[deliverable/linux.git] / include / linux / bug.h

#ifndef _LINUX_BUG_H
#define _LINUX_BUG_H

#include <asm/bug.h>

enum bug_trap_type {
	BUG_TRAP_TYPE_NONE = 0,
	BUG_TRAP_TYPE_WARN = 1,
	BUG_TRAP_TYPE_BUG = 2,
};

struct pt_regs;

#ifdef __CHECKER__
#define BUILD_BUG_ON_NOT_POWER_OF_2(n)
#define BUILD_BUG_ON_ZERO(e) (0)
#define BUILD_BUG_ON_NULL(e) ((void*)0)
#define BUILD_BUG_ON_INVALID(e) (0)
#define BUILD_BUG_ON(condition)
#define BUILD_BUG() (0)
#else /* __CHECKER__ */

/* Force a compilation error if a constant expression is not a power of 2 */
#define BUILD_BUG_ON_NOT_POWER_OF_2(n)			\
	BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))

/* Force a compilation error if condition is true, but also produce a
   result (of value 0 and type size_t), so the expression can be used
   e.g. in a structure initializer (or where-ever else comma expressions
   aren't permitted). */
#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))

/*
 * BUILD_BUG_ON_INVALID() permits the compiler to check the validity of the
 * expression but avoids the generation of any code, even if that expression
 * has side-effects.
 */
#define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e))))

/**
 * BUILD_BUG_ON - break compile if a condition is true.
 * @condition: the condition which the compiler should know is false.
 *
 * If you have some code which relies on certain constants being equal, or
 * other compile-time-evaluated condition, you should use BUILD_BUG_ON to
 * detect if someone changes it.
 *
 * The implementation uses gcc's reluctance to create a negative array, but
 * gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments
 * to inline functions).  So as a fallback we use the optimizer; if it can't
 * prove the condition is false, it will cause a link error on the undefined
 * "__build_bug_on_failed".  This error message can be harder to track down
 * though, hence the two different methods.
 */
#ifndef __OPTIMIZE__
#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
#else
extern int __build_bug_on_failed;
#define BUILD_BUG_ON(condition)					\
	do {							\
		((void)sizeof(char[1 - 2*!!(condition)]));	\
		if (condition) __build_bug_on_failed = 1;	\
	} while(0)
#endif

/**
 * BUILD_BUG - break compile if used.
 *
 * If you have some code that you expect the compiler to eliminate at
 * build time, you should use BUILD_BUG to detect if it is
 * unexpectedly used.
 */
#define BUILD_BUG()						\
	do {							\
		extern void __build_bug_failed(void)		\
			__linktime_error("BUILD_BUG failed");	\
		__build_bug_failed();				\
	} while (0)

#endif	/* __CHECKER__ */

#ifdef CONFIG_GENERIC_BUG
#include <asm-generic/bug.h>

static inline int is_warning_bug(const struct bug_entry *bug)
{
	return bug->flags & BUGFLAG_WARNING;
}

const struct bug_entry *find_bug(unsigned long bugaddr);

enum bug_trap_type report_bug(unsigned long bug_addr, struct pt_regs *regs);

/* These are defined by the architecture */
int is_valid_bugaddr(unsigned long addr);

#else	/* !CONFIG_GENERIC_BUG */

static inline enum bug_trap_type report_bug(unsigned long bug_addr,
					    struct pt_regs *regs)
{
	return BUG_TRAP_TYPE_BUG;
}

#endif	/* CONFIG_GENERIC_BUG */
#endif	/* _LINUX_BUG_H */
Commit	Line	Data
7664c5a1 JF	1	#ifndef _LINUX_BUG_H
	2	#define _LINUX_BUG_H
	3
7664c5a1 JF	4	#include <asm/bug.h>
	5
	6	enum bug_trap_type {
	7	BUG_TRAP_TYPE_NONE = 0,
	8	BUG_TRAP_TYPE_WARN = 1,
	9	BUG_TRAP_TYPE_BUG = 2,
	10	};
	11
608e2619 HC	12	struct pt_regs;
608e2619 HC	13
35edd910 PG	14	#ifdef __CHECKER__
	15	#define BUILD_BUG_ON_NOT_POWER_OF_2(n)
	16	#define BUILD_BUG_ON_ZERO(e) (0)
	17	#define BUILD_BUG_ON_NULL(e) ((void*)0)
c5782e9f	18	#define BUILD_BUG_ON_INVALID(e) (0)
35edd910 PG	19	#define BUILD_BUG_ON(condition)
	20	#define BUILD_BUG() (0)
	21	#else /* __CHECKER__ */
	22
	23	/* Force a compilation error if a constant expression is not a power of 2 */
	24	#define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
	25	BUILD_BUG_ON((n) == 0 \|\| (((n) & ((n) - 1)) != 0))
	26
	27	/* Force a compilation error if condition is true, but also produce a
	28	result (of value 0 and type size_t), so the expression can be used
	29	e.g. in a structure initializer (or where-ever else comma expressions
	30	aren't permitted). */
	31	#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
	32	#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
	33
baf05aa9 KK	34	/*
	35	* BUILD_BUG_ON_INVALID() permits the compiler to check the validity of the
	36	* expression but avoids the generation of any code, even if that expression
	37	* has side-effects.
	38	*/
	39	#define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e))))
	40
35edd910 PG	41	/**
	42	* BUILD_BUG_ON - break compile if a condition is true.
	43	* @condition: the condition which the compiler should know is false.
	44	*
	45	* If you have some code which relies on certain constants being equal, or
	46	* other compile-time-evaluated condition, you should use BUILD_BUG_ON to
	47	* detect if someone changes it.
	48	*
	49	* The implementation uses gcc's reluctance to create a negative array, but
	50	* gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments
	51	* to inline functions). So as a fallback we use the optimizer; if it can't
	52	* prove the condition is false, it will cause a link error on the undefined
	53	* "__build_bug_on_failed". This error message can be harder to track down
	54	* though, hence the two different methods.
	55	*/
	56	#ifndef __OPTIMIZE__
	57	#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
	58	#else
	59	extern int __build_bug_on_failed;
	60	#define BUILD_BUG_ON(condition) \
	61	do { \
	62	((void)sizeof(char[1 - 2*!!(condition)])); \
	63	if (condition) __build_bug_on_failed = 1; \
	64	} while(0)
	65	#endif
	66
	67	/**
	68	* BUILD_BUG - break compile if used.
	69	*
	70	* If you have some code that you expect the compiler to eliminate at
	71	* build time, you should use BUILD_BUG to detect if it is
	72	* unexpectedly used.
	73	*/
	74	#define BUILD_BUG() \
	75	do { \
	76	extern void __build_bug_failed(void) \
	77	__linktime_error("BUILD_BUG failed"); \
	78	__build_bug_failed(); \
	79	} while (0)
	80
	81	#endif /* __CHECKER__ */
	82
7664c5a1 JF	83	#ifdef CONFIG_GENERIC_BUG
	84	#include <asm-generic/bug.h>
	85
	86	static inline int is_warning_bug(const struct bug_entry *bug)
	87	{
	88	return bug->flags & BUGFLAG_WARNING;
	89	}
	90
	91	const struct bug_entry *find_bug(unsigned long bugaddr);
	92
608e2619	93	enum bug_trap_type report_bug(unsigned long bug_addr, struct pt_regs *regs);
7664c5a1	94
7664c5a1 JF	95	/* These are defined by the architecture */
	96	int is_valid_bugaddr(unsigned long addr);
	97
	98	#else /* !CONFIG_GENERIC_BUG */
	99
608e2619 HC	100	static inline enum bug_trap_type report_bug(unsigned long bug_addr,
608e2619 HC	101	struct pt_regs *regs)
7664c5a1 JF	102	{
	103	return BUG_TRAP_TYPE_BUG;
	104	}
7664c5a1 JF	105
	106	#endif /* CONFIG_GENERIC_BUG */
	107	#endif /* _LINUX_BUG_H */