review comments

compiler/rustc_hir_analysis/src/collect/type_of.rs

@@ -928,7 +928,7 @@ fn infer_placeholder_type<'a>(
 
     // Typeck doesn't expect erased regions to be returned from `type_of`.
     tcx.fold_regions(ty, |r, _| match *r {
-        ty::ReErased | ty::ReError => tcx.lifetimes.re_static,
+        ty::ReErased => tcx.lifetimes.re_static,
         _ => r,
     })
 }

compiler/rustc_infer/src/infer/lexical_region_resolve/mod.rs

@@ -211,11 +211,13 @@ impl<'cx, 'tcx> LexicalResolver<'cx, 'tcx> {
                 );
             }
 
-            ReStatic | ReError => {
+            ReStatic => {
                 // nothing lives longer than `'static`
                 Ok(self.tcx().lifetimes.re_static)
             }
 
+            ReError => Ok(self.tcx().lifetimes.re_error),
+
             ReEarlyBound(_) | ReFree(_) => {
                 // All empty regions are less than early-bound, free,
                 // and scope regions.