@malex984 
I guess, the attrib check should be removed and is done appropriately by std() and groebner()?
Nevertheless,I do not yet understand the isSB and isGB flags:
```
ring rng = 0,x,dp;
ideal i = 5*x,x;
attrib( i, "isSB", 1);
attrib( i, "isGB", 1);
std(i);
// _[1]=x
groebner(i);
// _[1]=x
```