The docs says that you can configure libstdc++ with --enable-clocale=ieee_1003.1-2001. However, this fails in mainline because _GLIBCXX_NUM_CATEGORIES is only defined for the generic and gnu locales.
See http://gcc.gnu.org/ml/libstdc++/2009-09/msg00091.html . -- Summary: libstdc++ --enable-clocale=ieee_1003.1-2001 fails Product: gcc Version: 4.5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: ian at airs dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41495
