/* MPFR internal header related to Static Assertions Copyright 2012-2023 Free Software Foundation, Inc. Contributed by the AriC and Caramba projects, INRIA. This file is part of the GNU MPFR Library. The GNU MPFR Library 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 3 of the License, or (at your option) any later version. The GNU MPFR Library 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 the GNU MPFR Library; see the file COPYING.LESSER. If not, see https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ #ifndef __MPFR_STATIC_ASSERT_H__ #define __MPFR_STATIC_ASSERT_H__ #include "mpfr-cvers.h" /* for __MPFR_GNUC */ /* How to use: =========== MPFR_STAT_STATIC_ASSERT: + to check a condition at compile time within the statement section. Note: In case one would need a static assertion in an expression, a sizeof(...) instead of a typedef could be used. For instance, see https://stackoverflow.com/questions/9229601/what-is-in-c-code (about BUILD_BUG_ON_ZERO in the Linux kernel). */ #ifdef MPFR_USE_STATIC_ASSERT /* C11 version */ # if defined (__STDC_VERSION__) # if (__STDC_VERSION__ >= 201112L) # define MPFR_STAT_STATIC_ASSERT(c) _Static_assert((c), #c ) # endif # endif /* Default version which should be compatible with nearly all compilers */ # if !defined(MPFR_STAT_STATIC_ASSERT) # if __MPFR_GNUC(4,8) /* Get rid of annoying warnings "typedef '...' locally defined but not used" (new in GCC 4.8). Thanks to Jonathan Wakely for this solution: https://gcc.gnu.org/legacy-ml/gcc-help/2013-07/msg00142.html */ # define MPFR_TYPEDEF_UNUSED __attribute__ ((unused)) # else # define MPFR_TYPEDEF_UNUSED # endif # define MPFR_ASSERT_CAT(a,b) MPFR_ASSERT_CAT_(a,b) # define MPFR_ASSERT_CAT_(a,b) a ## b # define MPFR_STAT_STATIC_ASSERT(c) do { \ typedef enum { MPFR_ASSERT_CAT(MPFR_STATIC_ASSERT_CONST_,__LINE__) = !(c) } \ MPFR_ASSERT_CAT(MPFR_ASSERT_,__LINE__)[!!(c) ? 1 : -1] \ MPFR_TYPEDEF_UNUSED; } while (0) # endif #else /* No support: default to classic assertions */ # define MPFR_STAT_STATIC_ASSERT(c) MPFR_ASSERTN(c) #endif #endif |