1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_BUILD_BUG_H
3 #define _LINUX_BUILD_BUG_H
5 #include <linux/compiler.h>
8 #define __BUILD_BUG_ON_NOT_POWER_OF_2(n) (0)
9 #define BUILD_BUG_ON_NOT_POWER_OF_2(n) (0)
10 #define BUILD_BUG_ON_ZERO(e) (0)
11 #define BUILD_BUG_ON_INVALID(e) (0)
12 #define BUILD_BUG_ON_MSG(cond, msg) (0)
13 #define BUILD_BUG_ON(condition) (0)
14 #define BUILD_BUG() (0)
15 #else /* __CHECKER__ */
17 /* Force a compilation error if a constant expression is not a power of 2 */
18 #define __BUILD_BUG_ON_NOT_POWER_OF_2(n) \
19 BUILD_BUG_ON(((n) & ((n) - 1)) != 0)
20 #define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
21 BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
24 * Force a compilation error if condition is true, but also produce a
25 * result (of value 0 and type size_t), so the expression can be used
26 * e.g. in a structure initializer (or where-ever else comma expressions
29 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:(-!!(e)); }))
32 * BUILD_BUG_ON_INVALID() permits the compiler to check the validity of the
33 * expression but avoids the generation of any code, even if that expression
36 #define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e))))
39 * BUILD_BUG_ON_MSG - break compile if a condition is true & emit supplied
41 * @condition: the condition which the compiler should know is false.
43 * See BUILD_BUG_ON for description.
45 #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
48 * BUILD_BUG_ON - break compile if a condition is true.
49 * @condition: the condition which the compiler should know is false.
51 * If you have some code which relies on certain constants being equal, or
52 * some other compile-time-evaluated condition, you should use BUILD_BUG_ON to
53 * detect if someone changes it.
55 #define BUILD_BUG_ON(condition) \
56 BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
59 * BUILD_BUG - break compile if used.
61 * If you have some code that you expect the compiler to eliminate at
62 * build time, you should use BUILD_BUG to detect if it is
65 #define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed")
67 #endif /* __CHECKER__ */
69 #endif /* _LINUX_BUILD_BUG_H */