Deal with unused functions, as found by the Intel compiler

Use Q_DECL_UNUSED for the one that is possibly unused (we have two overloads so that one gets selected):
qglobal.cpp(2069): warning #177: function "<unnamed>::fromstrerror_helper(int, const QByteArray &)" was declared but never referenced

Remove functions really not used:
qbezier.cpp(153): warning #177: function "findInflections" was declared but never referenced
qbezier.cpp(534): warning #177: function "splitBezierAt" was declared but never referenced
qpathclipper.cpp(1039): warning #177: function "midPoint" was declared but never referenced
qpainter.cpp(119): warning #177: function "check_gradient" was declared but never referenced
qdockarealayout.cpp(2580): warning #177: function "qMin(int, int, int)" was declared but never referenced
qmainwindowlayout.cpp(1019): warning #177: function "validateDockWidgetArea" was declared but never referenced
qgraphicsanchorlayout_p.cpp(670): warning #177: function "checkAdd" was declared but never referenced
qcups.cpp(481): warning #177: function "paperSize2String" was declared but never referenced
complexwidgets.cpp(373): warning #177: function "removeInvisibleWidgetsFromList" was declared but never referenced

Change-Id: I1e5558e206b04edea381442030dc69536198d966
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@digia.com>
Reviewed-by: Robin Burchell <robin+qt@viroteck.net>

src/corelib/global/qglobal.cpp

@@ -2066,11 +2066,11 @@ namespace {
     // version in portable code. However, it's impossible to do that if
     // _GNU_SOURCE is defined so we use C++ overloading to decide what to do
     // depending on the return type
-    static inline QString fromstrerror_helper(int, const QByteArray &buf)
+    static inline Q_DECL_UNUSED QString fromstrerror_helper(int, const QByteArray &buf)
     {
         return QString::fromLocal8Bit(buf);
     }
-    static inline QString fromstrerror_helper(const char *str, const QByteArray &)
+    static inline Q_DECL_UNUSED QString fromstrerror_helper(const char *str, const QByteArray &)
     {
         return QString::fromLocal8Bit(str);
     }

src/gui/painting/qbezier.cpp

@@ -150,33 +150,6 @@ static inline int quadraticRoots(qreal a, qreal b, qreal c,
     }
 }
 
-static inline bool findInflections(qreal a, qreal b, qreal c,
-                                   qreal *t1 , qreal *t2, qreal *tCups)
-{
-    qreal r1 = 0, r2 = 0;
-
-    short rootsCount = quadraticRoots(a, b, c, &r1, &r2);
-
-    if (rootsCount >= 1) {
-        if (r1 < r2) {
-            *t1 = r1;
-            *t2 = r2;
-        } else {
-            *t1 = r2;
-            *t2 = r1;
-        }
-        if (!qFuzzyIsNull(a))
-            *tCups = qreal(0.5) * (-b / a);
-        else
-            *tCups = 2;
-
-        return true;
-    }
-
-    return false;
-}
-
-
 void QBezier::addToPolygon(QPolygonF *polygon, qreal bezier_flattening_threshold) const
 {
     QBezier beziers[10];
@@ -531,34 +504,6 @@ static QDebug operator<<(QDebug dbg, const QBezier &bz)
 }
 #endif
 
-static inline void splitBezierAt(const QBezier &bez, qreal t,
-                                 QBezier *left, QBezier *right)
-{
-    left->x1 = bez.x1;
-    left->y1 = bez.y1;
-
-    left->x2 = bez.x1 + t * ( bez.x2 - bez.x1 );
-    left->y2 = bez.y1 + t * ( bez.y2 - bez.y1 );
-
-    left->x3 = bez.x2 + t * ( bez.x3 - bez.x2 ); // temporary holding spot
-    left->y3 = bez.y2 + t * ( bez.y3 - bez.y2 ); // temporary holding spot
-
-    right->x3 = bez.x3 + t * ( bez.x4 - bez.x3 );
-    right->y3 = bez.y3 + t * ( bez.y4 - bez.y3 );
-
-    right->x2 = left->x3 + t * ( right->x3 - left->x3);
-    right->y2 = left->y3 + t * ( right->y3 - left->y3);
-
-    left->x3 = left->x2 + t * ( left->x3 - left->x2 );
-    left->y3 = left->y2 + t * ( left->y3 - left->y2 );
-
-    left->x4 = right->x1 = left->x3 + t * (right->x2 - left->x3);
-    left->y4 = right->y1 = left->y3 + t * (right->y2 - left->y3);
-
-    right->x4 = bez.x4;
-    right->y4 = bez.y4;
-}
-
 qreal QBezier::length(qreal error) const
 {
     qreal length = qreal(0.0);

src/gui/painting/qpathclipper.cpp

@@ -1036,16 +1036,6 @@ qreal QWingedEdge::delta(int vertex, int a, int b) const
         return result;
 }
 
-static inline QPointF midPoint(const QWingedEdge &list, int ei)
-{
-    const QPathEdge *ep = list.edge(ei);
-    Q_ASSERT(ep);
-
-    const QPointF a = *list.vertex(ep->first);
-    const QPointF b = *list.vertex(ep->second);
-    return a + 0.5 * (b - a);
-}
-
 QWingedEdge::TraversalStatus QWingedEdge::findInsertStatus(int vi, int ei) const
 {
     const QPathVertex *vp = vertex(vi);

src/plugins/accessible/widgets/complexwidgets.cpp

@@ -370,18 +370,6 @@ QStringList QAccessibleComboBox::keyBindingsForAction(const QString &/*actionNam
 
 #endif // QT_NO_COMBOBOX
 
-static inline void removeInvisibleWidgetsFromList(QWidgetList *list)
-{
-    if (!list || list->isEmpty())
-        return;
-
-    for (int i = 0; i < list->count(); ++i) {
-        QWidget *widget = list->at(i);
-        if (!widget->isVisible())
-            list->removeAt(i);
-    }
-}
-
 #ifndef QT_NO_SCROLLAREA
 // ======================= QAccessibleAbstractScrollArea =======================
 QAccessibleAbstractScrollArea::QAccessibleAbstractScrollArea(QWidget *widget)

src/printsupport/kernel/qcups.cpp

@@ -478,15 +478,6 @@ static inline QPrinter::PaperSize string2PaperSize(const char *name)
     return QPrinter::Custom;
 }
 
-static inline const char *paperSize2String(QPrinter::PaperSize size)
-{
-    for (int i = 0; i < QPrinter::NPageSize; ++i) {
-        if (size == named_sizes_map[i].size)
-            return named_sizes_map[i].name;
-    }
-    return 0;
-}
-
 QList<QPrinter::PaperSize> QCUPSSupport::getCupsPrinterPaperSizes(int cupsPrinterIndex)
 {
     QList<QPrinter::PaperSize> result;

src/widgets/graphicsview/qgraphicsanchorlayout_p.cpp

@@ -660,20 +660,6 @@ Qt::AnchorPoint QGraphicsAnchorLayoutPrivate::oppositeEdge(Qt::AnchorPoint edge)
 }
 
 
-/*!
- * \internal
- *
- * helper function in order to avoid overflowing anchor sizes
- * the returned size will never be larger than FLT_MAX
- *
- */
-inline static qreal checkAdd(qreal a, qreal b)
-{
-    if (FLT_MAX - b  < a)
-        return FLT_MAX;
-    return a + b;
-}
-
 /*!
     \internal
 

src/widgets/widgets/qdockarealayout.cpp

@@ -2577,7 +2577,6 @@ void QDockAreaLayout::remove(const QList<int> &path)
     docks[index].remove(path.mid(1));
 }
 
-static inline int qMin(int i1, int i2, int i3) { return qMin(i1, qMin(i2, i3)); }
 static inline int qMax(int i1, int i2, int i3) { return qMax(i1, qMax(i2, i3)); }
 
 void QDockAreaLayout::getGrid(QVector<QLayoutStruct> *_ver_struct_list,

src/widgets/widgets/qmainwindowlayout.cpp

@@ -1016,19 +1016,6 @@ void QMainWindowLayout::toggleToolBarsVisible()
 
 #ifndef QT_NO_DOCKWIDGET
 
-static inline void validateDockWidgetArea(Qt::DockWidgetArea &area)
-{
-    switch (area) {
-    case Qt::LeftDockWidgetArea:
-    case Qt::RightDockWidgetArea:
-    case Qt::TopDockWidgetArea:
-    case Qt::BottomDockWidgetArea:
-        break;
-    default:
-        area = Qt::LeftDockWidgetArea;
-    }
-}
-
 static QInternal::DockPosition toDockPos(Qt::DockWidgetArea area)
 {
     switch (area) {