In reply to @hexa:lossy.network
https://docs.nvidia.com/cuda/cuda-compiler-driver-nvcc/#nvcc-environment-variables

this doesn't work (nvidia-smi says my card is there etc). am i holding it wrong or is it broken?

$ nix develop
[snip]
$ nvcc foo.cu
In file included from /nix/store/fydjj6z3nyi1ywqbzzw7ai12ncjx9kwy-cuda-merged-12.2/include/cuda_runtime.h:82,
                 from <command-line>:
/nix/store/fydjj6z3nyi1ywqbzzw7ai12ncjx9kwy-cuda-merged-12.2/include/crt/host_config.h:143:2: error: #error -- unsupported GNU version! gcc versions later than 12 are not supported! The nvcc flag '-allow-unsupported-compiler' can be used to override this version check; however, using an unsupported host compiler may cause compilation failure or incorrect run time execution. Use at your own risk.
  143 | #error -- unsupported GNU version! gcc versions later than 12 are not supported! The nvcc flag '-allow-unsupported-compiler' can be used to override this version check; however, using an unsupported host compiler may cause compilation failure or incorrect run time execution. Use at your own risk.
      |  ^~~~~

flake.nix i am using as shell:

{
  description = "cuda development environment";
  inputs = {
    nixpkgs = {
      url = "github:NixOS/nixpkgs/4284c2b73c8bce4b46a6adf23e16d9e2ec8da4bb";
    };
  };
  outputs = { self, nixpkgs }:
    let
      system = "x86_64-linux";
      pkgs = import nixpkgs {
        inherit system;
        config.allowUnfree = true;
        config.cudaSupport = true;
      };
    in {
      devShells.${system}.default = pkgs.mkShell {
        buildInputs = with pkgs; [
          cudatoolkit linuxPackages.nvidia_x11
          cudaPackages.cudnn
          libGLU libGL
          xorg.libXi xorg.libXmu freeglut
          xorg.libXext xorg.libX11 xorg.libXv xorg.libXrandr zlib 
          ncurses5 stdenv.cc binutils
        ];

        shellHook = ''
              export LD_LIBRARY_PATH="${pkgs.linuxPackages.nvidia_x11}/lib"
          '';          
      };
    };
}

$ nix-shell -p gcc12 --run 'gcc --version'
gcc (GCC) 13.3.0
Copyright (C) 2023 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

That seems wrong. I get that, too. Also,

❯ nix-shell -p gcc12 --run 'which gcc'
/nix/store/mpm3i0sbqc9svfch6a17179fs64dz2kv-gcc-wrapper-13.3.0/bin/gcc

❯ nix-shell -p gcc12 --run 'echo $PATH' | rg gcc
...:/nix/store/mpm3i0sbqc9svfch6a17179fs64dz2kv-gcc-wrapper-13.3.0/bin:...:/nix/store/7hqg1pzya6xjp6vri2fsfjnf4w622p7w-gcc-wrapper-12.3.0/bin:...

Compare this to nix3-shell:

❯ nix shell nixpkgs#gcc12 --command which gcc
/nix/store/7hqg1pzya6xjp6vri2fsfjnf4w622p7w-gcc-wrapper-12.3.0/bin/gcc

In reply to @ornx:littledevil.club
i'm having a lot of trouble getting things working still - i'm using devShell.override with cudaPackages.backendStdenv and cuda programs compile and run with nvcc, but i'm getting a cudaErrorInsufficientDriver error even though i'm building my flake against the same revision of nixpkgs that the system was built against