From 438652c2922ce3e9ddbf0ddfaeb37723b6fdb128 Mon Sep 17 00:00:00 2001
From: SparrowLii <liyuan179@huawei.com>
Date: Thu, 1 Sep 2022 16:34:05 +0800
Subject: [PATCH] avoid using `mk_attr_id` when decoding

---
 compiler/rustc_ast/src/ast.rs                |  4 ++--
 compiler/rustc_metadata/src/rmeta/decoder.rs | 11 +++++++++++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs
index fb521073a428d..15cafb52d11c8 100644
--- a/compiler/rustc_ast/src/ast.rs
+++ b/compiler/rustc_ast/src/ast.rs
@@ -2522,8 +2522,8 @@ impl<S: Encoder> Encodable<S> for AttrId {
 }
 
 impl<D: Decoder> Decodable<D> for AttrId {
-    fn decode(_: &mut D) -> AttrId {
-        crate::attr::mk_attr_id()
+    default fn decode(_: &mut D) -> AttrId {
+        panic!("cannot decode `AttrId` with `{}`", std::any::type_name::<D>());
     }
 }
 
diff --git a/compiler/rustc_metadata/src/rmeta/decoder.rs b/compiler/rustc_metadata/src/rmeta/decoder.rs
index d0e0aa91480c9..29309b45d37f5 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder.rs
@@ -4,6 +4,7 @@ use crate::creader::{CStore, CrateMetadataRef};
 use crate::rmeta::*;
 
 use rustc_ast as ast;
+use rustc_ast::ast::AttrId;
 use rustc_ast::ptr::P;
 use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::FxHashMap;
@@ -160,6 +161,7 @@ pub(super) struct DecodeContext<'a, 'tcx> {
     blob: &'a MetadataBlob,
     sess: Option<&'tcx Session>,
     tcx: Option<TyCtxt<'tcx>>,
+    next_id: u32,
 
     lazy_state: LazyState,
 
@@ -189,6 +191,7 @@ pub(super) trait Metadata<'a, 'tcx>: Copy {
             blob: self.blob(),
             sess: self.sess().or(tcx.map(|tcx| tcx.sess)),
             tcx,
+            next_id: 0,
             lazy_state: LazyState::NoNode,
             alloc_decoding_session: self
                 .cdata()
@@ -452,6 +455,14 @@ impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnIndex {
     }
 }
 
+impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for AttrId {
+    fn decode(d: &mut DecodeContext<'a, 'tcx>) -> AttrId {
+        let id = d.next_id;
+        d.next_id += 1;
+        AttrId::from_u32(id)
+    }
+}
+
 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for SyntaxContext {
     fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> SyntaxContext {
         let cdata = decoder.cdata();