Re: Segmentation fault during output()

["Karim Belabas" <Karim.Belabas@math.u-bordeaux1.fr>]

* Chris Condrat [2006-03-14 06:08]:
> I'm using a CATCH(errpile) {} TRY {} ENDCATCH; block to capture stack
> overflows and dump the last-known-good output to a file, before
> resetting the avma and starting again. The flow of the program is much
> like:
> 
> loop
> {
>     CATCH (errpile)
>     {
>         avma = last_known_good_avma;
>         output(last_known_good_formula);
>         avma = top_of_the_stack;
>         // Get ready to start again.
>         CATCH_RELEASE();
>     } TRY {
>         // computations with garbage collecting which will probably overflow.
>     } ENDCATCH;
> } while(still_more_to_do);
> 
> 
> This works great for the first four or so runs (that is, overflows),
> but on the fifth run, it segmentation faults while attempting to write
> the GEN to the output.  I have narrowed it down specifically to when
> it tries to output the GEN.
> 
> Am I doing something wrong here?  Any suggestions would be appreciated as well.

I'm not sure. If a stack overflow occurs during
'output(last_known_good_formula)', we're in trouble.

Doesn't "random GC" [ using if (low_stack()) constructs ] address your
problem with less hassle ?

In doubt, feel free to send me your code, I'll have a look.
(And possibly post whatever solution I could come with if this
turns out to be of general interest.)

Cheers,

    K.B.
-- 
Karim Belabas                  Tel: (+33) (0)5 40 00 26 17
Universite Bordeaux 1          Fax: (+33) (0)5 40 00 69 50
351, cours de la Liberation    http://www.math.u-bordeaux.fr/~belabas/
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