3 files changed, 17 insertions, 6 deletions
diff --git a/src/printsupport/kernel/qpaintengine_alpha.cpp b/src/printsupport/kernel/qpaintengine_alpha.cpp
index 010a628e4f..710691453a 100644
--- a/src/printsupport/kernel/qpaintengine_alpha.cpp
+++ b/src/printsupport/kernel/qpaintengine_alpha.cpp
@@ -178,7 +178,8 @@ void QAlphaPaintEngine::drawPolygon(const QPointF *points, int pointCount, Polyg
     Q_D(QAlphaPaintEngine);
 
     QPolygonF poly;
-    for (int i=0; i<pointCount; ++i)
+    poly.reserve(pointCount);
+    for (int i = 0; i < pointCount; ++i)
         poly.append(points[i]);
 
     QPainterPath path;
diff --git a/src/printsupport/kernel/qprinter.cpp b/src/printsupport/kernel/qprinter.cpp
index 44d3384d64..d404877f82 100644
--- a/src/printsupport/kernel/qprinter.cpp
+++ b/src/printsupport/kernel/qprinter.cpp
@@ -1934,7 +1934,9 @@ QList<int> QPrinter::supportedResolutions() const
     QList<QVariant> varlist
         = d->printEngine->property(QPrintEngine::PPK_SupportedResolutions).toList();
     QList<int> intlist;
-    for (int i=0; i<varlist.size(); ++i)
+    const int numSupportedResolutions = varlist.size();
+    intlist.reserve(numSupportedResolutions);
+    for (int i = 0; i < numSupportedResolutions; ++i)
         intlist << varlist.at(i).toInt();
     return intlist;
 }
diff --git a/src/printsupport/kernel/qprinterinfo.cpp b/src/printsupport/kernel/qprinterinfo.cpp
index ad488a10ed..1be574891b 100644
--- a/src/printsupport/kernel/qprinterinfo.cpp
+++ b/src/printsupport/kernel/qprinterinfo.cpp
@@ -316,7 +316,9 @@ QList<QPrinter::PaperSize> QPrinterInfo::supportedPaperSizes() const
 {
     Q_D(const QPrinterInfo);
     QList<QPrinter::PaperSize> list;
-    foreach (const QPageSize &pageSize, d->m_printDevice.supportedPageSizes())
+    const QList<QPageSize> supportedPageSizes = d->m_printDevice.supportedPageSizes();
+    list.reserve(supportedPageSizes.size());
+    foreach (const QPageSize &pageSize, supportedPageSizes)
         list.append(QPrinter::PaperSize(pageSize.id()));
     return list;
 }
@@ -336,7 +338,9 @@ QList<QPair<QString, QSizeF> > QPrinterInfo::supportedSizesWithNames() const
 {
     Q_D(const QPrinterInfo);
     QList<QPair<QString, QSizeF> > list;
-    foreach (const QPageSize &pageSize, d->m_printDevice.supportedPageSizes())
+    const QList<QPageSize> supportedPageSizes = d->m_printDevice.supportedPageSizes();
+    list.reserve(supportedPageSizes.size());
+    foreach (const QPageSize &pageSize, supportedPageSizes)
         list.append(qMakePair(pageSize.name(), pageSize.size(QPageSize::Millimeter)));
     return list;
 }
@@ -376,7 +380,9 @@ QList<QPrinter::DuplexMode> QPrinterInfo::supportedDuplexModes() const
 {
     Q_D(const QPrinterInfo);
     QList<QPrinter::DuplexMode> list;
-    foreach (QPrint::DuplexMode mode, d->m_printDevice.supportedDuplexModes())
+    const QList<QPrint::DuplexMode> supportedDuplexModes = d->m_printDevice.supportedDuplexModes();
+    list.reserve(supportedDuplexModes.size());
+    foreach (QPrint::DuplexMode mode, supportedDuplexModes)
         list << QPrinter::DuplexMode(mode);
     return list;
 }
@@ -416,7 +422,9 @@ QList<QPrinterInfo> QPrinterInfo::availablePrinters()
     QList<QPrinterInfo> list;
     QPlatformPrinterSupport *ps = QPlatformPrinterSupportPlugin::get();
     if (ps) {
-        foreach (const QString &id, ps->availablePrintDeviceIds())
+        const QStringList availablePrintDeviceIds = ps->availablePrintDeviceIds();
+        list.reserve(availablePrintDeviceIds.size());
+        foreach (const QString &id, availablePrintDeviceIds)
             list.append(QPrinterInfo(id));
     }
     return list;