diff --git a/core/config/project_settings.cpp b/core/config/project_settings.cpp
index bed2f08cbc..ff111b1fad 100644
--- a/core/config/project_settings.cpp
+++ b/core/config/project_settings.cpp
@@ -30,8 +30,8 @@
 
 #include "project_settings.h"
 
-#include "core/core_bind.h" // For Compression enum.
 #include "core/input/input_map.h"
+#include "core/io/compression.h"
 #include "core/io/config_file.h"
 #include "core/io/dir_access.h"
 #include "core/io/file_access.h"
@@ -50,7 +50,7 @@
 
 #ifdef TOOLS_ENABLED
 #include "core/config/engine.h"
-#include "modules/modules_enabled.gen.h" // For mono.
+#include "modules/modules_enabled.gen.h" // IWYU pragma: keep. For mono.
 #endif // TOOLS_ENABLED
 
 ProjectSettings *ProjectSettings::get_singleton() {
diff --git a/core/config/project_settings.h b/core/config/project_settings.h
index 6b30ab0659..e197a8d93b 100644
--- a/core/config/project_settings.h
+++ b/core/config/project_settings.h
@@ -31,6 +31,7 @@
 #pragma once
 
 #include "core/object/object.h"
+#include "core/os/thread_safe.h"
 #include "core/templates/rb_map.h"
 
 template <typename T>
diff --git a/core/core_builders.py b/core/core_builders.py
index bfae638a64..c9d76eb068 100644
--- a/core/core_builders.py
+++ b/core/core_builders.py
@@ -63,7 +63,7 @@ def encryption_key_builder(target, source, env):
     with methods.generated_wrapper(str(target[0])) as file:
         file.write(
             f"""\
-#include "core/config/project_settings.h"
+#include <cstdint>
 
 uint8_t script_encryption_key[32] = {{
 	{methods.format_buffer(buffer, 1)}
diff --git a/core/core_constants.cpp b/core/core_constants.cpp
index 7c6d99c1cc..b99da1fe2d 100644
--- a/core/core_constants.cpp
+++ b/core/core_constants.cpp
@@ -30,10 +30,13 @@
 
 #include "core_constants.h"
 
-#include "core/input/input_event.h"
-#include "core/object/class_db.h"
+#include "core/input/input_enums.h"
+#include "core/object/method_bind.h" // IWYU pragma: keep. To bind `MethodFlags`.
+#include "core/object/object.h"
 #include "core/os/keyboard.h"
+#include "core/variant/type_info.h"
 #include "core/variant/variant.h"
+#include "core/variant/variant_caster.h"
 
 struct _CoreConstant {
 #ifdef DEBUG_ENABLED
diff --git a/core/crypto/crypto_core.cpp b/core/crypto/crypto_core.cpp
index 9d2c346e3a..1c7d5d0790 100644
--- a/core/crypto/crypto_core.cpp
+++ b/core/crypto/crypto_core.cpp
@@ -31,6 +31,7 @@
 #include "crypto_core.h"
 
 #include "core/os/os.h"
+#include "core/string/ustring.h"
 
 #include <mbedtls/aes.h>
 #include <mbedtls/base64.h>
diff --git a/core/crypto/crypto_core.h b/core/crypto/crypto_core.h
index 8ef50fbcf7..a061a74387 100644
--- a/core/crypto/crypto_core.h
+++ b/core/crypto/crypto_core.h
@@ -30,7 +30,12 @@
 
 #pragma once
 
-#include "core/object/ref_counted.h"
+#include "core/error/error_list.h"
+
+#include <cstddef>
+#include <cstdint>
+
+class String;
 
 class CryptoCore {
 public:
diff --git a/core/debugger/engine_profiler.cpp b/core/debugger/engine_profiler.cpp
index 613525f0e7..d93a367f15 100644
--- a/core/debugger/engine_profiler.cpp
+++ b/core/debugger/engine_profiler.cpp
@@ -31,7 +31,7 @@
 #include "engine_profiler.h"
 
 #include "core/debugger/engine_debugger.h"
-#include "core/object/class_db.h"
+#include "core/object/class_db.h" // IWYU pragma: keep. `GDVIRTUAL_BIND` macro.
 
 void EngineProfiler::_bind_methods() {
 	GDVIRTUAL_BIND(_toggle, "enable", "options");
diff --git a/core/debugger/local_debugger.h b/core/debugger/local_debugger.h
index 5c603e5f86..91c8d8be40 100644
--- a/core/debugger/local_debugger.h
+++ b/core/debugger/local_debugger.h
@@ -31,7 +31,6 @@
 #pragma once
 
 #include "core/debugger/engine_debugger.h"
-#include "core/object/script_language.h"
 #include "core/templates/list.h"
 
 class LocalDebugger : public EngineDebugger {
diff --git a/core/debugger/remote_debugger.h b/core/debugger/remote_debugger.h
index 8ecc1c483f..9c64342a02 100644
--- a/core/debugger/remote_debugger.h
+++ b/core/debugger/remote_debugger.h
@@ -33,7 +33,6 @@
 #include "core/debugger/debugger_marshalls.h"
 #include "core/debugger/engine_debugger.h"
 #include "core/debugger/remote_debugger_peer.h"
-#include "core/string/string_name.h"
 #include "core/string/ustring.h"
 #include "core/variant/array.h"
 
diff --git a/core/debugger/remote_debugger_peer.cpp b/core/debugger/remote_debugger_peer.cpp
index 759394a2a5..19dea3ec04 100644
--- a/core/debugger/remote_debugger_peer.cpp
+++ b/core/debugger/remote_debugger_peer.cpp
@@ -32,6 +32,9 @@
 
 #include "core/config/project_settings.h"
 #include "core/io/marshalls.h"
+#include "core/io/stream_peer_socket.h"
+#include "core/io/stream_peer_tcp.h"
+#include "core/io/stream_peer_uds.h"
 #include "core/os/os.h"
 
 bool RemoteDebuggerPeerTCP::is_peer_connected() {
diff --git a/core/debugger/remote_debugger_peer.h b/core/debugger/remote_debugger_peer.h
index 6942c09bf9..dec7d91106 100644
--- a/core/debugger/remote_debugger_peer.h
+++ b/core/debugger/remote_debugger_peer.h
@@ -30,13 +30,13 @@
 
 #pragma once
 
-#include "core/io/stream_peer_tcp.h"
-#include "core/io/stream_peer_uds.h"
 #include "core/object/ref_counted.h"
 #include "core/os/mutex.h"
 #include "core/os/thread.h"
 #include "core/string/ustring.h"
 
+class StreamPeerSocket;
+
 class RemoteDebuggerPeer : public RefCounted {
 	GDSOFTCLASS(RemoteDebuggerPeer, RefCounted);
 
diff --git a/core/doc_data.cpp b/core/doc_data.cpp
index 92de0a8070..9cd8e51b61 100644
--- a/core/doc_data.cpp
+++ b/core/doc_data.cpp
@@ -30,6 +30,8 @@
 
 #include "doc_data.h"
 
+#include "core/object/object.h"
+
 String DocData::get_default_value_string(const Variant &p_value) {
 	const Variant::Type type = p_value.get_type();
 	if (type == Variant::ARRAY) {
diff --git a/core/doc_data.h b/core/doc_data.h
index 80b7fa2382..c0aa165212 100644
--- a/core/doc_data.h
+++ b/core/doc_data.h
@@ -30,7 +30,6 @@
 
 #pragma once
 
-#include "core/io/xml_parser.h"
 #include "core/variant/variant.h"
 
 class DocData {
diff --git a/core/extension/extension_api_dump.h b/core/extension/extension_api_dump.h
index 027a8d916e..1f6e1de454 100644
--- a/core/extension/extension_api_dump.h
+++ b/core/extension/extension_api_dump.h
@@ -30,14 +30,17 @@
 
 #pragma once
 
-#include "core/extension/gdextension.h"
-
 #ifdef TOOLS_ENABLED
 
+#include "core/error/error_list.h"
+#include "core/string/ustring.h"
+#include "core/variant/dictionary.h"
+
 class GDExtensionAPIDump {
 public:
 	static Dictionary generate_extension_api(bool p_include_docs = false);
 	static void generate_extension_json_file(const String &p_path, bool p_include_docs = false);
 	static Error validate_extension_json_file(const String &p_path);
 };
+
 #endif
diff --git a/core/extension/gdextension.h b/core/extension/gdextension.h
index 2f0835a0d2..8bf3ebe6c3 100644
--- a/core/extension/gdextension.h
+++ b/core/extension/gdextension.h
@@ -32,7 +32,6 @@
 
 #include "core/extension/gdextension_interface.gen.h"
 #include "core/extension/gdextension_loader.h"
-#include "core/io/config_file.h"
 #include "core/io/resource_loader.h"
 #include "core/object/ref_counted.h"
 
diff --git a/core/extension/gdextension_function_loader.h b/core/extension/gdextension_function_loader.h
index febda097ca..5635a24d01 100644
--- a/core/extension/gdextension_function_loader.h
+++ b/core/extension/gdextension_function_loader.h
@@ -31,7 +31,6 @@
 #pragma once
 
 #include "core/extension/gdextension_loader.h"
-#include "core/os/shared_object.h"
 
 class GDExtension;
 
diff --git a/core/io/compression.cpp b/core/io/compression.cpp
index aeed0d272b..72d2e1b222 100644
--- a/core/io/compression.cpp
+++ b/core/io/compression.cpp
@@ -30,7 +30,6 @@
 
 #include "compression.h"
 
-#include "core/config/project_settings.h"
 #include "core/io/zip_io.h"
 
 #include "thirdparty/misc/fastlz.h"
diff --git a/core/io/delta_encoding.cpp b/core/io/delta_encoding.cpp
index 9b5242a60e..d4db12a467 100644
--- a/core/io/delta_encoding.cpp
+++ b/core/io/delta_encoding.cpp
@@ -30,6 +30,10 @@
 
 #include "delta_encoding.h"
 
+#include "core/error/error_list.h"
+#include "core/templates/vector.h"
+#include "core/variant/variant.h" // vformat
+
 #include <zstd.h>
 
 #define ERR_FAIL_ZSTD_V_MSG(m_result, m_retval, m_msg) \
diff --git a/core/io/delta_encoding.h b/core/io/delta_encoding.h
index 835f1e8409..7d2253055e 100644
--- a/core/io/delta_encoding.h
+++ b/core/io/delta_encoding.h
@@ -30,7 +30,12 @@
 
 #pragma once
 
-#include "core/io/file_access.h"
+#include "core/templates/span.h"
+
+#include <cstdint>
+
+template <typename T>
+class Vector;
 
 class DeltaEncoding {
 public:
diff --git a/core/io/dtls_server.h b/core/io/dtls_server.h
index 10965b3b88..416a76a067 100644
--- a/core/io/dtls_server.h
+++ b/core/io/dtls_server.h
@@ -30,7 +30,6 @@
 
 #pragma once
 
-#include "core/io/net_socket.h"
 #include "core/io/packet_peer_dtls.h"
 
 class DTLSServer : public RefCounted {
diff --git a/core/io/http_client.h b/core/io/http_client.h
index 54a3d9c436..d2da1e6a6f 100644
--- a/core/io/http_client.h
+++ b/core/io/http_client.h
@@ -31,9 +31,7 @@
 #pragma once
 
 #include "core/crypto/crypto.h"
-#include "core/io/ip.h"
 #include "core/io/stream_peer.h"
-#include "core/io/stream_peer_tcp.h"
 #include "core/object/ref_counted.h"
 
 class HTTPClient : public RefCounted {
diff --git a/core/io/http_client_tcp.cpp b/core/io/http_client_tcp.cpp
index 68010fa2f7..13f487e13c 100644
--- a/core/io/http_client_tcp.cpp
+++ b/core/io/http_client_tcp.cpp
@@ -32,6 +32,7 @@
 
 #include "http_client_tcp.h"
 
+#include "core/io/stream_peer_tcp.h"
 #include "core/io/stream_peer_tls.h"
 #include "core/object/class_db.h"
 #include "core/os/os.h"
diff --git a/core/io/http_client_tcp.h b/core/io/http_client_tcp.h
index 84f9bcc16b..ae6f3b453a 100644
--- a/core/io/http_client_tcp.h
+++ b/core/io/http_client_tcp.h
@@ -33,6 +33,9 @@
 #include "http_client.h"
 
 #include "core/crypto/crypto.h"
+#include "core/io/ip.h"
+
+class StreamPeerTCP;
 
 class HTTPClientTCP : public HTTPClient {
 	GDSOFTCLASS(HTTPClientTCP, HTTPClient);
diff --git a/core/io/packet_peer_udp.h b/core/io/packet_peer_udp.h
index 1c909860c5..ef005b0854 100644
--- a/core/io/packet_peer_udp.h
+++ b/core/io/packet_peer_udp.h
@@ -30,7 +30,7 @@
 
 #pragma once
 
-#include "core/io/ip.h"
+#include "core/io/ip_address.h"
 #include "core/io/net_socket.h"
 #include "core/io/packet_peer.h"
 
diff --git a/core/io/resource.cpp b/core/io/resource.cpp
index a19f0d816f..d4cdee23cc 100644
--- a/core/io/resource.cpp
+++ b/core/io/resource.cpp
@@ -35,7 +35,7 @@
 #include "core/math/random_pcg.h"
 #include "core/object/class_db.h"
 #include "core/os/os.h"
-#include "core/variant/container_type_validate.h"
+#include "core/variant/container_type_validate.h" // IWYU pragma: keep.
 #include "scene/main/node.h" //only so casting works
 
 void Resource::register_custom_data_to_otdb() {
diff --git a/core/io/resource.h b/core/io/resource.h
index b83badf030..dd432b9db7 100644
--- a/core/io/resource.h
+++ b/core/io/resource.h
@@ -30,7 +30,7 @@
 
 #pragma once
 
-#include "core/io/resource_uid.h"
+#include "core/io/resource_uid.h" // IWYU pragma: export. Make available to all resources.
 #include "core/object/gdvirtual.gen.h"
 #include "core/object/ref_counted.h"
 #include "core/templates/self_list.h"
diff --git a/core/io/stream_peer_gzip.h b/core/io/stream_peer_gzip.h
index 9641f778b9..4d5a84f879 100644
--- a/core/io/stream_peer_gzip.h
+++ b/core/io/stream_peer_gzip.h
@@ -32,7 +32,6 @@
 
 #include "core/io/stream_peer.h"
 
-#include "core/io/compression.h"
 #include "core/templates/ring_buffer.h"
 
 class StreamPeerGZIP : public StreamPeer {
diff --git a/core/io/stream_peer_tcp.h b/core/io/stream_peer_tcp.h
index e472a46cf0..62f0f99e17 100644
--- a/core/io/stream_peer_tcp.h
+++ b/core/io/stream_peer_tcp.h
@@ -30,7 +30,6 @@
 
 #pragma once
 
-#include "core/io/ip.h"
 #include "core/io/ip_address.h"
 #include "core/io/stream_peer_socket.h"
 
diff --git a/core/io/stream_peer_tls.cpp b/core/io/stream_peer_tls.cpp
index 46b0f53195..3eb51c9b36 100644
--- a/core/io/stream_peer_tls.cpp
+++ b/core/io/stream_peer_tls.cpp
@@ -30,7 +30,6 @@
 
 #include "stream_peer_tls.h"
 
-#include "core/config/engine.h"
 #include "core/object/class_db.h"
 
 StreamPeerTLS *(*StreamPeerTLS::_create)(bool p_notify_postinitialize) = nullptr;
diff --git a/core/io/tcp_server.h b/core/io/tcp_server.h
index 4e3248a846..c1967b92e0 100644
--- a/core/io/tcp_server.h
+++ b/core/io/tcp_server.h
@@ -30,7 +30,7 @@
 
 #pragma once
 
-#include "core/io/ip.h"
+#include "core/io/ip_address.h"
 #include "core/io/socket_server.h"
 #include "core/io/stream_peer_tcp.h"
 
diff --git a/core/io/zip_io.h b/core/io/zip_io.h
index 82004d9ca3..f4c00f2c03 100644
--- a/core/io/zip_io.h
+++ b/core/io/zip_io.h
@@ -32,11 +32,9 @@
 
 #include "core/io/file_access.h"
 
-// Not directly used in this header, but assumed available in downstream users
-// like platform/*/export/export.cpp. Could be fixed, but probably better to have
-// thirdparty includes in as little headers as possible.
-#include "thirdparty/minizip/unzip.h"
-#include "thirdparty/minizip/zip.h"
+// This file serves as the Godot interface to minizip.
+#include "thirdparty/minizip/unzip.h" // IWYU pragma: export
+#include "thirdparty/minizip/zip.h" // IWYU pragma: export
 
 // Get the current file info and safely convert the full filepath to a String.
 int godot_unzip_get_current_file_info(unzFile p_zip_file, unz_file_info64 &r_file_info, String &r_filepath);
diff --git a/core/math/bvh.h b/core/math/bvh.h
index 5f0bf23f28..03a358f118 100644
--- a/core/math/bvh.h
+++ b/core/math/bvh.h
@@ -55,6 +55,8 @@
 #include "core/math/geometry_3d.h"
 #include "core/os/mutex.h"
 
+#include <climits> // INT_MAX
+
 #define BVHTREE_CLASS BVH_Tree<T, NUM_TREES, 2, MAX_ITEMS, USER_PAIR_TEST_FUNCTION, USER_CULL_TEST_FUNCTION, USE_PAIRS, BOUNDS, POINT>
 #define BVH_LOCKED_FUNCTION BVHLockedFunction _lock_guard(&_mutex, BVH_THREAD_SAFE &&_thread_safe);
 
diff --git a/core/math/bvh_abb.h b/core/math/bvh_abb.h
index b96ea0859a..cfb5ebd43e 100644
--- a/core/math/bvh_abb.h
+++ b/core/math/bvh_abb.h
@@ -32,6 +32,8 @@
 
 #include "core/math/aabb.h"
 
+#include <cfloat> // FLT_MAX
+
 // special optimized version of axis aligned bounding box
 template <typename BOUNDS = AABB, typename POINT = Vector3>
 struct BVH_ABB {
diff --git a/core/math/bvh_tree.h b/core/math/bvh_tree.h
index d33b8608ec..86daaab5ce 100644
--- a/core/math/bvh_tree.h
+++ b/core/math/bvh_tree.h
@@ -44,8 +44,6 @@
 #include "core/templates/local_vector.h"
 #include "core/templates/pooled_list.h"
 
-#include <climits>
-
 #define BVHABB_CLASS BVH_ABB<BOUNDS, POINT>
 
 // not sure if this is better yet so making optional
diff --git a/core/math/convex_hull.cpp b/core/math/convex_hull.cpp
index 926fb0d28a..e72515c99c 100644
--- a/core/math/convex_hull.cpp
+++ b/core/math/convex_hull.cpp
@@ -64,6 +64,8 @@ subject to the following restrictions:
 #include "core/templates/a_hash_map.h"
 #include "core/templates/paged_allocator.h"
 
+#include <cfloat> // FLT_MAX
+
 //#define DEBUG_CONVEX_HULL
 //#define SHOW_ITERATIONS
 
diff --git a/core/math/math_funcs.h b/core/math/math_funcs.h
index 971ecd5aea..43e4aac4eb 100644
--- a/core/math/math_funcs.h
+++ b/core/math/math_funcs.h
@@ -34,7 +34,6 @@
 #include "core/math/math_defs.h"
 #include "core/typedefs.h"
 
-#include <cfloat>
 #include <cmath>
 
 namespace Math {
diff --git a/core/math/random_pcg.h b/core/math/random_pcg.h
index bfcd3eeecc..618f3ebe76 100644
--- a/core/math/random_pcg.h
+++ b/core/math/random_pcg.h
@@ -34,6 +34,8 @@
 
 #include "thirdparty/misc/pcg.h"
 
+#include <cmath> // ldexp
+
 #if defined(__GNUC__)
 #define CLZ32(x) __builtin_clz(x)
 #elif defined(_MSC_VER)
@@ -122,14 +124,14 @@ public:
 		if (temp < CMP_EPSILON) {
 			temp += CMP_EPSILON; // To prevent generating of INF value in log function, resulting to return NaN value from this function.
 		}
-		return p_mean + p_deviation * (std::cos(Math::TAU * randd()) * std::sqrt(-2.0 * std::log(temp))); // Box-Muller transform.
+		return p_mean + p_deviation * (Math::cos(Math::TAU * randd()) * Math::sqrt(-2.0 * Math::log(temp))); // Box-Muller transform.
 	}
 	_FORCE_INLINE_ float randfn(float p_mean, float p_deviation) {
 		float temp = randf();
 		if (temp < CMP_EPSILON) {
 			temp += CMP_EPSILON; // To prevent generating of INF value in log function, resulting to return NaN value from this function.
 		}
-		return p_mean + p_deviation * (std::cos((float)Math::TAU * randf()) * std::sqrt(-2.0 * std::log(temp))); // Box-Muller transform.
+		return p_mean + p_deviation * (Math::cos((float)Math::TAU * randf()) * Math::sqrt(-2.0 * Math::log(temp))); // Box-Muller transform.
 	}
 
 	double random(double p_from, double p_to);
diff --git a/core/object/class_db.h b/core/object/class_db.h
index 2596ae85fd..24072b36de 100644
--- a/core/object/class_db.h
+++ b/core/object/class_db.h
@@ -55,7 +55,7 @@ inline constexpr bool is_class_enabled_v = is_class_enabled<T>::value;
 
 #define GD_IS_CLASS_ENABLED(m_class) is_class_enabled_v<m_class>
 
-#include "core/disabled_classes.gen.h"
+#include "core/disabled_classes.gen.h" // IWYU pragma: keep.
 
 #define DEFVAL(m_defval) (m_defval)
 #define DEFVAL_ARRAY DEFVAL(ClassDB::default_array_arg)
diff --git a/core/object/make_virtuals.py b/core/object/make_virtuals.py
index fe47477085..7ba4c31e70 100644
--- a/core/object/make_virtuals.py
+++ b/core/object/make_virtuals.py
@@ -196,10 +196,12 @@ def run(target, source, env):
     txt = """/* THIS FILE IS GENERATED DO NOT EDIT */
 #pragma once
 
+// IWYU pragma: begin_keep
 #include "core/object/script_instance.h"
 #include "core/variant/method_ptrcall.h"
 #include "core/variant/variant_caster.h"
 #include "core/variant/variant_internal.h"
+// IWYU pragma: end_keep
 
 inline constexpr uintptr_t _INVALID_GDVIRTUAL_FUNC_ADDR = static_cast<uintptr_t>(-1);
 
diff --git a/core/object/message_queue.cpp b/core/object/message_queue.cpp
index f5afc6f17e..5b97eb5f62 100644
--- a/core/object/message_queue.cpp
+++ b/core/object/message_queue.cpp
@@ -31,8 +31,6 @@
 #include "message_queue.h"
 
 #include "core/config/project_settings.h"
-#include "core/object/class_db.h"
-#include "core/object/script_language.h"
 
 #include <cstdio>
 
diff --git a/core/object/object.h b/core/object/object.h
index aaf33f9c86..c6877981b0 100644
--- a/core/object/object.h
+++ b/core/object/object.h
@@ -33,8 +33,8 @@
 #include "core/extension/gdextension_interface.gen.h"
 #include "core/object/gdtype.h"
 #include "core/object/object_id.h"
+#include "core/os/mutex.h"
 #include "core/os/spin_lock.h"
-#include "core/os/thread_safe.h"
 #include "core/templates/hash_map.h"
 #include "core/templates/hash_set.h"
 #include "core/templates/list.h"
diff --git a/core/object/ref_counted.cpp b/core/object/ref_counted.cpp
index a6834b1312..5980adfbec 100644
--- a/core/object/ref_counted.cpp
+++ b/core/object/ref_counted.cpp
@@ -31,7 +31,7 @@
 #include "ref_counted.h"
 
 #include "core/object/class_db.h"
-#include "core/object/script_language.h"
+#include "core/object/script_instance.h"
 
 bool RefCounted::init_ref() {
 	if (reference()) {
diff --git a/core/object/script_language.cpp b/core/object/script_language.cpp
index 275a95ad83..a8ee34a8f2 100644
--- a/core/object/script_language.cpp
+++ b/core/object/script_language.cpp
@@ -38,7 +38,6 @@
 #include "core/io/resource_loader.h"
 #include "core/object/callable_mp.h"
 #include "core/object/class_db.h"
-#include "core/os/os.h"
 #include "core/templates/sort_array.h"
 
 ScriptLanguage *ScriptServer::_languages[MAX_LANGUAGES];
diff --git a/core/object/worker_thread_pool.h b/core/object/worker_thread_pool.h
index d774da3ac5..808be67a26 100644
--- a/core/object/worker_thread_pool.h
+++ b/core/object/worker_thread_pool.h
@@ -37,7 +37,6 @@
 #include "core/os/thread.h"
 #include "core/templates/local_vector.h"
 #include "core/templates/paged_allocator.h"
-#include "core/templates/rid.h"
 #include "core/templates/safe_refcount.h"
 #include "core/templates/self_list.h"
 #include "core/variant/callable.h"
diff --git a/core/os/thread.cpp b/core/os/thread.cpp
index 4b0390ce7f..860f2218e5 100644
--- a/core/os/thread.cpp
+++ b/core/os/thread.cpp
@@ -28,7 +28,7 @@
 /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
 /**************************************************************************/
 
-#include "platform_config.h"
+#include "platform_config.h" // IWYU pragma: keep. Can override the implementation.
 
 #ifndef PLATFORM_THREAD_OVERRIDE // See details in thread.h.
 
diff --git a/core/os/thread.h b/core/os/thread.h
index 4e4a27ecc7..216433997a 100644
--- a/core/os/thread.h
+++ b/core/os/thread.h
@@ -30,7 +30,7 @@
 
 #pragma once
 
-#include "platform_config.h"
+#include "platform_config.h" // IWYU pragma: keep. Can override the implementation.
 
 // Define PLATFORM_THREAD_OVERRIDE in your platform's `platform_config.h`
 // to use a custom Thread implementation defined in `platform/[your_platform]/platform_thread.h`.
diff --git a/core/profiling/profiling.h b/core/profiling/profiling.h
index 4928fb8a8d..9dea94043f 100644
--- a/core/profiling/profiling.h
+++ b/core/profiling/profiling.h
@@ -30,7 +30,7 @@
 
 #pragma once
 
-#include "profiling.gen.h"
+#include "profiling.gen.h" // IWYU pragma: keep.
 
 // This header provides profiling primitives (implemented as macros) for various backends.
 // See the "No profiling" branch at the bottom for a short description of the functions.
diff --git a/core/string/ustring.cpp b/core/string/ustring.cpp
index 742a90d2a4..dfbc07b8b3 100644
--- a/core/string/ustring.cpp
+++ b/core/string/ustring.cpp
@@ -39,7 +39,6 @@ STATIC_ASSERT_INCOMPLETE_TYPE(class, Object);
 #include "core/math/color.h"
 #include "core/math/math_funcs.h"
 #include "core/object/object.h"
-#include "core/os/memory.h"
 #include "core/os/os.h"
 #include "core/string/print_string.h"
 #include "core/string/string_name.h"
diff --git a/core/templates/cowdata.h b/core/templates/cowdata.h
index 9be5aa32f8..f2d6e5459a 100644
--- a/core/templates/cowdata.h
+++ b/core/templates/cowdata.h
@@ -32,7 +32,7 @@
 
 #include "core/error/error_macros.h"
 #include "core/os/memory.h"
-#include "core/string/print_string.h"
+#include "core/string/print_string.h" // IWYU pragma: keep. `WARN_VERBOSE` macro.
 #include "core/templates/safe_refcount.h"
 #include "core/templates/span.h"
 
diff --git a/core/templates/hash_map.h b/core/templates/hash_map.h
index 3dbcae703f..62d6eb89b4 100644
--- a/core/templates/hash_map.h
+++ b/core/templates/hash_map.h
@@ -31,7 +31,7 @@
 #pragma once
 
 #include "core/os/memory.h"
-#include "core/string/print_string.h"
+#include "core/string/print_string.h" // IWYU pragma: keep. `WARN_VERBOSE` macro.
 #include "core/templates/hashfuncs.h"
 #include "core/templates/pair.h"
 #include "core/templates/sort_list.h"
diff --git a/core/templates/hash_set.h b/core/templates/hash_set.h
index f266322052..03bbce6cb3 100644
--- a/core/templates/hash_set.h
+++ b/core/templates/hash_set.h
@@ -31,7 +31,7 @@
 #pragma once
 
 #include "core/os/memory.h"
-#include "core/string/print_string.h"
+#include "core/string/print_string.h" // IWYU pragma: keep. `WARN_VERBOSE` macro.
 #include "core/templates/hashfuncs.h"
 
 /**
diff --git a/core/templates/local_vector.h b/core/templates/local_vector.h
index bf6fdc072a..13aea6fded 100644
--- a/core/templates/local_vector.h
+++ b/core/templates/local_vector.h
@@ -32,7 +32,7 @@
 
 #include "core/error/error_macros.h"
 #include "core/os/memory.h"
-#include "core/string/print_string.h"
+#include "core/string/print_string.h" // IWYU pragma: keep. `WARN_VERBOSE` macro.
 #include "core/templates/sort_array.h"
 #include "core/templates/vector.h"
 
diff --git a/core/variant/dictionary.cpp b/core/variant/dictionary.cpp
index b9ab03249a..9ca4ba2a56 100644
--- a/core/variant/dictionary.cpp
+++ b/core/variant/dictionary.cpp
@@ -38,10 +38,6 @@ STATIC_ASSERT_INCOMPLETE_TYPE(class, String);
 #include "core/templates/safe_refcount.h"
 #include "core/variant/container_type_validate.h"
 #include "core/variant/variant.h"
-// required in this order by VariantInternal, do not remove this comment.
-#include "core/object/class_db.h"
-#include "core/object/object.h"
-#include "core/variant/type_info.h"
 #include "core/variant/variant_internal.h"
 
 struct DictionaryPrivate {
diff --git a/core/variant/variant.h b/core/variant/variant.h
index 4bc236d557..ed7d195ff9 100644
--- a/core/variant/variant.h
+++ b/core/variant/variant.h
@@ -30,7 +30,7 @@
 
 #pragma once
 
-#include "core/core_string_names.h"
+#include "core/core_string_names.h" // IWYU pragma: export. Make available everywhere.
 #include "core/error/error_macros.h"
 #include "core/io/ip_address.h"
 #include "core/math/aabb.h"
diff --git a/core/variant/variant_call.cpp b/core/variant/variant_call.cpp
index 4c7994b86e..057c24e6de 100644
--- a/core/variant/variant_call.cpp
+++ b/core/variant/variant_call.cpp
@@ -30,14 +30,15 @@
 
 #include "variant.h"
 
-#include "core/crypto/crypto_core.h"
 #include "core/debugger/engine_debugger.h"
 #include "core/io/compression.h"
 #include "core/io/marshalls.h"
-#include "core/object/class_db.h"
 #include "core/os/os.h"
 #include "core/templates/a_hash_map.h"
 #include "core/templates/local_vector.h"
+#include "core/variant/binder_common.h"
+#include "core/variant/method_ptrcall.h"
+#include "core/variant/variant_internal.h"
 
 typedef void (*VariantFunc)(Variant &r_ret, Variant &p_self, const Variant **p_args);
 typedef void (*VariantConstructFunc)(Variant &r_ret, const Variant **p_args);
diff --git a/core/variant/variant_construct.h b/core/variant/variant_construct.h
index 48391488f3..2eefc8627d 100644
--- a/core/variant/variant_construct.h
+++ b/core/variant/variant_construct.h
@@ -32,13 +32,8 @@
 
 #include "variant.h"
 
-#include "core/crypto/crypto_core.h"
-#include "core/debugger/engine_debugger.h"
-#include "core/io/compression.h"
 #include "core/templates/a_hash_map.h"
-#include "core/templates/local_vector.h"
 #include "core/variant/binder_common.h"
-#include "core/variant/native_ptr.h"
 #include "core/variant/variant_internal.h"
 
 template <typename T>
diff --git a/core/variant/variant_op.h b/core/variant/variant_op.h
index 3ddea025d6..de1190f574 100644
--- a/core/variant/variant_op.h
+++ b/core/variant/variant_op.h
@@ -32,8 +32,9 @@
 
 #include "variant.h"
 
-#include "core/debugger/engine_debugger.h"
-#include "core/variant/native_ptr.h"
+#include "core/variant/method_ptrcall.h"
+#include "core/variant/type_info.h"
+#include "core/variant/variant_internal.h"
 
 template <typename Evaluator>
 class CommonEvaluate {
diff --git a/core/variant/variant_setget.cpp b/core/variant/variant_setget.cpp
index ec9a25cdae..91f92dda59 100644
--- a/core/variant/variant_setget.cpp
+++ b/core/variant/variant_setget.cpp
@@ -29,9 +29,10 @@
 /**************************************************************************/
 
 #include "variant_setget.h"
-#include "variant_callable.h"
 
+#include "core/debugger/engine_debugger.h"
 #include "core/io/resource.h"
+#include "core/variant/variant_callable.h"
 
 struct VariantSetterGetterInfo {
 	void (*setter)(Variant *base, const Variant *value, bool &valid);
diff --git a/core/variant/variant_setget.h b/core/variant/variant_setget.h
index c8176c2fff..1f56d8d591 100644
--- a/core/variant/variant_setget.h
+++ b/core/variant/variant_setget.h
@@ -32,8 +32,7 @@
 
 #include "variant.h"
 
-#include "core/debugger/engine_debugger.h"
-#include "core/variant/native_ptr.h"
+#include "core/variant/method_ptrcall.h"
 #include "core/variant/variant_internal.h"
 
 /**** NAMED SETTERS AND GETTERS ****/
diff --git a/core/variant/variant_utility.cpp b/core/variant/variant_utility.cpp
index 29893fccab..5f048ed456 100644
--- a/core/variant/variant_utility.cpp
+++ b/core/variant/variant_utility.cpp
@@ -32,7 +32,6 @@
 
 #include "core/io/marshalls.h"
 #include "core/object/ref_counted.h"
-#include "core/object/script_language.h"
 #include "core/os/os.h"
 #include "core/templates/a_hash_map.h"
 #include "core/templates/rid.h"
diff --git a/editor/animation/animation_track_editor.h b/editor/animation/animation_track_editor.h
index 7425d6a3ef..ff8a7656e1 100644
--- a/editor/animation/animation_track_editor.h
+++ b/editor/animation/animation_track_editor.h
@@ -41,6 +41,8 @@
 #include "scene/gui/tree.h"
 #include "scene/resources/animation.h"
 
+#include <cfloat> // FLT_MAX
+
 class AnimationMarkerEdit;
 class AnimationTrackEditor;
 class AnimationTrackEdit;
diff --git a/editor/doc/doc_tools.cpp b/editor/doc/doc_tools.cpp
index 63fe9bd57c..ae8688fb00 100644
--- a/editor/doc/doc_tools.cpp
+++ b/editor/doc/doc_tools.cpp
@@ -37,6 +37,7 @@
 #include "core/io/compression.h"
 #include "core/io/dir_access.h"
 #include "core/io/resource_importer.h"
+#include "core/io/xml_parser.h"
 #include "core/object/class_db.h"
 #include "core/object/script_language.h"
 #include "core/string/translation_server.h"
diff --git a/editor/doc/doc_tools.h b/editor/doc/doc_tools.h
index b66ce59c6b..f11133c65c 100644
--- a/editor/doc/doc_tools.h
+++ b/editor/doc/doc_tools.h
@@ -33,6 +33,8 @@
 #include "core/doc_data.h"
 #include "core/templates/rb_set.h"
 
+class XMLParser;
+
 class DocTools {
 public:
 	String version;
diff --git a/main/main.cpp b/main/main.cpp
index 98c75fadbf..3c99ae8504 100644
--- a/main/main.cpp
+++ b/main/main.cpp
@@ -57,6 +57,7 @@
 #include "core/profiling/profiling.h"
 #include "core/register_core_types.h"
 #include "core/string/translation_server.h"
+#include "core/variant/variant_parser.h"
 #include "core/version.h"
 #include "drivers/register_driver_types.h"
 #include "main/app_icon.gen.h"
diff --git a/modules/csg/csg_shape.cpp b/modules/csg/csg_shape.cpp
index 8119666f44..028279d53c 100644
--- a/modules/csg/csg_shape.cpp
+++ b/modules/csg/csg_shape.cpp
@@ -49,6 +49,8 @@
 
 #include <manifold/manifold.h>
 
+#include <cfloat> // FLT_EPSILON
+
 #ifndef NAVIGATION_3D_DISABLED
 Callable CSGShape3D::_navmesh_source_geometry_parsing_callback;
 RID CSGShape3D::_navmesh_source_geometry_parser;
diff --git a/modules/gltf/editor/editor_import_blend_runner.cpp b/modules/gltf/editor/editor_import_blend_runner.cpp
index b11800c4eb..cbfd099e0f 100644
--- a/modules/gltf/editor/editor_import_blend_runner.cpp
+++ b/modules/gltf/editor/editor_import_blend_runner.cpp
@@ -31,6 +31,7 @@
 #include "editor_import_blend_runner.h"
 
 #include "core/io/http_client.h"
+#include "core/io/xml_parser.h"
 #include "core/object/callable_mp.h"
 #include "core/os/os.h"
 #include "editor/editor_node.h"
diff --git a/modules/gltf/extensions/gltf_light.cpp b/modules/gltf/extensions/gltf_light.cpp
index 64aa7f2260..830b62293c 100644
--- a/modules/gltf/extensions/gltf_light.cpp
+++ b/modules/gltf/extensions/gltf_light.cpp
@@ -35,6 +35,8 @@
 #include "core/object/class_db.h"
 #include "scene/3d/light_3d.h"
 
+#include <cfloat> // FLT_MAX
+
 void GLTFLight::_bind_methods() {
 	ClassDB::bind_static_method("GLTFLight", D_METHOD("from_node", "light_node"), &GLTFLight::from_node);
 	ClassDB::bind_method(D_METHOD("to_node"), &GLTFLight::to_node);
diff --git a/modules/godot_physics_3d/godot_body_pair_3d.cpp b/modules/godot_physics_3d/godot_body_pair_3d.cpp
index bc69ef1dcf..1bbd1289df 100644
--- a/modules/godot_physics_3d/godot_body_pair_3d.cpp
+++ b/modules/godot_physics_3d/godot_body_pair_3d.cpp
@@ -33,6 +33,8 @@
 #include "godot_collision_solver_3d.h"
 #include "godot_space_3d.h"
 
+#include <cfloat> // FLT_MAX
+
 #define MIN_VELOCITY 0.0001
 #define MAX_BIAS_ROTATION (Math::PI / 8)
 
diff --git a/modules/navigation_2d/nav_utils_2d.h b/modules/navigation_2d/nav_utils_2d.h
index 4c33c16669..c45ef2b0ae 100644
--- a/modules/navigation_2d/nav_utils_2d.h
+++ b/modules/navigation_2d/nav_utils_2d.h
@@ -37,6 +37,8 @@
 #include "core/templates/local_vector.h"
 #include "servers/navigation_2d/navigation_constants_2d.h"
 
+#include <cfloat> // FLT_MAX
+
 class NavBaseIteration2D;
 
 namespace Nav2D {
diff --git a/modules/navigation_3d/nav_utils_3d.h b/modules/navigation_3d/nav_utils_3d.h
index d18fb92c58..5b8b4aff87 100644
--- a/modules/navigation_3d/nav_utils_3d.h
+++ b/modules/navigation_3d/nav_utils_3d.h
@@ -37,6 +37,8 @@
 #include "core/templates/local_vector.h"
 #include "servers/navigation_3d/navigation_constants_3d.h"
 
+#include <cfloat> // FLT_MAX
+
 class NavBaseIteration3D;
 
 namespace Nav3D {
diff --git a/modules/noise/noise.cpp b/modules/noise/noise.cpp
index 55d936159e..5c5f51848d 100644
--- a/modules/noise/noise.cpp
+++ b/modules/noise/noise.cpp
@@ -32,6 +32,8 @@
 
 #include "core/object/class_db.h"
 
+#include <cfloat> // FLT_MAX
+
 Vector<Ref<Image>> Noise::_get_seamless_image(int p_width, int p_height, int p_depth, bool p_invert, bool p_in_3d_space, real_t p_blend_skirt, bool p_normalize) const {
 	ERR_FAIL_COND_V(p_width <= 0 || p_height <= 0 || p_depth <= 0, Vector<Ref<Image>>());
 
diff --git a/modules/xatlas_unwrap/register_types.cpp b/modules/xatlas_unwrap/register_types.cpp
index e5da9b3a4f..60d6bb8931 100644
--- a/modules/xatlas_unwrap/register_types.cpp
+++ b/modules/xatlas_unwrap/register_types.cpp
@@ -31,9 +31,13 @@
 #include "register_types.h"
 
 #include "core/crypto/crypto_core.h"
+#include "core/error/error_macros.h"
+#include "core/os/memory.h"
 
 #include <xatlas.h>
 
+#include <cstring>
+
 extern bool (*array_mesh_lightmap_unwrap_callback)(float p_texel_size, const float *p_vertices, const float *p_normals, int p_vertex_count, const int *p_indices, int p_index_count, const uint8_t *p_cache_data, bool *r_use_cache, uint8_t **r_mesh_cache, int *r_mesh_cache_size, float **r_uv, int **r_vertex, int *r_vertex_count, int **r_index, int *r_index_count, int *r_size_hint_x, int *r_size_hint_y);
 
 bool xatlas_mesh_lightmap_unwrap_callback(float p_texel_size, const float *p_vertices, const float *p_normals, int p_vertex_count, const int *p_indices, int p_index_count, const uint8_t *p_cache_data, bool *r_use_cache, uint8_t **r_mesh_cache, int *r_mesh_cache_size, float **r_uv, int **r_vertex, int *r_vertex_count, int **r_index, int *r_index_count, int *r_size_hint_x, int *r_size_hint_y) {
diff --git a/platform/linuxbsd/x11/display_server_x11.h b/platform/linuxbsd/x11/display_server_x11.h
index 289c62a129..38b4a7a720 100644
--- a/platform/linuxbsd/x11/display_server_x11.h
+++ b/platform/linuxbsd/x11/display_server_x11.h
@@ -36,6 +36,7 @@
 #include "core/os/mutex.h"
 #include "core/os/process_id.h"
 #include "core/os/thread.h"
+#include "core/os/thread_safe.h"
 #include "core/templates/local_vector.h"
 #include "servers/display/display_server.h"
 
diff --git a/platform/macos/display_server_macos_base.h b/platform/macos/display_server_macos_base.h
index 2d53766129..de9ae92290 100644
--- a/platform/macos/display_server_macos_base.h
+++ b/platform/macos/display_server_macos_base.h
@@ -30,6 +30,7 @@
 
 #pragma once
 
+#include "core/os/thread_safe.h"
 #include "servers/display/display_server.h"
 
 #define FontVariation __FontVariation
diff --git a/scene/3d/mesh_instance_3d.cpp b/scene/3d/mesh_instance_3d.cpp
index e3141d6c88..6648a9ec4b 100644
--- a/scene/3d/mesh_instance_3d.cpp
+++ b/scene/3d/mesh_instance_3d.cpp
@@ -47,7 +47,11 @@
 #include "scene/resources/navigation_mesh.h"
 #include "servers/navigation_3d/navigation_server_3d.h"
 #include "servers/rendering/rendering_server.h"
+#endif // NAVIGATION_3D_DISABLED
 
+#include <cfloat> // FLT_EPSILON
+
+#ifndef NAVIGATION_3D_DISABLED
 Callable MeshInstance3D::_navmesh_source_geometry_parsing_callback;
 RID MeshInstance3D::_navmesh_source_geometry_parser;
 #endif // NAVIGATION_3D_DISABLED
diff --git a/scene/gui/graph_edit_arranger.cpp b/scene/gui/graph_edit_arranger.cpp
index 1c21ba978a..7cd0ff7ddf 100644
--- a/scene/gui/graph_edit_arranger.cpp
+++ b/scene/gui/graph_edit_arranger.cpp
@@ -32,6 +32,8 @@
 
 #include "scene/gui/graph_edit.h"
 
+#include <cfloat> // FLT_MIN, FLT_MAX
+
 void GraphEditArranger::arrange_nodes() {
 	ERR_FAIL_NULL(graph_edit);
 
diff --git a/scene/gui/tab_bar.cpp b/scene/gui/tab_bar.cpp
index e668452151..258bfb1f0d 100644
--- a/scene/gui/tab_bar.cpp
+++ b/scene/gui/tab_bar.cpp
@@ -41,6 +41,8 @@
 #include "scene/theme/theme_db.h"
 #include "servers/display/accessibility_server.h"
 
+#include <cfloat> // FLT_MAX
+
 static inline Color _select_color(const Color &p_override_color, const Color &p_default_color) {
 	return p_override_color.a > 0 ? p_override_color : p_default_color;
 }
diff --git a/scene/main/node.h b/scene/main/node.h
index 80d7f594dd..111ead3fa6 100644
--- a/scene/main/node.h
+++ b/scene/main/node.h
@@ -34,6 +34,7 @@
 #include "core/object/gdvirtual.gen.h"
 #include "core/object/object.h"
 #include "core/object/ref_counted.h"
+#include "core/os/thread_safe.h"
 #include "core/templates/iterable.h"
 #include "scene/scene_string_names.h" // IWYU pragma: export. Make available to all Nodes.
 
diff --git a/scene/resources/3d/height_map_shape_3d.cpp b/scene/resources/3d/height_map_shape_3d.cpp
index 494cea051c..e7a82bd31b 100644
--- a/scene/resources/3d/height_map_shape_3d.cpp
+++ b/scene/resources/3d/height_map_shape_3d.cpp
@@ -35,6 +35,8 @@
 #include "scene/resources/mesh.h"
 #include "servers/physics_3d/physics_server_3d.h"
 
+#include <cfloat> // FLT_MAX
+
 Vector<Vector3> HeightMapShape3D::get_debug_mesh_lines() const {
 	Vector<Vector3> points;
 
diff --git a/scene/resources/3d/importer_mesh.cpp b/scene/resources/3d/importer_mesh.cpp
index 04a798db11..df98b50772 100644
--- a/scene/resources/3d/importer_mesh.cpp
+++ b/scene/resources/3d/importer_mesh.cpp
@@ -39,6 +39,8 @@
 #include "core/math/convex_hull.h"
 #endif // PHYSICS_3D_DISABLED
 
+#include <cfloat> // FLT_EPSILON
+
 Ref<ImporterMesh> ImporterMesh::merge_importer_meshes(const TypedArray<ImporterMesh> &p_importer_meshes, const TypedArray<Transform3D> &p_relative_transforms, bool p_deduplicate_surfaces) {
 	// Setup and safety checks.
 	const int mesh_count = p_importer_meshes.size();
diff --git a/scene/resources/curve.cpp b/scene/resources/curve.cpp
index c21b0945b8..8bb8b2b868 100644
--- a/scene/resources/curve.cpp
+++ b/scene/resources/curve.cpp
@@ -33,6 +33,8 @@
 #include "core/math/math_funcs.h"
 #include "core/object/class_db.h"
 
+#include <cfloat> // FLT_EPSILON
+
 const char *Curve::SIGNAL_RANGE_CHANGED = "range_changed";
 const char *Curve::SIGNAL_DOMAIN_CHANGED = "domain_changed";
 
diff --git a/scene/resources/style_box_flat.cpp b/scene/resources/style_box_flat.cpp
index fc4373f562..24d784d922 100644
--- a/scene/resources/style_box_flat.cpp
+++ b/scene/resources/style_box_flat.cpp
@@ -35,6 +35,8 @@
 #include "servers/rendering/rendering_server.h"
 #include "servers/text/text_server.h"
 
+#include <cfloat> // FLT_EPSILON
+
 float StyleBoxFlat::get_style_margin(Side p_side) const {
 	ERR_FAIL_INDEX_V((int)p_side, 4, 0.0);
 	return border_width[p_side];
diff --git a/scene/resources/text_paragraph.h b/scene/resources/text_paragraph.h
index 5a5a2c6d2e..21561dcb78 100644
--- a/scene/resources/text_paragraph.h
+++ b/scene/resources/text_paragraph.h
@@ -30,6 +30,7 @@
 
 #pragma once
 
+#include "core/os/thread_safe.h"
 #include "core/templates/local_vector.h"
 #include "scene/resources/font.h"
 #include "servers/text/text_server.h"
diff --git a/servers/rendering/renderer_scene_occlusion_cull.h b/servers/rendering/renderer_scene_occlusion_cull.h
index 21585048b0..675a80f486 100644
--- a/servers/rendering/renderer_scene_occlusion_cull.h
+++ b/servers/rendering/renderer_scene_occlusion_cull.h
@@ -35,6 +35,8 @@
 #include "core/templates/local_vector.h"
 #include "servers/rendering/rendering_server_enums.h"
 
+#include <cfloat> // FLT_MIN, FLT_MAX
+
 class RendererSceneOcclusionCull {
 protected:
 	static RendererSceneOcclusionCull *singleton;
diff --git a/tests/core/io/test_json.cpp b/tests/core/io/test_json.cpp
index 6f753c1a21..7eb28d98f4 100644
--- a/tests/core/io/test_json.cpp
+++ b/tests/core/io/test_json.cpp
@@ -35,6 +35,8 @@ TEST_FORCE_LINK(test_json)
 #include "core/io/json.h"
 #include "core/variant/typed_array.h"
 
+#include <cfloat> // DBL_MAX
+
 namespace TestJSON {
 
 TEST_CASE("[JSON] Stringify single data types") {