Boost Log 2.0 : empty Severity level in logs

I'm using Boost-Log 2.0, which has some differences from version 1, and I have a hard time outputting the "Severity" attribute. I'm using the "Boost.Format-style" formatters ``` "%TimeStamp% [%Uptime%] (%LineID%) <%Severity%>: %Message%" ``` `TimeStamp`, `LineID`, and `Message` are `common_attributes`. `Uptime` is an attribute I added using `attrs::timer()`. I thought that `Severity` was automatically added when using `severity_logger`, but apparently it isn't and that's my problem. I get empty severities, eg: ``` 2013-Apr-06 19:21:52.408974 [00:00:00.001337] (3) <>: A warning severity message ``` Notice the empty `<>`. I've tried to add severity using `register_simple_formatter_factory` but then I get the compiler error : ``` error: no matching function for call to ‘register_simple_formatter_factory(const char [9])’ ``` and I don't get why. Here's my code : ``` #include <iostream> #include <boost/log/common.hpp> #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/sinks/sync_frontend.hpp> #include <boost/log/sinks/text_ostream_backend.hpp> #include <boost/log/utility/setup/file.hpp> #include <boost/log/utility/setup/common_attributes.hpp> #include <boost/log/utility/setup/formatter_parser.hpp> #include <boost/log/sources/severity_logger.hpp> #include <boost/log/sources/severity_feature.hpp> #include <boost/log/sources/record_ostream.hpp> #include <boost/log/attributes.hpp> using namespace std; namespace logging = boost::log; namespace expr = boost::log::expressions; namespace attrs = boost::log::attributes; namespace src = boost::log::sources; namespace keywords = boost::log::keywords; enum severity_level { DEBUG, INFO, WARNING, ERROR, CRITICAL }; BOOST_LOG_INLINE_GLOBAL_LOGGER_DEFAULT(my_logger, src::severity_logger_mt< severity_level> ) // The formatting logic for the severity level template< typename CharT, typename TraitsT > inline std::basic_ostream< CharT, TraitsT >& operator<< ( std::basic_ostream< CharT, TraitsT >& strm, severity_level lvl) { static const char* const str[] = { "DEBUG", "INFO", "WARNING", "ERROR", "CRITICAL" }; if (static_cast< std::size_t >(lvl) < (sizeof(str) / sizeof(*str))) strm << str[lvl]; else strm << static_cast< int >(lvl); return strm; } void init() { // logging::register_simple_formatter_factory< severity_level >("Severity"); logging::add_file_log( keywords::file_name = "blop.log", keywords::auto_flush = true, keywords::open_mode = (std::ios::out | std::ios::app), keywords::format = "%TimeStamp% [%Uptime%] (%LineID%) <%Severity%>: %Message%" ); logging::add_common_attributes(); logging::core::get()->add_global_attribute("Uptime", attrs::timer()); } int main(int argc, const char *argv[]) { init(); src::severity_logger_mt< severity_level > lg = my_logger::get(); BOOST_LOG_SEV(lg, DEBUG) << "A debug severity message"; BOOST_LOG_SEV(lg, INFO) << "An informational severity message"; BOOST_LOG_SEV(lg, WARNING) << "A warning severity message"; BOOST_LOG_SEV(lg, ERROR) << "An error severity message"; BOOST_LOG_SEV(lg, CRITICAL) << "A critical severity message"; return 0; } ``` Notice the commented-out line : ``` // logging::register_simple_formatter_factory< severity_level >("Severity"); ``` which produces the mentioned error. I compile it with: ``` g++ main.cpp -Wall -DBOOST_ALL_DYN_LINK -lboost_system -lboost_log_setup -lboost_log -lboost_filesystem -lboost_date_time -lboost_thread -o main ```