I encountered the following issue in mprimdec.lib::GTZmod:https://github.com/Singular/Sources/blob/spielwiese/Singular/LIB/mprimdec.lib#L635
In my case it is:
ring basering = 0,(x,y,z),dp;
ring Rloc = (0,x,y,z), dummy,(dp(3),C);
Singular 3.x used to accept this and applied dp to the sole variable dummy.
But now Singular 4.x complains that dp(3) wants 3 variables.
So two things:
* Singular behavior changed, and this makes sense to me, although one might want to apply the same ordering to a ring with more variables and cannot directly use ordstr for that anymore,
* not sure what is intended in the Rloc creation regarding ordering, so I have no idea how to properly fix it.