kernel-ark/include/linux/bug.h
Tushar Behera c5782e9f5a include/linux/bug.h: fix sparse warning related to BUILD_BUG_ON_INVALID
Commit baf05aa927 ("bug: introduce BUILD_BUG_ON_INVALID() macro")
introduces this macro only when _CHECKER_ is not defined.  Define a
silent macro in the else condition to fix following sparse warning:

  mm/filemap.c:395:9: error: undefined identifier 'BUILD_BUG_ON_INVALID'
  mm/filemap.c:396:9: error: undefined identifier 'BUILD_BUG_ON_INVALID'
  mm/filemap.c:397:9: error: undefined identifier 'BUILD_BUG_ON_INVALID'
  include/linux/mm.h:419:9: error: undefined identifier 'BUILD_BUG_ON_INVALID'
  include/linux/mm.h:419:9: error: not a function <noident>

Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Acked-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-26 17:41:24 -08:00

108 lines
3.2 KiB
C

#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 */