12 files changed, 26 insertions, 4 deletions

diff --git a/src/plugins/imageformats/gif/qgifhandler.cpp b/src/plugins/imageformats/gif/qgifhandler.cpp
index de985d8..0f6a349 100644
--- a/src/plugins/imageformats/gif/qgifhandler.cpp
+++ b/src/plugins/imageformats/gif/qgifhandler.cpp
@@ -234,7 +234,7 @@ int QGIFFormat::decode(QImage *image, const uchar *buffer, int length,
 
 #define LM(l, m) (((m)<<8)|l)
     digress = false;
-    int initial = length;
+    const int initial = length;
     while (!digress && length) {
         length--;
         unsigned char ch=*buffer++;
@@ -333,7 +333,7 @@ int QGIFFormat::decode(QImage *image, const uchar *buffer, int length,
                     sheight = newtop + newheight;
 
                 QImage::Format format = trans_index >= 0 ? QImage::Format_ARGB32 : QImage::Format_RGB32;
-                if (image->isNull() || (image->size() != QSize(swidth, sheight)) || image->format() != format) {
+                if (image->isNull()) {
                     (*image) = QImage(swidth, sheight, format);
                     memset(image->bits(), 0, image->numBytes());
 
diff --git a/tests/auto/qimagereader/images/qt.gif b/tests/auto/qimagereader/images/qt.gif
new file mode 100644
index 0000000..e0a5a80
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt.gif
diff --git a/tests/auto/qimagereader/images/qt1.gif b/tests/auto/qimagereader/images/qt1.gif
new file mode 100644
index 0000000..0ce910c
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt1.gif
diff --git a/tests/auto/qimagereader/images/qt2.gif b/tests/auto/qimagereader/images/qt2.gif
new file mode 100644
index 0000000..993a315
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt2.gif
diff --git a/tests/auto/qimagereader/images/qt3.gif b/tests/auto/qimagereader/images/qt3.gif
new file mode 100644
index 0000000..7391678
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt3.gif
diff --git a/tests/auto/qimagereader/images/qt4.gif b/tests/auto/qimagereader/images/qt4.gif
new file mode 100644
index 0000000..41109a9
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt4.gif
diff --git a/tests/auto/qimagereader/images/qt5.gif b/tests/auto/qimagereader/images/qt5.gif
new file mode 100644
index 0000000..5a3fb54
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt5.gif
diff --git a/tests/auto/qimagereader/images/qt6.gif b/tests/auto/qimagereader/images/qt6.gif
new file mode 100644
index 0000000..f22e7c9
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt6.gif
diff --git a/tests/auto/qimagereader/images/qt7.gif b/tests/auto/qimagereader/images/qt7.gif
new file mode 100644
index 0000000..a315671
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt7.gif
diff --git a/tests/auto/qimagereader/images/qt8.gif b/tests/auto/qimagereader/images/qt8.gif
new file mode 100644
index 0000000..2a7d09e
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt8.gif
diff --git a/tests/auto/qimagereader/qimagereader.qrc b/tests/auto/qimagereader/qimagereader.qrc
index 13ce582..e3113c6 100644
--- a/tests/auto/qimagereader/qimagereader.qrc
+++ b/tests/auto/qimagereader/qimagereader.qrc
@@ -1,5 +1,5 @@
-<!DOCTYPE RCC><RCC version="1.0">
-    <qresource>
+<RCC>
+    <qresource prefix="/" >
         <file>images/16bpp.bmp</file>
         <file>images/4bpp-rle.bmp</file>
         <file>images/YCbCr_cmyk.jpg</file>
@@ -47,5 +47,14 @@
         <file>images/tst7.png</file>
         <file>images/transparent.xpm</file>
         <file>images/trolltech.gif</file>
+        <file>images/qt.gif</file>
+        <file>images/qt1.gif</file>
+        <file>images/qt2.gif</file>
+        <file>images/qt3.gif</file>
+        <file>images/qt4.gif</file>
+        <file>images/qt5.gif</file>
+        <file>images/qt6.gif</file>
+        <file>images/qt7.gif</file>
+        <file>images/qt8.gif</file>
     </qresource>
 </RCC>
diff --git a/tests/auto/qimagereader/tst_qimagereader.cpp b/tests/auto/qimagereader/tst_qimagereader.cpp
index 18900b4..1403280 100644
--- a/tests/auto/qimagereader/tst_qimagereader.cpp
+++ b/tests/auto/qimagereader/tst_qimagereader.cpp
@@ -136,6 +136,7 @@ private slots:
 
 #if defined QTEST_HAVE_GIF
     void gifHandlerBugs();
+    void animatedGif();
 #endif
 
     void readCorruptImage_data();
@@ -671,6 +672,18 @@ void tst_QImageReader::gifHandlerBugs()
         QCOMPARE(im1.convertToFormat(QImage::Format_ARGB32), im2.convertToFormat(QImage::Format_ARGB32));
     }
 }
+
+void tst_QImageReader::animatedGif()
+{
+    QImageReader io(prefix + "qt.gif");
+    QImage image= io.read();
+    int i=0;
+    while(!image.isNull()){
+        QString frameName = QString(prefix + "qt%1.gif").arg(++i);
+        QCOMPARE(image, QImage(frameName));
+        image=io.read();
+    }
+}
 #endif
 
 class Server : public QObject