why I am getting garbage values by the function getMemberNames() in release mode

I am getting garbage values in a vector by the getMemberNames() function call of jsoncpp.dll in release mode in the visual studio. It is working fine in debug mode.

Json::Value dataOfFSISubReport = fileOPerations.GetJsonData(FSISubReportJsonFile);

std::vector<std::string> dataAttributes = dataOfCarpetTenementArea.getMemberNames();