Assertion violation at old_interval.cpp:176 (opt)

[rainoftime]

Hi, for the following formula, z3 9f6a733 throws an assertion violation

ASSERTION VIOLATION
 File: ../src/smt/old_interval.cpp
 Line: 176
 lower != upper || !l_open || !u_open
 (C)ontinue, (A)bort, (S)top, (T)hrow exception, Invoke (G)DB

(set-logic QF_NRA)
(declare-fun _substvar_18_ () Real)
(set-option :opt.optsmt_engine symba)
(declare-const r3 Real)
(declare-const r5 Real)
(declare-const r6 Real)
(declare-const r8 Real)
(declare-const r9 Real)
(declare-const r13 Real)
(declare-const r19 Real)
(declare-const r22 Real)
(assert (>= (/ (- 0.399331 r3 r19 r13) r19) 33.0 r19 _substvar_18_))
(minimize r3)
(maximize r5)
(maximize r6)
(minimize r8)
(minimize r9)
(minimize r13)
(maximize r22)
(check-sat)