diff --git a/compiler/rustc_middle/src/query/keys.rs b/compiler/rustc_middle/src/query/keys.rs
index b1f83796862..11376345052 100644
--- a/compiler/rustc_middle/src/query/keys.rs
+++ b/compiler/rustc_middle/src/query/keys.rs
@@ -12,7 +12,6 @@
 use rustc_query_system::query::{DefaultCacheSelector, SingleCacheSelector, VecCacheSelector};
 use rustc_span::symbol::{Ident, Symbol};
 use rustc_span::{Span, DUMMY_SP};
-use rustc_target::abi::FieldIdx;
 
 /// Placeholder for `CrateNum`'s "local" counterpart
 #[derive(Copy, Clone, Debug)]
@@ -360,30 +359,6 @@ fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
     }
 }
 
-impl<'tcx> Key for (ty::Const<'tcx>, FieldIdx) {
-    type CacheSelector = DefaultCacheSelector<Self>;
-
-    fn default_span(&self, _: TyCtxt<'_>) -> Span {
-        DUMMY_SP
-    }
-}
-
-impl<'tcx> Key for (mir::ConstValue<'tcx>, Ty<'tcx>) {
-    type CacheSelector = DefaultCacheSelector<Self>;
-
-    fn default_span(&self, _: TyCtxt<'_>) -> Span {
-        DUMMY_SP
-    }
-}
-
-impl<'tcx> Key for mir::ConstAlloc<'tcx> {
-    type CacheSelector = DefaultCacheSelector<Self>;
-
-    fn default_span(&self, _: TyCtxt<'_>) -> Span {
-        DUMMY_SP
-    }
-}
-
 impl<'tcx> Key for ty::PolyTraitRef<'tcx> {
     type CacheSelector = DefaultCacheSelector<Self>;
 
@@ -416,14 +391,6 @@ fn default_span(&self, _: TyCtxt<'_>) -> Span {
     }
 }
 
-impl<'tcx> Key for mir::Const<'tcx> {
-    type CacheSelector = DefaultCacheSelector<Self>;
-
-    fn default_span(&self, _: TyCtxt<'_>) -> Span {
-        DUMMY_SP
-    }
-}
-
 impl<'tcx> Key for ty::Const<'tcx> {
     type CacheSelector = DefaultCacheSelector<Self>;