view doc/posix-functions/exp2l.texi @ 40111:234fea508b0e

exp2l: Work around inaccurate implementation on NetBSD. * m4/exp2l.m4 (gl_FUNC_EXP2L): Add test for a certain accuracy. * doc/posix-functions/exp2l.texi: Mention the NetBSD bug.
author Bruno Haible <bruno@clisp.org>
date Sun, 20 Jan 2019 21:45:29 +0100
parents 0f6b0bb3cee9
children
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@node exp2l
@section @code{exp2l}
@findex exp2l

POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/exp2l.html}

Gnulib module: exp2l or exp2l-ieee

Portability problems fixed by either Gnulib module @code{exp2l} or @code{exp2l-ieee}:
@itemize
@item
This function is missing on some platforms:
FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, older IRIX 6.5, OSF/1 4.0, Solaris 9, Cygwin, MSVC 9, Interix 3.5, BeOS, Android 4.4.
@item
This function is not declared on some platforms:
IRIX 6.5.
@item
This function produces results which are accurate to only 16 digits on some
platforms:
NetBSD 8.0.
@end itemize

Portability problems fixed by Gnulib module @code{exp2l-ieee}:
@itemize
@item
This function returns a wrong value for a NaN argument on some platforms:
OpenBSD 4.9.
@item
This function returns a wrong value for a negative infinity argument on some platforms:
IRIX 6.5.
@end itemize

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