Auto merge of #48399 - GuillaumeGomez:rollup, r=GuillaumeGomez

Rollup of 12 pull requests

- Successful merges: #47379, #47833, #48106, #48198, #48314, #48325, #48335, #48352, #48354, #48360, #48382, #48397
- Failed merges:

Author: bors

.mailmap

@@ -95,9 +95,9 @@ Herman J. Radtke III <herman@hermanradtke.com> Herman J. Radtke III <hermanradtk
 Ilyong Cho <ilyoan@gmail.com>
 Ivan Ivaschenko <defuz.net@gmail.com>
 J. J. Weber <jjweber@gmail.com>
-Jakub Bukaj <jakub@jakub.cc>
-Jakub Bukaj <jakub@jakub.cc> <jakubw@jakubw.net>
-Jakub Bukaj <jakub@jakub.cc> Jakub Bukaj <jakub.bukaj@yahoo.com>
+Jakub Adam Wieczorek <jakub.adam.wieczorek@gmail.com> <jakub@jakub.cc>
+Jakub Adam Wieczorek <jakub.adam.wieczorek@gmail.com> <jakubw@jakubw.net>
+Jakub Adam Wieczorek <jakub.adam.wieczorek@gmail.com> <jakub.bukaj@yahoo.com>
 James Deng <cnjamesdeng@gmail.com> <cnJamesDeng@gmail.com>
 James Miller <bladeon@gmail.com> <james@aatch.net>
 James Perry <james.austin.perry@gmail.com>

src/Cargo.lock

@@ -343,7 +343,7 @@ impl Ordering {
 /// v.sort_by_key(|&num| (num > 3, Reverse(num)));
 /// assert_eq!(v, vec![3, 2, 1, 6, 5, 4]);
 /// ```
-#[derive(PartialEq, Eq, Debug)]
+#[derive(PartialEq, Eq, Debug, Copy, Clone)]
 #[stable(feature = "reverse_cmp_key", since = "1.19.0")]
 pub struct Reverse<T>(#[stable(feature = "reverse_cmp_key", since = "1.19.0")] pub T);
 

src/libcore/cmp.rs

@@ -168,7 +168,7 @@ pub trait Iterator {
     /// This function might panic if the iterator has more than [`usize::MAX`]
     /// elements.
     ///
-    /// [`usize::MAX`]: ../../std/isize/constant.MAX.html
+    /// [`usize::MAX`]: ../../std/usize/constant.MAX.html
     ///
     /// # Examples
     ///

src/libcore/iter/iterator.rs

@@ -1209,7 +1209,7 @@ Basic usage:
 ```
 ", $Feature, "let x: ", stringify!($SelfT), " = 2; // or any other integer type
 
-assert_eq!(x.pow(4), 16);",
+assert_eq!(x.pow(5), 32);",
 $EndFeature, "
 ```"),
             #[stable(feature = "rust1", since = "1.0.0")]
@@ -2364,7 +2364,7 @@ assert_eq!(0x10", stringify!($SelfT), ".overflowing_shr(132), (0x1, true));", $E
 Basic usage:
 
 ```
-", $Feature, "assert_eq!(2", stringify!($SelfT), ".pow(4), 16);", $EndFeature, "
+", $Feature, "assert_eq!(2", stringify!($SelfT), ".pow(5), 32);", $EndFeature, "
 ```"),
         #[stable(feature = "rust1", since = "1.0.0")]
         #[inline]

src/libcore/num/mod.rs

@@ -72,6 +72,10 @@ impl DefPathTable {
         index
     }
 
+    pub fn next_id(&self, address_space: DefIndexAddressSpace) -> DefIndex {
+        DefIndex::from_array_index(self.index_to_key[address_space.index()].len(), address_space)
+    }
+
     #[inline(always)]
     pub fn def_key(&self, index: DefIndex) -> DefKey {
         self.index_to_key[index.address_space().index()]

src/librustc/hir/map/definitions.rs

@@ -180,7 +180,7 @@ pub struct InferCtxt<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {
     // for each body-id in this map, which will process the
     // obligations within. This is expected to be done 'late enough'
     // that all type inference variables have been bound and so forth.
-    region_obligations: RefCell<Vec<(ast::NodeId, RegionObligation<'tcx>)>>,
+    pub region_obligations: RefCell<Vec<(ast::NodeId, RegionObligation<'tcx>)>>,
 }
 
 /// A map returned by `skolemize_late_bound_regions()` indicating the skolemized
@@ -1555,11 +1555,20 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
         InferOk { value, obligations }
     }
 
-    fn borrow_region_constraints(&self) -> RefMut<'_, RegionConstraintCollector<'tcx>> {
+    pub fn borrow_region_constraints(&self) -> RefMut<'_, RegionConstraintCollector<'tcx>> {
         RefMut::map(
             self.region_constraints.borrow_mut(),
             |c| c.as_mut().expect("region constraints already solved"))
     }
+
+    /// Clears the selection, evaluation, and projection cachesThis is useful when
+    /// repeatedly attemping to select an Obligation while changing only
+    /// its ParamEnv, since FulfillmentContext doesn't use 'probe'
+    pub fn clear_caches(&self) {
+        self.selection_cache.clear();
+        self.evaluation_cache.clear();
+        self.projection_cache.borrow_mut().clear();
+    }
 }
 
 impl<'a, 'gcx, 'tcx> TypeTrace<'tcx> {

src/librustc/infer/mod.rs

@@ -82,7 +82,7 @@ pub type VarOrigins = IndexVec<RegionVid, RegionVariableOrigin>;
 /// Describes constraints between the region variables and other
 /// regions, as well as other conditions that must be verified, or
 /// assumptions that can be made.
-#[derive(Debug, Default)]
+#[derive(Debug, Default, Clone)]
 pub struct RegionConstraintData<'tcx> {
     /// Constraints of the form `A <= B`, where either `A` or `B` can
     /// be a region variable (or neither, as it happens).
@@ -142,7 +142,7 @@ pub enum Constraint<'tcx> {
 /// outlive `RS`. Therefore verify that `R <= RS[i]` for some
 /// `i`. Inference variables may be involved (but this verification
 /// step doesn't influence inference).
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct Verify<'tcx> {
     pub kind: GenericKind<'tcx>,
     pub origin: SubregionOrigin<'tcx>,
@@ -159,7 +159,7 @@ pub enum GenericKind<'tcx> {
 /// When we introduce a verification step, we wish to test that a
 /// particular region (let's call it `'min`) meets some bound.
 /// The bound is described the by the following grammar:
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub enum VerifyBound<'tcx> {
     /// B = exists {R} --> some 'r in {R} must outlive 'min
     ///
@@ -288,6 +288,10 @@ impl<'tcx> RegionConstraintCollector<'tcx> {
         &self.var_origins
     }
 
+    pub fn region_constraint_data(&self) -> &RegionConstraintData<'tcx> {
+        &self.data
+    }
+
     /// Once all the constraints have been gathered, extract out the final data.
     ///
     /// Not legal during a snapshot.

src/librustc/infer/region_constraints/mod.rs

@@ -32,8 +32,8 @@ use syntax_pos::{Span, DUMMY_SP};
 pub use self::coherence::{orphan_check, overlapping_impls, OrphanCheckErr, OverlapResult};
 pub use self::fulfill::FulfillmentContext;
 pub use self::project::MismatchedProjectionTypes;
-pub use self::project::{normalize, normalize_projection_type, Normalized};
-pub use self::project::{ProjectionCache, ProjectionCacheSnapshot, Reveal};
+pub use self::project::{normalize, normalize_projection_type, poly_project_and_unify_type};
+pub use self::project::{ProjectionCache, ProjectionCacheSnapshot, Reveal, Normalized};
 pub use self::object_safety::ObjectSafetyViolation;
 pub use self::object_safety::MethodViolationCode;
 pub use self::on_unimplemented::{OnUnimplementedDirective, OnUnimplementedNote};

src/librustc/traits/mod.rs

@@ -1596,6 +1596,10 @@ impl<'tcx> ProjectionCache<'tcx> {
         }
     }
 
+    pub fn clear(&mut self) {
+        self.map.clear();
+    }
+
     pub fn snapshot(&mut self) -> ProjectionCacheSnapshot {
         ProjectionCacheSnapshot { snapshot: self.map.snapshot() }
     }

src/librustc/traits/project.rs

@@ -93,6 +93,11 @@ pub struct SelectionContext<'cx, 'gcx: 'cx+'tcx, 'tcx: 'cx> {
     inferred_obligations: SnapshotVec<InferredObligationsSnapshotVecDelegate<'tcx>>,
 
     intercrate_ambiguity_causes: Option<Vec<IntercrateAmbiguityCause>>,
+
+    /// Controls whether or not to filter out negative impls when selecting.
+    /// This is used in librustdoc to distinguish between the lack of an impl
+    /// and a negative impl
+    allow_negative_impls: bool
 }
 
 #[derive(Clone, Debug)]
@@ -424,6 +429,7 @@ impl<'cx, 'gcx, 'tcx> SelectionContext<'cx, 'gcx, 'tcx> {
             intercrate: None,
             inferred_obligations: SnapshotVec::new(),
             intercrate_ambiguity_causes: None,
+            allow_negative_impls: false,
         }
     }
 
@@ -436,6 +442,20 @@ impl<'cx, 'gcx, 'tcx> SelectionContext<'cx, 'gcx, 'tcx> {
             intercrate: Some(mode),
             inferred_obligations: SnapshotVec::new(),
             intercrate_ambiguity_causes: None,
+            allow_negative_impls: false,
+        }
+    }
+
+    pub fn with_negative(infcx: &'cx InferCtxt<'cx, 'gcx, 'tcx>,
+                         allow_negative_impls: bool) -> SelectionContext<'cx, 'gcx, 'tcx> {
+        debug!("with_negative({:?})", allow_negative_impls);
+        SelectionContext {
+            infcx,
+            freshener: infcx.freshener(),
+            intercrate: None,
+            inferred_obligations: SnapshotVec::new(),
+            intercrate_ambiguity_causes: None,
+            allow_negative_impls,
         }
     }
 
@@ -1086,7 +1106,8 @@ impl<'cx, 'gcx, 'tcx> SelectionContext<'cx, 'gcx, 'tcx> {
     fn filter_negative_impls(&self, candidate: SelectionCandidate<'tcx>)
                              -> SelectionResult<'tcx, SelectionCandidate<'tcx>> {
         if let ImplCandidate(def_id) = candidate {
-            if self.tcx().impl_polarity(def_id) == hir::ImplPolarity::Negative {
+            if !self.allow_negative_impls &&
+                self.tcx().impl_polarity(def_id) == hir::ImplPolarity::Negative {
                 return Err(Unimplemented)
             }
         }
@@ -3337,6 +3358,10 @@ impl<'tcx> SelectionCache<'tcx> {
             hashmap: RefCell::new(FxHashMap())
         }
     }
+
+    pub fn clear(&self) {
+        *self.hashmap.borrow_mut() = FxHashMap()
+    }
 }
 
 impl<'tcx> EvaluationCache<'tcx> {
@@ -3345,6 +3370,10 @@ impl<'tcx> EvaluationCache<'tcx> {
             hashmap: RefCell::new(FxHashMap())
         }
     }
+
+    pub fn clear(&self) {
+        *self.hashmap.borrow_mut() = FxHashMap()
+    }
 }
 
 impl<'o,'tcx> TraitObligationStack<'o,'tcx> {

src/librustc/traits/select.rs

@@ -45,6 +45,11 @@ impl<K, V> SnapshotMap<K, V>
         }
     }
 
+    pub fn clear(&mut self) {
+        self.map.clear();
+        self.undo_log.clear();
+    }
+
     pub fn insert(&mut self, key: K, value: V) -> bool {
         match self.map.insert(key.clone(), value) {
             None => {

src/librustc_data_structures/snapshot_map/mod.rs

@@ -325,6 +325,8 @@ Erroneous code example:
 extern crate core;
 
 struct core;
+
+fn main() {}
 ```
 
 There are two possible solutions:

src/librustc_resolve/diagnostics.rs

@@ -337,7 +337,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                                 lint::builtin::TYVAR_BEHIND_RAW_POINTER,
                                 scope_expr_id,
                                 span,
-                                &format!("the type of this value must be known in this context"));
+                                &format!("type annotations needed"));
                         }
                     } else {
                         let t = self.structurally_resolved_type(span, final_ty);

src/librustc_typeck/check/method/probe.rs

@@ -5052,9 +5052,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
             ty
         } else {
             if !self.is_tainted_by_errors() {
-                type_error_struct!(self.tcx.sess, sp, ty, E0619,
-                                    "the type of this value must be known in this context")
-                .emit();
+                self.need_type_info((**self).body_id, sp, ty);
             }
             self.demand_suptype(sp, self.tcx.types.err, ty);
             self.tcx.types.err

src/librustc_typeck/check/mod.rs

@@ -4368,12 +4368,13 @@ i_am_a_function();
 "##,
 
 E0619: r##"
+#### Note: this error code is no longer emitted by the compiler.
 The type-checker needed to know the type of an expression, but that type had not
 yet been inferred.
 
 Erroneous code example:
 
-```compile_fail,E0619
+```compile_fail
 let mut x = vec![];
 match x.pop() {
     Some(v) => {

src/librustc_typeck/diagnostics.rs

@@ -10,5 +10,5 @@ path = "lib.rs"
 doctest = false
 
 [dependencies]
-pulldown-cmark = { version = "0.1.0", default-features = false }
+pulldown-cmark = { version = "0.1.2", default-features = false }
 tempdir = "0.3"