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| author | Rusty Russell <rusty@rustcorp.com.au> | 2007-05-07 01:51:05 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-05-07 23:13:00 +0400 |
| commit | c5e631cf65f4d6875efcd571275436f2964a8b48 (patch) | |
| tree | 1aee9d61560ee369b4a2f077a79e37ab868a4b2d /include/linux/compiler-gcc.h | |
| parent | f34d9d2dcb7f17b64124841345b23adc0843e7a5 (diff) | |
| download | linux-c5e631cf65f4d6875efcd571275436f2964a8b48.tar.xz | |
ARRAY_SIZE: check for type
We can use a gcc extension to ensure that ARRAY_SIZE() is handed an array,
not a pointer. This is especially important when code is changed from a
fixed array to a pointer. I assume the Intel compiler doesn't support
__builtin_types_compatible_p.
[jdike@addtoit.com: uml: update UML definition of ARRAY_SIZE]
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/compiler-gcc.h')
| -rw-r--r-- | include/linux/compiler-gcc.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index 9008eabb9c3d..a9f794716a81 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -22,6 +22,9 @@ __asm__ ("" : "=r"(__ptr) : "0"(ptr)); \ (typeof(ptr)) (__ptr + (off)); }) +/* &a[0] degrades to a pointer: a different type from an array */ +#define __must_be_array(a) \ + BUILD_BUG_ON_ZERO(__builtin_types_compatible_p(typeof(a), typeof(&a[0]))) #define inline inline __attribute__((always_inline)) #define __inline__ __inline__ __attribute__((always_inline)) |