diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs
index 31e6750a678..3a81b93d157 100644
--- a/compiler/rustc_ast/src/ast.rs
+++ b/compiler/rustc_ast/src/ast.rs
@@ -241,15 +241,15 @@ impl AngleBracketedArg {
     }
 }
 
-impl Into<P<GenericArgs>> for AngleBracketedArgs {
-    fn into(self) -> P<GenericArgs> {
-        P(GenericArgs::AngleBracketed(self))
+impl From<AngleBracketedArgs> for P<GenericArgs> {
+    fn from(val: AngleBracketedArgs) -> Self {
+        P(GenericArgs::AngleBracketed(val))
     }
 }
 
-impl Into<P<GenericArgs>> for ParenthesizedArgs {
-    fn into(self) -> P<GenericArgs> {
-        P(GenericArgs::Parenthesized(self))
+impl From<ParenthesizedArgs> for P<GenericArgs> {
+    fn from(val: ParenthesizedArgs) -> Self {
+        P(GenericArgs::Parenthesized(val))
     }
 }
 
diff --git a/compiler/rustc_ast/src/ptr.rs b/compiler/rustc_ast/src/ptr.rs
index 97c714df8fd..dd923305cdf 100644
--- a/compiler/rustc_ast/src/ptr.rs
+++ b/compiler/rustc_ast/src/ptr.rs
@@ -158,9 +158,9 @@ impl<T> From<Vec<T>> for P<[T]> {
     }
 }
 
-impl<T> Into<Vec<T>> for P<[T]> {
-    fn into(self) -> Vec<T> {
-        self.into_vec()
+impl<T> From<P<[T]>> for Vec<T> {
+    fn from(val: P<[T]>) -> Self {
+        val.into_vec()
     }
 }
 
diff --git a/compiler/rustc_error_messages/src/lib.rs b/compiler/rustc_error_messages/src/lib.rs
index 74b6d63365a..a51c4140e17 100644
--- a/compiler/rustc_error_messages/src/lib.rs
+++ b/compiler/rustc_error_messages/src/lib.rs
@@ -357,9 +357,9 @@ impl From<Cow<'static, str>> for DiagMessage {
 /// subdiagnostic derive refers to typed identifiers that are `DiagMessage`s, so need to be
 /// able to convert between these, as much as they'll be converted back into `DiagMessage`
 /// using `with_subdiagnostic_message` eventually. Don't use this other than for the derive.
-impl Into<SubdiagMessage> for DiagMessage {
-    fn into(self) -> SubdiagMessage {
-        match self {
+impl From<DiagMessage> for SubdiagMessage {
+    fn from(val: DiagMessage) -> Self {
+        match val {
             DiagMessage::Str(s) => SubdiagMessage::Str(s),
             DiagMessage::Translated(s) => SubdiagMessage::Translated(s),
             DiagMessage::FluentIdentifier(id, None) => SubdiagMessage::FluentIdentifier(id),
diff --git a/compiler/rustc_errors/src/diagnostic.rs b/compiler/rustc_errors/src/diagnostic.rs
index 05b9cbfbc06..afce877547f 100644
--- a/compiler/rustc_errors/src/diagnostic.rs
+++ b/compiler/rustc_errors/src/diagnostic.rs
@@ -156,9 +156,9 @@ impl IntoDiagArg for DiagArgValue {
     }
 }
 
-impl Into<FluentValue<'static>> for DiagArgValue {
-    fn into(self) -> FluentValue<'static> {
-        match self {
+impl From<DiagArgValue> for FluentValue<'static> {
+    fn from(val: DiagArgValue) -> Self {
+        match val {
             DiagArgValue::Str(s) => From::from(s),
             DiagArgValue::Number(n) => From::from(n),
             DiagArgValue::StrListSepByAnd(l) => fluent_value_from_str_list_sep_by_and(l),
diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs
index 8cea269f298..5ea3bcef9ba 100644
--- a/compiler/rustc_hir/src/hir.rs
+++ b/compiler/rustc_hir/src/hir.rs
@@ -4072,33 +4072,33 @@ impl<'hir> OwnerNode<'hir> {
     }
 }
 
-impl<'hir> Into<OwnerNode<'hir>> for &'hir Item<'hir> {
-    fn into(self) -> OwnerNode<'hir> {
-        OwnerNode::Item(self)
+impl<'hir> From<&'hir Item<'hir>> for OwnerNode<'hir> {
+    fn from(val: &'hir Item<'hir>) -> Self {
+        OwnerNode::Item(val)
     }
 }
 
-impl<'hir> Into<OwnerNode<'hir>> for &'hir ForeignItem<'hir> {
-    fn into(self) -> OwnerNode<'hir> {
-        OwnerNode::ForeignItem(self)
+impl<'hir> From<&'hir ForeignItem<'hir>> for OwnerNode<'hir> {
+    fn from(val: &'hir ForeignItem<'hir>) -> Self {
+        OwnerNode::ForeignItem(val)
     }
 }
 
-impl<'hir> Into<OwnerNode<'hir>> for &'hir ImplItem<'hir> {
-    fn into(self) -> OwnerNode<'hir> {
-        OwnerNode::ImplItem(self)
+impl<'hir> From<&'hir ImplItem<'hir>> for OwnerNode<'hir> {
+    fn from(val: &'hir ImplItem<'hir>) -> Self {
+        OwnerNode::ImplItem(val)
     }
 }
 
-impl<'hir> Into<OwnerNode<'hir>> for &'hir TraitItem<'hir> {
-    fn into(self) -> OwnerNode<'hir> {
-        OwnerNode::TraitItem(self)
+impl<'hir> From<&'hir TraitItem<'hir>> for OwnerNode<'hir> {
+    fn from(val: &'hir TraitItem<'hir>) -> Self {
+        OwnerNode::TraitItem(val)
     }
 }
 
-impl<'hir> Into<Node<'hir>> for OwnerNode<'hir> {
-    fn into(self) -> Node<'hir> {
-        match self {
+impl<'hir> From<OwnerNode<'hir>> for Node<'hir> {
+    fn from(val: OwnerNode<'hir>) -> Self {
+        match val {
             OwnerNode::Item(n) => Node::Item(n),
             OwnerNode::ForeignItem(n) => Node::ForeignItem(n),
             OwnerNode::ImplItem(n) => Node::ImplItem(n),
diff --git a/compiler/rustc_metadata/src/rmeta/mod.rs b/compiler/rustc_metadata/src/rmeta/mod.rs
index 64a1c70dd2f..4fe8f73efd6 100644
--- a/compiler/rustc_metadata/src/rmeta/mod.rs
+++ b/compiler/rustc_metadata/src/rmeta/mod.rs
@@ -303,9 +303,9 @@ pub(crate) struct RawDefId {
     index: u32,
 }
 
-impl Into<RawDefId> for DefId {
-    fn into(self) -> RawDefId {
-        RawDefId { krate: self.krate.as_u32(), index: self.index.as_u32() }
+impl From<DefId> for RawDefId {
+    fn from(val: DefId) -> Self {
+        RawDefId { krate: val.krate.as_u32(), index: val.index.as_u32() }
     }
 }
 
diff --git a/compiler/rustc_middle/src/mir/interpret/error.rs b/compiler/rustc_middle/src/mir/interpret/error.rs
index 37328470aa7..8c085fa310a 100644
--- a/compiler/rustc_middle/src/mir/interpret/error.rs
+++ b/compiler/rustc_middle/src/mir/interpret/error.rs
@@ -88,10 +88,10 @@ impl ReportedErrorInfo {
     }
 }
 
-impl Into<ErrorGuaranteed> for ReportedErrorInfo {
+impl From<ReportedErrorInfo> for ErrorGuaranteed {
     #[inline]
-    fn into(self) -> ErrorGuaranteed {
-        self.error
+    fn from(val: ReportedErrorInfo) -> Self {
+        val.error
     }
 }
 
diff --git a/compiler/rustc_middle/src/ty/adt.rs b/compiler/rustc_middle/src/ty/adt.rs
index 8f4137cc011..e28fcc555dc 100644
--- a/compiler/rustc_middle/src/ty/adt.rs
+++ b/compiler/rustc_middle/src/ty/adt.rs
@@ -249,9 +249,9 @@ pub enum AdtKind {
     Enum,
 }
 
-impl Into<DataTypeKind> for AdtKind {
-    fn into(self) -> DataTypeKind {
-        match self {
+impl From<AdtKind> for DataTypeKind {
+    fn from(val: AdtKind) -> Self {
+        match val {
             AdtKind::Struct => DataTypeKind::Struct,
             AdtKind::Union => DataTypeKind::Union,
             AdtKind::Enum => DataTypeKind::Enum,
diff --git a/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs b/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs
index 2dcf3760d2f..68a53381230 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs
@@ -45,12 +45,12 @@ pub enum TypeAnnotationNeeded {
     E0284,
 }
 
-impl Into<ErrCode> for TypeAnnotationNeeded {
-    fn into(self) -> ErrCode {
-        match self {
-            Self::E0282 => E0282,
-            Self::E0283 => E0283,
-            Self::E0284 => E0284,
+impl From<TypeAnnotationNeeded> for ErrCode {
+    fn from(val: TypeAnnotationNeeded) -> Self {
+        match val {
+            TypeAnnotationNeeded::E0282 => E0282,
+            TypeAnnotationNeeded::E0283 => E0283,
+            TypeAnnotationNeeded::E0284 => E0284,
         }
     }
 }