Auto merge of rust-lang#73635 - Dylan-DPC:rollup-b4wbp42, r=Dylan-DPC

Rollup of 7 pull requests

Successful merges:

 - rust-lang#71756 (add Windows system error codes that should map to io::ErrorKind::TimedOut)
 - rust-lang#73495 (Converted all platform-specific stdin/stdout/stderr implementations to use io:: traits)
 - rust-lang#73575 (Fix typo in error_codes doc)
 - rust-lang#73578 (Make is_freeze and is_copy_modulo_regions take TyCtxtAt)
 - rust-lang#73586 (switch_ty is redundant)
 - rust-lang#73600 (Fix spurious 'value moved here in previous iteration of loop' messages)
 - rust-lang#73610 (Clean up E0699 explanation)

Failed merges:

r? @ghost

Author: bors

src/librustc_codegen_ssa/mir/block.rs

@@ -200,6 +200,8 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         targets: &Vec<mir::BasicBlock>,
     ) {
         let discr = self.codegen_operand(&mut bx, &discr);
+        // `switch_ty` is redundant, sanity-check that.
+        assert_eq!(discr.layout.ty, switch_ty);
         if targets.len() == 2 {
             // If there are two targets, emit br instead of switch
             let lltrue = helper.llblock(self, targets[0]);

src/librustc_codegen_ssa/traits/type_.rs

@@ -74,7 +74,7 @@ pub trait DerivedTypeMethods<'tcx>: BaseTypeMethods<'tcx> + MiscMethods<'tcx> {
     }
 
     fn type_is_freeze(&self, ty: Ty<'tcx>) -> bool {
-        ty.is_freeze(self.tcx(), ty::ParamEnv::reveal_all(), DUMMY_SP)
+        ty.is_freeze(self.tcx().at(DUMMY_SP), ty::ParamEnv::reveal_all())
     }
 
     fn type_has_metadata(&self, ty: Ty<'tcx>) -> bool {

src/librustc_error_codes/error_codes/E0081.md

@@ -1,4 +1,4 @@
-A discrimant value is present more than once.
+A discriminant value is present more than once.
 
 Erroneous code example:
 

src/librustc_error_codes/error_codes/E0699.md

@@ -1,14 +1,16 @@
 A method was called on a raw pointer whose inner type wasn't completely known.
 
-For example, you may have done something like:
+Erroneous code example:
 
-```compile_fail
+```compile_fail,edition2018,E0699
 # #![deny(warnings)]
+# fn main() {
 let foo = &1;
 let bar = foo as *const _;
 if bar.is_null() {
     // ...
 }
+# }
 ```
 
 Here, the type of `bar` isn't known; it could be a pointer to anything. Instead,

src/librustc_lint/builtin.rs

@@ -562,7 +562,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MissingCopyImplementations {
             return;
         }
         let param_env = ty::ParamEnv::empty();
-        if ty.is_copy_modulo_regions(cx.tcx, param_env, item.span) {
+        if ty.is_copy_modulo_regions(cx.tcx.at(item.span), param_env) {
             return;
         }
         if can_type_implement_copy(cx.tcx, param_env, ty).is_ok() {

src/librustc_middle/mir/mod.rs

@@ -1075,6 +1075,8 @@ pub enum TerminatorKind<'tcx> {
         discr: Operand<'tcx>,
 
         /// The type of value being tested.
+        /// This is always the same as the type of `discr`.
+        /// FIXME: remove this redundant information. Currently, it is relied on by pretty-printing.
         switch_ty: Ty<'tcx>,
 
         /// Possible values. The locations to branch to in each case

src/librustc_middle/ty/layout.rs

@@ -2159,7 +2159,7 @@ where
 
             ty::Ref(_, ty, mt) if offset.bytes() == 0 => {
                 let tcx = cx.tcx();
-                let is_freeze = ty.is_freeze(tcx, cx.param_env(), DUMMY_SP);
+                let is_freeze = ty.is_freeze(tcx.at(DUMMY_SP), cx.param_env());
                 let kind = match mt {
                     hir::Mutability::Not => {
                         if is_freeze {

src/librustc_middle/ty/util.rs

@@ -681,11 +681,10 @@ impl<'tcx> ty::TyS<'tcx> {
     /// winds up being reported as an error during NLL borrow check.
     pub fn is_copy_modulo_regions(
         &'tcx self,
-        tcx: TyCtxt<'tcx>,
+        tcx_at: TyCtxtAt<'tcx>,
         param_env: ty::ParamEnv<'tcx>,
-        span: Span,
     ) -> bool {
-        tcx.at(span).is_copy_raw(param_env.and(self))
+        tcx_at.is_copy_raw(param_env.and(self))
     }
 
     /// Checks whether values of this type `T` have a size known at
@@ -706,13 +705,8 @@ impl<'tcx> ty::TyS<'tcx> {
     /// that the `Freeze` trait is not exposed to end users and is
     /// effectively an implementation detail.
     // FIXME: use `TyCtxtAt` instead of separate `Span`.
-    pub fn is_freeze(
-        &'tcx self,
-        tcx: TyCtxt<'tcx>,
-        param_env: ty::ParamEnv<'tcx>,
-        span: Span,
-    ) -> bool {
-        self.is_trivially_freeze() || tcx.at(span).is_freeze_raw(param_env.and(self))
+    pub fn is_freeze(&'tcx self, tcx_at: TyCtxtAt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> bool {
+        self.is_trivially_freeze() || tcx_at.is_freeze_raw(param_env.and(self))
     }
 
     /// Fast path helper for testing if a type is `Freeze`.

src/librustc_mir/borrow_check/diagnostics/conflict_errors.rs

@@ -138,7 +138,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
 
                 let move_msg = if move_spans.for_closure() { " into closure" } else { "" };
 
-                if span == move_span {
+                if location == move_out.source {
                     err.span_label(
                         span,
                         format!("value moved{} here, in previous iteration of loop", move_msg),

src/librustc_mir/dataflow/impls/borrowed_locals.rs

@@ -233,7 +233,7 @@ impl MutBorrow<'mir, 'tcx> {
     ///
     /// [rust-lang/unsafe-code-guidelines#134]: https://github.com/rust-lang/unsafe-code-guidelines/issues/134
     fn shared_borrow_allows_mutation(&self, place: Place<'tcx>) -> bool {
-        !place.ty(self.body, self.tcx).ty.is_freeze(self.tcx, self.param_env, DUMMY_SP)
+        !place.ty(self.body, self.tcx).ty.is_freeze(self.tcx.at(DUMMY_SP), self.param_env)
     }
 }