rustc: Remove the TyCtxt field from ParameterEnvironment.

8 files changed, 43 insertions, 48 deletions

diff --git a/src/librustc/infer/mod.rs b/src/librustc/infer/mod.rs
index cef2ae12d6b..ffd7e9a7772 100644
--- a/src/librustc/infer/mod.rs
+++ b/src/librustc/infer/mod.rs
@@ -92,7 +92,7 @@ pub struct InferCtxt<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {
     // For region variables.
     region_vars: RegionVarBindings<'a, 'tcx>,
 
-    pub parameter_environment: ty::ParameterEnvironment<'a, 'tcx>,
+    pub parameter_environment: ty::ParameterEnvironment<'gcx>,
 
     // the set of predicates on which errors have been reported, to
     // avoid reporting the same error twice.
@@ -387,7 +387,7 @@ impl fmt::Display for FixupError {
 impl<'a, 'tcx> InferCtxt<'a, 'tcx, 'tcx> {
     pub fn new(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                tables: &'a RefCell<ty::Tables<'tcx>>,
-               param_env: Option<ty::ParameterEnvironment<'a, 'tcx>>,
+               param_env: Option<ty::ParameterEnvironment<'tcx>>,
                projection_mode: ProjectionMode)
                -> Self {
         InferCtxt {
@@ -1440,7 +1440,7 @@ pub fn drain_fulfillment_cx<T>(&self,
             // cases.
             !traits::type_known_to_meet_builtin_bound(self, ty, ty::BoundCopy, span)
         } else {
-            ty.moves_by_default(&self.parameter_environment, span)
+            ty.moves_by_default(self.tcx, &self.parameter_environment, span)
         }
     }
 
@@ -1484,7 +1484,7 @@ pub fn drain_fulfillment_cx<T>(&self,
         self.tables.borrow().upvar_capture_map.get(&upvar_id).cloned()
     }
 
-    pub fn param_env<'b>(&'b self) -> &'b ty::ParameterEnvironment<'b,'tcx> {
+    pub fn param_env(&self) -> &ty::ParameterEnvironment<'tcx> {
         &self.parameter_environment
     }
 
diff --git a/src/librustc/traits/mod.rs b/src/librustc/traits/mod.rs
index 25710e86f60..063d6427f08 100644
--- a/src/librustc/traits/mod.rs
+++ b/src/librustc/traits/mod.rs
@@ -18,7 +18,7 @@ pub use self::ObligationCauseCode::*;
 use hir::def_id::DefId;
 use middle::free_region::FreeRegionMap;
 use ty::subst;
-use ty::{self, Ty, TypeFoldable};
+use ty::{self, Ty, TyCtxt, TypeFoldable};
 use infer::InferCtxt;
 
 use std::rc::Rc;
@@ -378,9 +378,10 @@ pub fn type_known_to_meet_builtin_bound<'a,'tcx>(infcx: &InferCtxt<'a,'tcx, 'tcx
 
 // FIXME: this is gonna need to be removed ...
 /// Normalizes the parameter environment, reporting errors if they occur.
-pub fn normalize_param_env_or_error<'a,'tcx>(unnormalized_env: ty::ParameterEnvironment<'a,'tcx>,
-                                             cause: ObligationCause<'tcx>)
-                                             -> ty::ParameterEnvironment<'a,'tcx>
+pub fn normalize_param_env_or_error<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
+    unnormalized_env: ty::ParameterEnvironment<'tcx>,
+    cause: ObligationCause<'tcx>)
+    -> ty::ParameterEnvironment<'tcx>
 {
     // I'm not wild about reporting errors here; I'd prefer to
     // have the errors get reported at a defined place (e.g.,
@@ -397,7 +398,6 @@ pub fn normalize_param_env_or_error<'a,'tcx>(unnormalized_env: ty::ParameterEnvi
     // and errors will get reported then; so after typeck we
     // can be sure that no errors should occur.
 
-    let tcx = unnormalized_env.tcx;
     let span = cause.span;
     let body_id = cause.body_id;
 
diff --git a/src/librustc/traits/select.rs b/src/librustc/traits/select.rs
index eda9587f98e..ad1a7baadf9 100644
--- a/src/librustc/traits/select.rs
+++ b/src/librustc/traits/select.rs
@@ -287,7 +287,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx, 'tcx> {
         self.infcx.tcx
     }
 
-    pub fn param_env(&self) -> &'cx ty::ParameterEnvironment<'cx, 'tcx> {
+    pub fn param_env(&self) -> &'cx ty::ParameterEnvironment<'tcx> {
         self.infcx.param_env()
     }
 
diff --git a/src/librustc/ty/layout.rs b/src/librustc/ty/layout.rs
index 9c9da6960e7..a7e253a45aa 100644
--- a/src/librustc/ty/layout.rs
+++ b/src/librustc/ty/layout.rs
@@ -790,7 +790,7 @@ impl<'a, 'tcx> Layout {
             ty::TyRef(_, ty::TypeAndMut { ty: pointee, .. }) |
             ty::TyRawPtr(ty::TypeAndMut { ty: pointee, .. }) => {
                 let non_zero = !ty.is_unsafe_ptr();
-                if pointee.is_sized(&infcx.parameter_environment, DUMMY_SP) {
+                if pointee.is_sized(tcx, &infcx.parameter_environment, DUMMY_SP) {
                     Scalar { value: Pointer, non_zero: non_zero }
                 } else {
                     let unsized_part = tcx.struct_tail(pointee);
@@ -883,7 +883,7 @@ impl<'a, 'tcx> Layout {
                 // the unsized field. Several other pieces of code assume that the unsized
                 // field is definitely the last one.
                 if def.dtor_kind().has_drop_flag() &&
-                   ty.is_sized(&infcx.parameter_environment, DUMMY_SP) {
+                   ty.is_sized(tcx, &infcx.parameter_environment, DUMMY_SP) {
                     st.extend(dl, Some(Ok(&Scalar {
                         value: Int(I8),
                         non_zero: false
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index 5e860eeedf4..a65280bd012 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -1209,9 +1209,7 @@ impl<'tcx> TraitRef<'tcx> {
 /// future I hope to refine the representation of types so as to make
 /// more distinctions clearer.
 #[derive(Clone)]
-pub struct ParameterEnvironment<'a, 'tcx:'a> {
-    pub tcx: TyCtxt<'a, 'tcx, 'tcx>,
-
+pub struct ParameterEnvironment<'tcx> {
     /// See `construct_free_substs` for details.
     pub free_substs: Substs<'tcx>,
 
@@ -1243,13 +1241,12 @@ pub struct ParameterEnvironment<'a, 'tcx:'a> {
     pub free_id_outlive: CodeExtent,
 }
 
-impl<'a, 'tcx> ParameterEnvironment<'a, 'tcx> {
+impl<'a, 'tcx> ParameterEnvironment<'tcx> {
     pub fn with_caller_bounds(&self,
                               caller_bounds: Vec<ty::Predicate<'tcx>>)
-                              -> ParameterEnvironment<'a,'tcx>
+                              -> ParameterEnvironment<'tcx>
     {
         ParameterEnvironment {
-            tcx: self.tcx,
             free_substs: self.free_substs.clone(),
             implicit_region_bound: self.implicit_region_bound,
             caller_bounds: caller_bounds,
@@ -1260,7 +1257,8 @@ impl<'a, 'tcx> ParameterEnvironment<'a, 'tcx> {
     }
 
     /// Construct a parameter environment given an item, impl item, or trait item
-    pub fn for_item(tcx: TyCtxt<'a, 'tcx, 'tcx>, id: NodeId) -> ParameterEnvironment<'a, 'tcx> {
+    pub fn for_item(tcx: TyCtxt<'a, 'tcx, 'tcx>, id: NodeId)
+                    -> ParameterEnvironment<'tcx> {
         match tcx.map.find(id) {
             Some(ast_map::NodeImplItem(ref impl_item)) => {
                 match impl_item.node {
@@ -2546,14 +2544,14 @@ impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
     ///
     /// (Note that this implies that if `ty` has a destructor attached,
     /// then `type_needs_drop` will definitely return `true` for `ty`.)
-    pub fn type_needs_drop_given_env<'b>(self,
-                                         ty: Ty<'tcx>,
-                                         param_env: &ty::ParameterEnvironment<'b,'tcx>) -> bool {
+    pub fn type_needs_drop_given_env(self,
+                                     ty: Ty<'tcx>,
+                                     param_env: &ty::ParameterEnvironment<'tcx>) -> bool {
         // Issue #22536: We first query type_moves_by_default.  It sees a
         // normalized version of the type, and therefore will definitely
         // know whether the type implements Copy (and thus needs no
         // cleanup/drop/zeroing) ...
-        let implements_copy = !ty.moves_by_default(param_env, DUMMY_SP);
+        let implements_copy = !ty.moves_by_default(self, param_env, DUMMY_SP);
 
         if implements_copy { return false; }
 
@@ -2803,13 +2801,12 @@ impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
 
     /// Construct a parameter environment suitable for static contexts or other contexts where there
     /// are no free type/lifetime parameters in scope.
-    pub fn empty_parameter_environment(self) -> ParameterEnvironment<'a,'tcx> {
+    pub fn empty_parameter_environment(self) -> ParameterEnvironment<'tcx> {
 
         // for an empty parameter environment, there ARE no free
         // regions, so it shouldn't matter what we use for the free id
         let free_id_outlive = self.region_maps.node_extent(ast::DUMMY_NODE_ID);
-        ty::ParameterEnvironment { tcx: self,
-                                   free_substs: Substs::empty(),
+        ty::ParameterEnvironment { free_substs: Substs::empty(),
                                    caller_bounds: Vec::new(),
                                    implicit_region_bound: ty::ReEmpty,
                                    selection_cache: traits::SelectionCache::new(),
@@ -2856,7 +2853,7 @@ impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
                                            generics: &ty::Generics<'tcx>,
                                            generic_predicates: &ty::GenericPredicates<'tcx>,
                                            free_id_outlive: CodeExtent)
-                                           -> ParameterEnvironment<'a, 'tcx>
+                                           -> ParameterEnvironment<'tcx>
     {
         //
         // Construct the free substs.
@@ -2886,7 +2883,6 @@ impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
         //
 
         let unnormalized_env = ty::ParameterEnvironment {
-            tcx: self,
             free_substs: free_substs,
             implicit_region_bound: ty::ReScope(free_id_outlive),
             caller_bounds: predicates,
@@ -2896,7 +2892,7 @@ impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
         };
 
         let cause = traits::ObligationCause::misc(span, free_id_outlive.node_id(&self.region_maps));
-        traits::normalize_param_env_or_error(unnormalized_env, cause)
+        traits::normalize_param_env_or_error(self, unnormalized_env, cause)
     }
 
     pub fn is_method_call(self, expr_id: NodeId) -> bool {
diff --git a/src/librustc/ty/structural_impls.rs b/src/librustc/ty/structural_impls.rs
index e715732ceb2..811b9238729 100644
--- a/src/librustc/ty/structural_impls.rs
+++ b/src/librustc/ty/structural_impls.rs
@@ -758,10 +758,9 @@ impl<'tcx> TypeFoldable<'tcx> for ty::ClosureUpvar<'tcx> {
     }
 }
 
-impl<'a, 'tcx> TypeFoldable<'tcx> for ty::ParameterEnvironment<'a, 'tcx> where 'tcx: 'a {
+impl<'tcx> TypeFoldable<'tcx> for ty::ParameterEnvironment<'tcx> {
     fn super_fold_with<F:TypeFolder<'tcx>>(&self, folder: &mut F) -> Self {
         ty::ParameterEnvironment {
-            tcx: self.tcx,
             free_substs: self.free_substs.fold_with(folder),
             implicit_region_bound: self.implicit_region_bound.fold_with(folder),
             caller_bounds: self.caller_bounds.fold_with(folder),
diff --git a/src/librustc/ty/util.rs b/src/librustc/ty/util.rs
index 8402efcabc6..b2b0437a933 100644
--- a/src/librustc/ty/util.rs
+++ b/src/librustc/ty/util.rs
@@ -129,11 +129,10 @@ pub enum Representability {
     SelfRecursive,
 }
 
-impl<'a, 'tcx> ParameterEnvironment<'a, 'tcx> {
-    pub fn can_type_implement_copy(&self, self_type: Ty<'tcx>, span: Span)
-                                   -> Result<(),CopyImplementationError> {
-        let tcx = self.tcx;
-
+impl<'tcx> ParameterEnvironment<'tcx> {
+    pub fn can_type_implement_copy<'a>(&self, tcx: TyCtxt<'a, 'tcx, 'tcx>,
+                                       self_type: Ty<'tcx>, span: Span)
+                                       -> Result<(),CopyImplementationError> {
         // FIXME: (@jroesch) float this code up
         let infcx = InferCtxt::new(tcx, &tcx.tables, Some(self.clone()),
                                    ProjectionMode::Topmost);
@@ -509,12 +508,10 @@ impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
 }
 
 impl<'a, 'tcx> ty::TyS<'tcx> {
-    fn impls_bound(&'tcx self, param_env: &ParameterEnvironment<'a, 'tcx>,
-                   bound: ty::BuiltinBound,
-                   span: Span)
-                   -> bool
+    fn impls_bound(&'tcx self, tcx: TyCtxt<'a, 'tcx, 'tcx>,
+                   param_env: &ParameterEnvironment<'tcx>,
+                   bound: ty::BuiltinBound, span: Span) -> bool
     {
-        let tcx = param_env.tcx;
         let infcx = InferCtxt::new(tcx, &tcx.tables, Some(param_env.clone()),
                                    ProjectionMode::Topmost);
 
@@ -528,7 +525,8 @@ impl<'a, 'tcx> ty::TyS<'tcx> {
     }
 
     // FIXME (@jroesch): I made this public to use it, not sure if should be private
-    pub fn moves_by_default(&'tcx self, param_env: &ParameterEnvironment<'a, 'tcx>,
+    pub fn moves_by_default(&'tcx self, tcx: TyCtxt<'a, 'tcx, 'tcx>,
+                            param_env: &ParameterEnvironment<'tcx>,
                             span: Span) -> bool {
         if self.flags.get().intersects(TypeFlags::MOVENESS_CACHED) {
             return self.flags.get().intersects(TypeFlags::MOVES_BY_DEFAULT);
@@ -550,7 +548,7 @@ impl<'a, 'tcx> ty::TyS<'tcx> {
             TyArray(..) | TySlice(_) | TyTrait(..) | TyTuple(..) |
             TyClosure(..) | TyEnum(..) | TyStruct(..) |
             TyProjection(..) | TyParam(..) | TyInfer(..) | TyError => None
-        }.unwrap_or_else(|| !self.impls_bound(param_env, ty::BoundCopy, span));
+        }.unwrap_or_else(|| !self.impls_bound(tcx, param_env, ty::BoundCopy, span));
 
         if !self.has_param_types() && !self.has_self_ty() {
             self.flags.set(self.flags.get() | if result {
@@ -564,17 +562,19 @@ impl<'a, 'tcx> ty::TyS<'tcx> {
     }
 
     #[inline]
-    pub fn is_sized(&'tcx self, param_env: &ParameterEnvironment<'a, 'tcx>,
+    pub fn is_sized(&'tcx self, tcx: TyCtxt<'a, 'tcx, 'tcx>,
+                    param_env: &ParameterEnvironment<'tcx>,
                     span: Span) -> bool
     {
         if self.flags.get().intersects(TypeFlags::SIZEDNESS_CACHED) {
             return self.flags.get().intersects(TypeFlags::IS_SIZED);
         }
 
-        self.is_sized_uncached(param_env, span)
+        self.is_sized_uncached(tcx, param_env, span)
     }
 
-    fn is_sized_uncached(&'tcx self, param_env: &ParameterEnvironment<'a, 'tcx>,
+    fn is_sized_uncached(&'tcx self, tcx: TyCtxt<'a, 'tcx, 'tcx>,
+                         param_env: &ParameterEnvironment<'tcx>,
                          span: Span) -> bool {
         assert!(!self.needs_infer());
 
@@ -588,7 +588,7 @@ impl<'a, 'tcx> ty::TyS<'tcx> {
 
             TyEnum(..) | TyStruct(..) | TyProjection(..) | TyParam(..) |
             TyInfer(..) | TyError => None
-        }.unwrap_or_else(|| self.impls_bound(param_env, ty::BoundSized, span));
+        }.unwrap_or_else(|| self.impls_bound(tcx, param_env, ty::BoundSized, span));
 
         if !self.has_param_types() && !self.has_self_ty() {
             self.flags.set(self.flags.get() | if result {
diff --git a/src/librustc/util/ppaux.rs b/src/librustc/util/ppaux.rs
index 47d7e3a0a3c..cf00f790e53 100644
--- a/src/librustc/util/ppaux.rs
+++ b/src/librustc/util/ppaux.rs
@@ -557,7 +557,7 @@ impl<'tcx> fmt::Debug for ty::ClosureUpvar<'tcx> {
     }
 }
 
-impl<'a, 'tcx> fmt::Debug for ty::ParameterEnvironment<'a, 'tcx> {
+impl<'tcx> fmt::Debug for ty::ParameterEnvironment<'tcx> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         write!(f, "ParameterEnvironment(\
             free_substs={:?}, \