[Bug tree-optimization/68823] [6/7/8 Regression][graphite] tramp3d-v4 compiled with -floop-nest-optimize crashes

[spop at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68823

--- Comment #15 from Sebastian Pop <spop at gcc dot gnu.org> ---
> when DR_NUM_DIMENSIONS (dr1->dr) != DR_NUM_DIMENSIONS (dr2->dr) better "FAIL"?

Yes.
The patch looks good to me.