Auto merge of #62902 - Mark-Simulacrum:rollup-mxfk0mm, r=Mark-Simulacrum

Rollup of 14 pull requests

Successful merges:

 - #60951 (more specific errors in src/librustc/mir/interpret/error.rs)
 - #62523 (Delay bug to resolve HRTB ICE)
 - #62656 (explain how to search in slice without owned data)
 - #62791 (Handle more cases of typos misinterpreted as type ascription)
 - #62804 (rustc_typeck: improve diagnostics for _ const/static declarations)
 - #62808 (Revert "Disable stack probing for gnux32.")
 - #62817 (Tweak span for variant not found error)
 - #62842 (Add tests for issue-58887)
 - #62851 (move unescape module to rustc_lexer)
 - #62859 (Place::as_place_ref is now Place::as_ref)
 - #62869 (add rustc_private as a proper language feature gate)
 - #62880 (normalize use of backticks in compiler messages for librustc_allocator)
 - #62885 (Change "OSX" to "macOS")
 - #62889 (Update stage0.txt)

Failed merges:

r? @ghost

README.md

@@ -200,11 +200,11 @@ fetch snapshots, and an OS that can execute the available snapshot binaries.
 
 Snapshot binaries are currently built and tested on several platforms:
 
-| Platform / Architecture  | x86 | x86_64 |
-|--------------------------|-----|--------|
-| Windows (7, 8, 10, ...)  | ✓   | ✓      |
-| Linux (2.6.18 or later)  | ✓   | ✓      |
-| OSX (10.7 Lion or later) | ✓   | ✓      |
+| Platform / Architecture    | x86 | x86_64 |
+|----------------------------|-----|--------|
+| Windows (7, 8, 10, ...)    | ✓   | ✓      |
+| Linux (2.6.18 or later)    | ✓   | ✓      |
+| macOS (10.7 Lion or later) | ✓   | ✓      |
 
 You may find that other platforms work, but these are our officially
 supported build environments that are most likely to work.

src/libcore/char/methods.rs

@@ -553,10 +553,12 @@ impl char {
     /// 'XID_Start' is a Unicode Derived Property specified in
     /// [UAX #31](http://unicode.org/reports/tr31/#NFKC_Modifications),
     /// mostly similar to `ID_Start` but modified for closure under `NFKx`.
-    #[unstable(feature = "rustc_private",
-               reason = "mainly needed for compiler internals",
-               issue = "27812")]
-    #[inline]
+    #[cfg_attr(bootstrap,
+               unstable(feature = "rustc_private",
+                        reason = "mainly needed for compiler internals",
+                        issue = "27812"))]
+    #[cfg_attr(not(bootstrap),
+               unstable(feature = "unicode_internals", issue = "0"))]
     pub fn is_xid_start(self) -> bool {
         derived_property::XID_Start(self)
     }
@@ -567,9 +569,12 @@ impl char {
     /// 'XID_Continue' is a Unicode Derived Property specified in
     /// [UAX #31](http://unicode.org/reports/tr31/#NFKC_Modifications),
     /// mostly similar to 'ID_Continue' but modified for closure under NFKx.
-    #[unstable(feature = "rustc_private",
-               reason = "mainly needed for compiler internals",
-               issue = "27812")]
+    #[cfg_attr(bootstrap,
+               unstable(feature = "rustc_private",
+                        reason = "mainly needed for compiler internals",
+                        issue = "27812"))]
+    #[cfg_attr(not(bootstrap),
+               unstable(feature = "unicode_internals", issue = "0"))]
     #[inline]
     pub fn is_xid_continue(self) -> bool {
         derived_property::XID_Continue(self)

src/libcore/slice/mod.rs

@@ -1263,6 +1263,15 @@ impl<T> [T] {
     /// assert!(v.contains(&30));
     /// assert!(!v.contains(&50));
     /// ```
+    ///
+    /// If you do not have an `&T`, but just an `&U` such that `T: Borrow<U>`
+    /// (e.g. `String: Borrow<str>`), you can use `iter().any`:
+    ///
+    /// ```
+    /// let v = [String::from("hello"), String::from("world")]; // slice of `String`
+    /// assert!(v.iter().any(|e| e == "hello")); // search with `&str`
+    /// assert!(!v.iter().any(|e| e == "hi"));
+    /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn contains(&self, x: &T) -> bool
         where T: PartialEq

src/libfmt_macros/lib.rs

@@ -13,6 +13,7 @@
 
 #![feature(nll)]
 #![feature(rustc_private)]
+#![feature(unicode_internals)]
 
 pub use Piece::*;
 pub use Position::*;

src/librustc/infer/lexical_region_resolve/mod.rs

@@ -764,16 +764,17 @@ impl<'cx, 'tcx> LexicalResolver<'cx, 'tcx> {
             }
         }
 
-        span_bug!(
+        // Errors in earlier passes can yield error variables without
+        // resolution errors here; delay ICE in favor of those errors.
+        self.tcx().sess.delay_span_bug(
             self.var_infos[node_idx].origin.span(),
-            "collect_error_for_expanding_node() could not find \
-             error for var {:?} in universe {:?}, lower_bounds={:#?}, \
-             upper_bounds={:#?}",
-            node_idx,
-            node_universe,
-            lower_bounds,
-            upper_bounds
-        );
+            &format!("collect_error_for_expanding_node() could not find \
+                      error for var {:?} in universe {:?}, lower_bounds={:#?}, \
+                      upper_bounds={:#?}",
+                     node_idx,
+                     node_universe,
+                     lower_bounds,
+                     upper_bounds));
     }
 
     fn collect_concrete_regions(

src/librustc/mir/interpret/error.rs

@@ -228,6 +228,24 @@ impl<'tcx> From<InterpError<'tcx, u64>> for InterpErrorInfo<'tcx> {
 
 pub type AssertMessage<'tcx> = InterpError<'tcx, mir::Operand<'tcx>>;
 
+#[derive(Clone, RustcEncodable, RustcDecodable, HashStable)]
+pub enum PanicMessage<O> {
+    Panic {
+        msg: Symbol,
+        line: u32,
+        col: u32,
+        file: Symbol,
+    },
+    BoundsCheck {
+        len: O,
+        index: O,
+    },
+    Overflow(mir::BinOp),
+    OverflowNeg,
+    DivisionByZero,
+    RemainderByZero,
+}
+
 #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)]
 pub enum InterpError<'tcx, O> {
     /// This variant is used by machines to signal their own errors that do not
@@ -266,11 +284,6 @@ pub enum InterpError<'tcx, O> {
     Unimplemented(String),
     DerefFunctionPointer,
     ExecuteMemory,
-    BoundsCheck { len: O, index: O },
-    Overflow(mir::BinOp),
-    OverflowNeg,
-    DivisionByZero,
-    RemainderByZero,
     Intrinsic(String),
     InvalidChar(u128),
     StackFrameLimitReached,
@@ -298,12 +311,7 @@ pub enum InterpError<'tcx, O> {
     HeapAllocZeroBytes,
     HeapAllocNonPowerOfTwoAlignment(u64),
     Unreachable,
-    Panic {
-        msg: Symbol,
-        line: u32,
-        col: u32,
-        file: Symbol,
-    },
+    Panic(PanicMessage<O>),
     ReadFromReturnPointer,
     PathNotFound(Vec<String>),
     UnimplementedTraitSelection,
@@ -369,8 +377,6 @@ impl<'tcx, O> InterpError<'tcx, O> {
                 "tried to dereference a function pointer",
             ExecuteMemory =>
                 "tried to treat a memory pointer as a function pointer",
-            BoundsCheck{..} =>
-                "array index out of bounds",
             Intrinsic(..) =>
                 "intrinsic failed",
             NoMirFor(..) =>
@@ -422,8 +428,32 @@ impl<'tcx, O> InterpError<'tcx, O> {
                 two",
             Unreachable =>
                 "entered unreachable code",
-            Panic { .. } =>
+            Panic(PanicMessage::Panic{..}) =>
                 "the evaluated program panicked",
+            Panic(PanicMessage::BoundsCheck{..}) =>
+                "array index out of bounds",
+            Panic(PanicMessage::Overflow(mir::BinOp::Add)) =>
+                "attempt to add with overflow",
+            Panic(PanicMessage::Overflow(mir::BinOp::Sub)) =>
+                "attempt to subtract with overflow",
+            Panic(PanicMessage::Overflow(mir::BinOp::Mul)) =>
+                "attempt to multiply with overflow",
+            Panic(PanicMessage::Overflow(mir::BinOp::Div)) =>
+                "attempt to divide with overflow",
+            Panic(PanicMessage::Overflow(mir::BinOp::Rem)) =>
+                "attempt to calculate the remainder with overflow",
+            Panic(PanicMessage::OverflowNeg) =>
+                "attempt to negate with overflow",
+            Panic(PanicMessage::Overflow(mir::BinOp::Shr)) =>
+                "attempt to shift right with overflow",
+            Panic(PanicMessage::Overflow(mir::BinOp::Shl)) =>
+                "attempt to shift left with overflow",
+            Panic(PanicMessage::Overflow(op)) =>
+                bug!("{:?} cannot overflow", op),
+            Panic(PanicMessage::DivisionByZero) =>
+                "attempt to divide by zero",
+            Panic(PanicMessage::RemainderByZero) =>
+                "attempt to calculate the remainder with a divisor of zero",
             ReadFromReturnPointer =>
                 "tried to read from the return pointer",
             PathNotFound(_) =>
@@ -436,17 +466,6 @@ impl<'tcx, O> InterpError<'tcx, O> {
                 "encountered overly generic constant",
             ReferencedConstant =>
                 "referenced constant has errors",
-            Overflow(mir::BinOp::Add) => "attempt to add with overflow",
-            Overflow(mir::BinOp::Sub) => "attempt to subtract with overflow",
-            Overflow(mir::BinOp::Mul) => "attempt to multiply with overflow",
-            Overflow(mir::BinOp::Div) => "attempt to divide with overflow",
-            Overflow(mir::BinOp::Rem) => "attempt to calculate the remainder with overflow",
-            OverflowNeg => "attempt to negate with overflow",
-            Overflow(mir::BinOp::Shr) => "attempt to shift right with overflow",
-            Overflow(mir::BinOp::Shl) => "attempt to shift left with overflow",
-            Overflow(op) => bug!("{:?} cannot overflow", op),
-            DivisionByZero => "attempt to divide by zero",
-            RemainderByZero => "attempt to calculate the remainder with a divisor of zero",
             GeneratorResumedAfterReturn => "generator resumed after completion",
             GeneratorResumedAfterPanic => "generator resumed after panicking",
             InfiniteLoop =>
@@ -493,8 +512,6 @@ impl<'tcx, O: fmt::Debug> fmt::Debug for InterpError<'tcx, O> {
                     callee_ty, caller_ty),
             FunctionArgCountMismatch =>
                 write!(f, "tried to call a function with incorrect number of arguments"),
-            BoundsCheck { ref len, ref index } =>
-                write!(f, "index out of bounds: the len is {:?} but the index is {:?}", len, index),
             ReallocatedWrongMemoryKind(ref old, ref new) =>
                 write!(f, "tried to reallocate memory from {} to {}", old, new),
             DeallocatedWrongMemoryKind(ref old, ref new) =>
@@ -518,8 +535,10 @@ impl<'tcx, O: fmt::Debug> fmt::Debug for InterpError<'tcx, O> {
                 write!(f, "incorrect alloc info: expected size {} and align {}, \
                            got size {} and align {}",
                     size.bytes(), align.bytes(), size2.bytes(), align2.bytes()),
-            Panic { ref msg, line, col, ref file } =>
+            Panic(PanicMessage::Panic { ref msg, line, col, ref file }) =>
                 write!(f, "the evaluated program panicked at '{}', {}:{}:{}", msg, file, line, col),
+            Panic(PanicMessage::BoundsCheck { ref len, ref index }) =>
+                write!(f, "index out of bounds: the len is {:?} but the index is {:?}", len, index),
             InvalidDiscriminant(val) =>
                 write!(f, "encountered invalid enum discriminant {}", val),
             Exit(code) =>

src/librustc/mir/interpret/mod.rs

@@ -12,7 +12,7 @@ mod pointer;
 
 pub use self::error::{
     InterpErrorInfo, InterpResult, InterpError, AssertMessage, ConstEvalErr, struct_error,
-    FrameInfo, ConstEvalRawResult, ConstEvalResult, ErrorHandled,
+    FrameInfo, ConstEvalRawResult, ConstEvalResult, ErrorHandled, PanicMessage
 };
 
 pub use self::value::{Scalar, ScalarMaybeUndef, RawConst, ConstValue};

src/librustc/mir/interpret/pointer.rs

@@ -5,7 +5,7 @@ use crate::ty::layout::{self, HasDataLayout, Size};
 use rustc_macros::HashStable;
 
 use super::{
-    AllocId, InterpResult,
+    AllocId, InterpResult, PanicMessage
 };
 
 /// Used by `check_in_alloc` to indicate context of check
@@ -76,13 +76,13 @@ pub trait PointerArithmetic: layout::HasDataLayout {
     #[inline]
     fn offset<'tcx>(&self, val: u64, i: u64) -> InterpResult<'tcx, u64> {
         let (res, over) = self.overflowing_offset(val, i);
-        if over { err!(Overflow(mir::BinOp::Add)) } else { Ok(res) }
+        if over { err!(Panic(PanicMessage::Overflow(mir::BinOp::Add))) } else { Ok(res) }
     }
 
     #[inline]
     fn signed_offset<'tcx>(&self, val: u64, i: i64) -> InterpResult<'tcx, u64> {
         let (res, over) = self.overflowing_signed_offset(val, i128::from(i));
-        if over { err!(Overflow(mir::BinOp::Add)) } else { Ok(res) }
+        if over { err!(Panic(PanicMessage::Overflow(mir::BinOp::Add))) } else { Ok(res) }
     }
 }
 

src/librustc/mir/mod.rs

@@ -7,7 +7,7 @@
 use crate::hir::def::{CtorKind, Namespace};
 use crate::hir::def_id::DefId;
 use crate::hir::{self, InlineAsm as HirInlineAsm};
-use crate::mir::interpret::{ConstValue, InterpError, Scalar};
+use crate::mir::interpret::{ConstValue, PanicMessage, InterpError::Panic, Scalar};
 use crate::mir::visit::MirVisitable;
 use crate::rustc_serialize as serialize;
 use crate::ty::adjustment::PointerCast;
@@ -1931,7 +1931,7 @@ impl<'tcx> Place<'tcx> {
         iterate_over2(place_base, place_projection, &Projections::Empty, op)
     }
 
-    pub fn as_place_ref(&self) -> PlaceRef<'_, 'tcx> {
+    pub fn as_ref(&self) -> PlaceRef<'_, 'tcx> {
         PlaceRef {
             base: &self.base,
             projection: &self.projection,
@@ -3152,11 +3152,11 @@ impl<'tcx> TypeFoldable<'tcx> for Terminator<'tcx> {
                 }
             }
             Assert { ref cond, expected, ref msg, target, cleanup } => {
-                let msg = if let InterpError::BoundsCheck { ref len, ref index } = *msg {
-                    InterpError::BoundsCheck {
+                let msg = if let Panic(PanicMessage::BoundsCheck { ref len, ref index }) = *msg {
+                    Panic(PanicMessage::BoundsCheck {
                         len: len.fold_with(folder),
                         index: index.fold_with(folder),
-                    }
+                    })
                 } else {
                     msg.clone()
                 };
@@ -3197,7 +3197,7 @@ impl<'tcx> TypeFoldable<'tcx> for Terminator<'tcx> {
             }
             Assert { ref cond, ref msg, .. } => {
                 if cond.visit_with(visitor) {
-                    if let InterpError::BoundsCheck { ref len, ref index } = *msg {
+                    if let Panic(PanicMessage::BoundsCheck { ref len, ref index }) = *msg {
                         len.visit_with(visitor) || index.visit_with(visitor)
                     } else {
                         false

src/librustc/mir/visit.rs

@@ -515,7 +515,8 @@ macro_rules! make_mir_visitor {
                                     msg: & $($mutability)? AssertMessage<'tcx>,
                                     location: Location) {
                 use crate::mir::interpret::InterpError::*;
-                if let BoundsCheck { len, index } = msg {
+                use crate::mir::interpret::PanicMessage::BoundsCheck;
+                if let Panic(BoundsCheck { len, index }) = msg {
                     self.visit_operand(len, location);
                     self.visit_operand(index, location);
                 }

src/librustc_allocator/expand.rs

@@ -79,7 +79,7 @@ impl MutVisitor for ExpandAllocatorDirectives<'_> {
 
         if self.found {
             self.handler
-                .span_err(item.span, "cannot define more than one #[global_allocator]");
+                .span_err(item.span, "cannot define more than one `#[global_allocator]`");
             return smallvec![item];
         }
         self.found = true;
@@ -280,7 +280,7 @@ impl AllocFnFactory<'_> {
             AllocatorTy::Unit => (self.cx.ty(self.span, TyKind::Tup(Vec::new())), expr),
 
             AllocatorTy::Layout | AllocatorTy::Usize | AllocatorTy::Ptr => {
-                panic!("can't convert AllocatorTy to an output")
+                panic!("can't convert `AllocatorTy` to an output")
             }
         }
     }

src/librustc_codegen_ssa/mir/analyze.rs

@@ -238,7 +238,7 @@ impl<'mir, 'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> Visitor<'tcx>
                    context: PlaceContext,
                    location: Location) {
         debug!("visit_place(place={:?}, context={:?})", place, context);
-        self.process_place(&place.as_place_ref(), context, location);
+        self.process_place(&place.as_ref(), context, location);
     }
 
     fn visit_local(&mut self,