🔬 This is a nightly-only experimental API. (
internal details of the implementation of the
panic! and related macros
Panic support for libcore
The core library cannot define panicking, but it does declare panicking. This means that the functions inside of libcore are allowed to panic, but to be useful an upstream crate must define panicking for libcore to use. The current interface for panicking is:
fn panic_impl(fmt: fmt::Arguments, file_line_col: &(&'static str, u32, u32)) -> !Run
This definition allows for panicking with any general message, but it does not
allow for failing with a
Box<Any> value. The reason for this is that libcore
is not allowed to allocate.
This module contains a few other panicking functions, but these are just the necessary lang items for the compiler. All panics are funneled through this one function. Currently, the actual symbol is declared in the standard library, but the location of this may change over time.