Auto merge of #50290 - kennytm:rollup, r=kennytm

Rollup of 9 pull requests

Successful merges:

 - #49858 (std: Mark `ptr::Unique` with `#[doc(hidden)]`)
 - #49968 (Stabilize dyn trait)
 - #50192 (Add some utilities to `libsyntax`)
 - #50251 (rustc: Disable threads in LLD for wasm)
 - #50263 (rustc: Emit `uwtable` for allocator shims)
 - #50269 (Update `parking_lot` dependencies)
 - #50273 (Allow #[inline] on closures)
 - #50284 (fix search load page failure)
 - #50257 (Don't ICE on tuple struct ctor with incorrect arg count)

Failed merges:

src/liballoc/boxed.rs

@@ -184,6 +184,7 @@ impl<T: ?Sized> Box<T> {
 
     #[unstable(feature = "ptr_internals", issue = "0", reason = "use into_raw_non_null instead")]
     #[inline]
+    #[doc(hidden)]
     pub fn into_unique(b: Box<T>) -> Unique<T> {
         let unique = b.0;
         mem::forget(b);

src/libcore/ptr.rs

@@ -2513,6 +2513,7 @@ impl<T: ?Sized> PartialOrd for *mut T {
            reason = "use NonNull instead and consider PhantomData<T> \
                      (if you also use #[may_dangle]), Send, and/or Sync")]
 #[allow(deprecated)]
+#[doc(hidden)]
 pub struct Unique<T: ?Sized> {
     pointer: NonZero<*const T>,
     // NOTE: this marker has no consequences for variance, but is necessary

src/libproc_macro/lib.rs

@@ -270,7 +270,7 @@ impl Span {
     /// `self` was generated from, if any.
     #[unstable(feature = "proc_macro", issue = "38356")]
     pub fn parent(&self) -> Option<Span> {
-        self.0.ctxt().outer().expn_info().map(|i| Span(i.call_site))
+        self.0.parent().map(Span)
     }
 
     /// The span for the origin source code that `self` was generated from. If

src/librustc/hir/check_attr.rs

@@ -30,6 +30,7 @@ enum Target {
     ForeignMod,
     Expression,
     Statement,
+    Closure,
     Other,
 }
 
@@ -103,14 +104,14 @@ impl<'a, 'tcx> CheckAttrVisitor<'a, 'tcx> {
         self.check_repr(item, target);
     }
 
-    /// Check if an `#[inline]` is applied to a function.
+    /// Check if an `#[inline]` is applied to a function or a closure.
     fn check_inline(&self, attr: &hir::Attribute, span: &Span, target: Target) {
-        if target != Target::Fn {
+        if target != Target::Fn && target != Target::Closure {
             struct_span_err!(self.tcx.sess,
                              attr.span,
                              E0518,
-                             "attribute should be applied to function")
-                .span_label(*span, "not a function")
+                             "attribute should be applied to function or closure")
+                .span_label(*span, "not a function or closure")
                 .emit();
         }
     }
@@ -286,9 +287,13 @@ impl<'a, 'tcx> CheckAttrVisitor<'a, 'tcx> {
     }
 
     fn check_expr_attributes(&self, expr: &hir::Expr) {
+        let target = match expr.node {
+            hir::ExprClosure(..) => Target::Closure,
+            _ => Target::Expression,
+        };
         for attr in expr.attrs.iter() {
             if attr.check_name("inline") {
-                self.check_inline(attr, &expr.span, Target::Expression);
+                self.check_inline(attr, &expr.span, target);
             }
             if attr.check_name("repr") {
                 self.emit_repr_error(

src/librustc/hir/lowering.rs

@@ -4107,15 +4107,13 @@ impl<'a> LoweringContext<'a> {
     }
 
     fn maybe_lint_bare_trait(&self, span: Span, id: NodeId, is_global: bool) {
-        if self.sess.features_untracked().dyn_trait {
-            self.sess.buffer_lint_with_diagnostic(
-                builtin::BARE_TRAIT_OBJECT,
-                id,
-                span,
-                "trait objects without an explicit `dyn` are deprecated",
-                builtin::BuiltinLintDiagnostics::BareTraitObject(span, is_global),
-            )
-        }
+        self.sess.buffer_lint_with_diagnostic(
+            builtin::BARE_TRAIT_OBJECT,
+            id,
+            span,
+            "trait objects without an explicit `dyn` are deprecated",
+            builtin::BuiltinLintDiagnostics::BareTraitObject(span, is_global),
+        )
     }
 
     fn wrap_in_try_constructor(

src/librustc/lib.rs

@@ -45,8 +45,8 @@
 #![feature(const_fn)]
 #![feature(core_intrinsics)]
 #![feature(drain_filter)]
-#![feature(dyn_trait)]
 #![feature(entry_or_default)]
+#![cfg_attr(stage0, feature(dyn_trait))]
 #![feature(from_ref)]
 #![feature(fs_read_write)]
 #![cfg_attr(windows, feature(libc))]

src/librustc/traits/error_reporting.rs

@@ -979,6 +979,12 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
                      ArgKind::Arg(format!("{}", field.name), "_".to_string())
                  }).collect::<Vec<_>>())
             }
+            hir::map::NodeStructCtor(ref variant_data) => {
+                (self.tcx.sess.codemap().def_span(self.tcx.hir.span(variant_data.id())),
+                 variant_data.fields()
+                    .iter().map(|_| ArgKind::Arg("_".to_owned(), "_".to_owned()))
+                    .collect())
+            }
             _ => panic!("non-FnLike node found: {:?}", node),
         }
     }

src/librustc_mir/lib.rs

@@ -24,7 +24,7 @@ Rust MIR: a lowered representation of Rust. Also: an experiment!
 #![feature(const_fn)]
 #![feature(core_intrinsics)]
 #![feature(decl_macro)]
-#![feature(dyn_trait)]
+#![cfg_attr(stage0, feature(dyn_trait))]
 #![feature(fs_read_write)]
 #![feature(macro_vis_matcher)]
 #![feature(exhaustive_patterns)]

src/librustc_trans/allocator.rs

@@ -11,6 +11,7 @@
 use std::ffi::CString;
 use std::ptr;
 
+use attributes;
 use libc::c_uint;
 use rustc::middle::allocator::AllocatorKind;
 use rustc::ty::TyCtxt;
@@ -67,6 +68,9 @@ pub(crate) unsafe fn trans(tcx: TyCtxt, mods: &ModuleLlvm, kind: AllocatorKind)
         if tcx.sess.target.target.options.default_hidden_visibility {
             llvm::LLVMRustSetVisibility(llfn, llvm::Visibility::Hidden);
         }
+       if tcx.sess.target.target.options.requires_uwtable {
+           attributes::emit_uwtable(llfn, true);
+       }
 
         let callee = CString::new(kind.fn_name(method.name)).unwrap();
         let callee = llvm::LLVMRustGetOrInsertFunction(llmod,

src/librustc_trans/back/linker.rs

@@ -959,7 +959,11 @@ impl Linker for WasmLd {
     }
 
     fn finalize(&mut self) -> Command {
-        self.cmd.arg("--threads");
+        // There have been reports in the wild (rustwasm/wasm-bindgen#119) of
+        // using threads causing weird hangs and bugs. Disable it entirely as
+        // this isn't yet the bottleneck of compilation at all anyway.
+        self.cmd.arg("--no-threads");
+
         self.cmd.arg("-z").arg("stack-size=1048576");
 
         // FIXME we probably shouldn't pass this but instead pass an explicit

src/librustc_typeck/lib.rs

@@ -71,6 +71,8 @@ This API is completely unstable and subject to change.
 
 #![allow(non_camel_case_types)]
 
+#![cfg_attr(stage0, feature(dyn_trait))]
+
 #![feature(box_patterns)]
 #![feature(box_syntax)]
 #![feature(crate_visibility_modifier)]
@@ -81,7 +83,6 @@ This API is completely unstable and subject to change.
 #![feature(rustc_diagnostic_macros)]
 #![feature(slice_patterns)]
 #![feature(slice_sort_by_cached_key)]
-#![feature(dyn_trait)]
 #![feature(never_type)]
 
 #[macro_use] extern crate log;

src/librustdoc/html/layout.rs

@@ -146,9 +146,9 @@ pub fn render<T: fmt::Display, S: fmt::Display>(
         window.rootPath = \"{root_path}\";\
         window.currentCrate = \"{krate}\";\
     </script>\
+    <script src=\"{root_path}aliases.js\"></script>\
     <script src=\"{root_path}main{suffix}.js\"></script>\
     <script defer src=\"{root_path}search-index.js\"></script>\
-    <script defer src=\"{root_path}aliases.js\"></script>\
 </body>\
 </html>",
     css_extension = if css_file_extension {

src/librustdoc/lib.rs

@@ -13,6 +13,8 @@
        html_root_url = "https://doc.rust-lang.org/nightly/",
        html_playground_url = "https://play.rust-lang.org/")]
 
+#![cfg_attr(stage0, feature(dyn_trait))]
+
 #![feature(ascii_ctype)]
 #![feature(rustc_private)]
 #![feature(box_patterns)]
@@ -23,7 +25,6 @@
 #![feature(test)]
 #![feature(vec_remove_item)]
 #![feature(entry_and_modify)]
-#![feature(dyn_trait)]
 
 extern crate arena;
 extern crate getopts;

src/libsyntax/feature_gate.rs

@@ -375,9 +375,6 @@ declare_features! (
     // Future-proofing enums/structs with #[non_exhaustive] attribute (RFC 2008)
     (active, non_exhaustive, "1.22.0", Some(44109), None),
 
-    // Trait object syntax with `dyn` prefix
-    (active, dyn_trait, "1.22.0", Some(44662), Some(Edition::Edition2018)),
-
     // `crate` as visibility modifier, synonymous to `pub(crate)`
     (active, crate_visibility_modifier, "1.23.0", Some(45388), Some(Edition::Edition2018)),
 
@@ -592,6 +589,8 @@ declare_features! (
     (accepted, cfg_target_feature, "1.27.0", Some(29717), None),
     // Allows #[target_feature(...)]
     (accepted, target_feature, "1.27.0", None, None),
+    // Trait object syntax with `dyn` prefix
+    (accepted, dyn_trait, "1.27.0", Some(44662), None),
 );
 
 // If you change this, please modify src/doc/unstable-book as well. You must
@@ -1657,10 +1656,6 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
                 gate_feature_post!(&self, never_type, ty.span,
                                    "The `!` type is experimental");
             }
-            ast::TyKind::TraitObject(_, ast::TraitObjectSyntax::Dyn) => {
-                gate_feature_post!(&self, dyn_trait, ty.span,
-                                   "`dyn Trait` syntax is unstable");
-            }
             _ => {}
         }
         visit::walk_ty(self, ty)

src/libsyntax_pos/hygiene.rs

@@ -21,6 +21,7 @@ use symbol::{Ident, Symbol};
 
 use serialize::{Encodable, Decodable, Encoder, Decoder};
 use std::collections::HashMap;
+use rustc_data_structures::fx::FxHashSet;
 use std::fmt;
 
 /// A SyntaxContext represents a chain of macro expansions (represented by marks).
@@ -117,6 +118,32 @@ impl Mark {
             true
         })
     }
+
+    /// Computes a mark such that both input marks are descendants of (or equal to) the returned
+    /// mark. That is, the following holds:
+    ///
+    /// ```rust
+    /// let la = least_ancestor(a, b);
+    /// assert!(a.is_descendant_of(la))
+    /// assert!(b.is_descendant_of(la))
+    /// ```
+    pub fn least_ancestor(mut a: Mark, mut b: Mark) -> Mark {
+        HygieneData::with(|data| {
+            // Compute the path from a to the root
+            let mut a_path = FxHashSet::<Mark>();
+            while a != Mark::root() {
+                a_path.insert(a);
+                a = data.marks[a.0 as usize].parent;
+            }
+
+            // While the path from b to the root hasn't intersected, move up the tree
+            while !a_path.contains(&b) {
+                b = data.marks[b.0 as usize].parent;
+            }
+
+            b
+        })
+    }
 }
 
 pub struct HygieneData {
@@ -238,6 +265,22 @@ impl SyntaxContext {
         })
     }
 
+    /// Pulls a single mark off of the syntax context. This effectively moves the
+    /// context up one macro definition level. That is, if we have a nested macro
+    /// definition as follows:
+    ///
+    /// ```rust
+    /// macro_rules! f {
+    ///    macro_rules! g {
+    ///        ...
+    ///    }
+    /// }
+    /// ```
+    ///
+    /// and we have a SyntaxContext that is referring to something declared by an invocation
+    /// of g (call it g1), calling remove_mark will result in the SyntaxContext for the
+    /// invocation of f that created g1.
+    /// Returns the mark that was removed.
     pub fn remove_mark(&mut self) -> Mark {
         HygieneData::with(|data| {
             let outer_mark = data.syntax_contexts[self.0 as usize].outer_mark;

src/libsyntax_pos/lib.rs

@@ -291,6 +291,12 @@ impl Span {
         self.ctxt().outer().expn_info().map(|info| info.call_site.source_callsite()).unwrap_or(self)
     }
 
+    /// The `Span` for the tokens in the previous macro expansion from which `self` was generated,
+    /// if any
+    pub fn parent(self) -> Option<Span> {
+        self.ctxt().outer().expn_info().map(|i| i.call_site)
+    }
+
     /// Return the source callee.
     ///
     /// Returns None if the supplied span has no expansion trace,

src/test/compile-fail/attr-usage-inline.rs

@@ -13,7 +13,7 @@
 #[inline]
 fn f() {}
 
-#[inline] //~ ERROR: attribute should be applied to function
+#[inline] //~ ERROR: attribute should be applied to function or closure
 struct S;
 
 fn main() {}

src/test/compile-fail/impl-trait/where-allowed.rs

@@ -10,7 +10,6 @@
 
 //! A simple test for testing many permutations of allowedness of
 //! impl Trait
-#![feature(dyn_trait)]
 use std::fmt::Debug;
 
 // Allowed

src/test/compile-fail/issue-31769.rs

@@ -9,6 +9,6 @@
 // except according to those terms.
 
 fn main() {
-    #[inline] struct Foo;  //~ ERROR attribute should be applied to function
+    #[inline] struct Foo;  //~ ERROR attribute should be applied to function or closure
     #[repr(C)] fn foo() {} //~ ERROR attribute should be applied to struct, enum or union
 }