Disable SimplifyBranchSame optimization for now

2021-10-03 22:58:24 +02:00
parent 20489eaca2
commit dd9b4763a4
1 changed files with 6 additions and 0 deletions
--- a/compiler/rustc_mir_transform/src/simplify_try.rs
+++ b/compiler/rustc_mir_transform/src/simplify_try.rs
@@ -544,6 +544,12 @@ pub struct SimplifyBranchSame;

 impl<'tcx> MirPass<'tcx> for SimplifyBranchSame {
    fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
+        // This optimization is disabled by default for now due to
+        // soundness concerns; see issue #89485 and PR #89489.
+        if !tcx.sess.opts.debugging_opts.unsound_mir_opts {
+            return;
+        }
+
        trace!("Running SimplifyBranchSame on {:?}", body.source);
        let finder = SimplifyBranchSameOptimizationFinder { body, tcx };
        let opts = finder.find();