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use rustc::hir::def::Def;
use rustc::hir::def_id::DefId;
use rustc::cfg;
use rustc::ty::subst::Substs;
use rustc::ty::{self, Ty, TyCtxt};
use rustc::traits::{self, Reveal};
use rustc::hir::map as hir_map;
use util::nodemap::NodeSet;
use lint::{Level, LateContext, LintContext, LintArray};
use lint::{LintPass, LateLintPass, EarlyLintPass, EarlyContext};
use std::collections::HashSet;
use syntax::ast;
use syntax::attr;
use syntax::feature_gate::{AttributeGate, AttributeType, Stability, deprecated_attributes};
use syntax_pos::Span;
use rustc::hir::{self, PatKind};
use rustc::hir::intravisit::FnKind;
use bad_style::{MethodLateContext, method_context};
pub use lint::builtin::*;
declare_lint! {
WHILE_TRUE,
Warn,
"suggest using `loop { }` instead of `while true { }`"
}
#[derive(Copy, Clone)]
pub struct WhileTrue;
impl LintPass for WhileTrue {
fn get_lints(&self) -> LintArray {
lint_array!(WHILE_TRUE)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for WhileTrue {
fn check_expr(&mut self, cx: &LateContext, e: &hir::Expr) {
if let hir::ExprWhile(ref cond, ..) = e.node {
if let hir::ExprLit(ref lit) = cond.node {
if let ast::LitKind::Bool(true) = lit.node {
cx.span_lint(WHILE_TRUE,
e.span,
"denote infinite loops with loop { ... }");
}
}
}
}
}
declare_lint! {
BOX_POINTERS,
Allow,
"use of owned (Box type) heap memory"
}
#[derive(Copy, Clone)]
pub struct BoxPointers;
impl BoxPointers {
fn check_heap_type<'a, 'tcx>(&self, cx: &LateContext, span: Span, ty: Ty) {
for leaf_ty in ty.walk() {
if leaf_ty.is_box() {
let m = format!("type uses owned (Box type) pointers: {}", ty);
cx.span_lint(BOX_POINTERS, span, &m);
}
}
}
}
impl LintPass for BoxPointers {
fn get_lints(&self) -> LintArray {
lint_array!(BOX_POINTERS)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for BoxPointers {
fn check_item(&mut self, cx: &LateContext, it: &hir::Item) {
match it.node {
hir::ItemFn(..) |
hir::ItemTy(..) |
hir::ItemEnum(..) |
hir::ItemStruct(..) |
hir::ItemUnion(..) => {
let def_id = cx.tcx.hir.local_def_id(it.id);
self.check_heap_type(cx, it.span, cx.tcx.item_type(def_id))
}
_ => ()
}
match it.node {
hir::ItemStruct(ref struct_def, _) |
hir::ItemUnion(ref struct_def, _) => {
for struct_field in struct_def.fields() {
let def_id = cx.tcx.hir.local_def_id(struct_field.id);
self.check_heap_type(cx, struct_field.span,
cx.tcx.item_type(def_id));
}
}
_ => (),
}
}
fn check_expr(&mut self, cx: &LateContext, e: &hir::Expr) {
let ty = cx.tables.node_id_to_type(e.id);
self.check_heap_type(cx, e.span, ty);
}
}
declare_lint! {
NON_SHORTHAND_FIELD_PATTERNS,
Warn,
"using `Struct { x: x }` instead of `Struct { x }`"
}
#[derive(Copy, Clone)]
pub struct NonShorthandFieldPatterns;
impl LintPass for NonShorthandFieldPatterns {
fn get_lints(&self) -> LintArray {
lint_array!(NON_SHORTHAND_FIELD_PATTERNS)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for NonShorthandFieldPatterns {
fn check_pat(&mut self, cx: &LateContext, pat: &hir::Pat) {
if let PatKind::Struct(_, ref field_pats, _) = pat.node {
for fieldpat in field_pats {
if fieldpat.node.is_shorthand {
continue;
}
if let PatKind::Binding(_, _, ident, None) = fieldpat.node.pat.node {
if ident.node == fieldpat.node.name {
cx.span_lint(NON_SHORTHAND_FIELD_PATTERNS,
fieldpat.span,
&format!("the `{}:` in this pattern is redundant and can \
be removed",
ident.node))
}
}
}
}
}
}
declare_lint! {
UNSAFE_CODE,
Allow,
"usage of `unsafe` code"
}
#[derive(Copy, Clone)]
pub struct UnsafeCode;
impl LintPass for UnsafeCode {
fn get_lints(&self) -> LintArray {
lint_array!(UNSAFE_CODE)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnsafeCode {
fn check_expr(&mut self, cx: &LateContext, e: &hir::Expr) {
if let hir::ExprBlock(ref blk) = e.node {
if blk.rules == hir::UnsafeBlock(hir::UserProvided) {
cx.span_lint(UNSAFE_CODE, blk.span, "usage of an `unsafe` block");
}
}
}
fn check_item(&mut self, cx: &LateContext, it: &hir::Item) {
match it.node {
hir::ItemTrait(hir::Unsafety::Unsafe, ..) => {
cx.span_lint(UNSAFE_CODE, it.span, "declaration of an `unsafe` trait")
}
hir::ItemImpl(hir::Unsafety::Unsafe, ..) => {
cx.span_lint(UNSAFE_CODE, it.span, "implementation of an `unsafe` trait")
}
_ => return,
}
}
fn check_fn(&mut self,
cx: &LateContext,
fk: FnKind<'tcx>,
_: &hir::FnDecl,
_: &hir::Body,
span: Span,
_: ast::NodeId) {
match fk {
FnKind::ItemFn(_, _, hir::Unsafety::Unsafe, ..) => {
cx.span_lint(UNSAFE_CODE, span, "declaration of an `unsafe` function")
}
FnKind::Method(_, sig, ..) => {
if sig.unsafety == hir::Unsafety::Unsafe {
cx.span_lint(UNSAFE_CODE, span, "implementation of an `unsafe` method")
}
}
_ => (),
}
}
fn check_trait_item(&mut self, cx: &LateContext, item: &hir::TraitItem) {
if let hir::TraitItemKind::Method(ref sig, hir::TraitMethod::Required(_)) = item.node {
if sig.unsafety == hir::Unsafety::Unsafe {
cx.span_lint(UNSAFE_CODE,
item.span,
"declaration of an `unsafe` method")
}
}
}
}
declare_lint! {
MISSING_DOCS,
Allow,
"detects missing documentation for public members"
}
pub struct MissingDoc {
struct_def_stack: Vec<ast::NodeId>,
in_variant: bool,
doc_hidden_stack: Vec<bool>,
private_traits: HashSet<ast::NodeId>,
}
impl MissingDoc {
pub fn new() -> MissingDoc {
MissingDoc {
struct_def_stack: vec![],
in_variant: false,
doc_hidden_stack: vec![false],
private_traits: HashSet::new(),
}
}
fn doc_hidden(&self) -> bool {
*self.doc_hidden_stack.last().expect("empty doc_hidden_stack")
}
fn check_missing_docs_attrs(&self,
cx: &LateContext,
id: Option<ast::NodeId>,
attrs: &[ast::Attribute],
sp: Span,
desc: &'static str) {
if cx.sess().opts.test {
return;
}
if self.doc_hidden() {
return;
}
if let Some(id) = id {
if !cx.access_levels.is_exported(id) {
return;
}
}
let has_doc = attrs.iter().any(|a| a.is_value_str() && a.name() == "doc");
if !has_doc {
cx.span_lint(MISSING_DOCS,
sp,
&format!("missing documentation for {}", desc));
}
}
}
impl LintPass for MissingDoc {
fn get_lints(&self) -> LintArray {
lint_array!(MISSING_DOCS)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MissingDoc {
fn enter_lint_attrs(&mut self, _: &LateContext, attrs: &[ast::Attribute]) {
let doc_hidden = self.doc_hidden() ||
attrs.iter().any(|attr| {
attr.check_name("doc") &&
match attr.meta_item_list() {
None => false,
Some(l) => attr::list_contains_name(&l[..], "hidden"),
}
});
self.doc_hidden_stack.push(doc_hidden);
}
fn exit_lint_attrs(&mut self, _: &LateContext, _attrs: &[ast::Attribute]) {
self.doc_hidden_stack.pop().expect("empty doc_hidden_stack");
}
fn check_struct_def(&mut self,
_: &LateContext,
_: &hir::VariantData,
_: ast::Name,
_: &hir::Generics,
item_id: ast::NodeId) {
self.struct_def_stack.push(item_id);
}
fn check_struct_def_post(&mut self,
_: &LateContext,
_: &hir::VariantData,
_: ast::Name,
_: &hir::Generics,
item_id: ast::NodeId) {
let popped = self.struct_def_stack.pop().expect("empty struct_def_stack");
assert!(popped == item_id);
}
fn check_crate(&mut self, cx: &LateContext, krate: &hir::Crate) {
self.check_missing_docs_attrs(cx, None, &krate.attrs, krate.span, "crate");
}
fn check_item(&mut self, cx: &LateContext, it: &hir::Item) {
let desc = match it.node {
hir::ItemFn(..) => "a function",
hir::ItemMod(..) => "a module",
hir::ItemEnum(..) => "an enum",
hir::ItemStruct(..) => "a struct",
hir::ItemUnion(..) => "a union",
hir::ItemTrait(.., ref trait_item_refs) => {
if it.vis == hir::Visibility::Inherited {
self.private_traits.insert(it.id);
for trait_item_ref in trait_item_refs {
self.private_traits.insert(trait_item_ref.id.node_id);
}
return;
}
"a trait"
}
hir::ItemTy(..) => "a type alias",
hir::ItemImpl(.., Some(ref trait_ref), _, ref impl_item_refs) => {
let real_trait = trait_ref.path.def.def_id();
if let Some(node_id) = cx.tcx.hir.as_local_node_id(real_trait) {
match cx.tcx.hir.find(node_id) {
Some(hir_map::NodeItem(item)) => {
if item.vis == hir::Visibility::Inherited {
for impl_item_ref in impl_item_refs {
self.private_traits.insert(impl_item_ref.id.node_id);
}
}
}
_ => {}
}
}
return;
}
hir::ItemConst(..) => "a constant",
hir::ItemStatic(..) => "a static",
_ => return,
};
self.check_missing_docs_attrs(cx, Some(it.id), &it.attrs, it.span, desc);
}
fn check_trait_item(&mut self, cx: &LateContext, trait_item: &hir::TraitItem) {
if self.private_traits.contains(&trait_item.id) {
return;
}
let desc = match trait_item.node {
hir::TraitItemKind::Const(..) => "an associated constant",
hir::TraitItemKind::Method(..) => "a trait method",
hir::TraitItemKind::Type(..) => "an associated type",
};
self.check_missing_docs_attrs(cx,
Some(trait_item.id),
&trait_item.attrs,
trait_item.span,
desc);
}
fn check_impl_item(&mut self, cx: &LateContext, impl_item: &hir::ImplItem) {
if method_context(cx, impl_item.id, impl_item.span) == MethodLateContext::TraitImpl {
return;
}
let desc = match impl_item.node {
hir::ImplItemKind::Const(..) => "an associated constant",
hir::ImplItemKind::Method(..) => "a method",
hir::ImplItemKind::Type(_) => "an associated type",
};
self.check_missing_docs_attrs(cx,
Some(impl_item.id),
&impl_item.attrs,
impl_item.span,
desc);
}
fn check_struct_field(&mut self, cx: &LateContext, sf: &hir::StructField) {
if !sf.is_positional() {
if sf.vis == hir::Public || self.in_variant {
let cur_struct_def = *self.struct_def_stack
.last()
.expect("empty struct_def_stack");
self.check_missing_docs_attrs(cx,
Some(cur_struct_def),
&sf.attrs,
sf.span,
"a struct field")
}
}
}
fn check_variant(&mut self, cx: &LateContext, v: &hir::Variant, _: &hir::Generics) {
self.check_missing_docs_attrs(cx,
Some(v.node.data.id()),
&v.node.attrs,
v.span,
"a variant");
assert!(!self.in_variant);
self.in_variant = true;
}
fn check_variant_post(&mut self, _: &LateContext, _: &hir::Variant, _: &hir::Generics) {
assert!(self.in_variant);
self.in_variant = false;
}
}
declare_lint! {
pub MISSING_COPY_IMPLEMENTATIONS,
Allow,
"detects potentially-forgotten implementations of `Copy`"
}
#[derive(Copy, Clone)]
pub struct MissingCopyImplementations;
impl LintPass for MissingCopyImplementations {
fn get_lints(&self) -> LintArray {
lint_array!(MISSING_COPY_IMPLEMENTATIONS)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MissingCopyImplementations {
fn check_item(&mut self, cx: &LateContext, item: &hir::Item) {
if !cx.access_levels.is_reachable(item.id) {
return;
}
let (def, ty) = match item.node {
hir::ItemStruct(_, ref ast_generics) => {
if ast_generics.is_parameterized() {
return;
}
let def = cx.tcx.lookup_adt_def(cx.tcx.hir.local_def_id(item.id));
(def, cx.tcx.mk_adt(def, cx.tcx.intern_substs(&[])))
}
hir::ItemUnion(_, ref ast_generics) => {
if ast_generics.is_parameterized() {
return;
}
let def = cx.tcx.lookup_adt_def(cx.tcx.hir.local_def_id(item.id));
(def, cx.tcx.mk_adt(def, cx.tcx.intern_substs(&[])))
}
hir::ItemEnum(_, ref ast_generics) => {
if ast_generics.is_parameterized() {
return;
}
let def = cx.tcx.lookup_adt_def(cx.tcx.hir.local_def_id(item.id));
(def, cx.tcx.mk_adt(def, cx.tcx.intern_substs(&[])))
}
_ => return,
};
if def.has_dtor(cx.tcx) {
return;
}
let parameter_environment = cx.tcx.empty_parameter_environment();
if !ty.moves_by_default(cx.tcx, ¶meter_environment, item.span) {
return;
}
if parameter_environment.can_type_implement_copy(cx.tcx, ty, item.span).is_ok() {
cx.span_lint(MISSING_COPY_IMPLEMENTATIONS,
item.span,
"type could implement `Copy`; consider adding `impl \
Copy`")
}
}
}
declare_lint! {
MISSING_DEBUG_IMPLEMENTATIONS,
Allow,
"detects missing implementations of fmt::Debug"
}
pub struct MissingDebugImplementations {
impling_types: Option<NodeSet>,
}
impl MissingDebugImplementations {
pub fn new() -> MissingDebugImplementations {
MissingDebugImplementations { impling_types: None }
}
}
impl LintPass for MissingDebugImplementations {
fn get_lints(&self) -> LintArray {
lint_array!(MISSING_DEBUG_IMPLEMENTATIONS)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MissingDebugImplementations {
fn check_item(&mut self, cx: &LateContext, item: &hir::Item) {
if !cx.access_levels.is_reachable(item.id) {
return;
}
match item.node {
hir::ItemStruct(..) |
hir::ItemUnion(..) |
hir::ItemEnum(..) => {}
_ => return,
}
let debug = match cx.tcx.lang_items.debug_trait() {
Some(debug) => debug,
None => return,
};
if self.impling_types.is_none() {
let debug_def = cx.tcx.lookup_trait_def(debug);
let mut impls = NodeSet();
debug_def.for_each_impl(cx.tcx, |d| {
if let Some(ty_def) = cx.tcx.item_type(d).ty_to_def_id() {
if let Some(node_id) = cx.tcx.hir.as_local_node_id(ty_def) {
impls.insert(node_id);
}
}
});
self.impling_types = Some(impls);
debug!("{:?}", self.impling_types);
}
if !self.impling_types.as_ref().unwrap().contains(&item.id) {
cx.span_lint(MISSING_DEBUG_IMPLEMENTATIONS,
item.span,
"type does not implement `fmt::Debug`; consider adding #[derive(Debug)] \
or a manual implementation")
}
}
}
declare_lint! {
DEPRECATED_ATTR,
Warn,
"detects use of deprecated attributes"
}
#[derive(Clone)]
pub struct DeprecatedAttr {
depr_attrs: Vec<&'static (&'static str, AttributeType, AttributeGate)>,
}
impl DeprecatedAttr {
pub fn new() -> DeprecatedAttr {
DeprecatedAttr {
depr_attrs: deprecated_attributes(),
}
}
}
impl LintPass for DeprecatedAttr {
fn get_lints(&self) -> LintArray {
lint_array!(DEPRECATED_ATTR)
}
}
impl EarlyLintPass for DeprecatedAttr {
fn check_attribute(&mut self, cx: &EarlyContext, attr: &ast::Attribute) {
let name = attr.name();
for &&(n, _, ref g) in &self.depr_attrs {
if name == n {
if let &AttributeGate::Gated(Stability::Deprecated(link),
ref name,
ref reason,
_) = g {
cx.span_lint(DEPRECATED,
attr.span,
&format!("use of deprecated attribute `{}`: {}. See {}",
name, reason, link));
}
return;
}
}
}
}
declare_lint! {
pub UNCONDITIONAL_RECURSION,
Warn,
"functions that cannot return without calling themselves"
}
#[derive(Copy, Clone)]
pub struct UnconditionalRecursion;
impl LintPass for UnconditionalRecursion {
fn get_lints(&self) -> LintArray {
lint_array![UNCONDITIONAL_RECURSION]
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnconditionalRecursion {
fn check_fn(&mut self,
cx: &LateContext,
fn_kind: FnKind,
_: &hir::FnDecl,
body: &hir::Body,
sp: Span,
id: ast::NodeId) {
let method = match fn_kind {
FnKind::ItemFn(..) => None,
FnKind::Method(..) => {
Some(cx.tcx.associated_item(cx.tcx.hir.local_def_id(id)))
}
FnKind::Closure(_) => return,
};
let cfg = cfg::CFG::new(cx.tcx, &body);
let mut work_queue = vec![cfg.entry];
let mut reached_exit_without_self_call = false;
let mut self_call_spans = vec![];
let mut visited = HashSet::new();
while let Some(idx) = work_queue.pop() {
if idx == cfg.exit {
reached_exit_without_self_call = true;
break;
}
let cfg_id = idx.node_id();
if visited.contains(&cfg_id) {
continue;
}
visited.insert(cfg_id);
let node_id = cfg.graph.node_data(idx).id();
let self_recursive = if node_id != ast::DUMMY_NODE_ID {
match method {
Some(ref method) => expr_refers_to_this_method(cx, method, node_id),
None => expr_refers_to_this_fn(cx, id, node_id),
}
} else {
false
};
if self_recursive {
self_call_spans.push(cx.tcx.hir.span(node_id));
continue;
}
for (_, edge) in cfg.graph.outgoing_edges(idx) {
let target_idx = edge.target();
let target_cfg_id = target_idx.node_id();
if !visited.contains(&target_cfg_id) {
work_queue.push(target_idx)
}
}
}
if !reached_exit_without_self_call && !self_call_spans.is_empty() {
let mut db = cx.struct_span_lint(UNCONDITIONAL_RECURSION,
sp,
"function cannot return without recurring");
if cx.current_level(UNCONDITIONAL_RECURSION) != Level::Allow {
for call in &self_call_spans {
db.span_note(*call, "recursive call site");
}
db.help("a `loop` may express intention \
better if this is on purpose");
}
db.emit();
}
return;
fn expr_refers_to_this_fn(cx: &LateContext, fn_id: ast::NodeId, id: ast::NodeId) -> bool {
match cx.tcx.hir.get(id) {
hir_map::NodeExpr(&hir::Expr { node: hir::ExprCall(ref callee, _), .. }) => {
let def = if let hir::ExprPath(ref qpath) = callee.node {
cx.tables.qpath_def(qpath, callee.id)
} else {
return false;
};
def.def_id() == cx.tcx.hir.local_def_id(fn_id)
}
_ => false,
}
}
fn expr_refers_to_this_method(cx: &LateContext,
method: &ty::AssociatedItem,
id: ast::NodeId)
-> bool {
use rustc::ty::adjustment::*;
let opt_m = cx.tables.method_map.get(&ty::MethodCall::expr(id)).cloned();
if let Some(m) = opt_m {
if method_call_refers_to_method(cx.tcx, method, m.def_id, m.substs, id) {
return true;
}
}
let opt_adj = cx.tables.adjustments.get(&id).cloned();
if let Some(Adjustment { kind: Adjust::DerefRef { autoderefs, .. }, .. }) = opt_adj {
for i in 0..autoderefs {
let method_call = ty::MethodCall::autoderef(id, i as u32);
if let Some(m) = cx.tables.method_map.get(&method_call).cloned() {
if method_call_refers_to_method(cx.tcx, method, m.def_id, m.substs, id) {
return true;
}
}
}
}
match cx.tcx.hir.get(id) {
hir_map::NodeExpr(&hir::Expr { node: hir::ExprCall(ref callee, _), .. }) => {
let def = if let hir::ExprPath(ref qpath) = callee.node {
cx.tables.qpath_def(qpath, callee.id)
} else {
return false;
};
match def {
Def::Method(def_id) => {
let substs = cx.tables.node_id_item_substs(callee.id)
.unwrap_or_else(|| cx.tcx.intern_substs(&[]));
method_call_refers_to_method(
cx.tcx, method, def_id, substs, id)
}
_ => false,
}
}
_ => false,
}
}
fn method_call_refers_to_method<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
method: &ty::AssociatedItem,
callee_id: DefId,
callee_substs: &Substs<'tcx>,
expr_id: ast::NodeId)
-> bool {
let callee_item = tcx.associated_item(callee_id);
match callee_item.container {
ty::ImplContainer(_) => callee_id == method.def_id,
ty::TraitContainer(trait_def_id) => {
let trait_ref = ty::TraitRef::from_method(tcx, trait_def_id, callee_substs);
let trait_ref = ty::Binder(trait_ref);
let span = tcx.hir.span(expr_id);
let obligation =
traits::Obligation::new(traits::ObligationCause::misc(span, expr_id),
trait_ref.to_poly_trait_predicate());
let node_id = tcx.hir.as_local_node_id(method.def_id).unwrap();
let param_env = ty::ParameterEnvironment::for_item(tcx, node_id);
tcx.infer_ctxt(param_env, Reveal::UserFacing).enter(|infcx| {
let mut selcx = traits::SelectionContext::new(&infcx);
match selcx.select(&obligation) {
Ok(Some(traits::VtableParam(_))) => {
let on_self = trait_ref.self_ty().is_self();
on_self && callee_id == method.def_id
}
Ok(Some(traits::VtableImpl(vtable_impl))) => {
let container = ty::ImplContainer(vtable_impl.impl_def_id);
container == method.container && callee_item.name == method.name
}
_ => false,
}
})
}
}
}
}
}
declare_lint! {
PLUGIN_AS_LIBRARY,
Warn,
"compiler plugin used as ordinary library in non-plugin crate"
}
#[derive(Copy, Clone)]
pub struct PluginAsLibrary;
impl LintPass for PluginAsLibrary {
fn get_lints(&self) -> LintArray {
lint_array![PLUGIN_AS_LIBRARY]
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for PluginAsLibrary {
fn check_item(&mut self, cx: &LateContext, it: &hir::Item) {
if cx.sess().plugin_registrar_fn.get().is_some() {
return;
}
match it.node {
hir::ItemExternCrate(..) => (),
_ => return,
};
let prfn = match cx.sess().cstore.extern_mod_stmt_cnum(it.id) {
Some(cnum) => cx.sess().cstore.plugin_registrar_fn(cnum),
None => {
return;
}
};
if prfn.is_some() {
cx.span_lint(PLUGIN_AS_LIBRARY,
it.span,
"compiler plugin used as an ordinary library");
}
}
}
declare_lint! {
PRIVATE_NO_MANGLE_FNS,
Warn,
"functions marked #[no_mangle] should be exported"
}
declare_lint! {
PRIVATE_NO_MANGLE_STATICS,
Warn,
"statics marked #[no_mangle] should be exported"
}
declare_lint! {
NO_MANGLE_CONST_ITEMS,
Deny,
"const items will not have their symbols exported"
}
declare_lint! {
NO_MANGLE_GENERIC_ITEMS,
Warn,
"generic items must be mangled"
}
#[derive(Copy, Clone)]
pub struct InvalidNoMangleItems;
impl LintPass for InvalidNoMangleItems {
fn get_lints(&self) -> LintArray {
lint_array!(PRIVATE_NO_MANGLE_FNS,
PRIVATE_NO_MANGLE_STATICS,
NO_MANGLE_CONST_ITEMS,
NO_MANGLE_GENERIC_ITEMS)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for InvalidNoMangleItems {
fn check_item(&mut self, cx: &LateContext, it: &hir::Item) {
match it.node {
hir::ItemFn(.., ref generics, _) => {
if attr::contains_name(&it.attrs, "no_mangle") {
if !cx.access_levels.is_reachable(it.id) {
let msg = format!("function {} is marked #[no_mangle], but not exported",
it.name);
cx.span_lint(PRIVATE_NO_MANGLE_FNS, it.span, &msg);
}
if generics.is_parameterized() {
cx.span_lint(NO_MANGLE_GENERIC_ITEMS,
it.span,
"generic functions must be mangled");
}
}
}
hir::ItemStatic(..) => {
if attr::contains_name(&it.attrs, "no_mangle") &&
!cx.access_levels.is_reachable(it.id) {
let msg = format!("static {} is marked #[no_mangle], but not exported",
it.name);
cx.span_lint(PRIVATE_NO_MANGLE_STATICS, it.span, &msg);
}
}
hir::ItemConst(..) => {
if attr::contains_name(&it.attrs, "no_mangle") {
let msg = "const items should never be #[no_mangle], consider instead using \
`pub static`";
cx.span_lint(NO_MANGLE_CONST_ITEMS, it.span, msg);
}
}
_ => {}
}
}
}
#[derive(Clone, Copy)]
pub struct MutableTransmutes;
declare_lint! {
MUTABLE_TRANSMUTES,
Deny,
"mutating transmuted &mut T from &T may cause undefined behavior"
}
impl LintPass for MutableTransmutes {
fn get_lints(&self) -> LintArray {
lint_array!(MUTABLE_TRANSMUTES)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MutableTransmutes {
fn check_expr(&mut self, cx: &LateContext, expr: &hir::Expr) {
use syntax::abi::Abi::RustIntrinsic;
let msg = "mutating transmuted &mut T from &T may cause undefined behavior, \
consider instead using an UnsafeCell";
match get_transmute_from_to(cx, expr) {
Some((&ty::TyRef(_, from_mt), &ty::TyRef(_, to_mt))) => {
if to_mt.mutbl == hir::Mutability::MutMutable &&
from_mt.mutbl == hir::Mutability::MutImmutable {
cx.span_lint(MUTABLE_TRANSMUTES, expr.span, msg);
}
}
_ => (),
}
fn get_transmute_from_to<'a, 'tcx>
(cx: &LateContext<'a, 'tcx>,
expr: &hir::Expr)
-> Option<(&'tcx ty::TypeVariants<'tcx>, &'tcx ty::TypeVariants<'tcx>)> {
let def = if let hir::ExprPath(ref qpath) = expr.node {
cx.tables.qpath_def(qpath, expr.id)
} else {
return None;
};
if let Def::Fn(did) = def {
if !def_id_is_transmute(cx, did) {
return None;
}
let typ = cx.tables.node_id_to_type(expr.id);
match typ.sty {
ty::TyFnDef(.., bare_fn) if bare_fn.abi() == RustIntrinsic => {
let from = bare_fn.inputs().skip_binder()[0];
let to = *bare_fn.output().skip_binder();
return Some((&from.sty, &to.sty));
}
_ => (),
}
}
None
}
fn def_id_is_transmute(cx: &LateContext, def_id: DefId) -> bool {
match cx.tcx.item_type(def_id).sty {
ty::TyFnDef(.., bfty) if bfty.abi() == RustIntrinsic => (),
_ => return false,
}
cx.tcx.item_name(def_id) == "transmute"
}
}
}
#[derive(Copy, Clone)]
pub struct UnstableFeatures;
declare_lint! {
UNSTABLE_FEATURES,
Allow,
"enabling unstable features (deprecated. do not use)"
}
impl LintPass for UnstableFeatures {
fn get_lints(&self) -> LintArray {
lint_array!(UNSTABLE_FEATURES)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnstableFeatures {
fn check_attribute(&mut self, ctx: &LateContext, attr: &ast::Attribute) {
if attr.meta().check_name("feature") {
if let Some(items) = attr.meta().meta_item_list() {
for item in items {
ctx.span_lint(UNSTABLE_FEATURES, item.span(), "unstable feature");
}
}
}
}
}
pub struct UnionsWithDropFields;
declare_lint! {
UNIONS_WITH_DROP_FIELDS,
Warn,
"use of unions that contain fields with possibly non-trivial drop code"
}
impl LintPass for UnionsWithDropFields {
fn get_lints(&self) -> LintArray {
lint_array!(UNIONS_WITH_DROP_FIELDS)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnionsWithDropFields {
fn check_item(&mut self, ctx: &LateContext, item: &hir::Item) {
if let hir::ItemUnion(ref vdata, _) = item.node {
let param_env = &ty::ParameterEnvironment::for_item(ctx.tcx, item.id);
for field in vdata.fields() {
let field_ty = ctx.tcx.item_type(ctx.tcx.hir.local_def_id(field.id));
if ctx.tcx.type_needs_drop_given_env(field_ty, param_env) {
ctx.span_lint(UNIONS_WITH_DROP_FIELDS,
field.span,
"union contains a field with possibly non-trivial drop code, \
drop code of union fields is ignored when dropping the union");
return;
}
}
}
}
}