Zero-width volume MML macro crashes the program

[Gumball2415]

Steps to reproduce: enter 15:0 in the volume envelope of any instrument

[Gumball2415]

integer division by zero error on this line, when m_iValueDiv == 0

char CSeqConversionDefault::GetValue()
{
	// do not use float division
	int Val = m_iCurrentValue;
	if (Val > m_iMaxValue) Val = m_iMaxValue;
	if (Val < m_iMinValue) Val = m_iMinValue;
	if (++m_iRepeatCounter >= m_iRepeat) {
		m_iValueMod += m_iValueInc;
		m_iCurrentValue += m_iValueMod / m_iValueDiv; // division by zero!
		m_iValueMod %= m_iValueDiv;
		m_iRepeatCounter = 0;
		if (++m_iCounter >= m_iValueDiv)
			m_bReady = false;
	}
	return Val;
}