Fixed compilation issues under U21.10

CMakeLists.txt

@@ -18,6 +18,8 @@ elseif(NOT "" STREQUAL "$ENV{Simox_BOOST_VERSION}")
     SET(Simox_BOOST_VERSION $ENV{Simox_BOOST_VERSION})
 elseif(RELEASE_CODENAME STREQUAL focal OR RELEASE_CODENAME STREQUAL odin)
     SET(Simox_BOOST_VERSION 1.71.0)
+elseif(RELEASE_CODENAME STREQUAL impish)
+    SET(Simox_BOOST_VERSION 1.74.0)
 else()
     SET(Simox_BOOST_VERSION 1.65.1)
 endif()

SimoxUtility/algorithm/string/string_tools.h

@@ -21,7 +21,7 @@
 
 #pragma once
 
-#include <string>
+#include <cstring>
 #include <sstream>
 #include <vector>
 #include <locale>

SimoxUtility/color/ColorMap.h

@@ -5,6 +5,7 @@
 #include <initializer_list>
 #include <map>
 #include <string>
+#include <optional>
 
 #include <SimoxUtility/algorithm/apply.hpp>
 #include <SimoxUtility/algorithm/minmax.h>

SimoxUtility/json/json.hpp

@@ -9627,7 +9627,7 @@ class binary_writer
     static CharType to_char_type(std::uint8_t x) noexcept
     {
         static_assert(sizeof(std::uint8_t) == sizeof(CharType), "size of CharType must be equal to std::uint8_t");
-        static_assert(std::is_pod<CharType>::value, "CharType must be POD");
+        static_assert(std::is_standard_layout_v<CharType> && std::is_trivial_v<CharType>, "CharType must be POD");
         CharType result;
         std::memcpy(&result, &x, sizeof(x));
         return result;