Don't elaborate effects predicates into bounds list unless we're actually collecting implied bounds, not super bounds

compiler/rustc_hir_analysis/src/bounds.rs

@@ -9,6 +9,8 @@ use rustc_middle::ty::{self, Ty, TyCtxt, Upcast};
 use rustc_span::def_id::DefId;
 use rustc_span::Span;
 
+use crate::hir_ty_lowering::OnlySelfBounds;
+
 /// Collects together a list of type bounds. These lists of bounds occur in many places
 /// in Rust's syntax:
 ///
@@ -50,6 +52,7 @@ impl<'tcx> Bounds<'tcx> {
         span: Span,
         polarity: ty::PredicatePolarity,
         constness: ty::BoundConstness,
+        only_self_bounds: OnlySelfBounds,
     ) {
         let clause = (
             bound_trait_ref
@@ -66,7 +69,10 @@ impl<'tcx> Bounds<'tcx> {
             self.clauses.push(clause);
         }
 
-        if !tcx.features().effects {
+        // FIXME(effects): Lift this out of `push_trait_bound`, and move it somewhere else.
+        // Perhaps moving this into `lower_poly_trait_ref`, just like we lower associated
+        // type bounds.
+        if !tcx.features().effects || only_self_bounds.0 {
             return;
         }
         // For `T: ~const Tr` or `T: const Tr`, we need to add an additional bound on the

compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs

@@ -719,6 +719,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             span,
             polarity,
             constness,
+            only_self_bounds,
         );
 
         let mut dup_constraints = FxIndexMap::default();