Messages in this thread Patch in this message |  | | | Subject | [PATCH 3 of 8] x86: add _AT() macro to conditionally cast | | Date | Thu, 03 Jan 2008 12:11:00 -0800 | | From | Jeremy Fitzhardinge <> | |
# HG changeset patch
# User Jeremy Fitzhardinge <jeremy@xensource.com>
# Date 1199317452 28800
# Node ID f7e7db3facd9406545103164f9be8f9ba1a2b549
# Parent 4d9a413a0f4c1d98dbea704f0366457b5117045d
x86: add _AT() macro to conditionally cast
Define _AT(type, value) to conditionally cast a value when compiling C
code, but not when used in assembler.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
---
include/linux/const.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/include/linux/const.h b/include/linux/const.h
--- a/include/linux/const.h
+++ b/include/linux/const.h
@@ -7,13 +7,18 @@
* 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
#endif /* !(_LINUX_CONST_H) */
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