| #ifndef __LINUX_COMPILER_H |
| #error "Please don't include <linux/compiler-gcc4.h> directly, include <linux/compiler.h> instead." |
| #endif |
| |
| /* GCC 4.1.[01] miscompiles __weak */ |
| #ifdef __KERNEL__ |
| # if __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ <= 1 |
| # error Your version of gcc miscompiles the __weak directive |
| # endif |
| #endif |
| |
| #define __used __attribute__((__used__)) |
| #define __must_check __attribute__((warn_unused_result)) |
| #define __compiler_offsetof(a,b) __builtin_offsetof(a,b) |
| |
| #if __GNUC_MINOR__ >= 3 |
| /* Mark functions as cold. gcc will assume any path leading to a call |
| to them will be unlikely. This means a lot of manual unlikely()s |
| are unnecessary now for any paths leading to the usual suspects |
| like BUG(), printk(), panic() etc. [but let's keep them for now for |
| older compilers] |
| |
| Early snapshots of gcc 4.3 don't support this and we can't detect this |
| in the preprocessor, but we can live with this because they're unreleased. |
| Maketime probing would be overkill here. |
| |
| gcc also has a __attribute__((__hot__)) to move hot functions into |
| a special section, but I don't see any sense in this right now in |
| the kernel context */ |
| #define __cold __attribute__((__cold__)) |
| |
| #define __linktime_error(message) __attribute__((__error__(message))) |
| |
| /* |
| * GCC 'asm goto' miscompiles certain code sequences: |
| * |
| * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670 |
| * |
| * Work it around via a compiler barrier quirk suggested by Jakub Jelinek. |
| * Fixed in GCC 4.8.2 and later versions. |
| * |
| * (asm goto is automatically volatile - the naming reflects this.) |
| */ |
| #if GCC_VERSION <= 40801 |
| # define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0) |
| #else |
| # define asm_volatile_goto(x...) do { asm goto(x); } while (0) |
| #endif |
| |
| #if __GNUC_MINOR__ >= 5 |
| /* |
| * Mark a position in code as unreachable. This can be used to |
| * suppress control flow warnings after asm blocks that transfer |
| * control elsewhere. |
| * |
| * Early snapshots of gcc 4.5 don't support this and we can't detect |
| * this in the preprocessor, but we can live with this because they're |
| * unreleased. Really, we need to have autoconf for the kernel. |
| */ |
| #define unreachable() __builtin_unreachable() |
| |
| /* Mark a function definition as prohibited from being cloned. */ |
| #define __noclone __attribute__((__noclone__)) |
| |
| #endif |
| #endif |
| |
| #if __GNUC_MINOR__ > 0 |
| #define __compiletime_object_size(obj) __builtin_object_size(obj, 0) |
| #endif |
| #if __GNUC_MINOR__ >= 4 && !defined(__CHECKER__) |
| #define __compiletime_warning(message) __attribute__((warning(message))) |
| #define __compiletime_error(message) __attribute__((error(message))) |
| #endif |