https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123987
--- Comment #3 from lukewang <314575546 at qq dot com> --- https://man7.org/linux/man-pages/man3/finite.3.html The isinf(), isinff(), and isinfl() functions return 1 if x is positive infinity, -1 if x is negative infinity, and 0 otherwise. Why is this behavior inconsistent with that in the Linux manual?
