Auto merge of #44766 - sunjay:lift_generics, r=nikomatsakis

Move Generics from MethodSig to TraitItem and ImplItem

As part of `rust-impl-period/WG-compiler-traits`, we want to "lift" `Generics` from `MethodSig` into `TraitItem` and `ImplItem`. This is in preparation for adding associated type generics. (https://github.com/rust-lang/rust/issues/44265#issuecomment-331172238)

Currently this change is only made in the AST. In the future, it may also impact the HIR. (Still discussing)

To understand this PR, it's probably best to start from the changes to `ast.rs` and then work your way to the other files to understand the far reaching effects of this change.

r? @nikomatsakis

23 files changed, 107 insertions, 125 deletions

diff --git a/src/librustc/hir/intravisit.rs b/src/librustc/hir/intravisit.rs
index 1755b3bca05..d99d7cd897b 100644
--- a/src/librustc/hir/intravisit.rs
+++ b/src/librustc/hir/intravisit.rs
@@ -780,9 +780,7 @@ pub fn walk_fn_kind<'v, V: Visitor<'v>>(visitor: &mut V, function_kind: FnKind<'
         FnKind::ItemFn(_, generics, ..) => {
             visitor.visit_generics(generics);
         }
-        FnKind::Method(_, sig, ..) => {
-            visitor.visit_generics(&sig.generics);
-        }
+        FnKind::Method(..) |
         FnKind::Closure(_) => {}
     }
 }
@@ -802,6 +800,7 @@ pub fn walk_fn<'v, V: Visitor<'v>>(visitor: &mut V,
 pub fn walk_trait_item<'v, V: Visitor<'v>>(visitor: &mut V, trait_item: &'v TraitItem) {
     visitor.visit_name(trait_item.span, trait_item.name);
     walk_list!(visitor, visit_attribute, &trait_item.attrs);
+    visitor.visit_generics(&trait_item.generics);
     match trait_item.node {
         TraitItemKind::Const(ref ty, default) => {
             visitor.visit_id(trait_item.id);
@@ -810,7 +809,6 @@ pub fn walk_trait_item<'v, V: Visitor<'v>>(visitor: &mut V, trait_item: &'v Trai
         }
         TraitItemKind::Method(ref sig, TraitMethod::Required(ref names)) => {
             visitor.visit_id(trait_item.id);
-            visitor.visit_generics(&sig.generics);
             visitor.visit_fn_decl(&sig.decl);
             for name in names {
                 visitor.visit_name(name.span, name.node);
@@ -852,6 +850,7 @@ pub fn walk_impl_item<'v, V: Visitor<'v>>(visitor: &mut V, impl_item: &'v ImplIt
         ref vis,
         ref defaultness,
         ref attrs,
+        ref generics,
         ref node,
         span
     } = *impl_item;
@@ -860,6 +859,7 @@ pub fn walk_impl_item<'v, V: Visitor<'v>>(visitor: &mut V, impl_item: &'v ImplIt
     visitor.visit_vis(vis);
     visitor.visit_defaultness(defaultness);
     walk_list!(visitor, visit_attribute, attrs);
+    visitor.visit_generics(generics);
     match *node {
         ImplItemKind::Const(ref ty, body) => {
             visitor.visit_id(impl_item.id);
diff --git a/src/librustc/hir/lowering.rs b/src/librustc/hir/lowering.rs
index 848da9637a2..0a9b44784b4 100644
--- a/src/librustc/hir/lowering.rs
+++ b/src/librustc/hir/lowering.rs
@@ -1539,6 +1539,7 @@ impl<'a> LoweringContext<'a> {
                 hir_id,
                 name: this.lower_ident(i.ident),
                 attrs: this.lower_attrs(&i.attrs),
+                generics: this.lower_generics(&i.generics),
                 node: match i.node {
                     TraitItemKind::Const(ref ty, ref default) => {
                         hir::TraitItemKind::Const(this.lower_ty(ty),
@@ -1603,6 +1604,7 @@ impl<'a> LoweringContext<'a> {
                 hir_id,
                 name: this.lower_ident(i.ident),
                 attrs: this.lower_attrs(&i.attrs),
+                generics: this.lower_generics(&i.generics),
                 vis: this.lower_visibility(&i.vis, None),
                 defaultness: this.lower_defaultness(i.defaultness, true /* [1] */),
                 node: match i.node {
@@ -1729,7 +1731,6 @@ impl<'a> LoweringContext<'a> {
 
     fn lower_method_sig(&mut self, sig: &MethodSig) -> hir::MethodSig {
         hir::MethodSig {
-            generics: self.lower_generics(&sig.generics),
             abi: sig.abi,
             unsafety: self.lower_unsafety(sig.unsafety),
             constness: self.lower_constness(sig.constness),
diff --git a/src/librustc/hir/mod.rs b/src/librustc/hir/mod.rs
index 5ad0ff04c1b..fb3fc8a2da4 100644
--- a/src/librustc/hir/mod.rs
+++ b/src/librustc/hir/mod.rs
@@ -1295,7 +1295,6 @@ pub struct MethodSig {
     pub constness: Constness,
     pub abi: Abi,
     pub decl: P<FnDecl>,
-    pub generics: Generics,
 }
 
 // The bodies for items are stored "out of line", in a separate
@@ -1316,6 +1315,7 @@ pub struct TraitItem {
     pub name: Name,
     pub hir_id: HirId,
     pub attrs: HirVec<Attribute>,
+    pub generics: Generics,
     pub node: TraitItemKind,
     pub span: Span,
 }
@@ -1360,6 +1360,7 @@ pub struct ImplItem {
     pub vis: Visibility,
     pub defaultness: Defaultness,
     pub attrs: HirVec<Attribute>,
+    pub generics: Generics,
     pub node: ImplItemKind,
     pub span: Span,
 }
diff --git a/src/librustc/hir/print.rs b/src/librustc/hir/print.rs
index 7287e599b29..b4614873550 100644
--- a/src/librustc/hir/print.rs
+++ b/src/librustc/hir/print.rs
@@ -880,6 +880,7 @@ impl<'a> State<'a> {
     pub fn print_method_sig(&mut self,
                             name: ast::Name,
                             m: &hir::MethodSig,
+                            generics: &hir::Generics,
                             vis: &hir::Visibility,
                             arg_names: &[Spanned<ast::Name>],
                             body_id: Option<hir::BodyId>)
@@ -889,7 +890,7 @@ impl<'a> State<'a> {
                       m.constness,
                       m.abi,
                       Some(name),
-                      &m.generics,
+                      generics,
                       vis,
                       arg_names,
                       body_id)
@@ -905,12 +906,14 @@ impl<'a> State<'a> {
                 self.print_associated_const(ti.name, &ty, default, &hir::Inherited)?;
             }
             hir::TraitItemKind::Method(ref sig, hir::TraitMethod::Required(ref arg_names)) => {
-                self.print_method_sig(ti.name, sig, &hir::Inherited, arg_names, None)?;
+                self.print_method_sig(ti.name, sig, &ti.generics, &hir::Inherited, arg_names,
+                    None)?;
                 self.s.word(";")?;
             }
             hir::TraitItemKind::Method(ref sig, hir::TraitMethod::Provided(body)) => {
                 self.head("")?;
-                self.print_method_sig(ti.name, sig, &hir::Inherited, &[], Some(body))?;
+                self.print_method_sig(ti.name, sig, &ti.generics, &hir::Inherited, &[],
+                    Some(body))?;
                 self.nbsp()?;
                 self.end()?; // need to close a box
                 self.end()?; // need to close a box
@@ -938,7 +941,7 @@ impl<'a> State<'a> {
             }
             hir::ImplItemKind::Method(ref sig, body) => {
                 self.head("")?;
-                self.print_method_sig(ii.name, sig, &ii.vis, &[], Some(body))?;
+                self.print_method_sig(ii.name, sig, &ii.generics, &ii.vis, &[], Some(body))?;
                 self.nbsp()?;
                 self.end()?; // need to close a box
                 self.end()?; // need to close a box
diff --git a/src/librustc/ich/impls_hir.rs b/src/librustc/ich/impls_hir.rs
index c0fae8bf8bd..994f0bd16b1 100644
--- a/src/librustc/ich/impls_hir.rs
+++ b/src/librustc/ich/impls_hir.rs
@@ -232,8 +232,7 @@ impl_stable_hash_for!(struct hir::MethodSig {
     unsafety,
     constness,
     abi,
-    decl,
-    generics
+    decl
 });
 
 impl_stable_hash_for!(struct hir::TypeBinding {
@@ -709,6 +708,7 @@ impl<'gcx> HashStable<StableHashingContext<'gcx>> for hir::TraitItem {
             hir_id: _,
             name,
             ref attrs,
+            ref generics,
             ref node,
             span
         } = *self;
@@ -716,6 +716,7 @@ impl<'gcx> HashStable<StableHashingContext<'gcx>> for hir::TraitItem {
         hcx.hash_hir_item_like(attrs, |hcx| {
             name.hash_stable(hcx, hasher);
             attrs.hash_stable(hcx, hasher);
+            generics.hash_stable(hcx, hasher);
             node.hash_stable(hcx, hasher);
             span.hash_stable(hcx, hasher);
         });
@@ -744,6 +745,7 @@ impl<'gcx> HashStable<StableHashingContext<'gcx>> for hir::ImplItem {
             ref vis,
             defaultness,
             ref attrs,
+            ref generics,
             ref node,
             span
         } = *self;
@@ -753,6 +755,7 @@ impl<'gcx> HashStable<StableHashingContext<'gcx>> for hir::ImplItem {
             vis.hash_stable(hcx, hasher);
             defaultness.hash_stable(hcx, hasher);
             attrs.hash_stable(hcx, hasher);
+            generics.hash_stable(hcx, hasher);
             node.hash_stable(hcx, hasher);
             span.hash_stable(hcx, hasher);
         });
diff --git a/src/librustc/middle/reachable.rs b/src/librustc/middle/reachable.rs
index bb6213cb5fa..2037bc01a5b 100644
--- a/src/librustc/middle/reachable.rs
+++ b/src/librustc/middle/reachable.rs
@@ -58,11 +58,10 @@ fn item_might_be_inlined(item: &hir::Item) -> bool {
 }
 
 fn method_might_be_inlined<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                                     sig: &hir::MethodSig,
                                      impl_item: &hir::ImplItem,
                                      impl_src: DefId) -> bool {
     if attr::requests_inline(&impl_item.attrs) ||
-        generics_require_inlining(&sig.generics) {
+        generics_require_inlining(&impl_item.generics) {
         return true
     }
     if let Some(impl_node_id) = tcx.hir.as_local_node_id(impl_src) {
@@ -176,8 +175,8 @@ impl<'a, 'tcx> ReachableContext<'a, 'tcx> {
             Some(hir_map::NodeImplItem(impl_item)) => {
                 match impl_item.node {
                     hir::ImplItemKind::Const(..) => true,
-                    hir::ImplItemKind::Method(ref sig, _) => {
-                        if generics_require_inlining(&sig.generics) ||
+                    hir::ImplItemKind::Method(..) => {
+                        if generics_require_inlining(&impl_item.generics) ||
                                 attr::requests_inline(&impl_item.attrs) {
                             true
                         } else {
@@ -293,9 +292,9 @@ impl<'a, 'tcx> ReachableContext<'a, 'tcx> {
                     hir::ImplItemKind::Const(_, body) => {
                         self.visit_nested_body(body);
                     }
-                    hir::ImplItemKind::Method(ref sig, body) => {
+                    hir::ImplItemKind::Method(_, body) => {
                         let did = self.tcx.hir.get_parent_did(search_item);
-                        if method_might_be_inlined(self.tcx, sig, impl_item, did) {
+                        if method_might_be_inlined(self.tcx, impl_item, did) {
                             self.visit_nested_body(body)
                         }
                     }
diff --git a/src/librustc/middle/resolve_lifetime.rs b/src/librustc/middle/resolve_lifetime.rs
index d0c5460fa97..dc912f1c1b6 100644
--- a/src/librustc/middle/resolve_lifetime.rs
+++ b/src/librustc/middle/resolve_lifetime.rs
@@ -412,7 +412,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
         if let hir::TraitItemKind::Method(ref sig, _) = trait_item.node {
             self.visit_early_late(
                 Some(self.hir_map.get_parent(trait_item.id)),
-                &sig.decl, &sig.generics,
+                &sig.decl, &trait_item.generics,
                 |this| intravisit::walk_trait_item(this, trait_item))
         } else {
             intravisit::walk_trait_item(self, trait_item);
@@ -423,7 +423,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
         if let hir::ImplItemKind::Method(ref sig, _) = impl_item.node {
             self.visit_early_late(
                 Some(self.hir_map.get_parent(impl_item.id)),
-                &sig.decl, &sig.generics,
+                &sig.decl, &impl_item.generics,
                 |this| intravisit::walk_impl_item(this, impl_item))
         } else {
             intravisit::walk_impl_item(self, impl_item);
diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index c7ec1d072d0..0799c4f7190 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -718,12 +718,10 @@ impl<'a, 'tcx> Visitor<'tcx> for Resolver<'a> {
                 _: Span,
                 node_id: NodeId) {
         let rib_kind = match function_kind {
-            FnKind::ItemFn(_, generics, ..) => {
-                self.visit_generics(generics);
+            FnKind::ItemFn(..) => {
                 ItemRibKind
             }
             FnKind::Method(_, sig, _, _) => {
-                self.visit_generics(&sig.generics);
                 MethodRibKind(!sig.decl.has_self())
             }
             FnKind::Closure(_) => ClosureRibKind(node_id),
@@ -1880,7 +1878,7 @@ impl<'a> Resolver<'a> {
                                 }
                                 TraitItemKind::Method(ref sig, _) => {
                                     let type_parameters =
-                                        HasTypeParameters(&sig.generics,
+                                        HasTypeParameters(&trait_item.generics,
                                                           MethodRibKind(!sig.decl.has_self()));
                                     this.with_type_parameter_rib(type_parameters, |this| {
                                         visit::walk_trait_item(this, trait_item)
@@ -2099,7 +2097,7 @@ impl<'a> Resolver<'a> {
                                         // We also need a new scope for the method-
                                         // specific type parameters.
                                         let type_parameters =
-                                            HasTypeParameters(&sig.generics,
+                                            HasTypeParameters(&impl_item.generics,
                                                             MethodRibKind(!sig.decl.has_self()));
                                         this.with_type_parameter_rib(type_parameters, |this| {
                                             visit::walk_impl_item(this, impl_item);
diff --git a/src/librustc_save_analysis/dump_visitor.rs b/src/librustc_save_analysis/dump_visitor.rs
index 3e730cf8365..c57d5305d80 100644
--- a/src/librustc_save_analysis/dump_visitor.rs
+++ b/src/librustc_save_analysis/dump_visitor.rs
@@ -354,23 +354,24 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
                       body: Option<&'l ast::Block>,
                       id: ast::NodeId,
                       name: ast::Ident,
+                      generics: &'l ast::Generics,
                       vis: ast::Visibility,
                       span: Span) {
         debug!("process_method: {}:{}", id, name);
 
         if let Some(mut method_data) = self.save_ctxt.get_method_data(id, name.name, span) {
 
-            let sig_str = ::make_signature(&sig.decl, &sig.generics);
+            let sig_str = ::make_signature(&sig.decl, &generics);
             if body.is_some() {
                 self.nest_tables(id, |v| {
                     v.process_formals(&sig.decl.inputs, &method_data.qualname)
                 });
             }
 
-            self.process_generic_params(&sig.generics, span, &method_data.qualname, id);
+            self.process_generic_params(&generics, span, &method_data.qualname, id);
 
             method_data.value = sig_str;
-            method_data.sig = sig::method_signature(id, name, sig, &self.save_ctxt);
+            method_data.sig = sig::method_signature(id, name, generics, sig, &self.save_ctxt);
             self.dumper.dump_def(vis == ast::Visibility::Public, method_data);
         }
 
@@ -1007,6 +1008,7 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
                                     body.as_ref().map(|x| &**x),
                                     trait_item.id,
                                     trait_item.ident,
+                                    &trait_item.generics,
                                     ast::Visibility::Public,
                                     trait_item.span);
             }
@@ -1066,6 +1068,7 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
                                     Some(body),
                                     impl_item.id,
                                     impl_item.ident,
+                                    &impl_item.generics,
                                     impl_item.vis.clone(),
                                     impl_item.span);
             }
diff --git a/src/librustc_save_analysis/sig.rs b/src/librustc_save_analysis/sig.rs
index 47e5ad6c010..88f574d513b 100644
--- a/src/librustc_save_analysis/sig.rs
+++ b/src/librustc_save_analysis/sig.rs
@@ -77,13 +77,14 @@ pub fn variant_signature(variant: &ast::Variant, scx: &SaveContext) -> Option<Si
 
 pub fn method_signature(id: NodeId,
                         ident: ast::Ident,
+                        generics: &ast::Generics,
                         m: &ast::MethodSig,
                         scx: &SaveContext)
                         -> Option<Signature> {
     if !scx.config.signatures {
         return None;
     }
-    make_method_signature(id, ident, m, scx).ok()
+    make_method_signature(id, ident, generics, m, scx).ok()
 }
 
 pub fn assoc_const_signature(id: NodeId,
@@ -895,6 +896,7 @@ fn make_assoc_const_signature(id: NodeId,
 
 fn make_method_signature(id: NodeId,
                          ident: ast::Ident,
+                         generics: &ast::Generics,
                          m: &ast::MethodSig,
                          scx: &SaveContext)
                          -> Result {
@@ -915,7 +917,7 @@ fn make_method_signature(id: NodeId,
 
     let mut sig = name_and_generics(text,
                                     0,
-                                    &m.generics,
+                                    generics,
                                     id,
                                     ident,
                                     scx)?;
diff --git a/src/librustc_typeck/check/compare_method.rs b/src/librustc_typeck/check/compare_method.rs
index b21d4888612..554a858bcc1 100644
--- a/src/librustc_typeck/check/compare_method.rs
+++ b/src/librustc_typeck/check/compare_method.rs
@@ -568,15 +568,11 @@ fn compare_number_of_generics<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     let num_trait_m_type_params = trait_m_generics.types.len();
     if num_impl_m_type_params != num_trait_m_type_params {
         let impl_m_node_id = tcx.hir.as_local_node_id(impl_m.def_id).unwrap();
-        let span = match tcx.hir.expect_impl_item(impl_m_node_id).node {
-            ImplItemKind::Method(ref impl_m_sig, _) => {
-                if impl_m_sig.generics.is_parameterized() {
-                    impl_m_sig.generics.span
-                } else {
-                    impl_m_span
-                }
-            }
-            _ => bug!("{:?} is not a method", impl_m),
+        let impl_m_item = tcx.hir.expect_impl_item(impl_m_node_id);
+        let span = if impl_m_item.generics.is_parameterized() {
+            impl_m_item.generics.span
+        } else {
+            impl_m_span
         };
 
         let mut err = struct_span_err!(tcx.sess,
diff --git a/src/librustc_typeck/collect.rs b/src/librustc_typeck/collect.rs
index a5b3f8cb806..68ba1b4c44c 100644
--- a/src/librustc_typeck/collect.rs
+++ b/src/librustc_typeck/collect.rs
@@ -261,19 +261,9 @@ fn type_param_predicates<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
     let item_node_id = tcx.hir.as_local_node_id(item_def_id).unwrap();
     let ast_generics = match tcx.hir.get(item_node_id) {
-        NodeTraitItem(item) => {
-            match item.node {
-                TraitItemKind::Method(ref sig, _) => &sig.generics,
-                _ => return result
-            }
-        }
+        NodeTraitItem(item) => &item.generics,
 
-        NodeImplItem(item) => {
-            match item.node {
-                ImplItemKind::Method(ref sig, _) => &sig.generics,
-                _ => return result
-            }
-        }
+        NodeImplItem(item) => &item.generics,
 
         NodeItem(item) => {
             match item.node {
@@ -818,12 +808,12 @@ fn has_late_bound_regions<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     match node {
         hir_map::NodeTraitItem(item) => match item.node {
             hir::TraitItemKind::Method(ref sig, _) =>
-                has_late_bound_regions(tcx, &sig.generics, &sig.decl),
+                has_late_bound_regions(tcx, &item.generics, &sig.decl),
             _ => None,
         },
         hir_map::NodeImplItem(item) => match item.node {
             hir::ImplItemKind::Method(ref sig, _) =>
-                has_late_bound_regions(tcx, &sig.generics, &sig.decl),
+                has_late_bound_regions(tcx, &item.generics, &sig.decl),
             _ => None,
         },
         hir_map::NodeForeignItem(item) => match item.node {
@@ -881,19 +871,9 @@ fn generics_of<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
     let no_generics = hir::Generics::empty();
     let ast_generics = match node {
-        NodeTraitItem(item) => {
-            match item.node {
-                TraitItemKind::Method(ref sig, _) => &sig.generics,
-                _ => &no_generics
-            }
-        }
+        NodeTraitItem(item) => &item.generics,
 
-        NodeImplItem(item) => {
-            match item.node {
-                ImplItemKind::Method(ref sig, _) => &sig.generics,
-                _ => &no_generics
-            }
-        }
+        NodeImplItem(item) => &item.generics,
 
         NodeItem(item) => {
             match item.node {
@@ -1353,19 +1333,9 @@ fn explicit_predicates_of<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     let icx = ItemCtxt::new(tcx, def_id);
     let no_generics = hir::Generics::empty();
     let ast_generics = match node {
-        NodeTraitItem(item) => {
-            match item.node {
-                TraitItemKind::Method(ref sig, _) => &sig.generics,
-                _ => &no_generics
-            }
-        }
+        NodeTraitItem(item) => &item.generics,
 
-        NodeImplItem(item) => {
-            match item.node {
-                ImplItemKind::Method(ref sig, _) => &sig.generics,
-                _ => &no_generics
-            }
-        }
+        NodeImplItem(item) => &item.generics,
 
         NodeItem(item) => {
             match item.node {
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index ad171c4babb..4e8bf5f9109 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -1141,13 +1141,13 @@ pub struct Method {
     pub abi: Abi,
 }
 
-impl<'a> Clean<Method> for (&'a hir::MethodSig, hir::BodyId) {
+impl<'a> Clean<Method> for (&'a hir::MethodSig, &'a hir::Generics, hir::BodyId) {
     fn clean(&self, cx: &DocContext) -> Method {
         Method {
-            generics: self.0.generics.clean(cx),
+            generics: self.1.clean(cx),
             unsafety: self.0.unsafety,
             constness: self.0.constness,
-            decl: (&*self.0.decl, self.1).clean(cx),
+            decl: (&*self.0.decl, self.2).clean(cx),
             abi: self.0.abi
         }
     }
@@ -1380,13 +1380,13 @@ impl Clean<Item> for hir::TraitItem {
                                     default.map(|e| print_const_expr(cx, e)))
             }
             hir::TraitItemKind::Method(ref sig, hir::TraitMethod::Provided(body)) => {
-                MethodItem((sig, body).clean(cx))
+                MethodItem((sig, &self.generics, body).clean(cx))
             }
             hir::TraitItemKind::Method(ref sig, hir::TraitMethod::Required(ref names)) => {
                 TyMethodItem(TyMethod {
                     unsafety: sig.unsafety.clone(),
                     decl: (&*sig.decl, &names[..]).clean(cx),
-                    generics: sig.generics.clean(cx),
+                    generics: self.generics.clean(cx),
                     abi: sig.abi
                 })
             }
@@ -1415,7 +1415,7 @@ impl Clean<Item> for hir::ImplItem {
                                     Some(print_const_expr(cx, expr)))
             }
             hir::ImplItemKind::Method(ref sig, body) => {
-                MethodItem((sig, body).clean(cx))
+                MethodItem((sig, &self.generics, body).clean(cx))
             }
             hir::ImplItemKind::Type(ref ty) => TypedefItem(Typedef {
                 type_: ty.clean(cx),
diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index f445def9e03..b985ac78056 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -1178,7 +1178,6 @@ pub struct MethodSig {
     pub constness: Spanned<Constness>,
     pub abi: Abi,
     pub decl: P<FnDecl>,
-    pub generics: Generics,
 }
 
 /// Represents an item declaration within a trait declaration,
@@ -1190,6 +1189,7 @@ pub struct TraitItem {
     pub id: NodeId,
     pub ident: Ident,
     pub attrs: Vec<Attribute>,
+    pub generics: Generics,
     pub node: TraitItemKind,
     pub span: Span,
     /// See `Item::tokens` for what this is
@@ -1211,6 +1211,7 @@ pub struct ImplItem {
     pub vis: Visibility,
     pub defaultness: Defaultness,
     pub attrs: Vec<Attribute>,
+    pub generics: Generics,
     pub node: ImplItemKind,
     pub span: Span,
     /// See `Item::tokens` for what this is
diff --git a/src/libsyntax/ext/placeholders.rs b/src/libsyntax/ext/placeholders.rs
index 4fc2b92d3cd..2f5b386346b 100644
--- a/src/libsyntax/ext/placeholders.rs
+++ b/src/libsyntax/ext/placeholders.rs
@@ -32,6 +32,7 @@ pub fn placeholder(kind: ExpansionKind, id: ast::NodeId) -> Expansion {
 
     let ident = keywords::Invalid.ident();
     let attrs = Vec::new();
+    let generics = ast::Generics::default();
     let vis = ast::Visibility::Inherited;
     let span = DUMMY_SP;
     let expr_placeholder = || P(ast::Expr {
@@ -49,12 +50,12 @@ pub fn placeholder(kind: ExpansionKind, id: ast::NodeId) -> Expansion {
             tokens: None,
         }))),
         ExpansionKind::TraitItems => Expansion::TraitItems(SmallVector::one(ast::TraitItem {
-            id, span, ident, attrs,
+            id, span, ident, attrs, generics,
             node: ast::TraitItemKind::Macro(mac_placeholder()),
             tokens: None,
         })),
         ExpansionKind::ImplItems => Expansion::ImplItems(SmallVector::one(ast::ImplItem {
-            id, span, ident, vis, attrs,
+            id, span, ident, vis, attrs, generics,
             node: ast::ImplItemKind::Macro(mac_placeholder()),
             defaultness: ast::Defaultness::Final,
             tokens: None,
diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 9060a613bc1..326f8cef6b3 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -1526,7 +1526,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
                 span: Span,
                 _node_id: NodeId) {
         // check for const fn declarations
-        if let FnKind::ItemFn(_, _, _, Spanned { node: ast::Constness::Const, .. }, _, _, _) =
+        if let FnKind::ItemFn(_, _, Spanned { node: ast::Constness::Const, .. }, _, _, _) =
             fn_kind {
             gate_feature_post!(&self, const_fn, span, "const fn is unstable");
         }
@@ -1536,7 +1536,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
         // point.
 
         match fn_kind {
-            FnKind::ItemFn(_, _, _, _, abi, _, _) |
+            FnKind::ItemFn(_, _, _, abi, _, _) |
             FnKind::Method(_, &ast::MethodSig { abi, .. }, _, _) => {
                 self.check_abi(abi, span);
             }
diff --git a/src/libsyntax/fold.rs b/src/libsyntax/fold.rs
index d7d491db71f..518386a2ad2 100644
--- a/src/libsyntax/fold.rs
+++ b/src/libsyntax/fold.rs
@@ -943,6 +943,7 @@ pub fn noop_fold_trait_item<T: Folder>(i: TraitItem, folder: &mut T)
         id: folder.new_id(i.id),
         ident: folder.fold_ident(i.ident),
         attrs: fold_attrs(i.attrs, folder),
+        generics: folder.fold_generics(i.generics),
         node: match i.node {
             TraitItemKind::Const(ty, default) => {
                 TraitItemKind::Const(folder.fold_ty(ty),
@@ -972,6 +973,7 @@ pub fn noop_fold_impl_item<T: Folder>(i: ImplItem, folder: &mut T)
         vis: folder.fold_vis(i.vis),
         ident: folder.fold_ident(i.ident),
         attrs: fold_attrs(i.attrs, folder),
+        generics: folder.fold_generics(i.generics),
         defaultness: i.defaultness,
         node: match i.node  {
             ast::ImplItemKind::Const(ty, expr) => {
@@ -1074,7 +1076,6 @@ pub fn noop_fold_foreign_item<T: Folder>(ni: ForeignItem, folder: &mut T) -> For
 
 pub fn noop_fold_method_sig<T: Folder>(sig: MethodSig, folder: &mut T) -> MethodSig {
     MethodSig {
-        generics: folder.fold_generics(sig.generics),
         abi: sig.abi,
         unsafety: sig.unsafety,
         constness: sig.constness,
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 8fd2bad4e44..07fa2a4d1a7 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -1287,10 +1287,10 @@ impl<'a> Parser<'a> {
                          mut attrs: Vec<Attribute>) -> PResult<'a, TraitItem> {
         let lo = self.span;
 
-        let (name, node) = if self.eat_keyword(keywords::Type) {
+        let (name, node, generics) = if self.eat_keyword(keywords::Type) {
             let TyParam {ident, bounds, default, ..} = self.parse_ty_param(vec![])?;
             self.expect(&token::Semi)?;
-            (ident, TraitItemKind::Type(bounds, default))
+            (ident, TraitItemKind::Type(bounds, default), ast::Generics::default())
         } else if self.is_const_item() {
             self.expect_keyword(keywords::Const)?;
             let ident = self.parse_ident()?;
@@ -1305,7 +1305,7 @@ impl<'a> Parser<'a> {
                 self.expect(&token::Semi)?;
                 None
             };
-            (ident, TraitItemKind::Const(ty, default))
+            (ident, TraitItemKind::Const(ty, default), ast::Generics::default())
         } else if self.token.is_path_start() {
             // trait item macro.
             // code copied from parse_macro_use_or_failure... abstraction!
@@ -1328,7 +1328,7 @@ impl<'a> Parser<'a> {
             }
 
             let mac = respan(lo.to(self.prev_span), Mac_ { path: pth, tts: tts });
-            (keywords::Invalid.ident(), ast::TraitItemKind::Macro(mac))
+            (keywords::Invalid.ident(), ast::TraitItemKind::Macro(mac), ast::Generics::default())
         } else {
             let (constness, unsafety, abi) = self.parse_fn_front_matter()?;
 
@@ -1341,13 +1341,12 @@ impl<'a> Parser<'a> {
                 // definition...
                 p.parse_arg_general(false)
             })?;
-
             generics.where_clause = self.parse_where_clause()?;
+
             let sig = ast::MethodSig {
                 unsafety,
                 constness,
                 decl: d,
-                generics,
                 abi,
             };
 
@@ -1370,13 +1369,14 @@ impl<'a> Parser<'a> {
                     return Err(self.fatal(&format!("expected `;` or `{{`, found `{}`", token_str)));
                 }
             };
-            (ident, ast::TraitItemKind::Method(sig, body))
+            (ident, ast::TraitItemKind::Method(sig, body), generics)
         };
 
         Ok(TraitItem {
             id: ast::DUMMY_NODE_ID,
             ident: name,
             attrs,
+            generics,
             node,
             span: lo.to(self.prev_span),
             tokens: None,
@@ -4901,12 +4901,12 @@ impl<'a> Parser<'a> {
         let lo = self.span;
         let vis = self.parse_visibility(false)?;
         let defaultness = self.parse_defaultness()?;
-        let (name, node) = if self.eat_keyword(keywords::Type) {
+        let (name, node, generics) = if self.eat_keyword(keywords::Type) {
             let name = self.parse_ident()?;
             self.expect(&token::Eq)?;
             let typ = self.parse_ty()?;
             self.expect(&token::Semi)?;
-            (name, ast::ImplItemKind::Type(typ))
+            (name, ast::ImplItemKind::Type(typ), ast::Generics::default())
         } else if self.is_const_item() {
             self.expect_keyword(keywords::Const)?;
             let name = self.parse_ident()?;
@@ -4915,11 +4915,11 @@ impl<'a> Parser<'a> {
             self.expect(&token::Eq)?;
             let expr = self.parse_expr()?;
             self.expect(&token::Semi)?;
-            (name, ast::ImplItemKind::Const(typ, expr))
+            (name, ast::ImplItemKind::Const(typ, expr), ast::Generics::default())
         } else {
-            let (name, inner_attrs, node) = self.parse_impl_method(&vis, at_end)?;
+            let (name, inner_attrs, generics, node) = self.parse_impl_method(&vis, at_end)?;
             attrs.extend(inner_attrs);
-            (name, node)
+            (name, node, generics)
         };
 
         Ok(ImplItem {
@@ -4929,6 +4929,7 @@ impl<'a> Parser<'a> {
             vis,
             defaultness,
             attrs,
+            generics,
             node,
             tokens: None,
         })
@@ -4986,7 +4987,8 @@ impl<'a> Parser<'a> {
 
     /// Parse a method or a macro invocation in a trait impl.
     fn parse_impl_method(&mut self, vis: &Visibility, at_end: &mut bool)
-                         -> PResult<'a, (Ident, Vec<ast::Attribute>, ast::ImplItemKind)> {
+                         -> PResult<'a, (Ident, Vec<ast::Attribute>, ast::Generics,
+                             ast::ImplItemKind)> {
         // code copied from parse_macro_use_or_failure... abstraction!
         if self.token.is_path_start() {
             // Method macro.
@@ -5013,7 +5015,8 @@ impl<'a> Parser<'a> {
             }
 
             let mac = respan(lo.to(self.prev_span), Mac_ { path: pth, tts: tts });
-            Ok((keywords::Invalid.ident(), vec![], ast::ImplItemKind::Macro(mac)))
+            Ok((keywords::Invalid.ident(), vec![], ast::Generics::default(),
+                ast::ImplItemKind::Macro(mac)))
         } else {
             let (constness, unsafety, abi) = self.parse_fn_front_matter()?;
             let ident = self.parse_ident()?;
@@ -5022,8 +5025,7 @@ impl<'a> Parser<'a> {
             generics.where_clause = self.parse_where_clause()?;
             *at_end = true;
             let (inner_attrs, body) = self.parse_inner_attrs_and_block()?;
-            Ok((ident, inner_attrs, ast::ImplItemKind::Method(ast::MethodSig {
-                generics,
+            Ok((ident, inner_attrs, generics, ast::ImplItemKind::Method(ast::MethodSig {
                 abi,
                 unsafety,
                 constness,
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index 02f871c58c7..b9a7fa04a06 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -1525,6 +1525,7 @@ impl<'a> State<'a> {
 
     pub fn print_method_sig(&mut self,
                             ident: ast::Ident,
+                            generics: &ast::Generics,
                             m: &ast::MethodSig,
                             vis: &ast::Visibility)
                             -> io::Result<()> {
@@ -1533,7 +1534,7 @@ impl<'a> State<'a> {
                       m.constness.node,
                       m.abi,
                       Some(ident),
-                      &m.generics,
+                      &generics,
                       vis)
     }
 
@@ -1553,7 +1554,7 @@ impl<'a> State<'a> {
                 if body.is_some() {
                     self.head("")?;
                 }
-                self.print_method_sig(ti.ident, sig, &ast::Visibility::Inherited)?;
+                self.print_method_sig(ti.ident, &ti.generics, sig, &ast::Visibility::Inherited)?;
                 if let Some(ref body) = *body {
                     self.nbsp()?;
                     self.print_block_with_attrs(body, &ti.attrs)?;
@@ -1592,7 +1593,7 @@ impl<'a> State<'a> {
             }
             ast::ImplItemKind::Method(ref sig, ref body) => {
                 self.head("")?;
-                self.print_method_sig(ii.ident, sig, &ii.vis)?;
+                self.print_method_sig(ii.ident, &ii.generics, sig, &ii.vis)?;
                 self.nbsp()?;
                 self.print_block_with_attrs(body, &ii.attrs)?;
             }
diff --git a/src/libsyntax/visit.rs b/src/libsyntax/visit.rs
index 521c6030eba..078a63cba20 100644
--- a/src/libsyntax/visit.rs
+++ b/src/libsyntax/visit.rs
@@ -31,7 +31,7 @@ use codemap::Spanned;
 #[derive(Copy, Clone, PartialEq, Eq)]
 pub enum FnKind<'a> {
     /// fn foo() or extern "Abi" fn foo()
-    ItemFn(Ident, &'a Generics, Unsafety, Spanned<Constness>, Abi, &'a Visibility, &'a Block),
+    ItemFn(Ident, Unsafety, Spanned<Constness>, Abi, &'a Visibility, &'a Block),
 
     /// fn foo(&self)
     Method(Ident, &'a MethodSig, Option<&'a Visibility>, &'a Block),
@@ -247,7 +247,8 @@ pub fn walk_item<'a, V: Visitor<'a>>(visitor: &mut V, item: &'a Item) {
             visitor.visit_expr(expr);
         }
         ItemKind::Fn(ref declaration, unsafety, constness, abi, ref generics, ref body) => {
-            visitor.visit_fn(FnKind::ItemFn(item.ident, generics, unsafety,
+            visitor.visit_generics(generics);
+            visitor.visit_fn(FnKind::ItemFn(item.ident, unsafety,
                                             constness, abi, &item.vis, body),
                              declaration,
                              item.span,
@@ -538,13 +539,11 @@ pub fn walk_fn<'a, V>(visitor: &mut V, kind: FnKind<'a>, declaration: &'a FnDecl
     where V: Visitor<'a>,
 {
     match kind {
-        FnKind::ItemFn(_, generics, _, _, _, _, body) => {
-            visitor.visit_generics(generics);
+        FnKind::ItemFn(_, _, _, _, _, body) => {
             walk_fn_decl(visitor, declaration);
             visitor.visit_block(body);
         }
-        FnKind::Method(_, sig, _, body) => {
-            visitor.visit_generics(&sig.generics);
+        FnKind::Method(_, _, _, body) => {
             walk_fn_decl(visitor, declaration);
             visitor.visit_block(body);
         }
@@ -558,13 +557,13 @@ pub fn walk_fn<'a, V>(visitor: &mut V, kind: FnKind<'a>, declaration: &'a FnDecl
 pub fn walk_trait_item<'a, V: Visitor<'a>>(visitor: &mut V, trait_item: &'a TraitItem) {
     visitor.visit_ident(trait_item.span, trait_item.ident);
     walk_list!(visitor, visit_attribute, &trait_item.attrs);
+    visitor.visit_generics(&trait_item.generics);
     match trait_item.node {
         TraitItemKind::Const(ref ty, ref default) => {
             visitor.visit_ty(ty);
             walk_list!(visitor, visit_expr, default);
         }
         TraitItemKind::Method(ref sig, None) => {
-            visitor.visit_generics(&sig.generics);
             walk_fn_decl(visitor, &sig.decl);
         }
         TraitItemKind::Method(ref sig, Some(ref body)) => {
@@ -585,6 +584,7 @@ pub fn walk_impl_item<'a, V: Visitor<'a>>(visitor: &mut V, impl_item: &'a ImplIt
     visitor.visit_vis(&impl_item.vis);
     visitor.visit_ident(impl_item.span, impl_item.ident);
     walk_list!(visitor, visit_attribute, &impl_item.attrs);
+    visitor.visit_generics(&impl_item.generics);
     match impl_item.node {
         ImplItemKind::Const(ref ty, ref expr) => {
             visitor.visit_ty(ty);
diff --git a/src/libsyntax_ext/deriving/generic/mod.rs b/src/libsyntax_ext/deriving/generic/mod.rs
index 5c1ca19d635..18897047538 100644
--- a/src/libsyntax_ext/deriving/generic/mod.rs
+++ b/src/libsyntax_ext/deriving/generic/mod.rs
@@ -506,6 +506,7 @@ impl<'a> TraitDef<'a> {
                 vis: ast::Visibility::Inherited,
                 defaultness: ast::Defaultness::Final,
                 attrs: Vec::new(),
+                generics: Generics::default(),
                 node: ast::ImplItemKind::Type(type_def.to_ty(cx, self.span, type_ident, generics)),
                 tokens: None,
             }
@@ -921,12 +922,12 @@ impl<'a> MethodDef<'a> {
         ast::ImplItem {
             id: ast::DUMMY_NODE_ID,
             attrs: self.attributes.clone(),
+            generics: fn_generics,
             span: trait_.span,
             vis: ast::Visibility::Inherited,
             defaultness: ast::Defaultness::Final,
             ident: method_ident,
             node: ast::ImplItemKind::Method(ast::MethodSig {
-                                                generics: fn_generics,
                                                 abi,
                                                 unsafety,
                                                 constness:
diff --git a/src/test/incremental/hashes/inherent_impls.rs b/src/test/incremental/hashes/inherent_impls.rs
index 5067b571ee6..9351a4b05f1 100644
--- a/src/test/incremental/hashes/inherent_impls.rs
+++ b/src/test/incremental/hashes/inherent_impls.rs
@@ -370,9 +370,7 @@ impl Foo {
 #[rustc_metadata_clean(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
 impl Foo {
-    // FIXME(michaelwoerister): This is curious but an unused lifetime parameter doesn't seem to
-    // show up in any of the derived data structures.
-    #[rustc_clean(cfg="cfail2", except="Hir,HirBody")]
+    #[rustc_clean(cfg="cfail2", except="Hir,HirBody,TypeckTables")]
     #[rustc_clean(cfg="cfail3")]
     #[rustc_metadata_clean(cfg="cfail2")]
     #[rustc_metadata_clean(cfg="cfail3")]
@@ -395,7 +393,7 @@ impl Foo {
 impl Foo {
     #[rustc_clean(
         cfg="cfail2",
-        except="Hir,HirBody,GenericsOfItem,PredicatesOfItem,TypeOfItem",
+        except="Hir,HirBody,GenericsOfItem,PredicatesOfItem,TypeOfItem,TypeckTables",
     )]
     #[rustc_clean(cfg="cfail3")]
     #[rustc_metadata_dirty(cfg="cfail2")]
@@ -441,7 +439,8 @@ impl Foo {
 #[rustc_metadata_clean(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
 impl Foo {
-    #[rustc_clean(cfg="cfail2", except="Hir,HirBody,GenericsOfItem,PredicatesOfItem,TypeOfItem")]
+    #[rustc_clean(cfg="cfail2", except="Hir,HirBody,GenericsOfItem,PredicatesOfItem,\
+                                        TypeOfItem,TypeckTables")]
     #[rustc_clean(cfg="cfail3")]
     #[rustc_metadata_dirty(cfg="cfail2")]
     #[rustc_metadata_clean(cfg="cfail3")]
@@ -462,7 +461,7 @@ impl Foo {
 #[rustc_metadata_clean(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
 impl Foo {
-    #[rustc_clean(cfg="cfail2", except="Hir,HirBody,PredicatesOfItem")]
+    #[rustc_clean(cfg="cfail2", except="Hir,HirBody,PredicatesOfItem,TypeckTables")]
     #[rustc_clean(cfg="cfail3")]
     #[rustc_metadata_dirty(cfg="cfail2")]
     #[rustc_metadata_clean(cfg="cfail3")]
diff --git a/src/tools/toolstate.toml b/src/tools/toolstate.toml
index e62597c5216..9dd420c1458 100644
--- a/src/tools/toolstate.toml
+++ b/src/tools/toolstate.toml
@@ -26,10 +26,10 @@
 miri = "Broken"
 
 # ping @Manishearth @llogiq @mcarton @oli-obk
-clippy = "Compiling"
+clippy = "Broken"
 
 # ping @nrc
-rls = "Testing"
+rls = "Broken"
 
 # ping @nrc
-rustfmt = "Testing"
+rustfmt = "Broken"