[Bug libstdc++/68737] FAIL: 22_locale/num_put/put/char/14220.cc execution test

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68737

--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I assume the implementation in libstdc++-v3/config/locale/generic/c_locale.h is
used for HPUX, so one of these is returning an error, which we then use as
__len:

#if _GLIBCXX_USE_C99_STDIO
    const int __ret = __builtin_vsnprintf(__out, __size, __fmt, __args);
#else
    const int __ret = __builtin_vsprintf(__out, __fmt, __args);
#endif