diff --git a/include/exiv2/photoshop.hpp b/include/exiv2/photoshop.hpp
index 31c420ad..4b140401 100644
--- a/include/exiv2/photoshop.hpp
+++ b/include/exiv2/photoshop.hpp
@@ -16,10 +16,10 @@ class IptcData;
 /// @brief Helper class, has methods to deal with %Photoshop "Information Resource Blocks" (IRBs).
 struct EXIV2API Photoshop {
   // Todo: Public for now
-  static constexpr std::array irbId_{"8BIM", "AgHg", "DCSR", "PHUT"};  //!< %Photoshop IRB markers
-  static constexpr auto ps3Id_ = "Photoshop 3.0\0";                    //!< %Photoshop marker
-  static constexpr uint16_t iptc_ = 0x0404;                            //!< %Photoshop IPTC marker
-  static constexpr uint16_t preview_ = 0x040c;                         //!< %Photoshop preview marker
+  static constexpr std::array<const char*, 4> irbId_{"8BIM", "AgHg", "DCSR", "PHUT"};  //!< %Photoshop IRB markers
+  static constexpr auto ps3Id_ = "Photoshop 3.0\0";                                    //!< %Photoshop marker
+  static constexpr uint16_t iptc_ = 0x0404;                                            //!< %Photoshop IPTC marker
+  static constexpr uint16_t preview_ = 0x040c;                                         //!< %Photoshop preview marker
 
   /// @brief Checks an IRB
   /// @param pPsData  Existing IRB buffer. It is expected to be of size 4.
diff --git a/include/exiv2/slice.hpp b/include/exiv2/slice.hpp
index 5cca6364..f278c7bc 100644
--- a/include/exiv2/slice.hpp
+++ b/include/exiv2/slice.hpp
@@ -263,7 +263,7 @@ struct ContainerStorage {
 
   using const_iterator = typename container::const_iterator;
 
-  using value_type = std::remove_cv_t<typename container::value_type>;
+  using value_type = typename std::remove_cv<typename container::value_type>::type;
 
   /*!
    * @throw std::out_of_range when end is larger than the container's
@@ -324,7 +324,7 @@ struct ContainerStorage {
  */
 template <typename storage_type>
 struct PtrSliceStorage {
-  using value_type = std::remove_cv_t<std::remove_pointer_t<storage_type>>;
+  using value_type = typename std::remove_cv<typename std::remove_pointer<storage_type>::type>::type;
   using iterator = value_type*;
   using const_iterator = const value_type*;
 
@@ -423,7 +423,7 @@ struct Slice : public Internal::MutableSliceBase<Internal::ContainerStorage, con
 
   using const_iterator = typename container::const_iterator;
 
-  using value_type = std::remove_cv_t<typename container::value_type>;
+  using value_type = typename std::remove_cv<typename container::value_type>::type;
 
   /*!
    * @brief Construct a slice of the container `cont` starting at `begin`
@@ -476,7 +476,7 @@ struct Slice<const container> : public Internal::ConstSliceBase<Internal::Contai
 
   using const_iterator = typename container::const_iterator;
 
-  using value_type = std::remove_cv_t<typename container::value_type>;
+  using value_type = typename std::remove_cv<typename container::value_type>::type;
 
   Slice(const container& cont, size_t begin, size_t end) :
       Internal::ConstSliceBase<Internal::ContainerStorage, const container>(cont, begin, end) {
diff --git a/include/exiv2/value.hpp b/include/exiv2/value.hpp
index 9cf37588..0c7c906e 100644
--- a/include/exiv2/value.hpp
+++ b/include/exiv2/value.hpp
@@ -1261,7 +1261,8 @@ class ValueType : public Value {
   //! Utility for toInt64, toUint32, etc.
   template <typename I>
   inline I rational_to_integer_helper(size_t n) const {
-    auto&& [a, b] = value_.at(n);
+    auto a = value_.at(n).first;
+    auto b = value_.at(n).second;
 
     // Protect against divide-by-zero.
     if (b <= 0) {
@@ -1269,16 +1270,16 @@ class ValueType : public Value {
     }
 
     // Check for integer overflow.
-    if (std::is_signed_v<I> == std::is_signed_v<decltype(a)>) {
+    if (std::is_signed<I>::value == std::is_signed<decltype(a)>::value) {
       // conversion does not change sign
       const auto imin = std::numeric_limits<I>::min();
       const auto imax = std::numeric_limits<I>::max();
       if (imax < b || a < imin || imax < a) {
         return 0;
       }
-    } else if (std::is_signed_v<I>) {
+    } else if (std::is_signed<I>::value) {
       // conversion is from unsigned to signed
-      const auto imax = std::make_unsigned_t<I>(std::numeric_limits<I>::max());
+      const auto imax = typename std::make_unsigned<I>::type(std::numeric_limits<I>::max());
       if (imax < b || imax < a) {
         return 0;
       }
@@ -1289,8 +1290,8 @@ class ValueType : public Value {
         return 0;
       }
       // Inputs are not negative so convert them to unsigned.
-      const auto a_u = std::make_unsigned_t<decltype(a)>(a);
-      const auto b_u = std::make_unsigned_t<decltype(b)>(b);
+      const auto a_u = typename std::make_unsigned<decltype(a)>::type(a);
+      const auto b_u = typename std::make_unsigned<decltype(b)>::type(b);
       if (imax < b_u || imax < a_u) {
         return 0;
       }