Auto merge of #46657 - nikomatsakis:resolve-lifetimes-query, r=arielb1

move `resolve_lifetimes` into a proper query

Now that we made `resolve_lifetimes` into a query, elision errors no
longer abort compilation, which affects some tests.

Also, remove `dep_graph_crosscontaminate_tables` -- there is no a path in
the dep-graph, though red-green handles it. The same scenario
is (correctly) tested by issue-42602.rs in any case.

r? @michaelwoerister

src/librustc/dep_graph/dep_node.rs

@@ -588,9 +588,10 @@ define_dep_nodes!( <'tcx>
     [] NativeLibraryKind(DefId),
     [input] LinkArgs,
 
-    [input] NamedRegion(DefIndex),
-    [input] IsLateBound(DefIndex),
-    [input] ObjectLifetimeDefaults(DefIndex),
+    [] ResolveLifetimes(CrateNum),
+    [] NamedRegion(DefIndex),
+    [] IsLateBound(DefIndex),
+    [] ObjectLifetimeDefaults(DefIndex),
 
     [] Visibility(DefId),
     [] DepKind(CrateNum),

src/librustc/hir/mod.rs

@@ -28,7 +28,7 @@ pub use self::UnsafeSource::*;
 pub use self::Visibility::{Public, Inherited};
 
 use hir::def::Def;
-use hir::def_id::{DefId, DefIndex, CRATE_DEF_INDEX};
+use hir::def_id::{DefId, DefIndex, LocalDefId, CRATE_DEF_INDEX};
 use util::nodemap::{NodeMap, FxHashSet};
 
 use syntax_pos::{Span, DUMMY_SP};
@@ -92,6 +92,16 @@ pub struct HirId {
     pub local_id: ItemLocalId,
 }
 
+impl HirId {
+    pub fn owner_def_id(self) -> DefId {
+        DefId::local(self.owner)
+    }
+
+    pub fn owner_local_def_id(self) -> LocalDefId {
+        LocalDefId::from_def_id(DefId::local(self.owner))
+    }
+}
+
 impl serialize::UseSpecializedEncodable for HirId {
     fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
         let HirId {

src/librustc/ty/context.rs

@@ -802,8 +802,6 @@ pub struct GlobalCtxt<'tcx> {
     /// Export map produced by name resolution.
     export_map: FxHashMap<DefId, Rc<Vec<Export>>>,
 
-    named_region_map: NamedRegionMap,
-
     pub hir: hir_map::Map<'tcx>,
 
     /// A map from DefPathHash -> DefId. Includes DefIds from the local crate
@@ -986,7 +984,6 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
                                   arenas: &'tcx GlobalArenas<'tcx>,
                                   arena: &'tcx DroplessArena,
                                   resolutions: ty::Resolutions,
-                                  named_region_map: resolve_lifetime::NamedRegionMap,
                                   hir: hir_map::Map<'tcx>,
                                   on_disk_query_result_cache: maps::OnDiskCache<'tcx>,
                                   crate_name: &str,
@@ -1044,27 +1041,6 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
                             .insert(hir_id.local_id,
                                     Rc::new(StableVec::new(v)));
         }
-        let mut defs = FxHashMap();
-        for (k, v) in named_region_map.defs {
-            let hir_id = hir.node_to_hir_id(k);
-            let map = defs.entry(hir_id.owner)
-                .or_insert_with(|| Rc::new(FxHashMap()));
-            Rc::get_mut(map).unwrap().insert(hir_id.local_id, v);
-        }
-        let mut late_bound = FxHashMap();
-        for k in named_region_map.late_bound {
-            let hir_id = hir.node_to_hir_id(k);
-            let map = late_bound.entry(hir_id.owner)
-                .or_insert_with(|| Rc::new(FxHashSet()));
-            Rc::get_mut(map).unwrap().insert(hir_id.local_id);
-        }
-        let mut object_lifetime_defaults = FxHashMap();
-        for (k, v) in named_region_map.object_lifetime_defaults {
-            let hir_id = hir.node_to_hir_id(k);
-            let map = object_lifetime_defaults.entry(hir_id.owner)
-                .or_insert_with(|| Rc::new(FxHashMap()));
-            Rc::get_mut(map).unwrap().insert(hir_id.local_id, Rc::new(v));
-        }
 
         tls::enter_global(GlobalCtxt {
             sess: s,
@@ -1074,11 +1050,6 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             dep_graph: dep_graph.clone(),
             on_disk_query_result_cache,
             types: common_types,
-            named_region_map: NamedRegionMap {
-                defs,
-                late_bound,
-                object_lifetime_defaults,
-            },
             trait_map,
             export_map: resolutions.export_map.into_iter().map(|(k, v)| {
                 (k, Rc::new(v))
@@ -2176,27 +2147,12 @@ impl<T, R, E> InternIteratorElement<T, R> for Result<T, E> {
     }
 }
 
-struct NamedRegionMap {
-    defs: FxHashMap<DefIndex, Rc<FxHashMap<ItemLocalId, resolve_lifetime::Region>>>,
-    late_bound: FxHashMap<DefIndex, Rc<FxHashSet<ItemLocalId>>>,
-    object_lifetime_defaults:
-        FxHashMap<
-            DefIndex,
-            Rc<FxHashMap<ItemLocalId, Rc<Vec<ObjectLifetimeDefault>>>>,
-        >,
-}
-
 pub fn provide(providers: &mut ty::maps::Providers) {
     // FIXME(#44234) - almost all of these queries have no sub-queries and
     // therefore no actual inputs, they're just reading tables calculated in
     // resolve! Does this work? Unsure! That's what the issue is about
     providers.in_scope_traits_map = |tcx, id| tcx.gcx.trait_map.get(&id).cloned();
     providers.module_exports = |tcx, id| tcx.gcx.export_map.get(&id).cloned();
-    providers.named_region_map = |tcx, id| tcx.gcx.named_region_map.defs.get(&id).cloned();
-    providers.is_late_bound_map = |tcx, id| tcx.gcx.named_region_map.late_bound.get(&id).cloned();
-    providers.object_lifetime_defaults_map = |tcx, id| {
-        tcx.gcx.named_region_map.object_lifetime_defaults.get(&id).cloned()
-    };
     providers.crate_name = |tcx, id| {
         assert_eq!(id, LOCAL_CRATE);
         tcx.crate_name

src/librustc/ty/maps/config.rs

@@ -443,6 +443,12 @@ impl<'tcx> QueryDescription<'tcx> for queries::link_args<'tcx> {
     }
 }
 
+impl<'tcx> QueryDescription<'tcx> for queries::resolve_lifetimes<'tcx> {
+    fn describe(_tcx: TyCtxt, _: CrateNum) -> String {
+        format!("resolving lifetimes")
+    }
+}
+
 impl<'tcx> QueryDescription<'tcx> for queries::named_region_map<'tcx> {
     fn describe(_tcx: TyCtxt, _: DefIndex) -> String {
         format!("looking up a named region")

src/librustc/ty/maps/mod.rs

@@ -23,7 +23,7 @@ use middle::cstore::{NativeLibraryKind, DepKind, CrateSource, ExternConstBody};
 use middle::privacy::AccessLevels;
 use middle::reachable::ReachableSet;
 use middle::region;
-use middle::resolve_lifetime::{Region, ObjectLifetimeDefault};
+use middle::resolve_lifetime::{ResolveLifetimes, Region, ObjectLifetimeDefault};
 use middle::stability::{self, DeprecationEntry};
 use middle::lang_items::{LanguageItems, LangItem};
 use middle::exported_symbols::SymbolExportLevel;
@@ -306,6 +306,8 @@ define_maps! { <'tcx>
         -> Option<NativeLibraryKind>,
     [] fn link_args: link_args_node(CrateNum) -> Rc<Vec<String>>,
 
+    // Lifetime resolution. See `middle::resolve_lifetimes`.
+    [] fn resolve_lifetimes: ResolveLifetimes(CrateNum) -> Rc<ResolveLifetimes>,
     [] fn named_region_map: NamedRegion(DefIndex) ->
         Option<Rc<FxHashMap<ItemLocalId, Region>>>,
     [] fn is_late_bound_map: IsLateBound(DefIndex) ->

src/librustc/ty/maps/plumbing.rs

@@ -875,6 +875,7 @@ pub fn force_from_dep_node<'a, 'gcx, 'lcx>(tcx: TyCtxt<'a, 'gcx, 'lcx>,
         DepKind::NativeLibraryKind => { force!(native_library_kind, def_id!()); }
         DepKind::LinkArgs => { force!(link_args, LOCAL_CRATE); }
 
+        DepKind::ResolveLifetimes => { force!(resolve_lifetimes, krate!()); }
         DepKind::NamedRegion => { force!(named_region_map, def_id!().index); }
         DepKind::IsLateBound => { force!(is_late_bound_map, def_id!().index); }
         DepKind::ObjectLifetimeDefaults => {

src/librustc_driver/driver.rs

@@ -19,7 +19,7 @@ use rustc::session::CompileIncomplete;
 use rustc::session::config::{self, Input, OutputFilenames, OutputType};
 use rustc::session::search_paths::PathKind;
 use rustc::lint;
-use rustc::middle::{self, stability, reachable};
+use rustc::middle::{self, stability, reachable, resolve_lifetime};
 use rustc::middle::cstore::CrateStore;
 use rustc::middle::privacy::AccessLevels;
 use rustc::ty::{self, TyCtxt, Resolutions, GlobalArenas};
@@ -928,6 +928,7 @@ pub fn default_provide(providers: &mut ty::maps::Providers) {
     borrowck::provide(providers);
     mir::provide(providers);
     reachable::provide(providers);
+    resolve_lifetime::provide(providers);
     rustc_privacy::provide(providers);
     DefaultTransCrate::provide(providers);
     typeck::provide(providers);
@@ -984,10 +985,6 @@ pub fn phase_3_run_analysis_passes<'tcx, F, R>(control: &CompileController,
         "load query result cache",
         || rustc_incremental::load_query_result_cache(sess));
 
-    let named_region_map = time(time_passes,
-                                "lifetime resolution",
-                                || middle::resolve_lifetime::krate(sess, cstore, &hir_map))?;
-
     time(time_passes,
          "looking for entry point",
          || middle::entry::find_entry_point(sess, &hir_map));
@@ -1022,7 +1019,6 @@ pub fn phase_3_run_analysis_passes<'tcx, F, R>(control: &CompileController,
                              arenas,
                              arena,
                              resolutions,
-                             named_region_map,
                              hir_map,
                              query_result_on_disk_cache,
                              name,

src/librustc_driver/test.rs

@@ -18,7 +18,6 @@ use rustc_lint;
 use rustc_resolve::MakeGlobMap;
 use rustc_trans;
 use rustc::middle::region;
-use rustc::middle::resolve_lifetime;
 use rustc::ty::subst::{Kind, Subst};
 use rustc::traits::{ObligationCause, Reveal};
 use rustc::ty::{self, Ty, TyCtxt, TypeFoldable};
@@ -137,7 +136,6 @@ fn test_env<F>(source_string: &str,
     let hir_map = hir_map::map_crate(&sess, &*cstore, &mut hir_forest, &defs);
 
     // run just enough stuff to build a tcx:
-    let named_region_map = resolve_lifetime::krate(&sess, &*cstore, &hir_map);
     let (tx, _rx) = mpsc::channel();
     let outputs = OutputFilenames {
         out_directory: PathBuf::new(),
@@ -153,7 +151,6 @@ fn test_env<F>(source_string: &str,
                              &arenas,
                              &arena,
                              resolutions,
-                             named_region_map.unwrap(),
                              hir_map,
                              OnDiskCache::new_empty(sess.codemap()),
                              "test_crate",

src/librustc_typeck/astconv.rs

@@ -140,7 +140,18 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
             }
 
             None => {
-                self.re_infer(lifetime.span, def).expect("unelided lifetime in signature")
+                self.re_infer(lifetime.span, def)
+                    .unwrap_or_else(|| {
+                        // This indicates an illegal lifetime
+                        // elision. `resolve_lifetime` should have
+                        // reported an error in this case -- but if
+                        // not, let's error out.
+                        tcx.sess.delay_span_bug(lifetime.span, "unelided lifetime in signature");
+
+                        // Supply some dummy value. We don't have an
+                        // `re_error`, annoyingly, so use `'static`.
+                        tcx.types.re_static
+                    })
             }
         };
 

src/test/compile-fail/dep_graph_crosscontaminate_tables.rs

@@ -1,40 +0,0 @@
-// Copyright 2016 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 the `TypeckTables` nodes for impl items are independent from
-// one another.
-
-// compile-flags: -Z query-dep-graph
-
-#![feature(rustc_attrs)]
-
-struct Foo {
-    x: u8
-}
-
-impl Foo {
-    // Changing the item `new`...
-    #[rustc_if_this_changed(HirBody)]
-    fn new() -> Foo {
-        Foo { x: 0 }
-    }
-
-    // ...should not cause us to recompute the tables for `with`!
-    #[rustc_then_this_would_need(TypeckTables)] //~ ERROR no path
-    fn with(x: u8) -> Foo {
-        Foo { x: x }
-    }
-}
-
-fn main() {
-    let f = Foo::new();
-    let g = Foo::with(22);
-    assert_eq!(f.x, g.x - 22);
-}

src/test/compile-fail/where-lifetime-resolution.rs

@@ -8,8 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-trait Trait1 {}
-trait Trait2 {}
+trait Trait1<'a> {}
+trait Trait2<'a, 'b> {}
 
 fn f() where
     for<'a> Trait1<'a>: Trait1<'a>, // OK

src/test/incremental/issue-42602.rs

@@ -16,8 +16,9 @@
 // This was fixed by improving the resolution of the `FnOnce` trait
 // selection node.
 
-// revisions:cfail1
+// revisions:cfail1 cfail2 cfail3
 // compile-flags:-Zquery-dep-graph
+// must-compile-successfully
 
 #![feature(rustc_attrs)]
 
@@ -27,16 +28,24 @@ fn main() {
 }
 
 mod a {
-    #[rustc_if_this_changed(HirBody)]
+    #[cfg(cfail1)]
     pub fn foo() {
         let x = vec![1, 2, 3];
         let v = || ::std::mem::drop(x);
         v();
     }
+
+    #[cfg(not(cfail1))]
+    pub fn foo() {
+        let x = vec![1, 2, 3, 4];
+        let v = || ::std::mem::drop(x);
+        v();
+    }
 }
 
 mod b {
-    #[rustc_then_this_would_need(TypeckTables)] //[cfail1]~ ERROR no path
+    #[rustc_clean(cfg="cfail2")]
+    #[rustc_clean(cfg="cfail3")]
     pub fn bar() {
         let x = vec![1, 2, 3];
         let v = || ::std::mem::drop(x);

src/test/ui/rfc1598-generic-associated-types/construct_with_other_type.rs

@@ -23,6 +23,7 @@ trait Baz {
 impl<T> Baz for T where T: Foo {
     type Quux<'a> = <T as Foo>::Bar<'a, 'static>;
     //~^ ERROR undeclared lifetime
+    //~| ERROR lifetime parameters are not allowed on this type [E0110]
 }
 
 fn main() {}

src/test/ui/rfc1598-generic-associated-types/construct_with_other_type.stderr

@@ -4,5 +4,11 @@ error[E0261]: use of undeclared lifetime name `'a`
 24 |     type Quux<'a> = <T as Foo>::Bar<'a, 'static>;
    |                                     ^^ undeclared lifetime
 
-error: aborting due to previous error
+error[E0110]: lifetime parameters are not allowed on this type
+  --> $DIR/construct_with_other_type.rs:24:37
+   |
+24 |     type Quux<'a> = <T as Foo>::Bar<'a, 'static>;
+   |                                     ^^ lifetime parameter not allowed on this type
+
+error: aborting due to 2 previous errors
 

src/test/ui/rfc1598-generic-associated-types/generic-associated-types-where.stderr

@@ -4,5 +4,5 @@ error[E0261]: use of undeclared lifetime name `'a`
 34 |     type WithDefault<'a, T> = &'a Iterator<T>;
    |                                ^^ undeclared lifetime
 
-error: aborting due to previous error
+error: cannot continue compilation due to previous error
 

src/test/ui/rfc1598-generic-associated-types/iterable.rs

@@ -16,8 +16,10 @@ trait Iterable {
     type Item<'a>;
     type Iter<'a>: Iterator<Item = Self::Item<'a>>;
     //~^ ERROR undeclared lifetime
+    //~| ERROR lifetime parameters are not allowed on this type [E0110]
 
     fn iter<'a>(&'a self) -> Self::Iter<'a>;
+    //~^ ERROR lifetime parameters are not allowed on this type [E0110]
 }
 
 fn main() {}

src/test/ui/rfc1598-generic-associated-types/iterable.stderr

@@ -4,5 +4,17 @@ error[E0261]: use of undeclared lifetime name `'a`
 17 |     type Iter<'a>: Iterator<Item = Self::Item<'a>>;
    |                                               ^^ undeclared lifetime
 
-error: aborting due to previous error
+error[E0110]: lifetime parameters are not allowed on this type
+  --> $DIR/iterable.rs:17:47
+   |
+17 |     type Iter<'a>: Iterator<Item = Self::Item<'a>>;
+   |                                               ^^ lifetime parameter not allowed on this type
+
+error[E0110]: lifetime parameters are not allowed on this type
+  --> $DIR/iterable.rs:21:41
+   |
+21 |     fn iter<'a>(&'a self) -> Self::Iter<'a>;
+   |                                         ^^ lifetime parameter not allowed on this type
+
+error: aborting due to 3 previous errors