Variable Machine::runUntilTime is used before initialization

[soyWXY]

Description

In C++, a class member Machine::runUntilTime, whose type is int, won't be initialized automatically. The only place that sets runUntilTime is in Machine::Debugger(), but the snippet that invokes Debugger() checks the runUntilTime value first:

if (singleStep && (runUntilTime <= kernel->stats->totalTicks))
    Debugger();

This leads to a used-before-set undefined behavior.

Suggested Solution

Initialize Machine::runUntilTime in the constructor Machine::Machine().