Remove extern crate bitflags from a couple of crates.

compiler/rustc_middle/src/lib.rs

@@ -65,8 +65,6 @@
 #![allow(rustc::diagnostic_outside_of_impl)]
 #![allow(rustc::untranslatable_diagnostic)]
 
-#[macro_use]
-extern crate bitflags;
 #[macro_use]
 extern crate tracing;
 #[macro_use]

compiler/rustc_middle/src/middle/codegen_fn_attrs.rs

@@ -49,7 +49,7 @@ pub struct CodegenFnAttrs {
 
 #[derive(Clone, Copy, PartialEq, Eq, TyEncodable, TyDecodable, HashStable)]
 pub struct CodegenFnAttrFlags(u32);
-bitflags! {
+bitflags::bitflags! {
     impl CodegenFnAttrFlags: u32 {
         /// `#[cold]`: a hint to LLVM that this function, when called, is never on
         /// the hot path.

compiler/rustc_middle/src/ty/adt.rs

@@ -27,7 +27,7 @@ use super::{Destructor, FieldDef, GenericPredicates, Ty, TyCtxt, VariantDef, Var
 
 #[derive(Clone, Copy, PartialEq, Eq, Hash, HashStable, TyEncodable, TyDecodable)]
 pub struct AdtFlags(u16);
-bitflags! {
+bitflags::bitflags! {
     impl AdtFlags: u16 {
         const NO_ADT_FLAGS        = 0;
         /// Indicates whether the ADT is an enum.

compiler/rustc_middle/src/ty/mod.rs

@@ -1224,7 +1224,7 @@ pub struct Destructor {
 
 #[derive(Clone, Copy, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)]
 pub struct VariantFlags(u8);
-bitflags! {
+bitflags::bitflags! {
     impl VariantFlags: u8 {
         const NO_VARIANT_FLAGS        = 0;
         /// Indicates whether the field list of this variant is `#[non_exhaustive]`.

compiler/rustc_type_ir/src/flags.rs

@@ -1,4 +1,4 @@
-bitflags! {
+bitflags::bitflags! {
     /// Flags that we track on types. These flags are propagated upwards
     /// through the type during type construction, so that we can quickly check
     /// whether the type has various kinds of types in it without recursing

compiler/rustc_type_ir/src/lib.rs

@@ -8,9 +8,6 @@
 #[cfg(feature = "nightly")]
 extern crate self as rustc_type_ir;
 
-#[macro_use]
-extern crate bitflags;
-
 #[cfg(feature = "nightly")]
 use rustc_data_structures::sync::Lrc;
 #[cfg(feature = "nightly")]