Add compile-time checks for libandroid_runtime

Before this CL, libandroid_runtime didn't process thread-safety
annotations and didn't enforce the -Wextra checks.

Add those here, along with the required fixes.

Bug: 271455682
Test: m libandroid_runtime
Change-Id: Ibff26167ea142150a461c54ec631b70b6d0d15e5
diff --git a/core/jni/Android.bp b/core/jni/Android.bp
index 3795fc8..440a332 100644
--- a/core/jni/Android.bp
+++ b/core/jni/Android.bp
@@ -43,7 +43,10 @@
 
         "-Wall",
         "-Werror",
+        "-Wextra",
+        "-Wthread-safety",
         "-Wno-error=deprecated-declarations",
+        "-Wno-unused-parameter",
         "-Wunused",
         "-Wunreachable-code",
 
diff --git a/core/jni/android_content_res_ResourceTimer.cpp b/core/jni/android_content_res_ResourceTimer.cpp
index 91e3c921..66bda61 100644
--- a/core/jni/android_content_res_ResourceTimer.cpp
+++ b/core/jni/android_content_res_ResourceTimer.cpp
@@ -44,9 +44,9 @@
 
 static int NativeGetTimers(JNIEnv* env, jobject /*clazz*/, jobjectArray timer, jboolean reset) {
   size_t size = ResourceTimer::counterSize;
-  if (jsize st = env->GetArrayLength(timer); st < size) {
-    // Shrink the size to the minimum of the available counters and the available space.
-    size = st;
+  if (size_t st = env->GetArrayLength(timer); st < size) {
+      // Shrink the size to the minimum of the available counters and the available space.
+      size = st;
   }
   for (size_t i = 0; i < size; i++) {
     ResourceTimer::Timer src;
diff --git a/core/jni/android_hardware_camera2_DngCreator.cpp b/core/jni/android_hardware_camera2_DngCreator.cpp
index 30e546c..82570be8 100644
--- a/core/jni/android_hardware_camera2_DngCreator.cpp
+++ b/core/jni/android_hardware_camera2_DngCreator.cpp
@@ -1892,8 +1892,8 @@
         camera_metadata_entry entry =
             results.find(ANDROID_SENSOR_NOISE_PROFILE);
 
-        const status_t numPlaneColors = isBayer ? 3 : 1;
-        const status_t numCfaChannels = isBayer ? 4 : 1;
+        const unsigned long numPlaneColors = isBayer ? 3 : 1;
+        const unsigned long numCfaChannels = isBayer ? 4 : 1;
 
         uint8_t cfaOut[numCfaChannels];
         if ((err = convertCFA(cfaEnum, /*out*/cfaOut)) != OK) {
diff --git a/core/jni/android_hardware_camera2_impl_CameraExtensionJpegProcessor.cpp b/core/jni/android_hardware_camera2_impl_CameraExtensionJpegProcessor.cpp
index 1390759..4bde87f 100644
--- a/core/jni/android_hardware_camera2_impl_CameraExtensionJpegProcessor.cpp
+++ b/core/jni/android_hardware_camera2_impl_CameraExtensionJpegProcessor.cpp
@@ -599,7 +599,7 @@
             quality, cropLeft, cropTop, cropRight, cropBottom, rot90);
 
     size_t finalJpegSize = actualJpegSize + sizeof(CameraBlob);
-    if (finalJpegSize > outBufCapacity) {
+    if (finalJpegSize > static_cast<size_t>(outBufCapacity)) {
         ALOGE("%s: Final jpeg buffer %zu not large enough for the jpeg blob header with "\
                 "capacity %d", __FUNCTION__, finalJpegSize, outBufCapacity);
         return actualJpegSize;
diff --git a/core/jni/android_media_AudioProductStrategies.cpp b/core/jni/android_media_AudioProductStrategies.cpp
index 4b563d7..7c9dae0 100644
--- a/core/jni/android_media_AudioProductStrategies.cpp
+++ b/core/jni/android_media_AudioProductStrategies.cpp
@@ -88,12 +88,12 @@
     int attrGroupIndex = 0;
     std::map<int /**attributesGroupIndex*/, std::vector<VolumeGroupAttributes> > groups;
     for (const auto &attr : strategy.getVolumeGroupAttributes()) {
-        int groupId = attr.getGroupId();
+        auto groupId = attr.getGroupId();
         int streamType = attr.getStreamType();
         const auto &iter = std::find_if(begin(groups), end(groups),
                                         [groupId, streamType](const auto &iter) {
             const auto &frontAttr = iter.second.front();
-            return frontAttr.getGroupId() == groupId && frontAttr.getStreamType() == streamType;
+            return (frontAttr.getGroupId() == groupId && frontAttr.getStreamType() == streamType);
         });
         // Same Volume Group Id and same stream type
         if (iter != end(groups)) {
diff --git a/core/jni/android_media_AudioSystem.cpp b/core/jni/android_media_AudioSystem.cpp
index 6440cc3..3413ede 100644
--- a/core/jni/android_media_AudioSystem.cpp
+++ b/core/jni/android_media_AudioSystem.cpp
@@ -2501,7 +2501,7 @@
             int *nativeArray = nullptr;
             nativeArray = env->GetIntArrayElements(jArray, 0);
             if (nativeArray != nullptr) {
-                for (size_t i = 0; i < len; i++) {
+                for (size_t i = 0; i < static_cast<size_t>(len); i++) {
                     nativeVector.push_back(nativeArray[i]);
                 }
                 env->ReleaseIntArrayElements(jArray, nativeArray, 0);
@@ -2565,7 +2565,7 @@
 
     if (nativeSystemUsages != nullptr) {
         jsize len = env->GetArrayLength(systemUsages);
-        for (size_t i = 0; i < len; i++) {
+        for (size_t i = 0; i < static_cast<size_t>(len); i++) {
             audio_usage_t nativeAudioUsage =
                     static_cast<audio_usage_t>(nativeSystemUsages[i]);
             nativeSystemUsagesVector.push_back(nativeAudioUsage);
@@ -2776,7 +2776,7 @@
         return jStatus;
     }
 
-    if (devices.size() > maxResultSize) {
+    if (devices.size() > static_cast<size_t>(maxResultSize)) {
         return AUDIO_JAVA_INVALID_OPERATION;
     }
     size_t index = 0;
diff --git a/core/jni/android_net_LocalSocketImpl.cpp b/core/jni/android_net_LocalSocketImpl.cpp
index 9bd0700..47b4a46 100644
--- a/core/jni/android_net_LocalSocketImpl.cpp
+++ b/core/jni/android_net_LocalSocketImpl.cpp
@@ -221,7 +221,7 @@
 
     ssize_t rc = SendFileDescriptorVector(fd, buffer, len, fds);
 
-    while (rc != len) {
+    while (rc != static_cast<ssize_t>(len)) {
         if (rc == -1) {
             jniThrowIOException(env, errno);
             return -1;
diff --git a/core/jni/android_os_HwBlob.cpp b/core/jni/android_os_HwBlob.cpp
index a9db91b..e554b44 100644
--- a/core/jni/android_os_HwBlob.cpp
+++ b/core/jni/android_os_HwBlob.cpp
@@ -265,7 +265,7 @@
     //   justify passing such a large amount of data over this path. So the
     //   alternative (updating the constructor and other code to accept other
     //   types, should also probably not be taken in this case).
-    CHECK_LE(size, std::numeric_limits<jint>::max());
+    CHECK_LE(size, static_cast<size_t>(std::numeric_limits<jint>::max()));
 
     return env->NewObject(clazz.get(), constructID, static_cast<jint>(size));
 }
diff --git a/core/jni/android_os_Parcel.cpp b/core/jni/android_os_Parcel.cpp
index 4d8dac1..3539476 100644
--- a/core/jni/android_os_Parcel.cpp
+++ b/core/jni/android_os_Parcel.cpp
@@ -691,7 +691,7 @@
 
 // String tries to allocate itself on the stack, within a known size, but will
 // make a heap allocation if not.
-template <size_t StackReserve>
+template <jsize StackReserve>
 class StackString {
 public:
     StackString(JNIEnv* env, jstring str) : mEnv(env), mJStr(str) {
diff --git a/core/jni/android_os_PerformanceHintManager.cpp b/core/jni/android_os_PerformanceHintManager.cpp
index 27c4cd4..95bf49f 100644
--- a/core/jni/android_os_PerformanceHintManager.cpp
+++ b/core/jni/android_os_PerformanceHintManager.cpp
@@ -224,7 +224,7 @@
         return nullptr;
     }
     jint* threadIds = env->GetIntArrayElements(jintArr, 0);
-    for (int i = 0; i < size; ++i) {
+    for (size_t i = 0; i < size; ++i) {
         threadIds[i] = tidsVector[i];
     }
     env->ReleaseIntArrayElements(jintArr, threadIds, 0);
diff --git a/core/jni/android_util_CharsetUtils.cpp b/core/jni/android_util_CharsetUtils.cpp
index 7ab6e8f2..7071cf2 100644
--- a/core/jni/android_util_CharsetUtils.cpp
+++ b/core/jni/android_util_CharsetUtils.cpp
@@ -25,7 +25,7 @@
 
     // Quickly check if destination has plenty of room for worst-case
     // 4-bytes-per-char encoded size
-    const size_t worstLen = (srcLen * 4);
+    const jint worstLen = (srcLen * 4);
     if (destOff >= 0 && destOff + worstLen < destLen) {
         env->GetStringUTFRegion(src, 0, srcLen, destPtr + destOff);
         return strlen(destPtr + destOff + srcLen) + srcLen;
@@ -33,7 +33,7 @@
 
     // String still might fit in destination, but we need to measure
     // its actual encoded size to be sure
-    const size_t encodedLen = env->GetStringUTFLength(src);
+    const jint encodedLen = env->GetStringUTFLength(src);
     if (destOff >= 0 && destOff + encodedLen < destLen) {
         env->GetStringUTFRegion(src, 0, srcLen, destPtr + destOff);
         return encodedLen;
diff --git a/core/jni/android_util_FileObserver.cpp b/core/jni/android_util_FileObserver.cpp
index c64c212..8d3da7b 100644
--- a/core/jni/android_util_FileObserver.cpp
+++ b/core/jni/android_util_FileObserver.cpp
@@ -114,7 +114,7 @@
     if (fd >= 0)
     {
         size_t count = wfds.size();
-        for (jsize i = 0; i < count; ++i) {
+        for (size_t i = 0; i < count; ++i) {
             jstring pathString = (jstring) env->GetObjectArrayElement(pathStrings, i);
 
             ScopedUtfChars path(env, pathString);
diff --git a/core/jni/android_view_DisplayEventReceiver.cpp b/core/jni/android_view_DisplayEventReceiver.cpp
index 41c65ae..fef8ad7 100644
--- a/core/jni/android_view_DisplayEventReceiver.cpp
+++ b/core/jni/android_view_DisplayEventReceiver.cpp
@@ -140,7 +140,7 @@
         env->ExceptionClear();
         return NULL;
     }
-    for (int i = 0; i < vsyncEventData.frameTimelinesLength; i++) {
+    for (size_t i = 0; i < vsyncEventData.frameTimelinesLength; i++) {
         VsyncEventData::FrameTimeline frameTimeline = vsyncEventData.frameTimelines[i];
         ScopedLocalRef<jobject>
                 frameTimelineObj(env,
@@ -193,7 +193,7 @@
                                                               gDisplayEventReceiverClassInfo
                                                                       .vsyncEventDataClassInfo
                                                                       .frameTimelines)));
-        for (int i = 0; i < vsyncEventData.frameTimelinesLength; i++) {
+        for (size_t i = 0; i < vsyncEventData.frameTimelinesLength; i++) {
             VsyncEventData::FrameTimeline& frameTimeline = vsyncEventData.frameTimelines[i];
             ScopedLocalRef<jobject>
                     frameTimelineObj(env, env->GetObjectArrayElement(frameTimelinesObj.get(), i));
diff --git a/core/jni/android_view_SurfaceControl.cpp b/core/jni/android_view_SurfaceControl.cpp
index 9833598..a800e6e 100644
--- a/core/jni/android_view_SurfaceControl.cpp
+++ b/core/jni/android_view_SurfaceControl.cpp
@@ -1950,7 +1950,7 @@
 
         jobjectArray jJankDataArray = env->NewObjectArray(jankData.size(),
                 gJankDataClassInfo.clazz, nullptr);
-        for (int i = 0; i < jankData.size(); i++) {
+        for (size_t i = 0; i < jankData.size(); i++) {
             jobject jJankData = env->NewObject(gJankDataClassInfo.clazz,
                     gJankDataClassInfo.ctor, jankData[i].frameVsyncId, jankData[i].jankType);
             env->SetObjectArrayElement(jJankDataArray, i, jJankData);
diff --git a/core/jni/android_window_WindowInfosListener.cpp b/core/jni/android_window_WindowInfosListener.cpp
index 55995df..bc69d1e6 100644
--- a/core/jni/android_window_WindowInfosListener.cpp
+++ b/core/jni/android_window_WindowInfosListener.cpp
@@ -67,7 +67,7 @@
 static jobjectArray fromWindowInfos(JNIEnv* env, const std::vector<WindowInfo>& windowInfos) {
     jobjectArray jWindowHandlesArray =
             env->NewObjectArray(windowInfos.size(), gInputWindowHandleClass, nullptr);
-    for (int i = 0; i < windowInfos.size(); i++) {
+    for (size_t i = 0; i < windowInfos.size(); i++) {
         ScopedLocalRef<jobject>
                 jWindowHandle(env,
                               android_view_InputWindowHandle_fromWindowInfo(env, windowInfos[i]));
@@ -80,7 +80,7 @@
 static jobjectArray fromDisplayInfos(JNIEnv* env, const std::vector<DisplayInfo>& displayInfos) {
     jobjectArray jDisplayInfoArray =
             env->NewObjectArray(displayInfos.size(), gDisplayInfoClassInfo.clazz, nullptr);
-    for (int i = 0; i < displayInfos.size(); i++) {
+    for (size_t i = 0; i < displayInfos.size(); i++) {
         ScopedLocalRef<jobject> jDisplayInfo(env, fromDisplayInfo(env, displayInfos[i]));
         env->SetObjectArrayElement(jDisplayInfoArray, i, jDisplayInfo.get());
     }
diff --git a/core/jni/com_android_internal_content_om_OverlayManagerImpl.cpp b/core/jni/com_android_internal_content_om_OverlayManagerImpl.cpp
index d4f6e18..0c39a69 100644
--- a/core/jni/com_android_internal_content_om_OverlayManagerImpl.cpp
+++ b/core/jni/com_android_internal_content_om_OverlayManagerImpl.cpp
@@ -266,11 +266,11 @@
         auto jsResourceName = reinterpret_cast<jstring>(
                 env->GetObjectField(entry, gFabricatedOverlayInternalEntryOffsets.resourceName));
         const ScopedUtfChars resourceName(env, jsResourceName);
-        const auto dataType =
+        const jint dataType =
                 env->GetIntField(entry, gFabricatedOverlayInternalEntryOffsets.dataType);
 
         // In Java, the data type is int but the maximum value of data Type is less than 0xff.
-        if (dataType >= UCHAR_MAX) {
+        if (dataType >= static_cast<jint>(UCHAR_MAX)) {
             jniThrowException(env, IllegalArgumentException, "Unsupported data type");
             return;
         }
diff --git a/core/jni/com_android_internal_os_KernelCpuUidBpfMapReader.cpp b/core/jni/com_android_internal_os_KernelCpuUidBpfMapReader.cpp
index 098a4d8..cf70c90 100644
--- a/core/jni/com_android_internal_os_KernelCpuUidBpfMapReader.cpp
+++ b/core/jni/com_android_internal_os_KernelCpuUidBpfMapReader.cpp
@@ -55,7 +55,7 @@
 
 static jboolean KernelCpuUidFreqTimeBpfMapReader_removeUidRange(JNIEnv *env, jclass, jint startUid,
                                                                 jint endUid) {
-    for (uint32_t uid = startUid; uid <= endUid; ++uid) {
+    for (jint uid = startUid; uid <= endUid; ++uid) {
         if (!android::bpf::clearUidTimes(uid)) return false;
     }
     return true;
diff --git a/core/jni/com_android_internal_os_KernelSingleProcessCpuThreadReader.cpp b/core/jni/com_android_internal_os_KernelSingleProcessCpuThreadReader.cpp
index dfae684..be9013b 100644
--- a/core/jni/com_android_internal_os_KernelSingleProcessCpuThreadReader.cpp
+++ b/core/jni/com_android_internal_os_KernelSingleProcessCpuThreadReader.cpp
@@ -147,7 +147,7 @@
     std::unique_ptr<ICpuTimeInStateReader> cpuTimeInStateReader(
             getCpuTimeInStateReader(env, cpuTimeInStateReaderObject));
 
-    for (int i = 0; i < selectedThreadIds.size(); i++) {
+    for (size_t i = 0; i < selectedThreadIds.size(); i++) {
         if (!cpuTimeInStateReader->startAggregatingTaskCpuTimes(selectedThreadIds[i],
                                                                 SELECTED_THREAD_AGGREGATION_KEY)) {
             return false;
@@ -312,11 +312,11 @@
         auto fields = android::base::Split(line.c_str(), ":");
         android::base::ParseUint(fields[0], &aggregationKey);
 
-        for (int j = 1; j < fields.size(); j++) {
+        for (size_t j = 1; j < fields.size(); j++) {
             auto numbers = android::base::Split(fields[j], " ");
 
             std::vector<uint64_t> chunk;
-            for (int k = 0; k < numbers.size(); k++) {
+            for (size_t k = 0; k < numbers.size(); k++) {
                 uint64_t time;
                 android::base::ParseUint(numbers[k], &time);
                 chunk.emplace_back(time);
diff --git a/core/jni/com_android_internal_os_LongArrayMultiStateCounter.cpp b/core/jni/com_android_internal_os_LongArrayMultiStateCounter.cpp
index 1f29735..dab47e9 100644
--- a/core/jni/com_android_internal_os_LongArrayMultiStateCounter.cpp
+++ b/core/jni/com_android_internal_os_LongArrayMultiStateCounter.cpp
@@ -288,7 +288,7 @@
     }
 
     bool nonZero = false;
-    for (int i = 0; i < vector->size(); i++) {
+    for (size_t i = 0; i < vector->size(); i++) {
         jint index = scopedIndexMap[i];
         if (index < 0 || index >= size) {
             jniThrowExceptionFmt(env, "java/lang/IndexOutOfBoundsException",
diff --git a/core/jni/com_android_internal_os_Zygote.cpp b/core/jni/com_android_internal_os_Zygote.cpp
index 9c1bea7..7c5885a 100644
--- a/core/jni/com_android_internal_os_Zygote.cpp
+++ b/core/jni/com_android_internal_os_Zygote.cpp
@@ -1094,8 +1094,8 @@
       }
       struct dirent* ent;
       while ((ent = readdir(dir.get()))) {
-        if (ent->d_ino == ce_data_inode) {
-          return ent->d_name;
+        if (static_cast<long long>(ent->d_ino) == ce_data_inode) {
+            return ent->d_name;
         }
       }
     }
@@ -1765,14 +1765,14 @@
 static void ReloadBuildJavaConstants(JNIEnv* env) {
   jclass build_cls = env->FindClass("android/os/Build");
   size_t arr_size = sizeof(build_constants) / sizeof(build_constants[0]);
-  for (int i = 0; i < arr_size; i++) {
+  for (size_t i = 0; i < arr_size; i++) {
     const char* field_name = build_constants[i].first;
     const char* sysprop_name = build_constants[i].second;
     ReloadBuildJavaConstant(env, build_cls, field_name, "Ljava/lang/String;", sysprop_name);
   }
   jclass build_version_cls = env->FindClass("android/os/Build$VERSION");
   arr_size = sizeof(build_version_constants) / sizeof(build_version_constants[0]);
-  for (int i = 0; i < arr_size; i++) {
+  for (size_t i = 0; i < arr_size; i++) {
     const char* field_name = build_version_constants[i].first;
     const char* sysprop_name = build_version_constants[i].second;
     ReloadBuildJavaConstant(env, build_version_cls, field_name, "Ljava/lang/String;", sysprop_name);
@@ -2901,7 +2901,7 @@
         return -1;
     }
     ScopedByteArrayRO source(env, in);
-    if (source.size() < length) {
+    if (source.size() < static_cast<size_t>(length)) {
         // Invalid parameter
         jniThrowException(env, "java/lang/IllegalArgumentException", nullptr);
         return -1;
diff --git a/core/jni/com_android_internal_os_ZygoteCommandBuffer.cpp b/core/jni/com_android_internal_os_ZygoteCommandBuffer.cpp
index 2b5b8f7..87ab496 100644
--- a/core/jni/com_android_internal_os_ZygoteCommandBuffer.cpp
+++ b/core/jni/com_android_internal_os_ZygoteCommandBuffer.cpp
@@ -76,7 +76,7 @@
             return {};
           }
           fail_fn(CREATE_ERROR("session socket read failed: %s", strerror(errno)));
-        } else if (nread == MAX_COMMAND_BYTES - mEnd) {
+        } else if (nread == static_cast<ssize_t>(MAX_COMMAND_BYTES - mEnd)) {
           // This is pessimistic by one character, but close enough.
           fail_fn("ZygoteCommandBuffer overflowed: command too long");
         }
@@ -136,7 +136,7 @@
     }
     char* countString = line.value().first;  // Newline terminated.
     long nArgs = atol(countString);
-    if (nArgs <= 0 || nArgs >= MAX_COMMAND_BYTES / 2) {
+    if (nArgs <= 0 || nArgs >= static_cast<long>(MAX_COMMAND_BYTES / 2)) {
       fail_fn(CREATE_ERROR("Unreasonable argument count %ld", nArgs));
     }
     mLinesLeft = nArgs;
@@ -153,7 +153,7 @@
   // As a side effect, this sets mNiceName to a non-empty string, if possible.
   template<class FailFn>
   bool isSimpleForkCommand(int minUid, FailFn fail_fn) {
-    if (mLinesLeft <= 0 || mLinesLeft  >= MAX_COMMAND_BYTES / 2) {
+    if (mLinesLeft <= 0 || mLinesLeft >= static_cast<int32_t>(MAX_COMMAND_BYTES / 2)) {
       return false;
     }
     static const char* RUNTIME_ARGS = "--runtime-args";
@@ -179,14 +179,14 @@
       if (!read_result.has_value()) {
         return false;
       }
-      auto [arg_start, arg_end] = read_result.value();
-      if (arg_end - arg_start == RA_LENGTH
-          && strncmp(arg_start, RUNTIME_ARGS, RA_LENGTH) == 0) {
+      const auto [arg_start, arg_end] = read_result.value();
+      if (static_cast<size_t>(arg_end - arg_start) == RA_LENGTH &&
+          strncmp(arg_start, RUNTIME_ARGS, RA_LENGTH) == 0) {
         saw_runtime_args = true;
         continue;
       }
-      if (arg_end - arg_start >= NN_LENGTH
-          && strncmp(arg_start, NICE_NAME, NN_LENGTH) == 0) {
+      if (static_cast<size_t>(arg_end - arg_start) >= NN_LENGTH &&
+          strncmp(arg_start, NICE_NAME, NN_LENGTH) == 0) {
         size_t name_len = arg_end - (arg_start + NN_LENGTH);
         size_t copy_len = std::min(name_len, NICE_NAME_BYTES - 1);
         memcpy(mNiceName, arg_start + NN_LENGTH, copy_len);
@@ -196,21 +196,21 @@
         }
         continue;
       }
-      if (arg_end - arg_start == IW_LENGTH
-          && strncmp(arg_start, INVOKE_WITH, IW_LENGTH) == 0) {
+      if (static_cast<size_t>(arg_end - arg_start) == IW_LENGTH &&
+          strncmp(arg_start, INVOKE_WITH, IW_LENGTH) == 0) {
         // This also removes the need for invoke-with security checks here.
         return false;
       }
-      if (arg_end - arg_start == CZ_LENGTH
-          && strncmp(arg_start, CHILD_ZYGOTE, CZ_LENGTH) == 0) {
+      if (static_cast<size_t>(arg_end - arg_start) == CZ_LENGTH &&
+          strncmp(arg_start, CHILD_ZYGOTE, CZ_LENGTH) == 0) {
         return false;
       }
-      if (arg_end - arg_start >= CA_LENGTH
-          && strncmp(arg_start, CAPABILITIES, CA_LENGTH) == 0) {
+      if (static_cast<size_t>(arg_end - arg_start) >= CA_LENGTH &&
+          strncmp(arg_start, CAPABILITIES, CA_LENGTH) == 0) {
         return false;
       }
-      if (arg_end - arg_start >= SU_LENGTH
-          && strncmp(arg_start, SETUID, SU_LENGTH) == 0) {
+      if (static_cast<size_t>(arg_end - arg_start) >= SU_LENGTH &&
+          strncmp(arg_start, SETUID, SU_LENGTH) == 0) {
         int uid = digitsVal(arg_start + SU_LENGTH, arg_end);
         if (uid < minUid) {
           return false;
@@ -218,8 +218,8 @@
         saw_setuid = true;
         continue;
       }
-      if (arg_end - arg_start >= SG_LENGTH
-          && strncmp(arg_start, SETGID, SG_LENGTH) == 0) {
+      if (static_cast<size_t>(arg_end - arg_start) >= SG_LENGTH &&
+          strncmp(arg_start, SETGID, SG_LENGTH) == 0) {
         int gid = digitsVal(arg_start + SG_LENGTH, arg_end);
         if (gid == -1) {
           return false;
@@ -422,7 +422,7 @@
 
   bool first_time = true;
   do {
-    if (credentials.uid != expected_uid) {
+    if (credentials.uid != static_cast<uid_t>(expected_uid)) {
       return JNI_FALSE;
     }
     n_buffer->readAllLines(first_time ? fail_fn_1 : fail_fn_n);
diff --git a/media/jni/android_media_MediaMetricsJNI.cpp b/media/jni/android_media_MediaMetricsJNI.cpp
index 08a8d89..2769dbc 100644
--- a/media/jni/android_media_MediaMetricsJNI.cpp
+++ b/media/jni/android_media_MediaMetricsJNI.cpp
@@ -127,7 +127,7 @@
     if (item->getTimestamp() > 0) {
         bh.put(mediametrics::BUNDLE_TIMESTAMP, (int64_t)item->getTimestamp());
     }
-    if (item->getUid() != -1) {
+    if (static_cast<int32_t>(item->getUid()) != -1) {
         bh.put(mediametrics::BUNDLE_UID, (int32_t)item->getUid());
     }
     for (const auto &prop : *item) {