Re: [v3] libstdc++/7811

[Paolo Carlini <pcarlini at unitus dot it>]

Jakub Jelinek wrote:

> > > For #ifndef _GLIBCPP_C_LOCALE_GNU you should do:
> > > old = strdup(setlocale(LC_ALL, NULL));
> > > ret = strdup(setlocale(LC_ALL, ""));
> > > setlocale(LC_ALL, old);
> > > free(old);
> > > or some such, for _GLIBCPP_C_LOCALE_GNU maybe "" should be passed directly
> > > to _Impl constructor...
> > ... as Roland McGrath explained to me privately setlocale(LC_ALL, "") 
> > *cannot* be used in a MT environment.
> >    
> That's true, but without uselocale you basically have no other option.
> Even when you have some _l routines, lots of others are still missing.
I see, but I don't think we can afford the risk of crashes in a MT 
environment only for this kind of QoI issue in the inizialization from 
the environment.
On the other hand...

> So IMHO at least with glibc 2.3+ we should DTRT (provided that we allow
> libstdc++-v3 to use __names[] members of struct __locale_struct), which
> is pass "" as locale name down to _Impl down to _S_create_locale in that
> case and if we really need accurate _M_names, set them
> from __cloc->__names[x].
... this is an interesting, indeed, but much more complex and invasive 
proposal. If you can work out a patch I think Benjamin would be happy to 
review it! ;-)

Benjamin, what do you believe?

Paolo.