segmentation fault: bug in GP (please report).

["John Cremona (Maths)" <cremona@maths.ex.ac.uk>]

This is in 2.0.10.

No problem with...

gp > a=nextprime(10^30)
%18 = 1000000000000000000000000000057
gp > b=nextprime(a+1)
%19 = 1000000000000000000000000000099
gp > c=nextprime(b+1)
%20 = 1000000000000000000000000000211
gp > issquare(Mod(-a*b,c))
%21 = 1

but...

gp > a=nextprime(10^40)
%15 = 10000000000000000000000000000000000000121
gp > b=nextprime(a+1)
%16 = 10000000000000000000000000000000000000139
gp > c=nextprime(b+1)
%17 = 10000000000000000000000000000000000000301
gp > issquare(Mod(-a*b,c))
  ***   segmentation fault: bug in GP (please report).

It would be helpful to know if this is really due to a bug or not, and
if so whether it is known and/or fixed in 2.0.11/12.  Or is there
really an upper bound for (prime) p such that issquare(Mod(a,p)) can
be answered?

John

-- 
John Cremona
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