Auto merge of #32495 - Manishearth:rollup, r=<try>

Rollup of 18 pull requests

- Successful merges: #32131, #32199, #32257, #32325, #32383, #32387, #32432, #32435, #32440, #32447, #32448, #32456, #32468, #32470, #32476, #32478, #32484, #32492
- Failed merges: #32240, #32469, #32482

configure

@@ -969,11 +969,11 @@ then
     LLVM_VERSION=$($LLVM_CONFIG --version)
 
     case $LLVM_VERSION in
-        (3.[5-8]*)
+        (3.[6-8]*)
             msg "found ok version of LLVM: $LLVM_VERSION"
             ;;
         (*)
-            err "bad LLVM version: $LLVM_VERSION, need >=3.5"
+            err "bad LLVM version: $LLVM_VERSION, need >=3.6"
             ;;
     esac
 fi

mk/crates.mk

@@ -57,7 +57,7 @@ TARGET_CRATES := libc std term \
 RUSTC_CRATES := rustc rustc_typeck rustc_mir rustc_borrowck rustc_resolve rustc_driver \
                 rustc_trans rustc_back rustc_llvm rustc_privacy rustc_lint \
                 rustc_data_structures rustc_front rustc_platform_intrinsics \
-                rustc_plugin rustc_metadata rustc_passes
+                rustc_plugin rustc_metadata rustc_passes rustc_save_analysis
 HOST_CRATES := syntax syntax_ext $(RUSTC_CRATES) rustdoc fmt_macros \
 		flate arena graphviz rbml log serialize
 TOOLS := compiletest rustdoc rustc rustbook error_index_generator
@@ -102,7 +102,7 @@ DEPS_rustc_data_structures := std log serialize
 DEPS_rustc_driver := arena flate getopts graphviz libc rustc rustc_back rustc_borrowck \
                      rustc_typeck rustc_mir rustc_resolve log syntax serialize rustc_llvm \
 	             rustc_trans rustc_privacy rustc_lint rustc_front rustc_plugin \
-                     rustc_metadata syntax_ext rustc_passes
+                     rustc_metadata syntax_ext rustc_passes rustc_save_analysis
 DEPS_rustc_front := std syntax log serialize
 DEPS_rustc_lint := rustc log syntax
 DEPS_rustc_llvm := native:rustllvm libc std rustc_bitflags
@@ -116,6 +116,7 @@ DEPS_rustc_privacy := rustc rustc_front log syntax
 DEPS_rustc_trans := arena flate getopts graphviz libc rustc rustc_back rustc_mir \
                     log syntax serialize rustc_llvm rustc_front rustc_platform_intrinsics \
 					rustc_const_eval
+DEPS_rustc_save_analysis := rustc log syntax rustc_front
 DEPS_rustc_typeck := rustc syntax rustc_front rustc_platform_intrinsics rustc_const_eval
 
 DEPS_rustdoc := rustc rustc_driver native:hoedown serialize getopts \

src/bootstrap/mk/Makefile.in

@@ -38,8 +38,8 @@ standalone-docs:
 	$(Q)$(BOOTSTRAP) --step doc-standalone
 check:
 	$(Q)$(BOOTSTRAP) --step check
-cargotest:
-	$(Q)$(BOOTSTRAP) --step cargotest
+check-cargotest:
+	$(Q)$(BOOTSTRAP) --step check-cargotest
 dist:
 	$(Q)$(BOOTSTRAP) --step dist
 

src/doc/book/strings.md

@@ -44,6 +44,11 @@ let s = "foo\
 assert_eq!("foobar", s);
 ```
 
+Note that you normally cannot access a `str` directly, but only through a `&str`
+reference. This is because `str` is an unsized type which requires additional
+runtime information to be usable. For more information see the chapter on
+[unsized types][ut].
+
 Rust has more than only `&str`s though. A `String` is a heap-allocated string.
 This string is growable, and is also guaranteed to be UTF-8. `String`s are
 commonly created by converting from a string slice using the `to_string`
@@ -185,5 +190,6 @@ let hello_world = hello + &world;
 This is because `&String` can automatically coerce to a `&str`. This is a
 feature called ‘[`Deref` coercions][dc]’.
 
+[ut]: unsized-types.html
 [dc]: deref-coercions.html
 [connect]: ../std/net/struct.TcpStream.html#method.connect

src/doc/reference.md

@@ -3911,6 +3911,9 @@ The _heap_ is a general term that describes boxes.  The lifetime of an
 allocation in the heap depends on the lifetime of the box values pointing to
 it. Since box values may themselves be passed in and out of frames, or stored
 in the heap, heap allocations may outlive the frame they are allocated within.
+An allocation in the heap is guaranteed to reside at a single location in the
+heap for the whole lifetime of the allocation - it will never be relocated as
+a result of moving a box value.
 
 ### Memory ownership
 

src/etc/CONFIGS.md

@@ -10,7 +10,3 @@ These are some links to repos with configs which ease the use of rust.
 * [kate-config](https://github.com/rust-lang/kate-config)
 * [nano-config](https://github.com/rust-lang/nano-config)
 * [zsh-config](https://github.com/rust-lang/zsh-config)
-
-## Community-maintained Configs
-
-* [.editorconfig](https://gist.github.com/derhuerst/c9d1b9309e308d9851fa) ([what is this?](http://editorconfig.org/))

src/libcore/str/mod.rs

@@ -1953,7 +1953,10 @@ impl StrExt for str {
 
     #[inline]
     fn is_char_boundary(&self, index: usize) -> bool {
-        if index == self.len() { return true; }
+        // 0 and len are always ok.
+        // Test for 0 explicitly so that it can optimize out the check
+        // easily and skip reading string data for that case.
+        if index == 0 || index == self.len() { return true; }
         match self.as_bytes().get(index) {
             None => false,
             Some(&b) => b < 128 || b >= 192,
@@ -2026,6 +2029,7 @@ impl StrExt for str {
         self.find(pat)
     }
 
+    #[inline]
     fn split_at(&self, mid: usize) -> (&str, &str) {
         // is_char_boundary checks that the index is in [0, .len()]
         if self.is_char_boundary(mid) {

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

@@ -9,10 +9,10 @@
 // except according to those terms.
 
 use rustc_data_structures::graph;
-use middle::cfg::*;
+use cfg::*;
 use middle::def::Def;
 use middle::pat_util;
-use middle::ty::{self, TyCtxt};
+use ty::{self, TyCtxt};
 use syntax::ast;
 use syntax::ptr::P;
 

src/librustc/middle/cfg/graphviz.rs → src/librustc/cfg/graphviz.rs

@@ -18,7 +18,7 @@ use graphviz::IntoCow;
 use syntax::ast;
 
 use front::map as ast_map;
-use middle::cfg;
+use cfg;
 
 pub type Node<'a> = (cfg::CFGIndex, &'a cfg::CFGNode);
 pub type Edge<'a> = &'a cfg::CFGEdge;

src/librustc/middle/cfg/mod.rs → src/librustc/cfg/mod.rs

@@ -12,7 +12,7 @@
 //! Uses `Graph` as the underlying representation.
 
 use rustc_data_structures::graph;
-use middle::ty::TyCtxt;
+use ty::TyCtxt;
 use syntax::ast;
 use rustc_front::hir;
 

src/librustc/dep_graph/mod.rs

@@ -11,7 +11,7 @@
 use self::thread::{DepGraphThreadData, DepMessage};
 use middle::def_id::DefId;
 use syntax::ast::NodeId;
-use middle::ty::TyCtxt;
+use ty::TyCtxt;
 use rustc_front::hir;
 use rustc_front::intravisit::Visitor;
 use std::rc::Rc;

src/librustc/diagnostics.rs

@@ -1261,7 +1261,7 @@ compiled:
 fn foo<T: Index<u8>>(x: T){}
 
 #[rustc_on_unimplemented = "the type `{Self}` cannot be indexed by `{Idx}`"]
-trait Index<Idx> { ... }
+trait Index<Idx> { /* ... */ }
 
 foo(true); // `bool` does not implement `Index<u8>`
 ```
@@ -1291,7 +1291,7 @@ compiled:
 fn foo<T: Index<u8>>(x: T){}
 
 #[rustc_on_unimplemented = "the type `{Self}` cannot be indexed by `{Idx}`"]
-trait Index<Idx> { ... }
+trait Index<Idx> { /* ... */ }
 
 foo(true); // `bool` does not implement `Index<u8>`
 ```
@@ -1319,7 +1319,7 @@ compiled:
 fn foo<T: Index<u8>>(x: T){}
 
 #[rustc_on_unimplemented = "the type `{Self}` cannot be indexed by `{Idx}`"]
-trait Index<Idx> { ... }
+trait Index<Idx> { /* ... */ }
 
 foo(true); // `bool` does not implement `Index<u8>`
 ```

src/librustc/middle/infer/bivariate.rs → src/librustc/infer/bivariate.rs

@@ -28,9 +28,9 @@
 use super::combine::{self, CombineFields};
 use super::type_variable::{BiTo};
 
-use middle::ty::{self, Ty, TyCtxt};
-use middle::ty::TyVar;
-use middle::ty::relate::{Relate, RelateResult, TypeRelation};
+use ty::{self, Ty, TyCtxt};
+use ty::TyVar;
+use ty::relate::{Relate, RelateResult, TypeRelation};
 
 pub struct Bivariate<'a, 'tcx: 'a> {
     fields: CombineFields<'a, 'tcx>

src/librustc/middle/infer/combine.rs → src/librustc/infer/combine.rs

@@ -41,11 +41,11 @@ use super::{InferCtxt};
 use super::{MiscVariable, TypeTrace};
 use super::type_variable::{RelationDir, BiTo, EqTo, SubtypeOf, SupertypeOf};
 
-use middle::ty::{IntType, UintType};
-use middle::ty::{self, Ty, TyCtxt};
-use middle::ty::error::TypeError;
-use middle::ty::fold::{TypeFolder, TypeFoldable};
-use middle::ty::relate::{Relate, RelateResult, TypeRelation};
+use ty::{IntType, UintType};
+use ty::{self, Ty, TyCtxt};
+use ty::error::TypeError;
+use ty::fold::{TypeFolder, TypeFoldable};
+use ty::relate::{Relate, RelateResult, TypeRelation};
 
 use syntax::ast;
 use syntax::codemap::Span;

src/librustc/middle/infer/equate.rs → src/librustc/infer/equate.rs

@@ -13,9 +13,9 @@ use super::higher_ranked::HigherRankedRelations;
 use super::{Subtype};
 use super::type_variable::{EqTo};
 
-use middle::ty::{self, Ty, TyCtxt};
-use middle::ty::TyVar;
-use middle::ty::relate::{Relate, RelateResult, TypeRelation};
+use ty::{self, Ty, TyCtxt};
+use ty::TyVar;
+use ty::relate::{Relate, RelateResult, TypeRelation};
 
 /// Ensures `a` is made equal to `b`. Returns `a` on success.
 pub struct Equate<'a, 'tcx: 'a> {

src/librustc/middle/infer/error_reporting.rs → src/librustc/infer/error_reporting.rs

@@ -80,12 +80,12 @@ use rustc_front::print::pprust;
 use middle::cstore::CrateStore;
 use middle::def::Def;
 use middle::def_id::DefId;
-use middle::infer::{self, TypeOrigin};
+use infer::{self, TypeOrigin};
 use middle::region;
-use middle::subst;
-use middle::ty::{self, Ty, TyCtxt, TypeFoldable};
-use middle::ty::{Region, ReFree};
-use middle::ty::error::TypeError;
+use ty::subst;
+use ty::{self, Ty, TyCtxt, TypeFoldable};
+use ty::{Region, ReFree};
+use ty::error::TypeError;
 
 use std::cell::{Cell, RefCell};
 use std::char::from_u32;

src/librustc/middle/infer/freshen.rs → src/librustc/infer/freshen.rs

@@ -30,8 +30,8 @@
 //! variable only once, and it does so as soon as it can, so it is reasonable to ask what the type
 //! inferencer knows "so far".
 
-use middle::ty::{self, Ty, TyCtxt, TypeFoldable};
-use middle::ty::fold::TypeFolder;
+use ty::{self, Ty, TyCtxt, TypeFoldable};
+use ty::fold::TypeFolder;
 use std::collections::hash_map::{self, Entry};
 
 use super::InferCtxt;

src/librustc/middle/infer/glb.rs → src/librustc/infer/glb.rs

@@ -14,8 +14,8 @@ use super::InferCtxt;
 use super::lattice::{self, LatticeDir};
 use super::Subtype;
 
-use middle::ty::{self, Ty, TyCtxt};
-use middle::ty::relate::{Relate, RelateResult, TypeRelation};
+use ty::{self, Ty, TyCtxt};
+use ty::relate::{Relate, RelateResult, TypeRelation};
 
 /// "Greatest lower bound" (common subtype)
 pub struct Glb<'a, 'tcx: 'a> {

src/librustc/middle/infer/higher_ranked/mod.rs → src/librustc/infer/higher_ranked/mod.rs

@@ -14,9 +14,9 @@
 use super::{CombinedSnapshot, InferCtxt, HigherRankedType, SkolemizationMap};
 use super::combine::CombineFields;
 
-use middle::ty::{self, TyCtxt, Binder, TypeFoldable};
-use middle::ty::error::TypeError;
-use middle::ty::relate::{Relate, RelateResult, TypeRelation};
+use ty::{self, TyCtxt, Binder, TypeFoldable};
+use ty::error::TypeError;
+use ty::relate::{Relate, RelateResult, TypeRelation};
 use syntax::codemap::Span;
 use util::nodemap::{FnvHashMap, FnvHashSet};
 

src/librustc/middle/infer/lattice.rs → src/librustc/infer/lattice.rs

@@ -32,9 +32,9 @@
 use super::combine;
 use super::InferCtxt;
 
-use middle::ty::TyVar;
-use middle::ty::{self, Ty};
-use middle::ty::relate::{RelateResult, TypeRelation};
+use ty::TyVar;
+use ty::{self, Ty};
+use ty::relate::{RelateResult, TypeRelation};
 
 pub trait LatticeDir<'f,'tcx> : TypeRelation<'f,'tcx> {
     fn infcx(&self) -> &'f InferCtxt<'f, 'tcx>;

src/librustc/middle/infer/lub.rs → src/librustc/infer/lub.rs

@@ -14,8 +14,8 @@ use super::InferCtxt;
 use super::lattice::{self, LatticeDir};
 use super::Subtype;
 
-use middle::ty::{self, Ty, TyCtxt};
-use middle::ty::relate::{Relate, RelateResult, TypeRelation};
+use ty::{self, Ty, TyCtxt};
+use ty::relate::{Relate, RelateResult, TypeRelation};
 
 /// "Least upper bound" (common supertype)
 pub struct Lub<'a, 'tcx: 'a> {

src/librustc/middle/infer/mod.rs → src/librustc/infer/mod.rs

@@ -14,7 +14,7 @@ pub use self::LateBoundRegionConversionTime::*;
 pub use self::RegionVariableOrigin::*;
 pub use self::SubregionOrigin::*;
 pub use self::ValuePairs::*;
-pub use middle::ty::IntVarValue;
+pub use ty::IntVarValue;
 pub use self::freshen::TypeFreshener;
 pub use self::region_inference::{GenericKind, VerifyBound};
 
@@ -24,16 +24,16 @@ use middle::free_region::FreeRegionMap;
 use middle::mem_categorization as mc;
 use middle::mem_categorization::McResult;
 use middle::region::CodeExtent;
-use middle::subst;
-use middle::subst::Substs;
-use middle::subst::Subst;
-use middle::traits::{self, ProjectionMode};
-use middle::ty::adjustment;
-use middle::ty::{TyVid, IntVid, FloatVid};
-use middle::ty::{self, Ty, TyCtxt};
-use middle::ty::error::{ExpectedFound, TypeError, UnconstrainedNumeric};
-use middle::ty::fold::{TypeFolder, TypeFoldable};
-use middle::ty::relate::{Relate, RelateResult, TypeRelation};
+use ty::subst;
+use ty::subst::Substs;
+use ty::subst::Subst;
+use traits::{self, ProjectionMode};
+use ty::adjustment;
+use ty::{TyVid, IntVid, FloatVid};
+use ty::{self, Ty, TyCtxt};
+use ty::error::{ExpectedFound, TypeError, UnconstrainedNumeric};
+use ty::fold::{TypeFolder, TypeFoldable};
+use ty::relate::{Relate, RelateResult, TypeRelation};
 use rustc_data_structures::unify::{self, UnificationTable};
 use std::cell::{RefCell, Ref};
 use std::fmt;
@@ -622,8 +622,8 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
     }
 
     pub fn type_is_unconstrained_numeric(&'a self, ty: Ty) -> UnconstrainedNumeric {
-        use middle::ty::error::UnconstrainedNumeric::Neither;
-        use middle::ty::error::UnconstrainedNumeric::{UnconstrainedInt, UnconstrainedFloat};
+        use ty::error::UnconstrainedNumeric::Neither;
+        use ty::error::UnconstrainedNumeric::{UnconstrainedInt, UnconstrainedFloat};
         match ty.sty {
             ty::TyInfer(ty::IntVar(vid)) => {
                 if self.int_unification_table.borrow_mut().has_value(vid) {

src/librustc/middle/infer/region_inference/graphviz.rs → src/librustc/infer/region_inference/graphviz.rs

@@ -18,11 +18,11 @@
 /// For clarity, rename the graphviz crate locally to dot.
 use graphviz as dot;
 
-use middle::ty::{self, TyCtxt};
+use ty::{self, TyCtxt};
 use middle::region::CodeExtent;
 use super::Constraint;
-use middle::infer::SubregionOrigin;
-use middle::infer::region_inference::RegionVarBindings;
+use infer::SubregionOrigin;
+use infer::region_inference::RegionVarBindings;
 use util::nodemap::{FnvHashMap, FnvHashSet};
 
 use std::borrow::Cow;

src/librustc/middle/infer/region_inference/mod.rs → src/librustc/infer/region_inference/mod.rs

@@ -23,10 +23,10 @@ use super::unify_key;
 use rustc_data_structures::graph::{self, Direction, NodeIndex};
 use rustc_data_structures::unify::{self, UnificationTable};
 use middle::free_region::FreeRegionMap;
-use middle::ty::{self, Ty, TyCtxt};
-use middle::ty::{BoundRegion, Region, RegionVid};
-use middle::ty::{ReEmpty, ReStatic, ReFree, ReEarlyBound};
-use middle::ty::{ReLateBound, ReScope, ReVar, ReSkolemized, BrFresh};
+use ty::{self, Ty, TyCtxt};
+use ty::{BoundRegion, Region, RegionVid};
+use ty::{ReEmpty, ReStatic, ReFree, ReEarlyBound};
+use ty::{ReLateBound, ReScope, ReVar, ReSkolemized, BrFresh};
 use util::common::indenter;
 use util::nodemap::{FnvHashMap, FnvHashSet};
 

src/librustc/middle/infer/resolve.rs → src/librustc/infer/resolve.rs

@@ -9,7 +9,7 @@
 // except according to those terms.
 
 use super::{InferCtxt, FixupError, FixupResult};
-use middle::ty::{self, Ty, TyCtxt, TypeFoldable};
+use ty::{self, Ty, TyCtxt, TypeFoldable};
 
 ///////////////////////////////////////////////////////////////////////////
 // OPPORTUNISTIC TYPE RESOLVER

src/librustc/middle/infer/sub.rs → src/librustc/infer/sub.rs

@@ -13,9 +13,9 @@ use super::higher_ranked::HigherRankedRelations;
 use super::SubregionOrigin;
 use super::type_variable::{SubtypeOf, SupertypeOf};
 
-use middle::ty::{self, Ty, TyCtxt};
-use middle::ty::TyVar;
-use middle::ty::relate::{Cause, Relate, RelateResult, TypeRelation};
+use ty::{self, Ty, TyCtxt};
+use ty::TyVar;
+use ty::relate::{Cause, Relate, RelateResult, TypeRelation};
 use std::mem;
 
 /// Ensures `a` is made a subtype of `b`. Returns `a` on success.