Lockless LintStore

Cargo.lock

@@ -3483,6 +3483,7 @@ dependencies = [
  "rustc_data_structures",
  "rustc_errors",
  "rustc_interface",
+ "rustc_lint",
  "rustc_metadata",
  "rustc_mir",
  "rustc_plugin",

src/librustc/lint/context.rs

@@ -35,7 +35,7 @@ use crate::util::common::time;
 use errors::DiagnosticBuilder;
 use std::slice;
 use std::default::Default as StdDefault;
-use rustc_data_structures::sync::{ReadGuard, ParallelIterator, join, par_iter};
+use rustc_data_structures::sync::{ParallelIterator, join, par_iter};
 use rustc_serialize::{Decoder, Decodable, Encoder, Encodable};
 use syntax::ast;
 use syntax::util::lev_distance::find_best_match_for_name;
@@ -452,7 +452,7 @@ pub struct LateContext<'a, 'tcx> {
  pub access_levels: &'a AccessLevels,
 
  /// The store of registered lints and the lint levels.
- lint_store: ReadGuard<'a, LintStore>,
+ lint_store: &'tcx LintStore,
 
  last_node_with_lint_attrs: hir::HirId,
 
@@ -1320,7 +1320,7 @@ fn late_lint_mod_pass<'tcx, T: for<'a> LateLintPass<'a, 'tcx>>(
  tables: &ty::TypeckTables::empty(None),
  param_env: ty::ParamEnv::empty(),
  access_levels,
- lint_store: tcx.sess.lint_store.borrow(),
+ lint_store: &tcx.lint_store,
  last_node_with_lint_attrs: tcx.hir().as_local_hir_id(module_def_id).unwrap(),
  generics: None,
  only_module: true,
@@ -1352,7 +1352,7 @@ pub fn late_lint_mod<'tcx, T: for<'a> LateLintPass<'a, 'tcx>>(
 
  late_lint_mod_pass(tcx, module_def_id, builtin_lints);
 
- let mut passes: Vec<_> = tcx.sess.lint_store.borrow().late_module_passes
+ let mut passes: Vec<_> = tcx.lint_store.late_module_passes
  .iter().map(|pass| (pass)()).collect();
 
  if !passes.is_empty() {
@@ -1370,7 +1370,7 @@ fn late_lint_pass_crate<'tcx, T: for<'a> LateLintPass<'a, 'tcx>>(tcx: TyCtxt<'tc
  tables: &ty::TypeckTables::empty(None),
  param_env: ty::ParamEnv::empty(),
  access_levels,
- lint_store: tcx.sess.lint_store.borrow(),
+ lint_store: &tcx.lint_store,
  last_node_with_lint_attrs: hir::CRATE_HIR_ID,
  generics: None,
  only_module: false,
@@ -1394,7 +1394,7 @@ fn late_lint_pass_crate<'tcx, T: for<'a> LateLintPass<'a, 'tcx>>(tcx: TyCtxt<'tc
 }
 
 fn late_lint_crate<'tcx, T: for<'a> LateLintPass<'a, 'tcx>>(tcx: TyCtxt<'tcx>, builtin_lints: T) {
- let mut passes = tcx.sess.lint_store.borrow()
+ let mut passes = tcx.lint_store
  .late_passes.iter().map(|p| (p)()).collect::<Vec<_>>();
 
  if !tcx.sess.opts.debugging_opts.no_interleave_lints {
@@ -1410,7 +1410,7 @@ fn late_lint_crate<'tcx, T: for<'a> LateLintPass<'a, 'tcx>>(tcx: TyCtxt<'tcx>, b
  });
  }
 
- let mut passes: Vec<_> = tcx.sess.lint_store.borrow().late_module_passes
+ let mut passes: Vec<_> = tcx.lint_store.late_module_passes
  .iter().map(|pass| (pass)()).collect();
 
  for pass in &mut passes {
@@ -1571,7 +1571,7 @@ impl Decodable for LintId {
  fn decode<D: Decoder>(d: &mut D) -> Result<LintId, D::Error> {
  let s = d.read_str()?;
  ty::tls::with(|tcx| {
- match tcx.sess.lint_store.borrow().find_lints(&s) {
+ match tcx.lint_store.find_lints(&s) {
  Ok(ids) => {
  if ids.len() != 0 {
  panic!("invalid lint-id `{}`", s);

src/librustc/lint/mod.rs

@@ -777,11 +777,11 @@ pub fn maybe_lint_level_root(tcx: TyCtxt<'_>, id: hir::HirId) -> bool {
 
 fn lint_levels(tcx: TyCtxt<'_>, cnum: CrateNum) -> &LintLevelMap {
  assert_eq!(cnum, LOCAL_CRATE);
- let store = tcx.sess.lint_store.borrow();
+ let store = &tcx.lint_store;
  let mut builder = LintLevelMapBuilder {
  levels: LintLevelSets::builder(tcx.sess, &store),
  tcx: tcx,
- store: &*store,
+ store: store,
  };
  let krate = tcx.hir().krate();
 

src/librustc/session/mod.rs

@@ -14,7 +14,7 @@ use crate::util::common::{duration_to_secs_str, ErrorReported};
 
 use rustc_data_structures::base_n;
 use rustc_data_structures::sync::{
- self, Lrc, Lock, OneThread, Once, RwLock, AtomicU64, AtomicUsize, Ordering,
+ self, Lrc, Lock, OneThread, Once, AtomicU64, AtomicUsize, Ordering,
  Ordering::SeqCst,
 };
 
@@ -77,9 +77,11 @@ pub struct Session {
  /// if the value stored here has been affected by path remapping.
  pub working_dir: (PathBuf, bool),
 
- // FIXME: `lint_store` and `buffered_lints` are not thread-safe,
- // but are only used in a single thread.
- pub lint_store: RwLock<lint::LintStore>,
+ /// This is intended to be used from a single thread.
+ ///
+ /// FIXME: there was a previous comment about this not being thread safe,
+ /// but it's not clear how or why that's the case. The LintBuffer itself is certainly thread
+ /// safe at least from a "Rust safety" standpoint.
  pub buffered_lints: Lock<Option<lint::LintBuffer>>,
 
  /// Set of `(DiagnosticId, Option<Span>, message)` tuples tracking
@@ -1213,7 +1215,6 @@ fn build_session_(
  sysroot,
  local_crate_source_file,
  working_dir,
- lint_store: RwLock::new(lint::LintStore::new()),
  buffered_lints: Lock::new(Some(Default::default())),
  one_time_diagnostics: Default::default(),
  plugin_llvm_passes: OneThread::new(RefCell::new(Vec::new())),

src/librustc/ty/context.rs

@@ -1035,6 +1035,8 @@ pub struct GlobalCtxt<'tcx> {
 
  pub sess: &'tcx Session,
 
+ pub lint_store: Lrc<lint::LintStore>,
+
  pub dep_graph: DepGraph,
 
  pub prof: SelfProfilerRef,
@@ -1199,6 +1201,7 @@ impl<'tcx> TyCtxt<'tcx> {
  /// reference to the context, to allow formatting values that need it.
  pub fn create_global_ctxt(
  s: &'tcx Session,
+ lint_store: Lrc<lint::LintStore>,
  cstore: &'tcx CrateStoreDyn,
  local_providers: ty::query::Providers<'tcx>,
  extern_providers: ty::query::Providers<'tcx>,
@@ -1268,6 +1271,7 @@ impl<'tcx> TyCtxt<'tcx> {
 
  GlobalCtxt {
  sess: s,
+ lint_store,
  cstore,
  arena: WorkerLocal::new(|_| Arena::default()),
  interners,

src/librustc_driver/Cargo.toml

@@ -16,6 +16,7 @@ log = "0.4"
 env_logger = { version = "0.7", default-features = false }
 rustc = { path = "../librustc" }
 rustc_target = { path = "../librustc_target" }
+rustc_lint = { path = "../librustc_lint" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 errors = { path = "../librustc_errors", package = "rustc_errors" }
 rustc_metadata = { path = "../librustc_metadata" }

src/librustc_driver/lib.rs

@@ -202,9 +202,13 @@ pub fn run_compiler(
  interface::run_compiler(config, |compiler| {
  let sopts = &compiler.session().opts;
  if sopts.describe_lints {
+ let lint_store = rustc_lint::new_lint_store(
+ sopts.debugging_opts.no_interleave_lints,
+ compiler.session().unstable_options(),
+ );
  describe_lints(
  compiler.session(),
- &*compiler.session().lint_store.borrow(),
+ &lint_store,
  false
  );
  return;
@@ -321,12 +325,14 @@ pub fn run_compiler(
  return sess.compile_status();
  }
 
- compiler.register_plugins()?;
+ {
+ let (_, _, lint_store) = &*compiler.register_plugins()?.peek();
 
- // Lint plugins are registered; now we can process command line flags.
- if sess.opts.describe_lints {
- describe_lints(&sess, &sess.lint_store.borrow(), true);
- return sess.compile_status();
+ // Lint plugins are registered; now we can process command line flags.
+ if sess.opts.describe_lints {
+ describe_lints(&sess, &lint_store, true);
+ return sess.compile_status();
+ }
  }
 
  compiler.expansion()?;

src/librustc_interface/passes.rs

@@ -117,6 +117,7 @@ declare_box_region_type!(
 /// Returns `None` if we're aborting after handling -W help.
 pub fn configure_and_expand(
  sess: Lrc<Session>,
+ lint_store: Lrc<lint::LintStore>,
  cstore: Lrc<CStore>,
  krate: ast::Crate,
  crate_name: &str,
@@ -134,6 +135,7 @@ pub fn configure_and_expand(
  let resolver_arenas = Resolver::arenas();
  let res = configure_and_expand_inner(
  sess,
+ &lint_store,
  &*cstore,
  krate,
  &crate_name,
@@ -227,7 +229,7 @@ pub fn register_plugins<'a>(
  cstore: &'a CStore,
  mut krate: ast::Crate,
  crate_name: &str,
-) -> Result<(ast::Crate, PluginInfo)> {
+) -> Result<(ast::Crate, PluginInfo, Lrc<lint::LintStore>)> {
  krate = time(sess, "attributes injection", || {
  syntax_ext::cmdline_attrs::inject(
  krate, &sess.parse_sess, &sess.opts.debugging_opts.crate_attr
@@ -278,7 +280,12 @@ pub fn register_plugins<'a>(
  )
  });
 
- let mut registry = Registry::new(sess, krate.span);
+ let mut lint_store = rustc_lint::new_lint_store(
+ sess.opts.debugging_opts.no_interleave_lints,
+ sess.unstable_options(),
+ );
+
+ let mut registry = Registry::new(sess, &mut lint_store, krate.span);
 
  time(sess, "plugin registration", || {
  for registrar in registrars {
@@ -289,36 +296,20 @@ pub fn register_plugins<'a>(
 
  let Registry {
  syntax_exts,
- early_lint_passes,
- late_lint_passes,
- lints,
- lint_groups,
  llvm_passes,
  attributes,
  ..
  } = registry;
 
- let mut ls = sess.lint_store.borrow_mut();
- ls.register_lints(&lints);
- for pass in early_lint_passes {
- ls.register_early_pass(pass);
- }
- for pass in late_lint_passes {
- ls.register_late_pass(pass);
- }
-
- for (name, (to, deprecated_name)) in lint_groups {
- ls.register_group(true, name, deprecated_name, to);
- }
-
  *sess.plugin_llvm_passes.borrow_mut() = llvm_passes;
  *sess.plugin_attributes.borrow_mut() = attributes;
 
- Ok((krate, PluginInfo { syntax_exts }))
+ Ok((krate, PluginInfo { syntax_exts }, Lrc::new(lint_store)))
 }
 
 fn configure_and_expand_inner<'a>(
  sess: &'a Session,
+ lint_store: &'a lint::LintStore,
  cstore: &'a CStore,
  mut krate: ast::Crate,
  crate_name: &str,
@@ -329,7 +320,7 @@ fn configure_and_expand_inner<'a>(
  time(sess, "pre-AST-expansion lint checks", || {
  lint::check_ast_crate(
  sess,
- &*sess.lint_store.borrow(),
+ lint_store,
  &krate,
  true,
  rustc_lint::BuiltinCombinedPreExpansionLintPass::new());
@@ -539,6 +530,7 @@ fn configure_and_expand_inner<'a>(
 
 pub fn lower_to_hir(
  sess: &Session,
+ lint_store: &lint::LintStore,
  cstore: &CStore,
  resolver: &mut Resolver<'_>,
  dep_graph: &DepGraph,
@@ -559,7 +551,7 @@ pub fn lower_to_hir(
  time(sess, "early lint checks", || {
  lint::check_ast_crate(
  sess,
- &*sess.lint_store.borrow(),
+ lint_store,
  &krate,
  false,
  rustc_lint::BuiltinCombinedEarlyLintPass::new(),
@@ -826,6 +818,7 @@ impl BoxedGlobalCtxt {
 
 pub fn create_global_ctxt(
  compiler: &Compiler,
+ lint_store: Lrc<lint::LintStore>,
  mut hir_forest: hir::map::Forest,
  defs: hir::map::Definitions,
  resolutions: Resolutions,
@@ -863,6 +856,7 @@ pub fn create_global_ctxt(
 
  let gcx = TyCtxt::create_global_ctxt(
  sess,
+ lint_store,
  cstore,
  local_providers,
  extern_providers,

src/librustc_interface/queries.rs

@@ -2,9 +2,11 @@ use crate::interface::{Compiler, Result};
 use crate::passes::{self, BoxedResolver, ExpansionResult, BoxedGlobalCtxt, PluginInfo};
 
 use rustc_incremental::DepGraphFuture;
+use rustc_data_structures::sync::Lrc;
 use rustc::session::config::{OutputFilenames, OutputType};
 use rustc::util::common::{time, ErrorReported};
 use rustc::hir;
+use rustc::lint::LintStore;
 use rustc::hir::def_id::LOCAL_CRATE;
 use rustc::ty::steal::Steal;
 use rustc::dep_graph::DepGraph;
@@ -74,8 +76,8 @@ pub(crate) struct Queries {
  dep_graph_future: Query<Option<DepGraphFuture>>,
  parse: Query<ast::Crate>,
  crate_name: Query<String>,
- register_plugins: Query<(ast::Crate, PluginInfo)>,
- expansion: Query<(ast::Crate, Steal<Rc<RefCell<BoxedResolver>>>)>,
+ register_plugins: Query<(ast::Crate, PluginInfo, Lrc<LintStore>)>,
+ expansion: Query<(ast::Crate, Steal<Rc<RefCell<BoxedResolver>>>, Lrc<LintStore>)>,
  dep_graph: Query<DepGraph>,
  lower_to_hir: Query<(Steal<hir::map::Forest>, ExpansionResult)>,
  prepare_outputs: Query<OutputFilenames>,
@@ -106,7 +108,7 @@ impl Compiler {
  })
  }
 
- pub fn register_plugins(&self) -> Result<&Query<(ast::Crate, PluginInfo)>> {
+ pub fn register_plugins(&self) -> Result<&Query<(ast::Crate, PluginInfo, Lrc<LintStore>)>> {
  self.queries.register_plugins.compute(|| {
  let crate_name = self.crate_name()?.peek().clone();
  let krate = self.parse()?.take();
@@ -148,17 +150,20 @@ impl Compiler {
 
  pub fn expansion(
  &self
- ) -> Result<&Query<(ast::Crate, Steal<Rc<RefCell<BoxedResolver>>>)>> {
+ ) -> Result<&Query<(ast::Crate, Steal<Rc<RefCell<BoxedResolver>>>, Lrc<LintStore>)>> {
  self.queries.expansion.compute(|| {
  let crate_name = self.crate_name()?.peek().clone();
- let (krate, plugin_info) = self.register_plugins()?.take();
+ let (krate, plugin_info, lint_store) = self.register_plugins()?.take();
  passes::configure_and_expand(
  self.sess.clone(),
+ lint_store.clone(),
  self.cstore().clone(),
  krate,
  &crate_name,
  plugin_info,
- ).map(|(krate, resolver)| (krate, Steal::new(Rc::new(RefCell::new(resolver)))))
+ ).map(|(krate, resolver)| {
+ (krate, Steal::new(Rc::new(RefCell::new(resolver))), lint_store)
+ })
  })
  }
 
@@ -185,9 +190,11 @@ impl Compiler {
  let peeked = expansion_result.peek();
  let krate = &peeked.0;
  let resolver = peeked.1.steal();
+ let lint_store = &peeked.2;
  let hir = Steal::new(resolver.borrow_mut().access(|resolver| {
  passes::lower_to_hir(
  self.session(),
+ lint_store,
  self.cstore(),
  resolver,
  &*self.dep_graph()?.peek(),
@@ -212,11 +219,13 @@ impl Compiler {
  self.queries.global_ctxt.compute(|| {
  let crate_name = self.crate_name()?.peek().clone();
  let outputs = self.prepare_outputs()?.peek().clone();
+ let lint_store = self.expansion()?.peek().2.clone();
  let hir = self.lower_to_hir()?;
  let hir = hir.peek();
  let (ref hir_forest, ref expansion) = *hir;
  Ok(passes::create_global_ctxt(
  self,
+ lint_store,
  hir_forest.steal(),
  expansion.defs.steal(),
  expansion.resolutions.steal(),