Rollup merge of rust-lang#22213 - eddyb:ty_open-case-closed, r=nikomatsakis

 This type wasn't necessary, as there was no place using it and unsized types not wrapped in it, at the same time.
r? @nikomatsakis

Author: Manishearth

src/librustc/metadata/tyencode.rs

@@ -153,9 +153,6 @@ pub fn enc_ty<'a, 'tcx>(w: &mut SeekableMemWriter, cx: &ctxt<'a, 'tcx>, t: Ty<'t
         ty::ty_err => {
             mywrite!(w, "e");
         }
-        ty::ty_open(_) => {
-            cx.diag.handler().bug("unexpected type in enc_sty (ty_open)");
-        }
     }
 
     let end = w.tell().unwrap();

src/librustc/middle/fast_reject.rs

@@ -93,7 +93,7 @@ pub fn simplify_type(tcx: &ty::ctxt,
                 None
             }
         }
-        ty::ty_open(_) | ty::ty_infer(_) | ty::ty_err => None,
+        ty::ty_infer(_) | ty::ty_err => None,
     }
 }
 

src/librustc/middle/infer/freshen.rs

@@ -135,7 +135,6 @@ impl<'a, 'tcx> TypeFolder<'tcx> for TypeFreshener<'a, 'tcx> {
                 t
             }
 
-            ty::ty_open(..) |
             ty::ty_bool |
             ty::ty_char |
             ty::ty_int(..) |

src/librustc/middle/traits/coherence.rs

@@ -194,7 +194,6 @@ fn ty_is_local_constructor<'tcx>(tcx: &ty::ctxt<'tcx>, ty: Ty<'tcx>) -> bool {
 
         ty::ty_closure(..) |
         ty::ty_infer(..) |
-        ty::ty_open(..) |
         ty::ty_err => {
             tcx.sess.bug(
                 &format!("ty_is_local invoked on unexpected type: {}",

src/librustc/middle/traits/select.rs

@@ -1626,25 +1626,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                 Ok(AmbiguousBuiltin)
             }
 
-            ty::ty_open(ty) => {
-                // these only crop up in trans, and represent an
-                // "opened" unsized/existential type (one that has
-                // been dereferenced)
-                match bound {
-                    ty::BoundCopy => {
-                        Ok(If(vec!(ty)))
-                    }
-
-                    ty::BoundSized => {
-                        Err(Unimplemented)
-                    }
-
-                    ty::BoundSync |
-                    ty::BoundSend => {
-                        self.tcx().sess.bug("Send/Sync shouldn't occur in builtin_bounds()");
-                    }
-                }
-            }
             ty::ty_err => {
                 Ok(If(Vec::new()))
             }

src/librustc/middle/ty.rs

@@ -930,7 +930,7 @@ impl<'tcx> ctxt<'tcx> {
         sty_debug_print!(
             self,
             ty_enum, ty_uniq, ty_vec, ty_ptr, ty_rptr, ty_bare_fn, ty_trait,
-            ty_struct, ty_closure, ty_tup, ty_param, ty_open, ty_infer, ty_projection);
+            ty_struct, ty_closure, ty_tup, ty_param, ty_infer, ty_projection);
 
         println!("Substs interner: #{}", self.substs_interner.borrow().len());
         println!("BareFnTy interner: #{}", self.bare_fn_interner.borrow().len());
@@ -1374,12 +1374,6 @@ pub enum sty<'tcx> {
     ty_projection(ProjectionTy<'tcx>),
     ty_param(ParamTy), // type parameter
 
-    ty_open(Ty<'tcx>), // A deref'ed fat pointer, i.e., a dynamically sized value
-                       // and its size. Only ever used in trans. It is not necessary
-                       // earlier since we don't need to distinguish a DST with its
-                       // size (e.g., in a deref) vs a DST with the size elsewhere (
-                       // e.g., in a field).
-
     ty_infer(InferTy), // something used only during inference/typeck
     ty_err, // Also only used during inference/typeck, to represent
             // the type of an erroneous expression (helps cut down
@@ -2689,7 +2683,7 @@ impl FlagComputation {
                 self.add_bounds(bounds);
             }
 
-            &ty_uniq(tt) | &ty_vec(tt, _) | &ty_open(tt) => {
+            &ty_uniq(tt) | &ty_vec(tt, _) => {
                 self.add_ty(tt)
             }
 
@@ -2964,8 +2958,6 @@ pub fn mk_param_from_def<'tcx>(cx: &ctxt<'tcx>, def: &TypeParameterDef) -> Ty<'t
     mk_param(cx, def.space, def.index, def.name)
 }
 
-pub fn mk_open<'tcx>(cx: &ctxt<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> { mk_t(cx, ty_open(ty)) }
-
 impl<'tcx> TyS<'tcx> {
     /// Iterator that walks `self` and any types reachable from
     /// `self`, in depth-first order. Note that just walks the types
@@ -3164,7 +3156,6 @@ pub fn sequence_element_type<'tcx>(cx: &ctxt<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
     match ty.sty {
         ty_vec(ty, _) => ty,
         ty_str => mk_mach_uint(cx, ast::TyU8),
-        ty_open(ty) => sequence_element_type(cx, ty),
         _ => cx.sess.bug(&format!("sequence_element_type called on non-sequence value: {}",
                                  ty_to_string(cx, ty))),
     }
@@ -3583,12 +3574,6 @@ pub fn type_contents<'tcx>(cx: &ctxt<'tcx>, ty: Ty<'tcx>) -> TypeContents {
                 TC::All
             }
 
-            ty_open(ty) => {
-                let result = tc_ty(cx, ty, cache);
-                assert!(!result.is_sized(cx));
-                result.unsafe_pointer() | TC::Nonsized
-            }
-
             ty_infer(_) |
             ty_err => {
                 cx.sess.bug("asked to compute contents of error type");
@@ -3747,7 +3732,7 @@ pub fn is_instantiable<'tcx>(cx: &ctxt<'tcx>, r_ty: Ty<'tcx>) -> bool {
             ty_vec(_, None) => {
                 false
             }
-            ty_uniq(typ) | ty_open(typ) => {
+            ty_uniq(typ) => {
                 type_requires(cx, seen, r_ty, typ)
             }
             ty_rptr(_, ref mt) => {
@@ -4106,14 +4091,6 @@ pub fn deref<'tcx>(ty: Ty<'tcx>, explicit: bool) -> Option<mt<'tcx>> {
     }
 }
 
-pub fn close_type<'tcx>(cx: &ctxt<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
-    match ty.sty {
-        ty_open(ty) => mk_rptr(cx, cx.mk_region(ReStatic), mt {ty: ty, mutbl:ast::MutImmutable}),
-        _ => cx.sess.bug(&format!("Trying to close a non-open type {}",
-                                 ty_to_string(cx, ty)))
-    }
-}
-
 pub fn type_content<'tcx>(ty: Ty<'tcx>) -> Ty<'tcx> {
     match ty.sty {
         ty_uniq(ty) => ty,
@@ -4122,14 +4099,6 @@ pub fn type_content<'tcx>(ty: Ty<'tcx>) -> Ty<'tcx> {
     }
 }
 
-// Extract the unsized type in an open type (or just return ty if it is not open).
-pub fn unopen_type<'tcx>(ty: Ty<'tcx>) -> Ty<'tcx> {
-    match ty.sty {
-        ty_open(ty) => ty,
-        _ => ty
-    }
-}
-
 // Returns the type of ty[i]
 pub fn index<'tcx>(ty: Ty<'tcx>) -> Option<Ty<'tcx>> {
     match ty.sty {
@@ -4802,7 +4771,6 @@ pub fn ty_sort_string<'tcx>(cx: &ctxt<'tcx>, ty: Ty<'tcx>) -> String {
             }
         }
         ty_err => "type error".to_string(),
-        ty_open(_) => "opened DST".to_string(),
     }
 }
 
@@ -6328,16 +6296,15 @@ pub fn hash_crate_independent<'tcx>(tcx: &ctxt<'tcx>, ty: Ty<'tcx>, svh: &Svh) -
                     hash!(p.idx);
                     hash!(token::get_name(p.name));
                 }
-                ty_open(_) => byte!(22),
                 ty_infer(_) => unreachable!(),
-                ty_err => byte!(23),
+                ty_err => byte!(21),
                 ty_closure(d, r, _) => {
-                    byte!(24);
+                    byte!(22);
                     did(state, d);
                     region(state, *r);
                 }
                 ty_projection(ref data) => {
-                    byte!(25);
+                    byte!(23);
                     did(state, data.trait_ref.def_id);
                     hash!(token::get_name(data.item_name));
                 }
@@ -6666,7 +6633,6 @@ pub fn accumulate_lifetimes_in_type(accumulator: &mut Vec<ty::Region>,
             ty_projection(_) |
             ty_param(_) |
             ty_infer(_) |
-            ty_open(_) |
             ty_err => {
             }
         }

src/librustc/middle/ty_fold.rs

@@ -626,9 +626,6 @@ pub fn super_fold_ty<'tcx, T: TypeFolder<'tcx>>(this: &mut T,
         ty::ty_vec(typ, sz) => {
             ty::ty_vec(typ.fold_with(this), sz)
         }
-        ty::ty_open(typ) => {
-            ty::ty_open(typ.fold_with(this))
-        }
         ty::ty_enum(tid, ref substs) => {
             let substs = substs.fold_with(this);
             ty::ty_enum(tid, this.tcx().mk_substs(substs))

src/librustc/middle/ty_walk.rs

@@ -28,7 +28,7 @@ impl<'tcx> TypeWalker<'tcx> {
             ty::ty_bool | ty::ty_char | ty::ty_int(_) | ty::ty_uint(_) | ty::ty_float(_) |
             ty::ty_str | ty::ty_infer(_) | ty::ty_param(_) | ty::ty_err => {
             }
-            ty::ty_uniq(ty) | ty::ty_vec(ty, _) | ty::ty_open(ty) => {
+            ty::ty_uniq(ty) | ty::ty_vec(ty, _) => {
                 self.stack.push(ty);
             }
             ty::ty_ptr(ref mt) | ty::ty_rptr(_, ref mt) => {

src/librustc/util/ppaux.rs

@@ -20,7 +20,7 @@ use middle::ty::{ReSkolemized, ReVar, BrEnv};
 use middle::ty::{mt, Ty, ParamTy};
 use middle::ty::{ty_bool, ty_char, ty_struct, ty_enum};
 use middle::ty::{ty_err, ty_str, ty_vec, ty_float, ty_bare_fn};
-use middle::ty::{ty_param, ty_ptr, ty_rptr, ty_tup, ty_open};
+use middle::ty::{ty_param, ty_ptr, ty_rptr, ty_tup};
 use middle::ty::{ty_closure};
 use middle::ty::{ty_uniq, ty_trait, ty_int, ty_uint, ty_infer};
 use middle::ty;
@@ -369,8 +369,6 @@ pub fn ty_to_string<'tcx>(cx: &ctxt<'tcx>, typ: &ty::TyS<'tcx>) -> String {
             buf.push_str(&mt_to_string(cx, tm));
             buf
         }
-        ty_open(typ) =>
-            format!("opened<{}>", ty_to_string(cx, typ)),
         ty_tup(ref elems) => {
             let strs = elems
                 .iter()

src/librustc_trans/trans/_match.rs

@@ -678,7 +678,7 @@ fn bind_subslice_pat(bcx: Block,
 }
 
 fn extract_vec_elems<'blk, 'tcx>(bcx: Block<'blk, 'tcx>,
-                                 left_ty: Ty,
+                                 left_ty: Ty<'tcx>,
                                  before: uint,
                                  after: uint,
                                  val: ValueRef)

src/librustc_trans/trans/adt.rs

@@ -699,7 +699,7 @@ fn struct_llfields<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>, st: &Struct<'tcx>,
         st.fields.iter().filter(|&ty| !dst || type_is_sized(cx.tcx(), *ty))
             .map(|&ty| type_of::sizing_type_of(cx, ty)).collect()
     } else {
-        st.fields.iter().map(|&ty| type_of::type_of(cx, ty)).collect()
+        st.fields.iter().map(|&ty| type_of::in_memory_type_of(cx, ty)).collect()
     }
 }
 

src/librustc_trans/trans/base.rs

@@ -676,8 +676,7 @@ pub fn iter_structural_ty<'blk, 'tcx, F>(cx: Block<'blk, 'tcx>,
                   let val = if common::type_is_sized(cx.tcx(), field_ty) {
                       llfld_a
                   } else {
-                      let boxed_ty = ty::mk_open(cx.tcx(), field_ty);
-                      let scratch = datum::rvalue_scratch_datum(cx, boxed_ty, "__fat_ptr_iter");
+                      let scratch = datum::rvalue_scratch_datum(cx, field_ty, "__fat_ptr_iter");
                       Store(cx, llfld_a, GEPi(cx, scratch.val, &[0, abi::FAT_PTR_ADDR]));
                       Store(cx, info.unwrap(), GEPi(cx, scratch.val, &[0, abi::FAT_PTR_EXTRA]));
                       scratch.val

src/librustc_trans/trans/common.rs

@@ -120,14 +120,16 @@ pub fn erase_regions<'tcx,T>(cx: &ty::ctxt<'tcx>, value: &T) -> T
 // Is the type's representation size known at compile time?
 pub fn type_is_sized<'tcx>(tcx: &ty::ctxt<'tcx>, ty: Ty<'tcx>) -> bool {
     let param_env = ty::empty_parameter_environment(tcx);
-    ty::type_is_sized(&param_env, DUMMY_SP, ty)
-}
-
-pub fn lltype_is_sized<'tcx>(cx: &ty::ctxt<'tcx>, ty: Ty<'tcx>) -> bool {
-    match ty.sty {
-        ty::ty_open(_) => true,
-        _ => type_is_sized(cx, ty),
+    // FIXME(#4287) This can cause errors due to polymorphic recursion,
+    // a better span should be provided, if available.
+    let err_count = tcx.sess.err_count();
+    let is_sized = ty::type_is_sized(&param_env, DUMMY_SP, ty);
+    // Those errors aren't fatal, but an incorrect result can later
+    // trip over asserts in both rustc's trans and LLVM.
+    if err_count < tcx.sess.err_count() {
+        tcx.sess.abort_if_errors();
     }
+    is_sized
 }
 
 pub fn type_is_fat_ptr<'tcx>(cx: &ty::ctxt<'tcx>, ty: Ty<'tcx>) -> bool {
@@ -211,9 +213,7 @@ pub fn type_needs_unwind_cleanup<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, ty: Ty<
     }
 }
 
-pub fn type_needs_drop<'tcx>(cx: &ty::ctxt<'tcx>,
-                         ty: Ty<'tcx>)
-                         -> bool {
+pub fn type_needs_drop<'tcx>(cx: &ty::ctxt<'tcx>, ty: Ty<'tcx>) -> bool {
     ty::type_contents(cx, ty).needs_drop(cx)
 }
 

src/librustc_trans/trans/consts.rs

@@ -146,8 +146,8 @@ fn const_deref<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
                 (const_deref_ptr(cx, v), mt.ty)
             } else {
                 // Derefing a fat pointer does not change the representation,
-                // just the type to ty_open.
-                (v, ty::mk_open(cx.tcx(), mt.ty))
+                // just the type to the unsized contents.
+                (v, mt.ty)
             }
         }
         None => {
@@ -290,15 +290,7 @@ pub fn const_expr<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
                         // an optimisation, it is necessary for mutable vectors to
                         // work properly.
                         ty = match ty::deref(ty, true) {
-                            Some(mt) => {
-                                if type_is_sized(cx.tcx(), mt.ty) {
-                                    mt.ty
-                                } else {
-                                    // Derefing a fat pointer does not change the representation,
-                                    // just the type to ty_open.
-                                    ty::mk_open(cx.tcx(), mt.ty)
-                                }
-                            }
+                            Some(mt) => mt.ty,
                             None => {
                                 cx.sess().bug(&format!("unexpected dereferenceable type {}",
                                                        ty_to_string(cx.tcx(), ty)))
@@ -319,11 +311,12 @@ pub fn const_expr<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
                     llconst = addr_of(cx, llconst, "autoref", e.id);
                 }
                 Some(box ty::AutoUnsize(ref k)) => {
-                    let unsized_ty = ty::unsize_ty(cx.tcx(), ty, k, e.span);
                     let info = expr::unsized_info(cx, k, e.id, ty, param_substs,
                         |t| ty::mk_imm_rptr(cx.tcx(), cx.tcx().mk_region(ty::ReStatic), t));
 
-                    let base = ptrcast(llconst, type_of::type_of(cx, unsized_ty).ptr_to());
+                    let unsized_ty = ty::unsize_ty(cx.tcx(), ty, k, e.span);
+                    let ptr_ty = type_of::in_memory_type_of(cx, unsized_ty).ptr_to();
+                    let base = ptrcast(llconst, ptr_ty);
                     let prev_const = cx.const_unsized().borrow_mut()
                                        .insert(base, llconst);
                     assert!(prev_const.is_none() || prev_const == Some(llconst));
@@ -477,16 +470,10 @@ fn const_expr_unadjusted<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
               };
               let (arr, len) = match bt.sty {
                   ty::ty_vec(_, Some(u)) => (bv, C_uint(cx, u)),
-                  ty::ty_open(ty) => match ty.sty {
-                      ty::ty_vec(_, None) | ty::ty_str => {
-                          let e1 = const_get_elt(cx, bv, &[0]);
-                          (const_deref_ptr(cx, e1), const_get_elt(cx, bv, &[1]))
-                      },
-                      _ => cx.sess().span_bug(base.span,
-                                              &format!("index-expr base must be a vector \
-                                                       or string type, found {}",
-                                                      ty_to_string(cx.tcx(), bt)))
-                  },
+                  ty::ty_vec(_, None) | ty::ty_str => {
+                      let e1 = const_get_elt(cx, bv, &[0]);
+                      (const_deref_ptr(cx, e1), const_get_elt(cx, bv, &[1]))
+                  }
                   ty::ty_rptr(_, mt) => match mt.ty.sty {
                       ty::ty_vec(_, Some(u)) => {
                           (const_deref_ptr(cx, bv), C_uint(cx, u))

src/librustc_trans/trans/datum.rs

@@ -492,8 +492,6 @@ impl<'tcx> Datum<'tcx, Expr> {
                                  -> DatumBlock<'blk, 'tcx, Lvalue> {
         debug!("to_lvalue_datum self: {}", self.to_string(bcx.ccx()));
 
-        assert!(lltype_is_sized(bcx.tcx(), self.ty),
-                "Trying to convert unsized value to lval");
         self.match_kind(
             |l| DatumBlock::new(bcx, l),
             |r| {
@@ -549,15 +547,10 @@ impl<'tcx> Datum<'tcx, Lvalue> {
                                 -> Datum<'tcx, Lvalue> where
         F: FnOnce(ValueRef) -> ValueRef,
     {
-        let val = match self.ty.sty {
-            _ if type_is_sized(bcx.tcx(), self.ty) => gep(self.val),
-            ty::ty_open(_) => {
-                let base = Load(bcx, expr::get_dataptr(bcx, self.val));
-                gep(base)
-            }
-            _ => bcx.tcx().sess.bug(
-                &format!("Unexpected unsized type in get_element: {}",
-                        bcx.ty_to_string(self.ty)))
+        let val = if type_is_sized(bcx.tcx(), self.ty) {
+            gep(self.val)
+        } else {
+            gep(Load(bcx, expr::get_dataptr(bcx, self.val)))
         };
         Datum {
             val: val,
@@ -566,7 +559,8 @@ impl<'tcx> Datum<'tcx, Lvalue> {
         }
     }
 
-    pub fn get_vec_base_and_len(&self, bcx: Block) -> (ValueRef, ValueRef) {
+    pub fn get_vec_base_and_len<'blk>(&self, bcx: Block<'blk, 'tcx>)
+                                      -> (ValueRef, ValueRef) {
         //! Converts a vector into the slice pair.
 
         tvec::get_base_and_len(bcx, self.val, self.ty)