Localization with libstdc++ fails on FreeBSD

[Sashi Asokarajan <sashi at gmx dot de>]

Hello,

if I try to instantiate std::locale for locales other than "C",
it aborts with an exception in FreeBSD 7.0 !
What I found out so far is, that FreeBSD is probably configured with the darwin
locale model. There is a configure option named --enable-clocale for libstdc++,
which is used to set the locale model.

The default (option omitted) is to autodetect for the target_os.
The automatic locale detection in the libstdc++ configure script says following:
   5801   # Probe for locale model to use if none specified.
   5802   # Default to "generic".
   5803   if test $enable_clocale_flag = auto; then
   5804     case ${target_os} in
   5805       linux* | gnu* | kfreebsd*-gnu | knetbsd*-gnu)
   5806         enable_clocale_flag=gnu
   5807         ;;
   5808       darwin* | freebsd*)
   5809         enable_clocale_flag=darwin
   5810         ;;
   5811       *)
   5812         enable_clocale_flag=generic
   5813         ;;
   5814     esac
   5815   fi

My GCC reports:
> gcc -v
Using built-in specs.
Target: i386-undermydesk-freebsd
Configured with: FreeBSD/i386 system compiler
Thread model: posix
gcc version 4.2.1 20070719  [FreeBSD]

on my FreeBSD 7.0-RELEASE system.

My $LANG is set to de_DE.UTF-8 (via login.conf).
locale -a|grep de_DE reports:
de_DE.ISO8859-1
de_DE.ISO8859-15
de_DE.UTF-8

Here's a C++ code you may want to try (compile with CC <filename.cc>).
It works well with "setenv LANG C", but fails if LANG=de_DE.UTF-8 (or any other) !
//---------------------------------------------------
#include <locale>
#include <iostream>
#include <clocale>

int main()
{
 using std::cout;
 using std::endl;

 // C L10n
 const char* const lstr = std::setlocale(LC_ALL, "");
 cout << "C setlocale()\nresult=";
 cout << ( lstr ? lstr : "0" ) << "\n" << endl;

 // C++ L10n
 cout << "C++ std::locale" << endl;
 std::locale loc("");
 cout << "std::locale loc=" << loc.name() << endl;
}
//---------------------------------------------------


Output (set $LANG to de_DE.UTF-8 and run with ./a.out):
-------------------------------------------------------------------
C setlocale()
result=de_DE.UTF-8

C++ std::locale
terminate called after throwing an instance of 'std::runtime_error'
  what():  locale::facet::_S_create_c_locale name not valid
Abort (core dumped)
-------------------------------------------------------------------


Why does the "darwin" (which is generic) model apply to the FreeBSD OS?
(I guess C++ localization will also fail on MacOS X too.)

Thanks in advance for any ideas.


--
Sashi Asokarajan