Auto merge of #47740 - GuillaumeGomez:rollup, r=GuillaumeGomez

Rollup of 10 pull requests

- Successful merges: #47534, #47609, #47679, #47691, #47700, #47702, #47717, #47721, #47726, #47729
- Failed merges:

Author: bors

src/Cargo.lock

@@ -47,13 +47,6 @@ ENV \
     CC_x86_64_sun_solaris=x86_64-sun-solaris2.10-gcc \
     CXX_x86_64_sun_solaris=x86_64-sun-solaris2.10-g++
 
-# FIXME(EdSchouten): Remove this once cc ≥1.0.4 has been merged. It can
-# automatically pick the right compiler path.
-ENV \
-    AR_x86_64_unknown_cloudabi=x86_64-unknown-cloudabi-ar \
-    CC_x86_64_unknown_cloudabi=x86_64-unknown-cloudabi-clang \
-    CXX_x86_64_unknown_cloudabi=x86_64-unknown-cloudabi-clang++
-
 ENV TARGETS=x86_64-unknown-fuchsia
 ENV TARGETS=$TARGETS,aarch64-unknown-fuchsia
 ENV TARGETS=$TARGETS,sparcv9-sun-solaris

src/ci/docker/dist-various-2/Dockerfile

@@ -40,12 +40,6 @@ ln -s ../lib/llvm-5.0/bin/clang /usr/bin/${target}-c++
 ln -s ../lib/llvm-5.0/bin/lld /usr/bin/${target}-ld
 ln -s ../../${target} /usr/lib/llvm-5.0/${target}
 
-# FIXME(EdSchouten): Remove this once cc ≥1.0.4 has been merged. It
-# can make use of ${target}-cc and ${target}-c++, without incorrectly
-# assuming it's MSVC.
-ln -s ../lib/llvm-5.0/bin/clang /usr/bin/${target}-clang
-ln -s ../lib/llvm-5.0/bin/clang /usr/bin/${target}-clang++
-
 # Install the C++ runtime libraries from CloudABI Ports.
 echo deb https://nuxi.nl/distfiles/cloudabi-ports/debian/ cloudabi cloudabi > \
     /etc/apt/sources.list.d/cloudabi.list

src/ci/docker/dist-various-2/build-cloudabi-toolchain.sh

@@ -29,4 +29,4 @@ rustdoc reference.md
 An overview of how to use the `rustdoc` command is available [in the docs][1].
 Further details are available from the command line by with `rustdoc --help`.
 
-[1]: https://github.com/rust-lang/rust/blob/master/src/doc/book/documentation.md
+[1]: https://github.com/rust-lang/rust/blob/master/src/doc/rustdoc/src/what-is-rustdoc.md

src/doc/README.md

@@ -28,6 +28,7 @@ use util::nodemap::FxHashMap;
 
 use syntax::ast;
 use syntax::symbol::Symbol;
+use syntax_pos::Span;
 use hir::itemlikevisit::ItemLikeVisitor;
 use hir;
 
@@ -104,17 +105,18 @@ struct LanguageItemCollector<'a, 'tcx: 'a> {
 
 impl<'a, 'v, 'tcx> ItemLikeVisitor<'v> for LanguageItemCollector<'a, 'tcx> {
     fn visit_item(&mut self, item: &hir::Item) {
-        if let Some(value) = extract(&item.attrs) {
+        if let Some((value, span)) = extract(&item.attrs) {
             let item_index = self.item_refs.get(&*value.as_str()).cloned();
 
             if let Some(item_index) = item_index {
                 let def_id = self.tcx.hir.local_def_id(item.id);
                 self.collect_item(item_index, def_id);
             } else {
-                let span = self.tcx.hir.span(item.id);
-                span_err!(self.tcx.sess, span, E0522,
-                          "definition of an unknown language item: `{}`.",
-                          value);
+                let mut err = struct_span_err!(self.tcx.sess, span, E0522,
+                                               "definition of an unknown language item: `{}`",
+                                               value);
+                err.span_label(span, format!("definition of unknown language item `{}`", value));
+                err.emit();
             }
         }
     }
@@ -177,11 +179,11 @@ impl<'a, 'tcx> LanguageItemCollector<'a, 'tcx> {
     }
 }
 
-pub fn extract(attrs: &[ast::Attribute]) -> Option<Symbol> {
+pub fn extract(attrs: &[ast::Attribute]) -> Option<(Symbol, Span)> {
     for attribute in attrs {
         if attribute.check_name("lang") {
             if let Some(value) = attribute.value_str() {
-                return Some(value)
+                return Some((value, attribute.span));
             }
         }
     }

src/librustc/middle/lang_items.rs

@@ -55,7 +55,7 @@ pub fn check_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 }
 
 pub fn link_name(attrs: &[ast::Attribute]) -> Option<Symbol> {
-    lang_items::extract(attrs).and_then(|name| {
+    lang_items::extract(attrs).and_then(|(name, _)| {
         $(if name == stringify!($name) {
             Some(Symbol::intern(stringify!($sym)))
         } else)* {
@@ -129,7 +129,7 @@ impl<'a, 'tcx, 'v> Visitor<'v> for Context<'a, 'tcx> {
     }
 
     fn visit_foreign_item(&mut self, i: &hir::ForeignItem) {
-        if let Some(lang_item) = lang_items::extract(&i.attrs) {
+        if let Some((lang_item, _)) = lang_items::extract(&i.attrs) {
             self.register(&lang_item.as_str(), i.span);
         }
         intravisit::walk_foreign_item(self, i)

src/librustc/middle/weak_lang_items.rs

@@ -1273,14 +1273,6 @@ pub fn monitor<F: FnOnce() + Send + 'static>(f: F) {
                              &note,
                              errors::Level::Note);
             }
-            if match env::var_os("RUST_BACKTRACE") {
-                Some(val) => &val != "0",
-                None => false,
-            } {
-                handler.emit(&MultiSpan::new(),
-                             "run with `RUST_BACKTRACE=1` for a backtrace",
-                             errors::Level::Note);
-            }
 
             eprintln!("{}", str::from_utf8(&data.lock().unwrap()).unwrap());
         }

src/librustc_driver/lib.rs

@@ -102,11 +102,18 @@ impl<'a, 'b> Visitor<'a> for UnusedImportCheckVisitor<'a, 'b> {
         }
 
         if let ast::UseTreeKind::Nested(ref items) = use_tree.kind {
+            // If it's the parent group, cover the entire use item
+            let span = if nested {
+                use_tree.span
+            } else {
+                self.item_span
+            };
+
             if items.len() == 0 {
                 self.unused_imports
                     .entry(self.base_id)
                     .or_insert_with(NodeMap)
-                    .insert(id, self.item_span);
+                    .insert(id, span);
             }
         } else {
             let base_id = self.base_id;

src/librustc_resolve/check_unused.rs

@@ -15,7 +15,7 @@ use rustc::infer::InferOk;
 use rustc::traits::ObligationCause;
 
 use syntax::ast;
-use syntax::util::parser::AssocOp;
+use syntax::util::parser::PREC_POSTFIX;
 use syntax_pos::{self, Span};
 use rustc::hir;
 use rustc::hir::print;
@@ -336,7 +336,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
         // For now, don't suggest casting with `as`.
         let can_cast = false;
 
-        let needs_paren = expr.precedence().order() < (AssocOp::As.precedence() as i8);
+        let needs_paren = expr.precedence().order() < (PREC_POSTFIX as i8);
 
         if let Ok(src) = self.tcx.sess.codemap().span_to_snippet(expr.span) {
             let msg = format!("you can cast an `{}` to `{}`", checked_ty, expected_ty);

src/librustc_typeck/check/demand.rs

@@ -513,8 +513,13 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                 // this isn't perfect (that is, there are cases when
                 // implementing a trait would be legal but is rejected
                 // here).
-                (type_is_local || info.def_id.is_local())
-                    && self.associated_item(info.def_id, item_name, Namespace::Value).is_some()
+                (type_is_local || info.def_id.is_local()) &&
+                    self.associated_item(info.def_id, item_name, Namespace::Value)
+                        .filter(|item| {
+                            // We only want to suggest public or local traits (#45781).
+                            item.vis == ty::Visibility::Public || info.def_id.is_local()
+                        })
+                        .is_some()
             })
             .collect::<Vec<_>>();