Rollup of 7 pull requests

src/libcore/num/f32.rs

@@ -367,7 +367,7 @@ impl f32 {
     /// Infinity (∞).
     #[stable(feature = "assoc_int_consts", since = "1.43.0")]
     pub const INFINITY: f32 = 1.0_f32 / 0.0_f32;
-    /// Negative infinity (-∞).
+    /// Negative infinity (−∞).
     #[stable(feature = "assoc_int_consts", since = "1.43.0")]
     pub const NEG_INFINITY: f32 = -1.0_f32 / 0.0_f32;
 

src/libcore/num/f64.rs

@@ -366,7 +366,7 @@ impl f64 {
     /// Infinity (∞).
     #[stable(feature = "assoc_int_consts", since = "1.43.0")]
     pub const INFINITY: f64 = 1.0_f64 / 0.0_f64;
-    /// Negative infinity (-∞).
+    /// Negative infinity (−∞).
     #[stable(feature = "assoc_int_consts", since = "1.43.0")]
     pub const NEG_INFINITY: f64 = -1.0_f64 / 0.0_f64;
 

src/librustc_ast_lowering/lib.rs

@@ -33,7 +33,7 @@
 #![feature(array_value_iter)]
 #![feature(crate_visibility_modifier)]
 #![feature(marker_trait_attr)]
-#![feature(specialization)]
+#![feature(specialization)] // FIXME: min_specialization does not work
 #![feature(or_patterns)]
 #![recursion_limit = "256"]
 

src/librustc_data_structures/lib.rs

@@ -12,7 +12,7 @@
 #![feature(generators)]
 #![feature(generator_trait)]
 #![feature(fn_traits)]
-#![feature(specialization)]
+#![feature(min_specialization)]
 #![feature(optin_builtin_traits)]
 #![feature(nll)]
 #![feature(allow_internal_unstable)]

src/librustc_error_codes/error_codes/E0571.md

@@ -7,7 +7,7 @@ Example of erroneous code:
 # fn satisfied(n: usize) -> bool { n % 23 == 0 }
 let result = while true {
     if satisfied(i) {
-        break 2*i; // error: `break` with value from a `while` loop
+        break 2 * i; // error: `break` with value from a `while` loop
     }
     i += 1;
 };
@@ -22,9 +22,9 @@ Make sure `break value;` statements only occur in `loop` loops:
 ```
 # let mut i = 1;
 # fn satisfied(n: usize) -> bool { n % 23 == 0 }
-let result = loop { // ok!
+let result = loop { // This is now a "loop" loop.
     if satisfied(i) {
-        break 2*i;
+        break 2 * i; // ok!
     }
     i += 1;
 };

src/librustc_hir/lib.rs

@@ -8,7 +8,7 @@
 #![feature(const_panic)]
 #![feature(in_band_lifetimes)]
 #![feature(or_patterns)]
-#![feature(specialization)]
+#![feature(min_specialization)]
 #![recursion_limit = "256"]
 
 #[macro_use]

src/librustc_lint/builtin.rs

@@ -28,8 +28,8 @@ use rustc_ast::visit::{FnCtxt, FnKind};
 use rustc_ast_pretty::pprust::{self, expr_to_string};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::{Applicability, DiagnosticBuilder};
-use rustc_feature::Stability;
 use rustc_feature::{deprecated_attributes, AttributeGate, AttributeTemplate, AttributeType};
+use rustc_feature::{GateIssue, Stability};
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::DefId;
@@ -1817,13 +1817,21 @@ impl EarlyLintPass for IncompleteFeatures {
             .map(|(name, span, _)| (name, span))
             .chain(features.declared_lib_features.iter().map(|(name, span)| (name, span)))
             .filter(|(name, _)| rustc_feature::INCOMPLETE_FEATURES.iter().any(|f| name == &f))
-            .for_each(|(name, &span)| {
+            .for_each(|(&name, &span)| {
                 cx.struct_span_lint(INCOMPLETE_FEATURES, span, |lint| {
-                    lint.build(&format!(
-                        "the feature `{}` is incomplete and may cause the compiler to crash",
+                    let mut builder = lint.build(&format!(
+                        "the feature `{}` is incomplete and may not be safe to use \
+                         and/or cause compiler crashes",
                         name,
-                    ))
-                    .emit()
+                    ));
+                    if let Some(n) = rustc_feature::find_feature_issue(name, GateIssue::Language) {
+                        builder.note(&format!(
+                            "see issue #{} <https://github.com/rust-lang/rust/issues/{}> \
+                             for more information",
+                            n, n,
+                        ));
+                    }
+                    builder.emit();
                 })
             });
     }

src/librustc_metadata/lib.rs

@@ -7,7 +7,7 @@
 #![feature(nll)]
 #![feature(or_patterns)]
 #![feature(proc_macro_internals)]
-#![feature(specialization)]
+#![feature(specialization)] // FIXME: min_specialization ICEs
 #![feature(stmt_expr_attributes)]
 #![recursion_limit = "256"]
 

src/librustc_middle/lib.rs

@@ -41,7 +41,7 @@
 #![feature(option_expect_none)]
 #![feature(or_patterns)]
 #![feature(range_is_empty)]
-#![feature(specialization)]
+#![feature(specialization)] // FIXME: min_specialization does not work
 #![feature(track_caller)]
 #![feature(trusted_len)]
 #![feature(vec_remove_item)]

src/librustc_middle/ty/print/pretty.rs

@@ -701,12 +701,14 @@ pub trait PrettyPrinter<'tcx>:
                 if self.tcx().sess.verbose() {
                     p!(write("{:?}", sz));
                 } else if let ty::ConstKind::Unevaluated(..) = sz.val {
-                    // do not try to evaluate unevaluated constants. If we are const evaluating an
+                    // Do not try to evaluate unevaluated constants. If we are const evaluating an
                     // array length anon const, rustc will (with debug assertions) print the
                     // constant's path. Which will end up here again.
                     p!(write("_"));
                 } else if let Some(n) = sz.val.try_to_bits(self.tcx().data_layout.pointer_size) {
                     p!(write("{}", n));
+                } else if let ty::ConstKind::Param(param) = sz.val {
+                    p!(write("{}", param));
                 } else {
                     p!(write("_"));
                 }

src/librustc_mir/lib.rs

@@ -19,7 +19,7 @@ Rust MIR: a lowered representation of Rust.
 #![feature(exhaustive_patterns)]
 #![feature(iter_order_by)]
 #![feature(never_type)]
-#![feature(specialization)]
+#![feature(min_specialization)]
 #![feature(trusted_len)]
 #![feature(try_blocks)]
 #![feature(associated_type_bounds)]

src/librustc_query_system/lib.rs

@@ -4,7 +4,7 @@
 #![feature(const_panic)]
 #![feature(core_intrinsics)]
 #![feature(hash_raw_entry)]
-#![feature(specialization)]
+#![feature(specialization)] // FIXME: min_specialization rejects `default const`
 #![feature(stmt_expr_attributes)]
 #![feature(vec_remove_item)]
 

src/librustc_session/session.rs

@@ -808,7 +808,7 @@ impl Session {
                 let mut fuel = self.optimization_fuel.lock();
                 ret = fuel.remaining != 0;
                 if fuel.remaining == 0 && !fuel.out_of_fuel {
-                    eprintln!("optimization-fuel-exhausted: {}", msg());
+                    self.warn(&format!("optimization-fuel-exhausted: {}", msg()));
                     fuel.out_of_fuel = true;
                 } else if fuel.remaining > 0 {
                     fuel.remaining -= 1;

src/librustc_span/lib.rs

@@ -12,7 +12,7 @@
 #![feature(negative_impls)]
 #![feature(nll)]
 #![feature(optin_builtin_traits)]
-#![feature(specialization)]
+#![feature(min_specialization)]
 
 // FIXME(#56935): Work around ICEs during cross-compilation.
 #[allow(unused)]

src/librustdoc/html/render.rs

@@ -2281,7 +2281,10 @@ fn short_stability(item: &clean::Item, cx: &Context) -> Vec<String> {
             );
             message.push_str(&format!(": {}", html.to_string()));
         }
-        stability.push(format!("<div class='stab deprecated'>{}</div>", message));
+        stability.push(format!(
+            "<div class='stab deprecated'><span class='emoji'>👎</span> {}</div>",
+            message,
+        ));
     }
 
     if let Some(stab) = item.stability.as_ref().filter(|stab| stab.level == stability::Unstable) {

src/libserialize/lib.rs

@@ -10,7 +10,7 @@ Core encoding and decoding interfaces.
     test(attr(allow(unused_variables), deny(warnings)))
 )]
 #![feature(box_syntax)]
-#![feature(specialization)]
+#![feature(specialization)] // FIXME: min_specialization does not work
 #![feature(never_type)]
 #![feature(nll)]
 #![feature(associated_type_bounds)]

src/test/incremental/const-generics/issue-62536.rs

@@ -1,6 +1,6 @@
 // revisions:cfail1
 #![feature(const_generics)]
-//[cfail1]~^ WARN the feature `const_generics` is incomplete and may cause the compiler to crash
+//[cfail1]~^ WARN the feature `const_generics` is incomplete
 
 struct S<T, const N: usize>([T; N]);
 

src/test/incremental/const-generics/issue-64087.rs

@@ -1,6 +1,6 @@
 // revisions:cfail1
 #![feature(const_generics)]
-//[cfail1]~^ WARN the feature `const_generics` is incomplete and may cause the compiler to crash
+//[cfail1]~^ WARN the feature `const_generics` is incomplete
 
 fn combinator<T, const S: usize>() -> [T; S] {}
 //[cfail1]~^ ERROR mismatched types

src/test/rustdoc/issue-32374.rs

@@ -10,7 +10,7 @@
 // @matches issue_32374/index.html '//*[@class="docblock-short"]/text()' 'Docs'
 
 // @has issue_32374/struct.T.html '//*[@class="stab deprecated"]' \
-//      'Deprecated since 1.0.0: text'
+//      '👎 Deprecated since 1.0.0: text'
 // @has - '<code>test</code>&nbsp;<a href="http://issue_url/32374">#32374</a>'
 // @matches issue_32374/struct.T.html '//*[@class="stab unstable"]' \
 //      '🔬 This is a nightly-only experimental API. \(test\s#32374\)$'
@@ -20,7 +20,7 @@
 pub struct T;
 
 // @has issue_32374/struct.U.html '//*[@class="stab deprecated"]' \
-//      'Deprecated since 1.0.0: deprecated'
+//      '👎 Deprecated since 1.0.0: deprecated'
 // @has issue_32374/struct.U.html '//*[@class="stab unstable"]' \
 //      '🔬 This is a nightly-only experimental API. (test #32374)'
 // @has issue_32374/struct.U.html '//details' \

src/test/ui/array-slice-vec/match_arr_unknown_len.rs

@@ -1,5 +1,5 @@
 #![feature(const_generics)]
-//~^ WARN the feature `const_generics` is incomplete and may cause the compiler to crash
+//~^ WARN the feature `const_generics` is incomplete
 
 fn is_123<const N: usize>(x: [u32; N]) -> bool {
     match x {

src/test/ui/array-slice-vec/match_arr_unknown_len.stderr

@@ -1,10 +1,11 @@
-warning: the feature `const_generics` is incomplete and may cause the compiler to crash
+warning: the feature `const_generics` is incomplete and may not be safe to use and/or cause compiler crashes
   --> $DIR/match_arr_unknown_len.rs:1:12
    |
 LL | #![feature(const_generics)]
    |            ^^^^^^^^^^^^^^
    |
    = note: `#[warn(incomplete_features)]` on by default
+   = note: see issue #44580 <https://github.com/rust-lang/rust/issues/44580> for more information
 
 error[E0308]: mismatched types
   --> $DIR/match_arr_unknown_len.rs:6:9
@@ -13,7 +14,7 @@ LL |         [1, 2] => true,
    |         ^^^^^^ expected `2usize`, found `N`
    |
    = note: expected array `[u32; 2]`
-              found array `[u32; _]`
+              found array `[u32; N]`
 
 error: aborting due to previous error; 1 warning emitted
 

src/test/ui/associated-type-bounds/duplicate.rs

@@ -2,7 +2,7 @@
 
 #![feature(associated_type_bounds)]
 #![feature(type_alias_impl_trait)]
-#![feature(impl_trait_in_bindings)] //~ WARN the feature `impl_trait_in_bindings` is incomplete and may cause the compiler to crash [incomplete_features]
+#![feature(impl_trait_in_bindings)] //~ WARN the feature `impl_trait_in_bindings` is incomplete
 #![feature(untagged_unions)]
 
 use std::iter;

src/test/ui/associated-type-bounds/duplicate.stderr

@@ -1,10 +1,11 @@
-warning: the feature `impl_trait_in_bindings` is incomplete and may cause the compiler to crash
+warning: the feature `impl_trait_in_bindings` is incomplete and may not be safe to use and/or cause compiler crashes
   --> $DIR/duplicate.rs:5:12
    |
 LL | #![feature(impl_trait_in_bindings)]
    |            ^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: `#[warn(incomplete_features)]` on by default
+   = note: see issue #63065 <https://github.com/rust-lang/rust/issues/63065> for more information
 
 error[E0719]: the value of the associated type `Item` (from trait `std::iter::Iterator`) is already specified
   --> $DIR/duplicate.rs:10:36

src/test/ui/associated-type-bounds/dyn-lcsit.stderr

@@ -1,10 +1,11 @@
-warning: the feature `impl_trait_in_bindings` is incomplete and may cause the compiler to crash
+warning: the feature `impl_trait_in_bindings` is incomplete and may not be safe to use and/or cause compiler crashes
   --> $DIR/dyn-lcsit.rs:4:12
    |
 LL | #![feature(impl_trait_in_bindings)]
    |            ^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: `#[warn(incomplete_features)]` on by default
+   = note: see issue #63065 <https://github.com/rust-lang/rust/issues/63065> for more information
 
 warning: 1 warning emitted
 

src/test/ui/associated-type-bounds/lcsit.stderr

@@ -1,10 +1,11 @@
-warning: the feature `impl_trait_in_bindings` is incomplete and may cause the compiler to crash
+warning: the feature `impl_trait_in_bindings` is incomplete and may not be safe to use and/or cause compiler crashes
   --> $DIR/lcsit.rs:4:12
    |
 LL | #![feature(impl_trait_in_bindings)]
    |            ^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: `#[warn(incomplete_features)]` on by default
+   = note: see issue #63065 <https://github.com/rust-lang/rust/issues/63065> for more information
 
 warning: 1 warning emitted
 

src/test/ui/binding/const-param.stderr

@@ -1,10 +1,11 @@
-warning: the feature `const_generics` is incomplete and may cause the compiler to crash
+warning: the feature `const_generics` is incomplete and may not be safe to use and/or cause compiler crashes
   --> $DIR/const-param.rs:3:12
    |
 LL | #![feature(const_generics)]
    |            ^^^^^^^^^^^^^^
    |
    = note: `#[warn(incomplete_features)]` on by default
+   = note: see issue #44580 <https://github.com/rust-lang/rust/issues/44580> for more information
 
 error[E0158]: const parameters cannot be referenced in patterns
   --> $DIR/const-param.rs:7:9

src/test/ui/const-generics/apit-with-const-param.rs

@@ -1,7 +1,7 @@
 // check-pass
 
 #![feature(const_generics)]
-//~^ WARN the feature `const_generics` is incomplete and may cause the compiler to crash
+//~^ WARN the feature `const_generics` is incomplete
 
 trait Trait {}
 

src/test/ui/const-generics/apit-with-const-param.stderr

@@ -1,10 +1,11 @@
-warning: the feature `const_generics` is incomplete and may cause the compiler to crash
+warning: the feature `const_generics` is incomplete and may not be safe to use and/or cause compiler crashes
   --> $DIR/apit-with-const-param.rs:3:12
    |
 LL | #![feature(const_generics)]
    |            ^^^^^^^^^^^^^^
    |
    = note: `#[warn(incomplete_features)]` on by default
+   = note: see issue #44580 <https://github.com/rust-lang/rust/issues/44580> for more information
 
 warning: 1 warning emitted
 

src/test/ui/const-generics/argument_order.rs

@@ -1,5 +1,5 @@
 #![feature(const_generics)]
-//~^ WARN the feature `const_generics` is incomplete and may cause the compiler to crash
+//~^ WARN the feature `const_generics` is incomplete
 
 struct Bad<const N: usize, T> { //~ ERROR type parameters must be declared prior
     arr: [u8; { N }],

src/test/ui/const-generics/argument_order.stderr

@@ -4,13 +4,14 @@ error: type parameters must be declared prior to const parameters
 LL | struct Bad<const N: usize, T> {
    |           -----------------^- help: reorder the parameters: lifetimes, then types, then consts: `<T, const N: usize>`
 
-warning: the feature `const_generics` is incomplete and may cause the compiler to crash
+warning: the feature `const_generics` is incomplete and may not be safe to use and/or cause compiler crashes
   --> $DIR/argument_order.rs:1:12
    |
 LL | #![feature(const_generics)]
    |            ^^^^^^^^^^^^^^
    |
    = note: `#[warn(incomplete_features)]` on by default
+   = note: see issue #44580 <https://github.com/rust-lang/rust/issues/44580> for more information
 
 error: aborting due to previous error; 1 warning emitted
 

src/test/ui/const-generics/array-impls/alloc-types-no-impls-length-33.stderr

@@ -29,7 +29,7 @@ LL |     let boxed_array = <Box<[i32; 33]>>::try_from(boxed_slice);
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `std::convert::TryFrom<std::boxed::Box<[i32]>>` is not implemented for `std::boxed::Box<[i32; 33]>`
    |
    = help: the following implementations were found:
-             <std::boxed::Box<[T; _]> as std::convert::TryFrom<std::boxed::Box<[T]>>>
+             <std::boxed::Box<[T; N]> as std::convert::TryFrom<std::boxed::Box<[T]>>>
 
 error[E0277]: the trait bound `std::rc::Rc<[i32; 33]>: std::convert::From<std::rc::Rc<[i32]>>` is not satisfied
   --> $DIR/alloc-types-no-impls-length-33.rs:19:23
@@ -53,7 +53,7 @@ LL |     let boxed_array = <Rc<[i32; 33]>>::try_from(boxed_slice);
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `std::convert::TryFrom<std::rc::Rc<[i32]>>` is not implemented for `std::rc::Rc<[i32; 33]>`
    |
    = help: the following implementations were found:
-             <std::rc::Rc<[T; _]> as std::convert::TryFrom<std::rc::Rc<[T]>>>
+             <std::rc::Rc<[T; N]> as std::convert::TryFrom<std::rc::Rc<[T]>>>
 
 error[E0277]: the trait bound `std::sync::Arc<[i32; 33]>: std::convert::From<std::sync::Arc<[i32]>>` is not satisfied
   --> $DIR/alloc-types-no-impls-length-33.rs:26:23
@@ -77,7 +77,7 @@ LL |     let boxed_array = <Arc<[i32; 33]>>::try_from(boxed_slice);
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `std::convert::TryFrom<std::sync::Arc<[i32]>>` is not implemented for `std::sync::Arc<[i32; 33]>`
    |
    = help: the following implementations were found:
-             <std::sync::Arc<[T; _]> as std::convert::TryFrom<std::sync::Arc<[T]>>>
+             <std::sync::Arc<[T; N]> as std::convert::TryFrom<std::sync::Arc<[T]>>>
 
 error: aborting due to 7 previous errors