diff --git a/compiler/rustc_public/src/crate_def.rs b/compiler/rustc_public/src/crate_def.rs
index e534004af4d3..7773abdcb4d2 100644
--- a/compiler/rustc_public/src/crate_def.rs
+++ b/compiler/rustc_public/src/crate_def.rs
@@ -2,7 +2,7 @@
 //! such as, a function, a trait, an enum, and any other definitions.
 
 use crate::ty::{GenericArgs, Span, Ty, index_impl};
-use crate::{AssocItems, Crate, Symbol, ThreadLocalIndex, with};
+use crate::{Crate, Symbol, ThreadLocalIndex, with};
 
 /// A unique identification number for each item accessible for the current compilation unit.
 #[derive(Clone, Copy, PartialEq, Eq, Hash)]
@@ -111,14 +111,6 @@ fn ty_with_args(&self, args: &GenericArgs) -> Ty {
     }
 }
 
-/// A trait for retrieving all items from a definition within a crate.
-pub trait CrateDefItems: CrateDef {
-    /// Retrieve all associated items from a definition.
-    fn associated_items(&self) -> AssocItems {
-        with(|cx| cx.associated_items(self.def_id()))
-    }
-}
-
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub struct Attribute {
     value: String,
@@ -174,9 +166,3 @@ fn def_id(&self) -> DefId {
         impl CrateDefType for $name {}
     };
 }
-
-macro_rules! impl_crate_def_items {
-    ( $name:ident $(;)? ) => {
-        impl CrateDefItems for $name {}
-    };
-}
diff --git a/compiler/rustc_public/src/lib.rs b/compiler/rustc_public/src/lib.rs
index a73aab002753..e1e02e282bf2 100644
--- a/compiler/rustc_public/src/lib.rs
+++ b/compiler/rustc_public/src/lib.rs
@@ -30,7 +30,7 @@
 use serde::Serialize;
 
 use crate::compiler_interface::with;
-pub use crate::crate_def::{CrateDef, CrateDefItems, CrateDefType, DefId};
+pub use crate::crate_def::{CrateDef, CrateDefType, DefId};
 pub use crate::error::*;
 use crate::mir::mono::StaticDef;
 use crate::mir::{Body, Mutability};
diff --git a/compiler/rustc_public/src/ty.rs b/compiler/rustc_public/src/ty.rs
index 5d8e833ac63b..4800bf1e84e9 100644
--- a/compiler/rustc_public/src/ty.rs
+++ b/compiler/rustc_public/src/ty.rs
@@ -7,11 +7,11 @@
 use super::mir::{Body, Mutability, Safety};
 use super::{DefId, Error, Symbol, with};
 use crate::abi::{FnAbi, Layout};
-use crate::crate_def::{CrateDef, CrateDefItems, CrateDefType};
+use crate::crate_def::{CrateDef, CrateDefType};
 use crate::mir::alloc::{AllocId, read_target_int, read_target_uint};
 use crate::mir::mono::StaticDef;
 use crate::target::MachineInfo;
-use crate::{Filename, IndexedVal, Opaque, ThreadLocalIndex};
+use crate::{AssocItems, Filename, IndexedVal, Opaque, ThreadLocalIndex};
 
 #[derive(Copy, Clone, Eq, PartialEq, Hash)]
 pub struct Ty(usize, ThreadLocalIndex);
@@ -943,14 +943,14 @@ pub fn is_union(&self) -> bool {
     pub TraitDef;
 }
 
-impl_crate_def_items! {
-    TraitDef;
-}
-
 impl TraitDef {
     pub fn declaration(trait_def: &TraitDef) -> TraitDecl {
         with(|cx| cx.trait_decl(trait_def))
     }
+
+    pub fn associated_items(&self) -> AssocItems {
+        with(|cx| cx.associated_items(self.def_id()))
+    }
 }
 
 crate_def! {
@@ -969,15 +969,15 @@ pub fn declaration(trait_def: &TraitDef) -> TraitDecl {
     pub ImplDef;
 }
 
-impl_crate_def_items! {
-    ImplDef;
-}
-
 impl ImplDef {
     /// Retrieve information about this implementation.
     pub fn trait_impl(&self) -> ImplTrait {
         with(|cx| cx.trait_impl(self))
     }
+
+    pub fn associated_items(&self) -> AssocItems {
+        with(|cx| cx.associated_items(self.def_id()))
+    }
 }
 
 crate_def! {