Re: fflog seg fault

[Charles Greathouse <charles.greathouse@case.edu>]

With
         GP/PARI CALCULATOR Version 2.4.2 (development CHANGES-1.1971)
           i686 running cygwin (ix86/GMP-4.2.1 kernel) 32-bit version
 compiled: Dec 23 2007, gcc-3.4.4 (cygming special, gdc 0.12, using dmd 0.125)
                 (readline v5.2 enabled, extended help enabled)
I get

>f64 = ffinit(2,64);gen64=ffgen(f64);o = fforder(gen64)
time = 0 ms.
%1 = 6148914691236517205
>fflog(gen64^2,gen64,o)
  *** fflog: incorrect type in FF_log.

With
           GP/PARI CALCULATOR Version 2.4.3 (development svn-12610)
           i586 running mingw (ix86/GMP-4.3.2 kernel) 32-bit version
                    compiled: Oct  1 2010, gcc-4.4.4 (GCC)
               (readline not compiled in, extended help enabled)

                    Copyright (C) 2000-2008 The PARI Group
I get

? f64 = ffinit(2,64);gen64=ffgen(f64);o = fforder(gen64)
%1 = 6148914691236517205
? fflog(gen64^2,gen64,o)
  ***   at top-level: fflog(gen64^2,gen64,
  ***                 ^--------------------
  *** fflog: bug in PARI/GP (Segmentation Fault), please report
  ***   Break loop: type 'break' to go back to GP

With
           GP/PARI CALCULATOR Version 2.4.3 (development svn-12610)
                i586 running mingw (ix86 kernel) 32-bit version
                    compiled: Oct  1 2010, gcc-4.4.4 (GCC)
               (readline not compiled in, extended help enabled)
I get

? f64 = ffinit(2,64);gen64=ffgen(f64);o = fforder(gen64)
%1 = 6148914691236517205
? fflog(gen64^2,gen64,o)
  ***   at top-level: fflog(gen64^2,gen64,
  ***                 ^--------------------
  *** fflog: bug in PARI/GP (Segmentation Fault), please report
  ***   Break loop: type 'break' to go back to GP

Charles Greathouse
Analyst/Programmer
Case Western Reserve University

On Fri, Oct 1, 2010 at 10:58 AM, Dan Bailey <pets0undz@gmail.com> wrote:
> Thanks very much for clarifying usage of fflog!
>
> Unfortunately, none of these suggestions (use a primitive root,
> provide the order, use the daily Windows snapshot binary with and
> without GMP) work on my platform.  They all produce the seg fault.
>
> Later, I'll try this on Linux (via VMware) which may simply solve my
> problem.  Thanks again for all the help!
> Cheers
> Dan
>
>
> On Fri, Oct 1, 2010 at 10:08 AM, Bill Allombert
> <Bill.Allombert@math.u-bordeaux1.fr> wrote:
>> On Fri, Oct 01, 2010 at 08:59:02AM -0400, Dan Bailey wrote:
>>> It does not appear to depend on the RNG seed.  Even after restarting
>>> PARI several times, I consistently get this behavior.
>>
>>> Bill, on which platform is this working for you?
>>
>> On linux, in 32bit and 64bit, with or without GMP.
>>
>> Maybe you can try the daily SVN snapshot (a basic windows binary is available),
>> see http://pari.math.u-bordeaux.fr/download.html).
>>
>> There might be a problem in your input:
>> gen64=ffgen(f64)
>> fflog(gen64^2,gen64)
>>
>> The documentation says:
>> ?? fflog
>> ...
>>   If  no o is given,  assume that g is a primitive root.
>>
>> However, gen64 is not a primitive root (use ffprimroot for that).
>> ? fforder(gen64)
>> %3 = 6148914691236517205
>> ? 2^64-1
>> %4 = 18446744073709551615
>> ? fflog(gen64^2,gen64)
>> %5 = 12297829382473034412
>>
>> You should do
>> ? o = fforder(gen64)
>> %11 = 6148914691236517205
>> ? fflog(gen64^2,gen64,o)
>> %12 = 2
>>
>> Cheers,
>> Bill.
>>
>