gfx-rs/wgpu · critical

Timestamp normalization requires the wgsl feature flag to be

Error message

Timestamp normalization requires the wgsl feature flag to be enabled!

What it means

wgpu-core's timestamp normalization pass rewrites timestamp query results using a generated WGSL shader, so it needs the naga `wgsl` feature to build/validate that module. If the crate was compiled without the `wgsl` feature while TIMESTAMP_QUERY-inside-passes support is requested, this panic fires in the device/adapter initialization path.

Source

Thrown at wgpu-core/src/timestamp_normalization/mod.rs:151

                })?;

            let common_src = include_str!("common.wgsl");
            let src = include_str!("timestamp_normalization.wgsl");

            let preprocessed_src = alloc::format!("{common_src}\n{src}");

            #[cfg(feature = "wgsl")]
            let module = naga::front::wgsl::parse_str(&preprocessed_src).map_err(|inner| {
                TimestampNormalizerInitError::ParseWgsl(naga::error::ShaderError {
                    source: preprocessed_src.clone(),
                    label: None,
                    inner: Box::new(inner),
                })
            })?;
            #[cfg(not(feature = "wgsl"))]
            #[allow(clippy::diverging_sub_expression)]
            let module =
                panic!("Timestamp normalization requires the wgsl feature flag to be enabled!");

            let info = crate::device::create_validator(
                wgt::Features::IMMEDIATES,
                wgt::DownlevelFlags::empty(),
                naga::valid::ValidationFlags::all(),
            )
            .validate(&module)
            .map_err(|inner| {
                TimestampNormalizerInitError::ValidateWgsl(naga::error::ShaderError {
                    source: preprocessed_src.clone(),
                    label: None,
                    inner,
                })
            })?;
            let hal_shader = hal::ShaderInput::Naga(hal::NagaShader {
                module: alloc::borrow::Cow::Owned(module),
                info,
                debug_source: None,

View on GitHub (pinned to 3e11ff59bf)

Solutions

1. Enable the `wgsl` feature on the wgpu/wgpu-core dependency in Cargo.toml: features = ["wgsl"].
2. Alternatively disable timestamp query usage (remove Features::TIMESTAMP_QUERY) so normalization is not needed.
3. Rebuild with `cargo build` after changing features and verify with `cargo tree -f` that naga is built with the wgsl backend.

Example fix

// before (Cargo.toml)
wgpu-core = { version = "25", default-features = false }
// after
wgpu-core = { version = "25", features = ["wgsl"] }

#[cfg(not(feature = "wgsl"))]
compile_error!("timestamp query usage requires the wgsl feature");

When it happens

Trigger: Creating a device/queue with timestamp normalization enabled (e.g. features containing TIMESTAMP_QUERY with the internal normalization path) while the wgpu-core build lacks feature `wgsl`; enabling timestamp queries in a custom wgpu feature set that excludes wgsl.

Common situations: Custom builds of wgpu with minimal cargo features; vendored or forked builds trimming naga backends; upgrading wgpu and adding timestamp query usage without re-enabling the wgsl feature flag.

Related errors

• wgpu error: {err}
• Mismatched pop_error_scope call: no error scope for this thr
• Mismatched pop_error_scope call: error scopes must be popped
• Attempted to create a static DXC shader compiler, but the st
• ${name} is not webgpu

AI-assisted analysis of gfx-rs/wgpu@3e11ff59bf (2026-09-03). Data as JSON: /api/errors/4c1fa6b0497fc74b. Report an issue: GitHub.