Re: [Boost-users] Log: [Bug] Setting attribute makes log entry disappear

Florian Lindner wrote:

Hello,

I have a tracer, that should log going in and out of a function:

class Tracer { public: Tracer(Logger logger, std::string function, std::string file) : _logger(logger), _function(function), _file(file) {}

~Tracer() { using namespace boost::log; // attribute_cast(core::get()- get_global_attributes()["Line"]).set(1); attribute_caststd::string>(core::get()- get_global_attributes()["File"]).set(_file); attribute_caststd::string>(core::get()- get_global_attributes()["Function"]).set(_function); BOOST_LOG_SEV(_logger, trivial::severity_level::trace) << "Leaving " << _function; }

private: Logger _logger; std::string _function; std::string _file; };

This works fine, but as soon as I uncomment the line that sets the Line attribut I don't get any Leaving messages anymore.

The attributes are added beforehand like that:

using namespace boost::log; add_common_attributes(); core::get()->add_global_attribute("Scope", attributes::named_scope()); core::get()->add_global_attribute("Rank", attributes::constant<int>(5)); core::get()->add_global_attribute("Line", attributes::mutable_constant<int>(5)); core::get()->add_global_attribute("File", attributes::mutable_constantstd::string("")); core::get()->add_global_attribute("Function", attributes::mutable_constantstd::string(""));

Setting all other attributes, similiar to Line works fine. I'm puzzled because Line does not seem to be a reserved name, it works somewhere else and the boost::log sources reveal no relevant usages of that name.

Sorry, forgot to add what the actual problem is: The log message (Leaving...) is simply discarded. All log message before and after that are printed fine, but this one.