From 8396ad04c4b1d3b5fc9d337a3cc03bcfddc2155d Mon Sep 17 00:00:00 2001
From: Kenichi Maehashi <webmaster@kenichimaehashi.com>
Date: Thu, 5 Apr 2018 19:28:48 +0900
Subject: [PATCH 1/2] add test for 32-bit boundary for cupy.concatenate

---
 tests/cupy_tests/manipulation_tests/test_join.py | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/tests/cupy_tests/manipulation_tests/test_join.py b/tests/cupy_tests/manipulation_tests/test_join.py
index a4c6dacfaeb..e03a121d595 100644
--- a/tests/cupy_tests/manipulation_tests/test_join.py
+++ b/tests/cupy_tests/manipulation_tests/test_join.py
@@ -108,6 +108,13 @@ def test_concatenate_many_multi_dptye(self, xp):
         b = testing.shaped_arange((2, 1), xp, 'f')
         return xp.concatenate((a, b) * 1024, axis=1)
 
+    @testing.numpy_cupy_array_equal()
+    @testing.slow
+    def test_concatenate_32bit_boundary(self, xp):
+        a = xp.zeros((2 ** 30,), dtype=xp.int8)
+        b = xp.zeros((2 ** 30,), dtype=xp.int8)
+        return xp.concatenate([a, b])
+
     def test_concatenate_wrong_ndim(self):
         a = cupy.empty((2, 3))
         b = cupy.empty((2,))

From b3b9835e5cb1a40b61ba7f60de3c51de344356bd Mon Sep 17 00:00:00 2001
From: Kenichi Maehashi <webmaster@kenichimaehashi.com>
Date: Thu, 5 Apr 2018 16:54:16 +0900
Subject: [PATCH 2/2] fix to avoid overflow

---
 cupy/core/core.pyx     | 2 +-
 cupy/core/internal.pyx | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/cupy/core/core.pyx b/cupy/core/core.pyx
index e71e5e05636..a922754c307 100644
--- a/cupy/core/core.pyx
+++ b/cupy/core/core.pyx
@@ -2467,7 +2467,7 @@ cpdef ndarray concatenate_method(tup, int axis):
 
 cpdef ndarray _concatenate(list arrays, Py_ssize_t axis, tuple shape, dtype):
     cdef ndarray a, ret
-    cdef int i
+    cdef Py_ssize_t i
     cdef bint all_same_type, same_shape_and_contiguous
     cdef Py_ssize_t axis_size
     # If arrays are large, Issuing each copy method is efficient.
diff --git a/cupy/core/internal.pyx b/cupy/core/internal.pyx
index f3815f46a76..91b48d6e8ef 100644
--- a/cupy/core/internal.pyx
+++ b/cupy/core/internal.pyx
@@ -143,7 +143,7 @@ cpdef vector.vector[Py_ssize_t] infer_unknown_dimension(
 
 
 @cython.profile(False)
-cpdef inline int _extract_slice_element(x) except *:
+cpdef inline Py_ssize_t _extract_slice_element(x) except *:
     try:
         return x.__index__()
     except AttributeError: