SCM_DEFER_INTS versus error

[Kevin Ryde]

I noticed in the little program below, the thread seems to get hung
after an error in the mainline has done an SCM_DEFER_INTS in strptime
then escaped with an error, apparently not doing an SCM_ALLOW_INTS.

Is there a theory on what should happen with this?  Is an error meant
to re-allow ints or should code be careful to do an ALLOW after any
DEFER?  The latter no doubt makes sense irrespective of what an error
throw does.

Incidentally, I don't think I understand why current-time has a
SCM_DEFER_INTS.  A simple call to time() ought to be safe shouldn't
it?




(use-modules (ice-9 threads))

(begin-thread
 (display "thread started\n")
 (sleep 2)
 (display "thread awake again\n")
 
 (display "thread trying current-time\n")
 (current-time)
 (display "thread done\n"))


(sleep 1)
(catch #t
       (lambda () (strptime "xxx" "%Y"))
       (lambda args
         (display "main caught strptime error\n")))

(sleep 10)
(display "main exiting\n")