Date: Sun, 29 Aug 2010 19:53:15 GMT From: Yuri Karaban <tech@askold.net> To: freebsd-gnats-submit@FreeBSD.org Subject: standards/150093: C++ std::locale support is broken Message-ID: <201008291953.o7TJrFgZ050171@www.freebsd.org> Resent-Message-ID: <201008292000.o7TK03IA035222@freefall.freebsd.org>
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>Number: 150093
>Category: standards
>Synopsis: C++ std::locale support is broken
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: freebsd-standards
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Sun Aug 29 20:00:02 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator: Yuri Karaban
>Release: 8.1-RELEASE
>Organization:
>Environment:
>Description:
Standard C++ library, libstdc++, compiled with "generic" locale support. So only "C" and "POSIX" locales are supported.
Setting any other locale will throw the runtime_error exception "locale::facet::_S_create_c_locale name not valid". Though locale name is valid and works with setlocale(3).
On Linux libstdc++ is using "gnu" locale configuration. Which takes use of newlocale(3)/uselocale(3)/freelocale(3)/... POSIX calls. FreeBSD does not support these calls so it is not possible to use "gnu" configuration.
Since C++ standard allow several locale instances to coexists simultaneously, it must be not possible to implement C++ locales in terms of setlocale(3).
There are two possible solutions:
1. Implement locale related functions in FreeBSD C Library. This option is preferred: supporting standard functions is always a plus and having these function it is possible to use existing locale model in libstdc++.
2. Implement custom locale support for FreeBSD in libstdc++. Advantage that standard C library would be untouched. But on the other hand, there are many disadvantages (to create libstdc++ locale model from scratch; difficult to implement in terms of setlocale, means use of some hacks with libc internals).
PS. Locale support is really important. C++ programs which use locale is unusable on FreeBSD and there is no workaround.
>How-To-Repeat:
Compile and run following C++ code:
#include <locale>
int main()
{
std::locale("en_US.UTF-8");
}
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted:
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