Pin toolchain to a fixed channel and add an enforced lint gate

.github/workflows/crates.yml

@@ -160,11 +160,13 @@ jobs:
       with:
         save-if: ${{ github.ref == 'refs/heads/main' }}
 
+    # Advisory only (no -D warnings) — the enforced gate lives in lint.yml.
     - run: rustup component add clippy && cargo clippy --all-targets
     - name: clippy (bench-suite feature)
       run: cargo clippy -p tract-cli --features bench-suite
     - name: test (bench-suite feature)
       run: cargo test -p tract-cli --features bench-suite --bin tract bench_
+    # Enforced fmt check also runs in lint.yml; kept here too for this job's own gating.
     - name: fmt
       run: rustup component add rustfmt --toolchain stable && cargo +stable fmt --check
     - name: Warnings

.github/workflows/lint.yml

@@ -0,0 +1,55 @@
+name: lint
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+permissions:
+  contents: read
+
+concurrency:
+  group: lint-${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+env:
+  CARGO_INCREMENTAL: false
+  CARGO_NET_RETRY: 10
+
+jobs:
+  format:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      # `rustup show` installs and activates whatever `rust-toolchain.toml`
+      # pins, so the version lives in exactly ONE place. This is also the
+      # repo's own idiom — the other workflows drive rustup directly rather
+      # than through a third-party toolchain action.
+      - name: Setup rust toolchain (pinned by rust-toolchain.toml)
+        run: |
+          rustup show
+          rustup component add rustfmt
+
+      - run: cargo fmt --all --check
+
+  clippy:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Setup rust toolchain (pinned by rust-toolchain.toml)
+        run: |
+          rustup show
+          rustup component add clippy
+
+      - uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
+        with:
+          save-if: ${{ github.ref == 'refs/heads/main' }}
+
+      - run: cargo clippy --all-targets -- -D warnings

Cargo.toml

@@ -124,7 +124,7 @@ default-members = [
 [workspace.package]
 # MSRV source of truth: CI derives the tested toolchain from this. Keep the
 # README rustc badge in sync when bumping.
-rust-version = "1.97"
+rust-version = "1.98"
 
 [workspace.dependencies]
 anstyle = "1.0.2"

README.md

@@ -1,7 +1,7 @@
 ![tract-logo](assets/tract-logo/PNG/tract-horizontal-blue.png)
 
 ![Rust](https://img.shields.io/badge/rust-%23000000.svg?style=for-the-badge&logo=rust&logoColor=white)
-![rustc >= 1.97.0](https://img.shields.io/badge/rustc-%3E%3D1.97.0-brightgreen)
+![rustc >= 1.98.0](https://img.shields.io/badge/rustc-%3E%3D1.98.0-brightgreen)
 ![MIT/Apache 2](https://img.shields.io/crates/l/tract)
 [![Native Linux test status](https://github.com/sonos/tract/workflows/Native%20Linux/badge.svg)](https://github.com/sonos/tract/actions)
 [![Embedded targets status](https://github.com/sonos/tract/workflows/Embedded%20targets/badge.svg)](https://github.com/sonos/tract/actions)

cli/src/hwbench.rs

@@ -385,6 +385,10 @@ fn llc_bytes() -> usize {
     max.unwrap_or(32 * 1024 * 1024)
 }
 
+// The arguments ARE the benchmarked shape — datum type plus the GEMM's own
+// dimensions. Folding them into a parameter struct would name the same eight
+// values one indirection away without making any call site clearer.
+#[allow(clippy::too_many_arguments)]
 fn bench_shape(
     dt: DatumType,
     m: usize,

linalg/src/arm32/mod.rs

@@ -47,15 +47,15 @@ fn neon_mmv_f32(suitable: &[Suitable], query: &Query) -> Option<&'static str> {
             Some(m) if m < 32 => {
                 cortex_a7_mmv_linear::linear_model().preferred(suitable, Some(m), query.k, Some(1))
             }
-            _ => Some(&armv7neon::armv7neon_mmm_f32_32x1_cortexa7.name.as_str()),
+            _ => Some(armv7neon::armv7neon_mmm_f32_32x1_cortexa7.name.as_str()),
         },
         0xc09 => match query.m {
             Some(m) if m < 32 => {
                 cortex_a9_mmv_linear::linear_model().preferred(suitable, Some(m), query.k, Some(1))
             }
-            _ => Some(&armv7neon::armv7neon_mmm_f32_32x1_cortexa9.name.as_str()),
+            _ => Some(armv7neon::armv7neon_mmm_f32_32x1_cortexa9.name.as_str()),
         },
-        _ => Some(&armv7neon::armv7neon_mmm_f32_32x1_generic.name.as_str()),
+        _ => Some(armv7neon::armv7neon_mmm_f32_32x1_generic.name.as_str()),
     }
 }
 
@@ -80,8 +80,8 @@ fn preferred(
     match (dt, query.n) {
         (DatumType::F32, Some(1)) => neon_mmv_f32(suitable, query),
         (DatumType::F32, _) => neon_mmm_f32(suitable, query),
-        (DatumType::I32, Some(1)) => Some(&armv7neon::armv7neon_mmm_i32_32x1.name.as_str()),
-        (DatumType::I32, _) => Some(&armv7neon::armv7neon_mmm_i32_8x4.name.as_str()),
+        (DatumType::I32, Some(1)) => Some(armv7neon::armv7neon_mmm_i32_32x1.name.as_str()),
+        (DatumType::I32, _) => Some(armv7neon::armv7neon_mmm_i32_8x4.name.as_str()),
         _ => None,
     }
 }

linalg/src/generic/reduce.rs

@@ -227,16 +227,16 @@ pub mod softmax_l2 {
     #[inline]
     fn exp_sum_impl(x: &mut [f32], max: f32) -> f32 {
         let mut acc = [0f32; 4];
-        let mut it = x.chunks_exact_mut(4);
-        for c in &mut it {
+        let (chunks, remainder) = x.as_chunks_mut::<4>();
+        for c in chunks.iter_mut() {
             for (j, v) in c.iter_mut().enumerate() {
                 let y = accurate_exp_f32(*v - max);
                 *v = y;
                 acc[j] += y;
             }
         }
         let mut sum = (acc[0] + acc[1]) + (acc[2] + acc[3]);
-        for v in it.into_remainder().iter_mut() {
+        for v in remainder.iter_mut() {
             let y = accurate_exp_f32(*v - max);
             *v = y;
             sum += y;

linalg/src/x86_64/mmm.rs

@@ -490,7 +490,7 @@ fn avx2_preferred(
 ) -> Option<&'static str> {
     match (dt, query.n) {
         (DatumType::I32, Some(1)) => None,
-        (DatumType::I32, _) => Some(&mmm::avx2_mmm_i32_8x8.name.as_str()),
+        (DatumType::I32, _) => Some(mmm::avx2_mmm_i32_8x8.name.as_str()),
         _ => None,
     }
 }

rust-toolchain.toml

@@ -1,3 +1,7 @@
+# Bump log (append-only):
+# - 2026-09-05: pinned to a fixed channel (was floating "stable"), joining
+#   the workspace-wide Rust toolchain sweep. A future bump edits only the
+#   `channel` line below — the version lives in exactly one place.
 [toolchain]
-channel = "stable"
+channel = "1.98.1"
 components = ["rustfmt", "clippy"]

transformers/src/ops/gdn_recurrent.rs

@@ -211,6 +211,10 @@ mod tests {
     use super::*;
     use crate::ops::test_utils::arb;
 
+    // A test helper whose arguments are the layer's own inputs: three shape
+    // values and the six tensors the operator consumes. Grouping them would
+    // obscure exactly what each case is feeding in.
+    #[allow(clippy::too_many_arguments)]
     fn run(
         s_len: usize,
         heads: usize,