Auto merge of #28689 - Manishearth:rollup, r=Manishearth

- Successful merges: #28664, #28673, #28681, #28682, #28688
- Failed merges:

src/libcollections/enum_set.rs

@@ -49,16 +49,7 @@ impl<E> Clone for EnumSet<E> {
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<E:CLike + fmt::Debug> fmt::Debug for EnumSet<E> {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        try!(write!(fmt, "{{"));
-        let mut first = true;
-        for e in self {
-            if !first {
-                try!(write!(fmt, ", "));
-            }
-            try!(write!(fmt, "{:?}", e));
-            first = false;
-        }
-        write!(fmt, "}}")
+        fmt.debug_set().entries(self).finish()
     }
 }
 

src/libcollections/str.rs

@@ -506,8 +506,6 @@ impl str {
     ///
     /// # Examples
     /// ```
-    /// #![feature(str_split_at)]
-    ///
     /// let s = "Löwe 老虎 Léopard";
     /// let first_space = s.find(' ').unwrap_or(s.len());
     /// let (a, b) = s.split_at(first_space);

src/libcollections/vec.rs

@@ -753,8 +753,6 @@ impl<T> Vec<T> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(split_off)]
-    ///
     /// let mut vec = vec![1,2,3];
     /// let vec2 = vec.split_off(1);
     /// assert_eq!(vec, [1]);

src/libcollections/vec_deque.rs

@@ -1319,8 +1319,6 @@ impl<T> VecDeque<T> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(split_off)]
-    ///
     /// use std::collections::VecDeque;
     ///
     /// let mut buf: VecDeque<_> = vec![1,2,3].into_iter().collect();
@@ -1406,8 +1404,6 @@ impl<T> VecDeque<T> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(vec_deque_retain)]
-    ///
     /// use std::collections::VecDeque;
     ///
     /// let mut buf = VecDeque::new();
@@ -1787,14 +1783,7 @@ impl<'a, T: 'a + Copy> Extend<&'a T> for VecDeque<T> {
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: fmt::Debug> fmt::Debug for VecDeque<T> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        try!(write!(f, "["));
-
-        for (i, e) in self.iter().enumerate() {
-            if i != 0 { try!(write!(f, ", ")); }
-            try!(write!(f, "{:?}", *e));
-        }
-
-        write!(f, "]")
+        f.debug_list().entries(self).finish()
     }
 }
 

src/libcollectionstest/lib.rs

@@ -9,7 +9,6 @@
 // except according to those terms.
 
 #![feature(ascii)]
-#![feature(append)]
 #![feature(binary_heap_extras)]
 #![feature(box_syntax)]
 #![feature(btree_range)]
@@ -29,18 +28,14 @@
 #![feature(set_recovery)]
 #![feature(slice_bytes)]
 #![feature(slice_splits)]
-#![feature(split_off)]
 #![feature(step_by)]
 #![feature(str_char)]
 #![feature(str_escape)]
 #![feature(str_match_indices)]
-#![feature(str_split_at)]
 #![feature(str_utf16)]
-#![feature(box_str)]
 #![feature(test)]
 #![feature(unboxed_closures)]
 #![feature(unicode)]
-#![feature(vec_deque_retain)]
 #![feature(vec_push_all)]
 
 #[macro_use] extern crate log;

src/librustc/middle/infer/mod.rs

@@ -43,7 +43,7 @@ use std::rc::Rc;
 use syntax::ast;
 use syntax::codemap;
 use syntax::codemap::{Span, DUMMY_SP};
-use util::nodemap::{FnvHashMap, NodeMap};
+use util::nodemap::{FnvHashMap, FnvHashSet, NodeMap};
 
 use self::combine::CombineFields;
 use self::region_inference::{RegionVarBindings, RegionSnapshot};
@@ -92,6 +92,10 @@ pub struct InferCtxt<'a, 'tcx: 'a> {
 
     pub fulfillment_cx: RefCell<traits::FulfillmentContext<'tcx>>,
 
+    // the set of predicates on which errors have been reported, to
+    // avoid reporting the same error twice.
+    pub reported_trait_errors: RefCell<FnvHashSet<traits::TraitErrorKey<'tcx>>>,
+
     // This is a temporary field used for toggling on normalization in the inference context,
     // as we move towards the approach described here:
     // https://internals.rust-lang.org/t/flattening-the-contexts-for-fun-and-profit/2293
@@ -374,6 +378,7 @@ pub fn new_infer_ctxt<'a, 'tcx>(tcx: &'a ty::ctxt<'tcx>,
         region_vars: RegionVarBindings::new(tcx),
         parameter_environment: param_env.unwrap_or(tcx.empty_parameter_environment()),
         fulfillment_cx: RefCell::new(traits::FulfillmentContext::new(errors_will_be_reported)),
+        reported_trait_errors: RefCell::new(FnvHashSet()),
         normalize: false,
         err_count_on_creation: tcx.sess.err_count()
     }

src/librustc/middle/reachable.rs

@@ -348,13 +348,17 @@ impl<'a, 'tcx> ReachableContext<'a, 'tcx> {
     // this properly would result in the necessity of computing *type*
     // reachability, which might result in a compile time loss.
     fn mark_destructors_reachable(&mut self) {
-        for adt in self.tcx.adt_defs() {
-            if let Some(destructor_def_id) = adt.destructor() {
-                if destructor_def_id.is_local() {
-                    self.reachable_symbols.insert(destructor_def_id.node);
+        let drop_trait = match self.tcx.lang_items.drop_trait() {
+            Some(id) => self.tcx.lookup_trait_def(id), None => { return }
+        };
+        drop_trait.for_each_impl(self.tcx, |drop_impl| {
+            for destructor in &self.tcx.impl_items.borrow()[&drop_impl] {
+                let destructor_did = destructor.def_id();
+                if destructor_did.is_local() {
+                    self.reachable_symbols.insert(destructor_did.node);
                 }
             }
-        }
+        })
     }
 }
 

src/librustc/middle/traits/error_reporting.rs

@@ -28,11 +28,32 @@ use middle::def_id::DefId;
 use middle::infer::InferCtxt;
 use middle::ty::{self, ToPredicate, HasTypeFlags, ToPolyTraitRef, TraitRef, Ty};
 use middle::ty::fold::TypeFoldable;
-use std::collections::HashMap;
+use util::nodemap::{FnvHashMap, FnvHashSet};
+
 use std::fmt;
 use syntax::codemap::Span;
 use syntax::attr::{AttributeMethods, AttrMetaMethods};
 
+#[derive(Debug, PartialEq, Eq, Hash)]
+pub struct TraitErrorKey<'tcx> {
+    is_warning: bool,
+    span: Span,
+    predicate: ty::Predicate<'tcx>
+}
+
+impl<'tcx> TraitErrorKey<'tcx> {
+    fn from_error<'a>(infcx: &InferCtxt<'a, 'tcx>,
+                      e: &FulfillmentError<'tcx>) -> Self {
+        let predicate =
+            infcx.resolve_type_vars_if_possible(&e.obligation.predicate);
+        TraitErrorKey {
+            is_warning: is_warning(&e.obligation),
+            span: e.obligation.cause.span,
+            predicate: infcx.tcx.erase_regions(&predicate)
+        }
+    }
+}
+
 pub fn report_fulfillment_errors<'a, 'tcx>(infcx: &InferCtxt<'a, 'tcx>,
                                            errors: &Vec<FulfillmentError<'tcx>>) {
     for error in errors {
@@ -42,6 +63,13 @@ pub fn report_fulfillment_errors<'a, 'tcx>(infcx: &InferCtxt<'a, 'tcx>,
 
 fn report_fulfillment_error<'a, 'tcx>(infcx: &InferCtxt<'a, 'tcx>,
                                       error: &FulfillmentError<'tcx>) {
+    let error_key = TraitErrorKey::from_error(infcx, error);
+    debug!("report_fulfillment_errors({:?}) - key={:?}",
+           error, error_key);
+    if !infcx.reported_trait_errors.borrow_mut().insert(error_key) {
+        debug!("report_fulfillment_errors: skipping duplicate");
+        return;
+    }
     match error.code {
         FulfillmentErrorCode::CodeSelectionError(ref e) => {
             report_selection_error(infcx, &error.obligation, e);
@@ -97,7 +125,7 @@ fn report_on_unimplemented<'a, 'tcx>(infcx: &InferCtxt<'a, 'tcx>,
                                                (gen.name.as_str().to_string(),
                                                 trait_ref.substs.types.get(param, i)
                                                          .to_string())
-                                              }).collect::<HashMap<String, String>>();
+                                              }).collect::<FnvHashMap<String, String>>();
                 generic_map.insert("Self".to_string(),
                                    trait_ref.self_ty().to_string());
                 let parser = Parser::new(&istring);
@@ -308,7 +336,11 @@ pub fn report_object_safety_error<'tcx>(tcx: &ty::ctxt<'tcx>,
         "the trait `{}` cannot be made into an object",
         tcx.item_path_str(trait_def_id));
 
+    let mut reported_violations = FnvHashSet();
     for violation in violations {
+        if !reported_violations.insert(violation.clone()) {
+            continue;
+        }
         match violation {
             ObjectSafetyViolation::SizedSelf => {
                 tcx.sess.fileline_note(

src/librustc/middle/traits/fulfill.rs

@@ -49,6 +49,12 @@ pub struct FulfillmentContext<'tcx> {
     // than the `SelectionCache`: it avoids duplicate errors and
     // permits recursive obligations, which are often generated from
     // traits like `Send` et al.
+    //
+    // Note that because of type inference, a predicate can still
+    // occur twice in the predicates list, for example when 2
+    // initially-distinct type variables are unified after being
+    // inserted. Deduplicating the predicate set on selection had a
+    // significant performance cost the last time I checked.
     duplicate_set: FulfilledPredicates<'tcx>,
 
     // A list of all obligations that have been registered with this

src/librustc/middle/traits/mod.rs

@@ -21,10 +21,12 @@ use middle::subst;
 use middle::ty::{self, HasTypeFlags, Ty};
 use middle::ty::fold::TypeFoldable;
 use middle::infer::{self, fixup_err_to_string, InferCtxt};
+
 use std::rc::Rc;
 use syntax::ast;
 use syntax::codemap::{Span, DUMMY_SP};
 
+pub use self::error_reporting::TraitErrorKey;
 pub use self::error_reporting::report_fulfillment_errors;
 pub use self::error_reporting::report_overflow_error;
 pub use self::error_reporting::report_selection_error;

src/librustc/middle/traits/object_safety.rs

@@ -27,7 +27,7 @@ use middle::ty::{self, ToPolyTraitRef, Ty};
 use std::rc::Rc;
 use syntax::ast;
 
-#[derive(Debug)]
+#[derive(Clone, Debug, PartialEq, Eq, Hash)]
 pub enum ObjectSafetyViolation<'tcx> {
     /// Self : Sized declared on the trait
     SizedSelf,

src/librustc/middle/ty/context.rs

@@ -245,9 +245,6 @@ pub struct ctxt<'tcx> {
     /// True if the variance has been computed yet; false otherwise.
     pub variance_computed: Cell<bool>,
 
-    /// A method will be in this list if and only if it is a destructor.
-    pub destructors: RefCell<DefIdSet>,
-
     /// Maps a DefId of a type to a list of its inherent impls.
     /// Contains implementations of methods that are inherent to a type.
     /// Methods in these implementations don't need to be exported.
@@ -475,7 +472,6 @@ impl<'tcx> ctxt<'tcx> {
             normalized_cache: RefCell::new(FnvHashMap()),
             lang_items: lang_items,
             provided_method_sources: RefCell::new(DefIdMap()),
-            destructors: RefCell::new(DefIdSet()),
             inherent_impls: RefCell::new(DefIdMap()),
             impl_items: RefCell::new(DefIdMap()),
             used_unsafe: RefCell::new(NodeSet()),

src/librustc/middle/ty/mod.rs

@@ -272,6 +272,20 @@ impl<'tcx> Method<'tcx> {
     }
 }
 
+impl<'tcx> PartialEq for Method<'tcx> {
+    #[inline]
+    fn eq(&self, other: &Self) -> bool { self.def_id == other.def_id }
+}
+
+impl<'tcx> Eq for Method<'tcx> {}
+
+impl<'tcx> Hash for Method<'tcx> {
+    #[inline]
+    fn hash<H: Hasher>(&self, s: &mut H) {
+        self.def_id.hash(s)
+    }
+}
+
 #[derive(Clone, Copy, Debug)]
 pub struct AssociatedConst<'tcx> {
     pub name: Name,
@@ -1681,7 +1695,6 @@ impl<'tcx, 'container> AdtDefData<'tcx, 'container> {
     }
 
     pub fn set_destructor(&self, dtor: DefId) {
-        assert!(self.destructor.get().is_none());
         self.destructor.set(Some(dtor));
     }
 
@@ -2315,11 +2328,6 @@ impl<'tcx> ctxt<'tcx> {
         self.lookup_adt_def_master(did)
     }
 
-    /// Return the list of all interned ADT definitions
-    pub fn adt_defs(&self) -> Vec<AdtDef<'tcx>> {
-        self.adt_defs.borrow().values().cloned().collect()
-    }
-
     /// Given the did of an item, returns its full set of predicates.
     pub fn lookup_predicates(&self, did: DefId) -> GenericPredicates<'tcx> {
         lookup_locally_or_in_crate_store(

src/librustc_front/lib.rs

@@ -36,7 +36,6 @@
 #![feature(staged_api)]
 #![feature(str_char)]
 #![feature(filling_drop)]
-#![cfg_attr(test, feature(test))]
 
 extern crate serialize;
 #[macro_use] extern crate log;

src/librustc_lint/builtin.rs

@@ -1210,15 +1210,14 @@ impl LintPass for DropWithReprExtern {
 
 impl LateLintPass for DropWithReprExtern {
     fn check_crate(&mut self, ctx: &LateContext, _: &hir::Crate) {
-        for dtor_did in ctx.tcx.destructors.borrow().iter() {
-            let (drop_impl_did, dtor_self_type) =
-                if dtor_did.is_local() {
-                    let impl_did = ctx.tcx.map.get_parent_did(dtor_did.node);
-                    let ty = ctx.tcx.lookup_item_type(impl_did).ty;
-                    (impl_did, ty)
-                } else {
-                    continue;
-                };
+        let drop_trait = match ctx.tcx.lang_items.drop_trait() {
+            Some(id) => ctx.tcx.lookup_trait_def(id), None => { return }
+        };
+        drop_trait.for_each_impl(ctx.tcx, |drop_impl_did| {
+            if !drop_impl_did.is_local() {
+                return;
+            }
+            let dtor_self_type = ctx.tcx.lookup_item_type(drop_impl_did).ty;
 
             match dtor_self_type.sty {
                 ty::TyEnum(self_type_def, _) |
@@ -1244,6 +1243,6 @@ impl LateLintPass for DropWithReprExtern {
                 }
                 _ => {}
             }
-        }
+        })
     }
 }

src/librustc_trans/back/archive.rs

@@ -145,10 +145,13 @@ impl<'a> ArchiveBuilder<'a> {
 
     /// Adds all of the contents of a native library to this archive. This will
     /// search in the relevant locations for a library named `name`.
-    pub fn add_native_library(&mut self, name: &str) -> io::Result<()> {
+    pub fn add_native_library(&mut self, name: &str) {
         let location = find_library(name, &self.config.lib_search_paths,
                                     self.config.sess);
-        self.add_archive(&location, name, |_| false)
+        self.add_archive(&location, name, |_| false).unwrap_or_else(|e| {
+            self.config.sess.fatal(&format!("failed to add native library {}: {}",
+                                            location.to_string_lossy(), e));
+        });
     }
 
     /// Adds all of the contents of the rlib at the specified path to this

src/librustc_trans/back/link.rs

@@ -616,7 +616,7 @@ fn link_rlib<'a>(sess: &'a Session,
 
     for &(ref l, kind) in sess.cstore.get_used_libraries().borrow().iter() {
         match kind {
-            cstore::NativeStatic => ab.add_native_library(&l).unwrap(),
+            cstore::NativeStatic => ab.add_native_library(&l),
             cstore::NativeFramework | cstore::NativeUnknown => {}
         }
     }
@@ -792,7 +792,7 @@ fn link_staticlib(sess: &Session, objects: &[PathBuf], out_filename: &Path,
         ab.build();
     }
     if !sess.target.target.options.no_compiler_rt {
-        ab.add_native_library("compiler-rt").unwrap();
+        ab.add_native_library("compiler-rt");
     }
 
     let mut all_native_libs = vec![];

src/librustc_typeck/check/method/confirm.rs

@@ -620,13 +620,7 @@ impl<'a,'tcx> ConfirmContext<'a,'tcx> {
             ty::TraitContainer(trait_def_id) => {
                 callee::check_legal_trait_for_method_call(self.fcx.ccx, self.span, trait_def_id)
             }
-            ty::ImplContainer(..) => {
-                // Since `drop` is a trait method, we expect that any
-                // potential calls to it will wind up in the other
-                // arm. But just to be sure, check that the method id
-                // does not appear in the list of destructors.
-                assert!(!self.tcx().destructors.borrow().contains(&pick.item.def_id()));
-            }
+            ty::ImplContainer(..) => {}
         }
     }