sll2@cunixa.cc.columbia.edu (Steven L Levitt) (04/28/91)
While just fooling around with MIT Scheme, I decided to do something
which was clearly stupid, such as tracing TRACE, and then using it on something
like the primitive procedure -. I suspected that Scheme would enter an
infinite loop and I would have to hit C-c C-c to get it out again, and that
would be all that would happen. Instead, the Emacs status line began to show
Scheme rapidly switching from running the trace to garbage collection and back
again. The first time I tried this, something, possibly the kernal, alerted me
that there had actually been a hardware error. Upon repeated attempts, though,
I found that I could not bring about this error message consistently, and I
also am not sure if there was really a hardware error involved. Does anyone
have an explanation for Scheme's behavior? Please send relplies to
sll2@cunixa.cc.columbia.edu or post here (transcript follows).
(trace trace)
;No value
(trace -)
[Entering #[compound-procedure 2]
Args: #[compound-procedure 3 -]]
Automagically impurifying an object...
;Quit!
(untrace -)
>> A hardware fault has occurred.
>> [signal 11 (SIGSEGV), code 3]
>> The trap occurred while processing an earlier trap.
>> [The earlier trap raised signal 11 (SIGSEGV), code 3.]
>> Successful recovery is unlikely.
Choose one of the following actions:
D = dump core
I = terminate immediately
N = terminate normally
R = attempt recovery
Q = terminate normally
Action -> d
------
Steven L. Levitt
This is a temporary .sig file until I can find something intellegent to say.