auto merge of #6148 : erickt/rust/remove-drop, r=pcwalton

The drop block has been deprecated for quite some time. This patch series removes support for parsing it and all the related machinery that made drop work.

As a side feature of all this, I also added the ability to annote fields in structs. This allows comments to be properly associated with an individual field. However, I didn't update `rustdoc` to integrate these comment blocks into the documentation it generates.

Author: bors

src/compiletest/header.rs

@@ -82,14 +82,13 @@ pub fn load_props(testfile: &Path) -> TestProps {
 }
 
 pub fn is_test_ignored(config: config, testfile: &Path) -> bool {
-    let mut found = false;
     for iter_header(testfile) |ln| {
         if parse_name_directive(ln, ~"xfail-test") { return true; }
         if parse_name_directive(ln, xfail_target()) { return true; }
         if config.mode == common::mode_pretty &&
            parse_name_directive(ln, ~"xfail-pretty") { return true; }
     };
-    return found;
+    return true;
 
     fn xfail_target() -> ~str {
         ~"xfail-" + str::from_slice(os::SYSNAME)

src/compiletest/runtest.rs

@@ -106,7 +106,7 @@ fn run_rpass_test(config: config, props: TestProps, testfile: &Path) {
             fatal_ProcRes(~"test run failed!", ProcRes);
         }
     } else {
-        let mut ProcRes = jit_test(config, props, testfile);
+        let ProcRes = jit_test(config, props, testfile);
 
         if ProcRes.status != 0 { fatal_ProcRes(~"jit failed!", ProcRes); }
     }

src/libcore/core.rc

@@ -63,7 +63,6 @@ they contained the following prologue:
 #[warn(vecs_implicitly_copyable)];
 #[deny(non_camel_case_types)];
 #[allow(deprecated_mutable_fields)];
-#[allow(deprecated_drop)];
 
 // Make core testable by not duplicating lang items. See #2912
 #[cfg(test)] extern mod realcore(name = "core", vers = "0.7-pre");

src/libcore/pipes.rs

@@ -86,7 +86,9 @@ use cast::{forget, transmute, transmute_copy};
 use either::{Either, Left, Right};
 use kinds::Owned;
 use libc;
+use ops::Drop;
 use option::{None, Option, Some};
+use unstable::finally::Finally;
 use unstable::intrinsics;
 use ptr;
 use task;
@@ -395,26 +397,22 @@ pub fn try_recv<T:Owned,Tbuffer:Owned>(p: RecvPacketBuffered<T, Tbuffer>)
     let p_ = p.unwrap();
     let p = unsafe { &*p_ };
 
-    #[unsafe_destructor]
-    struct DropState<'self> {
-        p: &'self PacketHeader,
-
-        drop {
-            unsafe {
-                if task::failing() {
-                    self.p.state = Terminated;
-                    let old_task = swap_task(&mut self.p.blocked_task,
-                                             ptr::null());
-                    if !old_task.is_null() {
-                        rustrt::rust_task_deref(old_task);
-                    }
+    do (|| {
+        try_recv_(p)
+    }).finally {
+        unsafe {
+            if task::failing() {
+                p.header.state = Terminated;
+                let old_task = swap_task(&mut p.header.blocked_task, ptr::null());
+                if !old_task.is_null() {
+                    rustrt::rust_task_deref(old_task);
                 }
             }
         }
-    };
-
-    let _drop_state = DropState { p: &p.header };
+    }
+}
 
+fn try_recv_<T:Owned>(p: &Packet<T>) -> Option<T> {
     // optimistic path
     match p.header.state {
       Full => {
@@ -451,7 +449,7 @@ pub fn try_recv<T:Owned,Tbuffer:Owned>(p: RecvPacketBuffered<T, Tbuffer>)
                                        Blocked);
         match old_state {
           Empty => {
-            debug!("no data available on %?, going to sleep.", p_);
+            debug!("no data available on %?, going to sleep.", p);
             if count == 0 {
                 wait_event(this);
             }

src/librustc/metadata/common.rs

@@ -100,7 +100,6 @@ pub static tag_mod_impl_trait: uint = 0x47u;
   different tags.
  */
 pub static tag_item_impl_method: uint = 0x48u;
-pub static tag_item_dtor: uint = 0x49u;
 pub static tag_item_trait_method_self_ty: uint = 0x4b;
 pub static tag_item_trait_method_self_ty_region: uint = 0x4c;
 

src/librustc/metadata/csearch.rs

@@ -230,13 +230,6 @@ pub fn get_impl_method(cstore: @mut cstore::CStore,
     decoder::get_impl_method(cstore.intr, cdata, def.node, mname)
 }
 
-/* If def names a class with a dtor, return it. Otherwise, return none. */
-pub fn struct_dtor(cstore: @mut cstore::CStore, def: ast::def_id)
-    -> Option<ast::def_id> {
-    let cdata = cstore::get_crate_data(cstore, def.crate);
-    decoder::struct_dtor(cdata, def.node)
-}
-
 pub fn get_item_visibility(cstore: @mut cstore::CStore,
                            def_id: ast::def_id)
                         -> ast::visibility {

src/librustc/metadata/decoder.rs

@@ -445,22 +445,6 @@ pub fn get_impl_method(intr: @ident_interner, cdata: cmd, id: ast::node_id,
     found.get()
 }
 
-pub fn struct_dtor(cdata: cmd, id: ast::node_id) -> Option<ast::def_id> {
-    let items = reader::get_doc(reader::Doc(cdata.data), tag_items);
-    let mut found = None;
-    let cls_items = match maybe_find_item(id, items) {
-            Some(it) => it,
-            None     => fail!(fmt!("struct_dtor: class id not found \
-              when looking up dtor for %d", id))
-    };
-    for reader::tagged_docs(cls_items, tag_item_dtor) |doc| {
-         let doc1 = reader::get_doc(doc, tag_def_id);
-         let did = reader::with_doc_data(doc1, |d| parse_def_id(d));
-         found = Some(translate_def_id(cdata, did));
-    };
-    found
-}
-
 pub fn get_symbol(data: @~[u8], id: ast::node_id) -> ~str {
     return item_symbol(lookup_item(id, data));
 }

src/librustc/metadata/encoder.rs

@@ -765,26 +765,6 @@ fn encode_info_for_item(ecx: @EncodeContext, ebml_w: &writer::Encoder,
            class itself */
         let idx = encode_info_for_struct(ecx, ebml_w, path,
                                          struct_def.fields, index);
-        /* Encode the dtor */
-        for struct_def.dtor.each |dtor| {
-            index.push(entry {val: dtor.node.id, pos: ebml_w.writer.tell()});
-          encode_info_for_ctor(ecx,
-                               ebml_w,
-                               dtor.node.id,
-                               ecx.tcx.sess.ident_of(
-                                   *ecx.tcx.sess.str_of(item.ident) +
-                                   ~"_dtor"),
-                               path,
-                               if generics.ty_params.len() > 0u {
-                                   Some(ii_dtor(copy *dtor,
-                                                item.ident,
-                                                copy *generics,
-                                                local_def(item.id))) }
-                               else {
-                                   None
-                               },
-                               generics);
-        }
 
         /* Index the class*/
         add_to_index();
@@ -816,13 +796,6 @@ fn encode_info_for_item(ecx: @EncodeContext, ebml_w: &writer::Encoder,
         encode_name(ecx, ebml_w, item.ident);
         encode_path(ecx, ebml_w, path, ast_map::path_name(item.ident));
         encode_region_param(ecx, ebml_w, item);
-        /* Encode the dtor */
-        /* Encode id for dtor */
-        for struct_def.dtor.each |dtor| {
-            do ebml_w.wr_tag(tag_item_dtor) {
-                encode_def_id(ebml_w, local_def(dtor.node.id));
-            }
-        };
 
         /* Encode def_ids for each field and method
          for methods, write all the stuff get_trait_method

src/librustc/middle/astencode.rs

@@ -327,15 +327,6 @@ fn simplify_ast(ii: &ast::inlined_item) -> ast::inlined_item {
       ast::ii_foreign(i) => {
         ast::ii_foreign(fld.fold_foreign_item(i))
       }
-      ast::ii_dtor(ref dtor, nm, ref tps, parent_id) => {
-        let dtor_body = fld.fold_block(&dtor.node.body);
-        ast::ii_dtor(
-            codemap::spanned {
-                node: ast::struct_dtor_ { body: dtor_body,
-                                          .. /*bad*/copy (*dtor).node },
-                .. (/*bad*/copy *dtor) },
-            nm, /*bad*/copy *tps, parent_id)
-      }
     }
 }
 
@@ -363,23 +354,6 @@ fn renumber_ast(xcx: @ExtendedDecodeContext, ii: ast::inlined_item)
       ast::ii_foreign(i) => {
         ast::ii_foreign(fld.fold_foreign_item(i))
       }
-      ast::ii_dtor(ref dtor, nm, ref generics, parent_id) => {
-        let dtor_body = fld.fold_block(&dtor.node.body);
-        let dtor_attrs = fld.fold_attributes(/*bad*/copy (*dtor).node.attrs);
-        let new_generics = fold::fold_generics(generics, fld);
-        let dtor_id = fld.new_id((*dtor).node.id);
-        let new_parent = xcx.tr_def_id(parent_id);
-        let new_self = fld.new_id((*dtor).node.self_id);
-        ast::ii_dtor(
-            codemap::spanned {
-                node: ast::struct_dtor_ { id: dtor_id,
-                                          attrs: dtor_attrs,
-                                          self_id: new_self,
-                                          body: dtor_body },
-                .. (/*bad*/copy *dtor)
-            },
-            nm, new_generics, new_parent)
-      }
      }
 }
 

src/librustc/middle/borrowck/check_loans.rs

@@ -629,8 +629,7 @@ fn check_loans_in_fn(fk: &visit::fn_kind,
 
     let declared_purity, src;
     match *fk {
-        visit::fk_item_fn(*) | visit::fk_method(*) |
-        visit::fk_dtor(*) => {
+        visit::fk_item_fn(*) | visit::fk_method(*) => {
             declared_purity = ty::ty_fn_purity(fty);
             src = id;
         }
@@ -658,8 +657,7 @@ fn check_loans_in_fn(fk: &visit::fn_kind,
                     // inherits the fn_args from enclosing ctxt
                 }
                 visit::fk_anon(*) | visit::fk_fn_block(*) |
-                visit::fk_method(*) | visit::fk_item_fn(*) |
-                visit::fk_dtor(*) => {
+                visit::fk_method(*) | visit::fk_item_fn(*) => {
                     let mut fn_args = ~[];
                     for decl.inputs.each |input| {
                         // For the purposes of purity, only consider function-

src/librustc/middle/borrowck/gather_loans.rs

@@ -104,8 +104,7 @@ fn req_loans_in_fn(fk: &visit::fn_kind,
 
     match *fk {
         visit::fk_anon(*) | visit::fk_fn_block(*) => {}
-        visit::fk_item_fn(*) | visit::fk_method(*) |
-        visit::fk_dtor(*) => {
+        visit::fk_item_fn(*) | visit::fk_method(*) => {
             self.item_ub = body.node.id;
         }
     }

src/librustc/middle/kind.rs

@@ -153,17 +153,6 @@ fn check_item(item: @item, cx: Context, visitor: visit::vt<Context>) {
                     }
                 }
             }
-            item_struct(struct_def, _) => {
-                match struct_def.dtor {
-                    None => {}
-                    Some(ref dtor) => {
-                        let struct_did = def_id { crate: 0, node: item.id };
-                        check_struct_safe_for_destructor(cx,
-                                                         dtor.span,
-                                                         struct_did);
-                    }
-                }
-            }
             _ => {}
         }
     }

src/librustc/middle/lint.rs

@@ -57,7 +57,6 @@ pub enum lint {
     type_limits,
     default_methods,
     deprecated_mutable_fields,
-    deprecated_drop,
     unused_unsafe,
 
     managed_heap_memory,
@@ -210,13 +209,6 @@ pub fn get_lint_dict() -> LintDict {
             default: deny
         }),
 
-        (~"deprecated_drop",
-         LintSpec {
-            lint: deprecated_drop,
-            desc: "deprecated \"drop\" notation for the destructor",
-            default: deny
-        }),
-
         (~"unused_unsafe",
          LintSpec {
             lint: unused_unsafe,
@@ -463,7 +455,6 @@ fn check_item(i: @ast::item, cx: ty::ctxt) {
     check_item_type_limits(cx, i);
     check_item_default_methods(cx, i);
     check_item_deprecated_mutable_fields(cx, i);
-    check_item_deprecated_drop(cx, i);
     check_item_unused_unsafe(cx, i);
     check_item_unused_mut(cx, i);
 }
@@ -668,26 +659,6 @@ fn check_item_deprecated_mutable_fields(cx: ty::ctxt, item: @ast::item) {
     }
 }
 
-fn check_item_deprecated_drop(cx: ty::ctxt, item: @ast::item) {
-    match item.node {
-        ast::item_struct(struct_def, _) => {
-            match struct_def.dtor {
-                None => {}
-                Some(ref dtor) => {
-                    cx.sess.span_lint(deprecated_drop,
-                                      item.id,
-                                      item.id,
-                                      dtor.span,
-                                      ~"`drop` notation for destructors is \
-                                        deprecated; implement the `Drop` \
-                                        trait instead");
-                }
-            }
-        }
-        _ => {}
-    }
-}
-
 fn check_item_ctypes(cx: ty::ctxt, it: @ast::item) {
 
     fn check_foreign_fn(cx: ty::ctxt, fn_id: ast::node_id,

src/librustc/middle/liveness.rs

@@ -117,7 +117,7 @@ use syntax::ast::*;
 use syntax::codemap::span;
 use syntax::parse::token::special_idents;
 use syntax::print::pprust::{expr_to_str, block_to_str};
-use syntax::visit::{fk_anon, fk_dtor, fk_fn_block, fk_item_fn, fk_method};
+use syntax::visit::{fk_anon, fk_fn_block, fk_item_fn, fk_method};
 use syntax::visit::{vt};
 use syntax::{visit, ast_util};
 
@@ -440,9 +440,6 @@ fn visit_fn(fk: &visit::fn_kind,
                 sty_static => {}
             }
         }
-        fk_dtor(_, _, self_id, _) => {
-            fn_maps.add_variable(Arg(self_id, special_idents::self_));
-        }
         fk_item_fn(*) | fk_anon(*) | fk_fn_block(*) => {}
     }
 

src/librustc/middle/region.rs

@@ -438,8 +438,7 @@ pub fn resolve_fn(fk: &visit::fn_kind,
                   cx: ctxt,
                   visitor: visit::vt<ctxt>) {
     let fn_cx = match *fk {
-        visit::fk_item_fn(*) | visit::fk_method(*) |
-        visit::fk_dtor(*) => {
+        visit::fk_item_fn(*) | visit::fk_method(*) => {
             // Top-level functions are a root scope.
             ctxt {parent: Some(id),.. cx}
         }

src/librustc/middle/resolve.rs

@@ -47,7 +47,7 @@ use syntax::ast::{named_field, ne, neg, node_id, pat, pat_enum, pat_ident};
 use syntax::ast::{Path, pat_lit, pat_range, pat_struct};
 use syntax::ast::{prim_ty, private, provided};
 use syntax::ast::{public, required, rem, self_ty_, shl, shr, stmt_decl};
-use syntax::ast::{struct_dtor, struct_field, struct_variant_kind};
+use syntax::ast::{struct_field, struct_variant_kind};
 use syntax::ast::{sty_static, subtract, trait_ref, tuple_variant_kind, Ty};
 use syntax::ast::{ty_bool, ty_char, ty_f, ty_f32, ty_f64, ty_float, ty_i};
 use syntax::ast::{ty_i16, ty_i32, ty_i64, ty_i8, ty_int, TyParam, ty_path};
@@ -3512,7 +3512,6 @@ pub impl Resolver {
                 self.resolve_struct(item.id,
                                     generics,
                                     struct_def.fields,
-                                    &struct_def.dtor,
                                     visitor);
             }
 
@@ -3770,7 +3769,6 @@ pub impl Resolver {
                       id: node_id,
                       generics: &Generics,
                       fields: &[@struct_field],
-                      optional_destructor: &Option<struct_dtor>,
                       visitor: ResolveVisitor) {
         // If applicable, create a rib for the type parameters.
         do self.with_type_parameter_rib(HasTypeParameters
@@ -3784,23 +3782,6 @@ pub impl Resolver {
             for fields.each |field| {
                 self.resolve_type(field.node.ty, visitor);
             }
-
-            // Resolve the destructor, if applicable.
-            match *optional_destructor {
-                None => {
-                    // Nothing to do.
-                }
-                Some(ref destructor) => {
-                    self.resolve_function(NormalRibKind,
-                                          None,
-                                          NoTypeParameters,
-                                          &destructor.node.body,
-                                          HasSelfBinding
-                                            ((*destructor).node.self_id,
-                                             true),
-                                          visitor);
-                }
-            }
         }
     }