1 /* ABI compatibility for lgamma functions. 2 Copyright (C) 2015-2022 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 as 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 #ifndef LGAMMA_COMPAT_H 20 #define LGAMMA_COMPAT_H 1 21 22 #include <math-svid-compat.h> 23 #include <shlib-compat.h> 24 25 /* XSI POSIX requires lgamma to set signgam, but ISO C does not permit 26 this. Namespace issues can be avoided if the functions set 27 __signgam and signgam is a weak alias, but this only works if both 28 signgam and __signgam were exported from the glibc version the 29 program was linked against. Before glibc 2.23, lgamma functions 30 set signgam which was not a weak alias for __signgam, so old 31 binaries have dynamic symbols for signgam only and the versions of 32 lgamma used for old binaries must set both signgam and __signgam. 33 Those versions also do a check of _LIB_VERSION != _ISOC_ to match 34 old glibc. 35 36 Users of this file define USE_AS_COMPAT to 0 when building the main 37 version of lgamma, 1 when building the compatibility version. */ 38 39 #define LGAMMA_OLD_VER GLIBC_2_0 40 #define LGAMMA_NEW_VER GLIBC_2_23 41 #define HAVE_LGAMMA_COMPAT SHLIB_COMPAT (libm, LGAMMA_OLD_VER, LGAMMA_NEW_VER) 42 43 /* Whether to build this version at all. */ 44 #define BUILD_LGAMMA \ 45 (LIBM_SVID_COMPAT && (HAVE_LGAMMA_COMPAT || !USE_AS_COMPAT)) 46 47 /* The name to use for this version. */ 48 #if USE_AS_COMPAT 49 # define LGFUNC(FUNC) FUNC ## _compat 50 #else 51 # define LGFUNC(FUNC) FUNC 52 #endif 53 54 /* If there is a compatibility version, gamma (not an ISO C function, 55 so never a problem for it to set signgam) points directly to it 56 rather than having separate versions. */ 57 #define GAMMA_ALIAS (USE_AS_COMPAT ? HAVE_LGAMMA_COMPAT : !HAVE_LGAMMA_COMPAT) 58 59 /* How to call the underlying lgamma_r function. */ 60 #define CALL_LGAMMA(TYPE, FUNC, ARG) \ 61 ({ \ 62 TYPE lgamma_tmp; \ 63 int local_signgam; \ 64 if (USE_AS_COMPAT) \ 65 { \ 66 lgamma_tmp = FUNC ((ARG), &local_signgam); \ 67 if (_LIB_VERSION != _ISOC_) \ 68 signgam = __signgam = local_signgam; \ 69 } \ 70 else \ 71 lgamma_tmp = FUNC ((ARG), &__signgam); \ 72 lgamma_tmp; \ 73 }) 74 75 #endif /* lgamma-compat.h. */ 76