u-boot/include/linux/build_bug.h
Christophe Leroy 6ab7c3d6ba Fix sparse checks processing
A lot of errors are encountered when building with sparse checking
activated (make C=1 or make C=2).

Many of them are fixed in Linux.

Resynchronise Makefile and include/linux/build_bug.h with Linux
kernel sources by porting the following Linux commits into u-boot:
- 6c49f359ca14 ("kbuild: disable sparse warnings about unknown attributes")
- 80591e61a0f7 ("kbuild: tell sparse about the $ARCH")
- 8788994376d8 ("linux/build_bug.h: change type to int")
- 527edbc18a70 ("build_bug.h: remove most of dummy BUILD_BUG_ON stubs for Sparse")
- c60d3b79423a ("build_bug.h: remove negative-array fallback for BUILD_BUG_ON()")
- 14e83077d55f ("include: drop pointless __compiler_offsetof indirection")

Also revert commit aa9e891c63 ("include/linux/stddef.h: avoid
'warning: preprocessor token offsetof redefined'") because the
error it creates is worse than the warning it is trying to fix.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
2023-05-15 14:08:45 -04:00

79 lines
2.7 KiB
C

#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 */