35edd9103c
The support for BUILD_BUG in linux/kernel.h predates the
addition of linux/bug.h -- with this chunk off separate,
you can run into situations where a person gets a compile
fail even when they've included linux/bug.h, like this:
CC lib/string.o
lib/string.c: In function 'strlcat':
lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
make[2]: *** [lib/string.o] Error 1
$
$ grep linux/bug.h lib/string.c
#include <linux/bug.h>
$
Since the above violates the principle of least surprise, move
the BUG chunks from kernel.h to bug.h so it is all together.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
99 lines
2.9 KiB
C
99 lines
2.9 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(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 - 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 */
|