long-double.h (2339B) - Raw
1 /* Properties of long double type. 2 Copyright (C) 2016-2025 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19 /* This header is included by <sys/cdefs.h>. 20 21 If long double is ABI-compatible with double, it should define 22 __NO_LONG_DOUBLE_MATH to 1; otherwise, it should leave 23 __NO_LONG_DOUBLE_MATH undefined. 24 25 If this build of the GNU C Library supports both long double 26 ABI-compatible with double and some other long double format not 27 ABI-compatible with double, it should define 28 __LONG_DOUBLE_MATH_OPTIONAL to 1; otherwise, it should leave 29 __LONG_DOUBLE_MATH_OPTIONAL undefined. 30 31 If __NO_LONG_DOUBLE_MATH is already defined, this header must not 32 define anything; this is needed to work with the definition of 33 __NO_LONG_DOUBLE_MATH in nldbl-compat.h. */ 34 35 /* In the default version of this header, long double is 36 ABI-compatible with double. */ 37 #ifndef __NO_LONG_DOUBLE_MATH 38 # define __NO_LONG_DOUBLE_MATH 1 39 #endif 40 41 /* The macro __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI is used to determine the 42 choice of the underlying ABI of long double. It will always assume 43 a constant value for each translation unit. 44 45 If the value is non-zero, any API which is parameterized by the long 46 double type (i.e the scanf/printf family of functions or the explicitly 47 parameterized math.h functions) will be redirected to a compatible 48 implementation using _Float128 ABI via symbols suffixed with ieee128. 49 50 The mechanism this macro uses to acquire may be a function 51 of architecture, or target specific options used to invoke the 52 compiler. */ 53 #define __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI 0