U.S. stocks extended losses by the middle of the session on Tuesday as crude gave back some of the gains achieved over Monday's rally. Oil fell after Goldman Sachs warned the current push higher is unsustainable and that the industry needs lower prices for longer to rebalance. Vivint Solar (VSLR) has terminated its merger agreement with SunEdison (SUNE) after noting its financial position prevented it from meeting the terms of its deal. The deal was worth nearly $2 billion when announced in mid-2015. Chevron (CVX) slashed its capex budget for 2017-18 to $17 billion from $22 billion. However, the oil company did maintain forecasts for production growth through the end of the decade. TheStreet's Keris Lahiff reports from Wall Street.