Rollup of 18 pull requests

Cargo.lock

@@ -81,7 +81,7 @@ dependencies = [
 
 [[package]]
 name = "backtrace"
-version = "0.3.9"
+version = "0.3.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "backtrace-sys 0.1.24 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -614,7 +614,7 @@ dependencies = [
 
 [[package]]
 name = "datafrog"
-version = "0.1.0"
+version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -728,15 +728,15 @@ name = "error-chain"
 version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "backtrace 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "backtrace 0.3.11 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "error-chain"
 version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "backtrace 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "backtrace 0.3.11 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -751,7 +751,7 @@ name = "failure"
 version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "backtrace 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "backtrace 0.3.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "failure_derive 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1625,10 +1625,10 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "polonius-engine"
-version = "0.5.0"
+version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "datafrog 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "datafrog 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-hash 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -2060,7 +2060,7 @@ name = "rustc"
 version = "0.0.0"
 dependencies = [
  "arena 0.0.0",
- "backtrace 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "backtrace 0.3.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "chalk-engine 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2071,7 +2071,7 @@ dependencies = [
  "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "polonius-engine 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "polonius-engine 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-rayon 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-rayon-core 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_apfloat 0.0.0",
@@ -2518,7 +2518,7 @@ dependencies = [
  "graphviz 0.0.0",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "log_settings 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "polonius-engine 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "polonius-engine 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc 0.0.0",
  "rustc_apfloat 0.0.0",
  "rustc_data_structures 0.0.0",
@@ -3380,7 +3380,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum arrayvec 0.4.7 (registry+https://github.com/rust-lang/crates.io-index)" = "a1e964f9e24d588183fcb43503abda40d288c8657dfc27311516ce2f05675aef"
 "checksum assert_cli 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "98589b0e465a6c510d95fceebd365bb79bedece7f6e18a480897f2015f85ec51"
 "checksum atty 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "9a7d5b8723950951411ee34d271d99dddcc2035a16ab25310ea2c8cfd4369652"
-"checksum backtrace 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)" = "89a47830402e9981c5c41223151efcced65a0510c13097c769cede7efb34782a"
+"checksum backtrace 0.3.11 (registry+https://github.com/rust-lang/crates.io-index)" = "18b65ea1161bfb2dd6da6fade5edd4dbd08fba85012123dd333d2fd1b90b2782"
 "checksum backtrace-sys 0.1.24 (registry+https://github.com/rust-lang/crates.io-index)" = "c66d56ac8dabd07f6aacdaf633f4b8262f5b3601a810a0dcddffd5c22c69daa0"
 "checksum bit-set 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "6f1efcc46c18245a69c38fcc5cc650f16d3a59d034f3106e9ed63748f695730a"
 "checksum bit-vec 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "4440d5cb623bb7390ae27fec0bb6c61111969860f8e3ae198bfa0663645e67cf"
@@ -3419,7 +3419,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum crypto-hash 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "09de9ee0fc255ace04c7fa0763c9395a945c37c8292bb554f8d48361d1dcf1b4"
 "checksum curl 0.4.19 (registry+https://github.com/rust-lang/crates.io-index)" = "c7c9d851c825e0c033979d4516c9173bc19a78a96eb4d6ae51d4045440eafa16"
 "checksum curl-sys 0.4.15 (registry+https://github.com/rust-lang/crates.io-index)" = "721c204978be2143fab0a84b708c49d79d1f6100b8785610f456043a90708870"
-"checksum datafrog 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "16d724bf4ffe77cdceeecd461009b5f8d9e23c5d645d68bedb4586bf43e7e142"
+"checksum datafrog 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "71a3eacc779bb35090718501c2de27bb679dee18f6c28e6589590e4ed8b9fa08"
 "checksum derive-new 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)" = "6ca414e896ae072546f4d789f452daaecf60ddee4c9df5dc6d5936d769e3d87c"
 "checksum derive_more 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3f57d78cf3bd45270dad4e70c21ec77a960b36c7a841ff9db76aaa775a8fb871"
 "checksum diff 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)" = "3c2b69f912779fbb121ceb775d74d51e915af17aaebc38d28a592843a2dd0a3a"
@@ -3529,7 +3529,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum phf_generator 0.7.22 (registry+https://github.com/rust-lang/crates.io-index)" = "05a079dd052e7b674d21cb31cbb6c05efd56a2cd2827db7692e2f1a507ebd998"
 "checksum phf_shared 0.7.22 (registry+https://github.com/rust-lang/crates.io-index)" = "c2261d544c2bb6aa3b10022b0be371b9c7c64f762ef28c6f5d4f1ef6d97b5930"
 "checksum pkg-config 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)" = "676e8eb2b1b4c9043511a9b7bea0915320d7e502b0a079fb03f9635a5252b18c"
-"checksum polonius-engine 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a5b6b0a7f5f4278b991ffd14abce1d01b013121ad297460237ef0a2f08d43201"
+"checksum polonius-engine 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d9274a1db7bffb87f7e810ef480a75b67eed0f1a3838f80c652e881f4b4970fd"
 "checksum precomputed-hash 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "925383efa346730478fb4838dbe9137d2a47675ad789c546d150a6e1dd4ab31c"
 "checksum pretty_assertions 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3a029430f0d744bc3d15dd474d591bed2402b645d024583082b9f63bb936dac6"
 "checksum pretty_env_logger 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "df8b3f4e0475def7d9c2e5de8e5a1306949849761e107b360d03e98eafaffd61"

README.md

@@ -10,7 +10,7 @@ standard library, and documentation.
 
 Read ["Installation"] from [The Book].
 
-["Installation"]: https://doc.rust-lang.org/book/second-edition/ch01-01-installation.html
+["Installation"]: https://doc.rust-lang.org/book/ch01-01-installation.html
 [The Book]: https://doc.rust-lang.org/book/index.html
 
 ## Building from Source

src/ci/docker/dist-various-1/Dockerfile

@@ -52,8 +52,8 @@ RUN env \
     CXX=arm-linux-gnueabi-g++ CXXFLAGS="-march=armv6 -marm" \
     bash musl.sh arm && \
     env \
-    CC=arm-linux-gnueabihf-gcc CFLAGS="-march=armv6 -marm" \
-    CXX=arm-linux-gnueabihf-g++ CXXFLAGS="-march=armv6 -marm" \
+    CC=arm-linux-gnueabihf-gcc CFLAGS="-march=armv6 -marm -mfpu=vfp" \
+    CXX=arm-linux-gnueabihf-g++ CXXFLAGS="-march=armv6 -marm -mfpu=vfp" \
     bash musl.sh armhf && \
     env \
     CC=arm-linux-gnueabihf-gcc CFLAGS="-march=armv7-a" \

src/liballoc/collections/linked_list.rs

@@ -627,7 +627,9 @@ impl<T> LinkedList<T> {
         self.pop_front_node().map(Node::into_element)
     }
 
-    /// Appends an element to the back of a list
+    /// Appends an element to the back of a list.
+    ///
+    /// This operation should compute in O(1) time.
     ///
     /// # Examples
     ///
@@ -647,6 +649,8 @@ impl<T> LinkedList<T> {
     /// Removes the last element from a list and returns it, or `None` if
     /// it is empty.
     ///
+    /// This operation should compute in O(1) time.
+    ///
     /// # Examples
     ///
     /// ```

src/liballoc/tests/vec.rs

@@ -79,6 +79,11 @@ fn test_reserve() {
     assert!(v.capacity() >= 33)
 }
 
+#[test]
+fn test_zst_capacity() {
+    assert_eq!(Vec::<()>::new().capacity(), usize::max_value());
+}
+
 #[test]
 fn test_extend() {
     let mut v = Vec::new();

src/libcore/future/future.rs

@@ -33,6 +33,7 @@ use task::{Poll, LocalWaker};
 ///
 /// When using a future, you generally won't call `poll` directly, but instead
 /// `await!` the value.
+#[must_use]
 pub trait Future {
     /// The result of the `Future`.
     type Output;

src/libcore/iter/iterator.rs

@@ -98,6 +98,7 @@ fn _assert_is_object_safe(_: &dyn Iterator<Item=()>) {}
     message="`{Self}` is not an iterator"
 )]
 #[doc(spotlight)]
+#[must_use]
 pub trait Iterator {
     /// The type of the elements being iterated over.
     #[stable(feature = "rust1", since = "1.0.0")]

src/libcore/ops/function.rs

@@ -72,6 +72,7 @@
     label="expected an `Fn<{Args}>` closure, found `{Self}`",
 )]
 #[fundamental] // so that regex can rely that `&str: !FnMut`
+#[must_use]
 pub trait Fn<Args> : FnMut<Args> {
     /// Performs the call operation.
     #[unstable(feature = "fn_traits", issue = "29625")]
@@ -150,6 +151,7 @@ pub trait Fn<Args> : FnMut<Args> {
     label="expected an `FnMut<{Args}>` closure, found `{Self}`",
 )]
 #[fundamental] // so that regex can rely that `&str: !FnMut`
+#[must_use]
 pub trait FnMut<Args> : FnOnce<Args> {
     /// Performs the call operation.
     #[unstable(feature = "fn_traits", issue = "29625")]
@@ -228,6 +230,7 @@ pub trait FnMut<Args> : FnOnce<Args> {
     label="expected an `FnOnce<{Args}>` closure, found `{Self}`",
 )]
 #[fundamental] // so that regex can rely that `&str: !FnMut`
+#[must_use]
 pub trait FnOnce<Args> {
     /// The returned type after the call operator is used.
     #[stable(feature = "fn_once_output", since = "1.12.0")]

src/librustc/Cargo.toml

@@ -17,7 +17,7 @@ jobserver = "0.1"
 lazy_static = "1.0.0"
 scoped-tls = { version = "0.1.1", features = ["nightly"] }
 log = { version = "0.4", features = ["release_max_level_info", "std"] }
-polonius-engine = "0.5.0"
+polonius-engine = "0.6.1"
 rustc-rayon = "0.1.1"
 rustc-rayon-core = "0.1.1"
 rustc_apfloat = { path = "../librustc_apfloat" }

src/librustc/infer/error_reporting/mod.rs

@@ -1095,15 +1095,16 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
                             let sp = hir.span(id);
                             // `sp` only covers `T`, change it so that it covers
                             // `T:` when appropriate
-                            let sp = if has_bounds {
+                            let is_impl_trait = bound_kind.to_string().starts_with("impl ");
+                            let sp = if has_bounds && !is_impl_trait {
                                 sp.to(self.tcx
                                     .sess
                                     .source_map()
                                     .next_point(self.tcx.sess.source_map().next_point(sp)))
                             } else {
                                 sp
                             };
-                            (sp, has_bounds)
+                            (sp, has_bounds, is_impl_trait)
                         })
                     } else {
                         None
@@ -1136,25 +1137,33 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
 
         fn binding_suggestion<'tcx, S: fmt::Display>(
             err: &mut DiagnosticBuilder<'tcx>,
-            type_param_span: Option<(Span, bool)>,
+            type_param_span: Option<(Span, bool, bool)>,
             bound_kind: GenericKind<'tcx>,
             sub: S,
         ) {
-            let consider = &format!(
-                "consider adding an explicit lifetime bound `{}: {}`...",
-                bound_kind, sub
+            let consider = format!(
+                "consider adding an explicit lifetime bound {}",
+                if type_param_span.map(|(_, _, is_impl_trait)| is_impl_trait).unwrap_or(false) {
+                    format!(" `{}` to `{}`...", sub, bound_kind)
+                } else {
+                    format!("`{}: {}`...", bound_kind, sub)
+                },
             );
-            if let Some((sp, has_lifetimes)) = type_param_span {
-                let tail = if has_lifetimes { " + " } else { "" };
-                let suggestion = format!("{}: {}{}", bound_kind, sub, tail);
+            if let Some((sp, has_lifetimes, is_impl_trait)) = type_param_span {
+                let suggestion = if is_impl_trait {
+                    format!("{} + {}", bound_kind, sub)
+                } else {
+                    let tail = if has_lifetimes { " + " } else { "" };
+                    format!("{}: {}{}", bound_kind, sub, tail)
+                };
                 err.span_suggestion_short_with_applicability(
                     sp,
-                    consider,
+                    &consider,
                     suggestion,
                     Applicability::MaybeIncorrect, // Issue #41966
                 );
             } else {
-                err.help(consider);
+                err.help(&consider);
             }
         }
 

src/librustc/lint/builtin.rs

@@ -365,6 +365,13 @@ pub mod parser {
     }
 }
 
+declare_lint! {
+    pub DEPRECATED_IN_FUTURE,
+    Allow,
+    "detects use of items that will be deprecated in a future version",
+    report_in_external_macro: true
+}
+
 /// Does nothing as a lint pass, but registers some `Lint`s
 /// that are used by other parts of the compiler.
 #[derive(Copy, Clone)]
@@ -427,6 +434,7 @@ impl LintPass for HardwiredLints {
             MACRO_USE_EXTERN_CRATE,
             MACRO_EXPANDED_MACRO_EXPORTS_ACCESSED_BY_ABSOLUTE_PATHS,
             parser::QUESTION_MARK_MACRO_SEP,
+            DEPRECATED_IN_FUTURE,
         )
     }
 }

src/librustc/middle/liveness.rs

@@ -1657,11 +1657,15 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
     fn report_dead_assign(&self, hir_id: HirId, sp: Span, var: Variable, is_argument: bool) {
         if let Some(name) = self.should_warn(var) {
             if is_argument {
-                self.ir.tcx.lint_hir(lint::builtin::UNUSED_ASSIGNMENTS, hir_id, sp,
-                    &format!("value passed to `{}` is never read", name));
+                self.ir.tcx.struct_span_lint_hir(lint::builtin::UNUSED_ASSIGNMENTS, hir_id, sp,
+                &format!("value passed to `{}` is never read", name))
+                .help("maybe it is overwritten before being read?")
+                .emit();
             } else {
-                self.ir.tcx.lint_hir(lint::builtin::UNUSED_ASSIGNMENTS, hir_id, sp,
-                    &format!("value assigned to `{}` is never read", name));
+                self.ir.tcx.struct_span_lint_hir(lint::builtin::UNUSED_ASSIGNMENTS, hir_id, sp,
+                &format!("value assigned to `{}` is never read", name))
+                .help("maybe it is overwritten before being read?")
+                .emit();
             }
         }
     }