diff --git a/Eigen/QtAlignedMalloc b/Eigen/QtAlignedMalloc
index fde227328..dba7cb29e 100644
--- a/Eigen/QtAlignedMalloc
+++ b/Eigen/QtAlignedMalloc
@@ -3,6 +3,7 @@
 #define EIGEN_QTMALLOC_MODULE_H
 
 #include "Core"
+#include <QtCore/QVectorData>
 
 #if (!EIGEN_MALLOC_ALREADY_ALIGNED)
 
@@ -24,6 +25,16 @@ inline void *qRealloc(void *ptr, size_t size)
   return newPtr;
 }
 
+// needed to copy that too because it is implemented in the qt binary library, hence
+// wouldn't otherwise honor our qMalloc.
+QVectorData *QVectorData::malloc(int sizeofTypedData, int size, int sizeofT, QVectorData *init)
+{
+    QVectorData* p = (QVectorData *)qMalloc(sizeofTypedData + (size - 1) * sizeofT);
+    Q_CHECK_PTR(p);
+    ::memcpy(p, init, sizeofTypedData + (qMin(size, init->alloc) - 1) * sizeofT);
+    return p;
+}
+
 #endif
 
 #endif // EIGEN_QTMALLOC_MODULE_H