1 error[E0282]: type annotations needed
2 --> $DIR/issue-16966.rs:2:5
4 LL | panic!(std::default::Default::default());
5 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot infer type for type parameter `M` declared on the function `begin_panic`
7 = note: this error originates in the macro `$crate::panic::panic_2015` (in Nightly builds, run with -Z macro-backtrace for more info)
9 error: aborting due to previous error
11 For more information about this error, try `rustc --explain E0282`.