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diff --git a/tests/ui/methods/rigid-alias-bound-is-not-inherent.rs b/tests/ui/methods/rigid-alias-bound-is-not-inherent.rs
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+//@ revisions: current next
+//@ ignore-compare-mode-next-solver (explicit revisions)
+//@[next] compile-flags: -Znext-solver
+
+// See the code below.
+//
+// We were using `DeepRejectCtxt` to ensure that `assemble_inherent_candidates_from_param`
+// did not rely on the param-env being eagerly normalized. Since aliases unify with all
+// types, this meant that a rigid param-env candidate like `<T as Deref>::Target: Trait1`
+// would be registered as a "WhereClauseCandidate", which is treated as inherent. Since
+// we evaluate these candidates for all self types in the deref chain, this candidate
+// would be satisfied for `<T as Deref>::Target`, meaning that it would be preferred over
+// an "extension" candidate like `<T as Deref>::Target: Trait2` even though it holds.
+// This is problematic, since it causes ambiguities to be broken somewhat arbitrarily.
+// And as a side-effect, it also caused our computation of "used" traits to be miscalculated
+// since inherent candidates don't count as an import usage.
+
+use std::ops::Deref;
+
+trait Trait1 {
+    fn method(&self) {
+        println!("1");
+    }
+}
+
+trait Trait2 {
+    fn method(&self) {
+        println!("2");
+    }
+}
+impl<T: Other + ?Sized> Trait2 for T {}
+
+trait Other {}
+
+fn foo<T>(x: T)
+where
+    T: Deref,
+    <T as Deref>::Target: Trait1 + Other,
+{
+    // Make sure that we don't prefer methods from where clauses for rigid aliases,
+    // just for params. We could revisit this behavior, but it would be a lang change.
+    x.method();
+    //~^ ERROR multiple applicable items in scope
+}
+
+fn main() {}