Active process termination part of #terminate contains a line that's been a
mystery to me:
| ctxt unwindBlock oldList outerMost |
self isActiveProcess ifTrue:
[ctxt := thisContext.
[ctxt := ctxt findNextUnwindContextUpTo: nil.
ctxt ~~ nil] whileTrue:
[(ctxt tempAt: 2) ifNil:
---> ["N.B. Unlike Context>>unwindTo: we do not set complete (tempAt: 2)
to true."
unwindBlock := ctxt tempAt: 1.
thisContext terminateTo: ctxt.
unwindBlock value]].
thisContext terminateTo: nil.
It appears however that the absence of the assignment (ctxt tempAt: 2 put:
true.) will cause the image crash e.g. in this scenario (probably
irrecoverably; I had to kill it):
| p |
p := [
[ Processor activeProcess terminate ]
ensure: [ Processor activeProcess terminate ].
] fork.
Processor yield.
Transcript show: p isTerminated printString
I already mentioned this anomaly in [1] where it was causing an inability to
close a debugger.
The same algorithm is used in Context >> #resume:[through:] and #unwindTo:,
but always with the assignment.
I was wondering whether the reason for the intentional omission of the
assignment was just saving a line considered useless or whether there was a
deeper idea... Anybody remembers?
Thanks for any advice.
[1]
http://forum.world.st/Bug-in-Process-terminate-Returning-from-unwind-contexts-tp5127570p5128018.html-----
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