Make iteration order of named_variable_map, late_bound_vars_map, and resolve_bound_vars queries stable

Author: michaelwoerister

compiler/rustc_middle/src/middle/resolve_bound_vars.rs

@@ -2,7 +2,7 @@
 
 use crate::ty;
 
-use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::fx::FxIndexMap;
 use rustc_errors::ErrorGuaranteed;
 use rustc_hir::def_id::DefId;
 use rustc_hir::{ItemLocalId, OwnerId};
@@ -51,7 +51,7 @@ pub enum ObjectLifetimeDefault {
 pub struct ResolveBoundVars {
     /// Maps from every use of a named (not anonymous) lifetime to a
     /// `Region` describing how that region is bound
-    pub defs: FxHashMap<OwnerId, FxHashMap<ItemLocalId, ResolvedArg>>,
+    pub defs: FxIndexMap<OwnerId, FxIndexMap<ItemLocalId, ResolvedArg>>,
 
-    pub late_bound_vars: FxHashMap<OwnerId, FxHashMap<ItemLocalId, Vec<ty::BoundVariableKind>>>,
+    pub late_bound_vars: FxIndexMap<OwnerId, FxIndexMap<ItemLocalId, Vec<ty::BoundVariableKind>>>,
 }

compiler/rustc_middle/src/query/mod.rs

@@ -1667,7 +1667,7 @@ rustc_queries! {
         desc { "resolving lifetimes" }
     }
     query named_variable_map(_: hir::OwnerId) ->
-        Option<&'tcx FxHashMap<ItemLocalId, ResolvedArg>> {
+        Option<&'tcx FxIndexMap<ItemLocalId, ResolvedArg>> {
         desc { "looking up a named region" }
     }
     query is_late_bound_map(_: hir::OwnerId) -> Option<&'tcx FxIndexSet<ItemLocalId>> {
@@ -1683,7 +1683,7 @@ rustc_queries! {
         separate_provide_extern
     }
     query late_bound_vars_map(_: hir::OwnerId)
-        -> Option<&'tcx FxHashMap<ItemLocalId, Vec<ty::BoundVariableKind>>> {
+        -> Option<&'tcx FxIndexMap<ItemLocalId, Vec<ty::BoundVariableKind>>> {
         desc { "looking up late bound vars" }
     }