diff --git a/compiler/rustc_metadata/src/lib.rs b/compiler/rustc_metadata/src/lib.rs
index 10f2087d1e6..f206dba6cf4 100644
--- a/compiler/rustc_metadata/src/lib.rs
+++ b/compiler/rustc_metadata/src/lib.rs
@@ -1,6 +1,5 @@
 // tidy-alphabetical-start
 #![allow(internal_features)]
-#![allow(rustc::potential_query_instability)]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![doc(rust_logo)]
 #![feature(control_flow_enum)]
diff --git a/compiler/rustc_metadata/src/locator.rs b/compiler/rustc_metadata/src/locator.rs
index 089ac060ba8..99c673b021a 100644
--- a/compiler/rustc_metadata/src/locator.rs
+++ b/compiler/rustc_metadata/src/locator.rs
@@ -218,7 +218,7 @@ use std::ops::Deref;
 use std::path::{Path, PathBuf};
 use std::{cmp, fmt};
 
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::fx::{FxHashSet, FxIndexMap};
 use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::owned_slice::slice_owned;
 use rustc_data_structures::svh::Svh;
@@ -385,7 +385,7 @@ impl<'a> CrateLocator<'a> {
         let dylib_suffix = &self.target.dll_suffix;
         let staticlib_suffix = &self.target.staticlib_suffix;
 
-        let mut candidates: FxHashMap<_, (FxHashMap<_, _>, FxHashMap<_, _>, FxHashMap<_, _>)> =
+        let mut candidates: FxIndexMap<_, (FxIndexMap<_, _>, FxIndexMap<_, _>, FxIndexMap<_, _>)> =
             Default::default();
 
         // First, find all possible candidate rlibs and dylibs purely based on
@@ -460,7 +460,7 @@ impl<'a> CrateLocator<'a> {
         // A Library candidate is created if the metadata for the set of
         // libraries corresponds to the crate id and hash criteria that this
         // search is being performed for.
-        let mut libraries = FxHashMap::default();
+        let mut libraries = FxIndexMap::default();
         for (_hash, (rlibs, rmetas, dylibs)) in candidates {
             if let Some((svh, lib)) = self.extract_lib(rlibs, rmetas, dylibs)? {
                 libraries.insert(svh, lib);
@@ -494,9 +494,9 @@ impl<'a> CrateLocator<'a> {
 
     fn extract_lib(
         &mut self,
-        rlibs: FxHashMap<PathBuf, PathKind>,
-        rmetas: FxHashMap<PathBuf, PathKind>,
-        dylibs: FxHashMap<PathBuf, PathKind>,
+        rlibs: FxIndexMap<PathBuf, PathKind>,
+        rmetas: FxIndexMap<PathBuf, PathKind>,
+        dylibs: FxIndexMap<PathBuf, PathKind>,
     ) -> Result<Option<(Svh, Library)>, CrateError> {
         let mut slot = None;
         // Order here matters, rmeta should come first. See comment in
@@ -534,7 +534,7 @@ impl<'a> CrateLocator<'a> {
     // The `PathBuf` in `slot` will only be used for diagnostic purposes.
     fn extract_one(
         &mut self,
-        m: FxHashMap<PathBuf, PathKind>,
+        m: FxIndexMap<PathBuf, PathKind>,
         flavor: CrateFlavor,
         slot: &mut Option<(Svh, MetadataBlob, PathBuf)>,
     ) -> Result<Option<(PathBuf, PathKind)>, CrateError> {
@@ -702,9 +702,9 @@ impl<'a> CrateLocator<'a> {
         // First, filter out all libraries that look suspicious. We only accept
         // files which actually exist that have the correct naming scheme for
         // rlibs/dylibs.
-        let mut rlibs = FxHashMap::default();
-        let mut rmetas = FxHashMap::default();
-        let mut dylibs = FxHashMap::default();
+        let mut rlibs = FxIndexMap::default();
+        let mut rmetas = FxIndexMap::default();
+        let mut dylibs = FxIndexMap::default();
         for loc in &self.exact_paths {
             if !loc.canonicalized().exists() {
                 return Err(CrateError::ExternLocationNotExist(
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
index c4a28845085..f32daee7c44 100644
--- a/compiler/rustc_middle/src/ty/mod.rs
+++ b/compiler/rustc_middle/src/ty/mod.rs
@@ -187,8 +187,8 @@ pub struct ResolverGlobalCtxt {
     /// Mapping from ident span to path span for paths that don't exist as written, but that
     /// exist under `std`. For example, wrote `str::from_utf8` instead of `std::str::from_utf8`.
     pub confused_type_with_std_module: FxIndexMap<Span, Span>,
-    pub doc_link_resolutions: FxHashMap<LocalDefId, DocLinkResMap>,
-    pub doc_link_traits_in_scope: FxHashMap<LocalDefId, Vec<DefId>>,
+    pub doc_link_resolutions: FxIndexMap<LocalDefId, DocLinkResMap>,
+    pub doc_link_traits_in_scope: FxIndexMap<LocalDefId, Vec<DefId>>,
     pub all_macro_rules: FxHashMap<Symbol, Res<ast::NodeId>>,
     pub stripped_cfg_items: Steal<Vec<StrippedCfgItem>>,
 }
diff --git a/compiler/rustc_resolve/src/lib.rs b/compiler/rustc_resolve/src/lib.rs
index 0c1a0038f9c..fcbbb523cfc 100644
--- a/compiler/rustc_resolve/src/lib.rs
+++ b/compiler/rustc_resolve/src/lib.rs
@@ -1196,8 +1196,8 @@ pub struct Resolver<'ra, 'tcx> {
     stripped_cfg_items: Vec<StrippedCfgItem<NodeId>>,
 
     effective_visibilities: EffectiveVisibilities,
-    doc_link_resolutions: FxHashMap<LocalDefId, DocLinkResMap>,
-    doc_link_traits_in_scope: FxHashMap<LocalDefId, Vec<DefId>>,
+    doc_link_resolutions: FxIndexMap<LocalDefId, DocLinkResMap>,
+    doc_link_traits_in_scope: FxIndexMap<LocalDefId, Vec<DefId>>,
     all_macro_rules: FxHashMap<Symbol, Res>,
 
     /// Invocation ids of all glob delegations.