Boost log - argg!

Rarrgh!

Boost log is driving me crazy - logically identical code is giving me 2 different results. I can get their sample file logging code to work, but when I port it to my own Logger class, nothing gets written to the file (default.log in this case).

Below is my Logger class implementation.

Logger.cpp

#include "Logger.h"

namespace logging = boost::log;
namespace sinks = boost::log::sinks;
namespace src = boost::log::sources;
namespace expr = boost::log::expressions;
namespace attrs = boost::log::attributes;
namespace keywords = boost::log::keywords;

namespace dhlogging {

Logger::Logger(std::string fileName)
{
    initialize(fileName);
}

Logger::Logger(Logger const&)
{
}

Logger::~Logger()
{

}

Logger* Logger::logger_ = nullptr;
Logger* Logger::getInstance(std::string logFile)
{
    if ( Logger::logger_ == nullptr ) {
        logging::add_file_log( logFile );

        logging::core::get()->set_filter
        (
            logging::trivial::severity >= logging::trivial::info
        );

        logging::add_common_attributes();
        Logger::logger_ = new Logger(logFile);
    }

    return Logger::logger_;
}

void Logger::initialize(std::string fileName)
{   
    BOOST_LOG(log_) << "Hello, World!";
    BOOST_LOG_SEV(log_, info) << "Hello, World2!";
}

void Logger::logInfo(std::string message)
{
    BOOST_LOG_SEV(log_, info) << message;
}

void Logger::logDebug(std::string message)
{
    BOOST_LOG_SEV(log_, debug) << message;
}

void Logger::logWarn(std::string message)
{
    BOOST_LOG_SEV(log_, warning) << message;
}

void Logger::logError(std::string message)
{
    BOOST_LOG_SEV(log_, error) << message;
}

void Logger::logFatal(std::string message)
{
    BOOST_LOG_SEV(log_, fatal) << message;
}

}

int main(int, char*[])
{
    logging::add_common_attributes();

    using namespace logging::trivial;

    dhlogging::Logger::getInstance()->logInfo("himom");

    return 0;
}

Logger.h

#ifndef LOGGER_H_
#define LOGGER_H_

#include <boost/log/core.hpp>
#include <boost/log/trivial.hpp>
#include <boost/log/expressions.hpp>
#include <boost/log/sinks/text_file_backend.hpp>
#include <boost/log/utility/setup/file.hpp>
#include <boost/log/utility/setup/common_attributes.hpp>
#include <boost/log/sources/severity_logger.hpp>
#include <boost/log/sources/record_ostream.hpp>

namespace logging = boost::log;
namespace sinks = boost::log::sinks;
namespace src = boost::log::sources;
namespace expr = boost::log::expressions;
namespace attrs = boost::log::attributes;
namespace keywords = boost::log::keywords;

using namespace logging::trivial;

namespace dhlogging {
class Logger {

public:
    static Logger* getInstance(std::string logFile = "default.log");

    void logInfo(std::string message);
    void logDebug(std::string message);
    void logWarn(std::string message);
    void logError(std::string message);
    void logFatal(std::string message);


private:
    Logger(std::string fileName);
    Logger(Logger const&);
    Logger& operator=(Logger const&);
    virtual ~Logger();

    void initialize(std::string fileName);

    src::severity_logger< severity_level > log_;

    static Logger* logger_; // singleton instance
};
}
#endif /* LOGGER_H_ */

I'm on debian 7 64bit. Everything compiles fine. I compile with these commands:

g++ -o build/Logger.o -c -std=c++11 -Wall -g -O0 -DBOOST_LOG_DYN_LINK -DDEBUG src/Logger.cpp
g++ -o build/logtest build/Logger.o -lboost_log -lboost_log_setup -lboost_date_time -lboost_thread -lboost_wave -lboost_regex -lboost_program_options

I've posted this on StackOverflow, but so far, no dice. If anyone has any ideas, I'd be very grateful! :)

Jarrett