1 // Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! Implementation of lint checking.
13 //! The lint checking is mostly consolidated into one pass which runs just
14 //! before translation to LLVM bytecode. Throughout compilation, lint warnings
15 //! can be added via the `add_lint` method on the Session structure. This
16 //! requires a span and an id of the node that the lint is being added to. The
17 //! lint isn't actually emitted at that time because it is unknown what the
18 //! actual lint level at that location is.
20 //! To actually emit lint warnings/errors, a separate pass is used just before
21 //! translation. A context keeps track of the current state of all lint levels.
22 //! Upon entering a node of the ast which can modify the lint settings, the
23 //! previous lint state is pushed onto a stack and the ast is then recursed
24 //! upon. As the ast is traversed, this keeps track of the current lint level
25 //! for all lint attributes.
26 use self::TargetLint::*;
28 use dep_graph::DepNode;
29 use middle::privacy::AccessLevels;
31 use session::{config, early_error, Session};
32 use lint::{Level, LevelSource, Lint, LintId, LintArray, LintPass};
33 use lint::{EarlyLintPass, EarlyLintPassObject, LateLintPass, LateLintPassObject};
34 use lint::{Default, CommandLine, Node, Allow, Warn, Deny, Forbid};
36 use util::nodemap::FnvHashMap;
38 use std::cell::RefCell;
40 use std::default::Default as StdDefault;
42 use syntax::ast_util::{self, IdVisitingOperation};
43 use syntax::attr::{self, AttrMetaMethods};
44 use syntax::codemap::Span;
45 use syntax::errors::DiagnosticBuilder;
46 use syntax::parse::token::InternedString;
48 use syntax::attr::ThinAttributesExt;
50 use rustc_front::util;
51 use rustc_front::intravisit as hir_visit;
52 use syntax::visit as ast_visit;
54 /// Information about the registered lints.
56 /// This is basically the subset of `Context` that we can
57 /// build early in the compile pipeline.
58 pub struct LintStore {
59 /// Registered lints. The bool is true if the lint was
60 /// added by a plugin.
61 lints: Vec<(&'static Lint, bool)>,
63 /// Trait objects for each lint pass.
64 /// This is only `None` while iterating over the objects. See the definition
66 early_passes: Option<Vec<EarlyLintPassObject>>,
67 late_passes: Option<Vec<LateLintPassObject>>,
69 /// Lints indexed by name.
70 by_name: FnvHashMap<String, TargetLint>,
72 /// Current levels of each lint, and where they were set.
73 levels: FnvHashMap<LintId, LevelSource>,
75 /// Map of registered lint groups to what lints they expand to. The bool
76 /// is true if the lint group was added by a plugin.
77 lint_groups: FnvHashMap<&'static str, (Vec<LintId>, bool)>,
79 /// Maximum level a lint can be
80 lint_cap: Option<Level>,
83 /// The targed of the `by_name` map, which accounts for renaming/deprecation.
85 /// A direct lint target
88 /// Temporary renaming, used for easing migration pain; see #16545
89 Renamed(String, LintId),
91 /// Lint with this name existed previously, but has been removed/deprecated.
92 /// The string argument is the reason for removal.
102 fn get_level_source(&self, lint: LintId) -> LevelSource {
103 match self.levels.get(&lint) {
105 None => (Allow, Default),
109 fn set_level(&mut self, lint: LintId, mut lvlsrc: LevelSource) {
110 if let Some(cap) = self.lint_cap {
111 lvlsrc.0 = cmp::min(lvlsrc.0, cap);
113 if lvlsrc.0 == Allow {
114 self.levels.remove(&lint);
116 self.levels.insert(lint, lvlsrc);
120 pub fn new() -> LintStore {
123 early_passes: Some(vec!()),
124 late_passes: Some(vec!()),
125 by_name: FnvHashMap(),
126 levels: FnvHashMap(),
127 lint_groups: FnvHashMap(),
132 pub fn get_lints<'t>(&'t self) -> &'t [(&'static Lint, bool)] {
136 pub fn get_lint_groups<'t>(&'t self) -> Vec<(&'static str, Vec<LintId>, bool)> {
137 self.lint_groups.iter().map(|(k, v)| (*k,
142 pub fn register_early_pass(&mut self,
143 sess: Option<&Session>,
145 pass: EarlyLintPassObject) {
146 self.push_pass(sess, from_plugin, &pass);
147 self.early_passes.as_mut().unwrap().push(pass);
150 pub fn register_late_pass(&mut self,
151 sess: Option<&Session>,
153 pass: LateLintPassObject) {
154 self.push_pass(sess, from_plugin, &pass);
155 self.late_passes.as_mut().unwrap().push(pass);
158 // Helper method for register_early/late_pass
159 fn push_pass<P: LintPass + ?Sized + 'static>(&mut self,
160 sess: Option<&Session>,
163 for &lint in pass.get_lints() {
164 self.lints.push((*lint, from_plugin));
166 let id = LintId::of(*lint);
167 if self.by_name.insert(lint.name_lower(), Id(id)).is_some() {
168 let msg = format!("duplicate specification of lint {}", lint.name_lower());
169 match (sess, from_plugin) {
170 // We load builtin lints first, so a duplicate is a compiler bug.
171 // Use early_error when handling -W help with no crate.
172 (None, _) => early_error(config::ErrorOutputType::default(), &msg[..]),
173 (Some(sess), false) => sess.bug(&msg[..]),
175 // A duplicate name from a plugin is a user error.
176 (Some(sess), true) => sess.err(&msg[..]),
180 if lint.default_level != Allow {
181 self.levels.insert(id, (lint.default_level, Default));
186 pub fn register_group(&mut self, sess: Option<&Session>,
187 from_plugin: bool, name: &'static str,
189 let new = self.lint_groups.insert(name, (to, from_plugin)).is_none();
192 let msg = format!("duplicate specification of lint group {}", name);
193 match (sess, from_plugin) {
194 // We load builtin lints first, so a duplicate is a compiler bug.
195 // Use early_error when handling -W help with no crate.
196 (None, _) => early_error(config::ErrorOutputType::default(), &msg[..]),
197 (Some(sess), false) => sess.bug(&msg[..]),
199 // A duplicate name from a plugin is a user error.
200 (Some(sess), true) => sess.err(&msg[..]),
205 pub fn register_renamed(&mut self, old_name: &str, new_name: &str) {
206 let target = match self.by_name.get(new_name) {
207 Some(&Id(lint_id)) => lint_id.clone(),
208 _ => panic!("invalid lint renaming of {} to {}", old_name, new_name)
210 self.by_name.insert(old_name.to_string(), Renamed(new_name.to_string(), target));
213 pub fn register_removed(&mut self, name: &str, reason: &str) {
214 self.by_name.insert(name.into(), Removed(reason.into()));
217 #[allow(unused_variables)]
218 fn find_lint(&self, lint_name: &str, sess: &Session, span: Option<Span>)
219 -> Result<LintId, FindLintError>
221 match self.by_name.get(lint_name) {
222 Some(&Id(lint_id)) => Ok(lint_id),
223 Some(&Renamed(ref new_name, lint_id)) => {
224 let warning = format!("lint {} has been renamed to {}",
225 lint_name, new_name);
227 Some(span) => sess.span_warn(span, &warning[..]),
228 None => sess.warn(&warning[..]),
232 Some(&Removed(ref reason)) => {
233 let warning = format!("lint {} has been removed: {}", lint_name, reason);
235 Some(span) => sess.span_warn(span, &warning[..]),
236 None => sess.warn(&warning[..])
238 Err(FindLintError::Removed)
240 None => Err(FindLintError::NotFound)
244 pub fn process_command_line(&mut self, sess: &Session) {
245 for &(ref lint_name, level) in &sess.opts.lint_opts {
246 match self.find_lint(&lint_name[..], sess, None) {
247 Ok(lint_id) => self.set_level(lint_id, (level, CommandLine)),
249 match self.lint_groups.iter().map(|(&x, pair)| (x, pair.0.clone()))
250 .collect::<FnvHashMap<&'static str,
252 .get(&lint_name[..]) {
255 .map(|lint_id: &LintId|
256 self.set_level(*lint_id, (level, CommandLine)))
257 .collect::<Vec<()>>();
259 None => sess.err(&format!("unknown {} flag: {}",
260 level.as_str(), lint_name)),
266 self.lint_cap = sess.opts.lint_cap;
267 if let Some(cap) = self.lint_cap {
268 for level in self.levels.iter_mut().map(|p| &mut (p.1).0) {
269 *level = cmp::min(*level, cap);
275 /// Context for lint checking after type checking.
276 pub struct LateContext<'a, 'tcx: 'a> {
277 /// Type context we're checking in.
278 pub tcx: &'a ty::ctxt<'tcx>,
280 /// The crate being checked.
281 pub krate: &'a hir::Crate,
283 /// Items accessible from the crate being checked.
284 pub access_levels: &'a AccessLevels,
286 /// The store of registered lints.
289 /// When recursing into an attributed node of the ast which modifies lint
290 /// levels, this stack keeps track of the previous lint levels of whatever
292 level_stack: Vec<(LintId, LevelSource)>,
294 /// Level of lints for certain NodeIds, stored here because the body of
295 /// the lint needs to run in trans.
296 node_levels: RefCell<FnvHashMap<(ast::NodeId, LintId), LevelSource>>,
299 /// Context for lint checking of the AST, after expansion, before lowering to
301 pub struct EarlyContext<'a> {
302 /// Type context we're checking in.
303 pub sess: &'a Session,
305 /// The crate being checked.
306 pub krate: &'a ast::Crate,
308 /// The store of registered lints.
311 /// When recursing into an attributed node of the ast which modifies lint
312 /// levels, this stack keeps track of the previous lint levels of whatever
314 level_stack: Vec<(LintId, LevelSource)>,
317 /// Convenience macro for calling a `LintPass` method on every pass in the context.
318 macro_rules! run_lints { ($cx:expr, $f:ident, $ps:ident, $($args:expr),*) => ({
319 // Move the vector of passes out of `$cx` so that we can
320 // iterate over it mutably while passing `$cx` to the methods.
321 let mut passes = $cx.mut_lints().$ps.take().unwrap();
322 for obj in &mut passes {
323 obj.$f($cx, $($args),*);
325 $cx.mut_lints().$ps = Some(passes);
328 /// Parse the lint attributes into a vector, with `Err`s for malformed lint
329 /// attributes. Writing this as an iterator is an enormous mess.
330 // See also the hir version just below.
331 pub fn gather_attrs(attrs: &[ast::Attribute])
332 -> Vec<Result<(InternedString, Level, Span), Span>> {
333 let mut out = vec!();
335 let level = match Level::from_str(&attr.name()) {
340 attr::mark_used(attr);
342 let meta = &attr.node.value;
343 let metas = match meta.node {
344 ast::MetaList(_, ref metas) => metas,
346 out.push(Err(meta.span));
352 out.push(match meta.node {
353 ast::MetaWord(ref lint_name) => Ok((lint_name.clone(), level, meta.span)),
361 /// Emit a lint as a warning or an error (or not at all)
362 /// according to `level`.
364 /// This lives outside of `Context` so it can be used by checks
365 /// in trans that run after the main lint pass is finished. Most
366 /// lints elsewhere in the compiler should call
367 /// `Session::add_lint()` instead.
368 pub fn raw_emit_lint(sess: &Session,
374 raw_struct_lint(sess, lints, lint, lvlsrc, span, msg).emit();
377 pub fn raw_struct_lint<'a>(sess: &'a Session,
383 -> DiagnosticBuilder<'a> {
384 let (mut level, source) = lvlsrc;
386 return sess.diagnostic().struct_dummy();
389 let name = lint.name_lower();
391 let msg = match source {
393 format!("{}, #[{}({})] on by default", msg,
394 level.as_str(), name)
397 format!("{} [-{} {}]", msg,
399 Warn => 'W', Deny => 'D', Forbid => 'F',
401 }, name.replace("_", "-"))
409 // For purposes of printing, we can treat forbid as deny.
410 if level == Forbid { level = Deny; }
412 let mut err = match (level, span) {
413 (Warn, Some(sp)) => sess.struct_span_warn(sp, &msg[..]),
414 (Warn, None) => sess.struct_warn(&msg[..]),
415 (Deny, Some(sp)) => sess.struct_span_err(sp, &msg[..]),
416 (Deny, None) => sess.struct_err(&msg[..]),
417 _ => sess.bug("impossible level in raw_emit_lint"),
420 // Check for future incompatibility lints and issue a stronger warning.
421 let future_incompat_lints = &lints.lint_groups[builtin::FUTURE_INCOMPATIBLE];
422 let this_id = LintId::of(lint);
423 if future_incompat_lints.0.iter().any(|&id| id == this_id) {
424 let msg = "this lint will become a HARD ERROR in a future release!";
425 if let Some(sp) = span {
426 err.span_note(sp, msg);
432 if let Some(span) = def {
433 err.span_note(span, "lint level defined here");
439 pub trait LintContext: Sized {
440 fn sess(&self) -> &Session;
441 fn lints(&self) -> &LintStore;
442 fn mut_lints(&mut self) -> &mut LintStore;
443 fn level_stack(&mut self) -> &mut Vec<(LintId, LevelSource)>;
444 fn enter_attrs(&mut self, attrs: &[ast::Attribute]);
445 fn exit_attrs(&mut self, attrs: &[ast::Attribute]);
447 /// Get the level of `lint` at the current position of the lint
449 fn current_level(&self, lint: &'static Lint) -> Level {
450 self.lints().levels.get(&LintId::of(lint)).map_or(Allow, |&(lvl, _)| lvl)
453 fn level_src(&self, lint: &'static Lint) -> Option<LevelSource> {
454 self.lints().levels.get(&LintId::of(lint)).map(|ls| match ls {
456 let lint_id = LintId::of(builtin::WARNINGS);
457 (self.lints().get_level_source(lint_id).0, src)
463 fn lookup_and_emit(&self, lint: &'static Lint, span: Option<Span>, msg: &str) {
464 let (level, src) = match self.level_src(lint) {
469 raw_emit_lint(&self.sess(), self.lints(), lint, (level, src), span, msg);
476 -> DiagnosticBuilder {
477 let (level, src) = match self.level_src(lint) {
478 None => return self.sess().diagnostic().struct_dummy(),
482 raw_struct_lint(&self.sess(), self.lints(), lint, (level, src), span, msg)
485 /// Emit a lint at the appropriate level, for a particular span.
486 fn span_lint(&self, lint: &'static Lint, span: Span, msg: &str) {
487 self.lookup_and_emit(lint, Some(span), msg);
490 fn struct_span_lint(&self,
494 -> DiagnosticBuilder {
495 self.lookup(lint, Some(span), msg)
498 /// Emit a lint and note at the appropriate level, for a particular span.
499 fn span_lint_note(&self, lint: &'static Lint, span: Span, msg: &str,
500 note_span: Span, note: &str) {
501 let mut err = self.lookup(lint, Some(span), msg);
502 if self.current_level(lint) != Level::Allow {
503 if note_span == span {
504 err.fileline_note(note_span, note);
506 err.span_note(note_span, note);
512 /// Emit a lint and help at the appropriate level, for a particular span.
513 fn span_lint_help(&self, lint: &'static Lint, span: Span,
514 msg: &str, help: &str) {
515 let mut err = self.lookup(lint, Some(span), msg);
516 self.span_lint(lint, span, msg);
517 if self.current_level(lint) != Level::Allow {
518 err.span_help(span, help);
523 /// Emit a lint at the appropriate level, with no associated span.
524 fn lint(&self, lint: &'static Lint, msg: &str) {
525 self.lookup_and_emit(lint, None, msg);
528 /// Merge the lints specified by any lint attributes into the
529 /// current lint context, call the provided function, then reset the
530 /// lints in effect to their previous state.
531 fn with_lint_attrs<F>(&mut self,
532 attrs: &[ast::Attribute],
534 where F: FnOnce(&mut Self),
536 // Parse all of the lint attributes, and then add them all to the
537 // current dictionary of lint information. Along the way, keep a history
538 // of what we changed so we can roll everything back after invoking the
542 for result in gather_attrs(attrs) {
543 let v = match result {
545 span_err!(self.sess(), span, E0452,
546 "malformed lint attribute");
549 Ok((lint_name, level, span)) => {
550 match self.lints().find_lint(&lint_name, &self.sess(), Some(span)) {
551 Ok(lint_id) => vec![(lint_id, level, span)],
552 Err(FindLintError::NotFound) => {
553 match self.lints().lint_groups.get(&lint_name[..]) {
554 Some(&(ref v, _)) => v.iter()
555 .map(|lint_id: &LintId|
556 (*lint_id, level, span))
559 self.span_lint(builtin::UNKNOWN_LINTS, span,
560 &format!("unknown `{}` attribute: `{}`",
561 level.as_str(), lint_name));
566 Err(FindLintError::Removed) => { continue; }
571 for (lint_id, level, span) in v {
572 let now = self.lints().get_level_source(lint_id).0;
573 if now == Forbid && level != Forbid {
574 let lint_name = lint_id.as_str();
575 span_err!(self.sess(), span, E0453,
576 "{}({}) overruled by outer forbid({})",
577 level.as_str(), lint_name,
579 } else if now != level {
580 let src = self.lints().get_level_source(lint_id).1;
581 self.level_stack().push((lint_id, (now, src)));
583 self.mut_lints().set_level(lint_id, (level, Node(span)));
588 self.enter_attrs(attrs);
590 self.exit_attrs(attrs);
594 let (lint, lvlsrc) = self.level_stack().pop().unwrap();
595 self.mut_lints().set_level(lint, lvlsrc);
601 impl<'a> EarlyContext<'a> {
602 fn new(sess: &'a Session,
603 krate: &'a ast::Crate) -> EarlyContext<'a> {
604 // We want to own the lint store, so move it out of the session. Remember
605 // to put it back later...
606 let lint_store = mem::replace(&mut *sess.lint_store.borrow_mut(),
616 fn visit_ids<F>(&mut self, f: F)
617 where F: FnOnce(&mut ast_util::IdVisitor<EarlyContext>)
619 let mut v = ast_util::IdVisitor {
621 visited_outermost: false,
627 impl<'a, 'tcx> LateContext<'a, 'tcx> {
628 fn new(tcx: &'a ty::ctxt<'tcx>,
629 krate: &'a hir::Crate,
630 access_levels: &'a AccessLevels) -> LateContext<'a, 'tcx> {
631 // We want to own the lint store, so move it out of the session.
632 let lint_store = mem::replace(&mut *tcx.sess.lint_store.borrow_mut(),
638 access_levels: access_levels,
641 node_levels: RefCell::new(FnvHashMap()),
645 fn visit_ids<F>(&mut self, f: F)
646 where F: FnOnce(&mut util::IdVisitor<LateContext>)
648 let mut v = util::IdVisitor::new(self);
653 impl<'a, 'tcx> LintContext for LateContext<'a, 'tcx> {
654 /// Get the overall compiler `Session` object.
655 fn sess(&self) -> &Session {
659 fn lints(&self) -> &LintStore {
663 fn mut_lints(&mut self) -> &mut LintStore {
667 fn level_stack(&mut self) -> &mut Vec<(LintId, LevelSource)> {
668 &mut self.level_stack
671 fn enter_attrs(&mut self, attrs: &[ast::Attribute]) {
672 debug!("late context: enter_attrs({:?})", attrs);
673 run_lints!(self, enter_lint_attrs, late_passes, attrs);
676 fn exit_attrs(&mut self, attrs: &[ast::Attribute]) {
677 debug!("late context: exit_attrs({:?})", attrs);
678 run_lints!(self, exit_lint_attrs, late_passes, attrs);
682 impl<'a> LintContext for EarlyContext<'a> {
683 /// Get the overall compiler `Session` object.
684 fn sess(&self) -> &Session {
688 fn lints(&self) -> &LintStore {
692 fn mut_lints(&mut self) -> &mut LintStore {
696 fn level_stack(&mut self) -> &mut Vec<(LintId, LevelSource)> {
697 &mut self.level_stack
700 fn enter_attrs(&mut self, attrs: &[ast::Attribute]) {
701 debug!("early context: exit_attrs({:?})", attrs);
702 run_lints!(self, enter_lint_attrs, early_passes, attrs);
705 fn exit_attrs(&mut self, attrs: &[ast::Attribute]) {
706 debug!("early context: exit_attrs({:?})", attrs);
707 run_lints!(self, exit_lint_attrs, early_passes, attrs);
711 impl<'a, 'tcx, 'v> hir_visit::Visitor<'v> for LateContext<'a, 'tcx> {
712 /// Because lints are scoped lexically, we want to walk nested
713 /// items in the context of the outer item, so enable
715 fn visit_nested_item(&mut self, item: hir::ItemId) {
716 self.visit_item(self.tcx.map.expect_item(item.id))
719 fn visit_item(&mut self, it: &hir::Item) {
720 self.with_lint_attrs(&it.attrs, |cx| {
721 run_lints!(cx, check_item, late_passes, it);
722 cx.visit_ids(|v| v.visit_item(it));
723 hir_visit::walk_item(cx, it);
727 fn visit_foreign_item(&mut self, it: &hir::ForeignItem) {
728 self.with_lint_attrs(&it.attrs, |cx| {
729 run_lints!(cx, check_foreign_item, late_passes, it);
730 hir_visit::walk_foreign_item(cx, it);
734 fn visit_pat(&mut self, p: &hir::Pat) {
735 run_lints!(self, check_pat, late_passes, p);
736 hir_visit::walk_pat(self, p);
739 fn visit_expr(&mut self, e: &hir::Expr) {
740 self.with_lint_attrs(e.attrs.as_attr_slice(), |cx| {
741 run_lints!(cx, check_expr, late_passes, e);
742 hir_visit::walk_expr(cx, e);
746 fn visit_stmt(&mut self, s: &hir::Stmt) {
747 // statement attributes are actually just attributes on one of
751 // so we keep track of lint levels there
752 run_lints!(self, check_stmt, late_passes, s);
753 hir_visit::walk_stmt(self, s);
756 fn visit_fn(&mut self, fk: hir_visit::FnKind<'v>, decl: &'v hir::FnDecl,
757 body: &'v hir::Block, span: Span, id: ast::NodeId) {
758 run_lints!(self, check_fn, late_passes, fk, decl, body, span, id);
759 hir_visit::walk_fn(self, fk, decl, body, span);
762 fn visit_variant_data(&mut self,
763 s: &hir::VariantData,
766 item_id: ast::NodeId,
768 run_lints!(self, check_struct_def, late_passes, s, name, g, item_id);
769 hir_visit::walk_struct_def(self, s);
770 run_lints!(self, check_struct_def_post, late_passes, s, name, g, item_id);
773 fn visit_struct_field(&mut self, s: &hir::StructField) {
774 self.with_lint_attrs(&s.node.attrs, |cx| {
775 run_lints!(cx, check_struct_field, late_passes, s);
776 hir_visit::walk_struct_field(cx, s);
780 fn visit_variant(&mut self, v: &hir::Variant, g: &hir::Generics, item_id: ast::NodeId) {
781 self.with_lint_attrs(&v.node.attrs, |cx| {
782 run_lints!(cx, check_variant, late_passes, v, g);
783 hir_visit::walk_variant(cx, v, g, item_id);
784 run_lints!(cx, check_variant_post, late_passes, v, g);
788 fn visit_ty(&mut self, t: &hir::Ty) {
789 run_lints!(self, check_ty, late_passes, t);
790 hir_visit::walk_ty(self, t);
793 fn visit_name(&mut self, sp: Span, name: ast::Name) {
794 run_lints!(self, check_name, late_passes, sp, name);
797 fn visit_mod(&mut self, m: &hir::Mod, s: Span, n: ast::NodeId) {
798 run_lints!(self, check_mod, late_passes, m, s, n);
799 hir_visit::walk_mod(self, m);
802 fn visit_local(&mut self, l: &hir::Local) {
803 self.with_lint_attrs(l.attrs.as_attr_slice(), |cx| {
804 run_lints!(cx, check_local, late_passes, l);
805 hir_visit::walk_local(cx, l);
809 fn visit_block(&mut self, b: &hir::Block) {
810 run_lints!(self, check_block, late_passes, b);
811 hir_visit::walk_block(self, b);
814 fn visit_arm(&mut self, a: &hir::Arm) {
815 run_lints!(self, check_arm, late_passes, a);
816 hir_visit::walk_arm(self, a);
819 fn visit_decl(&mut self, d: &hir::Decl) {
820 run_lints!(self, check_decl, late_passes, d);
821 hir_visit::walk_decl(self, d);
824 fn visit_expr_post(&mut self, e: &hir::Expr) {
825 run_lints!(self, check_expr_post, late_passes, e);
828 fn visit_generics(&mut self, g: &hir::Generics) {
829 run_lints!(self, check_generics, late_passes, g);
830 hir_visit::walk_generics(self, g);
833 fn visit_trait_item(&mut self, trait_item: &hir::TraitItem) {
834 self.with_lint_attrs(&trait_item.attrs, |cx| {
835 run_lints!(cx, check_trait_item, late_passes, trait_item);
836 cx.visit_ids(|v| v.visit_trait_item(trait_item));
837 hir_visit::walk_trait_item(cx, trait_item);
841 fn visit_impl_item(&mut self, impl_item: &hir::ImplItem) {
842 self.with_lint_attrs(&impl_item.attrs, |cx| {
843 run_lints!(cx, check_impl_item, late_passes, impl_item);
844 cx.visit_ids(|v| v.visit_impl_item(impl_item));
845 hir_visit::walk_impl_item(cx, impl_item);
849 fn visit_lifetime(&mut self, lt: &hir::Lifetime) {
850 run_lints!(self, check_lifetime, late_passes, lt);
853 fn visit_lifetime_def(&mut self, lt: &hir::LifetimeDef) {
854 run_lints!(self, check_lifetime_def, late_passes, lt);
857 fn visit_explicit_self(&mut self, es: &hir::ExplicitSelf) {
858 run_lints!(self, check_explicit_self, late_passes, es);
859 hir_visit::walk_explicit_self(self, es);
862 fn visit_path(&mut self, p: &hir::Path, id: ast::NodeId) {
863 run_lints!(self, check_path, late_passes, p, id);
864 hir_visit::walk_path(self, p);
867 fn visit_path_list_item(&mut self, prefix: &hir::Path, item: &hir::PathListItem) {
868 run_lints!(self, check_path_list_item, late_passes, item);
869 hir_visit::walk_path_list_item(self, prefix, item);
872 fn visit_attribute(&mut self, attr: &ast::Attribute) {
873 run_lints!(self, check_attribute, late_passes, attr);
877 impl<'a, 'v> ast_visit::Visitor<'v> for EarlyContext<'a> {
878 fn visit_item(&mut self, it: &ast::Item) {
879 self.with_lint_attrs(&it.attrs, |cx| {
880 run_lints!(cx, check_item, early_passes, it);
881 cx.visit_ids(|v| v.visit_item(it));
882 ast_visit::walk_item(cx, it);
886 fn visit_foreign_item(&mut self, it: &ast::ForeignItem) {
887 self.with_lint_attrs(&it.attrs, |cx| {
888 run_lints!(cx, check_foreign_item, early_passes, it);
889 ast_visit::walk_foreign_item(cx, it);
893 fn visit_pat(&mut self, p: &ast::Pat) {
894 run_lints!(self, check_pat, early_passes, p);
895 ast_visit::walk_pat(self, p);
898 fn visit_expr(&mut self, e: &ast::Expr) {
899 run_lints!(self, check_expr, early_passes, e);
900 ast_visit::walk_expr(self, e);
903 fn visit_stmt(&mut self, s: &ast::Stmt) {
904 run_lints!(self, check_stmt, early_passes, s);
905 ast_visit::walk_stmt(self, s);
908 fn visit_fn(&mut self, fk: ast_visit::FnKind<'v>, decl: &'v ast::FnDecl,
909 body: &'v ast::Block, span: Span, id: ast::NodeId) {
910 run_lints!(self, check_fn, early_passes, fk, decl, body, span, id);
911 ast_visit::walk_fn(self, fk, decl, body, span);
914 fn visit_variant_data(&mut self,
915 s: &ast::VariantData,
918 item_id: ast::NodeId,
920 run_lints!(self, check_struct_def, early_passes, s, ident, g, item_id);
921 ast_visit::walk_struct_def(self, s);
922 run_lints!(self, check_struct_def_post, early_passes, s, ident, g, item_id);
925 fn visit_struct_field(&mut self, s: &ast::StructField) {
926 self.with_lint_attrs(&s.node.attrs, |cx| {
927 run_lints!(cx, check_struct_field, early_passes, s);
928 ast_visit::walk_struct_field(cx, s);
932 fn visit_variant(&mut self, v: &ast::Variant, g: &ast::Generics, item_id: ast::NodeId) {
933 self.with_lint_attrs(&v.node.attrs, |cx| {
934 run_lints!(cx, check_variant, early_passes, v, g);
935 ast_visit::walk_variant(cx, v, g, item_id);
936 run_lints!(cx, check_variant_post, early_passes, v, g);
940 fn visit_ty(&mut self, t: &ast::Ty) {
941 run_lints!(self, check_ty, early_passes, t);
942 ast_visit::walk_ty(self, t);
945 fn visit_ident(&mut self, sp: Span, id: ast::Ident) {
946 run_lints!(self, check_ident, early_passes, sp, id);
949 fn visit_mod(&mut self, m: &ast::Mod, s: Span, n: ast::NodeId) {
950 run_lints!(self, check_mod, early_passes, m, s, n);
951 ast_visit::walk_mod(self, m);
954 fn visit_local(&mut self, l: &ast::Local) {
955 run_lints!(self, check_local, early_passes, l);
956 ast_visit::walk_local(self, l);
959 fn visit_block(&mut self, b: &ast::Block) {
960 run_lints!(self, check_block, early_passes, b);
961 ast_visit::walk_block(self, b);
964 fn visit_arm(&mut self, a: &ast::Arm) {
965 run_lints!(self, check_arm, early_passes, a);
966 ast_visit::walk_arm(self, a);
969 fn visit_decl(&mut self, d: &ast::Decl) {
970 run_lints!(self, check_decl, early_passes, d);
971 ast_visit::walk_decl(self, d);
974 fn visit_expr_post(&mut self, e: &ast::Expr) {
975 run_lints!(self, check_expr_post, early_passes, e);
978 fn visit_generics(&mut self, g: &ast::Generics) {
979 run_lints!(self, check_generics, early_passes, g);
980 ast_visit::walk_generics(self, g);
983 fn visit_trait_item(&mut self, trait_item: &ast::TraitItem) {
984 self.with_lint_attrs(&trait_item.attrs, |cx| {
985 run_lints!(cx, check_trait_item, early_passes, trait_item);
986 cx.visit_ids(|v| v.visit_trait_item(trait_item));
987 ast_visit::walk_trait_item(cx, trait_item);
991 fn visit_impl_item(&mut self, impl_item: &ast::ImplItem) {
992 self.with_lint_attrs(&impl_item.attrs, |cx| {
993 run_lints!(cx, check_impl_item, early_passes, impl_item);
994 cx.visit_ids(|v| v.visit_impl_item(impl_item));
995 ast_visit::walk_impl_item(cx, impl_item);
999 fn visit_lifetime(&mut self, lt: &ast::Lifetime) {
1000 run_lints!(self, check_lifetime, early_passes, lt);
1003 fn visit_lifetime_def(&mut self, lt: &ast::LifetimeDef) {
1004 run_lints!(self, check_lifetime_def, early_passes, lt);
1007 fn visit_explicit_self(&mut self, es: &ast::ExplicitSelf) {
1008 run_lints!(self, check_explicit_self, early_passes, es);
1009 ast_visit::walk_explicit_self(self, es);
1012 fn visit_path(&mut self, p: &ast::Path, id: ast::NodeId) {
1013 run_lints!(self, check_path, early_passes, p, id);
1014 ast_visit::walk_path(self, p);
1017 fn visit_path_list_item(&mut self, prefix: &ast::Path, item: &ast::PathListItem) {
1018 run_lints!(self, check_path_list_item, early_passes, item);
1019 ast_visit::walk_path_list_item(self, prefix, item);
1022 fn visit_attribute(&mut self, attr: &ast::Attribute) {
1023 run_lints!(self, check_attribute, early_passes, attr);
1027 // Output any lints that were previously added to the session.
1028 impl<'a, 'tcx> IdVisitingOperation for LateContext<'a, 'tcx> {
1029 fn visit_id(&mut self, id: ast::NodeId) {
1030 match self.sess().lints.borrow_mut().remove(&id) {
1033 debug!("LateContext::visit_id: id={:?} lints={:?}", id, lints);
1034 for (lint_id, span, msg) in lints {
1035 self.span_lint(lint_id.lint, span, &msg[..])
1041 impl<'a> IdVisitingOperation for EarlyContext<'a> {
1042 fn visit_id(&mut self, id: ast::NodeId) {
1043 match self.sess.lints.borrow_mut().remove(&id) {
1046 for (lint_id, span, msg) in lints {
1047 self.span_lint(lint_id.lint, span, &msg[..])
1054 // This lint pass is defined here because it touches parts of the `LateContext`
1055 // that we don't want to expose. It records the lint level at certain AST
1056 // nodes, so that the variant size difference check in trans can call
1059 pub struct GatherNodeLevels;
1061 impl LintPass for GatherNodeLevels {
1062 fn get_lints(&self) -> LintArray {
1067 impl LateLintPass for GatherNodeLevels {
1068 fn check_item(&mut self, cx: &LateContext, it: &hir::Item) {
1070 hir::ItemEnum(..) => {
1071 let lint_id = LintId::of(builtin::VARIANT_SIZE_DIFFERENCES);
1072 let lvlsrc = cx.lints.get_level_source(lint_id);
1074 (lvl, _) if lvl != Allow => {
1075 cx.node_levels.borrow_mut()
1076 .insert((it.id, lint_id), lvlsrc);
1086 /// Perform lint checking on a crate.
1088 /// Consumes the `lint_store` field of the `Session`.
1089 pub fn check_crate(tcx: &ty::ctxt, access_levels: &AccessLevels) {
1090 let _task = tcx.dep_graph.in_task(DepNode::LateLintCheck);
1092 let krate = tcx.map.krate();
1093 let mut cx = LateContext::new(tcx, krate, access_levels);
1095 // Visit the whole crate.
1096 cx.with_lint_attrs(&krate.attrs, |cx| {
1097 cx.visit_id(ast::CRATE_NODE_ID);
1099 hir_visit::walk_crate(v, krate);
1102 // since the root module isn't visited as an item (because it isn't an
1103 // item), warn for it here.
1104 run_lints!(cx, check_crate, late_passes, krate);
1106 hir_visit::walk_crate(cx, krate);
1109 // If we missed any lints added to the session, then there's a bug somewhere
1110 // in the iteration code.
1111 for (id, v) in tcx.sess.lints.borrow().iter() {
1112 for &(lint, span, ref msg) in v {
1113 tcx.sess.span_bug(span,
1114 &format!("unprocessed lint {} at {}: {}",
1115 lint.as_str(), tcx.map.node_to_string(*id), *msg))
1119 *tcx.node_lint_levels.borrow_mut() = cx.node_levels.into_inner();
1122 pub fn check_ast_crate(sess: &Session, krate: &ast::Crate) {
1123 let mut cx = EarlyContext::new(sess, krate);
1125 // Visit the whole crate.
1126 cx.with_lint_attrs(&krate.attrs, |cx| {
1127 cx.visit_id(ast::CRATE_NODE_ID);
1129 v.visited_outermost = true;
1130 ast_visit::walk_crate(v, krate);
1133 // since the root module isn't visited as an item (because it isn't an
1134 // item), warn for it here.
1135 run_lints!(cx, check_crate, early_passes, krate);
1137 ast_visit::walk_crate(cx, krate);
1140 // Put the lint store back in the session.
1141 mem::replace(&mut *sess.lint_store.borrow_mut(), cx.lints);
1143 // If we missed any lints added to the session, then there's a bug somewhere
1144 // in the iteration code.
1145 for (_, v) in sess.lints.borrow().iter() {
1146 for &(lint, span, ref msg) in v {
1148 &format!("unprocessed lint {}: {}",
1149 lint.as_str(), *msg))