Fix CI failures on develop from the API performance stack

.github/workflows/windows.yml

@@ -166,19 +166,21 @@ jobs:
       # link, but the binaries clang 11.0.1 and clang 18.1.8 then produce crash
       # before doctest prints its first line - 39 of 102 tests on clang 18.
       # Keep the objects small by splitting the test files instead.
-      # Objects with more than 65535 sections fail to link with "relocation
-      # truncated to fit: IMAGE_REL_AMD64_REL32 against `.rdata'": the MinGW
-      # linker stores the section an associative COMDAT section belongs to in
-      # 16 bits (x_associated in binutils' include/coff/internal.h), so it
-      # discards the jump tables of inline functions together with the wrong
-      # function. Each basic_json specialization a test file instantiates adds
-      # many sections, so test a second one in a file of its own.
+      # The tests link with LLD: GNU ld fails on objects with more than 32767
+      # sections with "relocation truncated to fit: IMAGE_REL_AMD64_REL32
+      # against `.rdata'", as it stores the section an associative COMDAT
+      # section belongs to in 16 bits (x_associated in binutils'
+      # include/coff/internal.h) and so discards the jump tables of inline
+      # functions together with the wrong function. Each basic_json
+      # specialization and input type a test file instantiates adds many
+      # sections, so unit-msgpack.cpp and unit-regression2.cpp kept crossing
+      # that limit as the library grew.
       - name: Run CMake
         run: cmake -S . -B build ^
              -DCMAKE_CXX_COMPILER="C:/Program Files/LLVM/bin/clang++.exe" ^
              -DCMAKE_CXX_FLAGS="--target=x86_64-w64-mingw32 -stdlib=libstdc++ -pthread" ^
              -DCMAKE_CXX_FLAGS_DEBUG="-g0" ^
-             -DCMAKE_EXE_LINKER_FLAGS="-lwinpthread" ^
+             -DCMAKE_EXE_LINKER_FLAGS="-fuse-ld=lld -lwinpthread" ^
              -G"MinGW Makefiles" ^
              -DCMAKE_BUILD_TYPE=Debug ^
              -DJSON_BuildTests=On

include/nlohmann/detail/conversions/to_json.hpp

@@ -13,7 +13,7 @@
     #include <optional> // optional
 #endif
 
-#include <iterator> // begin, end
+#include <iterator> // begin, end, make_move_iterator, move_iterator
 #include <memory> // allocator_traits
 #include <string> //  basic_string, char_traits
 #include <tuple> // tuple, get
@@ -48,6 +48,32 @@ namespace detail
  * leave j with the type of the new value, but the pointer to the destroyed old one.
  */
 
+// a move iterator over the elements of an rvalue container, unless they are
+// const (e.g., std::set): libstdc++ before GCC 5 defines the reference of a
+// std::move_iterator as value_type&&, which cannot bind to a const element
+template<typename Iterator>
+std::move_iterator<Iterator> make_move_iterator_if_mutable_impl(const Iterator& it, std::true_type /*mutable*/)
+{
+    return std::make_move_iterator(it);
+}
+
+template<typename Iterator>
+Iterator make_move_iterator_if_mutable_impl(const Iterator& it, std::false_type /*mutable*/)
+{
+    return it;
+}
+
+template<typename Iterator>
+using is_mutable_iterator = std::integral_constant < bool,
+      !std::is_const<typename std::remove_reference<decltype(*std::declval<Iterator&>())>::type>::value >;
+
+template<typename Iterator>
+auto make_move_iterator_if_mutable(const Iterator& it)
+-> decltype(make_move_iterator_if_mutable_impl(it, is_mutable_iterator<Iterator> {}))
+{
+    return make_move_iterator_if_mutable_impl(it, is_mutable_iterator<Iterator> {});
+}
+
 template<value_t> struct external_constructor;
 
 template<>
@@ -174,7 +200,7 @@ struct external_constructor<value_t::array>
         using std::begin;
         using std::end;
 
-        const typename BasicJsonType::json_value value(j.template create<typename BasicJsonType::array_t>(std::make_move_iterator(begin(arr)), std::make_move_iterator(end(arr))));
+        const typename BasicJsonType::json_value value(j.template create<typename BasicJsonType::array_t>(make_move_iterator_if_mutable(begin(arr)), make_move_iterator_if_mutable(end(arr))));
         j.replace_value(value_t::array, value);
     }
 
@@ -235,7 +261,7 @@ struct external_constructor<value_t::object>
         using std::begin;
         using std::end;
 
-        const typename BasicJsonType::json_value value(j.template create<typename BasicJsonType::object_t>(std::make_move_iterator(begin(obj)), std::make_move_iterator(end(obj))));
+        const typename BasicJsonType::json_value value(j.template create<typename BasicJsonType::object_t>(make_move_iterator_if_mutable(begin(obj)), make_move_iterator_if_mutable(end(obj))));
         j.replace_value(value_t::object, value);
     }
 
@@ -413,25 +439,27 @@ using is_movable_container_rvalue = negation<disjunction<
                                     std::is_const<T>,
                                     has_dedicated_to_json<T>,
                                     is_basic_json<T>,
-                                    is_range_view_type<T>,
                                     is_enum_keyed_map_type<T>,
                                     std::is_same<T, std::vector<bool>>>>;
 
-// rvalue array-like containers
+// rvalue array-like containers; object types are ruled out before views are
+// checked, as std::ranges::view<T> for the object_t of an ordered_json would
+// need that ordered_json to be complete (GCC 11, see #3312)
 template<typename BasicJsonType, typename T>
 using is_rvalue_array_to_json = conjunction<is_movable_container_rvalue<T>,
+      negation<is_compatible_object_type<BasicJsonType, T>>,
+      negation<is_range_view_type<T>>,
       is_compatible_array_type<BasicJsonType, T>,
       negation<disjunction<
       std::is_same<T, typename BasicJsonType::array_t>,
       std::is_same<T, typename BasicJsonType::binary_t>,
-      is_compatible_object_type<BasicJsonType, T>,
       is_compatible_string_type<BasicJsonType, T>,
       is_compatible_binary_type<BasicJsonType, T>>>>;
 
 // rvalue containers: their elements are moved instead of copied
 template<typename BasicJsonType, typename CompatibleArrayType,
          enable_if_t<is_rvalue_array_to_json<BasicJsonType, CompatibleArrayType>::value, int> = 0>
-inline void to_json(BasicJsonType& j, CompatibleArrayType && arr)
+inline void to_json(BasicJsonType& j, CompatibleArrayType && arr) // NOLINT(cppcoreguidelines-missing-std-forward)
 {
     external_constructor<value_t::array>::construct_moving(j, arr);
 }
@@ -509,15 +537,16 @@ inline void to_json(BasicJsonType& j, const EnumKeyedMap& map)
 }
 #endif
 
-// rvalue object-like containers
+// rvalue object-like containers (views have no key_type and mapped_type, so
+// they are no compatible object type)
 template<typename BasicJsonType, typename T>
 using is_rvalue_object_to_json = conjunction<is_movable_container_rvalue<T>,
       negation<std::is_same<T, typename BasicJsonType::object_t>>,
       is_compatible_object_type<BasicJsonType, T>>;
 
 template<typename BasicJsonType, typename CompatibleObjectType,
          enable_if_t<is_rvalue_object_to_json<BasicJsonType, CompatibleObjectType>::value, int> = 0>
-inline void to_json(BasicJsonType& j, CompatibleObjectType && obj)
+inline void to_json(BasicJsonType& j, CompatibleObjectType && obj) // NOLINT(cppcoreguidelines-missing-std-forward)
 {
     external_constructor<value_t::object>::construct_moving(j, obj);
 }

include/nlohmann/detail/conversions/zmij.hpp

@@ -185,7 +185,7 @@ JSON_HEDLEY_ALWAYS_INLINE shortest_decimal to_shortest(std::uint64_t bits) noexc
     const uint128_parts p = umul192_hi128(p10.high, p10.low, bin_sig << static_cast<unsigned>(shift));
     std::uint64_t integral = p.high >> static_cast<unsigned>(extra_shift);
     // (no casts in the shifts: MSVC 2015 warns C4554 on them despite the parentheses)
-    constexpr unsigned fractional_low_shift = static_cast<unsigned>(extra_shift);
+    constexpr auto fractional_low_shift = static_cast<unsigned>(extra_shift);
     constexpr unsigned fractional_high_shift = 64u - fractional_low_shift;
     const std::uint64_t fractional = (p.high << fractional_high_shift) | (p.low >> fractional_low_shift);
     std::uint64_t digit = 0;

include/nlohmann/detail/exceptions.hpp

@@ -494,8 +494,7 @@ JSON_HEDLEY_NO_RETURN JSON_HEDLEY_NEVER_INLINE void throw_patch_missing_member(c
     static_cast<void>(string_type);
     static_cast<void>(val);
     // context-sensitive error message
-    const std::string error_msg = (op == "op") ? std::string("operation") : concat("operation '", op, '\'');
-    JSON_THROW(parse_error::create(exception_id::patch_invalid_operation, 0, concat(error_msg, string_type ? " must have string member '" : " must have member '", member, "'"), &val));
+    JSON_THROW(parse_error::create(exception_id::patch_invalid_operation, 0, concat((op == "op") ? std::string("operation") : concat("operation '", op, '\''), string_type ? " must have string member '" : " must have member '", member, "'"), &val));
 }
 
 template<typename StringType, typename BasicJsonType>

include/nlohmann/detail/iterators/iter_impl.hpp

@@ -680,12 +680,12 @@ class iter_impl // NOLINT(cppcoreguidelines-special-member-functions,hicpp-speci
     {
         JSON_ASSERT(m_object != nullptr);
 
-        if (JSON_HEDLEY_LIKELY(m_object->is_object()))
+        if (JSON_HEDLEY_UNLIKELY(!m_object->is_object()))
         {
-            return m_it.object_iterator->first;
+            throw_literal<invalid_iterator>(exception_id::iterator_key_not_object, "cannot use key() for non-object iterators", m_object);
         }
 
-        throw_literal<invalid_iterator>(exception_id::iterator_key_not_object, "cannot use key() for non-object iterators", m_object);
+        return m_it.object_iterator->first;
     }
 
     /*!

include/nlohmann/detail/json_pointer.hpp

@@ -11,6 +11,7 @@
 #include <algorithm> // all_of
 #include <cctype> // isdigit
 #include <cerrno> // errno, ERANGE
+#include <cstddef> // size_t
 #include <cstdlib> // strtoull
 #ifndef JSON_NO_IO
     #include <iosfwd> // ostream
@@ -334,7 +335,7 @@ class json_pointer
                 {
                     break; // not a plain number: let strtoull decide
                 }
-                acc = static_cast<size_type>(acc * 10 + static_cast<size_type>(c - '0'));
+                acc = static_cast<size_type>((acc * 10) + static_cast<size_type>(c - '0'));
                 if (JSON_HEDLEY_UNLIKELY(i == s.size() - 1))
                 {
                     idx = acc;
@@ -529,10 +530,10 @@ class json_pointer
 
         static std::size_t hash_of(std::size_t parent, const string_t& token) noexcept
         {
-            std::size_t h = parent * static_cast<std::size_t>(0x9E3779B97F4A7C15ULL);
+            std::size_t h = parent * static_cast<std::size_t>(0x9E3779B97F4A7C15ULL & (std::numeric_limits<std::size_t>::max)());
             for (std::size_t i = 0; i < token.size(); ++i)
             {
-                h = (h ^ static_cast<unsigned char>(token[i])) * static_cast<std::size_t>(0x100000001B3ULL);
+                h = (h ^ static_cast<unsigned char>(token[i])) * static_cast<std::size_t>(0x100000001B3ULL & (std::numeric_limits<std::size_t>::max)());
             }
             return h ^ (h >> 29u);
         }