build: pin rust 1.98.1 so macOS 27 loads our stripped dylibs

.github/actions/rust-cache/action.yml

@@ -28,7 +28,7 @@ runs:
         # whatever the runner image ships: the compiler these jobs build with
         # exists only inside `nix develop`. The `toolchain` input is no help
         # either, since it names a rustup toolchain and probes
-        # `rustc +<name> -vV`, and nothing installs 1.95.0 through rustup.
+        # `rustc +<name> -vV`, and nothing installs that channel through rustup.
         #
         # flake.lock pins that compiler, so hashing the flake identifies it more
         # precisely than `rustc -vV` would, and rolls the cache when the dev

Cargo.toml

@@ -90,9 +90,9 @@ ignored = ["getrandom"]
 # it to 1.95 (sysinfo 0.39), and moq-cli does too because it depends on that
 # library. Those crates are applications; the point of the per-crate override
 # is to keep the bump off the libraries others actually build on. The nix flake
-# / rust-toolchain.toml pin the build toolchain to 1.95 (so the whole workspace
-# including the relay compiles) rather than latest stable, which keeps the
-# relay's ceiling from creeping up unnoticed.
+# / rust-toolchain.toml pin the build toolchain to a fixed version rather than
+# latest stable, which keeps the relay's ceiling from creeping up unnoticed.
+# That pin sits above every MSRV here; rust-toolchain.toml says why.
 rust-version = "1.91"
 
 [workspace.dependencies]

flake.nix

@@ -59,10 +59,12 @@
 
         # Pinned build toolchain (not latest stable) so `nix develop` and CI
         # compile against a fixed rustc and the relay's MSRV can't creep up
-        # unnoticed. Set to moq-relay's 1.95 (the highest crate MSRV in the
-        # workspace) so the whole workspace, including the relay, builds; the
-        # library crates declare a lower 1.91 floor (Cargo.toml rust-version).
-        rust-toolchain = pkgs.rust-bin.stable."1.95.0".default.override {
+        # unnoticed. The floor is 1.98, not the 1.95 relay MSRV: earlier rustc
+        # strips Mach-O debuginfo with an llvm-objcopy that leaves the LINKEDIT
+        # string pool 4-byte aligned, which macOS 27's dyld refuses to load, so
+        # release-profile proc macros and cdylibs are a coin flip there. The
+        # crates still declare their own lower floors (Cargo.toml rust-version).
+        rust-toolchain = pkgs.rust-bin.stable."1.98.1".default.override {
           extensions = [
             "rust-src"
             "rust-analyzer"

nix/overlay.nix

@@ -2,13 +2,12 @@
 { crane }:
 final: prev:
 let
-  # Pin crane to the workspace MSRV (Cargo.toml rust-version /
-  # rust-toolchain.toml) so `nix build` uses the same toolchain as
-  # `nix develop` and release artifacts build with the version CI verifies.
-  # Without an explicit toolchain, crane falls back to `final.rustc`/
-  # `final.cargo`, which nixpkgs resolves to its own default Rust.
+  # Pin crane to the same build toolchain as rust-toolchain.toml / flake.nix so
+  # `nix build` uses what `nix develop` does and release artifacts build with
+  # the version CI verifies. Without an explicit toolchain, crane falls back to
+  # `final.rustc`/`final.cargo`, which nixpkgs resolves to its own default Rust.
   #
-  rustToolchain = final.rust-bin.stable."1.95.0".default;
+  rustToolchain = final.rust-bin.stable."1.98.1".default;
   craneLib = (crane.mkLib final).overrideToolchain rustToolchain;
 
   # Helper function to get crate info from Cargo.toml

rs/kio/src/waiter.rs

@@ -808,6 +808,10 @@ mod tests {
 	#[test]
 	fn park_retires_a_waiter_for_another_task() {
 		struct Nop;
+		// Not `Waker::noop()`, which clippy suggests: that is a singleton, so the two
+		// wakers below would name the same task and the assertion would pass without
+		// testing anything. What this needs is two wakers that do nothing and differ.
+		#[expect(clippy::manual_noop_waker, reason = "the two wakers must not be identical")]
 		impl std::task::Wake for Nop {
 			fn wake(self: Arc<Self>) {}
 		}

rs/moq-relay/src/web.rs

@@ -762,6 +762,8 @@ async fn admit_http(
 }
 
 /// Serve the announced broadcasts for a given prefix.
+// The `Err` is axum's own `ErrorResponse`, so there is nothing here to box.
+#[expect(clippy::result_large_err, reason = "the error type is axum's, not ours")]
 async fn serve_announced(
 	path: Option<Path<String>>,
 	Query(query): Query<AuthQuery>,
@@ -799,6 +801,8 @@ async fn serve_announced(
 }
 
 /// Serve the given group for a given track
+// The `Err` is axum's own `ErrorResponse`, so there is nothing here to box.
+#[expect(clippy::result_large_err, reason = "the error type is axum's, not ours")]
 async fn serve_fetch(
 	Path(path): Path<String>,
 	Query(params): Query<FetchParams>,

rs/moq-relay/src/websocket.rs

@@ -19,6 +19,8 @@ use crate::{auth, web::MtlsPeer, web::WebState, web::landing_response};
 
 // One axum extractor per fact the upgrade needs; there is no struct to fold them into.
 #[allow(clippy::too_many_arguments)]
+// The `Err` is axum's own `ErrorResponse`, so there is nothing here to box.
+#[expect(clippy::result_large_err, reason = "the error type is axum's, not ours")]
 pub(crate) async fn serve_ws(
 	ws: Result<WebSocketUpgrade, WebSocketUpgradeRejection>,
 	OriginalUri(uri): OriginalUri,

rust-toolchain.toml

@@ -1,6 +1,9 @@
 [toolchain]
-# Pinned to the build toolchain: moq-relay's 1.95 (the highest crate MSRV), so
-# the whole workspace compiles. NOT the 1.91 workspace library floor in
-# Cargo.toml. Keep in sync with flake.nix / nix/overlay.nix.
-channel = "1.95.0"
+# Pinned to the build toolchain, NOT the 1.91 workspace library floor or the
+# 1.95 relay MSRV in Cargo.toml. It has to be at least 1.98: below that, rustc
+# strips Mach-O debuginfo with an llvm-objcopy that leaves the LINKEDIT string
+# pool 4-byte aligned, and macOS 27's dyld refuses to load such an image. That
+# makes every release-profile proc macro and cdylib (moq-ffi, moq-gst) a coin
+# flip there. Keep in sync with flake.nix / nix/overlay.nix.
+channel = "1.98.1"
 components = ["rustfmt", "clippy"]