                                         maxRes = max(fabs(inf_coeff), fabs(sup_coeff));
                                         maxMul = max(fabs(tmp1), fabs(tmp2));
 
-                                        inf_coeff = inf_coeff + tmp1 + (maxRes + maxMul)*ulp;
+                                        inf_coeff = inf_coeff + tmp1 - (maxRes + maxMul)*ulp;
                                         sup_coeff = sup_coeff + tmp2 + (maxRes + maxMul)*ulp;
                                     }
                                 }

                    float_type tmp1, tmp2;
                    elina_double_interval_mul_cst_coeff(&tmp1, &tmp2, mu_inf, mu_sup, old_inf_coeff, old_sup_coeff);

                    atomicAdd(&inf_cst[n], tmp1 + min_denormal);
                    atomicAdd(&sup_cst[n], tmp2 + min_denormal);
                }
                else if(old_sup_coeff < 0)

                maxRes = max(fabs(inf_cst), fabs(sup_cst));
                maxMul = max(fabs(tmp1), fabs(tmp2));

                inf_cst += tmp1 - (maxRes + maxMul)*ulp - min_denormal;
                sup_cst += tmp2 + (maxRes + maxMul)*ulp + min_denormal;
            }
        }
