Auto merge of #102652 - Dylan-DPC:rollup-6ff8ct8, r=Dylan-DPC

Rollup of 6 pull requests

Successful merges:

 - #101189 (Implement `Ready::into_inner()`)
 - #101642 (Fix in-place collection leak when remaining element destructor panic)
 - #102489 (Normalize substs before resolving instance in `NoopMethodCall` lint)
 - #102559 (Don't ICE when trying to copy unsized value in const prop)
 - #102568 (Lint against nested opaque types that don't satisfy associated type bounds)
 - #102633 (Fix rustdoc ICE in invalid_rust_codeblocks lint)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
This commit is contained in:
bors 2022-10-04 13:04:57 +00:00
commit 02cd79afb8
31 changed files with 467 additions and 58 deletions

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@ -640,11 +640,17 @@ fn copy_op_no_validate(
// avoid force_allocation.
let src = match self.read_immediate_raw(src)? {
Ok(src_val) => {
assert!(!src.layout.is_unsized(), "cannot copy unsized immediates");
assert!(
!dest.layout.is_unsized(),
"the src is sized, so the dest must also be sized"
);
// FIXME(const_prop): Const-prop can possibly evaluate an
// unsized copy operation when it thinks that the type is
// actually sized, due to a trivially false where-clause
// predicate like `where Self: Sized` with `Self = dyn Trait`.
// See #102553 for an example of such a predicate.
if src.layout.is_unsized() {
throw_inval!(SizeOfUnsizedType(src.layout.ty));
}
if dest.layout.is_unsized() {
throw_inval!(SizeOfUnsizedType(dest.layout.ty));
}
assert_eq!(src.layout.size, dest.layout.size);
// Yay, we got a value that we can write directly.
return if layout_compat {

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@ -433,3 +433,7 @@ lint_check_name_unknown_tool = unknown lint tool: `{$tool_name}`
lint_check_name_warning = {$msg}
lint_check_name_deprecated = lint name `{$lint_name}` is deprecated and does not have an effect anymore. Use: {$new_name}
lint_opaque_hidden_inferred_bound = opaque type `{$ty}` does not satisfy its associated type bounds
.specifically = this associated type bound is unsatisfied for `{$proj_ty}`
.suggestion = add this bound

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@ -62,6 +62,7 @@
mod non_fmt_panic;
mod nonstandard_style;
mod noop_method_call;
mod opaque_hidden_inferred_bound;
mod pass_by_value;
mod passes;
mod redundant_semicolon;
@ -93,6 +94,7 @@
use non_fmt_panic::NonPanicFmt;
use nonstandard_style::*;
use noop_method_call::*;
use opaque_hidden_inferred_bound::*;
use pass_by_value::*;
use redundant_semicolon::*;
use traits::*;
@ -223,6 +225,7 @@ macro_rules! late_lint_mod_passes {
EnumIntrinsicsNonEnums: EnumIntrinsicsNonEnums,
InvalidAtomicOrdering: InvalidAtomicOrdering,
NamedAsmLabels: NamedAsmLabels,
OpaqueHiddenInferredBound: OpaqueHiddenInferredBound,
]
);
};

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@ -1,5 +1,4 @@
use crate::context::LintContext;
use crate::rustc_middle::ty::TypeVisitable;
use crate::LateContext;
use crate::LateLintPass;
use rustc_errors::fluent;
@ -46,7 +45,7 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
};
// We only care about method calls corresponding to the `Clone`, `Deref` and `Borrow`
// traits and ignore any other method call.
let (trait_id, did) = match cx.typeck_results().type_dependent_def(expr.hir_id) {
let did = match cx.typeck_results().type_dependent_def(expr.hir_id) {
// Verify we are dealing with a method/associated function.
Some((DefKind::AssocFn, did)) => match cx.tcx.trait_of_item(did) {
// Check that we're dealing with a trait method for one of the traits we care about.
@ -56,21 +55,17 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
Some(sym::Borrow | sym::Clone | sym::Deref)
) =>
{
(trait_id, did)
did
}
_ => return,
},
_ => return,
};
let substs = cx.typeck_results().node_substs(expr.hir_id);
if substs.needs_subst() {
// We can't resolve on types that require monomorphization, so we don't handle them if
// we need to perform substitution.
return;
}
let param_env = cx.tcx.param_env(trait_id);
let substs = cx
.tcx
.normalize_erasing_regions(cx.param_env, cx.typeck_results().node_substs(expr.hir_id));
// Resolve the trait method instance.
let Ok(Some(i)) = ty::Instance::resolve(cx.tcx, param_env, did, substs) else {
let Ok(Some(i)) = ty::Instance::resolve(cx.tcx, cx.param_env, did, substs) else {
return
};
// (Re)check that it implements the noop diagnostic.

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@ -0,0 +1,156 @@
use rustc_hir as hir;
use rustc_infer::infer::TyCtxtInferExt;
use rustc_macros::LintDiagnostic;
use rustc_middle::ty::{self, fold::BottomUpFolder, Ty, TypeFoldable};
use rustc_span::Span;
use rustc_trait_selection::traits;
use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt;
use crate::{LateContext, LateLintPass, LintContext};
declare_lint! {
/// The `opaque_hidden_inferred_bound` lint detects cases in which nested
/// `impl Trait` in associated type bounds are not written generally enough
/// to satisfy the bounds of the associated type.
///
/// ### Explanation
///
/// This functionality was removed in #97346, but then rolled back in #99860
/// because it caused regressions.
///
/// We plan on reintroducing this as a hard error, but in the mean time,
/// this lint serves to warn and suggest fixes for any use-cases which rely
/// on this behavior.
///
/// ### Example
///
/// ```
/// trait Trait {
/// type Assoc: Send;
/// }
///
/// struct Struct;
///
/// impl Trait for Struct {
/// type Assoc = i32;
/// }
///
/// fn test() -> impl Trait<Assoc = impl Sized> {
/// Struct
/// }
/// ```
///
/// {{produces}}
///
/// In this example, `test` declares that the associated type `Assoc` for
/// `impl Trait` is `impl Sized`, which does not satisfy the `Send` bound
/// on the associated type.
///
/// Although the hidden type, `i32` does satisfy this bound, we do not
/// consider the return type to be well-formed with this lint. It can be
/// fixed by changing `impl Sized` into `impl Sized + Send`.
pub OPAQUE_HIDDEN_INFERRED_BOUND,
Warn,
"detects the use of nested `impl Trait` types in associated type bounds that are not general enough"
}
declare_lint_pass!(OpaqueHiddenInferredBound => [OPAQUE_HIDDEN_INFERRED_BOUND]);
impl<'tcx> LateLintPass<'tcx> for OpaqueHiddenInferredBound {
fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'tcx>) {
let hir::ItemKind::OpaqueTy(_) = &item.kind else { return; };
let def_id = item.def_id.def_id.to_def_id();
cx.tcx.infer_ctxt().enter(|ref infcx| {
// For every projection predicate in the opaque type's explicit bounds,
// check that the type that we're assigning actually satisfies the bounds
// of the associated type.
for &(pred, pred_span) in cx.tcx.explicit_item_bounds(def_id) {
// Liberate bound regions in the predicate since we
// don't actually care about lifetimes in this check.
let predicate = cx.tcx.liberate_late_bound_regions(
def_id,
pred.kind(),
);
let ty::PredicateKind::Projection(proj) = predicate else {
continue;
};
// Only check types, since those are the only things that may
// have opaques in them anyways.
let Some(proj_term) = proj.term.ty() else { continue };
let proj_ty =
cx
.tcx
.mk_projection(proj.projection_ty.item_def_id, proj.projection_ty.substs);
// For every instance of the projection type in the bounds,
// replace them with the term we're assigning to the associated
// type in our opaque type.
let proj_replacer = &mut BottomUpFolder {
tcx: cx.tcx,
ty_op: |ty| if ty == proj_ty { proj_term } else { ty },
lt_op: |lt| lt,
ct_op: |ct| ct,
};
// For example, in `impl Trait<Assoc = impl Send>`, for all of the bounds on `Assoc`,
// e.g. `type Assoc: OtherTrait`, replace `<impl Trait as Trait>::Assoc: OtherTrait`
// with `impl Send: OtherTrait`.
for assoc_pred_and_span in cx
.tcx
.bound_explicit_item_bounds(proj.projection_ty.item_def_id)
.transpose_iter()
{
let assoc_pred_span = assoc_pred_and_span.0.1;
let assoc_pred = assoc_pred_and_span
.map_bound(|(pred, _)| *pred)
.subst(cx.tcx, &proj.projection_ty.substs)
.fold_with(proj_replacer);
let Ok(assoc_pred) = traits::fully_normalize(infcx, traits::ObligationCause::dummy(), cx.param_env, assoc_pred) else {
continue;
};
// If that predicate doesn't hold modulo regions (but passed during type-check),
// then we must've taken advantage of the hack in `project_and_unify_types` where
// we replace opaques with inference vars. Emit a warning!
if !infcx.predicate_must_hold_modulo_regions(&traits::Obligation::new(
traits::ObligationCause::dummy(),
cx.param_env,
assoc_pred,
)) {
// If it's a trait bound and an opaque that doesn't satisfy it,
// then we can emit a suggestion to add the bound.
let (suggestion, suggest_span) =
match (proj_term.kind(), assoc_pred.kind().skip_binder()) {
(ty::Opaque(def_id, _), ty::PredicateKind::Trait(trait_pred)) => (
format!(" + {}", trait_pred.print_modifiers_and_trait_path()),
Some(cx.tcx.def_span(def_id).shrink_to_hi()),
),
_ => (String::new(), None),
};
cx.emit_spanned_lint(
OPAQUE_HIDDEN_INFERRED_BOUND,
pred_span,
OpaqueHiddenInferredBoundLint {
ty: cx.tcx.mk_opaque(def_id, ty::InternalSubsts::identity_for_item(cx.tcx, def_id)),
proj_ty: proj_term,
assoc_pred_span,
suggestion,
suggest_span,
},
);
}
}
}
});
}
}
#[derive(LintDiagnostic)]
#[diag(lint::opaque_hidden_inferred_bound)]
struct OpaqueHiddenInferredBoundLint<'tcx> {
ty: Ty<'tcx>,
proj_ty: Ty<'tcx>,
#[label(lint::specifically)]
assoc_pred_span: Span,
#[suggestion_verbose(applicability = "machine-applicable", code = "{suggestion}")]
suggest_span: Option<Span>,
suggestion: String,
}

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@ -446,7 +446,9 @@ pub fn in_external_macro(sess: &Session, span: Span) -> bool {
match expn_data.kind {
ExpnKind::Inlined
| ExpnKind::Root
| ExpnKind::Desugaring(DesugaringKind::ForLoop | DesugaringKind::WhileLoop) => false,
| ExpnKind::Desugaring(
DesugaringKind::ForLoop | DesugaringKind::WhileLoop | DesugaringKind::OpaqueTy,
) => false,
ExpnKind::AstPass(_) | ExpnKind::Desugaring(_) => true, // well, it's "external"
ExpnKind::Macro(MacroKind::Bang, _) => {
// Dummy span for the `def_site` means it's an external macro.

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@ -55,6 +55,9 @@
//! This is handled by the [`InPlaceDrop`] guard for sink items (`U`) and by
//! [`vec::IntoIter::forget_allocation_drop_remaining()`] for remaining source items (`T`).
//!
//! If dropping any remaining source item (`T`) panics then [`InPlaceDstBufDrop`] will handle dropping
//! the already collected sink items (`U`) and freeing the allocation.
//!
//! [`vec::IntoIter::forget_allocation_drop_remaining()`]: super::IntoIter::forget_allocation_drop_remaining()
//!
//! # O(1) collect
@ -138,7 +141,7 @@
use core::mem::{self, ManuallyDrop, SizedTypeProperties};
use core::ptr::{self};
use super::{InPlaceDrop, SpecFromIter, SpecFromIterNested, Vec};
use super::{InPlaceDrop, InPlaceDstBufDrop, SpecFromIter, SpecFromIterNested, Vec};
/// Specialization marker for collecting an iterator pipeline into a Vec while reusing the
/// source allocation, i.e. executing the pipeline in place.
@ -191,14 +194,17 @@ impl<T, I> SpecFromIter<T, I> for Vec<T>
);
}
// Drop any remaining values at the tail of the source but prevent drop of the allocation
// itself once IntoIter goes out of scope.
// If the drop panics then we also leak any elements collected into dst_buf.
// The ownership of the allocation and the new `T` values is temporarily moved into `dst_guard`.
// This is safe because `forget_allocation_drop_remaining` immediately forgets the allocation
// before any panic can occur in order to avoid any double free, and then proceeds to drop
// any remaining values at the tail of the source.
//
// Note: This access to the source wouldn't be allowed by the TrustedRandomIteratorNoCoerce
// contract (used by SpecInPlaceCollect below). But see the "O(1) collect" section in the
// module documenttation why this is ok anyway.
let dst_guard = InPlaceDstBufDrop { ptr: dst_buf, len, cap };
src.forget_allocation_drop_remaining();
mem::forget(dst_guard);
let vec = unsafe { Vec::from_raw_parts(dst_buf, len, cap) };

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@ -22,3 +22,18 @@ fn drop(&mut self) {
}
}
}
// A helper struct for in-place collection that drops the destination allocation and elements,
// to avoid leaking them if some other destructor panics.
pub(super) struct InPlaceDstBufDrop<T> {
pub(super) ptr: *mut T,
pub(super) len: usize,
pub(super) cap: usize,
}
impl<T> Drop for InPlaceDstBufDrop<T> {
#[inline]
fn drop(&mut self) {
unsafe { super::Vec::from_raw_parts(self.ptr, self.len, self.cap) };
}
}

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@ -95,13 +95,16 @@ fn as_raw_mut_slice(&mut self) -> *mut [T] {
}
/// Drops remaining elements and relinquishes the backing allocation.
/// This method guarantees it won't panic before relinquishing
/// the backing allocation.
///
/// This is roughly equivalent to the following, but more efficient
///
/// ```
/// # let mut into_iter = Vec::<u8>::with_capacity(10).into_iter();
/// let mut into_iter = std::mem::replace(&mut into_iter, Vec::new().into_iter());
/// (&mut into_iter).for_each(core::mem::drop);
/// unsafe { core::ptr::write(&mut into_iter, Vec::new().into_iter()); }
/// std::mem::forget(into_iter);
/// ```
///
/// This method is used by in-place iteration, refer to the vec::in_place_collect
@ -118,6 +121,8 @@ pub(super) fn forget_allocation_drop_remaining(&mut self) {
self.ptr = self.buf.as_ptr();
self.end = self.buf.as_ptr();
// Dropping the remaining elements can panic, so this needs to be
// done only after updating the other fields.
unsafe {
ptr::drop_in_place(remaining);
}

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@ -125,7 +125,7 @@
mod set_len_on_drop;
#[cfg(not(no_global_oom_handling))]
use self::in_place_drop::InPlaceDrop;
use self::in_place_drop::{InPlaceDrop, InPlaceDstBufDrop};
#[cfg(not(no_global_oom_handling))]
mod in_place_drop;

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@ -1191,48 +1191,53 @@ fn test_from_iter_specialization_panic_during_iteration_drops() {
}
#[test]
fn test_from_iter_specialization_panic_during_drop_leaks() {
static mut DROP_COUNTER: usize = 0;
fn test_from_iter_specialization_panic_during_drop_doesnt_leak() {
static mut DROP_COUNTER_OLD: [usize; 5] = [0; 5];
static mut DROP_COUNTER_NEW: [usize; 2] = [0; 2];
#[derive(Debug)]
enum Droppable {
DroppedTwice(Box<i32>),
PanicOnDrop,
struct Old(usize);
impl Drop for Old {
fn drop(&mut self) {
unsafe {
DROP_COUNTER_OLD[self.0] += 1;
}
impl Drop for Droppable {
fn drop(&mut self) {
match self {
Droppable::DroppedTwice(_) => {
unsafe {
DROP_COUNTER += 1;
}
println!("Dropping!")
}
Droppable::PanicOnDrop => {
if !std::thread::panicking() {
if self.0 == 3 {
panic!();
}
}
}
println!("Dropped Old: {}", self.0);
}
}
let mut to_free: *mut Droppable = core::ptr::null_mut();
let mut cap = 0;
#[derive(Debug)]
struct New(usize);
impl Drop for New {
fn drop(&mut self) {
unsafe {
DROP_COUNTER_NEW[self.0] += 1;
}
println!("Dropped New: {}", self.0);
}
}
let _ = std::panic::catch_unwind(AssertUnwindSafe(|| {
let mut v = vec![Droppable::DroppedTwice(Box::new(123)), Droppable::PanicOnDrop];
to_free = v.as_mut_ptr();
cap = v.capacity();
let _ = v.into_iter().take(0).collect::<Vec<_>>();
let v = vec![Old(0), Old(1), Old(2), Old(3), Old(4)];
let _ = v.into_iter().map(|x| New(x.0)).take(2).collect::<Vec<_>>();
}));
assert_eq!(unsafe { DROP_COUNTER }, 1);
// clean up the leak to keep miri happy
unsafe {
drop(Vec::from_raw_parts(to_free, 0, cap));
}
assert_eq!(unsafe { DROP_COUNTER_OLD[0] }, 1);
assert_eq!(unsafe { DROP_COUNTER_OLD[1] }, 1);
assert_eq!(unsafe { DROP_COUNTER_OLD[2] }, 1);
assert_eq!(unsafe { DROP_COUNTER_OLD[3] }, 1);
assert_eq!(unsafe { DROP_COUNTER_OLD[4] }, 1);
assert_eq!(unsafe { DROP_COUNTER_NEW[0] }, 1);
assert_eq!(unsafe { DROP_COUNTER_NEW[1] }, 1);
}
// regression test for issue #85322. Peekable previously implemented InPlaceIterable,

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@ -24,6 +24,30 @@ fn poll(mut self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<T> {
}
}
impl<T> Ready<T> {
/// Consumes the `Ready`, returning the wrapped value.
///
/// # Panics
///
/// Will panic if this [`Ready`] was already polled to completion.
///
/// # Examples
///
/// ```
/// #![feature(ready_into_inner)]
/// use std::future;
///
/// let a = future::ready(1);
/// assert_eq!(a.into_inner(), 1);
/// ```
#[unstable(feature = "ready_into_inner", issue = "101196")]
#[must_use]
#[inline]
pub fn into_inner(self) -> T {
self.0.expect("Called `into_inner()` on `Ready` after completion")
}
}
/// Creates a future that is immediately ready with a value.
///
/// Futures created through this function are functionally similar to those

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@ -192,8 +192,11 @@ fn fallback_fluent_bundle(&self) -> &rustc_errors::FluentBundle {
impl Emitter for BufferEmitter {
fn emit_diagnostic(&mut self, diag: &Diagnostic) {
let mut buffer = self.buffer.borrow_mut();
// FIXME(davidtwco): need to support translation here eventually
buffer.messages.push(format!("error from rustc: {}", diag.message[0].0.expect_str()));
let fluent_args = self.to_fluent_args(diag.args());
let translated_main_message = self.translate_message(&diag.message[0].0, &fluent_args);
buffer.messages.push(format!("error from rustc: {}", translated_main_message));
if diag.is_error() {
buffer.has_errors = true;
}

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@ -99,3 +99,9 @@ pub fn indent_after_fenced() {}
/// ```
pub fn invalid() {}
//~^^^^ WARNING could not parse code block as Rust code
/// ```
/// fn wook_at_my_beautifuw_bwaces_plz() {);
/// ```
pub fn uwu() {}
//~^^^^ WARNING could not parse code block as Rust code

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@ -150,5 +150,20 @@ help: mark blocks that do not contain Rust code as text
LL | /// ```text
| ++++
warning: 12 warnings emitted
warning: could not parse code block as Rust code
--> $DIR/invalid-syntax.rs:103:5
|
LL | /// ```
| _____^
LL | | /// fn wook_at_my_beautifuw_bwaces_plz() {);
LL | | /// ```
| |_______^
|
= note: error from rustc: mismatched closing delimiter: `)`
help: mark blocks that do not contain Rust code as text
|
LL | /// ```text
| ++++
warning: 13 warnings emitted

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@ -0,0 +1,23 @@
// check-pass
// Checks that the NoopMethodCall lint doesn't call Instance::resolve on unresolved consts
#![feature(generic_const_exprs)]
#![allow(incomplete_features)]
#[derive(Debug, Clone)]
pub struct Aes128CipherKey([u8; Aes128Cipher::KEY_LEN]);
impl Aes128CipherKey {
pub fn new(key: &[u8; Aes128Cipher::KEY_LEN]) -> Self {
Self(key.clone())
}
}
#[derive(Debug, Clone)]
pub struct Aes128Cipher;
impl Aes128Cipher {
const KEY_LEN: usize = 16;
}
fn main() {}

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@ -0,0 +1,24 @@
// compile-flags: --crate-type=lib
// check-pass
pub trait Widget<E> {
fn boxed<'w>(self) -> Box<dyn WidgetDyn<E> + 'w>
where
Self: Sized + 'w;
}
pub trait WidgetDyn<E> {}
impl<T, E> WidgetDyn<E> for T where T: Widget<E> {}
impl<E> Widget<E> for dyn WidgetDyn<E> + '_ {
fn boxed<'w>(self) -> Box<dyn WidgetDyn<E> + 'w>
where
Self: Sized + 'w,
{
// Even though this is illegal to const evaluate, this should never
// trigger an ICE because it can never be called from actual code
// (due to the trivially false where-clause predicate).
Box::new(self)
}
}

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@ -26,6 +26,7 @@ impl<R: Duh, F: FnMut() -> R> Trait for F {
// var to make it uphold the `: Duh` bound on `Trait::Assoc`. The opaque
// type does not implement `Duh`, but if its hidden type does.
fn foo() -> impl Trait<Assoc = Sendable> {
//~^ WARN opaque type `impl Trait<Assoc = Sendable>` does not satisfy its associated type bounds
|| 42
}

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@ -0,0 +1,17 @@
warning: opaque type `impl Trait<Assoc = Sendable>` does not satisfy its associated type bounds
--> $DIR/nested-return-type2-tait.rs:28:24
|
LL | type Assoc: Duh;
| --- this associated type bound is unsatisfied for `Sendable`
...
LL | fn foo() -> impl Trait<Assoc = Sendable> {
| ^^^^^^^^^^^^^^^^
|
= note: `#[warn(opaque_hidden_inferred_bound)]` on by default
help: add this bound
|
LL | type Sendable = impl Send + Duh;
| +++++
warning: 1 warning emitted

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@ -23,6 +23,7 @@ impl<R: Duh, F: FnMut() -> R> Trait for F {
// Lazy TAIT would error out, but we inserted a hack to make it work again,
// keeping backwards compatibility.
fn foo() -> impl Trait<Assoc = impl Send> {
//~^ WARN opaque type `impl Trait<Assoc = impl Send>` does not satisfy its associated type bounds
|| 42
}

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@ -0,0 +1,17 @@
warning: opaque type `impl Trait<Assoc = impl Send>` does not satisfy its associated type bounds
--> $DIR/nested-return-type2.rs:25:24
|
LL | type Assoc: Duh;
| --- this associated type bound is unsatisfied for `impl Send`
...
LL | fn foo() -> impl Trait<Assoc = impl Send> {
| ^^^^^^^^^^^^^^^^^
|
= note: `#[warn(opaque_hidden_inferred_bound)]` on by default
help: add this bound
|
LL | fn foo() -> impl Trait<Assoc = impl Send + Duh> {
| +++++
warning: 1 warning emitted

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@ -17,6 +17,7 @@ impl<F: Duh> Trait for F {
type Sendable = impl Send;
fn foo() -> impl Trait<Assoc = Sendable> {
//~^ WARN opaque type `impl Trait<Assoc = Sendable>` does not satisfy its associated type bounds
42
}

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@ -0,0 +1,17 @@
warning: opaque type `impl Trait<Assoc = Sendable>` does not satisfy its associated type bounds
--> $DIR/nested-return-type3-tait.rs:19:24
|
LL | type Assoc: Duh;
| --- this associated type bound is unsatisfied for `Sendable`
...
LL | fn foo() -> impl Trait<Assoc = Sendable> {
| ^^^^^^^^^^^^^^^^
|
= note: `#[warn(opaque_hidden_inferred_bound)]` on by default
help: add this bound
|
LL | type Sendable = impl Send + Duh;
| +++++
warning: 1 warning emitted

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@ -16,6 +16,7 @@ impl<F: Duh> Trait for F {
type Sendable = impl Send;
type Traitable = impl Trait<Assoc = Sendable>;
//~^ WARN opaque type `Traitable` does not satisfy its associated type bounds
fn foo() -> Traitable {
42

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@ -0,0 +1,17 @@
warning: opaque type `Traitable` does not satisfy its associated type bounds
--> $DIR/nested-return-type3-tait2.rs:18:29
|
LL | type Assoc: Duh;
| --- this associated type bound is unsatisfied for `Sendable`
...
LL | type Traitable = impl Trait<Assoc = Sendable>;
| ^^^^^^^^^^^^^^^^
|
= note: `#[warn(opaque_hidden_inferred_bound)]` on by default
help: add this bound
|
LL | type Sendable = impl Send + Duh;
| +++++
warning: 1 warning emitted

View File

@ -15,6 +15,7 @@ impl<F: Duh> Trait for F {
}
type Traitable = impl Trait<Assoc = impl Send>;
//~^ WARN opaque type `Traitable` does not satisfy its associated type bounds
fn foo() -> Traitable {
42

View File

@ -0,0 +1,17 @@
warning: opaque type `Traitable` does not satisfy its associated type bounds
--> $DIR/nested-return-type3-tait3.rs:17:29
|
LL | type Assoc: Duh;
| --- this associated type bound is unsatisfied for `impl Send`
...
LL | type Traitable = impl Trait<Assoc = impl Send>;
| ^^^^^^^^^^^^^^^^^
|
= note: `#[warn(opaque_hidden_inferred_bound)]` on by default
help: add this bound
|
LL | type Traitable = impl Trait<Assoc = impl Send + Duh>;
| +++++
warning: 1 warning emitted

View File

@ -13,6 +13,7 @@ impl<F: Duh> Trait for F {
}
fn foo() -> impl Trait<Assoc = impl Send> {
//~^ WARN opaque type `impl Trait<Assoc = impl Send>` does not satisfy its associated type bounds
42
}

View File

@ -0,0 +1,17 @@
warning: opaque type `impl Trait<Assoc = impl Send>` does not satisfy its associated type bounds
--> $DIR/nested-return-type3.rs:15:24
|
LL | type Assoc: Duh;
| --- this associated type bound is unsatisfied for `impl Send`
...
LL | fn foo() -> impl Trait<Assoc = impl Send> {
| ^^^^^^^^^^^^^^^^^
|
= note: `#[warn(opaque_hidden_inferred_bound)]` on by default
help: add this bound
|
LL | fn foo() -> impl Trait<Assoc = impl Send + Duh> {
| +++++
warning: 1 warning emitted

View File

@ -46,6 +46,7 @@ fn main() {
fn generic<T>(non_clone_type: &PlainType<T>) {
non_clone_type.clone();
//~^ WARNING call to `.clone()` on a reference in this situation does nothing
}
fn non_generic(non_clone_type: &PlainType<u32>) {

View File

@ -28,12 +28,20 @@ LL | let non_borrow_type_borrow: &PlainType<u32> = non_borrow_type.borrow();
= note: the type `&PlainType<u32>` which `borrow` is being called on is the same as the type returned from `borrow`, so the method call does not do anything and can be removed
warning: call to `.clone()` on a reference in this situation does nothing
--> $DIR/noop-method-call.rs:52:19
--> $DIR/noop-method-call.rs:48:19
|
LL | non_clone_type.clone();
| ^^^^^^^^ unnecessary method call
|
= note: the type `&PlainType<T>` which `clone` is being called on is the same as the type returned from `clone`, so the method call does not do anything and can be removed
warning: call to `.clone()` on a reference in this situation does nothing
--> $DIR/noop-method-call.rs:53:19
|
LL | non_clone_type.clone();
| ^^^^^^^^ unnecessary method call
|
= note: the type `&PlainType<u32>` which `clone` is being called on is the same as the type returned from `clone`, so the method call does not do anything and can be removed
warning: 4 warnings emitted
warning: 5 warnings emitted