bt broken?

examples/panic.rs

+//! Changing the panicking behavior
+//!
+//! The easiest way to change the panicking behavior is to use a different [panic handler crate][0].
+//!
+//! [0]: https://crates.io/keywords/panic-impl
+
+#![no_main]
+#![no_std]
+
+// Pick one of these panic handlers:
+
+// `panic!` halts execution; the panic message is ignored
+// extern crate panic_halt;
+// extern crate panic_abort;
+
+// Reports panic messages to the host stderr using semihosting
+// NOTE to use this you need to uncomment the `panic-semihosting` dependency in Cargo.toml
+extern crate panic_semihosting;
+
+// Logs panic messages using the ITM (Instrumentation Trace Macrocell)
+// NOTE to use this you need to uncomment the `panic-itm` dependency in Cargo.toml
+// extern crate panic_itm;
+
+use cortex_m_rt::entry;
+
+#[entry]
+fn main() -> ! {
+    panic!("Oops")
+}