merge rustc history

Author: RalfJung

src/tools/miri/src/lib.rs

@@ -1,5 +1,4 @@
 #![feature(rustc_private)]
-#![feature(map_first_last)]
 #![feature(map_try_insert)]
 #![feature(never_type)]
 #![feature(try_blocks)]

src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.rs

@@ -1,7 +1,7 @@
 //@revisions: extern_block definition both
 #![feature(rustc_attrs, c_unwind)]
 
-#[cfg_attr(any(definition, both), rustc_allocator_nounwind)]
+#[cfg_attr(any(definition, both), rustc_nounwind)]
 #[no_mangle]
 extern "C-unwind" fn nounwind() {
     //[definition]~^ ERROR: abnormal termination: the program aborted execution
@@ -11,7 +11,7 @@ extern "C-unwind" fn nounwind() {
 
 fn main() {
     extern "C-unwind" {
-        #[cfg_attr(any(extern_block, both), rustc_allocator_nounwind)]
+        #[cfg_attr(any(extern_block, both), rustc_nounwind)]
         fn nounwind();
     }
     unsafe { nounwind() }