Let guard frames optionally pass through unwinding.

We have a bug in that when an exception occurs in a context
called from obj_print, the guard for stopping continuation
captures across obj_print also unintentially blocks the
unwinding. Let's make the unwinding blockage optional

* unwind.c (uw_unwind_to_exit_point): If a UW_GUARD is
encountered, do not abort if the uw_ok flag is set;
keep unwinding.
(uw_push_guard): New uw_ok argument, initializes the
uw_ok member of a guard frame.

* unwind.h (struct uw_guard): New struct type.
(union uw_frame): New member gu of type struct uw_guard.
(uw_push_guard): Declaration updated.

* ftw.c (ftw_callback): Pass zero as new uw_push_guard
argument: no unwinding across the POSIX library function ftw.

* glob.c (errfunc_thunk): Likewise, no unwinding across
the library function glob.

* lib.c (obj_print): Pass 1 as new uw_push_guard argument:
continuations can't be captured, but unwinding is okay.

0 files changed, 0 insertions, 0 deletions