diff --git a/src/librustdoc/clean/inline.rs b/src/librustdoc/clean/inline.rs
index 89335821dd6..77f7f64b80b 100644
--- a/src/librustdoc/clean/inline.rs
+++ b/src/librustdoc/clean/inline.rs
@@ -244,7 +244,7 @@ fn build_enum(cx: &mut DocContext<'_>, did: DefId) -> clean::Enum {
     clean::Enum {
         generics: (cx.tcx.generics_of(did), predicates).clean(cx),
         variants_stripped: false,
-        variants: cx.tcx.adt_def(did).variants.clean(cx),
+        variants: cx.tcx.adt_def(did).variants.iter().map(|v| v.clean(cx)).collect(),
     }
 }
 
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index 756c8d37ab8..b5e15dd1820 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -16,7 +16,6 @@
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind, Res};
 use rustc_hir::def_id::{DefId, CRATE_DEF_INDEX, LOCAL_CRATE};
-use rustc_index::vec::{Idx, IndexVec};
 use rustc_infer::infer::region_constraints::{Constraint, RegionConstraintData};
 use rustc_middle::middle::resolve_lifetime as rl;
 use rustc_middle::ty::fold::TypeFolder;
@@ -62,12 +61,6 @@ fn clean(&self, cx: &mut DocContext<'_>) -> Vec<U> {
     }
 }
 
-impl<T: Clean<U>, U, V: Idx> Clean<IndexVec<V, U>> for IndexVec<V, T> {
-    fn clean(&self, cx: &mut DocContext<'_>) -> IndexVec<V, U> {
-        self.iter().map(|x| x.clean(cx)).collect()
-    }
-}
-
 impl<T: Clean<U>, U> Clean<U> for &T {
     fn clean(&self, cx: &mut DocContext<'_>) -> U {
         (**self).clean(cx)