From 30cbbc7b0ff3566908413930b641ae9278c9a841 Mon Sep 17 00:00:00 2001
From: Filipe Maia <filipe.c.maia@gmail.com>
Date: Wed, 8 Jul 2015 18:17:37 +0200
Subject: [PATCH 1/3] Fix double free issue.

---
 include/af/index.h    | 20 ++++++++++++++++++++
 src/api/cpp/index.cpp | 14 ++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/include/af/index.h b/include/af/index.h
index 295739077e..7d0763b928 100644
--- a/include/af/index.h
+++ b/include/af/index.h
@@ -103,6 +103,15 @@ class AFAPI index {
     ///
     index(const af::array& idx0);
 
+    ///
+    /// \brief Copy constructor
+    ///
+    /// \param[in] idx0 is index to copy.
+    ///
+    /// \sa indexing
+    ///
+    index(const index& idx0);
+
     ///
     /// \brief Returns true if the \ref af::index represents a af::span object
     ///
@@ -116,6 +125,17 @@ class AFAPI index {
     /// \returns the af_index_t represented by this object
     ///
     const af_index_t& get() const;
+
+    ///
+    /// \brief Assigns idx0 to this index
+    ///
+    /// \param[in] idx0 is the index to be assigned to the /ref af::index
+    /// \returns the reference to this
+    /// 
+    ///
+    index & operator=(const index& idx0);
+
+
 };
 
 ///
diff --git a/src/api/cpp/index.cpp b/src/api/cpp/index.cpp
index 2b66dd62c1..afaa716821 100644
--- a/src/api/cpp/index.cpp
+++ b/src/api/cpp/index.cpp
@@ -75,11 +75,25 @@ index::index(const af::array& idx0) {
     impl.isBatch = false;
 }
 
+index::index(const af::index& idx0) {  
+    *this = idx0;
+}
+
 index::~index() {
     if (!impl.isSeq)
         af_release_array(impl.idx.arr);
 }
 
+index & index::operator=(const index& idx0) {
+    impl = idx0.get();
+    if(impl.isSeq == false){
+        // increment reference count to avoid double free
+        // when/if idx0 is destroyed
+        AF_THROW(af_retain_array(&impl.idx.arr, impl.idx.arr));
+    }
+    return *this;
+}
+
 
 static bool operator==(const af_seq& lhs, const af_seq& rhs) {
     return lhs.begin == rhs.begin && lhs.end == rhs.end && lhs.step == rhs.step;

From 9cbc641934566f3cee24e5c4d4e4f5b2d42c34a6 Mon Sep 17 00:00:00 2001
From: Filipe Maia <filipe.c.maia@gmail.com>
Date: Wed, 8 Jul 2015 21:34:47 +0200
Subject: [PATCH 2/3] Add test for index copy assignment.

---
 test/index.cpp | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/test/index.cpp b/test/index.cpp
index 9f23ae5fe3..28b57459fc 100644
--- a/test/index.cpp
+++ b/test/index.cpp
@@ -1251,3 +1251,13 @@ TEST(Indexing, SNIPPET_indexing_ref)
     //! [ex_indexing_ref]
     //TODO: Confirm the outputs are correct. see #697
 }
+
+TEST(Indexing, SNIPPET_indexing_copy)
+{
+  af::array A = af::constant(0,1, s32);
+  af::index s1;
+  s1 = af::index(A);
+  // At exit both A and s1 will be destroyed
+  // but the underlying array should only be
+  // freed once.
+}

From 4d23d4136dad5063f53d7df09a0086e8f492f9eb Mon Sep 17 00:00:00 2001
From: Filipe Maia <filipe.c.maia@gmail.com>
Date: Thu, 9 Jul 2015 00:27:02 +0200
Subject: [PATCH 3/3] Add move constructor and move assignment op

---
 include/af/index.h    | 16 +++++++++++++++-
 src/api/cpp/index.cpp | 11 +++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/include/af/index.h b/include/af/index.h
index 7d0763b928..373804dc17 100644
--- a/include/af/index.h
+++ b/include/af/index.h
@@ -135,7 +135,21 @@ class AFAPI index {
     ///
     index & operator=(const index& idx0);
 
-
+#if __cplusplus > 199711L
+    ///
+    /// \brief Move constructor
+    ///
+    /// \param[in] idx0 is index to copy.
+    ///
+    index(index &&idx0);
+    ///
+    /// \brief Move assignment operator
+    ///
+    /// \param[in] idx0 is the index to be assigned to the /ref af::index
+    /// \returns a reference to this
+    ///
+    index& operator=(index &&idx0);
+#endif
 };
 
 ///
diff --git a/src/api/cpp/index.cpp b/src/api/cpp/index.cpp
index afaa716821..ccc698bc3c 100644
--- a/src/api/cpp/index.cpp
+++ b/src/api/cpp/index.cpp
@@ -94,6 +94,17 @@ index & index::operator=(const index& idx0) {
     return *this;
 }
 
+#if __cplusplus > 199711L
+index::index(index &&idx0) {
+    impl = idx0.impl;
+}
+
+index& index::operator=(index &&idx0) {
+    impl = idx0.impl;
+    return *this;
+}
+#endif
+
 
 static bool operator==(const af_seq& lhs, const af_seq& rhs) {
     return lhs.begin == rhs.begin && lhs.end == rhs.end && lhs.step == rhs.step;