[Bug libstdc++/96279] build failure: floating_from_chars.cc:310:22: error: '__builtin_isinf_sign' is not a member of 'std'

[zsojka at seznam dot cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96279

--- Comment #4 from Zdenek Sojka <zsojka at seznam dot cz> ---
I can no longer reproduce this: r11-2420 (BAD), r11-2449 (OK)