Upgrade rustc to nightly-2026-10-04

.devcontainer/rust/devcontainer-feature.json

@@ -5,7 +5,7 @@
   "dependsOn": {
     "ghcr.io/devcontainers/features/rust:1": {
       // this should match the `rust-toolchain.toml`
-      "version": "nightly-2026-08-20",
+      "version": "nightly-2026-10-06",
       "profile": "minimal",
       "components": "rustfmt,clippy,rust-analyzer,miri"
     }

Cargo.toml

@@ -31,6 +31,10 @@ unexpected_cfgs = { level = "warn", check-cfg = [
   'cfg(codspeed)',
 ] }
 
+[workspace.lints.cargo]
+# These are generally useful, but there are a lot of false positives when running commands scoped to individual workspace members.
+unused_workspace_dependencies = "allow"
+
 [profile.dev]
 # https://kobzol.github.io/rust/rustc/2025/05/20/disable-debuginfo-to-improve-rust-compile-times.html
 debug = "line-tables-only"
@@ -271,7 +275,6 @@ crossbeam-utils = "0.8"
 dashmap = "7.0.0-rc2"
 data-encoding = "2.3.3"
 dhat = { version = "0.3.2" }
-dunce = "1.0.3"
 either = "1.15.0"
 erased-serde = "0.4.5"
 fixedbitset = "0.5.7"
@@ -308,7 +311,7 @@ napi = { version = "3.10.0", default-features = false, features = [
   "napi5",
 ] }
 napi-derive = "3.5.8"
-napi-build = "2.3.2"
+napi-build = "2.6.0"
 nohash-hasher = "0.2.0"
 notify = "9.0.0-rc.5"
 owo-colors = "4.2.2"
@@ -333,7 +336,6 @@ roaring = "0.11.4"
 rstest = "0.16.0"
 rustc-hash = "2.1.1"
 scattered-collect = "0.10.0"
-semver = "1.0.16"
 serde = { version = "1.0.228", features = ["derive"] }
 serde_json = "1.0.149"
 serde_path_to_error = "0.1.20"

rust-toolchain.toml

@@ -1,6 +1,6 @@
 # if you update this, also update `.devcontainer/rust/devcontainer-feature.json`
 # if you move the file, also update any turbo.json inputs that references it.
 [toolchain]
-channel = "nightly-2026-08-20"
+channel = "nightly-2026-10-06"
 components = ["rustfmt", "clippy", "rust-analyzer", "miri"]
 profile = "minimal"

turbopack/crates/turbo-persistence/src/db.rs

@@ -247,7 +247,9 @@ fn commit_current(path: &Path, seq: u32) -> Result<()> {
     // Skipped on Windows: `sync_data` on a directory handle fails with ERROR_ACCESS_DENIED (the
     // handle `File::open` returns for a directory has no write access).Apparently metadata changes
     // are always atomic on windows so this is simply unneeded.
-    #[cfg(not(windows))]
+    //
+    // Miri supports opening directories, but not syncing directory descriptors.
+    #[cfg(not(any(windows, miri)))]
     File::open(path)
         .and_then(|dir| dir.sync_data())
         .context("Failed to sync database directory after updating CURRENT")?;

turbopack/crates/turbo-tasks-macros-tests/tests/function/fail_operation_method_self_type.stderr

@@ -24,7 +24,6 @@ note: required by a bound in `turbo_tasks::macro_helpers::into_task_fn_with_this
   --> $WORKSPACE/turbopack/crates/turbo-tasks/src/task/function.rs
    |
    | pub const fn into_task_fn_with_this<
-   |              ---------------------- required by a bound in this function
 ...
    |     F: TaskFnInputFunctionWithThis<Mode, This, Inputs>,
    |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `into_task_fn_with_this`

turbopack/crates/turbo-tasks-malloc/Cargo.toml

@@ -13,6 +13,9 @@ bench = false
 name = "allocation"
 harness = false
 
+[lints]
+workspace = true
+
 [dependencies]
 
 [dev-dependencies]

turbopack/crates/turbo-tasks/src/lib.rs

@@ -6,7 +6,6 @@
 #![feature(arbitrary_self_types)]
 #![feature(arbitrary_self_types_pointers)]
 #![feature(ptr_metadata)]
-#![feature(exclusive_wrapper)]
 #![feature(sync_unsafe_cell)]
 #![feature(async_fn_traits)]
 #![feature(impl_trait_in_assoc_type)]

turbopack/crates/turbopack-trace-server/Cargo.toml

@@ -10,6 +10,9 @@ autobenches = false
 default = ["custom_allocator"]
 custom_allocator = ["turbo-tasks-malloc/custom_allocator"]
 
+[lints]
+workspace = true
+
 [[bin]]
 name = "turbo-trace-server"
 path = "src/main.rs"

turbopack/crates/turbopack-trace-utils/Cargo.toml

@@ -9,7 +9,8 @@ autobenches = false
 [lib]
 bench = false
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+[lints]
+workspace = true
 
 [dependencies]
 anyhow = { workspace = true }