Rollup of 10 pull requests

RELEASES.md

@@ -10,7 +10,7 @@ Language
   function's caller's location information for panic messages.][72445]
 - [Recursively indexing into tuples no longer needs parentheses.][71322] E.g.
   `x.0.0` over `(x.0).0`.
-- [`mem::transmute` can now be used in static and constants.][72920] **Note**
+- [`mem::transmute` can now be used in statics and constants.][72920] **Note**
   You currently can't use `mem::transmute` in constant functions.
 
 Compiler

library/core/src/ptr/non_null.rs

@@ -34,8 +34,8 @@ use crate::slice::{self, SliceIndex};
 /// it is your responsibility to ensure that `as_mut` is never called, and `as_ptr`
 /// is never used for mutation.
 ///
-/// [`PhantomData`]: ../marker/struct.PhantomData.html
-/// [`UnsafeCell<T>`]: ../cell/struct.UnsafeCell.html
+/// [`PhantomData`]: crate::marker::PhantomData
+/// [`UnsafeCell<T>`]: crate::cell::UnsafeCell
 #[stable(feature = "nonnull", since = "1.25.0")]
 #[repr(transparent)]
 #[rustc_layout_scalar_valid_range_start(1)]
@@ -82,8 +82,8 @@ impl<T: Sized> NonNull<T> {
     ///
     /// For the mutable counterpart see [`as_uninit_mut`].
     ///
-    /// [`as_ref`]: #method.as_ref
-    /// [`as_uninit_mut`]: #method.as_uninit_mut
+    /// [`as_ref`]: NonNull::as_ref
+    /// [`as_uninit_mut`]: NonNull::as_uninit_mut
     ///
     /// # Safety
     ///
@@ -114,8 +114,8 @@ impl<T: Sized> NonNull<T> {
     ///
     /// For the shared counterpart see [`as_uninit_ref`].
     ///
-    /// [`as_mut`]: #method.as_mut
-    /// [`as_uninit_ref`]: #method.as_uninit_ref
+    /// [`as_mut`]: NonNull::as_mut
+    /// [`as_uninit_ref`]: NonNull::as_uninit_ref
     ///
     /// # Safety
     ///
@@ -181,8 +181,8 @@ impl<T: ?Sized> NonNull<T> {
     ///
     /// For the mutable counterpart see [`as_mut`].
     ///
-    /// [`as_uninit_ref`]: #method.as_uninit_ref
-    /// [`as_mut`]: #method.as_mut
+    /// [`as_uninit_ref`]: NonNull::as_uninit_ref
+    /// [`as_mut`]: NonNull::as_mut
     ///
     /// # Safety
     ///
@@ -217,8 +217,8 @@ impl<T: ?Sized> NonNull<T> {
     ///
     /// For the shared counterpart see [`as_ref`].
     ///
-    /// [`as_uninit_mut`]: #method.as_uninit_mut
-    /// [`as_ref`]: #method.as_ref
+    /// [`as_uninit_mut`]: NonNull::as_uninit_mut
+    /// [`as_ref`]: NonNull::as_ref
     ///
     /// # Safety
     ///
@@ -266,8 +266,6 @@ impl<T> NonNull<[T]> {
     /// This function is safe, but dereferencing the return value is unsafe.
     /// See the documentation of [`slice::from_raw_parts`] for slice safety requirements.
     ///
-    /// [`slice::from_raw_parts`]: ../../std/slice/fn.from_raw_parts.html
-    ///
     /// # Examples
     ///
     /// ```rust
@@ -357,8 +355,8 @@ impl<T> NonNull<[T]> {
     ///
     /// For the mutable counterpart see [`as_uninit_slice_mut`].
     ///
-    /// [`as_ref`]: #method.as_ref
-    /// [`as_uninit_slice_mut`]: #method.as_uninit_slice_mut
+    /// [`as_ref`]: NonNull::as_ref
+    /// [`as_uninit_slice_mut`]: NonNull::as_uninit_slice_mut
     ///
     /// # Safety
     ///
@@ -386,10 +384,9 @@ impl<T> NonNull<[T]> {
     ///
     /// This applies even if the result of this method is unused!
     ///
-    /// See also [`slice::from_raw_parts`][].
+    /// See also [`slice::from_raw_parts`].
     ///
     /// [valid]: crate::ptr#safety
-    /// [`NonNull::dangling()`]: NonNull::dangling
     /// [`pointer::offset`]: ../../std/primitive.pointer.html#method.offset
     #[inline]
     #[unstable(feature = "ptr_as_uninit", issue = "75402")]
@@ -403,8 +400,8 @@ impl<T> NonNull<[T]> {
     ///
     /// For the shared counterpart see [`as_uninit_slice`].
     ///
-    /// [`as_mut`]: #method.as_mut
-    /// [`as_uninit_slice`]: #method.as_uninit_slice
+    /// [`as_mut`]: NonNull::as_mut
+    /// [`as_uninit_slice`]: NonNull::as_uninit_slice
     ///
     /// # Safety
     ///
@@ -432,10 +429,9 @@ impl<T> NonNull<[T]> {
     ///
     /// This applies even if the result of this method is unused!
     ///
-    /// See also [`slice::from_raw_parts_mut`][].
+    /// See also [`slice::from_raw_parts_mut`].
     ///
     /// [valid]: crate::ptr#safety
-    /// [`NonNull::dangling()`]: NonNull::dangling
     /// [`pointer::offset`]: ../../std/primitive.pointer.html#method.offset
     ///
     /// # Examples

src/doc/rustc/src/platform-support.md

@@ -118,7 +118,7 @@ target | std | host | notes
 `thumbv7neon-unknown-linux-gnueabihf` | ✓ |  | Thumb2-mode ARMv7a Linux with NEON (kernel 4.4, glibc 2.23)
 `thumbv8m.base-none-eabi` | * |  | ARMv8-M Baseline
 `thumbv8m.main-none-eabi` | * |  | ARMv8-M Mainline
-`thumbv8m.main-none-eabihf` | * |  | ARMv8-M Baseline, hardfloat
+`thumbv8m.main-none-eabihf` | * |  | ARMv8-M Mainline, hardfloat
 `wasm32-unknown-emscripten` | ✓ |  | WebAssembly via Emscripten
 `wasm32-unknown-unknown` | ✓ |  | WebAssembly
 `wasm32-wasi` | ✓ |  | WebAssembly with WASI

src/doc/unstable-book/src/compiler-flags/tls-model.md

@@ -22,4 +22,4 @@ The TLS data must not be in a library loaded after startup (via `dlopen`).
 but not in a shared library, and is accessed only from that executable.
 
 `rustc` and LLVM may use a more optimized model than specified if they know that we are producing
-and executable rather than a library, or that the `static` item is private enough.
+an executable rather than a library, or that the `static` item is private enough.

src/librustc_lint/builtin.rs

@@ -38,6 +38,7 @@ use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::DefId;
 use rustc_hir::{ForeignItemKind, GenericParamKind, PatKind};
 use rustc_hir::{HirId, HirIdSet, Node};
+use rustc_index::vec::Idx;
 use rustc_middle::lint::LintDiagnosticBuilder;
 use rustc_middle::ty::subst::{GenericArgKind, Subst};
 use rustc_middle::ty::{self, layout::LayoutError, Ty, TyCtxt};
@@ -2162,6 +2163,40 @@ impl ClashingExternDeclarations {
             ckind: CItemKind,
         ) -> bool {
             debug!("structurally_same_type_impl(cx, a = {:?}, b = {:?})", a, b);
+            let tcx = cx.tcx;
+
+            // Given a transparent newtype, reach through and grab the inner
+            // type unless the newtype makes the type non-null.
+            let non_transparent_ty = |ty: Ty<'tcx>| -> Ty<'tcx> {
+                let mut ty = ty;
+                loop {
+                    if let ty::Adt(def, substs) = ty.kind {
+                        let is_transparent = def.subst(tcx, substs).repr.transparent();
+                        let is_non_null = crate::types::nonnull_optimization_guaranteed(tcx, &def);
+                        debug!(
+                            "non_transparent_ty({:?}) -- type is transparent? {}, type is non-null? {}",
+                            ty, is_transparent, is_non_null
+                        );
+                        if is_transparent && !is_non_null {
+                            debug_assert!(def.variants.len() == 1);
+                            let v = &def.variants[VariantIdx::new(0)];
+                            ty = v
+                                .transparent_newtype_field(tcx)
+                                .expect(
+                                    "single-variant transparent structure with zero-sized field",
+                                )
+                                .ty(tcx, substs);
+                            continue;
+                        }
+                    }
+                    debug!("non_transparent_ty -> {:?}", ty);
+                    return ty;
+                }
+            };
+
+            let a = non_transparent_ty(a);
+            let b = non_transparent_ty(b);
+
             if !seen_types.insert((a, b)) {
                 // We've encountered a cycle. There's no point going any further -- the types are
                 // structurally the same.

src/librustc_lint/types.rs

@@ -11,7 +11,7 @@ use rustc_index::vec::Idx;
 use rustc_middle::mir::interpret::{sign_extend, truncate};
 use rustc_middle::ty::layout::{IntegerExt, SizeSkeleton};
 use rustc_middle::ty::subst::SubstsRef;
-use rustc_middle::ty::{self, AdtKind, Ty, TypeFoldable};
+use rustc_middle::ty::{self, AdtKind, Ty, TyCtxt, TypeFoldable};
 use rustc_span::source_map;
 use rustc_span::symbol::sym;
 use rustc_span::{Span, DUMMY_SP};
@@ -527,22 +527,26 @@ enum FfiResult<'tcx> {
     FfiUnsafe { ty: Ty<'tcx>, reason: String, help: Option<String> },
 }
 
+crate fn nonnull_optimization_guaranteed<'tcx>(tcx: TyCtxt<'tcx>, def: &ty::AdtDef) -> bool {
+    tcx.get_attrs(def.did)
+        .iter()
+        .any(|a| tcx.sess.check_name(a, sym::rustc_nonnull_optimization_guaranteed))
+}
+
 /// Is type known to be non-null?
-fn ty_is_known_nonnull<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, mode: CItemKind) -> bool {
+crate fn ty_is_known_nonnull<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, mode: CItemKind) -> bool {
     let tcx = cx.tcx;
     match ty.kind {
         ty::FnPtr(_) => true,
         ty::Ref(..) => true,
         ty::Adt(def, _) if def.is_box() && matches!(mode, CItemKind::Definition) => true,
         ty::Adt(def, substs) if def.repr.transparent() && !def.is_union() => {
-            let guaranteed_nonnull_optimization = tcx
-                .get_attrs(def.did)
-                .iter()
-                .any(|a| tcx.sess.check_name(a, sym::rustc_nonnull_optimization_guaranteed));
+            let marked_non_null = nonnull_optimization_guaranteed(tcx, &def);
 
-            if guaranteed_nonnull_optimization {
+            if marked_non_null {
                 return true;
             }
+
             for variant in &def.variants {
                 if let Some(field) = variant.transparent_newtype_field(tcx) {
                     if ty_is_known_nonnull(cx, field.ty(tcx, substs), mode) {

src/librustc_typeck/check/expr.rs

@@ -1545,13 +1545,17 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 normalized_ty.kind,
             );
             if let ty::Adt(def, _) = normalized_ty.kind {
-                if def.non_enum_variant().fields.iter().any(|field| field.ident == field_ident) {
-                    err.span_suggestion_verbose(
-                        base.span.shrink_to_hi(),
-                        "consider awaiting before field access",
-                        ".await".to_string(),
-                        Applicability::MaybeIncorrect,
-                    );
+                // no field access on enum type
+                if !def.is_enum() {
+                    if def.non_enum_variant().fields.iter().any(|field| field.ident == field_ident)
+                    {
+                        err.span_suggestion_verbose(
+                            base.span.shrink_to_hi(),
+                            "consider awaiting before field access",
+                            ".await".to_string(),
+                            Applicability::MaybeIncorrect,
+                        );
+                    }
                 }
             }
         }

src/librustdoc/html/static/main.js

@@ -344,6 +344,7 @@ function defocusSearchBar() {
     }
 
     function getHelpElement() {
+        buildHelperPopup();
         return document.getElementById("help");
     }
 
@@ -2807,8 +2808,8 @@ function defocusSearchBar() {
 
         var infos = [
             "Prefix searches with a type followed by a colon (e.g., <code>fn:</code>) to \
-             restrict the search to a given type.",
-            "Accepted types are: <code>fn</code>, <code>mod</code>, <code>struct</code>, \
+             restrict the search to a given item kind.",
+            "Accepted kinds are: <code>fn</code>, <code>mod</code>, <code>struct</code>, \
              <code>enum</code>, <code>trait</code>, <code>type</code>, <code>macro</code>, \
              and <code>const</code>.",
             "Search functions by type signature (e.g., <code>vec -&gt; usize</code> or \
@@ -2828,12 +2829,12 @@ function defocusSearchBar() {
 
         popup.appendChild(container);
         insertAfter(popup, getSearchElement());
+        // So that it's only built once and then it'll do nothing when called!
+        buildHelperPopup = function() {};
     }
 
     onHashChange(null);
     window.onhashchange = onHashChange;
-
-    buildHelperPopup();
 }());
 
 // This is required in firefox. Explanations: when going back in the history, firefox doesn't re-run

src/librustdoc/html/static/rustdoc.css

@@ -1290,7 +1290,7 @@ h4 > .notable-traits {
 #theme-choices > button {
 	border: none;
 	width: 100%;
-	padding: 4px;
+	padding: 4px 8px;
 	text-align: center;
 	background: rgba(0,0,0,0);
 }

src/librustdoc/html/static/themes/ayu.css

@@ -518,7 +518,7 @@ kbd {
 }
 
 #theme-choices > button:hover, #theme-choices > button:focus {
-	background-color: rgba(70, 70, 70, 0.33);
+	background-color: rgba(110, 110, 110, 0.33);
 }
 
 @media (max-width: 700px) {

src/test/codegen/issue-27130.rs

@@ -0,0 +1,22 @@
+// compile-flags: -O
+// min-llvm-version: 11.0
+
+#![crate_type = "lib"]
+
+// CHECK-LABEL: @trim_in_place
+#[no_mangle]
+pub fn trim_in_place(a: &mut &[u8]) {
+    while a.first() == Some(&42) {
+        // CHECK-NOT: slice_index_order_fail
+        *a = &a[1..];
+    }
+}
+
+// CHECK-LABEL: @trim_in_place2
+#[no_mangle]
+pub fn trim_in_place2(a: &mut &[u8]) {
+    while let Some(&42) = a.first() {
+        // CHECK-NOT: slice_index_order_fail
+        *a = &a[1..];
+    }
+}