Rollup of 5 pull requests

src/bootstrap/doc.rs

@@ -49,7 +49,7 @@ macro_rules! book {
                 builder.ensure(RustbookSrc {
                     target: self.target,
                     name: INTERNER.intern_str($book_name),
-                    src: doc_src(builder),
+                    src: INTERNER.intern_path(builder.src.join($path)),
                 })
             }
         }
@@ -60,6 +60,7 @@ macro_rules! book {
 // NOTE: When adding a book here, make sure to ALSO build the book by
 // adding a build step in `src/bootstrap/builder.rs`!
 book!(
+    CargoBook, "src/tools/cargo/src/doc", "cargo";
     EditionGuide, "src/doc/edition-guide", "edition-guide";
     EmbeddedBook, "src/doc/embedded-book", "embedded-book";
     Nomicon, "src/doc/nomicon", "nomicon";
@@ -69,10 +70,6 @@ book!(
     RustdocBook, "src/doc/rustdoc", "rustdoc";
 );
 
-fn doc_src(builder: &Builder<'_>) -> Interned<PathBuf> {
-    INTERNER.intern_path(builder.src.join("src/doc"))
-}
-
 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
 pub struct UnstableBook {
     target: Interned<String>,
@@ -96,48 +93,11 @@ impl Step for UnstableBook {
         builder.ensure(RustbookSrc {
             target: self.target,
             name: INTERNER.intern_str("unstable-book"),
-            src: builder.md_doc_out(self.target),
+            src: INTERNER.intern_path(builder.md_doc_out(self.target).join("unstable-book")),
         })
     }
 }
 
-#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
-pub struct CargoBook {
-    target: Interned<String>,
-    name: Interned<String>,
-}
-
-impl Step for CargoBook {
-    type Output = ();
-    const DEFAULT: bool = true;
-
-    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
-        let builder = run.builder;
-        run.path("src/tools/cargo/src/doc/book").default_condition(builder.config.docs)
-    }
-
-    fn make_run(run: RunConfig<'_>) {
-        run.builder.ensure(CargoBook { target: run.target, name: INTERNER.intern_str("cargo") });
-    }
-
-    fn run(self, builder: &Builder<'_>) {
-        let target = self.target;
-        let name = self.name;
-        let src = builder.src.join("src/tools/cargo/src/doc");
-
-        let out = builder.doc_out(target);
-        t!(fs::create_dir_all(&out));
-
-        let out = out.join(name);
-
-        builder.info(&format!("Cargo Book ({}) - {}", target, name));
-
-        let _ = fs::remove_dir_all(&out);
-
-        builder.run(builder.tool_cmd(Tool::Rustbook).arg("build").arg(&src).arg("-d").arg(out));
-    }
-}
-
 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
 struct RustbookSrc {
     target: Interned<String>,
@@ -164,7 +124,6 @@ impl Step for RustbookSrc {
         t!(fs::create_dir_all(&out));
 
         let out = out.join(name);
-        let src = src.join(name);
         let index = out.join("index.html");
         let rustbook = builder.tool_exe(Tool::Rustbook);
         let mut rustbook_cmd = builder.tool_cmd(Tool::Rustbook);
@@ -182,7 +141,6 @@ impl Step for RustbookSrc {
 pub struct TheBook {
     compiler: Compiler,
     target: Interned<String>,
-    name: &'static str,
 }
 
 impl Step for TheBook {
@@ -198,53 +156,37 @@ impl Step for TheBook {
         run.builder.ensure(TheBook {
             compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
             target: run.target,
-            name: "book",
         });
     }
 
     /// Builds the book and associated stuff.
     ///
     /// We need to build:
     ///
-    /// * Book (first edition)
-    /// * Book (second edition)
+    /// * Book
+    /// * Older edition redirects
     /// * Version info and CSS
     /// * Index page
     /// * Redirect pages
     fn run(self, builder: &Builder<'_>) {
         let compiler = self.compiler;
         let target = self.target;
-        let name = self.name;
 
         // build book
         builder.ensure(RustbookSrc {
             target,
-            name: INTERNER.intern_string(name.to_string()),
-            src: doc_src(builder),
+            name: INTERNER.intern_str("book"),
+            src: INTERNER.intern_path(builder.src.join("src/doc/book")),
         });
 
         // building older edition redirects
-
-        let source_name = format!("{}/first-edition", name);
-        builder.ensure(RustbookSrc {
-            target,
-            name: INTERNER.intern_string(source_name),
-            src: doc_src(builder),
-        });
-
-        let source_name = format!("{}/second-edition", name);
-        builder.ensure(RustbookSrc {
-            target,
-            name: INTERNER.intern_string(source_name),
-            src: doc_src(builder),
-        });
-
-        let source_name = format!("{}/2018-edition", name);
-        builder.ensure(RustbookSrc {
-            target,
-            name: INTERNER.intern_string(source_name),
-            src: doc_src(builder),
-        });
+        for edition in &["first-edition", "second-edition", "2018-edition"] {
+            builder.ensure(RustbookSrc {
+                target,
+                name: INTERNER.intern_string(format!("book/{}", edition)),
+                src: INTERNER.intern_path(builder.src.join("src/doc/book").join(edition)),
+            });
+        }
 
         // build the version info page and CSS
         builder.ensure(Standalone { compiler, target });
@@ -531,7 +473,7 @@ impl Step for Rustc {
 
         // Build cargo command.
         let mut cargo = builder.cargo(compiler, Mode::Rustc, target, "doc");
-        cargo.env("RUSTDOCFLAGS", "--document-private-items --passes strip-hidden");
+        cargo.env("RUSTDOCFLAGS", "--document-private-items");
         compile::rustc_cargo(builder, &mut cargo, target);
 
         // Only include compiler crates, no dependencies of those, such as `libc`.

src/libpanic_unwind/emcc.rs

@@ -63,7 +63,7 @@ pub unsafe fn cleanup(ptr: *mut u8) -> Box<dyn Any + Send> {
 pub unsafe fn panic(data: Box<dyn Any + Send>) -> u32 {
     let sz = mem::size_of_val(&data);
     let exception = __cxa_allocate_exception(sz);
-    if exception == ptr::null_mut() {
+    if exception.is_null() {
         return uw::_URC_FATAL_PHASE1_ERROR as u32;
     }
     ptr::write(exception as *mut _, data);

src/librustc/ty/util.rs

@@ -3,18 +3,18 @@
 use crate::hir::map::DefPathData;
 use crate::ich::NodeIdHashingMode;
 use crate::mir::interpret::{sign_extend, truncate};
-use crate::ty::layout::{Integer, IntegerExt};
+use crate::ty::layout::{Integer, IntegerExt, Size};
 use crate::ty::query::TyCtxtAt;
 use crate::ty::subst::{GenericArgKind, InternalSubsts, Subst, SubstsRef};
 use crate::ty::TyKind::*;
 use crate::ty::{self, DefIdTree, GenericParamDefKind, Ty, TyCtxt, TypeFoldable};
 use crate::util::common::ErrorReported;
+use rustc_apfloat::Float as _;
+use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::DefId;
-
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_macros::HashStable;
 use rustc_span::Span;
 use std::{cmp, fmt};
@@ -43,41 +43,54 @@ impl<'tcx> fmt::Display for Discr<'tcx> {
     }
 }
 
+fn signed_min(size: Size) -> i128 {
+    sign_extend(1_u128 << (size.bits() - 1), size) as i128
+}
+
+fn signed_max(size: Size) -> i128 {
+    i128::max_value() >> (128 - size.bits())
+}
+
+fn unsigned_max(size: Size) -> u128 {
+    u128::max_value() >> (128 - size.bits())
+}
+
+fn int_size_and_signed<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> (Size, bool) {
+    let (int, signed) = match ty.kind {
+        Int(ity) => (Integer::from_attr(&tcx, SignedInt(ity)), true),
+        Uint(uty) => (Integer::from_attr(&tcx, UnsignedInt(uty)), false),
+        _ => bug!("non integer discriminant"),
+    };
+    (int.size(), signed)
+}
+
 impl<'tcx> Discr<'tcx> {
     /// Adds `1` to the value and wraps around if the maximum for the type is reached.
     pub fn wrap_incr(self, tcx: TyCtxt<'tcx>) -> Self {
         self.checked_add(tcx, 1).0
     }
     pub fn checked_add(self, tcx: TyCtxt<'tcx>, n: u128) -> (Self, bool) {
-        let (int, signed) = match self.ty.kind {
-            Int(ity) => (Integer::from_attr(&tcx, SignedInt(ity)), true),
-            Uint(uty) => (Integer::from_attr(&tcx, UnsignedInt(uty)), false),
-            _ => bug!("non integer discriminant"),
-        };
-
-        let size = int.size();
-        let bit_size = int.size().bits();
-        let shift = 128 - bit_size;
-        if signed {
-            let sext = |u| sign_extend(u, size) as i128;
-            let min = sext(1_u128 << (bit_size - 1));
-            let max = i128::max_value() >> shift;
-            let val = sext(self.val);
+        let (size, signed) = int_size_and_signed(tcx, self.ty);
+        let (val, oflo) = if signed {
+            let min = signed_min(size);
+            let max = signed_max(size);
+            let val = sign_extend(self.val, size) as i128;
             assert!(n < (i128::max_value() as u128));
             let n = n as i128;
             let oflo = val > max - n;
             let val = if oflo { min + (n - (max - val) - 1) } else { val + n };
             // zero the upper bits
             let val = val as u128;
             let val = truncate(val, size);
-            (Self { val: val as u128, ty: self.ty }, oflo)
+            (val, oflo)
         } else {
-            let max = u128::max_value() >> shift;
+            let max = unsigned_max(size);
             let val = self.val;
             let oflo = val > max - n;
             let val = if oflo { n - (max - val) - 1 } else { val + n };
-            (Self { val: val, ty: self.ty }, oflo)
-        }
+            (val, oflo)
+        };
+        (Self { val, ty: self.ty }, oflo)
     }
 }
 
@@ -621,6 +634,44 @@ impl<'tcx> TyCtxt<'tcx> {
 }
 
 impl<'tcx> ty::TyS<'tcx> {
+    /// Returns the maximum value for the given numeric type (including `char`s)
+    /// or returns `None` if the type is not numeric.
+    pub fn numeric_max_val(&'tcx self, tcx: TyCtxt<'tcx>) -> Option<&'tcx ty::Const<'tcx>> {
+        let val = match self.kind {
+            ty::Int(_) | ty::Uint(_) => {
+                let (size, signed) = int_size_and_signed(tcx, self);
+                let val = if signed { signed_max(size) as u128 } else { unsigned_max(size) };
+                Some(val)
+            }
+            ty::Char => Some(std::char::MAX as u128),
+            ty::Float(fty) => Some(match fty {
+                ast::FloatTy::F32 => ::rustc_apfloat::ieee::Single::INFINITY.to_bits(),
+                ast::FloatTy::F64 => ::rustc_apfloat::ieee::Double::INFINITY.to_bits(),
+            }),
+            _ => None,
+        };
+        val.map(|v| ty::Const::from_bits(tcx, v, ty::ParamEnv::empty().and(self)))
+    }
+
+    /// Returns the minimum value for the given numeric type (including `char`s)
+    /// or returns `None` if the type is not numeric.
+    pub fn numeric_min_val(&'tcx self, tcx: TyCtxt<'tcx>) -> Option<&'tcx ty::Const<'tcx>> {
+        let val = match self.kind {
+            ty::Int(_) | ty::Uint(_) => {
+                let (size, signed) = int_size_and_signed(tcx, self);
+                let val = if signed { truncate(signed_min(size) as u128, size) } else { 0 };
+                Some(val)
+            }
+            ty::Char => Some(0),
+            ty::Float(fty) => Some(match fty {
+                ast::FloatTy::F32 => (-::rustc_apfloat::ieee::Single::INFINITY).to_bits(),
+                ast::FloatTy::F64 => (-::rustc_apfloat::ieee::Double::INFINITY).to_bits(),
+            }),
+            _ => None,
+        };
+        val.map(|v| ty::Const::from_bits(tcx, v, ty::ParamEnv::empty().and(self)))
+    }
+
     /// Checks whether values of this type `T` are *moved* or *copied*
     /// when referenced -- this amounts to a check for whether `T:
     /// Copy`, but note that we **don't** consider lifetimes when

src/librustc_ast_lowering/expr.rs

@@ -202,7 +202,12 @@ impl<'hir> LoweringContext<'_, 'hir> {
             ExprKind::Mac(_) => panic!("Shouldn't exist here"),
         };
 
-        hir::Expr { hir_id: self.lower_node_id(e.id), kind, span: e.span, attrs: e.attrs.clone() }
+        hir::Expr {
+            hir_id: self.lower_node_id(e.id),
+            kind,
+            span: e.span,
+            attrs: e.attrs.iter().map(|a| self.lower_attr(a)).collect::<Vec<_>>().into(),
+        }
     }
 
     fn lower_unop(&mut self, u: UnOp) -> hir::UnOp {

src/librustc_ast_lowering/pat.rs

@@ -65,9 +65,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             PatKind::Box(ref inner) => hir::PatKind::Box(self.lower_pat(inner)),
             PatKind::Ref(ref inner, mutbl) => hir::PatKind::Ref(self.lower_pat(inner), mutbl),
             PatKind::Range(ref e1, ref e2, Spanned { node: ref end, .. }) => hir::PatKind::Range(
-                self.lower_expr(e1),
-                self.lower_expr(e2),
-                self.lower_range_end(end),
+                e1.as_deref().map(|e| self.lower_expr(e)),
+                e2.as_deref().map(|e| self.lower_expr(e)),
+                self.lower_range_end(end, e2.is_some()),
             ),
             PatKind::Slice(ref pats) => self.lower_pat_slice(pats),
             PatKind::Rest => {
@@ -253,10 +253,11 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         hir::PatKind::Wild
     }
 
-    fn lower_range_end(&mut self, e: &RangeEnd) -> hir::RangeEnd {
+    fn lower_range_end(&mut self, e: &RangeEnd, has_end: bool) -> hir::RangeEnd {
         match *e {
-            RangeEnd::Included(_) => hir::RangeEnd::Included,
-            RangeEnd::Excluded => hir::RangeEnd::Excluded,
+            RangeEnd::Excluded if has_end => hir::RangeEnd::Excluded,
+            // No end; so `X..` behaves like `RangeFrom`.
+            RangeEnd::Excluded | RangeEnd::Included(_) => hir::RangeEnd::Included,
         }
     }
 }

src/librustc_feature/active.rs

@@ -534,6 +534,9 @@ declare_features! (
     /// Allows the use of `#[cfg(sanitize = "option")]`; set when -Zsanitizer is used.
     (active, cfg_sanitize, "1.41.0", Some(39699), None),
 
+    /// Allows using `..X`, `..=X`, `...X`, and `X..` as a pattern.
+    (active, half_open_range_patterns, "1.41.0", Some(67264), None),
+
     /// Allows using `&mut` in constant functions.
     (active, const_mut_refs, "1.41.0", Some(57349), None),
 

src/librustc_hir/hir.rs

@@ -905,7 +905,7 @@ pub enum PatKind<'hir> {
     Lit(&'hir Expr<'hir>),
 
     /// A range pattern (e.g., `1..=2` or `1..2`).
-    Range(&'hir Expr<'hir>, &'hir Expr<'hir>, RangeEnd),
+    Range(Option<&'hir Expr<'hir>>, Option<&'hir Expr<'hir>>, RangeEnd),
 
     /// A slice pattern, `[before_0, ..., before_n, (slice, after_0, ..., after_n)?]`.
     ///

src/librustc_hir/intravisit.rs

@@ -766,8 +766,8 @@ pub fn walk_pat<'v, V: Visitor<'v>>(visitor: &mut V, pattern: &'v Pat<'v>) {
         }
         PatKind::Lit(ref expression) => visitor.visit_expr(expression),
         PatKind::Range(ref lower_bound, ref upper_bound, _) => {
-            visitor.visit_expr(lower_bound);
-            visitor.visit_expr(upper_bound)
+            walk_list!(visitor, visit_expr, lower_bound);
+            walk_list!(visitor, visit_expr, upper_bound);
         }
         PatKind::Wild => (),
         PatKind::Slice(prepatterns, ref slice_pattern, postpatterns) => {