80d50c5665
* tools/snippet/_Noreturn.h, tools/snippet/c++defs.h, tools/snippet/arg-nonnull.h, tools/snippet/warn-on-use.h: Rename to... * lib/_Noreturn.h, lib/c++defs.h, lib/arg-nonnull.h, lib/warn-on-use.h: ... these. * lib/filename.h, lib/getopt-cdefs.in.h, lib/getopt-core.h, lib/getopt-ext.h, lib/getopt-pfx-core.h, lib/getopt-pfx-ext.h, lib/localtime-buffer.c, lib/localtime-buffer.h, lib/malloca.c, lib/malloca.h, lib/malloca.valgrind, lib/stat-w32.c, lib/stat-w32.h, m4/eealloc.m4, m4/localtime-buffer.m4, m4/malloca.m4: New files. * lib/argp-help.c, lib/argp-parse.c, lib/error.c, lib/float.in.h, lib/getopt1.c, lib/getopt.c, lib/getopt.in.h, lib/getopt_int.h, lib/gettext.h, lib/gettimeofday.c, lib/intprops.h, lib/isatty.c, lib/limits.in.h, lib/localcharset.c, lib/Makefile.am, lib/mbrtowc.c, lib/mbsinit.c, lib/msvc-nothrow.c, lib/quotearg.c, lib/stat.c, lib/stdalign.in.h, lib/stdint.in.h, lib/string.in.h, lib/sys_stat.in.h, lib/sys_types.in.h, lib/tempname.c, lib/time.in.h, lib/unistd.in.h, lib/vasnprintf.c, lib/wchar.in.h, lib/wctype.in.h, lib/xalloc.h, lib/xalloc-oversized.h, m4/fcntl-o.m4, m4/float_h.m4, m4/getopt.m4, m4/gettimeofday.m4, m4/gnulib-common.m4, m4/gnulib-comp.m4, m4/include_next.m4, m4/largefile.m4, m4/lstat.m4, m4/mbrtowc.m4, m4/memchr.m4, m4/mkstemp.m4, m4/printf.m4, m4/sleep.m4, m4/stat.m4, m4/stdalign.m4, m4/stdint.m4, m4/strerror.m4, m4/string_h.m4, m4/sys_stat_h.m4, m4/sys_time_h.m4, m4/sys_types_h.m4, m4/time_h.m4, m4/unistd_h.m4, m4/wchar_h.m4, m4/wctype_h.m4, m4/wint_t.m4: Update.
121 lines
4.6 KiB
C++
121 lines
4.6 KiB
C++
/* A substitute for ISO C11 <stdalign.h>.
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Copyright 2011-2017 Free Software Foundation, Inc.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3, or (at your option)
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any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, see <http://www.gnu.org/licenses/>. */
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/* Written by Paul Eggert and Bruno Haible. */
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#ifndef _GL_STDALIGN_H
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#define _GL_STDALIGN_H
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/* ISO C11 <stdalign.h> for platforms that lack it.
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References:
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ISO C11 (latest free draft
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<http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf>)
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sections 6.5.3.4, 6.7.5, 7.15.
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C++11 (latest free draft
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<http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3242.pdf>)
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section 18.10. */
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/* alignof (TYPE), also known as _Alignof (TYPE), yields the alignment
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requirement of a structure member (i.e., slot or field) that is of
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type TYPE, as an integer constant expression.
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This differs from GCC's __alignof__ operator, which can yield a
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better-performing alignment for an object of that type. For
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example, on x86 with GCC, __alignof__ (double) and __alignof__
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(long long) are 8, whereas alignof (double) and alignof (long long)
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are 4 unless the option '-malign-double' is used.
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The result cannot be used as a value for an 'enum' constant, if you
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want to be portable to HP-UX 10.20 cc and AIX 3.2.5 xlc.
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Include <stddef.h> for offsetof. */
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#include <stddef.h>
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/* FreeBSD 9.1 <sys/cdefs.h>, included by <stddef.h> and lots of other
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standard headers, defines conflicting implementations of _Alignas
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and _Alignof that are no better than ours; override them. */
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#undef _Alignas
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#undef _Alignof
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/* GCC releases before GCC 4.9 had a bug in _Alignof. See GCC bug 52023
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<http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52023>. */
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#if (!defined __STDC_VERSION__ || __STDC_VERSION__ < 201112 \
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|| (defined __GNUC__ && __GNUC__ < 4 + (__GNUC_MINOR__ < 9)))
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# ifdef __cplusplus
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# if 201103 <= __cplusplus
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# define _Alignof(type) alignof (type)
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# else
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template <class __t> struct __alignof_helper { char __a; __t __b; };
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# define _Alignof(type) offsetof (__alignof_helper<type>, __b)
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# endif
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# else
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# define _Alignof(type) offsetof (struct { char __a; type __b; }, __b)
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# endif
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#endif
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#if ! (defined __cplusplus && 201103 <= __cplusplus)
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# define alignof _Alignof
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#endif
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#define __alignof_is_defined 1
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/* alignas (A), also known as _Alignas (A), aligns a variable or type
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to the alignment A, where A is an integer constant expression. For
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example:
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int alignas (8) foo;
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struct s { int a; int alignas (8) bar; };
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aligns the address of FOO and the offset of BAR to be multiples of 8.
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A should be a power of two that is at least the type's alignment
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and at most the implementation's alignment limit. This limit is
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2**28 on typical GNUish hosts, and 2**13 on MSVC. To be portable
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to MSVC through at least version 10.0, A should be an integer
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constant, as MSVC does not support expressions such as 1 << 3.
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To be portable to Sun C 5.11, do not align auto variables to
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anything stricter than their default alignment.
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The following C11 requirements are not supported here:
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- If A is zero, alignas has no effect.
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- alignas can be used multiple times; the strictest one wins.
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- alignas (TYPE) is equivalent to alignas (alignof (TYPE)).
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*/
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#if !defined __STDC_VERSION__ || __STDC_VERSION__ < 201112
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# if defined __cplusplus && 201103 <= __cplusplus
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# define _Alignas(a) alignas (a)
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# elif ((defined __APPLE__ && defined __MACH__ \
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? 4 < __GNUC__ + (1 <= __GNUC_MINOR__) \
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: __GNUC__) \
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|| (__ia64 && (61200 <= __HP_cc || 61200 <= __HP_aCC)) \
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|| __ICC || 0x590 <= __SUNPRO_C || 0x0600 <= __xlC__)
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# define _Alignas(a) __attribute__ ((__aligned__ (a)))
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# elif 1300 <= _MSC_VER
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# define _Alignas(a) __declspec (align (a))
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# endif
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#endif
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#if ((defined _Alignas && ! (defined __cplusplus && 201103 <= __cplusplus)) \
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|| (defined __STDC_VERSION__ && 201112 <= __STDC_VERSION__))
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# define alignas _Alignas
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#endif
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#if defined alignas || (defined __cplusplus && 201103 <= __cplusplus)
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# define __alignas_is_defined 1
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#endif
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#endif /* _GL_STDALIGN_H */
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