blob: 23ad803dce0bee3933ea3fde0d8c51a378f5ca03 [file] [log] [blame] [edit]
/* gcc version specific checks */
#ifndef GCC_VERSION
#define GCC_VERSION (__GNUC__ * 10000 \
+ __GNUC_MINOR__ * 100 \
+ __GNUC_PATCHLEVEL__)
#endif
#if GCC_VERSION < 30200
# error Sorry, your compiler is too old - please upgrade it.
#endif
#if GCC_VERSION < 30300
# define __used __attribute__((__unused__))
#else
# define __used __attribute__((__used__))
#endif
#ifdef CONFIG_GCOV_KERNEL
# if GCC_VERSION < 30400
# error "GCOV profiling support for gcc versions below 3.4 not included"
# endif /* __GNUC_MINOR__ */
#endif /* CONFIG_GCOV_KERNEL */
#if GCC_VERSION >= 30400
#define __must_check __attribute__((warn_unused_result))
#endif
#if GCC_VERSION >= 40000
/* GCC 4.1.[01] miscompiles __weak */
#ifdef __KERNEL__
# if GCC_VERSION >= 40100 && GCC_VERSION <= 40101
# error Your version of gcc miscompiles the __weak directive
# endif
#endif
#define __used __attribute__((__used__))
#define __compiler_offsetof(a, b) \
__builtin_offsetof(a, b)
#if GCC_VERSION >= 40100 && GCC_VERSION < 40600
# define __compiletime_object_size(obj) __builtin_object_size(obj, 0)
#endif
#if GCC_VERSION >= 40300
/* Mark functions as cold. gcc will assume any path leading to a call
* to them will be unlikely. This means a lot of manual unlikely()s
* are unnecessary now for any paths leading to the usual suspects
* like BUG(), printk(), panic() etc. [but let's keep them for now for
* older compilers]
*
* Early snapshots of gcc 4.3 don't support this and we can't detect this
* in the preprocessor, but we can live with this because they're unreleased.
* Maketime probing would be overkill here.
*
* gcc also has a __attribute__((__hot__)) to move hot functions into
* a special section, but I don't see any sense in this right now in
* the kernel context
*/
#define __cold __attribute__((__cold__))
#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
#ifndef __CHECKER__
# define __compiletime_warning(message) __attribute__((warning(message)))
# define __compiletime_error(message) __attribute__((error(message)))
#endif /* __CHECKER__ */
#endif /* GCC_VERSION >= 40300 */
#if GCC_VERSION >= 40500
/*
* Mark a position in code as unreachable. This can be used to
* suppress control flow warnings after asm blocks that transfer
* control elsewhere.
*
* Early snapshots of gcc 4.5 don't support this and we can't detect
* this in the preprocessor, but we can live with this because they're
* unreleased. Really, we need to have autoconf for the kernel.
*/
#define unreachable() __builtin_unreachable()
/* Mark a function definition as prohibited from being cloned. */
#define __noclone __attribute__((__noclone__))
#endif /* GCC_VERSION >= 40500 */
#if GCC_VERSION >= 40600
/*
* Tell the optimizer that something else uses this function or variable.
*/
#define __visible __attribute__((externally_visible))
#endif
/*
* GCC 'asm goto' miscompiles certain code sequences:
*
* http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670
*
* Work it around via a compiler barrier quirk suggested by Jakub Jelinek.
*
* (asm goto is automatically volatile - the naming reflects this.)
*/
#define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0)
#ifdef CONFIG_ARCH_USE_BUILTIN_BSWAP
#if GCC_VERSION >= 40400
#define __HAVE_BUILTIN_BSWAP32__
#define __HAVE_BUILTIN_BSWAP64__
#endif
#if GCC_VERSION >= 40800 || (defined(__powerpc__) && GCC_VERSION >= 40600)
#define __HAVE_BUILTIN_BSWAP16__
#endif
#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */
#if GCC_VERSION >= 50000
#define KASAN_ABI_VERSION 4
#elif GCC_VERSION >= 40902
#define KASAN_ABI_VERSION 3
#endif
#endif /* gcc version >= 40000 specific checks */