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Date: Mon, 17 Sep 2018 16:00:26 +0200
From: Guilherme Amadio <amadio@gentoo.org>
To: gentoo-dev@lists.gentoo.org
Subject: [gentoo-dev] [RFC] Make 'cuda' a global USE flag
Message-ID: <20180917135849.GA28786@gentoo.org>
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Hi everyone,

We have several packages (~35) with local USE=cuda. Should we make that
a global USE flag? It's a quite generic flag for GPU support, so I was
surprised to learn it was still local when I added support for it to a
package recently.

Another thing we might want to discuss is a global setting for the CUDA
architecture to be used¹. We compile from source, so it would be a shame
not to compile with the right features for newer GPUs². Maybe just
advertising the NVCCFLAGS one should put in make.conf is enough?

Cheers,
—Guilherme

1. https://docs.nvidia.com/cuda/cuda-compiler-driver-nvcc/index.html#options-for-steering-gpu-code-generation
2. https://docs.nvidia.com/cuda/cuda-compiler-driver-nvcc/index.html#gpu-feature-list