[Bug libstdc++/38368] New: locale(const char* std_name) may create locale with broken facets

["tsyvarev at ispras dot ru" <gcc-bugzilla at gcc dot gnu dot org>]

Locale constructor locale(const char* std_name) may create locale with broken
facets.

When std_name looks like "CAT1=name1;...;CATN=nameN", categories for which name
is "C" may have members, which differ from ones in "C" locale.

e.g. decimal_point() in moneypunct<> facet returns '\0' while in "C" locale it
returns '.'.
Also thousands_sep() in numpunct<> returns '\0' while in "C" locale it returns
','.

Example:
[test.cpp]
#include <locale>
#include <iostream>
using namespace std;

int main()
{
    locale loc(locale("C"), "en_US", locale::collate);
    cout << "Name of locale is " << loc.name() << endl;
    locale loc_copy(loc.name().c_str());
    if(use_facet<moneypunct<char> >(loc_copy).decimal_point() == '\0')
        cout << "decimal_point() is '\\0'\n";
    return 0;
}

[tester@Fedore8 locale_create_from_name]$ g++ test.cpp && ./a.out
Name of locale is
LC_CTYPE=C;LC_NUMERIC=C;LC_TIME=C;LC_COLLATE=en_US;LC_MONETARY=C;LC_MESSAGES=C;LC_PAPER=C;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=C;LC_IDENTIFICATION=C
decimal_point() is '\0'
[tester@Fedore8 locale_create_from_name]$ g++ --version
g++ (GCC) 4.3.0 20080428 (Red Hat 4.3.0-8)
Copyright (C) 2008 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.


-- 
           Summary: locale(const char* std_name) may create locale with
                    broken facets
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: tsyvarev at ispras dot ru


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38368