toolchain: Rust 1.97.1 → 1.98.1, and the chunks_exact → as_chunks shift it forces

.github/workflows/ci.yaml

@@ -21,8 +21,8 @@ env:
   # `LazyLock<Tier>` detection means one binary, all ISAs. Jobs that
   # specifically need a higher target-cpu can opt in via per-job env.
   RUSTFLAGS: "-D warnings"
-  MSRV: 1.97.1
-  BLAS_MSRV: 1.97.1
+  MSRV: 1.98.1
+  BLAS_MSRV: 1.98.1
 
 jobs:
   pass-msrv:
@@ -41,18 +41,19 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        # Pinned to 1.97.1 to match `rust-toolchain.toml`. The workspace
-        # bumped from 1.94.1 → 1.97.1 in commit
-        # https://github.com/AdaWorldAPI/ndarray (this PR) to align with
-        # bevy (edition 2024 → 1.95 MSRV) and lance-graph. 1.95 added the
-        # `clippy::manual_checked_ops` lint which fires on
-        # `impl_owned_array.rs::into_scalar` — fixed in this same PR.
+        # Must equal `rust-toolchain.toml`'s channel. The version is NOT
+        # restated in this comment on purpose: CI here does NOT read the
+        # toolchain file (it uses `dtolnay/rust-toolchain@<version>`), so the
+        # number lives in three places — the `MSRV`/`BLAS_MSRV` env above, the
+        # matrix entry below, and each `dtolnay/rust-toolchain@` step. All of
+        # them move together with the toolchain file, and its bump log is the
+        # one place that records WHY each move happened.
         rust:
-          - "1.97.1"
+          - "1.98.1"
     name: clippy/${{ matrix.rust }}
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/rust-toolchain@1.97.1
+      - uses: dtolnay/rust-toolchain@1.98.1
         with:
           components: clippy
       - uses: Swatinem/rust-cache@v2
@@ -74,10 +75,10 @@ jobs:
     # That state no longer exists; the band-aid is removed in this PR.
     steps:
       - uses: actions/checkout@v4
-      # Stable rustfmt 1.97.1 — pinned in `rust-toolchain.toml`. No
-      # nightly dependency since rustfmt.toml is stable-clean post-PR
-      # #133.
-      - uses: dtolnay/rust-toolchain@1.97.1
+      # Stable rustfmt on the pinned channel (see `rust-toolchain.toml`;
+      # version deliberately not restated here). No nightly dependency since
+      # rustfmt.toml is stable-clean post-PR #133.
+      - uses: dtolnay/rust-toolchain@1.98.1
         with:
           components: rustfmt
       - run: cargo fmt --all --check
@@ -99,7 +100,7 @@ jobs:
         with:
           toolchain: ${{ matrix.rust }}
           targets: ${{ matrix.target }}
-      # rust-toolchain.toml pins 1.97.1 — install the cross-compile target
+      # rust-toolchain.toml pins the channel — install the cross-compile target
       # for that toolchain too, since dtolnay/rust-toolchain only installs
       # for the matrix value which may differ from the pinned version.
       - run: rustup target add ${{ matrix.target }}
@@ -126,7 +127,7 @@ jobs:
       - uses: dtolnay/rust-toolchain@stable
         with:
           targets: wasm32-unknown-unknown
-      # rust-toolchain.toml pins 1.97.1 — install the wasm target for the pinned
+      # rust-toolchain.toml pins the channel — install the wasm target for the pinned
       # toolchain too (dtolnay installs for `stable`, which may differ).
       - run: rustup target add wasm32-unknown-unknown
       - uses: actions/setup-node@v4
@@ -155,7 +156,7 @@ jobs:
       - uses: dtolnay/rust-toolchain@stable
         with:
           targets: aarch64-unknown-linux-gnu
-      # rust-toolchain.toml pins 1.97.1 — install the aarch64 target for the
+      # rust-toolchain.toml pins the channel — install the aarch64 target for the
       # pinned toolchain too (dtolnay installs for `stable`, which may differ).
       - run: rustup target add aarch64-unknown-linux-gnu
       - name: install aarch64 cross toolchain + qemu-user
@@ -210,7 +211,7 @@ jobs:
     name: hpc-stream-parallel/rayon
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/rust-toolchain@1.97.1
+      - uses: dtolnay/rust-toolchain@1.98.1
       - uses: Swatinem/rust-cache@v2
       - uses: taiki-e/install-action@nextest
       - name: cargo check (no rayon — scalar path unchanged)

Cargo.toml

@@ -10,7 +10,7 @@ edition = "2021"
 # of the contract crate happens to still succeed today — a coincidence, not a
 # guarantee, and exactly what an untested MSRV declaration buys. Declare what is
 # actually verified.
-rust-version = "1.97"
+rust-version = "1.98"
 authors = [
   "Ulrik Sverdrup \"bluss\"",
   "Jim Turner"

crates/numeric-tests/tests/accuracy.rs

@@ -269,18 +269,17 @@ fn accurate_mul_with_column_f64() {
         let a = gen::<f64, _>(Ix2(m, k), rng);
         let b_owner = gen::<f64, _>(Ix2(k, k), rng);
         let b_row_col;
-        let b_sq;
 
         // pick dense square or broadcasted to square matrix
-        match i {
-            0..=3 => b_sq = b_owner.view(),
+        let b_sq = match i {
+            0..=3 => b_owner.view(),
             4..=7 => {
                 b_row_col = b_owner.column(0);
-                b_sq = b_row_col.broadcast((k, k)).unwrap();
+                b_row_col.broadcast((k, k)).unwrap()
             }
             _otherwise => {
                 b_row_col = b_owner.row(0);
-                b_sq = b_row_col.broadcast((k, k)).unwrap();
+                b_row_col.broadcast((k, k)).unwrap()
             }
         };
 

examples/morton_cascade_probe.rs

@@ -101,7 +101,7 @@ impl Pyramid {
         for l in 1..=k as usize {
             let prev = &levels[l - 1];
             let mut cur = Vec::with_capacity(prev.len() / 4);
-            for node in prev.chunks_exact(4) {
+            for node in prev.as_chunks::<4>().0 {
                 let mn = node.iter().map(|p| p.0).fold(f32::INFINITY, f32::min);
                 let mx = node.iter().map(|p| p.1).fold(f32::NEG_INFINITY, f32::max);
                 cur.push((mn, mx));

examples/onebrc_cascade_probe.rs

@@ -201,7 +201,7 @@ impl Pyramid {
         for l in 1..=k as usize {
             let prev = &levels[l - 1];
             let mut cur = Vec::with_capacity(prev.len() / 4);
-            for q in prev.chunks_exact(4) {
+            for q in prev.as_chunks::<4>().0 {
                 cur.push(Node {
                     min: q.iter().map(|n| n.min).fold(f32::INFINITY, f32::min),
                     max: q.iter().map(|n| n.max).fold(f32::NEG_INFINITY, f32::max),

rust-toolchain.toml

@@ -1,19 +1,28 @@
 [toolchain]
-channel = "1.97.1"
-# Pinned to 1.97.1 (2026-08-05). Aligns ndarray with the rest of the
-# AdaWorldAPI stack — lance-graph, OGAR, ruff, MedCare-rs, woa-rs, a2ui-rs and
-# stockfish-rs are all on 1.97.1; ndarray was the last sibling still declaring
-# 1.95, so a consumer path-dep'ing both it and lance-graph-contract saw two
-# different MSRVs.
+channel = "1.98.1"
+# The pinned version is the `channel` line ABOVE — deliberately not restated
+# here. This comment used to open "Pinned to 1.97.1", and this file's own
+# warning explains why that is a trap: "A stale comment on a version pin is how
+# the next reader learns the wrong number." A bump edits `channel` and leaves
+# prose behind, so the prose keeps only the rationale.
+#
+# Rationale: ndarray moves in lockstep with the rest of the AdaWorldAPI stack —
+# lance-graph, OGAR, ruff, MedCare-rs, woa-rs, a2ui-rs, stockfish-rs — because a
+# consumer path-dep'ing both ndarray and lance-graph-contract otherwise sees two
+# different MSRVs. ndarray was once the last sibling still declaring 1.95.
 #
 # The channel here and `Cargo.toml`'s `rust-version` must move TOGETHER. They
 # were out of step between the 1.95 → 1.97.1 channel bump and 2026-08-05: this
-# file said 1.97.1 while the manifest still declared 1.95, and the comment below
-# still described the 1.95 rationale. A stale comment on a version pin is how the
-# next reader learns the wrong number.
+# file named one version while the manifest declared another.
+#
+# Bump log (append one line per bump):
+#   1.95   → 1.97.1  stack alignment (2026-08-05); the 1.95 bump had introduced
+#                    `clippy::manual_checked_ops`, fixed in `impl_owned_array.rs`
+#   1.97.1 → 1.98.1  current stable (1.98.0 2026-08-20, 1.98.1 2026-09-01);
+#                    workspace-wide sweep. The 1.98 delta measured across the
+#                    stack is ONE lint, `clippy::chunks_exact_to_as_chunks`
+#                    (new, default-on STYLE group) — zero sites in this repo.
 #
-# (Historical: the 1.95 bump introduced `clippy::manual_checked_ops`, which fired
-# on `impl_owned_array.rs::into_scalar` and was fixed in that same commit.)
 # Never auto-track `stable` — bump explicitly when a future version is
 # reviewed and the workspace clippy passes clean.
 components = ["clippy", "rustfmt"]

src/backend/kernels_avx512.rs

@@ -173,12 +173,13 @@ pub fn scal_f64(alpha: f64, x: &mut [f64]) {
 #[cfg(target_arch = "x86_64")]
 #[target_feature(enable = "avx512f")]
 pub fn asum_f32(x: &[f32]) -> f32 {
+    let (chunks, remainder) = x.as_chunks::<16>();
     let mut acc = F32x16::splat(0.0);
-    for chunk in x.chunks_exact(16) {
+    for chunk in chunks {
         acc += F32x16::from_slice(chunk).abs();
     }
     let mut sum = acc.reduce_sum();
-    for &v in x.chunks_exact(16).remainder() {
+    for &v in remainder {
         sum += v.abs();
     }
     sum
@@ -190,12 +191,13 @@ pub fn asum_f32(x: &[f32]) -> f32 {
 #[cfg(target_arch = "x86_64")]
 #[target_feature(enable = "avx512f")]
 pub fn asum_f64(x: &[f64]) -> f64 {
+    let (chunks, remainder) = x.as_chunks::<8>();
     let mut acc = F64x8::splat(0.0);
-    for chunk in x.chunks_exact(8) {
+    for chunk in chunks {
         acc += F64x8::from_slice(chunk).abs();
     }
     let mut sum = acc.reduce_sum();
-    for &v in x.chunks_exact(8).remainder() {
+    for &v in remainder {
         sum += v.abs();
     }
     sum

src/lib.rs

@@ -19,7 +19,6 @@
     clippy::deref_addrof,
     clippy::manual_map, // is not an error
     clippy::while_let_on_iterator, // is not an error
-    clippy::from_iter_instead_of_collect, // using from_iter is good style
     clippy::incompatible_msrv, // false positive PointerExt::offset
 )]
 #![doc(test(attr(deny(warnings))))]

src/simd_ops.rs

@@ -609,7 +609,12 @@ pub fn bf16_tile_gemm_16x16(a_bf16: &[u16], b_bf16: &[u16], c: &mut [f32], k: us
                 *slot = b_f32[kk * 16 + j];
             }
             let mut acc = F32x16::splat(0.0);
-            for (ra, rb) in a_row.chunks_exact(16).zip(col.chunks_exact(16)) {
+            for (ra, rb) in a_row
+                .as_chunks::<16>()
+                .0
+                .iter()
+                .zip(col.as_chunks::<16>().0)
+            {
                 acc = F32x16::from_slice(ra).mul_add(F32x16::from_slice(rb), acc);
             }
             c[i * 16 + j] += acc.reduce_sum();