On Sat, 4 Feb 2023, 13:12 François Dumont via Libstdc++, < libstd...@gcc.gnu.org> wrote:
> On 03/02/23 15:50, Jonathan Wakely wrote: > > On Wed, 25 Jan 2023 at 18:38, François Dumont <frs.dum...@gmail.com> > wrote: > >> Let's submit a proper patch proposal then. > >> > >> The occasion for me to ask if there is any reason for cow string not > >> being C++11 allocator compliant ? Just lack of interest ? > > Mostly lack of interest, but also I don't really want to "encourage" > > the use of the old string by investing lots of maintenance effort into > > it. If you want new features like C++11 Allocators and > > resize_and_overwrite etc then you should use the new type. > > > > I don't remember if there were any actual blockers that made it > > difficult to support stateful allocators in the COW string. I might > > have written something about it in mails to the list when I was adding > > the SSO string, but I don't remember now. > > Ok, thanks for feedback. I won't bother then. > > > > > Anyway, for this patch ... > > > >> I wanted to consider it to get rid of the __gnu_debug::_Safe_container > >> _IsCxx11AllocatorAware template parameter. > >> > >> libstdc++: Optimize basic_string move assignment > >> > >> Since resolution of Issue 2593 [1] we can consider that equal > >> allocators > >> before the propagate-on-move-assignment operations will still be > equal > >> afterward. > >> > >> So we can extend the optimization of transfering the storage of > the > >> move-to > >> instance to the move-from one that is currently limited to always > equal > >> allocators. > >> > >> [1] https://cplusplus.github.io/LWG/issue2593 > >> > >> libstdc++-v3/ChangeLog: > >> > >> * include/bits/basic_string.h (operator=(basic_string&&)): > >> Transfer move-to > >> storage to the move-from instance when allocators are > equal. > >> * > >> testsuite/21_strings/basic_string/allocator/char/move_assign.cc > (test04): > >> New test case. > >> > >> Tested under linux x86_64, ok to commit ? > > OK for trunk, thanks! > > > > +Reviewed-by: Jonathan Wakely <jwak...@redhat.com> > > Should I have added this to the commit ? > > If so sorry, I haven't. > No problem! I think it would be a good habit for us to all start doing that (copying the glibc project), to thank people who take the time to do a review. I don't really mind if my name gets recorded as reviewer, but I'm going to try to remember to add Reviewed-by: when I review something. And that might encourage others to do the same, and to do more reviewing :-) >
