strace/gcc_compat.h
Dmitry V. Levin f12aa97aab xlat: check that system definitions match fallback definitions
For each constant that is accompanied by a fallback definition,
generate a sanity check that the definition provided by system headers
matches the fallback definition.

* gcc_compat.h (DIAG_PUSH_IGNORE_TAUTOLOGICAL_COMPARE,
DIAG_POP_IGNORE_TAUTOLOGICAL_COMPARE): New macros.
* xlat/gen.sh (cond_def): Generate a code that checks the system
definition against the default.
(gen_header): Generate a code that includes "gcc_compat.h" and
"static_assert.h".

Co-Authored-by: Eugene Syromyatnikov <evgsyr@gmail.com>
2018-04-29 21:59:55 +00:00

114 lines
3.9 KiB
C

/*
* Copyright (c) 2015 Dmitry V. Levin <ldv@altlinux.org>
* Copyright (c) 2015-2018 The strace developers.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef STRACE_GCC_COMPAT_H
#define STRACE_GCC_COMPAT_H
#if defined __GNUC__ && defined __GNUC_MINOR__
# define GNUC_PREREQ(maj, min) \
((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
#else
# define __attribute__(x) /* empty */
# define GNUC_PREREQ(maj, min) 0
#endif
#if GNUC_PREREQ(2, 5)
# define ATTRIBUTE_NORETURN __attribute__((__noreturn__))
#else
# define ATTRIBUTE_NORETURN /* empty */
#endif
#if GNUC_PREREQ(2, 7)
# define ATTRIBUTE_FORMAT(args) __attribute__((__format__ args))
# define ATTRIBUTE_ALIGNED(arg) __attribute__((__aligned__(arg)))
# define ATTRIBUTE_PACKED __attribute__((__packed__))
#else
# define ATTRIBUTE_FORMAT(args) /* empty */
# define ATTRIBUTE_ALIGNED(arg) /* empty */
# define ATTRIBUTE_PACKED /* empty */
#endif
#if GNUC_PREREQ(3, 0)
# define SAME_TYPE(x, y) __builtin_types_compatible_p(typeof(x), typeof(y))
# define FAIL_BUILD_ON_ZERO(expr) (sizeof(int[-1 + 2 * !!(expr)]) * 0)
/* &(a)[0] is a pointer and not an array, shouldn't be treated as the same */
# define MUST_BE_ARRAY(a) FAIL_BUILD_ON_ZERO(!SAME_TYPE((a), &(a)[0]))
#else
# define SAME_TYPE(x, y) 0
# define MUST_BE_ARRAY(a) 0
#endif
#if GNUC_PREREQ(3, 0)
# define ATTRIBUTE_MALLOC __attribute__((__malloc__))
#else
# define ATTRIBUTE_MALLOC /* empty */
#endif
#if GNUC_PREREQ(3, 1)
# define ATTRIBUTE_NOINLINE __attribute__((__noinline__))
#else
# define ATTRIBUTE_NOINLINE /* empty */
#endif
#if GNUC_PREREQ(4, 0)
# define ATTRIBUTE_SENTINEL __attribute__((__sentinel__))
#else
# define ATTRIBUTE_SENTINEL /* empty */
#endif
#if GNUC_PREREQ(4, 1)
# define ALIGNOF(t_) __alignof__(t_)
#else
# define ALIGNOF(t_) (sizeof(struct { char x_; t_ y_; }) - sizeof(t_))
#endif
#if GNUC_PREREQ(4, 3)
# define ATTRIBUTE_ALLOC_SIZE(args) __attribute__((__alloc_size__ args))
#else
# define ATTRIBUTE_ALLOC_SIZE(args) /* empty */
#endif
#if GNUC_PREREQ(7, 0)
# define ATTRIBUTE_FALLTHROUGH __attribute__((__fallthrough__))
#else
# define ATTRIBUTE_FALLTHROUGH ((void) 0)
#endif
#if GNUC_PREREQ(6, 0)
# define DIAG_PUSH_IGNORE_TAUTOLOGICAL_COMPARE \
_Pragma("GCC diagnostic push"); \
_Pragma("GCC diagnostic ignored \"-Wtautological-compare\"");
# define DIAG_POP_IGNORE_TAUTOLOGICAL_COMPARE \
_Pragma("GCC diagnostic pop");
#else
# define DIAG_PUSH_IGNORE_TAUTOLOGICAL_COMPARE /* empty */
# define DIAG_POP_IGNORE_TAUTOLOGICAL_COMPARE /* empty */
#endif
#endif /* !STRACE_GCC_COMPAT_H */