Patch CUB with http://github.com/NVlabs/cub/pull/170 to build with clang.

PiperOrigin-RevId: 270958366

tensorflow/workspace.bzl

@@ -722,6 +722,7 @@ def tf_repositories(path_prefix = "", tf_repo_name = ""):
     tf_http_archive(
         name = "cub_archive",
         build_file = clean_dep("//third_party:cub.BUILD"),
+        patch_file = clean_dep("//third_party:cub.pr170.patch"),
         sha256 = "6bfa06ab52a650ae7ee6963143a0bbc667d6504822cbd9670369b598f18c58c3",
         strip_prefix = "cub-1.8.0",
         urls = [

third_party/cub.pr170.patch

@@ -0,0 +1,48 @@
+From fd6e7a61a16a17fa155cbd717de0c79001af71e6 Mon Sep 17 00:00:00 2001
+From: Artem Belevich <tra@google.com>
+Date: Mon, 23 Sep 2019 11:18:56 -0700
+Subject: [PATCH] Fix CUDA version detection in CUB
+
+This fixes the problem with CUB using deprecated shfl/vote instructions when CUB
+is compiled with clang (e.g. some TensorFlow builds).
+---
+ cub/util_arch.cuh | 3 ++-
+ cub/util_type.cuh | 4 ++--
+ 2 files changed, 4 insertions(+), 3 deletions(-)
+
+diff --git a/cub/util_arch.cuh b/cub/util_arch.cuh
+index 87c5ea2fb..9ad9d1cbb 100644
+--- a/cub/util_arch.cuh
++++ b/cub/util_arch.cuh
+@@ -44,7 +44,8 @@ namespace cub {
+ 
+ #ifndef DOXYGEN_SHOULD_SKIP_THIS    // Do not document
+ 
+-#if (__CUDACC_VER_MAJOR__ >= 9) && !defined(CUB_USE_COOPERATIVE_GROUPS)
++#if !defined(CUB_USE_COOPERATIVE_GROUPS) && \
++    (__CUDACC_VER_MAJOR__ >= 9 || CUDA_VERSION >= 9000)
+     #define CUB_USE_COOPERATIVE_GROUPS
+ #endif
+ 
+diff --git a/cub/util_type.cuh b/cub/util_type.cuh
+index 0ba41e1ed..b2433d735 100644
+--- a/cub/util_type.cuh
++++ b/cub/util_type.cuh
+@@ -37,7 +37,7 @@
+ #include <limits>
+ #include <cfloat>
+ 
+-#if (__CUDACC_VER_MAJOR__ >= 9)
++#if (__CUDACC_VER_MAJOR__ >= 9 || CUDA_VERSION >= 9000)
+     #include <cuda_fp16.h>
+ #endif
+ 
+@@ -1063,7 +1063,7 @@ struct FpLimits<double>
+ };
+ 
+ 
+-#if (__CUDACC_VER_MAJOR__ >= 9)
++#if (__CUDACC_VER_MAJOR__ >= 9 || CUDA_VERSION >= 9000)
+ template <>
+ struct FpLimits<__half>
+ {