Re. Strangely modified variables

[Mark Chimley <M.Chimley@bristol.ac.uk>]

Many thanks, Gerhard, for pointing me in the right direction. The
problem
turned out to be a stack fault as you suspected. Interestingly, it was
caused by GEN P not being initialised. Obviously, the GENs must be
defined before the stack is initialised, so the pointers begin life
pointing to some miscellaneous part of memory. My first assignment to P
was with stoi (l), where l is a long, initialised to 0. For some reason,
P = stoi (0) doesn't return a value within the PARI stack, so P
continues to point into space! Simply initialising l with 1 instead,
solved the problem.

Mark.
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Mark Chimley,
Department Of Mathematics,
University Of Bristol
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