bug.h

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#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))))

#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

#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 */