I wrote that code, so let me comment on it:
The setlocale() function returns the setting that was previously active (see the setlocale (3) man-page).
Unfortunately, there's no clear standard on the way locales are named. The man-page says:
"""
A locale name is typically of the form language[_territory][.codeset][@modifier], where language is an ISO 639 language code, territory is an ISO 3166 country code, and codeset is a character set
or encoding identifier like ISO-8859-1 or UTF-8. For a list of all supported locales, try "locale -a", cf. locale(1).
"""
"Germany_Germany" is clearly not a locale name that fits the above scheme.
If I do "locale -a" on my box, the "Germany_Germany" is not mentioned in the resulting list, so there's no surprise that the function call generates an error.
Note that you can set the locale without using setlocale(): all that is needed is an environment variable and that is, of course, not subject to any checks by setlocal().
I'd suggest to close this bug report as invalid.
Thanks.