zig fetch doesnt work on Dawn packages

[cafeclimber]

So I saw #6 and read through. I didn't see anything explained in the README on how to deal with the dawn libs, but I tried as explained in the issue

Yes, Zig's package manager requires that you add all non-lazy dependencies and sub-dependencies to your build.zig.zon. You can manually copy the dependency entries out of the lib's build.zig.zon info your projects build.zig.zon, or give the URLs to zig fetch --save {url}.

Specifically I tried both doing zig fetch --save git+https://github.com/michal-z/webgpu_dawn-x86_64-windows-gnu.git

which gave this error

error: unable to determine name; fetched package has no build.zig.zon file

As well as just adding the deps manually to build.zig.zon by copying the relevant entries from the zgpu build.zig.zon.

This all arose from trying to use zgui so I hope I've chased this issue down to the right place 😅

[hazeycode]

Hi, can you confirm which version of Zig you are using?

[cafeclimber]

14.1

[hazeycode]

I will come back to this and fix the Dawn packages but in the meantime you should be able to work around this issue by manually adding dependencies to your build.zig.zon file

        .dawn_x86_64_windows_gnu = .{
            .url = "https://github.com/michal-z/webgpu_dawn-x86_64-windows-gnu/archive/d3a68014e6b6b53fd330a0ccba99e4dcfffddae5.tar.gz",
            .hash = "N-V-__8AAGsYnAT5RIzeAu881RveLghQ1EidqgVBVx10gVTo",
            .lazy = true,
        },

[cafeclimber]

Sorry Zig noob. Does this mean I would have to manually download those files and put them in my Zig cache?

edit:

I tried adding them by downloading the tarballs linked in the build.zig.zon of one of the zgui examples theen adding them to my build.zig.zon by doing

zig fetch --save=dawn_x86_64_linux_gnu ./libs/dawn/webgpu_dawn-x86_64-linux-gnu-7d70db023bf254546024629cbec5ee6113e12a42.tar.gz
...

which changed the url in my build.zig.zon to the local path but then a zig build said it was unable to find the .so files :(

[hazeycode]

No need to download the tarballs manually. Zig will download them to the cache when it reads your build.zig.zon.

It's the zig fetch code path that looks for a manifest so it knows what to call the entry in your build.zig.zon dependencies, which is why it works if you just manually add it.

[cafeclimber]

Gotcha. I do believe I tried that including a rm -rf .zig-cache to make sure everything was fresh but I get the following error on zig build

$ zig build
install
└─ install zes
   └─ zig build-exe zes Debug native failure
error: error: unable to find dynamic system library 'dawn' using strategy 'paths_first'. searched paths:
  /usr/local/lib/libdawn.so
  /usr/local/lib/libdawn.a
  /usr/lib/x86_64-linux-gnu/libdawn.so
  /usr/lib/x86_64-linux-gnu/libdawn.a
  /lib64/libdawn.so
  /lib64/libdawn.a
  /lib/libdawn.so
  /lib/libdawn.a
  /usr/lib64/libdawn.so
  /usr/lib64/libdawn.a
  /usr/lib/libdawn.so
  /usr/lib/libdawn.a
  /lib/x86_64-linux-gnu/libdawn.so
  /lib/x86_64-linux-gnu/libdawn.a
...

If it's helpful, this is my build.zig.zon

build.zig.zon

.{
    .name = .zes,
    .version = "0.0.0",
    .fingerprint = 0x77a18bf0ce9e6fe8, // Changing this has security and trust implications.
    .minimum_zig_version = "0.14.1",

    .dependencies = .{
        .zgui = .{
            .url = "git+https://github.com/zig-gamedev/zgui.git#21dcc288ac5ee70b1fca789d53a06d5c49d51e5e",
            .hash = "zgui-0.6.0-dev--L6sZKTBaADLHp09LtUUifdfFpsczwbnyH7r2ajfVPuJ",
        },
        .zglfw = .{
            .url = "git+https://github.com/zig-gamedev/zglfw.git#c337cb3d3f984468ea7a386335937a5d555fc024",
            .hash = "zglfw-0.10.0-dev-zgVDNMacIQA-k7kNSfwUc9Lfzx-bb_wklVm25K-p8Tr7",
        },
        .zgpu = .{
            .url = "git+https://github.com/zig-gamedev/zgpu.git#d860e2b4a333cacffb168fab49a233c5d2f1bca2",
            .hash = "zgpu-0.12.0-dev-nqFT5EKgCADkhwAf97_pfSOmPWEguKmljSECs9ihpFS7",
        },
        .dawn_x86_64_windows_gnu = .{
            .url = "https://github.com/michal-z/webgpu_dawn-x86_64-windows-gnu/archive/d3a68014e6b6b53fd330a0ccba99e4dcfffddae5.tar.gz",
            .hash = "N-V-__8AAGsYnAT5RIzeAu881RveLghQ1EidqgVBVx10gVTo",
            .lazy = true,
        },
        .dawn_x86_64_linux_gnu = .{
            .url = "https://github.com/michal-z/webgpu_dawn-x86_64-linux-gnu/archive/7d70db023bf254546024629cbec5ee6113e12a42.tar.gz",
            .hash = "N-V-__8AAK7XUQNKNRnv1J6i189jtURJKjp3HTftoyD4Y4CB",
            .lazy = true,
        },
        .dawn_aarch64_linux_gnu = .{
            .url = "https://github.com/michal-z/webgpu_dawn-aarch64-linux-gnu/archive/c1f55e740a62f6942ff046e709ecd509a005dbeb.tar.gz",
            .hash = "N-V-__8AAJ-wTwNc0T9oSflO92iO6IxrdMeRil37UU-KQD_M",
            .lazy = true,
        },
        .dawn_aarch64_macos = .{
            .url = "https://github.com/michal-z/webgpu_dawn-aarch64-macos/archive/d2360cdfff0cf4a780cb77aa47c57aca03cc6dfe.tar.gz",
            .hash = "N-V-__8AALVIRAIf5nfpx8-4mEo2RGsynVryPQPcHk95qFM5",
            .lazy = true,
        },
        .dawn_x86_64_macos = .{
            .url = "https://github.com/michal-z/webgpu_dawn-x86_64-macos/archive/901716b10b31ce3e0d3fe479326b41e91d59c661.tar.gz",
            .hash = "N-V-__8AAIz1QAKx8C8vft2YoHjGTjEAkH2QMR2UiAo8xZJ-",
            .lazy = true,
        },
    },

    .paths = .{
        "build.zig",
        "build.zig.zon",
        "src",
    },
}

and my build.zig

build.zig

const std = @import("std");

pub fn build(b: *std.Build) void {
    const target = b.standardTargetOptions(.{});
    const optimize = b.standardOptimizeOption(.{});

    const exe_mod = b.createModule(.{
        .root_source_file = b.path("src/main.zig"),
        .target = target,
        .optimize = optimize,
    });

    const exe = b.addExecutable(.{
        .name = "zes",
        .root_module = exe_mod,
    });

    const zgui = b.dependency("zgui", .{
        .shared = false,
        .with_implot = false,
    });
    exe.root_module.addImport("zgui", zgui.module("root"));
    exe.linkLibrary(zgui.artifact("imgui"));

    const zglfw = b.dependency("zglfw", .{});
    exe.root_module.addImport("zglfw", zglfw.module("root"));
    exe.linkLibrary(zglfw.artifact("glfw"));

    const zgpu = b.dependency("zgpu", .{});
    exe.root_module.addImport("zgpu", zgpu.module("root"));
    exe.linkLibrary(zgpu.artifact("zdawn"));

    b.installArtifact(exe);

    const run_cmd = b.addRunArtifact(exe);

    run_cmd.step.dependOn(b.getInstallStep());

    if (b.args) |args| {
        run_cmd.addArgs(args);
    }

    const run_step = b.step("run", "Run the app");
    run_step.dependOn(&run_cmd.step);

    const exe_unit_tests = b.addTest(.{
        .root_module = exe_mod,
    });

    const run_exe_unit_tests = b.addRunArtifact(exe_unit_tests);

    const test_step = b.step("test", "Run unit tests");
    test_step.dependOn(&run_exe_unit_tests.step);
}

[hazeycode]

Looks like you're now just missing @import("zgpu").addLibraryPathsTo(exe); in your build.zig

[cafeclimber]

So close 😭 Now I think I'm running into this issue. I attempted to use the workaround they mention and add .use_lld=false to the exe options but then I run into an ELF issue with Dawn. Not sure how close we are to being a non-zgpu issue but wanted to add the results I got.

Just to be clear about what I did, I added the line you mentioned to build.zig, rm -rf ~/.cache/zig .zig-cache zig-build added the use_lld=false bit and then rebuilt at which point I got

Build results

install
└─ install zes
   └─ zig build-exe zes Debug native 1 errors
error: invalid ELF machine type: ADAPTEVA_EPIPHANY
    note: while parsing /home/bailey/projects/zes/.zig-cache/o/e0d371d90734561b0c12172947234631/libzdawn.a
error: the following command failed with 1 compilation errors:
/home/bailey/.zig/14.1/zig build-exe -fno-lld /home/bailey/projects/zes/.zig-cache/o/103b0c72ec53f749e723d2a914491971/libimgui.a /home/bailey/projects/zes/.zig-cache/o/7b37160afca137c762b76d8741e0daa7/libglfw.a /home/bailey/projects/zes/.zig-cache/o/e0d371d90734561b0c12172947234631/libzdawn.a -ODebug -I /home/bailey/projects/zes/.zig-cache/o/efaed383166e26499e4003483132aafb -I /home/bailey/projects/zes/.zig-cache/o/62a835008135d754bec8875c5851b492 -I /home/bailey/projects/zes/.zig-cache/o/efaed383166e26499e4003483132aafb -L /home/bailey/.cache/zig/p/N-V-__8AAK7XUQNKNRnv1J6i189jtURJKjp3HTftoyD4Y4CB --dep zgui --dep zglfw --dep zgpu -Mroot=/home/bailey/projects/zes/src/main.zig --dep zgui_options -Mzgui=/home/bailey/.cache/zig/p/zgui-0.6.0-dev--L6sZKTBaADLHp09LtUUifdfFpsczwbnyH7r2ajfVPuJ/src/gui.zig -I /home/bailey/.cache/zig/p/zglfw-0.10.0-dev-zgVDNMacIQA-k7kNSfwUc9Lfzx-bb_wklVm25K-p8Tr7/libs/glfw/include -isystem /home/bailey/.cache/zig/p/system_sdk-0.3.0-dev-alwUNnYaaAJAtIdE2fg4NQfDqEKs7QCXy_qYukAOBfmF/linux/include -isystem /home/bailey/.cache/zig/p/system_sdk-0.3.0-dev-alwUNnYaaAJAtIdE2fg4NQfDqEKs7QCXy_qYukAOBfmF/linux/include/wayland --dep zglfw_options -Mzglfw=/home/bailey/.cache/zig/p/zglfw-0.10.0-dev-zgVDNMacIQA-k7kNSfwUc9Lfzx-bb_wklVm25K-p8Tr7/src/zglfw.zig --dep zgpu_options --dep zpool -Mzgpu=/home/bailey/.cache/zig/p/zgpu-0.12.0-dev-nqFT5EKgCADkhwAf97_pfSOmPWEguKmljSECs9ihpFS7/src/zgpu.zig -Mzgui_options=/home/bailey/projects/zes/.zig-cache/c/8ac9b3b2a841afcdfceb7bc14b484f05/options.zig -Mzglfw_options=/home/bailey/projects/zes/.zig-cache/c/6586df11eff312e117fbe01d06fb01a1/options.zig -Mzgpu_options=/home/bailey/projects/zes/.zig-cache/c/beb981d0bd05b0e87fc2a2902c7d35c9/options.zig -Mzpool=/home/bailey/.cache/zig/p/zpool-0.11.0-dev-bG692eY7AQDLTkjTbgnbg_-qgjmxUCg8hNpN1kZRrIlW/src/main.zig -lX11 -ldawn -lc++ -lc --cache-dir /home/bailey/projects/zes/.zig-cache --global-cache-dir /home/bailey/.cache/zig --name zes --zig-lib-dir /home/bailey/.zig/14.1/lib/ --listen=-
Build Summary: 9/12 steps succeeded; 1 failed
install transitive failure
└─ install zes transitive failure
   └─ zig build-exe zes Debug native 1 errors
error: the following build command failed with exit code 1:
/home/bailey/projects/zes/.zig-cache/o/ad569157d1c91fbfbd2d5e3280abaae5/build /home/bailey/.zig/14.1/zig /home/bailey/.zig/14.1/lib /home/bailey/projects/zes /home/bailey/projects/zes/.zig-cache /home/bailey/.cache/zig --seed 0xd6b29f0d -Z1f4fd1a155431be8

[hazeycode]

The first ELF error messages you refer to before changing anything can just be ignored, everything built well enough actually. Please don't change use_lld!

You'll see the same error messages if you build any of the zgpu sample apps in our dev repo but note they do successfully build and run despite this.

If you need any more help please feel free to ask in the discord -> https://discord.gg/SyjbjA5a

[cafeclimber]

Ah success! My nes emulator project can proceed!

Thanks so much for your help and pointing me to the discord!