Function panic_in_cleanup 

fn panic_in_cleanup() -> !

🔬This is a nightly-only experimental API. (panic_internals)

Panics because we are unwinding out of a destructor during cleanup.

This is a separate function to avoid the codesize impact of each crate containing the string to pass to panic_nounwind.

This function is called directly by the codegen backend, and must not have any extra arguments (including those synthesized by track_caller).