Merge branch '4.7' of scm.dev.nokia.troll.no:qt/oslo-staging-2 into 4.7-integration

* '4.7' of scm.dev.nokia.troll.no:qt/oslo-staging-2: (24 commits)
  Add text decoration support to QStaticText
  Fix QString::arg: When specifying %L1, the group separator would be added even if the local specify QLocale::OmitGroupSeparator
  QtDeclarative: get rid of warnings in public header
  doc: Clarify documentation of QStaticText
  Fix scrollbar randomly popping up in QPlainTextEdit
  Remove the definition of QT_HAVE_NEON from qt.prf
  Use the fast Neon conversion for converting colors of jpeg images.
  Do the conversion from RGB888 to RGB32 using Neon
  Move the build of Neon file from painting.pri to gui.pro
  QSharedPointer documentation: specify that it is not safe to operate on the same object in different threads
  compilation with QT_NO_DEPRECATED
  Test we do not have compiler warnings in our headers with more options
  QStyleSheet documentation: QMenu's tear-off is styled with ::tearoff
  Doc: Fixed qdoc warnings.
  Fix QTextEngine overflow caused by extremely long text
  Replace the SSE prologues by a macro
  QDom: Do not crash on "<a:>text</a:>"
  Doc: Fixed typo.
  Doc: Fixed QML documentation errors.
  Doc: Merged in some of Thomas Zander's suggestions.
  ...

18 files changed, 417 insertions, 95 deletions

diff --git a/src/gui/graphicsview/qgraphicsitem.cpp b/src/gui/graphicsview/qgraphicsitem.cpp
index e1e27d2..0b3b164 100644
--- a/src/gui/graphicsview/qgraphicsitem.cpp
+++ b/src/gui/graphicsview/qgraphicsitem.cpp
@@ -7985,6 +7985,24 @@ void QGraphicsItemPrivate::resetHeight()
 */
 
 /*!
+    \property QGraphicsObject::children
+    \since 4.7
+    \internal
+*/
+
+/*!
+    \property QGraphicsObject::width
+    \since 4.7
+    \internal
+*/
+
+/*!
+    \property QGraphicsObject::height
+    \since 4.7
+    \internal
+*/
+
+/*!
     \class QAbstractGraphicsShapeItem
     \brief The QAbstractGraphicsShapeItem class provides a common base for
     all path items.
diff --git a/src/gui/graphicsview/qgraphicstransform.cpp b/src/gui/graphicsview/qgraphicstransform.cpp
index 7b69317..bd3f2ef 100644
--- a/src/gui/graphicsview/qgraphicstransform.cpp
+++ b/src/gui/graphicsview/qgraphicstransform.cpp
@@ -583,6 +583,27 @@ void QGraphicsRotation::applyTo(QMatrix4x4 *matrix) const
     \sa QGraphicsRotation::axis
 */
 
+/*!
+    \fn QGraphicsScale::xScaleChanged()
+    \since 4.7
+
+    This signal is emitted whenever the \l xScale property changes.
+*/
+
+/*!
+    \fn QGraphicsScale::yScaleChanged()
+    \since 4.7
+
+    This signal is emitted whenever the \l yScale property changes.
+*/
+
+/*!
+    \fn QGraphicsScale::zScaleChanged()
+    \since 4.7
+
+    This signal is emitted whenever the \l zScale property changes.
+*/
+
 #include "moc_qgraphicstransform.cpp"
 
 QT_END_NAMESPACE
diff --git a/src/gui/gui.pro b/src/gui/gui.pro
index 28440cc..3943e26 100644
--- a/src/gui/gui.pro
+++ b/src/gui/gui.pro
@@ -77,6 +77,25 @@ symbian {
     DEPLOYMENT = partial_upgrade $$DEPLOYMENT
 }
 
+neon:*-g++* {
+    DEFINES += QT_HAVE_NEON
+    QMAKE_CXXFLAGS *= -mfpu=neon
+    HEADERS += $$NEON_HEADERS
+    SOURCES += $$NEON_SOURCES
+
+    DRAWHELPER_NEON_ASM_FILES = $$NEON_ASM
+
+    neon_compiler.commands = $$QMAKE_CXX -c
+    neon_compiler.commands += $(CXXFLAGS) $(INCPATH) ${QMAKE_FILE_IN} -o ${QMAKE_FILE_OUT}
+    neon_compiler.dependency_type = TYPE_C
+    neon_compiler.output = ${QMAKE_VAR_OBJECTS_DIR}${QMAKE_FILE_BASE}$${first(QMAKE_EXT_OBJ)}
+    neon_compiler.input = DRAWHELPER_NEON_ASM_FILES
+    neon_compiler.variable_out = OBJECTS
+    neon_compiler.name = compiling[neon] ${QMAKE_FILE_IN}
+    silent:neon_compiler.commands = @echo compiling[neon] ${QMAKE_FILE_IN} && $$neon_compiler.commands
+    QMAKE_EXTRA_COMPILERS += neon_compiler
+}
+
 contains(QMAKE_MAC_XARCH, no) {
     DEFINES += QT_NO_MAC_XARCH
 } else {
diff --git a/src/gui/image/image.pri b/src/gui/image/image.pri
index b20a04f..f89706c 100644
--- a/src/gui/image/image.pri
+++ b/src/gui/image/image.pri
@@ -94,5 +94,6 @@ contains(QT_CONFIG, tiff):include($$PWD/qtiffhandler.pri)
 contains(QT_CONFIG, gif):include($$PWD/qgifhandler.pri)
 
 # SIMD
+NEON_SOURCES += image/qimage_neon.cpp
 SSE2_SOURCES += image/qimage_sse2.cpp
 SSSE3_SOURCES += image/qimage_ssse3.cpp
diff --git a/src/gui/image/qimage.cpp b/src/gui/image/qimage.cpp
index cb834c0..ac148ee 100644
--- a/src/gui/image/qimage.cpp
+++ b/src/gui/image/qimage.cpp
@@ -3769,6 +3769,14 @@ void qInitImageConversions()
         converter_map[QImage::Format_RGB888][QImage::Format_ARGB32_Premultiplied] = convert_RGB888_to_RGB32_ssse3;
     }
 #endif
+#ifdef QT_HAVE_NEON
+    if (features & NEON) {
+        extern void convert_RGB888_to_RGB32_neon(QImageData *dest, const QImageData *src, Qt::ImageConversionFlags);
+        converter_map[QImage::Format_RGB888][QImage::Format_RGB32] = convert_RGB888_to_RGB32_neon;
+        converter_map[QImage::Format_RGB888][QImage::Format_ARGB32] = convert_RGB888_to_RGB32_neon;
+        converter_map[QImage::Format_RGB888][QImage::Format_ARGB32_Premultiplied] = convert_RGB888_to_RGB32_neon;
+    }
+#endif
 }
 
 /*!
diff --git a/src/gui/image/qimage_neon.cpp b/src/gui/image/qimage_neon.cpp
new file mode 100644
index 0000000..15bf472
--- /dev/null
+++ b/src/gui/image/qimage_neon.cpp
@@ -0,0 +1,114 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <qimage.h>
+#include <private/qimage_p.h>
+#include <private/qsimd_p.h>
+
+#ifdef QT_HAVE_NEON
+
+QT_BEGIN_NAMESPACE
+
+Q_GUI_EXPORT void QT_FASTCALL qt_convert_rgb888_to_rgb32_neon(quint32 *dst, const uchar *src, int len)
+{
+    if (!len)
+        return;
+
+    const quint32 *const end = dst + len;
+
+    // align dst on 64 bits
+    const int offsetToAlignOn8Bytes = (reinterpret_cast<quintptr>(dst) >> 2) & 0x1;
+    for (int i = 0; i < offsetToAlignOn8Bytes; ++i) {
+        *dst++ = qRgb(src[0], src[1], src[2]);
+        src += 3;
+    }
+
+    if ((len - offsetToAlignOn8Bytes) >= 8) {
+        const quint32 *const simdEnd = end - 7;
+        register uint8x8_t fullVector asm ("d3") = vdup_n_u8(0xff);
+        do {
+#if Q_BYTE_ORDER == Q_BIG_ENDIAN
+            asm volatile (
+                "vld3.8     { d4, d5, d6 }, [%[SRC]] !\n\t"
+                "vst4.8     { d3, d4, d5, d6 }, [%[DST],:64] !\n\t"
+                : [DST]"+r" (dst), [SRC]"+r" (src)
+                : "w"(fullVector)
+                : "memory", "d4", "d5", "d6"
+            );
+#else
+            asm volatile (
+                "vld3.8     { d0, d1, d2 }, [%[SRC]] !\n\t"
+                "vswp d0, d2\n\t"
+                "vst4.8     { d0, d1, d2, d3 }, [%[DST],:64] !\n\t"
+                : [DST]"+r" (dst), [SRC]"+r" (src)
+                : "w"(fullVector)
+                : "memory", "d0", "d1", "d2"
+            );
+#endif
+        } while (dst < simdEnd);
+    }
+
+    while (dst != end) {
+        *dst++ = qRgb(src[0], src[1], src[2]);
+        src += 3;
+    }
+}
+
+void convert_RGB888_to_RGB32_neon(QImageData *dest, const QImageData *src, Qt::ImageConversionFlags)
+{
+    Q_ASSERT(src->format == QImage::Format_RGB888);
+    Q_ASSERT(dest->format == QImage::Format_RGB32 || dest->format == QImage::Format_ARGB32 || dest->format == QImage::Format_ARGB32_Premultiplied);
+    Q_ASSERT(src->width == dest->width);
+    Q_ASSERT(src->height == dest->height);
+
+    const uchar *src_data = (uchar *) src->data;
+    quint32 *dest_data = (quint32 *) dest->data;
+
+    for (int i = 0; i < src->height; ++i) {
+        qt_convert_rgb888_to_rgb32_neon(dest_data, src_data, src->width);
+        src_data += src->bytes_per_line;
+        dest_data = (quint32 *)((uchar*)dest_data + dest->bytes_per_line);
+    }
+}
+
+QT_END_NAMESPACE
+
+#endif // QT_HAVE_NEON
diff --git a/src/gui/image/qjpeghandler.cpp b/src/gui/image/qjpeghandler.cpp
index d358a5e..eda5efb 100644
--- a/src/gui/image/qjpeghandler.cpp
+++ b/src/gui/image/qjpeghandler.cpp
@@ -803,9 +803,16 @@ bool QJpegHandlerPrivate::read(QImage *image)
 QJpegHandler::QJpegHandler()
     : d(new QJpegHandlerPrivate(this))
 {
-#if defined(QT_HAVE_SSSE3)
     const uint features = qDetectCPUFeatures();
-
+    Q_UNUSED(features);
+#if defined(QT_HAVE_NEON)
+    // from qimage_neon.cpp
+    Q_GUI_EXPORT void QT_FASTCALL qt_convert_rgb888_to_rgb32_neon(quint32 *dst, const uchar *src, int len);
+
+    if (features & NEON)
+        rgb888ToRgb32ConverterPtr = qt_convert_rgb888_to_rgb32_neon;
+#endif // QT_HAVE_NEON
+#if defined(QT_HAVE_SSSE3)
     // from qimage_ssse3.cpp
     Q_GUI_EXPORT void QT_FASTCALL qt_convert_rgb888_to_rgb32_ssse3(quint32 *dst, const uchar *src, int len);
 
diff --git a/src/gui/kernel/qevent.cpp b/src/gui/kernel/qevent.cpp
index bbc9e0b..eade02e 100644
--- a/src/gui/kernel/qevent.cpp
+++ b/src/gui/kernel/qevent.cpp
@@ -4281,6 +4281,11 @@ QTouchEvent::TouchPoint &QTouchEvent::TouchPoint::operator=(const QTouchEvent::T
     QGestureEvent::accept() for each of them, or an event filter consumes the
     event.
 
+    \section1 Further Reading
+
+    For an overview of gesture handling in Qt and information on using gestures
+    in your applications, see the \l{Gestures Programming} document.
+
     \sa QGesture, QGestureRecognizer,
         QWidget::grabGesture(), QGraphicsObject::grabGesture()
 */
diff --git a/src/gui/kernel/qgesture.cpp b/src/gui/kernel/qgesture.cpp
index 4a4452a..13274c4 100644
--- a/src/gui/kernel/qgesture.cpp
+++ b/src/gui/kernel/qgesture.cpp
@@ -59,6 +59,9 @@ QT_BEGIN_NAMESPACE
     the QGestureRecognizer object that is registered with the application; see
     QGestureRecognizer::registerRecognizer().
 
+    For an overview of gesture handling in Qt and information on using gestures
+    in your applications, see the \l{Gestures Programming} document.
+
     \section1 Gesture Properties
 
     The class has a list of properties that can be queried by the user to get
@@ -219,7 +222,10 @@ QGesture::GestureCancelPolicy QGesture::gestureCancelPolicy() const
 
     \image pangesture.png
 
-    \sa {Gestures Programming}, QPinchGesture, QSwipeGesture
+    For an overview of gesture handling in Qt and information on using gestures
+    in your applications, see the \l{Gestures Programming} document.
+
+    \sa QPinchGesture, QSwipeGesture
 */
 
 /*!
@@ -314,6 +320,9 @@ void QPanGesture::setAcceleration(qreal value)
     them closer together or further apart to change the scale factor, zoom, or level
     of detail of the user interface.
 
+    For an overview of gesture handling in Qt and information on using gestures
+    in your applications, see the \l{Gestures Programming} document.
+
     \image pinchgesture.png
 
     Instead of repeatedly applying the same pinching gesture, the user may
@@ -322,7 +331,7 @@ void QPanGesture::setAcceleration(qreal value)
     will continue to be delivered to the target object, containing an instance
     of QPinchGesture in the Qt::GestureUpdated state.
 
-    \sa {Gestures Programming}, QPanGesture, QSwipeGesture
+    \sa QPanGesture, QSwipeGesture
 */
 
 /*!
@@ -572,7 +581,10 @@ void QPinchGesture::setRotationAngle(qreal value)
 
     \image swipegesture.png
 
-    \sa {Gestures Programming}, QPanGesture, QPinchGesture
+    For an overview of gesture handling in Qt and information on using gestures
+    in your applications, see the \l{Gestures Programming} document.
+
+    \sa QPanGesture, QPinchGesture
 */
 
 /*!
@@ -667,7 +679,10 @@ void QSwipeGesture::setSwipeAngle(qreal value)
     \brief The QTapGesture class describes a tap gesture made by the user.
     \ingroup gestures
 
-    \sa {Gestures Programming}, QPanGesture, QPinchGesture
+    For an overview of gesture handling in Qt and information on using gestures
+    in your applications, see the \l{Gestures Programming} document.
+
+    \sa QPanGesture, QPinchGesture
 */
 
 /*!
@@ -700,7 +715,10 @@ void QTapGesture::setPosition(const QPointF &value)
     gesture made by the user.
     \ingroup gestures
 
-    \sa {Gestures Programming}, QPanGesture, QPinchGesture
+    For an overview of gesture handling in Qt and information on using gestures
+    in your applications, see the \l{Gestures Programming} document.
+
+    \sa QPanGesture, QPinchGesture
 */
 
 /*!
diff --git a/src/gui/kernel/qgesturerecognizer.cpp b/src/gui/kernel/qgesturerecognizer.cpp
index 3e23bbf..e0e7784 100644
--- a/src/gui/kernel/qgesturerecognizer.cpp
+++ b/src/gui/kernel/qgesturerecognizer.cpp
@@ -62,6 +62,9 @@ QT_BEGIN_NAMESPACE
    need to use this class directly. Instances will be created behind the scenes by the
    framework.
 
+   For an overview of gesture handling in Qt and information on using gestures
+   in your applications, see the \l{Gestures Programming} document.
+
    \section1 Recognizing Gestures
 
    The process of recognizing gestures involves filtering input events sent to specific
diff --git a/src/gui/painting/painting.pri b/src/gui/painting/painting.pri
index 4023f65..dfa4a48 100644
--- a/src/gui/painting/painting.pri
+++ b/src/gui/painting/painting.pri
@@ -246,23 +246,8 @@ symbian {
         QMAKE_CXXFLAGS.ARMCC *= -O3
 }
 
-neon:*-g++* {
-    DEFINES += QT_HAVE_NEON
-    HEADERS += painting/qdrawhelper_neon_p.h
-    SOURCES += painting/qdrawhelper_neon.cpp
-    QMAKE_CXXFLAGS *= -mfpu=neon
-
-    DRAWHELPER_NEON_ASM_FILES = ../3rdparty/pixman/pixman-arm-neon-asm.S painting/qdrawhelper_neon_asm.S
-
-    neon_compiler.commands = $$QMAKE_CXX -c
-    neon_compiler.commands += $(CXXFLAGS) $(INCPATH) ${QMAKE_FILE_IN} -o ${QMAKE_FILE_OUT}
-    neon_compiler.dependency_type = TYPE_C
-    neon_compiler.output = ${QMAKE_VAR_OBJECTS_DIR}${QMAKE_FILE_BASE}$${first(QMAKE_EXT_OBJ)}
-    neon_compiler.input = DRAWHELPER_NEON_ASM_FILES
-    neon_compiler.variable_out = OBJECTS
-    neon_compiler.name = compiling[neon] ${QMAKE_FILE_IN}
-    silent:neon_compiler.commands = @echo compiling[neon] ${QMAKE_FILE_IN} && $$neon_compiler.commands
-    QMAKE_EXTRA_COMPILERS += neon_compiler
-}
+NEON_SOURCES += painting/qdrawhelper_neon.cpp
+NEON_HEADERS += painting/qdrawhelper_neon_p.h
+NEON_ASM += ../3rdparty/pixman/pixman-arm-neon-asm.S painting/qdrawhelper_neon_asm.S
 
 include($$PWD/../../3rdparty/zlib_dependency.pri)
diff --git a/src/gui/painting/qdrawhelper_sse2.cpp b/src/gui/painting/qdrawhelper_sse2.cpp
index 7ab9eda..22c0384 100644
--- a/src/gui/painting/qdrawhelper_sse2.cpp
+++ b/src/gui/painting/qdrawhelper_sse2.cpp
@@ -112,9 +112,7 @@ void qt_blend_rgb32_on_rgb32_sse2(uchar *destPixels, int dbpl,
                 int x = 0;
 
                 // First, align dest to 16 bytes:
-                const int offsetToAlignOn16Bytes = (4 - ((reinterpret_cast<quintptr>(dst) >> 2) & 0x3)) & 0x3;
-                const int prologLength = qMin(w, offsetToAlignOn16Bytes);
-                for (; x < prologLength; ++x) {
+                ALIGNMENT_PROLOGUE_16BYTES(dst, x, w) {
                     quint32 s = src[x];
                     s = BYTE_MUL(s, const_alpha);
                     dst[x] = INTERPOLATE_PIXEL_255(src[x], const_alpha, dst[x], one_minus_const_alpha);
@@ -182,12 +180,10 @@ inline int comp_func_Plus_one_pixel(uint d, const uint s)
 void QT_FASTCALL comp_func_Plus_sse2(uint *dst, const uint *src, int length, uint const_alpha)
 {
     int x = 0;
-    const int offsetToAlignOn16Bytes = (4 - ((reinterpret_cast<quintptr>(dst) >> 2) & 0x3)) & 0x3;
-    const int prologLength = qMin(length, offsetToAlignOn16Bytes);
 
     if (const_alpha == 255) {
         // 1) Prologue: align destination on 16 bytes
-        for (; x < prologLength; ++x)
+        ALIGNMENT_PROLOGUE_16BYTES(dst, x, length)
             dst[x] = comp_func_Plus_one_pixel(dst[x], src[x]);
 
         // 2) composition with SSE2
@@ -208,7 +204,7 @@ void QT_FASTCALL comp_func_Plus_sse2(uint *dst, const uint *src, int length, uin
         const __m128i oneMinusConstAlpha =  _mm_set1_epi16(one_minus_const_alpha);
 
         // 1) Prologue: align destination on 16 bytes
-        for (; x < prologLength; ++x)
+        ALIGNMENT_PROLOGUE_16BYTES(dst, x, length)
             dst[x] = comp_func_Plus_one_pixel_const_alpha(dst[x], src[x], const_alpha, one_minus_const_alpha);
 
         const __m128i half = _mm_set1_epi16(0x80);
@@ -239,9 +235,7 @@ void QT_FASTCALL comp_func_Source_sse2(uint *dst, const uint *src, int length, u
         int x = 0;
 
         // 1) prologue, align on 16 bytes
-        const int offsetToAlignOn16Bytes = (4 - ((reinterpret_cast<quintptr>(dst) >> 2) & 0x3)) & 0x3;
-        const int prologLength = qMin(length, offsetToAlignOn16Bytes);
-        for (; x < prologLength; ++x)
+        ALIGNMENT_PROLOGUE_16BYTES(dst, x, length)
             dst[x] = INTERPOLATE_PIXEL_255(src[x], const_alpha, dst[x], ialpha);
 
         // 2) interpolate pixels with SSE2
diff --git a/src/gui/painting/qdrawingprimitive_sse2_p.h b/src/gui/painting/qdrawingprimitive_sse2_p.h
index 18355c2..d8f6bf5 100644
--- a/src/gui/painting/qdrawingprimitive_sse2_p.h
+++ b/src/gui/painting/qdrawingprimitive_sse2_p.h
@@ -143,9 +143,7 @@ QT_BEGIN_NAMESPACE
     int x = 0; \
 \
     /* First, get dst aligned. */ \
-    const int offsetToAlignOn16Bytes = (4 - ((reinterpret_cast<quintptr>(dst) >> 2) & 0x3)) & 0x3;\
-    const int prologLength = qMin(length, offsetToAlignOn16Bytes);\
-    for (; x < prologLength; ++x) { \
+    ALIGNMENT_PROLOGUE_16BYTES(dst, x, length) { \
         uint s = src[x]; \
         if (s >= 0xff000000) \
             dst[x] = s; \
@@ -202,9 +200,7 @@ QT_BEGIN_NAMESPACE
 { \
     int x = 0; \
 \
-    const int offsetToAlignOn16Bytes = (4 - ((reinterpret_cast<quintptr>(dst) >> 2) & 0x3)) & 0x3;\
-    const int prologLength = qMin(length, offsetToAlignOn16Bytes);\
-    for (; x < prologLength; ++x) { \
+    ALIGNMENT_PROLOGUE_16BYTES(dst, x, length) { \
         quint32 s = src[x]; \
         if (s != 0) { \
             s = BYTE_MUL(s, const_alpha); \
diff --git a/src/gui/painting/qpainter.cpp b/src/gui/painting/qpainter.cpp
index 9dadbd5..b694d9c 100644
--- a/src/gui/painting/qpainter.cpp
+++ b/src/gui/painting/qpainter.cpp
@@ -90,6 +90,15 @@ void qt_format_text(const QFont &font,
                     const QRectF &_r, int tf, const QTextOption *option, const QString& str, QRectF *brect,
                     int tabstops, int* tabarray, int tabarraylen,
                     QPainter *painter);
+static void drawTextItemDecoration(QPainter *painter, const QPointF &pos, const QFontEngine *fe,
+                                   QTextCharFormat::UnderlineStyle underlineStyle,
+                                   const QTextItem::RenderFlags flags, qreal width,
+                                   const QTextCharFormat &charFormat);
+// Helper function to calculate left most position, width and flags for decoration drawing
+static void drawDecorationForGlyphs(QPainter *painter, const glyph_t *glyphArray,
+                                    const QFixedPoint *positions, int glyphCount,
+                                    QFontEngine *fontEngine, const QFont &font,
+                                    const QTextCharFormat &charFormat);
 
 static inline QGradient::CoordinateMode coordinateMode(const QBrush &brush)
 {
@@ -5923,6 +5932,10 @@ void QPainter::drawStaticText(const QPointF &topLeftPosition, const QStaticText
             currentColor = item->color;
         }
         d->extended->drawStaticTextItem(item);
+
+        drawDecorationForGlyphs(this, item->glyphs, item->glyphPositions,
+                                item->numGlyphs, item->fontEngine, staticText_d->font,
+                                QTextCharFormat());
     }
     if (currentColor != oldPen.color())
         setPen(oldPen);
@@ -6290,15 +6303,15 @@ static QPixmap generateWavyPixmap(qreal maxRadius, const QPen &pen)
     return pixmap;
 }
 
-static void drawTextItemDecoration(QPainter *painter, const QPointF &pos, const QTextItemInt &ti)
+static void drawTextItemDecoration(QPainter *painter, const QPointF &pos, const QFontEngine *fe,
+                                   QTextCharFormat::UnderlineStyle underlineStyle,
+                                   const QTextItem::RenderFlags flags, qreal width,
+                                   const QTextCharFormat &charFormat)
 {
-    QTextCharFormat::UnderlineStyle underlineStyle = ti.underlineStyle;
     if (underlineStyle == QTextCharFormat::NoUnderline
-        && !(ti.flags & (QTextItem::StrikeOut | QTextItem::Overline)))
+        && !(flags & (QTextItem::StrikeOut | QTextItem::Overline)))
         return;
 
-    QFontEngine *fe = ti.fontEngine;
-
     const QPen oldPen = painter->pen();
     const QBrush oldBrush = painter->brush();
     painter->setBrush(Qt::NoBrush);
@@ -6307,7 +6320,7 @@ static void drawTextItemDecoration(QPainter *painter, const QPointF &pos, const
     pen.setWidthF(fe->lineThickness().toReal());
     pen.setCapStyle(Qt::FlatCap);
 
-    QLineF line(pos.x(), pos.y(), pos.x() + ti.width.toReal(), pos.y());
+    QLineF line(pos.x(), pos.y(), pos.x() + width, pos.y());
 
     const qreal underlineOffset = fe->underlinePosition().toReal();
     // deliberately ceil the offset to avoid the underline coming too close to
@@ -6322,21 +6335,21 @@ static void drawTextItemDecoration(QPainter *painter, const QPointF &pos, const
         painter->save();
         painter->translate(0, pos.y() + 1);
 
-        QColor uc = ti.charFormat.underlineColor();
+        QColor uc = charFormat.underlineColor();
         if (uc.isValid())
             pen.setColor(uc);
 
         // Adapt wave to underlineOffset or pen width, whatever is larger, to make it work on all platforms
         const QPixmap wave = generateWavyPixmap(qMax(underlineOffset, pen.widthF()), pen);
-        const int descent = (int) ti.descent.toReal();
+        const int descent = (int) fe->descent().toReal();
 
         painter->setBrushOrigin(painter->brushOrigin().x(), 0);
-        painter->fillRect(pos.x(), 0, qCeil(ti.width.toReal()), qMin(wave.height(), descent), wave);
+        painter->fillRect(pos.x(), 0, qCeil(width), qMin(wave.height(), descent), wave);
         painter->restore();
     } else if (underlineStyle != QTextCharFormat::NoUnderline) {
         QLineF underLine(line.x1(), underlinePos, line.x2(), underlinePos);
 
-        QColor uc = ti.charFormat.underlineColor();
+        QColor uc = charFormat.underlineColor();
         if (uc.isValid())
             pen.setColor(uc);
 
@@ -6348,14 +6361,14 @@ static void drawTextItemDecoration(QPainter *painter, const QPointF &pos, const
     pen.setStyle(Qt::SolidLine);
     pen.setColor(oldPen.color());
 
-    if (ti.flags & QTextItem::StrikeOut) {
+    if (flags & QTextItem::StrikeOut) {
         QLineF strikeOutLine = line;
         strikeOutLine.translate(0., - fe->ascent().toReal() / 3.);
         painter->setPen(pen);
         painter->drawLine(strikeOutLine);
     }
 
-    if (ti.flags & QTextItem::Overline) {
+    if (flags & QTextItem::Overline) {
         QLineF overLine = line;
         overLine.translate(0., - fe->ascent().toReal());
         painter->setPen(pen);
@@ -6366,6 +6379,50 @@ static void drawTextItemDecoration(QPainter *painter, const QPointF &pos, const
     painter->setBrush(oldBrush);
 }
 
+static void drawDecorationForGlyphs(QPainter *painter, const glyph_t *glyphArray,
+                                    const QFixedPoint *positions, int glyphCount,
+                                    QFontEngine *fontEngine, const QFont &font,
+                                    const QTextCharFormat &charFormat)
+{
+    if (!(font.underline() || font.strikeOut() || font.overline()))
+        return;
+
+    QFixed leftMost;
+    QFixed rightMost;
+    QFixed baseLine;
+    for (int i=0; i<glyphCount; ++i) {
+        glyph_metrics_t gm = fontEngine->boundingBox(glyphArray[i]);
+        if (i == 0 || leftMost > positions[i].x)
+            leftMost = positions[i].x;
+
+        // We don't support glyphs that do not share a common baseline. If this turns out to
+        // be a relevant use case, then we need to find clusters of glyphs that share a baseline
+        // and do a drawTextItemDecorations call per cluster.
+        if (i == 0 || baseLine < positions[i].y)
+            baseLine = positions[i].y;
+
+        // We use the advance rather than the actual bounds to match the algorithm in drawText()
+        if (i == 0 || rightMost < positions[i].x + gm.xoff)
+            rightMost = positions[i].x + gm.xoff;
+    }
+
+    QFixed width = rightMost - leftMost;
+    QTextItem::RenderFlags flags = 0;
+
+    if (font.underline())
+        flags |= QTextItem::Underline;
+    if (font.overline())
+        flags |= QTextItem::Overline;
+    if (font.strikeOut())
+        flags |= QTextItem::StrikeOut;
+
+    drawTextItemDecoration(painter, QPointF(leftMost.toReal(), baseLine.toReal()),
+                           fontEngine,
+                           font.underline() ? QTextCharFormat::SingleUnderline
+                                            : QTextCharFormat::NoUnderline, flags,
+                           width.toReal(), charFormat);
+}
+
 void QPainter::drawTextItem(const QPointF &p, const QTextItem &_ti)
 {
 #ifdef QT_DEBUG_DRAW
@@ -6496,7 +6553,8 @@ void QPainter::drawTextItem(const QPointF &p, const QTextItem &_ti)
         else
             d->engine->drawTextItem(p, ti);
     }
-    drawTextItemDecoration(this, p, ti);
+    drawTextItemDecoration(this, p, ti.fontEngine, ti.underlineStyle, ti.flags, ti.width.toReal(),
+                           ti.charFormat);
 
     if (d->state->renderHints != oldRenderHints) {
         d->state->renderHints = oldRenderHints;
diff --git a/src/gui/text/qstatictext.cpp b/src/gui/text/qstatictext.cpp
index 7396bcd..21c2e02 100644
--- a/src/gui/text/qstatictext.cpp
+++ b/src/gui/text/qstatictext.cpp
@@ -109,10 +109,18 @@ QT_BEGIN_NAMESPACE
     QPainter::drawStaticText() and can change from call to call with a minimal impact on
     performance.
 
-    QStaticText will attempt to guess the format of the input text using Qt::mightBeRichText().
-    To force QStaticText to display its contents as either plain text or rich text, use the
-    function QStaticText::setTextFormat() and pass in, respectively, Qt::PlainText and
-    Qt::RichText.
+    For extra convenience, it is possible to apply formatting to the text using the HTML subset
+    supported by QTextDocument. QStaticText will attempt to guess the format of the input text using
+    Qt::mightBeRichText(), and interpret it as rich text if this function returns true. To force
+    QStaticText to display its contents as either plain text or rich text, use the function
+    QStaticText::setTextFormat() and pass in, respectively, Qt::PlainText and Qt::RichText.
+
+    QStaticText can only represent text, so only HTML tags which alter the layout or appearance of
+    the text will be respected. Adding an image to the input HTML, for instance, will cause the
+    image to be included as part of the layout, affecting the positions of the text glyphs, but it
+    will not be displayed. The result will be an empty area the size of the image in the output.
+    Similarly, using tables will cause the text to be laid out in table format, but the borders
+    will not be drawn.
 
     If it's the first time the static text is drawn, or if the static text, or the painter's font
     has been altered since the last time it was drawn, the text's layout has to be
diff --git a/src/gui/text/qtextengine.cpp b/src/gui/text/qtextengine.cpp
index 439f2a4..5670e29 100644
--- a/src/gui/text/qtextengine.cpp
+++ b/src/gui/text/qtextengine.cpp
@@ -923,6 +923,13 @@ void QTextEngine::shapeText(int item) const
         si.width += glyphs.advances_x[i];
 }
 
+static inline bool hasCaseChange(const QScriptItem &si)
+{
+    return si.analysis.flags == QScriptAnalysis::SmallCaps ||
+           si.analysis.flags == QScriptAnalysis::Uppercase ||
+           si.analysis.flags == QScriptAnalysis::Lowercase;
+}
+
 #if defined(Q_WS_WINCE) //TODO
 // set the glyph attributes heuristically. Assumes a 1 to 1 relationship between chars and glyphs
 // and no reordering.
@@ -1050,14 +1057,15 @@ void QTextEngine::shapeTextWithCE(int item) const
     if (option.useDesignMetrics())
 	flags |= DesignMetrics;
 
-    attributes(); // pre-initialize char attributes
+    // pre-initialize char attributes
+    if (! attributes())
+        return;
 
     const int len = length(item);
     int num_glyphs = length(item);
     const QChar *str = layoutData->string.unicode() + si.position;
     ushort upperCased[256];
-    if (si.analysis.flags == QScriptAnalysis::SmallCaps || si.analysis.flags == QScriptAnalysis::Uppercase
-            || si.analysis.flags == QScriptAnalysis::Lowercase) {
+    if (hasCaseChange(si)) {
         ushort *uc = upperCased;
         if (len > 256)
             uc = new ushort[len];
@@ -1071,7 +1079,14 @@ void QTextEngine::shapeTextWithCE(int item) const
     }
 
     while (true) {
-        ensureSpace(num_glyphs);
+        if (! ensureSpace(num_glyphs)) {
+            // If str is converted to uppercase/lowercase form with a new buffer,
+            // we need to delete that buffer before return for error
+            const ushort *uc = reinterpret_cast<const ushort *>(str);
+            if (hasCaseChange(si) && uc != upperCased)
+                delete [] uc;
+            return;
+        }
         num_glyphs = layoutData->glyphLayout.numGlyphs - layoutData->used;
 
         QGlyphLayout g = availableGlyphs(&si);
@@ -1092,9 +1107,7 @@ void QTextEngine::shapeTextWithCE(int item) const
     layoutData->used += si.num_glyphs;
 
     const ushort *uc = reinterpret_cast<const ushort *>(str);
-    if ((si.analysis.flags == QScriptAnalysis::SmallCaps || si.analysis.flags == QScriptAnalysis::Uppercase
-         || si.analysis.flags == QScriptAnalysis::Lowercase)
-        && uc != upperCased)
+    if (hasCaseChange(si) && uc != upperCased)
         delete [] uc;
 }
 #endif
@@ -1133,8 +1146,7 @@ void QTextEngine::shapeTextWithHarfbuzz(int item) const
     entire_shaper_item.item.bidiLevel = si.analysis.bidiLevel;
 
     HB_UChar16 upperCased[256]; // XXX what about making this 4096, so we don't have to extend it ever.
-    if (si.analysis.flags == QScriptAnalysis::SmallCaps || si.analysis.flags == QScriptAnalysis::Uppercase
-            || si.analysis.flags == QScriptAnalysis::Lowercase) {
+    if (hasCaseChange(si)) {
         HB_UChar16 *uc = upperCased;
         if (entire_shaper_item.item.length > 256)
             uc = new HB_UChar16[entire_shaper_item.item.length];
@@ -1156,17 +1168,24 @@ void QTextEngine::shapeTextWithHarfbuzz(int item) const
         entire_shaper_item.shaperFlags |= HB_ShaperFlag_UseDesignMetrics;
 
     entire_shaper_item.num_glyphs = qMax(layoutData->glyphLayout.numGlyphs - layoutData->used, int(entire_shaper_item.item.length));
-    ensureSpace(entire_shaper_item.num_glyphs);
+    if (! ensureSpace(entire_shaper_item.num_glyphs)) {
+        if (hasCaseChange(si))
+            delete [] const_cast<HB_UChar16 *>(entire_shaper_item.string);
+        return;
+    }
     QGlyphLayout initialGlyphs = availableGlyphs(&si).mid(0, entire_shaper_item.num_glyphs);
 
     if (!stringToGlyphs(&entire_shaper_item, &initialGlyphs, font)) {
-        ensureSpace(entire_shaper_item.num_glyphs);
+        if (! ensureSpace(entire_shaper_item.num_glyphs)) {
+            if (hasCaseChange(si))
+                delete [] const_cast<HB_UChar16 *>(entire_shaper_item.string);
+            return;
+        }
         initialGlyphs = availableGlyphs(&si).mid(0, entire_shaper_item.num_glyphs);
 
         if (!stringToGlyphs(&entire_shaper_item, &initialGlyphs, font)) {
             // ############ if this happens there's a bug in the fontengine
-            if ((si.analysis.flags == QScriptAnalysis::SmallCaps || si.analysis.flags == QScriptAnalysis::Uppercase
-                    || si.analysis.flags == QScriptAnalysis::Lowercase) && entire_shaper_item.string != upperCased)
+            if (hasCaseChange(si) && entire_shaper_item.string != upperCased)
                 delete [] const_cast<HB_UChar16 *>(entire_shaper_item.string);
             return;
         }
@@ -1231,7 +1250,11 @@ void QTextEngine::shapeTextWithHarfbuzz(int item) const
         remaining_glyphs -= shaper_item.initialGlyphCount;
 
         do {
-            ensureSpace(glyph_pos + shaper_item.num_glyphs + remaining_glyphs);
+            if (! ensureSpace(glyph_pos + shaper_item.num_glyphs + remaining_glyphs)) {
+                if (hasCaseChange(si))
+                    delete [] const_cast<HB_UChar16 *>(entire_shaper_item.string);
+                return;
+            }
 
             const QGlyphLayout g = availableGlyphs(&si).mid(glyph_pos);
             moveGlyphData(g.mid(shaper_item.num_glyphs), g.mid(shaper_item.initialGlyphCount), remaining_glyphs);
@@ -1271,8 +1294,7 @@ void QTextEngine::shapeTextWithHarfbuzz(int item) const
 
     layoutData->used += si.num_glyphs;
 
-    if ((si.analysis.flags == QScriptAnalysis::SmallCaps || si.analysis.flags == QScriptAnalysis::Uppercase)
-        && entire_shaper_item.string != upperCased)
+    if (hasCaseChange(si) && entire_shaper_item.string != upperCased)
         delete [] const_cast<HB_UChar16 *>(entire_shaper_item.string);
 }
 
@@ -1317,7 +1339,8 @@ const HB_CharAttributes *QTextEngine::attributes() const
         return (HB_CharAttributes *) layoutData->memory;
 
     itemize();
-    ensureSpace(layoutData->string.length());
+    if (! ensureSpace(layoutData->string.length()))
+        return NULL;
 
     QVarLengthArray<HB_ScriptItem> hbScriptItems(layoutData->items.size());
 
@@ -1864,7 +1887,10 @@ void QTextEngine::justify(const QScriptLine &line)
 
     // don't include trailing white spaces when doing justification
     int line_length = line.length;
-    const HB_CharAttributes *a = attributes()+line.from;
+    const HB_CharAttributes *a = attributes();
+    if (! a)
+        return;
+    a += line.from;
     while (line_length && a[line_length-1].whiteSpace)
         --line_length;
     // subtract one char more, as we can't justfy after the last character
@@ -2045,7 +2071,7 @@ QTextEngine::LayoutData::LayoutData()
     memory_on_stack = false;
     used = 0;
     hasBidi = false;
-    inLayout = false;
+    layoutState = LayoutEmpty;
     haveCharAttributes = false;
     logClustersPtr = 0;
     available_glyphs = 0;
@@ -2079,7 +2105,7 @@ QTextEngine::LayoutData::LayoutData(const QString &str, void **stack_memory, int
     }
     used = 0;
     hasBidi = false;
-    inLayout = false;
+    layoutState = LayoutEmpty;
     haveCharAttributes = false;
 }
 
@@ -2090,12 +2116,12 @@ QTextEngine::LayoutData::~LayoutData()
     memory = 0;
 }
 
-void QTextEngine::LayoutData::reallocate(int totalGlyphs)
+bool QTextEngine::LayoutData::reallocate(int totalGlyphs)
 {
     Q_ASSERT(totalGlyphs >= glyphLayout.numGlyphs);
     if (memory_on_stack && available_glyphs >= totalGlyphs) {
         glyphLayout.grow(glyphLayout.data(), totalGlyphs);
-        return;
+        return true;
     }
 
     int space_charAttributes = sizeof(HB_CharAttributes)*string.length()/sizeof(void*) + 1;
@@ -2103,7 +2129,14 @@ void QTextEngine::LayoutData::reallocate(int totalGlyphs)
     int space_glyphs = QGlyphLayout::spaceNeededForGlyphLayout(totalGlyphs)/sizeof(void*) + 2;
 
     int newAllocated = space_charAttributes + space_glyphs + space_logClusters;
-    Q_ASSERT(newAllocated >= allocated);
+    // These values can be negative if the length of string/glyphs causes overflow,
+    // we can't layout such a long string all at once, so return false here to
+    // indicate there is a failure
+    if (space_charAttributes < 0 || space_logClusters < 0 || space_glyphs < 0 || newAllocated < allocated) {
+        layoutState = LayoutFailed;
+        return false;
+    }
+
     void **newMem = memory;
     newMem = (void **)::realloc(memory_on_stack ? 0 : memory, newAllocated*sizeof(void *));
     Q_CHECK_PTR(newMem);
@@ -2124,6 +2157,7 @@ void QTextEngine::LayoutData::reallocate(int totalGlyphs)
     glyphLayout.grow(reinterpret_cast<char *>(m), totalGlyphs);
 
     allocated = newAllocated;
+    return true;
 }
 
 // grow to the new size, copying the existing data to the new layout
@@ -2155,7 +2189,7 @@ void QTextEngine::freeMemory()
     } else {
         layoutData->used = 0;
         layoutData->hasBidi = false;
-        layoutData->inLayout = false;
+        layoutData->layoutState = LayoutEmpty;
         layoutData->haveCharAttributes = false;
     }
     for (int i = 0; i < lines.size(); ++i) {
@@ -2314,6 +2348,9 @@ QString QTextEngine::elidedText(Qt::TextElideMode mode, const QFixed &width, int
                 shape(i);
 
             HB_CharAttributes *attributes = const_cast<HB_CharAttributes *>(this->attributes());
+            if (!attributes)
+                return QString();
+
             unsigned short *logClusters = this->logClusters(&si);
             QGlyphLayout glyphs = shapedGlyphs(&si);
 
@@ -2385,6 +2422,8 @@ QString QTextEngine::elidedText(Qt::TextElideMode mode, const QFixed &width, int
         return QString();
 
     const HB_CharAttributes *attributes = this->attributes();
+    if (!attributes)
+        return QString();
 
     if (mode == Qt::ElideRight) {
         QFixed currentWidth;
diff --git a/src/gui/text/qtextengine_p.h b/src/gui/text/qtextengine_p.h
index e623fa5..4cbe81f 100644
--- a/src/gui/text/qtextengine_p.h
+++ b/src/gui/text/qtextengine_p.h
@@ -416,6 +416,11 @@ class QTextFormatCollection;
 
 class Q_GUI_EXPORT QTextEngine {
 public:
+    enum LayoutState {
+        LayoutEmpty,
+        InLayout,
+        LayoutFailed,
+    };
     struct LayoutData {
         LayoutData(const QString &str, void **stack_memory, int mem_size);
         LayoutData();
@@ -428,11 +433,11 @@ public:
         QGlyphLayout glyphLayout;
         mutable int used;
         uint hasBidi : 1;
-        uint inLayout : 1;
+        uint layoutState : 2;
         uint memory_on_stack : 1;
         bool haveCharAttributes;
         QString string;
-        void reallocate(int totalGlyphs);
+        bool reallocate(int totalGlyphs);
     };
 
     QTextEngine(LayoutData *data);
@@ -520,9 +525,10 @@ public:
         return layoutData->glyphLayout.mid(si->glyph_data_offset, si->num_glyphs);
     }
 
-    inline void ensureSpace(int nGlyphs) const {
+    inline bool ensureSpace(int nGlyphs) const {
         if (layoutData->glyphLayout.numGlyphs - layoutData->used < nGlyphs)
-            layoutData->reallocate((((layoutData->used + nGlyphs)*3/2 + 15) >> 4) << 4);
+            return layoutData->reallocate((((layoutData->used + nGlyphs)*3/2 + 15) >> 4) << 4);
+        return true;
     }
 
     void freeMemory();
diff --git a/src/gui/text/qtextlayout.cpp b/src/gui/text/qtextlayout.cpp
index 674064e..da43913 100644
--- a/src/gui/text/qtextlayout.cpp
+++ b/src/gui/text/qtextlayout.cpp
@@ -74,6 +74,8 @@ static inline QFixed leadingSpaceWidth(QTextEngine *eng, const QScriptLine &line
 
     int pos = line.length;
     const HB_CharAttributes *attributes = eng->attributes();
+    if (!attributes)
+        return QFixed();
     while (pos > 0 && attributes[line.from + pos - 1].whiteSpace)
         --pos;
     return eng->width(line.from + pos, line.length - pos);
@@ -601,7 +603,7 @@ bool QTextLayout::cacheEnabled() const
 void QTextLayout::beginLayout()
 {
 #ifndef QT_NO_DEBUG
-    if (d->layoutData && d->layoutData->inLayout) {
+    if (d->layoutData && d->layoutData->layoutState == QTextEngine::InLayout) {
         qWarning("QTextLayout::beginLayout: Called while already doing layout");
         return;
     }
@@ -609,7 +611,7 @@ void QTextLayout::beginLayout()
     d->invalidate();
     d->clearLineData();
     d->itemize();
-    d->layoutData->inLayout = true;
+    d->layoutData->layoutState = QTextEngine::InLayout;
 }
 
 /*!
@@ -618,7 +620,7 @@ void QTextLayout::beginLayout()
 void QTextLayout::endLayout()
 {
 #ifndef QT_NO_DEBUG
-    if (!d->layoutData || !d->layoutData->inLayout) {
+    if (!d->layoutData || d->layoutData->layoutState == QTextEngine::LayoutEmpty) {
         qWarning("QTextLayout::endLayout: Called without beginLayout()");
         return;
     }
@@ -627,7 +629,7 @@ void QTextLayout::endLayout()
     if (l && d->lines.at(l-1).length < 0) {
         QTextLine(l-1, d).setNumColumns(INT_MAX);
     }
-    d->layoutData->inLayout = false;
+    d->layoutData->layoutState = QTextEngine::LayoutEmpty;
     if (!d->cacheGlyphs)
         d->freeMemory();
 }
@@ -757,11 +759,14 @@ bool QTextLayout::isValidCursorPosition(int pos) const
 QTextLine QTextLayout::createLine()
 {
 #ifndef QT_NO_DEBUG
-    if (!d->layoutData || !d->layoutData->inLayout) {
+    if (!d->layoutData || d->layoutData->layoutState == QTextEngine::LayoutEmpty) {
         qWarning("QTextLayout::createLine: Called without layouting");
         return QTextLine();
     }
 #endif
+    if (d->layoutData->layoutState == QTextEngine::LayoutFailed)
+        return QTextLine();
+
     int l = d->lines.size();
     if (l && d->lines.at(l-1).length < 0) {
         QTextLine(l-1, d).setNumColumns(INT_MAX);
@@ -1704,14 +1709,18 @@ namespace {
             return glyphs.glyphs[logClusters[currentPosition - 1]];
         }
 
+        inline void adjustRightBearing(glyph_t glyph)
+        {
+            qreal rb;
+            fontEngine->getGlyphBearings(glyph, 0, &rb);
+            rightBearing = qMin(QFixed(), QFixed::fromReal(rb));
+        }
+
         inline void adjustRightBearing()
         {
             if (currentPosition <= 0)
                 return;
-
-            qreal rb;
-            fontEngine->getGlyphBearings(currentGlyph(), 0, &rb);
-            rightBearing = qMin(QFixed(), QFixed::fromReal(rb));
+            adjustRightBearing(currentGlyph());
         }
 
         inline void resetRightBearing()
@@ -1801,6 +1810,8 @@ void QTextLine::layout_helper(int maxGlyphs)
     Qt::Alignment alignment = eng->option.alignment();
 
     const HB_CharAttributes *attributes = eng->attributes();
+    if (!attributes)
+        return;
     lbh.currentPosition = line.from;
     int end = 0;
     lbh.logClusters = eng->layoutData->logClustersPtr;
@@ -1814,6 +1825,8 @@ void QTextLine::layout_helper(int maxGlyphs)
             if (!current.num_glyphs) {
                 eng->shape(item);
                 attributes = eng->attributes();
+                if (!attributes)
+                    return;
                 lbh.logClusters = eng->layoutData->logClustersPtr;
             }
             lbh.currentPosition = qMax(line.from, current.position);
@@ -1892,6 +1905,9 @@ void QTextLine::layout_helper(int maxGlyphs)
         } else {
             lbh.whiteSpaceOrObject = false;
             bool sb_or_ws = false;
+            glyph_t previousGlyph = 0;
+            if (lbh.currentPosition > 0 && lbh.logClusters[lbh.currentPosition - 1] <lbh.glyphs.numGlyphs)
+                previousGlyph = lbh.currentGlyph(); // needed to calculate right bearing later
             do {
                 addNextCluster(lbh.currentPosition, end, lbh.tmpData, lbh.glyphCount,
                                current, lbh.logClusters, lbh.glyphs);
@@ -1935,9 +1951,15 @@ void QTextLine::layout_helper(int maxGlyphs)
             // We ignore the right bearing if the minimum negative bearing is too little to
             // expand the text beyond the edge.
             if (sb_or_ws|breakany) {
+                QFixed rightBearing = lbh.rightBearing; // store previous right bearing
                 if (lbh.calculateNewWidth(line) - lbh.minimumRightBearing > line.width)
                     lbh.adjustRightBearing();
                 if (lbh.checkFullOtherwiseExtend(line)) {
+                    // we are too wide, fix right bearing
+                    if (rightBearing <= 0)
+                        lbh.rightBearing = rightBearing; // take from cache
+                    else if (previousGlyph > 0)
+                        lbh.adjustRightBearing(previousGlyph);
                     if (!breakany) {
                         line.textWidth += lbh.softHyphenWidth;
                     }