Torch 7 with CUDA 10 on Ubuntu

Torch 7 fails with CUDA 10 by producing below error:

/build/torch7-cutorch-git/src/torch7-cutorch-git/lib/THC/THCAtomics.cuh(97): error: cannot overload functions distinguished by return type alone

1 error detected in the compilation of "/run/user/1000/tmpxft_00007438_00000000-4_THCTensorIndex.cpp4.ii".
CMake Error at THC_generated_THCTensorIndex.cu.o.Release.cmake:279 (message):
  Error generating file
  /build/torch7-cutorch-git/src/torch7-cutorch-git/lib/THC/CMakeFiles/THC.dir//./THC_generated_THCTensorIndex.cu.o

It has two issues:

1. cmake/3.6/Modules/FindCUDA.cmake is outdated.
2. atomicAdd(__half *address, __half val) is defined in /usr/local/cuda/include/cuda_fp16.h (duplicated).

Step 1: Install the latest CMake from github repo.

$ sudo apt-get purge cmake
$ git clone https://github.com/Kitware/CMake.git
$ cd CMake
$ ./bootstrap; make; sudo make install

The master branch of cuDNN.torch does not support cuDNN v7. Installing from R7 branch probably works fine.

$ git clone https://github.com/soumith/cudnn.torch.git -b R7
$ cd cudnn.torch
$ luarocks make cudnn-scm-1.rockspec

Step 2: Remove FindCUDA.cmake.

$ cd ~/torch
$ rm -fr cmake/3.6/Modules/FindCUDA*

Step 3: Apply the following patch to cutorch

diff --git a/lib/THC/THCAtomics.cuh b/lib/THC/THCAtomics.cuh
index 400875c..ccb7a1c 100644
--- a/lib/THC/THCAtomics.cuh
+++ b/lib/THC/THCAtomics.cuh
@@ -94,6 +94,7 @@ static inline __device__ void atomicAdd(long *address, long val) {
 }
 
 #ifdef CUDA_HALF_TENSOR
+#if !(__CUDA_ARCH__ >= 700 || !defined(__CUDA_ARCH__) )
 static inline  __device__ void atomicAdd(half *address, half val) {
   unsigned int * address_as_ui =
       (unsigned int *) ((char *)address - ((size_t)address & 2));
@@ -117,6 +118,7 @@ static inline  __device__ void atomicAdd(half *address, half val) {
    } while (assumed != old);
 }
 #endif
+#endif

$ cd extra/cutorch
$ cat > atomic.patch
<copy and paste the patch>
$ patch -p1 < atomic.patch

Step 4: Build it.

$ ./clean.sh
$ export TORCH_NVCC_FLAGS="-D__CUDA_NO_HALF_OPERATORS__"
$ ./install.sh

Let me know if this helps !!