948 lines
37 KiB
Rust
948 lines
37 KiB
Rust
//! A pass that annotates every item and method with its stability level,
|
|
//! propagating default levels lexically from parent to children ast nodes.
|
|
|
|
use rustc_attr::{self as attr, ConstStability, Stability};
|
|
use rustc_data_structures::fx::{FxHashSet, FxIndexMap};
|
|
use rustc_errors::struct_span_err;
|
|
use rustc_hir as hir;
|
|
use rustc_hir::def::{DefKind, Res};
|
|
use rustc_hir::def_id::{LocalDefId, CRATE_DEF_ID};
|
|
use rustc_hir::hir_id::CRATE_HIR_ID;
|
|
use rustc_hir::intravisit::{self, Visitor};
|
|
use rustc_hir::{FieldDef, Generics, HirId, Item, TraitRef, Ty, TyKind, Variant};
|
|
use rustc_middle::hir::nested_filter;
|
|
use rustc_middle::middle::privacy::AccessLevels;
|
|
use rustc_middle::middle::stability::{DeprecationEntry, Index};
|
|
use rustc_middle::ty::{self, query::Providers, TyCtxt};
|
|
use rustc_session::lint;
|
|
use rustc_session::lint::builtin::{INEFFECTIVE_UNSTABLE_TRAIT_IMPL, USELESS_DEPRECATED};
|
|
use rustc_session::parse::feature_err;
|
|
use rustc_session::Session;
|
|
use rustc_span::symbol::{sym, Symbol};
|
|
use rustc_span::{Span, DUMMY_SP};
|
|
use rustc_target::spec::abi::Abi;
|
|
|
|
use std::cmp::Ordering;
|
|
use std::iter;
|
|
use std::mem::replace;
|
|
use std::num::NonZeroU32;
|
|
|
|
#[derive(PartialEq)]
|
|
enum AnnotationKind {
|
|
// Annotation is required if not inherited from unstable parents
|
|
Required,
|
|
// Annotation is useless, reject it
|
|
Prohibited,
|
|
// Deprecation annotation is useless, reject it. (Stability attribute is still required.)
|
|
DeprecationProhibited,
|
|
// Annotation itself is useless, but it can be propagated to children
|
|
Container,
|
|
}
|
|
|
|
/// Whether to inherit deprecation flags for nested items. In most cases, we do want to inherit
|
|
/// deprecation, because nested items rarely have individual deprecation attributes, and so
|
|
/// should be treated as deprecated if their parent is. However, default generic parameters
|
|
/// have separate deprecation attributes from their parents, so we do not wish to inherit
|
|
/// deprecation in this case. For example, inheriting deprecation for `T` in `Foo<T>`
|
|
/// would cause a duplicate warning arising from both `Foo` and `T` being deprecated.
|
|
#[derive(Clone)]
|
|
enum InheritDeprecation {
|
|
Yes,
|
|
No,
|
|
}
|
|
|
|
impl InheritDeprecation {
|
|
fn yes(&self) -> bool {
|
|
matches!(self, InheritDeprecation::Yes)
|
|
}
|
|
}
|
|
|
|
/// Whether to inherit const stability flags for nested items. In most cases, we do not want to
|
|
/// inherit const stability: just because an enclosing `fn` is const-stable does not mean
|
|
/// all `extern` imports declared in it should be const-stable! However, trait methods
|
|
/// inherit const stability attributes from their parent and do not have their own.
|
|
enum InheritConstStability {
|
|
Yes,
|
|
No,
|
|
}
|
|
|
|
impl InheritConstStability {
|
|
fn yes(&self) -> bool {
|
|
matches!(self, InheritConstStability::Yes)
|
|
}
|
|
}
|
|
|
|
enum InheritStability {
|
|
Yes,
|
|
No,
|
|
}
|
|
|
|
impl InheritStability {
|
|
fn yes(&self) -> bool {
|
|
matches!(self, InheritStability::Yes)
|
|
}
|
|
}
|
|
|
|
// A private tree-walker for producing an Index.
|
|
struct Annotator<'a, 'tcx> {
|
|
tcx: TyCtxt<'tcx>,
|
|
index: &'a mut Index,
|
|
parent_stab: Option<Stability>,
|
|
parent_const_stab: Option<ConstStability>,
|
|
parent_depr: Option<DeprecationEntry>,
|
|
in_trait_impl: bool,
|
|
}
|
|
|
|
impl<'a, 'tcx> Annotator<'a, 'tcx> {
|
|
// Determine the stability for a node based on its attributes and inherited
|
|
// stability. The stability is recorded in the index and used as the parent.
|
|
// If the node is a function, `fn_sig` is its signature
|
|
fn annotate<F>(
|
|
&mut self,
|
|
def_id: LocalDefId,
|
|
item_sp: Span,
|
|
fn_sig: Option<&'tcx hir::FnSig<'tcx>>,
|
|
kind: AnnotationKind,
|
|
inherit_deprecation: InheritDeprecation,
|
|
inherit_const_stability: InheritConstStability,
|
|
inherit_from_parent: InheritStability,
|
|
visit_children: F,
|
|
) where
|
|
F: FnOnce(&mut Self),
|
|
{
|
|
let attrs = self.tcx.get_attrs(def_id.to_def_id());
|
|
debug!("annotate(id = {:?}, attrs = {:?})", def_id, attrs);
|
|
|
|
let depr = attr::find_deprecation(&self.tcx.sess, attrs);
|
|
let mut is_deprecated = false;
|
|
if let Some((depr, span)) = &depr {
|
|
is_deprecated = true;
|
|
|
|
if kind == AnnotationKind::Prohibited || kind == AnnotationKind::DeprecationProhibited {
|
|
let hir_id = self.tcx.hir().local_def_id_to_hir_id(def_id);
|
|
self.tcx.struct_span_lint_hir(USELESS_DEPRECATED, hir_id, *span, |lint| {
|
|
lint.build("this `#[deprecated]` annotation has no effect")
|
|
.span_suggestion_short(
|
|
*span,
|
|
"remove the unnecessary deprecation attribute",
|
|
String::new(),
|
|
rustc_errors::Applicability::MachineApplicable,
|
|
)
|
|
.emit();
|
|
});
|
|
}
|
|
|
|
// `Deprecation` is just two pointers, no need to intern it
|
|
let depr_entry = DeprecationEntry::local(*depr, def_id);
|
|
self.index.depr_map.insert(def_id, depr_entry);
|
|
} else if let Some(parent_depr) = self.parent_depr {
|
|
if inherit_deprecation.yes() {
|
|
is_deprecated = true;
|
|
info!("tagging child {:?} as deprecated from parent", def_id);
|
|
self.index.depr_map.insert(def_id, parent_depr);
|
|
}
|
|
}
|
|
|
|
if !self.tcx.features().staged_api {
|
|
// Propagate unstability. This can happen even for non-staged-api crates in case
|
|
// -Zforce-unstable-if-unmarked is set.
|
|
if let Some(stab) = self.parent_stab {
|
|
if inherit_deprecation.yes() && stab.level.is_unstable() {
|
|
self.index.stab_map.insert(def_id, stab);
|
|
}
|
|
}
|
|
|
|
self.recurse_with_stability_attrs(
|
|
depr.map(|(d, _)| DeprecationEntry::local(d, def_id)),
|
|
None,
|
|
None,
|
|
visit_children,
|
|
);
|
|
return;
|
|
}
|
|
|
|
let (stab, const_stab) = attr::find_stability(&self.tcx.sess, attrs, item_sp);
|
|
let mut const_span = None;
|
|
|
|
let const_stab = const_stab.map(|(const_stab, const_span_node)| {
|
|
self.index.const_stab_map.insert(def_id, const_stab);
|
|
const_span = Some(const_span_node);
|
|
const_stab
|
|
});
|
|
|
|
// If the current node is a function, has const stability attributes and if it doesn not have an intrinsic ABI,
|
|
// check if the function/method is const or the parent impl block is const
|
|
if let (Some(const_span), Some(fn_sig)) = (const_span, fn_sig) {
|
|
if fn_sig.header.abi != Abi::RustIntrinsic
|
|
&& fn_sig.header.abi != Abi::PlatformIntrinsic
|
|
&& !fn_sig.header.is_const()
|
|
{
|
|
if !self.in_trait_impl
|
|
|| (self.in_trait_impl && !self.tcx.is_const_fn_raw(def_id.to_def_id()))
|
|
{
|
|
missing_const_err(&self.tcx.sess, fn_sig.span, const_span);
|
|
}
|
|
}
|
|
}
|
|
|
|
// `impl const Trait for Type` items forward their const stability to their
|
|
// immediate children.
|
|
if const_stab.is_none() {
|
|
debug!("annotate: const_stab not found, parent = {:?}", self.parent_const_stab);
|
|
if let Some(parent) = self.parent_const_stab {
|
|
if parent.level.is_unstable() {
|
|
self.index.const_stab_map.insert(def_id, parent);
|
|
}
|
|
}
|
|
}
|
|
|
|
if let Some((rustc_attr::Deprecation { is_since_rustc_version: true, .. }, span)) = &depr {
|
|
if stab.is_none() {
|
|
struct_span_err!(
|
|
self.tcx.sess,
|
|
*span,
|
|
E0549,
|
|
"deprecated attribute must be paired with \
|
|
either stable or unstable attribute"
|
|
)
|
|
.emit();
|
|
}
|
|
}
|
|
|
|
let stab = stab.map(|(stab, span)| {
|
|
// Error if prohibited, or can't inherit anything from a container.
|
|
if kind == AnnotationKind::Prohibited
|
|
|| (kind == AnnotationKind::Container && stab.level.is_stable() && is_deprecated)
|
|
{
|
|
self.tcx.sess.struct_span_err(span,"this stability annotation is useless")
|
|
.span_label(span, "useless stability annotation")
|
|
.span_label(item_sp, "the stability attribute annotates this item")
|
|
.emit();
|
|
}
|
|
|
|
debug!("annotate: found {:?}", stab);
|
|
|
|
// Check if deprecated_since < stable_since. If it is,
|
|
// this is *almost surely* an accident.
|
|
if let (&Some(dep_since), &attr::Stable { since: stab_since }) =
|
|
(&depr.as_ref().and_then(|(d, _)| d.since), &stab.level)
|
|
{
|
|
// Explicit version of iter::order::lt to handle parse errors properly
|
|
for (dep_v, stab_v) in
|
|
iter::zip(dep_since.as_str().split('.'), stab_since.as_str().split('.'))
|
|
{
|
|
match stab_v.parse::<u64>() {
|
|
Err(_) => {
|
|
self.tcx.sess.struct_span_err(span, "invalid stability version found")
|
|
.span_label(span, "invalid stability version")
|
|
.span_label(item_sp, "the stability attribute annotates this item")
|
|
.emit();
|
|
break;
|
|
}
|
|
Ok(stab_vp) => match dep_v.parse::<u64>() {
|
|
Ok(dep_vp) => match dep_vp.cmp(&stab_vp) {
|
|
Ordering::Less => {
|
|
self.tcx.sess.struct_span_err(span, "an API can't be stabilized after it is deprecated")
|
|
.span_label(span, "invalid version")
|
|
.span_label(item_sp, "the stability attribute annotates this item")
|
|
.emit();
|
|
break;
|
|
}
|
|
Ordering::Equal => continue,
|
|
Ordering::Greater => break,
|
|
},
|
|
Err(_) => {
|
|
if dep_v != "TBD" {
|
|
self.tcx.sess.struct_span_err(span, "invalid deprecation version found")
|
|
.span_label(span, "invalid deprecation version")
|
|
.span_label(item_sp, "the stability attribute annotates this item")
|
|
.emit();
|
|
}
|
|
break;
|
|
}
|
|
},
|
|
}
|
|
}
|
|
}
|
|
|
|
self.index.stab_map.insert(def_id, stab);
|
|
stab
|
|
});
|
|
|
|
if stab.is_none() {
|
|
debug!("annotate: stab not found, parent = {:?}", self.parent_stab);
|
|
if let Some(stab) = self.parent_stab {
|
|
if inherit_deprecation.yes() && stab.level.is_unstable()
|
|
|| inherit_from_parent.yes()
|
|
{
|
|
self.index.stab_map.insert(def_id, stab);
|
|
}
|
|
}
|
|
}
|
|
|
|
self.recurse_with_stability_attrs(
|
|
depr.map(|(d, _)| DeprecationEntry::local(d, def_id)),
|
|
stab,
|
|
if inherit_const_stability.yes() { const_stab } else { None },
|
|
visit_children,
|
|
);
|
|
}
|
|
|
|
fn recurse_with_stability_attrs(
|
|
&mut self,
|
|
depr: Option<DeprecationEntry>,
|
|
stab: Option<Stability>,
|
|
const_stab: Option<ConstStability>,
|
|
f: impl FnOnce(&mut Self),
|
|
) {
|
|
// These will be `Some` if this item changes the corresponding stability attribute.
|
|
let mut replaced_parent_depr = None;
|
|
let mut replaced_parent_stab = None;
|
|
let mut replaced_parent_const_stab = None;
|
|
|
|
if let Some(depr) = depr {
|
|
replaced_parent_depr = Some(replace(&mut self.parent_depr, Some(depr)));
|
|
}
|
|
if let Some(stab) = stab {
|
|
replaced_parent_stab = Some(replace(&mut self.parent_stab, Some(stab)));
|
|
}
|
|
if let Some(const_stab) = const_stab {
|
|
replaced_parent_const_stab =
|
|
Some(replace(&mut self.parent_const_stab, Some(const_stab)));
|
|
}
|
|
|
|
f(self);
|
|
|
|
if let Some(orig_parent_depr) = replaced_parent_depr {
|
|
self.parent_depr = orig_parent_depr;
|
|
}
|
|
if let Some(orig_parent_stab) = replaced_parent_stab {
|
|
self.parent_stab = orig_parent_stab;
|
|
}
|
|
if let Some(orig_parent_const_stab) = replaced_parent_const_stab {
|
|
self.parent_const_stab = orig_parent_const_stab;
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> {
|
|
/// Because stability levels are scoped lexically, we want to walk
|
|
/// nested items in the context of the outer item, so enable
|
|
/// deep-walking.
|
|
type NestedFilter = nested_filter::All;
|
|
|
|
fn nested_visit_map(&mut self) -> Self::Map {
|
|
self.tcx.hir()
|
|
}
|
|
|
|
fn visit_item(&mut self, i: &'tcx Item<'tcx>) {
|
|
let orig_in_trait_impl = self.in_trait_impl;
|
|
let mut kind = AnnotationKind::Required;
|
|
let mut const_stab_inherit = InheritConstStability::No;
|
|
let mut fn_sig = None;
|
|
|
|
match i.kind {
|
|
// Inherent impls and foreign modules serve only as containers for other items,
|
|
// they don't have their own stability. They still can be annotated as unstable
|
|
// and propagate this instability to children, but this annotation is completely
|
|
// optional. They inherit stability from their parents when unannotated.
|
|
hir::ItemKind::Impl(hir::Impl { of_trait: None, .. })
|
|
| hir::ItemKind::ForeignMod { .. } => {
|
|
self.in_trait_impl = false;
|
|
kind = AnnotationKind::Container;
|
|
}
|
|
hir::ItemKind::Impl(hir::Impl { of_trait: Some(_), .. }) => {
|
|
self.in_trait_impl = true;
|
|
kind = AnnotationKind::DeprecationProhibited;
|
|
const_stab_inherit = InheritConstStability::Yes;
|
|
}
|
|
hir::ItemKind::Struct(ref sd, _) => {
|
|
if let Some(ctor_hir_id) = sd.ctor_hir_id() {
|
|
self.annotate(
|
|
self.tcx.hir().local_def_id(ctor_hir_id),
|
|
i.span,
|
|
None,
|
|
AnnotationKind::Required,
|
|
InheritDeprecation::Yes,
|
|
InheritConstStability::No,
|
|
InheritStability::Yes,
|
|
|_| {},
|
|
)
|
|
}
|
|
}
|
|
hir::ItemKind::Fn(ref item_fn_sig, _, _) => {
|
|
fn_sig = Some(item_fn_sig);
|
|
}
|
|
_ => {}
|
|
}
|
|
|
|
self.annotate(
|
|
i.def_id,
|
|
i.span,
|
|
fn_sig,
|
|
kind,
|
|
InheritDeprecation::Yes,
|
|
const_stab_inherit,
|
|
InheritStability::No,
|
|
|v| intravisit::walk_item(v, i),
|
|
);
|
|
self.in_trait_impl = orig_in_trait_impl;
|
|
}
|
|
|
|
fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem<'tcx>) {
|
|
let fn_sig = match ti.kind {
|
|
hir::TraitItemKind::Fn(ref fn_sig, _) => Some(fn_sig),
|
|
_ => None,
|
|
};
|
|
|
|
self.annotate(
|
|
ti.def_id,
|
|
ti.span,
|
|
fn_sig,
|
|
AnnotationKind::Required,
|
|
InheritDeprecation::Yes,
|
|
InheritConstStability::No,
|
|
InheritStability::No,
|
|
|v| {
|
|
intravisit::walk_trait_item(v, ti);
|
|
},
|
|
);
|
|
}
|
|
|
|
fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem<'tcx>) {
|
|
let kind =
|
|
if self.in_trait_impl { AnnotationKind::Prohibited } else { AnnotationKind::Required };
|
|
|
|
let fn_sig = match ii.kind {
|
|
hir::ImplItemKind::Fn(ref fn_sig, _) => Some(fn_sig),
|
|
_ => None,
|
|
};
|
|
|
|
self.annotate(
|
|
ii.def_id,
|
|
ii.span,
|
|
fn_sig,
|
|
kind,
|
|
InheritDeprecation::Yes,
|
|
InheritConstStability::No,
|
|
InheritStability::No,
|
|
|v| {
|
|
intravisit::walk_impl_item(v, ii);
|
|
},
|
|
);
|
|
}
|
|
|
|
fn visit_variant(&mut self, var: &'tcx Variant<'tcx>, g: &'tcx Generics<'tcx>, item_id: HirId) {
|
|
self.annotate(
|
|
self.tcx.hir().local_def_id(var.id),
|
|
var.span,
|
|
None,
|
|
AnnotationKind::Required,
|
|
InheritDeprecation::Yes,
|
|
InheritConstStability::No,
|
|
InheritStability::Yes,
|
|
|v| {
|
|
if let Some(ctor_hir_id) = var.data.ctor_hir_id() {
|
|
v.annotate(
|
|
v.tcx.hir().local_def_id(ctor_hir_id),
|
|
var.span,
|
|
None,
|
|
AnnotationKind::Required,
|
|
InheritDeprecation::Yes,
|
|
InheritConstStability::No,
|
|
InheritStability::No,
|
|
|_| {},
|
|
);
|
|
}
|
|
|
|
intravisit::walk_variant(v, var, g, item_id)
|
|
},
|
|
)
|
|
}
|
|
|
|
fn visit_field_def(&mut self, s: &'tcx FieldDef<'tcx>) {
|
|
self.annotate(
|
|
self.tcx.hir().local_def_id(s.hir_id),
|
|
s.span,
|
|
None,
|
|
AnnotationKind::Required,
|
|
InheritDeprecation::Yes,
|
|
InheritConstStability::No,
|
|
InheritStability::Yes,
|
|
|v| {
|
|
intravisit::walk_field_def(v, s);
|
|
},
|
|
);
|
|
}
|
|
|
|
fn visit_foreign_item(&mut self, i: &'tcx hir::ForeignItem<'tcx>) {
|
|
self.annotate(
|
|
i.def_id,
|
|
i.span,
|
|
None,
|
|
AnnotationKind::Required,
|
|
InheritDeprecation::Yes,
|
|
InheritConstStability::No,
|
|
InheritStability::No,
|
|
|v| {
|
|
intravisit::walk_foreign_item(v, i);
|
|
},
|
|
);
|
|
}
|
|
|
|
fn visit_generic_param(&mut self, p: &'tcx hir::GenericParam<'tcx>) {
|
|
let kind = match &p.kind {
|
|
// Allow stability attributes on default generic arguments.
|
|
hir::GenericParamKind::Type { default: Some(_), .. }
|
|
| hir::GenericParamKind::Const { default: Some(_), .. } => AnnotationKind::Container,
|
|
_ => AnnotationKind::Prohibited,
|
|
};
|
|
|
|
self.annotate(
|
|
self.tcx.hir().local_def_id(p.hir_id),
|
|
p.span,
|
|
None,
|
|
kind,
|
|
InheritDeprecation::No,
|
|
InheritConstStability::No,
|
|
InheritStability::No,
|
|
|v| {
|
|
intravisit::walk_generic_param(v, p);
|
|
},
|
|
);
|
|
}
|
|
}
|
|
|
|
struct MissingStabilityAnnotations<'tcx> {
|
|
tcx: TyCtxt<'tcx>,
|
|
access_levels: &'tcx AccessLevels,
|
|
}
|
|
|
|
impl<'tcx> MissingStabilityAnnotations<'tcx> {
|
|
fn check_missing_stability(&self, def_id: LocalDefId, span: Span) {
|
|
let stab = self.tcx.stability().local_stability(def_id);
|
|
if !self.tcx.sess.opts.test && stab.is_none() && self.access_levels.is_reachable(def_id) {
|
|
let descr = self.tcx.def_kind(def_id).descr(def_id.to_def_id());
|
|
self.tcx.sess.span_err(span, &format!("{} has missing stability attribute", descr));
|
|
}
|
|
}
|
|
|
|
fn check_missing_const_stability(&self, def_id: LocalDefId, span: Span) {
|
|
if !self.tcx.features().staged_api {
|
|
return;
|
|
}
|
|
|
|
let is_const = self.tcx.is_const_fn(def_id.to_def_id());
|
|
let is_stable = self
|
|
.tcx
|
|
.lookup_stability(def_id)
|
|
.map_or(false, |stability| stability.level.is_stable());
|
|
let missing_const_stability_attribute = self.tcx.lookup_const_stability(def_id).is_none();
|
|
let is_reachable = self.access_levels.is_reachable(def_id);
|
|
|
|
if is_const && is_stable && missing_const_stability_attribute && is_reachable {
|
|
let descr = self.tcx.def_kind(def_id).descr(def_id.to_def_id());
|
|
self.tcx.sess.span_err(span, &format!("{descr} has missing const stability attribute"));
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'tcx> Visitor<'tcx> for MissingStabilityAnnotations<'tcx> {
|
|
type NestedFilter = nested_filter::OnlyBodies;
|
|
|
|
fn nested_visit_map(&mut self) -> Self::Map {
|
|
self.tcx.hir()
|
|
}
|
|
|
|
fn visit_item(&mut self, i: &'tcx Item<'tcx>) {
|
|
// Inherent impls and foreign modules serve only as containers for other items,
|
|
// they don't have their own stability. They still can be annotated as unstable
|
|
// and propagate this instability to children, but this annotation is completely
|
|
// optional. They inherit stability from their parents when unannotated.
|
|
if !matches!(
|
|
i.kind,
|
|
hir::ItemKind::Impl(hir::Impl { of_trait: None, .. })
|
|
| hir::ItemKind::ForeignMod { .. }
|
|
) {
|
|
self.check_missing_stability(i.def_id, i.span);
|
|
}
|
|
|
|
// Ensure stable `const fn` have a const stability attribute.
|
|
self.check_missing_const_stability(i.def_id, i.span);
|
|
|
|
intravisit::walk_item(self, i)
|
|
}
|
|
|
|
fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem<'tcx>) {
|
|
self.check_missing_stability(ti.def_id, ti.span);
|
|
intravisit::walk_trait_item(self, ti);
|
|
}
|
|
|
|
fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem<'tcx>) {
|
|
let impl_def_id = self.tcx.hir().get_parent_item(ii.hir_id());
|
|
if self.tcx.impl_trait_ref(impl_def_id).is_none() {
|
|
self.check_missing_stability(ii.def_id, ii.span);
|
|
self.check_missing_const_stability(ii.def_id, ii.span);
|
|
}
|
|
intravisit::walk_impl_item(self, ii);
|
|
}
|
|
|
|
fn visit_variant(&mut self, var: &'tcx Variant<'tcx>, g: &'tcx Generics<'tcx>, item_id: HirId) {
|
|
self.check_missing_stability(self.tcx.hir().local_def_id(var.id), var.span);
|
|
intravisit::walk_variant(self, var, g, item_id);
|
|
}
|
|
|
|
fn visit_field_def(&mut self, s: &'tcx FieldDef<'tcx>) {
|
|
self.check_missing_stability(self.tcx.hir().local_def_id(s.hir_id), s.span);
|
|
intravisit::walk_field_def(self, s);
|
|
}
|
|
|
|
fn visit_foreign_item(&mut self, i: &'tcx hir::ForeignItem<'tcx>) {
|
|
self.check_missing_stability(i.def_id, i.span);
|
|
intravisit::walk_foreign_item(self, i);
|
|
}
|
|
// Note that we don't need to `check_missing_stability` for default generic parameters,
|
|
// as we assume that any default generic parameters without attributes are automatically
|
|
// stable (assuming they have not inherited instability from their parent).
|
|
}
|
|
|
|
fn stability_index(tcx: TyCtxt<'_>, (): ()) -> Index {
|
|
let mut index = Index {
|
|
stab_map: Default::default(),
|
|
const_stab_map: Default::default(),
|
|
depr_map: Default::default(),
|
|
};
|
|
|
|
{
|
|
let mut annotator = Annotator {
|
|
tcx,
|
|
index: &mut index,
|
|
parent_stab: None,
|
|
parent_const_stab: None,
|
|
parent_depr: None,
|
|
in_trait_impl: false,
|
|
};
|
|
|
|
// If the `-Z force-unstable-if-unmarked` flag is passed then we provide
|
|
// a parent stability annotation which indicates that this is private
|
|
// with the `rustc_private` feature. This is intended for use when
|
|
// compiling `librustc_*` crates themselves so we can leverage crates.io
|
|
// while maintaining the invariant that all sysroot crates are unstable
|
|
// by default and are unable to be used.
|
|
if tcx.sess.opts.debugging_opts.force_unstable_if_unmarked {
|
|
let reason = "this crate is being loaded from the sysroot, an \
|
|
unstable location; did you mean to load this crate \
|
|
from crates.io via `Cargo.toml` instead?";
|
|
let stability = Stability {
|
|
level: attr::StabilityLevel::Unstable {
|
|
reason: Some(Symbol::intern(reason)),
|
|
issue: NonZeroU32::new(27812),
|
|
is_soft: false,
|
|
},
|
|
feature: sym::rustc_private,
|
|
};
|
|
annotator.parent_stab = Some(stability);
|
|
}
|
|
|
|
annotator.annotate(
|
|
CRATE_DEF_ID,
|
|
tcx.hir().span(CRATE_HIR_ID),
|
|
None,
|
|
AnnotationKind::Required,
|
|
InheritDeprecation::Yes,
|
|
InheritConstStability::No,
|
|
InheritStability::No,
|
|
|v| tcx.hir().walk_toplevel_module(v),
|
|
);
|
|
}
|
|
index
|
|
}
|
|
|
|
/// Cross-references the feature names of unstable APIs with enabled
|
|
/// features and possibly prints errors.
|
|
fn check_mod_unstable_api_usage(tcx: TyCtxt<'_>, module_def_id: LocalDefId) {
|
|
tcx.hir().visit_item_likes_in_module(module_def_id, &mut Checker { tcx }.as_deep_visitor());
|
|
}
|
|
|
|
pub(crate) fn provide(providers: &mut Providers) {
|
|
*providers = Providers {
|
|
check_mod_unstable_api_usage,
|
|
stability_index,
|
|
lookup_stability: |tcx, id| tcx.stability().local_stability(id.expect_local()),
|
|
lookup_const_stability: |tcx, id| tcx.stability().local_const_stability(id.expect_local()),
|
|
lookup_deprecation_entry: |tcx, id| {
|
|
tcx.stability().local_deprecation_entry(id.expect_local())
|
|
},
|
|
..*providers
|
|
};
|
|
}
|
|
|
|
struct Checker<'tcx> {
|
|
tcx: TyCtxt<'tcx>,
|
|
}
|
|
|
|
impl<'tcx> Visitor<'tcx> for Checker<'tcx> {
|
|
type NestedFilter = nested_filter::OnlyBodies;
|
|
|
|
/// Because stability levels are scoped lexically, we want to walk
|
|
/// nested items in the context of the outer item, so enable
|
|
/// deep-walking.
|
|
fn nested_visit_map(&mut self) -> Self::Map {
|
|
self.tcx.hir()
|
|
}
|
|
|
|
fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
|
|
match item.kind {
|
|
hir::ItemKind::ExternCrate(_) => {
|
|
// compiler-generated `extern crate` items have a dummy span.
|
|
// `std` is still checked for the `restricted-std` feature.
|
|
if item.span.is_dummy() && item.ident.name != sym::std {
|
|
return;
|
|
}
|
|
|
|
let Some(cnum) = self.tcx.extern_mod_stmt_cnum(item.def_id) else {
|
|
return;
|
|
};
|
|
let def_id = cnum.as_def_id();
|
|
self.tcx.check_stability(def_id, Some(item.hir_id()), item.span, None);
|
|
}
|
|
|
|
// For implementations of traits, check the stability of each item
|
|
// individually as it's possible to have a stable trait with unstable
|
|
// items.
|
|
hir::ItemKind::Impl(hir::Impl { of_trait: Some(ref t), self_ty, items, .. }) => {
|
|
if self.tcx.features().staged_api {
|
|
// If this impl block has an #[unstable] attribute, give an
|
|
// error if all involved types and traits are stable, because
|
|
// it will have no effect.
|
|
// See: https://github.com/rust-lang/rust/issues/55436
|
|
let attrs = self.tcx.hir().attrs(item.hir_id());
|
|
if let (Some((Stability { level: attr::Unstable { .. }, .. }, span)), _) =
|
|
attr::find_stability(&self.tcx.sess, attrs, item.span)
|
|
{
|
|
let mut c = CheckTraitImplStable { tcx: self.tcx, fully_stable: true };
|
|
c.visit_ty(self_ty);
|
|
c.visit_trait_ref(t);
|
|
if c.fully_stable {
|
|
self.tcx.struct_span_lint_hir(
|
|
INEFFECTIVE_UNSTABLE_TRAIT_IMPL,
|
|
item.hir_id(),
|
|
span,
|
|
|lint| {lint
|
|
.build("an `#[unstable]` annotation here has no effect")
|
|
.note("see issue #55436 <https://github.com/rust-lang/rust/issues/55436> for more information")
|
|
.emit();}
|
|
);
|
|
}
|
|
}
|
|
}
|
|
|
|
for impl_item_ref in *items {
|
|
let impl_item = self.tcx.associated_item(impl_item_ref.id.def_id);
|
|
|
|
if let Some(def_id) = impl_item.trait_item_def_id {
|
|
// Pass `None` to skip deprecation warnings.
|
|
self.tcx.check_stability(def_id, None, impl_item_ref.span, None);
|
|
}
|
|
}
|
|
}
|
|
|
|
// There's no good place to insert stability check for non-Copy unions,
|
|
// so semi-randomly perform it here in stability.rs
|
|
hir::ItemKind::Union(..) if !self.tcx.features().untagged_unions => {
|
|
let ty = self.tcx.type_of(item.def_id);
|
|
let ty::Adt(adt_def, substs) = ty.kind() else { bug!() };
|
|
|
|
// Non-`Copy` fields are unstable, except for `ManuallyDrop`.
|
|
let param_env = self.tcx.param_env(item.def_id);
|
|
for field in &adt_def.non_enum_variant().fields {
|
|
let field_ty = field.ty(self.tcx, substs);
|
|
if !field_ty.ty_adt_def().map_or(false, |adt_def| adt_def.is_manually_drop())
|
|
&& !field_ty.is_copy_modulo_regions(self.tcx.at(DUMMY_SP), param_env)
|
|
{
|
|
if field_ty.needs_drop(self.tcx, param_env) {
|
|
// Avoid duplicate error: This will error later anyway because fields
|
|
// that need drop are not allowed.
|
|
self.tcx.sess.delay_span_bug(
|
|
item.span,
|
|
"union should have been rejected due to potentially dropping field",
|
|
);
|
|
} else {
|
|
feature_err(
|
|
&self.tcx.sess.parse_sess,
|
|
sym::untagged_unions,
|
|
self.tcx.def_span(field.did),
|
|
"unions with non-`Copy` fields other than `ManuallyDrop<T>` are unstable",
|
|
)
|
|
.emit();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
_ => (/* pass */),
|
|
}
|
|
intravisit::walk_item(self, item);
|
|
}
|
|
|
|
fn visit_path(&mut self, path: &'tcx hir::Path<'tcx>, id: hir::HirId) {
|
|
if let Some(def_id) = path.res.opt_def_id() {
|
|
let method_span = path.segments.last().map(|s| s.ident.span);
|
|
self.tcx.check_stability(def_id, Some(id), path.span, method_span)
|
|
}
|
|
intravisit::walk_path(self, path)
|
|
}
|
|
}
|
|
|
|
struct CheckTraitImplStable<'tcx> {
|
|
tcx: TyCtxt<'tcx>,
|
|
fully_stable: bool,
|
|
}
|
|
|
|
impl<'tcx> Visitor<'tcx> for CheckTraitImplStable<'tcx> {
|
|
fn visit_path(&mut self, path: &'tcx hir::Path<'tcx>, _id: hir::HirId) {
|
|
if let Some(def_id) = path.res.opt_def_id() {
|
|
if let Some(stab) = self.tcx.lookup_stability(def_id) {
|
|
self.fully_stable &= stab.level.is_stable();
|
|
}
|
|
}
|
|
intravisit::walk_path(self, path)
|
|
}
|
|
|
|
fn visit_trait_ref(&mut self, t: &'tcx TraitRef<'tcx>) {
|
|
if let Res::Def(DefKind::Trait, trait_did) = t.path.res {
|
|
if let Some(stab) = self.tcx.lookup_stability(trait_did) {
|
|
self.fully_stable &= stab.level.is_stable();
|
|
}
|
|
}
|
|
intravisit::walk_trait_ref(self, t)
|
|
}
|
|
|
|
fn visit_ty(&mut self, t: &'tcx Ty<'tcx>) {
|
|
if let TyKind::Never = t.kind {
|
|
self.fully_stable = false;
|
|
}
|
|
intravisit::walk_ty(self, t)
|
|
}
|
|
}
|
|
|
|
/// Given the list of enabled features that were not language features (i.e., that
|
|
/// were expected to be library features), and the list of features used from
|
|
/// libraries, identify activated features that don't exist and error about them.
|
|
pub fn check_unused_or_stable_features(tcx: TyCtxt<'_>) {
|
|
let is_staged_api =
|
|
tcx.sess.opts.debugging_opts.force_unstable_if_unmarked || tcx.features().staged_api;
|
|
if is_staged_api {
|
|
let access_levels = &tcx.privacy_access_levels(());
|
|
let mut missing = MissingStabilityAnnotations { tcx, access_levels };
|
|
missing.check_missing_stability(CRATE_DEF_ID, tcx.hir().span(CRATE_HIR_ID));
|
|
tcx.hir().walk_toplevel_module(&mut missing);
|
|
tcx.hir().visit_all_item_likes(&mut missing.as_deep_visitor());
|
|
}
|
|
|
|
let declared_lang_features = &tcx.features().declared_lang_features;
|
|
let mut lang_features = FxHashSet::default();
|
|
for &(feature, span, since) in declared_lang_features {
|
|
if let Some(since) = since {
|
|
// Warn if the user has enabled an already-stable lang feature.
|
|
unnecessary_stable_feature_lint(tcx, span, feature, since);
|
|
}
|
|
if !lang_features.insert(feature) {
|
|
// Warn if the user enables a lang feature multiple times.
|
|
duplicate_feature_err(tcx.sess, span, feature);
|
|
}
|
|
}
|
|
|
|
let declared_lib_features = &tcx.features().declared_lib_features;
|
|
let mut remaining_lib_features = FxIndexMap::default();
|
|
for (feature, span) in declared_lib_features {
|
|
if !tcx.sess.opts.unstable_features.is_nightly_build() {
|
|
struct_span_err!(
|
|
tcx.sess,
|
|
*span,
|
|
E0554,
|
|
"`#![feature]` may not be used on the {} release channel",
|
|
env!("CFG_RELEASE_CHANNEL")
|
|
)
|
|
.emit();
|
|
}
|
|
if remaining_lib_features.contains_key(&feature) {
|
|
// Warn if the user enables a lib feature multiple times.
|
|
duplicate_feature_err(tcx.sess, *span, *feature);
|
|
}
|
|
remaining_lib_features.insert(feature, *span);
|
|
}
|
|
// `stdbuild` has special handling for `libc`, so we need to
|
|
// recognise the feature when building std.
|
|
// Likewise, libtest is handled specially, so `test` isn't
|
|
// available as we'd like it to be.
|
|
// FIXME: only remove `libc` when `stdbuild` is active.
|
|
// FIXME: remove special casing for `test`.
|
|
remaining_lib_features.remove(&sym::libc);
|
|
remaining_lib_features.remove(&sym::test);
|
|
|
|
let check_features = |remaining_lib_features: &mut FxIndexMap<_, _>, defined_features: &[_]| {
|
|
for &(feature, since) in defined_features {
|
|
if let Some(since) = since {
|
|
if let Some(span) = remaining_lib_features.get(&feature) {
|
|
// Warn if the user has enabled an already-stable lib feature.
|
|
unnecessary_stable_feature_lint(tcx, *span, feature, since);
|
|
}
|
|
}
|
|
remaining_lib_features.remove(&feature);
|
|
if remaining_lib_features.is_empty() {
|
|
break;
|
|
}
|
|
}
|
|
};
|
|
|
|
// We always collect the lib features declared in the current crate, even if there are
|
|
// no unknown features, because the collection also does feature attribute validation.
|
|
let local_defined_features = tcx.lib_features(()).to_vec();
|
|
if !remaining_lib_features.is_empty() {
|
|
check_features(&mut remaining_lib_features, &local_defined_features);
|
|
|
|
for &cnum in tcx.crates(()) {
|
|
if remaining_lib_features.is_empty() {
|
|
break;
|
|
}
|
|
check_features(&mut remaining_lib_features, tcx.defined_lib_features(cnum));
|
|
}
|
|
}
|
|
|
|
for (feature, span) in remaining_lib_features {
|
|
struct_span_err!(tcx.sess, span, E0635, "unknown feature `{}`", feature).emit();
|
|
}
|
|
|
|
// FIXME(#44232): the `used_features` table no longer exists, so we
|
|
// don't lint about unused features. We should re-enable this one day!
|
|
}
|
|
|
|
fn unnecessary_stable_feature_lint(tcx: TyCtxt<'_>, span: Span, feature: Symbol, since: Symbol) {
|
|
tcx.struct_span_lint_hir(lint::builtin::STABLE_FEATURES, hir::CRATE_HIR_ID, span, |lint| {
|
|
lint.build(&format!(
|
|
"the feature `{}` has been stable since {} and no longer requires \
|
|
an attribute to enable",
|
|
feature, since
|
|
))
|
|
.emit();
|
|
});
|
|
}
|
|
|
|
fn duplicate_feature_err(sess: &Session, span: Span, feature: Symbol) {
|
|
struct_span_err!(sess, span, E0636, "the feature `{}` has already been declared", feature)
|
|
.emit();
|
|
}
|
|
|
|
fn missing_const_err(session: &Session, fn_sig_span: Span, const_span: Span) {
|
|
const ERROR_MSG: &'static str = "attributes `#[rustc_const_unstable]` \
|
|
and `#[rustc_const_stable]` require \
|
|
the function or method to be `const`";
|
|
|
|
session
|
|
.struct_span_err(fn_sig_span, ERROR_MSG)
|
|
.span_help(fn_sig_span, "make the function or method const")
|
|
.span_label(const_span, "attribute specified here")
|
|
.emit();
|
|
}
|