Change type of mutable_noalias to bool

Author: tmiasko

compiler/rustc_interface/src/tests.rs

@@ -754,7 +754,7 @@ fn test_unstable_options_tracking_hash() {
     tracked!(mir_enable_passes, vec![("DestProp".to_string(), false)]);
     tracked!(mir_opt_level, Some(4));
     tracked!(move_size_limit, Some(4096));
-    tracked!(mutable_noalias, Some(true));
+    tracked!(mutable_noalias, false);
     tracked!(no_generate_arange_section, true);
     tracked!(no_jump_tables, true);
     tracked!(no_link, true);

compiler/rustc_session/src/options.rs

@@ -1437,7 +1437,7 @@ options! {
         "use line numbers relative to the function in mir pretty printing"),
     move_size_limit: Option<usize> = (None, parse_opt_number, [TRACKED],
         "the size at which the `large_assignments` lint starts to be emitted"),
-    mutable_noalias: Option<bool> = (None, parse_opt_bool, [TRACKED],
+    mutable_noalias: bool = (true, parse_bool, [TRACKED],
         "emit noalias metadata for mutable references (default: yes)"),
     nll_facts: bool = (false, parse_bool, [UNTRACKED],
         "dump facts from NLL analysis into side files (default: no)"),

compiler/rustc_ty_utils/src/abi.rs

@@ -259,7 +259,7 @@ fn adjust_for_rust_scalar<'tcx>(
             // LLVM prior to version 12 had known miscompiles in the presence of noalias attributes
             // (see #54878), so it was conditionally disabled, but we don't support earlier
             // versions at all anymore. We still support turning it off using -Zmutable-noalias.
-            let noalias_mut_ref = cx.tcx.sess.opts.unstable_opts.mutable_noalias.unwrap_or(true);
+            let noalias_mut_ref = cx.tcx.sess.opts.unstable_opts.mutable_noalias;
 
             // `&mut` pointer parameters never alias other parameters,
             // or mutable global data