Compilation breaks on latest revision

[Makogan]

Expected Behaviour

Compiling valid rustgpu code

Example & Steps To Reproduce

I have some shaders that used to compile on revision 2aa4d4f8a8ba73103501562cfca17b8163e5a887, On revision 08f98a7335ae7e2ac4ec9423a9b1acf9270f2a65 they no longer compile with this error.

    Caused by:
      process didn't exit successfully: `/home/makogan/.rustup/toolchains/nightly-2025-06-30-x86_64-unknown-linux-gnu/bin/rustc - --crate-name ___ --print=file-names -Zcodegen-backend=/home/makogan/.cache/rust-gpu/codegen/https___github_com_Rust-GPU_rust-gpu_+08f98a73/librustc_codegen_spirv.so -Zbinary-dep-depinfo -Csymbol-mangling-version=v0 '-Zcrate-attr=feature(register_tool)' '-Zcrate-attr=register_tool(rust_gpu)' -Coverflow-checks=off -Cdebug-assertions=off -Zinline-mir=off -Zmir-enable-passes=-GVN -Zshare-generics=off '-Cllvm-args=--module-output=multiple --spirv-metadata=full' --target /home/makogan/.cache/rust-gpu/codegen/https___github_com_Rust-GPU_rust-gpu_+08f98a73/target-specs/spirv-unknown-vulkan1.2.json --crate-type bin --crate-type rlib --crate-type dylib --crate-type cdylib --crate-type staticlib --crate-type proc-macro --print=sysroot --print=split-debuginfo --print=crate-name --print=cfg -Wwarnings` (exit status: 1)
      --- stderr
      error: error loading target specification: `unknown` os can only be used on particular targets; use `none` for bare-metal targets
        |
        = help: run `rustc --print target-list` for a list of built-in targets

    [2026-01-17T19:38:56Z ERROR cargo_gpu] build failed
    Error: build failed

Based on the error it seems like some type has been changed to use an option and it's not receiving the expected option.

System Info

rustc 1.94.0-nightly (c61a3a44d 2025-12-09)
arch linux
RTX 4070
SPIR-V 1.6 (under Vulkan 1.3 semantics) SPIR-V 1.6 (under Vulkan 1.4 semantics)

[Makogan]

A more recent commit that I can verify compiles is e97524f6b4816056b3edaa70c3e0e0c656392c05

[Firestar99]

That error is caused by incorrect "target spec" aka target specification json files. This is something you as an end user shouldn't have to worry about, as spirv-builder and cargo-gpu will take care of that for you.

Which begs the question: are you using cargo-gpu via the cmdline, cargo-gpu in a build script or spirv-builder directly? And if cargo-gpu, which version?

[Firestar99]

We recently changed target spec handling, but it shouldn't have broken anything eg. for an older cargo-gpu version until we update target specs again: #484

Both suggested working revs are before this PR was merged.

[Makogan]

That error is caused by incorrect "target spec" aka target specification json files. This is something you as an end user shouldn't have to worry about, as spirv-builder and cargo-gpu will take care of that for you.

Which begs the question: are you using cargo-gpu via the cmdline, cargo-gpu in a build script or spirv-builder directly? And if cargo-gpu, which version?

I am invoking cargo gpu through the command interface of a rust program. I am using cargo-gpu 0.1.0