diff --git a/Eigen/src/QR/QR.h b/Eigen/src/QR/QR.h
index b8161733a..66e263e33 100644
--- a/Eigen/src/QR/QR.h
+++ b/Eigen/src/QR/QR.h
@@ -270,12 +270,15 @@ bool QR<MatrixType>::solve(
   ei_assert(m_isInitialized && "QR is not initialized.");
   const int rows = m_qr.rows();
   ei_assert(b.rows() == rows);
+  // enforce the computation of the rank
+  rank();
+  
   result->resize(m_qr.cols(), b.cols());
   
   // TODO(keir): There is almost certainly a faster way to multiply by
   // Q^T without explicitly forming matrixQ(). Investigate.
   *result = matrixQ().transpose()*b;
-  
+
   if(m_rank==0)
     return result->isZero();