Commit | Line | Data |
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94f582f8 RD |
1 | #ifndef __LINUX_COMPILER_H |
2 | #error "Please don't include <linux/compiler-gcc4.h> directly, include <linux/compiler.h> instead." | |
3 | #endif | |
1da177e4 | 4 | |
f9d14250 | 5 | /* GCC 4.1.[01] miscompiles __weak */ |
8cd2c29d PA |
6 | #ifdef __KERNEL__ |
7 | # if __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ <= 1 | |
8 | # error Your version of gcc miscompiles the __weak directive | |
9 | # endif | |
f9d14250 LT |
10 | #endif |
11 | ||
0d7ebbbc | 12 | #define __used __attribute__((__used__)) |
1da177e4 LT |
13 | #define __must_check __attribute__((warn_unused_result)) |
14 | #define __compiler_offsetof(a,b) __builtin_offsetof(a,b) | |
40fc55cb | 15 | #define __always_inline inline __attribute__((always_inline)) |
94909914 BP |
16 | |
17 | /* | |
18 | * A trick to suppress uninitialized variable warning without generating any | |
19 | * code | |
20 | */ | |
21 | #define uninitialized_var(x) x = x | |
a586df06 | 22 | |
f153b821 | 23 | #if __GNUC_MINOR__ >= 3 |
a586df06 AK |
24 | /* Mark functions as cold. gcc will assume any path leading to a call |
25 | to them will be unlikely. This means a lot of manual unlikely()s | |
26 | are unnecessary now for any paths leading to the usual suspects | |
27 | like BUG(), printk(), panic() etc. [but let's keep them for now for | |
28 | older compilers] | |
29 | ||
30 | Early snapshots of gcc 4.3 don't support this and we can't detect this | |
31 | in the preprocessor, but we can live with this because they're unreleased. | |
32 | Maketime probing would be overkill here. | |
33 | ||
34 | gcc also has a __attribute__((__hot__)) to move hot functions into | |
35 | a special section, but I don't see any sense in this right now in | |
36 | the kernel context */ | |
37 | #define __cold __attribute__((__cold__)) | |
38 | ||
38938c87 DD |
39 | |
40 | #if __GNUC_MINOR__ >= 5 | |
41 | /* | |
42 | * Mark a position in code as unreachable. This can be used to | |
43 | * suppress control flow warnings after asm blocks that transfer | |
44 | * control elsewhere. | |
45 | * | |
46 | * Early snapshots of gcc 4.5 don't support this and we can't detect | |
47 | * this in the preprocessor, but we can live with this because they're | |
48 | * unreleased. Really, we need to have autoconf for the kernel. | |
49 | */ | |
50 | #define unreachable() __builtin_unreachable() | |
9c695203 MP |
51 | |
52 | /* Mark a function definition as prohibited from being cloned. */ | |
53 | #define __noclone __attribute__((__noclone__)) | |
54 | ||
38938c87 DD |
55 | #endif |
56 | ||
a586df06 | 57 | #endif |
9f0cf4ad | 58 | |
7cff7ce9 | 59 | #if __GNUC_MINOR__ > 0 |
9f0cf4ad | 60 | #define __compiletime_object_size(obj) __builtin_object_size(obj, 0) |
7cff7ce9 | 61 | #endif |
4a312769 AV |
62 | #if __GNUC_MINOR__ >= 4 |
63 | #define __compiletime_warning(message) __attribute__((warning(message))) | |
63312b6a | 64 | #define __compiletime_error(message) __attribute__((error(message))) |
4a312769 | 65 | #endif |