Re: [PATCH 1/2] Add C99-style constructor macros for specific-sizedintegers

From: H. Peter Anvin
Date: Mon Mar 03 2008 - 12:05:18 EST


Sam Ravnborg wrote:

And in linux/const.h we have yet another variant:
/* Some constant macros are used in both assembler and
* C code. Therefore we cannot annotate them always with
* 'UL' and other type specifiers unilaterally. We
* use the following macros to deal with this.
*
* Similarly, _AT() will cast an expression with a type in C, but
* leave it unchanged in asm.
*/

#ifdef __ASSEMBLY__
#define _AC(X,Y) X
#define _AT(T,X) X
#else
#define __AC(X,Y) (X##Y)
#define _AC(X,Y) __AC(X,Y)
#define _AT(T,X) ((T)(X))
#endif

Not as typestrict as hpa's and arm's version but
used in a few placed already.


These, unfortunately, don't solve the issue of gcc warnings, and you don't want to make them paste ULL on before the cast, since I think they're used with non-simple constants.

-hpa
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