diff --git a/CMakeLists.txt b/CMakeLists.txt
index 46a4e8a..a192031 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.7.0)
-project(test_uuid)
+project(test_uuid CXX)
 
 include_directories(${CMAKE_SOURCE_DIR}/include)
 include_directories(${CMAKE_SOURCE_DIR}/catch)
diff --git a/include/uuid.h b/include/uuid.h
index 10d63e4..cccd57c 100644
--- a/include/uuid.h
+++ b/include/uuid.h
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <cstring>
 #include <string>
 #include <sstream>
 #include <iomanip>
@@ -282,6 +283,19 @@ namespace uuids
       reserved
    };
 
+   struct uuid_error : public std::runtime_error
+   {
+      explicit uuid_error(std::string_view message)
+         : std::runtime_error(message.data())
+      {
+      }
+
+      explicit uuid_error(char const * message)
+         : std::runtime_error(message)
+      {
+      }
+   };
+
    // indicated by a bit pattern in octet 6, marked with M in xxxxxxxx-xxxx-Mxxx-xxxx-xxxxxxxxxxxx
    enum class uuid_version
    {
@@ -443,7 +457,7 @@ namespace uuids
       using value_type = uint8_t;
 
    public:
-      constexpr uuid() noexcept = default;
+      constexpr uuid() noexcept : data({}) {};
 
       explicit uuid(gsl::span<value_type, 16> bytes)
       {
@@ -501,7 +515,7 @@ namespace uuids
       constexpr uuid_const_iterator begin() const noexcept { return uuid_const_iterator(&data[0], 0); }
       constexpr uuid_const_iterator end() const noexcept { return uuid_const_iterator(&data[0], 16); }
 
-      constexpr inline gsl::span<std::byte const, 16> as_bytes() const
+      inline gsl::span<std::byte const, 16> as_bytes() const
       {
          return gsl::span<std::byte const, 16>(reinterpret_cast<std::byte const*>(data.data()), 16);
       }
@@ -572,19 +586,6 @@ namespace uuids
       friend std::basic_ostream<Elem, Traits> & operator<<(std::basic_ostream<Elem, Traits> &s, uuid const & id);  
    };
 
-   struct uuid_error : public std::runtime_error
-   {
-      explicit uuid_error(std::string_view message)
-         : std::runtime_error(message.data())
-      {
-      }
-
-      explicit uuid_error(char const * message)
-         : std::runtime_error(message)
-      {
-      }
-   };
-
    inline bool operator== (uuid const& lhs, uuid const& rhs) noexcept
    {
       return lhs.data == rhs.data;
@@ -869,4 +870,4 @@ namespace std
          return static_cast<result_type>(hasher(uuids::to_string(uuid)));
       }
    };
-}
\ No newline at end of file
+}
diff --git a/test/test_uuid.cpp b/test/test_uuid.cpp
index 8e418b1..4387968 100644
--- a/test/test_uuid.cpp
+++ b/test/test_uuid.cpp
@@ -1,6 +1,7 @@
 #include "uuid.h"
 #include "catch.hpp"
 
+#include <cstring>
 #include <set>
 #include <unordered_set>
 #include <vector>
@@ -233,10 +234,10 @@ TEST_CASE("Test iterators", "[iter]")
 TEST_CASE("Test constexpr", "[const]")
 {
    constexpr uuid empty;
-   constexpr bool isnil = empty.is_nil();
-   constexpr size_t size = empty.size();
-   constexpr uuid_variant variant = empty.variant();
-   constexpr uuid_version version = empty.version();
+   [[maybe_unused]] constexpr bool isnil = empty.is_nil();
+   [[maybe_unused]] constexpr size_t size = empty.size();
+   [[maybe_unused]] constexpr uuids::uuid_variant variant = empty.variant();
+   [[maybe_unused]] constexpr uuid_version version = empty.version();
 }
 
 TEST_CASE("Test size", "[operators]")
@@ -288,4 +289,4 @@ TEST_CASE("Test as_bytes", "[ops]")
       REQUIRE(memcmp(view.data(), arr.data(), arr.size()) == 0);
    }
 
-}
\ No newline at end of file
+}