diff --git a/include/gui/BufferItem.h b/include/gui/BufferItem.h
index 3ab63d0..5232d0f 100644
--- a/include/gui/BufferItem.h
+++ b/include/gui/BufferItem.h
@@ -74,13 +74,7 @@
     // to set by queueBuffer each time this slot is queued. This value
     // is guaranteed to be monotonically increasing for each newly
     // acquired buffer.
-    union {
-        int64_t mTimestamp;
-        struct {
-            uint32_t mTimestampLo;
-            uint32_t mTimestampHi;
-        };
-    };
+    int64_t mTimestamp;
 
     // mIsAutoTimestamp indicates whether mTimestamp was generated
     // automatically when the buffer was queued.
@@ -92,13 +86,7 @@
     android_dataspace mDataSpace;
 
     // mFrameNumber is the number of the queued frame for this slot.
-    union {
-        uint64_t mFrameNumber;
-        struct {
-            uint32_t mFrameNumberLo;
-            uint32_t mFrameNumberHi;
-        };
-    };
+    uint64_t mFrameNumber;
 
     // mSlot is the slot index of this buffer (default INVALID_BUFFER_SLOT).
     int mSlot;
diff --git a/libs/gui/Android.mk b/libs/gui/Android.mk
index 799b2b5..b497cb1 100644
--- a/libs/gui/Android.mk
+++ b/libs/gui/Android.mk
@@ -36,6 +36,9 @@
 # Don't warn about struct padding
 LOCAL_CPPFLAGS += -Wno-padded
 
+# android/sensors.h uses nested anonymous unions and anonymous structs
+LOCAL_CPPFLAGS += -Wno-nested-anon-types -Wno-gnu-anonymous-struct
+
 LOCAL_CPPFLAGS += -DDEBUG_ONLY_CODE=$(if $(filter userdebug eng,$(TARGET_BUILD_VARIANT)),1,0)
 
 LOCAL_SRC_FILES := \
diff --git a/libs/gui/BufferItem.cpp b/libs/gui/BufferItem.cpp
index 5e3924a..1357a4a 100644
--- a/libs/gui/BufferItem.cpp
+++ b/libs/gui/BufferItem.cpp
@@ -23,6 +23,21 @@
 
 namespace android {
 
+template<typename T>
+static inline constexpr uint32_t low32(const T n) {
+    return static_cast<uint32_t>(static_cast<uint64_t>(n));
+}
+
+template<typename T>
+static inline constexpr uint32_t high32(const T n) {
+    return static_cast<uint32_t>(static_cast<uint64_t>(n)>>32);
+}
+
+template<typename T>
+static inline constexpr T to64(const uint32_t lo, const uint32_t hi) {
+    return static_cast<T>(static_cast<uint64_t>(hi)<<32 | lo);
+}
+
 BufferItem::BufferItem() :
     mGraphicBuffer(NULL),
     mFence(NULL),
@@ -56,12 +71,12 @@
     addAligned(size, mCrop);
     addAligned(size, mTransform);
     addAligned(size, mScalingMode);
-    addAligned(size, mTimestampLo);
-    addAligned(size, mTimestampHi);
+    addAligned(size, low32(mTimestamp));
+    addAligned(size, high32(mTimestamp));
     addAligned(size, mIsAutoTimestamp);
     addAligned(size, mDataSpace);
-    addAligned(size, mFrameNumberLo);
-    addAligned(size, mFrameNumberHi);
+    addAligned(size, low32(mFrameNumber));
+    addAligned(size, high32(mFrameNumber));
     addAligned(size, mSlot);
     addAligned(size, mIsDroppable);
     addAligned(size, mAcquireCalled);
@@ -141,12 +156,12 @@
     writeAligned(buffer, size, mCrop);
     writeAligned(buffer, size, mTransform);
     writeAligned(buffer, size, mScalingMode);
-    writeAligned(buffer, size, mTimestampLo);
-    writeAligned(buffer, size, mTimestampHi);
+    writeAligned(buffer, size, low32(mTimestamp));
+    writeAligned(buffer, size, high32(mTimestamp));
     writeAligned(buffer, size, mIsAutoTimestamp);
     writeAligned(buffer, size, mDataSpace);
-    writeAligned(buffer, size, mFrameNumberLo);
-    writeAligned(buffer, size, mFrameNumberHi);
+    writeAligned(buffer, size, low32(mFrameNumber));
+    writeAligned(buffer, size, high32(mFrameNumber));
     writeAligned(buffer, size, mSlot);
     writeAligned(buffer, size, mIsDroppable);
     writeAligned(buffer, size, mAcquireCalled);
@@ -194,15 +209,20 @@
         return NO_MEMORY;
     }
 
+    uint32_t timestampLo = 0, timestampHi = 0;
+    uint32_t frameNumberLo = 0, frameNumberHi = 0;
+
     readAligned(buffer, size, mCrop);
     readAligned(buffer, size, mTransform);
     readAligned(buffer, size, mScalingMode);
-    readAligned(buffer, size, mTimestampLo);
-    readAligned(buffer, size, mTimestampHi);
+    readAligned(buffer, size, timestampLo);
+    readAligned(buffer, size, timestampHi);
+    mTimestamp = to64<int64_t>(timestampLo, timestampHi);
     readAligned(buffer, size, mIsAutoTimestamp);
     readAligned(buffer, size, mDataSpace);
-    readAligned(buffer, size, mFrameNumberLo);
-    readAligned(buffer, size, mFrameNumberHi);
+    readAligned(buffer, size, frameNumberLo);
+    readAligned(buffer, size, frameNumberHi);
+    mFrameNumber = to64<uint64_t>(frameNumberLo, frameNumberHi);
     readAligned(buffer, size, mSlot);
     readAligned(buffer, size, mIsDroppable);
     readAligned(buffer, size, mAcquireCalled);