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Author: cjgillot

compiler/rustc_typeck/src/astconv/mod.rs

@@ -205,6 +205,11 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         def: Option<&ty::GenericParamDef>,
     ) -> ty::Region<'tcx> {
         let tcx = self.tcx();
+        if let hir::LifetimeName::ImplicitObjectLifetimeDefault = lifetime.name {
+            panic!(
+                "ImplicitObjectLifetimeDefault should be handled separately from ast_region_to_region."
+            );
+        }
 
         let r = if let Some(rl) = tcx.named_region(lifetime.hir_id) {
             self.ast_region_to_region_inner(rl)

compiler/rustc_typeck/src/collect.rs

@@ -1349,6 +1349,9 @@ fn has_late_bound_regions<'tcx>(tcx: TyCtxt<'tcx>, node: Node<'tcx>) -> Option<S
                 return;
             }
             if let hir::LifetimeName::ImplicitObjectLifetimeDefault = lt.name {
+                // The lifetime this resolves must already have been encountered
+                // by the visitor, or be `'static`.  In both cases, we have nothing
+                // to do.
                 return;
             }