[Bug libstdc++/70493] std::setlocale("") throws exception

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70493

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |WONTFIX

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Libstdc++ has no idea why the locale name was invalid. When you use the empty
string "" it constructs a locale name from the environment and then calls
newlocale from the C library. newlocale returns (locale_t)0 and sets ENOENT,
which according to POSIX means "For any of the categories in category_mask, the
locale data is not available" (or for the GNU C library, "locale is not a
string pointer referring to a valid locale").

Unless libstdc++ is going to iteratively try creating a locale from each of the
LC_* environment variables to see which one failed, it can't really give you
any better information. That doesn't seem worth the effort (and increase in
code size), sorry.