Remove two unnecessary span_delayed_bug calls.

In both cases, the existing code calls a function that returns
`Result<_, ErrorGuaranteed>`, and then calls `span_delayed_bug`
pointlessly in the `Err` case. This commits removes those calls.

Author: nnethercote

compiler/rustc_borrowck/src/type_check/free_region_relations.rs

@@ -311,14 +311,14 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> {
         // Add implied bounds from impl header.
         if matches!(tcx.def_kind(defining_ty_def_id), DefKind::AssocFn | DefKind::AssocConst) {
             for &(ty, _) in tcx.assumed_wf_types(tcx.local_parent(defining_ty_def_id)) {
-                let Ok(TypeOpOutput { output: norm_ty, constraints: c, .. }) = self
+                let result: Result<_, ErrorGuaranteed> = self
                     .param_env
                     .and(type_op::normalize::Normalize::new(ty))
-                    .fully_perform(self.infcx, span)
-                else {
-                    tcx.dcx().span_delayed_bug(span, format!("failed to normalize {ty:?}"));
+                    .fully_perform(self.infcx, span);
+                let Ok(TypeOpOutput { output: norm_ty, constraints: c, .. }) = result else {
                     continue;
                 };
+
                 constraints.extend(c);
 
                 // We currently add implied bounds from the normalized ty only.

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -1054,7 +1054,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         });
 
         let param_env = self.param_env;
-        let result = self.fully_perform_op(
+        let _: Result<_, ErrorGuaranteed> = self.fully_perform_op(
             Locations::All(self.body.span),
             ConstraintCategory::OpaqueType,
             CustomTypeOp::new(
@@ -1087,13 +1087,6 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                 "register pre-defined opaques",
             ),
         );
-
-        if result.is_err() {
-            self.infcx.dcx().span_delayed_bug(
-                self.body.span,
-                "failed re-defining predefined opaques in mir typeck",
-            );
-        }
     }
 
     fn body(&self) -> &Body<'tcx> {