Auto merge of #33049 - Manishearth:rollup, r=Manishearth

Rollup of 10 pull requests

- Successful merges: #31441, #32956, #33003, #33022, #33023, #33032, #33039, #33044, #33045, #33046
- Failed merges:

CONTRIBUTING.md

@@ -307,7 +307,7 @@ are:
 [gsearchdocs]: https://www.google.com/search?q=site:doc.rust-lang.org+your+query+here
 [rif]: http://internals.rust-lang.org
 [rr]: https://doc.rust-lang.org/book/README.html
-[tlgba]: http://tomlee.co/2014/04/03/a-more-detailed-tour-of-the-rust-compiler/
+[tlgba]: http://tomlee.co/2014/04/a-more-detailed-tour-of-the-rust-compiler/
 [ro]: http://www.rustaceans.org/
 [rctd]: ./COMPILER_TESTS.md
 [cheatsheet]: http://buildbot.rust-lang.org/homu/

src/doc/book/casting-between-types.md

@@ -165,10 +165,15 @@ Rust lets us:
 ```rust
 use std::mem;
 
-unsafe {
- let a = [0u8, 0u8, 0u8, 0u8];
-
- let b = mem::transmute::<[u8; 4], u32>(a);
+fn main() {
+ unsafe {
+ let a = [0u8, 1u8, 0u8, 0u8];
+ let b = mem::transmute::<[u8; 4], u32>(a);
+ println!("{}", b); // 256
+ // or, more concisely:
+ let c: u32 = mem::transmute(a);
+ println!("{}", c); // 256
+ }
 }
 ```
 

src/libcore/num/mod.rs

@@ -38,9 +38,23 @@ use slice::SliceExt;
 /// all standard arithmetic operations on the underlying value are
 /// intended to have wrapping semantics.
 #[stable(feature = "rust1", since = "1.0.0")]
-#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Debug, Default)]
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Default, Hash)]
 pub struct Wrapping<T>(#[stable(feature = "rust1", since = "1.0.0")] pub T);
 
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<T: fmt::Debug> fmt::Debug for Wrapping<T> {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ self.0.fmt(f)
+ }
+}
+
+#[stable(feature = "wrapping_display", since = "1.10.0")]
+impl<T: fmt::Display> fmt::Display for Wrapping<T> {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ self.0.fmt(f)
+ }
+}
+
 mod wrapping;
 
 // All these modules are technically private and only exposed for libcoretest:

src/libcore/ptr.rs

@@ -119,6 +119,17 @@ pub unsafe fn replace<T>(dest: *mut T, mut src: T) -> T {
 /// `src` is not used before the data is overwritten again (e.g. with `write`,
 /// `zero_memory`, or `copy_memory`). Note that `*src = foo` counts as a use
 /// because it will attempt to drop the value previously at `*src`.
+///
+/// # Examples
+///
+/// Basic usage:
+///
+/// ```
+/// let x = 12;
+/// let y = &x as *const i32;
+///
+/// unsafe { println!("{}", std::ptr::read(y)); }
+/// ```
 #[inline(always)]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub unsafe fn read<T>(src: *const T) -> T {
@@ -155,6 +166,21 @@ pub unsafe fn read_and_drop<T>(dest: *mut T) -> T {
 ///
 /// This is appropriate for initializing uninitialized memory, or overwriting
 /// memory that has previously been `read` from.
+///
+/// # Examples
+///
+/// Basic usage:
+///
+/// ```
+/// let mut x = 0;
+/// let y = &mut x as *mut i32;
+/// let z = 12;
+///
+/// unsafe {
+/// std::ptr::write(y, z);
+/// println!("{}", std::ptr::read(y));
+/// }
+/// ```
 #[inline]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub unsafe fn write<T>(dst: *mut T, src: T) {
@@ -185,6 +211,17 @@ pub unsafe fn write<T>(dst: *mut T, src: T) {
 /// `src` is not used before the data is overwritten again (e.g. with `write`,
 /// `zero_memory`, or `copy_memory`). Note that `*src = foo` counts as a use
 /// because it will attempt to drop the value previously at `*src`.
+///
+/// # Examples
+///
+/// Basic usage:
+///
+/// ```
+/// let x = 12;
+/// let y = &x as *const i32;
+///
+/// unsafe { println!("{}", std::ptr::read_volatile(y)); }
+/// ```
 #[inline]
 #[stable(feature = "volatile", since = "1.9.0")]
 pub unsafe fn read_volatile<T>(src: *const T) -> T {
@@ -217,6 +254,21 @@ pub unsafe fn read_volatile<T>(src: *const T) -> T {
 ///
 /// This is appropriate for initializing uninitialized memory, or overwriting
 /// memory that has previously been `read` from.
+///
+/// # Examples
+///
+/// Basic usage:
+///
+/// ```
+/// let mut x = 0;
+/// let y = &mut x as *mut i32;
+/// let z = 12;
+///
+/// unsafe {
+/// std::ptr::write_volatile(y, z);
+/// println!("{}", std::ptr::read_volatile(y));
+/// }
+/// ```
 #[inline]
 #[stable(feature = "volatile", since = "1.9.0")]
 pub unsafe fn write_volatile<T>(dst: *mut T, src: T) {

src/librustc_resolve/Cargo.toml

@@ -12,5 +12,4 @@ crate-type = ["dylib"]
 log = { path = "../liblog" }
 syntax = { path = "../libsyntax" }
 rustc = { path = "../librustc" }
-rustc_bitflags = { path = "../librustc_bitflags" }
 arena = { path = "../libarena" }

src/librustc_resolve/build_reduced_graph.rs

@@ -13,7 +13,6 @@
 //! Here we build the "reduced graph": the graph of the module tree without
 //! any imports resolved.
 
-use DefModifiers;
 use resolve_imports::ImportDirectiveSubclass::{self, GlobImport};
 use Module;
 use Namespace::{self, TypeNS, ValueNS};
@@ -28,9 +27,9 @@ use rustc::hir::def::*;
 use rustc::hir::def_id::{CRATE_DEF_INDEX, DefId};
 use rustc::ty::{self, VariantKind};
 
-use syntax::ast::Name;
+use syntax::ast::{Name, NodeId};
 use syntax::attr::AttrMetaMethods;
-use syntax::parse::token::{special_idents, SELF_KEYWORD_NAME, SUPER_KEYWORD_NAME};
+use syntax::parse::token::keywords;
 use syntax::codemap::{Span, DUMMY_SP};
 
 use rustc::hir;
@@ -53,10 +52,9 @@ impl<'a> ToNameBinding<'a> for (Module<'a>, Span) {
  }
 }
 
-impl<'a> ToNameBinding<'a> for (Def, Span, DefModifiers, ty::Visibility) {
+impl<'a> ToNameBinding<'a> for (Def, Span, ty::Visibility) {
  fn to_name_binding(self) -> NameBinding<'a> {
- let kind = NameBindingKind::Def(self.0);
- NameBinding { modifiers: self.2, kind: kind, span: Some(self.1), vis: self.3 }
+ NameBinding { kind: NameBindingKind::Def(self.0), span: Some(self.1), vis: self.2 }
  }
 }
 
@@ -100,12 +98,42 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
  block.stmts.iter().any(is_item)
  }
 
+ fn sanity_check_import(&self, view_path: &hir::ViewPath, id: NodeId) {
+ let path = match view_path.node {
+ ViewPathSimple(_, ref path) |
+ ViewPathGlob (ref path) |
+ ViewPathList(ref path, _) => path
+ };
+
+ // Check for type parameters
+ let found_param = path.segments.iter().any(|segment| {
+ !segment.parameters.types().is_empty() ||
+ !segment.parameters.lifetimes().is_empty() ||
+ !segment.parameters.bindings().is_empty()
+ });
+ if found_param {
+ self.session.span_err(path.span,
+ "type or lifetime parameter is found in import path");
+ }
+
+ // Checking for special identifiers in path
+ // prevent `self` or `super` at beginning of global path
+ if path.global && path.segments.len() > 0 {
+ let first = path.segments[0].identifier.name;
+ if first == keywords::Super.to_name() || first == keywords::SelfValue.to_name() {
+ self.session.add_lint(
+ lint::builtin::SUPER_OR_SELF_IN_GLOBAL_PATH, id, path.span,
+ format!("expected identifier, found keyword `{}`", first)
+ );
+ }
+ }
+ }
+
  /// Constructs the reduced graph for one item.
  fn build_reduced_graph_for_item(&mut self, item: &Item, parent_ref: &mut Module<'b>) {
  let parent = *parent_ref;
  let name = item.name;
  let sp = item.span;
- let modifiers = DefModifiers::IMPORTABLE;
  self.current_module = parent;
  let vis = self.resolve_visibility(&item.vis);
 
@@ -114,10 +142,8 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
  // Extract and intern the module part of the path. For
  // globs and lists, the path is found directly in the AST;
  // for simple paths we have to munge the path a little.
- let is_global;
  let module_path: Vec<Name> = match view_path.node {
  ViewPathSimple(_, ref full_path) => {
- is_global = full_path.global;
  full_path.segments
  .split_last()
  .unwrap()
@@ -129,30 +155,17 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
 
  ViewPathGlob(ref module_ident_path) |
  ViewPathList(ref module_ident_path, _) => {
- is_global = module_ident_path.global;
  module_ident_path.segments
  .iter()
  .map(|seg| seg.identifier.name)
  .collect()
  }
  };
 
- // Checking for special identifiers in path
- // prevent `self` or `super` at beginning of global path
- if is_global && (module_path.first() == Some(&SELF_KEYWORD_NAME) ||
- module_path.first() == Some(&SUPER_KEYWORD_NAME)) {
- self.session.add_lint(
- lint::builtin::SUPER_OR_SELF_IN_GLOBAL_PATH,
- item.id,
- item.span,
- format!("expected identifier, found keyword `{}`",
- module_path.first().unwrap().as_str()));
- }
+ self.sanity_check_import(view_path, item.id);
 
  // Build up the import directives.
- let is_prelude = item.attrs.iter().any(|attr| {
- attr.name() == special_idents::prelude_import.name.as_str()
- });
+ let is_prelude = item.attrs.iter().any(|attr| attr.name() == "prelude_import");
 
  match view_path.node {
  ViewPathSimple(binding, ref full_path) => {
@@ -268,21 +281,21 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
  ItemStatic(_, m, _) => {
  let mutbl = m == hir::MutMutable;
  let def = Def::Static(self.ast_map.local_def_id(item.id), mutbl);
- self.define(parent, name, ValueNS, (def, sp, modifiers, vis));
+ self.define(parent, name, ValueNS, (def, sp, vis));
  }
  ItemConst(_, _) => {
  let def = Def::Const(self.ast_map.local_def_id(item.id));
- self.define(parent, name, ValueNS, (def, sp, modifiers, vis));
+ self.define(parent, name, ValueNS, (def, sp, vis));
  }
  ItemFn(_, _, _, _, _, _) => {
  let def = Def::Fn(self.ast_map.local_def_id(item.id));
- self.define(parent, name, ValueNS, (def, sp, modifiers, vis));
+ self.define(parent, name, ValueNS, (def, sp, vis));
  }
 
  // These items live in the type namespace.
  ItemTy(..) => {
  let def = Def::TyAlias(self.ast_map.local_def_id(item.id));
- self.define(parent, name, TypeNS, (def, sp, modifiers, vis));
+ self.define(parent, name, TypeNS, (def, sp, vis));
  }
 
  ItemEnum(ref enum_definition, _) => {
@@ -301,13 +314,13 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
  ItemStruct(ref struct_def, _) => {
  // Define a name in the type namespace.
  let def = Def::Struct(self.ast_map.local_def_id(item.id));
- self.define(parent, name, TypeNS, (def, sp, modifiers, vis));
+ self.define(parent, name, TypeNS, (def, sp, vis));
 
  // If this is a newtype or unit-like struct, define a name
  // in the value namespace as well
  if !struct_def.is_struct() {
  let def = Def::Struct(self.ast_map.local_def_id(struct_def.id()));
- self.define(parent, name, ValueNS, (def, sp, modifiers, vis));
+ self.define(parent, name, ValueNS, (def, sp, vis));
  }
 
  // Record the def ID and fields of this struct.
@@ -339,8 +352,7 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
  hir::TypeTraitItem(..) => (Def::AssociatedTy(def_id, item_def_id), TypeNS),
  };
 
- let modifiers = DefModifiers::empty(); // NB: not DefModifiers::IMPORTABLE
- self.define(module_parent, item.name, ns, (def, item.span, modifiers, vis));
+ self.define(module_parent, item.name, ns, (def, item.span, vis));
 
  self.trait_item_map.insert((item.name, def_id), item_def_id);
  }
@@ -363,19 +375,16 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
 
  // Variants are always treated as importable to allow them to be glob used.
  // All variants are defined in both type and value namespaces as future-proofing.
- let modifiers = DefModifiers::IMPORTABLE;
  let def = Def::Variant(item_id, self.ast_map.local_def_id(variant.node.data.id()));
-
- self.define(parent, name, ValueNS, (def, variant.span, modifiers, parent.vis));
- self.define(parent, name, TypeNS, (def, variant.span, modifiers, parent.vis));
+ self.define(parent, name, ValueNS, (def, variant.span, parent.vis));
+ self.define(parent, name, TypeNS, (def, variant.span, parent.vis));
  }
 
  /// Constructs the reduced graph for one foreign item.
  fn build_reduced_graph_for_foreign_item(&mut self,
  foreign_item: &ForeignItem,
  parent: Module<'b>) {
  let name = foreign_item.name;
- let modifiers = DefModifiers::IMPORTABLE;
 
  let def = match foreign_item.node {
  ForeignItemFn(..) => {
@@ -387,7 +396,7 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
  };
  self.current_module = parent;
  let vis = self.resolve_visibility(&foreign_item.vis);
- self.define(parent, name, ValueNS, (def, foreign_item.span, modifiers, vis));
+ self.define(parent, name, ValueNS, (def, foreign_item.span, vis));
  }
 
  fn build_reduced_graph_for_block(&mut self, block: &Block, parent: &mut Module<'b>) {
@@ -422,10 +431,6 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
 
  let name = xcdef.name;
  let vis = if parent.is_trait() { ty::Visibility::Public } else { xcdef.vis };
- let modifiers = match parent.is_normal() {
- true => DefModifiers::IMPORTABLE,
- false => DefModifiers::empty(),
- };
 
  match def {
  Def::Mod(_) | Def::ForeignMod(_) | Def::Enum(..) => {
@@ -439,9 +444,8 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
  debug!("(building reduced graph for external crate) building variant {}", name);
  // Variants are always treated as importable to allow them to be glob used.
  // All variants are defined in both type and value namespaces as future-proofing.
- let modifiers = DefModifiers::IMPORTABLE;
- self.try_define(parent, name, TypeNS, (def, DUMMY_SP, modifiers, vis));
- self.try_define(parent, name, ValueNS, (def, DUMMY_SP, modifiers, vis));
+ self.try_define(parent, name, TypeNS, (def, DUMMY_SP, vis));
+ self.try_define(parent, name, ValueNS, (def, DUMMY_SP, vis));
  if self.session.cstore.variant_kind(variant_id) == Some(VariantKind::Struct) {
  // Not adding fields for variants as they are not accessed with a self receiver
  self.structs.insert(variant_id, Vec::new());
@@ -454,7 +458,7 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
  Def::Method(..) => {
  debug!("(building reduced graph for external crate) building value (fn/static) {}",
  name);
- self.try_define(parent, name, ValueNS, (def, DUMMY_SP, modifiers, vis));
+ self.try_define(parent, name, ValueNS, (def, DUMMY_SP, vis));
  }
  Def::Trait(def_id) => {
  debug!("(building reduced graph for external crate) building type {}", name);
@@ -480,16 +484,16 @@ impl<'b, 'tcx:'b> Resolver<'b, 'tcx> {
  }
  Def::TyAlias(..) | Def::AssociatedTy(..) => {
  debug!("(building reduced graph for external crate) building type {}", name);
- self.try_define(parent, name, TypeNS, (def, DUMMY_SP, modifiers, vis));
+ self.try_define(parent, name, TypeNS, (def, DUMMY_SP, vis));
  }
  Def::Struct(def_id)
  if self.session.cstore.tuple_struct_definition_if_ctor(def_id).is_none() => {
  debug!("(building reduced graph for external crate) building type and value for {}",
  name);
- self.try_define(parent, name, TypeNS, (def, DUMMY_SP, modifiers, vis));
+ self.try_define(parent, name, TypeNS, (def, DUMMY_SP, vis));
  if let Some(ctor_def_id) = self.session.cstore.struct_ctor_def_id(def_id) {
  let def = Def::Struct(ctor_def_id);
- self.try_define(parent, name, ValueNS, (def, DUMMY_SP, modifiers, vis));
+ self.try_define(parent, name, ValueNS, (def, DUMMY_SP, vis));
  }
 
  // Record the def ID and fields of this struct.