error[E0597]: `mutex` does not live long enough
  --> $DIR/format-args-temporaries-in-write.rs:41:27
   |
LL |         write!(Out, "{}", mutex.lock()) /* no semicolon */
   |                           ^^^^^^^^^^^^
   |                           |
   |                           borrowed value does not live long enough
   |                           a temporary with access to the borrow is created here ...
LL |
LL |     };
   |     -- ... and the borrow might be used here, when that temporary is dropped and runs the `Drop` code for type `MutexGuard`
   |     |
   |     `mutex` dropped here while still borrowed
   |
help: consider adding semicolon after the expression so its temporaries are dropped sooner, before the local variables declared by the block are dropped
  --> $SRC_DIR/core/src/macros/mod.rs:LL:COL
   |
LL |         $dst.write_fmt($crate::format_args!($($arg)*));
   |                                                       +

error[E0597]: `mutex` does not live long enough
  --> $DIR/format-args-temporaries-in-write.rs:47:29
   |
LL |         writeln!(Out, "{}", mutex.lock()) /* no semicolon */
   |                             ^^^^^^^^^^^^
   |                             |
   |                             borrowed value does not live long enough
   |                             a temporary with access to the borrow is created here ...
LL |
LL |     };
   |     -- ... and the borrow might be used here, when that temporary is dropped and runs the `Drop` code for type `MutexGuard`
   |     |
   |     `mutex` dropped here while still borrowed
   |
help: consider adding semicolon after the expression so its temporaries are dropped sooner, before the local variables declared by the block are dropped
  --> $SRC_DIR/core/src/macros/mod.rs:LL:COL
   |
LL |         $dst.write_fmt($crate::format_args_nl!($($arg)*));
   |                                                          +

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0597`.