Auto merge of #108312 - michaelwoerister:hash-set-not-hash-stable, r=eholk

Do not implement HashStable for HashSet (MCP 533)

This PR removes all occurrences of `HashSet` in query results, replacing it either with `FxIndexSet` or with `UnordSet`, and then removes the `HashStable` implementation of `HashSet`. This is part of implementing [MCP 533](https://github.com/rust-lang/compiler-team/issues/533), that is, removing the `HashStable` implementations of all collection types with unstable iteration order.

The changes are mostly mechanical. The only place where additional sorting is happening is in Miri's override implementation of the `exported_symbols` query.

2 files changed, 4 insertions, 4 deletions

diff --git a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
index fd81b1c6fe1..1a94d4ab8b1 100644
--- a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
+++ b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
@@ -58,7 +58,7 @@ fn reachable_non_generics_provider(tcx: TyCtxt<'_>, cnum: CrateNum) -> DefIdMap<
 
     let mut reachable_non_generics: DefIdMap<_> = tcx
         .reachable_set(())
-        .iter()
+        .items()
         .filter_map(|&def_id| {
             // We want to ignore some FFI functions that are not exposed from
             // this crate. Reachable FFI functions can be lumped into two
@@ -136,7 +136,7 @@ fn reachable_non_generics_provider(tcx: TyCtxt<'_>, cnum: CrateNum) -> DefIdMap<
             };
             (def_id.to_def_id(), info)
         })
-        .collect();
+        .into();
 
     if let Some(id) = tcx.proc_macro_decls_static(()) {
         reachable_non_generics.insert(
diff --git a/compiler/rustc_codegen_ssa/src/target_features.rs b/compiler/rustc_codegen_ssa/src/target_features.rs
index 4301e4fe69b..576e90ae66b 100644
--- a/compiler/rustc_codegen_ssa/src/target_features.rs
+++ b/compiler/rustc_codegen_ssa/src/target_features.rs
@@ -1,7 +1,7 @@
 use rustc_ast::ast;
 use rustc_attr::InstructionSetAttr;
 use rustc_data_structures::fx::FxHashMap;
-use rustc_data_structures::fx::FxHashSet;
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_errors::Applicability;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::DefId;
@@ -418,7 +418,7 @@ pub fn from_target_feature(
 
 /// Computes the set of target features used in a function for the purposes of
 /// inline assembly.
-fn asm_target_features(tcx: TyCtxt<'_>, did: DefId) -> &FxHashSet<Symbol> {
+fn asm_target_features(tcx: TyCtxt<'_>, did: DefId) -> &FxIndexSet<Symbol> {
     let mut target_features = tcx.sess.unstable_target_features.clone();
     if tcx.def_kind(did).has_codegen_attrs() {
         let attrs = tcx.codegen_fn_attrs(did);