fix: skip implied bounds if unconstrained lifetime exists

1 files changed, 10 insertions, 1 deletions

diff --git a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs
index cff3d277a78..64be4a55708 100644
--- a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs
+++ b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs
@@ -55,7 +55,16 @@ impl<'a, 'tcx: 'a> InferCtxtExt<'a, 'tcx> for InferCtxt<'tcx> {
     ) -> Vec<OutlivesBound<'tcx>> {
         let ty = self.resolve_vars_if_possible(ty);
         let ty = OpportunisticRegionResolver::new(self).fold_ty(ty);
-        assert!(!ty.needs_infer());
+
+        // We must avoid processing constrained lifetime variables in implied
+        // bounds. See #110161 for context.
+        if ty.needs_infer() {
+            self.tcx.sess.delay_span_bug(
+                self.tcx.source_span_untracked(body_id),
+                "skipped implied_outlives_bounds due to unconstrained lifetimes",
+            );
+            return vec![];
+        }
 
         let span = self.tcx.def_span(body_id);
         let result = param_env