diff --git a/src/class_diagram/generators/plantuml/class_diagram_generator.cc b/src/class_diagram/generators/plantuml/class_diagram_generator.cc
index 997f2d20..dd85f2db 100644
--- a/src/class_diagram/generators/plantuml/class_diagram_generator.cc
+++ b/src/class_diagram/generators/plantuml/class_diagram_generator.cc
@@ -438,19 +438,19 @@ void generator::generate(const package &p, std::ostream &ostr) const
     }
 
     for (const auto &subpackage : p) {
-        if (dynamic_cast<package *>(subpackage.get())) {
+        if (dynamic_cast<package *>(subpackage.get()) != nullptr) {
             // TODO: add option - generate_empty_packages
             const auto &sp = dynamic_cast<package &>(*subpackage);
             if (!sp.is_empty())
                 generate(sp, ostr);
         }
-        else if (dynamic_cast<class_ *>(subpackage.get())) {
+        else if (dynamic_cast<class_ *>(subpackage.get()) != nullptr) {
             if (m_model.should_include(*subpackage)) {
                 generate_alias(dynamic_cast<class_ &>(*subpackage), ostr);
                 generate(dynamic_cast<class_ &>(*subpackage), ostr);
             }
         }
-        else if (dynamic_cast<enum_ *>(subpackage.get())) {
+        else if (dynamic_cast<enum_ *>(subpackage.get()) != nullptr) {
             if (m_model.should_include(*subpackage)) {
                 generate_alias(dynamic_cast<enum_ &>(*subpackage), ostr);
                 generate(dynamic_cast<enum_ &>(*subpackage), ostr);
@@ -473,19 +473,19 @@ void generator::generate_relationships(
     const package &p, std::ostream &ostr) const
 {
     for (const auto &subpackage : p) {
-        if (dynamic_cast<package *>(subpackage.get())) {
+        if (dynamic_cast<package *>(subpackage.get()) != nullptr) {
             // TODO: add option - generate_empty_packages
             const auto &sp = dynamic_cast<package &>(*subpackage);
             if (!sp.is_empty())
                 generate_relationships(sp, ostr);
         }
-        else if (dynamic_cast<class_ *>(subpackage.get())) {
+        else if (dynamic_cast<class_ *>(subpackage.get()) != nullptr) {
             if (m_model.should_include(*subpackage)) {
                 generate_relationships(
                     dynamic_cast<class_ &>(*subpackage), ostr);
             }
         }
-        else if (dynamic_cast<enum_ *>(subpackage.get())) {
+        else if (dynamic_cast<enum_ *>(subpackage.get()) != nullptr) {
             if (m_model.should_include(*subpackage)) {
                 generate_relationships(
                     dynamic_cast<enum_ &>(*subpackage), ostr);
@@ -503,18 +503,18 @@ void generator::generate(std::ostream &ostr) const
     generate_plantuml_directives(ostr, m_config.puml().before);
 
     for (const auto &p : m_model) {
-        if (dynamic_cast<package *>(p.get())) {
+        if (dynamic_cast<package *>(p.get()) != nullptr) {
             const auto &sp = dynamic_cast<package &>(*p);
             if (!sp.is_empty())
                 generate(sp, ostr);
         }
-        else if (dynamic_cast<class_ *>(p.get())) {
+        else if (dynamic_cast<class_ *>(p.get()) != nullptr) {
             if (m_model.should_include(*p)) {
                 generate_alias(dynamic_cast<class_ &>(*p), ostr);
                 generate(dynamic_cast<class_ &>(*p), ostr);
             }
         }
-        else if (dynamic_cast<enum_ *>(p.get())) {
+        else if (dynamic_cast<enum_ *>(p.get()) != nullptr) {
             if (m_model.should_include(*p)) {
                 generate_alias(dynamic_cast<enum_ &>(*p), ostr);
                 generate(dynamic_cast<enum_ &>(*p), ostr);
@@ -523,15 +523,15 @@ void generator::generate(std::ostream &ostr) const
     }
 
     for (const auto &p : m_model) {
-        if (dynamic_cast<package *>(p.get())) {
+        if (dynamic_cast<package *>(p.get()) != nullptr) {
             generate_relationships(dynamic_cast<package &>(*p), ostr);
         }
-        else if (dynamic_cast<class_ *>(p.get())) {
+        else if (dynamic_cast<class_ *>(p.get()) != nullptr) {
             if (m_model.should_include(*p)) {
                 generate_relationships(dynamic_cast<class_ &>(*p), ostr);
             }
         }
-        else if (dynamic_cast<enum_ *>(p.get())) {
+        else if (dynamic_cast<enum_ *>(p.get()) != nullptr) {
             if (m_model.should_include(*p)) {
                 generate_relationships(dynamic_cast<enum_ &>(*p), ostr);
             }
diff --git a/src/class_diagram/visitor/translation_unit_visitor.cc b/src/class_diagram/visitor/translation_unit_visitor.cc
index 040775f8..011a3ec6 100644
--- a/src/class_diagram/visitor/translation_unit_visitor.cc
+++ b/src/class_diagram/visitor/translation_unit_visitor.cc
@@ -127,7 +127,7 @@ bool translation_unit_visitor::VisitEnumDecl(clang::EnumDecl *enm)
 
     const auto *parent = enm->getParent();
 
-    if (parent && parent->isRecord()) {
+    if ((parent != nullptr) && parent->isRecord()) {
         // Here we have 2 options, either:
         //  - the parent is a regular C++ class/struct
         //  - the parent is a class template declaration/specialization
@@ -140,7 +140,7 @@ bool translation_unit_visitor::VisitEnumDecl(clang::EnumDecl *enm)
         // If not, check if the parent template declaration is in the model
         if (!id_opt) {
             if (static_cast<const clang::RecordDecl *>(parent)
-                    ->getDescribedTemplate()) {
+                    ->getDescribedTemplate() != nullptr) {
                 local_id = static_cast<const clang::RecordDecl *>(parent)
                                ->getDescribedTemplate()
                                ->getID();
@@ -209,7 +209,7 @@ bool translation_unit_visitor::VisitClassTemplateSpecializationDecl(
         cls->getLocation().printToString(source_manager()));
 
     // TODO: Add support for classes defined in function/method bodies
-    if (cls->isLocalClass())
+    if (cls->isLocalClass() != nullptr)
         return true;
 
     auto template_specialization_ptr = process_template_specialization(cls);
@@ -353,7 +353,7 @@ bool translation_unit_visitor::VisitCXXRecordDecl(clang::CXXRecordDecl *cls)
                 ->getQualifiedNameAsString());
     }
 
-    if (cls->isTemplated() && cls->getDescribedTemplate()) {
+    if (cls->isTemplated() && (cls->getDescribedTemplate() != nullptr)) {
         // If the described templated of this class is already in the model
         // skip it:
         if (get_ast_local_id(cls->getDescribedTemplate()->getID()))
@@ -361,7 +361,7 @@ bool translation_unit_visitor::VisitCXXRecordDecl(clang::CXXRecordDecl *cls)
     }
 
     // TODO: Add support for classes defined in function/method bodies
-    if (cls->isLocalClass())
+    if (cls->isLocalClass() != nullptr)
         return true;
 
     auto c_ptr = create_class_declaration(cls);
@@ -420,7 +420,7 @@ std::unique_ptr<class_> translation_unit_visitor::create_class_declaration(
 
     const auto *parent = cls->getParent();
 
-    if (parent && parent->isRecord()) {
+    if ((parent != nullptr) && parent->isRecord()) {
         // Here we have 2 options, either:
         //  - the parent is a regular C++ class/struct
         //  - the parent is a class template declaration/specialization
@@ -438,7 +438,7 @@ std::unique_ptr<class_> translation_unit_visitor::create_class_declaration(
                            ->getDescribedTemplate()
                            ->getID();
             if (static_cast<const clang::RecordDecl *>(parent)
-                    ->getDescribedTemplate())
+                    ->getDescribedTemplate() != nullptr)
                 id_opt = get_ast_local_id(local_id);
         }
 
@@ -523,7 +523,8 @@ bool translation_unit_visitor::process_template_parameters(
 
     for (const auto *parameter :
         *template_declaration.getTemplateParameters()) {
-        if (clang::dyn_cast_or_null<clang::TemplateTypeParmDecl>(parameter)) {
+        if (clang::dyn_cast_or_null<clang::TemplateTypeParmDecl>(parameter) !=
+            nullptr) {
             const auto *template_type_parameter =
                 clang::dyn_cast_or_null<clang::TemplateTypeParmDecl>(parameter);
             template_parameter ct;
@@ -536,7 +537,7 @@ bool translation_unit_visitor::process_template_parameters(
             c.add_template(std::move(ct));
         }
         else if (clang::dyn_cast_or_null<clang::NonTypeTemplateParmDecl>(
-                     parameter)) {
+                     parameter) != nullptr) {
             const auto *template_nontype_parameter =
                 clang::dyn_cast_or_null<clang::NonTypeTemplateParmDecl>(
                     parameter);
@@ -550,7 +551,7 @@ bool translation_unit_visitor::process_template_parameters(
             c.add_template(std::move(ct));
         }
         else if (clang::dyn_cast_or_null<clang::TemplateTemplateParmDecl>(
-                     parameter)) {
+                     parameter) != nullptr) {
             const auto *template_template_parameter =
                 clang::dyn_cast_or_null<clang::TemplateTemplateParmDecl>(
                     parameter);
@@ -579,9 +580,9 @@ void translation_unit_visitor::process_template_record_containment(
 
     const auto *parent = record.getParent(); //->getOuterLexicalRecordContext();
 
-    if (parent &&
-        static_cast<const clang::RecordDecl *>(parent)
-            ->getDescribedTemplate()) {
+    if ((parent != nullptr) &&
+        (static_cast<const clang::RecordDecl *>(parent)
+                ->getDescribedTemplate() != nullptr)) {
         auto id_opt =
             get_ast_local_id(static_cast<const clang::RecordDecl *>(parent)
                                  ->getDescribedTemplate()
@@ -687,7 +688,7 @@ void translation_unit_visitor::process_template_specialization_children(
         if (decl->getKind() == clang::Decl::Var) {
             const clang::VarDecl *variable_declaration{
                 dynamic_cast<const clang::VarDecl *>(decl)};
-            if (variable_declaration &&
+            if ((variable_declaration != nullptr) &&
                 variable_declaration->isStaticDataMember()) {
                 process_static_field(*variable_declaration, c);
             }
@@ -749,7 +750,7 @@ void translation_unit_visitor::process_class_children(
         if (decl->getKind() == clang::Decl::Var) {
             const clang::VarDecl *variable_declaration{
                 dynamic_cast<const clang::VarDecl *>(decl)};
-            if (variable_declaration &&
+            if ((variable_declaration != nullptr) &&
                 variable_declaration->isStaticDataMember()) {
                 process_static_field(*variable_declaration, c);
             }
@@ -787,7 +788,7 @@ void translation_unit_visitor::process_friend(
             nullptr) {
             // TODO: handle template friend
         }
-        else if (friend_type->getAs<clang::RecordType>()) {
+        else if (friend_type->getAs<clang::RecordType>() != nullptr) {
             const auto friend_type_name =
                 friend_type->getAsRecordDecl()->getQualifiedNameAsString();
             if (diagram().should_include(friend_type_name)) {
@@ -938,7 +939,7 @@ bool translation_unit_visitor::find_relationships(const clang::QualType &type,
                     // pass
                 }
                 else if (template_argument.getAsType()
-                             ->getAs<clang::FunctionProtoType>()) {
+                             ->getAs<clang::FunctionProtoType>() != nullptr) {
                     for (const auto &param_type :
                         template_argument.getAsType()
                             ->getAs<clang::FunctionProtoType>()
@@ -1184,7 +1185,8 @@ void translation_unit_visitor::process_template_specialization_argument(
 
         // If this is a nested template type - add nested templates as
         // template arguments
-        if (arg.getAsType()->getAs<clang::TemplateSpecializationType>()) {
+        if (arg.getAsType()->getAs<clang::TemplateSpecializationType>() !=
+            nullptr) {
             const auto *nested_template_type =
                 arg.getAsType()->getAs<clang::TemplateSpecializationType>();
 
@@ -1210,7 +1212,8 @@ void translation_unit_visitor::process_template_specialization_argument(
             simplify_system_template(argument,
                 argument.to_string(config().using_namespace(), false));
         }
-        else if (arg.getAsType()->getAs<clang::TemplateTypeParmType>()) {
+        else if (arg.getAsType()->getAs<clang::TemplateTypeParmType>() !=
+            nullptr) {
             auto type_name =
                 common::to_string(arg.getAsType(), cls->getASTContext());
 
@@ -1480,8 +1483,8 @@ std::unique_ptr<class_> translation_unit_visitor::build_template_instantiation(
 
     auto *template_type_ptr = &template_type_decl;
     if (template_type_decl.isTypeAlias() &&
-        template_type_decl.getAliasedType()
-            ->getAs<clang::TemplateSpecializationType>())
+        (template_type_decl.getAliasedType()
+                ->getAs<clang::TemplateSpecializationType>() != nullptr))
         template_type_ptr = template_type_decl.getAliasedType()
                                 ->getAs<clang::TemplateSpecializationType>();
 
@@ -1505,8 +1508,9 @@ std::unique_ptr<class_> translation_unit_visitor::build_template_instantiation(
     auto *class_template_decl{
         clang::dyn_cast<clang::ClassTemplateDecl>(template_decl)};
 
-    if (class_template_decl && class_template_decl->getTemplatedDecl() &&
-        class_template_decl->getTemplatedDecl()->getParent() &&
+    if ((class_template_decl != nullptr) &&
+        (class_template_decl->getTemplatedDecl() != nullptr) &&
+        (class_template_decl->getTemplatedDecl()->getParent() != nullptr) &&
         class_template_decl->getTemplatedDecl()->getParent()->isRecord()) {
 
         namespace_ ns{
@@ -1559,7 +1563,8 @@ std::unique_ptr<class_> translation_unit_visitor::build_template_instantiation(
         clang::dyn_cast_or_null<clang::CXXRecordDecl>(
             template_decl->getTemplatedDecl());
 
-    if (templated_class_decl && templated_class_decl->hasDefinition())
+    if ((templated_class_decl != nullptr) &&
+        templated_class_decl->hasDefinition())
         for (const auto &base : templated_class_decl->bases()) {
             const auto base_class_name = common::to_string(
                 base.getType(), templated_class_decl->getASTContext(), false);
@@ -1738,19 +1743,19 @@ void translation_unit_visitor::
 
     // If this is a nested template type - add nested templates as
     // template arguments
-    if (arg.getAsType()->getAs<clang::FunctionType>()) {
+    if (arg.getAsType()->getAs<clang::FunctionType>() != nullptr) {
 
         for (const auto &param_type :
             arg.getAsType()->getAs<clang::FunctionProtoType>()->param_types()) {
 
-            if (!param_type->getAs<clang::RecordType>())
+            if (param_type->getAs<clang::RecordType>() == nullptr)
                 continue;
 
             auto *classTemplateSpecialization =
                 llvm::dyn_cast<clang::ClassTemplateSpecializationDecl>(
                     param_type->getAsRecordDecl());
 
-            if (classTemplateSpecialization) {
+            if (classTemplateSpecialization != nullptr) {
                 // Read arg info as needed.
                 auto nested_template_instantiation =
                     build_template_instantiation_from_class_template_specialization(
@@ -1784,7 +1789,8 @@ void translation_unit_visitor::
             }
         }
     }
-    else if (arg.getAsType()->getAs<clang::TemplateSpecializationType>()) {
+    else if (arg.getAsType()->getAs<clang::TemplateSpecializationType>() !=
+        nullptr) {
         const auto *nested_template_type =
             arg.getAsType()->getAs<clang::TemplateSpecializationType>();
 
@@ -1836,7 +1842,7 @@ void translation_unit_visitor::
             diagram().add_class(std::move(nested_template_instantiation));
         }
     }
-    else if (arg.getAsType()->getAs<clang::TemplateTypeParmType>()) {
+    else if (arg.getAsType()->getAs<clang::TemplateTypeParmType>() != nullptr) {
         argument.is_template_parameter(true);
         argument.set_name(
             common::to_string(arg.getAsType(), template_decl->getASTContext()));
@@ -1884,8 +1890,9 @@ void translation_unit_visitor::
     argument.set_name(
         common::to_string(arg.getAsType(), template_decl->getASTContext()));
 
-    if (arg.getAsType()->getAs<clang::RecordType>() &&
-        arg.getAsType()->getAs<clang::RecordType>()->getAsRecordDecl()) {
+    if ((arg.getAsType()->getAs<clang::RecordType>() != nullptr) &&
+        (arg.getAsType()->getAs<clang::RecordType>()->getAsRecordDecl() !=
+            nullptr)) {
         argument.set_id(common::to_id(arg));
 
         if (diagram().should_include(full_template_specialization_name)) {
@@ -1895,8 +1902,9 @@ void translation_unit_visitor::
                 {relationship_t::kDependency, common::to_id(arg)});
         }
     }
-    else if (arg.getAsType()->getAs<clang::EnumType>()) {
-        if (arg.getAsType()->getAs<clang::EnumType>()->getAsTagDecl()) {
+    else if (arg.getAsType()->getAs<clang::EnumType>() != nullptr) {
+        if (arg.getAsType()->getAs<clang::EnumType>()->getAsTagDecl() !=
+            nullptr) {
             template_instantiation.add_relationship(
                 {relationship_t::kDependency, common::to_id(arg)});
         }
@@ -2087,7 +2095,7 @@ void translation_unit_visitor::process_field(
         // Find relationship for the type if the type has not been added
         // as aggregation
         if (!template_instantiation_added_as_aggregation) {
-            if (field_type->getAsCXXRecordDecl() &&
+            if ((field_type->getAsCXXRecordDecl() != nullptr) &&
                 field_type->getAsCXXRecordDecl()->getNameAsString().empty()) {
                 // Relationships to fields whose type is an anonymous nested
                 // struct have to be handled separately here
diff --git a/src/common/clang_utils.cc b/src/common/clang_utils.cc
index 0e2c1e81..ab9538b0 100644
--- a/src/common/clang_utils.cc
+++ b/src/common/clang_utils.cc
@@ -67,13 +67,13 @@ model::namespace_ get_tag_namespace(const clang::TagDecl &declaration)
     const auto *parent{declaration.getParent()};
 
     // First walk up to the nearest namespace, e.g. from nested class or enum
-    while (parent && !parent->isNamespace()) {
+    while ((parent != nullptr) && !parent->isNamespace()) {
         parent = parent->getParent();
     }
 
     // Now build up the namespace
     std::deque<std::string> namespace_tokens;
-    while (parent && parent->isNamespace()) {
+    while ((parent != nullptr) && parent->isNamespace()) {
         const auto *ns_decl = static_cast<const clang::NamespaceDecl *>(parent);
         if (!ns_decl->isInline() && !ns_decl->isAnonymousNamespace())
             namespace_tokens.push_front(ns_decl->getNameAsString());
@@ -96,7 +96,8 @@ std::string get_tag_name(const clang::TagDecl &declaration)
             fmt::format("(anonymous_{})", std::to_string(declaration.getID()));
     }
 
-    if (declaration.getParent() && declaration.getParent()->isRecord()) {
+    if ((declaration.getParent() != nullptr) &&
+        declaration.getParent()->isRecord()) {
         // If the record is nested within another record (e.g. class or struct)
         // we have to maintain a containment namespace in order to ensure
         // unique names within the diagram
@@ -190,7 +191,8 @@ std::string to_string(const clang::FunctionTemplateDecl *decl)
     std::vector<std::string> template_parameters;
     // Handle template function
     for (const auto *parameter : *decl->getTemplateParameters()) {
-        if (clang::dyn_cast_or_null<clang::TemplateTypeParmDecl>(parameter)) {
+        if (clang::dyn_cast_or_null<clang::TemplateTypeParmDecl>(parameter) !=
+            nullptr) {
             const auto *template_type_parameter =
                 clang::dyn_cast_or_null<clang::TemplateTypeParmDecl>(parameter);
 
@@ -282,11 +284,12 @@ template <> id_t to_id(const std::filesystem::path &file)
 template <> id_t to_id(const clang::TemplateArgument &template_argument)
 {
     if (template_argument.getKind() == clang::TemplateArgument::Type) {
-        if (template_argument.getAsType()->getAs<clang::EnumType>())
+        if (template_argument.getAsType()->getAs<clang::EnumType>() != nullptr)
             return to_id(*template_argument.getAsType()
                               ->getAs<clang::EnumType>()
                               ->getAsTagDecl());
-        if (template_argument.getAsType()->getAs<clang::RecordType>())
+        if (template_argument.getAsType()->getAs<clang::RecordType>() !=
+            nullptr)
             return to_id(*template_argument.getAsType()
                               ->getAs<clang::RecordType>()
                               ->getAsRecordDecl());
diff --git a/src/config/config.cc b/src/config/config.cc
index 0ecb0ccc..3bfb8b88 100644
--- a/src/config/config.cc
+++ b/src/config/config.cc
@@ -135,31 +135,31 @@ std::vector<std::string> diagram::get_translation_units(
 
 void diagram::initialize_type_aliases()
 {
-    if (!type_aliases().count("std::basic_string<char>")) {
+    if (type_aliases().count("std::basic_string<char>") == 0u) {
         type_aliases().insert({"std::basic_string<char>", "std::string"});
     }
-    if (!type_aliases().count("std::basic_string<char,std::char_traits<"
-                              "char>,std::allocator<char>>")) {
+    if (type_aliases().count("std::basic_string<char,std::char_traits<"
+                             "char>,std::allocator<char>>") == 0u) {
         type_aliases().insert({"std::basic_string<char,std::char_traits<"
                                "char>,std::allocator<char>>",
             "std::string"});
     }
-    if (!type_aliases().count("std::basic_string<wchar_t>")) {
+    if (type_aliases().count("std::basic_string<wchar_t>") == 0u) {
         type_aliases().insert({"std::basic_string<wchar_t>", "std::wstring"});
     }
-    if (!type_aliases().count("std::basic_string<char16_t>")) {
+    if (type_aliases().count("std::basic_string<char16_t>") == 0u) {
         type_aliases().insert(
             {"std::basic_string<char16_t>", "std::u16string"});
     }
-    if (!type_aliases().count("std::basic_string<char32_t>")) {
+    if (type_aliases().count("std::basic_string<char32_t>") == 0u) {
         type_aliases().insert(
             {"std::basic_string<char32_t>", "std::u32string"});
     }
-    if (!type_aliases().count("std::integral_constant<bool,true>")) {
+    if (type_aliases().count("std::integral_constant<bool,true>") == 0u) {
         type_aliases().insert(
             {"std::integral_constant<bool,true>", "std::true_type"});
     }
-    if (!type_aliases().count("std::integral_constant<bool,false>")) {
+    if (type_aliases().count("std::integral_constant<bool,false>") == 0u) {
         type_aliases().insert(
             {"std::integral_constant<bool,false>", "std::false_type"});
     }
@@ -189,24 +189,24 @@ void class_diagram::initialize_relationship_hints()
 {
     using common::model::relationship_t;
 
-    if (!relationship_hints().count("std::vector")) {
+    if (relationship_hints().count("std::vector") == 0u) {
         relationship_hints().insert({"std::vector", {}});
     }
-    if (!relationship_hints().count("std::unique_ptr")) {
+    if (relationship_hints().count("std::unique_ptr") == 0u) {
         relationship_hints().insert({"std::unique_ptr", {}});
     }
-    if (!relationship_hints().count("std::shared_ptr")) {
+    if (relationship_hints().count("std::shared_ptr") == 0u) {
         relationship_hints().insert(
             {"std::shared_ptr", {relationship_t::kAssociation}});
     }
-    if (!relationship_hints().count("std::weak_ptr")) {
+    if (relationship_hints().count("std::weak_ptr") == 0u) {
         relationship_hints().insert(
             {"std::weak_ptr", {relationship_t::kAssociation}});
     }
-    if (!relationship_hints().count("std::tuple")) {
+    if (relationship_hints().count("std::tuple") == 0u) {
         relationship_hints().insert({"std::tuple", {}});
     }
-    if (!relationship_hints().count("std::map")) {
+    if (relationship_hints().count("std::map") == 0u) {
         relationship_hint_t hint{relationship_t::kNone};
         hint.argument_hints.insert({1, relationship_t::kAggregation});
         relationship_hints().insert({"std::tuple", std::move(hint)});
diff --git a/src/cx/util.cc b/src/cx/util.cc
index cff5d3b4..7e7686a2 100644
--- a/src/cx/util.cc
+++ b/src/cx/util.cc
@@ -49,7 +49,7 @@ parse_unexposed_template_params(const std::string &params,
     std::vector<template_parameter> res;
 
     auto it = params.begin();
-    while (std::isspace(*it))
+    while (std::isspace(*it) != 0)
         ++it;
 
     std::string type{};
diff --git a/src/decorators/decorators.cc b/src/decorators/decorators.cc
index bfd5f35f..0e3f96e9 100644
--- a/src/decorators/decorators.cc
+++ b/src/decorators/decorators.cc
@@ -91,7 +91,7 @@ decorator_toks decorator::tokenize(const std::string &label, std::string_view c)
 
         std::advance(it, res.param.size() + 1);
     }
-    else if (std::isspace(*it)) {
+    else if (std::isspace(*it) != 0) {
         std::advance(it, 1);
     }
 
diff --git a/src/main.cc b/src/main.cc
index 0383dfb3..3dc9e44b 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -331,7 +331,7 @@ void generate_diagrams(const std::vector<std::string> &diagram_names,
                 translation_units = valid_translation_units, verbose]() {
                 try {
                     generate_diagram(
-                        od, name, diagram, db, translation_units, verbose);
+                        od, name, diagram, db, translation_units, verbose != 0);
                 }
                 catch (std::runtime_error &e) {
                     LOG_ERROR(e.what());
diff --git a/src/package_diagram/visitor/translation_unit_visitor.cc b/src/package_diagram/visitor/translation_unit_visitor.cc
index fb58525c..7b85dea8 100644
--- a/src/package_diagram/visitor/translation_unit_visitor.cc
+++ b/src/package_diagram/visitor/translation_unit_visitor.cc
@@ -221,7 +221,7 @@ void translation_unit_visitor::process_class_children(
         if (decl->getKind() == clang::Decl::Var) {
             const clang::VarDecl *variable_declaration{
                 dynamic_cast<const clang::VarDecl *>(decl)};
-            if (variable_declaration &&
+            if ((variable_declaration != nullptr) &&
                 variable_declaration->isStaticDataMember()) {
                 process_static_field(*variable_declaration, relationships);
             }
@@ -374,7 +374,7 @@ bool translation_unit_visitor::find_relationships(const clang::QualType &type,
                     // pass
                 }
                 else if (template_argument.getAsType()
-                             ->getAs<clang::FunctionProtoType>()) {
+                             ->getAs<clang::FunctionProtoType>() != nullptr) {
                     for (const auto &param_type :
                         template_argument.getAsType()
                             ->getAs<clang::FunctionProtoType>()
diff --git a/src/sequence_diagram/visitor/call_expression_context.cc b/src/sequence_diagram/visitor/call_expression_context.cc
index b367d065..1fffe7e9 100644
--- a/src/sequence_diagram/visitor/call_expression_context.cc
+++ b/src/sequence_diagram/visitor/call_expression_context.cc
@@ -59,16 +59,16 @@ bool call_expression_context::valid() const
 
 clang::ASTContext *call_expression_context::get_ast_context()
 {
-    if (current_class_template_specialization_decl_)
+    if (current_class_template_specialization_decl_ != nullptr)
         return &current_class_template_specialization_decl_->getASTContext();
 
-    if (current_class_template_decl_)
+    if (current_class_template_decl_ != nullptr)
         return &current_class_template_decl_->getASTContext();
 
-    if (current_class_decl_)
+    if (current_class_decl_ != nullptr)
         return &current_class_decl_->getASTContext();
 
-    if (current_function_template_decl_)
+    if (current_function_template_decl_ != nullptr)
         return &current_function_template_decl_->getASTContext();
 
     return &current_function_decl_->getASTContext();
@@ -104,7 +104,7 @@ void call_expression_context::update(clang::FunctionDecl *function)
 
     // Check if this function is a part of template function declaration,
     // If no - reset the current_function_template_decl_
-    if (current_function_template_decl_ &&
+    if ((current_function_template_decl_ != nullptr) &&
         current_function_template_decl_->getQualifiedNameAsString() !=
             function->getQualifiedNameAsString()) {
         current_function_template_decl_ = nullptr;
@@ -318,13 +318,13 @@ void call_expression_context::leave_conditionaloperator()
 bool call_expression_context::is_expr_in_current_control_statement_condition(
     const clang::Stmt *stmt) const
 {
-    if (current_ifstmt()) {
+    if (current_ifstmt() != nullptr) {
         if (common::is_subexpr_of(current_ifstmt()->getCond(), stmt)) {
             return true;
         }
     }
 
-    if (current_elseifstmt()) {
+    if (current_elseifstmt() != nullptr) {
         if (common::is_subexpr_of(current_elseifstmt()->getCond(), stmt)) {
             return true;
         }
@@ -367,7 +367,7 @@ bool call_expression_context::is_expr_in_current_control_statement_condition(
             }
         }
 
-        if (current_conditionaloperator()) {
+        if (current_conditionaloperator() != nullptr) {
             if (common::is_subexpr_of(
                     current_conditionaloperator()->getCond(), stmt)) {
                 return true;
diff --git a/src/sequence_diagram/visitor/translation_unit_visitor.cc b/src/sequence_diagram/visitor/translation_unit_visitor.cc
index e95869d7..f1989304 100644
--- a/src/sequence_diagram/visitor/translation_unit_visitor.cc
+++ b/src/sequence_diagram/visitor/translation_unit_visitor.cc
@@ -74,7 +74,7 @@ bool translation_unit_visitor::VisitCXXRecordDecl(clang::CXXRecordDecl *cls)
     if (!should_include(cls))
         return true;
 
-    if (cls->isTemplated() && cls->getDescribedTemplate()) {
+    if (cls->isTemplated() && (cls->getDescribedTemplate() != nullptr)) {
         // If the described templated of this class is already in the model
         // skip it:
         auto local_id = cls->getDescribedTemplate()->getID();
@@ -83,7 +83,7 @@ bool translation_unit_visitor::VisitCXXRecordDecl(clang::CXXRecordDecl *cls)
     }
 
     // TODO: Add support for classes defined in function/method bodies
-    if (cls->isLocalClass())
+    if (cls->isLocalClass() != nullptr)
         return true;
 
     LOG_TRACE("Visiting class declaration at {}",
@@ -192,7 +192,7 @@ bool translation_unit_visitor::VisitClassTemplateSpecializationDecl(
         cls->getLocation().printToString(source_manager()));
 
     // TODO: Add support for classes defined in function/method bodies
-    if (cls->isLocalClass())
+    if (cls->isLocalClass() != nullptr)
         return true;
 
     auto template_specialization_ptr = process_template_specialization(cls);
@@ -233,7 +233,7 @@ bool translation_unit_visitor::VisitCXXMethodDecl(clang::CXXMethodDecl *m)
         return true;
 
     if (!m->isThisDeclarationADefinition()) {
-        if (m->getDefinition())
+        if (m->getDefinition() != nullptr)
             return VisitCXXMethodDecl(
                 static_cast<clang::CXXMethodDecl *>(m->getDefinition()));
     }
@@ -256,7 +256,7 @@ bool translation_unit_visitor::VisitCXXMethodDecl(clang::CXXMethodDecl *m)
 
     clang::Decl *parent_decl = m->getParent();
 
-    if (context().current_class_template_decl_)
+    if (context().current_class_template_decl_ != nullptr)
         parent_decl = context().current_class_template_decl_;
 
     LOG_DBG("Getting method's class with local id {}", parent_decl->getID());
@@ -325,7 +325,7 @@ bool translation_unit_visitor::VisitFunctionDecl(clang::FunctionDecl *f)
     const auto function_name = f->getQualifiedNameAsString();
 
     if (!f->isThisDeclarationADefinition()) {
-        if (f->getDefinition())
+        if (f->getDefinition() != nullptr)
             return VisitFunctionDecl(
                 static_cast<clang::FunctionDecl *>(f->getDefinition()));
     }
@@ -334,7 +334,7 @@ bool translation_unit_visitor::VisitFunctionDecl(clang::FunctionDecl *f)
         f->getLocation().printToString(source_manager()));
 
     if (f->isTemplated()) {
-        if (f->getDescribedTemplate()) {
+        if (f->getDescribedTemplate() != nullptr) {
             // If the described templated of this function is already in the
             // model skip it:
             if (get_unique_id(f->getDescribedTemplate()->getID()))
@@ -551,7 +551,7 @@ bool translation_unit_visitor::TraverseCompoundStmt(clang::CompoundStmt *stmt)
         if (current_elseifstmt->getElse() == stmt) {
             const auto current_caller_id = context().caller_id();
 
-            if (current_caller_id) {
+            if (current_caller_id != 0) {
                 diagram()
                     .get_activity(current_caller_id)
                     .add_message({message_t::kElse, current_caller_id});
@@ -562,7 +562,7 @@ bool translation_unit_visitor::TraverseCompoundStmt(clang::CompoundStmt *stmt)
         if (current_ifstmt->getElse() == stmt) {
             const auto current_caller_id = context().caller_id();
 
-            if (current_caller_id) {
+            if (current_caller_id != 0) {
                 diagram()
                     .get_activity(current_caller_id)
                     .add_message({message_t::kElse, current_caller_id});
@@ -598,7 +598,7 @@ bool translation_unit_visitor::TraverseIfStmt(clang::IfStmt *stmt)
         }
     }
 
-    if (current_caller_id && !stmt->isConstexpr()) {
+    if ((current_caller_id != 0) && !stmt->isConstexpr()) {
         context().enter_ifstmt(stmt);
         if (elseif_block) {
             context().enter_elseifstmt(stmt);
@@ -611,7 +611,7 @@ bool translation_unit_visitor::TraverseIfStmt(clang::IfStmt *stmt)
 
     RecursiveASTVisitor<translation_unit_visitor>::TraverseIfStmt(stmt);
 
-    if (current_caller_id && !stmt->isConstexpr() && !elseif_block) {
+    if ((current_caller_id != 0) && !stmt->isConstexpr() && !elseif_block) {
         diagram().end_if_stmt(current_caller_id, message_t::kIfEnd);
     }
 
@@ -626,13 +626,13 @@ bool translation_unit_visitor::TraverseWhileStmt(clang::WhileStmt *stmt)
 
     const auto current_caller_id = context().caller_id();
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().enter_loopstmt(stmt);
         diagram().add_while_stmt(current_caller_id);
     }
     RecursiveASTVisitor<translation_unit_visitor>::TraverseWhileStmt(stmt);
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         diagram().end_while_stmt(current_caller_id);
         context().leave_loopstmt();
     }
@@ -648,14 +648,14 @@ bool translation_unit_visitor::TraverseDoStmt(clang::DoStmt *stmt)
 
     const auto current_caller_id = context().caller_id();
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().enter_loopstmt(stmt);
         diagram().add_do_stmt(current_caller_id);
     }
 
     RecursiveASTVisitor<translation_unit_visitor>::TraverseDoStmt(stmt);
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().leave_loopstmt();
         diagram().end_do_stmt(current_caller_id);
     }
@@ -671,14 +671,14 @@ bool translation_unit_visitor::TraverseForStmt(clang::ForStmt *stmt)
 
     const auto current_caller_id = context().caller_id();
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().enter_loopstmt(stmt);
         diagram().add_for_stmt(current_caller_id);
     }
 
     RecursiveASTVisitor<translation_unit_visitor>::TraverseForStmt(stmt);
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().leave_loopstmt();
         diagram().end_for_stmt(current_caller_id);
     }
@@ -694,14 +694,14 @@ bool translation_unit_visitor::TraverseCXXTryStmt(clang::CXXTryStmt *stmt)
 
     const auto current_caller_id = context().caller_id();
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().enter_trystmt(stmt);
         diagram().add_try_stmt(current_caller_id);
     }
 
     RecursiveASTVisitor<translation_unit_visitor>::TraverseCXXTryStmt(stmt);
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().leave_trystmt();
         diagram().end_try_stmt(current_caller_id);
     }
@@ -717,7 +717,7 @@ bool translation_unit_visitor::TraverseCXXCatchStmt(clang::CXXCatchStmt *stmt)
 
     const auto current_caller_id = context().caller_id();
 
-    if (current_caller_id && context().current_trystmt()) {
+    if ((current_caller_id != 0) && (context().current_trystmt() != nullptr)) {
         std::string caught_type;
         if (stmt->getCaughtType().isNull())
             caught_type = "...";
@@ -742,7 +742,7 @@ bool translation_unit_visitor::TraverseCXXForRangeStmt(
 
     const auto current_caller_id = context().caller_id();
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().enter_loopstmt(stmt);
         diagram().add_for_stmt(current_caller_id);
     }
@@ -750,7 +750,7 @@ bool translation_unit_visitor::TraverseCXXForRangeStmt(
     RecursiveASTVisitor<translation_unit_visitor>::TraverseCXXForRangeStmt(
         stmt);
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().leave_loopstmt();
         diagram().end_for_stmt(current_caller_id);
     }
@@ -762,14 +762,14 @@ bool translation_unit_visitor::TraverseSwitchStmt(clang::SwitchStmt *stmt)
 {
     const auto current_caller_id = context().caller_id();
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().enter_switchstmt(stmt);
         diagram().add_switch_stmt(current_caller_id);
     }
 
     RecursiveASTVisitor<translation_unit_visitor>::TraverseSwitchStmt(stmt);
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().leave_switchstmt();
         diagram().end_switch_stmt(current_caller_id);
     }
@@ -781,7 +781,7 @@ bool translation_unit_visitor::TraverseCaseStmt(clang::CaseStmt *stmt)
 {
     const auto current_caller_id = context().caller_id();
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         diagram().add_case_stmt(
             current_caller_id, common::to_string(stmt->getLHS()));
     }
@@ -795,7 +795,7 @@ bool translation_unit_visitor::TraverseDefaultStmt(clang::DefaultStmt *stmt)
 {
     const auto current_caller_id = context().caller_id();
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         diagram().add_default_stmt(current_caller_id);
     }
 
@@ -809,7 +809,7 @@ bool translation_unit_visitor::TraverseConditionalOperator(
 {
     const auto current_caller_id = context().caller_id();
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().enter_conditionaloperator(stmt);
         diagram().add_conditional_stmt(current_caller_id);
     }
@@ -820,14 +820,14 @@ bool translation_unit_visitor::TraverseConditionalOperator(
     RecursiveASTVisitor<translation_unit_visitor>::TraverseStmt(
         stmt->getTrueExpr());
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         diagram().add_conditional_elsestmt(current_caller_id);
     }
 
     RecursiveASTVisitor<translation_unit_visitor>::TraverseStmt(
         stmt->getFalseExpr());
 
-    if (current_caller_id) {
+    if (current_caller_id != 0) {
         context().leave_conditionaloperator();
         diagram().end_conditional_stmt(current_caller_id);
     }
@@ -902,12 +902,12 @@ bool translation_unit_visitor::VisitCallExpr(clang::CallExpr *expr)
             callee_decl = expr->getDirectCallee();
         }
 
-        if (!callee_decl) {
+        if (callee_decl == nullptr) {
             //
             // Call to a method of a class template
             //
             if (clang::dyn_cast_or_null<clang::CXXDependentScopeMemberExpr>(
-                    expr->getCallee())) {
+                    expr->getCallee()) != nullptr) {
                 if (!process_class_template_method_call_expression(m, expr)) {
                     return true;
                 }
@@ -917,7 +917,7 @@ bool translation_unit_visitor::VisitCallExpr(clang::CallExpr *expr)
             // functions
             //
             else if (clang::dyn_cast_or_null<clang::UnresolvedLookupExpr>(
-                         expr->getCallee())) {
+                         expr->getCallee()) != nullptr) {
                 if (!process_unresolved_lookup_call_expression(m, expr))
                     return true;
             }
@@ -1000,9 +1000,10 @@ bool translation_unit_visitor::process_class_method_call_expression(
 
     std::string method_name = method_decl->getQualifiedNameAsString();
 
-    auto *callee_decl = method_decl ? method_decl->getParent() : nullptr;
+    auto *callee_decl =
+        method_decl != nullptr ? method_decl->getParent() : nullptr;
 
-    if (!callee_decl)
+    if (callee_decl == nullptr)
         return false;
 
     if (!should_include(callee_decl) || !should_include(method_decl))
@@ -1108,7 +1109,7 @@ bool translation_unit_visitor::process_function_call_expression(
 
     const auto *callee_function = callee_decl->getAsFunction();
 
-    if (!callee_function)
+    if (callee_function == nullptr)
         return false;
 
     if (!should_include(callee_function))
@@ -1147,9 +1148,10 @@ bool translation_unit_visitor::process_unresolved_lookup_call_expression(
     auto *unresolved_expr =
         clang::dyn_cast_or_null<clang::UnresolvedLookupExpr>(expr->getCallee());
 
-    if (unresolved_expr) {
+    if (unresolved_expr != nullptr) {
         for (const auto *decl : unresolved_expr->decls()) {
-            if (clang::dyn_cast_or_null<clang::FunctionTemplateDecl>(decl)) {
+            if (clang::dyn_cast_or_null<clang::FunctionTemplateDecl>(decl) !=
+                nullptr) {
                 // Yes, it's a template
                 auto *ftd =
                     clang::dyn_cast_or_null<clang::FunctionTemplateDecl>(decl);
@@ -1223,7 +1225,7 @@ translation_unit_visitor::create_class_declaration(clang::CXXRecordDecl *cls)
 
     const auto *parent = cls->getParent();
 
-    if (parent && parent->isRecord()) {
+    if ((parent != nullptr) && parent->isRecord()) {
         // Here we have 2 options, either:
         //  - the parent is a regular C++ class/struct
         //  - the parent is a class template declaration/specialization
@@ -1237,13 +1239,13 @@ translation_unit_visitor::create_class_declaration(clang::CXXRecordDecl *cls)
 
         // If not, check if the parent template declaration is in the model
         if (!id_opt &&
-            static_cast<const clang::RecordDecl *>(parent)
-                ->getDescribedTemplate()) {
+            (static_cast<const clang::RecordDecl *>(parent)
+                    ->getDescribedTemplate() != nullptr)) {
             local_id = static_cast<const clang::RecordDecl *>(parent)
                            ->getDescribedTemplate()
                            ->getID();
             if (static_cast<const clang::RecordDecl *>(parent)
-                    ->getDescribedTemplate())
+                    ->getDescribedTemplate() != nullptr)
                 id_opt = get_unique_id(local_id);
         }
 
@@ -1285,7 +1287,7 @@ translation_unit_visitor::create_class_declaration(clang::CXXRecordDecl *cls)
     }
     else if (cls->isLambda()) {
         c.is_lambda(true);
-        if (cls->getParent()) {
+        if (cls->getParent() != nullptr) {
             const auto type_name = make_lambda_name(cls);
 
             c.set_name(type_name);
@@ -1334,7 +1336,8 @@ bool translation_unit_visitor::process_template_parameters(
 
     for (const auto *parameter :
         *template_declaration.getTemplateParameters()) {
-        if (clang::dyn_cast_or_null<clang::TemplateTypeParmDecl>(parameter)) {
+        if (clang::dyn_cast_or_null<clang::TemplateTypeParmDecl>(parameter) !=
+            nullptr) {
             const auto *template_type_parameter =
                 clang::dyn_cast_or_null<clang::TemplateTypeParmDecl>(parameter);
             template_parameter ct;
@@ -1347,7 +1350,7 @@ bool translation_unit_visitor::process_template_parameters(
             c.add_template(std::move(ct));
         }
         else if (clang::dyn_cast_or_null<clang::NonTypeTemplateParmDecl>(
-                     parameter)) {
+                     parameter) != nullptr) {
             const auto *template_nontype_parameter =
                 clang::dyn_cast_or_null<clang::NonTypeTemplateParmDecl>(
                     parameter);
@@ -1361,7 +1364,7 @@ bool translation_unit_visitor::process_template_parameters(
             c.add_template(std::move(ct));
         }
         else if (clang::dyn_cast_or_null<clang::TemplateTemplateParmDecl>(
-                     parameter)) {
+                     parameter) != nullptr) {
             const auto *template_template_parameter =
                 clang::dyn_cast_or_null<clang::TemplateTemplateParmDecl>(
                     parameter);
@@ -1549,10 +1552,11 @@ void translation_unit_visitor::
 
     // If this is a nested template type - add nested templates as
     // template arguments
-    if (arg.getAsType()->getAs<clang::FunctionType>()) {
+    if (arg.getAsType()->getAs<clang::FunctionType>() != nullptr) {
         // TODO
     }
-    else if (arg.getAsType()->getAs<clang::TemplateSpecializationType>()) {
+    else if (arg.getAsType()->getAs<clang::TemplateSpecializationType>() !=
+        nullptr) {
         const auto *nested_template_type =
             arg.getAsType()->getAs<clang::TemplateSpecializationType>();
 
@@ -1571,7 +1575,7 @@ void translation_unit_visitor::
         simplify_system_template(
             argument, argument.to_string(config().using_namespace(), false));
     }
-    else if (arg.getAsType()->getAs<clang::TemplateTypeParmType>()) {
+    else if (arg.getAsType()->getAs<clang::TemplateTypeParmType>() != nullptr) {
         argument.is_template_parameter(true);
         argument.set_name(
             common::to_string(arg.getAsType(), template_decl->getASTContext()));
@@ -1637,7 +1641,8 @@ void translation_unit_visitor::process_template_specialization_argument(
 
         // If this is a nested template type - add nested templates as
         // template arguments
-        if (arg.getAsType()->getAs<clang::TemplateSpecializationType>()) {
+        if (arg.getAsType()->getAs<clang::TemplateSpecializationType>() !=
+            nullptr) {
             const auto *nested_template_type =
                 arg.getAsType()->getAs<clang::TemplateSpecializationType>();
 
@@ -1663,7 +1668,8 @@ void translation_unit_visitor::process_template_specialization_argument(
             simplify_system_template(argument,
                 argument.to_string(config().using_namespace(), false));
         }
-        else if (arg.getAsType()->getAs<clang::TemplateTypeParmType>()) {
+        else if (arg.getAsType()->getAs<clang::TemplateTypeParmType>() !=
+            nullptr) {
             auto type_name =
                 common::to_string(arg.getAsType(), cls->getASTContext());
 
@@ -1694,7 +1700,7 @@ void translation_unit_visitor::process_template_specialization_argument(
 
             argument.set_name(type_name);
         }
-        else if (arg.getAsType()->getAsCXXRecordDecl() &&
+        else if ((arg.getAsType()->getAsCXXRecordDecl() != nullptr) &&
             arg.getAsType()->getAsCXXRecordDecl()->isLambda()) {
             if (get_unique_id(arg.getAsType()->getAsCXXRecordDecl()->getID())
                     .has_value()) {
@@ -1816,8 +1822,8 @@ translation_unit_visitor::build_template_instantiation(
 
     auto *template_type_ptr = &template_type_decl;
     if (template_type_decl.isTypeAlias() &&
-        template_type_decl.getAliasedType()
-            ->getAs<clang::TemplateSpecializationType>())
+        (template_type_decl.getAliasedType()
+                ->getAs<clang::TemplateSpecializationType>() != nullptr))
         template_type_ptr = template_type_decl.getAliasedType()
                                 ->getAs<clang::TemplateSpecializationType>();
 
@@ -1841,8 +1847,9 @@ translation_unit_visitor::build_template_instantiation(
     auto *class_template_decl{
         clang::dyn_cast<clang::ClassTemplateDecl>(template_decl)};
 
-    if (class_template_decl && class_template_decl->getTemplatedDecl() &&
-        class_template_decl->getTemplatedDecl()->getParent() &&
+    if ((class_template_decl != nullptr) &&
+        (class_template_decl->getTemplatedDecl() != nullptr) &&
+        (class_template_decl->getTemplatedDecl()->getParent() != nullptr) &&
         class_template_decl->getTemplatedDecl()->getParent()->isRecord()) {
 
         common::model::namespace_ ns{
@@ -1895,7 +1902,8 @@ translation_unit_visitor::build_template_instantiation(
         clang::dyn_cast_or_null<clang::CXXRecordDecl>(
             template_decl->getTemplatedDecl());
 
-    if (templated_class_decl && templated_class_decl->hasDefinition())
+    if ((templated_class_decl != nullptr) &&
+        templated_class_decl->hasDefinition())
         for (const auto &base : templated_class_decl->bases()) {
             const auto base_class_name = common::to_string(
                 base.getType(), templated_class_decl->getASTContext(), false);
@@ -2124,7 +2132,7 @@ bool translation_unit_visitor::should_include(const clang::CallExpr *expr) const
     if (expr->isImplicitCXXThis())
         return false;
 
-    if (clang::dyn_cast_or_null<clang::ImplicitCastExpr>(expr))
+    if (clang::dyn_cast_or_null<clang::ImplicitCastExpr>(expr) != nullptr)
         return false;
 
     if (!context().valid())