Replace Q_ALIGNOF usage in qtbase with C++11 alignof keyword

The macro is not documented, so not part of the public Qt API. It is
made obsolete by the alignof keyword in C++11.

Remove the usage of the macro across qtbase, in particular the
workarounds for compilers that didn't support alignof, and that will
not be supported in Qt 6.

The macro definition is left in place, no need to break existing
code.

Task-number: QTBUG-76414
Change-Id: I1cfedcd4dd748128696cdfb546d97aae4f98c3da
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

src/corelib/global/qcompilerdetection.h

@@ -91,7 +91,6 @@
 #  define Q_OUTOFLINE_TEMPLATE inline
 #  define Q_COMPILER_MANGLES_RETURN_TYPE
 #  define Q_FUNC_INFO __FUNCSIG__
-#  define Q_ALIGNOF(type) __alignof(type)
 #  define Q_DECL_ALIGN(n) __declspec(align(n))
 #  define Q_ASSUME_IMPL(expr) __assume(expr)
 #  define Q_UNREACHABLE_IMPL() __assume(0)
@@ -222,7 +221,6 @@
 #  endif
 
 #  define Q_FUNC_INFO       __PRETTY_FUNCTION__
-#  define Q_ALIGNOF(type)   __alignof__(type)
 #  define Q_TYPEOF(expr)    __typeof__(expr)
 #  define Q_DECL_DEPRECATED __attribute__ ((__deprecated__))
 #  define Q_DECL_ALIGN(n)   __attribute__((__aligned__(n)))
@@ -272,7 +270,6 @@
 #  if __xlC__ < 0x400
 #    error "Compiler not supported"
 #  elif __xlC__ >= 0x0600
-#    define Q_ALIGNOF(type)     __alignof__(type)
 #    define Q_TYPEOF(expr)      __typeof__(expr)
 #    define Q_DECL_ALIGN(n)     __attribute__((__aligned__(n)))
 #    define Q_PACKED            __attribute__((__packed__))
@@ -352,7 +349,6 @@
 #    define Q_PACKED __attribute__ ((__packed__))
 #    define Q_FUNC_INFO       __PRETTY_FUNCTION__
 #    define Q_TYPEOF(expr)      __typeof__(expr)
-#    define Q_ALIGNOF(type)     __alignof__(type)
 #    define Q_UNREACHABLE_IMPL()
 #    if defined(__cplusplus)
 #      define Q_COMPILER_AUTO_TYPE
@@ -450,7 +446,6 @@
 #    define QT_NO_TEMPLATE_TEMPLATE_PARAMETERS
    /* see http://developers.sun.com/sunstudio/support/Ccompare.html */
 #    if __SUNPRO_CC >= 0x590
-#      define Q_ALIGNOF(type)   __alignof__(type)
 #      define Q_TYPEOF(expr)    __typeof__(expr)
 #      define Q_DECL_ALIGN(n)   __attribute__((__aligned__(n)))
 #    endif
@@ -1128,8 +1123,7 @@
 #endif
 #define Q_DECL_NOTHROW Q_DECL_NOEXCEPT
 
-#if defined(Q_COMPILER_ALIGNOF)
+#ifndef Q_ALIGNOF
-#  undef Q_ALIGNOF
 # define Q_ALIGNOF(x)  alignof(x)
 #endif
 

src/corelib/global/qglobal.h

@@ -499,53 +499,6 @@ Q_CORE_EXPORT Q_DECL_CONST_FUNCTION const char *qVersion(void) Q_DECL_NOEXCEPT;
 # define Q_DESTRUCTOR_FUNCTION(AFUNC) Q_DESTRUCTOR_FUNCTION0(AFUNC)
 #endif
 
-namespace QtPrivate {
-    template <class T>
-    struct AlignOfHelper
-    {
-        char c;
-        T type;
-
-        AlignOfHelper();
-        ~AlignOfHelper();
-    };
-
-    template <class T>
-    struct AlignOf_Default
-    {
-        enum { Value = sizeof(AlignOfHelper<T>) - sizeof(T) };
-    };
-
-    template <class T> struct AlignOf : AlignOf_Default<T> { };
-    template <class T> struct AlignOf<T &> : AlignOf<T> {};
-    template <class T> struct AlignOf<T &&> : AlignOf<T> {};
-    template <size_t N, class T> struct AlignOf<T[N]> : AlignOf<T> {};
-
-#if defined(Q_PROCESSOR_X86_32) && !defined(Q_OS_WIN)
-    template <class T> struct AlignOf_WorkaroundForI386Abi { enum { Value = sizeof(T) }; };
-
-    // x86 ABI weirdness
-    // Alignment of naked type is 8, but inside struct has alignment 4.
-    template <> struct AlignOf<double>  : AlignOf_WorkaroundForI386Abi<double> {};
-    template <> struct AlignOf<qint64>  : AlignOf_WorkaroundForI386Abi<qint64> {};
-    template <> struct AlignOf<quint64> : AlignOf_WorkaroundForI386Abi<quint64> {};
-#ifdef Q_CC_CLANG
-    // GCC and Clang seem to disagree wrt to alignment of arrays
-    template <size_t N> struct AlignOf<double[N]>   : AlignOf_Default<double> {};
-    template <size_t N> struct AlignOf<qint64[N]>   : AlignOf_Default<qint64> {};
-    template <size_t N> struct AlignOf<quint64[N]>  : AlignOf_Default<quint64> {};
-#endif
-#endif
-} // namespace QtPrivate
-
-#define QT_EMULATED_ALIGNOF(T) \
-    (size_t(QT_PREPEND_NAMESPACE(QtPrivate)::AlignOf<T>::Value))
-
-#ifndef Q_ALIGNOF
-#define Q_ALIGNOF(T) QT_EMULATED_ALIGNOF(T)
-#endif
-
-
 /*
   quintptr and qptrdiff is guaranteed to be the same size as a pointer, i.e.
 

src/corelib/global/qrandom.h

@@ -196,7 +196,7 @@ private:
         RandomEngine &engine() { return twister; }
         const RandomEngine &engine() const { return twister; }
 #else
-        std::aligned_storage<sizeof(RandomEngine), Q_ALIGNOF(RandomEngine)>::type buffer;
+        std::aligned_storage<sizeof(RandomEngine), alignof(RandomEngine)>::type buffer;
         RandomEngine &engine() { return reinterpret_cast<RandomEngine &>(buffer); }
         const RandomEngine &engine() const { return reinterpret_cast<const RandomEngine &>(buffer); }
 #endif

src/corelib/kernel/qmetaobjectbuilder.cpp

@@ -1103,7 +1103,7 @@ int QMetaStringTable::enter(const QByteArray &value)
 
 int QMetaStringTable::preferredAlignment()
 {
-    return Q_ALIGNOF(QByteArrayData);
+    return alignof(QByteArrayData);
 }
 
 // Returns the size (in bytes) required for serializing this string table.

src/corelib/kernel/qvariant.cpp

@@ -1470,7 +1470,7 @@ static void customConstruct(QVariant::Private *d, const void *copy)
     } else {
         // Private::Data contains long long, and long double is the biggest standard type.
         const size_t maxAlignment =
-            qMax(Q_ALIGNOF(QVariant::Private::Data), Q_ALIGNOF(long double));
+            qMax(alignof(QVariant::Private::Data), alignof(long double));
         const size_t s = sizeof(QVariant::PrivateShared);
         const size_t offset = s + ((s * maxAlignment - s) % maxAlignment);
         void *data = operator new(offset + size);

src/corelib/serialization/qcborvalue_p.h

@@ -147,8 +147,8 @@ public:
         qptrdiff offset = data.size();
 
         // align offset
-        offset += Q_ALIGNOF(QtCbor::ByteData) - 1;
+        offset += alignof(QtCbor::ByteData) - 1;
-        offset &= ~(Q_ALIGNOF(QtCbor::ByteData) - 1);
+        offset &= ~(alignof(QtCbor::ByteData) - 1);
 
         qptrdiff increment = qptrdiff(sizeof(QtCbor::ByteData)) + len;
 
@@ -170,7 +170,7 @@ public:
             return nullptr;
 
         size_t offset = size_t(e.value);
-        Q_ASSERT((offset % Q_ALIGNOF(QtCbor::ByteData)) == 0);
+        Q_ASSERT((offset % alignof(QtCbor::ByteData)) == 0);
         Q_ASSERT(offset + sizeof(QtCbor::ByteData) <= size_t(data.size()));
 
         auto b = reinterpret_cast<const QtCbor::ByteData *>(data.constData() + offset);

src/corelib/tools/qarraydata.cpp

@@ -193,7 +193,7 @@ QArrayData *QArrayData::allocate(size_t objectSize, size_t alignment,
         size_t capacity, AllocationOptions options) noexcept
 {
     // Alignment is a power of two
-    Q_ASSERT(alignment >= Q_ALIGNOF(QArrayData)
+    Q_ASSERT(alignment >= alignof(QArrayData)
             && !(alignment & (alignment - 1)));
 
     // Don't allocate empty headers
@@ -207,12 +207,12 @@ QArrayData *QArrayData::allocate(size_t objectSize, size_t alignment,
 
     size_t headerSize = sizeof(QArrayData);
 
-    // Allocate extra (alignment - Q_ALIGNOF(QArrayData)) padding bytes so we
+    // Allocate extra (alignment - alignof(QArrayData)) padding bytes so we
     // can properly align the data array. This assumes malloc is able to
     // provide appropriate alignment for the header -- as it should!
     // Padding is skipped when allocating a header for RawData.
     if (!(options & RawData))
-        headerSize += (alignment - Q_ALIGNOF(QArrayData));
+        headerSize += (alignment - alignof(QArrayData));
 
     if (headerSize > size_t(MaxAllocSize))
         return nullptr;
@@ -256,7 +256,7 @@ void QArrayData::deallocate(QArrayData *data, size_t objectSize,
         size_t alignment) noexcept
 {
     // Alignment is a power of two
-    Q_ASSERT(alignment >= Q_ALIGNOF(QArrayData)
+    Q_ASSERT(alignment >= alignof(QArrayData)
             && !(alignment & (alignment - 1)));
     Q_UNUSED(objectSize) Q_UNUSED(alignment)
 

src/corelib/tools/qarraydata.h

@@ -222,7 +222,7 @@ struct QTypedArrayData
     {
         Q_STATIC_ASSERT(sizeof(QTypedArrayData) == sizeof(QArrayData));
         return static_cast<QTypedArrayData *>(QArrayData::allocate(sizeof(T),
-                    Q_ALIGNOF(AlignmentDummy), capacity, options));
+                    alignof(AlignmentDummy), capacity, options));
     }
 
     static QTypedArrayData *reallocateUnaligned(QTypedArrayData *data, size_t capacity,
@@ -236,7 +236,7 @@ struct QTypedArrayData
     static void deallocate(QArrayData *data)
     {
         Q_STATIC_ASSERT(sizeof(QTypedArrayData) == sizeof(QArrayData));
-        QArrayData::deallocate(data, sizeof(T), Q_ALIGNOF(AlignmentDummy));
+        QArrayData::deallocate(data, sizeof(T), alignof(AlignmentDummy));
     }
 
     static QTypedArrayData *fromRawData(const T *data, size_t n,
@@ -295,7 +295,7 @@ struct QArrayDataPointerRef
 
 #define Q_STATIC_ARRAY_DATA_HEADER_INITIALIZER(type, size) \
     Q_STATIC_ARRAY_DATA_HEADER_INITIALIZER_WITH_OFFSET(size,\
-        ((sizeof(QArrayData) + (Q_ALIGNOF(type) - 1)) & ~(Q_ALIGNOF(type) - 1) )) \
+        ((sizeof(QArrayData) + (alignof(type) - 1)) & ~(alignof(type) - 1) )) \
     /**/
 
 ////////////////////////////////////////////////////////////////////////////////

src/corelib/tools/qcontiguouscache.h

@@ -166,7 +166,7 @@ private:
     }
     int alignOfTypedData() const
     {
-        return qMax<int>(sizeof(void*), Q_ALIGNOF(Data));
+        return qMax<int>(sizeof(void*), alignof(Data));
     }
 };
 

src/corelib/tools/qhash.h

@@ -235,7 +235,7 @@ class QHash
         return reinterpret_cast<Node *>(node);
     }
 
-    static inline int alignOfNode() { return qMax<int>(sizeof(void*), Q_ALIGNOF(Node)); }
+    static inline int alignOfNode() { return qMax<int>(sizeof(void*), alignof(Node)); }
 
 public:
     inline QHash() noexcept : d(const_cast<QHashData *>(&QHashData::shared_null)) { }

src/corelib/tools/qmap.h

@@ -219,7 +219,7 @@ struct QMapData : public QMapDataBase
 
     Node *createNode(const Key &k, const T &v, Node *parent = nullptr, bool left = false)
     {
-        Node *n = static_cast<Node *>(QMapDataBase::createNode(sizeof(Node), Q_ALIGNOF(Node),
+        Node *n = static_cast<Node *>(QMapDataBase::createNode(sizeof(Node), alignof(Node),
                                       parent, left));
         QT_TRY {
             new (&n->key) Key(k);
@@ -243,7 +243,7 @@ struct QMapData : public QMapDataBase
     void destroy() {
         if (root()) {
             root()->destroySubTree();
-            freeTree(header.left, Q_ALIGNOF(Node));
+            freeTree(header.left, alignof(Node));
         }
         freeData(this);
     }

src/gui/text/qfontengine_qpf2.cpp

@@ -168,7 +168,7 @@ const QFontEngineQPF2::Glyph *QFontEngineQPF2::findGlyph(glyph_t g) const
 
 bool QFontEngineQPF2::verifyHeader(const uchar *data, int size)
 {
-    VERIFY(quintptr(data) % Q_ALIGNOF(Header) == 0);
+    VERIFY(quintptr(data) % alignof(Header) == 0);
     VERIFY(size >= int(sizeof(Header)));
     const Header *header = reinterpret_cast<const Header *>(data);
     if (header->magic[0] != 'Q'

tests/auto/corelib/global/qglobal/tst_qglobal.cpp

@@ -49,7 +49,6 @@ private slots:
     void qConstructorFunction();
     void qCoreAppStartupFunction();
     void qCoreAppStartupFunctionRestart();
-    void qAlignOf();
     void integerForSize();
     void qprintable();
     void qprintable_data();
@@ -434,106 +433,6 @@ template <class T> struct AlignmentInStruct { T dummy; };
 typedef int (*fun) ();
 typedef int (Empty::*memFun) ();
 
-#define TEST_AlignOf(type, alignment)                                       \
-    do {                                                                    \
-        TEST_AlignOf_impl(type, alignment);                                 \
-                                                                            \
-        TEST_AlignOf_impl(type &, alignment);                               \
-        TEST_AlignOf_RValueRef(type &&, alignment);                         \
-                                                                            \
-        TEST_AlignOf_impl(type [5], alignment);                             \
-        TEST_AlignOf_impl(type (&) [5], alignment);                         \
-                                                                            \
-        TEST_AlignOf_impl(AlignmentInStruct<type>, alignment);              \
-                                                                            \
-        /* Some internal sanity validation, just for fun */                 \
-        TEST_AlignOf_impl(AlignmentInStruct<type [5]>, alignment);          \
-        TEST_AlignOf_impl(AlignmentInStruct<type &>, Q_ALIGNOF(void *));    \
-        TEST_AlignOf_impl(AlignmentInStruct<type (&) [5]>,                  \
-                Q_ALIGNOF(void *));                                         \
-        TEST_AlignOf_RValueRef(AlignmentInStruct<type &&>,                  \
-                Q_ALIGNOF(void *));                                         \
-    } while (false)                                                         \
-    /**/
-
-#define TEST_AlignOf_RValueRef(type, alignment) \
-        TEST_AlignOf_impl(type, alignment)
-
-#define TEST_AlignOf_impl(type, alignment) \
-    do { \
-        QCOMPARE(Q_ALIGNOF(type), size_t(alignment)); \
-        /* Compare to native operator for compilers that support it,
-           otherwise...  erm... check consistency! :-) */ \
-        QCOMPARE(alignof(type), Q_ALIGNOF(type)); \
-    } while (false)
-    /**/
-
-void tst_QGlobal::qAlignOf()
-{
-    // Built-in types, except 64-bit integers and double
-    TEST_AlignOf(char, 1);
-    TEST_AlignOf(signed char, 1);
-    TEST_AlignOf(unsigned char, 1);
-    TEST_AlignOf(qint8, 1);
-    TEST_AlignOf(quint8, 1);
-    TEST_AlignOf(qint16, 2);
-    TEST_AlignOf(quint16, 2);
-    TEST_AlignOf(qint32, 4);
-    TEST_AlignOf(quint32, 4);
-    TEST_AlignOf(void *, sizeof(void *));
-
-    // Depends on platform and compiler, disabling test for now
-    // TEST_AlignOf(long double, 16);
-
-    // Empty struct
-    TEST_AlignOf(Empty, 1);
-
-    // Function pointers
-    TEST_AlignOf(fun, Q_ALIGNOF(void *));
-    TEST_AlignOf(memFun, Q_ALIGNOF(void *));
-
-
-    // 64-bit integers and double
-    TEST_AlignOf_impl(qint64, 8);
-    TEST_AlignOf_impl(quint64, 8);
-    TEST_AlignOf_impl(double, 8);
-
-    TEST_AlignOf_impl(qint64 &, 8);
-    TEST_AlignOf_impl(quint64 &, 8);
-    TEST_AlignOf_impl(double &, 8);
-
-    TEST_AlignOf_RValueRef(qint64 &&, 8);
-    TEST_AlignOf_RValueRef(quint64 &&, 8);
-    TEST_AlignOf_RValueRef(double &&, 8);
-
-    // 32-bit x86 ABI idiosyncrasies
-#if defined(Q_PROCESSOR_X86_32) && !defined(Q_OS_WIN)
-    TEST_AlignOf_impl(AlignmentInStruct<qint64>, 4);
-#else
-    TEST_AlignOf_impl(AlignmentInStruct<qint64>, 8);
-#endif
-
-    TEST_AlignOf_impl(AlignmentInStruct<quint64>, Q_ALIGNOF(AlignmentInStruct<qint64>));
-    TEST_AlignOf_impl(AlignmentInStruct<double>, Q_ALIGNOF(AlignmentInStruct<qint64>));
-
-    // 32-bit x86 ABI, Clang disagrees with gcc
-#if !defined(Q_PROCESSOR_X86_32) || !defined(Q_CC_CLANG) || defined(Q_OS_ANDROID)
-    TEST_AlignOf_impl(qint64 [5],       Q_ALIGNOF(qint64));
-#else
-    TEST_AlignOf_impl(qint64 [5],       Q_ALIGNOF(AlignmentInStruct<qint64>));
-#endif
-
-    TEST_AlignOf_impl(qint64 (&) [5],   Q_ALIGNOF(qint64 [5]));
-    TEST_AlignOf_impl(quint64 [5],      Q_ALIGNOF(quint64 [5]));
-    TEST_AlignOf_impl(quint64 (&) [5],  Q_ALIGNOF(quint64 [5]));
-    TEST_AlignOf_impl(double [5],       Q_ALIGNOF(double [5]));
-    TEST_AlignOf_impl(double (&) [5],   Q_ALIGNOF(double [5]));
-}
-
-#undef TEST_AlignOf
-#undef TEST_AlignOf_RValueRef
-#undef TEST_AlignOf_impl
-
 void tst_QGlobal::integerForSize()
 {
     // compile-only test:

tests/auto/corelib/kernel/qmetatype/tst_qmetatype.cpp

@@ -1024,9 +1024,9 @@ static void testConstructHelper()
     typedef typename MetaEnumToType<ID>::Type Type;
     QMetaType info(ID);
     int size = info.sizeOf();
-    void *storage1 = qMallocAligned(size, Q_ALIGNOF(Type));
+    void *storage1 = qMallocAligned(size, alignof(Type));
     void *actual1 = QMetaType::construct(ID, storage1, /*copy=*/0);
-    void *storage2 = qMallocAligned(size, Q_ALIGNOF(Type));
+    void *storage2 = qMallocAligned(size, alignof(Type));
     void *actual2 = info.construct(storage2, /*copy=*/0);
     QCOMPARE(actual1, storage1);
     QCOMPARE(actual2, storage2);
@@ -1178,9 +1178,9 @@ static void testConstructCopyHelper()
     QMetaType info(ID);
     int size = QMetaType::sizeOf(ID);
     QCOMPARE(info.sizeOf(), size);
-    void *storage1 = qMallocAligned(size, Q_ALIGNOF(Type));
+    void *storage1 = qMallocAligned(size, alignof(Type));
     void *actual1 = QMetaType::construct(ID, storage1, expected);
-    void *storage2 = qMallocAligned(size, Q_ALIGNOF(Type));
+    void *storage2 = qMallocAligned(size, alignof(Type));
     void *actual2 = info.construct(storage2, expected);
     QCOMPARE(actual1, storage1);
     QCOMPARE(actual2, storage2);

tests/auto/corelib/thread/qatomicint/tst_qatomicint.cpp

@@ -237,28 +237,23 @@ template <typename T> struct TypeInStruct { T type; };
 
 void tst_QAtomicInt::alignment()
 {
-#ifdef Q_ALIGNOF
+    Q_STATIC_ASSERT(alignof(QBasicAtomicInt) == alignof(TypeInStruct<int>));
-    // this will cause a build error if the alignment isn't the same
+    Q_STATIC_ASSERT(alignof(QBasicAtomicInt) == alignof(TypeInStruct<int>));
-    char dummy1[Q_ALIGNOF(QBasicAtomicInt) == Q_ALIGNOF(TypeInStruct<int>) ? 1 : -1];
-    char dummy2[Q_ALIGNOF(QAtomicInt) == Q_ALIGNOF(TypeInStruct<int>) ? 1 : -1];
-    (void)dummy1; (void)dummy2;
 
 #ifdef Q_ATOMIC_INT32_IS_SUPPORTED
-    QCOMPARE(Q_ALIGNOF(QBasicAtomicInteger<int>), Q_ALIGNOF(TypeInStruct<int>));
+    QCOMPARE(alignof(QBasicAtomicInteger<int>), alignof(TypeInStruct<int>));
 #endif
 
 #ifdef Q_ATOMIC_INT16_IS_SUPPORTED
-    QCOMPARE(Q_ALIGNOF(QBasicAtomicInteger<short>), Q_ALIGNOF(TypeInStruct<short>));
+    QCOMPARE(alignof(QBasicAtomicInteger<short>), alignof(TypeInStruct<short>));
 #endif
 
 #ifdef Q_ATOMIC_INT8_IS_SUPPORTED
-    QCOMPARE(Q_ALIGNOF(QBasicAtomicInteger<char>), Q_ALIGNOF(TypeInStruct<char>));
+    QCOMPARE(alignof(QBasicAtomicInteger<char>), alignof(TypeInStruct<char>));
 #endif
 
 #ifdef Q_ATOMIC_INT64_IS_SUPPORTED
-    QCOMPARE(Q_ALIGNOF(QBasicAtomicInteger<qlonglong>), Q_ALIGNOF(TypeInStruct<qlonglong>));
+    QCOMPARE(alignof(QBasicAtomicInteger<qlonglong>), alignof(TypeInStruct<qlonglong>));
-#endif
-
 #endif
 }
 

tests/auto/corelib/thread/qatomicpointer/tst_qatomicpointer.cpp

@@ -108,11 +108,7 @@ void tst_QAtomicPointer::warningFree()
 
 void tst_QAtomicPointer::alignment()
 {
-#ifdef Q_ALIGNOF
+    Q_STATIC_ASSERT(alignof(QBasicAtomicPointer<void>) == alignof(void*));
-    // this will cause a build error if the alignment isn't the same
-    char dummy[Q_ALIGNOF(QBasicAtomicPointer<void>) == Q_ALIGNOF(void*) ? 1 : -1];
-    (void)dummy;
-#endif
 }
 
 void tst_QAtomicPointer::constructor()

tests/auto/corelib/tools/collections/tst_collections.cpp

@@ -3214,7 +3214,7 @@ void tst_Collections::forwardDeclared()
     { typedef QSet<T1> C; C *x = 0; /* C::iterator i; */ C::const_iterator j; Q_UNUSED(x) }
 }
 
-#if defined(Q_ALIGNOF) && defined(Q_DECL_ALIGN)
+#if defined(Q_DECL_ALIGN)
 
 class Q_DECL_ALIGN(4) Aligned4
 {
@@ -3228,7 +3228,7 @@ public:
     inline bool operator<(const Aligned4 &other) const { return i < other.i; }
     friend inline int qHash(const Aligned4 &a) { return qHash(a.i); }
 };
-Q_STATIC_ASSERT(Q_ALIGNOF(Aligned4) % 4 == 0);
+Q_STATIC_ASSERT(alignof(Aligned4) % 4 == 0);
 
 #if defined(Q_PROCESSOR_ARM)
 #  if defined(Q_COMPILER_ALIGNAS) && defined(__BIGGEST_ALIGNMENT__)
@@ -3254,7 +3254,7 @@ public:
     inline bool operator<(const AlignedBiggest &other) const { return i < other.i; }
     friend inline int qHash(const AlignedBiggest &a) { return qHash(a.i); }
 };
-Q_STATIC_ASSERT(Q_ALIGNOF(AlignedBiggest) % BIGGEST_ALIGNMENT_TO_TEST == 0);
+Q_STATIC_ASSERT(alignof(AlignedBiggest) % BIGGEST_ALIGNMENT_TO_TEST == 0);
 
 template<typename C>
 void testVectorAlignment()

tests/auto/corelib/tools/qarraydata/tst_qarraydata.cpp

@@ -160,7 +160,7 @@ void tst_QArrayData::referenceCounting()
 void tst_QArrayData::sharedNullEmpty()
 {
     QArrayData *null = const_cast<QArrayData *>(QArrayData::shared_null);
-    QArrayData *empty = QArrayData::allocate(1, Q_ALIGNOF(QArrayData), 0);
+    QArrayData *empty = QArrayData::allocate(1, alignof(QArrayData), 0);
 
     QVERIFY(null->ref.isStatic());
     QVERIFY(null->ref.isShared());
@@ -657,16 +657,16 @@ void tst_QArrayData::allocate_data()
         size_t objectSize;
         size_t alignment;
     } types[] = {
-        { "char", sizeof(char), Q_ALIGNOF(char) },
+        { "char", sizeof(char), alignof(char) },
-        { "short", sizeof(short), Q_ALIGNOF(short) },
+        { "short", sizeof(short), alignof(short) },
-        { "void *", sizeof(void *), Q_ALIGNOF(void *) }
+        { "void *", sizeof(void *), alignof(void *) }
     };
 
-    QArrayData *shared_empty = QArrayData::allocate(0, Q_ALIGNOF(QArrayData), 0);
+    QArrayData *shared_empty = QArrayData::allocate(0, alignof(QArrayData), 0);
     QVERIFY(shared_empty);
 
 #if !defined(QT_NO_UNSHARABLE_CONTAINERS)
-    QArrayData *unsharable_empty = QArrayData::allocate(0, Q_ALIGNOF(QArrayData), 0, QArrayData::Unsharable);
+    QArrayData *unsharable_empty = QArrayData::allocate(0, alignof(QArrayData), 0, QArrayData::Unsharable);
     QVERIFY(unsharable_empty);
 #endif
 
@@ -709,7 +709,7 @@ void tst_QArrayData::allocate()
 
     // Minimum alignment that can be requested is that of QArrayData.
     // Typically, this alignment is sizeof(void *) and ensured by malloc.
-    size_t minAlignment = qMax(alignment, Q_ALIGNOF(QArrayData));
+    size_t minAlignment = qMax(alignment, alignof(QArrayData));
 
     // Shared Empty
     QCOMPARE(QArrayData::allocate(objectSize, minAlignment, 0,
@@ -749,11 +749,11 @@ void tst_QArrayData::reallocate()
 
     // Maximum alignment that can be requested is that of QArrayData,
     // otherwise, we can't use reallocate().
-    Q_ASSERT(alignment <= Q_ALIGNOF(QArrayData));
+    Q_ASSERT(alignment <= alignof(QArrayData));
 
     // Minimum alignment that can be requested is that of QArrayData.
     // Typically, this alignment is sizeof(void *) and ensured by malloc.
-    size_t minAlignment = qMax(alignment, Q_ALIGNOF(QArrayData));
+    size_t minAlignment = qMax(alignment, alignof(QArrayData));
 
     int capacity = 10;
     Deallocator keeper(objectSize, minAlignment);
@@ -808,7 +808,7 @@ void tst_QArrayData::alignment()
 
     // Minimum alignment that can be requested is that of QArrayData.
     // Typically, this alignment is sizeof(void *) and ensured by malloc.
-    size_t minAlignment = qMax(alignment, Q_ALIGNOF(QArrayData));
+    size_t minAlignment = qMax(alignment, alignof(QArrayData));
 
     Deallocator keeper(sizeof(Unaligned), minAlignment);
     keeper.headers.reserve(100);
@@ -826,7 +826,7 @@ void tst_QArrayData::alignment()
         // allocated together
         QVERIFY(data->offset >= qptrdiff(sizeof(QArrayData)));
         QVERIFY(data->offset <= qptrdiff(sizeof(QArrayData)
-                    + minAlignment - Q_ALIGNOF(QArrayData)));
+                    + minAlignment - alignof(QArrayData)));
 
         // Data is aligned
         QCOMPARE(quintptr(quintptr(data->data()) % alignment), quintptr(0u));
@@ -886,7 +886,7 @@ void tst_QArrayData::typedData()
 
     {
         Deallocator keeper(sizeof(char),
-                Q_ALIGNOF(QTypedArrayData<char>::AlignmentDummy));
+                alignof(QTypedArrayData<char>::AlignmentDummy));
         QArrayData *array = QTypedArrayData<char>::allocate(10);
         keeper.headers.append(array);
 
@@ -906,7 +906,7 @@ void tst_QArrayData::typedData()
 
     {
         Deallocator keeper(sizeof(short),
-                Q_ALIGNOF(QTypedArrayData<short>::AlignmentDummy));
+                alignof(QTypedArrayData<short>::AlignmentDummy));
         QArrayData *array = QTypedArrayData<short>::allocate(10);
         keeper.headers.append(array);
 
@@ -926,7 +926,7 @@ void tst_QArrayData::typedData()
 
     {
         Deallocator keeper(sizeof(double),
-                Q_ALIGNOF(QTypedArrayData<double>::AlignmentDummy));
+                alignof(QTypedArrayData<double>::AlignmentDummy));
         QArrayData *array = QTypedArrayData<double>::allocate(10);
         keeper.headers.append(array);
 

tests/auto/gui/kernel/qguimetatype/tst_qguimetatype.cpp

@@ -316,30 +316,10 @@ void tst_QGuiMetaType::sizeOf()
     QCOMPARE(QMetaType::sizeOf(type), size);
 }
 
-#ifndef Q_ALIGNOF
-template<uint N>
-struct RoundToNextHighestPowerOfTwo
-{
-private:
-    enum { V1 = N-1 };
-    enum { V2 = V1 | (V1 >> 1) };
-    enum { V3 = V2 | (V2 >> 2) };
-    enum { V4 = V3 | (V3 >> 4) };
-    enum { V5 = V4 | (V4 >> 8) };
-    enum { V6 = V5 | (V5 >> 16) };
-public:
-    enum { Value = V6 + 1 };
-};
-#endif
-
 template<class T>
 struct TypeAlignment
 {
-#ifdef Q_ALIGNOF
+    enum { Value = alignof(T) };
-    enum { Value = Q_ALIGNOF(T) };
-#else
-    enum { Value = RoundToNextHighestPowerOfTwo<sizeof(T)>::Value };
-#endif
 };
 
 void tst_QGuiMetaType::flags_data()

tests/auto/other/compiler/tst_compiler.cpp

@@ -634,7 +634,7 @@ void tst_Compiler::cxx11_alignas()
     struct S {
         alignas(double) char c;
     };
-    QCOMPARE(Q_ALIGNOF(S), Q_ALIGNOF(double));
+    QCOMPARE(alignof(S), alignof(double));
 #endif
 }
 
@@ -1396,7 +1396,7 @@ void tst_Compiler::cxx11_unrestricted_unions()
         ~U() {}
     };
     U u;
-    std::aligned_storage<sizeof(QString), Q_ALIGNOF(QString)> as;
+    std::aligned_storage<sizeof(QString), alignof(QString)> as;
     Q_UNUSED(u);
     Q_UNUSED(as);
 

tests/benchmarks/corelib/tools/qvector/qrawvector.h

@@ -280,11 +280,7 @@ private:
     }
     static Q_DECL_CONSTEXPR int alignOfTypedData()
     {
-#ifdef Q_ALIGNOF
+        return alignof(AlignmentDummy);
-        return Q_ALIGNOF(AlignmentDummy);
-#else
-        return sizeof(void *);
-#endif
     }
 
 public: