@node ilogbl
@section @code{ilogbl}
@findex ilogbl

POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9699919799/functions/ilogbl.html}

Gnulib module: ilogbl

Portability problems fixed by Gnulib:
@itemize
@item
This function is missing on some platforms:
FreeBSD 5.2.1, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 9, Cygwin 1.7.x, MSVC 9.
@item
This function returns a wrong result for a zero argument on some platforms:
@c https://cygwin.com/ml/cygwin/2019-12/msg00074.html
Cygwin 2.9.
@item
This function returns a wrong result for a NaN argument on some platforms:
@c https://cygwin.com/pipermail/cygwin/2023-April/253511.html
Cygwin 3.4.6.
@item
This function returns a wrong result for denormalized arguments on some platforms:
AIX 7.1 64-bit, Haiku 2017.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@end itemize