xref: /linux/include/uapi/linux/const.h (revision 6ed7ffddcf61f668114edb676417e5fb33773b59)
1 /* const.h: Macros for dealing with constants.  */
2 
3 #ifndef _LINUX_CONST_H
4 #define _LINUX_CONST_H
5 
6 /* Some constant macros are used in both assembler and
7  * C code.  Therefore we cannot annotate them always with
8  * 'UL' and other type specifiers unilaterally.  We
9  * use the following macros to deal with this.
10  *
11  * Similarly, _AT() will cast an expression with a type in C, but
12  * leave it unchanged in asm.
13  */
14 
15 #ifdef __ASSEMBLY__
16 #define _AC(X,Y)	X
17 #define _AT(T,X)	X
18 #else
19 #define __AC(X,Y)	(X##Y)
20 #define _AC(X,Y)	__AC(X,Y)
21 #define _AT(T,X)	((T)(X))
22 #endif
23 
24 #endif /* !(_LINUX_CONST_H) */
25