diff --git a/base/HidlSupport.cpp b/base/HidlSupport.cpp
index f97f216..af805b9 100644
--- a/base/HidlSupport.cpp
+++ b/base/HidlSupport.cpp
@@ -35,10 +35,8 @@
 }
 }  // namespace details
 
-hidl_handle::hidl_handle() {
-    memset(this, 0, sizeof(*this));
-    // mHandle = nullptr;
-    // mOwnsHandle = false;
+hidl_handle::hidl_handle() : mHandle(nullptr), mOwnsHandle(false) {
+    memset(mPad, 0, sizeof(mPad));
 }
 
 hidl_handle::~hidl_handle() {
@@ -138,11 +136,8 @@
 
 static const char *const kEmptyString = "";
 
-hidl_string::hidl_string() {
-    memset(this, 0, sizeof(*this));
-    // mSize is zero
-    // mOwnsBuffer is false
-    mBuffer = kEmptyString;
+hidl_string::hidl_string() : mBuffer(kEmptyString), mSize(0), mOwnsBuffer(false) {
+    memset(mPad, 0, sizeof(mPad));
 }
 
 hidl_string::~hidl_string() {
diff --git a/base/include/hidl/HidlSupport.h b/base/include/hidl/HidlSupport.h
index 89aa5a9..71448da 100644
--- a/base/include/hidl/HidlSupport.h
+++ b/base/include/hidl/HidlSupport.h
@@ -20,18 +20,24 @@
 #include <algorithm>
 #include <array>
 #include <iterator>
-#include <cutils/native_handle.h>
 #include <hidl/HidlInternal.h>
-#include <hidl/Status.h>
 #include <map>
 #include <sstream>
 #include <stddef.h>
 #include <tuple>
 #include <type_traits>
+#include <vector>
+
+// no requirements on types not used in scatter/gather
+// no requirements on other libraries
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wpadded"
+#include <cutils/native_handle.h>
+#include <hidl/Status.h>
 #include <utils/Errors.h>
 #include <utils/RefBase.h>
 #include <utils/StrongPointer.h>
-#include <vector>
+#pragma clang diagnostic pop
 
 namespace android {
 
@@ -123,8 +129,9 @@
 private:
     void freeHandle();
 
-    details::hidl_pointer<const native_handle_t> mHandle __attribute__ ((aligned(8)));
-    bool mOwnsHandle __attribute ((aligned(8)));
+    details::hidl_pointer<const native_handle_t> mHandle;
+    bool mOwnsHandle;
+    uint8_t mPad[7];
 };
 
 struct hidl_string {
@@ -174,6 +181,7 @@
     details::hidl_pointer<const char> mBuffer;
     uint32_t mSize;  // NOT including the terminating '\0'.
     bool mOwnsBuffer; // if true then mBuffer is a mutable char *
+    uint8_t mPad[3];
 
     // copy from data with size. Assume that my memory is freed
     // (through clear(), for example)
@@ -294,9 +302,9 @@
     static const size_t kOffsetOfName;
 
 private:
-    hidl_handle mHandle __attribute__ ((aligned(8)));
-    uint64_t mSize __attribute__ ((aligned(8)));
-    hidl_string mName __attribute__ ((aligned(8)));
+    hidl_handle mHandle;
+    uint64_t mSize;
+    hidl_string mName;
 };
 
 // HidlMemory is a wrapper class to support sp<> for hidl_memory. It also
@@ -328,15 +336,12 @@
 struct hidl_vec {
     using value_type = T;
 
-    hidl_vec() {
+    hidl_vec() : mBuffer(nullptr), mSize(0), mOwnsBuffer(true) {
         static_assert(hidl_vec<T>::kOffsetOfBuffer == 0, "wrong offset");
 
-        memset(this, 0, sizeof(*this));
-        // mSize is 0
-        // mBuffer is nullptr
+        // mOwnsBuffer true to match original implementation
 
-        // this is for consistency with the original implementation
-        mOwnsBuffer = true;
+        memset(mPad, 0, sizeof(mPad));
     }
 
     // Note, does not initialize primitive types.
@@ -581,6 +586,7 @@
     details::hidl_pointer<T> mBuffer;
     uint32_t mSize;
     bool mOwnsBuffer;
+    uint8_t mPad[3];
 
     // copy from an array-like object, assuming my resources are freed.
     template <typename Array>
diff --git a/test_main.cpp b/test_main.cpp
index 7b6781a..083cee4 100644
--- a/test_main.cpp
+++ b/test_main.cpp
@@ -16,11 +16,16 @@
 
 #define LOG_TAG "LibHidlTest"
 
+#pragma clang diagnostic push
+#pragma clang diagnostic fatal "-Wpadded"
+#include <hidl/HidlInternal.h>
+#include <hidl/HidlSupport.h>
+#pragma clang diagnostic pop
+
 #include <android-base/logging.h>
 #include <android/hidl/memory/1.0/IMemory.h>
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
-#include <hidl/HidlSupport.h>
 #include <hidl/ServiceManagement.h>
 #include <hidl/Status.h>
 #include <hidl/TaskRunner.h>
@@ -570,6 +575,51 @@
     EXPECT_TRUE(isLibraryOpen(kLib));
 }
 
+template <typename T, size_t start, size_t end>
+static void assertZeroInRange(const T* t) {
+    static_assert(start < sizeof(T));
+    static_assert(end <= sizeof(T));
+
+    const uint8_t* ptr = reinterpret_cast<const uint8_t*>(t);
+
+    for (size_t i = start; i < end; i++) {
+        EXPECT_EQ(0, ptr[i]);
+    }
+}
+
+template <typename T, size_t start, size_t end>
+static void uninitTest() {
+    uint8_t buf[sizeof(T)];
+    memset(buf, 0xFF, sizeof(T));
+
+    T* type = new (buf) T;
+    assertZeroInRange<T, start, end>(type);
+    type->~T();
+}
+
+TEST_F(LibHidlTest, HidlVecUninit) {
+    using ::android::hardware::hidl_vec;
+    struct SomeType {};
+    static_assert(sizeof(hidl_vec<SomeType>) == 16);
+
+    // padding after mOwnsBuffer
+    uninitTest<hidl_vec<SomeType>, 13, 16>();
+}
+TEST_F(LibHidlTest, HidlHandleUninit) {
+    using ::android::hardware::hidl_handle;
+    static_assert(sizeof(hidl_handle) == 16);
+
+    // padding after mOwnsHandle
+    uninitTest<hidl_handle, 9, 16>();
+}
+TEST_F(LibHidlTest, HidlStringUninit) {
+    using ::android::hardware::hidl_string;
+    static_assert(sizeof(hidl_string) == 16);
+
+    // padding after mOwnsBuffer
+    uninitTest<hidl_string, 13, 16>();
+}
+
 int main(int argc, char **argv) {
     ::testing::InitGoogleTest(&argc, argv);
     return RUN_ALL_TESTS();
diff --git a/transport/include/hidl/HidlBinderSupport.h b/transport/include/hidl/HidlBinderSupport.h
index 5dec5cd..05f7fab 100644
--- a/transport/include/hidl/HidlBinderSupport.h
+++ b/transport/include/hidl/HidlBinderSupport.h
@@ -204,10 +204,17 @@
     if (binderIface.get() == nullptr) {
         return nullptr;
     }
+
     if (binderIface->localBinder() == nullptr) {
         return new ProxyType(binderIface);
     }
+
+    // Ensure that IBinder is BnHwBase (not JHwBinder, for instance)
+    if (!binderIface->checkSubclass(IBase::descriptor)) {
+        return new ProxyType(binderIface);
+    }
     sp<IBase> base = static_cast<BnHwBase*>(binderIface.get())->getImpl();
+
     if (details::canCastInterface(base.get(), IType::descriptor)) {
         StubType* stub = static_cast<StubType*>(binderIface.get());
         return stub->getImpl();