Route hand-rolled diagnostic pragmas through Hedley

Several places in the library hand-roll compiler diagnostic suppression with raw `#pragma`/`#ifdef __GNUC__`/`#ifdef __clang__` guards instead of using the Hedley primitives already bundled and used elsewhere (JSON_HEDLEY_DIAGNOSTIC_PUSH/POP, JSON_HEDLEY_PRAGMA, ...). Converted six of the seven listed push/pop pairs to use those primitives instead of raw `#pragma GCC diagnostic`/`#pragma clang diagnostic` text: - include/nlohmann/json.hpp (~3770, ~3863): -Wfloat-equal - include/nlohmann/detail/conversions/to_chars.hpp (~1078): -Wfloat-equal - include/nlohmann/detail/output/binary_writer.hpp (~1844): -Wfloat-equal - include/nlohmann/detail/iterators/iteration_proxy.hpp (~211): -Wmismatched-tags - include/nlohmann/detail/exceptions.hpp (~36): -Wweak-vtables iteration_proxy.hpp did not previously include macro_scope.hpp itself (it only compiled because some other header included earlier in json.hpp happened to pull macro_scope.hpp in first); it now includes it directly like the other detail headers that use Hedley macros, so it is self-contained. Each push/pop pair now uses JSON_HEDLEY_DIAGNOSTIC_PUSH/POP unconditionally (a no-op on compilers that don't need it) and wraps the actual `#pragma ... diagnostic ignored` text in JSON_HEDLEY_PRAGMA so it goes through Hedley's _Pragma()-based emission instead of a raw #pragma line, while keeping the original `#ifdef __GNUC__` / `#if defined(__clang__)` guard around the ignored-pragma itself. Deviation from the issue's suggested transformation: the issue's example replaces the `#ifdef __GNUC__` guard with `#if JSON_HEDLEY_HAS_WARNING("-Wfloat-equal")`. JSON_HEDLEY_HAS_WARNING is implemented purely via Clang's `__has_warning` builtin and evaluates to 0 on real GCC (`#define JSON_HEDLEY_HAS_WARNING(warning) (0)` when `__has_warning` is not defined), so adopting it verbatim would silently stop suppressing -Wfloat-equal on GCC -- a real regression, not just a style change. The existing `#ifdef __GNUC__` / `#if defined(__clang__)` guards were kept for the ignored-pragma to stay behavior-preserving, and only the push/pop/pragma-emission mechanism was routed through Hedley. Two of the seven locations from the issue (the -Wignored-attributes push at the very top of json.hpp and its matching pop after `#include <nlohmann/detail/macro_unscope.hpp>`) were intentionally left unconverted: - The push, at the very top of json.hpp, runs before `detail/macro_scope.hpp` (and therefore hedley.hpp) has been included anywhere in the translation unit, so JSON_HEDLEY_DIAGNOSTIC_PUSH is not yet defined at that point. - The pop runs after `macro_unscope.hpp`, which -- via hedley_undef.hpp -- has already #undef'd every JSON_HEDLEY_* macro (by design, see #5408) precisely so they don't leak to users, so JSON_HEDLEY_DIAGNOSTIC_POP is no longer defined by the time the pop is reached either. Making this one pair work would require either hoisting the ~2000 line vendored hedley.hpp to the very top of the amalgamated single header (a much bigger structural change to single_include than a pure mechanism swap) or special-casing this one pop ahead of the general macro cleanup. Both are riskier than the mechanical, behavior-preserving change requested, so this pair was left as-is. ## Validation - Compiled include/nlohmann/json.hpp and single_include/nlohmann/json.hpp with `-Wall -Wextra -Wfloat-equal -Wmismatched-tags -Wweak-vtables` (clang, which self-identifies as __GNUC__ too): no warnings, same as before the change. - Compiled and ran tests/src/unit-to_chars.cpp, unit-conversions.cpp, unit-iterators1.cpp, unit-iterators2.cpp, and unit-class_parser.cpp against the fixed include/: all pass. - Compiled unit-msgpack.cpp, unit-bjdata.cpp, and unit-ubjson.cpp (which exercise binary_writer.hpp's write_compact_float extensively): all compile cleanly; the vast majority of assertions pass (the only failures are pre-existing environment issues unrelated to this change -- missing generated test-data files, not code correctness). - Ran `make amalgamate`; the single_include diff is limited to exactly the lines touched in include/, with no unrelated reordering. - No real (non-Apple) GCC was available in this environment to test directly; the `_Pragma("GCC diagnostic ...")` text emitted by JSON_HEDLEY_PRAGMA is byte-identical to the prior `#pragma GCC diagnostic ...` text, and the `#ifdef __GNUC__` guard is unchanged, so GCC's behavior is expected to be identical. CI covers the GCC matrix. This PR is stacked on top of #5475 (issue-5408-hedley-undef-leak) since both touch the same files; only the last commit here is new. Fixes #5409. Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-09-06 00:08:00 +00:00 · 2026-09-05 21:01:30 +02:00
10 changed files with 505 additions and 247 deletions
@@ -1,4 +1,4 @@
-.PHONY: pretty clean ChangeLog.md release update_hedley update_hedley_undef
+.PHONY: pretty clean ChangeLog.md release

 ##########################################################################
 # configuration
@@ -41,8 +41,6 @@ all:
 	@echo "fuzz_testing_ubjson - prepare fuzz testing of the UBJSON parser"
 	@echo "pretty - beautify code with Artistic Style"
 	@echo "run_benchmarks - build and run benchmarks"
-	@echo "update_hedley - download Hedley and regenerate hedley.hpp / hedley_undef.hpp"
-	@echo "update_hedley_undef - rebuild hedley_undef.hpp from the JSON_HEDLEY_* #define names in hedley.hpp"


 ##########################################################################
@@ -243,24 +241,11 @@ update_hedley:
 	rm -f include/nlohmann/thirdparty/hedley/hedley.hpp include/nlohmann/thirdparty/hedley/hedley_undef.hpp
 	curl https://raw.githubusercontent.com/nemequ/hedley/master/hedley.h -o include/nlohmann/thirdparty/hedley/hedley.hpp
 	$(SED) -i 's/HEDLEY_/JSON_HEDLEY_/g' include/nlohmann/thirdparty/hedley/hedley.hpp
+	grep -oE "#[[:blank:]]*define[[:blank:]]+JSON_HEDLEY_[A-Za-z0-9_]+" include/nlohmann/thirdparty/hedley/hedley.hpp | awk '{print $$NF}' | grep -v "__" | sort -u | $(SED) 's/^/#undef /' > include/nlohmann/thirdparty/hedley/hedley_undef.hpp
 	$(SED) -i '1s/^/#pragma once\n\n/' include/nlohmann/thirdparty/hedley/hedley.hpp
-	$(MAKE) update_hedley_undef
+	$(SED) -i '1s/^/#pragma once\n\n/' include/nlohmann/thirdparty/hedley/hedley_undef.hpp
 	$(MAKE) amalgamate

-# Rebuild hedley_undef.hpp from every JSON_HEDLEY_* name that hedley.hpp
-# #defines. Hedley does not #undef all of its public macros internally (see
-# #5408), so grepping those #undef lines misses names such as
-# JSON_HEDLEY_PRAGMA. cmake/scripts/gen_hedley_undef_check.cmake is the
-# single source of truth for this extraction (tests/CMakeLists.txt uses the
-# same script, in MODE=checks, to generate the matching leak-check test), so
-# the vendored header, the generated #undef list, and the regression test
-# cannot drift apart.
-update_hedley_undef:
-	cmake -DHEDLEY_HPP=include/nlohmann/thirdparty/hedley/hedley.hpp \
-	      -DOUTPUT=include/nlohmann/thirdparty/hedley/hedley_undef.hpp \
-	      -DMODE=undef \
-	      -P cmake/scripts/gen_hedley_undef_check.cmake
-
 ##########################################################################
 # serve_header.py
 ##########################################################################
@@ -1,105 +0,0 @@
-# Shared extractor for the JSON_HEDLEY_* macro names defined in hedley.hpp.
-#
-# Every macro that hedley.hpp #defines must be #undef-ed again once json.hpp
-# has been fully processed (see include/nlohmann/detail/macro_unscope.hpp
-# and https://github.com/nlohmann/json/issues/5408). Deriving the macro list
-# straight from hedley.hpp here -- instead of hand-maintaining it in two
-# places -- means hedley_undef.hpp and the regression test that checks for
-# leaked macros can never drift apart, even after a future `make
-# update_hedley` pulls in new macros from upstream Hedley.
-#
-#   MODE=undef  (default): write hedley_undef.hpp (SPDX header, #pragma once,
-#               one #undef per macro name) -- used by `make update_hedley_undef`
-#   MODE=checks:            write one #ifdef/FAIL_CHECK/#endif per macro name,
-#               meant to be #include-d inside a TEST_CASE -- used by
-#               tests/CMakeLists.txt to (re)generate the include for
-#               tests/src/unit-no-macro-leak.cpp
-#
-# Required variables:
-#   HEDLEY_HPP  path to include/nlohmann/thirdparty/hedley/hedley.hpp
-#   OUTPUT      path of the file to (over)write
-# Optional:
-#   MODE        "undef" (default) or "checks"
-
-if(NOT DEFINED HEDLEY_HPP OR NOT DEFINED OUTPUT)
-    message(FATAL_ERROR "HEDLEY_HPP and OUTPUT must be set")
-endif()
-
-if(NOT EXISTS "${HEDLEY_HPP}")
-    message(FATAL_ERROR "Hedley header not found: ${HEDLEY_HPP}")
-endif()
-
-if(NOT DEFINED MODE)
-    set(MODE undef)
-endif()
-
-if(NOT MODE STREQUAL "undef" AND NOT MODE STREQUAL "checks")
-    message(FATAL_ERROR "MODE must be undef or checks, got: ${MODE}")
-endif()
-
-# Line-anchored, like `grep -oE "^[[:blank:]]*#[[:blank:]]*define[[:blank:]]+JSON_HEDLEY_[A-Za-z0-9_]+"`.
-# Unanchored matching would also pick up JSON_HEDLEY_* mentions inside
-# comments or string literals elsewhere in the file, which must not turn
-# into #undef lines.
-file(STRINGS "${HEDLEY_HPP}" hedley_lines)
-set(macro_names)
-foreach(line IN LISTS hedley_lines)
-    if("${line}" MATCHES "^[ \t]*#[ \t]*define[ \t]+(JSON_HEDLEY_[A-Za-z0-9_]+)")
-        list(APPEND macro_names "${CMAKE_MATCH_1}")
-    endif()
-endforeach()
-
-if(NOT macro_names)
-    message(FATAL_ERROR "No JSON_HEDLEY_* macros found in ${HEDLEY_HPP}")
-endif()
-
-list(REMOVE_DUPLICATES macro_names)
-# Lexicographic, locale-independent (ASCII-only names) -- matches `LC_ALL=C sort`.
-list(SORT macro_names COMPARE STRING)
-list(LENGTH macro_names macro_count)
-
-set(generated "")
-if(MODE STREQUAL "undef")
-    # Same banner `make update_hedley_undef` would stamp by hand, so the
-    # recipe is self-contained and its output is byte-stable across reruns.
-    string(APPEND generated "//     __ _____ _____ _____\n")
-    string(APPEND generated "//  __|  |   __|     |   | |  JSON for Modern C++\n")
-    string(APPEND generated "// |  |  |__   |  |  | | | |  version 3.12.0\n")
-    string(APPEND generated "// |_____|_____|_____|_|___|  https://github.com/nlohmann/json\n")
-    string(APPEND generated "//\n")
-    string(APPEND generated "// SPDX-FileCopyrightText: 2013-2026 Niels Lohmann <https://nlohmann.me>\n")
-    string(APPEND generated "// SPDX-License-Identifier: MIT\n")
-    string(APPEND generated "\n")
-    string(APPEND generated "#pragma once\n")
-    string(APPEND generated "\n")
-    foreach(name IN LISTS macro_names)
-        string(APPEND generated "#undef ${name}\n")
-    endforeach()
-else()
-    string(APPEND generated "// This file is generated by cmake/scripts/gen_hedley_undef_check.cmake\n")
-    string(APPEND generated "// from include/nlohmann/thirdparty/hedley/hedley.hpp. Do not edit it by\n")
-    string(APPEND generated "// hand -- it is regenerated on every build. ${macro_count} macros checked.\n\n")
-    foreach(name IN LISTS macro_names)
-        string(APPEND generated "#ifdef ${name}\n")
-        string(APPEND generated "    FAIL_CHECK(\"${name} leaked after including nlohmann/json.hpp\");\n")
-        string(APPEND generated "#endif\n")
-    endforeach()
-endif()
-
-get_filename_component(output_dir "${OUTPUT}" DIRECTORY)
-if(output_dir)
-    file(MAKE_DIRECTORY "${output_dir}")
-endif()
-
-# Avoid rewriting the file (and busting downstream incremental rebuilds)
-# when the content has not actually changed.
-set(write_output TRUE)
-if(EXISTS "${OUTPUT}")
-    file(READ "${OUTPUT}" existing_content)
-    if(existing_content STREQUAL generated)
-        set(write_output FALSE)
-    endif()
-endif()
-if(write_output)
-    file(WRITE "${OUTPUT}" "${generated}")
-endif()
@@ -1074,9 +1074,9 @@ char* to_chars(char* first, const char* last, FloatType value)
        *first++ = '-';
    }

+    JSON_HEDLEY_DIAGNOSTIC_PUSH
 #ifdef __GNUC__
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wfloat-equal"
+    JSON_HEDLEY_PRAGMA(GCC diagnostic ignored "-Wfloat-equal")
 #endif
    if (value == 0) // +-0
    {
@@ -1086,9 +1086,7 @@ char* to_chars(char* first, const char* last, FloatType value)
        *first++ = '0';
        return first;
    }
-#ifdef __GNUC__
-#pragma GCC diagnostic pop
-#endif
+    JSON_HEDLEY_DIAGNOSTIC_POP

    JSON_ASSERT(last - first >= std::numeric_limits<FloatType>::max_digits10);

@@ -32,9 +32,9 @@
 // functions to. As a result, we suppress this warning here to avoid client
 // code stumbling over this. See https://github.com/nlohmann/json/issues/4087
 // for a discussion.
+JSON_HEDLEY_DIAGNOSTIC_PUSH
 #if defined(__clang__)
-    #pragma clang diagnostic push
-    #pragma clang diagnostic ignored "-Wweak-vtables"
+    JSON_HEDLEY_PRAGMA(clang diagnostic ignored "-Wweak-vtables")
 #endif

 NLOHMANN_JSON_NAMESPACE_BEGIN
@@ -286,6 +286,4 @@ class other_error : public exception
 }  // namespace detail
 NLOHMANN_JSON_NAMESPACE_END

-#if defined(__clang__)
-    #pragma clang diagnostic pop
-#endif
+JSON_HEDLEY_DIAGNOSTIC_POP
@@ -18,6 +18,7 @@
 #endif

 #include <nlohmann/detail/abi_macros.hpp>
+#include <nlohmann/detail/macro_scope.hpp>
 #include <nlohmann/detail/meta/type_traits.hpp>
 #include <nlohmann/detail/string_utils.hpp>
 #include <nlohmann/detail/value_t.hpp>
@@ -206,10 +207,10 @@ NLOHMANN_JSON_NAMESPACE_END
 namespace std
 {

+// Fix: https://github.com/nlohmann/json/issues/1401
+JSON_HEDLEY_DIAGNOSTIC_PUSH
 #if defined(__clang__)
-    // Fix: https://github.com/nlohmann/json/issues/1401
-    #pragma clang diagnostic push
-    #pragma clang diagnostic ignored "-Wmismatched-tags"
+    JSON_HEDLEY_PRAGMA(clang diagnostic ignored "-Wmismatched-tags")
 #endif
 template<typename IteratorType>
 class tuple_size<::nlohmann::detail::iteration_proxy_value<IteratorType>> // NOLINT(cert-dcl58-cpp)
@@ -223,9 +224,7 @@ class tuple_element<N, ::nlohmann::detail::iteration_proxy_value<IteratorType >>
                     get<N>(std::declval <
                            ::nlohmann::detail::iteration_proxy_value<IteratorType >> ()));
 };
-#if defined(__clang__)
-    #pragma clang diagnostic pop
-#endif
+JSON_HEDLEY_DIAGNOSTIC_POP

 }  // namespace std

@@ -1849,9 +1849,9 @@ class binary_writer

    void write_compact_float(const number_float_t n, detail::input_format_t format)
    {
+        JSON_HEDLEY_DIAGNOSTIC_PUSH
 #ifdef __GNUC__
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wfloat-equal"
+        JSON_HEDLEY_PRAGMA(GCC diagnostic ignored "-Wfloat-equal")
 #endif
        if (!std::isfinite(n) || ((static_cast<double>(n) >= static_cast<double>(std::numeric_limits<float>::lowest()) &&
                                   static_cast<double>(n) <= static_cast<double>((std::numeric_limits<float>::max)()) &&
@@ -1869,9 +1869,7 @@ class binary_writer
                                : get_msgpack_float_prefix(n));
            write_number(n);
        }
-#ifdef __GNUC__
-#pragma GCC diagnostic pop
-#endif
+        JSON_HEDLEY_DIAGNOSTIC_POP
    }

  public:
@@ -3769,15 +3769,13 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
    /// @sa https://json.nlohmann.me/api/basic_json/operator_eq/
    bool operator==(const_reference rhs) const noexcept
    {
+        JSON_HEDLEY_DIAGNOSTIC_PUSH
 #ifdef __GNUC__
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wfloat-equal"
+        JSON_HEDLEY_PRAGMA(GCC diagnostic ignored "-Wfloat-equal")
 #endif
        const_reference lhs = *this;
        JSON_IMPLEMENT_OPERATOR( ==, true, false, false)
-#ifdef __GNUC__
-#pragma GCC diagnostic pop
-#endif
+        JSON_HEDLEY_DIAGNOSTIC_POP
    }

    /// @brief comparison: equal
@@ -3862,14 +3860,12 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
    /// @sa https://json.nlohmann.me/api/basic_json/operator_eq/
    friend bool operator==(const_reference lhs, const_reference rhs) noexcept
    {
+        JSON_HEDLEY_DIAGNOSTIC_PUSH
 #ifdef __GNUC__
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wfloat-equal"
+        JSON_HEDLEY_PRAGMA(GCC diagnostic ignored "-Wfloat-equal")
 #endif
        JSON_IMPLEMENT_OPERATOR( ==, true, false, false)
-#ifdef __GNUC__
-#pragma GCC diagnostic pop
-#endif
+        JSON_HEDLEY_DIAGNOSTIC_POP
    }

    /// @brief comparison: equal
@@ -4944,9 +4944,9 @@ NLOHMANN_JSON_NAMESPACE_END
 // functions to. As a result, we suppress this warning here to avoid client
 // code stumbling over this. See https://github.com/nlohmann/json/issues/4087
 // for a discussion.
+JSON_HEDLEY_DIAGNOSTIC_PUSH
 #if defined(__clang__)
-    #pragma clang diagnostic push
-    #pragma clang diagnostic ignored "-Wweak-vtables"
+    JSON_HEDLEY_PRAGMA(clang diagnostic ignored "-Wweak-vtables")
 #endif

 NLOHMANN_JSON_NAMESPACE_BEGIN
@@ -5198,9 +5198,7 @@ class other_error : public exception
 }  // namespace detail
 NLOHMANN_JSON_NAMESPACE_END

-#if defined(__clang__)
-    #pragma clang diagnostic pop
-#endif
+JSON_HEDLEY_DIAGNOSTIC_POP

 // #include <nlohmann/detail/macro_scope.hpp>

@@ -5975,6 +5973,8 @@ NLOHMANN_JSON_NAMESPACE_END

 // #include <nlohmann/detail/abi_macros.hpp>

+// #include <nlohmann/detail/macro_scope.hpp>
+
 // #include <nlohmann/detail/meta/type_traits.hpp>

 // #include <nlohmann/detail/string_utils.hpp>
@@ -6204,10 +6204,10 @@ NLOHMANN_JSON_NAMESPACE_END
 namespace std
 {

+// Fix: https://github.com/nlohmann/json/issues/1401
+JSON_HEDLEY_DIAGNOSTIC_PUSH
 #if defined(__clang__)
-    // Fix: https://github.com/nlohmann/json/issues/1401
-    #pragma clang diagnostic push
-    #pragma clang diagnostic ignored "-Wmismatched-tags"
+    JSON_HEDLEY_PRAGMA(clang diagnostic ignored "-Wmismatched-tags")
 #endif
 template<typename IteratorType>
 class tuple_size<::nlohmann::detail::iteration_proxy_value<IteratorType>> // NOLINT(cert-dcl58-cpp)
@@ -6221,9 +6221,7 @@ class tuple_element<N, ::nlohmann::detail::iteration_proxy_value<IteratorType >>
                     get<N>(std::declval <
                            ::nlohmann::detail::iteration_proxy_value<IteratorType >> ()));
 };
-#if defined(__clang__)
-    #pragma clang diagnostic pop
-#endif
+JSON_HEDLEY_DIAGNOSTIC_POP

 }  // namespace std

@@ -18857,9 +18855,9 @@ class binary_writer

    void write_compact_float(const number_float_t n, detail::input_format_t format)
    {
+        JSON_HEDLEY_DIAGNOSTIC_PUSH
 #ifdef __GNUC__
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wfloat-equal"
+        JSON_HEDLEY_PRAGMA(GCC diagnostic ignored "-Wfloat-equal")
 #endif
        if (!std::isfinite(n) || ((static_cast<double>(n) >= static_cast<double>(std::numeric_limits<float>::lowest()) &&
                                   static_cast<double>(n) <= static_cast<double>((std::numeric_limits<float>::max)()) &&
@@ -18877,9 +18875,7 @@ class binary_writer
                                : get_msgpack_float_prefix(n));
            write_number(n);
        }
-#ifdef __GNUC__
-#pragma GCC diagnostic pop
-#endif
+        JSON_HEDLEY_DIAGNOSTIC_POP
    }

  public:
@@ -20052,9 +20048,9 @@ char* to_chars(char* first, const char* last, FloatType value)
        *first++ = '-';
    }

+    JSON_HEDLEY_DIAGNOSTIC_PUSH
 #ifdef __GNUC__
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wfloat-equal"
+    JSON_HEDLEY_PRAGMA(GCC diagnostic ignored "-Wfloat-equal")
 #endif
    if (value == 0) // +-0
    {
@@ -20064,9 +20060,7 @@ char* to_chars(char* first, const char* last, FloatType value)
        *first++ = '0';
        return first;
    }
-#ifdef __GNUC__
-#pragma GCC diagnostic pop
-#endif
+    JSON_HEDLEY_DIAGNOSTIC_POP

    JSON_ASSERT(last - first >= std::numeric_limits<FloatType>::max_digits10);

@@ -25197,15 +25191,13 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
    /// @sa https://json.nlohmann.me/api/basic_json/operator_eq/
    bool operator==(const_reference rhs) const noexcept
    {
+        JSON_HEDLEY_DIAGNOSTIC_PUSH
 #ifdef __GNUC__
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wfloat-equal"
+        JSON_HEDLEY_PRAGMA(GCC diagnostic ignored "-Wfloat-equal")
 #endif
        const_reference lhs = *this;
        JSON_IMPLEMENT_OPERATOR( ==, true, false, false)
-#ifdef __GNUC__
-#pragma GCC diagnostic pop
-#endif
+        JSON_HEDLEY_DIAGNOSTIC_POP
    }

    /// @brief comparison: equal
@@ -25290,14 +25282,12 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
    /// @sa https://json.nlohmann.me/api/basic_json/operator_eq/
    friend bool operator==(const_reference lhs, const_reference rhs) noexcept
    {
+        JSON_HEDLEY_DIAGNOSTIC_PUSH
 #ifdef __GNUC__
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wfloat-equal"
+        JSON_HEDLEY_PRAGMA(GCC diagnostic ignored "-Wfloat-equal")
 #endif
        JSON_IMPLEMENT_OPERATOR( ==, true, false, false)
-#ifdef __GNUC__
-#pragma GCC diagnostic pop
-#endif
+        JSON_HEDLEY_DIAGNOSTIC_POP
    }

    /// @brief comparison: equal
@@ -125,51 +125,6 @@ json_test_set_test_options(test-unicode4 TEST_PROPERTIES TIMEOUT 3000)
 # add unit tests
 #############################################################################

-# Generate the leak checks for every JSON_HEDLEY_* macro defined in
-# hedley.hpp; tests/src/unit-no-macro-leak.cpp #include-s the result after
-# nlohmann/json.hpp (see issue #5408). Using the shared
-# cmake/scripts/gen_hedley_undef_check.cmake script (also used by `make
-# update_hedley_undef`) instead of a hand-maintained list of macro names
-# means this test can never go stale after a future `make update_hedley`.
-set(hedley_hpp "${PROJECT_SOURCE_DIR}/include/nlohmann/thirdparty/hedley/hedley.hpp")
-set(hedley_undef_check_script "${PROJECT_SOURCE_DIR}/cmake/scripts/gen_hedley_undef_check.cmake")
-set(hedley_undef_checks "${PROJECT_BINARY_DIR}/include/hedley_undef_checks.inc")
-
-# Reconfigure whenever the vendored header or the generator script changes,
-# so a `cmake --build` after `make update_hedley` does not silently keep a
-# stale generated file around.
-set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS
-    "${hedley_hpp}"
-    "${hedley_undef_check_script}")
-
-# Generate once at configure time, so the very first build (before any
-# custom-command build step has run) already has an up-to-date file.
-execute_process(
-    COMMAND ${CMAKE_COMMAND}
-        "-DHEDLEY_HPP=${hedley_hpp}"
-        "-DOUTPUT=${hedley_undef_checks}"
-        -DMODE=checks
-        -P "${hedley_undef_check_script}"
-    RESULT_VARIABLE hedley_undef_check_result
-)
-if(NOT hedley_undef_check_result EQUAL 0)
-    message(FATAL_ERROR "Failed to generate ${hedley_undef_checks}")
-endif()
-
-# Also (re)generate as a build step, so an incremental build after editing
-# hedley.hpp without a full reconfigure still picks up the change.
-add_custom_command(
-    OUTPUT "${hedley_undef_checks}"
-    COMMAND ${CMAKE_COMMAND}
-        "-DHEDLEY_HPP=${hedley_hpp}"
-        "-DOUTPUT=${hedley_undef_checks}"
-        -DMODE=checks
-        -P "${hedley_undef_check_script}"
-    DEPENDS "${hedley_hpp}" "${hedley_undef_check_script}"
-    COMMENT "Generating Hedley undef leak checks"
-    VERBATIM)
-add_custom_target(generate_hedley_undef_checks DEPENDS "${hedley_undef_checks}")
-
 if("${JSON_TestStandards}" STREQUAL "")
    set(test_cxx_standards 11 14 17 20 23)
    unset(test_force)
@@ -208,14 +163,6 @@ foreach(file ${files})
    json_test_add_test_for(${file} MAIN test_main CXX_STANDARDS ${test_cxx_standards} ${test_force})
 endforeach()

-# tests/src/unit-no-macro-leak.cpp #include-s the generated leak-check file,
-# so its test targets must be built after generate_hedley_undef_checks.
-foreach(cxx_standard ${test_cxx_standards})
-    if(TARGET test-no-macro-leak_cpp${cxx_standard})
-        add_dependencies(test-no-macro-leak_cpp${cxx_standard} generate_hedley_undef_checks)
-    endif()
-endforeach()
-
 if(json_32bit_test_only)
    # Skip all other tests in this file
    return()
@@ -16,19 +16,471 @@
 // and JSON_HEDLEY_CLANG_HAS_DECLSPEC_ATTRIBUTE escaped this cleanup because
 // hedley_undef.hpp had no matching #undef for them.
 //
-// hedley_undef_checks.inc (included below) is generated at CMake configure/
-// build time by cmake/scripts/gen_hedley_undef_check.cmake, which derives the
-// full list of JSON_HEDLEY_* macro names directly from hedley.hpp. That way
-// this test covers every macro Hedley actually defines -- not a hardcoded
-// snapshot that would silently go stale the next time `make update_hedley`
-// runs -- and can never drift from the vendored header.
+// The #ifdef/#error checks below are mechanically derived from the full list
+// of macro names in hedley_undef.hpp, so every JSON_HEDLEY_* macro is covered
+// -- not just the four that leaked historically.

 #include "doctest_compatibility.h"

 #include <nlohmann/json.hpp>

-TEST_CASE("JSON_HEDLEY macros do not leak after including json.hpp")
+#ifdef JSON_HEDLEY_ALWAYS_INLINE
+    #error "JSON_HEDLEY_ALWAYS_INLINE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_ARM_VERSION
+    #error "JSON_HEDLEY_ARM_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_ARM_VERSION_CHECK
+    #error "JSON_HEDLEY_ARM_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_ARRAY_PARAM
+    #error "JSON_HEDLEY_ARRAY_PARAM must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_ASSUME
+    #error "JSON_HEDLEY_ASSUME must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_BEGIN_C_DECLS
+    #error "JSON_HEDLEY_BEGIN_C_DECLS must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CLANG_HAS_ATTRIBUTE
+    #error "JSON_HEDLEY_CLANG_HAS_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CLANG_HAS_BUILTIN
+    #error "JSON_HEDLEY_CLANG_HAS_BUILTIN must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CLANG_HAS_CPP_ATTRIBUTE
+    #error "JSON_HEDLEY_CLANG_HAS_CPP_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CLANG_HAS_DECLSPEC_ATTRIBUTE
+    #error "JSON_HEDLEY_CLANG_HAS_DECLSPEC_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CLANG_HAS_EXTENSION
+    #error "JSON_HEDLEY_CLANG_HAS_EXTENSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CLANG_HAS_FEATURE
+    #error "JSON_HEDLEY_CLANG_HAS_FEATURE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CLANG_HAS_WARNING
+    #error "JSON_HEDLEY_CLANG_HAS_WARNING must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_COMPCERT_VERSION
+    #error "JSON_HEDLEY_COMPCERT_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_COMPCERT_VERSION_CHECK
+    #error "JSON_HEDLEY_COMPCERT_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CONCAT
+    #error "JSON_HEDLEY_CONCAT must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CONCAT3
+    #error "JSON_HEDLEY_CONCAT3 must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CONCAT3_EX
+    #error "JSON_HEDLEY_CONCAT3_EX must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CONCAT_EX
+    #error "JSON_HEDLEY_CONCAT_EX must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CONST
+    #error "JSON_HEDLEY_CONST must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CONSTEXPR
+    #error "JSON_HEDLEY_CONSTEXPR must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CONST_CAST
+    #error "JSON_HEDLEY_CONST_CAST must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CPP_CAST
+    #error "JSON_HEDLEY_CPP_CAST must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CRAY_VERSION
+    #error "JSON_HEDLEY_CRAY_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_CRAY_VERSION_CHECK
+    #error "JSON_HEDLEY_CRAY_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_C_DECL
+    #error "JSON_HEDLEY_C_DECL must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DEPRECATED
+    #error "JSON_HEDLEY_DEPRECATED must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DEPRECATED_FOR
+    #error "JSON_HEDLEY_DEPRECATED_FOR must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DIAGNOSTIC_DISABLE_CAST_QUAL
+    #error "JSON_HEDLEY_DIAGNOSTIC_DISABLE_CAST_QUAL must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_
+    #error "JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_ must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED
+    #error "JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES
+    #error "JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS
+    #error "JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNUSED_FUNCTION
+    #error "JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNUSED_FUNCTION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DIAGNOSTIC_POP
+    #error "JSON_HEDLEY_DIAGNOSTIC_POP must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DIAGNOSTIC_PUSH
+    #error "JSON_HEDLEY_DIAGNOSTIC_PUSH must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DMC_VERSION
+    #error "JSON_HEDLEY_DMC_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_DMC_VERSION_CHECK
+    #error "JSON_HEDLEY_DMC_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_EMPTY_BASES
+    #error "JSON_HEDLEY_EMPTY_BASES must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_EMSCRIPTEN_VERSION
+    #error "JSON_HEDLEY_EMSCRIPTEN_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_EMSCRIPTEN_VERSION_CHECK
+    #error "JSON_HEDLEY_EMSCRIPTEN_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_END_C_DECLS
+    #error "JSON_HEDLEY_END_C_DECLS must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_FALL_THROUGH
+    #error "JSON_HEDLEY_FALL_THROUGH must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_FLAGS
+    #error "JSON_HEDLEY_FLAGS must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_FLAGS_CAST
+    #error "JSON_HEDLEY_FLAGS_CAST must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GCC_HAS_ATTRIBUTE
+    #error "JSON_HEDLEY_GCC_HAS_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GCC_HAS_BUILTIN
+    #error "JSON_HEDLEY_GCC_HAS_BUILTIN must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GCC_HAS_CPP_ATTRIBUTE
+    #error "JSON_HEDLEY_GCC_HAS_CPP_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GCC_HAS_DECLSPEC_ATTRIBUTE
+    #error "JSON_HEDLEY_GCC_HAS_DECLSPEC_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GCC_HAS_EXTENSION
+    #error "JSON_HEDLEY_GCC_HAS_EXTENSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GCC_HAS_FEATURE
+    #error "JSON_HEDLEY_GCC_HAS_FEATURE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GCC_HAS_WARNING
+    #error "JSON_HEDLEY_GCC_HAS_WARNING must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GCC_NOT_CLANG_VERSION_CHECK
+    #error "JSON_HEDLEY_GCC_NOT_CLANG_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GCC_VERSION
+    #error "JSON_HEDLEY_GCC_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GCC_VERSION_CHECK
+    #error "JSON_HEDLEY_GCC_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GNUC_HAS_ATTRIBUTE
+    #error "JSON_HEDLEY_GNUC_HAS_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GNUC_HAS_BUILTIN
+    #error "JSON_HEDLEY_GNUC_HAS_BUILTIN must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GNUC_HAS_CPP_ATTRIBUTE
+    #error "JSON_HEDLEY_GNUC_HAS_CPP_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GNUC_HAS_DECLSPEC_ATTRIBUTE
+    #error "JSON_HEDLEY_GNUC_HAS_DECLSPEC_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GNUC_HAS_EXTENSION
+    #error "JSON_HEDLEY_GNUC_HAS_EXTENSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GNUC_HAS_FEATURE
+    #error "JSON_HEDLEY_GNUC_HAS_FEATURE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GNUC_HAS_WARNING
+    #error "JSON_HEDLEY_GNUC_HAS_WARNING must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GNUC_VERSION
+    #error "JSON_HEDLEY_GNUC_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_GNUC_VERSION_CHECK
+    #error "JSON_HEDLEY_GNUC_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_HAS_ATTRIBUTE
+    #error "JSON_HEDLEY_HAS_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_HAS_BUILTIN
+    #error "JSON_HEDLEY_HAS_BUILTIN must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_HAS_CPP_ATTRIBUTE
+    #error "JSON_HEDLEY_HAS_CPP_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_HAS_CPP_ATTRIBUTE_NS
+    #error "JSON_HEDLEY_HAS_CPP_ATTRIBUTE_NS must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_HAS_DECLSPEC_ATTRIBUTE
+    #error "JSON_HEDLEY_HAS_DECLSPEC_ATTRIBUTE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_HAS_EXTENSION
+    #error "JSON_HEDLEY_HAS_EXTENSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_HAS_FEATURE
+    #error "JSON_HEDLEY_HAS_FEATURE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_HAS_WARNING
+    #error "JSON_HEDLEY_HAS_WARNING must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_IAR_VERSION
+    #error "JSON_HEDLEY_IAR_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_IAR_VERSION_CHECK
+    #error "JSON_HEDLEY_IAR_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_IBM_VERSION
+    #error "JSON_HEDLEY_IBM_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_IBM_VERSION_CHECK
+    #error "JSON_HEDLEY_IBM_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_IMPORT
+    #error "JSON_HEDLEY_IMPORT must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_INLINE
+    #error "JSON_HEDLEY_INLINE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_INTEL_CL_VERSION
+    #error "JSON_HEDLEY_INTEL_CL_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_INTEL_CL_VERSION_CHECK
+    #error "JSON_HEDLEY_INTEL_CL_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_INTEL_VERSION
+    #error "JSON_HEDLEY_INTEL_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_INTEL_VERSION_CHECK
+    #error "JSON_HEDLEY_INTEL_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_IS_CONSTANT
+    #error "JSON_HEDLEY_IS_CONSTANT must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_IS_CONSTEXPR_
+    #error "JSON_HEDLEY_IS_CONSTEXPR_ must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_LIKELY
+    #error "JSON_HEDLEY_LIKELY must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_MALLOC
+    #error "JSON_HEDLEY_MALLOC must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_MCST_LCC_VERSION
+    #error "JSON_HEDLEY_MCST_LCC_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_MCST_LCC_VERSION_CHECK
+    #error "JSON_HEDLEY_MCST_LCC_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_MESSAGE
+    #error "JSON_HEDLEY_MESSAGE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_MSVC_VERSION
+    #error "JSON_HEDLEY_MSVC_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_MSVC_VERSION_CHECK
+    #error "JSON_HEDLEY_MSVC_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_NEVER_INLINE
+    #error "JSON_HEDLEY_NEVER_INLINE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_NON_NULL
+    #error "JSON_HEDLEY_NON_NULL must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_NO_ESCAPE
+    #error "JSON_HEDLEY_NO_ESCAPE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_NO_RETURN
+    #error "JSON_HEDLEY_NO_RETURN must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_NO_THROW
+    #error "JSON_HEDLEY_NO_THROW must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_NULL
+    #error "JSON_HEDLEY_NULL must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PELLES_VERSION
+    #error "JSON_HEDLEY_PELLES_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PELLES_VERSION_CHECK
+    #error "JSON_HEDLEY_PELLES_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PGI_VERSION
+    #error "JSON_HEDLEY_PGI_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PGI_VERSION_CHECK
+    #error "JSON_HEDLEY_PGI_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PRAGMA
+    #error "JSON_HEDLEY_PRAGMA must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PREDICT
+    #error "JSON_HEDLEY_PREDICT must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PREDICT_FALSE
+    #error "JSON_HEDLEY_PREDICT_FALSE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PREDICT_TRUE
+    #error "JSON_HEDLEY_PREDICT_TRUE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PRINTF_FORMAT
+    #error "JSON_HEDLEY_PRINTF_FORMAT must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PRIVATE
+    #error "JSON_HEDLEY_PRIVATE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PUBLIC
+    #error "JSON_HEDLEY_PUBLIC must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_PURE
+    #error "JSON_HEDLEY_PURE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_REINTERPRET_CAST
+    #error "JSON_HEDLEY_REINTERPRET_CAST must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_REQUIRE
+    #error "JSON_HEDLEY_REQUIRE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_REQUIRE_CONSTEXPR
+    #error "JSON_HEDLEY_REQUIRE_CONSTEXPR must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_REQUIRE_MSG
+    #error "JSON_HEDLEY_REQUIRE_MSG must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_RESTRICT
+    #error "JSON_HEDLEY_RESTRICT must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_RETURNS_NON_NULL
+    #error "JSON_HEDLEY_RETURNS_NON_NULL must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_SENTINEL
+    #error "JSON_HEDLEY_SENTINEL must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_STATIC_ASSERT
+    #error "JSON_HEDLEY_STATIC_ASSERT must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_STATIC_CAST
+    #error "JSON_HEDLEY_STATIC_CAST must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_STRINGIFY
+    #error "JSON_HEDLEY_STRINGIFY must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_STRINGIFY_EX
+    #error "JSON_HEDLEY_STRINGIFY_EX must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_SUNPRO_VERSION
+    #error "JSON_HEDLEY_SUNPRO_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_SUNPRO_VERSION_CHECK
+    #error "JSON_HEDLEY_SUNPRO_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TINYC_VERSION
+    #error "JSON_HEDLEY_TINYC_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TINYC_VERSION_CHECK
+    #error "JSON_HEDLEY_TINYC_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_ARMCL_VERSION
+    #error "JSON_HEDLEY_TI_ARMCL_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_ARMCL_VERSION_CHECK
+    #error "JSON_HEDLEY_TI_ARMCL_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_CL2000_VERSION
+    #error "JSON_HEDLEY_TI_CL2000_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_CL2000_VERSION_CHECK
+    #error "JSON_HEDLEY_TI_CL2000_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_CL430_VERSION
+    #error "JSON_HEDLEY_TI_CL430_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_CL430_VERSION_CHECK
+    #error "JSON_HEDLEY_TI_CL430_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_CL6X_VERSION
+    #error "JSON_HEDLEY_TI_CL6X_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_CL6X_VERSION_CHECK
+    #error "JSON_HEDLEY_TI_CL6X_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_CL7X_VERSION
+    #error "JSON_HEDLEY_TI_CL7X_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_CL7X_VERSION_CHECK
+    #error "JSON_HEDLEY_TI_CL7X_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_CLPRU_VERSION
+    #error "JSON_HEDLEY_TI_CLPRU_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_CLPRU_VERSION_CHECK
+    #error "JSON_HEDLEY_TI_CLPRU_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_VERSION
+    #error "JSON_HEDLEY_TI_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_TI_VERSION_CHECK
+    #error "JSON_HEDLEY_TI_VERSION_CHECK must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_UNAVAILABLE
+    #error "JSON_HEDLEY_UNAVAILABLE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_UNLIKELY
+    #error "JSON_HEDLEY_UNLIKELY must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_UNPREDICTABLE
+    #error "JSON_HEDLEY_UNPREDICTABLE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_UNREACHABLE
+    #error "JSON_HEDLEY_UNREACHABLE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_UNREACHABLE_RETURN
+    #error "JSON_HEDLEY_UNREACHABLE_RETURN must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_VERSION
+    #error "JSON_HEDLEY_VERSION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_VERSION_DECODE_MAJOR
+    #error "JSON_HEDLEY_VERSION_DECODE_MAJOR must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_VERSION_DECODE_MINOR
+    #error "JSON_HEDLEY_VERSION_DECODE_MINOR must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_VERSION_DECODE_REVISION
+    #error "JSON_HEDLEY_VERSION_DECODE_REVISION must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_VERSION_ENCODE
+    #error "JSON_HEDLEY_VERSION_ENCODE must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_WARNING
+    #error "JSON_HEDLEY_WARNING must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_WARN_UNUSED_RESULT
+    #error "JSON_HEDLEY_WARN_UNUSED_RESULT must not remain defined after including json.hpp"
+#endif
+#ifdef JSON_HEDLEY_WARN_UNUSED_RESULT_MSG
+    #error "JSON_HEDLEY_WARN_UNUSED_RESULT_MSG must not remain defined after including json.hpp"
+#endif
+
+TEST_CASE("no JSON_HEDLEY_* macro leaks after including json.hpp")
 {
-#include "hedley_undef_checks.inc"
-    CHECK(true); // keep an assertion when nothing leaked
+    // if this test compiles at all, none of the JSON_HEDLEY_* macros checked
+    // above remained defined after including <nlohmann/json.hpp>
+    CHECK(true);
 }