Re: libstdc++/7445: poor performance of std::locale::classic() in multi-threaded applications

[Benjamin Kosnik <bkoz@redhat.com>]

The following reply was made to PR libstdc++/7445; it has been noted by GNATS.

From: Benjamin Kosnik <bkoz@redhat.com>
To: Loren James Rittle <rittle@latour.rsch.comm.mot.com>
Cc: bkoz@gcc.gnu.org, gcc-bugs@gcc.gnu.org, gcc-gnats@gcc.gnu.org,
   gcc-prs@gcc.gnu.org, ljrittle@gcc.gnu.org, shurik@sequoiap.com
Subject: Re: libstdc++/7445: poor performance of std::locale::classic() in multi-threaded applications
Date: Thu, 8 Aug 2002 23:18:57 -0700

 > OK, I'd be happy to find a performance fix that doesn't make the
 > library code subtly less portable when we have a test case.  A
 > reference to code already in our test suite would be acceptable.
 
 Yeah. This is kind of all hand-wavy at this point.
 
 > Benjamin (as the "local locale" expert), is it *always* true that
 > std::locale::classic() is called at least once during startup before
 > control is transferred to main()?  If so (and will always be so), then
 > all thread-related locking could be removed IMHO.  In practice, our
 > implementation of the Standard C++ library (with optional threading
 > support) already supposes that no thread which uses the library
 > implementation may have ever been started before main() is invoked.
 > If not true, then this change would make a very hard to detect
 > threading bug when the assumption changes.
 
 This is true. I would think the lock could then be removed? I'll let you
 figure out what to do with current sources. Thanks for the help.
 
 -benjamin