1 files changed, 2 insertions, 2 deletions
diff --git a/compiler/rustc_codegen_ssa/src/mir/block.rs b/compiler/rustc_codegen_ssa/src/mir/block.rs
index be5458523d1..26e429034dc 100644
--- a/compiler/rustc_codegen_ssa/src/mir/block.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/block.rs
@@ -540,7 +540,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     //                \-------/
                     //
                     let virtual_drop = Instance {
-                        def: ty::InstanceDef::Virtual(drop_fn.def_id(), 0),
+                        def: ty::InstanceDef::Virtual(drop_fn.def_id(), 0), // idx 0: the drop function
                         args: drop_fn.args,
                     };
                     debug!("ty = {:?}", ty);
@@ -581,7 +581,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     //
                     // SO THEN WE CAN USE THE ABOVE CODE.
                     let virtual_drop = Instance {
-                        def: ty::InstanceDef::Virtual(drop_fn.def_id(), 0),
+                        def: ty::InstanceDef::Virtual(drop_fn.def_id(), 0), // idx 0: the drop function
                         args: drop_fn.args,
                     };
                     debug!("ty = {:?}", ty);