KLabelConstants not unique in KEQ

[kheradmand]

I am trying to use KEQ for establishing equivalence between two programs written in two languages:

module COMMON
syntax Vals ::= @nil 
...
endmodule

module L1
imports COMMON
...
endmodule

module L2
imports COMMON
...
endmodule

details here

I am not getting the result I expect. One problem is that the following equality does not hold:
@nil(.KList@BASIC-K) =? @nil(.KList@BASIC-K).
The reason is that the two @nils have different KLables (with different ordinal numbers but the same hash code).

I was wondering what the problem may be.

@daejunpark any ideas ?