Update tooling

This commit is contained in:
Maybe Waffle 2022-10-27 18:32:17 +04:00
parent 5b336fddd3
commit 471d855a8e
12 changed files with 134 additions and 91 deletions

View file

@ -26,7 +26,7 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, msrv: Option<RustcVer
(Mutability::Not, Mutability::Not) | (Mutability::Mut, Mutability::Mut));
// The `U` in `pointer::cast` have to be `Sized`
// as explained here: https://github.com/rust-lang/rust/issues/60602.
if to_pointee_ty.is_sized(cx.tcx.at(expr.span), cx.param_env);
if to_pointee_ty.is_sized(cx.tcx, cx.param_env);
then {
let mut applicability = Applicability::MachineApplicable;
let cast_expr_sugg = Sugg::hir_with_applicability(cx, cast_expr, "_", &mut applicability);

View file

@ -29,7 +29,7 @@ use rustc_middle::ty::{
};
use rustc_semver::RustcVersion;
use rustc_session::{declare_tool_lint, impl_lint_pass};
use rustc_span::{symbol::sym, Span, Symbol, DUMMY_SP};
use rustc_span::{symbol::sym, Span, Symbol};
use rustc_trait_selection::infer::InferCtxtExt as _;
use rustc_trait_selection::traits::{query::evaluate_obligation::InferCtxtExt as _, Obligation, ObligationCause};
use std::collections::VecDeque;
@ -990,7 +990,7 @@ fn binding_ty_auto_deref_stability<'tcx>(
cx.typeck_results().node_type(ty.ty.hir_id),
binder_args,
))
.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env.without_caller_bounds()),
.is_sized(cx.tcx, cx.param_env.without_caller_bounds()),
)
}
},
@ -1005,7 +1005,7 @@ fn binding_ty_auto_deref_stability<'tcx>(
cx.typeck_results().node_type(ty.ty.hir_id),
binder_args,
))
.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env.without_caller_bounds()),
.is_sized(cx.tcx, cx.param_env.without_caller_bounds()),
),
TyKind::OpaqueDef(..) | TyKind::Infer | TyKind::Typeof(..) | TyKind::TraitObject(..) | TyKind::Err => {
Position::ReborrowStable(precedence)
@ -1297,7 +1297,7 @@ impl<'tcx> TyPosition<'tcx> {
fn position_for_result(self, cx: &LateContext<'tcx>) -> Position {
match (self.position, self.ty) {
(Position::ReborrowStable(precedence), Some(ty)) => {
Position::DerefStable(precedence, ty.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env))
Position::DerefStable(precedence, ty.is_sized(cx.tcx, cx.param_env))
},
(position, _) => position,
}
@ -1348,7 +1348,7 @@ fn ty_auto_deref_stability<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, precedenc
| ty::Tuple(_)
| ty::Projection(_) => Position::DerefStable(
precedence,
ty.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env.without_caller_bounds()),
ty.is_sized(cx.tcx, cx.param_env.without_caller_bounds()),
)
.into(),
};

View file

@ -188,7 +188,7 @@ fn is_mutable_ty<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, span: Span, tys: &m
// primitive types are never mutable
ty::Bool | ty::Char | ty::Int(_) | ty::Uint(_) | ty::Float(_) | ty::Str => false,
ty::Adt(adt, substs) => {
tys.insert(adt.did()) && !ty.is_freeze(cx.tcx.at(span), cx.param_env)
tys.insert(adt.did()) && !ty.is_freeze(cx.tcx, cx.param_env)
|| KNOWN_WRAPPER_TYS
.iter()
.any(|&sym| cx.tcx.is_diagnostic_item(sym, adt.did()))

View file

@ -74,7 +74,7 @@ impl<'tcx> LateLintPass<'tcx> for LetIfSeq {
let span = stmt.span.to(if_.span);
let has_interior_mutability = !cx.typeck_results().node_type(canonical_id).is_freeze(
cx.tcx.at(span),
cx.tcx,
cx.param_env,
);
if has_interior_mutability { return; }

View file

@ -136,12 +136,14 @@ fn check_ty<'tcx>(cx: &LateContext<'tcx>, span: Span, ty: Ty<'tcx>) {
/// [`Hash`] or [`Ord`].
fn is_interior_mutable_type<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, span: Span) -> bool {
match *ty.kind() {
Ref(_, inner_ty, mutbl) => mutbl == hir::Mutability::Mut || is_interior_mutable_type(cx, inner_ty, span),
Ref(_, inner_ty, mutbl) => {
mutbl == hir::Mutability::Mut || is_interior_mutable_type(cx, inner_ty, span)
}
Slice(inner_ty) => is_interior_mutable_type(cx, inner_ty, span),
Array(inner_ty, size) => {
size.try_eval_usize(cx.tcx, cx.param_env).map_or(true, |u| u != 0)
&& is_interior_mutable_type(cx, inner_ty, span)
},
}
Tuple(fields) => fields.iter().any(|ty| is_interior_mutable_type(cx, ty, span)),
Adt(def, substs) => {
// Special case for collections in `std` who's impl of `Hash` or `Ord` delegates to
@ -167,9 +169,9 @@ fn is_interior_mutable_type<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, span: Sp
} else {
!ty.has_escaping_bound_vars()
&& cx.tcx.layout_of(cx.param_env.and(ty)).is_ok()
&& !ty.is_freeze(cx.tcx.at(span), cx.param_env)
&& !ty.is_freeze(cx.tcx, cx.param_env)
}
},
}
_ => false,
}
}

View file

@ -19,7 +19,7 @@ use rustc_middle::mir::FakeReadCause;
use rustc_middle::ty::{self, TypeVisitable};
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::symbol::kw;
use rustc_span::{sym, Span, DUMMY_SP};
use rustc_span::{sym, Span};
use rustc_target::spec::abi::Abi;
use rustc_trait_selection::traits;
use rustc_trait_selection::traits::misc::can_type_implement_copy;
@ -184,7 +184,7 @@ impl<'tcx> LateLintPass<'tcx> for NeedlessPassByValue {
if !is_self(arg);
if !ty.is_mutable_ptr();
if !is_copy(cx, ty);
if ty.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env);
if ty.is_sized(cx.tcx, cx.param_env);
if !allowed_traits.iter().any(|&t| implements_trait(cx, ty, t, &[]));
if !implements_borrow_trait;
if !all_borrowable_trait;

View file

@ -20,7 +20,7 @@ use rustc_middle::mir::interpret::{ConstValue, ErrorHandled};
use rustc_middle::ty::adjustment::Adjust;
use rustc_middle::ty::{self, Ty};
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::{sym, InnerSpan, Span, DUMMY_SP};
use rustc_span::{sym, InnerSpan, Span};
// FIXME: this is a correctness problem but there's no suitable
// warn-by-default category.
@ -136,7 +136,7 @@ fn is_unfrozen<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool {
// since it works when a pointer indirection involves (`Cell<*const T>`).
// Making up a `ParamEnv` where every generic params and assoc types are `Freeze`is another option;
// but I'm not sure whether it's a decent way, if possible.
cx.tcx.layout_of(cx.param_env.and(ty)).is_ok() && !ty.is_freeze(cx.tcx.at(DUMMY_SP), cx.param_env)
cx.tcx.layout_of(cx.param_env.and(ty)).is_ok() && !ty.is_freeze(cx.tcx, cx.param_env)
}
fn is_value_unfrozen_raw<'tcx>(

View file

@ -94,7 +94,7 @@ fn check_is_none_or_err_and_early_return<'tcx>(cx: &LateContext<'tcx>, expr: &Ex
then {
let mut applicability = Applicability::MachineApplicable;
let receiver_str = snippet_with_applicability(cx, caller.span, "..", &mut applicability);
let by_ref = !caller_ty.is_copy_modulo_regions(cx.tcx.at(caller.span), cx.param_env) &&
let by_ref = !caller_ty.is_copy_modulo_regions(cx.tcx, cx.param_env) &&
!matches!(caller.kind, ExprKind::Call(..) | ExprKind::MethodCall(..));
let sugg = if let Some(else_inner) = r#else {
if eq_expr_value(cx, caller, peel_blocks(else_inner)) {

View file

@ -5,7 +5,6 @@ use rustc_hir::Expr;
use rustc_lint::LateContext;
use rustc_middle::ty::SubstsRef;
use rustc_middle::ty::{self, IntTy, Ty, TypeAndMut, UintTy};
use rustc_span::DUMMY_SP;
#[expect(clippy::too_many_lines)]
pub(super) fn check<'tcx>(
@ -28,24 +27,32 @@ pub(super) fn check<'tcx>(
// `Repr(C)` <-> unordered type.
// If the first field of the `Repr(C)` type matches then the transmute is ok
(ReducedTy::OrderedFields(_, Some(from_sub_ty)), ReducedTy::UnorderedFields(to_sub_ty))
| (ReducedTy::UnorderedFields(from_sub_ty), ReducedTy::OrderedFields(_, Some(to_sub_ty))) => {
(
ReducedTy::OrderedFields(_, Some(from_sub_ty)),
ReducedTy::UnorderedFields(to_sub_ty),
)
| (
ReducedTy::UnorderedFields(from_sub_ty),
ReducedTy::OrderedFields(_, Some(to_sub_ty)),
) => {
from_ty = from_sub_ty;
to_ty = to_sub_ty;
continue;
},
(ReducedTy::OrderedFields(_, Some(from_sub_ty)), ReducedTy::Other(to_sub_ty)) if reduced_tys.to_fat_ptr => {
}
(ReducedTy::OrderedFields(_, Some(from_sub_ty)), ReducedTy::Other(to_sub_ty))
if reduced_tys.to_fat_ptr =>
{
from_ty = from_sub_ty;
to_ty = to_sub_ty;
continue;
},
}
(ReducedTy::Other(from_sub_ty), ReducedTy::OrderedFields(_, Some(to_sub_ty)))
if reduced_tys.from_fat_ptr =>
{
from_ty = from_sub_ty;
to_ty = to_sub_ty;
continue;
},
}
// ptr <-> ptr
(ReducedTy::Other(from_sub_ty), ReducedTy::Other(to_sub_ty))
@ -55,19 +62,19 @@ pub(super) fn check<'tcx>(
from_ty = from_sub_ty;
to_ty = to_sub_ty;
continue;
},
}
// fat ptr <-> (*size, *size)
(ReducedTy::Other(_), ReducedTy::UnorderedFields(to_ty))
if reduced_tys.from_fat_ptr && is_size_pair(to_ty) =>
{
return false;
},
}
(ReducedTy::UnorderedFields(from_ty), ReducedTy::Other(_))
if reduced_tys.to_fat_ptr && is_size_pair(from_ty) =>
{
return false;
},
}
// fat ptr -> some struct | some struct -> fat ptr
(ReducedTy::Other(_), _) if reduced_tys.from_fat_ptr => {
@ -78,12 +85,14 @@ pub(super) fn check<'tcx>(
&format!("transmute from `{from_ty_orig}` which has an undefined layout"),
|diag| {
if from_ty_orig.peel_refs() != from_ty.peel_refs() {
diag.note(&format!("the contained type `{from_ty}` has an undefined layout"));
diag.note(&format!(
"the contained type `{from_ty}` has an undefined layout"
));
}
},
);
return true;
},
}
(_, ReducedTy::Other(_)) if reduced_tys.to_fat_ptr => {
span_lint_and_then(
cx,
@ -92,14 +101,18 @@ pub(super) fn check<'tcx>(
&format!("transmute to `{to_ty_orig}` which has an undefined layout"),
|diag| {
if to_ty_orig.peel_refs() != to_ty.peel_refs() {
diag.note(&format!("the contained type `{to_ty}` has an undefined layout"));
diag.note(&format!(
"the contained type `{to_ty}` has an undefined layout"
));
}
},
);
return true;
},
}
(ReducedTy::UnorderedFields(from_ty), ReducedTy::UnorderedFields(to_ty)) if from_ty != to_ty => {
(ReducedTy::UnorderedFields(from_ty), ReducedTy::UnorderedFields(to_ty))
if from_ty != to_ty =>
{
let same_adt_did = if let (ty::Adt(from_def, from_subs), ty::Adt(to_def, to_subs))
= (from_ty.kind(), to_ty.kind())
&& from_def == to_def
@ -126,19 +139,25 @@ pub(super) fn check<'tcx>(
));
} else {
if from_ty_orig.peel_refs() != from_ty {
diag.note(&format!("the contained type `{from_ty}` has an undefined layout"));
diag.note(&format!(
"the contained type `{from_ty}` has an undefined layout"
));
}
if to_ty_orig.peel_refs() != to_ty {
diag.note(&format!("the contained type `{to_ty}` has an undefined layout"));
diag.note(&format!(
"the contained type `{to_ty}` has an undefined layout"
));
}
}
},
);
return true;
},
}
(
ReducedTy::UnorderedFields(from_ty),
ReducedTy::Other(_) | ReducedTy::OrderedFields(..) | ReducedTy::TypeErasure { raw_ptr_only: true },
ReducedTy::Other(_)
| ReducedTy::OrderedFields(..)
| ReducedTy::TypeErasure { raw_ptr_only: true },
) => {
span_lint_and_then(
cx,
@ -147,14 +166,18 @@ pub(super) fn check<'tcx>(
&format!("transmute from `{from_ty_orig}` which has an undefined layout"),
|diag| {
if from_ty_orig.peel_refs() != from_ty {
diag.note(&format!("the contained type `{from_ty}` has an undefined layout"));
diag.note(&format!(
"the contained type `{from_ty}` has an undefined layout"
));
}
},
);
return true;
},
}
(
ReducedTy::Other(_) | ReducedTy::OrderedFields(..) | ReducedTy::TypeErasure { raw_ptr_only: true },
ReducedTy::Other(_)
| ReducedTy::OrderedFields(..)
| ReducedTy::TypeErasure { raw_ptr_only: true },
ReducedTy::UnorderedFields(to_ty),
) => {
span_lint_and_then(
@ -164,19 +187,25 @@ pub(super) fn check<'tcx>(
&format!("transmute into `{to_ty_orig}` which has an undefined layout"),
|diag| {
if to_ty_orig.peel_refs() != to_ty {
diag.note(&format!("the contained type `{to_ty}` has an undefined layout"));
diag.note(&format!(
"the contained type `{to_ty}` has an undefined layout"
));
}
},
);
return true;
},
}
(
ReducedTy::OrderedFields(..) | ReducedTy::Other(_) | ReducedTy::TypeErasure { raw_ptr_only: true },
ReducedTy::OrderedFields(..) | ReducedTy::Other(_) | ReducedTy::TypeErasure { raw_ptr_only: true },
ReducedTy::OrderedFields(..)
| ReducedTy::Other(_)
| ReducedTy::TypeErasure { raw_ptr_only: true },
ReducedTy::OrderedFields(..)
| ReducedTy::Other(_)
| ReducedTy::TypeErasure { raw_ptr_only: true },
)
| (ReducedTy::UnorderedFields(_), ReducedTy::UnorderedFields(_)) => {
break;
},
}
}
}
@ -194,42 +223,38 @@ struct ReducedTys<'tcx> {
}
/// Remove references so long as both types are references.
fn reduce_refs<'tcx>(cx: &LateContext<'tcx>, mut from_ty: Ty<'tcx>, mut to_ty: Ty<'tcx>) -> ReducedTys<'tcx> {
fn reduce_refs<'tcx>(
cx: &LateContext<'tcx>,
mut from_ty: Ty<'tcx>,
mut to_ty: Ty<'tcx>,
) -> ReducedTys<'tcx> {
let mut from_raw_ptr = false;
let mut to_raw_ptr = false;
let (from_fat_ptr, to_fat_ptr) = loop {
break match (from_ty.kind(), to_ty.kind()) {
(
&(ty::Ref(_, from_sub_ty, _) | ty::RawPtr(TypeAndMut { ty: from_sub_ty, .. })),
&(ty::Ref(_, to_sub_ty, _) | ty::RawPtr(TypeAndMut { ty: to_sub_ty, .. })),
) => {
from_raw_ptr = matches!(*from_ty.kind(), ty::RawPtr(_));
from_ty = from_sub_ty;
to_raw_ptr = matches!(*to_ty.kind(), ty::RawPtr(_));
to_ty = to_sub_ty;
continue;
},
(&(ty::Ref(_, unsized_ty, _) | ty::RawPtr(TypeAndMut { ty: unsized_ty, .. })), _)
if !unsized_ty.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env) =>
{
(true, false)
},
(_, &(ty::Ref(_, unsized_ty, _) | ty::RawPtr(TypeAndMut { ty: unsized_ty, .. })))
if !unsized_ty.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env) =>
{
(false, true)
},
_ => (false, false),
let (from_fat_ptr, to_fat_ptr) =
loop {
break match (from_ty.kind(), to_ty.kind()) {
(
&(ty::Ref(_, from_sub_ty, _) | ty::RawPtr(TypeAndMut { ty: from_sub_ty, .. })),
&(ty::Ref(_, to_sub_ty, _) | ty::RawPtr(TypeAndMut { ty: to_sub_ty, .. })),
) => {
from_raw_ptr = matches!(*from_ty.kind(), ty::RawPtr(_));
from_ty = from_sub_ty;
to_raw_ptr = matches!(*to_ty.kind(), ty::RawPtr(_));
to_ty = to_sub_ty;
continue;
}
(
&(ty::Ref(_, unsized_ty, _) | ty::RawPtr(TypeAndMut { ty: unsized_ty, .. })),
_,
) if !unsized_ty.is_sized(cx.tcx, cx.param_env) => (true, false),
(
_,
&(ty::Ref(_, unsized_ty, _) | ty::RawPtr(TypeAndMut { ty: unsized_ty, .. })),
) if !unsized_ty.is_sized(cx.tcx, cx.param_env) => (false, true),
_ => (false, false),
};
};
};
ReducedTys {
from_ty,
to_ty,
from_raw_ptr,
to_raw_ptr,
from_fat_ptr,
to_fat_ptr,
}
ReducedTys { from_ty, to_ty, from_raw_ptr, to_raw_ptr, from_fat_ptr, to_fat_ptr }
}
enum ReducedTy<'tcx> {
@ -252,11 +277,11 @@ fn reduce_ty<'tcx>(cx: &LateContext<'tcx>, mut ty: Ty<'tcx>) -> ReducedTy<'tcx>
return match *ty.kind() {
ty::Array(sub_ty, _) if matches!(sub_ty.kind(), ty::Int(_) | ty::Uint(_)) => {
ReducedTy::TypeErasure { raw_ptr_only: false }
},
}
ty::Array(sub_ty, _) | ty::Slice(sub_ty) => {
ty = sub_ty;
continue;
},
}
ty::Tuple(args) if args.is_empty() => ReducedTy::TypeErasure { raw_ptr_only: false },
ty::Tuple(args) => {
let mut iter = args.iter();
@ -268,7 +293,7 @@ fn reduce_ty<'tcx>(cx: &LateContext<'tcx>, mut ty: Ty<'tcx>) -> ReducedTy<'tcx>
continue;
}
ReducedTy::UnorderedFields(ty)
},
}
ty::Adt(def, substs) if def.is_struct() => {
let mut iter = def
.non_enum_variant()
@ -287,10 +312,12 @@ fn reduce_ty<'tcx>(cx: &LateContext<'tcx>, mut ty: Ty<'tcx>) -> ReducedTy<'tcx>
} else {
ReducedTy::UnorderedFields(ty)
}
},
ty::Adt(def, _) if def.is_enum() && (def.variants().is_empty() || is_c_void(cx, ty)) => {
}
ty::Adt(def, _)
if def.is_enum() && (def.variants().is_empty() || is_c_void(cx, ty)) =>
{
ReducedTy::TypeErasure { raw_ptr_only: false }
},
}
// TODO: Check if the conversion to or from at least one of a union's fields is valid.
ty::Adt(def, _) if def.is_union() => ReducedTy::TypeErasure { raw_ptr_only: false },
ty::Foreign(_) | ty::Param(_) => ReducedTy::TypeErasure { raw_ptr_only: false },
@ -329,7 +356,11 @@ fn same_except_params<'tcx>(subs1: SubstsRef<'tcx>, subs2: SubstsRef<'tcx>) -> b
for (ty1, ty2) in subs1.types().zip(subs2.types()).filter(|(ty1, ty2)| ty1 != ty2) {
match (ty1.kind(), ty2.kind()) {
(ty::Param(_), _) | (_, ty::Param(_)) => (),
(ty::Adt(adt1, subs1), ty::Adt(adt2, subs2)) if adt1 == adt2 && same_except_params(subs1, subs2) => (),
(ty::Adt(adt1, subs1), ty::Adt(adt2, subs2))
if adt1 == adt2 && same_except_params(subs1, subs2) =>
{
()
}
_ => return false,
}
}

View file

@ -9,7 +9,12 @@ use rustc_span::symbol::sym;
use super::{utils, REDUNDANT_ALLOCATION};
pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_>, def_id: DefId) -> bool {
pub(super) fn check(
cx: &LateContext<'_>,
hir_ty: &hir::Ty<'_>,
qpath: &QPath<'_>,
def_id: DefId,
) -> bool {
let mut applicability = Applicability::MaybeIncorrect;
let outer_sym = if Some(def_id) == cx.tcx.lang_items().owned_box() {
"Box"
@ -29,7 +34,12 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_
hir_ty.span,
&format!("usage of `{outer_sym}<{generic_snippet}>`"),
|diag| {
diag.span_suggestion(hir_ty.span, "try", format!("{generic_snippet}"), applicability);
diag.span_suggestion(
hir_ty.span,
"try",
format!("{generic_snippet}"),
applicability,
);
diag.note(&format!(
"`{generic_snippet}` is already a pointer, `{outer_sym}<{generic_snippet}>` allocates a pointer on the heap"
));
@ -55,11 +65,11 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_
// Reallocation of a fat pointer causes it to become thin. `hir_ty_to_ty` is safe to use
// here because `mod.rs` guarantees this lint is only run on types outside of bodies and
// is not run on locals.
if !hir_ty_to_ty(cx.tcx, ty).is_sized(cx.tcx.at(ty.span), cx.param_env) {
if !hir_ty_to_ty(cx.tcx, ty).is_sized(cx.tcx, cx.param_env) {
return false;
}
ty.span
},
}
None => return false,
};
if inner_sym == outer_sym {

View file

@ -40,7 +40,7 @@ pub(super) fn check(
});
let ty_ty = hir_ty_to_ty(cx.tcx, boxed_ty);
if !ty_ty.has_escaping_bound_vars();
if ty_ty.is_sized(cx.tcx.at(ty.span), cx.param_env);
if ty_ty.is_sized(cx.tcx, cx.param_env);
if let Ok(ty_ty_size) = cx.layout_of(ty_ty).map(|l| l.size.bytes());
if ty_ty_size <= box_size_threshold;
then {

View file

@ -18,7 +18,7 @@ use rustc_middle::ty::{
};
use rustc_middle::ty::{GenericArg, GenericArgKind};
use rustc_span::symbol::Ident;
use rustc_span::{sym, Span, Symbol, DUMMY_SP};
use rustc_span::{sym, Span, Symbol};
use rustc_target::abi::{Size, VariantIdx};
use rustc_trait_selection::infer::InferCtxtExt;
use rustc_trait_selection::traits::query::normalize::AtExt;
@ -28,7 +28,7 @@ use crate::{match_def_path, path_res, paths};
// Checks if the given type implements copy.
pub fn is_copy<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool {
ty.is_copy_modulo_regions(cx.tcx.at(DUMMY_SP), cx.param_env)
ty.is_copy_modulo_regions(cx.tcx, cx.param_env)
}
/// This checks whether a given type is known to implement Debug.