diff --git a/common/comic.cpp b/common/comic.cpp
index 50a31d2c..b6ea1792 100644
--- a/common/comic.cpp
+++ b/common/comic.cpp
@@ -27,7 +27,7 @@ QStringList Comic::getSupportedImageFormats()
 {
     QList<QByteArray> supportedImageFormats = QImageReader::supportedImageFormats();
     QStringList supportedImageFormatStrings;
-    for (QByteArray item : supportedImageFormats) {
+    for (QByteArray &item : supportedImageFormats) {
         supportedImageFormatStrings.append(QString::fromLocal8Bit("*." + item));
     }
     return supportedImageFormatStrings;
@@ -37,7 +37,7 @@ QStringList Comic::getSupportedImageLiteralFormats()
 {
     QList<QByteArray> supportedImageFormats = QImageReader::supportedImageFormats();
     QStringList supportedImageFormatStrings;
-    for (QByteArray item : supportedImageFormats) {
+    for (QByteArray &item : supportedImageFormats) {
         supportedImageFormatStrings.append(QString::fromLocal8Bit(item));
     }
     return supportedImageFormatStrings;
diff --git a/common/gl/yacreader_flow_gl.cpp b/common/gl/yacreader_flow_gl.cpp
index ba61a2b7..07d19062 100644
--- a/common/gl/yacreader_flow_gl.cpp
+++ b/common/gl/yacreader_flow_gl.cpp
@@ -1276,7 +1276,7 @@ YACReaderPageFlowGL::~YACReaderPageFlowGL()
 
     makeCurrent();
 
-    for (auto image : images) {
+    for (auto &image : images) {
         if (image.texture != defaultTexture) {
             if (image.texture->isCreated()) {
                 image.texture->destroy();