Auto merge of #47900 - kennytm:rollup, r=kennytm

Rollup of 16 pull requests

- Successful merges: #47838, #47840, #47844, #47874, #47875, #47876, #47884, #47886, #47889, #47890, #47891, #47795, #47677, #47893, #47895, #47552
- Failed merges:

43 files changed, 320 insertions, 48 deletions

diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index 1272643edd2..780513dd943 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -377,6 +377,11 @@ impl<'a> Builder<'a> {
         self.ensure(Libdir { compiler, target })
     }
 
+    pub fn sysroot_codegen_backends(&self, compiler: Compiler) -> PathBuf {
+        self.sysroot_libdir(compiler, compiler.host)
+            .with_file_name("codegen-backends")
+    }
+
     /// Returns the compiler's libdir where it stores the dynamic libraries that
     /// it itself links against.
     ///
diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs
index fa289bbd76a..1d5e11c5d6d 100644
--- a/src/bootstrap/compile.rs
+++ b/src/bootstrap/compile.rs
@@ -724,8 +724,7 @@ fn copy_codegen_backends_to_sysroot(builder: &Builder,
     //
     // Here we're looking for the output dylib of the `CodegenBackend` step and
     // we're copying that into the `codegen-backends` folder.
-    let libdir = builder.sysroot_libdir(target_compiler, target);
-    let dst = libdir.join("codegen-backends");
+    let dst = builder.sysroot_codegen_backends(target_compiler);
     t!(fs::create_dir_all(&dst));
 
     for backend in builder.config.rust_codegen_backends.iter() {
diff --git a/src/bootstrap/dist.rs b/src/bootstrap/dist.rs
index 4127239dc49..dbb7d19e432 100644
--- a/src/bootstrap/dist.rs
+++ b/src/bootstrap/dist.rs
@@ -435,11 +435,9 @@ impl Step for Rustc {
             }
 
             // Copy over the codegen backends
-            let backends_src = builder.sysroot_libdir(compiler, host)
-                .join("codegen-backends");
-            let backends_dst = image.join("lib/rustlib")
-                .join(&*host)
-                .join("lib/codegen-backends");
+            let backends_src = builder.sysroot_codegen_backends(compiler);
+            let backends_rel = backends_src.strip_prefix(&src).unwrap();
+            let backends_dst = image.join(&backends_rel);
             t!(fs::create_dir_all(&backends_dst));
             cp_r(&backends_src, &backends_dst);
 
diff --git a/src/libcore/fmt/mod.rs b/src/libcore/fmt/mod.rs
index 65aacb23bd7..6c8a1c3062b 100644
--- a/src/libcore/fmt/mod.rs
+++ b/src/libcore/fmt/mod.rs
@@ -1586,6 +1586,7 @@ impl Display for ! {
 
 #[stable(feature = "rust1", since = "1.0.0")]
 impl Debug for bool {
+    #[inline]
     fn fmt(&self, f: &mut Formatter) -> Result {
         Display::fmt(self, f)
     }
@@ -1748,6 +1749,7 @@ impl<T: Debug> Debug for [T] {
 
 #[stable(feature = "rust1", since = "1.0.0")]
 impl Debug for () {
+    #[inline]
     fn fmt(&self, f: &mut Formatter) -> Result {
         f.pad("()")
     }
diff --git a/src/libcore/fmt/num.rs b/src/libcore/fmt/num.rs
index ee989854a37..2992e7cf8db 100644
--- a/src/libcore/fmt/num.rs
+++ b/src/libcore/fmt/num.rs
@@ -157,6 +157,7 @@ macro_rules! debug {
     ($T:ident) => {
         #[stable(feature = "rust1", since = "1.0.0")]
         impl fmt::Debug for $T {
+            #[inline]
             fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
                 fmt::Display::fmt(self, f)
             }
diff --git a/src/libcore/iter/mod.rs b/src/libcore/iter/mod.rs
index 06c29b47bf9..7314fac282b 100644
--- a/src/libcore/iter/mod.rs
+++ b/src/libcore/iter/mod.rs
@@ -307,6 +307,7 @@ use fmt;
 use iter_private::TrustedRandomAccess;
 use ops::Try;
 use usize;
+use intrinsics;
 
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use self::iterator::Iterator;
@@ -694,6 +695,49 @@ impl<I> Iterator for StepBy<I> where I: Iterator {
             (f(inner_hint.0), inner_hint.1.map(f))
         }
     }
+
+    #[inline]
+    fn nth(&mut self, mut n: usize) -> Option<Self::Item> {
+        if self.first_take {
+            self.first_take = false;
+            let first = self.iter.next();
+            if n == 0 {
+                return first;
+            }
+            n -= 1;
+        }
+        // n and self.step are indices, we need to add 1 to get the amount of elements
+        // When calling `.nth`, we need to subtract 1 again to convert back to an index
+        // step + 1 can't overflow because `.step_by` sets `self.step` to `step - 1`
+        let mut step = self.step + 1;
+        // n + 1 could overflow
+        // thus, if n is usize::MAX, instead of adding one, we call .nth(step)
+        if n == usize::MAX {
+            self.iter.nth(step - 1);
+        } else {
+            n += 1;
+        }
+
+        // overflow handling
+        loop {
+            let mul = n.checked_mul(step);
+            if unsafe { intrinsics::likely(mul.is_some()) } {
+                return self.iter.nth(mul.unwrap() - 1);
+            }
+            let div_n = usize::MAX / n;
+            let div_step = usize::MAX / step;
+            let nth_n = div_n * n;
+            let nth_step = div_step * step;
+            let nth = if nth_n > nth_step {
+                step -= div_n;
+                nth_n
+            } else {
+                n -= div_step;
+                nth_step
+            };
+            self.iter.nth(nth - 1);
+        }
+    }
 }
 
 // StepBy can only make the iterator shorter, so the len will still fit.
diff --git a/src/libcore/tests/iter.rs b/src/libcore/tests/iter.rs
index 8997cf9c6bf..e52e119ff59 100644
--- a/src/libcore/tests/iter.rs
+++ b/src/libcore/tests/iter.rs
@@ -162,6 +162,68 @@ fn test_iterator_step_by() {
 }
 
 #[test]
+fn test_iterator_step_by_nth() {
+    let mut it = (0..16).step_by(5);
+    assert_eq!(it.nth(0), Some(0));
+    assert_eq!(it.nth(0), Some(5));
+    assert_eq!(it.nth(0), Some(10));
+    assert_eq!(it.nth(0), Some(15));
+    assert_eq!(it.nth(0), None);
+
+    let it = (0..18).step_by(5);
+    assert_eq!(it.clone().nth(0), Some(0));
+    assert_eq!(it.clone().nth(1), Some(5));
+    assert_eq!(it.clone().nth(2), Some(10));
+    assert_eq!(it.clone().nth(3), Some(15));
+    assert_eq!(it.clone().nth(4), None);
+    assert_eq!(it.clone().nth(42), None);
+}
+
+#[test]
+fn test_iterator_step_by_nth_overflow() {
+    #[cfg(target_pointer_width = "8")]
+    type Bigger = u16;
+    #[cfg(target_pointer_width = "16")]
+    type Bigger = u32;
+    #[cfg(target_pointer_width = "32")]
+    type Bigger = u64;
+    #[cfg(target_pointer_width = "64")]
+    type Bigger = u128;
+
+    #[derive(Clone)]
+    struct Test(Bigger);
+    impl<'a> Iterator for &'a mut Test {
+        type Item = i32;
+        fn next(&mut self) -> Option<Self::Item> { Some(21) }
+        fn nth(&mut self, n: usize) -> Option<Self::Item> {
+            self.0 += n as Bigger + 1;
+            Some(42)
+        }
+    }
+
+    let mut it = Test(0);
+    let root = usize::MAX >> (::std::mem::size_of::<usize>() * 8 / 2);
+    let n = root + 20;
+    (&mut it).step_by(n).nth(n);
+    assert_eq!(it.0, n as Bigger * n as Bigger);
+
+    // large step
+    let mut it = Test(0);
+    (&mut it).step_by(usize::MAX).nth(5);
+    assert_eq!(it.0, (usize::MAX as Bigger) * 5);
+
+    // n + 1 overflows
+    let mut it = Test(0);
+    (&mut it).step_by(2).nth(usize::MAX);
+    assert_eq!(it.0, (usize::MAX as Bigger) * 2);
+
+    // n + 1 overflows
+    let mut it = Test(0);
+    (&mut it).step_by(1).nth(usize::MAX);
+    assert_eq!(it.0, (usize::MAX as Bigger) * 1);
+}
+
+#[test]
 #[should_panic]
 fn test_iterator_step_by_zero() {
     let mut it = (0..).step_by(0);
diff --git a/src/libpanic_abort/lib.rs b/src/libpanic_abort/lib.rs
index c3bd6a2bc18..5f768ef4399 100644
--- a/src/libpanic_abort/lib.rs
+++ b/src/libpanic_abort/lib.rs
@@ -27,10 +27,12 @@
 #![feature(libc)]
 #![feature(panic_runtime)]
 #![feature(staged_api)]
+#![feature(rustc_attrs)]
 
 // Rust's "try" function, but if we're aborting on panics we just call the
 // function as there's nothing else we need to do here.
 #[no_mangle]
+#[rustc_std_internal_symbol]
 pub unsafe extern fn __rust_maybe_catch_panic(f: fn(*mut u8),
                                               data: *mut u8,
                                               _data_ptr: *mut usize,
@@ -50,6 +52,7 @@ pub unsafe extern fn __rust_maybe_catch_panic(f: fn(*mut u8),
 // will kill us with an illegal instruction, which will do a good enough job for
 // now hopefully.
 #[no_mangle]
+#[rustc_std_internal_symbol]
 pub unsafe extern fn __rust_start_panic(_data: usize, _vtable: usize) -> u32 {
     abort();
 
diff --git a/src/librustc/README.md b/src/librustc/README.md
index ddf71a06d60..722456a76ce 100644
--- a/src/librustc/README.md
+++ b/src/librustc/README.md
@@ -176,6 +176,7 @@ pointers for understanding them better.
 - `'gcx` -- the lifetime of the global arena (see `librustc/ty`).
 - generics -- the set of generic type parameters defined on a type or item
 - ICE -- internal compiler error. When the compiler crashes.
+- ICH -- incremental compilation hash.
 - infcx -- the inference context (see `librustc/infer`)
 - MIR -- the **Mid-level IR** that is created after type-checking for use by borrowck and trans.
   Defined in the `src/librustc/mir/` module, but much of the code that manipulates it is
diff --git a/src/librustc/dep_graph/dep_node.rs b/src/librustc/dep_graph/dep_node.rs
index 1de9091b5df..4034055d041 100644
--- a/src/librustc/dep_graph/dep_node.rs
+++ b/src/librustc/dep_graph/dep_node.rs
@@ -639,6 +639,9 @@ define_dep_nodes!( <'tcx>
     [] TargetFeaturesEnabled(DefId),
 
     [] InstanceDefSizeEstimate { instance_def: InstanceDef<'tcx> },
+
+    [] GetSymbolExportLevel(DefId),
+
 );
 
 trait DepNodeParams<'a, 'gcx: 'tcx + 'a, 'tcx: 'a> : fmt::Debug {
diff --git a/src/librustc/traits/error_reporting.rs b/src/librustc/traits/error_reporting.rs
index 42200a3a447..d65becb912a 100644
--- a/src/librustc/traits/error_reporting.rs
+++ b/src/librustc/traits/error_reporting.rs
@@ -831,6 +831,11 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
                 span,
                 node: hir::ImplItemKind::Method(hir::MethodSig { ref decl, .. }, _),
                 ..
+            }) |
+            hir::map::NodeTraitItem(&hir::TraitItem {
+                span,
+                node: hir::TraitItemKind::Method(hir::MethodSig { ref decl, .. }, _),
+                ..
             }) => {
                 (self.tcx.sess.codemap().def_span(span), decl.inputs.iter()
                         .map(|arg| match arg.clone().into_inner().node {
diff --git a/src/librustc/ty/maps/mod.rs b/src/librustc/ty/maps/mod.rs
index 6c79f6a62fa..85fca68187f 100644
--- a/src/librustc/ty/maps/mod.rs
+++ b/src/librustc/ty/maps/mod.rs
@@ -343,6 +343,7 @@ define_maps! { <'tcx>
         -> (Arc<DefIdSet>, Arc<Vec<Arc<CodegenUnit<'tcx>>>>),
     [] fn export_name: ExportName(DefId) -> Option<Symbol>,
     [] fn contains_extern_indicator: ContainsExternIndicator(DefId) -> bool,
+    [] fn symbol_export_level: GetSymbolExportLevel(DefId) -> SymbolExportLevel,
     [] fn is_translated_function: IsTranslatedFunction(DefId) -> bool,
     [] fn codegen_unit: CodegenUnit(InternedString) -> Arc<CodegenUnit<'tcx>>,
     [] fn compile_codegen_unit: CompileCodegenUnit(InternedString) -> Stats,
diff --git a/src/librustc/ty/maps/plumbing.rs b/src/librustc/ty/maps/plumbing.rs
index c9eebc3d2a0..0ab6ee1a54a 100644
--- a/src/librustc/ty/maps/plumbing.rs
+++ b/src/librustc/ty/maps/plumbing.rs
@@ -921,6 +921,8 @@ pub fn force_from_dep_node<'a, 'gcx, 'lcx>(tcx: TyCtxt<'a, 'gcx, 'lcx>,
 
         DepKind::TargetFeaturesWhitelist => { force!(target_features_whitelist, LOCAL_CRATE); }
         DepKind::TargetFeaturesEnabled => { force!(target_features_enabled, def_id!()); }
+
+        DepKind::GetSymbolExportLevel => { force!(symbol_export_level, def_id!()); }
     }
 
     true
diff --git a/src/librustc_back/target/mod.rs b/src/librustc_back/target/mod.rs
index 3c8a676dcc2..2872c59157d 100644
--- a/src/librustc_back/target/mod.rs
+++ b/src/librustc_back/target/mod.rs
@@ -468,6 +468,10 @@ pub struct TargetOptions {
 
     /// The codegen backend to use for this target, typically "llvm"
     pub codegen_backend: String,
+
+    /// The default visibility for symbols in this target should be "hidden"
+    /// rather than "default"
+    pub default_hidden_visibility: bool,
 }
 
 impl Default for TargetOptions {
@@ -538,6 +542,7 @@ impl Default for TargetOptions {
             no_builtins: false,
             i128_lowering: false,
             codegen_backend: "llvm".to_string(),
+            default_hidden_visibility: false,
         }
     }
 }
@@ -785,6 +790,7 @@ impl Target {
         key!(singlethread, bool);
         key!(no_builtins, bool);
         key!(codegen_backend);
+        key!(default_hidden_visibility, bool);
 
         if let Some(array) = obj.find("abi-blacklist").and_then(Json::as_array) {
             for name in array.iter().filter_map(|abi| abi.as_string()) {
@@ -982,6 +988,7 @@ impl ToJson for Target {
         target_option_val!(singlethread);
         target_option_val!(no_builtins);
         target_option_val!(codegen_backend);
+        target_option_val!(default_hidden_visibility);
 
         if default.abi_blacklist != self.options.abi_blacklist {
             d.insert("abi-blacklist".to_string(), self.options.abi_blacklist.iter()
diff --git a/src/librustc_back/target/msp430_none_elf.rs b/src/librustc_back/target/msp430_none_elf.rs
index 509a7cf5e03..966df897f01 100644
--- a/src/librustc_back/target/msp430_none_elf.rs
+++ b/src/librustc_back/target/msp430_none_elf.rs
@@ -53,6 +53,12 @@ pub fn target() -> TargetResult {
             // don't want to invoke that many gcc instances.
             default_codegen_units: Some(1),
 
+            // Since MSP430 doesn't meaningfully support faulting on illegal
+            // instructions, LLVM generates a call to abort() function instead
+            // of a trap instruction. Such calls are 4 bytes long, and that is
+            // too much overhead for such small target.
+            trap_unreachable: false,
+
             .. Default::default( )
         }
     })
diff --git a/src/librustc_back/target/wasm32_unknown_unknown.rs b/src/librustc_back/target/wasm32_unknown_unknown.rs
index 7e1011ab8af..242860e5c6e 100644
--- a/src/librustc_back/target/wasm32_unknown_unknown.rs
+++ b/src/librustc_back/target/wasm32_unknown_unknown.rs
@@ -83,6 +83,9 @@ pub fn target() -> Result<Target, String> {
         // performing LTO with compiler-builtins.
         no_builtins: true,
 
+        // no dynamic linking, no need for default visibility!
+        default_hidden_visibility: true,
+
         .. Default::default()
     };
     Ok(Target {
diff --git a/src/librustc_const_eval/check_match.rs b/src/librustc_const_eval/check_match.rs
index fd171b89924..ae53ed0e114 100644
--- a/src/librustc_const_eval/check_match.rs
+++ b/src/librustc_const_eval/check_match.rs
@@ -127,13 +127,16 @@ impl<'a, 'tcx> Visitor<'tcx> for MatchVisitor<'a, 'tcx> {
     }
 }
 
+
 impl<'a, 'tcx> PatternContext<'a, 'tcx> {
     fn report_inlining_errors(&self, pat_span: Span) {
         for error in &self.errors {
             match *error {
                 PatternError::StaticInPattern(span) => {
-                    span_err!(self.tcx.sess, span, E0158,
-                              "statics cannot be referenced in patterns");
+                    self.span_e0158(span, "statics cannot be referenced in patterns")
+                }
+                PatternError::AssociatedConstInPattern(span) => {
+                    self.span_e0158(span, "associated consts cannot be referenced in patterns")
                 }
                 PatternError::ConstEval(ref err) => {
                     err.report(self.tcx, pat_span, "pattern");
@@ -141,6 +144,10 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
             }
         }
     }
+
+    fn span_e0158(&self, span: Span, text: &str) {
+        span_err!(self.tcx.sess, span, E0158, "{}", text)
+    }
 }
 
 impl<'a, 'tcx> MatchVisitor<'a, 'tcx> {
diff --git a/src/librustc_const_eval/pattern.rs b/src/librustc_const_eval/pattern.rs
index 3577feaf90c..e0b3929e32a 100644
--- a/src/librustc_const_eval/pattern.rs
+++ b/src/librustc_const_eval/pattern.rs
@@ -27,6 +27,7 @@ use syntax_pos::Span;
 
 #[derive(Clone, Debug)]
 pub enum PatternError<'tcx> {
+    AssociatedConstInPattern(Span),
     StaticInPattern(Span),
     ConstEval(ConstEvalErr<'tcx>),
 }
@@ -635,6 +636,10 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
                   -> Pattern<'tcx> {
         let ty = self.tables.node_id_to_type(id);
         let def = self.tables.qpath_def(qpath, id);
+        let is_associated_const = match def {
+            Def::AssociatedConst(_) => true,
+            _ => false,
+        };
         let kind = match def {
             Def::Const(def_id) | Def::AssociatedConst(def_id) => {
                 let substs = self.tables.node_substs(id);
@@ -656,7 +661,11 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
                         return pat;
                     }
                     None => {
-                        self.errors.push(PatternError::StaticInPattern(span));
+                        self.errors.push(if is_associated_const {
+                            PatternError::AssociatedConstInPattern(span)
+                        } else {
+                            PatternError::StaticInPattern(span)
+                        });
                         PatternKind::Wild
                     }
                 }
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index ada96aaf85c..05dcaf73135 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -290,7 +290,7 @@ fn get_trans_sysroot(backend_name: &str) -> fn() -> Box<TransCrate> {
     let sysroot = sysroot_candidates.iter()
         .map(|sysroot| {
             let libdir = filesearch::relative_target_lib_path(&sysroot, &target);
-            sysroot.join(&libdir).join("codegen-backends")
+            sysroot.join(libdir).with_file_name("codegen-backends")
         })
         .filter(|f| {
             info!("codegen backend candidate: {}", f.display());
@@ -457,10 +457,13 @@ pub fn run_compiler<'a>(args: &[String],
                                            None);
 
     let (odir, ofile) = make_output(&matches);
-    let (input, input_file_path) = match make_input(&matches.free) {
-        Some((input, input_file_path)) => callbacks.some_input(input, input_file_path),
+    let (input, input_file_path, input_err) = match make_input(&matches.free) {
+        Some((input, input_file_path, input_err)) => {
+            let (input, input_file_path) = callbacks.some_input(input, input_file_path);
+            (input, input_file_path, input_err)
+        },
         None => match callbacks.no_input(&matches, &sopts, &cfg, &odir, &ofile, &descriptions) {
-            Some((input, input_file_path)) => (input, input_file_path),
+            Some((input, input_file_path)) => (input, input_file_path, None),
             None => return (Ok(()), None),
         },
     };
@@ -471,6 +474,13 @@ pub fn run_compiler<'a>(args: &[String],
         sopts, input_file_path.clone(), descriptions, codemap, emitter_dest,
     );
 
+    if let Some(err) = input_err {
+        // Immediately stop compilation if there was an issue reading
+        // the input (for example if the input stream is not UTF-8).
+        sess.err(&format!("{}", err));
+        return (Err(CompileIncomplete::Stopped), Some(sess));
+    }
+
     let trans = get_trans(&sess);
 
     rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
@@ -513,17 +523,22 @@ fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>)
 }
 
 // Extract input (string or file and optional path) from matches.
-fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>)> {
+fn make_input(free_matches: &[String]) -> Option<(Input, Option<PathBuf>, Option<io::Error>)> {
     if free_matches.len() == 1 {
         let ifile = &free_matches[0];
         if ifile == "-" {
             let mut src = String::new();
-            io::stdin().read_to_string(&mut src).unwrap();
+            let err = if io::stdin().read_to_string(&mut src).is_err() {
+                Some(io::Error::new(io::ErrorKind::InvalidData,
+                                    "couldn't read from stdin, as it did not contain valid UTF-8"))
+            } else {
+                None
+            };
             Some((Input::Str { name: FileName::Anon, input: src },
-                  None))
+                  None, err))
         } else {
             Some((Input::File(PathBuf::from(ifile)),
-                  Some(PathBuf::from(ifile))))
+                  Some(PathBuf::from(ifile)), None))
         }
     } else {
         None
diff --git a/src/librustc_errors/emitter.rs b/src/librustc_errors/emitter.rs
index a59f68a6442..a49284eb55a 100644
--- a/src/librustc_errors/emitter.rs
+++ b/src/librustc_errors/emitter.rs
@@ -290,6 +290,10 @@ impl EmitterWriter {
                           line: &Line,
                           width_offset: usize,
                           code_offset: usize) -> Vec<(usize, Style)> {
+        if line.line_index == 0 {
+            return Vec::new();
+        }
+
         let source_string = match file.get_line(line.line_index - 1) {
             Some(s) => s,
             None => return Vec::new(),
diff --git a/src/librustc_mir/monomorphize/partitioning.rs b/src/librustc_mir/monomorphize/partitioning.rs
index 806d787c845..e9471cdb4f9 100644
--- a/src/librustc_mir/monomorphize/partitioning.rs
+++ b/src/librustc_mir/monomorphize/partitioning.rs
@@ -107,6 +107,7 @@ use rustc::dep_graph::WorkProductId;
 use rustc::hir::def_id::DefId;
 use rustc::hir::map::DefPathData;
 use rustc::mir::mono::{Linkage, Visibility};
+use rustc::middle::exported_symbols::SymbolExportLevel;
 use rustc::ty::{self, TyCtxt, InstanceDef};
 use rustc::ty::item_path::characteristic_def_id_of_type;
 use rustc::util::nodemap::{FxHashMap, FxHashSet};
@@ -322,7 +323,16 @@ fn place_root_translation_items<'a, 'tcx, I>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                                             .or_insert_with(make_codegen_unit);
 
         let mut can_be_internalized = true;
-        let (linkage, visibility) = match trans_item.explicit_linkage(tcx) {
+        let default_visibility = |id: DefId| {
+            if tcx.sess.target.target.options.default_hidden_visibility &&
+                tcx.symbol_export_level(id) != SymbolExportLevel::C
+            {
+                Visibility::Hidden
+            } else {
+                Visibility::Default
+            }
+        };
+        let (linkage, mut visibility) = match trans_item.explicit_linkage(tcx) {
             Some(explicit_linkage) => (explicit_linkage, Visibility::Default),
             None => {
                 match trans_item {
@@ -352,7 +362,8 @@ fn place_root_translation_items<'a, 'tcx, I>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                                     Visibility::Hidden
                                 } else if def_id.is_local() {
                                     if tcx.is_exported_symbol(def_id) {
-                                        Visibility::Default
+                                        can_be_internalized = false;
+                                        default_visibility(def_id)
                                     } else {
                                         Visibility::Hidden
                                     }
@@ -375,7 +386,8 @@ fn place_root_translation_items<'a, 'tcx, I>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                     MonoItem::GlobalAsm(node_id) => {
                         let def_id = tcx.hir.local_def_id(node_id);
                         let visibility = if tcx.is_exported_symbol(def_id) {
-                            Visibility::Default
+                            can_be_internalized = false;
+                            default_visibility(def_id)
                         } else {
                             Visibility::Hidden
                         };
diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index ecf3c9e42d5..2da4bfedd3a 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -3998,14 +3998,20 @@ impl<'a> Resolver<'a> {
 
             if let (Ok(snippet), false) = (cm.span_to_snippet(binding.span),
                                            binding.is_renamed_extern_crate()) {
+                let suggested_name = if name.as_str().chars().next().unwrap().is_uppercase() {
+                    format!("Other{}", name)
+                } else {
+                    format!("other_{}", name)
+                };
+
                 err.span_suggestion(binding.span,
                                     rename_msg,
                                     if snippet.ends_with(';') {
-                                        format!("{} as Other{};",
+                                        format!("{} as {};",
                                                 &snippet[..snippet.len()-1],
-                                                name)
+                                                suggested_name)
                                     } else {
-                                        format!("{} as Other{}", snippet, name)
+                                        format!("{} as {}", snippet, suggested_name)
                                     });
             } else {
                 err.span_label(binding.span, rename_msg);
diff --git a/src/librustc_trans/allocator.rs b/src/librustc_trans/allocator.rs
index fd5aa1364d3..e1c145b122d 100644
--- a/src/librustc_trans/allocator.rs
+++ b/src/librustc_trans/allocator.rs
@@ -86,6 +86,10 @@ pub(crate) unsafe fn trans(tcx: TyCtxt, mods: &ModuleLlvm, kind: AllocatorKind)
                                                      name.as_ptr(),
                                                      ty);
 
+        if tcx.sess.target.target.options.default_hidden_visibility {
+            llvm::LLVMRustSetVisibility(llfn, llvm::Visibility::Hidden);
+        }
+
         let callee = CString::new(kind.fn_name(method.name)).unwrap();
         let callee = llvm::LLVMRustGetOrInsertFunction(llmod,
                                                        callee.as_ptr(),
diff --git a/src/librustc_trans/asm.rs b/src/librustc_trans/asm.rs
index c7be0c4e67d..751f8148a2a 100644
--- a/src/librustc_trans/asm.rs
+++ b/src/librustc_trans/asm.rs
@@ -59,8 +59,9 @@ pub fn trans_inline_asm<'a, 'tcx>(
     // Default per-arch clobbers
     // Basically what clang does
     let arch_clobbers = match &bx.sess().target.target.arch[..] {
-        "x86" | "x86_64" => vec!["~{dirflag}", "~{fpsr}", "~{flags}"],
-        _                => Vec::new()
+        "x86" | "x86_64"  => vec!["~{dirflag}", "~{fpsr}", "~{flags}"],
+        "mips" | "mips64" => vec!["~{$1}"],
+        _                 => Vec::new()
     };
 
     let all_constraints =
diff --git a/src/librustc_trans/back/symbol_export.rs b/src/librustc_trans/back/symbol_export.rs
index 15ff59c7df9..989ef8a9537 100644
--- a/src/librustc_trans/back/symbol_export.rs
+++ b/src/librustc_trans/back/symbol_export.rs
@@ -133,6 +133,8 @@ pub fn provide(providers: &mut Providers) {
 
         Arc::new(local_crate)
     };
+
+    providers.symbol_export_level = export_level;
 }
 
 pub fn provide_extern(providers: &mut Providers) {
@@ -203,6 +205,7 @@ pub fn provide_extern(providers: &mut Providers) {
 
         Arc::new(crate_exports)
     };
+    providers.symbol_export_level = export_level;
 }
 
 fn export_level(tcx: TyCtxt, sym_def_id: DefId) -> SymbolExportLevel {
diff --git a/src/librustc_trans/type_of.rs b/src/librustc_trans/type_of.rs
index b1533cfad19..af957500f70 100644
--- a/src/librustc_trans/type_of.rs
+++ b/src/librustc_trans/type_of.rs
@@ -57,7 +57,9 @@ fn uncached_llvm_type<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
         ty::TyClosure(..) |
         ty::TyGenerator(..) |
         ty::TyAdt(..) |
-        ty::TyDynamic(..) |
+        // FIXME(eddyb) producing readable type names for trait objects can result
+        // in problematically distinct types due to HRTB and subtyping (see #47638).
+        // ty::TyDynamic(..) |
         ty::TyForeign(..) |
         ty::TyStr => {
             let mut name = String::with_capacity(32);
diff --git a/src/libstd/io/error.rs b/src/libstd/io/error.rs
index f0b41f30251..bdd675e6e2b 100644
--- a/src/libstd/io/error.rs
+++ b/src/libstd/io/error.rs
@@ -292,8 +292,8 @@ impl Error {
     /// # if cfg!(target_os = "linux") {
     /// use std::io;
     ///
-    /// let error = io::Error::from_raw_os_error(98);
-    /// assert_eq!(error.kind(), io::ErrorKind::AddrInUse);
+    /// let error = io::Error::from_raw_os_error(22);
+    /// assert_eq!(error.kind(), io::ErrorKind::InvalidInput);
     /// # }
     /// ```
     ///
@@ -303,8 +303,8 @@ impl Error {
     /// # if cfg!(windows) {
     /// use std::io;
     ///
-    /// let error = io::Error::from_raw_os_error(10048);
-    /// assert_eq!(error.kind(), io::ErrorKind::AddrInUse);
+    /// let error = io::Error::from_raw_os_error(10022);
+    /// assert_eq!(error.kind(), io::ErrorKind::InvalidInput);
     /// # }
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
diff --git a/src/rustllvm/PassWrapper.cpp b/src/rustllvm/PassWrapper.cpp
index b2f1229891d..06d1301d700 100644
--- a/src/rustllvm/PassWrapper.cpp
+++ b/src/rustllvm/PassWrapper.cpp
@@ -836,6 +836,10 @@ struct LLVMRustThinLTOData {
   StringMap<FunctionImporter::ImportMapTy> ImportLists;
   StringMap<FunctionImporter::ExportSetTy> ExportLists;
   StringMap<GVSummaryMapTy> ModuleToDefinedGVSummaries;
+
+#if LLVM_VERSION_GE(7, 0)
+  LLVMRustThinLTOData() : Index(/* isPerformingAnalysis = */ false) {}
+#endif
 };
 
 // Just an argument to the `LLVMRustCreateThinLTOData` function below.
@@ -918,7 +922,14 @@ LLVMRustCreateThinLTOData(LLVMRustThinLTOModule *modules,
   //
   // This is copied from `lib/LTO/ThinLTOCodeGenerator.cpp`
 #if LLVM_VERSION_GE(5, 0)
+#if LLVM_VERSION_GE(7, 0)
+  auto deadIsPrevailing = [&](GlobalValue::GUID G) {
+    return PrevailingType::Unknown;
+  };
+  computeDeadSymbols(Ret->Index, Ret->GUIDPreservedSymbols, deadIsPrevailing);
+#else
   computeDeadSymbols(Ret->Index, Ret->GUIDPreservedSymbols);
+#endif
   ComputeCrossModuleImport(
     Ret->Index,
     Ret->ModuleToDefinedGVSummaries,
diff --git a/src/test/codegen/function-arguments.rs b/src/test/codegen/function-arguments.rs
index f8945a6ee8d..0e98d3f9050 100644
--- a/src/test/codegen/function-arguments.rs
+++ b/src/test/codegen/function-arguments.rs
@@ -122,13 +122,13 @@ pub fn unsafe_slice(_: &[UnsafeInner]) {
 pub fn str(_: &[u8]) {
 }
 
-// CHECK: @trait_borrow(%"core::ops::drop::Drop"* nonnull %arg0.0, {}* noalias nonnull readonly %arg0.1)
+// CHECK: @trait_borrow({}* nonnull %arg0.0, {}* noalias nonnull readonly %arg0.1)
 // FIXME #25759 This should also have `nocapture`
 #[no_mangle]
 pub fn trait_borrow(_: &Drop) {
 }
 
-// CHECK: @trait_box(%"core::ops::drop::Drop"* noalias nonnull, {}* noalias nonnull readonly)
+// CHECK: @trait_box({}* noalias nonnull, {}* noalias nonnull readonly)
 #[no_mangle]
 pub fn trait_box(_: Box<Drop>) {
 }
diff --git a/src/test/compile-fail/associated-const-type-parameter-arms.rs b/src/test/compile-fail/associated-const-type-parameter-arms.rs
index 52bb4a1b463..630a234fa66 100644
--- a/src/test/compile-fail/associated-const-type-parameter-arms.rs
+++ b/src/test/compile-fail/associated-const-type-parameter-arms.rs
@@ -16,6 +16,7 @@ pub trait Foo {
 }
 
 struct Abc;
+
 impl Foo for Abc {
     const X: EFoo = EFoo::B;
 }
@@ -27,8 +28,10 @@ impl Foo for Def {
 
 pub fn test<A: Foo, B: Foo>(arg: EFoo) {
     match arg {
-        A::X => println!("A::X"), //~ error: statics cannot be referenced in patterns [E0158]
-        B::X => println!("B::X"), //~ error: statics cannot be referenced in patterns [E0158]
+        A::X => println!("A::X"),
+        //~^ error: associated consts cannot be referenced in patterns [E0158]
+        B::X => println!("B::X"),
+        //~^ error: associated consts cannot be referenced in patterns [E0158]
         _ => (),
     }
 }
diff --git a/src/test/run-make/stdin-non-utf8/Makefile b/src/test/run-make/stdin-non-utf8/Makefile
new file mode 100644
index 00000000000..7948c442616
--- /dev/null
+++ b/src/test/run-make/stdin-non-utf8/Makefile
@@ -0,0 +1,6 @@
+-include ../tools.mk
+
+all:
+	cp non-utf8 $(TMPDIR)/non-utf.rs
+	cat $(TMPDIR)/non-utf.rs | $(RUSTC) - 2>&1 \
+		| $(CGREP) "error: couldn't read from stdin, as it did not contain valid UTF-8"
diff --git a/src/test/run-make/stdin-non-utf8/non-utf8 b/src/test/run-make/stdin-non-utf8/non-utf8
new file mode 100644
index 00000000000..bc87051a852
--- /dev/null
+++ b/src/test/run-make/stdin-non-utf8/non-utf8
@@ -0,0 +1 @@
+Ò
diff --git a/src/test/run-pass/issue-47638.rs b/src/test/run-pass/issue-47638.rs
new file mode 100644
index 00000000000..6f627b2a3c1
--- /dev/null
+++ b/src/test/run-pass/issue-47638.rs
@@ -0,0 +1,18 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+fn id<'c, 'b>(f: &'c &'b Fn(&i32)) -> &'c &'b Fn(&'static i32) {
+    f
+}
+
+fn main() {
+    let f: &Fn(&i32) = &|x| {};
+    id(&f);
+}
diff --git a/src/test/run-pass/sse2.rs b/src/test/run-pass/sse2.rs
index c2414e5ff5d..22469b2fde0 100644
--- a/src/test/run-pass/sse2.rs
+++ b/src/test/run-pass/sse2.rs
@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// min-llvm-version 4.0
+// no-system-llvm -- needs MCSubtargetInfo::getFeatureTable()
 // ignore-cloudabi no std::env
 
 #![feature(cfg_target_feature)]
diff --git a/src/test/ui/blind-item-item-shadow.stderr b/src/test/ui/blind-item-item-shadow.stderr
index 855b3799eb5..d3588be2669 100644
--- a/src/test/ui/blind-item-item-shadow.stderr
+++ b/src/test/ui/blind-item-item-shadow.stderr
@@ -10,8 +10,8 @@ error[E0255]: the name `foo` is defined multiple times
    = note: `foo` must be defined only once in the type namespace of this module
 help: You can use `as` to change the binding name of the import
    |
-13 | use foo::foo as Otherfoo;
-   |     ^^^^^^^^^^^^^^^^^^^^
+13 | use foo::foo as other_foo;
+   |     ^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/double-import.stderr b/src/test/ui/double-import.stderr
index fcd3f2696f2..2a0f9ee34f2 100644
--- a/src/test/ui/double-import.stderr
+++ b/src/test/ui/double-import.stderr
@@ -9,8 +9,8 @@ error[E0252]: the name `foo` is defined multiple times
    = note: `foo` must be defined only once in the value namespace of this module
 help: You can use `as` to change the binding name of the import
    |
-23 | use sub2::foo as Otherfoo; //~ ERROR the name `foo` is defined multiple times
-   |     ^^^^^^^^^^^^^^^^^^^^^
+23 | use sub2::foo as other_foo; //~ ERROR the name `foo` is defined multiple times
+   |     ^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/imports/duplicate.stderr b/src/test/ui/imports/duplicate.stderr
index a74401314a1..6e5b91a11c9 100644
--- a/src/test/ui/imports/duplicate.stderr
+++ b/src/test/ui/imports/duplicate.stderr
@@ -9,8 +9,8 @@ error[E0252]: the name `foo` is defined multiple times
    = note: `foo` must be defined only once in the value namespace of this module
 help: You can use `as` to change the binding name of the import
    |
-25 |     use a::foo as Otherfoo; //~ ERROR the name `foo` is defined multiple times
-   |         ^^^^^^^^^^^^^^^^^^
+25 |     use a::foo as other_foo; //~ ERROR the name `foo` is defined multiple times
+   |         ^^^^^^^^^^^^^^^^^^^
 
 error[E0659]: `foo` is ambiguous
   --> $DIR/duplicate.rs:56:9
diff --git a/src/test/ui/issue-26886.stderr b/src/test/ui/issue-26886.stderr
index cb2eca87068..e6424e535ee 100644
--- a/src/test/ui/issue-26886.stderr
+++ b/src/test/ui/issue-26886.stderr
@@ -24,8 +24,8 @@ error[E0252]: the name `sync` is defined multiple times
    = note: `sync` must be defined only once in the type namespace of this module
 help: You can use `as` to change the binding name of the import
    |
-14 | use std::sync as Othersync; //~ ERROR the name `sync` is defined multiple times
-   |     ^^^^^^^^^^^^^^^^^^^^^^
+14 | use std::sync as other_sync; //~ ERROR the name `sync` is defined multiple times
+   |     ^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/issue-47706-trait.rs b/src/test/ui/issue-47706-trait.rs
new file mode 100644
index 00000000000..86a9da49a05
--- /dev/null
+++ b/src/test/ui/issue-47706-trait.rs
@@ -0,0 +1,16 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+trait T {
+    fn f(&self, _: ()) {
+        None::<()>.map(Self::f);
+    }
+    //~^^ ERROR function is expected to take a single 0-tuple as argument
+}
diff --git a/src/test/ui/issue-47706-trait.stderr b/src/test/ui/issue-47706-trait.stderr
new file mode 100644
index 00000000000..320e98dee4a
--- /dev/null
+++ b/src/test/ui/issue-47706-trait.stderr
@@ -0,0 +1,12 @@
+error[E0601]: main function not found
+
+error[E0593]: function is expected to take a single 0-tuple as argument, but it takes 2 distinct arguments
+  --> $DIR/issue-47706-trait.rs:13:20
+   |
+12 |     fn f(&self, _: ()) {
+   |     ------------------ takes 2 distinct arguments
+13 |         None::<()>.map(Self::f);
+   |                    ^^^ expected function that takes a single 0-tuple as argument
+
+error: aborting due to 2 previous errors
+
diff --git a/src/test/ui/resolve-conflict-item-vs-import.stderr b/src/test/ui/resolve-conflict-item-vs-import.stderr
index 03ef66681e4..e2245b8a8b1 100644
--- a/src/test/ui/resolve-conflict-item-vs-import.stderr
+++ b/src/test/ui/resolve-conflict-item-vs-import.stderr
@@ -10,8 +10,8 @@ error[E0255]: the name `transmute` is defined multiple times
    = note: `transmute` must be defined only once in the value namespace of this module
 help: You can use `as` to change the binding name of the import
    |
-11 | use std::mem::transmute as Othertransmute;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+11 | use std::mem::transmute as other_transmute;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/suggestions/issue-45799-bad-extern-crate-rename-suggestion-formatting.stderr b/src/test/ui/suggestions/issue-45799-bad-extern-crate-rename-suggestion-formatting.stderr
index d2ac15f7ffc..01dba62a851 100644
--- a/src/test/ui/suggestions/issue-45799-bad-extern-crate-rename-suggestion-formatting.stderr
+++ b/src/test/ui/suggestions/issue-45799-bad-extern-crate-rename-suggestion-formatting.stderr
@@ -7,7 +7,7 @@ error[E0259]: the name `std` is defined multiple times
    = note: `std` must be defined only once in the type namespace of this module
 help: You can use `as` to change the binding name of the import
    |
-11 | extern crate std as Otherstd;
+11 | extern crate std as other_std;
    |
 
 error: aborting due to previous error
diff --git a/src/test/ui/use-mod.stderr b/src/test/ui/use-mod.stderr
index bb64909e64a..1c9f306f493 100644
--- a/src/test/ui/use-mod.stderr
+++ b/src/test/ui/use-mod.stderr
@@ -25,7 +25,7 @@ error[E0252]: the name `bar` is defined multiple times
    = note: `bar` must be defined only once in the type namespace of this module
 help: You can use `as` to change the binding name of the import
    |
-15 |     self as Otherbar
+15 |     self as other_bar
    |
 
 error: aborting due to 3 previous errors