Auto merge of #36393 - petrochenkov:ancient, r=eddyb

Remove some obsolete code from the compiler

src/librustc/middle/mem_categorization.rs

@@ -67,7 +67,6 @@ pub use self::ElementKind::*;
 pub use self::MutabilityCategory::*;
 pub use self::AliasableReason::*;
 pub use self::Note::*;
-pub use self::deref_kind::*;
 
 use self::Aliasability::*;
 
@@ -195,51 +194,6 @@ pub struct cmt_<'tcx> {
 
 pub type cmt<'tcx> = Rc<cmt_<'tcx>>;
 
-// We pun on *T to mean both actual deref of a ptr as well
-// as accessing of components:
-#[derive(Copy, Clone)]
-pub enum deref_kind<'tcx> {
-    deref_ptr(PointerKind<'tcx>),
-    deref_interior(InteriorKind),
-}
-
-type DerefKindContext = Option<InteriorOffsetKind>;
-
-// Categorizes a derefable type.  Note that we include vectors and strings as
-// derefable (we model an index as the combination of a deref and then a
-// pointer adjustment).
-fn deref_kind(t: Ty, context: DerefKindContext) -> McResult<deref_kind> {
-    match t.sty {
-        ty::TyBox(_) => {
-            Ok(deref_ptr(Unique))
-        }
-
-        ty::TyRef(r, mt) => {
-            let kind = ty::BorrowKind::from_mutbl(mt.mutbl);
-            Ok(deref_ptr(BorrowedPtr(kind, r)))
-        }
-
-        ty::TyRawPtr(ref mt) => {
-            Ok(deref_ptr(UnsafePtr(mt.mutbl)))
-        }
-
-        ty::TyAdt(..) => { // newtype
-            Ok(deref_interior(InteriorField(PositionalField(0))))
-        }
-
-        ty::TyArray(..) | ty::TySlice(_) => {
-            // no deref of indexed content without supplying InteriorOffsetKind
-            if let Some(context) = context {
-                Ok(deref_interior(InteriorElement(context, ElementKind::VecElement)))
-            } else {
-                Err(())
-            }
-        }
-
-        _ => Err(()),
-    }
-}
-
 pub trait ast_node {
     fn id(&self) -> ast::NodeId;
     fn span(&self) -> Span;
@@ -476,7 +430,7 @@ impl<'a, 'gcx, 'tcx> MemCategorizationContext<'a, 'gcx, 'tcx> {
                autoderefs,
                cmt);
         for deref in 1..autoderefs + 1 {
-            cmt = self.cat_deref(expr, cmt, deref, None)?;
+            cmt = self.cat_deref(expr, cmt, deref)?;
         }
         return Ok(cmt);
     }
@@ -488,7 +442,7 @@ impl<'a, 'gcx, 'tcx> MemCategorizationContext<'a, 'gcx, 'tcx> {
         match expr.node {
           hir::ExprUnary(hir::UnDeref, ref e_base) => {
             let base_cmt = self.cat_expr(&e_base)?;
-            self.cat_deref(expr, base_cmt, 0, None)
+            self.cat_deref(expr, base_cmt, 0)
           }
 
           hir::ExprField(ref base, f_name) => {
@@ -507,7 +461,6 @@ impl<'a, 'gcx, 'tcx> MemCategorizationContext<'a, 'gcx, 'tcx> {
 
           hir::ExprIndex(ref base, _) => {
             let method_call = ty::MethodCall::expr(expr.id());
-            let context = InteriorOffsetKind::Index;
             match self.infcx.node_method_ty(method_call) {
                 Some(method_ty) => {
                     // If this is an index implemented by a method call, then it
@@ -529,10 +482,10 @@ impl<'a, 'gcx, 'tcx> MemCategorizationContext<'a, 'gcx, 'tcx> {
                     // is an rvalue. That is what we will be
                     // dereferencing.
                     let base_cmt = self.cat_rvalue_node(expr.id(), expr.span(), ret_ty);
-                    self.cat_deref_common(expr, base_cmt, 1, elem_ty, Some(context), true)
+                    Ok(self.cat_deref_common(expr, base_cmt, 1, elem_ty, true))
                 }
                 None => {
-                    self.cat_index(expr, self.cat_expr(&base)?, context)
+                    self.cat_index(expr, self.cat_expr(&base)?, InteriorOffsetKind::Index)
                 }
             }
           }
@@ -907,8 +860,7 @@ impl<'a, 'gcx, 'tcx> MemCategorizationContext<'a, 'gcx, 'tcx> {
     fn cat_deref<N:ast_node>(&self,
                              node: &N,
                              base_cmt: cmt<'tcx>,
-                             deref_cnt: usize,
+                             deref_cnt: usize)
-                             deref_context: DerefKindContext)
                              -> McResult<cmt<'tcx>> {
         let method_call = ty::MethodCall {
             expr_id: node.id(),
@@ -930,12 +882,9 @@ impl<'a, 'gcx, 'tcx> MemCategorizationContext<'a, 'gcx, 'tcx> {
         let base_cmt_ty = base_cmt.ty;
         match base_cmt_ty.builtin_deref(true, ty::NoPreference) {
             Some(mt) => {
-                let ret = self.cat_deref_common(node, base_cmt, deref_cnt,
+                let ret = self.cat_deref_common(node, base_cmt, deref_cnt, mt.ty, false);
-                                              mt.ty,
-                                              deref_context,
-                                                /* implicit: */ false);
                 debug!("cat_deref ret {:?}", ret);
-                ret
+                Ok(ret)
             }
             None => {
                 debug!("Explicit deref of non-derefable type: {:?}",
@@ -950,40 +899,29 @@ impl<'a, 'gcx, 'tcx> MemCategorizationContext<'a, 'gcx, 'tcx> {
                                     base_cmt: cmt<'tcx>,
                                     deref_cnt: usize,
                                     deref_ty: Ty<'tcx>,
-                                    deref_context: DerefKindContext,
                                     implicit: bool)
-                                    -> McResult<cmt<'tcx>>
+                                    -> cmt<'tcx>
     {
-        let (m, cat) = match deref_kind(base_cmt.ty, deref_context)? {
+        let ptr = match base_cmt.ty.sty {
-            deref_ptr(ptr) => {
+            ty::TyBox(..) => Unique,
-                let ptr = if implicit {
+            ty::TyRawPtr(ref mt) => UnsafePtr(mt.mutbl),
-                    match ptr {
+            ty::TyRef(r, mt) => {
-                        BorrowedPtr(bk, r) => Implicit(bk, r),
+                let bk = ty::BorrowKind::from_mutbl(mt.mutbl);
-                        _ => span_bug!(node.span(),
+                if implicit { Implicit(bk, r) } else { BorrowedPtr(bk, r) }
-                            "Implicit deref of non-borrowed pointer")
-                    }
-                } else {
-                    ptr
-                };
-                // for unique ptrs, we inherit mutability from the
-                // owning reference.
-                (MutabilityCategory::from_pointer_kind(base_cmt.mutbl, ptr),
-                 Categorization::Deref(base_cmt, deref_cnt, ptr))
-            }
-            deref_interior(interior) => {
-                (base_cmt.mutbl.inherit(), Categorization::Interior(base_cmt, interior))
             }
+            ref ty => bug!("unexpected type in cat_deref_common: {:?}", ty)
         };
         let ret = Rc::new(cmt_ {
             id: node.id(),
             span: node.span(),
-            cat: cat,
+            // For unique ptrs, we inherit mutability from the owning reference.
-            mutbl: m,
+            mutbl: MutabilityCategory::from_pointer_kind(base_cmt.mutbl, ptr),
+            cat: Categorization::Deref(base_cmt, deref_cnt, ptr),
             ty: deref_ty,
             note: NoteNone
         });
         debug!("cat_deref_common ret {:?}", ret);
-        Ok(ret)
+        ret
     }
 
     pub fn cat_index<N:ast_node>(&self,
@@ -1206,7 +1144,7 @@ impl<'a, 'gcx, 'tcx> MemCategorizationContext<'a, 'gcx, 'tcx> {
             // box p1, &p1, &mut p1.  we can ignore the mutability of
             // PatKind::Ref since that information is already contained
             // in the type.
-            let subcmt = self.cat_deref(pat, cmt, 0, None)?;
+            let subcmt = self.cat_deref(pat, cmt, 0)?;
             self.cat_pattern_(subcmt, &subpat, op)?;
           }
 

src/librustc_metadata/encoder.rs

@@ -252,27 +252,6 @@ impl<'a, 'tcx, 'encoder> ItemContentBuilder<'a, 'tcx, 'encoder> {
     }
 }
 
-/// Iterates through "auxiliary node IDs", which are node IDs that describe
-/// top-level items that are sub-items of the given item. Specifically:
-///
-/// * For newtype structs, iterates through the node ID of the constructor.
-fn each_auxiliary_node_id<F>(item: &hir::Item, callback: F) -> bool where
-    F: FnOnce(NodeId) -> bool,
-{
-    let mut continue_ = true;
-    match item.node {
-        hir::ItemStruct(ref struct_def, _) => {
-            // If this is a newtype struct, return the constructor.
-            if struct_def.is_tuple() {
-                continue_ = callback(struct_def.id());
-            }
-        }
-        _ => {}
-    }
-
-    continue_
-}
-
 fn encode_reexports(ecx: &EncodeContext,
                     rbml_w: &mut Encoder,
                     id: NodeId) {
@@ -313,13 +292,6 @@ impl<'a, 'tcx, 'encoder> ItemContentBuilder<'a, 'tcx, 'encoder> {
         for item_id in &md.item_ids {
             self.rbml_w.wr_tagged_u64(tag_mod_child,
                                  def_to_u64(ecx.tcx.map.local_def_id(item_id.id)));
-
-            let item = ecx.tcx.map.expect_item(item_id.id);
-            each_auxiliary_node_id(item, |auxiliary_node_id| {
-                self.rbml_w.wr_tagged_u64(tag_mod_child,
-                                     def_to_u64(ecx.tcx.map.local_def_id(auxiliary_node_id)));
-                true
-            });
         }
 
         self.encode_visibility(vis);

src/librustc_resolve/build_reduced_graph.rs

@@ -261,8 +261,8 @@ impl<'b> Resolver<'b> {
                 let def = Def::Struct(self.definitions.local_def_id(item.id));
                 self.define(parent, name, TypeNS, (def, sp, vis));
 
-                // If this is a newtype or unit-like struct, define a name
+                // If this is a tuple or unit struct, define a name
-                // in the value namespace as well
+                // in the value namespace as well.
                 if !struct_def.is_struct() {
                     let def = Def::Struct(self.definitions.local_def_id(struct_def.id()));
                     self.define(parent, name, ValueNS, (def, sp, vis));

src/librustc_trans/adt.rs

@@ -231,7 +231,7 @@ fn represent_type_uncached<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
                 }
 
                 if cases.len() == 1 && hint == attr::ReprAny {
-                    // Equivalent to a struct/tuple/newtype.
+                    // Equivalent to a struct or tuple.
                     return Univariant(mk_struct(cx, &cases[0].tys, false, t));
                 }
 

src/librustdoc/clean/inline.rs

@@ -19,7 +19,7 @@ use rustc::middle::cstore;
 use rustc::hir::def::Def;
 use rustc::hir::def_id::DefId;
 use rustc::hir::print as pprust;
-use rustc::ty::{self, TyCtxt};
+use rustc::ty::{self, TyCtxt, VariantKind};
 use rustc::util::nodemap::FnvHashSet;
 
 use rustc_const_eval::lookup_const_by_id;
@@ -207,11 +207,10 @@ fn build_struct<'a, 'tcx>(cx: &DocContext, tcx: TyCtxt<'a, 'tcx, 'tcx>,
     let variant = tcx.lookup_adt_def(did).struct_variant();
 
     clean::Struct {
-        struct_type: match &variant.fields[..] {
+        struct_type: match variant.kind {
-            &[] => doctree::Unit,
+            VariantKind::Struct => doctree::Plain,
-            &[_] if variant.kind == ty::VariantKind::Tuple => doctree::Newtype,
+            VariantKind::Tuple => doctree::Tuple,
-            &[..] if variant.kind == ty::VariantKind::Tuple => doctree::Tuple,
+            VariantKind::Unit => doctree::Unit,
-            _ => doctree::Plain,
         },
         generics: (t.generics, &predicates).clean(cx),
         fields: variant.fields.clean(cx),

src/librustdoc/doctree.rs

@@ -82,14 +82,12 @@ impl Module {
 
 #[derive(Debug, Clone, RustcEncodable, RustcDecodable, Copy)]
 pub enum StructType {
-    /// A normal struct
+    /// A braced struct
     Plain,
     /// A tuple struct
     Tuple,
-    /// A newtype struct (tuple struct with one element)
-    Newtype,
     /// A unit struct
-    Unit
+    Unit,
 }
 
 pub enum TypeBound {
@@ -262,15 +260,10 @@ pub struct Import {
     pub whence: Span,
 }
 
-pub fn struct_type_from_def(sd: &hir::VariantData) -> StructType {
+pub fn struct_type_from_def(vdata: &hir::VariantData) -> StructType {
-    if !sd.is_struct() {
+    match *vdata {
-        // We are in a tuple-struct
+        hir::VariantData::Struct(..) => Plain,
-        match sd.fields().len() {
+        hir::VariantData::Tuple(..) => Tuple,
-            0 => Unit,
+        hir::VariantData::Unit(..) => Unit,
-            1 => Newtype,
-            _ => Tuple
-        }
-    } else {
-        Plain
     }
 }

src/librustdoc/html/render.rs

@@ -2546,7 +2546,7 @@ fn render_struct(w: &mut fmt::Formatter, it: &clean::Item,
             }
             write!(w, "}}")?;
         }
-        doctree::Tuple | doctree::Newtype => {
+        doctree::Tuple => {
             write!(w, "(")?;
             for (i, field) in fields.iter().enumerate() {
                 if i > 0 {

src/libsyntax/parse/obsolete.rs

@@ -19,8 +19,7 @@ use parse::parser;
 /// The specific types of unsupported syntax
 #[derive(Copy, Clone, PartialEq, Eq, Hash)]
 pub enum ObsoleteSyntax {
-    ClosureKind,
+    // Nothing here at the moment
-    ExternCrateString,
 }
 
 pub trait ParserObsoleteMethods {
@@ -36,18 +35,10 @@ pub trait ParserObsoleteMethods {
 
 impl<'a> ParserObsoleteMethods for parser::Parser<'a> {
     /// Reports an obsolete syntax non-fatal error.
+    #[allow(unused_variables)]
     fn obsolete(&mut self, sp: Span, kind: ObsoleteSyntax) {
         let (kind_str, desc, error) = match kind {
-            ObsoleteSyntax::ClosureKind => (
+            // Nothing here at the moment
-                "`:`, `&mut:`, or `&:`",
-                "rely on inference instead",
-                true,
-            ),
-            ObsoleteSyntax::ExternCrateString => (
-                "\"crate-name\"",
-                "use an identifier not in quotes instead",
-                false, // warning for now
-            ),
         };
 
         self.report(sp, kind, kind_str, desc, error);

src/libsyntax/parse/parser.rs

@@ -47,7 +47,7 @@ use parse;
 use parse::classify;
 use parse::common::SeqSep;
 use parse::lexer::{Reader, TokenAndSpan};
-use parse::obsolete::{ParserObsoleteMethods, ObsoleteSyntax};
+use parse::obsolete::ObsoleteSyntax;
 use parse::token::{self, intern, MatchNt, SubstNt, SpecialVarNt, InternedString};
 use parse::token::{keywords, SpecialMacroVar};
 use parse::{new_sub_parser_from_file, ParseSess};
@@ -1165,36 +1165,6 @@ impl<'a> Parser<'a> {
         })))
     }
 
-    /// Parses an obsolete closure kind (`&:`, `&mut:`, or `:`).
-    pub fn parse_obsolete_closure_kind(&mut self) -> PResult<'a, ()> {
-         let lo = self.span.lo;
-        if
-            self.check(&token::BinOp(token::And)) &&
-            self.look_ahead(1, |t| t.is_keyword(keywords::Mut)) &&
-            self.look_ahead(2, |t| *t == token::Colon)
-        {
-            self.bump();
-            self.bump();
-            self.bump();
-        } else if
-            self.token == token::BinOp(token::And) &&
-            self.look_ahead(1, |t| *t == token::Colon)
-        {
-            self.bump();
-            self.bump();
-        } else if
-            self.eat(&token::Colon)
-        {
-            /* nothing */
-        } else {
-            return Ok(());
-        }
-
-        let span = mk_sp(lo, self.span.hi);
-        self.obsolete(span, ObsoleteSyntax::ClosureKind);
-        Ok(())
-    }
-
     pub fn parse_unsafety(&mut self) -> PResult<'a, Unsafety> {
         if self.eat_keyword(keywords::Unsafe) {
             return Ok(Unsafety::Unsafe);
@@ -4728,7 +4698,6 @@ impl<'a> Parser<'a> {
                 Vec::new()
             } else {
                 self.expect(&token::BinOp(token::Or))?;
-                self.parse_obsolete_closure_kind()?;
                 let args = self.parse_seq_to_before_end(
                     &token::BinOp(token::Or),
                     SeqSep::trailing_allowed(token::Comma),

src/test/parse-fail/obsolete-closure-kind.rs

@@ -1,18 +0,0 @@
-// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-// Test that we generate obsolete syntax errors around usages of closure kinds: `|:|`, `|&:|` and
-// `|&mut:|`.
-
-fn main() {
-    let a = |:| {};  //~ ERROR obsolete syntax: `:`, `&mut:`, or `&:`
-    let a = |&:| {};  //~ ERROR obsolete syntax: `:`, `&mut:`, or `&:`
-    let a = |&mut:| {};  //~ ERROR obsolete syntax: `:`, `&mut:`, or `&:`
-}