OpenACC in GCC - how does it not violate the license?

[Jeff Law]

On 11/16/13 21:58, Alec Teal wrote:
> Now while great, is this true!? Nvidia (IIRC, this was like a year ago
> though) don't even give out the instruction set for their GPUs, can we
> have GCC targeting closed things? Also there (must be and is) a Cuda
> runtime, wouldn't we need an open runtime to link against?
The various projects looking at supporting OpenACC are, to the best of 
my knowledge, targeting PTX, which is a virtual ISA from NVidia which is 
published.

Going from PTX to the actual instructions for the particular GPU is the 
job of a runtime system which would be provided by NVidia.

However, there's no reason why OpenACC couldn't target the host CPU or 
another GPU.  In fact, that's what I'd initially do if I were working on 
this.

>
> This is by no means an accusation, I'm sure he's doing fine work; but
> he's doing something I didn't think the GPLv3 allowed (so I want to be
> corrected) he seems to have added something that requires a closed
> runtime for a target with a closed instruction set - probably for Nvidia
> (as he is responsible for "strategic partnerships" with them)
To answer that question you'd need to talk to your lawyer.

jeff