import python

predicate reaches_exit(Name u) {
    u.uses(_) and 
    exists(ControlFlowNode f, BasicBlock b | 
        f.getNode() = u and f.getBasicBlock() = b |
        b.reachesExit()
    )
}

from Name u
where reaches_exit(u) and u.getVariable() instanceof GlobalVariable
select u.toString()