linux-stable-rt/include/linux/compiler-gcc.h

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/* Never include this file directly. Include <linux/compiler.h> instead. */
/*
* Common definitions for all gcc versions go here.
*/
/* Optimization barrier */
/* The "volatile" is due to gcc bugs */
#define barrier() __asm__ __volatile__("": : :"memory")
/* This macro obfuscates arithmetic on a variable address so that gcc
shouldn't recognize the original var, and make assumptions about it */
/*
* Versions of the ppc64 compiler before 4.1 had a bug where use of
* RELOC_HIDE could trash r30. The bug can be worked around by changing
* the inline assembly constraint from =g to =r, in this particular
* case either is valid.
*/
#define RELOC_HIDE(ptr, off) \
({ unsigned long __ptr; \
__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))
#define __inline __inline __attribute__((always_inline))
#define __deprecated __attribute__((deprecated))
[PATCH] extend the set of "__attribute__" shortcut macros Extend the set of "__attribute__" shortcut macros, and remove identical (and now superfluous) definitions from a couple of source files. based on a page at robert love's blog: http://rlove.org/log/2005102601 extend the set of shortcut macros defined in compiler-gcc.h with the following: #define __packed __attribute__((packed)) #define __weak __attribute__((weak)) #define __naked __attribute__((naked)) #define __noreturn __attribute__((noreturn)) #define __pure __attribute__((pure)) #define __aligned(x) __attribute__((aligned(x))) #define __printf(a,b) __attribute__((format(printf,a,b))) Once these are in place, it's up to subsystem maintainers to decide if they want to take advantage of them. there is already a strong precedent for using shortcuts like this in the source tree. The ones that might give people pause are "__aligned" and "__printf", but shortcuts for both of those are already in use, and in some ways very confusingly. note the two very different definitions for a macro named "ALIGNED": drivers/net/sgiseeq.c:#define ALIGNED(x) ((((unsigned long)(x)) + 0xf) & ~(0xf)) drivers/scsi/ultrastor.c:#define ALIGNED(x) __attribute__((aligned(x))) also: include/acpi/platform/acgcc.h: #define ACPI_PRINTF_LIKE(c) __attribute__ ((__format__ (__printf__, c, c+1))) Given the precedent, then, it seems logical to at least standardize on a consistent set of these macros. Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-10 17:46:20 +08:00
#define __packed __attribute__((packed))
#define __weak __attribute__((weak))
#define __naked __attribute__((naked))
#define __noreturn __attribute__((noreturn))
#define __pure __attribute__((pure))
#define __aligned(x) __attribute__((aligned(x)))
#define __printf(a,b) __attribute__((format(printf,a,b)))
#define noinline __attribute__((noinline))
#define __attribute_pure__ __attribute__((pure))
#define __attribute_const__ __attribute__((__const__))
#define __maybe_unused __attribute__((unused))