition(psi));
 		ASSERT_TRUE(labeling->containsAtomicProposition(smth));
diff --git a/test/parser/ReadTraFileTest.cpp b/test/parser/ReadTraFileTest.cpp
index 17cfec798..6a697536d 100644
--- a/test/parser/ReadTraFileTest.cpp
+++ b/test/parser/ReadTraFileTest.cpp
@@ -26,7 +26,7 @@ TEST(ReadTraFileTest, ParseFileTest1) {
 	ASSERT_NO_THROW(parser = new storm::parser::DeterministicSparseTransitionParser(STORM_CPP_TESTS_BASE_PATH "/parser/tra_files/csl_general_input_01.tra"));
 	std::shared_ptr<storm::storage::SparseMatrix<double>> result = parser->getMatrix();
 
-	if (result != NULL) {
+	if (result != nullptr) {
 		double val = 0;
 		ASSERT_TRUE(result->getValue(0, 0, &val));
 		ASSERT_EQ(val, 0.0);