/* Test for NaN that does not need libm. Copyright (C) 2007-2023 Free Software Foundation, Inc. This file is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This file is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this program. If not, see . */ /* This file uses HAVE_ISNANL_IN_LIBC. */ #if !_GL_CONFIG_H_INCLUDED #error "Please include config.h first." #endif #if HAVE_ISNANL_IN_LIBC /* Get declaration of isnan macro or (older) isnanl function. */ # include # if (__GNUC__ >= 4) || (__clang_major__ >= 4) /* GCC >= 4.0 and clang provide a type-generic built-in for isnan. GCC >= 4.0 also provides __builtin_isnanl, but clang doesn't. */ # undef isnanl # define isnanl(x) __builtin_isnan ((long double)(x)) # elif defined isnan # undef isnanl # define isnanl(x) isnan ((long double)(x)) # endif #else /* Test whether X is a NaN. */ # undef isnanl # define isnanl rpl_isnanl extern int isnanl (long double x); #endif