Call the panic hook for non-unwind panics in proc-macros

library/proc_macro/src/lib.rs

@@ -30,6 +30,7 @@
 #![feature(maybe_uninit_write_slice)]
 #![feature(negative_impls)]
 #![feature(new_uninit)]
+#![feature(panic_can_unwind)]
 #![feature(restricted_std)]
 #![feature(rustc_attrs)]
 #![feature(min_specialization)]