1 files changed, 21 insertions, 11 deletions
diff --git a/compiler/rustc_trait_selection/src/traits/query/normalize.rs b/compiler/rustc_trait_selection/src/traits/query/normalize.rs
index 58e4597b7..7ad532d8a 100644
--- a/compiler/rustc_trait_selection/src/traits/query/normalize.rs
+++ b/compiler/rustc_trait_selection/src/traits/query/normalize.rs
@@ -7,7 +7,7 @@ use crate::infer::canonical::OriginalQueryValues;
 use crate::infer::{InferCtxt, InferOk};
 use crate::traits::error_reporting::TypeErrCtxtExt;
 use crate::traits::project::{needs_normalization, BoundVarReplacer, PlaceholderReplacer};
-use crate::traits::{Obligation, ObligationCause, PredicateObligation, Reveal};
+use crate::traits::{ObligationCause, PredicateObligation, Reveal};
 use rustc_data_structures::sso::SsoHashMap;
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_infer::traits::Normalized;
@@ -22,13 +22,20 @@ use super::NoSolution;
 
 pub use rustc_middle::traits::query::NormalizationResult;
 
-pub trait AtExt<'tcx> {
-    fn normalize<T>(&self, value: T) -> Result<Normalized<'tcx, T>, NoSolution>
+pub trait QueryNormalizeExt<'tcx> {
+    /// Normalize a value using the `QueryNormalizer`.
+    ///
+    /// This normalization should *only* be used when the projection does not
+    /// have possible ambiguity or may not be well-formed.
+    ///
+    /// After codegen, when lifetimes do not matter, it is preferable to instead
+    /// use [`TyCtxt::normalize_erasing_regions`], which wraps this procedure.
+    fn query_normalize<T>(&self, value: T) -> Result<Normalized<'tcx, T>, NoSolution>
     where
         T: TypeFoldable<'tcx>;
 }
 
-impl<'cx, 'tcx> AtExt<'tcx> for At<'cx, 'tcx> {
+impl<'cx, 'tcx> QueryNormalizeExt<'tcx> for At<'cx, 'tcx> {
     /// Normalize `value` in the context of the inference context,
     /// yielding a resulting type, or an error if `value` cannot be
     /// normalized. If you don't care about regions, you should prefer
@@ -42,7 +49,7 @@ impl<'cx, 'tcx> AtExt<'tcx> for At<'cx, 'tcx> {
     /// normalizing, but for now should be used only when we actually
     /// know that normalization will succeed, since error reporting
     /// and other details are still "under development".
-    fn normalize<T>(&self, value: T) -> Result<Normalized<'tcx, T>, NoSolution>
+    fn query_normalize<T>(&self, value: T) -> Result<Normalized<'tcx, T>, NoSolution>
     where
         T: TypeFoldable<'tcx>,
     {
@@ -207,13 +214,12 @@ impl<'cx, 'tcx> FallibleTypeFolder<'tcx> for QueryNormalizer<'cx, 'tcx> {
                         let substs = substs.try_fold_with(self)?;
                         let recursion_limit = self.tcx().recursion_limit();
                         if !recursion_limit.value_within_limit(self.anon_depth) {
-                            let obligation = Obligation::with_depth(
-                                self.cause.clone(),
-                                recursion_limit.0,
-                                self.param_env,
-                                ty,
+                            self.infcx.err_ctxt().report_overflow_error(
+                                &ty,
+                                self.cause.span,
+                                true,
+                                |_| {},
                             );
-                            self.infcx.err_ctxt().report_overflow_error(&obligation, true);
                         }
 
                         let generic_ty = self.tcx().bound_type_of(def_id);
@@ -353,6 +359,10 @@ impl<'cx, 'tcx> FallibleTypeFolder<'tcx> for QueryNormalizer<'cx, 'tcx> {
         &mut self,
         constant: ty::Const<'tcx>,
     ) -> Result<ty::Const<'tcx>, Self::Error> {
+        if !needs_normalization(&constant, self.param_env.reveal()) {
+            return Ok(constant);
+        }
+
         let constant = constant.try_super_fold_with(self)?;
         debug!(?constant, ?self.param_env);
         Ok(crate::traits::project::with_replaced_escaping_bound_vars(