libstdc++/9580: basic_filebuf<> with custom traits_type fails to link

[peturr02@ru.is]

>Number:         9580
>Category:       libstdc++
>Synopsis:       basic_filebuf<> with custom traits_type fails to link
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Feb 05 10:36:01 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator:     peturr02@ru.is
>Release:        gcc-3.2.1
>Organization:
>Environment:
Red Hat Linux 8.0
>Description:
basic_filebuf<CharT, Traits> fails to link if CharT is any type other than char or wchar_t or if Traits is any type other than char_traits<CharT>.

I think the attached program is required to link and run, in particular it satisfies the requirements for Traits in 21.1.1, 27.1.2 and 27.8.1.1.
>How-To-Repeat:
See attachment.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
----gnatsweb-attachment----
Content-Type: text/plain; name="instbug.cc"
Content-Disposition: inline; filename="instbug.cc"

#include <fstream>
using namespace std;

class MyTraits : public char_traits<char>
{
};

int main()
{
	basic_filebuf<char, MyTraits> fb;
	return 0;
}