From 044efea965b484fcf13551c8edabdb62c4b4b462 Mon Sep 17 00:00:00 2001
From: Benoit Steiner <benoit.steiner.goog@gmail.com>
Date: Wed, 23 Mar 2016 20:02:11 -0700
Subject: [PATCH] Made sure that the cxx11_tensor_cuda test can be compiled
 even without support for cxx11.

---
 unsupported/test/cxx11_tensor_cuda.cu | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/unsupported/test/cxx11_tensor_cuda.cu b/unsupported/test/cxx11_tensor_cuda.cu
index 1964d9e07f..4d8465756e 100644
--- a/unsupported/test/cxx11_tensor_cuda.cu
+++ b/unsupported/test/cxx11_tensor_cuda.cu
@@ -853,6 +853,10 @@ void test_cxx11_tensor_cuda()
   CALL_SUBTEST_3(test_cuda_convolution_3d<ColMajor>());
   CALL_SUBTEST_3(test_cuda_convolution_3d<RowMajor>());
 
+#if __cplusplus > 199711L
+  // std::erf, std::erfc, and so on where only added in c++11. We use them
+  // as a golden reference to validate the results produced by Eigen. Therefore
+  // we can only run these tests if we use a c++11 compiler.
   CALL_SUBTEST_4(test_cuda_lgamma<float>(1.0f));
   CALL_SUBTEST_4(test_cuda_lgamma<float>(100.0f));
   CALL_SUBTEST_4(test_cuda_lgamma<float>(0.01f));
@@ -860,6 +864,7 @@ void test_cxx11_tensor_cuda()
 
   CALL_SUBTEST_4(test_cuda_digamma<float>());
 
+
   CALL_SUBTEST_4(test_cuda_erf<float>(1.0f));
   CALL_SUBTEST_4(test_cuda_erf<float>(100.0f));
   CALL_SUBTEST_4(test_cuda_erf<float>(0.01f));
@@ -894,4 +899,5 @@ void test_cxx11_tensor_cuda()
 
   CALL_SUBTEST_5(test_cuda_igamma<double>());
   CALL_SUBTEST_5(test_cuda_igammac<double>());
+#endif
 }