diff --git a/services/audioflinger/fastpath/Android.bp b/services/audioflinger/fastpath/Android.bp
index fb49430..c4aa171 100644
--- a/services/audioflinger/fastpath/Android.bp
+++ b/services/audioflinger/fastpath/Android.bp
@@ -1,3 +1,11 @@
+package {
+    // See: http://go/android-license-faq
+    // A large-scale-change added 'default_applicable_licenses' to import
+    // all of the 'license_kinds' from "frameworks_base_license"
+    // to get the below license kinds:
+    //   SPDX-license-identifier-Apache-2.0
+    default_applicable_licenses: ["frameworks_av_services_audioflinger_license"],
+}
 
 fastpath_tidy_errors = [
     // https://clang.llvm.org/extra/clang-tidy/checks/list.html
@@ -58,19 +66,11 @@
     "-bugprone-parent-virtual-call",
     "-cert-dcl59-cpp",
     "-cert-err34-c",
-    "-google-build-namespaces",
-    "-google-build-using-namespace",
-    "-google-default-arguments",
     "-google-runtime-int",
-    "-misc-const-correctness",
     "-misc-non-private-member-variables-in-classes",
     "-modernize-concat-nested-namespaces",
     "-modernize-loop-convert",
     "-modernize-use-default-member-init",
-    "-modernize-use-equals-default",
-    "-modernize-use-nullptr",
-    "-modernize-use-override",
-    "-modernize-use-using",
     "-performance-no-int-to-ptr",
 ]
 
diff --git a/services/audioflinger/fastpath/AutoPark.h b/services/audioflinger/fastpath/AutoPark.h
index 83f6b7d..6e68327 100644
--- a/services/audioflinger/fastpath/AutoPark.h
+++ b/services/audioflinger/fastpath/AutoPark.h
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+#pragma once
+
 namespace android {
 
 // T is FastMixer or FastCapture
diff --git a/services/audioflinger/fastpath/FastCapture.cpp b/services/audioflinger/fastpath/FastCapture.cpp
index 2963202..5c76649 100644
--- a/services/audioflinger/fastpath/FastCapture.cpp
+++ b/services/audioflinger/fastpath/FastCapture.cpp
@@ -33,8 +33,8 @@
 /*static*/ const FastCaptureState FastCapture::sInitial;
 
 FastCapture::FastCapture() : FastThread("cycleC_ms", "loadC_us"),
-    mInputSource(NULL), mInputSourceGen(0), mPipeSink(NULL), mPipeSinkGen(0),
-    mReadBuffer(NULL), mReadBufferState(-1), mFormat(Format_Invalid), mSampleRate(0),
+    mInputSource(nullptr), mInputSourceGen(0), mPipeSink(nullptr), mPipeSinkGen(0),
+    mReadBuffer(nullptr), mReadBufferState(-1), mFormat(Format_Invalid), mSampleRate(0),
     // mDummyDumpState
     mTotalNativeFramesRead(0)
 {
@@ -44,10 +44,6 @@
     mDummyDumpState = &mDummyFastCaptureDumpState;
 }
 
-FastCapture::~FastCapture()
-{
-}
-
 FastCaptureStateQueue* FastCapture::sq()
 {
     return &mSQ;
@@ -95,11 +91,11 @@
     bool eitherChanged = false;
 
     // check for change in input HAL configuration
-    NBAIO_Format previousFormat = mFormat;
+    const NBAIO_Format previousFormat = mFormat;
     if (current->mInputSourceGen != mInputSourceGen) {
         mInputSource = current->mInputSource;
         mInputSourceGen = current->mInputSourceGen;
-        if (mInputSource == NULL) {
+        if (mInputSource == nullptr) {
             mFormat = Format_Invalid;
             mSampleRate = 0;
         } else {
@@ -122,19 +118,19 @@
     }
 
     // input source and pipe sink must be compatible
-    if (eitherChanged && mInputSource != NULL && mPipeSink != NULL) {
+    if (eitherChanged && mInputSource != nullptr && mPipeSink != nullptr) {
         ALOG_ASSERT(Format_isEqual(mFormat, mPipeSink->format()));
     }
 
     if ((!Format_isEqual(mFormat, previousFormat)) || (frameCount != previous->mFrameCount)) {
         // FIXME to avoid priority inversion, don't free here
         free(mReadBuffer);
-        mReadBuffer = NULL;
+        mReadBuffer = nullptr;
         if (frameCount > 0 && mSampleRate > 0) {
             // FIXME new may block for unbounded time at internal mutex of the heap
             //       implementation; it would be better to have normal capture thread allocate for
             //       us to avoid blocking here and to prevent possible priority inversion
-            size_t bufferSize = frameCount * Format_frameSize(mFormat);
+            const size_t bufferSize = frameCount * Format_frameSize(mFormat);
             (void)posix_memalign(&mReadBuffer, 32, bufferSize);
             memset(mReadBuffer, 0, bufferSize); // if posix_memalign fails, will segv here.
             mPeriodNs = (frameCount * 1000000000LL) / mSampleRate;      // 1.00
@@ -166,9 +162,9 @@
     AudioBufferProvider* fastPatchRecordBufferProvider = current->mFastPatchRecordBufferProvider;
     AudioBufferProvider::Buffer patchBuffer;
 
-    if (fastPatchRecordBufferProvider != 0) {
+    if (fastPatchRecordBufferProvider != nullptr) {
         patchBuffer.frameCount = ~0;
-        status_t status = fastPatchRecordBufferProvider->getNextBuffer(&patchBuffer);
+        const status_t status = fastPatchRecordBufferProvider->getNextBuffer(&patchBuffer);
         if (status != NO_ERROR) {
             frameCount = 0;
         } else if (patchBuffer.frameCount < frameCount) {
@@ -179,11 +175,11 @@
     }
 
     if ((command & FastCaptureState::READ) /*&& isWarm*/) {
-        ALOG_ASSERT(mInputSource != NULL);
-        ALOG_ASSERT(mReadBuffer != NULL);
+        ALOG_ASSERT(mInputSource != nullptr);
+        ALOG_ASSERT(mReadBuffer != nullptr);
         dumpState->mReadSequence++;
         ATRACE_BEGIN("read");
-        ssize_t framesRead = mInputSource->read(mReadBuffer, frameCount);
+        const ssize_t framesRead = mInputSource->read(mReadBuffer, frameCount);
         ATRACE_END();
         dumpState->mReadSequence++;
         if (framesRead >= 0) {
@@ -201,8 +197,8 @@
     }
 
     if (command & FastCaptureState::WRITE) {
-        ALOG_ASSERT(mPipeSink != NULL);
-        ALOG_ASSERT(mReadBuffer != NULL);
+        ALOG_ASSERT(mPipeSink != nullptr);
+        ALOG_ASSERT(mReadBuffer != nullptr);
         if (mReadBufferState < 0) {
             memset(mReadBuffer, 0, frameCount * Format_frameSize(mFormat));
             mReadBufferState = frameCount;
@@ -211,23 +207,23 @@
             if (current->mSilenceCapture) {
                 memset(mReadBuffer, 0, mReadBufferState * Format_frameSize(mFormat));
             }
-            ssize_t framesWritten = mPipeSink->write(mReadBuffer, mReadBufferState);
+            const ssize_t framesWritten = mPipeSink->write(mReadBuffer, mReadBufferState);
             audio_track_cblk_t* cblk = current->mCblk;
-            if (fastPatchRecordBufferProvider != 0) {
+            if (fastPatchRecordBufferProvider != nullptr) {
                 // This indicates the fast track is a patch record, update the cblk by
                 // calling releaseBuffer().
                 memcpy_by_audio_format(patchBuffer.raw, current->mFastPatchRecordFormat,
                         mReadBuffer, mFormat.mFormat, framesWritten * mFormat.mChannelCount);
                 patchBuffer.frameCount = framesWritten;
                 fastPatchRecordBufferProvider->releaseBuffer(&patchBuffer);
-            } else if (cblk != NULL && framesWritten > 0) {
+            } else if (cblk != nullptr && framesWritten > 0) {
                 // FIXME This supports at most one fast capture client.
                 //       To handle multiple clients this could be converted to an array,
                 //       or with a lot more work the control block could be shared by all clients.
-                int32_t rear = cblk->u.mStreaming.mRear;
+                const int32_t rear = cblk->u.mStreaming.mRear;
                 android_atomic_release_store(framesWritten + rear, &cblk->u.mStreaming.mRear);
                 cblk->mServer += framesWritten;
-                int32_t old = android_atomic_or(CBLK_FUTEX_WAKE, &cblk->mFutex);
+                const int32_t old = android_atomic_or(CBLK_FUTEX_WAKE, &cblk->mFutex);
                 if (!(old & CBLK_FUTEX_WAKE)) {
                     // client is never in server process, so don't use FUTEX_WAKE_PRIVATE
                     (void) syscall(__NR_futex, &cblk->mFutex, FUTEX_WAKE, 1);
diff --git a/services/audioflinger/fastpath/FastCapture.h b/services/audioflinger/fastpath/FastCapture.h
index c3817c0..657a324 100644
--- a/services/audioflinger/fastpath/FastCapture.h
+++ b/services/audioflinger/fastpath/FastCapture.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_AUDIO_FAST_CAPTURE_H
-#define ANDROID_AUDIO_FAST_CAPTURE_H
+#pragma once
 
 #include "FastThread.h"
 #include "StateQueue.h"
@@ -24,13 +23,12 @@
 
 namespace android {
 
-typedef StateQueue<FastCaptureState> FastCaptureStateQueue;
+using FastCaptureStateQueue = StateQueue<FastCaptureState>;
 
 class FastCapture : public FastThread {
 
 public:
             FastCapture();
-    virtual ~FastCapture();
 
             FastCaptureStateQueue*  sq();
 
@@ -38,13 +36,13 @@
             FastCaptureStateQueue   mSQ;
 
     // callouts
-    virtual const FastThreadState *poll();
-    virtual void setNBLogWriter(NBLog::Writer *logWriter);
-    virtual void onIdle();
-    virtual void onExit();
-    virtual bool isSubClassCommand(FastThreadState::Command command);
-    virtual void onStateChange();
-    virtual void onWork();
+    const FastThreadState *poll() override;
+    void setNBLogWriter(NBLog::Writer *logWriter) override;
+    void onIdle() override;
+    void onExit() override;
+    bool isSubClassCommand(FastThreadState::Command command) override;
+    void onStateChange() override;
+    void onWork() override;
 
     static const FastCaptureState sInitial;
 
@@ -65,5 +63,3 @@
 };  // class FastCapture
 
 }   // namespace android
-
-#endif  // ANDROID_AUDIO_FAST_CAPTURE_H
diff --git a/services/audioflinger/fastpath/FastCaptureDumpState.cpp b/services/audioflinger/fastpath/FastCaptureDumpState.cpp
index 243dfa5..e0ac9cc 100644
--- a/services/audioflinger/fastpath/FastCaptureDumpState.cpp
+++ b/services/audioflinger/fastpath/FastCaptureDumpState.cpp
@@ -29,19 +29,15 @@
 {
 }
 
-FastCaptureDumpState::~FastCaptureDumpState()
-{
-}
-
 void FastCaptureDumpState::dump(int fd) const
 {
     if (mCommand == FastCaptureState::INITIAL) {
         dprintf(fd, "  FastCapture not initialized\n");
         return;
     }
-    double measuredWarmupMs = (mMeasuredWarmupTs.tv_sec * 1000.0) +
+    const double measuredWarmupMs = (mMeasuredWarmupTs.tv_sec * 1000.0) +
             (mMeasuredWarmupTs.tv_nsec / 1000000.0);
-    double periodSec = (double) mFrameCount / mSampleRate;
+    const double periodSec = (double) mFrameCount / mSampleRate;
     dprintf(fd, "  FastCapture command=%s readSequence=%u framesRead=%u\n"
                 "              readErrors=%u sampleRate=%u frameCount=%zu\n"
                 "              measuredWarmup=%.3g ms, warmupCycles=%u period=%.2f ms\n"
diff --git a/services/audioflinger/fastpath/FastCaptureDumpState.h b/services/audioflinger/fastpath/FastCaptureDumpState.h
index 34ce456..e205518 100644
--- a/services/audioflinger/fastpath/FastCaptureDumpState.h
+++ b/services/audioflinger/fastpath/FastCaptureDumpState.h
@@ -14,10 +14,10 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_AUDIO_FAST_CAPTURE_DUMP_STATE_H
-#define ANDROID_AUDIO_FAST_CAPTURE_DUMP_STATE_H
+#pragma once
 
 #include <stdint.h>
+#include <type_traits>
 #include "Configuration.h"
 #include "FastThreadDumpState.h"
 
@@ -25,7 +25,6 @@
 
 struct FastCaptureDumpState : FastThreadDumpState {
     FastCaptureDumpState();
-    /*virtual*/ ~FastCaptureDumpState();
 
     void dump(int fd) const;    // should only be called on a stable copy, not the original
 
@@ -38,6 +37,7 @@
     bool     mSilenced = false; // capture is silenced
 };
 
-}  // namespace android
+// No virtuals
+static_assert(!std::is_polymorphic_v<FastCaptureDumpState>);
 
-#endif  // ANDROID_AUDIO_FAST_CAPTURE_DUMP_STATE_H
+}  // namespace android
diff --git a/services/audioflinger/fastpath/FastCaptureState.cpp b/services/audioflinger/fastpath/FastCaptureState.cpp
index 918ba9c..d2df62a 100644
--- a/services/audioflinger/fastpath/FastCaptureState.cpp
+++ b/services/audioflinger/fastpath/FastCaptureState.cpp
@@ -19,11 +19,7 @@
 namespace android {
 
 FastCaptureState::FastCaptureState() : FastThreadState(),
-    mInputSource(NULL), mInputSourceGen(0), mPipeSink(NULL), mPipeSinkGen(0), mFrameCount(0)
-{
-}
-
-FastCaptureState::~FastCaptureState()
+    mInputSource(nullptr), mInputSourceGen(0), mPipeSink(nullptr), mPipeSinkGen(0), mFrameCount(0)
 {
 }
 
@@ -31,7 +27,7 @@
 const char *FastCaptureState::commandToString(Command command)
 {
     const char *str = FastThreadState::commandToString(command);
-    if (str != NULL) {
+    if (str != nullptr) {
         return str;
     }
     switch (command) {
diff --git a/services/audioflinger/fastpath/FastCaptureState.h b/services/audioflinger/fastpath/FastCaptureState.h
index f949275..82ea0ed 100644
--- a/services/audioflinger/fastpath/FastCaptureState.h
+++ b/services/audioflinger/fastpath/FastCaptureState.h
@@ -14,9 +14,9 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_AUDIO_FAST_CAPTURE_STATE_H
-#define ANDROID_AUDIO_FAST_CAPTURE_STATE_H
+#pragma once
 
+#include <type_traits>
 #include <media/nbaio/NBAIO.h>
 #include <media/AudioBufferProvider.h>
 #include "FastThreadState.h"
@@ -27,7 +27,6 @@
 // Represent a single state of the fast capture
 struct FastCaptureState : FastThreadState {
                 FastCaptureState();
-    /*virtual*/ ~FastCaptureState();
 
     // all pointer fields use raw pointers; objects are owned and ref-counted by RecordThread
     NBAIO_Source*   mInputSource;       // HAL input device, must already be negotiated
@@ -55,6 +54,7 @@
     static const char *commandToString(Command command);
 };  // struct FastCaptureState
 
-}   // namespace android
+// No virtuals.
+static_assert(!std::is_polymorphic_v<FastCaptureState>);
 
-#endif  // ANDROID_AUDIO_FAST_CAPTURE_STATE_H
+}   // namespace android
diff --git a/services/audioflinger/fastpath/FastMixer.cpp b/services/audioflinger/fastpath/FastMixer.cpp
index 080b0a6..e13adab 100644
--- a/services/audioflinger/fastpath/FastMixer.cpp
+++ b/services/audioflinger/fastpath/FastMixer.cpp
@@ -61,13 +61,13 @@
     : FastThread("cycle_ms", "load_us"),
     // mFastTrackNames
     // mGenerations
-    mOutputSink(NULL),
+    mOutputSink(nullptr),
     mOutputSinkGen(0),
-    mMixer(NULL),
-    mSinkBuffer(NULL),
+    mMixer(nullptr),
+    mSinkBuffer(nullptr),
     mSinkBufferSize(0),
     mSinkChannelCount(FCC_2),
-    mMixerBuffer(NULL),
+    mMixerBuffer(nullptr),
     mMixerBufferSize(0),
     mMixerBufferState(UNDEFINED),
     mFormat(Format_Invalid),
@@ -99,10 +99,6 @@
 #endif
 }
 
-FastMixer::~FastMixer()
-{
-}
-
 FastMixerStateQueue* FastMixer::sq()
 {
     return &mSQ;
@@ -229,13 +225,13 @@
     unsigned previousTrackMask;
 
     // check for change in output HAL configuration
-    NBAIO_Format previousFormat = mFormat;
+    const NBAIO_Format previousFormat = mFormat;
     if (current->mOutputSinkGen != mOutputSinkGen) {
         mOutputSink = current->mOutputSink;
         mOutputSinkGen = current->mOutputSinkGen;
         mSinkChannelMask = current->mSinkChannelMask;
         mBalance.setChannelMask(mSinkChannelMask);
-        if (mOutputSink == NULL) {
+        if (mOutputSink == nullptr) {
             mFormat = Format_Invalid;
             mSampleRate = 0;
             mSinkChannelCount = 0;
@@ -259,11 +255,11 @@
     if ((!Format_isEqual(mFormat, previousFormat)) || (frameCount != previous->mFrameCount)) {
         // FIXME to avoid priority inversion, don't delete here
         delete mMixer;
-        mMixer = NULL;
+        mMixer = nullptr;
         free(mMixerBuffer);
-        mMixerBuffer = NULL;
+        mMixerBuffer = nullptr;
         free(mSinkBuffer);
-        mSinkBuffer = NULL;
+        mSinkBuffer = nullptr;
         if (frameCount > 0 && mSampleRate > 0) {
             // FIXME new may block for unbounded time at internal mutex of the heap
             //       implementation; it would be better to have normal mixer allocate for us
@@ -320,7 +316,7 @@
         // process removed tracks first to avoid running out of track names
         unsigned removedTracks = previousTrackMask & ~currentTrackMask;
         while (removedTracks != 0) {
-            int i = __builtin_ctz(removedTracks);
+            const int i = __builtin_ctz(removedTracks);
             removedTracks &= ~(1 << i);
             updateMixerTrack(i, REASON_REMOVE);
             // don't reset track dump state, since other side is ignoring it
@@ -329,7 +325,7 @@
         // now process added tracks
         unsigned addedTracks = currentTrackMask & ~previousTrackMask;
         while (addedTracks != 0) {
-            int i = __builtin_ctz(addedTracks);
+            const int i = __builtin_ctz(addedTracks);
             addedTracks &= ~(1 << i);
             updateMixerTrack(i, REASON_ADD);
         }
@@ -338,7 +334,7 @@
         // but may have a different buffer provider or volume provider
         unsigned modifiedTracks = currentTrackMask & previousTrackMask;
         while (modifiedTracks != 0) {
-            int i = __builtin_ctz(modifiedTracks);
+            const int i = __builtin_ctz(modifiedTracks);
             modifiedTracks &= ~(1 << i);
             updateMixerTrack(i, REASON_MODIFY);
         }
@@ -373,8 +369,8 @@
     const FastMixerState::Command command = mCommand;
     const size_t frameCount = current->mFrameCount;
 
-    if ((command & FastMixerState::MIX) && (mMixer != NULL) && mIsWarm) {
-        ALOG_ASSERT(mMixerBuffer != NULL);
+    if ((command & FastMixerState::MIX) && (mMixer != nullptr) && mIsWarm) {
+        ALOG_ASSERT(mMixerBuffer != nullptr);
 
         // AudioMixer::mState.enabledTracks is undefined if mState.hook == process__validate,
         // so we keep a side copy of enabledTracks
@@ -383,7 +379,7 @@
         // for each track, update volume and check for underrun
         unsigned currentTrackMask = current->mTrackMask;
         while (currentTrackMask != 0) {
-            int i = __builtin_ctz(currentTrackMask);
+            const int i = __builtin_ctz(currentTrackMask);
             currentTrackMask &= ~(1 << i);
             const FastTrack* fastTrack = &current->mFastTracks[i];
 
@@ -406,8 +402,8 @@
             fastTrack->mBufferProvider->onTimestamp(perTrackTimestamp);
 
             const int name = i;
-            if (fastTrack->mVolumeProvider != NULL) {
-                gain_minifloat_packed_t vlr = fastTrack->mVolumeProvider->getVolumeLR();
+            if (fastTrack->mVolumeProvider != nullptr) {
+                const gain_minifloat_packed_t vlr = fastTrack->mVolumeProvider->getVolumeLR();
                 float vlf = float_from_gain(gain_minifloat_unpack_left(vlr));
                 float vrf = float_from_gain(gain_minifloat_unpack_right(vlr));
 
@@ -418,7 +414,7 @@
             // takes a tryLock, which can block
             // up to 1 ms.  If enough active tracks all blocked in sequence, this would result
             // in the overall fast mix cycle being delayed.  Should use a non-blocking FIFO.
-            size_t framesReady = fastTrack->mBufferProvider->framesReady();
+            const size_t framesReady = fastTrack->mBufferProvider->framesReady();
             if (ATRACE_ENABLED()) {
                 // I wish we had formatted trace names
                 char traceName[16];
@@ -464,7 +460,8 @@
         mMixerBufferState = UNDEFINED;
     }
     //bool didFullWrite = false;    // dumpsys could display a count of partial writes
-    if ((command & FastMixerState::WRITE) && (mOutputSink != NULL) && (mMixerBuffer != NULL)) {
+    if ((command & FastMixerState::WRITE)
+            && (mOutputSink != nullptr) && (mMixerBuffer != nullptr)) {
         if (mMixerBufferState == UNDEFINED) {
             memset(mMixerBuffer, 0, mMixerBufferSize);
             mMixerBufferState = ZEROED;
@@ -481,7 +478,7 @@
         mBalance.process((float *)mMixerBuffer, frameCount);
 
         // prepare the buffer used to write to sink
-        void *buffer = mSinkBuffer != NULL ? mSinkBuffer : mMixerBuffer;
+        void *buffer = mSinkBuffer != nullptr ? mSinkBuffer : mMixerBuffer;
         if (mFormat.mFormat != mMixerBufferFormat) { // sink format not the same as mixer format
             memcpy_by_audio_format(buffer, mFormat.mFormat, mMixerBuffer, mMixerBufferFormat,
                     frameCount * Format_channelCount(mFormat));
@@ -493,7 +490,7 @@
                     audio_bytes_per_sample(mFormat.mFormat),
                     frameCount * audio_bytes_per_frame(mAudioChannelCount, mFormat.mFormat));
         }
-        // if non-NULL, then duplicate write() to this non-blocking sink
+        // if non-nullptr, then duplicate write() to this non-blocking sink
 #ifdef TEE_SINK
         mTee.write(buffer, frameCount);
 #endif
@@ -501,7 +498,7 @@
         //       but this code should be modified to handle both non-blocking and blocking sinks
         dumpState->mWriteSequence++;
         ATRACE_BEGIN("write");
-        ssize_t framesWritten = mOutputSink->write(buffer, frameCount);
+        const ssize_t framesWritten = mOutputSink->write(buffer, frameCount);
         ATRACE_END();
         dumpState->mWriteSequence++;
         if (framesWritten >= 0) {
diff --git a/services/audioflinger/fastpath/FastMixer.h b/services/audioflinger/fastpath/FastMixer.h
index 9847507..ab7bfe1 100644
--- a/services/audioflinger/fastpath/FastMixer.h
+++ b/services/audioflinger/fastpath/FastMixer.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_AUDIO_FAST_MIXER_H
-#define ANDROID_AUDIO_FAST_MIXER_H
+#pragma once
 
 #include <atomic>
 #include <audio_utils/Balance.h>
@@ -29,7 +28,7 @@
 
 class AudioMixer;
 
-typedef StateQueue<FastMixerState> FastMixerStateQueue;
+using FastMixerStateQueue = StateQueue<FastMixerState>;
 
 class FastMixer : public FastThread {
 
@@ -37,7 +36,6 @@
     /** FastMixer constructor takes as param the parent MixerThread's io handle (id)
         for purposes of identification. */
     explicit FastMixer(audio_io_handle_t threadIoHandle);
-    virtual ~FastMixer();
 
             FastMixerStateQueue* sq();
 
@@ -51,13 +49,13 @@
             FastMixerStateQueue mSQ;
 
     // callouts
-    virtual const FastThreadState *poll();
-    virtual void setNBLogWriter(NBLog::Writer *logWriter);
-    virtual void onIdle();
-    virtual void onExit();
-    virtual bool isSubClassCommand(FastThreadState::Command command);
-    virtual void onStateChange();
-    virtual void onWork();
+    const FastThreadState *poll() override;
+    void setNBLogWriter(NBLog::Writer *logWriter) override;
+    void onIdle() override;
+    void onExit() override;
+    bool isSubClassCommand(FastThreadState::Command command) override;
+    void onStateChange() override;
+    void onWork() override;
 
     enum Reason {
         REASON_REMOVE,
@@ -115,5 +113,3 @@
 };  // class FastMixer
 
 }   // namespace android
-
-#endif  // ANDROID_AUDIO_FAST_MIXER_H
diff --git a/services/audioflinger/fastpath/FastMixerDumpState.cpp b/services/audioflinger/fastpath/FastMixerDumpState.cpp
index d041882..f48f539 100644
--- a/services/audioflinger/fastpath/FastMixerDumpState.cpp
+++ b/services/audioflinger/fastpath/FastMixerDumpState.cpp
@@ -37,15 +37,11 @@
 {
 }
 
-FastMixerDumpState::~FastMixerDumpState()
-{
-}
-
 // helper function called by qsort()
 static int compare_uint32_t(const void *pa, const void *pb)
 {
-    uint32_t a = *(const uint32_t *)pa;
-    uint32_t b = *(const uint32_t *)pb;
+    const uint32_t a = *(const uint32_t *)pa;
+    const uint32_t b = *(const uint32_t *)pb;
     if (a < b) {
         return -1;
     } else if (a > b) {
@@ -61,9 +57,9 @@
         dprintf(fd, "  FastMixer not initialized\n");
         return;
     }
-    double measuredWarmupMs = (mMeasuredWarmupTs.tv_sec * 1000.0) +
+    const double measuredWarmupMs = (mMeasuredWarmupTs.tv_sec * 1000.0) +
             (mMeasuredWarmupTs.tv_nsec / 1000000.0);
-    double mixPeriodSec = (double) mFrameCount / mSampleRate;
+    const double mixPeriodSec = (double) mFrameCount / mSampleRate;
     dprintf(fd, "  FastMixer command=%s writeSequence=%u framesWritten=%u\n"
                 "            numTracks=%u writeErrors=%u underruns=%u overruns=%u\n"
                 "            sampleRate=%u frameCount=%zu measuredWarmup=%.3g ms, warmupCycles=%u\n"
@@ -99,16 +95,16 @@
     // the mean account for 99.73% of the population.  So if we take each tail to be 1/1000 of the
     // sample set, we get 99.8% combined, or close to three standard deviations.
     static const uint32_t kTailDenominator = 1000;
-    uint32_t *tail = n >= kTailDenominator ? new uint32_t[n] : NULL;
+    uint32_t *tail = n >= kTailDenominator ? new uint32_t[n] : nullptr;
     // loop over all the samples
     for (uint32_t j = 0; j < n; ++j) {
-        size_t i = oldestClosed++ & (mSamplingN - 1);
-        uint32_t wallNs = mMonotonicNs[i];
-        if (tail != NULL) {
+        const size_t i = oldestClosed++ & (mSamplingN - 1);
+        const uint32_t wallNs = mMonotonicNs[i];
+        if (tail != nullptr) {
             tail[j] = wallNs;
         }
         wall.add(wallNs);
-        uint32_t sampleLoadNs = mLoadNs[i];
+        const uint32_t sampleLoadNs = mLoadNs[i];
         loadNs.add(sampleLoadNs);
 #ifdef CPU_FREQUENCY_STATISTICS
         uint32_t sampleCpukHz = mCpukHz[i];
@@ -146,10 +142,10 @@
                 "    mean=%.1f min=%.1f max=%.1f stddev=%.1f\n",
                 loadMHz.getMean(), loadMHz.getMin(), loadMHz.getMax(), loadMHz.getStdDev());
 #endif
-    if (tail != NULL) {
+    if (tail != nullptr) {
         qsort(tail, n, sizeof(uint32_t), compare_uint32_t);
         // assume same number of tail samples on each side, left and right
-        uint32_t count = n / kTailDenominator;
+        const uint32_t count = n / kTailDenominator;
         audio_utils::Statistics<double> left, right;
         for (uint32_t i = 0; i < count; ++i) {
             left.add(tail[i]);
@@ -175,7 +171,7 @@
             FastMixerState::sMaxFastTracks, trackMask);
     dprintf(fd, "  Index Active Full Partial Empty  Recent Ready    Written\n");
     for (uint32_t i = 0; i < FastMixerState::sMaxFastTracks; ++i, trackMask >>= 1) {
-        bool isActive = trackMask & 1;
+        const bool isActive = trackMask & 1;
         const FastTrackDump *ftDump = &mTracks[i];
         const FastTrackUnderruns& underruns = ftDump->mUnderruns;
         const char *mostRecent;
diff --git a/services/audioflinger/fastpath/FastMixerDumpState.h b/services/audioflinger/fastpath/FastMixerDumpState.h
index 294ef78..91d85b1 100644
--- a/services/audioflinger/fastpath/FastMixerDumpState.h
+++ b/services/audioflinger/fastpath/FastMixerDumpState.h
@@ -14,10 +14,10 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_AUDIO_FAST_MIXER_DUMP_STATE_H
-#define ANDROID_AUDIO_FAST_MIXER_DUMP_STATE_H
+#pragma once
 
 #include <stdint.h>
+#include <type_traits>
 #include <audio_utils/TimestampVerifier.h>
 #include "Configuration.h"
 #include "FastThreadDumpState.h"
@@ -55,15 +55,16 @@
 // Represents the dump state of a fast track
 struct FastTrackDump {
     FastTrackDump() : mFramesReady(0) { }
-    /*virtual*/ ~FastTrackDump() { }
     FastTrackUnderruns  mUnderruns;
     size_t              mFramesReady;        // most recent value only; no long-term statistics kept
     int64_t             mFramesWritten;      // last value from track
 };
 
+// No virtuals.
+static_assert(!std::is_polymorphic_v<FastTrackDump>);
+
 struct FastMixerDumpState : FastThreadDumpState {
     FastMixerDumpState();
-    /*virtual*/ ~FastMixerDumpState();
 
     void dump(int fd) const;    // should only be called on a stable copy, not the original
 
@@ -81,6 +82,7 @@
     TimestampVerifier<int64_t /* frame count */, int64_t /* time ns */> mTimestampVerifier;
 };
 
-}  // namespace android
+// No virtuals.
+static_assert(!std::is_polymorphic_v<FastMixerDumpState>);
 
-#endif  // ANDROID_AUDIO_FAST_MIXER_DUMP_STATE_H
+}  // namespace android
diff --git a/services/audioflinger/fastpath/FastMixerState.cpp b/services/audioflinger/fastpath/FastMixerState.cpp
index b98842d..dbccb10 100644
--- a/services/audioflinger/fastpath/FastMixerState.cpp
+++ b/services/audioflinger/fastpath/FastMixerState.cpp
@@ -23,30 +23,22 @@
 namespace android {
 
 FastTrack::FastTrack() :
-    mBufferProvider(NULL), mVolumeProvider(NULL),
+    mBufferProvider(nullptr), mVolumeProvider(nullptr),
     mChannelMask(AUDIO_CHANNEL_OUT_STEREO), mFormat(AUDIO_FORMAT_INVALID), mGeneration(0)
 {
 }
 
-FastTrack::~FastTrack()
-{
-}
-
 FastMixerState::FastMixerState() : FastThreadState(),
     // mFastTracks
-    mFastTracksGen(0), mTrackMask(0), mOutputSink(NULL), mOutputSinkGen(0),
+    mFastTracksGen(0), mTrackMask(0), mOutputSink(nullptr), mOutputSinkGen(0),
     mFrameCount(0)
 {
-    int ok = pthread_once(&sMaxFastTracksOnce, sMaxFastTracksInit);
+    const int ok = pthread_once(&sMaxFastTracksOnce, sMaxFastTracksInit);
     if (ok != 0) {
         ALOGE("%s pthread_once failed: %d", __func__, ok);
     }
 }
 
-FastMixerState::~FastMixerState()
-{
-}
-
 // static
 unsigned FastMixerState::sMaxFastTracks = kDefaultFastTracks;
 
@@ -57,7 +49,7 @@
 const char *FastMixerState::commandToString(Command command)
 {
     const char *str = FastThreadState::commandToString(command);
-    if (str != NULL) {
+    if (str != nullptr) {
         return str;
     }
     switch (command) {
@@ -72,9 +64,9 @@
 void FastMixerState::sMaxFastTracksInit()
 {
     char value[PROPERTY_VALUE_MAX];
-    if (property_get("ro.audio.max_fast_tracks", value, NULL) > 0) {
+    if (property_get("ro.audio.max_fast_tracks", value, nullptr /* default_value */) > 0) {
         char *endptr;
-        unsigned long ul = strtoul(value, &endptr, 0);
+        const unsigned long ul = strtoul(value, &endptr, 0);
         if (*endptr == '\0' && kMinFastTracks <= ul && ul <= kMaxFastTracks) {
             sMaxFastTracks = (unsigned) ul;
         }
diff --git a/services/audioflinger/fastpath/FastMixerState.h b/services/audioflinger/fastpath/FastMixerState.h
index ce3cc14..f40f612 100644
--- a/services/audioflinger/fastpath/FastMixerState.h
+++ b/services/audioflinger/fastpath/FastMixerState.h
@@ -14,10 +14,10 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_AUDIO_FAST_MIXER_STATE_H
-#define ANDROID_AUDIO_FAST_MIXER_STATE_H
+#pragma once
 
 #include <math.h>
+#include <type_traits>
 
 #include <audio_utils/minifloat.h>
 #include <system/audio.h>
@@ -38,13 +38,12 @@
     virtual gain_minifloat_packed_t getVolumeLR() = 0;
 protected:
     VolumeProvider() { }
-    virtual ~VolumeProvider() { }
+    virtual ~VolumeProvider() = default;
 };
 
 // Represents the state of a fast track
 struct FastTrack {
     FastTrack();
-    /*virtual*/ ~FastTrack();
 
     ExtendedAudioBufferProvider* mBufferProvider; // must be NULL if inactive, or non-NULL if active
     VolumeProvider*         mVolumeProvider; // optional; if NULL then full-scale
@@ -56,10 +55,12 @@
     float                   mHapticMaxAmplitude = NAN; // max amplitude allowed for haptic data
 };
 
+// No virtuals.
+static_assert(!std::is_polymorphic_v<FastTrack>);
+
 // Represents a single state of the fast mixer
 struct FastMixerState : FastThreadState {
                 FastMixerState();
-    /*virtual*/ ~FastMixerState();
 
     // These are the minimum, maximum, and default values for maximum number of fast tracks
     static const unsigned kMinFastTracks = 2;
@@ -95,6 +96,7 @@
 
 };  // struct FastMixerState
 
-}   // namespace android
+// No virtuals.
+static_assert(!std::is_polymorphic_v<FastMixerState>);
 
-#endif  // ANDROID_AUDIO_FAST_MIXER_STATE_H
+}   // namespace android
diff --git a/services/audioflinger/fastpath/FastThread.cpp b/services/audioflinger/fastpath/FastThread.cpp
index cadbbec..77071dc 100644
--- a/services/audioflinger/fastpath/FastThread.cpp
+++ b/services/audioflinger/fastpath/FastThread.cpp
@@ -40,7 +40,7 @@
 
 FastThread::FastThread(const char *cycleMs, const char *loadUs) : Thread(false /*canCallJava*/),
     // re-initialized to &sInitial by subclass constructor
-    mPrevious(NULL), mCurrent(NULL),
+    mPrevious(nullptr), mCurrent(nullptr),
     /* mOldTs({0, 0}), */
     mOldTsValid(false),
     mSleepNs(-1),
@@ -51,8 +51,8 @@
     mWarmupNsMin(0),
     mWarmupNsMax(LONG_MAX),
     // re-initialized to &mDummySubclassDumpState by subclass constructor
-    mDummyDumpState(NULL),
-    mDumpState(NULL),
+    mDummyDumpState(nullptr),
+    mDumpState(nullptr),
     mIgnoreNextOverrun(true),
 #ifdef FAST_THREAD_STATISTICS
     // mOldLoad
@@ -84,10 +84,6 @@
     strlcpy(mLoadUs, loadUs, sizeof(mLoadUs));
 }
 
-FastThread::~FastThread()
-{
-}
-
 bool FastThread::threadLoop()
 {
     // LOGT now works even if tlNBLogWriter is nullptr, but we're considering changing that,
@@ -100,7 +96,7 @@
             if (mSleepNs > 0) {
                 ALOG_ASSERT(mSleepNs < 1000000000);
                 const struct timespec req = {0, mSleepNs};
-                nanosleep(&req, NULL);
+                nanosleep(&req, nullptr);
             } else {
                 sched_yield();
             }
@@ -110,7 +106,7 @@
 
         // poll for state change
         const FastThreadState *next = poll();
-        if (next == NULL) {
+        if (next == nullptr) {
             // continue to use the default initial state until a real state is available
             // FIXME &sInitial not available, should save address earlier
             //ALOG_ASSERT(mCurrent == &sInitial && previous == &sInitial);
@@ -121,8 +117,8 @@
         if (next != mCurrent) {
 
             // As soon as possible of learning of a new dump area, start using it
-            mDumpState = next->mDumpState != NULL ? next->mDumpState : mDummyDumpState;
-            tlNBLogWriter = next->mNBLogWriter != NULL ?
+            mDumpState = next->mDumpState != nullptr ? next->mDumpState : mDummyDumpState;
+            tlNBLogWriter = next->mNBLogWriter != nullptr ?
                     next->mNBLogWriter : mDummyNBLogWriter.get();
             setNBLogWriter(tlNBLogWriter); // This is used for debugging only
 
@@ -149,7 +145,7 @@
             mCurrent = next;
         }
 #if !LOG_NDEBUG
-        next = NULL;    // not referenced again
+        next = nullptr;    // not referenced again
 #endif
 
         mDumpState->mCommand = mCommand;
@@ -167,12 +163,12 @@
             // FIXME consider checking previous state and only perform if previous != COLD_IDLE
             if (mCurrent->mColdGen != mColdGen) {
                 int32_t *coldFutexAddr = mCurrent->mColdFutexAddr;
-                ALOG_ASSERT(coldFutexAddr != NULL);
-                int32_t old = android_atomic_dec(coldFutexAddr);
+                ALOG_ASSERT(coldFutexAddr != nullptr);
+                const int32_t old = android_atomic_dec(coldFutexAddr);
                 if (old <= 0) {
-                    syscall(__NR_futex, coldFutexAddr, FUTEX_WAIT_PRIVATE, old - 1, NULL);
+                    syscall(__NR_futex, coldFutexAddr, FUTEX_WAIT_PRIVATE, old - 1, nullptr);
                 }
-                int policy = sched_getscheduler(0) & ~SCHED_RESET_ON_FORK;
+                const int policy = sched_getscheduler(0) & ~SCHED_RESET_ON_FORK;
                 if (!(policy == SCHED_FIFO || policy == SCHED_RR)) {
                     ALOGE("did not receive expected priority boost on time");
                 }
@@ -267,7 +263,7 @@
                 mSleepNs = -1;
                 if (mIsWarm) {
                     if (sec > 0 || nsec > mUnderrunNs) {
-                        ATRACE_NAME("underrun");
+                        ATRACE_NAME("underrun");   // NOLINT(misc-const-correctness)
                         // FIXME only log occasionally
                         ALOGV("underrun: time since last cycle %d.%03ld sec",
                                 (int) sec, nsec / 1000000L);
@@ -298,7 +294,7 @@
 #ifdef FAST_THREAD_STATISTICS
                 if (mIsWarm) {
                     // advance the FIFO queue bounds
-                    size_t i = mBounds & (mDumpState->mSamplingN - 1);
+                    const size_t i = mBounds & (mDumpState->mSamplingN - 1);
                     mBounds = (mBounds & 0xFFFF0000) | ((mBounds + 1) & 0xFFFF);
                     if (mFull) {
                         //mBounds += 0x10000;
diff --git a/services/audioflinger/fastpath/FastThread.h b/services/audioflinger/fastpath/FastThread.h
index 2f0f73f..84dc4d2 100644
--- a/services/audioflinger/fastpath/FastThread.h
+++ b/services/audioflinger/fastpath/FastThread.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_AUDIO_FAST_THREAD_H
-#define ANDROID_AUDIO_FAST_THREAD_H
+#pragma once
 
 #include "Configuration.h"
 #ifdef CPU_FREQUENCY_STATISTICS
@@ -31,11 +30,10 @@
 
 public:
             FastThread(const char *cycleMs, const char *loadUs);
-    virtual ~FastThread();
 
 private:
     // implement Thread::threadLoop()
-    virtual bool threadLoop();
+    bool threadLoop() override;
 
 protected:
     // callouts to subclass in same lexical order as they were in original FastMixer.cpp
@@ -93,5 +91,3 @@
 };  // class FastThread
 
 }  // namespace android
-
-#endif  // ANDROID_AUDIO_FAST_THREAD_H
diff --git a/services/audioflinger/fastpath/FastThreadDumpState.cpp b/services/audioflinger/fastpath/FastThreadDumpState.cpp
index e91073f..09d4744 100644
--- a/services/audioflinger/fastpath/FastThreadDumpState.cpp
+++ b/services/audioflinger/fastpath/FastThreadDumpState.cpp
@@ -34,17 +34,13 @@
 #endif
 }
 
-FastThreadDumpState::~FastThreadDumpState()
-{
-}
-
 #ifdef FAST_THREAD_STATISTICS
 void FastThreadDumpState::increaseSamplingN(uint32_t samplingN)
 {
     if (samplingN <= mSamplingN || samplingN > kSamplingN || roundup(samplingN) != samplingN) {
         return;
     }
-    uint32_t additional = samplingN - mSamplingN;
+    const uint32_t additional = samplingN - mSamplingN;
     // sample arrays aren't accessed atomically with respect to the bounds,
     // so clearing reduces chance for dumpsys to read random uninitialized samples
     memset(&mMonotonicNs[mSamplingN], 0, sizeof(mMonotonicNs[0]) * additional);
diff --git a/services/audioflinger/fastpath/FastThreadDumpState.h b/services/audioflinger/fastpath/FastThreadDumpState.h
index 0b20e55..63e81d3 100644
--- a/services/audioflinger/fastpath/FastThreadDumpState.h
+++ b/services/audioflinger/fastpath/FastThreadDumpState.h
@@ -14,8 +14,9 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_AUDIO_FAST_THREAD_DUMP_STATE_H
-#define ANDROID_AUDIO_FAST_THREAD_DUMP_STATE_H
+#pragma once
+
+#include <type_traits>
 
 #include "Configuration.h"
 #include "FastThreadState.h"
@@ -30,7 +31,6 @@
 // It has a different lifetime than the FastThread, and so it can't be a member of FastThread.
 struct FastThreadDumpState {
     FastThreadDumpState();
-    /*virtual*/ ~FastThreadDumpState();
 
     FastThreadState::Command mCommand;   // current command
     uint32_t mUnderruns;        // total number of underruns
@@ -67,6 +67,7 @@
 
 };  // struct FastThreadDumpState
 
-}  // namespace android
+// No virtuals.
+static_assert(!std::is_polymorphic_v<FastThreadDumpState>);
 
-#endif  // ANDROID_AUDIO_FAST_THREAD_DUMP_STATE_H
+}  // namespace android
diff --git a/services/audioflinger/fastpath/FastThreadState.cpp b/services/audioflinger/fastpath/FastThreadState.cpp
index ad5f31f..e6cb353 100644
--- a/services/audioflinger/fastpath/FastThreadState.cpp
+++ b/services/audioflinger/fastpath/FastThreadState.cpp
@@ -20,12 +20,8 @@
 namespace android {
 
 FastThreadState::FastThreadState() :
-    mCommand(INITIAL), mColdFutexAddr(NULL), mColdGen(0), mDumpState(NULL), mNBLogWriter(NULL)
-
-{
-}
-
-FastThreadState::~FastThreadState()
+    mCommand(INITIAL), mColdFutexAddr(nullptr), mColdGen(0), mDumpState(nullptr)
+    , mNBLogWriter(nullptr)
 {
 }
 
@@ -38,7 +34,7 @@
     case FastThreadState::COLD_IDLE:    return "COLD_IDLE";
     case FastThreadState::EXIT:         return "EXIT";
     }
-    return NULL;
+    return nullptr;
 }
 
 }   // namespace android
diff --git a/services/audioflinger/fastpath/FastThreadState.h b/services/audioflinger/fastpath/FastThreadState.h
index 9fb4e06..2b8b079 100644
--- a/services/audioflinger/fastpath/FastThreadState.h
+++ b/services/audioflinger/fastpath/FastThreadState.h
@@ -14,9 +14,9 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_AUDIO_FAST_THREAD_STATE_H
-#define ANDROID_AUDIO_FAST_THREAD_STATE_H
+#pragma once
 
+#include <type_traits>
 #include "Configuration.h"
 #include <stdint.h>
 #include <media/nblog/NBLog.h>
@@ -28,9 +28,8 @@
 // Represents a single state of a FastThread
 struct FastThreadState {
                 FastThreadState();
-    /*virtual*/ ~FastThreadState();
 
-    typedef uint32_t Command;
+    using Command = uint32_t;
     static const Command
         INITIAL = 0,            // used only for the initial state
         HOT_IDLE = 1,           // do nothing
@@ -50,6 +49,7 @@
     static const char *commandToString(Command command);
 };  // struct FastThreadState
 
-}  // namespace android
+// No virtuals.
+static_assert(!std::is_polymorphic_v<FastThreadState>);
 
-#endif  // ANDROID_AUDIO_FAST_THREAD_STATE_H
+}  // namespace android
diff --git a/services/audioflinger/fastpath/StateQueue.cpp b/services/audioflinger/fastpath/StateQueue.cpp
index 38ce2c2..c466b9f 100644
--- a/services/audioflinger/fastpath/StateQueue.cpp
+++ b/services/audioflinger/fastpath/StateQueue.cpp
@@ -41,8 +41,8 @@
 // Constructor and destructor
 
 template<typename T> StateQueue<T>::StateQueue() :
-    mAck(NULL), mCurrent(NULL),
-    mMutating(&mStates[0]), mExpecting(NULL),
+    mAck(nullptr), mCurrent(nullptr),
+    mMutating(&mStates[0]), mExpecting(nullptr),
     mInMutation(false), mIsDirty(false), mIsInitialized(false)
 #ifdef STATE_QUEUE_DUMP
     , mObserverDump(&mObserverDummyDump), mMutatorDump(&mMutatorDummyDump)
@@ -51,10 +51,6 @@
     atomic_init(&mNext, static_cast<uintptr_t>(0));
 }
 
-template<typename T> StateQueue<T>::~StateQueue()
-{
-}
-
 // Observer APIs
 
 template<typename T> const T* StateQueue<T>::poll()
@@ -112,7 +108,7 @@
 #endif
 
         // wait for prior push to be acknowledged
-        if (mExpecting != NULL) {
+        if (mExpecting != nullptr) {
 #ifdef STATE_QUEUE_DUMP
             unsigned count = 0;
 #endif
@@ -120,7 +116,7 @@
                 const T *ack = (const T *) mAck;    // no additional barrier needed
                 if (ack == mExpecting) {
                     // unnecessary as we're about to rewrite
-                    //mExpecting = NULL;
+                    //mExpecting = nullptr;
                     break;
                 }
                 if (block == BLOCK_NEVER) {
@@ -132,7 +128,7 @@
                 }
                 ++count;
 #endif
-                nanosleep(&req, NULL);
+                nanosleep(&req, nullptr);
             }
 #ifdef STATE_QUEUE_DUMP
             if (count > 1) {
@@ -156,14 +152,14 @@
 
     // optionally wait for this push or a prior push to be acknowledged
     if (block == BLOCK_UNTIL_ACKED) {
-        if (mExpecting != NULL) {
+        if (mExpecting != nullptr) {
 #ifdef STATE_QUEUE_DUMP
             unsigned count = 0;
 #endif
             for (;;) {
                 const T *ack = (const T *) mAck;    // no additional barrier needed
                 if (ack == mExpecting) {
-                    mExpecting = NULL;
+                    mExpecting = nullptr;
                     break;
                 }
 #ifdef STATE_QUEUE_DUMP
@@ -172,7 +168,7 @@
                 }
                 ++count;
 #endif
-                nanosleep(&req, NULL);
+                nanosleep(&req, nullptr);
             }
 #ifdef STATE_QUEUE_DUMP
             if (count > 1) {
diff --git a/services/audioflinger/fastpath/StateQueue.h b/services/audioflinger/fastpath/StateQueue.h
index 27f6a28..dff8f3f 100644
--- a/services/audioflinger/fastpath/StateQueue.h
+++ b/services/audioflinger/fastpath/StateQueue.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_AUDIO_STATE_QUEUE_H
-#define ANDROID_AUDIO_STATE_QUEUE_H
+#pragma once
 
 #include <stdatomic.h>
 
@@ -128,7 +127,7 @@
 
 public:
             StateQueue();
-    virtual ~StateQueue();
+    virtual ~StateQueue() = default;  // why is this virtual?
 
     // Observer APIs
 
@@ -211,5 +210,3 @@
 };  // class StateQueue
 
 }   // namespace android
-
-#endif  // ANDROID_AUDIO_STATE_QUEUE_H