Re-enable portability-template-virtual-member-function; remove redundant forwards

.clang-tidy disabled three checks "to get the CI going" (#4489, 2024-11-13): portability-template-virtual-member-function, bugprone-use-after-move and its alias hicpp-invalid-access-moved. portability-template-virtual-member-function only flagged output_stream_adapter::write_character/write_characters; annotate both with NOLINT and re-enable the check. bugprone-use-after-move flagged several double forwards that have no effect at runtime: - from_json.hpp calls std::forward<BasicJsonType>(j).at(Idx) inside pack expansions; at() has no ref-qualified overloads and always returns an lvalue reference, so the forward is a no-op. Replace with plain j.at(Idx) in all four places. - the move constructor forwards the whole object to its base class and then reads other's members. That is item 9 of #5724 (together with its cppcheck suppressions) and is left to that change. - input_adapters.hpp forwards the container twice on purpose, so the begin/end iterator types match adapter_type; annotate with NOLINT and a comment instead of changing behavior. The check still flags the move constructor (see above) and two sites in at(KeyType&&) (both overloads, json.hpp, in the throw's string_t(std::forward<KeyType>(key)) after find(std::forward<KeyType>(key))). Open PR #5689 rewrites that hunk, so bugprone-use-after-move (and hicpp-invalid-access-moved) stay disabled for now, with a comment explaining why; re-enable them once #5689 and the #5724 move-constructor change have landed. Also resolve the portability-avoid-pragma-once TODO: single_include never has #pragma once (amalgamate.py strips it) and every supported compiler accepts it in include/, so keep it disabled with an explanatory comment instead of a TODO. Fix the stale "json.hpp, around line 1265" comment in unit-class_parser.cpp, which now points at the move constructor's actual line. Behavior, the public API and the ABI do not change. Verified with clang-tidy 22.1.8 that portability-template-virtual-member-function now reports nothing, that bugprone-use-after-move/ hicpp-invalid-access-moved report only the known at(KeyType&&) and move-constructor sites, and that unit-custom-base-class, unit-constructor1, unit-conversions, unit-element_access2, unit-class_parser and unit-diagnostic-positions (JSON_DIAGNOSTIC_POSITIONS=1) compile under ASan/UBSan and pass with the same assertion counts as before. Ran make amalgamate. Part of #5725 Signed-off-by: Niels Lohmann <mail@nlohmann.me>
Remove the no-op ci_clang_analyze target
2026-09-30 11:40:30 +00:00 · 2026-09-30 10:33:04 +02:00 · 2026-09-30 09:55:24 +02:00 · 2026-09-30 09:54:07 +02:00 · 2026-09-30 09:52:09 +02:00 · 2026-09-30 09:44:28 +02:00
29 changed files with 919 additions and 179 deletions
@@ -1,9 +1,15 @@
-# TODO: The first three checks are only removed to get the CI going. They have to be addressed at some point.
-# TODO: portability-avoid-pragma-once: should be fixed eventually
+# bugprone-use-after-move (hicpp-invalid-access-moved is its alias) still flags
+# the basic_json move constructor, which forwards the whole object to its base
+# class (#5724), and two forwards in the error-message construction of
+# at(KeyType&&) (json.hpp, both overloads: find(std::forward<KeyType>(key))
+# followed by string_t(std::forward<KeyType>(key)) in the throw), which #5689
+# rewrites. Re-enable both checks once those changes have landed.
+# portability-avoid-pragma-once: kept disabled on purpose. #pragma once is accepted
+# by every supported compiler, and tools/amalgamate/amalgamate.py strips it from
+# single_include, so there is nothing left to fix here.

 Checks: '*,

-         -portability-template-virtual-member-function,
         -bugprone-use-after-move,
         -hicpp-invalid-access-moved,

@@ -81,10 +81,10 @@ jobs:
    container: silkeh/clang:dev
    strategy:
      matrix:
-        target: [ci_test_clang, ci_clang_tidy, ci_test_clang_sanitizer, ci_clang_analyze, ci_single_binaries]
+        target: [ci_test_clang, ci_clang_tidy, ci_test_clang_sanitizer, ci_single_binaries]
    steps:
-      - name: Install git, clang-tools, iwyu (ci_single_binaries), and unzip
-        run: apt-get update ; apt-get install -y git clang-tools iwyu unzip
+      - name: Install git, iwyu (ci_single_binaries), and unzip
+        run: apt-get update ; apt-get install -y git iwyu unzip
      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          persist-credentials: false
@@ -69,7 +69,6 @@ message(STATUS "🔖 Valgrind ${VALGRIND_TOOL_VERSION} (${VALGRIND_TOOL})")
 find_program(GENHTML_TOOL NAMES genhtml)
 find_program(PLOG_CONVERTER_TOOL NAMES plog-converter)
 find_program(PVS_STUDIO_ANALYZER_TOOL NAMES pvs-studio-analyzer)
-find_program(SCAN_BUILD_TOOL NAMES scan-build-15 scan-build-14 scan-build-13 scan-build-12 scan-build-11 scan-build)

 # the individual source files
 file(GLOB_RECURSE SRC_FILES ${PROJECT_SOURCE_DIR}/include/nlohmann/*.hpp)
@@ -423,21 +422,6 @@ add_custom_target(ci_test_valgrind
    COMMENT "Compile and test with Valgrind"
 )

-###############################################################################
-# Check code with Clang Static Analyzer.
-###############################################################################
-
-set(CLANG_ANALYZER_CHECKS "fuchsia.HandleChecker,nullability.NullableDereferenced,nullability.NullablePassedToNonnull,nullability.NullableReturnedFromNonnull,optin.cplusplus.UninitializedObject,optin.cplusplus.VirtualCall,optin.mpi.MPI-Checker,optin.osx.OSObjectCStyleCast,optin.osx.cocoa.localizability.EmptyLocalizationContextChecker,optin.osx.cocoa.localizability.NonLocalizedStringChecker,optin.performance.GCDAntipattern,optin.performance.Padding,optin.portability.UnixAPI,security.FloatLoopCounter,security.insecureAPI.DeprecatedOrUnsafeBufferHandling,security.insecureAPI.bcmp,security.insecureAPI.bcopy,security.insecureAPI.bzero,security.insecureAPI.rand,security.insecureAPI.strcpy,valist.CopyToSelf,valist.Uninitialized,valist.Unterminated,webkit.NoUncountedMemberChecker,webkit.RefCntblBaseVirtualDtor,core.CallAndMessage,core.DivideZero,core.NonNullParamChecker,core.NullDereference,core.StackAddressEscape,core.UndefinedBinaryOperatorResult,core.VLASize,core.uninitialized.ArraySubscript,core.uninitialized.Assign,core.uninitialized.Branch,core.uninitialized.CapturedBlockVariable,core.uninitialized.UndefReturn,cplusplus.InnerPointer,cplusplus.Move,cplusplus.NewDelete,cplusplus.NewDeleteLeaks,cplusplus.PlacementNew,cplusplus.PureVirtualCall,deadcode.DeadStores,nullability.NullPassedToNonnull,nullability.NullReturnedFromNonnull,osx.API,osx.MIG,osx.NumberObjectConversion,osx.OSObjectRetainCount,osx.ObjCProperty,osx.SecKeychainAPI,osx.cocoa.AtSync,osx.cocoa.AutoreleaseWrite,osx.cocoa.ClassRelease,osx.cocoa.Dealloc,osx.cocoa.IncompatibleMethodTypes,osx.cocoa.Loops,osx.cocoa.MissingSuperCall,osx.cocoa.NSAutoreleasePool,osx.cocoa.NSError,osx.cocoa.NilArg,osx.cocoa.NonNilReturnValue,osx.cocoa.ObjCGenerics,osx.cocoa.RetainCount,osx.cocoa.RunLoopAutoreleaseLeak,osx.cocoa.SelfInit,osx.cocoa.SuperDealloc,osx.cocoa.UnusedIvars,osx.cocoa.VariadicMethodTypes,osx.coreFoundation.CFError,osx.coreFoundation.CFNumber,osx.coreFoundation.CFRetainRelease,osx.coreFoundation.containers.OutOfBounds,osx.coreFoundation.containers.PointerSizedValues,security.insecureAPI.UncheckedReturn,security.insecureAPI.decodeValueOfObjCType,security.insecureAPI.getpw,security.insecureAPI.gets,security.insecureAPI.mkstemp,security.insecureAPI.mktemp,security.insecureAPI.vfork,unix.API,unix.Malloc,unix.MallocSizeof,unix.MismatchedDeallocator,unix.Vfork,unix.cstring.BadSizeArg,unix.cstring.NullArg")
-
-add_custom_target(ci_clang_analyze
-    COMMAND CXX=${CLANG_TOOL} ${CMAKE_COMMAND}
-        -DCMAKE_BUILD_TYPE=Debug -GNinja
-        -DJSON_BuildTests=ON
-        -S${PROJECT_SOURCE_DIR} -B${PROJECT_BINARY_DIR}/build_clang_analyze
-    COMMAND cd ${PROJECT_BINARY_DIR}/build_clang_analyze && ${SCAN_BUILD_TOOL} -enable-checker ${CLANG_ANALYZER_CHECKS} --use-c++=${CLANG_TOOL} -analyze-headers -o ${PROJECT_BINARY_DIR}/report ninja
-    COMMENT "Check code with Clang Analyzer"
-)
-
 ###############################################################################
 # Check code with Cppcheck.
 ###############################################################################
@@ -80,8 +80,8 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
  the end of the file was not reached when `strict` was set to true
 - Throws [parse_error.112](../../home/exceptions.md#jsonexceptionparse_error112) if unsupported features from CBOR were
  used in the given input or if the input is not valid CBOR
- Throws [parse_error.113](../../home/exceptions.md#jsonexceptionparse_error113) if a string was expected as a map key,
-  but not found
+- Throws [parse_error.113](../../home/exceptions.md#jsonexceptionparse_error113) if a map key is not a string (keys of other
+  types are not supported, as JSON object keys are always strings) or a string is malformed

 ## Complexity

@@ -73,8 +73,8 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
  the end of the file was not reached when `strict` was set to true
 - Throws [parse_error.112](../../home/exceptions.md#jsonexceptionparse_error112) if unsupported features from
  MessagePack were used in the given input or if the input is not valid MessagePack
- Throws [parse_error.113](../../home/exceptions.md#jsonexceptionparse_error113) if a string was expected as a map key,
-  but not found
+- Throws [parse_error.113](../../home/exceptions.md#jsonexceptionparse_error113) if a map key is not a string (keys of other
+  types are not supported, as JSON object keys are always strings) or a string is malformed

 ## Complexity

@@ -60,11 +60,11 @@ measures that counter them. The measures are described in detail in [Quality ass
 |---------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------|
 | Out-of-bounds read/write ([CWE-125](https://cwe.mitre.org/data/definitions/125.html), [CWE-787](https://cwe.mitre.org/data/definitions/787.html)) | bounds checks on all reads from the input; AddressSanitizer and Valgrind on the test suite; OSS-Fuzz      |
 | Integer overflow ([CWE-190](https://cwe.mitre.org/data/definitions/190.html)) | UndefinedBehaviorSanitizer with integer overflow detection; Clang-Tidy; Cppcheck                 |
-| Use after free, double free ([CWE-416](https://cwe.mitre.org/data/definitions/416.html), [CWE-415](https://cwe.mitre.org/data/definitions/415.html)) | ownership of all memory by values; AddressSanitizer and Valgrind; Clang Static Analyzer          |
+| Use after free, double free ([CWE-416](https://cwe.mitre.org/data/definitions/416.html), [CWE-415](https://cwe.mitre.org/data/definitions/415.html)) | ownership of all memory by values; AddressSanitizer and Valgrind; Clang-Tidy (incl. Clang Static Analyzer checks) |
 | Memory leaks ([CWE-401](https://cwe.mitre.org/data/definitions/401.html)) | Valgrind (Memcheck) on the test suite                                                            |
 | Uncontrolled recursion ([CWE-674](https://cwe.mitre.org/data/definitions/674.html)) | iterative parser, binary readers, and destructor; bounded recursion in value operations; tests with deeply nested inputs |
 | Uncontrolled resource consumption ([CWE-400](https://cwe.mitre.org/data/definitions/400.html)) | allocations based on announced sizes are capped; OSS-Fuzz with memory limits                     |
-| Undefined behavior in general ([CWE-758](https://cwe.mitre.org/data/definitions/758.html)) | UndefinedBehaviorSanitizer; runtime assertions; Clang-Tidy, Cppcheck, Clang Static Analyzer, Infer |
+| Undefined behavior in general ([CWE-758](https://cwe.mitre.org/data/definitions/758.html)) | UndefinedBehaviorSanitizer; runtime assertions; Clang-Tidy (incl. Clang Static Analyzer checks), Cppcheck, Infer |

 In addition, every line of the library is covered by the unit tests, and all parsers are fuzz-tested around the clock
 by [OSS-Fuzz](https://github.com/google/oss-fuzz/tree/master/projects/json).
@@ -183,8 +183,8 @@ Note: Some modern features (like C++20 ranges or filesystem support) may be disa
        ```

 - [x] The code is checked with the latest [Cppcheck](https://cppcheck.sourceforge.io) with all warnings enabled.
- [x] The code is checked with the latest [Clang Static Analyzer](https://clang-analyzer.llvm.org) with 89 enabled
-  rules.
+- [x] The code is checked with the latest [Clang Static Analyzer](https://clang-analyzer.llvm.org) checks, run
+  through Clang-Tidy's `clang-analyzer-*` checks with warnings as errors.
 - [x] The code is checked with [Infer](https://fbinfer.com).
 - [x] The code is checked with [Codacy](https://app.codacy.com/gh/nlohmann/json/dashboard).

@@ -174,7 +174,20 @@ The library maps CBOR types to JSON value types as follows:

 !!! warning "Object keys"

-    CBOR allows map keys of any type, whereas JSON only allows strings as keys in object values. Therefore, CBOR maps with keys other than UTF-8 strings are rejected.
+    CBOR allows map keys of any type, whereas JSON only allows strings as keys in object values. Therefore, CBOR maps
+    with keys other than text strings (major type 3) are rejected with a
+    [`parse_error.113`](../../home/exceptions.md#jsonexceptionparse_error113) exception (or, with `allow_exceptions` set
+    to `false`, a discarded value) naming the type of the key that was found, for instance:
+
+    ```
+    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found an unsigned integer; last byte: 0x01
+    ```
+
+    This applies to the [SAX interface](../parsing/sax_interface.md) as well, as the key is read before it is passed
+    on. This is a deliberate restriction of the library's JSON value model, not an oversight: formats built on CBOR
+    maps with integer keys, such as COSE ([RFC 9052](https://www.rfc-editor.org/rfc/rfc9052.html)) or CWT
+    ([RFC 8392](https://www.rfc-editor.org/rfc/rfc8392.html)), cannot be read with this library and need a
+    general-purpose CBOR library instead.

 !!! warning "UTF-8 validation of text strings"

@@ -138,6 +138,21 @@ The library maps MessagePack types to JSON value types as follows:

    Any MessagePack output created by `to_msgpack` can be successfully parsed by `from_msgpack`.

+!!! warning "Object keys"
+
+    MessagePack allows map keys of any type, whereas JSON only allows strings as keys in object values. Like the
+    JSON-compatible [profile](https://github.com/msgpack/msgpack/blob/master/spec.md#profile) sketched in the
+    MessagePack specification, this library restricts map keys to `str` values. Maps with keys of any other type are
+    rejected with a [`parse_error.113`](../../home/exceptions.md#jsonexceptionparse_error113) exception (or, with
+    `allow_exceptions` set to `false`, a discarded value) naming the type of the key that was found, for instance:
+
+    ```
+    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack object key: only string keys are supported, but found nil; last byte: 0xC0
+    ```
+
+    This applies to the [SAX interface](../parsing/sax_interface.md) as well, as the key is read before it is passed
+    on. Such input needs a general-purpose MessagePack library instead.
+
 !!! warning "UTF-8 validation of string values"

    The MessagePack specification requires `str` values (`fixstr`, `str 8`, `str 16`, `str 32`) to be valid UTF-8.
@@ -343,13 +343,20 @@ A string could not be read from a [binary format](../features/binary_formats/ind
 string was read where one was required (for instance as a map key), the string's length specification is invalid, or
 the string's bytes are not valid UTF-8.

+CBOR and MessagePack allow map keys of any type, but JSON object keys are always strings. Maps with keys of any other
+type (for instance integers or `null`) are therefore not supported; see the notes on
+[CBOR](../features/binary_formats/cbor.md) and [MessagePack](../features/binary_formats/messagepack.md).
+
 !!! failure "Example messages"

    ```
-    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0xFF
+    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found an unsigned integer; last byte: 0x01
    ```
    ```
-    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack string: expected length specification (0xA0-0xBF, 0xD9-0xDB); last byte: 0xFF
+    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack object key: only string keys are supported, but found nil; last byte: 0xC0
+    ```
+    ```
+    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0x7C
    ```
    ```
    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing UBJSON char: byte after 'C' must be in range 0x00..0x7F; last byte: 0x82
@@ -353,7 +353,7 @@ template < typename BasicJsonType, typename T, std::size_t... Idx >
 std::array<T, sizeof...(Idx)> from_json_inplace_array_impl(BasicJsonType&& j,
                     identity_tag<std::array<T, sizeof...(Idx)>> /*unused*/, index_sequence<Idx...> /*unused*/)
 {
-    return { { std::forward<BasicJsonType>(j).at(Idx).template get<T>()... } };
+    return { { j.at(Idx).template get<T>()... } };
 }

 template < typename BasicJsonType, typename T, std::size_t N >
@@ -502,7 +502,7 @@ using tuple_type = std::tuple < decltype(from_json_tuple_get_impl(std::declval<B
 template<std::size_t PTagValue, typename... Args, typename BasicJsonType, std::size_t... Idx>
 tuple_type<PTagValue, BasicJsonType, Args...> from_json_tuple_impl_base(BasicJsonType&& j, index_sequence<Idx...> /*unused*/)
 {
-    return tuple_type<PTagValue, BasicJsonType, Args...>(from_json_tuple_get_impl(std::forward<BasicJsonType>(j).at(Idx), detail::identity_tag<Args> {}, detail::priority_tag<PTagValue> {})...);
+    return tuple_type<PTagValue, BasicJsonType, Args...>(from_json_tuple_get_impl(j.at(Idx), detail::identity_tag<Args> {}, detail::priority_tag<PTagValue> {})...);
 }

 template<std::size_t PTagValue, typename BasicJsonType>
@@ -514,8 +514,8 @@ std::tuple<> from_json_tuple_impl_base(BasicJsonType& /*unused*/, index_sequence
 template < typename BasicJsonType, class A1, class A2 >
 std::pair<A1, A2> from_json_tuple_impl(BasicJsonType&& j, identity_tag<std::pair<A1, A2>> /*unused*/, priority_tag<0> /*unused*/)
 {
-    return {std::forward<BasicJsonType>(j).at(0).template get<A1>(),
-            std::forward<BasicJsonType>(j).at(1).template get<A2>()};
+    return {j.at(0).template get<A1>(),
+            j.at(1).template get<A2>()};
 }

 template<typename BasicJsonType, typename A1, typename A2>
@@ -1324,6 +1324,80 @@ class binary_reader
        }
    }

+    /*!
+    @brief reads a CBOR object key
+
+    RFC 8949 allows any data item as a map key, but only strings have a
+    counterpart in JSON. A key of any other type is rejected with a message
+    naming that type, rather than the one @ref get_cbor_string gives for a
+    malformed string.
+
+    @param[out] result  created key
+
+    @return whether key creation completed
+    */
+    bool get_cbor_object_key(string_t& result)
+    {
+        // EOF and major type 3 (text string) are left to get_cbor_string
+        if (current == char_traits<char_type>::eof() || (static_cast<unsigned int>(current) & 0xE0u) == 0x60u)
+        {
+            return get_cbor_string(result);
+        }
+
+        const char* found = nullptr;
+        switch (static_cast<unsigned int>(current) >> 5u)
+        {
+            case 0:
+                found = "an unsigned integer";
+                break;
+            case 1:
+                found = "a negative integer";
+                break;
+            case 2:
+                found = "a byte string";
+                break;
+            case 4:
+                found = "an array";
+                break;
+            case 5:
+                found = "a map";
+                break;
+            case 6:
+                found = "a tag";
+                break;
+            default: // major type 7
+                switch (current)
+                {
+                    case 0xF4:
+                    case 0xF5:
+                        found = "a boolean";
+                        break;
+                    case 0xF6:
+                        found = "null";
+                        break;
+                    case 0xF7:
+                        found = "undefined";
+                        break;
+                    case 0xF9:
+                    case 0xFA:
+                    case 0xFB:
+                        found = "a floating-point number";
+                        break;
+                    case 0xFF:
+                        found = "a break stop code";
+                        break;
+                    default:
+                        found = "a simple value";
+                        break;
+                }
+                break;
+        }
+
+        auto last_token = get_token_string();
+        return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read,
+                                exception_message(input_format_t::cbor, concat("only string keys are supported, but found ", found, "; last byte: 0x", last_token), "object key"), nullptr));
+    }
+
    /*!
    @brief reads a definite-length CBOR byte array

@@ -1568,7 +1642,7 @@ class binary_reader
                if (top.is_object)
                {
                    key.clear();
-                    if (JSON_HEDLEY_UNLIKELY(!get_cbor_string(key) || !sax->key(key)))
+                    if (JSON_HEDLEY_UNLIKELY(!get_cbor_object_key(key) || !sax->key(key)))
                    {
                        return false;
                    }
@@ -2069,6 +2143,98 @@ class binary_reader
        }
    }

+    /*!
+    @brief reads a MessagePack object key
+
+    The MessagePack specification allows any type as a map key, but only
+    strings have a counterpart in JSON. A key of any other type is rejected
+    with a message naming that type, rather than the one @ref
+    get_msgpack_string gives for a malformed string.
+
+    @param[out] result  created key
+
+    @return whether key creation completed
+    */
+    bool get_msgpack_object_key(string_t& result)
+    {
+        const char* found = nullptr;
+        switch (current)
+        {
+            case 0xC0:
+                found = "nil";
+                break;
+            case 0xC2:
+            case 0xC3:
+                found = "a boolean";
+                break;
+            case 0xCA:
+            case 0xCB:
+                found = "a float";
+                break;
+            case 0xC4:
+            case 0xC5:
+            case 0xC6:
+                found = "a bin";
+                break;
+            case 0xC7:
+            case 0xC8:
+            case 0xC9:
+            case 0xD4:
+            case 0xD5:
+            case 0xD6:
+            case 0xD7:
+            case 0xD8:
+                found = "an ext";
+                break;
+            case 0xCC:
+            case 0xCD:
+            case 0xCE:
+            case 0xCF:
+            case 0xD0:
+            case 0xD1:
+            case 0xD2:
+            case 0xD3:
+                found = "an integer";
+                break;
+            case 0xDC:
+            case 0xDD:
+                found = "an array";
+                break;
+            case 0xDE:
+            case 0xDF:
+                found = "a map";
+                break;
+            default:
+                // fixint, fixmap, and fixarray; strings, EOF, and the unused
+                // byte 0xC1 are left to get_msgpack_string
+                if (current == char_traits<char_type>::eof())
+                {
+                    return get_msgpack_string(result);
+                }
+                if (current <= 0x7F || current >= 0xE0)
+                {
+                    found = "an integer";
+                }
+                else if (current <= 0x8F)
+                {
+                    found = "a map";
+                }
+                else if (current <= 0x9F)
+                {
+                    found = "an array";
+                }
+                else
+                {
+                    return get_msgpack_string(result);
+                }
+                break;
+        }
+
+        auto last_token = get_token_string();
+        return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read,
+                                exception_message(input_format_t::msgpack, concat("only string keys are supported, but found ", found, "; last byte: 0x", last_token), "object key"), nullptr));
+    }
+
    /*!
    @brief reads a MessagePack byte array

@@ -2231,7 +2397,7 @@ class binary_reader
                {
                    get();
                    key.clear();
-                    if (JSON_HEDLEY_UNLIKELY(!get_msgpack_string(key) || !sax->key(key)))
+                    if (JSON_HEDLEY_UNLIKELY(!get_msgpack_object_key(key) || !sax->key(key)))
                    {
                        return false;
                    }
@@ -763,6 +763,9 @@ struct container_input_adapter_factory< ContainerType,

           static adapter_type create(ContainerType&& container)
 {
+    // container is forwarded twice on purpose: the resulting begin/end
+    // iterator types must match adapter_type, computed the same way
+    // NOLINTNEXTLINE(bugprone-use-after-move)
    return input_adapter(begin(std::forward<ContainerType>(container)), end(std::forward<ContainerType>(container)));
 }
       };
@@ -206,7 +206,6 @@ class lexer : public lexer_base<BasicJsonType>
    explicit lexer(InputAdapterType&& adapter, bool ignore_comments_ = false, bool discard_number_values_ = false) noexcept
        : ia(std::move(adapter))
        , ignore_comments(ignore_comments_)
-        , decimal_point_char(static_cast<char_int_type>(get_decimal_point()))
        , discard_number_values(discard_number_values_)
    {}

@@ -222,8 +221,7 @@ class lexer : public lexer_base<BasicJsonType>
    // locales
    /////////////////////

-    /// return the locale-dependent decimal point
-    JSON_HEDLEY_PURE
+    /// return the decimal point of the current locale
    static char get_decimal_point() noexcept
    {
        const auto* loc = localeconv();
@@ -1092,9 +1090,10 @@ class lexer : public lexer_base<BasicJsonType>
            token_type::value_float if number could be successfully scanned,
            token_type::parse_error otherwise

-    @note The scanner is independent of the current locale. Internally, the
-          locale's decimal point is used instead of `.` to work with the
-          locale-dependent converters.
+    @note The scanner is independent of the current locale: token_buffer
+          always holds `.`. Only the std::strtod fallback of convert_number()
+          depends on the locale, and it looks up the decimal point right
+          before converting (see convert_float_locale_aware()).
    */
    token_type scan_number()  // lgtm [cpp/use-of-goto] `goto` is used in this function to implement the number-parsing state machine described above. By design, any finite input will eventually reach the "done" state or return token_type::parse_error. In each intermediate state, 1 byte of the input is appended to the token_buffer vector, and only the already initialized variables token_buffer, number_type, and error_message are manipulated.
    {
@@ -1183,7 +1182,7 @@ scan_number_zero:
        {
            case '.':
            {
-                add(decimal_point_char);
+                add(current);
                decimal_point_position = token_buffer.size() - 1;
                goto scan_number_decimal1;
            }
@@ -1220,7 +1219,7 @@ scan_number_any1:

            case '.':
            {
-                add(decimal_point_char);
+                add(current);
                decimal_point_position = token_buffer.size() - 1;
                goto scan_number_decimal1;
            }
@@ -1462,9 +1461,9 @@ scan_number_done:

        // Only a number below 1 can carry further insignificant zeros, and only
        // while the count stays at the limit does removing them change the
-        // answer - so this loop is skipped for all but a few tokens. Note
-        // token_buffer holds the locale's decimal point, so the fraction is
-        // located through decimal_point_position rather than by searching '.'.
+        // answer - so this loop is skipped for all but a few tokens. The
+        // fraction is located through decimal_point_position rather than by
+        // searching '.'.
        if (lead_zero != 0)
        {
            JSON_ASSERT(has_dot != 0); // an integer "0" cannot reach the limit
@@ -1482,8 +1481,8 @@ scan_number_done:
    @brief convert the number text in token_buffer to its value and token type

    The digit sequence in token_buffer has already been validated (by the
-    scan_number() state machine or by the contiguous fast path) and holds the
-    locale decimal point in place of '.'. Integers are parsed first and fall
+    scan_number() state machine or by the contiguous fast path) and holds '.'
+    as decimal point, independent of the locale. Integers are parsed first and fall
    back to floating point on overflow. This is shared so both scanners produce
    identical results.

@@ -1563,7 +1562,7 @@ scan_number_done:
        // integer conversion above overflowed. Prefer std::from_chars
        // (Eisel-Lemire, locale-independent, correctly rounded) when available;
        // otherwise the exact Clinger fast path (double only); otherwise the
-        // locale-aware strtof/strtod.
+        // locale-aware strtof/strtod/strtold.
        if (parse_float_from_chars(num_begin, num_end, value_float))
        {
            return token_type::value_float;
@@ -1572,26 +1571,75 @@ scan_number_done:
        // extra pass over the token's bytes, which otherwise shows up on
        // high-precision inputs such as canada.json
        if (mantissa_fits_clinger(mantissa_end)
-                && parse_float_fast(num_begin, num_end, decimal_point_char, value_float))
+                && parse_float_fast(num_begin, num_end, value_float))
        {
            return token_type::value_float;
        }

-        char* endptr = nullptr; // NOLINT(misc-const-correctness,cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-        strtof(value_float, token_buffer.data(), &endptr);
-
-        // we checked the number format before
-        JSON_ASSERT(endptr == token_buffer.data() + token_buffer.size());
-
+        convert_float_locale_aware();
        return token_type::value_float;
    }

+    /*!
+    @brief convert the float in token_buffer with strtof/strtod/strtold
+
+    These functions expect the decimal point of the *current* locale, so it is
+    looked up right before the conversion instead of once when the lexer is
+    constructed: a locale change in between (by a parser callback, a SAX
+    handler, or another thread) must not truncate the value (#5198). The
+    token has been validated before, so if the conversion stops early and the
+    decimal point changed in the meantime, the locale changed between the
+    lookup and the call, and the conversion is repeated with the new decimal
+    point. If the decimal point did not change, a retry cannot succeed: the
+    locale's decimal point is not a single character (e.g., the two-byte
+    U+066B of ar_EG.UTF-8 or fa_IR.UTF-8) and cannot be substituted in place.
+    The value strtod parsed up to that point is kept, as before this change.
+
+    Note that changing the locale in another thread *while* strtod runs is
+    undefined behavior of the C library, which this function cannot prevent.
+    */
+    void convert_float_locale_aware()
+    {
+        const bool has_dot = decimal_point_position != std::string::npos;
+        char decimal_point = get_decimal_point();
+        for (;;)
+        {
+            const bool substitute = has_dot && decimal_point != '.';
+            if (substitute)
+            {
+                token_buffer[decimal_point_position] = static_cast<typename string_t::value_type>(decimal_point);
+            }
+
+            char* endptr = nullptr; // NOLINT(misc-const-correctness,cppcoreguidelines-pro-type-vararg,hicpp-vararg)
+            strtof(value_float, token_buffer.data(), &endptr);
+
+            if (substitute)
+            {
+                // get_string() hands the token to the SAX interface with '.'
+                token_buffer[decimal_point_position] = '.';
+            }
+
+            if (JSON_HEDLEY_LIKELY(endptr == token_buffer.data() + token_buffer.size()))
+            {
+                return;
+            }
+
+            // retry only if the locale changed; otherwise, this would loop forever
+            const char current_decimal_point = get_decimal_point();
+            if (current_decimal_point == decimal_point)
+            {
+                return;
+            }
+            decimal_point = current_decimal_point;
+        }
+    }
+
    /*!
    @brief contiguous fast path for scanning a number

    Parses the whole number token straight from the input buffer, avoiding the
    per-character get()/add() of scan_number(). On success it fills token_buffer
-    (with the locale decimal point substituted, as scan_number() does) and
+    (as scan_number() does) and
    returns the token type. On anything it does not fully recognize as a
    well-formed number it makes no state change and returns
    token_type::uninitialized, so the caller falls back to scan_number(), which
@@ -1707,16 +1755,11 @@ scan_number_done:
        }
 #endif

-        // materialize the token exactly as scan_number() would, substituting the
-        // locale decimal point so convert_number()'s strtof fallback stays valid.
-        // reset() already cleared token_buffer, so append() fills it (assign() is
-        // avoided because custom string_t types need not provide it)
+        // materialize the token exactly as scan_number() would. reset() already
+        // cleared token_buffer, so append() fills it (assign() is avoided
+        // because custom string_t types need not provide it)
        token_buffer.append(reinterpret_cast<const typename string_t::value_type*>(data), len);
-        if (dot_index != std::string::npos)
-        {
-            token_buffer[dot_index] = static_cast<typename string_t::value_type>(decimal_point_char);
-            decimal_point_position = dot_index;
-        }
+        decimal_point_position = dot_index;

        ia.bulk_skip(len - 1);
        position.chars_read_total += (len - 1);
@@ -1983,11 +2026,7 @@ scan_number_done:
    /// return current string value (implicitly resets the token; useful only once)
    string_t& get_string()
    {
-        // translate decimal points from locale back to '.' (#4084)
-        if (decimal_point_char != '.' && decimal_point_position != std::string::npos)
-        {
-            token_buffer[decimal_point_position] = '.';
-        }
+        // a number token holds '.' regardless of the locale (#4084)
        return token_buffer;
    }

@@ -2283,9 +2322,7 @@ scan_number_done:
    number_unsigned_t value_unsigned = 0;
    number_float_t value_float = 0;

-    /// the decimal point
-    const char_int_type decimal_point_char = '.';
-    /// the position of the decimal point in the input
+    /// the position of the decimal point in token_buffer
    std::size_t decimal_point_position = std::string::npos;

    /// whether the caller (e.g. accept()/json_sax_acceptor) only needs the
@@ -118,14 +118,12 @@ std::strtod. The parser only activates for number_float_t == double; float and
 long double keep the std::strtof/std::strtold paths (see the templated overload
 below).

-@param[in]  first          pointer to the first character of the number
-@param[in]  last           pointer past the last character
-@param[in]  decimal_point  the (locale-dependent) decimal point character
-@param[out] out            the parsed value on success
+@param[in]  first  pointer to the first character of the number
+@param[in]  last   pointer past the last character
+@param[out] out    the parsed value on success
@return true if the value was parsed exactly; false to fall back to strtod
 */
-template<typename DecimalPointType>
-bool parse_float_fast(const char* first, const char* last, DecimalPointType decimal_point, double& out) noexcept
+inline bool parse_float_fast(const char* first, const char* last, double& out) noexcept
 {
 #if defined(FLT_EVAL_METHOD) && FLT_EVAL_METHOD != 0
    // Clinger's fast path is only exact when double operations are evaluated in
@@ -136,7 +134,6 @@ bool parse_float_fast(const char* first, const char* last, DecimalPointType deci
    // std::from_chars / std::strtod path.
    static_cast<void>(first);
    static_cast<void>(last);
-    static_cast<void>(decimal_point);
    static_cast<void>(out);
    return false;
 #else
@@ -175,7 +172,7 @@ bool parse_float_fast(const char* first, const char* last, DecimalPointType deci
            ++num_digits;
            fractional_digits += static_cast<int>(seen_dot);
        }
-        else if (static_cast<DecimalPointType>(c) == decimal_point)
+        else if (c == '.')
        {
            if (JSON_HEDLEY_UNLIKELY(seen_dot))
            {
@@ -260,8 +257,8 @@ bool parse_float_fast(const char* first, const char* last, DecimalPointType deci
 }

 /// fast float path is only exact for `double`; decline for float/long double
-template<typename DecimalPointType, typename FloatType>
-bool parse_float_fast(const char* /*first*/, const char* /*last*/, DecimalPointType /*decimal_point*/, FloatType& /*out*/) noexcept
+template<typename FloatType>
+bool parse_float_fast(const char* /*first*/, const char* /*last*/, FloatType& /*out*/) noexcept
 {
    return false;
 }
@@ -273,9 +270,7 @@ std::from_chars is locale-independent, correctly rounded, and - via the
 Eisel-Lemire algorithm in modern standard libraries - much faster than strtod
 over the whole value range (not just the Clinger subset). It is used only when
 __cpp_lib_to_chars indicates full floating-point support and only when it
-consumes the entire token ([first, last)); a partial parse means the buffer
-uses a non-'.' locale decimal point, in which case the caller falls back to the
-locale-aware path. An under-/overflow (result_out_of_range) also declines, so
+consumes the entire token ([first, last)). An under-/overflow (result_out_of_range) also declines, so
 the caller's strtod fallback supplies the well-defined ±inf/0 result the parser
 expects (side-stepping the P4168 divergence between implementations).

@@ -277,11 +277,11 @@ class json_pointer
            JSON_THROW(detail::out_of_range::create(404, detail::concat("unresolved reference token '", s, "'"), nullptr));
        }

-        // only triggered on special platforms (like 32bit), see also
-        // https://github.com/nlohmann/json/pull/2203
+        // the index does not fit into size_type; on 64-bit platforms this is
+        // only SIZE_MAX itself (see #2203 and #5395)
        if (res >= static_cast<unsigned long long>((std::numeric_limits<size_type>::max)()))  // NOLINT(runtime/int)
        {
-            JSON_THROW(detail::out_of_range::create(410, detail::concat("array index ", s, " exceeds size_type"), nullptr));   // LCOV_EXCL_LINE
+            JSON_THROW(detail::out_of_range::create(410, detail::concat("array index ", s, " exceeds size_type"), nullptr));
        }

        return static_cast<size_type>(res);
@@ -260,7 +260,7 @@
    {                                                                                           \
        /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
-        /* NOLINTNEXTLINE(modernize-avoid-c-arrays) we don't want to depend on <array> */       \
+        /* NOLINTNEXTLINE(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) we don't want to depend on <array> */ \
        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                     \
        auto it = std::find_if(std::begin(m), std::end(m),                                      \
                               [e](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool  \
@@ -274,7 +274,7 @@
    {                                                                                           \
        /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
-        /* NOLINTNEXTLINE(modernize-avoid-c-arrays) we don't want to depend on <array> */       \
+        /* NOLINTNEXTLINE(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) we don't want to depend on <array> */ \
        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                     \
        auto it = std::find_if(std::begin(m), std::end(m),                                      \
                               [&j](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool \
@@ -313,7 +313,7 @@ void templated_json_throw(ExceptionType exception)
    {                                                                                           \
        /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
-        /* NOLINTNEXTLINE(modernize-avoid-c-arrays) we don't want to depend on <array> */       \
+        /* NOLINTNEXTLINE(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) we don't want to depend on <array> */ \
        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                     \
        auto it = std::find_if(std::begin(m), std::end(m),                                      \
                               [e](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool  \
@@ -328,7 +328,7 @@ void templated_json_throw(ExceptionType exception)
    {                                                                                           \
        /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
-        /* NOLINTNEXTLINE(modernize-avoid-c-arrays) we don't want to depend on <array> */       \
+        /* NOLINTNEXTLINE(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) we don't want to depend on <array> */ \
        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                     \
        auto it = std::find_if(std::begin(m), std::end(m),                                      \
                               [&j](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool \
@@ -117,12 +117,14 @@ class output_stream_adapter : public output_adapter_protocol<CharType>
        : stream(s)
    {}

+    // NOLINTNEXTLINE(portability-template-virtual-member-function)
    void write_character(CharType c) override
    {
        stream.put(c);
    }

    JSON_HEDLEY_NON_NULL(2)
+    // NOLINTNEXTLINE(portability-template-virtual-member-function)
    void write_characters(const CharType* s, std::size_t length) override
    {
        stream.write(s, static_cast<std::streamsize>(length));
@@ -2671,7 +2671,7 @@ JSON_HEDLEY_DIAGNOSTIC_POP
    {                                                                                           \
        /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
-        /* NOLINTNEXTLINE(modernize-avoid-c-arrays) we don't want to depend on <array> */       \
+        /* NOLINTNEXTLINE(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) we don't want to depend on <array> */ \
        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                     \
        auto it = std::find_if(std::begin(m), std::end(m),                                      \
                               [e](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool  \
@@ -2685,7 +2685,7 @@ JSON_HEDLEY_DIAGNOSTIC_POP
    {                                                                                           \
        /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
-        /* NOLINTNEXTLINE(modernize-avoid-c-arrays) we don't want to depend on <array> */       \
+        /* NOLINTNEXTLINE(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) we don't want to depend on <array> */ \
        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                     \
        auto it = std::find_if(std::begin(m), std::end(m),                                      \
                               [&j](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool \
@@ -2724,7 +2724,7 @@ void templated_json_throw(ExceptionType exception)
    {                                                                                           \
        /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
-        /* NOLINTNEXTLINE(modernize-avoid-c-arrays) we don't want to depend on <array> */       \
+        /* NOLINTNEXTLINE(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) we don't want to depend on <array> */ \
        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                     \
        auto it = std::find_if(std::begin(m), std::end(m),                                      \
                               [e](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool  \
@@ -2739,7 +2739,7 @@ void templated_json_throw(ExceptionType exception)
    {                                                                                           \
        /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
-        /* NOLINTNEXTLINE(modernize-avoid-c-arrays) we don't want to depend on <array> */       \
+        /* NOLINTNEXTLINE(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) we don't want to depend on <array> */ \
        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                     \
        auto it = std::find_if(std::begin(m), std::end(m),                                      \
                               [&j](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool \
@@ -5850,7 +5850,7 @@ template < typename BasicJsonType, typename T, std::size_t... Idx >
 std::array<T, sizeof...(Idx)> from_json_inplace_array_impl(BasicJsonType&& j,
                     identity_tag<std::array<T, sizeof...(Idx)>> /*unused*/, index_sequence<Idx...> /*unused*/)
 {
-    return { { std::forward<BasicJsonType>(j).at(Idx).template get<T>()... } };
+    return { { j.at(Idx).template get<T>()... } };
 }

 template < typename BasicJsonType, typename T, std::size_t N >
@@ -5999,7 +5999,7 @@ using tuple_type = std::tuple < decltype(from_json_tuple_get_impl(std::declval<B
 template<std::size_t PTagValue, typename... Args, typename BasicJsonType, std::size_t... Idx>
 tuple_type<PTagValue, BasicJsonType, Args...> from_json_tuple_impl_base(BasicJsonType&& j, index_sequence<Idx...> /*unused*/)
 {
-    return tuple_type<PTagValue, BasicJsonType, Args...>(from_json_tuple_get_impl(std::forward<BasicJsonType>(j).at(Idx), detail::identity_tag<Args> {}, detail::priority_tag<PTagValue> {})...);
+    return tuple_type<PTagValue, BasicJsonType, Args...>(from_json_tuple_get_impl(j.at(Idx), detail::identity_tag<Args> {}, detail::priority_tag<PTagValue> {})...);
 }

 template<std::size_t PTagValue, typename BasicJsonType>
@@ -6011,8 +6011,8 @@ std::tuple<> from_json_tuple_impl_base(BasicJsonType& /*unused*/, index_sequence
 template < typename BasicJsonType, class A1, class A2 >
 std::pair<A1, A2> from_json_tuple_impl(BasicJsonType&& j, identity_tag<std::pair<A1, A2>> /*unused*/, priority_tag<0> /*unused*/)
 {
-    return {std::forward<BasicJsonType>(j).at(0).template get<A1>(),
-            std::forward<BasicJsonType>(j).at(1).template get<A2>()};
+    return {j.at(0).template get<A1>(),
+            j.at(1).template get<A2>()};
 }

 template<typename BasicJsonType, typename A1, typename A2>
@@ -8307,6 +8307,9 @@ struct container_input_adapter_factory< ContainerType,

           static adapter_type create(ContainerType&& container)
 {
+    // container is forwarded twice on purpose: the resulting begin/end
+    // iterator types must match adapter_type, computed the same way
+    // NOLINTNEXTLINE(bugprone-use-after-move)
    return input_adapter(begin(std::forward<ContainerType>(container)), end(std::forward<ContainerType>(container)));
 }
       };
@@ -8605,14 +8608,12 @@ std::strtod. The parser only activates for number_float_t == double; float and
 long double keep the std::strtof/std::strtold paths (see the templated overload
 below).

-@param[in]  first          pointer to the first character of the number
-@param[in]  last           pointer past the last character
-@param[in]  decimal_point  the (locale-dependent) decimal point character
-@param[out] out            the parsed value on success
+@param[in]  first  pointer to the first character of the number
+@param[in]  last   pointer past the last character
+@param[out] out    the parsed value on success
@return true if the value was parsed exactly; false to fall back to strtod
 */
-template<typename DecimalPointType>
-bool parse_float_fast(const char* first, const char* last, DecimalPointType decimal_point, double& out) noexcept
+inline bool parse_float_fast(const char* first, const char* last, double& out) noexcept
 {
 #if defined(FLT_EVAL_METHOD) && FLT_EVAL_METHOD != 0
    // Clinger's fast path is only exact when double operations are evaluated in
@@ -8623,7 +8624,6 @@ bool parse_float_fast(const char* first, const char* last, DecimalPointType deci
    // std::from_chars / std::strtod path.
    static_cast<void>(first);
    static_cast<void>(last);
-    static_cast<void>(decimal_point);
    static_cast<void>(out);
    return false;
 #else
@@ -8662,7 +8662,7 @@ bool parse_float_fast(const char* first, const char* last, DecimalPointType deci
            ++num_digits;
            fractional_digits += static_cast<int>(seen_dot);
        }
-        else if (static_cast<DecimalPointType>(c) == decimal_point)
+        else if (c == '.')
        {
            if (JSON_HEDLEY_UNLIKELY(seen_dot))
            {
@@ -8747,8 +8747,8 @@ bool parse_float_fast(const char* first, const char* last, DecimalPointType deci
 }

 /// fast float path is only exact for `double`; decline for float/long double
-template<typename DecimalPointType, typename FloatType>
-bool parse_float_fast(const char* /*first*/, const char* /*last*/, DecimalPointType /*decimal_point*/, FloatType& /*out*/) noexcept
+template<typename FloatType>
+bool parse_float_fast(const char* /*first*/, const char* /*last*/, FloatType& /*out*/) noexcept
 {
    return false;
 }
@@ -8760,9 +8760,7 @@ std::from_chars is locale-independent, correctly rounded, and - via the
 Eisel-Lemire algorithm in modern standard libraries - much faster than strtod
 over the whole value range (not just the Clinger subset). It is used only when
 __cpp_lib_to_chars indicates full floating-point support and only when it
-consumes the entire token ([first, last)); a partial parse means the buffer
-uses a non-'.' locale decimal point, in which case the caller falls back to the
-locale-aware path. An under-/overflow (result_out_of_range) also declines, so
+consumes the entire token ([first, last)). An under-/overflow (result_out_of_range) also declines, so
 the caller's strtod fallback supplies the well-defined ±inf/0 result the parser
 expects (side-stepping the P4168 divergence between implementations).

@@ -9303,7 +9301,6 @@ class lexer : public lexer_base<BasicJsonType>
    explicit lexer(InputAdapterType&& adapter, bool ignore_comments_ = false, bool discard_number_values_ = false) noexcept
        : ia(std::move(adapter))
        , ignore_comments(ignore_comments_)
-        , decimal_point_char(static_cast<char_int_type>(get_decimal_point()))
        , discard_number_values(discard_number_values_)
    {}

@@ -9319,8 +9316,7 @@ class lexer : public lexer_base<BasicJsonType>
    // locales
    /////////////////////

-    /// return the locale-dependent decimal point
-    JSON_HEDLEY_PURE
+    /// return the decimal point of the current locale
    static char get_decimal_point() noexcept
    {
        const auto* loc = localeconv();
@@ -10189,9 +10185,10 @@ class lexer : public lexer_base<BasicJsonType>
            token_type::value_float if number could be successfully scanned,
            token_type::parse_error otherwise

-    @note The scanner is independent of the current locale. Internally, the
-          locale's decimal point is used instead of `.` to work with the
-          locale-dependent converters.
+    @note The scanner is independent of the current locale: token_buffer
+          always holds `.`. Only the std::strtod fallback of convert_number()
+          depends on the locale, and it looks up the decimal point right
+          before converting (see convert_float_locale_aware()).
    */
    token_type scan_number()  // lgtm [cpp/use-of-goto] `goto` is used in this function to implement the number-parsing state machine described above. By design, any finite input will eventually reach the "done" state or return token_type::parse_error. In each intermediate state, 1 byte of the input is appended to the token_buffer vector, and only the already initialized variables token_buffer, number_type, and error_message are manipulated.
    {
@@ -10280,7 +10277,7 @@ scan_number_zero:
        {
            case '.':
            {
-                add(decimal_point_char);
+                add(current);
                decimal_point_position = token_buffer.size() - 1;
                goto scan_number_decimal1;
            }
@@ -10317,7 +10314,7 @@ scan_number_any1:

            case '.':
            {
-                add(decimal_point_char);
+                add(current);
                decimal_point_position = token_buffer.size() - 1;
                goto scan_number_decimal1;
            }
@@ -10559,9 +10556,9 @@ scan_number_done:

        // Only a number below 1 can carry further insignificant zeros, and only
        // while the count stays at the limit does removing them change the
-        // answer - so this loop is skipped for all but a few tokens. Note
-        // token_buffer holds the locale's decimal point, so the fraction is
-        // located through decimal_point_position rather than by searching '.'.
+        // answer - so this loop is skipped for all but a few tokens. The
+        // fraction is located through decimal_point_position rather than by
+        // searching '.'.
        if (lead_zero != 0)
        {
            JSON_ASSERT(has_dot != 0); // an integer "0" cannot reach the limit
@@ -10579,8 +10576,8 @@ scan_number_done:
    @brief convert the number text in token_buffer to its value and token type

    The digit sequence in token_buffer has already been validated (by the
-    scan_number() state machine or by the contiguous fast path) and holds the
-    locale decimal point in place of '.'. Integers are parsed first and fall
+    scan_number() state machine or by the contiguous fast path) and holds '.'
+    as decimal point, independent of the locale. Integers are parsed first and fall
    back to floating point on overflow. This is shared so both scanners produce
    identical results.

@@ -10660,7 +10657,7 @@ scan_number_done:
        // integer conversion above overflowed. Prefer std::from_chars
        // (Eisel-Lemire, locale-independent, correctly rounded) when available;
        // otherwise the exact Clinger fast path (double only); otherwise the
-        // locale-aware strtof/strtod.
+        // locale-aware strtof/strtod/strtold.
        if (parse_float_from_chars(num_begin, num_end, value_float))
        {
            return token_type::value_float;
@@ -10669,26 +10666,75 @@ scan_number_done:
        // extra pass over the token's bytes, which otherwise shows up on
        // high-precision inputs such as canada.json
        if (mantissa_fits_clinger(mantissa_end)
-                && parse_float_fast(num_begin, num_end, decimal_point_char, value_float))
+                && parse_float_fast(num_begin, num_end, value_float))
        {
            return token_type::value_float;
        }

-        char* endptr = nullptr; // NOLINT(misc-const-correctness,cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-        strtof(value_float, token_buffer.data(), &endptr);
-
-        // we checked the number format before
-        JSON_ASSERT(endptr == token_buffer.data() + token_buffer.size());
-
+        convert_float_locale_aware();
        return token_type::value_float;
    }

+    /*!
+    @brief convert the float in token_buffer with strtof/strtod/strtold
+
+    These functions expect the decimal point of the *current* locale, so it is
+    looked up right before the conversion instead of once when the lexer is
+    constructed: a locale change in between (by a parser callback, a SAX
+    handler, or another thread) must not truncate the value (#5198). The
+    token has been validated before, so if the conversion stops early and the
+    decimal point changed in the meantime, the locale changed between the
+    lookup and the call, and the conversion is repeated with the new decimal
+    point. If the decimal point did not change, a retry cannot succeed: the
+    locale's decimal point is not a single character (e.g., the two-byte
+    U+066B of ar_EG.UTF-8 or fa_IR.UTF-8) and cannot be substituted in place.
+    The value strtod parsed up to that point is kept, as before this change.
+
+    Note that changing the locale in another thread *while* strtod runs is
+    undefined behavior of the C library, which this function cannot prevent.
+    */
+    void convert_float_locale_aware()
+    {
+        const bool has_dot = decimal_point_position != std::string::npos;
+        char decimal_point = get_decimal_point();
+        for (;;)
+        {
+            const bool substitute = has_dot && decimal_point != '.';
+            if (substitute)
+            {
+                token_buffer[decimal_point_position] = static_cast<typename string_t::value_type>(decimal_point);
+            }
+
+            char* endptr = nullptr; // NOLINT(misc-const-correctness,cppcoreguidelines-pro-type-vararg,hicpp-vararg)
+            strtof(value_float, token_buffer.data(), &endptr);
+
+            if (substitute)
+            {
+                // get_string() hands the token to the SAX interface with '.'
+                token_buffer[decimal_point_position] = '.';
+            }
+
+            if (JSON_HEDLEY_LIKELY(endptr == token_buffer.data() + token_buffer.size()))
+            {
+                return;
+            }
+
+            // retry only if the locale changed; otherwise, this would loop forever
+            const char current_decimal_point = get_decimal_point();
+            if (current_decimal_point == decimal_point)
+            {
+                return;
+            }
+            decimal_point = current_decimal_point;
+        }
+    }
+
    /*!
    @brief contiguous fast path for scanning a number

    Parses the whole number token straight from the input buffer, avoiding the
    per-character get()/add() of scan_number(). On success it fills token_buffer
-    (with the locale decimal point substituted, as scan_number() does) and
+    (as scan_number() does) and
    returns the token type. On anything it does not fully recognize as a
    well-formed number it makes no state change and returns
    token_type::uninitialized, so the caller falls back to scan_number(), which
@@ -10804,16 +10850,11 @@ scan_number_done:
        }
 #endif

-        // materialize the token exactly as scan_number() would, substituting the
-        // locale decimal point so convert_number()'s strtof fallback stays valid.
-        // reset() already cleared token_buffer, so append() fills it (assign() is
-        // avoided because custom string_t types need not provide it)
+        // materialize the token exactly as scan_number() would. reset() already
+        // cleared token_buffer, so append() fills it (assign() is avoided
+        // because custom string_t types need not provide it)
        token_buffer.append(reinterpret_cast<const typename string_t::value_type*>(data), len);
-        if (dot_index != std::string::npos)
-        {
-            token_buffer[dot_index] = static_cast<typename string_t::value_type>(decimal_point_char);
-            decimal_point_position = dot_index;
-        }
+        decimal_point_position = dot_index;

        ia.bulk_skip(len - 1);
        position.chars_read_total += (len - 1);
@@ -11080,11 +11121,7 @@ scan_number_done:
    /// return current string value (implicitly resets the token; useful only once)
    string_t& get_string()
    {
-        // translate decimal points from locale back to '.' (#4084)
-        if (decimal_point_char != '.' && decimal_point_position != std::string::npos)
-        {
-            token_buffer[decimal_point_position] = '.';
-        }
+        // a number token holds '.' regardless of the locale (#4084)
        return token_buffer;
    }

@@ -11380,9 +11417,7 @@ scan_number_done:
    number_unsigned_t value_unsigned = 0;
    number_float_t value_float = 0;

-    /// the decimal point
-    const char_int_type decimal_point_char = '.';
-    /// the position of the decimal point in the input
+    /// the position of the decimal point in token_buffer
    std::size_t decimal_point_position = std::string::npos;

    /// whether the caller (e.g. accept()/json_sax_acceptor) only needs the
@@ -14059,6 +14094,80 @@ class binary_reader
        }
    }

+    /*!
+    @brief reads a CBOR object key
+
+    RFC 8949 allows any data item as a map key, but only strings have a
+    counterpart in JSON. A key of any other type is rejected with a message
+    naming that type, rather than the one @ref get_cbor_string gives for a
+    malformed string.
+
+    @param[out] result  created key
+
+    @return whether key creation completed
+    */
+    bool get_cbor_object_key(string_t& result)
+    {
+        // EOF and major type 3 (text string) are left to get_cbor_string
+        if (current == char_traits<char_type>::eof() || (static_cast<unsigned int>(current) & 0xE0u) == 0x60u)
+        {
+            return get_cbor_string(result);
+        }
+
+        const char* found = nullptr;
+        switch (static_cast<unsigned int>(current) >> 5u)
+        {
+            case 0:
+                found = "an unsigned integer";
+                break;
+            case 1:
+                found = "a negative integer";
+                break;
+            case 2:
+                found = "a byte string";
+                break;
+            case 4:
+                found = "an array";
+                break;
+            case 5:
+                found = "a map";
+                break;
+            case 6:
+                found = "a tag";
+                break;
+            default: // major type 7
+                switch (current)
+                {
+                    case 0xF4:
+                    case 0xF5:
+                        found = "a boolean";
+                        break;
+                    case 0xF6:
+                        found = "null";
+                        break;
+                    case 0xF7:
+                        found = "undefined";
+                        break;
+                    case 0xF9:
+                    case 0xFA:
+                    case 0xFB:
+                        found = "a floating-point number";
+                        break;
+                    case 0xFF:
+                        found = "a break stop code";
+                        break;
+                    default:
+                        found = "a simple value";
+                        break;
+                }
+                break;
+        }
+
+        auto last_token = get_token_string();
+        return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read,
+                                exception_message(input_format_t::cbor, concat("only string keys are supported, but found ", found, "; last byte: 0x", last_token), "object key"), nullptr));
+    }
+
    /*!
    @brief reads a definite-length CBOR byte array

@@ -14303,7 +14412,7 @@ class binary_reader
                if (top.is_object)
                {
                    key.clear();
-                    if (JSON_HEDLEY_UNLIKELY(!get_cbor_string(key) || !sax->key(key)))
+                    if (JSON_HEDLEY_UNLIKELY(!get_cbor_object_key(key) || !sax->key(key)))
                    {
                        return false;
                    }
@@ -14804,6 +14913,98 @@ class binary_reader
        }
    }

+    /*!
+    @brief reads a MessagePack object key
+
+    The MessagePack specification allows any type as a map key, but only
+    strings have a counterpart in JSON. A key of any other type is rejected
+    with a message naming that type, rather than the one @ref
+    get_msgpack_string gives for a malformed string.
+
+    @param[out] result  created key
+
+    @return whether key creation completed
+    */
+    bool get_msgpack_object_key(string_t& result)
+    {
+        const char* found = nullptr;
+        switch (current)
+        {
+            case 0xC0:
+                found = "nil";
+                break;
+            case 0xC2:
+            case 0xC3:
+                found = "a boolean";
+                break;
+            case 0xCA:
+            case 0xCB:
+                found = "a float";
+                break;
+            case 0xC4:
+            case 0xC5:
+            case 0xC6:
+                found = "a bin";
+                break;
+            case 0xC7:
+            case 0xC8:
+            case 0xC9:
+            case 0xD4:
+            case 0xD5:
+            case 0xD6:
+            case 0xD7:
+            case 0xD8:
+                found = "an ext";
+                break;
+            case 0xCC:
+            case 0xCD:
+            case 0xCE:
+            case 0xCF:
+            case 0xD0:
+            case 0xD1:
+            case 0xD2:
+            case 0xD3:
+                found = "an integer";
+                break;
+            case 0xDC:
+            case 0xDD:
+                found = "an array";
+                break;
+            case 0xDE:
+            case 0xDF:
+                found = "a map";
+                break;
+            default:
+                // fixint, fixmap, and fixarray; strings, EOF, and the unused
+                // byte 0xC1 are left to get_msgpack_string
+                if (current == char_traits<char_type>::eof())
+                {
+                    return get_msgpack_string(result);
+                }
+                if (current <= 0x7F || current >= 0xE0)
+                {
+                    found = "an integer";
+                }
+                else if (current <= 0x8F)
+                {
+                    found = "a map";
+                }
+                else if (current <= 0x9F)
+                {
+                    found = "an array";
+                }
+                else
+                {
+                    return get_msgpack_string(result);
+                }
+                break;
+        }
+
+        auto last_token = get_token_string();
+        return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read,
+                                exception_message(input_format_t::msgpack, concat("only string keys are supported, but found ", found, "; last byte: 0x", last_token), "object key"), nullptr));
+    }
+
    /*!
    @brief reads a MessagePack byte array

@@ -14966,7 +15167,7 @@ class binary_reader
                {
                    get();
                    key.clear();
-                    if (JSON_HEDLEY_UNLIKELY(!get_msgpack_string(key) || !sax->key(key)))
+                    if (JSON_HEDLEY_UNLIKELY(!get_msgpack_object_key(key) || !sax->key(key)))
                    {
                        return false;
                    }
@@ -18921,11 +19122,11 @@ class json_pointer
            JSON_THROW(detail::out_of_range::create(404, detail::concat("unresolved reference token '", s, "'"), nullptr));
        }

-        // only triggered on special platforms (like 32bit), see also
-        // https://github.com/nlohmann/json/pull/2203
+        // the index does not fit into size_type; on 64-bit platforms this is
+        // only SIZE_MAX itself (see #2203 and #5395)
        if (res >= static_cast<unsigned long long>((std::numeric_limits<size_type>::max)()))  // NOLINT(runtime/int)
        {
-            JSON_THROW(detail::out_of_range::create(410, detail::concat("array index ", s, " exceeds size_type"), nullptr));   // LCOV_EXCL_LINE
+            JSON_THROW(detail::out_of_range::create(410, detail::concat("array index ", s, " exceeds size_type"), nullptr));
        }

        return static_cast<size_type>(res);
@@ -20058,12 +20259,14 @@ class output_stream_adapter : public output_adapter_protocol<CharType>
        : stream(s)
    {}

+    // NOLINTNEXTLINE(portability-template-virtual-member-function)
    void write_character(CharType c) override
    {
        stream.put(c);
    }

    JSON_HEDLEY_NON_NULL(2)
+    // NOLINTNEXTLINE(portability-template-virtual-member-function)
    void write_characters(const CharType* s, std::size_t length) override
    {
        stream.write(s, static_cast<std::streamsize>(length));
@@ -90,11 +90,11 @@ target_compile_options(test_main PUBLIC
    # https://github.com/nlohmann/json/pull/3229
    $<$<CXX_COMPILER_ID:Intel>:-diag-disable=2196>

-    $<$<NOT:$<CXX_COMPILER_ID:MSVC>>:-Wno-deprecated;-Wno-float-equal>
    $<$<CXX_COMPILER_ID:GNU>:-Wno-deprecated-declarations>
    $<$<CXX_COMPILER_ID:Intel>:-diag-disable=1786>)
+target_include_directories(test_main SYSTEM PUBLIC
+    thirdparty/doctest)
 target_include_directories(test_main PUBLIC
-    thirdparty/doctest
    thirdparty/fifo_map
    ${PROJECT_BINARY_DIR}/include)
 target_link_libraries(test_main PUBLIC ${NLOHMANN_JSON_TARGET_NAME})
@@ -12,7 +12,6 @@ target_compile_options(abi_compat_common INTERFACE
    # https://github.com/nlohmann/json/pull/3229
    $<$<CXX_COMPILER_ID:Intel>:-diag-disable=2196>

-    $<$<NOT:$<CXX_COMPILER_ID:MSVC>>:-Wno-deprecated;-Wno-float-equal>
    $<$<CXX_COMPILER_ID:GNU>:-Wno-deprecated-declarations>
    $<$<CXX_COMPILER_ID:Intel>:-diag-disable=1786>)
 target_include_directories(abi_compat_common SYSTEM INTERFACE
@@ -1830,10 +1830,51 @@ TEST_CASE("CBOR")
        SECTION("invalid string in map")
        {
            json _;
-            CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xa1, 0xff, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0xFF", json::parse_error&);
+            CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xa1, 0xff, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found a break stop code; last byte: 0xFF", json::parse_error&);
            CHECK(json::from_cbor(std::vector<uint8_t>({0xa1, 0xff, 0x01}), true, false).is_discarded());
        }

+        SECTION("non-string key (see #2766 and #3381)")
+        {
+            // only text strings map to JSON object keys; any other key is
+            // rejected with a message naming its type
+            const std::vector<std::pair<std::vector<std::uint8_t>, std::string>> cases =
+            {
+                {{0xA1, 0x01, 0x01}, "an unsigned integer; last byte: 0x01"},
+                {{0xA1, 0x20, 0x01}, "a negative integer; last byte: 0x20"},
+                {{0xA1, 0x41, 0x61, 0x01}, "a byte string; last byte: 0x41"},
+                {{0xA1, 0x80, 0x01}, "an array; last byte: 0x80"},
+                {{0xA1, 0xA0, 0x01}, "a map; last byte: 0xA0"},
+                {{0xA1, 0xC0, 0x61, 0x61, 0x01}, "a tag; last byte: 0xC0"},
+                {{0xA1, 0xF4, 0x01}, "a boolean; last byte: 0xF4"},
+                {{0xA1, 0xF5, 0x01}, "a boolean; last byte: 0xF5"},
+                {{0xA1, 0xF6, 0x01}, "null; last byte: 0xF6"},
+                {{0xA1, 0xF7, 0x01}, "undefined; last byte: 0xF7"},
+                {{0xA1, 0xF9, 0x3C, 0x00, 0x01}, "a floating-point number; last byte: 0xF9"},
+                {{0xA1, 0xFA, 0x3F, 0x80, 0x00, 0x00, 0x01}, "a floating-point number; last byte: 0xFA"},
+                {{0xA1, 0xFB, 0x3F, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}, "a floating-point number; last byte: 0xFB"},
+                {{0xA1, 0xE0, 0x01}, "a simple value; last byte: 0xE0"},
+                {{0xA1, 0xF8, 0x20, 0x01}, "a simple value; last byte: 0xF8"},
+                // indefinite-length map
+                {{0xBF, 0x01, 0x01, 0xFF}, "an unsigned integer; last byte: 0x01"},
+            };
+
+            for (const auto& c : cases)
+            {
+                CAPTURE(c.first)
+                const std::string expected = "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found " + c.second;
+                json _;
+                CHECK_THROWS_WITH_AS(_ = json::from_cbor(c.first), expected.c_str(), json::parse_error&);
+                CHECK(json::from_cbor(c.first, true, false).is_discarded());
+            }
+
+            // a key of major type 3 with a reserved length is still reported as
+            // a malformed string, and a missing key as the end of input
+            json _;
+            CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xA1})), "[json.exception.parse_error.110] parse error at byte 2: syntax error while parsing CBOR string: unexpected end of input", json::parse_error&);
+            CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xA1, 0x7C, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0x7C", json::parse_error&);
+        }
+
        SECTION("invalid UTF-8 in string (see #5529)")
        {
            // a two-character text string (major type 3) whose bytes are not
@@ -2284,7 +2325,7 @@ TEST_CASE("CBOR indefinite-length strings do not recurse per chunk")
    SECTION("a break marker outside an indefinite-length string is not a string")
    {
        // 0xFF only closes a string that was opened; on its own it is not one
-        CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xA1, 0xFF, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0xFF", json::parse_error&);
+        CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xA1, 0xFF, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found a break stop code; last byte: 0xFF", json::parse_error&);
    }
 }

@@ -666,7 +666,7 @@ TEST_CASE("parse_float_fast declines what it cannot convert exactly")
    // always safe: the caller then falls back to a slower, exact conversion.
    const auto fast = [](const std::string & s, double & out)
    {
-        return nlohmann::detail::parse_float_fast(s.data(), s.data() + s.size(), '.', out);
+        return nlohmann::detail::parse_float_fast(s.data(), s.data() + s.size(), out);
    };
    double out = 0;

@@ -2525,7 +2525,7 @@ TEST_CASE("diagnostic positions: value lifetime, input adapters, and SAX")

        SECTION("move constructor resets the moved-from value to npos")
        {
-            // basic_json(basic_json&&) (json.hpp, around line 1265) copies
+            // basic_json(basic_json&&) (json.hpp, around line 1951) copies
            // other's start_position/end_position into *this and then resets
            // other's to npos (see the cppcheck-suppress[accessForwarded]
            // annotation there, which flags this reset as worth a second
@@ -1622,7 +1622,7 @@ TEST_CASE("value conversion")

 enum class cards {kreuz, pik, herz, karo};

-// NOLINTNEXTLINE(misc-use-internal-linkage,misc-const-correctness,cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) - false positive
+// NOLINTNEXTLINE(misc-use-internal-linkage,misc-const-correctness) - false positive
 NLOHMANN_JSON_SERIALIZE_ENUM(cards,
 {
    {cards::kreuz, "kreuz"},
@@ -1640,7 +1640,7 @@ enum TaskState // NOLINT(cert-int09-c,readability-enum-initial-value,cppcoreguid
    TS_INVALID = -1,
 };

-// NOLINTNEXTLINE(misc-const-correctness,misc-use-internal-linkage,cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) - false positive
+// NOLINTNEXTLINE(misc-const-correctness,misc-use-internal-linkage) - false positive
 NLOHMANN_JSON_SERIALIZE_ENUM(TaskState,
 {
    {TS_INVALID, nullptr},
@@ -1690,7 +1690,7 @@ TEST_CASE("JSON to enum mapping")

 enum class strict_cards {kreuz, pik, herz, karo, andere}; // andere not included in mapping

-// NOLINTNEXTLINE(misc-use-internal-linkage,misc-const-correctness,cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) - false positive
+// NOLINTNEXTLINE(misc-use-internal-linkage,misc-const-correctness) - false positive
 NLOHMANN_JSON_SERIALIZE_ENUM_STRICT(strict_cards,
 {
    {strict_cards::kreuz, "kreuz"},
@@ -1709,7 +1709,7 @@ enum StrictTaskState // NOLINT(cert-int09-c,readability-enum-initial-value,cppco
    STRICT_TS_INVALID = -1,
 };

-// NOLINTNEXTLINE(misc-const-correctness,misc-use-internal-linkage,cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) - false positive
+// NOLINTNEXTLINE(misc-const-correctness,misc-use-internal-linkage) - false positive
 NLOHMANN_JSON_SERIALIZE_ENUM_STRICT(StrictTaskState,
 {
    {STRICT_TS_INVALID, nullptr},
@@ -12,7 +12,12 @@
 #include <nlohmann/json.hpp>
 using nlohmann::json;

+#include <array>
 #include <clocale>
+#include <map>
+#include <string>
+#include <utility>
+#include <vector>

 struct ParserImpl final: public nlohmann::json_sax<json>
 {
@@ -175,3 +180,208 @@ TEST_CASE("locale-dependent test (LC_NUMERIC=de_DE)")
        MESSAGE("locale de_DE is not usable");
    }
 }
+
+namespace
+{
+// records the numbers of a flat array and switches LC_NUMERIC to the given
+// locale once the array opens - after the lexer was constructed, but before
+// any number in the array is lexed
+struct LocaleSwitchingSax final: public nlohmann::json_sax<json>
+{
+    explicit LocaleSwitchingSax(const char* switch_to)
+        : locale_after_open(switch_to)
+    {}
+
+    bool null() override
+    {
+        return true;
+    }
+    bool boolean(bool /*val*/) override
+    {
+        return true;
+    }
+    bool number_integer(json::number_integer_t /*val*/) override
+    {
+        return true;
+    }
+    bool number_unsigned(json::number_unsigned_t /*val*/) override
+    {
+        return true;
+    }
+    bool number_float(json::number_float_t val, const json::string_t& s) override
+    {
+        values.push_back(val);
+        strings.push_back(s);
+        return true;
+    }
+    bool string(json::string_t& /*val*/) override
+    {
+        return true;
+    }
+    bool binary(json::binary_t& /*val*/) override
+    {
+        return true;
+    }
+    bool start_object(std::size_t /*val*/) override
+    {
+        return true;
+    }
+    bool key(json::string_t& /*val*/) override
+    {
+        return true;
+    }
+    bool end_object() override
+    {
+        return true;
+    }
+    bool start_array(std::size_t /*val*/) override
+    {
+        switched = std::setlocale(LC_NUMERIC, locale_after_open.c_str()) != nullptr;
+        return true;
+    }
+    bool end_array() override
+    {
+        return true;
+    }
+    bool parse_error(std::size_t /*val*/, const std::string& /*val*/, const nlohmann::detail::exception& /*val*/) override
+    {
+        return false;
+    }
+
+    std::string locale_after_open;
+    bool switched = false;
+    std::vector<json::number_float_t> values {}; // NOLINT(readability-redundant-member-init)
+    std::vector<json::string_t> strings {}; // NOLINT(readability-redundant-member-init)
+};
+} // namespace
+
+TEST_CASE("locale changes between lexer construction and number conversion (#5198)")
+{
+    // The numbers are chosen so that the conversion also takes the strtod
+    // fallback, which honors the locale that is current at conversion time:
+    // too many significant digits for Clinger's fast path, an underflow that
+    // std::from_chars rejects, and a plain value.
+    const std::vector<std::string> numbers = {"3.14159265358979323846", "1.5e-400", "12.34", "-0.000123456789012345678"};
+    std::string text = "[";
+    for (const auto& n : numbers)
+    {
+        text += (text.size() == 1 ? "" : ",") + n;
+    }
+    text += "]";
+
+    using long_double_json = nlohmann::basic_json<std::map, std::vector, std::string, bool, std::int64_t, std::uint64_t, long double>;
+
+    // reference values, parsed without a locale switch
+    REQUIRE(std::setlocale(LC_NUMERIC, "C") != nullptr);
+    const json expected = json::parse(text);
+    const long_double_json expected_ld = long_double_json::parse(text);
+
+    const std::array<std::pair<const char*, const char*>, 2> transitions =
+    {
+        {
+            {"C", "de_DE"},
+            {"de_DE", "C"}
+        }
+    };
+
+    for (const auto& transition : transitions)
+    {
+        CAPTURE(transition.first);
+        CAPTURE(transition.second);
+
+        if (std::setlocale(LC_NUMERIC, transition.first) == nullptr)
+        {
+            MESSAGE("locale is not usable");
+            continue;
+        }
+
+        // SAX parsing
+        {
+            LocaleSwitchingSax sax(transition.second);
+            CHECK(json::sax_parse(text, &sax));
+            if (sax.switched)
+            {
+                CHECK(sax.values == expected.get<std::vector<json::number_float_t>>());
+                CHECK(sax.strings == numbers);
+            }
+        }
+
+        // DOM parsing with a callback
+        {
+            bool switched = false;
+            const auto cb = [&](int /*depth*/, json::parse_event_t event, json& /*parsed*/) noexcept
+            {
+                if (event == json::parse_event_t::array_start)
+                {
+                    switched = std::setlocale(LC_NUMERIC, transition.second) != nullptr;
+                }
+                return true;
+            };
+            const json j = json::parse(text, cb);
+            if (switched)
+            {
+                CHECK(j == expected);
+            }
+        }
+
+        // a long double goes through std::strtold unless std::from_chars supports it
+        {
+            bool switched = false;
+            const auto cb = [&](int /*depth*/, long_double_json::parse_event_t event, long_double_json& /*parsed*/) noexcept
+            {
+                if (event == long_double_json::parse_event_t::array_start)
+                {
+                    switched = std::setlocale(LC_NUMERIC, transition.second) != nullptr;
+                }
+                return true;
+            };
+            const long_double_json j = long_double_json::parse(text, cb);
+            if (switched)
+            {
+                CHECK(j == expected_ld);
+            }
+        }
+    }
+
+    CHECK(std::setlocale(LC_NUMERIC, "C") != nullptr);
+}
+
+TEST_CASE("locale with a multi-byte decimal point")
+{
+    // Some locales use a decimal point that is not a single character, e.g.
+    // U+066B ARABIC DECIMAL SEPARATOR (two bytes in UTF-8). It cannot be
+    // substituted in place for '.', so the strtod fallback stops early. The
+    // conversion must still terminate rather than retry forever.
+    const std::array<const char*, 6> names = {{"ar_EG.UTF-8", "ar_SA.UTF-8", "fa_IR.UTF-8", "ps_AF.UTF-8", "ar_EG", "fa_IR"}};
+    bool tested = false;
+    for (const char* name : names)
+    {
+        if (std::setlocale(LC_NUMERIC, name) == nullptr)
+        {
+            continue;
+        }
+        const std::string decimal_point = std::localeconv()->decimal_point;
+        if (decimal_point.size() < 2)
+        {
+            continue;
+        }
+        CAPTURE(name);
+        tested = true;
+
+        // too many significant digits for Clinger's fast path, and an underflow
+        // that std::from_chars rejects: both reach the strtod fallback
+        json j;
+        CHECK_NOTHROW(j = json::parse("[3.14159265358979323846, 1.5e-400, -0.000123456789012345678]"));
+        CHECK(j.is_array());
+        CHECK(json::accept("3.14159265358979323846"));
+
+        // a value the locale-independent paths convert is not affected
+        CHECK(json::parse("12.5") == 12.5);
+    }
+    if (!tested)
+    {
+        MESSAGE("no locale with a multi-byte decimal point is usable");
+    }
+
+    CHECK(std::setlocale(LC_NUMERIC, "C") != nullptr);
+}
@@ -1551,10 +1551,69 @@ TEST_CASE("MessagePack")
        SECTION("invalid string in map")
        {
            json _;
-            CHECK_THROWS_WITH_AS(_ = json::from_msgpack(std::vector<uint8_t>({0x81, 0xff, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack string: expected length specification (0xA0-0xBF, 0xD9-0xDB); last byte: 0xFF", json::parse_error&);
+            CHECK_THROWS_WITH_AS(_ = json::from_msgpack(std::vector<uint8_t>({0x81, 0xff, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack object key: only string keys are supported, but found an integer; last byte: 0xFF", json::parse_error&);
            CHECK(json::from_msgpack(std::vector<uint8_t>({0x81, 0xff, 0x01}), true, false).is_discarded());
        }

+        SECTION("non-string key (see #3381)")
+        {
+            // only strings map to JSON object keys; any other key is rejected
+            // with a message naming its type
+            const std::vector<std::pair<std::vector<std::uint8_t>, std::string>> cases =
+            {
+                {{0x81, 0xC0, 0x01}, "nil; last byte: 0xC0"},
+                {{0x81, 0xC2, 0x01}, "a boolean; last byte: 0xC2"},
+                {{0x81, 0xC3, 0x01}, "a boolean; last byte: 0xC3"},
+                {{0x81, 0xCA, 0x3F, 0x80, 0x00, 0x00, 0x01}, "a float; last byte: 0xCA"},
+                {{0x81, 0xCB, 0x3F, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}, "a float; last byte: 0xCB"},
+                {{0x81, 0xC4, 0x00, 0x01}, "a bin; last byte: 0xC4"},
+                {{0x81, 0xC5, 0x00, 0x00, 0x01}, "a bin; last byte: 0xC5"},
+                {{0x81, 0xC6, 0x00, 0x00, 0x00, 0x00, 0x01}, "a bin; last byte: 0xC6"},
+                {{0x81, 0xC7, 0x00, 0x01, 0x01}, "an ext; last byte: 0xC7"},
+                {{0x81, 0xC8, 0x00, 0x00, 0x01, 0x01}, "an ext; last byte: 0xC8"},
+                {{0x81, 0xC9, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01}, "an ext; last byte: 0xC9"},
+                {{0x81, 0xD4, 0x01, 0x00, 0x01}, "an ext; last byte: 0xD4"},
+                {{0x81, 0xD5, 0x01, 0x00, 0x00, 0x01}, "an ext; last byte: 0xD5"},
+                {{0x81, 0xD6, 0x01, 0x00, 0x00, 0x00, 0x00, 0x01}, "an ext; last byte: 0xD6"},
+                {{0x81, 0xD7, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}, "an ext; last byte: 0xD7"},
+                {{0x81, 0xD8, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}, "an ext; last byte: 0xD8"},
+                {{0x81, 0xCC, 0x01, 0x01}, "an integer; last byte: 0xCC"},
+                {{0x81, 0xCD, 0x00, 0x01, 0x01}, "an integer; last byte: 0xCD"},
+                {{0x81, 0xCE, 0x00, 0x00, 0x00, 0x01, 0x01}, "an integer; last byte: 0xCE"},
+                {{0x81, 0xCF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01}, "an integer; last byte: 0xCF"},
+                {{0x81, 0xD0, 0x01, 0x01}, "an integer; last byte: 0xD0"},
+                {{0x81, 0xD1, 0x00, 0x01, 0x01}, "an integer; last byte: 0xD1"},
+                {{0x81, 0xD2, 0x00, 0x00, 0x00, 0x01, 0x01}, "an integer; last byte: 0xD2"},
+                {{0x81, 0xD3, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01}, "an integer; last byte: 0xD3"},
+                {{0x81, 0x00, 0x01}, "an integer; last byte: 0x00"},
+                {{0x81, 0x7F, 0x01}, "an integer; last byte: 0x7F"},
+                {{0x81, 0xE0, 0x01}, "an integer; last byte: 0xE0"},
+                {{0x81, 0x80, 0x01}, "a map; last byte: 0x80"},
+                {{0x81, 0x8F, 0x01}, "a map; last byte: 0x8F"},
+                {{0x81, 0xDE, 0x00, 0x00, 0x01}, "a map; last byte: 0xDE"},
+                {{0x81, 0xDF, 0x00, 0x00, 0x00, 0x00, 0x01}, "a map; last byte: 0xDF"},
+                {{0x81, 0x90, 0x01}, "an array; last byte: 0x90"},
+                {{0x81, 0x9F, 0x01}, "an array; last byte: 0x9F"},
+                {{0x81, 0xDC, 0x00, 0x00, 0x01}, "an array; last byte: 0xDC"},
+                {{0x81, 0xDD, 0x00, 0x00, 0x00, 0x00, 0x01}, "an array; last byte: 0xDD"},
+            };
+
+            for (const auto& c : cases)
+            {
+                CAPTURE(c.first)
+                const std::string expected = "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack object key: only string keys are supported, but found " + c.second;
+                json _;
+                CHECK_THROWS_WITH_AS(_ = json::from_msgpack(c.first), expected.c_str(), json::parse_error&);
+                CHECK(json::from_msgpack(c.first, true, false).is_discarded());
+            }
+
+            json _;
+            // the unused byte 0xC1 is still reported as a malformed string
+            CHECK_THROWS_WITH_AS(_ = json::from_msgpack(std::vector<uint8_t>({0x81, 0xC1, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack string: expected length specification (0xA0-0xBF, 0xD9-0xDB); last byte: 0xC1", json::parse_error&);
+            // a missing key is still reported as the end of input
+            CHECK_THROWS_WITH_AS(_ = json::from_msgpack(std::vector<uint8_t>({0x81})), "[json.exception.parse_error.110] parse error at byte 2: syntax error while parsing MessagePack string: unexpected end of input", json::parse_error&);
+        }
+
        SECTION("invalid UTF-8 in string (see #5529)")
        {
            // a fixstr of length 2 (0xA0 | 2) whose bytes are not valid UTF-8
@@ -1018,7 +1018,7 @@ TEST_CASE("regression tests 1")
        };

        json _;
-        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0x98", json::parse_error&);
+        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found an array; last byte: 0x98", json::parse_error&);

        // related test case: nonempty UTF-8 string (indefinite length)
        std::vector<uint8_t> const vec1 {0x7f, 0x61, 0x61};
@@ -1065,7 +1065,7 @@ TEST_CASE("regression tests 1")
        };

        json _;
-        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec1), "[json.exception.parse_error.113] parse error at byte 13: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0xB4", json::parse_error&);
+        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec1), "[json.exception.parse_error.113] parse error at byte 13: syntax error while parsing CBOR object key: only string keys are supported, but found a map; last byte: 0xB4", json::parse_error&);

        // related test case: double-precision
        std::vector<uint8_t> const vec2
@@ -1077,7 +1077,7 @@ TEST_CASE("regression tests 1")
            0x96, 0x96, 0xb4, 0xb4, 0xfa, 0x94, 0x94, 0x61,
            0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0xfb
        };
-        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec2), "[json.exception.parse_error.113] parse error at byte 13: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0xB4", json::parse_error&);
+        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec2), "[json.exception.parse_error.113] parse error at byte 13: syntax error while parsing CBOR object key: only string keys are supported, but found a map; last byte: 0xB4", json::parse_error&);
    }

    SECTION("issue #452 - Heap-buffer-overflow (OSS-Fuzz issue 585)")
@@ -112,7 +112,7 @@ enum class for_1647
    two
 };

-// NOLINTNEXTLINE(misc-const-correctness,cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays): this is a false positive
+// NOLINTNEXTLINE(misc-const-correctness): this is a false positive
 NLOHMANN_JSON_SERIALIZE_ENUM(for_1647,
 {
    {for_1647::one, "one"},
Author	SHA1	Message	Date
Niels Lohmann	b640bf728d	Re-enable portability-template-virtual-member-function; remove redundant forwards .clang-tidy disabled three checks "to get the CI going" (#4489, 2024-11-13): portability-template-virtual-member-function, bugprone-use-after-move and its alias hicpp-invalid-access-moved. portability-template-virtual-member-function only flagged output_stream_adapter::write_character/write_characters; annotate both with NOLINT and re-enable the check. bugprone-use-after-move flagged several double forwards that have no effect at runtime: - from_json.hpp calls std::forward<BasicJsonType>(j).at(Idx) inside pack expansions; at() has no ref-qualified overloads and always returns an lvalue reference, so the forward is a no-op. Replace with plain j.at(Idx) in all four places. - the move constructor forwards the whole object to its base class and then reads other's members. That is item 9 of #5724 (together with its cppcheck suppressions) and is left to that change. - input_adapters.hpp forwards the container twice on purpose, so the begin/end iterator types match adapter_type; annotate with NOLINT and a comment instead of changing behavior. The check still flags the move constructor (see above) and two sites in at(KeyType&&) (both overloads, json.hpp, in the throw's string_t(std::forward<KeyType>(key)) after find(std::forward<KeyType>(key))). Open PR #5689 rewrites that hunk, so bugprone-use-after-move (and hicpp-invalid-access-moved) stay disabled for now, with a comment explaining why; re-enable them once #5689 and the #5724 move-constructor change have landed. Also resolve the portability-avoid-pragma-once TODO: single_include never has #pragma once (amalgamate.py strips it) and every supported compiler accepts it in include/, so keep it disabled with an explanatory comment instead of a TODO. Fix the stale "json.hpp, around line 1265" comment in unit-class_parser.cpp, which now points at the move constructor's actual line. Behavior, the public API and the ABI do not change. Verified with clang-tidy 22.1.8 that portability-template-virtual-member-function now reports nothing, that bugprone-use-after-move/ hicpp-invalid-access-moved report only the known at(KeyType&&) and move-constructor sites, and that unit-custom-base-class, unit-constructor1, unit-conversions, unit-element_access2, unit-class_parser and unit-diagnostic-positions (JSON_DIAGNOSTIC_POSITIONS=1) compile under ASan/UBSan and pass with the same assertion counts as before. Ran make amalgamate. Part of #5725 Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-09-30 10:33:04 +02:00
Niels Lohmann	27db8bd678	Remove the no-op ci_clang_analyze target ci_clang_analyze configured the build with the real compiler and only then wrapped ninja with scan-build. scan-build intercepts compiles by overriding CC/CXX, but build.ninja already had the compiler path baked in from the configure step, so every run bypassed the analyzer: CI logs show "No bugs found" after a normal build, never an analysis. The job also used Debian's frozen clang-tools-14 rather than the image's own clang, and CLANG_ANALYZER_CHECKS still named three valist.* checkers that current clang merged into security.VAList. ci_clang_tidy already runs every clang-analyzer-* check (via .clang-tidy's "Checks: '*'") with warnings as errors, so nothing is lost by removing the dead job. Delete ci_clang_analyze, CLANG_ANALYZER_CHECKS and the SCAN_BUILD_TOOL lookup from cmake/ci.cmake, drop it from the ubuntu.yml ci_static_analysis_clang matrix, and drop the now-unused clang-tools apt package (iwyu stays for ci_single_binaries). Reword quality_assurance.md and assurance_case.md, which described the dead job as a working control, to say the Clang Static Analyzer checks run through clang-tidy. Verified that `cmake -DJSON_CI=ON` still configures cleanly and that ci_clang_analyze no longer appears in the generated build or in any CMake/workflow file. Part of #5725 Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-09-30 09:55:24 +02:00
Niels Lohmann	819838839d	Include doctest as a SYSTEM directory instead of disabling warnings for all tests test_main added -Wno-deprecated and -Wno-float-equal as PUBLIC compile options for every non-MSVC compiler, so they were applied to every translation unit, library headers included, and silenced the CI warnings meant to check the library's own -Wfloat-equal pragmas. The only code that actually needed the suppression was the vendored doctest.h, which was included as a normal (non-SYSTEM) directory. Include thirdparty/doctest as SYSTEM for test_main, matching what tests/abi/CMakeLists.txt already does, and drop the two suppressions from both targets. Verified locally that unit-comparison, unit-conversions and unit-constructor1 compile clean with -Werror -Weverything and doctest as -isystem, and that CMake still configures with JSON_BuildTests=ON. Part of #5725 Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-09-30 09:54:07 +02:00
Niels Lohmann	20bbb137ba	Name all three C-array check aliases in the enum-macro NOLINTs NLOHMANN_JSON_SERIALIZE_ENUM(_STRICT) suppressed the c-array warning under modernize-avoid-c-arrays only, but clang-tidy emits the same diagnostic under the aliases cppcoreguidelines-avoid-c-arrays and hicpp-avoid-c-arrays too. Any user running those checks got a false positive at every macro expansion, and our own tests needed a local NOLINT at each call site to work around it. Name all three aliases in the four macro comments instead, and drop the now-redundant c-array names from the five test call-site NOLINTs. Comment-only change; behavior, the public API, and the ABI do not change. Ran make amalgamate. Part of #5725 Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-09-30 09:52:09 +02:00
Niels Lohmann	146b9e7615	Drop stale LCOV_EXCL_LINE from the json_pointer out_of_range.410 throw The comment said the size_type overflow check in array_index() is only triggered on special platforms like 32-bit, and the throw was excluded from coverage. On 64-bit platforms the check is true for SIZE_MAX itself, and unit-json_pointer.cpp has asserted that case four times since #5395, so the line is executed in the coverage job. Reword the comment and remove the exclusion marker so the coverage report notices if the tests stop reaching it. Part of #5725 Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-09-30 09:44:28 +02:00
Niels Lohmann	633de8e44b	Fix CI: clang-tidy and GCC -Wnoexcept in the locale test (#5613 ) #5597 was merged before all of its CI jobs had run, and two of them fail on develop now, and so on every pull request: - ci_clang_tidy: cert-err33-c for the two std::setlocale(LC_NUMERIC, "C") calls whose result was discarded. Check the result, like the other resets in the file. - ci_test_standards_gcc (20) with GCC 16: -Wnoexcept for the two parser callbacks, which cannot throw but were not declared noexcept. Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-09-28 22:20:43 +02:00
Niels Lohmann	fc03b9912e	Look up the locale decimal point at conversion time, not lexer construction (#5597 ) * Look up the locale decimal point at conversion time, not lexer construction The lexer read localeconv()->decimal_point once in its constructor and wrote that character into token_buffer in place of '.'. The strtod fallback then used the locale current at conversion time, so an LC_NUMERIC change in between (parser callback, SAX handler, another thread) truncated the value in release builds and fired the endptr assertion in debug builds. token_buffer now always holds '.'. Only the strtof/strtod/strtold fallback depends on the locale: it looks up the decimal point right before the call, restores '.' afterwards, and repeats the conversion if the locale changed in between. As a side effect, std::from_chars and Clinger's fast path now also apply under locales whose decimal point is not '.'. Fixes #5198 Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Stop the strtod retry loop when the decimal point is unchanged convert_float_locale_aware() repeated the conversion until strtod consumed the whole token, assuming an early stop can only mean a locale change. Under a locale whose decimal point is not a single character (e.g. the two-byte U+066B of ar_EG.UTF-8, ar_SA.UTF-8, or fa_IR.UTF-8, all available on macOS), the in-place substitution can never succeed, so parsing any float that reaches the strtod fallback (for example 3.14159265358979323846 at C++11) hung forever. Before this branch, the same input was truncated. Retry only if the decimal point changed since the previous attempt; otherwise keep the value strtod parsed so far, as before. Add a test that parses such numbers under a multi-byte decimal point locale; it hangs without this change. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix -Weffc++ errors in the #5198 locale test GCC's -Weffc++ (an error in ci_test_gcc and ci_test_standards_gcc) rejected LocaleSwitchingSax: it has a pointer data member but does not declare its copy operations, and its vectors are not initialized in the member initializer list. Store the locale name as a std::string and give the vectors brace initializers, like SaxEventLogger in unit-deserialization.cpp. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-09-28 17:56:11 +02:00
Niels Lohmann	9e1a09eec0	Name the key type when rejecting non-string CBOR/MessagePack map keys (#5594 ) * Name the key type when rejecting non-string CBOR/MessagePack map keys CBOR and MessagePack allow map keys of any type, but JSON object keys are always strings, so such maps are rejected. The error so far was the one for a malformed string (e.g. "expected length specification (0xA0-0xBF, 0xD9-0xDB); last byte: 0xC0" for a nil key), which does not tell the user what went wrong. Report the type of the key instead: syntax error while parsing MessagePack object key: only string keys are supported, but found nil; last byte: 0xC0 The exception id (parse_error.113) and type are unchanged. Malformed string keys and a missing key keep their previous messages. Document the restriction on the CBOR and MessagePack pages. Refs #2766, #3381 Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Point the MessagePack key note to the spec's profile section The note linked to "Serialization: type to format conversion", which says nothing about key types. Restricting map keys to strings is only mentioned in the "Profile" section (under "Future discussion") as an example of a JSON-compatible profile, so link there and describe it as such instead of as a permission. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-09-28 17:51:07 +02:00