Segmentation Fault with Multivariate Polynomial Ring

[stankewicz]

This is an example over a 2- variable polynomial ring over QQ (although sage does not see K as isomorphic to QQ)

----------------------------------------------------------------------
| Sage Version 3.4.1, Release Date: 2009-04-21                       |
| Type notebook() for the GUI, and license() for information.        |
----------------------------------------------------------------------
sage: K.<j> = NumberField(x-1728)
sage: R.<b,c> = K[]
sage: f = b-j*c


------------------------------------------------------------
Unhandled SIGSEGV: A segmentation fault occured in SAGE.
This probably occured because a *compiled* component
of SAGE has a bug in it (typically accessing invalid memory)
or is not properly wrapped with _sig_on, _sig_off.
You might want to run SAGE under gdb with 'sage -gdb' to debug this.
SAGE will now terminate (sorry).
------------------------------------------------------------

Note that this does not pose a problem if the number field is not QQ

sage: K.<j> = NumberField(x^2 - 2)
sage: R.<b,c> = K[]
sage: f = b-j*c
sage: f
b + (-j)*c

Nor if the Polynomial Ring is Univariate

sage: F.<i> = NumberField(x-1728)
sage: S.<y> = F[]
sage: y - i
y - 1728
sage: g = y - i
sage: g = i*y^2 + 1
sage: g
1728*y^2 + 1

Also note that this has nothing to do with Pari's occasional trouble with the ordering of variables

sage: K.<j> = NumberField(x-1728)
sage: R.<k,l> = K[]
sage: f = k - j*l


------------------------------------------------------------
Unhandled SIGSEGV: A segmentation fault occured in SAGE.
This probably occured because a *compiled* component
of SAGE has a bug in it (typically accessing invalid memory)
or is not properly wrapped with _sig_on, _sig_off.
You might want to run SAGE under gdb with 'sage -gdb' to debug this.
SAGE will now terminate (sorry).
------------------------------------------------------------

[burcin]

The patch attached to #7582 fixes this. I'm closing this as a duplicate.