Assert that GlobalCtxt is Sync

Author: Zoxc

src/librustc/ty/context.rs

@@ -58,7 +58,7 @@ use rustc_data_structures::stable_hasher::{HashStable, hash_stable_hashmap,
                                            StableVec};
 use arena::{TypedArena, SyncDroplessArena};
 use rustc_data_structures::indexed_vec::IndexVec;
-use rustc_data_structures::sync::{Lrc, Lock, WorkerLocal};
+use rustc_data_structures::sync::{self, Lrc, Lock, WorkerLocal};
 use std::any::Any;
 use std::borrow::Borrow;
 use std::cmp::Ordering;
@@ -1179,6 +1179,8 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             output_filenames: Arc::new(output_filenames.clone()),
         };
 
+        sync::assert_send_val(&gcx);
+
         tls::enter_global(gcx, f)
     }