nvidia-cuda-toolkit: nvcc needs to pass -fpie to compiler

[Matthias Klose]

On 15.05.2017 02:06, Lumin wrote:
> @doko GCC-5 may be removed from unstable when CUDA 9.0
> is uploaded. See below.

[I'd like to reach gcc-5 5.5 reach snapshot.debian.org, which will be around
June/July. Then we can remove it].

> (Maybe doko is already in some of these lists.)
> 
>> The problem is the move of some parts of the toolchain to pie by
>> default, without updating the whole toolchain. Whenever not using only
>> gcc for building object files, the issue shows up. nvcc is only an
>> example of this.
> 
> Yes, toolchain problem. Due to the difference on the default option,
> the mixed use of GCC and CLANG may end up with a failure as shown
> in previous examples. This issue is not related to CUDA so I think
> another bug against clang should be submitted.

are you sure that this is every toolchain? ghc, and other compilers aren't
changed either.  Also wouldn't turning on pie on clang sadden the clang
benchmarks ;)

>>> And what can we do from the CUDA packaging side except for a new
>>> NEWS/README.Debian section?
>>>
>> That's probably a reasonable thing to do on that side, yes.
> 
> The good news is that, the upcoming CUDA 9.0 supports GCC-6
> and CLANG-3.9, as reported here
> 
>   https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=862522
> 
> That means, the "build your whole application with clang-3.8"
> advise is temporary and specific to CUDA 8.0. Before uploading
> CUDA 9.0 to unstable/experimental, we can change the default
> compiler back to GCC. And backporting CUDA 9.0 to stretch
> will eliminate the compiler trouble.

It would be interesting to know how GCC 7 plays along with CUDA 9.0

Matthias