Re: [boost] thread safety in boost date time

From: Peter Dimov (pdimov_at_[hidden])
Date: 2005-03-08 07:48:00

Jeff Garland wrote:
> On Tue, 8 Mar 2005 11:34:15 +0200, Yitzhak Sapir wrote
>> Boost date_time apparently has a thread safety problem in linux in
>> that it calls localtime() in boost/date_time/time_clock.hpp and
>> related functions rather than localtime_r() and related functions.
>>  This is even though BOOST_HAS_PTHREADS is defined by configure in
>> user.hpp.
>
> That's true -- date_time doesn't do anything to ensure thread safety.
> I'm a little reluctant to protect these functions since the user can
> determine better if they need to take the associated performance hit.
> Of course this needs to be documented, which it isn't now.  Thoughts?

There is no performance hit associated with the _r functions, and the user 
is not necessarily in a position to insert locks around localtime calls, 
because he might be using date_time indirectly. In my opinion, every library 
must provide the basic thread-safety guarantee in its default configuration.