error[E0080]: evaluation of `Fail::::C` failed --> $DIR/collect-in-dead-vtable.rs:11:19 | LL | const C: () = panic!(); | ^^^^^^^^ the evaluated program panicked at 'explicit panic', $DIR/collect-in-dead-vtable.rs:11:19 | = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) note: erroneous constant encountered --> $DIR/collect-in-dead-vtable.rs:25:21 | LL | let _ = Fail::::C; | ^^^^^^^^^^^^ note: the above error was encountered while instantiating `fn as MyTrait>::not_called` --> $DIR/collect-in-dead-vtable.rs:34:40 | LL | let gen_vtable: &dyn MyTrait = &v; // vtable "appears" here | ^^ error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0080`.