diff --git a/src/opengl/qopenglframebufferobject_p.h b/src/opengl/qopenglframebufferobject_p.h
index 2eb5936cb4..62c541fdc3 100644
--- a/src/opengl/qopenglframebufferobject_p.h
+++ b/src/opengl/qopenglframebufferobject_p.h
@@ -141,7 +141,7 @@ public:
         GLenum internalFormat;
         QOpenGLSharedResourceGuard *guard;
     };
-    QList<ColorAttachment> colorAttachments;
+    QVarLengthArray<ColorAttachment, 8> colorAttachments;
 
     inline GLuint fbo() const { return fbo_guard ? fbo_guard->id() : 0; }
 };
diff --git a/src/opengl/qopenglpaintengine_p.h b/src/opengl/qopenglpaintengine_p.h
index 1a5f82b313..f2e5d97f39 100644
--- a/src/opengl/qopenglpaintengine_p.h
+++ b/src/opengl/qopenglpaintengine_p.h
@@ -332,8 +332,8 @@ public:
     QTriangulatingStroker stroker;
     QDashedStrokeProcessor dasher;
 
-    QList<GLuint> unusedVBOSToClean;
-    QList<GLuint> unusedIBOSToClean;
+    QVarLengthArray<GLuint, 8> unusedVBOSToClean;
+    QVarLengthArray<GLuint, 8> unusedIBOSToClean;
 
     const GLfloat *vertexAttribPointers[3];
 };
diff --git a/src/opengl/qplatformbackingstoreopenglsupport.cpp b/src/opengl/qplatformbackingstoreopenglsupport.cpp
index 5a9b41dd29..6f893671c0 100644
--- a/src/opengl/qplatformbackingstoreopenglsupport.cpp
+++ b/src/opengl/qplatformbackingstoreopenglsupport.cpp
@@ -94,7 +94,7 @@ static QRegion deviceRegion(const QRegion &region, QWindow *window, const QPoint
     if (offset.isNull() && window->devicePixelRatio() <= 1)
         return region;
 
-    QList<QRect> rects;
+    QVarLengthArray<QRect, 4> rects;
     rects.reserve(region.rectCount());
     for (const QRect &rect : region)
         rects.append(deviceRect(rect.translated(offset), window));