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- /* SPDX-License-Identifier: GPL-2.0 */
- #ifndef _LINUX_BUILD_BUG_H
- #define _LINUX_BUILD_BUG_H
- #include <linux/compiler.h>
- #ifdef __CHECKER__
- #define BUILD_BUG_ON_ZERO(e) (0)
- #else /* __CHECKER__ */
- /*
- * Force a compilation error if condition is true, but also produce a
- * result (of value 0 and type int), 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) ((int)(sizeof(struct { int:(-!!(e)); })))
- #endif /* __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) & ((n) - 1)) != 0)
- #define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
- BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
- /*
- * 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_MSG - break compile if a condition is true & emit supplied
- * error message.
- * @condition: the condition which the compiler should know is false.
- *
- * See BUILD_BUG_ON for description.
- */
- #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
- /**
- * 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
- * some other compile-time-evaluated condition, you should use BUILD_BUG_ON to
- * detect if someone changes it.
- */
- #define BUILD_BUG_ON(condition) \
- BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
- /**
- * 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() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed")
- /**
- * static_assert - check integer constant expression at build time
- *
- * static_assert() is a wrapper for the C11 _Static_assert, with a
- * little macro magic to make the message optional (defaulting to the
- * stringification of the tested expression).
- *
- * Contrary to BUILD_BUG_ON(), static_assert() can be used at global
- * scope, but requires the expression to be an integer constant
- * expression (i.e., it is not enough that __builtin_constant_p() is
- * true for expr).
- *
- * Also note that BUILD_BUG_ON() fails the build if the condition is
- * true, while static_assert() fails the build if the expression is
- * false.
- */
- #define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr)
- #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
- #endif /* _LINUX_BUILD_BUG_H */
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