Fix some minor issues

src/libpanic_abort/lib.rs

@@ -17,10 +17,11 @@
 #![feature(panic_runtime)]
 #![feature(staged_api)]
 #![feature(rustc_attrs)]
-#![feature(raw)]
+
+use core::any::Any;
 
 #[rustc_std_internal_symbol]
-pub unsafe extern "C" fn __rust_cleanup(_: *mut u8) -> core::raw::TraitObject {
+pub unsafe extern "C" fn __rust_panic_cleanup(_: *mut u8) -> *mut (dyn Any + Send + 'static) {
     unreachable!()
 }
 

src/libpanic_unwind/lib.rs

@@ -32,6 +32,7 @@
 #![feature(panic_runtime)]
 
 use alloc::boxed::Box;
+use core::any::Any;
 use core::panic::BoxMeUp;
 
 // If adding to this list, you should also look at libstd::panicking's identical
@@ -70,10 +71,10 @@ extern "C" {
 mod dwarf;
 
 #[no_mangle]
-pub unsafe extern "C" fn __rust_panic_cleanup(payload: *mut u8) -> core::raw::TraitObject {
+pub unsafe extern "C" fn __rust_panic_cleanup(payload: *mut u8) -> *mut (dyn Any + Send + 'static) {
     let payload = payload as *mut imp::Payload;
     let payload = *(payload);
-    core::mem::transmute(imp::cleanup(payload))
+    Box::into_raw(imp::cleanup(payload))
 }
 
 // Entry point for raising an exception, just delegates to the platform-specific

src/libstd/panicking.rs

@@ -67,7 +67,7 @@ cfg_if::cfg_if! {
 extern "C" {
     /// The payload ptr here is actually the same as the payload ptr for the try
     /// intrinsic (i.e., is really `*mut [u64; 2]` or `*mut *mut u8`).
-    fn __rust_panic_cleanup(payload: *mut u8) -> core::raw::TraitObject;
+    fn __rust_panic_cleanup(payload: *mut u8) -> *mut (dyn Any + Send + 'static);
 
     /// `payload` is actually a `*mut &mut dyn BoxMeUp` but that would cause FFI warnings.
     /// It cannot be `Box<dyn BoxMeUp>` because the other end of this call does not depend
@@ -313,7 +313,7 @@ pub unsafe fn r#try<R, F: FnOnce() -> R>(f: F) -> Result<R, Box<dyn Any + Send>>
     // non-cold function, though, as of the writing of this comment).
     #[cold]
     unsafe fn cleanup(mut payload: Payload) -> Box<dyn Any + Send + 'static> {
-        let obj = crate::mem::transmute(__rust_panic_cleanup(&mut payload as *mut _ as *mut u8));
+        let obj = Box::from_raw(__rust_panic_cleanup(&mut payload as *mut _ as *mut u8));
         update_panic_count(-1);
         obj
     }