From 184274c89300c36f1df55fb8c7c0e469a184789b Mon Sep 17 00:00:00 2001
From: Olivier Parcollet <olivier.parcollet@cea.fr>
Date: Mon, 18 Nov 2013 22:48:52 +0100
Subject: [PATCH] gf : fix bug in mesh_pt_generator

- in the default constructor, do not call the pointer
that may be null.
- appeared only in python (unused in c++), for new matsubara...
---
 triqs/gfs/meshes/discrete.hpp   | 1 +
 triqs/gfs/meshes/linear.hpp     | 1 +
 triqs/gfs/meshes/mesh_tools.hpp | 3 ++-
 triqs/gfs/meshes/product.hpp    | 1 +
 4 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/triqs/gfs/meshes/discrete.hpp b/triqs/gfs/meshes/discrete.hpp
index be4c95db..ef00f653 100644
--- a/triqs/gfs/meshes/discrete.hpp
+++ b/triqs/gfs/meshes/discrete.hpp
@@ -46,6 +46,7 @@ namespace triqs { namespace gfs {
     discrete_mesh const * m;  
     index_t _index;
     public:
+    mesh_point_t() = default;
     mesh_point_t( discrete_mesh const & mesh, index_t const & index_): m(&mesh), _index(index_) {}
     void advance() { ++_index;}
     typedef size_t cast_t;
diff --git a/triqs/gfs/meshes/linear.hpp b/triqs/gfs/meshes/linear.hpp
index c632d4da..2128ede0 100644
--- a/triqs/gfs/meshes/linear.hpp
+++ b/triqs/gfs/meshes/linear.hpp
@@ -87,6 +87,7 @@ namespace gfs {
    index_t _index;
 
    public:
+   mesh_point_t() : m(nullptr) {}
    mesh_point_t(linear_mesh const &mesh, index_t const &index_) : m(&mesh), _index(index_) {}
    void advance() { ++_index; }
    typedef domain_pt_t cast_t;
diff --git a/triqs/gfs/meshes/mesh_tools.hpp b/triqs/gfs/meshes/mesh_tools.hpp
index fae3dc75..7f0fe6f7 100644
--- a/triqs/gfs/meshes/mesh_tools.hpp
+++ b/triqs/gfs/meshes/mesh_tools.hpp
@@ -63,7 +63,8 @@ namespace gfs {
     // do NOT check = of mesh, otherwise e.g. block iterator does not work (infinite loop...)
     //bool equal(mesh_pt_generator const & other) const { return ((mesh == other.mesh) && (other.u==u) );}
     public:
-    mesh_pt_generator( MeshType const * m=NULL, bool atEnd = false): mesh(m), u(atEnd ? m->size(): 0), pt((*m)[typename MeshType::index_t()]) {}
+    mesh_pt_generator(): mesh(nullptr), u(0) {}
+    mesh_pt_generator( MeshType const * m, bool atEnd = false): mesh(m), u(atEnd ? m->size(): 0), pt((*m)[typename MeshType::index_t()]) {}
     void increment() { ++u; pt.advance(); }
     bool at_end() const { return (u>=mesh->size());}
     typename MeshType::domain_t::point_t to_point() const { return pt;}    
diff --git a/triqs/gfs/meshes/product.hpp b/triqs/gfs/meshes/product.hpp
index c1703abe..12b4107e 100644
--- a/triqs/gfs/meshes/product.hpp
+++ b/triqs/gfs/meshes/product.hpp
@@ -83,6 +83,7 @@ namespace triqs { namespace gfs {
     struct F2 { template<typename M> typename M::mesh_point_t operator()(M const & m, typename M::index_t const & i) const { return m[i];}};
     struct F1 { template<typename M> typename M::mesh_point_t operator()(M const & m) const { return m[typename M::index_t()];}};
     public :
+    mesh_point_t() = default;
     mesh_point_t(mesh_product const & m_, index_t index_ ) : m(&m_), _c (triqs::tuple::apply_on_zip(F2(), m_.m_tuple, index_)), _atend(false) {}
     mesh_point_t(mesh_product const & m_)                  : m(&m_), _c (triqs::tuple::apply(F1(), m_.m_tuple)), _atend(false)    {}
     m_pt_tuple_t const & components_tuple() const { return _c;}