From a4b0d2419a1c0c400ba2630992da086606dfe426 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?D=C3=A1niel=20Buga?= <bugadani@gmail.com>
Date: Sun, 11 Oct 2020 11:30:25 +0200
Subject: [PATCH] Remove canonicalize_hr_query_hack

---
 .../src/infer/canonical/canonicalizer.rs      | 52 -------------------
 .../src/traits/query/normalize.rs             |  5 +-
 .../src/traits/query/type_op/mod.rs           |  7 +--
 3 files changed, 3 insertions(+), 61 deletions(-)

diff --git a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
index 871fc4fafe269..e151170b3a3fe 100644
--- a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
+++ b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
@@ -107,38 +107,6 @@ impl<'cx, 'tcx> InferCtxt<'cx, 'tcx> {
             &mut query_state,
         )
     }
-
-    /// A hacky variant of `canonicalize_query` that does not
-    /// canonicalize `'static`. Unfortunately, the existing leak
-    /// check treats `'static` differently in some cases (see also
-    /// #33684), so if we are performing an operation that may need to
-    /// prove "leak-check" related things, we leave `'static`
-    /// alone.
-    ///
-    /// `'static` is also special cased when winnowing candidates when
-    /// selecting implementation candidates, so we also have to leave `'static`
-    /// alone for queries that do selection.
-    //
-    // FIXME(#48536): once the above issues are resolved, we can remove this
-    // and just use `canonicalize_query`.
-    pub fn canonicalize_hr_query_hack<V>(
-        &self,
-        value: &V,
-        query_state: &mut OriginalQueryValues<'tcx>,
-    ) -> Canonicalized<'tcx, V>
-    where
-        V: TypeFoldable<'tcx>,
-    {
-        self.tcx.sess.perf_stats.queries_canonicalized.fetch_add(1, Ordering::Relaxed);
-
-        Canonicalizer::canonicalize(
-            value,
-            Some(self),
-            self.tcx,
-            &CanonicalizeFreeRegionsOtherThanStatic,
-            query_state,
-        )
-    }
 }
 
 /// Controls how we canonicalize "free regions" that are not inference
@@ -254,26 +222,6 @@ impl CanonicalizeRegionMode for CanonicalizeAllFreeRegions {
     }
 }
 
-struct CanonicalizeFreeRegionsOtherThanStatic;
-
-impl CanonicalizeRegionMode for CanonicalizeFreeRegionsOtherThanStatic {
-    fn canonicalize_free_region(
-        &self,
-        canonicalizer: &mut Canonicalizer<'_, 'tcx>,
-        r: ty::Region<'tcx>,
-    ) -> ty::Region<'tcx> {
-        if let ty::ReStatic = r {
-            r
-        } else {
-            canonicalizer.canonical_var_for_region_in_root_universe(r)
-        }
-    }
-
-    fn any(&self) -> bool {
-        true
-    }
-}
-
 struct Canonicalizer<'cx, 'tcx> {
     infcx: Option<&'cx InferCtxt<'cx, 'tcx>>,
     tcx: TyCtxt<'tcx>,
diff --git a/compiler/rustc_trait_selection/src/traits/query/normalize.rs b/compiler/rustc_trait_selection/src/traits/query/normalize.rs
index bdbf45f78a23b..74c8eb83bfb57 100644
--- a/compiler/rustc_trait_selection/src/traits/query/normalize.rs
+++ b/compiler/rustc_trait_selection/src/traits/query/normalize.rs
@@ -163,9 +163,8 @@ impl<'cx, 'tcx> TypeFolder<'tcx> for QueryNormalizer<'cx, 'tcx> {
                 let mut orig_values = OriginalQueryValues::default();
                 // HACK(matthewjasper) `'static` is special-cased in selection,
                 // so we cannot canonicalize it.
-                let c_data = self
-                    .infcx
-                    .canonicalize_hr_query_hack(&self.param_env.and(*data), &mut orig_values);
+                let c_data =
+                    self.infcx.canonicalize_query(&self.param_env.and(*data), &mut orig_values);
                 debug!("QueryNormalizer: c_data = {:#?}", c_data);
                 debug!("QueryNormalizer: orig_values = {:#?}", orig_values);
                 match tcx.normalize_projection_ty(c_data) {
diff --git a/compiler/rustc_trait_selection/src/traits/query/type_op/mod.rs b/compiler/rustc_trait_selection/src/traits/query/type_op/mod.rs
index ed6c6d0cc0a98..057ef4f29b236 100644
--- a/compiler/rustc_trait_selection/src/traits/query/type_op/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/query/type_op/mod.rs
@@ -76,13 +76,8 @@ pub trait QueryTypeOp<'tcx>: fmt::Debug + Sized + TypeFoldable<'tcx> + 'tcx {
             return Ok(result);
         }
 
-        // FIXME(#33684) -- We need to use
-        // `canonicalize_hr_query_hack` here because of things
-        // like the subtype query, which go awry around
-        // `'static` otherwise.
         let mut canonical_var_values = OriginalQueryValues::default();
-        let canonical_self =
-            infcx.canonicalize_hr_query_hack(&query_key, &mut canonical_var_values);
+        let canonical_self = infcx.canonicalize_query(&query_key, &mut canonical_var_values);
         let canonical_result = Self::perform_query(infcx.tcx, canonical_self)?;
 
         let param_env = query_key.param_env;