diff --git a/compiler/dex/quick/quick_cfi_test.cc b/compiler/dex/quick/quick_cfi_test.cc
index 8318b52..16c161e 100644
--- a/compiler/dex/quick/quick_cfi_test.cc
+++ b/compiler/dex/quick/quick_cfi_test.cc
@@ -36,7 +36,7 @@
 namespace art {
 
 // Run the tests only on host.
-#ifndef HAVE_ANDROID_OS
+#ifndef __ANDROID__
 
 class QuickCFITest : public CFITest {
  public:
@@ -136,6 +136,6 @@
 TEST_ISA(kMips)
 TEST_ISA(kMips64)
 
-#endif  // HAVE_ANDROID_OS
+#endif  // __ANDROID__
 
 }  // namespace art
diff --git a/compiler/dwarf/dwarf_test.cc b/compiler/dwarf/dwarf_test.cc
index 4d423d0..a07d27c 100644
--- a/compiler/dwarf/dwarf_test.cc
+++ b/compiler/dwarf/dwarf_test.cc
@@ -27,7 +27,7 @@
 namespace dwarf {
 
 // Run the tests only on host since we need objdump.
-#ifndef HAVE_ANDROID_OS
+#ifndef __ANDROID__
 
 constexpr CFIFormat kCFIFormat = DW_DEBUG_FRAME_FORMAT;
 
@@ -336,7 +336,7 @@
   CheckObjdumpOutput(is64bit, "-W");
 }
 
-#endif  // HAVE_ANDROID_OS
+#endif  // __ANDROID__
 
 }  // namespace dwarf
 }  // namespace art
diff --git a/compiler/jni/jni_cfi_test.cc b/compiler/jni/jni_cfi_test.cc
index 016f28e..0bfe8a2 100644
--- a/compiler/jni/jni_cfi_test.cc
+++ b/compiler/jni/jni_cfi_test.cc
@@ -28,7 +28,7 @@
 namespace art {
 
 // Run the tests only on host.
-#ifndef HAVE_ANDROID_OS
+#ifndef __ANDROID__
 
 class JNICFITest : public CFITest {
  public:
@@ -88,6 +88,6 @@
 TEST_ISA(kMips)
 TEST_ISA(kMips64)
 
-#endif  // HAVE_ANDROID_OS
+#endif  // __ANDROID__
 
 }  // namespace art
diff --git a/compiler/optimizing/optimizing_cfi_test.cc b/compiler/optimizing/optimizing_cfi_test.cc
index fe3bb1a..f455571 100644
--- a/compiler/optimizing/optimizing_cfi_test.cc
+++ b/compiler/optimizing/optimizing_cfi_test.cc
@@ -29,7 +29,7 @@
 namespace art {
 
 // Run the tests only on host.
-#ifndef HAVE_ANDROID_OS
+#ifndef __ANDROID__
 
 class OptimizingCFITest : public CFITest {
  public:
@@ -125,6 +125,6 @@
 TEST_ISA(kX86)
 TEST_ISA(kX86_64)
 
-#endif  // HAVE_ANDROID_OS
+#endif  // __ANDROID__
 
 }  // namespace art
diff --git a/compiler/utils/assembler_thumb_test.cc b/compiler/utils/assembler_thumb_test.cc
index 20f61f9..cb01cea 100644
--- a/compiler/utils/assembler_thumb_test.cc
+++ b/compiler/utils/assembler_thumb_test.cc
@@ -32,7 +32,7 @@
 // Include results file (generated manually)
 #include "assembler_thumb_test_expected.cc.inc"
 
-#ifndef HAVE_ANDROID_OS
+#ifndef __ANDROID__
 // This controls whether the results are printed to the
 // screen or compared against the expected output.
 // To generate new expected output, set this to true and
@@ -72,7 +72,7 @@
 }
 
 std::string GetToolsDir() {
-#ifndef HAVE_ANDROID_OS
+#ifndef __ANDROID__
   // This will only work on the host.  There is no as, objcopy or objdump on the device.
   static std::string toolsdir;
 
@@ -89,7 +89,7 @@
 }
 
 void DumpAndCheck(std::vector<uint8_t>& code, const char* testname, const char* const* results) {
-#ifndef HAVE_ANDROID_OS
+#ifndef __ANDROID__
   static std::string toolsdir = GetToolsDir();
 
   ScratchFile file;
diff --git a/compiler/utils/x86_64/assembler_x86_64_test.cc b/compiler/utils/x86_64/assembler_x86_64_test.cc
index 422138c..2c1a6a1 100644
--- a/compiler/utils/x86_64/assembler_x86_64_test.cc
+++ b/compiler/utils/x86_64/assembler_x86_64_test.cc
@@ -35,7 +35,7 @@
   ASSERT_EQ(static_cast<size_t>(5), buffer.Size());
 }
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 static constexpr size_t kRandomIterations = 1000;  // Devices might be puny, don't stress them...
 #else
 static constexpr size_t kRandomIterations = 100000;  // Hosts are pretty powerful.
diff --git a/runtime/arch/arm/instruction_set_features_arm.cc b/runtime/arch/arm/instruction_set_features_arm.cc
index f8590d3..28d1942 100644
--- a/runtime/arch/arm/instruction_set_features_arm.cc
+++ b/runtime/arch/arm/instruction_set_features_arm.cc
@@ -16,7 +16,7 @@
 
 #include "instruction_set_features_arm.h"
 
-#if defined(HAVE_ANDROID_OS) && defined(__arm__)
+#if defined(__ANDROID__) && defined(__arm__)
 #include <sys/auxv.h>
 #include <asm/hwcap.h>
 #endif
@@ -166,7 +166,7 @@
   bool has_div = false;
   bool has_lpae = false;
 
-#if defined(HAVE_ANDROID_OS) && defined(__arm__)
+#if defined(__ANDROID__) && defined(__arm__)
   uint64_t hwcaps = getauxval(AT_HWCAP);
   LOG(INFO) << "hwcaps=" << hwcaps;
   if ((hwcaps & HWCAP_IDIVT) != 0) {
diff --git a/runtime/arch/instruction_set_features_test.cc b/runtime/arch/instruction_set_features_test.cc
index e6f4e7a..99c2d4d 100644
--- a/runtime/arch/instruction_set_features_test.cc
+++ b/runtime/arch/instruction_set_features_test.cc
@@ -18,7 +18,7 @@
 
 #include <gtest/gtest.h>
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 #include "cutils/properties.h"
 #endif
 
@@ -26,7 +26,7 @@
 
 namespace art {
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 #if defined(__aarch64__)
 TEST(InstructionSetFeaturesTest, DISABLED_FeaturesFromSystemPropertyVariant) {
   LOG(WARNING) << "Test disabled due to no CPP define for A53 erratum 835769";
@@ -111,7 +111,7 @@
 }
 #endif
 
-#ifndef HAVE_ANDROID_OS
+#ifndef __ANDROID__
 TEST(InstructionSetFeaturesTest, HostFeaturesFromCppDefines) {
   std::string error_msg;
   std::unique_ptr<const InstructionSetFeatures> default_features(
diff --git a/runtime/base/logging.cc b/runtime/base/logging.cc
index 859de4b..7a620e3 100644
--- a/runtime/base/logging.cc
+++ b/runtime/base/logging.cc
@@ -26,7 +26,7 @@
 #include "utils.h"
 
 // Headers for LogMessage::LogLine.
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 #include "cutils/log.h"
 #else
 #include <sys/types.h>
@@ -47,7 +47,7 @@
 // Print INTERNAL_FATAL messages directly instead of at destruction time. This only works on the
 // host right now: for the device, a stream buf collating output into lines and calling LogLine or
 // lower-level logging is necessary.
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 static constexpr bool kPrintInternalFatalDirectly = false;
 #else
 static constexpr bool kPrintInternalFatalDirectly = !kIsTargetBuild;
@@ -234,7 +234,7 @@
   return data_->GetBuffer();
 }
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 static const android_LogPriority kLogSeverityToAndroidLogPriority[] = {
   ANDROID_LOG_VERBOSE, ANDROID_LOG_DEBUG, ANDROID_LOG_INFO, ANDROID_LOG_WARN,
   ANDROID_LOG_ERROR, ANDROID_LOG_FATAL, ANDROID_LOG_FATAL
@@ -245,7 +245,7 @@
 
 void LogMessage::LogLine(const char* file, unsigned int line, LogSeverity log_severity,
                          const char* message) {
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   const char* tag = ProgramInvocationShortName();
   int priority = kLogSeverityToAndroidLogPriority[log_severity];
   if (priority == ANDROID_LOG_FATAL) {
@@ -264,7 +264,7 @@
 
 void LogMessage::LogLineLowStack(const char* file, unsigned int line, LogSeverity log_severity,
                                  const char* message) {
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   // Use android_writeLog() to avoid stack-based buffers used by android_printLog().
   const char* tag = ProgramInvocationShortName();
   int priority = kLogSeverityToAndroidLogPriority[log_severity];
diff --git a/runtime/debugger.cc b/runtime/debugger.cc
index f0de65b..c9ae9b8 100644
--- a/runtime/debugger.cc
+++ b/runtime/debugger.cc
@@ -4626,7 +4626,7 @@
   // Send a series of heap segment chunks.
   HeapChunkContext context(what == HPSG_WHAT_MERGED_OBJECTS, native);
   if (native) {
-#if defined(HAVE_ANDROID_OS) && defined(USE_DLMALLOC)
+#if defined(__ANDROID__) && defined(USE_DLMALLOC)
     dlmalloc_inspect_all(HeapChunkContext::HeapChunkNativeCallback, &context);
     HeapChunkContext::HeapChunkNativeCallback(nullptr, nullptr, 0, &context);  // Indicate end of a space.
 #else
diff --git a/runtime/gc/allocation_record.cc b/runtime/gc/allocation_record.cc
index ec4d626..16c9354 100644
--- a/runtime/gc/allocation_record.cc
+++ b/runtime/gc/allocation_record.cc
@@ -20,7 +20,7 @@
 #include "base/stl_util.h"
 #include "stack.h"
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 #include "cutils/properties.h"
 #endif
 
@@ -42,7 +42,7 @@
 }
 
 void AllocRecordObjectMap::SetProperties() {
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   // Check whether there's a system property overriding the max number of records.
   const char* propertyName = "dalvik.vm.allocTrackerMax";
   char allocMaxString[PROPERTY_VALUE_MAX];
diff --git a/runtime/gc/allocator/dlmalloc.h b/runtime/gc/allocator/dlmalloc.h
index 0e91a43..0558921 100644
--- a/runtime/gc/allocator/dlmalloc.h
+++ b/runtime/gc/allocator/dlmalloc.h
@@ -35,7 +35,7 @@
 #include "../../bionic/libc/upstream-dlmalloc/malloc.h"
 #pragma GCC diagnostic pop
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 // Define dlmalloc routines from bionic that cannot be included directly because of redefining
 // symbols from the include above.
 extern "C" void dlmalloc_inspect_all(void(*handler)(void*, void *, size_t, void*), void* arg);
diff --git a/runtime/gc/allocator/rosalloc.cc b/runtime/gc/allocator/rosalloc.cc
index abaa97f..470bc1c 100644
--- a/runtime/gc/allocator/rosalloc.cc
+++ b/runtime/gc/allocator/rosalloc.cc
@@ -1170,7 +1170,7 @@
 
   // First mark slots to free in the bulk free bit map without locking the
   // size bracket locks. On host, unordered_set is faster than vector + flag.
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   std::vector<Run*> runs;
 #else
   std::unordered_set<Run*, hash_run, eq_run> runs;
@@ -1237,7 +1237,7 @@
     DCHECK_EQ(run->magic_num_, kMagicNum);
     // Set the bit in the bulk free bit map.
     freed_bytes += run->MarkBulkFreeBitMap(ptr);
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
     if (!run->to_be_bulk_freed_) {
       run->to_be_bulk_freed_ = true;
       runs.push_back(run);
@@ -1252,7 +1252,7 @@
   // union the bulk free bit map into the thread-local free bit map
   // (for thread-local runs.)
   for (Run* run : runs) {
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
     DCHECK(run->to_be_bulk_freed_);
     run->to_be_bulk_freed_ = false;
 #endif
diff --git a/runtime/gc/heap.cc b/runtime/gc/heap.cc
index 07309d8..5f617bd 100644
--- a/runtime/gc/heap.cc
+++ b/runtime/gc/heap.cc
@@ -1277,7 +1277,7 @@
   FinishGC(self, collector::kGcTypeNone);
   size_t native_reclaimed = 0;
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   // Only trim the native heap if we don't care about pauses.
   if (!CareAboutPauseTimes()) {
 #if defined(USE_DLMALLOC)
@@ -1290,7 +1290,7 @@
     UNIMPLEMENTED(WARNING) << "Add trimming support";
 #endif
   }
-#endif  // HAVE_ANDROID_OS
+#endif  // __ANDROID__
   uint64_t end_ns = NanoTime();
   VLOG(heap) << "Heap trim of managed (duration=" << PrettyDuration(gc_heap_end_ns - start_ns)
       << ", advised=" << PrettySize(managed_reclaimed) << ") and native (duration="
diff --git a/runtime/jdwp/jdwp_adb.cc b/runtime/jdwp/jdwp_adb.cc
index adc2912..51952c4 100644
--- a/runtime/jdwp/jdwp_adb.cc
+++ b/runtime/jdwp/jdwp_adb.cc
@@ -24,7 +24,7 @@
 #include "base/stringprintf.h"
 #include "jdwp/jdwp_priv.h"
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 #include "cutils/sockets.h"
 #endif
 
@@ -224,7 +224,7 @@
        */
       int  ret = connect(control_sock_, &control_addr_.controlAddrPlain, control_addr_len_);
       if (!ret) {
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
         if (!socket_peer_is_trusted(control_sock_)) {
           if (shutdown(control_sock_, SHUT_RDWR)) {
             PLOG(ERROR) << "trouble shutting down socket";
diff --git a/runtime/jdwp/jdwp_main.cc b/runtime/jdwp/jdwp_main.cc
index 260abe7..5a9a0f5 100644
--- a/runtime/jdwp/jdwp_main.cc
+++ b/runtime/jdwp/jdwp_main.cc
@@ -248,7 +248,7 @@
     case kJdwpTransportSocket:
       InitSocketTransport(state.get(), options);
       break;
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
     case kJdwpTransportAndroidAdb:
       InitAdbTransport(state.get(), options);
       break;
diff --git a/runtime/mem_map.cc b/runtime/mem_map.cc
index 8df8f96..d9ad7dc 100644
--- a/runtime/mem_map.cc
+++ b/runtime/mem_map.cc
@@ -280,7 +280,7 @@
   ScopedFd fd(-1);
 
 #ifdef USE_ASHMEM
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   const bool use_ashmem = true;
 #else
   // When not on Android ashmem is faked using files in /tmp. Ensure that such files won't
diff --git a/runtime/native/dalvik_system_VMRuntime.cc b/runtime/native/dalvik_system_VMRuntime.cc
index 7abc546..9ea339a 100644
--- a/runtime/native/dalvik_system_VMRuntime.cc
+++ b/runtime/native/dalvik_system_VMRuntime.cc
@@ -16,7 +16,7 @@
 
 #include "dalvik_system_VMRuntime.h"
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 extern "C" void android_set_application_target_sdk_version(uint32_t version);
 #endif
 #include <limits.h>
@@ -196,7 +196,7 @@
   // Note that targetSdkVersion may be 0, meaning "current".
   Runtime::Current()->SetTargetSdkVersion(target_sdk_version);
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   // This part is letting libc/dynamic linker know about current app's
   // target sdk version to enable compatibility workarounds.
   android_set_application_target_sdk_version(static_cast<uint32_t>(target_sdk_version));
diff --git a/runtime/native/java_lang_Runtime.cc b/runtime/native/java_lang_Runtime.cc
index abac815..856a3e7 100644
--- a/runtime/native/java_lang_Runtime.cc
+++ b/runtime/native/java_lang_Runtime.cc
@@ -31,10 +31,10 @@
 #include "verify_object-inl.h"
 
 #include <sstream>
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 // This function is provided by android linker.
 extern "C" void android_update_LD_LIBRARY_PATH(const char* ld_library_path);
-#endif  // HAVE_ANDROID_OS
+#endif  // __ANDROID__
 
 namespace art {
 
@@ -53,7 +53,7 @@
 }
 
 static void SetLdLibraryPath(JNIEnv* env, jstring javaLdLibraryPathJstr) {
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   if (javaLdLibraryPathJstr != nullptr) {
     ScopedUtfChars ldLibraryPath(env, javaLdLibraryPathJstr);
     if (ldLibraryPath.c_str() != nullptr) {
diff --git a/runtime/oat_file.cc b/runtime/oat_file.cc
index 098fe61..a23d94d 100644
--- a/runtime/oat_file.cc
+++ b/runtime/oat_file.cc
@@ -27,7 +27,7 @@
 #include <sstream>
 
 // dlopen_ext support from bionic.
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 #include "android/dlext.h"
 #endif
 
@@ -229,7 +229,7 @@
     *error_msg = StringPrintf("Failed to find absolute path for '%s'", elf_filename.c_str());
     return false;
   }
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   android_dlextinfo extinfo;
   extinfo.flags = ANDROID_DLEXT_FORCE_LOAD | ANDROID_DLEXT_FORCE_FIXED_VADDR;
   dlopen_handle_ = android_dlopen_ext(absolute_path.get(), RTLD_NOW, &extinfo);
diff --git a/runtime/prebuilt_tools_test.cc b/runtime/prebuilt_tools_test.cc
index 53bc876..a7f7bcd 100644
--- a/runtime/prebuilt_tools_test.cc
+++ b/runtime/prebuilt_tools_test.cc
@@ -23,7 +23,7 @@
 namespace art {
 
 // Run the tests only on host.
-#ifndef HAVE_ANDROID_OS
+#ifndef __ANDROID__
 
 class PrebuiltToolsTest : public CommonRuntimeTest {
 };
@@ -61,6 +61,6 @@
   }
 }
 
-#endif  // HAVE_ANDROID_OS
+#endif  // __ANDROID__
 
 }  // namespace art
diff --git a/runtime/thread.cc b/runtime/thread.cc
index 2b977af..b3efad0 100644
--- a/runtime/thread.cc
+++ b/runtime/thread.cc
@@ -2139,7 +2139,7 @@
   std::string str(ss.str());
   // log to stderr for debugging command line processes
   std::cerr << str;
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   // log to logcat for debugging frameworks processes
   LOG(INFO) << str;
 #endif
diff --git a/runtime/thread_linux.cc b/runtime/thread_linux.cc
index 9d54eba..9563b99 100644
--- a/runtime/thread_linux.cc
+++ b/runtime/thread_linux.cc
@@ -44,7 +44,7 @@
 
 void Thread::SetUpAlternateSignalStack() {
   // Create and set an alternate signal stack.
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   LOG(FATAL) << "Invalid use of alternate signal stack on Android";
 #endif
   stack_t ss;
diff --git a/sigchainlib/sigchain.cc b/sigchainlib/sigchain.cc
index 8e9d421..c984b17 100644
--- a/sigchainlib/sigchain.cc
+++ b/sigchainlib/sigchain.cc
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 #include <android/log.h>
 #else
 #include <stdarg.h>
@@ -103,7 +103,7 @@
   va_list ap;
   va_start(ap, format);
   vsnprintf(buf, sizeof(buf), format, ap);
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   __android_log_write(ANDROID_LOG_ERROR, "libsigchain", buf);
 #else
   std::cout << buf << "\n";
diff --git a/sigchainlib/sigchain_dummy.cc b/sigchainlib/sigchain_dummy.cc
index 8495a54..dfe0c6f 100644
--- a/sigchainlib/sigchain_dummy.cc
+++ b/sigchainlib/sigchain_dummy.cc
@@ -17,7 +17,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
 #include <android/log.h>
 #else
 #include <stdarg.h>
@@ -38,7 +38,7 @@
   va_list ap;
   va_start(ap, format);
   vsnprintf(buf, sizeof(buf), format, ap);
-#ifdef HAVE_ANDROID_OS
+#ifdef __ANDROID__
   __android_log_write(ANDROID_LOG_ERROR, "libsigchain", buf);
 #else
   std::cout << buf << "\n";
diff --git a/test/051-thread/thread_test.cc b/test/051-thread/thread_test.cc
index 2b8e675..4215207 100644
--- a/test/051-thread/thread_test.cc
+++ b/test/051-thread/thread_test.cc
@@ -28,7 +28,7 @@
 extern "C" JNIEXPORT jboolean JNICALL Java_Main_supportsThreadPriorities(
     JNIEnv* env ATTRIBUTE_UNUSED,
     jclass clazz ATTRIBUTE_UNUSED) {
-#if defined(HAVE_ANDROID_OS)
+#if defined(__ANDROID__)
   return JNI_TRUE;
 #else
   return JNI_FALSE;