Rollup merge of #138678 - durin42:rmeta-stability, r=fmease

rustc_resolve: fix instability in lib.rmeta contents

rust-lang/rust@23032f31c91f2 accidentally introduced some nondeterminism in the ordering of lib.rmeta files, which we caught in our bazel-based builds only recently due to being further behind than normal. In my testing, this fixes the issue.

2 files changed, 6 insertions, 3 deletions

diff --git a/compiler/rustc_resolve/Cargo.toml b/compiler/rustc_resolve/Cargo.toml
index f4771f1af2c..9ea9c58cfd1 100644
--- a/compiler/rustc_resolve/Cargo.toml
+++ b/compiler/rustc_resolve/Cargo.toml
@@ -6,6 +6,7 @@ edition = "2024"
 [dependencies]
 # tidy-alphabetical-start
 bitflags = "2.4.1"
+itertools = "0.12"
 pulldown-cmark = { version = "0.11", features = ["html"], default-features = false }
 rustc_arena = { path = "../rustc_arena" }
 rustc_ast = { path = "../rustc_ast" }
diff --git a/compiler/rustc_resolve/src/rustdoc.rs b/compiler/rustc_resolve/src/rustdoc.rs
index 52aaab77ebe..a32fe699016 100644
--- a/compiler/rustc_resolve/src/rustdoc.rs
+++ b/compiler/rustc_resolve/src/rustdoc.rs
@@ -1,13 +1,15 @@
 use std::mem;
 use std::ops::Range;
 
+use itertools::Itertools;
 use pulldown_cmark::{
     BrokenLink, BrokenLinkCallback, CowStr, Event, LinkType, Options, Parser, Tag,
 };
 use rustc_ast as ast;
 use rustc_ast::attr::AttributeExt;
 use rustc_ast::util::comments::beautify_doc_string;
-use rustc_data_structures::fx::{FxHashSet, FxIndexMap};
+use rustc_data_structures::fx::FxIndexMap;
+use rustc_data_structures::unord::UnordSet;
 use rustc_middle::ty::TyCtxt;
 use rustc_span::def_id::DefId;
 use rustc_span::{DUMMY_SP, InnerSpan, Span, Symbol, kw, sym};
@@ -422,7 +424,7 @@ fn parse_links<'md>(doc: &'md str) -> Vec<Box<str>> {
     );
     let mut links = Vec::new();
 
-    let mut refids = FxHashSet::default();
+    let mut refids = UnordSet::default();
 
     while let Some(event) = event_iter.next() {
         match event {
@@ -454,7 +456,7 @@ fn parse_links<'md>(doc: &'md str) -> Vec<Box<str>> {
         }
     }
 
-    for (label, refdef) in event_iter.reference_definitions().iter() {
+    for (label, refdef) in event_iter.reference_definitions().iter().sorted_by_key(|x| x.0) {
         if !refids.contains(label) {
             links.push(preprocess_link(&refdef.dest));
         }