1 // Copyright 2012-2014 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 middle::privacy::ExportedItems;
30 use middle::ty::{mod, Ty};
31 use middle::typeck::astconv::AstConv;
32 use middle::typeck::infer;
33 use session::{early_error, Session};
34 use lint::{Level, LevelSource, Lint, LintId, LintArray, LintPass, LintPassObject};
35 use lint::{Default, CommandLine, Node, Allow, Warn, Deny, Forbid};
37 use util::nodemap::FnvHashMap;
40 use std::cell::RefCell;
41 use std::tuple::Tuple2;
43 use syntax::ast_util::IdVisitingOperation;
44 use syntax::attr::AttrMetaMethods;
46 use syntax::codemap::Span;
47 use syntax::visit::{Visitor, FnKind};
48 use syntax::parse::token::InternedString;
49 use syntax::{ast, ast_util, visit};
51 /// Information about the registered lints.
53 /// This is basically the subset of `Context` that we can
54 /// build early in the compile pipeline.
55 pub struct LintStore {
56 /// Registered lints. The bool is true if the lint was
57 /// added by a plugin.
58 lints: Vec<(&'static Lint, bool)>,
60 /// Trait objects for each lint pass.
61 /// This is only `None` while iterating over the objects. See the definition
63 passes: Option<Vec<LintPassObject>>,
65 /// Lints indexed by name.
66 by_name: FnvHashMap<String, TargetLint>,
68 /// Current levels of each lint, and where they were set.
69 levels: FnvHashMap<LintId, LevelSource>,
71 /// Map of registered lint groups to what lints they expand to. The bool
72 /// is true if the lint group was added by a plugin.
73 lint_groups: FnvHashMap<&'static str, (Vec<LintId>, bool)>,
76 /// The targed of the `by_name` map, which accounts for renaming/deprecation.
78 /// A direct lint target
81 /// Temporary renaming, used for easing migration pain; see #16545
82 Renamed(String, LintId),
86 fn get_level_source(&self, lint: LintId) -> LevelSource {
87 match self.levels.get(&lint) {
89 None => (Allow, Default),
93 fn set_level(&mut self, lint: LintId, lvlsrc: LevelSource) {
94 if lvlsrc.val0() == Allow {
95 self.levels.remove(&lint);
97 self.levels.insert(lint, lvlsrc);
101 pub fn new() -> LintStore {
104 passes: Some(vec!()),
105 by_name: FnvHashMap::new(),
106 levels: FnvHashMap::new(),
107 lint_groups: FnvHashMap::new(),
111 pub fn get_lints<'t>(&'t self) -> &'t [(&'static Lint, bool)] {
112 self.lints.as_slice()
115 pub fn get_lint_groups<'t>(&'t self) -> Vec<(&'static str, Vec<LintId>, bool)> {
116 self.lint_groups.iter().map(|(k, v)| (*k,
118 *v.ref1())).collect()
121 pub fn register_pass(&mut self, sess: Option<&Session>,
122 from_plugin: bool, pass: LintPassObject) {
123 for &lint in pass.get_lints().iter() {
124 self.lints.push((*lint, from_plugin));
126 let id = LintId::of(*lint);
127 if self.by_name.insert(lint.name_lower(), Id(id)).is_some() {
128 let msg = format!("duplicate specification of lint {}", lint.name_lower());
129 match (sess, from_plugin) {
130 // We load builtin lints first, so a duplicate is a compiler bug.
131 // Use early_error when handling -W help with no crate.
132 (None, _) => early_error(msg.as_slice()),
133 (Some(sess), false) => sess.bug(msg.as_slice()),
135 // A duplicate name from a plugin is a user error.
136 (Some(sess), true) => sess.err(msg.as_slice()),
140 if lint.default_level != Allow {
141 self.levels.insert(id, (lint.default_level, Default));
144 self.passes.as_mut().unwrap().push(pass);
147 pub fn register_group(&mut self, sess: Option<&Session>,
148 from_plugin: bool, name: &'static str,
150 let new = self.lint_groups.insert(name, (to, from_plugin)).is_none();
153 let msg = format!("duplicate specification of lint group {}", name);
154 match (sess, from_plugin) {
155 // We load builtin lints first, so a duplicate is a compiler bug.
156 // Use early_error when handling -W help with no crate.
157 (None, _) => early_error(msg.as_slice()),
158 (Some(sess), false) => sess.bug(msg.as_slice()),
160 // A duplicate name from a plugin is a user error.
161 (Some(sess), true) => sess.err(msg.as_slice()),
166 fn register_renamed(&mut self, old_name: &str, new_name: &str) {
167 let target = match self.by_name.get(new_name) {
168 Some(&Id(lint_id)) => lint_id.clone(),
169 _ => panic!("invalid lint renaming of {} to {}", old_name, new_name)
171 self.by_name.insert(old_name.to_string(), Renamed(new_name.to_string(), target));
174 pub fn register_builtin(&mut self, sess: Option<&Session>) {
175 macro_rules! add_builtin ( ( $sess:ident, $($name:ident),*, ) => (
177 self.register_pass($sess, false, box builtin::$name as LintPassObject);
181 macro_rules! add_builtin_with_new ( ( $sess:ident, $($name:ident),*, ) => (
183 self.register_pass($sess, false, box builtin::$name::new() as LintPassObject);
187 macro_rules! add_lint_group ( ( $sess:ident, $name:expr, $($lint:ident),* ) => (
188 self.register_group($sess, false, $name, vec![$(LintId::of(builtin::$lint)),*]);
205 NonShorthandFieldPatterns,
213 add_builtin_with_new!(sess,
219 add_lint_group!(sess, "bad_style",
220 NON_CAMEL_CASE_TYPES, NON_SNAKE_CASE, NON_UPPER_CASE_GLOBALS)
222 add_lint_group!(sess, "unused",
223 UNUSED_IMPORTS, UNUSED_VARIABLES, UNUSED_ASSIGNMENTS, DEAD_CODE,
224 UNUSED_MUT, UNREACHABLE_CODE, UNUSED_MUST_USE,
225 UNUSED_UNSAFE, PATH_STATEMENTS)
227 // We have one lint pass defined in this module.
228 self.register_pass(sess, false, box GatherNodeLevels as LintPassObject);
230 // Insert temporary renamings for a one-time deprecation (#16545)
231 self.register_renamed("unnecessary_typecast", "unused_typecasts");
232 self.register_renamed("unsigned_negate", "unsigned_negation");
233 self.register_renamed("type_limits", "unused_comparisons");
234 self.register_renamed("type_overflow", "overflowing_literals");
235 self.register_renamed("ctypes", "improper_ctypes");
236 self.register_renamed("owned_heap_memory", "box_pointers");
237 self.register_renamed("unused_attribute", "unused_attributes");
238 self.register_renamed("path_statement", "path_statements");
239 self.register_renamed("unused_result", "unused_results");
240 self.register_renamed("non_uppercase_statics", "non_upper_case_globals");
241 self.register_renamed("unnecessary_parens", "unused_parens");
242 self.register_renamed("unnecessary_import_braces", "unused_import_braces");
243 self.register_renamed("unsafe_block", "unsafe_blocks");
244 self.register_renamed("unnecessary_allocation", "unused_allocation");
245 self.register_renamed("missing_doc", "missing_docs");
246 self.register_renamed("unused_extern_crate", "unused_extern_crates");
247 self.register_renamed("unnecessary_qualification", "unused_qualifications");
248 self.register_renamed("unrecognized_lint", "unknown_lints");
249 self.register_renamed("unused_variable", "unused_variables");
250 self.register_renamed("dead_assignment", "unused_assignments");
251 self.register_renamed("unknown_crate_type", "unknown_crate_types");
252 self.register_renamed("variant_size_difference", "variant_size_differences");
253 self.register_renamed("transmute_fat_ptr", "fat_ptr_transmutes");
257 #[allow(unused_variables)]
258 fn find_lint(&self, lint_name: &str, sess: &Session, span: Option<Span>)
261 match self.by_name.get(lint_name) {
262 Some(&Id(lint_id)) => Some(lint_id),
263 Some(&Renamed(ref new_name, lint_id)) => {
264 let warning = format!("lint {} has been renamed to {}",
265 lint_name, new_name);
267 Some(span) => sess.span_warn(span, warning.as_slice()),
268 None => sess.warn(warning.as_slice()),
276 pub fn process_command_line(&mut self, sess: &Session) {
277 for &(ref lint_name, level) in sess.opts.lint_opts.iter() {
278 match self.find_lint(lint_name.as_slice(), sess, None) {
279 Some(lint_id) => self.set_level(lint_id, (level, CommandLine)),
281 match self.lint_groups.iter().map(|(&x, pair)| (x, pair.ref0().clone()))
282 .collect::<FnvHashMap<&'static str,
284 .get(lint_name.as_slice()) {
287 .map(|lint_id: &LintId|
288 self.set_level(*lint_id, (level, CommandLine)))
289 .collect::<Vec<()>>();
291 None => sess.err(format!("unknown {} flag: {}",
292 level.as_str(), lint_name).as_slice()),
300 /// Context for lint checking.
301 pub struct Context<'a, 'tcx: 'a> {
302 /// Type context we're checking in.
303 pub tcx: &'a ty::ctxt<'tcx>,
305 /// The crate being checked.
306 pub krate: &'a ast::Crate,
308 /// Items exported from the crate being checked.
309 pub exported_items: &'a ExportedItems,
311 /// The store of registered lints.
314 /// When recursing into an attributed node of the ast which modifies lint
315 /// levels, this stack keeps track of the previous lint levels of whatever
317 level_stack: Vec<(LintId, LevelSource)>,
319 /// Level of lints for certain NodeIds, stored here because the body of
320 /// the lint needs to run in trans.
321 node_levels: RefCell<FnvHashMap<(ast::NodeId, LintId), LevelSource>>,
324 /// Convenience macro for calling a `LintPass` method on every pass in the context.
325 macro_rules! run_lints ( ($cx:expr, $f:ident, $($args:expr),*) => ({
326 // Move the vector of passes out of `$cx` so that we can
327 // iterate over it mutably while passing `$cx` to the methods.
328 let mut passes = $cx.lints.passes.take().unwrap();
329 for obj in passes.iter_mut() {
330 obj.$f($cx, $($args),*);
332 $cx.lints.passes = Some(passes);
335 /// Parse the lint attributes into a vector, with `Err`s for malformed lint
336 /// attributes. Writing this as an iterator is an enormous mess.
337 pub fn gather_attrs(attrs: &[ast::Attribute])
338 -> Vec<Result<(InternedString, Level, Span), Span>> {
339 let mut out = vec!();
340 for attr in attrs.iter() {
341 let level = match Level::from_str(attr.name().get()) {
346 attr::mark_used(attr);
348 let meta = &attr.node.value;
349 let metas = match meta.node {
350 ast::MetaList(_, ref metas) => metas,
352 out.push(Err(meta.span));
357 for meta in metas.iter() {
358 out.push(match meta.node {
359 ast::MetaWord(ref lint_name) => Ok((lint_name.clone(), level, meta.span)),
367 /// Emit a lint as a warning or an error (or not at all)
368 /// according to `level`.
370 /// This lives outside of `Context` so it can be used by checks
371 /// in trans that run after the main lint pass is finished. Most
372 /// lints elsewhere in the compiler should call
373 /// `Session::add_lint()` instead.
374 pub fn raw_emit_lint(sess: &Session, lint: &'static Lint,
375 lvlsrc: LevelSource, span: Option<Span>, msg: &str) {
376 let (mut level, source) = lvlsrc;
377 if level == Allow { return }
379 let name = lint.name_lower();
381 let msg = match source {
383 format!("{}, #[{}({})] on by default", msg,
384 level.as_str(), name)
387 format!("{} [-{} {}]", msg,
389 Warn => 'W', Deny => 'D', Forbid => 'F',
391 }, name.replace("_", "-"))
399 // For purposes of printing, we can treat forbid as deny.
400 if level == Forbid { level = Deny; }
402 match (level, span) {
403 (Warn, Some(sp)) => sess.span_warn(sp, msg.as_slice()),
404 (Warn, None) => sess.warn(msg.as_slice()),
405 (Deny, Some(sp)) => sess.span_err(sp, msg.as_slice()),
406 (Deny, None) => sess.err(msg.as_slice()),
407 _ => sess.bug("impossible level in raw_emit_lint"),
410 for span in note.into_iter() {
411 sess.span_note(span, "lint level defined here");
415 impl<'a, 'tcx> Context<'a, 'tcx> {
416 fn new(tcx: &'a ty::ctxt<'tcx>,
417 krate: &'a ast::Crate,
418 exported_items: &'a ExportedItems) -> Context<'a, 'tcx> {
419 // We want to own the lint store, so move it out of the session.
420 let lint_store = mem::replace(&mut *tcx.sess.lint_store.borrow_mut(),
426 exported_items: exported_items,
429 node_levels: RefCell::new(FnvHashMap::new()),
433 /// Get the overall compiler `Session` object.
434 pub fn sess(&'a self) -> &'a Session {
438 /// Get the level of `lint` at the current position of the lint
440 pub fn current_level(&self, lint: &'static Lint) -> Level {
441 self.lints.levels.get(&LintId::of(lint)).map_or(Allow, |&(lvl, _)| lvl)
444 fn lookup_and_emit(&self, lint: &'static Lint, span: Option<Span>, msg: &str) {
445 let (level, src) = match self.lints.levels.get(&LintId::of(lint)) {
447 Some(&(Warn, src)) => {
448 let lint_id = LintId::of(builtin::WARNINGS);
449 (self.lints.get_level_source(lint_id).val0(), src)
454 raw_emit_lint(&self.tcx.sess, lint, (level, src), span, msg);
457 /// Emit a lint at the appropriate level, with no associated span.
458 pub fn lint(&self, lint: &'static Lint, msg: &str) {
459 self.lookup_and_emit(lint, None, msg);
462 /// Emit a lint at the appropriate level, for a particular span.
463 pub fn span_lint(&self, lint: &'static Lint, span: Span, msg: &str) {
464 self.lookup_and_emit(lint, Some(span), msg);
468 * Merge the lints specified by any lint attributes into the
469 * current lint context, call the provided function, then reset the
470 * lints in effect to their previous state.
472 fn with_lint_attrs(&mut self,
473 attrs: &[ast::Attribute],
475 // Parse all of the lint attributes, and then add them all to the
476 // current dictionary of lint information. Along the way, keep a history
477 // of what we changed so we can roll everything back after invoking the
481 for result in gather_attrs(attrs).into_iter() {
482 let v = match result {
484 self.tcx.sess.span_err(span, "malformed lint attribute");
487 Ok((lint_name, level, span)) => {
488 match self.lints.find_lint(lint_name.get(), &self.tcx.sess, Some(span)) {
489 Some(lint_id) => vec![(lint_id, level, span)],
491 match self.lints.lint_groups.get(lint_name.get()) {
492 Some(&(ref v, _)) => v.iter()
493 .map(|lint_id: &LintId|
494 (*lint_id, level, span))
497 self.span_lint(builtin::UNKNOWN_LINTS, span,
498 format!("unknown `{}` attribute: `{}`",
499 level.as_str(), lint_name).as_slice());
508 for (lint_id, level, span) in v.into_iter() {
509 let now = self.lints.get_level_source(lint_id).val0();
510 if now == Forbid && level != Forbid {
511 let lint_name = lint_id.as_str();
512 self.tcx.sess.span_err(span,
513 format!("{}({}) overruled by outer forbid({})",
514 level.as_str(), lint_name,
515 lint_name).as_slice());
516 } else if now != level {
517 let src = self.lints.get_level_source(lint_id).val1();
518 self.level_stack.push((lint_id, (now, src)));
520 self.lints.set_level(lint_id, (level, Node(span)));
525 run_lints!(self, enter_lint_attrs, attrs);
527 run_lints!(self, exit_lint_attrs, attrs);
530 for _ in range(0, pushed) {
531 let (lint, lvlsrc) = self.level_stack.pop().unwrap();
532 self.lints.set_level(lint, lvlsrc);
536 fn visit_ids(&mut self, f: |&mut ast_util::IdVisitor<Context>|) {
537 let mut v = ast_util::IdVisitor {
539 pass_through_items: false,
540 visited_outermost: false,
546 impl<'a, 'tcx> AstConv<'tcx> for Context<'a, 'tcx>{
547 fn tcx<'a>(&'a self) -> &'a ty::ctxt<'tcx> { self.tcx }
549 fn get_item_ty(&self, id: ast::DefId) -> ty::Polytype<'tcx> {
550 ty::lookup_item_type(self.tcx, id)
553 fn get_trait_def(&self, id: ast::DefId) -> Rc<ty::TraitDef<'tcx>> {
554 ty::lookup_trait_def(self.tcx, id)
557 fn ty_infer(&self, _span: Span) -> Ty<'tcx> {
558 infer::new_infer_ctxt(self.tcx).next_ty_var()
561 fn associated_types_of_trait_are_valid(&self, _: Ty<'tcx>, _: ast::DefId)
563 // FIXME(pcwalton): This is wrong.
567 fn associated_type_binding(&self,
570 trait_id: ast::DefId,
571 associated_type_id: ast::DefId)
573 // FIXME(pcwalton): This is wrong.
574 let trait_def = self.get_trait_def(trait_id);
575 let index = ty::associated_type_parameter_index(self.tcx,
578 ty::mk_param(self.tcx, subst::TypeSpace, index, associated_type_id)
582 impl<'a, 'tcx, 'v> Visitor<'v> for Context<'a, 'tcx> {
583 fn visit_item(&mut self, it: &ast::Item) {
584 self.with_lint_attrs(it.attrs.as_slice(), |cx| {
585 run_lints!(cx, check_item, it);
586 cx.visit_ids(|v| v.visit_item(it));
587 visit::walk_item(cx, it);
591 fn visit_foreign_item(&mut self, it: &ast::ForeignItem) {
592 self.with_lint_attrs(it.attrs.as_slice(), |cx| {
593 run_lints!(cx, check_foreign_item, it);
594 visit::walk_foreign_item(cx, it);
598 fn visit_view_item(&mut self, i: &ast::ViewItem) {
599 self.with_lint_attrs(i.attrs.as_slice(), |cx| {
600 run_lints!(cx, check_view_item, i);
601 cx.visit_ids(|v| v.visit_view_item(i));
602 visit::walk_view_item(cx, i);
606 fn visit_pat(&mut self, p: &ast::Pat) {
607 run_lints!(self, check_pat, p);
608 visit::walk_pat(self, p);
611 fn visit_expr(&mut self, e: &ast::Expr) {
612 run_lints!(self, check_expr, e);
613 visit::walk_expr(self, e);
616 fn visit_stmt(&mut self, s: &ast::Stmt) {
617 run_lints!(self, check_stmt, s);
618 visit::walk_stmt(self, s);
621 fn visit_fn(&mut self, fk: FnKind<'v>, decl: &'v ast::FnDecl,
622 body: &'v ast::Block, span: Span, id: ast::NodeId) {
624 visit::FkMethod(_, _, m) => {
625 self.with_lint_attrs(m.attrs.as_slice(), |cx| {
626 run_lints!(cx, check_fn, fk, decl, body, span, id);
628 v.visit_fn(fk, decl, body, span, id);
630 visit::walk_fn(cx, fk, decl, body, span);
634 run_lints!(self, check_fn, fk, decl, body, span, id);
635 visit::walk_fn(self, fk, decl, body, span);
640 fn visit_ty_method(&mut self, t: &ast::TypeMethod) {
641 self.with_lint_attrs(t.attrs.as_slice(), |cx| {
642 run_lints!(cx, check_ty_method, t);
643 visit::walk_ty_method(cx, t);
647 fn visit_struct_def(&mut self,
652 run_lints!(self, check_struct_def, s, ident, g, id);
653 visit::walk_struct_def(self, s);
654 run_lints!(self, check_struct_def_post, s, ident, g, id);
657 fn visit_struct_field(&mut self, s: &ast::StructField) {
658 self.with_lint_attrs(s.node.attrs.as_slice(), |cx| {
659 run_lints!(cx, check_struct_field, s);
660 visit::walk_struct_field(cx, s);
664 fn visit_variant(&mut self, v: &ast::Variant, g: &ast::Generics) {
665 self.with_lint_attrs(v.node.attrs.as_slice(), |cx| {
666 run_lints!(cx, check_variant, v, g);
667 visit::walk_variant(cx, v, g);
668 run_lints!(cx, check_variant_post, v, g);
672 // FIXME(#10894) should continue recursing
673 fn visit_ty(&mut self, t: &ast::Ty) {
674 run_lints!(self, check_ty, t);
677 fn visit_ident(&mut self, sp: Span, id: ast::Ident) {
678 run_lints!(self, check_ident, sp, id);
681 fn visit_mod(&mut self, m: &ast::Mod, s: Span, n: ast::NodeId) {
682 run_lints!(self, check_mod, m, s, n);
683 visit::walk_mod(self, m);
686 fn visit_local(&mut self, l: &ast::Local) {
687 run_lints!(self, check_local, l);
688 visit::walk_local(self, l);
691 fn visit_block(&mut self, b: &ast::Block) {
692 run_lints!(self, check_block, b);
693 visit::walk_block(self, b);
696 fn visit_arm(&mut self, a: &ast::Arm) {
697 run_lints!(self, check_arm, a);
698 visit::walk_arm(self, a);
701 fn visit_decl(&mut self, d: &ast::Decl) {
702 run_lints!(self, check_decl, d);
703 visit::walk_decl(self, d);
706 fn visit_expr_post(&mut self, e: &ast::Expr) {
707 run_lints!(self, check_expr_post, e);
710 fn visit_generics(&mut self, g: &ast::Generics) {
711 run_lints!(self, check_generics, g);
712 visit::walk_generics(self, g);
715 fn visit_trait_item(&mut self, m: &ast::TraitItem) {
716 run_lints!(self, check_trait_method, m);
717 visit::walk_trait_item(self, m);
720 fn visit_opt_lifetime_ref(&mut self, sp: Span, lt: &Option<ast::Lifetime>) {
721 run_lints!(self, check_opt_lifetime_ref, sp, lt);
724 fn visit_lifetime_ref(&mut self, lt: &ast::Lifetime) {
725 run_lints!(self, check_lifetime_ref, lt);
728 fn visit_lifetime_def(&mut self, lt: &ast::LifetimeDef) {
729 run_lints!(self, check_lifetime_def, lt);
732 fn visit_explicit_self(&mut self, es: &ast::ExplicitSelf) {
733 run_lints!(self, check_explicit_self, es);
734 visit::walk_explicit_self(self, es);
737 fn visit_mac(&mut self, mac: &ast::Mac) {
738 run_lints!(self, check_mac, mac);
739 visit::walk_mac(self, mac);
742 fn visit_path(&mut self, p: &ast::Path, id: ast::NodeId) {
743 run_lints!(self, check_path, p, id);
744 visit::walk_path(self, p);
747 fn visit_attribute(&mut self, attr: &ast::Attribute) {
748 run_lints!(self, check_attribute, attr);
752 // Output any lints that were previously added to the session.
753 impl<'a, 'tcx> IdVisitingOperation for Context<'a, 'tcx> {
754 fn visit_id(&mut self, id: ast::NodeId) {
755 match self.tcx.sess.lints.borrow_mut().remove(&id) {
758 for (lint_id, span, msg) in lints.into_iter() {
759 self.span_lint(lint_id.lint, span, msg.as_slice())
766 // This lint pass is defined here because it touches parts of the `Context`
767 // that we don't want to expose. It records the lint level at certain AST
768 // nodes, so that the variant size difference check in trans can call
771 struct GatherNodeLevels;
773 impl LintPass for GatherNodeLevels {
774 fn get_lints(&self) -> LintArray {
778 fn check_item(&mut self, cx: &Context, it: &ast::Item) {
780 ast::ItemEnum(..) => {
781 let lint_id = LintId::of(builtin::VARIANT_SIZE_DIFFERENCES);
782 let lvlsrc = cx.lints.get_level_source(lint_id);
784 (lvl, _) if lvl != Allow => {
785 cx.node_levels.borrow_mut()
786 .insert((it.id, lint_id), lvlsrc);
796 /// Perform lint checking on a crate.
798 /// Consumes the `lint_store` field of the `Session`.
799 pub fn check_crate(tcx: &ty::ctxt,
800 exported_items: &ExportedItems) {
801 let krate = tcx.map.krate();
802 let mut cx = Context::new(tcx, krate, exported_items);
804 // Visit the whole crate.
805 cx.with_lint_attrs(krate.attrs.as_slice(), |cx| {
806 cx.visit_id(ast::CRATE_NODE_ID);
808 v.visited_outermost = true;
809 visit::walk_crate(v, krate);
812 // since the root module isn't visited as an item (because it isn't an
813 // item), warn for it here.
814 run_lints!(cx, check_crate, krate);
816 visit::walk_crate(cx, krate);
819 // If we missed any lints added to the session, then there's a bug somewhere
820 // in the iteration code.
821 for (id, v) in tcx.sess.lints.borrow().iter() {
822 for &(lint, span, ref msg) in v.iter() {
823 tcx.sess.span_bug(span,
824 format!("unprocessed lint {} at {}: {}",
825 lint.as_str(), tcx.map.node_to_string(*id), *msg).as_slice())
829 tcx.sess.abort_if_errors();
830 *tcx.node_lint_levels.borrow_mut() = cx.node_levels.into_inner();