@jsmaniac, thanks for your PR! By analyzing the history of the files in this pull request, we identified @Fuuzetsu, @aske and @globin to be potential reviewers.

The build fails with

/nix/store/[...]-SDL_mixer-1.2.12/include/SDL/SDL_mixer.h:27:23: fatal error: SDL_types.h: No such file or directory

Please consider enabling sandboxing to help eliminate implicit dependencies.

@joachifm I tried building it with nix-env -f $NIXPKGS --option nix.useSandbox true -iA crack_attack, and it build fine here (is that command okay? I couldn't find where to enable the useSandbox otherwise, /etc/nixos/configuration.nix complains that there is no such option if I add it there). Also, that file (SDL_types.h) is provided by the SDL package, which is already part of the build inputs for crack-attack. Any idea about what's happening here?

@jsmaniac if you're using nix-daemon, you can't control sandboxing that way (in a multi-user environment, some of the point of sandboxing would be lost if users could control it). Sandboxing is configured in nix.conf via nix.useSandbox or nix.useChroot if you're on an older NixOS.

One thing you could try something like NIX_CFLAGS_COMPILE = "-I${SDL.dev}/include" (or wherever the supposedly missing file resides); it's kind of ugly, but at least then you can ensure it'll be in the include path. Then again, adding SDL to inputs ought to be sufficient, if the headers are in a standard location ...

@joachifm Thanks for the help. I had omitted the nix. prefix when adding useSandbox to my /etc/nixos/configure.nix. I still can't reproduce the error, and noticed that on the Travis build, the following flags are omitted (but they are used when I build locally). I don't know why this happens, it's as if nix ignores some of the buildInputs.

-I/nix/store/3r7hrfi9ywgbx7wpv1kpjy8w2855p7ak-SDL-1.2.15-dev/include/SDL -I/nix/store/3r7hrfi9ywgbx7wpv1kpjy8w2855p7ak-SDL-1.2.15-dev/include/SDL -I/nix/store/lr4p15vdd35ixb3i1x1f25pf4k9aq75n-SDL_mixer-1.2.12/include/SDL -D_GNU_SOURCE=1 -D_REENTRANT

Several other games use the hack you mentioned, so I added this to crack-attack's default.nix too, this should hopefully be enough.

NIX_CFLAGS_COMPILE = "-I${SDL.dev}/include/SDL";