core::intrinsics::try

pub unsafe extern "rust-intrinsic" fn try(f: fn(*mut u8), data: *mut u8) -> *mut u8

Unstable (core_intrinsics #0)

: intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library

Rust's "try catch" construct which invokes the function pointer f with the data pointer data, returning the exception payload if an exception is thrown (aka the thread panics).