Auto merge of #58415 - Centril:rollup, r=Centril

Rollup of 12 pull requests

Successful merges:

 - #57693 (Doc rewording)
 - #57815 (Speed up the fast path for assert_eq! and assert_ne!)
 - #58034 (Stabilize the time_checked_add feature)
 - #58057 (Stabilize linker-plugin based LTO (aka cross-language LTO))
 - #58137 (Cleanup: rename node_id_to_type(_opt))
 - #58166 (allow shorthand syntax for deprecation reason)
 - #58200 (fix str mutating through a ptr derived from &self)
 - #58273 (Rename rustc_errors dependency in rust 2018 crates)
 - #58289 (impl iter() for dyn Error)
 - #58387 (Disallow `auto` trait alias syntax)
 - #58404 (use Ubuntu keyserver for CloudABI ports)
 - #58405 (Remove some dead code from libcore)

Failed merges:

r? @ghost

4 files changed, 13 insertions, 8 deletions

diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index 9168d4b61c1..babe0eef20f 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -1,10 +1,10 @@
 use crate::ast::{self, Ident};
 use crate::source_map::{SourceMap, FilePathMapping};
-use crate::errors::{Applicability, FatalError, Diagnostic, DiagnosticBuilder};
 use crate::parse::{token, ParseSess};
 use crate::symbol::{Symbol, keywords};
 
-use syntax_pos::{self, BytePos, CharPos, Pos, Span, NO_EXPANSION};
+use errors::{Applicability, FatalError, Diagnostic, DiagnosticBuilder};
+use syntax_pos::{BytePos, CharPos, Pos, Span, NO_EXPANSION};
 use core::unicode::property::Pattern_White_Space;
 
 use std::borrow::Cow;
@@ -1882,7 +1882,6 @@ mod tests {
     use crate::ast::{Ident, CrateConfig};
     use crate::symbol::Symbol;
     use crate::source_map::SourceMap;
-    use crate::errors;
     use crate::feature_gate::UnstableFeatures;
     use crate::parse::token;
     use crate::diagnostics::plugin::ErrorMap;
diff --git a/src/libsyntax/parse/lexer/unicode_chars.rs b/src/libsyntax/parse/lexer/unicode_chars.rs
index 75862178169..7da4284c0e4 100644
--- a/src/libsyntax/parse/lexer/unicode_chars.rs
+++ b/src/libsyntax/parse/lexer/unicode_chars.rs
@@ -2,7 +2,7 @@
 // http://www.unicode.org/Public/security/10.0.0/confusables.txt
 
 use syntax_pos::{Span, NO_EXPANSION};
-use crate::errors::{Applicability, DiagnosticBuilder};
+use errors::{Applicability, DiagnosticBuilder};
 use super::StringReader;
 
 const UNICODE_ARRAY: &[(char, &str, char)] = &[
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index 69940ae621c..b2d4d97d57d 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -3,7 +3,6 @@
 use crate::ast::{self, CrateConfig, NodeId};
 use crate::early_buffered_lints::{BufferedEarlyLint, BufferedEarlyLintId};
 use crate::source_map::{SourceMap, FilePathMapping};
-use crate::errors::{FatalError, Level, Handler, ColorConfig, Diagnostic, DiagnosticBuilder};
 use crate::feature_gate::UnstableFeatures;
 use crate::parse::parser::Parser;
 use crate::symbol::Symbol;
@@ -11,6 +10,7 @@ use crate::tokenstream::{TokenStream, TokenTree};
 use crate::diagnostics::plugin::ErrorMap;
 use crate::print::pprust::token_to_string;
 
+use errors::{FatalError, Level, Handler, ColorConfig, Diagnostic, DiagnosticBuilder};
 use rustc_data_structures::sync::{Lrc, Lock};
 use syntax_pos::{Span, SourceFile, FileName, MultiSpan};
 use log::debug;
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 67154305735..e22047938e5 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -33,7 +33,6 @@ use crate::ast::{RangeEnd, RangeSyntax};
 use crate::{ast, attr};
 use crate::ext::base::DummyResult;
 use crate::source_map::{self, SourceMap, Spanned, respan};
-use crate::errors::{self, Applicability, DiagnosticBuilder, DiagnosticId};
 use crate::parse::{self, SeqSep, classify, token};
 use crate::parse::lexer::{TokenAndSpan, UnmatchedBrace};
 use crate::parse::lexer::comments::{doc_comment_style, strip_doc_comment_decoration};
@@ -47,8 +46,9 @@ use crate::ThinVec;
 use crate::tokenstream::{self, DelimSpan, TokenTree, TokenStream, TreeAndJoint};
 use crate::symbol::{Symbol, keywords};
 
+use errors::{Applicability, DiagnosticBuilder, DiagnosticId};
 use rustc_target::spec::abi::{self, Abi};
-use syntax_pos::{self, Span, MultiSpan, BytePos, FileName};
+use syntax_pos::{Span, MultiSpan, BytePos, FileName};
 use log::{debug, trace};
 
 use std::borrow::Cow;
@@ -6538,8 +6538,14 @@ impl<'a> Parser<'a> {
             let bounds = self.parse_generic_bounds()?;
             tps.where_clause = self.parse_where_clause()?;
             self.expect(&token::Semi)?;
+            if is_auto == IsAuto::Yes {
+                let msg = "trait aliases cannot be `auto`";
+                self.struct_span_err(self.prev_span, msg)
+                    .span_label(self.prev_span, msg)
+                    .emit();
+            }
             if unsafety != Unsafety::Normal {
-                let msg = "trait aliases cannot be unsafe";
+                let msg = "trait aliases cannot be `unsafe`";
                 self.struct_span_err(self.prev_span, msg)
                     .span_label(self.prev_span, msg)
                     .emit();