Auto merge of #52735 - Mark-Simulacrum:rollup, r=Mark-Simulacrum

Rollup of 16 pull requests

Successful merges:

 - #52558 (Add tests for ICEs which no longer repro)
 - #52610 (Clarify what a task is)
 - #52617 (Don't match on region kinds when reporting NLL errors)
 - #52635 (Fix #[linkage] propagation though generic functions)
 - #52647 (Suggest to take and ignore args while closure args count mismatching)
 - #52649 (Point spans to inner elements of format strings)
 - #52654 (Format linker args in a way that works for gcc and ld)
 - #52667 (update the stdsimd submodule)
 - #52674 (Impl Executor for Box<E: Executor>)
 - #52690 (ARM: expose `rclass` and `dsp` target features)
 - #52692 (Improve readability in a few sorts)
 - #52695 (Hide some lints which are not quite right the way they are reported to the user)
 - #52718 (State default capacity for BufReader/BufWriter)
 - #52721 (std::ops::Try impl for std::task::Poll)
 - #52723 (rustc: Register crates under their real names)
 - #52734 (sparc ABI issue - structure returning from function is returned in 64bit registers (with tests))

Failed merges:

 - #52678 ([NLL] Use better spans in some errors)

r? @ghost

src/liballoc/boxed.rs

@@ -67,7 +67,7 @@ use core::marker::{Unpin, Unsize};
 use core::mem::{self, PinMut};
 use core::ops::{CoerceUnsized, Deref, DerefMut, Generator, GeneratorState};
 use core::ptr::{self, NonNull, Unique};
-use core::task::{Context, Poll};
+use core::task::{Context, Poll, Executor, SpawnErrorKind, SpawnObjError};
 
 use raw_vec::RawVec;
 use str::from_boxed_utf8_unchecked;
@@ -972,6 +972,19 @@ unsafe impl<'a, T, F> UnsafeFutureObj<'a, T> for PinBox<F>
     }
 }
 
+#[unstable(feature = "futures_api", issue = "50547")]
+impl<E> Executor for Box<E>
+    where E: Executor + ?Sized
+{
+    fn spawn_obj(&mut self, task: FutureObj<'static, ()>) -> Result<(), SpawnObjError> {
+        (**self).spawn_obj(task)
+    }
+
+    fn status(&self) -> Result<(), SpawnErrorKind> {
+        (**self).status()
+    }
+}
+
 #[unstable(feature = "futures_api", issue = "50547")]
 impl<'a, F: Future<Output = ()> + Send + 'a> From<PinBox<F>> for FutureObj<'a, ()> {
     fn from(boxed: PinBox<F>) -> Self {

src/libcore/task/executor.rs

@@ -17,21 +17,27 @@ use future::{FutureObj, LocalFutureObj};
 
 /// A task executor.
 ///
-/// A *task* is a `()`-producing async value that runs at the top level, and will
-/// be `poll`ed until completion. It's also the unit at which wake-up
-/// notifications occur. Executors, such as thread pools, allow tasks to be
-/// spawned and are responsible for putting tasks onto ready queues when
-/// they are woken up, and polling them when they are ready.
+/// Futures are polled until completion by tasks, a kind of lightweight
+/// "thread". A *task executor* is responsible for the creation of these tasks
+/// and the coordination of their execution on real operating system threads. In
+/// particular, whenever a task signals that it can make further progress via a
+/// wake-up notification, it is the responsibility of the task executor to put
+/// the task into a queue to continue executing it, i.e. polling the future in
+/// it, later.
 pub trait Executor {
-    /// Spawn the given task, polling it until completion.
+    /// Spawns a new task with the given future. The future will be polled until
+    /// completion.
     ///
     /// # Errors
     ///
     /// The executor may be unable to spawn tasks, either because it has
     /// been shut down or is resource-constrained.
-    fn spawn_obj(&mut self, task: FutureObj<'static, ()>) -> Result<(), SpawnObjError>;
+    fn spawn_obj(
+        &mut self,
+        future: FutureObj<'static, ()>,
+    ) -> Result<(), SpawnObjError>;
 
-    /// Determine whether the executor is able to spawn new tasks.
+    /// Determines whether the executor is able to spawn new tasks.
     ///
     /// # Returns
     ///
@@ -75,8 +81,8 @@ pub struct SpawnObjError {
     /// The kind of error
     pub kind: SpawnErrorKind,
 
-    /// The task for which spawning was attempted
-    pub task: FutureObj<'static, ()>,
+    /// The future for which spawning inside a task was attempted
+    pub future: FutureObj<'static, ()>,
 }
 
 /// The result of a failed spawn
@@ -85,6 +91,6 @@ pub struct SpawnLocalObjError {
     /// The kind of error
     pub kind: SpawnErrorKind,
 
-    /// The task for which spawning was attempted
-    pub task: LocalFutureObj<'static, ()>,
+    /// The future for which spawning inside a task was attempted
+    pub future: LocalFutureObj<'static, ()>,
 }

src/libcore/task/poll.rs

@@ -12,6 +12,9 @@
             reason = "futures in libcore are unstable",
             issue = "50547")]
 
+use ops::Try;
+use result::Result;
+
 /// Indicates whether a value is available or if the current task has been
 /// scheduled to receive a wakeup instead.
 #[derive(Copy, Clone, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
@@ -39,6 +42,7 @@ impl<T> Poll<T> {
     }
 
     /// Returns whether this is `Poll::Ready`
+    #[inline]
     pub fn is_ready(&self) -> bool {
         match *self {
             Poll::Ready(_) => true,
@@ -47,6 +51,7 @@ impl<T> Poll<T> {
     }
 
     /// Returns whether this is `Poll::Pending`
+    #[inline]
     pub fn is_pending(&self) -> bool {
         !self.is_ready()
     }
@@ -81,3 +86,52 @@ impl<T> From<T> for Poll<T> {
         Poll::Ready(t)
     }
 }
+
+impl<T, E> Try for Poll<Result<T, E>> {
+    type Ok = Poll<T>;
+    type Error = E;
+
+    #[inline]
+    fn into_result(self) -> Result<Self::Ok, Self::Error> {
+        match self {
+            Poll::Ready(Ok(x)) => Ok(Poll::Ready(x)),
+            Poll::Ready(Err(e)) => Err(e),
+            Poll::Pending => Ok(Poll::Pending),
+        }
+    }
+
+    #[inline]
+    fn from_error(e: Self::Error) -> Self {
+        Poll::Ready(Err(e))
+    }
+
+    #[inline]
+    fn from_ok(x: Self::Ok) -> Self {
+        x.map(Ok)
+    }
+}
+
+impl<T, E> Try for Poll<Option<Result<T, E>>> {
+    type Ok = Poll<Option<T>>;
+    type Error = E;
+
+    #[inline]
+    fn into_result(self) -> Result<Self::Ok, Self::Error> {
+        match self {
+            Poll::Ready(Some(Ok(x))) => Ok(Poll::Ready(Some(x))),
+            Poll::Ready(Some(Err(e))) => Err(e),
+            Poll::Ready(None) => Ok(Poll::Ready(None)),
+            Poll::Pending => Ok(Poll::Pending),
+        }
+    }
+
+    #[inline]
+    fn from_error(e: Self::Error) -> Self {
+        Poll::Ready(Some(Err(e)))
+    }
+
+    #[inline]
+    fn from_ok(x: Self::Ok) -> Self {
+        x.map(|x| x.map(Ok))
+    }
+}

src/libfmt_macros/lib.rs

@@ -154,6 +154,8 @@ pub struct Parser<'a> {
     style: Option<usize>,
     /// How many newlines have been seen in the string so far, to adjust the error spans
     seen_newlines: usize,
+    /// Start and end byte offset of every successfuly parsed argument
+    pub arg_places: Vec<(usize, usize)>,
 }
 
 impl<'a> Iterator for Parser<'a> {
@@ -168,9 +170,13 @@ impl<'a> Iterator for Parser<'a> {
                     if self.consume('{') {
                         Some(String(self.string(pos + 1)))
                     } else {
-                        let ret = Some(NextArgument(self.argument()));
-                        self.must_consume('}');
-                        ret
+                        let mut arg = self.argument();
+                        if let Some(arg_pos) = self.must_consume('}').map(|end| {
+                            (pos + raw + 1, end + raw + 2)
+                        }) {
+                            self.arg_places.push(arg_pos);
+                        }
+                        Some(NextArgument(arg))
                     }
                 }
                 '}' => {
@@ -211,6 +217,7 @@ impl<'a> Parser<'a> {
             curarg: 0,
             style,
             seen_newlines: 0,
+            arg_places: vec![],
         }
     }
 
@@ -271,20 +278,22 @@ impl<'a> Parser<'a> {
 
     /// Forces consumption of the specified character. If the character is not
     /// found, an error is emitted.
-    fn must_consume(&mut self, c: char) {
+    fn must_consume(&mut self, c: char) -> Option<usize> {
         self.ws();
         let raw = self.style.unwrap_or(0);
 
         let padding = raw + self.seen_newlines;
         if let Some(&(pos, maybe)) = self.cur.peek() {
             if c == maybe {
                 self.cur.next();
+                Some(pos)
             } else {
                 let pos = pos + padding + 1;
                 self.err(format!("expected `{:?}`, found `{:?}`", c, maybe),
                          format!("expected `{}`", c),
                          pos,
                          pos);
+                None
             }
         } else {
             let msg = format!("expected `{:?}` but string was terminated", c);
@@ -302,6 +311,7 @@ impl<'a> Parser<'a> {
             } else {
                 self.err(msg, format!("expected `{:?}`", c), pos, pos);
             }
+            None
         }
     }
 

src/librustc/traits/error_reporting.rs

@@ -1050,6 +1050,30 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
         if let Some(found_span) = found_span {
             err.span_label(found_span, format!("takes {}", found_str));
 
+            // Suggest to take and ignore the arguments with expected_args_length `_`s if
+            // found arguments is empty (assume the user just wants to ignore args in this case).
+            // For example, if `expected_args_length` is 2, suggest `|_, _|`.
+            if found_args.is_empty() && is_closure {
+                let mut underscores = "_".repeat(expected_args.len())
+                                      .split("")
+                                      .filter(|s| !s.is_empty())
+                                      .collect::<Vec<_>>()
+                                      .join(", ");
+                err.span_suggestion_with_applicability(
+                    found_span,
+                    &format!(
+                        "consider changing the closure to take and ignore the expected argument{}",
+                        if expected_args.len() < 2 {
+                            ""
+                        } else {
+                            "s"
+                        }
+                    ),
+                    format!("|{}|", underscores),
+                    Applicability::MachineApplicable,
+                );
+            }
+
             if let &[ArgKind::Tuple(_, ref fields)] = &found_args[..] {
                 if fields.len() == expected_args.len() {
                     let sugg = fields.iter()

src/librustc_codegen_llvm/back/linker.rs

@@ -218,24 +218,26 @@ impl<'a> GccLinker<'a> {
 }
 
 impl<'a> Linker for GccLinker<'a> {
-    fn link_dylib(&mut self, lib: &str) { self.hint_dynamic(); self.cmd.arg("-l").arg(lib); }
-    fn link_staticlib(&mut self, lib: &str) { self.hint_static(); self.cmd.arg("-l").arg(lib); }
+    fn link_dylib(&mut self, lib: &str) { self.hint_dynamic(); self.cmd.arg(format!("-l{}",lib)); }
+    fn link_staticlib(&mut self, lib: &str) {
+        self.hint_static(); self.cmd.arg(format!("-l{}",lib));
+    }
     fn link_rlib(&mut self, lib: &Path) { self.hint_static(); self.cmd.arg(lib); }
     fn include_path(&mut self, path: &Path) { self.cmd.arg("-L").arg(path); }
     fn framework_path(&mut self, path: &Path) { self.cmd.arg("-F").arg(path); }
     fn output_filename(&mut self, path: &Path) { self.cmd.arg("-o").arg(path); }
     fn add_object(&mut self, path: &Path) { self.cmd.arg(path); }
     fn position_independent_executable(&mut self) { self.cmd.arg("-pie"); }
     fn no_position_independent_executable(&mut self) { self.cmd.arg("-no-pie"); }
-    fn full_relro(&mut self) { self.linker_arg("-z,relro,-z,now"); }
-    fn partial_relro(&mut self) { self.linker_arg("-z,relro"); }
-    fn no_relro(&mut self) { self.linker_arg("-z,norelro"); }
+    fn full_relro(&mut self) { self.linker_arg("-zrelro"); self.linker_arg("-znow"); }
+    fn partial_relro(&mut self) { self.linker_arg("-zrelro"); }
+    fn no_relro(&mut self) { self.linker_arg("-znorelro"); }
     fn build_static_executable(&mut self) { self.cmd.arg("-static"); }
     fn args(&mut self, args: &[String]) { self.cmd.args(args); }
 
     fn link_rust_dylib(&mut self, lib: &str, _path: &Path) {
         self.hint_dynamic();
-        self.cmd.arg("-l").arg(lib);
+        self.cmd.arg(format!("-l{}",lib));
     }
 
     fn link_framework(&mut self, framework: &str) {
@@ -253,23 +255,22 @@ impl<'a> Linker for GccLinker<'a> {
         self.hint_static();
         let target = &self.sess.target.target;
         if !target.options.is_like_osx {
-            self.linker_arg("--whole-archive").cmd.arg("-l").arg(lib);
+            self.linker_arg("--whole-archive").cmd.arg(format!("-l{}",lib));
             self.linker_arg("--no-whole-archive");
         } else {
             // -force_load is the macOS equivalent of --whole-archive, but it
             // involves passing the full path to the library to link.
-            let mut v = OsString::from("-force_load,");
-            v.push(&archive::find_library(lib, search_path, &self.sess));
-            self.linker_arg(&v);
+            self.linker_arg("-force_load");
+            let lib = archive::find_library(lib, search_path, &self.sess);
+            self.linker_arg(&lib);
         }
     }
 
     fn link_whole_rlib(&mut self, lib: &Path) {
         self.hint_static();
         if self.sess.target.target.options.is_like_osx {
-            let mut v = OsString::from("-force_load,");
-            v.push(lib);
-            self.linker_arg(&v);
+            self.linker_arg("-force_load");
+            self.linker_arg(&lib);
         } else {
             self.linker_arg("--whole-archive").cmd.arg(lib);
             self.linker_arg("--no-whole-archive");
@@ -294,8 +295,7 @@ impl<'a> Linker for GccLinker<'a> {
         if self.sess.target.target.options.is_like_osx {
             self.linker_arg("-dead_strip");
         } else if self.sess.target.target.options.is_like_solaris {
-            self.linker_arg("-z");
-            self.linker_arg("ignore");
+            self.linker_arg("-zignore");
 
         // If we're building a dylib, we don't use --gc-sections because LLVM
         // has already done the best it can do, and we also don't want to
@@ -369,7 +369,8 @@ impl<'a> Linker for GccLinker<'a> {
             // the right `-Wl,-install_name` with an `@rpath` in it.
             if self.sess.opts.cg.rpath ||
                self.sess.opts.debugging_opts.osx_rpath_install_name {
-                let mut v = OsString::from("-install_name,@rpath/");
+                self.linker_arg("-install_name");
+                let mut v = OsString::from("@rpath/");
                 v.push(out_filename.file_name().unwrap());
                 self.linker_arg(&v);
             }
@@ -448,7 +449,8 @@ impl<'a> Linker for GccLinker<'a> {
     }
 
     fn subsystem(&mut self, subsystem: &str) {
-        self.linker_arg(&format!("--subsystem,{}", subsystem));
+        self.linker_arg("--subsystem");
+        self.linker_arg(&subsystem);
     }
 
     fn finalize(&mut self) -> Command {