fix a bunch of lints

Flake lock file updates:

• Updated input 'fenix':
    'github:nix-community/fenix/64407ddb1932af06ed5cd711f6a2ed946b2548b9' (2026-03-10)
  → 'github:nix-community/fenix/4cd28929c68cae521589bc21958d3793904ed1e2' (2026-03-22)
• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/608d0cadfed240589a7eea422407a547ad626a14' (2026-03-08)
  → 'github:NixOS/nixpkgs/9cf7092bdd603554bd8b63c216e8943cf9b12512' (2026-03-18)

.cargo/config.toml

@@ -0,0 +1,10 @@
+# SPDX-FileCopyrightText: 2026 Qyriad <qyriad@qyriad.me>
+#
+# SPDX-License-Identifier: EUPL-1.1
+# vim: tabstop=2 shiftwidth=0 noexpandtab
+
+[build]
+rustflags = [
+	"-C", "force-frame-pointers=yes",
+	"-C", "force-unwind-tables=yes",
+]

Cargo.toml

@@ -47,3 +47,19 @@ tap = "1.0.1"
 tracing = { version = "0.1.44", features = ["attributes"] }
 tracing-human-layer = "0.2.1"
 tracing-subscriber = { version = "0.3.22", default-features = false, features = ["std", "env-filter", "fmt", "ansi", "registry", "parking_lot"] }
+
+[profile.dev]
+opt-level = 1
+lto = "thin"
+
+[profile.release]
+debug = true
+debug-assertions = true
+lto = true
+
+[profile.dev.package."*"]
+opt-level = 1
+
+[profile.release.package."*"]
+debug = true
+debug-assertions = true

default.nix

@@ -9,7 +9,11 @@
   in import src { inherit pkgs; },
 }: let
   inherit (qpkgs) lib;
-  dynix = qpkgs.callPackage ./package.nix { }
+  dynix = (qpkgs.callPackage ./package.nix { })
+    .overrideAttrs (final: prev: {
+      dynixCommand = qpkgs.stdlib.mkStdenvPretty prev.dynixCommand;
+      dynixModules = qpkgs.stdlib.mkStdenvPretty prev.dynixModules;
+    })
   |> qpkgs.stdlib.mkStdenvPretty;
   byStdenv = lib.mapAttrs (stdenvName: stdenv: let
     withStdenv = dynix.override { clangStdenv = stdenv; };

flake.lock

@@ -3,11 +3,11 @@
     "fenix": {
       "flake": false,
       "locked": {
-        "lastModified": 1773126504,
+        "lastModified": 1774163246,
-        "narHash": "sha256-/iXlg2V5UMlgCmyRHkPHjlD6NdMfFOnwFMvH7REigD4=",
+        "narHash": "sha256-gzlqyLjP44LWraUd3Zn4xrQKOtK+zcBJ77pnsSUsxcM=",
         "owner": "nix-community",
         "repo": "fenix",
-        "rev": "64407ddb1932af06ed5cd711f6a2ed946b2548b9",
+        "rev": "4cd28929c68cae521589bc21958d3793904ed1e2",
         "type": "github"
       },
       "original": {
@@ -37,11 +37,11 @@
     "nixpkgs": {
       "flake": false,
       "locked": {
-        "lastModified": 1772956932,
+        "lastModified": 1773840656,
-        "narHash": "sha256-M0yS4AafhKxPPmOHGqIV0iKxgNO8bHDWdl1kOwGBwRY=",
+        "narHash": "sha256-9tpvMGFteZnd3gRQZFlRCohVpqooygFuy9yjuyRL2C0=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "608d0cadfed240589a7eea422407a547ad626a14",
+        "rev": "9cf7092bdd603554bd8b63c216e8943cf9b12512",
         "type": "github"
       },
       "original": {

package.nix

@@ -7,14 +7,23 @@
   clangStdenv,
   callPackage,
   linkFarm,
+  llvmPackages,
   rustHooks,
   rustPackages,
   versionCheckHook,
+  wrapBintoolsWith,
 }: lib.callWith' rustPackages ({
   rustPlatform,
   cargo,
 }: let
-  stdenv = clangStdenv;
+  # Use LLD for faster link times.
+  stdenv = clangStdenv.override {
+    cc = clangStdenv.cc.override {
+      bintools = wrapBintoolsWith {
+        bintools = llvmPackages.bintools;
+      };
+    };
+  };
   cargoToml = lib.importTOML ./Cargo.toml;
   cargoPackage = cargoToml.package;
 in stdenv.mkDerivation (finalAttrs: let

shell.nix

@@ -21,7 +21,7 @@
   inherit (pkgs) lib;
 
   mkDevShell = dynix: qpkgs.callPackage dynix.mkDevShell { inherit fenixToolchain; };
-  devShell = mkDevShell dynix;
+  devShell = mkDevShell dynix |> qpkgs.stdlib.mkStdenvPretty;
 
   byStdenv = lib.mapAttrs (lib.const mkDevShell) dynix.byStdenv;
 

src/daemon.rs

@@ -1,5 +1,5 @@
 use std::{
-    env, io, mem,
+    env, io,
     ops::Deref,
     os::fd::{AsFd, BorrowedFd, IntoRawFd, OwnedFd, RawFd},
     sync::{
@@ -26,7 +26,7 @@ use crate::{
 
 use crate::{OwnedFdWithFlags, TokenFd};
 
-pub static UID: LazyLock<Uid> = LazyLock::new(|| rustix::process::getuid());
+pub static UID: LazyLock<Uid> = LazyLock::new(rustix::process::getuid);
 
 pub static USER_SOCKET_DIR: LazyLock<&'static Path> = LazyLock::new(|| {
     let dir: Box<Path> = env::var_os("XDG_RUNTIME_DIR")
@@ -52,19 +52,23 @@ pub enum ConvenientAttrPath {
 }
 
 impl ConvenientAttrPath {
+    /// Not currently used, but here for completeness.
+    #[expect(dead_code)]
     pub fn clone_from_dotted(s: &str) -> Self {
         Self::Dotted(Box::from(s))
     }
 
+    /// Not currently used, but here for completeness.
+    #[expect(dead_code)]
     pub fn clone_from_split(s: &[&str]) -> Self {
-        Self::from_str_iter(s.into_iter().map(Deref::deref))
+        Self::from_str_iter(s.iter().map(Deref::deref))
     }
 
     pub fn from_str_iter<'i, I>(iter: I) -> Self
     where
         I: Iterator<Item = &'i str>,
     {
-        let boxed = iter.map(|s| Box::from(s));
+        let boxed = iter.map(Box::from);
         Self::Split(Box::from_iter(boxed))
     }
 
@@ -135,9 +139,6 @@ pub struct Daemon {
 
     // Bijective mapping of [`mio::Token`]s to [`RawFd`]s.
     tokfd: BiHashMap<TokenFd>,
-
-    cmd_buffer: Vec<u8>,
-    next_timeout: Option<Duration>,
 }
 
 /// `tokfd` handling.
@@ -222,6 +223,8 @@ impl Daemon {
             .copied()
     }
 
+    /// Not currently used, but here for completeness.
+    #[expect(dead_code)]
     fn token_for_fd(&self, fd: RawFd) -> Option<Token> {
         self.tokfd
             .get2(&fd)
@@ -255,10 +258,10 @@ impl Daemon {
 
         debug!("opened daemon to {:?} file descriptor {fd:?}", name);
 
-        let path = match &name {
+        let path = name
-            Some(name) => Some(PathBuf::from(name).into_boxed_path()),
+            .as_ref()
-            None => None,
+            .map(PathBuf::from)
-        };
+            .map(PathBuf::into_boxed_path);
 
         Self {
             config_path,
@@ -267,8 +270,6 @@ impl Daemon {
             poller,
             fd_info,
             tokfd: Default::default(),
-            cmd_buffer: Vec::with_capacity(1024),
-            next_timeout: TIMEOUT_NEVER,
         }
     }
 
@@ -345,16 +346,12 @@ impl Daemon {
 /// Private helpers.
 impl Daemon {
     fn read_cmd(&mut self, fd: &BorrowedFd) -> Result<(), IoError> {
-        if self.cmd_buffer.len() == self.cmd_buffer.capacity() {
+        // FIXME: don't use a new allocation every time.
-            self.cmd_buffer.reserve(1024);
+        let mut cmd_buffer: Vec<u8> = Vec::with_capacity(1024);
-        }
 
-        let _count = rustix::io::read(fd, spare_capacity(&mut self.cmd_buffer))
+        let _count = rustix::io::read(fd, spare_capacity(&mut cmd_buffer))
             .tap_err(|e| error!("read() on daemon fd {fd:?} failed: {e}"))?;
 
-        // So that the loop doesn't borrow from `self`.
-        let mut cmd_buffer = mem::take(&mut self.cmd_buffer);
-
         // The buffer might have existing data from the last read.
         let deserializer = serde_json::Deserializer::from_slice(&cmd_buffer);
         let stream: StreamDeserializer<_, DaemonCmd> = deserializer.into_iter();
@@ -362,16 +359,13 @@ impl Daemon {
             let cmd = match cmd {
                 Ok(cmd) => cmd,
                 Err(e) if e.is_eof() => {
-                    self.next_timeout = Some(Duration::from_secs(4));
+                    warn!("Got EOF before a valid command");
-                    warn!("Didn't get a valid daemon command; giving the other side 4 seconds...");
+                    debug!("command buffer was: {:?}", cmd_buffer.as_bstr());
-                    let _ = mem::replace(&mut self.cmd_buffer, cmd_buffer);
                     return Ok(());
                 },
                 Err(e) => {
                     warn!("error deserializing command: {e}");
                     debug!("command buffer was: {:?}", cmd_buffer.as_bstr());
-                    cmd_buffer.clear();
-                    let _ = mem::replace(&mut self.cmd_buffer, cmd_buffer);
                     // Don't propagate the error unless we have too many.
                     self.fd_error_push(fd.as_raw_fd(), e.into()).tap_err(|e| {
                         error!("Accumulated too many errors for daemon fd {fd:?}: {e}")
@@ -385,9 +379,6 @@ impl Daemon {
             self.dispatch_cmd(cmd).unwrap_or_else(|e| todo!("{e}"));
         }
 
-        cmd_buffer.clear();
-        let _ = mem::replace(&mut self.cmd_buffer, cmd_buffer);
-
         Ok(())
     }
 
@@ -469,25 +460,19 @@ impl Daemon {
                 }
             }
 
-            if let Some(timeout) = self.next_timeout {
+            match self.poller.poll(&mut events, TIMEOUT_NEVER) {
-                debug!(
-                    "epoll_wait() with a timeout: {}",
-                    humantime::format_duration(timeout),
-                );
-            }
-
-            match self.poller.poll(&mut events, self.next_timeout.take()) {
                 Ok(_) => {
                     trace!(
                         "mio::Poller::poll() got events: {:?}",
                         events.iter().size_hint().0,
                     );
                     if events.is_empty() {
-                        warn!("timeout expired");
+                        unreachable!(
-                        self.cmd_buffer.clear();
+                            "epoll_wait() with a \"forever\" timeout should never give empty events",
-                    } else {
+                        );
-                        let _ = self.fd_error_pop(self.poller.as_raw_fd());
                     }
+
+                    let _ = self.fd_error_pop(self.poller.as_raw_fd());
                 },
                 Err(e) if e.kind() == IoErrorKind::Interrupted => {
                     // EINTR is silly.

src/daemon_io.rs

@@ -130,7 +130,7 @@ impl From<OwnedFd> for OwnedFdWithFlags {
 
 impl Read for &OwnedFdWithFlags {
     fn read(&mut self, buf: &mut [u8]) -> Result<usize, IoError> {
-        debug_assert!(buf.len() > 0);
+        debug_assert!(!buf.is_empty());
         loop {
             buf.fill(0);
             match rustix::io::read(self.as_ref_owned(), &mut *buf) {

src/daemon_tokfd.rs

@@ -52,7 +52,7 @@ impl FdInfo {
 
         match Self::guess_name(self.fd) {
             Ok(name) => {
-                let prev = self.name.set(Box::from(name));
+                let prev = self.name.set(name);
                 debug_assert_eq!(prev, Ok(()));
             },
             Err(e) => {
@@ -105,13 +105,14 @@ impl<'a> Display for FdInfoDisplay<'a> {
 }
 
 #[derive(Copy)]
-#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
 #[non_exhaustive]
 pub enum FdKind {
     File,
     Socket,
     SockStream,
     Poller,
+    #[default]
     Unknown,
 }
 
@@ -128,12 +129,6 @@ impl FdKind {
     }
 }
 
-impl Default for FdKind {
-    fn default() -> FdKind {
-        FdKind::Unknown
-    }
-}
-
 #[derive(Copy)]
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct TokenFd {

src/main.rs

@@ -14,7 +14,7 @@ use tracing_subscriber::{EnvFilter, layer::SubscriberExt};
 
 fn main_wrapped() -> Result<(), Box<dyn StdError + Send + Sync + 'static>> {
     // Default RUST_LOG to warn if it's not specified.
-    if let None = env::var_os("RUST_LOG") {
+    if env::var_os("RUST_LOG").is_none() {
         unsafe {
             env::set_var("RUST_LOG", "warn");
         }

src/nixcmd.rs

@@ -5,27 +5,27 @@
 #[allow(unused_imports)]
 use crate::prelude::*;
 
-#[derive(Debug, Clone, PartialEq, Hash)]
+//#[derive(Debug, Clone, PartialEq, Hash)]
-pub(crate) struct NixEvalExpr<E, A> {
+//pub(crate) struct NixEvalExpr<E, A> {
-    pub(crate) expr: E,
+//    pub(crate) expr: E,
-    pub(crate) attrpath: A,
+//    pub(crate) attrpath: A,
-}
+//}
-
+//
-impl<E, A> NixEvalExpr<E, A>
+//impl<E, A> NixEvalExpr<E, A>
-where
+//where
-    E: AsRef<OsStr>,
+//    E: AsRef<OsStr>,
-    A: AsRef<OsStr>,
+//    A: AsRef<OsStr>,
-{
+//{
-    pub(crate) fn into_command(self) -> Command {
+//    pub(crate) fn into_command(self) -> Command {
-        let mut cmd = Command::new("nix-instantiate");
+//        let mut cmd = Command::new("nix-instantiate");
-        cmd.arg("--eval")
+//        cmd.arg("--eval")
-            .arg("--json")
+//            .arg("--json")
-            .arg("--strict")
+//            .arg("--strict")
-            .arg("--expr")
+//            .arg("--expr")
-            .arg(self.expr)
+//            .arg(self.expr)
-            .arg("-A")
+//            .arg("-A")
-            .arg(self.attrpath);
+//            .arg(self.attrpath);
-
+//
-        cmd
+//        cmd
-    }
+//    }
-}
+//}