diff -urN 20161021/dist/changes-5.7.1 qtdeclarative-opensource-src-5.7.1/dist/changes-5.7.1
--- 20161021/dist/changes-5.7.1	1970-01-01 02:00:00.000000000 +0200
+++ qtdeclarative-opensource-src-5.7.1/dist/changes-5.7.1	2016-11-11 08:18:01.000000000 +0200
@@ -0,0 +1,64 @@
+Qt 5.7.1 is a bug-fix release. It maintains both forward and backward
+compatibility (source and binary) with Qt 5.7.0.
+
+For more details, refer to the online documentation included in this
+distribution. The documentation is also available online:
+
+http://doc.qt.io/qt-5/index.html
+
+The Qt version 5.7 series is binary compatible with the 5.6.x series.
+Applications compiled for 5.6 will continue to run with 5.7.
+
+Some of the changes listed in this file include issue tracking numbers
+corresponding to tasks in the Qt Bug Tracker:
+
+https://bugreports.qt.io/
+
+Each of these identifiers can be entered in the bug tracker to obtain more
+information about a particular change.
+
+****************************************************************************
+*                   Important Behavior Changes                             *
+****************************************************************************
+
+ - [QTBUG-55935] AnimatedSprite will no longer cause scenegraph updates when not
+   visible
+ - [QTBUG-46263] Fix QObjects becoming undefined when used in multiple QML
+   engines
+ - [QTBUG-54238] qt.scenegraph.info logging category got renamed to
+   qt.scenegraph.general.
+ - [QTBUG-50592] QVariants (e.g. QUrl) will now be better handled by
+   JSON.stringify
+ - [QTBUG-37095] Canvas now properly supports high-DPI screens
+ - QQuickWidget now properly repaints text on high-DPI screen changes.
+
+****************************************************************************
+*                          Library                                         *
+****************************************************************************
+
+QtQml
+-----
+
+ - [QTBUG-53412] Fix mapping of null JS values to null SQL values instead
+   of empty strings.
+ - [QTBUG-53794] Fix crash when using the "with" statement with an
+   expression that throws an exception.
+ - [QTBUG-54589] Fix assertion when deleting properties of JS objects
+ - [QTBUG-56658] Fix a crash in the QML compiler
+ - [QTBUG-53672] Fix crash caused by passing 0 to Array.join
+
+QtQuick
+-------
+
+ - The relevant child item is now sent a hover event when the window
+   receives a QEnterEvent, making sure hovering is recognized without
+   waiting for mouse movement.
+ - The threaded scene graph renderer does not sleep up to one vsync
+   interval before the first frame anymore.
+ - [QTBUG-56056] Fix crash when cancelling a QQuickImageResponse
+ - [QTBUG-39888] Fix crash with QQuickItems created via JavaScript being
+   garbage collected sometimes when they're not assigned to a window.
+ - [QTBUG-31861] Item: Fixed issue with mouse button events being sent even
+   when they were disabled by setAcceptedMouseButtons.
+ - [QTBUG-52389] Text: Fixed clipping of glyphs that extend beyond font's em
+   square.
diff -urN 20161021/src/imports/particles/particles.pro qtdeclarative-opensource-src-5.7.1/src/imports/particles/particles.pro
--- 20161021/src/imports/particles/particles.pro	2016-10-05 20:32:12.000000000 +0300
+++ qtdeclarative-opensource-src-5.7.1/src/imports/particles/particles.pro	2016-11-11 08:18:01.000000000 +0200
@@ -3,6 +3,11 @@
 TARGETPATH = QtQuick/Particles.2
 IMPORT_VERSION = 2.0
 
+greaterThan(QT_GCC_MAJOR_VERSION, 5) {
+    # Our code is bad. Temporary workaround. Fixed in 5.8
+    QMAKE_CXXFLAGS += -fno-delete-null-pointer-checks -fno-lifetime-dse
+}
+
 SOURCES += \
     plugin.cpp
 
diff -urN 20161021/src/qml/jit/qv4isel_masm.cpp qtdeclarative-opensource-src-5.7.1/src/qml/jit/qv4isel_masm.cpp
--- 20161021/src/qml/jit/qv4isel_masm.cpp	2016-10-05 20:32:12.000000000 +0300
+++ qtdeclarative-opensource-src-5.7.1/src/qml/jit/qv4isel_masm.cpp	2016-11-11 08:18:01.000000000 +0200
@@ -971,7 +971,7 @@
                 tag = QV4::Value::Integer_Type_Internal;
                 break;
             default:
-                tag = QV4::Value::Undefined_Type;
+                tag = 31337; // bogus value
                 Q_UNREACHABLE();
             }
             _as->store32(Assembler::TrustedImm32(tag), addr);
@@ -1418,7 +1418,7 @@
             Address temp = _as->loadAddress(Assembler::ScratchRegister, s->cond);
             Address tag = temp;
             tag.offset += QV4::Value::tagOffset();
-            Assembler::Jump booleanConversion = _as->branch32(Assembler::NotEqual, tag, Assembler::TrustedImm32(QV4::Value::Boolean_Type));
+            Assembler::Jump booleanConversion = _as->branch32(Assembler::NotEqual, tag, Assembler::TrustedImm32(QV4::Value::Boolean_Type_Internal));
 
             Address data = temp;
             data.offset += QV4::Value::valueOffset();
@@ -1582,7 +1582,7 @@
                     tag = QV4::Value::Boolean_Type_Internal;
                     break;
                 default:
-                    tag = QV4::Value::Undefined_Type;
+                    tag = 31337; // bogus value
                     Q_UNREACHABLE();
                 }
                 _as->or64(Assembler::TrustedImm64(tag << 32),
diff -urN 20161021/src/qml/jsruntime/qv4arraydata.cpp qtdeclarative-opensource-src-5.7.1/src/qml/jsruntime/qv4arraydata.cpp
--- 20161021/src/qml/jsruntime/qv4arraydata.cpp	2016-10-05 20:32:12.000000000 +0300
+++ qtdeclarative-opensource-src-5.7.1/src/qml/jsruntime/qv4arraydata.cpp	2016-11-11 08:18:01.000000000 +0200
@@ -100,7 +100,7 @@
 static Q_ALWAYS_INLINE void storeValue(ReturnedValue *target, uint value)
 {
     Value v;
-    v.setTagValue(Value::fromReturnedValue(*target).tag(), value);
+    v.setEmpty(value);
     *target = v.asReturnedValue();
 }
 
@@ -189,6 +189,7 @@
     } else {
         sparse->sparse = new SparseArray;
         lastFree = &sparse->freeList;
+        storeValue(lastFree, 0);
         for (uint i = 0; i < toCopy; ++i) {
             if (!sparse->arrayData[i].isEmpty()) {
                 SparseArrayNode *n = sparse->sparse->insert(i);
@@ -209,6 +210,8 @@
         }
         storeValue(lastFree, UINT_MAX);
     }
+
+    Q_ASSERT(Value::fromReturnedValue(sparse->freeList).isEmpty());
     // ### Could explicitly free the old data
 }
 
@@ -357,12 +360,12 @@
     Value *v = d->arrayData + idx;
     if (d->attrs && d->attrs[idx].isAccessor()) {
         // double slot, free both. Order is important, so we have a double slot for allocation again afterwards.
-        v[1].setTagValue(Value::Empty_Type, Value::fromReturnedValue(d->freeList).value());
-        v[0].setTagValue(Value::Empty_Type, idx + 1);
+        v[1].setEmpty(Value::fromReturnedValue(d->freeList).emptyValue());
+        v[0].setEmpty(idx + 1);
     } else {
-        v->setTagValue(Value::Empty_Type, Value::fromReturnedValue(d->freeList).value());
+        v->setEmpty(Value::fromReturnedValue(d->freeList).emptyValue());
     }
-    d->freeList = idx;
+    d->freeList = Primitive::emptyValue(idx).asReturnedValue();
     if (d->attrs)
         d->attrs[idx].clear();
 }
@@ -400,9 +403,9 @@
             Q_ASSERT(dd->arrayData[Value::fromReturnedValue(*last).value()].value() != Value::fromReturnedValue(*last).value());
             if (dd->arrayData[Value::fromReturnedValue(*last).value()].value() == (Value::fromReturnedValue(*last).value() + 1)) {
                 // found two slots in a row
-                uint idx = Value::fromReturnedValue(*last).uint_32();
+                uint idx = Value::fromReturnedValue(*last).emptyValue();
                 Value lastV = Value::fromReturnedValue(*last);
-                lastV.setTagValue(lastV.tag(), dd->arrayData[lastV.value() + 1].value());
+                lastV.setEmpty(dd->arrayData[lastV.emptyValue() + 1].value());
                 *last = lastV.rawValue();
                 dd->attrs[idx] = Attr_Accessor;
                 return idx;
@@ -416,7 +419,8 @@
         }
         uint idx = Value::fromReturnedValue(dd->freeList).value();
         Q_ASSERT(idx != UINT_MAX);
-        dd->freeList = dd->arrayData[idx].uint_32();
+        dd->freeList = dd->arrayData[idx].asReturnedValue();
+        Q_ASSERT(Value::fromReturnedValue(dd->freeList).isEmpty());
         if (dd->attrs)
             dd->attrs[idx] = Attr_Data;
         return idx;
@@ -471,13 +475,14 @@
 
     if (isAccessor) {
         // free up both indices
-        dd->arrayData[pidx + 1].setTagValue(Value::Empty_Type, Value::fromReturnedValue(dd->freeList).value());
-        dd->arrayData[pidx].setTagValue(Value::Undefined_Type, pidx + 1);
+        dd->arrayData[pidx + 1].setEmpty(Value::fromReturnedValue(dd->freeList).emptyValue());
+        dd->arrayData[pidx].setEmpty(pidx + 1);
     } else {
-        dd->arrayData[pidx].setTagValue(Value::Empty_Type, Value::fromReturnedValue(dd->freeList).value());
+        Q_ASSERT(dd->type == Heap::ArrayData::Sparse);
+        dd->arrayData[pidx].setEmpty(Value::fromReturnedValue(dd->freeList).emptyValue());
     }
 
-    dd->freeList = pidx;
+    dd->freeList = Primitive::emptyValue(pidx).asReturnedValue();
     dd->sparse->erase(n);
     return true;
 }
diff -urN 20161021/src/qml/jsruntime/qv4persistent.cpp qtdeclarative-opensource-src-5.7.1/src/qml/jsruntime/qv4persistent.cpp
--- 20161021/src/qml/jsruntime/qv4persistent.cpp	2016-10-05 20:32:12.000000000 +0300
+++ qtdeclarative-opensource-src-5.7.1/src/qml/jsruntime/qv4persistent.cpp	2016-11-11 08:18:01.000000000 +0200
@@ -139,7 +139,7 @@
     while (p) {
         while (index < kEntriesPerPage - 1) {
             ++index;
-            if (static_cast<Page *>(p)->values[index].tag() != QV4::Value::Empty_Type)
+            if (!static_cast<Page *>(p)->values[index].isEmpty())
                 return *this;
         }
         index = -1;
diff -urN 20161021/src/qml/jsruntime/qv4value_p.h qtdeclarative-opensource-src-5.7.1/src/qml/jsruntime/qv4value_p.h
--- 20161021/src/qml/jsruntime/qv4value_p.h	2016-10-05 20:32:12.000000000 +0300
+++ qtdeclarative-opensource-src-5.7.1/src/qml/jsruntime/qv4value_p.h	2016-11-11 08:18:01.000000000 +0200
@@ -175,10 +175,7 @@
     Q_ALWAYS_INLINE quint32 value() const { return _val & quint64(~quint32(0)); }
     Q_ALWAYS_INLINE quint32 tag() const { return _val >> 32; }
 
-#if defined(V4_BOOTSTRAP)
-    Q_ALWAYS_INLINE Heap::Base *m() const { Q_UNREACHABLE(); return Q_NULLPTR; }
-    Q_ALWAYS_INLINE void setM(Heap::Base *b) { Q_UNUSED(b); Q_UNREACHABLE(); }
-#elif defined(QV4_USE_64_BIT_VALUE_ENCODING)
+#if defined(QV4_USE_64_BIT_VALUE_ENCODING)
     Q_ALWAYS_INLINE Heap::Base *m() const
     {
         Heap::Base *b;
@@ -226,6 +223,17 @@
         setTagValue(Empty_Type_Internal, quint32(i));
     }
 
+    Q_ALWAYS_INLINE void setEmpty(quint32 i)
+    {
+        setTagValue(Empty_Type_Internal, i);
+    }
+
+    Q_ALWAYS_INLINE quint32 emptyValue()
+    {
+        Q_ASSERT(isEmpty());
+        return quint32(value());
+    }
+
     enum Type {
         Undefined_Type,
         Managed_Type,
@@ -530,6 +538,7 @@
 struct Q_QML_PRIVATE_EXPORT Primitive : public Value
 {
     inline static Primitive emptyValue();
+    inline static Primitive emptyValue(uint v);
     static inline Primitive fromBoolean(bool b);
     static inline Primitive fromInt32(int i);
     inline static Primitive undefinedValue();
@@ -559,6 +568,13 @@
     return v;
 }
 
+inline Primitive Primitive::emptyValue(uint e)
+{
+    Primitive v;
+    v.setEmpty(e);
+    return v;
+}
+
 inline Primitive Primitive::nullValue()
 {
     Primitive v;
diff -urN 20161021/src/qml/memory/qv4mm.cpp qtdeclarative-opensource-src-5.7.1/src/qml/memory/qv4mm.cpp
--- 20161021/src/qml/memory/qv4mm.cpp	2016-10-05 20:32:12.000000000 +0300
+++ qtdeclarative-opensource-src-5.7.1/src/qml/memory/qv4mm.cpp	2016-11-11 08:18:01.000000000 +0200
@@ -460,7 +460,7 @@
         remainingWeakQObjectWrappers.reserve(pendingCount);
         for (int i = 0; i < pendingCount; ++i) {
             Value *v = m_pendingFreedObjectWrapperValue.at(i);
-            if (v->tag() == Value::Undefined_Type)
+            if (v->isUndefined() || v->isEmpty())
                 PersistentValueStorage::free(v);
             else
                 remainingWeakQObjectWrappers.append(v);
diff -urN 20161021/src/quick/quick.pro qtdeclarative-opensource-src-5.7.1/src/quick/quick.pro
--- 20161021/src/quick/quick.pro	2016-10-05 20:32:12.000000000 +0300
+++ qtdeclarative-opensource-src-5.7.1/src/quick/quick.pro	2016-11-11 08:18:01.000000000 +0200
@@ -13,6 +13,11 @@
     LIBS_PRIVATE += -lgcov
 }
 
+greaterThan(QT_GCC_MAJOR_VERSION, 5) {
+    # Our code is bad. Temporary workaround. Fixed in 5.8
+    QMAKE_CXXFLAGS += -fno-delete-null-pointer-checks -fno-lifetime-dse
+}
+
 QMAKE_DOCS = $$PWD/doc/qtquick.qdocconf
 
 ANDROID_LIB_DEPENDENCIES = \
diff -urN 20161021/.tag qtdeclarative-opensource-src-5.7.1/.tag
--- 20161021/.tag	2016-10-05 20:32:12.000000000 +0300
+++ qtdeclarative-opensource-src-5.7.1/.tag	2016-11-11 08:18:01.000000000 +0200
@@ -1 +1 @@
-fff4477661ae240c43088fa6d9069ccf969dbee8
+2a992040e2ef3f9dab087be3bfac05e28596672b
diff -urN 20161021/tests/auto/qml/qqmlecmascript/qqmlecmascript.pro qtdeclarative-opensource-src-5.7.1/tests/auto/qml/qqmlecmascript/qqmlecmascript.pro
--- 20161021/tests/auto/qml/qqmlecmascript/qqmlecmascript.pro	2016-10-05 20:32:12.000000000 +0300
+++ qtdeclarative-opensource-src-5.7.1/tests/auto/qml/qqmlecmascript/qqmlecmascript.pro	2016-11-11 08:18:01.000000000 +0200
@@ -13,6 +13,11 @@
 
 include (../../shared/util.pri)
 
+greaterThan(QT_GCC_MAJOR_VERSION, 5) {
+    # Our code is bad. Temporary workaround. Fixed in 5.8
+    QMAKE_CXXFLAGS += -fno-delete-null-pointer-checks -fno-lifetime-dse
+}
+
 # QMAKE_CXXFLAGS = -fprofile-arcs -ftest-coverage
 # LIBS += -lgcov