diff --git a/iguana/define.h b/iguana/define.h
index ee0e3596..2887122c 100644
--- a/iguana/define.h
+++ b/iguana/define.h
@@ -1,9 +1,10 @@
 #pragma once
 
-#include <array>
-#if __cplusplus >= 202002L
+#if (defined(_MSC_VER) && _MSC_VER >= 1920 && _MSVC_LANG >= 202002L) || \
+    (!defined(_MSC_VER) && defined(__cplusplus) && __cplusplus >= 202002L)
 #include <bit>
 #endif
+#include <array>
 #include <string>
 #include <string_view>
 #include <type_traits>
diff --git a/iguana/json_util.hpp b/iguana/json_util.hpp
index 986040ef..5c00c077 100644
--- a/iguana/json_util.hpp
+++ b/iguana/json_util.hpp
@@ -90,16 +90,6 @@ IGUANA_INLINE void skip_ws_no_comments(It &&it, It &&end) {
   }
 }
 
-inline constexpr auto has_zero = [](uint64_t chunk) IGUANA__INLINE_LAMBDA {
-  return (((chunk - 0x0101010101010101) & ~chunk) & 0x8080808080808080);
-};
-
-inline constexpr auto has_qoute = [](uint64_t chunk) IGUANA__INLINE_LAMBDA {
-  return has_zero(
-      chunk ^
-      0b0010001000100010001000100010001000100010001000100010001000100010);
-};
-
 inline constexpr auto has_escape = [](uint64_t chunk) IGUANA__INLINE_LAMBDA {
   return has_zero(
       chunk ^
diff --git a/iguana/util.hpp b/iguana/util.hpp
index f1ecf9e7..b5ec2c3e 100644
--- a/iguana/util.hpp
+++ b/iguana/util.hpp
@@ -17,7 +17,6 @@
 #include "error_code.h"
 #include "reflection.hpp"
 
-
 namespace iguana {
 
 template <typename T>
@@ -194,4 +193,14 @@ IGUANA_INLINE void match(It &&it, It &&end) {
     }
 }
 
+inline constexpr auto has_zero = [](uint64_t chunk) IGUANA__INLINE_LAMBDA {
+  return (((chunk - 0x0101010101010101) & ~chunk) & 0x8080808080808080);
+};
+
+inline constexpr auto has_qoute = [](uint64_t chunk) IGUANA__INLINE_LAMBDA {
+  return has_zero(
+      chunk ^
+      0b0010001000100010001000100010001000100010001000100010001000100010);
+};
+
 }  // namespace iguana
diff --git a/iguana/xml_util.hpp b/iguana/xml_util.hpp
index be28c4d2..cd2df709 100644
--- a/iguana/xml_util.hpp
+++ b/iguana/xml_util.hpp
@@ -47,10 +47,6 @@ struct is_cdata_t<xml_cdata_t<T>> : std::true_type {};
 template <typename T>
 constexpr inline bool cdata_v = is_cdata_t<std::remove_cvref_t<T>>::value;
 
-inline constexpr auto has_zero = [](uint64_t chunk) IGUANA__INLINE_LAMBDA {
-  return (((chunk - 0x0101010101010101) & ~chunk) & 0x8080808080808080);
-};
-
 inline constexpr auto has_greater = [](uint64_t chunk) IGUANA__INLINE_LAMBDA {
   return has_zero(
       chunk ^
@@ -82,15 +78,9 @@ inline constexpr auto has_equal = [](uint64_t chunk) IGUANA__INLINE_LAMBDA {
       0b0011110100111101001111010011110100111101001111010011110100111101);
 };
 
-inline constexpr auto has_qoute = [](uint64_t chunk) IGUANA__INLINE_LAMBDA {
-  return has_zero(
-      chunk ^
-      0b0010001000100010001000100010001000100010001000100010001000100010);
-};
-
 template <typename It>
 IGUANA_INLINE void skip_sapces_and_newline(It &&it, It &&end) {
-  while (it != end && (*it < 33)) {
+  while (it != end && (static_cast<uint8_t>(*it) < 33)) {
     ++it;
   }
 }
diff --git a/iguana/yaml_util.hpp b/iguana/yaml_util.hpp
index 00e44461..0f2be370 100644
--- a/iguana/yaml_util.hpp
+++ b/iguana/yaml_util.hpp
@@ -6,7 +6,7 @@ namespace iguana {
 // return true when it==end
 template <typename It>
 IGUANA_INLINE bool skip_space_till_end(It &&it, It &&end) {
-  while (it != end && *it < 33) ++it;
+  while (it != end && (static_cast<uint8_t>(*it) < 33)) ++it;
   return it == end;
 }