review comments

compiler/rustc_trait_selection/src/traits/codegen.rs

@@ -121,7 +121,10 @@ fn drain_fulfillment_cx_or_panic<T>(
     // contains unbound type parameters. It could be a slight
     // optimization to stop iterating early.
     if let Err(errors) = fulfill_cx.select_all_or_error(infcx) {
-        bug!("Encountered errors `{:?}` resolving bounds after type-checking", errors);
+        infcx.tcx.sess.delay_span_bug(
+            rustc_span::DUMMY_SP,
+            &format!("Encountered errors `{:?}` resolving bounds after type-checking", errors),
+        );
     }
 
     let result = infcx.resolve_vars_if_possible(result);

compiler/rustc_trait_selection/src/traits/select/mod.rs

@@ -2031,19 +2031,12 @@ fn impl_or_trait_obligations(
                 &predicate.subst(tcx, substs),
                 &mut obligations,
             );
-            if predicate.references_error() {
-                self.tcx().sess.delay_span_bug(
-                    cause.span,
-                    &format!("impl_or_trait_obligation with errors: {:?}", predicate),
-                );
-            } else {
-                obligations.push(Obligation {
-                    cause: cause.clone(),
-                    recursion_depth,
-                    param_env,
-                    predicate,
-                });
-            }
+            obligations.push(Obligation {
+                cause: cause.clone(),
+                recursion_depth,
+                param_env,
+                predicate,
+            });
         }
 
         // We are performing deduplication here to avoid exponential blowups