diff --git a/compat/BUILD.gn b/compat/BUILD.gn
index 2436b84..a38724c 100644
--- a/compat/BUILD.gn
+++ b/compat/BUILD.gn
@@ -57,7 +57,7 @@
     # static_library.
     group(target_name) {
       forward_variables_from(invoker, "*")
-      not_needed(["configs"])
+      not_needed([ "configs" ])
     }
   } else {
     static_library(target_name) {
@@ -71,7 +71,8 @@
 
   if (crashpad_is_mac || crashpad_is_ios) {
     sources += [
-      "mac/AvailabilityMacros.h",
+      "mac/Availability.h",
+      "mac/AvailabilityVersions.h",
       "mac/kern/exc_resource.h",
       "mac/mach-o/loader.h",
       "mac/mach/i386/thread_state.h",
diff --git a/compat/compat.gyp b/compat/compat.gyp
index b99d690..1c2eeaf 100644
--- a/compat/compat.gyp
+++ b/compat/compat.gyp
@@ -38,7 +38,8 @@
         'linux/signal.h',
         'linux/sys/ptrace.h',
         'linux/sys/user.h',
-        'mac/AvailabilityMacros.h',
+        'mac/Availability.h',
+        'mac/AvailabilityVersions.h',
         'mac/kern/exc_resource.h',
         'mac/mach/i386/thread_state.h',
         'mac/mach/mach.h',
diff --git a/compat/mac/Availability.h b/compat/mac/Availability.h
new file mode 100644
index 0000000..b8f8f2d
--- /dev/null
+++ b/compat/mac/Availability.h
@@ -0,0 +1,28 @@
+// Copyright 2020 The Crashpad Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef CRASHPAD_COMPAT_MAC_AVAILABILITY_H_
+#define CRASHPAD_COMPAT_MAC_AVAILABILITY_H_
+
+// Until the 10.15 SDK, the contents of <AvailabilityVersions.h> was in-line in
+// <Availability.h>, but since then, it was broken out into its own header.
+// This compat version of <Availability.h> allows these macros to always appear
+// to be provided by the new header, <AvailabilityVersions.h>, even when an
+// older SDK is in use.
+
+#include_next <Availability.h>
+
+#include <AvailabilityVersions.h>
+
+#endif  // CRASHPAD_COMPAT_MAC_AVAILABILITY_H_
diff --git a/compat/mac/AvailabilityMacros.h b/compat/mac/AvailabilityMacros.h
deleted file mode 100644
index a83d2a4..0000000
--- a/compat/mac/AvailabilityMacros.h
+++ /dev/null
@@ -1,74 +0,0 @@
-// Copyright 2014 The Crashpad Authors. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef CRASHPAD_COMPAT_MAC_AVAILABILITYMACROS_H_
-#define CRASHPAD_COMPAT_MAC_AVAILABILITYMACROS_H_
-
-#include_next <AvailabilityMacros.h>
-
-// 10.7 SDK
-
-#ifndef MAC_OS_X_VERSION_10_7
-#define MAC_OS_X_VERSION_10_7 1070
-#endif
-
-// 10.8 SDK
-
-#ifndef MAC_OS_X_VERSION_10_8
-#define MAC_OS_X_VERSION_10_8 1080
-#endif
-
-// 10.9 SDK
-
-#ifndef MAC_OS_X_VERSION_10_9
-#define MAC_OS_X_VERSION_10_9 1090
-#endif
-
-// 10.10 SDK
-
-#ifndef MAC_OS_X_VERSION_10_10
-#define MAC_OS_X_VERSION_10_10 101000
-#endif
-
-// 10.11 SDK
-
-#ifndef MAC_OS_X_VERSION_10_11
-#define MAC_OS_X_VERSION_10_11 101100
-#endif
-
-// 10.12 SDK
-
-#ifndef MAC_OS_X_VERSION_10_12
-#define MAC_OS_X_VERSION_10_12 101200
-#endif
-
-// 10.13 SDK
-
-#ifndef MAC_OS_X_VERSION_10_13
-#define MAC_OS_X_VERSION_10_13 101300
-#endif
-
-// 10.14 SDK
-
-#ifndef MAC_OS_X_VERSION_10_14
-#define MAC_OS_X_VERSION_10_14 101400
-#endif
-
-// 10.15 SDK
-
-#ifndef MAC_OS_X_VERSION_10_15
-#define MAC_OS_X_VERSION_10_15 101500
-#endif
-
-#endif  // CRASHPAD_COMPAT_MAC_AVAILABILITYMACROS_H_
diff --git a/compat/mac/AvailabilityVersions.h b/compat/mac/AvailabilityVersions.h
new file mode 100644
index 0000000..8e932c5
--- /dev/null
+++ b/compat/mac/AvailabilityVersions.h
@@ -0,0 +1,86 @@
+// Copyright 2020 The Crashpad Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef CRASHPAD_COMPAT_MAC_AVAILABILITYVERSIONS_H_
+#define CRASHPAD_COMPAT_MAC_AVAILABILITYVERSIONS_H_
+
+#if __has_include_next(<AvailabilityVersions.h>)
+#include_next <AvailabilityVersions.h>
+#endif
+
+// 10.7 SDK
+
+#ifndef __MAC_10_7
+#define __MAC_10_7 1070
+#endif
+
+// 10.8 SDK
+
+#ifndef __MAC_10_8
+#define __MAC_10_8 1080
+#endif
+
+// 10.9 SDK
+
+#ifndef __MAC_10_9
+#define __MAC_10_9 1090
+#endif
+
+// 10.10 SDK
+
+#ifndef __MAC_10_10
+#define __MAC_10_10 101000
+#endif
+
+// 10.11 SDK
+
+#ifndef __MAC_10_11
+#define __MAC_10_11 101100
+#endif
+
+// 10.12 SDK
+
+#ifndef __MAC_10_12
+#define __MAC_10_12 101200
+#endif
+
+// 10.13 SDK
+
+#ifndef __MAC_10_13
+#define __MAC_10_13 101300
+#endif
+
+// 10.14 SDK
+
+#ifndef __MAC_10_14
+#define __MAC_10_14 101400
+#endif
+
+// 10.15 SDK
+
+#ifndef __MAC_10_15
+#define __MAC_10_15 101500
+#endif
+
+// 11.0 SDK
+
+#ifndef __MAC_10_16
+#define __MAC_10_16 101600
+#endif
+
+#ifndef __MAC_11_0
+#define __MAC_11_0 110000
+#endif
+
+#endif  // CRASHPAD_COMPAT_MAC_AVAILABILITYVERSIONS_H_
diff --git a/minidump/minidump_misc_info_writer.cc b/minidump/minidump_misc_info_writer.cc
index d2d8511..1343560 100644
--- a/minidump/minidump_misc_info_writer.cc
+++ b/minidump/minidump_misc_info_writer.cc
@@ -31,7 +31,7 @@
 #include "util/numeric/safe_assignment.h"
 
 #if defined(OS_APPLE)
-#include <AvailabilityMacros.h>
+#include <Availability.h>
 #elif defined(OS_ANDROID)
 #include <android/api-level.h>
 #endif
@@ -66,20 +66,19 @@
   return machine_description;
 }
 
-#if defined(OS_APPLE)
-// Converts the value of the MAC_OS_VERSION_MIN_REQUIRED or
-// MAC_OS_X_VERSION_MAX_ALLOWED macro from <AvailabilityMacros.h> to a number
+#if defined(OS_MAC)
+// Converts the value of the __MAC_OS_X_VERSION_MIN_REQUIRED or
+// __MAC_OS_X_VERSION_MAX_ALLOWED macro from <Availability.h> to a number
 // identifying the minor macOS version that it represents. For example, with an
-// argument of MAC_OS_X_VERSION_10_6, this function will return 6.
+// argument of __MAC_10_6, this function will return 6.
 int AvailabilityVersionToMacOSXMinorVersion(int availability) {
-  // Through MAC_OS_X_VERSION_10_9, the minor version is the tens digit.
+  // Through __MAC_10_9, the minor version is the tens digit.
   if (availability >= 1000 && availability <= 1099) {
     return (availability / 10) % 10;
   }
 
-  // After MAC_OS_X_VERSION_10_9, the older format was insufficient to represent
-  // versions. Since then, the minor version is the thousands and hundreds
-  // digits.
+  // After __MAC_10_9, the older format was insufficient to represent versions.
+  // Since then, the minor version is the thousands and hundreds digits.
   if (availability >= 100000 && availability <= 109999) {
     return (availability / 100) % 100;
   }
@@ -136,11 +135,11 @@
                                                       PACKAGE_VERSION,
                                                       kOS);
 
-#if defined(OS_APPLE)
+#if defined(OS_MAC)
   debug_build_string += base::StringPrintf(
       ",%d,%d",
-      AvailabilityVersionToMacOSXMinorVersion(MAC_OS_X_VERSION_MIN_REQUIRED),
-      AvailabilityVersionToMacOSXMinorVersion(MAC_OS_X_VERSION_MAX_ALLOWED));
+      AvailabilityVersionToMacOSXMinorVersion(__MAC_OS_X_VERSION_MIN_REQUIRED),
+      AvailabilityVersionToMacOSXMinorVersion(__MAC_OS_X_VERSION_MAX_ALLOWED));
 #elif defined(OS_ANDROID)
   debug_build_string += base::StringPrintf(",%d", __ANDROID_API__);
 #endif
diff --git a/snapshot/mac/mach_o_image_reader_test.cc b/snapshot/mac/mach_o_image_reader_test.cc
index 53826bf..f1f3b1d 100644
--- a/snapshot/mac/mach_o_image_reader_test.cc
+++ b/snapshot/mac/mach_o_image_reader_test.cc
@@ -14,7 +14,7 @@
 
 #include "snapshot/mac/mach_o_image_reader.h"
 
-#include <AvailabilityMacros.h>
+#include <Availability.h>
 #include <dlfcn.h>
 #include <mach-o/dyld.h>
 #include <mach-o/dyld_images.h>
@@ -606,7 +606,7 @@
     ASSERT_NO_FATAL_FAILURE(ExpectSymbolTable(mach_header, &image_reader));
   }
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_7
   // If dyld is new enough to record UUIDs, check the UUID of any module that
   // it says has one. Note that dyld doesn’t record UUIDs of anything that
   // loaded out of the shared cache, but it should at least have a UUID for the
diff --git a/snapshot/mac/process_reader_mac.cc b/snapshot/mac/process_reader_mac.cc
index ca2c1f7..fafa615 100644
--- a/snapshot/mac/process_reader_mac.cc
+++ b/snapshot/mac/process_reader_mac.cc
@@ -14,7 +14,7 @@
 
 #include "snapshot/mac/process_reader_mac.h"
 
-#include <AvailabilityMacros.h>
+#include <Availability.h>
 #include <mach-o/loader.h>
 #include <mach/mach_vm.h>
 
@@ -213,7 +213,7 @@
 // This may look for the module that matches the executable path in the same
 // data set that vmmap uses.
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_7
   // The task_dyld_info_data_t struct grew in 10.7, adding the format field.
   // Don’t check this field if it’s not present, which can happen when either
   // the SDK used at compile time or the kernel at run time are too old and
diff --git a/snapshot/mac/process_reader_mac_test.cc b/snapshot/mac/process_reader_mac_test.cc
index 2d64ff1..3233228 100644
--- a/snapshot/mac/process_reader_mac_test.cc
+++ b/snapshot/mac/process_reader_mac_test.cc
@@ -14,9 +14,9 @@
 
 #include "snapshot/mac/process_reader_mac.h"
 
-#include <AvailabilityMacros.h>
-#include <errno.h>
+#include <Availability.h>
 #include <OpenCL/opencl.h>
+#include <errno.h>
 #include <mach-o/dyld.h>
 #include <mach-o/dyld_images.h>
 #include <mach/mach.h>
@@ -569,12 +569,12 @@
     cl_int rv = clGetPlatformIDs(1, &platform_id, nullptr);
     ASSERT_EQ(rv, CL_SUCCESS) << "clGetPlatformIDs";
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_10 && \
-    MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_10
-// cl_device_id is really available in OpenCL.framework back to 10.5, but in
-// the 10.10 SDK and later, OpenCL.framework includes <OpenGL/CGLDevice.h>,
-// which has its own cl_device_id that was introduced in 10.10. That
-// triggers erroneous availability warnings.
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_10 && \
+    __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_10
+    // cl_device_id is really available in OpenCL.framework back to 10.5, but in
+    // the 10.10 SDK and later, OpenCL.framework includes <OpenGL/CGLDevice.h>,
+    // which has its own cl_device_id that was introduced in 10.10. That
+    // triggers erroneous availability warnings.
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wunguarded-availability"
 #define DISABLED_WUNGUARDED_AVAILABILITY
@@ -640,7 +640,7 @@
 // OpenCL kernels that run on the CPU do not result in cl_kernels images
 // appearing on that OS version.
 bool ExpectCLKernels() {
-#if MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_7
+#if __MAC_OS_X_VERSION_MIN_REQUIRED >= __MAC_10_7
   return true;
 #else
   return MacOSXMinorVersion() >= 7;
diff --git a/snapshot/mac/process_types_test.cc b/snapshot/mac/process_types_test.cc
index 0ad2869..5e5ebf1 100644
--- a/snapshot/mac/process_types_test.cc
+++ b/snapshot/mac/process_types_test.cc
@@ -14,7 +14,7 @@
 
 #include "snapshot/mac/process_types.h"
 
-#include <AvailabilityMacros.h>
+#include <Availability.h>
 #include <mach/mach.h>
 #include <string.h>
 
@@ -68,7 +68,7 @@
   if (self_image_infos->version >= 2) {
     EXPECT_TRUE(self_image_infos->libSystemInitialized);
   }
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_7
   if (self_image_infos->version >= 9) {
     EXPECT_EQ(self_image_infos->dyldAllImageInfosAddress, self_image_infos);
   }
@@ -90,7 +90,7 @@
 
   // This field is only present in the OS X 10.7 SDK (at build time) and kernel
   // (at run time).
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_7
   if (MacOSXMinorVersion() >= 7) {
 #if !defined(ARCH_CPU_64_BITS)
     EXPECT_EQ(dyld_info.all_image_info_format, TASK_DYLD_ALL_IMAGE_INFO_32);
@@ -103,15 +103,15 @@
   ProcessReaderMac process_reader;
   ASSERT_TRUE(process_reader.Initialize(mach_task_self()));
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_15
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_15
   constexpr uint32_t kDyldAllImageInfosVersionInSDK = 16;
-#elif MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_12
+#elif __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_12
   constexpr uint32_t kDyldAllImageInfosVersionInSDK = 15;
-#elif MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_9
+#elif __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_9
   constexpr uint32_t kDyldAllImageInfosVersionInSDK = 14;
-#elif MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+#elif __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_7
   constexpr uint32_t kDyldAllImageInfosVersionInSDK = 12;
-#elif MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_6
+#elif __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_6
   constexpr uint32_t kDyldAllImageInfosVersionInSDK = 7;
 #else
   constexpr uint32_t kDyldAllImageInfosVersionInSDK = 1;
@@ -126,11 +126,11 @@
   // test can only be performed if the run-time OS natively uses the same format
   // structure as the SDK.
   bool test_expected_size_for_version_matches_sdk_sizeof;
-#if MAC_OS_X_VERSION_MAX_ALLOWED == MAC_OS_X_VERSION_10_12
+#if __MAC_OS_X_VERSION_MAX_ALLOWED == __MAC_10_12
   test_expected_size_for_version_matches_sdk_sizeof =
       mac_os_x_minor_version == 12;
-#elif MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_13 && \
-    MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_15
+#elif __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_13 && \
+    __MAC_OS_X_VERSION_MAX_ALLOWED < __MAC_10_15
   test_expected_size_for_version_matches_sdk_sizeof =
       mac_os_x_minor_version >= 13 && mac_os_x_minor_version <= 14;
 #else
@@ -257,7 +257,7 @@
     EXPECT_EQ(proctype_image_infos.systemOrderFlag,
               implicit_cast<uint64_t>(self_image_infos->systemOrderFlag));
   }
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_7
   if (proctype_image_infos.version >= 8) {
     EXPECT_EQ(proctype_image_infos.uuidArrayCount,
               implicit_cast<uint64_t>(self_image_infos->uuidArrayCount));
@@ -299,7 +299,7 @@
               implicit_cast<uint64_t>(self_image_infos->sharedCacheSlide));
   }
 #endif
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_9
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_9
   if (proctype_image_infos.version >= 13) {
     EXPECT_EQ(memcmp(self_image_infos->sharedCacheUUID,
                      proctype_image_infos.sharedCacheUUID,
@@ -307,7 +307,7 @@
               0);
   }
 #endif
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_12
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_12
   if (proctype_image_infos.version >= 15) {
     EXPECT_EQ(proctype_image_infos.infoArrayChangeTimestamp,
               self_image_infos->infoArrayChangeTimestamp);
@@ -327,7 +327,7 @@
   }
 #endif
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_12
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_12
   // As dyld_all_image_infos has evolved over time, new fields were added to the
   // reserved region. process_types::dyld_all_image_infos declares a recent
   // version of the structure, but an older SDK may declare an older version
@@ -352,7 +352,7 @@
   }
 #endif
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_13
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_13
   if (proctype_image_infos.version >= 15 && mac_os_x_minor_version >= 13) {
     EXPECT_EQ(proctype_image_infos.compact_dyld_image_info_addr,
               self_image_infos->compact_dyld_image_info_addr);
@@ -361,7 +361,7 @@
   }
 #endif
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_15
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_15
   if (proctype_image_infos.version >= 16) {
     EXPECT_EQ(proctype_image_infos.platform, self_image_infos->platform);
   }
@@ -399,7 +399,7 @@
     }
   }
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_7
   if (proctype_image_infos.version >= 8) {
     std::vector<process_types::dyld_uuid_info> proctype_uuid_info_vector(
         proctype_image_infos.uuidArrayCount);
diff --git a/snapshot/mac/system_snapshot_mac.cc b/snapshot/mac/system_snapshot_mac.cc
index 62eb814..e3bfc1c 100644
--- a/snapshot/mac/system_snapshot_mac.cc
+++ b/snapshot/mac/system_snapshot_mac.cc
@@ -14,7 +14,7 @@
 
 #include "snapshot/mac/system_snapshot_mac.h"
 
-#include <AvailabilityMacros.h>
+#include <Availability.h>
 #include <stddef.h>
 #include <sys/sysctl.h>
 #include <sys/types.h>
@@ -364,7 +364,7 @@
       // xnu-6153.11.26/bsd/kern/kern_sysctl.c (10.14.4 and 10.14.5 xnu source
       // are not yet available). In newer production kernels, NX is always
       // enabled. See 10.15.0 xnu-6153.11.26/osfmk/x86_64/pmap.c nx_enabled.
-#if MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_14
+#if __MAC_OS_X_VERSION_MIN_REQUIRED >= __MAC_10_14
       const bool nx_always_enabled = true;
 #else  // DT >= 10.14
       base::ScopedClearLastError reset_errno;
diff --git a/test/mac/dyld.cc b/test/mac/dyld.cc
index fb2156e..ba1cb56 100644
--- a/test/mac/dyld.cc
+++ b/test/mac/dyld.cc
@@ -14,10 +14,10 @@
 
 #include "test/mac/dyld.h"
 
-#include <AvailabilityMacros.h>
+#include <Availability.h>
 #include <dlfcn.h>
-#include <mach/mach.h>
 #include <mach-o/dyld.h>
+#include <mach/mach.h>
 #include <stdint.h>
 
 #include "base/logging.h"
@@ -25,7 +25,7 @@
 #include "test/scoped_module_handle.h"
 #include "util/numeric/safe_assignment.h"
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_13
+#if __MAC_OS_X_VERSION_MAX_ALLOWED < __MAC_10_13
 extern "C" {
 
 // A non-public dyld API, declared in 10.12.4
@@ -41,14 +41,14 @@
 namespace test {
 
 const dyld_all_image_infos* DyldGetAllImageInfos() {
-#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_13
+#if __MAC_OS_X_VERSION_MAX_ALLOWED < __MAC_10_13
   // When building with the pre-10.13 SDK, the weak_import declaration above is
   // available and a symbol will be present in the SDK to link against. If the
   // old interface is also available at run time (running on pre-10.13), use it.
   if (_dyld_get_all_image_infos) {
     return _dyld_get_all_image_infos();
   }
-#elif MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_13
+#elif __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_13
   // When building with the 10.13 SDK or later, but able to run on pre-10.13,
   // look for _dyld_get_all_image_infos in the same module that provides
   // _dyld_image_count. There’s no symbol in the SDK to link against, so this is
diff --git a/test/mac/mach_multiprocess.cc b/test/mac/mach_multiprocess.cc
index eaa6a17..01b242a 100644
--- a/test/mac/mach_multiprocess.cc
+++ b/test/mac/mach_multiprocess.cc
@@ -14,7 +14,7 @@
 
 #include "test/mac/mach_multiprocess.h"
 
-#include <AvailabilityMacros.h>
+#include <Availability.h>
 #include <bsm/libbsm.h>
 
 #include <memory>
@@ -150,7 +150,7 @@
   // and other processes will be able to look it up and send messages to it,
   // these checks disambiguate genuine failures later on in the test from those
   // that would occur if an errant process sends a message to this service.
-#if MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_8
+#if __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_8
   uid_t audit_auid;
   uid_t audit_euid;
   gid_t audit_egid;
diff --git a/util/mach/exc_server_variants.cc b/util/mach/exc_server_variants.cc
index e4c2d19..ed3dda7 100644
--- a/util/mach/exc_server_variants.cc
+++ b/util/mach/exc_server_variants.cc
@@ -14,7 +14,7 @@
 
 #include "util/mach/exc_server_variants.h"
 
-#include <AvailabilityMacros.h>
+#include <Availability.h>
 #include <string.h>
 
 #include <algorithm>
@@ -682,7 +682,7 @@
                                              exception_behavior_t behavior,
                                              bool set_thread_state) {
   if (exception == EXC_CRASH
-#if !defined(OS_IOS) && MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_11
+#if !defined(OS_IOS) && __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_11
       && MacOSXMinorVersion() >= 11
 #endif
      ) {
diff --git a/util/mach/exception_types.cc b/util/mach/exception_types.cc
index 2a1f3c0..a959eb5 100644
--- a/util/mach/exception_types.cc
+++ b/util/mach/exception_types.cc
@@ -15,11 +15,10 @@
 #include "util/mach/exception_types.h"
 
 #include <Availability.h>
-#include <AvailabilityMacros.h>
 #include <dlfcn.h>
 #include <errno.h>
-#include <libproc.h>
 #include <kern/exc_resource.h>
+#include <libproc.h>
 #include <strings.h>
 
 #include "base/check_op.h"
@@ -29,7 +28,7 @@
 #include "util/mach/mach_extensions.h"
 #include "util/numeric/in_range_cast.h"
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_9
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_9
 
 extern "C" {
 
@@ -83,13 +82,13 @@
 // present on OS X 10.9 and later. If it’s not available, sets errno to ENOSYS
 // and returns -1.
 int ProcGetWakemonParams(pid_t pid, int* rate_hz, int* flags) {
-#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_9
+#if __MAC_OS_X_VERSION_MAX_ALLOWED < __MAC_10_9
   // proc_get_wakemon_params() isn’t in the SDK. Look it up dynamically.
   static ProcGetWakemonParamsType proc_get_wakemon_params =
       GetProcGetWakemonParams();
 #endif
 
-#if MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_9
+#if __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_9
   // proc_get_wakemon_params() is definitely available if the deployment target
   // is 10.9 or newer.
   if (!proc_get_wakemon_params) {
diff --git a/util/mach/mach_extensions.cc b/util/mach/mach_extensions.cc
index cefb9bf..4b38cd5 100644
--- a/util/mach/mach_extensions.cc
+++ b/util/mach/mach_extensions.cc
@@ -15,7 +15,6 @@
 #include "util/mach/mach_extensions.h"
 
 #include <Availability.h>
-#include <AvailabilityMacros.h>
 #include <pthread.h>
 
 #include "base/mac/mach_logging.h"
@@ -50,7 +49,7 @@
 #error This code was not ported to iOS versions older than 7
 #endif
 
-#if !defined(OS_IOS) && MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_9
+#if !defined(OS_IOS) && __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_9
   const int mac_os_x_minor_version = MacOSXMinorVersion();
 #endif
 
@@ -67,7 +66,7 @@
       EXC_MASK_MACH_SYSCALL |
       EXC_MASK_RPC_ALERT |
       EXC_MASK_MACHINE;
-#if !defined(OS_IOS) && MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_8
+#if !defined(OS_IOS) && __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_8
   if (mac_os_x_minor_version < 8) {
     return kExcMaskAll_10_6;
   }
@@ -77,7 +76,7 @@
   // xnu-2050.48.11/osfmk/mach/exception_types.h.
   constexpr exception_mask_t kExcMaskAll_10_8 =
       kExcMaskAll_10_6 | EXC_MASK_RESOURCE;
-#if !defined(OS_IOS) && MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_9
+#if !defined(OS_IOS) && __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_9
   if (mac_os_x_minor_version < 9) {
     return kExcMaskAll_10_8;
   }
@@ -97,7 +96,7 @@
 #error This code was not ported to iOS versions older than 9
 #endif
 
-#if !defined(OS_IOS) && MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_11
+#if !defined(OS_IOS) && __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_11
   if (MacOSXMinorVersion() < 11) {
     return kExcMaskValid_10_6;
   }
diff --git a/util/mach/mach_message.cc b/util/mach/mach_message.cc
index 72d71e3..1443e14 100644
--- a/util/mach/mach_message.cc
+++ b/util/mach/mach_message.cc
@@ -14,7 +14,7 @@
 
 #include "util/mach/mach_message.h"
 
-#include <AvailabilityMacros.h>
+#include <Availability.h>
 
 #include <limits>
 
@@ -269,7 +269,7 @@
   const mach_msg_audit_trailer_t* audit_trailer =
       reinterpret_cast<const mach_msg_audit_trailer_t*>(trailer);
 
-#if MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_8
+#if __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_8
   pid_t audit_pid;
   audit_token_to_au32(audit_trailer->msgh_audit,
                       nullptr,
diff --git a/util/stdlib/objc.h b/util/stdlib/objc.h
index faaa453..b5e5b6c 100644
--- a/util/stdlib/objc.h
+++ b/util/stdlib/objc.h
@@ -15,10 +15,10 @@
 #ifndef CRASHPAD_UTIL_STDLIB_OBJC_H_
 #define CRASHPAD_UTIL_STDLIB_OBJC_H_
 
-#include <AvailabilityMacros.h>
+#include <Availability.h>
 #include <objc/objc.h>
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_8
+#if __MAC_OS_X_VERSION_MAX_ALLOWED < __MAC_10_8
 
 // In order for the @NO and @YES literals to work, NO and YES must be defined as
 // __objc_no and __objc_yes. See
diff --git a/util/stdlib/strnlen.cc b/util/stdlib/strnlen.cc
index 07b0db5..872c0eb 100644
--- a/util/stdlib/strnlen.cc
+++ b/util/stdlib/strnlen.cc
@@ -14,9 +14,9 @@
 
 #include "util/stdlib/strnlen.h"
 
-#if defined(OS_MAC) && MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_7
+#if defined(OS_MAC) && __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_7
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_7
 // Redeclare a method only available on Mac OS X 10.7 and later to suppress a
 // -Wpartial-availability warning.
 extern "C" {
@@ -27,7 +27,7 @@
 namespace crashpad {
 
 size_t strnlen(const char* string, size_t max_length) {
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+#if __MAC_OS_X_VERSION_MAX_ALLOWED >= __MAC_10_7
   if (::strnlen) {
     return ::strnlen(string, max_length);
   }
diff --git a/util/stdlib/strnlen.h b/util/stdlib/strnlen.h
index b88f2da..59253b7 100644
--- a/util/stdlib/strnlen.h
+++ b/util/stdlib/strnlen.h
@@ -21,7 +21,7 @@
 #include "build/build_config.h"
 
 #if defined(OS_MAC)
-#include <AvailabilityMacros.h>
+#include <Availability.h>
 #endif
 
 namespace crashpad {
@@ -38,7 +38,7 @@
 //!     and not all systems’ standard libraries provide an implementation.
 size_t strnlen(const char* string, size_t max_length);
 
-#if !defined(OS_MAC) || MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_7
+#if !defined(OS_MAC) || __MAC_OS_X_VERSION_MIN_REQUIRED >= __MAC_10_7
 inline size_t strnlen(const char* string, size_t max_length) {
   return ::strnlen(string, max_length);
 }