Auto merge of #64535 - Centril:rollup-wiyxagi, r=Centril
Rollup of 6 pull requests
Successful merges:
- #64085 (Tweak unsatisfied HRTB errors)
- #64380 (Update bundled OpenSSL to 1.1.1d)
- #64416 (Various refactorings to clean up nll diagnostics)
- #64500 (Various `ObligationForest` improvements)
- #64530 (Elide lifetimes in `Pin<&(mut) Self>`)
- #64531 (Use shorthand syntax in the self parameter of methods of Pin)
Failed merges:
r? @ghost
diff --git a/Cargo.lock b/Cargo.lock
index 0fe3138..b717460 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2182,9 +2182,9 @@
[[package]]
name = "openssl-src"
-version = "111.3.0+1.1.1c"
+version = "111.6.0+1.1.1d"
source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "53ed5f31d294bdf5f7a4ba0a206c2754b0f60e9a63b7e3076babc5317873c797"
+checksum = "b9c2da1de8a7a3f860919c01540b03a6db16de042405a8a07a5e9d0b4b825d9c"
dependencies = [
"cc",
]
diff --git a/src/libcore/option.rs b/src/libcore/option.rs
index 79bd04b..5569d99 100644
--- a/src/libcore/option.rs
+++ b/src/libcore/option.rs
@@ -295,7 +295,7 @@
/// [`Pin`]: ../pin/struct.Pin.html
#[inline]
#[stable(feature = "pin", since = "1.33.0")]
- pub fn as_pin_ref<'a>(self: Pin<&'a Option<T>>) -> Option<Pin<&'a T>> {
+ pub fn as_pin_ref(self: Pin<&Self>) -> Option<Pin<&T>> {
unsafe {
Pin::get_ref(self).as_ref().map(|x| Pin::new_unchecked(x))
}
@@ -306,7 +306,7 @@
/// [`Pin`]: ../pin/struct.Pin.html
#[inline]
#[stable(feature = "pin", since = "1.33.0")]
- pub fn as_pin_mut<'a>(self: Pin<&'a mut Option<T>>) -> Option<Pin<&'a mut T>> {
+ pub fn as_pin_mut(self: Pin<&mut Self>) -> Option<Pin<&mut T>> {
unsafe {
Pin::get_unchecked_mut(self).as_mut().map(|x| Pin::new_unchecked(x))
}
diff --git a/src/libcore/pin.rs b/src/libcore/pin.rs
index 1080fd3..be59e83 100644
--- a/src/libcore/pin.rs
+++ b/src/libcore/pin.rs
@@ -233,7 +233,7 @@
//! # type Field = i32;
//! # struct Struct { field: Field }
//! impl Struct {
-//! fn pin_get_field<'a>(self: Pin<&'a mut Self>) -> &'a mut Field {
+//! fn pin_get_field(self: Pin<&mut Self>) -> &mut Field {
//! // This is okay because `field` is never considered pinned.
//! unsafe { &mut self.get_unchecked_mut().field }
//! }
@@ -257,7 +257,7 @@
//! # type Field = i32;
//! # struct Struct { field: Field }
//! impl Struct {
-//! fn pin_get_field<'a>(self: Pin<&'a mut Self>) -> Pin<&'a mut Field> {
+//! fn pin_get_field(self: Pin<&mut Self>) -> Pin<&mut Field> {
//! // This is okay because `field` is pinned when `self` is.
//! unsafe { self.map_unchecked_mut(|s| &mut s.field) }
//! }
@@ -549,7 +549,7 @@
/// ruled out by the contract of `Pin::new_unchecked`.
#[stable(feature = "pin", since = "1.33.0")]
#[inline(always)]
- pub fn as_ref(self: &Pin<P>) -> Pin<&P::Target> {
+ pub fn as_ref(&self) -> Pin<&P::Target> {
unsafe { Pin::new_unchecked(&*self.pointer) }
}
@@ -586,7 +586,7 @@
/// ruled out by the contract of `Pin::new_unchecked`.
#[stable(feature = "pin", since = "1.33.0")]
#[inline(always)]
- pub fn as_mut(self: &mut Pin<P>) -> Pin<&mut P::Target> {
+ pub fn as_mut(&mut self) -> Pin<&mut P::Target> {
unsafe { Pin::new_unchecked(&mut *self.pointer) }
}
@@ -596,7 +596,7 @@
/// run before being overwritten, so no pinning guarantee is violated.
#[stable(feature = "pin", since = "1.33.0")]
#[inline(always)]
- pub fn set(self: &mut Pin<P>, value: P::Target)
+ pub fn set(&mut self, value: P::Target)
where
P::Target: Sized,
{
@@ -621,7 +621,7 @@
///
/// [`pin` module]: ../../std/pin/index.html#projections-and-structural-pinning
#[stable(feature = "pin", since = "1.33.0")]
- pub unsafe fn map_unchecked<U, F>(self: Pin<&'a T>, func: F) -> Pin<&'a U> where
+ pub unsafe fn map_unchecked<U, F>(self, func: F) -> Pin<&'a U> where
F: FnOnce(&T) -> &U,
{
let pointer = &*self.pointer;
@@ -648,7 +648,7 @@
/// ["pinning projections"]: ../../std/pin/index.html#projections-and-structural-pinning
#[stable(feature = "pin", since = "1.33.0")]
#[inline(always)]
- pub fn get_ref(self: Pin<&'a T>) -> &'a T {
+ pub fn get_ref(self) -> &'a T {
self.pointer
}
}
@@ -657,7 +657,7 @@
/// Converts this `Pin<&mut T>` into a `Pin<&T>` with the same lifetime.
#[stable(feature = "pin", since = "1.33.0")]
#[inline(always)]
- pub fn into_ref(self: Pin<&'a mut T>) -> Pin<&'a T> {
+ pub fn into_ref(self) -> Pin<&'a T> {
Pin { pointer: self.pointer }
}
@@ -672,7 +672,7 @@
/// with the same lifetime as the original `Pin`.
#[stable(feature = "pin", since = "1.33.0")]
#[inline(always)]
- pub fn get_mut(self: Pin<&'a mut T>) -> &'a mut T
+ pub fn get_mut(self) -> &'a mut T
where T: Unpin,
{
self.pointer
@@ -690,7 +690,7 @@
/// instead.
#[stable(feature = "pin", since = "1.33.0")]
#[inline(always)]
- pub unsafe fn get_unchecked_mut(self: Pin<&'a mut T>) -> &'a mut T {
+ pub unsafe fn get_unchecked_mut(self) -> &'a mut T {
self.pointer
}
@@ -710,7 +710,7 @@
///
/// [`pin` module]: ../../std/pin/index.html#projections-and-structural-pinning
#[stable(feature = "pin", since = "1.33.0")]
- pub unsafe fn map_unchecked_mut<U, F>(self: Pin<&'a mut T>, func: F) -> Pin<&'a mut U> where
+ pub unsafe fn map_unchecked_mut<U, F>(self, func: F) -> Pin<&'a mut U> where
F: FnOnce(&mut T) -> &mut U,
{
let pointer = Pin::get_unchecked_mut(self);
diff --git a/src/librustc/infer/error_reporting/nice_region_error/placeholder_error.rs b/src/librustc/infer/error_reporting/nice_region_error/placeholder_error.rs
index b4fb018..19bd38b 100644
--- a/src/librustc/infer/error_reporting/nice_region_error/placeholder_error.rs
+++ b/src/librustc/infer/error_reporting/nice_region_error/placeholder_error.rs
@@ -192,23 +192,28 @@
vid, sub_placeholder, sup_placeholder, trait_def_id, expected_substs, actual_substs
);
- let mut err = self.tcx().sess.struct_span_err(
- cause.span(self.tcx()),
- &format!(
- "implementation of `{}` is not general enough",
- self.tcx().def_path_str(trait_def_id),
- ),
+ let span = cause.span(self.tcx());
+ let msg = format!(
+ "implementation of `{}` is not general enough",
+ self.tcx().def_path_str(trait_def_id),
+ );
+ let mut err = self.tcx().sess.struct_span_err(span, &msg);
+ err.span_label(
+ self.tcx().def_span(trait_def_id),
+ format!("trait `{}` defined here", self.tcx().def_path_str(trait_def_id)),
);
- match cause.code {
- ObligationCauseCode::ItemObligation(def_id) => {
- err.note(&format!(
- "Due to a where-clause on `{}`,",
- self.tcx().def_path_str(def_id),
- ));
- }
- _ => (),
- }
+ let leading_ellipsis = if let ObligationCauseCode::ItemObligation(def_id) = cause.code {
+ err.span_label(span, "doesn't satisfy where-clause");
+ err.span_label(
+ self.tcx().def_span(def_id),
+ &format!("due to a where-clause on `{}`...", self.tcx().def_path_str(def_id)),
+ );
+ true
+ } else {
+ err.span_label(span, &msg);
+ false
+ };
let expected_trait_ref = self.infcx.resolve_vars_if_possible(&ty::TraitRef {
def_id: trait_def_id,
@@ -295,6 +300,7 @@
expected_has_vid,
actual_has_vid,
any_self_ty_has_vid,
+ leading_ellipsis,
);
err
@@ -318,6 +324,7 @@
expected_has_vid: Option<usize>,
actual_has_vid: Option<usize>,
any_self_ty_has_vid: bool,
+ leading_ellipsis: bool,
) {
// HACK(eddyb) maybe move this in a more central location.
#[derive(Copy, Clone)]
@@ -392,13 +399,15 @@
let mut note = if passive_voice {
format!(
- "`{}` would have to be implemented for the type `{}`",
+ "{}`{}` would have to be implemented for the type `{}`",
+ if leading_ellipsis { "..." } else { "" },
expected_trait_ref,
expected_trait_ref.map(|tr| tr.self_ty()),
)
} else {
format!(
- "`{}` must implement `{}`",
+ "{}`{}` must implement `{}`",
+ if leading_ellipsis { "..." } else { "" },
expected_trait_ref.map(|tr| tr.self_ty()),
expected_trait_ref,
)
@@ -407,20 +416,20 @@
match (has_sub, has_sup) {
(Some(n1), Some(n2)) => {
let _ = write!(note,
- ", for any two lifetimes `'{}` and `'{}`",
+ ", for any two lifetimes `'{}` and `'{}`...",
std::cmp::min(n1, n2),
std::cmp::max(n1, n2),
);
}
(Some(n), _) | (_, Some(n)) => {
let _ = write!(note,
- ", for any lifetime `'{}`",
+ ", for any lifetime `'{}`...",
n,
);
}
(None, None) => if let Some(n) = expected_has_vid {
let _ = write!(note,
- ", for some specific lifetime `'{}`",
+ ", for some specific lifetime `'{}`...",
n,
);
},
@@ -439,13 +448,13 @@
let mut note = if passive_voice {
format!(
- "but `{}` is actually implemented for the type `{}`",
+ "...but `{}` is actually implemented for the type `{}`",
actual_trait_ref,
actual_trait_ref.map(|tr| tr.self_ty()),
)
} else {
format!(
- "but `{}` actually implements `{}`",
+ "...but `{}` actually implements `{}`",
actual_trait_ref.map(|tr| tr.self_ty()),
actual_trait_ref,
)
diff --git a/src/librustc_data_structures/indexed_vec.rs b/src/librustc_data_structures/indexed_vec.rs
index 6f40d05..6e80b48 100644
--- a/src/librustc_data_structures/indexed_vec.rs
+++ b/src/librustc_data_structures/indexed_vec.rs
@@ -149,7 +149,7 @@
#[inline]
$v const unsafe fn from_u32_unchecked(value: u32) -> Self {
- unsafe { $type { private: value } }
+ $type { private: value }
}
/// Extracts the value of this index as an integer.
diff --git a/src/librustc_data_structures/obligation_forest/graphviz.rs b/src/librustc_data_structures/obligation_forest/graphviz.rs
index a0363e1..b2120b1 100644
--- a/src/librustc_data_structures/obligation_forest/graphviz.rs
+++ b/src/librustc_data_structures/obligation_forest/graphviz.rs
@@ -74,9 +74,9 @@
.flat_map(|i| {
let node = &self.nodes[i];
- node.parent.iter().map(|p| p.get())
- .chain(node.dependents.iter().map(|p| p.get()))
- .map(move |p| (p, i))
+ node.parent.iter()
+ .chain(node.dependents.iter())
+ .map(move |p| (p.index(), i))
})
.collect()
}
diff --git a/src/librustc_data_structures/obligation_forest/mod.rs b/src/librustc_data_structures/obligation_forest/mod.rs
index 6c52e62..189506b 100644
--- a/src/librustc_data_structures/obligation_forest/mod.rs
+++ b/src/librustc_data_structures/obligation_forest/mod.rs
@@ -9,7 +9,7 @@
//! `ObligationForest` supports two main public operations (there are a
//! few others not discussed here):
//!
-//! 1. Add a new root obligations (`push_tree`).
+//! 1. Add a new root obligations (`register_obligation`).
//! 2. Process the pending obligations (`process_obligations`).
//!
//! When a new obligation `N` is added, it becomes the root of an
@@ -20,13 +20,13 @@
//! with every pending obligation (so that will include `N`, the first
//! time). The callback also receives a (mutable) reference to the
//! per-tree state `T`. The callback should process the obligation `O`
-//! that it is given and return one of three results:
+//! that it is given and return a `ProcessResult`:
//!
-//! - `Ok(None)` -> ambiguous result. Obligation was neither a success
+//! - `Unchanged` -> ambiguous result. Obligation was neither a success
//! nor a failure. It is assumed that further attempts to process the
//! obligation will yield the same result unless something in the
//! surrounding environment changes.
-//! - `Ok(Some(C))` - the obligation was *shallowly successful*. The
+//! - `Changed(C)` - the obligation was *shallowly successful*. The
//! vector `C` is a list of subobligations. The meaning of this is that
//! `O` was successful on the assumption that all the obligations in `C`
//! are also successful. Therefore, `O` is only considered a "true"
@@ -34,7 +34,7 @@
//! state and the obligations in `C` become the new pending
//! obligations. They will be processed the next time you call
//! `process_obligations`.
-//! - `Err(E)` -> obligation failed with error `E`. We will collect this
+//! - `Error(E)` -> obligation failed with error `E`. We will collect this
//! error and return it from `process_obligations`, along with the
//! "backtrace" of obligations (that is, the list of obligations up to
//! and including the root of the failed obligation). No further
@@ -47,55 +47,50 @@
//! - `completed`: a list of obligations where processing was fully
//! completed without error (meaning that all transitive subobligations
//! have also been completed). So, for example, if the callback from
-//! `process_obligations` returns `Ok(Some(C))` for some obligation `O`,
+//! `process_obligations` returns `Changed(C)` for some obligation `O`,
//! then `O` will be considered completed right away if `C` is the
//! empty vector. Otherwise it will only be considered completed once
//! all the obligations in `C` have been found completed.
//! - `errors`: a list of errors that occurred and associated backtraces
//! at the time of error, which can be used to give context to the user.
//! - `stalled`: if true, then none of the existing obligations were
-//! *shallowly successful* (that is, no callback returned `Ok(Some(_))`).
+//! *shallowly successful* (that is, no callback returned `Changed(_)`).
//! This implies that all obligations were either errors or returned an
//! ambiguous result, which means that any further calls to
//! `process_obligations` would simply yield back further ambiguous
//! results. This is used by the `FulfillmentContext` to decide when it
//! has reached a steady state.
//!
-//! #### Snapshots
-//!
-//! The `ObligationForest` supports a limited form of snapshots; see
-//! `start_snapshot`, `commit_snapshot`, and `rollback_snapshot`. In
-//! particular, you can use a snapshot to roll back new root
-//! obligations. However, it is an error to attempt to
-//! `process_obligations` during a snapshot.
-//!
//! ### Implementation details
//!
//! For the most part, comments specific to the implementation are in the
//! code. This file only contains a very high-level overview. Basically,
//! the forest is stored in a vector. Each element of the vector is a node
-//! in some tree. Each node in the vector has the index of an (optional)
-//! parent and (for convenience) its root (which may be itself). It also
-//! has a current state, described by `NodeState`. After each
-//! processing step, we compress the vector to remove completed and error
-//! nodes, which aren't needed anymore.
+//! in some tree. Each node in the vector has the index of its dependents,
+//! including the first dependent which is known as the parent. It also
+//! has a current state, described by `NodeState`. After each processing
+//! step, we compress the vector to remove completed and error nodes, which
+//! aren't needed anymore.
use crate::fx::{FxHashMap, FxHashSet};
+use crate::indexed_vec::Idx;
+use crate::newtype_index;
-use std::cell::Cell;
+use std::cell::{Cell, RefCell};
use std::collections::hash_map::Entry;
use std::fmt::Debug;
use std::hash;
use std::marker::PhantomData;
-mod node_index;
-use self::node_index::NodeIndex;
-
mod graphviz;
#[cfg(test)]
mod tests;
+newtype_index! {
+ pub struct NodeIndex { .. }
+}
+
pub trait ForestObligation : Clone + Debug {
type Predicate : Clone + hash::Hash + Eq + Debug;
@@ -148,18 +143,22 @@
/// At the end of processing, those nodes will be removed by a
/// call to `compress`.
///
- /// At all times we maintain the invariant that every node appears
- /// at a higher index than its parent. This is needed by the
- /// backtrace iterator (which uses `split_at`).
+ /// Ideally, this would be an `IndexVec<NodeIndex, Node<O>>`. But that is
+ /// slower, because this vector is accessed so often that the
+ /// `u32`-to-`usize` conversions required for accesses are significant.
nodes: Vec<Node<O>>,
/// A cache of predicates that have been successfully completed.
done_cache: FxHashSet<O::Predicate>,
- /// An cache of the nodes in `nodes`, indexed by predicate.
+ /// A cache of the nodes in `nodes`, indexed by predicate. Unfortunately,
+ /// its contents are not guaranteed to match those of `nodes`. See the
+ /// comments in `process_obligation` for details.
waiting_cache: FxHashMap<O::Predicate, NodeIndex>,
- scratch: Option<Vec<usize>>,
+ /// A scratch vector reused in various operations, to avoid allocating new
+ /// vectors.
+ scratch: RefCell<Vec<usize>>,
obligation_tree_id_generator: ObligationTreeIdGenerator,
@@ -178,19 +177,41 @@
obligation: O,
state: Cell<NodeState>,
- /// The parent of a node - the original obligation of
- /// which it is a subobligation. Except for error reporting,
- /// it is just like any member of `dependents`.
+ /// The parent of a node - the original obligation of which it is a
+ /// subobligation. Except for error reporting, it is just like any member
+ /// of `dependents`.
+ ///
+ /// Unlike `ObligationForest::nodes`, this uses `NodeIndex` rather than
+ /// `usize` for the index, because keeping the size down is more important
+ /// than the cost of converting to a `usize` for indexing.
parent: Option<NodeIndex>,
- /// Obligations that depend on this obligation for their
- /// completion. They must all be in a non-pending state.
+ /// Obligations that depend on this obligation for their completion. They
+ /// must all be in a non-pending state.
+ ///
+ /// This uses `NodeIndex` for the same reason as `parent`.
dependents: Vec<NodeIndex>,
/// Identifier of the obligation tree to which this node belongs.
obligation_tree_id: ObligationTreeId,
}
+impl<O> Node<O> {
+ fn new(
+ parent: Option<NodeIndex>,
+ obligation: O,
+ obligation_tree_id: ObligationTreeId
+ ) -> Node<O> {
+ Node {
+ obligation,
+ state: Cell::new(NodeState::Pending),
+ parent,
+ dependents: vec![],
+ obligation_tree_id,
+ }
+ }
+}
+
/// The state of one node in some tree within the forest. This
/// represents the current state of processing for the obligation (of
/// type `O`) associated with this node.
@@ -262,7 +283,7 @@
nodes: vec![],
done_cache: Default::default(),
waiting_cache: Default::default(),
- scratch: Some(vec![]),
+ scratch: RefCell::new(vec![]),
obligation_tree_id_generator: (0..).map(ObligationTreeId),
error_cache: Default::default(),
}
@@ -275,14 +296,12 @@
}
/// Registers an obligation.
- ///
- /// This CAN be done in a snapshot
pub fn register_obligation(&mut self, obligation: O) {
// Ignore errors here - there is no guarantee of success.
let _ = self.register_obligation_at(obligation, None);
}
- // returns Err(()) if we already know this obligation failed.
+ // Returns Err(()) if we already know this obligation failed.
fn register_obligation_at(&mut self, obligation: O, parent: Option<NodeIndex>)
-> Result<(), ()>
{
@@ -294,15 +313,16 @@
Entry::Occupied(o) => {
debug!("register_obligation_at({:?}, {:?}) - duplicate of {:?}!",
obligation, parent, o.get());
- let node = &mut self.nodes[o.get().get()];
- if let Some(parent) = parent {
+ let node = &mut self.nodes[o.get().index()];
+ if let Some(parent_index) = parent {
// If the node is already in `waiting_cache`, it's already
// been marked with a parent. (It's possible that parent
// has been cleared by `apply_rewrites`, though.) So just
// dump `parent` into `node.dependents`... unless it's
// already in `node.dependents` or `node.parent`.
- if !node.dependents.contains(&parent) && Some(parent) != node.parent {
- node.dependents.push(parent);
+ if !node.dependents.contains(&parent_index) &&
+ Some(parent_index) != node.parent {
+ node.dependents.push(parent_index);
}
}
if let NodeState::Error = node.state.get() {
@@ -316,9 +336,8 @@
obligation, parent, self.nodes.len());
let obligation_tree_id = match parent {
- Some(p) => {
- let parent_node = &self.nodes[p.get()];
- parent_node.obligation_tree_id
+ Some(parent_index) => {
+ self.nodes[parent_index.index()].obligation_tree_id
}
None => self.obligation_tree_id_generator.next().unwrap()
};
@@ -342,13 +361,11 @@
}
/// Converts all remaining obligations to the given error.
- ///
- /// This cannot be done during a snapshot.
pub fn to_errors<E: Clone>(&mut self, error: E) -> Vec<Error<O, E>> {
let mut errors = vec![];
- for index in 0..self.nodes.len() {
- if let NodeState::Pending = self.nodes[index].state.get() {
- let backtrace = self.error_at(index);
+ for (i, node) in self.nodes.iter().enumerate() {
+ if let NodeState::Pending = node.state.get() {
+ let backtrace = self.error_at(i);
errors.push(Error {
error: error.clone(),
backtrace,
@@ -373,7 +390,6 @@
fn insert_into_error_cache(&mut self, node_index: usize) {
let node = &self.nodes[node_index];
-
self.error_cache
.entry(node.obligation_tree_id)
.or_default()
@@ -393,16 +409,22 @@
let mut errors = vec![];
let mut stalled = true;
- for index in 0..self.nodes.len() {
- debug!("process_obligations: node {} == {:?}", index, self.nodes[index]);
+ for i in 0..self.nodes.len() {
+ let node = &mut self.nodes[i];
- let result = match self.nodes[index] {
- Node { ref state, ref mut obligation, .. } if state.get() == NodeState::Pending =>
- processor.process_obligation(obligation),
+ debug!("process_obligations: node {} == {:?}", i, node);
+
+ // `processor.process_obligation` can modify the predicate within
+ // `node.obligation`, and that predicate is the key used for
+ // `self.waiting_cache`. This means that `self.waiting_cache` can
+ // get out of sync with `nodes`. It's not very common, but it does
+ // happen, and code in `compress` has to allow for it.
+ let result = match node.state.get() {
+ NodeState::Pending => processor.process_obligation(&mut node.obligation),
_ => continue
};
- debug!("process_obligations: node {} got result {:?}", index, result);
+ debug!("process_obligations: node {} got result {:?}", i, result);
match result {
ProcessResult::Unchanged => {
@@ -411,23 +433,23 @@
ProcessResult::Changed(children) => {
// We are not (yet) stalled.
stalled = false;
- self.nodes[index].state.set(NodeState::Success);
+ node.state.set(NodeState::Success);
for child in children {
let st = self.register_obligation_at(
child,
- Some(NodeIndex::new(index))
+ Some(NodeIndex::new(i))
);
if let Err(()) = st {
- // error already reported - propagate it
+ // Error already reported - propagate it
// to our node.
- self.error_at(index);
+ self.error_at(i);
}
}
}
ProcessResult::Error(err) => {
stalled = false;
- let backtrace = self.error_at(index);
+ let backtrace = self.error_at(i);
errors.push(Error {
error: err,
backtrace,
@@ -448,8 +470,6 @@
self.mark_as_waiting();
self.process_cycles(processor);
-
- // Now we have to compress the result
let completed = self.compress(do_completed);
debug!("process_obligations: complete");
@@ -465,97 +485,92 @@
/// report all cycles between them. This should be called
/// after `mark_as_waiting` marks all nodes with pending
/// subobligations as NodeState::Waiting.
- fn process_cycles<P>(&mut self, processor: &mut P)
+ fn process_cycles<P>(&self, processor: &mut P)
where P: ObligationProcessor<Obligation=O>
{
- let mut stack = self.scratch.take().unwrap();
+ let mut stack = self.scratch.replace(vec![]);
debug_assert!(stack.is_empty());
debug!("process_cycles()");
- for index in 0..self.nodes.len() {
+ for (i, node) in self.nodes.iter().enumerate() {
// For rustc-benchmarks/inflate-0.1.0 this state test is extremely
// hot and the state is almost always `Pending` or `Waiting`. It's
// a win to handle the no-op cases immediately to avoid the cost of
// the function call.
- let state = self.nodes[index].state.get();
- match state {
+ match node.state.get() {
NodeState::Waiting | NodeState::Pending | NodeState::Done | NodeState::Error => {},
- _ => self.find_cycles_from_node(&mut stack, processor, index),
+ _ => self.find_cycles_from_node(&mut stack, processor, i),
}
}
debug!("process_cycles: complete");
debug_assert!(stack.is_empty());
- self.scratch = Some(stack);
+ self.scratch.replace(stack);
}
- fn find_cycles_from_node<P>(&self, stack: &mut Vec<usize>,
- processor: &mut P, index: usize)
+ fn find_cycles_from_node<P>(&self, stack: &mut Vec<usize>, processor: &mut P, i: usize)
where P: ObligationProcessor<Obligation=O>
{
- let node = &self.nodes[index];
- let state = node.state.get();
- match state {
+ let node = &self.nodes[i];
+ match node.state.get() {
NodeState::OnDfsStack => {
- let index =
- stack.iter().rposition(|n| *n == index).unwrap();
- processor.process_backedge(stack[index..].iter().map(GetObligation(&self.nodes)),
+ let i = stack.iter().rposition(|n| *n == i).unwrap();
+ processor.process_backedge(stack[i..].iter().map(GetObligation(&self.nodes)),
PhantomData);
}
NodeState::Success => {
node.state.set(NodeState::OnDfsStack);
- stack.push(index);
- for dependent in node.parent.iter().chain(node.dependents.iter()) {
- self.find_cycles_from_node(stack, processor, dependent.get());
+ stack.push(i);
+ for index in node.parent.iter().chain(node.dependents.iter()) {
+ self.find_cycles_from_node(stack, processor, index.index());
}
stack.pop();
node.state.set(NodeState::Done);
},
NodeState::Waiting | NodeState::Pending => {
- // this node is still reachable from some pending node. We
+ // This node is still reachable from some pending node. We
// will get to it when they are all processed.
}
NodeState::Done | NodeState::Error => {
- // already processed that node
+ // Already processed that node.
}
};
}
/// Returns a vector of obligations for `p` and all of its
/// ancestors, putting them into the error state in the process.
- fn error_at(&mut self, p: usize) -> Vec<O> {
- let mut error_stack = self.scratch.take().unwrap();
+ fn error_at(&self, mut i: usize) -> Vec<O> {
+ let mut error_stack = self.scratch.replace(vec![]);
let mut trace = vec![];
- let mut n = p;
loop {
- self.nodes[n].state.set(NodeState::Error);
- trace.push(self.nodes[n].obligation.clone());
- error_stack.extend(self.nodes[n].dependents.iter().map(|x| x.get()));
+ let node = &self.nodes[i];
+ node.state.set(NodeState::Error);
+ trace.push(node.obligation.clone());
+ error_stack.extend(node.dependents.iter().map(|index| index.index()));
- // loop to the parent
- match self.nodes[n].parent {
- Some(q) => n = q.get(),
+ // Loop to the parent.
+ match node.parent {
+ Some(parent_index) => i = parent_index.index(),
None => break
}
}
while let Some(i) = error_stack.pop() {
- match self.nodes[i].state.get() {
+ let node = &self.nodes[i];
+ match node.state.get() {
NodeState::Error => continue,
- _ => self.nodes[i].state.set(NodeState::Error),
+ _ => node.state.set(NodeState::Error),
}
- let node = &self.nodes[i];
-
error_stack.extend(
- node.parent.iter().chain(node.dependents.iter()).map(|x| x.get())
+ node.parent.iter().chain(node.dependents.iter()).map(|index| index.index())
);
}
- self.scratch = Some(error_stack);
+ self.scratch.replace(error_stack);
trace
}
@@ -563,7 +578,7 @@
#[inline(always)]
fn inlined_mark_neighbors_as_waiting_from(&self, node: &Node<O>) {
for dependent in node.parent.iter().chain(node.dependents.iter()) {
- self.mark_as_waiting_from(&self.nodes[dependent.get()]);
+ self.mark_as_waiting_from(&self.nodes[dependent.index()]);
}
}
@@ -609,7 +624,7 @@
#[inline(never)]
fn compress(&mut self, do_completed: DoCompleted) -> Option<Vec<O>> {
let nodes_len = self.nodes.len();
- let mut node_rewrites: Vec<_> = self.scratch.take().unwrap();
+ let mut node_rewrites: Vec<_> = self.scratch.replace(vec![]);
node_rewrites.extend(0..nodes_len);
let mut dead_nodes = 0;
@@ -620,7 +635,8 @@
// self.nodes[i - dead_nodes..i] are all dead
// self.nodes[i..] are unchanged
for i in 0..self.nodes.len() {
- match self.nodes[i].state.get() {
+ let node = &self.nodes[i];
+ match node.state.get() {
NodeState::Pending | NodeState::Waiting => {
if dead_nodes > 0 {
self.nodes.swap(i, i - dead_nodes);
@@ -628,13 +644,16 @@
}
}
NodeState::Done => {
- // Avoid cloning the key (predicate) in case it exists in the waiting cache
+ // This lookup can fail because the contents of
+ // `self.waiting_cache` is not guaranteed to match those of
+ // `self.nodes`. See the comment in `process_obligation`
+ // for more details.
if let Some((predicate, _)) = self.waiting_cache
- .remove_entry(self.nodes[i].obligation.as_predicate())
+ .remove_entry(node.obligation.as_predicate())
{
self.done_cache.insert(predicate);
} else {
- self.done_cache.insert(self.nodes[i].obligation.as_predicate().clone());
+ self.done_cache.insert(node.obligation.as_predicate().clone());
}
node_rewrites[i] = nodes_len;
dead_nodes += 1;
@@ -643,7 +662,7 @@
// We *intentionally* remove the node from the cache at this point. Otherwise
// tests must come up with a different type on every type error they
// check against.
- self.waiting_cache.remove(self.nodes[i].obligation.as_predicate());
+ self.waiting_cache.remove(node.obligation.as_predicate());
node_rewrites[i] = nodes_len;
dead_nodes += 1;
self.insert_into_error_cache(i);
@@ -655,12 +674,11 @@
// No compression needed.
if dead_nodes == 0 {
node_rewrites.truncate(0);
- self.scratch = Some(node_rewrites);
+ self.scratch.replace(node_rewrites);
return if do_completed == DoCompleted::Yes { Some(vec![]) } else { None };
}
- // Pop off all the nodes we killed and extract the success
- // stories.
+ // Pop off all the nodes we killed and extract the success stories.
let successful = if do_completed == DoCompleted::Yes {
Some((0..dead_nodes)
.map(|_| self.nodes.pop().unwrap())
@@ -679,7 +697,7 @@
self.apply_rewrites(&node_rewrites);
node_rewrites.truncate(0);
- self.scratch = Some(node_rewrites);
+ self.scratch.replace(node_rewrites);
successful
}
@@ -689,58 +707,41 @@
for node in &mut self.nodes {
if let Some(index) = node.parent {
- let new_index = node_rewrites[index.get()];
- if new_index >= nodes_len {
- // parent dead due to error
+ let new_i = node_rewrites[index.index()];
+ if new_i >= nodes_len {
node.parent = None;
} else {
- node.parent = Some(NodeIndex::new(new_index));
+ node.parent = Some(NodeIndex::new(new_i));
}
}
let mut i = 0;
while i < node.dependents.len() {
- let new_index = node_rewrites[node.dependents[i].get()];
- if new_index >= nodes_len {
+ let new_i = node_rewrites[node.dependents[i].index()];
+ if new_i >= nodes_len {
node.dependents.swap_remove(i);
} else {
- node.dependents[i] = NodeIndex::new(new_index);
+ node.dependents[i] = NodeIndex::new(new_i);
i += 1;
}
}
}
- let mut kill_list = vec![];
- for (predicate, index) in &mut self.waiting_cache {
- let new_index = node_rewrites[index.get()];
- if new_index >= nodes_len {
- kill_list.push(predicate.clone());
+ // This updating of `self.waiting_cache` is necessary because the
+ // removal of nodes within `compress` can fail. See above.
+ self.waiting_cache.retain(|_predicate, index| {
+ let new_i = node_rewrites[index.index()];
+ if new_i >= nodes_len {
+ false
} else {
- *index = NodeIndex::new(new_index);
+ *index = NodeIndex::new(new_i);
+ true
}
- }
-
- for predicate in kill_list { self.waiting_cache.remove(&predicate); }
+ });
}
}
-impl<O> Node<O> {
- fn new(
- parent: Option<NodeIndex>,
- obligation: O,
- obligation_tree_id: ObligationTreeId
- ) -> Node<O> {
- Node {
- obligation,
- state: Cell::new(NodeState::Pending),
- parent,
- dependents: vec![],
- obligation_tree_id,
- }
- }
-}
-
-// I need a Clone closure
+// I need a Clone closure.
#[derive(Clone)]
struct GetObligation<'a, O>(&'a [Node<O>]);
diff --git a/src/librustc_data_structures/obligation_forest/node_index.rs b/src/librustc_data_structures/obligation_forest/node_index.rs
deleted file mode 100644
index 69ea473..0000000
--- a/src/librustc_data_structures/obligation_forest/node_index.rs
+++ /dev/null
@@ -1,20 +0,0 @@
-use std::num::NonZeroU32;
-use std::u32;
-
-#[derive(Copy, Clone, Debug, PartialEq, Eq)]
-pub struct NodeIndex {
- index: NonZeroU32,
-}
-
-impl NodeIndex {
- #[inline]
- pub fn new(value: usize) -> NodeIndex {
- assert!(value < (u32::MAX as usize));
- NodeIndex { index: NonZeroU32::new((value as u32) + 1).unwrap() }
- }
-
- #[inline]
- pub fn get(self) -> usize {
- (self.index.get() - 1) as usize
- }
-}
diff --git a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs
index efa1858..26a89b4 100644
--- a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs
@@ -13,7 +13,7 @@
use rustc::mir::{ConstraintCategory, Location, Body};
use rustc::ty::{self, RegionVid};
use rustc_data_structures::indexed_vec::IndexVec;
-use rustc_errors::{Diagnostic, DiagnosticBuilder};
+use rustc_errors::DiagnosticBuilder;
use std::collections::VecDeque;
use syntax::errors::Applicability;
use syntax::symbol::kw;
@@ -22,7 +22,7 @@
mod region_name;
mod var_name;
-crate use self::region_name::{RegionName, RegionNameSource};
+crate use self::region_name::{RegionName, RegionNameSource, RegionErrorNamingCtx};
impl ConstraintDescription for ConstraintCategory {
fn description(&self) -> &'static str {
@@ -54,6 +54,39 @@
NotVisited,
}
+/// Various pieces of state used when reporting borrow checker errors.
+pub struct ErrorReportingCtx<'a, 'b, 'tcx> {
+ /// The region inference context used for borrow chekcing this MIR body.
+ #[allow(dead_code)] // FIXME(mark-i-m): used by outlives suggestions
+ region_infcx: &'b RegionInferenceContext<'tcx>,
+
+ /// The inference context used for type checking.
+ infcx: &'b InferCtxt<'a, 'tcx>,
+
+ /// The MIR def we are reporting errors on.
+ mir_def_id: DefId,
+
+ /// The MIR body we are reporting errors on (for convenience).
+ body: &'b Body<'tcx>,
+
+ /// Any upvars for the MIR body we have kept track of during borrow checking.
+ upvars: &'b [Upvar],
+}
+
+/// Information about the various region constraints involved in a borrow checker error.
+#[derive(Clone, Debug)]
+pub struct ErrorConstraintInfo {
+ // fr: outlived_fr
+ fr: RegionVid,
+ fr_is_local: bool,
+ outlived_fr: RegionVid,
+ outlived_fr_is_local: bool,
+
+ // Category and span for best blame constraint
+ category: ConstraintCategory,
+ span: Span,
+}
+
impl<'tcx> RegionInferenceContext<'tcx> {
/// Tries to find the best constraint to blame for the fact that
/// `R: from_region`, where `R` is some region that meets
@@ -257,16 +290,16 @@
/// ```
///
/// Here we would be invoked with `fr = 'a` and `outlived_fr = `'b`.
- pub(super) fn report_error(
- &self,
+ pub(super) fn report_error<'a>(
+ &'a self,
body: &Body<'tcx>,
upvars: &[Upvar],
- infcx: &InferCtxt<'_, 'tcx>,
+ infcx: &'a InferCtxt<'a, 'tcx>,
mir_def_id: DefId,
fr: RegionVid,
outlived_fr: RegionVid,
- errors_buffer: &mut Vec<Diagnostic>,
- ) {
+ renctx: &mut RegionErrorNamingCtx,
+ ) -> DiagnosticBuilder<'a> {
debug!("report_error(fr={:?}, outlived_fr={:?})", fr, outlived_fr);
let (category, _, span) = self.best_blame_constraint(body, fr, |r| {
@@ -279,8 +312,7 @@
let tables = infcx.tcx.typeck_tables_of(mir_def_id);
let nice = NiceRegionError::new_from_span(infcx, span, o, f, Some(tables));
if let Some(diag) = nice.try_report_from_nll() {
- diag.buffer(errors_buffer);
- return;
+ return diag;
}
}
@@ -293,45 +325,28 @@
"report_error: fr_is_local={:?} outlived_fr_is_local={:?} category={:?}",
fr_is_local, outlived_fr_is_local, category
);
+
+ let errctx = ErrorReportingCtx {
+ region_infcx: self,
+ infcx,
+ mir_def_id,
+ body,
+ upvars,
+ };
+
+ let errci = ErrorConstraintInfo {
+ fr, outlived_fr, fr_is_local, outlived_fr_is_local, category, span
+ };
+
match (category, fr_is_local, outlived_fr_is_local) {
(ConstraintCategory::Return, true, false) if self.is_closure_fn_mut(infcx, fr) => {
- self.report_fnmut_error(
- body,
- upvars,
- infcx,
- mir_def_id,
- fr,
- outlived_fr,
- span,
- errors_buffer,
- )
+ self.report_fnmut_error(&errctx, &errci, renctx)
}
(ConstraintCategory::Assignment, true, false)
- | (ConstraintCategory::CallArgument, true, false) => self.report_escaping_data_error(
- body,
- upvars,
- infcx,
- mir_def_id,
- fr,
- outlived_fr,
- category,
- span,
- errors_buffer,
- ),
- _ => self.report_general_error(
- body,
- upvars,
- infcx,
- mir_def_id,
- fr,
- fr_is_local,
- outlived_fr,
- outlived_fr_is_local,
- category,
- span,
- errors_buffer,
- ),
- };
+ | (ConstraintCategory::CallArgument, true, false) =>
+ self.report_escaping_data_error(&errctx, &errci, renctx),
+ _ => self.report_general_error(&errctx, &errci, renctx),
+ }
}
/// We have a constraint `fr1: fr2` that is not satisfied, where
@@ -379,19 +394,19 @@
/// ```
fn report_fnmut_error(
&self,
- body: &Body<'tcx>,
- upvars: &[Upvar],
- infcx: &InferCtxt<'_, 'tcx>,
- mir_def_id: DefId,
- _fr: RegionVid,
- outlived_fr: RegionVid,
- span: Span,
- errors_buffer: &mut Vec<Diagnostic>,
- ) {
- let mut diag = infcx
+ errctx: &ErrorReportingCtx<'_, '_, 'tcx>,
+ errci: &ErrorConstraintInfo,
+ renctx: &mut RegionErrorNamingCtx,
+ ) -> DiagnosticBuilder<'_> {
+ let ErrorConstraintInfo {
+ outlived_fr, span, ..
+ } = errci;
+
+ let mut diag = errctx
+ .infcx
.tcx
.sess
- .struct_span_err(span, "captured variable cannot escape `FnMut` closure body");
+ .struct_span_err(*span, "captured variable cannot escape `FnMut` closure body");
// We should check if the return type of this closure is in fact a closure - in that
// case, we can special case the error further.
@@ -403,11 +418,9 @@
"returns a reference to a captured variable which escapes the closure body"
};
- diag.span_label(span, message);
+ diag.span_label(*span, message);
- match self.give_region_a_name(infcx, body, upvars, mir_def_id, outlived_fr, &mut 1)
- .unwrap().source
- {
+ match self.give_region_a_name(errctx, renctx, *outlived_fr).unwrap().source {
RegionNameSource::NamedEarlyBoundRegion(fr_span)
| RegionNameSource::NamedFreeRegion(fr_span)
| RegionNameSource::SynthesizedFreeEnvRegion(fr_span, _)
@@ -427,7 +440,7 @@
);
diag.note("...therefore, they cannot allow references to captured variables to escape");
- diag.buffer(errors_buffer);
+ diag
}
/// Reports a error specifically for when data is escaping a closure.
@@ -444,20 +457,22 @@
/// ```
fn report_escaping_data_error(
&self,
- body: &Body<'tcx>,
- upvars: &[Upvar],
- infcx: &InferCtxt<'_, 'tcx>,
- mir_def_id: DefId,
- fr: RegionVid,
- outlived_fr: RegionVid,
- category: ConstraintCategory,
- span: Span,
- errors_buffer: &mut Vec<Diagnostic>,
- ) {
+ errctx: &ErrorReportingCtx<'_, '_, 'tcx>,
+ errci: &ErrorConstraintInfo,
+ renctx: &mut RegionErrorNamingCtx,
+ ) -> DiagnosticBuilder<'_> {
+ let ErrorReportingCtx {
+ infcx, body, upvars, ..
+ } = errctx;
+
+ let ErrorConstraintInfo {
+ span, category, ..
+ } = errci;
+
let fr_name_and_span =
- self.get_var_name_and_span_for_region(infcx.tcx, body, upvars, fr);
+ self.get_var_name_and_span_for_region(infcx.tcx, body, upvars, errci.fr);
let outlived_fr_name_and_span =
- self.get_var_name_and_span_for_region(infcx.tcx, body, upvars, outlived_fr);
+ self.get_var_name_and_span_for_region(infcx.tcx, body, upvars, errci.outlived_fr);
let escapes_from = match self.universal_regions.defining_ty {
DefiningTy::Closure(..) => "closure",
@@ -469,27 +484,23 @@
// Revert to the normal error in these cases.
// Assignments aren't "escapes" in function items.
if (fr_name_and_span.is_none() && outlived_fr_name_and_span.is_none())
- || (category == ConstraintCategory::Assignment && escapes_from == "function")
+ || (*category == ConstraintCategory::Assignment && escapes_from == "function")
|| escapes_from == "const"
{
return self.report_general_error(
- body,
- upvars,
- infcx,
- mir_def_id,
- fr,
- true,
- outlived_fr,
- false,
- category,
- span,
- errors_buffer,
+ errctx,
+ &ErrorConstraintInfo {
+ fr_is_local: true,
+ outlived_fr_is_local: false,
+ .. *errci
+ },
+ renctx,
);
}
let mut diag = borrowck_errors::borrowed_data_escapes_closure(
infcx.tcx,
- span,
+ *span,
escapes_from,
);
@@ -513,12 +524,12 @@
);
diag.span_label(
- span,
+ *span,
format!("`{}` escapes the {} body here", fr_name, escapes_from),
);
}
- diag.buffer(errors_buffer);
+ diag
}
/// Reports a region inference error for the general case with named/synthesized lifetimes to
@@ -538,41 +549,37 @@
/// ```
fn report_general_error(
&self,
- body: &Body<'tcx>,
- upvars: &[Upvar],
- infcx: &InferCtxt<'_, 'tcx>,
- mir_def_id: DefId,
- fr: RegionVid,
- fr_is_local: bool,
- outlived_fr: RegionVid,
- outlived_fr_is_local: bool,
- category: ConstraintCategory,
- span: Span,
- errors_buffer: &mut Vec<Diagnostic>,
- ) {
+ errctx: &ErrorReportingCtx<'_, '_, 'tcx>,
+ errci: &ErrorConstraintInfo,
+ renctx: &mut RegionErrorNamingCtx,
+ ) -> DiagnosticBuilder<'_> {
+ let ErrorReportingCtx {
+ infcx, mir_def_id, ..
+ } = errctx;
+ let ErrorConstraintInfo {
+ fr, fr_is_local, outlived_fr, outlived_fr_is_local, span, category, ..
+ } = errci;
+
let mut diag = infcx.tcx.sess.struct_span_err(
- span,
+ *span,
"lifetime may not live long enough"
);
- let counter = &mut 1;
- let fr_name = self.give_region_a_name(
- infcx, body, upvars, mir_def_id, fr, counter).unwrap();
- fr_name.highlight_region_name(&mut diag);
- let outlived_fr_name =
- self.give_region_a_name(infcx, body, upvars, mir_def_id, outlived_fr, counter).unwrap();
- outlived_fr_name.highlight_region_name(&mut diag);
-
- let mir_def_name = if infcx.tcx.is_closure(mir_def_id) {
+ let mir_def_name = if infcx.tcx.is_closure(*mir_def_id) {
"closure"
} else {
"function"
};
+ let fr_name = self.give_region_a_name(errctx, renctx, *fr).unwrap();
+ fr_name.highlight_region_name(&mut diag);
+ let outlived_fr_name = self.give_region_a_name(errctx, renctx, *outlived_fr).unwrap();
+ outlived_fr_name.highlight_region_name(&mut diag);
+
match (category, outlived_fr_is_local, fr_is_local) {
(ConstraintCategory::Return, true, _) => {
diag.span_label(
- span,
+ *span,
format!(
"{} was supposed to return data with lifetime `{}` but it is returning \
data with lifetime `{}`",
@@ -582,7 +589,7 @@
}
_ => {
diag.span_label(
- span,
+ *span,
format!(
"{}requires that `{}` must outlive `{}`",
category.description(),
@@ -593,9 +600,9 @@
}
}
- self.add_static_impl_trait_suggestion(infcx, &mut diag, fr, fr_name, outlived_fr);
+ self.add_static_impl_trait_suggestion(infcx, &mut diag, *fr, fr_name, *outlived_fr);
- diag.buffer(errors_buffer);
+ diag
}
/// Adds a suggestion to errors where a `impl Trait` is returned.
@@ -704,8 +711,14 @@
borrow_region,
|r| self.provides_universal_region(r, borrow_region, outlived_region)
);
- let outlived_fr_name =
- self.give_region_a_name(infcx, body, upvars, mir_def_id, outlived_region, &mut 1);
+
+ let mut renctx = RegionErrorNamingCtx::new();
+ let errctx = ErrorReportingCtx {
+ infcx, body, upvars, mir_def_id,
+ region_infcx: self,
+ };
+ let outlived_fr_name = self.give_region_a_name(&errctx, &mut renctx, outlived_region);
+
(category, from_closure, span, outlived_fr_name)
}
diff --git a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs
index 75a3162..6fa9426 100644
--- a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs
+++ b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs
@@ -1,5 +1,9 @@
use std::fmt::{self, Display};
-use crate::borrow_check::nll::region_infer::RegionInferenceContext;
+
+use crate::borrow_check::nll::region_infer::{
+ RegionInferenceContext,
+ error_reporting::ErrorReportingCtx,
+};
use crate::borrow_check::nll::universal_regions::DefiningTy;
use crate::borrow_check::nll::ToRegionVid;
use crate::borrow_check::Upvar;
@@ -13,29 +17,75 @@
use rustc::ty::print::RegionHighlightMode;
use rustc_errors::DiagnosticBuilder;
use syntax::symbol::kw;
-use syntax_pos::Span;
-use syntax_pos::symbol::InternedString;
+use rustc_data_structures::fx::FxHashMap;
+use syntax_pos::{Span, symbol::InternedString};
-#[derive(Debug)]
+/// A name for a particular region used in emitting diagnostics. This name could be a generated
+/// name like `'1`, a name used by the user like `'a`, or a name like `'static`.
+#[derive(Debug, Clone)]
crate struct RegionName {
+ /// The name of the region (interned).
crate name: InternedString,
+ /// Where the region comes from.
crate source: RegionNameSource,
}
-#[derive(Debug)]
+/// Denotes the source of a region that is named by a `RegionName`. For example, a free region that
+/// was named by the user would get `NamedFreeRegion` and `'static` lifetime would get `Static`.
+/// This helps to print the right kinds of diagnostics.
+#[derive(Debug, Clone)]
crate enum RegionNameSource {
+ /// A bound (not free) region that was substituted at the def site (not an HRTB).
NamedEarlyBoundRegion(Span),
+ /// A free region that the user has a name (`'a`) for.
NamedFreeRegion(Span),
+ /// The `'static` region.
Static,
+ /// The free region corresponding to the environment of a closure.
SynthesizedFreeEnvRegion(Span, String),
+ /// The region name corresponds to a region where the type annotation is completely missing
+ /// from the code, e.g. in a closure arguments `|x| { ... }`, where `x` is a reference.
CannotMatchHirTy(Span, String),
+ /// The region name corresponds a reference that was found by traversing the type in the HIR.
MatchedHirTy(Span),
+ /// A region name from the generics list of a struct/enum/union.
MatchedAdtAndSegment(Span),
+ /// The region corresponding to a closure upvar.
AnonRegionFromUpvar(Span, String),
+ /// The region corresponding to the return type of a closure.
AnonRegionFromOutput(Span, String, String),
AnonRegionFromYieldTy(Span, String),
}
+/// Records region names that have been assigned before so that we can use the same ones in later
+/// diagnostics.
+#[derive(Debug, Clone)]
+crate struct RegionErrorNamingCtx {
+ /// Record the region names generated for each region in the given
+ /// MIR def so that we can reuse them later in help/error messages.
+ renctx: FxHashMap<RegionVid, RegionName>,
+
+ /// The counter for generating new region names.
+ counter: usize,
+}
+
+impl RegionErrorNamingCtx {
+ crate fn new() -> Self {
+ Self {
+ counter: 1,
+ renctx: FxHashMap::default(),
+ }
+ }
+
+ crate fn get(&self, region: &RegionVid) -> Option<&RegionName> {
+ self.renctx.get(region)
+ }
+
+ crate fn insert(&mut self, region: RegionVid, name: RegionName) {
+ self.renctx.insert(region, name);
+ }
+}
+
impl RegionName {
#[allow(dead_code)]
crate fn was_named(&self) -> bool {
@@ -63,43 +113,40 @@
self.name
}
- crate fn highlight_region_name(
- &self,
- diag: &mut DiagnosticBuilder<'_>
- ) {
+ crate fn highlight_region_name(&self, diag: &mut DiagnosticBuilder<'_>) {
match &self.source {
- RegionNameSource::NamedFreeRegion(span) |
- RegionNameSource::NamedEarlyBoundRegion(span) => {
- diag.span_label(
- *span,
- format!("lifetime `{}` defined here", self),
- );
- },
+ RegionNameSource::NamedFreeRegion(span)
+ | RegionNameSource::NamedEarlyBoundRegion(span) => {
+ diag.span_label(*span, format!("lifetime `{}` defined here", self));
+ }
RegionNameSource::SynthesizedFreeEnvRegion(span, note) => {
diag.span_label(
*span,
format!("lifetime `{}` represents this closure's body", self),
);
diag.note(¬e);
- },
+ }
RegionNameSource::CannotMatchHirTy(span, type_name) => {
diag.span_label(*span, format!("has type `{}`", type_name));
- },
+ }
RegionNameSource::MatchedHirTy(span) => {
diag.span_label(
*span,
format!("let's call the lifetime of this reference `{}`", self),
);
- },
+ }
RegionNameSource::MatchedAdtAndSegment(span) => {
diag.span_label(*span, format!("let's call this `{}`", self));
- },
+ }
RegionNameSource::AnonRegionFromUpvar(span, upvar_name) => {
diag.span_label(
*span,
- format!("lifetime `{}` appears in the type of `{}`", self, upvar_name),
+ format!(
+ "lifetime `{}` appears in the type of `{}`",
+ self, upvar_name
+ ),
);
- },
+ }
RegionNameSource::AnonRegionFromOutput(span, mir_description, type_name) => {
diag.span_label(
*span,
@@ -151,39 +198,49 @@
/// and then return the name `'1` for us to use.
crate fn give_region_a_name(
&self,
- infcx: &InferCtxt<'_, 'tcx>,
- body: &Body<'tcx>,
- upvars: &[Upvar],
- mir_def_id: DefId,
+ errctx: &ErrorReportingCtx<'_, '_, 'tcx>,
+ renctx: &mut RegionErrorNamingCtx,
fr: RegionVid,
- counter: &mut usize,
) -> Option<RegionName> {
- debug!("give_region_a_name(fr={:?}, counter={})", fr, counter);
+ let ErrorReportingCtx {
+ infcx, body, mir_def_id, upvars, ..
+ } = errctx;
+
+ debug!("give_region_a_name(fr={:?}, counter={:?})", fr, renctx.counter);
assert!(self.universal_regions.is_universal_region(fr));
- let value = self.give_name_from_error_region(infcx.tcx, mir_def_id, fr, counter)
+ if let Some(value) = renctx.get(&fr) {
+ return Some(value.clone());
+ }
+
+ let value = self
+ .give_name_from_error_region(infcx.tcx, *mir_def_id, fr, renctx)
.or_else(|| {
self.give_name_if_anonymous_region_appears_in_arguments(
- infcx, body, mir_def_id, fr, counter,
+ infcx, body, *mir_def_id, fr, renctx,
)
})
.or_else(|| {
self.give_name_if_anonymous_region_appears_in_upvars(
- infcx.tcx, upvars, fr, counter,
+ infcx.tcx, upvars, fr, renctx
)
})
.or_else(|| {
self.give_name_if_anonymous_region_appears_in_output(
- infcx, body, mir_def_id, fr, counter,
+ infcx, body, *mir_def_id, fr, renctx,
)
})
.or_else(|| {
self.give_name_if_anonymous_region_appears_in_yield_ty(
- infcx, body, mir_def_id, fr, counter,
+ infcx, body, *mir_def_id, fr, renctx,
)
});
+ if let Some(ref value) = value {
+ renctx.insert(fr, value.clone());
+ }
+
debug!("give_region_a_name: gave name {:?}", value);
value
}
@@ -197,7 +254,7 @@
tcx: TyCtxt<'tcx>,
mir_def_id: DefId,
fr: RegionVid,
- counter: &mut usize,
+ renctx: &mut RegionErrorNamingCtx,
) -> Option<RegionName> {
let error_region = self.to_error_region(fr)?;
@@ -208,7 +265,7 @@
let span = self.get_named_span(tcx, error_region, ebr.name);
Some(RegionName {
name: ebr.name,
- source: RegionNameSource::NamedEarlyBoundRegion(span)
+ source: RegionNameSource::NamedEarlyBoundRegion(span),
})
} else {
None
@@ -227,12 +284,10 @@
name,
source: RegionNameSource::NamedFreeRegion(span),
})
- },
+ }
ty::BoundRegion::BrEnv => {
- let mir_hir_id = tcx.hir()
- .as_local_hir_id(mir_def_id)
- .expect("non-local mir");
+ let mir_hir_id = tcx.hir().as_local_hir_id(mir_def_id).expect("non-local mir");
let def_ty = self.universal_regions.defining_ty;
if let DefiningTy::Closure(def_id, substs) = def_ty {
@@ -243,7 +298,7 @@
} else {
bug!("Closure is not defined by a closure expr");
};
- let region_name = self.synthesize_region_name(counter);
+ let region_name = self.synthesize_region_name(renctx);
let closure_kind_ty = substs.closure_kind_ty(def_id, tcx);
let note = match closure_kind_ty.to_opt_closure_kind() {
@@ -265,7 +320,7 @@
name: region_name,
source: RegionNameSource::SynthesizedFreeEnvRegion(
args_span,
- note.to_string()
+ note.to_string(),
),
})
} else {
@@ -335,7 +390,7 @@
body: &Body<'tcx>,
mir_def_id: DefId,
fr: RegionVid,
- counter: &mut usize,
+ renctx: &mut RegionErrorNamingCtx,
) -> Option<RegionName> {
let implicit_inputs = self.universal_regions.defining_ty.implicit_inputs();
let argument_index = self.get_argument_index_for_region(infcx.tcx, fr)?;
@@ -349,12 +404,12 @@
fr,
arg_ty,
argument_index,
- counter,
+ renctx,
) {
return Some(region_name);
}
- self.give_name_if_we_cannot_match_hir_ty(infcx, body, fr, arg_ty, counter)
+ self.give_name_if_we_cannot_match_hir_ty(infcx, body, fr, arg_ty, renctx)
}
fn give_name_if_we_can_match_hir_ty_from_argument(
@@ -365,7 +420,7 @@
needle_fr: RegionVid,
argument_ty: Ty<'tcx>,
argument_index: usize,
- counter: &mut usize,
+ renctx: &mut RegionErrorNamingCtx,
) -> Option<RegionName> {
let mir_hir_id = infcx.tcx.hir().as_local_hir_id(mir_def_id)?;
let fn_decl = infcx.tcx.hir().fn_decl_by_hir_id(mir_hir_id)?;
@@ -379,7 +434,7 @@
body,
needle_fr,
argument_ty,
- counter,
+ renctx,
),
_ => self.give_name_if_we_can_match_hir_ty(
@@ -387,7 +442,7 @@
needle_fr,
argument_ty,
argument_hir_ty,
- counter,
+ renctx,
),
}
}
@@ -409,10 +464,11 @@
body: &Body<'tcx>,
needle_fr: RegionVid,
argument_ty: Ty<'tcx>,
- counter: &mut usize,
+ renctx: &mut RegionErrorNamingCtx,
) -> Option<RegionName> {
+ let counter = renctx.counter;
let mut highlight = RegionHighlightMode::default();
- highlight.highlighting_region_vid(needle_fr, *counter);
+ highlight.highlighting_region_vid(needle_fr, counter);
let type_name = infcx.extract_type_name(&argument_ty, Some(highlight)).0;
debug!(
@@ -428,7 +484,7 @@
// This counter value will already have been used, so this function will increment
// it so the next value will be used next and return the region name that would
// have been used.
- name: self.synthesize_region_name(counter),
+ name: self.synthesize_region_name(renctx),
source: RegionNameSource::CannotMatchHirTy(span, type_name),
})
} else {
@@ -455,7 +511,7 @@
/// type. Once we find that, we can use the span of the `hir::Ty`
/// to add the highlight.
///
- /// This is a somewhat imperfect process, so long the way we also
+ /// This is a somewhat imperfect process, so along the way we also
/// keep track of the **closest** type we've found. If we fail to
/// find the exact `&` or `'_` to highlight, then we may fall back
/// to highlighting that closest type instead.
@@ -465,7 +521,7 @@
needle_fr: RegionVid,
argument_ty: Ty<'tcx>,
argument_hir_ty: &hir::Ty,
- counter: &mut usize,
+ renctx: &mut RegionErrorNamingCtx,
) -> Option<RegionName> {
let search_stack: &mut Vec<(Ty<'tcx>, &hir::Ty)> =
&mut vec![(argument_ty, argument_hir_ty)];
@@ -483,7 +539,7 @@
hir::TyKind::Rptr(_lifetime, referent_hir_ty),
) => {
if region.to_region_vid() == needle_fr {
- let region_name = self.synthesize_region_name(counter);
+ let region_name = self.synthesize_region_name(renctx);
// Just grab the first character, the `&`.
let source_map = tcx.sess.source_map();
@@ -515,7 +571,7 @@
substs,
needle_fr,
last_segment,
- counter,
+ renctx,
search_stack,
) {
return Some(name);
@@ -559,18 +615,19 @@
substs: SubstsRef<'tcx>,
needle_fr: RegionVid,
last_segment: &'hir hir::PathSegment,
- counter: &mut usize,
+ renctx: &mut RegionErrorNamingCtx,
search_stack: &mut Vec<(Ty<'tcx>, &'hir hir::Ty)>,
) -> Option<RegionName> {
// Did the user give explicit arguments? (e.g., `Foo<..>`)
let args = last_segment.args.as_ref()?;
- let lifetime = self.try_match_adt_and_generic_args(substs, needle_fr, args, search_stack)?;
+ let lifetime =
+ self.try_match_adt_and_generic_args(substs, needle_fr, args, search_stack)?;
match lifetime.name {
hir::LifetimeName::Param(_)
| hir::LifetimeName::Error
| hir::LifetimeName::Static
| hir::LifetimeName::Underscore => {
- let region_name = self.synthesize_region_name(counter);
+ let region_name = self.synthesize_region_name(renctx);
let ampersand_span = lifetime.span;
Some(RegionName {
name: region_name,
@@ -657,12 +714,12 @@
tcx: TyCtxt<'tcx>,
upvars: &[Upvar],
fr: RegionVid,
- counter: &mut usize,
+ renctx: &mut RegionErrorNamingCtx,
) -> Option<RegionName> {
let upvar_index = self.get_upvar_index_for_region(tcx, fr)?;
let (upvar_name, upvar_span) =
self.get_upvar_name_and_span_for_region(tcx, upvars, upvar_index);
- let region_name = self.synthesize_region_name(counter);
+ let region_name = self.synthesize_region_name(renctx);
Some(RegionName {
name: region_name,
@@ -680,7 +737,7 @@
body: &Body<'tcx>,
mir_def_id: DefId,
fr: RegionVid,
- counter: &mut usize,
+ renctx: &mut RegionErrorNamingCtx,
) -> Option<RegionName> {
let tcx = infcx.tcx;
@@ -694,7 +751,7 @@
}
let mut highlight = RegionHighlightMode::default();
- highlight.highlighting_region_vid(fr, *counter);
+ highlight.highlighting_region_vid(fr, renctx.counter);
let type_name = infcx.extract_type_name(&return_ty, Some(highlight)).0;
let mir_hir_id = tcx.hir().as_local_hir_id(mir_def_id).expect("non-local mir");
@@ -725,11 +782,11 @@
// This counter value will already have been used, so this function will increment it
// so the next value will be used next and return the region name that would have been
// used.
- name: self.synthesize_region_name(counter),
+ name: self.synthesize_region_name(renctx),
source: RegionNameSource::AnonRegionFromOutput(
return_span,
mir_description.to_string(),
- type_name
+ type_name,
),
})
}
@@ -740,7 +797,7 @@
body: &Body<'tcx>,
mir_def_id: DefId,
fr: RegionVid,
- counter: &mut usize,
+ renctx: &mut RegionErrorNamingCtx,
) -> Option<RegionName> {
// Note: generators from `async fn` yield `()`, so we don't have to
// worry about them here.
@@ -757,7 +814,7 @@
}
let mut highlight = RegionHighlightMode::default();
- highlight.highlighting_region_vid(fr, *counter);
+ highlight.highlighting_region_vid(fr, renctx.counter);
let type_name = infcx.extract_type_name(&yield_ty, Some(highlight)).0;
let mir_hir_id = tcx.hir().as_local_hir_id(mir_def_id).expect("non-local mir");
@@ -780,16 +837,15 @@
);
Some(RegionName {
- name: self.synthesize_region_name(counter),
+ name: self.synthesize_region_name(renctx),
source: RegionNameSource::AnonRegionFromYieldTy(yield_span, type_name),
})
}
- /// Creates a synthetic region named `'1`, incrementing the
- /// counter.
- fn synthesize_region_name(&self, counter: &mut usize) -> InternedString {
- let c = *counter;
- *counter += 1;
+ /// Creates a synthetic region named `'1`, incrementing the counter.
+ fn synthesize_region_name(&self, renctx: &mut RegionErrorNamingCtx) -> InternedString {
+ let c = renctx.counter;
+ renctx.counter += 1;
InternedString::intern(&format!("'{:?}", c))
}
diff --git a/src/librustc_mir/borrow_check/nll/region_infer/mod.rs b/src/librustc_mir/borrow_check/nll/region_infer/mod.rs
index 4038872..78e7943 100644
--- a/src/librustc_mir/borrow_check/nll/region_infer/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/region_infer/mod.rs
@@ -1,15 +1,20 @@
-use super::universal_regions::UniversalRegions;
-use crate::borrow_check::nll::constraints::graph::NormalConstraintGraph;
-use crate::borrow_check::nll::constraints::{
- ConstraintSccIndex, OutlivesConstraint, OutlivesConstraintSet,
+use std::rc::Rc;
+
+use crate::borrow_check::nll::{
+ constraints::{
+ graph::NormalConstraintGraph,
+ ConstraintSccIndex,
+ OutlivesConstraint,
+ OutlivesConstraintSet,
+ },
+ member_constraints::{MemberConstraintSet, NllMemberConstraintIndex},
+ region_infer::values::{
+ PlaceholderIndices, RegionElement, ToElementIndex
+ },
+ type_check::{free_region_relations::UniversalRegionRelations, Locations},
};
-use crate::borrow_check::nll::member_constraints::{MemberConstraintSet, NllMemberConstraintIndex};
-use crate::borrow_check::nll::region_infer::values::{
- PlaceholderIndices, RegionElement, ToElementIndex,
-};
-use crate::borrow_check::nll::type_check::free_region_relations::UniversalRegionRelations;
-use crate::borrow_check::nll::type_check::Locations;
use crate::borrow_check::Upvar;
+
use rustc::hir::def_id::DefId;
use rustc::infer::canonical::QueryOutlivesConstraint;
use rustc::infer::opaque_types;
@@ -31,16 +36,16 @@
use rustc_errors::{Diagnostic, DiagnosticBuilder};
use syntax_pos::Span;
-use std::rc::Rc;
+crate use self::error_reporting::{RegionName, RegionNameSource, RegionErrorNamingCtx};
+use self::values::{LivenessValues, RegionValueElements, RegionValues};
+use super::universal_regions::UniversalRegions;
+use super::ToRegionVid;
mod dump_mir;
mod error_reporting;
-crate use self::error_reporting::{RegionName, RegionNameSource};
mod graphviz;
-pub mod values;
-use self::values::{LivenessValues, RegionValueElements, RegionValues};
-use super::ToRegionVid;
+pub mod values;
pub struct RegionInferenceContext<'tcx> {
/// Contains the definition for every region variable. Region
@@ -487,6 +492,12 @@
errors_buffer,
);
+ // If we produce any errors, we keep track of the names of all regions, so that we can use
+ // the same error names in any suggestions we produce. Note that we need names to be unique
+ // across different errors for the same MIR def so that we can make suggestions that fix
+ // multiple problems.
+ let mut region_naming = RegionErrorNamingCtx::new();
+
self.check_universal_regions(
infcx,
body,
@@ -494,6 +505,7 @@
mir_def_id,
outlives_requirements.as_mut(),
errors_buffer,
+ &mut region_naming,
);
self.check_member_constraints(infcx, mir_def_id, errors_buffer);
@@ -1312,6 +1324,7 @@
mir_def_id: DefId,
mut propagated_outlives_requirements: Option<&mut Vec<ClosureOutlivesRequirement<'tcx>>>,
errors_buffer: &mut Vec<Diagnostic>,
+ region_naming: &mut RegionErrorNamingCtx,
) {
for (fr, fr_definition) in self.definitions.iter_enumerated() {
match fr_definition.origin {
@@ -1327,6 +1340,7 @@
fr,
&mut propagated_outlives_requirements,
errors_buffer,
+ region_naming,
);
}
@@ -1358,6 +1372,7 @@
longer_fr: RegionVid,
propagated_outlives_requirements: &mut Option<&mut Vec<ClosureOutlivesRequirement<'tcx>>>,
errors_buffer: &mut Vec<Diagnostic>,
+ region_naming: &mut RegionErrorNamingCtx,
) {
debug!("check_universal_region(fr={:?})", longer_fr);
@@ -1385,6 +1400,7 @@
mir_def_id,
propagated_outlives_requirements,
errors_buffer,
+ region_naming,
);
return;
}
@@ -1401,8 +1417,13 @@
mir_def_id,
propagated_outlives_requirements,
errors_buffer,
+ region_naming,
) {
// continuing to iterate just reports more errors than necessary
+ //
+ // FIXME It would also allow us to report more Outlives Suggestions, though, so
+ // it's not clear that that's a bad thing. Somebody should try commenting out this
+ // line and see it is actually a regression.
return;
}
}
@@ -1418,6 +1439,7 @@
mir_def_id: DefId,
propagated_outlives_requirements: &mut Option<&mut Vec<ClosureOutlivesRequirement<'tcx>>>,
errors_buffer: &mut Vec<Diagnostic>,
+ region_naming: &mut RegionErrorNamingCtx,
) -> Option<ErrorReported> {
// If it is known that `fr: o`, carry on.
if self.universal_region_relations.outlives(longer_fr, shorter_fr) {
@@ -1466,7 +1488,18 @@
//
// Note: in this case, we use the unapproximated regions to report the
// error. This gives better error messages in some cases.
- self.report_error(body, upvars, infcx, mir_def_id, longer_fr, shorter_fr, errors_buffer);
+ let db = self.report_error(
+ body,
+ upvars,
+ infcx,
+ mir_def_id,
+ longer_fr,
+ shorter_fr,
+ region_naming,
+ );
+
+ db.buffer(errors_buffer);
+
Some(ErrorReported)
}
diff --git a/src/test/ui/c-variadic/variadic-ffi-4.nll.stderr b/src/test/ui/c-variadic/variadic-ffi-4.nll.stderr
index 4947d6e..ab8398e 100644
--- a/src/test/ui/c-variadic/variadic-ffi-4.nll.stderr
+++ b/src/test/ui/c-variadic/variadic-ffi-4.nll.stderr
@@ -37,11 +37,11 @@
--> $DIR/variadic-ffi-4.rs:20:5
|
LL | pub unsafe extern "C" fn no_escape3(_: usize, mut ap0: &mut VaListImpl, mut ap1: ...) {
- | ------- ------- has type `core::ffi::VaListImpl<'1>`
+ | ------- ------- has type `core::ffi::VaListImpl<'2>`
| |
- | has type `&mut core::ffi::VaListImpl<'2>`
+ | has type `&mut core::ffi::VaListImpl<'1>`
LL | *ap0 = ap1;
- | ^^^^ assignment requires that `'1` must outlive `'2`
+ | ^^^^ assignment requires that `'2` must outlive `'1`
error: lifetime may not live long enough
--> $DIR/variadic-ffi-4.rs:25:5
@@ -57,11 +57,11 @@
--> $DIR/variadic-ffi-4.rs:25:5
|
LL | pub unsafe extern "C" fn no_escape4(_: usize, ap0: &mut VaListImpl, mut ap1: ...) {
- | --- ------- has type `core::ffi::VaListImpl<'1>`
+ | --- ------- has type `core::ffi::VaListImpl<'2>`
| |
- | has type `&mut core::ffi::VaListImpl<'2>`
+ | has type `&mut core::ffi::VaListImpl<'1>`
LL | ap0 = &mut ap1;
- | ^^^^^^^^^^^^^^ assignment requires that `'1` must outlive `'2`
+ | ^^^^^^^^^^^^^^ assignment requires that `'2` must outlive `'1`
error[E0384]: cannot assign to immutable argument `ap0`
--> $DIR/variadic-ffi-4.rs:25:5
@@ -99,11 +99,11 @@
--> $DIR/variadic-ffi-4.rs:33:12
|
LL | pub unsafe extern "C" fn no_escape5(_: usize, mut ap0: &mut VaListImpl, mut ap1: ...) {
- | ------- ------- has type `core::ffi::VaListImpl<'1>`
+ | ------- ------- has type `core::ffi::VaListImpl<'2>`
| |
- | has type `&mut core::ffi::VaListImpl<'2>`
+ | has type `&mut core::ffi::VaListImpl<'1>`
LL | *ap0 = ap1.clone();
- | ^^^^^^^^^^^ argument requires that `'1` must outlive `'2`
+ | ^^^^^^^^^^^ argument requires that `'2` must outlive `'1`
error: aborting due to 11 previous errors
diff --git a/src/test/ui/generator/auto-trait-regions.stderr b/src/test/ui/generator/auto-trait-regions.stderr
index 92f92e2..dab4d34 100644
--- a/src/test/ui/generator/auto-trait-regions.stderr
+++ b/src/test/ui/generator/auto-trait-regions.stderr
@@ -1,20 +1,26 @@
error: implementation of `Foo` is not general enough
--> $DIR/auto-trait-regions.rs:30:5
|
+LL | auto trait Foo {}
+ | ----------------- trait `Foo` defined here
+...
LL | assert_foo(gen);
- | ^^^^^^^^^^
+ | ^^^^^^^^^^ implementation of `Foo` is not general enough
|
- = note: `Foo` would have to be implemented for the type `&'0 OnlyFooIfStaticRef`, for any lifetime `'0`
- = note: but `Foo` is actually implemented for the type `&'1 OnlyFooIfStaticRef`, for some specific lifetime `'1`
+ = note: `Foo` would have to be implemented for the type `&'0 OnlyFooIfStaticRef`, for any lifetime `'0`...
+ = note: ...but `Foo` is actually implemented for the type `&'1 OnlyFooIfStaticRef`, for some specific lifetime `'1`
error: implementation of `Foo` is not general enough
--> $DIR/auto-trait-regions.rs:48:5
|
+LL | auto trait Foo {}
+ | ----------------- trait `Foo` defined here
+...
LL | assert_foo(gen);
- | ^^^^^^^^^^
+ | ^^^^^^^^^^ implementation of `Foo` is not general enough
|
- = note: `Foo` would have to be implemented for the type `A<'0, '1>`, for any two lifetimes `'0` and `'1`
- = note: but `Foo` is actually implemented for the type `A<'_, '2>`, for some specific lifetime `'2`
+ = note: `Foo` would have to be implemented for the type `A<'0, '1>`, for any two lifetimes `'0` and `'1`...
+ = note: ...but `Foo` is actually implemented for the type `A<'_, '2>`, for some specific lifetime `'2`
error: aborting due to 2 previous errors
diff --git a/src/test/ui/hrtb/due-to-where-clause.rs b/src/test/ui/hrtb/due-to-where-clause.rs
new file mode 100644
index 0000000..04e2ddd
--- /dev/null
+++ b/src/test/ui/hrtb/due-to-where-clause.rs
@@ -0,0 +1,16 @@
+// ignore-compare-mode-nll
+// ^ This code works in nll mode.
+
+fn main() {
+ test::<FooS>(&mut 42); //~ ERROR implementation of `Foo` is not general enough
+}
+
+trait Foo<'a> {}
+
+struct FooS<'a> {
+ data: &'a mut u32,
+}
+
+impl<'a, 'b: 'a> Foo<'b> for FooS<'a> {}
+
+fn test<'a, F>(data: &'a mut u32) where F: for<'b> Foo<'b> {}
diff --git a/src/test/ui/hrtb/due-to-where-clause.stderr b/src/test/ui/hrtb/due-to-where-clause.stderr
new file mode 100644
index 0000000..e698584
--- /dev/null
+++ b/src/test/ui/hrtb/due-to-where-clause.stderr
@@ -0,0 +1,17 @@
+error: implementation of `Foo` is not general enough
+ --> $DIR/due-to-where-clause.rs:5:5
+ |
+LL | test::<FooS>(&mut 42);
+ | ^^^^^^^^^^^^ doesn't satisfy where-clause
+...
+LL | trait Foo<'a> {}
+ | ---------------- trait `Foo` defined here
+...
+LL | fn test<'a, F>(data: &'a mut u32) where F: for<'b> Foo<'b> {}
+ | ------------------------------------------------------------- due to a where-clause on `test`...
+ |
+ = note: ...`FooS<'_>` must implement `Foo<'0>`, for any lifetime `'0`...
+ = note: ...but `FooS<'_>` actually implements `Foo<'1>`, for some specific lifetime `'1`
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/hrtb/hrtb-cache-issue-54302.stderr b/src/test/ui/hrtb/hrtb-cache-issue-54302.stderr
index 77a5491..003f326 100644
--- a/src/test/ui/hrtb/hrtb-cache-issue-54302.stderr
+++ b/src/test/ui/hrtb/hrtb-cache-issue-54302.stderr
@@ -1,11 +1,14 @@
error: implementation of `Deserialize` is not general enough
--> $DIR/hrtb-cache-issue-54302.rs:19:5
|
+LL | trait Deserialize<'de> {}
+ | ------------------------- trait `Deserialize` defined here
+...
LL | assert_deserialize_owned::<&'static str>();
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ implementation of `Deserialize` is not general enough
|
- = note: `&'static str` must implement `Deserialize<'0>`, for any lifetime `'0`
- = note: but `&str` actually implements `Deserialize<'1>`, for some specific lifetime `'1`
+ = note: `&'static str` must implement `Deserialize<'0>`, for any lifetime `'0`...
+ = note: ...but `&str` actually implements `Deserialize<'1>`, for some specific lifetime `'1`
error: aborting due to previous error
diff --git a/src/test/ui/hrtb/issue-30786.migrate.stderr b/src/test/ui/hrtb/issue-30786.migrate.stderr
index e7deca7..c0e3fd3 100644
--- a/src/test/ui/hrtb/issue-30786.migrate.stderr
+++ b/src/test/ui/hrtb/issue-30786.migrate.stderr
@@ -1,11 +1,17 @@
error: implementation of `Stream` is not general enough
--> $DIR/issue-30786.rs:108:22
|
-LL | let map = source.map(|x: &_| x);
- | ^^^
+LL | / pub trait Stream {
+LL | | type Item;
+LL | | fn next(self) -> Option<Self::Item>;
+LL | | }
+ | |_- trait `Stream` defined here
+...
+LL | let map = source.map(|x: &_| x);
+ | ^^^ implementation of `Stream` is not general enough
|
- = note: `Stream` would have to be implemented for the type `&'0 mut Map<Repeat, [closure@$DIR/issue-30786.rs:108:26: 108:35]>`, for any lifetime `'0`
- = note: but `Stream` is actually implemented for the type `&'1 mut Map<Repeat, [closure@$DIR/issue-30786.rs:108:26: 108:35]>`, for some specific lifetime `'1`
+ = note: `Stream` would have to be implemented for the type `&'0 mut Map<Repeat, [closure@$DIR/issue-30786.rs:108:26: 108:35]>`, for any lifetime `'0`...
+ = note: ...but `Stream` is actually implemented for the type `&'1 mut Map<Repeat, [closure@$DIR/issue-30786.rs:108:26: 108:35]>`, for some specific lifetime `'1`
error: aborting due to previous error
diff --git a/src/test/ui/hrtb/issue-30786.nll.stderr b/src/test/ui/hrtb/issue-30786.nll.stderr
index 8614d86..1cfd93e 100644
--- a/src/test/ui/hrtb/issue-30786.nll.stderr
+++ b/src/test/ui/hrtb/issue-30786.nll.stderr
@@ -1,11 +1,11 @@
error: higher-ranked subtype error
- --> $DIR/issue-30786.rs:112:18
+ --> $DIR/issue-30786.rs:113:18
|
LL | let filter = map.filter(|x: &_| true);
| ^^^^^^^^^^^^^^^^^^^^^^^^
error: higher-ranked subtype error
- --> $DIR/issue-30786.rs:114:17
+ --> $DIR/issue-30786.rs:115:17
|
LL | let count = filter.count(); // Assert that we still have a valid stream.
| ^^^^^^^^^^^^^^
diff --git a/src/test/ui/hrtb/issue-30786.rs b/src/test/ui/hrtb/issue-30786.rs
index b9920a1..c42297c 100644
--- a/src/test/ui/hrtb/issue-30786.rs
+++ b/src/test/ui/hrtb/issue-30786.rs
@@ -16,7 +16,7 @@
//[nll]compile-flags: -Z borrowck=mir
-pub trait Stream {
+pub trait Stream { //[migrate]~ NOTE trait `Stream` defined here
type Item;
fn next(self) -> Option<Self::Item>;
}
@@ -109,6 +109,7 @@
//[migrate]~^ ERROR implementation of `Stream` is not general enough
//[migrate]~| NOTE `Stream` would have to be implemented for the type `&'0 mut Map
//[migrate]~| NOTE but `Stream` is actually implemented for the type `&'1
+ //[migrate]~| NOTE implementation of `Stream` is not general enough
let filter = map.filter(|x: &_| true);
//[nll]~^ ERROR higher-ranked subtype error
let count = filter.count(); // Assert that we still have a valid stream.
diff --git a/src/test/ui/issues/issue-54302-cases.stderr b/src/test/ui/issues/issue-54302-cases.stderr
index 9863761..3ed2779 100644
--- a/src/test/ui/issues/issue-54302-cases.stderr
+++ b/src/test/ui/issues/issue-54302-cases.stderr
@@ -1,38 +1,58 @@
error: implementation of `Foo` is not general enough
--> $DIR/issue-54302-cases.rs:63:5
|
-LL | <u32 as RefFoo<u32>>::ref_foo(a)
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | / trait Foo<'x, T> {
+LL | | fn foo(self) -> &'x T;
+LL | | }
+ | |_- trait `Foo` defined here
+...
+LL | <u32 as RefFoo<u32>>::ref_foo(a)
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ implementation of `Foo` is not general enough
|
- = note: `Foo<'static, u32>` would have to be implemented for the type `&'0 u32`, for any lifetime `'0`
- = note: but `Foo<'_, u32>` is actually implemented for the type `&'1 u32`, for some specific lifetime `'1`
+ = note: `Foo<'static, u32>` would have to be implemented for the type `&'0 u32`, for any lifetime `'0`...
+ = note: ...but `Foo<'_, u32>` is actually implemented for the type `&'1 u32`, for some specific lifetime `'1`
error: implementation of `Foo` is not general enough
--> $DIR/issue-54302-cases.rs:69:5
|
-LL | <i32 as RefFoo<i32>>::ref_foo(a)
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | / trait Foo<'x, T> {
+LL | | fn foo(self) -> &'x T;
+LL | | }
+ | |_- trait `Foo` defined here
+...
+LL | <i32 as RefFoo<i32>>::ref_foo(a)
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ implementation of `Foo` is not general enough
|
- = note: `Foo<'static, i32>` would have to be implemented for the type `&'0 i32`, for any lifetime `'0`
- = note: but `Foo<'_, i32>` is actually implemented for the type `&'1 i32`, for some specific lifetime `'1`
+ = note: `Foo<'static, i32>` would have to be implemented for the type `&'0 i32`, for any lifetime `'0`...
+ = note: ...but `Foo<'_, i32>` is actually implemented for the type `&'1 i32`, for some specific lifetime `'1`
error: implementation of `Foo` is not general enough
--> $DIR/issue-54302-cases.rs:75:5
|
-LL | <u64 as RefFoo<u64>>::ref_foo(a)
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | / trait Foo<'x, T> {
+LL | | fn foo(self) -> &'x T;
+LL | | }
+ | |_- trait `Foo` defined here
+...
+LL | <u64 as RefFoo<u64>>::ref_foo(a)
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ implementation of `Foo` is not general enough
|
- = note: `Foo<'static, u64>` would have to be implemented for the type `&'0 u64`, for any lifetime `'0`
- = note: but `Foo<'_, u64>` is actually implemented for the type `&'1 u64`, for some specific lifetime `'1`
+ = note: `Foo<'static, u64>` would have to be implemented for the type `&'0 u64`, for any lifetime `'0`...
+ = note: ...but `Foo<'_, u64>` is actually implemented for the type `&'1 u64`, for some specific lifetime `'1`
error: implementation of `Foo` is not general enough
--> $DIR/issue-54302-cases.rs:81:5
|
-LL | <i64 as RefFoo<i64>>::ref_foo(a)
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | / trait Foo<'x, T> {
+LL | | fn foo(self) -> &'x T;
+LL | | }
+ | |_- trait `Foo` defined here
+...
+LL | <i64 as RefFoo<i64>>::ref_foo(a)
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ implementation of `Foo` is not general enough
|
- = note: `Foo<'static, i64>` would have to be implemented for the type `&'0 i64`, for any lifetime `'0`
- = note: but `Foo<'_, i64>` is actually implemented for the type `&'1 i64`, for some specific lifetime `'1`
+ = note: `Foo<'static, i64>` would have to be implemented for the type `&'0 i64`, for any lifetime `'0`...
+ = note: ...but `Foo<'_, i64>` is actually implemented for the type `&'1 i64`, for some specific lifetime `'1`
error: aborting due to 4 previous errors
diff --git a/src/test/ui/issues/issue-54302.stderr b/src/test/ui/issues/issue-54302.stderr
index c6d0805..1b3f57b 100644
--- a/src/test/ui/issues/issue-54302.stderr
+++ b/src/test/ui/issues/issue-54302.stderr
@@ -1,11 +1,14 @@
error: implementation of `Deserialize` is not general enough
--> $DIR/issue-54302.rs:13:5
|
+LL | trait Deserialize<'de> {}
+ | ------------------------- trait `Deserialize` defined here
+...
LL | assert_deserialize_owned::<&'static str>();
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ implementation of `Deserialize` is not general enough
|
- = note: `&'static str` must implement `Deserialize<'0>`, for any lifetime `'0`
- = note: but `&str` actually implements `Deserialize<'1>`, for some specific lifetime `'1`
+ = note: `&'static str` must implement `Deserialize<'0>`, for any lifetime `'0`...
+ = note: ...but `&str` actually implements `Deserialize<'1>`, for some specific lifetime `'1`
error: aborting due to previous error
diff --git a/src/test/ui/issues/issue-55731.stderr b/src/test/ui/issues/issue-55731.stderr
index f25e18e..f44c842 100644
--- a/src/test/ui/issues/issue-55731.stderr
+++ b/src/test/ui/issues/issue-55731.stderr
@@ -1,11 +1,16 @@
error: implementation of `DistributedIteratorMulti` is not general enough
--> $DIR/issue-55731.rs:48:5
|
-LL | multi(Map {
- | ^^^^^
+LL | / trait DistributedIteratorMulti<Source> {
+LL | | type Item;
+LL | | }
+ | |_- trait `DistributedIteratorMulti` defined here
+...
+LL | multi(Map {
+ | ^^^^^ implementation of `DistributedIteratorMulti` is not general enough
|
- = note: `DistributedIteratorMulti<&'0 ()>` would have to be implemented for the type `Cloned<&()>`, for any lifetime `'0`
- = note: but `DistributedIteratorMulti<&'1 ()>` is actually implemented for the type `Cloned<&'1 ()>`, for some specific lifetime `'1`
+ = note: `DistributedIteratorMulti<&'0 ()>` would have to be implemented for the type `Cloned<&()>`, for any lifetime `'0`...
+ = note: ...but `DistributedIteratorMulti<&'1 ()>` is actually implemented for the type `Cloned<&'1 ()>`, for some specific lifetime `'1`
error: aborting due to previous error
diff --git a/src/test/ui/lifetimes/lifetime-errors/ex3-both-anon-regions-3.nll.stderr b/src/test/ui/lifetimes/lifetime-errors/ex3-both-anon-regions-3.nll.stderr
index 779e2eb..2ed4d6d 100644
--- a/src/test/ui/lifetimes/lifetime-errors/ex3-both-anon-regions-3.nll.stderr
+++ b/src/test/ui/lifetimes/lifetime-errors/ex3-both-anon-regions-3.nll.stderr
@@ -12,11 +12,11 @@
--> $DIR/ex3-both-anon-regions-3.rs:2:5
|
LL | fn foo(z: &mut Vec<(&u8,&u8)>, (x, y): (&u8, &u8)) {
- | - - let's call the lifetime of this reference `'1`
+ | - - let's call the lifetime of this reference `'3`
| |
- | let's call the lifetime of this reference `'2`
+ | let's call the lifetime of this reference `'4`
LL | z.push((x,y));
- | ^^^^^^^^^^^^^ argument requires that `'1` must outlive `'2`
+ | ^^^^^^^^^^^^^ argument requires that `'3` must outlive `'4`
error: aborting due to 2 previous errors
