Rollup of 10 pull requests

CONTRIBUTING.md

@@ -15,7 +15,7 @@ links to the major sections:
 * [Helpful Links and Information](#helpful-links-and-information)
 
 If you have questions, please make a post on [internals.rust-lang.org][internals] or
-hop on [#rust-internals][pound-rust-internals].
+hop on the [Rust Discord server][rust-discord], [Rust Zulip server][rust-zulip] or [#rust-internals][pound-rust-internals].
 
 As a reminder, all contributors are expected to follow our [Code of Conduct][coc].
 
@@ -27,14 +27,17 @@ can give you a good example of how a typical contribution would go.
 
 [pound-rust-internals]: https://chat.mibbit.com/?server=irc.mozilla.org&channel=%23rust-internals
 [internals]: https://internals.rust-lang.org
+[rust-discord]: http://discord.gg/rust-lang
+[rust-zulip]: https://rust-lang.zulipchat.com
 [coc]: https://www.rust-lang.org/conduct.html
+[rustc-guide]: https://rust-lang.github.io/rustc-guide/
 [walkthrough]: https://rust-lang.github.io/rustc-guide/walkthrough.html
 
 ## Feature Requests
 [feature-requests]: #feature-requests
 
 To request a change to the way the Rust language works, please head over
-to the [RFCs repository](https://github.com/rust-lang/rfcs) and view the 
+to the [RFCs repository](https://github.com/rust-lang/rfcs) and view the
 [README](https://github.com/rust-lang/rfcs/blob/master/README.md)
 for instructions.
 
@@ -129,28 +132,40 @@ request); you can add [git hooks](https://git-scm.com/book/en/v2/Customizing-Git
 before every push to make sure you never forget to make this check.
 
 All pull requests are reviewed by another person. We have a bot,
-@rust-highfive, that will automatically assign a random person to review your
+[@rust-highfive][rust-highfive], that will automatically assign a random person to review your
 request.
 
 If you want to request that a specific person reviews your pull request,
-you can add an `r?` to the message. For example, Steve usually reviews
+you can add an `r?` to the message. For example, [Steve][steveklabnik] usually reviews
 documentation changes. So if you were to make a documentation change, add
 
     r? @steveklabnik
 
-to the end of the message, and @rust-highfive will assign @steveklabnik instead
+to the end of the message, and @rust-highfive will assign [@steveklabnik][steveklabnik] instead
 of a random person. This is entirely optional.
 
 After someone has reviewed your pull request, they will leave an annotation
 on the pull request with an `r+`. It will look something like this:
 
-    @bors: r+ 38fe8d2
+    @bors r+
 
-This tells @bors, our lovable integration bot, that your pull request has
-been approved. The PR then enters the [merge queue][merge-queue], where @bors
+This tells [@bors][bors], our lovable integration bot, that your pull request has
+been approved. The PR then enters the [merge queue][merge-queue], where [@bors][bors]
 will run all the tests on every platform we support. If it all works out,
-@bors will merge your code into `master` and close the pull request.
+[@bors][bors] will merge your code into `master` and close the pull request.
 
+Depending on the scale of the change, you may see a slightly different form of `r+`:
+
+    @bors r+ rollup
+
+The additional `rollup` tells [@bors][bors] that this change is eligible for to be
+"rolled up". Changes that are rolled up are tested and merged at the same time, to
+speed the process up. Typically only small changes that are expected not to conflict
+with one another are rolled up.
+
+[rust-highfive]: https://github.com/rust-highfive
+[steveklabnik]: https://github.com/steveklabnik
+[bors]: https://github.com/bors
 [merge-queue]: https://buildbot2.rust-lang.org/homu/queue/rust
 
 Speaking of tests, Rust has a comprehensive test suite. More information about
@@ -190,7 +205,7 @@ before the PR is merged.
 [breaking-tools-built-with-the-compiler]: #breaking-tools-built-with-the-compiler
 
 Rust's build system builds a number of tools that make use of the
-internals of the compiler. This includes 
+internals of the compiler. This includes
 [Clippy](https://github.com/rust-lang/rust-clippy),
 [RLS](https://github.com/rust-lang/rls) and
 [rustfmt](https://github.com/rust-lang/rustfmt). If these tools
@@ -292,18 +307,8 @@ the submodule to. Running `./x.py build` should work now.
 
 Documentation improvements are very welcome. The source of `doc.rust-lang.org`
 is located in `src/doc` in the tree, and standard API documentation is generated
-from the source code itself.
-
-Documentation pull requests function in the same way as other pull requests,
-though you may see a slightly different form of `r+`:
-
-    @bors: r+ 38fe8d2 rollup
-
-That additional `rollup` tells @bors that this change is eligible for a 'rollup'.
-To save @bors some work, and to get small changes through more quickly, when
-@bors attempts to merge a commit that's rollup-eligible, it will also merge
-the other rollup-eligible patches too, and they'll get tested and merged at
-the same time.
+from the source code itself. Documentation pull requests function in the same way
+as other pull requests.
 
 To find documentation-related issues, sort by the [T-doc label][tdoc].
 
@@ -428,7 +433,8 @@ are:
 * Although out of date, [Tom Lee's great blog article][tlgba] is very helpful
 * [rustaceans.org][ro] is helpful, but mostly dedicated to IRC
 * The [Rust Compiler Testing Docs][rctd]
-* For @bors, [this cheat sheet][cheatsheet] is helpful (Remember to replace `@homu` with `@bors` in the commands that you use.)
+* For [@bors][bors], [this cheat sheet][cheatsheet] is helpful
+(though you'll need to replace `@homu` with `@bors` in any commands)
 * **Google!** ([search only in Rust Documentation][gsearchdocs] to find types, traits, etc. quickly)
 * Don't be afraid to ask! The Rust community is friendly and helpful.
 

src/libcore/hint.rs

@@ -2,7 +2,7 @@
 
 //! Hints to compiler that affects how code should be emitted or optimized.
 
-use intrinsics;
+use {arch, intrinsics};
 
 /// Informs the compiler that this point in the code is not reachable, enabling
 /// further optimizations.
@@ -62,13 +62,32 @@ pub unsafe fn unreachable_unchecked() -> ! {
 #[inline]
 #[unstable(feature = "renamed_spin_loop", issue = "55002")]
 pub fn spin_loop() {
-    #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
-    unsafe {
-        asm!("pause" ::: "memory" : "volatile");
+    #[cfg(
+        all(
+            any(target_arch = "x86", target_arch = "x86_64"),
+            target_feature = "sse2"
+        )
+    )] {
+        #[cfg(target_arch = "x86")] {
+            unsafe { arch::x86::_mm_pause() };
+        }
+
+        #[cfg(target_arch = "x86_64")] {
+            unsafe { arch::x86_64::_mm_pause() };
+        }
     }
 
-    #[cfg(target_arch = "aarch64")]
-    unsafe {
-        asm!("yield" ::: "memory" : "volatile");
+    #[cfg(
+        any(
+            target_arch = "aarch64",
+            all(target_arch = "arm", target_feature = "v6")
+        )
+    )] {
+        #[cfg(target_arch = "aarch64")] {
+            unsafe { arch::aarch64::__yield() };
+        }
+        #[cfg(target_arch = "arm")] {
+            unsafe { arch::arm::__yield() };
+        }
     }
 }

src/librustc/hir/check_attr.rs

@@ -177,16 +177,8 @@ impl<'a, 'tcx> CheckAttrVisitor<'a, 'tcx> {
         let mut is_transparent = false;
 
         for hint in &hints {
-            let name = if let Some(name) = hint.ident_str() {
-                name
-            } else {
-                // Invalid repr hint like repr(42). We don't check for unrecognized hints here
-                // (libsyntax does that), so just ignore it.
-                continue;
-            };
-
-            let (article, allowed_targets) = match name {
-                "C" | "align" => {
+            let (article, allowed_targets) = match hint.name_or_empty().get() {
+                name @ "C" | name @ "align" => {
                     is_c |= name == "C";
                     if target != Target::Struct &&
                             target != Target::Union &&

src/librustc/hir/lowering.rs

@@ -2672,7 +2672,7 @@ impl<'a> LoweringContext<'a> {
 
     fn lower_variant_data(&mut self, vdata: &VariantData) -> hir::VariantData {
         match *vdata {
-            VariantData::Struct(ref fields, id) => {
+            VariantData::Struct(ref fields, id, recovered) => {
                 let LoweredNodeId { node_id: _, hir_id } = self.lower_node_id(id);
 
                 hir::VariantData::Struct(
@@ -2682,6 +2682,7 @@ impl<'a> LoweringContext<'a> {
                         .map(|f| self.lower_struct_field(f))
                         .collect(),
                     hir_id,
+                    recovered,
                 )
             },
             VariantData::Tuple(ref fields, id) => {

src/librustc/hir/mod.rs

@@ -2173,7 +2173,7 @@ impl StructField {
 /// Id of the whole struct lives in `Item`.
 #[derive(Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
 pub enum VariantData {
-    Struct(HirVec<StructField>, HirId),
+    Struct(HirVec<StructField>, HirId, /* recovered */ bool),
     Tuple(HirVec<StructField>, HirId),
     Unit(HirId),
 }
@@ -2187,7 +2187,7 @@ impl VariantData {
     }
     pub fn hir_id(&self) -> HirId {
         match *self {
-            VariantData::Struct(_, hir_id)
+            VariantData::Struct(_, hir_id, _)
             | VariantData::Tuple(_, hir_id)
             | VariantData::Unit(hir_id) => hir_id,
         }

src/librustc/lint/levels.rs

@@ -194,7 +194,7 @@ impl<'a> LintLevelsBuilder<'a> {
             struct_span_err!(sess, span, E0452, "malformed lint attribute")
         };
         for attr in attrs {
-            let level = match attr.ident_str().and_then(|name| Level::from_str(name)) {
+            let level = match Level::from_str(&attr.name_or_empty()) {
                 None => continue,
                 Some(lvl) => lvl,
             };

src/librustc/lint/mod.rs

@@ -723,12 +723,7 @@ pub fn struct_lint_level<'a>(sess: &'a Session,
 
 pub fn maybe_lint_level_root(tcx: TyCtxt<'_, '_, '_>, id: hir::HirId) -> bool {
     let attrs = tcx.hir().attrs_by_hir_id(id);
-    for attr in attrs {
-        if attr.ident_str().and_then(Level::from_str).is_some() {
-            return true;
-        }
-    }
-    false
+    attrs.iter().any(|attr| Level::from_str(&attr.name_or_empty()).is_some())
 }
 
 fn lint_levels<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, cnum: CrateNum)

src/librustc/middle/lib_features.rs

@@ -65,9 +65,9 @@ impl<'a, 'tcx> LibFeatureCollector<'a, 'tcx> {
                 for meta in metas {
                     if let Some(mi) = meta.meta_item() {
                         // Find the `feature = ".."` meta-item.
-                        match (mi.ident_str(), mi.value_str()) {
-                            (Some("feature"), val) => feature = val,
-                            (Some("since"), val) => since = val,
+                        match (mi.name_or_empty().get(), mi.value_str()) {
+                            ("feature", val) => feature = val,
+                            ("since", val) => since = val,
                             _ => {}
                         }
                     }

src/librustc/middle/stability.rs

@@ -194,12 +194,11 @@ impl<'a, 'tcx: 'a> Annotator<'a, 'tcx> {
         } else {
             // Emit errors for non-staged-api crates.
             for attr in attrs {
-                if let Some(tag) = attr.ident_str() {
-                    if tag == "unstable" || tag == "stable" || tag == "rustc_deprecated" {
-                        attr::mark_used(attr);
-                        self.tcx.sess.span_err(attr.span, "stability attributes may not be used \
-                                                           outside of the standard library");
-                    }
+                let name = attr.name_or_empty();
+                if ["unstable", "stable", "rustc_deprecated"].contains(&name.get()) {
+                    attr::mark_used(attr);
+                    self.tcx.sess.span_err(attr.span, "stability attributes may not be used \
+                                                        outside of the standard library");
                 }
             }
 

src/librustc/traits/on_unimplemented.rs

@@ -177,9 +177,9 @@ impl<'a, 'gcx, 'tcx> OnUnimplementedDirective {
         for command in self.subcommands.iter().chain(Some(self)).rev() {
             if let Some(ref condition) = command.condition {
                 if !attr::eval_condition(condition, &tcx.sess.parse_sess, &mut |c| {
-                    c.ident_str().map_or(false, |name| {
+                    c.ident().map_or(false, |ident| {
                         options.contains(&(
-                            name.to_string(),
+                            ident.to_string(),
                             c.value_str().map(|s| s.as_str().to_string())
                         ))
                     })

src/librustc/ty/mod.rs

@@ -1811,6 +1811,7 @@ pub struct VariantDef {
     pub fields: Vec<FieldDef>,
     pub ctor_kind: CtorKind,
     flags: VariantFlags,
+    pub recovered: bool,
 }
 
 impl<'a, 'gcx, 'tcx> VariantDef {
@@ -1829,16 +1830,17 @@ impl<'a, 'gcx, 'tcx> VariantDef {
     ///
     /// If someone speeds up attribute loading to not be a performance concern, they can
     /// remove this hack and use the constructor `DefId` everywhere.
-    pub fn new(tcx: TyCtxt<'a, 'gcx, 'tcx>,
-               did: DefId,
-               ident: Ident,
-               discr: VariantDiscr,
-               fields: Vec<FieldDef>,
-               adt_kind: AdtKind,
-               ctor_kind: CtorKind,
-               attribute_def_id: DefId)
-               -> Self
-    {
+    pub fn new(
+        tcx: TyCtxt<'a, 'gcx, 'tcx>,
+        did: DefId,
+        ident: Ident,
+        discr: VariantDiscr,
+        fields: Vec<FieldDef>,
+        adt_kind: AdtKind,
+        ctor_kind: CtorKind,
+        attribute_def_id: DefId,
+        recovered: bool,
+    ) -> Self {
         debug!("VariantDef::new({:?}, {:?}, {:?}, {:?}, {:?}, {:?}, {:?})", did, ident, discr,
                fields, adt_kind, ctor_kind, attribute_def_id);
         let mut flags = VariantFlags::NO_VARIANT_FLAGS;
@@ -1852,7 +1854,8 @@ impl<'a, 'gcx, 'tcx> VariantDef {
             discr,
             fields,
             ctor_kind,
-            flags
+            flags,
+            recovered,
         }
     }
 
@@ -1868,7 +1871,8 @@ impl_stable_hash_for!(struct VariantDef {
     discr,
     fields,
     ctor_kind,
-    flags
+    flags,
+    recovered
 });
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq, RustcEncodable, RustcDecodable, HashStable)]

src/librustc_driver/pretty.rs

@@ -633,10 +633,20 @@ fn print_flowgraph<'a, 'tcx, W: Write>(variants: Vec<borrowck_dot::Variant>,
     let body = tcx.hir().body(body_id);
     let cfg = cfg::CFG::new(tcx, &body);
     let labelled_edges = mode != PpFlowGraphMode::UnlabelledEdges;
+    let hir_id = code.id();
+    // We have to disassemble the hir_id because name must be ASCII
+    // alphanumeric. This does not appear in the rendered graph, so it does not
+    // have to be user friendly.
+    let name = format!(
+        "hir_id_{}_{}_{}",
+        hir_id.owner.address_space().index(),
+        hir_id.owner.as_array_index(),
+        hir_id.local_id.index(),
+    );
     let lcfg = LabelledCFG {
         tcx,
         cfg: &cfg,
-        name: format!("node_{}", code.id()),
+        name,
         labelled_edges,
     };
 

src/librustc_incremental/persist/dirty_clean.rs

@@ -576,8 +576,8 @@ fn expect_associated_value(tcx: TyCtxt<'_, '_, '_>, item: &NestedMetaItem) -> as
     if let Some(value) = item.value_str() {
         value
     } else {
-        let msg = if let Some(name) = item.ident_str() {
-            format!("associated value expected for `{}`", name)
+        let msg = if let Some(ident) = item.ident() {
+            format!("associated value expected for `{}`", ident)
         } else {
             "expected an associated value".to_string()
         };

src/librustc_lint/builtin.rs

@@ -759,8 +759,9 @@ impl LintPass for DeprecatedAttr {
 
 impl EarlyLintPass for DeprecatedAttr {
     fn check_attribute(&mut self, cx: &EarlyContext<'_>, attr: &ast::Attribute) {
+        let name = attr.name_or_empty();
         for &&(n, _, _, ref g) in &self.depr_attrs {
-            if attr.ident_str() == Some(n) {
+            if name == n {
                 if let &AttributeGate::Gated(Stability::Deprecated(link, suggestion),
                                              ref name,
                                              ref reason,