Segfault in std with 'ws' ordering

[jakobkroeker]

upstream report:http://www.singular.uni-kl.de:8002/trac/ticket/715#ticket Segfault in std with 'ws' ordering probably caused by illegal(?) options (redSB, redTail)

ring R = (2971),(x,y,z),(ws(5,-7,-3),C);
option(redSB);
option(redTail);
ideal I = 52*y-53*x*z^3-63*z,
         -22*x*y^3-9*x*y^2*z+104*x^2*y^2*z+74,
         54*x*y^2*z+5*x*y*z+84*x*z^2+101;

I =  std(I);

-bug caused in std with ws ordering by illegal(?) options ( redTail)

ring R = (31699),(x,y),(ws(5,-2),C);
short=0;
option(redTail);
ideal I = 28*x*y^2+41*x^2*y+42*x^5,
          57*x^3*y^2-96*x^3,
          81*y^4-52*x^2*y^2+68*x^2*y;
reduce (I, std(I) ) )  ; // expected =0!

output:

> reduce (I, std(I)  );
_[1]=41*x(1)^2*x(2)
_[2]=0
_[3]=68*x(1)^2*x(2)

[fruhbis-kruger-anne]

Just to exclude stupid reasons for the seg-fault: Did you monitor the size during computation? A segfault can also occur due to memory exhaustion -- local examples can grow in a very bad way.

[jakobkroeker]

fixed in http://www.singular.uni-kl.de:8002/trac/changeset/2f3b2753bc2be6d7396f61b99d46ba1977c9388d/git

• redTail is now silently ignored in some rings this may lead to some bugs, too