From 0b308e79c4731c093a8bbe2adc3bb9dc4ff3eb12 Mon Sep 17 00:00:00 2001
From: Jitse Niesen <jitse@maths.leeds.ac.uk>
Date: Fri, 24 Jun 2011 13:47:11 +0100
Subject: [PATCH] Add DenseStorage specializations for dynamic size with
 MaxSize = 0 (bug #288). This is necessary for instantiations like
 Matrix<float,Dynamic,Dynamic,0,0,0>.

---
 Eigen/src/Core/DenseStorage.h | 10 ++++++++++
 test/zerosized.cpp            |  5 +++++
 2 files changed, 15 insertions(+)

diff --git a/Eigen/src/Core/DenseStorage.h b/Eigen/src/Core/DenseStorage.h
index 813053b00..2464aaab8 100644
--- a/Eigen/src/Core/DenseStorage.h
+++ b/Eigen/src/Core/DenseStorage.h
@@ -128,6 +128,16 @@ template<typename T, int _Rows, int _Cols, int _Options> class DenseStorage<T, 0
     inline T *data() { return 0; }
 };
 
+// more specializations for null matrices; these are necessary to resolve ambiguities
+template<typename T, int _Options> class DenseStorage<T, 0, Dynamic, Dynamic, _Options>
+: public DenseStorage<T, 0, 0, 0, _Options> { };
+
+template<typename T, int _Rows, int _Options> class DenseStorage<T, 0, _Rows, Dynamic, _Options>
+: public DenseStorage<T, 0, 0, 0, _Options> { };
+
+template<typename T, int _Cols, int _Options> class DenseStorage<T, 0, Dynamic, _Cols, _Options>
+: public DenseStorage<T, 0, 0, 0, _Options> { };
+
 // dynamic-size matrix with fixed-size storage
 template<typename T, int Size, int _Options> class DenseStorage<T, Size, Dynamic, Dynamic, _Options>
 {
diff --git a/test/zerosized.cpp b/test/zerosized.cpp
index 06e31cc09..c5d2cc6ed 100644
--- a/test/zerosized.cpp
+++ b/test/zerosized.cpp
@@ -62,8 +62,13 @@ void test_zerosized()
   zeroSizedMatrix<Matrix3i>();
   zeroSizedMatrix<Matrix<float, 2, Dynamic> >();
   zeroSizedMatrix<MatrixXf>();
+  zeroSizedMatrix<Matrix<float, 0, 0> >();
+  zeroSizedMatrix<Matrix<float, Dynamic, 0, 0, 0, 0> >();
+  zeroSizedMatrix<Matrix<float, 0, Dynamic, 0, 0, 0> >();
+  zeroSizedMatrix<Matrix<float, Dynamic, Dynamic, 0, 0, 0> >();
   
   zeroSizedVector<Vector2d>();
   zeroSizedVector<Vector3i>();
   zeroSizedVector<VectorXf>();
+  zeroSizedVector<Matrix<float, 0, 1> >();
 }