diff --git a/compiler/rustc_target/src/abi/mod.rs b/compiler/rustc_target/src/abi/mod.rs
index a771369c807..d6b831c94e1 100644
--- a/compiler/rustc_target/src/abi/mod.rs
+++ b/compiler/rustc_target/src/abi/mod.rs
@@ -574,7 +574,7 @@ impl Align {
 }
 
 /// A pair of alignments, ABI-mandated and preferred.
-#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, Encodable, Decodable)]
+#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
 #[derive(HashStable_Generic)]
 pub struct AbiAndPrefAlign {
     pub abi: Align,
diff --git a/compiler/rustc_target/src/spec/mod.rs b/compiler/rustc_target/src/spec/mod.rs
index 6dd245b047c..b4e34a2aaf2 100644
--- a/compiler/rustc_target/src/spec/mod.rs
+++ b/compiler/rustc_target/src/spec/mod.rs
@@ -211,7 +211,7 @@ impl ToJson for PanicStrategy {
     }
 }
 
-#[derive(Clone, Copy, Debug, PartialEq, Hash, Encodable, Decodable)]
+#[derive(Clone, Copy, Debug, PartialEq, Hash)]
 pub enum RelroLevel {
     Full,
     Partial,
@@ -255,7 +255,7 @@ impl ToJson for RelroLevel {
     }
 }
 
-#[derive(Clone, Copy, Debug, PartialEq, Hash, Encodable, Decodable)]
+#[derive(Clone, Copy, Debug, PartialEq, Hash)]
 pub enum MergeFunctions {
     Disabled,
     Trampolines,