Приведенный ниже пример программы работает нормально, но valgrind показывает, что 520 байт в 6 блоках все еще доступны после выхода.
#include <iostream>
#include <string>
#include <boost/log/common.hpp>
#include <boost/log/sources/logger.hpp>
#include <boost/log/utility/setup/file.hpp>
#include <boost/phoenix/bind/bind_member_function.hpp>
#include <boost/shared_ptr.hpp>
namespace bl = boost::log;
namespace bp = boost::phoenix;
enum class MySeverityLevel
{
panic,
alert,
critical,
error,
warning,
notice,
info,
debug
};
BOOST_LOG_ATTRIBUTE_KEYWORD(Severity, "Severity", MySeverityLevel)
BOOST_LOG_ATTRIBUTE_KEYWORD(Channel, "Channel", std::string)
class Logger
{
public:
Logger(const std::string& CH, const MySeverityLevel SEV):
m_log(bl::keywords::channel = CH), m_channel(CH), m_severityMax(SEV)
{
m_sink = bl::add_file_log
(
bl::keywords::file_name = CH + ".log",
bl::keywords::filter = bp::bind(&Logger::filter, this, Channel.or_none(), Severity.or_none())
);
}
~Logger()
{
this->terminate();
}
void terminate()
{
if (m_sink)
{
bl::core::get()->remove_sink(m_sink);
m_sink->flush();
m_sink.reset();
}
}
void panic(const std::string& S)
{
BOOST_LOG_SEV(m_log, MySeverityLevel::panic) << S;
}
void debug(const std::string& S)
{
BOOST_LOG_SEV(m_log, MySeverityLevel::debug) << S;
}
private:
using ChannelValue = bl::value_ref<std::string, tag::Channel>;
using MySeverityLevelValue = bl::value_ref<MySeverityLevel, tag::Severity>;
bool filter(const ChannelValue& CH, const MySeverityLevelValue& SEV) const
{
if (CH && SEV)
{
return (CH.get() == m_channel) && (SEV.get() <= m_severityMax);
}
else
{
return false;
}
}
bl::sources::severity_channel_logger<MySeverityLevel, std::string> m_log;
boost::shared_ptr<bl::sinks::sink> m_sink;
const std::string m_channel;
const MySeverityLevel m_severityMax;
};
int main()
{
Logger lgA("A", MySeverityLevel::error);
lgA.panic("A: Panic");
lgA.debug("A: Debug");
lgA.terminate();
}
Это вывод valgrind:
hekto@ubuntu:~$ valgrind --leak-check=full --show-leak-kinds=all ./tc0013
==48934== Memcheck, a memory error detector
==48934== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==48934== Using Valgrind-3.13.0 and LibVEX; rerun with -h for copyright info
==48934== Command: ./tc0013
==48934==
==48934==
==48934== HEAP SUMMARY:
==48934== in use at exit: 520 bytes in 6 blocks
==48934== total heap usage: 83 allocs, 77 frees, 97,276 bytes allocated
==48934==
==48934== 8 bytes in 1 blocks are still reachable in loss record 1 of 6
==48934== at 0x4C3017F: operator new(unsigned long) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==48934== by 0x4E98C61: boost::log::v2_mt_posix::sources::aux::get_severity_level() (in /usr/lib/x86_64-linux-gnu/libboost_log.so.1.65.1)
==48934== by 0x11723B: boost::log::v2_mt_posix::sources::aux::severity_level<MySeverityLevel>::set_value(MySeverityLevel) (severity_feature.hpp:135)
==48934== by 0x115E74: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_severity_logger<boost::log::v2_mt_posix::sources::basic_channel_logger<boost::log::v2_mt_posix::sources::basic_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MySeverityLevel>::open_record_unlocked<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (severity_feature.hpp:252)
==48934== by 0x114961: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_composite_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model, boost::log::v2_mt_posix::sources::features<boost::log::v2_mt_posix::sources::severity<MySeverityLevel>, boost::log::v2_mt_posix::sources::channel<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >::open_record<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (basic_logger.hpp:575)
==48934== by 0x1135A5: Logger::panic(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (tc0013.cpp:81)
==48934== by 0x11097B: main (tc0013.cpp:120)
==48934==
==48934== 8 bytes in 1 blocks are still reachable in loss record 2 of 6
==48934== at 0x4C3017F: operator new(unsigned long) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==48934== by 0x4E9EF69: boost::log::v2_mt_posix::aux::this_thread::get_id() (in /usr/lib/x86_64-linux-gnu/libboost_log.so.1.65.1)
==48934== by 0x4E8BB96: boost::log::v2_mt_posix::core::open_record(boost::log::v2_mt_posix::attribute_set const&) (in /usr/lib/x86_64-linux-gnu/libboost_log.so.1.65.1)
==48934== by 0x118DEA: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model>::open_record_unlocked<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (basic_logger.hpp:259)
==48934== by 0x11825B: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_channel_logger<boost::log::v2_mt_posix::sources::basic_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >::open_record_with_channel_unlocked<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&, boost::parameter::void_) (channel_feature.hpp:195)
==48934== by 0x1172B2: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_channel_logger<boost::log::v2_mt_posix::sources::basic_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >::open_record_unlocked<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (channel_feature.hpp:171)
==48934== by 0x115E8B: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_severity_logger<boost::log::v2_mt_posix::sources::basic_channel_logger<boost::log::v2_mt_posix::sources::basic_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MySeverityLevel>::open_record_unlocked<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (severity_feature.hpp:253)
==48934== by 0x114961: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_composite_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model, boost::log::v2_mt_posix::sources::features<boost::log::v2_mt_posix::sources::severity<MySeverityLevel>, boost::log::v2_mt_posix::sources::channel<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >::open_record<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (basic_logger.hpp:575)
==48934== by 0x1135A5: Logger::panic(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (tc0013.cpp:81)
==48934== by 0x11097B: main (tc0013.cpp:120)
==48934==
==48934== 16 bytes in 1 blocks are still reachable in loss record 3 of 6
==48934== at 0x4C3017F: operator new(unsigned long) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==48934== by 0x512A5BA: boost::detail::add_thread_exit_function(boost::detail::thread_exit_function_base*) (in /usr/lib/x86_64-linux-gnu/libboost_thread.so.1.65.1)
==48934== by 0x4E98C9A: boost::log::v2_mt_posix::sources::aux::get_severity_level() (in /usr/lib/x86_64-linux-gnu/libboost_log.so.1.65.1)
==48934== by 0x11723B: boost::log::v2_mt_posix::sources::aux::severity_level<MySeverityLevel>::set_value(MySeverityLevel) (severity_feature.hpp:135)
==48934== by 0x115E74: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_severity_logger<boost::log::v2_mt_posix::sources::basic_channel_logger<boost::log::v2_mt_posix::sources::basic_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MySeverityLevel>::open_record_unlocked<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (severity_feature.hpp:252)
==48934== by 0x114961: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_composite_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model, boost::log::v2_mt_posix::sources::features<boost::log::v2_mt_posix::sources::severity<MySeverityLevel>, boost::log::v2_mt_posix::sources::channel<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >::open_record<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (basic_logger.hpp:575)
==48934== by 0x1135A5: Logger::panic(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (tc0013.cpp:81)
==48934== by 0x11097B: main (tc0013.cpp:120)
==48934==
==48934== 24 bytes in 1 blocks are still reachable in loss record 4 of 6
==48934== at 0x4C3017F: operator new(unsigned long) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==48934== by 0x4E98C84: boost::log::v2_mt_posix::sources::aux::get_severity_level() (in /usr/lib/x86_64-linux-gnu/libboost_log.so.1.65.1)
==48934== by 0x11723B: boost::log::v2_mt_posix::sources::aux::severity_level<MySeverityLevel>::set_value(MySeverityLevel) (severity_feature.hpp:135)
==48934== by 0x115E74: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_severity_logger<boost::log::v2_mt_posix::sources::basic_channel_logger<boost::log::v2_mt_posix::sources::basic_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MySeverityLevel>::open_record_unlocked<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (severity_feature.hpp:252)
==48934== by 0x114961: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_composite_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model, boost::log::v2_mt_posix::sources::features<boost::log::v2_mt_posix::sources::severity<MySeverityLevel>, boost::log::v2_mt_posix::sources::channel<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >::open_record<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (basic_logger.hpp:575)
==48934== by 0x1135A5: Logger::panic(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (tc0013.cpp:81)
==48934== by 0x11097B: main (tc0013.cpp:120)
==48934==
==48934== 24 bytes in 1 blocks are still reachable in loss record 5 of 6
==48934== at 0x4C3017F: operator new(unsigned long) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==48934== by 0x512A1BC: boost::detail::make_external_thread_data() (in /usr/lib/x86_64-linux-gnu/libboost_thread.so.1.65.1)
==48934== by 0x512A5AD: boost::detail::add_thread_exit_function(boost::detail::thread_exit_function_base*) (in /usr/lib/x86_64-linux-gnu/libboost_thread.so.1.65.1)
==48934== by 0x4E98C9A: boost::log::v2_mt_posix::sources::aux::get_severity_level() (in /usr/lib/x86_64-linux-gnu/libboost_log.so.1.65.1)
==48934== by 0x11723B: boost::log::v2_mt_posix::sources::aux::severity_level<MySeverityLevel>::set_value(MySeverityLevel) (severity_feature.hpp:135)
==48934== by 0x115E74: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_severity_logger<boost::log::v2_mt_posix::sources::basic_channel_logger<boost::log::v2_mt_posix::sources::basic_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MySeverityLevel>::open_record_unlocked<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (severity_feature.hpp:252)
==48934== by 0x114961: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_composite_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model, boost::log::v2_mt_posix::sources::features<boost::log::v2_mt_posix::sources::severity<MySeverityLevel>, boost::log::v2_mt_posix::sources::channel<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >::open_record<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (basic_logger.hpp:575)
==48934== by 0x1135A5: Logger::panic(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (tc0013.cpp:81)
==48934== by 0x11097B: main (tc0013.cpp:120)
==48934==
==48934== 440 bytes in 1 blocks are still reachable in loss record 6 of 6
==48934== at 0x4C3017F: operator new(unsigned long) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==48934== by 0x512A03D: boost::detail::make_external_thread_data() (in /usr/lib/x86_64-linux-gnu/libboost_thread.so.1.65.1)
==48934== by 0x512A5AD: boost::detail::add_thread_exit_function(boost::detail::thread_exit_function_base*) (in /usr/lib/x86_64-linux-gnu/libboost_thread.so.1.65.1)
==48934== by 0x4E98C9A: boost::log::v2_mt_posix::sources::aux::get_severity_level() (in /usr/lib/x86_64-linux-gnu/libboost_log.so.1.65.1)
==48934== by 0x11723B: boost::log::v2_mt_posix::sources::aux::severity_level<MySeverityLevel>::set_value(MySeverityLevel) (severity_feature.hpp:135)
==48934== by 0x115E74: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_severity_logger<boost::log::v2_mt_posix::sources::basic_channel_logger<boost::log::v2_mt_posix::sources::basic_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MySeverityLevel>::open_record_unlocked<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (severity_feature.hpp:252)
==48934== by 0x114961: boost::log::v2_mt_posix::record boost::log::v2_mt_posix::sources::basic_composite_logger<char, boost::log::v2_mt_posix::sources::severity_channel_logger<MySeverityLevel, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::log::v2_mt_posix::sources::single_thread_model, boost::log::v2_mt_posix::sources::features<boost::log::v2_mt_posix::sources::severity<MySeverityLevel>, boost::log::v2_mt_posix::sources::channel<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >::open_record<boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> >(boost::parameter::aux::tagged_argument<boost::log::v2_mt_posix::keywords::tag::severity, MySeverityLevel const> const&) (basic_logger.hpp:575)
==48934== by 0x1135A5: Logger::panic(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (tc0013.cpp:81)
==48934== by 0x11097B: main (tc0013.cpp:120)
==48934==
==48934== LEAK SUMMARY:
==48934== definitely lost: 0 bytes in 0 blocks
==48934== indirectly lost: 0 bytes in 0 blocks
==48934== possibly lost: 0 bytes in 0 blocks
==48934== still reachable: 520 bytes in 6 blocks
==48934== suppressed: 0 bytes in 0 blocks
==48934==
==48934== For counts of detected and suppressed errors, rerun with: -v
==48934== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
В моем реальном приложении класс Logger находится в библиотеке, поэтому мне нужно правильно его завершить (завершение выполняется systemctl). Однако я все еще вижу исключения в syslog при выходе из моего приложения:
terminate called after throwing an instance of 'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::log::v2_mt_posix::system_error> >'
Я думаю, что поиск способа избавиться от этих «520 байтов в 6 блоках» после выхода поможет мне однозначно завершить мое приложение.
Как правильно написать функцию terminate (см. Выше) - чтобы нет оставил что-либо во внутренностях Boost Log доступным?





tl; dr; boost.log безнадежно обречен, используйте что-нибудь другое ...
Особенностью этих стеков вызовов является повторный вызов boost::detail::add_thread_exit_function, который является реализацией boost::this_thread::at_thread_exit, который, очевидно, используется для выполнения некоторых действий по очистке, когда поток приближается к завершению. Однако эту функцию нельзя использовать с системными API-интерфейсами и функциями завершения потока, такими как exit. Как указано в документах:
In particular, returning from main() is equivalent to call to exit(), so will not call any functions registered with at_thread_exit()
Таким образом, boost.log не выполняет никакой очистки при вызове из основного потока. Более того, (среди прочего) boost.log использует синглтон Мейера для хранения экземпляра основного контекста, поэтому пользователи библиотеки не могут контролировать время жизни основного контекста (и принадлежащих ему объектов) и склонны к статическому [не] порядку инициализации. фиаско.
Спасибо! Итак, синглтон в разделяемой библиотеке - зло ... Я задал вопрос о контексте MongoDB (stackoverflow.com/questions/50914898/…) в прошлом году, и ведущий инженер MongoDB порекомендовал мне использовать именно его - синглтон Мейера в разделяемой библиотеке (github.com/mongodb/mongo-cxx-driver/blob/r3.3.0/examples/…) . Не могли бы вы это прокомментировать? (Намного короче)))
@HEKTO Дело не в том, что синглтон - это зло, а в том, что он [не] инициализируется неявно без контроля над временем жизни объекта со стороны программиста. Думаю, от некоторых минимальных примеров многого ожидать не стоит. Еще один несколько связанный вопрос с интересным обсуждением: Форсировать создание глобального объекта
@VTT - готово, спасибо