diff --git a/Android.bp b/Android.bp
new file mode 100644
index 0000000..6fd6c72
--- /dev/null
+++ b/Android.bp
@@ -0,0 +1,4 @@
+subdirs = [
+    "media/libmedia",
+    "media/libstagefright/foundation",
+]
diff --git a/media/libmedia/Android.bp b/media/libmedia/Android.bp
new file mode 100644
index 0000000..7fde4b2
--- /dev/null
+++ b/media/libmedia/Android.bp
@@ -0,0 +1,10 @@
+cc_library_static {
+    name: "libmedia_helper",
+    srcs: ["AudioParameter.cpp"],
+    cflags: [
+        "-Werror",
+        "-Wno-error=deprecated-declarations",
+        "-Wall",
+    ],
+    clang: true,
+}
diff --git a/media/libmedia/Android.mk b/media/libmedia/Android.mk
index 1b92123..202b5f8 100644
--- a/media/libmedia/Android.mk
+++ b/media/libmedia/Android.mk
@@ -3,18 +3,6 @@
 include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES:= \
-    AudioParameter.cpp
-LOCAL_MODULE:= libmedia_helper
-LOCAL_MODULE_TAGS := optional
-
-LOCAL_CFLAGS += -Werror -Wno-error=deprecated-declarations -Wall
-LOCAL_CLANG := true
-
-include $(BUILD_STATIC_LIBRARY)
-
-include $(CLEAR_VARS)
-
-LOCAL_SRC_FILES:= \
     AudioTrack.cpp \
     AudioTrackShared.cpp \
     IAudioFlinger.cpp \
diff --git a/media/libmediaplayerservice/nuplayer/GenericSource.h b/media/libmediaplayerservice/nuplayer/GenericSource.h
index 9fe49af..0957778 100644
--- a/media/libmediaplayerservice/nuplayer/GenericSource.h
+++ b/media/libmediaplayerservice/nuplayer/GenericSource.h
@@ -117,7 +117,7 @@
     // When necessary, it will send out buffering events to the player.
     struct BufferingMonitor : public AHandler {
     public:
-        BufferingMonitor(const sp<AMessage> &notify);
+        explicit BufferingMonitor(const sp<AMessage> &notify);
 
         // Set up state.
         void prepare(const sp<NuCachedSource2> &cachedSource,
diff --git a/media/libstagefright/foundation/Android.bp b/media/libstagefright/foundation/Android.bp
new file mode 100644
index 0000000..f7bd3f2
--- /dev/null
+++ b/media/libstagefright/foundation/Android.bp
@@ -0,0 +1,51 @@
+cc_library_shared {
+    name: "libstagefright_foundation",
+
+    srcs: [
+        "AAtomizer.cpp",
+        "ABitReader.cpp",
+        "ABuffer.cpp",
+        "ADebug.cpp",
+        "AHandler.cpp",
+        "AHierarchicalStateMachine.cpp",
+        "ALooper.cpp",
+        "ALooperRoster.cpp",
+        "AMessage.cpp",
+        "ANetworkSession.cpp",
+        "AString.cpp",
+        "AStringUtils.cpp",
+        "AWakeLock.cpp",
+        "ColorUtils.cpp",
+        "MediaBuffer.cpp",
+        "MediaBufferGroup.cpp",
+        "MetaData.cpp",
+        "ParsedMessage.cpp",
+        "base64.cpp",
+        "hexdump.cpp",
+    ],
+
+    include_dirs: ["frameworks/av/include/media/stagefright/foundation"],
+
+    shared_libs: [
+        "libbinder",
+        "libutils",
+        "libcutils",
+        "liblog",
+        "libpowermanager",
+    ],
+
+    export_shared_lib_headers: ["libbinder"],
+
+    cflags: [
+        "-Wno-multichar",
+        "-Werror",
+        "-Wall",
+    ],
+    clang: true,
+    sanitize: {
+        misc_undefined: [
+            "unsigned-integer-overflow",
+            "signed-integer-overflow",
+        ],
+    },
+}
diff --git a/media/libstagefright/foundation/Android.mk b/media/libstagefright/foundation/Android.mk
deleted file mode 100644
index b977c65..0000000
--- a/media/libstagefright/foundation/Android.mk
+++ /dev/null
@@ -1,46 +0,0 @@
-LOCAL_PATH:= $(call my-dir)
-include $(CLEAR_VARS)
-
-LOCAL_SRC_FILES:=                 \
-    AAtomizer.cpp                 \
-    ABitReader.cpp                \
-    ABuffer.cpp                   \
-    ADebug.cpp                    \
-    AHandler.cpp                  \
-    AHierarchicalStateMachine.cpp \
-    ALooper.cpp                   \
-    ALooperRoster.cpp             \
-    AMessage.cpp                  \
-    ANetworkSession.cpp           \
-    AString.cpp                   \
-    AStringUtils.cpp              \
-    AWakeLock.cpp                 \
-    ColorUtils.cpp                \
-    MediaBuffer.cpp               \
-    MediaBufferGroup.cpp          \
-    MetaData.cpp                  \
-    ParsedMessage.cpp             \
-    base64.cpp                    \
-    hexdump.cpp
-
-LOCAL_C_INCLUDES:= \
-    frameworks/av/include/media/stagefright/foundation
-
-LOCAL_SHARED_LIBRARIES := \
-        libbinder         \
-        libutils          \
-        libcutils         \
-        liblog            \
-        libpowermanager
-
-LOCAL_EXPORT_SHARED_LIBRARY_HEADERS := libbinder
-
-LOCAL_CFLAGS += -Wno-multichar -Werror -Wall
-LOCAL_CLANG := true
-LOCAL_SANITIZE := unsigned-integer-overflow signed-integer-overflow
-
-LOCAL_MODULE:= libstagefright_foundation
-
-
-
-include $(BUILD_SHARED_LIBRARY)
diff --git a/media/ndk/NdkImageReaderPriv.h b/media/ndk/NdkImageReaderPriv.h
index 48f0953..8b540fa 100644
--- a/media/ndk/NdkImageReaderPriv.h
+++ b/media/ndk/NdkImageReaderPriv.h
@@ -112,7 +112,7 @@
 
     struct FrameListener : public ConsumerBase::FrameAvailableListener {
       public:
-        FrameListener(AImageReader* parent) : mReader(parent) {}
+        explicit FrameListener(AImageReader* parent) : mReader(parent) {}
 
         void onFrameAvailable(const BufferItem& item) override;
 
diff --git a/services/audioflinger/AutoPark.h b/services/audioflinger/AutoPark.h
index e539e47..9ac7b65 100644
--- a/services/audioflinger/AutoPark.h
+++ b/services/audioflinger/AutoPark.h
@@ -21,7 +21,7 @@
 public:
 
     // Park the specific FastThread, which can be nullptr, in hot idle if not currently idling
-    AutoPark(const sp<T>& fastThread) : mFastThread(fastThread)
+    explicit AutoPark(const sp<T>& fastThread) : mFastThread(fastThread)
     {
         mPreviousCommand = FastThreadState::HOT_IDLE;
         if (fastThread != nullptr) {
diff --git a/services/audioflinger/LinearMap.h b/services/audioflinger/LinearMap.h
index fca14dd..2220a0c 100644
--- a/services/audioflinger/LinearMap.h
+++ b/services/audioflinger/LinearMap.h
@@ -134,7 +134,7 @@
         FIND_METHOD_START_VALUE,             // No samples in history, using start value
     };
 
-    LinearMap(size_t size)
+    explicit LinearMap(size_t size)
             : mSize(size),
               mPos(0), // a circular buffer, so could start anywhere. the first sample is at 1.
               mSamples(0),
diff --git a/services/audiopolicy/common/managerdefinitions/include/AudioRoute.h b/services/audiopolicy/common/managerdefinitions/include/AudioRoute.h
index 67e197f..df54f48 100644
--- a/services/audiopolicy/common/managerdefinitions/include/AudioRoute.h
+++ b/services/audiopolicy/common/managerdefinitions/include/AudioRoute.h
@@ -36,7 +36,7 @@
 class AudioRoute  : public virtual RefBase
 {
 public:
-    AudioRoute(audio_route_type_t type) : mType(type) {}
+    explicit AudioRoute(audio_route_type_t type) : mType(type) {}
 
     void setSources(const AudioPortVector &sources) { mSources = sources; }
     const AudioPortVector &getSources() const { return mSources; }
diff --git a/services/audiopolicy/common/managerdefinitions/include/IOProfile.h b/services/audiopolicy/common/managerdefinitions/include/IOProfile.h
index e3ad44d..ec04ef7 100644
--- a/services/audiopolicy/common/managerdefinitions/include/IOProfile.h
+++ b/services/audiopolicy/common/managerdefinitions/include/IOProfile.h
@@ -110,13 +110,13 @@
 class InputProfile : public IOProfile
 {
 public:
-    InputProfile(const String8 &name) : IOProfile(name, AUDIO_PORT_ROLE_SINK) {}
+    explicit InputProfile(const String8 &name) : IOProfile(name, AUDIO_PORT_ROLE_SINK) {}
 };
 
 class OutputProfile : public IOProfile
 {
 public:
-    OutputProfile(const String8 &name) : IOProfile(name, AUDIO_PORT_ROLE_SOURCE) {}
+    explicit OutputProfile(const String8 &name) : IOProfile(name, AUDIO_PORT_ROLE_SOURCE) {}
 };
 
 }; // namespace android
diff --git a/services/audiopolicy/service/AudioPolicyClientImplLegacy.cpp b/services/audiopolicy/service/AudioPolicyClientImplLegacy.cpp
index 151d066..dabffe6 100644
--- a/services/audiopolicy/service/AudioPolicyClientImplLegacy.cpp
+++ b/services/audiopolicy/service/AudioPolicyClientImplLegacy.cpp
@@ -56,7 +56,7 @@
     sp<IAudioFlinger> af = AudioSystem::get_audio_flinger();
     if (af == 0) {
         ALOGW("%s: could not get AudioFlinger", __func__);
-        return 0;
+        return AUDIO_MODULE_HANDLE_NONE;
     }
 
     return af->loadHwModule(name);