diff options
author | Nick Desaulniers <ndesaulniers@google.com> | 2018-08-22 19:37:24 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-22 20:31:34 -0400 |
commit | 815f0ddb346c196018d4d8f8f55c12b83da1de3f (patch) | |
tree | 4805bf7e3cb7ec4e727aba8e62f9211e9001a760 | |
parent | 899fbc33fd775b9dfa363db28f322272920a2196 (diff) |
include/linux/compiler*.h: make compiler-*.h mutually exclusive
Commit cafa0010cd51 ("Raise the minimum required gcc version to 4.6")
recently exposed a brittle part of the build for supporting non-gcc
compilers.
Both Clang and ICC define __GNUC__, __GNUC_MINOR__, and
__GNUC_PATCHLEVEL__ for quick compatibility with code bases that haven't
added compiler specific checks for __clang__ or __INTEL_COMPILER.
This is brittle, as they happened to get compatibility by posing as a
certain version of GCC. This broke when upgrading the minimal version
of GCC required to build the kernel, to a version above what ICC and
Clang claim to be.
Rather than always including compiler-gcc.h then undefining or
redefining macros in compiler-intel.h or compiler-clang.h, let's
separate out the compiler specific macro definitions into mutually
exclusive headers, do more proper compiler detection, and keep shared
definitions in compiler_types.h.
Fixes: cafa0010cd51 ("Raise the minimum required gcc version to 4.6")
Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Suggested-by: Eli Friedman <efriedma@codeaurora.org>
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | arch/arm/kernel/asm-offsets.c | 13 | ||||
-rw-r--r-- | drivers/gpu/drm/i915/i915_utils.h | 2 | ||||
-rw-r--r-- | drivers/watchdog/kempld_wdt.c | 5 | ||||
-rw-r--r-- | include/linux/compiler-clang.h | 20 | ||||
-rw-r--r-- | include/linux/compiler-gcc.h | 88 | ||||
-rw-r--r-- | include/linux/compiler-intel.h | 13 | ||||
-rw-r--r-- | include/linux/compiler_types.h | 238 | ||||
-rw-r--r-- | mm/ksm.c | 4 | ||||
-rw-r--r-- | mm/migrate.c | 3 |
9 files changed, 133 insertions, 253 deletions
diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c index 974d8d7d1bcd..3968d6c22455 100644 --- a/arch/arm/kernel/asm-offsets.c +++ b/arch/arm/kernel/asm-offsets.c | |||
@@ -38,25 +38,14 @@ | |||
38 | #error Sorry, your compiler targets APCS-26 but this kernel requires APCS-32 | 38 | #error Sorry, your compiler targets APCS-26 but this kernel requires APCS-32 |
39 | #endif | 39 | #endif |
40 | /* | 40 | /* |
41 | * GCC 3.0, 3.1: general bad code generation. | ||
42 | * GCC 3.2.0: incorrect function argument offset calculation. | ||
43 | * GCC 3.2.x: miscompiles NEW_AUX_ENT in fs/binfmt_elf.c | ||
44 | * (http://gcc.gnu.org/PR8896) and incorrect structure | ||
45 | * initialisation in fs/jffs2/erase.c | ||
46 | * GCC 4.8.0-4.8.2: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58854 | 41 | * GCC 4.8.0-4.8.2: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58854 |
47 | * miscompiles find_get_entry(), and can result in EXT3 and EXT4 | 42 | * miscompiles find_get_entry(), and can result in EXT3 and EXT4 |
48 | * filesystem corruption (possibly other FS too). | 43 | * filesystem corruption (possibly other FS too). |
49 | */ | 44 | */ |
50 | #ifdef __GNUC__ | 45 | #if defined(GCC_VERSION) && GCC_VERSION >= 40800 && GCC_VERSION < 40803 |
51 | #if (__GNUC__ == 3 && __GNUC_MINOR__ < 3) | ||
52 | #error Your compiler is too buggy; it is known to miscompile kernels. | ||
53 | #error Known good compilers: 3.3, 4.x | ||
54 | #endif | ||
55 | #if GCC_VERSION >= 40800 && GCC_VERSION < 40803 | ||
56 | #error Your compiler is too buggy; it is known to miscompile kernels | 46 | #error Your compiler is too buggy; it is known to miscompile kernels |
57 | #error and result in filesystem corruption and oopses. | 47 | #error and result in filesystem corruption and oopses. |
58 | #endif | 48 | #endif |
59 | #endif | ||
60 | 49 | ||
61 | int main(void) | 50 | int main(void) |
62 | { | 51 | { |
diff --git a/drivers/gpu/drm/i915/i915_utils.h b/drivers/gpu/drm/i915/i915_utils.h index 00165ad55fb3..395dd2511568 100644 --- a/drivers/gpu/drm/i915/i915_utils.h +++ b/drivers/gpu/drm/i915/i915_utils.h | |||
@@ -43,7 +43,7 @@ | |||
43 | #define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \ | 43 | #define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \ |
44 | __stringify(x), (long)(x)) | 44 | __stringify(x), (long)(x)) |
45 | 45 | ||
46 | #if GCC_VERSION >= 70000 | 46 | #if defined(GCC_VERSION) && GCC_VERSION >= 70000 |
47 | #define add_overflows(A, B) \ | 47 | #define add_overflows(A, B) \ |
48 | __builtin_add_overflow_p((A), (B), (typeof((A) + (B)))0) | 48 | __builtin_add_overflow_p((A), (B), (typeof((A) + (B)))0) |
49 | #else | 49 | #else |
diff --git a/drivers/watchdog/kempld_wdt.c b/drivers/watchdog/kempld_wdt.c index 2f3b049ea301..e268add43010 100644 --- a/drivers/watchdog/kempld_wdt.c +++ b/drivers/watchdog/kempld_wdt.c | |||
@@ -146,12 +146,7 @@ static int kempld_wdt_set_stage_timeout(struct kempld_wdt_data *wdt_data, | |||
146 | u32 remainder; | 146 | u32 remainder; |
147 | u8 stage_cfg; | 147 | u8 stage_cfg; |
148 | 148 | ||
149 | #if GCC_VERSION < 40400 | ||
150 | /* work around a bug compiling do_div() */ | ||
151 | prescaler = READ_ONCE(kempld_prescaler[PRESCALER_21]); | ||
152 | #else | ||
153 | prescaler = kempld_prescaler[PRESCALER_21]; | 149 | prescaler = kempld_prescaler[PRESCALER_21]; |
154 | #endif | ||
155 | 150 | ||
156 | if (!stage) | 151 | if (!stage) |
157 | return -EINVAL; | 152 | return -EINVAL; |
diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h index 7087446c24c8..b1ce500fe8b3 100644 --- a/include/linux/compiler-clang.h +++ b/include/linux/compiler-clang.h | |||
@@ -6,11 +6,7 @@ | |||
6 | /* Some compiler specific definitions are overwritten here | 6 | /* Some compiler specific definitions are overwritten here |
7 | * for Clang compiler | 7 | * for Clang compiler |
8 | */ | 8 | */ |
9 | |||
10 | #ifdef uninitialized_var | ||
11 | #undef uninitialized_var | ||
12 | #define uninitialized_var(x) x = *(&(x)) | 9 | #define uninitialized_var(x) x = *(&(x)) |
13 | #endif | ||
14 | 10 | ||
15 | /* same as gcc, this was present in clang-2.6 so we can assume it works | 11 | /* same as gcc, this was present in clang-2.6 so we can assume it works |
16 | * with any version that can compile the kernel | 12 | * with any version that can compile the kernel |
@@ -25,14 +21,8 @@ | |||
25 | #define __SANITIZE_ADDRESS__ | 21 | #define __SANITIZE_ADDRESS__ |
26 | #endif | 22 | #endif |
27 | 23 | ||
28 | #undef __no_sanitize_address | ||
29 | #define __no_sanitize_address __attribute__((no_sanitize("address"))) | 24 | #define __no_sanitize_address __attribute__((no_sanitize("address"))) |
30 | 25 | ||
31 | /* Clang doesn't have a way to turn it off per-function, yet. */ | ||
32 | #ifdef __noretpoline | ||
33 | #undef __noretpoline | ||
34 | #endif | ||
35 | |||
36 | /* | 26 | /* |
37 | * Not all versions of clang implement the the type-generic versions | 27 | * Not all versions of clang implement the the type-generic versions |
38 | * of the builtin overflow checkers. Fortunately, clang implements | 28 | * of the builtin overflow checkers. Fortunately, clang implements |
@@ -40,9 +30,17 @@ | |||
40 | * checks. Unfortunately, we don't know which version of gcc clang | 30 | * checks. Unfortunately, we don't know which version of gcc clang |
41 | * pretends to be, so the macro may or may not be defined. | 31 | * pretends to be, so the macro may or may not be defined. |
42 | */ | 32 | */ |
43 | #undef COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW | ||
44 | #if __has_builtin(__builtin_mul_overflow) && \ | 33 | #if __has_builtin(__builtin_mul_overflow) && \ |
45 | __has_builtin(__builtin_add_overflow) && \ | 34 | __has_builtin(__builtin_add_overflow) && \ |
46 | __has_builtin(__builtin_sub_overflow) | 35 | __has_builtin(__builtin_sub_overflow) |
47 | #define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1 | 36 | #define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1 |
48 | #endif | 37 | #endif |
38 | |||
39 | /* The following are for compatibility with GCC, from compiler-gcc.h, | ||
40 | * and may be redefined here because they should not be shared with other | ||
41 | * compilers, like ICC. | ||
42 | */ | ||
43 | #define barrier() __asm__ __volatile__("" : : : "memory") | ||
44 | #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) | ||
45 | #define __assume_aligned(a, ...) \ | ||
46 | __attribute__((__assume_aligned__(a, ## __VA_ARGS__))) | ||
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index 250b9b7cfd60..763bbad1e258 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h | |||
@@ -75,48 +75,6 @@ | |||
75 | #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) | 75 | #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) |
76 | #endif | 76 | #endif |
77 | 77 | ||
78 | /* | ||
79 | * Feature detection for gnu_inline (gnu89 extern inline semantics). Either | ||
80 | * __GNUC_STDC_INLINE__ is defined (not using gnu89 extern inline semantics, | ||
81 | * and we opt in to the gnu89 semantics), or __GNUC_STDC_INLINE__ is not | ||
82 | * defined so the gnu89 semantics are the default. | ||
83 | */ | ||
84 | #ifdef __GNUC_STDC_INLINE__ | ||
85 | # define __gnu_inline __attribute__((gnu_inline)) | ||
86 | #else | ||
87 | # define __gnu_inline | ||
88 | #endif | ||
89 | |||
90 | /* | ||
91 | * Force always-inline if the user requests it so via the .config, | ||
92 | * or if gcc is too old. | ||
93 | * GCC does not warn about unused static inline functions for | ||
94 | * -Wunused-function. This turns out to avoid the need for complex #ifdef | ||
95 | * directives. Suppress the warning in clang as well by using "unused" | ||
96 | * function attribute, which is redundant but not harmful for gcc. | ||
97 | * Prefer gnu_inline, so that extern inline functions do not emit an | ||
98 | * externally visible function. This makes extern inline behave as per gnu89 | ||
99 | * semantics rather than c99. This prevents multiple symbol definition errors | ||
100 | * of extern inline functions at link time. | ||
101 | * A lot of inline functions can cause havoc with function tracing. | ||
102 | */ | ||
103 | #if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ | ||
104 | !defined(CONFIG_OPTIMIZE_INLINING) | ||
105 | #define inline \ | ||
106 | inline __attribute__((always_inline, unused)) notrace __gnu_inline | ||
107 | #else | ||
108 | #define inline inline __attribute__((unused)) notrace __gnu_inline | ||
109 | #endif | ||
110 | |||
111 | #define __inline__ inline | ||
112 | #define __inline inline | ||
113 | #define __always_inline inline __attribute__((always_inline)) | ||
114 | #define noinline __attribute__((noinline)) | ||
115 | |||
116 | #define __packed __attribute__((packed)) | ||
117 | #define __weak __attribute__((weak)) | ||
118 | #define __alias(symbol) __attribute__((alias(#symbol))) | ||
119 | |||
120 | #ifdef RETPOLINE | 78 | #ifdef RETPOLINE |
121 | #define __noretpoline __attribute__((indirect_branch("keep"))) | 79 | #define __noretpoline __attribute__((indirect_branch("keep"))) |
122 | #endif | 80 | #endif |
@@ -135,55 +93,9 @@ | |||
135 | */ | 93 | */ |
136 | #define __naked __attribute__((naked)) noinline __noclone notrace | 94 | #define __naked __attribute__((naked)) noinline __noclone notrace |
137 | 95 | ||
138 | #define __noreturn __attribute__((noreturn)) | ||
139 | |||
140 | /* | ||
141 | * From the GCC manual: | ||
142 | * | ||
143 | * Many functions have no effects except the return value and their | ||
144 | * return value depends only on the parameters and/or global | ||
145 | * variables. Such a function can be subject to common subexpression | ||
146 | * elimination and loop optimization just as an arithmetic operator | ||
147 | * would be. | ||
148 | * [...] | ||
149 | */ | ||
150 | #define __pure __attribute__((pure)) | ||
151 | #define __aligned(x) __attribute__((aligned(x))) | ||
152 | #define __aligned_largest __attribute__((aligned)) | ||
153 | #define __printf(a, b) __attribute__((format(printf, a, b))) | ||
154 | #define __scanf(a, b) __attribute__((format(scanf, a, b))) | ||
155 | #define __attribute_const__ __attribute__((__const__)) | ||
156 | #define __maybe_unused __attribute__((unused)) | ||
157 | #define __always_unused __attribute__((unused)) | ||
158 | #define __mode(x) __attribute__((mode(x))) | ||
159 | |||
160 | #define __must_check __attribute__((warn_unused_result)) | ||
161 | #define __malloc __attribute__((__malloc__)) | ||
162 | |||
163 | #define __used __attribute__((__used__)) | ||
164 | #define __compiler_offsetof(a, b) \ | ||
165 | __builtin_offsetof(a, b) | ||
166 | |||
167 | /* Mark functions as cold. gcc will assume any path leading to a call | ||
168 | * to them will be unlikely. This means a lot of manual unlikely()s | ||
169 | * are unnecessary now for any paths leading to the usual suspects | ||
170 | * like BUG(), printk(), panic() etc. [but let's keep them for now for | ||
171 | * older compilers] | ||
172 | * | ||
173 | * Early snapshots of gcc 4.3 don't support this and we can't detect this | ||
174 | * in the preprocessor, but we can live with this because they're unreleased. | ||
175 | * Maketime probing would be overkill here. | ||
176 | * | ||
177 | * gcc also has a __attribute__((__hot__)) to move hot functions into | ||
178 | * a special section, but I don't see any sense in this right now in | ||
179 | * the kernel context | ||
180 | */ | ||
181 | #define __cold __attribute__((__cold__)) | ||
182 | |||
183 | #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) | 96 | #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) |
184 | 97 | ||
185 | #define __optimize(level) __attribute__((__optimize__(level))) | 98 | #define __optimize(level) __attribute__((__optimize__(level))) |
186 | #define __nostackprotector __optimize("no-stack-protector") | ||
187 | 99 | ||
188 | #define __compiletime_object_size(obj) __builtin_object_size(obj, 0) | 100 | #define __compiletime_object_size(obj) __builtin_object_size(obj, 0) |
189 | 101 | ||
diff --git a/include/linux/compiler-intel.h b/include/linux/compiler-intel.h index 547cdc920a3c..4c7f9befa9f6 100644 --- a/include/linux/compiler-intel.h +++ b/include/linux/compiler-intel.h | |||
@@ -14,10 +14,6 @@ | |||
14 | /* Intel ECC compiler doesn't support gcc specific asm stmts. | 14 | /* Intel ECC compiler doesn't support gcc specific asm stmts. |
15 | * It uses intrinsics to do the equivalent things. | 15 | * It uses intrinsics to do the equivalent things. |
16 | */ | 16 | */ |
17 | #undef barrier | ||
18 | #undef barrier_data | ||
19 | #undef RELOC_HIDE | ||
20 | #undef OPTIMIZER_HIDE_VAR | ||
21 | 17 | ||
22 | #define barrier() __memory_barrier() | 18 | #define barrier() __memory_barrier() |
23 | #define barrier_data(ptr) barrier() | 19 | #define barrier_data(ptr) barrier() |
@@ -38,13 +34,12 @@ | |||
38 | 34 | ||
39 | #endif | 35 | #endif |
40 | 36 | ||
41 | #ifndef __HAVE_BUILTIN_BSWAP16__ | ||
42 | /* icc has this, but it's called _bswap16 */ | 37 | /* icc has this, but it's called _bswap16 */ |
43 | #define __HAVE_BUILTIN_BSWAP16__ | 38 | #define __HAVE_BUILTIN_BSWAP16__ |
44 | #define __builtin_bswap16 _bswap16 | 39 | #define __builtin_bswap16 _bswap16 |
45 | #endif | ||
46 | 40 | ||
47 | /* | 41 | /* The following are for compatibility with GCC, from compiler-gcc.h, |
48 | * icc defines __GNUC__, but does not implement the builtin overflow checkers. | 42 | * and may be redefined here because they should not be shared with other |
43 | * compilers, like clang. | ||
49 | */ | 44 | */ |
50 | #undef COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW | 45 | #define __visible __attribute__((externally_visible)) |
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h index fbf337933fd8..90479a0f3986 100644 --- a/include/linux/compiler_types.h +++ b/include/linux/compiler_types.h | |||
@@ -54,32 +54,20 @@ extern void __chk_io_ptr(const volatile void __iomem *); | |||
54 | 54 | ||
55 | #ifdef __KERNEL__ | 55 | #ifdef __KERNEL__ |
56 | 56 | ||
57 | #ifdef __GNUC__ | 57 | /* Compiler specific macros. */ |
58 | #include <linux/compiler-gcc.h> | ||
59 | #endif | ||
60 | |||
61 | #if defined(CC_USING_HOTPATCH) && !defined(__CHECKER__) | ||
62 | #define notrace __attribute__((hotpatch(0,0))) | ||
63 | #else | ||
64 | #define notrace __attribute__((no_instrument_function)) | ||
65 | #endif | ||
66 | |||
67 | /* Intel compiler defines __GNUC__. So we will overwrite implementations | ||
68 | * coming from above header files here | ||
69 | */ | ||
70 | #ifdef __INTEL_COMPILER | ||
71 | # include <linux/compiler-intel.h> | ||
72 | #endif | ||
73 | |||
74 | /* Clang compiler defines __GNUC__. So we will overwrite implementations | ||
75 | * coming from above header files here | ||
76 | */ | ||
77 | #ifdef __clang__ | 58 | #ifdef __clang__ |
78 | #include <linux/compiler-clang.h> | 59 | #include <linux/compiler-clang.h> |
60 | #elif defined(__INTEL_COMPILER) | ||
61 | #include <linux/compiler-intel.h> | ||
62 | #elif defined(__GNUC__) | ||
63 | /* The above compilers also define __GNUC__, so order is important here. */ | ||
64 | #include <linux/compiler-gcc.h> | ||
65 | #else | ||
66 | #error "Unknown compiler" | ||
79 | #endif | 67 | #endif |
80 | 68 | ||
81 | /* | 69 | /* |
82 | * Generic compiler-dependent macros required for kernel | 70 | * Generic compiler-independent macros required for kernel |
83 | * build go below this comment. Actual compiler/compiler version | 71 | * build go below this comment. Actual compiler/compiler version |
84 | * specific implementations come from the above header files | 72 | * specific implementations come from the above header files |
85 | */ | 73 | */ |
@@ -106,93 +94,19 @@ struct ftrace_likely_data { | |||
106 | unsigned long constant; | 94 | unsigned long constant; |
107 | }; | 95 | }; |
108 | 96 | ||
109 | #endif /* __KERNEL__ */ | ||
110 | |||
111 | #endif /* __ASSEMBLY__ */ | ||
112 | |||
113 | #ifdef __KERNEL__ | ||
114 | |||
115 | /* Don't. Just don't. */ | 97 | /* Don't. Just don't. */ |
116 | #define __deprecated | 98 | #define __deprecated |
117 | #define __deprecated_for_modules | 99 | #define __deprecated_for_modules |
118 | 100 | ||
119 | #ifndef __must_check | ||
120 | #define __must_check | ||
121 | #endif | ||
122 | |||
123 | #ifndef CONFIG_ENABLE_MUST_CHECK | ||
124 | #undef __must_check | ||
125 | #define __must_check | ||
126 | #endif | ||
127 | |||
128 | #ifndef __malloc | ||
129 | #define __malloc | ||
130 | #endif | ||
131 | |||
132 | /* | ||
133 | * Allow us to avoid 'defined but not used' warnings on functions and data, | ||
134 | * as well as force them to be emitted to the assembly file. | ||
135 | * | ||
136 | * As of gcc 3.4, static functions that are not marked with attribute((used)) | ||
137 | * may be elided from the assembly file. As of gcc 3.4, static data not so | ||
138 | * marked will not be elided, but this may change in a future gcc version. | ||
139 | * | ||
140 | * NOTE: Because distributions shipped with a backported unit-at-a-time | ||
141 | * compiler in gcc 3.3, we must define __used to be __attribute__((used)) | ||
142 | * for gcc >=3.3 instead of 3.4. | ||
143 | * | ||
144 | * In prior versions of gcc, such functions and data would be emitted, but | ||
145 | * would be warned about except with attribute((unused)). | ||
146 | * | ||
147 | * Mark functions that are referenced only in inline assembly as __used so | ||
148 | * the code is emitted even though it appears to be unreferenced. | ||
149 | */ | ||
150 | #ifndef __used | ||
151 | # define __used /* unimplemented */ | ||
152 | #endif | ||
153 | |||
154 | #ifndef __maybe_unused | ||
155 | # define __maybe_unused /* unimplemented */ | ||
156 | #endif | ||
157 | |||
158 | #ifndef __always_unused | ||
159 | # define __always_unused /* unimplemented */ | ||
160 | #endif | ||
161 | |||
162 | #ifndef noinline | ||
163 | #define noinline | ||
164 | #endif | ||
165 | |||
166 | /* | ||
167 | * Rather then using noinline to prevent stack consumption, use | ||
168 | * noinline_for_stack instead. For documentation reasons. | ||
169 | */ | ||
170 | #define noinline_for_stack noinline | ||
171 | |||
172 | #ifndef __always_inline | ||
173 | #define __always_inline inline | ||
174 | #endif | ||
175 | |||
176 | #endif /* __KERNEL__ */ | 101 | #endif /* __KERNEL__ */ |
177 | 102 | ||
103 | #endif /* __ASSEMBLY__ */ | ||
104 | |||
178 | /* | 105 | /* |
179 | * From the GCC manual: | 106 | * The below symbols may be defined for one or more, but not ALL, of the above |
180 | * | 107 | * compilers. We don't consider that to be an error, so set them to nothing. |
181 | * Many functions do not examine any values except their arguments, | 108 | * For example, some of them are for compiler specific plugins. |
182 | * and have no effects except the return value. Basically this is | ||
183 | * just slightly more strict class than the `pure' attribute above, | ||
184 | * since function is not allowed to read global memory. | ||
185 | * | ||
186 | * Note that a function that has pointer arguments and examines the | ||
187 | * data pointed to must _not_ be declared `const'. Likewise, a | ||
188 | * function that calls a non-`const' function usually must not be | ||
189 | * `const'. It does not make sense for a `const' function to return | ||
190 | * `void'. | ||
191 | */ | 109 | */ |
192 | #ifndef __attribute_const__ | ||
193 | # define __attribute_const__ /* unimplemented */ | ||
194 | #endif | ||
195 | |||
196 | #ifndef __designated_init | 110 | #ifndef __designated_init |
197 | # define __designated_init | 111 | # define __designated_init |
198 | #endif | 112 | #endif |
@@ -214,28 +128,10 @@ struct ftrace_likely_data { | |||
214 | # define randomized_struct_fields_end | 128 | # define randomized_struct_fields_end |
215 | #endif | 129 | #endif |
216 | 130 | ||
217 | /* | ||
218 | * Tell gcc if a function is cold. The compiler will assume any path | ||
219 | * directly leading to the call is unlikely. | ||
220 | */ | ||
221 | |||
222 | #ifndef __cold | ||
223 | #define __cold | ||
224 | #endif | ||
225 | |||
226 | /* Simple shorthand for a section definition */ | ||
227 | #ifndef __section | ||
228 | # define __section(S) __attribute__ ((__section__(#S))) | ||
229 | #endif | ||
230 | |||
231 | #ifndef __visible | 131 | #ifndef __visible |
232 | #define __visible | 132 | #define __visible |
233 | #endif | 133 | #endif |
234 | 134 | ||
235 | #ifndef __nostackprotector | ||
236 | # define __nostackprotector | ||
237 | #endif | ||
238 | |||
239 | /* | 135 | /* |
240 | * Assume alignment of return value. | 136 | * Assume alignment of return value. |
241 | */ | 137 | */ |
@@ -243,17 +139,23 @@ struct ftrace_likely_data { | |||
243 | #define __assume_aligned(a, ...) | 139 | #define __assume_aligned(a, ...) |
244 | #endif | 140 | #endif |
245 | 141 | ||
246 | |||
247 | /* Are two types/vars the same type (ignoring qualifiers)? */ | 142 | /* Are two types/vars the same type (ignoring qualifiers)? */ |
248 | #ifndef __same_type | 143 | #define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) |
249 | # define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) | ||
250 | #endif | ||
251 | 144 | ||
252 | /* Is this type a native word size -- useful for atomic operations */ | 145 | /* Is this type a native word size -- useful for atomic operations */ |
253 | #ifndef __native_word | 146 | #define __native_word(t) \ |
254 | # define __native_word(t) (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long)) | 147 | (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \ |
148 | sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long)) | ||
149 | |||
150 | #ifndef __attribute_const__ | ||
151 | #define __attribute_const__ __attribute__((__const__)) | ||
255 | #endif | 152 | #endif |
256 | 153 | ||
154 | #ifndef __noclone | ||
155 | #define __noclone | ||
156 | #endif | ||
157 | |||
158 | /* Helpers for emitting diagnostics in pragmas. */ | ||
257 | #ifndef __diag | 159 | #ifndef __diag |
258 | #define __diag(string) | 160 | #define __diag(string) |
259 | #endif | 161 | #endif |
@@ -272,4 +174,92 @@ struct ftrace_likely_data { | |||
272 | #define __diag_error(compiler, version, option, comment) \ | 174 | #define __diag_error(compiler, version, option, comment) \ |
273 | __diag_ ## compiler(version, error, option) | 175 | __diag_ ## compiler(version, error, option) |
274 | 176 | ||
177 | /* | ||
178 | * From the GCC manual: | ||
179 | * | ||
180 | * Many functions have no effects except the return value and their | ||
181 | * return value depends only on the parameters and/or global | ||
182 | * variables. Such a function can be subject to common subexpression | ||
183 | * elimination and loop optimization just as an arithmetic operator | ||
184 | * would be. | ||
185 | * [...] | ||
186 | */ | ||
187 | #define __pure __attribute__((pure)) | ||
188 | #define __aligned(x) __attribute__((aligned(x))) | ||
189 | #define __aligned_largest __attribute__((aligned)) | ||
190 | #define __printf(a, b) __attribute__((format(printf, a, b))) | ||
191 | #define __scanf(a, b) __attribute__((format(scanf, a, b))) | ||
192 | #define __maybe_unused __attribute__((unused)) | ||
193 | #define __always_unused __attribute__((unused)) | ||
194 | #define __mode(x) __attribute__((mode(x))) | ||
195 | #define __malloc __attribute__((__malloc__)) | ||
196 | #define __used __attribute__((__used__)) | ||
197 | #define __noreturn __attribute__((noreturn)) | ||
198 | #define __packed __attribute__((packed)) | ||
199 | #define __weak __attribute__((weak)) | ||
200 | #define __alias(symbol) __attribute__((alias(#symbol))) | ||
201 | #define __cold __attribute__((cold)) | ||
202 | #define __section(S) __attribute__((__section__(#S))) | ||
203 | |||
204 | |||
205 | #ifdef CONFIG_ENABLE_MUST_CHECK | ||
206 | #define __must_check __attribute__((warn_unused_result)) | ||
207 | #else | ||
208 | #define __must_check | ||
209 | #endif | ||
210 | |||
211 | #if defined(CC_USING_HOTPATCH) && !defined(__CHECKER__) | ||
212 | #define notrace __attribute__((hotpatch(0, 0))) | ||
213 | #else | ||
214 | #define notrace __attribute__((no_instrument_function)) | ||
215 | #endif | ||
216 | |||
217 | #define __compiler_offsetof(a, b) __builtin_offsetof(a, b) | ||
218 | |||
219 | /* | ||
220 | * Feature detection for gnu_inline (gnu89 extern inline semantics). Either | ||
221 | * __GNUC_STDC_INLINE__ is defined (not using gnu89 extern inline semantics, | ||
222 | * and we opt in to the gnu89 semantics), or __GNUC_STDC_INLINE__ is not | ||
223 | * defined so the gnu89 semantics are the default. | ||
224 | */ | ||
225 | #ifdef __GNUC_STDC_INLINE__ | ||
226 | # define __gnu_inline __attribute__((gnu_inline)) | ||
227 | #else | ||
228 | # define __gnu_inline | ||
229 | #endif | ||
230 | |||
231 | /* | ||
232 | * Force always-inline if the user requests it so via the .config. | ||
233 | * GCC does not warn about unused static inline functions for | ||
234 | * -Wunused-function. This turns out to avoid the need for complex #ifdef | ||
235 | * directives. Suppress the warning in clang as well by using "unused" | ||
236 | * function attribute, which is redundant but not harmful for gcc. | ||
237 | * Prefer gnu_inline, so that extern inline functions do not emit an | ||
238 | * externally visible function. This makes extern inline behave as per gnu89 | ||
239 | * semantics rather than c99. This prevents multiple symbol definition errors | ||
240 | * of extern inline functions at link time. | ||
241 | * A lot of inline functions can cause havoc with function tracing. | ||
242 | */ | ||
243 | #if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ | ||
244 | !defined(CONFIG_OPTIMIZE_INLINING) | ||
245 | #define inline \ | ||
246 | inline __attribute__((always_inline, unused)) notrace __gnu_inline | ||
247 | #else | ||
248 | #define inline inline __attribute__((unused)) notrace __gnu_inline | ||
249 | #endif | ||
250 | |||
251 | #define __inline__ inline | ||
252 | #define __inline inline | ||
253 | #define noinline __attribute__((noinline)) | ||
254 | |||
255 | #ifndef __always_inline | ||
256 | #define __always_inline inline __attribute__((always_inline)) | ||
257 | #endif | ||
258 | |||
259 | /* | ||
260 | * Rather then using noinline to prevent stack consumption, use | ||
261 | * noinline_for_stack instead. For documentation reasons. | ||
262 | */ | ||
263 | #define noinline_for_stack noinline | ||
264 | |||
275 | #endif /* __LINUX_COMPILER_TYPES_H */ | 265 | #endif /* __LINUX_COMPILER_TYPES_H */ |
@@ -652,9 +652,9 @@ static void remove_node_from_stable_tree(struct stable_node *stable_node) | |||
652 | * list_head to stay clear from the rb_parent_color union | 652 | * list_head to stay clear from the rb_parent_color union |
653 | * (aligned and different than any node) and also different | 653 | * (aligned and different than any node) and also different |
654 | * from &migrate_nodes. This will verify that future list.h changes | 654 | * from &migrate_nodes. This will verify that future list.h changes |
655 | * don't break STABLE_NODE_DUP_HEAD. | 655 | * don't break STABLE_NODE_DUP_HEAD. Only recent gcc can handle it. |
656 | */ | 656 | */ |
657 | #if GCC_VERSION >= 40903 /* only recent gcc can handle it */ | 657 | #if defined(GCC_VERSION) && GCC_VERSION >= 40903 |
658 | BUILD_BUG_ON(STABLE_NODE_DUP_HEAD <= &migrate_nodes); | 658 | BUILD_BUG_ON(STABLE_NODE_DUP_HEAD <= &migrate_nodes); |
659 | BUILD_BUG_ON(STABLE_NODE_DUP_HEAD >= &migrate_nodes + 1); | 659 | BUILD_BUG_ON(STABLE_NODE_DUP_HEAD >= &migrate_nodes + 1); |
660 | #endif | 660 | #endif |
diff --git a/mm/migrate.c b/mm/migrate.c index 4a83268e23c2..c27e97b5b69d 100644 --- a/mm/migrate.c +++ b/mm/migrate.c | |||
@@ -1131,7 +1131,8 @@ out: | |||
1131 | * gcc 4.7 and 4.8 on arm get an ICEs when inlining unmap_and_move(). Work | 1131 | * gcc 4.7 and 4.8 on arm get an ICEs when inlining unmap_and_move(). Work |
1132 | * around it. | 1132 | * around it. |
1133 | */ | 1133 | */ |
1134 | #if (GCC_VERSION >= 40700 && GCC_VERSION < 40900) && defined(CONFIG_ARM) | 1134 | #if defined(CONFIG_ARM) && \ |
1135 | defined(GCC_VERSION) && GCC_VERSION < 40900 && GCC_VERSION >= 40700 | ||
1135 | #define ICE_noinline noinline | 1136 | #define ICE_noinline noinline |
1136 | #else | 1137 | #else |
1137 | #define ICE_noinline | 1138 | #define ICE_noinline |