Auto merge of #35747 - jonathandturner:rollup, r=jonathandturner

Rollup of 23 pull requests

- Successful merges: #34370, #35415, #35595, #35610, #35613, #35614, #35621, #35660, #35663, #35670, #35671, #35672, #35681, #35686, #35690, #35695, #35707, #35708, #35713, #35722, #35725, #35726, #35731
- Failed merges: #35395

mk/main.mk

@@ -13,7 +13,7 @@
 ######################################################################
 
 # The version number
-CFG_RELEASE_NUM=1.12.0
+CFG_RELEASE_NUM=1.13.0
 
 # An optional number to put after the label, e.g. '.2' -> '-beta.2'
 # NB Make sure it starts with a dot to conform to semver pre-release

src/doc/book/associated-types.md

@@ -67,7 +67,7 @@ trait Graph {
 Simple enough. Associated types use the `type` keyword, and go inside the body
 of the trait, with the functions.
 
-These `type` declarations can have all the same thing as functions do. For example,
+These type declarations work the same way as those for functions. For example,
 if we wanted our `N` type to implement `Display`, so we can print the nodes out,
 we could do this:
 

src/doc/book/closures.md

@@ -262,7 +262,7 @@ the result:
 
 ```rust
 fn call_with_one<F>(some_closure: F) -> i32
-    where F : Fn(i32) -> i32 {
+    where F: Fn(i32) -> i32 {
 
     some_closure(1)
 }
@@ -279,7 +279,7 @@ Let’s examine the signature of `call_with_one` in more depth:
 
 ```rust
 fn call_with_one<F>(some_closure: F) -> i32
-#    where F : Fn(i32) -> i32 {
+#    where F: Fn(i32) -> i32 {
 #    some_closure(1) }
 ```
 
@@ -288,7 +288,7 @@ isn’t interesting. The next part is:
 
 ```rust
 # fn call_with_one<F>(some_closure: F) -> i32
-    where F : Fn(i32) -> i32 {
+    where F: Fn(i32) -> i32 {
 #   some_closure(1) }
 ```
 

src/doc/book/lang-items.md

@@ -57,8 +57,8 @@ fn main(argc: isize, argv: *const *const u8) -> isize {
     0
 }
 
-#[lang = "eh_personality"] extern fn eh_personality() {}
-#[lang = "panic_fmt"] fn panic_fmt() -> ! { loop {} }
+#[lang = "eh_personality"] extern fn rust_eh_personality() {}
+#[lang = "panic_fmt"] extern fn rust_begin_panic() -> ! { loop {} }
 # #[lang = "eh_unwind_resume"] extern fn rust_eh_unwind_resume() {}
 # #[no_mangle] pub extern fn rust_eh_register_frames () {}
 # #[no_mangle] pub extern fn rust_eh_unregister_frames () {}
@@ -73,8 +73,8 @@ Other features provided by lang items include:
   `==`, `<`, dereferencing (`*`) and `+` (etc.) operators are all
   marked with lang items; those specific four are `eq`, `ord`,
   `deref`, and `add` respectively.
-- stack unwinding and general failure; the `eh_personality`, `fail`
-  and `fail_bounds_checks` lang items.
+- stack unwinding and general failure; the `eh_personality`,
+  `eh_unwind_resume`, `fail` and `fail_bounds_checks` lang items.
 - the traits in `std::marker` used to indicate types of
   various kinds; lang items `send`, `sync` and `copy`.
 - the marker types and variance indicators found in

src/doc/book/no-stdlib.md

@@ -55,7 +55,13 @@ fn start(_argc: isize, _argv: *const *const u8) -> isize {
 // provided by libstd.
 #[lang = "eh_personality"]
 #[no_mangle]
-pub extern fn eh_personality() {
+pub extern fn rust_eh_personality() {
+}
+
+// This function may be needed based on the compilation target.
+#[lang = "eh_unwind_resume"]
+#[no_mangle]
+pub extern fn rust_eh_unwind_resume() {
 }
 
 #[lang = "panic_fmt"]
@@ -87,12 +93,18 @@ pub extern fn main(_argc: i32, _argv: *const *const u8) -> i32 {
     0
 }
 
-// These functions and traits are used by the compiler, but not
+// These functions are used by the compiler, but not
 // for a bare-bones hello world. These are normally
 // provided by libstd.
 #[lang = "eh_personality"]
 #[no_mangle]
-pub extern fn eh_personality() {
+pub extern fn rust_eh_personality() {
+}
+
+// This function may be needed based on the compilation target.
+#[lang = "eh_unwind_resume"]
+#[no_mangle]
+pub extern fn rust_eh_unwind_resume() {
 }
 
 #[lang = "panic_fmt"]
@@ -104,23 +116,28 @@ pub extern fn rust_begin_panic(_msg: core::fmt::Arguments,
 }
 ```
 
-## More about the langauge items
+## More about the language items
 
 The compiler currently makes a few assumptions about symbols which are
 available in the executable to call. Normally these functions are provided by
 the standard library, but without it you must define your own. These symbols
 are called "language items", and they each have an internal name, and then a
 signature that an implementation must conform to.
 
-The first of these two functions, `eh_personality`, is used by the failure
+The first of these functions, `rust_eh_personality`, is used by the failure
 mechanisms of the compiler. This is often mapped to GCC's personality function
 (see the [libstd implementation][unwind] for more information), but crates
 which do not trigger a panic can be assured that this function is never
-called. Both the language item and the symbol name are `eh_personality`.
- 
+called. The language item's name is `eh_personality`.
+
 [unwind]: https://github.com/rust-lang/rust/blob/master/src/libpanic_unwind/gcc.rs
 
-The second function, `panic_fmt`, is also used by the failure mechanisms of the
+The second function, `rust_begin_panic`, is also used by the failure mechanisms of the
 compiler. When a panic happens, this controls the message that's displayed on
 the screen. While the language item's name is `panic_fmt`, the symbol name is
 `rust_begin_panic`.
+
+A third function, `rust_eh_unwind_resume`, is also needed if the `custom_unwind_resume`
+flag is set in the options of the compilation target. It allows customizing the
+process of resuming unwind at the end of the landing pads. The language item's name
+is `eh_unwind_resume`.

src/doc/grammar.md

@@ -172,6 +172,11 @@ token : simple_token | ident | literal | symbol | whitespace token ;
 Each of these keywords has special meaning in its grammar, and all of them are
 excluded from the `ident` rule.
 
+Not all of these keywords are used by the language. Some of them were used
+before Rust 1.0, and were left reserved once their implementations were
+removed. Some of them were reserved before 1.0 to make space for possible
+future features.
+
 ### Literals
 
 ```antlr

src/libcollections/vec.rs

@@ -1715,6 +1715,15 @@ pub struct IntoIter<T> {
     end: *const T,
 }
 
+#[stable(feature = "vec_intoiter_debug", since = "")]
+impl<T: fmt::Debug> fmt::Debug for IntoIter<T> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_tuple("IntoIter")
+            .field(&self.as_slice())
+            .finish()
+    }
+}
+
 impl<T> IntoIter<T> {
     /// Returns the remaining items of this iterator as a slice.
     ///

src/libcollectionstest/vec.rs

@@ -501,6 +501,14 @@ fn test_into_iter_as_mut_slice() {
     assert_eq!(into_iter.as_slice(), &['y', 'c']);
 }
 
+#[test]
+fn test_into_iter_debug() {
+    let vec = vec!['a', 'b', 'c'];
+    let into_iter = vec.into_iter();
+    let debug = format!("{:?}", into_iter);
+    assert_eq!(debug, "IntoIter(['a', 'b', 'c'])");
+}
+
 #[test]
 fn test_into_iter_count() {
     assert_eq!(vec![1, 2, 3].into_iter().count(), 3);

src/libcore/iter/range.rs

@@ -295,20 +295,8 @@ impl<A: Step> ops::Range<A> {
     ///
     /// ```
     /// #![feature(step_by)]
-    ///
-    /// for i in (0..10).step_by(2) {
-    ///     println!("{}", i);
-    /// }
-    /// ```
-    ///
-    /// This prints:
-    ///
-    /// ```text
-    /// 0
-    /// 2
-    /// 4
-    /// 6
-    /// 8
+    /// let result: Vec<_> = (0..10).step_by(2).collect();
+    /// assert_eq!(result, vec![0, 2, 4, 6, 8]);
     /// ```
     #[unstable(feature = "step_by", reason = "recent addition",
                issue = "27741")]
@@ -650,4 +638,3 @@ impl<A: Step> DoubleEndedIterator for ops::RangeInclusive<A> where
         n
     }
 }
-

src/libcore/lib.rs

@@ -42,6 +42,11 @@
 //!   line. It is up to consumers of this core library to define this panic
 //!   function; it is only required to never return. This requires a `lang`
 //!   attribute named `panic_fmt`.
+//!
+//! * `rust_eh_personality` - is used by the failure mechanisms of the
+//!    compiler. This is often mapped to GCC's personality function, but crates
+//!    which do not trigger a panic can be assured that this function is never
+//!    called. The `lang` attribute is called `eh_personality`.
 
 // Since libcore defines many fundamental lang items, all tests live in a
 // separate crate, libcoretest, to avoid bizarre issues.

src/libcore/ops.rs

@@ -10,11 +10,16 @@
 
 //! Overloadable operators.
 //!
-//! Implementing these traits allows you to get an effect similar to
-//! overloading operators.
+//! Implementing these traits allows you to overload certain operators.
 //!
 //! Some of these traits are imported by the prelude, so they are available in
-//! every Rust program.
+//! every Rust program. Only operators backed by traits can be overloaded. For
+//! example, the addition operator (`+`) can be overloaded through the `Add`
+//! trait, but since the assignment operator (`=`) has no backing trait, there
+//! is no way of overloading its semantics. Additionally, this module does not
+//! provide any mechanism to create new operators. If traitless overloading or
+//! custom operators are required, you should look toward macros or compiler
+//! plugins to extend Rust's syntax.
 //!
 //! Many of the operators take their operands by value. In non-generic
 //! contexts involving built-in types, this is usually not a problem.

src/librustc_const_eval/check_match.rs

@@ -1073,11 +1073,12 @@ fn check_irrefutable(cx: &MatchCheckCtxt, pat: &Pat, is_fn_arg: bool) {
     };
 
     is_refutable(cx, pat, |uncovered_pat| {
-        span_err!(cx.tcx.sess, pat.span, E0005,
+        let pattern_string = pat_to_string(uncovered_pat);
+        struct_span_err!(cx.tcx.sess, pat.span, E0005,
             "refutable pattern in {}: `{}` not covered",
             origin,
-            pat_to_string(uncovered_pat),
-        );
+            pattern_string,
+        ).span_label(pat.span, &format!("pattern `{}` not covered", pattern_string)).emit();
     });
 }
 

src/librustc_mir/transform/qualify_consts.rs

@@ -277,7 +277,10 @@ impl<'a, 'tcx> Qualifier<'a, 'tcx, 'tcx> {
             } else {
                 "cannot refer to statics by value, use a constant instead"
             };
-            span_err!(self.tcx.sess, self.span, E0394, "{}", msg);
+            struct_span_err!(self.tcx.sess, self.span, E0394, "{}", msg)
+                .span_label(self.span, &format!("referring to another static by value"))
+                .note(&format!("use the address-of operator or a constant instead"))
+                .emit();
 
             // Replace STATIC with NOT_CONST to avoid further errors.
             self.qualif = self.qualif - Qualif::STATIC;

src/librustc_passes/consts.rs

@@ -283,10 +283,10 @@ impl<'a, 'tcx, 'v> Visitor<'v> for CheckCrateVisitor<'a, 'tcx> {
                     Ok(Ordering::Less) |
                     Ok(Ordering::Equal) => {}
                     Ok(Ordering::Greater) => {
-                        span_err!(self.tcx.sess,
-                                  start.span,
-                                  E0030,
-                                  "lower range bound must be less than or equal to upper");
+                        struct_span_err!(self.tcx.sess, start.span, E0030,
+                            "lower range bound must be less than or equal to upper")
+                            .span_label(start.span, &format!("lower bound larger than upper bound"))
+                            .emit();
                     }
                     Err(ErrorReported) => {}
                 }

src/librustc_resolve/lib.rs

@@ -116,7 +116,7 @@ enum ResolutionError<'a> {
     /// error E0408: variable `{}` from pattern #{} is not bound in pattern #{}
     VariableNotBoundInPattern(Name, usize, usize),
     /// error E0409: variable is bound with different mode in pattern #{} than in pattern #1
-    VariableBoundWithDifferentMode(Name, usize),
+    VariableBoundWithDifferentMode(Name, usize, Span),
     /// error E0411: use of `Self` outside of an impl or trait
     SelfUsedOutsideImplOrTrait,
     /// error E0412: use of undeclared
@@ -269,14 +269,19 @@ fn resolve_struct_error<'b, 'a: 'b, 'c>(resolver: &'b Resolver<'a>,
                              from,
                              to)
         }
-        ResolutionError::VariableBoundWithDifferentMode(variable_name, pattern_number) => {
-            struct_span_err!(resolver.session,
+        ResolutionError::VariableBoundWithDifferentMode(variable_name,
+                                                        pattern_number,
+                                                        first_binding_span) => {
+            let mut err = struct_span_err!(resolver.session,
                              span,
                              E0409,
                              "variable `{}` is bound with different mode in pattern #{} than in \
                               pattern #1",
                              variable_name,
-                             pattern_number)
+                             pattern_number);
+            err.span_label(span, &format!("bound in different ways"));
+            err.span_label(first_binding_span, &format!("first binding"));
+            err
         }
         ResolutionError::SelfUsedOutsideImplOrTrait => {
             let mut err = struct_span_err!(resolver.session,
@@ -316,11 +321,13 @@ fn resolve_struct_error<'b, 'a: 'b, 'c>(resolver: &'b Resolver<'a>,
             err
         }
         ResolutionError::DoesNotNameAStruct(name) => {
-            struct_span_err!(resolver.session,
+            let mut err = struct_span_err!(resolver.session,
                              span,
                              E0422,
                              "`{}` does not name a structure",
-                             name)
+                             name);
+            err.span_label(span, &format!("not a structure"));
+            err
         }
         ResolutionError::StructVariantUsedAsFunction(path_name) => {
             struct_span_err!(resolver.session,
@@ -2028,8 +2035,10 @@ impl<'a> Resolver<'a> {
                         if binding_0.binding_mode != binding_i.binding_mode {
                             resolve_error(self,
                                           binding_i.span,
-                                          ResolutionError::VariableBoundWithDifferentMode(key.name,
-                                                                                          i + 1));
+                                          ResolutionError::VariableBoundWithDifferentMode(
+                                              key.name,
+                                              i + 1,
+                                              binding_0.span));
                         }
                     }
                 }

src/librustc_resolve/resolve_imports.rs

@@ -584,12 +584,12 @@ impl<'a, 'b:'a> ImportResolver<'a, 'b> {
                                        source);
                     self.session.add_lint(PRIVATE_IN_PUBLIC, directive.id, directive.span, msg);
                 } else {
-                    let msg = format!("`{}` is private, and cannot be reexported", source);
-                    let note_msg =
-                        format!("consider declaring type or module `{}` with `pub`", source);
-                    struct_span_err!(self.session, directive.span, E0365, "{}", &msg)
-                        .span_note(directive.span, &note_msg)
-                        .emit();
+                    let mut err = struct_span_err!(self.session, directive.span, E0365,
+                                                     "`{}` is private, and cannot be reexported",
+                                                     source);
+                    err.span_label(directive.span, &format!("reexport of private `{}`", source));
+                    err.note(&format!("consider declaring type or module `{}` with `pub`", source));
+                    err.emit();
                 }
             }
 

src/librustc_typeck/check/wfcheck.rs

@@ -624,8 +624,10 @@ fn error_380(ccx: &CrateCtxt, span: Span) {
 
 fn error_392<'a, 'tcx>(ccx: &CrateCtxt<'a, 'tcx>, span: Span, param_name: ast::Name)
                        -> DiagnosticBuilder<'tcx> {
-    struct_span_err!(ccx.tcx.sess, span, E0392,
-                     "parameter `{}` is never used", param_name)
+    let mut err = struct_span_err!(ccx.tcx.sess, span, E0392,
+                  "parameter `{}` is never used", param_name);
+    err.span_label(span, &format!("unused type parameter"));
+    err
 }
 
 fn error_194(tcx: TyCtxt, span: Span, name: ast::Name) {