diff --git a/compiler/rustc_mir_transform/src/simplify.rs b/compiler/rustc_mir_transform/src/simplify.rs
index a54e548ad70ab..db933da641371 100644
--- a/compiler/rustc_mir_transform/src/simplify.rs
+++ b/compiler/rustc_mir_transform/src/simplify.rs
@@ -82,7 +82,7 @@ pub(super) fn simplify_cfg<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
     remove_dead_blocks(body);
 
     // FIXME: Should probably be moved into some kind of pass manager
-    body.basic_blocks_mut().raw.shrink_to_fit();
+    body.basic_blocks.as_mut_preserves_cfg().shrink_to_fit();
 }
 
 impl<'tcx> crate::MirPass<'tcx> for SimplifyCfg {