Image store parameters are invalid - Not a global variable

[pyranota]

Expected Behaviour

Naga validation to succeed, shader to be executed by bevy

Example & Steps To Reproduce

1. Set up simple shader using texture store:

#[inline(never)]
#[spirv(compute(threads(8, 8, 1)))]
pub fn main(
    #[spirv(global_invocation_id)] id: UVec3,
    #[spirv(descriptor_set = 0, binding = 1)] image2d: &Image!(
        2D,
        format = rgba32f,
        sampled = false
    ),
) {
    unsafe {
        image2d.write(ivec2(1, 1), vec4(3., 2., 1., 0.));
    }
}

2. Compile
3. naga /../shader/path.spv (or use it in bevy_render)

I'm using rust-gpu main branch, spirv-unknown-vulkan1.4 as a target in build.rs, but the error is the same as far as I can tell.

Not sure if bevy reproduction set up is needed, as it fails with same error naga validation does. Something makes me think it is related to incorrect spv gen

System Info

• Rust: rustc 1.90.0-nightly (35f603652 2025-06-29)
• OS: NixOS
• GPU: AMD Radeon 890M
• SPIR-V: SPIRV-Tools v2025.5 unknown hash

Backtrace

[2026-02-03T15:08:12Z INFO  naga::front::spv] Generated by 983040 version 10600
[2026-02-03T15:08:12Z INFO  naga::front::spv] Patching...
Function [0] '' is invalid:
	Image store parameters are invalid
	Not a global variable

[Firestar99]

Since spirv-val succeeds, it's more likely that naga is just failing to parse that spirv. Which is not surprising, there's quite a lot of spirv naga can't parse. (See pipelines in #493 failing cause naga can't understand some spirv)

You can try to use type=f32 instead of format = rgba32f, like in this alias?

rust-gpu/crates/spirv-std/src/image.rs

Line 68 in ba15d4c

pub type StorageImage2d = crate::Image!(2D, type=f32, sampled=false, __crate_root=crate);

You may also need these extra capabilities, set them via SpirvBuilder.capability:

Capability::StorageImageExtendedFormats,
Capability::StorageImageReadWithoutFormat,
Capability::StorageImageWriteWithoutFormat,

[pyranota]

Thanks for the fast response! I guess in bevy case (it uses naga) I should compile it to something naga understands. Using unknown format for texture and setting capabilities yields the same result (with couple of warnings about unrecognized caps):

[2026-02-03T15:36:47Z INFO  naga::front::spv] Generated by 983040 version 10600
[2026-02-03T15:36:47Z WARN  naga::front::spv] Unknown capability StorageImageReadWithoutFormat
[2026-02-03T15:36:47Z WARN  naga::front::spv] Unknown capability StorageImageWriteWithoutFormat
[2026-02-03T15:36:47Z INFO  naga::front::spv] Patching...
Function [0] '' is invalid:
	Image store parameters are invalid
	Not a global variable

[Firestar99]

Just double checked our compiletest, and while we have one that passes for texel fetches (just make sure to fetch with a lod level, don't use fetch until #490 is merged), none of the image write tests do actually pass for one reason or another. All of my use-cases with naga transpilation to wgsl were only fragment shaders, so never had to write texels either.

[pyranota]

Can confirm it has exactly the same error here: https://github.com/Rust-GPU/rust-gpu/actions/runs/20504878075/job/58917828710?pr=493#step:6:3598

I wonder if it's nagas responsibility, as rust-gpu emits valid spir-v and naga strays to have first class support for it?