diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_monomorphize/src/collector.rs | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/compiler/rustc_monomorphize/src/collector.rs b/compiler/rustc_monomorphize/src/collector.rs index 173030e0326..e90e32ebebb 100644 --- a/compiler/rustc_monomorphize/src/collector.rs +++ b/compiler/rustc_monomorphize/src/collector.rs @@ -949,6 +949,9 @@ fn visit_instance_use<'tcx>( } ty::InstanceKind::DropGlue(_, None) => { // Don't need to emit noop drop glue if we are calling directly. + // + // Note that we also optimize away the call to visit_instance_use in vtable construction + // (see create_mono_items_for_vtable_methods). if !is_direct_call { output.push(create_fn_mono_item(tcx, instance, source)); } @@ -1177,8 +1180,13 @@ fn create_mono_items_for_vtable_methods<'tcx>( output.extend(methods); } - // Also add the destructor. - visit_drop_use(tcx, impl_ty, false, source, output); + // Also add the destructor, if it's necessary. + // + // This matches the check in vtable_allocation_provider in middle/ty/vtable.rs, + // if we don't need drop we're not adding an actual pointer to the vtable. + if impl_ty.needs_drop(tcx, ty::TypingEnv::fully_monomorphized()) { + visit_drop_use(tcx, impl_ty, false, source, output); + } } /// Scans the CTFE alloc in order to find function pointers and statics that must be monomorphized. |