Merge pull request #2388 from rust-lang/rustc-pull

Rustc pull update

2 files changed, 17 insertions, 15 deletions

diff --git a/compiler/rustc_span/src/lib.rs b/compiler/rustc_span/src/lib.rs
index 61c96e67c17..22ca8accf9f 100644
--- a/compiler/rustc_span/src/lib.rs
+++ b/compiler/rustc_span/src/lib.rs
@@ -17,7 +17,6 @@
 
 // tidy-alphabetical-start
 #![allow(internal_features)]
-#![cfg_attr(bootstrap, feature(let_chains))]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![doc(rust_logo)]
 #![feature(array_windows)]
diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index 40cec408308..3a95447308a 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -1301,6 +1301,10 @@ symbols! {
         match_beginning_vert,
         match_default_bindings,
         matches_macro,
+        maximumf128,
+        maximumf16,
+        maximumf32,
+        maximumf64,
         maxnumf128,
         maxnumf16,
         maxnumf32,
@@ -1335,6 +1339,10 @@ symbols! {
         min_generic_const_args,
         min_specialization,
         min_type_alias_impl_trait,
+        minimumf128,
+        minimumf16,
+        minimumf32,
+        minimumf64,
         minnumf128,
         minnumf16,
         minnumf32,
@@ -2099,7 +2107,6 @@ symbols! {
         three_way_compare,
         thumb2,
         thumb_mode: "thumb-mode",
-        time,
         tmm_reg,
         to_owned_method,
         to_string,
@@ -2342,6 +2349,9 @@ pub const STDLIB_STABLE_CRATES: &[Symbol] = &[sym::std, sym::core, sym::alloc, s
 
 #[derive(Copy, Clone, Eq, HashStable_Generic, Encodable, Decodable)]
 pub struct Ident {
+    // `name` should never be the empty symbol. If you are considering that,
+    // you are probably conflating "empty identifer with "no identifier" and
+    // you should use `Option<Ident>` instead.
     pub name: Symbol,
     pub span: Span,
 }
@@ -2349,28 +2359,21 @@ pub struct Ident {
 impl Ident {
     #[inline]
     /// Constructs a new identifier from a symbol and a span.
-    pub const fn new(name: Symbol, span: Span) -> Ident {
+    pub fn new(name: Symbol, span: Span) -> Ident {
+        debug_assert_ne!(name, kw::Empty);
         Ident { name, span }
     }
 
     /// Constructs a new identifier with a dummy span.
     #[inline]
-    pub const fn with_dummy_span(name: Symbol) -> Ident {
+    pub fn with_dummy_span(name: Symbol) -> Ident {
         Ident::new(name, DUMMY_SP)
     }
 
-    /// This is best avoided, because it blurs the lines between "empty
-    /// identifier" and "no identifier". Using `Option<Ident>` is preferable,
-    /// where possible, because that is unambiguous.
-    #[inline]
-    pub fn empty() -> Ident {
-        Ident::with_dummy_span(kw::Empty)
-    }
-
     // For dummy identifiers that are never used and absolutely must be
-    // present, it's better to use `Ident::dummy` than `Ident::Empty`, because
-    // it's clearer that it's intended as a dummy value, and more likely to be
-    // detected if it accidentally does get used.
+    // present. Note that this does *not* use the empty symbol; `sym::dummy`
+    // makes it clear that it's intended as a dummy value, and is more likely
+    // to be detected if it accidentally does get used.
     #[inline]
     pub fn dummy() -> Ident {
         Ident::with_dummy_span(sym::dummy)