Dear all,

I'm reporting what seems to me as a bug in the SMTLIB library in maple. 

    |\^/|     Maple 2026 (X86 64 LINUX)
._|\|   |/|_. Copyright (c) Maplesoft, a division of Waterloo Maple Inc. 2026
 \  MAPLE  /  All rights reserved. Maple is a trademark of
 <____ ____>  Waterloo Maple Inc.
      |       Type ? for help.
> SMTLIB:-Satisfiable({x^2=2,y^2=2,x<y});
                                     true

> SMTLIB:-Satisfiable({x^2=2,y^2=2,y<x});
                                     false

> SMTLIB:-Satisfiable({x^2=2,a^2=2,a<x});
                                     true

The Satisfiable command do not output the correct decision on two formulas of equivalent realization by switching x<y (output SAT) to y<x (output UNSAT). I suspect this is because some alphabetical order depandance in the variables as for a<y we get SAT again.

I tried to feed Z3 with the code given by ToString on the problematic formula and I get two different outputs :

• on the Z3 version 4.8.12 from the ubuntu repository (apt install) I also get the wrong UNSAT output;
• one the Z3 version 4.17.0 build from the official github repository I finally get the correct SAT output.

Thus, I suspect a version problem in SMTLIB that do not take in account the last updates made in SMT solvers (Z3?).

Many thanks for considering my problem!