diff --git a/.clang-tidy b/.clang-tidy
index 5ad3eea85..93deac3cb 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -31,3 +31,5 @@ Checks: '*,
 CheckOptions:
   - key: hicpp-special-member-functions.AllowSoleDefaultDtor
     value: 1
+
+HeaderFilterRegex: '.*nlohmann.*'
diff --git a/include/nlohmann/detail/iterators/iteration_proxy.hpp b/include/nlohmann/detail/iterators/iteration_proxy.hpp
index 3e181d5d9..1b47faeb3 100644
--- a/include/nlohmann/detail/iterators/iteration_proxy.hpp
+++ b/include/nlohmann/detail/iterators/iteration_proxy.hpp
@@ -39,7 +39,7 @@ template<typename IteratorType> class iteration_proxy_value
     /// a string representation of the array index
     mutable string_type array_index_str = "0";
     /// an empty string (to return a reference for primitive values)
-    const string_type empty_str;
+    const string_type empty_str{};
 
   public:
     explicit iteration_proxy_value(IteratorType it) noexcept : anchor(it) {}
diff --git a/test/src/unit-udt.cpp b/test/src/unit-udt.cpp
index 623d4bb2c..96398dbea 100644
--- a/test/src/unit-udt.cpp
+++ b/test/src/unit-udt.cpp
@@ -618,8 +618,8 @@ struct small_pod
 
 struct non_pod
 {
-    std::string s;
-    non_pod() : s() {}
+    std::string s{};
+    non_pod() = default;
     non_pod(std::string S) : s(std::move(S)) {}
 };