---

yaml
---
r: 218207
b: refs/heads/master
c: 6c52903
h: refs/heads/master
i:
  218205: 90d6d6a
  218203: b2eec32
  218199: 474e64d
  218191: fc4706e
  218175: 54e5645
v: v3

Author: steveklabnik

[refs]

@@ -1,5 +1,5 @@
 ---
-refs/heads/master: d5629e9e3556a35e2a9bc2f5bd1bee30d7966e0d
+refs/heads/master: 6c5290389170cc024e1ecfb09efdd88ae0303d02
 refs/heads/snap-stage3: ba0e1cd8147d452c356aacb29fb87568ca26f111
 refs/heads/try: b53c0f93eedcdedd4fd89bccc5a3a09d1c5cd23e
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105

trunk/src/doc/complement-design-faq.md

@@ -99,7 +99,7 @@ Second, it makes cost explicit. In general, the only safe way to have a
 non-exhaustive match would be to panic the thread if nothing is matched, though
 it could fall through if the type of the `match` expression is `()`. This sort
 of hidden cost and special casing is against the language's philosophy. It's
-easy to ignore all unspecified cases by using the `_` wildcard:
+easy to ignore certain cases by using the `_` wildcard:
 
 ```rust,ignore
 match val.do_something() {

trunk/src/doc/trpl/concurrency.md

@@ -10,12 +10,11 @@ system is up to the task, and gives you powerful ways to reason about
 concurrent code at compile time.
 
 Before we talk about the concurrency features that come with Rust, it's important
-to understand something: Rust is low-level enough that the vast majority of
-this is provided by the standard library, not by the language. This means that
-if you don't like some aspect of the way Rust handles concurrency, you can
-implement an alternative way of doing things.
-[mio](https://github.com/carllerche/mio) is a real-world example of this
-principle in action.
+to understand something: Rust is low-level enough that all of this is provided
+by the standard library, not by the language. This means that if you don't like
+some aspect of the way Rust handles concurrency, you can implement an alternative
+way of doing things. [mio](https://github.com/carllerche/mio) is a real-world
+example of this principle in action.
 
 ## Background: `Send` and `Sync`
 

trunk/src/doc/trpl/lifetimes.md

@@ -101,8 +101,6 @@ the lifetime `'a` has snuck in between the `&` and the `mut i32`. We read `&mut
 i32` as ‘a mutable reference to an i32’ and `&'a mut i32` as ‘a mutable
 reference to an `i32` with the lifetime `'a`’.
 
-# In `struct`s
-
 You’ll also need explicit lifetimes when working with [`struct`][structs]s:
 
 ```rust
@@ -139,33 +137,6 @@ x: &'a i32,
 uses it. So why do we need a lifetime here? We need to ensure that any reference
 to a `Foo` cannot outlive the reference to an `i32` it contains.
 
-## `impl` blocks
-
-Let’s implement a method on `Foo`:
-
-```rust
-struct Foo<'a> {
-    x: &'a i32,
-}
-
-impl<'a> Foo<'a> {
-    fn x(&self) -> &'a i32 { self.x }
-}
-
-fn main() {
-    let y = &5; // this is the same as `let _y = 5; let y = &_y;`
-    let f = Foo { x: y };
-
-    println!("x is: {}", f.x());
-}
-```
-
-As you can see, we need to declare a lifetime for `Foo` in the `impl` line. We repeat
-`'a` twice, just like on functions: `impl<'a>` defines a lifetime `'a`, and `Foo<'a>`
-uses it.
-
-## Multiple lifetimes
-
 If you have multiple references, you can use the same lifetime multiple times:
 
 ```rust

trunk/src/doc/trpl/unsafe.md

@@ -8,7 +8,7 @@ this, Rust has a keyword, `unsafe`. Code using `unsafe` has less restrictions
 than normal code does.
 
 Let’s go over the syntax, and then we’ll talk semantics. `unsafe` is used in
-four contexts. The first one is to mark a function as unsafe:
+two contexts. The first one is to mark a function as unsafe:
 
 ```rust
 unsafe fn danger_will_robinson() {
@@ -27,40 +27,15 @@ unsafe {
 }
 ```
 
-The third is for unsafe traits:
-
-```rust
-unsafe trait Scary { }
-```
-
-And the fourth is for `impl`ementing one of those traits:
-
-```rust
-# unsafe trait Scary { }
-unsafe impl Scary for i32 {}
-```
-
 It’s important to be able to explicitly delineate code that may have bugs that
 cause big problems. If a Rust program segfaults, you can be sure it’s somewhere
 in the sections marked `unsafe`.
 
 # What does ‘safe’ mean?
 
-Safe, in the context of Rust, means ‘doesn’t do anything unsafe’. It’s also
-important to know that there are certain behaviors that are probably not
-desirable in your code, but are expressly _not_ unsafe:
+Safe, in the context of Rust, means “doesn’t do anything unsafe.” Easy!
 
-* Deadlocks
-* Leaks of memory or other resources
-* Exiting without calling destructors
-* Integer overflow
-
-Rust cannot prevent all kinds of software problems. Buggy code can and will be
-written in Rust. These things aren’t great, but they don’t qualify as `unsafe`
-specifically.
-
-In addition, the following are all undefined behaviors in Rust, and must be
-avoided, even when writing `unsafe` code:
+Okay, let’s try again: what is not safe to do? Here’s a list:
 
 * Data races
 * Dereferencing a null/dangling raw pointer
@@ -89,6 +64,18 @@ avoided, even when writing `unsafe` code:
 [undef]: http://llvm.org/docs/LangRef.html#undefined-values
 [aliasing]: http://llvm.org/docs/LangRef.html#pointer-aliasing-rules
 
+Whew! That’s a bunch of stuff. It’s also important to notice all kinds of
+behaviors that are certainly bad, but are expressly _not_ unsafe:
+
+* Deadlocks
+* Leaks of memory or other resources
+* Exiting without calling destructors
+* Integer overflow
+
+Rust cannot prevent all kinds of software problems. Buggy code can and will be
+written in Rust. These things aren’t great, but they don’t qualify as `unsafe`
+specifically.
+
 # Unsafe Superpowers
 
 In both unsafe functions and unsafe blocks, Rust will let you do three things

trunk/src/libcore/fmt/mod.rs

@@ -273,6 +273,8 @@ impl<'a> Display for Arguments<'a> {
 ///
 /// Generally speaking, you should just `derive` a `Debug` implementation.
 ///
+/// When used with the alternate format specifier `#?`, the output is pretty-printed.
+///
 /// For more information on formatters, see [the module-level documentation][module].
 ///
 /// [module]: ../index.html
@@ -314,13 +316,42 @@ impl<'a> Display for Arguments<'a> {
 /// println!("The origin is: {:?}", origin);
 /// ```
 ///
+/// This outputs:
+///
+/// ```text
+/// The origin is: Point { x: 0, y: 0 }
+/// ```
+///
 /// There are a number of `debug_*` methods on `Formatter` to help you with manual
 /// implementations, such as [`debug_struct`][debug_struct].
 ///
 /// `Debug` implementations using either `derive` or the debug builder API
 /// on `Formatter` support pretty printing using the alternate flag: `{:#?}`.
 ///
 /// [debug_struct]: ../std/fmt/struct.Formatter.html#method.debug_struct
+///
+/// Pretty printing with `#?`:
+///
+/// ```
+/// #[derive(Debug)]
+/// struct Point {
+///     x: i32,
+///     y: i32,
+/// }
+///
+/// let origin = Point { x: 0, y: 0 };
+///
+/// println!("The origin is: {:#?}", origin);
+/// ```
+///
+/// This outputs:
+///
+/// ```text
+/// The origin is: Point {
+///     x: 0,
+///     y: 0
+/// }
+/// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_on_unimplemented = "`{Self}` cannot be formatted using `:?`; if it is \
                             defined in your crate, add `#[derive(Debug)]` or \
@@ -379,6 +410,8 @@ pub trait Display {
 ///
 /// The `Octal` trait should format its output as a number in base-8.
 ///
+/// The alternate flag, `#`, adds a `0o` in front of the output.
+///
 /// For more information on formatters, see [the module-level documentation][module].
 ///
 /// [module]: ../index.html
@@ -391,6 +424,7 @@ pub trait Display {
 /// let x = 42; // 42 is '52' in octal
 ///
 /// assert_eq!(format!("{:o}", x), "52");
+/// assert_eq!(format!("{:#o}", x), "0o52");
 /// ```
 ///
 /// Implementing `Octal` on a type:
@@ -423,6 +457,8 @@ pub trait Octal {
 ///
 /// The `Binary` trait should format its output as a number in binary.
 ///
+/// The alternate flag, `#`, adds a `0b` in front of the output.
+///
 /// For more information on formatters, see [the module-level documentation][module].
 ///
 /// [module]: ../index.html
@@ -435,6 +471,7 @@ pub trait Octal {
 /// let x = 42; // 42 is '101010' in binary
 ///
 /// assert_eq!(format!("{:b}", x), "101010");
+/// assert_eq!(format!("{:#b}", x), "0b101010");
 /// ```
 ///
 /// Implementing `Binary` on a type:
@@ -468,6 +505,8 @@ pub trait Binary {
 /// The `LowerHex` trait should format its output as a number in hexidecimal, with `a` through `f`
 /// in lower case.
 ///
+/// The alternate flag, `#`, adds a `0x` in front of the output.
+///
 /// For more information on formatters, see [the module-level documentation][module].
 ///
 /// [module]: ../index.html
@@ -480,6 +519,7 @@ pub trait Binary {
 /// let x = 42; // 42 is '2a' in hex
 ///
 /// assert_eq!(format!("{:x}", x), "2a");
+/// assert_eq!(format!("{:#x}", x), "0x2a");
 /// ```
 ///
 /// Implementing `LowerHex` on a type:
@@ -513,6 +553,8 @@ pub trait LowerHex {
 /// The `UpperHex` trait should format its output as a number in hexidecimal, with `A` through `F`
 /// in upper case.
 ///
+/// The alternate flag, `#`, adds a `0x` in front of the output.
+///
 /// For more information on formatters, see [the module-level documentation][module].
 ///
 /// [module]: ../index.html
@@ -525,6 +567,7 @@ pub trait LowerHex {
 /// let x = 42; // 42 is '2A' in hex
 ///
 /// assert_eq!(format!("{:X}", x), "2A");
+/// assert_eq!(format!("{:#X}", x), "0x2A");
 /// ```
 ///
 /// Implementing `UpperHex` on a type:

trunk/src/librustc/diagnostics.rs

@@ -1237,6 +1237,5 @@ register_diagnostics! {
     E0314, // closure outlives stack frame
     E0315, // cannot invoke closure outside of its lifetime
     E0316, // nested quantification of lifetimes
-    E0370, // discriminant overflow
-    E0400  // overloaded derefs are not allowed in constants
+    E0370  // discriminant overflow
 }

trunk/src/librustc/middle/cfg/construct.rs

@@ -332,7 +332,7 @@ impl<'a, 'tcx> CFGBuilder<'a, 'tcx> {
             }
 
             ast::ExprIndex(ref l, ref r) |
-            ast::ExprBinary(_, ref l, ref r) if self.tcx.is_method_call(expr.id) => {
+            ast::ExprBinary(_, ref l, ref r) if self.is_method_call(expr) => {
                 self.call(expr, pred, &**l, Some(&**r).into_iter())
             }
 
@@ -342,7 +342,7 @@ impl<'a, 'tcx> CFGBuilder<'a, 'tcx> {
                 self.straightline(expr, pred, fields)
             }
 
-            ast::ExprUnary(_, ref e) if self.tcx.is_method_call(expr.id) => {
+            ast::ExprUnary(_, ref e) if self.is_method_call(expr) => {
                 self.call(expr, pred, &**e, None::<ast::Expr>.iter())
             }
 
@@ -631,4 +631,9 @@ impl<'a, 'tcx> CFGBuilder<'a, 'tcx> {
             }
         }
     }
+
+    fn is_method_call(&self, expr: &ast::Expr) -> bool {
+        let method_call = ty::MethodCall::expr(expr.id);
+        self.tcx.tables.borrow().method_map.contains_key(&method_call)
+    }
 }

trunk/src/librustc/middle/check_const.rs

@@ -405,7 +405,6 @@ impl<'a, 'tcx, 'v> Visitor<'v> for CheckCrateVisitor<'a, 'tcx> {
 
         let node_ty = self.tcx.node_id_to_type(ex.id);
         check_expr(self, ex, node_ty);
-        check_adjustments(self, ex);
 
         // Special-case some expressions to avoid certain flags bubbling up.
         match ex.node {
@@ -778,25 +777,6 @@ fn check_expr<'a, 'tcx>(v: &mut CheckCrateVisitor<'a, 'tcx>,
     }
 }
 
-/// Check the adjustments of an expression
-fn check_adjustments<'a, 'tcx>(v: &mut CheckCrateVisitor<'a, 'tcx>, e: &ast::Expr) {
-    match v.tcx.tables.borrow().adjustments.get(&e.id) {
-        None | Some(&ty::AdjustReifyFnPointer) | Some(&ty::AdjustUnsafeFnPointer) => {}
-        Some(&ty::AdjustDerefRef(ty::AutoDerefRef { autoderefs, .. })) => {
-            if (0..autoderefs as u32).any(|autoderef| {
-                    v.tcx.is_overloaded_autoderef(e.id, autoderef)
-            }) {
-                v.add_qualif(ConstQualif::NOT_CONST);
-                if v.mode != Mode::Var {
-                    span_err!(v.tcx.sess, e.span, E0400,
-                              "user-defined dereference operators are not allowed in {}s",
-                              v.msg());
-                }
-            }
-        }
-    }
-}
-
 pub fn check_crate(tcx: &ty::ctxt) {
     visit::walk_crate(&mut CheckCrateVisitor {
         tcx: tcx,

trunk/src/librustc/middle/stability.rs

@@ -289,19 +289,15 @@ impl<'a, 'tcx> Checker<'a, 'tcx> {
         if !cross_crate { return }
 
         match *stab {
-            Some(&Stability { level: attr::Unstable, ref feature, ref reason, issue, .. }) => {
+            Some(&Stability { level: attr::Unstable, ref feature, ref reason, .. }) => {
                 self.used_features.insert(feature.clone(), attr::Unstable);
 
                 if !self.active_features.contains(feature) {
-                    let mut msg = match *reason {
+                    let msg = match *reason {
                         Some(ref r) => format!("use of unstable library feature '{}': {}",
                                                &feature, &r),
                         None => format!("use of unstable library feature '{}'", &feature)
                     };
-                    if let Some(n) = issue {
-                        use std::fmt::Write;
-                        write!(&mut msg, " (see issue #{})", n).unwrap();
-                    }
 
                     emit_feature_err(&self.tcx.sess.parse_sess.span_diagnostic,
                                       &feature, span, &msg);

trunk/src/librustc/middle/ty.rs

@@ -6631,11 +6631,6 @@ impl<'tcx> ctxt<'tcx> {
         self.tables.borrow().method_map.contains_key(&MethodCall::expr(expr_id))
     }
 
-    pub fn is_overloaded_autoderef(&self, expr_id: ast::NodeId, autoderefs: u32) -> bool {
-        self.tables.borrow().method_map.contains_key(&MethodCall::autoderef(expr_id,
-                                                                            autoderefs))
-    }
-
     pub fn upvar_capture(&self, upvar_id: ty::UpvarId) -> Option<ty::UpvarCapture> {
         Some(self.tables.borrow().upvar_capture_map.get(&upvar_id).unwrap().clone())
     }

trunk/src/librustc_driver/driver.rs

@@ -547,7 +547,7 @@ pub fn phase_2_configure_and_expand(sess: &Session,
                                                   sess.diagnostic()));
 
     krate = time(time_passes, "prelude injection", krate, |krate|
-                 syntax::std_inject::maybe_inject_prelude(&sess.parse_sess, krate));
+                 syntax::std_inject::maybe_inject_prelude(krate));
 
     time(time_passes, "checking that all macro invocations are gone", &krate, |krate|
          syntax::ext::expand::check_for_macros(&sess.parse_sess, krate));