Allow setting the panic hook with parity-clib (#9292)

* Allow setting the panic hook with parity-clib

* Make all FFI functions unsafe

* Fix comment

* Fix concern

parity/lib.rs

@@ -57,7 +57,6 @@ extern crate ethcore_transaction as transaction;
 extern crate ethereum_types;
 extern crate ethkey;
 extern crate kvdb;
-extern crate panic_hook;
 extern crate parity_hash_fetch as hash_fetch;
 extern crate parity_ipfs_api;
 extern crate parity_local_store as local_store;

parity/main.rs

@@ -253,7 +253,8 @@ fn main_direct(force_can_restart: bool) -> i32 {
 				panic_hook::set_with({
 					let e = exit.clone();
 					let exiting = exiting.clone();
-					move || {
+					move |panic_msg| {
+						let _ = stdio::stderr().write_all(panic_msg.as_bytes());
 						if !exiting.swap(true, Ordering::SeqCst) {
 							*e.0.lock() = ExitStatus {
 								panicking: true,